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UNIV.  OF 

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llBRARY 


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The  Mining  Magazine 

Edited  l)y  T.  A.  RIC.KARD. 
^^  PUBLISHED     AT     SALISBUFO'     HOUSF..     LONDON. 


H 


INDEX  TO  VOLUME  V. 

FROM    JULY    TO    DECEMBER,     1911 


TVT  ^^      T+<ar,,o  in  ifilip«  flip  names  of  books  reviewed  ;  illustrated  articles  are  denoted  liv  a-itn-Kc  y  ■ 
XtoTo°t^^eL7articLTuafthe^^^^^^^^ 


ity-' 


Abercorn  Tin  District,  Rhodesia (;).f.) 230 

idams;  H:::::::::::"::.----Continuou^  Pachuca  Vats  icX) 235 

Africa,  German  Southwest,  Tin  in ^. fr'P-*-^ Jii 

tfrica!  Resources  of  Central Owen  Letcher *213 

Agitator  Vats A.  Grothe  (c.l.).^.^.  ^^73 

tSSuon::::::::::::::::::::::::::::::::::j.  w- «waren  ,cxv.:.:  ^392 

Alaska,  Conditions  m .,„, 

Alaska,  Present  Conditions  in pennV; *315 

llt^'^/w'"'^" :::::;::;:::PineG^^C:g::::::  i 

iK  a:  w::::::::::::::::::::::::::pebbies  for  Tube-Mimng 220 

Alumina  in  Slags,  Determination  of 4C.(.) '^ 

Aluminium  Industry >P-y^ '„ 

Aluminium  Works  in  Norway :^--^-^;^y{::::To{\ 73 

Amalgamation  on  Rand W   R.  Dowhng  (p.  .  ^^ 

Amaliamation  on  the  Rand J.  K.  Thoma^(pX  232 

Amalgamated  Zinc  (De  Bavay's).. Repoit 394 

Anaconda,  Hoisting  by  Compressed  Air  at (p-t.) ^^1 

Anaconda  Smelter  Smoke  Litigation Keport 316 

Anchor  Tin v';;' ■J"- Ror,r,rt ♦471 

Ancobra  Exploration  and  Dredging Renort 158 

Antelope '^      jgg 

Antimony  Ring o'ct'ti"  RiiVipr 36 

Appointments  Vacant ^'V-^-  ^^     „" *Qfii 

A?|all,  Philip Milling  at  Stratton's  Independence *361 

Arizona  Copper Report; :.;■.:     159 

Arizona  Copper f 

Ashio  Copper  Mine,  Japan MT'b'urant 434 

Assays,  Standardization  in ...    ...... .H.  T.  Ouiant m* 

Associated  Gold  Mines  of  West  Australia Report 15b 

Australian  Iron  Resources 

179 

Balcobo  Mine  Assays ;-^'V:  •MniVrKT'lnVi  ""       ,388 

Ball,  H.  S Economics  of  Tube-MiUing  ^.«.  3»« 

BalUMiU  Practice....,,., ,, --■■^J-I^., >?o^ 


.m!  W.  von  Bernewitz *189 

Barrami'a'Mining  and  Exploration ^*^°'!* :;:.;;    413 


Basic  Lining  for  Converters :■  •^-u'lijin  ■o^^i\  2-'3 

Bell,  J.  W..f; Moisture  in  Tube-Mill  Feed ^-» 


Bendigo. 


360 


Bibiani •. ■■ ,„  .  > 

Bisulphite  Process,  Zinc  Extraction  by -•■■;••, "J;'-' 

Blackwater  Mine RlEort 

Blackwater  Mine...., -•;;;  M^uiewson  (r.M 


390 
448 
157 
73 
153 
♦231 
B12 


..(p.<-> 

.^  „^.„.^ (;).M 

:....GoUlCon*t  Paliiver 154 

♦376 


Broken  Hill  Block  10 Report 

Broken  Hill  Block  14 I.-port 

Broken  Hill,  Discovery  at  British  Mine. 

Broken  Hill,  Output  at 

Broken  Hill  South  Silver 

Brown  and  McMiken  Agitator 

Buckinghamshire,  Coal  in 

Buffalo 

Bullcroft  Colliery,  Shaft-Sinking  at _ 

Burma  Mines •. 

Burma  Ruby  Mine . .w'  ii.Vs 

Bunihain,  M.  H... .Finance  of  a  Mine  ..'38,  M25 
Butler,  R.  H.  B Appoinlnieuts  \  a 

California,  Oil  Industry  of  W.  For<trer 

Cam  and  Motor ,, ■'''.,-: 

Camborne  Letter ' j;  •  -■; 

Camp  Bird ^'"P"' 

Camp  Bird,  Early  History  ...  

Camp  Bird— Santa  Gertrudis  ^ 

Cape  Copper 

Cam  Brea  and  Tincrofi 

Cam  Brea  and  Tincroft •■•••-  •--_' 

Peru  iJ- 


Blast-Enrnace  Developments E.  P  ^„.,.„„ 

Bleloch,  \V.  E The  Witirolerfroml  .S;/W<>m. 

Blende  Ore,  Concentrating A "  .;  ' 

Blum's  Method  of  Producing  Zinc  Oxide. 

Bowler,  L.  P 

Braden  Copper  Co p'rVniiirford 

Braden,  Mining  Method  at ^-  ^'"^iS^ti       .      78 

Brakpan '^      '  345 

Brakpan  Mine ie  l)  313 

Brakpan,  New  Plant  at *  •  •'■■         uhj 

Brakpan,  Production  at V;^i"K;."oU.qPhmnix  •51 

Brett,  H.  T Metallurgy  at  Globe  and  Phcenix  ..        ^^ 

Briseis  Tin Report   .  ..    469 

British  Broken  Hill .'   ,  >  4C,i 

British  (Joliiml.ia,  Diamonds  in p ■wiiiinins ♦449 

British  Columbia  Mining ^ :'-"""i„  'n,„  Morth  32'J 

Brock,  R.W Prospecting  In  the  Noitn 


PAUB 

1!« 


Casapalca  Smelter, 

Caucasus  Copper 

Central  Chili  Copper 

Chalcociteas  a  Primary  Mineral.. 

Charcoal  in  Cyanide  Tailing 

Chilean  Mills  v.  Rolls 

Chilean  Mill.  The  .\kron 

Chillagoe ■  •.  ■• 

Chillngoe  and  Einaslcign.. 
China  Clay  Corporation.^.  ._ 
Chinese  Engineering  and  MiniuK. 

Cbino  Copper  Mine 

Chlorinatioii  in  Colorado 
Clancy  Process 


W.  Str.i 

1 

1. 


;.  r 

f  '■ 


1:.  1 . 


.\.  \V.  \V, 
Ureal 


*^'cnn'el  1!  .1 .  iV  .Electrolytic Cyanido  RtKBnen»Holi  ,«■.<.•. 


W.U.  Mill. 

I'vrilo  l">opo»il»  of  I 
Wood  •] 


Club,  Mining  and  MctnlliirgicnI. 
Coal  in  BuckinghainshiK' 
Coaldust  in  Mines 

Coast  Erosion 

Cobalt,  Coiiceiitrating  in 
Cobalt,  Cvauidingat... 
Cobalt,  Geology  of 

Collins,  M.  F 

Collins,  .1.  M ■ 

Colorado,  Cyanidatlon  in.. 
Colorado  11  nib-slake  Fund 
Coinprcssed  Air,  llnistiiig  bv 
Concent nilor,  .lames'. 

Consolidated  Gold  Fields.....^ V—i.rij 

Consoli.latcd  (iold  l^»\'-««  »/««'>;'  Z«*>»n^ 
Consolidated  G.<ld  Fields  of  S<«Uh  Africa. 

ConsoUdaicd  Main  Keel ._ 

Convention  F.ictoi->.  for  Cost  of  Power. 

Coiivertei>.,  Basic  Lining  (or 

Cojijii-r  llii»(ll>i»<k  .  

Cii;i;i#riii  .l(';i(il<ichirt»  Slittf 
Copi'i-r  in  I'yriti 


i(..J.i 


II   ; 
\V.  M 


IVtcnntimtion  o(. 


Copi'cr  in  I  yrne.  i.,..  ......."■ 

Copper  ill  Sandstone  and  sliale w 

Copper  Lead  Matte,  Tnatini: 


ii  VI  n- 

\VtH-«l 


LindKt' 


Copi"'"'-  Marketing. 
Copper  yneen 


V 


b 


•»1 

; -I 


•2x1 

TO 


4M> 

4C7 

78 

8 

•3S5 


isn 


:Rt7 
314 
41S 

»u 

4C4 
416 


V 


THE    MINING    MAGAZINE 


!../:...7............ G.  A.  Denny. 


Cordova,  Alaska 

Cost,  Statements  of. 

Coste,  Eugene,  on  Origin  of  Petroleum. 

Cottvell's  Fume  Settler (p-t.) 

(Jouttet,  J.  F Estimates  of  Extraction 

Crane,  W.  R Mining  Method  at  Smlbury  (e.l.) 

Crane's  Ore  Washer (c.l.) 

Crosley,  W ^...., Mexican  Unrest 

Crosse's  Fine  Grinder .v. (cJ.) 

Cryxtallofirnphji A.  E.  H.  Tutton 

Cuniinings,  \V.  N Buying  Prospects 

Cunnnings,  W.  N Mine  Salting 

Cyanidation  at  Cobalt 

Cyanidation  at  Liherty  Bell \c.l.) 

Cyanidation  at  Treadwell (p-t-) 

Cyanidation.  Beginnings  of J.  S.  MacArthur 

Cyanidation,  Continuous J.  E.  Rothwell  (p.t.)  152, 

Cyanidation  in  Colorado 

Cyanidation,  Losses  in H.  P.  Julian 

Cyanidation  v.  Conjentration G.  .\.  Denny 

Cyanide  Bullion  at  Chatters  Mine,  Refining (c.l.) 

Cyanide  Regeneration J.  E.  Clennell  (c.l.) 

Cyanide  Tailing,  Charcoal  in (p.t.) 

Cyaniding  Concentrate R.  Lindsay  (e.l.) 


*183 
384 
343 

*308 
43f) 
15-2 
234 
41 
73 
154 
383 
224 

*20(i 
152 

■4(54 
40 

*3r2 
337 

■284 
433 
392 
73 
232 
313 


De  Kalb.C Slime  Settlement 305 

Denny,  G.  A Statements  of  Costs 384 

Denny,  G.  A Ciyanidation  v.  Concentration 433 

Denver  Letter 22 

Diamonil,  The W.  R.  Cattelle 314 

Diamonds  in  British  Columbia (p  (.) 461 

Dictionary,  Terhnical,  Vol.  XI.  Metallurgy 236 

Dolcoath Report 237 

Dome  Mine,  Treatment  Plant  at (p.t.) *7f 

Douglas,  James,  on  Copper  Queen 415 

Dowgas  Mine 424 

Dowling,  W.  R Amalgamation  on  Rand  (c.l.) 73 

Draper,  T Mining  in  Madagascar *439 

Dredging  in  New  South  Wales (c.l.) 73 

Drill,  Tippett's  Stope (c.l.) 73 

Drills  at  Robinson  Deep 112 

Duralnniin (p.t.) 70 

Durant,  H.  T Standardization  in  Assays 434 

Durban  Roodepoort  Deep Report 78 

Dust,  Laying W.  M.  Thornton  (c.l.) 234 

Dust-Collector  for  Mines (c.l.) 73 

Dutch  East  Indies,  Gold  in [  290 


East  Rand  Episode 170,  172.  257,  340 

Eastern  Smel t ing  Co 

Eclipse  Filter  for  Slime (p.t.)...... 

Eileen  Alannah ' 

Einasleigh  (Copper 

Einasleigh  Copper , ..Report.!!!" 

El  Oro  Mining  and  Railway Report 

Eldorado Report. 

Electrolytic  Assay  of  Gold  Solution (p.t.).. 

Emmons  Memorial 

Engineers  as  Financiers 

English  Crown  Spelter Report 

Erosion,  Coast . 

Estimates,  Meticulous 

Etheridge  Mining  Distri.t ..'. 

Evans-Stansfield  Electric  Steel (c.l.) 

Extraction,  Estimates  of .j.  P.  Couttet!!!!!! 

Famatina   Report 

Ferreira,  Open-cut  at 

Pilling  Stopes E   Pam 

Filter  for  Slime,  Ellipse ip  t  ) 

Finance  of  a  Mine 

Finan.-e  of  a  Mine ivi.  H.  Buniha'm,  '*38!  M25!  209  *280 

Pmches  and  Finance  . 

Fine  (Grinding ii^iiiiiiiiiiiiiiA.' wlAilen:;:::: 

biniay,  .1.  R        Valuation  of  Michigan  Mines    197 

Fin  ayson,  A.  M Pyrite  Deposits  of  Hiielva 

Flotation  Processes D.  P.  Mitchell  (c.l.) 

Pomes'  Slime  Thickener ,„  ,  (■ 

Porstner  W Oillndustry  in  California  !. 

Poster,  D.  F Ball-Mill  Practice... 

Frontena  •,  Concentration  at..  .  i„  t  \ 

Fronteiiac  Consolidated 

Fundamental  Factor 


<^ahl,  R Chilean  Mills 


V.  Kolls  (p.t.).. 


,412 

95 

308 

410 

404 

320 

*317 

158 

465 

410 

17 

79 

102 

341 

33 

314 

436 

474 

*111 

*295 

.309 

417 

*444 

96 

35 

,277 

383 

467 

386 

291 

304 

228 

414 

420 

70 


Gascovne  V n  -^^^-^  Settlement  (p  t.) n49 

6eEhf.is'\)eep::.::.:: ""'''  "'^'^"^^  °"  '\^,zi *'^^ 

Generosity  of  Science.....'.;; "^"^ ol^ 

Giant  Mines RBn'^vV wSi 

Giesecke  Mill ?4   pq' Qi  o?o 

Giese^ke  Mill  ;^^;  f '  9*'  2.j9 

GirouxMine,  Fireat..;!!; ^^    ' 2^^ 


Globe  &  Phoenix Report 316 

Globe  &  Phoenix,  Metallurgy  at H.  T.  Brett..  :..  *51 

Globe  &  Phoenix,  Metallurgy  at [p.t.) 386 

(ilycerine,  Price  of (v.t  ) 67 

Gold  Const  Palaver L.  P.  Bowler 154 

Gold,  Distribution  of P.  C.  Lincoln  (p.t.) 71 

Gold  Mine,  Most  Proiiuctive L.  O.  H 304 

Goldfleld  Consolidated  Mill ....(p.t.) 68 

Goldschmidt's  Refractory  Alloys (p.t.) 227 

Gonzalez,  Grothe  &  Salazar,  Mining  Industry  of  Mexico 154 

Goss  Moor  Alluvial 424 

Granville  Mining  Co If55 

Graphite,  Origin  of A.  N.  Winchell  (c.J.) 75 

Great  Cobar Report 474 

Great  Cobar,  Mining  and  Metallurgy  at...D.  Clark  (c.l.) 467 

Great  Boulder  Proprietary Report 76 

Great  Pingall Report 75 

Great  Pingall,  Geology  of 12 

Great  Fitzroy Report 469 

(irenville  United Report 238 

Grinding  Machines .' 259 

Grothe,  A Agitator  Vats  (c.l.) 73 

Gwalia  Consolidated Report  469 

Hackney,  N.  G Malaria 384 

Hainauit Report 394 

Hampden  Cloncurry Rejiort 157 

Harbord,  P.  W.,  on  Metallurgy  of  Zinc 252,  '►310 

Harz,  Metallurgy  in  the O.  H.  Hahn  (jr./.) 73 

Hatch,  P.  H Rand  Gold  Indu.stry  (p.t.) +150 

Hellmann,  P.,  on  East  Rand  Deiwsits 340 

Henry,  J.  D Oilfields  of  Sew  Zealand *393 

Hoisting  by  Compressed  Air (p.t.) 231 

Hooper,  Edward,  elected  President  of  I. M.M 328 

Hoover,  H.  C Speculation  in  Mining 301 

Hoover,  T.  J Percentages  of  Recovery 219 

Hoover,  T.  J Recent  Progress  at  Maikop *45 

Hudson  Bay  Concentrator (p  t.) *466 

Huelva  Pyrite  Deposits H.  P.  Collins *]21 

A.  M.  Finlayson aSS 

Huelva,  Specular  Iron-Ore  in (pt.) 149 

HuS  Electrostatic  Separator (c.l.) 73 

Huff  Electrostatic  Separator (pt.) 308 

Huntoon,  L.  D Errors  in  Sampling  [c.l.) 1^ 

Ida  H Report 320 

Imbert  Fitzgerald  Zinc  Process [p.t.) *389 

Imperial  College  Union *333 

Impoverishment  in  Depth 98,  340 

Indexes  of  Technology 180 

Ireland.  Coal  in 218 

Iron  Ore  in  Huelva.  Specular (p.t.) 149 

Iron  Ore,  Sea-Transport  of (c.l.) 152 

Iron  Ores  of  Lapland (p.t.) 388 

Iron  Ores  of  Lorraine (c.l.) 392 

Iwanow,  W.  N Determining  Copper  in  Pyi'ite  [p.t.) 148 

•James'  Concentrator (c.l.) 152 

•libutil  Gold  .Mines  of  Anantapui- 5,  9 

.Johannesburg  Letter 25,  110,  M89,  '267,  *.345,  421 

Johnson.  H.  H Progress  at  Porcupine ■!71* 

Johnson's  Electric  Zinc  Furnace [p.t.) *310 

Jumbo Report 396 

Jumpers Report 474 

Julian,  H.  P Losses  In  Cyanidation 284 

Juneau  Letter 105 

Kafue  Copper  Co 244 

Kalgoorlie,  Ball-Mill  Practice  at... .M.  W.  von  Bernewitz...  '139 

Kern  River  Oilfields 8 

Kerr  Lake Report 395 

Keyes,  C.  R Ore  in  Clay  Selvages  (p.t.) 229 

Kildonan  Goldfleld 131 

Kinta  Tin Report 317 

Kleinfonteiu,  Electrolytic  Assay  of  Gold  Solutions  at 

(pt.) 465 

Klondyke,  Recent  Progress  at P.  L.  Morris *374 

Komata  Reefs,  Metallurgy  at (c  I.) 152 

Krupp  Ball  Mill  Practice M.  W.  von  Bernewitz *139 

Kyshtim  Corporation Report 155 


Langford.  P Mining  Method  at  Braden. 

Lapland  Iron  Ores (pt.). 

Lass,  W.  P Cyaniding  at  Treadwell  (p  t.). 

Law.  Mininq H.  W.  MacParren. 

Lead  \ssay R.  T.  Wilder  (c  /.).. 

Lead  Smelting  in  Missouri [c  I.). 

Leatherbee,  H Vanadium  in  New  Mexico.. 

LenaGoldtields Report . 


*376 
388 
*464 
2.36 
314 
152 
282 
470 

Letcher,  Owen Resources  of  Central  Africa '213 

Lett,  S.  J Malaria 306 

Liberty  Hell,  Metallurgy  at (c.) 152 

Lime,  Determining  the  Quality  of (p.t) 466 


THE    MINING    MAGAZINE 


Lincoln,  F.  C Distribution  of  Gold  i;).f.i 71 

Lindgren,  W 407 

Lindgren,  W Copper  in  Sandstone  and  Shale  (/i.M 4(51 

Live  Oak,  Purchase  by  J.  D.  Ryan 431 

Lecher's  Drill  for  Deep  Holes {/■.I.) -234 

Loetschberg  Tunnel W.  L.  Saunders  (c./.) 152 

Lorraine  Iron  Ores (<■'.) 392 

Louis,  H Metallurgy  of  Tin 236 

Louvrier-Louis  Zinc  Furnace (r.(.) 235 

Lowe,  H.  P Report  on  Frontenac 414 

I.iiell,  The  Students' J.  W.  Judd 74 


Mabson,  R.  R Miiic^  of  Africa 

MacArthur,  J.  S Beginnings  of  Cyaiiidatioii     .  . 

MacFarren,  H.  W ...Mining  Laic 

Mackay,  A.  N Tube-Mill  Lining 

McKiniey  Darragh-Savage P.eport 

McKesson  Sizer (<•.?.) 

Maclaren,  J.  Malcolm Report  on  Great  Fingall 

McLeod's  Concentrator (c  '•) 

Madagascar,  Mining  in T.  Draper 

Maikop,  Recent  Progress  at T.  J.  Hoover 

Main  Reef  West Report.    ... 

Malaria,  Palliative  for S.  .T.  Lett 

N.  G.  Hackney 

Mathewson,  E.  P Blast-Purnace  Developments  (c./.) 

Mawchi  Tin  and  Wolfram  Mines 

Mayer,  Ralph  A Porcupine 

Melbourne  Letter 32,  114,  I'Ji),  274,  352, 

Melting  Metals  at  the  Mint 

Melones,  Mining  at ic.l.) 

Mennell,  F.  P Mining  in  Rhodesia '■ 

Mercury  tires,  Low-6rade ip.t.) 

Merrillj  C.  W Zinc-Dust  Precipitation  ip.t.) 

Messina Report ' 

Metal  Markets 34,  120,  201,  204,  359, 

Mexican  Affairs,.... L.  Salazar 

Mexican  Unrest W.  Crosley 

Mexico  Letter 30,  112,  n93,  272, 

Mexico  Mines  of  El  Oro Report 

Mexico,  Mining  Indvutry  of. 

Gonzalez,  Grothe,  and  Salazar 

Miller,  W.  G Discovery  of  Nipissing 

Miller,  W.  G Geology  of  Cobalt  (p.t.) 

Mines  of  Africa R.  R.  Mabson 

Mine  Accounts K.  C.  Parrish  (c./.i 

Mine  Roofs,  Supporting ('■•'•) 

Mineral,  A  Strange (V-t-) 

Mii.crol  Iniliixln/,  Vol.  XIX 

Minerals,  The  IVorld's L.  J.  Spencer 

Miner's  Protest,  A Reef  Miner 

Ralph  Stokes 

Mining  Method  at  Braden F.  Langford 

Mining  Method  at  SudViury W.  R.  Crane  (c.l.) 

Mitchell,  D.  P Flotation  Processes  ic./.) 

Modderfontein  B  Equipment.. {c.l.) 

Modderfontein,  New 

Modderfontein,  New Report 

Mond  Nickel Report 

Morris.  P.  L  Recent  Progress  at  Klondyke 

Mount  Bischoff Report 

Mount  Elliott  Mine 

Mount  Lyell Report 

Mount  Lyell  stx'ike 

Mount  Morgan Report 

Mountain  Copper Report 

Mungana  Chillagoe '. Report 

Naraguta  Tin Report 

Natoma  Dredge,  Large ('■•'•> 

Natomas  Consolidated Report 

New  York  Letter 29,  117,  196,  277,  3.5.=i, 

New  Zealand,  Iron  Ore  in (c.l.) 

New  Zealand,  OilfiehUof J.  D.  Henry 

Nickel-Copper  Matte,  Roasting ('■■'  ) 

Nickel  Ore  Electric  Smelting  of  "'•'•) 

Nigerian  Tin  Corporation Report 

Nipissing Report.. 

Nipissing  and  Camp  Bird,  Early  History 

Nipissing,  Discovery  of .- 

Nipissing,  Discovery  of ...'.     ...W.  G.  Miller 

Nissen  Stamp (P  <•) 

North  Anantapur Report 

North  Broken  Hill Report 

North,  Prospecting  in  the R.  W.  Brock 

Northern  Territory  Explorers 

Northern  Terrors 

Norway.  Water  Power  in {c.l.) 

Nourse  Mines Report 

Official  Opinions '^^'\ 

Ohinenmri  River  Sand,  Cyaniding (?•'•) '^~\ 

Oil  Deposits  Geology  of ('"•'•) '^'^^ 


4GS 

4(1 

230 

35 

79 

313 

12 

73 

439 

45 

397 

307 

384 

73 

9 

42 

428 

452 

313 

132 

148 

307 

473 

432 

37 

41 

426 

395 

154 
301 

'38S 
468 
73 
152 
464 
314 
468 
381 
435 

^376 
152 
407 
234 
346 
398 
180 

►374 
310 
115 
409 
428 
240 
*79 

*319 

159 
391 
390 
4;iO 
314 
393 
235 
392 
317 

80 
202 

94 
301 
*402 
318 
319 
222 
252 
429 

74 
172 


Oil  from  Feed-Water,  Removing (;).'.! 312 

Oil  Industry  of  California W   Forstner '291 

Oil  Industry  of  Roumania R.  C.  N.  Twite '453 

Oilfields  of  New  Zealand J.  D.  Henry 393 

Oriental  Consolidated Report 470 

Oro  Banda,  West  Australia.  246 

Oroya  Leonesa Reiwrt 289 

Orsk  Goldfields Heport 155 

Otavi  Mines Report 160 

Ouro  Preto Report 470 

Overwinding,  Dalglish's  Apparatus  to  Prevent (c.l.) 234 

Overwindine.  Landales'  Apparatus  for  Prevention  of 

(c./.l 391 

I'achuca,  Ore-Shoots  at {p.t.t  311 

Pachuea  Vats H.  Adams  (<■./.) 235 

I'am,  E Stope-Filling 295 

Paragon  Electric  Furnace ic.l.) 392 

Park,  J Tliecdolite  Snri-cyinfl  and  Levelling 468 

Parmelee,  H.  C Percentage  of  Recoven 382 

Paul,  F.  W Report  on  Australian  Iron  Resources 443 

Pena  Copper Report  315 

Pena  Copper  Mines 406 

Personal 44,  138,  208,  279,  3ti0,  438 

Petroleum,  Origin  of 343 

Pinch-Effect  Electric  P'urnace {c.l.) 392 

Placers   Recovering  Fine  Gold  from id.) 314 

Platinum  A  Gold  Concessions 18 

Plymouth  Consolidated,  California 425 

Poderosa  Report '76 

Pope,  F.  .J. Ore-Shoots  at  Pachiicu  ip./.l 311 

Porcupine. Ralph  A.  Meyer 42 

Porcupine  Fire _• 101 

Porcupine,  Progress  at 265,349,  429 

Porcupine,  Progress  at H.  H.  Johnson '371 

Porcupine,  Recovery  of 186 

Frestea  Block   \ Report 75 

Prestea  Episode 171.  256 

Presten,  Progress  at 16,  19 

Progress  Mines Report 157 

Prospecting  for  Iron  Deposits (c-'-) 73 

Prospects,  Buying 182 

Prospects,  Buying W.  N.  Cummings 383 

Pulitzer,  .Joseph 328 

Pumps,  Efficiency  of  Suction {p.t.) 70 

Pvrite  Deposits  of  Huelva H.  F.  Collins *121 

A.  M.  Finlayson 383 

Quartano,  A Moisture  in  Tube-Mill.Peed 223 

Queensland  Miners'  Health  Commission (p.^) 227 

174 

*202 

379 

10 

"150 

100 

28 

66 

73 

38 

219 

:i82 

154 
305 

390 
'47 
235 
414 
401 
77 
■132 
332 
402 

,  309 
427 
239 
112 
394 
385 
78 
152 
.312 
453 
219 


Ramsay,  Sir  AV.,  and  the  Coal  Supplies 171 

Rand,  beep  Mining  on  the R.  Gascoyne 

Hand,  l<;arly  Days  on  the D.  B.  Schuitema 

Hand  Ji^cononiies 

liand  Gold  Industry F.  H.  Hatch  ip.t.) 

Hand.  Results  on  the 

Handfontein  Electric  Plant 

Rankin's  Process 

Rankin's  Process (<■•'•) 

Recovery,  Percentage  of C.  W.  Wright 

T.  .J.  Hoover 

H.  C.  Parmelee 

Hedmavne.  R.  A.  S Ventilation  of  .Mines 

Reed,  Frank Ventilation  in  Mines  .  .. 

Refining  Gold  and  Silver  Bullion  at  San  Francisco  Mint 

{l>t.) 

liefoniia  Mine C.  S.  Thomas 

Heid's  Electric  Smelting  Process {r.l-) 

Reporting,  Loose 

Review  of  Mining 2.  84.  162,  242,  .3'22 

He/.ende Report 

Rhodesia,  Mining  in P.  P.  Mennoll 

Ithodesia;  Prospects  in 

Hliodcsian  l-^xploration  and  Development 

Hliodesian  Tin i/i./ 1 

67,  2;io 

Hio  Tinto   Chihuahua 

Robinson  Dec)) Report 

Hohinson  Deep.  Machine  Drills  at 

Hooibcrg  Minerals Report 

Hoies.  Wire,  for  Mining  Purposes 

Rose  Deep Report 

Rothwell's  Continuous  Cyanidation {r.l.) 

Rothwell.  -LM Continuous  Cyanidation  (7)./.) 

Roumanian  Oil  Industry R-  I'-  N    Twite 

Rumbold,  W.  R Values 

St.  Ives  Consolidated  New  Capital ^'^\ 

St   Ives  Consolidated Report 2!18 

St.  John  del  Rey Report 76 

St.  .lohn  del  Rey,  Temperatures  at (pt-) W* 

Salazar,  L Mexican  Affairs 37 


THE    MINING    MAGAZINE 


Salisbury  Gold Report 

Salt  from  Salt  Lake (p-t.) 

Salt  Lake  City  Letter 198 

Salting,  Mine W.  N.  Cmnmings 

Sampling,  Errors  in L.  D.  Huntoon  (c.i.) 

Sampling  in  Chile L.  W.  Strauss 

Sampling,  Mine S.  F.  Shaw 

San  Francisco  del  Ore 

San  Francisco  Letter 109,  191,  348 

San  Miguel  Copper Report 

Santa  Gertrudis 

Santa  Gertrudis Report 

Sauer,  Dr.  H.,  Resignation 

Saunders,  W.  L Tunnel  Driving  in  the  Alps  (c./.) 

Schmitt,  C.  O.,  on  Rand  Practice 

Sehuitema,  D.  B Early  Days  on  the  Rand 

Scotland,  Gold  Placers  in 

Scranton,  Caving  at (c.Z.) 

Scranton,  Supporting  Mine  Roofs  at (c./.) 

Sea  Transport  of  Iron  Ore ...(c.l.) 

Seasonal  V'ariations 

Secretaries 

Shaft,  Circular,  on  Rand 

Shaft  sinking  at  Rand  Klip 

Shaft  sinking  in  Silesia {c.l.) 

Shaft-sinking  in  Wet  Ground ip-t.) 

Shafts,  Concrete (p-t.) 

Shari)ley,  H Blackwater  Mine 

Shaw,  S.  F ..Mine  Sampling 

Sheba  Gold Report 

Silver  Minerals  in  Clay  Selvages C.  R.  Keyes  (p.t.) 

Simmer  &  .Jack Report 

Sintering  at  Refonna (c.l.) 

Sintering  Iron  Ores J.  Gayley  (p.t.) 

Sizing  for  Amalgamation (c.l.) 

Slime  Settlement B.  L.  Gardner  (p.t.) 

Slime  Settlement C.  de  Kalb 

Slime,  Treating  Accumulated. ..J.  E.  R.  Adendorf  {c.l.) 

Slime  Treatment  at  Kalgoorlie {c.l.) 

Smelter  Gases.  Neutralizing (p.t.) 

Smelter  Smoke  Litigation 

Specific  Gravity  of  Pulp (c.l.) 

Speculation  in  Mining H.  C.  Hoover 

Spencer,  L  J The  World's  Minerals 

Square-Set,  Modified (p.t.) 

Standardization  in  Assays H.  T.  Durant 

Statistics  of  Production 7,  92,  169,  249,  358, 

Steel  Corporation  Prosecution 

Steel  Production  of  the  World (pt.) 

Stokes,  Ralph ; A  Miner's  Protest 

Stope-Filling Edgar  Pam 

Stratton's  Independence Report 

Stratton's  Independence,  Milling  at Philip  Argall 

Strauss,  L.  W Casapalca  Smelter. 

Strauss,  L.  W Sampling 

Strike,  The  Railway 

Sudan,  Mineral  Depositii  of. S.  C.  Dunn 

Sudbui7,  Mining  Methods  at (c.l) 

Surprise  Mine 

Symons  Crusher  for  .Jig  Middlings......  .......... .......(c!J) 

Talisman Report 75 

Tanami  Goldfield 114 

Tanganyika  Concessions 410 

Tanganyika  Concessions,  Holdiiigs  in 329 

Taquah  lietter ...^^..^.^..  19 

Taquah  Mining  and  Exploration ..Report 75 

Taxco  Mines Report 476 

iechnical  Sensationalism .J.  C.  S.  Whittuck 41 


PACE 

.  318 
.     228 

,269 
224 
1.52 

*433 

*4.57 
326 
425 
316 
330 
396 
402 
152 
41 
379 
131 
313 
152 
152 
418 
419 

*267 
4-22 
391 

*147 
227 
448 

*457 
472 
229 
473 
73 
233 
314 

'■149 
305 
314 
73 
388 
13 
152 
301 
468 

*232 
434 
400 
355 
148 
435 

*295 
475 

*361 

,438 

*433 
175 
468 
152 
402 
152 


59 


Temperatures  at  St.  .John  del  Rey (p  t  ) 

Temperatures,  Mine (p.t.). 

ThewioHte  Surveijliig  and  Levelling .j.  Park 

Thickener,  Forbes (p  f  \ 

Thiogen  Process,  Young's..  ..    . (n't\ 

Thistle  Etna..... :;::;.'::::::::::::zR^ort::::: 

Thomas,  CS Reforma  Mine 

Ihonum  Mmerals,  Occurrence  of.  (c  ;  ) 

Timbering,  Modified  Square-Set..  (nV) 

Timbering  Shafts H.  G.  Elw'es(c;i'  

Tin,  Analyses  of  Standard  Brands  of...  (p  t  ) 

Tin  Assay S.  E.  Linder  (c:/.'):.:.:, 

Tm  Contract,  Standard („  t  ) 

Tin  in  Abercorn  District,  Rhodesia..  (»  t) 

Tm  m  Enterprise  District,  Rhodesia  (pt  ) 

Tm  m  German  South-West  Africa..  .  (»  t) 

Tin  m  Malaya. J.  B.  Scrivenor'(r./.  :'7 

lin  in  Rhodesia („  (  [ 


*68 
148 
468 

*386 
388 
158 
*47 
235 

♦232 
391 
390 
314 
464 
231) 
67 
461 
392 
309 


Tin  in  South  Africa U-.t.) 235 

Tin,  Metnllurgit  of. H.  Louis 236 

Tin,  Sale  of...'. 334 

Tin  Smelting,  Electric (c.l.) 314 

Tin,  Wood J.  H.  Collins  (c.l.) 152 

Tippett's  Stope  Drill (o./.) 73 

Titanium  Ores,  Distribution  of (c.l.) 235 

Tolima Report 470 

Tomboy Report *475 

Toronto  Letter 20,  108,  '186,  265,  *349,  429 

Trade  Notes 82, 160,  240,  320,  398,  476 

Treadwell,  Cyanidingat (p.t.) ■*464 

Treasurv  Gold Report 160 

Troitzk"Goldfields Report 155 

Trollhattan,  Hvdro-Electrio  Plant  at (c.l.) 314 

Trollhattan,  Zinc  Metallurgy  at 252,  *310 

Trollhattan,  Zinc  Metallurgy  at (p.t.) 388 

Truscott,  S.  J Bleloch's  Witwatersrand  System.....      153 

Tube-Mill  Peed,  Moisture  in J.  W.  Bell y23 

A.  Quartano 223 

Tube-Mill  Lining A.  N.  Mackay *35 

Tube-Milling,  Economics  of H.  S.  Ball  (p.t.) 388 

Tube-Milling,  Pebbles  for A.  W.  Allen 226 

Tungsten  Ores,  Concentrating (c./.) 234 

Tungsten  Ores  in  Queensland (c.l.)..         235 

Tunnel  Driving.. (p.t.) *307 

Tunnel  Driving  in  Alps W.  L.  Saunders  (c.l.) 152 

Tutton,  A.  E.  H Crjistallographv 154 

Twite,  R.  C.  N Oil  Industry  of  Roumania ♦453 

Uruguay  Consolidated Keport 476 

Utah  Copper Report 81 

Valuation  of  Shares,  Official 178 

Valuation  of  Shares,  Official Speculator 222 

Values... W.  R.  Rumbold 219 

Valuing  Mines M.  Webber  (c.l  ) 313 

Van  Ryn  Deep,  Reserves  at 190 

Vanadium  in  New  Mexico B.  Leatherbee 282 

Ventilation  in  Mines Frank  Reed 305 

VeiiiiUiliou  of  Mines R.  A,  S.  Redmayne 1,54 

Ventilation,  Reversing (c.l.) .313 

Victoria  District,  Rhodesia,  Tin  in (p.t.) .%9 

Village  Main  Reef Report 79 

Vogelstruis  Estates Report 474 

Waihi,  The  Future  of  the d33 

158 
466 
391 
239 
313 
329 


Wanderer Report. 

Warwick,  A.  W Clancy  Process  (p.t.) 

Water  used  in  Cyanidation (c.l.) 

Weardale  Lead Report 

Weighing  Ore  on  Travelling  Belts (f.?.)  .... 

West  African  Chamber  of  Mines 


West  Kittv,  New  discovery  at 274 

Wheal  Kitty  &  Penhalls +159 

Wheal  Kitty,  Decline  in  Output 274 

Wheal  Vor Report 237 

Whim  Well  Copper Report 395 

Whitehouse  and  Wotherspoon Mine  Temperatures 

ip.t.) 148 

Whittuck,  .J.  C.  S Technical  Sensationalism 41 

Williams,  P British  Columbia  Mining '449 

Willoughby's  Consolidated Report 157 

Winding  Engine  for  Champion  Reef (<■•'•) 391 

Wittich,  L.  L Lead  Smelting  in  Missouri  (c./.) 152 

Witwatersrand  Sygtem W.  E.  Bleloch 153 

Wright,  C.  W Percentage  of  Recovery 38 

Wyoming,  Mineral  Besources  of. 236 

Yukon  Gold  Co ^88 

Zaaiplaats  Tin Report 394 

Zaaiplaats  Tin  Deposit id.) 235 

Zeehan  Montana Report *80 

Zinc  Corporation,  Flotation  at (e.l.) 467 

Zinc  Distilling  at  Trollhattan .'......(p.t.)......  3fc8 

Zinc-Dust  Precipitation (p.t.) 307 

Zinc  Extraction  by  Bisulphite  Process (p.t.) 390 

Zmc  Furnace,  .Johnson's  Electric (p.t.) ♦310 

Zinc  Furnace,  Louvrier-Louis id.) 235 

Zinc-Lead  Ores  at  Trollhattan,  Smelting (p.t.) *310 

Zinc  Metallurgy 2.52 

Zinc  Ore,  Concentrating (p.t.) ^231 

Zinc  Oxide,  Blum's  Process (p  t.) 312 

Zinc  Process,  Imbert-Fitzgerald (p.t.) ^389 

Ziitns  Metallurgie  des H.  Mennicke 2.36 


The  Mining  Magazine 


Vol.  V. 


LONDON.  JULY   1911. 


No.  1 


Scientta   non   habet  inimicum  nisi   ignorantetn. 


T.    A.    RICKARD,    Editor.  EDGAR    RICKARD,    Business  Manager. 

PUBLISHED  BY  THE  MINING  PUBLICATIONS  LTD.,  at  819  SALISBURY  HOUSE.  LONDON.  EC 

Issued    on    the    15th    day   of   each    month. 

Telegraphic  Address  :    OUgoclase.     Codes:  McNeill,  both  editions.     Telephone:    8938   London    Wall. 

Branch  Offices  • 
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CONTENTS. 


Review  of  Mining. 


PAGE 
2 

7 


Statistics  of  Production 

Editorial 

Notes 8 

Rand  Economics 10 

Great  Fingall  12 

Smelter  Smoke  13 

The  Giesecke  Mill 14 

Prestea 16 

Engineers  as  Financiers  17 

Platinum  &  Gold  Concessions 18 

Special  Correspondence 

Taquah  19 

Toronto 20 

Denver 22 

Johannesburg 25 

New  York 29 

Mexico 30 

Melbourne 32 

Metal  Markets 34 

Discussion 

Tube-Mill  Lining A.  N.  Mackay  35 

Fine  Grinding A.  W.Allen  35 

Appointments  Vacant 

R.  H.  B.  Butler  36 

Mexican  Affairs Leopoldo  Salazar  37 

Calculations    of    Percentage    of    Re- 
covery  C.  W.  Wright  3S 

The  Finance  of  a  Mine  

M.  H.  Burnham  38 

Beginnings  of  Cyanidation 

John  S.  MacArthur  40 


PAGE 

Mexican  Unrest William  Crosley  41 

Technical  Sensationalism 

J.C.S.  Whitttick  41 

Personal 44 

Articles 

Porcupine Ralph  A.  Meyer  42 

Recent  Progress  at  Maikop 

Theodore  J .  Hoover  45 

The  Reforma  Mine 

C.  S.  Thomas,  Jr.  47 

Metallurgy  at  the  Globe  &  Phoenix  ... 

H.  T.  Brett  51 

The  Casapalca  Smelter,  Peru  

Lester  W.  Strauss  59 

Precis  of  Technology 

The  Giesecke  Ball-Mill   67 

Tin  in  Rhodesia 67 

Price  of  Glycerine  67 

Temperatures  at  St.  John  del  Rey  ....  68 

Goldfield  Consolidated  Mill   68 

Chilean  Mills  versus  Rolls 70 

Duralumin  70 

Efficiency  of  Suction  Pumps 70 

The  Distribution  of  Gold  71 

Treatment  Plant  at  the  Dome  Mine, 

Porcupine 73 

Current  Literature 73 

Books  Reviewed 74 

Company  Reports 75 

Trade  Notes  82 


REVIEW    OF    MINING 


Introductory. — Since  our  last  issue  ap- 
peared the  course  of  business  has  been  inter- 
rupted by  the  hoHdays  incidental  to  the  Coron- 
ation. During  the  festivities,  and  for  many 
days  preceding,  no  business  was  done.  In- 
terest shifted  from  the  City  to  the  West  End, 
from  the  Stock  Exchange  to  the  Abbey.  An 
afterglow  of  celebration  prolonged  the  period 
of  financial  inactivity,  but  when  the  tumult 
and  the  shouting  died,  when  the  Captains  and 
the  Kings  departed,  the  whirring  wheels  of 
industry  again  made  themselves  heard  and  the 
chink  of  money  on  the  counters  of  speculation 
once  more  attracted  the  man  in  the  street. 
The  low  ebb  of  business  during  the  period  of 
jubilation  is  indicated  by  the  June  '  account ' 
on  the  Stock  Exchange  ;  this  was  insignifi- 
cant in  its  volume.  All  commitments  were 
curtailed.  Even  the  buying  that  usually  pre- 
cedes a  holiday  interruption  was  notably  ab- 
sent. However,  general  conditions  have  con- 
tinued favourable.  Money  is  easy  and  the 
technical  position  on  the  Exchange  is  healthy. 

Transvaal.  —  The  statistics  for  May 
showed  a  record  gold  output  of  685,951  oz., 
worth  ;^2, 91 3,734,  this  being  an  increase  of 
18,237  oz.  or  £11  ,\bl  as  compared  with  April, 
which,  it  must  be  remembered,  is  a  30-day 
month.  In  May  last  year  the  output  was 
worth  ;^2,693,785.  The  chief  decrease  was 
at  the  East  Rand  Proprietary,  owing  to  the 
accident.  Compensating  gains  were  made  by 
the  Crown  Mines,  New  Modderfontein,  Sim- 
mer &  Jack,  and  Rose  Deep.  It  is  appar- 
ent that  the  Transvaal  will  soon  be  yielding 
;^3,000,000  worth  of  gold  per  month,  and  the 
time  is  near  when  the  maximum  production 
will  be  attained.  At  present  the  new  pro- 
ducers are  gaining  on  the  expiring  mines,  but 
this  satisfactory  condition  is  subject  to  known 
limitations.      According    to    the    last    official 


figures  (for  March)  there  were  67  companies 
and  9911  stamps  at  work,  as  against  71  com- 
panies and  9836  stamps  in  May  1910. 

We  note  that  the  President  of  the  Chamber 
of  Mines  recently  made  a  reference  to  the  un- 
expected competition  for  Kaffir  labour  occa- 
sioned by  railway  construction  in  the  Trans- 
kei,  and  he  expressed  the  hope  that  within  a 
year  the  mines  on  the  Witwatersrand  would 
have  "  in  their  employ  over  80%  of  their  de- 
clared requirements."  On  the  same  occasion 
Mr.  George  Albu  said  that  he  "  viewed  with 
the  greatest  alarm  the  constant  rise  in  native 
labour  wages."  He  advocated  co-operative 
action  among  the  groups,  eliminating  contrac- 
tors and  other  middle-men.  Thus  the  unneces- 
sary competition  may  be  avoided.  The  labour 
returns  exhibited  a  decrease  of  3936  nat'ves 
on  gold  mines  as  compared  with  May  last 
year,  when  the  native  labour  supply  showed 
a  gain  of  150  on  the  month  preceding.  Be- 
tween May  and  November  last  year  the  de- 
crease, owing  to  the  seasonal  migration  of 
Kaffirs,  was  5937.  A  corresponding  loss  is 
likely  this  year.  The  decrease  for  June  was 
3447  natives. 

The  starting  of  new  mills  is  indicated  by 
the  enlarged  tonnage  crushed  on  the  Rand. 
In  May  2,002,926  tons  were  treated  at  a  total 
cost  of  17s.  lOd.  per  ton,  so  that  the  average 
yield  of  27s.  6d.  left  a  profit  of  9s.  8d.  per  ton. 
The  cost  was  threepence  more  than  in  April 
and  the  yield  one  penny  less ;  hence  the 
profit  was  4d.  per  ton  less  ;  indeed,  it  was  the 
lowest  recorded  for  12  months.  On  the  other 
hand,  the  total  profit  of  ^956,823  was  the 
highest  since  last  August. 

Fifteen  mines  on  the  Rand  have  individu- 
ally contributed  over  ^5,000,000  to  the  world's 
stock  of  gold.  According  to  the  figures  pub- 
lished by  the  Chamber  of  Mines,  and  quoted 


JULY,    1911 


herewith,  it  appears  that  the  biggest  total  is 
that  of  the  Crown  Mines,  which  includes  the 
yield  of  the  Crown  Reef,  Langlaagte  Deep, 
and  Robinson  Central  Deep,  but  not  that  of 
the  Bonanza.  The  finest  showing,  however, 
is  undoubtedly  that  of  the  Robinson,  which, 
on  a  gross  output  of  ^14,730,170,  has  given  its 
shareholders  the  princely  profit  of  ;^8, 199,688. 
This  mine  has  produced  4,801,075  tons  of  ore 
averaging  61s.  4d.  or  15  dwt.  per  ton.  The 
Robinson  has  had  to  cede  the  first  place  to 
younger  mines,  but  its  record  is  one  of  the 
glories  of  the   mining  industry. 


struis  yields  a  low-grade  ore  from  which  a  big- 
ger profit  can  be  won  in  the  larger  mill  of  the 
Roodepoort  United  than  in  its  own  small 
plant. 

The  raising  of  additional  capital  for  the 
Geduld  indicates  an  expansion  of  operations ; 
on  the  other  hand  the  decision  of  the  East 
Rand  Proprietary  to  cease  operations  at  the 
Angelo  Deep  points  the  other  way  and  will 
adversely  affect  the  Cinderella  Deep.  The 
increased  Modderfontein  dividend  cheered  the 
market  after  it  had  been  depressed  by  the 
passing  of  the  Durban  Deep  dividend. 


Company. 


Tons  crushed 


Value  of  gold 


Yield  per  ton 


Total  dividends 


City  and  Suburban 

Crown  Mines 

East  Rand  Proprietary 

Ferreira 

Ferreira  Deep 

Geldenhuis  Deep 

Langlaagte  Estate 

New  Primrose 

Nourse  Mines 

Randfontein  South 

Robinson 

Robinson  Deep 

Rose  Deep 

Simmer  &  Jack 

Village  Main  Reef 


3,661,020 
12,369,524 
10,054,414 
3,257,122 
1,995,393 
8,747.691 
6,483,071 
3,585,426 
3,852,641 
6,285,235 
4,801,075 
3,876.728 
5,351,613 
6,941,486 
4,529,260 


i 
6,617,300 

23,548,592 

17,260,212 
9,225,609 
5,603,074 

14,736,486 
9,637,597 
5,649,670 
7,636,291 
9,883,879 

14,730,170 
7,364,577 
8,420,995 

11,006,945 
9,403,847 


s. 
36 
38 
34 
56  8 
56  2 
33     8 


d. 
2 

1 
4 


29 
31 
39 
31 
61 


9 
6 
8 
5 
4 


38     0 
31     6 


31 
41 


9 
6 


i 
2,006, 
8,366 
4.977 
3.729 
2.570 
3.347 
2,594 
2.050 
1,676 
927 
8.199 
2.625 
2.143 
3,591 
2,251 


,913 
,235 
,967 
,250 
.750 
,014 
.105 
,025 
875 
500 
,688 
,186 
.125 
.461 
.143 


Up  to  July  1  the  total  dividends  declared 
by  companies  operating  on  the  Witwaters- 
rand  made  a  total  of  i:4,084,8 17,  with  ^159,439 
more  to  be  credited  to  outside  districts  of  the 
Transvaal.  Dividends  for  the  first  half  of 
1911  show  ten  decreases  and  four  increases, 
the  most  notable  being  Crown  Mines,  reduced 
from  65  to  55%,  and  Ferreira  from  150  to 
100%.  Among  the  increased  yields  are  those 
of  Knights  Deep,  New  Modderfontein,  Trans- 
vaal Estates,  and  Worcester.  Three  com- 
panies on  the  dividend  list  this  time  last  year 
have  failed  to  contribute,  while  two  new  names 
appear. 

A  further  consolidation  is  announced,  the 
Roodepoort  United  absorbing  the  Vogelstruis 
Estate,  and  thereby  gaining  172  claims.  This 
appears  to  be  an  excellent  move,  as  the  Vogel- 


Rhodesia.— The  output  of  gold  for  May, 
as  given  by  the  Chamber  of  Mines,  was  50,193 
ounces,  valued  at  /fi  11,413.  This  is  2353  oz. 
or  ^9883  less  than  April.  In  May  1908  the 
production  was  worth  ^^223,867;  in  May  1909, 
;^225,032  ;  and  in  May  1910,  ^224,888.  This 
indicates  how  little  real  progress  is  being  made, 
the  gain  by  individual  mines  being  balanced 
by  losses  at  others.  During  May  the  biggest 
return,  as  usual,  was  made  by  the  Cilobe  & 
Phoenix,  which  won  £r39,146  worth  of  gold 
from  5760  tons  of  ore.  The  production  from 
this  mine  has  been  well  maintained  since 
January  of  the  current  year.  Next  comes  the 
Giant  with  ^19,080  from  11,988  tons;  this 
being  almost  a  duplication  of  the  April  figures. 
The  Lonely,  Rezende,  and  Wanderer  e.vhibit 
decreases,  but  the  Willoughby  nearly  doubled 


THE    MIXING    MAGAZINE 


its  output,  to  ^11,830  from  8553  tons. 

It  is  reported  that  a  new  gold  area  is  being 
proved  in  the  Hartley  district ;  good  prospects 
have  been  disclosed  on  the  Turkais,  Oleander, 
and  Tea  claims.  The  formation  consists  of 
quartz  in  mineralized  schist  and  resembles  the 
Cam  &  Motor  lode.  The  London  and  Rho- 
desian  Co.  has  taken  an  option  on  the  Venice 
and  Subi  claims  in  the  Umsweswe  portion  of 
the  Hartley  district  and  is  now  engaged  in 
vigorous  exploratory  work.  From  the  Gwelo 
district  also  an  increase  of  activity  is  reported, 
especially  near  Hunter's  Road.  Several  Rand 
speculators  have  acquired  options.  In  the 
Enterprise  district  where  promising  tin  dis- 
coveries continue  to  be  made,  a  check  to  de- 
velopment has  been  offered  by  the  excessive 
prices  put  on  the  claims. 

Tanganyika  shareholders  have  been  cheered 
by  an  optimistic  cablegram  sent  by  Mr.  Robert 
Williams  from  Elisabethville.  He  states  that 
sufficient  ore  is  developed  to  yield  600,000 
tons  of  copper,  and  that  Mr.  Allan  Gibb's  re- 
ports impress  him  as  "  masterly."  This  mes- 
sage was  intended  for  the  family,  as  it  were ; 
it  expresses  the  undaunted  spirit  of  a  wonder- 
fully energetic  promoter,  but  is  not  at  all  con- 
vincing. We  have  read  some  of  the  reports 
of  Mr.  Gibb  and  far  from  being  "  masterly  " 
we  have  reason  to  consider  them  vitiated  by 
inexperience,  or,  to  be  precise,  lacking  the  ex- 
perience required  for  so  large  and  difficult  a 
problem  as  that  presented  by  the  metallurgy 
of  the  Tanganyika  ore  deposits.  Another 
message  from  Mr.  Williams  announces  the 
starting  of  the  first  blast-furnace.  Results 
will  soon  be  available. 

Two  Rhodesian  companies  make  an  initial 
dividend,  the  Selukwe-Columbia  paying  10% 
and  the  Gaika  5%.  The  Eldorado  Banket 
makes  an  interim  distribution  of  15%,  as  this 
time  last  year.  On  the  other  hand  the  yield 
of  the  Farvic  mine,  belonging  to  Rhodesia, 
Limited,  has  declined  seriously,  as  compared 
with  this  time  last  year ;  and  it  is  reported 


that  development  on  the  lower  levels  has 
proved  unsatisfactory. 

Dr.  Hans  Sauer  gave  an  interesting  sum- 
mary of  Rhodesian  mining  at  the  Explora- 
tion &  Development  Co.'s  meeting.  Of  the 
native  labour  employed  31%  is  engaged  in  de- 
velopment work.  This  affords  promise  of  an 
expanding  industry.  Among  the  mines  under- 
going development  are  at  least  a  dozen  that  are 
likely  to  make  a  mark,  such  as  the  Shamva, 
Arcturus,  and  Falcon. 

West  Africa.  —  The  returns  for  May 
showed  a  substantial  increase  in  the  production 
of  gold,  the  total  of  24,427  ounces,  worth 
;^96,409,  being  the  highest  since  May  1909, 
when  the  output  was  25,104  ounces,  worth 
;^100,056.  As  compared  to  April  the  gain  is 
^25,529.  For  the  first  five  months  of  this  year 
the  aggregate  production  is  89, 1 33  oz.  compared 
with  84,913  oz.  and  144,001  oz.  in  the  corres- 
ponding periods  of  1910  and  1909  respectively. 
The  recent  gain  is  to  be  credited  to  the  Pres- 
tea,  which  produced  £1^,121  worth  of  gold 
from  11,080  tons  of  ore.  Slightly  bigger  re- 
turns were  also  made  by  the  Broomassie  and 
the  Bibiani  mines.  The  Offin  river  dredges 
are  doing  better  and  those  on  the  Ancobra  will 
be  doing  so  when  the  re-organization  of  opera- 
tions has  been  completed  by  the  new  mana- 
ger. The  Ashanti  Goldfields,  of  course,  is 
still  the  largest  producer,  yielding  9585  oz. 
or  ;^4 1,625  from  9900  tons  in  May. 

The  Prestea,  Taquah,  and  Abosso  meetings 
left  a  good  impression.  The  work  of  re- 
organization appears  to  have  been  satisfac- 
torily completed.  The  Taquah  at  1650  feet 
shows  6. ft.  of  18  dwt.  ore,  and  it  is  a  curious 
fact,  not  unknown  in  mining,  that  the  original 
lode  which  '  petered  out '  at  the  9th  level  has 
been  found  to  be  overlapped  by  another  lode 
of  a  similar  character,  first  disclosed  by  a 
cross-cut  at  the  8th  level.  We  note  that  Mr. 
S.  J.  Weis,  the  new  manager  of  the  Ancobra 
Exploration  &  Dredging  Co.,  writes  most 
hopefully  concerning  that  undertaking,  having 


JULY,    1911 


tested  the  gravel  sufficiently  to  be  satisfied  of 
its  richness  in  gold.  A  bit  of  good  news  comes 
from  the  Taquah  Central,  which  has  struck  a 
foot  of  ounce  ore  at  400  feet.     This  may  not 
spell  profits,  but  it  is  distinctly  hopeful.    The 
Great  Fingall  has  an  interest  in  the  property. 
At  the  Adja  Bippo,  a  mine  belonging  to  the 
Wassau  Co.,  work  was  stopped  owing  to  a 
heavy  influx  of  water,  caused  by  unusual  rains 
at  the  end  of  May  ;  but  a  successful  effort  is 
being  made  to  unwater  the  mine  from  the  8th 
to  the  13th  levels. 


shaft  has  cut  the  vein  at  340  feet,  disclosing 
6  feet  of  ore  assaying  13  dwt.  per  ton.  Good 
news  continues  to  come  from  the  deep  work- 
ings of  the  Great  Fingall.  Mount  Lyell  is 
facing  labour  troubles,  owing  to  the  demands 
of  the  engine-drivers.  It  is  likely  that  the 
Hercules  and  Primrose  mining  companies  at 
Mount  Read  in  Tasmania  will  be  amalga- 
mated with  the  Tasmanian  Smelting  Co.  of 
Zeehan.  Mr.  E.  A.  Wemberg  is  promoting 
the  scheme.  The  strike  announced  from  the 
British  Broken  Hill  Proprietary  is  important. 


A  year  ago  much  was  heard  of  the  banket  .f  confirmed  by  actual  development  work    The 

deposits  belonging  to  the  WalHs  Syndicate,  drill-holes  have  pierced  an  orebody  parallel  to 

situated  about   60  miles  east  of  -the  Ashanti  the  mam  lode,  but  the  shape  of  it  is  vet  to  be 

Goldfields  concessions.     The  report  now  is-  ascertained,  the  distance  between  the  outside 

sued  records  that  seven  shafts  have  been  sunk  bores  being  500  feet.     The  width  of  ore  dis- 

at  the  South   Reef  Main  Camp  to  depths  of  closed  is  magnificent,  but  it  mav  prove  a  flat 

67  to  108  ft.  and  that  640  ft.  of  driving  has  lens. 


been  done.  Quite  unexpectedly  the  lode  has 
been  found  to  be  much  broken  and  faulted,  so 
that  it  has  been  difficult  to  estimate  its  value. 
Such  sampling  as  can  be  done  reliably  shows 
contents  varying  from  3  to  16  dwt.  over  widths 
from  30  to  130  inches.  It  is  intended  to  con- 
tinue sinking  at  two  shafts  in  the  hope  that 
the  lode  will  be  less  faulted  and  broken  at 
depth. 

India. — We  refer  elsewhere  to  the  flota- 


Mexico. — Our  correspondent  sends  an  in- 
teresting letter.  The  town  of  Zapotlan  was 
partly  destroyed  by  an  earthquake  on  June  7. 
Order  is  being  generally  restored  after  the 
revolution.  The  chief  event  of  the  month  re- 
lates to  the  Camp  Bird  company,  which  pro- 
poses to  issue  preference  shares  in  lieu  of  the 
existing  debentures.  This  is  a  wise  move. 
The  latest  estimates  give  ^7 1,720  as  the  pro- 
fit remaining  in  the  old  Camp  Bird  mine,  in 


tion  of  the  Jibutil  Gold  Mines  of  Anantapur.      Colorado,  and  ^1,793,000  in  the  Santa  Ger 


The  latest  news  of  its  parent  company,  the 
Nundydroog,  shows  that  at  the  2600  ft.  and 
2750  ft.  levels  in  Kennedy's  section  several 
points  are  developing  ore  carrying  from  1  to 
2i  oz.  over  widths  of  1*  to  2h  feet.  This 
mine  has  fully  maintained  the  improvement 
that  has  been  a  conspicuous  feature  of  the 
Kolar  goldfield  during  the  last  year  or  two. 
On  the  other  hand  the  developments  at  the 
Ooregum  continue  to  be  rather  disappointing. 


trudis,  at  Pachuca.  This  includes  the  ore 
100  ft.  below  the  18th  level.  Earnings  from 
the  Santa  Gertrudis  are  expected  to  be 
^245,900  for  the  first  year  and  ;^368,852  for 
the  second. 

United  States.— The  talk  of  a  copper 
merger  has  quieted.  In  face  of  recent  de- 
cisions of  the  Supreme  Court  it  would  be 
dangerous  to  promote  any  combination  to  con- 
trol the  price  of  the  metal ;  and  unless  that 


as  the  lodes,  though  containing  one  ounce  ore,  were  done  by  curtailing  production,  what  good 

are  only  from  six  to  nine  inches  wide.  would  a  merger  do  ?     Sixteen  American  cop- 

AUSTRALASIA. — A  good  rainfall  is  reported  per  companies,  including  those  operating  in 

at  Kalgoorlie.     The  Bullfinch  wild-cats  are  South  America,  plan  to  increase  their  aggre- 

making  a  miserable  showing.     The  Yuanmi  gate  output  by  about  150,000  tons  per  annum. 


THE    MINING    MAGAZINE 


We  publish  an  abstract  of  the  Utah  Copper 
Co.'s  annual  report.  Good  news  comes  from 
Jarbidge,  one  of  the  new  gold-mining  dis- 
tricts of  Nevada. 

The  Tomboy  Gold  Mines  Co.  has  issued  a 
circular  announcing  the  acquisition  of  the  Re- 
venue Tunnel  mines,  which  have  been  in- 
spected by  the  manager,  Mr.  D.  A.  Herron, 
whose  favourable  opinion  was  confirmed  by 
Messrs.  P.  L.  Foster  and  R.  M.  Raymond. 
A  sum  of  $400,000  is  to  be  paid  for  mining 
claims  having  an  ore  reserve  estimated  at 
137,914  tons,  of  a  gross  value  of  $1,036,297, 
leaving  a  net  profit  of  $415,000.  This  is  good 
business,  and  does  credit  to  the  Exploration 
Company. 

Canada.  —  The  prosperity  of  the  Mond 
Nickel  Co.,  which  produces  nickel  and  copper 
sulphate  from  Sudbury  ores,  continues  un- 
abated. Owing  to  the  demand  for  nickel  the 
directors  are  about  to  erect  a  new  smelter,  and 
for  this  purpose  have  offered  ;^250,000  5%  de- 
bentures for  subscription.  It  will  be  remem- 
bered that  when  the  company  started  1 1  years 
ago  the  refining  process  gave  much  trouble, 
but  since  the  process  was  perfected  the  profits 
have  gradually  increased  until  during  the  last 
financial  year  the  ordinary  shareholders  re- 
ceived 164%.  The  debentures  were  readily 
absorbed. 

Porcupine  can  now^  be  reached  by  rail. 
Many  speculators  are  likely  to  avail  them- 
selves of  the  opportunity.  Interest  m  the 
goldfield  continues  unabated.  It  is  stated  that 
the  block  of  Hollinger  shares,  namely  44,000, 
acquired  by  the  Northern  Ontario  Explora- 
tion Co.,  has  been  sold  in  New  York  and 
Toronto.  As  these  shares  were  bought  at 
$5  and  were  sold  between  $10  and  $15,  up 
to  $16'15,  the  company  must  have  made  a 
handsome  profit,  about  $350,000.  Also  a 
block  of  30,000  shares  held  by  a  brokerage 
house  in  London  has  been  sold.  This  accounts 
for  the  drop  to  $1375  or  £l.  17s.  London 
did  well  on  Hollingers.  Meanwhile  the  shares 


of  the  Porcupine  Development  Co.,  the  sub- 
sidiary of  the  Northern  Ontario  Co.,  are  being 
offered  for  sale  in  Canada.  At  Toronto  and 
Montreal  the  wild-cats  seem  more  in  favour 
with  speculators  than  the  real  mines,  whose 
shares  are  so  high  now  as  to  discount  favour- 
able developments.  Another  fire,  this  time 
on  the  Dome  Extension  claims,  has  caused 
the  death  of  15  men.  Rich  ore  has  been  found 
in  the  North  Dome  shaft  at  a  depth  of  34  ft., 
and  the  same  orebody  has  been  cut  by  a  drill 
at  150  ft.,  the  ore  showing  free  gold.  This 
ground  lies  between  the  Foley  O'Brien  and 
the  Timmins  claims. 

Cornwall.  —  The  speeches  of  Messrs. 
Francis  Allen  and  Josiah  Paull  at  the  South 
Crofty  meeting  reported  elsewhere  in  this 
issue  strike  a  decidedly  cheerful  note,  and 
we  congratulate  the  chairman,  engineer,  and 
shareholders  on  the  thoroughly  businesslike 
manner  in  which  this  old  tin  mine  is  now 
managed.  It  is  not  often  that  the  manager 
of  a  Cornish  mine  can  say  that  he  has  enough 
ore  developed  to  last  for  three  years,  and  it  is 
seldom  that  regular  quarterly  dividends  at  the 
rate  of  20%  per  annum  are  paid  by  Cornish 
mines,  and  at  the  same  time  large  sums  put 
by  as  reserve.  Of  course  the  mine  is  finan- 
cially favoured  by  the  present  high  price  of 
tin  and  wolfram,  but  that  does  not  affect  the 
main  point,  which  is  that  costs  are  carefully 
scrutinized, developmentsare  pushed  far  ahead 
of  the  mill,  and  mining  and  concentration 
operations  conducted  on  modern  principles. 

We  also  refer  briefly  to  the  re-arrangement 
of  control  and  management  at  the  Cam  Brea 
&  Tincroft.  Here  the  chief  '  lord,'  Viscount 
CHfden,  is  taking  a  keen  and  direct  interest  in 
the  work,  and  through  his  influence  new  blood 
has  been  introduced  on  the  technical  staff. 
We  believe  that  Mr.  Edward  S.  King  and  his 
assistant,  Mr.  H.  Swan  Edgar,  will  in  the 
course  of  time  raise  the  mine  from  its  present 
stagnant  condition  and  put  it  on  a  profit-earn- 
ing basis. 


JULY,    1911 


STATISTICS 

Stocks  of  Copper  in  England  and  the  Continent. 
Reported  by  Henry  R.  Merton  &  Co. 


April  29 
Tons 

May  31. 
Tons 

June  30 
Tons 

61,563 
6,080 
2,925 

57.557 
6,081 

-?  700 

55,579 

In  Prance       

5,843 

Aflnat  from  Chile             .•■■ 

1,500 

Afloat  from  Australia 

7,500       1        6,775 

7,250 

Total                      

78  068       '       72  613              70,172 

Tn  Rotterdam 

7,200                 7,250                 7,200 

In  Hamburg  (estimated)... 

9,500              10,500              10,100 

Production  of  Gold  in  Rhodesia. 


American 

Copper  Producers'  Association 
In  Tons  of  2,240  lb. 

Produc- 
tion. 

Deliveries 

Stocks  at 

Domes- 
tic 

Foreign 

Total 

end  of 
month 

Tanuarv  1911 

51,650 
49,030 
58,273 
52,716 
56.679 
55.605 

18,785 
22,553 
29,500 
23,395 
28,814 
27,525 

23,753 
20,139 
26,375 
27,736 
27,669 
31,902 

42,538 
42.692 
55,875 
51,132 
56,483 
59,427 

63,591 

February    

March     

69,929 
72,325 

April          

73,909 

74,105 

June 

70,283 

Production  of  Gold  in  the  Transvaal. 


Rand 


July,  1910 

August  

September   

October 

November    

December 

Totals,  1910 

January  1911 

February  

March 

April  

May     

June    


Oz. 

610,664 
623.129 
621.311 
627.445 
617,905 
616,668 


Else- 
where 


7,228,588 

625,862 
585,683 
649,247 
638,421 
658,196 
657.023 


Oz. 

28.050 
26,140 
25,588 
25,702 
24,686 
24,327 


305,532 

25,201 
24,965 
26,818 
29,293 
27.755 
27.544 


Total 


Oz. 

638,714 
649,269 
646,899 
653,147 
642,591 
640,995 


7,534,120 

651,027 
610,828 
676,065 
667,714 
685,951 
684,567 


Value 


£ 

2,713,083 
2,757,919 
2,747,853 
2.774,390 
2,774,390 
2.722.775 


32.002,912 

2,765,386 
2,594,634 
2.871,740 
2.836,267 
2,913,734 
2,913,734 


Cost  and  Profit 

ON 

THE 

Rand. 

Month. 

Tons 

Yield 
per  ton 

Costs 
per  ton 

Profit 
per  ton 

Total 
profit 

October  1910  ■•• 

November  

December 

January  1911... 
February       .  . 

1,868,718 
1,800.371 
1,827,423 
1,865,232 
1,712,198 
1,960.678 
1,926,583 
2,002,926 

s. 
28 
28 
28 
28 
28 
27 
27 
27 

d. 

0 
6 

1 
0 
6 
7 
7 
6 

s. 
17 
18 
17 
17 
18 
17 
17 
17 

d. 
9 
0 
9 

11 
3 

11 
6 

10 

s. 
10 
10 
10 
10 
10 

9 
10 

9 

d. 

5 
1 
3 
9 
1 
7 

£ 

952,161 
951,773 
952,574 
930,059 
874,612 

March  

949,415 

April 

971,858 

May 

956.823 

Totalsandaver- 

ages  for  1909.. 

Ditto  1910 

20.543.759 
21.432.541 

28 
28 

11 
6 

17 
17 

1 
7 

11 
10 

6 
6 

11,794,376 
11,216.105 

Natives  Employed  in  the  Transvaal  Mines. 


January  31.. 
February  28 
March  31  ... 

April  30 

May  31  

June  30 


Gold 
mines 


183.268 
189,434 
193,457 
194,328 
190,392 
186.940 


Coal 
mines 


8,357 
8,513 
8,493 
8.511 
8.379 
8.212 


Diamond 


9.991 

9,814 
10,061 
10,272 
10,425 
10,597 


Total 


201,616 
207,761 
212.011 
213,111 
209,196 
205,749 


Gold  Output  of  India. 

Year  1909 

Year  1910 

June  1911 

1911  to  date 

£2,083,901 

£2,104,858 

£177,498 

£1,052.322 

Month. 

1908 

1909                1910 

1911 

£ 

199,388 
191,635 
200,615 
212,935 
223,867 
224,920 
228,151 
230.792 
204.262 
205.466 
196.668 
217.316 

£ 

204.666 
192.497 
202.157 
222.700 
225,032 
217,600 
225.234 
228.296 
213.249 
222.653 
236.307 
233,397 

£ 
227,511 
203,888 
228.385 
228,213 
224.888 
214.709 
195.233 
191.423 
178.950 
234.928 
240.573 
199.500 

£ 

207  903 

February  

203,055 
231  947 

221,296 

^ay 

211  413 

July 

— 

September  ... 

October 

November 

December..  . 

— 

Totals 

2,526,007 

2,623.788 

2.568.201 

— 

Production  of  Gold  in  West  Africa. 


1909 

1910 

1911 

Month. 

Oz. 

Value 

Oz. 

Value 

Oz.        Value 

January  

February    .. 

22.817 
21,403 
23,186 
21,491 
25,104 
17,340 
17,331 
17,766 
18,125 
15,957 
17.882 
17.570 

£ 
91.112 
86,210 
93.556 
88,071 
100,056 
70,561 
70,523 
71,614 
72,963 
65,813 
73,824 
71,332 

17.357 
16,976 
17,627 
16,363 
16,590 
17,194 
15,564 
13,921 
11,497 
13.341 
14,021 
15,042 

£ 

70,699 
68.469 
71,954 
67,069 
68,355 
70,988 
58,551 
57,713 
47,746 
55,046 
57,658 
61.737 

15.903 
15,179 
16.387 
17.237 
24.427 

£ 

66.107 
63.081 
67.673 

70.880 

May 

96.409 

Tulv  



September... 

October  

November ... 
December  ... 

— 

235.972 

955,635 

185,493 

755,985 

— 

— 

Production  of  Gold  in 

Wester> 

Australia. 

Month. 

Export 
oz. 

Mint 
oz. 

Total 
oz. 

Total 
value 

Total,  1910  

363,496 

1,209.856 

1.573.352 

£ 

6.682.042 

lannarv  1911        

17,463 
22,047 
12,296 
20.455 
22.076 
10.523 

102.035 
84.991 
93.267 
91,791 
88,952 

106.464 

119,498 
107.038 
105.563 
112.246 
111.028 
116,987 

507.592 

454,666 

March                

448,426 

476,787 

471.615 

June 

497.188 

Sale  of  Tin  Concentrate  at  Redruth  Ticketings. 


Apri 
May 
May 
May 
June  12. 
June    26. 


18.  1911. 

1.  ..  . 
15.  ..  . 
29,      „    . 


Tons 


199i 

260 

218t 

27l4 

22l5 

2694 


Value 


£23.694 
£30.313 
£25,714 
£31.558 
£26.403 
£31.399 


Average 


£118  18 
£116  11 
£117  13 
£U6    4 

£|19  1 
£116  10 


Exports  of  Tin  and  Ore  from  Straits  and  Bolivia. 
Reported  by  A.  Strauss  &  Co. 


Metal  from  Straits  lo  Europe 
and  America   

Metallic  Content  from  Bolivia 
to  Europe 


May.  1911 
tons 

4290 

1657 


June.  1911 
tons 

5.060 

2,056 


1911  to  date 
tons 

25.562 

10.673 


EDITORIAL 


UNDER  "  Discussion"  we  publish  a  pro- 
test against  the  vague  wording  of  adver- 
tisements intended  to  secure  the  services  of 
technical  men  for  appointments  abroad.  We 
do  not  agree  with  our  correspondent's  closing 
remark,  however  ;  obviously  a  fair  contract 
should  involve  an  equal  exchange  ;  therefore 
salary  should  be  proportioned  to  the  experience 
and  skill  required.  Companies  needing  men 
ought  to  give  adequate  information,  so  that 
misunderstanding  may  be  avoided. 


mark  the  third  quarter,  for  the  holiday  season 
checks  activity,  but  the  last  portion  of  the 
year  ought  to  be  lively. 


PORCUPINE  is  likely  to  gain  by  a  visit 
from  a  thoroughly  representative  group  of 
operators  and  engineers.  On  July  8  the  fol- 
lowing gentlemen  sailed  for  New  York  on  their 
way  to  the  new  goldfield  in  Northern  Ontario  : 
Messrs.  L.  Reyersbach,  H.  F.  Marriott,  C. 
Algernon  Moreing,  W.  J.  Loring,  and  G.  A. 
Prentice.  There  is  enough  money  and  brains 
here  represented  to  run  a  South  American  re- 
public. One  thing  they  cannot  do,  and  that  is 
to  make  a  gold  mine ;  but  they  know  how  to  buy 
one  and  they  know  how  to  operate  it  on  the 
most  approved  technical  principles.  To  go  to 
Canada  at  this  season  is  a  pleasure  in  itself  ; 
we  trust  that  the  visit  of  these  gentlemen  may 
prove  profitable  also. 


ACCORDING  to  The  Economist  the 
applications  for  new  capital  during  the 
first  half  of  the  current  year  reached  a  total 
of  ;^117,483,800,  as  against  ^118,077,000 
during  the  corresponding  period  last  year,  and 
;^121,073,600  in  1909.  Last  year  began  with 
a  lusty  oil  and  rubber  boom,  and  the  revival 
of  world-wide  trade  also  stimulated  specula- 
tion. This  year  conditions  have  been  healthy 
rather  than  feverish.  The  Coronation  tended 
to  restrict  business  in  the  second  quarter ;  it 
is  not  likely  that   a   rush   of  new   issues  will 


THE  KERN  RIVEROilfieldshasproved 
a  sorry  fiasco,  culminating  in  an  angry 
meeting  of  shareholders.  As  far  as  we  can 
learn  the  trouble  is  traceable  to  two  familiar 
defects  in  company  flotation,  namely,  over- 
capitalization and  lack  of  adequate  indepen- 
dent technical  advice.  The  Californian  own- 
ers probably  received  as  much  as,  if  not  more 
than,  the  oil-lands  were  worth,  but  the  enter- 
prise was  handicapped  by  the  excessive  burden 
imposed  upon  it  by  sanguine  promoters.  The 
engineers  who  made  the  reports  are  not  known 
to  us.  Their  report  was  made  for  the  vendor 
syndicate.  The  directors  themselves  appear 
to  be  novices  in  oil  exploitation.  The  prospec- 
tus was  over-loaded  with  the  names  of  bankers 
and  brokers.  When  will  the  public  realize 
that  the  success  of  a  mining  company  depends 
upon  unprejudiced  advice  and  experienced 
management  ? 


DE  BEERS  and  Premier  quotationsought 
to  have  risen  by  reason  of  the  display 
made  on  the  occasion  of  the  gala  performance 
at  the  Opera.  A  mining  engineer  who  was 
present  informs  me  that  his  eyes  suffered  as 
from  snow  blindness.  The  finest  showing 
was  made  by  the  Maharajah  of  Patiala,  whose 
manly  breast  scintillated  in  a  manner  to 
remind  Macaulay's  schoolboy  of  the  spolia- 
tion of  Oude.  Another  gorgeous  person  was 
a  Mrs.  Vanderbilt  who  did  credit  to  the 
splendours  of  New  York's  smart  set.  Indeed 
the  scene  was  so  remarkable  that  the  audience 
became  as  interesting  to  those  on  the  stage 
as  the  performers  were  to  the  spectators. 
We   are   reminded    of    Cecil    Rhodes,    who, 


JULY,  1911 


when  presiding  at  a  De  Beers  meeting,  said 
that  as  long  as  women  were  vain  and  men 
were  foolish  the  shareholders  would  be  as- 
sured of  dividends  from  the  mines  at  Kim- 
berley.  An  enterprise  that  depends  more  on 
human  frailty  than  on  the  vagaries  of  lode 
formation  is  in  an  unusually  strong  position. 


ON  JUNE  29  the  new  quarters  of  the 
Mining  and  Metallurgical  Club  at  No.  3 
London  Wall  Buildings  were  formally  opened 
by  a  luncheon,  which  was  well  attended  and 
well  served.  In  the  unavoidable  absence  of 
the  president,  Mr.  Sidney  Farrar,  the  chair 
was  taken  by  the  vice-president,  Mr.  Walter 
McDermott,  who  made  an  appropriate  speech, 
not  without  humorous  reference  to  the  '  deep- 
level  '  of  the  rooms  in  which  members  can  now 
satisfy  the  needs  of  nourishment.  Mining  en- 
gineers naturally  try  to  get  '  on  the  ground- 
floor  '  in  such  financial  dealings  as  the  niceties 
of  professional  propriety  permit,  and  if  they 
find  themselves  advantageously  placed  on  the 
sub-ground  floor,  so  much  the  better.  Un- 
doubtedly they  like  it.  And  the  members  of 
the  Club  also  congratulate  themselves  on  their 
secretary.  This  was  shown  by  the  hearty  ap- 
plause that  greeted  the  presentation  of  a  cigar- 
ette case  to  Mr.  Charles  McDermid,  from  the 
committee,  the  members  of  which  have  good 
reason  to  appreciate  the  invaluable  assistance 
given  by  him  in  the  organization  and  estab- 
lishment of  the  Club.  To  Mr.  Farrar  and  to 
Mr.  McDermid  the  most  cordial  appreciation 
is  due,  and  is  willingly  accorded.  They  can 
feel  proud  of  the  results  achieved.  The  Min- 
ing and  Metallurgical  Club  is  now  a  pleasant 
fact  and  we  hope  it  may  prosper  exceedingly. 


WE  FEEL  SORRY  for  the  gentlemen 
on  the  staff  of  the  Kyshtim  Corpora- 
tion if,  as  we  are  reliably  informed,  they  were 
guilty  of  gross  inhospitality  to  three  engineers 
who  came  on  a  visit  to  their  mine  and  smelter. 
The  story  is  that  some  of  the  Kyshtim  people 


had  visited  the  Syssert  estate,  where  they  had 
been  well  received  both  as  regards  technical 
information  and  creature  comforts.  On  re- 
ceipt of  several  invitations  the  three  gentle- 
men from  the  Syssert  went  to  the  Kyshtim 
where  they  got  a  greeting  something  in  this 
wise  :  "  Glad  to  see  you,  but  your  train  starts 
soon;  here's  your  hat."  This  necessitated  a 
return  journey  of  80  miles  by  sleigh  within  24 
hours  and  in  a  temperature  of  —  40°  F.  Several 
weeks  later  it  transpired  that  the  directors  of 
the  Kyshtim  had  issued  an  order  prohibiting 
entry  into  the  smelter  or  access  to  the  stopes. 
We  thought  the  Kyshtim  was  a  fine  mining 
enterprise,  cleverly  financed,  well  managed, 
and  in  the  hands  of  first-rate  technical  men. 
What  is  there  to  hide  ? 


RECENT  FLOTATIONS  include  the 
Jibutil  Gold  Mines  of  Anantapur  (in 
Madras),  a  subsidiary  of  the  Nundydroog  com- 
pany and  under  the  direction  of  John  Taylor 
&  Sons.  Reports  by  experienced  managers  of 
Indian  gold  mines  are  furnished,  and  reason- 
able conditions  of  purchase  appear  to  have 
been  arranged.  Preliminary  mining  work 
indicates  that  the  prospects  justify  operations 
on  a  larger  scale.  This  is  a  creditable  bit  of 
mining  business.  On  the  same  day  the  pros- 
pectus of  the  Mawchi  Tin  and  Wolfram  Mines 
made  its  appearance.  This  is  a  subsidiary  of 
the  Southern  Shan  States  Syndicate,  which 
is  represented  on  the  board  of  directors  by 
Messrs.  R.  Phipps  Hornby  and  P.  Wighani 
Richardson.  Participation  by  the  Hirsch  Syn- 
dicate and  the  Consolidated  Gold  Fields  of 
South  Africa  is  indicated  by  the  directorships 
allotted  to  Messrs,  F.  W.  Baker  and  H.  D. 
Boyle,  respectively.  The  board  is  strengthened 
by  the  addition  of  a  mining  engineer  in  the  per- 
son of  Mr.  R.  Oilman  Brown,  who  will  be  of 
great  help  to  his  co-directors.  An  excellent  re- 
port by  Mr.  H.  L.  Twite  constitutes  the  basisof 
the  flotation.  Several  veinscontainingtinoxide 
and  wolfram  have  been  tested  and  sampled 


10 


THE    MINING   MAGAZINE 


sufficiently  to  justify  further  developments, 
with  anticipation  of  profitable  operations.  The 
only  criticism  we  care  to  make  relates  to  the 
manner  of  raisingcapital;  this  isdone  by  means 
of  debentures.  While  convenient,  it  is  not  a 
method  suitable  to  minmg,  the  essential  basis 
of  which  is  a  fluctuating  asset.  Debentures 
are  more  appropriate  to  investments  of  a  less 
speculative  character,  such  as  possess  assets 
having  a  realizable  value  in  case  of  foreclosure. 
In  short,  debentures  are  little  suited  to  the  ups 
and  downs  of  mining  speculation. 


Rand  Economics. 

The  financial  supplement  of  The  Times  re- 
cently has  contained  a  series  of  articles  on  the 
mining  industry  of  the  Witwatersrand,  view- 
ing the  subject  as  it  appeals  to  the  British 
shareholder.      Such  articles  in  a  newspaper 
that,  despite  its  recent  changes,  is  still  the 
leader  of  the  world's  Press,  are  sure  to  be  in- 
teresting to  those  engaged  in  mining.     They 
also  provoke  our  criticism,  for  a  daily  news- 
paper rarely  touches  a  subject  so  technical  as 
mining  without  making  palpable  errors,  which 
have  the  merit,  at  least,  of  putting  in  print  the 
mistaken  notions  current  among  persons  who 
speculate  in  mining  shares.     The  articles  in 
The  Times  are,  of  course,  excellent  in  tone  and 
manner;  they  appear  to  have  been  written  by 
one  who  is  familiar  with  recent  writings  on 
the  subject,  but  they  indicate  the  amateur  in 
mining.    Thus  the  first  paragraph  begins  with 
an  elementary  fallacy  :  "  The  question  of  the 
lodes  giving  out,  which  is  the  bogey  of  most 
mining  concerns,  does  not  exist  for  the  Wit- 
watersrand, for,  though  the  ore  of   the  reef 
varies  in  value,  there  is  no  doubt  that  it  exists 
in  payable  grades  and  in  large  quantities  down 
to  any  depth  at  which  it  may  be  practicable  to 
mine  it."     Here  we  have  one  of  the  supposi- 
tions that  has  vitiated  Rand  finance  and  de- 
luded thousand  of  shareholders.     Our  techni- 
cal readers  know  and  our  non -technical  readers 
may  be  informed  categorically,  first,  that  all 


lodes    of   gold-bearing   ore    become    poor    in 
depth,  and,  second,  that  the  skill  of  man  suf- 
fices to  penetrate  the  earth  deeper  than  any 
ore  as  yet  discovered.     A  lode  is  "practicable 
to  mine  "  as  long  as  it  continues  rich  enough 
to  yield  a  profit  ;   the  limit  to  mining  on  the 
Rand  is  already  recognized,  the  ore  becoming 
poorer  in  depth   until  a  horizon  is  reached  at 
which  the  yield  will  not  suffice  to  pay  the  cost, 
which  includes  not  only  the  bare  expense  of 
extraction  but  also  interest  on  the  capital  in- 
volved,  more  particularly   during   the    many 
years    consumed   in   sinking    shafts,  building 
mills,  and  other  necessary  preparations.     It  is 
true  that  "  the  reef,"  that  is,  the  beds  of  con- 
glomerate containing  gold,  does  persist  to  a 
great  depth,  but  this  fact   has  no  economic 
significance   if   the  proportion  of  gold  is  too 
small  to  defray  all  the  cost.     There  is  gold  in 
sea-water ;  that  does  not  make    the  ocean  a 
mine.     On  the  other  hand  it  is  a  fact  that  the 
ore  of  the  Main   Reef  series  has  been  found 
to  be  subject  to  variations,  irregularities,  and 
breaks  comparable  to  those  of  veins  elsewhere 
and  it  is  now  known  that  the  supposed  abnor- 
mal uniformity  of  the  banket  is  a  delusion  and 
a  snare.     The  unusual  size  of  the  properties, 
and  the  enormous  scale  on  which   they  are 
operated,    has    tended    to    obscure    the    local 
variations  and  the  sporadic  distribution  of  the 
gold.     It  may  be  allowed    that,  taken   as  a 
whole,  the  Rand  possesses  ore  deposits  of  an 
extent   and    homogeneity    unknown  in  other 
regions,  but  it  is  fair  to  add  that  these  charac- 
teristics have  been  exaggerated  to  an  assump- 
tion of  uniformity  highly  prejudicial  to  sound 
economics. 

When  the  writer  in  The  Times  proceeds  to 
explain  "why  investors  are  shy"  of  the  Kaffir 
market,  he  is  well  within  his  own  province.  It 
is  due,  he  says,  to  the  fact  that  "  the  manage- 
ment of  the  mines  is  in  the  hands  of  persons 
who  are  known  to  speculate  largely  in  their 
shares,  and  in  fact,  to  rely  on  that  speculation 
as  a  principal  means  of  livelihood."   He  refers 


JULY,    1911 


11 


to  the  '  group  '  control.      But  he  only  touches 
the  fringe  of  the  matter,  evidently  realizing 
that  he  is  on  dangerous  ground.  We  are  frank- 
to  say  that  he  would  have  done  better  service 
by  elucidating  this  problem  than  by  dabbling 
in  technical  affairs  beyond  his  ken.     For  here 
is   the  crux.     The  mining  companies  of  the 
Rand  are  controlled  by  six  or  seven  groups  of 
capitalists  who  direct   the    financial  and  the 
technical  operation  of  about  75  different  mines. 
Each  group  has  its  own  holding  company  and 
deals  in  shares  for  profit.     The  difficulty  is  to 
reconcile  the  interest  of  the  holding  company 
with  that  of  shareholders  in  the  various  min- 
ing companies  operating  under  the  control  of 
the  former.     Again,  the  holding  company  may 
be  directed  by  a  firm  or  by  an  inner  clique  of 
clever  capitalists.     Can  divergent  interests  be 
so  considered  as  to  give  the  average  share- 
holder a  fair  run  for  his  money,  especially  in 
the  subordinate  companies,  the  shares  of  which 
afford  the  holding  company  every  chance  for 
well-informed  speculation  ?      In  the  main  it  is 
recognized  that  honesty  is  the  best  policy  and 
an  effort  has  been  made  to  give  each  holding 
company  a  reputation  for  fair  dealing.    Some 
lapses  are  recorded  and  public  confidence  has 
suffered,    but,    having    regard    to    the    power 
willingly  given  by  speculators  to  the  groups,' 
It  is  only  fair  to  admit  that  opportunities  for 
chicanery  have  been  rarely  accepted.     After 
all,  the  public  knows  how  the  mines  are  con- 
trolled and  they  know  that  the  holding  com- 
panies buy  and  sell  shares  in  various  mines ; 
if  then,  they  disapprove  of  the  system,  they 
should  not  participate  in  the  dealings  resulting 
from  it.     We  confess  that  for  the  moment  we 
see  no  alternative  to  the  'group  '  system, which 
resulted  from  the  necessity  for  providing  enor- 
mous slices  of  capital  for  the  development  and 
equipment    of    the  mines    in    the  Transvaal. 
Naturally  those  who  found  the  money,  and 
assumed  the  first  risk,  also  expected  the  con- 
trol of  the  business.     It  was  to  their  interest 
subsequently  to  diminish  that  risk,  while  re- 


taining full  control,  by  selling  shares,  at  a  pro- 
fit, to  the  public.     In  some  cases  the  transac- 
tion failed  to  be  sound  business, in  that  it  was 
not  mutually  profitable,  but,  on  the  whole,  it 
is  to  the  recklessness  and  greed  of  the  public 
rather  than  to  any  deception  on  the  part  of  the 
controllers  that  we  must  debit  the  disappoint- 
ments incidental  to  speculation  in  Rand  shares. 
Of   the   three   articles  in    The    Times,  the 
last  two  and  a  part  of  the  first  are  devoted  to 
the  labour  problem,  indicating  that  the  writer 
has  a  correct  idea  of  the  relative  importance 
of  this  aspect  of  his  enquiry.     Undoubtedly 
the  working  of  lower  grade  ore  on  an  extend- 
ing scale  was  based  on  the  supposition  that 
greater  tonnage  would  yield  not  only  lower 
cost,  which  is  secondary,  but  a  larger  profit, 
which  is  the  primary  purpose  of  mining.  More- 
over a  lowering  of  the  average  grade  tended 
to  obscure  the  slow  but  decisive  impoverish- 
ment in  depth  and  it  was  a  policy  calculated 
to  lengthen  the  lives  of  the  mines.      In  every 
way  it  was  a  correct  policy.     But  it  assumed 
a  practically  unlimited  supply  of  labour.     This 
has   not   been    forthcoming.       Despite   wide- 
spread recruiting   and  higher  wages,   it   has 
been  found  impossible  to  obtain  all  the  natives 
required.     Even   the   average   efficiency  has 
been    lowered    by    indiscriminate    recruiting. 
Competition   for  labour   threatens    to  create 
another  difficulty.     Some    mines    have  been 
compelled  to  close-down,  but  new  ones  are 
starting  and  several  big  properties  are  in  pro- 
cess of  preparation  for  operations  that   will 
demand    large   numbers  of  workmen.      The 
writer  of  The  Times  says  that  "  the  control- 
ling houses  have  as  yet  shown  no  sign  that 
they  are  alive  to  the  situation.     Possibly  the 
public  sees  further  ahead,  and  its  realization 
of  what  must  be  considered  an  inherent  weak- 
ness in   the  situation  has  combined  with   its 
distrust  of  the  'controls'  to  produce  the  pre- 
sent unpopularity  of  the  Kaffir  market."     Of 
course,  the  '  houses  '  are  deeply  aware  of  the 
facts  and  equally  of  course  the  public  sees 


12 


THE    MINING    MAGAZINE 


them  only  as  through  a  glass  darkly.  It  needs 
no  subtle  guessing  to  conclude  that  the  in- 
creasing tendency  toward  consolidation  of  pro- 
perties is,  in  part,  due  to  a  recognition  of  the 
necessities  of  the  situation.  If  the  supply  of 
labour  be  inadequate  for  all  the  mines,  obvi- 
ously it  were  better  to  work  those  that  are 
most  profitable.  When  the  latter  are  ex- 
hausted and  the  labour  supply  becomes  super- 
abundant, it  will  be  economical  to  exploit  the 
poorer  mines  on  a  scale  even  bigger  than  any 
contemplated  at  present.  Let  amalgamation 
proceed  until  the  less  profitable  mines  are 
amalgamated  out  of  existence,  to  be  treated 
as  a  deferred  reserve  for  realization  when 
conditions  warrant. 


Great  Fingall. 

The  annual  meeting  of  the  Great  Fingall 
Consolidated  was  rendered  noteworthy  by 
good  news  concerning  recent  developments. 
Mr.  C.  Algernon  Moreing,  the  chairman,  gave 
a  lucid  account  of  the  later  history  of  the 
mine  and  the  manner  in  which  a  good  pros- 
pect has  been  found  in  the  deeper  workings 
after  passing  through  a  poor  zone.  This  af- 
fords an  excellent  example  of  intelligent  ex- 
ploration guided  by  geological  evidence.  The 
engineers  of  Bewick,  Moreing  &  Co.  had 
started  the  work  and  carried  it  to  the  point 
of  fulfilment  when  Mr.  Malcolm  Maclaren 
was  engaged  to  make  a  geological  investiga- 
tion. His  report,  dated  October  22,  1910, 
endorses  the  policy  of  the  management  and 
gives  scientific  data  for  the  belief  that  deeper 
search  for  fresh  ore-bearing  ground  is  justi- 
fied. It  will  be  remembered  that  the  last  of 
the  big  stopes  in  the  Great  Fingall  was  on 
the  11th  level  (at  1174  feet),  but  some  ore 
has  been  mined  down  to  the-14th  level.  Be- 
low that  came  a  decided  barren  zone.  From 
the  13th  level  a  winze  was  sunk  on  the  foot- 
wall,  this  usual  practice  being  rendered  ad- 
ditionally advisable  by  the  crumbly  nature  of 
the  hanging  wall.     Just  above  the  16th  level 


a  wedge  of  white  quartz  began  to  appear,  in- 
creasing in  width  until  the  winze  was  wholly 
within  it.  This  white  quartz  was  no  good. 
On  opening  out  at  the  17th  level  (at  2332  feet) 
some  dark  quartz  containing  visible  gold  was 
cut  on  the  hanging- wall  side.  It  was  6  feet  wide 
and  rich.  Then  a  drift  was  extended  north  and 
south,  exposing  similar  dark  quartz  for  a  dis- 
tance of  337  feet,  with  14  dwt.  ore  in  the  north 
face.  The  winze  is  now  being  sunk  below  the 
18th  level  (at  2492  feet),wherea  drift  has  been 
started  northward  in  ore.  This  evidence  does 
not  indicate  a  new  mine,  as  yet,  but  most 
assuredly  it  encourages  further  exploration 
and  justifies  the  energetic  policy  of  the  man- 
agement. According  to  Mr.  Maclaren  the 
Great  Fingall  vein  is  gold-bearing  only  where 
it  crosses  a  wide  dike  of  quartz-dolerite,  which 
is  1200  feet  wide.  This  is  a  striking  proof 
of  the  relation  between  ore  deposition  and 
petrography.  Since  the  dike  dips  northwest 
the  ore-shoot  pitches  at  an  angle  made  by  the 
crossing  of  two  planes,  that  of  the  vein  and 
that  of  the  dike.  This  is  in  accord  with  ob- 
servation in  other  regions.  The  Fingall  vein 
carries  two  kinds  of  quartz,  a  dark  variety, 
which  owes  its  hue  to  "  loss  of  light  by  total 
reflection  from  internal  strain  surfaces  "  and 
a  white  quartz  of  the  ordinary  type.  The 
latter  is  younger  than  the  former  and  was  de- 
posited during  a  renewal  of  the  fracture  mark- 
ing the  line  of  the  present  lode.  More  impor- 
tant is  the  fact  that  only  the  dark  quartz  is 
rich  enough  to  constitute  profitable  ore  ;  the 
white  quartz  is  uniformly  barren.  The  re- 
appearance of  the  dark  quartz  is  therefore 
deeply  significant.  It  reminds  Mr.  Maclaren 
of  the  conditions  on  the  Champion  Reef,  in 
India,  where  the  lode,  after  passage  through  a 
poor  zone,  became  as  rich  at  4000  feet  as  it  was 
at  surface.  We  hope  the  analogy  thus  assum- 
ed may  be  fully  confirmed  by  the  logic  of  events, 
and  that  consequently  the  shareholders  may 
have  the  gratification  of  seeing  this  well-man- 
aged mine  recover  some  of  its  pristine  glory. 


JULY,    1911 


13 


Smelter  Smoke. 

In  this  issue  we  publish  a  description  of 
the  Casapalca  smelter  in  Peru;  incidentally, 
our  readers  will  find  an  illustration  showing 
how  smelter  smoke,  when  no  effort  is  made 
to  condense  and  filter  it,  will  pervade  the  sur- 
rounding atmosphere,  producing   pestilential 
conditions.     We  draw    attention  to  this  ex- 
ample of    unrestrained  smoke-production  in 
order  to  suggest   the   reasons  why  smelting 
works  in  America  and  elsewhere  have  suf- 
fered from  unpopularity  sufficient  to  facilitate 
unjust  attack  and  even  blackmailing  litiga- 
tion.    What  Casapalca  is  today,  Butte  was 
a  few  years  ago.     We  remember  when  heap- 
roasting  made  the  Silver  Bow  valley  a  verit- 
able Gehenna  and  when  a  visitor  to  Butte 
found  his  way  amid  a  noisome  murk  by  fol- 
lowing the  cough  of  the  man  preceding.    The 
utter   disregard   for   the  comfort  of  the  sur- 
rounding comm-unity,  even  the  injury  to  the 
health  of  man  and  beast,  that  marked  early 
smelting  operations  in  Western  America  was 
followed  by  an  attempt  to  outlaw  a  necessary 
part  of  the  mining  industry.     Owing  to  the 
undoubted  nuisance  created  by  the  reckless 
emission  of  arsenical  and  sulphurous  fumes 
by  one  or  two  smelters,  it  was  not  difficult 
for    farmers,    and    other    designing    persons 
posing  as  farmers,  to  use  public  opinion  as  a 
lever  for  applying  the  restrictive  decisions  of 
local  courts  against  all   roasting  operations. 
By   injunctions  and  other  legal  weapons   it 
became  possible  to  hamper  smelting  and  even 
to  put  a  stop  to  it.     Thus  the  Guggenheims 
in  1906  had  to  abandon  the  erection  of  a  cop- 
per smelter  near    San   Francisco;    thus  the 
Selby  smelter  has  been  harassed  and  the  old 
Mountain    Copper    plant,  at    Keswick    was 
forced  into  idleness.     These  are  all  in  Cali- 
fornia.    A  similar  campaign  in  Utah  resulted 
in  the  shutting-down  of  three  smelters  in  the 
Salt  Lake  valley.     The  two  copper  smelters 
in  Tennessee  were  compelled  to  mend  their 
ways  and  finally  erected  sulphuric  acid  plants 


from  which  they  now  draw  a  profit.  But 
the  biggest  legal  fight  was  that  waged  for  six 
years  between  the  Anaconda  smelter  and  the 
farmers  of  the  Deer  Lodge  valley  in  Mon- 
tana. This  finally  was  ended  in  March  by 
a  decision  of  the  Court  of  Appeals,  which 
affirmed  the  refusal  of  the  lower  court  to 
grant  an  injunction  that  would  have  entailed 
the  cessation  of  the  smelting  operations  con- 
stituting an  essential  part  of  the  mining  in- 
dustry of  the  great  copper  district  of  Butte. 
In  this  case  the  conflicting  interests  were 
well  represented,  and  the  result  appears  not 
only  to  interpret  the  law  correctly  but  also 
to  vindicate  those  fundamental  principles  of 
justice  that  are  sometimes  outraged  by  legali- 
ties. The  facts  are  as  follows :  A  smelter 
was  built  at  Anaconda  in  1884  ;  this  plant 
was  not  provided  with  proper  flues  and  dust- 
chambers,  so  that  the  smoke  did  escape 
freely  and  did  cause  injury  to  the  neighbour- 
ing ranches.  In  1895  the  old  smelter  was 
abandoned  and  operations  were  transferred 
to  a  new  and  larger  plant  in  the  same  locality, 
but  in  this  case  also  no  special  care  was  taken 
to  abate  the  nuisance  due  to  the  emission  of 
arsenical  and  sulphurous  fumes.  Appreciat- 
ing the  necessity  for  saving  the  dust,  con- 
densing the  fumes,  and  avoiding  irritation  to 
the  neighbouring  agricultural  and  pastoral  in- 
terests, the  smelting  company  remodelled  its 
plant,  built  a  high  stack,  and  made  scientific 
provision  for  preventing  the  undiluted  dis- 
tribution of  the  arsenic  and  sulphur  liberated 
from,  the  copper  ore.  Just  at  this  time,  when 
the  company  had  finally  awakened  to  its  civic 
duty,  the  farmers  in  the  valley  took  steps  to 
harass  the  smelter  people,  alleging  the  injury 
done  in  previous  years.  Thus  the  two  parties 
were  at  cross  purposes  ;  one  of  them,  awake 
to  the  public  disfavour  into  which  the  other 
had  fallen,  tried  to  levy  blackmail ;  and  the 
other,  at  the  moment  when  it  had  realized  its 
responsibility,  was  subjected  to  attack  by 
reason  of    its   earlier  sins   of   omission    and 


14 


THE    MINING    MAGAZINE 


commission .  The  Anaconda  company  caused 
an  investigation  to  be  made  and  actually  paid 
$330,000  in  settlement  of  claims.  At  the 
same  time  expense  was  incurred  freely  in 
efforts  to  determine  means  for  arresting  a 
part  of  the  noxious  gases  and  for  diluting  the 
remainder  so  that  it  also  might  be  rendered 
harmless.  This  led  to  the  construction  of 
larger  flues  and  dust-chambers,  and  the  erec- 
tion of  a  high  chimney  on  an  adjoining  hill. 
The  work  was  done  on  a  large  scale  and 
lavishly,  and  represents  a  really  earnest  and 
scientific  effort  to  meet  the  necessities  of  the 
case.  This  was  the  view  taken  by  the  Court, 
which  found  that  the  sulphur  left  in  the 
smelter  smoke  had  caused  no  damage  to  the 
complainants'  crops  since  the  remodelling  of 
the  plant  in  1903,  but  that  the  arsenic  was 
still  being  deposited  so  as  to  do  some  injury 
to  the  fodder  and  to  sicken  some  of  the  live- 
stock in  the  Deer  Lodge  valley,  and  that  so 
long  as  the  smelter  was  operated  such  dam- 
age would  continue  to  be  done.  On  the  other 
hand  no  other  process  of  smelting  was  prac- 
ticable, no  site  in  Montana  could  be  selected 
where  operations  would  be  conducted  with 
less  damage  or  inconvenience  ;  that  if  the 
smelter  were  to  close,  two-thirds  of  the  mining 
at  Butte  would  stop;  that  incomparable  in- 
jury would  be  done  to  the  farmers,  and  others, 
by  the  loss  of  a  market  for  the  products  of 
their  land  ;  and  that  the  damage  thereby  sus- 
tained would  be  greatly  in  excess  of  that  due 
to  the  smoke  from  the  smelter.  Here  justice 
wide-eyed  and  serene  must  have  smiled  good- 
naturedly.  Thus  ended  a  litigation  that  cost 
at  least  ^150,000,  that  employed  experts 
not  only  in  metallurgy  and  mineralogy,  but 
in  anatomy  and  botany,  bacteriology  and 
zoology.  The  testimony  covered  2500  type- 
written pages.  But  it  was  worth  -while  ;  for 
it  established  the  legal  principles  involved  in 
such  cases  and  furnished  a  warning  alike  to 
unreasonable  farmers  and  to  careless  smel- 
ters.    Anti-social  conduct  from  either  is  not 


tolerated  by  the  law,  which  in  such  cases  de- 
fends the  greatest  good  of  the  greatest  num- 
ber. The  organizers  of  smelters  will  be  wise 
in  refraining  from  building  furnaces  in  agri- 
cultural districts ;  the  farmer  is  warned  not 
to  attempt  to  establish  himself  where  metal- 
lurgical operations  are  necessary  to  the  exist- 
ence of  an  industrial  community. 


The  Giesecke  Mill. 

Keen  interest  has  been  aroused  by  various 
statements  emanating  from  Johannesburg  con- 
cerning the  good  work  done  by  a  new  crush- 
ing machine,  the  Giesecke  tube-mill.  It  ap- 
pears that  this  mechanical  device  has  been 
undergoing  a  test  at  the  Geldenhuis  Estate 
mill  under  the  auspices  of  the  Mines  Trials 
Committee,  a  body  of  technical  men  appointed 
bv  the  various  groups  acting  conjointly.  At- 
tention was  drawn  to  the  subject  by  Mr.  A. 
Brakhan,  who,  in  presiding  at  the  annual 
meeting  of  A.  Goerz  &  Co.,  on  May  26,  at 
Johannesburg,  said  that  a  rotary  mill,  intended 
to  replace  the  existing  stamps  and  tube-mills, 
was  undergoing  successful  trial.  Next  day, 
Mr.  Lionel  Phillips,  at  the  banquet  of  the 
South  African  Association  of  Engineers,  men- 
tioned the  matter,  saying  that  it  would  greatly 
influence  the  development  of  the  gold  mining 
industry  ;  it  would  mean  the  final  elimination 
of  amalgamating  plates  and  the  passage  of 
ore  direct  to  the  cyanide  annex  ;  it  would  dis- 
pense with  stamps  and  would  result  in  a  great 
diminution  of  capital  cost.  Since  then  a  visit 
of  inspection  has  been  made  by  many  of  the 
technical  men  resident  on  the  Rand  and  the 
general  opinion  is  that  the  Giesecke  tube-mill 
represents  an  interesting  and  suggestive  de- 
parture from  established  practice.  But  it  is 
too  early  for  positive  opinions.  The  present 
test  is  being  directed  mainly  toward  ascer- 
taining the  efficiency  of  the  machine  as  a 
composite  grinder.  It  is  a  ball-mill  with  a 
tube-mill  attachment,  or  it  can  be  described 
as  a  ball-mill  and  a  tube-mill  in  tandem.     The 


JULY,    1911 


15 


total  length  is  24  feet,  of  which  about  one 
quarter  has  a  diameter  of  7^  feet,  while  the 
remainder  is  slightly  less  than  6  feet.  The 
ore,  which  is  coarser  than  that  ordinarily  de- 
livered to  the  stamp  battery,  is  fed  by  an 
Archimedean  screw  into  the  machme,  where 
steel  balls  fall  upon  steel  liners  made  from 
plates  2  inches  thick,  12  inches  wide,  and  24 
inches  long.  These  are  bolted  at  one  end 
and  fixed  to  a  strong  spring  at  the  other.  This 
cushioning  prevents  excessive  wear  of  metal 
on  metal.  Eight  sizes  of  steel  spheres  are 
employed  ;  these  vary  from  4  inches  to  li 
inches  in  diameter,  the  biggest  being  placed 
in  the  larger  chamber,  where  the  ore  is  first 
broken  before  passing,  through  a  diaphragm, 
into  the  smaller  cylinder.  The  wear  and 
tear  is  compensated  by  adding  balls  of  the 
larger  size.  As  the  ore  enters  it  is  sprayed 
with  water  ;  this  represents  only  28*5%  by 
weight  of  the  material  pulverized,  but  it  is 
enough  to  form  an  emulsion,  which  before 
being  discharged  passes  through  a  mixer,  an 
elliptical  chamber  fitted  with  steel  arms.  The 
pulp  is  comminuted  to  a  remarkable  degree 
of  uniformity,  for  one  screen  analysis  showed 
that  86%  passed  200  mesh.  The  mill  at  the 
Geldenhuis  Estate  is  said  to  crush  360  tons 
per  day,  using  230  to  240  horse-power.  The 
total  weight  of  the  machine  is  68  tons,  of 
which  23  represents  the  steel  balls,  16i  tons 
the  liners,  and  15|  tons  the  tube  itself,  the 
remaining  weight  being  apportioned  among 
drivmg  gear  and  supports.  The  underlying 
purpose  is  to  diminish  the  proportion  of  water' 
thereby  augmenting  the  grinding  efficiency  ; 
also  it  is  intended  to  treat  the  ore  in  one  pro- 
cess, instead  of  crushing  first  in  the  stamp- 
battery  and  then  pulverizing  in  a  tube-mill. 
The  Giesecke  mill  is  said  to  receive  the  ore 
in  sizes  up  to  7-inch  cube,  but  our  Johannes- 
burg correspondent,  who  is  usually  well  in- 
formed, states  that  the  material  delivered  to 
the  machine  is  "  of  a  size  fit  for  stamp-mill- 
ing," which  we  interpret  as  meaning  that  it 


would  pass  a  2i  inch  ring.  On  its  passage 
through  the  Giesecke  tube-mill  the  ore  has 
been  reduced  to  a  pulp  80%  of  which,  at  least, 
will  pass  a  200-mesh  screen  ;  in  other  words, 
it  slimes  the  ore  in  one  operation.  At  the 
Geldenhuis  Estate  one  of  these  mills  is  tak- 
ing the  material  previously  treated  by  50 
stamps,  which,  although  of  lighter  pattern 
than  is  customary  nowadays,  would  crush 
about  300  tons  per  day.  Again,  a  plant  of  50 
stamps,  with  tube-mills  in  proportion,  would 
cost  when  erected  at  Johannesburg  about 
^20,000,  while  the  Giesecke  is  quoted  at 
^^6000,  to  which  in  both  cases  must  be  added 
the  cost  of  motive  power.  No  precise  com- 
parison can  be  made,  but  even  the  preliminary 
estimates  indicate  that  the  use  of  the  new 
machine,  if  it  does  as  reported,  would  permit 
an  enormous  reduction  in  capital  outlay.  It 
remains  to  know  the  cost  of  maintenance, 
that  is,  of  repairs  and  replacements  incidental 
to  wear  and  tear.  The  frictional  work  done 
in  grinding  350  tons  to  a  powder  cannot  be 
insignificant ;  the  abrasion  of  steel,  in  balls 
and  liners,  is  likely  to  be  a  serious  item  of 
expense.  Of  course,  in  the  ideal  tube-mill 
the  hard  lumps  of  ore  grind  the  softer  par- 
ticles, but  the  operation  assumes  that  the  har- 
der lumps  are  themselves  pulverized  within  a 
reasonable  interval.  A  minimum  use  of  water 
tends  toward  a  maximum  crushing  efficiency  ; 
this  feature  is  excellent,  but  on  the  other 
hand  the  absence  of  any  classifying  operation 
between  the  beginning  and  the  end  of  the 
composite  grinding  process  may  allow  some 
particles  of  pyrite,  encasing  the  gold,  to  pass 
with  the  pulp  without  being  re-ground.  Thus 
the  one-stage  machine  may  lack  advantages 
afforded  by  a  two-stage  process.  The  quartz, 
the  pyrite,  and  the  cement,  which  binds  the 
quartz  pebbles  of  the  banket,  represent  three 
diverse  constituents  of  the  ore,  and  yet  all 
three  undergo  exactly  the  same  process  of  re- 
duction in  the  Giesecke  mill.  Obviously  there 
are  points  on  which  fuller  technical  informa- 


16 


THE    MINING    MAGAZINE 


tion  is  requisite.  One  optimist  says  that  by 
the  use  of  this  machine  the  cost  of  treating 
ore  on  the  Rand  may  be  reduced  to  two  shil- 
lings, equal  to  half  a  pennyweight  of  gold,  per 
ton.  We  may  remind  our  readers  that  the 
operating  cost  of  mill  treatment  on  the  Rand 
averages  6  shillings  per  ton,  but  this  figure 
does  not  include  allowance  for  amortization 
of  capital  expended  in  milling  equipment. 
Here  is  the  weak  feature  of  Rand  economics. 
The  average  shareholder  overlooks  the  fact 
that  "  cost  "  at  the  last  resort  includes  re- 
demption of  capital  and  interest  upon  it  until 
redeemed.  However,  we  welcome  the  Gie- 
secke  tube-mill  as  we  welcome  any  new  de- 
vice that  may  fulfil  one  of  two  functions,  or 
even  both  of  them,  namely,  to  stimulate  me- 
chanical ingenuity  in  gold  metallurgy  on  the 
one  hand,  and  to  increase  the  profit  of  mining 
on  the  other.  The  first  conduces  eventually, 
if  not  at  once,  to  the  second. 


Prestea. 

West  African  mining  has  been  subjected 
to  so  many  disappointments,  in  part  due  to 
climatic  conditions  and  in  part  to  the  patchi- 
ness  of  the  lodes,  that  it  is  a  relief  to  read 
the  report  of  the  Prestea  Block  A  meeting. 
The  chairman,  Mr.  Edmund  Davis,  was  able 
to  give  a  most  cheerful  and  satisfactory  state- 
ment. It  is  true  more  capital  is  required,  in- 
creasing the  obligation  under  which  the  mine 
is  operated,  but  the  addition  seems  to  be  fully 
warranted  and  has  been  secured  on  terms  in- 
dicating the  good  credit  of  the  enterprise. 
The  Prestea  is  undoubtedly  one  of  the  finest 
gold  lodes  ever  uncovered  by  the  prospector ; 
it  is  a  quartz  vein  of  remarkable  uniformity 
traversing  schist ;  the  orebody  itself  has  been 
proved  for  over  7000  feet  in  length  and  will 
probably  average  8  feet  wide  of  11  dwt.  ore. 
As  far  as  it  has  been  tested  this  orebody  is  per- 
sistent and  appears  likely  to  extend  to  a  great 
depth.  On  the  No.  6  level,  at  630  feet,  which 
is  the  deepest,  an  excellent  showing  appears. 


the  drifts  north  and  south  having  been  ex- 
tended for  1000  feet  in  ore  averaging  7  feet 
in  width  and  14  dwt.  by  assay.  At  the  end 
of  1910  the  reserve  consisted  of  678,000  tons, 
averaging  43'9s.  per  ton,  and  on  May  31, 
1911,  this  had  been  increased  to  879,000  tons 
of  43'2s.  ore,  representing  ^1,490,095.  Of 
this  amount  only  ^500,000  is  likely  to  be 
available  for  dividends,  for  the  operating  cost 
is  officially  estimated  at  20s.  and  extra  ex- 
penses will  consume  fully  3s.  more.  It  is 
not  likely  that  the  total  cost  will  be  under 
25  shillings.  The  present  market  valuation 
of  the  mine,  at  30s.  per  share,  represents 
/"l, 275, 000.  Therefore  the  profit  assured  is 
not  quite  40%  on  the  present  share-value.  Mr. 
Davis  gave  ;^20,000  to  £25,000  as  a  forecast 
of  the  monthly  profit.  Taking  this  as  ;^250,000 
per  annum  actually  available  for  dividends, 
the  yield  to  those  who  buy  on  the  present 
valuation  would  be  about  20%.  At  30s.  per 
share  the  Prestea  is  a  lively  speculation,  al- 
though it  cannot  be  termed  reckless,  having 
regard  to  the  promising  showing  at  the  bottom 
of  the  mine.  At  present  60  stamps  have  been 
erected  and  40  are  at  work.  By  the  end  of 
the  year  the  full  complement  of  110  stamps  is 
expected  to  be  available,  but  shareholders  had 
better  allow  for  delays,  incidental  to  all  new 
plants,  especially  in  West  Africa. 

The  report  makes  reference  to  sanitary  ar- 
rangements and  to  the  supply  of  fresh  meat  to 
employees.  Mr.  E.  A.  Ridsdale,  a  director, 
in  his  speech  mentioned  these  matters.  They 
are  quite  as  important  as  the  assay-value  of 
the  ore.  Without  efficient  labour  and  cheer- 
ful co-operation,  the  winning  of  the  gold  is 
made  needlessly  expensive.  Directors  of  min- 
ing companies  on  the  Gold  Coast  should  rea- 
lize as  business  men,  let  alone  humanitarians, 
that  the  labourer  is  a  machine  the  efficiency 
of  which  depends  on  his  physical  well-being. 
A  notable  change  for  the  better  is  evident  of 
late  in  this  regard.  Mr.  Walter  Broadbridge, 
the  engineer  who  laid  out  the  present  scheme 


JULY,    1911 


17 


of  operations  at  the  Prestea,  and  is  respon- 
sible for  the  existing  reduction  plant,  during 
the  time  he  was  connected  with  the  company 
had  always  in  view  the  importance  of  improv- 
ing the  living  conditions  and  introduced  many 
improvements  in  sanitation  and  food-supply. 


Engineers  as  Financiers. 

In  one  of  the  earlier  issues  of  this  Magazine 
weraised  objection  to  the  suggestion  that  young 
men  about  to  become  mining  engineers  should 
start  their  career  with  the  idea  of  participating 
in  the  promotion  and  other  financial  aspects 
of  the  mining  business.     This  has  been  inter- 
preted in  some  quarters  as  a  desire  to  discour- 
age any  technical  man  from  taking  part  in  finan  - 
cial  affairs  connected  with  the  exploitation  of 
mines.   As  a  misunderstanding  appears  to  have 
arisen  and  as  the  subject  is  one  of  vital  interest 
we  shall  discuss  it  once  more,  it  being  always 
understood  that  is  not  our  function  so  much 
to  codify  practice  as  to  encourage  the  forma- 
tion of  a  healthy  public  opinion  on  this  and 
other  matters  appertaining  to  mining.   Mining 
is  a  business  based  upon  the  application  of 
science  to  labour  ;  when  thus  organized  it  be- 
comes an  industry,  whose  underlying  purpose 
is  to  make  money.     Technical  science  is  ap- 
plied to  mining  with  a  view  to  profit  ;  without 
profit  a   mine   becomes  a  mere  hole  in  the 
ground ;  therefore  an   engineer   who   cannot 
direct  operations  so  that  they  yield  dividends 
is  a  failure.     The  engineer  must  keep  an  eye 
on  the  pounds,  shillings,  and  pence  ;  if  he  does 
not,  he  is  an  idle  dreamer  or  an  impracticable 
theorist.     Hence  the  successful  mining  engi- 
neer must  be  a  keen  business  man,  combining 
a  knowledge  of  technology  with  an  apprecia- 
tion of  finance ;  but  this  does  not  mean  that 
he  must  be  a  financier.    Here  we  begin  to  part 
company  with  some  of  our  friends.     To  ex- 
press  that    divergence,   we    shall    employ    a 
homely  simile  :    A  father  does  not  advise  a 
mere  boy  to  drink  whisky  and  soda  ;  he  is  per- 
fectly aware  that  in  the  course  of  time  the  boy 


will  become  a  young  man  and  will  acquire  the 
habit,  by  no  means  injurious  when  followed 
temperately.  If  a  youngster  takes  to  the  stimu- 
lant when  unnecessary  it  is  apt  to  lead  to  ex- 
cesses ;  acquired  too  soon,  the  habit  will  ruin 
his  stomach.     Thus  it  is  with  financial  partici- 
pation   on    the  part  of   the   young  engineer. 
As  he  gains  in  experience  and  becomes  con- 
cerned with  large  mining   enterprises,  he  is 
bound    to    take    as    keen    an   interest   in   the 
machinery  of  finance  as  in  that  of  the  mill  or 
smelter  ;  inevitably  also,  especially  if  his  mind 
has  a  bent  that  way,  he  will  participate,  and 
in  some  cases  direct  the  monetary  operations. 
But  should  he   do   this  prematurely   he  will 
develop  tendencies  checking  his  natural  de- 
velopment as  a  technologist.     The  apprentice 
who  is  learning  his  profession  is  corrupted  by 
participating  in  promotions  and  the  like  at  the 
time  when  he  should  be  giving  his  undivided 
energies  to  the    fulfilment  of  his  duty  as  a 
technical  man  ;  until  he  has  won  his  spurs  and 
gained  discretion  it  is  well  for  him  to  keep  his 
eye  on  the  ball,  neither  slicing  a  commission 
nor  pulling  a  promotion.     The  average  young- 
ster that  dabbles  in  stocks  and  shares,  in  com- 
missions and  promotions,  in  early  life  is  un- 
likely ever  to  learn  engineering  thoroughly  ; 
if,  on  the  other  hand,  he  postpones  taking  a 
hand  in  the  most  tricky  and  most  difficult  part 
of  the  business  until  he  has  gained  some  of  the 
experience  of  living  and  learning,  he  may  hope 
to  play  his  part  usefully  to  himself  and  others. 
Again,  we  hold  that  it  is  not  well  for  a  man  to 
take  the  role  of  a  financier  when  he  is  with- 
outadequate  responsibility ;  we  deprecate  such 
financing  on  the  edge  of  a  razor  as  gives  no 
hostage  for  good  conduct.     The  schemer  who 
risks  other  people's  money   in  order  that  he 
may  make  a  big  gain  is  not  a  financier  ;  he  is 
an  irresponsible  adventurer.     Such  men  play 
a  lone  hand  and  are  dangerous  to  the  commu- 
nity.    Therefore  financial  participation  on  the 
part  of  an  engineer  is  only  commendable  when 
he  gives  bonds,  as  it  were,  that  is,  has  money 


18 


THE    MINING    MAGAZINE 


enough  of  his  own  to  make  him  properly 
cautious.  This  apphes  to  older  as  well  as 
younger  men,  but  as  the  acquisition  of  capital 
is  a  matter  of  time  it  applies  more  directly  to 
the  younger.  We  speak  of  the  average  man. 
It  so  happens  that  some  young  engineers  of 
quite  exceptional  business  capacity  have  de- 
veloped as  successful  financiers  at  an  early 
age  and  it  has  been  assumed  that  what  they 
have  done,  others  can  do.  This  we  disbelieve. 
Others  have  tried  to  do  it  and  have  suffered 
shipwreck.  We  speak  with  a  wide  acquain- 
tance with  our  profession  and  do  not  hesitate 
to  say  that  the  premature  development  of  a 
taste  for  financial  speculation  has  ruined  more 
young  engineers  than  wine,  women,  and  song. 
We  take  life  as  we  see  it.  Theoretically  a 
man  ought  to  be  able  to  dabble  in  the  waters 
of  the  Stock  Exchange  without  drowning  ; 
academically,  he  ought  to  hold  a  financial  in- 
terest without  vitiating  his  judgment ;  practi- 
cally, he  rarely  does  either  one  or  the  other. 


Platinum  &  Gold  Concessions. 

A  few  days  after  our  June  issue  went  to 
press  the  prospectus  was  issuedof  the  Platinum 
&  Gold  Concessions  of  Colombia.  This  is  an 
example  of  ill  regulated  energy  as  applied  to 
mining.  The  company  is  formed  to  exploit 
placers  in  the  department  of  Cauca,  Colombia. 
As  evidence  of  probable  success  the  opinion 
is  given  of  a  native  gentleman  who  is  Inten- 
dant  of  Choco,  and  this  is  followed  by  extracts 
from  sundry  writings  of  an  wholly  inconclusive 
character.  No  real  report  by  an  engineer  is 
vouchsafed,  although  one  of  the  directors  is  an 
Associate  of  the  Institution  of  Mining  and 
Metallurgy.  He,  at  least,  ought  to  know — if 
his  fellow  directors  do  not — that  the  technical 
data  are  worthless  as  evidence  of  a  profitable 
enterprise.  The  only  simulacrum  of  a  report 
states  that  the  writer  of  it  "  cannot  tell  the 
number  of  tons  of  mineral  therein  [referring 
to  the  concessions]  contained,  because  this 
would  be  a  question  of  calculation."      From 


which  it  might  be  inferred,  erroneously,  that 
the  data  for  an  estimate  exist,  but  that  the 
gentleman's  early  teaching  in  arithmetic  was 
faulty.  The  putative  shareholder  is  told  con- 
cerning the  concession  that  "  its  richness  is 
well  known  and  acknowledged  in  various  pub- 
lications written  by  eminent  men."  This  is 
hardly  good  enough  even  for  a  financial  gam- 
bol !  Much  the  same  might  be  said  of  the 
gravel  of  the  river  Colchis,  of  the  Ethiopean 
hinterland,  of  Greensland's  icy  m.ountains  and 
India's  coral  strand.  Indeed  the  proof  of 
economic  value  is  too  absurd.  This  is  not 
business,  but  farce.  After  the  Intendant  of 
Choco  comes  a  quotation  from  the  writings  of 
the  late  R.  B.  White,  known  to  us  as  a  fair 
geologist  and  railroad  engineer,  but  constitu- 
tionally too  optimistic  to  be  regarded  as  a 
trustworthy  appraiser  of  mines.  For  instance, 
m  1886  he  made  a  glowing  report  on  the  La 
Plata  mine  in  Tolima  and  it  required  John 
C.  F.  Randolph's  good  sense  to  correct  a 
wholly  erroneous  estimate  of  a  mine  that 
never  passed  beyond  the  prospecting  stage 
and  was  long  ago  abandoned  as  worthless.  Of 
course,  it  is  well  known  that  gold  and  platinum 
are  to  be  found  in  the  gravel  of  the  Choco  and 
they  have  been  extracted  in  a  desultory  way  for 
centuries  by  nomadic  mazamorreros  or  gold 
washers,  with  cacho,  zambullidora,  or  the  or- 
dinary hatea,  as  a  means  of  concentration  by 
hand.  But  the  region  has  not  been  either 
tested  or  explored  by  the  modern  methods  of 
boring  and  shaft-sinking  ;  in  short,  it  remains 
to  be  proved  whether  the  deposits  can  be  ex- 
ploited profitably  on  a  large  scale.  On  this 
point  the  prospectus  says  nothing,  although 
the  Intendant's  estimate  of  15  grammes  of 
platinum  and  gold  per  ton  is  employed  as  a 
basis  for  the  calculation  that  with  a  daily  out- 
put of  150  tons  the  profit  would  be  £'M,QOQ 
per  annum.  Plainly,  the  scanty  evidence 
might  warrant  systematic  prospecting  but  it 
does  not  justify  an  appeal  to  the  public  in  the 
manner  of  the  prospectus. 


SPECIAL    CORRESPONDENCE 


News   from  our  own  Correspondents  at  the  principal  mining  centres 


TAQUAH. 
Railway  Vagaries. — Mine- Managers  in 
West  xA.frica  are  frequently  wroth  at  the  pe- 
culiar manner  in  which  railway  matters  are 
conducted,  and  the  experience  of  the  manager 
of  Quaw  Badoo  forms  a  good  example.  He 
wished  to  rail  a  second-hand  locomotive-type 
boiler  from  Prestea  to  a  point  about  100 
yards  from  the  Ankobra  bridge,  a  total  dis- 
tance of  probably  li  miles.  The  weight  was 
stated  at  10  tons,  but  there  is  no  Government 
weigh-bridge  at  Prestea  and  the  Traffic  In- 


construction  ;  a  little  more  common  sense  in 
administration  would  make  such  a  saving 
that  freights  could  easily  be  reduced. 

Prestea. — Another  piece  of  bad  luck  must 
be  added  to  the  many  that  have  befallen  this 
unfortunate  mine.  The  boiler  plant  was  in  a 
forward  state,  and  the  iron  chimney,  a  struc- 
ture about  140  ft.  high  by  8  ft.  diameter,  and 
about  30  tons  weight,  was  being  lifted  into 
place  when  a  derrick  canted,  throwing  the 
whole  weight  on  to  one  block,  which  gave 
way,  so  that  the  chimney  fell  right  across  the 


OBUASI,   HEADQUARTERS   OF   THE  ASHA.\TI  GOLDFIELDS. 


spector  (a  white  man)  said  the  truck  contain- 
ing the  boiler  would  have  to  be  sent  to 
Taquah  to  be  weighed.  Rather  than  have 
any  delay  the  mine-manager  offered  to  pay 
for  16  tons,  the  maximum  truck-load,  but 
'red  tape'  ordered  the  lot  off  to  Taquah  (a 
distance  of  about  20  miles  each  way)  where 
the  nett  weight  was  found  to  be  9  tons  16  cwt. 
The  Railway  Department  had  all  that  extra 
haulage  for  nothing  and  lost  the  freight  on  5 
tons  4  cwt.,  and  the  mine-manager  lost  nearly 
a  week's  work.  The  railway  is  paying  hand- 
some returns  on  a  most  extravagant  rate  of 


boiler-house,  and  the  whole  of  the  middle 
section  collapsed  as  if  made  of  paper.  The 
roof  of  the  boiler-house  was  badly  crushed, 
but  being  a  steel  building  it  fortunately  pre- 
vented the  chimney  from  falling  on  the  boilers 
beneath.  The  repair  of  the  chimney  will  cost 
hundreds  of  pounds,  besides  delaying  the  com- 
pletion of  the  boiler- plant. 

Forty  stamps  are  at  work  intermittently, 
and  the  first  three  bars  of  bullion  from  the 
new  plant  were  brought  into  Tacjuah  this 
week.  You  will  probably  hear  of  the  value 
before  we  do.     There  are  50  stamps  erected 


19 


20 


THE    MINING    MAGAZINE 


and  we  hear  that  the  duty  for  the  actual 
working  time  amounts  to  11  tons  per  stamp 
per  day.  It  is  proposed  to  erect  another  50 
stamps,  but  this  addition  may  be  postponed 
as  the  present  mill  can  deal  with  as  much 
ore  as  can  be  handled.  Owing  to  the  failure 
of  the  main  supply-pump  at  the  Ankobra 
river,  the  water  from  the  mine  has  been  used 
for  milling  purposes. 

Rainfall. — The  May  rainfall  was  unusu- 
ally heavy,  and  in  consequence  most  mines 
have  had  to  contend  with  an  additional  influx 
of  water,  and  those  depending  on  wood  fuel 
will  be  put  to  much  inconvenience.  The 
greatest  trouble  will  be  caused  in  outside  dis- 
tricts among  prospecting  propositions.  June, 
which  is  usually  the  wettest  month  of  the 
year,  is  behaving  nicely  so  far,  the  rainfall 
for  the  first  8  days  being  very  light. 

Timber  Foundations.  —  The  Abbontia- 
koon  new  stamp-mill   is   supposed  to  be  on 
order,  and  it  is  to  be  hoped  that  the  engineers 
have  given  some  thought  to  the  material   to 
be  used  in  the  foundations.     These  in  most 
mills    in   West   Africa  are   usually  made   of 
concrete  as  a  base,  but  in  the  Wassau  mill 
the    mortar- blocks    were    of    imported    pitch 
pine,  whichspeedily  rotted, givingmuch  trouble 
on   the    last    two    years  running.      In    other 
cases,  such  as  the  50-stamp  mill  of  the  Tacjuah 
mine,    the    main    base    was    of  concrete,   on 
which  were  laid  cast-iron  anvil-blocks  to  re- 
ceive the  mortar-boxes  ;  the  longitudinal  sills, 
strake  sills,  and  the  mill-posts  and  ore  bins 
were  of  wood.     The  mill  started  in  July  1907, 
but  the  ravages  of  this  climate  are  so  severe 
that    the  timbers  are  rapidly  decaying,   and 
indeed  are  now  being  replaced  in  connection 
with  30  stamps.     The  present  manager,  wise 
in  his  generation,   is  preparing  to  use  steel 
girders  and  reinforced  concrete   in  place   of 
timber,  so  that  when  the   full  50  stamps  re- 
sume   crushing    there    should  be   no   further 
trouble  about  foundations  during  the  life  of 
the  mill.     Pine  timbers  last  fairly  well  in  this 
climate,  if  they  can  be  kept  either  quite  dry 
or  else  completely  under  water,  but  as  neither 
of  these  conditions  can  be  fulfilled  in  a  stamp- 
mill  foundation,  other  material   must  be  util- 
ized   in    construction    work.      Even   battery- 
posts  fail  quickly  if  made  of  wood,  while  the 
dampness  in  the  ore  is  generally  sufficient  to 
ensure  speedy  destruction  of  a  wooden  bin. 
Local  timber  would  be  more  enduring  ;   Kaku, 
Kwisaba,  and  Odum  furnish  excellent  wood, 
and    might   give   much   better   results  if  the 
trees  were  '  rung '  a  year  or  so  before  felling, 
so  that  the  timber  could  season  in  an  erect 


position  as  it  stands ;  but  there  is  no  doubt 
that  steel  and  reinforced  concrete  will  in  the 
end  prove  most  economical.  It  is  found  in 
ore-bins,  for  example,  that  pitch  pine  of  12 
by  12  in.  section  usually  rots  completely  in 
about  4  years.  But  is  there  any  reason  why 
the  ore-bins  both  at  the  'bank'  and  in  the 
mill  cannot  be  constructed  completely  of  steel  ? 
On  all  the  principal  mines  the  practice,  until 
recently,  has  been  to  timber  the  shafts  with 
8  by  8  in.  pitch  pine,  a  custom  which  is  still 
followed  in  some  places,  but  steel  setts  are 
now  being  generally  used  with  great  advan- 
tage. 

TORONTO. 

The  Bureau  of  Mines  has  issued  a  state- 
ment of  the  output  of  the  metalliferous  mines 
and  works  of  Ontario  during  the  first  three 
months  of  the  year,  the  total  value  being 
$6,808,769.  The  outputof  silver  was  7,530,487 
oz.  valued  at  $3,708,544,  as  against  6,329,927 
oz.  of  the  value  of  $3,041,156  for  the  corres- 
ponding period  of  last  year.  The  production 
of  pig  iron  was  115, 454,  valued  at  $1,823,717  ; 
an  increase  of  $73,321.  Copper  and  nickel 
show  decreases,  the  output  of  the  former  being 
2131  tons,  valued  at  $303,240 — a  diminution 
of  $53,834 — while  the  production  of  nickel, 
4124  tons,  was  valued  at  $884,292,  being  a 
decline  of  $246,032.  Porcupine  does  not  figure 
prominently  as  yet  in  the  returns,  the  total 
output  of  gold  being  only  1813  oz.  valued  at 
$33,990. 

Porcupine. — The  laying  of  the  rails  on 
the  Porcupine  branch  of  the  Temiskaming  & 
Northern  Ontario  Railway  has  been  com- 
pleted, and  it  is  announced  that  the  line  will 
be  regularly  in  operation  by  the  beginning  of 
July.  An  arrangement  has  been  effected  under 
which  the  road  will  be  extended  about  five 
miles  farther  west,  so  as  to  serve  the  Hollinger 
and  other  mines  in  that  part  of  the  district. 
TheTimmins-McMartin  syndicate  has  agreed 
to  finance  the  extension  by  advancing  about 
$150,000  to  the  railway  commission.  De- 
velopment work  at  the  Hollinger  has  been 
delayed  by  the  bush  fire  on  May  20,  which 
destroyed  nearly  all  the  buildings  and  most  of 
the  plant, causingadirectlossof  about  $125,000. 
The  plant  will  be  renewed  as  soon  as  possible 
on  a  larger  scale,  with  60  stamps  in  place  of 
30,  as  at  first  proposed,  and  cyanide  equip- 
ment. It  will  be  difficult  to  get  in  the  ma- 
chinery on  account  of  the  condition  of  the 
roads,  and  the  mill  is  not  likely  to  be  ready 
to  start  before  August.  So  much  ore  is  on 
hand  that  the  company  will  not  be  able  to  do 


JULY,    1911 


21 


custom  work,  as  at  first  proposed.  Power 
from  the  plant  at  Sandy  Falls  on  the  Matta- 
gami  river  is  in  readiness  as  soon  as  connec- 
tions can  be  made.  The  workings  are  200  ft. 
deep ;  at  this  level  200  ft.  of  drift  has  been 
made  on  the  main  vein,  which  is  from  4  to  20 
ft.  wide.  The  assays  vary  greatly,  but  the 
high  values  found  at  the  100-ft.  level  have  in 
some  instances  been  duplicated.  Owing  to 
favourable  reports  the  HoUinger  continues 
to  lead  the  stock  market,  and  has  been  latterly 
advanced  in  price,  being  quoted  at  over  $15. 
The  other  Porcupine  issues  have  also  gener- 
ally appreciated.  Little  interest  is  taken  in 
the  Cobalt  stocks. 


been  found  to  unite  at  the  depth  of  40  ft. 
forming  a  4-ft.  vein  showing  free  gold.  The 
Scottish  Ontario  has  struck  free  gold  in  a 
shaft  18  ft.  deep.  The  No.  1  shaft  is  down 
100  ft.  and  about  500  ft.  of  driving  and  cross- 
cutting  has  been  done.  The  Rea  vein  has 
been  struck  at  the  depth  of  200  ft.  by  a  cross- 
cut 14  ft.  from  the  shaft.  It  is  richer  than  on 
the  surface  and  23  in.  wide.  The  Jupiter 
lode  has  been  traced  by  stripping  for  350  ft. 
on  the  adjoining  Booth-Armstrong  property, 
where  it  has  been  cut  at  83  ft.  with  a  diamond- 
drill.  The  Success  property,  comprising  four 
claims  in  the  township  of  Tisdale,  has  been 
sold  to  W.  Laing  Malcolmson,   of    London, 


A   PORTAGE   ON    THE    WAY   TO  PORCUPINE. 


The  Vipond  on  the  100-ft.  level  has  cut  a 
long  high-grade  ore-shoot,  which  has  been 
stripped  on  the  surface  for  several  hundred 
feet.  The  main  shaft  on  the  Dome  Extension 
has  been  sunk  nearly  to  the  100-ft.  level.  As 
soon  as  this  is  reached  a  cross-cut  will  be  run 
to  tap  the  main  vein,  which  is  about  30  ft. 
from  the  shaft.  It  is  36  ft.  wide  with  four 
lateral  veins  carrying  high-grade  ore  on  the 
surface.  Pearl  Lake,  which  sustained  a  loss 
of  about  $15,000  by  the  fire  last  month,  is 
pushing  development  work  and  has  recently 
made  some  good  finds.  Two  shafts  are  down 
about  60  ft.  near  the  two  principal  orebodies 
with  encouraging  results.  At  the  Preston 
East  Dome  a  number  of  quartz  stringers  have 


after  undergoing  a  careful  examination  by  H. 
Brian  Pearson,  an  P^nglish  engineer.  Ralph 
A.  Meyer  has  been  appointed  manager  and  a 
force  of  50  men  will  be  engaged.  David 
Richards,  who  has  been  in  Canada  since  Feb- 
ruary representing  tlie  Bewick-Moreing  in- 
terests, has  sailed  for  luighuid.  The  Swastika 
has  increased  its  capital  from  $1,000,000  to 
$2,000,000  in  order  to  buy  additional  claims 
and  erect  a  new  mill. 

Cobalt  shipments  have  latterly  been  well 
maintained,  but,  owing  to  the  increased  out- 
put of  bullion  and  concentrate,  the  tonnage  of 
ore  shows  a  decrease  as  compared  with  last 
year.  The  Ni pissing  intends  to  sink  a  shaft 
on  vein  No.  64,  which  has  been  very  produc- 


22 


THE    MINING    MAGAZINE 


tive,  to  a  depth  of  1000  ft.  in  order  to  test 
conditions  at  that  level.  The  Nova  Scotia, 
which  has  a  cyanide  plant  in  Cobalt,  has 
arranged  to  treat  ore  from  the  Kerr  Lake  and 
Crown  Reserve  mines,  and  to  enable  the  mill 
to  treat  200  tons  daily  its  capacity  will  be 
nearly  doubled  at  a  cost  of  $100,000.  The 
ore  will  be  conveyed  to  the  mill  by  an  aerial 
tramway  5000  ft.  long.  The  Rochester  will 
sink  to  the  400-ft.  level  and  work  the  continu- 
ation of  the  Lumsden  vein  into  the  property 
at  the  300-ft.  level  from  the  Lumsden  mine. 
The  Waldman,  in  the  Gillies  Limit,  which 
has  been  closed  down  for  some  time,  is  re- 
suming operations.  Trenching  on  the  surface 
is  being  undertaken  in  the  hope  of  striking 
other  veins.  The  Beaver  has  declared  an 
interim  dividend  of  3%.  The  Temiskaming 
will  pay  its  regular  quarterly  dividend  of  3%. 
The  Crown  Reserve  has  declared  2%,  with 
3%  extra.  The  power-plant  of  the  Nancy 
Helen  has  been  destroyed  by  fire,  entailing  a 
loss  of  $16,000.  The  mine  has  been  closed 
for  some  time.  The  Kerry  mine  has  resumed 
operations  with  a  large  force  on  the  350-ft. 
level.  The  La  Rose  is  opening  a  third  level 
from  the  main  shaft  at  270  ft.,  the  deepest 
point  reached. 

The  Lake  of  the  Woods  district  is  again 
attracting  attention  from  capitalists  and  pros- 
pectors. Several  old  mines  have  recently 
been  re-opened.  The  Ontario  Government 
has  commissioned  A.  L.  Parsons,  lecturer  in 
mineralogy  in  Toronto  University,  to  make 
an  examination  of  the  district,  which  was 
prominent  in  1897.  The  Mikado  mine  has 
been  re-opened  with  R.  B.  Nickerson  as  super- 
intendent. 

Yukon. — The  Canadian  Government  has 
issued  an  order  in  council  abolishing  the  royal- 
ty on  gold  extracted  from  quartz  in  the  Yukon 
territory,  as  a  means  of  encouraging  this  in- 
dustry. So  far  the  results  of  quartz  mining 
in  the  Yukon  have  been  unsatisfactory  and  no 
royalty  has  been  collected. 

Diamonds.  —  The  recent  discoveries  of 
diamonds  in  British  Columbia  have  been  fol- 
lowed by  another  find  of  the  same  character 
by  R.  A.  A,  Johnston,  mineralogist  to  the 
Canadian  Geological  Survey,  in  the  old  chro- 
mite  mines  at  Black  Lake,  in  Quebec.  Officials 
of  the  Survey  are  endeavouring  to  discover  a 
commercially  feasible  process  for  extracting 
the  diamonds  from  the  chromite.  With  this 
object  in  view  Mr.  Johnston  will  sail  shortly 
for  Germany,  taking  with  him  samples  of  the 
Canadian  diamonds.  The  largest  of  these  is 
three-sixteenths  of  an  inch  in  diameter. 


DENVER. 
Colorado. — Mining  men  have  long  held  it 
as  one  of  their  articles  of  faith  that  a  great 
camp  should  be  discovered  within  the  State 
every   ten    years.     Since    the    second  decade 
has  now  passed,  however,  without  a  discovery 
comparable  to  those  of  Gilpin,  the  San  Juan, 
Leadville,  or  Cripple  Creek,  many  prophets 
have  become  discouraged,  though   none   ap- 
parently have  lost  faith  in  the  final  outcome. 
Mining  men  are  puzzled  and  half  indignant 
at  the  failure  of  any  great  new  camp  to  come 
forward  since  Cripple   Creek    electrified    the 
world.       Two    years    ago,   in    writing   of  the 
situation,  I  spoke  of  them  as  waiting  Micawber- 
like  for  something  to  '  turn  up.'     Now  they 
have  adopted  instead  the  crowbar  philosophy 
and   propose    to    turn    something    up.       The 
whole  State  is  discussing  means  to  promote 
the  discovery  of  a  new  mining  district.     Nu- 
merous committees  have  been  formed,  and  a 
persistent   effort   is   being  made    to  advertise 
the  mineral  resources  of  the  State.     That  new 
mines  have  not   been  opened  as   rapidly   as 
have  new   farming  districts  is  clear,  and    it 
needs    but    a    casual    study   of    the   smelting 
situation  to  convince  one  that  mining  in  Col- 
orado has  not  kept  pace  with  general  develop- 
ment in  and  outside  the  State.     A  variety  of 
reasons  have  been  urged,  but  it  is  becoming 
recognized  that  it  will  not  suffice  to  continue 
to  sell  holes  in  the  ground  to  Eastern  tourists 
or  simpletons.      Mines,   not    nicely-engraved 
stock  certificates,  are  needed  ;  to  find  mines, 
prospecting    is  essential.      The   hills  are  no 
longer  covered  with  prospectors,  and  it  is  no 
longer  true  that  every  merchant  and  profes- 
sional man  is  contributing  to   a  grub-stake. 
Many  reasons  may  be  cited  :  the  discovery  of 
new  veins  now  requires  more  skill,  time,  and 
money  than  when  rich  ore-shoots  were  still  to 
be  found  at  the  surface  ;   more  avenues  exist 
for  profitable  employment  of  both  skill  and 
money   than   when   mining   was  the  only  in- 
dustry.    The  fact  remains,  however,  that  there 
are  large  areas  in  Colorado,  geologically  favour- 
able to  the  occurrence  of  minerals,  and  these 
have  been  but  inadequately  investigated.    One 
of  the  Denver  newspapers  is  advertising  itself 
and  attracting  attention  to  the  State  by  col- 
lecting a  '  grub-stake  fund  '  to  be  administered 
by  a  committee  consisting  of  Max  Boehmer, 
James  Doyle,  and   Ernest  Le  Neve   Foster. 
It  is  proposed  to  send  out  experienced  pros- 
pectors,  including  in  each  party  a  school-of- 
mines   man   and   an   old    prospector.      These 
are   to  locate   claims  on   anything   of    value. 
At   intervals   the   various   parties    are   to    be 


JULY,    1911 


23 


IN    THE  HEART  OF   COLORADO. 


1—3 


24 


THE    MINING    MAGAZINE 


visited  by  a  mining  engineer,  who  will  advise 
the  men  regarding  their  work,  and,  if  the 
money  is  not  honestly  and  intelligently  ap- 
plied, the  supply  of  funds  will  be  stopped. 
A  number  of  the  best  known  assayers  are 
co-operating  with  the  committee  by  making 
free  tests,  and  there  would  seem  to  be  some 
hope  of  success.  Another  feature  of  the 
moment  is  that  support  will  be  furnished  to 
any  prospector  who  is  hampered,  or  thinks 
himself  hampered,  by  officers  of  the  Forest 
Service.  There  has  been  friction  between 
prospectors  and  forest-rangers  and  the  matter 
has  been  magnified  until  opponents  of  the 
Service  lay  at  its  door  blame  for  the  whole 
failure  to  discover  a  new  district.  This  is 
unjust,  but  the  assurance  that  any  real  inter- 
ference with  prospecting  will  be  promptly 
investigated  and  adjusted,  will  have  a  good 
psychological  effect.  Whether  the  new  move 
will  result  in  the  discovery  of  competent 
prospectors,  which  is  pre-requisite  to  finding 
ore,  is  not  certain.  So  much  has  been  said 
of  chance  discovery  and  so  many  of  the  larger 
mines  have  been  found  by  inexperienced  men, 
that  there  is  no  general  recognition  of  the 
fact  that  really  careful  investigation  of  any 
area  requires  skill  and  patience.  Competent 
and  determined  men  have  generally  been  able 
to  get  a  grub-stake.  The  best  hope  is  that 
the  new  movement  may  attract  recruits  of  the 
right  temperament  who  may  develop  real  skill. 
That  there  are  great  mines  yet  to  be  found  in 
Colorado  no  one  familiar  with  the  State  can 
doubt. 

State  Aid. — It  is  perhaps  characteristic 
of  the  growing  American  tendency  to  depend 
on  organized  social  effort  in  place  of  the 
sturdy  individualism  that  characterized  the 
work  of  the  isolated  pioneers  that  Colorado 
is  now  making  mcreasingly  liberal  appropria- 
tions for  the  investigation  of  her  mineral  re- 
sources. Large  sums  have  been  given  to  the 
Agricultural  Schools,  and  it  has  long  been 
customary  here  as  in  other  States,  to  support 
agricultural  experiment-stations.  Relatively 
little  has  been  given  to  the  excellent  School 
of  Mines  at  Golden,  and  nothing  has  been 
spent,  till  recently,  upon  experimental  work 
in  connection  with  mining.  In  the  last  ten 
years  the  Agricultural  College  has  received 
11,705,858  and  the  School  of  Mines  $782,174. 
Fortunately  the  tendency  now  is  toward  more 
liberal  support  for  the  mining  school  and  also 
for  supplemental  investigations.  New  build- 
ings have  been  erected  and  larger  appropria- 
tions made  for  teaching  and  laboratory  work. 
One  of  the  most  interesting  departures  has 


been  the  erection  of  a  large  ore-testing  plant 
at  Golden,  at  which  engineers  may  carry  on 
tests  to  determine  methods  of  treatment  for 
any  ore.  The  professors  will  be  available 
for  consultation,  and  the  students,  while  serv- 
ing as  assistants,  will  get  valuable  training 
under  rigorous  commercial  conditions.  A  sup- 
plemental appropriation  of  $50,000  has  just 
been  made  to  equip  this  laboratory.  Unfor- 
tunately, politics  has  always  entered  even 
into  the  educational  work  of  Colorado,  and 
now  an  effort  is  being  made,  at  the  behest  of 
one  of  the  powerful  politicians  of  the  State, 
to  force  the  resignation  of  Victor  C.  Alderson, 
the  president  of  the  School  of  Mines.  Mr. 
Alderson  came  to  Colorado  in  1903  from  the 
Armour  Institute  of  Technology.  He  is  a 
mathematician,  a  graduate  of  Harvard,  and 
has  done  excellent  service.  These  recurrent 
squabbles  have  done  much  to  hamper  work 
at  Golden  ;  it  is  to  be  hoped  that  a  sound 
public  opinion  may  soon  develop  and  prevent 
interference  with  any  of  Colorado's  schools. 

Another  agency  of  the  State  for  developing 
its  mineral  resources  is  the  Geological  Survey, 
now  in  charge  of  R.  D.  George,  of  the  State 
University.  In  the  short  time  since  the  de- 
partment was  organized,  Mr.  George  has  done 
excellent  work,  particularly  in  the  study  of 
the  tungsten  industry  in  Boulder  county  and 
the  rejuvenation  of  mining  at  Montezuma. 
It  is  pleasant  to  record  that  the  value  of  this 
work  has  just  been  recognized  by  a  liberal 
increase  in  appropriations.  It  is  not  so  pleas- 
ant that  at  the  same  time  Mr.  George  is  in 
the  hospital  as  a  result  of  over-work.  I  am 
glad  to  say  that  no  doubt  of  his  recovery  is 
entertained.  Unquestionably,  he  will  make 
excellent  use  of  the  money  when  he  is  again 
able  to  take  the  field,  for  Colorado  is  a  mining 
region  that  presents  an  extraordinary  diversity 
of  lode-structure  and  geological  conditions. 

Legislation  relating  to  mining  attracted 
much  attention  at  Denver  this  winter  and 
now  that  the  Legislature  has  adjourned  it  is 
possible  to  take  account  of  results.  The  pro- 
posed changes  in  mine  inspection  were  not 
made,  the  bill,  after  numerous  amendments, 
having  finally  failed  to  become  a  law.  It 
will  be  recalled  that  following  the  disastrous 
explosions  last  fall  in  the  coal  mines,  condi- 
tions were  investigated  by  a  commission  ap- 
pointed by  the  Governor  and  a  new  act  pro- 
posed, designed  to  greatly  increase  safety  in 
mines.  The  cost  of  the  new  inspection  was 
to  be  met  by  a  tonnage  tax  and  in  other  par- 
ticulars the  plan  was  so  radical  as  to  fail  of 
the  necessary  popular  support.     It  was,  how- 


JULY,    1911 


25 


ever,  defeated  by  the  devious  and  familiar 
method  of  first  loading  it  with  distasteful 
amendments.  Colorado  has  thus  postponed 
takmg  a  step  that  is  inevitable,  although  the 
discussion  has  greatly  enlightened  the  public. 
Some  changes  were  made  in  taxation  laws 
and  a  means  has  been  provided  for  forming 
mine-drainage  districts.  Whereas  it  has  long 
been  possible  in  America  for  farmers  to  or- 
ganize to  drain  their  lands  and  to  compel  any 
recalcitrant  to  pay  his  due  portion  of  the  cost, 
there  has  been  no  similar  rule  regarding  mines. 
The  great  Roosevelt  adit  at  Cripple  Creek 
was  driven  by  a  company  organized  as  a  re- 
sult of  private  effort  and  there  was  no  way  to 
compel  any  one  however  much  benefited,  to 
contribute  to  the  cost.  Now  that  $50,000  is 
needed  to  extend  the  work  it  is  still  necessary 
to  solicit  funds  as  for  a  public  charity.  The 
new  law  will  remedy  this  condition. 

Tunnel  engineers  are  much  interested  in 
a  bill  passed  by  the  Legislature  submitting 
to  the  people  a  proposal  to  issue  bonds  to  the 
value  of  $4,000,000  to  furnish  funds  for  dri- 
ving a  tunnel  through  the  main  range  of  the 
Rocky  Mountains  at  Rollinsville.  This  tun- 
nel was  originally  projected  in  connection 
with  the  Denver,  Northwestern  &  Pacific 
railroad,  familiarly  known  as  the  '  Moffat  line  ' 
and  designed  to  furnish  a  short  cut  directly 
west  from  Denver.  The  railroad  company 
found  itself  unable  to  complete  the  project 
and  it  is  now  proposed  to  make  the  bore  as  a 
public  enterprise,  reserving  right  of  way  to 
any  railroad  having  or  making  the  necessary 
connections.  Two  surveys  call  respectively 
for  four  and  six  miles  of  tunnel.  The  im- 
pression is  that  the  people  will  vote  for  the 
bonds  and  that  the  work  will  be  undertaken. 
In  the  meantime  the  Laramie- Poudre  tunnel, 
undertaken  in  connection  with  an  irrigation 
project,  is  nearly  completed.  In  May  635  ft. 
of  driving  was  accomplished  and  up  to  May 
25  progress  was  at  a  rate  of  700  ft.  per 
month.  Broken  ground  was,  however,  then 
encountered  and  slower  progress  cut  down 
the  total.  D.  W.  Prunton,  consulting  en- 
gineer, hopes  still  to  establish  the  700  ft. 
record  before  completing  the  work.  He  al- 
ready has  the  American  record  for  hard-rock 
work.  An  interesting  and  valuable  paper  on 
tunnel-driving  methods  was  read  by  W.  L. 
Saunders  at  the  Wilkes  -  Barre  meeting  of 
the  American  Institute  of  Mining  Engineers 
early  in  June.  It  attracted  much  attention 
in  Colorado,  where  many  deep  drainage  adits 
have  been  driven  in  connection  with  min- 
ing. 


JOHANNESBURG. 
Kimberley   Methods.— Ever  since    Mr. 
Alpheus  Williams  read  his  paper  on  certain 
features  of  Kimberley  mining  practice,  Rand 
engineers  have  been  at  great  pains  to  demon- 
strate the   difficulties  and    drawbacks   to    be 
faced  in  applying  De  Beers  methods  to  the 
Rand.     As  the  paper  dealt  particularly  with 
the  handling  of  "  large  quantities  of  ground  in 
the  minimum  of  time,"  it  is  certainly  unneces- 
sary to  discuss  the  application  of  Kimberley 
methods  to  mines  having  no  big  tonnages  to 
handle  ;  at  the  same  time  there  seems  no  rea- 
son to  demand  that  main  levels,  equipped  with 
electrical  locomotives  or  rope-haulage,  must 
necessarily  serve  such  great  quantities  of  rock 
as  in  De  Beers  in  order  to  prove  an  economi- 
cal innovation.  The  tendency  of  critics,  more- 
over, has  been  to  view  the  "  main  haulage  " 
idea  too  much  in  the  light  of  normal  Rand 
practice,  and  too  little  in  its  relation  to  adapted 
schemes  of  development,  in  the  big  amalga- 
mated areas  of  today  and  tomorrow.     E.  J. 
Laschinger,  the  well  known   Corner   House 
engineer,  has  reviewed  Mr.  W^illiams'  paper  in 
a  spirit  of  fair  criticism,  but  his  cautious  argu- 
ments clearly  indicate  strong  bias  against  "ela- 
borate main  haulage  systems  underground." 
Heremarks:  "The time-honoured living-from- 
hand-to-mouth  policy  is  one  that  has  points  in 
its  favour,  because  it  is  a  gold  or  ready  cash 
industry.     Our  gold  mines  never  have  a  slack 
time  of  production,  when  one  can  quietly  in- 
troduce changes  and  elaborate  improvements." 
It  is  perhaps  a  little  misleading  to  accuse  the 
Rand,  with  its  big  ore  reserves,  of  following  a 
"hand-to-mouth   policy,"    though    Mr.    Las- 
chinger's  meaning  can  be  easily  grasped.   The 
mills  have — often  with  good  reason — been  fed 
from  many  scattered  places  and  the  introduc- 
tion of  a  policy  demanding  concentration  has 
been  impossible.      But  must  these  conditions 
always  prevail  ?      Is  the  big  mining  area  to 
remain  a  mere  conglomeration  of  little  units, 
with  amalgamation  represented  by  the  erec- 
tion of  a  joint  office,  or  are  the  underground 
workings  to  be  made  to  feel  the  intluence  of 
the  big  tonnages  required  at  a  common  point  ? 
Whether  your  property  is  producing   10,000 
tons  per  month  or  100,000  tons,  your  breaking 
cost  will  remain  unaltered,  for  it  is  dangerous 
to  economize   in   official  supervision  over  a 
given  number  of  stope-faces  and  the  individual 
stope  efficiencies  will  be  unchanged.     Mani- 
festly it  is  in  tramming,  hoisting,  and  pump- 
ing that  underground  economies  must  be  at- 
tempted and  it  is  by  concentration  that  it  can 
be  done. 


26 


THE    MINING    MAGAZINE 


Miner's  Phthisis. — The  Government  has 
done  wisely  in  appointing  a  commission  of 
medical  men,  with  strong  powers,  to  investi- 
gate the  question  of  miner's  phthisis,  especi- 
ally in  relation  to  the  extent  to  which  the  dis- 
ease prevails.  The  body  comprises  Visser, 
S.  V.  van  Niekerk,  R.  Daly,  E.  Baumann, 
L.  G.  Irvine,  and  G.  D.  Maynard,  men  who, 
if  notall  adequately  equipped  with  aspecialist's 
knowledge  of  miner's  phthisis,  will  at  least 
arrive  at  sound  decisions.  For  this  we  may 
well  be  thankful  in  days  when  the  crank  is 
allowed  to  assume  high  status  in  public  in- 
fluence and  when  the  afflictions  of  the  miner 
are  often  exploited  for  selfish  political  pur- 
poses. 

Quality  or  Quantity.— It  was  surprising 
that  Dr.  Moir,  as  President  of  the  Chemical 
Metallurgical  and  Mining  Society,  and  one  of 
the  best  scientists  in  the  country,  should  have 
found  occasion  to  congratulate  the  Society 
upon  the  record  bulk  of  its  April  journal.  It 
is  time  that  the  Society  exercised  greater  dis- 
cretion in  the  publication  of  matter  and  re- 
sorted to  a  policy  of  severe  selection.  The 
low-grade  big  tonnage  idea  can  be  carried  to 
excess  in  literary  as  in  mining  work.  I  have 
already  referred  to  some  of  the  errors  and 
weaknesses  in  Mr.  Schmitt's  paper  on  *  Future 
Economies  in  Rand  Reduction  Plants,'  which 
accounts  for  28  pages  of  the  '  record  '  journal, 
and  there  is  no  need  to  continue  the  discussion 
of  the  theme.  It  need  only  be  added,  in  re- 
gard to  the  question  of  bulk,  that  several  of 
the  theoretical  flow-diagrams  could  have  been 
omitted,  and  that  there  was  much  superfluous 
reading  matter,  based  on  a  multiplicity  of 
minor  modifications  of  a  general  scheme. 
These  criticisms  are  made  in  no  carping 
spirit,  for  all  members  of  the  Society  must 
recognize  the  excellent  work  done  by  the 
editorial  committee  in  putting  together  a  use- 
ful publication  and  especially  in  compiling  ab- 
stracts from  current  technical  literature,  with 
the  discretion  displayed.  It  is,  indeed,  for 
members  themselves  to  see  that  their  con- 
tributions are  brief  and  thoroughly  to  the 
point.  It  may  be  mentioned  incidentally  that 
the  Geological  Society  of  South  Africa  is  also 
an  open  society,  without  demands  for  qualifi- 
cations of  membership,  and  that  any  member 
is  permitted  to  read  a  paper  or  criticism  at  its 
meetings.  But  this  does  not  mean  that  every 
paper  is  published.  Keen  scrutiny  is  exer- 
cised when  this  critical  stage  is  reached,  with 
the  result  that  this  society  presents  trans- 
actions to  the  world  that  are  a  lasting  credit 
to  science  in  the  Transvaal.  There  is  no  need 


for  the  C.  M.  &  M.  Society  to  adopt  such 
stringent  measures,  but  my  plea  is  for  the 
discouragement  of  length  in  papers,  unless 
this  feature  is  commensurate  with  the  subject 
discussed.  By  repeating,  with  insignificant 
alterations,  tables  and  diagrams,  and  padding 
out  the  descriptive  matter  with  a  host  of  re- 
servations, all  records  as  regards  the  weight 
of  journals  could  be  easily  surpassed.  Or,  if 
necessary,  the  society  could  fall  back  on  the 
accepted  method  of  expanding  its  publica- 
tions and  printer's  bill  by  publishing  in  Eng- 
lish and  Dutch. 

Single-Stage  v.  Double-Stage. —  In  a 
contribution  apparently  more  influenced  by 
personal  animus  than  a  desire  to  advance 
technology,  H.  Stadler  has  criticized,  in  un- 
sparing terms,  the  well-meant  paper  noted  in 
the  preceding  paragraph.  Mr.  Stadler  is  one 
of  the  principal  exponents  of  the  single-stage 
crushing  policy  as  opposed  to  the  newly  de- 
veloped double-stage  system,  now  accepted  in 
the  design  of  all  new  plants,  and  although 
generally  most  thorough  in  his  investigation 
of  details,  is  apt  to  flounder  in  his  broader 
inferences.  For  example,  he  now  states : 
"  In  face  of  the  fact  that  the  New  Kleinfon- 
tein  mine,  run  on  conservative  lines  with 
single-stage  crushing,  without  tube-mills,  ac- 
cording to  the  report  for  1910,  still  holds  the 
record  in  reduction  costs  (4s.  6'7d.  with  94'5% 
extraction  on  466,882  tons  per  year)  against 
two  of  the  largest  progressive  mines  (East 
Rand  Proprietary,  5s.  5'8d.  with  92'85%  ex- 
traction on  2,126,324  tons,  and  Crown  Mines, 
5s.  9d.  with  96'2%  extraction  on  1,511,658 
tons),  I  cannot  help  feeling  that  metallurgical 
business  on  the  Rand  has  become  too  refined, 
and  that,  from  the  introduction  of  the  cyanide 
process  to  the  present  date,  very  little — if  any 
— real  economical  progress  has  been  made." 

Debate  on  this  unusual  belief  would  merely 
lead  to  a  most  unprofitable  argument  on  the 
definition  of  terms,  but  the  foundation  for  the 
idea  expressed  is  clearly  fragile.  A  compari- 
son of  the  reduction  costs  taken  from  the 
annual  reports  of  the  New  Kleinfontein  and 
Crown  Mines  is  of  small  significance  for  the 
following  reasons  : 

(1)  The  mines  belong  to  diff"erent  groups 
and  there  may  be  considerable  differences  in 
allocation  of  costs. 

(2)  The  New  Kleinfontein  operates  one 
mill  and  the  Crown  Mines  three,  whose  costs 
are  individually  different  and  which  include 
the  comparatively  inefficient  old  mill  of  the 
Crown  Reef. 

(3)  The    distinctions  in    the    character   of 


JULY,    1911 


27 


East  Rand  and  Central  Rand  ore  are  prob- 
ably sufficient  to  account  for  a  substantial 
difference  in  milling  efficiency.  The  New 
Modderfontein  mine,  also  in  the  Far  East 
Rand,  is  very  much  lower  in  reduction  cost 
than  the  average  of  the  Eckstein  mines,  whose 
expenses  are  all  kept  on  a  uniform  basis. 


Sand-Filling  at  the  Robinson. 

Geldenhuis  Deep 
Sand -Filling.  —  The 

photograph  published 
herewith  shows  the 
sand-residue  dump 
from  which  the  Gel- 
denhuis Deep  draws  its 
material  for  stope-fill- 
ing.  The  experimental 
scheme  for  filling  the 
trucks  involves  the  use 
of  the  tunnel  under  the 
dump,  the  mouth  of 
which  appears  in  the 
picture.  The  trucks  are 
run  in  and  are  filled 
through  an  opening  in 
the  top  of  the  close-tim- 
bered tunnel,  like  the 
bottom  discharge-door 
of  a  cyanide-vat. 

Coloured  Wrap- 
pers for  Explosives. 
— It  is  reported  that  a 
thorough  test  of  the  ad- 
vantages to  be  gained  by  the  use  of  coloured 
wrappers  for  explosives  is  to  be  made  on 
several  mines  and  on  a  scale  that  will  at  least 
ensure  the  issue  of  weighty  opinion  based  on 
practical  experience.  The  benefits  of  this 
scheme,  which  promises  to  effect  the  readier 


detection  of  unexploded  gelatine  in  the  stopes, 
amid  the  broken  greenish  -  grey  rock,  have 
often  been  advanced.  It  is  not  that  the  paper 
will  frequently  be  found  adhering  to  the  cart- 
ridge, but  its  detection  anywhere  will  be  a 
warning.  The  extra  cost  will  be  trivial  and 
the  results  of  the  scheme  will  be  appreciably 
in  the  right  direction. 

Average  Depth  of  Ore  Hoisted.— Al- 
though a  vastly  simpler  question  than  the  de- 
termination of  the  average  grade  of  Rand  ore 
for  various  depths,  the  average  depth  from 
which  rock  is  today  being  hoisted  is  neverthe- 
less difficult  to  ascertain  without  obtaining 
foot-ton  statistics  from  all  individual  mines. 
An  engineer  has  recently  advanced  the  esti- 
mate of  2400  ft.  as  the  average  depth,  but  the 
basis  of  the  estimate  was  obviously  faulty. 
The  figure  named  is  certainly  excessive.  Al- 
though producing  no  conclusive  result,  it  is 
suggestive  to  note  that  over  80%  of  the  Rand's 
ore  is  obtained  from  mines  that  do  practically 
no  stoping  below  2400  ft.  vertical,  while  about 
25%  is  drawn  from  mines  with  no  stopes  be- 
low 1000  ft.  vertical.  Assuming  these  last 
work  at  an  average  depth  of  600  ft.,  that  the 


Geldenhuis  Deep  Sand-Filling. 

balance  of  the  80%  is  from  1200  ft.,  and  that 
the  ore  from  mines  with  stopes  deeper  than 
2400  ft.  comes  from  an  average  of  3000  ft., 
we  get  a  general  average  of  1410  ft.  Allowing 
for  development  rock  drawn  from  deeper  levels 
than  the  stopes,  a  fair  working  figure  of  1500 


28 


THE    MINING    MAGAZINE 


ft.,  average  vertical  depth,  is  arrived  at.  A 
detailed  investigation  of  conditions  in  certain 
important  areas  proves  this  estimate  to  be 
highly  reasonable.  The  average  depth  will 
increase  steadily  and  surely,  but  the  speed 
will  be  slow  under  present  conditions.  The 
increasing  scale  of  operations  in  such  outcrop 
mines  as  the  Randfontein  Central,  Modder- 
fontein,  Modder  B,  Bantjes,  the  Paarl  Cen- 
tral and  Langlaagte  Royal  belonging  to  the 
Crown  Mines,  and  the  Benoni  Consolidated 
will  tend  further  to  restrain  the  rate  of  in- 
crease in  average  working  depth.  A  strip  of 
ore  along  the  Rand  from  Modderfontein  to 
Randfontein,  equivalent  to  a  vertical  drop  of 
500  ft.,  would  contain  over  125,000,000  mill- 
ing tons.  Judging  by  the  tendencies  of  pre- 
sent expansion,  it  will  be  fully  five  years  be- 
fore the  average  of  ore  mined  exceeds  2000 
ft.  vertical. 

Corner  House  Policy.  —  Mr.  Lionel 
Phillips  took  advantage  of  the  East  Rand 
Proprietary  meeting  to  place  on  record  his 
official  views  as  to  the  most  profitable  policy 
to  be  pursued  in  modern  Rand  mining,  and 
most  emphatically  gave  his  support  to  the 
camp  of  wholesale  miners,  whose  colours  have 
been  rudely  tattered  during  the  past  year  by 
a  transient  whirlwind  of  higher  economics. 
Mr.  Phillips  discussed  the  opposition  policy 
of  working  out  the  richest  areas  first,  in  a 
striking  way,  and  declared :  "  If  in  the  mines 
they  could  pick  out  certain  bags,  as  in  a  ware- 
house, and  sample  them  as  required,  the  policy 
of  working  the  rich  ore  first  would  unques- 
tionably be  the  right  one."  He  urged  that 
the  soundest  policy  would  be  to  "  disregard 
as  much  as  they  could  the  question  of  unpay- 
able ground  " — this,  of  course,  only  in  asso- 
ciation with  operations  on  a  big  scale.  The 
meaning  of  this  '  disregard '  for  the  question 
of  profit  is  clear  enough  and  indicates  that, 
with  milling  capacity  beyond  the  standard  of 
payable  ore  reserves,  the  "  borderland  "  blocks 
will  be  worked  or  tested  by  stoping,  and  will 
be  neglected  only  where  they  have  been  de- 
finitely proved  to  be  unprofitable  by  adequate 
work.  Mr.  Phillips'  statement  should  have  a 
reassuring  effect. 

Electrification, — One  of  the  most  impor- 
tant papers  read  before  a  South  African  tech- 
nical society  for  many  months  was  delivered 
by  T.  P.  E.  Butt  on  May  13  at  the  S.  A.  In- 
stitute of  Engineers,  describing  in  detail  the 
electrification  of  the  Randfontein  Central. 
The  value  of  such  a  paper,  full  of  facts  and 
devoid  of  fancies,  read  at  a  time  when  electri- 
fication from  central  power-stations  is  a  mat- 


ter of  general  concern,  cannot  be  over-esti- 
mated, from  the  standpoint  of  practical  edu- 
cation. The  power  station  of  the  Randfon- 
tein Central  has  been  designed  to  meet  the 
demands  of  maximum  sustained  loads  amount- 
ing to  14,000  hp.,  of  which  6900  hp.  is  in  re- 
spect of  mining  plant,  including  hoists,  pumps, 
and  compressors.  The  company's  old  power- 
station  of  2000  kw.  capacity  has  been  in- 
creased to  20,000  kw.,  by  the  addition  of  three 
2000  kw.  sets,  and  two  6000  kw.  sets.  Mr. 
Butt  summarizes  the  general  features  of  the 
plant  by  noting  that  the  scheme  involves 
generating  and  transmitting  at  6600  volts, 
3  phase,  50  cycles  ;  distributing  at  2200  and 
500  volts  for  motors,  with  further  transfor- 
mation to  120  volts  for  lights  and  underground 
pump-motors;  the  addition  of  underground 
cables  as  a  means  of  transmitting  and  dis- 
tributing ;  the  adoption  of  turbines  of  the  re- 
action type  as  the  prime  movers  ;  and  the 
adoption  of  a  straight-tube  boiler  with  pro- 
vision for  mechanical  firing  and  consuming 
the  cheapest  coal  obtainable.  Covering  the 
subject  in  detail,  the  paper  is  obviously  not 
one  to  stand  condensation.  A  section  of  pecu- 
liar interest  is  that  dealing  with  capital  and 
running  costs.  It  is  stated  that  actual  ex- 
penditures came  within  3%  of  the  estimate, 
which  was  as  follows  : 

Boiler-plant  ^121,000 

Cooling-tower,  piping  and  launders  13,000 
Generator  and  condensing  plant....       97,000 

Substations 24,000 

Transmission  cables 21,000 

Buildings 11,000 

Workshops,  artesian  wells,  etc 16,000 

;^303,00O 
Taking  the  power-station  alone  and  including 
the  cost  of  the  first  section  of  the  plant,  this 
works  out  at  ^16  per  kw.  of  plant  installed. 

The  working  costs  for  March  1911  were  as 
under : 

Pence 
per  unit 

Coal 0*153 

Repairs  and  maintenance 0'046 

Salaries  and  wages 0"035 

Oil,  waste,  and  stores 0'003 

Office  and  general 0'007 

0*247 
In  this  month,  5,085,430  units  were  generated, 
which,  deducting  auxiliaries,  left  4,678,570 
units  for  distribution  at  the  switch-board. 
Lower  costs  will  be  attained  under  the  best 
working  conditions,  which  did  not  prevail  in 
March. 


JULY,    1911 


29 


Giesecke  Tube-Mill.  —  Hitherto  the  old 
mill  on  the  Geldenhuis  Estate,  on  the  ridge 
commanding  the  Bezuidenhout  valley,  has 
gained  distinction  as  one  of  the  only  batteries 
on  the  Rand  to  possess  sufficient  natural  fall 
to  obviate  the  mechanical  elevation  of  tailing. 
It  has  now  sprung  into  sudden  renown  on 
account  of  the  trials  being  made  therein,  by 
the  Mines  Trials  Committee,  of  the  newly 
introduced  Giesecke  tube  or  ball  mill.  It  is  as 
yet  too  early  to  speak  with  satisfactory  finality 
as  to  the  possibilities  of  this  one-stage  crush- 
ing machine.  But  as  so  much  attention  has 
been  directed  to  its  initial  runs  and  such 
revolutionary  consequences  have  been  sug- 
gested in  high  quarters,  some  preliminary 
notes  must  be  given  and  some  opinions  risked. 
The  mill,  similar  in  general  appearance  to  the 
common  tube-mill,  is  over  24  ft.  long.  The 
feed  end  of  the  tube  is  of  greater  diameter 
(7  ft.  6  in.)  for  a  length  of  6  ft.,  than  the  re- 
maining 18  ft.,  which  main  portion  is  approxi- 
mately 6  ft.  in  diameter.  The  mill,  charged 
with  steel  balls  (eight  sizes)  of  diminishing 
weight  from  feed  to  discharge,  rotates  at  24 
r.p.m.  The  feed  end  or  breaking  compart- 
ment is  of  bigger  diameter  and  receives  ore 
direct  from  the  breakers,  of  a  size  fit  for 
stamp-milling.  The  final  discharge  is  said  to 
contain  81%  minus  200  mesh  material  and  only 
0'5%  of  60  mesh,  an  '  all-slime  '  product.  A 
duty  of  360  tons  per  day  is  claimed,  but  more 
convincing  statements  are  required  on  this 
point,  not  only  to  indicate  the  duty  in  the 
initial  runs  but  also  when  wear  and  tear  have 
played  their  part.  A  boast  is  made  of  the 
mill's  ability  to  do  the  work  of  stamps  and 
tube-mills,  the  crushing  and  the  grinding,  in 
one  operation.  In  itself,  this  advantage  is 
small.  A  simplification  is  of  no  importance 
unless  associated  with  reduced  cost.  The 
fact  that  the  mill  is  consuming  much  power 
in  rotating  a  quantity  of  sand  and  slime,  pro- 
duced in  the  first  chamber,  and  requiring  no 
further  pulverization,  in  its  passage  through 
the  body  of  the  mill,  suggests  useless  work. 
The  employment  of  independent  units,  stamps, 
and  tube-mills,  allows  of  a  classification  of 
products  that  prevents  this.  However,  the 
true  significance  of  these  points  will  appear 
when  trustworthy  data  are  made  available. 
In  the  meantime,  the  mechanical  engineers 
(who  are  supporting  the  scheme  rather  than 
the  seasoned  metallurgists,  with  in  whose  sphere 
such  experimenting  properly  lies)  would  do 
well  not  to  commit  themselves  too  loudly  as 
to  the  success  of  the  trials.  First,  let  them 
recognize  that  the  consumption  of  steel  has 


been  the  principal  crux  of  wet  ball-milling 
practice  all  the  world  over,  and  secondly  that 
the  Rand  is  equipped  with  reduction  plants, 
to  the  value  of  many  millions  sterling,  from 
which  the  last  results  have  still  to  be  obtained, 
whatever  economies  can  be  claimed  by  the 
Giesecke  mill.  An  apparently  strong  case 
has  already  been  made  out  in  regard  to  saving 
of  capital  expenditure,  but  this  comparison, 
after  all,  depends  upon  the  duty  maintained, 
and  the  figures  here  require  substantiation. 
As  for  running  costs,  no  authoritative  state- 
ment can  be  made  till  we  know  the  consump- 
tion of  steel  in  balls  and  lining  per  ton  of 
average  deep-level  ore  crushed. 

NEW  YORK. 

The  stock  market  remains  almost  fea- 
tureless. Of  course,  a  certain  amount  of  en- 
thusiasm was  manifested  as  soon  as  the  legal 
status  of  the  Oil  and  Tobacco  Trusts  was 
established  by  the  Court,  and  mining  shares 
participated  with  others  in  a  sudden  burst  of 
activity,  with  rising  prices.     Prices  still  hold 


Maztimn,  Xevadti. 

up  well,  but  the  volume  of  business  is  small. 
Within  the  past  month.  Amalgamated  has  ad- 
vanced 3i;  Miami,  If;  Tennessee  Copper, 
3f ;  and  Utah  Copper,  Si-  Goldfield  Con- 
solidated and  Nevada  Consolidated  likewise 
record  an  impro\'ement  over  a  month  ago, 
but  to  a  less  extent.  Although  the  Trust  de- 
cisions left  no  uncertainty  as  to  the  illegality 
of  the  two  great  offenders,  which  were  an 
trial,  a  general  feeling  of  unrest  still  prevails 
among  those  who  manage  the  great  corpora- 
tions, and  this  is  due  probably  to  what  amounts 
practically  to  a  reversal  of  itself  by  the  Su- 
preme Court.  Not  so  many  years  ago,  in  a 
similar  case,  the  Court  went  on  record,  liter- 
ally, as  opposed  to  any  assumption  of  legis- 
lative power  through  reading  the  word  "  un- 


30 


THE    MINING    MAGAZINE 


reasonable  "  into  the  Sherman  Anti  -  Trust 
Act  as  an  adjective  qualifying  "  restraint  of 
trade  "  ;  the  same  Court  now  expresses  the 
opinion  that  the  Act  was  intended  to  apply 
only  to  such  actions  in  restraint  of  trade  as 
are  obviously  unfair,  "unreasonable,"  and 
opposed  to  common  justice.  This  leaves  the 
future  position  of  hundreds  of  other  corpora- 
tions still  open  to  suspicion,  and  until  the  fog 
is  still  further  cleared  away,  it  is  not  to  be  ex- 
pected that  many  new  enterprises  of  great 
magnitude  will  be  launched.  Investigation 
of  the  events  leading  up  to  the  consolidation 
of  the  Tennessee  Coal  &  Iron  Co.  with  the 
Steel  Trust  is  now  under  way  in  the  Senate 
and  many  of  the  leading  officials  of  the  com- 
panies are  being  given  an  opportunity  to  ex- 
plain an  apparent  breach  of  the  law.  As  to 
the  statement  that  the  consolidation  had  the 
approval  and  sanction  of  President  Roose- 
velt, it  is  now  generally  thought  that  the  facts 
may  not  have  been  put  before  him  in  their 
fullness,  and  that  certain  prognostications  as 
to  the  parlous  times  into  which  the  country 
and  the  steel  industry  were  drifting  were 
somewhat  overdrawn. 

Mexican  disorders  seem  in  a  fair  way  to 
be  settled  amicably.  The  attitude  of  Madero, 
the  leading  spirit  in  the  revolution,  is  winning 
much  applause,  the  more  so,  perhaps,  because 
his  willingness  to  remain  in  the  background, 
while  the  Government  was  being  readjusted 
along  constitutional  lines,  was  not  wholly  ex- 
pected. Sectional  disorders  are  still  rife,  and 
the  Government's  attempts  to  establish  pro- 
visional rule  in  many  of  the  States  are  not 
very  successful.  So  far  as  mining  is  con- 
cerned, the  revolution  has  not  caused  any 
serious  losses  or  delays.  The  express  com- 
panies, in  some  instances,  have  declined  to 
accept  consignments  of  bullion,  but  the  mines 
in  many  cases  have  made  the  shipments  at 
their  own  risk,  and  without  incurring  any  great 
loss.  Some  of  the  railroads  have  been  put  out 
of  commission,  but  these  will  quickly  be  re- 
paired and  mining  operations  ought  soon  to  be 
resumed. 

Tariff  reforms  are  still  under  discussion, 
but  no  final  action  has  yet  been  reached. 
The  actual  treaty  under  negotiation  relates  to 
Canada  alone,  but  if  this  is  approved  by  Con- 
gress, it  is  a  safe  prediction  that  other  similar 
treaties,  the  aim  of  which  will  be  to  reduce 
the  oppressive  and  preposterous  duties  levied 
by  the  Payne-Aldrich  law,  will  come  up  for 
consideration,  resulting,  it  is  to  be  hoped,  in 
a  general  breaking  down  of  the  barriers  exist- 
ing between  the  United  States  and  all  other 


countries.  The  farmers,  for  whose  benefit 
all  previous  tariff  impositions  have,  nominally, 
been  enacted,  are  beginning  to  realize  the 
hollowness  of  the  arguments  advanced  in  sup- 
port of  a  tariff  policy  of  protection,  and  are 
shifting  the  responsibility  to  the  manufac- 
turers, who  are  really  the  only  ones  benefited 
by  such  artificial  barriers.  The  treaty  with 
Canada  has  received  favourable  attention  in 
the  House,  and  while  it  is  being  unnecessarily 
delayed  in  its  passage  through  the  Senate,  all 
signs  seem  to  indicate  that  it  will  be  passed 
without  much  alteration. 

The  copper  market  shows  decided  marks 
of  improvement.  In  spite  of  the  addition  of 
new  metal  from  the  porphyry  mines,  and  the 
failure  of  private  agreements  to  curtail  output 
from  the  older  producers,  the  price  is  slowly 
climbing,  under  the  stimulus  of  heavy  buying 
in  Europe  ;  American  consumers  were  slow 
to  place  their  orders,  but  have  now  gone  into 
the  market  with  considerable  alacrity,  and 
Lake  copper  is  now  almost  touching  13  cents. 
If  general  confidence  in  business  affairs  is 
ever  restored,  and  a  few  of  the  long  projected 
installations  of  electric  traction  enterprises 
are  put  under  way,  the  market  will  show  im- 
mediate improvement.  In  this  connection,  it 
is  interesting  to  note  the  prevailing  low  price 
of  aluminium.  It  can  easily  be  computed  that, 
forelectric  transmission, aluminiumis  the  more 
economical  metal  whenever  it  can  be  bought 
at  less  than  twice  the  price  of  copper.  The 
best  ingot  aluminium  can  now  be  bought  for 
20  cents  per  pound,  and  the  demand  is  dull  at 
that  price.  It  looks  as  though  the  wire-makers 
were  neglecting  an  opportunity. 

MEXICO. 

After  the  Revolution.  —  The  railroad 
lines  recently  damaged  have  been  repaired, 
and  traffic  has  been  resumed.  However,  as 
much  of  the  repair  work  has  been  of  a  tem- 
porary nature,  it  is  feared  there  will  be  more 
traffic  interruptions  than  usual  from  wash- 
outs during  the  rainy  season  now  opening. 
Permanent  repairs  will  be  made  as  rapidly 
as  possible.  The  losses  sustained  by  the 
Southern  Pacific  have  been  placed  at  $500,000. 
No  estimates  of  the  losses  sustained  by  the 
National  Railways  of  Mexico  and  the  Mexico 
Northwestern  Railway  have  been  given  out. 
There  was  a  decrease  of  2,053,122  pesos  in 
the  earnings  of  the  National  Railways  for  the 
month  of  May.  The  Mexican  Express  Co., 
operating  on  the  merger  lines,  has  resumed 
the  handling  of  money  and  bullion.  Work- 
men at  the  Velardena  smelter  of  the  Ameri- 


JULY,    1911 


31 


can  Smelters  Securities  Co.,  at  the  Torreon 
custom  smelter,  and  at  the  Guggenheim  mines 
in  the  Velardena  district  of  Durango  recently 
went  on  strike  for  higher  wages.  Their  de- 
mands were  refused,  and  they  returned  to 
work  within  a  few  days.  These  strikes  were 
preceded  by  similar  strikes  at  the  Matehuala 
smelter  of  the  American  Smelters  Securities 
Co.,  and  the  Mapimi  smelter  of  the  Pefioles 
Mining  Co.  During  the  revolution  there 
gained  currency  among  Mexican  workmen  a 
report  that  in  the  event  of  Madero's  triumph 
employers  of  labour  would  be  forced  to  pay 
higher  wages,  and  belief  in  this  report  had 
much  to  do  with  the  strikes  mentioned.  The 
Chihuahua  smelter  of  the  American  Smelting 


report  that  the  Pearson  oil  interests  in  Mexico 
may  pass  into  the  hands  of  the  Standard. 
[The  Texas  Oil  Co.  is  controlled  by  John 
W.  Gates  and  John  F.  Harris,  of  Harris, 
Winthrop  &  Company — Editor.]  In  this  con- 
nection it  is  recalled  that  the  Pearsons 
were  very  close  to  the  Diaz  government, 
and  were  granted  valuable  concessions  by 
that  administration,  and  it  is  suggested  that 
if  they  are  now  desirous  of  disposing  of 
their  oil  interests,  the  recent  political  changes 
in  Mexico  may  have  something  to  do  with  it. 
The  Pearsons  entered  the  selling  field  in  com- 
petition with  the  Waters  Pierce  Oil  Co.,  a 
Standard  subsidiary,  in  1908,  and  the  follow- 
ing year  the  Mexican  Eagle  Oil  Co.  was  or- 


A   STREET  SCENE  IN   MEXICO. 


&  Refining  Co.  was  forced  to  shut-down  late 
in  May  because  of  fuel  shortage,  but  the 
period  of  idleness  was  brief.  Cananea  was 
without  railroad  communication  with  the 
United  States  during  part  of  May,  but  the 
fuel-oil  and  coke  supplies  of  the  Cananea 
Consolidated  (Greene-Cananea)  were  suffi- 
cient to  prevent  an  interruption  of  the  exten- 
sive operations  of  that  concern. 

Pearsons. — Investigation  of  the  holdings 
and  business  of  S.  Pearson  &  Son  and  the 
Mexican  Eagle  Oil  Co.  by  officials  of  the 
Texas  Oil  Co.  and  the  Gulf  Refining  Co., 
both  Standard  Oil  concerns,  has  resulted  in  a 


ganized  principally  as  a  marketing  concern 
for  Pearson  products,  although  at  the  time  it 
was  announced  that  the  new  company  would 
also  take  over  and  work  some  of  the  Pearson 
oil-lands  and  concessions.  Since  fhe  organi- 
zation of  the  Mexican  Eagle  Co.  there  lias 
been  a  bitter  fight  between  that  concern  and 
the  Waters  Pierce  for  control  of  the  oil  busi- 
ness of  Mexico,  and  consumers  have  benefited 
through  the  cutting  of  prices.  It  is  stated 
that  the  Mexican  company  now  controls 
nearly  40%  of  the  oil  business  of  the  country. 
Prior  to  the  time  that  the  Pearsons  entered 
the  Mexican  field  the  Waters  Pierce  was  in 


32 


THE    MINING    MAGAZINE 


complete  control,  and  its  yearly  profits  were 
very  large.  The  oil  supplies  developed  by 
the  Pearsons  in  the  Potrero  field  in  the  State 
of  Veracruz  within  the  last  few  months  have 
greatly  increased  the  value  of  their  holdings. 
During  the  progress  of  the  Madero  revolu- 
tion it  was  repeatedly  reported  that  the  revo- 
lutionists were  receiving  financial  aid  from 
the  Standard  Oil  Co.  A  formal  denial  of 
these  reports  was  issued  by  the  Standard 
some  time  ago,  and  since  the  cessation  of 
hostilities  Francisco  I.  Madero  has  stated 
that  he  received  no  financial  support  from  the 
United  States.  Guillermo  Landa  y  Escan- 
don,  Governor  of  the  Federal  District  during 
the  latter  part  of  the  Diaz  administration,  is 
president  of  the  Mexican  Eagle  Oil  Co.,  and 
the  directorate  includes  Lieut. -Col.  Porfirio 
Diaz,  son  of  the  former  President,  and 
Enrique  C.  Creel,  former  Minister  of  Foreign 
Affairs.  The  company  was  organized  with  a 
capital  of  25,000,000  pesos. 

Zacatecas.  —  The  revolution  interfered 
but  little  with  operations  in  the  Zacatecas 
district.  The  Zacatecas  Mining  &  Metallur- 
gical Co.,  organized  in  1909  to  work  the  San 
Cristobal  and  other  mines  in  the  '  gold  belt,' 
is  ready  for  milling,  and  expects  to  handle 
at  least  100  tons  daily.  The  company  re- 
modelled the  milling  plant  at  the  San  Cristo- 
bal mines,  and  built  a  cyanide  annex.  The 
properties  included  those  handled  twenty 
years  ago  by  Whitaker  Wright.  M.  E. 
MacDonald,  prominently  identified  with  the 
mining  and  milling  revival  in  the  Guanajuato 
district,  is  at  the  head  of  the  company.  The 
Santa  Rosa  Mining  Co.,  controlled  by  the 
Exploration  Co.,  of  London,  is  making  good 
progress  with  its  mill  plans  at  the  Santa  Rosa 
properties  in  the  Concepcion  del  Oro  district. 
The  company  will  operate  with  electric  power 
generated  by  a  gas-producer  plant.  The  San 
Carlos  Gold  Mines,  also  of  London,  has  tem- 
porarily suspended  operations  at  the  San 
Carlos  and  Mesquital  mines  in  the  Mesquital 
del  Oro  district,  pending  more  settled  con- 
ditions in  Mexico.  The  company  has  been 
milling  successfully,  and  has  plans  for  im- 
portant betterments. 

Parral. — This  important  district  in  Chi- 
huahua was  without  railroad  communication 
during  the  month  of  May  ;  nevertheless  the 
principal  milling  concerns  continued  to  oper- 
ate steadily.  Shipments,  of  course,  were 
affected.  The  Veta  Colorado  handled  over 
300  tons  daily  at  its  new  plant,  and  expects 
to  show  an  increase  this  month.  Milling 
gains  are  being  made  by  the   Palmilla.     An 


option  to  purchase  450,000  shares  of  Pal- 
milla at  $5  per  share  has  been  asked  by 
strong  financial  interests  of  the  eastern  part 
of  the  United  States,  and  it  is  believed  that 
a  sale  will  result. 

West  Mexican. —  Now  that  railroad  con- 
ditions are  again  normal,  the  West  Mexican 
Mines  Co.  will  resume  work  on  its  200-ton 
reduction  unit  at  its  mines  in  the  Guadalupe 
y  Calvo  district  of  Chihuahua.  Shipments  of 
machinery  for  the  plant  were  held  up  by  the 
cutting  of  railroad  lines. 

MELBOURNE. 

Zinc  Corporation. —  The  news  received 
in  Australia  from  London  that  the  Zinc  Cor- 
poration was  to  absorb  the  Broken  Hill  South 
Blocks  company  excited  a  great  deal  of  amused 
comment.  The  finance  involved  may  do  very 
well  for  London,  but  the  directors  would  be 
pretty  bold  who  would  come  out  here  with 
such  a  scheme  for  an  Australian-owned  com- 
pany. The  fact  that  has  to  be  established  is 
that  the  South  Blocks  mine  is  a  dividend- 
payer.  So  far  the  ups  and  downs  of  its  shares 
in  the  market  have  indicated  a  manipulative 
power  by  some  crowd  that  no  one  on  this 
side  of  the  equator  wishes  to  meet  in  the 
dark.  Here  the  policy  is  for  the  shareholder 
who  puts  up  the  cash  to  be  first  considered. 
So  far  is  that  principle  carried  that  in  most 
mining  companies  the  paid-up  and  the  con- 
tributing shareholder  get  the  same  amount  of 
dividend  though  the  contributing  shares  may 
be  only  paid-up  10s.  in  the  £.  If  this  treat- 
ment was  not  meted  out  the  chance  of  obtain- 
ing capital  for  mines  would  disappear  unless 
everyone  was  put  on  the  same  footing  so  far 
as  contributions  to  the  company  go.  Cash 
payment  would  be  made  for  a  claim  and  if 
calls  had  to  be  made  all  would  have  to  pay. 
That  the  ordinary  shareholder  in  the  Zinc  Cor- 
poration should  be  flooded  wMth  preference 
shares  and  have  to  carry  more  of  his  own 
class  of  scrip  for  the  prospect  of  what  he  may 
get  out  of  the  South  Blocks  mine  is  a  bit 
"over  the  limit"  according  to  Australian 
ideas.  When  the  Zinc  Corporation  was  in 
a  tangle  it  had  to  make  the  best  terms  it 
could  to  get  cash,  including  the  provision  that 
the  '  prefs '  were  to  be  refunded  their  capital. 
As  beggars  cannot  be  choosers,  so  the  terms 
had  to  be  swallowed  rather  than  a  reconstruc- 
tion faced.  The  '  prefs'  also  took  preferen- 
tial voting  power.  The  ordinaries '  really 
sold  their  birthright  and  apparently  would 
have  done  better  to  have  washed  their  hands 
of  the  whole  concern,  had  their  contracts  sold, 


I 


JULY,    1911 


33 


and  taken  their  dividend  in  that  way.  Share- 
holders here  await  the  justification  for  the 
amalgamation  and  they  also  resent  the  short 
notice  given,  a  fact  to  which  the  attention  of 
the  Legislature  may  be  directed  whenever 
Australia  succeeds  in  getting  a  Companies 
Act  for  the  whole  of  the  Commonwealth. 

Etheridge. — Developments  on  the  Ether- 
idge  field  in  North  Queensland  are  of  interest 
to  the  large  body  of  shareholders  in  the  Chil- 
lagoe  company  and  the  debenture-holders  in 
the  company's  railway  system.  This  is  be- 
cause the  Chillagoe  company  has  built  the 
railway  to  the  Etheridge  in  the  hope  of  finding 
there  supplies  of  ore  for  its  smelters.  The 
directors  also  are  taking  up  options  and  the 
company  has  already  done  a  certain  amount 
of  prospecting  work.  In  this  connection  great 
importance  attaches  to  the  recent  development 
at  the  Durham  Consols  mine,  at  Georgetown, 
where  the  lode  has  been  cut  at  750  ft.  This 
is  the  deepest  point  reached  in  the  district. 
The  lode  where  cut  was  4  ft.  wide  and  the 
directors  report  that  it  averaged  5  oz.  gold 
per  ton.  But  on  driving  north  and  south  the 
width  shrank  to  18  inches,  though  at  the 
bottom  of  the  drive  the  ore  was  a  good  deal 
wider.  Assay-values  still  remained  satisfac- 
tory though  not  so  high  as  in  the  first  cut. 
The  Etheridge  mine,  a  Chillagoe  flotation,  is 
interested  in  this  strike  because  of  the  pros- 
pects on  some  of  the  blocks  they  hold.  The 
fear  was  that  at  the  Etheridge  the  somewhat 
narrow  lode  formations  might  peter  out  at 
depth,  but  the  piece  of  evidence  furnished  by 
the  Durham  Consols  so  far  has  been  to  the 
contrary.  The  Chillagoe  has  also  interested 
itself  in  coal  areas  at  Mount  Milligan  in 
Queensland.  Recently  they  sent  J.  T.  Wat- 
son of  Sydney  to  examine  them.  Mr.  Watson 
has  since  been  interviewed  and  he  said  that 
he  was  most  favourably  impressed  with  what 
he  had  seen.  The  field  had  the  making  of  a 
large  coalfield,  as  the  coal-bearing  country  ex- 
tends over  an  area  of  30  square  miles,  and  in 
Mr.  Watson's  opinion  the  work  already  done 
by  the  Chillagoe  and  Irvinebank  companies 
was  quite  sufficient  to  justify  further  develop- 
ment on  a  large  scale.  In  his  report  he  was 
recommending  the  Chillagoe  company  to  push 
on  with  further  work. 

Great  Fitzroy.  —  Before  this  reaches 
London,  D.  P.  Mitchell  will  have  landed 
there  and  perhaps  have  disclosed  all  that  he 
thinks  of  the  Great  Fitzroy  and  its  lament- 
able failure.  In  looking  up  the  records  of 
the  past  one  finds  Government  geologists  and 
experts  like  F.  B.  Powell  declaring  that  they 


like  the  proposition  very  much  and  that  with 
proper  handling  it  will  make  a  big  and  profit- 
able mine."  Some  figured  the  recoverable 
values  at  62s.  and  costs  at  37s.  6d.  But  the 
price  of  copper  was  put  at  a  much  higher 
point  than  that  at  which  it  now  stands.  And 
it  has  been  demonstrated  that  what  may  be 
regarded  in  a  report  as  "recoverable  values" 
do  not  always  pan  out  as  such.  The  difficulty 
with  the  concentrating  mill  was  to  handle  the 
ore  at  all  profitably.  So  at  W.  J.  Loring's 
direction  it  was  shut-down  and  a  Minerals 
Separation  plant  was  installed.  This  experi- 
ment has  been  watched  with  the  utmost  in- 
terest by  metallurgists  who  united  in  hoping 
that  the  recovery  would  settle  all  doubt  as  to 
the  ability  of  the  flotation  process  to  deal  with 
low-grade  copper  ores.  It  can  be  asserted 
that  the  work  done  in  that  respect  has  not 
been  altogether  disappointing,  as  a  satisfac- 
tory recovery  of  copper  was  achieved.  But 
the  difficulty  that  has  not  yet  been  overcome 
is  to  save  the  gold.  The  loss  of  this,  from 
such  a  low-grade  ore  as  that  of  the  Great 
Fitzroy,  and  with  metals  at  the  present  figure, 
meant  financial  shortage  each  month.  So  the 
plant  has  been  shut-down,  save  the  furnace. 
This  means  that  the  better  ore  will  have  to 
be  utilized  and  as  that  is  low-grade  what  is 
left  will  need  exceedingly  close  treatment  if 
it  is  to  yield  a  profit,  unless  copper  should 
follow  in  the  wake  of  tin  and  advance  to 
record  prices. 

Broken  Hill. — The  record  of  the  Broken 
Hill  Block  10  mine  is  one  that  may  well  be 
quoted.  The  block  of  35  acres  was  the  bonanza 
of  the  field  outside  the  Proprietary  Company's 
three  big  leases.  It  was  owned  originally  by 
that  company  and  was  floated  with  a  capital 
of  ;^1,000,000  in  ^10  shares.  The  company 
was  incorporated  in  March  1888  and  ore  was 
struck  in  December  1889,  it  being  magnificent 
in  point  of  richness  in  silver.  To  March  31 
last  the  company  raised  1,940,322  tons  of  ore, 
of  which  it  concentrated  on  the  mine  1,817,315 
tons  and  sold  123,007  tons  of  crude  ore.  It 
still  has  a  reserve  of  550,000  tons  of  ore,  a 
good  deal  of  which  is  above  the  1000-ft.  level. 
The  gross  contents  of  the  ore  treated  was 
35,598,545  oz.  silver  and  350,838  tons  of  lead. 
In  addition,  the  zinc  contents  were  roughly 
330,000  tons.  The  gross  value  of  the  silver  and 
lead  alone  at  today's  prices  is  ^7,769,000  and 
the  total  dividends  paid  have  been  ^1,245,000 
or  an  average  for  2\h  years  of  /,'58,000,  one 
year  bringing  in  £'295,000.  The  working  capi- 
tal was  of  the  smallest  and  therefore  the  com- 
pany has  a  proved  a  splendid  investment. 


34 


THE    MINING    MAGAZINE 


METAL  MARKETS 

COPPER. 

Average  prices  of  cash  standard  copper : 
June  1911  May  1911  June  1910 

;^56.  9s.  lOd.     £S\.  8s.  7d.         £5%.  8s.  lid. 
The  course  of  prices  has  been  steadily  up- 
ward reflecting  the   more  hopeful  views  en- 
tertained as  to  trade  conditions  in  America. 
These  views  are  strengthened  by  ihe  further 
decrease  in  the  world's  stocks  as  revealed  in 
the  May  figures  of  the  American  Producers' 
Association  and  by  the  expanding  demand  from 
manufacturers  both  in  Europe  and  America. 
In  Europe  the  consumption  for  the  past   12 
months   was   504,191    tons,    compared    with 
391,243  for  the  previous  year.     In  America 
domestic  consumers  took  5418  tons  more  in 
May  than  in  April,  while  most  encouraging 
reports  are  received  as  to  June  deliveries.     A 
sign  of  reviving  confidence  is  the  increase  in 
interest  taken  by  private  speculators  who  are 
buying  quietly  on  every  decline  in  price.  There 
is  a  constant  though  unobtrusive  demand  in  in- 
fluential quarters  for  standard  sorts  that  be- 
tokens confidence  in  the  future  of  prices.   Pro- 
ducers have  raised  their  prices  for  electrolytic 
to  12f  cents  in  New  York,  and  as  they  have 
sold  well  during  the  past  few  months  and  are 
encouraged  by  the  promising  trade  outlook, 
they  are  able  to  remain  independent  for  some 
time.  A  further  rise  is  not  improbable.    Eng- 
lish prices  of  electrolytic  show  a  rise  of  £1 
during  the  month.  The  holidays  and  the  labour 
troubles  have  interfered  but  little  with  the  mar- 
kets.    Heavy  sales  of  Japanese  copper  have 
been  made  to  the  Chinese  government. 

TIN. 

Average  prices  of  cash  tin  : 
June  1911  May  1911  June  1910 

;^207.7s.9d.    ;^197. 15s.4d.     ;^148. 13s.  Id. 

This  market  has  again  passed  through  one 
of  those  spectacular  and  rapid  changes  for 
which  it  has  become  notorious  and  which 
gives  rise  to  so  much  difficulty  and  irritation 
to  legitimate  dealers  and  consumers.  Having 
once  more  lured  the  unwary  to  create  a  con- 
siderable bear  interest,  the  syndicate  gradu- 
ally proceeded  to  punish  them  by  establishing 
a  backwardation  of  no  less  than  ;^43,  and 
only  when  the  bulk  of  the  commitments  had 
been  cleared  off,  did  they  permit  more  normal 
conditions  of  business  to  prevail.  Consumers, 
reluctant  to  pay  the  enormous  premiums  ex- 
acted, had  kept  out  of  the  market,  and  when 
prices  fell  again  they  were  found  to  be  heavy 


buyers  especially  in  America,  and  absorbed 
large  quantities  of  the  metal.  The  amount  of 
solid  business  is  so  great  as  make  it  apparent 
that  the  world's  supplies  are  insufticient  for 
its  needs.  Every  fall  in  prices  witnesses 
heavy  purchases  by  the  trade,  and  the  fluctua- 
tions in  stocks  are  only  brought  about  by 
manipulation  of  prices.  Meantime  a  further 
upward  movement  seems  inevitable. 

LEAD. 

Average  prices  of  soft  lead  : 
June  1911  Mav  1911         June  1910 

;^13.  5s.  5d.      ^12.  19s.  2d.  ^12.  13s.  9d. 

Lead  has  been  scarce  and  buyers  clamorous 
for  supplies ;  prices  consequently  have  been 
buoyant.  The  consumption  shows  expansion 
and  the  usual  sources  of  supply  have  been  in- 
sufficient for  the  London  demand,  so  that 
American  refineries  have  been  called  upon  to 
make  up  the  shortage.  The  stocks  there  are, 
however,  greatly  depleted,  and  in  view  of  the 
curtailment  of  the  Mexican  supplies  it  seems 
doubtful  whether  they  will  continue  to  pro- 
vide the  tonnage  they  have  been  sending. 

SPELTER. 

Average  prices  of  ordinary  brands  : 
June  1911  May  1911  June  1910 

^"24.  9s.  7d.      ^24.  6s.  Id.      ;^22.  3s.  2d. 

Further  increase  in  the  production  of  this 
metal  seems  impossible,  as  the  existing  works 
are  at  their  fullest  capacity  and  are  unable  to 
cope  with  the  demand.  The  quantities  of- 
fered by  the  syndicate  are  being  narrowed 
down  as  much  as  possible  and  prices  have 
been  raised  a  further  5s.  per  ton  ;  but  the  de- 
mand keeps  growing,  and  the  galvanized  iron 
trade  is  expanding  in  a  way  that  could  never 
have  been  foreseen. 

OTHER  METALS  AND  MINERALS. 

Prices  quoted  on  July  10  : 

Silver. — 24id.  per  oz. 

Platinum. — 172s.  6d.  per  oz. 

Bismuth. — 7s.  6d.  per  lb. 

Aluminium. — £b\  per  ton. 

Nickel. — ^^169  per  ton. 

Cobalt. — 9s.  9d.  per  lb. 

Antimony. — ;^29  per  ton. 

Quicksilver. — ^8.  5s.  per  flask  of  75  lb. 

Manganese  Ore. — 9d.to9jd.  per  unit  (1%). 

Iron  Ore. — Cumberland  hematite  19s.  6d. 
per  tonatmine.  Spanish  19s.deUveredin  Eng- 
land. 

Pig  Iron. — Cleveland 46s. 6d. per  ton.  He- 
matite 62s.  per  ton. 

Wolfram  Ore— 31s.  per  unit  (1%). 


JULY,    1911 


35 


DISCUSSION 

Our  readers  are  invited  to  criticize  anything  appearing  in  this 
magazine  and  to  discuss  other  subjects  of  general  technical 
interest. 

Tube-Mill  Lining. 

The  Editor  : 

Sir — The  accompanying  photograph  shows 
the  way  in  which  the  pebbles  set  themselves 
in  the  ribs  of  the  cast-iron  liners  placed  inside 
the  shell  of  the  tube-mill,  thus  forming  the 
well  known  El  Oro  type  of  liner.  In  this  par- 
ticular case  the  tube-mill,  16  ft.  long  by  3  ft. 
6  in.  inside  diameter,  is  part  of  the  equipment 


at  the  mill ;  about  25%  of  weight  is  lost  in  the 
grinding  ;  2  pesos  will  cover  the  power  and 
labour ;  so  that  they  may  be  produced  for 
about  12  pesos  (24  shillings)  per  ton. 

Imported  Danish  pebbles  would  cost  about 
90  pesos  {£9}  per  ton  at  Tampico ;  mule 
freight  of  50  pesos,  with  rail  freight  to  Parral 
and  agent's  charges  would  bring  the  cost  to 
over  150  (£15)  per  ton,  so  that  the  large  saving 
more  than  counterbalances  the  slight  inferi- 
ority of  this  pebble  as  obtained  locally. 

A.  N,  Mackay. 

Wimbledon,  May  2. 


TUBE-MILL    LINING. 


of  the  La  Ceniza  mill,  situated  about  40  miles 
east  of  Guadelupe  y  Calvo,  the  ancient  capital 
of  the  State  of  Chihuahua,  Mexico.  All  sup- 
plies have  to  be  carried  on  mules  from  the 
nearest  railroad,  the  Ferrocarril  Parral  y 
Durango,  at  a  cost  of  50  pesos  (£5)  per  ton, 
8  or  10  days  being  occupied  in  the  transport. 
To  effect  a  reduction  in  the  working  cost  a 
successful  attempt  was  made  to  obtain  a  suit- 
able pebble  on  the  mine.  The  central  portion 
of  the  vein  being  worked  is  an  extremely  hard, 
whitish,  chalcedonic  quartz,  in  places  having 
the  appearance  of  true  flint,  in  others  it  is 
banded  like  agate.  It  is  quarried  at  the  most 
suitable  places  along  the  outcrop,  the  large 
pieces  being  reduced  by  hammers  to  the  re- 
quisite size  :  4-inch  cubes.  These  cubes  are 
filled  into  the  mill  without  water,  the  mill  is 
revolved  for  8  or  10  hours,  after  which  pebbles 
similar  to  those  shown  in  the  photograph  may 
be  taken  out.  The  contract  price  for  the 
cubes  is  8  pesos  (16  shillings)  per  ton  delivered 


Fine  Grinding. 

The  Editor  : 

Sir — In  an  article  in  your  IMarch  issue  on 
fine  grinding,  the  author,  Mr.  H.  S.  Denny, 
advocates  a  wider  application  of  the  method, 
and  predicts  its  almost  general  adoption  in 
the  future. 

After  defining  '  all-sliming  '  as  a  term  appli- 
cable to  the  grinding  of  an  ore  to  pass  100- 
mesh,  or  finer,  the  author  discusses  the  ques- 
tion of  the  limiting  factor  and  efficiency,  and 
defines  the  former  as  the  comparison  between 
"  the  added  cost  of  each  unit  of  fine  grinding, 
and  the  added  extraction."  This  is  a  vague 
statement  which  apparently  takes  notice  of 
increased  capital  necessary,  but  not  increased 
running  cost.  The  next  assumption  that  the 
author  wishes  to  allow  is  that  "  the  actual 
work  done  can  be  measured  against  an  accu- 
rate record  of  power  consumed  in  doing  that 
work."  This  is  also  vague,  but  I  presume 
that  the  author  is  confining   himself   to   the 


36 


THE    MINING    MAGAZINE 


question  of  power  consumption  and  means  to 
say  that,  as  regards  '  all-sliming,'  the  power 
consumed  by  the  classifying  and  re-grinding 
plant,  return-pumping  systems,  settlers,  agi- 
tators, and  filter-press  plant,  can  be  estimated 
more  or  less  exactly. 

We  next  come  to  a  theoretical  example 
of  the  advantages  that  Mr.  Denny  supposes 
would  accrue  by  the  adoption  of  '  all  sliming  ' 
in  the  case  of  a  simple  gold  ore  carrying  8 
dwt.  per  ton.  The  ore  in  question  is  a  silicious 
one,  containing  5%  pyritic  material,  90%  of  the 
latter  carrying  70%  of  the  gold.  This  material 
is  crushed  to  60-mesh,  and  it  is  next  assumed 
that  the  metallurgist  would  agitate  and  filter- 
press  this  product,  with  a  resultant  recovery 
of  only  80%.  According  to  Mr.  Denny  "  the 
question  would  then  arise  as  to  the  applica- 
tion of  finer  grinding,  and  in  what  particular 
form." 

The  next  assumption  is  that,  if  the  products 
were  re-ground  to  pass  200-mesh,  the  extrac- 
tion would  be  increased  from  80%  to  94%. 
The  extraction  from  the  original  slime  would 
remain  at  80%.  By  a  comparison  of  these 
figures  we  find  that  the  assumed  residue  re- 
sulting from  the  filter-pressing  of  sand  and 
slime  would  be  1"6  dwt.,  and  that  after  re- 
grinding  this  would  be  reduced  to  0"54  dwt., 
being  a  net  increased  recovery  of  about  1  dwt. 
per  ton.  This  profit  would  be  reduced  to 
about  0'3  dwt.  when  allowance  had  been  made 
for  the  extra  cost  of  re-grinding,  which  Mr. 
Denny's  experience  puts  at  3s.  per  ton. 

Later  in  the  article  the  author  admits  the 
impracticability  of  filter-pressing  a  mixture  of 
coarse  sand  and  slime,  and  we  are  therefore 
forced  to  the  conclusion  that  the  whole  argu- 
ment is  based  on  an  absurdity,  and  that,  had 
the  sand  been  leached  in  the  first  instance,  at 
a  fraction  of  the  cost  involved  in  agitation 
and  filter-pressing,  a  net  saving  in  favour  of 
separate  treatment  of  sand  and  slime  would 
have  been  the  result. 

Mr.  Denny,  in  an  attempt  to  justify  a  con- 
viction that  'all-sliming'  will  be  the  tendency 
in  the  future,  is  advocating  it  as  a  general 
method  and,  in  order  to  convince  his  readers, 
quotes  at  length  Mr.  Grothe's  excellent  sug- 
gestions as  regards  the  handling  of  treatable 
concentrate  in  an  'all-sliming'  plant.  This  is 
another  aspect  of  the  matter  altogether  and  is 
quite  distinct  from  the  idea  of  erecting  a  plant 
to  slime  sand  in  order  that  a  small  percentage 
of  concentrate  may  be  very  finely  ground. 

Fine  grinding  should  be  carried  to  such  a 
degree  that  subsequent  treatment  yields  the 
best  net  result  and  the  highest  net  profit.      If 


economy  and  improved  extraction  ensue  the 
concentrate  should  be  removed  (if  fine  grind- 
ing is  not  being  practiced)  and  treated  separ- 
ately. There  are  several  excellent  makes  of 
grinding-pans  that  have  proved  efficient  for 
the  grinding  of  concentrate  to  any  degree  of 
fineness.  The  practice  of  sliming  concentrate 
has  been  in  use  in  Western  Australia  for  a 
number  of  years,  and  has  given  excellent  re- 
sults at  a  minimum  of  cost,  the  agitated  con- 
centrate being  handled  in  the  presses  with  the 
ordinary  slime.  This  method  also  allows  for 
the  roasting  of  the  concentrate  beforehand, 
and  considerable  economies  have  been  shown 
to  result  from  the  adoption  of  the  latter  prac- 
tice, in  the  matter  of  subsequent  reduction  of 
cyanide  consumption.  Pachuca  tanks  have 
proved  most  efficient  for  the  agitation  of 
slimed  concentrate. 

Fine  grinding  is  as  obviously  necessary  for 
the  gold  ores  of  Kalgoorlie  as  it  is  for  the 
silver  ores  of  Mexico.  There  are  other  dis- 
tricts, however,  where  the  expenditure  is  not 
justified  by  the  results.  Mr.  Denny,  in  his 
article,  is  dealing  with  "  simple  gold  ores  " 
and  states  that  "  the  day  of  the  percolation 
method  of  treatment  for  sand  and  the  decan- 
tation  system  for  the  treatment  of  slime  has 
gone."  I  would  like  to  state  that  Rand  prac- 
tice is  not  universal  and  that  there  are  better 
and  more  up-to-date  methods  of  slime  treat- 
ment than  that  of  decantation,  and  that  these 
can  be  used  equally  well  for  handling  the 
slime  in  conjunction  with  the  percolation 
treatment  of  the  sand. 

In  spite  of  Mr.  Denny's  predictions,  I  have 
no  doubt  but  that  metallurgists  will  still  en- 
courage whatever  process  is  best  suited  to 
local  requirements,  and,  in  dealing  with  the 
fine  grinding  of  simple  gold  ores,  will  duly 
consider  whether  the  increased  yield  resulting 
from  its  adoption  is  in  due  proportion  to  the 
increased  capital  expenditure  and  the  neces- 
sarily higher  running  cost. 

A.  W.  Allen. 

Cufiapiru,  Uruguay,  May  6. 

Appointments  Vacant. 

The  Editor  : 

Sir — Could  you  find  space  in  your  valuable 
journal  to  comment  in  some  way  upon  the 
ridiculous  advertisements  that  so  often  appear 
under  the  above  heading  in  our  English  tech- 
nical journals  ? 

Vague  statements,  such  as  "  Metallurgist 
wanted  for  Timbuctoo.  State  experience  and 
salary  required,"  are  fairly  common.  Appli- 
cants are   expected   glibly    to    state  "  salary 


JULY,    1911 


37 


required  "  without  having  the  remotest  idea  of 
the  extent  of  their  duties  and  responsibilities 
or  for  what  kind  of  a  position  they  are  really 
applying.  It  is  our  English  firms  who  are 
the  chief  offenders  with  these  cheese-paring 
methods,  both  in  advertising  and  selection  of 
applicants.  "  Salary  required  "  is  more  often 
the  vital  question,  and  "  experience  obtained  " 
a  minor  and  unimportant  detail. 

R.  H.  B.  Butler. 
London,  June  22. 

[We    refer    to     this  subject  in   an   editorial 
paragraph, — Editor.] 

Mexican  Affairs. 

The  Editor  : 

Sir — I  again  take  the  liberty  of  submitting 
the  following  lines  to  rectify  some  groundless 
and  false  appreciations  contained  in  the  pages 
of  your  valuable  issue  of  January  last,  which 
I  have  just  perused. 

Therein,  Mr.  Theo.  van  Wagenen,  in  an 
article  styled  '  More  about  Mexico,'  presents, 
in  a  cursory  way,  his  views  on  the  political 
situation  of  my  country,  partaking  himself  of 
a  common  misconception  to  foreign  travellers 
and  even  to  residents  of  the  English-speaking 
class,  who  for  some  reason  seldom  come  in 
touch  with  well  informed  natives,  and  hold 
very  superficial  ideas  on  the  subject.  As  a 
result  of  this  lack  of  information,  the  history 
of  Mexico  becomes  rather  twofold. 

For  such  superficial  observers,  modern 
Mexico  and  Porfirio  Diaz  are  the  same  thing, 
the  latter  being  the  creator  of  the  former. 
They  suppose  that  when  General  Diaz  as- 
sumed power  in  1S76,  Mexico  was  quite  a 
barbarous  country  plunged  in  darkness  and 
strife,  a  land  wholly  insecure  for  life  and 
property,  and  that  Diaz  has  transformed  it 
into  a  hospitable  place  in  the  community  of 
nations. 

As  against  the  above,  history  itself  asserts 
that  in  1867,  when  Benito  Juarez,  the  greatest 
president  that  Mexico  ever  had,  passed  the 
penalty  of  the  law  on  Prince  Maximilian,  of 
the  Hapsburg  royal  blood,  Mexico  was  already 
a  civilized  country,  where  a  vast  number  of 
her  people  loved  peace  and  could  appreciate 
its  blessings.  From  the  year  1867  down  to 
1876,  it  was  General  Diaz,  the  only  revolu- 
tionist in  Mexico,  whose  ambition  for  power 
troubled  the  country. 

That  after  his  success  the  Mexican  people 
should  have  abided  by  his  autocratic  regime, 
cannot  properly  be  construed  a  blame  nor  a 
lack  of  patriotic  feeling  in  the  masses  ;  it  was 
the  reverse  ;  it  was  a  conscious  offering  in  the 


shrine  of  peace  ;  it  was  the  abdication  of 
political  liberties  for  a  time  for  the  sake  of 
national  welfare. 

Mr,  van  Wagenen  asserts  that  we  are  not 
worthy  to  control  our  own  country  ;  that  when 
General  Diaz  disappears  we  shall  be  like 
orphans.  This  disparaging  prediction,  if  it 
proves  anything,  only  proves  Mr.  van  Wage- 
nen's  ignorance  of  our  true  social  condition, 
and  I  sincerely  lament  that  such  erroneous 
statements  should  have  appeared  in  a  paper 
so  deservedly  esteemed  as  TJie  Mining  Maga- 
zine, for  they  may  elicit  the  suspicion  that  in 
other  matters  its  columns  could  be  equally 
misleadmg. 

Just  at  this  moment,  Sir,  the  Mexican 
people,  throughout  the  Republic,  are  cele- 
brating the  downfall  of  Diaz  and  his  exile 
under  the  ban  of  public  opinion.  This  is  the 
work  of  Mexican  patriots.  Yet,  we  have 
worthy  and  capacious  Mexicans  who  will  re- 
place him  in  power,  who  will  be  far  from  per- 
petuating his  autocratic  system  of  rule  ;  who 
will  uphold  the  laws  of  the  land,  and  while 
allowing  foreigners  to  partake  of  the  national 
wealth,  will  not  make  of  that  a  privilege.  The 
blame  that  Mr.  van  Wagenen  puts  on  Mexi- 
cans will  cease  henceforth,  and  a  new  era  of 
self-government  will  ensue. 

Lacking  the  necessary  time  to  refute  all 
the  pomts  in  Mr.  van  Wagenen's  long  stric- 
ture, I  will  but  refer  to  his  imputation  that  a 
return  to  the  old  revolutionary  days  in  Mexico 
would  join  the  upper  class  with  the  foreign 
element  in  a  demand  for  peace  at  any  price, 
even  if  that  price  should  be  the  extinction  of 
our  nationality.  W^here  has  Mr.  van  Wagenen 
resided  in  Mexico  to  forestall  such  public 
sentiment  ?  What  persons  are  those  whose 
acquaintance  he  has  made  to  warrant  his  un- 
qualified idea  ?  1 1  is  a  pity  to  see  your  worthy 
magazine  the  sponsor  of  these  paltry  absurdi- 
ties ! 

But  the  present  revolution  will  serve  to 
disprove  them.  Sir,  for  the  contending  par- 
ties, the  Government  class  and  the  revolu- 
tionist both,  have  repeatedly  disowned  the 
interference  of  a  foreign  power  in  their  domes- 
tic brawl.  To  be  sure,  the  large  majority  of 
the  nation  consider  the  preservation  of  national 
independence  as  the  highest  gift  they  possess, 
as  well  as  the  foundation  of  their  honour  as 
citizens  and  as  men,  any  affirmation  to  the 
contrary  being  fallacious,  and  too  destitute  of 
truth  to  arrest  the  attention  of  any  righteous 
sensible  person. 

Leopoldo  Salazar. 

Mexico  City,  May  28. 


38 


THE    MINING    MAGAZINE 


Calculations  of  Percentage  of  Recovery.. 

The  Editor : 

Sir  —  The  article  by  Mr.  Theodore  J 
Hoover  which  appeared  some  months  ago  in 
The  Mining  Magazine  has  already  had  a 
liberal  share  of  discussion  and  has  brought  an 
interesting  and  valuable  formula  to  the  atten- 
tion of  many.  Some  engineers  had  made  use 
of  a  similar  formula  in  calculating  or  check- 
ing their  mill-recoveries  and  have  mentioned 
the  fact  in  your  columns.  To  me  the  for- 
mula was  new  and  I  have  found  it  most  use- 
ful not  only  in  determining  the  total  extraction 
but  in  computing  the  recovery  made  by 
separate  concentrating  machines  such  as  a  jig, 
a  table,  or  a  magnetic  separator. 

In  making  tests,  however,  of  the  efficiency 
of  a  jig  or  of  a  table  concentrator  one  has  a 
middling  product  to  deal  with  which  is  not 
provided  for  in  the  Hoover  formula.  To  take 
into  account  this  middling  a  formula  has  been 
derived  as  follows  : 

.4  =weight  of  feed,  fi  =  weight  of  tailing. 
a  =  tenor     ,,     „     ,  b  =  tenor     ,,       ,, 
C  =  weight  of  concentrate,  D  =  weight  of 

middling. 
c  =  tenor  ,,  ,,  ,    d=  tenor  of 

middling. 
i?  =  Percentage  of  recovery. 

(1)  Aa  =  Cc  +  Dd-\-Bb 

(2)  A    =C  +  D  +  B 


(3)  R    = 


Cc 


Cc 


Aa     Cc^Dd  +  Bb 

Substituting  A  in  (l)  gives 

(4)  C  +  D  +  B  =  C?  +  d'^  +  B^- 


To  find  B  we  have 


a 


a 


D 


a 


a 


a 


^  a  ' 


B 


C(^-I)+Z,(f-,) 


a 

^(c  -a)-i-^{d-a) 
_  a a 

"  -^ 
a 

C  (c-a)  +  D  jd-a) 

a~b 
Substituting  B  in  (3)  gives 

Cc 


R  =■ 


Cc  +  Dd  + 


C{c-a)+D{d-a), 


Cc  ia-b) 


a  —  b 


This  is  a  formula  for  determining  the  re- 
covery, including  that  from  the  middling.  It 
is  necessary  only  to  weigh  the  product  and  the 
middling.  To  determine  the  weight  of  the 
material  treated  the  following  formula  was 
derived  : 

C{c-b)+D{d-b) 


=  A 


a 


Ca  ic-b)  +  Daid-b) 


In  this  it  is  also  necessary  to  know  the  weight 
of  the  product  and  middling. 

C.  W.  Wright. 
Pertusola,  June  16. 

The  Finance  of  a  Mine. 

The  Editor  : 

Sir — In  his  letter  of  last  month,  Mr.  Fern 
places  his  finger  on  several  features  the  defi- 
nition of  which  brings  out  sharply  the  differ- 
ence between  mining  as  an  industry  and  as  a 
convenient  means  of  public  exploitation  :  this 
is  the  perennial  fight  between  the  engineer 
bent  on  economics  and  the  engineer  inspired 
by  hope  of  promotional  favour. 

The  principal  points  raised  by  Mr.  Fern 
may  be  summed  up  as  follows  : 

(a)  The  scanty  nature  of  the  data  supplied 
to  the  mining  investor  ; 

(b)  The  technical  skill  required  to  interpret 
such  data ; 

(c)  The  difficulty  of  dealing  with  base-metal 
mines,  the  product  from  which  varies  greatly  in 
price  from  time  to  time  ; 

id)  The  definition  of  what  constitutes  a  re- 
serve, hence  the  '  life  '  allowance  necessary  ; 

(e)  The  dearth  of  maps  and  statements  of 
costs  and  losses  ; 

(/)  Methods  of  reporting  results  as,  for  ex- 
ample, from  vanning  and  chemical  analyses; 

(g)  Status  of  small  mines  as  regards  the  big 
properties. 

While  my  articles  will  deal  with  each  of 
these  points  incidentally,  I  may  say  now  that : 

{a)  There  is  no  justification  for  the  dearth 
of  data  supplied,  nor  is  this  a  matter  of  un- 
supported opinion,  for  many  companies  pub- 
lish full  reports  and  plans  :  fide  the  Great 
Boulder  Proprietary  Co.'s  annual  report  of 
1910,  where  the  position  andgeneral  allowance 
for  the  blocks  of  ore  classed  as  reserves  is 
shown  clearly  by  longitudinal  section.  By 
far  the  majority  of  mines  could  be  illustrated 
diagramatically  as  in  Fig.  A,  with  the  levels, 
winzes,  etc.,  shown  in  solid  lines  and  the  faces 
in  process  of  being  extended  by  broken  lines. 

The  outlook  of  the  mining  engineer  is  the 
resultant  of  at  least  three  powerful  forces, 
that  of  promotional  influences,  an  instruction 
that  subordinates  economics  to  technique,  and 


JULY,    1911 


39 


the  uncertainty  inherent  to  exploratory  min- 
ing. The  latter  acts  in  many  ways,  both  as 
tending  to  discourage  accuracy  in  thought  as 
well  as  commitment,  which  latter  may  after- 
ward be  used  in  censure.  In  general,  however, 
we  may  safely  say  that  the  modern  engineer 
is  willing,  in  fact,  would  take  pleasure  in  pre- 
senting full  detail,  but  this  is  not  usually 
favoured  by  financial  chiefs  except  in  the  case 
of  the  more  reputable  concerns.  The  miserable 


of  articles,  it  is  one  of  my  contentions  that 
most  mining  enterprises  in  any  stage  may  be 
regarded  as  an  industry  and  as  such  may 
have  its  salient  economic  points  set  out  on  a 
single  sheet  of  paper  as  concisely  as  an  or- 
dinary balance-sheet.  For  instance,  were  a 
half-yearly  or  even  a  yearly  diagram  like  F"ig. 
A  supplied  and  accompanied  by  a  tabular 
statement  of  assets  like  that  shown  in  Table 
B,  far  the   greater  part  of  mining  swindles 


2  A 

(rroSS  fcr/=  SOOOO 
Prcsen/  /a/  =     o 


3.  fl 

p.  y.  ^  A€  ooo 


5.  B       \     5.C  5  D 

\0l/    Zyo  oon     C  I/.  --  /2fl  ooo    C  V 
\fiV^/4l,coo    P  V -.    /4OO0    P  V. 


/3  ooo 


Fig,  A.     Solid  lines  indicate  work  accomplished.     Broken  lines  indicate  work  in  progress. 


Table  of  Assets  June  30. 


Table  B. 
Copper  calculated  at  ^60,  Silver  at  2s. 


Defer- 

No. of 

Tons  of 

Gross 

Net 

ence 

Risk  Rate 

Present 

Block 

Ore 

Value 

Value 

in 

used 

Value 

Remarks 

£ 

£ 

years 

£ 

2a 

50,000 

50,000 







_ 

2d 

110,000 

200,000 

90,000 

- 

5% 

83,000 

Four  sides  sampled 

2e 

90,000 

120,000 

30,000 

2 

7% 

23,000 

Three  sides  sampled 

3a* 

100,000 

175,000 

75,000 

3 

10% 

46,000 

Two  sides  sampled 

3b- 

90,000 

270,000 

180,000 

1 

10% 

141,000 

To  be  stoped  after  2  D : 
2  sides  sampled 

3c- 

80,000 

120,000 

40,000 

4 

20% 

14,000 

One  side  sampled 

3d* 

110,000 

175,000 

65,000 

5 

20% 

19,000 

One  side  sampled 

*In  practice  the  dimensions  allowed  this  block  would  be  governed  by  the  factors  represented 


by  Formula  X  of  the  second  article. 


'y- 


pretence  of  conciseness,  the  pitiful  drivel  of 
accuracy  shown  in  some  company  reports, 
with  pages  of  unedited  assay-returns,  is  a 
monument  to  incompetence,  while  being  at 
the  same  time  an  admission  of  the  justice  of 
the  demand  for  detail. 

As  will  be  demonstrated  later  in  the  series 
1—4 


would  become  a  memory  of  the  "  bad  old 
times,"  for  so  the  present  day  will  inevitably 
be  classed  a  few  years  hence,  because  of  our 
too  frequent  vicious  practices. 

(b)  With  reference  to  the  remark  that  tech- 
nical skill  is  required  to  decipher  mining  re- 
ports it  must  be  admitted  that  such  is  often 


40 


THE    MINING    MAGAZINE 


the  case,  but  this  is  not  inherent  to  the  busi- 
ness ;  lack  of  exactness  only  proves  that  the 
engineer  is  party  to  intentional  ambiguity  or 
is  wanting  in  that  sense  of  economic  propor- 
tion which  seeks  to  simplify  and  express  tech- 
nicalities in  monetary  units.  For  example, 
by  Fig.  A  and  Table  B  without  any  technical 
help  it  will  be  seen  what  development  of  the 
ore  has  been  accomplished  and  what  in  pro- 
gress :  what  ore  is  '  blocked '  (2  D)  and  the 
degrees  of  development  on  the  other  blocks  : 
the  gross  as  well  as  the  estimated  present 
value  of  each,  and  the  proposed  order  in  which 
to  work  the  blocks.  Thus,  on  account  of  the 
high  value  of  Block  3  B,  it  would  be  economi- 
cally sound  to  work  this  first,  though  like 
many  other  points  of  similar  nature  this  would 
be  governed  by  mining  conditions.  In  general, 
sound  business  principles  are  overridden  by 
engineers  oblivious  to  financial  economics 
who,  when  the  latter  are  discussed,  immedi- 
ately offer  some  technical  objection  whereby 
to  hide  ignorance.  The  measure  of  the  engi- 
neer is  his  ability  to  interpret  and  avoid  tech- 
nicalities, but  the  financial  world  is  too  often 
taken  in  or  silenced  by  a  technology  as  devious 
in  its  aim  as  the  dog  Latin  of  early  prelates. 

(c)  Another  mark  of  the  modern  school  is 
the  tendency  to  express  metal  contents  in 
monetary  units,  and  while  the  fluctuations  in 
value  may  not  be  avoided  any  more  than 
variations  in  working  cost  in  different  parts  of 
a  mine,  so  long  as  the  price  of  the  metals 
which  forms  the  basis  of  the  estimate  is 
given,  no  real  ambiguity  exists.  Surely  this 
were  simpler  for  an  investor  than  to  have  to 
calculate  for  himself  on  all  occasions  instead 
of  only  those  when  the  calculated  price  varies 
greatly  from  that  obtaining  later. 

{d)  The  second  article  of  the  series  dealt 
with  this  question  of  determination  of  reserves, 
but  Table  B  accompanying  Fig.  A  will  perhaps 
also  make  it  clear  to  anyone  familiar  with 
the  principle  of  deferred  annuities. 

(e)  What  is  urged  regarding  the  dearth  of 
detail  as  published  by  mining  companies  is  un- 
fortunately true,  especially  of  Cornwall.  In 
general  it  may  be  put  down  as  due  to  a  feeble 
effort  at  cunning,  iDut  occasionally  to  business 
ineptitude  or  moral  cowardice  on  the  part  of 
managers  and  engineers.  The  mining  inves- 
tor's remedy  lies  in  protest  at  the  annual 
meetings,  coupled  with  evidence  that  fuller 
details  are  published  by  other  companies.  In 
a  country  like  England,  where  civic  usually 
succeeds  financial  ambition,  few  directors  like 
to  be  held  up  as  an  example  of  those  who 
hide  facts  from  shareholders. 


(/)  With  regard  to  results  had  by  vanning 
or  chemical  analysis,  as  before  stated,  mining 
is  an  industry  and  as  such  its  results  should  be 
expressed  in  monetary  units.  For  the  investor 
the  gross  value  in  the  ore  and  the  costs  and 
losses  are  what  he  really  wants  to  know. 
Evidently  crude  operations  like  vanning,  how- 
ever useful  in  their  places,  give  no  true  record 
of  actual  content  either  in  heads  or  tails,  and 
yet  these  must  be  known  if  efficiency  is  to  be 
gauged. 

ig)  With  regard  to  Mr.  Fern's  impression 
that  the  value  of  small  mines  is  overlooked 
and  great  ones  only  to  be  ranked  as  invest- 
ments, it  may  be  as  well  to  emphasize  the 
fact  that  the  opposite  opinion  is  held.  If 
sufficient  reliable  data  can  be  obtained,  it  is 
hoped  to  show  that  many  small  mines  are  far 
sounder  financially  than  great  ones.  Though 
they  have  the  advantage  of  a  higher  class  of 
technical  advisers,  financiers,  and  engineers  to 
direct  them,  the  larger  concerns  usually  have 
a  greater  proportion  of  the  capital  represented 
by  'possibilities'  only.  It  is  the  writer's  be- 
lief that  the  tendency  or  desire  to  speculate  by 
investing  in  any  sort  of  enterprise  which  de- 
velops mineral  deposits  or  opens  new  country, 
has  its  roots  in  national  virility  as  surely  as 
the  trading,  fighting,  buccaneering  enterprises 
of  John  Company  days.  Share  speculation 
based  on  '  the  other  man's  "  credulity  is  quite 
another  matter  and  is  as  unsound  economically 
as  defective  from  a  civic  point  of  view.  The 
question  raised  concerning  the  degree  of  de- 
velopment necessary  before  ore  can  be  classed 
as  reserves,  is  the  very  basis  of  mining  finance 
and  should  the  second  article  not  have  made 
clear  the  contention  that  ore  opened  on  one 
side  only  may  also  be  so  classed,  I  shall  be  very " 
happy  to  elaborate  this  point  later.  As  will 
be  seen,  this  view  is  entirely  in  favour  of 
small  mines,  and  I  am  in  perfect  accord  with 
Mr.  Fern's  idea  that  any  propaganda  likely  to 
injure  the  latter  in  the  public  estimation  would 
be  a  great  pity  and  a  national  loss. 

M.    H.    BURNHAM. 

London,  June  27. 

Beginnings  of  Cyanidation. 

The  Editor : 

Sir — I  have  read  with  great  pleasure  Mr. 
McCombie's  article  on  this  subject,  and  con- 
gratulate him  on  presenting  your  readers  with 
a  clear  account  of  the  early  history  of  this 
important  industry.  As  far  as  I  can  judge, 
Mr.  McCombie  is  absolutely  accurate  in  all 
his  statements,  but  one.  He  reports  Mr. 
Dempster  as  among  the  dead.     I  am  happy 


JULY,    1911 


41 


to  inform  you  that  he  is  very  much  aHve. 
He  has  been  associated  with  me  since  the 
beginning  of  cyanidation,  and  is  still  busily 
engaged  in  erecting  cyanide  plants  all  over  the 
world,  and  in  doing  similar  work. 

In  order  that  there  may  be  no  mistake 
about  this  I  have  asked  Mr.  Dempster  to 
report  himself  to  you  at  the  first  opportunity. 
No  one  will  be  better  pleased  to  be  corrected 
in  this  matter  than  Mr.  McCombie  himself. 
John  S.  MacArthur. 

Glasgow,  June  21. 

Mexican  Unrest. 

The  Editor  : 

Sir — In  the  March  number  of  The  Mining 
Magazine  you  refer,  under  the  head  of  '  Mexi- 
can Unrest,'  to  the  subject  of  the  possibility 
in  the  future  of  the  annexation  by  the  United 
States  of  the  four  northern  States  of  Mexico. 
This  is  not  the  first  occasion  on  which  a  simi- 
lar utterance  has  come  under  my  notice. 

I  think  I  am  not  alone,  by  a  very  long  way, 
in  feeling  that  anything  tending  to  the  dis- 
integration or  re  -  partition  of  this  historic 
country,  at  length  arrived  at  a  position  of 
distinction  among  modern  nations,  is  to  be 
deprecated.  The  object  of  this  letter  is  not 
to  discuss  faults  of  internal  government  which 
have  led  to  the  recent  troubles,  nor  to  canvass 
the  political  situation,  but  merely  to  point  out 
that  by  reference  to  such  possibilities,  which 
in  your  article  you  also  would  seem  to  depre- 
cate, you  prepare  the  public  mind  to  accept 
them  even  as  probabilities.  What  we  are 
accustomed  to  hear  mentioned  is  apt  to  lose 
by  degrees  the  acuteness  of  the  first  shock  of 
surprise  and  we  become  prepared  for  what  we 
hope  will  not  happen. 

That  large  sums  of  capital  from  the  United 
States  of  North  America  are  invested  in 
Mexico  is,  of  course,  a  fact,  but  there  are 
also  large  sums  invested  by  other  nations, 
though  in  somewhat  less  degree.  To  say  that 
there  is  any  preparation  for  annexation  by 
the  importation  of  American  sentiment  is 
going  too  far.  The  Mexican  character  is 
perhaps  more  strongly  marked  in  the  north 
than  elsewhere,  as  evidenced  by  the  recent 
strenuous  and  effective  efforts  of  the  native 
population.  I  think  that  it  is  not  merely  an 
inborn  conservatism  or  sentimentality  on  my 
part  that  makes  me  hope  that  never  will  the 
area  of  this  great  country  be  further  encroached 
upon  or  diminished,  but  that  its  development 
will  be  assisted  by  an  even  greater  influx  of 
foreign  capital  than  heretofore.  The  mere 
suggestion  to  the  Mexican  mind  that  the  pres- 


ence of  foreigners  in  their  midst  has  for  its 
object  the  disintegration  of  their  country  can- 
not fail  to  destroy  the  friendly  relations  that 
are  so  necessary  for  the  development  of  enter- 
prises engineered  by  the  foreigner  ;  and  the 
sooner  and  the  more  completely  that  is  recog- 
nized by  the  world  at  large  the  better,  and 
then  we  shall  hear  no  more  of  the  '  annexa- 
tion' chimera. 

I  have,  Sir,  the  greatest  regard  for  your 
fairness  and  foresight  in  discussing  matters 
of  grave  importance,  but  I  am  wondering 
whether  in  your  recent  utterances  you  have 
considered  their  far-reaching  effect,  seeing  that 
your  magazine  enjoys  a  position  which  I  think 
I  may  say  without  flattery  is  unique  in  the 
world  of  mining. 

William  Crosley. 

Chihuahua,  May  10. 

Technical  Sensationalism. 

The  Editor  : 

Sir — At  the  last  meeting  of  the  Institution 
of  Mining  and  Metallurgy  the  remarks  made 
in  the  discussion  on  Mr.  Schmitt's  paper  were 
mostly  in  accord  with  those  made  by  your 
Johannesburg  correspondent.  It  was  felt  that 
Mr.  Schmitt's  assumption  of  the  lowering  of 
grade  in  depth  was  without  solid  foundation. 
As  indicated  by  one  speaker,  the  mere  study 
of  'returns  '  without  taking  into  account  all  the 
factors  tending  to  bring  about  a  lower  grade  is 
misleading.  One  such  factor,  as  wasmentioned, 
has  been  the  gradual  and  increasing  inclusion, 
from  the  early  days  up  to  the  present  time,  of 
large  blocks  of  ore  formerly  too  poor  to  be  pro- 
fitably mined  but  which  owing  to  reduced  costs 
have  gradually  fallen  within  the  limits  of  pay- 
ability. 

Another  speaker  mentioned  that  expansion 
had  taken  place  on  the  Rand,  not  only  in  depth, 
but  on  all  sides,  and  a  comparison  of  average 
ore-value  from  returns  of  deep-level  and  out- 
crop mines  might  possibly  destroy  the  impres- 
sion that  there  was  this  drop  in  grade.  The 
same  speaker,  referring  to  Mr.  Schmitt's  as- 
sumption that  mining  costs  would  increase 
with  depth,  remarked  that  although  power  con- 
sumption would  certainly  be  greater  yet  with 
the  advent  of  large  central  supply  stations 
they  might  actually  be  reduced. 

The  importance  of  the  question  of  mining 
costs  was  emphasized  in  another  contribution 
to  the  discussion,  in  which  it  was  put  forward 
that  no  field  offered  such  possibilities  for  re- 
ducing working  costs  as  that  underground. 
Reduction  in  this  respect  had  been  made  in  the 
past  and  it  was  reasonable  to  suppose  that  a 


42 


THE    MINING    MAGAZINE 


urther  and  greater  reduction  was  going  to  be 
made  in  the  future. 

Your  correspondentmentionsthe  inaccuracy 
of  some  figures  employed  in  calculating  the 
cost  of  sorting  (this  was  noticed  at  the  Insti- 
tution meeting),  and  he  goes  on  to  say  :  '  The 
cost  of  sorting,  it  should  not  be  necessary  to 
explain,  is  chiefly  governed  by  the  percentage 
of  rock  sorted  out,  not  by  the  percentage  looked 
at,  as  it  travels  along  a  belt."  I  feel  sure  this 
explanation  is  not  necessary,  as  Mr.  Schmitt, 
on  page  24  of  his  paper,  in  arrivmg  at  oper- 
ating costs  states  clearly  :  "  Sorting,  per  ton  of 
waste  discarded  .  .  .  Is.  Od.  It  seems  he  has 
confounded  the  figures  in  some  way  and  I  think 
your  correspondent  overlooks  this  in  his  endea- 
vour to  condemn  the  paper  in  a  wholesale  way. 

It  must  be  acknowledged  that  inaccuracy, 
especially  in  figures  that  have  so  important  a 
bearing  on  the  results  which  Mr.  Schmitt 
wishes  to  bring  out,  must  somewhat  discount 
the  value  of  the  paper.  In  Table  IV,  A  (16% 
basis),  seemingly  the  saving  in  operating  costs 
with  Mr.  Schmitt's  proposed  plants  should 
average  just  under  5d.  per  ton  hoisted,  as 
against  the  average  saving  of  just  under  8d. 
per  ton  hoisted  obtained  from  the  above  Table. 
In  Table  IV  (30%  basis),  however,  the  figures 
showing  the  saving  per  ton  hoisted,  due  to  his 
proposed  plants,  would  appear  to  be  slightly 
favourably  affected  by  amending  the  figures 
for  '  sorting.' 

No  doubt  many  of  Mr.  Schmitt's  assump- 
tions are  ill  founded,  as  has  been  suggested, 
but  it  has  yet  to  be  shown  that  a  saving  could 
not  be  effected  by  the  adoption  of  certain  of 
his  proposed  modifications  of  plant,  and  at 
any  rate  I  do  not  think  that  he  should  be  ac- 
cused of  a  lack  of  knowledge  of  the  conditions 
governing  the  cost  of  sorting. 

J.  C.  S.  Whittuck. 

London,  July  6,  1911. 


Freiberg.  —  A  preliminary  gathering  of 
old  Freibergers  was  held  at  the  Gambrinus 
restaurant  in  London  on  June  30,  the  following 
old  students  being  present  :  G.  Percy  Ash- 
more,  S.  H.  Blandy,  A.  G.  Charleton,  Harry 
J.  Donkin,  W.  R.  Feldtmann,  J.  A.  Hender- 
son, E.  Hooper,  L.  Kapps,  L.  Kessler,  C.  A. 
Mackenzie,  E.  P.  Rathbone,  H.  M.  Ridge, 
and  A.  R,  Sawyer.  It  was  unanimously  de- 
cided to  form  an  Association  to  be  called  '  The 
Old  Freibergers,'  which  would  hold  periodical 
dinners.  The  honorary  secretary  is  Edward 
Hooper,  of  3  London  Wall  Buildings.  Old 
Freibergers  are  requested  to  put  themselves 
in  touch  with  him  by  sending  their  addresses. 


PORCUPINE 

By   RALPH   A.    MEYER 

THE  market  at  the  moment  is  watching 
nothing  so  closely  as  the  extension  of  the 
railway  line  mto  Porcupine,  which  it  is 
now  pretty  well  assured  will  be  there  the  first 
of  July.  As  a  matter  of  fact  the  rails  are 
already  laid  within  one-quarter  of  a  mile  of 
South  Porcupine,  and  both  passengers  and 
freight  have  been  coming  in  all  the  way  from 
Kelso  as  far  as  Frederickhouse  by  means  of  an 
accommodation  train,  and  from  Frederickhouse 
to  Golden  City  (North  Porcupine)  by  means 
of  the  rail  and  ballast  trains.  It  is  not  to  be 
expected  that  this  itself  would  prove  a  factor 
of  any  importance  in  determining  the  trend  of 
prices,  or  even  in  influencing  to  the  slightest 
extent  the  sentiment  among  speculators.  It  is, 
however,  a  card  that  will  be  used  and  the  mar- 
ket is  not  averse  to  holding  such  a  card  at  this 
very  time.  The  coming  of  the  first  passenger 
train  into  the  district  will  ensure  a  big  influx 
of  mining  men.  Even  now  the  hotels  are 
crowded,  and  I  am  afraid  much  discomfort 
will  be  caused  by  inadequate  accommodation. 
The  completion  of  the  railway  will  hasten  the 
transfer  of  machinery  to  the  mines,  and  it  is 
only  to  be  expected  that  a  great  deal  of  activity 
of  the  right  kind  will  ensue.  The  recent  con- 
flagration tended  to  delay  such  a  result,  but  not 
for  long.  It  is  announced  that  several  com- 
panies, such  as  the  Hollinger,  have  already 
ordered  new  plants  to  replace  those  damaged 
by  the  bush  fires.  The  Hollinger  company 
has  decided  to  erect  a  mechanical  workshop  on 
a  large  scale  in  order  to  facilitate  repairs  to  the 
machinery  that  suffered  by  the  recent  fire. 
Meanwhile,  the  management  will  be  enabled 
to  push  intelligent  and  aggressive  prospecting 
on  the  surface. 

It  is  rumoured  that  the  Lewisohnshave  pur- 
chased the  Schumacher  veteran  claim,  consist- 
ing of  160  acres  in  Tisdale  township,  imme- 
diately south  of  Pearl  Lake  and  theTimmins 
property,  and  close  to  the  Hollinger.  Mr.  W. 
H.\\'eed, consulting  geologist  to  the  firm  men- 
tioned, has  recently  been  to  Porcupine,  and 
expressed  a  favourable  opinion.  He  states 
that  in  all  of  the  development  properties,  in 
addition  to  veins  carrying  spectacular  show- 
ings of  free-gold,  the  wall-rock  is  impregnated 
with  pyrite  carrying  gold  and  readily  amenable 
to  cyanide  treatment. 

The  work  of  the  Dome  Extension  is  attract- 
ing attention.  The  big  vein  discovered  a  month 
ago  has  been  uncovered.     It  is  36  ft.  wide, and 


JULY,    1911 


43 


running  parallel  with  it  are  four  lateral  veins, 
from  one  to  three  feet  wide.  Between  these 
lateral  veins  the  schist  pans  gold,and  the  whole 
orebody  is  over  50  ft.  wide.  The  main  vein  is 
composed  of  quartz,  which  is  good  mill-ore. 
Samples  across  the  vein  have  run  as  high  as 
$32  per  ton.  The  lateral  veins  are  rich,  show- 
ing visible  gold  in  many  places,  and  yield 
assays  running  into  hundreds  of  dollars. 

It  has  been  announced  in  London  and 
Torontothat  the  Bewick- Moreing  interest,  for- 
merly known  as  the  Northern  Ontario  Ex- 
ploration, has  issued  a  subsidiary  christened 
the  Ontario  Porcupine  Goldfields  Develop- 
ment Co.,  with  a  capital  of  /^600,000.  The 
holdings  of  the  said  company  comprise  50 
claims,  distributedoverthePorcupinearea, that 
formerly  belonged  to  the  Timmins-McMartin- 
Dunlap  syndicate.  The  new  company  takes 
entire  ownership  of  all  of  these  claims  and  has 
formed  a  strong  organization  to  carry  on  the 
work  of  development.  A  cash  fund  of  .'{^435,000 
has  been  raised,  and  this  with  $60,000  pro- 
vided by  the  former  owners  makes  a  working 
capital  of  about  $500,000  available  for  deve- 
lopment. The  advisory  board  in  Canada  is 
composed  of  Noah  Timmins,  Henry  Timmins, 
and  John  McMartin,  while  Bewick,  Moreing 
&  Co.  are  general  managers.  When  the  Tim- 
mins syndicate  acquired  the  HoUinger  mine 
and  found  a  bonanza,  they  proceeded  to  acquire 
claims  in  the  vicinity  of  the  Hollinger  and  in 
other  parts  of  the  goldfield.  Last  year  the  firm 
of  Bewick,  Moreing  &  Co.  sent  representatives 
to  make  an  examination  of  Porcupine,  and  be- 
coming desirous  of  acquiring  property,  they 
negotiated  with  the  syndicate  for  a  one-half 
interest  in  50  of  its  claims.  Hence  the  On- 
tario Porcupine  Goldfields  Development  Co. 
Supplies  and  machinery  were  brought  in  over 
the  winter  roads  and  two  large  camps  were  es- 
tablished, one  on  the  Dunlap  claim  of  the 
Aitchison  group,  and  one  on  the  Miller  claim 
near  the  Hollinger.  In  both  places  operations 
are  now  proceeding  actively.  The  camp  on 
the  Miller  claim  is  the  headquarters,  from 
which  work  is  now  being  directed  on  the  Shan- 
non claims,  north  of  Gillies  lake.  The  field 
management  has  been  placed  in  charge  of 
Gerald  Lovell,  assisted  by  Ernest  Williams. 
In  addition  Malcolm  Maclaren  is  expected 
from  Australia,  to  make  a  thorough  geological 
examination  of  the  goldfield. 

It  is  rumoured  that  the  Porcupine  Gold 
Mines,  controlling  the  Vipond,  may  receive  at 
least  $200,000  for  part  of  this  company's  hold- 
ings in  Tisdale.  This  is  the  only  property  in 
Porcupine  that  has  shipped  any  gold  bars,  and 


is  still  continuing  to  do  so.  Three  weeks  ago 
the  sixth  bar  of  gold  was  sent  out,  of  a  value 
of  $2000.  The  west  drift  on  the  100-ft.  level 
of  the  No.  2  vein  has  cut  the  long  ore-shoot 
which  has  been  stripped  on  the  surface  for 
several  hundred  feet.  The  cross-cut  south  of 
the  100-ft.  level  to  cut  the  No.  3  vein,  which 
on  the  surface  is  wider  and  richer  than  the  No. 
2,  has  been  driven  50  ft.  and  will  probably 
reach  ore  within  three  weeks.  A  larger  mill 
will  shortly  be  erected;  up  to  the  present  time 
two  Nissen  stamps  have  been  in  use. 

The  West  Dome  has  got  up  steam,  and 
will  begin  drilling  on  another  part  of  the  40- 
acre  lot  on  which  work  is  now  being  done. 
This  will  make  three  shot-drills  in  operation. 
The  third  drill  will  be  set  up  at  an  angle,  so 
as  to  hit  the  vein  at  a  depth  of  1000  ft.  The 
shaft,  which  is  on  the  vein,  is  now  down  70ft., 
and  is  progressing  rapidly  by  aid  of  two  air- 
drills. 

A  London  syndicate,  headed  by  W.  Laing 
Malcolmson,  has  acquired  the  property  known 
as  the  Success.  H.  Brian  Pearson,  likewise 
of  London,  is  consulting  engineer,  and  Ralph 
A.  Mayer  has  been  appointed  manager.  The 
property  comprises  160  acres,  bounded  on  the 
west  by  the  Crown  Chartered  and  Vipond,  on 
the  north  by  the  Ontario  Porcupine  Goldfields 
Development  Co.,  on  the  east  by  the  Dobie, 
and  on  the  south  by  the  Dobie  and  Watson 
Syndicate.  Numerous  large  quartz  orebodies 
have  been  found  and  the  management  has 
commenced  active  prospecting  and  sampling. 

The  directors  of  the  Porcupine  Power  Co. 
have  decided  to  increase  their  hydro-electric 
installation  at  Sandy  Falls  by  an  additional 
2000  hp.  The  original  plant,  producing 
3000  hp.,  was  about  finished,  and  from  the 
progress  of  the  camp  in  general  it  was  decided 
to  increase  the  capacity  as  stated. 

The  latest  rush  in  the  Porcupine  area  was 
made  this  last  week  to  Bristol  township,  in 
the  Cripple  Creek  section,  where  wonderful 
showings  have  been  discovered  on  the  Mc- 
Cauley  claims.  Cripple  Creek  has  been  be- 
fore the  eyes  of  the  public  for  some  time 
and,  although,  taking  that  country  as  a  whole, 
free  gold  showings  have  not  been  as  exten- 
sive as  in  the  real  Porcupine  area,  assays 
have  been  much  more  uniform. 

Another  interesting  locality  is  the  Swastika 
district,  in  the  township  of  Otto  and  midway 
between  Cobalt  and  Porcupine. 

The  scourge  of  mosquitos  is  particularly 
bad  this  year,  but  they  are  now  at  their  worst, 
and  in  another  three  weeks  it  will  again  be 
possible  to  enjoy  a  day's  work   in  the  bush. 


44 


THE    MINING    MAGAZINE 


PERSONAL 

R.  S.  BoTSFORD  has  returned  from  Brazil. 

S.  E.  Bretherton  has  been  appointed 
consulting  engineer  to  the  Adaven  Mining 
&  Smelting  Co.  in  Nevada. 

Walter  L.  Brown  has  been  appointed 
manager  of  the  Abbontiakoon  mine  in  West 
Africa. 

J.  Morrow  Campbell  is  on  his  way  to 
Tanganyika. 

M.  H.  CooMBE  has  been  appointed  manager 
for  the  Government  Gold  Mining  Areas,  Mod- 
derfontein, 

Frank  L.  Cole  and  Russell  Y.  Han- 
LON  announce  that  they  have  formed  a  part- 
nership as  consulting  mining  engineers,  with 
offices  at  Manila,  Philippine  Islands. 

J.  H.  Curle  sailed  for  New  York  on 
June  30. 

Arthur  Dickinson  left  England  on  June 
17  for  Norway. 

H.  Swan  Edgar  has  been  appointed  resi- 
dent manager  of  the  Carn  Brea  &  Tincroft 
mines,  Cornwall. 

Maitland  Edwards  is  in  Turkey. 

W.  R.  Feldtmann  has  taken  into  part- 
nership James  A.  Mactear  and  H.  L. 
Sargent.  The  style  of  the  new  firm  will  be 
W.  R.  Feldtmann  &  Co. 

William  Frecheville  is  back  from  the 
Transvaal. 

William  Hope  Henderson  sailed  on 
July  5  for  the  United  States. 

C.  S.  Herzig,  who  is  making  a  tour  in 
South  America,  writes  from  Manaos,  Brazil. 

Bernard  W.  Holman  is  at  Johannesburg. 

E.  Homersham  is  now  manager  of  the 
Prestea  Block  A  mine. 

J.  Power  Hutchins  has  returned  from 
the  Ural. 

Arthur  Jarman,  of  the  Auckland  School 
of  Mines,  N.Z.,  has  been  appointed  assistant 
superintendent  of  the  Waihi  Grand  Junction, 

Ronald  Johnstone  Jr.  has  gone  to  Aus- 
tralia for  the  British  Australian  Oil  Company. 

Courtenay  De  Kalb  was  in  Arizona 
during  June. 

P.  Kirkegaard  is  manager  of  the  North 
Dome  mine  at  Porcupine. 

William  Knox  has  sailed  from  San  Fran- 
cisco for  Vladivostok. 

G.  W.  Macfarlane  has  returned  from  the 
Gold  Coast. 

H.  F.  Marriott  has  gone  to  Porcupine. 


Ralph  A.  Meyer  has  been  appointed 
manager  of  the  Success  mine  at  Porcupine. 

C.  Algernon  Moreing  and  W.  J. 
Loring  sailed  on  July  8  on  their  way  to 
Porcupine. 

Percy  G.  Morgan  succeeds  J.  M.  Bell 
as  director  of  the  New  Zealand  Geological 
Survey. 

F.  L.  Morris  is  at  Dawson. 

Frank  J.  Murphy,  formerly  at  Bingham, 
is  now  superintendent  of  the  Great  Cobar 
smelter. 

B.  H.  Nicholson,  manager  for  the  Ray- 
field  Syndicate,  has  returned  from  Northern 
Nigeria. 

F.  Douglas  Osborne  has  left  for  South 
Africa  to  examine  a  tin  placer. 

J.  C.  Pickering  is  at  Porcupine  in  the 
interest  of  the  Exploration  Company. 

A.  J.  Pollack,  of  San  Francisco,  spent  a 
few  days  in  London. 

C.  W.  Purington  is  at  St.  Petersburg. 
James  Roberts  is  in  the  Argentine. 

L.  D.  Ricketts  has  been  appointed  con- 
sulting engineer  to  the  Arizona  Copper  Co. 
of  Edinburgh,  and  will  prepare  plans  for  the 
re-organization  of  the  reduction  plant. 

H.  N.  Schnurmann  has  gone  to  the 
Hazaribagh  district,  Bengal,  for  a  year. 

S.  F.  Shaw  was  recently  at  Porcupine. 

Thos.  B.  Stearns,  of  Denver,  is  in  Lon- 
don, on  a  vacation. 

Ralph  Stokes  is  expected  in  London 
from  Johannesburg. 

W.  F.  A.  Thomae  is  expected  shortly  on 
his  return  from  Siam. 

Scott  Turner  did  not  return  to  America  ; 
he  is  now  in  Spitzbergen. 

Claude  Vautin  has  returned  from  South 
America. 

H.  Vincent  Wallace  is  acting  as  man- 
ager for  the  Mineral  Development  Co.  at 
Guanajuato. 

E.  M.  Weston  has  resigned  as  lecturer  on 
mining  at  the  South  African  School  of  Mines 
and  has  left  for  Rhodesia,  where  he  will  act 
as  engineer  to  the  Barnato  group. 

Richard  E.  Williams  and  James  A. 
Thomson,  both  of  the  Waihi  mine,  are  in 
London. 

Lewis  T.Wright  has  resigned  as  manager 
for  the  Mountain  Copper  Co.  in  California. 

Old  Students  of  the  Royal  School  of 
Mines  are  urged  to  send  their  addresses  to 
Arthur  C.  Claudet,  6  Coleman  St.,  London. 


RECENT   PROGRESS  AT  MAIKOP 

By  THEODORE.  J.   HOOVER 


THE  development  of  the  Maikop  oilfield 
during  the  first  half  of  1911  has  been 
marked  by  three  significant  events.  First, 
the  opening  of  two  fountain  wells  (on  Plot  489) 
which  flowed  at  the  rate  of  500,000  poods  per 
day  before  being'capped  ;  second,  the  opening 
of  another  strong  fountain  well  on  Plot  490  ; 
and  third,  the  completion  of  the  pipe-line 
from  the  oilfield  to  the  Vladikafkas  railway 
at  Ekaterinodar.  This  pipe-line  opens  up  a 
limited  market  for  fuel -oil  and  refined  products 
on  the  railway  and  contiguous  territory,  and 
while  this  market  is  restricted  in  area  it  will 
consume  a  constantly  increasing  amount,  suffi- 
cient in  all  likelihood  to  pay  a  profit  on  the 
investment.  The  cost  of  the  railway  haulage 
on  oil  from  Ekaterinodar  to  the  seaboard  at 
Novorossisk  will  probably  be  prohibitive  of 
any  large  traffic  in  this  direction  and  the  real 
outlet  to  the  Maikop  district  will  be  by  pipe- 
line to  Touapse. 

The  Maikop  Mutual  Oil  Transport  Co.  is 
constructing  a  line  to  the  port  of  Touapse  ;  this 
will  be  operating  before  the  end  of  the  year. 
Already  three  other  lines  are  projected,  for 
one  of  which  the  pipes  have  been  ordered. 
The  port  of  Touapse  affords  a  safe  anchorage 
with  28  ft.  of  water  at  the  entrance.  Further 
harbour  improvements  are  progressing  rapidly, 
ensuring  a  large  dock-area  and  deeper  water 
at  the  entrance.  The  Touapse  pipe-lines  will 
follow  closely  the  line  of  the  Armivir-Touapse 
railway  for  most  of  the  way  down  the  valley 
of  the  Touapse  river.  The  engineering  diffi- 
culties of  building  this  pipe-line  are  consider- 
able, though  not  insuperable,  as  was  confi- 
dently stated  in  many  quarters  a  year  ago. 
The  pumping  stations,  working  directly  from 
the  field,  will  have  to  work  against  a  pressure 
of  about  950  lb.  per  square  inch  ;  the  chief 
engineering  difficulties  are  those  occasioned 
by  the  crowding  of  a  railway,  a  military  road, 
a  rapid  river,  and  the  pipe  lines  into  the 
narrow  confines  of  a  mountain  valley. 

Drilling  results  in  the  district  for  the  first 
six  months  of  the  year  are  inconclusive.  More 
than  50  power  rigs  are  at  work  on  wells  aver- 
aging roughly  from  100  to  1000  ft.  deep. 
These  wells  should  all  be  put  down  to  depths 
of  from  1000  to  2000  ft.  The  four  wells  of 
the  Black  Sea  Oil  Fields  on  Plot  490  are  all 
producing  regularly,  the  well  of  the  Maikop 


Victory  on  Plot  489  is  producing  50,000  poods 
per  day,  and  the  Maikop  Spies  has  sold  some 
oil  from  the  well  on  Plot  533. 

The  oil  from  all  of  these  wells  was  sent  to 
market  by  the  Maikop  Pipe-line  Co.  at  Eka- 
terinodar. The  well  of  the  Maikop  Oil  & 
Petroleum  Producers  is  yielding  12,000  poods 
per  day  regularly  and  the  oil  is  being  stored 
pending  connection  with  a  pipe-line  and  mar- 
ket. This  company  now  has  over  a  million 
poods  of  oil  stored  on  the  surface.  The 
London  and  Maikop  Oil  Corporation  well  on 
Plot  411,  while  producing  some  oil  whenever 
occasion  requires,  is  hampered  by  a  lack  of 
storage  and  transport  facilities.  The  Govern- 
ment has  also  been  very  slow  in  arranging  for 
the  measurement  of  oil  on  this  plot,  and  until 
these  arrangements  are  made  no  regular  pro- 
duction can  take  place.  This  well  is  the 
most  encouraging  development  on  the  Maikop 
field  since  the  start,  as  it  is  at  such  a  distance 
from  the  original  discovery  on  plot  490  of  the 
Maikop  Oil  &  Petroleum  Producers,  and  at 
such  greater  depth  that  it  probably  indicates 
the  existence  of  at  least  one  other  productive 
pool  besides  that  tapped  by  the  first  well. 
The  Maikop  Apsheron  Oil  Co.  and  the  Maikop 
Areas  are  both  drilling  wells  near  Plot  411, 
and  should  strike  the  same  formation  at  about 
the  same  depth  as  the  well  on  411,  that  is, 
850  ft.  At  the  Hadijensky  end  of  the  field, 
oil  has  been  struck  in  paying  quantities  on 
Plots  51,  59,  and  110,  but  the  wells  have  not 
been  flowing.  The  Maikop  Premier  found 
oil  on  Plot  488  at  1385  ft.  but  the  quantity  is 
not  known. 

Anyone  standing  on  the  hills  overlooking 
the  Fountain  valley  is  strongly  impressed  with 
the  visible  manifestations  of  an  oil  boom. 
There  is  growing  up  under  one's  eyes  an  oil 
city,  and  at  such  a  speed  that  it  can  be  seen 
growing.  On  the  Plots  592,  572,  573,  553, 
554,  533,  534,  513,  512,  and  490,  all  of  which 
are  either  crossed  by  the  river  Chakoh  or  are 
on  the  flanks  of  the  valley  of  that  stream  and 
all  within  the  linear  extent  of  less  than  two 
miles,  the  following  active  companies  are  op- 
erating, in  regular  order  beginning  at  the  east 
end  :  The  central  administration  of  the  Maikop 
&  General  Petroleum  Trust  group  in  new 
quarters  recently  completed,  comprising  office, 
manager's  house,  staff  quarters,  machine-shop. 


45 


46 


THE    MINING    MAGAZINE 


stores,  and  an  independent  provision  and  cloth- 
ing store  and  restaurant.    The  companies  that 
have  headquarters  here  are  the  Maikop  Areas, 
the    Maikop   Apsheron  Oil  Co.,  the  Maikop 
Hadijensky   Syndicate,  and  the  parent  com- 
pany,   the    Maikop  and  General   Petroleum 
Trust.     A  few  hundred  yards  up  the  valley 
and  chaussee  road  to  the  west,  is  the  head- 
quarters   and    main    pumping-station    of   the 
Maikop   Mutual   Oil  Transport  Co.  on   Plot 
573,  whence  the  pipe-line  of  that  company 
starts    through    Hadijensky    to    Touapse,    at 
which  latter  point  are  the  main  offices  of  this 
company.     The  erection  of  storage  reservoirs, 
buildings,  and    the   necessary    machinery   on 
Plot  573  is  being  rapidly  pushed  toward  com- 
pletion.    A  quarter  of  a  mile  farther  up  the 
road    and   valley   is    the   auxiliary   pumping- 
station  of  the  Maikop  Pipe-line  &  Transport 
Co.,  the  main  pumping-station  of  this  com- 
pany being  near  Hadijensky,  12  miles  away. 
Here  also  are  three  large  reservoirs.      Just 
across  the  creek  are  the  offices   and    head- 
quarters   of   the    Maikop    Oil    &    Petroleum 
Producers  on  Plot  53  with  staff  quarters  and 
three  large  reservoirs  holding  900,000  poods 
of  oil.     Next  come  various  small  independent 
shops  and  bakeries,  and  then  on  Plot  533  the 
offices  and  headquarters  of  the  Maikop  Spies 
Co.  with  staff  quarters.     Next  in  order  is  the 
storage  plant  of  the  Anglo- Maikop  Corpora- 
tion on  Plot  513,  where  there  is  a  small  oil- 
pumpmg  plant.     Then  follows  the  scene  of 
activity  in  the  vicinity  of  Plot  490,  where  the 
activities    of  the    Maikop    Oil    &   Petroleum 
Producers,  the  Black  Sea  Oilfields,  Maikop 
Enem,  British  Maikop  Co.,  and  others,  com- 
plete the  west  end  of  an  active  mile  and  a 
half.      All  these   newly   built  structures   are 
interspersed  with  derricks,  small  houses,  and 
barracks ;  the  road  is  crowded  with  hundreds 
of  teams  of  horses  and  oxen  loaded  with  pipe, 
casing,  machinery  of  all  sorts,  and  provisions. 
The  audible  evidence  of  activity  is  a  babel  of 
tongues   in   which   Russian  is  dominant,  but 
German,  French,  Polish,  Turkish,  Greek,  Ar- 
menian,   and    a    dozen    explosive    Caucasian 
tongues  contribute  their   share ;    incidentally 
it  may  be  remarked  that  English  of  a  violent 
character  appears  to  be  frequent  in  the   vi- 
cinity of  the  many  mud-holes.     A  lusty  young 
town  is  beginning  here  !   it  is  now  frequently 
designated  as  the  town  of  Saltykoffsky,  named 
in  honour  of  Prince  I.   N.  Saltykoff,  who  in 
the  early    days  was,  and   still   is,   a  moving 
spirit  in  the  development  of  the  oilfield.    There 
should  be  a  post  and  telegraph  office  at  this 
place,  because  more  than  half  the  business  of 


the  Maikop  district  is  transacted  on  or  near 
this  spot,  but  owing  to  the  procrastination  of 
those  who  have  these  things  in  hand  in  Rus- 
sia, it  will  probably  be  some  time  before  such 
necessary  facilities  are  provided. 

Police  arrangements  in  the  district  are  con- 
spicuous by  their  absence.  A  highly  enter- 
taining chapter  could  be  written  on  this  sub- 
ject, with  brigands  in  the  foreground  and 
inert  officials  in  the  background  (very  far 
back),  but  it  is  perhaps  just  as  well  not  to 
dwell  on  this  feature.  It  should  be  said, 
however,  that  the  English  companies  opera- 
ting at  Maikop  owe  thanks  to  their  staffs, 
over  and  above  mere  salaries,  for  the  loyal 
manner  m  which  they  have  stuck  to  their 
posts  in  the  face  of  trying  circumstances. 
Within  the  last  three  weeks  the  police  of  the 
district  have  for  the  first  time  displayed  suffi- 
cient activity  to  arrest  anyone.  After  a  par- 
ticularly bad  instance  of  highway  robbery, 
they  threw  a  cordon  around  the  district  and 
stopped  everyone  for  an  inspection  of  pass- 
ports. As  this  was  an  unusual  move  the  re- 
sult was  that  a  large  number  of  innocent  peo- 
ple were  detained  because  they  had  left  their 
passports  at  home. 

The  Armivir-Touapse  railway  will  without 
doubt  be  completed  to  Hadijensky  this  sum- 
mer. Hadijensky  lies  almost  at  the  extreme 
northern  end  of  what  is  now  considered  the 
Maikop  district.  There  will  also  be  built  at 
least  one  electric  line  traversing  the  whole 
district  longitudinally  and  connecting  with 
this  railway  at  Hadijensky.  The  influence 
of  railway  connection  on  the  development  of 
the  oilfield  will  be  of  the  utmost  importance, 
and  conversely  the  oilfield  will  make  the  rail- 
way. The  railway  will  give  outlets  for  oil  and 
access  to  markets  in  the  productive  grain- 
growing  country  of  Maikop  and  Armivir. 

In  general  it  may  be  said  with  candour 
that  the  prospects  of  the  field  are  good  in 
view  of  only  eighteen  months  development, 
but  investors  will  of  necessity  have  to  curb 
their  impatience  for  results.  The  present 
drilling  results  are  rapidly  placing  in  the  hands 
of  engineers  data  which  will  enable  more 
intelligent  direction  of  the  work  than  was 
possible  at  the  inspection.  Fully  fifty  drill- 
ing equipments  will  be  at  work  during  the 
ensuing  six  months.  Two  productive  areas 
are  known,  and  the  fortunate  companies  own- 
ing land  in  or  near  these  areas  should  pay 
dividends  within  two  years.  The  question 
whether  oil  exists  outside  of  the  two  territories 
can  only  be  answered  when  the  present  drill- 
ing campaign  is  further  advanced. 


THE  REFORMA   MINE 


By  C.  S.  THOMAS,  Jr. 


DURING  the  last  ten  years  Mexico  has 
been  much  in  the  hme-hght  of  the  min- 
ing stage.  The  EngUsh,  who,  in  the  last 
few  decades,  have  been  the  leading  spirits  in 
the  exploitation  of  the  precious  metal  mining 
districts,  have  invaded  Mexico  systematically 
and  carefully  and  thereby  have  reaped  a  rich 


CAMPO  MOBADO,   MEXICO. 

reward.  Americans,  intent  on  and  occupied 
with  the  exploitation  of  their  own  almost  illi- 
mitable resources — including  a  greedy  and 
credulous  public — did  not  spread  out  much 
prior  to  1900.  Since  then  their  mineral  re- 
sources have  undergone  limitationand  the  pub- 
lic having  become  better  educated,  they,  too, 
have  invaded  Mexico,  and,  to  a  smaller  degree, 
Canada,  until  now  the  combined  investments 
of  British  and  American  capital  in  Mexico 
amount  to  nearly  two  thousand  million  dollars. 
Mexico  is  attracting  attention  at  the  present 
time  because  of  a  desultory  revolution.  The 
iron  hand  of  Diaz  seems  to  have  lost  its  grasp, 


although  incipient  rebellions  in  the  southern 
parts  of  the  country  are  crushed  suddenly  and 
without  mercy.  Lively  interest  in  this  unrest 
is  occasioned  by  the  fact  that  any  serious  de- 
predations might  require  British  or  American 
interference  in  order  to  protect  the  property 
and  lives  of  foreigners. 

In  America  copper 
is  dominant  now.  For 
the  last  three  or  four 
years,  in  the  face  of  a 
production  increasing 
faster  than  consump- 
tion, we  have  witnessed 
the  development  and 
exploitation  of  the  so- 
called  ' porphyry '  cop- 
per mines :  the  Utah 
Copper,  Nevada  Con- 
solidated, Ray  Consoli- 
dated, Miami,  Inspira- 
tion, and  Chino.  The 
reserves  of  these  pro- 
perties, variously  esti- 
mated at  from  400  to 
500  millions  of  tons, are 
not  so  great  when  one 
considers  the  huge  ton- 
nage that  must  be  min- 
ed to  make  them  proht- 
able.  We  may  expect 
to  see  them  exhausted 
in  about  25  years  un- 
less still  more  ore  is  de- 
veloped. In  addition, 
there  are  possibilities 
that  some  of  them, 
while  successful,  may 
not  come  up  to  expectations  in  the  matter 
of  the  costs  of  exploitation.  With  a  few 
exceptions  all  the  mining  is  underground 
work  on  flat  deposits,  and  it  is  likely  that  even 
now  the  best  ore  is  being  extracted.  I  await 
with  hope,  but  with  some  misgiving,  the  out- 
come of  the  future  low  costs  in  these  opera- 
tions. The  Butte  mines,  the  old  camps  of 
Arizona,  and  the  Michigan  copper  belt  will  not 
be  highly  productive  after  the  next  25  years. 
Therefore  we  must  look  to  the  less  exploited 
countries,  such  as  Africa,  Russia,  South 
America,  Mexico,  and  Alaska  for  our  future 
copper  supplies. 


47 


48 


THE    MINING    MAGAZINE 


The  Re  forma  mine  and  the  district  of  Campo 
Morado  in  which  it  is  situated  are  Hkely  to  prove 
an  important  source  of  copper,  together  with 
considerable  precious  metal.  This  mine  is  in 
Guerrero,  Mexico,  a  region  wild  and  little  ex- 
ploited, and  about  which  little  has  been  written. 
Copper  has  been  known  to  exist  in  this  State 
for  many  years.  The  old  General,  after  whom 
the  State  was  named,  at  the  close  of  the  war 
following  Mexico's  revolt  from  the  rule  of 
Spain,  paid  his  soldiers  with  copper  pesos,  the 
metal  in  them  dug  from  the  ground  near  Campo 
Morado,  smelted  crudely  and  hammered  out 
with  the  words  "8  Reales"  stamped  upon  them. 

Campo  Morado  is  at  present  inaccessible  so 
far  as  its  low-grade  ores  are  concerned  and  the 
owners  are  principally  occupied  in  mming  the 
high-grade  oxidized  ore,  which,  in  spite  of  the 
distance  of  the  property  from  railway  transpor- 
tation, yields  a  handsome  profit.  The  mine  it- 
self is  about  50  miles  (80  kilometres)  northwest 
of  Balsas,  the  present  terminus  of  the  Mexican 
Central  railroad  in  Guerrero.  It  is  a  rough 
country,  wild,  and  very  sparsely  inhabited. 
The  bulk  of  the  population  is  scattered  in 
small  villages  and  consists  mostly  of  Indians. 
The  mine  is  reached  by  rail  from  Mexico  City 
as  far  as  Balsas  ;  the  remaining  80  kilometres 
may  be  traversed  by  floating  down  the  Balsas 
river  in  barges  to  the  station  of  the  Reforma 
Mining  Co.  at  Pezoapan.  Thence  it  is  a  30 
kilometre  ride  on  horseback  to  the  mine. 

The  Balsas  river  is  one  of  the  large  streams 
of  Mexico,  for  even  in  the  dry  season  it  boasts 
a  large  flow  of  water.  At  the  time  of  my  trip 
the  rainy  season  was  just  beginning  and  the 
water  was  high  and  running  swiftly.  The 
river  has  its  source  in  the  mountains  of  Puebla 
and  Oaxaca  and  evidently  it  serves  as  a  power- 
ful agent  of  erosion.  During  the  rainy  season 
the  water  contains  about  15%  of  sand  and  silt. 
The  prevailing  rocks  of  the  watershed  are  so 
soft  as  to  cause  great  difficulty  in  the  proper 
maintenance  of  power  sites.  There  are  an 
average  of  about  two  rapids  per  mile.  The 
drop  in  elevation  from  Balsas  to  Pezoapan  is 
from  500  metres  to  460  metres  in  a  distance 
of  80  kilometres. 

The  return  trip  is  made  on  horseback.  The 
general  country  is  steep,  but  not  rugged.  Al- 
though the  slopes  of  the  mountains  are  smooth 
and  well  covered  with  the  products  of  erosion 
the  vegetation  is  comparatively  scant.  Timber 
large  enough  for  mine  use  is  scarce. 

The  prevailing  rocks  are  shale,  slate,  and 
limestone,  of  the  Lower  Cretaceous.  These 
beds  are  seen  in  the  canyon  of  the  Balsas 
almost  always  dipping  steeply,  giving  evidence 


of  extraordinary  and  probably  profound  move- 
ment. Occasional  intrusive  bodies,  generally 
sills  between  the  sedimentaries,  appear.  On 
the  road  from  Pezoapan  to  Campo  Morado  a 
large  dike  of  a  coarse  grained  porphyry  was 
observed  crossing  the  strata  for  several  miles. 

At  the  Reforma  a  large  body  of  grano-diorite 
has  intruded  itself  and  forms  the  hanging  wall 
of  the  vein,  which  cuts  across  a  mountain  with 
very  steep  sides  and  a  sharp  ridge.  It  is  de- 
veloped by  SIX  tunnelsrunning  entirely  through 
the  mountain  and  driven  in  the  foot-wall  of  the 
vein.  Frequent  cross-cuts  expose  a  width  of 
lode  averaging  100  feet.  The  lowest  tunnel, 
some  700  ft.  below  the  top  of  the  pyrite  ore- 
body,  shows  a  length  of  about  2000  ft.  of  solid 
pyrite.  The  oxidized  ores  follow  the  profile  of 
the  hill  along  the  top  of  the  pyrite  and  have  an 
average  depth  of  200  to  300  ft.  The  transition 
from  completely  oxidized  ore  to  sulphide  is 
most  abrupt.  This  is  due  to  the  even  grade 
of  the  ore  and  its  uniform  texture.  In  the 
process  of  oxidation  the  metallic  contents  were 
leached  and  deposited  on  the  foot-wall  side  of 
the  vein,  against  the  top  of  the  pyrite  orebody. 
The  residuumthencrumbledandformeda  layer 
of  low-grade  sand.  The  volume  of  space  occu- 
pied by  the  vein  was  considerably  decreased 
after  oxidation  and  the  hanging  wall  collapsed, 
forming  a  layer  of  loose  rock  and  dirt  over  the 
sand.  Such  a  condition  makes  the  ground 
heavy  and  requires  careful  work  to  prevent 
caving.  Only  the  oxidized  ore  is  being  mined 
at  present  ;  it  will  average  about  25  to  30% 
FesOs,  25  to  30%  SiOo,  8  to  15%  Pb,  besides 
gold  and  silver.  The  ordinary  run  of  ore  has 
an  assay- value  of  from  ,S50  to  $100  per  ton. 

The  pyrite  orebody  is  immense  and,  of 
course,  constitutes  the  bulk  of  the  ore  in  the 
mine.  It  is  practically  a  solid  mass  of  sulphide 
containing  small  quantities  of  copper,  zinc,  and 
lead,  with  a  little  gold  and  silver.  It  is  a  little 
richer  in  copper  on  the  foot-wall  side  for  a 
width  of  about  20  ft.  than  on  the  hanging-wall 
side.  The  grano-diorite  of  the  hanging- wall 
was  evidently  the  medium  through  which  the 
original  fissure  was  made.  This  fissure  was 
probably  wide,  100  to  150  ft.,  and  involved  a 
complete  shattering  of  the  slate  for  the  entire 
width  of  the  fissured  zone.  The  vein  is  a  re- 
placement deposit  in  a  wide  fissured  zone. 
This  is  evident  from  the  regularity  of  the 
walls.  The  slate  is  somewhat  carbonaceous, 
thus  affording  an  excellent  precipitant  for  the 
metals  in  the  thermal  solutions. 

The  assay-value  of  the  pyrite,  with  the  ex- 
ception of  the  slightly  richer  foot- wall  streak, 
is  most  regular.    Samples  for  10  feet  and  from 


JULY,    1911 


49 


THE   RKFURMA   SMKLTER. 


HAULING   WATEB-JACKETS  TO   THE  FUIiNACES. 


50 


THE    MINING    MAGAZINE 


125  to  150  pounds  each,  often  do  not  show  a 
variation  in  value  of  more  than  5  to  10%. 
There  are  developed  above  the  sixth  level  a 
little  over  9,000,000  tons  of  pyrite  ore  contain- 
ing 4  oz.  silver,  0'08  oz.  gold,  and  1*52%  cop- 
per per  ton  This  ore  carries  an  average  of 
38%  iron  and  42%  sulphur,  it  is  practically  solid 
pyrite. 

In  addition  to  the  main  Reforma  lode  there 
is  another  parallel  vein,  smaller  but  similar  in 
character.  Thus  far  the  ore  in  this  vein, 
known  as  El  Naranjo,  has  only  been  developed 
on  the  west  side  of  the  hill.  The  main  pyrite 
erebody  in  the  Naranjo  has  been  developed  on 
three  levels.  Samples  taken  on  the  two  upper 
levels  averaged  respectively  2'75  oz.  silver, 
0*34  oz.gold,  4'7%  copper,  and  14"50  oz.  silver, 
0T08  oz.  gold,  1*58%  copper. 

Besides  these  two  orebodies,  the  Reforma 
and  the  Naranjo,  there  has  been  opened  up, 
in  a  cross-cut  from  the  Reforma,  another 
known  as  the  Mamey.  It  is  only  cut  in  one 
place,  however,  so  that  little  is  known  about 
it  as  yet. 

The  oxidized  ore  is  mined  by  a  sort  of 
gopheringcavingsystem.  The  openings  under- 
ground are  kept  as  small  as  is  consistent  with 
getting  the  ore  out.  About  60  tons  per  day  is 
mined  and  treated  in  a  smelter  having  two  36 
by  60in.-  water-jacketed  blast-furnaces  and 
three  4  by  5  ft.  English  cupelling  furnaces. 
Some  of  the  lead  bullion,  that  running  over 

Reforma. 

Lead Tr.  Tr.  Tr. 

Copper 1-5  265  ISS 

Iron 3480  3980  3820 

Lime 060  Tr.  60 

Insoluble 1650  700  1200 

Sulphur  3480  4410  3950 

Zinc  380  3  30  370 

Arsenic  —  —  — 

Silver  oz 411  5.19  4  97 

Gold,  oz 008  009  008 

2%  in  precious  metals,  is  cupelled  and  the  gold 
and  silver  extracted.  The  lower  grade  bullion 
is  packed  on  mules,  two  bars  to  an  animal. 

All  supplies  are  brought  by  rail  to  Balsas, 
where  they  are  transhipped  to  barges  made  of 
native  timber.  These  barges  have  a  capacity 
of  four  tons  each.  They  are  manned  by  a 
•crew  of  four  natives,  who  steer  them  as  they 
float  down  the  river  and  drag  them  back  on  the 
return  trip.  The  trip  down  requires  1  day  and 
the  return  trip  from  3  to  4  days.  At  Pezoapan 
the  supplies  are  unloaded  and  taken  to  the 
mine  on  mules  and  donkeys.  The  cost  of  the 
supplies  is  high  because  of  the  number  of  times 
they  have  to  be  transhipped  and  because  of  the 
distances  they  have  to  be  packed.     The  cost 


of  coke  at  the  mine  is  particularly  high  on 
account  of  the  loss  by  abrasion.  Some  sup- 
plies have  to  be  packed  from  Balsas  to  the 
mine  because  the  packers  who  take  the  bullion 
out  must  have  some  return  freight.  The  cost 
of  the  principal  supplies  is  as  follows,  in 
United  States  currency : 

Posts,  7  ft.  long,  oak $0.37 

Caps,  5  ft.  long,  oak 0'25 

Lagging,  6  ft.  long,  oak 0'07 

Charcoal,  per  ton  7'00 

Coke,  per  ton,  Mexico  City.      11 '00 

Coke,  per  ton.  Balsas 15'36 

Coke,  per  ton,  Reforma  mine      28*00 

Mine  bosses,  per  day    TOO 

Miners,  per  day 0'75 

Labourers,  per  day 0'50 

Detailed  accounts  have  not  been  kept 
but,  taking  the  total  charge  for  6  months  at 
$67,289*51  and  the  tons  mined  at  7940,  the 
cost  is  $8'48  per  ton  for  mining  and  smelting. 
Refining  charges  and  freight  are  $6'05  and 
metallurgical  losses  about  $8"50,  making  a 
total  of  $23'03  per  ton.  These  costs,  however, 
cover  every  charge  and  include  all  construc- 
tion work,  besides  development. 

The  pyrite  ores  of  the  Reforma  are  almost 
identical  in  composition  with  those  of  Mt. 
Lyell  in  Tasmania,  and  could  be  mined  and 
treated  in  the  same  way.  Analyses  may  be 
compared  thus  : 

The  future  plans  for  the  mine,  dependent 

Mt.  Lyell. 

Tr.  ...  —              065  0-70           0-39 

470  ...  235           0  73  075           0  60 

4010  ...  4030  4202  4476  39-88 

Tr.  ...  —             _  _              _ 

160  ...  896           4  09  200           6-38 

4680  ...  4650  4877  4476  46-60 

370  ...  —             130  150           2-10 

—  ...  —            030  023           — 

825  ...  200           1-50  112           174 

Oil  ...  007           007  08           006 

on  the  construction  of  the  railroad  from  Balsas 
to  Pezoapan  and  the  construction  of  either  a 
narrow-gauge  railroad  or  an  aerial  tram  from 
the  mine  to  Pezoapan,  mvolve  the  develop- 
ment of  power  in  the  Balsas  river  and  the  erec- 
tion of  a  pyritic  smelting  plant  of  about  1500 
tons  daily  capacity.  These  plans  are  entirely 
feasible,  and  when  carried  out,  should  place 
the  mine  in  the  ranks  of  the  big  mines  of  the 
world.  The  average  value  of  some  1 1,000,000 
tons  of  developed  ore  is  $7"53  per  ton,  and 
working  costs  should  not  exceed  $4'50  per  ton. 
The  railroad  from  Balsas  to  Pezoapan  has 
been  surveyed  and  a  subsidy  of  7500  pesos 
per  kilometre  has  been  offered  by  the  State 
and  Federal  governments. 


METALLURGY  AT  THE  GLOBE  &  PHOENIX 


By  H.  T.  BRETT. 


THE  Globe  &  Phoenix  mine  is  so  well 
known  as  the  premier  gold  producer  of 
Rhodesia  that  it  is  not  necessary  for  me 
to  give  its  history  ;  suffice  it  to  say  that  the 
Globe  is  not  now  being  worked  and  that  the 
Phoenix  suddenly  acquired  fame  when  an  en- 
richment was  found  extending  several  hundred 
feet  above  and  below  a  horizontal  dike  at  a 
vertical  depth  of  1700  ft.  The  increase  in 
the  value  of  the  ore  may  be  gauged  by  the 
fact  that  the  reserve  at  the  end  of  1910  was 
178,221  tons  averaging  33'9  dwt.  per  ton,  as 
compared  with  106,155  tons  averaging  11  dwt. 
at  the  close  of  1907.  This  ore  contains  suffi- 
cient antimony  in  the  form  of  stibnite  to  make 
its  treatment  difficult  both  as  regards  cost  and 
recovery.  Much  time  and  money  have  been 
spent  in  studying  the  question,  and  as  the  new 
plant  is  giving  good  results,  I  feel  that  the 
publication  of  details  will  be  helpful  to  others 
confronted  with  a  similar  problem.  It  is  not 
claimed  that  the  method  now  adopted  is  in 
the  nature  of  a  new  departure  in  metallurgy, 
but  rather  a  combination  of  known  processes 
applied  to  suit  local  conditions. 

The  ore  is  a  hard  white  quartz,  and,  as  the 
following  analysis  shows,  with  the  exception 
of  antimony,  is  singularly  free  from  base 
metals  : 

o/ 
/o 

Silica  and  insoluble 76'32 

Antimony 0  73 

Iron 2-58 

Sulphur 0-91 

Lime  (CaO) 1'21 

Magnesia  (MgO) 6"44 

Arsenic Trace 

Copper Trace 

Gold 32  dwt.  per  ton. 

Silver 3  dwt.  per  ton. 

The  stibnite  is  found  in  irregular  patches 
throughout  the  mine,  at  some  places  fairly 
massive  and  free  from  gold,  and  at  others 
intimately  mixed  with  the  quartz.  In  the 
rich  ore  (3  oz.  gold  per  ton  and  over)  the  pro- 
portion of  stibnite  increases  up  to  3%  and  the 
pyrite  is  high  in  gold.  Generally  about  75% 
of  the  gold  is  free  and  recoverable  by  amal- 
gamation ;  a  considerable  proportion  of  the 
'  rusty  '  or  '  coated  '  gold  is  not  caught  on  the 
plates  but  can  be  recovered  in  grinding-pans. 
An  ore  low  both  in  antimony  and  gold  pre- 


sents a  hopeless  problem  unless  the  gold  can 
be  liberated  and  caught  by  fine  grinding.  The 
antimony  has  an  injurious  effect  on  cyanida- 
tion  owing  to  its  easy  solubility  in  alkaline 
solutions  and  its  property  of  robbing  the  cya- 
nide of  the  oxygen  required.  An  example  of 
this  can  be  given  in  the  case  of  the  ore  under 
discussion  where,  in  cyaniding  sand  and  slime 
with  everything  conducive  to  a  good  extrac- 
tion, the  presence  of  only  1%  stibnite  makes 
an  extraction  of  more  than  20%  of  the  gold 
practically  hopeless.  The  concentration  of 
antimonial  gold  ore  is  also  difficult  owing  to 
the  tendency  of  antimony  to  slime.  In  the 
present  instance  the  question  was  further  com- 
plicated by  the  fact  that  a  reduction  plant  was 
already  in  operation  at  the  mine,  and,  on  ore 
assaying  up  to  12  dwt.  gold  per  ton,  was  giving 
good  results.  Moreover,  the  surface  space 
available  was  so  limited  as  to  preclude  a  radi- 
cal re-arrangement  of  the  plant.  The  pros- 
pects of  the  rich  ore  continuing  had  to  be  care- 
fully considered,  and  the  position  in  June  1909, 
when  experiments  commenced,  made  it  neces- 
sary for  a  metallurgist  to  proceed  with  cau- 
tion. Fortunately  the  ore  has  proved  per- 
sistent and  a  further  extension  of  plant  will 
probably  be  made. 

The  original  plant,  erected  ten  years  ago, 
was  designed  on  the  lines  usual  when  dealing 
with  a  free-milling  ore  and  consisted  of  a  40- 
stamp  mill,  a  cyanide  leaching  plant,  and  a 
slime  decantation  plant.  The  presence  of  an- 
timony soon  began  to  make  itself  felt,  and  in 
the  sand  and  slime  plant  the  extraction  dropped 
to  40%  and  30%  respectively.  It  was  dis- 
covered, however,  that  if  the  slime  was  run 
direct,  without  treatment,  to  dams,  and  stored 
there  for  about  six  months,  and  allowed  to 
'  weather,'  or  oxidize,  and  then  broken  up  and 
pumped  to  the  slime  plant,  the  extraction  was 
raised  to  75  or  80%.  This  course  was  hence- 
forth adopted  as  far  as  the  slime  was  con- 
cerned, and  it  was  naturally  imagined  that  the 
same  result  would  ensue  as  regards  the  sand. 
But  extended  trials  proved  otherwise.  After 
a  close  investigation  of  the  sand  then  being 
treated,  it  was  found  that  the  antimony  and 
pyrite  were  in  a  much  coarser  state  than  in 
the  slime  ;  moreover,  the  operation  of  the 
sand-plant  was  handicapped  by  the  presence 
of  coarse  particles  of  ore  due  to  broken  screens. 


51 


52 


THE    MINING    MAGAZINE 


Finally  '  rusty  '  coarse  gold  was  beginning  to 
appear,  and  as  there  were  then  no  grinding 
appliances  to  save  it,  a  further  loss  in  the 
sand-residue  was  inevitable.  Numerous  ex- 
periments were  made  in  aeration,  length  of 
treatment,  and  fine  grinding  and  amalgamation, 
but  all  with  unsatisfactory  results,  although 
the  last  mentioned  method  proved  encour- 
aging. An  endeavour  was  then  made  by 
the  erection  of  two  grinding-pans  in  the  mill 
to  re-grind  the  coarsest  of  the  sand,  and,  by 
the  additional  installation  of  sorting-belts  and 
jigs,  to  eliminate  as  much  antimony  as  pos- 
sible before  the  ore  reached  the  stamps.  The 
pans  did  fairly  good  work  as  far  as  saving  of 
the  coated  gold  was  concerned,  but  were  found 
insufficient  in  number  to  cope  with  all  the 
coarse  sand,  while  the  sorting  and  jigging  de- 
partment (owing  to  the  tendency  of  antimony 
to  shatter  into  minute  fragments)  prove  dis- 
appointing. 

The  extraction  obtained  by  treating  74,492 
tons  durmg  the  year  1909  was: 

Percentage 
Extraction     of  content 
Dwt.  per  ton    extracted 

Extracted  in  mill 15'92  75"66 

„         from  sand 1*17  5'56 

,,         from  slime  partly 

weathered 0'76  3*61 

total 17'85  84*83 

Left  in  sand-residue 2'77  13'17 

Left  in  slime-residue  partly 

weathered 0'42  2'00 

Original  assay  of  ore 21*04     100*00 


The  extraction  of  84*83%  for  the  year  1909 
is  not  alarmingly  low,  but  occasionally  when 
the  mill  for  several  days  was  engaged  in 
crushing  development-ore  from  the  enrich- 
ment close  to  the  dike,  with  a  pulp  assaying 
from  60  to  100  dwt.  gold  per  ton,  the  extrac- 
tion dropped  (because  of  the  antimony)  to 
about  75%,  leaving  a  residue  containing  about 
15  dwt.  As  the  reserve  of  rich  ore  had  in- 
creased, the  management  decided  to  take  steps 
to  improve  the  extraction.  In  doing  so  the 
following  points  had  to  be  remembered  : 

(1)  That  a  plant  already  existed  at  the  mine. 

(2)  That  about  75%  of  the  gold  content  could 

be  obtained  by  amalgamating  and 
grinding. 

(3)  That  a  good  extraction  could  be  obtained 

on  slime  up  to  6  dwt.  by  storing  in 
dams  and  weathering  for  about  6 
months  before  cyanide  treatment. 


(4)  That   advantage    must    be   taken   of  the 

brittleness  of  the  antimony  to  grind 
the  sand  finely,  and  so  force  the  anti- 
mony into  the  slime,  where, by  weather- 
ing, it  would  be  rendered  harmless. 
The  fine  sand  remaining  to  be  leached 
would  then  have  but  little  antimony 
left  to  interfere  with  its  treatment. 

(5)  That  the  ore  reserve  in  the  mine  was  in- 

creasing in  value. 

To  make  the  experiments  on  a  large  scale 
10  stamps  were  set  apart,  with  2  grinding- 
pans  followed  by  Wilfley  and  canvas  tables. 
Trials  were  made  on  ore  assaying  from  11  to 
25  dwt.  per  ton.  In  all  cases  the  results 
showed  an  extraction  of  over  90%,  in  fact,  on 
ore  up  to  15  dwt.,  the  sand  caught  after  fine 
grinding  was  of  so  low  a  value  that  cyaniding 
was  unprofitable.  The  conjecture  that  finer 
grinding  would  drive  most  of  the  antimony 
into  the  slime  proved  correct,  while  the  slime 
(50%  of  the  tonnage  milled)  invariably  had  an 
original  value  about  50%  higher  than  the  sand, 
and  as  the  slime  by  exposure  to  the  atmos- 
phere proved  amenable  to  cyanidation  a  big 
advance  was  made  in  the  successful  solution 
of  the  problem. 

All-roasting  of  the  ore  also  gave  good  re- 
sults. If  the  ore  increased  greatly  in  value 
this  process  would  probably  have  proved  the 
best,  but  its  adoption  meant  a  dislocation  of 
existing  arrangements,  besides  a  large  capital 
outlay. 

Armed  with  the  experience  thus  furnished, 
the  alterations  were  commenced  early  in  1910 
and  the  full  plant  was  running  in  December 
of  the  same  year.  The  ore  is  now  trammed 
to  the  crusher-house,  to  fall  on  grizzlies  with 
bars  placed  2  in.  apart.  The  fine  passes  into 
a  storage-bin  ;  the  oversize  is  partly  shovelled 
and  partly  runs  into  two  15  by  9  in.  Blake - 
Marsden  crushers, and  thence  falls  into  another 
bin.  This  bin  has  iron  doors  discharging  to 
an  18-in.  belt-conveyor,  which  takes  it  to  a 
washing-trommel.  This  trommel  is  10  ft. 
6  in.  long  by  5  ft.  6  in.  diam.  at  the  large  and 
2  ft.  9  in.  at  the  smaller  end,  perforated  with 
Ih  in.  holes  for  the  first  four  feet  of  its  length 
and  i  in.  holes  for  the  remainder,  and  revolves 
at  18  r. p.m.  The  fine  drops  through  the  li  in. 
holes  to  another  18  in.  belt-conveyor,  while 
the  oversize  passes  along  the  trommel  and, 
after  being  washed,  to  a  33  in.  sorting-belt 
travelling  at  100  ft.  per  min.,  allowing  part  of 
the  massive  stibnite  (2  ton  to  1  ton  per  day) 
to  be  picked  and  stored  pending  further  treat- 
ment. This  sorting-belt  delivers  the  ore  to 
the  same  belt  as  the  fine  from  the  trommel, 


JULY,    1911 


53 


and  is  conveyed  to  mill-bins  having  a  capacity 
of  500  tons.  The  ore  is  distributed  in  these 
bins  by  means  of  two  18  in.  shuttle-belts  de- 
livering into  two  revolving  chutes.  The  mill 
consists  of  40  stamps,  each  of  1250  lb.,  and 
has  been  in  use  now  for  ten  years.  Each 
stamp  drops  102  times  per  minute  and  crushes 
54  tons  per  day  through  a  25-mesh  screen, 
followed  by  the  usual  amalgamated  copper- 
plate table.     Three  feet  of  the  bottom  end  of 


the  value  of  the  tailing  unduly.  The  concen- 
trators precede  the  re-grinding  plant,  as  the 
antimony  is  saved  easiest  when  in  coarse  par- 
ticles. It  was  also  deemed  advisable  to  im- 
poverish the  slime  passing  to  the  storage  dams 
for  weathering. 

The  fine  slime  overflowing  the  classifiers 
passes  direct  to  the  blanket-tables,  while  the 
sand  goes  to  the  vanners.  The  antimony  and 
pyrite,   containing  about   70%   of  silica  and 


MAP   OF  SOUTHERN  HHODESIA,    SHOWING   THE  POSITION   OF   THE   GLOBE   <C  PHCENIX  MINE. 


the  table  is  covered  with  a  blanket  to  catch 
the  coarse  particles  of  '  rusty  '  gold  that  refuse 
to  amalgamate.  This  product  is  afterward 
amalgamated  in  a  barrel.  The  tailing,  on 
leaving  the  plates,  runs  into  classifiers  each 
36  by  36  by  30  in.  (one  to  each  10  stamps) 
where  the  slime  is  separated,  while  all  the 
sand  passes  to  6  Record  vanners  (5  in  use 
and  1  spare).  Concentrators  were  installed 
to  extract  as  much  of  the  antimony  and  pyrite 
as  possible,  and  also  to  act  as  a  check  in  case 
any  sudden  addition  of  rich  ore  might  raise 


other  insoluble  matter,  pass  from  the  tables 
to  launders  with  a  steep  incline  to  a  Frenier 
pump,  by  which  they  are  elexated  about  16  tt., 
and  run  to  two  settling-tanks  at  the  concen- 
trate-roasting plant.  The  tailing  from  the 
vanners  then  passes  into  10  grinding-and- 
amalgamatmg  pans  running  at  55  r.p.m. 
These  pans  require  about  8  hp.  per  pan  and 
treat  160  tons  per  day.  The  fine  pulp  from 
the  pans,  together  with  the  overflow  of  the 
classifiers  at  the  head  of  the  vanners,  passes 
over  a  blanket-table  58  ft.  wide  by  3S  ft.  long 


54 


THE    MINING    MAGAZINE 


divided  into  strakes  each  24  in,  wide.  The 
blankets  are  removed  at  regular  intervals  and 
washed  in  pointed  boxes.  The  fine  concen- 
trate from  these  boxes  runs  into  the  same 
Frenier  pump  as  the  concentrate  from  the 
vanners,  and  is  pumped  to  the  roasting-plant. 
The  pulp  now  finally  leaves  the  mill  building 
and  flows  to  the  sump  of  the  tailing-pump. 

The  following  figures,  taken  over  a  week's 
run,  illustrate  the  extraction  obtained.  In 
crushing  such  rich  ore  it  is  difficult  to  prevent 
violent  oscillations  in  the  grade  (varying  from 
20  dwt.  to  60  dwt.  per  ton)  with  corresponding 
variations  in  the  value  of  the  sand-residue. 

Extraction  in  Mill  and  Accessories. 

Gold         Stibnite        Pyrite 
Dwt.  %  % 

Screen  discharge 36'0       1*02        1*69 

Leaving  plates 15*0 

Slime  overflow  from  classi- 
fiers (20%  total  tonnage)  12*0       2*02       2'30 

Sand  from  classifiers  (80% 

of  total  tonnage) 16*0       0*76       0*86 

Sand  leaving  vanners  and 

entering  pans 11  '25     0*17       0*54 

Pulp  leaving  pans 6*25 

Pulp  from  pans  running 
on  blanket  -  table  and 
slime  from  classifiers...   6*50     0*67        1*20 

Pulp  leaving  blanket- 
tables  and  entering 
cyanide  plant 6*00     0*51        1*10 

Total  percentage  extrac- 
tion   83*50  50*00     35*00 

Sand  caught  in  sand-col- 
lectors, 50%  of  mill- 
tailing 4*5       0*4         0*85 

Slime  run  to  dams  for 
weathering  and  subse- 
quent treating 8*5       0*75       1*36 

Sizing  Results, 

Mesh  Used. 

-1-40         +60       -1-100      -1-150    —150 

%  °/o  °/  %  % 

Battery-screening  ,.,23*4  18*3  22°4   10*4  25*5 

Feed  to  pans 32*8  20*6  25*0     7*6  14*0 

Discharge  from  pans  0*2  1*6  34*2   19*8  42*2 

Pulp  leaving  mill...  0*1  1*0  17*8   15*4  65*7 

Sand  in  collectors...   0*1  0*8  24*2  29*2  45*7 

Slime  to  dams Nil  Nil  Nil     2*3  97*7 

.The  pulp  finally  leaving  the  mill  flows  to  a 
Forwood-Down  pump.  A  tailing- wheel  had 
been  in  use  for  ten  years,  but  as  the  altera- 
tions necessitated  a  much  higher  elevation  of 
the  pulp,  and  space  being  limited,  a  pump  was 
installed.  After  being  elevated  51  ft.  by  the 
tailing-pump  the  pulp  flows  down  a  launder 


to  a  large  spitzkasten  61  by  6  by  6  ft.  where 
the  fine  sand  is  separated  for  the  sand-collec- 
tors, while  the  slimy  water  overflows  to  the 
slime-collectors.  The  sand-collectors  consist 
of  4  steel  tanks,  each  30  ft.  diam.  by  7  ft, 
deep,  superimposed  over  4  steel  leaching- 
tanks,  30  ft.  diam.  by  8  ft.  deep.  The  sand 
produced  is  about  50%  of  the  tonnage  milled, 
and  owing  to  its  fineness  the  collectors  are 
only  filled  to  a  depth  of  6  ft.,  each  charge 
being  subjected  to  about  six  to  eight  days 
actual  treatment  in  the  lower  tanks.  Sizing 
tests  of  the  sand  show  : 

Mesh  % 

+    40 0*1 

+    60 0*8 

+  100 24*2 

+  150 29*2 

-  150 45*7 


100*0 


As  already  mentioned  the  extraction  on  the 
sand  had  been  unsatisfactory,  and  even  after 
the  alterations  the  residue  from  high-grade 
ore  (over  30  dwt.)  is  too  valuable  to  be  re- 
jected. Numerous  attempts  have  been  made 
to  reduce  the  sand-residue  to  an  economic 
limit ;  for  instance,  several  tons  were  ex- 
posed to  the  action  of  the  atmosphere  for 
months  but  with  an  indifferent  result.  The 
largest  loss  is  in  the  minus  150  product,  which 
contains  practically  all  the  fine  antimony  and 
pyrite. 

As  before  and  after  the  alteration  of  the 
plant  it  had  been  found  necessary  to  crush 
rich  ore  on  various  occasions,  the  schedule 
at  the  top  of  the  next  page  is  interesting. 

It  will  be  observed  that  as  soon  as  the 
antimony  in  the  sand  charge  exceeds  (on  high- 
grade  ore)  0*2%,  the  extraction  drops  rapidly. 
As  before  the  alteration  to  the  plant  the  sand 
treated  constituted  80%  of  the  tonnage  milled, 
as  against  only  50%  at  the  present  time,  the 
general  loss  in  residue  per  ton  milled  is  now 
obviously  much  lower  in  proportion  than  the 
above  figures  indicate. 

The  overflow  of  slime  and  water  from  the 
large  spitzkasten  placed  over  the  sand-tanks 
goes  to  two  35  by  14  by  17ift.  collectors  where 
the  clear  water  is  drawn  off  and  pumped  back 
to  the  mill-supply  tank,  while  the  thick  slime 
is  drawn  from  the  bottom  and  pumped  to  the 
storage-dams.  As  soon  as  the  accumulation 
has  attained  a  thickness  of  about  6  ft.  and 
contains  about  10,000  tons  of  dry  slime,  the 
stream  of  thick  untreated  current  is  turned 
into  another  empty  dam  and  so  on.      At  the 


JULY,    1911 


55 


Results  on  Rich  Ore. 


B 

F.FORE  Alterations 

After  Alterations 

Battery 

Screening 

Dwt. 

Antimony 
in 

sand 
% 

Sand  Charge 
Dwt. 

Sand  Residue 
Dwt. 

Gold  Extracted 

% 

Sand  Charge 
Dwt. 

Sand  Residue  ;  Gold  Extracted 
Dwt.                        % 

15 

0*1 

4-0 

2"5 

37'5 

1*5 

•50 

66'6 

17 

O'l 

5'5 

3*5 

36-3 

2-0 

75 

62"5 

20 

0-15 

6*0 

375 

37-5 

2-5 

roo          60"o 

25 

0"20 

8'0 

5'00 

37"5 

37 

r50 

60'0 

30 

0*26 

lO'O 

7"00 

30-0 

4-5 

2"0 

55'5 

40 

0*42 

12"0 

9"50 

277 

57 

3"50       1       38"6 

60 

0'60 

17-0 

12"00 

29"4 

7"5 

5-00             33-3 

80 

0'81 

20-0 

16"00 

20*0 

875 

6*50 

257 

100 

no 

25"0 

20"00 

20'0 

12-00 

8-50 

29'1 

FLOW-SHEET 

ILLUSTRATING  SCHEME 

OF  TREATMENT. 


Tine 


Main  ShaFt 

Bin 

I 

Tramway 

Grjz  zites 

I 


Oversiz  e 
2  Jaw  Crushers 


Fme    Bin 
18"  Belt   Conveyor 
washing   &  Sizing  Trommel 


Fine 


Oversrze 

I 

33*Sorrjng  Beff 


Ore 

_) 


finrimon^ 


I8"Belr  Conveyor 
DislTiburmg  Belts  i  Revolving  Chufes 
Mill     Bins 
40-5famp  Mill        ^ 


Fururc  Treatment 


Copper  Plate  Tables 
Classtfrers 

I 


"^ 


Sand- 
5  Record  Vanners     <- 


Slime  &  Surplus  Warer 


Concenrrare 
Collecnng  Tanks 

Dryrng  Floor 
SucKei"  Elevaror 
Merron  Roas^lng  Furnace 
Roasred  Concentrate 
Pusti  Conveyor 

BucKer  Eievaror 
1 
2  Grinding  i  Amalgamating  Pans 

Blanker  Table 

Fre'nier  Pirmp 

2  Sfime   Collectors 


Tailing 
10  Grinding  &  Amalgamating  Pans 


1 

Blanker-  Tables 

Tailing  Pump 

ClassiFier 


^ 


Fine  Sand 

I 

Treatment  Vafs 


^ 


Sand  Residue 
Waste  or  Re  rreot 


Gold  Solution 


I 

Sri  me 

I 

2  Slime  Agifafors 

24  ton  Dehne  FiUer  Press 
I 


Clear  OverHow  \ 
cyanide  solution 


Residue 
I 
Towaste  or  Rer^ea^me^r 


Gold   Solution 


Slime 

I 
Dams 

Slime  Mixer 
I 
TrcaTmenr  Vats 

L- 


Slime  I  Water 

t 

Sltmc  Colleclors 

I 


Clear  . 

overflow  water    ^ 


Slline  Residue 

I 

To  wasrc 


1 

Cold  SoluMon 


Zinc  Exrracror  Boxes 


1—5 


56 


THE  MINING  MAGAZINE 


end  of  two  months  of  dry  weather  the  surface 
of  a  dam  is  sohd  enough  to  permit  of  its  being 
ploughed  to  a  depth  of  about  a  foot,  and  after 
a  further  week,  this  ploughed  portion  is  har- 
rowed and  allowed  to  stand  for  another  month 
or  so,  or  until  the  loose  slime  appears  per- 
fectly dry  and  oxidized.  The  shme  is  then 
shovelled  into  trucks  and  goes  to  a  mixer.  To 
permit  of  continuous  weathering  of  the  slime 
before  cyanidation,  it  is  necessary  that  several 
dams  be  in  use  at  once,  so  that  one  is  being 
filled, one  is  drying,  and  two  are  being  ploughed 
and  harrowed. 

The  mixing  of  the  slime  is  done  in  a  steel 
tank,  4  ft.  diam.  by  3  ft.  6  in.  deep,  in  which  is 
placed  a  steel  cone  with  the  large  end  rivetted 
to  the  top  edge  of  the  tank,  while  the 
apex  of  the  cone  has  an  opening  of  about 
18  in.  diam.  and  reaches  to  within  12  in. 
of  the  bottom  of  the  tank.  In  this  open- 
ing revolves,  at  a  speed  of  200  r.p.m.,  a 
four-bladed  propeller  connected  to  vertical 
shafting  and  driven  by  means  of  pinion  and 
spur-wheel  gearing.  The  slime  has  to  pass 
the  blades  of  the  propeller  and  is  then  forced 
up  between  the  side  of  the  cone  and  tank, 
passing  out  of  a  6  in.  opening  in  the  side  of 
the  latter.  Cyanide  solution  is  added  to  the 
mixer  to  make  a  pulp  of  about  li  parts  of 
solution  to  1  of  slime.  The  pulp  on  leaving 
runs  into  a  tank  or  steady-head,  connected  to 
the  suction  of  a  double-acting  centrifugal 
pump,  which  elevates  the  pulp  into  the  decan- 
tation  plant.  The  capacity  of  the  mixer  itself 
is  about  12  to  15  tons  of  dry  slime  per  hour, 
and  20  hp.  is  required  to  operate  the  entire 
apparatus.  The  plant  for  the  actual  cyaniding 
was  erected  about  5  years  ago  and  is  of  the 
usual  decantation  type,  consisting  of  two  col- 
lectors 35  by  14  by  172  ft.,  six  treatment  tanks, 
also  35  by  14  by  17i  ft.,  three  clarifying  tanks 
20  by  5  ft.,  with  pipe  connections,  and  centri- 
fugal pumps  for  transfer  of  slime  and  decan- 
tation of  solution  into  clarifiers  and  sumps. 
This  plant  has  a  capacity  of  about  3000  tons 
of  slime  per  month  of  an  original  value  of  4 
dwt.  per  ton,  but  when  richer  material  is 
treated  the  capacity  will  be  less.  To  obviate 
this  the  erection  of  a  vacuum-filter  plant  is 
under  consideration.  The  total  cost  of  treating 
slime  is  3s.  6d.  per  ton. 

The  extraction  obtained  on  weathered  slime 
of  a  value  of  4  dwt.  is  from  75  to  80%,  while 
on  the  same  slime  if  taken  direct  from  the  mill 
the  extraction  drops  to  about  30%.  For  an 
extra  expenditure  of  6d.  per  ton  therefore  in 
the  handling  and  weathering  of  slime  in  the 
dams,  a  further  extraction  of  45%  is  eflfected. 


The  concentrate  from  the  vanners  and  blan- 
ket-tables is  elevated  by  means  of  a  Frenier 
pump  into  two  small  collecting-tanks  12  ft. 
diam.  by  4  ft. deep,  provided  with  filter-bottoms, 
and  an  overflow  launder  round  the  periphery, 
which  takes  the  clear  water  and  delivers  into 
the  sump  of  the  tailing-pump.  The  concen- 
trate collected  each  day  is  allowed  to  drain, 
and  then  shovelled  upon  a  sloping  floor  to  dry 
for  24  hours  and  thence  fed  by  means  of  a 
chain-and-bucket  elevator  into  the  top  hearth 
of  the  roasting- furnace.  This  is  a  Merton  3- 
hearth  fui"nace  with  a  finishing  hearth-exten- 
sion. On  each  hearth  are  four  solid  knife- 
edge  rabbles,  while  the  finishing  hearth  has 
three  water-cooled  rabbles  with  diamond- 
pointed  feet.  All  the  rabbles  run  at  two  revo- 
lutions per  minute. 

The  successful  treatment  of  an  antimonial 
gold  concentrate  is  always  difficult.  Various 
experiments  on  the  raw  concentrate  gave  ex- 
tremely poor  results,  but  roasting  experiments 
held  out  a  much  better  prospect,  especially 
when  compared  with  the  only  other  course 
open,  namely,  bagging  and  shipment.  When 
an  ore  or  concentrate  containing  antimony  is 
roasted,  the  volatile  trioxide  is  first  formed, 
which  on  coming  into  contact  with  air  forms 
the  infusible  and  stable  tetroxide.  Again,  when 
antimony  or  stibnite  is  roasted  in  presence  of 
the  sulphides  of  other  metals,  antimoniates  of 
these  metals  are  formed.  It  is  therefore  im- 
possible to  get  rid  of  all  the  antimony,  while 
it  is  also  found  that,  when  a  large  percentage 
of  this  substance  is  present,  the  ore  on  heating 
swells  considerably  and  becomes  sticky.' 
These  difficulties  can  be  partly  overcome  by 
constant  rabbling  in  the  presence  of  a  large 
proportion  of  sand  or  silica.  Trials  showed 
that  90%  could  be  recovered,  and  it  was  hoped 
that  by  exposing  the  residue  to  the  atmosphere 
in  dumps  from  six  to  twelve  months,  and 
running  it  through  the  large  decantation  slime- 
plant,  this  extraction  could  be  raised  to  at  least 
95%,  The  total  cost  of  the  treatment  of  the  con- 
centrate on  a  large  scale  was  estimated  to  be 
about  25s.  per  ton.  These  figures  have  been 
borne  out  in  practice  ;  a  comparison  with  bag- 
ging and  shipping  to  England,  freight  alone 
costing  £b  per  ton,  emphasizes  the  advantage 
of  roasting  the  concentrate  at  the  mine. 

The  roasted  product  is  discharged  into  a 
push-conveyor,  30  ft.  long  with  flights  12  in. 
wide  running  at  18  strokes  per  minute;  this 
cools  and  conv'eys  it  to  a  small  chain-and- 
bucket  elevator,  which  delivers  it  to  two  5  ft. 
grinding-and-amalgamating  pans,  running  at 
45  r.p.m.,  in  which  cyanide  solution  is  used. 


JULY,    1911 


57 


After  grinding,  the  pulp  flows  from  the  pans 
over  blanket-tables  (which  catch  any  fine 
'rusty'  gold  or  'flowered'  mercury),  thence 
into  a  Frenier  pump,  to  be  elevated  18  ft.  to  a 
classifier,  which  returns  any  oversize  back  to 
the  pans,  while  the  overflow  passes  into  two 
16  by  6  ft.  collectors  provided  with  overflow 
launders.  The  overflow  clear  solution  gravi- 
tates to  a  storage-tank  supplying  the  pans, 
while  the  slime  settles  to  the  bottom  and  is 
discharged  every  24  hours  into  two  16  by  6  ft. 
tanks  having  agitators  running  at  14  r.p.m. 
After  24  hours  agitation,  a  three-throw  pump 
forces  the  pulp  mto  a  ii  ton  Dehne  filter- 
press,  where  the  gold  solution  is  removed  and 
the  cake  washed  and  discharged  (containing 
about  12%  moisture)  into  trucks,  and  dumped 
for  oxidation  and  future  treatment  if  the  gold 
contents  warrant.  The  capacity  of  the  furnace 
is  about  11  tons  per  day  (depending  on  the 
proportion  of  antimony  and  sulphur  present) 
while  the  capacity  of  the  remainder  of  the 
plant  is  double  this,  so,  in  the  event  of  any 
increase  in  output,  the  addition  of  another 
furnace  only  would  mean  that  600  tons  of  con- 
centrate per  month  could  be  roasted,  slimed, 
and  cyanided.  The  whole  of  the  floor  around 
the  pans  and  furnace  and  under  the  filter- 
press  is  cemented,  so  as  to  minimize  loss  of 
gold  in  solution  or  dust. 

An  analysis  of  the  raw  concentrate  shows 
about  65%  silica  and  insolubles,  5%  antimony, 
and  9%  sulphur,  while  the  roasted  product  is 
found  to  contain  3%  antimony  (chiefly  as  anti- 
moniate)  and  0'72%  sulphur  (0'6?'^  existing  as 
sulphate  and  0"12%  sulphide).  It  will  be 
noticed  that  while  a  good  roast  as  regards  the 
expulsion  of  sulphur  is  obtainable,  the  anti- 
mony is  not  so  readily  driven  off.  The  loss 
in  weight  in  roasting  varies  between  25  and 
30%,  depending  on  the  quantity  of  sulphur  in 
the  raw  concentrate.  The  gold  in  the  concen- 
trate varies  between  2  and  15  oz.  per  ton,  and 
in  the  residue  for  22  to  25  dwt.  per  ton.  The 
extraction  has  ranged  between  85  and  90%  and 
an  experiment  on  the  roasted  residue  exposed 
for  only  three  months  to  the  atmosphere  indi- 
cates a  further  extraction.  The  firing  of  the 
furnace  is  done  with  wood  by  native  firemen, 
one  white  man  per  shift  being  in  charge  of 
the  whole  roasting-plant,  although  the  same 
man  could  easily  superintend  the  working  of 
two  more  furnaces.  The  total  labour  is  3 
white  men  and  15  natives  per  24  hours.  Tlie 
running  time  is  about  94%  of  the  possible,  and 
so  far  the  repairs  on  the  whole  roasting  iinit 
have  been  extremely  small.  The  cost  on  a 
basis  of  3  20  tons  per   month   is  as  follows: 


Per  ton. 
s.  d. 

White  and  native  labour  10  0'26 

Fuel  for  roasting    2  171 

Cyanide  3  3-46 

Power    (including  compressed 

air)   3  9*58 

Assays,etc 1  5-09 

General     stores     (zinc,     acid, 

filter-cloth,  oil,  etc.)    2  2T0 

Total 22  10'20 

With  the  addition  of  an  extra  roasting-fur- 
nace,  it  is  anticipated  that  on  600  tons  of  con- 
centrate per  month,  the  total  cost  would  be  re- 
duced to  17s.  6d.  per  ton. 

It  has  been  found  that  the  concentrate  re- 
quires to  be  brought  to  a  high  temperature 
very  slowly,  and  as  the  knife-edge  rabbles  are 
rather  against  this,  steps  are  being  taken  to 
change  most  of  them  for  the  solid  rabbles  with 
diamond-pointed  feet. 

About  60%  of  the  gold  is  obtained  by 
amalgamation  in  the  pans  and  40%  by  cya- 
nide. The  gold  from  both  processes  is  melted 
into  one  bar,  about  965  fine. 

As  the  new  plant  has  been  in  full  operation 
about  three  months  at  the  time  of  writing, 
sufficient  data  are  available  to  estimate  the 
average  extraction,  although,  owing  to  the 
storage  in  dams  of  the  slime  for  six  months, 
the  total  extraction,  including  that  on  the 
actual  slime  produced  each  month,  cannot  be 
given.  As  thousands  of  tons  of  weathered 
slime  have  been  treated,  it  is  an  easy  matter 
to  calculate  the  recovery  as  if  the  slime 
actually  produced  in  any  one  month  had  been 
treated  during  that  period. 

Taking  January  last  as  an  example,  during 
which  6539  tons  was  milled,  the  estimated 
extraction  was  as  follows  (allowing  80%  re- 
covery on  the  slime,  which  would  be  the  result 
after  six  months  lying  exposed  to  the  air) : 

Dwt.  per     Percentage  per 
Source.  ton  milled.       ton  milled. 

Stamps  and  pans  28"94  79"86 

Concentrate    2'41  6*65 

Sand    0*39  r08 

Slime -'•15  5-91 

Total  extracted...  33'89  93"50 

Concentrate-residue  ...  0'21  0'59 

Sand-residue r60  1  "49 

Siime-residue 0'54  4'42 


36"24       lOO'OO 
The  actual  figures  for  January  were  an  ex- 


58 


THE     MINING     MAGAZINE 


traction  of  9r31%  on  an  original  assay- value 
of  35'29  dwt.  The  discrepancy  in  these  figures 
and  those  given  in  the  above  schedule  is  due, 
as  stated,  to  the  fact  that  the  weathered  slime 
from  the  dams  during  the  month  was  only 
about  half  the  value  of  the  actual  slime  pro- 
duced. 

Working  Cost. 

s.      d.     s.      d. 

Mining 6   10'17 

Development 4     O'OO 

Hauling  and   pumping  3     0'71 

13   10*88 

Transport  and  rock- 
breaking  1      1 

Milling  (inclusive  of 
fine  grinding  and 
concentrating)  6     6 

Sand  treatment  1     9'40 

Slime  treatment 1     7"26 

Concentrate    treatment  1      1*15 

General     repairs     and 

maintenance 9' 11 

Bank  chargeson  bullion         4'94 

13     2*86 

General  administration  2     9.33 


Total  cost. 


29  iro7 


As  the  sand-residue  yields  an  unsatisfac- 
tory extraction  on  the  high-grade  ore,  future 
improvements  will  be  required.  One  propo- 
sal is  to  eliminate  the  sand-plant  altogether, 
grind  the  sand  in  tube-mills,  and  convey  it 
together  with  the  present  slime  to  dams,  for 
weathering.  Against  this,  there  is  the  ques- 
tion of  surface  room,  as  a  large  space  is  now 
appropriated  in  exposing  to  the  air  the  present 
slime  (3000  tons  per  month)  and  to  increase 
this  to  6000  tons  per  month  necessitates  double 
the  dam-area.  The  question  of  native  labour 
(always  a  scarce  commodity),  in  attending  to 
the  dams,  affects  the  decision  ;  there  is  also 
the  question  whether  this  sand  can  be  slimed 
and  in  six  months  oxidize  sufficiently  to  be- 
come amenable  to  cyanidation.  As  six  months 
must  elapse  before  this  question  can  be  ascer- 
tained (exposure  to  the  atmosphere  being 
the  essential  factor,  not  to  be  accelerated  by 
any  artificial  means),  it  is  obvious  that  if  at 
the  end  of  that  time  results  are  unsatisfactory, 
the  position  becomes  awkward  and  a  fairly 
large  capital  outlay  is  undertaken  for  no  re- 
sult. Another  suggestion  is  to  erect  a  roast- 
ing-furnace  of  100  tons  capacity,  together  with 
necessary  pans  and  tube-mills,  take  the  sand 
direct   from  the  collectors  and  roast,   slime, 


and  cyanide  it.  This  scheme  would  be  a  little 
more  expensive  than  that  just  mentioned,  but 
it  is  more  certain  of  success  as  far  as  gold  ex- 
traction is  concerned. 

It  is  suggested  now  to  erect  three  large 
roasting-furnaces,  the  necessary  pans,  tube- 
mills,  and  filter-plant,  cut  out  the  present  sand- 
cyanide  plant  (except  the  collectors),  roast, 
slime,  and  cyanide  200  tons  of  old  accumu- 
lated sand  together  with  100  tons  of  current 
sand,  or  a  total  of  300  tons  per  day.  The 
cost  of  treatment  is  not  expected  to  exceed 
8s.  with  a  loss  of  gold  in  the  residue  of  under 
3s.  per  ton.  The  whole  question  is  a  matter 
of  profit  per  ton  and  capital  expenditure  in- 
volved, with  due  regard  to  local  conditions, 
and  should  the  last  named  proposal  be  finally 
adopted — roasting  the  whole  of  the  old  accu- 
mulated and  current  sand — -it  must  be  admit- 
ted that  it  will  be  a  unique  undertaking. 

Carn  Brea  and  Tincroft. — The  latest 
news  of  interest  from  Cornwall  relates  to  the 
rearrangement  of  the  directorate  and  manage- 
ment of  the  Carn  Brea  and  Tincroft  at  Cam- 
borne. For  some  years  Viscount  Clifden, 
one  of  the  lords,  has  taken  a  more  direct  and 
intelligent  interest  in  mining  operations  than 
is  usual  with  the  owners  of  mineral  rights. 
Not  only  has  he  foregone  royalties  but  he  has 
subscribed  capital.  Six  months  ago,  when  it 
was  decided  to  separate  the  tin  and  wolfram, 
he  provided  the  money  for  the  Wetherill 
plant.  The  recent  death  of  the  manager, 
John  Penhall,  gave  him  the  opportunity  of 
pressing  on  the  board  of  directors  the  neces- 
sity of  introducing  new  blood,  and  appointing 
a  man  of  wider  experience  than  the  average 
mine  captain  obtainable  nowadays  locally,  and 
accordingly  Edward  S.  King,  who  has  an 
honourable  record  in  Australia,  was  selected 
as  '  consulting  manager'  with  H.  Swan  Edgar 
as  resident  manager.  The  old  system  of  buying 
supplies  was  discarded  and  in  future  the  re- 
quirements are  to  be  advertised  in  public 
competition.  Frank  Harvey  and  J.  C.  Daubuz, 
who  have  been  on  the  board  for  many  years, 
have  retired  and  Lord  Clifden  is  virtually 
the  controller.  There  is  no  doubt  that  the 
mine  has  sufficient  reserve  of  ore  to  last  for 
some  time,  and  with  the  improved  prices 
obtainable  consequent  on  the  better  separa- 
tion now  possible  and  with  the  decreased  cost 
following  on  reduction  in  the  price  of  supplies, 
some  profits  should  be  made  in  the  near 
future.  In  the  meantime  Mr.  King  will  have 
time  to  turn  round  and  evolve  new  schemes 
for  development  and  treatment. 


THE  CASAPALCA  SMELTER,  PERU 

By  LESTER  W.   STRAUSS. 


THE  Casapalca  smelter  is  the  second 
largest  metallurgical  establishment  in 
Peru  and  though  overshadowed  by  the 
gigantic  Cerro  de  Pasco  it  plays  an  important 
part  in  the  development  of  the  mineral  re- 
sources of  that  country.  It  was  originally  es- 
tablished in  1888  for  the  treatment  of  silver- 
bearing  lead  ores,  and  was  founded  by  Jacob 
Backus  and  J.  Howard  Johnston,  who  had  pre- 
viously made  money  by  brewing  in  Lima. 
With  them  was  associated  Capt.  Henry  Guyer. 
In  1896  the  business  was  incorporated  under 
the  laws  of  New  Jersey  as  the  Backus  & 
Johnston  Co.  The  lead  ores  gradually  became 
scarce  and  copper  ores  were  bought  instead. 
The  silver  was  extracted  by  the  Ziervogel 
process  and  subsequently  black  copper  pro- 
duced. In  1899  this  method  was  abandoned 
and  the  matte  shipped  abroad,  a  policy  which 
is  still  followed.  Alines  were  bought  and  pur- 
chasing contracts  made  for  custom  ore. 

The  smelter  is  situated  on  the  Central  Rail- 
road of  Peru  95  miles  from  Callao,  the  sea- 
port. The  elevation  is  13,600  ft.  above  the 
sea  and  the  inw^ard  trip  occupies  8  hours.  The 
chief  mine  is  the  Natividad,  at  Morococha,  20 
miles  north  on  a  branch  line  of  railway. 
The  company  owns  part  of  this  property  and 
purchases  the  output  of  the  remainder,  known 
as  the  Carmen.  The  ore  from  these  mines 
contains  much  lead  and  zinc  as  well  as  copper, 
necessitating  modifications  of  the  smelting 
plant.  The  present  blast-furnace  was  blown 
in  during  August  1910  and  pot-sintering  was 
started  in  March  of  this  year.  I  propose  to 
give  some  account  of  the  mine  and  follow  the 
ore  to  the  mill  and  smelter,  describing  the  fur- 
nace and  new  pot-roasting  plant. 

At  the  Natividad  mines  the  ore  is  found  in 
three  principal  veins  varying  from  a  few 
inches  to  8  ft.  and  averaging  2  ft.  wide  ;  these 
cut  across  the  stratification  of  limestone,  meta- 
morphosed rocks  (marl  and  slate),  conglomer- 
ate, and  the  eruptive  (andesite  ?).  The  valu- 
able metals  are  silver  and  copper,  with  which 
are  associated  zinc  and  lead.  The  minerals 
predominate  in  the  following  order :  Zinc- 
blende,  galena,  pyrite,  chalcopyrite,  tetrahed- 
rite,  and  occasionally  pyrargyrite,  in  a  quartz 
gangue  ;  the  tetrahedrite  is  argentiferous.  The 
wall-rocks  are  usually  firm;  timbering  being 
necessary  only  where  stopes  are  wide  and  for 


man  ways  and  chutes.  Overhand  stoping  has 
been  used  but  the  present  plan  is  to  change 
to  the  underhand  system.  All  the  hauling  is 
done  through  the  Carlos  Francisco  adit,  which 
cuts  the  vein  of  that  name,  5248  ft.  from  its 
mouth  ;  it  is  straight  the  entire  distance.  No 
hoisting  is  done.  The  above  mentioned  vein 
is  probably  one  of  the  premier  lodes  of  the 
world  in  that  it  has  been  exploited  for  over 
13,120  ft.  on  the  strike,  while  on  the  surface 
it  has  been  traced  16,400  ft. ;  in  depth  it  has 
been  cut  nearly  2300  ft.  vertically  below  its 


Chimbote 


Central  Peru. 

outcrop  or  2550  ft.  on  the  dip.  The  Backus 
&  Johnston  Co.  does  not  own  all  of  the  vein, 
although  controlling  most  of  the  output.  A 
spur  from  the  adit,  where  it  cuts  the  vein, 
extends  2950  ft.  southeasterly  intersecting  the 
Carmen  vein  1640  ft.  below  its  outcrop.  Ore 
from  these  two  veins  is  trammed  by  gravity, 
in  trains  of  4  1-ton  cars,  the  rear  car  being 
fitted  with  a  brake.  The  empties  are  hauled 
back  with  mules.  Electric  lighting  is  used  in 
the  adit.  A  10-kilo.  rail  is  used  with  50  cm. 
gauge  ;  the  average  grade  is  f%.  During  the 
driving  of  the  adit,  459  ft.  was  done  in  one 


59 


60 


THE    MINING    MAGAZINE 


month,  on  contract,  using  two  3l  in.  drills  on 
three  shifts,  the  face  being  3  metres  high,  of 
the  same  width,  and  all  the  broken  rock  being 
trammed  to  the  dump,  at  a  cost  of  £6  per 
metre.    No  timbering  was  necessary  ;  the  rock 
was  of  medium  hardness.  Six  drillers  and  their 
helpers  were  employed  and  about  24  shovel- 
lers and  trammers.     The  ore,  as  sorted  in  the 
stopes,    is    run   to  a  sorting-shed  and  hand- 
jigged.     Coarse  and  fine  concentrates  are  pro- 
'duced;  the  former  is  crushed  and  mixed  before 
going  to  Brown  roasters  (or,  as  now  planned, 
to   the  sintering-pots)   and  the  latter  to  the 
bedding-floor  prior  to  roasting.    The  mineral- 
ized rock  not  picked  clean  in  sorting  is  sent  in 
separate  cars  to  the  mill ;  the  waste-rock  is 
used  for  filling  old  stopes.     About  125  tons  of 
sorted  ore  and  milling  ore  are  trammed  out 
per  day. 

The  output  for  the  mill  is  dumped  over  a 
H  in.  grizzly,  the  coarse  passing  through  a 
Blake  crusher,  the  reduced  ore  and  the  fine 
going  then  to  the  stamps,  of  which  there  are 
10  with  a  weight  of  750  lb.,  a  drop  of  7  inches, 
90  times  per  minute.    A  i  inch  screen  is  used, 
through  which  the  crushed  material  from  each 
battery  passes  to  a  5-mesh  trommel ;  the  coarse 
material  (about  15%)  being  discarded  while  the 
fine  passes'to  spitzkasten,  the  coarse  discharge 
of  which  goes  to  2  Wilfley  and  2  Overstrom 
tables.     These  are  manipulated  so  as  not  to 
discard  all  the  silicious  gangue,  the  object  of 
the  concentration  being  to  increase  the  silver, 
copper,  and  iron  contents.     A  recovery  of  66% 
of  the  metal  contents  is  effected.     The  ore 
averages  15  oz.  silver  and  0'8%  copper, the  tail- 
ing 5  oz.  silver  and  0'5%  copper^and  the  con- 
centrate 46  oz.  silver  and  2'6%  copper.     An 
approximateanalysis  of  the  concentrate  shows: 
SiOs  7'5%;   Fe  24%;   AloOs0"6%;    Zn  11%; 
Pb  14%  ;    S  32% ;    Cu  2-5% ;  Ag  52  oz.     The 
ratio  of  concentration  is  about  five  to  one.  At 
present  about  70  tons   is   crushed   per   day, 
yielding  nearly    14  tons  of  concentrate.      (A 
new  mill  is  being  erected  with  a  capacity  of 
250  tons  daily  ;  a  No.  7  wet-grinding  Krupp 
ball-mill  is  already  in  place,  the  capacity  of 
which  is   10  to   12  tons  per  hour  through  a 
4  mm.  aperture.     The  crushed  material  will 
pass  to  a  4  mm.  Bunker   Hill  screen.     The 
subsequent  method  of  treatment  will  be  deter- 
mined  by  experiment).     The  concentrate  is 
hauled  to  the  bedding-floor  where  it  is  mixed 
with    the    hand- jigged    concentrate   and    the 
crushed  ore.     The  coarse  hand-jigged  ore  and 
the  custom  ores   are  coarsely    crushed    and 
weighed  out  in  the  proportion  to  make  a  good 
mixture  for  the  blast-furnace ;    then  crushed 


in  a  dry-grinding  Krupp  ball-mill  to  4  mm. 
size  and  wheeled  to  the  bedding-flocr.  There 
the  crushed  ore  and  concentrate  are  mixed  in 
proper  proportion,  and  from  the  beds  so  made, 
charges  are  wheeled  to  the  Brown  roasters. 
The  sintering  plant  will  replace  all  this  pro- 
cess, including  the  Brown  roasters  and  briquet- 
ting  machines. 

Nearly  half  of  the  present  tonnage  treated  is 
custom  ore  and  that  principally  from  the  Car- 
men mine,  which  is  higher  in  silver  and  silica. 
The  ore  coming  from  the  Carmen  vein  proved 
an  excellent  flux  where  so  much  zinc  had  pre- 
viously proved  troublesome  in  smelting.  Pro- 
bably 1000  tons  of  Natividad  ore  is  brought  in 
each  month  ;  this  is  usually  smelted  raw,  only 
the  fine  being  roasted.  From  5200  to  5500 
tons  of  crude  ore  is  treated  per  month.  Of 
the  ores  purchased  practically  all  are  crushed 
fine  and  bedded,  as  already  outlined.  No  cus- 
tom ore  is  milled. 

The  mines  and  smelter  are  under  the  super- 
vision of  the  general  manager,  John  Galliver. 
J.  Howard  Johnston,  one  of  the  founders  of 
the  company,  authorized  the  improvements. 
The  12-hour  shift  is  in  use,  and  the  working 
day  begins  at  6  a.m.  There  are  about  10 
white  men  on  the  technical  staff;  and  1700 
Indians  {cJwlos)  are  employed.  About  250 
tons  of  ore,  limestone,  and  coke  are  delivered 
daily,  either  by  railroad,  in  mine-cars,  or  on 
llamas.  Each  class  of  custom  ore  is  run  to 
its  respective  bin  and  later  weighed  again,  in 
one-ton  charges,  as  already  explamed.  Manual 
labour  is  used  entirely,  and  although  cheap  it 
is  costly  where  so  much  handling  is  done  ;  the 
sintering  plant,  when  in  full  operation,  will 
eliminate  this. 

The  power  plant  is  notable  for  the  absence 
of  steam  engines.  Sufficient  water-power  can 
be  obtained  under  heads  of  90,  238,  and  500 
ft.  respectively.  The  use  of  coal,  at  a  cost 
delivered  of  2"+  per  ton,  would  prove  ex- 
pensive. There  are  two  150-kw.  3-phase  alter- 
nating-current generators,  belt-connected  with 
two  250  hp.,4ft.diam.,5-nozzlePelton  wheels  ; 
a  small  3  ft.  diam.  1 -nozzle  Pelton  wheel,  on 
the  same  shaft  as  the  larger  machines,  is  used 
as  a  helper  when  water  is  scarce.  The  smaller 
wheel  operates  under  500  ft.  head,  and  the 
larger  under  90  ft.  head.  A  5*  kw.  exciter  com- 
pletes the  dynamo-room  equipment,  exclusive 
of  the  switch-board  arrangements.  A  trans- 
former— from  450  to  110  volts — is  used  for 
lighting  purposes.  A  30  hp.  5  ft.  single-nozzle 
Pelton  wheel,  operating  under  70  ft.  head,  is 
used  to  drive  two  6A  Green  blowers,  and  a  3 
ft.  single-nozzle  Pelton  wheel,  under  500  ft. 


JULY,    1911 


61 


head,  is  belt-connected  to  a  No.  6  Root  blower. 
The  air  from  these  blowers  unites  just  before 
entering  the  bustle-pipe.  About  10,000  to 
12,000  cubic  feet  of  effective  air  is  supplied 
per  minute.  Near  the  Carlos  Francisco  adit 
a  3-drill  Imperial  air-compressor  is  belt-con- 
nected to  a  40  hp.  induction  motor  ;  air  at  65 
lb.  pressure  is  supplied  to  two  3j  in.  drills. 
The  machine,  blacksmith,  and  carpenter  shops 
are  sufficiently  equipped  for  ordinary  repair 
work.  A  new  ditch,  to  supply  a  minimum  of 
500hp.  under  238ft.  head,  is  being  constructed. 


ditions  have  been  made  without  apparent  re- 
gard to  proper  arrangements  for  handling 
material,  etc.  ;  the  narrowness  of  the  canyon, 
in  which  the  buildings  are  placed,  compelling 
extension  longitudinally. 

The  roasting  plant  consists  of  two  single- 
hearth  Brown  furnaces  180  ft.  and  240  ft.  long 
respectively  by  10  ft.  wide,  arranged  so  that 
the  discharge-ends  face  each  other.  Petro- 
leum is  used  as  fuel  under  an  air-pressure  of 
12  oz.  The  material  fed  to  the  roasters  is 
4  mm.  size  or  finer  and  has  been  mixed  so  as 


THE  CASAPALCA  SMELTER. 


No  mechanical  sampling  is  done ;  hand- 
quartered  samples  of  ores  and  fluxes  are  taken. 
As  the  contents  of  the  several  ores  do  not  vary 
much,  it  has  been  found  unnecessary  to  adopt 
a  rigid  system  of  sampling.  The  laboratory 
crushing  plant  is  equipped  with  a  20  hp.  in- 
duction-motor driving  several  small  mechanical 
crushers.  For  the  mattes  a  No.  1  dry-grinding 
Krupp  ball-mill  is  used. 

The  present  smelter  occupies  a  terraced 
site  ;  the  buildings  are  of  corrugated  iron  sup- 
ported on  wooden  framework.  While  the  plant 
does  not  represent  good  practice,  as  regards 
design,  it  must  be  borne  in  mind  that  since 
it  was  erected  (1888)  improvements  and  ad- 


to  furnish  a  product  suitable  for  the  blast-fur- 
nace. The  larger  furnace  has  8  cars  on  the 
carrier  chain,  each  fitted  with  9  plows  ;  the 
smaller  furnace  has  6  cars  and  the  same 
number  of  plows  ;  the  chain  moves  at  the 
rate  of  55  ft.  per  minute.  When  a  crust 
accumulates  a  rake  is  fitted  to  one  of 
the  cars  to  break  it  down  ;  as  a  matter 
of  precaution  the  rake  is  usually  attached 
daily.  The  blower,  a  Root  No.  5.  is  driven 
either  with  a  10  hp.  motor  or  connected  with 
a  Pelton  wheel,  either  serving  also  to  drive 
the  carrier  chain  for  the  smaller  furnace,  A 
30  hp.  motor  drives  the  chain  of  the  larger 
furnace,    although    10    hp.    is  sufficient    for 


62 


THE    MINING    MAGAZINE 


ordinary  running  ;  the  excess  is  required  when 
the  ore  becomes  sticky  through  cooHng.  The 
smaller  furnace  can  produce  54'5  tons  of 
roasted  material  per  24  hours,  consuming  3'2 
tons  of  petroleum  ;  the  output  from  the  larger 
furnace  is  68  tons  consuming  3'3  tons  of  petro- 
leum. The  high  price  of  coal,  the  better 
roasting  with  less  labour,  and  more  mobility 
in  operations,  made  the  use  of  petroleum  desir- 
able. The  oil  comes  from  Lobitos  in  Northern 
Peru  and  costs  ^3'4  delivered  at  the  smelter  ; 
about  220  tons  is  consumed  per  month.  There 
are  two  flues  to  each  furnace  ;  previously  one 
flue  was  used,  but  the  additional  one  has  re- 
sulted in  better  desulphurization  due  to  the 
increased  draft.  About  70%  of  the  sulphur  in 
the  charge  is  driven  off^;  there  appears  to  be 
a  slight  loss  of  zinc  and  lead,  but  little  flue- 
dust  is  made.  The  following  approximate 
analyses  indicate  the  nature  of  the  material 
charged  and  the  roasted  product : 

Charge.  Roasted  product. 

o/  o/ 

SiOo 25°0  ...  27°0 

Fe  15'6  ...  18'0 

CaO r5  ...  3"5 

Zn  lO'O  ...  9'2 

Pb  irO  ...  10*3 

AI2O3  4-4  ...  2T 

S 24-0  ...  7*6 

Cu  5'0  ...  6"4 

Silver  ...  45  oz.  per  ton  ...  50oz.  per  ton. 

Reduction  in  weight  due  to  roasting  amounts 
to  10%.  The  product  requires  briquetting  to 
make  it  suitable  for  the  blast-furnace.  The 
adoption  of  the  sintering  process  has  tended 
toward  lower  cost,  better  desulphurization,  a 
more  desirable  product  for  the  blast-furnace, 
and  less  flue-dust.  The  roasted  ore  is  wheeled 
to  a  cooling-floor  to  be  fed  later,  with  flue- 
dust  and  calcined  limestone,  to  a  long-trough 
helical-screw  mixer  and  then  elevated  to  a  bin 
behind  a  briquetting  machine  of  the  White- 
Boyd-Chisholm  type.  Six  bricks  (each  3  by 
4i  by  8i  in.)  are  made  per  stroke  ;  the  average 
weight  per  brick  is  8f  lb.  The  average  daily 
capacity  is  about  30,000  bricks.  Each  day's 
output  is  stacked  separately ;  samples  are 
taken  by  knocking  off  a  fragment  from  some 
of  the  bricks  as  they  are  being  stacked.  From 
the  stack-pile  the  bricks  are  put  into  barrows 
and  wheeled  to  the  blast-furnace.  Considerable 
labour,  although  cheap,  is  necessary  for  mov- 
ing the  product. 

The  smtering  process  has  proved  a  success 
not  only  from  the  metallurgical  point  of  view 
by  furnishing  a  product  already  semi-smelted, 
from  which  little  or  no  flue-dust  results,  but 


also  by  efifecting  a  reduction  of  expenses,  thus 

turning  a  doubtful  proposition  into  a  profitable 

one.     After  experimenting  on  a  small  scale, 

the  present  type  of  pot  was  decided  upon. 

An  approximate  analysis  of  the  ore  is  as 

follows  : 

0/ 

SiO.,   25 

Fe 15"6 

A1,0. 3'8 

CaO  9 

Zn 11 

S     24-4 

Pb 6 

Cu Sb 

Ag 44oz.perton 

The  ore  is  crushed  to  pass  through  f  in.  mesh, 
and  is  then  mixed,  by  hand,  with  silicious  ma- 
terial and  lime  if  necessary.  This  charge,  con- 
taining about  5%  moisture,  is  delivered  to  bins 
above  the  pots.  It  was  found  by  experiment 
that  a  5%  moisture  content  gave  the  best  re- 
sults;  a  12%  content  made  it  impossible  to 
operate. 

The  type  of  pot,  hood,  and  carriage  are 
shown  in  the  accompanying  photographs.  The 
pot  is  8  ft.  8  in.  diam,  at  the  mouth,  with  the 
shell  2  in.  thick,  which  tapers  to  Is  in.  at  the 
bottom;  this  casting  weighs  11,000  lb.  The 
height  inside,  from  grate  to  rim,  is  3  ft.  6  in. 
From  the  top  of  the  shell  to  the  centre  of  the 
trunnion,  which  has  been  determined  as  2  in. 
below  the  centre  of  gravity  of  the  loaded  pots, 
is  24  in.  The  inside  surface  of  the  shell  has 
four  shoulders,  or  off'sets,  of  i  in.  eacn,  regu- 
larly spaced,  the  object  of  which  is  to  prevent 
the  creep  of  the  air-blast.  The  grate,  Ih,  in. 
thick,  is  slightly  arched,  on  an  11  ft.  radius, 
with  the  idea  of  better  resisting  the  load  ;  it  is 
divided  into  three  pieces,  the  centre  one  being 
the  largest,  with  side  pieces  of  equal  size.  It 
stands  14  in,  above  the  bottom  of  the  shell,  or 
inlet  of  the  blast,  resting  on  a  shoulder  1  in. 
wide  and  bolted  to  the  outside  of  the  pot.  The 
air-holes  are  1  in.  diam.  at  the  inlet,  and  fin. 
at  the  outlet,  spaced  2i  in.  between  centres  and 
a  like  distance,  vertically,  between  the  middle 
of  these  centres.  The  blast-pipe  is  6  in.  diam. 
and  so  arranged,  with  a  sleeve  connection,  that 
it  can  be  disconnected  when  the  pot  is  to  be 
raised.  The  hood,  covering  the  pot,  has  an 
inside  rim  that  fits  into  the  inside  of  the  shell. 
It  has  eight  openings,  seven  of  which  can  be 
closed  according  to  required  conditions.  The 
eighth  opening  is  to  allow  the  chute  from  the 
bin  to  enter,  and  it  cannot  be  closed.  The 
hood  is  raised  or  lowered  into  position  by  a 
hand-wheel  arranged  above  the  outlet  stack  of 


JULY,    1911 


63 


the  hood,  connected  with  a  rod  passing  through 
the  centre  of  the  frame.  From  this  stack, 
which  is  30  in.  diam.,  the  connection  leads  off 
to  the  discharge  chimney.  At  present  there 
is  no  flue-dust  chamber,  but  it  is  probable  that 
when  the  proposed  20  pots  are  in  operation 
one  will  be  erected.  The  pot  is  operated 
through  a  worm  gear.  The  track  on  which 
the  pot  runs  has  a  slight  downward  grade  to 
assist  in  moving  the  pot  forward  when  ready 
to  dump.  The  carriage  is  held  in  position, 
during  the  sintering  and  desulphurization,  by 
a  fin.  wire  rope,  controlled  by  a  hand-winch. 
The  capacity  of  the  pot  is  9  tons  of  crude  ore  ; 
the  runs  made  thus  far  indicate  that  11  tons 


Sufficient  time  is  then  allowed  until  it  appears 
red  before  the  first  charge — 300  lb. — is  thrown 
in  and  the  blast  slightly  increased.  Soon  after 
the  ore  has  been  spread  over,  using  an  ordi- 
nary garden  rake,  the  heavy  yellowish  sulphur 
fumes  begin  to  come  off  and  the  ore  crackles. 
When  the  mass  has  begun  to  turn  slightly 
red,  300  lb.  of  charge  i^  shovelled  in  and 
spread.  After  the  fourth  charge  has  been 
added,  making  a  total  of  1200  lb.,  and  the 
pressure  slightly  increased,  shovelling  is  dis- 
continued, all  the  charging  being  then  done 


.-1  Pot  after  Dischaige. 

can  be  charged.  The  pot  and  carriage,  com- 
plete, have  been  made  m  Lima  at  a  cost  of 
;^300,  which  seems  a  high  price.  Including 
freight  and  erection  of  hood  and  shed,  and  the 
pot  ready  to  run,  the  total  cost  was  ^"500. 

The  pot  is  charged,  at  6.45  a.m.,  with  shav- 
ings and  wood  to  a  depth  of  3  to  4  inches. 
This  is  set  on  fire  by  an  oil-dipped  rag,  which 
is  dragged  over  the  surface.  Once  fairly  ig- 
nited a  light  blast — about  i  oz. — is  turned  on, 
and  after  a  few  minutes  100  lb.  of  fine  coke 
(less  than  f  in.  size,  which  was  previously 
thrown  away)  is  spread  over  the  fire.  After 
the  coke  has  ignited  a  charge  of  100  lb.  of 
limestone  is  thrown  in  and  spread  out.  The 
limestone  prevents  the  bottom  of  the  charge 
from  becoming  too  hot  and  possibly  melting. 


Pol  ill  Operation.     Rakin<;  n  iliurge. 

throuf^li  the  chute  from  the  ore-bins.  Charges 
of  800  lb.  are  then  made,  with  increases  as 
the  wider  diameter  of  the  pot  is  reached.  The 
mass  tends  to  pack  in  the  pot  so  that  punch- 
ing, from  time  to  time,  is  necessary  to  allow 
the  gases  to  escape  and  to  permit  the  air  to 
penetrate.  It  is  noted  that  immediately  after 
a  charge  has  been  made,  the  pressure  rises 
one  to  two  ounces,  then  returning  to  the  nor- 
mal amount  as  soon  as  ignition  occurs.  .As 
the  charging  proceeds,  the  volatilization  of 
the  sulphur  takes  place  more  quickly  after 
spreading,  and  toward  the  end,  when  the  pot 
is  nearly  full,  the  sulphur  fumes  come  off 
almost  instantly.  With  the  increase  of  the 
contents  of  the  pot,  the  blast-pressure  in- 
creases, so  that  by  the  time  the  full  charge 


64 


THE    MINING    MAGAZINE 


has  been  made  (about  5.30  or  6  p.m.)  there  is 
5i  oz.  pressure.  The  surface  is  comfortably 
warm  and  where  holes  have  been  punched,  the 
interior  of  the  mass  shows  red-hot  and  the 
sintering  action  can  be  seen  ;  there  is  no 
blowing  away  of  the  light  particles  of  mineral. 
Bright  bluish  and  red  flames  are  emitted,  suc- 
ceeding the  heavy  yellow  fumes  of  sulphur 
and  the  bluish  white  sulphurous  gases  ;  the 
surface  of  the  mass  resembles  a  blacksmith's 
forge-fire.  There  is  a  slight  smell  of  sulphur 
gases,  usually  only  when  charging  this  being 
due  to  the  good  services  of  the  hood.  The 
shell  is  warm,  cooler  at  the  bottom  than  the 
top.  The  heaviest  part  of  the  operation  has 
now  been  completed  and  no  further  attention 
is  paid  to  the  pots  except  the  increase  of  pres- 
sure, every  few  hours,  which  reaches  a  maxi- 
mum of  9  to  10  oz.  by  5.30  a.m.,  at  which 
time  the  blast  is  cut  off.  At  present  an  old 
type  of  rotary  blower  is  used,  connected  by 
belt  with  a  rated  15  hp.  motor.  No  fumes 
are  apparently  given  off,  at  this  period,  while 
the  surface  of  the  mass  is  well  crusted,  and 
the  interior  is  red  hot,  but  agglomeration  is 
not  evident.  The  day-shift  of  12  hours  comes 
on  at  6  a.m.  and  prepares  to  dump  tne  pot. 
The  winch-rope  is  eased,  the  blast-connection 
is  lowered  out  of  place,  the  hood  raised  to 
clear  the  edge  of  the  shell,  and  the  carriage 
barred  to  get  it  into  motion.  When  the  pot 
is  ready  to  be  dumped,  having  been  moved 
out  from  the  hood,  the  worm  gear  is  set  in 
motion  until  the  pot  stands  at  an  angle  of 
about  97°,  the  entire  sintered  mass  slides  out 
on  a  mat  of  old  rails,  piled  on  the  ground,  thus 
slightly  breaking  the  fall  and  shattering  the 
mass.  There  is  no  barring  or  other  means 
necessary  to  induce  the  quick  discharge  of 
the  sintered  product.  Hardly  any  odour  of 
sulphur  gases,  and  no  fume,  is  given  off  ex- 
cept when  water  is  sprayed  to  hasten  the 
cooling ;  some  SOj  gas  is  generated,  but  not 
sufficient  to  be  annoying.  The  pot  is  scraped, 
on  the  sides  and  grate-plate,  and  then  revolved 
back  to  its  normal  position  and  hauled  to  its 
place,  under  the  hood,  by  means  of  the  winch. 
Usually  15  to  20  minutes  are  required  to  dis- 
charge both  pots,  from  the  beginning  of  the 
disconnection  until  the  pots  are  ready  to  be 
fired  once  more.  Three  men  and  a  foreman 
can  easily  attend  to  the  work.  The  sintered 
mass  is  cooler  at  the  bottom  than  the  top,  as 
is  to  be  expected,  the  former  place  being  the 
seat  of  more  recent  desulphurization  and  sin- 
tering. Sledging  is  necessary  to  break  up  the 
mass,  using  bars  to  ease  the  work.  The  two 
sintered  masses  can  be  broken  up  by  4  men 


in  8  hours  ;  the  amount  of  fine  resulting  is 
small  and  lumps  suitable  for  the  blast-furnace 
can  be  made.  The  texture  of  the  sinter  is 
porous  but  the  mass  holds  well  and  is  tough. 
There  is  apparently  but  little  flue-dust  made. 
A  slight  amount  of  lead  and  zinc  may  be  vola- 
tilized. The  desulphurization  amounts  to  75%. 
The  charge  suffers  a  reduction  of  about  10% 
in  weight. 

The  sinter  shows  the  following  analysis  : — 

% 

SiO. 28'6 

Fe 15'8 

AI.2O:, 3"9 

CaO 10'6 

Zn 10*8 

Cu 4'1 

S 6*1 

Pb 5-4 

Ag 48  oz.  per  ton. 

The  product  is  quite  self-fluxing  and  well 
suited  for  the  blast-furnace. 

The  advantages  of  the  sintering  process 
over  the  Brown  roasters  and  briquetting  seem 
to  be  as  follows  : 

1.  Less  labour  required  (possibly  50%) ; 

2.  Greater  desulphurization  ;    at  least  5% 

more ; 

3.  Better  smelting   product.     It  is   stated 

that  a  large  proportion  of  the  work  of 
the  blast-furnace  is  accomplished  in 
the  pots  and  that  the  blast-furnace  can 
smelt  40  to  50%  faster ; 

4.  Less  repairs ; 

5.  Less  interference  with  continuous  oper- 

ations ; 

6.  Less  room  for  plant  of  greater  capacity  ; 

7.  Decreased  flue-dust  in  the  blast-furnace ; 

8.  Less  coke  consumed  in  the  blast-furnace ; 

9.  Saving  in  flux  ; 

10.  Less  capital  invested  in  the  plant. 
The  present  blast-furnace  was  blown-in  on 
August  6,  1910.  It  is  a  standard  type  of 
American  water  -  jacketed  furnace,  all  the 
ironwork  having  been  made  in  Lima.  The 
inside  length,  at  the  tuyeres,  is  160  in.  and 
the  width  42  in. ;  the  tuyeres,  12  on  each  side, 
are  6  in.  diam.  and  spaced  12  in.  apart ;  there 
are  no  end-tuyeres.  From  the  centre  of  the 
tuyeres  to  the  charging-floor  the  height  is  10 
ft. ;  the  height  of  the  charge  is  usually  7  to  8 
ft.,  that  is  to  the  top  of  the  water-jackets,  of 
which  there  are  10,  three  to  each  side  and  two 
to  each  end,  with  a  34  in.  water-space.  There 
is  a  6-in.  bosh  to  the  upper  62  ft.  of  the  side 
jackets  ;  there  is  no  end-bosh.  The  slag-spout 
is  jacketed.  The  water  for  the  jackets  circu- 
lates automatically,  the  cold  water  entering  the 


JULY,    1911 


65 


bottom  of  the  jacket,  from  a  tank  above  the 
feed-floor,  and  the  warm  water  flowing  off 
from  the  top.  There  is  no  brickwork  inside 
the  furnace  except  in  the  crucible ;  the  feed- 
plate  castings  overlap  the  jackets.  The  cru- 
cible is  supported  on  a  solid  foundation  ;  the 
upper  part,  which  is  in  contact  with  the  matte, 
is  of  fire-brick,  resting  on  a  concrete  founda- 
tion, and  all  held  together  by  iron  plates  and 
tie-rods.  All  the  fire-brick  employed  is  of 
foreign  make.  The  depth  of  the  crucible  is 
12  in.;  the  slag  tap-holes — one  on  each  end 
of  the  furnace — are  16  in.  below  the  tuyeres, 
and  the  matte  tap-holes — one  to  each  side — 
are  12  in.  below  the  slag  tap-holes.     The  slag 


water  under  70  ft.  head,  lifts  40  ft.  It  is  used 
to  handle  matte,  slag,  flue-dust,  and  concen- 
trate from  the  tapping-floor  to  the  feed-floor 
{15' 5  ft.)  or  roaster  bedding-floor  (40  ft.)  All 
charging  to  the  furnace  is  done  by  hand,  the 
raw  ore,  briquettes,  sinter,  fluxes,  lime,  and 
coke  being  wheeled  to  the  charge-doors,  after 
having  been  weighed.  Coke  is  charged  first, 
then  ore,  sinter,  matte,  lime,  slag,  and  bri- 
quettes, through  the  charge-doors,  of  which 
there  are  four  to  a  side  ;  the  centre  ones  are 
opened  together  and  then  these  dropped  back 
into  place  and  the  end  ones  opened.  It  takes 
from  8  to  10  minutes  of  shovelling  to  a  charge, 
which  is  from  4500  to  6200  lb.  including  the 


SMELTER   FUME.     THE   CASAPALCA   SMELTER  IN   PERU. 


flows  away  continuously  into  a  settling-pot, 
the  overflow  from  which  drops  into  a  hole  in 
the  floor,  to  be  granulated  and  swept  away  by 
water  to  the  river.  The  slag  is  sampled  every 
half-hour,  while  samples  of  matte  are  taken 
every  four  hours.  A  two-foot  bustle-pipe  sup- 
plies the  air,  about  260  cu.  ft.  of  '  effective 
air '  (or  430  cu.  ft.  of  '  free  air ')  per  square  foot 
of  hearth-area  at  the  tuyere-level.  The  air- 
pressure  varies  from  11  to  15  oz.  The  top  of 
the  furnace  is  closed,  the  fume  passing  off^ 
through  a  straight  brick  flue  and  then  to  a 
dust-chamber,  thence  to  another  flue  connect- 
ing with  two  chimneys.  About  7%  flue-dust 
is  made.  The  total  length  of  the  dust-chamber 
is  about  200  feet. 

A    hydraulically    operated    elevator,   using 


coke.  From  45  to  60  charges  are  made  per 
shift,  the  higher  figure  obtaining  when  the 
furnace  is  running  well.  A  door  on  each  end 
of  the  furnace  is  used  when  removing  crusts. 
Coke  to  the  extent  of  9  to  ll/(^  of  the  charge 
is  fed.  It  contains  from  5  to  10%  ash  and  is 
of  Westphalian  make,  costing  delivered  at  the 
plant  £^  per  ton.  The  size  used  for  the  blast- 
furnace is  2i  in.  and  larger  ;  between  f  in.  and 
2i  in.  is  sent  to  the  lime-kilns  and  forges,  and 
less  than  f  in.  is  used  in  the  sintering  pots. 
The  SO.J  gas  present  is  not  overwhelming. 
About  80%  of  the  sulphur  in  the  charge  is 
volatilized.  About  10%  sulphur  is  carried  as 
an  average  of  the  ores,  sinter,  briquettes,  and 
matte.  There  is  usually  no  hot  top  although 
overfire  is,  of  necessity,  present.     An  approxi- 


66 


THE    MINING    MAGAZINE 


mate  idea  of  the  charges  run  can  be  obtained 
from  the  following  figures  : 

Febniarv  14,  1911.            6  a.m.  10  a.m. 

lb.  lb. 

Raw  ore 500  500 

Slag 400  400 

Lime 600  300 

Sinter 500  500 

Matte 400  400 

Briquettes 3000  2000 

5400  4100 

Coke 600  400 


6000       4500 

The  matte  from  the  6  a.m.  charge  ran  too 
low  in  silver  and  copper.  The  slag  fed  is 
added  to  make  smelting  easier.  The  matte 
fed  is  low  in  silver  (contracts  calling  for  over 
400  oz.  per  ton)  ;  it  tends  to  make  the  furnace 
run  faster. 

The  following  approximate  analyses  are  of 
interest : 

Raw  Ore  Roasted 

Natividad — Carmen    Sinter        Ore  Slag    Matte 

o/  o/  o/  o/  o/  o/ 

/o  /o  /o  /o  A>  /o 

SiO, 17'2  47'0  28"6  27'0  40"8  — 

Fe 24'0  4*9  15*8  18"0  20"9  14 

AI.Oh 1*4  2"4  3'9  2"1  5'5  — 

CaO trace  6'4  10'6  S'S  15"8  — 

Zn 3"4  9'6  10"8  9*2  10'3  6 

Pb —  7*2  5"4  10*3  —  6 

S 3r4  8*5  6T  7'6  —  22 

Cu 137  V6  4"1  6'4  0*3  50 

Mn —  rs  —  —  —  — 

oz.  oz.  oz.  oz.  oz.        oz. 

Silver ir3       52        48        50        IT  400 

The  blast-furnace  flue-dust  is  stated  to  be 
similar  in  composition  to  the  roasted  ore.  The 
concentration  is  10:  1.  The  matte  when  tap- 
ped runs  into  a  Kilker  matte-casting  car  ;  after 
cooling  it  is  dumped  in  front  of  a  crusher,  in 
which  the  larger  lumps  are  reduced  ;  268  bags 
of  matte  constitute  a  lot  of  20  tons,  the  capa- 
city of  a  freight-car.  From  12  to  20  tons  of 
matte  are  produced  daily  according  to  the 
running  of  the  furnace.  Samples  are  taken 
as  each  bag  is  weighed.  At  present  the  pro- 
duct is  shipped  to  Liverpool.  It  is  expected 
that  a  minimum  of  3,000,000  oz.  silver  and 
7,000,0001b.  copper  will  be  produced  annually, 
when  the  improvements  now  contemplated 
shall  have  been  made.  The  matte  contains 
only  traces  of  gold. 

The  following  statistics  will  prove  interest- 
ing: 


Silver  Copper 

Oz.  Long  tons 

1899 1,034,981  1,187 

1900 1,151,504  1,742 

1901 836,235  1,573 

1902 788,370  1,650 

1903 871,882  901 

1904 936,949  861 

1905 1,020,108  1,816 

1906 883,745  1,629 

\IqI]  1,804,023  2,902 

1909 1,094,859  1,125 

1910 1,877,321  2,235 

Total 12,299,977  17,627 

At  present  about  700  men  and  boys  (earn- 
ing from  0'60  to  1*20  centavos,  that  is,  1'2  to 
2'6  shillings,  per  day)  are  employed  in  the 
smelter.  Living  is  naturally  trying  at  such  a 
high  altitude,  and  is  often  made  more  so  owing 
to  the  settling  of  the  sulphurous  gases  in  the 
canyon.  The  rainy  season  is  disagreeable, 
but  in  clear  weather  the  climate  is  quite  in- 
vigorating ;  the  nights  are  cold.  Quarters  for 
the  white  stafif  have  been  made  comfortable. 
The  present  hospital  is  cramped  for  room,  but 
this  will  shortly  be  remedied. 

The  management  declines  to  give  data  as 
to  cost  during  the  present  period  of  re-con- 
struction, although  most  generous  in  supplying 
the  data  for  this  article. 


Rankin's  Process.  —  The  extraction  of 
metals  from  low-grade  sulphide  ores  is  a  prob- 
lem that  has  attracted  Colorado  chemists  and 
metallurgists  during  the  last  few  years.  We 
recently  referred  to  the  attempt  to  introduce 
the  chlorine  reaction.  We  are  now  informed 
that  the  nitric  acid  treatment  is  being  tried 
with  a  50-ton  plant  at  Lake  City,  operated 
according  to  the  patents  of  H.  D.  Rankin. 
The  action  of  nitric  acid  on  metallic  sul- 
phides is  to  produce  sulphates.  Owing  to  the 
cost  of  the  acid  and  the  difficulty  of  recover- 
ing it,  no  practical  application  has  ever  been 
possible.  Mr.  Rankin  has  devised  a  plant 
which  it  is  claimed  will  sulphatize  any  ore 
and  recover  the  nitrous  fumes  evolved  by  the 
reaction.  He  states  that  he  can  regenerate 
the  nitric  oxide  fumes  (NO)  to  nitric  per- 
oxide (NO2)  and  subsequently  by  means  of 
compressed  air  in  an  absorption  tower  obtain 
nitric  acid  once  more.  The  disadvantage  is 
that  with  plain  sulphides  other  processes  work 
better,  and  that  if  the  ore  is  complex  or  low- 
grade  it  will  be  impossible  to  recover  much  of 
the  acid. 


JULY,    1911 


67 


PRECIS  OF  TECHNOLOGY 

The  Giesecke  Ball-Mill. — The  South  African  Min- 
ing Journal  for  May  20  gives  a  short  account  of  the 
Giesecke  ball-mill,  which  is  made  in  Brunswick,  Ger- 
many, and  is  being  tried  at  the  Geldenhuis  Estate  on 
the  Rand  by  H.  Stadler  under  the  advice  of  the  in- 
ventor. The  mill  appears  to  act  on  the  same  prin- 
ciple as  that  invented  by  Hardinge,  but  instead  of 
being  made  conical  it  consists  of  two  cylinders  bolted 
end  to  end  with  no  intervening  screen  but  separated 
by  a  dividing  annular  rib  having  a  comparatively 
small  central  aperture.  Or  it  may  be  considered 
as  a  combination  of  a  ball-mill  for  coarse  grind- 
ing and  a  tube-mill  for  fine-grinding,  joined  together 
end  to  end,  with  a  small  circular  opening  be- 
tween them.  The  length  is  23  ft.  ;  the  length 
and  diameter  of  the  first  section  are  each  8  ft., 
and  the  other  part  is  15  ft.  long  and  6  ft.  diam.  The 
latter  part  is  divided  into  two  compartments  by  means 
of  a  similar  annular  rib.  In  the  three  compartments 
thus  made  steel  balls  are  used  for  crushing  and  grind- 
ing, and  their  size  is  graded  according  to  the  size  of 
the  ore  to  be  crushed.  In  the  first  compartment  with 
large  diameter  the  balls  are  4  in.  diam.  and  in  the 
third  they  are  Ih  in.  diam.  In  the  interior  of  the 
cylindrical  surface,  fall-plates  of  steel  are  placed. 
These  lift  the  balls  and  ore  as  the  mill  revolves  and 
provide  an  efficient  fall  for  them.  The  proportion  of 
water  to  ore  is  1  :  3.  The  eventual  discharge  is  regu- 
lated by  a  60-mesh  screen.  The  mill  is  intended  to 
displace  stamps  entirely  and  to  produce  a  fine  product 
of  sand  and  slime  in  one  operation.  Amalgamation 
will  not  be  used,  but  the  product  cyanided  direct. 

Tin  in  Rhodesia. — In  the  Rliodesian  Mining  Re- 
view for  May  24,  H.  B.  Maufe,  Director  of  the  Rho- 
desian  Geological  Survey,  gives  the  result  of  a  per- 
sonal examination  of  the  tin  deposits  recently  found 
in  the  Enterprise  gold-belt  of  Rhodesia,  situated  30 
miles  east  of  Salisbury.  The  cassiterite  is  found  in 
greisenized  pegmatite  dikes  vhich  are  intruded  through 
the  metamorphir  rocks  of  the  district.  These  rocks 
may  be  divided  into  three  groups  :  (1)  epidiorite  with 
intercalated  bands  of  schist  ;  (2)  '  ironstone  '  including 
limestone  ;  and  (3)  quartzites  and  conglomerates. 
They  have  been  intensely  compressed  by  forces  acting 
in  a  north  and  south  direction  and  so  folded  along  east 
and  west  lines.  The  general  dip  of  the  rocks  is  northerly. 
The  tin-bearing  dikes  pass  through  the  rocks  in  (1) 
and  (2)  and  their  general  trend  is  north  and  south. 
The  metamorphic  rocks  are  surrounded  on  the  north, 
east,  and  south,  by  granite  which  has  been  intruded 
into  them.  There  are  also  small  intrusive  bosses  of 
granite,  and  bosses  and  dikes  of  dolerite  and  norite. 
The  granite  is  a  medium-grained  biotite  variety,  and 
sometimes  contains  hornblende.  Normal  pegmatite 
dikes  are  abundant  near  the  edge  of  the  encircling 
granite,  and  they  extend  some  distance  into  the  meta- 
morphic rocks.  They  consist  of  an  intimate  growth 
of  while  felspar  and  grey  quartz  in  varying  degrees  of 
coarseness.  White  and  black  mica  are  occasionally 
present,  and  red  crystals  ot  garnet  are  in  some  places 
found  in  narrow  bands  or  small  bunches.  These  nor- 
mal pegmatite  dikes  have  not  so  far  been  found  to 
contain  cassiterite,  and  theoretically  are  not  likely  to 
do  so.  The  greisenized  pegmatite  dikes  are  not  in 
the  neighbourhood  of  the  encircling  granite,  but  some 
are  not  far  distant  from  the  small  intrusive  bosses. 
The  most  characteristic  feature  is  a  pink  mica  which 
was  supposed  by  the  prospectors  to  be  fluorspar.  An 
examination  showed   that   it  is  lepidolite  or  lithium 


mica,  which  is  often  associated  with  pegmatite  in 
other  parts  of  the  world.  The  dikes  consist  essen- 
tially of  quartz,  lepidolite,  and  felspar,  with  small 
amounts  of  fluorspar,  garnet,  topaz,  and  cassiterite. 
The  relative  proportion  of  these  constituents  varies 
greatly,  and  the  degree  of  coarseness  also  varies  a 
good  deal.  In  the  unaltered  parts  the  grey  quartz 
and  white  felspar  are  intimately  intergrown.  In  partly 
altered  parts  the  original  large  crystals  of  felspar  are 
separated  into  rounded  lumps  each  encircled  with  a 
zone  of  lepidolite  and  secondary  quartz.  Other  parts 
have  been  completely  altered  to  greisen  and  the 
original  felspar  is  absent.  Here  the  aggregate  of 
quartz  and  lepidolite  is  in  places  coarse  in  grain,  and 
in  other  places  so  fine  that  the  individual  crystals  are 
only  just  distinguishable  to  the  unaided  eye.  These 
fine-grained  portions  occasionally  exhibit  a  banded 
structure  owing  to  the  greater  abundance  of  the  mica. 
These  bands  are  in  wavy  lines,  suggesting  successive 
incursions  of  the  vapour  which  caused  the  alteration 
to  greisen  and  introduced  ths  tin.  The  cassiterite 
seldom  shows  crystalline  structure,  but  is  found  in 
the  form  of  irregular  black  grains  which  have  an  un- 
even fracture.  The  lustre  is  inclined  to  be  resinous 
rather  than  adamantine.  In  the  coarsely  crystalline 
portions  of  the  dikes,  the  cassiterite  occurs  in  grains 
up  to  one  inch  in  length  and  is  generally  associated 
with  the  quartz  ;  but  in  the  fine-grained  parts,  it  is 
more  evenly  disseminated  in  very  small  grains.  Mr. 
Maufe  proceeds  to  give  descriptions  of  a  number  of 
veins  that  have  been  prospected.  While  not  enthusi- 
astic as  to  their  extent  and  regularity  as  at  present 
determined,  he  considers  that  exploration  at  depth  is 
fully  warranted.  He  emphasizes  the  different  nature 
of  the  deposits  from  those  found  in  the  northern 
Transvaal.  It  is  also  notable  that  no  tourmaline  is 
found  in  the  greisenized  pegmatite,  though  it  occurs 
in  narrow  veins  which  traverse  the  schists  surrounding 
one  of  the  small  norite  bosses. 

Price  of  Glycerine. — Several  notices  have  appeared 
in  the  technical  Press  recently  announcing  that  the 
price  of  dynamite  and  allied  explosives  will  advance 
in  the  near  future  in  a  way  that  will  be  highly  incon- 
venient to  those  engaged  in  mining  operations,  owing 
to  the  increased  price  of  glycerine  which  is  the  base  of 
nitroglycerine  manufacture.  The  Times  of  June  13 
contains  a  timely  article  on  the  commercial  position 
of  glycerine  and  explains  the  reasons  for  the  enhanced 
price.  Glycerine  is  a  by-product  in  soap  manufac- 
ture ;  when  animal  and  vegetable  oils  are  treated  with 
alkali,  soap  and  glycerine  are  formed.  Except  for  its 
use  in  pharmaceutical  preparations,  glycerine  was  of 
small  commercial  value  until  nitro-glycerine  was  in- 
vented, and  nowadays  owing  to  the  restricted  circle  of 
explosive  makers  little  is  heard  of  it  as  an  ordinary 
market  commodity  The  'spent  lye'  left  behind  in 
the  manufacture  of  the  best  soaps  contains  about  9% 
of  glycerine.  The  relative  amount  of  glycerine  and 
soap  produced  by  the  reaction  varies  widely  according 
to  the  nature  of  the  raw  material  and  the  kind  of  soap 
produced.  Most  of  the  soap  makers  boil  the  lye  down 
to  produce  a  crude  glycerine  containing  80''o,  though 
some  of  the  producers  of  poor  quality  soap  throw  it 
away.  Only  a  few  of  the  large  houses  make  a  refined 
product  ;  the  others  either  sell  the  crude  to  the  bigger 
firms,  to  the  limited  number  of  explosive  manufac- 
turers who  undertake  refining,  Nobels  being  the  chief, 
or  to  merchants  who  buy  for  .\merica.  The  British 
Government  cordite  works  do  not  refine,  but  buy 
mostly  from  Nobels.  At  the  beginning  of  1907,  crude 
glycerine  was  worth  /28.  10s.  per  ton,  and  refined  ;^50 
per  ton.     By  the  end  of  the  year  crude  had  advanced 


68 


THE     MINING     MAGAZINE 


to  £6?,  and  refined  to  /105  per  ton.  The  cause  is  due 
chiefly  to  the  advance  in  the  price  of  oils  and  fats. 
The  soap  maker  has  found  it  impossible,  or  at  least 
injudicious,  to  recoup  himself  by  increasing  the  price 
of  soap,  owing  to  its  being  a  national  commodity 
necessary  to  the  poorest  classes,  so  he  has  had  to  turn 
his  attention  to  the  other  outlet  of  his  products.  It  is 
interesting  to  note  that  the  chief  reason  for  the  advance 
in  the  price  of  fats  and  oils  is  their  increasing  use  in 
the  manufacture  of  margarine.  Some  of  the  largest 
soap  makers  have  found  it  necessary  to  protect  them- 
selves by  becoming  their  own  producers  of  vegetable 
oils.  Taking  all  these  facts  into  consideration  it  is 
obvious  that  the  price  of  explosives  will,  unfortunately 
for  the  mines,  continue  to  advance. 

Temperatures  at  St.  John  del  Rey.— As  has  already 
been  recorded  in  our  June  number,  and  in  the  Com- 
pany Reports  on  another  page  of  the  present  issue, 
the  Morro  Velho  gold  mine  in  Brazil  that  has  been 
worked  continuously  for  80  years  by  the  St.  John  del 
Rey  Mining  Co.  is  the  deepest  in  the  world.     Level 
No.  17  which  is  now  being  developed  is  4600  ft.  verti- 
cally below  the  adit  or  4920  ft.  below   the  surface. 
The  lode  dips  at  approximately  45°  and  as  shown  in 
the   illustration   given    last  month   operations  below 
Level  8  are  conducted  by  means  of  underground  ver- 
tical shafts,  named  '  E  '  and  '  F,'  each  1200  ft.  deep, 
and  extending  from  Levels  8  to  12  and  12  to  16  re- 
spectively.    Level  16  at  4300  ft.  below  adit  has  now 
been  driven  nearly  far  enough  for  the  commencement 
of  another  shaft,   '  G.'     The  levels  are  300  ft.  apart. 
As  the  lode  shows  every  sign  of  persistence,  George 
Chalmers,  the  manager,  is  making  arrangements  for 
work  to  be  continued  to  a  depth  of  6500  ft.      Efficient 
ventilation  for  the  purpose  of  reducing  the  tempera- 
ture of  the  air  and  rock  is,  of  course,  of  prime  import- 
ance.    Mr.  Chalmers  gives  much  interesting  detail  in 
connection  with  his  investigations  on  this  subject  in 
his  report  on  the  progress  of  the  mine  during  the  year 
ended  February  last.     Before  the  '  F  '  shaft  was  com- 
pleted the  workings  on  the  14th  and  15th  levels  were 
unpleasantly  hot,  but  directly  through  connection  was 
made  the  conditions  rapidly  improved.  At  the  present 
time  the  ventilation  is  effected  by  a  Capell  fan  driven 
by  a  80  hp.  motor,  at  the  surface,  together  with  some 
auxiliary  fans  underground.     It  has  now  been  decided 
to  provide  two  more  fans,  only  one  of  which  will  be 
put  in  commission  at  first,  and  driven  by  a  150  hp. 
motor.     As  the  depth  of  the  workings  increases  the 
second  will  be  started  with  a  300  hp.  motor,  and  later 
the  first  fan  will  be  driven  by  a  300  hp.  motor.     The 
accompanying  chart  gives  a  diagrammatic  record  of 
the  results  of  investigations.      During  the  four  hottest 
months  of  the  year,  November  to  March,  temperature 
readings  were  regularly  taken  of  the  air  at  each  level 
and  of  the  rock  at  the  end  of  10  ft.  holes.     The  mean 
of  the  air  temperatures  is  shown  in  the  line  P,  and  of 
the  rock  temperatures  in  the  line  Q.      It  will  be  seen 
that  from  adit  to  Level  8  the  air  temperature  is  slightly 
greater  than  that  of  the  rock.     Thereafter  the  rock 
temperature  becomes  greater.     From  Level  14  to  17 
both  advance  more  rapidly,  a  fact  due  to  these  levels 
having  been  open  only  a  comparatively  short  time, 
and  the  rock  having  been  exposed  to  the  cooling  effect 
of  only  a  small  quantity  of  air.     The  figures  relating 
to  the  original  temperatures  when  the  rock  was  first 
exposed  at  various  points  and  the  subsequent  fall  in 
the  temperatures  are  of  considerable  value  in  helping 
to  forecast  future  conditions.     On  Level  14  in  1906, 
when  it  had  just  been  reached,  the  rock  temperature 
was  98°F  as  marked  at  A,  and  the  air  temperature 
95°F  marked  at  B.     As  soon  as  the  level  was  con- 


nected with  the  ventilating  system  the  rock  tempera- 
ture fell  to  924°F  marked  at  C,  and  that  of  the  air  to 
87^°F  marked  at  D.  With  the  more  efficient  system 
of  ventilation  now  introduced  it  may  be  assumed  that 
the  lines  P  and  Q  will  not  curve  to  the  right,  but  will 
more  or  less  follow  their  straight  course  from  adit  to 
Level  8.  The  probable  increase  in  the  air  temperature 
may  therefore  be  expected  to  follow  the  line  R.  This 
line  cuts  the  abscissa  representing  a  depth  of  6500  ft. 
at  a  temperature  of  95°F,  which  is  practically  the 
temperature  of  the  workings  at  Level  16  at  the  time 
of  writing,  so  it  may  be  supposed  that  with  efficient 
ventilation  operations  can  be  conducted  at  this  depth. 
The  rock  temperatures  at  the  time  of  opening  are  esti- 
mated on  the  chart  by  drawing  a  line  S  through  the 
two  points  A  and  E  which,  as  far  as  can  be  exactly" 
ascertained  by  means  of  long  bore-holes,  represent 
the  actual  rock  temperatures  at  Levels  14  and  17  be- 
fore developments  were  begun.  At  6500  ft.  the  tem- 
perature at  which  the  rock  is  opened  is  in  this  way 
shown  to  be  117°F.  If  as  already  calculated  the  air 
temperature  can  be  reduced  by  ventilation  to  95°F,  it 
would  appear  that  work  could  be  continued  to  an  even 
greater  depth  than  6500  ft. 

Goldfield  Consolidated  Mill. — A  particularly  valu- 
able series  of  articles  is  now  appearing  in  the  Mining 
and   Scientific   Press   describing  in  full  detail    the 
operation  of  the  mill  and  extraction  plant  erected  two 
years  ago  at  the  Goldfield  Consolidated  mine,  Nevada. 
The  first  appeared  in  the  issue  of  May  6.     They  have 
been  written  by  J.   W.    Hutchinson,   the  director  of 
metallurgical    operations.     The   ore    is   an    enriched 
dacite,  and  the  workings  are  now  in  the  sulphide  zone 
where  the  ore  becomes  much  softer.     The  gold  is  in 
a  fine  state  of  division  and  the  whole  of  the  ore  is 
slimed  to  200-mesh  before  any  extraction  is  attempted. 
The  pulp  is  then  sent  to  Deisler  slime  tables.     The 
concentrate  is  passed  over  amalgamation  plates  and 
treated  in  Pachuca  vats  and  Kelly  presses,  while  the 
tailing  is  sent  to  the  main  cyanide  plant  which  consists 
of  Pachuca  vats.  Butters  filters,  and  Merrill  precipita- 
tion plant.     The  value  of  articles  such  as  th-^se  de- 
pends on  the  wealth  of  detail,  and  naturally  they  do 
not  lend   themselves  to  the  purposes  of   the   precis 
w  riter.     There  is,  however,  one  aspect  of  the  crushing 
problem    that    may    be    referred    to  in   this  column. 
When  the  plant  was  erected,  100  stamps  each  weigh- 
ing  1050  lb.   were  provided.      These  crushed  to   12- 
mesh,  and   subsequent   reduction    to    200-mesh    was 
effected  in   10  tube-mills.       Six   months  afterwards, 
when  the  old  Combination  mill  was  put  out  of  com- 
mission, it  was  decided  to  increase  the  capacity  of  the 
new  mill  from  600  tons  to  850  tons  per  day,  and  in 
order  to  do  this  40  additional  stamps  and  3  tube-mills 
were  to  be  added.     Additional   buildings,   ore  bins, 
etc.,  would  of  course  be  necessary,  and  the  total  cost 
of  the  extension  was  estimated  at  !|175,000,  while  the 
time  occupied  in  the  construction  and  erection  would 
be  6  months.     Mr.  Hutchinson,  however,  was  not  in 
favour  of  this  scheme,  and  eventually  a  different  plan 
was  followed,  namely,  the  placing  of  six  6  ft.  Chilean 
mills  between  the  stamps  and  tube-mills.  The  battery 
screens  were  altered  to  4-mesh,  and  16-mesh  screens 
were  put  in  the  Chileans.     In  practice  it  is  found  that 
80%  passing  through  the  Chilean  screens  is  less  than 
30-mesh,  and  in  fact  30%  will  pass  200-mesh.     The 
cost  of  the  new  installation  including  24  new  slime- 
tables  was  only  175,000  and  it  was  ready  for  work  in 
less  than  3  months.     Mr.  Hutchinson  enters  into  de- 
tails as  to  the  amount  crushed  by  the  old  and  new 
systems,  and  the  relative  power   required,    and    dis- 
cusses the  advantage  obtained  by  the  new  arrange- 


JULY,    1911 


69 


DEGREES  ' 

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TEMPERATURES  AT  THE  MORRO  VELHO  MINE  OF  THE  ST.  JOHS  PEL  IlKY  MIMSO  CO. 


70 


THE    MINING.  MAGAZINE 


ment  which  permits  the  ore  when  fine  enough  to  be 
removed  from  further  treatment.  To  those  who  have 
not  hitherto  followed  the  metallurgical  treatment  at 
this  mine,  the  bulletin  describing  the  plant  issued  by 
the  Allis-Chalmers  Co.  will  prove  of  explanatory 
value.  We  would  also  add  that  the  articles  have 
been  republished  in  pamphlet  form. 

Chilean  Mills  versus  Rolls.— In  Metallurgical  and 
Chemical  Engineenng  for  June,  Rudolf  Gahl  de- 
scribes experiments  undertaken  at  the  concentration 
plant  of  the  Detroit  Copper  Company  at  Morenci, 
Arizona,  with  a  view  of  ascertaining  the  relative  effi- 
ciencies of  Chilean  mills  and  high-speed  rolls  when 
used  for  the  purpose  of  re-grinding  jig  tailing.  He 
does  not  discuss  the  question  from  the  point  of  view 
of  power  consumed  or  of  keeping  the  two  machines 
in  good  working  order,  but  confines  himself  to  the 
study  of  the  comparative  amount  of  slime  produced 
and  the  percentage  of  copper  recovered.  In  view  of 
the  facts  that  the  Utah  Copper  Co.  has  a  large  instal- 
lation of  Chilean  mills  for  re-grinding  jig  tailing  and 
is  about  to  apply  a  form  of  stage-crushing  to  them, 
and  also  that  at  the  Miami  copper  mine,  Chilean 
mills  are  used  in  one  unit  and  high-speed  rolls  in  the 
other,  Mr.  Gahl's  paper  is  of  special  interest.  His 
tests  were  made  with  a  5  ft.  Chilean  mill  run  at  136 
r.p.m.  and  with  rolls  36  in.  diam.,  15  in.  long,  and 
running  at  140  r  p  m.  The  oversize  from  the  rolls 
was  as  is  the  usual  practice  returned  to  them  The 
first  test  was  on  material  that  passed  through  round 
holes  7  mm.  diam.  but  not  through  5  mm.  holes,  and 
the  discharge  screens  of  both  plants  had  2h  mm.  holes. 
The  analysis  of  the  results  is  given  as  follows  : 


Percentafje 

Mesh 

Rolls 

Chilean  Mills 

-1-20 

231 

11  0 

20  to  30 

160 

70 

30  to  100 

234 

212 

100  to  200 

6-6 

93 

-200 

309 

31-5 

It  will  be  seen  that  the  Chilean  mill  made  a  much 
finer  product  and  a  great  deal  more  slime.  In  test 
No.  2  the  material  treated  was  between  5  and  2imm. 
with  the  same  discharge  screens  as  No.  1,  and  the 
general  result  was  much  the  same.  He  then  pro- 
ceeded to  ascertain  whether  the  copper  mineral  was 
as  efficiently  freed  from  the  gangue  in  the  rolls  as  in 
the  mills,  by  treating  each  size  produced  by  the  two 
machines,  on  Wilflev  tables  up  to  200  mesh,  and  the 
slime  by  panning.  It  was  found  that  more  copper 
was  lost  in  the  Wilfley  tailings  from  the  roll  product 
than  from  the  Chilean  mill  product,  and  that  though 
more  slime  was  made  in  the  mill,  the  total  recovery  was 
slightly  greater  in  the  mill  than  bv  the  rolls.  A  third 
test  was  made  with  5  to  2h,  mm.  material,  with  1  mm. 
round  hole  screens  on  the  Chilean  mill  and  wire  mesh 
screens  with  aperture  079  mm.  in  connection  with  the 
rolls.  The  result  obtained  was  that  the  eventual  re- 
covery of  copper  was  practically  the  same  in  both 
cases,  the  mill  losing  more  in  the  slime  and  the  rolls 
in  the  sand.  If  no  further  facts  in  connection  with 
the  general  concentration  problem  are  taken  into  con- 
sideration, the  mill  would  be  the  best  machine  to  use, 
because  it  is  simpler  and  easier  to  keep  in  efficient 
working  order.     If  however  any  subsequent  regrinding 


of  the  coarse  pulp  from  the  mill  or  rolls  is  contem- 
plated, the  decision  in  favour  of  the  mill  is  not  neces- 
sarily final,  because  the  coarse  product  of  the  rolls  con- 
tains more  copper  that  can  be  freed  by  further  re- 
grinding.  The  author  subsequently  made  experiments 
with  Chilean  mills  with  a  view  to  reducing  the  amount 
of  slime  produced,  and  endeavoured  to  reproduce  the 
conditions  obtaining  with  rolls,  whereby  the  material 
when  ground  sufficiently  fine  is  immediately  removed. 
He  fitted  the  mill  with  a  3  mm.  slotted  screen  when 
treating  5  to  2h  mm.  material,  and  passed  the  discharge 
to  a  wire  screen  with  0  79  mm.  aperture,  the  over- 
size being  returned  to  the  mill.  He  does  not  give  full 
details  of  the  results  in  his  paper,  but  his  conclusion 
is  that  by  this  re-arrangement  of  the  work  of  the 
Chilean  mill  the  proportion  of  slime  can  be  reduced 
to  approximately  the  same  as  that  produced  by  the 
rolls.  By  such  an  arrangement  the  advantages  of  the 
rolls  frorri  the  point  of  view  of  slime  production  would 
be  gained  by  the  Chilean  mill  while  retaining  those 
already  possessed  by  it.  He  wishes  it  to  be  clearly 
understood  that  his  comparison  of  the  two  machines 
is  limited  to  the  sizes  of  material  mentioned,  for  with 
coarser  material  thesuperiorityof  rollsisunquestioned. 

Duralumin. — This  metal  has  been  prominently  be- 
fore the  public  recently  because  Vickers  Sons  & 
Maxim  have  used  it  in  the  construction  of  the  latest 
airship  built  for  the  British  War  Office.  It  is  made 
at  Duren  in  Khenish  Prussia,  and  was  described  in 
Elektrotcchnische  Zeitschrift  for  April  27.  It  is 
composed  chiefly  of  aluminium  with  an  admixture  of 
\%  magnesium,  3^  to  5^%  copper,  and  0'5  to  08% 
manganese.  It  is  claimed  that  these  additions  greatly 
increase  the  strength,  hardness,  ductility,  and  resis- 
tance to  chemical  attack.  The  speci6c  gravity  varies 
between  2  75  and  284,  and  the  melting  point  is  650''C. 
The  electric  conductivity  is  less  than  that  of  pure  alu- 
minium. If  heated  above  150^C,  its  strength  rapidly 
diminishes,  so  it  is  of  no  value  in  power  or  chemical 
plants.  It  is  undesirable  to  use  it  in  contact  with 
copper  or  brass,  so  rivets  must  be  made  of  the  same 
metal  or  of  iron. 

Efficiency  of  Suction  Pumps. — Mining  engineers 
sometimes  forget  that  the  altitude  above  the  sea  and 
the  temperature  of  the  water  have  an  important  bear- 
ing on  the  height  to  which  water  can  be  elevated  by 
suction,  and  are  puzzled  at  the  poor  results  obtained 
at  high  elevations  or  when  the  sump  water  is  made 
hot  by  exhaust  steam  from  underground  pumping  or 
hauling  plants.  J.  T.  Beard  contributes  useful  infor- 
mation on  this  subject  in  Mines  and  Minerals  for 
June.  The  elementary  principle  is  that  water,  mer- 
cury, or  other  liquid  can  be  sustained  in  a  tube  with  a 
closed  top  to  such  a  height  that  the  column  is  equal 
in  weight  to  a  similar  column  of  the  atmosphere. 
The  pressure  of  the  atmosphere  at  normal  tempera- 
ture at  sea-level  is  approximately  14  7  lb.  per  sq.  in. 
A  cubic  inch  of  mercury  weighs  0  49  lb.  and  a  cubic 
inch  of  water  003608  lb.,  so  that  the  height  of  the 
respective  columns  will  be  30  in.  and  34  ft.  As  the 
altitude  above  sea-level  increases,  so  does  the  height 
of  the  column  that  can  be  raised  decrease;  the  figures 
for  the  various  altitudes  are  given  in  standard  refer- 
ence books.  The  point  which  is  usually  neglected  is 
the  vapour  tension  above  the  column  due  to  vola- 
tilization. .At  the  normal  temperature  62°F  the  amount 
of  water  volatilized  and  filling  what  would  otherwise 
be  the  vacuum  is  comparatively  small  ;  the  vapour 
tension  is  0273  lb.  per  square  inch,  which  reduces 
the  column  of  water  supported  to  33  3  ft.  If  the  water 
is  heated  the  vapour  tension  greatly  increases.  At 
150^F  the  tension  is  37  lb.,  so  that  the  height  of  the 


JULY,    1911 


71 


column  of  water  raised  is  only  25  ft.  ;  while  at  180°F 
the  tension  is  7J  lb. ,  and  the  column  of  water  raised  is 
only  half  what  it  would  be  at  normal  temperature.  In 
actual  practice  there  is  a  third  factor  to  be  considered, 
that  is,  items  relating  to  the  mechanical  efficiency 
of  the  plant,  such  as  leakage,  friction,  and  the 
presence  of  air  in  the  water  ;  Mr.  Beard  considers 
that  25%  must  be  deducted  for  these  causes.  Taking 
the  three  factors  together  he  has  worked  out  the  accom- 
panying useful  table,  which  is  so  complete  that  it  re- 
quires no  further  explanation.  It  will  be  seen  that  at 
an  altitude  of  10,000  ft.,  water  at  180°F  can  be  raised 
less  than  5  ft.  by  suction.  The  figures  in  the  table 
refer  to  vertical  pipes  ;  if  the  pipes  are  inclined  the 
allowance  for  friction  must  be  increased.  Mr.  Beard's 
table  is  equally  applicable  to  siphons. 


the  gold  favours  neither  acid  nor  basic  rocks,  but  that 
the  silver  is  more  plentiful  in  basic.  As  regards  sedi- 
mentary rocks  his  recorded  figures  point  to  an  average 
content  of  15  milligrammes  or  1  cent  per  ton  and  show 
that  the  coarser  the  texture  the  greater  the  content. 
The  sea- water  is  estimated  to  contain  28  milligrammes. 
Assuming  that  the  contents  of  sea-water  have  been 
derived  from  the  destruction  of  igneous  rocks,  Mr. 
Lincoln  works  backward  and  deduces  from  the  above 
figures  for  sedimentary  rocks  and  sea-water  that  the 
original  content  of  the  igneous  rocks  must  have  been 
55  milligrammes  of  gold  per  ton,  a  figure  not  far  off 
his  average  of  recorded  investigations.  This  result 
agrees  substantially  with  De  Launay's  generaliza- 
tions. The  author  proceeds  to  show  that  no  mag- 
matic  segregation  of  primary  gold  in    igneous  rock 


Safe  Suction-Head  for   Pumps  at  Different  Elevations  and 
Various  Temperatures  of  Water. 


Elevation 

Above 
Sea  Level 

Feet 

Atmospheric 
Pressure 

Pounds 

per 
Square 

Inch 

Barometric 
Pressure 

Inches 
Mercury 

Temperature  of  Water  Raised  in  Dag 
Fahrenheit 

rees 

60 

c 

90 

120 

150 

180 

jafe  Suction-Head  for  Pump  in  Feet 

10,000 

10107 

20582 

170  • 

16-4 

14-7 

113 

4-7 

5,000 

12224 

24  890 

205 

19-9 

182 

14-8 

8-2 

4,000 

12-689 

25-837 

21-5 

209 

192 

158 

92 

3.000 

13169 

26813 

224 

218 

202 

168 

10-2 

2,000 

13665 

27-824 

23-2 

226 

210 

17-6 

110 

1,000 

14174 

28861 

24  1 

235 

219 

185 

119 

Sea  level 

14  696 

29 -925 

250 

24-4 

228 

194 

128 

iter  vapour  at 
)eratures 

Lb.  per  Sq.  In. 

0255 

0  693 

1683 

3 -706 

7  500 

Tension  of  w< 
various  temf 

Inches  Mercury 

0518 

1410 

3-427 

7-547 

15-272 

The  Distribution  of  Gold. — Economic  Geology  for 
May  1911  contains  a  valuable  article  by  F.  C.  Lincoln 
entitled  '  Certain  Natural  Associations  of  Gold.'  The 
paper  is  divided  into  two  parts,  the  first  dealing  with 
the  recorded  occurrences  of  primary  gold  in  rocks  and 
waters,  and  the  second  describing  the  association  of 
gold  with  various  minerals.  The  first  part  collects 
together  the  result  of  the  author's  and  other  investi- 
gators' enquiries  into  the  presence  of  primary  gold  in 
rocks  as  distinct  from  lodes  and  veins.  He  tabulates 
the  results,  dividing  the  rocks  into  igneous,  metamor- 
phic,  and  sedimentary,  and  gives  the  figures  for  the 
gold  contained  in  various  kinds  of  waters.  He  in- 
cludes also  records  of  the  presence  of  gold  in  minerals 
of  organic  origin,  such  as  coal,  and  in  living  organisms. 
In  interpreting  these  records  he  prefaces  the  warning 
that  the  method  of  assaying  rocks  for  minute  traces  of 
gold  is  of  importance,  because  the  reagent  employed 
is  as  likely  to  contain  gold  and  silver  as  the  rocks,  a 
circumstance  pointed  out  in  this  magazine  recently  ; 
also  that  many  investigators  have  taken  their  samples 
too  near  a  vein,  not  fully  appreciating  the  distance  to 
which  secondary  impregnations  may  extend.  In  the 
records  quoted  by  the  author  the  contents  vary  widely, 
the  figures  for  igneous  rocks  ranging  from  nothing  to 
5  grammes  per  metric  ton.  After  careful  considera- 
tion of  the  various  cases  he  takes  the  average  gold 
content  of  igneous  rocks  at  62  milligrammes  per  met- 
ric ton,  that  is,  one  grain  per  ton  of  2000  lb.,  and  the 
silver  content  at  3741  milligrammes  per  metric  ton  or 
24  dwt.  per  ton  of  2000  lb.     He  also  concludes  that 


has  ever  taken  place,  and  that  no  placers  of  commer- 
cial value  have  ever  been  produced  from  the  primary 
contents  of  eroded  igneous  rocks.  These  and  other 
occurrences  of  gold  are  discussed  in  detail  and  the 
facts  are  marshalled  in  such  a  way  as  to  lead  to  a 
theory  of  the  origin  of  auriferous  lodes,  thus  :  (/) 
gold  has  not  been  found  in  volcanic  emanations  and 
its  presence  in  plutonic  emanations  has  only  been  in- 
ferred ;  (2)  gold  has  been  found  in  the  circulating 
waters  of  the  earth 's  crust ;  (3)  there  are  a  great  num- 
ber of  valuable  deposits  of  primary  gold  in  geologi- 
cally young  conglomerates,  several  in  geologically 
old  conglomerates,  and  two  known  cases  in  metamor- 
phic  rocks  ;  (-/)  there  are  none  in  igneous  rocks.  Pre- 
sented in  this  order  the  facts  suggest  that  the  gold  of 
many  lodes  may  have  been  deri\ed  by  circulating 
waters  from  buried  placers,  and  Mr.  Lincoln  enumer- 
ates the  varying  .sources  in  order  of  importance  as 
follows  ;  (7)  depressed  beds  of  open-textured  sedimen- 
taries,  (2)  depressed  bed's  of  open-textured  tufaceous 
rocks,  (J)  fractured  older  lodes,  (4)  fractured  compact 
igneous  rocks.  (J)  fractured  compact  sedimentary 
rocks.  As  a  specific  case  he  considers  that  the  Ter- 
tiary lodes  owe  their  gold  mainly  to  the  leaching  of 
pre-Cambrian  placers  by  magmatic  or  meteoric  waters 
put  in  circulation  by  the  intrusion  of  the  andesite. 
The  above  is  a  mere  outline  of  an  interesting  paper 
that  should  be  studied  in  detail. 

As  regards  the  second  part,  the  association  of  gold 
with  various  minerals,  the  collection  of  data  has  been 
done   with  equal  care.      He  shows  that  in  sedimen- 


1—6 


72 


THE    MINING    MAGAZINE 


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JULY,    1911 


73 


tary  rocks  gold  is  frequently  associated  with  the 
heavier  and  less  soluble  constituents,  and  in  meta- 
morphic  rocks  with  magnetite  ;  also  that  the  gold  in 
igneous,  metamorphic,  and  sedimentary  rocks  is  in 
the  form  of  native  gold  in  grains.  In  veins  gold  is 
found  associated  with  at  least  173  mineral  species, 
but  of  these  there  are  only  a  few  which  when  present 
with  the  gold  are  more  apt  than  not  to  contain  inter- 
grown  and  disseminated  gold.  These  are  quartz, 
opal,  roscoelite,  magnesite,  pyrite,  galena,  hessite, 
altaite,  calaverite,  tetradymite,  selenium  minerals, 
lollingite,  arsenopyrite,  bismithinite,  aikinite,  and  bis- 
muth. It  will  be  seen  that  these  are  either  non- 
metallic  minerals,  the  two  common  sulphides,  or 
contain  bismuth,  arsenic,  selenium,  or  tellurium. 
The  latter  four  substances  are  closely  associated  in 
the  periodic  system  and  widely  removed  from  gold. 

Treatment  Plant  at  the  Dome  Mine,  Porcupine. — 
The  Mining  and  Scientific  Press  for  May  20  gives 
the  flow-sheet  of  the  plant  designed  by  the  Merrill 
Metallurgical  Co.,  of  San  Francisco,  for  the  Dome 
Mines  Co.,  at  Porcupine,  Ontario.  The  plants  hither- 
to erected  in  this  new  gold  mining  district  have 
been  of  an  experimental  or  makeshift  nature,  and 
that  now  being  erected  at  the  Dome  is  the  first 
of  permanent  importance.  The  ore  raised  from  the 
mine  at  (7)  goes  to  gyratory  crushers  (2)  and  (J),  and 
then  by  belt  (4)  to  the  stamp-mill  bin  (5).  There  are  four 
batteries  (6)  of  10  stamps  each,  the  stamps  weighing 
1230  lb.  and  dropping  102  times  per  minute.  The 
pulp,  after  passing  over  amalgamating  plates  (7),  goes 
to  Dorr  classifiers  [8),  from  which  the  fine  goes  to 
secondary  amalgamating  plates  (70)  and  the  coarse  to 
tube-mills  (9),  the  discharge  from  which  is  returned 
by  means  of  Frenier  pumps  to  the  Dorr  classifiers. 
The  tailing  goes  through  concentrating  cones  {12)  and 
Dorr  thickeners  (13),  the  water  being  returned  by  the 
pump  (/ 6),  and  the  pulp  sent  to  four  continuous  agitator- 
vats  measuring  8  by  40  ft.  ;  thence  to  Dorr  thickeners 
(18).  The  overflow  from  the  latter  goes  to  the  tank 
(19)  and  thence  through  the  Merrill  clarifying  press 
(20),  while  the  thick  pulp  goes  to  Merrill  slime  presses 
(21).  The  strong  barren-solution  tank  is  at  (27),  and 
the  weak  barren-solution  tank  at  (33).  The  strong- 
solution  precipitating-vats  are  shown  at  (22)  and  the 
weak-solution  precipitating-vats  at  (28),  and  the  cor- 
responding Merrill  precipitation-presses  at  (24)  and 
(30).  (23),  (29),  (26),  (32)  and  (36)  are  pumps';  (25) 
and  (31)  are  barren-solution  sumps  ;  flushing  w  ater  for 
the  filter  presses  is  obtained  from  (37),  and  the  water 
is  recovered  in  Dorr  thickeners  (34). 

CURRENT    LITERATURE 

Mine  Book-keeping. — In  the  Mining  and  Scienti- 
fic Press  for  June  3,  K.  C.  Parrish  gives  a  system  for 
book-keeping  at  prospects  and  small  mines,  that  can 
easily  be  amplified  as  the  work  increases. 

Dust  Collector  for  Mines. — The  Iron  and  Coal 
Trades  Review  for  May  26  describes  an  apparatus 
for  collecting  dust  from  the  floors  and  timbers  of 
mines.  A  tank  travels  on  the  rails,  and  a  suction 
hosepipe  and  nozzle  held  and  directed  by  boys  draw 
in  the  dust.  The  suction  may  be  created  by  a  fan 
driven  electrically  or  by  means  of  a  jet  of  compressed 
air  acting  as  an  ejector. 

Prospecting  for  Iron  Deposits. — In  the  Engineer- 
ing and  Mining  Joiirnalior  ]une  10,  R.  S.  Archibald 
discusses  the  method  used  in  the  Lake  Superior  iron 
region  of  prospecting  for  ore  deposits. 

Tippett's  Stope  Drill  — In  the  South  African  Min- 
ing Journal  for  May  6,  E.  M.  Weston  gives  some  in- 


formation about  the  so-called  "  New  "  drill  invented 
by  E.  Tippett,  an  Australian  engineer  employed  on 
the  Rand.  It  is  a  small  drill  intended  specially  for 
sinking  shafts  and  winzes.  The  holes  are  kept  full  of 
water  and  the  hydraulic  pressure  helps  the  return  of 
the  drill  at  the  back  stroke  and  removes  the  broken 
rock  rapidly.  This  arrangement  obviates  one  of  the 
drawbacks  of  the  hammer  drill.  Additional  informa- 
tion will  be  awaited  with  interest. 

Crosse's  Fine-Grinder. — The  South  African  Min- 
"'5  Journal  for  May  27  contains  a  description  of 
A.  F.  Crosse's  grinding  machine  for  reducing  pyrite 
concentrate  to  slime. 

McLeod  Concentrator.— T^e  Mining  World  (Chic- 
ago) for  June  10  describes  McLeod's  concentrating 
table  which  has  been  used  for  some  time  in  Montana. 

Electrolytic  Cyanide  Regeneration. — In  the  En- 
gineering and  Mining  Journal  for  May  27,  J.  E. 
Clennell  describes  experiments  undertaken  with  a 
view  of  preventing  the  loss  of  cyanide  by  means  of  re- 
generation with  the  electric  current.  His  results  were 
not  encouraging,  but  his  paper  is  valuable  in  a  nega- 
tive way. 

Agitation  Vats, — In  The  Mining  World  (Chicago) 
for  May  27,  A.  Grothe  controverts  some  previously 
published  criticisms  of  the  Pachuca  vat,  and  explains 
the  efficiency  of  the  work  of  the  vat  in  continuously 
exposing  fresh  surfaces  of  mineral  to  the  action  of  the 
solvent. 

Slime  Treatment  at  Kalgoorlie. — In  the  Mining 
and  Scientific  Press  for  June  3,  M.  W.  Von  Berne- 
witz  describes  the  methods  of  slime  agitation  em- 
ployed at  Kalgoorlie. 

Amalgamation  on  the  Rand. — In  our  May  issue 
we  recorded  that  at  the  April  meeting  at  the  Institution 
of  Mining  and  Metallurgy  a  paper  was  presented  on 
amalgamation  practice  on  the  Randby  W.  R.  Dowling. 
To  prevent  future  misconception  as  to  the  origin  of 
this  paper,  we  ouijht  to  mention  that  it  was  previously 
read  at  the  March  meeting  of  the  Chemical,  Metal- 
lurgical, and  Mining  Society  of  South  Africa. 

Dredging  in  New  South  Wales. — The  Australian 
Mining  Standard  for  May  4  publishes  an  abstract  of 
the  official  reports  on  tlie  production  of  gold  and  tin 
by  dredging  in  New  South  Wales. 

Rankin's  Process  for  Treating  Sulphide  Ores.— 
The  Engineering  and  Mining  Journal  for  June  17 
shortly  describes  H.  D.  Rankin's  process  for  treating 
sulphide  ores  of  all  sorts,  starting  by  sulphatizing  the 
sulphides  by  means  of  nitric  acid.  A  plant  has  been 
erected  at  Lake  City,  Colorado. 

Midvale  Lead-Zinc  Plant.— In  The  Mining  World 
(Chicago)  for  May  6,  13,  and  20  Leroy  A.  Palmer  de- 
scribes the  Midvale  lead-zinc  concentrator,  Utah,  with 
special  reference  to  the  Huff  electrostatic  separator 
for  removing  the  zinc  and  iron. 

Sintering  Experiments.— In  the  Engineering  and 
Mining  Journal  for  June  17.  A.  W.  Hahn  describes 
some  experiments  undertaken  at  the  Reforma  smelter, 
Guerrero,  Mexico,  by  R.  L.  Lloyd,  for  the  purpose  of 
sintering  flue-dust,  speiss,  lead  matte,  etc.,  by  means 
of  a  down  diaught. 

Development  of  the  Blast- Furnace. — The  Engi- 
neering and  Mining  Journal  for  Mav  27  contains 
an  illustrated  paper  by  K.  P.  Mathewson,  tracing  the 
development  of  the  blast-furnace  for  treating  copper 
ores  from  primitive  days  to  modern  times. 

Metallurgy  in  the  Harz  — In  the  Engineering  and 
Mining  Journal  for  June  3,  O.  H.  Hahn  commences 
a  series  of  articles  on  the  metallurgy  of  the  complex 
sulphide  ores  in  the  Marz  mountains,  Germany. 


74 


THE    MINING    MAGAZINE 


Electric  Smelting  of  Iron  Ore. — The  Iron  and 
Coal  Trades  Review  for  June  9  and  16  contains  a 
detailed  account  of  the  results  obtained  at  TroUhattan, 
Sweden,  with  the  electric  furnace  for  smelting  iron 
ore. 

Vanadium  Alloys. — The  Journal  of  the  Franklin 
Institute  for  June  contains  a  lengthy  paper  by  George 
L.  Norris  on  the  production  of  ferro-vanadium,  and 
on  the  manufacture  and  properties  of  vanadium  steel 
and  vanadium  bronze. 

Estimating  Sulphide  in  Cyanide. — Sodium  cyanide 
always  contains  small  quantities  of  sodium  sulphide 
which  is  usually  considered  deleterious  in  gold  extrac- 
tion. E.  C.  Rossiter,  at  the  Birmingham  meeting  of 
the  Society  of  Chemical  Industry,  held  in  March,  dis- 
cussed at  length  the  three  known  ways  of  estimating 
this  sulphide. 

Zinc  Oxide  in  Chemical  Glass-Ware. — In  the  En- 
gineering and  Mining  Journal  for  June  3,  A.  M. 
Smoot  shows  that  zinc  is  sometimes  unexpectedly 
obtained  in  analytical  results  ;  he  finds  that  it  comes 
from  the  refractory  glass  sometimes  used,  that  contains 
zinc  oxide  as  a  part  substitute  for  lime. 

Determination  of  Alumina. — In  the  Engineering 
and  Mining  Journal  for  June  3,  T.  W.  Cavers  de- 
scribes the  method  used  at  the  Tennessee  Copper 
works  for  determining  alumina  in  ore,  slag,  etc. 

Hydrolysis  in  Geological  Chemistry. — In  Economic 
Geology  for  May,  KogerC.  Wells  contributes  a  paper 
explaining  the  principle  of  hydrolysis,  and  showing 
how  the  presence  of  water  under  certain  circumstances 
of  pressure  and  temperature  may  have  an  important 
influence  in  the  reactions  causing  the  deposition  of 
minerals  and  metals. 

Origin  of  Graphite. — In  Economic  Geology  for 
May,  A.  N.  Winchell  describes  the  occurrence  of 
graphite  at  Dillon,  Montana,  and  discusses  the  theories 
of  its  formation. 

Surface  Indications  of  Ore-Shoots.  -In  the  Mining 
and  Scientific  Press  for  May  20,  F.  L.  Ransome 
contributes  to  the  discussion  on  this  subject  previously 
started  by  W.  H.  Storms. 

Quicksilver  Deposits  in  Texas. — In  The  Mining 
World  (Chicago)  for  May  13,  J.  A.  Udden  describes 
the  geology  of  the  quicksilver  deposits  in  the  Zerlingua 
district,  Texas. 

Conditions  in  Honduras.  —  In  the  Mining  and 
Scientific  Press  for  May  27,  Rensselaer  H.  Toll 
contributes  an  article  on  travel  and  mining  in  Hon- 
duras. 

Globe,  Arizona.  —  The  Mining  and  Scientific 
Press  for  June  3  publishes  an  article  by  F.  L.  Ran- 
some on  the  geology  of  the  Globe  copper  district, 
Arizona. 

Water-Power  in  Norway.— At  a  meeting  of  the 
Faraday  Society  held  on  May  2,  A  Scott  Hansen,  of 
Christiania,  read  a  paper  describing  the  application  of 
water-power  in  Norway .  He  estimated  that  the  prices 
charged  for  power  at  the  stations  is  only  from  22  to 
44  shillings  per  horse-poweryear.  The  resources  in 
the  way  of  falls  and  storage  lakes  are  unrivalled  and 
the  indications  are  that  in  the  near  future  many  im- 
portant industrial  developments  will  take  place. 

Tampico  Oilfields. — In  the  Engineering  and  Min- 
ing Journal  for  May  13,  Sydney  H.  Ball  describes 
the  oil  resources  between  Tampico  and  Tuxpam, 
Mexico.  The  subject  was  treated  by  H.  S.  Denny 
in  our  issue  of  July   1910. 

Copies  of  the  original  papers  and  articles  men- 
tioned under  '  Precis  of  Technology  '  and  '  Current 
Literature  '  can  be  supplied  on  application  to  The 
Mining  Magazine. 


BOOKS  REVIEWED 

The    Student's    Lvell.     Edited  by  J.  W.  Judd. 

Second  edition.     Cloth  octavo,  710  pages,  with  736 

illustrations.  London  :  John  Murray.    Price  7s.  6d. 

For  sale  by  The  Mining  Magazine. 

Eheu  fugaces  labuntur  anni !  It  is  SO  years  since 
Lyell  published  his  '  Principles  of  Geology,'  and  75 
have  elapsed  since  his  '  Elements  '  appeared.  In  1871 
he  recast  the  latter  as  the  '  Student's  Elements  ' 
After  his  death,  Professor  Judd,  an  old  and  valued 
friend,  carried  forward  the  study  of  geology  from 
Lyell's  point  of  view,  and  in  1896  published  the  first 
edition  of  the  book  which  is  the  subject  of  this  notice. 
We  have  often  expressed  our  doubts  as  to  the  wisdom 
of  issuing  revisions  of  great  books  whose  authors  are 
dead  and  gone.  We  make  an  exception  in  this  case, 
because  Mr.  Judd  by  old  associations  is  so  well  fitted 
to  keep  the  spirit  of  Sir  Charles  Lyell  still  with  us. 

The  second  edition  of  the  '  Student's  Lyell  '  is  ren- 
dered valuable  by  the  addition  of  an  introductory 
chapter  discussing  the  influences  and  preparations  in- 
cidental to  the  birth  of  the  line  of  thought  which  is 
outlined  in  Lyell's  '  Principles.'  It  revives  memories 
of  the  early  study  of  geology  in  its  application  to  the 
gradual  developments  of  the  inorganic  and  organic 
kingdoms,  otherwise  the  history  of  the  world.  The 
controversies  of  Hutton  and  Werner,  and  the  gradual 
transition  of  Lyell's  studies  from  entomology  to  botany 
and  zoology  and  then  to  geology,  are  authoritatively 
recorded.  Lyell's  '  Principles  '  established  order  out 
of  chaos  and  prepared  the  way  for  the  theory  of  Evolu- 
tion, all  the  great  pioneers  of  which,  Darwin,  Wallace, 
Hooker,  Huxley,  and  Haeckel,  always  warmly  acknow- 
ledged their  indebtedness.  Lyell's  sphere  was  paleon- 
tology, not  ore  deposits  ;  but  none  the  less  his  books 
demand  a  place  in  the  library  of  the  economic  geolo- 
gist. 
Journal  of  the  Institute  of  Metals,  Vol.  V. 

Paper  covers,   420  pages.      Illustrated.     London  : 

The  Institute  of  Metals.     Price  21s. 

This  volume  contains  a  report  of  the  half-yearly 
meeting  held  in  January.  The  most  important  paper 
is  that  on  Corrosion  of  Metals  by  G.  D.  Bengough. 
Over  one-third  of  the  volume  is  occupied  with  ab- 
stracts of  papers  published  by  the  world's  technical 
Press,  during  a  period  of  six  months,  on  the  occur- 
rence and  treatment  of  the  non-ferrous  metals.  We 
are  grieved  to  find  that  The  Mining  Magazine  and 
the  Mining  and  Scientific  Press  have  not  published 
anything  worthy  of  record  during  that  time. 

Operation  of  the  Goldfield  Consolidated 
Mill.  By  J.  W.  Hutchinson.  Pamphlet,  20 
pages.  Illustrated.  San  Francisco  :  Mining  and 
Scientific  Press  ;  London  :  Tlie  Mining  Maga- 
zine.    Price  2s. 

This  is  a  reprint  of  a  series  of  articles  that  appeared 
in  the  Mining  and  Scientific  Press  during  May  and 
June.  It  gives  full  practical  details  of  the  work  done 
at  one  of  the  most  modern  all-sliming  plants,  and 
will  be  of  great  help  to  the  cyanide  metallurgist.  We 
give  an  outline  of  the  scope  of  the  paper  in  Precis  of 
Technology  this  month. 

The  Davis  Handbook  of  the  Porci:pine  (tOLD 

District.     By   H.   P.   Davis.     Paper  covers,   130 

pages,    with    many    maps  and    illustrations.     New 

York  :   H.  P.  Davis,  25  Broad  Street.     Price  4s.  6d. 

This  pamphlet  contains  a  complete  account  of  the 

Porcupine  goldfield,  its  discovery  and  development  ; 

also  of  all  the  companies  and  individuals  operating 

there. 


I 


JULY,    1911 


75 


COMPANY   REPORTS 

Taquah  Mining  &  Exploration. — This  company  is 
now  one  of  the  Oceana  Consolidated  group  of  West 
African  gold  mines.  It  operates  the  Taquah  mine 
and  owns  a  large  share  in  the  Abosso  farther  north  on 
the  same  line  of  banket  deposit.  For  some  years  both 
of  these  mines  were  under  the  management  of  G.  A. 
Stnckfeld.  A  few  months  ago  Mr.  Stockfeld's  services 
were  transferred  to  the  West  African  Trust,  a  develop- 
ment company  belonging  to  the  same  group,  and  J .  W. 
Nevvbery  succeeded  him.  R.Recknagel  andS. R.Adams 
then  examined  the  mines,  re-estimated  the  ore  reserves, 
and  made  suggestions  for  the  modification  of  mining  me- 
thods and  the  improvement  of  the  power-plant.  More 
recently  W.  R.  Feldtmann  has  been  appointed  con- 
sulting engineer.  In  June  1910  a  serious  accident 
occurred  in  the  main  shaft  and  mining  operations  had 
to  be  suspended.  It  was  decided  not  to  resume  mining 
and  milling,  but  to  push  ahead  with  development 
work.  Owing  to  these  alterations  and  reorganizations 
it  has  not  been  possible  to  issue  the  report  for  the  year 
ended  June  30,  1910,  until  now.  It  shows  that  during 
the  year  65,222  tons  of  ore  yielded  39,220  oz.  gold, 
worth  /166,553,  or  51s.  per  ton.  The  working  ex- 
penses in  West  Africa  and  London  were  ;^109,546  ; 
^28,534  has  been  written  off  for  development  redemp- 
tion, /30,422  allowed  for  depreciation,  /9416  and 
/3529  written  off  the  shaft-sinking  account  and  explor- 
ation account  respectively.  On  February  28,  Mr. 
Recknagel  estimated  the  ore  reserve  at  102,370  tons, 
averaging  78s.  3d.  per  ton  ;  he  rejected  107,370  tons 
which  he  considered  unprofitable. 

Abosso. — In  continuation  of  the  preceding  para- 
graph we  give  some  information  contained  in  the 
Abosso  report  for  the  year  ended  June  30,  1910.  Dur- 
ing that  period  77,623  tons  of  ore  was  sent  to  the  mill, 
and  by  amalgamation  and  cyaniding  41,125  oz.  gold 
was  recovered,  worth  /174,834,  or  45s.  per  ton.  The 
working  profit  was  /51,196,  out  of  which  /14,310  has 
been  written  off  for  depreciation  and  for  shaft  exten- 
sions, and  /5894  has  been  paid  in  taxes,  !ea\ing  a  net 
profit  of  /30,991.  The  year  commenced  with  a  bal- 
ance of  /31,203,  and  dividends  amounting  to  ;^60,000 
have  been  distributed  during  the  year,  being  at  the 
rate  of  15%,  leaving  a  balance  carried  forward  of 
;^2194.  An  additional  50  stamps  are  now  being  erec- 
ted, as  also  is  an  electrical  pumping-plant  at  the  main 
shaft.  When  the  latter  is  at  work  sinking  will  be 
re-commenced.  On  February  28,  Mr.  Recknagel  esti- 
mated the  ore  reserve  at  284,028  tons,  averaging  47s. 
3d.  per  ton,  and  58,210  tons,  averaging  19s.  9d.  per 
ton. 

Prestea  Block  A. — Two  years  ago  additional  work- 
ing capital  was  supplied  for  this  West  African  gold 
mine  by  Wernher,  Beit  &  Co.,  the  Consolidated  Gold 
Fields,  Fanti  Consols,  and  the  United  Exploration  Co. 
Milling  was  suspended,  development  work  was  actively 
conducted,  and  additional  plant  provided.  The  re- 
port now  issued  covers  the  year  1910,  and  shows  that 
on  December  31  the  ore  reserve  was  678,859  tons 
averaging  43s.  lOd.  per  ton.  The  main  shaft  is  down 
624  ft.  and  the  Appantoo  724  ft.  The  report  is  accom- 
panied by  a  vertical  section  of  the  mine  showing  the 
blocks  of  ore  and  their  average  assay-value.  The  direc- 
tors record  with  satisfaction  the  completion  of  the 
railway  to  Prestea  at  the  beginning  of  1911.  Of  the 
new  110  stamps,  60  have  been  erected,  and  40  started 
crushing  at  the  beginning  of  May  this  year.  During 
1910  an  additional  150,000  shares  were  issued  at  a 
premium  of  /53,750,  which  amount  has  been  set 
against  depreciation  of  plant  and  buildings.   In  January 


a  resolution  was  passed  increasing  the  capital  from 
/850,000  to  /1, 150, 000,  but  the  new  shares  have  not 
yet  been  issued.  Out  of  the  new  shares,  199,877  are 
to  be  paid  to  the  Prestea  Mines  for  the  purpose  of 
acquiring  the  property  of  that  company  adjoining  that 
of  Block  A. 

Talisman  Consolidated. — This  company  was  formed 
in  1899  to  acquire  a  gold  mine  near  the  Ohinemuri 
river  in  the  province  of  Auckland,  New  Zealand,  and 
in  1904  it  was  reconstructed  in  order  to  purchase  the 
neighbouring  Woodstock  property.  Dividends  were 
first  paid  in  1906  and  since  then  the  profits  iiave  been 
large  and  increasing.  About  a  year  ago  important 
discoveries  of  rich  ore  were  made  on  the  lowest  level. 
Bewick,  Moreing  &  Co.  are  the  managers,  and  H. 
Stansfield  is  the  superintendent.  The  report  for  the 
year  ended  February  28  shows  that  45,850  tons  of  ore 
was  milled,  yielding  43,687  oz.  gold  and  186,240  oz. 
silver,  which  realized  ;^207,874,  or  about  /4.  12s.  per 
ton.  The  cost  in  New  Zealand  and  London  was 
/85,337,   taxes  absorbed  /9468,  and  IZlbl   was  al- 


Talisman  Mill. 

lowed  for  depreciation.  The  di\idend  distributed  was 
;/^100,447.  During  the  last  two  years  much  money 
has  been  spent  in  new  plant,  particularly  pumps  and 
tube-mills.  Some  of  the  funds  have  been  supplied 
out  of  profits,  but  it  was  decided  last  summer  to  pro- 
vide the  remainder  by  the  issue  of  45,000  new  shares 
at  25s.  each.  These  were  readily  absorbed  and  the 
capital  now  stands  at  /345,000.  Since  1906  the  total 
distribution  of  dividends  has  amounted  to  /534,J28. 
Mr.  Stansfield  reports  that  during  the  year  the  ore 
developed  has  been  about  equal  to  that  sent  to  the 
mill,  and  assays  £6  per  ton. 

Great  Fingall. — In  our  issue  of  June  last  year,  we 
recorded  that  this  gold  mine  situated  at  Day  Dawn, 
West  Australia,  after  having  been  an  important  pro- 
ducer from  1900  to  1908,  came  to  the  end  of  its  main 
resources  and  since  then  operations  have  been  restric- 
ted. The  report  for  1910  show-s  that  development 
work  is  still  being  actively  conducted  and  some  profit- 
able ore  has  been  disclosed  in  the  lower  levels.  Only 
40  of  the  100  stamps  are  now  at  work  and  during 
the  year  they  milled  125,871  tons,  which  by  amalga- 
mation and  cyaniding  yielded  35,978  oz.  In  addition 
the  new  filter-press  plant  treated  128.149  tons  of  accu- 
mulated slime,  and  extracted  8822  oz.  The  income 
from  the  sale  of  gold  was  /191,100  and  tiie  working 
profit  was  ^33,417.    Out  of  this /6459  was  allowed  for 


76 


THE    MINING    MAGAZINE 


depreciation  and  /5316  was  paid  as  taxes.  The  divi- 
dend absorbed  /25,000,  being  at  the  rate  of  20%.  No 
estimate  is  given  of  the  broken  ore,  of  the  ore  in  pillars, 
and  of  ore  in  the  lowest  levels,  but  it  is  stated  that  the 
last-named  source  promises  to  be  an  important  one. 
A  year  ago  shares  were  bought  in  the  Taquah  Central 
Mines,  West  Africa.  So  far  the  development  work 
done  on  the  property  has  revealed  no  profitable  ore. 
Bewick,  Moreing  &  Co.  are  the  general  managers. 

Great  Boulder  Proprietary. — 
Though  other  mines  at  Kalgoorlie 
have  their  troubles,  the  Great  Boul- 
der Proprietary  has  so  far  escaped 
these  worries.  For  fifteen  years  its 
success  has  been  uninterrupted,  and 
the  report  for  1910  shows  as  yet  no 
cloud  on  the  horizon.  During  the 
year,  195,407  long  tons  of  sulpho-tel- 
luride  ore  was  raised  and  treated, 
yielding  gold  worth  /220,961  by 
amalgamation,  and  /366,947  by  cya- 
niding,  making  a  total  output  worth 
;^587,908.  The  profit  was  /326,560, 
out  of  which/29,950  has  been  paid  as 
taxes,  /30,000  placed  to  deprecia- 
tion, and  ^262,500  distributed  as 
dividend.  The  working  cost  per  long 
ton  was  26s.  2d.  or  23s.  3d.  per  short 
ton.  These  results  are  much  the 
same  as  in  1909.  During  1910,  5541 
ft.  of  development  work  was  done  and 
the  reserve  was  increased  by  9100 
tons,  standing  on  December  31  at 
760,177  long  tons,  averaging  15dwt. 
Sinking  has  been  continued  at  the 
Main  and  Edwards  shafts,  the  for- 
mer being  now  2844  ft.  deep  and  the 
latter  2842  ft.  The  two  have  been 
connected  at  2500  ft.  Richard  Ham- 
ilton, the  manager,  reports  that  indi- 
cations at  depth  are  good,  and  that 
the  exploration  of  the  northerly  ex- 
tensions of  the  main  orebody  are  giv- 
ing promising  results.  Boring  opera- 
tions have  at  the  2800  ft.  level  proved 
the  existence  of  two  parallel  veins  of 
excellent  value. 

St.  John  Del  Rey. — This  company 
owns  the  Morro  Velho  gold  mine  in 
Minas  Geraes,  Brazil,  and  has  just 
completed  the  80th  year  of  its  exis- 
tence. The  mine  is  notable  because 
it  is  the  deepest  in  the  world.  Since 
giving  an  account  of  the  last  half-yearly  report  in  our 
issue  of  December  last  another  level  has  been  opened 
up  at  a  vertical  depth  of  4600  ft.  below  adit  or  4296  ft. 
below  the  surface  ;  already  474  ft.  of  driving  has  been 
done  on  this  level  and  some  ore  has  been  stoped.  The 
report  for  the  year  ended  February  28  shows  that  min- 
ing, milling,  and  development  work  has  given  satisfac- 
tory results  and  the  only  adverse  circumstance  was  the 
insufficient  supply  of  water  power  owing  to  drought, 
and  the  consequent  extra  expense  on  steam  power. 
The  amount  of  ore  raised  was  193,195  tons,  of  which 
189,600  tons  was  sent  to  the  130-stamp  mill.  The 
yield  by  amalgamation  and  cyanide  was  98,726  oz. 
realizing  ;^421,178  or  44s.  4d.per  ton.  The  working 
cost  was  ;^265,058  or  28s.  per  ton,  development 
/12,387  or  Is.  4d.  per  ton,  and  London  expenses 
/3692.  In  addition  2^43,057  was  allocated  to  capital 
expenditure  ;  /5425  was  paid  as  interest  on  debentures, 
/lO.OOO  as  dividend  on  preference  shares,  being  at  the 


rate  of  10%,  and  ^^50,078  was  distributed  on  the  or- 
dinary shares,  being  at  the  rate  of  Is.  lOd.  per  share, 
an  increase  of  2d.  per  share  as  compared  with  the  pre- 
vious year.  The  reserve  fund  invested  in  high-class 
securities  has  been  re-valued  and  now  stands  on  the 
books  at  ;^96,472  ;  it  is  used  in  part  to  improve  the 
financing  of  drafts  between  England  and  Brazil.  As 
usual  the  manager,  George  Chalmers,  gives  a  full 
account  of  progress.     A  new  unit  of  water  power  from 


SoratB  Mt 

2/000  f 


lllimani  M^ 

21000  f 
COCf/ABA    BA 

o 


Scale    or    Miles 
Railways  in  openhon 
^g  Railways  planned. 


Parts  of  Chile  and  Bolivia  sliowing  position  of  Poderosa  Mine  nt  Collahuasi. 


the  Peixe  river  will  shortly  be  at  work  and  will  pro- 
vide an  additional  1000  hp.  He  also  reports  that  the 
additional  ventilating  plant  is  nearly  ready.  By  its 
means  it  is  expected  that  the  temperature  of  the  work- 
ing faces  will  be  reduced  sufficiently  to  make  it  pos- 
sible to  mine  down  to  6500  ft.  The  question  of  venti- 
lation has  received  close  attention  and  the  experiments 
made  to  ascertain  the  temperature  of  the  rocks  are  of 
considerable  interest.  Reference  to  this  subject  is 
made  in  our  Precis  of  Technology.  The  ore  reserve 
is  estimated  at  1,158,560  tons,  or  sufficient  for  five 
years'  work.  Owing  to  the  nature  of  the  methods  of 
mining,  no  further  development  will  be  possible  for 
two  years,  until  the  17th  and  18th  levels  are  fully 
opened.  We  refer  our  readers  to  the  excellent  vertical 
section  of  the  workings  which  appeared  in  our  issue 
last  month. 

Poderosa. — In  our  issue  of  November  last  we  gave 
an  abstract  of  the  first  annual  report  of  this  copper 


JULY,    1911 


77 


mining  company  covering  the  year  1909,  and  recorded 
the  history  to  date.  In  the  October  number  immedi- 
ately preceding  we  pubhshed  an  article  describing  the 
mines  written  by  the  first  manager  Robert  Havvxhurst. 
The  mines  are  in  the  Andes  at  Collahuasi,  Chile,  not 
far  from  the  Bolivian  border  and  are  situated  15,000  ft. 
above  the  sea.  The  position  is  shown  in  the  accom- 
panying map  and  we  also  give  an  illustration  of  native 
huts.  The  ore  deposits  are  rich  in  copper.  The  direc- 
tors made  the  initial  mistake  of  declaring  large  divi- 
dends without  reckoning  on  the  necessity  of  providing 
funds  for  further  development,  and  consequently  the 
company  soon  arrived  at  a  critical  position .  The  direc- 
tors chcse  to  throw  the  blame  on  Mr.  Hawxhurst,  but 
most  of  them  have  thought  fit  to  resign  and  make  way 
for  others.  C.  H.  Macnutt  was  appointed  manager  in 
the  meantime  and  he  took  control   in  the  middle  of 


has  been  counteracted,  he  intends  to  conduct  develop- 
ment work  on  a  large  scale  in  the  near  future.  During 
1910  the  income  from  the  sale  of  ore  was  /191,870,  and 
the  net  profit  was  ;f38,471.  The  year  began  with  a 
debit  balance  of  £bl ,211  which  is  now  reduced  to 
;^28,801.  Since  the  close  of  the  year  the  directors 
have  been  able  to  redeem  ;^36,000  of  debentures.  Ex- 
periments have  been  actively  conducted  in  connection 
with  the  concentration  of  second  grade  and  dump  ores 
and  a  plant  is  to  be  erected. 

Rezende. — In  our  issue  of  July  last  year  we  recorded 
the  earlier  history  of  this  gold  mine  at  Umtali,  near 
the  eastern  boundary  of  southern  Rhodesia,  and  how 
after  continued  failure  for  18  years  the  company  had 
been  placed  on  a  more  secure  footing  by  the  Anglo- 
French-Farrar  group.  Theexpectationsthenexpressed 
have  been  substantiated,  and  the  report  for  1910  shows 


NATIVE  MINERS'   HUTS   IN    THE  ANDES. 


1909.  The  report  for  1910  now  issued  shows  that  the 
first  half  of  the  year  was  occupied  in  reorganization  of 
operations  at  the  mine  and  the  output  was  curtailed. 
By  the  middle  of  the  year  it  was  possible 'to  increase 
the  output.  The  total  amount  of  ore  raised  during  the 
year  from  the  three  different  workings,  Poderosa,  San 
Carlos,  and  Rosario,  was  28,530  tons  averaging  178% 
copper,  21,442  tons  averaging  4%  ,  and  5102  tons  aver- 
aging 2i% .  The  deliveries  of  first  class  ore  were  21 ,797 
tons  averaging  22%  copper  and  7'8  oz.  silver,  shipped 
from  Mejillones,  and  1544  tons  averaging  13%  copper 
and  4'2  oz.  silver  shipped  from  Antofagasta.  Some  of 
this  ore  delivered  came  from  the  dumps,  to  the  extent 
of  3400  tons  some  of  which  averaged  25%,  copper. 
Development  during  the  year  exposed  17,180  tons 
averaging  23%  copper,  and  on  December  31  the  ore 
reserve  was  estimated  at  35,000  tons  averaging  22% 
copper  and  7  oz.  silver.  The  dumps  are  reported  to 
contain  96,000  tons  averaging  4'7%  copper.  In  Sep- 
tember Mr.  Macnutt  started  to  concentrate  the  dump- 
ore  by  means  of  hand-jigs  and  sluice-boxes  and  their 
work  has  already  proved  profitable.  Owing  to  short- 
ness of  funds  Mr.  Macnutt  has  not  been  able  to  do  as 
much  prospecting  work  as  is  desirable,  but  now  that 
the  evil  effects  of  premature  distribution  of  dividends 


a  profit  of  /9015  which  has  been  carried  forward. 
C.  R.  Finder  is  the  consulting  engineer,  and  S.  R. 
Jameson  is  manager.  The  report  of  the  latter  shows 
that  during  the  year  under  review  30  stamps  crushed 
43,800  tons  of  ore  averaging  7'6dwt.,  and  extracted 
8774  oz.  gold  by  amalgamation.  The  cyanide  plant 
extracted  4541  oz.,  and  1534 oz.  was  contained  in  con- 
centrate that  was  shipped  abroad.  The  total  yield 
was  14,849  cz.,  or  6'7S  dwt.  per  ton.  The  revenue 
was  /64,599,  and  the  working  cost  /46.975,  leaving  a 
profit  of  /16,624.  Part  of  the  property  is  leased  to 
tributors  and  an  income  of  i.'44S  was  received  during 
the  year  from  this  source  ;  as  the  tributors'  plant  has 
been  greatly  improved  recently  and  tiie  ore  treated  is 
now  higher  in  value,  an  increased  revenue  will  accrue 
during  the  current  and  succeeding  years.  From  the 
profit  quoted  above  liad  to  be  deducted  London  ex- 
penses, debenture  interest,  and  depreciation.  Mr. 
Jameson  reports  the  ore  reserve  on  December  31  at 
112,980  tons  averaging  758  dwt.  together  with  17,033 
tons  of  partly  developed  ore.  In  addition,  in  the 
workings  let  on  tribute  60,427  tons  is  estimated  as 
developed  ;  this  ore  was  included  in  the  general  esti- 
mate last  year.  A  year  ago  the  issued  capital  was 
;^48,990  out  of  an  authorized  £.'120,000.     Since  then 


78 


THE     MINING     MAGAZINE 


18,012  shares  have  been  allotted  at  par  to  guarantors 
of  the  debenture  issue,  and  33,501  have  been  sold  at 
£2.  2s.  6d.  With  the  money  thus  raised  ;^46,860  of 
debentures  have  been  extinguished,  leaving  only  /640 
outstanding.  Many  improvements  have  recently  been 
made  in  the  gold-extraction  processes.  The  most  im- 
portant is  the  treatment  of  the  rich  concentrate  on  the 
spot  by  sliming  with  mercury  in  a  wheeler  pan  and 
then  cyaniding  the  tailing.  In  this  way  a  95%  extrac- 
tion can  be  obtained  at  a  cost  of  49s.  6d.  per  ton  in- 
cluding 18s.  7d.  left  in  the  residue,  as  compared  with 
£b.  10s.  the  cost  when  shipping  the  ore. 

Geldenhuis  Deep. — In  1909  the  properties  of  the 
Geldenhuis  Estate,  Geldenhuis  Deep,  and  Jumpers 
Deep  were  amalgamated,  and  the  organization  con- 
tinued under  the  name  of  the  Geldenhuis  Deep.  The 
Geldenhuis  Estate  started  work  on  the  outcrop  in 
1887,  and  was  practically  exhausted  at  the  time  of 
amalgamation,  nothing  but  pillars  being  left.  The 
Geldenhuis  Deep  commenced  operations  in  1895  and 
the  Jumpers  Deep  in  1898.  The  mill  of  the  combined 
companies  consists  of  420  stamps  and  6  tube-mills. 
The  company  is  one  of  the  Rand  Mines  group,  G.  E. 
Webber  has  been  consulting  engineer,  but  is  now  re- 
tiring, and  H.  Musson  Thomas  is  manager.  The  re- 
port for  1910  shows  that  owing  to  the  scarcity  of  labour 
it  has  not  been  possible  to  reach  the  maximum  output 
that  was  expected  at  the  time  of  amalgamation,  the 
amount  treated  being  9000  tons  per  month  short.  In 
fact  the  output  of  ore  was  rather  less  than  in  1909, 
but  on  the  other  hand  the  profit  was  greater  This  is 
due  to  the  keen  application  of  the  principle  of  not 
mining  and  milling  waste,  which  has  on  many  occa- 
sions been  the  subject  of  papers  and  discussions  by 
Mr.  Thomas.  During  the  year,  1,058,175  tons  was 
raised,  and  after  the  removal  of  21%  waste  827,065 
tons  was  sent  to  the  mill,  averaging  7d\vt.  The  yield  of 
gold  by  amalgamation  and  cyanide  was  276,002  oz.,  or 
668  dwt.  per  ton  milled.  The  revenue  was  /1, 156,543, 
or  28s.  per  ton  milled.  The  cost  was  /905,238,  or 
21s.  lid.  per  ton  milled,  leaving  a  profit  of  /251,305, 
or  6s.  Id.  per  ton.  During  the  year,  25,829  ft.  of 
development  work  was  done  and  the  ore  disclosed 
thereby  was  1,153,777  tons  averaging  52  dwt.  On 
December  31  the  ore  reserve  was  2,521,481  tons  aver- 
aging 61  dwt.  It  will  be  seen  that  the  ore  recently 
developed  is  of  lower  grade  than  the  average  reserve  ; 
in  the  western  part  of  the  property  the  grade  is  dis- 
couragingly  poor  in  the  lower  levels.  There  is  a 
large  amount  of  ore  left  in  the  pillars  still  to  be  ex- 
tracted, but  owing  to  some  of  the  ground  being  caved 
it  is  not  easy  to  estimate  its  quantity  and  quality. 
Sand-filling  is  being  adopted  so  that  these  pillars  may 
be  recovered.  Much  money  has  been  spent  during 
the  year  on  impro\ing  the  power  plant  and  in  providing 
double-stage  winding  in  shafts  No.  2  and  No.  3. 

Durban  Roodepoort  Deep. — This  is  one  of  the 
Rand  Mines  group,  and  the  mine  is  situated  in  the 
western  Rand.  Milling  started  in  1898,  but  it  was 
not  until  1908  that  any  dividend  was  paid .  The  report 
for  the  year  1910  shows  that  a  smaller  profit  was  made 
than  in  1908  and  1909,  owing  to  higher  costs.  The 
cost  of  working  at  this  mine  has  always  been  high 
compared  with  the  average  on  the  Rand.  In  1909 
it  had  been  reduced  to  22s.  9d.  per  ton  milled,  but  for 
1910  it  has  increased  again  to  24s.  6d.  The  cause  for 
this  advance  was  partly  the  inefficiency  of  labour  and 
partly  the  greater  amount  of  development  and  shaft- 
sinking  done.  During  the  year  309,067  tons  was 
raised  and,  after  the  removal  of  22%  waste,  240,530 
tons  went  to  the  mill,  which  consists  of  100  stamps 
and  3  tube-mills.     The  content  of  the  ore  milled  was 


estimated  at  7  57  dwt.  The  yield  of  gold  by  amalga- 
mation was  61,894  oz.  and  by  cyanide  23,416  oz., 
making  85,310  oz.  in  all,  or  7  dwt.  per  ton  milled. 
The  revenue  was  ;^357,128,  or  29s.  8d.  per  ton,  and 
the  cost  was  /295,407,  or  24s.  7d.  per  ton,  leaving  a 
profit  of  ;^61,721,  or  5s.  Id.  per  ton.  Out  of  this, 
^24,285  has  been  allocated  to  capital  expenditure  on 
new  plant,  and  /3550  was  paid  as  taxes  ;  the  dividend 
was  /33.000,  being  at  the  rate  of  7^%.  During  the 
year,  development  has  been  hindered  by  lack  of 
labour,  and  consequently  the  number  of  feet  driven 
was  smaller  than  was  expected,  but  on  the  other  hand 
the  ore  disclosed  has  been  of  better  value.  It  is 
worthy  of  note  that  in  the  case  of  this  mine  the 
content  is  increasing  with  depth.  On  December  31 
last  the  reserve  was  estimated  at  867,551  tons,  aver- 
aging 67  dwt.,  and  in  addition  the  ore  left  in  pillars 
was  194,426  tons  averaging  7  3  dwt.  The  average 
content  of  the  ore  mined  during  1910  was  less  than  it 
should  have  been,  owing  to  the  bad  results  obtained 
by  machine-drills.  These  have  since  been  replaced 
once  more  by  hand-drilling.  A  system  of  ventilating 
is  being  installed  in  order  not  only  to  improve  the 
quality  of  the  mine  air  but  to  reduce  the  heat  of  the 
workings. 

Rose  Deep. — This  is  another  of  the  Rand  Mines 
group,  and  is  isolated  from  the  others,  being  situated 
to  the  east  beyond  the  Consolidated  Gold  Fields  group. 
It  is  on  the  dip  of  the  Primrose,  May,  and  Glencairn. 
The  company  was  formed  in  1894  and  milling  started 
in  1897.  At  the  end  of  1909  the  adjoining  Cilen  Deep 
was  absorbed  and  the  two  mines  are  now  worked 
under  one  organization.  The  combined  metallurgical 
plant  contains  300  stamps  and  7  tube-mills.  During 
the  year  1910  mining  has  been  greatly  hindered  in  the 
old  Rose  Deep  part  by  caving  and  by  the  weakening 
of  the  winding  shaft.  Not  only  was  the  output  re- 
stricted, but  much  expense  was  entailed  in  making 
good  the  damage.  Consequently  the  yield  was  less 
than  normal  and  the  cost  higher  ;  the  profit  was 
£40,000  less  than  the  combined  profits  of  the  two 
mines  in  1909.  The  amount  of  ore  raised  was  761 ,751 
tons  and,  after  the  removal  of  138%  waste.  656.954 
tons  was  sent  to  the  mills,  the  normal  annual  capacity 
of  which  is  765,000  tons.  The  estimated  content  of 
the  mill-ore  was6'9  dwt.  By  amalgamation  147,453oz. 
was  recovered,  and  by  cyanide  75,454  oz.,  making  a 
total  of  222,907 oz.,  or  6"8  dwt.  per  ton  milled.  The 
revenue  was  /934,154,  or  28s.  5d.  per  ton,  and  the 
cost  ;^618,878.  or  18s.  lOd.  per  ton,  leaving  a  profit  of 
/315,276,  or  9s.  7d.  per  ton.  The  development  work 
done  during  the  year  was  16,230  ft.,  and  993,512  tons 
averaging  6  3  dwt.  was  added  to  the  ore  reserve,  which 
on  December  31-  stood  at  3,553,474  tons,  averaging 
61  dwt.  The  dividend  absorbed  /280,000.  being  at 
the  rate  of  40%  ;   /25,463  was  paid  as  tax. 

Brakpan. — This  is  a  second  deep  level  in  the  far 
east  Hand  and  is  below  the  Kleinfontein  and  Van  Ryn 
Deep.  It  is  controlled  by  the  Consolidated  Mines 
Selection  Company  ;  W.  L.  Honnold  is  consulting 
engineerandC  B.  Brodigan  is  manager.  Preparations 
for  work  have  been  carefully  and  thoughtfully  planned 
and  the  development  was  conducted  on  a  large  scale 
before  any  treatment  plant  was  provided  Two  vertical 
shafts  have  been  sunk  one  below  the  other  on  the  dip  : 
they  cut  the  gold-bearing  strata  at  3100  and  3700ft. 
respectively,  and  are  connected  by  an  incline.  De- 
velopment has  been  done  on  fourteen  levels,  and  to 
the  end  of  1910  the  footage  was  37,744,  the  ore  reserve 
then  being  1,720,181  tons  averaging  6  56  dwt.  over  52 
inches.  In  recording  progress  at  this  mine  in  our  issue 
of  July  last  year,  we  mentioned  that  the  mill  was  to 


JULY,    1911 


79 


contain  160  stamps  weighing  2000  1b.  each,  and  that 
the  capacity  was  to  be  60,000  tons  per  month,  but  that 
many  of  the  details  were  not  then  settled  Part  of  the 
plant  is  now  complete  and  should  be  in  operation  by 
the  time  this  paragraph  is  published.  Air-agitation, 
Butters  filters,  and  the  Merrill  method  of  zinc-dust 
precipitation  have  been  adopted.  Probably  the  capa- 
city of  the  plant  will  be  greater  than  was  originally 
estimated. 

Village  Main  Reef. — The  report  of  this  mine,  in  the 
central  part  of  the  Rand,  for  the  year  1910  is  of  par- 
ticular interest,  as  it  gives  the  results  obtained  by  the 
adoption  of  H.  F.  Marriott's  policy  of  eliminating 
ore  of  doubtful  profitableness.  The  company  is 
housed  by  the  Consolidated  Gold  Fields,  but  the  con- 
trol and  technical  direction  is  with  the  Wernher-Beit- 
Eckstein  group.  The  property  is  on  the  dip  of  the 
Wemmer,  Salisbury,  Jubilee,  and  part  of  the  City  & 
Suburban  ;  in  1906  the  first-named  was  acquired  and 
absorbed.  Milling  started  in  1892  with  10  stamps  and 
the  plant  has  been  gradually  increased  until  it  now 
contains  220  stamps  and  6  tube-mills. 
During  the  last  three  years  the  profits 
have  greatly  increased.  Judging  by 
the  reef  area  the  mine  may  be  ex- 
pected to  be  productive  for  four  years 
more.  The  report  for  1910  shows 
that  588,552  tons  was  raised  from  the 
mine  and,  after  the  rejection  of  16% 
waste,  492,446  tons  was  sent  to  the 
mill,  averaging  8'84  dwt.  The  yield 
by  amalgamation  was  133,846  oz., 
and  by  cyanide  71,247  oz.,  a  total  of 
205,093  oz.,  or  83  dwt.  per  ton.  A 
year  ago  practically  the  same  amount 
of  ore  was  raised,  but  only  12%  of 
waste  was  removed  at  the  surface, 
and  the  average  content  of  the  ore 
milled  was  7^  dwt.  The  policy  during 
1910  was  to  maintain  the  output  of 
the  mine,  but  to  leave  behind  more 
of  the  low  grade  ore.  The  income 
was  /860,839,  or  34s.  lOd.  per  ton  of 
ore  milled,  and  the  expenditure  was 
/410,433,  or  16s.  7d.  per  ton,  leaving 
a  profit  of  /450,406,  or  18s.  3d.  per 
ton.  During  1909  the  revenue  was  /787,161 
30s,  7d.  per  ton,  the  cost  ;f394,341,  or  15s.  4d. 
ton,  and  the  profit  ;^392,820~  or  15s.  3d.  per  ton. 
will  be  seen  that  though  expenses  were  higher,  owing 
to  the  greater  cost  of  mining  and  the  smaller  tonnage 
milled,  the  gross  profit  and  the  profit  per  ton  were 
substantially  increased.  The  ore  reserve  on  Decem- 
ber 31  was  1,775,175  tons,  averaging  9  2  dwt.,  as  com- 
pared with  1,999,784  tons  averaging  8'9  dwt.  the  year 
before.  The  1909  report  included  much  unprofitable 
rock  in  the  reserve.  This  has  now  dropped  out,  and 
the  amount  of  ore  to  be  ultimately  raised  and  milled 
has  been  reduced.  The  consulting  engineer,  H.  Stuart 
Martin,  warns  shareholders  that  the  life  of  the  mine 
will  be  shortened  by  this  policy,  and  that  the  monthly 
yield  will  be  subject  to  marked  fluctuations.  The  pro- 
fit mentioned,  /450,406,  was  subject  to  many  deduc- 
tions, including  /'SI, 652  expenditure  on  electric  and 
sand-filling  plant,  and  taxes  /58.10O.  The  dividend 
was  /330,400,  being  at  the  rate  of  70%,  the  same  as 
last  year,  but  an  additional  /40,000  was  carried  for- 
ward . 

Mountain  Copper.— The  report  of  this  company 
for  1910  discloses  an  unpromising  state  of  affairs.  It 
will  be  remembered  that  the  company  was  formed  in 
1896  by  the  Rio  Tinto  people  to  acquire  the  Mountain 


copper  mine  situated  at  Iron  Mountain,  Shasta  county. 
California,  together  with  a  smelter  at  Keswick.  For 
some  years  large  profits  were  made  and  in  1901  the 
output  was  13,270  tons  of  copper.  Subsequently  the 
orebody  was  found  to  be  of  less  extent  than  was 
originally  supposed,  so  in  1902  the  company  was  recon- 
structed by  changing  the  shares  into  redeemable  deben- 
tures. Owing  to  persistent  smelter-fume  litigation, 
only  a  small  portion  of  these  debentures  have  been 
redeemed,  and  the  profits  applied  to  the  acquisition  of 
sulphuric  acid  plant  and  fertilizer  works.  In  reviewing 
the  progress  of  the  company  a  year  ago  we  recorded 
that  the  profit  had  dropped  to  /24,557,  which  was 
not  sufficient  to  pay  the  6%  interest  on  the  /750,000 
of  outstanding  debentures.  The  report  for  1910  gives 
little  specific  information  except  that  the  result  of  the 
year's  work  was  a  deficit  of  /3041.  The  loss  is  attri- 
buted to  the  fall  in  the  price  of  copper,  the  necessity 
for  writing  down  the  value  of  the  stock  in  hand,  the 
high  cost  of  production,  and  the  unfavourable  course 
of  business  in  California  generally.     The  board  has 


or 

per 

It 


Copper  Dintrict  of  ShfiKta  Cuuntij,  Californin. 

made  special  enquiry  into  the  conditions  on  the  spot, 
and  has  in  consequence  decided  to  close  one  of  the 
acid  works.  C.  VV.  Fielding,  who  originally  intro- 
duced the  property  here,  has  left  the  board,  and 
Lewis  T.  Wright  has  resigned  as  manager. 

EnglishCrownSpelter.— This  company  was  founded 
in  1883  to  acquire  the  distilling  works  of  the  Crown 
Zinc  Co.  in  Swansea,  and  mines  in  the  province  of 
Bergamo,  Italy.  The  Swansea  works  treat  ores  bought 
in  the  open  market  as  well  as  thosefrom  the  company's 
mine.  During  recent  years  money  has  been  spent  on 
new  properties  in  North  Wales  and  Tunis,  but  neither 
has  proved  a  success.  The  report  for  1910  shows 
that  the  mine  produced  10,260  tons  of  calamine  and 
blende  suitable  for  direct  calcining  and  roasting,  and 
in  addition  12,072  tons  of  ore  was  dressed  yielding 
3033  tons  of  calamine  and  blende  concentrates.  The 
net  profit  for  the  year  was  /20.120.  out  of  which 
/5068  has  been  added  to  the  reserve,  bringing  that 
fund  to  ;f  10,000,  /12,600  has  been  distributed  as  divi- 
dend, being  at  the  rate  of  15%,  and  the  balance  carried 
forward.      E.  Windsor  Carlvie  is  manager  of  the  mine. 

McKinley-Darragh-Savage.— This  company  owns 
property  at  Cobalt,  Ontario.  The  McKinley-Darragh 
mine  is  on  the  southwest  shore  of  Cobalt  lake,  and 
the  Savage  is  farther  to  the  south,  on  Cart  lake.   P.  A. 


80 


THE    MINING    MAGAZINE 


Robbins  is  manager,  and  the  offices  are  at  Toronto, 
and  Rochester,  N.Y.  In  our  issue  of  June  1909  we 
gave  a  history  of  the  venture  and  recorded  that  the 
production  of  silver  for  that  year  was  nearly  double 
that  for  1908.  The  report  for  1910  now  published 
shows  that  the  production  has  doubled  once  more,  the 
yield  of  silver  being  2,639,544  oz.,  as  compared  with 
1,297,326  oz.  in  1909,  718,068  oz.  in  1908,  707,543 
oz.  in  1907,  and  42,673  oz.  in  1906,  the  first  year  of 
operations.  During  1910,  57,653  tons  of  ore  was 
raised  at  the  McKinley-Darragh  mine,  of  which 
26,820  tons  was  waste,  and  the  remainder  sent,  to- 
gether with  6183  tons  from  the  dump,  to  the  mill. 
The  production  was  as  follows  ;  Nuggets  containing 
12,871  oz.  silver  ;  303  tons  of  first  class  ore  containing 
671,168  oz.  ;  386  tons  of  jig  concentrate  containing 
741,859  oz.  ;  725  tons  of  sand  containing  589,062  oz.  ; 
669  tons  of  slime  containing  179,639  oz.  ;  and  124  tons 
of  fine  containing  32,167oz.  ;  making  a  total  of  2210 
tons  containing  2,226,766  oz.  The  ore  reserve  on 
December  31  was  estimated  at  104,450  tons  containing 
4,894,000  oz.  silver.  It  is  proposed  to  strip  the  sur- 
face of  overburden  at  the  most  promising  points  in 
order  to  prospect  for  other  veins.  The  general  out- 
look at  the  mine  continues  excellent.  At  the  Savage 
property  10,583  tons  was  raised,  of  which  4312  tons  was 
rejected  as  waste.  Theremaindertogetherwith  295  tons 
from  the  dumps  went  to  the  mill  at  wliich  15,170oz.  sil- 
ver was  recovered  in  nuggets  together  with  the  follow- 
ing :  137  tons  of  No.  1  ore  containing  303,828oz.  silver ; 
58  tons  of  jig  concentrate  containing  81,421  oz.  ;  and 
20  tons  of  sand  containing  12,356  oz.  ;  making  a  total 
of  217  tons  containing  412,775  oz.  silver.  The  estima- 
ted value  of  the  silver  recovered  at  the  two  mines  was 
$1,426,856  and  the  cost  of  mining  and  concentration 
was  $254,794.  The  charges  at  the  smelter  were 
$124,596  and  other  expenses  and  allowances  for  de- 
preciation were  $70,824,  leaving  a  proSt  of  $976,640 
for  the  year.  The  report  does  not  state  how  much 
of  this  profit  was  distributed  as  dividend. 

Buffalo. — This  mine  is  situated  in  the  centre  of  the 
Cobalt  silver  district,  Ontario,  and  has  paid  dividends 
since  1906.  It  is  not  one  of  the  largest  producers,  but 
on  the  other  hand  is  notable  as  being  the  first  to  apply 
the  cyanide  process  for  the  treatment  of  fine  sand  and 
slime.  The  report  for  the  year  ended  April  30  shows 
that  the  output  and  shipments  were  much  the  same  as 
in  the  previous  twelve  months.  The  mining  develop- 
ments would  have  been  expanded  if  it  had  not  been  for 
the  difficulty  of  obtaining  compressed  air  from  the 
power  companies,  During  the  year  33,705  tons  from 
the  mine  and  7779  tons  from  the  dump  was  sent  to  the 
mill,  where  the  following  were  produced  :  25,795  oz. 
silver  in  nuggets,  540,078  oz.  in  jig  concentrate, 
632,202  oz.  in  table  concentrate,  and  103,321  oz.  in 
cyanide  bullion,  a  total  of  1,301,396  oz.  or  87%  of  the 
estimated  content.  The  cyanide  bullion  was  produced 
from  11,700  tons  of  slime  averaging  13  oz.  per  ton,  and 
67%  of  the  content  was  recovered.  The  shipments 
during  the  year  were  1079  tons  of  concentrates  and 
126 J  tons  of  high-grade  ore.  The  revenue  from  the 
sale  of  silver  was  $829,191  and  of  cobalt  $146,  a  total 
of  $829,337.  From  this  the  cost  of  freight  and  treat- 
ment, $75,115,  was  deducted,  leaving  an  income  of 
$754,221.  The  expenses  were  $343,297  leaving  a  profit 
of  $412,889  out  of  which  $370,000  was  distributed  as 
dividend  and  tlie  remainder  carried  forward  The 
amount  of  ore  developed  during  the  year  was  approxi- 
mately equal  to  that  mined.  In  the  concentration  plant, 
additional  tables  have  been  provided  for  treating  the 
slime  before  cyanidation.  The  cyanide  plant  is  being 
doubled,  and  within  a  short  time  all  the  fine  sand  and 


slime  averaging  over  6  oz.  will  be  treated.     Tom  R, 
Jones  is  the  manager. 

Nipissing. — This  is  one  of  the  largest  producers  of 
silver  at  Cobalt,  Ontario.  The  report  for  1910  shows 
an  increase  of  $480,000  in  the  profits  as  compared 
with  1909.  As  only  half  of  the  property  has  been 
prospected  it  is  probable  that  the  life  of  the  mine  will 
continue  for  a  considerable  period.  During  the  year 
the  following  shipments  were  made  :  1531  tons  of 
high-grade  ore  containing  3,999,580  oz.  silver,  4834 
tons  of  low-grade  silicious  ore  containing  1 ,008,357  oz. 
silver,  319  tons  of  concentrate  containing  296,490  oz. 
silver,  and  nuggets  containing  293,350  oz.  The  total 
production  was  5,597,778  oz.  valued  at  $2,991,891,  as 
compared  with  4,646,876  oz.  worth  $2,395,430  during 
1909.  In  addition  $16,109  was  received  as  credit  for 
cobalt  content.  The  cost  at  the  mine  was  $816,9x0, 
and  deductions  for  cc'St  of  treatment  by  smelters  to- 
gether with  freight  was  $264,692,  lea\ing  a  net  profit 
of  $2,167,103,  out  of  which  $2,100,000  has  been  dis- 
tributed as  dividend.  On  December  31  the  ore  reserve 
was  reported  to  contain  6,553,880  oz.  silver,  a  higher 
figure  than  a  year  ago.  This  does  not  take  into  account 
the  large  amount  of  milling  ore  on  the  dumps.  Much 
trenching  work  has  been  done  during  the  year,  and 
experiments  in  connection  with  hydraulically  stripping 
the  surface  have  also  been  undertaken  It  is  intended 
to  continue  the  laiter  work  and  additional  plant  for 
the  purpose  will  be  provided  during  the  present 
summer.  The  report  mentions  that  a  trial  plant  has 
been  erected  by  Charles  Butters  for  the  production  of 
silver  bullion  from  the  ore,  and  that  the  results  are 
most  encouraging. 

Zeehan  Montana. — This  mine  was  floated  in  1892 
as  a  subsidiary  of  the  Mount  Zeehan  (Tasmania) 
Silver  Lead  Mines  Co.,  and  for  many  years  did  well. 
In  1908,  however,  all  the  available  ore  appeared  to 
have  been  exhausted,  but  as  the  manager,  John  Craze, 
and  the  Oovernment  geologists  were  of  opinion  that 
further  exploration  work  was  warranted,  developments 
were  vigorously  prosecuted.  Success  rewarded  Mr. 
Craze's  efforts  and  the  results  for  1909  were  encourag- 
ing. The  report  for  1910  now  issued  shows  that  the 
orebodies  discovered  during  the  previous  year  have 
continued  to  yield  ore,  and  it  has  been  possible  to  pay 
a  dividend  once  more,  though  only  a  small  one,  at  the 
rate  of  2^%  on  a  capital  of  /80,006.  During  the  year, 
2908  tons  of  shipping  ore  was  raised,  and  10,316  tons 
of  concentrating  ore  averaging  11%  lead  and  11  oz. 
silver  per  ton  ;  of  the  total  product,  2603  tons  of  ore 
and  concentrate  was  shipped  to  Antwerp,  a\eraging 
65%  lead  and  88  oz.  silver,  and  333  tons  was  sold  to 
the  Tasmanian  Smelting  Co.,  averaging  62%  lead  and 
53^  oz.  silver  per  ton.  It  will  be  remembered  that  a 
year  ago  a  tin  property  was  bought  cheaply  for  cash 
in  the  adjoining  Dundas  tin  district.  Much  explora- 
tion work  has  since  been  done,  and  it  is  reported  that 
the  lode  is  large.  Unfortunately,  though  there  are 
rich  patches  here  and  there,  the  average  grade  is  low. 
Mr.  Craze  estimates  the  developed  ore  at  200,000  tons 
averaging  04%  metallic  tin,  but  he  doubts  its  profit- 
ableness. The  accounts  for  1910  show  receipts  from 
the  sale  of  ore  /36,126,  mine  expenses  ^28,289,  ad- 
ministration in  Tasmania  and  London  ;^4075,  and  other 
small  items,  leaving  a  net  available  profit  of  ;f3171  out 
of  which  /2000  was  distributed  as  dividend. 

Briseis. — This  company  was  formed  in  1899  to 
acquire  a  tin-gravel  property  in  the  Ringarooma  dis- 
trict in  the  northeast  of  Tasmania,  and  shortly  after- 
ward a  part  share  was  acquired  in  the  adjoining  New 
Brothers  Home  No.  1,  the  Briseis  company  working 
the  property  for  58%  of  the  net  produce.     In  1909,  as 


JULY,    1911 


81 


the  properties  were  approaching  exhaustion,  the  name 
of  the  company  was  changed  to  the  Briseis  Tin  & 
General  Mining,  and  gold-gravel  properties  in  Victoria 
were  acquired.  The  report  now  issued  covers  the 
year  1910  and  shows  that  in  June  the  No.  1  property 
and  the  southern  part  of  the  Briseis  were  finally  ex- 
hausted. In  1909  the  monthly  production  was  92  tons 
of  black  tin.  This  fell  to  67  tons  during  the  first  half 
of  1910  and  to  47  tons  during  the  second  half.  On 
December  31  it  was  estimated  that  the  Briseis  still 


No.  1  Co.  and  48J  that  of  the  Briseis.  The  revenue 
from  the  sale  was /77, 982  or  /161.  15s.  per  ton.  as 
compared  with  ;^105,953  or  £l38  per  ton  in  1909. 
As  regards  the  Wallace  gold-gravel  properties  in  Vic- 
toria, the  report  shows  that  the  old  dredges  are  just 
paying  their  way  with  a  small  output  of  /7972  for 
the  year,  and  that  of  the  two  new  dredges  one  is  al- 
ready at  work  and  the  other  should  be  ready  shortly. 
The  accounts  of  the  Briseis  Co.  for  1910  show  a  pro- 
fit of  /32,125  and  dividend  distribution  of  ^'30,000. 


.  Rai  I  way 


contained  enough  gravel  to  yield  45  to  50  tons  jDer 
month  for  three  years.  Work  has  proceeded  steadily 
with  the  removal  of  overburden  at  the  Ringarooma 
property  that  was  formerly  supposed  to  be  unprofit- 
able, but  no  further  information  has  been  obtained  re- 
lative to  the  tin  content  of  the  underlying  gravel. 
The  total  production  of  black  tin  during  1910  was  684 
tons  as  compared  with  1102  tons  in  1909,  and  the  cor- 
responding figures  for  metallic  tin  were  491  tons  and 
808  tons.     Of  the  491   tons,  9  was  the  share    of  the 


Utah  Copper. — The  net  profits  for  the  year  ended 
December  31,  1910,  amounted  tof5,401,:75.  Of  this 
sum  $3,890,912  was  the  profit  resulting  from  the  oper- 
ation of  the  plants  in  Utah.  After  the  payment  of 
dividends  aggregating  »4, 648, 675,  together  with  in- 
terest on  a  few  outstanding  bonds,  $187,  or  a  total  of 
$4,648,863,  there  remained  a  balance  for  the  year  of 
$752,912,  which  was  passed  to  undivided  profits.  The 
total  amount  standing  as  a  credit  to  undivided  profits 
on  December  31  last  amounted  to  $3,696,539,  and  is 


82 


THE    MINING    MAGAZINE 


the  amount  o\er  and  above  dividends  and  interest 
charges  which  has  been  derived  from  operating  profits 
and  income.  The  surplus,  $6,083,980,  is  the  amount 
received  in  cash  from  the  sale  of  stock  in  excess  of  the 
par  value  thereof.  On  December  31,  1909,  the  issued 
capital  stock  was  734,375  shares.  On  December  31, 
1910,  the  total  issued  capital  stock  was  1,562.599 
shares,  an  increase  during  the  year  of  828,224.  This 
increase  was  due  to  the  acquisition  of  the  Boston 
Consolidated  Mining  Co.'s  property,  in  exchange  for 
310,000  shares;  that  of  1,000.152  shares  of  stock  of 
the  Nevada  Consolidated  Copper  Co.,  444,512  shares; 
sales  for  cash  at  S50  per  share,  73.437  shares  ;  and 
conversion  of  bonds.  The  total  authorized  stock  of 
the  company  is  2,500,000  shares.  Quarterly  dividends 
were  paid  during  the  year  at  the  rate  of  |3  per  share 
per  annum.  The  total  length  of  all  underground  work 
up  to  the  end  of  1910,  was  6378  miles,  of  which  there 
is  now  accessible  4335  miles.  During  the  year  six- 
teen drill-holes  were  driven,  the  total  number  of  feet 
drilled  being  6209,  making  a  total  of  all  drilling  for 
development  purposes  on  the  property  of  10,015  ft. 
The  cost  of  underground  development  for  the  year 
amounted  to  702  c.  per  ton  on  all  ore  mined  and 
shipped  to  the  mills.  The  total  area  of  fully  and 
partly  developed  ground  was  166' 15  acres  The  aver- 
age thickness  of  the  developed  and  partly  developed 
ore  in  this  area  is  345  ft.  The  entire  orebody  has 
been  re-blocked  and  sectionalized,  and  the  tonnages 
and  values  re-calculated  upon  a  basis  that  is  as  definite 
and  accurate  as  the  character  of  the  orebody  permits. 
After  deducting  all  ore  mined  up  to  January  1,  1911, 
there  remains  in  the  area  in  which  the  principal  de- 
velopment has  been  done,  203,500,000  tons  of  fully 
and  partly  developed  ore.  Ofthisamount  152,130,000 
tons  are  fully  developed  and  blocked.  In  calculating 
ore  tonnages,  13  cu.  ft.  of  ore  in  place  is  taken  as  one 
ton.  Of  the  fully  developed  ore,  60,000,000  tons  has 
an  average  copper  content  of  2%,  and  the  remaining 
92,130,000  tons  of  ore  fully  developed  contains  1'6% 
copper.  The  average  assay  of  the  partly  developed 
ore  is  1'4%  copper.  The  entire  203,500,000  tons  de- 
veloped and  partly  developed  ore  contains  an  average 
of  1  67%  copper.  In  obtaining  these  averages,  there 
have  been  used  the  samples  from  225,722  ft.  of  drifts, 
rises,  winzes,  and  drill-holes,  the  total  number  of 
samples  taken  being  27,186.  As  a  check  against  the 
average  percentages  of  copper  stated,  it  is  interesting 
to  note  that  the  average  assay  of  the  total  11,175,916 
tons  of  ore  mined  and  milled  from  the  Utah  and  Bos- 
ton groups,  prior  to  the  date  of  this  report,  was  164% 
copper.  It  is  estimated  that  in  the  extraction  of  the 
entire  ore  reserve  stated,  the  average  copper  content 
will  fall  possibly  as  low  as  16%.  The  average  thick- 
ness of  capping  is  105  ft.,  or  a  ratio  of  ore  to  capping 
of  approximately  3  3  tons  of  ore  to  one  ton  of  capping. 
During  the  year  1910  the  total  capping  removed 
was  2.814,764  cu.  yd.  The  total  capping  removed  to 
January  1,  1911,  was  7,162,556  cu.  yd.  The  total  area 
upon  which  stripping  operations  have  been  conducted 
on  both  groups,  and  which  is  therefore  either  wholly 
or  partly  stripped,  is  85  acres.  The  actual  area  com- 
pletely stripped  on  both  groups  is  20  87  acres.  The 
total  yardage  removed  from  both  areas  represents  the 
equivalent  of  completely  stripping  41 '67  acres  of  cap- 
ping, ot  the  average  thickness  previously  stated,  for 
the  combined  groups.  Such  an  area  would  contain 
56,252,643  tons  of  ore.  The  amount  of  ore  removed 
from  the  mines  is  approximately  one-fifth  of  this  ton- 
nage. Of  the  total  ore  mined  during  the  vear,  82% 
was  mined  by  steam-shovels,  and  18%  by  underground 
methods.     The  average  cost  of  mining  for  the  year 


was  4097  c.  per  ton,  of  which  13 '3  c.  was  charged  to 
cover  development  and  stripping  expense,  leaving  a 
total  cost  for  producmg  ore  of  27'67  c.  per  ton.  The 
total  cost  of  producing  20%  of  underground  ore  was 
appro.ximately  the  same  as  that  of  producing  the  other 
80%  by  steam-shovel  methods.  The  total  tonnage 
treated  at  all  plants  for  the  year  was  4,340,245.  The 
average  grade  of  the  ore  treated  at  all  plants  was 
r54%  copper,  and  the  average  extraction  at  all  plants 
6655%,  equivalent  to  a  recovery  of  2051  lb.  of  cop- 
per per  ton  of  ore.  The  average  cost  of  milling  for 
all  plants  for  the  year  was  46'63  c.  per  ton,  including 
proper  proportions  of  all  fixed  and  general  charges. 
The  total  produdion  of  all  plant  for  the  year,  of  cop- 
per contained  in  concentrate,  was  89,019.511  lb.  The 
average  grade  ol  concentrate  produced  was  2728% 
copper.  The  a\erage  price  received  for  copper  sold 
during  the  year  was  12  672  c.  per  lb.  The  average 
cost  per  pound  of  copper  produced,  based  on  the  net 
pounds  of  copper  resulting  after  smelting  deductions 
and  allowances  were  made,  and  after  applying  credits 
for  the  gold  and  silver  recovered,  was  8  069  c.,  as 
compared  to  8  787  c.  for  the  year  1909.  This  cost 
includes  all  expenses  of  smelting,  refining,  transporta- 
tion, and  selling  the  metal.  The  average  cost  of  pro- 
duction at  the  Magna  plant  for  the  period,  and  on  the 
same  basis,  was  78828  c.  per  pound.  The  cost  of  min- 
ing and  milling, exclusive  of  transportation,  was  87'6c., 
as  compared  with  94  43c.  for  the  previous  year. 

TRADE    NOTES 

Most  of  the  trade  publications  mentioned  in  this 
column  are  available  for  distribution  and  the 
manager  of  "  The  Mining  Magazine  "  will  be 
pleased  to  secure  copies  for  persons  interested 

A.  C.  Wells  &  Co.  describe  their  acetylene  lamps 
in  a  six-page  ftjlder. 

The  Alexander  Milburn  Co.  send  us  a  48-page 
catalogue  describing  their  various  types  of  acetylene 
lamps.  The  reader  cannot  help  but  be  impressed 
with  the  splendid  array  of  letters  from  satisfied  users. 

Bowes,  Scott  &  Western  devote  a  special  folder  to 
the  description  of  their  sand  and  slime  pumps.  The 
special  features  mentioned  are  the  simplicity  and  easy 
access  to  wearing  parts. 

International  Channelling  Machines,  Ltd.  ha\e  is- 
sued a  catalogue  describing  the  Siskol  Stope  Drill. 
This  drill  tied  for  first  place  in  the  recent  South  African 
tests,  and  received  a  prize  of  /2500.  A  short  and  in- 
teresting summary  is  given  of  the  drill  trials.  The 
makers  give  full  details  of  the  construction  and  action 
of  the  drill,  and  the  purpose  of  the  catalogue  is  evi- 
dently to  give  every  facility  to  the  possible  user  to 
study  each  feature  of  the  machine.  Very  few  cata- 
logues give  such  complete  information. 

The  Bucyrus  Co.'s  Placer  Dredge  Catalogue  (8  by 
11  in.,  86  pages)  makes  good  reading.  The  generous 
size  of  the  pages  allows  large  photographs  to  be  re- 
produced without  obscuring  the  details  of  construction 
Well  executed  line  drawings  give  a  good  idea  of  the 
general  arrangement  of  the  operating  and  gold-saving 
machinery.  An  imposing  list  appears  of  80  dredges 
equipped  with  Bucyrus  machinery.  It  is  interesting 
to  note  that  the  Continental  Dredge  in  Oroville  built 
in  1899  and  still  in  commission,  was  the  first  of  the 
close-connected  bucket  tvpe  now  almost  universally 
adopted  on  American-built  dredges  It  is  claimed 
that  one  of  the  Bucyrus  15  cu.  ft.  dredges  has  dug 
325,000 cu.  yd.  in  one  month  and  averaged  275,000  per 
month  for  one  vear. 


1*^ 


The  Mining  Magazine 


Vol.  V. 


LONDON,   AUGUST    1911. 


No.  2 


Scientia  non   habet  inimicum  nisi  ignorantem. 


T.    A.    RICKARD,    Editor.  EDGAR    RICKARD,    Business  Manager. 

PUBLISHED  BY  THE  MINING  PUBLICATIONS  LTD.,  at  819  SALISBURY  HOUSE,  LONDON.  E.C 

Issued   on    the    15th   day   of   each    month. 

Telegraphic  Address  :    Oligoclase.     Codes  :  McATe/W,  both  editions.     Telephone:    8938   London    Wall. 

Branch  Offices  : 
SAN  FRANCISCO:  420  MARKET  STREET.     CHICAGO:  934  MONADNOCK  BUILDING.      NEW  YORK:  29  BROADWA 

Agents  for  the  Colonies  : 
GORDON    &    GOTCH,    LONDON,    MELBOURNE,    Etc.    (SOUTH    AFRICA:    CENTRAL    NEWS    AGENCY.    LTD.) 

Registered  with  the  G.P.O.  for  transmission  to  Canada  by  Canadian  Magazine  Post. 


SUBSCRIPTION    RATES. 

United  Kingdom  and  Canada,  12  Shillings  (Single  Copy,  Is.)    ...    Abroad,  16  Shillings  (Single  Copy,  Is.  4d.) 


CONTENTS. 


PAGE 

Review  of  Mining 84 

Statistics  of  Production 92 

Editorial 

Notes 93 

Finches  and  Finance 97 

Impoverishment  in  Depth 98 

Results  on  the  Rand 100 

The  Porcupine  Fire. 101 

Coast  Erosion 102 

Bendigo    104 

Special  Correspondence 

Juneau 105 

Toronto 108 

San  Francisco 1 09 

Johannesburg 1 10 

Mexico 112 

Melbourne 114 

Camborne 116 

New  York 117 

Metal  Markets 120 

Personal 138 


PAGE 

Articles 

The  Pyrites  Deposits  of  Huelva  

H.  F.  Collins   121 

The  Finance  of  a  Mine.   Ill 

M.  H.  Burnham   125 

Mining  in  Rhodesia F.  P.  Mennell  132 

Ball-Mill  Practice  at  Kalgoorlie 

M.  W.  von  Bsrnexvitz   139 

Precis  of  Technology 

Shaft  Sinking  in  Wet  Ground 147 

Extraction    of    Mercury    from    Low- 
grade  Cinnabar  Ores  148 

Mine  Temperatures 148 

Steel  Production  of  the  World 148 

Determining  Copper  in  Pyrite 148 

Slime  Settlement  149 

Specular  Iron-Ore  in  Iluel\a 149 

The  Gold  Industry  of  the  Rand 150 

Current  Literature 152 

Books  Reviewed 153 

Company  Reports 155 

Trade  Notes  160 


REVIEW    OF    MINING 


Introductory.  —  The  hot  weather,  the 
summer  hohdays,  the  Moroccan  crisis,  and 
the  domestic  pohtical  situation  have  had  a 
cumulative  effect  in  causing  stagnation  in  the 
mining  markets.  But  conditions  are  healthy. 
Money  is  plentiful,  good  news  has  preponder- 
ated over  discouraging  items,  and  the  techni- 
cal position  is  excellent.  Even  mines  that  are 
shaky  are  being  supported  by  plucky  share- 
holders, so  that  bear  raids  are  highly  danger- 
ous.    No  large  bull  accounts  exist. 

At  the  end  of  July  some  uneasiness  was 
caused  by  rumours  affecting  the  Yorkshire 
Penny  Bank.  This  old  and  reputable  savings 
bank  was  in  a  bad  way.  Only  the  prompt  in- 
tervention of  the  Bank  of  England  prevented 
a  collapse  that  would  have  caused  an  unplea- 
sant shock,  coming  so  soon  after  the  Birkbeck 
failure.  However  the  situation  was  saved, 
fresh  capital  was  provided,  and  serious  trouble 
averted. 

The  Kaffir  market  continues  sluggish.  De- 
creased dividends  have  discouraged  investors. 
Some  of  them  feel  that  they  get  too  little  con- 
sideration from  the  big  operators.  Business 
is  more  evident  in  Rhodesians,  which  are  sub- 
ject to  moderate  fluctuations.  This,  however, 
is  no  investor's  market ;  it  offers  a  lively  gam- 
ble to  the  cheerful  plunger  and  to  the  well  in- 
formed speculator.  West  Africans  are  dull, 
pending  actual  results  from  new  plants.  Bro- 
ken Hill  shares  have  attracted  attention  and 
dealings  have  been  lively, especially  in  British, 
South,  and  Block  14.  Porcupine  issues  have 
been  depressed  by  the  fire,  but  interest  in  this 
new  goldfield  has  spread  and  several  important 
houses  have  sent  engineers  to  investigate. 

Transvaal. — The  statistics  for  June  en- 
able us  to  compare  the  first  half  of  1911  with 
the  same  period  of  1910,  the  total  yield  of  gold 
being  worth  ^16,889,615,  which  is  ;^  1,382,277 


or  8i%  more  than  in  the  corresponding  period 
last  year.  The  July  statistics  are  noteworthy 
as  the  monthly  output  has  for  the  first  time 
exceeded  700,000  m  ounces  and  300,000  in 
pounds  sterling  ;  the  exact  figures  being 
709,258  oz.  and  /■3,012,738,  of  which  679,881 
oz.  came  from  the  Rand  and  29,377  from 
elsewhere.  Up  to  the  end  of  June  the  gold 
production  of  the  Transvaal,  since  1884,  had 
reached  the  gigantic  total  of  ^"337,102, 700  or 
one  quarter  of  the  world's  production  dur- 
ing the  entire  27  years.  It  is  interesting  to 
note  that,  according  to  the  report  of  the  State 
Mining  Department,  the  development  work 
done  in  the  mines  of  the  Transvaal  in  May 
aggregated  no  less  than  97,490  feet  or  more 
than  18  miles  of  underground  working.  Only 
9000  feet  is  credited  to  mines  outside  the 
Rand.  An  mcrease  in  rock-drills  is  shown, 
the  number  being  4201  as  against  3851  in 
January.  The  tonnage  hoisted  was  2,517,136. 
The  millingequipment  is  represented  by  10,095 
stamps  and  225  tube-mills,  of  which  9470 
stamps  and  212  tube-mills  are  within  the 
Rand  area.  The  base-metal  production  in 
May  amounted  to  352  tons,  worth  ^59,402, 
as  against  ;^32,508  in  January. 

These  statistics  are  all  satisfactory  and  the 
only  item  to  check  optimism  is  the  decline  in 
the  supply  of  labour.  During  June  the  de- 
crease was  3447,  that  is,  from  209,196  to 
205,749  natives.  This  came  on  top  of  a  de- 
crease of  3936  in  May.  Now  we  have  the 
figures  for  July,  showing  a  further  loss  of 
4991,  so  that  the  total  is  200,758  natives,  as 
compared  with  the  201,672  employed  at  the 
same  date  last  year.  The  fluctuation  is  nor- 
mal, but  it  is  apparent  that  the  efforts  to  re- 
cruit a  larger  supply  have  availed  but  little. 
An  increased  demand  is  faced  with  a  supply 
that  is  practically  unchanged.     Reasons  for 


84 


AUGUST,    1911 


85 


this  shrinkage,  apart  from  the  seasonal  migra- 
tion, were  given  in   these  pages  last  month. 

During  the  first  half  of  1911  the  mines  of 
the  Witwatersrand  yielded  11,444,176  tons 
from  which  a  profit  of  ;^5,643,148  was  ob- 
tained. During  the  same  period  the  dividends 
aggregated  ;^4,084,817.  In  1910  the  total 
profit  was  /"l  1,216,105  and  the  total  divi- 
dends /8,875,000.  This  suggests  that  the 
term  'profit'  is  generous  ;  in  other  words,  that 
only  80%  of  the  so-called  '  profit '  reaches  the 
shareholders.  Some  of  the  20%  is  expended 
in  improvements,  in  plant  and  machinery,  in 
bonuses  to  directors,  in  sundry  and  extraor- 
dinary expenses,  but  these  expenditures  are 
just  as  essential  as  the  money  spent  in  labour 
and  advice,  fuse  and  caps,  postage  and  sta- 
tionery. 

In  the  latter  part  of  July  a  flutter  was 
caused  by  the  Johannesburg  correspondent  of 
The  Financial  Times  cabling  that  several  of 
the  Eckstein  mines  would  revert  from  electric 
power  to  steam.  This  seemed  a  curious  re- 
action and  elicited  a  prompt  correction  from 
the  Central  Mining  office.  It  appears  that 
the  supply  of  electric  power  is  inadequate 
owing  to  the  increased  substitution  of  electric 
for  steam  power  ;  at  the  same  time  the  supply 
of  compressed  air  from  the  Rand  Mines  Power 
Supply  Co.,  to  the  mines  controlled  by  the 
Rand  Mines  Ltd.,  has  been  delayed  by  the 
non-completion  of  the  entire  plant,  but  the 
4000  hp.  compressors  at  work  are  doing  ex- 
cellent service.  As  Mr.  George  Albu  only 
recently  stated  at  the  New  Goch  meeting  that 
the  saving  through  the  adoption  of  electric 
power  as  against  steam  was  7'28  pence  per 
ton  milled  it  would  indeed  be  surprising  if  this 
line  of  progress  were  to  be  abandoned. 

The  Brakpan  figures  for  July  were  well  re- 
ceived. The  yield  and  profit  are  both  good, 
and  the  latter  will  be  better  when  the  cost  be- 
comes normal.  The  estimate  of  ore  in  reserve 
is  also  excellent,  showing  distinct  gains  both  in 
quantity  and  quality. 


Rhodesia.— The  British  South  Africa  Com- 
pany gives  50,890  ounces,  worth  £2\5,'i^7, 
as  the  gold  production  in  June.  This  is  a 
slight  increase  as  compared  with  May,  but 
less  than  March  and  April.  For  the  six 
months  the  total  output  was  ^1,290,961  as 
against  ;^1, 327,591  in  the  first  half  of  1910. 
Among  the  various  productive  mines  the  Globe 
&  Phoenix  holds  first  place  with  10,401  oz. 
from  6501  tons,  this  being  a  slight  gain.  The 
Rhodesian  Corporation  and  the  Selukwe  Col- 
umbia also  exhibited  improvement  in  June. 

In  the  latter  part  of  July  the  Rhodesian 
market  was  cheered  by  excellent  news  from 
the  Shamva,  Lonely,  and  Eldorado  mines. 
The  manager  of  the  Shamva  cabled  that  five 
feet  of  4  oz.  ore  had  been  cut  in  a  drift  on  the 
second  level,  besides  other  high-grade  ore  else- 
where on  the  same  level.  This  points  to  a 
considerable  sweetening  of  the  low-grade  stuff 
on  which  the  enterprise  is  founded.  At  the 
Lonely  Reef  the  sixth  level  is  showing  well 
as  compared  with  the  fifth,  and  the  lode 
has  been  cut  on  the  seventh,  exposing  4i  feet 
of  2  oz.  ore.  The  new  plant  also  started  on 
July  1st,  so  that  bigger  returns  may  be  ex- 
pected. At  the  Eldorado  Banket  mine  the 
bottom  or  eighth  level  is  full  of  promise,  an 
assay  of  5  oz.  for  a  width  of  6  ft.  being  an- 
nounced at  the  place  where  the  lode  was  first 
cut.  This  has  been  confirmed  by  a  later 
cablegram,  indicating  that  the  rich  ore  con- 
tinues and  shows  visible  gold  freely. 

Shareholders  in  mining  companies  who  re- 
ject the  advice  of  their  consulting  engineers 
deserve  scant  sympathy.  We  have  none  for 
the  speculators  in  Selukwe,  for  they  persisted 
in  spending  money  in  further  development 
after  Messrs.  A.  H.  Ackermann  and  H.  Ewer 
Jones  had  plainly  advised  them  to  desist. 
The  Selukwe  has  given  many  unnecessary 
spasms  to  the  share  market ;  its  obsequies 
call  for  no  further  delay. 

A  good  impression  was  made  by  the  publi- 
cation of  an  estimate  of  ore  in  reserve  in  the 


86 


THE     MINING     MAGAZINE 


Globe  &  Phoenix  mine,  the  figures  being 
179,040  tons  averaging  36  dwt.  on  June  30, 
as  against  181,137  tons  averaging  35'2  dwt. 
on  March  31.  The  sinking  of  the  explora- 
tory winze  from  the  16th  to  the  18th  level  is 
to  be  resumed. 

Census  returns  show  that  the  white  popu- 
lation of  Southern  Rhodesia  is  23,582,  as 
against  12,596  in  1904.  Salisbury  has  3479 
and  Bulawayo  5200  inhabitants.  In  the  whole 
of  Rhodesia  about  20,000  white  men  control 
the   industrial   activity  of   2,000,000  natives. 

On  August  10  the  manager  of  the  Tangan- 
yika Concessions  sent  a  cablegram  concerning 
the  trial-run  with  the  first  blast-furnace.  Some 
copper  is  being  produced,  under  difficulties. 
Until  detailed  information  is  available,  it  is  im- 
possible to  conclude  whether  the  experiment  is 
a  success. 

West  Africa. — The  output  of  gold  for 
June  was  22,555  ounces,  worth  ^'92,174,  this 
being  a  slight  decrease  on  May  but  still  far 
above  the  average.  The  total  for  the  half- 
year  is  111,688  oz.  valued  at  ^456,324  as 
compared  with  185,493  oz.,  worth  ;^755,985, 
for  the  whole  of  1910.  The  increase  is  note- 
worthy, but  less  than  might  have  been  ex- 
pected. In  June  the  Prestea  duplicated  its 
May  output,  although  a  larger  return  was  ex- 
pected. The  Ashanti  Goldfields  is  still  easily 
the  chief  producer,  with  ^41,360  worth  of 
gold  from  9933  tons. 

Our  information  from  the  Gold  Coast  in- 
dicates that  the  Prestea  has  had  a  series  of 
troubles  and  that  its  estimated  prosperity  may 
be  further  delayed.  Even  the  50  stamps  have 
not  been  continuously  employed  and  it  is  un- 
likely that  ore  for  the  full  complement  of  110 
stamps  can  be  furnished  for  some  time  to 
come.  The  vein  has  a  graphitic  casing  on  the 
hanging  wall  ;  this  comes  away  when  the 
quartz  is  broken  and  necessitates  a  tedious 
process  of  filling,  for  which  proper  facilities 
have  not  been  provided.  The  failure  of  the 
supply-pump  on  the  river  caused  some  annoy- 


ance and  a  miscalculation  in  the  capacity  of 
the  electric  motors  has  resulted  in  an  over- 
heating that  entails  interruptions  to  regular 
work.  At  the  Taquah  and  Abosso  mines  a 
distinct  improvement  is  reported,  the  co-op- 
eration of  Messrs.  J.  W.  Newberry  and  W. 
R.  Feldtmann  having  given  a  better  tone  to 
the  entire  administration.  The  managers  of 
the  two  mines,  namely  L.  C.  Stuckey  and  G. 
C.  Campion,  are  highly  regarded  by  those  on 
the  spot. 

A  good  report  concerning  the  Ancobra 
dredging  enterprise  is  brought  by  Mr.  S.  J. 
Weis,  recently  appointed  manager.  He  finds 
that  the  present  dredges  are  poorly  adapted 
for  local  conditions  and  that  the  ground  has 
been  worked  without  system,  but  that  the 
gravel  is  rich.  Part  of  the  property  is  virgin 
and  invites  the  application  of  up-to-date  me- 
thods, while  even  the  ground  that  has  been 
partly  turned  over  may  contain  enough  gold 
to  be  worth  re-working.  A  vigorous  cam- 
paign of  drilling  is  now  in  order,  previous  to 
erecting  a  new  dredge  suitable  for  West  Afri- 
can conditions.  Apparently  in  this  case  some 
time  and  gold  have  been  wasted,  but  it  is  not 
too  late  to  retrieve  the  position. 

Australia, — OurMelbournecorrespondent 
sends  an  interesting  account  of  the  Tanami 
goldfield,  with  comments  on  the  Chillagoe  and 
Mount  Elliott  copper  enterprises. 

The  directors  of  the  Broken  Hill  Block  10 
have  decided  to  spend  ir20,000  in  remodelling 
the  lead-concentration  plant,  which,  though 
doing  excellent  work,  is  not  so  modern  as  those 
at  the  North  and  South  mines.  The  manager 
of  the  North  mine,  Mr.  George  Weir,  was 
asked  to  advise  in  collaboration  with  the  man- 
ager, Mr.  V.  F.  Stanley  Low,  and  he  has 
made  recommendations  that  should  save  an 
additional  ^20,000  per  annum.  It  is  only  a 
few  months  since  the  company  discarded  the 
newly  erected  Elmore  plant  used  for  the  treat- 
ment of  the  zinc  tailing,  and  decided  to  ship 
the  material  to  the  De  Bavay  plant  instead. 


AUGUST,    1911 


87 


Mr.  Weir's  services  appear  to  be  much  in  de- 
mand ;  he  is  also  advising  Block  14  with  re- 
gard to  the  design  of  a  plant  for  treating  the 
low-grade  sulphide  still  in  the  mine. 

The  action  brought  by  the  Elmore  com- 
panies in  the  New  South  Wales  court  against 
the  Sulphide  Corporation  for  damages  on  ac- 
count of  the  use  by  the  latter  of  the  Minerals 
Separation  process  has  been  dismissed.  An- 
nouncement is  made  that  the  Elmore  com- 
panies are  appealing  to  the  Judicial  Committee 


and  four  more  died  in  hospital.  The  staff  of 
John  Taylor  &  Sons  and  the  Government  in- 
spectors, headed  by  Mr.  W.  F.  Smeeth,  have 
for  years  been  making  enquiries  into  these 
'air-blasts,'  and  though  some  are  eventually 
found  to  be  ordinary  falls,  many  others  are 
undoubtedly  to  be  attributed  to  the  release  of 
pressure  from  schist  m  a  state  of  internal 
strain.  How  to  prevent  or  predict  such  acci- 
dents is  more  than  they  have  been  able  to 
ascertain.     The  most  serious  occurred  three 


DREDGING  ON  THE  ANGOBIiA  RIVER,   WEST  AFRICA. 


of  the    Privy    Council    in    London,   for   final 
settlement  of  the  dispute. 

India. — The  accident  that  occurred  at  the 
Champion  Reef  mine  on  July  25  draws  atten- 
tion once  more  to  the  '  air-blasts '  that  are 
comparatively  common  in  the  Kolar  district, 
especially  at  this  particular  mine.  Stoping 
was  being  done  at  the  22nd  level  north  of  Car- 
michael's  shaft,  a  comparatively  shallow  part 
of  the  mine.  A  large  number  of  natives  were 
at  work  and  the  sudden  disaster  buried  several 
and  hurt  others.      Fifteen  were  killed  outright 


years  ago  at  1098  ft.  during  the  sinking  of  the 
new  circular  shaft,  a  special  report  on  the 
subject  having  been  made  and  published  by 
Mr.  Smeeth  at  the  time. 

United  States. — We  publish  a  letter 
from  Juneau,  Alaska,  written  by  a  particu- 
larly w^ell  informed  correspondent  and  giving 
the  latest  news  from  that  part  of  the  world. 
Our  San  Francisco  and  New  York  correspon- 
dents refer  to  copper  operations.  We  note  also 
that  the  Calumet  &  Hecla  mining  conipany  has 
issued,  for  the  first  time,  a  tabulated  comparison 


88 


THE    MINING    MAGAZINE 


of  results,  from  which  it  appears  that  in  1910 
the  mine  yielded  72,059,545  lb.  copper  from 
2,795,514  tons  of  ore.  The  yield  was  2577 
lb.  per  ton  or  r28%  copper.  The  total  cost 
of  this  copper  was  8"96  cents  per  pound  and 
the  price  received  was  13"20  c.  per  pound. 
The  yield  of  copper  was  31  "22  lb.  per  ton  of 
ore  in  1908  and  28T8  lb.  in  1909.  Ten  years 
ago  it  was  60  pounds. 

In  Colorado  a  systematic  effort  is  being 
made  to  stimulate  prospecting,  the  Denver 
Chamber  of  Commerce  having  raised  a  fund 
of  $10,000  by  popular  subscription.  This  is 
the  basis  for  a  '  Grubstake  &  Development 
Company  '  capitalized  for  $2,000,000.  Great 
efforts  are  being  made  at  Leadville  and  at 
Silverton  to  beneficiate  low-grade  zinc  ores. 
.A  revival  in  placer  mining,  especially  in  Sum- 
mit county,  has  followed  successful  dredging 
near  Breckenridge.  Rich  gravel  is  claimed 
also  to  have  been  found  in  Newlin  gulch,  in 
the  valley  of  Cherry  creek,  where  gold  was 
first  found  in  Colorado  in  1852. 

Canada.  —  The  fire  at  Porcupine,  which 
raged  fiercely  for  three  days,  did  not  depress 
shares  in  local  mines  as  much  as  might  have 
been  expected.  This  w'as  due  to  the  prompt 
action  of  the  stock-exchanges  at  Toronto  and 
Montreal,  which  were  closed  from  the  12th  to 
the  17th  of  July.  Selling  at  New  York  caused 
some  declines,  now  mostly  recovered.  Hol- 
linger  fell  at  one  time  to  $10*75,  for  it  was 
natural  that  those  mines  nearest  to  the  pro- 
ductive stage  should  be  most  injured  by  the 
disaster.  Mere  prospects  have  not  much  plant 
to  lose.  Cats  proverbially  have  nine  lives; 
wild-cats  are  even  tougher.  At  Porcupine 
they  were  barely  singed.  Undoubtedly  the 
biggest  loss  was  at  the  Dome  mine,  where  a 
first-rate  mill,  nearly  completed,  was  destroyed. 
This  mill  would  have  enabled  the  Dome  to 
make  a  noteworthy  production,  of  great  ser- 
vice to  the  reputation  of  the  district.  We  are 
glad  to  learn  that  the  Bewick-Moreing  camps 
were  saved.     A  relief  committee  is  now  hard 


at  work  ;  already  35  search  parties  have  been 
sent  out  to  aid  disabled  persons,  the  area  swept 
by  the  fire  covering  a  tract  nearly  30  miles 
square.  Both  of  the  railway  stations,  at  Kelso 
and  Cochrane,  were  burnt,  but  this  has  not 
stopped  the  train  service.  It  is  stated,  m 
London,  that  two  new  issues  are  impending, 
both  of  them  to  be  launched  by  the  Timmins 
syndicate.  One  is  called  the  Dixon,  with  a 
capital  of  $5,000,000,  and  the  other  the  Miller- 
Middleton,  with  a  capital  of  $3,000,000.  Both 
properties  are  near  the  Hollinger. 

Announcement  is  made  that  the  Consoli- 
dated Gold  Fields,  through  its  subsidiary 
American  company,  has  acquired  a  large 
holding  in  the  Yukon  placer  enterprise  origin- 
ated by  Mr.  A.  N.  C.  Treadgold  and  financed 
in  part  by  Messrs.  H.  C.  Hoover  and  A. 
Chester  Beatty.  We  made  reference  to  this 
business  in  our  April  issue.  The  property 
comprises  10,000  acres  of  alluvial  ground  in 
the  Klondike  valley,  near  Dawson,  and  in  the 
district  rendered  famous  by  the  great  rush  of 
1  898,  and  later  by  the  Guggenheim  operations 
under  the  title  of  the  Yukon  Gold  Company. 
In  this  connection  it  becomes  interesting  to 
note  that  the  Yukon  Gold  Co.  in  1910  pro- 
duced gold  to  the  value  of  $2,847,098.  The 
annual  report  states  that  the  7  dredges  handled 
3,249,788  cubic  yards  during  a  season  of  159 
days,  producing  $2,150,723  or  66*18  cents 
per  yard,  at  a  total  cost  of  31 '090.  per  cu.  yd. 
This  includes  thawing,  which  cost  14'6c.  per 
cu.  yd.,  and  other  preliminary  outlay.  The 
hydraulic  mining  and  mechanical  elevators 
moved  705,544  cu.  yd.  for  a  yield  of  $696,375 
or  987c.  per  yd.,  at  a  cost  of  25*69c.  per  cu. 
yd.  These  figures  do  not  include  the  royal- 
ties paid.  Apparently  the  mming  profit  w^as 
$1,655,471.  On  turning  to  the  original  pros- 
pectus, issued  early  in  1908,  we  find  that  the 
profit  predicted  for  1910  was  $2,500,000.  At 
the  time  when  the  Yukon  Gold  was  floated, 
the  cost  of  dredging  was  estimated  by  IVIessrs. 
O.  B.  Perry  and  A.  C.  Beatty  at  30c.,  with  a 


AUGUST,    1911 


89 


profit  of  39c.  These  figures  compare  well  with 
the  accomplishment  today.  At  the  same  time 
and  by  the  same  engineers  the  cost  of  work- 
ing the  hill  gravel  was  put  at  lOc,  with  a 
profit  of  22c.  p3r  cu.  yd.  Owing  to  the  use 
of  mechanical  elevators  in  the  creek-bottom 
and  the  mixing  of  the  results  with  those  ob- 
tained from  hydraulicking  the  bench-gravel, 
it  is  not  possible  to  make  a  comparison  with 
the  original  estimate,  but  the  combined  cost 
of  25"69c.  and  the  combined  yield  of  98'7c. 
seem  to  justify  the  technical  forecast,  except 
as  to  the  quantity  of  gravel  exploited.  If  the 
Yukon    Gold  had  been   properly   capitalized 


The  unrest  among  labourers  is  natural,  for 
now  that  Diaz  is  gone  they  feel  that  they  may 
assert  themselves  with  impunity.  Several 
strikes  have  ensued.  They  are  being  quieted. 
On  August  1  the  managers  of  the  three 
principal  mines  at  El  Oro  telegraphed  to  say 
that  operations  were  stopped  bya  riotof  miners 
on  strike,  aided  by  prisoners  released  from 
the  gaol.  Foreign  residents  sent  their  women- 
folk to  Mexico  City  by  train.  Next  day  it 
was  announced  that  the  military  were  in  con- 
trol, the  mills  were  still  running,  but  that  the 
mines  were  idle.  Since  then  order  has  been 
completely  restored  and  all    the   mines   are 


PIPE-LINK  OF  THE  YUKON  GOLD  CO.  CAllHIED  ON  A  BRIDGE  ACROSS  THE  KLONDIKE  RIVER. 


and  if  in  its  infancy  it  had  not  suffered  from 
an  attack  of  whooping  cough  due  to  a  certain 
Thomas  W.  Lawson  of  Boston,  it  would  to- 
day rank  as  a  most  creditable  performance. 

The  sale  of  the  Le  Roi  mine  to  the  Con- 
solidated Mining  &  Smelting  Company  of 
Canada  for  $250,000  closes  a  disagreeable 
chapter  in  British  mining  enterprise.  The 
smelter  at  Northport  remains  in  the  possession 
of  the  liquidator. 

Mexico. — Our  correspondent  sends  inter- 
esting items  concerning  the  oil  companies. 
The  revolution  is  having  its  effects  on  conces- 
sions, and  on  labour.  The  grant  of  blanket 
concessions  may  have  helped  individual  oper- 
ators but  it  has  tended  to  hinder  prospecting. 
2—2 


again  in  full  operation. 

The  Mexico  Mines  of  El  Oro  issues  the 
manager's  annual  report,  from  which  it  ap- 
pears that  the  mine  is  in  a  healthy  condition, 
the  reserve  having  been  increased  35,000  tons 
without  diminution  in  grade.  The  gross  out- 
put is  $1,528,229  from  136,408  tons  as  against 
$1,392,336  from  136,372  tons  last  year. 

Esperanza  shareholders  have  been  cheered 
by  news  of  a  discovery  in  a  cross-cut  ex- 
tended westward  on  the  lowest  or  11th  level 
of  the  mine.  After  passing  through  the  San 
Rafael  lode  another  new  vein  was  cut,  carry- 
ing five  feet  of  ore  assaying  26  dwt.  gold  and 
4  oz.  silver  per  ton.  A  drift  has  been  started 
both  ways  and  is  in  good  ore.     Going  south 


90 


THE  MINING  MAGAZINE 


the  boundary  of  the  Ofir  claim  is  near,  but 
northward  there  is  plenty  of  room — 1500  ft. — 
for  important  developments.  At  Pachuca, 
the  Santa  Gertrudis  mill  is  now  running  at 
nearly  full  capacity,  50  stamps  dropping  out  of 
60.  Mine  developments  continue  satisfactory. 
It  is  noteworthy  that  A.  Goerz  &  Co.,  a 
firm  prominent  in  South  African  mining,  has 
opened  an  office  at  Mexico  City,  placing  Mr. 
Cyrus  T.  Pott  in  charge. 

Siberia. — Washing  of  gold-bearing  gravel 
is  proceeding  satisfactorily  at  the  mines  of 
the  Lenskoie,  the  Russian  company  in  which 
the  Lena  Goldfields  hold  a  controlling  in- 
terest. Up  to  July  20  the  yield  has  been 
255,615  oz.  gold  from  504,172  cubic  yards  of 
gravel.  Last  year  at  this  time  the  produc- 
tion was  250,624  oz.  from  427,378  yards.  An 
interim  dividend  of  3s.  per  share  has  been  de- 
clared, and  it  is  expected  that  another  of  equal 
amount  will  follow  the  annual  meeting  in  No- 
vember. 

At  the  Orsk  Goldfields  the  Pokrovsky  wash- 
ing-plant has  been  winning  gold  at  the  rate  of 
a  pennyweight  per  cubic  yard,  a  result  that  is 
encouraging,  if  it  can  be  ascertained  beyond 
doubt  that  this  is  a  fair  sample  of  the  ground. 
Mr.  C.  H.  Munro,  the  new  manager,  has 
started  drilling  and  pit-sinking  on  a  large 
scale,  so  that  any  doubt  should  soon  be  re- 
moved or  confirmed. 

The  directors  of  the  Troitzk  Goldfields  have 
followed  the  example  set  by  the  Orsk  Gold- 
fields  in  raising  fresh  capital  by  an  issue  of 
104,993  priority  shares,  increasing  the  nomi- 
nal capital  to  ;^625,000.  It  is  estimated  by 
this  company's  consulting  engineers,  Messrs. 
Hooper,  Speak  &  Feilding,  that  a  working 
profit  of  not  less  than  ;^39,658  per  annum  is 
assured,  provided  their  scheme  of  develop- 
ment and  equipment  is  adopted. 

Various. — The  injury  to  mining  done  by 
Central  American  revolutions  is  suggested  by 
the  report  of  the  Oroya  Leonesa  company, 
from  which    it   appears    that    their   mine   in 


Nicaragua  has  suffered  delay  both  in  develop- 
ment and  equipment,  necessitating  the  pro- 
vision of  additional  capital.  The  mine  itself 
seems  to  promise  well  and  now  contains  94,400 
tons  of  ore  averaging  39'7s.  per  ton,  besides 
lower- grade  stuff. 

The  directors  of  the  Maikop  Spies  company 
show  commendable  restraint  in  referring  to 
the  prospects  of  the  Maikop  oilfield  ;  in  their 
first  annual  report  they  state  that  develop- 
ment "  has  been  delayed  by  the  difficulties 
invariably  met  with  in  a  remote  and  virgin 
country.  .  .  .  The  geological  conditions  differ 
markedly  from  those  of  the  other  great  Rus- 
sian fields,  volcanic  influences  having  appar- 
ently produced  great  irregularities  in  the 
strata.  .  .  .  Meanwhile  it  has  been  proved 
by  ourselves  and  other  companies  that  large 
quantities  of  oil  exist  in  certain  sections."  It 
is  two  years  since  British  capital  was  attracted 
to  the  Kuban  province,  now  famous  as  Mai- 
kop, and  much  money  has  been  subscribed. 
Dividends  are  lacking  as.  yet,  but  oil  is  being 
produced  and  marketed ;  as  shown  in  the 
articles  published  by  us,  real  progress  is  being 
made  and  active  prospecting  by  drilling  is 
under  way.  The  dimensions  of  the  produc- 
tive area  should  be  ascertained  by  the  end  of 
the  current  year. 

The  Oroville  Dredging  Co.  has  finally  ob- 
tained the  transfer,  from  the  American  com- 
pany, of  the  Pato  dredging  concession  in  Col- 
ombia. A  delay  of  two  years  in  concluding 
the  deal  was  caused  by  the  insistence  of  the 
vendors,  who  take  25%  of  the  shares  in  the 
new  company,  and  demanded  an  agreement 
that  no  change  of  capitalization  or  other  lia- 
bility could  be  incurred  without  the  consent 
of  90%  of  all  the  shareholders.  Mr.  H.  S. 
Derby,  representing  the  vendors,  won  his 
point,  after  much  delay.  Meanwhile  $325,000 
has  been  advanced  by  the  Oroville  company 
and  a  dredge  is  being  completed,  with  the  ex- 
pectation of  beginning  to  dig  in  January. 
Everything  points  to  a  successful  enterprise. 


AUGUST,    1911 


91 


The  ground  is  rich  and  the  operations  are  in 
the  hands  of  experienced  men  from  California. 
The  Oroville  has  a  good  chance  of  being  re- 
juvenated by  this  expansion  into  Colombia. 

Silver. — Miners  in  Mexico,  for  instance, 
may  not  be  aware  that  the  price  of  silver  is 
affected  by  the  Indian  monsoon,  yet  it  is  a 
fact  that  the  market  is  sensitive  at  this  time 
to  the  news  regarding  the  rainfall.  As  mon- 
soon prospects  in  India  are  good,  the  price  of 
silver  has  risen  to  241  pence  per  ounce. 


the  producers  throughout  the  world  are  at  their 
maximum  output,  and  there  is  little  likelihood 
of  any  important  new  sources  of  supply.  The 
Conventions  that  regulate  the  outputs  and 
prices  are  in  consequence  assuming  a  firm 
attitude,  and  users  exhibit  nervousness  as  to 
the  future.  These  conditions  are  the  cause 
of  the  vitality  shown  by  Broken  Hill  shares 
on  the  Stock  Exchange  to  which  we  refer 
elsewhere. 

Owners  of  properties  containing  complex 


ROUND  THE  SAMOVAR.     A  SCENE  IN  SIBERIA. 


Tin  mines  have  continued  to  attract  atten- 
tion, especially  in  the  Malay  States.  Results 
encourage  speculation,  especially  at  the  Tronoh, 
which  announces  a  profit  of  ^53,500  for  July. 
The  output  during  that  month  was  635  tons 
of  concentrate,  valued  at  ^72,000,  with  a 
working  cost  of  ;^  18,500.  For  the  last  three 
months  the  company  has  earned  a  profit  of 
^^143, 100  on  its  nominal  capital  of  ;^160,000. 
The  rainy  season,  now  impending,  will  curtail 
production. 

Lead  and  Zinc. — Present  conditionspoint 
to  the  approach  of  a  period  of  high  prices  in 
lead  and  zinc.  Trade  throughout  Great  Bri- 
tain and  the  Continent  is  excellent,  and  so  the 
demand  is  increasing.     On  the  other  hand,  all 


or  low-grade  ores  are  naturally  reviewing  the 
altered  position  as  it  affects  them.  The  con- 
trolling Conventions  however  have  such  a 
power  for  raising  and  lowering  prices  that 
financiers  are  not  quite  convinced  of  the  de- 
sirability of  embarking  any  large  amount  of 
money  in  these  new  ventures. 

Copper. — The  statistics  of  the  American 
Copper  Producers  Association  indicate  that  in 
July  the  production  decreased  12,386,000  1b. 
as  compared  with  June,  and  that  the  stock  of 
metal  in  hand  at  the  end  of  the  month  had  de- 
clined 19,695,000  lb.  Thus  the  production  is 
the  smallest  this  year,  excepting  February, 
while  the  deliveries  for  export  are  the  largest. 
Only  the  domesticdeliveries  are  disappointing. 


92 


THE  MINING  MAGAZINE 


STATISTICS 

Stocks  of  Copper  in  England  and  the  Continent. 
Reported  by  Henry  R.  Merton  &  Co. 


May  31. 
Tons 

June  30 
Tons 

July  31 
Tons 

57,557 
6,081 
2,200 
6,775 

55,579 
5,843 
1,500 
7,250 

53,807 

In  France  

5,893 

Afloat  from  Chile 

2,075 

Afloatfrom  Australia 

6,250 

Total  

72,613 

7,250 
10,500 

70,172 

7,200 
10,100 

68,025 

In  Rotterdam. 

7  550 

In  Hamburg  (estimated)... 

10,400 

American  Copper  Producers'  Association. 
In  Tons  of  2,240  lb. 


January  1911. 
February    .... 

March 

April 

May 

June 

July  


Produc- 
tion. 


51,650 
49,030 
58,273 
52,716 
56.679 
55,605 
50,075 


Deliveries 


Domes- 
tic 


18,785 
22,553 
29,500 
23,396 
28,814 
27,525 
25,438 


Foreign 


23,753 
20,139 
26.375 
27,736 
27,669 
31,902 
33,429 


Total 


42,538 
42.692 
55,875 
51,132 
56,483 
59,427 
58,867 


Stocks  at 
end  of 
month 


63,591 
69,929 

72,325 
73,909 
74,105 
70,283 
61,491 


Production  of  Gold  in  the  Transvaal. 


July,  1910  ... 

August  

September 

October 

November 
December.. 


Totals,  1910., 

January  1911 

February  

March  

April  

May     

June    , 

July 


Rand 


Oz. 
610,664 
623,129 
621,311 
627,445 
617,905 
616,668 


7,228,588 

625,862 
585,683 
649,247 
638,421 
658,196 
657,023 
679,881 


Else- 
where 


Total 


Oz. 

28,050 
26,140 
25,588 
25,702 
24,686 
24,327 


305,532 

25,201 
24,965 
26,818 
29,293 
27,755 
27,544 
29,377 


Oz. 

638,714 
649,269 
646,899 
653,147 
642,591 
640,995 


7,534,120 

651,027 
610,828 
676,065 
667,714 
685,951 
684.567 
709.258 


Value 


£ 

2,713.083 
2,757,919 
2,747,853 
2,774,390 
2,774,390 
2,722,775 


32,002,912 

2,765,386 
2,594,634 
2,871,740 
2.836,267 
2,913,734 
2,913,734 
3.012,738 


Cost  and  Profit  on 

THE  Rand. 

Month. 

Tons 

Yield 
per  ton 

Costs  i    Profit        Total 
per  ton  1  per  ton       profit 

January  1911... 
February 

1,865,232 
1,712,198 
1 ,960,678 
1,926,583 
2,002,926 
1,986,559 

s.    d. 

26  6 
28    0 
28    6 

27  7 
27    7 
27    6 

s.    d. 

17  11 

18  3 
17  11 
17    6 
17  10 
17  11 

s.    d.            £ 

10    1    j    930.059 

10    3    1    874.612 

9    9   '    949.415 

10     1       971.858 

9     7       956.823 

9     8  !    960.381 

March  

April 

May 

June  

Totalsand  aver- 
ages for  1909.. 
Ditio  1910 

20.543,759 
21.432,541 

28  11 
28    6 

17     1    1    11     6   1  11,794,376 
17     7        10    6   j  11,216.105 

Natives  Employed  in  the  Transvaal  Mines. 


January  31.. 
February  28 
March  31  ... 

April  30 

May  31  

June  30 

July  31 


Gold 

mines 


183.268 
189.434 
193,457 
194,328 
190,392 
186.940 
181.582 


Coal 
mines 


1.357 
1.513 
1.493 
1.511 
1.379 
1.212 
1.122 


Diamond 
mines 


9.991 
9,814 
10,061 
10,272 
10,425 
10,597 
11,054 


Total 


201,616 
207,761 
212.011 
213,111 
209,196 
205,749 
200,758 


Gold  Output  of  India. 

Year  1909 

Year  1910 

July  1911 

1911  to  date 

^2 ,083 .901 

£2,104,858 

£179.558 

£1,231,880 

Production  of  Gold  in  Rhodesia. 


Month. 

1908 

1909 

1910 

1911 

£ 

199,388 
191,635 
200,615 
212,935 
223,867 
224,920 
228,151 
230.792 
204.262 
205.466 
196,668 
217.316 

£ 

204,666 
192,497 
202,157 
222,700 
225,032 
217,600 
225,234 
228,296 
213,249 
222,653 
236,307 
233,397 

£ 

227.511 
203.888 
228.385 
228.213 
224.888 
214,709 
195.233 
191,423 
178.950 
234.928 
240.573 
199.500 

£ 

207,903 
203,055 
231,947 
99^    ''Qf\ 

February  

March   

211.413 
215.347 

July 

September  ... 

October 

November 

December..  ■ 

— 

Totals 

2,526,007 

2,623.788 

2.568,201 

— 

Production  of  Gold  in  West  Africa. 


Month. 

1909 

1910 

1911 

Oz. 

Value 

Oz. 

Value 

Oz. 

Value 

January  

February    .. 

March 

22.817 
21.403 
23.186 
21.491 
25,104 
17,340 
17.331 
17.766 
18,125 
15,957 
17,882 
17,570 

£ 

91,112 
86,210 
93,556 
88,071 
100,056 
70.561 
70.523 
71,614 
72,963 
65,813 
73,824 
71,332 

17,357 
16,976 
17,627 
16,363 
16,590 
17,194 
15,564 
13.921 
11,497 
13,341 
14,021 
15.042 

£ 
70,699 
68,469 
71.954 
67,069 
68,355 
70,988 
58,551 
57,713 
47,746 
55,046 
57,658 
61.737 

15,903 
15.179 
16,387 
17,237 
24,427 
22,555 

£ 
66.107 
63.081 
67.673 
70  880 

May 

96,409 
92,174 

July  

August  

September... 

October  

November ... 
December  ... 

— 

235,972 

955.635 

185,493 

755.985 

1 

Production  of  Gold  in  Western  Australia. 


Month. 

Export 
oz. 

Mint 
oz. 

Total 
oz. 

Total 
value 

Total,  1910  

363,496 

1,209,856 

1.573,352 

£ 

6,682,042 

January  1911  

17,463 
22,047 
12,296 
20,455 
22,076 
10.523 
15.334 

102,035 
84,991 
93,267 
91,791 
88,952 

106,464 
97,387 

119,498 
107,038 
105,563 
112,246 
111,028 
116,987 
112,721 

507,592 

February    

454,666 

March         

448,426 

April            

476.787 

May              

471,615 

497  188 

lulv                    

478.805 

Other 

Australasian  Gold  Production 

1909 

1910 

July 
1911 

1911 
to  date 

£ 

1.916.468 

869.546 

2.006,910 

2,897,340 

£ 

1,840,337 

803,727 

1,896,322 

2,422,700 

143,500* 

56,517 

199,246 

190,894 

£ 

783,810* 

New  South  Wales 

New  Zealand 

Victoria 

432,791 
1,081,366 
1,224,600 

*  June  figures  only. 
Sale  of  Tin  Concentrate  at  Redruth  Ticketings. 


June  12,  1911 

June  26,      „ 

July  10,      „ 

July  26.      „ 


Tons 


221i 
269^ 
213i 
2541 


Value 


£26,403 
£31,399 
£25,019 
£28,484 


Average 


£I19     1  5 

£ll6  10  2 

£117    6  5 

£lll  16  3 


E.\poRTs  OF  Tin  and  Ore  from  Straits  and  Bolivia. 
Reported  by  A.  Strauss  &  Co. 


Metal  from  Straits  to  Europe 
and  America   

Metallic  Content  from  Bolivia 
to  Europe 


June,  1911 
tons 

5,060 

2,056 


July  1911 
tons 

4555 

2332 


1911  to  date 
tons 

30,117 

13,005 


EDITORIAL 


AT  THE  TIME  of  writing,  London, 
Liverpool,  and  other  centres  of  industry 
are  on  the  verge  of  paralysis  by  reason  of  a 
widespread  strike,  started  by  workers  at  the 
docks.  How  far-reaching  its  eflfects  may  be 
is  suggested  by  the  fact  that  milling  at  the 
Mountain  Queen  mine  in  Western  Australia 
will  be  postponed  at  least  three  months  by 
reason  of  the  inability  of  the  mail  steamers  to 
take  the  heavy  machinery  required  to  complete 
the  plant. 


IN  REFERENCE  to  the  note  in  our  last 
issue  concerning  the  unpleasant  incident  at 
the  Kyshtim,  we  are  informed  that  the  Syssert 
estate  was  at  one  time  under  option  to  the 
Anglo-Siberian  Co., and  that  this  option  passed 
later,  on  different  terms,  to  the  Russian  Min- 
ing Corporation.  This  explains  the  little  feel- 
ing that  may  have  been  at  the  bottom  of  the 
misunderstanding.  The  visiting  engineers 
were  in  the  employ  of  the  Russian  Mining 
Corporation,  while  the  resident  engineers  were 
acting  under  orders  from  a  company  that  is  a 
subsidiary  of  the  Anglo-Siberian  company.  It 
was  not  a  simple  case  of  withholding  techni- 
cal information. 


EARLY  in  August  our  friend  the  Mining 
and  Scientific  Press  moved  from  667 
Howard  street  to  new  quarters  at  420  Mar- 
ket street,  San  Francisco.  The  offices  on 
Howard  Street  were  in  a  temporary  structure 
erected  after  the  earthquake-fire  and  repre- 
sented a  makeshift  during  the  period  of  re- 
organization. The  new  quarters  are  close  to 
the  spot  where  the  Press  was  housed  before 
the  disaster  of  April  18,  1906,  and  on  the 
main  thoroughfare  of  San  Francisco.  The 
oldest  mining  paper  in  America  has  been  tried 
in   the  fire  and   found   not  wanting;    it   was 


shaken  by  the  earthquake  and  stood  firm  ;  it 
has  shared  the  manifold  life  and  development 
of  the  Pacific  Coast  region,  and  while  it  has 
had  to  move  more  than  once,  it  has  always 
moved  on  and  moved  upward.  We  shake 
hands  with  our  friends  on  the  other  side  of 
the  world  and  wish  them  continued  success. 


GEOLOGICAL  THEORIES  are  rarely 
of  such  economic  importance  as  those 
that  correlate  the  various  systems  of  gold- 
bearing  banket  in  the  Transvaal.  Our 
readers  will  have  heard  that  Mr.  W.  E.  Bleloch 
has  undertaken  to  combat  accepted  views  and 
has  issued  a  treatise,  with  a  map,  to  expound 
his  own  notions  on  the  subject.  These  are 
worthy  of  respectful  consideration  ;  therefore 
we  take  pleasure  in  publishing,  elsewhere  in 
this  issue,  a  review  by  Mr.  S.  J.  Truscott,  who 
is  well  qualified  to  express  the  orthodox  opinion 
on  this  scientific  problem. 


AMONG    DEEP    MINES    the    Morro 
Velho  of  the  St.  John  del   Rey  com- 
pany, in  Brazil,  is  interesting,  not  least  be- 
cause it  pays  its  shareholders  a  regular  divi- 
dend.    The  company  was  organized  in  1830 
and  has  undergone  reconstruction   twice,   in 
1887  and  1888.     In  a  recent  issue  we  gave  a 
cross-section  of  the  mine  showing  the  workings 
to  have  reached  a  vertical  depth  of  4926  feet, 
equivalent  to  7000  ft.  on  the  dip  of  the  lode. 
At  that  depth  ventilation  is  well  maintained, 
but  the  health  of  the  miners  sufiers  owing  to 
their  being  subjected  to  a  great  variation  of 
temperature,  from  95°  F  underground  to  70°  at 
surface.     The  rock  is  dry  and  the  men  suffer 
much  from  the  inhalation  of  dust.    Apart  from 
its  depth,  however,  the  Morro  Velho  is  remark- 
able, as  representing   the    life-work   of   Mr. 
George  Chalmers,  who  has  overcome  disasters 


93 


94 


THE    MINING    MAGAZINE 


and  difficulties  enough  to  dismay  any  but  the 
most  enterprising  and  courageous  of  men. 


WE  NOTE  with  pleasure  that  the  Uni- 
versity of  Minnesota  gives  its  fresh- 
men engineers  a  two-hour  course  in  English 
and  that  this  is  joined  to  a  two-hour  course 
in  practical  composition.  The  two  authors 
chieflystudiedareArnoldand  Huxley.  Sweet- 
ness and  Light '  followed  by  '  A  Piece  of 
Chalk  '  afford  models  of  thought  and  expres- 
sion well  fitted  to  stimulate  the  mind  of  a 
budding  engineer.  We  send  our  compliments 
to  the  faculty  of  the  University  of  Minnesota 
and  look  forward  to  the  time  when  our  col- 
umns will  be  enriched  by  observant  young 
men  trained  in  the  use  of  their  language, 
which  is  also  ours. 


THE  STORY  of  the  original  purchase  of 
the  Nipissing  from  the  prospector  who 
found  it,  seems  worth  telling,  as  obtained  from 
one  closely  associated  with  the  transaction.  In 
1901  the  son  of  Mr.  J.  P.  Earle  happened  to 
be  camping  and  fishing  on  Lake  Temiskaming 
when  some  prospectors  showed  him  specimens 
of  very  rich  silver  ore.  He  sent  them  to  his 
father  in  New  York  and  they  were  assayed, 
proving  of  phenomenal  richness.  Mr.  Earle 
had  just  made  a  good  turn  and  had  some  spare 
cash.  Taking  a  certified  cheque  with  him  he 
started  at  once  for  Ontario  to  see  the  find.  He 
estimated  that  if  the  pocket  of  ore  in  the  pros- 
pect hole  continued  ten  feet  deeper  he  would 
get  a  return  of  the  purchase  price  asked.  He 
accepted,  and  then  and  there  filled  out  the 
certified  cheque  for  the  amount.  His  first 
shipment  a  few  weeks  later  netted  $285,000 
or  considerably  in  excess  of  the  sum  paid. 
Thus  again  we  have  an  illustration  that  truth 
is  stranger  than  fiction,  for  some  of  the  mineral 
supposed  to  be  silver  was  probably  smaltite 
and  the  calculation  of  ten  feet  of  persistence 
might  just  as  well  have  been  based  on  a  hun- 
dred feet.     He  betted  on  a  contingency  that 


happened  to  be  more  than  fulfilled.  Thousands 
have  taken  similar  chances  but  so  unsuccess- 
fully that  the  facts  have  not  been  deemed 
worthy  of  record.  The  Nipissing  has  already 
paid  $6,500,000  in  actual  dividends,  nearly 
thirty  times  the  amount  paid  for  it. 


M 


UCH  TIME  is  wasted  in  the  city  of 
London  by  reason  of  errors  made  by 
telephone  operators.  It  is  not  too  much  to  say 
that  the  telephone  system  of  the  metropolis  is 
not  equal  to  that  of  a  second-rate  American 
town.  However,  when  the  transfer  of  the  sys- 
tem has  been  completed  to  its  new  owners, 
we  may  expect  an  improvement.  Blessed  are 
they  that  expect  nothing,  for  they  shall  not  be 
disappointed.  Meanwhile  we  would  suggest 
some  uniformity  in  the  etiquette  of  telephon- 
ing. When  Smith  wants  Brown,  Smith's 
clerk  rings  to  Brown's  clerk,  and  the  latter 
tells  him  to  put  Smith  on  the  line,  whereupon 
Smith  holds  the  telephone  awaiting  Brown's 
pleasure.  Brown  may  be  busy  and  the  call 
is  delayed  or  it  proves  abortive.  It  appears 
clear  that  the  man  who  initiates  the  call  must  be 
at  the  telephone  or  close toit, for  itwouldbeim- 
pertinent  for  him  to  'call  up'  a  friend  if  he  him- 
self isengaged  or  otherwise  unprepared  to  speak 
promptly.  On  the  other  hand  it  is  always  un- 
certain whether  the  man  called  is  free  to  talk. 
Therefore  it  should  be  unnecessary  to  require 
the  caller  to  hold  the  telephone  until  he  is  in- 
formed whether  his  friend  is  at  liberty.  Obvi- 
ously a  man  should  not  ask  another  to  come 
to  the  telephone  unless  he  himself  is  ready  to 
speak.  At  present  time  is  squandered  at  both 
ends  ;  it  seems  possible  to  save  it  by  a  little 
mutual  consideration. 


REFERRING  to  the  trial  of  the  Gie- 
secke  mill  at  Johannesburg,  we  are  in- 
formed that  after  the  inventor,  Mr.  Karl  Gie- 
secke,  left,  on  his  return  to  Brunswick,  the 
wear  and  tear  increased  enormously,  while 
the  capacity  of  the  mill  decreased.     From  an 


AUGUST,    1911 


95 


average  of  17  tons  per  hour  the  crushing  de- 
clined to  16  tons  per  hour  by  day  and  5i  tons 
per  hour  by  night.  These  figures  point  clearly 
to  incompetent  supervision  and  tend  to  em- 
phasize the  fact  that  in  the  use  of  machines 
of  this  kind  the  character  of  the  feeding  is 
decisive.  The  wear  of  balls  and  plates  was 
excessive  after  the  first  three  weeks  during 
which  the  inventor  superintended  the  test,  and 
an  effort  is  now  being  made  to  obtain  balls 
that  are  tough  not  only  as  regards  an  outer 
shell  but  throughout,  that  is,  not  merely  case- 
hardened  ;  otherwise  the  wear  becomes  rapid 
when  the  comparatively  soft  interior  is  ex- 
posed to  attrition.  However,  the  wear  on 
the  balls  in  the  Giesecke  mill  cannot  be  more 
severe  than  in  an  ordinary  ball-mill,  which 
does  not  give  excessive  trouble  on  this  score. 
The  large  balls  are  usually  made  of  forged 
steel,  and  manganese  steel  has  been  success- 
fully used  in  making  the  smaller  ones.  It  is 
obvious  that  the  Giesecke  trial  at  Johannes- 
burg will  draw  increased  attention  to  this  type 
of  pulverizer. 


this  smelting  enterprise  will  be  successful.  It 
serves  to  remind  us  of  a  curious  episode  in  the 
history  of  tin  mining  in  the  Far  East.  In  1903 
a  smelter  was  erected  at  Bayonne,  New  Jersey, 
with  the  avowed  purpose  of  treating  tin  con- 
centrate from  the  Straits  Settlements.  The 
American  syndicate  that  organized  the  enter- 
prise anticipated  obtaining  a  low  ocean  freight 
by  the  Standard  Oil  steamers  returning  from 
the  petroleum  markets  of  the  Far  East.  It 
was  also  expected  that  from  the  tin  thus  pro- 
duced it  would  be  convenient  to  make  tin-plate 
for  the  oil-cans ;  so  that  the  oil  industry  and 
the  tin  industry  would  prove  mutually  helpful. 
Unfortunately  in  June  of  that  year,  just  when 
the  Bayonne  smelter  was  ready  to  start  work, 
the  Government  of  the  Federated  Malay  States 
imposed  a  duty  of  .^30  per  picul  on  all  tin  ore 
exported,  thus  killing  the  American  enterprise. 
This  export  duty  should  now  be  a  source  of 
comfort  to  the  Eastern  Smelting  Company. 


INTEREST  in  tin  mining  within  the  Feder- 
ated Malay  States  has  been  stimulated  by 
the  high  price  of  tin  and  the  success  of  the 
Tronoh,  Gopeng,  and  other  British  undertak- 
ings. Therefore  the  formation  of  a  smelting 
company  is  quite  in  order.  The  one  in  ques- 
tion, called  the  Eastern  Smelting  Company, 
has  been  formed  to  acquire  from  the  Penang 
Company  the  smelting  business  purchased  three 
years  ago  from  Mr.  Lu  Chin  Ho,  one  of  the 
many  enterprising  Chinamen  who  have  taken 
a  prominent  part  in  the  Malay  tin  industry. 
The  directors  of  the  new  company  are  only 
three  in  number  but  they  should  constitute  an 
excellent  board,  including  as  they  do  the  late 
British  Resident  of  Perak,  a  partner  in  Vivian, 
Younger  &  Bond,  and  a  partner  in  Lake  & 
Currie.  Thus  the  executive  includes  an  ex- 
perienced administrator,  a  metal  broker,  and 
a  mining  engineer.    We  hope,  and  expect,  that 


AMONG  publications  furnishing  useful 
information  on  mining  and  metallurgi- 
cal progress  is  Mines  and  Methods,  a  monthly 
journal  published  at  Salt  Lake  City,  Utah. 
It  is  now  nearly  two  years  old  and  is  thus 
our  contemporary  in  the  literal  as  well  as  the 
literary  sense.  During  these  two  years  this 
Western  American  periodical  has  provided  a 
considerable  quantity  of  technical  informa- 
tion, which  would  have  inspired  greater  con- 
fidence if  obviously  it  had  not  been  used  chiefly 
as  a  stone  to  hurl  at  the  head  of  the  Utah 
Copper  Company.  Even  a  casual  glance  at 
the  pages  of  Mines  and  Methods  shows  that 
its  chief  purpose  is  to  attack  the  personnel  of 
the  management  controlling  the  biggest  cop- 
per enterprise  in  Utah.  This  vendetta  is  in- 
spired by  Colonel  E.  A.  Wall,  whose  Improved 
Ore  Jigger  also  furnishes  a  subject  for  the 
principal  page  of  advertisement.  Into  Colonel 
Wall's  quarrel  with  the  Utah  Copper  we  shall 
not  probe,  for  we  have  no  clear  notion  of  its 
underlying  cause,  any  more  than  that  which 


96 


THE    MINING    MAGAZINE 


prompted  the  violence  of  a  verbal  attack,  duly 
recorded  in  Mines  and  Methods,  made  by  the 
editor,  Mr.  Claude  T.  Rice,  against  Mr.  D.  C. 
Jackling,  the  general  manager  of  the  sup- 
posedly objectionable  company.  In  the  in- 
terests of  technical  journalism,  however,  we 
do  not  hesitate  to  say  that  technology  ought 
not  to  be  used  as  a  cloak  for  a  private  quar- 
rel. Notwithstandmg  the  obvious  merit  of 
many  of  Mr.  Rice's  writings  they  are  unre- 
liable for  the  simple  reason  that  so  many  of 
them  are  prepared  not  so  much  to  give  inter- 
esting technical  data  as  to  serve  as  a  catapult 
against  the  Colonel's  enemy  ;  in  short,  they 
are  not  trustworthy.  As  now  conducted  Mines 
and  Methods  ranks  with  a  broker's  circular  ; 
of  such  there  are  plenty. 


a  sincere  protest  or  an  interested  correction 
helps  us  onward  in  our  purpose,  which  is  to 
give  information  useful  to  those  engaged  in 
mining.  This  magazine  is  tied  by  no  strings 
save  the  cord  of  sympathy  with  all  those  that 
go  down  the  mine  in  skips.  We  welcome 
frank  discussion  at  all  times  and  we  take  this 
opportunity  of  thanking  Mr.  Mennell  for  so 
obvious  a  comprehension  of  the  spirit  that 
animates  our  work. 


IN  THIS  ISSUE  we  publish  an  interesting 
and  informing  article  on  mining  in  Rho- 
desia by  Mr.  F.  P.  Mennell.  This  contribu- 
tion is  the  outcome  of  a  friendly  controversy, 
Mr.  Mennell  having  taken  exception  to  some 
of  the  opinions  expressed  by  us  on  mining 
affairs  in  a  part  of  Africa  with  which  he  is  fami- 
liar. He  could  not  have  paid  this  magazine 
a  more  agreeable  compliment  than  first  to 
criticize  and  then  to  contribute.  Purely  de- 
structive criticism  is  rarely  useful,  although 
sometimes  amusing,  but  the  correcting  of  sup- 
posed errors  by  the  submission  of  authentic 
information  is  constructive  in  its  highest  sense. 
The  opinions  expressed  by  us  were,  we  believe, 
not  so  far  from  the  truth  as  Mr.  Mennell 
claims,  but  their  value  has  been  enhanced  by 
his  own  supplementary  statements.  Every 
subject  has  several  facets  ;  we  are  glad  when 
our  friends  draw  attention  to  such  aspects  as, 
for  lack  of  space  or  information,  we  may  ap- 
pear to  neglect.  It  cannot  be  said  too  fre- 
quently that  we  welcome  intelligent  criticism 
rather  than  idle  compliment.  No  man  and  no 
group  of  men  can  envisage  the  whole  of  a 
subject  so  broad  as  mining  in  its  worldwide 
aspect.     A  polite  Amen  leaves  us  as  we  were  ; 


OUR  READERS  will  have  seen  the 
newspaper  accounts  of  the  wreck  of 
the  Spokane  on  the  coast  of  British  Columbia 
on  June  29.  Only  three  passengers  lost  their 
lives,  but  among  these  was  the  wife  of  Mr. 
Gardner  Williams,  who,  with  her  husband, 
was  on  the  way  to  Treadwell,  Alaska.  They 
were  accompanied  by  Mr.  and  Mrs.  W.  W. 
Mein,  the  latter  being  a  daughter  of  Mr.  and 
Mrs.  Williams.  When  the  vessel  struck,  an 
inrush  of  water  swept  Mrs.  Williams  down 
the  gangway,  so  that  she  was  drowned.  An- 
other mining  engineer  well  known  to  the  pro- 
fession was  on  board  in  the  person  of  Mr. 
Philip  Argall,  who  was  accompanied  by  two 
of  his  daughters.  The  father  saw  them 
safely  in  a  lifeboat,  and  then  helped  the  other 
women  to  get  off.  As  the  last  boat  got  clear 
the  ship  listed  to  starboard  and  sank,  the 
lights  were  extinguished,  and  the  scene  was 
blotted  with  inky  darkness.  The  wreck  was 
only  300  yards  from  the  shore,  but  no  one  was 
aware  of  the  fact  and  no  one  had  the  sense  to 
light  the  lamps  in  the  life-boats.  Mr.  Argall 
climbed  into  the  rigging  as  the  steamer  set- 
tled in  the  shallow  water  above  a  sand  spit 
and  when  the  camp-fires  began  to  twinkle  on 
the  shore  he  swam  toward  them,  being  picked 
up  by  a  returning  lifeboat.  Thus  he  escaped 
and  both  of  the  daughters,  one  of  whom  had 
her  knee  dislocated.  The  Pacific  Coast 
Steamship  Co.,  the  owners  of  the  Spokane, 
returned  the  passage  money  but  refused  com- 
pensation   for    baggage  or   other  loss.     The 


AUGUST,    1911 


97 


ship  struck  a  rock  in  the  Seymour  Narrows 
at  11.15  p.m.  of  June  29  but  it  was  possible 
to  steer  her  into  the  quiet  waters  of  Plumpers 
Bay  before  she  sank.  On  board  there  were 
150  passengers  and  a  crew  of  80.  The  night 
was  dark,  the  passengers  remained  quiet  and 
self-possessed,  the  crew  were  largely  under 
the  influence  of  drink  and  made  a  sorry  exhi- 
bition. Unfortunately  the  steamers  plying 
along  the  coast  of  British  Columbia  and ' 
Alaska  represent  an  inferior  type,  most  of  the 
capable  and  energetic  avoiding  the  poor  pay 
and   restricted    quarters    of    a    small    vessel. 


The  wreck  of  the  steamer  Spokane  in  Plumpers  Bay.     Two 
lifeboats  in  attendance,  gathering  floating  baggage. 


The  Steamers  themselves,  with  a  few  excep- 
tions, are  quite  unworthy  of  the  regions  to 
which  they  carry  mails  and  supplies.  This 
is  all  the  more  regrettable  as  the  voyage  from 
San  Francisco  or  Seattle  to  Juneau  or  Valdez 
is  one  of  the  most  picturesque  and  interesting 
in  the  world. 


Finches  and  Finance. 

It  is  only  about  six  months  since  we  warned 
the  public  against  the  litter  of  wild-cats  let 
loose  from  Bullfinch  m  Western  Australia, 
yet  even  this  short  interval  has  been  enough 


to  give  regrettable  confirmation  to  the  antici- 
pations then  expressed.  The  abandonment 
or  liquidation  of  several  of  the  companies 
then  formed  has  been  announced  recently 
and  others  are  apparently  moribund.  The 
Bullfinch  East  company,  introduced  on  No- 
vember 9,  1910,  with  a  capital  of  ^120,000, 
without  an  engineer's  report,  but  with  shares 
at  a  premium,  is  now  to  be  liquidated.  The 
consulting  engineer,  engaged  after  the  flota- 
tion, not  before,  advises  that  "the  prospects 
do  not  warrant  further  expenditure  "  at  this 
alleged  gold  mine.  The  Bull  Ant  Proprietary 
was  issued  on  November  23,  1910,  "  with  a 
capital  of  ^200,000  and  a  few  general  state- 
ments of  an  unconvincing  character."  We 
quote  from  The  Mining  Magazine  of  De- 
cember 1910.  In  this  case  a  circular  has 
been  sent  to  the  shareholders  stating  that 
the  developments  upon  the  property  so  far 
do  not  justify  further  expenditure  upon  it  " 
and  offering  to  exchange  two  shares  of  Bull 
Ant  for  one  share  of  Bullfinch  Proprietary. 
The  shares  of  the  latter,  the  parent  of  the 
pups  that  made  such  a  splash  not  long  ago, 
are  now  quoted  at  about  15s.  as  against  the 
£?>\  to  which  they  were  hoisted  last  Decem- 
ber on  the  basis  of  information  that  may  indeed 
have  been  perfectly  honest  but  was  also  pal- 
pably prejudiced.  Meanwhile  the  Bullfinch 
Proprietary  has  proved  to  be  what  we  feared, 
a  patch  of  rich  ore  in  jasperoid  ironstone,  of 
a  character  similar  in  non-persistence  to  many 
others  found  in  Western  Australia.  In  No- 
vember 1910  the  Premier  of  Western  Aus- 
tralia stated  publicly  that  "  even  Kalgoorlie 
and  the  Golden  Mile  sink  into  insignificance 
when  one  listens  to  reports  regarding  the 
[Bullfinch]  property,  which  bids  fair  to  eclipse 
anything  discovered  in  the  history  of  the 
State."  No  punishment  can  be  greater  to  an 
irresponsible  official  than  to  quote  his  own 
fatuous  remarks.  The  episode  should  serve 
again  to  warn  the  public  against  opinions 
concerning  the  value  of  mines  expressed  by 


98 


THE    MINING    MAGAZINE 


persons  without  the  training  and  experience 
required  in  such  matters,  and  to  emphasize 
the  necessity  for  obtaining  proper  advice  be- 
fore subscribing  capital  for  hazardous  ven- 
tures. 


Impoverishment  in  Depth. 

The  paper  recently  submitted  by  Mr.  C.  O. 
Schmitt  to  the  two  technical  societies  in  Lon- 
don and  Johannesburg  appears  to  have  ex- 
cited much  attention.  We  have  refrained 
hitherto  from  augmenting  the  volume  of  dis- 
cussion because  the  main  point  at  issue  did 
not  seem  to  us  to  call  for  special  comment. 
However,  some  of  the  statements  provoked 
in  rebuttal  of  Mr.  Schmitt's  rather  confident 
assertions  cannot  be  passed  without  remark. 
Indeed,  we  congratulate  Mr.  Schmitt  on  hav- 
ing stimulated  investigation  of  a  problem  vital 
to  mining,  namely,  the  persistence  of  ore  in 
depth.  Next  to  the  submission  of  a  new  theory 
or  a  fresh  fact,  nothing  can  be  more  useful 
than  an  occasional  discharge  of  argument,  the 
electrical  effect  of  which  goes  far  toward 
clearing  the  intellectual  air  in  which  tech- 
nology lives.  The  gentleman  in  South  Africa 
assumed  that  the  yield  of  the  ore  broken  on 
the  Rand  had  decreased  in  its  content  of  gold 
as  the  depth  of  mining  had  increased.  This 
Ave  supposed  to  be  an  acknowledged  fact.  But 
Mr.  Schmitt,  not  content  with  assuming  a 
generalization,  proceeded  to  tabulate  the  yield 
of  the  mines  at  successive  horizons,  asserting 
that  the  average  yield  of  crude  ore  was  34s. 
per  ton  at  1000  ft.  and  would  diminish  to  17s. 
at  a  mile  below  the  present  surface.  For  each 
thousand  feet  he  predicated  a  definite  average 
yield,  and  with  it  a  regular  diminution  in  rich- 
ness. Not  satisfied  with  this  rash  venture, 
he  argued  backward  by  stating  that  as  the 
average  yield  per  ton  milled  was  now  28 
shillings,  therefore  the  average  depth  from 
which  the  ore  is  hoisted  must  be  2400  feet. 
Here  he  fell  foul  of  his  critics  and  left  him- 
self vulnerable  to  attack  from  several  direc- 


tions. As  is  well  known  the  depth  of  the 
mines  operated  at  Johannesburg  differs  widely, 
from  a  few  hundred  feet  in  the  outcrop  mines 
to  a  maximum  of  nearly  5000  feet  in  the  deep- 
est. Thus  the  Roodepoort  United  at  350  feet 
vertical  can  be  compared  with  the  Cinderella 
Consolidated  where  ore  is  being  stoped  at  4500 
feet.  The  ore  now  being  treated  comes  not 
only  from  mines  of  various  depth  but  comes 
from  different  levels  in  the  same  mines,  so 
that  nothing  but  detailed  and  precise  informa- 
tion concerning  the  source  of  the  ore  in  each 
mine  would  furnish  an  exact  basis  for  a  cate- 
gorical statement  concerning  the  average 
depth  at  which  the  ore  of  the  Rand  is  being 
stoped.  Such  information  is  not  available; 
it  was  not  available  to  Mr.  Schmitt,  nor  to  his 
critics.  Some  of  the  latter,  as  engineers  to 
controlling  '  houses,'  can  obtain  the  data  re- 
quired at  their  own  groups  of  mines,  but  they 
have  no  ready  access  to  the  records  of  the 
rival  houses.  We  note,  however,  that  Mr. 
H.  F.  Marriott,  consulting  engineer  to  the 
Rand  Mines  and  Central  Mining  group,  asserts 
"  on  the  most  complete  evidence  it  is  possible 
to  secure,"  namely,  "  that  of  the  assay-values 
of  samples  of  actual  reef- widths  taken  through- 
out all  the  mines,"  of  the  group  controlled  by 
his  house,  that  there  is  "  no  substantial  evi- 
dence today  ...  to  prove  a  general  deteriora- 
tion "  in  the  richness  of  the  ore.  This  assertion 
is  worth  a  lot  of  argument,  coming  from  such  an 
authority.  Mr.  Marriott  will  perform  a  service 
to  the  science  of  geology,  to  the  industry  of 
mining,  and  to  the  share  market,  if  he  will 
publish  the  evidence  required  to  substantiate 
what  he  has  said.  In  geology  we  have  reason 
to  believe  that  the  conditions  favouring  the 
solution  of  gold  are  increasingly  prevalent  as 
depth  is  gained,  while  on  the  contrary  the  con- 
ditions compelling  precipitation  are  predomi- 
nant in  the  immediate  approach  to  the  surface 
of  the  earth.  In  mining  we  have  the  irrefrag- 
able testimony  of  worldwide  experience  that 
man  has  never  yet  failed  to  go  deeper  than 


AUGUST,    1911 


99 


the  ore  rich  enough  for  him  to  exploit  and 
that  all  mines  become  eventually  exhausted 
in  depth.  In  the  share  market  the  idea  pre- 
vails that  these  generalizations  from  science 
and  experience  are  applicable  to  the  Rand, 
although  somewhat  modified  there  by  the  un- 
usual character  of  the  banket  deposit.  We  re- 
peat, therefore,  that  as  Mr.  Marriott  is  in  pos- 
session of  the  evidence,  he  can  perform  a  sig- 
nal service  and  further  enhance  his  reputation 
by  giving  a  complete  statement  of  the  case. 
At  the  very  time  when  he  was  controverting 
Mr.  Schmitt,  a  comprehensive  lecture  on  the 
gold-mining  industry  of  the  Rand  was  being 
delivered  by  Mr.  F.  H.  Hatch  before  the  In- 
stitution of  Civil  Engineers.  That  gentleman, 
an  acknowledged  authority  on  Rand  geology, 
stated  in  his  lecture  that  he  was  "  inclined  to 
the  view  that  a  gradual  impoverishment  with 
depth  does  exist.  It  would  be  quite  possible 
from  existing  records  and  assay-plans  to  settle 
this  really  vital  question." 

Our  own  view  of  the  matter,  which  may  be 
taken  as  that  of  many  others  who  lack  the  de- 
tailed information  accessible  to  consulting  en- 
gineers connected  with  groups  of  Rand  mines, 
but  who  have  a  general  knowledge  of  the  de- 
velopment of  the  Main  Reef  series,  and  a  wide 
acquaintance  with  the  history  of  gold  mining 
in  other  regions,  is  that  the  richest  ore  was  at 
the  outcrop  and  for  a  couple  of  hundred  feet 
down,  within  the  zone  of  secondary  enrich- 
ment due  to  vadose  waters.  Below  this  shal- 
low horizon  the  ore  showed  no  sudden  im- 
poverishment but  exhibited  variations  accord- 
ing to  structural  conditions,  as  affected  in  part 
by  dikes  and  other  intrusions  of  igneous  rock. 
As  depth  was  gained  an  occasional  area  of 
impoverishment  cut  into  the  stoping  ground 
of  this  or  that  mine,  while  in  rarer  cases  barren 
territory  was  succeeded  by  profitable  ground, 
so  that  the  evidence  did  not  all  point  one  way. 
With  additional  depth  the  areas  of  impoverish- 
ment began  to  eat  into  the  stoping  ground  to 
a  greater  degree,  compelling  some  mines  to 


close-down  and  others  to  consolidate  with  their 
more  fortunate  neighbours.  Broadly  speak- 
ing, we  believe — in  default  of  definite  proof  to 
the  contrary — that  the  amount  of  10  dwt.  ore 
is  less  at  2000  feet  than  at  1000  feet,  and  still 
less  at  3000  feet.  Of  course,  the  yield  of  the 
ore  in  the  mill  is  no  criterion.  In  the  early 
days  only  the  richest  stuff  was  worked  ;  as  the 
scope  of  operations  was  enlarged,  and  big 
mills  were  built,  the  poorer  ore  became  avail- 
able, for  the  working  cost  had  been  diminished. 
This  caused  a  rapid  increase  in  tonnage  and 
gross  output  of  gold,  with  a  compensating  de- 
crease in  the  yield  per  ton.  When  the  ten- 
dency to  lower  the  cost  without  regard  to 
ultimate  profit  had  been  carried  too  far,  a 
swing  in  an  opposite  direction  ensued,  and 
an  effort  was  made  to  increase  the  profit  by 
avoiding  ore  that  was  below  the  economic 
limit,  that  is,  by  refraining  from  the  vicious 
practice  of  augmenting  tonnage  and  getting  a 
fictitiously  low  cost  by  mixing  ore  below  grade 
with  that  which  was  well  above  grade.  Hence 
all  the  statistical  records  must  be  read  with  an 
eye  to  these  changes  of  policy.  Again,  it  is 
obvious  that  as  the  cost  diminished,  from  33 
shillings  per  ton  in  1895,  to  24s.  in  1905,  and 
to  17s.  in  1911,  the  ore  discarded  in  the  upper 
levels  of  the  deepening  mines  became  a  source 
of  profit  and  was  extracted,  together  with  that 
of  the  lower  workings.  Some  of  this  ore  in 
the  shallower  parts  of  a  mine  might  average 
poorer  than  that  taken  from  the  deeper  stopes 
and  yet  would  leave  a  good  margin  for  divi- 
dends. Moreover,  whereas  in  the  early  days 
.  only  the  South  Reef  and  Main  Reef  leader 
might  be  stoped,  the  bigger  Main  Reef  being 
unprofitable,  yet  as  the  mining  industry  be- 
came highly  organized  the  cost  of  working 
was  lowered  to  such  a  degree  that  the  Main 
Reef  became  a  source  of  profit,  and  is  now 
stoped.  These  are  among  the  causes  explain- 
ing the  difficulty  of  a  direct  comparison,  ex- 
cept by  those  in  a  position  to  dissect  the  re- 
cords.    That  the  Robinson  Deep  has  stoping 


100 


THE    MINING    MAGAZINE 


areas  fully  as  good  as  the  lower  workings  of 
the  shallower  Robinson,  Ferreira,  and  Wem- 
mer  mines  may  indeed  be  true  ;  and  the  Crown 
Deep  may  have  stretches  of  ground  better 
than  Its  neighbour  on  the  outcrop,  and  so 
forth ;  but  how  many  instances  to  the  con- 
trary could  be  cited  ?  We  forbear.  Is  it  not 
written  in  the  chronicles  of  liquidation,  con- 
solidation, and  re-construction  ?  A  mine  may 
sometimes  be  started  in  unprofitable  ore  but 
it  is  rarely  shut-down  when  in  profitable  ore. 
The  whole  problem  is  too  serious  for  rhodo- 
montade.  Mr.  Schmitt  may  have  erred  by 
proffering  generalizations  that  he  could  not 
prove,  but  his  most  effective  and  most  cour- 
teous critic  is  also  rash  when  he  talks  about 
the  "  comparatively  shallow  depth  of  5000 
feet."  How  many  mines  on  the  Rand  are 
going  to  be  worked  profitably  below  a  mile  in 
depth  ? 

Results  on  the  Rand. 

Any  analysis  of  the  results  achieved  during 
the  first  half  of  1911  by  the  mining  companies 
on  the  Rand  shows  one  salient  feature  :  a 
general  tendency  to  increase  the  operating  cost. 
This  is  due  in  part  to  the  inadequacy  of  the 
labour  supply  and  in  part  to  an  effort  to  restrict 
the  output  to  profitable  ore.  Four  of  the  seven 
mines  of  the  Gold  Fields  group  were  particu- 
larly handicapped  by  the  lack  of  labour,  that 
is,  the  quota  of  natives  required  for  the  con- 
tinually expanding  scheme  of  operations.  The 
Jupiter,  which  is  the  deepest  mine  of  this  group, 
has  an  increased  yield  of  4s.  per  ton,  but  the 
cost  rose  by  6s.  3d.,  so  that  the  profit  is  2s.  3d. 
less  than  in  the  corresponding  six  months  of 
1910.  Despite  the  general  increase  of  ton- 
nage the  aggregate  profitof  this  group  is  lower. 
The  Neumann  group  did  a  little  better,  especi- 
ally the  Wolhuter,  which,  with  a  larger  plant, 
has  produced  more  ore  at  a  slightly  smaller  ex- 
pense per  ton  ;  yet  three  out  of  the  five  mines 
under  this  control  exhibit  an  increased  cost. 
The  Goerz  group  with  four  companies  shows 


a  distinct  betterment  at  the  Lancaster  West 
and  Geduld  Proprietary.  The  two  big  Robin- 
son consolidations,  the  Langlaagte  Estate  and 
the  Randfontein  Central,  both  show  a  larger 
production,  with  a  diminished  profit  in  one  case 
and  a  notable  increase  in  the  other.  The  Albu 
group  suffered  from  re-organization  at  the 
Meyer  &  Charlton,  where  the  output  is  one  half 
what  it  was  for  the  same  period  last  year.  In- 
creased production  is  recorded  at  the  six  other 
mines  under  this  control,  with  a  bigger  aggre- 
gate profit  in  the  case  of  three  companies.  The 
Roodepoort  United  shows  notable  expansion, 
owing  to  additional  millingplant.  The  Barnato 
mines,  also  seven  in  number,  exhibit  gains  in 
every  instance  save  one,  the  Witwatersrand, 
in  which  the  grade  of  the  ore  has  fallen  with- 
out a  compensating  decrease  in  expenditure. 
The  two  Farrar  properties  have  had  bad  luck. 
At  the  East  Rand  Proprietary  two  serious  ac- 
cidents crippled  operations  for  a  time,  while  at 
the  New  Kleinfontein  the  cost  has  risen  in  ex- 
cess of  the  better  yield.  The  16  mines  con- 
trolled by  the  Rand  Mines  and  Central  Mining 
group,  formerly  identified  with  Wernher,  Beit 
&  Co.,  and  H.  Eckstein  &  Co.,  exhibit  an  in- 
crease of  aggregate  profits,  due  chiefly  to  the 
yield  of  the  City  Deep  and  Bantjes  mines. 
One  half,  that  is  8,  of  the  companies  under 
this  control  show  a  higher  profit  per  ton,  yet 
10  companies  show  a  bigger  rate  of  expense. 
Here  we  begin  to  see  the  result  of  the  new 
policy,  namely,  the  exclusion  of  ore  that  is  be- 
low the  economic  limit.  The  Village  Main 
Reef  is  the  leader  in  this  departure,  decreasing 
its  tonnage  in  the  six  months  from  253,000  to 
239,850,  increasing  the  total  expense  from 
;^413,651  to  ;^441,234,  and  making  a  profit  of 
^"23 1,979  mstead  of  ;^2 17,630.  The  average 
per  ton  for  yield,  cost,  and  profit  was  36s.  lOd., 
17s.  5d.,  and  19s.  5d.  respectively  for  this  half- 
year  as  compared  with  32s.  8d.,  15s.  6d.,  and 
17s.  2d.  for  the  corresponding  period  last  year. 
Apparentlynone  of  the  other  companies,  unless 
it  be  the  New  Modderfontein,  has  adopted  the 


AUGUST,    1911 


101 


new  policy  so  thoroughly  and  it  remains  to  be 
seen  whether  it  will  commend  itself  to  the  point 
of  imitation  by  the  other  groups.  It  is  pleas- 
ing to  note  that  the  big  consolidation  of  the 
Crown  Mines,  forming  the  most  productive 
gold  mining  property  in  the  world,  is  doing 
better  than  heretofore.  During  the  six  months 
the  output  of  gold  was  worth  £"1,358,796,  this 
being  the  yield  from  759,100  tons.  The  profit 
was  ^615,990.  Even  these  big  figures  are 
likely  to  be  augmented  by  the  starting  of  an  ad- 
ditional mill,  that  of  the  Crown  Reef,  whereby 
the  output  should  be  fully  30%  greater  than  it 
was  at  the  time  of  the  consolidation  two  years 
ago. 

The  Porcupine  Fire. 

To  those  who  read  newspaper  accounts  of 
catastrophic  events  the  reality  of  sorrow  and 
suffering  is  hardly  felt.  This  is  fortunate,  for 
the  whispering  wire  of  the  telegraph  transmits 
the  intelligence  of  disaster  so  easily  from  every 
quarter  of  the  globe  that  life  would  be  wrapped 
in  horror  if  our  sensitiveness  had  not  been 
dulled  by  iteration.  It  needs  therefore  a  per- 
sonal touch  to  awaken  sympathy  with  disaster 
in  a  distant  region.  Such  a  touch  we  regret 
to  say  was  not  wanting  in  the  case  of  the  con- 
flagration at  Porcupine,  for  among  the  lives  lost 
were  several  mining  men  known  to  us,  notably 
Leo  H.  Sulman,  a  young  engineer  of  much 
promise  and  the  worthy  son  of  a  distinguished 
father.  Indeed  the  forest  fires  that  raged 
among  the  mining  camps  of  Northern  Ontario 
in  the  middle  of  July  must  have  kindled  the 
keen  sympathy  of  many  who  read  this  Mag- 
azine. Most  of  those  engaged  in  mining  know 
something  about  such  devastating  occurrences, 
for  the  bush  fire  of  Australia,  the  burning  veld 
of  Africa,  and  the  forest  aflame  in  America 
have  often  taken  toll  of  men,  women,  and 
children,  not  to  mention  the  loss  in  livestock, 
machinery,  and  other  forms  of  property.  Ap- 
parently the  disaster  that  gave  a  lurid  fame 
to  the  gold  mines  of  Porcupine  was  like  other 


natural  visitations  of  this  kind.  A  wide  tract 
of  primeval  vegetation  dried  to  tinder  under  the 
cloudless  sky  of  an  inland  plateau  is  invaded 
by  prospectors  and  other  pioneers  in  search 
of  metallic  wealth.  An  abandoned  camp-fire, 
a  discarded  match,  or  the  hot  ash  of  a  sooth- 
ing pipe  suffice  to  ignite  the  dry  grass  and 
awaken  a  demon  of  destruction  amid  the 
resinous  pinewoods.  An  incendiary  origin  to 
such  occurrences  need  not  be  imputed  ;  it  has 
been  said  that  the  destruction  of  the  pegs  or 
other  monuments  that  mark  a  mining  claim 
may  be  desired  in  some  cases  involved  in 
litigation,  but  this  sinister  suggestion  may  be 
dismissed,  especially  in  Canada,  where  the 
system  of  surveying  is  so  simple  and  thorough 
as  to  facilitate  the  permanent  recording  of 
titles.  On  the  other  hand,  it  is  a  fact  that 
miners  are  not  sorry  to  see  the  ground  cleared 
by  fire,  because  this  tends  to  make  prospect- 
mg  easier.  In  the  Rocky  Mountains  it  is  be- 
lieved that  all  forest  fires  are  not  accidental, 
and  that  in  many  cases  they  have  been  al- 
lowed to  spread  by  men  who  could  have  ex- 
tinguished them  if  so  minded.  Northern  On- 
tario is  covered  with  a  mossy  undergrowth 
that  obscures  the  rock  surface,  and  the  new 
districts  in  which  gold  is  being  sought  were 
first  penetrated  with  difficulty  on  account  of 
thewidespread  forests  of  birchand  spruce.  To 
the  prospector  the  veil  that  Nature  throws 
over  her  treasures  is  only  a  hindrance  to  be 
removed,  laboriously  by  the  axe  or  rapidly  by 
the  flame.  Thus  the  fire  that  destroys  a  great 
natural  resource  is  to  him  not  an  unmitigated 
evil,  for  in  the  early  stages  of  mining  not 
much  timber  is  usually  required.  This  point 
of  view  does  not  involve  deliberate  incen- 
diarism, especially  where  human  habitations 
may  be  endangered,  but  it  does,  we  believe, 
explain  the  tardy  efforts  made  to  extinguish 
a  bush  fire  before  it  becomes  extensive.  In 
the  present  instance  several  local  fires  appear 
to  have  spread  until  a  whole  region  was  in  a 
state  of  conflagration.     It  will  be  remembered 


102 


THE    MINING   MAGAZINE 


that  in  June  the  Hollinger  and  other  neigh- 
bouring mines  suffered  from  this  cause  and  in 
the  early  part  of  July  the  Dome  Extension. 
For    many    weeks    a    succession  of  fires   in 
various  localities  had  become  a  feature  of  the 
long  summer  days.     The  culminating  disaster 
involved  a  stretch  of  country  nearly  250  miles 
long,  from  North  Bay  to  Cochrane,  stretching 
west  of  the  Temiskaming  &  Northern  On- 
tario railway,  which  connects  the   Canadian 
Pacific  and  Grand  Trunk   Pacific  lines.     A 
gale  fanned  the  flames  into  fierce  destructive- 
ness.     The  town  of  Cochrane  was  one  of  the 
first  to  be  destroyed  ;  then  followed  Elk  City, 
Miller  Lake,  Gowganda,  and  other  settlements 
brought  into  prominence  by  the  recent  devel- 
opment of  this  portion  of  Canada.     Finally, 
the  fire  reached  the  more  populous  locality  in 
the  vicinity  of  Porcupine  Lake,  where  a  min- 
ing boom   was  in   progress.     The  clouds  of 
smoke  had  been  seen,  but  the  warning  was 
unheeded  by  men  busily  at  work  and  grown 
familiar  with  bush-fires.     Soon,  however,  the 
burning  area  was  30  miles  long,  the  sun  was 
eclipsed  by  smoke,  and  the  swiftly  advancing 
flames  had  reached  the  township  of  Tisdale, 
attacking  the  Standard  and  Imperial  mines. 
The  danger  became  obvious  at  South  Porcu- 
pine.      Whistles   were  blown   by  the  mine- 
engines  and  everyone  prepared  for  flight.    The 
flames  continued  to  gain,  consuming  the  new 
buildings  and  plant  of  the  Dome  mine,  and 
then    the    Eldorado,    Preston  -  East    Dome, 
West   Dome,    and    North    Dome.      Finally 
the  town  itself  was  doomed  and  the  fire  swept 
around    the    lake,  destroying   several    settle- 
ments.    The  inhabitants  rushed  for  safety  to 
the  lake,  embarkmg  in  boats  of  every  descrip- 
tion.    Many  simply  stood  in  the  cold  water, 
some  of  them   succumbing  to  the  combined 
effect  of  heat  and  cold,  of  water  and  fire.    One 
of  the  worst  horrors  was  enacted  at  the  West 
Dome  mine,  where  Robert  Weiss,  the  super- 
intendent, not  realizing  the  true  position,  led 
his  men  into  the  timbered  shaft,  there  to  be 


suffocated.  Probably  100  lives  were  lost,  but 
an  exact  count  will  never  be  made,  for  among 
the  victims  are  included  many  small  parties 
of  prospectors  isolated  in  the  bush,  and  un- 
known, save  for  the  charred  bones  that  will 
be  found  in  years  to  come  when  the  tender 
green  of  a  new  growth  has  mantled  the  black 
trail  of  a  great  horror. 


Coast  Erosion. 

Those  who  spend  their  holidays  by  the  sea- 
shore in  the  long  summer  days  are  not  likely 
to  read  Blue-books,  more  especially  the  one  re- 
cently issued  by  the  Royal  Commission  "  ap- 
pointed to  inquire  into  and  to  report  on  certain 
questions  affecting  coast  erosion,"  but  even  the 
least  observant  among  them  will  not  fail  to  note 
the  traces  of  those  natural  changes  that  turn 
sea  into  dry  ground  and  the  habitable  land  in- 
to a  watery  waste.     On  the  coast  of  Kent  and 
Sussex,    and    generally    along   our    southern 
shores,  they  will  see  how  the  tides  are  eating 
into  our  tight  little  island,   undermining  the 
chalk  cliffs  and  whitening  the  waves  with  the 
spoil  of  the  land.     On  the  Suffolk  coast,  they 
will  hear  stories  of  forests  submerged  by  the  ad- 
vancing tide,  of  villages  over  which  the  white 
horses  now  race  joyously,  and  even  of  asunken 
church  from  which  in  days  of  calm  a  muffled 
bell  still  calls  to  prayer.     Such  stories  are  not 
all  fanciful.     On  the  coast  of  Yorkshire,  be- 
tween Flamborough  Head  and  Spurn  Point 
not  less  than  115  square  miles  of  land  has  been 
lost,  and  12  villages  are  known  to  have  been 
washed  away,  since  the  Roman  invasion.     At 
the  present  time  the  sea  is  encroaching  on  the 
coast  of  Holderness  at  the  rate  of  3  yards  per 
annum.     This   is  the  maximum  recorded  in 
England.     It  is  enough  to  provoke  intelligent 
curiosity. 

The  relative  position  of  ocean  and  land  is 
not  fixed,  because  the  surface  of  the  eaith  is 
undergoing  slow  oscillatory  movement  where- 
by the  sea  advances  in  some  localities  and  re- 
treats in  others.   Nature  knows  no  stagnation  ; 


AUGUST,    1911 


103 


life  is  synonymous  with  unrest ;  change  is 
everywhere  manifest ;  throughout  nature  the 
geologist  sees  "  the  traces  of  a  past  evolution 
and  the  germs  of  an  eventual  decay."  The 
south  and  east  coasts  of  England  exhibit  signs 
of  an  encroachment  by  the  sea,  due  to  a  re- 
latively slow  sinking  of  that  part  of  the  island. 
About  4000  years  ago  the  coast  of  Sussex  was 
fringed  by  a  belt  of  low  ground  extending  to 
what  is  now  the  10-fathom  line.  Behind  this 
coastal  plain  was  a  more  ancient  line  of  cliff 
obscured  by  grassy  slopes.  Since  then  the  rise 
of  the  sea-level  has  submerged  the  coastal  plain 
and  brought  the  higher  land  within  the  reach 
of  the  waves.  These  wash  the  chalk  and  loosen 
the  flint  pebbles  of  the  cliffs,  carrying  the  first 
out  to  sea  on  the  receding  tide  and  depositing 
the  second  as  beaches  of  shingle  and  dunes  of 
sand.  In  some  places,  as  at  Beachy  Head, 
the  wind  and  rain  help  to  intensify  the  erosion 
due  to  the  waves  of  the  Channel  and  long  be- 
fore the  water  laps  the  cliff  it  has  been  reduced 
to  a  condition  of  decay.  Yet  from  its  ruins  is 
made  a  defence.  The  shingle  and  sand  even- 
tually become  a  means  of  protection,  the  pre- 
vailing winds  and  currents  moving  them  until 
they  are  arrested  by  headlands  or  river-mouths, 
or  by  such  artificial  barriers  as  groynes  and 
piers.  There  they  accumulate  so  as  to  con- 
stitute an  effective  obstacle  to  the  further  at- 
tacks of  the  sea  and  in  many  cases  continue  to 
increase  in  area  so  as  to  form  alluvial  land  use- 
ful for  pasture,  delightful  forgolf,and  even  cap- 
able of  cultivation.  Thus  we  see  how  the  loss  of 
land  is  compensated.  The  Commission  ascer- 
tained that  within  a  period  of  35  years  "  about 
6630  acres  have  been  lost  to  the  United  King- 
dom, while  48,000  acres  have  been  gained." 
The  net  loss  is  small  but  it  is  impressive,  be- 
ing marked  by  an  occasional  landslip  or  the 
collapse  of  a  cliff  so  striking  as  to  seem  catas- 
trophic. On  the  other  hand  the  gain  is  scar- 
cely noticed,  for  it  exemplifies  those  geological 
forces  that  are  cumulatively  great.  The  result, 
however,  is  obvious,  for  example,  along  the 


west  coast  of  North  Wales,  where,  as  at  Har- 
lech and  Aberdovey,  a  sandy  foreshore  now 
stretches  between  Cardigan  Bay  and  the  for- 
mer line  of  slate  cliffs,  while  not  far  away  at 
Borth,  Barmouth,  and  Criccieth  the  encroach- 
ment of  the  sea  is  being  retarded  by  the  con- 
struction of  groynes  and  walls.  Balancing 
loss  and  gain,  the  Commission  concludes  that 

from  a  national  point  of  view  the  extent  of 
the  erosion  need  not  be  considered  alarming," 
By  the  construction  of  simple  defences,  by 
avoiding  dredging  below  the  low-water  mark, 
by  discrimination  in  the  removal  of  material  on 
the  sea  margin,  and  by  other  precautions,  even 
the  present  rate  of  loss  may  be  lessened. 

The  character  of  the  rock  composing  our 
island  bulwarks  is  an  important  factor  in  with- 
standing attack  from  the  sea.  On  our  southern 
and  eastern  shores  the  soft  deposits  of  chalk 
and  clay,  sandstone  and  limestone,  offer  but 
faint  resistance,  while  on  the  western  coasts 
of  Scotland,  Wales,  and  Cornwall  the  geologi- 
cally ancient  crystalline  rocks,  such  as  granite 
and  gneiss,  hard  slate  and  harder  diorite,  turn 
a  bold  front  to  the  invader.  Yet  even  there 
they  may  have  to  surrender  their  substance 
continually  to  the  onset  of  the  unwearied  sea* 
"  Water  would  wear  a  stone  "  says  a  homely 
proverb  ;  and  when  tons  of  water  are  hurled 
by  the  gale  against  the  Cornish  cliffs  even  they 
bow  before  the  compelling  force  of  old  Ocean 
and  yield  their  grudging  tribute.  Yet  out  of 
weakness  are  they  made  strong,  for  the  shat- 
tered rock  makes  a  barrier  and  the  broken 
stone  a  barricade  to  the  encroaching  tide,  de- 
laying, but  not  stopping  the  sure  advance.  To 
prevent  that  a  change  of  level  is  required, 
such  changes  as  are  observable  in  many  por- 
tions of  the  earth's  exterior  and  are  recorded 
in  the  rocks.  Raised  beaches  tell  the  tale  no 
less  than  the  marine  shells  buried  in  the  sedi- 
ment that  now  constitutes  the  mountain  peak. 
The  ancients  knew  something  of  this.  They 
loved  to  speak  of  the  Earth  as  a  sentient  be- 
ing, passing  through  changes  typified  in  their 


104 


THE    MINING    MAGAZINE 


own  lives.     Geology  has  but  heightened  the 
poetry  of  natural  evolution. 
"  There  rolls  the  deep  where  grew  the  tree. 
O  Earth,  what  changes  hast  thou  seen  ! 
There  where  the  long  street  roars, hath  been 
The  stillness  of  the  central  sea." 
Those  of  us,  and  there  are  many,  who  abate 
the  strenuous  effort  of  the  City  to  take  a  brief 
holiday  in  the  waning  summer  days,  traversing 
the  turf-clad  fore-shore  in  pursuit  of  the  "  wee 
bit  guttie  ball,"  may  remind  ourselves  as  we 
surmount  a  sand  dune  in  search  of  that  recal- 
citrant pillule  that 

Where  argosies  have  wooed  the  breeze, 

The  simple  sheep  are  feeding  now  ; 
And  near  and  far  across  the  bar 

The  ploughman  whistles  at  the  plough  ; 
Where  once  the  long  waves  washed  the  shore 
Larks  from  their  lowly  lodgings  soar." 


Bendlgo. 

The  report  lately  issued  by  the  Eagle- 
hawk  Consolidated  serves  to  remind  us  how 
little  British  capital  has  participated  in  the 
successful  mining  that  has  made  Bendigo 
famous,  for  Eaglehawk  is  adjacent  to  the  dis- 
trict formerly  known  as  Sandhurst  and  long 
celebrated  as  the  locality  where  the  deepest 
gold  mining  had  been  done.  Such  mines  as 
have  come  under  British  control  have  proved 
disappointing,  because  they  were  among  the 
least  productive  and  were  acquired  on  terms 
unlikely  to  give  satisfactory  results.  The 
mines  that  have  proved  so  remunerative  to 
local  owners  have  been  worked  on  a  system 
roughly  analogous  to  the  cost-book  system 
formerly  in  vogue  in  Cornwall.  When  the 
mine  was  in  rich  ore  the  profit  was  distributed 
in  dividends,  and  when  it  became  impoverished 
the  funds  for  further  development  were  raised 
by  calls.  When  the  owners  of  shares  were 
unable  to  contribute  fresh  working  capital  they 
sold  their  holdings,  if  a  purchaser  could  be 
found ;  if  not,  the  shares  became  delinquent. 
None  of  the  mines  started   with  any   large 


amount  of  working  capital  and  even  when 
they  happened  to  be  highly  productive  the 
directors  made  but  scanty  provision  for  a  rainy 
day.  Thus  large  blocks  of  shares  changed 
hands  with  the  vicissitudes  of  the  mine,  and 
a  few  local  capitalists,  like  George  Lansell,  a 
most  enterprising  mine-owner,  obtained  con- 
trol of  many  valuable  properties  merely  by 
paying  calls  on  shares  acquired  at  the  price 
of  a  few  pence  during  a  period  of  depression. 
No  mine  was  developed  so  as  to  have  any 
considerable  ore-reserve,  each  company  was 
conducted  on  a  hand-to-mouth  policy,  so  that 
none  of  the  mines  could  be  appraised  on  the 
basis  of  assured  resources.  Naturally  under 
these  conditions  a  British  promoter  found  little 
to  invite  his  financial  operations,  and  British 
engineers  found  conditions  quite  unfavourable 
to  any  of  the  conventional  methods  of  valua- 
tion. Each  mine  was  only  a  prospect  on  a 
large  scale  and  in  each  case  the  uncertainties 
were  out  of  proportion  to  the  actualities.  At 
one  time  a  scheme  was  hatched  with  a  view 
to  acquiring  all  of  George  Lansell's  holdings, 
but  the  death  of  that  veteran  prospector  and 
worthy  citizen  in  1906  put  an  end  to  the  idea. 
It  was  proposed  to  take  over  all  his  holdings, 
including  both  the  mines  that  had  fallen  on 
lean  times  as  well  as  those  then  making  fat 
dividends,  and  thus  to  ensure  a  fair  measure 
of  steady  productiveness.  But  even  this  pro- 
posal was  attended  with  many  difficulties,  it 
being  unlikely  that  any  London  administra- 
tion could  have  made  the  most  of  men  and 
methods  peculiar  to  the  district.  The  time 
may  come  when  a  large  system  of  exploration 
may  be  needed  to  resuscitate  some  of  the  ex- 
hausted mines  ;  then,  in  default  of  local  capi- 
tal, it  may  become  advantageous  for  the  owners 
to  offer  terms  on  which  English  speculators 
might  have  a  good  run  for  their  money  in  an 
attempt  to  discover  new  orebodies  among  those 
saddle-reefs  or  anticlinal  formations  of  quartz 
that  constitute  the  distinguishing  feature  of  old 
Bendigo. 


SPECIAL    CORRESPONDENCE 

News   from  our  own  Correspondents  at  the  principal  mining  centres 


JUNEAU. 

Southeastern  Alaska. —  Mining  opera- 
tions in  this  part  of  the  world,  while  now  at- 
tracting less  attention  than  formerly,  are  really 
being  conducted  with  unusual  success.  At  the 
same  time  the  foundations  are  being  laid  for 


The  big  open-cut  at  Treadwell. 


better  things  in  the  future.  As  usual  the  Alaska 
Treadwell  group  is  at  the  front.  Indeed  these 
great  mines  on  Douglas  island  form  the  largest 
single  enterprise  in  Alaska.  To  date  they  have 
produced  $43,568,000  and  it  is  interesting  to 
note  that  whereas  for  the  period  from  1890  the 
general  average  value  of  the  ore  has  only  been 
$2'40  per  ton,  85c. per  ton  has  been  paid  in  divi- 
dends ;  at  the  same  time  millions  have  been 
paid  from  income  for  plant,  development,  and 
2—3 


power  equipment.     The  story  of  these  mines 
has  been  often  told,  but  it  may  help  to  make 
clear  the  present  importance  of  the  enterprise 
to  state  that  900  stamps  crush  5000  tons  of  ore 
per  day  and  that  the  mines  are  1970ft.  deep. 
There  is  little  mining  as  yet  on  thelowestlevels 
since  it  is  the  policy  of  the  company  to  keep 
development  well  ahead  of  stoping  and  to  carry 
a  large  reserve  both  blocked  and  broken.  The 
latter  is  easily  done  since  the  stopes  are  worked 
on  the  shrinkage  system.     The  average  of  the 
ore  in reserveat  present  is  higher  than  the  aver- 
age that  has  been  worked  in  the  past,  owing 
especially  to  an  ore-shoot  on  the  1600  ft.  level 
of  the  Treadwell  mine  that  assays  unusually 
well.     Probably  the  total  reserve  of  the  avail- 
able ore  would  amount  to  7,000,000  tons  at  $3 
per  ton.     This  by  no  means  measures  the  life 
of  the  mine,  as  additional  ore  can  be  put  into  re- 
serve at  any  time  by  opening  additional  levels. 
Since,  however,  each  level  costs  approximately 
$300,000  and  six  years  elapses  from  the  time 
it  is  opened  to  the  time  when  it  is  abandoned, 
there  would  be  an  unnecessary  loss  through  in- 
terest charges  if  the  ground  were  opened  too 
long  in  advance.   The  mines  forming  the  group 
belong  to  three  companies,  the  x\laska  Tread- 
well, the   Alaska   Mexican,    and    the    Alaska 
United,  though  the  principal  owners  are  about 
equally  interested  in  all  and  the  management 
is  the  same.      Hoisting  and  milling  have,  how- 
ever, been  done  in  a  number  of  separate  plants 
and   there   has  been  relatively   little   centra- 
lization   so   far    as  actual   operation   is   con- 
cerned. 

Cyanide  Plant. — A  move  toward  such  a 
change  was  the  building  of  a  cyanidation  plant 
to  treat  the  concentrate  made  in  the  several 
mills.  A  part  of  this  plant  has  been  in  opera- 
tion since  February,  the  companies  continuing 
to  ship  concentrate  to  the  Tacoma  smelter  of 
the  American  Smelting  &  Refining  Co.,  to 
complete  an  old  contract.  The  new  plant  is 
actually  handling  at  the  present  about  SO  tons 
per  day  at  a  cost  of  $3  per  ton  and  with  a  sav- 
ing of  96?-^.  The  process  involves  fine  grind- 
ing in  tube-mills,  treatment  in  Dorr  classifiers, 
agitation  in  Pachuca  vats,  treatmentin  Kelly  fil- 
ter-presses, and  precipitation  in  Merrill  presses 
by  use  of  zinc-dust.  At  first  amalgamation  was 
used,  following  the  tube-mill  grinding,  ahead 
of  the  cyanidation,  but  this  was  found  to  be  un- 


105 


106 


THE    MINING    MAGAZINE 


necessary  and  expensive,  and  has  been  given 
up.  W.  P.  Lass,  the  cyanide  engineer,  and 
Robert  Kinzie,  the  general  manager  for  the 
company,  have  scored  a  notable  success  in  the 
building  and  successful  operation  of  this  plant. 
It  should  be  remembered  that  the  material 
treated  is  a  concentrate  made  on  vanners,  and 
assays  roughly:  gold  $42,  iron  40%,  sulphur 
40%,  silica  20%.  The  residue  is  being  saved. 
A  working  test  of  20  stamps  for  one  year 
is  being  started  to  determine  whether  it  is  com- 
mercially advisable  to  eliminate  amalgamation 
completely. 

Deep   Hoisting. — Another    move  toward 
centralization  is  the  preparation  for  hoisting 
from  both  the  Mexican  and  Treadwell  mines 
through  the  '  700  shaft '  of  the  Alaska  United. 
This  shaft,  which  is  centrally  located,  is  being 
re-timbered  and  equipped  for  handling  5000 
tons  per  day  from  a  derth  of  3000  ft.     The 
new  top  works  will  be  built  of  steel  and  con- 
crete to  avoid  the  ever-present  danger  of  fire 
where  wood  is  lavishly  used.     A  new  boiler- 
plant  is  being  built  to  furnish  steam   for  the 
Nordberg  hoist,   which  has  already   arrived. 
Despite  the  development  of  two  water-powers 
on  the  Island  and  one  across  Gastineau  Chan- 
nel on  Sheep  creek  the  companies  burn  as  much 
as  300  bbl.  oil  per  day,  even  in  summer  when 
the  most  water  is   available.      In  the  winter 
1000  bbl.  per  day  is  needed.     To  avoid  this  ex- 
pense the  development  of  the  power  of  Nigger 
creek,   on  the  mainland,   at   the   side  of   the 
Mendenhall  glacier,  has  been  undertaken.     A 
transmission  line  is  being  built  to  the  side  of 
the  power-house  and  with  current  sent  over  this 
Ime  the  new  works  will  be  erected  and  in  turn 
they  will  furnish  power  for  the  mine.     This 
will  make  it  possible  to  use  re-heated  air  from 
electric-driven   compressors    in    hoisting  and 
greatly  reduced  fuel  bills. 

Silver  Bow  Basin. — Back  of  Juneau,  in 
Silver  Bow  basin,  is  a  great  zone  of  ore,  essen- 
tially a  black  slate  within  which  are  ribbons  of 
white  quartz  containing  gold.  There  are  three 
important  mines  on  this  belt.  The  Alaska 
Perseverance,  farthest  to  the  south,  has  a  100- 
stamp  mill  and  is  preparing  to  erect  40  ad- 
ditional stamps  to  be  followed  by  tube-mills. 
At  the  other  end  is  the  Ebner  mine,  now  con- 
trolled by  the  Nevada-California  Copper  Co. 
This  concern  has  already  shipped  to  Juneau  a 
20-drill  compressor  and  a  200-stamp  mill,  but 
having  recently  lost  certain  water  rights,  the 
work  is  temporarily  checked.  Between  these 
two  mines  is  the  Alaska-Juneau,  which  was 
bought  some  years  ago  by  the  late  Capt.  Mein, 
and  in  which  Wernher,  Beit  &  Co.  have  had 


a  half-interest.  The  mines  have  been  under 
Alaska  -  Treadwell  management  and  recent 
changes  in  stock-holding  have  brought  the 
Alaska-Juneau  into  even  closer  affiliation  with 
the  Treadwell  mines.  The  Alaska-Juneau  is 
unique  as  a  low-grade  mine.  Roughly  ore 
worth  -SI '50  per  ton  has  been  mined  and  milled 
for  Sr09  in  a  40-stamp  mill  operating  three  to 
five  months  in  the  year.  Snow  and  lack  of 
water-power  have  prevented  a  longer  working 
season.  Indians  have  been  employed  almost 
exclusively  and  the  ore  has  been  won  by  '  glory- 
hole  '  mining.  F.  W.  Bradley  is  now  examin- 
ing the  property  to  determine  the  advisability 
of  enlarging  the  scale  of  operations. 

Berner's  Bay. —  In  this  vicinity  the  prin- 
cipal work  now  is  that  of  the  Kensington  Mines 
Co.,  in  which  W.  P.  Hammon  of  San  Fran- 
cisco has  become  interested.  The  old  proper- 
ties, which  have  been  in  litigation  for  some 
years,  have  been  consolidated  and  are  to  be  re- 
opened. Preparatory  work  is  now  being  done 
and  in  the  judgment  of  numerous  nnning  men 
there  is  an  opportunity  here  for  the  develop- 
ment of  another  group  of  low-grade  mines  of 
the  Treadwell  type.  The  Eagle  River  mine  is 
practically  idle  for  the  time  being ;  although 
$400,000  has  been  taken  from  the  pioperty, 
it  is  not  certain  that  the  vein  has  ever  been 
worked  where  the  rock  was  in  place.  Land- 
slides in  the  steeply  dipping  slate,  which  forms 
the  country  rock,  have  interfered  and  no  con- 
tinuous orebody  has  yet  been  found.  The 
Jualin,  a  smaller  property  containing  ore  that 
is  worth  $25  per  ton,  is  likewise  idle,  in  this 
case  owing  to  disagreement  among  owners. 

Other  localities. — At  Atlin,  in  British 
Columbia,  the  season  has  opened  and  J.  M. 
Ruffner  of  the  North  Columbia  Gold  Mming 
Co.  has  15  hydraulic  giants  at  work.  Farther 
south  near  Ketchikan,  mining  is  quieter.  The 
reported  deal  of  the  United  States  Smelting, 
etc.,  Co.  for  the  Mt.  Andrew  mine  failed  to  go 
through  owing  to  disagreement  as  to  price, 
though  the  examination  showed  a  good  body 
of  valuable  sulphide  ore  to  be  present.  The 
lb  and  the  Sulzer  mines  near-by  are  both  ship- 
ping regularly.  Farther  west  near  Sitka  the 
ChichagofT  mines  are  attracting  attention  ; 
though  not  so  large  as  the  Treadwell  they  are 
valuable  properties  yielding  rich  ore.  Brat- 
nober.  Rust,  and  Jarvis,  have  done  well  with 
the  De  Graff;  and  the  Golden  Gate,  owned 
by  \V.  P.  Mills,  is  reported  to  be  in  an  equally 
satisfactory  condition.  The  suicide  of  Captain 
D.  H.  Jarvis  was  particularly  deplored  here, 
at  Juneau,  where  he  was  so  well  known  and 
so  generally  liked. 


AUGUST,    1911 


107 


THE 


EAGLE    UIVElt    GLACIER,    AND   MINE,    ALASKA. 


108 


THE    MINING    MAGAZINE 


TORONTO. 

The  Porcupine  district  has  again  been 
visited  by  a  bush  fire,  which,  owing  to  the 
exceedingly  hot  and  dry  season  devastated  a 
large  area  and  was  with  difficulty  prevented 
from  extending  to  many  of  the  buildings. 
The  plant  of  the  Dome  Extension  was  de- 
stroyed causing  a  considerable  loss,  and  other 
properties  were  only  saved  by  strenuous  ex- 
ertions. The  lives  of  Capt.  Anchor  of  the 
Dome  Extension  and  a  number  of  men  were 
in  great  danger,  and  several  of  them  were 
severely  burned  in  fighting  the  flames.  These 
fires,  however,  are  regarded  by  others  than  the 
immediate  sufferers  as  blessings  in  disguise, 
as  the  clearing  away  of  the  forest  growth  ren- 
ders prospecting  and  the  tracing  of  rock  ex- 
posures much  easier.  The  known  gold-bear- 
ing area  of  the  district  has  latterly  been  con- 
siderably extended  by  new  finds, and  the  whole 
country  as  far  as  Sudbury  is  overrun  by  an 
army  of  prospectors.  A  great  rush  recently 
took  place  to  Bristol  township  where  a  note- 
worthy discovery  was  made  by  John  Bridge, 
a  former  Cobalt  miner,  at  a  point  about  ten 
miles  southwest  of  the  Hollinger  mine  and 
near  the  Mattagami  river.  A  well  defined 
vein  about  200  ft.  wide  with  good  gold  show- 
ings was  found  on  one  of  two  rock  exposures. 
The  remainder  of  the  neighbourhood  is  all 
under  swamp  but  has  nevertheless  been  staked 
in  all  directions  in  the  hope  that  something  of 
value  m^ay  be  found. 

At  the  Rea  the  main  shaft  is  down  240  ft. 
and  will  be  sunk  to  the  500  ft.  level,  with  de- 
velopment carried  on  at  the  intervening  levels, 
drifts  being  run  to  tap  the  orebody  in  the  main 
lode.  A  second  sJiaft  is  being  put  down,  to  be 
connected  with  shaft  No.  1  at  the  first  level. 
A  rather  spectacular  find  has  been  made  on  a 
property  owned  by  the  Armstrong- Booth  syn- 
dicate just  south  of  the  Rea.  Free  gold  has 
been  panned  in  considerable  quantities  from 
the  loose  dirt  beside  numerous  stringers.  The 
Preston  East  Dome  is  opening  up  a  15  ft.  vein 
on  one  of  its  properties  adjoining  the  Dome. 
The  Bewick  -  Moreing  syndicate  has  estab- 
lished two  more  camps,  known  as  No.  3  and 
No.  4.  The  former  is  situated  on  the  proper- 
ties adjoining  the  Dome  Extension  to  the  north 
and  east,  and  the  other  on  the  Timmins  group 
in  Deloro  township.  The  men  are  at  present 
engaged  in  stripping.  The  Porcupine  Inves- 
tors, a  company  organized  in  London  with  a 
capital  of  ;^1,500,000,  has  purchased  three 
claims  lying  north  of  the  Dome  and  North 
Dome,  and  has  let  contracts  for  drilling  pre- 
paratory to  undertaking  development.     The 


Porcupine  Canada  Gold  Mines,  another  new 
company  representing  German  and  British 
capital  promoted  by  Baron  G.  von  Polenz, 
has  several  Porcupine  claims  under  option  ; 
these  are  being  investigated  by  engineers.  The 
Imperial  has  sunk  to  the  100-ft.  level  and  re- 
cently struck  a  good  vein  6  to  8  ft.  wide.  The 
Foley-O'Brien  has  discovered  a  vein  in  a  drift 
at  the  160-ft.  level,  intersected  with  rich  strin- 
gers showing  free  gold.  The  Achilles,  a  Mont- 
real company,  has  a  good  showing  in  a  7  ft. 
vein  found  at  the  125-ft.  level  on  its  property 
to  the  north  of  Porcupine  lake.  The  Porcu- 
pine branch  of  the  Temiskaming  &  Northern 
Ontario  railway  is  now  open  for  traffic  and 
large  quantities  of  freight  are  going  forward. 

Cobalt.  —  Comparatively  little  interest  is 
being  taken  in  Cobalt  and  not  much  news 
comes  from  that  quarter.  A  new  vein  of  high- 
grade  ore  has  been  cut  by  the  Nipissing  in  a 
cross-cut  from  shaft  No.  123  at  the  100-ft. 
level,  near  the  O'Brien  line.  The  find  is  re- 
garded as  significant,  being  the  first  practical 
result  of  development  in  the  Keewatin  forma- 
tion in  that  part  of  the  property.  No.  12  shaft 
has  been  pumped  out  and  good  ore  is  being  ex- 
tracted. The  La  Rose  continues  to  improve 
its  position.  The  total  output  for  the  five 
months  ending  May  31  was  l,522,580oz.  silver 
of  a  gross  valuation  of  §802,677.  The  profits 
amounted  to  $535,132.  At  this  rate  the  mine 
is  earning  more  than  double  its  dividend  re- 
quirements. It  has  a  present  cash  surplus  of 
$1,300,000.  The  Nova  Scotia  is  getting  good 
milling  ore  from  a  shoot  40  ft.  long  and  4  ft. 
wide  on  the  150-ft.  level.  A  10-stamp  mill 
has  been  ordered  by  the  Wettlaufer  in  the 
South  Lorrain  area,  where  transportation  diffi- 
culties prevent  the  shipment  of  low-grade  ore 
at  a  profit.  The  capital  of  the  Trethewey  has 
been  increased  from  $1,000,000  to  $2,000,000. 

Coal  Mining. — A  recurrence  of  the  land- 
slide catastrophe  of  1903  at  Frank,  in  Alberta, 
where  a  number  of  lives  were  lost,  is  seriously 
threatened.  R.  W.  Brock,  the  Director  of  the 
Canadian  Geological  Survey,  reports  that 
cracks  have  appeared  in  the  rocks  on  the 
northwest  shoulder  of  Turtle  Mountain  over- 
looking the  town,  and  that  any  further  work 
on  the  coal  seams  below  may  precipitate  a  dis- 
aster without  warning.  The  mountain  has 
been  inspected  by  the  Survey  since  the  former 
landslide,  and  it  has  been  noticed  of  late  that 
the  fissures  have  widened.  The  mine  is  oper- 
ated by  the  Crow's  Nest  Pass  Coal  Company. 

The  colliery  at  Port  Hood,  Nova  Scotia, 
owned  by  the  Port  Hood  &  Richmond  Rail- 
way &  Coal  Co.,  has  been  flooded  from  the 


AUGUST,    1911 


109 


Atlantic  and  is  to  be  abandoned,  reclamation 
being  considered  impossible.  The  Dominion 
Steel  Corporation  is  operating  a  new  colliery 
at  Birch  Cove  and  has  started  the  construc- 
tion of  a  railway  about  four  miles  long  to  con- 
nect the  colliery  with  Morien  Junction.  When 
transport  is  obtained  a  new  slope  will  be  sunk 
and  mining  actively  resumed.  It  is  expected 
that  shipments  will  be  made  before  the  close 
of  navigation. 

James  Douglas,  of  New  York,  has  made  a 
donation  of  $50,000  to  Queen's  University, 
Kingston,  as  he  some  time  ago  promised  to 
do,  on  condition  of  its  being  freed  from  de- 
nominational control. 

SAN  FRANCISCO. 

Alaska. —  Interest  on  the  Pacific  Coast  now 
chiefly  centres  in  the  Alaskan  coal  lands  and 
the  California  smelters.  The  Cunningham 
group  of  claims  were  finally  rejected,  thus 
vindicating  Gifford  Pinchot  and  his  subordin- 
ates,and  discrediting  Ballinger.  As  the  matter 
now  stands,  not  only  the  sequestration  of  these 
valuable  coal  lands  has  been  prevented,  but  it 
has  been  established  that  there  is  at  present 
no  practicable  legal  method  of  developing  the 
coal  resources  of  Alaska.  As  a  result  feeling 
runs  high  here,  although  the  seriousness  of  the 
situation  has  been  greatly  magnified,  in  the 
interest  of  the  corporations  engaged  in  exploit- 
ing Alaska.  In  spite  of  the  evident  demand 
for  constructive  legislation  that  will  permit  the 
development  of  the  coal  mining  industry  in 
this  area,  there  is  no  possibility  of  any  being 
enacted  at  this  special  session  of  Congress,  as 
the  Democratic  majority  in  the  House  is  deter- 
mined to  allow  nothing  to  divert  attention  from 
Canadian  reciprocity  and  the  wool  schedule. 
A  lively  scandal  has  developed  over  the  har- 
bour of  Controller  bay,  one  of  the  two  outlets 
for  the  Alaskan  coalfields.  One  R.  S.  Ryan 
came  to  Washington  at  the  time  the  Chugach 
National  Forest  was  created,  and  persuaded 
the  authorities  to  exclude  the  shores  of  Con- 
troller bay  from  the  Forest.  Then  he  and  his 
associates  filed  upon  it,  obtaining  control  of 
the  harbour.  Now  it  appears  that  Ryan  was 
acting  in  behalf  of  the  Guggenheims,  and  that 
when  he  saw  President  Taft,  who  asked  him 
whom  he  represented,  he  claimed  to  be  acting 
independently.  President  Taft  was  not  satis- 
fied with  this,  and  finally  Chas.  P.  Taft  was 
induced  to  call  on  the  President  and  influence 
him  to  accede  to  Ryan's  request.  The  matter 
has  been  greatly  exaggerated  by  an  irrespon- 
sible Press,  but  the  present  administration  will 
certainly  derive  little  credit  from  it.     The  ap- 


pointment of  W.  L.  Fisher  as  Secretary  of  the 
Interior  was  hailed  as  a  victory  by  the  forces 
that  have  opposed  the  monopolization  of  Al- 
askan coal  resources,  and  it  is  not  unlikely  that 
they  will  in  the  end  prevail.  Meanwhile  the 
Guggenheim  syndicate  controls  Cordova  and 
Controller  bay,  the  only  outlets  from  the  coal- 
fields. 

Smelter  fume.  On  June  20  the  case  of 
the  Shasta  county  farmers  against  the  Balak- 
lala  smelter  was  heard  in  the  United  States 


Outcrop  of  the  HoUinger  lode  on  the  MiUer-Middlcton  claims. 

Circuit  Court  of  San  Francisco  and  Judge 
Morrow  affirmed  the  injunction  closing  the 
smelter.  The  smelting  company  was  allowed 
35  days  more  of  operation,  so  that  it  might  use 
up  the  stock  of  ore  and  coke  already  on  hand. 
This  is  an  unmerited  blow  to  the  Cottrell  pro- 
cess,which  had  been  employed  at  this  plant  for 
removing  the  solid  particles  from  the  fume. 
A.  H.  Trotter,  superintendent  of  the  smelter, 
has  recently  given  out  a  statement  saying  : 
"  The  experiments  on  unit  5  of  the  Cottrell 
plant  have  been  a  complete  success,  and  have 
fully    demonstrated   the   adaptability  of   the 


110 


THE    MINING    MAGAZINE 


Cottrell  system  for  the  elimination  of  solids 
and  SO3  from  our  gases.  At  the  present  time 
it  is  effecting  a  very  satisfactory  clearance  of 
the  solid  particles,  and  it  can  be  made  to  do 
better  work  at  comparatively  small  expense. 
The  Cottrell  system  will  do  all  that  has  been 
expected  from  it  and  I  wish  to  be  distinctly 
understood  that  I  have  never  stated  that  it  has 
been  a  failure  or  a  loss  to  this  company.  I 
beUeve  that  the  management  of  this  company 
is  well  satisfied  with  the  operation  of  the  Cot- 
trell plant." 

The  Cottrell  process  has  also  been  success- 
fully applied  to  the  removal  of  water  from 
crude  petroleum,  the  rights  to  the  process  for 
this  use  having  recently  changed  hands  at  a 
high  figure.  The  Balaklala  is  a  well  developed 
mine,  with  an  ore  reserve  of  about  2,000,000 
tons,  averaging  2'65%  copper,  together  with 
gold  and  silver.  The  situation  of  the  share- 
holders is  a  serious  one,  as  the  present  selling 
price  of  the  shares  represents  a  loss  of  $6  to 
$8  per  share. 

Oil.  The  large  demand  for  kerosene  and 
gasoline  for  the  Oriental  trade  has  greatly  in- 
creased the  im.portance  of  the  Pacific  Coast  oil 
industry.  Rumours  have  been  industriously 
circulated  concerning  the  advent  of  the  Shell 
interests  into  this  field,  the  latest  being  that 
the  latter  are  about  to  construct  a  refinery  at 
Martinez,  California.  It  is  also  reported  that 
the  Standard  Oil  is  about  to  construct  a  mil- 
lion dollar  distributing  plant  at  Richmond 
Beach, on  the  shores  of  Puget  Sound,  and  that 
the  Shell  syndicate  will  also  erect  a  competing 
station.  Reports  from  the  Katalla  oilfield, of 
Alaska,  are  to  the  effect  that  five  wells  are 
already  producing  and  several  drilling  rigs  are 
ready  to  start.  A  pipe  has  been  laid  from  the 
old  English  property  to  the  storage  tanks.  At 
Katalla  a  small  refinery  has  been  erected  to 
furnish  gasoline  for  local  consumption. 

Copper. — The  campaign  against  the  Utah 
Copper  Co.  seemed  to  produce  but  little  in  the 
way  of  results.  Recently  the  ferocity  of  the 
attack  on  this  company  has  increased,  but  the 
market  has  refused  to  be  impressed  thereby. 
Early  in  July  the  Miiiitig  and  Scientific  Press, 
in  a  long  editorial,  drew  attention  to  the  good 
work  done  by  the  company's  engineers  and  the 
injustice  and  unreasonableness  of  the  attack 
made  upon  them.  The  monthly  report  of  the 
Copper  Producers  Association  for  June  was 
favourable,  the  production  having  decreased 
2,000,000  lb.,  as  compared  with  May,  while 
stocks  on  hand  decreased  8,500,000  lb.  As 
European  purchasers  are  expected  to  take 
large  amounts  during  July  it  is  not  improbable 


that  1  further  decrease  will  result  during  the 
month.  The  market  is  now  firm  with  electro- 
lytic quoted  at  New  York  at  12"48c.  Just  be- 
fore leaving  for  Europe,  Daniel  Guggenheim 
gave  out  an  interview  in  which  he  expressed 
the  opinion  that  a  '  runaway  '  might  be  ex- 
pected from  the  present  decrease  of  stocks  and 
production.  A  howl  of  derision  has  gone  up, 
and  the  general  opinion  is  that  Mr.  Guggen- 
heim's imagination  has  run  away  with  hun. 

Recent  reports  from  the  Chino  and  Ray 
properties  are  to  the  effect  that  6,000,000  tons 
of  ore  averaging  2%  copper  has  been  added  to 
the  Chino  reserve,  giving  a  total  of  50,000,000 
tons.  The  power-plant  is  nearly  finished  and 
the  first  section  of  the  mill  is  expected  to  start 
in  September.  The  mine-work  is  well  in  hand 
and  the  management  will  soon  be  able  to  pro- 
duce 5000  to  6000  tons  of  ore  daily  by  steam- 
shovels.  In  the  Ray  over  two  miles  of  under- 
ground work  has  been  done  m  the  past  year, 
and  the  system  of  stoping  employed  has  been 
entirely  satisfactory.  Three  sections  of  the 
mill  are  now  in  operation,  treating  1100  to 
1200  tons  per  day  each.  Oil  is  being  substi- 
tuted for  coal,  as  fuel,  in  the  power  and  smel- 
ting plants. 

JOHANNESBURG. 

Standardization  on  the  Rand  is  con- 
spicuous by  its  absence,  from  the  policy  ad- 
opted by  the  directors  of  the  various  groups 
down  to  the  method  of  placing  a  piece  of  tim- 
ber underground.  For  instance,  about  a  year 
ago,  a  deal  of  excitement  was  caused  by  the 
'  square  fathom  '  scheme,  evolved  ostensibly 
by  the  consulting  engineer  of  one  of  the  lar- 
gest groups.  The  new  policy  was  to  revolu- 
tionize things  on  the  Rand.  Low  costs  did 
not  matter,  profit  was  the  aim,  combined  with 
narrow  stope-widths  and  close  sorting.  In 
other  words  the  eyes  were  to  be  picked  out 
of  the  mines.  Yet  now  that  a  year  has  passed 
a  director  of  the  group  that  inaugurated  the 
'  square  fathom  '  scheme,  when  speaking  at 
the  general  meeting  of  another  large  group, 
says  that  the  ideal  method  of  working  is  to 
take  everything  as  it  comes  and  work  the 
mines  so  as  to  yield  an  average  grade  and 
prolong  the  life  of  the  mine  as  long  as  pos- 
sible. This  variation  of  policy  may  be  all 
right  from  the  share-market  standpoint,  but  it 
certainly  does  not  tend  to  improve  the  actual 
working  of  the  mines,  since  each  variation  of 
policy  is  apt  to  cause  a  change  in  the  per- 
sonnel of  the  staff,  followed  by  an  unsettled 
feeling,  extra  expenditure,  and  waste  of  time. 
So  much  for  a  change  in  policy.     The  same 


AUGUST,    1911 


111 


applies,  only  in  smaller  degree,  throughout  the 
detailed  working  of  each  mine.  For  example, 
in  underground  work,  it  may  be  proposed  to 
run  four  large  machines  1000  ft.  from  the  main 
air-column.  One  man  thinks  a  1|  in.  pipe 
will  be  sufficient  to  supply  all  the  air  required  ; 
Ih  in.  pipe  is  therefore  used.  Everything  is 
ready  and  it  is  found  that  only  3  machines 
can  be  run  off  the  li  in.  pipe  with  the  pres- 
sure available.  Another  man  might  advocate 
2  in.  or  even  3  in.  piping.  Of  course  the  size 
of  pipe  required  can  be  worked  out  by  for- 
mula, yet  in  cases  of  this  kind  it  would  be 
much  handier  if  certain  standards  were  estab- 


sary  to  revert  partly  to  steam.  The  new 
manageris  James  Morris,  late  of  the  East  Rand 
Proprietary,  and  the  new  mechanical  engineer 
is  H.  L.  Templar,  late  of  the  Ferreira. 

Ferreira. — The  accompanying  photograph 
illustrates  the  open-cut  operations  still  pro- 
ceeding, right  in  the  town  of  Johannesburg, 
although  the  mine  was  started  in  1888.  The 
open-cut  work  chiefly  consists  of  taking  out 
the  surface  pillar,  about  40  ft.  wide,  by  under- 
hand stoping  from  the  surface.  The  trucks 
are  either  run  on  old  filling  or  on  stulls  below 
the  pillar ;  when  filled  they  are  slung  by 
means  of  chains  from  the  rope  shown  in  the 


WORKING  IN   THE   OPEN-CUT  AT   THE  FERREIRA. 


lished,  if  only  by  one  group,  in  order  to  in- 
crease efficiency  and  save  money. 

City  Deep. — At  the  moment  of  writing 
the  price  of  City  Deep  shares  is  falling  rapidly 
and  they  now  stand  at  about  65s.  This  can 
only  be  due  to  the  fact  that  with  the  change 
in  management,  together  with  the  change  of 
resident  mechanical  engineers,  it  has  been 
discovered  that  the  magnificent  new  plant  has 
serious  defects  that  require  remedying  before 
it  can  run  smoothly.  The  mill  will  require 
several  expensive  alterations.  The  hoisting 
engines,  in  so  far  as  the  ropes  are  concerned, 
are  giving  trouble.  There  is  a  shortage  in 
electric  power,  so  that  it  has  become  neces- 


photograph  and  hoisted  bodily  by  an  old  steam 
navvy.  As  the  ground  is  stoped  out  it  is 
filled  again  with  waste  from  the  dump. 

Dust  and  Phthisis.  —  Experiments  are 
still  being  made  with  various  methods  for 
overcoming  the  dust  trouble.  The  success  of 
hammer-drills  and  the  fact  that  they  require 
only  one  boy  to  manipulate  them,  and  also 
their  suitability  in  back-stoping  the  ground 
left  in  the  older  mines,  has  tended  greatly  to 
increase  the  number  of  dry  holes.  This  being 
the  case  it  is  imperative,  not  only  to  minimize 
the  dust  but  also  the  operating  cost,  that  some 
method  be  adopted  by  means  of  which  all 
dust  is  eliminated  and  the  drilling  itself  facili- 


112 


THE    MINING    MAGAZINE 


tated.  The  latest  idea  is  the  one  under  trial 
at  the  Nourse  mines,  where  pipes  conveying 
water  under  pressure  are  laid  down  through- 
out the  mine,  so  that  water  can  be  injected 
alongside  the  drill  while  the  machine  is  run- 
ning. This  kills  the  dust  and  also  favourably 
affects  the  drilling. 

Machine  -  Drill  Sloping.  —  Interesting 
figures  are  to  hand  showing  the  results  of 
stoping  with  small  reciprocating  machine- 
drills  as  compared  with  large  machines  and 
hammer-boys  at  the  Robinson  Deep  mine. 
The  comparative  figures  are  as  follows : 


Cost  per 
fathom 
s.     d. 

By  hand... 80    47 

By    small   machines    75    7'2 
By  large  machines...     72    S'8 


Work  done 
Stope-width         per  shift 

Inches      Fathoms         Tons 


5ri 
547 
59'9 


0.076 
0'55 
063 


0"915 
6'432 
8'410 


From  the  above  figures  it  appears  that  the 
cost  of  hand  labour  is  above  the  average ; 
0'076  fm.  per  boy-shift  is  bad.  This  figure 
should  be  about  O'l  fm.  in  good  ground  and 
with  good  hand-stopes.  The  small  machines 
do  comparatively  well  and  the  ground  must 
be  easy  to  obtain  these  results.  From  a  la- 
bour point  of  view  a  small  machine  requires 
the  same  number  of  boys  as  a  large  machine, 
and  except  in  stopes  where  the  hanging  is 
bad  and  a  large  machine  would  shake  the 
ground  too  much,  they  will  not  bear  com- 
parison with  large  machines,  even  when  it  is 
required  to  keep  the  stope-width  as  low  as 
possible.  The  figure  0'63  fm.  per  large  ma- 
chine is  also  much  below  the  average  for  a 
stoping-width  of  about  3  ft. ;  this  figure  should 
at  least  be  in  the  neighbourhood  of  0'75  fm. 
per  machine  per  shift.  In  March  1911,44'55% 
of  the  ground  broken  at  this  mine  was  done 
by  small  machines,  3r84/o  by  hand,  and 
23*61%  by  large  machines. 

The  Butters  Filter. — An  official  report  is 
just  out  dealing  with  the  results  obtained  from 
the  trial  of  the  Butters  filter  at  the  Crown 
Mines.  The  broad  result  is  that  the  Butters 
plant  has  been  taken  over  as  a  permanent  fea- 
ture of  the  Crown  Mines  equipment  and  is  also 
to  be  enlarged  to  a  capacity  of  1200  tons  per 
day.  The  report  gives  the  following  interesting 
information  : 

(l)  The  true  average  of  Adair-Usher  resi- 
due was  shown  to  be  0'423  dwt.,  whereas  the 
average  of  tank  samples,  taken  in  the  usual 
way,  gave  0*225  dwt.  per  ton.  (2)  The  Butters 
filter  made  a  total  recovery  of  0*333  dwt.  per 
ton  from  Adair-Usher  residue  averaging  0*423 
dwt.  To  quote  the  report :  "  The  conclusion 
reached  from  this  six  months  trial  may  be 
stated  as  follows:  (l)  Owing  to  the  fact  that 


in  the  past  Adair-Usher  residues  have  been 
considerably  under- estimated,  as  confirmed  by 
recent  investigation,  the  filter  may  reasonably 
be  expected  to  show  a  net  saving  over  the 
Adair-Usher  process  of  from  0*20  to  0*5  dwt. 
per  ton  of  slime  filtered.  (2)  Under  normal 
conditions  the  filter  may  reasonably  be  expected 
to  show  a  gross  savingover  the  decantation  pro- 
cess of  about  0*20  dwt.  per  ton,  or  a  net  saving 
of  about  0*12  dwt.  per  ton,  of  slime  filtered. 
(3)  As  regards  cost  of  treatment  this  has  been 
given  at  9d.  per  ton  during  the  earlier  stages 
of  the  trial." 

MEXICO. 

Pearson  Oil  Interests. — Rumours  of  the 
contemplated  sale  of  the  Pearson  holdings  in 
Mexico  to  the  Texas  Oil  Co.,  headed  by  John 
W.  Gates,  are  persistent,  notwithstanding  a 
recent  denial  by  Lord  Cowdray.  Following 
the  recent  examination  of  Pearson  holdings 
by  officials  of  the  Texas  Oil  Co.  and  the  Gulf 
Refining  Co.,  Pearson  officials  in  Mexico  City 
admitted  that  the  purchase  of  Pearson  crude 
oil  for  shipment  to  the  United  States  was  con- 
templated, and  that  the  holdings  might  pass 
to  American  interests  in  the  event  of  an 
agreement  on  price.  It  has  been  reported 
that  the  present  government  of  Mexico  would 
object  to  the  transfer  of  the  Pearson  conces- 
sions as  they  now  stand,  but  this  report  lacks 
confirmation.  Finance  Minister  Ernesto 
Madero,  uncle  of  Francisco  I.  Madero,  the 
revolutionist  leader,  stated  recently  in  an  in- 
terview that  the  provisional  government  was 
not  conducting  an  investigation  into  the  affairs 
of  any  corporation,  and  that  all  rights  held 
legally  by  corporations  would  be  respected. 
When  the  American  oil-men  recently  visited 
the  Potrero  field  in  the  State  of  Veracruz 
they  were  given  a  view  of  the  great  Pearson 
gusher  in  action.  It  required  the  efforts  of 
three  men  to  open  the  gate-valve  holding  the 
Potrero  monster,  and  the  gusher  was  allowed 
to  perform  for  20  minutes.  Oil  was  thrown 
to  a  height  of  491  feet,  and  the  flow  was  esti- 
mated at  100,000  bbl.  daily.  In  the  earthen 
reservoir  into  which  the  flow  of  the  well  was 
finally  turned  after  it  had  flooded  the  surround- 
ing country,  the  Pearsons  have  3,000,000  bar- 
rels of  oil.  It  is  a  mile  around  the  reservoir,  and 
at  places  the  oil  is  30  ft.  deep.  The  capping 
of  the  gusher  was  an  herculean  task,  and  much 
time  was  consumed  in  accomplishing  it.  The 
Pearsons  have  two  stretches  of  6-in.  pipe-line 
between  Potrero  and  the  Gulf  port  of  Tampico, 
one  extending  from  the  field  to  the  Tamiahua 
lagoon,    and    the    other    from    the  lagoon   to 


AUGUST,    1911 


113 


Tampico.  Barges  carry  the  oil  for  some  dis- 
tance on  the  lagoon.  The  pipe-line  will  be 
made  continuous  by  the  building  of  another 
link,  and  an  8-in.  pipe-line  will  be  built  from 
the  oilfield  to  the  Gulf  port  of  Tuxpan.  Be- 
sides the  big  gusher,  the  Pearsons  have  five 
wells  in  the  Potrero  field,  two  of  them  inter- 
mittent gushers. 

Other  Oil  Interests. — The  first  shipment 
of  Mexican  crude  oil  to  the  United  States 
was  made  recently   by  the  Huasteca    Petro- 


The  Potrero  Gusher. 

leum  Co.,  a  subsidiary  of  the  Mexican  Petro- 
leum Co.,  Ltd.,  of  which  E.  L.  Doheny  is 
the  head.  The  shipment  amounted  to  32,000 
bbl.,  and  was  carried  by  a  Standard  Oil  Co. 
steamer  from  Tampico  to  Sabine  Pass,  Texas. 
It  is  reported  that  the  Huasteca  Co.  has  en- 
tered into  a  contract  to  supply  fuel-oil  for  the 
Southern  Pacific  locomotives  in  service  in 
Texas,  and  that  8000  bbl.  daily  will  be  re- 
quired. The  Mexican  oilfields  now  are  at- 
tracting more  attention  than  ever,  and  much 
exploration  and  development  is  in  progress. 

Ocampo. — The  future  of  this  mining  re- 
gion, including  Conchefio,   Pinos  Altos,  and 


Candamena,  depends  mainly  on  the  supply  of 
motive  power.  The  country  has  been  mined 
for  so  many  years  that  all  the  cheap  wood  has 
been  cut,  the  cost  now  being  from  |4  to  .$7 
per  cord  at  the  various  camps.  There  is  a  pro- 
ject to  erect  a  plant  at  the  Basaseachic  falls, 
owned  by  the  Sierra  Mining  Co.  These  falls 
have  a  vertical  drop  of  980  ft.  and  with  suit- 
able storage  arrangements  3000  hp.  may  be 
developed  there.  The  same  company  is  now 
building  a  300  hp.  wood-steam-electric  plant 
in  the  forest  about  six  miles  from  the  mines, 
where  wood  is  available  for  a  few  years  at 
about  $2  per  cord.  This  is,  however,  a  tem- 
porary makeshift. 

At  Conchefio  in  the  Saragossa  mine  a  con- 
siderable tonnage  of  about  .'it>30  ore  has  been 
developed  within  the  past  year,  and  several 
hundred  thousand  tons  of  §6  to  $8  rock,  which 
is  just  too  low-grade  to  treat.  The  60-stamp 
mill  is  about  to  be  started  on  the  good  ore. 
The  working  cost  is  not  much  less  than  $10 
per  ton.  At  Pinos  Altos  an  indefinite  (owing 
to  the  caved  condition  of  the  mine)  tonnage  of 
ore  of  about  $6  grade  could  be  profitably 
treated  with  cheap  power.  A  40-stamp  mill 
exists  and  there  is  talk  of  trying  to  run  within 
the  next  year  or  so.  Both  this  ore  and  that 
of  Conchefio  show  good  recovery  by  sand- 
leaching  with  cyanide,  say,  about  80% ;  and 
90%  or  better  can  be  extracted  by  sliming  and 
filtering.  The  ores  carry  almost  equally  well 
in  gold  and  silver,  the  gold  being  mostly  free 
and  the  silver  asargentite,  with  more  complex 
sulphides,  sulph-arsenides  and  sulph-antimo- 
nides.     There  is  little  or  no  copper. 

Candamena  is  quite  a  different  proposition. 
The  ores  are  chiefly  valuable  for  silver,  but 
they  are  base  and  complex,  having  pyrite, 
galena,  sphalerite,  and  copper  as  tetrahedrite 
and  tennantite.  Hence  the  camp  has  been 
slow  in  development,  though  there  are  several 
mines  in  Candamena  that  show  quite  high- 
grade,  though  small,  veins.  At  Socorro  the 
ores  are  gold-bearing  only.  The  veins  are 
small,  with  an  occasional  bonanza.  High- 
grading  '  or  stealing  is  common — too  much  for 
the  amount  of  ore.  The  International  Gold 
Mines  Co.  has  a  beautiful  plant  at  Socorro, 
but  not  enough  ore  to  operate  profitably,  so  it 
had  to  be  shut-down.  At  Cienega  a  little 
farther  west,  individuals  have  de\eloped  a  fine 
little  mine  from  virgin  ground.  This  mine — 
the  Cienega — will  show  a  nice  profit  if  care- 
fully worked.  It  also  is  straight  gold,  and  has 
had  the  distinction  of  paying  its  way  from  the 
start  first  with  an  arrastra  and  then  with  five 
stamps.     At  La  Republica — farther  west  still 


114 


THE    MINING    MAGAZINE 


— a  high-grade  shoot  of  silver  ore  is  being 
worked,  but  it  involves  the  handling  of  more 
water  than  any  other  mine  in  the  upper  Sierras. 
They  mill  ore  running  up  to  $50  per  ton  and 
show  only  a  small  operating  profit. 

MELBOURNE. 

The  Tanami  goldfield  in  northwestern 
Australia  has  not  developed  rich  ore  and  con- 
sequently, owing  to  its  inaccessibility,  it  is  one 
of  the  regions  that  will  have  to  await  the  spread 
of  civilization.  The  Warden,  Lionel  C.  E. 
Gee,  is  one  of  the  pioneers  of  industry  in  the 
great  desert  country  of  Australia.  As  showing 
the  type  of  man  he  is,  when  he  contracted 
beri-beri,  an  ailment  prevalent  in  the  high- 
lands of  Central  Australia,  he  never  shirked 
the  performance  of  his  duties.  The  disease  is 
accompanied  by  a  swelling  of  the  legs,  and  if 
it  extends  upward  and  touches  the  heart,  death 
is  almost  instantaneous.  In  Mr.  Gee's  case 
the  swelling  had  reached  the  thighs,  but  as  he 
put  it  :  "a  man  can  only  die  once."  He  was 
in  no  pain  and  work  had  to  be  done,  so,  al- 
though he  did  not  know  the  moment  that  his 
heart  might  be  affected,  he  was  carried  to  the 
Warden's  Court,  where  he  fulfilled  his  duties 
as  serenely  as  if  the  hand  of  death  were  not 
half-extended  toward  him.  Mr,  Gee  has  is- 
sued a  report  upon  the  Tanami  field  in  which 
he  says  that  personally  the  place  interested  him 
very  much,  and  its  possibilities  impressed  him 
strongly  and  favourably,  which  impression 
time  and  further  acquaintance  with  the  held 
had  deepened.  AUuvialgold-diggers  and  speci- 
men-hunters, he  said,  are  proverbially  secre- 
tive, but  he  ascertained  that  up  to  the  end  of 
the  year  1909,  about  six  months  of  intermittent 
work  by  a  handful  of  men  had  produced  over 
1000  ounces  of  gold,  the  value  of  which  he  esti- 
matedatabout^4000.  Thisincludedspecimens 
and  alluvial  gold,  the  largest  nugget  weighing 
11  oz.  17dwt.  As  a  matter  of  fact  no  profit- 
able alluvial  ground  has  been  discovered  ex- 
cept the  small  area  known  as  '  The  Patch  '  on 
the  Reward  claim  and  the  twoadjoining  blocks. 
The  workings  are  situated  3  miles  eastward 
from  what  are  known  as  the  '  rock-holes.' 
These  rock-holes  are  in  a  deep  gorge  of  a  large 
cliff-like  formation.  They  are  difficult  of  ac- 
cess and  only  contain  a  limited  supply  of  water, 
and  the  quality  not  too  good  at  that.  However 
a  good  supply  of  water  was  struck  later  by 
sinking  about  150  ft.  six  miles  north.  Laurie, 
one  of  the  leading  prospectors,  showed  Mr. 
Gee  some  fine  specimens  from  the  Reward 
claim.  About  67  lb.  weight  of  ore  from  the 
claim  adjoining  Laurie's  protected  area  yielded 


100  oz.  gold.  Little  in  the  way  of  prospecting 
work  has  been  done,  but  by  pot-holes  and  cos- 
teens  the  mmeral  belt  is  proved  to  strike  about 
N  35°  E.  The  formation  consists  of  quartz, 
gossany  quartz,  ironstone, and  felsitic  dikes.  It 
is  evidently  of  considerable  width.  At  Laurie's 
claim  it  has  been  traced  on  the  surface  100 
yards  wide,  and  appears  to  dip  northwest.  It 
is  generally  believed  that,  on  crossing  the 
watershed  of  the  Victoria  river  southward,  the 
fever  country  is  left  behind,  for  then  the 
steamy  heat  so  associated  with  fever  gives 
place  to  a  dry  clear  heat,  the  fever  attacks 
from  which  some  of  the  men  suffered  and  in 
some  cases  died,  being  considered  to  be  returns 
of  fever  contracted  farther  northward.  As  far 
as  can  be  judged,  December,  January,  and 
February  are  months  of  intense  and  continuous 
heat  at  Tanami,  the  thermometer  ranging"  from 
100°  to  112°  in  the  shade  most  of  the  time. 
However,  the  heat  is  dry,  burning,  clear,  and 
not  unhealthy,  with  every  day  a  breeze  of  vary- 
ing strength  from  the  southeast.  Owing  to  the 
elevation  of  the  country  the  nights  are  cool, 
making  sleep  natural  and  refreshing.  Mr.  Gee 
comments  on  the  wonderful  brilliancy  of  the 
stars  in  that  clear  atmosphere,  and  adds  that 
Halley's  comet  was  a  magnificent  and  awe- 
inspiring  sight,  stretching  about  45°  across  the 
sky. 

Mining  Accidents. — The  state  of  New 
South  Wales  some  time  ago  decided  that  it 
would  establish  a  fund  for  the  relief  of  miners 
who  might  meet  with  accidents,  both  em- 
ployers and  workmen  contributing  to  the 
fund,  in  addition  to  the  Government.  The 
payment  per  man  is  4id.  per  week,  or  say 
^1  per  annum,  and  for  each  man  the  em- 
ployer has  to  pay  10s.  per  annum,  and  the 
Government  adds  a  similar  amount.  The 
scheme  is  somewhat  on  the  lines  of  the  Lloyd 
George  scheme  of  national  insurance.  The 
fund  has  been  in  existence  about  10  years 
and  has  proved  a  magnificent  success.  Dur- 
ing that  period  381  adult  relatives  of  persons 
killed  received  benefits  for  more  or  less  ex- 
tended periods,  and  306  claims  are  still  opera- 
tive ;  in  addition,  benefits  have  been  paid  in 
respect  of  over  1000  children.  The  total 
number  of  non-fatal  accidents  during  the  ten 
years  was  45,108.  Altogether  over  ^"23 1,000 
was  paid  in  benefits.  In  the  case  of  death 
resulting  from  accident  any  senior  dependent 
on  the  deceased  receives  8s.  per  week,  and 
2s.  6d.  per  week  in  respect  to  any  children 
under  the  age  of  14  years  left  by  deceased. 
An  allowance  of  /^12  is  made  for  funeral  ex- 
penses.    In  the  case  of  the  employee  being 


AUGUST,    1911 


115 


incapacitated  from  attending  to  his  ordinary 
duty,  he  receives  12s.  per  week  while  so  dis- 
abled. What  these  benefits  represent  will  be 
readily  appreciated  by  those  who  have  had 
experience  in  mining  centres.  Haphazard 
collections  and  spasmodic  charity  provide,  as 
a  rule,  quite  inadequately  for  those  who  may 
have  had  the  misfortune  to  lose  the  bread- 
winner, or  to  suffer  personal  permanent  dis- 
ablement. An  actuarial  examination  as  to 
the  condition  of  the  fund  was  made  as  on 
April  30,  1910,  taking  into  review  the  records 
for  over  9  years.  An  extract  from  the  report 
is  of  interest :  The  following  annual  rates  per 
1000  miners  are  deduced  from  the  experience 
of  the  fund,  relating  to  a  total  of  221,863 
miners  for  one  year. 

Per  1000 
per  annum 

Miners  killed  by  accident 2'344 

Widows  and  dependent  adults 1  '623 

Children,  fatal  cases 3*119 

Children,  disablement  cases..      1 '  1 63 

4"2S2 

Miners  permanently  disabled 0'965 

Miners  temporarily  disabled 183*000 

The  balance-sheet  for  last  year  shows  how 
the  scheme  works.  The  amount  deducted 
from  wages  was  ^23,728  and  the  owners'  con- 
tributions amounted  to  ;^11, 174,  the  subsidy 
by  the  Government  being  the  same.  Allow- 
ances to  beneficiaries  absorbed  ;^35,565,  and 
managerial  expenses  about  ;^1500,  leaving  a 
cash  balance  of  ^259,000,  of  which  ;^257,000 
is  invested  for  the  benefit  of  the  fund. 

Queensland. — The  official  figures  giving 
the  mineral  production  of  Queensland  show 
that  the  total  income  from  this  source  for  the 
year  was  /"S, 710,222,  or  ^53,658  more  than 
in  1909.  The  decline  in  the  gold  yield  con- 
tinues, this  year's  return  being  ^Tl, 874, 955, 
or  ^60,220  less  than  a  year  ago.  Unfortu- 
nately, developments  have  notresulted  in  much 
promise  of  this  metal  increasing  its  propor- 
tion of  the  total  mineral  return.  However 
the  success  that  has  attended  to  re-opening  of 
the  outside  mines  at  Charters  Towers  en- 
courages the  hope  that  attention  may  be  pro- 
fitably turned  to  parts  of  the  district  outside 
the  small  area  in  which  work  has  previously 
been  centred.  The  most  interesting  feature 
in  the  return  is  the  growth  of  the  copper  pro- 
duction since  1901.  During  this  time  the 
value  of  the  copper  output  has  increased  from 
;^194,227  to  ^932,489.  The  smelting  industry 
has  become  the  mainstay  of  the  Queensland 
mineral  production,  a  large  proportion  of  the 


gold  and  most  of  the  silver  coming  from  this 
source.  Of  last  year's  gold  output  30%  came 
from  metallurgical  works.  The  new  Hamp- 
den-Mount  Elliott  railway  was  particularly 
beneficial  to  an  important  copper-gold  district, 
and  a  large  railway  construction  scheme  now 
announced  by  the  State  Government  promises 
much  in  further  developing  the  mining  in- 
dustry. 

Mount  Elliott.— The  smelter  at  the  Mount 
Elliott  copper  mine,  Queensland,  is  to  be  shut- 
down for  two  months,  August  and  September. 
The  reason  for  this  is  that  a  vugh  channel  has 
disturbed  the  course  of  the  ore  at  the  No.  3 
level,  extending  to  the  No.  1  and  2  levels,  and 
the  management  thought  it  best  to  shut-down 
the  smelters  while  the  necessary  repairs  were 
made  underground.  A  'vugh  '  is  a  large  cavity 
m  a  lode,  and  is  practically  what  a  cavern  is 
in  mother  earth.  Usually  these  vughs  are  of 
insignificant  size  but  this  one  extends  upward 
something  like  200  ft.  A  couple  of  years  ago 
a  short  run  with  the  old  smelter  gave  about 
;^60,000  worth  of  copper.  Then  it  was  de- 
cided to  erect  a  larger  plant,  and  the  present 
operations  have  maintained  a  satisfactory  out- 
put since  the  smelting  started  in  September 
last.  For  the  nine  months  ended  on  May  31 
the  company  treated  38,193  tons  of  ore  for 
4866  tons  of  copper,  9095  oz.  gold,  and  5116 
oz.  silver,  representing  a  total  value  of  about 
;^280,000,  and  leaving  a  handsome  profit.  The 
company  has  spent  a  lot  of  money  in  mine  de- 
velopment and  installation  of  smelters,  besides 
the  construction  of  the  railway,  which  the 
Government  has  now  taken  over,  repaying 
the  outlay  incurred.  The  ore  reserves  at 
Mount  Elliott  have  been  estimated  to  contain 
metals  to  the  value  of  over  a  million.  The 
diamond-drill  bores  have  not  yet  cut  any  large 
bodies  of  ore  in  the  deeper  ground,  but  as  the 
lode  is  erratic,  it  is  more  than  likely  that  the 
ore  has  been  missed.  Much  dissatisfaction 
was  expressed  by  shareholders  in  Australia 
because  the  directors  in  London  did  not  issue 
this  information  here  at  the  same  time  as  in 
London. 

Chillagoe. — The  directors  of  the  Chillagoe 
company  have  been  making  a  tour  of  their 
mining  properties  in  Northern  Queensland. 
This  company  is  largely  backed  by  British 
capital,  which  has  provided  the  best  part  of  a 
million  pounds  for  the  mines,  railways,  and 
works.  The  directors  visited  the  Chillagoe 
and  the  other  mining  districts  in  which  the 
company  has  become  interested,  chiefly  along 
its  250  miles  of  railway.  These  include  the 
Etheridge  and  Oaks  goldfields,  and  it  is  more 


116 


THE    MINING    MAGAZINE 


than  likely,  owing  to  the  discovery  of  coal  at 
Mount  Milligan,  they  will  shortly  embrace  the 
Hodgkinson  goldfield  as  well.  They  expressed 
themselves  well  pleased  with  their  visit,  and 
with  the  prospects  throughout  the  area  in- 
spected by  them.  Among  the  mines  acquired, 
the  Nil  Desperandum,  Queenslander,  Have- 
lock,  and  Big  Reef  have  been  formed  into  a 
separate  company,  under  the  same  manage- 
ment, called  the  Etheridge  Mines,  Ltd.,  with  an 
available  working  capital  of  ^^33,000.  A  con- 
centration plant  is  to  be  at  work  by  the  end  of 
the  present  year.  The  ore  is  highly  mineral- 
ized and  while  unsuitable  for  ordinary  battery 
treatment,  is  amenable  to  concentration. 

CAMBORNE. 

Wheal  Kitty  &  Penhalls  is  as  usual  the 
first  of  the  Cornish  companies  to  issue  the 
half-yearly  report  and  statement  of  accounts. 
The  profit  for  the  six  months  ended  June  30 
was  ;^1876,  and  dividends  of  5  and  10%  respec- 
tively were  declared  on  the  ordinary  and  pre- 
ference shares.  The  working  cost  is  up  seven- 
pence  per  ton  and  now  stands,  including  royal- 
ties of  Is.  5d.  per  ton,  at  slightly  over  25s. 
The  increase  is  largely  due  to  the  higher 
wages  paid,  owing  to  the  dearth  of  miners  in 
the  district  and  to  the  competition  consequent 
on  the  enlarged  scale  of  operations  on  adjacent 
properties.  The  equipment  of  Sara's  shaft  to 
the  540  ft.  level  is  nearing  completion,  and  the 
65  in.  Cornish  engine  with  18  in.  pitwork 
should  handle  all  the  water  likely  to  flow  into 
these  workings.  A  cross-cut  south  from  this 
shaft  toward  the  old  mine  has  recently  inter- 
sected the  Stamps  lode  on  the  other  side  of 
the  main  cross-course  ;  at  the  point  of  inter- 
section it  is  18  in.  wide  and  averages  84  lb.  per 
lb.  per  ton.  A  large  amount  of  ground  on  this 
lode  will  now  be  available  for  development. 
Its  discovery  definitely  proves  the  heave  of 
the  main  cross-course,  and  it  is  clear  that  the 
shaft  will  not  have  to  be  sunk  so  deep  as  was 
expected ;  in  fact  another  24  fm.  of  sinking 
should  reach  the  Wheal  Kitty  lode,  for  which 
the  shaft  is  mainly  being  sunk. 

East  Pool  &  Agar. — The  accounts  for  the 
past  quarter  presented  to  the  shareholders  at 
their  meeting  on  August  8,  show  a  profit  of 
;^90.  The  dues  payable  to  Mr.  Basset  on  the 
East  Pool  section  amounting  to  ;^203  have 
not  been  charged,  as  that  amount  has  been 
contributed  by  the  '  lord  '  to  the  sinking  of  the 
engine  shaft.  This  is  a  misleading  way  of 
dealing  with  the  matter  in  the  accounts,  where 
the  cost  per  ton  is  shown  to  be  lower  than  it 
really  is.     In  the  case  of  the  Wheal    Agar 


section,  dues  payable  to  Viscount  Clifden 
amounting  to  ;^65  are  charged.  The  develop- 
ment work  continues  to  be  ridiculously  small 
for  a  mine  with  an  output  of  over  50,000  tons 
per  annum.  For  the  quarter  under  review, 
243  ft.  of  ground  was  opened  up,  which  is  a 
reduction  on  the  previous  12  weeks,  but  as 
all  available  funds  are  being  spent  on  shaft 
repairs  and  pump-work  at  Agar,  the  managers 
are  in  a  difficult  position  in  this  respect.  It 
however  shows  clearly  one  of  the  weak  points 
in  the  cost-book  system  as  applied  to  a  large 
mine,  for  if  vigorous  development  had  been 
continued  for  the  past  12  months  the  company 
would  by  this  time  have  been  reaping  the  re- 
sults and  taking  full  advantage  of  the  high 
price  of  tin.  By  the  time  the  repairs  to  the 
shaft  and  the  pump-work  are  completed,  tin 
may  have  had  a  fall  and  then  the  shareholders 
will  '  feel  a  draught.'  Had  the  committee  of 
management  had  the  pluck  to  make  small 
calls  to  provide  funds  for  development,  by 
this  time  the  price  of  the  shares  would  be 
much  higher  than  at  present,  and  what  is 
more  the  rise  would  have  been  justified.  The 
tonnagecrushedwasl3,722,andthe  production 
1  IOt  tons  of  black  tm,  the  average  recovery  of 
tin  and  wolfram  being  19  lb.  per  ton  treated. 

Grenville  United. — The  accounts  of  this 
company  are  being  awaited  with  interest,  for 
the  news  from  the  property  is  distinctly  cheer- 
ing. The  produce  per  ton  has  risen  by  8^  lb. 
per  ton  since  March  last,  and  the  sales  by 
131  tons  of  black  tin,  while  the  receipts  have 
increased  nearly  ^1900  per  month.  The 
profits  per  month  of  four  weeks  are  now  pro- 
bably not  less  than  ^^2000.  The  manager's 
return  to  the  old  method  of  giving  monetary 
values  to  the  stopes,  etc.,  is  to  be  regretted,  for 
this  method  is  not  illuminating  to  the  average 
shareholder.  Pounds  per  ton  is  the  only  in- 
telligible way  of  reporting  tin-lode  contents, 
for  this  enables  the  shareholder  to  appraise  the 
value  for  himself.  Such  a  relapse  on  the  part 
of  Captain  Battens  is  inexplicable,  for  he  has 
introduced  several  improvements  in  the  busi- 
ness management  of  Grenville  since  his  ap- 
pointment. It  IS  to  be  hoped  that  some  share- 
holder will  protest  at  the  forthcoming  meeting 
of  the  company. 

At  Gossmoor  the  new  steam-plant  is  to 
be  formally  started  next  week.  A  trial  run 
has  been  satisfactory  and  it  is  to  be  hoped  that 
the  result  may  be  to  establish  a  successful 
alluvial  proposition  in  Cornwall.  J.  H.  Collins, 
who  first  tested  the  ground,  is  confident,  with 
the  price  of  tin  much  lower  than  at  present, 
that  the  business  will  be  profitable. 


AUGUST,    1911 


117 


NEW  YORK. 

Market  quotations  on  mining  stock,  if 
they  truly  represented  the  condition  of  the  in- 
dustry, would  justify  the  most  acute  appre- 
hension. For  no  discoverable  reason  relating 
to  the  actual  condition  of  the  properties,  the 
shares  of  such  old  reliables  as  Anaconda  and 
Tennessee  Copper  have  suffered  severely  with- 
in the  past  month,  the  actual  losses  being : 
Amalgamated,  4i  ;  A.  S.  &  R.,  3  ;  Chino,  1}  ; 
Miami,  f ;  Nevada  Consolidated,  Ij;  Ray,  1  ; 
Tennessee,  I2  :  Utah  Copper,  2  points.  These 
falling  prices  were  registered  during  periods 
when  trading  threatened  to  disappear  entirely  ; 
in  fact,  a  new  low  level  for  a  day's  volume  of 
transactions  has  been  recorded  within  the 
month.  As  to  the  sudden  and  spectacular  drop 
in  Nipissing,  this  is  generally  explained  by  the 
possibility  of  the  next  customary  extra  divi- 
dend being  omitted,  but  the  real  reason  is  that 
a  few  of  the  principal  holders  of  the  stock  were 
under  the  necessity  of  realizing  immediate 
cash.  As  in  the  case  of  other  shares,  the  drop 
is  not  taken  to  reflect  on  the  earning  ability  of 
the  property. 

Reciprocity  with  Canada  now  seems  to  be 
assured.  The  Senate  has  at  last  acquiesced 
in  the  popular  demand  for  better  trade  rela- 
tions, and  the  United  States  now  stands  com- 
mitted to  its  side  of  the  contract.  In  Canada, 
a  certain  amount  of  opposition  appeared  in  the 
Legislature,  and  developed  to  such  an  extent 
as  to  lead  the  Governor- General,  with  the  ad- 
vice of  the  Premier,  to  dissolve  Parliament. 
Elections  on  the  single  issue  of  reciprocity 
will  occur  in  September,  and  the  present  in- 
dications are  that  it  will  be  supported  by  a 
decided  majority.  In  that  event,  the  actual 
provisions  of  the  treaty  will  go  into  effect  about 
next  November.  Aside  from  the  general  public 
advantage  of  cheaper  supplies  of  food  to  be 
secured  from  Canada,  our  interest  lies  princi- 
pally in  the  importation  of  lead  ore  and  bullion 
from  British  Columbia,  iron  ore  from  Ontario, 
and  coal  from  Nova  Scotia,  the  last  being  re- 
ceived with  special  gratitude  by  manufacturers 
in  New  England.  The  Pacific  Coast,  like- 
wise, will  enjoy  the  advantage  of  cheaper  coal 
from  Vancouver  island  and  the  Canadian 
Rockies. 

The  American  Smelting  &  Refining  Co. 
reports  for  the  year  ending  April  30,  1911,  that 
its  total  net  earnings,  after  allowing  $750,000 
for  depreciation,  amounted  to  $6,660,000,  out 
of  which  $5,500,000  was  distributed  in  divi- 
dends. In  the  12  years  of  its  existence,  the 
company  has  paid  dividends  amounting  to 
$58,463,000,  and  has  accumulated  a  surplus 


of  $17,640,000,  after  spending  $10,000,000 
for  repairs  and  replacements,  and  allowing 
$7,600,000  for  depreciation,  including  new 
construction.  The  present  value  of  the  com- 
pany's property  is  estimated  at  $75,000,000, 
and  of  its  investments  in  the  securities  of  other 
concerns,  at  $18,086,000  ;  its  current  assets  at 
the  end  of  the  year  were  $22,360,000.  The 
net  income  was  $380,000  less  than  that  of  the 
preceding  year,  due  partly  to  an  increase  in 
the  amount  written  off  for  depreciation,  and 
partly  to  diminished  income  from  mining  oper- 
ations ;  the  company's  mines  are  all  in  Mexico 
and  are  not  worked  except  when  necessary  to 
offset  deficiencies  in  the  supply  of  custom 
ore.  By  the  purchase  of  122,500  outstanding 
shares  at  $60,  the  Smelting  &  Refining  Co. 
now  owns  the  entire  ^30,000,000  common 
stock  of  the  American  Smelters  Securities  Co. ; 


Chinipas,  Mexico. 

the  other  obligations  of  the  Securities  Com- 
pany include  $47,000,000  of  preferred  stock 
and  $15,000,000  of  6%  bonds.  In  a  similar 
manner,  the  Smelting  &  Refining  Co.  during 
the  past  year  secured  entire  ownership  of  the 
United  States  Zinc  Co.,  and  a  larger  interest 
in  the  National  Metallurgical  Company  of 
Mexico.  It  likewise  paid  off  the  last  of  the 
bonds  of  the  Omaha  &  Grant  smelter  and  now 
has  no  bonded  indebtedness  against  any  of  its 
property.  Thecompany's  smelting  plants  have 
a  combined  capacity  of  5,500,000  tons  and  its 
refineries  of  460,000  tons  per  year.  1  ts  control 
of  the  Smelters  Securities  company  also  gives 
it  an  additional  smelting  capacity  of  2,650,000 
tons  of  ore,  and  a  further  refining  capacity  of 
190,000  tons  per  year. 

The  copper  market  remains  firm,  but  it 
is  hopeless  to  expect  any  marked  or  general 


118 


THE    MINING    MAGAZINE 


advance  in  prices.     It  is  equally  improbable 
that  prices  will  drop  much  below  their  present 
level,  in  spite  of  the  anticipated  additions  of 
metal  from  new  sources.     Careful  estimates 
on  the  capacities  of  the  forthcoming  producers 
indicate  that  the  output  for  1912  will  exceed 
that  of  the  present  year  by  about  200,000,000 
lb., or  approximately  10*^01  the  normal  present 
production.   After  this  shall  have  been  accom- 
plished,   no   further   sudden    increase    in    the 
world's  production  is  to  be  anticipated,  as  no 
large  copper  -  bearing   territories   other  than 
those  included  in  the  foregoing  estimates  are 
at    present    under    exploitation.        A    certain 
amount  of  encouraging  exploration   is  going 
on  in  Central  Africa,  but  it  will  be  many  years 
before  metal  comes  from  there  in  quantity.   It 
is  now  generally  conceded  that  the  expected 
influence  of  the  '  porphyry  '  production  on  the 
market  was  greatly  over-estimated.     The  por- 
phyry copper  has  made  its  appearance  so  gra- 
dually that  the  market  has  been  able  to  ab- 
sorb it  without  signs  of  distress;  consumers 
waited  a  long  time  for  the  distress  to  occur, 
but  finally  became  convinced  that  prices  could 
be  maintained  at  no  lower  level.      Miami  and 
Ray  are  now  producing,  and  Chino  will  begin 
before  the  end  of  the  year.     The  managers  of 
the  Braden  mine  expect  to  have  the  first  sec- 
tion of  the  3000-ton  mill  in  operation  shortly; 
the  second  section  will  be  started  in  October, 
and  the  third  in  December,  if  nothing  fails. 
They  have  been  experimenting  on  a  leaching 
process,  and  speak  rather  confidently  of  7-cent 
copper.     At  full  capacity,  they  count  on  pro- 
ducing 37,000,000  lb.  per  year.      In  this  con- 
nection, an  interesting  technical  point  has  been 
brought  out  at  the   Miami  mill.      The   fine- 
crushing  rolls  installed  in  section  No.  4  for 
some  reason  failed  to  yield  the  expected  re- 
sults; a  certain  amount  of  rubbing  action  seems 
to  be  required  to  liberate  all  the  chalcocite  in 
the  ore,  which  the  rolls  do  not  give.      In  sec- 
tions No.  5  and  6,  therefore,  the  old  reliable 
Chilean  mills  are  being  installed,  while  section 
No.  4  is  being  retained  as  an  experimental 
laboratory,  and  is  now  being  equipped  with  a 
large    Hardinge   mill   to  replace  half   of  the 
rolls.     Miami  hopes,  in  the  near  future,  to  be 
treating  3000  tons  daily. 

Calumet  &  Hecla  consolidation  is  not 
yet  off  the  rocks.  The  latest  obstacle  is  a 
temporary  injunction  against  the  consolida- 
tion granted  by  a  County  Circuit  Court  in 
favour  of  minority  stockholders  ot  the  Osceola 
company,  on  the  ground  that  the  State  statutes 
forbid  the  formation  of  a  merger  involving 
capital  in  excess  of  $10,000,000.   Seven  other 


copper  companies,  and  a  decided  majority  of 
the  Osceola  company,  had  already  voted  in 
favour  of  the  proposed  consolidation.     The 
dissentient  minority  is  therefore  a  small  one. 
Governmental  restraint  of  the  big  cor- 
porations IS  fast   becoming  a  settled  policy, 
and  it  is  none  too  soon.     Already  the  Standard 
Oil  Co.  has  promised  to  disband  into  its  34 
constituent  elements  by  December  1  of  this 
year.     The    Tobacco    Trust    is   expected   to 
follow  suit,  as  a  result  of  its  trial  before  the 
Supreme   Court.     Although   there   is   no  or- 
ganized wire  trust,  a  large  number  of  manu- 
facturers of  steel  wire  and  wire  products  were 
brought  to  court,  individually,  within  the  past 
month,  and  were  fined  §1000  each   for  con- 
spiracy to  monopolize.     Action  has  been  be- 
gun against  the  Lehigh  \'alley  Railroad  Co. 
to  compel  it  to  dissociate  itself  from  the  Lehigh 
Valley  Coal  Co.  incompliance  with  the  Hep- 
burn law  forbidding  transportation  companies 
to   own    stock    in   coal    mines.     The    Lehigh 
Valley  is  only  one  of  many  railroads  in  Penn- 
syKania  under  suspicion  in  this  regard.    The 
activities  of  the  Sugar  Trust  and  of  the  Steel 
Trust  are  now  under  investigation  by  Con- 
gress, and  the  Lumber  Trust,  the  Paper  Trust 
and  the  '  Money'  Trust  have  been  mention- 
ed as  appropriate  candidates  for  inquisition. 
While  all  this  official  interference  with  busi- 
ness matters  is  highly  distasteful  in  a  demo- 
cratic country,  as  savouring  too  strongly  of 
Socialism,  still  it  seems  to  be  the  only  way 
by  which,  under  our  form  of  government,  the 
humble  consumer  of  Trust  products  can  pro- 
tect himself.     The  Trusts  have  been  permit- 
ted to  grew  to  their  present  appalling  propor- 
tions partly  through  lax  enforcement  of  the 
laws    controlling    them,   but    principally    be- 
cause they  have  been  protected  from  foreign 
competition,   and   they    have    only    to   thank 
their  own  highhandedness   and  disregard   of 
business  morality  if  the  people  are  now  turn- 
ing against    them.     As    to  the   Steel  Trust, 
however,  this  complication  arises  :  The  U.  S. 
Steel  Corporation,  by  virtue  of  its  centralized 
ownership  of   iron   mines,   coal   mines,  lime- 
stone  quarries,  coke    ovens,  blast   furnaces, 
steel  mills,  and  railroads,  can  produce  steel 
products  for  several  dollars  per  ton  less  than 
the  independent  steel  manufacturers,  in  spite 
of  its  much  heavier  interest  charges.     If,  then, 
it  were   to  cut  prices  to  yield  what  others 
would  consider  a  satisfactory  profit,  the  in- 
dependent concerns  would  have  to  go  out  of 
business    forthwith.     It  is    not   always    that 
magnificent    profits    go    hand    in   hand    with 
philanthropy. 


AUGUST,    1911 


119 


Miiimi,  Arizona. 


Hie  China  Copper  Mine,  New  Mexico. 


TWO  GREAT  LOW-GRADE  COPPER  MINES. 


120 


THE    MINING    MAGAZINE 


METAL  MARKETS 

COPPER. 

Average  prices  of  cash  standard  copper : 
July  June  July 

1911.  1911.  1910. 

;^56.  15s.  6d.  £5^.  9s.  lOd.  £b\.  5s.  6d. 
It  is  not  too  md'ch  to  say  that  consump- 
tion on  this  side  of  the  Atlantic  is  phenomenal 
and  every  branch  of  the  copper  trade  is  enjoy- 
ing the  benefit  of  enormous  demand  and  cheap 
prices.  The  one  fear  in  the  minds  of  the 
speculative  public  is  that  such  an  increasing 
absorption  of  the  metal  here  cannot  continue 
amid  the  unrest  in  labour  circles,  so  that  un- 
less American  trade  expands  further  improve- 
ment is  barred.  The  June  American  Pro- 
ducers figures  were  not  received  with  favour 
by  the  market  for  this  reason,  and  their  pub- 
lication was  followed  by  the  liquidation  of 
some  bull  accounts  and  by  some  bear  selling, 
a  movement  which  continued  throughout  the 
month  and  brought  prices  down  gradually  to 
;£'56.6s.  3d.  cash  and  £5(i.  18s.  9d.  3  months. 
No  pronounced  weakness  has  been  shown, 
mainly  on  account  of  the  firm  attitude  of  the 
leading  American  producers  who  appear  to  be 
once  more  accumulating  stocks.  The  crop 
situation  gives  cause  for  hopeful  views  of  the 
future,  but  the  position  is  much  obscured  by 
the  uncertainties  of  a  tariff-revision  campaign 
and  the  government  prosecutions. 

TIN. 

Average  prices  of  cash  tin  : 

July  June  July 

1911.  1911.  1910. 

;6'193.  2s.  Od.      ;^207.  7s.  9d.       ;^149.  2s.  Id. 

Except  for  the  customary  preparations  in 
anticipation  of  the  Banka  sale  late  in  the 
month,  the  market  was  left  without  any  marked 
manipulation  either  by  the  syndicate  or  its 
opponents.  Business  consequently  has  been 
restricted,  fluctuations  have  become  narrower, 
and  prices  depressed.  At  one  time  the  mar- 
ket became  almost  demoralized  under  pressure 
of  sales  by  holders  of  near  dates,  and  prices 
declined  to  ;^188.  10s.  cash  and  ^182  for- 
ward. At  this  point,  however,  the  syndicate 
lent  support,  and  a  rally  quickly  followed  to 
;^192.  10s.  cash  and  /"185.  10s.  forward.  Vio- 
lent fluctuations  succeeded  and  the  tendency 
became  sensitive.  At  the  Banka  sale  2478 
tons  was  sold  at  an  average  of  ^"189.  The 
market  leaders  had  prepared  themselves  for 
this  by  freely  selling  cash  tin  and  buying  3 
months  tin,  whereby  the  backwardation  was 
reduced  at  one  time  to  £2. 


The  consumers'  demand  is  excellent  and 
they  have  bought  freely  as  prices  receded. 
The  Americans,  who  have  been  withholding 
orders,  are  now  taking  a  renewed  interest,  and 
substantial  transactions  in  the  East  at  high 
prices  are  believed  to  be  for  their  account. 
Tinplate  makers  are  working  at  pressure  and 
new  works  are  contemplated  in  South  Wales. 

LEAD. 

Average  prices  of  soft  foreign  lead  : 
July  July  July 

1911.  1911.  1910. 

;^13.  10s.  lid.      i:i3.  5s.  5d.      ;^12.  lis.  8d. 

Prices  advanced  substantially  toward  the 
end  of  the  month.  In  the  earlier  part  supplies 
came  along  in  such  volume  as  to  disguise  the 
strong  position  of  the  metal  and  so  kept  prices 
from  rising.  It  has  been  suddenly  realized 
that  supplies  in  all  parts  of  the  world  are  ex- 
hausted and  an  increase  in  output  impossible. 
Buyers  have  been  quick  to  appreciate  the 
altered  position  and  are  buying  ahead  to  an 
extent  to  which  the  market  has  not  been  ac- 
customed for  years. 

SPELTER. 

Average  prices  of  good  ordinary  brands : 
July  June  July 

1911.  1911.  1910. 

^"24.  13s.  lOd.       ;^24.  9s.  7d.       ;^22.  5s.  6d. 

The  scarcity  of  this  metal  is  causing  great 
concern  to  the  English  galvanizers.  For  an 
advance  in  price  they  are  prepared,  but  the 
limited  quantities  doled  out  by  the  Convention 
to  the  English  market  renders  it  impossible  to 
feel  secure  about  procuring  their  raw  material. 
Much  indignation  is  being  expressed  by  the 
trade  at  the  action  of  the  producers  in  cutting 
off  supplies.  Proposals  have  even  been  pro- 
jected by  prominent  users  to  erect  works  near 
Liverpool  and  produce  their  own  spelter. 

OTHER  METALS  AND  MINERALS. 

Prices  quoted  on  August  10  : 

Silver. — 24id.  per  oz. 

Platinum. — 172s.  6d.  per  oz. 

Bismuth. — 7s.  6d.  per  lb. 

Aluminium. — £(i\  per  ton. 

Nickel. — ;^169  per  ton. 

Cobalt. — 9s.  9d.  per  lb. 

Antimony. — £21  per  ton. 

Quicksilver. — £^  per  flask  of  75  lb. 

Manganese  Ore. — 9d.to9id.  per  unit  (1%). 

Iron  Ore. — Cumberland  hematite  19s.  6d. 
per  ton  at  mine.    Spanish  19s.  delivered. 

Pig  Iron. — Cleveland  47s.  per  ton.  He- 
matite 62s.  per  ton. 

Wolfram  Ore— 31s.  per  unit  (1%). 


THE   PYRITES   DEPOSITS  OF   HUELVA 

By   H.    F.   COLLINS. 


M 


UCH  has  been  written  in  regard  to 
the  pyrites  masses  of  the  province  of 
Huelva,  Spain,  their  mode  of  occur- 
rence, origin,  and  the  secondary  enrichments 
to  which  they  have  been  subjected,  but  com- 
paratively little  in  regard  to  their  mineralogi- 
cal  composition.  In  general  terms  it  is  mat- 
ter of  common  knowledge  that  these  deposits 
are  interstratified  with  the  schist  and  slate,  or 
occur  at  the  contact  between  these  rocks  and 
acid  or  basic  eruptives,  that  they  are  irregu- 
larly lenticular  in  form,  and  dip  at  high  angles 
together  with  the  rocks  themselves,  and  that 
they  have  been  formed  chiefly  by  replace- 
ments of  crushed  rock  along  shear-zones. 


estimate  of  these  pyritic  masses  relates  'to 
their  supposed  uniformity  m  composition, 
which  in  many  cases  disappears  upon  close 
examination.  It  is  true  that  each  individual 
mine  has  its  current  contracts  for  the  supply 
of  a  given  grade  of  ore,  and  that  the  cargoes 
shipped  in  fulfilment  of  those  contracts  vary 
in  composition  within  narrow  limits,  but 
uniformity  in  the  ultimate  chemical  com- 
position of  large  cargoes  is  in  a  number  of 
the  mines  secured  only  by  careful  mix- 
ing of  different  classes  of  ore  that  differ 
considerably  in  composition.  Thus,  in  the 
case  of  shipments  averaging,  for  instance, 
24%  copper    and   47%    sulphur,    an   average 


50 

I 


100 

J 


_1_ 


200  metres 
_J 


FL,AK   OF  OREBODIES  AT  HUELVA. 


A  study  of  the  conditions  that  have  governed 
the  distribution  of  the  copper  and  other  con- 
stituents throughout  the  masses  has  been  ren- 
dered difficult  by  the  fact  that  the  deposits 
which  have  naturally  attracted  most  attention 
are  those  which,  being  of  the  largest  size,  are 
of  the  greatest  commercial  importance,  namely 
Rio  Tinto  and  Tharsis.  These,  however,  are 
not  typical  but  abnormal,  and  their  relatively 
enormous  size  militates  against  a  clear  idea  of 
their  structure.  The  largerdeposits  are  usually 
more  frankly  lenticular  in  form,  and  less  re- 
semble ordinary  lodes  than  the  smaller  ones, 
many  of  which  present  the  characters  of  a 
series  of  small  lenses  placed  en  echelon  along 
the  line  of  an  irregular  shear-zone,  while 
others  exhibit  a  proportion  between  length 
and  width,  likening  them  to  ordinary  wide 
lodes,  for  example,  1600  ft.  long  by  15  to  100 
ft.  wide  ;  in  another  case  1000  ft.  long  by  6  to 
50  ft.  wide. 

One  of  the  greatest  errors  in  the  popular 
2—4 


may  be  obtained  by  mixing  ore  from  one 
stope  carrying  3i%  copper  and  44%  sul- 
phur with  ore  from  another  containing  only 
lj%  copper  and  50%  sulphur.  Similarly, 
in  the  case  of  ore  supplied  according  to  an- 
other current  contract,  cargoes  that  average 
with  considerable  uniformity  4%  copper  and 
41%  sulphur  are  secured  by  mixing  silicious 
ores  containing  5  to  6%  copper  and  32  to  38% 
sulphur  with  comparatively  clean  pyrite  con- 
taining 2  to  3%  copper  and  44  to  47%  sulphur. 
In  the  orebodies  themselves  great  variations 
in  composition  are  noticeable.  Generally 
speaking,  the  largest  masses  are  the  most 
uniform  in  composition,  but  even  in  the  lar- 
gest of  all  the  variations  in  composition  are 
great,  and  an  enormous  number  of  small 
samples  must  be  taken  over  a  large  number 
of  faces  well  distributed  over  the  whole  area 
of  a  given  level  in  order  to  get  any  reliable 
idea  of  the  average  value  of  the  ore  extract- 
able  from  that  floor.     For  the  sake  of  economy 


121 


122 


THE    MINING    MAGAZINE 


this  is  commonly  done  by  putting  in  small 
blasts  and  blowing  down  a  few  hundredweight 
at  a  large  number  of  points  evenly  distributed 
over  the  whole  area  after  the  mass  has  been 
blocked  out  by  levels  and  cross-cuts ;  and 
although  this  method  is  inferior  to  that  of 
sample  cuts  at  regular  distances,  and  is  liable 
to  give  high  results,  in  practice  the  error  is 
found  to  be  small,  and  the  method  is,  of 
course,  much  cheaper  and  less  laborious  than 
that  of  cuts.  A  good  general  idea  of  the 
value  of  an  orebody  that  has  not  been  devel- 
oped by  cross-cuts  can  be  obtained  by  putting 
in  a  series  of  diamond  drill-holes  transversely 
across  the  mass  to  the  walls  at  regular  dis- 
tances along  a  main  level,  but  the  samples, 
being  small,  are  liable  to  be  unduly  influenced 
by  small  patches  or  veinlets  of  rich  ore. 

In  any  case,  it  is  found  that,  on  a  given 
horizon,  samples  taken  within  a  comparatively 
short  distance  of  each  other  may  vary,  for 
instance,  between  the  limits  of  0'7?^  and  4% 
copper,  and  the  distribution  of  the  rich  and 
poor  patches  is  usually  erratic. 

It  will  generally  be  found,  however,  that 
zones  or  belts  of  richer  or  of  poorer  ore  can 
be  traced  running  parallel  to  the  walls,  and 
often  these  zones  are  well  defined  ;  so  that  in 
a  large  number  of  cases,  perhaps  a  majority, 
it  may  be  said  that  on  a  given  level  the  ore 
near  the  hanging  wall,  for  instance,  is  richer 
in  copper  and  poorer  in  sulphur  than  that  on 
the  foot-wall  side,  or  vice  versa.  In  other 
cases,  no  such  rule  can  be  traced,  and  the 
distribution  of  the  rich  and  poor  ores  appears 
to  be  completely  irregular.  Frequently  the 
dividing  line  between  two  classes  of  ore  in 
the  same  mass  is  clear  and  sharp,  and  some- 
times it  is  marked  by  a  parting  of  slate  of 
varying  thickness.  This  may,  and  probably 
does,  indicate  in  some  cases  that  the  ore  was 
not  found  simultaneously  along  the  two  sides 
of  the  parting,  but  successively.  Sometimes 
the  parting  is  not  only  continuous  throughout 
the  whole  length  of  the  mass,  but  becomes  a 
fairly  thick  wedge  of  slate,  as  shown  in  the 
illustration.  In  such  acasetheinferencemaybe 
drawn  that  the  ore  was  formed  in  two  succes- 
sive parallel  and  over-lapping  lenses  along  the 
same  broad  shear-zone;  and  since  these  pyritic 
lenses  vary  in  width  in  a  vertical  plane  quite 
as  much  as  in  a  horizontal,  one  of  the  lenses 
in  the  over-lapping  portion  is  likely  to  dwindle 
in  depth,  while  the  other  persists  and  perhaps 
even  becomes  wider. 

More  especially  in  the  smaller  lodes,  a 
banded  structure  is  noticeable,  either  through- 
out the  whole  orebody  or  in  that  part  of  it 


near  one  or  other  of  the  walls  —  doubtless 
a  relic  of  the  original  stratification  of  the 
country-rock.  Such  a  banded  structure  is  so 
well  marked  in  one  of  the  smallest  of  the 
pyritic  lode-lenses  as  to  leave  no  doubt  of  the 
gradual  replacement  of  slate  by  pyrite.  The 
hanging-wall  portion  of  the  lode  in  question 
varies  in  the  lenticular  swelling  from  3  to 
15ft.  in  width;  it  is  composed  of  compact 
cupriferous  pyrite  varying  from  43  to  47%  in 
sulphur  and  2  to  5%  in  copper,  the  higher 
percentage  of  copper  accompanying  the  smal- 
ler width,  and  vice  versa.  The  footwall  por- 
tion of  the  lode,  from  3  to  10  ft.  wide,  is  com- 
posed of  alternate  narrow  bands  of  the  same 
class  of  compact  cupreous  pyrite  varying  in 
width  from  tV  inch  up  to  6  inches,  and  of 
generally  broader  bands  of  crushed  and  silici- 
fied  slate  highly  impregnated  with  small  cry- 
stals of  iron  pyrite,  in  proportions  varying 
from  30  up  to  60%  pyrite.  This  impregnated 
slate  contains  from  \  to  1%  of  copper,  not 
however  in  the  crystals  of  pyrite,  but  in  the 
form  of  a  fine  dissemination  through  the  slate 
itself;  the  division  between  the  pyritic  slate 
and  the  ordinary  schist  country  rock  is  sharp, 
and  often,  though  not  invariably,  marked  by 
a  clay  selvage. 

When  a  banded  or  laminated  structure  is 
at  all  marked  in  a  part  of  the  lode  it  will 
usually  be  found  that  not  only  the  copper  but 
also  the  foreign  matters  range  themselves 
along  the  bands  or  laminae.  The  foreign  sub- 
stance of  most  common  occurrence  is,  of 
course,  quartz,  but  blende  and  galena  are 
also  quite  common,  and  frequently  intimately 
mixed.  The  resulting  banded  '  complex  ' 
mineral  may  contain,  as  at  Sotiel  and  Poder- 
osa,  for  instance,  only  2%  Pb  and  4%  Zn,  or 
it  may  contain,  as  at  Monte  Romero,  up  to 
15%  Pb  and  30%  Zn.  Whole  cargoes  have 
been  shipped  from  this  latter  mine  containing 
as  much  as  11%  Pb  and  28%  Zn,  besides  U% 
copper  and  5  oz.  silver  per  ton,  the  copper 
varying  at  the  same  time  from  4  to  4^%  down 
to  li%,  usually  in  inverse  proportion  to  the 
zinc  and  lead. 

Intimate  mixtures  are  found  of  chalcopy- 
rite  and  iron  pyrite  ;  these  may  be  regarded 
as  fine  disseminations  of  the  former  in  a  solid 
solution  of  the  latter,  or  rather  perhaps,  see- 
ing that  in  most  cases  the  iron  pyrite  crystal- 
lized first,  as  a  spongy  aggregate  or  network 
of  fine  crystals  of  pyrite  surrounded  by  a 
greater  or  less  quantity  of  a  solid  solution  of 
pyrite  and  chalcopyrite.  I  have  specimens 
of  ore  from  a  small  lode  running  from  four 
inches   up  to  a  foot   or  fifteen  inches  wide, 


AUGUST,    1911 


123 


which  consists  of  such  a  soHd  solution  or  in- 
timate mixture  of  pyrite  and  chalcopyrite, 
not  resolvable  into  its  constituents  except 
under  a  high  power,  the  average  value  of 
which  lies  between  17  and  21%  copper.  Im- 
bedded in  it,  like  shot,  are  small  crystals 
of  pyrite,  which  apparently  crystallized  first 
from  the  'solid  solution'  of  the  mixture.  The 
observed  variations  in  the  value  of  the  '  pri- 
mary ores '  of  different  orebodies  can  thus  be 
explained  on  the  supposition  that  they  depend 
upon  the  relative  proportions  of  crystals  of 
pyrite  and  of  residual  or  interstitial  solid 
solution  of  pyrite  in  chalcopyrite  composing 
the  aggregate.  The  generally  greater  hard- 
ness of  the  poorer  ores  may  also  be  due  to  the 
same  cause. 

Besides  the  original  copper  contents  of  the 
primary  ore,  however,  two  entirely  different 
kinds  of  secondary  enrichment  are  to  be 
noted.  The  first  has  been  generally  recog- 
nized, because  most  obvious.  It  consists  in 
the  deposition  in  those  portions  of  the  ore- 
bodies  that  are  nearest  to  the  present  surface, 
and  in  the  forms  of  chalcocite  and  chalcopy- 
rite, of  a  large  part  of  the  copper  contents  of 
the  overlying  portions  of  the  orebodies  that 
have  been  removed  by  denudation  ;  and  in  the 
subsequent  alteration  of  the  chalcopyrite 
so  deposited  as  well  as  of  that  originally 
existing  in  the  ore,  to  chalcocite.  This  pro- 
cess has  taken  place  almost  invariably  in  all 
kinds  of  copper  sulphide  ore  deposits,  and  is 
that  commonly  known  as  'secondary'  or  per- 
haps more  properly  as  '  surface  enrichment.' 
Besides  this,  however,  there  appears  to  have 
been  another  kind  of  enrichment  of  these 
pyritic  masses  :  this  is  secondary  in  the  sense 
of  taking  place  subsequently  to  the  formation 
of  the  ore,  but  has  nothing  to  do  with  surface 
agencies  and  may  therefore  be  called  '  deep 
enrichment.'  It  is  due  to  the  introduction 
into  the  pyrite  of  chalcopyrite,  which  takes 
the  form  of  myriads  of  irregular  interlacing 
strings  from  styoth  up  to  an  inch  or  more  in 
thickness,  swelling  into  bunches  here  and 
there,  and  of  isolated  patches  that  may  run 
up  to  several  pounds  in  weight  of  almost  pure 
chalcopyrite. 

Entrance  of  this  secondary  chalcopyrite  has 
been  facilitated  by  the  crushing  and  Assuring 
ofthepyritic  massesbyrepeated complex  earth 
movements  subsequent  to  their  formation,  in 
some  cases  producing  a  brecciated  structure, 
readily  visible  in  parts  where  there  has  been 
also  considerable  infiltration  of  secondary 
quartz. 

The    secondary    chalcopyrite   is   generally 


associated  with  quartz,  sometimes  however 
with  calcite  or  dolomite,  large  numbers  of 
veinlets  of  which  are  seen  in  places,  occa- 
sionally running  up  to  3  or  4  inches  thick. 
More  rarely  barite  and  gypsum  are  found  as- 
sociated with  the  chalcopyrite. 

In  almost  all  the  pyritic  masses,  even  those 
the  average  copper  content  of  which  is  lowest, 
a  small  proportion  of  rich  chalcopyrite  ore  is 
picked  out  for  separate  treatment  or  ship- 
ment, and  this  holds  good  even  in  the  case  of 
lodes  like  that  of  Perrunal,  the  average  amount 
of  copper  in  which  is  so  low  that  the  vast 
bulk  of  the  ore  is  sold  for  its  sulphur  value 
only.  In  similar  fashion  to  the  chalcopyrite, 
bunches  and  veinlets  of  tetrahedrite  are  found 
in  some  of  the  masses,  and  this  also  is  often 
picked  out  for  separate  shipment  to  smelting 
works,  since  it  is  apt  to  be  rich  in  silver, 
assays  occasionally  running  as  high  as  2%  of 
silver  or  over  600  oz.  per  ton. 

The  close  association  of  the  'deep'  chalcopy- 
rite enrichment  with  calcite  and  dolomite,  as 
well  as  quartz,  coupled  with  the  fact  that  these 
minerals  are  often  found  in  greatest  abund- 
ance in  systems  of  veinlets  running  trans- 
versely to  the  strike  of  the  pyritic  masses, 
and  with  the  further  fact  that  the  ore-masses 
in  which  this  chalcopyrite  enrichment  is  most 
prominent  are  those  that  are  in  close  associa- 
tion with,  or  in  the  immediate  neighbourhood 
of  the  dikes  already  mentioned  as  running 
approximately  parallel  to  the  stratification 
of  the  country  and  to  the  lodes,  indicates 
in  my  opinion  that  the  secondary  chalcopy- 
rite is  probably  coeval  with  the  last  great 
series  of  tectonic  movements  in  this  region, 
namely  that  which  gave  rise  to  the  intrusion 
of  the  later  series  of  basic  dikes,  these  being 
certainly  of  post-Triassic  and  most  probably 
of  Tertiary  age.  Upon  this  theory  the  source 
of  the  copper  forming  this  deep  secondary 
enrichment  is  to  be  found  in  the  same  deep- 
seated  source  that  furnished  the  copper  in 
the  primary  ore ;  only  that  at  the  much  later 
date  of  this  secondary  mineralization  the  pre- 
ponderance of  iron  pyrite  had  disappeared, 
and  the  ascending  solutions,  which  were  prob- 
ably highly  alkahne,  now  brought  only  chal- 
copyrite, blende,  galena,  and  quartz,  with  a 
comparatively  small  proportion  of  pyrite. 
The  old  channels  or  vents  that  served  for  the 
production  of  the  pyritic  masses  having  been 
to  a  considerable  extent  sealed  from  below, 
the  solutions  came  up  in  some  cases  along 
one  of  the  walls,  in  others  through  new  lines 
of  weakness  or  fault-planes  forming  quartz- 
chalcopyrite  lodes,  like  the  Ratera,  near  \'al- 


124 


THE    MINING    MAGAZINE 


verde,  and  those  of  the  Campo  Frio  series, 
and  in  still  other  cases  with  the  basic  later 
eruptive  intrusions    themselves,   from   which 
their  mineral  contents  were  distributed  into 
the  crushed  and  fissured  pyrite,  forming  the 
series    of    interlacing    strings   with    compact 
bunches  of  chalcopyrite,  which  are,  although 
unevenly,   so    widely   distributed   throughout 
the  pyritic  masses.     When  the  ore  near  one 
wall  of  a  pyrites  lode  is  richer  in  copper  than 
that  near  the  other  wall,  it  is  almost  invari- 
ably the  case  that  the  rich  side  is  that  nearest 
the  eruptive   dike.      This  association  of  en- 
riched  portions   of  the   lode   with   proximity 
to   eruptives   is    well    exemplified    at    Cueva 
de    la    Mora,    San    Platon,  Esperanza,    and 
various  other  mines.      In    this  connection  it 
may  be  remarked  that  besides  chalcopyrite, 
native  copper  has  been  found  finely  dissemi- 
nated throughout  compact  diorite  on  the  foot- 
wall  side  of   a  small  pyrite   lode,  and  60  ft. 
away    from    it.       There    is    in    this    case  no 
evidence  of  transverse  jointing  such  as  could 
have    explained   transference  of   the  copper 
from  the  lode-channel  into  the  diorite,  and  it 
is  my  belief  that  the  copper  (which  is  evenly 
disseminated  through  a  considerable  extent 
of  the  diorite  as  shown  by  cross-cuts  60  ft. 
apart,  and  in  such  proportion  that  the  whole 
rock  assays  about  0'6%  copper)  is  an  original 
constituent  of  the  intrusive   rock,  and   it  is 
from  the  latter  that  '  deep  secondary  enrich- 
ment '  of  the  pyrite  has  been  effected. 

Besides  blende  and  galena,  already  men- 
tioned as  occurring  with  the  primary  ore,  and 
tetrahedrite  which  is  probably,  and  bornite 
certainly,  of  secondary  origin,  other  compara- 
tively rare  minerals  are  occasionally  found. 
Bournonite,  smaltite  and  native  bismuth,  for 
instance,  have  been  found  in  the  compara- 
tively small  but  exceptionally  rich  Monte 
Romero  lode,  all  however  in  cross-joints,  so 
that  they  are  probably  of  secondary  origin. 
Smaltite  has  also  been  found  on  the  hanging 
wall  of  the  Cueva  de  la  Mora  lode,  in  a  small 
veinlet  parallel  to  the  main  mass.  In  the 
zone  of  secondary  enrichment,  besides  chal- 
cocite  and  native  copper,  the  latter  in  masses 
up  to  5  lb-  weight,  fine  specimens  of  cuprite, 
malachite  and  azurite  are  occasionally  found, 
and  in  one  case  a  16-ton  lot  of  mixed  carbonate 
ores  was  shipped  by  me  from  a  pocket  just 
under  the  outcrop  of  a  small  pyritic  lode,  that 
contained  26%  copper,  wholly  as  carbonate  and 
oxide,  with  barely  a  trace  of  sulphur. 

In  the  zone  of  secondary  enrichment,  be- 
sides melanterite  and  chalcanthite  (the  for- 
mer often  containing  up  to  9  or  10%  copper). 


other  sulphates  are  sometimes  found,  includ- 
ing epscmite,  roemerite  (found  by  me  at 
Sotiel),  bloedite,  and  recently  at  the  Concep- 
cion  mine  a  most  interesting  group  of  asso- 
ciated sulphates,  including  copiapite,  coquim- 
bite,  roemerite,  and  at  least  two  other  species 
as  yet  undetermined. 

The  following  is  a  complete  list,  so  far  as 
known  to  me,  of  the  mineral  species  un- 
doubtedly found  up  to  date  in  Spanish  pyritic 
masses,  without  taking  into  account  alteration 
products  of  enclosed  or  associated  wall-rock 
such  as  sericite,  talc,  and  so  forth. 

Deep-seated  Zone  Surface-enrichment  Zone 

Pyrite  Native  Copper 

Chalcopyrite  Native  Silver 

Chalcocite  Native  Sulphur 

Blende  Claudetite 

Galena  Covellite 

Tetrahedrite  Cuprite 

Bournonite  Malachite 

Smaltite  Azurite 

Native  Bismuth  Brochantite 

Pyrrhotite  Bornite 

Magnetite  Erythrite 

Vivianite  Cerussite 

Quartz  Anglesite 

Calcite  Limonite 

Dolomite  Hematite 

Barite  Chalcanthite 

Gypsum  Melanterite 

Bloedite 
Epsomite 
Coquimb'te 
Copiapite 
Roemerite 
besides  two  other 
undetermined 
sulphates 

It  will  be  understood  that  in  the  zone  of 
surface  enrichment  are  found  the  minerals  of 
the  deep-seated  zone  in  addition  to  those  above- 
mentioned  as  peculiar  to  the  former  zone. 
Chalcocite,  although  commonest  in  the  zone 
of  surface  enrichment,  has  been  placed  among 
the  minerals  of  the  deep-seated  zone  because 
occasionally  found  at  considerable  depths, 
where,  however,  like  the  chalcopyrite  itself, 
it  has  been  obviously  introduced  after  the 
formation  of  the  pyrites  masses. 


Calumet  &  Hecla. — This  company  has 
made  a  new  departure  by  issuing  details  of 
production  and  cost.  During  1910,2,795,514 
tons  of  ore  was  treated,  yielding  72,059,545  lb. 
of  copper.  The  cost  per  pound  was  8'96c.  and 
the  average  price  obtained  13'2c. 


THE   FINANCE  OF  A   MINE.     Ill 

By  M.  H.  BURNHAM. 


AS  mentioned  before,  the  geographical 
position  of  most  mining  enterprises  with 
reference  to  centres  of  capital  tends  to 
thrust  a  special  duty  upon  the  engineer  ;  hence 
the  summation  of  the  individual  factors  influ- 
encing the  vending  interests  and  terms  of  pay- 
ment should  normally  fall  to  him  if  purchase 
be  regarded  from  an  economic  point  of  view. 
From  time  immemorial  sale  and  purchase  have 
implied  that  the  first  price  asked  is  based  on 
the  expectation  of  a  counter  offer,  and  subse- 
quent reduction,  while  the  very  nature  of 
economics  calls  for  an  effort  at  diminution  of 
risk,  often  best  accomplished  through  defer- 
ring cash  payments  by  means  of  shares  or 
debentures. 

Now,  one  may  frankly  ask  the  engineering 
world  how  completely  has  its  training  either 
at  school  or  in  ordinary  practice  equipped  it 
for  meeting  this  demand  upon  it  ;  how  many 
have  kept  sight  of  even  the  economics  of  in- 
dustry in  the  maze  of  purely  technical  advance ; 
and  still  again,  how  many  have,  though  keep- 
ing the  bases  of  industry  before  them,  acquired 
the  gentle  art  of  playing  speculation  as  a  sweet 
flageolet  wherewith  to  win  reluctant  vendors 
to  reason  ?  And  yet  these  are  modern  de- 
mands requiring  not  only  an  understanding  of 
the  economics  of  industry,  but  a  sound  grasp 
of  the  economics  of  finance  as  well. 

The  two  phases  of  development  represented 
financially  by  the  Syndicate  and  Company 
stages,  differ  principally,  in  that  the  former  is 
not  expected  to  have  ore  '  blocked  out '  and 
that  vendors  receive  only  shares  or  other  in- 
terest in  the  property,  while  the  latter  stage 
usually  implies,  in  sound  practice,  at  least, 
that  cash  outlay  on  purchase  and  plant  be 
represented  by  the  present  value  of  the  assured 
or  blocked  ore. 

In  the  ordmary  course  of  mining  operations 
the  successive  stages  may  be  roughly  sum- 
marized as  follows,  though  the  different  de- 
grees of  development  in  parts  of  a  developed 
mine  may  involve  problems  peculiar  to  an 
earlier  stage.     These  may  be  said  to  be: 

(1)  The  period  of  purely  geological  surmise  ; 

(2)  The  period   of   definite    quantities  and 

values,  as  well  as  of  surmise. 
If  I  may  be  allowed  to  recapitulate,  the  first 
article  of  this  series  dealt  with  the  fundamen- 
tal bases  of  valuation,  namely,  that  the  greater 


the  risk,  the  greater  the  rate  of  interest  re- 
quired. The  second  article  elaborated  the  first 
and  sought  to  show  that  this  simple  business 
concept,  if  expanded,  not  only  offers  a  solution 
of  the  problem  of  valuing  blocks  of  ore  in  dif- 
ferent stages  of  development,  but  makes  a  re- 
serve of  the  ore  below  the  deepest  level,  at  the 
same  time  fixing  a  lower  limit  to  these  blocks  ; 
otherwise,  it  determines  the  shoot-extension. 

Finance,  at  least  such  phases  of  it  as  legiti- 
mately concern  the  engineer,  calls  for  a  care- 
ful consideration  of  the  above  stages,  and  of 
the  first — that  of  geological  surmise — we  may 
say  without  nmch  fear  of  contradiction  :  '  Un- 
less profitable  ore  be  found  on  the  surface, 
sound  valuation  does  not  permit  of  cash  ex- 
penditure save  on  exploratory  work.'  Mani- 
festly this  implies  the  belief  that  the  orebodies 
will  repay  the  outlay  necessary  not  only  to  ex- 
ploration, but  to  development  and  plant  where- 
with to  realize  the  values  contained  ;  in  other 
words,  even  the  stage  of  geological  surmise 
implies  a  postulate  of  dimension  and  value. 
The  first  stage  is  more  especially  noticeable 
when  dealing  with  copper  outcrops,  where  pro- 
fitable ore  is  rare  at  the  surface. 

On  the  other  hand,  the  second  article  indi- 
cates that  in  the  case  of,  say,  a  gold  prospect 
stripped  along  the  outcrop  and  sampled,  one 
may  be  justified  in  paying  the  vendors  in  cash, 
the  amount  of  which  (see  Formula  X)  would 
depend  upon  the  profit  per  ton,  length  and 
thickness  of  shoot,  and  capacity  of  plant,  the 
value  of  which  must  be  redeemed,  and  other 
factors. 

It  follows  then  that  payment  for  property 
is  not  a  question  of  development  but  of  data 
available,  and  it  is  conceivable  that  a  well- 
sampled  outcrop  with  favourable  geological 
conditions  may  be  given  the  same  value  as  the 
deepest  level  in  a  mine. 

IF  IT  BE  ADMITTED  THAT  EXPENDITURE  ON 
GEOLOGICAL  SURMISE,  UNSUPPORTED  BY  ASSAY- 
VALUES,  OTHER  THAN  THAT  ON  EXPLORATION,  HE 
UNSOUND,  THEN  A  PLlRCHASE  INVOL\lNG  PAY^^iNT 
FOR  ORE  BELOvV  THAT  ALLOWABLE  AS  DETER- 
MINED BY  THE  ASSAY-VALUES,  IS   ALSO  UNSOUND. 

Stripped  of  technicality,  one  may  say  that 
where  outlay  is  made  independent  of  values, 
the  investors  are  '  backing  '  the  geologist's  sur- 
mise, and  while  they  might  cheerfully  support 
a  specialist  of  the  first  rank,  it  is  doubtful  if 
they  themselves  would  counsel  or  permit  pay- 
ment to  vendors  before  ore  was  found.     I-'ur- 


125 


126 


THE     MINING     MAGAZINE 


thermore,  all  of  these  men  would  have  at  least 
some  idea  of  the  economic  magnitude  of  the 
orebody  expected,  whether  it  be  a  '  saddle  '  at 
Bendigo  or  a  zone  of  secondary  enrichment 
below  a  brecciated  gozzan. 

If  the  foregoing  be  accepted,  then  the  ex- 
penditure on  exploration  per  unit  of  orebody 
expected  should  be  a  measure  in  current  prac- 
tice. As  it  would  seem  to  be  impracticable 
to  predict  the  depth  allowable  unsampled 
or  '  surmised '  ore,  the  unit  used  will  be  the 
sovereigns  of  profit  in  a  horizontal  slice  through 

the  ore-shoot,  one  foot  in  depth.  This  is  a 
basic  feature  common  to  both  stages  and  will 
be  called  the  '  economic  shoot '  ;'•'  it  serves  as 
an  index  and  means  of  classifying  the  possi- 
bilities of  each  and  should  be  clear  from  the 
following  figure,  which  reproduces  a  common 
type  of  undeveloped  prospect,  having  in  gene- 
ral an  appearance  in  plan  like  that  shown  in 
{a)  of  Fig.  4  ;  {b)  gives  a  longitudinal  section 
of  the  same  when  developed  to,  say,  the  Com- 
pany stage. 

It  would  seem  that  the  most  casual  specu- 
lative thought  would  go  a  step  beyond  the 
idea  conveyed  by  the  ordinary  word  '  shoot,' 
insomuch  as  the  boundaries  are  necessarily 
economic.  The  childish  drivel  of  concise  ter- 
minology prevalent  among  those  who  pass  for 
learned,  or  pose  as  practical,  is  especially  ex- 
asperating when  ore -shoots  are  being  con- 
sidered, and  one  wonders  that  mining  engi- 
neers are  allowed  even  the  degree  of  tolera- 
tion accorded  them  by  intelligent  financiers. 
What  the  latter  require  is  a  practical  founda- 
tion upon  which  to  base  their  calculations : 
some  sound  standard  whereby  to  compare  the 
probable  magnitude  of  the  enterprise  with 
others  of  similar  nature,  even  if  no  certainty 
exist. 

Surely  the  most  obdurate  must  admit  that 
a  term,  which  in  its  very  essence  is  economic, 
yet  which  conveys  no  definite  meaning,  sug- 
gests either  stupidity  or  intention  to  mislead. 
Surely,  when  a  '  shoot  '  may  be,  say,  1500  ft. 
long,  and  yet  be  either  6  inches  or  60  feet 
thick,  when  it  may  yield  6  pence  or  60  sover- 
eigns per  ton  in  profit,  the  use  of  mere  shoot- 
length  as  a  measure  of  magnitude  is  ineffec- 
tive, to  say  the  least.  What  our  more  reput- 
able financial  friends  demand  is  the  economic 
shoot,  which  for  each  foot  worked  along  the 
major  axis  yields  not  so  much  ore  but  so  much 
profit :  an  economic  slice,  as  it  were,  one  foot 
in  depth.     The  financier  would  then  be  in  a 

^  While  any  '  shoot  '  in  a  mine  is  essentially  determined  by 
'economic'  conditions,  this  use  of  the  term  expresses  magni- 
tude of  profit  as  distinct  from  physical  dimensions. 


position  to  compare  those  offered  by  different 
projects ;  to  gauge  probable  future  magni- 
tudes and  accordingly  shape  the  business  pro- 
gramme. 

This  estimated  dimension  of  the  economic 
shoot  applies  not  only  to  the  prospect,  but  to 
the  developed  mine  ;  it  is  often  as  applicable 
to  iron  as  to  gold  ;  to  china  clay  as  to  copper  ; 
to  a  bed  of  banket  as  to  the  channel  of  an 
ancient  river ;  whether  the  extension  be  hori- 
zontal, vertical,  or  incfined. 

The  one  point  of  difference  to  be  made  be- 
tween prospects  and  mines,  between  the  Syn- 
dicate and  Company  stages,  is  that  the  latter 
usually  calls  for  definite  assets  or  '  blocked 
ore,'  and,  if  well  financed,  the  economic  shoot 
with  its  possibilities  thrown  in. 

Prospects  may  be  conveniently  divided  into 
two  types,  depending  as  in  all  such  classifica- 
tion upon  the  validity  of  the  data  offered. 
These  are : 

(a)  The  geological  surmise  type,  as,  for  in- 

stance, petroleum  prospects  in   new 
fields ; 

(b)  Proved   shoot    type ;    with    ore    to    be 

sampled  on  one  side  only  as,  for  in- 
stance, an  ancient  working  in   Rho- 
desia accessible  to   sampling ;    or  a 
well  exposed  outcrop. 
In  the  case  of  (a)  it  may  be  stated  that  only 
upon   rare  occasions  could   it   be  considered 
sound  practice  to  lay  out  capital  save  for  de- 
velopment work,  while,  as  before  mentioned 
in  dealing  with   (6),  if  local  geological  data 
were  favourable  a  payment  to  vendors  might 
be   made   in  accordance   with   the   principles 
enunciated  in  the  preceding  article. 

From  the  foregoing  it  will  appear  that  fin- 
ance during  both  the  Syndicate  and  Company 
stages  is  vitally  concerned  with  the  magnitude 
of  the  economic  shoot,  while  the  ratio  of  that 
portion  of  the  paid-up  capital  of  the  company 
not  represented  by  the  present  value  of  the 
proved  ore,  to  the  units  in  the  economic  shoot, 
furnishes  a  means  of  comparing  valuations. 

It  will  have  been  noted  that  '  probability  ' 
as  a  term  defining  orebodies  has  been  elimin- 
ated, it  having  been  incorporated  in  the  risk- 
rate  principle.  There  remains,  however,  pos- 
sibility,' which  refers  to  the  economic  shoot 
below  the  ore  allowed  for.  For  example  : 
when  considering  two  mines  of  different  econo- 
mic-shoot proportions,  the  possibilities  of  se- 
curing the  always  hoped-for  bonanza  in  the 
ground  beyond  that  for  which  payment  may 
be  made,  might  be  said  to  be  greater  with  the 
bigger  economic  shoot,  as  a  single  foot  in 
depth  would  yield  a  greater  profit  in  the  case 


AUGUST,    1911 


127 


of  the  bigger  shoot.     For  instance  :  in  Fig.  4,      not  be  necessary,  it  is  as  well  perhaps  to  state 
though  we  may  pay  for^  the  ore  to  the  point      that  practically  the  whole  of  the  discussion 


c  d,  the  ore  beyond  is  '  possible  '  only.  In 
other  words,  we  pay  for  probability  but  hope 
for  possibility,  and  one  measure  of  financial 
ability  is  the  price  paid  for  a  unit  of  this  com- 
forting sensation,  as  discussed  later. 


Praf/V-  Feel^ 


ye  in 


MSM 


re^n 


^^^m 


SuftF/icE    CF  P/fospjs cr 


Fig  ^a  (  Sync//ca/-e  S/a^e) 


CP/anl 


of  economics  and  the  risk-rate  principle  has 
been  with  a  view  to  establishing  a  standard 
not  for  what  may  be  but  what  should  be  in- 
vested in  a  property.  That  is,  the  engineer 
too  often  neglects  the  human  element,  while 
the  financier  is  governed  by  it. 
Fconomic    Shoal-  The  tendency  of  the  former  is 

r^L^^^^^^^^,^iFcon0mt'c         to  base  his  offer  upon  the  value 
ya/aefeef  ^^>^r^  .^X^       SAoo^  of  the  property,  while  the  f^n- 

f^^^^^^  /"'     ancier's    consideration   is 
^L__\  ^^^      the  monetary  needs  of  the  ven- 

dor. This  illustrates  the  dif- 
ference in  psychology  between 
the  financier  and  engineer,  be- 
tween negotiation  and  valua- 
tion ;  between  human  nature 
and  formula. 

Evidently,  while  the  measure 
of  the  reporting  engineer  per  se 
is  his  ability  comprehensively 
to  express  technical  facts  and 
postulates  in  economic  units, 
that  of  the  financier  is  his  prac- 
tice with  reference  to  outlay, 
which  should  be  made  in  such  a 
manner  as  to  incur  the  least  risk 
or  to  invest  the  least  capital  in- 
cidental to  securing  a  given 
profit. 

Where  the  total  present  value 
is  paid  to  the  vendors  of  a  mine, 
it  may  be  safely  said  that  either 
the  mine  was  over-valued  by 
the  engineer,  or  the  financiers 
neglected  the  very  elements  of 
their  work,  which  are  intelli- 
gent negotiation  and  construc- 
tion after  valuation.  It  must 
be  confessed  that  even  the  de- 
gree of  self-appreciation  com- 
mon amongst  engineers  cannot 
obscure  the  fact  that  a  little 
deft  manipulation  of  the  per- 
sonal    factors     governing 


/fr<^.  e-f-^-/)-/-  e     =    Gross  ya/ue  Shoot 
"     ^-^-^  f        =        Economic    Shoot 

F/a  4  5.  f Company  5/^age )   lonry/^ud/na/  Sect/or 

For  the  purposes  of  illustration  cost-losses  and  shoot-thickness  are  taken  as  uniform. 


the    vending    interests 


The  foregoing  may  be  said  to  bear  particu- 
larly upon  what  is  permissible,  and  while  ideas 
will  vary  somewhat  both  as  to  the  risk-rate 
applicable  and  as  to  the  dimensions  of  the 
standard  block,  once  these  are  determined 
there  would  seem  to  be  small  room  for  great 
variations  of  opinion  as  to  what  constitutes 
sound  valuation. 

It  is  hoped  that  due  weight  has  been  given 
to  the  word  '  permissible,'  for  though  it  should 


will  often  secure  conditions 
that  make  ordinary  technical  economies  seem 
paltry ;  this  is  too  often  entirely  over- 
looked. As  before  mentioned,  an  opinion  as 
to  the  value  of  shares,  large  blocks  of  which 
are  often  offered  for  underwriting,  is  a  con- 
stant demand  and  while  the  basement  com- 
plex of  personality  which  aftects  the  market 
and  division  of  profits  from  such  sources  of 
profit,  concern  the  financier  only,  the  econ- 
omics of  the  enterprise  as  well  as  the  training. 


128 


THE    MINING    MAGAZINE 


experience,  and  good  name  of  the  engineers 
upon  whose  recommendation  flotations  are 
made,  concern  the  consulting  engineer.  The 
latter  has  then  to  consider  carefully  not  only 
the  company  construction  and  its  significance, 
the  technical  reports  and  data,  but  the  re- 
puted ethical  standards  and  responsibility  of 
the  valuing  engineer. 

From  the  foregoing  it  follows  that  not  only 
the  relation  of  the  proved  orebodies  to  the 
purchase  price  plus  equipment  outlay  must 
be  considered,  but  also  the  payment  made  for 
the  possibility  of  the  economic  shoot,  though 
the  latter  can  only  be  ascertained  by  combin- 
ing a  study  of  company  construction  and 
technical  reports. 


mentioned.  In  some  cases  costs  and  losses 
have  not  been  given  in  the  official  statements 
and  these  have  been  approximated,  as,  for  ex- 
ample, in  the  case  of  the  Prestea. 

While  Table  IV  seeks  to  show  the  signifi- 
cance of  the  magnitude  of  the  economic  shoot 
as  a  measure  of  finance,  a  later  article  will 
deal  with  the  relative  promise  of  great  and 
small  mines.  Columns  3,  4,  and  5  are  the 
proved  shoot-lengths,  mean  thicknesses,  and 
profit  per  ton  as  given  in  published  plans  or 
statements  only,  that  is,  they  are  not  private 
estimates.  Column  6  is  the  keynote  of  the 
Table,  and,  as  before  explained,  is  the  mea- 
sure of  the  ordinary  mine,  apart  from  the  re- 
serves,  being  the   profit  in  sovereigns  to  be 


Table  III.— The  Economic  Shoot. 


Mine. 


Pilares 
(Mexico) 

Mount  Morgan 
(Queensland) 

Santa  Gertrudis 
(Mexico) 

Mother  Lode 

(British  Columbia) 

Camp  Bird 
(Colorado) 


Metal 


Length  of  j    Average 
Shoot'  width* 


Gross 
value+ 
per  ton 


Ft. 


Ft. 


Mean  sec- 
tional 
value- 
feet  *  + 


Copper  I  1700    600  ,   8T0 


4860 


Combina-         ^j^^^ 
tion  factor      sectional 


Sovereign 
shoot-feetj 


6T        1200     i  27,000 


Gold-     j     800 
Copper 

Silver       1500 


Gold 
Gold 


1200 


1700 


500         1370      6850     ,      8'87      2330 


25,000 


15-5         23'20  :     360         lO'S  193         4,000 


150  670  i   1012 


4         3r50 


26 


57     !     150         2,500 


15"4 


64 


1,500 


*  .\pproximations,  for  illustration  only.  +  Values  in  U.S.  dollars. 

1 15  cubic  feet  per  ton  (approximate). 


Table  III  gives  a  list  of  five  well  known 
companies  with  the  approximate  magnitude 
of  their  economic  shoot  expressed  in  sovereign- 
feet. 

The  different  kind  of  shares  commonly  is- 
sued will  be  discussed  in  detail  in  a  later  ar- 
ticle, but  Table  IV  may  serve  to  emphasize 
the  significance  of  the  economic  shoot  as  ex- 
pressed in  terms  of  company-capital  and  mar- 
ket-value. The  present  value  of  the  reserves, 
that  is,  the  deferrence  factor,  is  neglected  for 
simplicity's  sake,  and  round  numbers  only  are 
given. 

To  those  interested  in  the  economics  of 
finance.  Table  IV  should  be  of  interest,  though 
through  lack  of  the  latest  facts  the  figures 
given  must  not  be  read  as  being  exact,  the 
idea  being  illustration  from  current  practice, 
and    not    information    concerning   the    mines 


expected  from  each  foot  in  depth  as  the  proved 
ore-shoots  are  exhausted.  It  is  held  that  this 
is  a  far  more  comprehensive  measure  of  the 
probable  futuremagnitudethan  the  ore  blocked 
out,  as  a  small  shoot  may  have  been  worked 
systematically  and  show  large  reserves,  while 
a  large  one  of  equal  profit  per  ton  may  have 
no  reserves  above  the  lowest  level.  In  this 
figure  of  economic  shoot  are  condensed  the 
work  and  innumerable  technical  calculations 
incidental  to  sampling,  assaying,  losses,  costs 
of  transport,  taxes,  duties,  refining  charges, 
and  a  host  of  others,  the  enumeration  of  which 
obscures,  often  designedly,  the  real  issue, 
which  is  the  estimated  future  magnitude  of 
the  mine.  Evidently  costs  and  losses  bear  a 
relation  to  capital  outlay  on  plant,  hence  such 
estimates  are  also  incorporated  in  the  econ- 
omic shoot.     The  last  word  is  used  advisedly. 


AUGUST,    1911 


29 


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130 


THE    MINING    MAGAZINE 


for  though  the  boundaries  of  any  shoot  are 
essentially  variables  as  determined  by  costs 
and  losses,  hence  economic,  the  ordinary  idea 
of  shoot  magnitude  as  expressed  by  area 
(length  and  thickness)  does  not  express  the 
profit  per  ton  ;  hence  is  entirely  misleading. 
As  the  shoot  bears  on  the  future  of  the 
mine  and  not  on  the  proved  reserves,  the 
lowest  full-shoot  level  is  where  one  looks  for 
data,  and  while  the  economic  shoot  at  one 
level  will  vary  from  point  to  point,  it  remains 
an  approximate  measure  of  what  one  may  ex- 
pect in  depth,  assuming  no  vitiating  geological 
features  like  the  danger  zone  so  common  at 
about  the  same  level  in  some  silver  camps 
where  zinc  ores  begin  to  appear.  Occasion- 
ally, of  course,  an  expanding  or  contracting 
rake  of  shoot,  as  indicated  by  assay-plans, 
might  be  considered,  but  usually  this  would 
be  considered  when  dealing  with  reserves  ly- 
ing below  the  deepest  level. 

Column  7,  giving  the  net  value  of  the  re- 
serves, calls  for  little  comment  beyond  sug- 
gesting that  the  validity  of  the  estimates  de- 
pends so  much  upon  the  size  of  the  blocks 
and  methods  of  sampling  and  appraisal,  that 
one  must  take  those  of  Table  IV  as  they  stand. 
In  reality,  their  actual  value  is  inadequately 
expressed  by  the  above  hgures,  inasmuch  as 
only  their  present  values  should  be  considered, 
by  allowing  interest  at  a  rate  commensurate 
with  the  risk  incidental  to  each  until  they  may 
be  realized  upon.  For  the  purpose,  however, 
of  comparing  the  '  finance  of  possibilities,'  the 
above  figures  will  answer. 

According  to  my  own  theorem  and  formulas, 
as  set  out  in  the  first  two  articles,  the  reserve 
should  include  ore  below  the  deepest  level  to 
a  certain  point  to  be  determined  by  simple 
calculation.  As,  however,  only  those  familiar 
with  the  local  geology  may  say  if  such  an  es- 
timate be  permissible,  those  reserves  lying 
above  the  lowest  level  are  alone  considered 
in  the  Table. 

Column  7  is  of  great  importance  as  express- 
ing definitely  the  valuation  (when  shares  are 
issued  at  par)  of  the  mine  as  estimated  by  the 
financiers  and  to  which,  it  is  contended  by 
me,  the  engineer  is  sponsor  and  participant, 
more  particularly  with  regard  to  the  first  flo- 
tation. This  figure,  coupled  with  the  kind  of 
shares  issued  (deferred,  debentures,  ordinary, 
etc.)  is  not  only  a  measure  of  the  engineer, 
moral  and  technical,  but  frequently  a  sure 
guide,  if  full  detail  be  published,  to  the  busi- 
ness acumen,  or  the  reverse,  of  the  financiers 
responsible. 

Column  9,  or  the  ratio  of  the  capital  of  the 


company  to  the  number  of  sovereigns  of  profit 
to  be  expected  from  exhausting  the  shoots  to 
a  depth  of  one  foot,  may  be  said  to  be  the 
payment  made  per  unit  of  possibility  and  is 
essentially  the  measure  of  mining  finance. 
To  some  it  will  be  more  convenient  to  regard 
it  as  the  number  of  feet  to  which  the  shoots 
must  be  exhausted  in  order  to  repay  the 
capital  of  the  company  (neglecting  interest). 
This  is  another  way  of  saying  that  those  re- 
sponsible for  the  flotation  predict  that  the 
mine  will  not  be  exhausted  before  a  certain 
depth  is  reached,  for  no  one  can  conceive  of 
risking  money  without  believing  that  he  will 
at  least  have  his  capital  returned.  In  plain 
English,  then,  capitalization  beyond  that  re- 
presented by  the  present  value  of  the  reserves, 
is  equivalent  to  an  estimate  of  shoot-extension 
in  depth,  whether  this  be  on  the  engineer's 
advice  or  not.  In  comparing  new  flotations, 
then,  if  no  ore  may  be  classed  as  a  reserve, 
this  ratio  (Column  9)  is  the  key  to  the  econ- 
omic position,  of  course,  in  default  of  modify- 
ing geological  data. 

Column  10,  or  the  issued  capital  (at  par) 
less  the  reserves,  is  of  particular  interest  only 
at  the  time  of  flotation,  for  the  capital  less 
the  net  value  of  the  reserves  must  represent 
the  amount  paid  for  the  estimated  possibilities 
of  the  mine. 

Column  11,  the  rate  paid  per  shoot-foot  or 
the  depth  to  which  the  shoots  must  be  ex- 
hausted in  order  to  repay  the  nominal  issued 
capital  less  reserves,  is  also  significant  only  at 
the  time  of  flotation.  For  example:  those 
responsible  for  the  Santa  Gertrudis  flotation 
practically  state  that  the  mine  warrants  a 
payment  for  shoot-extension  to  a  depth  of  not 
less  than  194  feet,  while  the  financing  of  the 
Redjang  Lebong  called  for  17  ft.  only.  One 
would  read  it  that  the  engineers  and  financiers 
of  the  Redjang  Lebong  must  have  looked  to 
dividends  and  an  appreciation  of  their  shares 
through  development  of  the  mine,  rather  than 
ask  subscribers  to  gamble  that  the  unproved 
ore  would  extend  to  any  depth. 

Columns  12,  13,  and  14,  or  the  market 
selling-price  of  the  mine,  is  affected  by  too 
many  factors  other  than  dividends,  to  bear 
upon  those  economics  of  finance  with  which 
alone  we  are  dealing.  On  the  other  hand, 
Column  14  is  extremely  interesting  as  illus- 
trating what  may  be  called  the  finesse  of  fin- 
ance as  distinguished  from  economics.  This 
subject,  however,  calls  for  a  subtlety  of  mind 
possessed  but  rarely  by  engineers,  and  could 
be  adequately  elucidated  by  only  two  or  three 
notable  exceptions  to  the  rule. 


AUGUST,    1911 


131 


In  the  interests  of  legitimate  mining  one 
cannot  do  less  than  call  attention  to  the  sound 
and  honourable  valuation  which,  as  indicated 
by  the  Table,  would  seem  to  be  the  policy  of 
those  directing  the  Redjang  Lebong,  the  Al- 
aska Mexican  and  the  Alaska  United.  Those 
connected  with  the  St.  John  del  Rey  company 
also  appear  to  be  governed  by  the  same  stan- 
dards. These  cases  are  of  great  interest, 
theoretically,  and  encouraging  to  those  who 
follow  mining  for  mining's  sake,  or  who  are 
concerned  with  the  economics  of  finance. 

Recapitulating,  we  may  say  as  a  premise 
that: 

(r)   Cash   expended   on  an   unproved   un- 
sampled  prospect  other  than  that  inci- 
dental to  exploration  is  unsound,  and 
(s)  The  cost  of  exploration  divided  by  the 
number  of  economic-shoot-feet  expec- 
ted is  a  measure  of  outlay  on  possibili- 
ties ; 
(/)   Ore  in  a  developed  mine  lying  below 
that  which  tlie  engineer  is  willing  to 
class  as  a  reserve  ('"')  and  pay  for,  is 
possible  '  only,  hence  is  of  the  same 
nature     as     the    unsampled    prospect. 
Therefore  outlay    other  than    for  ex- 
ploration is  also  unsound  ; 
(m)  The  issued  capital  of  a  company  (at 
par)  less  the  value  of  the  reserves  di- 
vided by  the  number  of  units  in  the 
economic  shoot,  is  the  outlay  made  per 
unit  of  possibility  and  is  a  measure  of 
finance  valuation. 
The  last   is  equivalent   to  the  number  of 
feet  in  depth  necessary  to  exhaust  the  mine 
in  order  to  repay  the  capital,  hence  a  very 
fair  idea,  in  default  of  modifying  geological 
data,  of   the  relative   promise  of   capitalized 
mines  may  be  had  by  applying  the  above  {ii) ; 
that  r,  s,  t  are  not  academic  postulates  finding 
no  expression  in  current  practice  is  shown  by 
reference  to  Column  1 1   where  it  is  seen  that 
the  capitalization  of  the  above  mentioned  three 
great  properties  has  not  allowed  for  more  than 
20  ft.  of  shoot-extension. 

*The  above  table  classes  as  reserves  only  the  ore  lying  above 
the  deepest  level.  I  hold  that  in  many  of  the  mines  cited,  an  al- 
lowance should  be  made  for  ore  below,  as  discussed  in  my 
second  article- 


Coal  in  South  Africa. — In  his  address 
to  the  South  African  Institute  of  Engineers, 
R.  N.  Kotze,  Government  Inspector,  spoke  of 
the  future  importance  of  the  coal  resources  of 
South  Africa,  and  gave  it  as  his  opinion  that 
the  proved  deposits  contained  20,000  million 
tons  of  available  coal. 


Kildonan  Goldfield. 

Paragraphs  have  been  published  in  the  Press 
recently  to  the  effect  that  a  returned  Klondiker 
is  making  an  examination  of  the  gravel  de- 
posits in  the  Helmsdale  and  tributary  valleys 
on  the  east  coast  of  the  county  of  Sutherland, 
in  Scotland.  Some  notes  on  this  goldfield  ex- 
tracted from  Malcolm  Maclaren's  volume  on 
'  Gold  '  will  be  of  interest.  Tradition  has  it 
that  gold  was  discovered  as  early  as  the  year 
1245,  but  no  authentic  record  is  extant  of  any 
work  being  done.  In  1840,  it  is  stated,  a  nug- 
get weighing  \\  oz.  was  found  in  the  Kildonan 
stream.  A  rush  was  made  to  the  district  in 
1868  and  for  a  year  or  so  quite  400  men  were 
occupied.  During  this  time  a  production  of 
gold  worth  ^3000  was  reported  officially,  but 
as  the  law  imposed  a  10%  royalty  there  is  good 
reason  to  believe  that  the  production  was  really 
much  greater.  A  competent  authority  put  the 
actual  figures  at  /^l  2,000.  At  about  the  same 
time  gold-bearing  gravel  was  found  about  ten 
miles  to  the  southwest  in  two  streams  that  run 
into  Loch  Brora;  the  work  however  interfered 
so  much  with  sheep-farming  that  the  licenses 
were  suspended  in  1870. 

The  Kildonan  district  consists  of  moorland 
and  heather-clad  hills,  with  extensive  bogs  at 
the  sources  of  the  streams.  The  valleys  are 
mostly  narrow  and  straight,  so  that  there  are 
few  alluvial  flats  of  any  notable  size.  The 
rocks  are  granites  and  metamorphic  schists  of 
varying  character,  and  over  them  are  thick 
deposits  of  glacial  drift  which  are  overlain  in 
turn  by  peat.  The  gold  is  found  as  small 
grains  in  the  beds  of  the  streams  and  in  the 
gravel  banks.  It  is  most  abundant  in  the 
coarse  gravel  and  in  the  crevices  of  the  up- 
turned edges  of  the  schist,  across  the  strike  of 
which  the  streams  run,  but  it  appears  to  be 
also  disseminated  throughout  the  drift.  The 
heaviest  nugget  ever  found  weighed  2  oz.  1 7 
dwt.  The  richest  deposits  so  far  known  were 
in  Gold  burn,  where  several  specks  may  still 
be  obtained  from  every  pan.  The  source  of 
the  gold  has  not  been  identified ;  it  is  doubt- 
less to  be  sought  in  the  quartz  veins  that  are 
found  in  the  schist  and  in  the  granite  at  the 
contact  with  the  schist.  Several  such  veins 
are  known,  but  apparently  no  indication  of  the 
presence  of  gold  has  been  recorded. 

Other  parts  of  Scotland  have  yielded  more 
gold  than  Kildonan.  For  instance,  during  the 
16th  century  extensive  alluvial  deposits  were 
worked  in  the  Leadhills  district  situated  in 
the  south  of  Lanarkshire.  The  original 
matrix  was  the  quartz  veins,  several  of  which 
have  been  proved  to  be  auriferous. 


MINING   IN   RHODESIA 

By  F.  P.  MENNELL. 


IN  endeavouring,  at  the  editor's  request,  to 
give  the  readers  of  The  Mining  Magazine 
some  idea  of  the  present  proportions  and 
future  prospects  of  the  Rhodesian  mining  in- 
dustry, I  am  confronted  by  a  very  real  diffi- 
culty. Rhodesia  is  not  a  country  of  one 
district,  one  mine,  or  even  one  metal.  Gold 
ranks  easily  first  in  importance  at  present,  but 
other  mineral  products  are  gradually  rising  in- 
to prominence  as  the  country  becomes  opened 
up  and  the  cost  of  working  is  reduced.  Even 
if  attention  be  confined  to  gold,  it  is  impossible 

t  to  be  struck  with  the  widely  scattered  situ- 
ations of  the  principal  mines.  There  is  no 
'  gold-belt '  (to  use  the  prevalent  local  term) 
that  greatly  outshines  its  fellows  in  impor- 
tance ;  indeed,  it  is  rare  for  a  big  productive 
mine  to  have  many  near  neighbours  of  much 
promise.  Whether  the  comparative  isolation 
of  the  larger  orebodies  tends  to  the  advantage 
of  the  industry,  or  otherwise,  it  is  hard  to  say, 
but  it  is  certain  that  it  has  led  to  a  more  general 
exploitation  of  the  territory  than  would  be  the 
case  if  the  futureof  Rhodesian  mining  depended 
on  a  Rand  or  a  Kalgoorlie.  What  is,  however, 
more  to  the  point  is  that  this  fact  renders  it 
difficult  to  summarize  the  industry  in  the  course 
of  a  brief  article.  In  keeping  with  their  wide- 
spread geographical  distribution,  the  mines  of 
Rhodesia  vary  extremely  in  geological  occur- 
rence and  mineralogical  characteristics,  while 
their  mining  methods  and  metallurgical  prac- 
tice exhibit  equal  diversity,  having  borrowed 
much,  sometimes  from  one  centre,  and  some- 
times from  another,  though  not  without  the 
addition  of  features  peculiarly  their  own. 

Southern  Rhodesia,  the  territory  to  which 
alone  the  name  Rhodesia  '  is  popularly  ap- 
plied, is  not  a  definite  geological  unit :  its  rocks 
extend  into  the  surrounding  territories  in  all 
directions.  Yet  even  the  northern  Transvaal, 
with  its  large  areas  of  precisely  similar  crystal- 
line schists,  invaded  in  the  same  way  by  huge 
granitic  intrusions,  is  apparently  inferior  from 
a  mining  standpoint,  a  fact  which  seems  ano- 
malous in  view  of  the  widespread  distribution 
of  the  auriferous  and  other  lodes  of  Southern 
Rhodesia  itself.  The  Rhodesian  '  gold-belt  ' 
rocks,  moreover,  strongly  resemble  the  Kolar 
schists  in  India,  as  well  as  those  of  the  meta- 
morphic  areas  of  Western  Australia.  That 
they  are  of  Archaean   age  can    scarcely    be 


doubted ;  indeed  in  the  granitic  gneisses  with 
which  they  are  so  closely  associated  it  is  pos- 
sible to  recognize  theequivalent  of  the  Lauren- 
tian  system  of  Canada,  which  have  been  shown 
by  Adams,  as  I  have  endeavoured  to  demon- 
strate in  Rhodesia,  to  be  intrusive  in  the  cry- 
stalline schist  which  was  at  one  time  supposed 
to  overlie  them  in  true  stratigraphic  sequence. 
The  granite  here  is  not  predominantly  gneissic 
in  structure,  but  there  is  no  real  reason  for  con- 
sidering that  there  is  any  definite  distinction 
in  age  between  the  different  types, especially  as 
they  frequently  grade  into  each  other.  The  in- 
vaded formations  comprise  (l)  Massive  epidio- 
rites,  together  with  more  typical  hornblende 
and  chlorite  schists,  (2)  a  series  characterized 
by  the  peculiar  laminated  ferruginous  rock 
known  as  banded  ironstone,'  often  associated 
with  basic  igneous  intrusions,  especially  ser- 
pentine, (3)  a  series  of  grits  and  conglom- 
erates with  intercalated  amygdaloids  ;  to 
which  may  be  added  in  some  localities  a  suc- 
cession of  limestones.  The  details  of  the  re- 
lationships of  these  rocks  must  await  the  re- 
searches of  the  geological  survey  recently  in- 
stituted under  the  direction  of  Mr.  H.  B. 
Maufe ;  for  a  general  account  of  them  the 
reader  may  be  referred  to  my  paper  in  the 
Quarterly  Journal  of  the  Geological  Society  for 
August  of  last  year.  All  these  ancient  rocks 
occupy  with  the  granites  the  higher  parts  of 
the  country  near  the  Zambesi- Limpopo  water- 
shed, and  it  is  in  them  that  nearly  all  the  gold 
veins  and  other  mineral  lodes  are  found. 

Quartz  Reefs. — As  in  most  other  coun- 
tries, veins  of  quartz  constitute  the  main  source 
of  the  gold.  They  are  most  common  among 
the  hornblendic  rocks  and  gradually  conform 
to  the  strike  of  the  enclosing  country.  They 
are  nevertheless  often  true  '  fissure  veins  '  oc- 
curring along  planes  of  faulting,  and  may  cut 
across  the  strike  of  the  schist.  The  length  of 
the  orebodies  is  usually  not  great,  yet  in  their 
continuity  they  are  more  satisfactory  than  in 
the  persistence  of  their  gold  contents.  A  length 
of  500  ft.  along  the  strike  is  exceptional  for  a 
profitable  ore-shoot,  but  among  the  larger 
mines  the  maximum  extent  is  as  much  as 
4500  ft.,  as  the  Surprise.  The  Phoenix  shoot 
averaged  750  ft.  in  length  before  the  present 
rich  ore  was  struck.  Since  then  the  pay-ore 
has  extended  for  over  1000  ft.     At  the  Lonely 


132 


AUGUST,    1911 


133 


mine  the  length  of  ore  is  also  just  about  1000  feature  of  being  close  to  granite  contacts,  and 

ft.  The  average  width  isratherunder  30  inches  there  can  be  little  doubt  that  the  intrusion  of 

at  the  Globe  &  Phoenix  and  about  3  ft.  at  the  the  granite  was  a  determining  factor  in  the  for- 

Lonely.     Of   course,   there   are   much   wider  mation  of  a  large  proportion  of  the  orebodies. 

veins,  such  as  the  Jessie  at  Gwanda  and  the  This  is  a  much  more  striking  characteristic 

Bell  at  Sebakwe,  but  they  are  much  lower  in  than  the  association  with  basic  rocks,  on  which 

grade  than  the  33  dwt.  ore  of  the  Phoenix  or  authorities  like   Ur.  Maclaren  have  strongly 


RHODESIA. 


the  20dwt.  of  the  Lonely.  It  is  a  characteristic 
of  these  and  most  other  veins  in  Rhodesia  that 
in  the  pay-shoot  the  big  widths  nearly  always 
coincide  with  the  richest  ore.  Instances,  how- 
ever, can  be  cited  where  the  ex.act  reverse  is 
the  case,  as  in  the  Tuff-nutt  at  Bembezi. 

The  country  rock  shows  great  diversity  of 
character.  It  is  noticeable  nevertheless  that 
most  of  the  leading  mines  have  the  common 


insisted.  The  following  list  may  be  found  in- 
structive : 

In  Epidiorite  country  :  Beatrice,  Bucks, 
Farvic,  Joker,  Queens. 

In  Serpentine  or  its  alteration  products  : 
Eiffel-Blue,    Eileen-Alannah,    Lonely,    Pen- 

halonga. 

In  Hornblende-Granulite  :  Blanket,  Jessie, 

Mont  d'Or. 


134 


THE    MINING    MAGAZINE 


In  Mica  Granulite  or  Gneiss  :  Etna,  Fal- 
con, Ophir,  Surprise,  Valley. 

At  or  very  close  to  granite  contacts  :  Asp, 
Bonsor,  CoUeen-Bawn,  Don,  Geelong,  Globe 
&  Phcenix,  Morven,  Tebekwe. 

In  Hornblende  or  Chlorite  schist :  Clare- 
mont.  Criterion,  Nelly,  Northern  Star,  Sabi. 

In  Grit :  Abercorn,  Bell,  Durban. 

In  Banded  Ironstone  :  Bristol,  Champion, 
Susannah,  Ubigubi. 

In  most  cases  the  lode-matter  is  fairly  clean 
quartz  with  only  a  little  finely  disseminated 
pyrite,  and  occasionally  galena  or  other  sul- 
phide as  well.  There  are,  however,  some  in- 
teresting exceptions.  Thus,  in  the  Bell  mine, 
which  has  a  vein  probably  averaging  10  ft. 
wide,  the  west  end  of  the  orebody  is  quartz, 
but  the  eastern  portion  is  a  soft  chloritic  aggre- 
gate, often  containing  masses  of  crystalline 
dolomite,  with  included  fragments  of  country. 
The  Blanket,  Mont  d'Or,  and  Jessie  '  reefs,' 
as  is  nearly  always  the  case  in  granulite  coun- 
try, are  characterized  by  the  presence  of 
splashes  of  pyrrhotite  ;  in  the  last  case  ac- 
companied by  galena  where  the  ore  is  richest. 
The  Penhalonga  contains  crocoisite  (lead  chro- 
mate)  near  the  surface  and  galena  lower  down, 
both  these  minerals  being  rich  in  silver.  The 
Falcon  and  Valley  lodes  are  heavily  charged 
with  sulphides,  including  pyrrhotite,  iron  pyrite, 
and  copper  pyrite.  The  latter  has  yielded  con- 
siderable quantities  of  copper  as  a  by-product 
and  the  former  is  expected  to  doso  in  the  future. 
The  Yankee  Doodle  (Selukwe  Columbia  Gold 
Mining  Co.)  and  Bongola-Sheba  reefs  at  Se- 
lukwe may  be  mentioned  as  sulphide  lodes  of 
quite  a  different  type,  rich  in  galena,  pyrite 
and  blende.  They  present,  it  may  be  men- 
tioned, no  treatment  difficulties  that  cannot  be 
overcome  by  fine  grinding,  though  at  one  time 
considered  highly  refractory.  The  Champion 
at  Gwanda  contains  much  mispickel,  altered 
near  the  surface  into  scorodite. 

Impregnation  Deposits. — We  may  now 
turn  to  the  type  of  lode  that  has  sprung  into 
great  prominence  during  the  past  few  years, 
that  in  which  the  gold  occurs  impregnating  a 
rock  mass  instead  of  being  confined  to  a  quartz 
vein.  As  an  illustration  of  the  importance  of 
these  lodes  it  may  be  noted  that  of  the  three 
largest  producers  and  dividend-payers,  two, 
the  Eldorado  and  the  Giant,  are  impregnation 
deposits,  while  all  of  the  three  largest  develop- 
ing mines  belong  to  the  same  category.  The 
Eldorado  is  in  conglomerate  or  '  banket  '  and 
the  Giant  in  a  wide  shattered  mass  of  banded 
ironstone  associated  with  talc  and  chlorite 
schists.     The  big   Shamva  orebody  at  Aber- 


corn, on  which  a  large  plant  is  shortly  to  be 
erected,  is  in  conglomerate  and  grit  of  a  differ- 
ent lithological  type  from  the  Eldorado,  but 
also  of  a  highly  metamorphic  character.  The 
banded  ironstones  contain  a  number  of  impor- 
tant impregnations,  usually  low  m  grade  but 
of  considerable  width,  though  the  Antelope 
mine  provides  an  example  of  good  grade,  and 
widths  no  greater  than  many  quartz  veins.  It 
is,  however,  in  immediate  contact  with  the 
granite.  The  Ayrshire,  a  mine  once  so  pro- 
minent, is  an  instance  of  gold  occurring  in  a 
granulite  or  gneiss  at  a  granite  contact.  It  is 
popularly  termed  a  diorite,  but  is  undoubtedly 
of  contact  metamorphic  origin.  In  serpentine 
we  have  important  deposits  at  the  Gaika  and 
the  Cam  &  Motor  mines,  while  the  Arcturus- 
Slate  group  at  Enterprise  is  in  a  peculiar 
variety  of  schist  characterized  by  the  presence 
of  a  green  chrome-bearing  mica.  The  follow- 
ing is  a  list : 

In  Banded-Ironstone  :  .\ntelope,  Conces-. 
sion,Connemara,  etc.  (at  Hunter's  Road),  Em- 
press (Victoria  district).  Giant,  Golden  Kopje, 
New  Found  Out,  Redrup's  Kop,Sabiwa,  Wan- 
derer &  Camperdown. 

In  Mica,  Hornblende  or  Chlorite  Schist  : 
Arcturus, Slate, 6cc.(Enterprisedistrict),  Bush- 
tick,  Planet,  Rouge. 

In  Altered  Serpentine  :  Blue  Duck,  Cam 
&  Motor,  Gaika,  Robin  Hood. 

In  Granulite,  &c.  :  .Vyrshire,  Common- 
wealth, Jumbo,  Hay,  St.  Davids. 

Development  of  the  Industry. — The 
presence  of  most  of  the  above  lodes,  whether 
of  quartz  or  otherwise,  was  revealed  to  the 
modern  prospector  by  ancient  workings,  which 
had  served  usually  to  exhaust  the  bulk  of  the 
oxidized  ore.  There  are  no  alluvial  deposits 
worthy  of  mention,  no  doubt  largely  owing  to 
the  tropical  character  of  the  rainfall,  and  this, 
with  the  depletion  of  the  surface-enriched  lode 
stuff  by  the  ancients,  has  prevented  either  big 
nuggets  or  sensational  pockets  from  attracting 
a  population  of  the  same  class  as  flooded  the 
Californian  and  Australian  diggings  of  the 
'fifties.  In  spite  of  this,  highly  exaggerated 
expectations  were  originally  entertained  of  the 
future  of  many  mines  that  afterward  proved 
incapable  of  supporting  even  the  smallest  mills. 
It  was  the  failure  to  justify  the  reckless  op- 
timism of  many  of  the  earlier  promoters  that 
led  to  Rhodesia  being  regarded  as  a  huge  dis- 
appointment, and  it  is  only  during  the  last  few 
years  that  developments  have  led  to  a  reversal 
of  this  judgment. 

The  recent  revival  of  confidence  is  due  in 
the  first  place  to  the  small  worker.   Under  the 


AUGUST,    1911 


135 


original  mining  law,  millingwas  only  permitted  Globe  &  Phoenix-  -and  many  even  of  the  resi- 

after  flotation  of  the  claims  into  a  limited  com-  dents  were  extremely   pessimistic   as  to   the 

pany  in  which  half  the  vendor  interest  had  to  future  of  the  industry.      In  a  few  years  the 

be  allotted  to  the  Chartered  Company.     This  outlook  had  entirely  changed,  and  by  the  be- 

'50%  clause'  is  undoubtedly  one  of  the  severest  pinning  of  1908  the  success  of  the  small  worker 


THE  ETNA  MINE. 


exactions  under  which  the  mining  industry  of 
any  country  has  ever  suffered  and  even  though 
it  was  speedily  reduced  to  30%  it  led  to  much 
over-capitalization,  if  nothing  worse.  There 
can  be  no  doubt  that  the  first  great  step  in  the 
direction  of  putting  the  industry  on  a  sound 
basis  was  made  when  the  visiting  directors  of 


had  not  only  put  fresh  faith  into  the  average 
Rhodesian,  but  had  begun  to  react  favourably 
on  the  position  of  the  larger  companies.  At 
present  we  are  not  through  the  transition  stage 
due  to  the  companies  entering  the  field  again 
as  purchasers  of  properties  opened  up  by  the 
small   workers.     A  few    mines,  such  as  the 


THE  ANTELOPE  MINE. 


the  Chartered  Company  in  1903  arranged  to 
permit  the  working  for  profit  (on  a  small  scale 
only)  of  gold  claims  in  return  for  a  royalty  on 
the  gross  output.  At  the  time  there  was  only 
one  dividend-paying  mine  in  the  country — the 


Lonely,  are  just  ready  to  undertake  production 
on  a  much  increased  scale,  but  an  even  greater 
number  have  ceased  milling  altogether  during 
the  progress  of  development  work,  and  will 
not  re-enter  the  productive  class  for  some  time. 


136 


THE    MINING    MAGAZINE 


The  result  of  this  state  of  affairs  is  that  the  in- 
dustry has  presented  to  outsiders  the  appear- 
ance of  practically  marking  time,  the  output 
having  been  nearly  stationary  for  three  years, 
as  the  following  figures  indicate  : 

Ounces  of  Gold.  Value. 

1908 606,961  ;^2,526,006 

1909 623,388         ;^2,623,708 

1910 609,955         ^2,568,198 

At  present  fully  one  third  of  the  total  labour 
force  is  employedonnon-producing  mines, and, 
as  a  result  of  the  development  in  hand,  a  num- 
ber of  large  mills  should  come  into  operation 
next  year  on  such  mines  as  the  Shamva,  the 
Cam  &  Motor,  the  Arcturus  &  Slate,  the 
Eileen-Alannah,  the  Antelope,  the  Kimberley, 
and  the  Sabi.  Other  smaller  properties  will 
help  and  several  large  low-grade  bodies  are 
also  likely  to  swell  the  production.  Without 
exaggerated  optimism  an  increase  in  the  total 
yield  of  at  least  ten  to  fifteen  thousand  ounces 
per  month  may  fairly  be  anticipated  in  the  im- 
mediate future.  The  maintenance  of  this  im- 
provement will  depend  entirely  on  the  number 
of  new  discoveries  made,  and  these  will  of 
necessity  be  virgin  veins,  as  the  possibilities 
offered  by  the  remaining  ancient  workings  are 
now  strictly  limited. 

Labour  Supply. — A  dominant  factor  in 
the  prospects  of  an  improved  output  is  that  of 
labour  supply.  The  progress  of  the  industry 
is  obviously  dependent  on  the  number  of 
natives  it  is  possible  to  recruit  as  labourers, 
and  there  is  a  constant  shortage  in  this  direc- 
tion. Matters  are  not,  however,  by  any  means 
so  bad  as  most  people  would  have  us  believe. 
The  amount  both  of  local  and  imported  labour 
has  shown  a  constant  tendency  to  increase  and 
the  recent  re-organization  of  the  Rhodesian 
Native  Labour  Bureau  promises  further  im- 
provement in  the  future.  Moreover,  there  is 
no  question  but  that  the  shortage  leads  to 
economy,  and  mine  managers  often  find  that 
their  working  costs  go  up  as  their  complement 
of  natives  approaches  the  number  of  boys  they 
reckon  they  ought  to  have.  Another  mine 
manager,  who  has  achieved  wonders  on  his 
own  mine,  attributes  much  of  his  success  to 
employing  relatively  large  numbers  of  white 
miners.  There  is,  he  considers,  a  tendency  to 
place  a  white  man  in  charge  of  more  natives 
than  he  can  really  look  after  properly,  and  this 
may  well  explain  the  decrease  of  efficiency 
above  noted  as  the  result  of  an  increased  sup- 
ply of  native  labour.  It  may  be  remarked 
that  hand-drilling  is  almost  universal  and  ma- 
chines are  only  used  on  a  few  of  the  '  big  ' 
mines.     With    regard    to    white    labour,    the 


supply  offers  few  difficulties,  as  immigration 
automatically  ensues  as  soon  as  vacancies  oc- 
cur on  the  different  mines  in  sufficient  number 
to  attract  outside  attention.  The  white  miner 
is,  of  course,  purely  an  overseer  of  the  boys  ' 
who  do  the  actual  work,  except  that  he  is 
generally  expected  to  do  the  blasting  of  the 
holes  that  have  been  drilled.  White  wages 
are  high,  as  might  be  anticipated  from  the  high 
cost  of  living.  The  following  are  typical  of  the 
ruling  rates  of  pay  per  shift  : 

Miner  20s.  to  22s.  6d. 

Amalgamator 21s. 

Cyanider 20s. 

Engine  Driver    20s.  to  22s.  6d. 

Carpenter    21s.  6d. 

Fitter  21s.  6d. 

Native  wages  vary  considerably,  according  to 
the  supply  in  different  localities  and  the  experi- 
ence of  the  boys.  Hammer- boys  earn  about 
30s.  to  50s.  per  month,  plus  food  and  quarters. 
Surface-boys  can  sometimes  be  got  for  as  little 
as  15s.  per  month. 

Water  and  Fuel. — The  important  ques- 
tions of  fuel  and  water  supply  may  be  briefly 
touched  upon.  In  a  country  with  tropical 
climatic  conditions,  that  is  to  say  with  per- 
fectly distinct  wet  and  dry  seasons,  each  ex- 
tending over  about  half  the  year,  water  often 
causes  trouble  by  its  overplus  at  one  period 
and  its  scarcity  at  the  other.  It  cannot  be 
said,  however,  that  Rhodesia  is  a  badly  watered 
country  and  there  are  on  the  other  hand  only 
a  few  spots  where  the  rainfall  is  really  exces- 
sive for  any  length  of  time.  The  general  aver- 
age for  the  whole  country  must  be  a  little  un- 
der 30  inches  per  annum,  of  which  the  bulk 
falls  from  November  to  February.  There  are 
certain  districts  where  surface  water  is  lacking, 
except  in  the  larger  streams,  during  the  greater 
part  of  the  dry  season,  and  some  of  these  are 
difficult  to  prospect  on  that  account.  There  is 
nevertheless  seldom  much  difficulty  in  obtain- 
ing a  good  supply  by  sinking  to  a  moderate 
depth,  say  about  60  ft.,  and  it  is  often  the  places 
where  least  exists  above  ground  that  yield  the 
most  below. 

Some  of  the  big  mines  have  to  pump  for 
considerable  distances  ;  thus  the  Globe  & 
Phoenix  pumps  7  miles,  the  Gaika  6,  the 
Shamva  2h,  and  so  on.  In  no  case,  however, 
can  it  be  said  that  any  important  deposits  lie 
idle  through  lack  of  water.  A  large  proportion 
of  the  smaller  properties  are  able  to  run  on 
what  is  pumped  from  their  own  workings  or 
from  pools  in  a  stream  close  at  hand. 

As  regards  fuel,  wood  is  in  general  use  and 


AUGUST,    1911 


137 


the  timber  of  the  country,  scrubby  as  it  is,  has 
proved  on  asset  of  much  value  from  this  point 
of  view.  Rhodesia  is  fortunate  in  the  posses- 
sion of  coalfields  of  considerable  extent,  and 
that  at  Wankie  produced  180,000  tons  of  coal 
in  1910.  It  so  happens,  however,  that  the  coal 
measures  are  always  distant  from  the  meta- 
morphic  backbone  of  the  country  on  which  the 
leading  gold  mines  are  situated,  and  this,  in 
the  existing  state  of  railway  communication, 
prevents  coal  being  so  generally  used  as  would 
otherwise  be  the  case,  especially  in  Mashona- 
land.  Suction-gas  plants  have  therefore  been 
utilized  on  a  number  of  properties,  and  appear 
to  have  proved  satisfactory.  There  can  be  no 
doubt  that  the  timber  of  the  country  has  led  to 


mcrease  in  the  farming  population  has  had  the 
effect  of  decreasing  the  prices  of  maize  and 
other  food-stuffs  as  supplied  by  the  mining  com- 
panies to  the  native  labourers  ;  hence  of  reduc- 
ing costs  in  this  direction  also.  The  mainten- 
ance of  large  clerical  and  other  staffs,  a  legacy 
from  the  Rand,  is  quite  unsuited  to  local  con- 
ditions, and  even  on  the  large  mines  it  is  now 
considered  unnecessary  to  have  more  than  two 
or  three  men  in  the  '  office.'  The  tributer  had 
great  influence  in  this  direction.  When  it  was 
found  that  he  could  secure  profits  on  5  or  6 
dwt.  ore,  the  London  boards,  which  had  hither- 
to been  content  to  accept  as  normal  costs 
reaching  £2  or  more  per  ton,  began  to  agitate 
for  similar  results  from  their  own  mines.      It 


A  small  Rhodesian  Mine. 

a  much  greater  extent  of  mining  operations 
than  could  possibly  have  happened  in  such  a 
bare  area  as  the  southern  Transvaal.  There 
the  treeless  veld  could  never  have  supported 
mines  unless  they  were  rich  enough  to  justify 
the  construction  of  a  railway  for  their  especial 
benefit  to  bring  coal  from  a  distance. 

Working  Cost.— The  Rhodesian  mining 
industry  is  now  in  a  healthy  condition  as  re- 
gards working  methods  evolved  from  experi- 
ence. In  the  early  days  extravagance  was  rife, 
though  legitimate  mining  was  costly  enough  in 
all  conscience  owing  to  the  great  distance  from 
the  railhead.  Now  the  railways  make  quite  a 
respectable  show  on  the  map — a  remarkable 
one,  indeed,  when  the  smallness  of  the  white 
population  is  considered.  The  condition  of 
the  wagon- roads  still  leaves  much  to  be  de- 
sired, but  steps  are  being  taken  to  remedy  this, 
an  important  matter  when  it  is  considered  that 
mines  like  the  Lonely,  Antelope,  and  Sabi  are 
from  50  to  70  miles  from  the  railway.  The 
2—5 


The  Eldorado  Mine. 

then  became  necessary  for  their  representa- 
tives in  Rhodesia  to  demand  greater  efficiency 
from  their  subordinates,  and  a  weeding-out 
process  ensued,  and  ranged  from  miners  up  to 
consulting  engineers.   Even  people  who  lacked 
real  experience  began  to  take  an  interest  in 
what  their  neighbours  were  doing  and  a  gradual 
reduction  of  costs  ensued.     At  present  about 
25s.  per  ton  may  be  considered  as  an  average 
for  mines  of  moderate  size  with  comparatively 
narrow  lodes.  Larger  bodies  are  worked  much 
cheaper,  and  the  Wanderer  has  been  able  to 
point  to  the  proud  record  of  7s.  per  ton,  treating 
its  ore  by  dry  crushing  and  direct  cyaniding. 
The  experience  gained  by  this  time  is  of  much 
value  to  responsible  engineers.  They  can  now 
come  to  a  rapid  decision  as  to  what   prospects' 
are  worthy  of  having  money  spent  on  their  de- 
velopment, and  far  more  can  thus  be  done  use- 
fully for  a  given  sum  of  money  than  was  pos- 
sible a  few  years  ago.     The  same  applies  to 
metallurgical  processes. 


138 


THE    MINING    MAGAZINE 


PERSONAL 

Arthur  R.  Andrew  has  returned  to  Lon- 
don from  Colombia. 

H.  Foster  Bain,  editor  of  the  Mining  & 
Scientific  Press,  was  recently  in  Alaska. 

Sydney  H.  Ball  has  returned  from  Brus- 
sels to  New  York. 

J.  M.  Bell,  on  his  return  from  Canada, 
left  for  Spassky  on  August  2. 

Louis  P.  Bowler,  the  author  of  '  Gold 
Coast  Palaver '  has  arrived  from  Secondee, 
West  Africa. 

R.  GiLMAN  Brown  is  back  from  Kyshtim. 

George  P.  Chaplin  is  in  British  Colum- 
bia on  behalf  of  Bruce  Marriott  &  Co. 

Edgar  A.  Collins,  formerly  of  Tonopah, 
Nevada,  is  now  assistant  manager  at  the  City 
Deep  on  the  Rand. 

W.  Cullen  has  returned  to  Johannesburg 
after  a  holiday  in  England. 

G.  A.  Denny  is  expected  shortly  from 
Mexico  City. 

R.  Farina  has  returned  from  the  Altai, 
Siberia. 

F.  C.  Frey  is  at  Lebong  Soelit,  in  Sumatra. 

C.  Hanckel  has  returned  from  Australia. 

Henry  Hay,  who  was  recently  married  in 
South  Africa,  returned  to  West  Africa  on 
August  10. 

C.  A.  Heussler  is  now  in  Labrador,  but 
he  expects  to  return  to  Newfoundland  before 
leaving  for  England  in  September. 

W.  A.  Heywood  is  in  Spain,  as  consulting 
metallurgist  to  the  Cordoba  Copper  Company. 

H.  Lancaster  Hobbs  has  returned  from 
Northern  Nigeria. 

Edwin  C.  Holden,  professor  of  mining 
in  the  Universityof  Winconsin,  passed  through 
London  on  his  way  to  Spain. 

E.  C.  HOMERSHAM,  the  manager  of  the 
Prestea  mine,  is  here  from  West  Africa. 

J.  Power  Hutchins  returned  from  the 
Ural  region  and  is  now  at  St.  Petersburg. 

J.  T.  Keating  has  been  appointed  manager 
for  the  Kano  (Nigeria)  Tin  Areas. 

Mark  R.  Lamb  has  returned  from  the  high- 
lands of  Bolivia  to  Santiago. 

Frank  Langford,  the  manager  for  the 
Braden  Copper  Co.,  is  in  London. 

Albert  R.  Ledoux  sailed  for  New  York 
on  July  29. 

C.  W.  Lee,  formerly  of  the  Geldenhuis 
Deep,  is  in  London,  on  his  way  to  Mexico. 


Thos.  H.  Leggett,  on  his  return  from 
Paris,  left  for  New  York  on  July  15. 

T.  M.  Lowry,  of  Camborne,  who  has  been 
for  three  years  Inspector  of  Mines  on  the  Gold 
Coast,  has  been  appointed  Inspector  in  North- 
ern Nigeria. 

George  Macfarlane  and  Bernard 
Hunt  returned  from  the  Gold  Coast  in  July. 

Edward  T.  McCarthy  is  at  Porcupine. 

J.  Morris,  lately  joint  general  manager  of 
the  East  Rand  Proprietary,  has  been  appointed 
manager  of  the  City  Deep  mine. 

Maurice  Percival,  manager  for  the  North- 
ern Nigeria  Mining  &  Exploration  Co.  is  ex- 
pected in  London. 

C.  R.  Pinder  is  returning  to  South  Africa. 

C.  W.  PURINGTON  has  left  St.  Petersburg 
on  his  way  to  Vladivostok. 

H.  M.  Ridge  is  at  Nelson,  British  Columbia. 

P.  A.  Robbins  is  manager  for  the  Hollinger 
Gold  Mines  at  Porcupine. 

William  Roberts  is  in  Egypt. 

Thomas  Robins  is  at  Antwerp. 

G.  W.  RuDYERD  has  gone  to  Northern 
Nigeria. 

George  Safford  was  married  on  July  25 
and  sailed  for  Ecuador  on  August  2. 

C.  B.  Saner  has  been  elected  president  of 
the  Chemical,  Metallurgical  &  Mining  Society 
of  South  Africa  for  the  ensuing  year. 

A.  L.  Simon  is  expected  in  London  on  his 
return  from  Siberia. 

Howard  D.  Smith  sailed  for  New  York 
on  July  19. 

G.  E.  Stephenson,  manager  for  the  Pal- 
marejo  &  Mexican  Gold  Fields  is  due  in  Lon- 
don shortly. 

J.W.H.Stubbs,  lateoftheRandfontein,but 
now  with  the  Albu  group,  left  London  for 
Johannesburg  on  August  5. 

U.  P.  Swinburne  has  arrived  from  South 
Africa. 

S.  C.  Thomson  sailed  for  South  Africa  on 
August  5. 

J.  B.  Tyrrell,  of  Toronto,  made  a  short 
visit  to  England,  leaving  on  August  11. 

S.  S.  Webb-Bowen  has  returned  from  the 
Celebes  Islands. 

H.  C.  Woolmer,  manager  of  the  Spassky 
mine,  has  returned  to  his  post. 

A.  Basil  Reece  has  resigned  his  appoint- 
ment in  Bolivia  and  will  return  to  England  in 
October. 


BALL-MILL  PRACTICE  AT  KALGOORLIE 

By  M.  W.  VON  BERNEWITZ. 


SO  much  has  been  written  about  the  stamp- 
mill  that  other  efficient  pulverizers  are 
apt  to  be  overlooked ;  so  I  make  no 
apologies  in  presenting  these  notes  on  the 
modern  ball-mill,  in  this  case  the  Krupp,  in 
the  hope  that  they  may  be  of  use  to  others 
who  have  a  plant  in  operation,  or  contemplate 
erecting  one.  It  is  doubtful  whether  the  ball- 
mill  is  operated  with  greater  efficiency  and 
less  cost  anywhere  in  the  world  than  at  Kal- 
goorlie,  that  is,  crushing  dry.  We  have  had 
great  experience  with  them,  and  with  a  con- 
stant interchange  of  ideas,  each  plant  is  well 
abreast  of  its  neighbour,  until  there  is  a  prac- 
tical uniformity  of  practice. 

The  ores  of  the  '  Golden  Mile,'  the  richest 
portion  of  the  goldfield,  do  not  vary  much  in 
composition,  and  taken  on  average,  it  may  be 
said  that  they  are  hard  to  crush.  The  ore 
averages  60%  silica.  In  the  Great  Boulder 
the  proportion  is  as  high  as  75%.  Below  are 
short  descriptions  of  the  eras  treated  in  the 
dry-crushing  plants: 

Associated Partly    schist,    rather 

above  average  in  sili- 
ca, hard,  and  highly 
mineralized. 

Associated  Northern... Main  lode  of  schistose 

character,  West  lode 
hard  and  silicious. 

Chaffers Varies  from  schistose 

to  hard  flinty  quartz, 
with  3  to    5%    pyrite. 

Great  Boulder Very    hard    cherty 

quartz  with  a  little 
schist. 

Kalgurli Quartz  diabase  vary- 
ing in  hardness  accord- 
ing  to  depth,  some 
schistose,  and  other 
highly  silicious.  Aver- 
age tough. 

Perseverance Schistose  in  structure, 

and  contains  pyrite  and 
magnetite  throughout. 

South  Kalgurli Average  60%  silica, 

with  little  schist,  and 
is  considered  hard. 

The  following  are  analyses  from  the  Asso- 
ciated Northern  and  Perseverance  mines  : 


% 

Insoluble 60'60 

Aluminium  oxide 575 

Iron  bisulphide 532 

Lime  carbonate iri9 

Magnesium  carbonate. . .     5'29 

Iron  carbonate 10'23 

Alkali  undetermined 1*62 


% 

63"46 
2"06 
6*80 

13'42 
6*93 
6"80 
0'53 


100"00       lOO'OO 


The  average  ore  is  dry  enough  for  milling, 
although  the  driest  holds  from  0'5  to  1%  mois- 
ture. Anything  above  this  amount  retards 
crushing.  As  in  a  stamp-battery,  or  other 
type  of  crushing  machine,  a  great  deal  of  the 
efficiency  depends  on  having  massive  founda- 
tions. So  it  is  with  the  ball-mill.  A  mill  on 
a  solid  block  of  concrete  will  crush  better  than 
one  on  a  timber  or  steel  girder,  no  matter  how 
well  braced.  A  springy  support  is  bad  for  the 
gear,  and  does  not  allow  the  mill  to  be  stiff, 
as  it  were.  This  has  been  noticed  especially 
in  the  Associated  plant  built  1 1  years  ago,  in 
which  10  mills  were  resting  on  timber  girders, 
and  two  on  concrete  piers,  the  latter  doing  far 
better  work  than  any  other  pair  in  the  plant. 
The  former  foundation  consisted  of  a  masonry 
bed,  on  which  stood  12  by  6  in.  steel  girders 
with  brackets  riveted  to  support  two  longti- 
tudinal  pieces  of  jarrah  (native  hardwood)  12 
by  14  in.  across  which  were  bolted  three  pieces 
of  12  by  14  in.,  for  each  mill.  This  would  ap- 
pear to  be  stiff  enough,  but  the  vibration  was 
bad  all  the  same.  Now  the  big  mills  are  on 
fine  concrete  foundations,  reinforced  with  old 
wire  rope  and  rails.  The  Associated  Nor- 
thern, Chaffers,  Great  Boulder,  and  Persever- 
ance ball-mills  are  erected  on  massive  con- 
crete foundations,  especially  the  last  men- 
tioned ;  those  at  the  Kalgurli  sit  on  steel  gir- 
ders 8  by  6  in.  well  braced  and  apparently 
firm  ;  while  in  the  South  Kalgurli  plant  they 
are  bolted  to  a  frame  of  12  by  12  in.  timbers, 
well  braced  and  standing  on  a  concrete  founda- 
tion. This  looks  a  small  structure,  but  it  is 
free  from  vibration. 

As  soon  as  the  foundations  are  sufiiciently 
set,  and  the  four  bearings  for  the  mill-shaft 
and  pulley-shaft  are  lined  up,  the  construction 
can  proceed  rapidly.  With  8  men  who  under- 
stand the  work,  a  mill  may  be  erected  in  24 


139 


140 


THE    MINING    MAGAZINE 


hours.  Everything  is  simple.  The  main  walls 
are  bolted  or  riveted  to  the  cast-iron  naves, 
which,  when  in  their  proper  places,  are  keyed 
to  the  mill-shaft.  The  side  liners  are  bolted 
loosely  until  all  the  mantle-plates  with  the 
grinding-plates  are  in  position,  then  every- 
thing may  be  tightened,  all  bolts  having  check- 
nuts,  except  those  on  the  mantles  holding  on 
the  grinding-plates,  which  are  riveted.  The 
fitting  of  the  scoops,  baffles,  inside  and  outside 
screens,  is  quite  a  simple  matter.  The  feed- 
hopper  is  in  two  pieces  for  bolting  around  the 
shaft,  and  is  lined  for  the  wear  of  ore  drop- 
ping from  the  feeder.  Unless  motor-driven, 
each  mill  has  a  fast  and  loose  pulley  on  the 
pinion  shaft.  There  are  two  sizes  of  mills  at 
work  in  Kalgoorlie,  with  the  following  dimen- 
sions : 

No.  5  No.  8 

Inches  Inches 

Diameter 89  106 

Width 46  54 

Mantles  for  plates 10  12 

Inside  screens 5  6 

Outside  screens 10  12 

Area  of  outside  screens, 

each 46by26     54  by  24 

The  last  item  is  the  full  area,  without  de- 
ducting that  part  of  the  screen  covered  by  the 
wooden  frame.  Approximately, the  net  screen- 
ing surface  on  each  mill  is  70  and  100  sq.  ft. 
respectively. 

The  mantles  carry  four  or  five  grinding, 
and  one  perforated,  plates,  which  are  tightly 
bolted  together.  The  bolts  have  a  feather  on 
the  tapered  portion  to  fit  into  the  plates,  thus 
preventing  turning  during  tightening.  Bolted 
to  the  bottom  end  of  the  mantles  are  the  baffle 
and  scoop  plates,  which  return  the  oversize  to 
the  mill.  The  whole  mill  is  enclosed  in  a 
tight-fitting  casing,  made  in  convenient  sec- 
tions for  removal  during  repairs.  The  spur- 
wheel,  keyed  to  the  mill-shaft,  is  usually  of 
cast-iron,  and  should  last,  if  well  greased, 
fully  four  years  ;  while  the  pinion  lasts  about 
half  that  time.  The  loose  pulley  runs  on  a 
sleeve  which  must  be  well  greased  to  prevent 
seizing.  On  one  of  the  new  mills  at  the  As- 
sociated, a  new  idea  for  loose  pulleys  has  been 
devised,  in  the  shape  of  a  cast-iron  bracket 
with  an  extended  hollow  sleeve,  bolted  to  the 
plummer-block  furthest  from  the  mill.  The 
pinion-shaft  revolves  in  this  sleeve,  and  the 
loose  pulley  rests  on  the  latter.  When  the 
mill  is  working,  the  pulley  is  at  rest,  thus  pre- 
venting much  wear  at  this  point. 

It  is  found  that  a  good  stiff  light  grease  is 
best  for  all  bearings  on  a  ball-mill.     A  few 


turns  of  a  grease -cup  twice  in  8  hours  is 
generally  sufficient.  For  the  gear,  old,  but 
clean,  grease  from  other  bearings  is  good 
enough.  Properly  fitted  gear,  when  well 
greased,  makes  little  noise. 

When  driven  off  a  main  driving-shaft,  tight 
and  loose  pulleys  are  required ;  but  when 
motor-driven,  the  former  only  is  necessary. 
The  Great  Boulder  people  are  fitting  clutch- 
pulleys  on  the  main  shaft  with  satisfactory 
results.  An  8  in.  6-ply  balata  or  rubber  belt 
is  strong  enough  for  a  No.  5  mill,  and  a  10  in. 
8-ply  for  a  No.  8. 

From  24  to  26  rpm.  is  the  correct  speed  for 
the  No.  5,  and  from  21  to  24  rpm.  for  the  No. 
8.  It  is  generally  admitted  that  the  latter 
speed  for  the  larger  mill  is  quite  safe  and 
shows  much  greater  efficiency,  although  the 
makers  stipulate  the  lower  speed.  Mills  are 
loaded  with  1  to  2  tons  of  5  in.  steel  balls  ac- 
cording to  size  and  hardness  of  the  ore  to  be 
crushed ;  there  is  no  advantage  in  feeding 
several  sizes  of  balls.  Indicator  diagrams  at 
the  Associated  Northern  and  Associated  have 
shown  that  the  No.  5  mill  takes  from  18  to  23 
hp.  when  in  an  average  working  condition,  and 
the  No.  8  consumes  50  to  60  hp.  Where  motor- 
driven,  as  at  the  Perseverance  and  South  Kal- 
gurli,  the  ammeters  register  60  to  65  amperes 
at  550  volts. 

It  is  found  advisable  to  have  the  storage 
bin  for  coarse  ore  a  few  feet  behind  the  ball- 
mills,  as  it  enables  a  proper  chute  with  a  gate 
and  a  long  feeder  to  be  attached,  thus  giving 
a  steady  flow  of  ore,  which  cannot  be  assured 
when  the  bin  is  right  over  the  mills,  as  origin- 
ally erected  at  the  Associated. 

For  the  protection  of  employees,  and  keep- 
ing the  plant  free  of  dust,  and  the  better  work- 
ing of  a  ball-mill,  a  strong  fan  attached  to  the 
mills  by  large  piping  is  necessary  ;  and  a  plant 
properly  arranged  in  this  detail  is  a  pleasure 
to  operate.  A  couple  of  Sturtevant  fans,  about 
4  ft.  diam.,  running  at  about  800  to  1000  rpm. 
should  keep  eight  No.  8  mills  clear;  and  a 
"3  ft.  fan,  as  we  have  it  at  the  Associated 
Northern,  running  at  800  rpm.  is  effective  for 
three  No.  5  mills.  A  4  ft.  motor-driven  fan 
at  the  Associated  takes  5  amperes.  Suction 
and  delivery  pipes  should  be  fitted  with  slid- 
ing doors  to  facilitate  cleaning.  The  draft  in 
the  suction-pipe  at  the  Associated  Northern 
averages  0'33  in.  The  fan  generally  blows 
the  dust  into  a  canvas-lined  house,  in  which 
it  readily  collects,  or  as  at  the  last-named  mill, 
it  is  blown  into  the  second  hearth  of  the  Mer- 
ton  furnaces.  At  the  Perseverance,  the  dust 
is  collected  in  cyclone  arresters,  and  then  into 


AUGUST,    1911 


141 


FOUR  No.  S  BALL-MILLS  AT  THE   GREAT  BOULDER  PERSEVERANCE. 


TWO  OF  THE  No.  5  BALL-MILLS  BELONGING   TO   THE  ASSOCIATED  NORTHERN. 


142 


THE    MINING    MAGAZINE 


the  main  furnace  flue.  A  strong  draft  aids  in 
keeping  screens  clear,  especially  when  the  ore 
is  at  all  damp,  the  steamy  air  being  with- 
drawn. When  dry  crushing  with  stamps  at 
Waihi  in  New  Zealand,  in  1894  to  1899,  the 
beneficial  effect  of  a  fan  was  very  noticeable. 
The  amount  of  dust  lost  in  dry  crushing  is 
difficult  to  estimate  ;  but  from  observations  I 
should  say  it  would  represent  1%  at  least. 

The  ball- mill  feeders  are  usually  of  the 
grasshopper  or  shaking  tray  type,  that  is,  a 
sloping  tray  with  sides  6  in.  high  at  an  angle 
of  about  25°,  suspended  at  the  discharge  end 
by  a  chain  or  rod  from  a  beam  above,  and  the 
top  end  supported  by  two  iron  legs,  fitted 
loosely  to  the  underside  of  the  tray,  and  to  a 
timber  support  near  the  floor.  At  the  back  of 
the  feeder-tray  is  a  tappet,  and  on  a  shaft  is  a 
single,  double,  or  three-armed  cam,  adjustable 
to  give  as  much  as  a  1  in.  lift  to  the  feeder. 
This  pushes  the  feeder  back,  which,  when  re- 
leased, drops  forward  by  its  own  weight,  dis- 
charging an  even  flow  of  ore  into  the  mill.  It 
is  the  custom  now  for  each  mill  to  have  its 
own  feed-shaft  driven  by  a  3  in.  belt  from  a 
pulley  fitted  to  an  extension  of  the  mill-axle. 
The  mills  at  the  Perseverance  are  so  fitted, 
the  whole  being  neat  and  effective.  At  the 
South  Kalgurli  the  feeders  are  arranged  with 
a  perforated  tray,  through  which  the  fine  ore 
passes  to  a  shaking  tray  fitted  with  27  by  27 
in.  screen,  this  in  turn  screening  all  that  por- 
tion already  fine  enough,  it  passing  to  the  con- 
veyor beneath.  We  tried  one  for  some  time 
at  the  Associated  Northern  but  did  not  think 
it  increased  the  capacity  of  the  mill.  The  ar- 
rangement requires  close  watching.  Naves 
are  arranged  for  left  and  right  hand  feeding, 
by  this  means  mills  may  be  run  in  pairs,  the 
hoppers  being  reasonably  close  together  ;  and 
it  may  be  remarked  here  that  mills  should  not 
be  too  close  together,  as  plenty  of  space  is 
required  for  repairs.  The  balls  are  fed  either 
through  the  manhole  door  or  hopper,  and  ore 
is  added  until  the  balls  are  well  mixed  with  it. 
A  mill  should  not  be  started  without  ore,  as 
the  balls  knock  the  plates  about  badly.  Un- 
less a  mill  is  motor-driven,  it  would  be  diffi- 
cult to  arrange  for  an  automatic  feeder.  I 
have  not  heard  of  any,  but  think  that  one 
could  be  devised,  depending  on  the  increase 
of  power  consumed  above  a  set  point.  If  a 
mill  takes  60  amperes  with  a  full  load,  and  is 
overfed  to  62  amperes,  then  some  automatic 
gear  could  shut  off  the  feed.  Like  many  other 
machines  a  ball  -  mill  is  worked  by  sound. 
This  is  an  important  point  to  impress  on  mill- 
men,  as  a  poor  attendant  may  easily  cut  the 


efficiency  of  a  mill  by  25%,  in  not  keeping  his 
ears  open.  An  operator  becomes  keen  to  the 
exact  rumble  of  a  ball-mill,  and  can  detect  a 
light  feed  from  a  distance.  A  mill  running 
empty  simply  roars ;  when  light  there  is  a 
clear  metallic  sound  of  balls  striking  one  an- 
other ;  when  just  right,  there  is  simply  a  rumb- 
ling noise  ;  while  in  a  mill  that  is  full,  the  balls 
and  ore  are  carried  high  enough  to  fall  directly 
on  to  the  mill-axle  or  shaft,  this  being  bad 
work,  as  the  shaft  is  liable  to  be  damaged  and 
worn,  and,  of  course,  crushing  is  reduced  to  a 
minimum.  The  remedy  for  too  much  feed,  of 
course,  is  shutting  it  off  until  the  correct  sound 
is  noted.  A  millman  not  too  sure  about  his 
feeding  can  easily  see  this  by  stopping  the 
mill,  and  looking  into  it  through  the  feed-nave 
with  a  light.  The  mass  of  balls  and  ore  should 
be  evenly  distributed,  and  no  bare  balls  should 
be  showing. 

The  operation  of  the  Krupp  ball-mill  may 
be  described  as.  follows  :  The  mill  is  a  gear- 
driven  steel-lined  drum,  charged  with  1  to  2 
tons  of  steel  balls,  revolving  at  26  to  24  r. p.m. 
according  to  size.  The  ore  crushed  by  the 
balls  passes  through  the  perforated  grinding 
plates,  and  is  screened  by  the  inside  or  coarse 
screen,  the  oversize  being  returned  automati- 
cally to  the  interior  of  the  mill ;  while  what 
passes  the  inside  screen  is  sized  by  the  out- 
side or  fine  wire  screen,  the  oversize  being 
also  returned  to  the  mill  for  further  grinding. 
The  action  of  crushing  and  returning  the  over- 
size is  ingenious,  and  it  will  be  seer  that  as 
soon  as  the  ore  is  crushed  fine  enough,  it  must 
pass  out  of  the  mill.  Herein  lies  the  efficiency 
of  the  ball-mill.  In  a  5-stamp  battery  the  ore 
is  pulverized  excessively  by  not  being  dis- 
charged directly  it  is  fine  enough.  In  the 
ball-mill  there  is  little  of  this,  and  any  ma- 
chine that  discharges  its  product  immediately 
it  is  of  the  required  size  will  show  high  effi- 
ciency. As  regards  the  action  of  the  balls,  it 
has  been  stated  that  crushing  is  done  by  im- 
pact ;  but  from  careful  observation  I  am  per- 
fectly satisfied  that  this  is  not  so,  the  only 
impact  that  might  take  place  is  when  the  balls 
drop  from  one  grinding-plate  to  another,  a 
distance  of  five  inches  in  a  newly  lined  mill ; 
and  then,  only  some  fine  particles  would  be 
crushed  by  impact  at  this  point.  The  action 
of  the  balls  is  one  of  pure  rolling,  grinding, 
and  abrasion,  they  being  lifted  about  level 
with  the  mill-shaft  or  axle,  and  then  roll  back, 
tumbling  over  one  another,  rubbing  and  grind- 
ing the  ore.  Of  course,  there  is  a  great  deal 
of  attrition  between  the  pieces  of  ore  apart 
from  the  work  of  the  balls.     This  is  not  mere 


AUGUST,    1911 


143 


supposition,  as  I  have  actually  seen  the  action. 
At  the  Associated  mill,  we  had  four  No.  5 
mills  crushing  our  oxidized  ore  that  carries 
some  5%  moisture,  so  we  used  coarse  screens, 
in  fact  the  wire  screens  were  removed,  and  the 
inside  ones  used  only,  these  being  punched 
steel  with  30  holes  per  sq.  in.  In  crushing 
this  ore  no  dust  is  made,  so  by  the  aid  of  a 
portable  electric  lamp,  placed  well  down  in 
the  feed-hopper,  the  balls  and  ore  could  be 
seen  plainly.  It  was  observed  that  the  balls 
and  ore  were  carried  up  nearly  level  with  the 
shaft,  and  having  reached  this  point,  started 
to  roll  back.  The  1200  lb.  weight  of  steel 
was  rolling  and  tumbling  about,  grinding  and 
rubbing  the  ore  between  the  balls.  It  was  a 
most  interesting  sight,  fully  proving  that  there 


sharp  fracture  or  not,  with  the  result  that  they 
show  the  +30  screen  product  to  be  somewhat 
rounded,  and  the  +120  to  have  sharp,  ragged 
edges.  I  saw  the  particles  under  the  microscope, 
and  was  quite  satisfied  with  the  evidence. 

This  shows  that  the  final  particles  are  split 
by  the  rolling  of  heavy  balls,  not  necessarily 
by  the  drop  of  a  ball  as  in  a  tube-mill,  de- 
scribed by  H.  Fischer  in  several  of  the  lead- 
ing technical  journals  in  1904. 

Fig.  1  shows  how  perfectly  round  the  balls 
continue  in  wearing  from  full  size  to  the 
smallest,  and  the  smooth  round  pieces  of  ore 
and  steel.  Fig.  2  is  a  micro-photograph  of 
the  final  particles  from  a  ball-mill.  This  ex- 
cellent photograph  was  taken  by  G.  Larcombe, 
of  our  local  School  of  Mines. 


MICRO-PHOTOGEAPHS    OF  BALL-MILL   PRODUCTS. 


is  no  impact  grinding.  To  confirm  this,  one 
has  only  to  take  note  of  the  ore  in  a  mill  when 
it  is  stopped  for  repairs.  Down  to  the  small 
particles,  say  6  mesh,  it  is  smooth  and  round 
just  as  if  water-worn  from  a  river.  Pieces  of 
steel,  which  come  from  the  mine  at  times,  are 
rounded  in  the  mill,  although  they  hinder  good 
work.  If  impact  were  the  action  in  a  ball- 
mill,  dynamite,  which  also  finds  its  way  with 
the  ore,  would  explode  as  it  does  in  a  Griffin 
mill ;  but  it  does  not,  and  I  take  it  that  it  is 
just  rubbed  away.  F.  B.  Allen,  Director  of 
Technical  Education  in  this  State,  has  kindly 
examined  some  ball-mill  product,  which  was 
wet-screened  to  clean  the  particles  from  dust, 
under  the  microscope,  to  see  whether  it  had  a 


In  a  table  following  Table  I.  will  be  found 
the  consumption  of  steel  and  life  of  liners. 
Steel  consumption  is  gauged  by  the  weight  of 
balls  consumed  per  ton  crushed,  and  not  by 
the  total  balls  and  liners  used,  as  in  a  battery 
where  shoes  and  dies  are  calculated.  The 
average  steel  consumption  in  the  ball- null 
plants  here  is  0'55  lb.  per  ton,  while  the  hunch 
or  grinding- plates  last  about  190  days,  the 
perforated  as  long,  and  side  liners  about  twice 
as  long.  Manganese  steel  of  the  Hadfield  or 
Krupp  make  is  most  satisfactory.  As  regards 
capacity  we  may  say  that  the  efficiency  de- 
pends on  the  quantity  crushed  per  horse-power 
consumed.  A  No.  5  Krupp  mill  crushes  ordi- 
nary sulphide  ore  up  to  43  tons  daily,  and  the 


144 


THE    MIXING    MAGAZINE 


No.  8  up  to  100  tons,  and  dividing  this  by  the 
horse-power  consumed  (18  to  23,  and  60  to 
65)  we  get  2'1  and  1*6  tons  per  hp.  respec- 
tively. In  a  small  plant  of  100  tons  daily 
capacity,  the  No.  5  is  a  useful  unit,  but  in  a 
large  plant  the  No.  8  is  the  best  size.  This 
has  a  large  capacity,  runs  sweetly,  and  occu- 
pies little  more  space  than  the  smaller  unit. 
The  quantity  of  ore  crushed  as  given  above  is 
from  actual  weighings  in  some  cases,  and  from 
the  tonnage  crushed  divided  by  the  hours  run 
in  others.  On  quartz  the  capacity  of  a  No.  5 
mill  is  lower,  being  about  36  tons  per  diem. 
We  had  excellent  opportunities  of  finding  out 
the  capacity  at  the  Associated  Northern,  as  all 
the  custom  ore  is  weighed. 

It  is  impossible  to  prevent  damp  ore,  from 
1  to  3%  moisture,  coming  into  a  plant.  Then 
the  efficiency  decreases  greatly  and  the  wear 
and  tear  becomes  heavier,  as  the  feed  must  be 
light  to  prevent  screens  clogging,  a  steaming 
being  set  up,  that  makes  everything  sticky. 
When  crushing  dry  ore,  the  inside  of  the  mill 
becomes  hot  from  friction,  a  recent  test  show- 
ing up  to  130°  F.  when  the  outside  tempera- 
ture was  97°.  The  Kalgurli  used  to  dry  its 
damp  ore  before  milling,  but  rotary  dryers  are 
a  nuisance.  The  soft  oxidized  ore  can  best  be 
crushed,  as  at  the  Associated  and  Associated 
Northern,  by  only  using  about  1200  lb.  of 
balls,  taking  off  the  outside  screens,  and  pass- 
ing it  through  the  inside  or  coarse  screens. 
Pans  reduce  this  product  quite  easily.  Actual 
tests  show  that  a  No.  5  mill  will  crush  up  to 
82  tons  daily,  but  for  the  5%  moisture  the 
capacity  would  be  greater.  The  Chaffers  has 
one  mill  on  this  class  of  ere,  wet  crushing  93 
to  100  tons  through  26  by  26  screen  per  diem, 
using  2400  lb.  in  balls. 

It  is  advisable  to  open  mills  for  inspection 
once  a  week,  unless  something  goes  wrong  in 
the  meantime,  and  every  two  months  the  balls 
should  be  taken  out  and  weighed,  all  balls 
under  1^  in.  being  discarded,  as  they  are  of 
little  use  in  crushing,  and  the  original  weight 
made  with  new  balls  of  18  lb.  each.  Foreign 
matter,  such  as  drill-ends,  bolts,  nuts,  spanners, 
accumulate  in  mills,  and  as  they  hinder  the 
smooth  work  of  the  balls  they  must  be  thrown 
out. 

One  man  at  lis.  8d.  per  shift  of  8  hours  can 
look  after  eight  No.  8  mills  ;  but  in  smaller 
plants  the  millman  attends  to  conveyors,  ele- 
vators, dust-pipes,  etc.  Ball-mills  should  be 
fed  with  no  larger  ore  than  that  which  will 
pass  a  3  in.  ring.  With  fine  ore  the  balls  are 
apt  to  bed,  as  it  were.  Actual  weighings  have 
shown  that  a  3  in.  feed  is  crushed  faster,  and 


the  wear  of  steel  less,  than  when  the  feed  is 
about  1  in.  with  a  lot  of  fine. 

Grading  analyses  from  ball-mills  at  different 
plants  are  given  in  Table  II. 

With  the  exception  of  the  Associated  and 
Great  Boulder,  whose  screens  are  30  by  30, 
the  others  are  about  27  by  27.  They  are 
fairly  uniform,  although  the  —150  is  low  at 
the  Associated,  Associated  Northern,  and  Kal- 
gurli for  some  reason  not  understood.  The 
ball-mill  does  not  make  so  much  —  150  as  the 
Griffin  and  other  pulverizers. 

The  coarse  screens  used  to  be  fixed  to  the 
mill  by  studs,  but  a  local  improvement  was  in- 
troduced in  fitting  them  on  with  Ij  in.  angle- 
iron,  bent  to  circle  and  bolted.  A  large  num- 
ber of  bolts  are  used  in  a  mill,  and  cost  a  good 
deal.  For  some  reason,  perhaps  expansion  of 
plates  due  to  heat,  or  loose  plates,  these  break 
and  fall  into  the  mill,  and  then  a  lot  of  coarse 
ore  gets  through  the  bolt-hole  to  the  space  be- 
tween the  mantle  and  screens,  causing  the  mill 
to  run  out  of  balance.  Experienced  millmen 
soon  detect  this.  On  account  of  this  trouble, 
there  is  a  difference  of  opinion  as  to  the  use 
of  the  baffle-plates  fixed  to  the  return  scoop- 
plates  in  the  mill. 

The  fine  screens  should  be  brushed  once 
daily,  if  the  ore  is  dry,  and  oftener  if  damp, 
by  a  wire  brush.  They  last  from  30  to  40 
days,  providing  no  stones  work  out  and  tear 
them.  When  the  grinding-plates  get  thin  and 
nearly  worn  to  the  mantle- plates,  the  mill  re- 
quires re-lining.  This  is  done  differently  in 
several  plants  ;  some  millmen  prefer  to  have  a 
spare  set  of  mantles  and  fix  on  the  plates  at 
leisure,  and  when  the  time  comes  for  re-lining, 
just  to  take  out  those  worn  out,  and  fit  in  the 
prepared  plates,  this  taking  about  10  hours 
with  6  men  ;  while  others  consider  it  best  to 
leave  the  mantles  in  place,  and  cut  off  the  old 
grinding-plates,  and  fit  new  ones  as  they  pro- 
ceed. This  can  be  done  in  about  the  same 
time,  but  is  awkward,  heavy,  and  hot  work 
inside  the  mill.  There  are  several  little  points 
in  practice  on  which  we  shall  never  be  agreed, 
but  their  effect  is  trifling. 

A  No.  5  ball-mill,  including  foundations, 
may  be  erected  for  ^600,  and  a  No.  8  for 
;^1000,  bin  and  conveyors  not  included.  The 
former  will  cost  about  ^300  yearly  for  main- 
tenance. 

As  regards  wet- crushing,  I  have  seen  No.  4 
mills  at  work  in  Broken  Hill  plants  crushing 
jig-middling  that  passed  a  8  mm.  screen;  a 
No.  5  on  the  Lake  View  Consols  crushing 
sulphide  ore  ;  and  the  No.  5  at  the  Chaffers 
working  on  the  soft,  schistose,  oxidized  ore. 


AUGUST,    1911 


145 


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146 


THE    MINING    MAGAZINE 


In  the  first  instance  the  mills  could  not  show      and  a  ball-mill  for  the  Krupp  firm,  and  the 
great  efficiency  on  such  feed  ;  in  the  second,      latter  crusher  showed  an  output  of  40%  above 

the  battery,  even  the  dry  mill  being  better  on 
the  same  ore.  I  am  convinced  that  on  a  thor- 
ough trial,  all  things  being  equal,  the  ball-mill 
will  show  a  greater  output  and  efficiency  than 
the  stamp -battery.  Will  somebody  take  up 
this  question,  and  show  that  the  modern  heavy 
gravitation  stamp  is  not  the  most  economical 
crusher  for  its  present  work  and  that  there  are 
other  machines  that  can  do  the  work  better  ? 

Costs  of  ball-milling  are  given  in  Table  III. 
The  methods  of  segregation  of  costs  are  not 
uniform,  as  will  be  noted  at  once.  On  some 
mines  spares,  stores,  and  repairs  are  lumped 
together.  The  cost  of  power  is  high  at  the 
Perseverance  and  South  Kalgurli  on  account 
of  motor-driving.  The  Associated  is  in  a  state 
of  transition  from  the  old  No.  5  mills  to  the 
No.  8  size.  The  Great  Boulder  has  lately 
installed  a  high-class  steam-engine,  and  it  is 
expected  to  reduce  the  cost  of  power  to  the 
above  figure. 


the  mill  never  had  a  real  trial,  as  the  grinding- 
pans  and  tube-mills  were  already  overtaxed ; 
while  at  the  last-named  the  ore  is  so  soft  that, 
in  any  comparison  with  stamps  on  hard  ore, 
it  could  not  be  used.  Some  years  ago  the 
Eclipse  mine  here  had  ten  900  lb.  stamps 
crushing  similar  ore  to  the  Chaffers  at  the 
rate  of  10'5  tons  per  stamp  per  diem  through 
a  20  mesh  screen ;  so  the  capacity  of  the 
Chaffers  ball-mill  of  93  to  100  tons  through 
a  26  mesh  is  somewhat  better  than  the  10 
stamps.     The  wet  mill  product  is : 


+  120 3'56 

+  150 7"59 

-150 57'69 


+  40    10'60 

+  80    16"12 

+  100 +44 

The  ore  is  crushed  with  weak  cyanide  solu- 
tion in  the  proportion  of  1*6  to  1.  The  wear  and 
tear  in  the  wet  mill  is  almost  twice  as  heavy  as 
in  the  dry,  the  grinding-plates lasting  105  days. 

Max  Drott  made  some  comparative  tests 
on  hard  quartzite  ores  between  a  5-stamp  mill 


Table 

I.     Details  of  Ball-Mill  Practice 

at  Kalgoorlie 

(dry-crush 

ng)- 

Number 

of 

Mills 

Weight  of 
Balls 

lb. 

Screens 

Speed 
R.P.M. 

Power 
H.P. 

Drive 

Capacity. 

Steel 
Consump- 
tion 

lb.  per  ton 

Life  of 

Grinding 

Plates 

Mine 

Tons  Daily 

Days 

Associated  ... 

4  No.   8 

4480 

30X30 

21 

60 

Belt  from  shaft ... 

92-95 

050 

170 

Associated  Northern 

Chaffers      

Great  Boulder 

6     „     5 
3     „     5 

3  „     5 

4  „     8 

2240 
2350 
2300 
4480 

25  X  25 
27X27 
27X27 
30X30 

25 
26 
25 
24 

23 
18 
25 
60 
25 

Beltfromshaftand 
friction  clutch 

43 
40 
40 

80-90 

032 

074 

064 

270 
180 

105 

Kalgurli      

Perseverance 
South  Kalgurli 

9     „     5 

8     „     8 
3     „     8 

2200 
4400 
4480 

26X26 
27X27 
27  X  27 

25 
24 

24 

60 
65 
30 

Belt  from  shaft... 

Motor  and  Belt ... 

,,             . . . 

40 
100 
95-100 

045 
065 
0.47 

300 
118 
210 

1     „     5 

2800 

— 

— ■ 

— 

On  an  average,  63,000  tons  monthly  are  dry-crushed  in  ball-mills  on  the  Kalgoorlie  goldfield. 

Table  II.  Grading  Analyses. 


Name 

-1-30 

-f40 

+  60 

+  80 

+  100 

+  120 

+  150 

-  150 

Associated  ... 



1616 

15  66 

10  46 

643 

376 

346 

44  00 

Associated  Northern 

— 

1120 

20-10 

8  30 

1180 

320 

2  00 

43  60 

Chaffers      

— 

1025 

1319 

860 

725 

270 

2-70 

5630 

Great  Boulder       

100 

580 

1420 

870 

900 

2  30 

230 

5200 

Kalgurli      

— ■ 

8-20 

1800 

13-40 

910 

240 

240 

4530 

Perseverance          

020 

380 

2000 

7-80 

540 

400 

4  00 

5420 

South  Kalgurli       

— 

1020 

2120 

600 

2  60 

3  10 

3  10 

55-90 

Table  III.  Cost  in  Pence  per  Ton. 


Mine 

Wages 

Power 

Spares 

Stores 

Repairs 

Sundry 

Total 

Associated      

6-45 

1378 

673 

267 

0  49 

— 

3011 

Associated  Northern 

5-87 

12-08 

4-73 

1-42 

0  10 

— 

24-22 

Chaffers 

209 

1064 

— 

025 

6-88 

1-71 

21-57 

Great  Boulder 

1-81 

9-75 

— 

626 

— 

— 

17-82 

Kalgurli 

— 

1523 

— 

749 

— 

— 

22-72 

Perseverance 

321 

1918 

332 

046 

Oil 

0-54 

26-84 

South  Kalgurli          

205 

20 -82 

554 

— 

368 

0-21 

3230 

AUGUST,    1911 


147 


PRECIS  OF  TECHNOLOGY 

Shaft  Sinking  in  Wet  Ground. — The  Great  Central 
Railway /o/<;'»a/  for  March  contains  an  account  of 
the  sinking  of  shafts  at  the  Bullcroft  colliery  near 
Doncaster,  Yorkshire,  by  means  of  the  freezing  pro- 
cess, through  wet  strata.  Two  shafts  were  commenced 
in  June  1908,  and  all  went  well  until  a  depth  of  100  ft. 
was  reached,  when  water  started  to  come  in  at  the 
rate  of  1000  gal.  per  minute.  Iron  tubbing  was  inserted 
and  sinking  was  started  once  more.  In  February  1909 
when  the  depth  was  180  ft.  a  more  serious  influx  of 
water  took  place,  so  centrifugal  pumps  were  employed 
capable  of  raising  over  6000  gal.  per  min.  This  how- 
ever proved  of  no  avail,  as  the  ground  collapsed  at  the 


bottom  of  the  shafts.  It  was  then  decided  to  obtain 
the  advice  and  help  of  the  Shaft  Freezing  Company, 
and  under  the  direction  of  Emil  Dietz,  the  freezing  of 
the  ground  was  undertaken.  For  this  purpose  26  holes 
were  bored  around  each  shaft  along  the  circumference 
of  a  circle  27  ft.  diam.,  the  shafts  being  16  ft.  6  in. 
diam.  These  holes  were  sunk  to  300  ft.  and  freezing 
tubes  inserted.  An  ammonia  plant  was  erected  and 
by  its  means  brine  containing  26%  magnesium  chloride 
was  cooled  to  minus  12^C.  This  was  forced  into  the 
freezing  tubes  by  pumps.  The  results  at  first  were 
disappointing  because  the  water  continued  to  flow 
from  the  mouth  of  the  shafts.  It  was  found  to  be 
absolutely  necessary  that  the  flow  should  be  stopped, 
so  an  iron  cap,  20  ft.  high  and  15  ft.  6  in.  diam.,  was 


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VERTICAL    SECTION    OF   BULLCROFT   SHAFTS. 


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'o~o-o 

Freezing  Tubes  round  Shaft. 


fixed  at  the  mouth  of  the  shafts.  This  efleclively 
stopped  the  water  from  rising,  and  three  months  after- 
wards it  was  possible  to  draw  the  water  from  the 
shafts.  Previously  to  doing  so,  a  number  of  test  holes 
were  bored  to  180  ft.  depth  and  any  ca\  ities  discovered 
were  stopped  by  cement.  The  unwatering  was  com- 
menced at  No.  1  shaft  on  October  25.  1910.  and  a  week 
later  sinking  operations  were  resumed.  No.  2  shaft 
was  afterward  unwatered  and  sinking  recommenced. 
The  brick  lining  was  replaced  by  cast-iron  tubbing, 
and  at  a  depth  of  307  ft.  the  bed  plates  for  the  tubbing 
were  inserted.  Below  this  depth  it  was  not  necessary 
to  freeze  the  strata  as  they  were  not  water-bearing. 

The  article  also  gives  an  interesting  account  as  to 
the  sources  of  the  flow  of  water,  thus  elucidating  the 
cause  of  the  trouble. 


148 


THE    MINING    MAGAZINE 


Extraction  of  Mercury  from  Low-grade  Cinnabar 

Ores. —  In  the  Australian  Mining  Standard  for 
June  8,  C.  A.  Mulholland  gives  an  outline  of  a  wet 
process  that  he  has  used  on  a  small  scale  for  extract- 
ing cinnabar  from  low-grade  ore.  At  present  such 
ores  are  roasted  and  distilled  direct,  as  the  cinnabar  is 
too  friable  for  concentration.  Mr.  Mulholland  s  pro- 
cess utilizes  the  known  fact  that  cinnabar  is  soluble  in 
a  mixture  of  alkaline  sulphide  and  alkaline  hydrate. 
He  slimes  the  ore  in  a  solution  of  these,  and  subse- 
quently completes  the  reaction  in  an  agitator  heated 
by  a  steam  jet.  After  settlement  the  solution  is  re- 
moved and  the  residue  washed  with  another  solution 
intended  for  the  next  batch  of  ore.  The  solution  con- 
taining the  mercury  is  treated  with  zinc  hydrate  ;  zinc 
sulphide  and  mercurie  sulphide  are  precipitated.  The 
solution  then  contains  nothing  but  alkaline  hydrate, 
which  may  be  partly  reconverted  into  sulphide  by 
passing  sulphuretted  hydrogen  through  it.  The  mixed 
sulphides  in  the  precipitate  are  treated  with  dilute 
sulphuric  acid  and  steam  ;  sulphuretted  hydrogen  is 
evolved,  the  zinc  goes  into  solution,  and  the  precipi- 
tate consists  of  mercuric  sulphide  and  metallic  mer- 
cury, which  is  then  treated  in  the  usual  way.  Zinc 
hydrate  can  be  recovered  by  treating  the  sulphate  by 
alkaline  hydrate.  The  success  or  otherwise  of  this 
process  will  depend  on  the  prices  paid  for  the  alkaline 
sulphide  and  hydrate,  the  zinc  hydrate,  and  sulphuric 
acid,  and  on  the  amount  of  regeneration  possible. 
Also  the  ore  will  have  to  be  free  from  constituents 
such  as  metallic  oxides  ;  otherwise  the  consumption 
of  alkaline  sulphide  will  be  fatal  to  the  process. 

Mine  Temperatures. — At  the  May  meetmg  of  the 
Chemical,  Metallurgical,  and  Mining  Society  of  South 
Africa,  J.  Whitehouse  and  W.  L.  Wotherspoon  read 
a  paper  detailing  their  investigations  into  the  tempera- 
ture of  the  rocks  and  mine-air  on  the  Rand.  They 
gave  full  details  of  their  records  of  air  temperature  at 
the  Village  Deep,  before  and  after  the  installation  of 
the  ventilating  fan,  both  as  regards  temperature  and 
humidity.  In  the  part  of  the  paper  dealing  with  rock 
ternperatures,  the  authors  give  a  chart  on  which  are 
plotted  isolated  records  at  various  mines  on  the  Rand. 
They  deduce  a  mean  average  rise  of  temperature  of 
one  degree  Fahrenheit  for  every  253  9  ft.  of  depth 
vertically,  and  98°F  is  predicted  as  the  temperature 
at  7000  ft.  Five  years  ago  H.  F.  Marriott  calculated 
that  the  average  increase  of  temperature  was  one  de- 
gree for  208  ft.  The  authors  do  not  give  details  of  the 
method  of  recording  these  temperatures,  that  is  to 
say,  whether  they  represent  the  temperature  of  the 
rock  before  development,  or  of  the  rock  at  the  work- 
ing face  before  much  heat  has  had  opportunity  of 
escaping  into  the  mine  air.  Their  figures  show  a  lower 
rate  of  increase  of  rock  temperature  than  Mr.  Mar- 
riott's. No  doubt  further  information  will  be  pre- 
sented in  the  discussion  on  the  paper. 

Steel  Production  of  the  World. — The  Engineering 
and  Mining  Journal  for  June  24  reviews  the  progress 
of  the  steel  industry  of  the  world.  The  total  produc- 
tion for  1910  was  estimated  at  58  million  metric  tons, 
as  compared  with  53^  million  tons  the  year  before. 
The  increase  is  due  partly  to  the  general  recovery  of 
business  from  the  slump  of  1907,  and  partly  to  the  in- 
creasing use  of  steel  in  place  of  cast  iron,  wrought 
iron,  and  wood.  Cement  is  the  only  serious  rival  to 
steel  nowadays,  and  even  its  use  involves  the  employ- 
ment of  much  steel.  The  above  remarks  refer  especi- 
ally to  the  United  States,  where  95^%  of  the  pig  iron 
production  goes  to  the  steel  plant,  and  to  Germany, 
where  the  proportion  is  92^%.  In  Great  Britain  steel 
has  not  replaced  wrought  iron  to  anything  like  the 


same   extent,    for   the    reliability   and    toughness   of 

wrought  iron  are  still  appreciated.     The  following  are 

the  figures  for  the  production  of  steel,  in  metric  tons, 

of  the  three  chief  countries  : 

United  Great 

States  Germany        Britain 

Converter  : 

Acid 9,563,376        171,108     1,156,313 

Basic 8,030,571         651,268 

Open-hearth  : 

Acid 1,231,575        252,148     2,695,482 

Basic 15,537.006     5,125,421     1,603,793 

Crucible 124,260  83,202      

Electric,  etc 56,220  36.188      

Total 26,512,437  13,698,638     6,106,856 

Proportion   of    steel 

topigiron 956  926  58-8 

The  adoption  of  the  basic  or  acid  process  is  of  course 
determined  by  the  nature  of  the  ores,  but  this  does  not 
account  entirely  for  the  differences  in  practice.  For 
instance  nearly  60%  of  the  German  steel  is  made  in  the 
basic  converter,  but  this  process  is  not  employed  at  all 
in  the  United  States,  though  60%  of  the  steel  pro- 
duced there  is  basic.  Exact  comparison  is  not  possible, 
because  of  differences  in  the  methods  of  classification, 
especially  at  the  borderland  between  mild  steel  and 
puddled  bars.  The  British  figures  are  also  incom- 
plete, as  no  returns  are  available  for  crucible  steel  and 
electric  steel. 

Determining  Copper  in  Pyrite. — The  Engineering 
and  Mining  Journal  for  June  17  contains  a  transla- 
tion of  an  article  by  W.  N.  Iwanow  that  appeared  in 
Chemiker  Zeitung  for  May  18,  giving  a  new  method 
of  determining  copper  in  crude  and  spent  pyrite.  This 
is  based  on  the  suggestion  made  by  Groeger  in  1891 
that  by  heating  pyrite  (FeSj)  with  pulverized  metallic 
iron,  the  monosulphide  is  formed,  and  that  the  test 
reaction  would  thus  be  simplified.  Iwanow  follows 
up  this  method  and  applies  it  to  spent  pyrite  as  well 
as  raw  pyrite,  and  shows  that  by  heating  the  Fe.^Oa 
with  metallic  iron,  the  monoxide  (FeO)  is  formed, 
which  is  easily  soluble  in  hydrochloric  acid.  Thus 
the  copper  present  in  the  pyrite  is  readily  separated 
and  determined.  The  author  describes  his  method  in 
detail  thus  :  Three  grammes  of  finely  pulverized  crude 
or  spent  pyrite  is  mixed  with  an  equal  quantity  of 
powdered  iron  and  put  into  a  tube  of  thin  glass  about 
3  in.  long  by  gin  diameter,  closed  at  one  end  and  open 
at  the  other.  The  mixture  is  covered  with  a  thin  layer 
of  finely  divided  iron,  and  the  tube  heated  for  a  few 
minutes  over  a  Bunsen  burner  to  a  red  heat.  It  is 
then  placed  with  its  contents  in  an  Erlenmeyer  flask  of 
250  cc.  capacity,  and  a  few  drops  of  water  squirted  on 
it,  when  it  will  burst  to  pieces.  After  cooling,  50  cc. 
HCl  is  poured  in  and  the  flask  is  heated  on  the  water- 
bath  until  the  fused massiscompletelydissolved.  which 
will  take  about  half-an-hour.  As  some  HjS  is  freed 
in  this  operation,  the  copper  is  partly  precipitated. 
Then  the  solution  is  diluted  to  200  cc.  and  a  vigorous 
current  of  H.,S  passed  through  it.  The  precipitate  of 
CuS  is  filtered  off  with  other  impurities,  and  dissolved 
in  HNO3.  The  iron  is  precipitated  with  ammonia  and 
the  copper  determined  electrolytically.  The  copper 
sulphide  may  also  be  dissolved  directly  on  the  filter 
with  HNO3,  the  solution  neutralized  with  ammonia 
and  electrolysed .  The  author  gives  tables  of  compara- 
tive results  obtained  by  his  method  and  by  Lunge's 
and  the  nitric  acid  methods.  The  question  of  accu- 
rately determining  the  small  amounts  of  copper  in 
pyrite  is  an  important  one,  as  those  connected  with  the 
sale  of  cupriferous  pyrite  well  know. 


AUGUST,    1911 


149 


SHme  Settlement. — In  the  Monthly  Journal  of  the 
Chamber  of  Mines  of  Western  Austraha  for  May,  B. 
L.  Gardner  describes  a  new  device  for  thickening 
shme  adopted  at  the  Sons  of  Gwalia  mine.  The  shme 
at  this  mine  is  slow-settHng  and  requires  a  large  plant 
for  settlement  by  stages.  Owing  to  the  large  amount 
of  magnesium  salts  it  is  impossible  to  use  lime  for 
hastening  the  operation.  The  method  adopted  is  to 
provide  additional  areas  for  settlement  by  inserting 
in  the  spitzkasten  a  series  of  inclined  sheets  of  corru- 
gated iron,  thereby  increasing  the  rate  of  settlement. 
The  principle  of  this  idea  may  be  explained  by  the  ex- 
periment illustrated  in  the  accompanying  Fig.  1.  A 
glass  cylinder  full  of  slime  was  placed  in  the  ordinary 
upright  position,  and  the  rate  of  settlement  was  found 
to  be  40  mm.  per  minute.  It  was  then  re-agitated  and 
inclined  at  45'  as  in  the  illustration  ;  the  rate  was  then 
found  to  be  ISO  mm.  per  minute.  The  reason  for  this 
increase  in  the  rate  is  that  on  the  upper  side  of  the 
cylinder  a  stream  of  clear  water  flows  upward  and 
joins  the  supernatant  clear  water  above  the  pulp.  The 


Fig.  1. 


particles  of  solid  settling  in  a  downward  direction  leave 
upon  the  lower  face  of  the  tube  a  layer  of  clear  water, 
which  is  displaced  upward  owing  to  its  lower  density 
than  the  pulp.  In  applying  the  principle,  the  inclined 
iron  sheets  are  fixed  as  shown  in  Fig.  2.  The  corru- 
gations serve  the  purpose  of  deflecting  the  flow  into 
narrow  streams  which  do  not  disturb  the  slime.  It  is 
best  to  set  the  sheets  parallel  to  the  current  so  as  to 
impede  the  flow  of  the  pulp  as  little  as  possible.  In 
comparative  tests  with  and  without  the  sheets  the  fol- 
lowing results  were  obtained  : 


Spitzkasten 

24  by  8  ft. 

with  settling  device. 

Spitzkasten 

24  by  24  ft.  without 

settling  device. 

Amount  settled 
lb.  per  minute.. 

49-1 

155-6 

Percentage  of  dry 
slime 

411 

26- 1 

same  per  unit  area  of  the  spitzkasten,  but  that  with 
the  settling  device  the  resulting  pulp  is  50%  thicker. 
Thus  the  efficiency  of  settlement  is  notably  increased, 
by  means  of  a  cheap  apparatus  that  can  be  applied 
without  trouble  to  any  existing  plant. 

Specular  Iron-Ore  in  Huelva. — Diaria  de  Httelva 
for  April  4  reprints  an  article  from  Revista  Minera 
written  by  Juan  Hereza.  on  the  specular  iron-ore  de- 
posits in  the  province  of  Huelva,  Spain.  In  Huelva, 
according  to  Gonzalo  Tariso,  the  Archaean  formation 
is  represented  by   Laurentian  and   Huronian  rocks. 


The  tests  were  made  on  sulphide  slime,  the  inflowing 
pulp  containing  15  to  18%  solid.  It  will  be  seen  that 
the  amount  of  pulp  fed  per  minute  is  practically  the 


-P/OQ- 

Fig.  2. 

The  former  are  composed  of  micaceous  gneiss,  re- 
placed here  and  there  by  cordierite  (iolite)-.  horn- 
blende-, and  epidote-gneiss,  or  are  substituted  by 
granitoid  gneiss.  At  the  base  of  the  upper  sub- 
division (Huronian)  mica  schists  {micacitas)  a.re  little 
developed  ;  there  usually  occur  in  contact  with  the 
gneiss  of  the  lower  subdivision  (Laurentian).  taicose 
schists  with  sericite,  which  contain  more  and  more 
clay  until  they  become  phvllites  or  argillaceous-talcose 
phyllades.     In  the  gneiss,  as  well  as  in  the  taicose 


150 


THE    MINING    MAGAZINE 


schists  and  phyllites,  are  intercalated  beds  of  crystal- 
line limestone.  The  Jabugo  deposits  occur  in  the 
talcose  schists  and  at  the  gneiss  contact. 

The  following  explorations  have  been  effected  by 
the  Soria  Mining  Co.  :  (1)  Costeaning-pits  (calicatas) 
exposing  specular  iron-ore  ;  (2)  A  trench  (trinchera) 
opened  at  one  point  on  a  bed  of  specular  iron-ore  5 
metres  thick  ;  (3)  Four  shafts,  15  to  20  m.  deep,  in 
the  bed  or  beds  which  constitute  the  formation.  So 
far  only  one  bed  of  iron-ore  is  known,  but  the  com- 
pany will  put  down  bore-holes  and  deepen  one  of  the 
shafts  in  order  to  ascertain  how  many  beds  exist,  and 
to  exploit  the  same. 

The  ore  is  specular  iron-ore  {oligisto)  containing 
some  magnetite.  The  iron  varies  from  45  to  70% 
(average  60%).  Silica  is  not  abundant,  there  is  little 
sulphur,  and  only  traces  of  phosphorus.  The  matrix 
is  calcareous  (formed  by  substitution)  and  quartzose. 
The  quartz  is  scarce  and  occurs  in  small  veins  with 
pyrite  and  chalcopyrite,  and  sometimes  with  galena. 
This  appears  to  indicate  that  one  single  appearance 
(una  sola  aparicion)  of  complex  sulphides  may  have 
given  rise  to  the  greater  part  of  the  metalliferous  de- 
posits of  Huelva  (excepting  those  of  manganese,  whose 
origin  is  very  different),  thus:  (1)  The  sulphurous 
emanations  encountered  at  the  contact,  or  near  the 
eruptive  centres,  places  of  easy  access  to  points  where 
the  schistose  strata  have  been  broken  and  triturated 
by  dynamic  action,  and,  in  this  way,  the  great  masses 
of  ferro-cupriferous  pyrite  may  have  been  formed. 
Epigenic  action,  due  to  the  upper  hydrostatic  circu- 
lation, has  hydroxidized  the  upper  part  of  the  de- 
posits, and  produced  a  kind  of  natural  cementation  in 
the  middle  portion  (mesogenic),  enriching  them  in  a 
zone  of  variable  thickness,  until,  entering  the  lower 
regions  (endogenic)  we  gain  a  proximate  idea  of  the 
average  composition  of  the  primary  sulphurous  car- 
riers [aportes).  Another  order  of  the  phenomena  of 
metamorphism  has  afterwards  produced  the  crystalli- 
zation of  the  mass  originally  in  a  pasty  condition. 

(2)  A  portion  of  the  sulphides  has  been  oxidized  or 
has  been  directly  dissolved  in  acid  waters,  giving  the 
sulphides  mobility  to  reach  points,  where,  by  the 
special  constitution  of  the  formation,  substitution  de- 
posits have  been  formed,  the  different  metals  forming 
part  of  such  in  a  proportion  depending  on  the  quan- 
tity of  each  in  the  place  of  origin,  on  the  grade  of 
solubility  of  the  salts,  saturation  of  the  solutions, 
heat,  pressure,  etc.  Iron  sulphide  constitutes  more 
than  95%   of  the  normal  pyrite. 

(3)  Another  portion  of  the  sulphides  dissolved,  may 
be,  by  alkalies,  were  also  able  to  travel  far  from  the 
eruptive  centres,  and  form  concretionary  deposits  of 
complex  sulphides,  which  do  not  show  a  banded  struc- 
ture {estriictura  fajcada)  but  which  are  confusedly 
mixed  [confiisamente  inezclados)  as  coming  from 
one  single  centre. 

The  band  of  Archaean  rocks  runs  from  east  to  west 
in  the  province  of  Huelva,  and  is  continued  into  Por- 
tugal, in  which  country  mines  of  specular  iron-ore 
and  magnetite,  in  connection  with  crystalline  lime- 
stone have  been  explored  from  ancient  times,  so  that 
it  would  not  be  strange  if  analagous  deposits  were 
discovered  hereafter  in  Cortegana,  Aroche,  and  Rosal 
de  la  Frontera  (Spain). 

The  Gold  Industry  of  the  Rand. — On  June  28  the 
annual  James  Forrest  lecture  was  delivered  to  the  In- 
stitution of  Civil  Engineers,  by  F.  H.  Hatch,  the  sub- 
ject chosen  by  him  being  the  "  Past,  Present,  and 
Future  of  the  Gold-Mining  Industry  of  the  Witwaters- 
rand."  We  cannot  do  full  justice  to  this  paper  on 
account  of  the  exigencies  of  space,   so  we  will  deal 


chiefly  with  the  historical  statement  and  the  author's 
own  views  and  opinions. 

The  growth  of  the  Rand  was  at  first  slow.     Some  of 
the  earliest  workers  believed  that  the  auriferous  gravel, 
exposed  in  shallow  open  workings,  was  a  superficial 
deposit  like  the  placers  of  California  and  Australia. 
But  the  true  character  of  the  conglomerate  beds  was 
soon  realized  by  those  who  had  some  geological  know- 
ledge, and  by  1887  stamp-mills  were  in  operation.  The 
output  from  the  Witwatersrand  mines  for  that  year  was 
;r81,045.      Down  to  the  water-level,  at  a  vertical  depth 
varying  from  200  to  300  feet,  the  conglomerate  beds 
were  free-milling.     Below  the  water-level  the  colour 
of  the  rock  changed  from  red  to  blue  ;  the  ore  became 
pyritic  ;  and  the  gold  was  no  longer  so  amenable  to 
amalgamation.     This  was  the  first  difficulty  that  had 
to  be  overcome.     Up  to  the  year  1890  the  treatment 
of  the  Rand  ore  consisted  of  crushing  in  stamp-mills, 
and  the  recovery  of  50  to  60%  of  the  gold  by  amalga- 
mation.    Usually  the  pulp  leaving  the  amalgamating 
plates  was  also  run  over  blanket-strakes,  with  the  ob- 
ject of  retaining  the  rich  black  sands  (that  is,  iron  ore 
produced  by  the  oxidation  of  pyrite).     In  some  cases 
Frue  vanners  were  in  use,  the  resulting  concentrate 
being  sold  to  the  chlorination  custom  works.    But  the 
tailing  received  no  further  treatment,  and  being  con- 
sidered valueless  was,  where  the  ground  permitted  it, 
allowed  to  flow  away,  or  at  least  no  great  pains  were 
taken  to  conserve  it.     The  knowledge  that,  when  the 
free-milling  ore  became  exhausted,  the  pyritic  nature 
of  the  rock  would  increase  the  difficulty  of  gold  ex- 
traction,   caused  the  greatest  anxiety  on  the  Pand. 
But  the  successful  introduction  of  the  cyanide  process 
in  1890  dissipated  all  these  fears,  and  anew  era  in  the 
history  of  Rand  gold  mining  was  inaugurated  at  that 
date.     It  soon  swept  away  all  the  costly  methods  of 
concentration    by    Frue   vanners   and    other  shaking 
tables,  and  the  subsequent  roasting  and  chlorination 
of  the  pvritic  concentrate  ;  and  thus  cheapened  the 
treatment  while  it  increased  the  extraction.     At  first 
on  account  of  its  slime  content  not  more  than  50%  of 
the  pulp  was  suitable  for  treatment  by  percolation  with 
cyanide  solution  ;  and  of  the  gold  contained  in  this, 
some  65%  was  extracted.     In  other  words,  only  30% 
of  the  gold,  left  in  the  pulp  from  the  amalgamating 
tables,  was  recovered.     Hennen  Jennings  then  intro- 
duced the  method  of  treatment  by  hydraulic  classifiers 
whereby  a  considerable  proportion  of  the  slime  was 
eliminated  and  a  sand  product  obtained,  which  could 
be  run  direct  to  the  leaching-vats.  A  further  improve- 
ment was  the  use  of  the  Butters  and  Mein  distributor. 
The  treatment  of  the  slime,  which  for  some  time  after 
the  introduction  of  the  cyanide  process  remained  a 
waste  product,  was  the  problem  which  next  engaged 
the  attention  of  the  Rand  metallurgists.     In  the  year 
1894  experiments  were  made  independently  by  Charles 
Butters,  on  accumulated  slime  at  the  Robinson  mine, 
and  by  J.  R.  Williams  at  the  Crown  Reef  mine,  with 
such  success  that  thereafter  slime  treatment  became 
general.     Briefly,  the  process  consisted  in  causing  the 
slime  overflowing  from  the  sand-collectors  to  settle  by 
the  addition  of  lime,  and  the  subsequent  removal  of 
the  bulk  of  the  water  by  decantation.     The  concen- 
trated slime,  so  obtained,  was  agitated  with  cyanide 
solution,  which  was  ultimately  drawn  off  by  decanta- 
tion.    The  separation  of  sand  from  slime  by  the  hy- 
draulic classifier  and  the  decantation  method  for  the 
removal  of  water  or  solution  from  sand  or  slime,  are 
now  giving  place  to  the  use  of  diaphragm-cones  and 
vacuum-filters. 

Dr.  Hatch  proceeds  to  describe  the  Caldecott  classi- 
fying cone  and  the  Butters  filter,  and  enumerates  their 


AUGUST,    1911 


151 


applications.  He  discusses  the  relative  advantages  of 
zinc  shavings  and  zinc  dust  as  precipitant,  and  re- 
views the  methods  of  comminution.  He  voices  the 
opinions  as  regards  other  machines  than  stamps,  and 
the  difficulties  of  introducing  innovations  thus  : 

Now  that  the  stamp-mill  has  been  shown  to  be  a 
crushing  machine,  representing  only  one  stage  in  a 
series  of  successive  comminuting  operations,  namely 
(1)  by  rock-breakers,  (2)  by  heavy  stamps,  (3)  by  tube- 
mills,  it  may  be  questioned  whether  the  work  of 
the  stamps  (namely,  reduction  from  1  to^in.)  could 
not  be  equally  well  done  either  by  rolls,  or  by  mills  of 
the  Chilean  type,  or,  perhaps,  by  a  combination  of 
both.  The  combination  is  favoured  in  the  United 
States.  According  to  Philip  Argall,  Chilean  mills  of 
6  ft.  diameter,  running  at  33  revolutions  per  minute, 
on  Cripple  Creek  ores,  will  reduce  4  tons  per  hour, 
60%  of  which  will  pass  150-mesh,  the  feed  having  been 
previously  rolled  to  pass  a  g  in.  aperture.  In  this  case, 
rolls  and  Chilean  mills  do  the  work  of  stamps  and  tube- 
mills  on  the  Rand.  The  charge  is  sometimes  made  that 
Rand  metallurgists  are  unduly  conservative,  and  that 


underground  inclined  shafts  will  also  be  driven  in  the 
footwall.  These  will  serve  as  intakes  for  the  air  cur- 
rent, and,  being  in  solid  ground,  will  reduce  the  loss 
of  air  by  short-circuiting  to  a  minimum.  Since  these 
main  ventilating  roads,  instead  of  following  the  regu- 
lar course  of  the  reef-plane,  are  driven  straight,  they 
will  also  be  admirably  adapted  for  cheap  mechanical 
transport.  The  use  of  sand-filling  will  incidentally 
aid  ventilation  by  restricting  the  spaces  to  which  the 
currents  of  air  can  gain  access. 

The  author  then  discusses  the  probable  future  of  the 
Rand,  his  arguments  being  based  on  the  cost  of  mining 
and  the  limit  of  profitableness  of  the  ore.  He  takes 
the  figures  for  the  first  quarter  of  1911  for  the  results 
at  the  Robinson,  Primrose,  Simmer  &  Jack,  East  Rand 
Proprietary,  Witwatersrand  (Knights),  Knight's  Deep, 
and  Glencairn,  and  shows  that  their  average  costs 
were  13'8s.  This  result  has  been  brought  about  by  in- 
creasing, to  their  economic  limit,  the  size  of  the  units 
used  in  the  various  operations,  such  as  trucks,  stamps, 
tube-mills,  vats,  pumps,  etc.  ;  by  the  simplification 
of  the  methods  of  handling  ore  ;  and  by  replacement. 


OUTCSOPS    OF    THE    WITWATERSRAND    SERIES. 


they  are  averse  to  the  introduction  of  new  processes, 
which  may  even  have  been  shown  to  be  successful 
elsewhere.  But  this  conservatism  is  justified  ;  the 
scale  of  operations  on  the  Rand  is  so  enormous  that 
even  minor  changes  in  existing  practice  cannot  be 
risked,  without  prolonged  investigation  and  actual 
trial  under  regular  working  conditions  on  the  spot. 
The  seriousness  of  even  a  small  loss  per  ton,  which 
might  result  from  an  unwise  change  of  practice,  is 
shown  by  the  fact  that  on  one  of  the  largest  plants  a 
difference  of  01  dwt.  per  ton  is  equivalent  to  ;;/^18,000 
worth  of  gold  per  annum. 

Dr.  Hatch  proceeds  to  review  the  underground 
problems  connected  with  labour,  dust,  ventilation, 
transport,  drills,  sand-filling,  and  power-production. 
As  regards  ventilation  he  remarks  that  it  is  hampered 
by  the  small  air-space  and  large  frictional  resistance  of 
the  rectangular  timbered  shafts,  at  present  in  use  on 
the  Rand.  For  this  reason  many  of  the  deeper  shafts 
of  the  future  will,  no  doubt,  be  of  the  circular  type, 
with  either  brick  or  concrete  lining.      Main  levels  and 


so  far  as  it  is  economical  to  do  so,  of  hand-labour  by 
mechanical  appliances.  Working  at  a  cost  of  liSs. 
per  ton  means  that  the  cost  of  development,  extraction, 
and  reduction,  including  administration  is  covered  by 
a  recovery  of  3j  dwt.  of  fine  gold  per  ton.  On  5  dwt. 
ore,  therefore,  this  would  allow  of  a  profit  of  nearly 
7s.  6d.  per  ton.  And  it  is  only  necessary  to  look  at 
the  value  of  the  ore  reserves  of  many  of  the  big  mines 
to  see  that  this  is  not  far  from  the  average  grade  of 
much  of  the  ore  which  the  engineers  propose  to  work 
in  the  near  future.  It  is  clear  that  over  a  considerable 
area  of  the  Rand  the  ai-erage  grade  of  the  orebodies 
is  not  much  above  5  dwt.  The  inclusion  of  large  ton- 
nages of  relatively  poor  reef,  which  formerly  were  con- 
sidered outside  the  range  of  practical  mining,  has 
been  made  possible  by  lower  operating  costs.  The 
grade  of  the  ore  crushed  has  fallen  in  consequence. 
This  does  not  necessarily  imply  that  the  increased 
depth  of  the  mines  has  caused  a  falling  ofl"  in  the 
actual  value  of  the  ore  deposit  considered  as  a  whole. 
The  author  has  not  been  able,  with  the  material  at 


152 


THE     MINING    MAGAZINE 


his  disposal,  to  come  to  any  definite  conclusion  on  this 
point ;  but  he  is  inclined  to  the  %'iew  that  a  gradual 
impoverishment  with  depth  does  exist.  It  would  be 
quite  possible  from  existing  records  and  assay  plans 
to  settle  this  really  vital  question,  but  hitherto  no  fig- 
ures relating  thereto  have  been  published  by  any  of 
the  big  houses. 

The  effect  of  this  increased  tonnage  and  diminished 
grade  on  the  life  of  the  Rand  goldfield  as  a  whole  is 
an  interesting  subject  for  speculation.  Some  few 
years  ago,  T.  H.  Leggett  and  the  author  estimated 
the  production  of  gold  to  be  expected  from  the  Main 
Reef  series,  if  worked  to  a  vertical  depth  of  6000  ft. 
Up  to  that  date  (1902)  the  Rand  had  already  produced 
gold  to  the  value  of  /76, 800, 000  ;  and  they  calculated 
that  another  ^1,233,500,000  could  be  produced  down 
to  the  depth  stated.  The  average  of  the  figures  for 
gold-recovery  used  in  the  estimate  was  38s.  to  the  ton. 
The  actual  recovery  at  the  time  averaged  42s.  It  has 
since  fallen  to  28s.  6d.  But,  on  the  other  hand,  large 
bodies  of  ore  are  now  being  worked  that  were  then 
passed  over  as  unprofitable  No  doubt,  to  a  large 
extent,  the  one  factor  cancels  the  other  ;  so  that  for 
the  purposes  of  a  rough  estimate  we  may  still  make 
use  of  the  sum  total  then  arrived  at. 

Between  the  years  1902  and  1911  the  Rand  has  pro- 
duced /1S7,000,000.  Deducting  this  figure  from  the 
sum  total,  there  remains  ;^1, 046, 000, 000,  which,  on 
the  basis  of  an  average  output  of  /30, 000, 000  per  an- 
num, is  equivalent  to  a  life  of  35  years,  down  to  a  ver- 
tical depth  of  6000  ft.  But,  if  at  still  greater  depths 
the  banket  should  contain  sufficient  gold  to  yield  a 
profit,  after  deducting  the  cost  of  working  (which, 
under  the  best  conditions  existing  at  the  present  time, 
is  12s.  6d.  or  about  3  dwt.  of  fine  gold  to  the  ton),  we 
may  rest  assured  that  it  will  be  worked.  The  limiting 
factors  are  (1)  the  mechanical  difficulty  of  raising  the 
ore  to  the  surface  from  such  great  depths,  and  (2)  the 
effect  of  the  temperature  gradient.  With  regard  to 
the  mechanical  question,  the  electrical  transmission  of 
power  applied  to  stage-winding  has  so  modified  the 
mining  engineer's  conception  of  the  depths  from  which 
hoisting  is  practicable,  that  it  is  now  generally  as- 
sumed that  there  are  no  mechanical  difficulties  that 
cannot  be  overcome  if  it  pays  to  do  so.  In  respect  to 
the  temperature  question,  Mr.  Marriott's  experiments 
have  shown  that  the  rock  temperature  at  7000ft.  would 
be  only  975°  F.,  and  with  efficient  ventilation  the  air 
temperature  would  of  course  be  considerably  lower. 
It  follows,  therefore,  that  for  all  practical  purposes  the 
whole  question  turns  solely  on  the  gold  content,  and 
what  that  may  be  at  a  vertical  depth  of  7000  or  8000 
ft.  no  one  can  tell.  This  much,  however,  may  be  said  : 
the  geological  structure  of  the  country  clearly  indicates 
the  continuance  of  the  conglomerate  or  banket  beds  to 
still  greater  depths  than  even  7000  or  8000  ft.  before 
the  bottom  of  the  great  synclinal  basin  of  the  Wit- 
watersrand  is  reached  ;  and,  beyond  that  point,  the 
beds  must  still  continue  until  they  rise  to  form  the 
southern  lip  of  the  basin,  known  to  exist  beyond  the 
Vaal  River.  On  the  previous  page  we  give  Mr. 
Hatch's  map  of  the  outcrops. 

Mining  at  Sudbury.  —  In  the  Engineering  and 
Mining  Journal  for  June  17,  Walter  R.  Crane  de- 
scribes the  method  of  mining  the  nickeliferous  veins 
at  Sudbury,  Ontario.  The  veins  are  wide  and  lenticu- 
lar, and  dip  steeply.  Dry-walling  is  used,  and  waste 
filling  is  drawn  by  rilling  from  exhausted  slopes  to  be 
used  again  below.  He  makes  a  comparison  between 
the  methods  and  those  adopted  at  the  Lake  Superior 
copper  mines,  taking  the  Trimountain  as  a  type  of  the 
latter. 


CURRENT    LITERATURE. 

Tunnel  Driving  in  the  Alps. — At  the  June  meet- 
ing of  the  American  Institute  of  Mining  Engineers, 
W.  L.  Saunders,  of  the  Ingersoll-Rand  Company, 
presented  a  lengthy  paper  on  the  driving  of  the 
Loetschberg  tunnel  in   Switzerland. 

Supporting  Mine  Roofs. — Mines  and  Minerals  for 
July  gives  a  report  on  tests  of  various  methods  of  sup- 
porting mine  roofs,  undertaken  by  Messrs.  Connor, 
Griffith,  and  McKibben,  while  studying  the  subsidence 
problem  at  Scranton,  Pennsylvania. 

Sea-Transport  of  Iron  Ore.— At  the  July  meeting 
of  the  Institution  of  Naval  Architects,  J.  Johnson  read 
a  paper  on  the  steamships  and  port  facilities  provided 
for  the  export  of  Swedish  iron  ore. 

Riffles  on  Concentrating  Tables.— In  the  July 
Bulletin  of  the  American  Institute  of  Mining  En- 
gineers, S.  A.  Krom  questions  the  value  of  riffles  on 
concentrating  tables,  and  describes  the  table  invented 
by  U.  S.  James  that  employs  no  riffles  at  the  top  end. 
Specific  Gravity  of  Pu\p.— Mines  and  Minerals 
for  July  reproduces  a  paper  by  F.  B.  Hyder,  read  be- 
fore the  Colorado  Scientific  Society,  describing  methods 
of  calculating  the  specific  gravity  of  slime-pulp  and  dry 
slime. 

Errors  in  Sampling.  —  In  the  Engineering  and 
Mining  Journal  for  June  24,  Louis  D.  Huntoon  dis- 
cusses the  errors  likely  to  arise  in  the  preparation  of 
the  assay-sample  from-  the  bulk  sample.  He  finds 
that,  just  as  in  producing  bulk  samples,  the  richer 
parts  go  into  the  fine,  so  that  the  return  of  oversize  on 
screening  must  be  carefully  managed,  in  fact  it  is  best 
that  screening  should  be  avoided.  The  material  should 
be  continually  mixed  after  each  operation,  and  self- 
discharging  riffles  of  the  Jones  type  should  be  used. 

Continuous  Cyanide  Process. — In  Metallurgical 
and  Chemical  Engineering  for  July,  John  E.  Roth- 
well  submits  a  proposition  for  making  the  slime  treat- 
ment process  continuous  by  eliminating  the  filter-press 
and  effecting  the  removal  of  the  gold  solution  and  the 
subsequent  washing  of  the  slime  by  means  of  a  series 
of  pulp  thickeners,  with  the  cyanide  solution  com- 
mencing with  the  last,  and  passing  step  by  step  up  to 
the  first  in  the  opposite  direction  of  the  flow  of  the 
slime  itself. 

Metallurgy  at  Liberty  Bell,— In  the  Mining  and 
Scientific  Press  for  June  24,  Charles  A.  Chase  des- 
cribes the  modern  cyanide  plant  at  the  Liberty  Bell 
mine,  Telluride,  Colorado. 

Metallurgy  at  Komata  Reefs.— In  the  Mining  and 
Scientific  Press  for  July  1,  S.  D.  McMiken  describes 
the  cyanide  practice  af  Komata  Reefs,  New  Zealand, 
where  Brown  &  McMiken  agitator  vats  (called  '  Pa- 
chuca  tanks '  in  America)  were  first  applied. 

Lead  Smelting  in  Missouri. — Mines  and  Minerals 
for  July  contains  an  article  by  Lucius  L.  Wittich 
describing  the  new  smelter  erected  at  Webb  City, 
Missouri,  for  treating  high-grade  galena  by  the  Scotch 
hearth. 

Symons'  Crusher. — In  the  Engineering  and  Min- 
ing Journal  for  July  22,  A.  H.  Reed  describes  a 
crusher  for  jig  middlings,  invented  by  Symons 
Brothers,  in  which  the  material  is  comminuted  by 
means  of  rotating  discs. 

Wood  Tin.  -  The  Mineralogical  Magazine  for  May 
contains  a  paper  by  J.  H.  Collins  describing  several 
.specimens  of  wood  tin  from  Cornwall  and  Mexico. 

Copies  of  the  original  papers  and  articles  men- 
tioned under  '  Precis  of  Technology  '  and  '  Current 
Literature  '  can  be  supplied  on  application  to  The 
Mining  Magazine. 


AUGUST,    1911 


153 


BOOKS  REVIEWED 

The  Witwatersrand  System.    By  W.  E.  Bleloch. 

pamphlet  and  map.       London  :    E.    Marlborough  & 

Co.    Price  42s.    For  salehy  The  Mining  Magazine. 

It  is  a  fact  worthy  of  note  that  all  those  banket 
beds  which  have  been  proved  to  be  important  were 
discovered  early  in  the  history  of  the  Rand  and  that 
in  spite  of  much  search  no  other  beds  containing 
similar  gold  contents  have  been  found  since.  The 
Main  Reef  series  in  the  Central  Rand ;  the  Van 
Ryn  in  the  Eastern  Rand  ;  the  Nigel  Reef  in  the 
Heidelberg  district  ;  the  Randfontein,  the  Botha's, 
and  the  Battery  Reef  series  in  the  Western  Rand  ; 
the  Buffelsdoorn  and  others  in  the  Klerksdorp  district  ; 
and  the  Rietfontein  series  lying  by  itself  to  the  north 
of  the  Main  Reef  series,  were  all  discovered  quite 
early  and  no  other  line  of  banket  of  comparable  value 
has  been  discovered  since.  At  the  same  early  stage 
the  several  other  horizons  of  poorer  banket  princi- 
pally above,  but  also  below,  the  Main  Reef  series  be- 
came known,  and  it  may  be  said  with  regard  to  such 
beds  also  that  no  important  later  additions  to  their 
number  have  been  made.  Not  only  did  the  early  pro- 
spectors discover  so  much,  leaving,  as  events  have 
turned  out,  their  successors  so  little  reward  outside 
of  that  which  might  come  to  them  from  the  develop- 
ment of  the  initial  discoveries,  but  in  the  same  note- 
worthy manner  the  early  geologists  and  engineers 
put  together  the  framework  of  the  structural  geology 
of  the  field  upon  which  their  successors  also  have 
been  content  to  build. 

The  wt)rk  done  since  those  days  has  bridged  many 
of  the  early  gaps  upon  the  surface  ;  has  established 
the  continuity  in  depth  ;  and  has  put  together  such  a 
record  of  structural  geology  and  stratigraphy  as  will 
afterward  doubtless  be  referred  to  as  classic.  From 
the  time  in  the  year  1886  when  gold  was  first  dis- 
covered in  the  banket  beds,  systematic  and  most 
effective  search  went  out  to  the  east  and  west  of  the 
point  of  discovery.  So  keen  was  this  search  and 
moved  by  so  much  impetus  that  breaks  in  the  surface 
continuity  were  spanned,  each  extension  becoming 
the  index  to  the  one  further  ahead.  Then  when  the 
breaks  became  too  big,  giving  the  Main  Reef  series 
space  to  change  beyond  recognition,  the  quest  was 
still  continued,  using  the  trend  of  the  enclosing  sedi- 
mentaries  as  a  guide,  until  in  the  end  the  encircling 
traverse  became  complete,  east  returning  to  the  start- 
ing point  through  west,  and  west  through  east.  It 
was  then  that  the  position  became  reviewed,  and  that 
ideas  concerning  the  correlation  of  the  different  beds 
to  one  another  shaped  themselves  slowly,  unforced, 
and  in  conformity  with  reason.  Among  other  deter- 
minations accepted  was  the  one  that  the  Van  Ryn 
series  in  the  east  was  the  continuation  of  the  Main 
Reef  series  of  the  centre,  this  dignity  falling  to  the 
former  because,  being  found  within  the  line  of  search, 
it  contained  important  resources  in  gold  and  was  of 
banket  identical  in  appearance  to  that  of  the  standard 
series.  All  the  work  done  since  then  and  all  the 
observations  made  have  confirmed  this  correlation, 
in  which  confirmation  the  gradual  lessening  of  the 
gap  between  the  workings  on  the  two  series  has  been 
the  most  important  factor.  This  gap,  caused  by  a 
thickness  of  more  recent  beds  upon  the  surface,  has 
given  way  before  the  advance  of  underground  work 
and  the  probing  of  diamond-drills,  till,  in  spite  of 
local  disturbances,  the  terminals  have  been  so  joined 
that  there  exists  in  the  mind  of  most  responsible 
persons  today  no  doubt  of  the  correctness  of  the  iden- 
tity of  the  two  series. 


Mr.  Bleloch  m  his  geological  map  of  the  Southern 
Transvaal  and  in  the  short  treatise,  '  The  Witwaters- 
rand System,'  which  accompanies  it,  questions  and 
refuses  this  identity,  affirming  at  the  same  time  that 
the  Van  Ryn  series  is  a  continuation  of  the  Rietfon- 
tem  series.  It  was  of  course  open  and  still  is  for  any- 
body to  bring  forward  and  submit  data  that  might 
bnng  the  acceptance  of  this  position  into  question, 
and,  in  doing  so,  to  leave  the  community  his  debtor, 
always  provided  that  proper  respect  were  paid  to  the 
effort  and  the  intelligence  of  previous  workers.  There 
is  however  very  little  of  submission  in  the  way  that 
Mr.  Bleloch  has  put  his  ideas  forward,  nor  does  he 
show  a  proper  regard  for  the  opinions  of  those  geolo- 
gists who  have  studied  the  same  ground  ;  he  alone 
therefore  would  be  to  blame  if  his  views  were  rejec- 
ted with  scant  consideration. 

Before  weighing  his  views  it  is  necessary  to  know 
the  position  generally  assigned  to  the  Rietfontein 
series.  It  was  long  held  that  this  was  a  banket  bed 
at  a  definite  horizon  in  the  lower  portion  of  the  Wit- 
watersrand system,  but  during  recent  years  this  view 
has  been  questioned,  more  particularly  by  Hatch  and 
Corstorphine,  who  state  that  this  series  has  certain 
resemblances  to  the  overlying  Elsburg  series,  which 
again  they  considered  to  be  in  all  probability  uncom- 
formable  to  the  beds  of  the  Witwatersrand  system. 
Mr.  Bleloch,  in  affirming  the  identity  of  the  Van  Ryn 
series  with  the  Rietfontein,  assigns  to  the  latter  at 
the  same  time  a  definite  horizon  in  the  above-men- 
tioned system,  the  horizon  in  fact  which  according  to 
general  opinion  is  occupied  by  the  Main  Reef,  a  view 
that  compels  him  to  place  that  series  a  good  step 
higher  in  the  system.  It  is  in  this  manner  that  he 
would  prove  that  in  the  place  of  one  there  are  two 
important  reef-horizons  in  the  system,  a  fact  which  he 
thinks  should  provide  all  the  encouragement  neces- 
sary for  greater  and  renewed  activity  in  prospecting. 
Before  however  such  further  prospecting  is  justi- 
fied, it  has  to  be  considered  that  that  which  has 
already  been  done  leaves  small  hope  of  any  extent  of 
valuable  reef  along  a  possible  second  horizon  remain- 
ing undiscovered,  and  that  for  this  reason  the  en- 
couragement from  theoretical  considerations  must  be 
better  based  than  would  be  the  case  if  the  previous 
work  in  that  direction  had  not  been  so  thorough.  Un- 
fortunately, though  it  is  claimed  that  the  views  in  the 
treatise  under  review  are  built  upon  many  new  facts, 
these  new  facts  do  not  stand  out  clearly,  and  the  bare 
statements  consequently  carry  but  little  conviction. 

These  statements,  for  whatever  they  may  be  worth, 
Mr.  Bleloch  bases  primarily  upon  the  pronounced 
appearance  in  one  section  of  the  Central  Rand  of  an 
additional  bed  of  quartzite  between  the  Main  Reef 
series  and  the  Hospital  Hill  Quartzites,  and  he  states 
that  along  any  normal  line  of  section  the  Rietfontein 
series  and  its  overlying  reefs  occur  in  conformable 
position  overlying  the  Hospital  Hill  quartzites.  this 
being  evidenced,  according  to  him,  in  the  line  of 
section  mentioned  above,  by  the  banket  beds  on 
Langermans  Kop,  which  he  says  belong  to  the  South 
Rietfontein  series.  It  is,  however,  held  by  all  the 
geologists  who  have  studied  this  line  of  section  that 
this  additional  bed  of  quartzite  is  but  a  duplicated 
outcrop  of  the  Hospital  Hill  quartzites.  this  view 
having  first  been  presented  by  Walcot  Gibson  and 
afterward  by  Hatch  and  Corstorphine,  who  explained 
that  no  duplication  of  the  Main  Reef  series  had  oc- 
curred at  the  same  time  because  the  fault  which  was 
the  cause  of  this  disturbance  did  not  reach  that  reef 
series  but  changed  its  direction  somewhat  to  run 
parallel  with  it.     This  view  has  a^'ain  lately  been  p;  t 


2—6 


154 


THE    MINING    MAGAZINE 


forward  in  the  most  convincing  and  scholarly  manner 
by  E.  T.  Mellor  in  a  paper  read  before  the  Geological 
Society  of  South  Africa  and  entitled  '  Some  structural 
features  of  the  Witwatersrand  System  of  the  Central 
Rand  with  a  note  on  the  Rietfontein  Series.'  As  Dr. 
Mellor  is  one  of  the  geologists  on  the  staff  of  the 
Geological  Survey  and  his  paper  was  read  by  per- 
mission of  the  Minister  of  Mines,  there  seems  little 
doubt  but  that  it  indicates  what  will  likely  be  the 
official  view  of  the  question.  In  that  paper  also  Dr. 
Mellor  gives  some  facts  about  the  occurrence  of  the 
Rietfontein  series  and  that  on  Langermans  Kop,  from 
which  it  appears  more  than  likely  that  these  two 
occurrences  of  banket  are  rightly  correlated,  as  they 
had  previously  been,  with  the  Elsburg  series,  and 
that  where  they  are  now  found  they  lie  unconform- 
ably  to  the  beds  of  the  Witwatersrand  system,  in 
which  they  can  therefore  occupy  no  definite  horizon. 
Between  the  reasoning  of  the  geologists  mentioned 
and  the  affirmations  of  Mr.  Bleloch  there  can  be  no 
ground  for  hesitation  ;  the  reasoning  and  the  general 
view  will  remain  while  the  affirmations  of  Mr. 
Bleloch,  which  form  the  basis  of  his  arguments,  must 
go.  It  may  also  be  said  that  even  if  Mr.  Bleloch 's 
reading  of  the  lower  horizons  of  the  Witwatersrand 
system  had  been  correct,  the  other  evidence  based 
upon  the  identity  of  the  overlying  reefs  and  upon  the 
characteristics  of  the  two  series  themselves,  would 
remain  invincible  to  arguments  that  would  place  the 
Main  Reef  and  the  Van  Ryn  series  at  different  hori- 
zons. 

S.  J.  Truscott. 

Gold  Coast  Palaver.  By  Louis  P.  Bowler.  Cloth, 
small  octavo,  180  pages.  London;  John  Long. 
Price  2s. 

The  author  of  this  book  has  seen  much  life  in  Africa 
and  North  America  and  has  been  engaged  in  diamond- 
washing,  gold-digging,  trading,  rubber  planting,  and 
other  occupations  dear  to  the  adventurous  spirit.  He 
was  in  the  first  crowds  at  Barberton  and  Johannes- 
burg, and  was  at  Bulawayo  when  Lobengula  granted 
the  concessions  that  formed  the  foundations  of  the 
Chartered  Company.  It  is  of  interest  to  note  also 
that  he  prepared  the  first  prospector's  map  of  Mata- 
beleland.  For  the  last  eight  years  he  has  spent 
much  time  in  West  Africa,  and  this  book  gives  in  a 
pleasant  and  chatty  style  his  impressions  of  manners, 
customs,  trade  opportunities,  and  a  hundred  and  one 
other  interesting  features  of  jungle  life.  His  accounts 
of  native  superstitions,  with  conversations  in  the  ver- 
nacular, show  his  observant  mind,  and  his  descrip- 
tions of  insect  life  are  both  vivid  and  humorous. 
Though  the  book  is  not  exactly  an  authoritative  treat- 
ise, it  is  eminently  readable. 

Crystallography  and  Practical  Crystal 
Measurement.  By  A.  E.  H.  Tutton.  Cloth  oc- 
tavo, 960  pages,  with  many  illustrations.  London  ; 
Macmillan  &  Co.  Price  30s.  For  sale  by  The  Min- 
ing Magazine. 

It  is  impossible  to  do  justice  to  this  book  within  the 
limited  space  at  our  disposal  ;  even  an  enumeration  of 
the  headings  of  the  fifty-five  chapters  would  fill  one 
of  our  columns.  The  author  has  the  rare  ability  of 
making  advanced  science  seem  simple,  and  of  dis- 
cussing profound  problems  with  ease  and  dignity. 
The  consequence  is  that  a  student  or  engineer  with 
only  a  general  or  elementary  knowledge  of  the  prin- 
ciples of  mineralogy  and  optics  can  follow  the  author 
without  difficulty  and  pursue  his  studies  in  every  pos- 
sible branch  of  the  science.  Those  who  were  repelled 
years  ago  by  the  empirical  methods  of  crystallography 


will  find  the  more  recent  theories  most  attracti\'e  and 
indeed  comforting.  Incidentally  we  may  say  that  the 
author  does  valuable  service  in  presenting  clear  accounts 
of  the  theoretical  studies  of  Continental  scientists  that 
have  been  a  sealed  book  to  many  because  of  their  pub- 
lication in  only  the  German  and  Russian  languages. 
The  most  notable  are  the  researches  and  theories  of 
Von  Federow  of  St.  Petersburg.  An  interesting  sub- 
ject is  that  of  liquid  crystals,  that  is,  the  assumption 
of  definite  crystalline  shape  by  one  liquid  suspended 
in  another  ;  this  phenomenon  may  eventually  be  an 
aid  in  the  study  of  magmatic  segregation .  Other  parts 
of  the  book  of  interest  to  the  economic  geologist  are 
those  relating  to  the  optics  of  internal  reflection  of 
light,  and  to  the  detection  of  internal  strains.  These 
are  of  value  in  the  study  of  the  origin  and  history  of 
rocks,  fillings,  and  veins,  especially  as  to  their  para- 
genesis.  Werecommend  the  book  to  our  scientifically- 
minded  readers. 

Modern  Practice  in  Mining.  Vol.  IV,  Ventila- 
tion. By  R.  A.  S.  Redmayne.  Cloth  octavo,  250 
pages,  illustrated.  London:  Longmans,  Green&  Co. 
Price  6s.  6d.  For  sale  by  The  Mining  Magazine. 
In  our  issue  of  October  1909  we  gave  a  notice  of 
this  series  of  books  on  mining  prepared  by  R.  A.  S. 
Redmayne,  lately  professor  of  mining  in  Birmingham 
University  and  now  Chief  Inspector  of  Mines  for  the 
United  Kingdom.  Mining  is  a  big  subject  and  cannot 
be  adequately  covered  in  one  book.  Several  encyclo- 
pedic works  have  recently  been  issued  dealing  with  all 
branches  of  operations,  and  they  are  published  in 
many  volumes,  which  are  not  sold  separately.  Mr. 
Redmavne's  series  is  an  exception,  for  each  volume  is 
a  book  by  itself  and  is  sold  as  such  ;  for  this  reason 
they  should  be  readily  saleable.  Since  originally  re- 
ferring to  the  series  two  years  ago,  we  have  also  re- 
viewed another  volume  on  shaft-sinking.  The  third 
volume  now  issued  deals  with  ventilation,  a  subject 
which  is  receiving  increased  attention  in  metal  mines 
at  the  present  time.  The  scope  of  the  book  is  deter- 
mined by  the  application  of  ventilation  methods  to 
coal  mines  and  the  reference  to  the  requirements  of 
metalliferous  mines  is  scant.  In  fact,  Mr.  Redmayne 
contents  himself  with  two  short  extracts  from  contem- 
porary literature,  one  on  the  Comstock  taken  from  the 
paper  presented  by  G.  J.  Young  to  the  American  In- 
stitute, and  the  other  on  the  East  Rand  Proprietary  by 
Sydney  Penlerick,  read  before  the  Chemical,  Metal- 
lurgical, and  Mining  Society  of  South  Africa.  How- 
ever, as  the  book  contains  so  much  useful  information 
applicable  to  all  ventilation  problems,  it  will  be  of  ser- 
vice to  managers  of  metalliferous  mines. 

The  Mining  Industry  of  Mexico.    No.  1,  Hidalgo. 
Compiled  and  edited  by  F.  Gonzalez,  A.  Grothe, 
and  L    Salazar.     Quarto,  paper  covers,  76  pages, 
with    many    illustrations    and    working    drawings. 
Mexico  City  :  Vda  de  Bouret.     Price  2s.  6d. 
This  is  the  first  number  of  a  series  of  20  volumes 
that  has  been  undertaken,  with  the  assistance  of  the 
department  of  Fomento  of  the  Mexican  Government, 
for  the  purpose  of   supplying  reliable  first-hand  in- 
formation concerning  present  Mexican  mining  and  of 
the   prospects   of   further  expansion.     This    number 
deals  with  mines  in  the  State  of  Hidalgo  and  it  con- 
tains a  vast  amount  of   information  about  Pachuca 
and  Real  del   Alonte,  with  maps  showing  the  claims, 
topography    and  geology,  photographs,  and  plans  and 
sections  of  mines.     The  editors  are  well  known  min- 
ing engineers  and  metallurgists,  and  they  may  be  ex- 
pected to  produce  a  most  valuable  series  of  records  of 
the  Mexican  mining  industry. 


AUGUST,    1911 


155 


COMPANY   REPORTS 

Kyshtim  Corporation. — This  company  was  formed 
in  October  1908  to  acquire  the  share  capital  of  the 
Kyshtim  Mining  Works  Company  which  owns  and 
operates  iron  mines,  gold  and  copper  deposits,  and 
timber  land  in  the  Perm  government  in  the  Southern 
Ural.  It  was  promoted  by  the  Perm  Corporation. 
Details  of  the  various  interests  and  arrangements  were 
given  in  an  editorial  article  in  our  June  issue.  R. 
Gilman  Brown  is  consulting  mining  engineer,  Walter 
G.  Perkins  is  consulting  metallurgical  engineer,  H.  H. 
Knox  is  advisory  consulting  engineer,  and  Leslie 
Urquhart  is  general  manager.  H.  W.  Turner  has 
been  engaged  to  make  a  geological  examination  and 
survey  of  the  copper  deposits.  The  report  now  issued 
covers  the  year  1910.  During  that  time  89,509  tons 
of  copper  ore  averaging  3  38%  copper  was  mined 
chiefly  from  the  Koniukhoff  mine.  The  production 
was  1674  tons  of  blister  copper,  containing  2578  oz. 
gold  and  22,272  oz.  silver.  Subsequent  information 
shows  that  from  January  1  to  June  10  of  this  year  the 
production  was  1712  tons  copper.  Until  November, 
smelting  was  done  at  the  old  plant,  and  in  that  month 
the  first  new  blast-furnace  at  Karabash  started  opera- 
tions, followed  by  No.  2  in  March  of  this  year.  Two 
basic-lined  converters  have  also  been  erected.  There 
is  a  small  Siemens-Martin  reverberatory  at  Kyshtim 
to  treat  the  fine  ore  and  flue-dust,  but  it  is  now  planned 
to  build  a  new  reverberatory  at  Karabash.  The  whole 
of  the  copper  is  electrolytically  refined  on  the  spot. 
The  copper  ore  reserve  was  calculated  in  June  at 
1,500,000  tons  averaging  3^%  copper.  As  regards  the 
financial  results  for  1910  of  the  Russian  company,  the 
profit  of  the  copper  works  was  /'64,335,  of  the  iron- 
works ;^23,- 60,  of  the  timber  department  ;^37,371,  and 
in  addition,  the  sale  of  pyrite  for  sulphur  content,  in- 
come from  gold  gravel  production,  and  other  small 
items,  brought  the  total  receipts  to  ;^135,882.  Against 
this  £55,517  was  debited  for  general  expenses,  taxes, 
and  interest  on  loans  from  banks,  and  ;^38,256  was 
paid  as  interest  on  mortgages.  The  amount  paid  to 
the  credit  of  the  Kyshtim  Corporation  was  /31,579. 
The  accounts  of  the  Kyshtim  Corporation  show  re- 
ceipts /33,310,  out  of  which  ;^19,523  was  paid  as  in- 
terest on  ;^362,500  of  6%  debentures,  ;^5000  was  paid 
as  directors'  fees,  ;^2856  as  managing  director's  re- 
muneration and  office  expenses,  and  there  were  other 
expenses  reducing  the  credit  balance  to  nothing.  Dur- 
ing the  year,  ;!^12,500  of  new  debentures  were  issued, 
and  since  then  a  further  ;^37,500  have  been  issued  ;  by 
this  means  £37,750  appearing  in  the  balance-sheet  as 
loans  has  been  repaid.  The  capital  advanced  during 
the  year  to  the  Russian  company  for  the  purpose  of 
erecting  the  new  copper- smelting  plant  and  for  pros- 
pecting was  /155,760. 

Troitzk  Goldfields. — In  our  issue  of  August  last  year 
we  gave  a  resume  of  the  history  of  this  Siberian  gold 
mine  and  recorded  how,  after  early  financial  trouble, 
work  was  reorganized  by  Hooper,  Speak,  &  Feilding.  A 
new  treatment  plant  was  erected  and  much  prospecting 
work  was  done  under  the  direction  of  their  resident 
partner,  H.  C.  Bayldon.  The  new  mill  started  work 
in  August  1909  and  work  was  continuous  until  May  25 
of  this  year,  when  a  fire  broke  out  in  the  Stanley  shaft 
and  not  only  caused  the  mouth  of  the  shaft  to  collapse 
but  ruined  the  hoisting  plant,  pumps,  and  air  com- 
pressors. This  calamity  has  hastened  the  crisis  which 
was  impending  owing  to  the  inability  of  the  mine  to 
pay  its  way,  and  a  scheme  of  reorganization  has  been 
prepared  for  the  purpose  of  refunding  the  loan  of 
/58,000  advanced  by  the  parent  company,  the  Siberian 


Proprietary,  and  of  raising  /45,000  further  working 
capital  ;  104,993  priority  shares  of  £l  each  are  being 
ottered  at  par  to  shareholders,  entitling  the  holders 
to  90%  of  the  distributable  profits  each  year 
Six  months  ago,  Mr.  Bayldon  had  submitted  a 
report  suggesting  various  improvements.  Onetrouble 
was  that  suitable  labour  is  scarce  and  it  was  proposed 
to  take  steps  to  collect  a  settled  mining  population. 
Other  propositions  were  to  suspend  milling  for  a  few 
months  in  order  to  press  forward  development  work, 
and  to  provide  additional  cyanide  plant,  especially  for 
the  treatment  of  slime.  The  directors  last  month  pro- 
posed and  the  shareholders  have  approved  that  this 
new  work  shall  go  forward.  The  report  for  1910 
shows  that  Chilean  mills  treated  40,621  tons  of  ore  and 
that  8257  oz.  was  extracted  by  amalgamation,  1476  oz. 
recovered  by  cyaniding  sand,  and  469  oz.  recovered  by 
cyaniding  concentrate,  making  a  total  of  10.202  oz.. 
an  extraction  of  79%  of  the  estimated  content  of  the 
ore.  The  receipts  from  the  sale  of  gold  were  ^^42,930. 
and  the  cost,  including  interest  on  loans,  depreciation, 
and  development  redemption  was  £52,359.  The  ore 
reserve  on  December  31  was  given  at  40.400  tonsaver- 
a-ging  7^dwt.  Owing  to  the  lenticular  shape  of  the 
orebodies  it  is  not  possible  to  give  close  figures  in  the 
estimate. 

Orsk  Goldfields. — This  company  is  also  a  subsidiary 
of  the  Siberian  Proprietary,  and  we  gave  a  lengthy 
account  of  its  history  and  the  nature  of  the  business  in 
our  issue  of  August  last  year.  The  report  for  the  year 
1910  now  issued  does  not  contain  much  further  infor- 
mation. It  will  be  remembered  that  after  the  gold 
mining  properties  at  Orsk  in  Western  Siberia  had  been 
proved  valueless,  a  placer  property  was  acquired  near 
Nicolaievsk  at  the  mouth  of  the  Amur  river.  A  modern 
dredge  was  ordered  from  New  York.  Owing  to  a 
collision  outside  New  York  harbour,  the  despatch  of 
the  dredge  was  delayed  and  it  did  not  reach  Siberia 
before  the  winter  commenced  in  November  last.  Con- 
sequently it  has  had  to  remain  idle  at  Vladivostok  har- 
bour during  the  winter.  It  is  now  being  erected  and 
should  be  at  work  before  the  end  of  the  summer,  under 
the  superintendence  of  C.  H.  Munro.  As  already 
recorded  in  the  Magazine,  the  delay  in  getting  the 
dredge  to  work  caused  financial  embarrassment  and  it 
was  necessary  in  January  last  to  offer  100,000  priority 
shares  of  £l  each  to  the  shareholders  ;  of  these  80.000 
were  underwritten  by  the  Siberian  Proprietary. 

Burma  Mines. — This  company  was  formed  in  I'^Oo 
to  acquire  ancient  silver-lead  mines  and  slag  piles  at 
Bawdwin,  Upper  Burma,  not  far  from  the  Chinese 
frontier.  Bewick,  Moreing  &  Co.  are  the  general  man- 
agers, F.  A.  Govett  is  chairman,  and  H.  C.  Hoover  is 
on  the  board.  The  mines  had  presumably  been  worked 
for  silver  only  in  earlier  days,  judging  bv  the  fact  that 
enormous  amounts  of  slag  averaging  45%  lead  are 
found  scattered  around  on  the  surface.  The  Chinese 
miners  had  confined  their  attention  chiefly  to  the  car- 
bonates, though  there  is  evidence  that  they  also  treated 
the  sulphides.  The  company  has  been  collecting  the 
slag  and  shipping  it  to  Mandalay  to  be  smelted.  This 
involves  high  cost  of  transport,  and  in  other  ways  the 
circumstances  have  militated  against  financial  success. 
A  year  ago  we  reported  that  the  results  for  1909  had 
left  the  company  with  an  adverse  balance  of  /I23.20I, 
and  that  a  drastic  reorganization  and  writing  down  of 
lost  capital  was  necessary.  The  capital  was  reduced 
from  /355,589  in  £l  shares  to  £7S.0\\,  divided  into 
312. 046 shares  of  4s.  each,  of  which  286. 5CS  carry  a  lia- 
bility of  2s.  There  are  also  ;{;i49,188  first  debentures 
and  i;"34.130  interest  accrued,  and  ;£30.4 10  second  de- 
bentures. The  report  for  1910  shows  that  28,772  tonsof 


156 


THE    MINING    MAGAZINE 


slag,  averaging  46%  lead  and  ISoz.  silver,  was  smelt- 
ed, together  with  500  tons  of  ore  from  Bawd  win  and  3503 
tons  of  purchased  ore.  The  receipts  from  the  sale  of 
the  metals  were  /160,918,  less  ;^31,338  freight  and 
realization  charges.  The  cost  of  transport  from  the 
mine  to  the  smelter  was  no  less  than  ;^43,007.  After 
payment  of  all  expenses  and  making  allowance  for 
depreciation,  the  balance  of  profit  was  /9034.  The 
directors  mention  that  the  slag  piles  are  limited  in  ex- 
tent and  that  they  will  be  exhaused  in  about  18  months 
from  the  present  time.  Active  prospecting  and  develop- 
ment work  is  therefore  being  prosecuted  at  the  mines. 
An  important  discovery  has  been  made  of  a  lode  6  ft. 
wide,  assaying  8%  lead,  5%  copper,  33%  zinc,  and  19 
oz.  silver.  At  the  meetings  of  shareholders  held  last 
month  various  resolutions  were  passed  consolidating 
the  debentures.  It  was  announced  that  more  favour- 
able terms  of  transport  by  railway  had  been  obtained, 
and  that  at  the  present  time  it  is  impossible  to  proceed 
with  any  scheme  of  transferring  the  smelter  to  the 
mine. 

Burma  Ruby  Mines. — This  company  was  floated  22 
years  ago  by  the  Rothschilds  to  consolidate  the  ruby 
and  sapphire  mines  at  Mogok,  Burma.  The  expecta- 
tions of  big  profits  were  never  realized,  and  the  share- 
holders have  received  small  returns  and  have  suffered 
loss  of  capital.  More  money  was  required  than  was 
expected,  for  the  provision  of  water-supply  and  for 
plant.  The  rent  and  royalty  demanded  by  the  Indian 
Government  have  been  oppressive,  and  of  recent  years 
the  unpopularity  of  corundum  and  spinel  stones  has 
seriously  checked  the  income  from  sales.  Not  only  is 
the  demand  in  Europe  small,  but  the  price  has  dropped 
50%  as  compared  with  10  years  ago.  Most  of  the 
sales  are  now  made  locally  and  not  in  the  London  and 
European  markets.  The  directors  do  not  mention  the 
subject,  but  no  doubt  the  production  of  artificial  rubies 
and  sapphires  by  the  process  described  in  our  June 
issue  will  seriously  affect  the  market  for  the  natural 
stones.  The  report  for  the  year  ended  February  28 
shows  that  1,466,136  loads  of  earth  were  washed  at  a 
cost  of  7Jd.  per  load,  and  the  sales  from  stock  were 
;if^l2,666  in  London  and  /3S,522  in  Burma,  a  total  of 
;f51,189.  The  stock  on  hand  on  February  28  was 
valued  at  /56,809.  The  profit  for  the  year  was  /1090, 
and  the  royalty  paid  to  the  Indian  Government  was 
/8852.  The  Government  has  remitted  arrears  of 
royalty  amounting  to  ;^4713,  but  declines  to  forego 
/^19,228  unpaid  rent  and  royalty,  though  it  takes  no 
steps  to  press  for  payment. 

Associated  Gold  Mines  of  Western  Australia. — It 
will  be  remembered  that  this  company,  owning  the 
Australia  leases  at  Kalgoorlie,  arrived  at  a  critical 
period  of  its  history  eighteen  months  ago,  when  it  was 
discovered  that  the  sampling  of  the  reserve  was  wrong, 
the  content  being  found  to  be  nearer  6  dwt.  than  10 
dwt.,  as  previously  supposed.  Up  to  that  time  the 
mine  had  done  well  and  had  yielded  gold  worth 
/2, 893, 226  from  1,037,955  tons  of  ore.  TheconsultinL; 
engineer,  E.  H.  Liveing,  made  suggestions  a  year  ago 
for  future  work  ;  and  since  then  the  manager,  George 
M.  Roberts,  has  resigned,  and  Duncan  F.  McAulay 
has  been  appointed  to  the  position.  The  report  for 
the  year  ended  March  31,  1911,  now  issued,  reflects 
the  present  position,  for  though  a  profit  of  /22,897 
was  made,  the  whole  of  this  and  more  has  been  allo- 
cated to  the  cost  of  development  and  diamond-drilling, 
so  that  for  the  first  time  since  1903  the  shareholders 
are  without  a  dividend.  During  the  year  105,238  tons 
of  ore  was  sent  to  the  mill,  where  34,499  oz.  gold 
worth  /146,624  was  recovered,  or  27s.  lOd.  per  ton. 
The  total  expenses  were  ;^123,786,  in  addition  to  which 


/3923  has  been  charged  for  diamond-drilling  and 
224,761  for  development  work.  The  engineers  do  not 
give  any  estimate  of  ore  reserves,  though  they  consider 
that  there  is  sufficient  to  keep  the  mill  going  for  three 
years.  Since  the  end  of  the  financial  year,  conditions 
have  improved  as,  owing  to  the  provision  of  additional 
plant,  it  has  been  possible  to  mine  and  treat  more  ore. 
The  June  figures  were  :  ore  10,041  tons  and  yield 
/15,372. 

Broken  Hill  Block  14. — This  is  a  small  mine  situ- 
ated between  the  Broken    Hill  Proprietary  and    the 
British  Broken  Hill,  and  has  been  worked  since  1889. 
For  some  years  past  the  only  work  done  has  been  the 
removal  of   carbonate  ore  left  behind   in   the  upper 
levels.     In  1905  the  sulphide  tailing  heaps  were  sold 
to  the  Zinc  Corporation,  and  during  1910  some  of  the 
low  grade  sulphide  was  mined  for  the  benefit  of  the 
Murex  Company,  whose  engineers  were  testing  this 
process  on  the  spot.     The  report  for  the  six  months 
ended  March  31  shows  that  10,753  tons  of  carbonate 
ore  averaging  31%  lead  and  18  oz.  silver  was  mined 
and  shipped.     This  ore  was  fully  3  oz.  richer  in  silver 
than  any  that  has  been  recently  mined.     The  cost  of 
mining  this  ore  was  22s.  Id.  per  ton  and  the  income 
from  its  sale  was  /26,241.      It  has  been  possible  to 
distribute  /1500  on  the  preference  shares  and  /lO.OOO 
on  the  ordinary  shares.     As  regards  the  carbonate  ore 
supply,  the  engineer,  H.  Voss  Smith,  reports  that  new 
bodies  are  being  continually   discovered  in   the  old 
workings,   and   though   no  definite  estimate  can    be 
made,   the  probability  is,  judging  by  the  extent  of 
ground  still  to  be   tested,  that  an  income  from  this 
source  may  be  expected  for  a  considerable  time.     As 
regards  the  Murex  process  the  directors  announce  that 
it  has  not  been  found  applicable  to  the  ore.     Alto- 
gether 1521  tons  of  sulphide  ore  was  mined  for  the 
purpose  of  testing  the  process,  averaging   12%   lead, 
8f  %  zinc,  and9^oz.  silver.   In  thelastcontinuousrun  of 
theplant661  tons  of  ore  was  treated  assaying  12%  lead, 
8J%  zinc,  and  8j?  oz.  silver,  and  1856  tons  of  concen- 
trate was  produced,  assaying  31%  lead,  21%  zinc,  and 
19§  oz.  silver,  being  an  extraction  of  about  72%  of  the 
lead  and  zinc  and  64%  of  the  silver.     The  other  part 
of  the  Murex  process,  namely,  the  separation  of  the 
two  sulphides,  has  not  been  a  success  so  far,  but  ex- 
periments are  still  being  made.     The  directors  have 
therefore  decided  to  take  other  steps  for  the  beneficia- 
tion  of  the  large  amount  of  sulphides  still  in  the  mine, 
the  proved  reserve  containing  about  220,000  tons,  and 
George  Weir,  the  manager  of  the  North  Broken  Hill, 
has  been  asked  to  examine  the  mine  and  the  mill,  and 
to  make  suggestions  as  to  the  best  course  to  pursue. 

Broken  Hill  Block  10. — Operations  of  this  mine 
during  the  half-year  ended  March  31  have  been  hin- 
dered by  a  shortness  of  skilled  labour  and  only  48,754 
tons  of  ore  was  mined  and  milled  as  compared  with 
53,025  tons  during  the  previous  half-year.  A  year  ago 
a  break  in  the  work  was  caused  by  the  coal  strike. 
Since  the  beginning  of  the  present  year  the  wages 
have  been  considerably  higher,  but  the  total  cost  will 
not  be  appreciably  raised,  because  many  labour-saving 
devices  have  been  installed,  especially  in  the  hauling 
gear  in  the  mine  and  in  the  method  of  transporting 
the  material  at  the  concentrating  plant.  The  asay  of 
the  ore  treated  during  the  half-year  was  12^%  lead, 
15S%  zinc,  and  12ioz.  silver;  6477*  tons  of  lead  con- 
centrate was  produced  assaying  62§%  lead,  6A%  zinc, 
and  37i  oz.  silver.  As  regards  the  zinc  tailing,  it  will 
be  remembered  that  a  year  ago  an  Elmore  plant  was 
erected,  but  that  within  a  few  months  it  was  dis- 
mantled, because  the  directors  considered  that  the 
more  profitable  policy  would  be  to  sell  the  tailing  to 


AUGUST,   1911 


157 


the  De  Bavay  Company.  Accordingly  42,084  tons  has 
been  delivered  in  this  way  during  the  half-year  at  a 
price  of  5s.  3d.  per  ton  less  2J%  commission  ;  the 
assay  was  44%  lead,  159%  zinc,  and  7  7  oz.  silver. 
The  company  still  receives  an  income  from  the  sale  of 
accumulated  tailing,  and  /64,978  has  yet  to  be  received 
from  this  source.  The  accounts  for  the  half-year  show 
receipts  /50,589  from  the  sale  of  current  tailing,  and 
there  are  credits  amounting  to  /35,932  on  account  of 
old  tailing.  The  expenditure  was  /69,345,  including 
taxes  and  allowance  for  depreciation  ;  ;f  10,000  was 
paid  as  dividend,  being  at  the  rate  of  1%  on  the  capi- 
tal £1,000,000,  and  the  remainder  carried  forward. 
The  manager,  V.  F.  Stanley  Low,  gives  details  of 
development  work  done  during  the  period  on  the 
1615  ft.  and  1715  ft.  levels.  At  the  former  the  ore- 
body  was  found  to  be  narrow  and  it  eventually  nearly 
disappeared.  The  contents  of  the  ore  varied  con- 
siderably, but  the  average  was  fairly  good.  At  the 
latter  level  the  orebody  is  20  ft.  wide,  with  a  rather 
low  average  assay.  As  the  lode  is  similar  in  appear- 
ance to  what  it  was  on  the  615  ft.,  815  ft.,  and  915  ft. 
levels,  there  is  encouragement  to  expect  better  quality 
ore  as  the  work  continues.  At  the  two  other  proper- 
ties recently  acquired,  namely,  the  Rising  Sun  and  the 
Comstock,  disappointing  results  have  been  obtained. 
No  more  prospecting  is  to  be  done  at  the  latter,  and  it 
is  now  in  the  hands  of  tributers. 

Consolidated  Gold  Fields  of  New  Zealand. — This 
company  was  formed  in  1896  to  acquire  properties  in 
the  Reefton  district  of  New  Zealand  from  David 
Ziman.  The  chief  mine  operated  by  the  company  is 
the  Wealth  of  Nations  ;  the  Progress  and  Blackwater 
mines  were  floated  as  separate  subsidiaries  in  which  the 
•company  holds  a  large  proportion  of  the  share  capital. 
The  report  for  the  year  1910  now  issued  shows  that  the 
Wealth  of  Nations  mine  continues  to  open  up  well 
and  in  June  of  this  year  the  mill  was  increased  from 
20  to  35  stamps  During  1910,  21,363  tons  of  ore  was 
treated  in  the  20  stamps,  tube-mill,  and  cyanide  plant, 
and  gold  worth  ;^36,3S5  was  recovered.  The  working 
cost  was  ;^19,704.  On  December  31  the  ore  reserve 
was  estimated  at  25,944  tons,  averaging  49s.  per  ton. 
The  Golden  Fleece  alluvial  property  belonging  to  the 
company  was  worked  by  tributers  and  the  company's 
share  of  the  yield  was  worth  ^2156.  The  dividends 
received  from  the  two  above-named  subsidiaries, 
together  with  other  receipts,  brought  an  income 
•of  ;^22,696,  making  the  total  income  ;^61,169.  The 
total  cost  at  the  mine  and  in  London  was  ;^23,284, 
and  /12,160  was  written  off  for  depreciation.  The 
dividend  absorbed  ;if 24, 237  being  at  rate  of  10%  on  the 
issued  capital.  The  company  also  owns  interests  in 
the  Kotuku  Oilfields  Syndicate  and  in  the  New  Zealand 
Crown  Mines.  In  September  of  last  year  the  manager, 
E.  W.  Spencer,  resigned,  and  he  has  since  been  suc- 
ceeded by  A.  Winter  Evans,  recently  assistant  man- 
ager of  the  Simmer  Deep. 

Progress  Mines. — As  recorded  in  the  preceding  para- 
graph this  company  is  a  subsidiary  of  the  Consolidated 
Gold  Fields  of  New  Zealand  and  was  floated  in  1896. 
In  our  issue  of  October  last  year  we  mentioned  that  the 
mine  has  not  been  yielding  as  much  ore  during  the 
last  two  or  three  years  as  formerly  and  the  whole  of 
the  65  stamps  are  not  always  employed.  The  develop- 
ments during  1910  were  more  satisfactory  than  during 
1909.  The  tonnage  treated  was  50,202  as  compared 
with  35,414,  and  the  yield  was  worth  /73,513  as  com- 
pared with  £52,050.  At  the  same  time  the  working 
cost  was  ;^69,389  as  compared  with  /46,423.  In  ad- 
dition general  expenses  absorbed  ;^5623,  taxes  ;^1944,  de- 
preciation /4404,  and  development  redemption  ;^5373. 


The  company  has  a  large  holding  in  Blackwater  shares 
from  which  a  dividend  of  /13,019  was  received.  The 
net  financial  result  for  the  year  was  that  the  income 
and  expenditure  about  balanced,  as  was  the  case  in 
1909,  but  a  dividend  of  /10,312  has  been  distributed 
at  the  rate  of  3|%  out  of  the  balance  brought  forward 
from  1908,  a  similar  amount  having  been  distributed 
a  year  ago  from  the  same  source. 

Blackwater  Mines.— When  the  mines  worked  by 
the  Consolidated  Gold  Fields  of  New  Zealand  and  the 
Progress  Mines  began  to  give  disappointing  results, 
the  two  companies  acquired  the  Blackwater  property 
and  floated  it  as  a  separate  company  in  1906.  The 
results  obtained  have  been  most  encouraging  and  the 
profits  go  far  toward  providing  dividends  for  the 
parent  companies.  Milling  was  commenced  in  .\ugust 
1908  and  the  first  dividend  was  paid  out  of  the  profits 
for  1909.  The  report  for  1910  now  issued  records  that 
39,192  tons  of  ore  was  treated  yielding  bullion  worth 
;^91,253.  The  total  revenue  was  ;^92,180,  and  the  ex- 
penses ^^36,708  ;  taxes  absorbed  /3370,  and  /1844  was 
allowed  for  depreciation  of  plant,  while  /10,000  was 
written  off  development  account.  The  divisible  balance 
of  profit  was  /39,298  and  /37,498  was  distributed  as 
dividend,  being  at  the  rate  of  15%.  Owing  to  the 
drought  during  three  or  four  months  of  each  year,  it 
has  been  found  advisable  to  supplement  the  Pelton 
water-power  installation  with  suction  gas  plant.  .\n- 
other  recent  improvement  has  been  the  addition  of 
Wilfleys  for  the  purpose  of  removing  sulphides  after 
stamp-milling  and  before  cyaniding.  An  extensive 
scheme  of  development  is  in  hand  so  that  a  full  esti- 
mate of  ore  reserves  is  not  yet  possible.  The  proved 
ore  is  reported  at  69,000  tons,  but  the  resources  of  the 
mine  are  obviously  much  greater,  judging  by  current 
development  work.  The  veins  vary  considerably  in 
width  and  content,  and  their  value  is  not  easily  com- 
puted. 

Hampden  Cloncurry. — This  company  was  formed 
in  1906  for  the  purpose  of  developing  the  Hampden 
and  Duchess  copper  properties  situated  near  Clon- 
curry, North  Queensland.  It  was  reconstructed  in 
1909,  and  last  year  ^100,000  of  6J%  debentures  were 
created  and  /30,000  subscribed.  The  head  office  is 
in  Melbourne.  W.  Knox,  H.  H.  Schlapp,  and  W. 
L.  Baillieu  are  on  the  board,  and  Erie  Huntley  is 
general  manager.  The  present  report  covers  tiie  iialf- 
year  ended  February  28,  but  later  information  is 
added.  Development  work  has  been  actively  prose- 
cuted and  the  ore  reserves  increased.  No  ore  has  ever 
been  shipped,  as  it  has  always  been  intended  to  treat 
everything  on  the  spot.  The  ore  reserves  at  the  two 
mines  are  reported  at  228,300  tons,  averaging  nearly 
10%  copper,  and  the  prospects  for  lurtiier  develop- 
ments and  discoveries  are  excellent.  .\  smelter  hav- 
ing a  capacity  of  125  tons  per  day  has  been  erected, 
and  it  started  operations  at  the  beginning  of  May. 
Another  furnace  is  to  be  provided,  as  also  is  a  con- 
verter plant. 

Willoughby's  Consolidated. — This  company  was 
formed  in  1894  to  consolidate  various  land  and  mining 
interests  in  Southern  Rhodesia  owned  by  Sir  John 
Willoughby  and  others.  Sir  John  is  still  one  of  the 
managing  directors  and  the  control  is  witii  the  British 
South  Africa  Company.  Until  1910  no  profit  was 
made  and  for  that  year  5%  was  paid.  Capital  has 
been  subscribed  at  various  times,  and  during  1910, 
205,054  shares  of  10s.  each  were  sold.  Since  the  end 
of  the  year  further  shares  have  been  issued  in  part  pay- 
ment for  property  belonging  to  the  Matabele  Central 
Estates  Co.,  thus  bringing  up  the  issued  capital  to 
1,267,745  shares  of  10s.  each,  equal  to  /633,872.     In 


158 


THE    MINING    MAGAZINE 


addition  there  are  ;^72,300  debentures  outstanding. 
The  company  operates  or  leases  a  number  of  gold 
mines,  of  which  Queen's,  Eileen  Alannah,  and  Eiffel 
Blue  are  the  most  important.  The  first  named  was 
floated  as  a  separate  company  in  December,  and  the 
Eileen  Alannah  was  taken  over  from  the  tributers  in 
November.  The  gold  produced  from  these  and  other 
properties  during  1910  was  worth  ;^119,908,  extracted 
from  65,347  tons  ;  of  this  /48,462  was  obtained  from 
the  mines  worked  by  the  company,  of  which  /'13,133 
was  profit,  while  /10,112  was  received  as  royalty  from 
the  mines  leased  to  tributers.  The  accounts  for  1910 
show  also  profits  of  ;^72,960  derived  from  the  sale  of 
investments,  and  /30,556  was  revenue  derived  from 
land  and  other  sources.  The  total  receipts  were 
/170,608  and  the  profit  was  /100,029,  out  of  which 
/31,695  has  been  distributed  as  dividend  and  the  rest 
carried  forward.  The  company  continues  to  own  in- 
terests in  subsidiaries,  of  which  the  Surprise  and  the 
Gaika  are  the  most  important.  The  Arizona  claims 
adjoining  the  Eileen  Alannah  have  been  acquired  and 
the  two  properties  are  to  be  floated  as  a  separate  com- 
pany shortly. 

Thistle-Etna. — This  company  was  formed  at  the  end 
of  1908  for  the  purpose  of  acquiring  the  Etna  gold 
mine  in  the  Hartley  district  of  Rhodesia,  together  with 
the  Thistle  and  six  other  properties.  It  belongs  to  the 
Rhodesia  Exploration  &  Development  Co.  group  ; 
Hans  Sauer  is  chairman,  H.  Ewer  Jones  is  consulting 
engineer,  and  M.  Eaton  is  manager.  The  metallurgical 
equipment  consists  of  Chilean  mills  and  cyanide  plant, 
and  operations  were  started  in  August  1908.  The  re- 
port for  1910  shows  that  37,261  tons  drawn  from  the 
Etna  and  Thistle  mines  was  treated  and  yielded  8077 
oz.  in  the  mill  and  2256  oz.  by  cyanide,  a  total  of 
10,333  oz.  valued  at  ;^43,968,  or  23s.  7d.  per  ton.  The 
expenses  in  Rhodesia  and  London,  together  with  al- 
lowance for  depreciation,  were  /42,582.  At  the  Etna 
mine  four  levels  have  been  opened  ;  at  the  first  three 
the  length  of  the  profitable  lode  averages  900  ft.,  the 
width  is  about  2h  ft.  and  the  average  content  is  9  dwt. 
Not  much  work  has  as  yet  been  done  on  the  fourth 
level,  but  the  content  of  such  ore  as  has  been  proved 
is  of  higher  grade,  averaging  11  dwt.  The  lode  is 
flat,  the  dip  being  26°,  and  sinking  by  the  inclined 
shaft  is  not  convenient.  It  is  intended  therefore  to 
commence  a  vertical  shaft  calculated  to  strike  the  lode 
at  620  ft.  vertical  or  1400  ft.  along  the  dip,  that  is 
850  ft.  lower  than  the  fourth  level.  Mr.  Jones  has 
matured  plans  for  continuing  sinking  at  the  Thistle 
and  for  prospecting  and  developing  the  other  six  pro- 
perties. For  the  purpose  of  providing  the  necessary 
funds,  the  issued  capital  has  been  increased  from 
/65,000  to  ;f90,000  by  the  sale  of  25,000  shares  at 
par,  and  the  allottees  have  been  granted  an  option 
until  the  end  of  1912  to  purchase  at  par  the  remainder 
of  the  authorized  capital,  /35,000. 

Antelope. — This  company  was  formed  in  November 
1908  to  acquire  gold  mining  claims  in  the  West 
Gwanda  district  of  Rhodesia,  about  60  miles  south  of 
Bulawayo.  It  belongs  to  the  Rhodesia  Exploration 
&  Development  Co.  group  and  a  large  part  of  the 
working  capital  was  guaranteed  by  Sir  Abe  Bailey. 
Under  the  direction  of  H.  Ewer  Jones,  extensive  de- 
velopment work  has  been  done,  and  the  erection  of 
extraction  plant  was  properly  postponed  until  the  lode 
was  fully  proved.  The  report  now  issued  covers  the 
year  1910  and  shows  that  the  ore  found  in  the  lowest 
or  8th  level,  720  ft.  vertically  below  the  surface,  is  of 
higher  grade  than  that  in  the  upper  levels,  the  average 
assay  being  17  dwt.  over  a  width  of  6^  ft.  The  indi- 
cations are  that  the  average  value  of  the  ore  reserve 


will  be  thereby  substantially  increased.  Down  to  the 
5th  level  the  ore  reserve  was  calculated  on  December 
31  at  55,000  tons  averaging  10  dwt.  The  company  has 
plent}'  of  working  capital  and  is  not  overloaded  with 
promoter's  shares.  The  issued  capital  is  /^225,548  of 
which  £70,250  in  shares  was  paid  to  the  vendors,  the 
Rhodesia  Exploration  &  Development  Co.,  and 
;^155,298  subscribed  in  cash.  In  the  balance  sheet 
for  December  31  last  the  cash  resources  figure  at 
/134,643,  so  that  the  company  is  well  able  to  prose- 
cute development  and  erect  a  suitable  metallurgical 
outfit. 

Wanderer. — This  company  was  formed  in  1899  to 
acquire  the  Wanderer,  Ashton,  and  other  gold  pro- 
perties in  the  Selukwe  district  of  Rhodesia,  and  pro- 
duction commenced  in  1902.  During  the  years  1903 
to  1906  the  average  output  was  25,000  oz.  per  year, 
but  subsequently  the  grade  became  very  low.  In  July 
1909  the  company  was  reconstructed  in  order  to  pro- 
vide additional  capital  and  to  purchase  the  Camper- 
down  property  near-by.  The  consulting  engineers  are 
Percy  Tarbutt  &  Co  ,  and  James  B.  Little  is  the 
manager.  The  report  now  issued  covers  the  year  ended 
April  30.  This  shows  that  the  aerial  ropeway  to  the 
Camperdown  was  completed  in  July  1910,  and  from 
that  time  onward  ore  was  delivered  to  the  Wanderer 
mill.  The  total  ore  treated  during  the  year  was 
195,234  tons,  the  highest  figure  yet  recorded  ;  of  this 
108,902  tons  came  from  the  Camperdown  and  the  re- 
mainder from  the  Ashton.  The  average  assay-value 
was  309  dwt.  per  ton,  as  compared  with  only  1*76 
dwt.  the  year  before.  The  metallurgical  process  con- 
sists of  crushing  in  rolls  and  direct  cyaniding.  The 
yield  was  22,711  oz.  valued  at  /96,446,  a  recovery  of 
235  dwt.  per  ton,  compared  with  138  dwt.  per  ton 
the  year  before.  The  profit  for  the  year,  after  allow- 
ing ;f  10,036  for  development  redemption,  was  ;^15,190. 
As  the  year  commenced  with  a  debit  balance  of 
/14,609,  the  balance  of  profit  on  April  30  was  reduced 
to  /581.  During  the  year,  6329  ft.  of  development 
work  was  done,  and  on  April  30  the  ore  reserve  at  all 
the  properties  was  estimated  at  424,195  tons.  As  the 
mines  are  fully  equipped  and  little  further  expenditure 
on  plant  is  required,  more  money  will  now  be  spent  on 
development  work.  It  will  be  seen  from  the  figures 
given  above  that  the  rate  of  extraction  is  not  high  ; 
experiments  are  being  actively  conducted  with  a  view 
of  increasing  the  efficiency  of  the  plant.  The  direc- 
tors speak  hopefully  of  the  future  of  the  company,  and 
probably  a  dividend  will  be  earned  during  the  current 
year. 

Eldorado. — The  Eldorado  Banket  &  Gold  Mining 
Co.  was  floated  in  1906  by  the  Rhodesia  Exploration  & 
Development  Co.  to  acquire  a  developed  gold  mine 
situated  to  the  north  of  Salisbury  and  Hartley,  Rho- 
desia. The  ore  is  refractory  and  the  plant  consists  of 
20  stamps,  2  Chilean  mills,  8  grinding  pans,  and  cya- 
nide plant.  Hans  Sauer  is  chairman  of  the  company, 
H.  Ewer  Jones  is  consulting  engineer,  and  H.  Stephan 
is  mine  manager.  The  capital  is  ;^300,000,  and  the 
dividends  paid  so  far  have  totalled  75%.  The  report 
for  the  year  ended  March  31  shows  that  82,802  tonswas 
mined  and  milled,  yielding  38,508  oz.  by  amalgamation 
and  9756  oz.  by  cyanide,  or  a  total  of  48,264  oz.  worth 
/205,355,  being  an  extraction  of  llgdwt.or  49s.  7d.  per 
ton,  and  arecovery  of  94%.  The  profit,  after  allowance 
for  depreciation,  was  /92,742,  out  of  which  ^90,000 
was  distributed  as  dividend,  being  at  the  rate  of  30%, 
and  /3000  was  paid  to  directors  as  their  percentage  of 
profit.  During  the  year  3003  ft.  of  development  work 
was  done,  and  on  March  31  the  reserve  was  estimated 
at  179,343  tons  down  to  the  7th  level,  averaging  16"5 


AUGUST,    1911 


159 


dwt.  The  developments  on  the  7th  level  have  been 
excellent.  Mr.  Jones  reports  that  the  lode  averages 
21  dwt.  across  6  ft.  for  a  length  of  549  ft.  The  shaft 
has  been  sunk  to  a  further  depth  in  order  that  the  8th 
and  9th  levels  may  be  opened  up  without  delay.  Cable 
advice  shows  that  where  the  cross-cut  on  the  8th  level 
has  intersected  the  lode  the  ore  averages  5  oz.  per  ton 
over  6  ft. 

Naraguta  Tin. — This  company  was  formed  in  Janu- 
ary 1910  for  the  purpose  of  acquiring  tin  gravel  pro- 
perties in  the  province  of  Bauchi,  Northern  Nigeria, 
and  is  a  subsidiary  of  the  Champion  Gold  Reefs  of 
West  Africa.  C.  G.  Lush  is  consulting  engineer,  and 
F.  O'D.  Bourke  is  manager  The  report  now  issued 
covers  14  months  ending  March  31,  and  shows  that 
551  tons  of  tin  concentrate  was  won  from  10  acres  of 


vided  out  of  the  balance  /1967  brought  forward  from 
the  previous  half-year.  The  equipment  of  the  new 
Sara's  shaft  with  pumps  and  haulage-gear  has  been 
completed  down  to  the  present  sump,  and  sinking  will 
be  resumed  shortly.  The  development  covered  1691 
ft.  or  1  ft.  for  every  46  tons  of  ore  hoisted.  The  work 
on  or  near  the  adit  level  has  proved  satisfactory  and 
a  lode  averaging  20  in.  wide  and  containing  33  lb.  of 
recoverable  black  tin  per  ton  has  been  followed  for 
384  ft.  The  prospects  at  the  Gooninnis  sett  recently 
acquired  are  not  particularly  hopeful.  In  future  much 
more  ore  will  be  drawn  from  the  Sara's  section. 

Arizona  Copper. — This  company,  with  headquar- 
ters in  Edinburgh,  owns  the  Longfellow  and  Metcalf 
groups  of  copper  mines,  a  smelter  at  Clifton,  Arizona, 
aud  a  railway  serving  the  district.     The  usual  haU- 


HEADQEAR    AT    SARA'S    SHAFT,    WHEAL    KITTY. 


land  by  sluicing  and  calabashing.  The  sale  of  this 
produce  brought  an  income  of  ;^62,603,  and  after 
paying  all  expenses,  including  taxes,  there  was  a  pro- 
fit of  ^27,161.  Out  of  this,  /17,500  has  been  distri- 
buted as  dividend,  being  at  the  rate  of  10%.  The 
property  bought  by  the  company  on  flotation  is  5 
square  miles  in  extent,  and  other  tracts  are  now  being 
acquired. 

Wheal  Kitty  &  Penhalls. — The  half-yearly  report 
of  this  company  operating  the  Wheal  Kitty  tin  mine  at 
St.  Agnes,  Cornwall,  under  the  direction  of  J.  H. 
Collins,  covers  the  first  six  months  of  1911,  and  shows 
that  this  small  mine  is  still  giving  satisfactory  results. 
The  policy  has  been  to  mine  lower  grade  ore  during 
the  period  of  higher  prices  of  the  metal.  The  ore 
raised  and  treated  during  the  period  was  7816  tons 
yielding  98  tons  of  concentrate  which  sold  for  /1 1 ,602, 
as  compared  with  7636  tons,  110  tons,  and  /1 1,091 
respectively  during  the  previous  six  months.  The 
price  obtained  averaged  /1 19  per  ton  as  compared 
with  ;^100.  The  profit  was  /1875,  out  of  which 
/1492  was  written  off  for  depreciation  and  for  shaft- 
sinking.  Dividends  at  the  rate  of  10%  per  annum  on 
the  preference  shares  and  3%  per  annum  on  the  or- 
dinary shares  absorbed  /841,  part  of  which  was  pro- 


yearly  interim  report  has  been  issued,  covering  the 
work  done  during  the  six  months  October  to  March. 
The  amount  of  ore  raised  was  395,577  tons,  and 
80,643  tons  of  ore  and  concentrate  was  smelted,  yield- 
ing 9133  short  tons  in  the  form  of  blister  and  sul- 
phate. The  yield  was  2'31%  of  copper  per  ton.  The 
income  from  the  sale  was  /460,780,  and  the  profit  was 
;^11 1,150  which,  together  with  /36,420  profit  on  the 
railway  and  other  holdings,  brought  the  profit  to 
/147,570.  Out  of  this  /lO.lH  has  been  paid  as  in- 
come tax,  /1969  as  interest  on  debentures,  ;^1 2.265 as 
dividend  on  preference  shares,  and  ;^94.993as  dividend 
on  the  ordinary  share  capital /379, 974,  or  25%  for  tiie 
half-year.  Though  the  price  of  copper  was  lower, 
the  profits  have  not  been  appreciably  affected  and 
stand  at  about  the  same  as  during  the  year  ended 
September  30  last.  In  addition  to  expenses  charged 
to  revenue  account,  /33, 571  has  been  spent  on  new 
concentrating  plant  and  on  the  new  shaft,  and  this 
has  been  charged  to  capital.  The  directors  report  that 
after  consultation  on  the  spot  with  L.  D.  Ricketts.  who 
is  now  their  consulting  engineer,  they  have  decided  to 
proceed  with  the  erection  of  a  new  smelter  and  power- 
plant.  James  Colquhoun,  the  former  manager,  has 
suggested  a  different  site  from  that  proposed  by  Mr. 


160 


THE    MINING    MAGAZINE 


Ricketts,  and  the  work  will  not  be  commenced  until 
the  latter  has  investigated  the  former's  proposition. 

Treasury  Gold. — This  is  a  small  mine  on  the  out- 
crop in  the  central  part  of  the  Rand  and  is  situated  be- 
tween the  Geldenhuis  and  the  Jumpers.  During  re- 
cent years  it  has  been  under  Neumann  control.  Divi- 
dends were  first  paid  in  1892,  and  continued  until  1905, 
since  which  time  any  available  surplus  has  been  accu- 
mulated. A  year  ago  it  was  found  that  the  mine  was 
approaching  exhaustion  and  that  it  was  not  possible  to 
extract  the  remaining  ore  at  the  rate  required  to  keep 
the  mill  fully  occupied.  It  happened  that  the  adjoin- 
ing mine,  the  Jumpers,  which  belongs  to  the  Wernher- 
Beit-Eckstein  group,  was  in  almost  exactly  the  same 
position,  and  it  was  decided  to  make  a  working  arrange- 
ment between  the  two  companies  whereby  from  No- 
vember 1  last  the  Jumpers  should  take  over  the  man- 
agement of  the  Treasury  and  pay  to  the  latter  one 
third  of  the  profits  derived  from  the  joint  working  of 
the  two  mines.  In  this  way  it  has  been  found  pos- 
sible to  keep  the  Jumpers  mill  fully  employed,  and  to 
extract  much  of  the  ore  left  in  both  mines  in  shaft 
and  boundary  pillars,  etc.  The  report  of  the  Treasury 
now  issued  covers  the  year  ended  March  31.  For  the 
first  seven  months  of  the  year,  86,753  tons  was  raised, 
and  after  the  removal  of  26%  waste,  64,230  tons  went 
to  the  mill,  where  19,906  oz.  worth  ;^83, 398  was  ex- 
tracted. The  working  profit  was  /16,482.  During 
the  remaining  five  mcnths,  27,828  tons  was  mined, 
and  also  51,761  tons  from  the  Jumpers,  and  the  share 
of  the  profits  due  to  the  Treasury  was  /9133.  On  the 
clean-up  of  the  Treasury  mill  gold  worth  /15,0S1  was 
recovered.  After  administration  expenses  and  taxes 
had  been  paid  the  balance  of  profit  for  the  year  was 
/36,181,  and  this  added  to  the  balance  brought  forward 
from  the  previous  year  made  a  total  credit  balance  of 
;^80,328,  which  is  being  kept  in  hand  for  the  purpose 
of  acquiring  other  interests  or  properties.  When  the 
Treasury  was  taken  over  on  November  last,  it  was 
estimated  that  the  available  ore  was  250,000  tons 
averaging  6  dwt. 

Otavi  Mines  &  Railway.  —  This  company  was 
formed  in  Berlin  in  1900  to  acquire  copper-lead  mines 
at  Otavi  and  Tsumeb,  in  German  South  West  Africa, 
and  to  build  a  railway  from  the  coast  at  Swakopmund. 
The  higher  grade  ore  is  shipped  to  Germany,  and  the 
remainder  smelted  on  the  spot,  yielding  metallic  lead 
and  copper  matte.  The  report  for  the  year  ended 
March  31  shows  that  in  spite  of  the  low  price  of  cop- 
per, and  of  shortage  of  labour,  the  production  and 
profit  have  been  fairly  well  maintained.  The  amount  of 
ore  mined  was  42,000  tons  as  compared  with  49,500 
tons  during  the  previous  year  ;  of  this  31,600  tons  was 
shipped,  averaging  16%  copper,  24%  lead,  and  9oz. 
silver,  and  the  remainder  was  smelted,  producing  2040 
tons  of  lead,  and  2220  tons  of  copper  matte  averaging 
47%  copper  and  26%  lead.  As  recorded  a  year  ago, 
the  cost  of  mining  went  up  from  lis.  to  25s.  per  ton 
when  underground  work  was  commenced  instead  of 
opencut.  During  the  past  year  modifications  have 
been  introduced  in  the  method  of  mining,  more  adapted 
to  the  brittle  and  fissured  nature  of  the  ore,  and  in 
consequence  the  cost  has  been  reduced  to  23s.  The 
business  of  the  company  also  includes  the  administra- 
tion of  the  railway.  The  total  profit  for  the  year  was 
;^224,500,  out  of  which  ;^85,000  has  been  paid  to  the 
ordinary  shareholders,  /65,000  to  the  deferred  share- 
holders, ^'10,000  to  the  directors,  and  /57,800  placed 
to  reserve. 

Mond  Nickel. — This  company  was  formed  in  1900  to 
acquire  the  process  of  extraction  of  nickel  from  nickel- 
copper  matte  invented  by  Ludwig  Mond,  whereby  the 


nickel  is  removed  as  a  volatile  carbonyl  compound ,  The 
Victoria  mines  in  the  Sudbury  district  of  Ontario  were 
bought  and  the  matte  there  produced  is  shipped  for 
treatment  at  Clydach  in  the  Swansea  valley.  The 
copper  is  recovered  in  the  form  of  sulphate.  The 
first  preference  dividend  was  earned  during  the  year 
ended  April  30,  1904,  and  next  year  6%  was  paid  on 
the  ordinary  shares  ;  the  year  after  the  deferred  shares 
received  18%.  The  ordinary  dividend  was  10%  in 
1905-6,  12i%  in  1906-7,  15%  in  1907-8  1908-9  and 
1909-10,  and  16j%  in  1910-11.  The  share  capital 
consists  of  ;^400,000  preference,  ;^300,000  ordinary 
and  /50, 000  deferred  shares.  The  report  for  the  year 
ended  April  30  last  shows  a  profit  of  ;/^161,544,  out  of 
which  /26,366  at  the  rate  of  7%  has  been  paid  on  the 
preference  shares,  ;^45,906  or  16|%  on  the  ordinary 
shares,  and  /26,131  on  the  deferred  shares.  The  pro- 
gress of  the  company  is  well  maintained.  In  order  to 
meet  the  increased  demand  for  the  products,  new 
smelting  works  are  to  be  erected  at  Coniston,  near 
Romford  Junction,  Ontario,  and  for  this  purpose  an 
issue  of  /250,000  debentures  has  been  made. 

TRADE    NOTES 

Most  of  the  trade  publications  mentioned  in  this 
column  are  available  for  distribution  and  the 
manager  of  ''The  Mining  Magazine''  will  be 
pleased  to. secure  copies  for  persons  interested. 

The  British  Humboldt  Engineering  Co.  have  con- 
tracted to  supply  two  of  their  mechanical  roasters  to 
the  Falmouth  Consolidated  Mines,  near  Truro,  Corn- 
wall. These  mines  yield  a  tin  ore  that  contains  much 
pyrite  and  arseno-pyrite,  and  the  roasting  without 
annoying  neighbouring  farmers  has  been  a  trouble- 
some business.  The  provision  of  this  new  plant  is 
part  of  the  scheme  for  obtaining  an  efficient  roast  and 
for  obviating  the  fume  and  dust  difficulty. 

The  Sullivan  Machinery  Co.'s  Bulletins  66B  and66C 
have  been  made  up  with  the  usual  care  taken  by  the 
publication  department  of  this  company  and  give 
many  interesting  details  about  hammer  drills  for  min- 
ing work  and  the  mountings  and  accessories  necessary 
for  the  larger  rock-drills.  The  company  also  inform 
us  that  Mr.  Hart  O.  Berg  has  been  appointed  their 
representative  in  France. 

The  Stephens-Adamson  Manufacturing  Co.  keep 
buyers  in  touch  with  improvements  and  new  installa- 
tions by  issuing  a  monthly  bulletin  entitled  '  The 
Labor  Saver.'  The  July  issue  is  just  to  hand  and  is 
full  of  interesting  matter  pertaining  to  transmission, 
conveying,  and  elevating  machinery. 

Werf  Conrad,  Ltd.  have  sent  out  additional  circulars 
under  date  of  July  1911  giving  the  latest  results  from 
their  dredges  working  on  the  Tongkah  Harbour  and 
the  Renong  river,  which  should  prove  very  satisfactory 
not  only  to  the  owners  of  the  property  but  to  the 
designers  and  builders  of  the  three  bucket  dredges. 

Fraser  &  Chalmers  are  agents  for  Amme,  Giesecke 
&  Konegen,  of  Brunswick,  and  were  responsible  for 
introducing  the  Giesecke  Mill  in  Johannesburg.  The 
recent  trials  of  this  mill  at  the  Geldenhuis  Instate  have 
created  a  great  deal  of  interest,  and  were  referred  to 
in  our  July  issue. 

Marcus  Ruthenburg  has  issued  a  neat  bulletin 
describing  the  merits  of  electric  furnaces  in  the  treat- 
ment of  refractory  ores.  Mr.  Ruthenburg  has  devot- 
ed his  entire  time  to  this  subject  for  many  years. 

The  Moore  Filter  Co.  announce  that  they  have 
closed  a  contract  to  equip  the  Hollinger  mill  at  Porcu- 
pine with  a  Type  A  Moore  Filter  designed  to  have  an 
ultimate  capacity  of  1000  tons  per  day. 


The  Mining  Magazine 


Vol.  V. 


LONDON.  SEPTEMBER   1911. 


No.  3 


Scientia   non   habet   inimicum   nisi   ignorantem. 


T.    A.    RICKARD,    Editor.  EDGAR    RICKARD,    Business  Manager. 

PUBLISHED  BY  THE  MINING  PUBLICATIONS  LTD.,  at  819  SALISBURY  HOUSE,  LONDON,  E.C 

Issued   on   the    15th   day   of   each   month. 

Telegraphic  Address  :    Oligoclase.     Codes;  MciVcz7/,  both  editions.     Telephone:    8938   London   Wall. 

Branch  Offices  : 
SAN  FRANCISCO:  420  MARKET  STREET.     CHICAGO:  934  MONADNOCK  BUILDING.      NEW  YORK:  29  BROADWAY 

Agents  for  the  Colonies  : 
GORDON    &    GOTCH,    LONDON,    MELBOURNE,    Etc.    (SOUTH    AFRICA:    CENTRAL    NEWS    AGENCY.    LTD.) 

Registered  with  the  G.P.O.  for  transmission  to  Canada  by  Canadian  Magazine  Post. 

SUBSCRIPTION    RATES. 

United  Kingdom  and  Canada,  12  Shillings  (Single  Copy,  Is.)    ...    Abroad,  16  Shillings  (Single  Copy,  Is.  4d.) 


CONTENTS. 


PAGE 

Review  of  Mining 162 

Statistics  of  Production 169 

Editorial 

Notes 170 

East  Rand  Proprietary  172 

Prestea 1 74 

Another  Cassandra 174 

The  Railway  Strike 175 

Official  Valuation  of  Shares 178 

Assays 179 

Indexes  of  Technology  1 80 

Buying  Prospects  182 

Special  Correspondence 

Cordova,  Alaska 183 

Toronto 186 

Johannesburg 189 

San  Francisco 191 

Mexico 193 

Camborne 194 

New  York 196 

Salt  Lake  City 198 

Melbourne 199 

Articles 

Deep  Mining  on  the  Rand 

Rowland  Gascoyne  202 

Cyanidation  of  Silver  Ore  at  Cobalt...  206 

The  Finance  of  a  Mine.   IV 

M.  H.  Burnham  209 

The  Chino  Copper  Mine 212 

Mineral  Resources  of  Central  Africa 

Owen  Letcher 213 


Metal  Markets 

Personal 

Discussion 

Percentage  of  Recovery... T.  /.  Hoover 

Values William  R.  Rumbold 

Official  Valuation  of  Shares  Speculator 

Prospecting  in  the  North../?.  \V.  Brock 

Critical  Moisture  in  Tube  -  Mill  Feed 
John  W.  Bell;  A.  Qnartano 

Mine  Salting U^.  N.  Cuniniiiigs 

Pebbles  for  Tube-Milling..A.  W.  Allen 
Precis  of  Technology 

Alloys  of  Refractory  Metals 

Concrete  Shafts  

Queensland  Miners'  Health   

Salt  from  Salt  Lake  

Concentration  at  Frontenac   

Concentrating  Silver  Ore  at  Cobalt  ... 

Ore  in  Clay  Selvages 

The  Aluminium  Industry  

Rhodesian  Tin  

Removing  Pyrite  from  Blende 

Hoisting  by  Compressed  Air 

Amalgamation  on  the  Rand 

Charcoal  in  Cyanide  Tailing 

Modified  Square-Set 

Sintering  Iron  Ores 

Chalcocite  as  a  Primary  INIineral 

Cyaniding  Ohinemuri  River  Sand 

Current  Literature 

Books  Reviewed 

Company  Reports 

Trade  Notes  


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REVIEW    OF    MINING 


Introductory. — The  mining  market  has 
passed  through  a  most  troublous  period  since 
our  last  issue  appeared,  every  department 
having  suffered  through  forced  liquidation. 
Intrinsic  values  were  disregarded  and  it  maybe 
said  safely  that  the  pendulum  of  speculation, 
which  in  good  times  goes  considerably  beyond 
the  limit  of  merit,  is  at  the  present  moment 
performing  a  reversed  swing.  This  state  of 
affairs  is  primarily  due  to  the  fact  that  local 
English  and  Continental  holders  of  mining 
shares  are  easily  alarmed  by  anything  unto- 
ward in  the  political  world,  whereas,  if  inves- 
tors were  logical,  mining  shares  would  be  the 
last  holdings  to  be  sold,  as  they  are  practically 
immune  from  the  direct  consequences  of  a 
European  conflagration.  The  technical  posi- 
tion of  the  market,  which  for  many  months 
was  unique  as  to  its  soundness,  has,  strange 
to  say,  become  worse  in  consequence  of  the 
continued  decline  in  prices,  because  commit- 
ments that  were  held  outside  the  market, 
against  loans,  with  ample  margin  with  the 
banks,  have  become  doubtful  and  have  re- 
quired adjustment  either  by  reducing  the  ob- 
ligation or  by  supplying  fresh  margin.  At  the 
same  time  there  is  no  doubt  that  the  bear  ele- 
ment in  mining  shares,  particularly  as  regards 
the  leading  securities,  has  considerably  in- 
creased. Provided  a  favourable  solution  of  the 
Moroccan  question  is  reached  soon,  a  scramble 
for  shares  will  be  witnessed.  It  is  doubtful, 
however,  if  the  improvement  could  be  main- 
tained, as  all  the  wreckage  that  has  now  been 
taken  over  from  weak  holders  will  have  to  be 
sold  first.  On  the  other  hand,  it  is  gratifying 
to  observe  that  bargain-hunters  are  already 
making  their  appearance,  with  good  reason. 

The  South  African  market  was  particularly 
upset  by  the  mysterious  fall  in  East  Rands, 
followed    by    a    nebulous    explanation   in  an 


official  circular.  Confidence  in  mining  ven- 
tures has  been  much  shaken  by  the  failure  of 
one  of  the  leading  concerns  to  maintain  the 
earnings  so  clearly  promised  by  its  chairman 
at  the  last  meeting.  It  is  regrettable  that 
shareholders  should  have  been  kept  in  the 
dark  as  to  a  serious  trouble,  after  it  had 
come  to  the  notice  of  the  Board  for  some  time 
past.  There  is  no  excuse  whatever  for  the 
delay  in  acquainting  the  shareholders  with  the 
facts.  It  is  evident  from  the  circular  that  the 
actual  millmg  and  cyanide  results  have  shown 
a  discrepancy  as  compared  with  the  assay- 
value  of  the  ore  sent  to  the  mill.  Being 
puzzled  at  this  occurrence,  the  Board  ordered 
a  careful  investigation  to  ascertain  whether 
the  assay-plan  was  faulty  or  the  cyanide  plant 
ineffioient,  or,  as  a  last  alternative,  whether 
dishonesty  was  rampant.  They  were  aware 
all  the  time  that  something  was  wrong,  but 
they  did  not  think  it  necessary  to  inform  the 
shareholders.  On  the  other  hand,  the  Euro- 
pean Committee  recently  found  it  necessary 
to  add,  to  a  formal  notice  by  the  Johannesburg 
Board,  that  they  considered  the  information 
concerning  the  Cason  was  most  favourable  and 
highly  important  to  the  future  development  of 
this  particular  section.  It  is  clear  therefore 
that  while  unfavourable  and  alarming  news, 
which  resulted  in  the  declaration  that  a  reduc- 
tion of  the  dividend  would  ensue,  was  with- 
held, favourable  news  was  amplified  by  special 
observations.  Thus  the  directors  have  left 
themselves  open  to  the  suspicion  that  they 
have  used  privileged  information  to  their  own 
advantage.  No  wonder  that  under  such  cir- 
cumstances the  public  is  losing  confidence  in 
group  control.  We  refer  to  the  matter  else- 
where, and  we  desire  to  repeat  a  warning  to 
shareholders,  in  East  Rand,  Prestea,  and  other 
mines  under  a  cloud,  not  to  be  scared  into  a 


162 


SEPTEMBER,    1911 


163 


sale  of  their  holdings  by  a  depreciation  fully 
as  foolish  as  the  reckless  optimism  of  an  earlier 
period.  They  may  take  it  from  us  that  by 
the  time  bad  news  is  officially  given  it  is  too 
late  to  sell,  since  by  that  time  the  leakage  of 
unfavourable  items  has  been  fully  used  by 
well  informed  operators,  who  will  then  be  on 
the  bear  side  and  only  too  glad  to  see  the 
public  further  frightened. 

The  West  African  market  has  had  troubles 
of  its  own,  the  Prestea  coming  under  a  cloud. 
We  refer  to  the  episode  on  another  page. 
The  delay  in  full  production  owing  to  the  in- 
ability of  the  management  to  extract  ore 
sufficient  for  110  stamps  has  depressed  the 
shares  more  than  the  single  unpleasant  fact 
might  warrant,  but  it  serves  to  emphasize  the 
loss  of  confidence  due  to  the  manner  in  which 
the  small  shareholders  are  treated. 

In  the  West  Australian  market  the  fall  in 
Kalgurli  has  been  pronounced.  This  is  due 
to  unfavourable  developments  on  the  two 
levels  below  1650  feet  and  the  consequent 
fear  that  the  mine  is  bottomed ;  but  the  scare 
seems  overdone.  Likewise  the  Associated, 
with  another  decline,  illustrates  the  tendency 
of  the  public  to  sell  on  a  falling  market  and 
to  buy  at  the  top  of  a  boom.  This  company 
has  gilt-edged  securities  and  a  remnant  of 
ore  that  together  represent  a  sum  of  money 
in  excess  of  the  valuation  given  to  the  pro- 
perty, which  still  has  some  good  ground  worth 
prospecting. 

Among  Russian  securities,  Lena  Goldfields 
were  prominent  by  their  firmness,  which  is 
partly  explained  by  a  bear  account  and  partly 
by  enlarged  production.  Now  that  Russian 
speculators  have  bought  large  blocks  of  these 
shares  at  boom  prices  they  are  beginning  to 
kick  because  they  have  so  little  to  say  in  the 
management  of  the  mines  and  suggest  that 
the  head  office  should  be  nearer  home,  for  ex- 
ample, at  Paris,  The  incident  bears  a  re- 
semblance to  the  Mexico  of  El  Oro  affair. 
Spassky  and  Atbasar  shares  have  been  sub- 


jected to  heavy  liquidation  for  Paris  account, 
but  news  from  both  properties  is  excellent. 

Porcupine  shares  have  been  dull  and  lifeless. 

Copper  shares  were  weak,  particularly  Rio 
Tinto,  on  French  liquidation,  the  stock  being 
mostly  held  on  the  other  side  of  the  Channel. 
The  decline,  however,  is  reasonable  seeing 
that  the  announced  restriction  of  output  would 
necessitate  a  reduction  in  the  dividend  ;  for  a 
smaller  output  will  not  be  compensated  by  a 
higher  price  for  the  metal. 

Transvaal. — In  July  the  output  of  gold 
reached  a  new  record  and  for  the  first  time 
attained  a  value  of  over  ^3,000,000.  This 
fact  would  have  cheered  the  market  if  it  had 
not  been  accompanied  by  discouraging  labour 
statistics.  The  decrease  of  5358  natives  em- 
ployed on  the  gold  mines  brought  the  total 
down  to  181,582,  as  against  181,514  in  July  of 
last  year.  At  this  season  the  Kaffirs  migrate 
to  their  kraals  to  do  their  farming  and  there- 
fore a  diminution  of  mine-workers  is  expected, 
but  it  was  hoped  that  it  would  not  prove  so 
excessive  as  to  Vv'ipe  out  the  gain  due  to 
vigorous  recruiting  for  months  back.  The 
record  gold  output  suffered  further  detraction 
by  reason  of  disappointing  individual  returns. 
While  the  total  working  profit  on  the  Rand 
amounted  to  ;^969,687  as  against  i;960,381  in 
June  and  ir937,456  in  July  1910,  this  small  in- 
crease is  not  proportioned  to  the  gross  output* 
for  a  new  producer,  the  Brakpan,  is  to  be 
credited  with  a  contribution  of  ;^  13,000  in  pro- 
fit. A  comparison  with  the  corresponding 
month  of  last  year  shows  an  increased  ton- 
nage of  ore,  from  1,814,686  to  2,095,220,  but 
the  yield  per  ton  has  declined  from  28s.  Id. 
to  27&.  2d.  and  the  average  cost  has  risen 
slightly,  from  17s.  8d.  to  17s.  lOd.  per  ton,  the 
profit  averaging  therefore  10s.  4d.  in  July  1910 
and  9s.  4d.  in  July  1911.  On  tlie  whole,  it 
is  evident  that  the  increased  tonnage  of  ore  and 
greater  output  of  gold  were  not  accompanied 
by  a  corresponding  lowering  of  cost ;  hence  the 
final  result  is  scarcely  satisfactory. 


164 


THE    MINING    MAGAZINE 


The  decrease  in  the  number  of  natives 
employed  in  the  Transvaal  gold  mines  during 
August  was  1772.  This  loss  is  less  than 
during  the  previous  three  months,  when  alto- 
gether the  decrease  was  12,746,  but  it  is 
greater  than  in  August  last  year  when  the 
figure  was  683.  The  number  employed  on 
the  gold  mines  on  August  31  was  179,810  as 
compared  with  180,831  a  year  ago. 

The  Brakpan  is  a  cheerful  spot  in  Rand 
mining.     For  August  the  profit  was  ;^20,575, 
as  compared  with  ^12,600  in  July.     At  pre- 
sent 100  stamps  are  at  work,  crushing  35,000 
tons  monthly  at  a  profit  of   lis.  9d.  per  ton. 
When  the  entire  mill  of   160  stamps  is  oper- 
ating, the  returns  will  justify  expectations  of 
dividends  at  the  rate  of  50%  on  the  capital. 
This  will  enrich  the  Transvaal  Coal  Trust 
and  Consolidated  Mines  Selection  companies, 
both  owning  large  blocks  of  Brakpan  shares. 
Rhodesia, — The   July  statistics   are    ex- 
cellent, showing  an  output  of  56,407  ounces, 
valued  at  ^237,517.     This  is  an  increase  of 
^"22,170  as  against  June  of  last  year.     Seven 
more  producers  appear  on  the  list.    The  most 
notable  gain  is  that  of  the  Lonely  Reef,  where 
the  new  mill  has  been  started,  treating  2940 
tons  for  an  output  oi  £l  1,673  during  the  month 
under  review.    Slight  increases  are  also  shown 
by  the  Wanderer,    Globe    &    Phoenix,   East 
Gwanda,  and  Thistle-Etna.     By  reason  of  the 
July  increase  the   total   for    the    first    seven 
months  is  better  than  that  for  the  correspond- 
ing period  of  any  preceding  year. 

The  Shamva  quarterly  report  suffered  from 
an  error  that  spoiled  the  authenticity  of  the 
information,  but  we  note  that  in  the  three 
months  ending  with  June  no  less  than  226,819 
tons  was  added  to  the  reserve,  making  it 
1,245,932  tons.  Mill-tests  continue  satisfac- 
tory. Later  news  concerning  the  cross-cut- 
ting on  the  No.  4  adit  shows  110  feet  of  ore 
containing  over  8  dwt.  per  ton,  indicating  a 
grade  above  the  average  of  that  remarkable 
orebody.      It   is  also   reported   that  the  two 


lowest  levels  at  the  Lonely  Reef  mine  are 
making  an  excellent  showing,  the  lode  at  the 
7th  level  averaging  so  far  3i  oz.  for  4i  feet. 
Water  has  hindered  sinking.  The  mill  has 
been  working  at  full  capacity  since  August  27. 
Interest  in  tin  prospects  is  lively  in  the 
Enterprise  district  and  promising  finds  have 
been  made  at  Abercorn  and  Victoria.  In  this 
case  no  ancient  workings  exist,  so  that  the 
modern  prospector  has  to  dig  his  own  holes  to 
test  the  tin  lodes.  So  far  he  has  indulged  in 
exuberant  pegging  of  claims,  some  of  which 
are  now  under  option  to  companies  likely  to 
undertake  serious  work. 

West  Africa. — The  output  of  gold  for 
July  is  officially  stated  to  have  been  22,510 
ounces,  worth  ^'91,555.  This  is  practically 
the  same  as  in  June.  The  first  seven  months 
show  a  total  of  134,198  oz.,  or  16,527  oz.  more 
than  was  produced  in  the  corresponding  period 
last  year.  The  Prestea  did  no  better  and  no 
worse  than  in  June;  the  same  is  true  of  the 
Ashanti  Goldfields,  which  continues  to  be  the 
most  productive  property  on  the  Gold  Coast. 
The  Bibiani  exhibits  steady  improvement. 

We  refer  elsewhere  to  the  Prestea  affair, 
which  has  had  a  bad  effect  on  the  West 
African  market.  During  the  quarter  ending 
June  30  the  reserve  at  Abbontiakoon  was  in- 
creased by  133,609  tons  of  ore  averaging  7 
dwt.  per  ton.  This  is  a  lower  content  than 
that  of  the  ore  previously  developed,  as  may 
be  seen  from  the  fact  that  the  total  reserve 
on  June  30  was  592,191  tons  averaging  10"22 
dwt.,  but  the  difference  is  explained  by  the 
inclusion  of  blocks  of  ore  previously  deemed 
unprofitable.  The  Taquah  mine  has  resumed 
crushing  with  20  of  the  50  stamps.  Since 
July  of  last  year  when  milling  was  suspended, 
the  work  has  been  centred  on  development 
underground. 

Australasia. — That  there  is  a  general 
belief  in  a  period  of  high  prices  of  lead  and 
zinc  in  the  near  future  is  indicated  by  the  re- 
opening of  the  Broken  Hill  Proprietary  mine. 


SEPTEMBER,    1911 


165 


At  present  the  output  is  restricted  to  4500 
tons  per  month,  only  one  third  of  that  in 
earlier  days.  Important  economies  have  been 
introduced  at  the  smelter,  especially  in  connec- 
tion with  the  method  of  charging  the  furnaces, 
in  order  to  counterbalance  the  recent  advance 
in  wages.  The  zinc-distilling  plant  is  to  be  in 
full  operation  by  November,  the  difficulties  in 
connection  with  retort-manufacture  having 
been  overcome.  Another  interesting  item  of 
news  is  that  by  means  of  a  modification  of  the 
Potter  process  it  is  now  possible  to  utilize  the 
accumulated  slime.  The  manager,  Mr.  G.  D. 
Delprat,  has  started  for  a  journey  of  observa- 
tion round  the  world.  An  intelligent  guess 
may  connect  his  tour  with  a  preparatory  study 
of  the  best  methods  of  developing  the  iron 
ore  at  Iron  Knob  that  has  hitherto  been  used 
solely  as  a  flux  in  lead-smelting. 

The  development  of  wolfram  deposits  pro- 
mises to  add  an  important  industry  to  Austra- 
lian mining.  The  deposits  at  Mount  Carbine 
in  North  Queensland,  not  far  from  the  port  of 
Cairns,  and  in  the  district  usually  associated 
with  tin,  are  now  being  regularly  worked  and 
the  ore  dressed  in  a  modern  concentration 
plant.  Block  14  company  of  Broken  Hill  has 
taken  up  wolfram  mining  by  acquiring  the 
property  of  the  Torrington  Ore  Co.,  at  Deep- 
water,  situated  in  the  New  England  range  in 
the  northeast  corner  of  New  South  Wales. 
This  mine  also  yields  bismuth.  It  has  been 
worked  on  a  small  scale  for  a  few  years,  but 
its  ore  reserve  is  sufficiently  large  to  warrant 
operations  on  a  greatly  extended  scale. 

Developments  at  the  bottom  of  the  Great 
Fingall,  on  the  new  orebody,  are  still  en- 
couraging ;  the  north  drift  on  the  18th  level 
shows  better  ore  than  the  corresponding  por- 
tion of  the  16th  ;  but  nothing  like  the  bonanza 
that  made  the  mine  famous  has  yet  been  found 
in  depth.  At  the  Lancefield  an  improvement 
in  the  milling  is  recorded,  the  extraction  being 
85%.  This  has  hitherto  been  the  chief  diffi- 
culty. 


On  August  28  a  gleam  of  sunshine  fell  on 
the  Waihi,  the  Empire  lode  having  been  cut 
on  the  10th  level,  and  the  first  three  feet  of  it 
showing  ore  assaying  £3%  per  ton.  Of  course, 
it  is  nice  to  hear  of  good  ore  being  found  on 
the  bottom  level,  but  it  is  obvious  that  the 
recent  slump  has  not  chastened  the  spirit  of 
speculators  in  Waihi,  for  a  couple  of  assays 
induced  buying  that  had  the  effect  of  increas- 
ing the  market  price  of  the  mine  by  nearlj 
;^500,000.  Later  news  shows  that  the  entire 
30  feet  of  the  Empire  lode  on  the  bottom 
level  averages  54s.  per  ton,  as  against  a  work- 
ing cost  of  about  20s.  per  ton  ;  but  even  these 
promising  figures  are  of  no  special  significance 
until  the  length  of  the  orebody  has  been  as- 
certained by  further  development. 

Canada. — The  new  company  to  operate  in 
the  Yukon  is  called  the  Granville  Mining  Co. 
We  are  informed  that  there  was  no  public  is- 
sue, the  necessary  capital  being  subscribed 
privately.  The  directors  are  Mr.  F.  A.  Govett 
of  the  Ivanhoe  Gold  Corporation,  Major  H, 
L.  Sapte  of  the  Consolidated  Gold  Fields  of 
South  Africa,  Mr.  J.  S.  Wetzlar  of  the  Con- 
solidated Mines  Selection  Co.,  Messrs.  Wil- 
liam Trask,  A.  N.  C.  Treadgold,  A.  Chester 
Beatty,  and  H.  C.  Hoover.  Obviously 
enough  capital  and  talent  is  represented  on 
the  board  to  ensure  the  application  of  the  ut- 
most skill  and  experience  in  dredging  and 
hydraulic  mining.  The  capital  of  the  com- 
pany is  /"l, 200,000.  A  power-plant  with  a 
capacity  of  10,000  hp.,  with  provision  for  a 
further  5000  hp.,  if  required,  has  already 
been  constructed  in  the  Klondike  valley.  Mr. 
A.  H.  Rogers,  of  New  York,  is  the  consult- 
ing engineer  and  is  now  on  the  ground  design- 
ing the  further  equipment  necessary  for  en- 
larged operations. 

The  most  interesting  news  from  Porcupine 
is  that  relating  to  a  discovery  at  the  North 
Dome.  The  manager  is  Mr.  P.  Kirkegaard, 
a  responsible  engineer.  The  galaxy  of  talent 
that  left  London  recently  to  inspect  Porcupine 


166 


THE    MINING    MAGAZINE 


did  not  spend  much  time  at  the  mines.  Mr. 
E.  T.  McCarthy,  however,  made  a  recon- 
naissance sufficient  to  warrant  an  impression 
that  several  promising  mines  have  been  opened 
up.  The  maximum  depth,  not  counting  bore- 
holes, is  only  200  feet  in  the  four  principal  pro- 
perties and  the  showing  of  free  gold  seems  to 
be  over-worked  for  the  purpose  of  booming 
the  district.  Publication  of  results  from  actual 
sampling  of  the  principal  workings  by  engi- 
neers of  reputation  would  do  much  to  increase 
public  confidence.  Meanwhile  we  hear  that 
the  Swastika  district,  about  50  miles  from 
Porcupine,  is  coming  to  the  front.  The  original 
discovery,  now  called  the  Swastika  mine,  has 
been  worked  for  two  years  and  is  200  feet 
deep.  A  small  mill  and  compressor  plant  has 
been  erected.  The  more  recent  discoveries 
are  on  the  Lucky  Cross,  Reeves  (of  the  Pike 
Lake  company),  and  Swastika  Consolidated. 
As  is  the  case  at  Porcupine  the  good  ore  shows 
free  gold,  and  if  no  gold  is  visible  the  quartz 
is  usually  poor. 

United  States. — Our  New  York  and 
San  Francisco  correspondents  send  an  inter- 
esting budget  of  news.  The  former  makes 
some  interesting  comment  on  the  copper  mar- 
ket and  refers  to  a  report  on  the  Lake  Superior 
mines  made  by  Mr.  J.  R.  Finlay  as  a  basis  for 
taxation  by  the  State  of  Michigan.  Knowing 
Mr.  Finlay,  we  consider  his  appraisal  trust- 
worthy and  of  great  importance  to  those  inter- 
ested in  the  price  of  copper.  We  also  publish 
another  article  from  Alaska,  written  by  a  min- 
ing engineer  in  whom  we  place  complete  con- 
fidence. These  letters  relating  to  mining  in 
the  northern  Territory  are  worthy  of  careful 
reading,  as  we  have  reason  to  believe  that  the 
Alaska  mining  region,  with  the  adjoining  Cana- 
dian territory,  will  attract  increased  attention 
in  the  near  future.  It  is  a  country  particularly 
rich  in  gold  and  copper.  Lack  of  transport 
facilities  and  severe  climatic  conditions  have 
hindered  rapid  development,  but  both  are  being 
overcome.     The  climate  is  wonderfully  stimu- 


lating and  promotes  energetic  labour  to  a  de- 
gree strongly  in  contrast  with  the  malarial 
tracts  of  the  tropics. 

Among  dredging  enterprises  the  first  place 
is  held  by  the  Yuba  Consolidated  Gold  Fields, 
a  company  controlled  by  Boston  people. 
Among  the  large  shareholders,  however,  is 
the  American  representative  of  the  Consoli- 
dated Gold  Fields  of  South  Africa.  In  the 
year  ending  February  28,  1911,  the  dredges  of 
this  company  in  California  handled  13,970,728 
cubic  yards  of  gravel,  yielding  $2,927,246. 
The  profit  was  $2,181,336,  all  of  which,  with 
the  exception  of  $200,000,  was  distributed  in 
dividends.  The  cost  of  dredging  was  5'67 
cents  per  yard,  on  gravel  yielding  21  cents  per 
cubic  yard.  We  note  also  that  the  dredges  of 
the  Natomas  Consolidated  extracted  .$167,125 
during  July,  as  against  $105,597  in  the  cor- 
responding month  last  year.  The  profit  has 
increased  proportionately  from  $46,963  to 
$92,984  for  the  month.  The  yardage  is  not 
given.  Last  year  the  average  yield  was  9'64 
cents  and  the  cost  4'52  c.  per  cubic  yard. 

Mexico.  —  Affairs  have  become  more 
settled,  but  the  labour  troubles  stimulated  by 
the  revolutionary  outbreak  are  still  a  source 
of  anxiety  to  mine  managers.  For  instance, 
at  the  El  Mayo  general  meeting  it  was  stated 
that  since  the  revolution  it  has  proved  difficult 
to  get  men  to  work  in  the  mine,  so  that  de- 
velopment has  been  checked.  As  the  election 
for  President  comes  in  October  and  General 
Madero  has  been  nominated,  it  may  be  ex- 
pected that  the  new  Government  will  be  more 
firmly  established  before  the  end  of  the  year, 
and  therefore  better  able  to  cope  with  the 
situation.  If  Madero  is  not  elected  by  a  large 
majority,  it  is  possible  that  his  competitor  may 
foment  further  discontent. 

The  El  Oro  Mining  &  Railway  Co.  sets  a 
good  example  in  issuing  the  resident  manager's 
report  as  soon  as  it  is  received,  although  the 
document  is  prepared  for  the  annual  meeting 
at  least  a  month  later.     Mr.  A.  F.  Main  pre- 


SEPTEMBER,    1911 


167 


sents  a  fine  record,  the  working  cost  having 
been  reduced  to  $3*90,  which  is  an  improve- 
ment of  more  than  $  1  per  ton.  Thus,  although 
the  assay-value  of  the  ore  was  only  $7'63, 
as  against  $8'86  last  year,  the  profit  was 
$984,333,  or  only  slightly  less  than  in  the  pre- 
ceding period.  The  reserve  of  ore  has  been 
increased  by  42,500  tons,  to  484,139  tons. 
Lower  cost  of  operation  has  enabled  the  man- 
ager to  utilize  the  low-grade  ore  left  in  the 
upper  workings  in  the  days  when  less  economi- 
cal methods  were  in  vogue. 

The  Torres  Mines,  a  company  registered  in 
1906  to  acquire  the  assets  of  the  Cherokee 
Goldfields,  in  Chihuahua,  has  been  re-organized 
andre-christened  under  the  name  of  the  Ceniza 
Gold  Mines.  Funds  have  been  provided  for 
a  resumption  of  work,  which,  the  manager  re- 
ports, is  now  practicable,  owing  to  an  improve- 
ment in  the  political  situation. 

Siberia. — The  stacker-scow  of  the  Orsk 
Goldfields  is  doing  good  work  on  the  Pok- 
rovsky  ground,  renewing  the  hope  that  the 
big  dredge  when  completed  will  retrieve  the 
fortunes  of  this  unlucky  enterprise.  In  July 
the  Pokrovsky  plant  washed  24,400  cubic 
yards  of  gravel  for  a  yield  of  ^6000  in  gold, 
at  an  operating  cost  of  only  ;^700.  The  yield 
therefore  is  again  4s.  lid.  or  over  1  dwt.  per 
yard,  while  the  cost,  exclusive  of  administra- 
tion (which  is  high),  is  only  7d.  per  cubic 
yard. 

We  mentioned  recently  that  the  Russian 
Mining  Corporation  had  an  option  on  the 
Syssert  estate,  near  Ekaterinburg,  in  the  Ural 
region,  and  near  Kyshtim.  After  Mr.  C.  M. 
Rolker's  inspection  was  finished,  he  asked  for 
an  extension  of  time,  in  order  to  do  some 
further  drilling,  to  test  the  lenticular  ore- 
bodies.  This  request  being  declined,  the  op- 
tion expired ;  whereupon  an  offer  was  made 
by  Mr.  L.  Urquhart  for  the  Perm  Corpora- 
tion, the  parent  of  the  Kyshtim  enterprise. 
This,    however,    was    also    declined    by    Mr. 

Dimitri  P.  Solomirsky,  the  controlling  owner 
3—2 


of  the  Syssert  property.  This  gentleman 
thereupon  gave  the  option  to  Mr.  V.  C.  Pav- 
lovsky,  a  solicitor  at  Ekaterinburg,  represent- 
ing a  Russian  group,  the  members  of  which 
are  now  settling  the  details  of  the  business. 

India. — The  development  in  depth  from 
Garland's  shaft  at  the  Champion  Reef  con- 
tinues to  give  good  results.  On  the  34th  level 
the  ore  is  decidedly  richer  than  on  the  33rd, 
At  several  points  the  assays  are  excellent ; 
for  instance,  at  the  end  of  the  south  drift  the 
lode  is  2  ft.  wide  and  averages  2  oz.  gold  per 
ton.  In  Carmichael's  section  of  the  same  mine 
some  good  finds  have  been  made  on  the  38th 
level.  From  the  Ooregum,  where  the  results 
of  development  have  been  disappointing  of 
late,  there  is  some  rather  more  hopeful  news. 
Between  the  4010  ft.  and  4100  ft.  levels  in 
Bullen's  section,  a  body  of  ore  has  been 
found  from  4  to  6  ft.  wide  and  assaying  from 
14  to  27  dwt. 

Chile, — The  Braden  Copper  Co.  is  an  en- 
terprise in  which  some  British  capital  has 
participated.  The  mines  are  situated  40  miles 
northeast  from  Rancagua,  which  is  60  miles 
southeast  of  Santiago.  We  are  informed  that 
the  new  concentrating  mill  is  finished,  giving 
a  capacity  of  1600  tons  daily.  The  old  mill 
has  been  re-built  so  as  to  be  capable  of  treat- 
ing 300  tons.  The  smelter  is  designed  to  treat 
200  tons  of  concentrate  daily,  it  being  expected 
that  2000  tons  of  ore  will  yield  200  tons  of  con- 
centrate. The  foundations  and  steel  building 
of  the  smelter  are  constructed  and  it  should 
be  ready  in  October.  The  converter  plant  will 
not  be  ready  until  spring.  As  an  alternative 
to  the  smelter,  the  erection  of  a  leaching  plant, 
with  electrolytic  precipitation,  has  been  begun, 
but  preference  is  being  given  to  hastening  the 
completion  of  the  smelter.  The  reserve  of  ore 
in  the  mine  is  estimated  at  10,000,000  tons, 
averaging  2"9%  copper,  and  it  is  anticipated  by 
Mr.  Pope  Yeatman  that  when  in  full  running 
order  the  cost  of  producing  copper  will  be  7 
cents  per  pound. 


168 


THE    MINING    MAGAZINE 


Oil. — At  the  end  of  August  a  number  of 
English  companies  organized  two  years  ago  to 
operate  in  the  Maikop  oilfield  received  official 
'  recognition  '  from  the  Russian  Government 
and  thereby  became  entitled  to  civil  and  other 
rights.  This  comes  at  an  opportune  time,  for 
after  a  tedious  period  of  prospecting  and  equip- 
ment some  actual  results  are  now  being  ob- 
tained. Pipe-lines  have  been  laid  down  and 
pumping  of  oil  has  begun.  A  low  price  for 
the  product  and  the  presence  of  impurities  in 
the  oil  have  delayed  the  realization  of  expec- 
tations formed  during  the  boom,  but  a  good 
deal  of  honest  work  has  been  accomplished 
and  better  days  should  be  in  store  for  those 
who  contributed  the  capital. 

Antimony. — Our  readers  will  have  noticed 
that  during  the  last  few  months  the  price  of 
antimony  rose  suddenly.  This  metal  is  not 
one  of  wide  application  but  it  is  of  importance 
to  the  typefounders  and  to  the  makers  of  anti- 
friction metals.  For  many  years  the  price 
has  been  low  owing  to  the  comparatively 
plentiful  supply  of  antimonial  ores.  German 
metal  people  in  February  formed  one  of  their 
favourite  controlling  syndicates,  and  put  the 
price  up  from  £2^  to  £2>'\.  The  weak  posi- 
tion of  the  syndicate  was  soon  shown  by  an 
appearance  on  the  market  of  supplies  from 
England,  France,  and  other  parts  of  Europe. 
What  broke  the  syndicate  eventually  was  the 
attitude  of  the  Chinese  mine-owners.  The 
syndicate  was  soon  dissolved  and  the  price 
has  relapsed  to  its  former  level  ^28  per  ton. 
Cornwall. — At  the  meeting  of  the  share- 
holders of  the  Dolcoath  mine  held  on  August 
26,  Mr.  R.  Arthur  Thomas  made  an  important 
statement  relating  to  new  discoveries  of  ore  be- 
tween the  490  and  510  fathom  levels.  Previous 
exploration  at  this  horizon  had  not  been  par- 
ticularly encouraging, but  winzesrecently  sunk 
from  the  eastern  ends  of  these  levels  have  dis- 
closed some  excellent  ore  averaging  at  least 
70  lb.  black  tin  per  ton.  The  new  shaft,  on 
which  ;^  120,000  has  been  spent,  is  expected 


to  be  in  operation  this  autumn,  and  will  ap- 
preciably reduce  the  cost  of  operation. 

An  even  more  interesting  meeting  of  share- 
holders was  that  of  the  Carn  Brea  &  Tincrof  t. 
On  thisoccasionthenew manager,  Mr.  Edward 
S.  King,  made  a  remarkable  impression  by 
delivering  a  speech  that  was  brimful  of  energy 
and  resourcefulness.  His  remarks  were  really 
an  indictment  of  the  inertness  that  has  for  too 
long  been  the  incubus  of  Cornish  mining,  but 
he  said  it  all  in  such  a  charming  way  that 
those   who    might   otherwise    have    resented 
criticism  of  past  methods  cheered  him  to  the 
echo.     We  wish  we  had  had  the  opportunity 
of  publishing  his  remarks  in  full,  for  though 
he  apologized    for   a    want  of  fluency   as  a 
speaker,  he  succeeded  in  putting  his  finger  in 
unmistakable  manner  on  the  defects  of  the  old 
methods   and    ideas.     For    instance,  he   had 
found  that  the  Cornish  stamps  had  no  bot- 
toms ;  on  putting  in  granite  blocks  to  serve 
as  foundations  for  iron  bottoms  he  raised  the 
daily  duty  per  stamp  from  13  cwt.  to  1  ton. 
He  is  going  to  revise  the  system  of  contract 
work,  and  wipe  out  of  existence  the  old  prac- 
tice of  cutting  the  rate  paid  to  the  competent 
miner  and  increasing  that  of  the  poor  hand. 
He  pointed  to   the    heavy   cost   involved  in 
pumping  in  five  shafts  and  hoisting  in  eight, 
an    absurd    plan    for  a  comparatively   small 
property    raising   less  than  80,000   tons  per 
annum.      He  also  demanded  that   the   van- 
ning shovel  analysis  should  be  superseded  by 
modern    scientific    methods,   and    that    these 
should    be    applied    throughout    the    various 
operations  at  every  point.     His  expressed  de- 
termination to  buy  his  supplies  in  the  cheapest 
market  will  act  as  a  healthy  tonic  throughout 
Cornwall  generally.     As  regards  the  future, 
he  stated  that  he  intended  to  put  his  house  in 
order  and  make  profits  with  the  small  means 
at  his  command,  and  not  until  he  has  proved 
both    the   mine  and  his  own   ability   will  he 
come  forward  with  a  request  for  new  capital 
to  provide  modern  machinery  and  plant. 


SEPTEMBER,    1911 


169 


STATISTICS 

Stocks  of  Copper  in  England  and  the  Continent. 
Reported  by  Henry  R.  Merton  &  Co. 


June  30 
Tons 

July  31 
Tons 

Aug.  31. 
Tons 

In  England 

55,579              53,807       '       52,661 
5,843                5,893        '         5,728 
1,500                2,075                1,975 
7,250               6.250               6,550 

In  France 

Afloat  from  Chile 

Afloat  from  Australia 

Total 

In  Rotterdam 

In  Hamburg  (estimated)... 

70,172       ;       68,025              66,914 

7,200       1         7,550                7.650 

10,100              10,400       ,       10,800 

American  Copper  Producers'  Association. 
In  Tons  of  2,240  lb. 


Produc- 
tion. 


Deliveries 


Domes- 
tic 


January  1911 '  51,650  i  18,785 

February    !  49,030  i  22,553 

March I  58,273  i  29,500 

April 52,716  <  23,396 

May '  56,679  '  28,814 

June I  55,605  :  27,525 

July  !  50,075  '  25,438 

August '  56,024  26,757 


Foreign  j   Total 


Stocks  at 
end  of 
month 


23,753 
20,139 
26,375 
27,736 
27,669 
31,902 
33,429 
31,185 


42,538 
42.692 
55,875 
51,132 
56,483 
59,427 
58,867 
57.942 


63.591 
69.929 
72,325 
73,909 
74,105 
70,283 
61,491 
59,573 


Production  of  Gold  in  the  Transvaal. 


Rand 


Else- 
where 


Total 


Totals.  1910 

January  1911 

February  

March 

April  

May    

June    

July 

August  


Oz. 

7,228,588 

625,862 
585,683 
649,247 
638,421 
658,196 
657,025 
679,881 
682,405 


Oz. 

305,532 

25,201 
24,965 
26,818 
29,293 
27,755 
27,544 
29,377 
31.002 


Oz. 

7,534,120 

651,027 
610,828 
676,065 
667,714 
685,951 
684,567 
709,258 
713,407 


Value 


Cost  and  Profit  on  the  Rand. 


Month. 


January  1911.. 

February 

March  

April 

May 

June  

July   

Total  sand  aver- 
ages for  1909.. 
Ditto  1910 


Tons 


Yield 
per  ton 


1.865,232 
1,712,198 
1,960.678 
1,926,583 
2,002,926 
1,986,559 


s. 
26 
28 
28 
27 
27 
27 
27 


20.543.759 
21.432,541 


28  11 
28    6 


Costs  I   Profit        Total 
per  ton  '  per  ton       profit 


s.  d. 

17  11 

18  3 
17  11 
17  6 
17  10 
17  11 
17  10 


s.  d. 


10 
10 
9 
10 
9 
9 
9 


930.059 
874.612 
949,415 
971,858 
956,823 
960,381 
969,687 


17 
17 


11 
10 


11,794,376 
11,216,105 


Natives  Employed  in  the  Transvaal  Mines. 


Gold 
mines 


January  31 183.268 

February  28 '    189.434 


March  31 
April  30... 
May  31  ... 
June  30  •■• 

July  31 

August  31 


193.457 
194,328 
190,392 
186,940 
181,582 
179,810 


Coal 
mines 


8,357 
8,513 
8,493 
8,511 
8,379 
8,212 
8,122 
8,182 


Diamond 
mines 


9,991 
9,814 
10,061 
10,272 
10,425 
10,597 
11,054 
11,292 


Total 


201.616 
207,761 
212.011 
213,111 
209,196 
205,749 
200,758 
199.284 


Gold  Output  of  India. 


Year  1909 


£2,083,901 


Year  1910 


£2,104,858 


Aug.  1911 
£181,124 


1911  to  date 


£1,231,880 


£ 

32,002,912 

2,765,386 
2,594,634 
2,871,740 
2.836,267 
2.913,734 
2,913,734 
3,012,738 
3,030,360 


Production  of  Gold  in  Rhodesia. 


Month. 


January 

February  ... 

March  

April 

May 

June  

July 

August 

September  ...I 

October 

November.. 
December-- 


1908 


Totals 


£ 

199.388 
191,635 
200,615 
212,935 
223,867 
224,920 
228,151 
230,792 
204,262 
205,466 
196,668 
217,316 


1909 


1910 


2,526,007 


£ 
204,666 
192,497 
202,157 
222,700 
225,032 
217,600 
225.234 
228.296 
213,249 
222,653 
236,307 
233,397 


£ 
227,511 
203,888 
228,385 
228,213 
224,888 
214,709 
195,233 
191,423 
178.950 
234,928 
240,573 
199,500 


1911 


£ 

207,903 
203,055 
231,947 
221,296 
211,413 
215.347 
237,517 


2,623,788  i  2,568,201 


Production  of  Gold  in  West  Africa. 


Month. 

1909 

1910 

1911 

Oz. 

Value 

Oz. 

Value 

Oz. 

Value 

' 

£ 

£ 

£ 

January  .... 

-    22.817 

91,112 

17,357 

70.699 

15.903 

66,107 

February    . 

21,403 

86,210 

16,976 

68,469 

15.179 

63,081 

March 

23,186 

93,556 

17,627 

71,954 

16.387 

67,673 

April    

-i    21,491 

88,071 

16,363 

67,069 

17,237 

70,880 

May 

-,    25,104 

100,056 

16,590 

68,355 

24,427 

96,409 

June 

-,    17,340 

70,561 

17,194 

70,988 

22,555 

92,174 

July 

■I    17,331 

70,523 

15,564 

58,551 

22,510 

91.955 

August 

■  1    17  766 

71,614 
72,963 

13.921 
11,497 

57,713 
47,746 

September- 

-     18,125 





October  . .-. 

-!    15,957 

65,813 

13,341 

55,046 

— 



November  - 

-'    17,882 

73,824 

14,021 

57,658 

— 



December  - 

.     17,570 

71,332 

15,042 

61,737 

'235,972 

955,635 

185.493 

755.985 

— 



Production  of  Gold  in  Western  Australia. 


Month. 

Export 
oz. 

Mint 
oz. 

Total 
oz. 

Total 
value 

Total,  1910  

363.496 

1,209.856 

1,573,352 

£ 

6,682,042 

January  1911  

17.463 
22.047 
12,296 
20,455 
22,076 
10,523 
15,334 

102,035 
84,991 
93,267 
91,791 
88,952 

106,464 
97,387 

119,498        507,592 

107,038        454,666 

March         

105.563        448.426 

112.246        476.787 

May            

111,028 
116,987 
112,721 

471,615 

497,188 

Tulv                  

478,805 

Other  Australasian  Gold  Production. 


Queensland 

New  South  Wales 

New  Zealand 

Victoria 


1909 


£ 

1,916,468 

869,546 

2,006,910 

2,897,340 


1910 


£ 

1,840,337 

803,727 

1,896,322 

2,422.700 


August 
1911 


£ 

134,275* 

70,320 

136,793 

190,894* 


1911 
to  date 


£ 

918,085* 
503.111 
1.218.159 
1.224.600* 


*  July  figures  only. 


Sale  of  Tin  Concentrate  at  Rkdruth  Ticketings. 


July 

July 

August         8, 

August       21, 

September  4, 


10,  1911. 
26.     „     . 


Tons 


213i 
254? 
222i 
268* 
220 


Value 


£25,019 
£28,484 
£25.632 
£30,109 
£25.262 


Average 


£ll7  6 
£lll  16 
£115  6 
£112  2 
£114  16 


Exports  of  Tin  and  Ore  from  Straits  and  Bolivia, 
Reported  by  A.  Strauss  &  Co. 


Metal  from  Straits  to  Europe 
and  America   

Metallic  Content  from  Bolivia 
to  Europe 


July  1911 
tons 

4555 

2332 


Aug.  1911 
tons 

4,675 

2,308 


191 1  to  date 
tons 

34.792 

13,313 


EDITORIAL 


IT  APPEARS  that  the  East  Rand  fiasco  is 
due  to  a  technical  difficulty,  not  unknown  to 
experienced  cyaniders.  For  instance,  a  refer- 
ence to  the  subject  will  be  found  in  the  re- 
port of  the  Rand  Central  Ore  Reduction  Co. 
for  the  year  ending  June  30,  1897.  During 
the  precipitation  of  enriched  solutions  a  floc- 
culent  substance  containing  gold  in  associa- 
tion with  zinc  cyanide  and  zinc  ferrocyanide 
was  carried  away  because  it  was  insoluble  in 
the  dilute  liquor  used.  The  sludge  that  col- 
lects at  the  bottom  of  sumps  and  other  re- 
ceptacles in  and  about  a  mill  ought  to  be  con- 
served and  tested.  In  a  very  large  mill  the 
accumulation,  however,  soon  becomes  em- 
barrassing, and  that  is  why  a  serious  loss  may 
occur.  Mere  bigness  is  not  always  an  advan- 
tage ;  even  consolidation  of  units  has  its  draw- 
backs. The  East  Rand  affair  suggests  that 
a  mining  and  milling  enterprise  may  become 
so  big  as  to  be  unwieldy  and  that  organiza- 
tion may  be  carried  so  far  as  to  militate 
against  efficiency. 


LAST  MONTH  we  omitted  the  '  Discus- 
sion '  department,  owing  to  lack  of  space. 
In  this  issue  we  give  a  large  instalment  of 
letters  commenting  upon  various  articles  that 
have  appeared  in  our  columns.  Such  letters 
are  heartily  welcome,  for  they  are  useful. 
Thus  the  valued  article  by  Mr.  Horace  V. 
Winchell  on  '  Prospecting  in  the  North  '  has 
gained  by  the  criticisms  of  Messrs.  W.  H. 
Emmons,  Charles  W.  Wright,].  M.  Moubray, 
and  R.  W.  Brock,  besides  the  original  writer's 
own  responses  to  his  critics.  The  highly  tech- 
nical contribution  on  '  Moisture  in  Tube- Mill 
Feed  '  by  Mr.  John  W.  Bell  has  elicited  com- 
ment that  has  given  fresh  point  to  the  first 
letter,  which  appeared  in  our  April  issue.  We 
hope  that  our  readers,  especially  the  busy  men 


who  lack  the  time  to  prepare  original  contri- 
butions, will  a\ail  themselves  of  the  oppor- 
tunity to  correct  any  error,  to  supplement  the 
information,  and  to  elucidate  the  ideas  appear- 
ing in  matter  contributed  to  this  Magazine. 
For  instance,  the  articles  on  the  '  Finance  of 
a  Mine  '  deal  with  a  subject  having  many  as- 
pects and  inviting  an  expression  of  diverse 
opinion.  The  author  of  them  will  undoub- 
tedly accept  fair  criticism  as  a  compliment. 
We  hope  that  this  suggestion  may  be  fruitful. 


AMONG  the  big  winnings  made  from  min- 
ing may  be  cited  the  story  of  Lord 
Randolph  Churchill's  investment  in  South 
Africa.  This  is  told  in  George  W.  Smalley's  re- 
cently published  '  Anglo-American  Memories.' 
When  Churchill  had  made  his  fatal  miscalcu- 
lation, by  "  forgetting  Goschen,"  and  resign- 
ing as  Chancellor  of  the  Exchequer,  his  for- 
tunes were  at  a  low  ebb.  Politically  he  was 
'  down  and  out,'  as  the  Americans  say,  and 
financially  he  was  in  a  bad  way.  He  decided 
to  go  to  Mashonaland  and  to  do  so  he  borrowed 
;^5000  from  his  friend,  Lord  Rothschild.  This 
was  in  1891.  That  most  sagacious  of  engi- 
neers, Mr.  Henry  C.  Perkins,  accompanied 
him  in  his  travels  and  on  their  return  they 
went  to  Johannesburg,  after  a  fruitless  search 
for  something  good  in  the  country  now 
called  Rhodesia.  At  Johannesburg  Mr.  Per- 
kins advised  Lord  Randolph  to  buy  the  shares 
of  mines  on  the  dip  of  the  Main  Reef  series. 
So  the  ;^5000  was  invested  in  the  shares  of 
Rand  Mines,  Ltd.  Needing  money,  he  soon 
sold  two-fifths  of  his  holding,  but  the  remain- 
der he  held  till  his  death,  when  it  brought 
^^70,000  and  helped  to  pay  his  debts.  For, 
as  Mr.  Smalley  says,  "  the  strain  of  frugality 
in  the  first  Duke  of  Marlborough  had  worn 
itself  out." 


170 


SEPTEMBER,    1911 


171 


ON  ANOTHER  page  we  discuss  Sir 
William  Ramsay's  lugubrious  prophe- 
sies of  the  starvation  and  disaster  that  are  to 
overtake  Great  Britain  175  years  hence.  Sir 
William  has  often  before  been  inaccurate  in 
his  facts  and  figures,  and  this  unscientific  at- 
titude of  his  mind  detracts  from  the  value  of 
his  views.  His  present  address  contains  at 
least  two  errors  of  calculation  and  statement 
that  go  far  to  mar  our  confidence  in  him.  For 
instance,  in  discussing  man-power  and  horse- 
power, he  quotes  the  case  of  a  Bhutanese  por- 
ter who  could  carry  230  lb.  and  his  own  weight 
of  170  lb.  up  a  hill  4000  ft.  high  in  8  hours  and 
asserts  that  the  man-power  is  equivalent  to  one 
twenty-fifth  of  a  horse-power.  On  working 
out  the  problem  we  find  that  he  does  injustice 
to  the  porter  by  150%.  The  energy  expended 
was400  X  4000=  l,600,000foot-pounds.  One 
horse-power  is  33,000  foot-pounds  per  minute 
or  15,840,000  foot-pounds  in  8  hours.  The 
man's  power  was  therefore  approximately  one 
tenth  of  a  horse-power.  Then  again  he  is  wide 
of  the  mark  in  stating  that  the  adoption  of  the 
steam-turbine  will  effect  an  enormous  saving 
in  the  consumption  of  coal  per  horsepower- 
hour,  his  figure  being  4  or  5  lb.  in  a  recipro- 
cating engine  and  1  or  1 J  lb.  in  a  turbine.  No 
doubt  some  second  rate  or  badly  managed  re- 
ciprocating engines  are  as  uneconomical  as  he 
suggests,  but  their  number  is  few,  and,  on  the 
other  hand,  it  is  certain  that  no  steam-turbine 
ever  gave  1  hp.  for  1  lb.  of  coal  per  hour  under 
practical  conditions  for  any  extended  period. 
Indeed  the  steam-turbine  has  only  a  short  lead 
on  the  best  reciprocating  engines.  We  cannot 
imagine  Huxley,  Darwin,  or  Spencer  making 
such  slipshod  blunders. 


for  his  sons  to  join  him.  We  hope  he  may  be 
successful,  if  only  to  spite  the  fates  that  have 
been  so  unkind  to  him.  Most  of  us  are  apt 
to  associate  the  marquisate  of  Queensberry 
either  with  pugilism  or  taxi-cabs.  Possibly 
Porcupine  may  supply  associations  even  more 
honourable.  Meanwhile  we  cannot  but  sym- 
pathize with  his  complaint  that  although  a  mar- 
quis he  does  not  sit  in  the  House  of  Lords,  be- 
cause his  title  being  Scotch  and  he  a  Radical 
his  peers  do  not  select  him  to  represent  them 
at  Westminster.  Again,  those  of  his  Radical 
friends  who  are  plebians  look  askance  at  him 
because  he  is  a  marquis.  Was  ever  a  man  so 
awkwardly  placed  !  Manifestly  he  has  chosen 
well  in  going  to  a  democratic  country  where  a 
career  is  open  to  talent  whether  to  marquises 
or  market-gardeners.  Possibly  at  Porcupine 
our  worthy  gold-miners  may  learn  to  forget 
that  he  is  an  ineffective  marquis  and  give  him 
credit  for  being  an  efficient  man.  We  warn 
our  Canadian  friends,  however,  not  to  put  the 
Marquis  of  Queensberry  on  the  board  of  direc- 
tors of  a  mining  company  until  he  has  served 
his  apprenticeship  as  a  miner. 


PORCUPINE  has  received  a  notable  re- 
cruit in  the  person  of  the  Marquis  of 
Queensberry.  He  left  for  New  York  on 
August  12,  on  his  way  to  the  new  goldfield  in 
Northern  Ontario,  and  before  starting  he  stated 
that  if  he  was  successful  there  he  would  send 


IN  THIS  ISSUE  we  publish  another  of 
the  series  of  articles  on  mining  finance. 
Mr.  Burnham  must  have  succeeded  already 
in  stimulating  intelligent  interest  in  a  subject 
the  technical  character  of  which  is  rendered 
of  the  greatest  practical  importance  by  its 
application  to  actual  practice.  All  his  con 
elusions  may  not  be  acceptable,  and  some  of 
them  may  appear  to  be  counsels  of  perfection, 
but  in  these  days  of  serious  mining  operations 
such  advice  is  surely  more  welcome  than  the 
counsels  of  imperfection  that  gave  so  low  a 
tone  to  the  moral  of  mining  speculation  twenty 
years  ago.  In  his  fourth  article  Mr.  Burn- 
ham  uses  the  Santa  Gertrudis  deal  of  the 
Camp  Bird  company  as  an  illustration  of  a 
risky  bit  of  finance,  especially  in  regard  to 
the  debenture  issue.  His  criticism  is  not 
rendered  useless  by  the  fact  that  the  deben- 


172 


THE    MINING    MAGAZINE 


tures  have  recently  been  retired.  As  regards 
the  allowance  for  a  persistence  of  the  orebody 
for  100  feet  below  the  deepest  level  and  the 
inclusion  of  this  block  of  ore  in  the  reserve, 
it  is  only  fair  to  say  that  the  development  of 
the  mine  has  confirmed  the  estimate,  although 
it  may  not  wholly  justify  the  risk  taken  by 
those  who  made  that  estimate.  Ore  not 
measurable  is  not  ore  that  can  be  measured. 
'  Probable  '  and  '  positive  '  are  not  the  same. 
Certain  distinctions  are  essential  to  sound 
business  in  mining  as  in  ordinary  affairs.  In 
this  case  the  expectations  were  fulfilled  and 
the  promoters  have  received  hearty  congratu- 
lations, but  Mr.  Burnham's  point  is,  we  take 
it,  that  the  Camp  Bird  incident  affords  a 
dangerous  precedent  and  is  one  not  to  be  fol- 
lowed on  its  merits.  We  must  not  eliminate 
hopefulness  in  mining ;  without  some  cheery 
optimism  the  industry  would  shrivel  and  dis- 
covery would  languish  ;  but  we  must  distin- 
guish between  the  things  hoped  for  and  the 
things  seen,  lest  our  footsteps  stray  into  those 
mirages  of  a  superheated  imagination  that, 
on  nearer  approach,  fade  into  the  barren 
sands  of  disillusionment. 


East  Rand  Proprietary. 

A  cablegram  from  the  Johannesburg  corre- 
spondent of  The  Financial  Times  antici- 
pated by  five  days  an  official  announcement 
that  something  had  gone  wrong  at  the  East 
Rand  Proprietary.  A  shiver  of  apprehension 
on  August  29  was  followed  on  September  2 
by  an  explanation  from  the  directors  of  the 
company.  Results  from  development  were 
poor  during  the  quarter,  therefore  a  rumour 
of  a  cut  in  the  dividend  was  not  in  itself  sur- 
prising and  did  not  produce  an  immediate 
effect,  but  the  official  circular  did.  It  appears 
that  the  amount  of  gold  deposited  by  precipita- 
tion and  accumulated  in  the  zinc-boxes  was 
found  to  be  short  of  the  estimate.  This  dis- 
crepancy, it  is  acknowledged,  had  been  noticed 
"  for  some  time  past,"  and  finally  became  so 


serious  as  to  call  for  a  special  investigation 
by    Mr.   W.   A.   Caldecott,   as  an   expert   in 
cyanidation.     He  confirmed  the  shortage,  and 
apparently  was  unable  to  suggest  a  satisfac- 
tory explanation.     For  none  is  given.     The 
directors  say  that  "  the  unrecovered  gold  will 
most   probably    be    lost."       This    is    merely 
cryptic.      A  simple  and  frank  statement  was 
urgently  needed.     The  gold   was   either  ex- 
tracted in  the  mill  and  has  been  stolen,  or  it 
never  was  extracted  and  a  radical  error  has 
been  made  in  the  calculated  recovery.     Such 
calculations  are  based  on  a  series  of  samp- 
lings and  assays.     The  ore  is  sampled  in  the 
stopes  underground  and  the  assays  are  re- 
corded on  a  large  map ;  the  pulp  discharged 
through  the  screen    of  the  stamp-battery  is 
likewise  sampled  and  assayed  ;  note  is  taken 
of  the  amalgam,  as  it  is  removed  periodically 
from  the  plates  ;  the  gold  contents  of  the  sand 
and  slime  in  the  vats  is  ascertained  ;  the  re- 
sidues from  each  are  tested,  as  well  as  the 
cyanide  solution  that  has  removed  most   of 
the  gold  ;  the  solution  circulating  through  the 
mill  is  known  as  to  quantity  and  gold  con- 
tents ;    finally    the    tailing    ejected   and   the 
water  escaping  from  the  mill  are  both  care- 
fully analysed.     Thus  by  check  and  counter- 
check, by  calculating  forward  and  backward, 
it   becomes  clearly   ascertainable   where  the 
gold  lies  and  how  much  of  it  must  be  col- 
lected in  the  precipitating-boxes,  which  con- 
stitute the  clean-up  department  of  a  cyanide 
plant.    As  some  mill-assays  are  made  hourly 
and  others  daily,  at  least,  it  is  impossible  that 
a  serious  discrepancy  could  go  long  undetec- 
ted.    The  matter  needs  an  explanation  more 
satisfying  than  any  yet  given.     We  are  in  a 
position  to  give  it. 

It  has  been  practically  acknowledged  that 
the  mill  "  for  seme  time  past  "  has  not  yielded 
as  much  gold  as  was  required  to  agree  with  the 
supposed  contents  of  the  ore,  but  that  the  differ- 
ence was  compensated  by  the  gold  held  in  re- 
serve, in  the  form  of  zinc  '  shorts,'  amalgam. 


SEPTEMBER,    1911 


173 


current  solution,  with  other  odds  and  ends, 
large  in  the  aggregate.  Probably  the  manage- 
ment hoped  to  redress  the  error,  but  it  be- 
came so  large  as  to  require  an  explanation 
that  might  obscure  or  minimize  the  damage 
done  to  the  reputation  of  the  company.  Un- 
doubtedly the  absence  of  a  satisfactory  state- 
ment aroused  fears  that  the  ore  being  mined 
was  not  up  to  the  grade  specified  in  the  esti- 
mate of  the  reserve  underground,  or  else  that 
the  stoping  width  had  been  increased  and  the 
grade  lowered  by  an  effort  to  maintain  the 
enormous  daily  tonnage  required  for  the  mill. 
But  we  have  information  indicating  that  the 
trouble  can  be  localized  in  the  mill ;  it  does 
not  concern  the  mine  or  its  resources.  We 
preface  our  diagnosis  by  explaining  that  the 
East  Rand  mill  has  been  in  a  state  of  con- 
struction for  three  years,  and  that  during  that 
time  the  incompleteness  of  the  equipment  has 
handicapped  operations  so  that  the  treatment 
has  lacked  the  perfection  desired.  Before 
the  plant  was  completed  it  was  crowded  with 
ore  beyond  its  capacity  and  it  has  been  a  con- 
tinual struggle  to  meet  the  requirem.ents  of 
the  mine  output.  Even  now  the  slime  de- 
partment is  10  vats  short,  so  that  the  tonnage 
crushed  has  to  be  reduced  from  200,000  to 
180,000  tons  per  month.  In  consequence  of 
this  overcrowding  of  the  plant  it  is  a  fact 
that  gold  has  been  lost  in  a  manner  not  alto- 
gether accountable.  The  loss  acknowledged 
is  put  down  at  ;^250,000. 

As  an  explanation  for  the  discrepancy  it 
has  been  suggested  that  the  loss  of  gold  was 
caused  by  the  '  fouling'  of  the  cyanide  solution. 
As  a  matter  of  fact  we  have  reason  for  stating 
that  it  is  due  to  something  analogous,  namely, 
the  loss  in  dissolving  power  due  to  lack  of 
aeration  of  the  solution.  To  non-technical 
readers  it  may  be  explained  that  a  cyanide 
solution  that  has  been  in  contact  with  the 
crushed  ore  will  cease  to  dissolve  further 
gold  after  a  certain  time,  and,  instead  of  dis- 
solving, it  will  begin  to  lose  gold  by  re-precipita- 


tion. The  gold  thus  precipitated  is,  strange  to 
say,  not  re-soluble  in  the  current  cyanide  so- 
lution, without  introducing  fresh  solution. 
This  gold  may  therefore  be  lost  in  the  final 
tailing  or  it  may  be  deposited  in  other  parts  of 
the  mill,  such  as  the  solution  and  storage 
tanks,  whence  it  is  finally  rejected.  It  could  be, 
and  it  should  be,  detected,  but  in  a  plant  that 
is  being  crowded  it  may  escape  through  pres- 
sure of  ordinary  routine  labour.  The  appar- 
ent remedy  is  to  cease  working  the  cyanide 
plant  at  over-capacity  and  to  make  additions 
such  as  will  facilitate  the  aeration  of  the  cya- 
nide solution,  for  fresh  oxygen  will  re- vitalize 
the  '  foul '  or  degraded  solutions  so  that  they 
become  again  effective. 

Whatever  official  explanation  or  apology 
may  be  forthcoming,  the  fiasco  is  a  serious 
shock  to  public  confidence.  The  East  Rand 
Proprietary  is  one  of  the  greatest  gold  mining 
enterprises  in  the  world,  it  has  been  recom- 
mended as  a  trustee  stock,  it  was  one  of  the 
few  mines  worthy  of  being  regarded  as  an 
'  investment.'  It  is  capitalized  for  ^2,500,000, 
and  its  market  price  has  dropped  ;^5, 600,000 
in  a  few  months.  The  decreased  market  value 
represents  lis.  or  2f  dwt.  per  ton  on  the  re- 
serve of  10,000,000  tons  of  ore.  Serious  as 
the  trouble  at  the  mill  may  be,  it  warrants  no 
such  exaggerated  depreciation.  It  has  been 
our  aim  to  lessen  the  perplexities  of  the  share- 
holders. They  must  not  permit  themselves 
to  be  stampeded.  The  East  Rand  Proprietary 
is  a  great  mining  property  of  proved  resources. 
Those  who  are  real  investors  should  sit  tight. 
After  the  disclosure  it  is  silly  to  throw  shares 
on  a  crumbling  market,  thereby  simply  play- 
ing the  game  for  those  who  have  started  a  bear 
campaign.  If  shareholders  can  get  news  of 
trouble  before  it  has  had  its  full  effect  on  the 
market,  they  might  profit  by  selling  their 
sharesand  re-purchasing  later,  but  this  they 
are  rarely  able  to  do  because  official  statements 
usually  appear  long  after  bad  news  has  leaked 
out.     East  Rand  shares  have  been  weakened 


174 


THE  MINING  MAGAZINE 


by  rumours  for  many  months.  It  has  been 
known  to  some  people  for  some  time  past  " 
that  things  were  radically  wrong.  Now  that 
everyone  knows,  it  is  useless  for  the  investor 
to  unload.  He  is  advised  to  wait  a  slow  re- 
covery to  a  figure  at  least  higher  than  those 
obtainable  during  a  panic. 


Prestea. 

The  information,  given  in  our  August  issue, 
that  all  was  not  right  at  Prestea,  has  proved 
only  too  true,  for  on  September  1,  after  an 
inkling  of  the  facts  had  depressed  the  shares 
for  several  days,  a  circular  was  issued  by  the 
secretary  of  the  company,  acknowledging  that 
the  output  of  the  mine  could  not  be  maintained 
at  more  than  15,000  tons  per  month  until  a 
new  incline -shaft  has  been  sunk  and  fully 
equipped.  Thus  not  more  than  half  of  the 
total  mill-supply  can  be  delivered  until  at 
least  another  year  has  passed.  The  directors 
appear  to  have  been  unaware  of  the  real  con- 
ditions, for  at  the  general  meeting  in  June 
Mr.  Edmund  Davis,  the  chairman,  stated  ex- 
plicitly that  the  110  stamps  would  be  fully  at 
work  by  the  end  of  the  current  year.  The 
letter  from  the  manager,  Mr.  E.  C.  Homer- 
sham,  compelling  this  revision  of  the  estimate, 
seems  belated,  having  regard  to  the  fact  that 
Mr.  Homersham  has  been  in  England  more 
than  a  month.  The  episode  has  a  sinister 
look.  The  Prestea  has  two  working  shafts ; 
one  is  equipped  with  5-ton  skips  and  another 
with  skips  of  2-ton  capacity.  Underground 
there  are  bins  capable  of  holding  2000  tons. 
Apparently  there  should  be  no  difficulty  in 
hoisting  1000  tons  per  day,  if  sufficient  labour 
is  available.  The  ore  is  from  9  to  10  feet 
wide  and  the  openings  extend  for  a  length  of 
5000  feet.  But  the  hard  quartz  lode  has  a 
casing  of  soft  graphitic  schist  ;  this  is  from 
18  to  24  inches  thick  and  may  lie  on  either 
wall,  and  sometimes  on  both.  When  moisture 
seeps  into  this  casing,  as  it  will  in  a  damp 
tropical  country  and  in  a  mine  having  many 


openings  at  surface,  the  ground  becomes  heavy 
and  great  care  is  required  to  prevent  falls  that 
impede  the  breaking  of  the  ore,  besides  being 
actually  dangerous  to  those  at  work  in  the 
stopes.  In  other  words,  this  mine  calls  for 
skill  in  supporting  ground  and  filling  excava- 
tions, but  presents  no  extraordinary  difficulty. 
And  whether  this  be  great  or  small,  it  should 
have  been  known  both  to  the  local  manage- 
ment and  to  the  London  directorate  many 
months  ago. 


Another  Cassandra. 

Things  in  general  appear  to  have  gone 
wrong  of  late.  International,  no  less  than 
domestic,  affairs  have  given  John  Bull  a  touch 
of  the  liver,  and  the  man-in-the-street  has 
come  to  the  conclusion,  like  Mr.  Mantalini, 
that  the  country  is  going  to  "  the  demnition 
bow-wows."  When  the  Moroccan  crisis  and 
the  railway  strike  had  reduced  the  average 
suburbanite  to  wondering  what  moment  was 
to  be  his  next  and  when  a  sweltering  summer 
had  taken  all  the  starch  out  of  the  most  arro- 
gant jingo,  even  a  Last  Ditcher,  there  comes 
the  final  stroke  of  malign  fate  in  the  shape  of 
vaticinations  by  Sir  William  Ramsay,  saying 
that  our  coal  supply  would  last  only  for  175 
years,  after  which  we,  or  our  descendents, 
must  "  look  forward  to  the  near  approach  of 
famine  and  misery."  Sir  William's  dicta  in 
other  matters  concerning  which  he  might  be 
expected  to  be  fairly  accurately  informed  have 
proved  incorrect  more  than  once  before,  and 
the  estimates  even  of  Royal  Commissions  on 
our  coal  supply  have  been  rendered  ridiculous 
also  more  than  once,  so  that  the  quotation  of 
the  one  by  the  other  should  impress  only  those 
too  weary  to  think  for  themselves.  We  mar- 
vel, indeed,  at  the  utter  lack  of  imagination 
exhibited  by  an  honoured  scientific  authority. 
A  period  of  175  years  at  the  beginning  of  the 
20th  century  contains  more  possibilities  than 
a  thousand  years  in  the  days  of  Job  ;  a  year 
of  modern  Europe  in  more  than  a  cycle  of 


SEPTEMBER,    1911 


175 


Cathay.  In  the  lives  of  many  now  Hving 
such  wondrous  deeds  have  been  done  in  the 
application  of  nature's  gifts  and  the  conquest 
of  the  energy  that  is  stored  in  rock,  water, 
and  air  has  proceeded  at  a  pace  so  accelera- 
ting that  there  seems  no  pressing  need  to  de- 
spair of  the  future  of  the  British  Islands  even 
when  the  coal  resources  are  measurable.  But 
they  are  not.  Sir  William  Ramsay's  premises 
are  not  to  be  taken  seriously.  He  bases  his 
facts  on  the  report  of  a  Royal  Commission. 
In  1871  one  of  these  ponderous  committees 
estimated  that  by  1900  only  85,000  million 
tons  of  coal  would  be  left;  thirty-four  years 
later,  despite  a  doubling  of  the  rate  of  output, 
another  Royal  Commission  (that  of  1905)  esti- 
mated the  visible  supply  at  101,000  million 
tons.  Both  of  these  Commissions  only  counted 
the  coal  above  4000  feet  deep,  but  the  second 
allowed  that  five  times  as  much  coal  existed 
below  4000  feet  as  in  the  ground  overhead. 
We  believe  that  man  can  go  deeper  than  any 
profitable  deposit  of  metallic  ore  yet  dis- 
covered ;  on  the  other  hand,  we  also  believe 
that  coal  strata  in  many  parts  of  the  world 
dip  deeper  than  man  will  ever  be  able  to 
penetrate,  yet  that  his  burrowing  will  be  suffi- 
ciently effective  to  extract  coal  two  miles  be- 
low the  sunlit  surface.  Such  deep  mining 
would  open  a  practically  illimitable  supply  of 
coal,  enough  to  postpone  Sir  William's  day  of 
famine  and  misery  to  the  Greek  kalends.  And 
if  for  the  sake  of  argument  we  suppose  that 
the  coal  of  Britain  is  finally  exhausted,  not  in 
175  years,  but  many  centuries  from  now,  are 
we  to  stifle  our  imagination,  refusing  to  see 
the  possibilities  of  oil,  of  alcohol,  of  electricity, 
of  sources  of  energy  to  be  discovered  by  scien- 
tific research  stimulated  by  the  desire  of  pro- 
fitable exploitation.  The  use  of  oil  as  a  con- 
centrated and  convenient  fuel  has  only  begun, 
yet  half-a-dozen  steamers  of  over  5000  tons 
each,  now  on  the  stocks,  are  to  be  equipped 
with  the  Diesel  oil-engine  ;  petrol  has  dis- 
placed coal    in   many   directions ;    alcohol   is 


made  from  various  substances  and  will  yet  be 
made  from  most  of  the  organic  rubbish  of 
creation;  electricity  has  not  reached  its  limita- 
tions, especially  as  regards  transmission  from 
long  distances.  Cheer  up,  gentlemen  !  Scien- 
tific invention  proceeds  by  geometrical  pro- 
gression. A  hundred  years  ago  there  was  a 
panic  in  England  because  the  supply  of  oaks 
threatened  to  be  insufficient  for  the  building  of 
ships.  A  hundred  years  hence  our  descen- 
dants will  smile  at  our  fear  lest  we  should  go 
bankrupt  foe  lack  of  coal.  Let  us  use  it 
thriftily  by  all  means,  beginning  at  Salisbury 
House,  where  scores  of  wretched  little  grates 
waste  as  much  coal  as  they  consume.  By 
all  means  let  us  use  our  coal,  but  with  due 
economy.  If  left  in  the  ground  it  benefits  no 
one ;  it  is  our  capital,  truly,  but  it  yields  no 
interest  if  unused.  Long  before  the  supply  is 
exhausted  our  descendants,  in  whom  we  place 
more  confidence  than  the  savant  at  Ports- 
mouth, will  have  learned  to  use  other  sources 
of  heat.  Till  then  let  us  avoid  the  chills  of  a 
premature  pessimism  and  the  damp  cold  of 
an  unintelligent  despair. 


The   Railway  Strike. 

The  recent  crisis  should  arrest  the  atten- 
tion of  all  thoughtful  men,  because  it  affords 
another  illustration  of  the  changing  relations 
between  employer  and  employee,  between 
capital  and  labour.  Those  of  us  who  have 
had  charge  of  mines,  especially  in  America 
and  Australia,  are  familiar  with  that  form  of 
industrial  paralysis  called  a  '  strike  '  and  we 
recognize  that  the  proper  understanding  of 
men  is  at  least  as  important  as  the  knowledge 
of  ore  deposits. 

The  dispute  originated  at  Liverpool,  where 
25,000  dock-labourers  had  been  dismissed  or 
*  locked  out '  by  the  leading  ship-owners  on 
August  14  in  consequence  of  the  failure  of 
the  men  to  carry  out  the  terms  of  an  agree- 
ment. Thereupon  the  Transport  Workers 
Federation  called  out   75,000   labourers  en- 


176 


THE    MINING    MAGAZINE 


gaged  in  the  carrying  trade  of  the  port.  This 
was  followed  by  a  strike  of  10,000  railway- 
workers,  also  at  Liverpool.  In  order  further 
to  accelerate  a  crisis  the  committees  repre- 
senting the  four  leading  national  railway- 
workers  unions  issued  an  ultimatum  on  August 
15  announcing  that  a  general  strike  on  aU 
railways  would  ensue  at  the  expiration  of  24 
hours  unless  their  demands  were  met.  The 
railway  managers  declined  to  make  any  con- 
cession. On  August  17  the  railway  service 
was  disorganized  in  many  parts  of  the  country 
by  men  refusing  to  work.  An  unprecedented 
situation  was  created.  Riots  and  sabotage 
proved  that  hooliganism  was  rampant  under 
the  cloak  of  labour  unrest.  The  Government 
immediately  called  a  conference  of  those  re- 
presenting the  warring  factions  and  on  August 
21a  provisional  settlement  was  reached,  by 
the  promise  to  appoint  a  Commission  em- 
powered to  enquire  at  once  into  the  grievances 
that  has  caused  the  outbreak.  \i  the  same 
time  the  Prime  Minister  undertook  to  enact 
such  legislation  as  might  be  necessary  to  give 
practical  effect  to  the  findings  of  the  Com- 
mission.    This  ended  the  strike. 

Of  course,  this  precis  of  a  complicated  series 
of  events  gives  but  a  bare  sketch  of  the  living 
energies  that  have  been  fiercely  at  odds.  Be- 
hind the  claims  and  counter-claims  of  the  rail- 
way companies  and  the  labour  unions  there 
exist  conditions  for  which  neither  is  wholly 
responsible  and  to  which  both  must  give  calm 
recognition.  Into  these  it  is  more  profitable 
to  enquire  than  into  the  merits  of  the  final 
quarrel  that  precipitated  the  strike.  In  the 
first  place,  the  railways  are  over-capitalized 
because  they  originally  paid  exorbitant  prices 
for  their  right-of-way  and  then  debited  cur- 
rent improvements  to  capital  account.  As  in 
British  mining,  the  ground  landlord  has  bur- 
dened a  public  utility  with  a  super-tax.  As 
in  mining,  development  has  often  been  charged 
to  capital.  Owing  to  State  regulation  it  is 
not  possible  to  levy  rates,  either  on  passengers 


or  goods,  such  as  will  redress  the  balance. 
The  railway  companies  pay  only  from  2i  to 
6%,  while  in  America,  for  instance,  with  more 
expensive  equipment,  no  better  management, 
and  lower  rates,  the  return  is  from  6  to  10% 
on  the  capital  invested.  The  only  direction 
in  which  earnings  can  be  increased  is  by 
economy,  especially  in  labour.  Hence  while 
the  cost  of  living  has  increased  about  10%  in 
the  last  decade  the  wages  of  railway -workers 
have  remained  stationary.  Even  this  does 
not  tell  the  whole  story,  for  averages  are  often 
misleading.  Among  the  railway-workers  of 
the  United  Kingdom  134,000  are  receiving 
20  shillings  or  less  per  week,  and  107,000 
earn  from  21  to  30  shillings  per  week.  Over- 
time is  usually  counted  after  12  hours.  A 
holiday  is  granted  after  10  years  service. 
These  facts  appear  to  excuse  dissatisfaction. 
But  the  men  cannot  complain  without  risking 
the  loss  even  of  a  precarious  livelihood.  Hence 
many  of  them — 1 16,214  in  the  principal  unions 
— have  formed  organizations,  the  leaders  of 
which  can  represent  them  in  making  com- 
plaints to  their  employers.  On  December  31 
1910,  the  total  of  persons  employed  on  the 
railways  of  the  United  Kingdom  was  608,750  ; 
hence  it  is  apparent  that  not  quite  20/o  of 
them  have  joined  the  unions.  But  it  is  also 
obvious  that  this  minority  is  sufficient  to 
cripple  the  railway  system  and  hobble  the 
business  of  the  country.  The  number  recently 
on  strike  is  estimated  to  have  been  200,000. 
It  remains  uncertain  whether  the  number 
would  have  increased  or  decreased  if  the  strike 
had  continued  a  few  days  longer.  Apart 
from  dissatisfaction  due  to  low  wages  and 
higher  cost  of  living,  the  men  complained 
that  the  Conciliation  Boards  formed  in  1907 
had  failed,  because,  among  other  reasons,  they 
could  not  be  represented  by  their  leaders. 
The  railway  managers  refused  to  recognize 
the  unions  or  the  officers  of  those  unions. 
On  the  side  of  the  managers  it  may  be  said 
that  they  were  willing  to  meet  their  own  em- 


SEPTEMBER,    1911 


177 


ployees  but  ignored  the  unions  or  any  other 
labour  representative  who  was  not  on  their 
pay-roll.  Obviously  labourers  are  rarely  good 
spokesmen  and  they  also  fear  to  appear  re- 
calcitrant, lest  this  should  lead  to  dismissal 
or  loss  of  promotion.  Hence  the  desire  to  be 
represented  by  a  skilful  pleader,  just  as  the 
railway  companies  themselves  engage  expert 
lawyers  to  speak  for  them  when  asking  for  a 
concession  from  Parliament.  The  refusal  of 
the  railway  companies — except  the  North- 
Eastern — to  recognize  the  unions  was  un- 
doubtedly the  prime  cause  of  the  strike,  for 
while  it  embittered  the  men  it  angered  their 
leaders. 

Thus  we  come  to  the  vital  question  of 
unionism.  Is  it  advisable  in  the  interest  of 
the  community  at  large — not  the  railway  com- 
panies or  the  railway  workers  only — that  the 
workmen  engaged  in  the  transport  system  of 
the  country  should  be  organized  ?  To  put  it 
plainly  :  is  it  best  for  the  public  that  these 
workmen  should  be  a  unit  or  a  mob  ?  We 
must  recognize  that  the  personal  relation  be- 
tween employer  and  employee  no  longer  ex- 
ists where  thousands  are  working  for  the 
agents  of  a  stock  company.  A  heterogeneous 
mass  of  men  is  working  for  a  corporation ;  as 
aggregates  neither  of  them  has  a  conscience 
or  a  sense  of  honour,  for  both  of  these  are 
personal  qualities  that  disappear  by  multipli- 
cation. Hence  the  bad  faith  and  inhumanity 
incidental  to  industrial  war.  The  employers 
are  organized ;  a  company  is  a  unit  of  em- 
ployers. These  companies  co-operate  and 
form  a  more  comprehensive  unit.  Why  not 
the  workmen  ?  We  believe  that  it  is  as  use- 
less to  decry  unionism  as  it  is  to  outlaw  com- 
petition ;  both  are  logical  developments  of 
that  modern  way  of  living  we  call  civilization. 
Accepting  the  fact  that  the  men  must  tend  to 
co-operate  in  self-defence  and  for  collective 
bargaining,  let  us  encourage  the  tendency  to 
the  point  where  it  becomes  useful  by  giving 
the  State  a  unit  that  is  tangible  and  controll- 


able. Let  both  the  employer  and  employee 
organize  so  that  the  contending  interests  are 
represented  by  responsible  committees.  In 
the  interest  of  the  public,  that  is,  the  country 
at  large,  it  is  desirable  to  end  the  savagery  of 
indiscriminate  strife.  Let  agreements  be  em- 
bodied in  contracts  secured  by  the  giving  of 
bonds  for  faithful  fulfilment.  Then  if  either 
side  proves  tricky  or  evasive,  the  issue  can 
be  tried  and  the  culprit  punished  in  terms  of 
pounds,  shillings,  and  pence.  A  member  of 
a  union  who  strikes  without  authorization 
should  be  liable,  at  least,  to  forfeiture  of 
membership.  At  present  the  men  are  in- 
clined to  keep  agreements  if  it  suits  them  and 
break  them  if  it  does  not,  on  the  principle  of 
Heads  I  win,  tails  you  lose."  The  com- 
panies accept  the  Conciliation  Boards  with  a 
tongue  in  their  cheek  and  neutralize  the  intent 
of  agreements  by  attention  to  the  letter  rather 
than  the  spirit  of  them.  Both  do  wrong  and 
both  need  to  be  brought  to  heel  by  the  State. 
The  public  is  the  final  arbiter  in  these  matters 
and  the  Government  is  the  executive  for  the 
public,  that  is,  the  country,  outside  the  parties 
to  the  industrial  contract.  The  desire  for 
social  justice  may  require  recognition  for  the 
workman"'s  union  as  for  the  employer's  com- 
pany, but  even  to  the  least  observant  it  is 
obvious  that  the  force  of  any  contract  between 
the  two  parties  is  impaired  by  the  fact  that 
one  of  them  has  property,  railways  or  fac- 
tories, vulnerable  to  attack  and  liable  to  de- 
preciation during  strikes,  while  the  other  at 
present  gives  no  hostage  for  fulfilment  of  his 
legal  promise,  claiming  recognition  for  his 
union  when  working  for  redress  of  grievances 
but  permitting  that  union  like  Pyrrhic  cavalry 
to  disappear  on  the  horizon  at  the  first  word 
of  retaliation  for  infraction  of  a  covenant  sup- 
posedly made  in  good  faith  by  the  two  oppos- 
ing interests.  Both  the  railway  companies, 
as  an  organization,  and  the  railway  workers, 
as  a  consolidated  labour-union,  should  give 
surety  for  carrying  out  their  agreements  with 


178 


THE    MINING   MAGAZINE 


each  other,  and  that  surety  should  be  a  sum 
of  money  large  enough  to  be  impressive,  with 
other  punishment  severe  enough  to  be  a  de- 
terrent. In  other  words,  let  us  employ  col- 
lectivism, whether  of  capital  or  labour,  as  a 
convenience  for  the  prevention  of  industrial 
anarchy  and  not  as  a  recurrent  menace  to 
civilization. 


Official  Valuation  of  Shares. 

We  publish  a  letter  from  a  correspondent 
who  appears  to  take  a  pessimistic  view  both 
of  the  mining  business  and  of  those  engaged 
in  it  ;  yet  his  forebodings  are  relieved  by  a 
suggestion  of  which  it  can  truly  be  said  that 
what  it  loses  in  practicability  it  gains  in 
humour.  He  takes  it  for  granted  that  the 
ordinary  reports  issued  by  mining  companies 
fail  to  be  illuminating  on  the  one  point  at 
issue,  namely,  the  value  of  the  mine  as  an  in- 
vestment. He  proposes  therefore  that  the 
medley  of  data  concerning  drifts  and  winzes, 
assays  and  drillings,  prospects  and  reserves, 
shall  be  supplemented  by  an  official  appraisal 
of  the  mining  property  and  an  inferential 
valuation  of  the  shares  among  which  that 
property  is  divided  for  market  purposes.  Un- 
doubtedly the  introduction  of  such  a  custom 
would  add  new  terrors  to  a  directorship  and 
might  even  put  a  wholesome  fear  into  the 
hearts  of  guinea  pigs  ;  in  any  case,  it  would 
impose  so  serious  a  responsibility  on  the  direc- 
tors of  mining  companies  as  to  lead  to  a  radi- 
cal change  in  their  status.  If  it  tended  to 
create  a  demand  for  the  professional  director, 
that  is,  a  man  specially  trained  and  specially 
qualified  for  such  work,  the  innovation  would 
receive  our  whole-hearted  blessing.  We  need 
in  mining,  as  in  all  forms  of  industrial  enter- 
prise, even  railways,  to  have  men  at  the  coun- 
cil-board who  have  had  the  training  and  ex- 
perience fitting  them  to  direct  complex  finan- 
cial and  technical  operations.  Mere  titles 
having  a  purely  social  significance  or  real  dis- 
tinction achieved  in   unrelated   pursuits  will 


some  day  cease  to  qualify  gentlemen  as  direc- 
tors of  public  companies ;  when  that  day  comes 
the   admiral,   the  general,   the  pro-consul  of 
empire,  will  be  expected  to  know  something 
of  mining  before  he  is  entrusted  with  the  task 
of  guiding  a  mining  enterprise.  Even  City  men 
of  the  glorified  jobber  kind  will  not  be  deemed 
the  best  for  the  purpose.     When  that  millen- 
nium arrives,  we  shall  see  the  boards  of  min- 
ing companies  strengthened  by  the  presence  of 
those  who  accept  the  occupation  of  a  director 
as  a  serious  avocation  for  which  due  prepara- 
tion will  have  been  made  by  the  systematic 
study  of  mining  and  finance,  supplemented  by 
an  apprenticeship  in  these  kindred  branches  of 
knowledge.     That  "  far  off  divine  event  "  is 
not  yet.     Before  we  ask  directors  to  appraise 
mining  properties  we  must  either  teach  them 
how  to  do  it  or  select  men  that  already  know 
how  to  do  it  efficiently.     It  may  be  granted 
that  in  some  cases,  as  in  the  Kolar  group  of 
gold  mines  or  the  equally  celebrated  group  at 
Treadwell,   it   would  be  practicable   for  the 
directors  to  give  the  shareholders  a  quarterly 
valuation  of  their  property,  and  hence  of  the 
shares  into  which  the  property  is  subdivided. 
In  these  two  instances,  at  least,  the  mines  are 
well  developed,  the  lodes  are  fairly  uniform  in 
character  and  persistence,  and — what  is  even 
more  important  for  the  purpose  in  hand — the 
directors  are  advised  by  consulting  engineers 
of  wide  experience  and  tried  capacity.     But 
all  lodes  are  not  uniform,  all  orebodies  are  not 
large  and  continuous,  all  consulting  engineers 
do  not  hold  the  complete  confidence  of  their 
directors.     On  the  contrary,  patchiness,  per- 
versity, and  non-persistence  are  as  character- 
istic of  most  ore  deposits  as  mutability  in  man 
or  mortality  in  mankind.     There  is  too  much 
of  the  .V  in  the  equation  to  permit  a  simple 
solution.       Take   the  Globe   &   Phoenix,  the 
Spassky,    the    Goldfield     Consolidated,    the 
Waihi,  the  Great  Cobar,  the   Dolcoath,  for 
example,  variously  rich  and  variously  promis- 
ing, and  ask  half-a-dozen  well  informed  men 


SEPTEMBER,    1911 


179 


to  appraise  them  :  the  results  would  be  more 
interesting  than  edifying.  If  the  best  informed 
specialists  could  not  make  an  accurate  ap- 
praisal, it  is  at  least  certain  that  the  directors 
could  not.  Before  such  a  difficult  task  is  put 
upon  them  it  will  be  necessary  to  re-consti- 
tute the  boards  of  most  mining  companies. 
Frankly,  we  like  the  idea.  It  is  one  to  play 
with  ;  if  not  to  conjure  with.  Think  of  the 
director  who  now  traffics  in  shares  being  com- 
pelled "  to  give  the  snap  away  "  by  stating 
openly  that  the  ^4  shares  are  only  worth  £l, 
or  that  the  £l  shares  are  worth  £\.  The 
privileged  speculator  who  now  sits  as  a  direc- 
tor would  have  to  distribute  his  information 
or  resign  from  the  board.  The  weary  share- 
holder would  skip  the  petty  details  about 
Level  No.  6  and  Winze  No.  5,  the  bewilder- 
ing array  of  widths  and  samples,  the  complexi- 
ties of  '  reduced  '  and  '  unreduced  '  assays,  the 
difference  between  sorted  and  unsorted  ore  ; 
he  would  have  eyes  only  for  that  pregnant 
paragraph  that  told  him  how  the  wise  men  on 
the  board  had  appraised  the  property  on  a 
given  date  at  a  given  sum  in  pounds  sterling. 
It  looks  too  good  to  be  true  ;  but  it  is  an  idea, 
possibly  an  ideal. 


Assays. 

At  a  meeting  of  the  Balcobo  Tin  Mines, 
the  chairman,  Sir  Cornthwaite  Kason,  gave 
an  account  of  his  visit  to  the  property,  which 
is  in  Spain.  We  referred  lately  to  the  un- 
satisfactory character  of  the  data  furnished  in 
the  prospectus.  The  recent  meeting  affords 
an  appropriate  sequel.  In  his  speech,  the 
chairman  said  :  "  With  regard  to  values,  I 
myself  took  three  samples  from  the  mine, 
which  were  sent  to  Johnson,  Matthey  &  Co., 
assayers  to  the  Bank  of  England,  for  assay." 
The  first  sample  was  of  concentrate,  in  a  bin  ; 
the  second  came  from  "the  lode;"  and  the 
third  "  was  of  pegmatite.  Of  which  material 
there  are  [so  said  the  chairman]  hundreds  of 
thousands  of  tons  there."     In  each  case  '  the 


produce  of  pure  tin  "  was  extraordinarily  high, 
the  three  assays  showing  62'5%,  66'5%,  and 
28'5%  metallic  tin.  The  weight  of  the  samples 
was  stated  but  nothing  is  said  concerning  the 
width  of  ore  across  which  they  were  broken. 
The  whole  performance  as  narrated  by  the 
chairman  was  a  farce,  likely  to  mislead  those 
who  are  not  experienced  in  mining.  Of  course, 
if  a  mere  Marquis  or  a  bluff  Admiral  had  been 
guilty  of  such  humorously  amateur  work  noth- 
ing much  might  be  said  and  the  episode  might 
be  treated  as  a  pathetic  kind  of  joke,  but  when 
a  gentleman  who  was  recently  Agent- General 
for  Western  Australia  and  presumably  knows 
a  little  about  the  rudiments  of  mining  goes 
through  such  a  performance  it  is  proper  to 
call  him  severely  to  account.  In  the  first 
place  Sir  Cornthwaite  Rason  ought  to  know 
that  it  is  much  easier  to  make  a  correct  assay, 
even  of  tin  ore,  than  to  take  a  sample  of  a 
lode.  He  ought  to  know  that  he  "himself" 
is  not  qualified  by  experience  to  do  so.  We 
deprecate  strongly  the  use  of  names  of  reput- 
able assayers  and  the  introduction  of  the  Bank 
of  England  into  a  statement  implying  that 
either  one  or  the  other  certifies  to  the  value 
of  the  ore.  They  simply  give  a  certificate 
proving  that  the  material  submitted  to  them 
for  assay  did  contain  a  certain  proportion  of 
metal.  They  do  not  certify  that  the  ore  came 
from  the  mine  mentioned,  although  that,  of 
course,  we  do  not  question,  or  that  the  few 
pounds  of  stuff  represented  any  tonnage  of 
similar  ore.  The  samples  sent  by  Sir  Corn- 
thwaite Rason  to  the  assayers  were  what  in 
practical  mining  we  term  grab  samples  or 
specimens.  Is  the  chairman  aware  of  his 
responsibility  when  he  asserts  that  there  are 
"  hundreds  of  thousands  of  tons  "  of  ore  aver- 
aging 28*%  tin  on  the  Balcobo  property?  I'n- 
published  reports,  based  on  inspection  by  en- 
gineers of  high  standing,  indicate  that  such  a 
statement  is  so  unwarrantable  as  to  merit 
severe  censure.  This  is  another  illustration 
of  the  harm  done  by  allowing  non- technical 


180 


THE    MINING    MAGAZINE 


persons  to  guide  the  public  in  technical  mat- 
ters. Furthermore,  it  should  draw  attention 
once  more  to  the  folly  of  assuming  that  skill 
in  politics,  in  diplomacy,  in  warfare,  in  gar- 
dening, or  in  tennis,  in  any  way  fits  a  man  to 
guide  the  highly  specialized  business  of  a 
mining  company. 


Indexes  of  Technology. 

From  time  to  time  attention  becomes 
directed  to  the  proper  indexing  of  current 
technical  literature.  The  subject  has  re- 
cently been  brought  to  our  attention  by  the 
completion  of  the  first  year's  issue  of  the 
monthly  bulletins,  containing  a  record  of 
articles  on  mining  and  metallurgy,  published 
by  the  International  Institute  of  Technical 
Bibliography,  of  Chancery  Lane.  We  do  not 
feel  called  upon  to  criticize  the  efforts  of 
other  publishers,  or  to  examine  in  detail  the 
value  of  the  results  achieved,  except  to  say 
that  though  the  indexes  are  compiled  by  well 
meaning  people,  they  fail  to  satisfy  either  the 
general  reader  or  the  expert,  in  that  they  are 
not  eclectic ;  in  other  words,  the  compilers 
are  not  specialists  and  therefore  are  not 
judges  of  the  current  or  permanent  impor- 
tance of  the  articles  included  or  omitted. 

The  adequate  codification  of  technical  know- 
ledge at  regular  intervals  is  an  object  so 
worthy  as  to  warrant  encouragement,  and,  to 
that  end,  we  think  it  right  to  define  our  own 
views  on  the  subject.  We  hold  that  it  is  im- 
possible to  index  all  mining  and  metallurgical 
literature  so  as  to  form  a  complete  record  of 
knowledge  and  progress.  It  is  only  the 
specialist  in  some  particular  branch  that  re- 
quires such  a  record,  and  as  a  rule  he  chooses 
to  do  his  own  searching,  and  to  form  his  own 
views  as  to  the  value  of  the  respective  articles. 
Besides,  a  specialist  makes  a  point  of  reading 
everything,  good,  bad,  or  indifferent,  for  even 
a  foolish  article  may  contain  points  for  him, 
and  a  three-line  filler  at  the  bottom  of  a  page 
may  prove  to  be  an  indicator  of  the   greatest 


service.  The  specialist  as  a  rule  is  well  able 
to  take  care  of  himself,  and  we  do  not  expect 
him  to  rely  on  indexes  prepared  by  people 
who  necessarily  know  less  of  his  particular 
subject  than  himself.  Having  thus  elimi- 
nated the  specialist,  we  have  only  the  general 
reader  to  consider.  By  him  we  mean  the 
intelligent  mining  engineer  or  metallurgist, 
who,  while  pursuing  for  himself  the  particu- 
lar study  connected  with  his  daily  work,  is 
desirous  of  being  fairly  well  informed  on  all 
the  subjects  connected  with  his  profession. 
It  is  on  this  basis  that  we  prepare  the  columns 
headed  Precis  of  Technology  and  Current 
Literature.  The  pages  devoted  each  month 
to  this  purpose  are  net  numerous,  but  we  ask 
our  readers  to  believe  that  articles  not  men- 
tioned have  given  us  almost  as  much  time  and 
consideration  as  those  that  receive  reference. 
In  other  words,  we  read  carefully  the  papers 
and  transactions  as  they  appear  in  print,  and 
the  omission  to  mention  many  that  have 
occupied  much  of  our  time  is  often  a  useful 
service  to  the  general  reader.  The  abstracts 
published  in  this  Magazine  are  not  done  by 
the  editor's  proverbial  instruments,  the  blue 
pencil  and  scissors.  They  are  all  written  by 
hand  after  the  abstractor  has  thoroughly 
assimilated  the  subject  matter,  and  usually 
they  contain  explanatory  information  in  ad- 
dition to  that  provided  by  the  author.  The 
work  is  done  by  those  who  have  a  direct  know- 
ledge of  the  subjects  and  are  capable  of  form- 
ing some  sort  of  jiadgment  on  questions  inci- 
dental thereto.  In  twelve  issues  these  pages 
reach  a  total  of  over  100,  enough  to  form  in 
themselves  a  yearbook  of  progress,  suitable 
for  permanent  preservation. 

The  average  indexer,  having  no  special 
knowledge,  usually  judges  the  importance  of 
an  article  or  paper  either  by  its  length  or  by 
the  beauty  of  its  illustrations.  As  a  rule  he 
does  not  take  cognizance  of  'leaders'  or  edi- 
torials,' though  these,  if  written  by  technical 
men,  may  contain  views  and  pronouncements 


SEPTEMBER,    1911 


181 


that  the  general  reader  and  the  specialist 
would  be  sorry  to  mrss.  Our  contemporaries 
occasionally  publish  articles  relating  to  some 
new  mining  district,  under  *  scare  '  headings  ; 
the  news  may  be  of  no  value  either  today  or 
a  hundred  years  hence,  but  by  the  virtue  of  a 
prominent  heading  such  writings  earn  places 
in  the  indexes  prepared  by  incompetents. 

Besides  the  general  reader  and  the  specia- 
list, there  is  a  third  class  of  customer  to 
whom  a  good  index  may  be  of  use.  We 
refer  to  the  beginner  or  'outsider'  who  hopes 
to  obtain  complete  information  on  some  par- 
ticular subject,  and  usually  expects  to  get  it 
for  "  about  eighteen  pence."  At  this  time  of 
day  nobody  can  expect  to  get  a  technical 
education  for  the  price  of  a  golf-ball.  Yet 
useful  information  was  never  so  cheaply  ac- 
quired as  today  ;  the  price  of  living  has  risen 
in  every  civilized  country,  but  the  cost  of 
recorded  knowledge,  whether  of  theory  or  of 
experience,  was  never  so  low.  For  half  a 
guinea  the  young  engineer  can  get  the  re- 
corded experience,  in  regard  to  a  special  sub- 
ject, of  a  past  master  ;  for  a  guinea  the  stu- 
dent can  purchase  a  compilation  equivalent 
to  a  course  of  lectures.  It  is  an  utterly 
worthless  volume  that  will  not  yield  informa- 
tion equal  in  value  to  that  of  the  retail  price 
of  the  book,  A  book  by  an  -experienced  spe- 
cialist will  afford  hints  worth  the  cost  of  a 
whole  edition.  No  thrift  is  so  wasteful  as 
that  of  the  man  who  foregoes  a  chance  to 
gain  the  advantage  of  accurate  knowledge. 
To  guide  him  in  that  pursuit  he  refers  to  in- 
dexes. To  be  useful  they  must  not  only 
have  passed  through  the  sieve  of  a  discrimi- 
nating reviewer,  but  they  must  be  correctly 
described.  We  confess  that  the  labours  of 
an  indexer  are  rendered  burdensome  by  the 
slovenly  selection  of  titles  on  the  part  of 
authors.  Articles  entitled  "  Some  Notes  on 
.  .  .  .",  or  "  General  Consideration  concern- 
ing ..  ,  .",  or  "  Recent  Observations  upon 
.  .  .  .",    might   as   well   be    paraphrased   as 


Random  Remarks  in  regard  to  .  .  .  .',  '\'ague 
Generalizations  about  ....',  or  '  Belated 
Ruminations  of  .  .  .  .'  Titles  should  be  de- 
finitive. '  Cyanidation  in  the  Transvaal '  is 
good  because  it  would  be  indexed  under  '  cy- 
anidation '  and  under  '  Transvaal,'  that  is,  a 
process  and  the  region  where  that  particular 
process  is  practised.  '  Geology  of  Broken 
Hill '  also  is  expressive,  for  it  relates  to  one 
scientific  subject  in  reference  to  a  particular 
mining  district.  This  is  better  than  *  Notes 
on  the  geological  structure  of  some  Broken 
Hill  mines,'  just  as  the  other  is  better  than 

Recent  progress  in  the  cyanide  process  at 
the  mines  of  the  Transvaal.'  A  title  should 
be  brief,  it  should  be  as  significant  as  brevity 
will  permit,  and  it  should  give  at  least  two 
salient  points  to  which  a  reference  may  be 
attached.  Unnecessary  words  should  be  ruth- 
lessly deleted.  Thus  the  article,  both  defin- 
ite and  indefinite,  may  well  be  omitted.  The 
Geology  of  Broken  Hill '  includes  an  un- 
necessary word :  the  definite  article  the,' 
which  is  valueless  to  the  indexer.  Similarly 
'  A  review  of  zinc  metallurgy '  coutams  one 
word  too  many  :  the  indefinite  article ;  for 
'  Review  of  Zmc  Metallurgy  '  suffices.  But 
these  may  seem  minor  points,  for  the  compe- 
tent indexer  often  entirely  ignores  the  title  of 
an  article  and  uses  his  own  judgment  as  to 
which  word  to  use  as  an  indicator  of  the  sub- 
ject discussed.  The  worst  blunder  is  the 
saddling  of  a  contribution  or  a  book  with  a 
title  that  is  misleading.  '  Four  weeks  in 
Mexico  '  conveys  nothing  regarding  the  tech- 
nical data  that  may  have  been  gathered  dur- 
ing that  period  ;  '  The  experiences  of  a  me- 
tallurgist in  Canada'  will  barely  stimulate 
even  a  lively  imagination;  'Mining  among 
the  Malays  '  may  relate  to  digging  for  gold 
tin,  or  rubies;  it  may  refer  to  the  placer 
operations,  lode  mining,  or  dredging  ;  it  may 
cover  a  barren  effort  or  a  profitable  experi- 
ence. Such  titles  are  only  aggravating,  es- 
pecially   to   the    indexer,  who,  like    the    re- 


182 


THE    MINING   MAGAZINE 


viewer,  asks  to  be  spared  from  reading  too 
much.  Enough  has  been  said ;  we  desire 
only  to  add  that  it  is  a  pleasure  to  index  the 
earnest  work  of  intelligent  men  and  we  regret 
no  trouble  that  may  be  entailed  in  the  pre- 
paration of  a  faithful  record  of  the  experience 
of  mankind  in  the  application  of  science  to 
mining. 


Buying  Prospects. 

Our  friend  the  editor  of  the  Mining  and 
Scientific  Press  has  had  something  useful  to 
say  regarding  the  buying  and  selling  of  '  pros- 
pects,' those  baby  mines  that  may  possibly 
grow  to  the  proportions  of  a  big  bonanza.  It 
is  notorious  that  the  appraisal  of  prospects  is 
difficult  and  the  acquisition  of  good  ones  is  rare, 
especially  by  operators  having  their  headquar- 
ters at  a  great  distance  from  mining  regions. 
At  a  time  like  this  when  a  new  gold-mining 
district,  such  as  Porcupine,  is  engaging  at- 
tention it  may  be  advisable  to  dwell  on  the 
subject.  Obviously,  if  a  London  syndicate 
sends  its  mining  engineer,  usually  a  man  well 
known  by  reputation,  to  look  over  the  ground 
with  a  view  to  business,  he  is  handicapped  by 
having  to  deal  with  local  people  who  know 
whom  he  represents  and  assume  that  being  the 
representative  of  capital  he  will  be  willing  to 
expend  it  lavishly.  Moreover,  the  owners  of 
claims  are  as  familiar  with  local  conditions  as 
they  are  sanguine  about  the  richness  of  their 
property.  The  visiting  engineer  lacks  the  time 
to  investigate  closely  and  to  bargain  deliber- 
ately. Hence  no  business  is  apt  to  result  or 
prospects  are  optioned  on  preposterous  terms. 
Another  method  is  that  by  which  owners  of 
claims  give  an  option  to  a  speculator  who  then 
comes  to  London  in  the  hope  of  inciting  the 
interest  of  persons  able  to  take  the  business 
off  his  hands  at  a  profit  to  him.  Twenty  years 
ago  such  a  visitor  from  the  other  side  would 
get  a  $50,000  option  on  a  mine  and  dispose  of 
it  in  London  for  ;;<r50,000,  returning  as  general 
manager,  being  thus  enabled  to  follow  a  san- 


guine report  with  further  hopeful  statements 
for  a  period  long  enough  to  enable  him  to  sell 
what  shares  he  had  been  allotted  at  a  hand- 
some premium.  Some  of  these  silly  things 
are  still  done  but  not  all  of  them  at  the  same 
time.  Nowadays  a  deal  is  not  consummated 
without  some  sort  of  inspection,  the  promoter's 
profits  are  less  lavish,  and  the  English  com- 
pany usually  has  sense  enough  to  choose  a 
manager  not  involved  in  the  flotation.  It  re- 
mains obvious  however  that  none  of  the  pro- 
cedure outlined  is  adapted  to  the  acquisition  of 
prospects,  which,  in  the  first  place,  do  not 
justify  a  large  expenditure  of  money  in  any 
form.  And  yet  it  is  just  such  business  as  allows 
the  handsomest  margin  to  anenterprisingfinan- 
cier  or  financial  group.  Another  and  better 
method  may  be  suggested.  The  London  people 
should  form  an  alliance  with  a  local  syndicate, 
the  latter  making  the  search  and  acquiring  the 
option,  and  then  turning  it  over  to  their  allies 
in  London,  on  the  basis  of  profits  to  be  equit- 
ably apportioned.  In  some  cases  it  may  be  ad- 
vantageous for  the  London  house  to  engage 
a  local  man  as  a  resident  agent  or  to  send  a 
tried  employee  to  reside  in  the  district  so  long 
as  business  seems  likely.  The  man  who  does 
business  in  a  hurry  is  at  a  disadvantage  when 
dealing  with  another  who  can  take  his  time. 
That  is  why  prospects  are  rarely  acquired  on 
terms  that  permit  expansion.  And  yet  in 
earlier  days  some  excellent  deals  were  made 
by  exploration  companies,  which  preferred  to 
buy  half  a  dozen  prospects  involving  small 
sums  instead  of  purchasing  the  assured  ore 
of  one  developed  mine.  If  we  may  hazard  a 
criticism  of  those  who  ought  to  know  their  own 
business  better  than  any  onlooker,  w-e  would 
say  that  the  syndicates  and  companies  devoted 
to  the  incubation  of  mining  enterprises  should 
strive  to  increase  the  efficiency  of  the  sifting 
process  involved  in  the  search  for  mines  by 
making  alliances  with  local  syndicates  or  by 
retaining  engineers  resident  in  such  localities 
as  present  a  chance  for  business. 


SPECIAL   CORRESPONDENCE 


News   from  our  own  Correspondents  at  the  principal  mining  centres 


CORDOVA,   ALASKA. 

Coal  and  the  coalfields  continue  to  be  the 
main  topic  of  conversation  in  Southern  Alaska. 
The  decision  in  the  Cunningham  case,  refus- 
ing patents  to  the  claimants,  is  considered 
here  to  have  been  essentially  a  political  ruling. 
Public  opinion  was  so  aroused  by  stories  of 
attempts  to  bottle  up  Alaska  in  the  interests 
of  the  Guggenheims  that  the  Department  of 
the  Interior  was  constrained  to  refuse  patents 
for  fear  of  popular  wrath.  At  least  that  is  the 
common  local  opinion.  If  it  be  correct,  it 
must  be  said  that  the  Cunningham  claimants 


tent,  the  character  of  the  roof  and  bottom, 
and  other  things  essential  to  planning  work- 
ings. Prospecting  drifts  have  been  driven 
but  no  real  attempt  to  mine  has  been  made 
prior  to  receiving  patent  to  the  ground.  This 
is  the  natural  and  business-like  way  to  pro- 
ceed ;  especially  in  a  far-off  country  such  as 
Alaska  where  transportation  must  be  pro- 
vided, and  markets  are  none  too  certain. 
The  Cunningham  claimants  proceeded  in  ac- 
cordance with  this  custom  but  the  point  being 
raised,  the  Commissioner  decided  that  the 
fact  of  no    mine '  having  been  opened  con- 


COKDOVA,   ALASKA. 


made  out  a  disappointingly  poor  case  as  a 
matter  of  law,  and  the  Government  had  better 
ground  for  cancelling  the  claims  than  had 
been  anticipated.  Under  former  conditions 
the  land  probably  would  have  been  patented 
without  objection,  but  in  Land  Office  pro- 
cedure many  things  are  passed  if  unques- 
tioned that  become  highly  important  once  ob- 
jection is  made.  The  more  significant  fact 
connected  with  the  decision  is  that  the  Com- 
missioner adopted  what  amounts  to  a  new  in- 
terpretation of  the  law.  The  statutes  require 
that  in  order  to  acquire  public  coal-land  the 
entry-man  must  have  opened  a  'mine.'  In 
practice,  it  has  been  customary  merely  to  face 
up  the  coal  to  determine  its  thickness  and  ex- 
3—3  183 


stituted  a  fatal  defect  in  title  and  refused  the 
patents.  This  amounts  to  a  ruling  that  there 
is  no  law  in  existence  under  which  coal-land 
can  be  taken  up  in  areas  and  under  conditions 
demanded  by  modern  industry.  It  is  a 
radical  step,  but  probably  represents  the  real 
facts.  It  puts  up  squarely  to  Congress  the 
duty  of  enacting  a  reasonable  and  modern  law. 
In  the  meantime  Congress  is  playing  politics 
and  Alaska  is  neglected. 

Mining  and  Politics. —  It  is  announced 
that  Walter  L.  Fisher,  Secretary  of  the  In- 
terior, accompanied  by  Alfred  H.  Brooks, 
chief  of  the  Alaskan  branch  of  the  United 
Steites  Geological  Survey,  W.  E.  Clark,  the 
Governor  of  Alaska,  and  other  ofikials,  will 


184 


THE    MINING    MAGAZINE 


visit  Katalla,  Cordova,  and  other  points  in  this 
part  of  the  territory  in  August.      Much  good 
is  expected  from  this  visit  since  Mr,  Fisher 
has  an  enviable  reputation  for  ability  and  fair- 
ness.    Alaska  has  had  little  to  blame  in  those 
Government  officials   and   others  who  have 
been  on  the  ground.    The  troubles  have  arisen 
from  misrepresentations  disseminated  by  non- 
residents.    While  the  coal-land   situation  is 
now   in   such   a    muddle    that    Congressional 
action  will  be  necessary  to  straighten  it  out, 
much    can    be    done    by    an    intelligent    and 
friendly  Secretary  of  the  Interior.    At  present 
things  are  at  a  standstill.     The  Cordova  & 
North  Western  railway  has  been  completed 
to  the  Kennicott  copper  mine,  but  no  line  has 
been  built  to  the  coalfields.     It  is  understood 
that  surveys  and  materials  are  ready  for  in- 
stant building  from  Katalla  Junction  when- 
ever the  Government  permits  a  mine  to  be 
opened.     The  Morrow  interests  are  applying 
for  patent  under  the  law  of  1908  and  there  is 
much  interest  in  the  question  whether  or  not 
their  claims  will  be  allowed.  As  that  law  only 
permits  entry  of  a  restricted  area,  2580  acres, 
and  includes  a  strong  anti-monopoly  clause, 
there  is  not  the  same  popular  objection  in  the 
States  to  giving  patents  under  it  as  under  the 
earlier  laws.     Mr.  Fisher  has  also  suggested 
that  the  Navy  open  a  mine  of  its  own  in  the 
coal-reserve.  This  would  relieve  the  situation 
in  part,  especially  if,  as  a  temporary  measure, 
surplus  coal  should  be  sold  to  local  dealers. 
It  will  be  remembered  that  in  the  Philippines 
the  Army  opened  a  coal  mine  and  later  with- 
drew from  the  general  market  when  private 
firms  were  prepared  to  supply.     At  present 
coal  costs  large  buyers  $9  per  ton  on  the  dock 
in  Southern  Alaska.     Retail  prices,  naturally, 
are  much  higher.      In  a  country  of  long  cold 
winters  where  wood  is  poor  and  none   too 
abundant,  this  imposes  a  real  hardship  on  the 
settlers,  especially  when  it  is  remembered  that 
excellent  coal  is  available  within  a  few  miles 
of  tide  -  water.      Passage  of  the  reciprocity 
agreement   with   Canada   should  reduce    the 
price  a  little,  but  not  much.    The  C.  &  N.W. 
Railway,  the  Beatson  Copper  Co.,  and  other 
enterprises  of  the  Alaska  Syndicate  are  plan- 
ning to  give  up  burning  coal  and  use  Califor- 
nian  oil.     This  can  be  delivered  at  a  cost  of 
$1  per  barrel  or  less  and  tanks  can  be  erected 
at  about  the  same  price.   In  view  of  the  higher 
efficiency   of    oil   and   the  great  economy   in 
handling  it,  there  would  seem  to  be  no  market 
among  larger  users  for  the  Alaska  coal  even 
when  mined.      Indeed,  engineers  figure  that 
Californian  oil  can  be  burned  to  advantage  in 


the  locomotives  that  will  haul  the  coal  to  tide- 
water. This,  however,  does  not  meet  the  prob- 
lem of  the  small  user,  of  the  tramp  steamer, 
or  of  the  Navy,  which  for  strategical  reasons 
seems  to  prefer  to  cling  to  coal  as  fuel. 

Petroleum  has  been  found  in  Alaska,  but 
the  immediate  prospect  of  developing  suffi- 
cient local  supply  is  not  brilliant.  At  Katalla 
about  six  years  ago  an  English  company  put 
down  fifty  or  sixty  holes,  found  considerable 
gas,  and  '  brought  in  '  five  or  six  wells.  These 
were  '  capped  '  and  as,  under  American  law, 
an  alien  corporation  cannot  receive  patent  to 
mineral  land,  the  property  was  sold  to  a  domes- 
tic corporation.  There  were  financial  compli- 
cations and  a  receiver  was  put  in  charge.  He 
leased  the  property  to  a  man  who  erected  a 
diminutive  refinery  and  laid  a  2-inch  pipe-line 
to  the  wells.  The  oil  proved  of  exceptionally 
high  gradeand  gasoline  was  made  for  a  flourish- 
ing local  trade.  Absence  of  suitable  harbour, 
the  small  scale  of  the  enterprise,  and  various 
other  complications,  prevented  the  growth  of 
the  industry. 

The  patent  area  was  small  and  the  sur- 
rounding lands  were  withdrawn  from  entry. 
This  spring  the  receiver  was  discharged  ;  it 
was  announced  that  contracts  had  been  made 
with  the  Standard  Oil,  and  that  the  field  was 
to  be  opened.  The  wells  were  uncapped  and 
pumping  was  begun.  It  promptly  became 
apparent  that  the  production  so  far  developed 
was  too  small  and  the  company  did  not  have 
money  for  further  drilling.  The  pay-roll  was 
not  met  and  the  whole  enterprise  was  closed 
down  again.  Probably  no  further  effort  will 
be  made  to  open  the  field  until  after  Congress 
shall  have  determined  on  a  policy  with  regard 
to  the  withdrawn  lands,  but  there  is  consider- 
able reason  for  thinking  that  a  valuable  oil- 
field will  ultimately  be  developed. 

Gold  prospects. — In  the  meantime  atten- 
tion is  being  centred  upon  prospecting  for  gold- 
quartz  veins.  These  have  long  been  known 
to  exist  in  the  mountains  that  fringe  the 
coast  but  no  one  has  ascertained  how  valuable 
they  are.  Alaska  is  a  hard  country  to  pros- 
pect. The  season  is  short  and  the  surface  is 
apt  to  be  covered  either  with  snow  or  a  damp 
layer  of  moss  and  scrubby  brush.  This  with 
the  absence  of  trails,  high  cost  of  supplies, 
and  few  opportunities  for  prospectors  to  re- 
plenish their  supplies  by  working  a  few  weeks 
for  wages,  has  hmdered  exploration.  In  1910 
there  was  an  unusually  long  summer  season. 
The  snow  melted  early  and  the  mountain 
slopes  lay  bare.  Railroad  construction  brought 
many  men  into  the  country  and  prospecting 


SEPTEMBER,    1911 


185 


flourished.  One  of  the  districts  brought  to 
the  front  at  that  time  was  McKinlay  Lake. 
This  is  situated  about  23  miles  from  Cordova 
and  about  three  miles  from  the  C.  &  N.W. 
railway.  It  is  accessible  both  by  railway  and 
launch.  Gold-quartz  veins  have  been  known 
there  for  a  number  of  years.  The  Lucky 
Strike  group  of  claims  was  acquired  by  a 
small  local  syndicate  headed  by  a  man  named 
Rice,  a  locomotive  engineer.  They  had  fair 
success  in  developing  their  property  and  found 
a  deposit,  variously  reported  to  be  diorite  or 
greywacke,  and  probably  the  latter,  some  40 
ft.  thick  and  full  of  stringers  of  quartz  carry- 
ing free  gold.  An  option  has  been  taken  on 
it  by  Stephen  Birch,  of  the  Alaska  Syndicate, 
and  J.  F.  B.  Erdlets  has  been  making  an  ex- 
amination. The  option  calls  for  $158,000  in 
payments  extending  over  18  months.  It  will 
cost  a  good  deal  to  sample  and  determine  the 
value  of  the  property,  but  if  the  ore  comes  up 
to  expectation,  $10  per  ton,  it  should  be 
cheaply  developed  and  worked.  Another 
property  that  has  been  recently  optioned  is 
that  of  the  McKinlay  Lake  Mining  Co.  This 
is  under  examination  by  C.  H.  Pearce,  for 
Bratnober  &  Lukach.  It  is  said  that  men 
affiliated  with  the  London  Exploration  Co. 
are  concerned  in  the  venture.  With  these 
exceptions  the  claims  are  in  the  hands  of  local 
prospectors  and  merchants,  who,  it  must  be 
said,  have  spent  money  liberally,  if  not  always 
advisedly,  in  attempting  to  determine  their 
value.  It  was  expected  that  this  season  would 
see  a  great  deal  of  prospecting.  Completion 
of  the  railroad  throws  out  of  work  a  large 
number  of  men  who  had  money  for  outfit  and 
grub.  The  snows,  however,  held  on  late,  and 
in  the  end  most  of  them  became  discouraged 
and  went  to  the  States.  At  Valdez  things  are 
more  active.  The  continued  success  of  the 
Cliff  Mining  Co.,  which  has  produced  $400,000 
and  paid  $60,000  in  dividends  on  an  initial 
investment  of  $25,000,  all  within  18  months, 
has  encouraged  everyone  to  work  on  his  claim. 
Naturally  the  veins  exposed  along  the  shore 
and  therefore  most  accessible  are  receiving 
most  attention,  but  along  the  glacier  and  up 
Mineral  creek  many  properties  have  not  only 
been  staked,  but  are  being  really  prospected. 
So  far  the  discoveries  are  of  quartz  veins 
carrying  free  gold.  Although  narrow  the  veins 
are  rich.  The  Cliff  mine  has  now  an  average 
of  11  inches  of  ore  in  the  slopes  but  the  mill- 
feed  is  running  about  $87  per  ton.  Three 
Nissen  stamps,  amalgamating  plates,  and  two 
Wilfley  tables  constitute  the  plant.  The  plates 
must  be  cleaned  every  day  and  require  con- 


stant care.  The  capacity  is  19  tons  per  day. 
The  vein  has  been  developed  to  a  depth  of 
250  ft.  and  stopes  opened  also  on  a  parallel 
vein  44  ft.  east.  Up  Mineral  creek  about 
six  miles  is  another  centre  of  activity.  Here 
B.  F.  Millard,  who  made  a  success  of  the 
Cliff,  has  just  paid  $100,000  for  a  three-quar- 
ter interest  in  the  property  of  the  Mineral 
Creek  Mining  Co.  With  him  are  associated 
George  B.  Harris  and  other  wealthy  Chicago 
men,  but  in  general  the  money  used  at  Valdez 
has  been  raised  locally.     The  community  has 


Port  of  Alaska. 

shown  a  commendable  disposition  to  back  its 
own  game  and  is  thus  exhibiting  the  same 
spirit  that  made  the  larger  Western  mines. 
Copper. — After  all  is  said  and  done  cop- 
per is  as  yet  the  big  resource  of  this  region. 
Three  mines  are  shipping  largely  and 
regularly.  The  Beatson  Copper  Co.,  on  La 
Touche  island,  is  sending  ore  steadily  to  the 
Tacoma  smelter  and  is  planning  a  concentra- 
tion mill  for  handling  the  low-grade  material. 
An  option  has  been  taken  on  the  ailjacent 
Barrack  Girdwood  property  and  a  drill  will 
be  set  to  work  in  an  effort  to  find  orobodies. 
W.  H.  Seagrave,  formerly  at  Ely,  Nevada, 
is  now  in  charge  and  has  made  many  improve- 
ments.    The  Ellemar  mine   is   shippuig  the 


186 


THE    MINING    MAGAZINE 


last  of  the  high-grade  ore  that  formed  the 
centre  lens  of  its  orebody.     This  was  made 
accessible  by  a  coffer-dam  built  around  the 
part  of  the  vein  that  is  covered  at  high-tide. 
This  particular  lens  of  ore,  10  to  15  ft.  thick, 
and  containing  roughly  10  to  12%  copper,  has 
been  worked  out  at  a  depth  of  600  ft.   Whether 
another  lens  will  be  found  is  uncertain,  though, 
in  the  opinion  of  engineers  who  are   familiar 
with  the  property  there  are  excellent  chances. 
The  Fidalgo,  Three  INIan,  and  other  proper- 
ties along  the  coast  are  continuing  develop- 
ments with  excellent  results.     The   Bonanza 
mine  at  Kennicott  is  so  far  making  good  all 
the  claims  of  its  most  enthusiastic  admirers. 
A  mine  that  ships  by  the  train-load  ore  contain- 
ing 71%  copper  and  19  oz.  silver  is  certainly 
a  wonder.     The  mine  produced  6,000,000  lb. 
copper  within  three  months  of  the   advent  of 
the  railway.     The  orebody  is  essentially  a  re- 
placement of  limestone  by  chalcocite.     The 
bed  thus  enriched  is  roughly  40  ft.  thick  and, 
as  a  result  of  faulting  along  an  anticline,  dips 
into  the   mountain.     It  has  been   developed 
continuously  250  ft.   below  the  outcrop  and 
shows  the  same  rich  ore.     At  present  the  low- 
grade  material   is  not  being   shipped   but   a 
mill  is  being  built  and   should   be   ready  for 
operation  in   October.      E.   D.    Emery,  who 
will  be  remembered  for  his  work  in  Mexico, 
is  in  charge.    That  there  are  other  big  proper- 
ties still  to  be  opened  seems  certain.     H.  A. 
Keller  has  been  examining  the  Mother  Lode 
mine,  the  supposed  continuation  of  the  Bon- 
anza,   for    New    York    men,    and     Stephen 
Birch  has  been  looking  at   the  properties  of 
the  Great  Northern  Development  Co.,  near 
mile  146.     M.  D.  Draper  is  in  charge  for  the 
Hubbard- Elliott  interests  a  little  farther  west, 
and  there  have  been  an  unusual  number   of 
experts  in  the  country  this  year  ;  all  of  which 
bodes  well  for  the  future. 

TORONTO. 

Porcupine.  —  The  earlier  reports  of  the 
fire  which  devastated  Porcupine  in  July  were 
greatly  exaggerated.  The  total  number  of 
deaths  so  far  ascertained  is  seventy-three,  and 
the  loss  of  property  is  estimated  at  $1,250,000. 
The  fire  covered  an  area  of  about  10  miles 
square  in  the  Porcupine  district,  and  had  no 
connection  with  the  less  destructive  calamity, 
which  some  days  earlier  destroyed  the  town 
of  Cochrane  about  30  miles  to  the  north.  The 
work  of  reconstruction  is  proceeding  as  rapidly 
as  possible,  though  considerably  delayed  by 
the  difficulty  of  procuring  timber  and  other 
building  materials.      Large  shipments  have 


been  going  forward  by  the  Temiskaming  & 
Northern  Ontario  Railway,  and  for  some  time 
there  was  much  difficulty  in  making  deliveries 
on  account  of  the  congestion  of  freight  on  the 
sidings.  Latterly,  however,  this  has  been 
overcome  and  things  have  been  running  more 
smoothly.  The  burned  towns  are  being  re- 
built in  a  more  substantial  manner,  and  build- 
ings of  a  better  class  will  replace  the  flimsy 
and  inflammable  structures  swept  away  by 
the  fire.  In  Porcupine  City  twenty  small 
buildings  have  been  erected  since  the  fire.  In 
South  Porcupine  some  business  houses  are 
preparing  to  erect  first  class  buildings  of  brick 
and  cement,  and  as  soon  as  material  can  be 
had  in  sufficient  quantities,  an  active  building 
boom  will  commence.  At  the  mining  camps 
also  the  new  buildings  will  be  of  a  more  sub- 
stantial type  than  those  destroyed. 

At  the  Hollinger,  reconstruction  is  proceed- 
ing steadily.     The  work  is  not  delayed  by  the 
difficulty  of  obtaining  timber,  as  the  company 
cuts-  its  own  supplies  at  the  mill  on   Miller 
Lake.     Foundations  for  the  compressor  and 
the  boilers  are  almost  completed  and  the  site 
for  the  mill  is  being  cleared.     The  Dome  has 
a  large  force  of  men  at  work  building  a  spur 
line  to  connect  the   mine  with   the  railway. 
The  fire  burned  the  overburden  on  the  south 
and  east  portions  of  the  property,  exposing 
bodies  of  quartz  and  schist,  which  are  con- 
sidered likely  to  add  to  their  available  ore- 
bodies.     Prospecting  will  be  undertaken  by 
test  pits.     At  the  West  Dome,  steel  and  con- 
crete fire-proof  buildings  will  be  erected.  John 
B.  Cleveland,  formerly  of  Arizona,  has  been 
appointed    manager    in    place    of  .Robert  A. 
Weiss  who  lost  his  life  in  the  fire.     The  Vi- 
pond  has  ordered  a  new  plant  comprising  an 
8-drill  compressor,  boilers,  and  a  hoist.     The 
main  working  shaft  is  to  be  put  down  to  200 
ft.,  and  cross-cuts  run  at  this  level  to  tap  No. 
2  and  No.  3  veins.     The  latter  is  18  ft.  wide 
at  the    100   ft.  level,  and  carries  high-grade 
ore.     The  Pearl  Lake  has  ordered  a  12-drill 
compressor  with  a  200  hp.  motor  to  run  the 
plant  with  power  from  the  Mattagami  river. 
A  new  vein  discovered  on  the  Dome  since  the 
fire,  18  in.  wide  with  a  good  surface  showing 
of  gold,  has  been  followed  into  the  Dome  Ex- 
tension   property    adjoining.       An   important 
strike    has    been  made  on  the  Jupiter,   now 
under    option    to   the    Drummonds,  the  vem 
which  was  encountered  in  cross-cutting  being 
4    ft.    wide    and    rich    in    native    gold.     The 
Mclntyre  will  put  in  a  stamp-mill  and  cyan- 
ide plant.     Shafts  are  down  on  the  north  and 
south  veins  nearly  200  ft.  and  cross-cuts  are 


SEPTEMBER,    1911 


187 


being  driven  between  them.  The  Rea  mine 
is  looking  well  at  the  200  ft.  level.  The  ore- 
body  has  been  followed  by  drift  for  100  ft. 
In  the  face  of  the  vein  4  ft.  wide,  native  gold 
runs  across  the  entire  width.  On  the  Crown 
Reserve  Porcupine  property  some  rich  ore 
has  been  found  at  the  50  ft.  level,  the  vein 
being  3  to  5  ft.  in  width.  A  vein  has  also 
been  discovered  coming  out  of  the  Hollinger 
property,  which  may  be  the  main  Hollinger 
vein.  The  American  Goldfields  have  decided 
to  begin  sinking  on  their  property  immedi- 
ately. The  Pike  Lake  in  the  Swastika  area 
has  a  wide  exposure  of  quartz  and  ankerite 
showing  much  native  gold.     Core  drilling  will 


Polenz,  of  Berlin,  acting  for  British  capital- 
ists, has  purchased  the  Christ  claims  in  Tis- 
dale  township  for  $235,000.  The  Routley 
claim,  near  Pearl  Lake,  has  been  bought  by 
Daniel  F.  Yost,  C.  A.  Burdick,  and  other 
New  Yorkers.  The  five  Davidson  claims 
in  Northern  Tisdale  have  been  sold  on  option 
to  interests  identified  with  the  Crown  Char- 
tered Co.  A  thorough  test  is  to  be  made,  and 
a  shaft  sunk  to  200  ft.,  and  if  satisfactory  re- 
sults are  obtained  the  sale  will  be  completed 
at  a  price  stated  to  be  $175,000.  John  C. 
Hicks,  of  New  York,  has  purchased  the  North 
Thompson  property  for  a  price  said  to  be  about 
$250,000.      The    McAulay-Brydge  property 


BEGIXNIXGS    OF    THE    HOLLINGER    MINE. 


be  undertaken  and  several  holes  put  down 
300  ft.  A.  H.  Brown,  who  installed  the  Co- 
niagas  mill  is  in  charge.  At  the  Lucky  Cross, 
another  Swastika  property,  two  promising  but 
narrow  veins  showing  gold  have  been  found. 

A  party  representing  the  Bewick-Moreing 
interests,  including  C.  A.  Moreing,  Sir  Wm, 
Bell,  Graham  Prentice,  W.  J.  Loring,  and  G. 
Lovell,  visited  Porcupine  about  the  end  of 
July.  It  is  understood  that  the  company  has 
undertaken  the  exploitation  of  52  claims  com- 
prising 2080  acres  in  Murphy  and  Wark  town- 
ships, belonging  to  a  syndicate  represented  by 
L.  S.  Colwell,  G.  T.  Hartt,  and  R.  Howard. 
More  recent  visitors  were  Louis  Reyersbach 
and  H.  F.  Marriott  of  London,  representing 
the  Wernher- Beit-Eckstein  interests. 

A  number  of  important  deals  in  Porcupine 
claims  have  lately  been  made.     Baron  G.  von 


in  Bristol  township  has  been  sold  to  B.  E. 
Cartwright  for  $500,000.  A.  D.  Miles,  con- 
sulting engineer  for  the  Dome  Mines,  has 
taken  an  option  on  the  Jowsey-W'ood  claims, 
seven  in  number,  in  the  Cripple  Creek  dis- 
trict, for  $250,000. 

Cobalt. — The  value  of  the  output  of  Co- 
balt can  no  longer  be  estimated  by  the  ton- 
nage of  ore- shipments  owing  to  the  increase 
in  the  proportion  of  concentrates,  and  in  the 
amount  shipped  in  the  form  of  bullion.  The 
tonnage  for  the  first  half  of  the  year  shows  a 
considerable  falling  oft' as  compared  with  the 
first  six  months  of  1910,  the  figures  being  re- 
spectively 11,978  and  14,868  tons,  a  decrease 
of  2890  tons.  The  value  of  the  ore  and  bul- 
lion shipments  on  the  other  hand  shows  a 
satisfactory  increase,  being  $7,972,333  for  the 
first  six  months  of  the  present  year,  as  com- 


188 


THE     MINING    MAGAZINE 


pared  with  $6,103,372  for  the  corresponding 
period  of  1910.     Nipissing  has  latterly  shown 
considerable  weakness  on  the  stock  market, 
owing  possibly  to  the  fact  that  the  profits  for 
the  half-year,  amounting  to  |858,891,  fell  be- 
low the  dividend  requirements  of  $900,000. 
This  is  easily  accounted  for  by  the  shortage 
of  power  early  in  the  season  which  curtailed 
the  output.      Prospecting  has  also  been  re- 
tarded   pending   the  installation    of    the    hy- 
draulic plant  with  which  it  is  proposed  to  re- 
move entirely  the  overburden  so  as  to  uncover 
every  surface  vein.     The  plant  will  comprise 
a  turbine  pump  with  a  capacity  of  4800  gal- 
lons per  minute  and  a  700  hp.  motor.     A  large 
area  of  the  property  remains  altogether  un- 
prospected.     The  work  is  expected  to  begin 
this  fall.     A  statement  as  to  the  company's 
condition  as  on  July  1  shows  cash  in  bank 
$803,205  ;    ore    in    transit    and    at    smelters 
$264,118;  ore  sacked  for  shipment,  $251,957  ; 
total  $1,419,230.     The  La  Rose  has  made  an 
important    strike  on    the    Princess    property 
where  ore  running  4000  oz.  to  the  ton  has 
been  struck  in  a  winze  sunk  from  the  235  ft. 
level.     The  vein  is  about  8  in.  wide.     The 
Violet  mine  owned  by  this  company  is  being 
again   worked   after    being  closed  for    some 
years.     A  statement  of  the  condition  of  the 
company  on  July  1   shows  cash  in  bank,  and 
valueoforeintransitandatsmelter  $1,184, 242; 
ore    sacked    for    shipment    $162,311,    total 
$1,346,553.     The  Coniagas  declared  a  divi- 
dend of  6%  and  bonus  of  3%  payable  August 
1,  making  in  all  27%  declared  so  far  this  year. 
The  Crown  Reserve's  report  for  the  half-year 
showed  a  production  of   1,582,994   oz.  silver 
of  a  net  value  of  $795,829,  and  a  profit  of 
$654,287.    Dividends  were  paid  to  the  amount 
of  $530,644,  being  30%  for  the  half-year.    The 
Rochester  has  let  a  contract  to  the  Lumsden 
Mining  Co.  to  explore  the  Rochester  location 
from  the  250  ft.  level  of  the  Lumsden  where 
a  4  in.  vein  of  smaltite  has  been  struck.     The 
Ophir  is  in  good  ore  in  two  veins  at  the  300 
ft.  level.     The  Trethewey  mill  has  been  over- 
hauled and  automatic  samplers  and  weighing 
machine  installed.      With   the   mill   treating 
2500  tons  per  month  there  is  ore  in  sight  for 
a  two  years  supply.     Prof.  W.  G.  Miller,  of 
the  Provincial  Mining  Department,  and  Cyril 
W.  Knight  are  making  a  further  study  of  the 
Cobalt  field  in  view  of  recent  developments, 
more  particularly  as  to  the  possibilities  of  ore 
continuing  in  the  diabase  formation.     In  the 
case  of  the  Temiskaming  mine  the  ore  in  the 
lower  levels  pinched  out  as  soon  as  the  Kee- 
watin  gave  place  to  the  diabase. 


Lake  of  the  Woods. — There  has  of  late 
been  a  marked  revival  of  interest  in  the  Lake 
of  the  Woods  gold  mining  district,  and  several 
formerly  productive  mines,  which  have  been 
closed  for  long  periods  are  again  working. 
At  the  Mikado,  where  operations  were  re- 
sumed a  year  since,  large  new  orebodies  were 
discovered,  and  15,000  tons  blocked  out.  The 
ore,  however,  proved  refractory  owing  to  its 
bismuth  content,  and  a  cyanide  plant  is  to  be 
installed,  operations  in  the  meantime  being 
on  a  limited  scale.  The  Ophir  mine  is  being 
successfully  worked  after  being  idle  for  20 
years.  The  shaft  has  been  sunk  to  100  ft., 
and  the  vein  carrying  good  gold  contents  has 
widened  at  depth  to  9  ft.  Drifts  are  being 
run  at  50  and  100  ft.  The  Black  Eagle,  also 
known  as  the  Regina,  which  has  been  idle  for 
three  years  and  has  extensive  workings  and  a 
good  equipment,  is  to  be  unwatered  and  ex- 
amined with  a  view  to  its  purchase  by  an 
English  syndicate. 

Porcupine. — The  market   for   Porcupine 
shares    has    latterly    been    dull    with    prices 
steadily  dropping.     In  addition  to  the  causes 
usually  assigned  for  depression,  including  the 
tightness  of  the  money  market  and  midsum- 
mer stagnation,  there  is  a  more  serious  reason 
for  the  slump.     Investors  have  been  rendered 
timid  by  the  unfavourable  report  on  the  dis- 
trict issued  recently  by  the  Ontario  Bureau 
of  Mines.     The  writer,  A.  G.  Burrows,  points 
out  that  the  Keevvatin  and  Huronian  forma- 
tions, which  contain  the  gold-bearing  veins, 
have  been  subjected  to  much  greater  meta- 
morphism  than  at  Cobalt.     The  occurrence 
of  gold  is  associated  with  the  quartz  solutions 
that  circulated  through  the  fissures.     Irregu- 
lar fissuring  has  produced  much  variation  in 
the  orebodies,  some  being  tabular  masses  of 
quartz  or  lenses  traceable  for  several  hundred 
feet ;  others  mere  veinlets  often  only  a  frac- 
tion of  an  inch  wide  and  a  few  feet  long.     The 
latter  variety  is  well  illustrated  by  the  fissur- 
mg  of  ankerite  bands  characteristic  of  many 
of  the  gold  deposits.      Irregular  and  lenticular 
quartz  bodies  having  a  width  of  10  or  20  ft. 
may  die  away  in  a  distance  of  50  ft.     Again, 
there  are  dome-like  masses  of  quartz  which 
are  elliptical  or  oval  in  surface  outline,  but 
whose   underground   extension  has  not  been 
examined  closely.      In   some  parts  at  least, 
these    masses   can  be  seen  in   contact  with 
underlying  rocks  at  a  low  angle,  which  would 
suggest  that  they  are  broad  lenticular  masses 
that  have  filled  lateral  fissues  in  the  country 
rock.     "  The  distribution  of  the  gold,"  the  re- 
port goes  on  to  say,  "  is  generally  irregular,. 


SEPTEMBER,    1911 


189 


occurring  along  one  or  both  walls,  while  other 
portions  of  the  vein  may  be  very  low-grade. 
Most  spectacular  showings  occur  on  many 
properties,  but  these  are  limited  to  portions 
of  the  veins.  Considering  the  irregular  char- 
acter of  certain  veins  and  the  quantity  of 
country  rock  which  will  need  to  be  mined, 
the  ore  must  be  considered  low-grade." 

JOHANNESBURG. 

Changes  in  the  Groups. — The  perpetual 
shuffling  of  the  personnel  of  the  various  min- 
ing groups  still  continues,  the  latest  changes 
being  those  that  have  just  taken  place  under 
the   Barnato  group.     W.   M.   Prout,  an  old 


first  part  comprises  the  recruiting  districts 
north  of  that  line,  namely,  Beira,  Chinde, 
British  Nyasaland  Protectorate,  German  South 
West  Africa,  Mozambique,  North  Eastern 
Rhodesia,  Fort  Jameson,  Nyasa,  Southern 
Rhodesia,  Zambesia,  Quilimane,  and  Tate. 
It  is  from  these  areas  only  that  an  increase 
in  the  native  labour  supply  can  be  hoped  for. 
Against  this  we  have  the  high  death-rate 
among  the  boys  that  come  from  these  dis- 
tricts, the  average  rate  being  about  80  per 
1000  per  annum.  The  district  south  of  lat. 
22°  comprises  Basutoland,  British  Bechuana- 
land.  The  Cape,  Natal,  Zululand,  Orange 
Free   State,   Swaziland,  and   the  Transvaal. 


A    DECANTATIOX    PL  AST    ON    THE    TiAXD. 


servant  of  Barnato  Bros.,  leaves  the  Wit- 
watersrand  Gold  Mining  Co.,  his  place  being 
taken  by  A.  White,  who  was  assistant  con- 
sulting engineer  to  J.  G.  Lawn.  R.  Clark- 
son  also  leaves  the  New  Primrose,  his  place 
being  taken  by  H.  Van  Eyssen,  late  of  the 
East  Rand  Proprietary.  The  Rand  Mines 
has  made  a  small  change,  in  that  it  now  ap- 
pears to  have  dispensed  with  a  sand-filling 
expert.  Edgar  Pam,  who  held  that  position, 
has  been  appointed  a  sectional  manager  on  the 
Geldenhuis  Deep,  M.  O.  Tillard  having  left 
that  mine  and  taken  a  position  as  sectional 
manager  on  the  Nourse  Mines. 

Native  Labour. — This  is  the  most  impor- 
tant question  facing  the  local  mining  industry. 
There  is  a  serious  shortage  of  native  labour. 
Africa,  from  a  recruiting  point  of  view,  is  di- 
vided into  two   parts  by  latitude  22°.     The 


These  are  practically  drained,  in  so  far  as  any 
increase  of  supply  is  concerned.  The  aver- 
age death-rate  of  natives  from  these  areas  is 
about  30  per  1000  per  annum. 

The  average  number  of  natives  employed 
in  all  mines  and  works  in  the  proclaimed  la- 
bour districts  of  the  Transvaal  isabout  2 1 8,000. 
Of  this  number  about  193,000  are  recruited 
from  the  districts  south  of  lat.  22°  and  the 
remaining  25,000  from  the  northern  districts. 
Owing  to  the  high  mortality  among  the  latter, 
the  Government  will  probably  stop  further 
recruiting  unless  the  mines  can  show  healthier 
conditions.  To  this  end  rules  have  already 
been  framed  making  it  compulsory  for  all 
these  natives  to  use  a  proper  change- house 
and  baths,  and  to  go  from  the  change-house 
to  the  shafts  in  covered  ways,  etc.  The  ques- 
tion remains  whether  all   this  e.xtra  trouble 


190 


THE    MINING    MAGAZINE 


will  decrease  the  mortality.  It  seems  un- 
likely. In  the  first  place  it  is  of  little  use 
trying  to  take  care  of  natives  when  they  do 
not  understand  how  to  look  after  themselves. 
Generally  speaking,  the  mortality  of  all  natives 
due  to  disease  is  about  30,  and  half  of  this, 
that  is  15  per  1000  per  annum  is  due  to  pneu- 
monia, while  phthisis  accounts  for  another  5. 
The  death-rate  from  accidents  is  about  3  per 
1000,  so  that  the  total  death-rate  from  all 
causes  is  33  per  1000.  With  regard  to  the 
natives  from  the  north  of  lat.  22°,  while  they 
are  suited  for  work  in  the  hot  rarefied  atmos- 
pheric conditions  of  the  Tropics,  they  cannot 
be  acclimatized  to  the  conditions  of  the  Rand. 
This  is  an  important  point  and  must  not  be 
overlooked.  No  matter  with  what  care  the 
Tropical  native  is  treated  on  the  Rand,  only 
the  fittest  will  survive  the  severe  climatic  con- 
ditions with  their  great  variations  in  tempera- 
ture. 

Government  Training  School.  —  The 
Government  school  for  the  training  of  miners 
was  officially  opened  last  month  at  the  Wol- 
huter  gold  mine,  Johannesburg,  where  pro- 
vision is  made  for  50  apprentices  under  the 
following  conditions : 

(0    Youths    selected    to    undergo   a   general 
course    of   underground    training ;    they 
must  be  of  first-class  physique  and  pass 
a  rigorous  medical  examination. 
(2)  No  person  under  17  years  of  age  or  over 
25  years  of  age  shall  be  allowed  to  under- 
take such  course. 
{3)  An  agreement  with  the  committee  bind- 
ing  him   to  work  for  a  period  of  three 
years  underground,  in  consideration  of  a 
progressive  wage,  shall  be  entered  into 
on  behalf  of  the  apprentice. 
(4)  The   three  years  course   shall  comprise, 
amongst   other    matters,    the    following 
underground  work :   (a)   Timber  Work  ; 
(b)   Pipe  and  Plate-Laying  ;  (c)  Pumps  ; 
(d)  Hand-Drilling;  (e)  Machine-Drilling; 
if)  Ambulance  ;  (g)  General  Mine- Work. 
The  time  to  be  occupied   on  each  of   the 
above   branches   of   work  and   the   order   in 
which    each   branch,  with    the  exception  of 
machine-drilling,    is    to  be   taken,   shall    rest 
with  the   discretion   of   the   instructor.     The 
application  form  and  draft  indenture  are  pub- 
lished for  general  information,  and  all  appli- 
cations are  to  be  addressed  to  the  Chief  In- 
spector of   Mines,  Johannesburg.     The   fol- 
lowing certificates  are  to  be  attached  to  the 
application   form  :    (/)  a  medical  certificate, 
especially  in  respect  of  the  condition  of  the 
applicant's  lungs;  (2)  a  certificate  of  character, 


from  a  magistrate,  justice  of  the  peace,  clergy- 
man, or  other  responsible  person. 

This  excellent  scheme  has  therefore  at  last 
been  put  into  execution  by  the  Governm.ent 
in  conjunction  with  the  direction  and  manage- 
ment of  the  Wolhuter  gold  mine.  A  portion 
of  this  mine  has  been  handed  over  and  will 
be  run  entirely  by  the  students  under  the  per- 
sonal supervision  of  one  of  the  foremen.  The 
success  or  otherwise  of  the  scheme  will  de- 
pend upon  the  students,  of  whom  there  are  at 
present  about  30,  and  in  turn  their  keenness 
for  the  work  will  depend  on  the  capacity  and 
enthusiasm  of  their  instructors.  The  students 
will  receive  pay  ranging  from  4s.  3d.  per  day, 
at  the  commencement  of  the  course,  up  to 
6s.  9d.  for  the  last  three  months  of  service ; 
out  of  this  he  will  pay  £3.  5s.  per  month  for 
board  and  lodgings,  7s.  for  medical  attendance 
and  benefit  society,  and  Is.  for  the  reading- 
room,  making  in  all  £3.  13s.  per  month,  which 
leaves  a  margin  of  £l.  13s.  3d.  for  pocket 
money,  on  a  basis  of  25  working  days  per 
month  at  the  minimum  rate  of  4s.  3d.  per 
day.  It  will  be  interesting  to  see  what  class 
of  students  will  avail  themselves  of  this  oppor- 
tunity of  obtaining  a  cheap  and  excellent 
training.  I  am  inclined  to  think  that  25  as  a 
maximum  limit  for  the  age  of  the  entering 
student  is  too  high,  and  that  it  would  have 
been  better  to  have  made  it  21  years. 

Brakpan  and  Van  Ryn  Deep. — These 
two  mines  are  situated  next  to  each  other  in 
the  Far  East  Rand.  The  Van  Ryn  Deep  is 
on  the  first  row  of  deep-levels,  and  the  Brak- 
pan is  a  second  '  deep  '  below  it.  Brakpan 
recently  started  milling,  and  its  ore  reserve 
on  ]\Iay  31  was  as  follows  :  Payable  2,035,108 
tons,  averaging  6"62  dwt.,  about  69%  of  the 
total  tonnage  developed;  unpayable  876,671 
tons,  averaging  2' 16  dwt.,  about  31%  of  the 
total  tonnage  developed.  These  tonnages  are 
calculated  over  an  average  stoping  width  of 
522  inches.  From  these  figures  it  would  ap- 
pear, assuming  the  removal  of  10%  by  sort- 
ing, and  allowing  for  an  assay-factor  of  90% 
and  an  extraction  of  95%,  that  the  probable 
return  per  ton  of  ore  milled  will  be  about  24s. 
With  a  new  mine  just  starting  the  probable 
cost  per  ton  milled  should  be  about  20s., 
leaving  a  margin  of  4s.  per  ton  as  profit. 

The  Van  Ryn  Deep  for  the  first  time  gives 
an  estimate  of  the  ore  reserve  in  the  quarterly 
report.  The  figures  are  as  follows:  365,165 
milling  tons  of  payable  ore  averaging  6*6  dwt. 
and  119,800  tons  of  unpayable  ore,  averaging 
272  dwt.  From  this  it  would  appear  that 
the  Van   Ryn   Deep  and  Brakpan  mines,  so 


SEPTEMBER,    1911 


191 


far  as  development  has  gone,  are  in  an  area 
having  a  fairly  consistent  value  of  about  6'6 
dwt.  throughout.  At  the  Van  Ryn  Deep  the 
lode  has  been  located,  by  means  of  a  bore- 
hole, south  of  the  big  fault,  which  has  a  down- 
throw of  about  400  feet. 

The  first  returns  for  a  complete  month  have 
been  published  by  the  Brakpan.  The  yield 
per  ton  milled  during  July  was  much  higher 
than  the  average  anticipated,  being  31s.  9d.  as 
compared  with  24s.,  £nd  the  profit  was  9s.  1  Id. 
Apparently  efforts  have  been  made  to  give  the 
mme  a  cheerful  start  by  picking  some  good 
ore.  But  there  is  probably  another  explana- 
tion of  the  high  figures,  namely,  that  the  gold 
recovered  during  the  days  in  June  when  the 
mill  commenced  crushing  has  been  included 
in  the  returns,  though  the  tonnage  of  ore 
treated  was  not.  It  will  be  interesting  to 
watch  the  future  fall  in  grade  and  also  a  pos- 
sible reduction  in  cost.  The  extraction  during 
June  was  reported  at  only  19s.  lid.  per  ton,  a 
low  figure  due  to  absorption  of  gold  by  the 
amalgamating  plates  and  the  cyanide  plant. 
The  plates  usually  receive  unnecessary  blame. 
In  reality  it  can  be  taken  that  a  plate  12  by 
5  ft.  will  not  require  more  than  20  oz.  left  on 
it  after  the  first  month's  working.  At  Brak- 
pan there  are  30  plates,  so  the  absorption 
would  be  about  600  oz.,  worth  ^2520.  At 
least  half  this  amount  could  be  removed  at  the 
end  of  the  second  month,  if  required. 

Education  of  Mining  Engineers. — The 
discussion  on  the  education  of  engineers  that 
took  place  recently  at  the  Institution  of  Civil 
Engineers  in  London  has  attracted  attention 
on  the  Rand.  Judging  by  my  own  experience 
here  I  am  inclined  to  think  it  best  for  a  youth, 
after  passing  a  preliminary  university  examin- 
ation such  as  matriculation,  to  go  straight  to 
a  two  years'  apprenticeship  with  a  home  firm 
of  engineers  and  have  the  run  of  a  mine  or 
colliery.  Thus  he  would  learn  the  mechanical 
and  practical  details,  and  his  suitability  for 
this  branch  of  occupation  would  be  tested  be- 
fore embarking  on  a  long  period  of  expensive 
education.  A  youth  thus  made  familiar  with 
the  problems  to  be  solved  would  appreciate 
the  lecture  courses  in  quite  a  different  way 
from  one  straight  from  school.  At  the  present 
time  all  that  is  done  in  London  for  the  prac- 
tical instruction  of  students,  as  far  as  the 
Rand  is  concerned,  is  the  appointment  of  eight 
of  the  most  successful  answerers  of  examina- 
tion papers  to  a  year's  post-graduate  course 
out  here.  It  is  a  sufficiently  well-known  fact 
that  success  at  college  does  not  necessarily 
mean  success  in  the  handling  of  the  serious 


problems  of  mines.  We  want  more  young 
men  that  have  stood  the  test  of  practical  work 
before  coming  here.  There  is  a  scarcity  of 
English  educated  engineers  on  the  Rand  and 
the  indications  are  that  the  young  Dutchman 
who  grows  up  in  the  mining  districts  and 
understands  from  his  earliest  years  what  will 
be  his  responsibilities  will  gradually  beat  his 
English  rivals.  This  change  is  not  very  ap- 
parent as  yet,  but  it  will  nevertheless  come  in 
time,  and  a  ministry  with  Dutch  sympathies 
would  naturally  favour  any  proposition  to  help 
forward  the  aspirations  of  the  Dutch  race. 
Something  more  is  therefore  required  at  home 
in  order  that  the  young  English  mining  en- 
gineer shall  be  practically  and  scientifically 
educated  if  he  is  to  hold  his  own  in  South 
Africa. 

SAN  FRANCISCO. 

Goldfield,  in  Nevada,  has  been  in  danger 
of  becoming  known  as  a  one-mine  district. 
The  magnificent  output  and  excellent  tech- 
nical work  that  has  characterized  the  record 
of  the  Goldfield  Consolidated  Mines  Co.  has 
so  monopolized  attention  that  other  properties 
in  the  district  have  received  little  attention. 
This  tendency  has  been  all  the  stronger  since 
the  collapse  of  the  wild  orgy  of  speculation 
that  characterized  the  discovery  of  the  dis- 
trict. It  has  been  recently  estimated  that 
when  the  bubble  burst  there  were  over  300 
Nevada  companies  organized  on  the  one  mil- 
lion share  basis  and  engaged  in  distributing 
stock  to  an  eager  public.  Most  of  them  had 
no  substantial  assets,  a  large  number  being 
founded  on  a  mere  option  to  purchase  unpro- 
spected  ground.  In  many  cases  the  shares 
of  such  companies  sold  on  a  basis  that  in- 
volved payment  of  1 1,000,000  for  small  areas 
of  wholly  unproved  value.  So  long  as  money 
was  plentiful  and  speculation  rife,  the  good 
shares  carried  the  bad  and  money  was  promptly 
forthcoming.  Such  a  condition  could  not 
last  and  in  the  end  resulted  in  large  tracts 
resting  in  the  hands  of  impecunious  companies 
unable  to  go  ahead  with  development  and  un- 
willing to  sell  at  any  reasonable  figure.  At 
Goldfield  there  is  a  large  area  of  ground  that 
will  warrant  reasonable  expenditures  for  pro- 
specting but  the  work  must  be  carefully  done 
and  there  is  no  assurance  of  fabulous  returns 
in  any  particular  case.  Attempts  are  now  to 
be  made  by  at  least  two  responsible  concerns 
to  develop  deeper  ground  w4iere  shallow  work 
has  shown  promise.  The  Goldfield  Deep 
Mines  Co.  has  been  formed  to  sink  on  ground 
belonging  to  the  Goldlield  Merger  Mines  Co. 


192 


THE     MINING     MAGAZINE 


Essentially  this  is  an  attempt  to  test  in  depth 
veins  known  to  be  rich  in  the  Goldfield  Con- 
solidated mine  and  which  dip  out  of  the  terri- 
tory belonging  to  that  company.  A  shaft 
2000  ft.  deep  is  planned.  Backing  the  new 
enterprise,  among  others,  are  George  Wing- 
field  of  the  Consolidated  and  W.  A.  Clark, 
whose  interest  was  enlisted  through  the  ne- 
cessity of  providing  freight  for  the  Las  Vegas 
&  Tonopah  railroad,  of  which  he  is  the  main 
owner.  Another  attempt  to  develop  a  deep 
mine  is  that  of  the  Goldfield  Belmont  com- 
pany, which  is  practically  owned  by  men  in 
the  Tonopah  Belmont  company.  This,  in 
turn,  is  closely  affiliated  with  the  Tonopah  & 
Goldfield  railroad,  which,  like  its  competitor, 
has  learned  that  a  district  that  ships  only  gold 
in  bricks,  even  if  shipments  are  occasionally 
in  ton  lots,  furnishes  but  little  freight.  The 
Tonopah  Belmont  people  have  made  a  con- 
spicuous and  deserved  success  at  Tonopah, 
as  has  Mr.  Clark  in  Montana  and  Arizona, 
and  the  serious  entrance  of  such  men  into  the 
Goldfield  district  means  much.  As  an  ex- 
ample of  the  contrast  between  present  and 
past  performance  there  it  is  worth  mention- 
ing that  both  the  Goldfield  Merger  and  the 
Goldfield  Belmont  properties  were  first  care- 
fully surveyed  by  a  competent  geologist, 
George  H.  Garrey,  of  Spurr  &  Co.,  and  plans 
for  development  were  formulated  after  that 
study.  These  and  the  Consolidated  are  not 
the  only  properties  at  Goldfield,  but  they  are 
the  ones  most  in  the  public  eye.  The  Flor- 
ence continues  regular  production,  ranking 
next  to  the  Consolidated,  and  a  number  of 
smaller  mines  are  shipping. 

Manhattan  is  another  of  the  Nevada  dis- 
tricts whose  early  history  was  marked  by  a 
blighting  boom,  but  which  now  bids  fair  to 
'  come  back  '  in  a  substantial  manner.  The 
War  Eagle  company  is  operating  the  mill 
built  for  the  Manhattan  (Dre  Reduction  & 
Refining  Co.,  on  the  basis  of  experimental 
work  done  by  F.  L.  Bosqui  and  J.  H.  G. 
Wolf.  While  the  mill  is  small,  consisting  of 
10  stamps,  it  operates  on  custom  ore  and  per- 
mits lessees  to  obtain  cash  returns.  One 
company  is  now  paying  dividends,  others  are 
being  re-organized,  litigation  is  being  settled, 
and  placer  mining  has  been  undertaken.  Al- 
together matters  are  distinctly  more  hopeful 
at  Manhattan  than  at  any  time  in  two  or 
three  years.  At  Wonder,  Nevada,  the  Ne- 
vada Wonder  M.  Co.  has  just  begun  crush- 
ing, and  nearby  the  Nevada  Hills  is  expected 
to  begin  in  a  few  days.  At  National  a  re- 
markable output  of  extremely  rich  ore  con- 


tinues to  attract  attention.  Dividends  have 
been  resumed  on  the  Comstock  and  there 
are  many  signs  of  a  more  prosperous  period 
for  Nevada  miners.  Incidentally  that  State 
has  now  one  of  the  strictest  laws  regarding 
organization  and  promotion  of  mining  com- 
panies of  any  American  State,  and  has  also 
recently  revised  its  law  regarding  mine  in- 
spection. The  new  statute  follows  closely 
the  draft  prepared  by  the  Mining  and  Metal- 
lurgical Society  of  America  and  the  only  criti- 
cism that  has  yet  been  made  is  that  it  is,  if 
anything,  too  full  and  strict.  That,  however, 
is  better  than  the  old  system  of  no  law. 

California  as  well  as  Nevada  is  feeling 
the  influence  of  a  returning  interest  in  gold 
mines.  Along  the  Mother  Lode  serious  studies 
of  the  possibility  of  cyanidation  are  being 
made.  The  standard  Mother  Lode  practice 
of  stamping,  amalgamation,  and  concentration 
on  vanners,  followed  by  treatment  in  canvas 
plants,  has  been  followed  so  long  that  belief 
in  its  perfection  has  become  ingrained.  Re- 
peated trials  of  new  processes  and  new  de- 
vices have  been  disappointing  and  mill-men 
along  the  Lode  have  settled  down  to  doing 
the  best  they  can  with  the  processes  in  use. 
It  is  generally  believed  that  the  tailing  losses 
are  but  25  to  30c.  per  ton  and  that  most  of 
this  loss  is  in  the  form  of  gold  locked  in  fine 
particles  of  pyrite.  The  sampling  of  tailing 
is  always  difficult  and  leads  to  many  discord- 
ant results  but  enough  is  now  known  to  make 
certain  that  tailing  losses  in  this  district  are 
several  times  greater  than  have  been  esti- 
mated. This,  with  the  improvement  made 
elsewhere  in  cyanidation  of  concentrate,  opens 
distinct  possibilities  of  increased  return  and 
working-scale  tests  may  be  expected. 

Attempts  made  by  San  Franciscans  to  buy 
the  Zeila  mine  at  Jackson  have  come  to 
naught  but  a  new  company  has  been  organ- 
ized, the  South  Jackson  G.  M.  Co.,  to  mine 
on  adjacent  ground.  Immediately  south  of 
the  Zeila  is  a  tract  that  has  long  lain  idle, 
presumably  because  it  was  held  under  agri- 
cultural title.  In  early  days  excellent  ore 
was  mined  to  a  depth  of  80  ft.  on  what  is 
considered  to  be  the  '  West  vein  '  of  the 
Mother  Lode.  A  shaft  is  now  being  sunk  on 
the  dip  to  intersect  this  vein  and  prospecting 
is  also  being  done  along  the  '  East  vein,' 
which  likewise  crosses  the  property.  The 
famous  old  Princeton  mine  is  also  to  be  re- 
opened. This  mine,  which  lies  within  the 
Mariposa  grant,  has  produced  over  $5,000,000 
and  has  been  worked  to  a  depth  of  several 
hundred  feet.     The  bottom  level  was  in  low- 


SEPTEMBER,    1911 


193 


grade  ore  and  some  time  since  was  aban- 
doned. Tlie  vein,  however,  is  large  and  well 
defined  and  since  horizontal  bands  of  low- 
grade  or  barren  rock  are  known  to  occur  in 
even  the  best  of  the  Mother  Lode  mines  the 
property  is  considered  worthy  of  further  test. 
As  Hennen  Jennings  and  W.  W.  Mein  are 
active  in  the  new  enterprise  it  goes  without 
saying  that  the  work  will  be  well  directed  and 
well  conducted. 

Shasta  county  mines  are  in  a  bad  way 
since  the  closing  of  the  copper  smelters  there. 
The  Mammoth  plant  of  the  United  States 
Smelting  Co.  is  the  only  one  now  in  opera- 
tion. It  is  a  striking  commentary  on  the 
situation  that  the  air  is  full  of  rumours  of  a 
joint  removal  on  the  part  of  the  companies 


ferred  to  Garfield,  Utah,  where  while  there  is 
no  trouble  from  smoke  damage  the  manage- 
ment desires  to  use  the  apparatus  to  minimize 
dust  losses.  The  process  is  also  being  ap- 
plied to  precipitation  of  dust  at  cement  plants. 
The  Riverside  Portland  Cement  Co.,  after 
several  months  experimental  work,  is  now 
equipping  its  plant  at  Coulton.  The  signifi- 
cant feature  of  this  work  is  that  the  precipi- 
tation must  be  conducted  at  much  higher 
temperatures  than  in  clearing  petroleum  of 
water,  settling  acid  fume,  or  handling  smelter- 
dust.  Mr.  Cottrell  is  now  in  general  charge 
of  western  metallurgical  investigations  for  the 
United  States  Bureau  of  Mines  and  just  at 
present  is  making  a  careful  study  of  the 
Washoe  smelter  at  Anaconda,  Montana. 


-^I|l^««»- 


«  B  f 


in[  w^  is    t^jt 


LA   BLANCA    MILL,   AT   PACHUCA. 


and  that  in 
M.  Co.  has 
considerable 
furnaces    at 


concerned  to  western  Nevada, 
the  meantime  the  Pacific  S.  & 
contracted  for  the  delivery  of  a 
tonnage  of  copper  ore  to  its 
Guaymas,  in  Mexico.  There  is  general  dis- 
appointment among  technical  men  at  the  fail- 
ure, in  part,  of  the  Cottrell  process  at  the 
Balaklala  smelter.  Tests  made  by  experts 
for  the  farmers  credit  it  with  an  average  per- 
formance of  72%,  though  individual  units  had 
been  brought  up  to  a  duty  of  90%  in  precipi- 
tation of  solid  particles.  The  simplicity  and 
low  cost  of  the  plant  are  strongly  in  its  favour 
and  among  those  who  have  watched  the  de- 
velopment of  the  process  there  is  a  general 
belief  that  ultimately  it  will  be  entirely  suc- 
cessful. Since  the  closing  of  the  Balaklala 
plants  the  experimental  work  has  been  trans- 


MEXICO. 
Tiro  General. — A  recent  transfer  of  im- 
portance was  that  of  the  Tiro  General  mines 
in  the  Charcos  district  of  San  Luis  Potosi, 
purchased  by  the  American  Smelting  c'v:  Re- 
fining Co.  at  a  price  of  1,600,000  pesos.  The 
purchase  included  the  Potosi  Central  railway, 
10  kilometres  long,  extending  from  the  mines 
to  Charcos  station,  on  the  National  Railways 
of  Mexico.  The  mines  have  been  owned  by 
the  Tiro  General  Mining  Co.,  composed  prin- 
cipally of  foreigners  living  at  Aguascalientes 
and  Mexico  City.  For  a  number  of  years 
they  have  been  shipping  steadily  to  the  Agua- 
scalientes  smelter  of  the  American  Smelting 
&  Refining  Co.  Shipments  have  ranged 
from  1500  to  4500  tons  of  ore  monthly.  The 
mines  are  aiitigiias,  extensively  developed, 


194 


THE    MINING    MAGAZINE 


with  a  record  of  having  produced  ore  worth 
many  miUions  during  the  last  century.  The 
valuable  constituents  of  the  ore  are  sulphides 
of  silver  and  copper,  with  lead,  zinc,  and  iron. 
A  few  years  ago  the  Tiro  General  Co.  tried 
dry  concentration,  but  the  treatment  was  not 
a  success  and  the  plant  was  closed. 

Oil. — The  Texas  Oil  Co.  has  purchased  80 
acres  of  land  on  the  Panuco  river,  at  Tam- 
pico,  preparatory  to  erecting  storage-tanks 
there,  purchasing  Mexican  crude  oil,  and  ex- 
porting to  the  United  States.  It  was  reported 
that  arrangements  had  been  made  to  handle 
the  surplus  crude  oil  of  the  Pearson  interests, 
but  a  few  days  ago  a  Pearson  representative 
in  Mexico  City  stated  that  the  Sherman  law 
of  the  United  States  might  interfere  with  the 
plan.  This  point  is  not  clear.  The  Nueva 
Era,  recognized  as  the  organ  of  Francisco  I. 
Madero,  recently  printed  a  telegram  from 
New  York  stating  that  Lord  Cowdray  had 
been  unsuccessful  in  attempts  to  dispose  of 
his  Mexican  oil  holdings,  because  foreign 
capitalists  feared  an  attack  by  the  Mexican 
Government  on  the  Pearson  concessions.  The 
East  Coast  Oil  Co.,  a  Southern  Pacific  con- 
cern, has  brought  in  a  gusher  of  from  10,000 
to  15,000  barrels  daily  in  the  Topila  field. 
Owing  to  the  ability  of  the  Doheny  interests 
to  furnish  large  supplies  of  oil  from  their  Juan 
Casiano  wells,  the  National  Railways  of 
Mexico  are  increasing  the  use  of  oil  as  loco- 
motive fuel.  The  Mexican  Petroleum  Co.  of 
California,  a  Doheny  company,  is  supplying 
oil  to  the  government  merger  system  under  a 
contract  made  with  the  Mexican  Central  Rail- 
way. 

Mexican  Light  &  Power. — The  annual 
report  of  this  Canadian  company  owning  the 
big  hydro-electric  installation  at  Necaxa,  State 
of  Puebla,  and  furnishing  current  to  Mexico 
City  and  the  mining  districts  of  El  Oro  and 
Pachuca,  shows  gross  earnings  of  6,990,398 
pesos,  and  net  earnings  of  5,021,625  pesos. 
The  operating  and  maintenance  expenses  were 
only  1,968,773  pesos,  as  against  2,991,207 
pesos  in  the  previous  year.  The  company 
reports  a  total  generating  capacity  of  129,920 
horse-power,  this  total  including  the  plants 
taken  over  in  Mexico  City  and  Pachuca  in 
addition  to  the  94,000  horse-power  possible  at 
Necaxa.  Contracts  have  been  let  for  the 
further  extension  of  the  system  of  canals  and 
tunnels  at  Necaxa,  which  will  result  in  divert- 
ing other  rivers  into  the  Necaxa  watershed, 
and  by  the  end  of  1912  the  generating  capacity 
at  Necaxa  will  be  much  greater. 

Lucky   Tiger. — A.    S.  Witherbee,   J.    J. 


Stein  and  A.  S.  Everest,  London  brokers, 
have  been  negotiating  for  an  option  to  buy 
645,000  shares  of  the  stock  of  the  Lucky  Tiger 
Combination  Gold  Mining  Co.,  owning  the 
Lucky  Tiger  gold  mine,  in  Sonora.  They  re- 
cently arrived  at  Kansas  City,  where  the 
majority  of  the  stock  is  held,  and  made  a  de- 
posit of  ^98,000  in  connection  with  the  de- 
sired option.  They  are  asking  for  6  months  on 
370,000  shares  at  $7  per  share,  and  9  months 
on  275,000  shares  at  $8  per  share.  A  total 
of  715,000  shares  of  stock  has  been  issued. 
The  par  value  is  $10  and  the  present  market 
value  $6  per  share.  It  is  reported  that  some 
of  the  large  shareholders  have  refused  to 
pledge  their  stock  for  6  and  9  months  at  the 
prices  offered,  and  the  deal  may  fail.  A  short 
time  ago  it  was  reported  that  English  interests 
were  in  a  position  to  obtain  control  of  the 
Lucky  Tiger,  by  the  purchase  of  some  stock 
and  a  combination  with  other  holders. 

CAMBORNE. 

Carn  Brea  &  Tincroft. — The  loss  on  the 
six  months  ended  June  30  was  ^1937  as  com- 
pared with  a  profit  of  £\Z  for  the  previous 
half-year.  The  yield  was  5 lb.  black  tin  per 
ton  less,  so  it  is  fortunate  that  the  price  of  the 
metal  was  higher,  the  average  price  obtained 
for  theconcentrate  being  ;^20  more  than  during 
the  previous  half-year.  The  total  receipts 
were  ;^1152  less,  and  the  expenditure  ^"798 
greater,  due  chiefly  to  the  increased  cost  of 
supplies.  I  give  below  the  chief  figures  for 
the  half-year  : 

Ore  crushed 38,253  tons 

Black  tin  sold 381  tons 

Average  yield  per  ton 22'29  lb. 

Average  value  per  ton 20s.  4d. 

Average  price  obtained  for 

black  tin   ^"102.  10s.  7d. 

Total  receipts  per  ton 21s.  5d, 

Total  cost  per  ton 22s.  5d. 

Development  footage 1637ft. 

From  this  it  will  be  seen  that  an  increase  in 
the  yield  of  1  lb.  per  ton  will  be  sufficient  to  turn 
the  corner;  judging  by  the  manager's  report, 
this  may  reasonably  be  expected.  Furthermore 
his  reforms  in  the  matter  of  purchasing  supplies 
in  the  open  market  and  in  the  methods  of 
mining  and  concentration  will  so  reduce  costs 
as  to  provide  a  substantial  margin  of  profit, 
always  supposing  that  the  price  of  tin  main- 
tains a  reasonably  high  level.  In  his  speech 
to  shareholders,  the  new  manager,  E.  S.  King, 
expatiated  on  the  necessity  of  properly  segre- 
gating mining  costs,  a  question  that  is  neg- 
lected at  most  Cornish  mines.     In  a  scattered 


SEPTEMBER,    1911 


195 


property  like  Carn  Brea  and  Tincroft,  it  is  of 
the  utmost  importance  that  departmental 
costs  should  be  accurately  known.  It  is 
gratifying  that  the  company  now  has  a  mana- 
ger who  appreciates  this  point,  and  I  hope 
his  influence  in  the  matter  will  be  felt  else- 
where. 

Condurrow. — The  progress  of  unwatering 
this  mine  is  slow.  The  water  is  now  being 
held  temporarily  at  the  272  fm.  level,  so  as 
to  enable  the  whole  of  the  underground  force 
to  be  concentrated  on  the  work  of  clearing 
the  260  and  272  fm.  levels.  The  ore  pre- 
viously left  behind  in  these  levels  has  proved 
to  be  richer  than  that  in  the  upper  levels,  and 
Captain  Tamblyn  believes  that  it  can  be 
treated  at  a  profit.     The  stamps  are  therefore 


sion  unquestionably  had  an  adverse  effect  on 
the  supply  of  capital  for  Cornish  mines,  par- 
ticularly because  the  work  was  being  done 
by  an  eminent  Cornish  group,  who  may  be 
supposed  to  understand  better  than  any  out- 
sider how  to  handle  local  mining  problems.  It 
is  much  to  be  hoped  that  this  fine  old  property 
will  once  more  be  reopened. 

Grenville. — This  mine  has  at  last  returned 
to  the  list  of  dividend  payers,  and  Captain 
Battens  is  to  be  heartily  congratulated  in 
wiping  out  a  debit  balance  of  over  ;^10,000 
during  his  year's  tenure  of  the  management. 
The  credit  balance  on  June  30  was  £199.  At 
the  meeting  of  shareholders,  the  board  de- 
clared a  dividend  of  4d.  per  share  10s.  paid, 
and  Id.  per  share  on  the  shares  2s.  6d.  paid. 


GUANAJUATO. 


being  prepared  for  action  once  more.  The 
company  has  had  no  possible  alternative 
policy,  for  the  capital  was  exhausted  at  the 
end  of  June,  and  something  had  to  be  done  to 
keep  the  mine  going,  while  the  board  con- 
sidered the  ways  and  means  of  raising  further 
funds.  There  is  some  expectation  that  the 
remaining  unissued  shares  will  be  placed 
within  a  short  time. 

Wheal  Vor.— This  historic  property  is 
still  '  marking  time,'  but  the  board  and  others 
are  anxious  to  have  another  try  at  unwatering. 
The  mine  is  historic,  not  only  as  one  of  Corn- 
wall's great  producers,  but  also  on  account  of 
the  fiasco  at  the  last  attempt  to  unwater  it 
three  years  ago.     The  failure  on  that  occa- 


This  will  absorb  about  {2250,  which  Thomas 
Negus,  the  chairman,  stated  had  been  earned 
since  the  closing  of  the  half-yearly  accounts. 
Many  people  think  it  would  have  been  wiser 
to  keep  the  profits  in  hand  as  reserve,  but  the 
general  conditions  and  prospects  are  so  satis- 
factory that  the  distribution  is  quite  legiti- 
mate. 

West  Kitty.— The  yield  at  this  St.  Agnes 
mine  continues  to  be  low,  but  development  is 
being  actively  prosecuted.  Both  the  Jericho 
and  Friendly  mills  are  working  at  full  capa- 
city, and  together  treat  600  tons  per  week. 
The  sale  of  concentrate  at  the  ticketings  aver- 
ages 14  tons  in  four  weeks,  so  the  recovery  is 
only  about  14  lb.  per  ton.     Much  of  the  ore 


196 


THE    MINING    MAGAZINE 


milled  at  Jericho  comes  from  the  Friendly 
section  of  the  mine,  and  is  nowadays  trans- 
ported by  steam  waggon  instead  of  the  old 
carts. 

Dolcoath. — The  world's  oldest  tin  mine 
returned  a  profit  of  ;^36,370  for  the  six  months 
ended  June  30  last,  during  which  time  853 
tons  of  black  tin  realized  just  over  ;^  100,000. 
The  yield  was  3'35  lb.  higher  as  compared 
with  the  previous  six  months,  but  the  amount 
of  ore  treated  was  4344  tons  less,  owing  to  the 
diminished  capacity  of  the  mill  during  the 
period  of  changing  over  from  the  old  Cornish 
stamps  to  the  air-cushion  or 'pneumatic' stamps. 
The  work  of  equipping  Williams  shaft  is  near- 
ing  completion,  and  it  is  expected  that  it  will 
be  in  operation  at  the  end  of  this  month.  It 
will  be  remembered  that  the  pumps  at  this  new 
shaft  are  to  be  driven  electrically,  and  Cornish 
mining  people  are  watching  the  change  with 
interest,  not  to  say  anxiety,  as  was  evidenced 
by  the  questions  asked  at  the  meeting  of  share- 
holders. The  following  figures  taken  from  the 
half-yearly  report  may  be  quoted  : 

Tons  milled 40,315 

Yield  per  ton  milled 47'38  lb. 

Average  price  of  black  tin ^117.  6s.  6d. 

Receipts  per  ton  milled 50s.  3d. 

Cost  per  ton  milled 32s.  2d. 

Profit  per  ton  milled 18s.  Id. 

The  above  working  cost  includes  nothing  for 
depreciation  or  income  tax,  which  together 
would  account  for  a  further  3s.  4d.  per  ton 
milled. 

Wheal  Coates. — This  mine  at  St.  Agnes 
has  been  unwatered  to  the  50  fm.  level  and  a 
thorough  examination  is  being  made  from 
adit  to  this  level.  It  is  nearly  thirty  years 
since  the  water  put  a  stop  to  operations  ;  at 
the  time  work  was  being  done  at  the  80  fm. 
level.  The  owners  did  not  have  means  to 
cope  with  the  inflow  of  water,  and  in  fact 
they  had  not  worked  the  mine  on  any  large 
scale.  At  the  present  time  the  examination 
is  said  to  be  giving  satisfactory  results  and 
the  owners  are  hoping  to  be  able  to  raise 
further  working  capital.  The  ore  is  reported 
to  be  clean,  as  is  the  case  with  most  mines  in 
the  St.  Agnes  district. 

East  Pool.  —  This  company  has  lost  its 
purser  and  secretary,  John  H.  Mayne,  who 
died  last  month  after  being  continuously  con- 
nected with  the  mine  for  over  forty  years. 
He  was  to  the  last  a  firm  believer  in  the 
cost-book  system,  and  held  that  it  was  as 
applicable  to  a  big  property  as  to  a  small 
prospect.  No  doubt  his  influence  was  strong 
in  preventing  any  change  to  limited  liability. 


NEW  YORK. 

Stock  quotations  started  a  decline  on 
August  2,  culminating  on  the  26th  in  new  low 
records  for  the  year.  Of  the  200  issues  traded 
on  the  Stock  Exchange  during  the  week  end- 
ing August  26,  no  fewer  than  123  shared  in 
this  unenviable  distinction.  This  occurred  in 
spite  of  remarkable  activity  ;  in  fact,  the 
number  of  transactions  on  August  10,  when 
1,033,630  shares  changed  hands,  was  the 
greatest  day's  total  for  the  current  year.  In 
the  short  interval  from  July  29  to  August  26, 
Amalgamated  dropped  9f  ;  A.  S.  &  R.,  lOi  ; 
Anaconda,  4k;  Chino,  3j  ;  Ray,  3i;  Tennessee 
Copper,  78  ;  U.S.  Steel  com.  9f  ;  Utah  Cop- 
per, 7.  Too  much  speculation  seems  to  be 
the  plainest  assignable  reason  for  this  big  drop 
in  market  prices.  Assuredly  nothing  relating 
to  the  intrinsic  value  or  earning  ability  of  the 
several  properties  can  be  deduced  from  the 
behaviour  of  the  market. 

The  copper  market  remains  in  a  condi- 
tion of  stable  equilibrium  ;  a  lower  price  is 
out  of  the  question  in  the  face  of  increasing 
consumption  and  diminishing  stocks  on  hand, 
and  a  higher  price  is  unlikely,  in  the  near 
future,  with  the  possibility  of  a  sudden  in- 
crease in  production  when  the  new  mines  of 
the  Southwest  shall  come  to  their  full  capacity. 
The  present  price  of  121  c.  per  lb.  is  likely  to 
be  closely  maintained  for  the  remainder  of  the 
year,  unless  aff"ected  by  speculation,  in  which 
case  the  net  result  will  undoubtedly  be  a  rise 
in  price.  London  speculators  appear  unani- 
mous in  the  belief  that  the  price  is  now  too 
low,  from  their  point  of  view,  and  they  are 
waiting  for  any  good  excuse  to  inaugurate  a 
rising  market.  A  peaceable  settlement  of  the 
Moroccan  difiiculty  is  mentioned  as  one  ex- 
cuse that  may  be  seized  upon  ;  another  is  the 
report  of  J.  R.  Finlay,  mentioned  in  another 
paragraph,  to  the  eff'ect  that  the  reserves  and 
the  future  productivity  of  the  Lake  Superior 
mines  are  not  as  great  as  they  have  been  sup- 
posed to  be,  coupled  with  the  statement  that, 
under  the  inexorable  operation  of  the  periodic 
law,  a  price  of  at  least  15  c.  per  pound  is  prac- 
tically certain  to  be  reached  shortly.  When 
the  force  of  Mr.  Finlay's  conclusions  has  been 
fully  considered  in  London,  it  may  possibly 
start  an  upward  movement.  Copper  produc- 
tion in  the  United  States  fails  to  respond  to 
the  efforts  at  curtailment ;  domestic  consumers 
still  hesitate  to  make  heavy  purchases  ;  these 
two  causes  would  combine  to  reduce  prices 
were  it  not  for  increasing  exports  to  Europe. 
Germany  in  particular  is  now  consuming  enor- 
mous quantities  of  copper,  and  stocks  on  hand 


SEPTEMBER,    1911 


197 


have  been  greatly  diminished.  In  the  United 
States  similarly  consumers  have  allowed  their 
stocks,  which  usually  constitute  two  or  three 
months  requirements,  to  dwindle  to  almost 
nothing,  and  they  are  now  supplying  their 
needs  from  day  to  day  ;  they  are,  in  fact,  able 
to  buy  spot  copper  cheaper  than  that  for  dis- 
tant delivery. 

Valuation  of  Michigan  mines,  which 
was  the  task  committed  to  J.  R.  Finlay,  of 
New  York,  to  be  completed  within  two  months 
of  his  notification,  was  accomplished  in  record 
time,  the  final  report  having  been  handed  to 
the  State  Board  of  Tax  Assessors  on  August 
21.  The  report  is  to  be  printed  and  will  be- 
come public  in  a  few  days.   From  proof-sheets 


total,  169,815,000.  The  iron  mines  are  simi- 
larly valued  as  follows:  Gogebic,  841,560,000; 
Iron,  $23,339,000;  Dickinson,  $11,508,000; 
Baraga,  $3,381,000  ;  Marquette,  $42,743,000  ; 
total,  $119,485,000.  The  coal  mines  of  the 
State  are  valued  at  $861,745.  After  due  con- 
sideration Mr.  Finlay  recommended  that  the 
salt,  gypsum,  cement,  and  clay  operations  be 
considered  as  manufacturing  rather  than  as 
mining  enterprises,  and,  therefore,  not  to  be 
included  in  the  present  valuation.  During 
the  last  five  years,  on  which  period  the  present 
investigation  was  based,  the  profitable  copper 
mines  of  Michigan  earned  $50,937,690  o\er 
expenditure,  but  these  earnings  are  considered 
abnormal,  owing  to  the  spectacular  prices  of 


OOLD    BAH    MINE    AND    MILL,   RHYOLITE,    NEVADA. 


in  Mr.  Finlay's  office  it  is  learned  that  the 
three  factors  considered  in  valuing  each  in- 
dividual mine  were  (l)  Price  received  for  pro- 
duct ;  (2)  Cost  of  production  ;  (3)  Life  of  mine. 
From  the  first  two  data,  the  net  profits  could 
be  computed,  and  this,  combined  with  the  third 
factor,  permitted  an  estimate  of  the  present 
value,  by  annuity  method.  In  the  present 
case,  a  sum  was  calculated  upon  which  the 
series  of  dividends  would  pay  5%  interest  and 
also  provide  each  year  a  sinking  fund  instal- 
ment which,  invested  each  year  at  4%,  and 
added  to  prior  instalments  similarly  invested 
and  re-invested  would  equal  the  sum  taken. 
This  sum  is  the  account  which  an  investor  can 
afford  to  pay  for  the  property. 

On  this  basis  Mr.  Finlay  values  the  cop- 
per mines  of  Michigan  as  follows  :  Keewee- 
naw  county,  $12,200,000;  Houghton  county, 
$57,315,000;  Ontonagon  county,  $300,000; 


copper  during  1906  and  1907.  Thus  in  1906 
the  net  earnings  were  $21,093,000,  whereas  in 
1910  they  were  only  $7,075,000.  During  the 
same  five  years,  the  iron  mines  of  the  State 
made  net  earnings  of  $57,55 1 ,202,  without  the 
benefit  of  abnormal  prices;  in  fact,  the  earn- 
ings of  1910  were  above  the  average  of  the 
five  years.  The  total  valuation  of  the  iron 
mines,  $1 19,485,000,  is  based  on  an  e.xpected 
annual  tonnage  of  10,922,000,  with  a  present 
total  estimate  reserve  of  1 95,04 1,80^>  tons. 
While  this  tonnage  is  all  that  can  now  be 
apportioned  among  the  various  properties  with 
any  degree  of  certainty,  the  several  districts 
are  expected  to  produce  ore  somewhat  as 
follows:  Marquette,  150,000,000;  Menominee, 
150,000,000  ;  Gogebic,  60,000,000  tons. 

Appraisal  of  Mines.— In  explaining  his 
method  of  appraisal,  Mr.  Finlay  takes  a  iirm 
stand  on  the  following  three  propositions,  per- 


198 


THE    MINING    MAGAZINE 


fectly  reasonable  to  a  thoughtful  engineer,  but 
often  overlooked  by  the  investing  public  :  (l) 
Unprofitable  mines  have  no  value,  and  were 
appraised  at  zero;  (2)  Stock-market  quotations 
are  not  reliable  as  a  means  of  determining  the 
value  of  a  mine,  and  in  the  present  investiga- 
tion were  totally  ignored  ;  (3)  Mining  plants 
have  no  value  apart  from  the  orebodies  that 
they  serve,  and  were  therefore  not  appraised. 
In  estimating  the  expected  net  proceeds  of  the 
Michigan  copper  mines,  Mr.  Finlay  confidently 
adopts  14c.  per  pound  as  a  conservative  esti- 
mate of  the  price  of  copper  for  the  next  10  years, 
but  expresses  his  personal  opinion  that  the  price 
will  exceed  15c.,  and  establishes  his  conclu- 
sions by  comparison  with  preceding  decades. 
The  forthcoming  production  from  the  new  por- 
phyry mines  of  the  West  should  cause  no  un- 
easiness, in  as  much  as  the  world's  consump- 
tion is  increasing  at  the  rate  of  100,000,000 
pounds  per  year,  which  will  counterbalance 
the  expected  mcrease  from  the  porphyry  mines 
in  about  three  years,  at  the  end  of  which  time 
conditions  will  again  be  favourable  for  high- 
priced  copper. 

SALT  LAKE  CITY. 

Copper.  —  Unless  there  is  a  sudden  and  un- 
expected change  in  the  scope  of  operations  at 
the  Utah  Copper,  a  heavy  increase  in  produc- 
tion may  be  anticipated  in  the  immediate 
future.  Mine  and  mill  are  ready  for  it.  At 
the  mine  18  steam-shovels  are  at  work  re- 
moving the  overburden  and  taking  out  ore, 
handling  a  total  of  about  50,000  tons  of  ore 
and  waste  daily.  The  report  for  the  quarter 
ending  June  30  shows  that  a  total  of  1,395,504 
cubic  yards  of  cap  was  handled  in  the  three 
months.  The  Bmgham  &  Garfield  railroad, 
built  to  haul  the  ore  from  the  mine  to  the  mill 
and  smelter,  is  practically  completed,  and  will 
be  in  full  operation  shortly,  when  all  the  roll- 
ing stock  has  arrived.  This  will  afford  ample 
facilities  for  hauling  all  the  ore  the  mine  can 
produce.  At  the  mill,  the  remodelling  of  the 
Arthur  or  old  Boston  Consolidated  plant  is 
progressing.  It  is  given  out  ofificially  that  the 
four  remodelled  sections  will  handle  as  much 
ore  as  the  entire  original  thirteen,  and  that  the 
two  plants,  Arthur  and  Magna,  will  soon  be 
in  shape  to  take  care  of  20,000  tons  of  ore 
daily.  An  interesting  announcement  in  the 
last  quarterly  report  opens  up  an  old  contro- 
versy. This  is  to  the  effect  that  the  Utah 
Copper  has  permanently  abandoned  the  use  of 
stamp-mills  for  the  crushing  of  porphyry  ore. 
When  the  Boston  Consolidated  mill  was  de- 
signed by  A.  J.  Bettles  (who  died  recently),  he 


caused  surprise  by  installing  stamp-mills  to 
handle  thelow-grade  copper-bearing  porphyry. 
The  great  problem  w^as  to  crush  fine  without 
sliming,  and  Mr.  Bettles'  experiments  had 
convinced  him  that  this  could  best  be  done  by 
the  stamps,  paradoxical  as  the  idea  seemed. 
The  original  Utah  Copper  plant  (now  the 
Magna)  was  being  built  about  the  same  time, 
and  many  comparisons  were  made  in  favour 
of  the  Bettles  method.  Mill-men  familiar  with 
both  plants  during  their  early  period  of  opera- 
tion declare  that  the  Boston  Consolidated  was 
making  a  much  better  saving  at  a  lower  cost 
with  the  same  or  a  lower  grade  of  ore.  This 
was  taken  as  one  of  the  grounds  for  criticism 
of  the  Utah  Copper  management.  When  the 
Utah  Copper  obtained  control  of  the  Boston 
Con.  and  merged  the  two  properties,  the  man- 
agement began  systematically  to  discredit  the 
use  of  stamps.  Various  reports  have  been 
circulated,  that  the  old  Boston  Con.  or  Arthur 
plant  was  not  giving  such  satisfactory  results 
.as  the  old  Utah  Copper  or  Magna  plant,  and 
that  it  was  necessary  to  remodel  it  along  the 
original  Utah  Copper  lines.  This  is  being 
done,  and  the  stamps  are  now  abandoned,  but 
despite  the  announcement  that  a  70%  is  being 
made,  there  are  many  competent  mill-men  who 
still  would  pin  their  faith  to  stamps  if  they 
had  the  problem  of  designing  a  plant  to  crush 
porphyry  ores  similar  to  those  at  Bingham. 

A  large  amount  of  development  work  is  in 
progress  at  the  Utah  Consolidated,  and  a  con- 
siderable tonnage  of  low-grade  copper  ore  is 
being  opened  up.  This  is  being  encountered 
between  the  1000  and  1100  levels. 

Nevada  Consolidated  showed  a  falling 
off  from  15,893,743  pounds  of  copper  for  the 
previous  quarter  ta  15,677,065  lb.  for  the 
quarter  ending  June  30.  The  decrease  is  ex- 
plained by  the  fact  that  it  was  necessary  to 
remove  a  large  amount  of  low-grade  material 
for  the  construction  of  tracks.  This  was  too 
valuable  to  waste,  and  so  it  was  all  sent  to 
the  mill,  bringing  the  average  for  the  quarter 
down  to  r59/o,  the  lowest  since  operations 
were  begun. 

Lead  -  silver  properties  all  through  this 
part  of  the  country  are  receiving  an  impetus 
through  the  competition  of  the  smelters  for 
this  class  of  ore.  The  new  lead  plant  of  the 
International  Smelting  &  Refining  Co.  at 
Tooele  will  soon  be  in  operation,  and  all  the 
smelting  companies  are  scouting  for  contracts. 
In  consequence,  inducements  are  being  of- 
fered for  ores  of  a  lower  grade  than  it  has 
been  possible  to  ship  heretofore.  This  makes 
available    several    millions    of    tons    of    ore 


SEPTEMBER,    1911 


199 


hitherto  left  in  the  mines  or  thrown  over  the 
dumps.  For  example,  the  May  Day  mine  at 
Tintic  recently  made  a  contract  enabling  it  to 
ship  ore  running  7%  lead,  7  oz.  silver  and  $3 
in  gold.  It  will  ship  ore  from  its  dumps  and 
slime  from  the  concentrator  that  have  accu- 
mulated for  a  period  of  years. 

Pioche,  Nevada . — After  long  negotiations, 
undertaken  by  various  sets  of  owners  over  a 
period  of  many  years,  a  consolidation  has 
been  finally  effected  of  some  of  the  leading 
mines  in  the  heart  of  this  district,  which  could 


which   over   $20,000,000   in 
has  been  extracted. 


silver-lead  ores 


MELBOURNE. 

New  South  Wales.— The  full  report  of 
the  Department  of  Mines  of  New  South  Wales 
for  1910  is  a  satisfactory  document  inasmuch 
as  it  discloses  that  minerals  to  the  value  of 
;/r8,736,000  were  won  as  against  ^7,636,000 
in  1909.  The  increase  is  partly  due  to  coal, 
the  output  being  8,173,000  tons  of  the  value 
of    ^3,009,000  ;    zinc,    468,627    tons,    value 


MINING    COPPER    OHE    AT    THE    NEVADA    CONSOLIDATED. 


not  profitably  be  worked  at  depth  without  co- 
operation. The  x\malgamated  Pioche  Mines 
&  Smelters  Corporation  has  acquired  the  pro- 
perties of  the  Nevada- Utah,  Ohio- Kentucky, 
and  Consolidated  Pioche.  As  far  back  as 
1876,  efforts  were  made  to  bring  some  of 
these  properties  together,  in  order  to  handle 
the  water  problem,  but  only  bitter  quarrels 
ensued,  resulting  in  the  practical  abandon- 
ment of  the  camp  for  many  years.  The  Ne- 
vada-Utah interests  are  now  in  control  of  the 
amalgamated  property.  A  $500,000  bond  is- 
sue has  been  financed  and  active  develop- 
ment work  at  depth  is  already  under  way. 
The  new  company  controls  about  1000  acres 
of  ground,  including  some  properties  from 
3—4 


^'1,290,000;  silver-lead  ore,  318,000  tons, 
value  ^'1,685,000.  The  high  price  of  tin  has 
prevented  any  shrinkage  in  the  value  of  the 
output  although  the  tonnage  was  less.  Cop- 
per, with  a  yield  of  12,890  tons  of  a  value  of 
;^486,000,  shows  an  increase.  Taken  gener- 
ally the  figures  fail  to  indicate  the  strengtli'of 
the  mineral  position  of  the  country.  What 
Australia  wants  is  extra  population;  in  fact, 
the  magnificent  coal  seams  of  New  South 
Wales  alone  should  yield  fuel  equal  in  value 
to  that  of  the  whole  of  the  present  mineral 
output  of  the  State.  The  yield  of  gold  is  de- 
clining and  will  fall  still  more  as  the  dredging 
industry  becomes  restricted.  Alluvial  tin  also 
is  being  exhausted  and  lodes  are  not  filling  the 


200 


THE    MINING    MAGAZINE 


gap,  but  there  are  a  number  of  low-grade 
copper  formations,  which  if  labour  were  less 
costly  would  pay  to  work  ;  as  it  is,  however, 
they  have  to  lie  idle.  This  is  also  the  position 
with  a  large  number  of  small  lead  and  zinc 
properties.  Still  more  does  the  remark  apply 
to  the  large  bodies  of  iron  ore  in  different 
parts  of  the  State.  The  labour  party  does  not 
want  population  because  its  leaders  fail  to 
recognize  that  large  population  means  large 
employment. 

Broken  Hill.  —  The  mining  industry  at 
Broken  Hill  is  m  a  flourishing  condition.  A 
splendid  discovery  hasbeenmade  at  the  British 
mine  which  property  was  floated  in  London 
within  two  years  of  the  discovery  of  the  Bar- 
rier range  in  1886.  The  British  blocks  com- 
prise the  two  northern  claims  owned  by  the 
Broken  Hill  Proprietary  Co.,  and  were  taken 
to  London  by  William  Knox,  the  belief  being 
that  the  orebodies  in  them  would  make  the 
flotation  a  huge  success.  Unfortunately  it 
was  found  that  the  big  shoots  of  ore  petered 
out  at  a  shallow  depth,  and  although  there 
have  been  in-and-out  periods  of  prosperity, 
owing  to  finds  here  and  there  on  the  two  big 
claims,  no  discovery  of  importance  has  been 
made  since  the  early  days.  Now,  however, 
off  Thompson's  shaft  just  in  the  middle  of  the 
property,  the  presence  of  a  new  shoot  of  ore 
has  been  disclosed.  At  800  ft.  a  stope  1 10  ft. 
wide  has  been  developed.  At  first  this  was 
thought  to  be  a  portion  of  the  eastern  vein,  a 
somewhat  narrow  shoot  of  ore  that  persists 
the  whole  length  of  the  property,  in  some 
places  as  much  as  40  ft.  m  width,  and  at  others 
only  10  ft.  To  prove  the  extent  of  the  shoot 
boring  was  started  in  the  600  ft.  level  above, 
with  the  result  that  a  length  of  over  400  ft.  of 
ore  ranging  up  to  154  ft.  in  width  and  of  high 
value  was  proved.  Drilling  is  now  being  done 
at  the  500  ft.  level  and  ore  has  been  found, 
while  at  900  ft.  after  opening  the  plat  and 
cross-cutting  a  few  feet  ore  has  been  met.  No 
work  has  been  done  overhead  in  this  shoot 
from  the  800  ft.  level,  so  that  there  is  practi- 
cally a  new  mine.  For  25  years  different 
managements  have  been  in  search  of  a  find 
of  this  kind,  but  it  was  only  when  the  last 
corner  left  untouched  was  entered  that  the 
discovery  occurred.  The  greatest  praise  is 
due  to  the  manager,  W.  H.  Woodhead,  for 
his  belief  in  the  property  and  his  determina- 
tion to  test  this  part  of  the  ground  before 
finally  saying  that  he  could  see  the  end  of  the 
ore  reserves. 

At  the  North  Broken  Hill   mine  ore  has 
been   struck  at  the   No.    12  level  (1250  ft.). 


Judging  from  the  extent  of  the  orebody  in  the 
adjoining  Junction  North  mine,  this  level,  if 
nothing  untoward  happens,  should  be  highly 
productive.  A  still  more  interesting  develop- 
ment is  the  opening  up  at  the  Central  mine  of 
the  Sulphide  Corporation,  at  the  south  end  of 
the  range,  of  a  fine  body  of  ore  at  the  No.  12 
level.  This  orebody  is  pitching  into  the  South 
Broken  Hill  mine,  the  value  of  which  is  en- 
hanced accordingly. 

The  zinc  industry  is  doing  exceedingly  well, 
owing  to  the  success  of  the  flotation  processes. 
They  now  are  treating  slime  as  well  as  the 
ordinary  residues.  Indeed,  the  Junction  North 
Co.  has  just  purchased  275,000  tons  of  slime 
at  prices  ranging  up  to  8s.  6d.  per  ton.  Two 
years  ago  the  idea  of  buying  this  material  for 
treatment  at  all  would  have  been  scouted  un- 
less by  the  method  of  sintering  for  smelting 
in  the  lead  furnaces.  That,  of  course,  would 
mean  a  loss  of  the  zinc  content.  Now  this 
treatment  by  flotation,  and  especially  by  the 
Minerals  Separation  process,  means  that  the 
zinc  is  saved  and  a  considerable  percentage  of 
the  lead.  The  Broken  Hill  Proprietary  Co. 
is  now  treating  slime  by  what  is  virtually  the 
Potter  process.  The  ten  zinc  furnaces  will 
be  at  work  shortly,  as  all  difficulty  with  re- 
spect to  clays  has  been  overcome.  The  labour 
available  is  being  put  on  the  bonus  system 
and  the  expert  brought  by  the  company  from 
Europe  to  instruct  the  staff  is  highly  gratified 
with  the  progress  made  by  the  workers,  their 
intelligent  aptitude  being  striking.  Som.e  of 
the  mining  men  at  Broken  Hill  question  the 
wisdom  of  the  company  spending  ^100,000  in 
the  erection  of  the  zinc  works.  The  officials 
however  are  satisfied  that  they  will  be  able  to 
show  highly  profitable  results.  There  is  a 
local  market  for  spelter,  and  the  East  can  be 
looked  to  for  a  market  for  the  surplus.  The 
Iron  Knob  iron  ore  deposit  may  be  exploited 
and  galvanized  iron  made.  Though  nothing 
definite  can  be  learned,  the  impression  is  that 
thedirectors  have  alarge  industrial  programme 
ahead.  Hence  G.  D.  Delprat's  visit  to  Europe. 
If  so  the  company  is  not  the  dying  giant  that 
many  people  would  describe  it  as  being. 

Export  Duties. — In  New  South  Wales 
the  dominant  labour  party  is  being  asked  to 
take  steps  to  induce  the  Federal  parliament  to 
impose  an  export  duty  on  lead  and  zinc  con- 
centrates. This  matter  has  been  alluded  to 
before  in  these  columns,  but  now  those  moving 
have  come  more  into  the  open.  The  large 
works  erected  at  Port  Kembla  partly  by  the 
Mount  Morgan  interests  are  known  to  be  in- 
terested in  this  movement. 


SEPTEMBER,    1911 


201 


METAL  MARKETS 

COPPER. 

Average  prices  of  cash  standard  copper: 
August  1911.       July  1911.  August  1910. 

£bb.  7s.  6d.     ^56.  15s.  6d.         £Sb.  17s.  5d. 

In  spite  of  political  nervousness  in  Europe 
and  labour  disturbances,  copper  has  shown  a 
noteworthy  steadiness  of  price.  While  the 
prices  of  securities  and  of  the  leading  com- 
modities have  slumped,  metals  generally  and 
copper  in  particular  have  been  little  affected, 
although  the  volume  of  business  has  natur- 
ally decreased.  During  the  greater  part  of 
the  month  England  entirely  ceased  buying 
and  continental  purchases  although  fostered 
by  concessions  from  the  American  producers 
have  only  been  moderate.  Speculators  re- 
main shy.  The  statistical  position  is  felt  to 
be  not  altogether  encouraging.  In  Europe 
there  was  the  first  increase  for  eighteen  months 
in  the  visible  supplies,  while  the  decline  in 
American  stocks  for  July  was  due  entirely 
to  a  decrease  in  refinery  output  brought  about 
by  the  abnormal  heat.  There  is  still  no  im- 
provement in  the  domestic  consumption  in 
America  and  the  expectations  of  an  autumn 
revival  in  trade  show  no  signs  of  being  re- 
alized. The  situation  however  gives  no  en- 
couragement to  bears. 

TIN. 

Average  prices  of  cash  tin  : 

August  1911.        July  1911.        August  1910. 

^190.  9s.  7d.  ^193.  2s.  Od.  £\S5.  8s.  2d. 
Tin  has  been  quieter  than  has  been  the  case 
for  some  time  past.  The  syndicate  seems  still 
to  have  control,  but  its  operations  are  less 
aggressive  than  of  late,  and  the  real  position 
is  obscure.  Business  with  America  was  sus- 
pended for  a  time  as  the  strikes  made  tran- 
shipment in  London  impossible,  and  in  con- 
sequence an  artificial  advance  was  established 
in  America  until  timely  arrivals  from  the 
Straits  relieved  the  situation.  Speculation 
has  almost  ceased.  The  tinplate  industry  is 
still  fully  occupied  and  is  absorbing  a  large 
tonnage  of  metal.  The  East  has  been  a 
moderate  seller  during  the  whole  of  the  month, 
and  has  obtained  good  prices  from  America. 
The  fluctuations  in  the  London  market,  though 
still  considerable,  ranging  between  £\^^  and 
;^187.  10s.  for  cash,  are  less  violent  than  re- 
cently. At  one  time  there  was  rather  a  flurry 
for  spot  metal  to  fulfil  contracts  where  the 
strike  made  it  impossible  to  land  tin  from  im- 
port steamers,  but  the  offerings  became  liberal 
and  the  advance  was  not  maintained. 


SPELTER. 

Average  prices  of  good  ordinary  spelter : 
August  1911.         July  1911.         August  1910. 
;^26.  lis.  Id.     £2\.  13s.  lOd.     ^22.  14s.  Od. 

The  strength  of  this  market,  to  which  we 
have  drawn  attention  during  the  past  few 
months,  culminated  in  a  sensational  rise  of 
£2  per  ton  during  August.  Supplies  have 
been  so  inadequate  that  consumers  were  will- 
ing to  pay  almost  any  price.  Galvanizers 
have  advanced  prices  of  sheets  and  the  de- 
mand may  be  somewhat  checked  thereby.  So 
great  a  rise  in  so  short  a  period  should  make 
buyers  pause  and  ask  themselves  if  the  ad- 
vance is  not  overdone.  It  is  quite  possible 
that  in  spite  of  the  demand  and  the  limitation 
of  production,  £21 .  10s.  may  mark  the  crest 
of  the  wave. 

LEAD. 

Average  prices  of  soft  foreign  lead  : 
August  1911.         July  1911.         August  1910. 
;^14.  Is.  4d.     ^13.  10s.  lid.      ^12.  10s.  9d. 

The  stronger  tendency  in  this  market  is 
gradually  being  realized  by  the  trade.  The 
consumption  is  fully  up  to  the  highest  records 
but  production  has  undergone  a  considerable 
falling  off.  The  Mexican  trouble,  strikes  in 
Spain,  and  the  scarcity  in  shipping  tonnage 
make  it  difficult  to  bring  forward  sufficient 
supplies  for  the  requirements  of  the  London 
market.  As  much  as  £\\.  lis.  3d.  for  foreign 
has  been  paid  for  early  delivery  ex  ship  and 
consumers  are  poorly  provided  beyond  Sep- 
tember. At  the  London  desilverizing  works, 
a  strike  continued  during  the  whole  month  and 
has  further  curtailed  supplies.  Continental 
demand  is  large  as  usual  before  the  close  of 
Baltic  navigation.  It  seems  inevitable  that 
the  advance  must  continue  and  a  considerably 
higher  level  of  prices  must  be  attained. 

OTHER  METALS  AND  MINERALS. 

Prices  quoted  on  September  9  : 

Silver.— 24jd.  per  oz. 

Platinum.— 178s.  6d.  per  oz. 

Bismuth.— 7s.  6d.  per  lb. 

Aluminium.— ;^59  per  ton. 

Nickel.— ;^170  per  ton. 

Cobalt.- -9s.  9d.  per  lb. 

Antimony. — £21  per  ton. 

Quicksilver.— iTS.  12s.  6d.  per  flask 

Manganese  Ore.— 8d.to9|d.  per  unit  (1%). 

Iron  OrI'.— Cumberland  hematite  19s.  6d. 
per  ton  at  mine.    Spanish  19s.  delivered. 

Pig  Iron.— Cleveland  47s.  per  ton.  He- 
matite 62s.  per  ton. 

Wolfram  Ore— 31s.  per  unit  (1%;. 


DEEP  MINING  ON  THE  RAND 


By  ROWLAND   GASCOYNE. 


THERE  seems  every  prospect  that  the 
Rand  goldfield  will  be  exploited  to  a 
greater  depth  than  any  other  mining  dis- 
trict in  the  world.  Already  several  of  the 
Rand  mines  rank  among  the  deepest  gold 
mines  of  the  world,  and  no  apparent  definite 
limit  to  mining  appears  as  yet  within  sight. 
There  are  several  reasons  why  the  Rand  may 
be  expected  to  establish  a  world's  record  in 
deep  mining,  such  as  low  increase  of  tempera- 
ture with  depth,  excellent  underground  condi- 
tions, and  unusual  facil ities  for  obtaining  cheap 
electrical  power. 

It  is  an  important  fact  that  the  underground 
temperature  on  the  Rand  increases  with  depth 
slower  than  in  any  other  goldfield,  and  much 
slower  than  in  any  known  coalfield.     About 
two  years  ago  Mr.  Lionel  Phillips,  at  a  Cham- 
ber of  Mines  meeting,  gave  some  particulars 
of  observations  taken  at  several  of  the  deepest 
mines.     These  showed  that  up  to  a  depth  of 
4420  ft.  the  temperature  increased  on  the  aver- 
age 1°F  for  every  255  ft.  of  depth.      There 
were  some  anomalies,  it  is  true,  the  highest 
temperature    recorded    being    84j°F    in    the 
Brakpan  mine  at  3640  ft.  from  the  surface, 
while  at  the  depth  of  4420  ft.  in  the  Jupiter 
mine  the  temperature  was    only  81°F,    but 
judging  from  the  average  increase  shown  by 
a  large  number  of  observations,  that  at  the 
Jupiter  was  more  nearly  correct.     The  under- 
ground temperature  conditions  on  the  Rand 
seem  to  be  approached  only  by  some  mines  in 
the  United  States,  where  mining  operations 
are  conducted  at  about  a  thousand  feet  deeper. 
Generally  speaking  the  rock  temperature  in- 
creases in  coal  mines  at  least  1°F  for  every 
additional  60  ft.  in  depth.  To  show  how  Rand 
conditions  are  conducive  to  deep  mining,  it 
may  be  pointed  out  that  a  depth  of  4500  ft. 
has  been  reached  without  any  attempt  at  arti- 
ficial ventilation.     This  must  be  considered 
unique  in  the  annals  of  deep  mining.  At  the 
present   time,   however,    for  health  consider- 
ations alone,  many  of  the  outcrop  as  well  as 
the  deep -level   mines  are  being  fitted  with 
ventilating  fans. 

Another  valuable  asset  possessed  by  the 
Rand  goldfield  when  deep  mining  possibilities 
are  considered  is  the  unusually  favourable 
country  rock  prevailing  over  the  greater  part 
of  the  district,  especially  the  excellent  quart- 


zite  lode-walls.     In  the  Far  East   Rand,  the 
footwall,  it  is  true,  is  formed  of  slate,  a   con- 
dition  less  conducive  to  deep    mining    than 
quartzite  owing  to  its  inability  to  carry  weight- 
strains  to  the  same  extent  as  quartzite.  Some 
years  ago  the  Johannesburg  municipality  made 
several  tests,  in  order  to  arrive  at  the  strength 
of  the  quartzites  on  the  Central  Rand,  and, 
generally  speaking,  the  experiments  went  to 
show  that  the  weight  they  would  carry  with- 
out fracturing  bore  a  close  relation  to  their 
specific  gravity.     Out  of  a  dozen  quartzites 
tested  it  was  estimated  that  the  average  depth 
at  which  the  weight  of  the  superincumbent 
strata  would  approach  the  limit  of  capability 
to  resist  fracture  would  be  in  the  neighbour- 
.  hood  of  3690  ft.,  while  some  of  the  hardest 
quartzites  would  not  fracture,  under  similar  con- 
ditions, until  a  depth  of  5567  ft.  was  reached. 
Naturally  at  shallower  depths  than  these,  in 
actual    mining   operations,  pillars    would  be 
liable    to    fracture,    owing   to    the    increased 
weight  thrown  on  them  by  mining  operations, 
and  instances  are  known  where  they  have  thus 
fractured,  at  less  depth   than   those    already 
mentioned,  owing  no  doubt  to  the  pillars  hav- 
ing to  carry  the  weight  of  the  superincumbent 
strata  over  the  adjacent  exhausted  areas.     It 
must  be  noted  that  these  remarks  are  based 
upon  the  pressure  necessary  to  fracture  quart- 
zite, and  it  may  be  that  the  beds  of  banket 
vary  but  little  in  their  capability  to  withstand 
pressure  as  compared  with  quartzite,  and  have 
therefore  been  considered  accordingly.    Judg- 
ing however  from  the  action  of  shale  when 
subjected,    along   with    quartzite,    to    lateral 
pressure,  of  which  instances  may  be  seen  in 
the  Lower  Witwatersrand  division,  the  foot- 
wall  shale  in  the  Far  East  Rand  must  be  re- 
garded as  an  element  of  weakness  when  deep 
mining  possibilities  are  considered,   because 
they  will  fracture  and  yield  at  a  much  lower 
pressure  than  that  to  which  an  ordinary  quart- 
zite will  succumb. 

Quartzite  from  the  Robinson  mine  at  a 
depth  of  3500  ft.  showed  fracture  at  a  pres- 
sure of  6804  lb.  per  sq.  in.,  and  crushed  at  a 
pressure  of  9029  lb.  per  sq.  in.  The  danger 
zone  is  reached  when  fractures  begin  to  show, 
so  that  7000  lb.  pressure  per  sq.  in.  would 
probably  be  somewhat  near  the  point  at  which 
the  quartzite  of  the  present  deep  mines  would 

102 


SEPTEMBER,    1911 


203 


CINDERELL 


A    DEEP    MINE,  4500  FT.    DEEP. 


204 


THE    MINING    MAGAZINE 


fracture.  With  a  pressure  of  10,0001b.  per 
sq.  in.  they  might  be  expected  to  crush.  Now 
a  column  of  quartzite  one  square  inch  in  area 
gives  a  weight  of  1222  lb.  for  every  foot  in 
depth,  and  this  fracturing  pressure  of  7000  lb. 
would  therefore  be  reached  at  a  depth  of  5728 
ft.  The  crushing  stage  would  probably  be 
reached  in  the  neighbourhood  of  8000  ft.,  that 
is,  provided  the  whole  of  the  weight  of  the  hang- 
ing wall  was  moving,  so  that  the  maximum  pres- 
sure was  exercised  by  the  hanging  wall.  In 
coal  mining  a  similar  condition  of  affairs  would 
be  produced  at  a  depth  of  2000  feet  only. 

Little,  however,  seems  to  be  known  about 
the  action  of  the  Rand  hanging  walls.  In  coal 
mining,  where  the   roof   consists    largely   of 
shale,  and  the  method  of  working  is  long-wall, 
the  total  extraction  of  the  seam  soon  shows  its 
effect  at  the  surface.     Whereas  on  the  Rand, 
the  hanging  wall  consists  of  hard  metamor- 
phosed   sandstone,    much    less    flexible   than 
shale  or  slate.     This  has  a  tendency  to  move 
in  large  blocks,  and  a  much  longer  period  will 
probably  expire  before  the  effects  of  mining 
are  experienced  at  the  surface  than  would  be 
the  case  with  more  flexible  roofs.     In  time, 
however,  the  result  of  the  total  extraction  of 
the  banket  lodes  on  the  Rand  must  invariably 
reach  the  surface,  but  the  greater  time  re- 
quired to  set  the  hanging  on  the  move  is  un- 
doubtedly a  great  advantage  to  mining  opera- 
tions.    If  underground  operations  are  to  be 
conducted  so  as  to  render  the  movement  of 
the  hanging  wall  totally  impossible,  as  many 
engaged  in  mining  in  this  locality  believe  pos- 
sible, then  at  a  depth  of  2000  ft.,  nearly  a  third 
of  the  lode  would  have  to  be  left  in  the  shape 
of  pillars,  to  produce  absolute  security  from 
any  fracture  or  movement  in  the  hanging  wall. 
At  a  depth  of  3000  ft.,  it  would  be  necessary 
to  leave  fully  one-half  in  the  shape  of  pillars, 
to  produce  the  same  results,  while  at  a  depth 
of  6000  ft.  from  the  surface  it  will  become 
impossible  to  mine  without  running  the  risk 
of  the  hanging  wall  ultimately  moving,  and 
fracturing  any  pillars  that  may  be  left  behind. 
From  these  estimates  it   would  appear  that 
mining  operations  can  be  conducted  on  the 
Rand  at  least  three  times  deeper,  without  set- 
ting up  the  same  conditions,  than  in  coal  min- 
ing,  and  as  the  limit  to  payable   mining  at 
collieries  is  fixed  at  4000  ft.,  the  equivalent 
maximum  depth  on  the  Rand,  other  conditions 
being  equal,  would  be  in  the  neighbourhood 
of  1 2,000  ft.    But  then  again  the  economic  con- 
ditions of  gold  mining  are  quite  different  from 
those  of  coal  mining,  and  are  moreover  alto- 
gether in  favour  of  the  former.   For  instance, 


in  the  case  of  coal  mining,  it  is  estimated  that 
at  a  depth  of  4000  ft.  not  only  would  the  tem- 
perature be  too  high,  but  the  pressure  of  the 
superincumbent  strata  would  be  so  severe,  as 
to  reduce  the  proportion  of  sound  coal  pro- 
duced to  such  an  extent  as  to  make  mining 
well  nigh  unprofitable.  In  gold  mining  this 
reduction  of  the  output  to  small  dimensions 
has  less  terrors  and,  on  this  account,  it  would 
seem  impossible  to  place  any  limit  to  deep 
mining  on  the  Rand,  by  reason  of  the  effects 
of  the  pressure  of  the  superincumbent  strata. 
The  difficulties  caused  thereby  can  be  dis- 
missed from  further  consideration,  provided 
however  that  the  ore  is  worked  on  a  system 
approaching  that  of  long-wall,  and  sand-fill- 
ing on  an  extensive  scale  is  adopted. 

The  question  of  underground  temperature 
as  an  obstacle  to  deep  mining  on  the  Rand 
has  been  already  discussed,  and  it  has  been 
shown  that  the  increment  with  depth  is  prob- 
ably lower  than  in  any  known  mining  region. 
If  the  result  of  the  latest  observations  be  taken 
into  consideration,  and  due  allowance  be  made 
for  the  cooling  effect  of  ventilation,  the  same 
temperature  will  not  be  reached  on  the  Rand 
until  a  depth  of  at  least  12,000  ft.  from  the 
surface  has  been  attained.  Again,  in  its 
coloured  labour  the  Rand  possesses  an  advan- 
tage by  no  means  negligible,  for  these  native 
workers  will  be  able  to  maintain  their  effi- 
ciency, such  as  it  is,  in  a  temperature  much 
higher  than  that  to  which  European  or  white 
labour  of  any  description  could  submit. 

An  impression  prevailed  not  long  ago  that 
the  most  formidable  obstacle  to  deep  mining 
on  the  Rand  was  that  of  deep  winding.  At 
that  time  the  application  of  electricity  to  min- 
ing operations  was  in  its  infancy,  and  it  was 
not  foreseen  that  the  Rand,  with  its  cheap 
coal  and  sufficient  water,  would  offer  an  ex- 
cellent field  for  the  production  of  electrical 
power  at  such  a  low  cost  as  a  farthing  per 
unit.  For  convenience,  efficiency,  and  cheap- 
ness, the  Rand  therefore  possesses  just  the 
agent  to  solve  the  deep  winding  problem.  It 
has  been  decided  that  the  best  plan  is  to  adopt 
stage-winding.  The  limit  to  deep  winding 
from  an  economic  standpoint  being  fixed  at 
3000  ft.,  it  has  been  decided  to  adopt  this 
depth  as  the  limit  for  each  stage.  This  pro- 
posal has  been  adopted  by  all  the  large  mines 
with  extensive  areas  on  the  dip,  and  main 
levels  are  being  driven  throughout  the  whole 
length  of  the  properties,  which  are  intended  to 
be  fitted  with  modern  haulage  arrangements 
so  as  to  act  as  feeders  to  the  shafts.  The 
shafts  are  being  fitted  so  as  to  hoist  from 


SEPTEMBER,    1911 


205 


4000  tons  to  6000  tons  during  the  shift  of  10 
hours.  This  then  is  the  proposed  solution  to 
what  appeared  the  most  difficult  problem  in 
connection  with  deep  mining  on  the  Rand,  but 
it  is  evident  that  without  such  a  handy  and 
cheap  power  as  that  of  electricity,  any  other 
solution  on  similar  lines  would  have  been 
clumsy  and  costly  to  effect. 

With  a  low  temperature -gradient,  sound 
rock-walls,  and  cheap  electrical  power,  there 
is  therefore  every  prospect  of  deep  mining 
being  unhindered.  The  ultimate  depth,  how- 
ever, to  which  mining  operations  on  the  Rand 


to  regard  them  as  always  liable  to  change,  in- 
asmuch as  low-grade  areas  will  continue  to 
alternate  in  depth  with  richer  areas,  just  as 
they  have  done  during  the  last  fifteen  years. 
Actual  past  yields  constitute  no  reliable  guide, 
as  they  have  always  been  subject  to  manipu- 
lation, to  obtain  the  best  results  either  in  the 
shape  of  high  profit  or  low  working  cost.  On 
the  whole  there  seems  no  reason  to  expect 
that  the  average  assay-value  will  drop  below 
5  dwt.  per  ton  for  many  years,  and  at  this 
yield  the  Rand  mines  ought  to  be  worked  at 
a  profit,  since  the  average  working  cost  will 


RAND    COLLIERIES    GOLD   MINE,  3000  FT.    DEEP. 


will  be  carried  is  difficult  to  fix,  because  there 
are  other  important  factors  to  be  taken  into 
consideration  in  addition  to  those  already 
mentioned.  It  is  clear  that  deep  mining  will 
only  be  carried  on  so  long  as  it  is  profitable, 
and  as  this  depends  upon  the  grade  of  the  ore, 
which  to  a  large  extent  cannot  be  ascertained 
until  actually  exposed,  it  becomes  impossible 
to  fix  a  definite  limit.  An  impression  seems 
to  be  abroad  that  the  lodes  of  the  Rand  be- 
come impoverished  in  depth  ;  undoubtedly  in 
some  cases  they  do,  but  in  others  they  im- 
prove, and  perhaps  the  most  correct  view  is 


decline  rather  than  advance  with  increasing 
depth.  The  conclusion  then  is  that  tempera- 
ture, rock-pressure,  and  deep-winding  prob- 
lems offer  little  difficulty  to  mining  on  the 
Rand  down  to  a  depth  often  or  twelve  thousand 
feet,  and  the  only  real  difficulty  is  that  of  ore- 
value,  for  which  there  is  of  course  no  artificial 
solution.  Should  the  ore  maintain  its  present 
average  value  and  working  costs  decline,  as 
seems  probable,  he  would  be  a  bold  engineer 
who  would  venture  to  fix  a  depth  beyond  which 
it  will  be  impossible  to  carry  on  mining  opera- 
tions on  the  Rand. 


206 


THE    MINING    MAGAZINE 


Cyanidation  of  Silver  Ore  at  Cobalt, 

Until  recently  the  silver-bearing  ores  and 
concentrates  of  Cobalt,  Ontario,  have  been 
sold  to  smelters,  and  we  have  given  particulars 
of  the  method  and  terms  of  sale  of  the  various 
qualities.  During  the  last  year  or  two  several 
of  the  managers  have  turned  their  attention  to 
the  applicability  of  the  cyanide  process  as  an 
alternative  method  of  beneficiating  the  ores. 
We  are  able  by  the  courtesy  of  Mr.  A.  G. 
Kirby  to  give  herewith  the  flow-sheet  of  the 
cyanide  plant  designed  and  erected  by  him  at 
the  Nova  Scotia  mine.  This  mine  was  not 
one  of  the  surface  bonanzas,  and  it  was  only 
after  much  prospecting  and  development  that 
profitable  lodes  were  disclosed.  Some  of  the 
ore  is  found  in  small  veins  of  calcite  that  carry 
metallic  silver,  smaltite,niccolite,  and  sulphides 
of  bismuth,  but  most  of  it  consists  of  thin 
sheets  of  silver  distributed  through  thecountry- 
rock,  diabase.  The  rock  is  extremely  hard  and 
tough.  In  mining,  the  lumps  of  silver  are 
picked  out  in  the  stopes  as  the  ore  is  broken, 
so  as  to  avoid  trouble  in  the  crushers.  The 
ore  is  first  reduced  to  2  in.  size  in  a  Hadfield 
gyratory  machine  (2)  and  then  elevated  to  a 
trommel  (7  7)  with  Ih  in.  holes,  the  oversize 
going  to  rolls  (7J).  An  elaborate  system  of 
sampling  is  provided,  as  shown  in  the  illustra- 
tion. The  ore  is  then  sent  to  20  stamps  of 
15001b.  each  (27)  dropping96times  per  minute, 
with  screens  of  16  mesh.  Cyanide  solution  is 
used  in  the  battery.  The  pulp  is  delivered  un- 
sized to  four  No,  2  Deister  tables  {22)  for  the 
removal  of  the  '  metallics  '  and  rich  sulphides. 
No  effort  is  made  to  make  a  close  saving  by 
concentration,  the  object  being  to  remove  such 
material  as  requires  a  relatively  long  time  of 
contact  with  cyanide  solution,  and  thus  to  keep 
the  size  of  metallic  silver  particles  within  the 
time-range  of  the  continuous  agitation,  the 
average  cycle  of  which  is  72  hours.  The  con- 
centrate is  consequently  rich,  running  from 
2500  to  5000  oz.  per  ton,  the  ratio  of  concentra- 
tion being  from  80  or  100  to  one.  It  is  charged 
into  a  5  ft.  amalgamating  pan  (50)  in  1500  lb. 
charges  and  ground  with  the  muller  down  for 
8  or  10  hours.  The  muller  is  then  raised  and 
from  900  to  1200  pounds  of  mercury  is  added  ; 
the  pan  continues  to  run  3  hours  more  with  the 
muller  raised.  The  tailing  from  the  concen- 
trate is  dewatered  and  passed  into  the  tube- 
mills  (26)  there  joining  the  mill-flow. 

The  tailing  from  the  Deister  tables  goes  to 
4  rectangular,  double-cone,  hydraulic  classi- 
fiers (23).  From  here  the  coarse  material  goes 
to  the  tube  mills  (26)  and  the  fine  direct  to 
the  cyanide  annex.     The  overflow  from  the 


classifiers  (23)  goes  to  three  Dorr  thickeners 
{28}  and  the  thickened  pulp  is  classified  into 
sand  and  slime,  the  former  going  to  vats  (J5), 
and  the  latter  to  Trent  agitators  (32)  arranged 
in  series.  The  Trent  agitator  is  a  flat-bottom- 
ed vat.  Circulation  is  eff^ected  by  means  of  a 
centrifugal  pump  which  draws  the  solution 
away  from  near  the  surface  and  delivers  it 
through  a  central  axis  into  four  arms  arranged 
about  18  in.  above  the  bottom.  These  arms 
have  each  a  row  of  nozzles  along  one  side 
and  the  issuing  jets  cause  them  to  revolve 
slowly.  The  final  discharge  from  No.  3  goes 
to  Moore  filters  (46).  The  Merrill  zinc-dust 
precipitation  process  is  employed  (44).  The 
overflow  from  the  Dorr  thickeners  goes  to  the 
Merrill  plant  also,  as  much  gold  being  removed 
as  possible.  It  is  interesting  to  compare  this 
method  of  treating  Cobalt  silver  ore  with  that 
adopted  at  the  McKinley-Darragh  mine,  de- 
scribed briefly  in  our  Precis  of  Technology. 

Complete  references  to  the  flow-sheet  are 
given  herewith  :  (7)  Mine-ore  bin  ;  (2)  gyratory 
crusher;  (J)  10  in.  elevator  ;  (-/)  Snyder  sam- 
pler 10%;  (5)  Blake  crusher  8  in.  by  12  in. ;  (6) 
Vezin  sampler  10%  ;  (?)  rigid  rolls  24  in.  by  12 
in.;  (8)  Vezin  sampler  10%  ;  (9)  two-compart- 
ment bin;  (70)  sample  bell  grinder ;  (7  7)  3  by 
10  ft.  trommel  ;  (72)  plunger  feeder  ;  (13)  30 
by  10  in.  spring  rolls  ;  (74)  8  in.  elevator;  (75) 
16  in.  belt  conveyor  ;  (16)  automatic  scale  ; 
(77)  16  in.  belt  conveyor  ;  (78)  automatic  trip- 
per ;   (79)  mill-ore  bin  ;  (20)  Challenge  feeder ; 

(27)  twenty  15001b.  stamps;  (22)  four  No.  2 
Deister  tables ;  (23)  four  Kirby  classifiers  ; 
(24)  3  by  3  ft.  equalizing  tank  ;  (25)  two  3  ft. 
dewatering  cones  ;  (26)  two  4  ft.  6  in.  by  18  ft. 
tube-mills  ;   (27)  8  by  54  in.  Frenier  pump ; 

(28)  three  24  by  10  ft.  Dorr  settlers  ;  (29)  8  in. 
elevator ;  {30)  three  Kirby  classifiers ;  (J7) 
equalizing  tank  ;  {32)  24  by  12  ft.  Trent  agita- 
tors ;  {33)  three  3  in.  Morris  agitating  pumps  ; 
{34)  three  3  in.  decantors  ;  (35)  24  by  6  ft.  sand 
vat ;  {36)  Price  centrifugal  pump  ;  (37)  clari- 
fying tank  ;  (38)  two  16  by  16  ft.  precipit,  soJ. 
tanks;  {39)  12  by  10ft.  waste  solution  tank; 
{40)  12  by  10  ft.  unprecip.  sol.  tank  ;  (47) 
Merrill's  zinc  feeder;  (42)  7  by  9  in.  triplex 
pump  ;  {43)  3  in.  centrifugal  pump  ;  {44)  two 
Merrill  filter-presses;  {45)  two  18  by  12  ft. 
solution  storage  ;  {46)  Moore  filter-press  ;  {47) 
two  7  by  10  in.  vacuum  pumps  ;  (48)  24  by 
20  ft.  water  storage  ;  (49)  8  by  10  ft.  equalizing 
tank  ;  (50)  5  ft.  grinding-pan  ;  (57)  8ft.  settler  ; 
(52)  54  in.  by  10  ft.  amalgamating  plate  ;  (53) 
6  by  6  ft.  settling  tank  ;  (.54)  12  by  48  in.  re- 
torts ;  (55)  condensers;  (56)  Steel- Harvey 
furnaces. 


SEPTEMBER,    1911 


207 


FLOW-SHEET    OF    THE    NOVA-SCOTIA    CYANIDE   PLANT,   COBALT. 


208 


THE    MINING    MAGAZINE 


PERSONAL 

G.  B.  Adeney  sailed  on  August  23  for 
Cape  Town  on  his  way  to  Johannesburg. 

J.  G.  Bower  is  in  London  on  his  way  from 
Mexico  to  South  Africa. 

J.  E.  Breakell  is  at  Tegucigalpa,  in 
Honduras. 

C.  R.  Corning  sailed  for  New  York  on 
the  Amerika  on  August  30. 

C.  D.  Cosby  is  in  the  island  of  Sakhalin. 

A.  Spencer  Cragoe,  of  Bruce  Marriott 
&  Co.,  sailed  for  Brazil  on  September  8. 

Edward  H.  Croghan,  lately  on  the  Rand, 
is  at  Cambridge. 

George  A.  Denny  is  expected  in  London 
from  Mexico  on  September  14. 

R.  Farina,  for  Pearse,  Kingston  &  Browne, 
is  on  his  way  to  Central  Siberia. 

Rowland  Feildixg  left  for  Newfound- 
land on  August  26. 

George  H.  Garrey  has  opened  an  office 
at  San  Francisco  as  a  consulting  mining  ge- 
ologist. 

Ernest  Grave  has  left  Pinos  and  is  now 
at  Tampico,  Mexico. 

Harry  D.  Griffiths,  the  manager  of  the 
Tronoh  Mines,  sailed  for  the  Malay  States  on 
September  2. 

T.  M.  Hamilton,  formerly  at  Asientos,  is 
now  superintendent  of  the  American  Smelting 
Co.'s  plant  at  Charcas,  Mexico. 

KUNO  B.  Heberlein  is  here  from  Mapimi, 
Mexico. 

W.  M.  Henderson  Scott  is  here  from 

Colorado. 

C.  S.  Herzig  is  at  Iquitas,  Peru. 

Ross  B.  Hoffmann  and  Scott  Turner 
sailed  for  New  York  on  September  8. 

H.  C.  Hoover  and  A.  C.  Beatty  left  for 
Kyshtim,  Siberia,  on  September  6. 

J.  D.  Hubbard  is  now  superintendent  for 
the  Chosen  Mining  Co.,  in  Korea. 

Louis  D.  Huntoon,  until  recently  pro- 
fessor of  mining  and  metallurgy  in  Yale  Uni- 
versity, has  opened  an  office  at  42  Broadway, 
New  York. 

H.  H.  Johnson  and  J.  I.  Hoffman  have 
gone  into  partnership,  with  offices  at  216 
Moorgate  Station  Chambers,  E.C. 

John  T.  Keating  has  gone  to  Kano,  in 
Northern  Nigeria. 

F.  F.  Kett  is  in  London,  on  his  return 
from  Chile. 

Frank  Langford  has  returned  from 
Chile  and  is  at  Eureka,  California. 

Thos.  H.  Leggett  is  in  the  Yukon  Ter- 
ritory. 


Ernest  Levy  has  returned  to  British 
Columbia. 

A.  G.  Macdonald,  of  Dunedin,  N.Z.,  is 
in  London. 

George  Macfarlane  has  been  appoint- 
ed manager  for  the  Wallis  Syndicate  in  West 
Africa. 

C.  H.  Macnutt  left  London  for  Buenas 
Ayres  on  August  4  to  resume  charge  of  the 
Poderosa  mine,  in  Chile. 

Edward  T.  McCarthy  has  returned  from 
Porcupine. 

J.  W.  Mercer  is  in  the  Idatarod  district, 
Alaska. 

A.  E.  Parker  has  gone  to  Medellin,  in 
Colombia. 

Cyril  E.  Parsons  is  at  Bulawayo. 

Walter  G.  Perkins  has  returned  from 
Kyshtim. 

Frank  H.  Probert  was  at  Cananea, 
Mexico,  in  August. 

Thomas  Pryor  sailed  on  September  9  for 
India,  to  be  surveyor  of  the  Ooregum  mine. 

C.W.  Purington,D'ArcyWeatherbe, 
Norman  C.  Stines,  W.  H.  Knox,  and  H. 
G.  Hann  are  examining  dredging  areas  in 
Eastern  Siberia. 

Thomas  T.  Read,  associate  editor  of  the 
Mining  and  Scientific  Press,  was  recently 
at  Ely,  Nevada. 

Forbes  Rickard  is  at  Valdez,  Alaska. 

James  A.  Rickard,  of  Toulouse,  recently 
manager  of  the  Villaniere  gold  mines  in 
France,  made  a  visit  to  London. 

W.  Roberts  is  in  Egypt. 

F.  F.  Sharpless  was  recently  at  Seward, 
Alaska. 

S.  F.  Shaw  has  resigned  as  manager  of  the 
Montezuma  Mines  of  Costa  Rica. 

A.  L.  Simon  has  returned  from  the  Ural 
Mountains. 

Richard  B.  Stanford  concluded  his  visit 
in  London  and  is  now  at  New  York. 

Henry  F.  Strangways  is  in  the  Moro- 
cocha  district  of  Peru. 

A.  Ernest  Thomas  is  in  Portugal.  He 
expects  to  return  to  London  at  the  end  of 
September. 

E.  COPPEE  Thurston  has  come  from  New 
York  to  accept  the  post  of  mining  engineer  to 
A.  Goerz  &  Co.,  in  London. 

H.  L.  Twite,  of  Twite  &  Steinhart,  was 
in  Norway  recently. 

H.  H.  Webb  sails  for  New  York  on  Sep- 
tember 29. 

Morton  Webber  is  in  Mexico. 


THE  FINANCE  OF  A  MINE.    IV. 

By  M.  H.  BURNHAM. 


THE  first  article  of  this  series  dealt  with 
the  basic  concepts  of  investment,  namely, 
the  necessity  for  considering  the  return 
of  the  capital  and  a  rate  of  interest  commen- 
surate with  the  risk.  The  second  paper  de- 
veloped these  premises  as  applied  to  the  ore 
reserve  and  sought  to  prove  that  the  ore  in  a 
mine  should  be  valued  on  the  same  principle, 
that  is,  the  risk -rate  should  vary  for  each 
block  inversely  with  the  available  data  or 
number  of  sample  sections.  The  expansion 
of  this  idea  also  demonstrated  the  need  for 
regarding  as  a  reserve  the  ore  lying  below 
the  deepest  level  to  a  point  governed  by  the 
above  idea  and  determined  by  the  formula 
submitted.  The  third  article  dealt  with  the 
ore  still  below  the  above  point,  that  is,  the 
possibilities  of  the  mine,  and  sought  to  estab- 
lish a  "unit  of  possibility"  wherewith  to  com- 
pare the  economic  magnitudes  of  different  de- 
posits, aside  from  the  reserve  in  each,  thereby 
furnishing  a  criterion  of  valuation  practice. 

As  will  have  been  seen,  all  the  foregoing  is 
the  outcome  of  a  development  of  the  simple 
business  axiom  that  the  greater  the  risk  the 
greater  the  rate  of  interest  to  be  demanded, 
whether  the  comparison  be  between  different 
financial  ventures  or  blocks  of  ore  in  the  same 
mine  in  different  stages  of  development.  The 
present  and  succeeding  articles  take  up  the 
above  concept  in  conjunction  with  that  of  de- 
ferment, which  last  is  of  course  nothing  more 
than  the  demand  that  the  returns  when  avail- 
able shall  make  up  the  losses  due  to  the  non- 
payment of  dividends  during  the  deferred 
period  and  extend  the  application  of  this  prin- 
ciple, with  the  one  foregoing,  to  the  valuation 
of  each  block.  The  present  chapter  deals 
with  the  practical  significance  of  what  is 
known  in  actuarial  parlance  as  deferred  an- 
nuities ;  this,  if  the  risk-rate  idea  be  accepted, 
assumes  a  role  the  importance  of  which  ap- 
pears to  have  been  entirely  overlooked  in  metal 
mining,  though  recognized  in  Early  Victorian 
coal-valuation  practice. 

Unpleasant  as  may  be  the  admission,  the 
modern  engineer  has  perforce  to  allow  that 
our  grandfathers  had  a  firmer  hold  on  the 
economic  bases  of  finance  than  we  have.  So 
badly  weighted  are  the  curriculums  of  techni- 
cal institutions  that  men  are  turned  out  not  only 
ignorant  of  the  basis  of  industrial  finance  but 


too  often  sadly  wanting  in  a  sense  of  economic 
proportion.  As  a  matter  of  fact  the  ordinary 
engineer  when  first  launched  from  a  School  of 
Mines  is  generally  a  pseudo-scientific  dreamer, 
and  in  spite  of  wonderful  opportunities  in  the 
way  of  varied  experience,  it  requires  many 
years  to  counteract  the  vicious  defects  of  his 
early  instruction.  As  mentioned  before,  al- 
though the  engineer's  ordinary  work  may  be 
little  concerned  with  the  economics  of  finance, 
when  he  has  to  advise  in  a  negotiation  or  is 
consulted  with  regard  to  the  value  of  shares 
the  whole  subject  calls  for  the  closest  atten- 
tion. Furthermore,  the  growing  practice  of 
placing  engineers  on  the  directorates  of  public 
companies  confirms  the  above  view  with  re- 
gard to  the  need  for  a  knowledge  of  finance, 
and  the  choice  of  men  of  character  and  ability 
indicates  a  tendency  to  allow  the  ordinary 
tenets  of  commercial  faith  to  supersede  the 
exigencies  of  an  optimism  nicely  surcharged 
for  promotional  purposes. 

As  indicated  before,  the  significance  of  de- 
ferment is  sadly  overlooked  not  only  in  the 
case  of  the  simplest  calculations  but  in  more 
complex  problems,  among  which  might  be 
mentioned  those  of  industrial  ethics.  For  in- 
stance, the  not  uncommon  phenomenon  of  the 
financially  vicious  forsaking  devious  ways  for 
the  paths  of  financial  virtue  may  be  said  to  be 
a  deferment  of  profit  to  be  secured  later  in  the 
shape  of  civic  honour,  titled  or  otherwise. 
According  to  my  own  observation,  the  shares 
or  interests  taken  by  promoters  in  many  min- 
ing flotations  is  too  small  when  one  considers 
the  inevitable  loss  of  time  and  money  incurred 
by  them  in  fruitless  examinations.  Twenty 
per  cent,  may  not  be  too  much  in  the  case 
of  a  successful  venture  to  recoup  the  many 
failures,  but  the  feature  that  tends  to  brand 
even  fair  mining  finance  as  public  exploita- 
tion is  the  sale  of  promoting  shares  as  soon  as 
issued  ;  in  other  words,  the  failure  to  apply 
the  deferment  principle  to  realization.  The 
inertia  of  public  interest  once  set  in  motion  is 
considerable  and  often  permits  the  sale  of  pro- 
moting shares  immediately  after,  if  not  with, 
those  issued  for  working  capital.  Manifestly, 
by  the  immediate  sale  of  their  holdings  at 
each  flotation  promoters  stand  to  win  though 
the  mine  should  fail ;  hence  there  is  no  equality 
of  risk. 


209 


210 


THE  MINING  MAGAZINE 


The  recognition  of  the  essential  soundness 
of  the  deferment  principle  is  illustrated  in 
many  syndicate  flotations  where  the  prospec- 
tus calls  for  the  return  of  the  cash  capital 
before  dividends  may  be  available  for  pro- 
moting or  bonus  shares.  This  does  not  over- 
come the  iniquity  of  immediate  realization  of 
promoting  shares,  which,  in  the  case  of  syndi- 
cate arrangements  between  financiers  who  also 
personally  find  working  capital,  is  overcome 
by  a  pooling  arrangement.  Such  a  method 
does  not,  however,  apply  to  public  issues,  and 
yet  there  is  an  insistent  demand  for  some 
standard  of  sound  finance  touching  the  point. 
Only  two  attempts  at  a  solution  of  the  prob- 
lem are  known  to  me,  one  being  the  payment 
to  promoters  of  their  out-of-pocket  expenses 
from  the  cash  capital  and  the  withholding 
of  promoting  shares  until  the  cash  shares  have 
received  at  least  100%  in  dividends.  A  mealy- 
mouthed  pose  of  virtue  sometimes  appears 
when  it  is  stated  that  the  promoting  shares 
will  not  be  sold  until  the  market  quotation  of 
the  cash  capital  shares  have  increased  by,  say, 
25%.  As  most  people  have  at  least  rudimen- 
tary ideas  of  the  influences  occasionally  gov- 
erning the  market  quotations,  this  bait  will 
convey  little  beyond  showing  a  paltry  effort 
at  throwing  dust  into  the  eyes  of  those  seek- 
ing some  sign  of  good  faith.  The  second  and 
most  practicable,  yet  withal  equitable,  plan 
would  seem  to  be  that  of  allotting  the  pro- 
moting shares  only  when  the  present  value  of 
the  ore  reserve  represents  the  total  nominal 
capital  (issued)  of  the  company.  Evidently 
the  pressure  on  the  engineer  who  values  the 
ore  reserve  would  be  serious  in  some  cases, 
and  such  a  plan  might  be  workable  only  if  a 
definite  method  of  valuation  be  accepted. 

That  this  deferment  idea  is  not  merely  an 
academic  concept,  having  no  expression  in 
practical  finance,  is  shown  by  the  London 
Stock  Exchange  regulation  that  dealings  in 
vendor  and  promoting  shares  are  forbidden 
for  six  months  after  those  representing  the 
cash  capital.  Clearly  this  is  a  recognition  of 
the  lack  of  parity  between  the  shares  and  is 
an  effort  to  protect  the  bona  fide  investor, 
hence  in  the  interest  of  mining  adventure,  as 
distinct  from  market  gambling. 

This  consideration  of  promoting  profits  is 
usually  avoided  with  painful  pertinacity  by 
engineers  ;  yet  it  must  be  faced,  not  only 
when  passing  upon  the  real  value  of  mining 
shares  but  when  acting  as  negotiators  in  foreign 
countries.  With  that  habit  of  making  sweep- 
ing generalization  or  crude  formulation,  so 
common  a  defect  of  the  scientifically  educa- 


ted, engineers  are  prone  to  take  extreme  views 
of  promotion  though  a  casual  acquaintance 
will  usually  convince  them  of  the  special 
ability  required  and  the  number  of  cases  where 
those  promoting  have  stuck  to  a  principle  by 
refraining  from  taking  tempting  profits.  While 
undoubtedly  the  great  number  of  mining  swin- 
dles accounts  for  the  extreme  difficulty  of 
raising  capital  at  times,  even  for  the  most 
promising  venture,  I  hold  that  the  mining  en- 
gineer is  responsible  for  fully  one  half  of  these 
fiascoes  by  reason  of  his  inability  to  exercise 
a  sense  of  economic  proportion  in  valuation  ; 
also  because  of  his  lack  of  sound  ideas  touch- 
ing finance,  not  to  mention  a  haste  to  sell 
shares  received  in  part-payment  of  fees.  As 
in  other  lines  of  industry  the  hope  of  ulti- 
mately winning  a  social  and  civic  position  is 
the  real  deterrent  to  malpractice,  so  the  most 
potent  force  tending  to  keep  the  engineer  up 
to  a  high  standard  of  effectiveness,  moral  and 
technical,  is  the  opinion  of  the  professional 
world. 

It  will  be  seen  that  the  different  kinds 
of  shares  usually  issued  are  distinguished  by 
their  incorporation  of  one  or  both  of  the  above 
principles,  namely,  varying  risk-rates  and 
times  of  deferment.  For  example,  deben- 
tures by  common  consent  and  current  practice 
imply  provision  for  their  amortization,  neces- 
sarily a  charge  upon  the  known  assets ;  they 
thereby  incur  less  risk  and  receive  a  lower 
rate  of  interest.  The  debenture  right  of  fore- 
closure in  default  of  interest  is  also  a  recog- 
nition of  the  cumulative  principle.  Cumula- 
tive preference  shares  while  ordinarily  carry- 
ing no  amortization  privilege,  not  only  aim  to 
have  this  compensated  by  a  higher  annual  re- 
turn commensurate  with  the  greater  risk,  but 
call  for  interest  from  the  time  of  issue,  even 
should  dividends  be  deferred  or  suspended. 

From  the  above  is  seen  the  recognition  in 
financial  practice  of  the  equity,  not  only  of 
ensuring  a  return  of  the  capital  when  the  risk- 
rate  is  low  and  the  graduation  of  the  latter  to 
meet  varying  risks,  but  the  incorporation  of 
the  deferment  principle  in  cumulative  shares. 

We  may  then  point  out  to  reporting  engi- 
neers that  by  failing  to  recognize  the  above 
two  great  principles  when  valuing  reserves, 
we  flout  not  only  sound  theory  but  current 
financial  practice.  Is  it  a  wonder  that  intelli- 
gent financiers  usually  regard  us  as  dreamers, 
incompetents,  or  charlatans  when  we,  the 
supposedly  scientifically  educated,  ignore  the 
very  elements  of  business  knowledge  ?  One 
may  say  that  when  engineers  act  as  negotia- 
tors the  practical  application  of  the  deferment 


SEPTEMBER,    1911 


211 


principle  is  the  surest  gauge  of  their  business 
abihty  as  expressed  in  the  terms  of  the  pur- 
chase price.  For  instance,  where  a  single  cash 
payment  for  a  property  exceeds  the  present 
value  of  the  ore  reserve,  the  excess  is  the 
price  paid  for  possibility  only  ;  in  other  words, 
is  the  sum  risked.  Without  changing  the  ulti- 
mate purchase  price  but  by  simply  deferring 
payment  for  a  sufficient  time  in  which  to  de- 
velop another  level,  the  amount  risked  may  be 
reduced  to  the  cost  of  such  development.  The 
merest  greengrocer  before  making  a  payment 
in  purchase  of  a  corner  stall,  will  take  it  over 
for  a  time  in  which  to  verify  his  hopes  of  pro- 
fit, yet  no  such  simple  business  acumen  seems 


the  mortgage  is  made  equal  to  the  dividends 
paid  by  a  property  productive  at  the  time  of 
purchase  and  the  first  amortization  payment 
is  so  timed  as  to  admit  of  adequate  develop- 
ment before  falling  due,  the  original  owners 
have  nothing  to  lose  in  the  way  of  dividends 
nor  of  property,  yet  they  stand  to  gain  by 
developments  underground  should  the  first 
mortgage  payment  fail.  Evidently  this  use  of 
a  debenture  issue  in  the  place  of  cash  for  a 
property  is  of  quite  a  different  character  from 
that  ordinarily  obtaining  where  money  is 
raised  for  payment  to  vendors  or  for  working 
capital  under  the  assumption  that  there  is  no 
risk  to  capital  or  likelihood  of  loss  of  interest. 


Table  V 

—  Debenture 

Analysis. 

1 

2 

3 

4 

5 

6 

7 

8 

9     . 

10 

11 

12 

u 

CO 
(U 

>. 

o 
a 

c 
Q 

Debenture  pay- 
ments due  per 
prospectus 

Factor  from  table 
of  risk-rate  3% 

Total  income  from 
estimated  reserve 

V 

u  •an 

•a 

c 

O  o 

dj  o 

T3  — . 

5^ 

Half  balance  of 

dividends  for 

extra  redemption 

of  debentures 

Total  payments  on 

debenture  and 

interest  possible 

as  per  prospectus 

a 

CO 

a, 

Available 
for  dividends 
on  1,100,000  ordin- 
ary shares 

Present  value  of 
amounts  available 
for  dividends  with 

risk-rate  at  3% 

£ 

£ 

/ 

£ 

£ 

£ 

£ 

£ 

£ 

1910 

1 

30,000 

094340 

260,000 

230,000 

230,000 

— 

30,000 

28,000 

230,000 

217,000 

1911 

2 

30,000 

0  89000 

483,000 

403,000 

202,000* 

& 
110,000 
146,000 

6,000 

30,000 

27,000 

312,000 

278.000 

1912 

3 

186,000 

0  83962 

270,000 

140,000 
& 

0 

186,000 

156.000 

146,000 

131,000 

1913 

4 

121,000 

079209 

270,000 

6,000 
149.000 

149,000 

0 

121,000 

96,000 

149.000 

118.000 

1914 

5 

115,000 

0  74726 

22,000 

0 

0 

0 

22,000 

16,400 

0 

0 

Total 


1,305,000  928.000     837,000       6.000       389,000    323.000    837,000     744.000 

Paid  for  debentures   487.000       —       1,100.000 


Loss  or  difference     164,000 


356,000 


*  All  profits  before  June  1911  other  than  debenture  interest  to 
dividends  before  further  debenture  amortization  of  £6000 

to  be  expected  of  engineers.  We  may  feel  a 
thrill  of  righteous  indignation  with  the  man 
who  classes  granite  with  diorite,  or  a  rhyolite 
as  andesite,  yet  we  mete  out  no  censure  to 
those  who  outrage  the  most  elementary  canons 
of  common  sense  in  the  purchase  of  a  mine. 
The  value  of  a  debenture  issue  as  a  valuable 
adjunct  to  mining  negotiation,  whereby  defer- 
ment of  payments  to  several  vendors  may  be 
secured,  is  seldom  utilized  though  its  basic 
element,  the  mortgage,  is  an  instrument  recog- 
nized in  all  countries.     Where  the  interest  on 


go  to  dividends;  next  £80,000  to  debentures  and  £110,000,  to 
,  which,  with  the  £"50,000,  is  payable  at  end  of  \9\2. 

Where  mining  debentures  are  accompanied 
by  bonus  shares,  thereby  making  the  former 
speculatively  attractive,  the  tendency  is  to 
confuse  the  two  principles  of  safety  and  specu- 
lation, and  a  careful  analysis  of  the  terms  of 
the  debenture  issue  is  necessary  to  weigh  the 
advantages  peculiar  to  each. 

The  caseof  the  Camp  Bird  issue  made  at  the 
time  of  the  purchase  of  the  Santa  Gertrudis 
property  is  an  illuminating  case  from  recent 
practice,  as  the  above  analysis  in  Table  \  . 
will  show.     It  is  based  on  published  data  only, 


212 


THE    MINING    MAGAZINE 


no  private  information  being  used.  ^500,000 
of  debentures  were  offered  on  the  first  of  Janu- 
ary 1910  at  97?  bearing  6%  per  annum  and  re- 
deemable at  110;  ^150,000  for  redemption  pur- 
pose to  be  paid  three  years  later;  also  ^100,000 
and  interest  on  outstanding  debentures  to  be 
paid  each  year  following.  Half  of  the  profits 
made  later  than  the  middle  of  191 1,  after  pay- 
ing 20%  interest  on  a  capital  of  ^1,100,000, 
was  to  be  set  aside  for  further  redemption  of 
debentures.  The  dates  of  receipts  and  amounts 
of  annual  profits  as  per  the  estimates  in  the 
propectus  are  set  out  m  the  first  and  fifth 
columns  of  Table  V. ;  columns  1,  2,  and  3  give 
the  dates  of  the  proposed  certain  debenture 
payments,  while  column  8  gives  the  contingent 
redemption  allowance.  Column  9  sets  out  the 
total  debenture  payments  and  column  10  their 
present  value  up  to  the  time  of  the  exhaustion 
of  the  estimated  ore  reserve.  A  further  con- 
sideration was  offered  the  purchasers  of  the 
debentures  in  the  shape  of  an  option  for  three 
years  on  ;^250,000  of  ordinary  shares  at  35s. 
per  share.  By  an  analysis  of  Table  V.  it  is 
seen  that  the  debenture  subscribers  are  in- 
vited to  lose  ;^164,000  out  of  their  ^487,000, 
unless  orebodies  were  found  beyond  those  on 
which  the  engineers  based  their  estimate,  al- 
though theirestimatefor  one  mineof  the  two  al- 
lowed for  ore  over  100  ft.  below  that  of  the  deep- 
est level,  the  other  mine  being  acknowledged 
to  be  nearing  exhaustion.  In  other  words,  the 
debenture-holders,  instead  of  having  the  re- 
serve set  aside  for  their  use  and  protection, 
were  asked  to  risk  ;^164,000,  receiving  there- 
for only  6%  per  annum  during  the  same  time. 
In  the  default  of  addition  to  the  reserve  they 
would  lose  nearly  a  quarter  of  their  money, 
and  even  if  more  ore  were  found  they  could 
hope  to  receive  for  their  risk  only  the  stipu- 
lated 6%  unless  bonanzas  sufficiently  rich  were 
struck  to  raise  the  price  of  the  ordinary  shares 
above  35s.,  thereby  enabling  them  to  make  a 
profit,  but  only  by  the  amount  the  shares 
might  exceed  that  figure.  Expressed  other- 
wise, the  ordinary  shareholder  might  reap  the 
benefit  of  the  new  orebodies,  but  so  long  as  the 
profits  made  did  not  justify  more  than  35s. 
for  the  ordinary  shares  the  debenture  holders 
could  expect  only  their  6%  annually.  In  pass- 
ing it  may  be  added  that  the  above  issue  of 
debentures  has  been  called  in,  leading  one  to 
suppose  that  its  defects  have  become  evident 
upon  closer  scrutiny. 

The  next  article  will  deal  with  the  relative 
promise  of  company  and  syndicate  flotations, 
a  subject  involving  to  a  large  extent  the  dif- 
ference between  investment  and  speculation. 


The  latter  is  the  very  life  of  both  science  and 
industry.  This,  however,  does  not  hold  true 
of  market  gambling,  a  subject  that  though  it 
concerns  even  the  sound  financier,  is  too 
complicated  for  the  engineer,  however  versed 
he  may  be  in  the  theoretical  economics  of 
finance. 


The  Chino  Copper  Mine. — New  Mexico 
has  not  kept  pace  with  Arizona  in  mineral 
production,  despite  abundant  and  varied  re- 
sources. The  new  movement  of  capital  into 
the  southwest  of  the  United  States  in  search 
for  copper,  has  begun  to  be  felt  even  in  the 
land  of  sleep,  sunshine,  and  silence,  where 
people  are  prone  to  live  as  their  ancestors  did 
before  the  troublesome  '  gringoes  '  came  into 
the  country.  The  Chino  mine  is  in  a  very 
old  mining  district,  associated  with  the  old 
name  Santa  Rita  and  many  of  the  great  names 
of  American  mining.  Haggin  and  Hearst 
added  to  their  fortunes  here.  The  Confeder- 
ate armies,  short  of  lead,  cast  copper  bullets 
from  Chino  ore,  and  Thomas  Lawson,  the 
irrepressible,  drew  from  it  inspiration  for  his 
most  elaborate  masterpiece  of  prose  fiction. 
Copper  was  produced  here  when  transporta- 
tion was  by  mule  to  the  City  of  Mexico,  and 
in  the  midst  of  the  modern  works  one  of  the 
towers  of  an  old  adobic  fort  erected  as  a  de- 
fence against  the  Apaches,  looks  down  on 
snorting  steam-shovels  and  impatient,  buzzing 
autos.  The  fort,  by  the  way,  serves  now  the 
prosaic  purpose  of  a  place  where  Mexicans 
and  Indians  having  imbibed  too  freely  of  the 
white  man's  liquor,  may  cool  off  while  waiting 
the  slow  revolution  of  the  wheels  of  justice. 
The  presence  of  old  workings  adds  more  than 
picturesqueness  to  the  new  undertaking.  It 
made  possible  extensivesamplingunderground 
in  advance  of  the  steam-shovels,  and  the  easy 
checking  of  churn-drill  holes.  The  Chino, 
therefore,  more  than  any  other  of  the  new 
copper  mines,  has  confirmation  of  the  results 
of  its  drilling.  It  is  estimated  that  45,238,231 
tons  of  ore  averaging  2'3%  copper  are  avail- 
able in  this  property,  and  that  of  this  amount 
71%  may  be  mined  by  steam-shovel.  The 
original  source  of  the  copper  is  not  certain. 
Its  present  position  is  secondary.  In  one 
particular  it  differs  from  that  at  the  other 
porphyry  copper  mines,  namely,  in  the  large 
amount  of  metallic  copper  present.  This  has 
made  the  sampling  unusually  difficult  and  has 
required  special  care  in  estimating.  A  con- 
centrating plant  has  been  built  at  Hurley, 
about  ten  miles  from  the  mine  where  ample 
water  and  ground  are  available. 


MINERAL  RESOURCES  OF  CENTRAL  AFRICA 


By  OWEN  LETCHER. 


ONLY  within  the  past  decade  has  Central 
Africa  come  to  possess  any  measure  of 
mining  importance.  The  days  when 
this  vast  tract  of  the  world's  surface  between 
the  Zambesi  and  the  Nile  was  regarded  as  the 
particular  domain  of  black  men  and  wild  beasts, 
bold  explorers,  and  ambitious  missionaries,  are 
fast  disappearing.  A  line  of  railway  now 
stretches  northward  to  Elizabethville  in  the 
Belgian  Congo ;  another  is  hastening  south- 
ward from  Khartoum.  Feeder  lines  branch 
east  and  west  to  pick  up  trade  and  carry  pro- 
ducts to  the  coast.  The  great  lakes  and  rivers 
have  modern  steam-boats  plying  on  them  and 
give  further  help  to  the  opening  up  of  lands 
recently  only  associated  with  the  names  of 
Livingstone  and  Stanley.  At  this  juncture, 
therefore,  it  may  be  of  some  interest  to  take 
stock  of  the  mineral  resources  of  the  Great 
Interior  as  far  as  they  are  known,  and  briefly 
to  discuss  the  potentialities  of  the  mineral  belts 
so  far  discovered. 

The  mining  areas  situated  in  the  Katanga  re- 
gion of  the  Belgian  Congo  and  controlled  by  the 
Tanganyika  Concessions  and  the  Compagnie 
Miniere  de  Haut  Katanga  loom  large  in  the 
scope  of  this  article.  Few  undertakings  fin- 
anced by  British  capital  and  engaged  in  the 
exploitation  of  minerals  in  a  foreign  country 
have  received  more  searching  and  more  de- 
served criticism.  Vast  sums  of  money  are 
involved  in  the  Katanga  scheme  of  mine  de- 
velopment and  in  the  subsidiary  projects  of 
railway-building.  One  of  the  latter  under- 
takings has  achieved  its  objective  at  Eliza- 
bethville, 7  or  8  miles  from  the  Star  of  the 
Congo  mine.  The  other  project,  that  of  con- 
necting Lobito  Bay  on  the  West  Coast  with 
the  mineral  belt,  is  proceeding  but  slowly.  A 
brief  consideration  of  the  geographical  position 
of  the  Katanga  with  regard  to  existing  trade- 
routes  and  the  ports  of  Europe  and  America 
makes  it  quite  clear  that  Lobito  Bay  is  the 
commercial  key  to  Central  Africa.  But  con- 
struction of  the  route  from  the  West  Coast 
(1200  miles  distant)  has  proved  a  bigger  pro- 
position than  was  anticipated,  and  further  large 
sums  of  money  must  be  expended  on  the  com- 
pletion of  the  line  and  the  proper  equipment 
of  the  port  itself  before  it  can  claim  the  trade 
of  the  interior.  Completely  to  construct  the 
line  and  equip  the  port,  a  sum  of  ten  millions 


sterling  is  required.  And  when  this  project 
is  consummated  the  Lobito  Bay  route  will 
have  to  contend  with  serious  competition  from 
the  Belgian  as  well  as  the  British  trade-routes. 
For  the  time  being  the  British  South  Africa 
Company  and  the  Port  of  Beira  in  Portuguese 
East  Africa  are  reaping  the  benefit  of  the  de- 
velopment of  Katanga.  Meanwhile  Belgian 
financiers  and  the  Government  of  the  Congo 
State  are  making  strenuous  endeavours  to  di- 
vert trade  to  the  navigable  waters  of  the  Congo 
river  and  so  confine  Katanga's  imports  and  ex- 
ports to  Belgian  territory.  It  will  be  interest- 
ing to  watch  the  progress  of  the  rate-war  be- 
tween these  three  competitive  routes, assuming 
that  the  trade  of  Katanga  is  sufficiently  large 
to  make  the  contest  noteworthy.  That  in  the 
southern  portion  of  the  Congo  State  there  are 
vast  cupriferous  deposits  is  not  doubted,  but 
that  the  properties  of  the  Tanganyika  Conces- 
sions and  the  associated  Belgian  corporations 
are  about  to  dominate  the  copper  trade  of  the 
world,  as  some  have  stated,  is  an  anticipation 
apparently  unwarranted. 

The  conditions  in  the  Katanga  are  not  paral- 
lelled elsewhere  in  copper  mining.  Many 
millions  of  tons  of  carbonate  ore  have  been 
proved  in  the  hills  and  kopjes  that  form  the 
Katanga  mineral  belt,  but  the  economic  prob- 
lem remains  unsolved.  In  some  cases  the 
cupriferous  beds  may  extend  to  considerable 
depth,  though  in  the  majority  of  the  mines  the 
beds  are  not  likely  to  be  found  far  down  on 
account  of  folding  of  the  strata.  Owing  to  the 
great  distance  of  the  mines  from  the  coast,  the 
shipment  of  ore,  even  with  the  Lobito  line 
completed,  would  be  out  of  the  question, 
especially  as  the  smelter  charges  on  such 
highly  silicious  ore  would  be  high.  The  Tan- 
ganyika problem  resolves  itself  then  into  the 
profitable  smelting  of  the  ore  on  the  spot.  At 
any  time  some  new  and  epoch-making  dis- 
covery in  the  metallurgy  of  copper  may  com- 
pletely revolutionize  the  position,  but  it  is  un- 
wise to  depend  upon  the  unexpected.  The 
management  of  the  Tanganyika  Concessions 
for  a  long  while  has  tiad  the  smelting  problem 
under  consideration,  but  its  policy  has  not  been 
disclosed,  and  it  is  rumoured  now  that  tlie  pre- 
liminary operations  at  the  Lubambashi  smel- 
ter, 12  miles  from  the  Star  of  the  Congo  mme, 
have  not  resulted  satisfactorily.     It  is  known 


213 


214 


THE    MINING    MAGAZINE 


too  that  a  considerable  divergence  of  opinion 
existed  between  an  experienced  American 
metallurgist,  who  was  engaged  to  proceed  to 
the  Tanganyika  Concessions,  and  the  local 
management  on  the  question  of  ore  treatment ; 
so  much  so  that  the  American  investigator 
severed  his  connection  with  the  company. 
Blast-furnace  smelting  appears  today  to  be 
the  only  really  proved  and  reliable  process 
suitable  for  the  Tanganyika  ores.  In  this 
connection  much  depends  therefore  on  the  cost 
of  bringing  coke  to  the  Katanga  smelter.  De- 
spite the  statements  that  have  been  made  from 
time  to  time  as  to  the  suitability  of  South 
African  coal  for  coking  purposes,  it  does  not 
seem  that  anything  satisfactory  is  obtainable 
m  the  sub-continent.  The  people  controlling 
the  Wankie  colliery  appear  to  be  particularly 
silent  and  inactive  in  this  connection,  and  it 
would  be  wholly  premature  to  say  anything 
regarding  the  possibilities  of  the  Luano  Valley 
coalfields  in  northwestern  Rhodesia,  southeast 
of  Broken  Hill,  Avhich  are  now  being  exploited 
by  the  Rhodesia- Katanga  Junction  Railway 
Co.  The  Tanganyika  Concessions  recently 
imported  a  large  quantity  of  coke  from  Europe, 
the  cost  to  the  company  when  delivered  at 
Katanga  being  something  like  ^13  per  ton. 
Looking  at  the  problem  broadly  it  would  ap- 
pear that  on  account  of  the  large  percentage 
of  flux  required  by  these  ores  and  the  heavy 
cost  of  the  coke  to  be  used  in  smelting  them, 
the  production  of  copper  would  be  so  expen- 
sive that  high-grade  ore  only  could  be  profit- 
ably handled.  These  facts,  taken  in  conjunc- 
tion with  the  vast  sums  of  money  necessary  to 
complete  the  railway  to  the  coast,  and  to  con- 
struct branch  lines  to  the  several  mines  and 
the  flux  deposits,  do  not  indicate  that  the  Tan- 
ganyika Concessions  will  be  producing  any 
large  quantity  of  copper  ore  within  the  next 
decade,  and  it  is  likely  to  be  a  considerable 
time  before  the  production  of  Congo  copper 
ore  exerts  any  appreciable  influence  on  the 
metal  market. 

In  addition  to  copper  it  is  known  that  gold, 
tin,  platinum,  and  diamonds  have  been  found 
in  the  Southern  Congo.  The  Ruwe  goldfield, 
however,  is  now  unproductive,  and  it  is  doubt- 
ful whether  the  remaining  gravel  is  worth 
washing.  This  gravel  results  from  the  ero- 
sion of  a  bed  of  sandstone  contained  in  the 
formation  capping  the  escarpment  on  which 
the  mine  is  situated.  Several  shafts  have  been 
sunk  into  the  sandstone  bed  itself  and  it  has 
been  reported  that  the  ground  opened-up  car- 
ries gold,  platinum,  and  palladium,  equivalent 
to  about  1 1  dwt.  of  gold  per  ton,  but  consider- 


able difficulty  would  be  experienced  in  separ- 
ating these  metals.  The  latest  flotation  of  the 
Tanganyika  group  is  styled  the  Compagnie 
Miniere  de  Kindelungu  with  a  capital  of 
2,500,000  f.  The  avowed  object  of  this  com- 
pany is  to  exploit  a  concession  in  the  vicinity 
of  the  Kindelungu  mountains  and  which  is 
said  to  yield  diamonds.  Cassiterite  occurs  in 
the  Bussanga  district  but  hitherto  alluvial  de- 
posits only  ha\e  been  worked.  Rumour  has 
it  that  a  discovery  of  cassiterite  in  a  lode-for- 
mation has  been  made  to  the  north  of  Bus- 
sanga, but  as  yet  nothing  definite  is  known. 

The  Congo  State  has  rich  mineral  tracts 
other  than  those  now  being  exploited  in  Ka- 
tanga. In  the  mid  -  eastern  portion  of  the 
territory  and  in  close  proximity  to  the  Uganda 
frontier  a  rich  gold  deposit  is  being  opened  up 
near  Kilo  by  a  syndicate  of  Australian  miners. 
The  country  is  of  a  granitic  and  gneissoid 
character  and  is  believed  to  possess  consider- 
able mineral  possibilities.  The  district  is  not 
a  healthy  one  and  the  transport  of  machinery 
and  stores  from  Entebbe  in  Uganda,  which  is 
connected  with  the  Mombasa- Port  Florence 
railway,  is  an  expensive  and  difficult  matter. 
Some  time  ago  the  geologist  of  the  East  Africa 
and  Uganda  Protectorates  reported  on  the 
area  lying  immediately  east  of  the  Congo 
State  frontier,  and  it  is  quite  likely  that  in 
the  near  future  when  lakes  Albert  and  Albert 
Edward  are  linked  with  the  Victoria  Nyanza 
and  the  Uganda  railway  this  area  will  attract 
much  attention.  Another  and  equally  remote 
portion  of  the  Congo  territory  where  extensive 
mineral  deposits  have  been  discovered  is  in  the 
Mweru  and  Bangweolo  lake  region.  A  group 
of  Belgian  financiers,  styled  the  Thys-Jadot 
Syndicate,  has  acquired  large  concessions  in 
this  locality,  and  these  have  been  found  to  con- 
tain copper-bearing  areas  similar  in  minerali- 
zation to  those  exploited  in  Katanga. 

In  northwestern  Rhodesia  there  are  several 
mineral-bearing  areas  north  of  the  Kafue  river. 
The  most  important  and  interesting  of  these 
are  the  lead-zinc  deposits  at  Broken  Hill,  375 
miles  north  of  the  Victoria  Falls,  the  Bwana 
M'Kubwa  copper  mine  on  the  Congo- Rhode- 
sian  border,  the  Kansanshi  copper  mine  of  the 
Tanganyika  Concessions  to  the  northwest  of 
Broken  Hill,  the  copper  mines  situated  in  the 
hook  of  the  Kafue  River,  and  the  coal  mea- 
sures of  the  Luano  Valley  to  the  southeast  of 
Broken  Hill. 

Broken  Hill,  2014  miles  from  Cape  Town, 
was  the  immediate  objective  of  the  Cape  - 
Congo  railway  after  the  bridging  of  the  Zam- 
besi at  the  Victoria  Falls.     There  exist  here 


SEPTEMBER,    1911 


215 


a  number  of  hillocks  or  kopjes  containing  large  during  the  last  three  years  small  parcels  of  it 

amounts  of  mixed  zinc  and  lead  ores.     The  have  been  sent  to  Europe  for  experimental 

continuity   of  these  deposits  to  a    moderate  purposes  only.  From  the  point  of  view  of  the 

depth   has  been   proved   by  boring  and  it  is  mineralogist  Broken  Hill  is  of  exceptional  in- 


CENTRAL    AFRICA. 


estimated  that  some  hundreds  of  thousands  of 
tons  of  ore  await  immediate  mining.  The  rail- 
way reached  Broken  Hill  five  years  ago  and 
small  shipments  of  calamine  were  then  de- 
spatched to  Europe.  The  quantity  of  '  free  ' 
ore  in  the  property,  however,  is  small,  and 
3—5 


terest,  containing  as  it  does  mixed  ores  of  lead 
and  zinc  sulphides  and  sulphates,  carbonates, 
silicates,  and  phosphates.  Here  are  found  the 
rare  hydrated  phosphates  of  zinc  known  as 
Tarbuttite  and  Hopeite.  While  the  remark- 
able variety  and  association  of  the   Broken 


216 


THE    MINING    MAGAZINE 


Hill  ores  are  of  exceptional  technical  interest, 
these  characteristics  have  proved  far  from 
satisfactory  to  shareholders.  For  long  the 
solution  of  the  metallurgical  problems  inciden- 
tal to  this  venture  have  remained  in  abeyance. 
About  the  middle  of  last  year  the  company 
was  reconstructed  and  at  the  same  time  a  sub- 
sidiary company  was  formed  to  deal  with  the 
complex  ores.  But  a  few  months  ago  when  I 
visited  the  property  the  mine  was  idle  and 
from  all  that  is  to  be  gathered  the  new  era 
predicted  in  the  prospectus  has  not  yet  begun. 

On  the  frontier  of  the  Congo  State  and 
northwestern  Rhodesia,  the  Northern  Copper 
Co.  possesses  the  Bwana  M'Kubwa  mine, 
famous  for  beautiful  specimens  of  malachite. 
Engineers  have  reported  that  the  quantity  of 
ore  exposed  at  80,000  tons  of  14%  ore,  and  in 
addition  a  large  quantity  of  lower  grade  stuff, 
yet  apart  from  shaft-sinking  little  work  is  being 
undertaken  at  present.  This  mine  is  a  sub- 
sidiary of  the  Rhodesia  Copper  Co.,  which  in 
turn  is  an  off-shoot  of  the  Northern  Copper 
Co,  In  this  locality,  too,  is  the  Roan  Ante- 
lope mine,  a  property  of  less  importance. 

In  the  hook  of  the  Kafue  river  there  are  a 
number  of  copper  properties  under  the  control 
of  the  Kafue  Copper  Development  Co.,  not- 
ably the  Silver  King,  Sable  Antelope,  Rhino, 
and  Hippo  mines.  These  are  situated  some 
distance  from  the  Kafue,  and  on  account  of 
transport  difficulties  and  also  because  of  the 
comparatively  low  grade  of  the  ore,  the  mines 
have  never  come  prominently  before  the  pub- 
lic. At  one  time  the  construction  of  a  branch 
line  from  the  Kafue  river  station  on  the  Beira 
&  Mashonaland  Northern  Extensions  Rail- 
way was  considered,  but  the  project  has  never 
materialized,  and  the  prospects  of  its  doing  so 
are  remote.  As  an  alternative  the  utilization 
of  some  of  the  navigable  stretches  of  the  river 
combined  with  a  porterage  system  along  the 
banks,  where  rapids  occur,  has  been  sug- 
gested ;  this  scheme  also  seems  to  have  fallen 
out  of  favour. 

The  only  other  mine  of  importance  in 
northwestern  Rhodesia  is  the  Kansanshi,  in 
which  the  Tanganyika  Concessions  is  largely 
interested.  Given  railway  communication, 
this  property  might  soon  enter  an  important 
productive  stage.  As  yet  no  such  scheme 
appears  to  have  been  mooted  and  the  pro- 
perty cannot  at  the  present  day  be  regarded  as 
an  asset  of  much  value.  A  little  gold  has 
been  found  near  Kasempa  in  banded  iron- 
stone, and  toward  the  end  of  last  year  a  com- 
pany was  formed  to  exploit  this  deposit. 
Northwest  Rhodesia,   unlike   southern   Rho- 


desia, appears  to  be   singularly   poor  in  the 
precious  metals. 

In  the  adjacent  territory  of  northeastern 
Rhodesia,  a  vast  and  practically  untravelled 
area  which  extends  to  Lake  Tanganyika, 
an  occurrence  of  gold  in  the  Luangwa  valley 
at  Sassare  has  been  worked  for  some  years 
in  a  small  way.  The  difficulty  of  transport 
in  connection  with  this  mine  has  proved 
enormous  ;  it  is  indeed  reported  that  it  took 
a  traction  engine  two  years  to  reach  the 
property  from  Tete.  Add  to  this  the  discon- 
certing fact  that  sleeping  sickness  is  sweep- 
ing down  the  valley,  and  it  will  be  apparent 
that  Sassare  is  not  a  venture  of  any  great 
promise.  Gold  occurs  here  in  basement 
schists  which  are  correlated  with  the  Swazi- 
land schists  of  the  Transvaal. 

About  160  miles  north  of  the  Zambesi,  in 
Portuguese  Northern  Zambesia,  some  ac- 
tivity has  been  displayed  of  recent  years  at 
Chifumbaze,  and  25  miles  farther  north,  at 
Missale,  on  the  borders  of  northeastern  Rho- 
desia, Nyasaland,  and  Portuguese  Zambesia, 
a  little  work  has  been  proceeding  on  an  auri- 
ferous quartz  lode  known  as  the  Chabuino. 
At  Chifumbaze  a  German  company  has  erec- 
ted, on  the  Maggie's  Luck  mine,  a  10-stamp 
battery  and  has  been  working  some  gold- 
bearing  quartz  leaders  in  a  granitic  matrix, 
but  the  results  to  date  do  not  indicate  a 
profitable  operation.  Four  miles  from  the 
Chifumbaze  administrative  post  there  is  an- 
other gold  -  bearing  proposition  known  as 
Muende  where  encouraging  assays  have  been 
obtained  in  a  well  defined  highly  pyritic  lode, 
which  has  been  opened  up  for  at  least  a  mile 
along  the  surface  and  by  means  of  several 
shafts.  The  lode  is  excessively  hard  and 
this  has  militated  greatly  against  develop- 
ment work.  Chifumbaze  is  evidently  the 
centre  of  a  mining  area  of  great  antiquity. 
On  many  of  the  granite  boulders  scattered 
along  the  flanks  of  the  mountain  ranges,  in- 
scriptions and  paintings  which  are  considered 
by  authorities  to  date  from  a  remote  past 
have  been  found,  and  there  are  also  extensive 
ancient  workings  in  the  vicinity.  The  Cha- 
buino mine  at  Missale  is  owned  by  a  Chinde 
syndicate  and  attempts  are  now  being  made 
to  float  a  company  with  a  substantial  working 
capital.  Another  mine  situated  about  80 
miles  north  of  Tete  is  the  Machinga,  where  a 
medium-grade  quartz  proposition  is  being  de- 
veloped. A  five  stamp-battery  has  recently 
been  erected  here  after  well  nigh  insuperable 
transport  difficulties  had  been  overcome. 

Coal    has    been  found   in  restricted  areas 


1 


SEPTEMBER,    1911 


217 


along  the  Zambesi.  Little  attention  has 
been  paid  to  the  development  of  this  asset  as 
yet  and  the  river-steamers  all  consume  wood 
as  fuel.  This  deforestation  is  undoubtedly 
exerting  a  bad  influence  on  the  rainfall.  Cop- 
per has  also  been  discovered  and  graphite 
occurs  in  Portuguese  Angonia.     Gold  is  found 


The  mineralized  kopje  of  the  Bhoilesia  Broken  Hill. 

in  Nyasaland  near  Fort  Johnston  and  at  a 
number  of  other  places  ;  it  is  distributed  over 
a  large  area  of  the  British  Central  African 
Protectorate,  but  apparently  in  unprofitable 
proportion.  Graphite  is  being  opened  up  in 
the  Angoniland  or  midwestern  part  of  the 
Protectorate  ;  it  is  reported  to  be  of  high- 
grade  quality  and  an  interest  has  been  ac- 
quired in  the  deposit  by  Lewis  &  Marks,  the 
South  African  financiers.  Mica  occurs  in 
Nyasaland  and  is  of  a  most  promismg  quality. 
It  is  found  notably  near  Fort  Johnston  at  the 
southern  end  of  Lake  Nyasa,  from  which 
place  considerable  quantities  have  already 
been  exported.  The  mica  industry  bids  fair 
to  become  an  important  commercial  factor  in 
the  future  development  of  Nyasaland.  This, 
however,  is  a  colony  that  can  never  take 
prominent  rank  among  the  important  com- 
mercial dominions  of  Africa  until  the  south- 
ern end  of  the  lake— the  trade  centre  of  the 
country — is  in  direct  railway  communication 
with  the  coast.  The  Shire  Highlands  Rail- 
way is  an  unfinished  transport  enterprise 
that  extends  from  Blantyre  to  Port  Herald, 
a  distance  of  114  miles.  Transport  in  the 
Nyasaland  Protectorate  has  in  the  past  de- 
pended largely  on  the  Shire  river,  which  flows 
out  of  Lake  Nyasa  and  enters  the  Zambesi 
near  Villa  Bocage  in  Portuguese  East  Africa. 
It  is  a  well  known  geographical  fact  that  of 
recent  years  the  level  of  the  waters  in  Nyasa 
has  been  declining  and  consequently  the  Shire 


before  the  rains  have  fallen  has  proved  an 
unsatisfactory  water-way.  Hence  the  trade 
of  the  Protectorate  has  been  greatly  ham- 
pered, and  it  is  recognized  that  no  real  assur- 
ance with  regard  to  transport  will  be  possible 
until  the  lake  and  the  Indian  Ocean  are 
linked  by  a  dependable  means  of  communica- 
tion. Between  the  coast  of  Portuguese  East 
Africa  and  Lake  Nyasa  there  are  indications 
of  mineral  wealth.  One  or  two  expeditions 
have  of  recent  years  penetrated  into  this  hin- 
terland, which  is  unhealthy,  little  known,  and 
peopled  by  natives  who  are  not  well  disposed 
toward  Europeans.  One  expedition  was  des- 
patched by  the  Rhodesia  Exploration  &  De- 
velopment Co.  during  the  last  dry  season  to 
Ribawe  and  the  Bwa  Bwa  river,  but  the 
results  secured  were  of  an  inconclusive  nature. 
One  or  two  of  the  members  of  the  expedition 
died,  and  the  mission  generally  was  a  failure. 
In  German  East  Africa,  gold  has  been  dis- 


Bridge  over  the  Kafue. 

covered  in  several  localities,  notably  in  the 
vicinity  of  Mwanza,  a  port  on  the  southern 
end  of  the  V^ictoria  Nyanza.  The  precious 
metal  occurs  here  in  granite  and  recently 
some  high  assays  have  been  reported.  It  is 
understood  that  a  company  is  about  to  be 
formed  in  London  to  exploit  the  Mwanza 
gold  mining  area,  which  is  now  being  exam- 
ined for  a  report. 

British  East  Africa  it  apparently  a  colony 
of  little  or  no  mineral  possibilities  apart  from 


218 


THE    MINING    MAGAZINE 


soda.  The  recently  floated  Magadi  Soda  Co. 
has  a  scheme  of  a  highly  ambitious  nature 
under  consideration  in  connection  with  the 
famous  Magadi  deposit,  a  scheme  that  in- 
cludes the  construction  of  a  branch  line  from 
the  lake  to  the  trunk  system  of  the  Uganda 
Railway  and  the  improvement  of  loading 
arrangements  at  Kilindini,  the  port  of  the 
country.  The  deposit  of  the  Magadi  lake  is 
a  notable  occurrence,  fresh  soda  crystals  be- 
ing continually  formed.  Having  regard  to 
the  strong  and  influential  auspices  under  which 
the  project  has  been  launched  it  appears  highly 
probable  that  the  export  of  soda  w^ill  become 
one  of  the  principal  industries  of  a  colony 
which  hitherto  has  seemed  to  be  best  fitted 
for  the  stock  farmer,  the  rubber  planter,  and 
the  big-game  hunter. 

A  little  copper,  in  the  form  of  malachite, 
has  been  found  in  the  Protectorate  near  Tsavo 
(renowned  for  lions)  and  indications  of  coal 
have  been  discovered  at  several  points,  but 
generally  speaking  the  East  African  Protec- 
torate is  not  a  region  that  offers  attractions  to 
the  financier  or  the  engineer. 

The  further  development  of  the  various 
mineral  deposits  of  Central  Africa  is  obvi- 
ously dependent  upon  the  general  policy  of 
the  controlling  powers  with  regard  to  rail- 
ways. There  are  many  mineral  fields  where 
the  advent  of  a  cheaper  and  more  efficient 
means  of  transport  would  stimulate  the  areas 
in  question  into  production,  whereas  today 
the  great  bulk  of  these  are  of  potential  impor- 
tance only.  Equally  vital  are  questions  re- 
lative to  native  labour  and  the  scientific  con- 
quest of  tropical  diseases,  such  as  malarial 
fever,  blackwater  fever,  and  sleeping  sickness. 
The  onward  march  of  civilization  and  the  in- 
creasing demands  of  the  modern  world  for 
metals  and  profitable  fields  for  the  investment 
of  capital  will  in  the  fulness  of  time  make 
Central  Africa,  like  South  Africa,  a  vast  and 
productive  mineral  field.  These  develop- 
ments cannot  progress  at  any  noteworthy 
rate  at  present ;  and  it  may  safely  be  as- 
sumed that  many  years  will  elapse  before  the 
mineral  deposits  of  the  heart  of  the  Last 
Continent  will  attract  anything  like  the  atten- 
tion that  has  been  accorded  to  the  Southern 
and  Western  regions. 


Transvaal  Diamonds. — Official  returns 
have  been  issued  of  the  production  of  diamonds 
in  the  Transvaal  for  the  first  half  of  1911.  In 
giving  the  figures  we  would  make  the  prefa- 
tory reminder  that  the  chief  producer  in  the 
Transvaal  is  the  Premier  mine  ;  and  that  the 
other  great  producers,  the  De  Beers  and  the 
Jagersfontein,  are  in  the  Cape  Colony  and 
Orange  Free  State  respectively.  The  num- 
ber of  loads  washed  during  the  half-year  v/as 
4,107,733,  the  yield  852,719  carats,  and  the 
value  ^659,968,  as  compared  with  4,362,107 
loads,  942,289  carats,  and  ^^607,024  during 
the  second  half  of  1910.  It  will  be  seen, 
therefore,  that  though  the  output  was  smaller, 
the  prices  received  by  producers  from  the 
selling  syndicate  have  advanced.  The  follow- 
ing table  gives  figures  relating  to  the  output 
during  the  last  10  statistical  years  commencing 
with  July  : 

\'alue 
Year  Carats  £ 

1902-3   33,572  46,358 

1903-4  497,917  625,720 

1904-5   995,002  1,198,530 

1905-6   758,406  968,229 

1906-7  1,545,336  2,203,511 

1907-8  2,184,490  1,879,551 

1908-9  1,929,491  1,295,296 

1909-10 2,098,528  1,317,479 

1910-11 1,795,008  1,266,992 


Oil  in  Mexico. — The  West  Coast  Oil 
Co.,  in  which  English  capital  is  largely  con- 
cerned, and  which  hopes  to  develop  extensive 
oil  supplies  in  the  West  of  Mexico,  has 
commenced  drilling  in  Northern  Sonora.  The 
scene  of  operations  is  near  Mascarehas. 


Coal  in  Ireland. — A  scheme  is  on  foot  to 
work  the  coalfield  in  Kilkenny  and  Queen's 
counties  in  the  southeast  of  Ireland.  Par- 
liamentary powers  have  been  obtained  for  the 
purpose  of  constructing  a  railway  line  from 
Athy  to  Kilkenny,  that  will  pass  through  the 
district.  For  some  time  the  deposit  has  been 
worked  on  a  small  scale,  about  40  tons  being 
raised  per  day.  It  is  intended  to  increase  the 
output  to  400  tons  per  day  when  railway  com- 
munication is  secured.  The  promoters  assert 
that  100  million  tons  of  steam  coal  are  as- 
sured, but  there  are  good  reasons  for  doubting 
their  claim  both  as  regards  extent  and  quality. 
As  in  many  other  ways,  Ireland  has  been  un- 
lucky in  respect  of  her  coal  measures.  The 
central  part  of  the  country  is  a  vast  plain 
with  mountain  limestone  as  the  basal  rock  and 
covered  with  drift  and  peat.  At  one  time  the 
limestone  was  covered  with  coal  measures, 
but  nearly  the  whole  has  been  swept  away, 
leaving  only  a  few  isolated  patches  here  and 
there,  that  mentioned  and  one  near  the 
junction  of  Cork,  Limerick,  and  Kerry  coun- 
ties being  the  largest.  There  are  also  smaller 
patches  farther  north  in  Meath,  Tyrone,  and 
Leitrim. 


SEPTEMBER,    1911 


219 


DISCUSSION 

Our  readers  are  invited  to  criticise  anything  appearing  in  this 
magazine  and  to  discuss  other  subjects  of  general  technical 
interest. 

Percentage  of  Recovery. 

The  Editor  : 

Sir — Mr.  C.  W.  Wright,  in  the  July  number 
of  your  magazine,  gives  a  valuable  addition  to 
the  mathematics  of  the  calculation  of  percen- 
tage of  recovery.  When  my  first  suggestion 
was  published  some  months  ago  I  was  under 
the  impression  the  idea  was  new,  but  since 
then  I  have  been  made  aware  that  several 
dozen  engineers  '  knew  all  about  it  a  long 
time  ago."  There  was,  however,  one  publica- 
tion— of  which  I  was  entirely  unaware  at  the 
time  I  wrote  my  article — that  I  should  men- 
tion :  Dr.  Rudolf  Gahl,  in  the  April  1909 
number  of  the  Western  Chemist  and  Metal- 
lurgist, published  a  most  excellent  article  on 
the  calculations  of  percentages  of  recovery,  in 
which  article  he  completely  anticipates  all  my 
ideas,  and  sets  forth  in  a  very  able  manner 
several  other  valuable  formulas  for  the  use  of 
engineers.  Though  perhaps  unkind  to  say  it 
I  feel  it  nevertheless  is  true  that  the  reason  of 
the  oversight  was  that  Dr.  Gahl's  article  was 
published  in  a  paper  of  so  little  circulation 
that  the  average  engineer  had  no  chance  of 
seeing  it.  Had  Dr.  Gahl  published  his  article 
elsewhere  than  in  a  backwoods '  magazine  I 
would  not  have  '  infringed  "  his  "  invention." 
Theodore  J.  Hoover. 

London,  July  14. 

Values. 

The  Editor : 

Sir— In  an  editorial  in  your  April  number 
I  read  with  interest  your  criticism  of  the  use 
of  the  word  '  value  '  in  mine  reports,  and  al- 
though an  enthusiastic  supporter  of  your  cam- 
paign against  illiterate  reports  and  loosely 
worded  technical  articles,  I  venture  to  think 
that  you  have  been  hyper-critical,  if  not  in 
error,  in  your  complaint  of  Mr.  H.  A.  Piper's 
use  of  the  term  in  question. 

It  would  seem  from  your  article  that  you 
consider  '  value  '  only  refers  to  £ .  s.  d.,  but 
surely  the  value  of  many  things  is  not  mea- 
sured by  money  ;  for  instance,  the  value  of  ;*: 
and  J  in  a  quadratic  equation  is  not  always 
found  in  pounds  sterling.  Mr.  Piper's  use  of 
the  term  is  merely  a  contraction  of  assay- 
value,  and  the  measure  of  an  assay-value  is 
expressed  in  dwt.or  percentage  ;  but  even  sup- 
posing value '  is  not  a  contraction  of  assay- 
value,  I  disagree  that  unprofitable  ore  should 
be  called  '  valueless.' 


Would  you,  Mr.  Editor,  in  reporting  that 
the  s.s.  Unfortunate  had  foundered  in  mid- 
Atlantic  with  specie  on  board,  state  :  There  is 
a  certain  amount '  of  gold  of  no  value  at  the 
bottom  of  the  Atlantic  "  ?  Would  you  not 
prefer  to  write  :  "There  is  gold  to  the  value 
of  ^1,000,000  at  the  bottom  of  the  ocean,  but 
we  fear  that  its  recovery  will  be  an  unprofitable 
enterprise." 

There  are  doubtless  methods  and  processes 
of  the  future  that  will  turn  mines  at  present 
unprofitable  into  profitable  concerns,  but  obvi- 
ously there  is  nothing  except  the  philosopher's 
stone  that  will  turn  valueless  quartz  into  valu- 
able gold.  I  suppose  all  engineers  agree  that 
the  net  profit  on  ore  developed  is  the  most 
important  point  of  a  mine  report,  but  why 
deprive  interested  shareholders  of  information 
concerning  the  '  values  '  of  an  unpromising 
block  of  ground. 

William  R.  Rumbold. 

Northern  Nigeria,  June  3. 

[Mr.  Rumbold's  protest  is  welcome,  even  if 
we  cannot  accept  his  view  of  the  case.  Un- 
doubtedly we  are  in  danger,  like  other  enthusi- 
astic reformers, of  being  hyper-criticalattimes. 
Is  it  not  true,  however,  that  '  value '  as  used 
in  commercial  affairs,  especially  in  connection 
with  the  exploitation  of  mineral  resources,  does 
refer  to  measure  in  units  of  money  ?  The  miner 
does  not  look  at  his  ore  with  the  eye  of  a 
philosopher,  otherwise  indeed  he  might  read 
into  '  value  '  a  hundred  meanings  of  a  most 
allusive  kind.  For  instance,  the  value  of  a 
discovery  of  gold  ore  in  a  new  region  is  not 
only  its  gift  of  wealth  to  an  individual  pros- 
pector but  the  spread  of  modern  civilization 
into  a  new  corner  of  the  earth.  Even  a  find 
unprofitable  in  terms  of  money  may  prove  of 
the  utmost  beneficence  by  stimulating  explor- 
ation and  inducing  immigration  in  a  country 
capable  of  development  inbranchesof  industry 
other  than  mining.  In  regard  to  the  use  of 
'  value '  as  a  synonym  for  '  assay-value,'  we 
have  already,  in  the  leader  criticized,  drawn 
attention  to  the  confusion  likely  to  arise,  share- 
holders and  the  public  generally  assuming  that 
it  means  '  profit.'  The  '  assay-value '  of  an 
ore  is  its  gross  value,  according  to  the  market 
price  of  the  metals  contained,  but  its  '  value  ' 
is  the  gross  value  less  the  total  cost  of  extrac- 
tion, in  other  words,  the  net  return  to  the  pro- 
prietors. An  ore  containing  1*9  dwt.  gold,  with 
traces  of  copper,  in  Rhodesia  may  be  said  to 
afford  indications  useful  to  a  prospector  but  it 
cannot  be  described  as  having  any  commercial 
value  in  the  year  1911.  Possibly  in  2011,  or 
even  sooner,  such  ore  will  become  a  source  of 


220 


THE    MINING    MAGAZINE 


wealth  to  the  enterprising  operator.  In  the 
meantime  we  try  to  give  precision  to  words  by 
hmiting  their  meaning  so  that,  for  example, 
an  ore  is  said  to  have  value  when  it  yields 
a  profit  in  this  day  and  generation,  not  post 
paulo  futiirum.  The  ocean  contains  gold 
values  in  the  Pickwickian  sense  of  Messrs. 
Piper  and  Rumbold,  but  it  has  no  value  just 
now  as  a  gold  mine.  In  the  Greek  Kalends 
we  may  find  it  more  profitable  to  work  at  sea 
than  on  land,  but  not  in  the  palpitating  pre- 
sent. Those  who  find  that  they  can  express 
themselves  explicitly  by  using  '  value '  and 
'  values '  will  continue  to  do  so,  but  we  hope 
that  they  will  reconsider  the  matter  anew. — 
Editor.] 

Official  Valuation  of  Shares. 

The  Editor : 

Sir — From  your  columns  I  gather  that  you 
and  many  of  your  contributors  regard  precious 
metal  mining  as  a  legitimate  business  and  that 
you  consider  mining  engineers  as  honoured 
members  of  society.  My  own  observations 
are  at  variance  with  these  conclusions,  for  I 
find  that  precious  metal  mining  is  regarded  by 
many  financiers  as  less  dignified  than  horse- 
racing,  and  that  mining  engineers  are  given  a 
lower  social  rating  than  horse-trainers. 

The  management  of  the  precious  -  metal 
mines  is  largely  entrusted  to  graduates  from 
technical  schools  ;  these,  when  beginning  the 
practice  of  their  profession,  are  men  of  high 
ideals.  Hence,  it  would  seem  to  follow  that 
precious-metal  mining  should  be  honestly  con- 
ducted, and  that  mining  shares  should  be  re- 
garded with  favour  by  conservative  financiers. 
But  the  actual  state  of  the  case  is  that  the 
purchaser  of  mining  shares  is  regarded  as  a 
gambler  and  the  industry  is  thereby  discredited. 
To  a  high-minded  engineer  the  odium  wrongly 
attached  to  the  business  is  galling.  That  it  is 
galling  is  shown  by  the  active  manner  in  which 
mining  finance  is  being  discussed  in  the  tech- 
nical Press,  notably  in  your  columns. 

I  do  not  consider  that  this  disrepute  need 
be  permanent  and  I  propose  to  point  out  a 
powerful  means  of  bringing  mining  into  better 
repute.  My  proposal  is  that  shareholders  in 
all  precious-metal  mines  be  furnished  with  an 
official  valuation  of  their  shares  at  least  once 
a  year,  or  oftener,  if  necessary. 

Mr.  M.  H.  Burnham  (in  your  issue  of  July) 
has  recently  studied  this  question  and  has  sug- 
gested that  fuller  information  be  furnished  to 
the  shareholders  of  mining  companies.  His 
suggestion  is  admirable,  but  it  does  not  go  far 
enough.     Even  if  the  information  he  asks  is 


given,  the  position  of  the  ordinary  buyer  of 
mining  shares  is  but  little  improved,  for  it  is 
impossible  for  the  ordinary  mind  properly  to 
interpret  the  mass  of  statistics  included  in  a 
complete  mining  report.  The  prospective 
buyer  or  shareholder  asks  :  '  What  are  the 
shares  worth?"  Every  annual  report  should 
answer  this  question  explicitly.  The  filling 
up  of  the  following  form  would  give  all  the 
essentials  : 

A  fair  valuation  of  the  shares  of  the  Hypo- 
thetical Mining  Company  on  June  30,  1911,  is: 

Preference  shares £ 

Ordinary  shares £ 

This  value  is  deduced  from  : 

Present  value  of  the  plant.... ^ 

Value  of  ore  developed £ 

Value  of  probable  ore £ 

Value  of  other  assets ;^ 

Total  value  of  property ^ 

Number  of  preference  shares..^ 

Number  of  ordinary  shares...^ 

\'alue  per  share £ 

This  valuation  should  be  made  by  the  man- 
ager of  the  company,  and  a  full  explanation 
should  be  given  as  to  how  it  is  obtained.  In 
other  words,  instead  of  having  a  hodge-podge 
of  statistics,  which  not  one  man  in  fifty  can 
interpret  correctly,  I  would  give  the  share- 
holder the  final  opinion  of  the  management  as 
to  the  value  of  his  shares. 

I  do  not  contend  that  this  valuation  will  be 
absolutely  accurate,  but  it  will  be  definite  and 
will  represent  the  best  judgment  of  experts 
most  familiar  with  the  property.  The  chief 
merit  of  the  valuation  is  that  it  tends  toward 
openness  and  straightforwardness ;  it  works 
against  crookedness  and  concealment.  When 
generally  adopted  it  will  be  a  great  safeguard 
against  the  wiles  of  the  predatory  promoter, 
both  for  the  engineer  and  the  public. 

It  does  not  follow  that  the  market-price  of 
the  shares  will  be  identical  with  the  valuation, 
but  there  will  certainly  be  a  close  connection 
between  the  two  ;  and  the  official  valuation 
will  surely  tend  to  prevent  such  sensational 
collapses  as  have  been  lately  seen  in  Waihi, 
Golden  Horse-Shoe,  and  (Editor,  please  men- 
tion some  instances  of  sudden  falls  in  market- 
price).  [It  is  not  necessary,  each  reader  can 
do  so  for  himself. — Editor.] 

I  feel  quite  certain  that  if  a  system  of 
managerial  valuation  of  mining  shares  is  put 
into  practice  it  will  greatly  benefit  all  honestly 
managed  mining  companies  ;  and  all  persons 
interested  will  wonder  why  business  was  done 
without  it. 


SEPTEMBER,    1911 


221 


Possibly  some  of  your  readers  may  cavil  at 
my  calling  the  buying  of  precious-metal  min- 
ing shares  "  gambling  "  and  may  retort  by 
remarking  that  "  Everything  is  a  gamble." 
In  the  misty  domain  of  metaphysics  this  dic- 
tum may  be  true,  but  in  the  actual  world  of 
finance  it  is  easy  enough  to  draw  a  sharp  dis- 
tinction between  investing  and  gambling. 

A  concrete  instance  may  make  my  state- 
ment plainer  :  Suppose  the  case  of  a  young 
heir  who  has  just  received  his  fortune  and 
finds  that  it  is — with  mistaken  wisdom — in- 
vested in  British  trustee  stocks  bringing  3*% 
income.  If  our  young  friend  wishes  to  in- 
crease his  income  and  consults  a  financier 
regularly  engaged  in  the  prudent  investment 
of  funds,  say,  the  manager  of  the  securities 
department  of  one  of  the  London  joint-stock 
banks,  and  says  to  him  :  "  I  am  thinking  of 
selling  out  my  trustee  securities  and  buying 
some  better -paying  bonds  such  as  Chilian 
Govt.  5%  ;  Rio  de  Janeiro  Trams  First  Mort- 
gage ;  Antofagasta  &  Bolivia  Railway  bonds  ; 
Southern  Pacific  convertible  4's.,"  nearly 
every  conservative  financier  in  London  will 
say :  "  I  think  on  the  whole  that  you  are 
making  a  good  investment."  But  if  the  same 
young  heir  were  to  say  :  "  I  propose  to  sell 
my  trustee  stocks  and  put  the  money  in  the 
following  gold-mines."  (Let  the  reader  fill 
out  the  list  to  his  own  satisfaction).  The 
equally  certain  reply  would  be  :  "I  cannot 
advise  you  to  make  the  change  ;  you  had  bet- 
ter stick  to  the  securities  that  you  have  and 
not  begin  gambling." 

Humanly  speaking,  the  capital  invested  in 
the  sound  securities  will  be  intact  ten  years 
hence,  while  a  large  portion  of  the  money 
used  in  buying  mining  shares  will  be  lost.  On 
the  other  hand,  there  is  no  likelihood  of  the 
sound  securities  advancing  greatly  in  price 
while  there  are  great  chances  of  gain  from  the 
advance  in  price  of  the  mining  shares. 

Everyone  familiar  with  the  subject  can  re- 
call mining  shares  that  have  doubled  or  trebled 
in  price  within  a  year,  and  greater  gains  are 
not  uncommon,  for  instance  :  the  shares  of  the 
Mohawk  mine  in  Nevada  advanced  from  20 
cents  to  $20  within  a  year.  Equally  familiar 
are  the  sudden  collapses  in  the  price  of  mining 
shares  :  witness  the  recent  tumble  in  the  price 
of  Waihi.  Thus  the  buying  of  precious-metal 
mining  shares  brings  prizes  and  blanks,  and 
dealing  in  them  is  practically  a  lottery. 

The  gambling  spirit  is  inherent  in  human 
nature  and  men  will  always  pay  more  for  a 
gambling  chance  than  its  strict  mathematical 
value  as  calculated  by  the  theory  of  probabili- 


ties :  consequently  the  market-price  of  mining 
shares,  as  a  whole,  will  always  exceed  their 
real  value.  Thus,  from  my  point  of  view,  the 
case  of  the  buyer  of  mining  shares  is  always 
desperate,  and  to  handicap  him  further  by  in- 
complete and  misleading  reports  is  an  out- 
rage. He  should  be  put  in  possession  of  all 
the  essential  facts  relating  to  the  company  in 
which  he  has  an  interest  and  the  final  deduc- 
tion from  these  facts — that  is,  the  valuation 
of  the  shares — should  be  made  for  him  by  his 
servants,  the  directors  and  manager  of  the 
company,  who  alone  have  all  the  data.  And 
it  is  because  I  want  shareholders  to  be  fairly 
treated,  and  to  be  in  a  position  to  act  intelli- 
gently, that  I  advocate  this  managerial  valua- 
tion of  mining  shares  in  the  annual  reports  of 
companies. 

The  giving  of  detailed  information  as  to  ore 
reserves,  costs,  and  other  factors  controlling 
the  values  of  the  shares  is  becoming  more 
common  ;  some  of  the  best  reports  furnish 
almost  all  of  the  information  needed,  but  even 
these  exceptional  reports  would  be  greatly  en- 
hanced in  utility  if  they  contained  a  direct 
valuation  of  the  shares. 

Such  full  reports  are,  however,  in  a  mino- 
rity ;  the  great  majority  of  mining  reports  do 
not  give  enough  information  to  allow  of  a  cor- 
rect valuation  ;  or,  if  the  information  is  con- 
tained in  the  report,  it  is  given  in  a  confused 
manner  and  thus  rendered  practically  useless. 
To  show  more  plainly  what  I  mean  I  select 
at  random  the  last  report  I  have  received — 
that  of  the  Prestea  Block  A — for  the  year 
ending  December  31,  1910.  This  report  is 
unusually  and  commendably  full,  and  is  par- 
ticularly complete  because  it  contains  a  map 
of  the  ore  reserves.  But  the  report  contains 
no  valuation  of  the  shares  and  does  not  give 
enough  information  to  enable  a  reader  to  value 
them.  I  notice  that,  in  an  editorial  in  your 
July  issue,  you  attempt  to  value  these  shares 
and,  with  all  due  deference  to  your  special 
knowledge  of  mining  costs  and  accounts,  I 
think  your  valuation  is  incorrect.  And,  cer- 
tainly, if  you,  with  your  great  experience  are 
led  into  error  an  ordinary  shareholder  would 
be  utterly  unable  to  approximate  the  value. 
Your  error  in  the  estimate  of  the  value  of 
these  shares  arises  from  an  assumption  that 
the  market-value  of  the  property  is  ;^1, 275,000' 
at  the  time  it  will  be  paying  ;^250,000  an- 
nually. This  market  value  is  based  on  850,000' 
shares  at  30s.  per  share,  the  present  quota- 
tion, but  it  is  stated  in  the  report  that  at  least 
;^200,000  more  capital  will  be  required  to 
complete  the  plant  ;  therefore  at  the  time  the 


222 


THE    MINING    MAGAZINE 


mine  is  earning  the  ^250,000  annually — if 
there  is  no  decline  in  the  market  price — the 
total  capital  will  be  at  least  iTl, 500,000  and 
the  profit  earned  will  be  only  16f%,  instead  of 
the  20%  you  make  it.  However,  I  am  not  at 
all  interested  in  getting  at  the  exact  valuation 
of  these  shares,  but  am  only  interested  in 
pointing  out  the  deficiencies  in  the  report. 
And  whether  you  are  right  or  not  on  this 
point  is  not  of  any  importance ;  the  discrep- 
ancy between  your  ideas  and  mine  only  shows 
how  essential  it  is  that  the  calculations  as  to 
the  value  of  the  shares  should  be  carried  out 
by  the  manager  of  the  company,  who  alone  is 
fully  conversant  with  all  the  data  required  for 
a  trustworthy  appraisal. 

In  the  case  of  the  Prestea  the  most  clever 
engineer  would  find  it  impossible  to  value  the 
shares  by  means  of  the  annual  report,  for  no 
estimate  of  the  probable  extraction  or  of  the 
probable  working  cost  is  explicitly  given.  I 
do  not  think  it  worth  while  to  go  further  into 
this  matter,  and  will  only  say  that  the  Prestea 
report  is  a  great  improvement  on  most  of  the 
mining  reports  that  I  read. 

There  is  no  reason  why  this  valuation  of 
shares  should  be  confined  to  mining  com- 
panies, and  I  believe  it  would  be  a  valuable 
feature  of  all  annual  company-reports  without 
reference  to  the  business  engaged  in.  I  re- 
commend the  subject  to  your  readers  for  dis- 
cussion and  suggest  that  the  Institution  of 
Mining  &  Metallurgy  might  well  insist  that 
its  standard  annual  mining  report  should  con- 
tain a  managerial  valuation  of  the  shares. 

Speculator. 

London,  August  20. 

Prospecting  in  the  North. 

The  Editor : 

Sir — I  have  read  Mr.  Winchell's  letter  in 
your  May  issue,  in  which  he  disavows  any  in- 
tention, in  his  article  on  '  Prospecting  in  the 
North,'  of  hitting  at  Canada — he  wasn't  think- 
ing of  her  at  all.  I  cheerfully  accept  this 
disclaimer.  If  he  had  gone  further  and  said 
there  were  other  things  he  had  overlooked,  I 
should  still  have  accepted  it.  I  merely  men- 
tioned Canada  to  account  for  my  temerity  in 
openly  questioning  the  conclusions  of  a  re- 
cognized authority  on  ore  deposits. 

Respecting  his  exception  to  my  use  of  the 
term  '  hydrosphere,'  it  of  course  is  not  a 
synonym  for  the  zones  of  rock  decay  and 
secondary  enrichment,  but  the  relationship 
that  exists  between  these  and  the  zone  in 
which  surface  water  "  permeates  the  pores 
and   fissures   of  the  outer  part   of   the   solid 


earth  "  or  "  exists  as  such  in  the  interstices 
of  the  lithosphere  "  seemed  to  me  so  obvious 
that,  lacking  a  strictly  applicable  technical 
term,  I  concluded  to  imitate  the  great  writers 
and  indulge  for  a  moment  in  metonymy.  Of 
course  the  proper  procedure  in  technical  liter- 
ature, when  one  cannot  recall  a  precise  tech- 
nical term,  would  be  to  invent  a  new  one.  I 
might  have  called  the  zones  of  rock  decay 
and  secondary  enrichment  the  '  minersphere.' 
It  would  naturally  be  limited  to  the  Temper- 
ate zone,  the  Boreal  or  Arctic  zone  constitut- 
ing merely  the  '  prospectorsphere.'  But  that 
wouldn't  have  settled  all  differences,  for  Mr. 
Winchell  would  still  have  insisted  that  the 
Temperate  zone  did  not  extend  into  the  gla- 
ciated belt,  while  I  should  ha\'e  quoted  dic- 
tionaries and  elementary  physical  geographies 
to  prove  that  properly  and  actually  it  em- 
braces most  of  the  glaciated  belt,  and,  in 
places,  districts  quite  beyond  the  northern 
edge  of  this  belt. 

He  considers  a  reference  to  dikes  irrelevant. 
But  it  was  introduced  in  opposition  to  his 
statement  that  in  the  rocks  in  the  glaciated 
zone  "  fissures  and  crevasses  are  rare  "  ;  where 
recent  dikes  are  so  numerous,  fissures  cannot 
have  been  rare. 

Mr.    Winchell    in    his    article   described  a 
limited  district  in  some  detail,  a  district  just 
emerging  from   glacial   conditions,   many    of 
which   still   obtain.      A   considerable  part   is 
still  under  ice.     The  exposed  glaciated  rocks 
have   just    come    into  contact   with   ihe   air. 
Erosion  under  these  conditions  is  excessive, 
decomposition  relatively   slight.       He   states 
that  the  description  "  holds  good  for  a  large 
portion  of  the  globe  in   northern   latitudes." 
With  this  I  cannot  agree.      It  holds  good  only 
for  those  areas  that  still  carry  glaciers,  or  from 
which  they  have  just  disappeared.     Elsewhere 
decomposition  is  relatively  important  and  ero- 
sion relatively  slight.      Consequently,  "  if  we 
contrast  the  situation  just  described  with  the 
conditions  farther  south  "  and  "  at  once  begin 
to  appreciate  a  few   of  the   reasons  why   so 
large  a  proportion  of  our  rich  mines  are  found 
south    of   the    border   of  the    former  glacial 
mantle,"  I  think  we  shall  be  liable  to  be  found 
in   error.     One   who  takes   this   appreciative 
position  surely  is  assuming  that  in  the  gla- 
ciated belt  glacial  conditions  have  always  ex- 
isted.     If  they  haven't,  rock  decay  and  secon- 
dary  enrichment  have  taken   place.      In   the 
Klondyke,  which,  we  shall  both  agree,  is  some- 
what boreal,  the  gold-bearing  White  Channel 
gravels  are  so  decomposed  that  even  magne- 
tite is  scarcely  to  be  found,  and  nothingremains 


SEPTEMBER,    1911 


223 


but  quartz  and  sericite.  It  is  difficult  any- 
where to  find  more  striking  examples  of  rock 
decay  than  in  this  boreal  region.  If  rock  de- 
cay has  been  important  in  pre-glacial  times, 
which  is  shown  to  be  the  case  in  the  Klon- 
dyke,  then  glaciation,  which  has  removed, 
except  locally,  little  but  the  decomposed  sur- 
face of  the  rock,  must  have  left,  except  lo- 
cally, the  enriched  sulphide  zones  of  veins. 
That  the  glacier  cannot  have  removed  much 
of  the  'live'  rock  is  proved  by  calculations 
of  the  amount  of  glacial  drift,  obtained  from 
the  glaciated  belt.  But  it  is  unnecessary  to 
build  up  an  argument  to  show  that  the  en- 
riched sulphide  zones  must,  in  many  cases  at 
least,  remain.  One  can  go  to  the  mines  to 
see  them  ;  there  they  are. 

I  do  not  see  the  grounds  for  his  implication 
that  those  in  glaciated  districts  fail  to  realize 
the  importance  of  secondary  enrichment.  As 
a  matter  of  fact  it  was  recognized  here  before 
the  papers  of  Emmons,  Weed,  and  others,  on 
the  subject,  filtered  into  darkest  Canada.  I 
did  not  minimize  its  importance  ;  my  argu- 
ment was  simply  that  even  if  it  were  admit- 
ted, which  I  certainly  did  not  admit,  that  no 
secondary  enrichment  was  to  be  found  in  the 
glaciated  belt,  in  the  face  of  the  discoveries 
in  the  prospected  fringe  of  this  belt,  one  was 
scarcely  justified  in  a  sweeping  generalization 
that  rich  mines  were  rare.  He  does  not  al- 
low secondary  enrichment  the  importance  I 
should  like,  or  was  contending  for. 

This  explanation  may  account  for  my  men- 
tioning classes  of  deposits  which  he  expressly 
excluded ;  though  why,  in  the  light  of  the 
views  of  the  Lake  Superior  geologists  con- 
cerning the  origin  of  the  iron  deposits  he 
should  so  exclude  them  or  why  loose  super- 
ficial gold  placers  should  prove  too  hard  a  nut 
for  a  glacier  that  was  sweeping  off  the  entire 
enriched  sulphide  zone,  is  not  obvious.  It 
will  not  do  to  say  that  gold  placers  do  not  re- 
quire decomposition  for  their  formation,  for 
in  regions  of  dominant  erosion  they  are  rela- 
tively rarer  than  rich  lodes,  and  the  richness 
of  a  placer  seems  to  bear  quite  as  intimate  a 
relation  to  the  extent  of  decomposition  as 
does  that  of  a  vein. 

I  confess  to  a  degree  of  prejudice  in  favour 
of  the  country  I  know  best.  I  doubt  if  my 
friend,  Mr.  Winchell,  is  wholly  free  from  the 
same  weakness ;  nor  is  the  prospector  who 
turns  down  the  new  camp  because  he  fails  to 
recognize  in  it  the  limestone  that,  in  his  old 
stamping  ground,  he  learned  to  love. 

R.  W.  Brock. 

Ottawa,  August  11. 


Critical  Moisture  in  Tube-Mill  Feed. 

The  Editor  : 

Sir — Replying  to  Mr.  W.  R.  Bowling's 
letter  of  May  15,  I  am  obliged  to  him  for 
pointing  out  that  there  is  much  more  water 
present  in  a  40%  pulp  than  is  required  to  fill 
the  voids,  and  consequently  for  correcting  any 
misapprehension  in  this  regard. 

Evidently  Mr.  Dowling  has  little  faith  in 
the  existence  of  a  critical  moisture,  since  he 
asks  us  to  believe  that  with  feeds  of  under  200 
tons  per  day,  a  27%  pulp  is  more  efficient  than 
a  more  diluted  pulp.  On  the  other  hand,  Mr. 
Neal  offers  satisfactory  data  for  believing  that 
with  a  feed  of  125  tons  per  day,  which  is  well 
under  Mr.  Bowling's  maximum  figure,  a  39% 
pulp  is  most  favourable  for  maximum  grinding, 
and  Mr.  Ball's  experiments  point  also  to  the 
existence  of  a  critical  moisture  almost  identical 
with  Mr.  Neal's. 

If  there  is  a  critical  moisture  there  ought 
to  be  a  reason  for  it  and  my  letter  was  written 
in  the  hope  that  additional  information  would 
be  forthcoming.  Under  the  circumstances,  I 
think  we  may  fairly  ask  Mr.  Bowling  to  offer 
as  satisfactory  a  series  of  experiments  in  sup- 
port of  his  statement  about  a  27%  pulp  as  Mr. 
Neal  offers  in  support  of  a  39%  pulp.  I  must 
frankly  admit,  in  the  light  of  Mr.  Bowling's 
remarks,  that  the  explanation  of  a  critical 
moisture  presents  difficulties  and  that  more 
data  will  be  required  to  reach  a  satisfactory 
conclusion.  Possibly  the  specific  gravity 
(buoyancy)  of  the  material  to  be  ground  is  a 
factor  which  deserves  more  consideration. 

John  W.  Bell. 

Montreal,  July  15. 

The  Editor  : 

Sir — I  have  read  with  much  interest  the 
letters  in  the  April  and  June  numbers  of  your 
magazine  by  Messrs.  J.  W.  Bell  and  W.  R. 
Bowling  on  the  subject  of  tube-mill  feeds. 
Part  of  Mr.  Bell's  letter  was  unintelligible  to 
me,  owing  to  a  slip  that  has  already  been 
pointed  out  by  Mr.  Bowling,  but  I  was  pleased 
to  see  him  open  the  discussion  of  a  subject 
which  presents  so  many  points  of  interest. 

Although  the  article  supplied  to  the  Mining 
and  Scientific  Press  by  Mr.  W.  Neal,  to 
which  Mr.  Bell  refers,  embodied  the  results 
of  some  research  work  done  by  me  in  March 
1909,  I  have  never  supposed  that  they  estab- 
lished a  rule  applicable  to  all  varieties  of  tube- 
mill  feeds,  since  the  variation  in  tonnage  and 
coarseness  of  sand  fed  during  the  series  of  ex- 
periments was  comparatively  slight.  I  am 
inclined  to  think  that  a  few  very  simple  rules 


224 


THE    MINING    MAGAZINE 


govern  the  variation  in  efficiency  of  a  tube- 
mill  indicated  by  tests  such  as  those  referred 
to.  The  thickest  discharge  that  I  have  been 
able  to  obtain  from  a  cone  fitted  with  a  suit- 
able diaphragm  contained 28% moisture.  Now, 
battery-sand  containing  28%  moisture  is  per- 
fectly fluid,  and  will  run  quite  easily  down  a 
25%  grade  ;  but  slime,  80%  of  which  will  pass 
a  200  mesh,  containing  28  or  30%  moisture,  is 
'  cake,'  as  no  one  will  need  to  be  reminded 
who  relies  on  this  property  for  the  satisfactory 
operation  of  leaf-filters. 

One  cannot  feed  a  22  or  24-ft.  tube-mill 
with  about  70  or  80  tons  of  sand  per  day  at 
30%  moisture  without  producing  a  discharge 
which  is  noticeably  viscous,  the  loss  in  fluidity 
being  indicated  by  a  rapid  rise  in  the  power 
necessary  to  drive  the  mill.  If  the  feed  is 
increased  to  200  or  more  tons  per  day  (I  am 
speaking  of  tough  quartz),  the  discharge  of  the 
mill  is  still  quite  fluid  at  34%  or  35%  moisture, 
and  it  becomes  advantageous  to  increase  the 
time  of  passage  of  the  pulp  through  the  mill 
by  reducing  the  dilution  to  a  point  depending 
on  other  circumstances. 

At  present,  my  experience  suggests  that, 
within  wide  limits,  the  best  results  should  be 
obtained  by  keeping  constant  the  quantity  of 
liquid  added,  so  that  the  dilution  falls  and 
rises  as  the  tonnage  rises  and  falls.  One  limit 
is  supplied  by  the  mill  in  which  the  tonnage 
has  been  reduced  until  the  percentage  of  mois- 
ture has  risen  above  40%,  and  the  other  is 
suggested  by  the  state  of  the  mill  referred  to 
by  Mr.  Dowling,  which  could  not  crush  400 
tons  per  day  at  a  low  dilution,  as  the  stream 
of  fluid  was  not  sufficiently  strong  to  wash  out 
the  fine  sand  accumulated  in  the  mill.  The 
latter  is  a  condition  of  which  I  have  no  ex- 
perience. I  have  intended  for  some  time  to 
investigate  this  question  further,  and  shall 
look  forward  to  the  publication  of  the  results 
of  the  series  of  experiments  referred  to  by  Mr. 
Bell.  If  these  are  not  already  concluded,  I 
would  suggest  that  the  results  be  reduced  on 
a  basis  that  shall  assign  "  metallurgical  value" 
to  different  pulps  according  to  the  area  of  sur- 
face exposed.  It  seems  to  me  that  the  calcu- 
lation of  relative  mechanical  efficiencies  from 
tables  of  Mechanical  Equivalents  '  brings  the 
fine-grinding  machines,  such  as  the  tube-mill, 
into  a  discredit  that  is  not  entirely  merited. 
Granting  that  any  system  one  may  adopt  for 
the  calculation  of  the  mechanical  values  of 
pulps  will  show  a  rapidly  decreasing  mechani- 
cal efficiency  as  the  material  treated  becomes 
finer,  I  wish,  nevertheless,  to  deprecate  the 
habit  of  considering  a  metallurgical  device  as 


though  it  were  a  power-station.  The  series 
of  mechanical  equivalents  calculated  by  Mr. 
Stadler  tempts  one  to  its  use,  as  there  seems 
only  small  scope  for  error  in  the  value  it 
assigns  to  the  finest  sizes  "  including  washed 
slime."  If,  however,  we  tabulate,  side  by 
side  with  Mr.  Stadler's  equivalents,  the  re- 
lative area  of  surface  exposed  per  unit  of 
weight,  we  find  an  enormous  increase  in  the 
value  to  be  given  to  the  very  sizes  in  which 
the  rise  of  mechanical  value  has  become  so 
slow.  This  has  been  sufficient  to  convince 
me  of  the  futile  nature  of  Mr.  Stadler's  method 
of  comparison. 

Although  we  are  not  yet  able  to  make  sizing- 
tests  on  pulp  finer  than  200-mesh,  there  are 
many  ores  in  the  world  whose  successful  treat- 
ment depends  on  the  presence  of  a  proportion 
of  300,  400,  or  even  1000-mesh  material  in 
the  pulp  as  treated.  Any  grinding  machine 
that  produces  such  material  in  large  quantities 
will  be  given  credit  for  it  in  any  fair  method 
of  comparing  efficiencies. 

It  would  be  interesting  to  know  what  form 
of  diaphragm  Mr.  Bell  has  found  to  give  the 
steadiest  discharge,  for  feeding  to  tube-mills. 
Convinced  that  the  function  of  the  diaphragm 
was  merely  that  of  a  mixer,  I  abandoned  the 
type  of  plate  developed  by  Mr.  Caldecott  some 
time  ago  and  now  use  a  round  plate  with  holes 
drilled  in  it  each  slightly  smaller  than  the  size 
of  the  discharge  to  be  used.  For  instance, 
for  a  6-ft.  cone,  I  use  a  plate  of  14-in.  dia- 
meter, with  12  holes  each  li  in.  diam.  Eight 
inches  above  this  comes  a  solid  plate  rivetted 
to  angle-irons,  so  as  to  leave  an  annular  space 
of  1*  in.  With  such  a  cone,  it  is  quite  easy 
to  get  a  thick  and  perfectly  steady  discharge, 
and  yet  keep  the  bed  of  sand  about  a  foot  be- 
low the  top  of  the  cone,  thereby  improving  the 
classification  effected. 

A.    QUARTANO. 

El  Oro,  Mexico,  July  28. 

Mine  Salting. 

The  Editor  : 

Sir — A  few  supplementary  remarks  might 
be  added  to  Mr.  T.  Lane  Carter's  article  in 
your  June  issue.  The  list  of  salting  tricks 
may  be  amplified,  thus  : 

The  interested  person  having  the  '  salt '  on 
the  top  of  his  hat-brim,  and  allowing  it  to  fall 
in  the  sample  as  he  casually  inspects  the  work ; 
having  pieces  of  the  rich  ore  inside  his  trousers 
band,  and  slipping  these  into  the  reduced  sam- 
ple ;  having  the  '  salt '  in  a  hollow  lead  pencil, 
or  pencil-holder,  or  within  a  cavity  near  the 
bottom  of  his  walking-stick  ;  in  cigarette,  pipe, 


SEPTEMBER,    1911 


225 


or  chewing  tobacco.  Or,  being  curious  as  to 
how  it  is  all  being  done  and  showing  an  in- 
telligent interest  in  the  various  steps,  the  guile- 
less owner  may  try  to  poke  around  in  the 
sample  with  his  sore  finger,'  around  which  a 
rag  is  tied,  or  under  the  finger-nail  of  which 
the  '  salt '  reposes.  An  acquaintance  once  told 
me  how  he  had  caught-on  to  an  attempted 
'sweetening'  during  a  placer  inspection.  He 
noticed  in  each  pan  washed  for  him  by  the 
guiding  and  obliging  owner  the  same  shaped 
little  nugget.  It  took  some  time  to  find  out 
that  his  guide  and  mentor,  who  was  an  excep- 
tionally expert  panner,  was  catching  the  gold 
after  each  panning  and  holding  it  there  while 
the  pan  was  being  filled  with  fresh  dirt.  Of 
course  this  would  have  had  no  bearing  in  a 
formal  examination,  but  it  might  have  caused 
the  starting  of  a  useless  and  expensive  investi- 
gation. 

The  plain  moral  of  the  foregoing  is  to  keep 
all  outsiders  away  from  the  work,  especially 
during  the  reduction  of  the  samples,  but  this 
is  not  always  as  easy  as  it  sounds,  particularly 
when  on  preliminary  inspections  and  when 
among  natives  having  no  conception  of  the 
ethics  of  the  case.  Ethics  or  no  ethics,  how- 
ever, the  diplomatic  engineer  will  compass 
their  absence  when  occasion  demands  it. 

Emphasis  might  be  laid  on  some  of  the 
precautionary  measures  mentioned  by  Mr, 
Carter,  such  as  panning,  the  taking  of  dummy 
and  of  duplicate  samples,  the  making  up  of 
composite  '  samples  ;  and,  particularly,  the 
cleaning  of  the  faces  prior  to  taking  the  sam- 
ple ;  even  going  to  the  extent  of  moiling  pre- 
liminary cuts  when  thought  expedient.  (A 
whisk  broom  ought  to  be  a  part  of  every 
sampler's  kit.)  And  if  a  description  is  written 
of  each  face  sampled,  and  a  note  made  of  its 
probable  assay,  the  engineer  will  find  it  of 
assistance,  in  detecting  any  '  monkeying,'  and 
in  other  ways. 

Constant  watchfulness  is  demanded  over 
the  whole  work,  but  especially  over  the  finished 
samples.  After  these  are  down  to  pulp-size 
extra  precaution  should  be  taken  against  the 
well  advertised  hypodermic.  I  recall  hearing 
of  an  engineer,  who  after  the  mine  had  failed 
to  hold  up  to  his  sampling,  discovered  a  needle- 
hole  in  the  bottom  edges  of  his  sample-enve- 
lopes. And  I  suppose  everyone  has  heard  of 
the  exchanging  of  samples  by  means  of  ripping 
and  re-sewing  of  their  receptacles.  I  find  it 
convenient  to  have  a  large  box  in  which  the 
bagged  samples  can  be  locked  during  the  pulp- 
ing operations,  or  until  I  am  ready  to  '  pull 
out.'     Such  a  box  can  usually  be  found  around 


the  plant  (tool -boxes,  etc.),  or  else  quickly 
knocked  together  out  of  rough  lumber.  All 
chinks  and  cracks  should  be  stopped,  from  the 
inside,  and  the  whole  inside  so  marked  and 
sealed  that  no  portion  can  be  moved  without 
it  being  detected.  This  box  can  be  sealed 
"also  on  the  outside  by  a  thin  inconspicuous 
thread,  or  piece  of  horse-hair,  and  more  osten- 
tatiously by  the  engineer's  private  wax-seal 
and  peculiar  string.  It  is  safest  to  also  seal 
all  windows,  screens,  and  doors  of  the  assay- 
office,  or  wherever  the  samples  and  flux  are 
stored.  A  trunk  or  two  would  serve  the  same 
purpose  as  the  box  ;  but  safety — aside  from 
salting  risks — rests  in  good-sized  samples  as 
well  as  a  large  number  of  these.  Locked 
leather  bags  are  very  handy  to  have  along, 
and  conduce  to  one's  peace  of  mind.  Even 
if  the  engineer  feels  morally  certain  that  no 
one  interested  would  tamper  with  him,  he 
should  endeavour  to  be  in  the  position  where 
he  could  always  swear  no  one  has.  When 
put  in  the  latter  light  to  honest  but  sensitive 
owners  a  clearing  of  the  atmosphere  can 
usually  be  noticed. 

Dumps  are  always  open  to  suspicion,  especi- 
ally small  ones,  but  nevertheless  they  should 
be  closely  studied  as  they  may  throw  light  on 
the  mineralization,  etc.  Even  a  passing  glance 
of  a  dump  from  a  long  cross-cut  tunnel,  caved 
at  the  end,  but  showing  no  quartz,  might  in- 
dicate that  the  prominent  surface  showings 
either  did  not  go  down  or  that  the  tunnel 
workings  bad  not  penetrated  to  them,  despite 
the  owner's  assertions  to  the  contrary.  (Owner 
wanting  the  tentative  purchasers  to  have  the 
cleaning  out  done  for  their  account). 

But,  after  all,  the  engineer's  best  protection 
is  common  sense,  power  of  observation,  and 
ability  to  read  human  nature.  He  has  to 
place  more  or  less  trust  in  others.  The 
'  pumping '  of  the  natives,  getting  their  ideas 
of  things  in  general,  and  of  the  special  pro- 
perty in  particular,  is  a  helpful  practice.  For 
instance,  if  a  series  of  exciting  samples  has 
been  got  from  a  mine  out  of  which  no  such 
ore  was  known  by  the  neighbours  to  have 
come  before,  it  would  behove  the  engineer 
to  look  out,  and  into,  again. 

Happily  there  is  now,  as  Mr.  Carter  makes 
mention,  much  more  talk  of  salting  '  than 
'  doing.'  No  doubt  the  world  is  getting  better 
and  the  "  bully  honest  miner,"  of  Dan  de 
Quille,  is  getting  more  honest  ;  perhaps  the 
decline  of  the  custom  of  making  cash-down 
payments  may  have  something  to  do  with  it. 
And  while  on  this  subject  the  '  dressing '  of  a 
mine  might  be  touched  on,  as  it  is  apt  to  be 


226 


THE    MINING   MAGAZINE 


more  bothersome  than  salting.  By  'dressing' 
is  meant,  as  I  understand  it,  the  preparing  of 
the  mine  for  a  sale  by  the  placing,  and  the 
stopping,  of  the  openings  where  they  will  do 
the  most  good — grooming  it,  as  it  were.  As 
in  a  horse  trade,  this  sort  of  thing  is  not 
entirely  and  absolutely  reprehensible.  The 
owner,  especially  of  a  new  property,  would 
be,  as  a  rule,  foolish  not  to  do  his  work  at  the 
most  promising  spots.  And  the  seller  is  not 
bound  to  call  attention  to  the  weak  points  of 
the  property — that  is  'up  to  '  the  examining 
engineer.  So  this  dressing  process  is  apt  to 
cause  the  engineer  some  worry  in  giving  it  the 
proper  '  weighting  '  in  the  forming  of  his  judg- 
ment. For  it  is  nearly  as  bad  to  overlook  a 
good  property  as  it  is  to  recommend  a  poor 
one. 

W.    N.    CUMMINGS. 

Tucson,  Arizona,  July  12. 

[This  is  a  subject  of  perennial  interest. 
The  suggestions  made  by  Mr.  Cummings 
should  prove  useful,  especially  to  the  younger 
members  of  the  profession  when  engaged  in 
'  scouting.' — Editor] 

Pebbles  for  Tube-Milling. 

The  Editor  : 

Sir — Mr.  Mackay's  letter  in  your  July  issue 
with  reference  to  the  manufacture  of  pebbles 
at  the  Ceniza  mill,  near  Parral,  lacks  many 
details,  which  I  should  have  added  to  such  a 
contribution  had  I  considered  the  matter  worthy 
of  publication  by  itself. 

With  imported  flints  at  the  prohibitive  price 
of  ;^15  per  ton,  delivered  at  the  mine,  the 
question  was  not  so  much  a  comparison  be- 
tween the  cost  of  imported  and  locally  made 
pebbles  as  the  difference  of  efficiency  in  the 
use  of  raw  or  prepared  mine-rock.  By  giving 
the  rock  an  eight  or  ten  hour  '  rounding-off ' 
in  the  mill,  and  afterward  sorting  out  the  good 
pebbles  resulting,  a  distinct  advance  over  the 
ordinary  practice  in  using  mine  -  rock  was 
made.  The  danger  of  chokage  of  the  spiral 
feed  was  obviated,  an  occurrence  that  is  com- 
mon where  a  spiral  of  ordinary  diameter  is 
used,  and  jagged  rock  introduced  to  the  feed. 
The  mill  (provided  the  feed  was  kept  at  the 
correct  proportion  of  moisture),  was  operated 
at  a  maximum  efficiency,  and  theusual  troubles 
inside  and  outside,  resulting  from  the  use  of 
raw  mine-rock  and  the  consequent  formation 
of  gravel  and  small  pebbles  (due,  respectively, 
to  chipping  and,  in  some  cases,  fracture  of  the 
stone),  were  avoided.  Every  pebble  intro- 
duced into  the  mill  had  been  previously 
proved. 


In  the  case  of  the  Ceniza  mill  the  explana- 
tion may  be  necessary  that  the  fine-grinding 
department  was  ready  before  the  rest  of  the 
equipment  was  erected,  and  the  opportunity 
was  taken  to  utilize  it  for  the  above  purpose. 
It  was  soon  found  that  a  considerable  tonnage 
of  excellent  pebbles  could  be  prepared  at  a 
minimum  of  time  and  cost,  each  charge  of  raw 
rock  filling  the  mill  just  over  half-full. 

Should  the  idea  meet  with  the  approval  of 
other  metallurgists  situated  where  flint  or 
especially  tough  stone  is  available,  I  would 
suggest  the  erection  of  a  small  mill  for  the 
especial  purpose,  fitted  with  ribbed  liners,  and 
with  a  possible  arrangement  of  continuous 
feed  of  rock  and  a  continuous  discharge  of 
pebble  and  gravel. 

A.  W.  Allen. 

London,  September  5. 

German  Ironmasters  are  keenly  search- 
ing for  foreign  supplies  of  iron  ores.  Large, 
shipments  are  obtained  from  Lapland  and  it 
is  an  open  secret  that  the  iron  resources  of 
Morocco  are  the  ultimate  cause  of  the  present 
political  crisis.  They  are  carrying  their  econ- 
omic warfare  with  France  nearer  home  by 
putting  capital  into  Normandy  especially  at 
Briey.  The  output  of  this  district  during 
1910  wasl,605,000  tons,  of  which  one  half 
was  used  by  French  firms,  and  the  remainder 
despatched  to  Belgium  and  Germany.  The 
proportion  sent  to  Germany  will  probably  in- 
crease during  the  next  few  years. 

A  water-softening  process,  originated 
in  Germany  and  already  m  successful  use  on 
the  Great  Northern  railway  in  England,  has 
recently  been  introduced  into  New  York,  and 
is  arousing  keen  interest.  The  process  has 
been  installed  on  an  experimental  scale  at  one 
of  the  Standard  Oil  Co.'s  plants,  and  also  at 
a  point  on  the  New  York  Central  railroad. 
It  appears  to  be  successful.  The  process 
consists  in  allowing  boiler-feed  water  to  flow 
in  a  thin  film  down  a  steeply  inclmed  alu- 
minium, plate,  exposed  to  the  full  rays  of  the 
sun.  No  chemical  change  between  top  and 
bottom  of  the  plate  can  be  detected,  but  on 
evaporation  in  a  boiler,  the  water  thus  treated 
forms  an  impalpable  sediment  instead  of  the 
usual  hard  scale,  and  not  only  this,  but  it  will 
decompose  any  scale  previously  accumulated 
from  untreated  water.  The  causes  of  this 
phenomenon  are  obscure,  but  the  aluminium 
plate  and  the  sunshine  seem  to  be  essential 
elements.  After  treatment,  the  water  can  be 
stored  over-night,  or  through  a  cloudy  season, 
without  loss  of  its  virtues. 


SEPTEMBER,    1911 


227 


PRECIS  OF  TECHNOLOGY 

Alloys  of  Refractory  Metals. — In  Metallurgical 
and  Chemical  Engineering  for  July,  Hans  Gold- 
schraidt,  of  Essen,  discusses  the  solubility  of  refractory 
metals  as  affecting  their  alloying  capacity.  His  reason 
for  writing  the  article  is  that  many  users  of  refractory 
metals  have  an  idea  that,  because  those  produced  by 
his  alumino-thermic  process  are  free  from  carbon  and 
therefore  have  higher  melting  points,  they  are  not  so 
suitable  for  alloying  purposes.  He  points  out  that  the 
alloying  capacity  of  a  refractory  metal  with  one  of 
lower  melting  point  is  not  a  function  of  the  melting 
point  of  the  former  but  of  the  solubility  of  the  former 
in  the  latter.  This  contention  is  fully  proved  in  prac- 
tice. Carbon-free  chromium  melts  at  2822°  F,  but  is 
well  known  to  alloy  readily  with  molten  steel.  Carbon- 
free  manganese  melts  at  2273^'  F.  and  alloys  even 
better  with  copper  than  ordinary  manganese.  Ferro- 
titanium    produced    by    the  alumino-thermic   process 


is  subsequently  divided  into  compartments  as  shown. 
This  construction  forms  the  novelty  in  the  present 
case.  The  steel  shoe  is  about  4  ft.  high,  made  in  four 
segments,  the  steel  being  §  in.  thick,  with  vertical 
webs  rivetted  to  the  sides  of  the  shoe  by  angle  irons. 
The  shoe  after  being  built  in  position  is  filled  with 
concrete.  The  earth  is  then  dug  out  from  the  centre 
and  the  shoe  gradually  falls.  As  it  does  so,  the  walls 
are  built  up  upon  it  with  a  circular  steel  form  on  the 
outside  and  wooden  forms  in  the  inside.  Circular 
horizontal  rods  of  ^  in.  square  steel  are  embedded  in 
the  concrete,  and  also  two  sets  of  vertical  rods,  one 
near  the  outside  periphery  and  the  other  near  the  in- 
side surface.  When  the  shaft  has  sunk  to  a  depth 
where  much  water  and  gravel  come  in  at  the  bottom, 
preparations  are  made  for  the  use  of  compressed  air. 
A  timber  deck  is  built  across  the  shaft,  caulked  with 
oakum,  covered  with  concrete,  and  lined  on  the  lower 
side  with  clay  plaster.  The  men  excavate  for  a  few 
feet  below  the  shoe  and  the  material  is  drawn  up  by 


Water,  sand^^z 
and  ^/r   -/P^/ 


To  Compressor 


Horizontal 
re  in  forcing 
rods 


Steel  shoe 
ofs/a/n  p/sie 


HORIZONTAL  AND   VERTICAL    SECTIONS  OF  CONCRETE  SHAFT 


melts  at  2426°  F  and  dissolves  easily  and  uniformly 
in  molten  steel.  Experience  generally  shows  that  these 
carbon-free  metals  are  actually  more  soluble  than 
those  containing  carbon,  though  the  latter  have  lower 
melting  points.  In  explaining  the  theory  of  solution  of 
one  metal  in  another,  Mr.  Goldschmidt  quotes  the 
case  of  platinum  which  is  soluble  in  tin  and  lead,  and 
the  consequent  astonishment  of  the  young  chemist 
who  tries  to  melt  these  metals  in  a  platinum  crucible. 
Concrete  Shafts. — In  the  Mining  and  Engineering 
World  for  May  29,  P.  B.  McDonald  describes  the 
method  of  sinking  through  watery  strata  at  the  Rogers 
mine,  Iron  River,  Michigan.  Briefly,  the  method  is 
a  variation  of  that  by  which  the  shaft  is  built  of  rein- 
forced concrete  and  sinks  as  the  material  is  dug  away 
from  the  cutting  edge,  by  men  in  a  compressed-air 
caisson.  The  shaft  is  29  ft.  outside  diameter,  but  the 
cross  section  is  not  annular  ;  instead,  the  internal  space 
is  made  of  rectangular  cross-section  16^  by  11  ft.,  and 


bucket  or  by  dredge.  During  this  time  the  shaft  does 
not  fall  owing  to  the  atmosphere  of  compressed  air. 
The  men  then  come  to  surface  and  the  air  pressure  is 
released,  thus  allowing  the  shaft  to  sink.  The  cycle 
of  operations  is  continued  until  the  work  is  com- 
pleted. 

Queensland  Miners'  Health  Commission. — The 
Queensland  Government  Mining  Journal  for  July 
contains  the  text  of  the  report  of  a  Commission  re- 
cently appointed  to  investigate  several  points  in  con- 
nection with  the  health  of  underground  workers  in  die 
mines  of  that  state.  The  first  field  of  inquiry  was  a 
general  one  relating  to  the  "  Conditions  of  work  in  re- 
lation to  the  health  of  the  miners  "  ;  the  second  related 
to  the  amount  of  pulmonary  diseases  prevalent  ;  and 
the  third  was  a  consideration  of  the  expediency  of  pre- 
venting tuberculous  subjects  from  doing  mining  work 
and  of  suitably  compensating  them  for  the  loss  of  their 
employment.     As  regards  general  conditions  the  Com- 


228 


THE    MINING    MAGAZINE 


missioners  are  of  opinion  that  the  Regulation  of  1910 
relating  to  efficient  ventilation  (described  in  our  issue 
of  April  last)  is  sufficient  for  the  purpose  of  maintain- 
ing a  pure  atmosphere  and  of  reducing  the  tempera- 
ture of  the  workings,  except  perhaps  at  Charters 
Towers  where  the  atmosphere  in  the  deep  mines  is  hot 
and  moist.  The  law  already  allows  inspectors  to  en- 
force the  use  of  sprays  or  other  allayers  of  dust  in 
rock-drill  operations,  but  the  Commissioners  recom- 
mend similar  powers  in  connection  with  the  handling 
of  ore  at  other  points  such  as  after  blasting  and  during 
loading  into  skips.  They  also  have  many  recommen- 
dations about  drinking  water,  sanitation,  etc.  Their 
enquiries  into  the  subject  of  pulmonary  complaints 
disclosed  the  fact  that  fibrosis  and  tuberculosis  are 
prevalent  only  to  a  limited  extent  and  are  confined  to 
dry  and  dusty  quartz  mines,  but  that  they  are  gradu- 
ally on  the  increase.  The  recommendations  in  Part  1 
of  the  inquiry  will  go  a  long  way  toward  improving 
the  conditions,  but  the  Commissioners  are  in  favour  of 
the  additional  drastic  proposition  under  Part  3 ,  namely 
that  miners  should  be  required  to  obtain  medical  cer- 
tificates once  a  year  to  prove  their  immunity  from 
pulmonary  complaints,  and  that  some  sort  of  general 
insurance  scheme  should  be  inaugurated  by  the  State 
to  provide  for  such  as  are  rejected.  This  part  of  the 
recommendations  is  of  far  reaching  importance,  and 
will  raise  much  discussion  in  other  countries  as  well 
as  in  Queensland. 

Salt  from  Salt  Lake. — In  the  Engineering  and 
Mining  Journal  for  JulyS,  Percy  E.  Barbour  describes 
the  methods  of  e.xtracting  salt  from  the  waters  of  Salt 
Lake,  Utah.  This  lake  is  about  73  miles  long  and  30 
miles  wide.  It  is  quite  shallow,  being  never  more  than 
50ft  deep,  and  averaging  30  ft.  The  shores  are  flat, 
and  even  a  small  variation  in  the  depth  causes  a  large 
increase  or  decrease  in  its  area.  The  level  alters  from 
year  to  year,  and  during  the  seasons  of  each  year. 
When  the  level  is  low,  the  specific  gravity  of  the  water 
is  higher  than  when  more  water  is  present,  but  the 
average  is  about  ri5,  compared  with  1  02  of  sea  water. 
With  the  exception  of  the  Dead  Sea  the  water  is  the 
densest  known.  It  contains  from  15  to  22%  by  weight 
of  salts,  or  nearly  five  times  as  much  as  the  Atlantic 
Ocean.  The  accumulation  of  salt  is  due  to  the 
evaporation  of  the  water  from  tributary  streams 
which  bring  down  small  proportions  of  saline  mat- 
ter. An  analysis  of  the  water  gives  the  following 
contents  in  grammes  per  litre  ;  Sodium  chloride 
193  ;  magnesium  chloride  15  ;  potassium  sulphate 
8|  ;  sulphate  of  lime  8j ;  magnesium  sulphate 
5i  ;  lithium  sulphate  -|.  Two  companies  are  engaged 
in  making  commercial  salt  from  the  water  ;  the  larger 
of  these  two  firms  is  the  Inland  Crystal  Salt  Co.  of 
which  J.  F.  Smith,  the  head  of  the  Mormon  church, 
is  president.  At  this  company's  works  the  water  is 
pumped  during  May  each  year  to  settling  ponds  two 
miles  away  by  pumps  that  handle  7000  gal .  per  minute. 
In  these  ponds  the  solid  foreign  matters  are  deposited, 
and  evaporation  proceeds  until  the  salt  content  is 
raised  from  15  to  22%  by  weight.  The  brine  then  goes 
to  '  stock  '  ponds  where  further  evaporation  brings  the 
salinity  to  26%,  and  afterward  to  '  harvesting  '  ponds 
where  the  salt  crystallizes  upon  a  prepared  floor  of 
salt.  There  are  35  'harvesting'  ponds  of  9  acres 
each,  but  only  10  or  15  are  at  present  in  use. 
The  salt  deposited  varies  from  2  to  6 in.  in  thick- 
ness and,  after  the  remaining  liquor  has  been 
drained  off  and  returned  to  the  lake,  the  salt 
is  ploughed  by  horse-power  and  stored  in  piles  at  the 
side  of  the  ponds.  Naturally  the  weather  has  con- 
siderable  effect    on    the  process  in   many  ways,    the 


humidity  and  rainfall  lengthening  the  time  of  evapora- 
tion and  the  latter  sometimes  dissolving  much  of  the 
salt  in  the  piles  during  the  autuum.  In  1910  the  acre- 
age '  harvested  '  was  100,  from  which  50,000  tons  was 
removed,  or  500  tons  per  acre.  This  however  was  an 
exceptional  year  and  250  to  300  tons  is  nearer  the  aver- 
age. Corresponding  figures  at  the  French  Atlantic 
works  where  sea-water  is  evaporated  are  06  to  1 1  tons, 
at  the  French  Mediterranean  works  12  to  23  tons,  and 
at  the  Corsican  works  68  tons  per  acre.  The  crude 
salt  produced  by  the  Inland  Crystal  Co.  contains 
9785%  sodium  chloride,  15%  water,  and  the  remain- 
der consists  of  small  quantities  of  other  salts.  Some  of 
the  crude  salt  is  sold  without  further  treatment, and  some 
is  refined  for  table  use,  until  it  contains  99  5%  NaCl. 

Concentration  at  Frontenac  Consolidated. — In  our 
issue  of  May  1910  we  quoted  the  prospectus  of  a  com- 
pany formed  in  London  to  acquire  the  Frontenac  and 
Aduddel  gold  mines  situated  near  Central  City,  Gilpin 
county,  Colorado.  It  has  been  possible  to  re-open  these 
old  mines  owing  to  the  fact  that  the  Newhouse  tunnel 
has  intersected  the  vein  at  1800  ft.  below  surface.  The 
ore  consists  of  a  mixture  of  pyrite,  galena,  and  tetra- 
hedrite  in  a  quartz  gangue.  The  gold  content  averages 
6  to  7  dwt.  per  ton  and  is  found  chiefly  in  the  pyrite ; 
in  addition  4  to  6oz.  silver  is  present  associated  with 
the  tetrahedrite.  Until  recently  the  ore  was  treated  in 
the  usual  local  way  by  amalgamation  and  concentra- 
tion. On  the  formation  of  the  English  company  it 
was  decided  to  bring  the  treatment  up  to  date,  and,  as 
little  precious  metal  is  associated  with  the  quartz,  to 
omit  the  amalgamation.  Mining  Science  for  July  20 
describes  the  new  concentrating  plant  which  has  been 
designed  by  Henry  P.  Lowe,  managing  director,  and 
S.  B.  Tyler,  superintendent.  The  plant  is  capable  of 
treating  200  tons  per  day  and  produces  five  different 
classes  of  concentrate.  The  ratio  of  concentration  is 
4  to  1,  and  the  recovery  is  85%  of  the  gold  and  78% 
of  the  silver  content.  The  accompanying  flow-sheet 
explains  the  treatment.  The  ore  is  broken  to  2  inch 
size  and  then  passed  to  three  sets  of  rolls.  The  first 
rolls  are  spaced  1  in.  apart  and  the  discharge  is  sent  to 
a  trommel  having  apertures  corresponding  to  3  mesh. 
The  oversize  goes  to  second  rolls,  and  the  ore  passing 
through  is  sent  to  a  second  trommel  with  6  mesh  aper- 
ture. The  oversize  from  these  goes  to  the  coarse  jigs 
from  which  the  tailing  goes  to  the  second  rolls.  The 
ore  passing  the  second  trommel  goes  to  a  third  trommel 
with  10  mesh  aperture,  the  oversize  of  which  goes  to 
second  jigs.  The  tailing  from  the  second  jigs  goes  to 
the  tube-mills.  The  hutch  product  of  the  two  sets 
of  jigs  consists  of  galena  and  pyrite.  The  undersize 
from  the  last  trommels  passes  to  a  cone  thickener, 
from  which  the  overflow  is  sent  to  the  slime  depart- 
ment, and  the  thickened  pulp  goes  to  Flood  tube- 
classifiers  where  four  sizes  are  produced.  These  pro- 
ducts are  treated  on  Card  tables  which  yield  concen- 
trates of  galena  and  pyrite.  The  lead  concentrate 
carries  a  large  proportion  of  geld ,  and  the  pyrite  carries 
copper,  and  the  two  about  equally  share  the  silver. 
The  tailing  contains  practically  no  lead.  The  middling 
from  the  four  sets  of  Card  tables  joins  the  tailing  from 
the  second  jigs  and  the  mixture  is  sent  to  tube-mills 
(of  which  onl)'  one  is  in  use  at  a  time)  where  it  is  re- 
duced to  40  mesh.  The  discharge  is  mixed  with  the 
slime  overflow  of  the  thickener  above  mentioned  and 
sent  to  another  thickener,  from  which  the  overflow 
goes  to  Callow  tanks  and  to  No.  3  Deister  slime-tables, 
while  the  underflow  goes  to  Flood  classifiers  and  to 
Card  slime-tables.  The  middlings  from  the  Card  and 
Deister  tables  are  re-treated  on  second  tables  without 
any  re-grinding.     The  slime  concentrate  contains  cop- 


SEPTEMBER,    1911 


229 


perand  silver  with  somegold.    The  following  table  gives 
particulars  of  the  contents  of  the  various  concentrates  : 
Gold,      Silver, 


Oz. 

Oz. 

Lead 

Copper 

Silica 

Concentrate. 

per  ton. 

per  ton. 

% 

% 

% 

Tiorc        

.      070 
.      060 

12 

11 

10 

12 
20 

10 

J '6^ 

Card  Iron  

9 

Card  Lead 

.      500 

12 

37 

— 

— 

First  Slime  .... 

.      045 

12 

— 

30 

20 

Second  Slime.. 

.      040 

12 

— 

3  to  4 

30 

Ore  from  Mine 

T 


250  Ton  Receiving  Bin 
■«- Shaking  Grizzley 
I3in»24in  Blake  Crusher 


2  Sels  Rolls  I6inx36in 

1 

Elevator 


Elevahor 

~~l . 

250  Ton  Roll  Bin 

1 

N?l  Rolls     I6in  x36m 

Elevator 
Flood  Aulomatic  Sampler 


(l6inBelK  I4in  Buckehs) 


(16  in  Belt.  14-in  Buckets) 


t 


2  - 4a"in  «72in Trommels ,  3  mesh. 


I  Doub* 


e    2  Comp     Jig 


.«  2  •  4B in  » 7?  in  trommels,  6  mesh 


r 


<  2  -  48  in  »  108  in  Trommels  .  10  mesh 


2Dbl     2  Comp    Jigs 


I    5ft.  Cone  Pulp  Thickener       ^  Slime  overflow 
3    Flood     ClassiFiers 


Tail 


Coarse 
2  Card 'rabies    2  Cards  2  Cards    I  Card  Table 


Medium 


Fine 

T 


Finest 


"TT^TT'"^ 


Concentrate 


I.  5ft  Cone  Thickener  . 


Middling 


Middling 


2.6ft»l2ft  Tube-Mills 


Reground  Middling  _40me5h 


Eleva 


3ror 


3  8 fl.  Callow  Tanks 
3.  Oeister  N°3  Tables 


-2-5ft  PulpThickener 
I 
6  Flood  Classifiers 


Tai  I  inq 


Coarse 
3  Cards 


Medium 
3  Cards 


Fine 
3  Cards 


Concentrate 


Middling  Middling         Middling        Middling        | 


Tailing 


I  Deister  N*3 


I.  Card 


I  Card 


Concentrate 


1=^1 


Flow-Sheet  of  Fronfenac  Concentration  Plant- 


As  already  mentioned  85%  of  the  gold  and  78%  of 
the  silver  is  recovered  ;  the  following  table  shows  how 
the  recovered  metals  are  distributed  in  the  various 
concentrates  : 

Concentrate  % 

Jig 18 

Card  Iron 44 

Card  Lead 6 

First  Slime 29 

Second  Slime 3 

Total 100 


Concentrating  Silver  Ore  at  Cobalt. — The  Cana- 
dian Mining  Journal  for  July  15  contains  a  paper  by 
A.  P.  Globe,  mill  manager  of  the  McKinley  Darragh 
mine  at  Cobalt,  Ontario,  describing  the  concentration 
plant  erected  there.  The  ore  as  it  comes  from  the  mine 
is  hand-picked  in  the  first  grizzly,  and  also  after  coarse 
breaking.  It  is  then  crushed  to  1|  in.  and  screened, 
the  oversize  being  sent  to  coarse  jigs,  and  the  under- 
size  sent  together  with  the  hutch  product  of  the  jigs 
to  another  screen.  From  the  latter 
the  oversize  goes  to  a  fine  jig,  and 
the  undersize  separated  into  sand 
and  slime.  The  slime  forms  about 
1%  of  the  total  ore  and  averages  200 
oz.  silver  per  ton,  so  it  is  not  concen- 
trated further  but  shipped  direct  to 
the  smelter  ;  the  sand  goes  to  the 
Wilfiey  tables  mentioned  hereafter. 
The  tailing  from  the  coarse  jigs  goes 
to  a  battery  of  30  stamps,  from  which 
the  pulp  is  classified,  the  oversize  go- 
ing to  a  Hardinge  conical  mill  to- 
gether with  the  tailing  from  the  fine 
jig.  The  combined  pulp  is  classified 
and  sent  to  Wilfleys,  Deister  tables 
and  Frue  vanners.  The  tailing  from 
the  Wilfleys  is  re-ground  in  a  tube- 
mill  and  treated  on  a  Deister  table 
and  Deister  slime-tables.  The  tail- 
ing from  the  Frue  vanners  is  passed 
over  Deister  slime-tables.  All  the 
slime-tailing  is  passed  over  canvas 
sheets.  The  average  assay  of  the  ore 
is  43  oz.  silver  per  ton  and  of  the  final 
tailing  4oz.,  giving  an  extraction  of 
90%.  According  to  the  present  ar- 
rangement very  little  rich  ore  is  re- 
moved by  hand-picking,  but  before 
l^ng  a  more  elaborate  plant  will  be 
erected  for  this  purpose.  The  cost 
of  concentration  is  low,  being  only 
$130  per  ton  milled 

Ore  in  Clay   Selvages.  —  At  the 
*  '  June  meeting  of  the  American  Insti- 

( 16  in  Belt.  I4in  Buckets)     ^^g  of  Mining   Engineers,    Charles 
R.  Keyes  presented  a  paper  discuss- 
ing the  origin  of  silver  bonanzas  in 
the  arid  regions  of  the  United  States 
and  Me.xico.     He  agrees  that  these 
deposits  are  not  derived  from  below, 
but  are  due  to  meteoric  and  other  de- 
scending waters  charged  with  salts. 
In  every  case  known  to  him  they 
are  associated  with  the  clay  selvage  of 
brecciated  and  sheared  belts,  joints 
and    fracture    crevices,    and     fault- 
planes.    The  miners  as  a  rule  follow 
the  clay,   but    engineers   have  only 
casually  referred  to  the  fact  that  the 
silver  is  found  richest  at  these  spots. 
Mr.  Keyes  takes  up  the  subject  and  founds  the  theory 
that  descending  waters  containing  salts  will  precipitate 
their  valuable  bases  on  coming  into  contact  with  the 
alkaline  silicates  of  the  clay.      He  quotes  Lindgren  and 
Emmons,  who  have  shown  that  the  presence  of  kaolin 
is  a  priori  evidence  of  downward  sulphide  enrichment, 
and  urges  that  the  theory  is  of  wider  application  than 
either  was  aware.      He  believes  that  similar  pheno- 
mena are  to  be  found  in  almost  every  type  of  deposit 
wherever  there  are  descending  waters  charged  with 
salts,  but  they  are  specially  noticeable  in  desert  de- 
posits, because  the   thickness  of  the  gossan  zone  is 


Finest 
I  Card 


I  Card 


230 


THE    MINING    MAGAZINE 


great,  and  this  feature  is  therefore  prominent  and 
characteristic.  The  above  is  a  mere  outHne  of  Mr. 
Keyes'  chief  proposition  ;  his  paper  should  be  read  in 
fuli.  We  may  add  that  his  argument  is  based  by 
analogy  on  researches  connected  with  agricultural 
chemistry. 

The  Aluminium  Industry.— T/je  Electrical  Review 
(London)  quotes  a  paper  by  W.  Kossmann  and  pub- 
lished at  Strassburg,  on  the  economic  development  of 
the  aluminium  industry.  Mr.  Kossmann  gives  175 
metric  tons  as  the  production  in  1890.  This  had  in- 
creased to  7300  tons  in  1900,  11,500  tons  in  1905,  and 
34,000  tons  in  1910.  The  following  are  the  present 
producers  of  the  metal  and  their  individual  outputs 
for  1910  : 


and  the  works  outside  the  syndicate  began  to  place 
aluminium  on  the  market  below  the  convention  prices. 
During  1908  the  management  of  the  syndicate  was 
compelled  to  reduce  the  price  several  times  without 
attaining  the  desired  results,  and  the  syndicate  was 
dissolved  at  the  close  of  September  in  that  year,  when 
the  price  further  declined  in  consequence  of  the  com- 
petition for  orders.  Contracts  were  even  concluded 
at  the  close  of  1908  at  Is.  l^d.  per  kilogramme,  a  rate 
which  is  declared  not  to  have  covered  the  costs  of 
most  producers. 

The  author  states  that  the  syndicate  fixed  the  divi- 
sion of  the  total  quantity  to  be  offered  for  sale  among 
the  members  according  to  a  percentage  basis,  whilst, 
at  the  same  time,  specified  markets  were  allotted  to 


Companies 


Country 


Production  in 

Metric  tons  in 

1910 


Aluminium  Industrie  Gesellschaft,  Neuhausen,  etc. 
Societe  Electro-Metallurgique  Francaise,  Froges 
Compagnie  des    Produits   Chimiques   d'Alais  et    de    1 

Camarque,  Salindres 
British  Aluminium  Co. 
Aluminium  Company  of  America 
Northern  Aluminium  Co.    ... 
Societe  des  Forces  Motrices  et  Usines  de  I'Arve 
Societe  des  Produits  Electro-Chimiques  et  Metallurgi 

ques  des  Pyrenees    ... 
Societe  Electro-Metallurgique  du  Sud-Est 
Societe  d'Electrochemie 
Gebruder  Giulini,  Ludwigshafen 
Societe  Italiana  per  la  Fabbricazione  dell'  Aluminio 
Anglo-Norwegian  Aluminium  Co.     ... 


Switzerland,  Austria,  and  Germany 
France  ... 

France  ... 
Scotland 
United  States 
Canada... 
France  ... 

France  ... 
France  ... 
France  ... 
Switzerland 
Italy 
Norway... 


6000 
6000 

2500 

4000  to  5000 

12,000 

600 

500 
300 
300 
400 
600 
500 


The  first  five  in  the  list  account  for  90%  of  the  output. 
France  and  North  America  are  about  equal  in  point 
of  production  and  are  substantially  in  front  of  any 
other  country.  It  is  notable  that  only  one  works  is  in 
Germany,  that  at  Rheinfelden,  Baden,  belonging  to 
the  Neuhausen  Co.  ;  the  relative  importance  of  Ger- 
man production  has  changed  entirely  during  the  past 
ten  years.  Water  power  has  been  a  more  important 
factor  in  locating  the  works  than  the  supply  of  the 
raw  material.  The  price  was  as  much  as  /50  per 
kilogramme  in  1855.  In  1890  the  quotation  was 
27s.  6d.  ;  2s.  in  1900,  3s.  3d.  to  3s.  9d.  in  1905,  Is.  3d. 
to  Is.  6d.  in  1909,  and  Is.  3|d.  to  Is.  7|d.  per  kilo- 
gramme in  1910.  Until  1901,  when  the  price  aver- 
aged 2s.  2id.,  the  price  had  continued  to  fall  rapidly. 
But  in  the  course  of  that  year  a  syndicate  was  formed 
by  the  Neuhausen  Co.,  the  French  works  at  Froges 
and  Salindres,  and  the  English  and  American  com- 
panies. The  syndicate  played  a  determining  part  in 
the  course  of  prices  in  the  succeeding  years  ;  and  both 
prices  and  production  increased.  It  is  possible  that 
the  advance  in  the  output  was  mostly  due  to  natural 
conditions,  but  the  price  movement  is  explained  solely 
by  the  action  of  the  combination.  The  early  years  of 
the  syndicate's  activity  proved  to  be  extremely  favour- 
able ;  the  production  developed  in  proportion  to  the 
demand,  and  the  syndicate  was  able  to  raise  the  price 
temporarily  in  1907  to  4s.  per  kilogramme.  Owing  to 
the  advance  in  price,  the  profits  of  the  companies  in- 
creased, and  raised  the  hope  that  it  would  be  of  a  last- 
ing character.  All  the  works  were  extended,  and  when 
the  Heroult  patents  expired  in  1905,  new  companies 
were  formed,  and  their  plants  were  completed  in  1907. 
The  productive  capacity  was  thereby  largely  increased, 


the  companies  individually.  The  relation  of  the  Pitts- 
burg Reduction  Co.  (the  former  name  of  the  Alu- 
minium Co  of  America)  to  the  syndicate,  was  slack 
from  the  beginning.  The  fact  that  this  company 
erected  works  in  Canada,  that  were  subsequently 
made  an  independent  undertaking,  and  was  built  for 
export  purposes  exclusively,  shows  that  there  were 
powerful  interests  in  opposition  to  the  European  pro- 
ducers. The  management  of  the  syndicate  was  not 
exercised  jointly  by  members,  but  lay  in  the  hands  of 
the  Neuhausen  Co.  The  company  owed  this  position 
to  its  great  experience  and  success  and  to  the  circum- 
stance that  it  was  the  largest  producer  in  Europe  at 
that  time;  the  company's  output  was  almost  one- 
third  of  the  world's  production,  whilst  the  two  French 
companies  were  responsible  for  20%,  and  the  English 
company  for  8% .  But  this  proportion  has  completely 
changed.  The  effort  made  to  revive  the  syndicate  in 
the  second  half  of  1909  led  to  an  improvement  in 
prices,  but  the  negotiations  were  unsuccessful.  Never- 
theless an  important  step  in  this  direction  is  recorded 
in  the  combination,  which  the  French  producers 
formed  in  November  1910,  under  the  lead  of  the 
Frankfort  Metallgesellschaft.  It  is  considered  an 
open  question  whether  the  French  organization  will 
lead  to  the  constitution  of  a  new  syndicate  to  control 
the  trade  of  the  world. 

Rhodesian  Tin. — J.  M.  Moubray,  in  the  Rhodesian 
Mining  Review  for  July  5,  gives  details  of  the  occur- 
rence of  tin  ore  in  the  Abercorn  district.  This  belt 
measures  about  ten  miles  east  and  west  by  two  miles 
wide  and  is  situated  eight  miles  south  of  the  Shamva 
gold  mine.  The  rocks  of  the  district  are  pre-Cambrian 
with  an  east  and  west  strike  and  dipping  north  at  a 


SEPTEMBER,    1911 


231 


steep  angle.  They  have  been  tilted  into  this  position 
bv  the  granite  which  is  found  immediately  to  the  south 
of  the  belt.  They  consist  of  schists,  altered  phyllites, 
banded  ironstones,  ironstone  breccias  and  conglomer- 
ates, and  limestones.  Many  acid  and  basic  dikes  have 
penetrated  the  rocks.  The  basic  dikes  are  of  no  im- 
portance from  the  point  of  view  of  the  occurrence  of 
tin  ;  they  vary  from  fine  grained  epidiorite  to  a  coarse 
diabasic  rock  consisting  almost  entirely  of  pyroxene. 
The  acid  dikes  are  of  a  pegmatite  nature  and  may  be 
divided  into  three  classes.  Those  of  the  first  division 
are  typical  pegmatite  containing  quartz  and  felspar 
in  nearly  equal  proportions,  and  as  a  rule  no  mica  ; 
no  cassiterite  has  yet  been  found  in  them.  The  second 
class  is  the  largest,  and  cassiterite  is  only  found  occa- 
sionally ;  felspar  predominates,  and  quartz  and  fine- 
grained lepidolite  mica  are  usually  present.  The 
third  class  are  composed  wholly  or  in  part  of  greisen 
formed  by  the  removal  of  the  felspar  from  the  original 
pegmatite  and  the  deposition  of  muscovite  mica  and 
cassiterite.  The  muscovite  varies  in  colour  from 
yellowish  white  to  green  and  brown.  The  cassiterite 
occurs  in  all  sizes  from  crystals  two  inches  long  to  the 
finest  grains.      Some  of  the  outcrops  of  the  dikes  have 


two  roasting  hearths  (3)  capable  of  treating  9  short 
tons  in  12  hours.  A  glowing  red  heat  is  maintained 
until  the  blue  sulphur  flames  disappear,  and  the  pyrite 
has  been  sufficiently  oxidized.  The  ore  is  then  dis- 
charged upon  cooling  floors  (4)  and  afterward  trans- 
ported to  the  hopper  (5)  from  which  it  is  raised  by  a 
cup-elevator  (6)  to  the  revolving  screen  (7).  The  first 
half  of  the  screen  is  made  of  wire  with  openings  i  in. 
square,  and  the  lower  half  of  sheet  iron  having  ^in. 
round  punched  holes.  The  two  sizes  thus  obtained 
fall  into  two  divisions  of  the  hopper  (S)  ;  the  overs  ze 
is  sent  to  rolls  (77),  and  the  ground  material  returned 
to  the  hopper  (5).  The  contents  of  the  two  divisions 
of  the  hopper  (8)  are  delivered  by  two  sets  of  magnetic 
separating  apparatus.  The  material  is  spread  upon 
travelling  belts  ( W)  w  h  ich  pass  first  under  weak  magnets 
(/7)and  then  under  stronger  ones  (72).  These  magnets 
revolve,  and  as  they  swing  round,  brass  scrapers  re- 
move the  adhering  magnetic  material.  The  first  mag- 
nets range  in  power  from  2  to  5  amperes  according  to 
the  nature  of  the  ore,  and  they  remove  all  the  free  iron 
oxide,  which  is  sent  to  the  dump  (19).  The  second 
magnets  carry  9  to  12  amperes  and  they  attract  par- 
ticles of    mixed  ore.     A  piece  of  ore  containing  one 


REMOVINQ    PYRITE   FROM   BLENDE   AT   JOPLIN. 


carried  as  much  as  20%  tin,  and  at  the  bottom  of 
shallow  prospecting  shafts  below  the  zone  of  surface 
decomposition  several  assays  of  7i%  tin  have  been 
obtained.  Mr.  Moubray  does  not  say  anything  about 
the  width  of  the  dikes  or  of  the  pay-streak.  With 
the  cassiterite  are  associated  garnet,  magnetite,  and 
occasionallv  tourmaline. 

Removing  Pyrite  from  Blende. — Lucius  L.  Wittichin 
Mines  ami  Minerals  for  August  describes  the  magnetic 
separating  plants  which  treat  practically  all  the  com- 
plex blende-pyrite  ores  of  Missouri-Kansas-Oklahoma. 
The  galena  and  blende  ores  found  in  that  district  are 
usually  free  from  iron  or  have  so  low  a  content  as  not 
to  cause  any  serious  deduction  in  price  ;  or,  we  should 
say,  the  comparatively  pure  ores  are  found  in  sufficient 
quantity  to  make  it  possible  to  postpone  the  considera- 
tion of  any  other  quality.  In  some  parts  of  the  district 
impure  ores  have  been  mined  but  left  on  the  dumps. 
Only  one  company  isconcentrating  these  complex  ores. 
This  is  the  Joplin  Separating  Co. ,  which  has  two  plants, 
one  at  Joplin  and  the  other  at  Galena,  the  latter  being 
the  larger.  The  company  does  not  own  mines  but 
buys  ore  and  dump  material  from  various  producers. 
Mr.  Wittich  describes  the  operation  of  the  plant  at 
Joplin.  The  ores  are  first  jigged  to  remove  galena  and 
gangue,  the  sizing  screen  being  shown  in  the  accom- 
panying flow-sheet  at  (/)  and  the  jigs  at  (2).  The 
blende-pyrite   concentrate  there  produced   is  sent  to 

3—6 


part  of  iron  to  50  of  blende  will  be  removed.  This 
middling  product  is  returned  to  the  jig-house  (2)  where 
it  is  treated  by  separate  apparatus.  Here  it  is  sized. 
That  which  passes  3  mm.  goes  to  the  jigs,  and  that 
passing  1  mm.  and  'i  mm.  goes  to  tables,  while  the 
oversize  is  sent  direct  to  the  rolls  (77)  and  returned  to 
the  magnetic  separators. 

Hoisting  by  Compressed  Air. — Mining  Science  for 
July  27  contains  a  brief  outline  by  Charles  Copenharve 
of  the  new  compressed-air  plant  now  being  erected  at 
Anaconda  for  hoisting  the  ore  from  the  mines.  The 
economic  problem  in  connection  with  the  installation 
of  a  new  power  plant  to  replace  steam  engines  has 
been  complicated  by  the  prejudice  on  the  part  of  the 
miners  against  electric  hoists.  The  group  of  mines 
now  managed  by  the  Anaconda  company  had  in  use 
25  steam-driven  hoists  having  a  total  horse-power  of 
40,000,  but  as  the  service  was  intermittent  probably 
not  more  than  4000  hp.  was  required  regularly.  It 
was  obvious  therefore  that  this  method  of  operating 
the  hoists  was  uneconomical.  As  the  company  has  its 
own  coal  mines  it  was  intended  at  first  to  erect  a  central 
electric  generating  station  for  the  supply  of  all  the 
power  required  for  every  purpose.  On  working  out 
the  necessary  figures  it  was  found  that  purchased 
electric  power  came  much  cheaper,  the  price  being 
^25  per  horse-power-year,  as  compared  with  $80  in  the 
old  days  of  separate  steam  units.     The  current  comes 


232 


THE    MINING    MAGAZINE 


from  the  Rainbow  falls  on  the  Missouri  river  a  few 
miles  below  Great  Falls,  Montana,  and  is  transmitted 
to  Butte,  130  miles,  at  100,000  volts.  With  the  ex- 
ception of  the  hoists,  the  whole  of  the  plant  for  under- 
ground hauling,  pumping,  etc.,  will  be  operated  elec- 
trically. The  hoists  were  excepted  partly  because  it 
-vas  supposed  that  electricity  is  not  suitable  for  deep 
mines  and  partly  on  account  of  the  prejudice  against 
it  on  the  part  of  the  miners.  Under  these  circum- 
stances it  was  deemed  best  to  operate  all  the  hoists  by 
compressed  air  supplied  from  a  central  air-compressor 
operated  electrically.  This  plant  contains  three  motors 
rated  at  1200  hp.  but  easily  capable  of  taking  1500  hp. 
Each  is  coupled  direct  to  the  ffy-wheel  of  an  air-com- 
pressor. The  air  is  compressed  to  90  lb.  and  is  de- 
livered to  a  great  equalizmg  reservoir  consisting  of 
32  receivers  each  10  ft.  diam.  by  30  ft.  high.  The 
internal  pressure  is  maintained  by  hydrostatic  water 
supplied  from  a  tank  100  ft.  diam.  and  15  ft.  high  built 
in  a  situation  above  the  receivers.  Thus  the  indi- 
vidual hoisting  plants  always  receive  their  air  at  the 
same  pressure  however  many  of  them  happen  to  be 
operating  at  the  same  time.  An  advantage  of  this 
method  of  distributing  power  is  that  the  electric  current 
consumed  is  constant  throughout  the  day.  It  is  esti- 
mated that  the  new  power  plant,  electric  and  com- 
pressed-air, will  reduce  the  cost  of  producing  copper 
by  one  cent  per  pound. 

Amalgamation  on  the  Rand. — At  the  June  meeting 
of  the  Chemical,  Metallurgical,  and  Mining  Society 
of  South  Africa,  J.  E.  Thomas  contributed  to  the  dis- 
cussion on  W.  R.  Bowling's  paper  on  this  subject,  by 
giving  the  comparative  results  at  the  Simmer  Deep- 
Jupiter  plant  before  and  after  Mr.  Dowling's  method 
was  adopted.  By  the  old  arrangement  235  stamps  had 
3351  sq.  ft.  of  amalgamating  plates  and  7  tube-mills 
with  1925  sq.  ft.  of  shaking  plates  at  a  slope  of  10%. 
By  the  new  arrangement  the  battery  plates  are  omitted 
and  1700  sq.  ft.  of  stationary  plates  placed  below  the 
tube-mills.  The  proportion  of  liquid  to  solid  in  the 
pulp  flowing  over  the  tube-mill  plates  has  been  de- 
creased from  2  :  1  to  11 : 1,  the  aperture  of  the  battery 
screen  increased  from  0  0461  in.  to  0'0685in.,  the  num- 
ber of  stamps  decreased  from  235  to  220,  the  number 
of  tube-mills  increased  from  7  to  10,  and  the  tonnage 
per  24  hours  increased  from  2125  to  2243.  The  ex- 
traction by  amalgamation  was  56' 8%  by  the  old  method, 
and  55  52%  by  the  new,  and  the  total  extraction  9338% 
by  the  old  and  94  23%  by  the  new.  Careful  examina- 
tion revealed  no  amalgam  in  the  cyanide  pulp. 

Charcoal  in  Cyanide  Tailing. — In  the  Monthly 
Journal  of  the  West  Australian  Chamber  of  Mines 
for  June,  V.  T.  Edquist  gives  an  account  of  the  method 
of  re-treating  cyanide  slime  from  the  Great  Boulder 
Perseverance  at  Kalgoorlie.  This  slime  was  originally 
produced  at  the  mine  by  dry-crushing,  and  it  was 
transported  thence  to  Lakeside,  three  miles  away,  for 
cyanide  treatment.  The  filter-press  residue  was  moist 
and  sticky  and  would  not  readily  discharge  from  the 
cars,  so  the  inside  of  these  was  sprinkled  with  wood- 
ashes.  In  consequence  of  this,  the  tailing  heaps  con- 
tain large  amounts  of  charcoal  which  has  precipitated 
much  of  the  gold  left  in  the  solution  or  subsequently 
dissolved  by  it.  When  it  was  decided  to  re-treat  the 
dumps  which  average  2 J  dwt.  gold,  it  soon  became 
obvious  that  the  charcoal  must  be  separated  and 
treated  separately.  The  dump  material  after  being 
sent  to  mixers,  is  passed  through  a  trommel  with  -^^  in. 
holes.  The  larger  portions  of  charcoal  and  other  vege- 
table matter  are  here  caught  together  with  any  nodules 
of  slime  that  have  not  been  disintegrated.  This  is  all 
sent  again  to  a  mixer  with  an  excess  of  water  so  that 


the  nodules  may  have  another  chance  of  being  broken. 
The  final  charcoal  product,  obtained  after  a  second 
screening,  contains  from  20  to  40  oz.  gold  per  ton. 
The  finer  charcoal  that  passes  the  trommels  flows  to 
the  vats  and  floats  during  agitation,  and  it  is  removed 
by  hand-skimming.  The  mixed  coarse  and  fine  char- 
coal products  are  burnt  and  the  leavings  sold  to  smel- 
ters. The  amount  of  gold  thus  recovered  averages 
5  grains  or  8d.  per  ton  of  slime.  Associated  with  it 
is  about  3%  of  silver,  as  compared  with  18%  of  silver 
obtained  with  the  gold  extracted  from  the  slime  by 
cyanide. 

Modified  Square-Set. — In  the  June  Proceedings  of 
the  Australasian  Institute  of  Mining  Engineers  there  is 
an  interesting  paper  by  A.  J.  Moore  advocating  the 
adoption  of  a  modified  form  of  square-set,  which  he 
might  call  a  triangle-set.  He  points  out  that  the  or- 
dinary square-set  as  used  nowadays  is  only  a  scaffold- 
ing and  does  not  help  very  much  to  support  the  walls. 
When  originally  introduced  by  Deidesheimer  for  min- 
ing the  large  lodes  at  the  Comstock,  it  had  the  ele- 
ments of  strength  in  its  construction  in  the  wall-plates 
and  the  diagonals.  These  were  gradually  discarded  in 
order  to  reduce  expense,  and  safety  was  ensured  in- 
stead by  resorting  to  filling  the  exhausted  stopes  with 
waste  as  soon  as  possible.  Broken  Hill  provides  a  good 
example  of  this  application  of  the  method.  Mr.  Moore 
founds  his  criticisms  of  the  square-set  on  Broken  Hill 
practice.  Though  his  paper  contains  only  a  proposi- 
tion and  not  a  record  of  practice,  it  is  of  interest  to  the 
mining  engineer  and  should  arouse  discussion.  We 
reproduce  here  a  diagrammatic  cross  section  of  a  lode 
showing  the  system  (Fig.  1),  an  enlarged  view  of  the 
timbering  (Fig.  2),  details  of  the  joint  (Fig.  3),  and  the 
drift  set  (Fig.  4).  The  method  is  to  make  the  timber- 
ing in  the  planes  at  right  anglesto  the  lode  in  triangular 
set  and  to  space  these  apart  by  struts  parallel  with  each 
other.  The  triangulated  frames  (Figs.  1  and  2)  are  cal- 
culated to  bear  the  pressure  of  the  wall  and  back,  while 
the  struts  do  not  have  to  bear  much  pressure,  only 
serving  to  hold  the  frames  in  place.  Any  portion  (A/) 
of  the  rock  (Fig.  1)  coming  against  a  joint  will  be  sup- 
ported by  the  line  of  caps  (AC)  and  the  line  of  posts 
{AB).  If  any  link,  say  the  cap  {inn),  fails,  the  pres- 
sure along  {Am)  will  be  split  along  [mp)  and  {mq). 
At  (p)  and  (q)  there  are  three  members  that  can  take 
up  the  pressure,  and  eventually  the  whole  structure 
will  assume  some  part  of  the  stress.  Similarly  when 
an  isolated  weight  from  the  back  comes  on  a  joint 
every  member  of  the  structure  shares  the  stress.  It 
will  be  seen  that  unexpected  and  irregular  pressures 
are  not  likely  to  upset  the  timbering  as  in  the  case  of 
the  square  set,  and  the  timbers  need  not  be  so  massive 
at  the  joints  in  order  to  secure  stability.  The  caps  and 
struts  could  be  made  of  timbers  10  by  8  in.  and  the 
diagonal  posts  of  10  by  6  in.  timbers  all  with  their 
widest  sides  downwards.  The  inclination  of  the 
diagonal  posts  would  depend  to  some  extent  on  the 
dip  of  the  lode  ;  in  the  illustration  it  is  65^  with  the 
horizontal.  The  distance  vertically  between  the  centre 
lines  of  the  caps  is  8  ft.  and  the  length  of  the  caps  is 
7  ft.  6  in.  The  frames  are  5  or  even  6  ft.  apart.  For 
a  drift-set  two  diagonals  would  be  removed  and  10  by 
10  in.  uprights  would  be  placed  under  each  end  of  the 
cap,  and  similar  timbers  would  be  used  for  reinforcing 
the  other  diagonals  in  the  manner  shown  in  Fig.  4. 
As  regards  the  joints  (Fig.  3),  the  caps  butt  against 
each  other  by  tenons  5  by  5  by  3j  in.  ;  the  strut  tenons 
are  7  by  5  by  2|  in.  and  the  diagonals  are  bevelled  by 
1^  in.  The  caps  ha\e  a  bearing  surface  of  2  in.  on  the 
diagonals  the  full  width  in  addition  to  the  tenon. 
These  joints  will  be  more  expensive  to  cut  than  those 


SEPTEMBER,    1911 


233 


of  the  square-set,  but  on  the  other  hand  they  are  much 
stronger.  An  advantage  is  that  the  total  amount  of 
timber  used  is  not  greater,  and  each  member  is  Hghter 
and  easier  to  handle.  In  many  cases  waste-filling  will 
not  be  required  at  all,  and  in  any  case  it  will  not  be 
necessary  to  fill  so  regularly  or  so  often.  The  drift- 
set  is  much  stronger,  and  chutes  can  be  put  in  more 
easily.  There  is  a  greater  proportion  of  the  timber  in 
the  frames  across  the  lode. 


Chalcocite  as  a  Primary  Mineral. — In  Economic 
Geology  for  June,  F.  B.  Laney  describes  the  copper 
ore  deposits  of  the  Virgilina  district  which  is  situated 
on  the  borders  of  North  Carolina  and  Virginia.  The 
sulphide  ores  consist  of  bornite  and  chalcocite,  with 
only  microscopic  traces  of  chalcopyrite.  The  level  of 
the  ground  water  is  from  50  to  75  ft.  below  the  sur- 
face, and  the  zone  of  secondary  alteration  does  not  go 
below  250  ft.     The  chief  mines  are  down  from  350  to 


\  \/////////////////M 


Sintering  Iron  Ores. — In  the  Bulletin  of  the  Ameri- 
can Institute  of  Mining  Engineers,  James  Gayley  con- 
tributes a  paper  on  the  sintering  of  iron  ores  by  the 
Dwight-Lloyd  straight-line  or  '  conveyor  '  machine. 
As  we  gave  an  illustrated  account  of  this  invention  in 
our  issue  of  August  1910,  it  is  not  necessary  to  re- 
capitulate details  of  the  plant  and  process  on  this 
occasion.  Suffice  it  to  say  that  the  sintering  flame  is 
drawn  down  upon  and  through  thin  layers  of  fine  ore 
by  means  of  a  suction  pipe  below  the  series  of  travel- 
ling receptacles  containing  them.  The  process  has 
been  successful  in  connection  with  lead,  copper,  and 
other  sulphides,  and  it  has  attracted  the  notice  of  iron 
metallurgists,  who  have  long  been  seeking  a  means  of 
agglomerating  flue-dust,  fine  ore,  and  magnetic  con- 
centrate. Many  processes  have  been  proposed  and 
adopted,  such  as  nodulizing  and  briquetting,  but  none 
of  these  give  perfect  results  ;  in  all  cases  the  lumps  if 
strong  enough  to  stand  the  burden  of  the  blast-furnace 
are  difficult  to  smelt.  Experiments  with  the  Dwight- 
Lloyd  machine  show  that  the  product  is  cellular  and 
coherent,  in  fact  in  ideal  condition  for  blast-furnace 
requirements.  Fine  iron  ore,  except  flue-dust,  con- 
tains no  combustible  constituent  as  is  the  case  with 
sulphides,  so  it  is  necessary  to  add  about  7%  of  coal 
to  the  charge.  Mr.  Gayley  gives  much  information 
as  to  the  working  of  the  machine  and  quotes  the  re- 
sults obtained  in  a  number  of  cases. 


^^^^ 


500  ft.  and  at  the  deepest  points  there  is  as  much 
chalcocite  as  bornite.  In  the  upper  levels  the  rela- 
tion of  the  two  minerals  is  such  that  a  large  part  of 
the  chalcocite  may  be  taken  to  be  secondary  and  more 
recent  than  the  bornite,  but  in  the  lowest  levels  the 
two  minerals  are  so  intimately  intergrown  that  the 
only  conclusion  possible  is  that  they  are  genetically 


234 


THE    MINING    MAGAZINE 


contemporaneous.  As  chalcocite  is  usually  regarded 
as  a  mineral  of  secondary  origin,  the  Virgilina  de- 
posit is  of  special  interest  to  economic  geologists.  Mr. 
Laney  gives  a  complete  account  of  the  geology  of  the 
district  and  of  the  mineral  constituents  of  the  veins, 
with  excellent  micrographic  pictures  showing  the  in- 
timate disposition  of  the  minerals. 

Cyaniding  Ohinemuri  River  Sand. — In  our  issue  of 
September  1910,  Arthur  Jarman  gave  an  account  of 
the  blocking  of  the  river  Ohinemuri  by  the  tailing 
discharged  into  it  by  the  Waihi  and  other  gold  mines 
in  the  Thames  mining  district.  New  Zealand.  He 
mentioned  that  a  company,  the  Waihi-Paeroa  Gold 
Extraction  Co.,  was  being  formed  for  the  removal  of 
the  sand  that  has  accumulated  in  the  river  bed  and  for 
its  treatment  by  re-grinding  and  cyanidation.  In  the 
June  Proceedings  of  the  Australasian  Institute  of 
Mining  Engineers,  Robert  M.  Aitken  describes  this 
scheme  in  detail.  Up  to  the  end  of  1900,  the  total 
amount  of  tailing  discharged  into  the  river  was  about 
500,000  tons.  Since  then  the  output  of  the  mines  has 
greatly  increased,  until  now  the  yearly  tonnage  is 
nearly  600,000.  Probably  the  total  output  to  the  end 
of  1910  was  5  million  tons.  It  is  only  recently  that 
fine  grinding  and  extraction  of  the  contents  of  the 
sand  residue  have  been  adopted,  so  that  the  average 
value  of  the  tailing  accumulated  in  the  river  is  suffi- 
ciently high  to  make  its  re-treatment  a  profitable 
proposition 

The  Ohinemuri  is  a  small  river  having  a  fall  of  JO  ft. 
per  mile  over  the  stretch  of  10  miles  from  the  Waihi 
to  the  Talisman  and  Crown  mines.  The  tailing  does 
not  deposit  to  any  great  extent  along  this  part  of  its 
course,  but  the  river  afterwards  debouches  into  flat 
lands  on  which  the  town  of  Paeroa  stands.  This 
tract  forms  an  excellent  settling  basin  for  the  sand- 
tailing.  The  river  is  tidal  and  it  is  full  of  vegetable 
growth.  The  flow  is  just  sufficient  to  carry  away  the 
slime,  from  which  the  gold  has  been  extracted,  but 
allows  the  sand  to  settle.  So  great  is  the  accumula- 
tion that  for  four  miles  the  average  depth  of  the  water 
has  been  reduced  from  20  ft.  to  as  many  inches.  The 
deposit  has  been  carefully  sampled  by  drilling.  The 
finer  sand  near  the  banks  averages  Ss.  4d.  per  ton,  of 
which  6s.  Id.  is  gold  and  2s.  3d.  silver,  and  the  coarser 
sand  in  the  bed  gives  from  8s.  4d.  to  10s.  gold,  and 
2s.  lOd.  to  3s.  4d.  silver.  A  plant  for  treating  the 
deposit  is  being  built  2  miles  below  Paeroa,  and  the 
method  of  extraction  closely  follows  that  now  in  use  at 
the  Waihi  and  the  Grand  Junction.  Twenty  tube-mills 
will  each  reduce  25  tons  per  day  to  pass  200  mesh, 
and  cyanide  solution  will  be  used  in  them.  Subse- 
quently the  slime  will  be  treated  in  Brown  agitators 
(Pachuca  vats)  and  the  solution  extracted  in  filters  of 
the  Moore  submerged  type.  An  important  point  that 
arose  was  the  loss  of  gold  and  silver  due  to  the  pres- 
ence of  charcoal  which  had  been  dumped  into  the 
river  by  the  power  stations  of  the  various  mines.  The 
sand  has  therefore  to  be  preliminarily  screened  before 
going  to  the  tube-mills  and  also  sent  over  '  Union  ' 
vanners,  which  not  only  separate  the  smaller  portions 
of  vegetable  matter  but  remove  some  of  the  barren 
sand.  The  charcoal  so  caught  contains  gold  so  it  is 
burnt  and  the  residue  smelted. 

As  regards  the  method  of  collecting  the  sand  from 
the  river,  the  author  and  P.  N.  Kingswell,  after  much 
experiment,  decided  to  use  an  air-lift  dredge.  The 
air-lift  is  a  telescopic  10  in.  pipe  with  a  delivery  chute 
at  the  top  ;  the  compressed-air  escapes  upward  from 
a  pipe  at  the  bottom,  and  a  number  of  water  jets 
driven  by  a  centrifugal  pump,  and  easily  controlled, 
play  round  the  bottom  edges  for  the  purpose  of  loosen- 


ing the  sand  and  of  making  the  upward  current  con- 
tain equal  volumes  of  water  and  sand.  The  air  pres- 
sure is  sufficient  to  raise  this  mixture  4  ft.  above  water 
level.  The  mixture  discharges  into  belt  bucket-eleva- 
tors which  carry  it  to  barges.  When  full  the  barges 
are  towed  by  oil  launches  to  the  treatment  plant, 
where  the  sand  is  removed  by  similar  elevators,  and 
after  screening  discharged  into  ferro-concrete  storage 
reservoirs. 

CURRENT    LITERATURE 

Electric  Winding.  —  The  Journal  of  the  South 
African  Institute  of  Engineers  for  June  contains  a 
paper  by  T.  P.  E.  Butt  on  the  new  electric  plant  at 
the  Randfontein  Central  mine,  with  special  reference 
to  the  electric  winding  engines.  The  paper  is  lengthy 
and  full  of  useful  details  and  drawings. 

Prevention  of  Overwinding. — The  Iron  and  Coal 
Trades  Review  for  .\ugust  4  describes  Dalglish's  ap- 
paratus for  the  prevention  of  overwinding  in  mine- 
hoists. 

Laying  Dust. — At  the  meeting  of  the  North  of  Eng- 
land Institute  of  Mining  and  Mechanical  Engineers 
held  in  August,  W.  M.  Thornton  read  a  paper  detail- 
ing experiments  with  soap,  oil,  and  other  solutions 
and  emulsions,  undertaken  to  ascertain  their  efficiency 
in  keeping  mine  dust  wet  or  of  binding  it  into  larger 
pieces 

Drill  for  Deep  Holes. — The  Mining  and  Scientific 
Press  for  July  29  contains  an  article  by  G.  H.  Oilman 
describing  a  new  drill  for  deep  holes,  invented  by 
C.  H.  Locher,  that  is  claimed  to  overcome  the  diffi- 
culty of  cleaning  the  holes  made  by  drills  of  the  churn 
type. 

Cost  Records. — In  the  Proceedings  of  the  Austra- 
lasian Institute  of  Engineers  for  June,  T.  H.  Palmer 
&  R.  Rossdescribe  the  method  of  keeping  the  record  of 
costs  at  the  Broken  Hill  Junction  North  mine. 

Modder  B.  Equipment. — The  South  African  Min- 
ing Jour)ial  for  August  5  contains  a  description  of 
the  Modderfontein  B  surface  equipment.  We  gave  an 
outline  of  the  metallurgical  method  adopted  in  our 
February  issue. 

Earth  Dams. — In  the  Bulletin  of  the  Mexican  In- 
stitute of  Mining  and  Metallurgy,  No.  3,  1911,  John 
M.  Nicol  describes  the  building  of  dams  filled  with 
earth  that  has  been  transported  hydraulically.  He 
criticizes  the  construction  of  the  first  Necaxa  dam 
which  failed  two  years  ago. 

Crane's  Ore  Washer. — In  the  Engineering  and 
Mining  Journal  for  July  22,  H.  M.  Adkinson  refers 
to  the  advantages  to  be  gained  by  careful  hand-sorting 
of  ore,  and  describes  the  combined  trommel  and 
washer  invented  by  F.  J.  Crane  for  eliminating  the 
finer  ore  and  washing  the  coarse  ore  that  is  to  be 
picked. 

Concentration  of  Tungsten  Ores. — In  Metallur- 
gical and  Chemical  Engineering  for  August,  H.  C. 
I'armelee  continues  his  study  of  methods  of  concen- 
trating tungsten  ores  and  old  dumps,  especially  in  con- 
nection with  Colorado  practice. 

Dredging  in  Colombia. — In  the  Mining  and  Scien- 
tific Press  for  July  22,  Charles  Janin  writes  on  gold 
dredging  in  Colombia,  more  particularly  describing 
the  operations  on  the  Cauca  and  Nechi  rivers. 

Geology  of  Oil  Deposits. — Economic  Geology  for 
June  contains  a  paper  by  M.  R.  Campbell,  giving  a 
historical  review  of  the  various  theories  advanced  by 
American  geologists  relating  to  the  origin  and  accu- 
mulation of  oil. 


SEPTEMBER,    1911 


235 


Literature  of  Ore  Deposits.— Economic  Geology 
for  June  contains  an  article  by  F.  L.  Ransome  re- 
viewing the  literature  relating  to  ore  deposits  pub- 
lished in  1910. 

Titanium  Ores. — The  Bulletin  of  the  Imperial  In- 
stitute, No.  2,  1911,  contains  an  article  giving  aresume 
of  information  relating  to  the  distribution  and  uses  of 
titanium  ores. 

Philippine  Islands. — The  Mining  and  Scientific 
Press  for  July  8  contains  an  article  by  Warren  D. 
Smith  on  the  economic  geology  of  the  Philippine 
Islands. 

Iron  Resources  of  Canada. — A.  B.  Willmott  con- 
tributes a  paper  to  the  Quarterly  Bulletin  of  the 
Canadian  Mining  Institute  for  April  on  the  iron  ore 
resources  of  Canada. 

Bolivian  Tin  Deposits. — In  the  Engineering  and 
Mining  Journal  for  August  19,  Miltiades  Armas, 
formerly  manager  for  the  La  Paz  Mining  Co.,  gives 
a  geological  description  of  tin  ore  deposits  in  Bolivia. 
South  African  Tin. — The  South  African  Mining 
Journal  for  August  5  contains  articles  on  Swaziland 
tin  gravels,  on  the  Government  geologists'  latest  re- 
port in  the  Waterberg  tin  district,  and  on  the  Nyls- 
troom  tin  mine. 

Zaaiplaats  Tin.  —  The  South  African  Mining 
Journal  for  July  22  contains  Hans  Merensky's  report 
on  the  Zaaiplaats  tin  deposits  in  the  Waterberg  dis- 
trict of  the  Transvaal.  Hitherto  it  has  been  supposed 
that  the  ore  was  confined  to  pipes  of  limited  extent, 
but  recent  observations  lead  Mr.  Merensky  to  the 
opinion  that  the  pipes  are  shoots  from  main  lodes  and 
he  is  recommending  that  work  shall  be  done  on  a 
larger  scale  and  the  metallurgical  plant  extended. 

Wolfram  in  Queensland.  —  The  Queensland 
Government  Mining  Journal  for  July  describes  the 
Mount  Carbine  wolfram  district,  with  special  reference 
to  the  concentration  plant  erected  by  the  Irvinebank 
company. 

Thorium  Minerals. — The  Bulletin  of  the  Imperial 
Institute,  No.  2,  1911,  contains  two  notes  on  ores 
containing  thorium ;  one  describes  several  alluvial 
concentrates  obtained  in  the  Federated  Malay  States 
containing  cassiterite,  ilmenite,  and  thorium  and  cerium 
oxides,  and  the  other  some  monazite  sand  from  Tra- 
vancore,  India. 

Artificial  Covellite. — In  the  Columbia  School  of 
Mines  Quarterly  for  July,  Austin  F.  Rogers  describes 
many  occurrences  of  covellite  which  are  apparently 
replacements  of  sphalerite,  and  he  describes  experi- 
ments whereby  covellite  can  be  formed  by  acting  on 
sphalerite  with  copper  sulphate  solution. 

Pachuca  Vats.  —  In  the  August  Bulletin  of  the 
American  Institute  of  Mining  Engineers,  Huntington 
Adams  describes  the  continuous  method  of  operating 
Brown  agitators,  otherwise  Pachuca  vats,  at  the 
Natividad  mine,  Oaxaca,  Mexico. 

Electroplating  Battery  Plates. — In  the  Milling  and 
Scientific  Press  for  July  29,  J.  D.  Hubbard  describes 
the  electrolytic  apparatus  used  at  the  Oriental  Con- 
solidated Co.'s  mines  in  Korea  for  coating  amalgama- 
tion plates  with  silver,  and  discusses  many  practical 
details  in  connection  with  the  use  of  silver-coated 
plates. 

Parting  Bullion. — The  Brass  World  for  June  de- 
scribes a  method  for  parting  platinum-gold-silver 
bullion. 

Reid's  Method  of  Smelting. — The  Mining  and  En- 
gineering World  (Chicago)  for  July  1  has  an  article 
on  the  electric  smelting  furnace  patented  by  J.  H. 
Reid  of  Philadelphia.     It  is  stated  to  be  applicable  to 


the  treatment  of  complex  sulphides  containing  precious 
metals.  The  process  has  been  much  advertised  but 
the  technical  details  are  incomplete. 

Roasting  Nickel-Copper  Matte.  —  The  Columbia 
School  of  Mines  Quarterly  {or  July  contains  a  paper  by 
E.  F.  Kern  and  H.  W.  Walter  describing  investigations 
made  in  the  metallurgical  laboratory  of  the  School  of 
Mines  with  a  view  of  obtaining  information  as  to  the 
chemical  reactions  involved  in  the  process  of  roasting 
nickel-copper  matte.  This  is  a  branch  of  metallurgy 
that  is  kept  secret  by  the  smelters. 

Horwood's  Sulphatizing  Process. —  In  the  June 
Proceedings  of  the  Australasian  Institute  of  Mining 
Engineers,  E.  J.  Horwood  describes  the  possible 
applications  of  his  process  for  sulphatizing  the  galena 
and  oxidizing  the  pyrite  constituents  of  complex  sul- 
phide slime,  leaving  the  blende  unaltered.  By  this 
method  the  slime  may  be  treated  by  flotation  and  the 
blende  recovered.  Donald  Clark  described  this  pro- 
cess in  our  issue  of  January  1910,  and  Mr.  Horwood's 
paper  gives  further  details  of  experimental  results. 

Copper  Smelting  at  Lake  Superior. — In  the  Colum- 
bia School  of  Mines  Quarterly  for  July,  Henry  D. 
Conant  gives  an  outline  of  the  methods  of  smelting  in 
use  in  the  Lake  Superior  copper  district. 

Electrolytic  Refining.  —  In  Metallurgical  and 
Cheititcal  Engineering  for  August,  E.  F.  Kern  con- 
tributes a  paper  on  the  constitution  of  anode  sludge 
and  describes  the  various  methods  employed  for  ex- 
tracting the  metallic  contents. 

Zinc  Metallurgy. — The  Mining  and  Engineering 
World  (Chicago)  for  August  12  contains  a  description 
of  the  Louvrier-Louis  furnace  for  distilling  zinc  ores. 
This  furnace  has  been  used  in  France  and  Spain  in 
connection  with  steel,  ferro-silicon,  and  calcium  car- 
bide, and  has  only  recently  been  applied  experiment- 
ally to  zinc  ores. 

Roasting  Furnaces. — In  Revue  de  Metallurgie  for 
August,  Leon  Guillet  contributes  a  lengthy  article  re- 
viewing recent  progress  in  the  roasting  of  sulphide 
ores. 

Determination  of  Copper  by  Iodide  Method. — In 
the  Mining  and  Scientific  Press  for  July  8,  L.  D. 
McClure  describes  his  method  of  carrying  out  the 
iodide  determination  of  copper  in  ores,  that  he  has 
used  for  some  time  on  the  samples  at  the  Live  Oak 
property,  Arizona.  He  finds  it  more  rapid  than  the 
permanganate  and  electrolytic  methods,  and  depend- 
able within  narrow  limits  of  error. 

Analysis  of  Tungsten  Ores. — In  Metallurgical  and 
Chemical  Engineering  for  August,  Hugh  F.  Watts 
reviews  several  methods  of  analysing  tungsten  ores. 

Cost  of  Producing  Oil. — In  the  Mining  and  Scien- 
tific Press  for  July  8,  W.  R.  Jewell  discusses  the 
various  factors  in  the  cost  of  producing  oil. 

Transvaal  Coal.— At  the  June  meeting  of  the 
Chemical,  Metallurgical,  and  Mining  Society  of  South 
Africa,  M.  Thornton  Murray  read  a  paper  describing 
his  tests  of  the  calorific  value  of  Transvaal  coals. 

Earthquakes  in  Mines.— The  Quarterly  Bulletin 
of  the  Canadian  Mining  Institute  for  April  contains  a 
paper  by  James  Douglas  giving  reminiscences  of  the 
effects  of  earthquakes  in  mines.  He  is  installing 
seismographs  in  the  copper  mines  with  which  he  is 
connected  in  Arizona  with  the  object  of  studymg 
earthquake  effects  at  depth. 

Copies  of  the  original  papers  and  articles  men- 
tioned under  '  Precis  of  Technology  'and  '  Current 
Literature  '  can  be  supplied  on  application  to  The 
Mining  Magazine. 


236 


THE    MINING    MAGAZINE 


BOOKS  REVIEWED 

Metallurgy  of  Tin.  By  Henry  Louis.  Cloth, 
octavo,  140  pages,  with  many  illustrations.  New 
York  :  McGraw-Hill  Book  Co.  Price  8s.  6d.  For 
sale  by  The  Mining  Magazine. 
Of  all  branches  of  metallurgy  the  smelting  of  tin 
ores  is  at  the  present  time  the  most  secret.  Those 
who  by  labour  and  experience  have  mastered  the  in- 
tricacies of  the  art  are  still  able  to  adhere  to  the  ancient 
order  of  things  and  keep  their  knowledge  to  themselves. 
The  terms  and  conditions  on  which  tin  ores  are  bought 
and  sold  are  sufficiently  favourable  to  the  mine-owners 
to  make  it  not  worth  their  while  to  re-invent  the  metal- 
lurgy for  themselves.  There  are  no  gold  and  silver 
contents  in  tin  ore  and  concentrate  to  provide  the 
smelters  with  inordinate  profits,  as  was  the  case  in  the 
palmy  days  of  the  Swansea  copper  business.  Though 
sellers  of  tin  ores  grumble  occasionally  at  the  alleged 
onerous  terms  of  the  smelters,  their  grievance  is  com- 
paratively small.  After  all,  why  should  a  buyer 
possessing  special  technical  knowledge  which  is  his 
stock-in-trade  and  goodwill,  tell  the  seller  how  to  do 
it  himself  ?  If  an  American  company  possessed  a  tin 
mine  in  Dakotah  or  Durango,  having  a  yearly  output 
of  a  million  tons  of  6%  ore  and  smelted  it  on  the  spot, 
we  should  in  no  time  have  a  generous  literature  on  the 
metallurgy  of  the  metal  ;  but  not  till  then.  At  present 
the  smelters  in  the  Straits,  Queensland,  Cornwall,  and 
Hamburg  alone  have  the  knowledge  how  to  combat 
the  affinity  of  tin  for  silica,  and  how  to  deal  with  the 
multitudinous  impurities  usually  found  in  association, 
such  as  iron,  wolfram,  titanium,  etc.  The  straight 
tin-smelting  reaction  is  simple  enough,  and  if  ore  and 
labour  is  plentiful  a  crude  furnace  and  process  will  be 
profitable  though  much  metal  is  lost  in  the  slag.  Such 
operations  are  conducted  in  China,  the  Malay  penin- 
sula, and  in  South  America,  but  they  cannot  be  ranked 
as  metallurgy  in  its  modern  meaning,  nor  are  they  of 
great  help  to  the  student  who  desires  to  equip  him- 
self for  a  practical  campaign. 

It  stands  to  reason  that  any  book  on  the  metallurgy 
of  tin  must  be  (to  quote  the  stereotyped  newspaper  pro- 
verb) like  the  play  of  Hamlet  with  the  part  of  the 
Prince  of  Denmark  omitted.  Mr.  Louis  has  done  the 
best  he  can  with  the  means  at  his  disposal.  Though 
not  having  experience  in  modern  works,  he  spent  some 
years  of  his  earlier  life  in  the  Malay  peninsula  and 
studied  the  native  methods  of  treating  the  ores,  so  that 
his  book  has  parts  of  personal  interest.  He  has  also 
collected  together  nearly  every  available  item  of  pub- 
lished information.  The  greater  part  of  the  book 
originally  appeared  as  a  chapter  of  '  The  Mineral  In- 
dustry, '  Vol.  5,  published  in  1897,  and  this  volume  was 
in  demand  after  the  other  contents  had  lost  their  general 
interest.  Mr.  Louis  wastherefore  induced  to  reprintthe 
article  in  book  form,  with  as  much  additional  matter  as 
possible.  The  work  is  by  no  means  authoritative  ; 
naturally,  owing  to  the  lack  of  first-hand  information 
except  from  Malaya,  this  cannot  be  expected.  There 
are  indeed  many  parts  where  additional  or  corrobora- 
tive information  is  desirable,  and  could  be  given  by 
people  with  special  knowledge  without  any  detriment 
to  their  own  interests.  For  instance,  the  statement 
that  the  Bolivian  concentrates  smelted  in  Cornwall  are 
richer  than  those  produced  locally  is  open  to  question. 
The  author  is  inaccurate  in  his  names  ;  "  Levey  "  and 
"Nicholaus"  may  be  pardonable,  but  it  is  discon- 
certing to  find  the  chief  German  smelting  firm  given 
as  "  Robinson  &Bense"  and  our  good  friend  George  T. 
masquerading  as  "  M.  J.  T.  Holloway." 


Metallurgie  des  Zinns.  By  Hans  Mennicke. 
Octavo,  196  pages,  and  40  illustrations.  Halle, 
Germany  :  Wilhelm  Knapp.  Price  10  marks. 
This  book  is  one  of  a  series  of  monographs  on  ap- 
plied electro-chemistry  issued  by  the  publishing  house 
of  Knapp  of  Halle.  As  we  have  already  said  in  re- 
viewing Mr.  Louis'  book,  the  literature  relating  to  the 
metallurgy  of  tin  is  scanty.  The  present  book  does 
not  tell  us  quite  as  much  as  some  others.  On  the 
other  hand  it  describes  in  detail  many  of  the  side  sub- 
jects, and  the  parts  dealing  with  the  recovery  of  tin 
from  scrap,  dross,  and  other  waste  material  contain 
plenty  of  useful  information.  The  chapter  on  the  re- 
fining of  low  quality  tin  by  chemical  and  electrolytic 
methods  is  also  good. 

Technical  Dictionary  in  Six  Languages.  Edited 
by  Deinhardtand  Schlomann      Vol.  XI,  Metallurgy 
of  Iron  ;  compiled  by  William  Venator  and  Colin 
Ross.     Cloth,  800  pages,  illustrated.     Munich:   R. 
Oldenbourg  ;    London  :    Constable  &    Co.      Price 
10s.  6d.     For  sale  by  The  Mining  Magazine. 
We  have  already  reviewed  several  volumes  of  this 
series  of  technological  dictionaries  which  covers  the 
German,  English,French,Russian,Italian,  and  Spanish 
languages.  Nobody  appreciates  the  enormous  difficulty 
of  producing  a  dictionary  of  this  sort  until  he  has  tried 
to  do  it,  so  criticism  should  be  kindly.     These  books 
are  essentially  German,  and  the  words  or  phrases  in 
the  other  languages  are  not  always  indigenous,  but  are 
often  the  literal  translation  of  the  technical  German. 
For  instance,  the  German  chemist  has  a  word  '  chloren- 
twicklungs  flasche,'  which  means  a  glass  apparatus 
used  in  producing  chlorine  for  laboratory  purposes  ; 
the  dictionary  calls  it  a  "chlorine  developing  appar- 
atus."    Englishmen  are  often  taunted  with  their  lack 
of  enterprise  as  regards  the  study  of  foreign  languages, 
and  are  told  that  for  every  Englishman  that    learns 
German  there  are  a  hundred  or  even  more  Germans 
that  learn  English.     On  glancing    through  the  won- 
derful words  such  as  '  Kapselhochdruckgeblase,'  '  um- 
fanggesschwindigkeit,'  and  '  gaszufuhrungskapilare,' 
we  cannot  help  thinking  that  the  inclination  or  other- 
wise to  learn  each  language  is  an  exhibition  of  common 
sense  on  the  part  of  both  nations. 

The  present  volume  covers  the  metallurgy  of  iron 
and  a  number  of  cognate  subjects.     The  bulk  of  the 
book  is  occupied  by  words  and  phrases  connected  with 
the  foundry,  blast-furnace  practice,  and  the  manu- 
facture of  wrought-iron   and  steel.     Over   100  pages 
are  occupied  with  laboratory  work  and  metallography. 
Other  chapters  are  devoted  to  machinery  used  in  these 
industries,  fuel,  fluxes,  the  dressing  of  iron   ores,  ore 
deposits,  and  minerals.     The  elucidation  of  the  mean- 
ing of  the  words  is  helped  by  little  diagrammatical 
drawings  which  often  serve  as  useful  indicators. 
Mining  Law  for  the  Prospector,  Miner,  and 
Engineer.     By  H.  W.  MacFarren.     Limp  cloth, 
small  octavo  ;   356  pages,   with  illustrations.      San 
Francisco  :    Mining  and   Scientific   Press  ;    Lon- 
don :   The  Mining  Magazine.     Price  8s   6d. 
This  book  as  its  title  indicates  is  intended  for  the 
practical  miner,  and  not  for  the  lawyer  who  is  already 
supplied  with  a  number  of  works  adapted  to  his  par- 
ticular requirements.      Mr.  MacFarren 's  book  should 
be  of  great  value  in  the  United  States  as  it  fills  a  want 
that  has  been  long  felt. 

Mineral   Resources  of   Wyoming.     By   C.    E. 

Jamison,    State   Geologist.     Pamphlet,   102  pages. 

Cheyenne,  W^yoming  ;   S.  A.  Bristol  Co. 

This  is  a  bulletin  published  by  the  State  of  Wyoming 

and  is  useful  because  it  contains  the  mining  laws  of 

that  State. 


SEPTEMBER,    1911 


237 


COMPANY   REPORTS 

Dolcoath. — The  elasticity  of  the  premier  tin  mine  of 
Cornwall  is  once  more  evidenced  by  the  report  for  the 
half-year  ended  June  30  now  issued  The  underground 
work  in  connection  with  the  new  Williams  shaft,  and 
the  substitution  of  Holman  air-cushion  or  '  pneumatic  ' 
stamps  for  the  battery  of  old  Cornish  stamps,  have 
made  it  necessary  to  reduce  the  amount  of  ore  mined 
and  milled.  To  make  up  the  deficiency,  it  has  been 
possible  to  raise  ore  of  higher  grade,  and  this  fact,  to- 
gether with  the  advance  in  the  price  of  tin,  has  had 


cage  roads  are  completed  at  the  Williams  shaft,  and 
the  electric  hoisting  engines  and  the  electric  pumps 
are  being  erected.  It  is  expected  that  the  shaft  will 
be  ready  for  operation  by  the  end  of  September.  An 
interesting  item  in  the  report  is  the  announcement  that 
the  zinc-copper  and  copper-tin  deposits  in  the  Killas 
Shaft  and  Stray  Park  sections  are  being  actively  ex- 
plored once  more.  Some  years  ago  a  flotation  plant 
was  erected  for  the  treatment  of  these  ores,  but  it  was 
not  worked  regularly,  owing  to  lack  of  labour  required 
for  the  development  of  the  deposits.  The  directors 
are   offering    the   remaining   10,000  shares  pro   rata 


the  result  of  bringing  the  total  receipts  to  a  substanti- 
ally higher  figure.  The  same  policy  was  pursued  during 
the  second  half  of  1910,  but  not  to  the  same  extent. 
The  tonnage  raised  and  milled  was  40,315,  compared 
with  44,659  during  the  second  half  of  1910,  and  47,279 
during  the  first  half  of  1910.  The  concentrate  sold  was 
852  tons,  compared  with  877  tons  and  852  tons,  and 
the  recovery  was  4738  lb.  per  ton,  compared  with 
44  lb.  and  40'4  lb.  The  average  price  realized  per  ton 
was/117.  6s.  6d.,  compared  with  /97  15s.  2d.  and 
/88.  13s.  8d.,  and  the  receipts  were  ;^100, 048,  com- 
pared with  /85,819  and  £15,62,9.  The  profit,  after 
payment  of  royalty,  was  /36,370,  compared  with 
/24,515  and  /13,018.  The  working  costs  were  not 
substantially  different.  The  shareholders  havereceived 
;^34,000  as  dividend,  being  at  the  rate  of  10%  for  the 
half-year.  The  new  battery  of  8  air-cushion  stamps  is 
at  work,  and  a  further  four  are  to  be  erected.     The 


among  shareholders  at  par,  £l  ;  they  have  already  re- 
ceived an  offer  for  the  whole  or  any  part  of  the  issue. 
At  the  shareholders  meeting  Mr.  Thomas  said  that  re- 
cent developments  at  depth  had  disclosed  important 
bodies  of  ore. 

Wheal  Vor. — This  old  tin  mine  is  situated  in  the 
Breage  district  of  Cornwall,  a  few  miles  south  of  Hayle 
It  was  reopened  in  1906  by  the  Dolcoath  group,  but 
misfortune  has  dogged  the  steps  of  the  enterprise.  The 
electric  pumps  first  supplied  were  of  faulty  construc- 
tion, and  the  engines  driving  those  substituted,  after 
having  unwatered  the  mine  to  864  ft.  below  adit,  broke 
down.  Enough  exploratory  work,  however,  was  done 
in  the  interval  to  prove  that  there  are  several  veins 
worth  following.  Owing  to  the  difficulty  of  raising 
further  funds  the  mine  has  been  idle  for  a  year.  In 
the  report  of  the  company  for  the  year  ended  April 
30,   now  issued,  the  directors  speak    more  hopefully 


238 


THE    MINING    MAGAZINE 


of  the  prospects  of  another  unvvatering  and  reopening. 
They  point  to  the  fact  that  electric  power  can  be  ob- 
tained cheaply  from  the  new  central  electric  station  at 
Hayle,  which  is  supplying  Dolcoath  and  South  Crofty, 
and  will  shortly  send  current  to  Geevor  at  Pendeen. 
By  taking  advantage  of  this  opportunity  cheap  power 
could  be  obtained  with  little  outlay  of  capital.  The 
directors  are  intending  to  call  shareholders  together 
before  long  in  order  to  discuss  the  possibility  of  raising 
the  necessary  money.  Frank  Harvey,  J.  M.  Holman, 
and  Gilbert  Pearce  have  resigned  from  the  board,  and 
James  Wickett  and  C.  V.  Thomas  have  taken  their 
place. 

Carn  Brea  &  Tincroft — The  report  for  the  half- 
year  ended  June  30  of  this  Cornish  company  shows 
that  the  yield  per  ton  has  fallen  seriously,  being  only 
22 '29  lb.   of  tin  concentrate  per  ton  of  ore  stamped. 
Since  the  present  company  was  formed  in  1900  only 
once,  namely,  during  the  second  half  of  1903,  has  the 
figure  sunk  below  23  lb.,  and  the  average  has  been 
from  26  to  30  lb.     The  ore  raised  was  38,253  tons  and 
the  produce  of  tin  concentrate  380  tons,  as  compared 
with  38,892  tons  and   472    tons   during   the   previous 
half-year.     The  best  results  were  obtained  during  the 
first  half  of  1909  when  36,825  tons  yielded  567  tons  of 
concentrate.     The  income  from  the  sale  of  tin  con- 
centrate was  ;r39,038,  figures  practically  identical  with 
those  of  the  two  other  periods  quoted  above,  the  price 
of  tin   being  the  compensating  factor.       During   the 
past  year  the  average  price  obtained  for  the  concen- 
trate   was   ;^102   as   compared  with  ;^82  during   the 
second  half  of  1910  and  /69  during  the  first  half  of 
/1909.      The  sale  of  wolfram,  copper,  and  arsenic 
ores  and  concentrates  brought  the  total  receipts  to 
£^1,057.       The    working    cost    was   ;^41,192,    figures 
slightly  higher  than  the  average  of  the  last  four  years. 
To  this  has  to  be  added  ;^1501  for  royalties,  so  that  the 
result  of  the  half-year's  work  is  a  loss  of  ;^1936.     No 
allowance  is  made  for  depreciation.     The  current  his- 
tory of  the  company  has  been  given  in  our  correspon- 
dence pages  at  intervals  during  the  present  year  and 
we  have  recorded  the  appointment  of  Edward  S.  King, 
late  of  West  Australia,  to  the  managership.     In  his 
report  he  foreshadows  new  methods  of  payment  for 
underground    contract    work,    improvements    in    the 
handling  of  ore,  and  the  overhauling  of  the  old  dress- 
ing-plant.    He  adds:   "At  present  there  are  8  haul- 
ing shafts  and  5  pump  shafts,  and  altogether  24  en- 
gines working  under  steam,  and  one  engine  on  suction 
gas,"  a  serious  item  in  the  standing  charges.     As  re- 
gards the  Humboldt  magnetic  separator  recently  pro- 
vided for  the  removal  of  wolfram,   he  reports  that  it 
is  giving  entire  satisfaction. 

Granville  United. — This  company  was  formed  un- 
der the  limited  liability  laws  in  July  1906  to  acquire 
the  Grenville  tin  mine  to  the  south  of  Camborne, 
Cornwall,  that  had  previously  been  worked  for  many 
years  on  the  cost-book  system.  The  ore  yields  a  good 
quality  concentrate,  fairly  free  from  wolfram  and  iron, 
and  bringing  a  higher  price  at  the  tin  ticketings  than 
the  produce  of  many  of  the  neighbouring  mines.  In 
writing  of  the  company  in  our  March  issue,  we  men- 
tioned that  the  new  manager,  Henry  Battens,  has  in- 
troduced the  wholesome  practice  of  buying  supplies 
in  the  open  market  instead  of  being  dependent  en  di- 
rectors or  shareholders  interested  in  the  timber,  ma- 
chinery, and  other  trades.  At  the  same  time  we  re- 
corded that  he  had  made  a  profit  of  /4308  for  the 
half-year  ended  December  31  last,  so  reducing  the 
debit  balance  from  £l0,465  to  ;^6157.  The  report 
now  issued  covers  the  first  six  months  of  1911  and 
shows  that  in  spite  of  the  continued  water  trouble  the 


debit  balance  has  been  changed  into  a  credit  balance 
of  /799.  The  amount  of  ore  raised  was  17,059  tons 
and  the  yield  of  concentrate  was  266  tons,  as  com- 
pared with  21,047  tons  and  298  tons  during  the  second 
half  of  1910.  The  extraction  was  35  lb.  per  ton  as 
compared  with  32|  lb.  The  income  from  sales  was 
;^30,293  as  compared  with  /29,485,  and  the  profit 
after  paying  royalty  was  £6956  as  compared  with 
£4308.  The  output  has  been  smaller  than  would 
have  otherwise  been  the  case,  because  for  at  least 
half  the  time  the  water  prevented  access  to  the  best 
stopes.  It  will  be  remembered  that  last  autumn  was 
unusually  wet  and  the  pumps  were  unequal  to  the 
extra  duty  imposed.  Much  time  and  money  were 
spent  in  repairing  and  strengthening  the  pumps,  and 
aftervvari},  when  the  water  was  lowered,  in  inspecting 
and  strengthening  the  various  workings.  A  profitable 
and  promising  shoot  of  ore  has  been  found  in  the  320 
fm.  level  east  of  Fortescue's  shaft  and  a  level  is  being 
driven  at  355  fra.  west  of  the  same  shaft  to  intersect 
a  shoot  that  has  yielded  much  ore  in  the  level  above. 
Mr.  Battens  writes  hopefully  of  the  future. 

St.  Ives  Consolidated. — This  company  was  formed 
by  the  Schiff-Dietzsch  group  in  June  1908  to  acquire 
from  the  parent  company,  the  National  Minerals  Cor- 
poration, a  number  of  leases  of  old  tin  and  uranium 
mines  in  the  neighbourhood  of  St.  Ives,  Cornwall. 
This  group  started  work  in  Cornwall  at  the  Hingston 
and  Glitters  mines  near  Tavistock  eleven  years  ago, 
and  have  since  then  reopened  old  mines  near  Truro, 
and  acquired  the  West  Kitty  and  other  properties  in 
the  St.  Agnes  district.     No  profits  have  as  yet  been 
earned  by  any  of  the  ventures.     The  work  in  the  St. 
Ives  district  has  been  centred  on   the  Trenwith  mine, 
which  yields  pitchblende,  and  on  the  Giew  tin  mine. 
The  report  for  the  year  1910  states  that  the  Trenwith 
has  been  unwatered  and  that  a  subsidiary  company, 
the  British  Radium  Corporation,  is  extracting  uranium 
and  radium    compounds  at    the  laboratory  at  Lime- 
house,   London,   under  the  scientific  direction  of  Sir 
William  Ramsay.      Up  to  the  end  of  1910  the  income 
from  the  sale  of  the  products  was  /1025,  and  since 
then  a  further  £9073  has  been  received,  while  orders 
valued    at   ;^4300  are  in  course  of  execution.     The 
report  does  not  say  how  much  of  the  products   are 
radium  and  uranium  compounds  respectively.     At  the 
Giew  tin  mine  unwatering  was  at  first  undertaken  with 
a  Cornish  pump,  but  subsequently  an  electrical  instal- 
lation was  provided.     The  electric  generating  station 
contains  Diesel  oil  engines.     Twenty  stamps  and    a 
concentrating  plant  have  been  erected,  and  they  started 
work  at  the  beginning  of  1911,  chiefly  on  dump  material. 
Up  to  June  19  the  amount  of  tin  concentrate  sold  to 
the  smelters  was  25  tons.     Additional  leases  have  been 
acquired,  including  the  Trink  Hill,  and  an  old  dump, 
which  latter  is  estimated   to  contain  sufficient  tin  to 
warrant  the  erection  of  another  20  stamps.     At  the 
Giew  mine  the  water  has  been  lowered  to  480  ft.  below 
adit,  or  about  half  the  depth  of  the  former  workings. 
A  vast  amount  of  work  has  been  done  in  clearing  old 
adits  and  shafts  and  putting  them  in  order,  and  the 
report  of  Ferdinand  Dietzsch,  the  engineer,  gives  de- 
tails   on   this   point.     It   is    not    possible  however  to 
obtain  from  the  report  any  idea  of  the  ore  reserves  or 
of  the  prospects  of  the  mines  as  producers  of  profitable 
ore.     The  directors  announce  that  they  are  intending 
to  start  a  radium  spa  at  St.  Ives.     The  balance-sheet 
shows  that  the  capital  of  the  company  is  ;^220,000,  of 
which  ^'80,000  is  in  cumulative  6%  preference  shares 
and  ;^140,000  is  in  ordinary  shares,  the  latter  being  the 
purchase  price  paid  to  the  National  Minerals  Corpora- 
tion for  the  leases.     The  expenditure  during  the  period 


SEPTEMBER,    1911 


239 


from  October  1,  1909,  to  December  31,  1910,  was 
;^70,850,  of  which  ;!r44,954  was  on  plant,  machinery, 
buildings,  and  surface  works,  and  ;/^13,555  on  develop- 
ment. There  is  a  liability  of  ;if23,850  for  money  ad- 
vanced by  the  National  Minerals  Corporation.  Judg- 
ing by  the  balance  sheet  it  would  appear  that  further 
working  capital  will  be  required,  as  the  balance  of 
cash  in  hand  is  small. 

Weardale  Lead. — This  company  has  been  working 
a  group  of  lead  mines  in  Durham  county  since  1883. 
The  district  in  which  they  are  situated  is  in  the  high 
country,  consisting  of  carboniferous  limestone,  at  the 
junction  of  the  counties  of  Cumberland,  Northumber- 
land and  Durham.  The  Alston  and  Nenthead  lead 
and  zinc  mines  are  not  far  away.  The  report  for  the 
twelve  months  ended  June  30  shows  that  3129  tons  of 
ore  and  concentrate  was  smelted  yielding  2664  tons 
lead.  This  compares  with  4199  tons  yielding  3402 
tons  lead  during  the  previous  year.     The  decrease  is 


the  tube-mills.  The  cyanide  plant  extracted  45,837  oz. 
from  sand  and  14,206  oz.  from  slime.  The  total  yield 
was  200,178  oz.  valued  at  ;r838,570,  an  extraction  of 
7^dwt.  or  31s.  5d.  per  ton  milled.  The  working  cost 
was  /505,229  or  18s.  lid.  per  ton,  leaving  a  profit  of 
;^334,379  or  12s.  6d.  per  ton.  The  manager,  J.  J. 
Wessels,  has  done  much  in  the  way  of  introducing 
stoping  drills  and  he  gives  interesting  information  in 
the  report  now  published.  Our  Johannesburg  corres- 
pondent quoted  his  report  in  full,  and  made  comment, 
in  our  .\ugust  issue.  As  regards  ore  reserve,  it  was 
estimated  on  March  31  that  1,140,000  milling  tons 
averaging  72  dwt  was  ready  for  stoping,  and  in  addi- 
tion 86,000  tons  averaging  6'65  dwt.  was  reckoned  as 
partly  developed  but  not  ready  for  stoping. 

Oroya  Leonesa. — This  was  one  of  the  three  com- 
panies formed  in  1910  to  acquire  the  assets  of  the 
Oroya  Brownhill  of  Kalgoorlie  when  the  latter  com- 
pany was  dissolved  on  the  exhaustion  of  the  mine.   The 


^OVA^NNESBU/?G 


PART    OF    WITWATEESIUND,    SHOWING    POSITION   OF    liOBINSON    DEEP. 


only  temporary  and  is  entirely  due  to  the  fact  that 
much  development  work  has  been  done  at  the  Bolts- 
burn  mine.  The  income  from  the  sale  of  lead  was 
;^33,421,  and  from  the  sale  of  16,464  tons  of  fluorspar 
;^7514.  Most  of  the  lead  ore  came  from  the  Bolts- 
burn  mine  and  of  the  fluorspar  from  the  Stanhopeburn 
mine.  The  profit  for  the  year  was  ;^6473  out  of  which 
;f4896  was  paid  as  dividend,  being  at  the  rate  of  5%. 
A  year  ago  the  dividend  was  10%.  We  note  that 
Errington  Thompson,  who  did  much  good  work  for 
the  company,  resigned  the  position  of  manager  at  the 
end  of  1910  and  has  been  succeeded  by  H.  S.  Willis. 

Robinson  Deep. — This  mine  is  a  second  dqep  in  the 
central  part  of  the  Rand,  being  on  the  dip  of  the 
Robinson  Central  Deep  (now  absorbed  in  the  Crown 
Mines)  and  the  Ferreira  Deep.  It  is  controlled  by 
the  Consolidated  Gold  Fields  and  is  isolated  from 
others  of  the  same  group,  being  entirely  surrounded 
by  Wernher- Beit-Eckstein  properties.  Milling  com- 
menced in  1898  with  40  stamps,  and  the  equipment 
now  consists  of  300  stamps  and  5  tube-mills.  The  re- 
port for  the  year  ended  March  31  shows  that  scarcity 
of  labour  has  greatly  interfered  with  operations  below 
and  above  ground  and  the  average  of  stamps  running 
was  only  218.  The  tonnage  of  ore  hoisted  was  629,792 
tons,  and  after  the  removal  of  15%  waste,  533,850  tons 
went  to  the  battery.  By  amalgamation  103,654  oz. 
was  extracted  below  the  stamps  and  36,481  oz.  below 


particular  asset  acquired  was  the  Leonesa  gold  mine 
which  is  situated  near  Matagalpa,  Nicaragua.  H.  C. 
Hoover  is  chairman  of  the  company,  Bewick,  Moreing 
&  Co.  are  general  managers,  James  Brothers  are  con- 
sulting engineers,  and  J.  Semmens  Allen  is  mine 
superintendent.  The  report  now  issued  covers  the 
period  from  the  formation  of  the  company  to  March 
31.  It  shows  that  operations  have  been  greatly  hin- 
dered by  the  Nicaraguan  revolution.  The  plant  con- 
sisting of  20  stamps  and  cyanide  equipment  has  been 
delivered  and  part  of  it  has  been  erected. 

Central  Chile  Copper. — This  company  was  formed 
in  1894  to  continue  the  work  of  the  Fanulcillo  Copper 
Co.  that  was  originally  started  in  1864.  The  issued 
capital  is  ^312,468,  and  small  dividends  have  been 
paid  in  1896,  1900,  1901  and  1907.  The  old  Fanul- 
cillo company  paid  dividends  during  three  short  runs 
of  years,  but  on  the  whole  was  not  a  profitable  pro- 
position. A  large  proportion  of  the  shares  of  the  pre- 
sent company  are  held  in  France.  Eugene  A.  J. 
Goldschmid  is  chairman,  B.  C.  Hinman  is  managing 
director,  and  H.  M.  McLaughlin  is  manager.  The 
business  of  the  company  has  been  hindered  during 
the  last  two  years  owing  to  the  low  price  of  copper  ; 
not  only  are  the  profits  derived  from  the  company's 
own  ores  reduced,  but  many  of  the  mines  from  which 
supplies  of  custom  ores  are  usually  obtained  have 
been  closed.      Another  adverse  circumstance  is  the 


240 


THE    MINING    MAGAZINE 


fact  that  the  ore  raised  from  the  company's  mines  is 
of  lower  grade  than  formerly  The  report  now  issued 
covers  the  year  1910.  During  that  time  28,405  metric 
tons  of  the  company's  ore  was  smelted,  together  with 
19,872  tons  of  purchased  ores  The  content  of  the 
company's  ore  was  3'22%  copper  and  of  the  purchased 
ores  7'92%  ;  these  figures  compare  with  36%  and 
7'72%  the  year  before.  The  production  was  matte 
containing  2128  tons  copper,  and  gold  and  silver  worth 
;^10,373,  as  compared  with  2144  tons  and  ;^8485.  The 
result  of  the  year's  operations  was  a  loss  of  /1263 
which  brings  the  debit  balance  to  /7953.  The  report 
states  that  the  development  work  at  various  proper- 
ties of  the  group  continues  to  disclose  ore  but  not  in 
the  quantity  or  of  the  quality  desired.  Improvements 
are  being  made  in  the  smelting  plant  with  a  view  of 
reducing  costs. 

Mount  Morgan. — The  C6th  annual  report  of  this 
gold-copper  mine  in  Queensland  for  the  year  ended 
May  31  shows  that  the  production  of  gold  was  smaller 
than  during  the  previous  twelve  months,  while  the  out- 
put of  copper  was  practically  the  same.  No  gold  is 
now  extracted  from  oxidized  ore,  and  the  year's  work 
is  credited  with  only  an  unimportant  amount  obtained 
at  the  final  clean-up  ;  the  extraction  from  the  sulphide 
by  chlorination  and  in  the  blast-furnace  has  decreased 
for  reasons  explained  later.  G.  A.  Richard,  the  mana- 
ger, in  his  report,  shows  that  during  the  year  173,209 
tons  of  Mount  Morgan  ore  was  smelted,  yielding  5222 
tons  copper  and  89,473  oz.  gold.  Mixed  with  this  was 
52,289  tons  of  Many  Peaks  ore,  now  used  as  flux,  from 
which  was  produced  1186  tons  copper  and  479  oz.  gold. 
By  chlorination  109,371  tons  of  sulphide  ore  yielded 
51,210  oz.  gold  and  565  tons  of  copper,  and  1287  oz. 
gold  was  obtained  by  the  final  clean-up  of  the 
oxidized-ore  plant.  The  total  production  was  there- 
fore 6973  tons  copper  and  142,449  oz.  gold,  com- 
pared with  7062  tons  copper  and  187,867  oz.  gold 
the  year  before.  The  decrease  in  the  output  of  gold 
is  due  to  the  considerably  smaller  amount  of  both 
classes  of  ore  treated  ;  on  the  other  hand  the  contents 
of  both  copper  and  gold  were  slightly  higher.  It  is  not 
now  possible  to  mine  so  much  chlorinating  sulphide  from 
the  open-cut,  as  the  workings  are  deep  and  the  amount 
of  overburden  to  be  removed  is  so  great  as  to  make  this 
classof  operation  unprofitable.  As  regards  the  decrease 
in  the  output  of  smelting  ore,  this  is  due  to  the  fact  that 
only  three  furnaces  have  been  running  for  most  of  the 
time  owing  to  the  non-delivery  of  labour-saving  devices. 
It  will  be  remembered  that  the  Mount  Morgan  has 
suffered  from  labour  troubles  and  the  wages  have  been 
substantially  increased  ;  consequently  it  has  been  neces- 
sary to  take  steps  by  the  provision  of  machinery  to  cut 
down  the  number  of  employees.  During  the  period 
of  transition  it  has  been  difficult  to  keep  together  an 
efficient  staff  of  workmen.  No  prospecting  or  develop- 
ment has  been  done  during  the  year  ;  instead,  much 
work  has  been  done  for  the  improvement  of  ventilation 
and  in  preparation  for  the  stope-fiUing  system  recently 
inaugurated  The  ore  reserve  is  estimated  at  1,543,000 
tons  averaging  3^%  copper  and  8  dwt.  gold  and 
2,070,500  tons  averaging  3%  copper  and  24  dwt.  gold. 
The  directors  do  not  state  how  much  of  the  copper 
produced  was  sold,  but  they  report  that  the  average 
price  received  was  ;/^5S.  4s.  7d.  or  £2  less  than  during 
the  previous  year.  Apparently  the  amount  would  be 
about  6060  tons.  The  total  revenue  was  ;^953,292  and 
the  expenditure  including  taxes  ;^759,316.  The  direc- 
tors have  written  off  /57,413  for  depreciation.  As 
/61,727  was  brought  forward  from  the  previous  vear 
it  has  been  possible  to  distribute  /200,000  as  dividend 
during  the  year. 


TRADE    NOTES 

Most  of  the  trade  publications  mentioned  in  this 
column  are  available  for  distribution  and  the 
manager  of  "The  Mining  Magazine"  will  be 
pleased  to  secure  copies  for  persons  interested. 

Holman  Bros.,  Ltd.  are  mailing  a  circular  relating 
to  compressors  which  they  have  in  stock  for  immediate 
delivery. 

Wm.  Geipel  &  Co.  send  us  a  description  of  the 
Vulcan  reducing  valve,  which  is  designed  to  eliminate 
the  weight  and  springs  on  the  one  hand,  and  india- 
rubber  diaphragms  used  in  other  valves. 

W.  &  T.  George,  Ltd.  have  issued  a  circular  describ- 
ing their  improved  theodolite  which  sells  for  ;^3.  10s., 
and  while  not  intended  for  use  on  work  requiring  great 
care  and  accuracv,  is  practical  and  sufficiently  accurate 
for  small  land-surveys.  It  should  appeal  to  students 
desiring  practice  in  surveying. 

The  Union  Iron  Works  Company  of  San  Francisco 
have  purchased  the  business  and  good-will  of  the 
Risdon  Iron  &  Locomoli\e  Works,  and  will  continue 
to  manufacture  the  mining  and  dredging  machinery 
for  which  the  Risdon  Co.  have  been  well  known  for 
many  years. 

New  York  Engineering  Co.  have  issued  a  new  36- 
page  descriptive  pamphlet  on  the  Empire  drill.  It  is 
well  illustrated  and  printed.  We  are  informed  that 
the  demand  for  this  drill  has  increased  to  such  an  ex- 
tent that  the  company  has  been  justified  in  keeping  a 
stock  on  hand  for  immediate  delivery,  not  only  at  New 
York,  but  at  all  the  principal  mining  centres.  The 
catalogue  is  also  printed  in  Russian. 

The  Oil  Well  Engineering  Co.  have  just  issued  a 
257-page  catalogue  and  price  list,  illustrating  and 
describing  Well  Drilling  machinery  and  accessories. 
The  preface  gives  a  brief  outline  of  the  progress  in  the 
design  of  this  class  of  tool  from  the  exploitation  of  the 
Pennsvh^ania  fields  in  1859.  The  catalogue  gives  all 
the  information  necessary  to  the  purchaser. 

The  Sullivan  Machinery  Co.  issue  a  quarterly  bulle- 
tin. The  August  issue  (36  pages)  has  just  come  to 
hand,  and  contains  the  following  :  A  New  Shaft  Re- 
cord ;  Mining  Coal  at  Collinsville,  Illinois  ;  Hammer 
Drilling  at  the  Ray  ;  Damming  the  Mississippi  ;  A 
Difficult  Feature  of  Diamond  Drilling  ;  Government 
Drilling  in  Nova  Scotia  ;  Quarrying  with  Hammer 
Drills  ;  Long  Column  Arms  in  Tunnels.  The  articles 
are  well  edited  and  illustrated.  The  bulletin  accom- 
plishes its  purpose  of  supplying  news  to  those  in- 
terested in  the  application  of  labour-saving  devices  in 
economically  breaking  and  handling  ore  and  stone. 

We  acknowledge  having  received  the  following  trade 

bulletins  and  catalogues  : 

Joshua  Hendy  Iron  Works  ;  Bulletin  No.  119 
Stamp  Mills,  No.  120  Stamp  Milling  Machinery  Ac- 
cessories, No.  121  Rock  and  Ore  Crushing  Machinery, 
No.  122  Hydraulic  Giants. 

Wm.  Powell  &  Co.  ;  Catalogue  No.  10.  300  pages, 
5  by  8  in.  ;  booklet  on  valves  and  other  engineering 
specialities. 

Frenier  &  Son  ;  12-page  folder,  Sjby  4  in.,  describ- 
ing the  Frenier  spiral  pump. 

Deister  Concentrator  Co.  ;  pamphlets  describing 
the  No.  2  and  No.  3  concentrators. 

Lufkin  Rule  Co.  ;  96-page  booklet,  9  by  6  in.,  fully 
describing  measuring  tapes  and  rules,  with  prices. 

Marion  Steam  Shovel  Co.  ;  9  by  6  in.  flexible 
leather-covered  book  describing  steam  shovels  ;  also 
similar  book  on  dipper  and  elevator  dredges,  and  a  lOj 
by  7 J  in.  catalogue  giving  details  of  the  Marion  eleva- 
tor dredges  for  gold  and  tin. 


The  Mining  Magazine 


Vol.  V. 


LONDON,  OCTOBER   1911 


No.  4 


Scientia   non   habet   inimicum   nisi   ignorantem. 


T.   A.    RICKARD,    Editor.  EDGAR    RICKARD.    Business  Manager. 

PUBLISHED  BY  THE  MINING  PUBLICATIONS  LTD.,  at  819  SALISBURY  HOUSE,  LONDON,  E.C 

Issued    on    the    15th    day    of   each    month. 

Telegraphic  Address  :    Oligoclase.     Codes:  MciVe///,  both  editions.     Telephone:    8938   London    Wall. 

Branch  Offices  : 
SAN  FRANCISCO:  420  MARKET  STREET.     CHICAGO:  734  MONADNOCK  BUILDING.      NEW  YORK:  29  BROADWAY 

Agents  for  the  Colonies  : 
GORDON    &    GOTCH,    LONDON,    MELBOURNE,    Etc.    (SOUTH    AFRICA:    CENTRAL    NEWS    AGENCY,    LTD.) 

Registered  with  the  G.P.O.  for  transmission  to  Canada  by  Canadian  Magazine  Post. 


SUBSCRIPTION    RATES. 

United  Kingdom  and  Canada.  12  Shillings  (Single  Copy,  Is.)    ...    Abroad,  16  Shillings  (Single  Copy,  Is.  4d.) 


CONTENTS. 


PAGE 

Review  of  Mining 242 

Statistics  of  Production 249 

Editorial 

Notes 250 

Zinc  Metallurgy 252 

Agricola  254 

Prestea 256 

East  Rand  Proprietary  257 

Grinding  Machines 259 

Deep  Mining  at  Bendigo 260 

The  Generosity  of  Science 261 

Nipissing  and  Camp  Bird 262 

Special  Correspondence 

Toronto 265 

Johannesburg 267 

Salt  Lake  City 269 

Mexico 272 

Camborne 273 

Melbourne 274 

New  York 277 

Articles 

The  Finance  of  a  Mine.    V 

M.  H.Burnham  280 

Vanadium  in  New  Mexico 

Brigham  Leatherbee  282 

Losses  in  Cyanidation  H.Forbes  Julian  284 

The  Oil  Industry  of  California  

William  Forstner  29 1 

Water-Borne  Packing  for  Stope-Fill- 

ing Edgar  Pam  295 


PAGE 

Metal  Markets 264 

Personal 279 

Discussion 

Nipissing W.  G.  Miller  301 

Speculation  in  Mining...//.  C.  Hoover  301 
Ball-Mill  Practice... Dona/J  F.  Foster  304 
Most  Productive  Gold  Mine  ...L.O.H.  304 
Slime  Settlement   Courtenay  De  Kalb   305 

Ventilation  in  Mines Frank  Reed  305 

Malaria Stephen  J.  Lett  306 

Precis  of  Technology 

Zinc-Dust  Precipitation 307 

Tunnel  Driving 307 

Eclipse  Filter  for  Slime 308 

Electrostatic  Concentration  of  Zinc  Ore  308 

Cottrell's  Fume  Settler  308 

Tin  in  Rhodesia 309 

Johnson's  Electric  Zinc  Furnace 310 

Electric  Smelting  of  Zinc- Lead  Ores..  310 

Ore-Shoots  at  Pachuca  311 

Removing  Oil  from  Return  Feed- Water  312 

Zinc  Oxide 312 

Continuous  Cyanidation 312 

Current  Literature 313 

Books  Reviewed 314 

Company  Reports 315 

Trade  Notes  320 


REVIEW    OF    MINING 


Introductory. — A  month  ago  we  looked 
forward  to  the  end  of  the  political  crisis  arising 
from  international  competition  in  Morocco, 
and  we  anticipated  a  revival  of  share  specu- 
lation on  the  signing  of  the  treaty  between 
France  and  Germany.  That  event  is  still  in 
the  near  future  but  it  seems  so  well  assured 
as  to  have  been  discounted  by  the  stock- 
exchanges.  Before  it  ceases  to  be  a  perturb- 
ing factor  another  centre  of  unrest  has  been 
created.  The  Moroccan  imbroglio  is  followed 
by  the  Tripolitan  highbindery  with  its  menace 
of  a  recrudescence  of  the  Near  East  question 
by  the  undermining  of  Turkish  power  in  the 
Balkans.  However,  the  danger  is  so  obvious 
as  to  call  for  a  speedy  effort  to  check  it,  and 
we  expect  that  the  meekness  with  which  the 
Turks  have  met  the  Italian  demands  presages 
an  early  pacification  in  the  Mediterranean, 
Then,  if  American  political  activity  does  not 
interfere  too  greatly  with  the  course  of  busi- 
ness on  the  other  side  of  the  Atlantic,  we  may 
reasonably  expect  a  period  of  renewed  op- 
timism. 

The  last  four  weeks  have  given  ample  proof 
that  the  mining  market  has  reached  a  level  at 
which  real  holders  have  ceased  to  be  sellers. 
Speculative  holdings  have  been  reduced  to  an 
abnormal  degree.  Intrinsic  values  begin  to 
compare  favourably  with  market  quotations. 
All  weak  positions  have  been  forcibly  liqui- 
dated and  the  Stock  Exchange  itself,  by  rea- 
son of  continual  political  disturbances,  and  as 
a  measure  of  precaution,  is  rather  on  the  bear 
track.  How  otherwise  could  it  be  explained 
that  the  actual  declaration  of  war  between  two 
European  powers  has  had  no  depressing  effect 
on  prices ;  on  the  contrary,  it  leaves  the  mar- 
ket looking  stronger  and  somewhat  higher  all 
round.  The  public  appears  to  have  awakened 
to  the  undeniable  fact,  as  remarked  in  our  last 


issue,  that  mining  shares  dealing  with  proper- 
ties producing  gold  and  other  precious  metals, 
and  spread  all  over  the  world,  outside  the  pos- 
sibility of  political  disturbances,  are  immune 
from  a  European  conflagration.  If  that  be  the 
case  a  new  era  may  have  started  for  this  much 
abused  department  of  the  Stock  Exchange. 
Strange  to  say  the  very  people  who  are  the 
most  ready  to  heap  abuse  on  the  mining  houses 
are  largely  responsible  for  the  losses  they 
lament.  At  a  time  like  the  present  they  will 
steadfastly  refuse  to  buy  a  single  share.  They 
want  to  be  led  like  sheep,  and  will  only  listen 
to  advice  when  the  value  of  shares  has  already 
appreciated  by  50%  to  100%.  Let  the  inves- 
tor and  speculator  study  the  reports  from  the 
mines  when  markets  are  dull  and  they  will 
have  less  cause  to  regret  their  share- dealings. 
Revenue  will  then  be  in  some  proportion  to 
the  price  paid.  During  a  period  of  prolonged 
depression,  such  as  the  present,  the  big  houses 
cannot  help  making  money.  They  buy  in 
times  of  political  disturbance,  as  now,  when 
they  would  much  sooner  keep  their  cash  than 
accumulate  scrip,  and  they  sell  when  every- 
body is  clamouring  for  shares  at  inflated  prices. 
We  believe  therefore  that  a  careful  selection 
of  good  dividend-payers,  and  of  such  stock  as 
by  the  nature  of  developments  allows  a  favour- 
able forecast  for  the  future,  is  going  to  benefit 
those  who  buy  now. 

Turning  to  the  different  departments  of  the 
mining  market,  we  find  that  there  is  a  con- 
stant stream  of  buying  orders  from  the  Cape. 
Speculators  in  Europe  are  scared  and  those 
on  the  spot  appreciate  the  fact.  The  industry 
itself  is  sound  and  the  resident  population  is 
investing  in  enterprises  with  the  development 
of  which  they  are  familiar.  The  East  Rand 
trouble  is  largely  discounted  in  the  present 
price,    although    it    is    gradually     becoming 


242 


OCTOBER,    1911 


243 


apparent  that  the  root  of  the  trouble  is  the 
fact  that  the  Company  has  been  crushing  ore 
above  its  average  grade.  The  commission, 
which  has  been  appointed  by  the  Company  in 
accordance  with  the  new  mining  law,  may  be 
able  to  throw  light  on  the  affair,  but  its 
findings  are  likely  to  prove  belated.  It  would, 
however,  be  fallacious  to  draw  the  conclusion 
that  the  whole  industry  is  being  conducted  in 
an  unbusinesslike  fashion.  On  the  contrary, 
we  are  inclined  to  believe  that  this  disclosure 
will  put  the  fear  of  the  Lord  into  the  heart  of 
those  controlling  mining  operations. 

The  Rhodesian  market,  which  recently  ex- 
hibited a  strong  undercurrent,  has  also  suf- 
fered ;  but  a  return  of  public  confidence  will 
not  be  hastened  by  the  obvious  efforts  to  create 
a  boom.  Chartered  were  a  strong  spot.  Apart 
from  its  mineral  resources  the  country  offers 
big  possibilities  in  agriculture,  as  explained 
by  Mr.  Percy  J.  Inskipp,  the  head  of  this  de- 
partment of  the  Chartered  Company,  who  has 
just  returned  from  a  long  sojourn  in  Rhodesia. 
Other  shares  prominent  in  the  public  eye  were 
Cam  &  Motor  and  Shamva.  The  West  Afri- 
can market  had  a  good  appearance  until  the 
Tripolitan  trouble  turned  the  scale,  but  shares 
like  Prestea,  Taquah,  Abosso,  and  a  few  smal- 
ler concerns,  have  attracted  attention.  We 
refer  to  the  Prestea  again  on  another  page- 
Among  Australians,  Great  Fingall  was  in  quiet 
demand.  The  developments  on  the  17th  and 
18th  levels  so  far  bear  out  the  favourable 
geological  opinion  on  which  the  scheme  of 
exploratory  work  is  based.  A  sharp  upward 
movement  has  affected  Waihi  Grand  Junction, 
where  excellent  developments  in  depth  are  re- 
ported. Copper  shares  are  entirely  under  the 
influence  of  New  York  fluctuations,  but  at  the 
time  of  writing  they  have  a  firm  appearance, 
as  the  copper  statistics  continue  favourable. 
Russian  securities  were  subjected  to  heavy 
liquidation  from  Paris  and  it  looks  as  if  they 
were  for  the  present  under  a  cloud.  Oil  shares 
continue  dull. 


Transvaal.  —  The  statistics  for  August 
showed  a  further  increase  in  gold  produc- 
tion, a  new  record  of  713,407  ounces,  worth 
;£'3,030,360,  being  made  for  the  month.  For 
eight  months  the  total  yield  is  ;6'22,932,713, 
as  agamst  ;^3 1,995,266  for  the  12  months  of 
last  year.  Owing  to  the  East  Rand  Proprie- 
tary's trouble,  the  averages  for  August  were 
spoiled,  the  yield  being  26s.  8d.  per  ton,  on. 
the  2,107,809  tons  treated,  as  against  27s.  2d. 
in  July.  The  cost  was  one  penny  less  at 
17s.  9d. ;  hence  the  resulting  profit  was  5  pence 
less,  at  8s.  lid,  per  ton.  The  total  profit  was 
^967,457  as  against  ;^969,687  in  July.  In 
August  1910  the  yield  was  28s.  3d.,  the  cost 
17s.  8d.,  and  the  profit  10s.  6d.  per  ton.  As 
regards  labour  the  official  returns  show  a  de- 
crease of  1772  natives  on  the  gold  mines,, 
bringing  the  total  to  179,810^  as  compared  with 
180,831  at  the  same  date  a  year  ago.  The  de- 
crease has  been  continuous  since  April.  In  a. 
recent  speech  before  the  Chamber  of  Mines  at 
Johannesburg,  the  chairman,  Mr.  H.  O'K. 
Webber,  said  that  the  gold  mines  had  67*4%- 
of  their  complement  of  labour  as  against  76'3% 
at  the  same  date  last  year.  He  predicted  an 
early  increase,  the  seasonal  migration  being 
nearly  at  an  end.  Owing  to  competitive  re- 
cruiting among  the  groups  and  excessive  fees 
paid  to  the  recruiting  agents  by  two  of  the 
groups,  it  is  likely  that  drastic  action  may  be 
taken  by  the  others.  It  is  reported  that  the 
Government  has  been  asked  to  undertake  the 
recruiting,  as  being  a  partner  with  the  mining 
companies  and  a  beneficiary  from  their  suc- 
cessful operations ;  but  it  is  unlikely  that  the 
Government  will  saddle  itself  with  the  dis- 
agreeable task. 

A  later  telegram  from  Johannesburg  states- 
that  the  supply  of  native  labour  decreased 
during  September  by  145,  as  compared  with 
an  increase  of  1369  in  the  correspondmg 
month  last  year.  This  is  a  distinct  disap- 
pointment, as  a  turn  in  the  tide  of  Kaffir  mi- 
gration is  expected  at  this  season.     An  influx 


244 


THE    MINING    MAGAZINE 


of  20,000  '  boys  '  is  said  to  be  due  from  the 
northern  districts  during  the  next  three  months. 
The  directors  of  the  Transvaal  Gold  Mining 
Estates  are  to  be  complimented  on  the  frank 
statement  issued  by  them  on  September  30. 
It  appears  that  the  concession  under  which 
they  hold  one  of  their  claims  at  Pilgrim's 
Rest  expires  on  May  5,  1913.  Hence  it  is 
necessary  to  extract  more  ore  from  the  mine 
on  this  claim  than  from  their  other  workings, 
and  as  this  ore  is  lower  in  grade  than  the  aver- 
age of  the  group,  the  yield  in  the  mill  will 
suffer  until  the  tonnage  can  be  increased  pro- 
portionately. 

On  October  2  the  Modderfontein  B  mill 
started  crushing  and  a  declaration  of  output 
may  be  expected  next  month.  At  the  New 
Modderfontein  the  Merrill  precipitation-press 
is  being  used,  as  at  the  Brakpan.  At  the 
Village  Deep  a  trial  is  being  made  with  the 
Hardinge  tube-mill.  At  the  City  Deep  the 
Nissen  stamp  is  to  be  installed. 

Rhodesia. — A  new  record  was  made  in 
August,  the  output  of  gold  being  57,890 
■ounces,  worth  ^243,712,  which  compares  with 
;^237,517  in  July  and  ;^191,423  in  the  corres- 
ponding month  of  last  year.  The  production 
for  the  eight  months  of  the  current  year  is 
^57,943  more  than  it  was  during  the  corres- 
ponding portion  of  1910.  The  Globe&  Phoenix 
yielded  ^44,974  from  16,886  tons  ;  this  is  less 
than  in  July  and  about  the  same  as  in  June. 
The  most  notable  increase  is  at  the  Lonely 
Reef,  where  the  yield  is  ^13,906  from  3480 
tons,  as  against  ;/ril,673  from  2940  tons  in 
July.  The  only  other  gain  of  any  consequence 
is  made  by  the  Thistle- Etna,  the  output  being 
/4726  from  3100  tons,  as  against  4195  from 
2600  tons  in  July. 

A  cablegram  announcing  a  slackening  of 
production,  owing  to  insufficiency  of  labour, 
■depressed  shareholders  in  Globe  &  Phoenix. 
The  half-yearly  report  issued  recently  is  fairly 
satisfactory.  Details  concerning  the  workings 
indicate  the  irregular  distribution  of  the  rich 


ore.  Metallurgical  progress  is  noteworthy, 
the  treatment  of  the  antimonial  gold  ere  having 
been  solved  by  Mr.  H.  T.  Brett,  as  described 
by  him  in  our  July  issue.  Additional  roasting 
plant  is  to  be  provided,  enabling  further  ex- 
traction of  gold  from  the  slime. 

Copper  mining  in  Central  Africa  is  nearly 
synonymous  with  the  Tanganyika  Concessions, 
but  we  note  that  the  Kafue  Copper  Develop- 
ment Co.  is  doing  good  work.  The  properties 
were  described  by  Mr.  Owen  Letcher,  in  our 
last  issue,  as  being  situated  in  the  hook  of 
the  Kafue  river  "  in  Northwest  Rhodesia.  A 
report  recently  issued  states  that  the  ore  broken 
in  the  Silver  King  mine  is  being  carried  to  the 
Sable  Antelope  mine,  where  a  smelter  is  in 
operation.  So  far  4000  tons  of  40%  copper  ore 
has  been  mined.  Smelting  has  been  started 
and  the  first  10  days  operation  yielded  187  tons 
of  matte  assaying  75%  copper.  It  is  expected 
that  the  monthly  output  will  be  300  tons  of 
matte  worth  ;^40  per  ton.  This  will  be  stored 
until  April  owing  to  lack  of  transport. 

The  Native  Labour  Association  has  issued 
figures  that  indicate  the  unsatisfactory  efforts 
to  recruit  workers  for  the  mines  of  Rhodesia. 
A  decrease  of  8102  is  shown  in  the  number  of 
natives  recruited  during  the  first  seven  months 
of  the  current  year  as  compared  with  the  cor- 
responding period  of  last  year.  Inability  to 
increase  the  supply  is  due  mainly  to  the  labour 
necessities  of  adjoining  territories,  especially 
Nyasaland  and  Northwest  Rhodesia,  where 
emigration  has  been  prevented.  The  position 
therefore  is  serious,  and  attention  has  been 
drawn  to  it  by  the  confession  of  the  Globe  & 
Phoenix  management  that  it  is  unable  to  keep 
its  mill  going  owing  to  scarcity  of  labour. 
Other  mines,  such  as  the  Eldorado,  Selukwe 
Columbia,  Lonely  Reef,  and  Thistle- Etna, 
are  believed  to  be  hampered  by  the  same 
cause.  The  farms  are  competing  and  the 
Rand  is  attracting  natives  by  higher  wages. 
It  would  appear  therefore  that  a  continued 
scarcity  of  labour  in  Rhodesia  is  likely. 


OCTOBER,    1911 


245 


Canada. — At  Porcupine  new  discoveries 
have  been  made  in  the  Mclntyre  and  North 
Dome  mines,  and  on  the  Dome  itself,  but 
prospecting  in  the  northern  portion  of  Tisdale 
has  proved  disappointing.  At  Swastika  several 


W.  J.  Lorhig,  C.  B.  Flynn,  Gerard  Lovell,  Er7iest  WiUiams, 
J.  Malcolm  Maclaren,  and  a  Photographer,  at  Porcupine. 


claims,  belonging  to  the  Timmins  brothers 
(such  as  the  Dixon  and  Miller  -  Middleton 
groups),  are  to  be  joined  to  the  Hollinger,  the 
capital  for  which  will  then  be  increased.  A 
spectacular  showing  of  ore  is  to  be  seen  on 
the  Dome  property.  After  the  fire  some  strip- 
ping of  low-lying  ground  exposed  a  quartz  vein 
several  feet  wide  ;  in  it  appears  a  streak  two 
inches  thick  (and  18  inches  long)  of  practically 
solid  gold.  Other  smaller  streaks  of  the  same 
kind  appear  over  an  area  of  60  by  5  feet.  If 
the  Dome  had  been  a  virgin  claim  this  dis- 
covery would  have  caused  a  stampede. 

West  Africa. — For  the  second  time  a 
month's  output  of  gold  exceeds  ;^100,000.  In 
August  it  amounted  to  25,385  ounces,  valued 
at  ;^103,753.  This  compares  with  ;^91,955 
in  July  1911,  ^57,713  in  August  1910,  and 
;^100,056  in  May  1909,  the  previous  high  re- 
cord. For  the  eight  months  the  output  is  now 
;^652,032,  as  against  ;^533,798  during  the 
corresponding  period  a  year  ago,  but  it  was 


THE    RICH    STREAK    ON    THE    DOME    CLAIM    AT    PORCUPINE. 

new  finds  are  announced.     The  manager  of  £67l,7Q?>  in  the  first  eight  months  of  1909. 

the  Hollinger  is  completing  his  sampling,  with  The  chief  feature  of  August  was  the  resump- 

aSview  to  an  estimate,  which  however  is  not  tion  of  milling  at  the  Taquah,   which  gave 

likely  to  be  made  known  to  the  public.    This  1771  oz.  from   1443  tons.     The  Abosso  and 

may  be  due  to   the   fact   that  the  adjoining  both  of  the  dredging  companies  show  gains 


246 


THE    MINING    MAGAZINE 


while  the  two  biggest  mines,  the  Ashanti  Gold- 
fields  and  the  Prestea,  maintain  their  normal 
monthly  output  of  ;^41,000  and  ;^21,000  re- 
spectively.    Some  encouraging  news  is  pub- 
lished by  the  Wallis  Syndicate,  whose  pros- 
pecting operations  have  led  to  the  uncovering 
of  large  widths  of  low-grade  banket.     The 
rainy  season  has  hindered  progress,  but  a  re- 
newal of  useful  activity  may  be  expected  on 
the  arrival  of  Mr.  George  Macfarlane,  the  new 
manager,  who  left  London  on  September  27. 
Australasia. — In  Western  Australia  the 
reports  being  issued  by  the  Geological  Survey 
are  appreciated.     C.  O.  Larcombe's  work  at 
Oro  Banda  appears  to  indicate  a  geological 
connection  between  that  district  and  Kalgoor- 
lie.  Reports  on  Kalgoorlie  and  Southern  Cross 
are  shortly  to  appear.    Promptitude  in  publi- 
cation is  recognized  as  essential  to  the  utility 
of  such  investigations  by  the  officers  of  the 
Survey.   At  Bullfinch  everything  is  quiet.   The 
railway  so  hastily  constructed  is  working  at  a 
heavy  loss.     The  remodelled  mill  of  the  Lake 
View  is  finished  and  a  capacity  of  18,000  tons 
monthly  is  expected.     The  treatment  includes 
stage-crushing,  stamps.  Freeman  pans,  tube- 
mills,   primary   and    secondary  Wilfleys,  fol- 
lowed by  bromo-cyanide  treatment  and  filter- 
pressing.     The  Star  leases  continue  to  be  a 
valuable  asset.     Several  breakages  and  acci- 
dents have  hindered  work  at  the  Horse-Shoe. 
Experiments   are   being  made    with    twenty 
1250  lb.  stamps  crushing  through  a  4  by  4 
screen  direct  to  a  tube-mill,  followed  by  tables, 
re-grinding    in    pans,   leaching    of    sand    and 
pressing  of  slime.     General  conditions  at  Kal- 
goorlie are  depressing.      House    property    is 
falling  in  value  and  the  future  of  the  district 
generally  looks  gloomy. 

Shareholders  in  the  Golden  Horse-Shoe 
have  received  a  circular  containing  a  lengthy 
and  rambling  cablegram  from  the  secretary 
of  the  company.  Scarcity  of  labour  and 
superabundance  of  slides  in  the  mine  have 
interfered   with    production,  so    that   Mr.   E. 


Protheroe  Jones  thinks  that  the  returns  for 
this  year  will  not  reach  ^40,000  per  month. 
Why  the  manager  cannot  be  trusted  to  give 
such  information  we  fail  to  understand.  At 
the  Ida  H.  the  mill  resumed  regular  work  on 
September  1,  and  during  the  ensuing  month 
the  profit  was  increased  nearly  a  thousand 
pounds  as  compared  with  the  previous  re- 
turns. The  stoping-width  has  been  reduced 
from  over  6  feet  to  5  feet,  with  proportionate 
economy,  for  the  vein  itself  will  average  only 
20  inches. 

Conditions  at  the  Great  Cobar  are  im- 
proving. The  weak  point  was  underground, 
the  workings  not  having  been  opened  up  so 
as  to  yield  the  proper  mixture  of  ore  required 
for  economic  smelting.  This  weakness  was 
accentuated  by  the  purchase  of  the  Cobar 
gold  mine,  which  gives  a  highly  silicious  out- 
put. The  Chesney  mine,  which  also  belongs 
to  the  Great  Cobar  company,  is  developing 
satisfactorily,  and  the  old  concentration  plant 
is  being  re-arranged  with  a  view  to  eliminat- 
ing the  excess  of  silicious  material  in  the  form 
of  slate.  Mr.  Nicholas  Treloar,  formerly  at 
Butte,  is  now  mine  superintendent  and 
worthily  supplements  the  skilful  metallur- 
gical work  of  Mr.  H.  C.  Bellinger.  Rumours 
of  the  latter's  resignation  have  now  ceased. 

A  strike  of  miners  at  Mount  Lyell  on  Sep- 
tember 24  has  compelled  a  complete  cessation 
of  operations  at  the  mines  and  smelters  in  that 
important  copper  district  of  Tasmania.  On 
October  2  it  was  announced  that  a  further 
strike  had  ensued  among  engine-drivers,  de- 
manding a  rate  of  wages  recently  advocated  by 
the  award  of  the  Arbitration  Court.  The  com- 
pany's chemical  works  continue  in  operation. 

The  agitation  in  favour  of  an  export  tax  on 
base-metal  ores  is  not  instigated  by  mine  op- 
erators, but,  by  labour  agitators,  under  the 
lead  of  the  Newcastle  Trades  Hall,  with  a 
view  to  political  support.  Such  an  impost 
would  eventually  be  borne  by  the  miner  and 
not  by  the  foreign  contractor.     The  cry  for 


OCTOBER,    1911 


247 


Australian  smeltingof  Australian  oresis cheap; 
it  does  not  reflect  an  economic  necessity.  Our 
correspondent  sends  the  latest  news  from 
Broken  Hill. 

India. — The  North  Anantapur  company  is 
raising  further  capital  for  the  purpose  of  pro- 
secuting developments,  by  the  issue  of  25,000 
new  shares  entitled  to  a  non-cumulative  divi- 
dend of  20?'o.  Since  the  formation  of  this  com- 
pany in  1908  much  development  has  been 
done,  but  no  large  amount  of  profitable  ore 
has  been  found.  The  lodes  are  so  persistent 
and  the  shoots  of  ore  so  promising  that  the 
directors  and  shareholders  are  unanimous  in 
proceeding  further.  The  company  has  a  suffi- 
ciently good  mechanical  equipment,  of  20 
stamps,  air-compressors,  etc.,  and  no  further 
expenditure  will  be  required  in  this  direction. 
The  present  monthly  output  is  about  1400 
tons,  with  an  average  content  of  from  6  to  8 
dwt.,  but  recent  developments  have  disclosed 
ore  of  higher  grade  than  this. 

Mexico. — The  most  important  news  is  the 
peaceable  choice  of  a  new  President  in  the 
person  of  the  revolutionary  leader.  Foreigners 
in  Mexico,  however,  are  still  anxious  concern- 
ing the  future,  for  it  remains  to  be  seen  what 
support  Madero  can  retain  after  he  has  tried 
vainly  to  please  all  his  followers.  At  El  Oro 
the  new  San  Carlos  vein  in  the  Esperanza 
is  opening  up  well ;  the  sulphide  vein  of  the 
Mexico  is  passing  into  the  Nolan  claim ;  the 
Exploration  Company  has  relinquished  its 
option  on  the  Cometa,  a  claim  just  north  of 
the  Mexico  ;  and  the  El  Oro  itself  is  main- 
taining its  record  for  economic  work  and  effi- 
cient administration. 

United  States.  —  The  wrecking  of  an- 
other steamer  carrying  mail  is  announced  by 
the  Alaska  Mexican  companj',  to  explain  a 
delay  in  the  publication  of  its  monthly  output. 
This  serves  again  to  draw  attention  to  the  poor 
service  given  by  the  steamship  companies  on 
the  Pacific  coast  of  North  America.  It  is 
so  bad  as  to  constitute  a  menace  to  travel  in  a 

4—2 


region  that  is  not  only  picturesque  and  inter- 
esting, but  of  growing  industrial  importance. 

It  is  announced  that  the  proposed  merger 
of  the  Calumet  &  Hecla  with  nine  other  com- 
panies, in  which  it  holds  a  controlling  interest, 
has  been  abandoned  owing  to  the  prospect  of 
endless  litigation.  The  talk  of  a  big  merger 
which  has  been  a  cloud  on  the  American 
copper  industry  for  so  long  has  now  finally 
vanished  in  the  hot  air  of  the  trust-buster. 
The  New  York  copper  market  is  dull  and 
will  continue  to  be  so  until  the  prevailing  de- 
pression in  American  industry  is  lifted  by 
decisive  legislative  action  one  way  or  the 
other. 

Siberia.— The  report  of  Mr.  C.  M.  Rolker 
covering  nine  months'  operations  by  the  Lena 
Goldfields  does  not  include  details  concerning 
the  three  summer  months  during  which  the 
major  part  of  the  production  is  won.  There- 
fore the  report  possesses  scant  interest. 
Moreover,  it  may  be  pointed  out  that  the 
revenue  credited  for  the  year  ending  June  30, 
1911,  did  not  include  the  gold  won  from 
200,000  cubic  yards  remaining  on  the  dump 
unwashed  (as  shown  by  the  difference  be- 
tween the  quantity  hoisted  and  the  quantity 
washed),  but  the  debit  did  include  the  cost  of 
mining  and  hoisting  this  amount  of  gravel. 
Thus  his  figures  are  apt  to  prove  confusing. 
The  Orsk  Goldfields  reports  continued  suc- 
cessful work  by  the  stacker-scow,  a  little 
machine  that  has  proved  highly  successful, 
pending  the  completion  of  the  dredger  itself, 
the  ■  construction  of  which  has  progressed 
sufficiently  to  permit  of  a  trial  before  the 
winter  stops  operations.  The  stacker  was  de- 
scribed by  Mr.  J.  P.  Hutchins  in  our  issue  of 
November,  1910  ;  but  it  is  well  to  add  that  to 
Mr.  C.  W.  Purington  the  company  owes  the 
adoption  of  the  machine,  which  now  includes 
a  gold-saving  appliance  on  a  scow  and  a  log- 
washer  for  disintegrating  clay. 

The  Central  Mining  group  has  been  in- 
vestigating an  important  concession  covering 


248 


THE    MINING    MAGAZINE 


also  some  gold  and  platinum  mines,  in  the  Ural 
region.  Johnson,  Matthey  &  Co.  have  a  half 
interest.  The  examination  was  made  by  Mr. 
W.  M.  Chandler.  The  incident  is  interesting 
as  exemplifying  the  wide  scouting  for  new 
business  on  the  part  of  a  firm  formerly  identi- 
fied with  South  African  industry. 

Various.— Gold  mining  in  Egypt  is  not 
quite  dead  yet,  as  is  shown  by  the  operations 
at  the  Barramia  mine.  A  return  of  ;^18,889 
from  1861  tons,  including  a  yield  of  i^lOOO 
worth  of  gold  from  1121b.  of  ore,  at  130  feet, 
indicates  a  patchy  gold  distribution,  but  it  is 
promising.  Prospects  at  250  feet  are  said  to 
be  encouraging. 

In  Chile,  a  discovery  of  gold,  followed  by 
local  excitement,  is  announced  as  having  been 
made  in  the  department  of  Curepto,  in  the 
province  of  Putu.  A  later  telegram  from  San- 
tiago gives  Constitucion  as  the  locality  and 
explains  that  a  stone  in  the  foundation  of  a 
house  was  found  richly  impregnated  with  gold, 
leading  to  a  search  for  its  place  of  origin  on  a 
neighbouring  hill.  In  an  outcrop  of  soft  quartz 
a  patch  of  rich  stuff,  yielding  ^15,000  worth 
of  gold,  was  subsequently  found,  and  a  local 
company  has  been  formed  to  start  operations. 

According  to  telegraphic  despatches,  a  party 
of  prospectors  has  found  rich  gold  deposits  in 
Baffin  Land,  a  large  island  off  the  Labrador 
coast,  on  Davis  Strait  and  opposite  Greenland. 
It  is  said  at  St.  John's,  Newfoundland,  that  5 
tons  of  quartz  yielded  1  oz.  of  gold  per  ton. 

Tin. — The  boom  in  Tronoh  shares  and  the 
weakness  in  quotations,  which  has  bothered 
the  sort  of  perplexed  shareholder  who  writes 
a  protesting  letter  to  the  financial  Press,  may 
be  explained  first  by  the  coming  of  the  mon- 
soon, with  rain  that  floods  the  open  workings, 
and  secondly  by  the  fact  that  during  the  ab- 
sence of  the  manager  in  England  the  sub- 
manager  extracted  a  rich  patch  kept  in  reserve 
for  such  a  rainy  day  as  is  literally  afforded  by 
the  monsoon.  On  October  3  a  cablegram  was 
received  stating  that  heavy  rains  and  a  dam- 


aged dam  had  been  followed  by  flooding  of  the 
mine  workings.  The  output  for  September 
was  360  tons  of  tin-stone  valued  at  ^35,000  as 
against  446  tons,  worth  ;^50,750,in  August,  the 
profit  in  September  being  ^17,200  as  against 
^^53,500  in  June.  On  October  4  Mr.  Harry 
D,  Griffiths,  the  manager,  who  had  just  arrived 
at  the  mine,  cabled  that  the  workings  were 
submerged  but  that  they  could  be  unwatered 
in  8  days.  The  loss  of  output  is  150  tons,  but 
any  forecast  of  the  future  is  difficult  at  present. 

On  the  north-east  coast  of  Tasmania,  an 
important  find  has  been  made  at  the  Banca 
tin  mine.  Drill-holes  indicate  the  existence 
of  several  layers  of  rich  material.  By  the 
completion  of  a  trail  21  miles  long  between 
Zeehan  and  Queenstown  a  valuable  aid  has 
been  given  to  prospecting  in  localities  hitherto 
almost  inaccessible. 

Oil. — We  publish  a  useful  article  on  the 
oil  industry  of  California.  It  is  noteworthy 
that  the  fight  started  a  year  ago  by  the  can- 
cellation of  agreements  between  the  Standard 
Oil  and  Asiatic  Petroleum  companies  is  ru- 
moured to  be  on  the  eve  of  settlement.  At 
that  time  the  Standard  Oil  in  a  circular  claimed 
that  the  70  new  companies  promoted  in  Europe 
had  accentuated  the  over-production  of  oil, 
and  that  to  balance  this  the  Standard  would 
reduce  prices  with  a  view  to  stimulating  con- 
sumption. It  appears  now  that  American  ex- 
ports of  mineral  oils  have  increased  during  the 
year  from  39,000,000  to  1,500,000,000  gallons. 

At  Maikop,  an  arrangement  has  been  made 
whereby  the  various  companies  consolidate 
their  boring  operations,  which  will  now  be 
conducted  by  an  association  to  which  all  will 
jointly  contribute,  under  the  direction  of  a 
representative  committee.  The  shallow  pe- 
troliferous sand  formation  has  proved  highly 
productive,  but  the  deep  drill-holes  have 
failed  to  strike  oil.  In  Australia,  the  British 
Australian  Oil  Co.  announces  the  completion 
of  its  aerial  haulage  system  and  the  com- 
mencement of  production. 


OCTOBER,   1911 


249 


STATISTICS 

Stocks  of  Copper  in  England  and  the  Continent. 
Reported  by  Henry  R.  Merton  &  Co. 


July  31 
Tons 

Aug.  31. 
Tons 

Sept.  30 
Tons 

53,807 
5,893 
2,075 
6,250 

52,661 

5,728 
1,975 
6,550 

52,111 

5,654 

2,375 

Afloatfrom  Australia 

7,200 

Total                     

68,025 

7,550 

10.400 

66,914 

7,650 

10,800 

67,340 

7,250 

In  Hamburg  (estimated)... 

11,100 

American  Copper  Producers'  Association. 
In  Tons  of  2,240  lb. 


January  1911. 
February    ••■• 

March 

April 

May 

June 

July  

August 

September.... 


Produc- 
tion. 


51,650 
49.030 
58,273 
52,716 
56,679 
55,605 
50,075 
56,024 
51,602 


Deliveries 


Domes- 
tic 


Foreign 


18,785 
22,553 
29,500 
23,396 
28,814 
27,525 
25,438 
26,757 
25,587 


23,753 
20,139 
26,375 
27,736 
27,669 
31,902 
33.429 
31,185 
22,689 


Total 


42,538 
42.692 
55,875 
51,132 
56,483 
59,427 
58,867 
57,942 
48,276 


Stocks  at 
end  of 
month 


63,591 
69,929 
72,325 
73,909 
74,105 
70,283 
61,491 
59.573 
62,899 


Production  of  Gold  in  Rhodesia. 


Production  of  Gold  in  the  Transvaal. 


Totals,  1910... 

January  1911 

February  

March 

April  

May    

June   

July 

August  

September  


Rand 


Else- 
where 


Oz. 

7,228,588 

625,862 
585,683 
649,247 
638,421 
658,196 
657,023 
679,881 
682,405 
669,773 


Oz. 

305,532 

25,201 
24,965 
26,818 
29,293 
27,755 
27,544 
29,377 
31,002 
30,852 


Total 


Oz. 

7,534,120 

651,027 
610,828 
676,065 
667,714 
685.951 
684,567 
709,258 
713,407 
700,625 


Value 


£ 

32,002,912 

2,765,386 
2,594,634 
2,871,740 
2.836,267 
2,913,734 
2,913,734 
3,012,738 
3,030,360 
2,976,065 


Cost  and  Profit  on  the  Rand. 


Month. 

Tons 

Yield 
per  ton 

Costs 
per  ton 

Profit        Total 
per  ton       profit 

January  1911... 

February 

1.865,232 
1,712,198 
1,960,678 
1,926,583 
2,002,926 
1,986,559 
2,095,220 
2,107,809 

s.    d. 

26  6 
28    0 
28     6 

27  7 
27    7 
27    6 
27    2 
26     8 

s.    d. 

17  11 

18  3 
17  11 
17    6 
17  10 
17  11 
17  10 
17    9 

s.   d.         £ 

10     1        930,059 
10     3       R74  M?. 

March  

9    9 

10    1 

9    7 

949,415 

April 

971  858 

May 

QSfi  s?^ 

June 

9     8       960  381 

July   

9    4       969,687 
8  11        967,457 

August 

Totalsand  aver- 
ages for  1909.. 
Ditto  1910 

20.543.759 
21,432.541 

28  11 
28    6 

17    1 
17    7 

11     6      11,794,376 
10    6      11,216,105 

Natives  Employed  in  the  Transvaal  Mines. 


January  31 

February  28... 

March  31  

April  30 

May  31  

June  30 

July  31 

August  31 

September  30 


Gold 
mines 


183,268 
189,434 
193,457 
194,328 
190,392 
186,940 
181,582 
179,810 
179,619 


Coal 
mines 


,357 
i,513 
,493 
,511 
:,379 
;,212 
1,122 
;,182 
:,045 


Diamond 
mines 


9,991 
9,814 
10,061 
10,272 
10,425 
10,597 
11,054 
11,292 
11.475 


Total 


201,616 
207,761 
212,011 
213,111 
209,196 
205,749 
200,758 
199,284 
199,139 


Gold  Output  of  India. 


Year  1909 


£2,083,901 


Year  1910 
£2,104,858 


Sept.   1911 


£181,913 


1911  to  date 


£1,413,  793 


Month. 

1908 

1909 

1910 

1911 

£ 

199  388 

£ 

■?ru  fififi 

£ 

227,511 
203,888 
228,385 
228,213 
224,888 
214,709 
195,233 
191,423 
178,950 
234,928 
240,573 
199.500 

£ 

207  903 

February  

191,635            192,497 
200,615     1       202,157 
212  935     '       "'  '"fi 

203.055 
231  947 

921  296 

223,867 
224,920 
228,151 
230,792 
204,262 
205,466 
196,668 
217,316 

225,032 
217,600 
225,234 
228,296 
213,249 
222,653 
236,307 
233,397 

211  413 

June  

215  347 

July 

August  

237,517 
243  712 

September  ... 

October 

November 

December.. 

Totals  

2,526,007 

2,623,788 

2,568,201 

— 

Production  of  Gold  in  West  Africa. 


Month. 


1909 


Oz.       Value 


January  .■ 
February 

March 

April    

May 

June 

July  

August 

September 
October  ... 
November 
December 


22,817 
21,403 
23,186 
21,491 
25,104 
17,340 
17.331 
17,766 
18.125 
15,957 
17,882 
17,570 


£ 
91,112 
86,210 
93.556 
88,071 
100,056 
70,561 
70,523 
71,614 
72,963 
65,813 
73,824 
71,332 


1910 


Oz. 


17,357 
16,976 
17,627 
16,363 
16,590 
17.194 
15,564 
13,921 
11,497 
13,341 
14,021 
15,042 


235,972  955,635  185,493  755,985    — 


Value 


£ 

70,699 
68,469 
71,954 
67,069 
68.355 
70,988 
58,551 
57,713 
47,746 
55,046 
57,658 
61,737 


1911 


Oz. 


15,903 
15,179 
16.387 
17,237 
24,427 
22,555 
22,510 
25,385 


Value 


£ 

66.107 
63,081 

67,673 
70,880 
96,409 
92,174 
91,955 
103,753 


Production  of  Gold  in  Western  Australia. 


Month. 

Export 
oz. 

Mint 
oz. 

Total 
oz. 

Total 
value 

Total,  1910 

363,496 

1,209,856 

1,573,352 

£ 

6,682,042 

January  1911  

17,463 
22,047 
12,296 
20,455 
22,076 
10,523 
15,334 
11,521 
5,011 

102,035 
84,991 
93,267 
91,791 
88,952 

106,464 
97,387 

102,477 

114,615 

119,498 
107,038 
105,563 
112,246 
111,028 
116,987 
112,721 
113,993 
119,626 

507,592 

454,666 

March         „     

448,426 
476,787 

471,615 

497,188 

lulv                     

478,805 

484,168 

508,135 

Other  Australasian  Gold  Production. 


Queensland 

New  South  Wales 

New  Zealand 

Victoria 


1909 


£ 

1,916,468 

869,546 

2,006,910 

2,897,340 


1910 


£ 

1,840,337 

803,727 

1,896,322 

2,422,700 


September 
1911 


£ 

146.975 
70,320* 
164,492 
185,164 


1911 
to  date 


£ 

1,208,160 
503.111* 
1,382,651 
1,590,122 


*  August  figures  only. 


Sale  of  Tin  Concentrate  at  Redruth  Ticketings. 


Tons 

Value 

Average 

Tulv            10,  1911  

213| 

254| 

222j 

26Sh 

220 

2491 

2241 

£25,019 
£28.484 
£25,632 
£30,109 
£25,262 
£27,170 
£25,221 

£117    6     5 

July            26        

£lll   16     3 

August         8,     

August        21        

£ll5     6    8 
£ll2     2    9 

£ll4  16     8 

Sf^nteniber  18 

£l08  15    9 

Ontnhpr         ^                 

£ll2    4    4 

E.xports  of  Tin  and  Ore  from  Straits  and  Bolivia. 
Reported  by  A.  Strauss  &  Co. 


Aug.  1911 

Sept.  1911 

1911  to  date 

tons 

tons 

tons 

Metal  from  Straits  to  Europe 

and  America   

4.675 

5148 

39.940 

Metallic  Content  from  Bolivia 

to  Europe 

2.308 

2034 

17.347 

EDITORIAL 


RECENT  HAPPENINGS  on  the  Rand 
point  to  the  desirabihty  of  companies 
supported  by  British  capital  being  compelled 
to  register  in  London,  so  that  shareholders 
may  have  a  reasonable  chance  of  attending 
the  annual  meetings  and  of  exercising  a  healthy 
influence  upon  the  policy  of  the  directors  and 
the  actions  of  the  management.  Frankly,  there 
has  been  too  much  vernukerij  of  late  on  the 
part  of  companies  registered  in  the  Transvaal. 
They  ought  to  register  here. 


FICTITIOUS  figures  of  production,  due 
in  part  to  loose  estimates  made  neces- 
sary by  leaving  gold  in  the  residual  zinc  of 
the  precipitation-boxes,  in  the  form  of  '  zinc 
shorts,'  may  be  avoided  by  using  a  process 
that  allows  a  complete  clean-up  after  precipi- 
tation. If  zinc-dust  be  used  instead  of  zinc- 
shaving,  it  is  possible  to  make  an  accurate 
clean-up,  instead  of  leaving  10  to  30%  in  the 
precipitation-boxes. 


WE  HAVE  REFERRED  previously 
to  the  careless  use  of  the  word  '  tin  '  to 
designate  a  concentrate  consisting  mainly  of 
cassiterite  or  tin  oxide.  Some  of  the  stuff 
shipped  from  Nigeria  carries  only  20%  metallic 
tin,  the  impurity  being  titaniferous  ironstone, 
otherwise  known  as  ilmenite.  Most  of  the 
better  shipments  assay  65%  tin  and  contracts 
with  the  smelters  are  based  on  that  average. 
The  bulk  of  the  Nigerian  output  goes  to  Wil- 
liams, Harvey  &  Co.  and  is  treated  in  their 
works  at  Bootle,  near  Liverpool.  We  under- 
stand that  companies  operating  in  Nigeria  can 
get  the  benefit  of  an  exceptionally  favourable 
contract  made  by  the  Niger  Company  with  the 
tin  smelters  at  Liverpool  and  Cornwall'. 


THE  AMERICAN  MINING  CON- 
GRESS has  postponed  its  annual  session 
from  September  26  to  October  24.  The  place  of 
meeting  is  Chicago,  and  we  understand  that 
the  postponement  has  been  made  at  the  re- 
quest of  President  Taft,  so  as  to  enable  him 
to  deliver  an  address  before  the  Congress  on 
October  28.  A  large  attendance  is  anticipated. 
Undoubtedly  the  Mining  Congress,  which  had 
a  precarious  existence  in  its  youth,  has  steadily 
gained  in  prestige  ;  it  became  an  acknowledged 
force  in  public  affairs  when  it  succeeded  in  its 
advocacy  of  a  Bureau  of  Mines.  This  new 
department  at  Washington  has  already,  under 
the  directorship  of  Mr.  J.  A.  Holmes,  done 
much  useful  work.  As  an  annual  parliament 
for  the  discussion  of  national  mining  affairs 
the  Congress  has  '  made  good.' 


FRANCISCO  I.  MADERO  was  nomin- 
ated president  of  the  Mexican  republic  at 
a  primary  election  on  October  2.  The  general 
election   itself  is  on   October    15,  when   the 
choice   will  undoubtedly   be    ratified.       This 
important  event  received  the  scantiest  mention 
in  the  London  Press  and  was  uniformly  con- 
fused with  the  general  election;  one  paper  pub- 
lished a  portrait  of  the  President,  but  it  was 
that  of  another  man  ;  even  our  most  serious 
newspapers  had  little  to  say.  Yet  the  fact  that 
the  selection  has  been  made,  and  made  without 
disorder,  ratifying  the  revolution  by  choosing 
its  leader,  and  giving  Mexico  once  more  a  con- 
stitutional government,  is  surely  a  matter  of 
worldwide  interest.     General    Madero   is  38 
years  old  on  October  18.     He  has  proved  him- 
self a  man   of  ability  in   business,  including 
that  of  a  smelter.     An  idealist  and  a  reformer, 
he  devoted  his  large  financial  winnings  to  a 
campaign  against  the  despotism  of  Profirio 
Diaz  and  the  corrupt  regime  of  the  cientificos, 
culminating   in  a  revolution   that  started  on 
November  18,  1910,  and  ended  by  the  resig- 


250 


OCTOBER,    1911 


251 


nation  of  Diaz  on  May  25,  1911.  Madero 
became  the  logical  candidate  for  the  presi- 
dency, his  peaceable  election  being  furthered 
by  the  voluntary  exile  of  General  Bernardo 
Reyes,  a  miUtary  leader  who  could  have  made 
trouble  and  for  whose  retirement  the  Mexican 
people  owe  a  signal  debt  of  gratitude.  It  re- 
mains to  be  seen  whether  the  popular  Presi- 
dent can  obtain  such  assistance  from  the  better 
class  of  his  countrymen  as  will  enable  him  to 
give  Mexico  a  stable  and  efficient  government. 
We  believe  that  he  can  ;  we  hope  that  he  will. 


known  bugbear  of  cyaniders  and  by  becoming 
a  factor  in  accelerating  the  East  Rand  break- 
down  it  will  attract  renewed  attention. 


GOVERNMENT  COMMISSIONS  of 
inquiry  in  the  Transvaal  suffered  in 
public  esteem  by  the  ridiculous  performance 
of  one  of  these  official  committees  of  mvesti- 
gation  in  the  case  of  the  Midas  Deep  two 
years  ago,  when  ore  outside  that  company's 
boundaries  and  actually  within  an  unpro- 
claimed  area  was  included  in  the  suppositi- 
tious reserve.  We  are  glad  therefore  that  the 
idea  of  a  Government  commission  was  aban- 
doned in  the  case  of  the  East  Rand  Proprie- 
tary. At  the  present  time  so  many  of  the 
mining  magnates  are  in  politics  in  South  Africa 
that  it  would  be  difficult  to  select  a  commission 
that  would  command  general  confidence. 


IN  DISCUSSING  the  East  Rand  fiasco 
we  have  said  but  little  concerning  the 
trouble  in  the  cyanide  annex,  but  it  will 
be  noted  that  Mr.  Julian's  article  is  highly 
apropos.  As  is  well  known,  lime  is  added  to 
the  banket  ore  in  order  to  neutralize  any 
acidity  due  to  the  oxidation  of  pyrite  and  also 
to  accelerate  settlement  of  slime.  During  the 
recent  spell  of  cool  weather  at  Johannesburg 
it  became  necessary  to  employ  more  than 
the  usual  proportion  of  lime  ;  this  led  to  the 
deposition  of  a  complex  hydrate  of  lime  on  the 
zinc-shaving,  which  thereby  became  inefficient 
in  promoting  the  reaction  that  causes  the  pre- 
cipitation of  the  gold  from  the  enriched  solu- 
tion.    This  detrimental  white  precipitate  is  a 


AMONG  the  articles  in  this  issue  is  one 
on  the  new  system  of  stope-filling,  first 
adopted  in  Silesia,  but  recently  applied  on  the 
Rand  under  the  direction  of  Mr.  Edgar  Pam, 
A.R.S.M.,  who  is  recognized  as  the  chief 
authority  on  the  subject.  His  description  will 
be  appreciated  by  mine  managers  in  other  re- 
gions. We  are  also  fortunate  in  being  able  to 
give  our  readers  a  timely  article  on  obscure 
losses  in  cyanidation  by  Mr.  PL  Forbes  Julian, 
the  joint  author,  with  Mr.  Edgar  Smart,  of  the 
standard  textbook  on  cyanide  practice.  The 
article  itself  has  the  double  merit  of  being  pre- 
pared by  a  specialist  who  also  happens  to  be 
able  to  express  himself  clearly  ;  in  other  words, 
he  has  subjected  his  writing  to  a  process  of 
filtration,  in  which,  however,  a  vacuum  is  con- 
spicuously lacking.  To  us  the  result  appears 
to  be  a  clarified  and  enriched  solution  ready 
for  prompt  precipitation  in  the  mind  of  the 
intelligent  reader. 


GOLD  is  usually  described  as  'fine'  or 
'  coarse  '  without  reference  to  any  re- 
cognized standard.  We  have  seen  two  re- 
ports on  a  Spanish  alluvial  deposit  m  which 
one  engineer  describes  the  gold  as  fine  " 
and  the  other  as  "  coarse,"  from  which  it  might 
be  inferred  that  one  of  them  had  not  seen  it. 
We  commend  the  subject  to  the  standardiza- 
tion committee  of  the  Institution  of  Mining 
and  Metallurgy.  Most  men  of  experience 
will,  we  believe,  agree  in  regarding  particles  of 
gold  as  large  as  No.  8  or  No.  9  shot,  such  as  is 
used  in  shooting  small  birds,  as  '  coarse  '  ; 
this  size  is  about  equal  to  the  head  of  an  or- 
dinary pin ;  although  pins,  of  course,  vary  in 
this  regard.  Something  more  accurate  is  re- 
quired for  technical  use.  Anything  coarser 
would  be  called  small  '  nuggets '  and  any- 
thing smaller  would  be  labelled     fine.'     All 


252 


THE    MINING    MAGAZINE 


coarse  gold  contains  some  '  fine,'  but  truly 
'fine'  gold  is  free  from  'coarse'  particles. 
The  use  of  the  proper  adjective  is  important 
not  only  as  indicating  the  relative  difficulty 
is  saving  the  gold  but  also  as  suggesting  the 
character  of  the  deposit.  Fine  gold  on  the 
top  of  a  placer  may  be  due  to  the  action  of 
a  flood  and  may  indicate  a  purely  superficial 
enrichment;  on  the  other  hand,  coarse  gold 
suggests  concentration  toward  bedrock.  From 
the  paint  gold  of  the  Snake  river,  where  several 
thousand  particles  are  required  to  weigh  a  grain, 
to  the  nuggets  of  the  Klondike,  where  one  piece 
represents  a  month's  wages,  there  is  a  diver- 
sity large  enough  to  encourage  discrimination. 


FULL  PAGE  advertisements  in  the  daily 
Press  invite  the  public  to  find  money  for 
the  New  Northern  Territory  Explorers.  Even 
those  possessed  of  the  least  tenacious  memory 
will  recall  the  scandal  involving  an  earlier 
enterprise  having  a  similar  name.  The  old 
company  was  twice  reconstructed  and  went 
into  voluntary  liquidationin  1909.  Mr.  Horatio 
Bottomley  then  was,  and  now  is,  associated 
with  the  Northern  Terrors,  as  they  are  called 
in  the  market.  His  commendation  of  a  min- 
ing enterprise  need  not  be  taken  seriously. 
The  prospectus  itself,  as  now  issued,  bears 
many  reminders  of  the  one  that  did  duty  in 
1896.  It  is  a  bad  specimen  of  this  kind  of 
document.  We  are  weary  of  saying  that  the 
opinions  of  Government  officials,  and  untech- 
nical  persons  generally,  on  a  mine  are  worse 
than  worthless.  Lord  Kintore,  formerly  Gover- 
nor of  South  Australia,  and  the  Hon.  Charles 
Dashwood,  the  Government  Resident  of  the 
Northern  Territory,  have  no  qualifications 
whatever  for  the  appraisal  of  mines.  The 
use  cf  their  names  is  an  injustice  to  them, 
and  to  the  public.  Nor  do  we  place  much 
faith  in  the  views  of  either  the  Inspector  of 
Mines  or  the  Government  Geologist ;  such 
officials  are  rarely  competent  to  give  the  sort 
of  advice  needed  by  intending  shareholders. 


But  the  chief  testimony  quoted  as  to  the  value 
of  the  mining  claims  is  that  of  Mr.  D.  D. 
Rosewarne,  not  "  late,"  but  long  ago,  Inspec- 
tor of  Mines  for  South  Australia,  who  was 
assistant  manager  to  the  old  company  and  has 
been  promoted  to  director  and  consulting  en- 
gineer of  the  new  one.  He  "  reiterates  his 
view  as  to  the  phenomenal  mineral  wealth  of 
the  territory,"  and  "  pledges  himself  to  justify 
the  expectations  which  were  held  out  a  few 
years  ago."  This  last  reference  to  a  former 
fiasco  is  almost  pathetic,  and  disarms  our  fur- 
ther criticism.  But  we  advise  shareholders 
to  shy  at  anything  "phenomenal."  A  phe- 
nomenon is  an  appearance  ;  it  is  not  a  reality. 
The  prospectus  assures  the  subscribers  that 
they  will  "  also  be  creditors."  They  are  likely 
to  remain  so. 


Zinc  Metallurgy. 

For  some  time  it  has  been  known  by  hear- 
say that  experimental  work  on  a  large  scale  in 
connection  with  the  treatment  of  complex  zinc 
ores  is  being  conducted  at Trollhattan,  Sweden. 
Public  information  regarding  the  process  is 
now  available  for  the  first  time,  owing  to  the 
controllers  of  the  works  seeking  English  and 
German  capital  for  the  purpose  of  continuing 
the  trials  and  enlarging  the  plant.  About  a 
year  ago  the  Norse  Power  &  Smelting  Syndi- 
cate was  formed  in  London  for  the  purpose  of 
taking  an  option  on  various  electric  smelting 
and  power  companies  in  Norway  and  Sweden 
controlled  by  Mr.  Knut  Tillberg.  Mr.  F.  W. 
Harbord  was  instructed  to  make  an  examina- 
tion of  the  process  and  the  works.  His  report 
was  moderately  favourable,  so  the  option  has 
been  exercised,  and  a  company  called  the  Hy- 
draulic Power  &  Smelting  Co.  was  registered 
last  month.  The  capital  is  /"l  ,000,000  in  shares, 
and  ;^875,000  of  debentures  has  been  issued. 
The  whole  of  the  share  capital  (except  seven 
signatory  shares)  and  ;^400,000  in  debentures 
have  been  paid  as  purchase  price  to  Mr.  Till- 
berg and  his  nominees,  as  well  as  ^"100,000  in 


OCTOBER,    1911 


253 


cash  ;  /'475,000  of  debentures  has  been  sub- 
scribed in  England  and  Germany,  and  of  the 
money  thus  raised  ^350,000  will  be  available 
for  extensions  of  plant.  The  negotiations,  the 
technical  examinations,  and  the  organization  of 
the  business  have  been  in  the  hands  of  Messrs. 
Percy  Tarbutt  &  Co.  and  the  financial  mem- 
bers of  their  group.  The  property  acquired 
by  the  company  consists  of  the  entire  share 
capital  of  companies  operating  at  Trollhattan, 
in  Sweden,  and  Sarpsborg  and  Tysse,  in  Nor- 
way, together  with  certain  specified  water- 
rights  and  options  held  by  Mr.  Tillberg.  The 
new  capital  is  to  be  applied,  as  to  ;^100,000, 
for  increasing  the  capacity  of  the  Trollhattan 
works  to  15,000  horse -power,  and,  as  to 
;^250,000,  for  erecting  a  new  plant  at  Tysse 
with  a  capacity  of  from  30,000  to  40,000 
horse-power. 

In  our  '  Precis  of  Technology  '  this  month 
we  give  an  abstract  of  Mr.  Harbord's  report, 
and  we  publish  a  map  showing  the  position  of 
the  various  centres  mentioned.    We  may  state 
briefly  that  the  ore,  after  being  roasted  and 
mixed  with  flux  and  sufficient  carbonaceous 
material  to  reduce  the  oxide,  is  delivered  con- 
tinuously into  a  furnace,  and  that  the  heat  is 
obtained  by  the  resistance  of  the  charge  to  the 
electric  current,  which  enters  by  two  movable 
carbon  electrodes  suspended  through  the  roof 
and  leaves  by   another  electrode  in  the  bed. 
The  zinc  is  volatilized  and  is  caught  as  far  as 
possible  in    the    condensers  in    liquid  form  ; 
most  of  the  lead  and  silver  accumulates  at  the 
bottom  of  the  furnace  ;  while  the  sulphur  left 
in  the  ore  collects  copper  and  iron,  and  forms 
a  matte.     The  actual  reactions  are  more  com- 
plicated than  this,  but  the  outline  is  sufficient 
to  give  a  general  idea  of  the  process. 

In  considering  the  application  of  electricity 
to  the  treatment  of  zinc  ores,  the  efficiency  of 
the  process  and  the  cost  of  the  current  are 
the  two  dominating  factors.  As  regards  the 
latter,  a  furnace  at  Trollhattan  is  rated  at  a 
maximum  of  350  hp.,  and  treats  rather  less 


than  3  tons  of  roasted  ore  per  day.  The  price 
of  a  horsepower-year  is  30s.  3d.,  so  we  may 
take  the  cost  of  current  at  30  shillings  per  day 
when  the  furnace  is  working  at  full  capacity, 
though  the  actual  power  consumed  will  depend 
on  the  nature  of  the  charge.  Mr.  Harbord  re- 
ports that,  in  his  experiments,  550  tons  of 
roasted  zinc-lead  material  was  treated  in  21\ 
days  in  seven  furnaces,  and  that  the  price  paid 
for  power  was  £2^1 .  As  compared  with  the 
cost  of  heating  by  gas  in  the  standard  retorts 
in  Wales,  Belgium,  or  Germany,  where  the 
zinc  works  are  adjacent  to  coalfields,  this 
charge  is  decidedly  high.  When  the  exten- 
sion of  the  works  has  been  effected  according 
to  the  programme  of  the  new  company,  the 
price  paid  for  current  will  naturally  be  re- 
duced. At  the  proposed  works  at  Tysse  it  is 
estimated  that  with  a  plant  generating  30,000 
horse-power,  owned  by  the  company  itself, 
the  cost  of  current  should  be  only  14  shillings 
per  horsepower-year.  Under  such  circum- 
stances the  success  of  the  venture  from  the 
point  of  view  of  cost  of  power  will  be  more 
hopeful.  The  Tysse  installation  will  also  be 
more  favourably  situated  as  regards  freight  on 
foreign  ores,  for  it  will  be  at  tide-water,  thus 
obviating  the  railway  charges  that  form  a 
serious  item  in  the  cost  at  Trollhattan. 

After  carefully  reading  Mr.  Harbord's  re- 
port we  cannot  say  that  we  are  greatly  im- 
pressed with  the  efficiency  of  the  process.  It 
is  admitted  that  the  recovery  of  zinc  is  low, 
and  that  when  complex  argentiferoussulphides 
are  treated  the  average  extraction  is  not  more 
than  60%.  One  great  drawback  is  the  fact 
that  a  large  proportion,  probably  30%,  of  the 
distilled  zinc  is  deposited  as  powder  and  a 
small  amount  also  as  oxide  ;  these  have  to  be 
returned  to  the  furnace  to  form  part  of  a  sub- 
sequent charge.  I  f  the  powder  were  fairly  pure 
zinc,  it  would  require  no  further  treatment 
and  would  be  saleable  for  several  well  known 
purposes.  Unfortunately  it  contains  much 
lead,  and  oxide  of  lead,  so  there  is  no  alterna- 


254 


THE    MINING    MAGAZINE 


tive  but  to  return  it  to  the  furnace.  Thus 
the  cost  of  treatment  per  ton  of  zinc  is  greatly 
increased.  The  zinc  condensed  to  liquid  also 
contains  lead,  and  requires  refining,  which  is 
done  in  other  electric  furnaces.  It  is  claimed 
that  the  refined  zinc  is  unusually  pure  and 
that  it  will  command  an  enhanced  price  in 
the  market,  though  Mr.  Harbord  rightly  re- 
marks that  the  demand  for  this  quality  is 
limited  and  that  any  large  supply  would  an- 
nihilate the  premium.  There  are  losses  of 
zinc,  lead,  and  silver  in  the  slag,  and,  in  ad- 
dition, a  small  amount  of  these  metals  goes 
into  the  matte.  Some  of  the  zinc  and  silver 
is  saved  as  skimming,  and  this  and  the  matte 
require  further  treatment.  Mr.  Harbord  sug- 
gests many  ways  in  which  improvements  can 
be  made.  The  present  cost  of  electrodes  is 
staggering,  amounting  to  ^^204  during  the 
treatment  of  the  550  tons  of  material  already 
mentioned. 

Before  concluding  we  may  mention  two 
further  points.  One  is  that  a  great  many 
other  people  are  experimenting  on  the  same 
lines  and  that  theoretically  their  furnaces 
both  in  principle  and  in  method  of  construc- 
tion are  practically  identical  with  those  at 
Trollhattan,  so  the  relative  skill  of  manipula- 
tion, attention  to  detail,  and  cost  of  power 
will  decide  the  actual  success  of  any  of  these 
rival  processes.  We  may  instance  the  Im- 
bert,  which  is  being  tried  at  the  Hohenlohe 
Huette  in  Germany,  the  Louvrier-Louis  and 
the  Cote-Pierron,  which  are  being  experi- 
mentally used  in  France,  the  Snyder  process 
in  British  Columbia,  and  W.  Mc  A.  Johnson's 
process,  described  in  our  '  Precis  of  Technol- 
ogy '  this  month.  The  Imbert  process  is,  as 
a  matter  of  fact,  under  option  in  London  to  a 
Broken  Hill  group  that  had  previously  backed 
the  present  venture,  and  in  all  probability  we 
shall  hear  something  of  it  publicly  before 
long.  Whether  the  transfer  of  the  interest  is 
due  to  technical  or  stock- exchange  considera- 
tions we  are  unable  to  say ;  from  the  investor's 


point  of  view  we  consider  the  terms  of  the 
present  issue  none  too  attractive. 

The  second  point  to  which  attention  should 
be  drawn  is  that  the  practice  in  zinc  metal- 
lurgy in  retorts  has  been  so  much  improved 
during  the  last  year  or  two  that  the  lead  con- 
tent is  no  longer  a  drawback ;  in  fact,  the 
buyers  desire  to  have  at  least  5%  lead,  for 
this  is  found  useful  in  collecting  the  silver, 
and  the  leady  residue  left  in  the  retorts  is  sent 
to  the  lead  furnace.  It  is  only  recently  that 
we  commented  on  this  new  phase  of  the  zinc- 
lead  problem,  and  we  then  recorded  that  the 
slime  from  Broken  Hill,  if  concentrated  by 
flotation  and  judiciously  mixed  with  the  zinc 
product,  is  profitably  marketable.  It  appears, 
however,  that,  in  negotiations  with  German 
and  Belgian  firms,  all  sorts  of  difficulties  are 
raised,  and  when  the  sale  of  concentrated 
slime  without  admixture  with  zinc  material 
is  proposed  the  terms  and  conditions  become 
impossible.  Thus  the  Broken  Hill  produ- 
cers are  desirous  of  trying  some  alternative 
process  for  the  purpose  of  realizing  the  great 
accumulations  of  slime.  The  Sulphide  Cor- 
poration is  the  only  Australian  producer  that 
is  selling  slime  concentrate  to  the  newly 
formed  firm,  the  others  apparently  waiting  for 
the  Imbert  process  to  become  established.  We 
have  made  these  candid  criticisms  of  this  Nor- 
wegian scheme,  but  we  have  no  hesitation  in 
saying  that  the  venture,  with  its  resources  of 
money,  talent,  and  power,  will  do  great  service 
in  advancing  our  knowledge  relating  to  the  pos- 
sible applications  of  electro-metallurgy. 


Agricola. 

On  another  page  we  publish  an  excerpt 
from  that  celebrated  medieval  book  De  Re 
Metallica,'  by  George  Agricola,  as  translated 
by  Mr.  and  Mrs.  H.  C.  Hoover.  Even  the 
few  paragraphs  that  we  quote  afford  an  in- 
teresting comment  on  mining  affairs  as  viewed 
by  an  authority  who  lived  and  wrote  four  hun- 
dred years  ago.     The  good  sense  and  quiet 


OCTOBER,    1911 


255 


humour  of  the  ancient  writer  will  appeal  to 
those  who  have  taken  an  interest  in  the  recent 
discussion  on  speculation  as  a  factor  in  the 
business  of  mining.  Apparently  the  essential 
human  frailties  of  those  that  operate  mines 
remain  the  same  although  the  mdustry  itself 
has  undergone  vast  changes.  It  is  interesting 
also  to  note,  from  this  single  quotation,  that 
the  idea  of  risk  and  of  returns  proportioned  to 
the  chances  of  a  hazardous  financial  opera- 
tion, was  firmly  fixed  in  Agricola's  m.ind, 
which  grasped  the  basic  factors  in  1556  better 
than  some  of  our  friends  in  1911.  He  refers 
to  trickeries  that  have  survived  even  to  this 
enlightened  period  of  the  world's  history,  but 
the  old  commentator  takes  a  cheerful  view 
and  concludes  that  such  divagations  are  not 
inherent  in  the  industry,  for  mining  is  a  call- 
ing of  peculiar  dignity." 

Agricola,  whose  great  work,  the  '  De  Re 
Metallica,'  was  published  after  his  death  in 
1555,  was  a  scientific  man  in  the  broadest 
sense  of  the  word,  and  he  deserves  his  high 
rank  among  those  to  whom  is  due  not  only 
the  advance  of  systematic  mining  and  metal- 
lurgy but  of  science  in  general.  He  was  the 
first  to  make  scientific  deductions  from  care- 
fully collected  data  and  he  was  the  first  to 
breakaway  from  the  superstition  of  the  Middle 
Ages.  To  him  the  science  of  geology  owes 
the  first  explanation  that  the  earth's  crust  is 
built  largely  out  of  water  deposits  ;  that  the 
configuration  of  its  surface  is  due  to  volcanic 
action  and  erosion  ;  and  that  orebodies  are  the 
result  of  deposition  by  water  in  open  spaces 
within  the  rocks.  The  science  of  mineralogy 
owes  to  him  the  first  attempt  at  a  rational 
classification  of  minerals,  and  the  first  descrip- 
tion of  bismuth  and  cobalt.  To  him  the  science 
of  chemistry  is  indebted  for  the  first  textbook 
on  assaying  and  for  a  description  of  over  a 
hundred  different  processes,  of  which  less  than 
one  half  had  been  mentioned  previously  in 
writing.  Finally,  to  Agricola  the  miner  owes 
the  first  account  of  underground  methods  and 


machinery,   and   the    first    textbook    on    sur- 
veying. 

Agricola  was  by  birth  a  German,  his  real 
name  being  Bauer.  He  was  exceptionally 
well  educated,  having  studied  at  Leipzig  and 
at  several  Italian  universities.  Moreover,  he 
was  not  only  a  mining  engineer  in  the  widest 
sense  of  the  term,  but  also  a  mine -owner, 
having  made  a  competence  through  partici- 
pation in  the  operation  of  a  mine  in  the  Saxon 
Erzgebirge.  His  works  were  written  in  Latin, 
and  not  of  medieval  character  but  of  the  most 
classic  style  ;  they  have  been  translated  into 
German  and  Italian,  passing  through  many 
editions  and  constituting  the  backbone  of  min- 
ing literature  for  at  least  two  centuries.  Our 
readers  will  be  interested  to  learn  that  a  trans- 
lation of  the  '  De  Re  Metallica  '  has  been 
made  by  Mr.  and  Mrs.  H.  C.  Hoover,  after 
several  years  of  laborious  effort  snatched  from 
amid  the  manifold  occupations  of  a  busy  life. 
We  betray  no  secret  in  saying  that  Mrs. 
Hoover  is  a  graduate  in  science  from  the 
same  college  as  her  husband,  namely,  the  Le- 
land  Stanford  university  in  California.  We 
are  glad  to  say  that  the  text  of  the  translation 
is  in  the  hands  of  the  printers  ;  as  considerable 
progress  has  been  made  in  the  necessary  an- 
notation, it  is  hoped  to  issue  the  volume  early 
next  year.  The  book  is  to  be  reproduced  in 
its  original  form,  the  illustrations  appearing  in 
facsimile,  with  a  biography  of  the  author  and 
a  complete  annotation,  bringing  the  history  of 
the  allied  sciences  down  to  Agricola's  period. 
In  view  of  the  fact  that  Agricola  wrote  con- 
cerning these  sciences  a  thousand  years  after 
the  language  used  by  him  had  ceased  to  de- 
velop, he  was  compelled  to  employ  innumer- 
able adaptations  in  order  to  describe  the  com- 
plex subjects  of  which  he  treated.  Therefore, 
while  the  English  translation  of  the  book  has 
been  attempted  by  numerous  Latin  scholars, 
hitherto  they  have  abandoned  the  task  as  soon 
as  they  realized  their  inability  to  understand 
the  text.      It  is  a  case  where  the  translator  to 


256 


THE    MINING    MAGAZINE 


be  successful  must  not  only  possess  a  know- 
ledge of  the  particular  sciences  involved  but 
be  willing  to  devote  the  time  necessary  for  a 
comprehensive  study  of  metallurgy  and  the 
allied  arts  in  the  Middle  Ages,  as  obtainable 
from  other  sources;  mere  transliteration  would 
not  suffice  to  give  the  modern  reader  an  in- 
forming appreciation  of  this  venerable  volume. 
The  English  version  of  Agricola  should  be  of 
the  greatest  interest  to  mining  engineers  es- 
pecially, and  to  scientific  folk  generally,  in 
affording  a  clue  to  the  origin  of  many  techni- 
cal methods  and  scientific  ideas.  To  the 
translators  we  extend  hearty  congratulations 
on  an  achievement  of  the  first  rank. 


Prestea. 

It  is  a  pity  to  belabour  any  single  episode, 
or  "to  chew  the  rag  "  as  the  Americans  say, 
but,  on  the  other  hand,  it  is  desirable  to  get 
at  the  truth  of  disagreeable  incidents  with  a 
view  to  obtaining  guidance  in  mining  affairs. 
We  referred  to  the  Prestea  affair  last  month 
and  commented  upon  the  hiatus  between  the 
chairman  and  the  manager,  the  one  stating  at 
the  general  meeting  that  the  mine  could  sup- 
ply 30,000  tons  for  the  110-stamp  mill  when 
completed,  at   the   end  of  the  current  year, 
while  the  manager  in  a  letter  to  the  board  of 
directors  asserted  that  it  would  be  impossible 
to  hoist   more   than    15,000  tons  of  ore  per 
month  "  through    the    existing   shafts."     To 
the  comment  then  made  we  have  to  add  an- 
other paragraph  based  on  further  information. 
The  simple  fact  is  that  the  chairman  and  the 
manager  did  not  compare  notes,  Us  netaient 
pas  d'accord.     Mr.  E.  C.  Homersham  took 
charge   in    January,   succeeding   Mr.  Walter 
Broadbridge.      The  chairman,  Mr.   Edmund 
Davis,  who  naturally  knows  more  about  mar- 
kets than  mines,  prepared  his  speech  and  sub- 
mitted it  to  the  consulting   engineer   of  the 
Central    Mining,   late    Wernher-Beit,   group. 
That  gentleman  glanced  over  it  cursorily  and 
gave  it  his  imprimatur.      At  that  time   the 


mine   manager   was  about  to  start   from   the 
Gold   Coast  for  a  holiday  in   England.     Mr. 
Davis  made   his  speech  and  greatly  pleased 
the  shareholders.     He  asked  them  to  "  bear 
in  mmd  "  the  fact  that  "  with  the  110  stamps 
and  the  plant  connected  therewith — the  erec- 
tion of  which  was  being  gradually  completed 
— the  company  should  be  able  to  treat  30,000 
tons  per  month."     With  this  equipment  "  the 
profits  should,  if  all  went  well,  be  at  the  rate 
of  ;^20,000  to   ^25,000  per   month,   and   he 
(Mr.    Davis)    trusted    that    they   (the    share- 
holders) would  be  satisfied  with  the  forecast 
he  had  outlined,  as  he  felt  confident   that  it 
would.be  realized."     In  reply  to  a  question 
he  removed  any  doubt  that  might  have  linger- 
ed  by  saying:  "As  to  the    110  stamps,  the 
directors  believed  that  the  full  plant  would 
be  at  work  in  November  or  December  next, 
but  it  was  absolutely  impossible  at  the  mo- 
ment to  definitely  fix  a  date."     It  always  is 
impossible  to  fix  a  date  when  a  new  plant 
will  start,  for  delays  are  proverbial,  but  it  is 
possible  to  know  whether  a  mine  can  make 
an  output  of  30,000  tons  or  only  half  that  ton- 
nage.    Unfortunately   the  manager    did   not 
read  the  account  of  the  meeting  and  was  even 
unaware  of  the  task  allotted  to  him  until  inci- 
dentally a  conversational  reference  was  made 
to  the  matter   by   the  chairman  in    August. 
This,  of  course,  caused  some  perturbation  and 
necessitated  the  circular  issued  by  the  secre- 
tary  on  September   1,   correcting  the   error. 
All  of  which  shows  a  slackness  of  administra- 
tion that  is  simply  astounding.     We  under- 
stand   that    Mr.    Miles    Sharp,   of    the    New 
Modderfontein,  will   be  sent  by    the  Central 
Mining  group  to  ascertain  what  the  Prestea 
can  do  and  what  it  cannot  do.    His  report  will 
be  awaited  with  keen  interest.     Incidentally, 
it  may  be  added  that  the  annual  report  of  the 
directors,  issued  in  June,  does  not  give  the 
estimates  of  output  and  profit  furnished  by 
the  chairman  at  the  meeting,  but  it  does  say 
that  "  the  erection  of  the   110-stamp  mill   is 


OCTOBER,    1911 


257 


progressing  as  rapidly  as  possible."  It  seems 
only  reasonable  for  a  shareholder  to  infer 
that  the  110-stamp  mill  was  being  erected  to 
crush  ore  and  that  it  would  be  supplied  with 
ore  to  its  full  capacity.  The  unusual  num- 
ber of  the  stamps  is  due  to  the  fact  that  the 
complement  includes  the  original  60-stamp 
mill  and  one  of  50  stamps  acquired  from  the 
Attasi  Mines  Ltd.,  a  defunct  enterprise  that 
operated  60  miles  from  the  Prestea.  At  the  mine 
it  is  stated  that  if  30,000  tons  could  be  hoisted, 
the  crushers  could  not  treat  such  a  tonnage, 
and  if  the  crushers  could  do  so,  the  aerial 
tramway  would  be  incapable  of  transporting 
it.  Additional  equipment  to  the  tune  of 
;^150,000  is  required  before  the  optimistic 
programme  of  the  chairman  can  be  made  a 
cheerful  reality. 


East  Rand  Proprietary. 

The  fiasco  acknowledged  on  September  2 
has  not  received  any  official  explanation  as 
yet.  The  cryptic  circular  of  the  company, 
the  bald  and  unconvincing  statements  of  the 
chairman,  and  the  untechnical  comment  of 
the  financial  Press  have  all  served  but  to  leave 
confusion  worse  confounded.  On  September 
22  it  was  announced  from  Johannesburg  that 
the  Government  would  appoint  a  committee 
of  investigation  "  with  a  view  to  discovering 
the  cause  of  the  leakage."  This  committee 
was  to  consist  of  Mr.  R.  N.  Kotze,  Govern- 
ment Mining  Engineer,  Mr.  J.  G.  Lawn,  for- 
merly professor  in  the  South  African  School 
of  Mines  and  Technology,  but  now  consulting 
engineer  to  Barnato  Bros.,  and  Mr.  P.  Ross 
Frames,  the  managing  director  of  the  Premier 
Diamond  company.  On  the  26th,  an  official 
notice  was  published  at  Pretoria  stating  that 
a  commission  had  been  appointed  to  enquire 
into  the  situation  of  the  East  Rand  Propri- 
etary Mines  "  ;  this  commission  consists  of 
two  magistrates  and  the  Government  Mining 
Engineer.  Thus  the  representatives  of  the 
bench  replaced  those  of  high  finance,   with 


Mr.  Kotze  as  a  tertium  quid.  Next  day  an 
application  was  made  by  the  Company  for  an 
interdict  restraining  the  Commissioners  from 
proceeding  with  the  enquiry,  on  the  ground 
that  the  ordinance  under  which  the  Govern- 
ment purported  to  act  did  not  warrant  an  in- 
vestigation of  private  affairs  and  that  the 
proper  procedure  was  a  private  enquiry  under 
Section  96  of  the  Companies  Act  (Transvaal), 
which  corresponds  with  Section  109  of  the 
English  Consolidated  Companies  Act.  Under 
this  section  a  Minister  may,  on  application 
from  shareholders  holding  an  aggregate  of  not 
less  than  one  tenth  of  the  shares,  appoint  in- 
spectors to  investigate  the  company's  affairs^ 
with  power  to  examine  its  officers  and  agents 
under  oath.  This  protest  succeeded,  for  on 
the  28th  the  solicitors  representing  the  Gov- 
ernment and  the  Company  signed  an  agree- 
ment whereby  an  application  was  to  be  made- 
in  accordance  with  the  company  law  quoted 
above.  The  Company  guarantees  the  cost 
of  the  enquiry  and  authorizes  the  Minister  of 
Mines  to  publish  a  report  embodying  the  re- 
sults of  the  enquiry,  the  Government  with- 
drawing the  notice  appointing  its  own  Com- 
mission. On  September  23  it  was  stated  that 
Mr.  W.  A.  Caldecott  had  ascertained  that  the 
slime  plant  was  overloaded,  so  as  to  require 
the  addition  of  10  vats  and  one  tube-mill, 
thus  confirming  the  information  previously 
published  in  our  last  issue.  On  the  same 
day  Sir  George  Farrar  sailed  for  Cape  Town 
on  his  way  to  Johannesburg  with  the  avowed- 
purpose  of  investigating  the  circumstances 
surrounding  the  temporary  loss  of  gold  at  the 
reduction  works  "  of  the  East  Rand  Propri- 
etary. In  an  interview  published  in  South 
Africa  the  chairman  of  the  East  Rand  talked 
to  a  reporter  without  giving  any  information 
beyond  a  general  intention  shortly  "  to  satisfy 
and  reassure  "  the  shareholders.  On  Sep- 
tember 27  a  rumour  that  the  mill  was  about 
to  be  closed  down  caused  a  further  relapse  in 
share  quotations,  to  3t«.     Next  day  the  Lon- 


258 


THE    MINING    MAGAZINE 


don  sub-office  of  the  Company  published  a 
cablegram  from  its  Johannesburg  headquarters 
stating  that  this  rumour  was  unfounded  and 
that  work  was  proceeding  satisfactorily,  150,000 
tons  of  6"9  dwt.  ore  having  been  crushed  up 
to  September  26.  To  complete  the  story  of 
this  unfortunate  episode,  it  remains  to  state 
that  as  early  as  January  last  a  bet  was  made 
that  East  Rands  would  go  to  75s.  before  Sep- 
tember ;  it  is  a  fact  that  what  is  known  on 
the  market  as  the  clever  brigade  sold  East 
Rands  consistently  during  the  first  six  months 
of  the  present  year  :  also  it  is  generally  under- 
stood that  the  Anglo-French  Exploration  Co., 
with  a  board  that  includes  many  of  the  gentle- 
men directing  the  East  Rand  Proprietary, 
sold  its  holding  long  before  any  acknowledg- 
ment was  made  that  affairs  had  gone  wrong. 
These  sinister  facts  afford  an  appropriate 
background  for  an  episode  that  has  seriously 
shaken  public  confidence  in  Rand  mining  en- 
terprises. 

In  order  to  understand  the  technical  aspect 
of  the  case,  it  is  necessary  to  explain  that  the 
East  Rand  reduction  works  consist  of  four 
mills,  ranging  in  age  from  14  to  4  years,  and 
varying  so  much  in  their  design  as  to  illus- 
trate the  recent  growth  of  local  metallurgical 
practice.  Similarly  the  mines  consist  of  di- 
verse units  in  varying  stages  of  development. 
Both  mines  and  mills  were  placed,  by  the 
consolidation  of  companies,  under  one  com- 
plex management  having  most  of  the  defects 
and  few  of  the  benefits  expected  from  an 
amalgamation  of  interests.  The  act  of  con- 
solidation was  followed  by  the  promulgation 
of  an  ambitious  programme  and  the  promise 
of  a  production  proportioned  to  the  optimistic 
views  of  the  chairman  and  his  friends.  The 
management  received  orders  to  increase  the 
output  to  a  tonnage  permitting  of  dividends 
at  the  rate  of  40%  on  ;^2,500,000,  which  is 
the  nominal  capital  of  the  enterprise.  Only 
as  lately  as  May  Sir  George  Farrar  stated  at 
the  annual  meeting  that  dividends  at  this  rate 


could  be  maintained.  But  they  could  not  be 
maintained  at  40%.  The  chairman  ought  to 
have  known  it,  if  he  did  not.  Those  in  charge 
of  the  mines  and  mills  certainly  knew  it,  for 
they  were  hopelessly  trying  to  perform  the 
impossible  while  well  informed  speculators  in 
London  and  at  Johannesburg  were  selling 
their  own — and  other  people's — shares  with 
the  foreknowledge  that  a  breakdown  was  in- 
evitable. 

The  trouble  in  the  mill  does  not  explain  the 
fiasco ;  it  is  true  a  difficulty  with  the  cyanide 
solution  did  hinder  efficient  extraction,  but  that 
was  only  a  symptom  of  the  inefficiency  due  to 
an  attempt  to  exceed  the  real  capacity  of  the 
mill,  and  of  the  mine.  The  discrepancy  in 
the  mill-returns  became  manifest,  it  is  said, 
as  early  as  last  November.  It  began  even 
earlier.  The  effort  to  force  the  pace  had 
failed  more  than  a  year  ago,  and  all  the  sub- 
sequent efforts  were  unavailing.  When  the 
yield  began  to  fall  short  of  the  figure  required 
by  the  official  programme,  those  in  charge 
covered  the  shortage  by  adjusting  the  re- 
turns. This  can  be  done  in  many  ways,  from 
trespassing  on  a  reserve  of  bullion  to  simple 
manipulation  of  figures.  Our  information  in- 
dicates that  when  the  yield  was  seen  to  be 
inadequate  it  was  improved  by  postponing 
the  clean-up  for  a  day  or  two,  in  the  expecta- 
tion, of  course,  of  making  a  commensurate 
gain  during  the  ensuing  month.  When  this 
proved  impossible  and  the  discrepancy  be- 
came still  greater  it  is  likely  that  more  days 
were  borrowed  from  the  following  month, 
and  that  this  discounting  of  the  future  went 
on  until  the  difference  could  no  longer  be  ob- 
scured. A  day  of  accounting  came,  and  with 
it  all  sorts  of  vague  explanations  with  a  view 
to  allaying  the  anxiety  of  shareholders.  The 
causes  that  led  to  poor  extraction  in  the  cya- 
nide annex  will,  we  presume,  be  explained 
and  rectified  ;  but  they  are  only  a  symptom 
of  the  underlying  trouble.  In  order  to  make 
the  enormous  production  required  to  pay  a 


OCTOBER,    1911 


259 


profit  proportioned  to  the  market  valuation  of 
the  mine,  that  is,  to  furnish  dividends  at  the 
rate  of  40%  on  a  capital  of  ;^2,500,000,  it  was 
necessary  to  increase  the  output  of  ore  from 
156,000  tons  per  month,  as  it  was  in  Febru- 
ary of  last  year,  to  202,400  tons,  as  it  was  in 
July  of  this  year.     The  bigger  duty  of  the 
mills  was  supplemented  by  additional  equip- 
ment, such  as  new  amalgamating  plates  and 
cyanide  vats,  all  of  which  entailed  some  ab- 
sorption of  gold.     Moreover,  such  additions 
to  the  plant  as  were  made  proved  inadequate, 
for  the  number  of  vats  and  other  mill-parts 
was  not  properly  proportioned  at  the  start,  so 
that  the  cyanidation  became  inefficient  to  the 
point  of  entailing  a  loss.     The  correspondent 
of  The  Times  says  it  was  13,000  ounces,  and 
gives  that  as  the  full  measure  of  the  deficit ; 
as  if  a  loss  of  ^52,000  worth  of  gold  were 
adequate  explanation    for    a    depreciation   of 
/"6, 250, 000  in  the  value  of  the  property,  the 
shares  falling  from  5f  to  3i.      Despite  all  the 
official  protestations  it  seems  inevitable  that 
the  capacity  of  the  mine,  as  well  as  of  the 
mill,  is  a  factor  in  the  problem.     When  the 
output  of  ore  was  being  raised  from  156,000 
to  200,000  tons  per  month  it  became  neces- 
sary to  press  the  stoping.     This  entailed  the 
breaking  of  low-grade  stuff.     A  manager  who 
is  told  to  make  a  profit  in  excess  of  the  nor- 
mal capacity  of   his  mine   will   either  select 
rich    stopes   or   increase  the    tonnage.     The 
latter  plan  was  adopted  ;    of  course,   it   was 
accompanied  by  a  decline  in  grade,  which  it 
was  hoped  to  rectify  slowly  by  sorting  as  the 
tonnage  increased.     On  paper,  the  manage- 
ment confirmed  the  chairman's  promises,  aug- 
menting the  output  progressively  and  main- 
taining for  several  months  a  yield  of  5*9  dwt. 
from  6'6  dwt.  ore  as  against  an  average  of 
6'5  dwt.  from  7  dwt.  ore  during  the  whole  of 
last  year.     Sorting  declined  from  875%,  the 
average  amount  of  waste  rejected  in  1910,  to 
5%  in  August  1911.    The  management  carried 
out  the  programme  on   paper,  but  they  were 


unable  to  exceed  the  capacity  of  their  mines 
and  mills ;  they  fell  behind  ;  they  smothered 
the  truth,  hoping  to  'catch  up,'  but  they  failed 
to  do  so,  because  the  poor  precipitation  in  the 
zinc-boxes    proved   a    culminating   handicap- 
Finally  they  threw  up  their  hands  and   an- 
nounced a  discrepancy.     Obviously,  the  sud- 
den decrease  of  profit  announced  for  August 
is  the  acknowledgment  not  of  a  catastrophe 
in   that  particular   month   but   of  cumulative 
errors    in    the    returns    issued    during    many 
months.     The  fiasco  is  the  result  of  an  opti- 
mistic programme  that  taxed  the  resources  of 
the  mines  and  mills  to  the  breaking  point  ;   it 
indicates  a  serious  error  of  judgment.    It  does 
not  mean  that  the  consolidated  mines  are  in- 
capable  of    making   a   steady    production  of 
200,000   tons   monthly,   if    sufficient    time  is 
given  to  prepare  them   for  such   a  perform- 
ance ;  nor  does  it  mean  that  the  mills  cannot 
be  readjusted  and  equipped  for  the  treatment 
of  such  an  output.      It  does  mean  that  up  to 
date  the  capacity  of  the  mines,  mills,  and  the 
management,  of  the  East  Rand  Proprietary 
has  been  over-estimated  by  about  25  per  cent. 


Grinding  Machines. 

It  is  announced  from  Johannesburg  that 
the  Mines  Trials  Committee  has  rejected  the 
Giesecke  mill,  having  ascertained  that  it  did 
not  fulfil  the  guarantee  made  as  to  efficiency. 
Until  that  committee's  report  is  published  the 
points  of  weakness  will  not  be  fully  known, 
but  we  have  already  indicated,  in  our  August 
issue,  that  the  wear  and  tear  is  excessive,  due 
probably  to  the  use  of  liners  to  which  springs 
are  attached.  However,  the  experiments  with 
this  device  and  the  attention  drawn  to  them 
will  serve  a  decidedly  useful  purpose.  As  Sir 
Henry  Roscoe  used  to  say,  when  a  lecture 
demonstration  failed  to  yield  the  expected 
chemical  reaction  :  "  Though  the  experiment 
did  not  succeed,  the  principle  remains  the 
same."  Undoubtedly  the  principle  of  the 
ball-mill  crushing  remains  one  to  which  prac- 


260 


THE   MINING  MAGAZINE 


tical  mechanical  engineers  will  do  well  to  give 
renewed  attention.  The  tube-mill  has  come 
to  stay,  and  its  older  step-brother,  the  ball- 
mill,  is  destined  to  be  resuscitated  vigorously 
and  effectively.  This  has  already  happened 
at  Kalgoorlie,  a  metallurgical  centre  worthily 
known  for  enterprise  and  originality.  The 
coarse  crushing  of  the  ore  by  stamps  involves 
a  delay  in  the  discharge  of  the  product,  while 
the  ball-mill  type  of  grinder  ejects  the  ore  as 
soon  as  it  has  been  reduced  to  a  given  size. 
This  is  the  fundamental  difference  between 
them.  Whether  a  ball-mill  and  a  tube-mill 
in  tandem  is  an  effective  arrangement  may  be 
questioned.  The  speed  at  which  the  ball-mill 
is  revolved  is  not  likely  to  be  conducive  to  a 
maximum  of  efficiency  on  the  part  of  the  tube- 
mill  portion  of  the  arrangement.  Moreover, 
the  two  portions  of  the  machinery  represent 
two  stages  of  grinding  and  it  may  prove  ad- 
vantageous to  size  the  ore  particles  between 
these  two  stages  with  a  view  to  returning  the 
over-size  for  further  preliminary  comminution. 
In  the  meanwhile  enterprising  mill-men  will 
look  with  renewed  interest  at  Chilean,  Krupp, 
and  Hardinge  mills,  with  their  variations  on 
the  same  principle.  As  a  page  from  experi- 
ence we  note  the  article  by  Mr.  J .  W.  Hutchin- 
son, the  superintendent  of  the  Goldfield  Con- 
solidated mill,  in  Nevada ;  in  that  valuable 
record,  as  published  by  the  Mining  and  Scien- 
tific Press,  it  is  stated  that  an  addition  of  40 
stamps,  3  tube-mills,  and  25  concentrators  was 
under  consideration.  But  this  involved  a  large 
increase  of  floor -space,  structural  steel  for 
building,  and  enorm.ous  concrete  foundations. 
Also  it  entailed  a  delay  of  six  months,  with  an 
additional  expenditure  of  $175,000.  As  an 
alternative  it  was  decided  to  use  six  Chilean 
mills  between  the  existing  stamps  and  tubes. 
The  battery- screens  were  changed  for  12-mesh 
to  4-mesh  and  a  duty  of  8|  tons  was  obtained, 
followed  by  classification  of  the  product,  the 
over-size  being  fed  to  the  Chilean  mills,  dis- 
charging through  16-mesh  screens  and  deliver- 


ing, after  further  classification,  to  the  tube- 
mills.  This  arrangement  saved  3  months  in 
time  and  $100,000  in  money.  No  additional 
building  was  required,  yet  the  alteration  in- 
creased the  capacity  of  the  plant  by  40%.  We 
commend  this  episode  as  a  suggestive  applica- 
tion of  re-grinding  machinery  before  cyani- 
dation. 


Deep  Mining  at  Bendigo. 

The  mines  of  the  Rand  appear  destined  to 
have  undisputed  claim  to  maximum  depth,  as 
well  as  aggregate  productiveness,  for  the  deep 
mines  of  Bendigo  have,  one  by  one,  been 
forced  to  cease  operation  at  the  lowest  levels. 
Twenty  years  ago  a  dozen  mines  on  the  New 
Chum  lode,  which  is  the  anticlinal  axis  of  a 
series  of  saddle  reefs,  could  claim  to  have  the 
deepest  shafts  of  any  gold  mines  in  the  world. 
At  that  time  Lansell's  180  mine,  with  a  depth 
of  2650  feet,  was  the  pioneer.  Since  then  the 
persevering  miner  has  gone  to  4614  feet,  this 
being  the  greatest  depth  attained  by  the  shaft 
of  the  Victoria  Reef  Quartz  mine.  Owing  to 
a  withdrawal  of  financial  support  by  the  re- 
presentatives of  the  Lansell  Estate,  the  chief 
contributor,  the  work  was  stopped,  despite  a 
grant  by  the  Mines  Department  of  a  subsidy 
on  the  basis  of  sharing  the  expense  equally. 
The  objective  was  the  saddle  formation  cut  in 
the  neighbouring  New  Chum  Railway  mine  at 
4154  feet,  which,  allowing  for  the  pitch  of  the 
orebody,  would  bring  it  into  the  Victoria  Reef 
Quartz  claim  at  about  4800  feet.  All  the  deep 
mines  on  the  New  Chum  line  have  ceased 
operation,  the  deepest  work  in  progress  now 
being  at  1100  feet  in  the  Ironbark  mine,  some 
distance  north  of  the  famous  group  on  the 
north  and  south  slopes  of  Victoria  Hill,  where 
Ballestedt  and  Lansell  first  proved  the  vertical 
persistence  of  the  saddle-reef  formation  forty 
years  ago.  The  orebody  cut  by  the  New  Chum 
Railway  at  4154  feet  gave  an  average  yield  of 
62  dwt.  per  ton,  hence  the  effort  to  intercept  it 
at  a  greater  depth  indicates  the  pluck  charac- 


OCTOBER,    1911 


261 


terizing  our  old  friends  at  Bendigo.  We  doubt 
whether  much  has  been  lost,  in  an  economic 
sense,  by  the  decision  to  stop  sinking.  It  is 
our  opinion  that  the  mining  companies  at  Ben- 
digo have  been  playing  a  losing  game  ever 
since  they  operated  at  a  depth  of  over  half  a 
mile  ;  some  ore  has  been  found  and  some  divi- 
dends have  been  paid,  but  not  nearly  enough 
to  compensate  the  losses.  Deep  mining  has 
its  own  fascination,  but  the  experienced  miner 
in  his  introspective  moments  will  confess  that 
the  big  winnings  are  usually  made  nearer  the 
sunlit  surface.  At  Bendigo  the  big  bonanzas 
were  largely  in  the  zone  between  500  and  2000 
feet.  We  note  with  pleasure  that  lateral  pros- 
pecting at  shallower  levels  is  now  the  fashion 
at  Bendigo  and  that  a  systematic  effort  is  being 
made  to  test  the  intermediate  anticlinal  axes 
parallel  to  the  main  lines  of  reef.  This  is  a 
policy  recommended  by  the  present  writer  20 
years  ago. 


The  Generosity  of  Science. 

Knowledge,  especially  that  part  of  it  rela- 
ting to  technology,  grows  by  the  accretion  of 
experience.  We  do  not  live  by  ourselves, 
much  less  do  we  perform  professional  work 
in  isolated  units ;  on  the  contrary,  co-opera- 
tion is  an  essential  factor  of  success.  Such 
generalizations  are  prompted  by  observing  the 
curiously  anti-social  efforts  of  technical  men 
to  solve  problems  on  their  own  account,  with- 
out any  serious  attempt  to  ascertain  whether 
others  may  not  have  encountered,  and  over- 
come, similar  difficulties  elsewhere.  For  ex- 
ample, at  the  Dharwar  Reefs  in  India  and  at 
the  Ashanti  Goldfields  m  West  Africa  the 
presence  of  graphite  interferes  with  amalga- 
mation ;  at  the  Lancefield  mine  in  W^estern 
Australia  both  arsenic  and  graphite  hinder  the 
extraction  of  gold  in  the  ore,  at  the  San  Fran- 
cisco del  Oro  in  Mexico  the  refractory  ele- 
ment is  arsenic,  and  at  the  Suan  mine  in 
Korea  the  gold  and  copper  are  associated  wath 
bismuth,  which  renders  the  ore  refractory.  As 


to  the  last  of  these  we  count  with  perfect  con- 
fidence in  seeing  the  details  published  at  an 
early  date,  in  our  own  columns  or  in  those  of 
a   worthy    contemporary,   for    we    know   the 
generous  temper  of   Mr.   H.  Collbran,   who 
controls  the  operations  of  the  Suan  mine.   As 
for  the  other  four  mines  mentioned,  we  have 
no  reason  to  impute  any  littleness  of  spirit  to 
the  management,  but  we  may  be  forgiven  for 
anticipating  the  argument  that  the  information 
available  is  as  yet  inconclusive,  and,  such  as 
it  may  be,  it  is  the  property  of  the  company 
at  whose  expense  it  was   obtained,  and  not 
that  of  the  public,  whether  technical  or  lay. 
An  example  of  a  more  generous  spirit  is  af- 
forded by  the  directors  of  the  Globe  &  Phoenix 
mine,  in  Rhodesia,  by  whose  permission  Mr. 
H.  T.  Brett  was  enabled  to  publish  an  account 
of  his   successful  experiments  in  treating  an 
ore  rendered  difficult  by  the  presence  of  anti- 
mony in  the  form  of  stibnite.     We  shall  be 
surprised  if  this  publication  does  not  lead  to 
an  exchange  of  ideas  and  experience  with  other 
metallurgists  to  whom  antimony  has  at  other 
places  proved  a  bugbear.  We  know  of  what  we 
speak,  for  this  very  result  has  followed  from 
similar  publicity,  notably  in  the  discussions 
relating  to  pyrite  smelting,  sampling  of  ore, 
and  cyanide  practice  generally.     If  directors 
will   recognize  that  the  frank   give-and-take 
among  technical  men  can  do  no  harm  and  is 
likely  to  be  of  mutual  good  service,  they  will 
encourage  the  members  of  their  staff  to  record 
their  experience,  and  thereby   contribute  to 
the  improvement  of  mining  and  metallurgical 
methods. 

An  appeal  may  be  made  to  the  officials  of 
companies  on  the  narrow  ground  of  enlightened 
selfishness,  such  as  is  essential  to  the  success 
of  corporate  affairs.  We  hazard  the  state- 
ment that  neither  graphite  nor  arsenic,  neither 
bismuth  nor  antimony,  as  an  obstacle  to  the 
treatment  of  gold  ore,  is  anything  new  ;  on 
the  contrary,  the  same  trouble  in  different 
guise,  it  may  be,  has  been  faced  by  millmen 


262 


THE    MINING    MAGAZINE 


and    metallurgists    at    other    localities.     The 
gentlemen  in  India  and  Rhodesia,  in  Mexico 
and    West    Africa,    may    have    discovered  a 
remedy   better   than    any   heretofore    found ; 
and  they  may  not.   It  would  be  well  for  them 
to  ascertain  what  others  have  done  and  begin 
by  describing  their  own  experiments,  even  if 
abortive.  There  is  no  greater  mistake  than  to 
suppose  that  only  the  successful  experiment  is 
valuable  and  worth  recording.     It  is  worth 
while  to  indicate  to  others  the  paths  of  inves- 
tigation that  lead  nowhere,  so  as  to  save  fruit- 
less search  ;    it  may  prove  advantageous  to 
describe  a  failure  for  the  sake  of  the  hint  that 
turns  failure  into  success  ;   it  is  not  a  barren 
duty  to   record  efforts   in  one  direction  that 
may  throw  light  even  in  an  opposite  direc- 
tion.     To  professional  men  we   can  appeal 
without  hesitation,  for  we  know  that  most  of 
them  have  discarded  the  pitiful  idea  that  to 
give  away  information  is  to  squander  a  stock 
in  trade ;  on  the  contrary,  the  best  of  them 
know  well  that  to  do  a  thing  oneself  is  an 
experience  quite  distinct   from   reading  how 
another  has  done  it  and  that  the  writing  of  a 
description  or  analysis  of  the  method  employed 
only  helps  to  fix  fundamental  principles  and 
to  clarify  obscure  facts.     In  the  free-trade  of 
science,  as  in  the  charity  of  every-day  life,  it 
is  more  blessed  to  give  than  to  receive. 


Nipissing  and  Camp  Bird. 

We  are  indebted  to  Mr.  Willet  G.  Miller, 
the  Provincial  Geologist  of  Ontario,  for  a  his- 
torical note  concerning  the  incident  that  led  to 
the  first  purchase  of  the  Nipissing  mine  from 
its  original  discoverers.  As  Mr.  Miller  him- 
self says,  the  memories  of  men  are  rendered 
fallible  by  time,  so  that  fantastic  tales  arise 
concerning  the  discovery  of  famous  mines. 
Yet,  in  many  cases,  as  in  this  of  the  Nipissing, 
the  fact  is  fully  as  interesting  as  the  fiction. 
That  a  purchaser  of  rare  minerals  should  have 
seen  an  article  in  a  technical  journal  and  be 
led  thereby  to  investigate  the  value  of  a  new 


discovery,  which  eventually  proved  to  be  a 
great  silver  mine,  is  more  notable  than  that 
a  young   man   hunting  wild  game  should  be 
shown  some  rich  specimens  by  a  prospector 
and    should    forward    these    specimens    to   a 
wealthy  father  in  New  York  who  then  sent  a 
cheque  in  purchase  of  the  mine.     We  have 
only  to  add  that  the  story  as  told  to  us  came 
from  a  mining  engineer  who  obtained  his  in- 
formation direct  from  Mr.   Earle.     This  also 
illustrates  another  curious  human  tendency, 
namely,  that  of  the  discoverer  himself  to  vary 
the  story  of  the  episode  that  led  to  the  acquisi- 
tion of  a  bonanza  until  by  a  sort  of  subcon- 
scious metamorphism   the  facts  are  given  a 
form  apparently  more  attractive.     We  recall 
another  case  :  that  of  Thomas  F.  Walsh,  the 
fortunate  discoverer  of  the  Camp  Bird  mine 
in  Colorado.     Not  long  before  his  useful  and 
honourable  life  came  to  an  end,  Tom  Walsh, 
as  he  was  called  in  the  West,  gave  an  address 
before  the  Colorado  School  of  Mines  and  re- 
counted some  of  his  experiences  with  a  view 
to  emphasizing  the  value  of  technical  science, 
especially  mineralogy.     As  an  illustration  he 
told  how  he  had  discovered  the  Camp  Bird 
mine.     In  1894  he  had  acquired  the  Hidden 
Treasure,    a   low-grade    silver-lead    mine    in 
Imogene  basin,  near  Ouray,  Colorado.     On 
one  of  his  visits  thither  from  Silverton,  where 
he  was  operating  a  small  smelter,  he  noticed 
a  '  slide  '  (or  talus)  "  of  red  pyritiferous  por- 
phyry," because  it  had  "  a  very  strong  indica- 
tion of  gold  in  or  near  it."     Samples  of  this 
rock  assayed  $2  in  gold.     This  "  confirmed 
his   suspicion  "   that  there   were  gold   veins 
somewhere  in    Imogene   basin.     Among  the 
claims  acquired  by  him  in  the  hope  of  obtain- 
ing silicious  ore  for  his  matte-smelter  at  Sil- 
verton, was  one  near  the  porphyry    slide  '  and 
he  suspected  that  the  vein  on  which  this  claim 
was  located  must  pass  "  through  or  near  the 
porphyry  dike  and  that  it  carried  gold."     So 
his  faithful  henchman  Andy  Richardson  was 
told  to  drive  a  tunnel  through  the  snow  lying 


OCTOBER,    1911 


263 


on  the  mountain-side  with  a  view  to  breaking 
some  samples  from  the  abandoned  workings. 
But  that  did  not  suffice,  Walsh  felt  that  he 
must  take  his  own  samples,  so  he  went  him- 
self and  found  a  dump  of  very  showy  ore, 
having  zinc,  lead,  and  some  copper  pyrites." 
The  rest  of  the  story  is  best  told  in  his  own 
words  :  "  1  went  inside  and  examined  the  vein. 
There  1  found  an  18-inch  streak  of  the  same 
kind  of  ore  that  was  on  the  dump.  Between 
it  and  the  hanging  wall  there  was  about  3  feet 
of  modest-looking  quartz As  I  exam- 
ined it  closely  I  saw  little  specks  and  thread- 
like circles  of  glistening  black  mineral  all 
through  it,  which  experience  told  me  was  gold 
in  a  telluride  form."  Samples  of  this  quartz 
assayed  "  as  high  as  $3000  per  ton." 

This,  of  course,  was  what  he  honestly  be- 
lieved on  May  22,  1908,  when  he  was  address- 
ing the  mining  students,  but  it  is  not  the  story 
as  related  by  himself,  in  the  presence  of  Andy 
Richardson,  to  the  present  writer  in  July  1900. 
We  were  standing  in  Imogene  basin  and  look- 
ing at  the  steep  slope  into  which  the  Gertrude 
workings  had  penetrated,  with  the  dump  and 
talus,  of  which  mention  has  already  been  made. 
In  July  1896  he  was  making  a  visit  to  the 
Hidden  Treasure.  Looking  up  toward  the 
steep  slope  leading  to  Red  Mountain  he  noticed 
some  pink  spar  ;  this  reminded  him  of  the 
fluorite  associated  with  gold  ore  at  Cripple 
Creek,  where  he  had  operated  the  Deerhorn 
and  Summit  mines  a  few  years  earlier.  In 
September  he  returned  to  the  locality  and  de- 
cided to  investigate  the  workings  from  which 
this  pink  spar  had  come.  The  rest  of  the 
story  is  as  he  stated,  but  the  pink  spar  was 
rhodonite,  the  silicate  of  manganese,  and  the 
black  threads  of  glistening  mineral  refer  prob- 
ably to  information  obtained  at  a  much  later 
date,  when  it  was  ascertained  by  microscopic 
investigation  that  the  black  threads  in  the 
richest  of  the  Camp  Bird  ore  consisted  of  free 
gold,  galena,  blende,  and  occasional  traces  of 

a  telluride,  the  identity  of  which  was  never 
4—3 


ascertainedSwith  certainty.  In  any  event  it 
was  not  recognizable  by  the  naked  eye  and 
bore  no  likeness  to  the  calaverite  and  sylvanite 
so  common  at  Cripple  Creek,  where  the  dis- 
coverer of  the  Camp  Bird  had  obtained  the 
particular  experience  to  which  he  referred. 

But  this  does  not  exhaust  the  romance  of 
the  Camp  Bird  nor  that  of  the  Gertrude  claim, 
with  its  curiously  prophetic  suggestion  of  the 
Santa  Gertrudis,  which,  in  Mexico,  was  des- 
tined to  redress  the  balance  of  the  exhausted 
wealth  of  the  Camp  Bird,  in  Colorado.  An 
earlier  chapter  remains  to  be  read.  The  Ger- 
trude in  Imogene  basin  was  located  by  William 
Weston  and  George  Barber  in  1877  and  was 
one  of  the  claims  acquired  by  the  Allied  Mines 
Co.,  in  1878.  The  workings  found  by  Walsh 
in  1896  were  made  by  H.  W.  Reed  and  Caleb 
Reed  in  1884.  Mr.  William  Weston  was 
manager  for  the  Allied  Mines,  a  wild-cat  en- 
terprise on  which  Dr.  R.  W.  Raymond  re- 
ported adversely  in  1878.  On  the  dismantled 
window-ledge  of  the  assay-office  of  the  Allied 
Mines  Co.  in  1896  was  found  a  piece  of  ore 
similar  to  that  which  Walsh  proved  to  be  so 
rich  and  which  gave  a  key  to  the  treasure- 
vault  that  made  him  a  multi-millionaire.  Good 
reason  exists  for  believing  that  Mr.  Weston 
assayed  the  ore  for  silver  only  and  that  he 
failed  to  part  the  button.  Silver  mining  was 
then  the  vogue  in  that  part  of  Colorado.  The 
ore  contained  only  a  little  silver,  the  vein  was 
considered  unprofitable,  and  remained  dispar- 
aged until  Walsh  had  his  samples  assayed  at 
Ouray  18  years  later.  Mr.  Weston  still  lives, 
an  honoured  citizen  of  Denver,  and  we  need 
not  dwell  on  the  bitter  irony  of  fate  that  led 
him,  with  his  certificate  in  assaying  from  the 
Royal  School  of  Mines,  to  miss  the  oppor- 
tunity of  a  lifetime.  If  he  had  parted  those 
little  buttons  of  silver  he  would  have  found 
that  they  contained  a  large  proportion  of  gold 
and  he — not  Walsh—  would  have  been  the 
discoverer  of  the  orebody  that  gave  fame  to 
Walsh  and  to  the  Camp  Bird  company. 


264 


THE    MINING    MAGAZINE 


METAL  MARKETS 

COPPER. 

Average  prices  of  cash  standard  copper : 

Sept.  1911.        August  1911.       Sept.  1910. 
£55.  7s.  Id.         ^56.  7s.  6d.        ^55.  6s.  5d. 

The  steadiness  of  prices  in  face  of  demoral- 
ized markets  everywhere  is  truly  remarkable. 
While  copper  and  other  industrial  shares,  un- 
der the  influence  of  political  scares,  dearer 
money,  and  fears  of  trust  prosecutions  in 
America,  have  suffered  severe  depreciation, 
the  metal  itself  has  borne  the  shock  with 
firmness.  This  undoubtedly  points  to  a  small 
bull  interest,  and  at  the  same  time  the  reason- 
able prices  and  the  enormous  consumption 
discourage  bears  from  operating.  The  Euro- 
pean absorption  of  copper  shows  no  sign  of 
saturation,  and  if  the  various  troubles  that 
have  afflicted  markets  in  the  past  few  months 
have  affected  the  issue  of  new  orders,  the 
check  has  been  only  temporary.  Moderate 
prices  ruling  over  a  long  period  have  encour- 
aged enormously  the  present  demand,  and  we 
must  conclude  that  this  process  will  continue 
until  stocks  are  sufficiently  exhausted  to  af- 
fect prices,  when  again  consumption  will  be 
checked.  Meanwhile  fresh  electrification 
schemes  are  being  fostered.  The  increasing 
output  from  the  new  '  porphyry '  mines  in 
America  is  probably  no  more  than  the  ex- 
panding growth  in  demand  will  require.  The 
Amalgamated  interests  are  practically  out  of 
the  market  at  the  prices  they  are  quoting. 
Other  producers  have  shaded  quotations,  but 
insufficiently  to  attract  big  business.  Stocks 
in  consumers'  hands  must  be  small ;  a  sub- 
stantial buying  movement  therefore  is  bound 
to  follow  as  soon  as  the  large  producers  make 
up  their  minds  to  meet  the  market. 

LEAD. 

Average  prices  of  soft  foreign  lead  : 

Sept.  1911.        August  1911.         Sept.  1910. 
/14.  15s.  Id.     ;^14.  Is.  4d.        £\2.  12s.  6d. 

Lead  has  advanced  steadily  and  rapidly, 
and  a  further  rise  of  nearly  20s.  has  been 
made.  At  the  end  of  the  month  some  profit- 
taking  by  speculators  was  in  evidence,  and  a 
little  bear  selling  accompanied  it,  but  when 
consumers  showed  a  disposition  to  take  ad- 
vantage of  the  lowered  prices  sellers  with- 
drew. The  position  is  one  of  undiminished 
strength,  consumption  being  far  in  excess  of 
present  supply  ;  to  add  to  the  difficulty  Spanish 
freights  have  advanced,  as  prompt  steamers 


are  almost  unprocurable.  There  are  no  re- 
serve stocks  anywhere,  and  still  higher  prices 
are  in  sight. 

TIN. 

Average  prices  of  cash  tin  : 

Sept.  1911.       August  1911.       Sept.  1910. 
;^180.  16s.  lid.   ^190.  9s.  7d.     ^160.  8s.  7d. 

Though  the  market  has  not  been  entirely 
free  from  the  violent  see  -  saw  fluctuations 
which  characterize  it,  the  excitement  has  been 
rather  less  than  usual.  The  tendency  on  the 
whole  has  been  downward.  The  attitude  of 
the  syndicate  is  no  longer  evident,  and  dealers 
have  been  operating  with  hesitation.  The 
outside  public  have  ceased  to  take  a  hand  in 
the  game  as  they  are  nervous  of  the  labour 
situation,  and  of  the  syndicate's  influence. 
Prices  over  the  month  show  an  extreme  fluc- 
tuation of  ;^20,cash  tin  having  sold  at  one  time 
as  low  as  iTni.  The  close,  however,  shows 
a  recovery  from  this  low  level  to  ;^179.  10s. 
Although  the  outlook  is  somewhat  obscure,  the 
onlooker  cannot  fail  to  take  an  unfavourable 
view  of  future  market  developments. 

SPELTER. 

Average  prices  of  good  ordinary  spelter  : 

Sept.  1911.        Augustl911.         Sept.  1910 

^"27.  12s.  7d.      ;^26.  lis.  2d.        £?3.  2s.  7d. 

Conditions  have  not  changed  during  the 
month.  The  convention  is  not  in  a  position 
to  sell  freely,  and  therefore  fails  to  let  con- 
sumers have  the  supplies  they  require.  At 
the  same  time  their  interests  are  against  a 
further  rise.  It  remains  to  be  seen  how  they 
will  meet  the  situation.  Outside  interests, 
mainly  American,  are  now  competing  ;  dealers 
have  disposed  of  their  second-hand  parcels, 
and  are  watching  the  market.  In  all  branches 
consumers  are  fully  employed. 

OTHER  METALS  AND  MINERALS. 

Prices  quoted  on  October  7  : 

Silver. — 24jd.  per  oz. 

Platinum. — 178s.  6d.  per  oz. 

Bismuth. — 7s.  6d.  per  lb. 

Aluminium. — ^53  per  ton. 

Nickel.- — ^170  per  ton. 

Cobalt. — 9s.  9d.  per  lb. 

Antimony. — ;^28  per  ton. 

Quicksilver.- — ^"8.  12s.  6d.  per  flask. 

Manganese  Ore. — 8d.to9id.  per  unit  (1%). 

Iron  Ore. — Cumberland  hematite  19s.  6d. 
per  ton  at  mine.    Spanish  19s.  delivered. 

Pig  Iron. — Cleveland  47s.  per  ton.  He- 
matite 62s.  per  ton. 

Wolfram  Ore — 31s.  per  unit  (1%). 


SPECIAL    CORRESPONDENCE 


News   from  our  own  Correspondents  at  the  principal  mining  centres 


TORONTO. 

Porcupine. — The  work  of  reconstruction 
at  Porcupine  has  made  great  progress  during 
the  last  few  weeks,  notwithstanding  the  diffi- 
culty of  getting  building  material.  In  the  town 
of  Porcupine  more  than  400  buildings  have 
been  erected.  Government  roads  are  being 
rapidly  completed,  and  in  many  directions 
heavy  teaming  can  be  undertaken  without 
waiting  for  the  cold  weather.  At  most  of  the 
mines  where  buildings  and  plants  were  de- 
stroyed by  the  fire,  operations  have  been  re- 
sumed. It  is  estimated  that  about  2000  men 
are  engaged  in  mining  in  the  district,  and  1000 
more  employed  m  building  and  road-making. 
The  Porcupine  branch  of  the  Temiskaming  & 
Northern  Ontario  railway  will  be  extended 
across  the  Pearl  Lake  district  through  the 
Hollinger  property  to  the  Campbell  Veteran 
claim,  where  a  new  townsite  has  been  laid  out 
near  the  Mattagami  river.  This  is  known  as 
Timmins,  and  will  be  made  the  headquarters 
of  some  of  the  large  companies  operating  in 
the  neighbourhood.  The  most  important  event 
during  the  last  few  weeks  was  the  discovery  of 
a  rich  vein  on  the  Dome.  In  trenching  on 
the  eastern  part  of  the  property,  about  600  ft. 
from  the  present  workings,  a  vein  20  ft.  wide 
was  encountered  showing  free  gold  in  unusual 
profusion,  in  patches  from  the  size  of  a  pin's 
head  to  half-an-inch  in  diameter.  The  vein  has 
been  stripped  for  72  ft.,  and  apparently  runs 
into  the  Dome  Extension.  The  Dome  com- 
pany has  increased  its  capital  from  $2,500,000 
to  $3,500,000  by  the  issue  of  additional  stock 
to  the  amount  of  $1,000,000,  to  be  taken  up 
by  present  shareholders.  At  the  Hollinger  a 
new  shaft  is  down  20  ft.  and  rises  will  be  made 
from  the  100  and  200  ft.  levels  to  connect  the 
workings.  A  new  compressor  and  hoist  have 
been  installed,  but  the  power  is  not  yet  avail- 
able. Two  veins  carrymg  free  gold  have  been 
found  on  the  north  lot.  One  of  them  is  from  2  to 
9  ft.  wide  and  has  been  traced  for  over  300  ft.  A 
rich  vein  22in.  widecarrying  freegoldand  much 
sulphidehas  been  foundon  the  North  Dome.  At 
the  Pearl  Lake  a  good  strike  has  been  made  at 
90  ft.  in  the  '  A  '  shaft.  The  '  B  '  shaft  is  down 
to  the  100-ft.  level,  where  a  drift  40  ft.  long 
exposes  an  orebody  12  ft.  wide.  A  12-drill 
compressor  and  2  stamps  are  being  erected. 
The  West  Dome  has  installed  three  boilers  of 


150  hp.  capacity,  and  a  hoist  and  a  power-plant 
are  nearly  completed.  The  company  has  bought 
the  half-interest  of  Elijah  Woodward  and  H. 
M.  Pell  in  the  two  Kcrtz  claims  adjoining  its 


Northern  Ontario. 

property.  A  vein  with  a  good  showing  of  free 
gold  5  ft.  wide  has  been  found  in  the  northwest 
corner  of  the  Imperial  property.  Two  shafts 
are  down  on  the  Rea  for  200  ft.  Shaft  No.  1 
will  be  sunk  another   100  ft.,   making   it  the 


265 


266 


THE    MINING    MAGAZINE 


deepest  working  in  the  district.    About  300  ft. 
of  driving  has  been  done  at  the  200  ft.  level 
where  the  vein  is  4  ft.  wide  and  free  gold  has 
been  found  in  several  places.     A  large  quartz 
vein  60  ft.  wide  has  been  uncovered  for  over 
250  ft.  and  found  to  be  a  continuation  of  the 
main  vein.  At  the  Jupiter  two  shafts  are  being 
sunk  ;  one  of  them  is  down  to  the  100  ft.  level, 
and  cross-cutting  has  begun.     A  compressor 
has  been  ordered.     The  Plenaurum  is  sinking 
two  shafts,  one  north  and  the  other  south  of 
Pearl  Lake.  An  11 -drill  compressor,  a  200  hp. 
motor  and  an  auxiliary  steam -plant  have  been 
ordered.  At  the  Foley-O'Brien  a  new  mineral- 
ized zone  75  ft.  wide  has  been  found  on  the 
southern  part  of  the  property.     A  shaft  will  be 
sunk  and  exploration  undertaken  by  steam- 
drills.     A  vein  35  ft.  wide  has  been  discovered 
on  the  Porcupine  Reserve  property  known  as 
the  Birke  claim,  and  stripped  for  500  ft.,  giv- 
ing good  pannings.     The  American  Goldfields 
has  resumed  operations  and  is  sinking  on  two 
veins,  from  which  ore  is  being  extracted.  The 
Eldorado  has  struck  a  vein  rich  in  free  gold. 
The  Three  Nations  Co.,    whose   claims  are 
about  three  miles  east  of  Golden  City,   has 
ordered  a  7-drill  compressor   and  boilers  of 
200  hp.  capacity.  The  Reciprocity  Mines  Ltd. 
has  beenorganizedwithacapital  of  $1,000,000, 
and  has  taken  over  the  McKenzie  Veteran 
claim  of  160  acres  some  distance  north  of  the 
Rea  mines.    A  syndicate  of  Duluth  capitalists 
has  bought  the  two  Sutherlandclaims  in  Bristol 
township  for  a  sum  stated  at  $300,000.    The 
Waters-Harris  syndicate  of  New  York  has 
purchased  280  acres  southwest  of  the  HoUin- 
ger.     Numerous  discoveries  of  ore  carrying 
free  gold  are  reported  from  Thomas,  Cody,  and 
Timmins  townships. 

A  new  goldfield  at  West  Shining  Tree, 
40  miles  north  of  Gowganda  Junction  and 
accessible  either  from  that  point  by  canoe,  or 
by  train  and  canoe  from  Sudbury,  is  attracting 
large  numbers  of  prospectors.  The  pioneer, 
Alfred  Gosselin,  has  a  claim  on  which  a  10  ft. 
quartz  vein  has  been  uncovered  ;  rich  samples 
have  been  taken  from  this,  showing  free  gold 
throughout.  Churchill,  McMurchy,  Asquith, 
and  Fawcett  townships  are  being  rapidly 
staked  and  the  daily  arrivals  number  150. 

Metal  Production  of  Ontario. — An  offi- 
cial statement  issued  by  the  Ontario  Bureau 
of  Mines  gives  the  output  of  silver  for  the  six 
months  ending  June  30  at  15,231,969  oz.  of 
the  value  of  $7,644,200,  being  an  increase  of 
2,417,142  oz.  and  $1,376,670  as  compared 
with  the  first  six  months  of  1910.  Of  the 
total,  430,540  oz.  came  from  Gowganda  and 


South  Lorrain.  Thetonnage  of  ore  and  concen- 
trate shipped  from  Cobalt  was  12,001  tons,  as 
against  14,868  during  the  corresponding  period 
last  year.     The  bullion  shipments  amounted 
to  1,302,699  oz.     There  is  a  growing  tendency 
on  the  part  of  the  mining  companies  to  confine 
their  ore  shipments  largely  to  high  grade  and 
treat  the  lower  grade  ore  at  the  mills.     One 
result  of  this  change  is  the  appearance  in  the 
official  returns  for  the  first  time  of  the  by-pro- 
ducts of  the  separation  and  refining  processes, 
namely,   cobalt  and  nickel   oxides,  of  which 
219,5841b.  was  produced,  valued  at  $64,876. 
The  yield  of  gold  remams  small,  being  only 
2276  oz.  valued  at  $42,320.     The  output  of 
pig  iron  was  255,303  tons,  worth  $3,923,593. 
Cobalt. — The  difference  between  the  poli- 
cies pursued  by  the  La  Rose  and  Nipissing 
companies    in   the  matter   of   dividends,   the 
former  accumulating  a  large  cash  surplus  by 
keeping  the  dividends  small,  while  the  other 
pays  heavy   dividends  and  depends   for  the 
future  on  its  ability  to  maintain  the  present 
rate  of  shipments,  has  been  emphasized  by  the 
withdrawal  of  D.  Lome  McGibbon,  president 
of  La  Rose,  from  the  directorate  of  the  Ni- 
pissing.    It  is  understood  that  a  difference  of 
opinion  on  the  dividend  policy  was  the  cause 
of  his  action.     The  merger  of  the  two  com- 
panies, which  was  at  one  time  regarded  as 
highly  probable  on  account  of  the  identity  of 
the   interests  of  the  respective   directorates, 
now  appears  out  of  the  question.     President 
McGibbon's  stand,  moreover,  is  taken  as  indi- 
cating that  the  agitation  for  an  increase  in  the 
dividend  rate  of  La   Rose  is  unlikely  to  be 
successful.    The  Nipissing  is  now  treating  and 
refining  nearly  all  of  its  high-grade  ore  at  its 
own  plant  and  recovering  practically  all  of  the 
silver.     When  an  outstanding  contract  for  the 
treatment  of  ore  expires,  it  will  refine  all  its 
high- grade,  and  experiments  are  being  made 
to  ascertain  whether  second-class  ore  can  also 
be  profitably  treated.     The  saving  resulting 
from  the  treatment  of  the  first-class  ore  is  esti- 
mated at  $300,000  annually.     The  new  con- 
centrator at  Cobalt  Lake  mine  is  ready  for 
operation.     It  will  have  a  capacity  of  75  tons 
per  day  at  the  start,  and  later  this  will  be  in- 
creased to  100  tons.     The  Crown  Reserve  has 
declared  a  regular  quarterly  dividend  of  2%  and 
a  monthly  bonus  of  3%.     When  this  is  paid 
the  company  will  have  returned  to  its  stock- 
holders $3,449,181,  or  over  twice  its  capitali- 
zation.    No.  14  vein  has  been  picked  up  at  the 
150  ft.  level  where  it  is  3  in.  wide  and  runs 
5000  oz.  to  the  ton.     The  Temiskaming  has 
made  a  good  strike  at  the  575  ft.  level. 


OCTOBER,    1911 


267 


JOHANNESBURG. 
Western  Rand  Estates. — In  the  Rand 
a  circular  shaft  is  a  novelty,  and  as  such  the 
shaft  now  being  sunk  on  this  property  is  in- ' 
teresting.  The  position  of  the  shaft  seems 
to  have  been  chosen  with  the  idea  of  making 
the  work  from  an  engineering  point  of  view 
still  more  interesting  and  instructing  ;  inter- 
esting, as  it  is  necessary  to  sink  through  soft 
mud  until  the  dolomite  is  reached,  the  whole 
containing  large  volumes  of  water ;  and  in- 
structive, more  especially  to  the  company,  as 
the  cost  will  be  considerable.  The  diameter 
of  the  shaft  is  about  18  ft.  inside  the  tubbing, 
which  is  suspended  from  the  surface,  each 
ring  being  bolted  into  the  last  as  the  mud  and 
rock   is  excavated.       The   lining  is  liable  to 


already    carried  out,   it  is  found  that  about 
better  duty  is  obtained  from  the  Nissen 


30 


stamps  than  from  the  stamps  as  run  in  sets 
of  5  in  one  mortar-box.  This  may  mean 
either  that  the  Nissen  stamp  is  doing  good 
work  or  that  the  rest  of  the  stamps  are  doing 
bad  work  :  possibly  a  combination  of  both 
reasons  is  nearest  the  mark. 

The  Prevention  of  Dust  in  development 
drifts  of  mines  during  drilling  operations  was 
the  subject  of  a  paper  read  by  C.  D.  N. 
Jourdan,  of  the  Government  Mines  Depart- 
ment, before  a  meeting  of  the  South  African 
Institute  of  Engineers  held  on  September  9. 
The  method  of  preventing  the  production  of 
dust  is  to  inject  water  alongside  the  drill-bit, 
while    the    machine    is    running.     From   the 


aiRCULAB    SHAFT    OW    THE    WESTERN    RAND    ESTATES. 


swing  out  of  plumb  in  case  of  a  mud  rush  and 
until  a  solid  foundation  is  encountered.  The 
accompanying  photographs  show  the  nature 
of  the  work. 

The  Nissen  Stamp. — Experiments  are 
being  conducted  at  the  City  Deep  on  the 
Nissen  stamp.  As  is  well  known,  the  Nissen 
consists  of  a  single  stamp  working  in  its  own 
mortar-box,  the  idea  being  that  at  every  drop 
of  the  stamp  a  maximum  of  useful  effect  is 
obtained,  which  may  not  always  be  the  case 
where  several  stamp-heads  are  running  to- 
gether in  the  same  mortar-box,  due  to  the 
wave  motion  of  the  pulp  across  the  dies. 
Another  point  in  favour  of  the  Nissen  stamp 
would  seem  to  be  that  the  dies  wear  more 
uniformly  under  such  conditions  as  obtain 
when  each  stamp  has  its  own  mortar-box, 
than  they  do  in  the  case  of  the  usual  5  stamps 
in  one  mortar-box,  where  the  dies  are  found 
to    wear   most   irregularly.     From    the   tests 


tests  at  the  Nourse  mine,  Mr.  Jourdan  ob- 
tained the  following  figures  proving  the  sav- 
ing effected,  both  in  time  and  steel,  by  the 
use  of  water.  In  one  case  it  took  93  minutes 
to  drill  a  dry  hole  31  inches,  as  against  59 
inches  drilled  in  422  minutes  when  water  was 
used,  both  holes  having  been  drilled  in  ground 
of  exactly  the  same  nature.  In  another  case 
48  inches  was  drilled  in  150  minutes,  dry 
hole,  as  against  68  inches  in  87  minutes  when 
using  water.  In  all  cases  these  figures  are 
the  results  of  drilling  with  the  usual  machine 
with  cylinder  3i  in.  diameter.  It  is  also 
estimated,  apart  from  the  obvious  saving  in 
time,  that  there  is  a  saving  of  from  30  to  50% 
in  the  drill-bits.  Mr.  Jourdan  states  that  "  the 
universal  adoption  of  this  system  seems  likely 
to  do  away  finally  with  one  of  the  chief  causes 
of  the  formation  of  dust  in  developing  drives." 
It  will  do  much  more.  With  the  large  num- 
ber of  hammer-drills  in  use  on  the  Rand  at 


268 


THE    MINING    MAGAZINE 


the  present  time,  this  system,  if  adopted, 
will  increase  greatly  the  underground  effi- 
ciency for  rising  and  back-stoping  generally, 
and  any  increase  in  costs  occasioned  by  ex- 
tra pipe-laying  and  pumping  will  be  amply 
repaid    by    the    saving   effected  in   breaking 

ground. 

Coal  Contracts.— It  is  interesting,  in  view 
of  the  fact  that  The  Times  engineering  supple- 
ment of  August  2  contained  a  leading  article 
on  '  The  Purchase  of  Fuel,'  to  record  the  basis 
on  which  the  large  mining  groups  purchase 
their  coal.  It  is  bought  through  the  medium 
of  the  Transvaal  Coal  Owners  Association, 
and  each  purchasing  company  can  select  any 
colliery  or  collieries  under  the  control  of  the 
Association.  The  quality  of  the  coal  supplied 
is  fixed  at  a  given  calorific  standard  for  each 
colliery.  The  calorific  values  are  ascertained 
by  the  Mahler  bomb  calorimeter,  and  are  cal- 
culated upon  the  coal  as  delivered  to  the  con- 
sumer and  not  upon  dry  coal.  The  classes  of 
coal  are : 

(a)  Round  Coal  (+  1  m.  mesh). 

(&)  Nut  Coal  (-  1  in.  and  +  fin.  mesh). 

(c)  Pea  Coal  ( -  f  in.  and  +  re  in.  mesh.) 

id)  Duff  or  fine  (-  t6  in.  mesh). 
Fine  must  not  exceed  7i%  in  the  case  of  round 
coal,  10%  for  nut,  and  124%  for  pea,  the  per- 
centages being  calculated  by  weight.  The 
classes  of  coal  with  their  average  calorific 
values  guaranteed  as  per  Mahler  bomb  tests 
are  as  follows : 


Average  Calories. 

Class  of  Coal. 

Round. 

Nut. 

Witbank  

12'5 

12*2 
107 

ir9 

West  Witbank 

Snrinefs 

11*6 
10"2 

The  calorific  value  referred  to  is  the  larger 
calorie,  that  is,  the  pounds  of  water  evaporated 
per  pound  of  coal  from  and  at  212°  F.  The 
price  of  coal  at  the  pithead  is  about  5s.  per  ton 
for  round  and  4s.  per  ton  for  nut ;  in  addition, 
about  8s.  per  ton  is  added  for  freight  charges. 
The  ton  is  the  short  ton  of  2000  lb.  Thus 
roughly  the  prices  for  coal,  when  delivered  at 
the  mines,  are  13s.  per  ton  for  round  and  12s. 
per  ton  for  nut.  Assuming  that  any  mine  is 
buying  coal  with  a  guaranteed  calorific  value 
of  12  C.  at  13s.  per  ton  and  on  analysis  the 
calorific  value  is  found  to  be  only  \\'5  C,  then 
the  price  paid  for  the  coal  would  be  12s.  5id. 
It  is  interesting  to  note  that  the  proportion  is 


worked  out  over  the  total  cost  per  ton,  that  is, 
the  pithead-price  plus  freight-charge,  and  not 
on  the  pithead-price  alone,  a  point  which 
makes  it  to  be  to  the  benefit  of  the  colliery  to 
supply  the  best  coal. 

An  increase  in  calorific  value  might  or 
might  not  alter  its  density.  As  an  example,  if 
a  poor  truck-load  containing  dense  hard  shale 
were  compared  with  a  truck-load  of  clean  coal, 
the  density  of  the  material  in  the  former  would 
be  greater  than  that  in  the  latter,  but  the 
calorific  value  of  the  latter  would  be  greater 
than  that  of  the  former  ;  one  disadvantage  of 
buying  by  weight  alone  can  thus  easily  be  seen. 
By  this  system  of  purchasing  coal,  the  pur- 
chaser, knowing  that  his  coal  will  be  of  con- 
stant quality,  gains  the  advantage  of  being  able 
to  adjust  his  steam-plant  to  suit  the  fuel,  and 
hence  obtains  a  maximum  efficiency. 

The  East  Rand  Proprietary  Mines. — 
The  recent  disclosures  are,  to  say  the  least, 
astonishing.  The  position  of  affairs  for  some 
time  past  has  been  that  the  group  has  tried  to 
maintain  a  profit  beyond  that  possible  with 
their  grade  of  ore  and  working  costs,  in  order 
that  a  40%  dividend  should  be  declared.  This 
has  necessitated  running  one  month's  output 
into  that  of  the  next  month  and  so  on  ;  for 
example,  if  55,000  oz.  was  required  for  the 
month's  output,  and  if  at  the  end  of  the  month 
there  was  still  a  deficit  of  5000  oz.,  this  would 
be  obtained  from  the  first  few  days  run  of  the 
succeeding  month.  Unless  therefore  there 
was  an  appreciable  rise  in  the  grade  of  ore 
milled,  a  time  was  bound  to  come  when  the 
forcing  policy  must  end.  This  has  now  hap- 
pened, and  the  official  statement  to  account 
for  the  fall  in  profit  is  to  the  effect  that  owing 
to  extraction  difficulties  there  has  been  lost  in 
the  cyanide  works  no  less  than  13,000  oz.  of 
gold  or  about  ;^54,600  of  revenue.  On  the 
other  hand,  everything  in  the  reduction  works 
has  been  watched  so  carefully  to  get  every 
possible  ounce  out  of  the  ore  that  amalga- 
mating plates  have  been  steamed  and  scraped 
several  times  in  a  month,  and  zinc  shaving, 
etc.,  wasted  by  cleaning  up  too  closely  in  the 
cyanide  works.  As  to  the  mine,  the  Cason 
portion  contains  the  lowest-grade  ore,  and  at 
present  the  development  in  this  section  seems 
to  be  in  a  particularly  poor  zone.  W^ith  a  mine 
of  this  size,  however,  having  an  enormous  ton- 
nage of  ore  developed,  it  should  not  be  difficult 
to  keep  the  value  of  the  ore  milled  at  a  fairly 
constant  figure.  For  the  way  in  which  matters 
have  drifted  on  the  East  Rand  Proprietary 
Mines,  the  management  deserves  strict  cen- 
sure, as  cases  of  this  kind  are  calculated  to 


OCTOBER,    1911 


269 


cause  much  harm  to  the  mining  industry  of 
this  country  by  shaking  confidence  in  it  gener- 
ally. 

The  Giesecke  Mill. — In  your  issue  for 
August  reference  is  made  in  your  editorial 
columns  to  this  mill,  which  the  Mines  Trials 
Committee  has  since  apparently  definitely  re- 
jected on  its  guarantees.  Among  those  com- 
petent to  judge,  the  Giesecke  mill  was  never 
expected  to  do  all  that  was  claimed  for  it. 
Viewed  as  a  glorified  tube-mill,  there  was  no 
real  reason  to  suppose  that  it  would  do  more 
than  the  ordinary  tube-mill  would  do,  under 
similar  conditions.  Many  inventionshave  been 
tried  on  the  Rand  that  were  to  have  superseded 
the  Californian  stamp-mill,  but  none  have  been 


SALT  LAKE  CITY. 
A  distressing  incident  was  the  fire  in  the 
Giroux  shaft  of  the  Giroux  Consolidated  at 
Ely,  Nevada,  on  August  25.  The  Giroux  is 
a  new  5-compartment  shaft  that  is  being  sunk 
and  has  reached  1440  ft.  Ten  men  were  at 
work  in  the  bottom  when  they  discovered  the 
shaft  on  fire  at  the  1200-ft.  level.  It  is  be- 
lieved that  a  barrel  of  oil  in  the  pump-station 
became  ignited  and  exploded,  scattering  its 
burning  contents,  but  the  exact  cause  will 
probably  never  be  certainly  known  as  the  only 
man  who  could  give  the  information  is  dead. 
The  men  ascended  to  just  below  the  fire  and 
the  party  divided,  five  deciding  to  attempt  to 
pass  through  the  fire  in  the  cage  and  five  walk- 


GIROUX  SHAFT.    STEEL   TOWERS   TO  SUPPORT  HOISTING  ROPE. 


successful.  This  does  not  prove,  however,  that 
a  mill  of  one  type  or  another  will  not  yet  be  in- 
vented, and  do  better  than  the  gravity  stamp. 
In  the  meanwhile,  every  method  of  crushing 
should  be  given  a  fair  trial  under  actual  work- 
ing conditions,  on  a  large  scale,  and  until  such 
trial  has  proved  the  success  or  otherwise  of  the 
innovation,  it  is  bad  policy  to  make  statements 
that  may  ultimately  be  proved  to  be  wide  of 
the  mark.  [According  to  later  advices  the 
Nissen  stamp  has  been  adopted  at  the  City 
Deep  on  trials  showing  an  efficiency  30% 
higher  than  that  of  the  stamp.  We  await 
details  with  interest,  for  this  departure  may 
prove  far-reaching. — Editor.] 


ing  through  the  level  to  the  Alpha  shaft,  fa 
downcast- shaft  750  ft.  farther  north.  One  of 
the  men  on  the  cage  was  dead  on  reaching  the 
surface,  one  died  later  in  the  hospital,  and  the 
five  men  in  the  Alpha  workings  were  all  over- 
come by  smoke  and  gases  before  reaching  the 
surface,  as  some  excited  workman  turned  on 
the  shaft-sprinkling  device  without  waiting  for 
orders,  thus  driving  the  gases  of  combustion 
through  the  Alpha  shaft.  The  accident  is  even 
more  regrettable  in  that  apparently  every  pre- 
caution had  been  taken  to  prevent  the  occur- 
rence of  such  a  disaster.  The  fire  itself  was 
not  a  serious  matter  though  the  shaft  had  to 
be  closed  and  sealed  before  it  was  brought 


270 


THE    MINING    MAGAZINE 


under  control.  The  manner  in  which  the  share- 
market  exaggerates  the  effect  of  changes  for 
better  or  worse  in  mines  is  well  illustrated  by 
this  case.     The  maximum  amount  of  damage 
that  could  accrue  from  the  fire  would  not  ex- 
ceed $100,000,  yet  the  shrinkage  in  value  of 
the  property  represented  by  the  decline  m  quo- 
tations amounted  to  something  like  $  1 ,500,000. 
The  Giroux  Consolidated,  it  will  be  remem- 
bered, owns  the  ground   lying  between  the 
Liberty  pit  of  the  Nevada  Consolidated  and 
the  Veteran  mine  (formerly  held  by  the  Cum- 
berland-Ely, but  now  a  part  of  the  Nevada 
Consolidated),  which  includes  prophyry  ore- 
bodies  not  yet  fully  developed,  but  known  to 
contam  some  10,000,000  tons  of  ore  contain- 
ing  between    Tl    and    r5%  copper.      In  the 
Alpha  workings   replacement   bodies    in    the 
limestone  occur,  showing  rich  copper  ore.    At 
the  1200-ft.  level  the  ore  is  oxidized,  and  at 
1440  ft.  the  Giroux  shaft  is  still  in  the  zone 
of  oxidation,  but  it  is  expected  soon  to  reach 
the  zone  of  enrichment,  when  it  is  hoped  that 
large  masses  of  rich  sulphides  will  be  found. 
A  contract  has  been    made  with   the   Inter- 
national smelter   at   Tooele,   some   30    miles 
southwest  of  Salt  Lake  City,  for  smelting  the 
ores  from  this  mine.     F.  P.  Mills  is  the  man- 
ager in  Nevada. 

The  Ely  Central,  which  will  long  be  re- 
membered because  of  the  fiasco  in  which  the 
notorious  George  Graham  Rice  was  a  central 
figure,  and  which  has  for  some  time  been  in 
the  hands  of  a  receiver,  is  now  possessed  by 
the  shareholders,  the  receivership  having  been 
recently  dismissed  by  the  Nevada  courts.  It 
is  reported  that  development  will  at  once  be- 
gin, but  as  the  ground  owned  by  the  company 
largely  consists  of  a  flow  of  rhyolite,  lying 
between  the  Ruth  and  Copper  Flat  pits  of  the 
Nevada  Consolidated,  it  is  possible  that  its 
chief  value  will  be  as  a  dumping  ground  for 
the  overburden  from  the  steam-shovel  excava- 
tions. The  Smokey  Development  Co.  which 
now  owns  the  Turner-Ely  ground  has  begun 
churn-drilling,  and  as  this  company  owns  the 
easternmost  of  the  six  areas  of  monzonite- 
porphyry  known  to  exist  at  Ely,  it  is  not  im- 
possible that  good  ore  may  be  developed.  As 
matters  stand  now  the  Nevada  Consolidated 
owns  all  the  best  of  the  porphyry  ore,  and  the 
replacement  bodies  in  limestone  so  far  un- 
covered have  not  proved  of  sufficient  size  to 
be  a  source  of  much  profit. 

The  Nevada  Consolidated  continues  to 
pay  quarterly  dividends  of  372  c.  per  share. 
In  the  recent  second  quarterly  report  a  deficit 
of  $1130  was  announced  after  paying  divi- 


dends amounting  to  $750,000  and  writing  off 
.$137,000  for  depreciation.     The   production 
during  the  quarter  was  somewhat  less  than  the 
average  rate  for  last  year  and  during  July  was 
1,500,000  lb.  less  than  during  the  same  month 
last  year.     This  resulted  from  the  treatment 
of  a  large  amount  of  material  averaging  0'85% 
copper,  representing  a  low-grade  area  found 
in  the  steam- shovel  excavation.  As  this  would 
require  removal  in  any  case,  and  as  it  had  been 
already  stripped  and  could  therefore  be  con- 
sidered free  of  stripping  and  mining  charges, 
this  low  grade  ore  was  sent  to  the  mill.     The 
event  proved  that  it  could  be  treated  at  a  small 
profit.      During  the  summer  it  is  necessary  to 
operate  the  mill  at  a  decreased  capacity,  as  an 
ample  supply  of  water  throughout  the  summer 
in  the  arid  climate  of  Nevada  is  difficult  to 
obtain.      The  smelter  is  using  oil  now   only 
as  a  fuel  in  its  reverberatory   furnaces,  and 
recently  the  high  record  of  over  600  tons  of 
charge  smelted  per  day  was  made  in  one  of 
these  furnaces.   But  as  the  total  given  included 
a  considerable  quantity  of  hot  converter-slag 
and  cold  '  seconds,'   the  record  is  not  so  re- 
markable as  would  at  first  appear,  being  less 
than  500  tons  per  day  according  to  the  more 
usual  method  of  reckoning  tonnage.  A  Pierce- 
Smith  basic  converter  is  about  to  be  blown  in  ; 
the  matte  is  at  present  handled  in  thiee  ordi- 
nary converters  provided  with  basic  linings. 

The  Utah  Copper  Co.  with  mines  at 
Bingham,  some  25  miles  southwest  of  Salt 
Lake  City,  and  mills  at  Garfield  on  the 
southern  edge  of  Great  Salt  lake,  has  been 
steadily  increasing  its  rate  of  production  and 
is  planning  to  operate  at  the  rate  of  20,000 
tons  per  day  ;  over  15,000  tons  is  now  being 
handled.  The  mill  recovery  has  steadily  been 
improved  and  now  reaches  over  75%  in  the 
Arthur  plant  (the  old  Boston  Consolidated 
mill)  which  is  being  remodelled  in  accordance 
with  the  best  results  of  the  experimental  work 
at  the  Magna  plant.  The  Bingham  &  Gar- 
field railroad  is  practically  completed,  but  it  is 
probable  that  its  employment  is  delayed  pend- 
ing a  settlement  with  the  Rio  Grande  Western, 
which  claims  to  have  a  20-year  contract  for 
the  transport  of  ore  at  the  rate  of  12,500  tons 
per  day.  At  the  company's  mine  at  Bingham 
18  to  19  steam-shovels  are  at  work,  most  of 
them  being  employed  in  stripping  the  orebody. 
Ore  and  overburden  are  being  handled  at  the 
rate  of  50,000  tons  per  day.  The  stripping  is 
not  yet  far  enough  advanced  to  allow  the  full 
supply  of  ore  to  be  drawn  from  the  steam- 
shovel  pit,  and  some  3500  tons  are  mined  daily 
underground  by  shrinkage  sloping.     Only  the 


OCTOBER,    1911 


271 


excess  ore  is  drawn  from  the  stopes  and  they 
are  allowed  to  remain  full,  so  that  when  the 
ground  is  afterward  mined  by  steam-shovel 
the  stopes  will  not  be  a  source  of  danger.  The 
ore  thus  broken  and  left  in  the  stopes  can  be 
handled  later  by  steam-shovels  without  any 
subsequent  charge  for  drilling  and  blasting,  so 
that  part  of  the  cost  of  the  present  under- 
ground mining,  which  amounts  to  four  times 
the  cost  of  steam-shovel  mining,  may  properly 
be  regarded  as  a  deferred  charge  to  steam- 
shovel  mining.  Within  six  months  it  is  ex- 
pected that  stripping  will  be  far  enough  ad- 
vanced so  that  underground  mining  can  be 
discontinued.  Churn-drilling  continues  to  ex- 
tend the  amount  of  profitable  ore  developed. 
The  greatest  difficulty  in  drilling  is  experi- 
enced in  the  best  ore,  which  is  naturally  full 
of  '  slips.'  For  this  reason  it  has  proven  im- 
possible as  yet  to  reach  the  lower  limit  of 
some  of  the  best  portions  of  the  ore  deposits 
and  frequent  reports  that  the  ore  reserve  has 
been  increased  by  several  million  tons  do  not 
indicate  that  the  previous  work  was  faulty, 
but  merely  shows,  in  most  cases,  that  a  drill- 
hole has  penetrated  to  a  greater  depth  than 
previous  efforts  had  attained.  The  Utah  Cop- 
per Co.  now  has  25  years'  supply  of  ore,  at  its 
present  rate  of  working,  fully  developed.  This 
averages  1  "67%  copper  and  as  1%  copper  repre- 
sents the  present  limit  of  profitable  treatment, 
it  is  not  at  all  improbable  that  in  the  later  life 
of  the  mine,  when  the  equipment  has  been 
fully  amortized,  large  amounts  of  material  not 
now  regarded  as  ore  will  be  treated  at  a  pro- 
fit. At  present  large  sums  of  money  for  new 
construction  are  being  provided  out  of  the 
operating  charges  and  no  regular  provision 
for  amortization  has  yet  been  made. 

The  Ohio  Copper  Co.  with  mines  that 
immediately  adjoin  the  Utah  Copper  Co.  upon 
the  east,  has  a  small  area  of  monzonite  in  its 
ground,  but  its  main  orebody  consists  of  a  sort 
of  stockwork  in  quartzite.  This  is  now  being 
mined  by  a  caving  system,  called  '  scramming' 
in  the  Lake  Superior  district,  at  a  very  low 
cost.  The  ore  is  milled  through  rises  to  the 
Mascot  adit,  where  the  company  owning  the 
adit  transports  it  at  a  cost  of  15  c.  per  ton  to 
the  Ohio  company's  mill  at  Lark.  This  now 
has  a  capacity  of  1600  tons  per  day,  but  a 
recent  agreement  with  E.  A.  Wall,  noted  for 
his  vendetta  against  the  officers  of  the  Utah 
Copper  Co.,  provides,  according  to  Press  re- 
ports, for  the  enlargement  of  the  mill  to  3000 
tons  per  day  capacity.  It  will  be  remembered 
that  the  versatile  colonel  wished  to  inject  his 
ideas  into  the  milling   practice   of  the   Utah 


Copper  Co.  and  the  results  obtained  in  the 
Ohio  mill  will  be  interesting.  The  ore  of  the 
Ohio  averages  about  r3%  copper,  and  general 
opinion  is  to  the  effect  that  it  might  operate  at 
a  good  profit  if  the  work  were  conducted  on  a 
sufficiently  large  scale.  But  the  company  has 
always  been  straitened  for  funds  to  provide 
for  enlargement. 

The  Utah  Consolidated  is  now  shipping 
its  ore  to  the  Tooele  plant  by  an  aerial  tram- 
way. An  adit  is  also  being  driven  through  the 
range  and  it  is  expected  that  this  will  do  use- 
ful exploratory  work  as  well  as  provide  a  con- 
venient outlet  for  the  ore.  The  Tooele  smel- 
ter, which  is  owned  by  the  International  Smel- 
ting &  Refining  Co.,  was  in  part  constructed 
from  the  material  of  the  former  Utah  Con- 
solidated smelting  plant  at  Bingham  Junction. 
The  plant  has  been  in  successful  operation  for 
about  one  year  and  has  proved  unusually  free 


W     Y      0      M       I       N      G 


-f -T-Z U 

Map  of  Utah. 

from  the  usual  faults  of  design,  but  has  been 
hampered  in  its  operations  by  a  shortage  of 
ore,  as  the  mines  have  been  unable  to  supply 
the  expected  tonnage.  Recently  it  has  been 
decided  to  construct  two  lead  stacks,  which 
together  with  a  baghouse,  are  now  in  process 
of  building.  The  injection  of  a  third  factor  in 
the  lead  smelting  field,  in  which  the  A.  S.  & 
R.  Co.  smelter  at  Murray  and  the  U.  S.  S.  R. 
&  M.  Co.  plant  at  Midvale  are  already  promi- 
nent, is  a  source  of  great  interest  to  producers 
of  lead  ore,  in  the  Idaho  as  well  as  in  the  Utah 
districts,  and  new  contracts  are  being  nego- 
tiated at  favourable  rates. 


272 


THE    MINING    MAGAZINE 


MEXICO. 

Esperanza. — Engineers  representing  this 
company  have  been  examining  the  Escuadra 
mines  in  the  Taviche  district  of  the  State  of 
Oaxaca,  and  it  is  reported  that  the  purchase 
of  the  mines  is  probable.  With  a  view  to 
making  sure  of  future  mining  returns,  the  men 
in  control  of  the  famous  El  Oro  property  some 
time  ago  decided  to  look  for  other  mines,  and 
in  1910a  number  of  properties  were  examined 
but  none  purchased.  The  Escuadra  mines 
produced  heavily  in  colonial  days,  and  have 
been  big  producers  in  recent  years.  They  are 
owned  by  the  heirs  of  Juan  Baigts,  the  Mexi- 
can who  was  engaged  in  litigation  with  Ameri- 
can interests  over  the  ownership  of  the  rich 
San  Juan  mine  in  the  Taviche  district.  This 
litigation  grew  out  of  the  failure  of  the  Ameri- 
cans, several  years  ago,  to  complete  a  deal 
for  the  purchase  of  the  Escuadra  mines  for 
450,000  pesos,  the  San  Juan  contract  contain- 
ing a  proviso  for  the  completion  of  the  Es- 
cuadra negotiations.  After  the  successful  de- 
velopment of  the  San  Juan  mines  by  the 
Americans,  Baigts  recovered  possession  under 
this  proviso,  but  the  Supreme  Court  of  Mexico 
finally  returned  the  mines  to  the  American  in- 
terests. The  price  now  asked  for  the  Escuadra 
mines  has  not  been  made  public. 

Cinco  Minas.  —  The  Cinco  Minas  Co., 
controlled  by  the  Marcus  Daly  interests  of 
New  York,  is  resuming  work  at  these  Jalisco 
mines.  Work  was  stopped  early  this  year 
pending  an  examination  under  an  option 
granted  to  English  interests.  This  examina- 
tion was  suspended  shortly  after  it  was  com- 
menced, owing  to  the  serious  situation  of  the 
country  at  that  time,  and  the  option  expired 
without  any  further  attempt  to  complete  the 
work.  The  Daly  interests  intend  to  build  a 
reduction  plant,  with  a  capacity  of  at  least 
200  tons  daily,  during  the  coming  year.  The 
mines  were  purchased  about  two  years  ago 
for  approximately  500,000  pesos. 

Pearsons. — Francisco  I.  Madero,  leader 
of  the  Madero  revolution  and  unquestionably 
the  next  president  of  Mexico,  announced  re- 
cently that  Lord  Cowdray,  head  of  the  Pear- 
son interests  in  Mexico,  had  visited  him  with 
the  object  of  ascertaining  his  intentions  in  re- 
gard to  the  Pearson  concessions.  He  stated 
that  he  assured  Lord  Cowdray  that  if  the 
Pearson  interests  had  complied  legally  with 
the  provisions  of  the  concessions  granted  to 
them  by  the  Diaz  government,  they  would 
have  nothing  to  fear  from  his  government,  as 
he  expected  to  respect  all  contracts  and  con- 
cessions executed  in  legal  form  by  the  former 


government.  He  stated,  also,  that  he  told 
Lord  Cowdray  he  looked  on  the  action  of  the 
Pearsons  in  fighting  the  Waters-Pierce  Oil 
Co.  in  the  Republic  as  a  great  benefit  to 
Mexico,  as  he  was  absolutely  opposed  to 
monopolies. 

Oil. — It  is  estimated  that  the  present  wells 
in  what  is  known  as  the  Tampico  territory — 
south  and  west  of  that  Gulf  port — are  capable 
of  producing  200,000  barrels  of  oil  daily.  At 
least  half  this  amount  is  credited  to  the  big 
Potrero  gusher  of  the  Pearson  interests.  With 
the  completion  of  a  contract  for  a  second  oil- 
depot,  at  Kilometre  5  on  the  Tamiahua  lagoon, 
the  Doheny  interests  will  have  storage  for 
10,000,000  barrels.  The  contract  is  for  one 
hundred  55,000-bbl.  steel  tanks,  and  the  tanks 
.  are  being  erected  at  the  rate  of  one  every 
three  days.  The  construction  of  a  10-in.  pipe- 
line from  the  Doheny  wells  in  the  Juan  Ca- 
siano  field  to  this  depot  has  been  commenced. 
The  Texas  Oil  Co.  haslet  a  contract  for  sixty 
55,000-bbl.  steel  tanks,  and  has  surveyed  a 
pipe-line  from  its  proposed  depot  on  thePanuco 
river  to  the  Topila  and  Panuco  fields.  It  is 
reported  that  the  Doheny  interests  have  in 
prospect  an  important  contract  for  crude  oil 
with  the  Hamburg-American  Steamship  Co. 
The  Electra  Syndicate,  of  London,  recently 
brought  in  a  well  in  the  Topila  field. 

Conchos  Power. — The  Mexican  North- 
ern Power  Co.,  a  Canadian  concern,  has 
more  than  1000  men  at  work  on  the  Conchos 
river  dam  and  reservoir  in  the  States  of  Chi- 
huahua. Scarcity  of  labour  during  the  period 
of  the  revolution  delayed  the  work.  Water 
will  be  stored  along  the  course  of  the  Conchos 
river  for  a  distance  of  30  miles,  and  the  power 
generated  will  be  transmitted  to  the  Parral, 
Santa  Barbara,  Naica,  Santa  Eulalia,  and 
other  important  mining  districts  of  Chihua- 
hua, as  well  as  to  the  Chihuahua  capital  and 
other  cities.  The  enterprise  is  expected  to 
result  in  greatly  reduced  mining  and  milling 
costs  in  the  districts  supplied  with  power.  It 
is  estimated  that  the  company's  plans  will  re 
quire  fully  15,000,000  pesos. 

Railroad  to  Bolanos. — English  capital- 
ists have  become  interested  in  plans  for  a  rail- 
road from  Zacatecas,  or  a  point  near  there,  on 
the  Mexican  Central  line  of  the  merger  sys- 
tem, to  the  old  Bolanos  mining  district  in 
northern  Jalisco.  It  is  said  that  should  the 
coming  year  open  with  a  promise  of  permanent 
peace  in  Mexico  these  plans  will  be  matured. 
The  famous  old  silver  mines  of  Bolanos  were 
acquired  in  1910  by  the  Bradbury  interests  of 
Los  Angeles,  California,  owners  of  the  Tajo 


OCTOBER,    1911 


273 


mines  in  the  Rosario  district  of  Sinaloa,  and 
the  Mexican  Mines  Co.  was  organized  to  re- 
open and  operate  them.  A  railroad  would  re- 
sult in  a  mining  revival  in  the  Bolafios  dis- 
trict, which  ranked  for  many  years  as  one  of 
the  most  important  in  Mexico. 

CAMBORNE. 

Levant.  —  For  the  16  weeks  ended  Sep- 
tember 2,  this  mine  showed  a  profit  of  ^2430, 
which  compares  with  ;^3355  for  the  previous 


per  ton,  as  compared  with  33s.  4d.  last  time. 
It  is,  however,  useless  to  make  comparisons 
of  working  costs  from  account  to  account,  for 
annual  charges  are  placed  against  income 
when  they  are  paid,  instead  of  being  spread 
over  the  whole  year.  The  profit  being  ^2430, 
and  ;^1528  having  been  brought  forward, 
there  was  a  balance  of  ^3958  available  for 
dividend.  When  Frank  Freathey  Oats,  the 
chairman,  announced  that  the  committee  only 
recommended  a  dividend  of   10s.  per  share, 


ON    THE    WAY    TO   A    MEXICAN    MINE. 


four  months.  The  amount  of  ore  treated  was 
7919  tons,  as  against  8566  tons,  and  the  total 
receipts  per  ton  of  ore  were  41s.,  the  same  as 
in  the  previous  account.  The  reduced  profit 
is  therefore  clearly  due  to  the  decreased  ton- 
nage, seeing  that  the  average  price  realized 
for  the  black  tin  showed  only  a  reduction  of 
a  few  shillings  per  ton.  I  notice  that  the 
chairman  stated  that  the  produce  from  tin 
was  down,  but  according  to  the  accounts  that 
was  offset  by  the  increased  value  of  by-pro- 
ducts, especially  arsenic.  The  expenditure 
for  the  16  weeks  was  ^13,793,  or  34s.  9d. 


absorbing  ^1177,  and  leaving  /'2781  to  be 
carried  forward,  some  of  the  shareholders  of 
the  old  school,  whose  policy  is  to  divide  pro- 
fits up  to  the  hilt  and  make  calls  to  meet 
losses,  were  quite  staggered,  but  fortunately 
the  wiser  policy  prevailed.  The  present  lease 
on  the  property  expires  in  four  years,  and 
forced  as  they  probably  will  be  by  pressure 
from  the  lords,  when  granting  a  new  lease,  to 
a  heavy  expenditure  on  plant  at  surface  for 
cheapening  production  and  reducing  labour  to 
a  minimum,  and  also  with  the  prospect  of 
having  to  sink  the  new  vertical  shaft  to  facili- 


274 


THE    MINING    MAGAZINE 


tate  cheap  working  underground,  and  to  en- 
able the  men  to  get  to  and  from  their  work 
quickly,  it  would  have  been  folly  on  the  part 
of  the  committee  not  to  conserve  their  re- 
sources. 

Wheal  Kitty.— This  successful  little  mine 
is  at  present  under  a  cloud.  The  grade  of  the 
ore  has  fallen,  and  according  to  the  sales  at 
the  ticketing  the  recovery  is  now  only  a  little 
over  20  lb.  per  ton,  so  that  the  expenses  are 
dangerously  near  the  receipts.  However, 
St.  Agnes  is  the  district  of  surprises,  and  the 
sett  is  in  the  centre  of  what  has  been  proved 
to  be  a  rich  mineral  belt,  and  it  will  be  sur- 
prising if  the  development  work  does  not  re- 
sult in  another  good  bunch  being  found.  The 
lode  referred  to  by  the  chairman  at  the  iast 
shareholders'  meeting  as  having  been  dis- 
covered in  the  540  cross-cut  south  from  Sara's 
shaft,  has  unfortunately  been  in  disturbed 
country  ever  since.  Three  slides  have  been 
already  met,  but  it  is  hoped,  when  settled 
ground  is  reached,  that  the  lode  will  resume 
at  least  the  same  value  as  when  it  was  first 
cut.  The  pitwork  in  Sara's  shaft  is  not  quite 
complete,  the  delay  in  finishing  this  work 
being  due  to  the  non-delivery  by  the  local 
foundry  of  essential  parts.  Another  month 
•or  so  should  see  this  work  completed,  when 
sinking  is  to  be  vigorously  resumed  to  inter- 
sect the  main  or  Wheal  Kitty  lode,  which 
has  been  the  objective  since  the  inauguration 
of  the  company. 

Botallack. — I  hear  that  in  draining  the 
old  mine,  large  quantities  of  broken  ore  have 
been  discovered,  and  that  Frank  Merricks 
is  proceeding  to  the  mine  to  inspect.  If  his 
report  confirms  the  manager's  estimates,  the 
company  will  be  able  to  stop  treating  waste 
heaps,  and  keep  the  mill  fully  employed  on 
mine  ore  of  fair  grade.  The  ore  discovered  is 
in  the  stuUs  and  has  been  presumably  left 
behind  when  this  part  of  the  mme  was  being 
worked  for  copper. 

West  Kitty. — It  is  pleasant  to  be  able  to 
report  a  hopeful  discovery  of  ore  at  the 
Wheal  Friendly  section  of  West  Kitty.  In 
the  deepest  part,  the  80  fm.  cross-cut,  the 
West  Kitty  lode  has  been  cut,  and  is  found 
to  be  6  ft.  wide  and  to  assay  100  lb.  per  ton. 
In  all  probability  the  lode  will  be  lost  for  a 
time,  owing  to  the  disturbance  by  the  main 
cross-course,  but  by  sinking  the  shaft  deeper 
it.  will  again  be  found.  T.  H.  Frisk,  Jr., 
has  done  much  good  work  at  this  mine  and 
fully  deserves  the  success  which  now  appears 
in  store.  The  discovery  will  be  encouraging 
to  the  neighbouring  mine,  Wheal  Kitty,  be- 


cause it  is  for  this  lode  that  the  new  Sara's 
shaft  is  being  sunk. 

Wheal  Coates. — Last  month  I  mentioned 
that  this  property  at  St.  Agnes  is  being  kept 
unwatered  to  the  50  fm.  level,  awaiting  the 
provision  of  additional  capital.  The  owners 
are  now  erecting  a  permanent  pumping  plant, 
and  have  already  purchased  from  Wheal  Merth 
a  horizontal  compound  engine  equal  to  a  60 
inch  Cornish  engine. 

The  Prince  of  Wales  mine  at  Calstock, 
in  East  Cornwall  is  being  worked  on  a  small 
scale,  and  capital  has  been  raised  for  the  pur- 
pose of  developing  a  lode  found  recently.  It 
is  reported  that  1000  tons  of  ore  from  this  lode 
has  yielded  20  tons  of  concentrate.  Josiah 
Paull  and  William  Thomas  have  made  in- 
spections of  the  mine,  and  both  have  written 
favourable  reports.  I  hear  that  the  Drakewalls 
in  the  same  district  is  to  be  given  another  trial. 

Basset  &  Grylls. — This  mine  at  Wendron 
is  temporarily  closed,  and  an  effort  is  being 
made  to  raise  further  capital  for  the  purpose 
of  sinking  the  shaft  another  20  fm.,  opening 
a  level  at  this  depth,  and  cross-cutting  to  in- 
tersect the  W^heal  Cock  lode.  This  mine  is  a 
promising  venture,  and  it  would  be  a  pity  if 
its  development  was  not  continued,  seeing  that 
so  much  money  has  already  been  spent.  Un- 
fortunately too  much  capital  has  been  sunk  on 
dressing  plant,  before  the  underground  de- 
velopment has  v/arranted  it. 

MELBOURNE. 

Broken  Hill. — Most  people  are  now  satis- 
fied that  the  new  orebody  found  in  the  British 
mine  in  the  neighbourhood  of  Thompson's 
shaft  is  an  important  one.  The  estimates  of 
content  vary  from  800,000  to  1,250,000  tons. 
Should  the  diamond-drill  at  the  No.  3  level 
intersect  the  orebody,  a  considerable  increase 
will  be  made  in  these  figures.  An  important 
development  has  been  at  the  bottom  (No.  9) 
level,  where  the  orebody  has  been  proved  for 
80  ft.,  the  ore  being  of  splendid  average  quality. 
Details  as  to  assays  are  not  available,  but  it  is 
generally  believed  that  the  content  runs  16% 
lead  and  zinc,  and  about  9  oz.  silver  per  ton.  If 
this  estimate  be  correct  then  indeed  the  com- 
pany has  added  so  much  to  its  ore  reserve  as 
to  give  it  a  new  mine. 

For  years  the  great  trouble  at  the  Barrier 
in  connection  with  flotation  processes  has 
been  the  treatment  of  slime.  The  Minerals 
Separation  has  made  the  greatest  progress  in 
this  direction  by  combining  the  use  of  oil  and 
acid  in  a  heated  solution.  Now  it  is  publicly 
stated  that  the  Amalgamated  Zinc  is  experi- 


OCTOBER,    1911 


275 


meriting  with  an  adaptation  of  the  hot  sul- 
phuric acid  process  as  developed  on  the  Bro- 
ken Hill  Proprietary  mine.  The  chairman 
of  the  latter  company  when  speaking  at  the 
annual  meeting  of  the  shareholders  a  few 
days  ago  stated  that  the  process  was  working 
well  and  that  it  had  been  decided  to  install 
a  new  plant  for  dealing  with  the  slime.  The 
Amalgamated  Zinc  washes  the  zinc  residue 
free  of  slime,  but  if  it  can  handle  slime  with 
this  hot  acidulated  solution  so  much  the  bet- 
ter. The  way  this  company  came  into  the 
business  is  that  it  had  an  option  on  the  Potter 
process,  which  was  the  original  in  Australia 
of  the  hot  acidulated  solution  method.  Liti- 
gation in  respect  to  these  processes  is  still 
going  on  ;  the  latest  victory  is  that  of  the 
Potter  company  with  respect  to  a  claim  it  had 


( 

Dre  Treated 

1906. 

1911. 

Yearly. 

Tons. 

Tons. 

Tons. 

Proprietary 

3,500,000 

2,250,000 

125,000 

Block  10 

1.000,000 

555,000 

100.000 

Central 

3,623,000 

3,600,000 

230,000 

South 

1,400,000 

3,500,000 

330,000 

South  Blocks.... 

400,000 

500,000 

120,000 

North  

600,000 

1,500,000 

260,000 

Junction   

200,000 

300,000 

— 

Junction   North. 

124,000 

350,000 

150,000 

British 

600,000 

800,000 

150,000 

Block  14  

220,000 

220,000 



11,667,000 

13,475.000 

... 

The  remarkable  fact  about  these  figures, 
which  are  certainly  conservative,  is  that  the 
ore  reserves  have  increased  over  what  they 
were  five  years  ago,  despite  the  large  quan- 
tity of  sulphide  extracted  in  the  meantime. 
It  will  be  noticed  he  only  puts  the  ore  reserve 


One  Mile 
J4 


YZ 


34-1 


Broken  Hi  J! 
Proprietary 


Block 
14 


British 
Broken  Hill 


Central 
(Sulpiiide  Corp'n) 


THE    BROKEN  HILL    MINES. 

made  on  the  Sulphide  Corporation  to  answer  of  the  British  at  800,000  tons,  whereas  apart 

certain  interrogatories  in  connection  with  the  from  the  new  strike  the  company  had  450,000 

Minerals  Separation  process,  which  the  Sul-  tons  developed.     Another  point  that  is  shown 

phide    Corporation    employs.      The    Broken  is    that    the  grade  of  the  ore  declines   with 

Hill  companies  that  have  dumps  of  slime  for  depth.     As  demonstrating  the  growth  of  the 

sale  have,  as  a  result  of  the  progress  made  in  zinc  industry  on  the  Barrier,  he  gives  the  fol- 

the  treatment  of  that  elusive  material,  practi-  lowing  interesting  official  figures  : 
cally   all  contracted   for  the   disposal  of  all  *  ^Outp.u°"''    '  o^'. muf"^ 

such  material   at  exceptionally  good   prices.  £  i 

Consequently   no  one   was   surprised  at   the  1906 2,187,930      tl82,793 

meeting  of  the  South   Broken   Hill  comipany  ^Z:::":::::Z'.' '.'.'.    2,'o68,'983        443;609 

the  other  day  when  F.  C.  Howard,  the  man-  1909.!!"^!...............    2,082,306       763!229 

aging  director,  announced  that  this  important  1910 2,433,297        952,249 

mine  also  was  taking  into  consideration  the  *  Represents  export  values  (net), 

treatment  of  its  slime  ^  Includes  magnetic  separation  products. 

A  review  of  the  position  of  the  Broken  Hill  When  it  is  remembered  that  these  figures 

mines  has  been  prepared  by  the  Argus  repre-  represent  the  result  of  the  flotation  process  it 

sentative,  who  makes  the  following  computa-  can  be  seen  what  an  important  bearing  that 

tion  of  the  ore  reserves  at  the  different  mines  :  metallurgical  discovery    has  had  on   the   in- 


276 


THE    MINING    MAGAZINE 


dustry.     The  figures  were  given  after  a  per- 
sonal inspection  of  the  district. 

Queensland.  —  The  Chillagoe  company's 
statement  of  accounts  is  in  one  way  satisfac- 
tory ;  but  in  another  it  calls  for  comment. 
The  net  profit  shown  is  under  ;^1 1,000.  This 
represents  the  returns  from  two  railway  sys- 
tems and  a  metallurgical  business.  On  the 
face  of  it  such  figures  appear  poor,  though  it 
has  to  be  remembered  that  the  company  has 
spent  ir36,000  during  the  twelve  months  in 
exploratory  work  on  different  minmg  proposi- 
tions which  were  offered  to  it  for  purchase.  It 
acquired  some  of  these  properties  and  these 
now  stand  in  the  books  of  the  company  at 
nothing,  as  the  whole  of  the  cost  was  written 
off  in  the  ;^36,000  just  mentioned.  The  earn- 
ings on  working  account  really  amounted  to 
over  ;^90,000,  so  that  from  the  industrial  side 
the  company  did  well.  It  has  of  course  a 
large  debenture  debt,  against  which  the  holders 
have  the  security  of  the  company's  railways 
and  works.  The  railways  have  given  the  com- 
pany control  of  a  large  area  in  Queensland.  It 
is  a  mineral-bearing  country  and  is  far  from 
having  been  thoroughly  developed.  There- 
fore the  policy  of  using  the  funds  of  the  com- 
pany in  testing  various  properties  is  a  good 
one,  and  a  single  rich  mine  would  repay  the 
whole  of  the  outlay  many  times  over.  It  is 
in  this  light  that  the  directors  of  the  company 
view  the  future  of  the  organization.  In  their 
eyes  to  stand  still  means  to  go  backward.  At 
the  same  time  they  have  decided  to  curtail  ex- 
penditure in  the  Etheridge  district.  What  they 
are  doing  now  is  to  develop  the  coal  resources 
in  the  Mount  Mulligan  district,  which  will  pro- 
vide cheap  fuel  and  so  make  a  tremendous  re- 
duction in  smelting  costs. 

The  most  interesting  piece  of  news  in  re- 
gard to  copper  mining  in  North  Queensland 
is  that  a  scheme  is  on  foot  for  the  amalgama- 
tion of  the  Hampden  and  Mount  Elliott  com- 
panies. We  in  Australia  think  that  we  are 
able  to  manage  mines  better  and  are  freer 
from  Stock  Exchange  influences  than  direc- 
torates in  London.  If  it  was  felt  that  such  an 
amalgamation  would  vest  the  control  of  the 
combined  properties  in  Australian  hands,  such 
a  scheme  would  have  general  support  here. 
It  is  recognized  that  the  management  of  the 
Mount  Elliott  mine  of  late  has  been  efificient, 
and  that  it  would  be  a  gain  to  both  properties  to 
have  the  cash  resources  of  the  Mount  Elliott 
applied  to  the  development  of  the  claims  held 
by  the  Hampden,  also  that  it  would  be  of  ad- 
vantage to  the  Hampden  to  be  able  to  flux  its 
ores  with  those  of  the  Mount  Elliott.     A  fur- 


ther advantage  would  be  that  the  two  com- 
panies would  not  compete  for  any  outside  pro- 
perties of  promise  that  may  be  discovered  by 
prospectors.  The  Hampden  company  has  just 
acquired  the  Trekelano  claim  on  advantageous 
terms,  and  developments  are  most  promising. 
Then  again  such  an  amalgamation  would  en- 
able control  to  be  exercised  over  outside  com- 
panies like  the  Hampden  South  Consols  and 
the  MacGregor,  while  if  the  railway  was  ex- 
tended to  Mount  Cuthbert,orecould  be  shipped 
thence  to  central  smelters  at  Mount  Elliott  or 
Hampden.  Furthermore  the  question  of  the 
concentration  of  the  low-grade  ores  has  to  be 
considered,  and  it  is  thought  by  some  of  the 
directors  of  the  different  companies  that  this 
could  be  undertaken  by  a  strong  amalgamated 
concern.  So  it  will  be  seen  that  there  are  in- 
teresting problems  ahead  for  those  leading  the 
way  in  North  Queensland  copper  mining. 

Bullfinch. — The  people  on  this  side  of  the 
world  are  intensely  amused  at  the  course  of 
events  in  connection  with  the  Bullfinch  dis- 
trict. Thanks  to  the  sturdy  attitude  of  the 
Melbourne  Press,  Victorians  kept  out  of  the 
Bullfinch  boom,  while  in  Adelaide  the  people 
went  nap  and  lost  their  money.  The  Bull 
Ant  arrangement  is  regarded  as  an  exceedingly 
sagacious  deal,  whether  intended  to  be  so  or 
not.  As  matters  stand  in  the  \^ictorian  mar- 
ket, Bullfinch  stocks,  unless  dealing  is  promp- 
ted from  Adelaide,  are  a  dead  letter.  Of  course 
Bullfinch  Proprietary  may  astonish  its  sup- 
porters and  the  public,  but  so  far  the  indica- 
tions in  that  direction  have  not  been  such  as 
to  induce  large  buying  on  this  side  of  the 
world. 

Victoria. — Gold  mining  in  \'ictoria  unfor- 
tunately shows  few  signs  of  revival,  but  there 
seems  to  be  a  chance  for  deep  alluvial  mining 
in  the  New  Langi  Logan  lead  near  Ararat. 
This  district  in  the  early  days  was  an  important 
producer  of  gold,  over  280,000  oz.  being  won 
in  one  year  from  shallow  workings.  The  leader 
in  the  district  at  the  present  time  is  the  Cath- 
cart,  which  is  working  on  a  tributary  lead. 
The  New  Langi  Logan  company  is  making 
for  the  main  gutter  and  within  a  short  time 
will  be  boring  with  the  object  of  draining  it, 
so  that  rising  into  the  wash  may  be  started. 
If  gold  is  obtained  in  sufficient  quantity,  there 
will  be  a  big  revival  in  the  district.  This  is 
most  desirable  in  view  of  the  suspension  of 
work  at  the  Berry  United  claim  near  Creswick. 
The  latter  is  the  claim  lowest  down  the  famous 
Berry  gutter,  in  which  so  much  English  capi- 
tal was  wasted.  The  Berry  United  has  been 
unable  to  find  profitable  gravel  and  so  has  been 


OCTOBER,    1911 


277 


closed  down.  Over  a  million  of  British  capital 
has  been  spent  in  Victoria  in  deep-lead  mining 
with  no  result.  The  fact  is  that  the  English- 
man came  too  late  in  the  day. 

Tasmania. — Mining  results  at  Mount  Lyell 
for  the  past  two  months  have  not  been  alto- 
gether satisfactory.  There  has  been  some  de- 
cline in  the  grade  of  the  ore  at  the  North  Lyell 
mine  and  consequently  the  copper  output  has 
been  afifected.  The  company  is  exceedingly 
reserved  in  respect  to  the  pitch  of  the  shoot  of 
ore  at  the  bottom  level  of  the  North  Lyell 
mine.  The  most  is  made  of  this  fact  by  the 
shareholders  of  the  Mount  Lyell  Blocks  Co. 
which  owns  the  adjoining  claim.  Even  if  the 
latter  should  get  the  shoot  of  ore  it  is  hardly 
possible  that  it  could  do  more  than  arrange 
terms  with  the  Mount  Lyell  Co.,  because  that 
company  has  the  only  tiuxes  available  in  that 
part  of  Tasmania. 

So  far  as  tin  mining  goes  the  Briseis  com- 
pany is  doing  good  work.  The  yield  from 
Krushka's  Flat  promises  to  be  satisfactory  and 
to  maintain  the  output  until  the  Ringarooma 
claim  can  be  developed.  At  the  latter,  progress 
is  being  made  with  the  removal  of  the  basalt 
overburden.  Tinmininggenerallyison  a  good 
footing,  owing  to  the  high  price  of  the  metal. 

NEW  YORK. 

Uneasiness  over  business  conditions  con- 
tinues widespread.  In  the  main  it  must  be 
attributed  to  uncertainty  as  to  the  future,  par 
ticularly  as  regards  tariff  and  trust  legislation. 
So  far,  both  Congress  and  the  Courts  have 
been  much  less  radical  than  might  fairly  have 
been  anticipated,  but  with  a  general  spirit  of 
investigation  and  reform  in  the  air,  no  one 
knows  exactly  upon  what  basis  to  plan  future 
business.  Therefore  no  one  commits  himself 
m,ore  than  is  necessary,  and  new  ventures  con- 
tinue to  be  neglected.  Actual  conditions  are 
much  better  than  generally  recognized.  In 
August  the  pig-iron  production  was  62,150 
tons  per  day  as  against  57,841  for  July,  and 
these  figures  are  representative.  In  the  last 
three  months  the  much  discussed  copper  sur- 
plus has  been  reduced  32,554,431  lb.  As  new 
copper  mines  come  into  production  old  ones 
drop  out  and  prices  have  even  risen  a  little. 
Bank  clearances  are  good  and  bank  balances 
continue  to  increase.  One  of  the  big  Chicago 
banks  now  has  on  deposit  the  largest  amount 
in  its  history  and  the  same  is  true  of  many 
others.  In  that  same  city,  in  the  down-town 
district,  11  modern  buildings  are  now  being 
erected  and  into  them  will  go  67,000  tons  of 
steel  alone.     Permits  have  been  issued  for  8 


more  buildings  calling  for  40,000  tons  of  steel 
and  costing  $17,000,000.  Such  an  amount  of 
new  construction  of  one  type  in  one  city  indi- 
cates that  conditions  are  far  from  bad.  None 
the  less,  it  is  true  throughout  the  country  as 
a  whole  that  new  enterprises  are  not  being 
undertaken.  The  trouble  seems  to  be  that 
money  as  it  accumulates  is  being  hoarded.  It 
is  the  common  belief  among  bankers  that  large 
sums  are  being  put  into  safe-deposit  vaults 
instead  of  into  banks.  The  people  seem  never 
to  have  recovered  from  the  distrust  of  finan- 
cial magnates  engendered  by  the  '  rich  man's 
money  panic'  of  1907.  It  must  be  admitted 
that  the  magnates,  too,  are  more  than  half  sus- 
pected of  withholding  money  from  sound  en- 
terprises in  order  to  influence  public  opinion 
regarding  legislation  and  regulation. 

Michigan  is  a  State  sharply  divided  into 
two  parts,  known  respectively  as  the  Upper 
Peninsula'  and  the  '  Lower  Peninsula.'  The 
latter  is  a  rich  farming  and  manufacturing 
region.  The  former  is  sparsely  settled  and 
the  chief  industry  is  the  mining  of  copper  and 
iron.  Not  unnaturally,  the  people  of  the  two 
parts  of  the  State  are  divided  on  many  ques- 
tions and  the  matter  of  taxation  is  one  con- 
cerning which  there  have  been  many  differ- 
ences of  opinion.  The  farmers  in  the  southern 
part  of  the  State  have  heard  much  of  the 
$1 15,000,000  in  dividends  paid  by  Calumet  & 
Hecla  and  little  of  the  cost  of  mining.  It  is 
difficult  therefore  for  them  to  believe  that  the 
mines  contribute  their  fair  share  toward  the 
expense  of  the  State.  Recently  the  State  Tax 
Commission  decided  to  call  in  an  outside  ex- 
pert to  examine  and  value  the  mines  of  the 
State  for  taxation  purposes,  and  J.  R.  Finlay 
was  chosen  for  the  task.  He  was  assisted  by 
William  Hague  and  H.  M.  Chance.  Mr. 
Finlay's  report,  which  was  made  public  late 
in  August,  has  created  intense  interest.  It  is 
not  too  mucn  to  say  that  no  such  report  has 
ever  before  been  issued  by  any  American 
State,  and  no  one  seems  to  know  exactly  what 
to  make  of  it.  Mr.  Finlay  has  applied  to  all 
the  mines  of  the  area  the  well-known  prin- 
ciples used  by  engineers  for  estimating  the 
present  value  of  properties  when  working  for 
private  clients.  The  result  is  dismay  on  both 
sides.  The  farmers  are  told  that  the  copper 
mines  when  rigorously  valued,  are  paying 
quite  their  full  quota  of  taxes,  while  the  mine- 
owners  are  told  that  their  properties  have  a 
present  value  of  only  about  60%  of  even  the 
present  depressed  stock-market  estimates.  It 
is  natural  for  everyone  to  think  more  of  the 
value  of  his  property  when  selling  shares  than 


278 


THE    MINING    MAGAZINE 


when  listing  it  with  a  tax -assessor,  and  still  it 
is  a  shock  to  have  the  two  valuations  put  side 
by  side.  Mr.  Finlay  refuses  to  consider,  for 
taxation  purposes,  the  stock-market  valuation, 
since  that  is  based  on  speculation.  He  also 
allows  nothing  for  plant,  since  the  latter  is  of 
little  or  no  value  when  the  ore  is  gone.  Fur- 
ther, he  allows  little  or  nothing  for  undeveloped 
property,  since  the  chance  of  making  a  dis- 
covery has  no  present  value.  Finally,  he  takes 
the  proved  and  probable  ore,  values  it  on  a 
basis  of  14-cent  copper,  discounts  the  total  for 
interest  according  to  the  number  of  years 
necessary  to  mine  and  market  the  copper, 
and  thus  arrives  at  the  present  value. 

Share  quotations,  which  seemed  to  have 
struck  bottom  at  the  end  of  August,  at  last 
penetrated  the  false  bedrock  and  kept  on  going 
down  until  late  in  September.     The  Steel  Cor- 
poration's securities  led  the  decline,  followed 
by  the  industrials  and  the  railroad  stocks,  and 
also  by  practically  the  whole  list  of  mining 
shares.     On  September  25,  for  example,  as 
compared  with  August  26,  Amalgamated  had 
dropped  10  points;  A.  S.  &  R.,  8| ;  Miami, 
2s  ;  Nevada  Consolidated,  if;   Ray,  If  ;  and 
Utah  Copper,  2*;  while  Chino,  Goldfield,  and 
Tennessee  Copper  practically  held  their  own. 
These  losses  fade  into  insignificance,  however, 
in  the  face  of  the  fall,  during  the  same  period, 
of  14  points  in  United  States  common,  and  of 
8f  in  the  preferred.    The  United  States  Steel 
Corporation  has  for  several  weeks  been  the 
centre  of  this  maelstrom.     During  the  closing 
days  of  the  last  Congressional  session,  an  in- 
vestigation of  its  methods,  with  special  refe- 
rence to  its  manner  of  absorbing  competitors, 
was  begun  by  the  Stanley  committee,  the  chair- 
man of  which  has  proposed  to  keep  at  the  task 
until  the  next  session.     Nothing  discreditable 
has  yet  been  revealed  beyond  what  has  long 
been  common  knowledge,  but  in  the  meantime 
rumours  have  been  flying  back  and  forth,  first 
to  the  effect  that  the  Government  was  going 
to  bring  suit  to  dissolve  the  corporation,  next 
that  the  corporation  was  going  to  oppose  any 
such  action,  then  that  it  was  planning  to  dis- 
solve itself,  and  so  on.     Finally  the  Attorney 
General  issued  a  platitudinous  statement  to  the 
effect  that  if  the  investigators  of  the  Depart- 
ment of  Justice  became  satisfied  with  evidence 
of  law-breaking,  it  would  be  his  painful  duty 
to  prosecute,  but  that  he,  personally,  would 
much  prefer  to  see  the  Steel  Corporation  and 
all  others  of  like  nature  reform  themselves,  and 
save  him  from  this  disagreeable  necessity.   To 
this,  the  leading  directors  of  the  Corporation, 
who  had  been  importuned  by  stockholders  and 


brokers  to  put  an  end  to  their  suspense,  re- 
sponded that  their  consciences  were  perfectly 
free  from  guilt,  that  the  Steel  Corporation  was, 
and  always  had  been,  most  considerate  of  its 
competitors  and  customers  alike,  and  that  its 
present  plans  included  nothing  in  the  direction 
of  dissolution,  either  voluntary  or  compulsory. 
Whereupon  the  price  of  steel  shares  started  to 
rise  again.  To  the  disastrous  consequences  of 
all  this  agitation  about  the  steel  trust  must 
be  added  the  discouraging  results  of  railroad 
operation  in  many  parts  of  the  country,  an- 
nouncements of  which  are  of  almost  daily  oc- 
currence. One  road, which  enjoys  an  absolute 
monopoly  of  traffic  in  the  Northeast,  reports 
a  deficit  of  $1,267,000  ;  this  its  president  at- 
tributes mainly  to  increased  wages,  which  it  is 
not  permitted  by  law  to  offset  by  raising  its 
rates.  This  railroad  is  underwriting  heavy 
outlays  for  new  construction  along  a  tributary 
road,  and  it  is  matter  for  conjecture  as  to  what 
part  of  this  deficit  may  be  due  to  the  generosity 
of  the  steel  corporation  in  permitting  the  rail- 
road to  pay  $28  for  the  same  identical  rails 
that  a  German  or  an  English  road  could  send 
here  and  buy  for  $20  per  ton. 

Governmental  interference  in  business 
is  universally  blamed  for  the  present  despon- 
dency.     In   conversation  with  a  well-known 
banker,  I  was  struck  with  the  bitterness  of  his 
tone  in  referring  to  what  he  stigmatized  as  a 
high-handed  attempt  of  the  Government   to 
pull  down  the  whole  business  structure  of  the 
country.     No  one  questions  the  propriety  of 
the  Government's  prosecution  of  offenders  in 
the  case  of  rebates,  and  conspiracies  to  defraud 
or  to  restrain  trade,  but  much  of  the  material 
progress  of  the  present  era  would  have  been 
impossible  without  a  certain  amount  of  con- 
solidation and  pooling  of  interests.     Such  in- 
nocent combinations  are  amply  justifiable  on 
economic  grounds,  but  in  the  eyes  of  the  Sher- 
man Act  they  are  illegal,  or  were  until  the 
recent  decision  of  the  Supreme  Court  mollified 
somewhat  the  stringency  of  the  law.   Criticism 
is  directed  not  only  at  the  imperfections  and 
impracticabilities  of  the  anti-trust  laws  but  also 
at  the  laxity  of  the  Government  during  recent 
administrations  in  seeking  to  enforce  the  law; 
if  more  diligence  (wuth  possibly  less  vocife- 
rousness)  had  been  shown  in  upholding  the  law 
during  the  first  ten  years  after  its  enactment, 
one    of    two    things    would    have    happened. 
Either  the  law  would  have  been  repealed  or 
made  more  practicable  before  this  time,  or  the 
more  voracious    trusts,  now^  so  belligerently 
attacked,  would  not  have  been  allowed  to  at- 
tain their  present  proportions. 


OCTOBER,    1911 


279 


PERSONAL 

A.  Chester  Beatty  sailed  for  New  York 
on  September  30. 

Hans  C.  Behr  and  A.  M.  Robeson  have 
been  taking  the  waters  at  Carlsbad. 

J.  M.  Bell  will  return  from  Siberia  in 
December. 

F.  W.  Bradley  has  returned  to  San  Fran- 
cisco from  Alaska. 

Juan  F.  Brandes  has  moved  from  Denver 
to  San  Francisco,  with  offices  in  the  Newhall 
Building. 

Henry  Brelich  has  gone  to  the  City  of 
Mexico. 

H.  Kenyon  Burch,  mechanical  engineer 
for  the  Miami  Copper  Co.,  is  in  California, 
recuperating  from  peritonitis. 

Charles  Butters  sailed  for  New  York 
on  October  11. 

J.  H.  Butters  has  been  appointed  chief 
engineer  for  the  Hydro  -  electric  Power  & 
Metallurgical  Co.  of  Tasmania. 

F.  T.  Byrde  has  returned  from  the  Gold 
Coast. 

T.  Lane  Carter,  now  a  resident  of  Chi- 
cago, is  at  Chihuahua,  Mexico. 

Charleton,  Dickinson  &  Co.  will  be 
dissolved,  A.  G.  Charleton  and  Arthur  Dickin- 
son continuing  in  practice  singly. 

Eugene  Coste,  lately  president  of  the 
Canadian  Mining  Institute,  is  in  London. 

J.  H.  Curle  is  at  Bagdad. 

Rowland  Feilding  has  arranged  to  sever 
his  partnership  in  Hooper,  Speak  &  Feilding, 
the  firm  returning  to  the  style  of  Hooper  & 
Speak. 

William  Frecheville  is  at  Cordoba, 
Spain. 

B.  L.  Gard'ner  went  to  Egypt  at  the  end 
of  September. 

W.  S.  GiFFORD  is  in  the  southern  part  of 
the  Red  Sea  oilfield,  Egypt. 

William  Gowland  has  been  elected  pre- 
sident of  the  Institute  of  Metals  for  1912. 

James  M.  Hall,  of  Chicago,  is  at  Porcu- 
pine. 

H.  W.  Hardinge  is  here  from  New  York. 

Frederick  Hellmann,  now  residing  at 
New  York,  and  formerly  general  manager  of 
I  the  East  Rand  Proprietary,  returns  to  New 
i       York  on  October  18. 

C.  A.  Heussler  has  returned  from  New- 
foundland. 

Howard  Hill  is  reporting  on  the  Forbes 
Reef  in  Swaziland. 
4—4 


C.  Baring  Horwood  returns  to  the  Rand 
on  October  21. 

W.  H.  Hosking  is  examining  a  copper 
mine  in  the  Shetland  islands. 

C.  E.  Hutton  is  returning  to  South  Africa, 

C.  J.  Inder  has  returned  from  the  Ural 
mountains. 

W.  R.  iNGALLS,  the  editor  of  the  En- 
gineering and  Mining  Journal,  is  making  a 
tour  through  the  western  mining  regions  of 
the  United  States. 

E.  H.  Johnson,  chief  metallurgist  to  the 
East  Rand  Proprietary,  is  on  his  way  back 
to  Johannesburg. 

George  Macfarlane  sailed  for  West 
Africa  on  September  27. 

James  A.  Mactear  also  sailed  for  West 
Africa  on  September  27. 

D.  P.  Mitchell,  manager  for  Bewick, 
Moreing  &  Co.  at  Melbourne,  is  in  London. 

James  W.  Neill  is  in  North  Carolina. 

F.  Douglas  Osborne,  on  the  conclusion 
of  professional  work  in  the  Swaziland  tinfields, 
paid  a  visit  to  the  tin  mines  in  the  Northern 
Transvaal. 

Fred  P,  Paul  sailed  for  Sydney,  New 
South  Wales,  on  October  2. 

Frank  H.  Probert  was  at  New  York 
recently. 

C.  W.  PuRiNGTON  is  expected  in  London 
from  Eastern  Siberia  on  November  10. 

T.  H.  Retallack  has  gone  to  Peru  on 
behalf  of  the  Cuta  Syndicate. 

Alexander  P.  Rogers  passed  through 
London  on  his  return  from  Brazil  to  New  York 

A.  W.  Ross,  of  Wellington,  New  South 
Wales,  passed  through  London  on  his  way  to 
the  Bibiani  goldfield.  West  Africa. 

G.  H.  Rotherham  is  now  with  the  Bantjes 
Consolidated  Mines  at  Florida,  in  the  Trans- 
vaal. 

W.  N.  RuNDALL  has  returned  from  South 
Africa. 

W,  H.  Shockley  is  at  Lucerne. 

A.  L.  Simon  is  again  in  the  Ural  region. 

Thos.  B.  Stearns  left  London  for  Denver 
on  September  21. 

O.  J.  Steinhart,  of  Twite  &  Steinhart, 
has  gone  to  Swedish   Lapland. 

R.  C.  N.  Twite  is  in  Roumania. 

J.  C.  Vivian  has  returned  from  the  Argen- 
tine. 

P.  B.  Waugh  has  returned  from  Austria. 

H.  E.  West  has  arrived  from  California, 
after  a  visit  to  Porcupine. 

Louis  A.  Wright  is  making  a  journey 
across  Asia. 


THE  FINANCE  OF  A  MINE.    V. 

By  M.  H.  BURNHAM. 


THOSE  who  have  read  the  preceding 
articles  will  have  noticed  that  the  whole 
theory  of  valuation  advanced  is  the 
simple  development  of  two  business  concepts, 
namely  : 

(a)  The  rate  of  interest  expected  from  any 

investment  is  in  inverse  proportion 
to  the  risk  thought  to  exist. 

(b)  Any  investment  entails  the  assumption 

of  a  capital  return,  say,  3%,  as  the 
rate  realized  from  securities  involv- 
ing no  risk,  and  a  further  rate  as  an 
allowance  for  additional  risk,  count- 
ing from  the  date  of  investment. 
The  first  premise  (a)  and  the  last  clause  of 
(b)  have  a  practical  significance  often  over- 
looked when  considering  the  construction  of  a 
financial  enterprise. 

For  instance  :  an  engineer  on  the  geologi- 
cal evidence  before  him  will  allow  perhaps  a 
shoot-extension  of  100  ft.  on  the  dip  as  ore 
for  which  he  is  willing  to  advise  payment. 
Yet  few  engineers  seem  to  realize  that 
the  difference  between  the  present  value  of 
the  blocked  ore  and  the  share  value  of  the 
company  is  their  real  allowance  for  shoot- 
extension.  As  this  amount  has  not  only  to 
be  redeemed,  but  an  interest  must  be  paid 
commensurate  with  the  risk,  the  amount  of 
shoot-extension  actually  allowed  by  the  re- 
sponsible engineer  is  often  startling. 

Table  IV  was  compiled  with  a  view  to  set- 
ting out  current  practice  in  the  matter  of  the 
finance  of  shoot-extension,  but  as  the  data 
touching  the  deferment  factors  were  wanting, 
the  extension  necessary  to  redeem  the  capital 
was  alone  considered.  As,  however,  no  one 
invests  to  have  his  capital  only  returned,  cal- 
culations neglecting  the  risk  and  deferment  of 
return  are  misleading. 

Fig.  5,  illustrating  the  typical  copper  mine, 
will  make  this  clearer.  The  engineer  is  per- 
haps willing  to  allow  a  shoot-extension  to  the 
line  tt,  but  the  capital  of  the  company  less  the 
present  value  of  the  blocks  really  means  an 
allowance  to  vv,  essentially  committing  the 
engineer  to  a  shoot-extension  far  beyond  that 
intended  :  in  this  case  into  the  zone  of  primary 
ore. 

The  number  of  levels  of  shoot-extension  in- 
volved by  the  capitalization  may  be  expressed 
by 


Formula  VIII. 

=  r   +  r    -T  r      -r  r 

=  (7  +  r'  +  r"'Y   (r'  +  r"  +  r'") 


=  (/  +  /+  r'") 


"'\d 


+  r 


where  D  is  the  annual  dividend  in  percentage 
of  the  capital  remaining,  after  subtracting  the 
present  value  of  the  reserve  above  the  lowest 
level, 

r'     =  the  Consol  rate,  or  3%. 

r"  =  rate  necessary  to  redeem  the  capital 
in  ky  years. 

r'"   =  the  risk-rate  determined  upon. 

r""  =  the  rate  necessary  to  make  good  the 
loss  of  interest  due  to  delayed  divi- 
dends. 

k      =  the  number  of  years  of  life  to  a  level 

y  =  the  number  of  levels,  or  the  unknown 
factor, 

d  =  the  years  of  delay  in  realizing  divi- 
dends (not  counting  the  first  year). 

Of  the  mines  set  out  in  Table  IV  the  Santa 
Gertrudis  is  the  only  one  the  reports  of  which, 
issued  at  the  time  of  flotation,  are  available, 
hence  this  case  will  serve  to  illustrate.  The 
first  dividend  will  have  been  delayed  one  year, 
and  taking  the  life  of  the  reserves  above  the 
lower  level  at  two  years  yielding  ^250,000  per 
year  on  a  capital  of  ^1,275,000;  also  allow- 
ing a  uniform  risk-rate  of  5%  on  these  blocks, 
their  present  value  will  be  (0'85734  x  250,000) 
+  (079383  X  250,000)  =  ;^413,000.  (See 
Table  VI). 

This  sum  taken  from  ^1,275,000  leaves 
^862,000  to  come  from  below  the  lowest 
level,  and  will  be  deferred  three  years. 

As  the  economic  shoot  works  out  at  4000 
sovereign-feet  and  the  crushing  plant  is  esti- 
mated to  crush  160,000  tons,  or  exhaust  one 
level  each  year,  this  means  a  return  of  46% 
on  the  remaining  capital. 

Allowing  a  uniform  risk-rate  of  10%  for 
these  lower  levels,  manifestly  too  low  but 
sufficient  for  illustrative  purposes,  trial  and 
error  substitution  in  Formula  VIII  gives  y  a 
value  of  5  :  that  is,  the  shoot-extension  allowed 
by  the  above  capital  is  really  500  ft.  Even  if 
a  risk-rate  of  5% for  the  lower  levels  be  allowed, 
the  shoot-extension  is  nearly  400  feet. 

The  above  results  may  be  obtained  without 
calculation  by  referring  to  Table  \ll,  where 


280 


OCTOBER,    1911 


281 


Table  VII. 

r"  or  RISK-RATE  =  70%. 

Real  or  Present  Value  of  £l  or  $1  of  Annual  Profit  in  Block. 

Rate  to  be  Realized  (s)  =  13%. 


Years  of  delay  id) 
in  realizing  divi- 

Life of  Block  (n)  in  Years. 

dends  from 
block. 

1 

2 

3 

4 

5 

0 

1 

2 
3 
4 
5 

0*88496 
0*78315 
0*69305 
0*61332 
0*54276 
0*48032 

1*60614 
1*42136 
1*25784 
1*11314 
0*98508 
0*87175 

2*20493 
1*95126 
1*72679 
1*52812 
1*35232 
1*19674 

2*70981 
2*39808 
2*12220 
1*87804 
1*66196 
1*47076 

3*14120 
2*77978 
2*46002 
2*17699 
1*92656 
1*70491 

Fig.    5.     PLAN    AND    SECTION    OF    A    TYPICAL    COPPER    MINE. 


282 


THE    MINING    MAGAZINE 


it  will  be  seen  that,  allowing  10%  for  risk  and 
deferring  3  years,  the  present  value  of  one 
pound  is  ;^2'17,  and  the  nearest  value  of  n 

corresponding  to  --—  or  2'22  is  5  years.    This 

will  be  clear  to  any  one  who  has  followed  the 
philosophy  underlying  the  earlier  formula. 

It  hardly  seems  too  much  to  say  that  if  the 
application  of  simple  business  principles  were 
more  generally  appreciated  by  those  engineers 
who  specialize  on  valuation,  our  position  as  a 
profession  would  be  more  satisfactory  in  the 
body  politic.  As  before  mentioned,  what  with 
an  excess  of  technique  in  the  curricula  of  tech- 
nical schools  and  the  pressure  of  flotational 
exigencies,  the  present  position  leaves  some- 
thmg  to  be  desired. 

VANADIUM  IN  NEW  MEXICO 

By  BRIGHAM  LEATHERBEE 

IN  1884,  F.  M.  Endlich,  manager  of  the 
Lake  Valley  mines,  which  lie  in  the  south- 
western portion  of  Sierra  county.  New 
Mexico,  and  were  famous  producers  of  silver 
ore  to  the  value  of  over  $14,000,000,  dis- 
covered in  the  lead  ore  of  these  properties, 
small  yellow  crystals  which  upon  examina- 
tion proved  to  consist  of  lead,  arsenic,  vana- 
dium, and  oxygen.  In  honour  of  the  dis- 
coverer, this  combination  was  named  End- 
lichite,  and  has  been  so  classed  by  Dana  and 
subsequent  mineralogists.  During  1896  or 
1897,  William  F.  Hall  discovered  the  same 
variety  of  vanadium  ore  in  the  lead  and  silver 
mines  he  was  operating  about  twenty  miles 
north  of  Lake  Valley,  and  which  have  since 
become  the  property  of  the  Vanadium  Queen 
Mining  Co.  As  there  was  no  commercial  de- 
mand for  vanadium  at  that  time,  Mr.  Hall 
preserved  only  the  finest  crystals,  which  he 
sent  as  specimens  to  a  large  mineral  company 
in  Philadelphia,  by  whom  they  were  distri- 
buted to  the  various  public  and  private  mineral 
collections  throughout  Europe  and  America. 

During  the  winter  of  1909,  vanadium  was 
discovered  on  the  properties  of  the  South- 
western Lead  &  Coal  Co.  on  the  eastern  slope 
of  the  Sierra  de  los  Caballos,  across  the  Rio 
Grande  and  40  miles  east  of  the  other  deposits. 
This  property  was  then  taken  over  by  the 
Vanadium  Mines  Co.,  which  is  now  operating 
it.  The  property  of  the  Vanadium  Queen 
Mining  Company  is  situated  in  the  Las  Ani- 
mas district,  which  has  heretofore  been  con- 
sidered a  gold  district,  as  but  little  else  has 
been  worked  here,  although  some  silver,  lead, 
and  manganese  have  been  mined.  The  total 
gold  production  from  both  quartz  lodes  and 


placer  workings  is  recorded  at  over  $9,000,000. 
The  vanadium  ore  occurs  in  a  well  defined 
contact  vein,  between  the  shale  and  lime, 
which  shows  numerous  outcrops  for  over  three 
miles  ;  a  number  of  prospecting  shafts,  open- 
cuts,  and  tunnels  indicate  that  there  is  a  con- 
tinuous orebody  for  this  entire  distance.  The 
vanadium  is  found  in  different  combinations, 
endlichite  and  vanadinite  predominating,  and 
the  assays  run  from  3"25  to  9%  in  metallic 
vanadium.  So  far  the  management  has  de- 
voted its  entire  attention  to  prospecting  along 
the  vein  and  to  opening  up  the  most  promising 
portions,  with  the  intention  of  having  the  ore 
well  blocked  out  before  commencing  actual 
operations.  In  the  meantime,  constant  ex- 
periments upon  the  treatment  and  reduction 
of  ores  have  been  under  way  in  various  metal- 
lurgical laboratories,  and  it  is  presumed  that 
shortly  the  first  unit  of  an  experimental  plant 
will  be  installed  upon  these  properties. 

The  Vanadium  Mines  Co.  controls  two  fis- 
sure veins  of  vanadium-bearing  ore,  one  of 
which  has  been  prospected  by  a  50-ft.  shaft, 
while  the  other  has  been  more  extensively  de- 
veloped and  now  has  the  main  shaft  down  be- 
low 200  ft.  with  various  levels.  The  ore  is 
hauled  from  the  mine  to  the  old  concentrating 
mill  of  the  defunct  coal  company,  which  mill 
has  been  enlarged  by  a  set  of  Cornish  rolls  and 
some  new  vanners  and  slime  tables.  This  con- 
centration is  being  performed  as  experimental 
work,  the  foundations  having  been  laid  for  a 
new  and  permanent  plant  to  be  equipped  with 
the  latest  patterns  of  the  best  machinery,  as 
soon  as  the  type  of  equipment  best  suited  for 
the  ore  has  been  selected.  After  concentration, 
the  concentrate,  which  assays  about  8'632% 
vanadium  and  59%  lead,  is  transported  by 
mule  teams  to  Cutter,  where  a  large  oxide 
plant  has  been  erected  on  the  Santa  Fe  rail- 
way. The  product  from  this  plant  is  shipped 
to  Rankin,  Pennsylvania,  where  it  is  made  into 
ferro-vanadium  alloy. 

Prospecting  is  being  done  elsewhere  in  the 
county  for  vanadium  and  there  are  many 
rumours  afloat  regarding  the  discovery  of 
valuable  deposits. 

The  Copper  Deposits  at  Alderley  Edge, 
Cheshire,  are  continually  being  examined  by 
mining  engineers,  who  hope  to  turn  to  advan- 
tage the  carbonates  contained  in  the  Keuper 
and  Bunter  sandstones.  These  deposits  have 
disappointed  many  workers  in  times  gone  by,  as 
the  copper  content  is  irregularandof  low  grade. 
Lancashire  chemical  manufacturers  have  tried 
extraction  by  various  acids  without  avail. 


OCTOBER,    1911 


283 


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8 

LOSSES    IN    CYANIDATION 


By  H.  FORBES   JULIAN. 


Introductory.— The  interest  manifested 
in  the  filtration  of  sHme,  especially  with 
reference  to  the  prevention  of  mysterious 
losses  of  gold  and  silver  during  cyanidation, 
has  of  late  been  much  intensified  by  sundry 
unfortunate  events.  The  fact  that  such  losses 
do  occur  is  beyond  doubt,  but  the  cause  as 
well  as  the  remedy  is  far  from  apparent.  It 
may  easily  be  proved  that  the  presence  of 
slime  accounts  for  much  of  the  loss,  which  in 
a  measure  is  preventible  by  the  aid  of  filters 
The  following  few  notes  touching  on  the 
more  important  uses  and  features  of  the 
vacuum  type  of  filter,  may  be  of  service  in 
opening  a  discussion  with  a  view  to  elucidat- 
ing matters. 

Preparation  of  Pulp  for  the  Filter. 
— There  are  various  sources  of  loss  in   the 
treatment    of    the  pulp   before   beginning   to 
separate  the  solution  from  the  solids,  but  it  is 
not  necessary  to  deal  with  these  other  than 
incidentally,  because  the  filter  is  capable  of 
augmenting  the  dissolving  treatment  and  prac- 
tically eliminating  these  sources  of  loss.     Suf- 
fice it  to  say  that  the  slime  is  mixed  with   so- 
lution in  the  proportion  of   1   ton  of  solid  to 
say  2  tons  of  liquid  (the  range  in  practice  is 
from   I2  to  3)  and  the  mixture  is  agitated, 
the  object  being  to  facilitate  the  dissolving  of 
the  gold  and  silver  by  constantly  changing  or 
circulating  the  solution  about  the  metal-bear- 
ing particles,  and  at  the  same  time  to  aerate 
the  pulp.     In  cases  where  the  slime  settles 
readily  when  agitation  is  stopped  the  pulp  is 
thickened,  before  it  is  passed  on  to  the  filter, 
by   decanting    the   supernatant   solution.      A 
pulp  having  a  consistence   of    about   1 :  1   is 
generally  desired  in  order  to  avoid  any  neces- 
sity for  agitation  while  filtering,  but  in  some 
cases  it  is  not  practicable  to  thicken  to  this 
extent  and  the  pulp  goes  to  the  filter  contain- 
ing as  much  as  3  of  solution  to  1   of  solid. 
When   filters   are  provided  with  means   for 
effecting  a  constant  circulation    of  the   pulp 
during  filtration  the  question  of  thickness  re- 
solves itself  into  one  of  economy.     When  the 
pulp  contains  less  than    1   of  liquid  to   1   of 
solid  it  is  not  sufficiently  mobile  for  econom- 
ical handling  ;  but,  of  course,  there  are  excep- 
tions to  this  rule.     The  coarser  the  slime  par- 
ticles the  less  solution  need  be  present. 

The  thickness  of  a  pulp   is  generally  ex- 


pressed by  the  ratio  of  solid  to  liquid,  which 
from  a  given  ore  is  conveniently  determined 
from  the  specific  gravity  of  the  pulp. 

Cake  Formation  and  Thickness.  — 
When  filtering  slime  containing  much  amor- 
phous clay  it  is  good  practice  to  apply  a  low 
suction  (about  one  quarter  of  the  maximum) 
until  the  cake  is  about  I  inch  thick  and  then 
the  higher  vacuum.  By  this  means  a  more 
permeable  cake  is  formed  than  if  the  higher 
vacuum  is  applied  at  the  start.  It  is  conse- 
quently more  quickly  washed,  that  is,  ex- 
hausted of  its  valuable  contents.  When  the 
slime  consists  chiefly  of  crystalline  material 
(tube-mill  product)  the  effect  of  the  low  suc- 
tion at  the  start  is  not  so  apparent,  but  it 
usually  results  in  a  clearer  filtrate.  Opera- 
tors as  a  rule,  however,  pay  little  attention  to 
this  variation  in  the  vacuum,  but  keep  it  con- 
stant during  cake-formation. 

The  thickness  to  which  a  cake  is  allowed 
to  build-up  is  governed  chiefly  by  economic 
considerations.  At  the  beginning  of  each 
cycle  of  operations,  when  the  filter-cloths  are 
clean,  the  solution  filters  through  readily,  and 
with  a  constant  vacuum  the  rate  becomes 
slower  and  slower  as  the  deposit  increases. 
A  point  is  reached  when  it  becomes  economi- 
cal to  stop  and  proceed  to  wash  and  discharge 
the  cake  and  start  the  cycle  again.  Exactly 
when  this  occurs  must  be  found  by  trial.  It 
naturally  varies  with  the  character  of  the 
slime  together  with  the  altitude  of  the  locality. 
In  some  cases  the  limit  is  reached  when  the 
cake  is  only  i  inch  thick,  as  when  dealing 
with  highly  amorphous  or  gelatinous  material, 
while  with  crystalline  silicious  slime  a  cake 
of  2  inches  and  even  more  may  be  economic- 
ally formed  before  beginning  to  wash. 

The  usual  way  to  find  when  the  cake  is  of 
the  desired  thickness  is  by  direct  measure- 
ment or  by  time  comparisons,  but  it  is  obvious 
that  the  rate  at  which  the  filtrate  is  withdrawn 
may  be  utilized  for  this  purpose  with  advan- 
tage. 

W^hen  using  a  constant  vacuum  the  rate  at 
which  the  cake  forms  is  shown,  graphically, 
by  the  parabolic  curves  in  the  annexed  dia- 
gram. Fig.  1.  It  will  be  noticed  how  the 
rate  rapidly  decreases  as  the  cake  thickens. 
Thus  in  the  first  ten  minutes  the  cake  forms 
six  times  as  rapidly  as  in  the  last  ten  minutes. 

284 


OCTOBER,    1911 


285 


10 


20 


30  40  50  60  70  60 

M  I  n  u  tes 

Fig.  1.     CURVES    SHOWING    THE    RATE    OF   FORMATION    OF    CAKES. 


90 


100 


z 

V 

19 

^ 

■— 

■ — 



16 

^ 

\ 

17 

\ 

16 

i_ 

\ 

■-  15 
0    ,  , 

\ 

\ 

/3 

c 

°/2 

\ 

\ 

t." 

•o 

I 

C^9 

\ 

0  0  7 

\ 

■O  0-6 

c 
3 

\ 

O05 

Q. 

\ 

0  4 

\ 

\ 

03 

\ 

-^ 

02 

^ 

0/ 

0 

/ 

0 

z 

0 

. 

w 

4 

0 

'0 

i 

W 

; 

0 

i 

10 

>u 

IL 

Percentage   oF   Water  drawn    rtirougti  Cake. 
Fig  2.     WATER-WASH   DILUTION. 


286 


THE    MINING    MAGAZINE 


For  example,  if  a  If  in.  cake  took  100  min- 
utes to  form,  over  in.  would  have  been  de- 
posited within  the  first  ten  minutes,  while  in 
the  last  ten  minutes  it  would  build  up  only 
T2  in.  Again,  if  the  cake  at  the  end  of  100 
minutes  was  only  I  in.  thick,  about  f  in.  would 
be  formed  in  the  first  50  minutes,  and  it  would 
take  another  50  minutes  to  add  4  inch. 

The  porosity  of  a  cake  is  affected  by  the 
pressure  of  formation.  Thus  a  cake  deposi- 
ted by  vacuum  contains  40  to  65  lb.  dry  ore 
per  cubic  foot,  according  to  the  specific  gravity 
and  fineness  of  the  material,  while  the  same 
material  filter-pressed  in  a  cake  contains  70 
to  110  lb.  dry  ore  per  cubic  foot. 

The  foregoing  considerations  supply  food 
for  thought  to  the  practical  investigator.  They 
give  an  insight  into  the  reason  for  the  well 
known  fact  that  high-pressure  filters,  when 
dealing  with  amorphous  slime,  produce  thin 
sloppy  cakes  from  which  the  metallic  con- 
tents cannot  be  economically  and  efficiently 
washed,  whereas  the  vacuum-filter  on  the 
same  material  forms  thick,  porous,  and  well 
dried  cakes  in  excellent  condition  for  washing. 

If  the  filter  is  to  be  used  simply  for  de- 
watering  or  drying, the  curvesshowgraphically 
how  much  more  economical  it  is  to  clean-oflf 
at  short  intervals  rather  than  at  long  intervals 
when  washing  is  employed.  This  is  particu- 
larly evident  with  the  so-called  continuous 
filters,  which,  of  course,  do  no  effective  wash- 
ing, but  simply  act  as  dewaterers. 

The  permeability  of  the  cake  adjusts  itself 
inversely  as  the  pressure  of  the  atmosphere 
plus  the  hydrostatic  head,  and  although  the 
cake  may  be  thicker  in  one  part  than  another 
it  will  allow  only  an  equal  fiow  of  solution  to 
pass  per  unit-area  of  the  cake.  It  is,  however, 
important  that  the  cakes  should  be  fairly  uni- 
form in  thickness  and  should  not  build-up  so 
as  to  allow  two  opposite  faces  to  touch  or 
freeze  '  together.  An  uneven  thickness  is  due 
chiefly  to  settling  and  is  most  apparent  when 
the  pulp  is  of  thin  consistence.  It  may  be  com- 
pletely avoided  by  agitating  or  circulating  the 
pulp  while  the  formation  of  cake  is  proceeding, 
but  if  the  pulp  is  sufficiently  dense,  say,  1  of 
solid  to  1  of  liquid,  little  or  no  trouble  is  likely 
to  arise  from  uneven  thickness. 

Characteristics  of  Filter-Cakes. — 
It  is  generally  accepted  that  cakes  of  slime 
formed  by  pressure-filters  differ  in  character 
from  those  formed  by  vacuum-filters,  although, 
as  is  obvious,  the  formation  of  both  is  due  to 
pressure,  the  difference  being  only  one  of  de- 
gree. It  may  be  that  this  difference  in  charac- 
ter is  also  only  one  of  degree.     In  practice  it 


has  often  been  shown  that  when  filtering  so- 
called  natural  slime  the  vacuum-filter  produces 
not  only  a  thicker  cake  but  one  that  is  more 
porous  and  more  uniform  in  its  porosity,  so 
that  it  can  be  more  efficiently  washed.  On  the 
other  hand,  when  dealing  with  fine  sand  or 
crystalline  slime  the  high-pressure  filter  pro- 
duces the  heavier  cake  in  a  given  time,  but  not 
heavier  in  proportion  to  the  power  expended 
and  not  so  uniform  in  its  porosity. 

The  cake  formed  on  the  vacuum-filter  con- 
sists of  an  infinite  number  of  layers  roughly 
parallel  to  each  other  and  the  washing  is  done 
at  right  angles  to  the  layers,  that  is,  across  the 
grain  of  the  cake.  On  the  other  hand,  when 
forming  cakes  in  the  chambers  of  the  filter- 
press,  a  segregation  of  the  ore  particles  invari- 
ably occurs,  producing  a  distorted  grain  and 
irregular  porosity.  There  is  no  way  of  remedy- 
ing such  a  defect,  because  the  cake  is  held  be- 
tween two  filter-cloths  so  as  to  necessitate  the 
use  of  a  clear  wash-liquor  that  continues  to 
pass  unevenly  through  the  cake.  With  the 
vacuum-filter  the  cake  has  a  face  in  contact 
with  the  wash-liquor,  which  is  purposely  kept 
turbid.  If  there  are  any  parts  of  uneven  flow 
in  the  cake  they  soon  choke,  causing  the  poro- 
sity to  become  adjusted  until  more  or  less  uni- 
form washing  ensues.  However,  when  deal- 
ing with  some  classes  of  ore  excellent  washing 
has  been  done  with  filter-presses,  but  my  point 
is  that  the  vacuum-filter  has  a  wider  range  of 
application  and  invariably  dilutes  the  filtrate 
less  for  equally  satisfactory  washing. 

Care  of  the  Cake. — During  the  time 
that  the  cake  is  exposed  to  the  air  it  should 
be  treated  with  care.  If  any  appreciable  suck- 
ing action  occurs,  air  is  drawn  through  the 
cake,  tending  to  disturb  its  grain  and  causing 
compacting  in  parts  and  increased  porosity 
elsewhere.  In  order  to  wash  such  a  cake  much 
liquor  is  required,  which  results  in  a  filtrate 
poor  in  metal.  This,  however,  may  be  partly 
obviated  by  using  a  highly  turbid  wash-liquor. 

If  suction  is  cut-off  the  grain  of  the  cake 
will  remain  unaltered  during  the  time  required 
for  transfer.  With  cakes  held  vertically  or 
overhanging  the  stoppage  of  the  sucking  action 
is  not  always  practicable,  because  the  small 
amount  of  moisture  always  left  behind  the 
filter-cloths  descends  by  gravity  and  should 
this  ooze  through  to  the  cake  adhesion  would 
fail,  causing  portions  of  the  cake  to  fall  away. 
One  maker  of  vacuum-filters  successfully  over- 
comes this  difficulty  by  rendering  the  lower 
margin  of  the  filter-cloth  impervious,  thus 
forming  a  trough  for  retaining  the  drained  solu- 
tion. 


OCTOBER,    1911 


287 


It  is  also  important  that  the  cake  while  ex- 
posed to  the  air  should  be  subjected  to  as  little 
vibration  as  possible.  If  this  is  violent  some 
cake  may  be  knocked  off,  but  even  a  slight 
vibration,  although  producing  no  perceptible 
effect  to  the  eye,  may  seriously  disturb  the 
grain  of  the  cake  and  spoil  its  uniform  poro- 
sity. The  risk  of  injury  from  this  cause  is 
reduced  to  a  minimum  by  using  anon-moving 
type  of  filter. 

After  the  cake  has  been  formed  and  ex- 
posed to  the  air  30  to  35%  of  its  weight  con- 
sists of  valuable  liquor,  that  is,  metallic  solu- 
tion formed  in  the  treatment-vats,  together 
with  undissolved  metallic  gold  and  silver  par- 
ticles or  compounds.  The  former  can  easily 
be  removed  fairly  well  by  means  of  a  water- 
wash,  but  if  the  latter,  which  is  usually  by  far 
the  most  valuable  of  the  two,  is  to  be  extracted, 
a  solution- wash  is  applied  before  the  water- 
wash. 

Washing  the  Cake. — This  operation  re- 
quires more  attention  than  it  usually  receives. 
After  sliming,  cyanidmg,  and  forming  the  cake, 
it  is  rarely  economical  to  hasten  the  process  at 
the  expense  of  washing.  Too  often  it  happens 
that  filters  are  so  over-loaded  with  work  as  to 
make  the  solution-washing  little  better  than  a 
farce.  There  is  no  excuse  for  this  when  we 
consider  that  the  value  of  the  metal  removed 
by  the  wash  far  exceeds  the  cost  of  the  opera- 
tion. 

The  main  object  of  the  solution-washing  is 
to  extract  on  the  filters  the  metal  that  has 
failed  to  dissolve  in  the  treatment- vats,  or  was 
re-precipitated  during  treatment,  and  inciden- 
tally to  wash  out  all  dissolved  metal  held  by 
the  cakes.  Various  independent  investigations 
have  shown  that  the  gold  and  silver  that  remain 
undissolved  in  the  treatment-vat  afteragitation 
are  partly  dissolved  while  solution- washing  the 
cake  on  the  filter.  The  undissolved  metal  is 
in  two  forms  :  that  which  is  intimately  asso- 
ciated or  combined  in  its  natural  state  with  the 
gangue,  and  that  which  after  dissolving  has 
again  returned  to  a  solid  state.  I  refer  to  this 
as  being  re-precipitated.  Both  forms  are  re- 
coverable to  an  appreciable  extent,  at  a  trifling 
cost,  after  the  cake  has  been  formed. 

Without  going  deeply  into  the  chemistry 
of  the  subject,  which  is  somewhat  obscure,  it 
is  enough  to  say  that  the  gold  and  silver  dis- 
solve on  the  filter  after  escaping  solution  in 
the  vat,  but  how  much  of  this  is  metal  m  its 
natural  state  and  how  much  is  due  to  re-pre- 
cipitation is  not  discernible.  Periodical  tests 
show  that  the  rate  of  dissolving  in  the  treat- 
ment-vat always  becomes  slower  and  slower  as 


the  operation  proceeds,  and  in  time  may  become 
so  slow  that  the  cost  of  agitating  exceeds  the 
value  of  the  metal  dissolving.  Theoretically 
the  rate  of  increase  should  be  only  in  propor- 
tion to  the  diminution  of  the  surface  of  metal 
in  contact  with  the  solution,  but  in  practice 
this  is  far  exceeded  ;  in  fact,  tests  show  that 
at  times  dissolving  appears  to  cease  altogether 
in  spite  of  metallic  particles  and  free  cyanide 
being  present.  The  phenomenon  is  explained 
by  the  solution  becoming  degraded  in  presence 
of  finely  divided  solids.  The  term  '  degraded  ' 
applies  to  a  diminution  of  the  solvent  power 
of  the  solution  due  to  the  introduction,  from 
the  ore,  of  soluble  impurities  having  a  reduc- 
ing action.  If  it  were  made  possible  to  bring 
fresh  potent  solution  continuously  in  contact 
with  the  ore  particles,  instead  of  simply  circu- 
lating the  degraded  solution,  the  rate  of  dis- 
solving would  be  kept  more  constant  and  the 
tendency  to  re-precipitate  would  be  mini- 
mized. 

The  vacuum-filter  provides  means  for  per- 
forming this  operation  almost  ideally.  The 
cake  is  submerged  in  a  potent  wash-solution 
which  is  slowly  drawn  through  the  pores  and 
in  its  course  dissolves  a  portion  of  the  gold 
and  silver  together  with  degrading  matter,  as 
in  the  treatment-vat,  but  as  the  solution  be- 
comes degraded  it  is  drawn  forward  out  of  the 
region  of  the  gold  and  silver  particles  and  is 
replaced  with  fresh  potent  solution,  the  action 
being  continuous.  In  this  way  the  rate  of  dis- 
solving of  the  gold  and  silver,  per  unit-area 
exposed  to  the  solution,  remains  constant.  The 
rate  lessens  proportionately  only  as  the  area 
of  the  exposed  metal  diminishes. 

The  foregoing  applies  with  even  greater 
force  when  a  compound,  such  as  silver  sul- 
phide, is  also  present.  Silver  sulphide,  al- 
though only  sparingly  soluble,  readily  degrades 
a  solution,  whereby  it  stops  or  hinders  the 
dissolving  of  any  metallic  gold  and  silver,  as 
well  as  further  silver  sulphide  that  may  be 
present  in  the  pulp.  Various  devices  are  em- 
ployed for  reviving  this  lost  dissolving  power 
in  order  that  the  solution  may  be  enriched  be- 
fore filtering,  and  even  when  they  are  effective 
the  dissolved  metal  is  often  in  such  an  unstable 
condition  that  some  of  it  re-precipitates  either 
in  the  vat  or  in  the  cake.  The  solution-wash, 
if  properly  applied,  practically  removes  the 
whole  of  this  re-precipitated  metal,  together 
with  native  metal  that  had  hitherto  escaped 
solution. 

Re-precipitation  and  Re-solution. — 
It  has  often  been  observed  that  a  maximum 
extraction  in  the  agitator- vat  is  followed  by 


288 


THE    MINING    MAGAZINE 


re-precipitation  of  the  gold  and  silver.      What 
is  not  so  easily  observed  and  not  so  well  known 
is  that  precipitation  and  dissolution  proceed  in 
the  vat  at  the  same  time,  and  for  this  reason 
among  others  the  gold  and  silver  in  the  pulp 
are  never  completely   brought  into  solution. 
It  is  also  not  realized  that  this  re-precipitated 
metal  does  not  re-dissolve  in  the  same  solution 
although  the  native  metal  may  continue  dis- 
solving slowly  in  its  normal  manner.     With- 
out going  into  the  subject  deeper,  we  may  say 
that  re-precipitation  is  due  to  local  action  of 
both  a  physical  and  chemical  nature.     Gra- 
phite, tellurides,   sulphides,   arsenides,   char- 
coal, grease,  oils,  and  even  silica  or  alumina 
in  an  extremely  fine  state  of  division,  precipi- 
tate both  gold  and  silver  from  working  cyanide 
solutions,  and  this  precipitate  shows  little  or 
no  tendency  to  re-dissolve  in  the  same  solu- 
tion.    If  this  re-precipitated  metal  be  filtered 
oflf,  washed,  and  re-pulped  with  a  fresh  solu- 
tion, a  portion  re-dissolves  and  if  the  operation 
be  repeated  a  further  portion  re-dissolves.   In 
time  nearly  the  whole  of  the  metal  may  in  this 
way  be  re-dissolved.     Such  a  process  could 
not,  of  course,  be  employed  economically,  but 
the  vacuum-filter  makes  it  possible  to  apply 
similar  fresh  solutions  continuously  and  with- 
out the  necessity  of  re-pulping.     Thus  when 
a  fresh  potent  solution  is  drawn  steadily  and 
evenly  through  the  cake  the  metallic  particles, 
being  continuously  surrounded  by  the  advanc- 
ing liquor,  re-dissolve  and  pass  away  with  the 
filtrate.  This  re-dissolving  isnot  instantaneous 
but  requires  time  for  contact ;  hence  a  rapid 
flow  through  the  cake  does  not  hasten  matters, 
but  results  only  in  a  large  volume  of  filtrate 
poor  in  metal.     A  cake  i  in.  thick  requires 
about  as  much  time  to  be  solution-washed  as 
one  2  in.  thick. 

Silver  is  much  more  prone  to  re-precipita- 
tion than  gold,  and  is  afterward  more  slowly 
re-dissolved  on  the  filter.  Even  the  addition 
of  water  to  the  pulp  is  sufficient,  in  some  in- 
stances, to  cause  an  appreciable  proportion  of 
the  silver  to  assume  a  solid  state. 

It  often  happens  that  scum  or  froth  accumu- 
lates on  the  surface  of  the  pulp  in  the  agitator- 
vats.  This  sometimes  becomes  extremely  rich 
in  gold  and  silver,  a  large  proportion  of  which 
may  be  directly  traced  to  re  -  precipitation. 
The  enrichment  of  the  scum  is  evidence  of 
re-precipitation  occurring  in  the  mass  of  agi- 
tated slime.  It  is  difficult  to  bring  the  solid 
particles  of  the  scum  in  contact  with  a  solution 
in  the  treatment-vats,  but  if  it  be  transferred 
periodically  to  the  filter,  along  with  some  slime, 
it  may  be  solidified  with  a  little  trouble  into  a 


cake,  and  freed  of  metal  with  a  suitable  wash- 
solution. 

Preparation  and  Application  of  the 
Wash   Solution.  —  This  is   usually  made 
from  the  barren  solution  that  leaves  the  zinc- 
box.     Before  being  used  it  should  be  thor- 
oughly aerated  to  ensure  complete  oxidation 
of  any  reducing  matter  present.   If  the  wash- 
solution  is  not  already  muddy  it  is  advisable 
to  add  a  little  of  the  finest  slime,  the  object 
being  to  provide  means  for  readjustment  of 
any  slightly  uneven  permeability  in  the  cake, 
such  as  might  accidentally  have  occurred  dur- 
ing the  time  that  the  cake  is  exposed  to  the 
air.     The  solution  just  before  use  should  be 
made  stronger  in  cyanide  than  that  originally 
used    in    the    treatment  -  vats.      How   much 
stronger  is  found  by  trial,  and  if  silver  sul- 
phide  be   present   the  strength   of   the  wash 
requires  special  attention.      It  is  generally  in- 
advisable to  add  free  alkali  to  wash-solutions. 
The  object  of  applying  this  wash  is  to  im- 
poverish the  cake  with  a  minimum  quantity 
of  solution  in  a  minimum  time  and  obtain  a 
filtrate  as  rich  as  possible  in  gold  and  silver. 
As  already  stated  there  is  nothing  to  be  gained 
by  rushing  the  solution  through  the  cake  at  a 
high  velocity.     It  is  only  necessary  to  give  it 
such  a  rate  of  flow  as  would  prevent  backward 
diffusion,  and  if  this  were  maintained  the  cake 
would  be  washed  with  a  minimum  quantity  of 
solution  and  produce  a  filtrate  of  maximum 
richness.      In  practice,  however,  this  slow  rate 
of  flow  cannot  be  employed  because  it  is  neces- 
sary to  accomplish  the  washing  in  a  limited 
time,  even  though  the  filtrate  should  suffer  in 
richness.     The  time  allowed  by  operators  to 
solution-wash  the  cakes  is  as  a  rule  absurdly 
short,  with  the  consequence  that  great  loss  in 
the  aggregate  occurs.     In  every  case  when 
applying  a  solution-wash  the  vacuum  should 
be    kept   as    low    as    possible    for    the    time 
allowed. 

After  completing  the  solution-washing  the 
cake  contains  cyanide  and  should  carry  only 
a  minute  quantity  of  dissolved  gold  and  silver, 
chiefiy  obtained  from  the  barren  solution.  It 
is  generally  economical  to  save  the  cyanide  by 
applying  a  water- wash. 

Water-Wash.  —  One-third  of  a  ton  of 
wash-solution  for  every  ton  of  ore  is  retained 
by  the  cake.  If  therefore  this  solution  con- 
tains 3  lb.  of  cyanide  per  ton  the  solution  in 
the  cake  will  contain  i  lb.  per  ton  of  solid. 
The  object  of  the  water-wash  is  to  remove 
this  half-pound  of  cyanide,  or  a  large  propor- 
tion of  it  for  further  use,  without  unduly 
diluting  the  filtrate,  and  incidentally  any  dis- 


OCTOBER,    1911 


289 


solved  metal  present.  Theoretically  this  would 
appear  to  be  a  comparatively  simple  matter, 
for  it  may  be  argued  that  it  is  necessary  to  draw 
intothecake  only  one-thirdof  its  weightin  water 
and  thus  pushforwardand  displace  the  retained 
solution.  In  ordinary  practice,  however,  it  is 
found  that  when  only  this  amount  of  water  is 
used  less  than  half  the  cyanide  and  metallic 
contents  is  removed.  The  difficulty  is  to 
recover  an  appreciable  amount  of  the  remain- 
der without  undue  dilution  of  the  stock  solu- 
tion. The  curve  m  Fig.  2  shows  graphically 
the  diluting  of  the  filtrate  as  the  water- 
wash  is  drawn  through  the  cake,  the  vacuum 
being  at  a  maximum  and  constant.  It  will  be 
noticed  that  the  first  40%  of  the  filtrate  was 


most  efficient  wash  consistent  with  a  given 
strength  of  filtrate,  except  by  trial. 

Washing  by  Filtration  and  Decan- 
TATION.  — •  The  simplest  of  all  methods  of 
washing  is  by  decantation.  In  practice,  how- 
ever, it  presents  serious  objections,  not  the 
least  of  which  is  the  unavoidable  loss  due  to 
dissolved  metal  remaining  associated  with  the 
residue  discharged  after  the  final  decantation. 
One  example  on  gold  ore  will  suffice  as  an 
illustration.  Assuming  that  the  total  solution 
in  use  is  7  tons  to  1  ton  of  ore,  the  number 
of  decantations  is  three  and  the  residue  pulp 
contains  50%  moisture.  The  losses  then  for 
various  assay-values  of  original  solution  are 
given   in   the   following  table,    (l)    when  the 


(1)  Added  liquor  free  from  metal. 


Dissolved  gold  before 

first  decantation  per 

ton  of  solution. 


(2)  Added  liquor  containing  metal. 


Loss  of  fiold  in  residue 
solution  per  ton. 


Loss  of  gold  in  pence  per  ton  due 
to  added  liquor  containing  per  ton 


Total  loss  of  gold  in  residue  solution 

in  pence  per  ton  when  added  liquor 

contains  per  ton 


Dwt. 



Pence 

2gr. 

3  gr. 

4  gr. 

2gr. 

3gr. 

4gr. 

0"5 

0"94 

4i 

64 

84 

1 
2 

1-88 
376 

376 

5'65 

7"53 

54 
74 

74 
94 

94 

11 

3 

5"65 

94 

11 

13 

only  sHghtly  diluted  (2  lb.  to  17  lb.)    The  next 
15%  caused  a  dilution  from  17  to  0'5  lb.  per 
ton.     After  this  the  dilution  became  less  rapid 
and  the  removal  of  the  cyanide  from  the  cake 
wascomparatively  slow.  A  low  vacuumthrough- 
out  the  operation  is  desirable  for  a  maximum 
strength  of  filtrate,  but  the  curve  would  indi- 
cate that  a  high  vacuum  at  the  start  would 
save  time  if  maintained  no  longer  than  is  just 
necessary  to  withdraw  the  stronger  portion  of 
the  filtrate,  and  then  if  a  low  vacuum  be  ap- 
plied the  greater  part  of  the  remaining  cyanide, 
being  held  by  adsorption",  and  requiring  time 
of   contact   to  diffuse  into   the   added   water, 
would  produce   a   filtrate  sufficiently   strong 
not   inconveniently  to  dilute  the  stock  solu- 
tion.    The  extent  to  which  the  vacuum  should 
be  lowered  depends  on   the   porosity  of   the 
cake,  and  the  length  of  time  that  the  wash  is 
applied  depends  on  the  fineness  of  the  slime. 
The  more  porous  the  cake,  the  lower  should 
be  the  vacuum  ;  and  the  finer  and  more  amor- 
phous the  slime,  the  longer  should  be  the  time 
of  contact.     There  is  no  way  of  determining 
with  accuracy  the  quantity  of  water  giving  the 

* '  Adsorption  '  refers  to  a  surface  condensation  whereby  the 
dissolved  metal  and  cyanide  are  held  in  a  concentrated  form  at 
the  surfaces  of  slime-particles.  The  condition  increases  with 
the  fineness  of  the  slime. 


added  liquor  is  free  from  dissolved  metal  and 
(2)  when,  as  is  usual,  the  added  liquor  contains 
a  small  quantity  of  dissolved  metal. 

These  are  theoretical  losses,  on  the  assump- 
tion that  the  moisture  after  each  decantation 
is  reduced  to  50%.  In  practice,  it  is  often 
difficult  to  maintain  a  residual  moisture  so 
low,  especially  in  cold  weather,  owing  to  the 
slowness  of  settling  and  the  necessity  for  keep- 
ing the  capacity  of  the  plant  abreast  of  the 
mill.  Thus  if  the  residual  pulp  contained  60% 
moisture,  instead  of  50%,  the  total  loss  would 
be  increased  by  8%.  When  weallowforlossdue 
to  adsorption  which  in  practice  always  occurs, 
the  above  figures  may  be  greatly  increased. 

In  filtering,  unfortunately,  there  is  no  simple 
way  of  calculating  the  theoretical  loss  after 
washing,  for  comparison  with  decantation, 
owing  to  a  number  of  uncertain  factors.  The 
amount  of  dissolved  metal  left  in  a  cake  has 
no  relation  to  the  richness  of  the  original  solu- 
tion. Thus  if  a  cake  be  washed  with  its  own 
weight  of  water  it  matters  not  whether  it  con- 
tained 4  dwt.  or  3  dwt.  per  ton  of  solution  ; 
the  loss  in  the  residue  solution  would  be  much 
about  the  same.  In  decanting  the  metal  con- 
tents are  removed  by  two  to  four  washes  or 
dilutions,  while  in  filtering  it  is  done  by  an 


290 


THE    MINING    MAGAZINE 


infinite  number  of  washes.  It  may  be  proved 
mathematically  that  the  greater  the  number  of 
washes  with  a  given  quantity  of  water,  the 
more  perfect  is  the  wash.  This  may  be  for- 
cibly illustrated  by  an  example  :  If  the  total 
quantity  of  liquor  in  use  in  the  decantation  pro- 
cess be  made  the  same  as  in  the  filter  process, 
say  3:1,  the  theoretical  separation  of  dissolved 
metal  by  three  decantations  would  be  only 
78'4%.  In  practice  75%  would  be  considered 
fair  work.  In  the  filtration  process,  with  this 
same  proportion  of  liquor,  there  is  no  diffi- 
culty in  separating  99%  of  the  dissolved  metal. 
Again,  in  order  to  get  99%  of  dissolved  metal 
separated  by  three  decantations  it  would  re- 
quire a  total  of  12  tons  of  liquor  to  1  ton  of 
solid.  These  figures  are  based  on  the  assump- 
tion that  the  added  wash-liquor  contains  no 
dissolved  metal. 

In  practice  the  wash-waters  generally  con- 
tain small  quantities  of  dissolved  metal,  and 
the  solution  in  the  residue-pulp  contains  this 
metal  in  proportion  to  the  amount  of  moisture 
retained,  which  for  filtration  is  approximately 
1  of  solution  to  2  of  solid  and  for  decantation 
1:1.  The  loss  of  metal  from  this  cause  is 
therefore  twice  as  much  for  decantation  as  for 
filtration.  Then  again  the  wide  difference  in 
the  amount  of  wash  liquor  required  in  filtra- 
tion and  decantation  processes  affects  the  cost 
per  ton  of  ore,  in  the  subsequent  treatment  of 
the  solution  to  recover  the  gold  and  silver.  In 
filtration  the  amount  of  wash-liquor  used  sel- 
dom exceeds  twice  the  weight  of  the  solid,  and 
with  care  may  be  considerably  less  without 
increasing  the  unavoidable  loss  of  metal.  On 
the  other  hand,  with  the  decantation  process 
five  of  wash-liquor  to  one  of  solid  is  common 
practice,  and  this  cannot  be  economically  re- 
duced without  increasing  the  loss  of  metal. 

Another  feature  for  comparison  between 
washing  by  the  two  systems  is  the  loss  due 
to  re-precipitation  and  adsorption.  The  de- 
cantation process  necessarily  involves  a  suc- 
cessive dilution  of  the  solution,  on  account  of 
the  large  volumes  in  use  and  to  prevent  ex- 
cessive loss  of  cyanide  in  the  residue. 

Dilution  of  the  liquor  containing  dissolved 
metal,  in  presence  of  finely  divided  solid  par- 
ticles in  suspension,  invariably  results  in  loss 
of  dissolved  metal,  whether  it  be  by  re-pre- 
cipitation or  by  adsorption.  The  extent  to 
which  these  phenomena  develop  depends  on 
the  constituents  of  the  pulp  and  the  fineness 
of  the  ore  particles.  Silica,  which  is  generally 
present  in  a  gelatinous  or  colloidal  condition, 
has  the  property  of  carrying  down  an  appre- 
ciable amount  of  gold  and  silver  and  cyanide 


by  merely  diluting  the  solution  with  water. 
Hydrated  alumina  possesses  this  property  to 
an  extraordinary  degree.  There  is  no  doubt 
that  much  of  the  loss  in  residue  from  the  de- 
cantation process  is  due  to  adsorption  and  re- 
precipitation,  caused  by  dilution  in  the  wash- 
ing stages. 

These  phenomena  also  take  place  in  the 
filtration  process,  but  since  the  solution  need 
not  be  diluted  until  the  dissolved  metal  has 
been  removed  from  the  cake  by  the  solution- 
wash  the  loss  of  gold  and  silver  by  adsorp- 
tion is  minimized.  The  loss  due  to  the  dilu- 
tion that  occurs  in  the  water-wash  is  chiefly 
in  cyanide.  Again,  re-precipitated  metal  is 
re-dissolved  in  passing  the  strong  wash-solu- 
tion through  the  cake  whereas  the  weaker  so- 
lution added  in  decantation,  although  potent 
on  natural  metallic  particles,  has  but  little 
effect  in  re-dissolving  the  re-precipitated  metal. 

Glaciation. — On  Advent  bay,  in  Spitzber- 
gen,  a  coal  entry  has  been  driven  2025  ft.  into 
a  hill  and  at  the  face  the  height  to  surface  is 
800  ft.  Yet  the  rock  is  completely  frozen  all 
the  way,  despite  the  circulation  of  air  from  the 
surface  by  means  of  a  fan.  These  were  the 
conditions  as  observed  in  July,  1911.  Here 
we  have  an  illustration  of  the  penetration  of 
cold  during  a  Glacial  period,  that  is,  of  per- 
manent frost  able  to  withstand  the  seasonal 
thaw  at  the  surface. 

Production  of  Zinc. — Figures  for  the  me- 
tallic content  of  zinc  ores  produced  in  various 
countries  show  that  Germany  heads  the  list 
with  230,203  tons,  and  is  followed  by  the 
United  States  with  208,859  tons  and  Australia 
with  146,348  tons.  The  next  largest  produ- 
cers are  Spain  with  69,920  tons,  Italy  with 
42,828  tons,  Algeria  with  29,652  tons,  and 
Sweden  with  28,900  tons.  The  total  produc- 
tion of  the  world  was  855,992  tons. 

In  the  Dutch  East  Indies  by  far  the 
most  important  of  the  six  gold  mines  is  the 
Redjang  Lebong,  Sumatra;  during  1910  the 
value  of  the  output  was  ^403,000  and  the 
dividend  was  at  the  rate  of  100%.  The  next 
largest  is  the  Ketahoen,  also  in  Sumatra  ;  the 
output  was  worth  ;^1 14,000  and  the  dividend 
was  20%.  There  are  two  producers  in  Cele- 
bes, the  Totok  and  Paleleh,  yielding  ;^63,500 
and  ;^58,500  during  1910  respectively;  the 
latter  paid  1\%  dividend.  The  Sintoeroe  in 
West  Borneo  produced  ^17,500  and  made  a 
small  profit.  The  returns  for  the  Simau  in 
Sumatra  are  not  complete,  but  during  the  first 
nine  months  of  1910  the  output  was  worth 
i'40,800. 


THE  OIL   INDUSTRY  OF  CALIFORNIA 

By  WILLIAM  FORSTNER. 


THE  daily  averages  of  production  given 
in  Tables  L  and  IL  show  conclusively 
that  there  is  no  increase  of  oil  production 
in  the  State  of  California.  Comparing  the 
figures  for  the  months  of  July  1910  and  June 
1911,  there  is  a  decrease  in  average  daily  pro- 
duction of  19,409  bbl.,  or  8i%.    The  consump- 


July  31,  1910.  This  amount  of  stock  on  hand 
represents,  at  the  rate  of  consumption  of  the 
month  of  June  1911,  the  consumption  of  six 
months,  and  is  notexcessive.  Thestoringof  the 
oil  is,  however,  costly  and  has  been  especially 
a  heavy  burden  for  the  Independent  Producers 
Agency,  largely  composed  of  small  operators. 


tion  has,  however,  increased  ;  again  comparing 
the  same  months  there  is  an  increase  in  aver- 
age daily  consumption  of  18,032  bbl.,  or  10'8%. 
Consequently  the  daily  surplus  of  production 
over  consumption  has  decreased  50'9%. 

The  stock  on  hand  on  June  30,  1911,  was 
36,184,788  bbl.,  an  increase  of  9,758,819  over 


The  Agency  has  at  present  to  care  for  over 
4,000,000  bbl.  in  storage  and  this  expense  has 
been  the  cause  of  much  dissatisfaction.  The 
cry  about  over-production  is  largely  due  to  the 
complaints  of  these  small  operators,  who  have 
not  the  capital  required  to  operate  without  im- 
mediate returns.  The  Agency  is  now  perfect- 


291 


292 


THE    MINING    MAGAZINE 


ing  its  plans  to  take  care,  at  a  minimum  cost, 
of  its  present  surplus  and  of  that  which  it  pre- 
sumably will  accumulate  in  the  future,  so  that 
this  difficulty  can  be  considered  obviated.  The 
Associated  Oil  and  theStandardOilcompanies, 
the  two  large  marketers  in  California  are  also 
increasing  their  storage  facilities,  so  that  the 
surplus  oil  will  receive  proper  care. 

The  principal  market  for  California  oil  has 
been  in  the  States  along  the  Pacific  coast, 
western  Nevada,  Arizona,  and  a  part  of  north- 
ern Mexico.  In  the  Puget  sound  region  this 
oil  may  in  the  future  have  to  meet  the  com- 
petition of  the  Katalla  oilfield,  Alaska,  which 
is  entering  the  stage  of  production.  Nothing 
has  as  yet  developed  in  the  Alberta  field, 
British  Columbia,  to  justify  any  expectation 
of  a  production  of  commercial  importance. 

The  price  paid  for  fuel-oil  at  the  wells  has 
fluctuated  little  during  the  last  few  months. 
From  October  1910  to  June  1911,  the  Agency 
has  paid  to  its  members  35  cents  per  barrel  for 
each  month's  product.  The  Standard  Oil  has 
cut  the  price  of  fuel-oil  (heavier  than  22"^  B)  to 
30  c.  per  bbl.  in  April  and  is  still  making  con- 
tracts at  that  figure.  Whether  this  price  will 
be  upheld  depends  upon  the  future  relation  of 
consumption  and  production. 

As  to  consumption,  this  can  only  be  in- 
creased by  generalizing  the  use  of  fuel-oil,  and 
depends  on  the  extent  of  territory  wherein  the 
oil  can  advantageously  replace  coal  for  all  pur- 
poses that  do  not  require  coal  as  special  fuel, 
and  compete  with  oil  from  other  sources.  The 
radius  of  territory  which  a  certain  field  can 
control  therefore  depends  on  whether  the  price 
at  which  the  oil  can  be  laid  down  at  the  dis- 
tributing points,  makes  that  oil  the  preferable 
and  most  economic  fuel.  It  is  generally  as 
sumed  in  California  that  with  the  opening  of 
the  Panama  Canal  this  radius  will  be  extended. 
Water  transport  through  the  Canal,  will,  how- 
ever, also  extend  the  radius  of  control  of  the 
Texas,  Oklahoma,  and  Mexican  oilfields  ;  and 
where  the  boundaries  of  these  respective  terri- 
tories will  come  has  yet  to  be  determined. 
These  fields  can  hardly  compete  on  the  Pacific 
with  California,  and  the  increased  maritime 
movement  on  the  Pacific  Ocean  will  certainly 
offer  an  enlarged  outlet  for  California  fuel-oil. 

To  introduce  oil  as  fuel  in  new  territories  of 
consumption,  and  to  induce  consumers  to  adopt 
its  use,  it  IS  necessary  to  assure  them  a  con- 
stant supply  at  a  reasonable  figure,  and  there- 
fore the  two  causes  of  complaint  of  the  opera- 
tors, large  surplus  and  relatively  low  price, 
tend  to  the  future  benefit  of  the  oil  business  in 
California,  creating  a  market  and  extending  its 


territory.  Table  IV.,  giving  the  exports  from 
San  Francisco,  shows  what  a  relatively  small 
portion  of  the  output  of  California  is  exported, 
both  as  crude  oil  and  as  petroleum  products  ; 
also  a  gradual  increase  will  be  noted. 

As  to  production,  unless  an  unexpected  num- 
ber of  new  wells  of  phenomenal  importance 
come  in  within  the  near  future,  it  is  reason- 
able to  expect  that  the  production  will  remain 
about  at  the  present  figure.  The  yield  of 
new  wells,  in  the  regular  course  of  develop- 
ment, will  be  counterbalanced  by  the  decrease 
in  production  of  the  older  wells.  The  produc- 
tion of  natural  gas  in  the  Buena  Vista  hills, 
east  of  Midway,  is  assuming  such  proportions 
that  this  product  may  become  an  important 
factor.  The  natural-gas  belt  has  been  proved 
over  a  distance  of  12  miles,  with  a  width  of 
at  least  one  mile.  The  wells  are  large  pro- 
ducers, with  very  heavy  pressure.  The  natural 
gas  is  used  as  fuel  in  the  Midway  field  and  is 
piped  to  Bakersfield  for  domestic  and  other 
purposes.  If  it  can  be  proved  that  the  charac- 
ter of  this  natural-gas  field  guarantees  a  con- 
siderable length  of  life  for  the  supply,  there 
is  no  doubt  that  it  will  be  piped  to  Los  Angeles 
and  to  San  Francisco,  as  even  the  present  out- 
put, estimated  at  230,000,000  cubic  feet  per 
day,  would  be  sufficient  to  provide  the  amount 
required  in  those  cities  :  but  the  experience  in 
the  Eastern  and  Middle  West  gas-fields,  where 
the  supply  diminished  rapidly,  has  rendered 
manufacturers  cautious  in  adopting  this  fuel, 
notwithstanding  its  great  advantages.  When 
the  permanency  of  the  supply  is  demonstrated, 
this  product  will  certainly  in  many  instances 
displace  oil  as  fuel. 

The  price  paid  for  fuel-oil  at  the  wells  has 
fluctuated  only  slightly  during  recent  months  ; 
from  October  1910  to  June  1911,  the  Agency 
has  paid  its  members  35  c.  per  bbl.  for  each 
month's  product. 

As  to  refining  oil,  the  difference  in  pro- 
duction between  the  lowest  month,  November 
1910,  and  the  month  of  June  1911,  see  Table 
I.,  is  370,889  bbl.  From  Table  II.  it  will  be 
seen  that  the  difference  in  production  between 
these  two  months  for  the  San  Joaquin  valley 
group,  392,118  bbl.,  is  greater  than  the  total 
difference.  The  increase  in  production  of  the 
Midway  field  for  the  same  month  was  650,555 
bbl.  This  field  produces  both  refining  and  fuel- 
oil.  It  is  impossible  for  anyone  outside  of  the 
marketing  companies  to  obtain  exact  figures 
of  the  shipments  made  by  the  different  pro- 
ducers, but  I  believe  I  am  not  far  from  the 
actual  facts  when  stating  that  at  least  one  half 
of  this  increased  production  was  refining  oil. 


OCTOBER,    1911 


293 


Table  I. 

Production  and  consumption  year  ended  June  30, 

1911. 

Total  number  of  Average  Daily 

'""^                         Barrels  produced  Production          Consumption* 

July    7,207,890  232,545          178,803 

August  7,368,320  237,689          178,391 

September 6,858,025  228,601           177,438 

October 6,552,281  211,364          184,032 

November 6,323,189  210,773          190,490 

December 6,603,496  213,016          192,553 

1911 

January 6,566,180  211,812    179,934 

February 5,973,206  213,329    184,365 

March  7,089,955  228,708    164,1 15f 

April  6,929,337  230,938    203,170 

May  7,113,466  229,467    207,553 

June  6,694,078  223,136    196,835 

*Consumption  is  the  actual  amount  of  oil  moved  from  the  fields. 
tThis  abnormally  low  figure  is  due  to  breakage  in  the  pipe-lines  caused 
by  heavy  storms. 


Table  III. — Stocks 

Oil  at  terminals  and  in  hands  of 
marketers  and  producers. 


1910 


Bbl. 


July 

31 

26,425,969 

August 

30 

28,264,169 

September 

30 

29,799,068 

October 

31 

30,646,429 

November 

30 

December 

31 

32,500,000 

1911 

January 

31 

32,800,000 

February 

28 

33,588,000 

March 

31 

April 

30 

36,525,096 

May 

31 

'■" 

June 

30 

36,184,788 

*Dat 

a  not  available. 

Table 
Monthly  and  average  daily  production  per 

1910  San  Joaquin  Valley 

Month  Daily 

July--- 5,582,564  180,083 

August 5,591,939  186,378 

September 5,335,182  177,839 

October 4,995,677  161,151 

November  4,817,615  160,587 

December  5,103,748  164,637 

1911 

January  5,109,734  164,830 

February 4,582,676  163,667 

March 5,472,527  176,533 

April  5,248,237  174,941 

May  5,361,356  172,970 

June  5,209,733  173,658 


II. 


roup  for 

year  ended  Ji 

ane  30,  1911. 

Coast  Group 

Southern  Group 

Month 

Daily 

Month 

Daily 

727,970 

23,483 

918,255 

29,621 

855,520 

28,517 

920,862 

30,695 

625,900 

20,863 

896,946 

29,898 

630,610 

20,342 

925,994 

29,871 

623,850 

20,795 

881,724 

29,391 

643,370 

20,754 

856,378 

27,625 

621,770 

20,057 

837,676 

23,796 

625,247 

22,330 

765,283 

27,331 

765,131 

24,682 

852,279 

27,493 

793,520 

26,451 

887,580 

29,586 

764,961 

24,676 

987,149 

31,845 

503,420 

16,781 

980,926 

31,697 

Table    IV. 
Export  of  Petroleum  and  its  products  from  San  Francisco  for  the  years  ended 

June  30,  1909,  1910,  and  1911. 

Crude  oil  (gal.) 23,289,280                 58,558,689  ^5,029,876 

Naphtha                                       62,219                       126,651  115,194 

Illuminating  oil  (gal.) 68,832,363                  38,746,450  ^^'IfHno 

Lubricating  oil      „         433,547                      490,114  568,799 

Residuum               ,,         48,051                 34^  4,663,373 

Total  (gal.) 92,665,460                  97,956,332  109,809,041 


k 


294 


THE    MINING    MAGAZINE 


The  Standard  Oil  Co.  is  the  only  purchaser 
of  refining  oil  in  the  San  Joaquin  valley.  The 
total  amount  of  oil  used  for  refinery  purposes, 
as  far  as  I  can  learn,  is  400,000  bbl.  per  month, 
including  that  used  in  the  manufacture  of  as- 
phalt. From  the  Midway  field  alone,  the  Stan- 
dard Oil  runs  at  present  over  500,000  bbl.  of 
light  oil,  and  consequently  the  price  paid  for 
that  oil  has  lately  fallen  from  65  to  45  cents 
per  barrel.  For  the  same  grade  of  oil  70  c.  and 
more  is  paid  in  the  southern  field,  where  there 
is  more  competition  for  that  product.  The 
Guaranty  Pipe  Line  Co.  is  constructing  a  pipe- 
line from  the  South  Midway  field  to  the  coast, 
with  a  branch  to  Los  Angeles.  This  pipe-line 
will  offer  a  new  outlet  for  the  light  oils  of  the 
Midway  field  to  the  refineries  in  the  southern 
part  of  the  State.  The  Dutch-Shell  people 
have  petitioned  for  a  site  to  erect  a  refinery 
at  Martinez,  on  the  upper  part  of  San  Fran- 
cisco bay,  which  may  offer  in  the  near  future 
another  outlet  for  the  Midway  refinery  oil. 

Outside  of  the  oil  used  by  the  Southern 
Pacific  and  the  Santa  Fe  railroads,  nearly  all 
the  oil  produced  in  California  is  marketed  by 
the  Standard  Oil  Co.,  the  Union  Oil  Co.,  or 
the  Associated  Oil  Company.  The  Standard 
produces  far  less  oil  than  it  uses  and  markets. 
This  company  is  therefore  a  buyer  on  a  large 
scale,  and  hence  it  is  to  its  interest  to  depress 
thepriceof  the  oil  as  much  as  possible.  It  is  the 
greatest  refiner  on  the  coast,  and  the  principal 
buyer  of  refining  oil.  In  the  San  Joaquin 
valley  this  company  is  practically  the  only 
buyer  of  that  grade  of  oil  because  the  other 
pipe-lines  from  that  field  to  the  distributing 
points  are  used  for  fuel-oil,  and  therefore  it 
may  succeed  in  keeping  the  price  of  refining 
oil  down  for  a  certain  length  of  time. 

The  Standard  Oil  Co.  is  giving  several  signs 
of  intending  to  increase  its  activity  in  the  Cali- 
fornia field.  It  is  doubling  the  capacity  of  its 
pipe-line  from  the  San  Joaquin  valley  to  its 
refinery  at  Point  Richmond  on  the  bay  of  San 
Francisco,  and  also  materially  increasing  its 
storage  facilities  in  the  Kern  River  field.  It 
is  further  reported  that  this  company  intends 
to  erect  a  large  tank- farm  for  the  storage  of 
oil  at  Los  Nietos,  three  miles  from  Whittier, 
in  Los  Angeles  county,  and  has  acquired  a  con- 
siderable ocean  frontage  west  of  Los  Angeles, 
where  it  is  erecting  a  large  refinery  plant. 

The  Union  Oil  Co.  markets,  besides  its  own 
product,  that  of  the  Independent  Producers 
Agency.  The  latter  has  a  pipe-line  system 
connecting  the  San  Joaquin  valley  with  Avila, 
on  the  coast  in  San  Luis  Obispo  county.  The 
Union  has  several  pipe-lines  connecting  the 


Santa  Maria  fields,  the  Ventura  county  fields, 
and  the  Southern  California  fields  with  the 
coast.  This  company  has  a  large  fleet  of  tank- 
vessels  and  barges. 

The  Associated  Oil  Co.  has  entered  into  a 
contract  with  the  Union  Oil  Co.  and  the  In- 
dependent Producers  Agency  to  market  their 
surplus  oil,  existing  business  and  the  renewal 
thereof  to  remain  with  the  Union,  as  also  the 
exclusive  right  to  make  sales  on  the  west  coast 
of  America.  The  Associated  Oil  has  a  pipe- 
line from  the  Kern  River  field  to  Port  Costa, 
and  one  from  Maricopa,  through  Midway, 
McKittrick,  and  Coalinga,  to  Port  Costa  ;  also 
another  from  Coalinga  to  the  bay  of  Monterey. 
Further  it  has  a  pipe-line  from  the  Santa  Maria 
field  to  its  refinery  at  Gaviota,  in  Santa  Bar- 
bara county,  and  one  from  the  Salt  Lake  field 
to  Los  Angeles. 

The  Independent  Producers  Agency  is  a 
combination  of  nearly  all  the  producers  in 
the  San  Joaquin  valley  outside  of  the  above 
named  companies,  the  Southern  Pacific  Rail- 
road (Kern  Trading  &  Oil  Co.),  the  Santa  Fe 
Railroad  (Petroleum  Development  Co.),  and 
a  very  few  of  the  largest  producers. 

It  is  clearly  to  the  interest  of  the  Union  Oil 
Co.,  the  iVssociated  Oil  Co.,  and  the  Indepen- 
dent Producers  Agency  to  maintain  the  price 
of  oil.  As  to  the  railroads,  both  the  Southern 
Pacific  and  the  Santa  Fe  are  endeavouring  to 
have  their  production  equal  their  consumption, 
and  as  it  is  of  the  greatest  importance  for  them 
to  have  a  permanent  supply  for  the  longest 
possible  time,  it  is  improbable  that  they  will 
produce  more  than  required  for  their  own  con- 
sumption, and  hence  the  price  of  oil  is  a  matter 
of  little  concern  to  them. 

The    World's    Coal    Resources.  —  The 

twelfth  International  Geological  Congress  is  to 
be  held  m  Toronto  during  the  summer  of  1912, 
and  the  attention  of  members  is  to  be  concen- 
trated on  a  study  of  the  world's  resources 
of  coal.  Circulars  have  been  despatched  in- 
viting assistance  in  the  compilation  of  records 
of  deposits  both  worked  and  unworked,  and 
already  the  preparation  of  reports  of  the  re- 
sources of  every  country  has  been  taken  in 
hand.  It  will  be  remembered  that  last  year 
the  iron  resources  were  thoroughly  discussed 
at  the  Stockholm  Congress,  and  the  literature 
then  collected  has  been  published  in  monu- 
mental volumes.  At  the  time  it  was  admitted 
that  the  consideration  of  the  iron  resources 
was  incomplete  without  full  information  about 
fuel,  and  it  was  felt  that  coal  demanded  similar 
treatment. 


WATER-BORNE  PACKING  FOR  STOPE-FILLING 


By  EDGAR  PAM. 


THIS  process,  commonly  known  as  '  sand- 
filling,'  was  started  in  Silesia  in  1901,  and 
its  value  has  been  proved  by  the  rapidity 
with  which  it  has  been  introduced  all  over  the 
mining  world. 

The  purpose  is  the  strengthening  of  the  mine 
workings,  the  support  cf  the  surface,  the  rein- 
forcement of  the  shaft-pillars  and  the  recovery 
of  pillars,  foot-wall,  and  broken  rock,  from 
abandoned  workings.  The  application  of  this 
method  must  not  be  confounded  with  that  of 
a  few  scattered  waste  packs  '  or  '  sticks,' 
which,  while  efficiently  supporting  thin  scales 


The  general  principles  involved  are  : 
Sand  or  gravel,  together  with  any  suitable 
refuse  that  may  be  at  hand,  is  transported  to 
some  form  of  bin  or  flat  sheet  close  to  the  shaft 
or  borehole  connected  with  the  workings  to  be 
filled.  Water  is  added  under  pressure  and  the 
resultant  pulp  is  led  through  pipes  or  launders 
into  a  stope  that  has  previously  been  prepared 
to  receive  it.  The  excess  water  is  drawn  oft 
through  the  sand,  and  after  settling  is  pumped 
to  the  surface  for  further  use. 

Surface  Arrangements.  —  In  metalli- 
ferous mines  the  material  used  will  almost  in- 


Sanc/  Oey/np 


S/o/c/n^   sane/  o/^f  damp 


Fig.  1. 


of  hanging  wall  or  purely  local  weight,  are 
absolutely  useless  against  a  '  creep  '  or  any 
serious  subsidence. 

Many  collieries  in  Silesia,  Westphalia,  and 
France  are  employing  this  method  of  filling 
their  workings  ;  the  majority  of  the  mining 
groups  on  the  Witwatersrand  have  adopted  it, 
and  from  private  information  and  current  liter- 
ature it  appears  that  a  large  number  of  mines 
in  Scotland  and  the  United  States  are  falling 
into  line.  Several  accounts  of  the  process  as 
practised  in  collieries  have  been  published  re- 
cently, more  especially  in  German  periodicals, 
and  this  article  will  deal  chiefly  with  the  me- 
thods adapted  to  metalliferous  mines,  and  used 
successfully  in  Johannesburg. 
4—5 


variably  be  tailing ;  in  collieries,  owing  to  an 
insufficient  supply  of  waste  products,  it  is  often 
necessary  to  procure  sand  or  gravel  from  some 
convenient  deposit.  Almost  any  sort  of  waste 
product  can  be  used,  but  the  efficiency  of  the 
pack  will  depend  largely  on  the  material  of 
which  it  is  composed.  Clean  quartz-sand  sets 
well  and  after  settlement  crushes  less  than  any 
other  material.  Experiments  have  shown  that, 
under  a  pressure  of  15001b.  per  square  inch, 
its  volume  is  only  diminished  by  3%.  On  the 
other  hand,  the  wearing  effect  on  pipes  is  most 
severe,  and  for  this  reason  a  small  proportion 
of  clay  is  often  added.  Clay  by  itself  is  not 
good,  as  it  retains  too  much  moisture  and  never 
sets.     Ashes  added  to  sand  assist  in  the  drain- 


295 


296 


THE    MINING    MAGAZINE 


age  of  the  water,  but  if  used  alone  crush  con- 
siderably under  pressure. 

On  the  Witvvatersrand  goldfield,  where  the 
removal  of  dumps  or  the  prevention  of  their 
further  growth  is  in  itself  a  commendable  ob- 
ject, only  sand  is  used,  taken  either  from  the 
cyanide  vats  direct  or  conveyed  from  the  near- 
est available  dump.  The  use  of  current  sand 
has  the  advantage  of  saving  a  second  handling, 
but,  on  the  other  hand,  some  expense  is  in- 
curred in  oxidizing  the  cyanide  compounds  re- 
maining in  the  sand,  to  prevent  the  formation 
of  prussic  acid  underground. 

After  lying  on  a  dump  for  some  weeks,  the 
sand  is  found  to  be  quite  free  from  cyanides, 
the  atmosphere  and  sulphides  having  no  doubt 
converted  them  into  prussic  acid,  which  has 
escaped  into  the  air. 

Where  the  quantity  of  current  sand  is  in- 
sufficient for  underground  requirements,  or 
where  it  is  inconvenient  to  connect  the  cyanide 
works  with  a  shaft,  recourse  is  had  to  the  alter- 
native of  conveying  sand  from  the  dump.  This 
entails  additional  cost  for  shovelling,  and,  if 
the  dumps  be  old  and  the  sand  acid,  a  con- 
siderable expenditure  on  lime  to  protect  the 
pipes  and  pumps. 

The  method  of  transport  depends,  of  course, 
on  local  conditions  ;  for  long  distances  a  me- 
chanical haulage  is  found  best ;  for  short  dis- 
tances a  belt-conveyor  or  sand  pump,  with 
subsequent  dewatering,  is  used ;  and  where 
the  dump  is  quite  close  to  the  entrance  to  the 
mine,  it  is  obviously  cheapest  to  hydraulic  the 
sand  directly  from  the  dump  to  the  shaft  or 
outcrop. 

This  last  method  can  be  extended  with  ad- 
vantage where  large-scale  filling  is  to  be  con- 
tinued for  a  considerable  period  by  driving  an 
inclined  tunnel  from  under  the  dump  or  cyanide 
vats  to  intersect  a  vertical  shaft  some  distance 
from  the  surface  (Fig.  1).  In  this  case  the 
sand  can  be  sluiced  from  the  vats  or  the  dump, 
and  run  down  the  tunnel  in  a  launder,  the  cost 
of  surface  transport  being  almost  negligible. 
When  a  dry  method  of  transport  is  used,  such 
as  mechanical  haulage  or  belt,  some  form  of 
bin  must  be  built  near  the  shaft,  the  main 
features  of  which  would  be  that  it  has  large 
storage  capacity,  so  that  loading  and  discharg- 
ing are  not  immediately  interdependent,  and 
that  it  can  be  discharged  easily  with  water,  so 
as  to  give  a  thick  pulp. 

A  good  form  consists  of  a  brick-lined  exca- 
vation, 40  ft.  long,  30  ft.  deep  and  12  ft.  wide, 
with  a  capacity  of  500  to  600  tons  (Fig.  2). 
The  bottom  of  the  bin  is  built  with  a  30%  fall 
towards  a  brick  partition,  on  the  other  side  of 


which  is  a  tunnel  from  which  the  flow  of  sand 
and  water  is  controlled  through  the  partition 
wall;  four  openings  (24 in.  high  and  12 in.  wide) 
are  left  in  the  brick-work,  and  into  these  the 
sluicing  nozzles  project.  The  opening  in  the 
nozzles  is  2  in.  by  i  in.  and  water  is  fed  under 
50  lb.  pressure.  The  pulp  flows  back  round 
the  nozzles  and  drops  into  a  launder  running 
with  a  fall  of  20%  to  the  shaft  or  borehole. 

Working  with  a  bin  of  this  description,  it  is 
possible  to  lower  sand  at  the  rate  of  200  to 
300  tons  per  hour,  the  pulp  containing  65%  of 
sand  by  weight.  Other  forms  of  bin  could  of 
course  bedevised.  One  consistingof  a  V-shap- 
ed hopper,  inclined  at  35",  is  at  present  under 
trial.  This  has  a  capacity  of  1000  tons,  and 
the  sand  is  sluiced  off  with  monitors. 

Pipes  and  Launders. — Where  the  flow 
of  the  pulp  lies  in  a  straight  line  and  at  an 
even  dip  of  12°  to  35°,  concrete-lined  launders 
have  been  found  satisfactory,  but  they  do  not 
provide  the  same  elastic  service  as  pipes,  which 
can  be  bent  and  laid  at  any  angle,  either  hori- 
zontal or  vertical. 

The  head  gained  in  vertical  and  steeply  in- 
clined sections  of  a  pipe-line  is  used  to  over- 
come the  friction  of  horizontal  or  even  slightly 
rising  sections,  whereas  launders  overflow  at 
any  grade  less  than  10%.  Pipes  have,  how- 
ever, the  disadvantage  of  being  liable  to  choke, 
and  are  subject  to  enormous  wear,  with  sub- 
sequent big  expense. 

Choking  can  be  prevented  almost  entirely 
by  avoiding  sudden  bends  in  the  line,  by  wash- 
ing out  the  pipes  before  and  after  use,  and  by 
using  grills  above  the  entrance  to  the  pipe. 
The  difficulty  of  excessive  wear  is  unfortu- 
nately not  so  easily  overcome,  but  a  longer  life 
is  secured  in  horizontal  and  inclined  sections 
by  turning  the  pipes  at  intervals.  In  the  case 
of  vertical  shafts,  however,  every  possible 
form  of  pipe  and  pipe-lining  has  been  tried, 
with  but  indifferent  success. 

An  ordinary  4  in.  black  pipe  in  a  vertical 
shaft  11 00  ft.  deep  showed  signs  of  wear  after 
20,000  tons  of  sand  had  been  passed  through 
it,  when  it  was  found  necessary  to  patch  a 
number  of  lengths.  The  average  wear  of  a 
length  proved  to  be  about  30,000  tons,  and 
some  of  the  piping  was  good  enough  to  be  used 
again  when  a  new  line  was  put  in. 

A  7  in.  pipe,  lined  to  five  inches  with  hard 
wood,  resisted  the  passage  of  32,000  tons  of 
sand  before  leaking;  but  taking  into  considera- 
tion the  cost  of  this  piping,  it  is  less  econo- 
mical than  the  unlmed  column  mentioned 
above. 

Porcelain-lined  pipes,  which  have  proved  so 


OCTOBER,    1911 


297 


mm 


LAUNDER    20%  GRADIENT 


WATER     PIPE5AND     NOZZLES   IN    SOLID    BLACK 


Fig.  a  (a)  SAND-BIN    PLAN 


De/a'/  o/^  Barr'caa'//7p 


Fig.  2  (6)  Sand-Bin,  End  ElevaHon. 


Drdin^ye  L  euncfer 


Fig.  3  (b  and  c)  Details  of  Reinforcement  of  Shaft-Pillar. 


298 


THE    MINING    MAGAZINE 


successful  in  Germany,  are  now  under  trial  in 
the  same  shaft,  but  have  up  to  date  not  been 
used  long  enough  to  establish  a  conclusive  test. 
Experiments  are  now  being  made  with  liners 
of  concrete,  belting,  earthenware,  and  wood 
pulp. 

Since,  however,  in  other  vertical  shafts  of 
less  depth,  the  rate  of  wear  has  been  found  to 
be  very  much  smaller,  it  has  been  decided  in 
future  to  break  the  pipe  every  200  or  250  ft., 
and  to  insert  a  box  with  the  purpose  of  check- 
ing the  velocity  of  the  stream.  The  last  300  ft. 
of  piping  in  the  shaft  will  be  left  intact,  in 
order  to  obtain  sufficient  head  to  force  the 
pulp  along  a  horizontal  drift  to  a  point  900  ft. 
from  the  bottom  of  the  shaft,  experiment  hav- 
ing proved  that  if  the  ratio  of  horizontal  to 
vertical  pipe  is  greater  than  3  :  1,  it  is  neces- 
sary to  dilute  the  pulp  with  more  water,  with 
a  corresponding  increase  in  the  pumping  cost. 

It  is  impossible  to  give  an  opinion  as  to 
whether  boreholes  will  prove  economical  as 
compared  with  vertical  pipes  for  filling  pur- 
poses, since  but  one  borehole,  and  that  only 
180  ft.  deep,  has  been  used  in  this  country,  but 
the  more  obvious  advantages  and  drawbacks 
may  be  outlined. 

The  main  advantage  of  a  borehole  is  that 
wear  is  of  no  moment,  and  there  can  be  no  ex- 
pense for  repairs  or  renewal  on  this  account. 
Secondly,  as  the  sand  is  not  conveyed  in  the 
shaft,  the  nuisance  of  any  spill  caused  by  leak- 
age does  not  exist. 

The  disadvantages,  although  individually 
not  serious,  collectively  make  the  extensive 
use  of  boreholes  very  doubtful.  The  original 
outlay  is  great,  being  about  five  times  the  cost 
of  piping  of  similar  size.  The  delay  due  to 
the  time  taken  in  drilling  is  a  serious  drawback 
if  there  is  a  necessity  for  immediate  filling. 
There  is  a  possibility  of  the  sand  eroding  any 
soft  strata  through  which  the  hole  passes, 
making  a  cavity,  and  allowing  the  strata  above 
to  fall  in  and  choke  the  hole.  It  is  more  diffi- 
cult to  clean  out  a  borehole  that  is  choked  than 
a  pipe  in  the  same  state.  For  the  last-named 
reason,  a  borehole  is  usually  left  open  at  the 
bottom,  and  the  advantage  of  the  head  of  sand 
due  to  the  vertical  depth  is  lost. 

Underground  Work. — The  method  of 
conveying  sand  underground  is  the  same  as 
that  for  conveying  water. 

Loose-flanged  piping  should  be  used  if  pos- 
sible, to  facilitate  the  turning  of  individual 
lengths  ;  the  joints  must  be  good  and  there 
should  be  as  few  bends  as  possible  in  the  line. 
Where  practicable  the  piping  should  be  on  a 
down  grade,  and  it  may  even  be  advisable  to 


sink  a  special  winze  in  order  to  avoid  an  ex- 
cess of  horizontal  or  rising  pipes. 

Barricading  is  the  most  important  part  of 
the  underground  work,  and  requires  consider- 
able care  and  experience.  Fig.  3  shows  a  small 
area  to  be  filled  next  to  a  shaft-pillar  which  is 
showing  signs  of  pressure ;  the  stope  is  6  ft. 
high  and  dipping  at  30°.  Round  sticks  10  to 
12  in.  diam.  are  lined  up  at  4-ft.  intervals,  well 
hitched  into  the  foot- wall,  and  either  hitched 
or  pegged  in  the  hanging  wall.  On  to  these 
are  nailed  1 1  in.  deals,  carefully  butted  against 
one  another,  and  cut  so  that  they  join  in  the 
middle  of  an  upright.  The  joint  between  the 
timber  and  the  hanging  wall,  foot-wall  or 
pillar,  must  be  made  most  carefully  ;  the  deals 
are  checked  to  fit  the  unevenness  of  the  rock 
and  hammered  down  on  to  the  solid.  Any 
crevices  still  showing  are  caulked  with  sack- 
ing, straw,  or  oakum,  which  is  held  in  place 
by  small  pieces  of  wood  laid  on  a  bevel.  If 
the  work  is  done  well,  after  a  few  hours  no 
sand  or  slime,  but  only  a  little  clean  water, 
will  come  through  the  barricade. 

Clay  and  cement  have  been  tried  in  place 
of  caulking,  but  are  not  successful,  as  the 
former  washes  away  and  the  latter  is  too 
rigid.  Where  the  stope  is  high,  say  20  ft.,  a 
waste  pack  faced  with  cement  is  sometimes 
used  as  a  bottom  barricade.  If  the  material 
used  for  packing  is  coarse,  a  rough  waste 
pack  covered  with  filter  matting  may  be  used 
with  success,  but  when  slime  is  present,  the 
pores  of  the  matting  become  choked  and  im- 
pervious to  water :  the  weight  of  the  pulp 
forces  the  matting  into  the  crevices  between 
the  rocks,  and  the  matting  is  torn  and  allows 
the  pulp  to  come  through. 

For  side  barricades,  any  of  the  methods 
mentioned  above  may  be  used.  When  filling 
only  small  quantities,  the  sand  itself  may  be 
thrown  up  to  form  a  wall  in  the  same  way  as 
is  usual  in  building  a  slime-dam.  The  sand 
should,  where  possible,  be  led  into  a  stope  at 
the  side  where  the  barricade  is  least  strong, 
as  the  coarse  sand  settles  first  and  exerts  less 
pressure  than  the  slime. 

Where  a  large  section  of  a  mine  is  caving 
and  is  to  be  held  up  to  support  the  surface  or 
to  stop  movement  in  the  shafts,  a  different 
procedure  is  adopted. 

In  Fig.  4  almost  all  the  stoped  area  is  to  be 
filled,  every  other  consideration  being  ne- 
glected in  order  to  ensure  the  safety  of  the 
mine.  In  this  case  there  are  no  side  barri- 
cades and  the  area  to  be  supported  at  the 
bottom  is  small. 

Under    these    circumstances    no    expense 


OCTOBER,    1911 


299 


Fig.  3  (a)    REINFORCEMENT    OF   SHAFT   PILLAR. 


%:  ,.  So//c/  6rOcfr)(/ 

Fig.  4.    FILLING    ON    A    LARGE    SCALE. 


300 


THE    MINING    MAGAZINE 


would  be  spared  in  making  the  barricade  and 
dams  quite  secure  ;  the  uprights  would  be  15 
in.  or  more,  and  the  deals  either  3  in.  or  two 
thicknesses  of  H  in.  The  dams  across  the 
drifts  would  be  masonry,  or,  if  there  were  any 
local  movement,  pitch-pine  blocks  three  feet 
long,  tapered  from  12  by  12  to  10  by  10, 
would  be  preferable.  In  a  case  of  this  sort 
filling  could  be  carried  on  from  two  plants, 
double-shift,  and  100,000  tons  could  be  low- 
ered every  month.  With  regard  to  pillars 
and  blocks  ot  ground  left  standing,  these 
would  be  recovered  after  the  sand  had  drained, 
by  opening  up  the  drifts  and  rising  to  the  re- 
quired spot. 

Such  a  method  of  filling  might  delay  the 
working  of  this  remaining  ground  for  a  year 
or  more,  but  the  whole  of  it  would  be  removed 
with  safety,  and  in  addition  to  attaining  the 
desired  object,  an  actual  profit  might  be  made 
from  pillars  that  could  never  be  recovered 
otherwise. 

The  drainage  of  the  sand  is  of  great  im- 
portance, and  can  be  arranged  in  several 
ways.  The  usual  method  is  to  carry  a  laun- 
der through  a  barricaded  boxhole  up  the 
stope,  and  to  close  it  with  slats  as  the  sand 
rises.  The  launder  is  placed  as  far  as  pos- 
sible from  the  point  where  the  pulp  enters 
the  stope,  so  that  by  the  time  the  water  reaches 
it,  most  of  the  sand  has  settled.  In  cases 
where  the  ground  to  be  filled  is  so  caved  that 
it  would  be  expensive  to  make  a  way  for  the 
launder,  a  filter  is  laid  just  inside  the  barri- 
cade ;  this  is  composed  of  several  2-in.  pipes 
perforated  with  I'm.  holes  and  covered  first 
with  coarse  rock,  then  smaller  pieces,  and 
finally  ashes.  The  total  filter  bed  is  about 
four  feet  thick  and  acts  successfully. 

From  the  sand-pack  the  water  is  led  into 
settling-sumps  built  in  old  stopes,  and  escapes 
finally  over  a  long  horizontal  overflow  weir 
to  the  main  sump. 

In  discussing  the  instalment  of  a  plant  for 
this  method  of  supporting  a  mine,  the  effect 
of  the  following  local  conditions  must  be  taken 
into  account :  In  the  case  of  steeply  inclined 
lodes,  the  barricade  must  be  built  stronger 
than  described  above.  When  a  small  quan- 
tity of  water  is  floAving  from  the  hanging  wall 
or  foot-wall  of  a  stope  to  be  filled,  it  must 
either  be  isolated  and  piped  through  the  sand 
or  a  large  filter-bed  must  be  laid  at  the  bot- 
tom of  the  stope. 

The  process  cannot  be  recommended  for 
areas  in  which  large  quantities  of  water  are 
appearing,  unless  natural  boundaries,  such  as 
dikes  or  pillars,  can  be  used  in  place  of  barri- 


cades. Under  normal  circumstances,  as  de- 
scribed in  this  article,  the  barricade  can  be 
pulled  down  six  months  after  filling  is  com- 
pleted, and  the  sand  will  be  found  to  remain 
standing  vertically  in  a  hard  compact  mass. 

Most  of  the  leading  mining  engineers  in 
Johannesburg  have  inspected  the  process,  and 
they  are  almost  unanimous  in  agreeing  that 
it  is  fulfilling  the  claims  made  for  it,  and  will 
prove  of  great  value  on  the  Witwatersrand. 

The    output   of   minerals    and    metals 
throughout  the  world  during   1909  forms  the 
subject  of  a  Government  publication  issued  at 
the  end  of  September.     The  figures  are  be- 
lated, but  as  the  strength  of  a  chain  is  that  of 
the  weakest  link,  so  is  the  completion  of  world's 
statistics  delayed  by  the  unenterprising  states 
and  countries.     The  total  value  of  the  output  is 
estimated    at    ;^865,000,000,    of   which    coal 
represented  ;^400,000,000.  The  output  of  coal 
throughout  the  world  was  1,113,308,386  tons, 
of  which  268,007,257  tons  was  mined  in  the 
British   Isles,  37,751,869   tons   elsewhere   in 
the  British  Empire,  418,038,117  tons  in  the 
United    States,    217,445,656    tons    in    Ger- 
many, 48,812.901   tons  in  Austria-Hungary, 
37,840,086  tons  m  France,  24,455,340  tons  in 
Russia,  and  23,517,550  tons  in  Belguim.  Over 
6  million  people  were  employed  in  mining  and 
of  these  more  than  half  are  at  the  coal  mines. 
As  regards  petroleum,  India  yielded  938,466 
tons  and  Canada  57,549.     These  are  the  only 
productions  reported  throughout   the   British 
Empire.     The  figures  for  the  rest  of  the  world 
were  38,992,088  tons  of  which  24,288756  tons 
were  produced  in  the  United  States,  8,435,072 
tons  in  Russia,  2,088,931  tons  in  Austria-Hun- 
gary, 2,012,898  tons  in  the  Dutch  East  Indies, 
and    the    remainder  in  smaller  quantities  in 
Roumania,    Mexico,    Japan,    Germany,    and 
Peru.     The  output  of  metals  is  calculated  as 
the  amount  extracted  from  the  ores  mined  in 
each  country  and  not  the  production  in  each 
country  from  domestic  and  imported  ores.   In 
Great  Britain  the  yield  of  iron  was  4,879,226 
tons,  and  in  the  rest  of  the  British  Empire 
706,843   tons,  of  which  nearly  the  whole  is 
credited  to  Newfoundland  and  Canada.     The 
rest  of  the  world  produced  52,822,822  tons, 
of  which    the    United    States   accounted    for 
26,209,678    tons,    Germany    7,098,470    tons, 
Spain  4,315,600  tons,  France  4,205,489  tons, 
Russia  2,622,419  tons,  Sweden  2,382,540  tons, 
Luxemburg  2,085,806  tons,  Austria- Hungary 
1,910,000  tons,   and    eleven    other   countries 
smaller  quantities,  Cuba,  Algeria,  Italy,  and 
Greece  being  the  most  important. 


OCTOBER,    1911 


301 


DISCUSSION 

Our  readers  are  invited  to  criticize  anything  appearing  in  this 
magazine  and  to  discuss  other  subjects  of  general  technical 
interest. 

Nipissing. 

The  Editor  : 

Sir — The  story  of  the  original  purchase  of 
the  Nipissing,  as  told  on  page  94  of  the  August 
issue  of  The  Mining  Magazine,  is  interesting, 
but  it  lacks  the  essential  element  of  truth.  As 
years  pass  and  men's  memories  become  dim, 
fantastic  tales  are  told  of  the  discovery  of  im- 
portant mineral  deposits  and  the  rise  of  mineral 
industries.  We  are  told,  for  instance,  that  a 
certain  prospector,  in  order  to  learn  the  loca- 
tion of  a  rich  vein  discovered  by  an  Indian 
tribe,  married  the  daughter  of  the  chief.  An- 
other prospector  is  stated  to  have  made  an  im- 
portant find  through  throwing  his  hammer  at 
one  of  the  shyest  of  animals,  a  fox.  In  going 
to  pick  up  the  hammer,  he  found  it  lying  on 
a  valuable  orebody.  Again,  one  of  the  dis- 
coverers of  corundum  in  Ontario  is  said  to  have 
made  the  find  in  the  winter.  He  was  wearing 
deer-skin  moccasins  and  felt  the  rough  surface 
of  the  corundum  rock  through  the  snow! 

I  think  the  following  notes  and  copies  of 
correspondence  will  make  clear  how  Mr.  E.  P. 
Earle  came  to  purchase  the  Nipissing  mine. 

In  November  1903  I  received  a  sample  of 
ore  in  Toronto  from  Haileybury.  This  sample 
was  niccolite  (kupfer-nickel),  which  the  finder 
thought  was  copper  ore.  A  few  days  later  I 
visited  the  locality  and  saw  the  remarkable 
assemblage  of  minerals  in  the  veins  that  has 
been  frequently  described.  On  my  return  to 
Toronto  I  wrote  a  paper  for  the  Engineering 
and  Mining  Journal  of  New  York,  published 
on  December  10,  1903.  This  paper  was  later 
re-published  in  the  Canadian  Mining  Review. 
It  was  also  re-printed  as  a  pamphlet,  and 
copies  of  the  pamphlet  were  sent  to  persons 
throughout  the  world  who,  I  thought,  might  be 
interested  in  the  ores.  At  that  time  Mr.  Earle 
had  an  advertisement  in  the  Engineering  and 
Mining  Journal  to  the  effect  that  he  was  a 
purchaser  of  rare  minerals.  A  copy  of  the 
pamphlet  w^as  sent  to  him.  The  result  was 
that  Mr.  Earle  wrote  the  following  letter  to 
me  : 

"  29  Liberty  St., 

New  York, 
January  30,  1904. 
Dear  Sir — I  am  in  receipt  of  your  paper 
on  the  subject  of  cobalt-nickel  ores  in  On- 
tario, and  have  read  the  same  with  much 
interest.  In  the  last  paragraph  of  your  paper 
I  note  that  you  are  willing  to  put  buyers  of 
cobalt  ores  in  communication  with  producers. 


I  make  a  specialty  of  rare  minerals  and  am 
always  in  the  market  for  cobalt  ores,  and  will 
be  greatly  obliged  if  you  will  be  kind  enough 
to  give  me  the  names  of  some  of  the  more 
important  producers  of  the  mineral. 

Thanking  you  in  advance  for  your  attention, 
I  remain. 

Yours  very  truly, 
E.  P.  Earle." 
The  following  is  a  copy  of  my  letter  to  Mr. 
Earle  : 

"  Bureau  of  Mines, 

Toronto, 
February  4,  1904. 
Dear  Sir — I  am  in  receipt  of  your  letter 
of  January  30.  Messrs.  A.  Ferland  and  W, 
C.  Chambers,  whose  address  is  Haileybury, 
Ontario,  are  mining  the  cobalt  ores  to  which 
you  refer.  You  might  write  to  them  as  to 
quantity  which  they  can  supply,  etc. 

I  shall  be  pleased  to  give  you  further  in- 
formation at  any  time  on  this  subject. 
Yours  very  truly, 

W.  G.  Miller. 
Provincial  Geologist." 
The  gentlemen  whose  names  I  gave  to  Mr. 
Earle  in  this  letter  were  two  out  of  the  five 
original  owners  of  the  Nipissing,  the  others 
being  W.  B.  Russell,  R.  K.  Russell,  and  R. 
Galbraith.  Later  on  Mr.  Earle  visited  Hailey- 
bury and  Cobalt.  The  purchase  of  the  pro- 
perty was,  however,  not  completed  until  the 
autumn  of  1904.  The  original  owners  had 
some  prospecting  done  during  the  summer  but 
did  not  discover  any  veins.  Two  had  been 
found  on  the  property  in  1903. 

W.  G.  Miller. 
Toronto,  August  30. 

Speculation  in  Mining. 

The  Editor : 

Sir — The  discussion  in  The  Mining  Maga- 
zine on  the  speculative  character  of  the  min- 
ing business  is  not  entirely  new,  as  witness 
the  following  from  George  Agricola,  De  Re 
Metallica,  Book  I.,  Basel,  1556. 

H.  C.  Hoover. 

London,  September  7. 

"  Since  there  has  always  been  the  greatest 
disagreement  amongst  men  concerning  metals 
and  mining,  some  praising,  others  utterly  con- 
demning them,  I  have  decided  that  before  im- 
parting my  instruction  I  should  carefully  weigh 
the  facts  with  a  view  to  discovering  the  truth 
in  this  matter. 

So  I  may  begin  with  the  question  of  utility, 
which  is  a  two-fold  one,  for  either  it  may  be 
asked  whether  the  art  of  mining  is  really  pro- 


302 


THE    MINING    MAGAZINE 


fitable  or  not  to  those  who  are  engaged  in  it, 
or  whether  it  is  useful  or  not  to  the  rest  of 
mankind.     Those  who  think  mining  of  no  ad- 
vantage to  the  men  who  follow  the  occupation, 
assert,  first,  that  scarcely  one  in  a  hundred  who 
dig  metals  or  other  such  thmgs  derive  profit 
therefrom, and  again,  that  miners,  because  they 
entrust  their  certain  and  well-established  wealth 
to  dubious  and  slippery  fortune  generally  de- 
ceive themselves,  and,  asaresult,  impoverished 
by  expenses  and  losses,  in  the  end  spend  the 
most  bitter  and  most  miserable  of  lives.     But 
persons  who  hold  these  views  do  not  perceive 
how  much  a  learned  and  experienced  miner 
differs  from  one  ignorant  and  unskilled  in  the 
art.  The  latter  without  any  careful  discrimina- 
tion digs  out  the  ore,   while  the  former  first 
assays  and  proves  it,  and  when  he  finds  the 
veins  either  too  narrow  and  hard,  or  too  wide 
and  soft,  he  infers  therefrom  that  these  cannot 
be  mined  profitably,  and  so  works  only  the  ap- 
proved ones.  What  wonder  then  if  we  find  the 
incompetent  miner  suffers  loss,  while  the  com- 
petent one  is  rewarded  by  an  abundant  return 
from  his  mining  ?     The  same  thing  applies  to 
husbandmen.     For  those  who  cultivate  land 
which  is  alike  arid,  heavy,  and  barren,  and  in 
which  they  sow  seeds,  do  not  make  so  great  a 
harvest  as  those  who  cultivate  a  fertile  and 
mellow  soil  and  sow  their  grain  in  that.     And 
since  by  far  the  greater  number  of  miners  are 
unskilled  rather  than  skilled  in  the  art,  it  fol- 
lows that  mining  is  a  profitable  occupation  to 
very  few  men,  and  a  source  of  loss  to  many 
more.     Therefore  the  mass  of  miners  who  are 
quite  unskilled  and  ignorant  in  the  knowledge 
of  veins  often  lose  both  time  and  trouble.  Such 
men  are  accustomed  for  the  most  part  to  take 
to  mining  when  either  through  being  weighted 
with  the  fetters  of  large  and  heavy  debts  they 
have  abandoned  their  ordinary  business,  or  in 
a  desire  to  change  their  occupation  have  left 
the  reaping-hook  and  plough.  And  so  if  at  any 
time  such  a  man  discover  rich  veins,  or  other 
abounding  mining  produce,  this  occurs  more 
by  good  luck  than  through  any  knowledge  on 
his  part. 

;!<  ;;;  :'f.  * 

Again,  those  who  condemn  the  mining  in- 
dustry say  that  it  is  not  in  the  least  stable,  and 
they  glorify  agriculture  beyond  measure.  But 
I  do  not  see  how  they  can  say  this  with  truth, 
for  the  silver  mines  at  Freiberg  and  Meissen 
remain  still  unexhausted  after  400  years,  and 
the  lead  mines  of  Goslar,  after  600  years.  The 
proof  of  this  can  be  found  in  the  monuments 
of  history.  The  goldand  silver  minesbelonging 
to  the  communities  of  Schemnitz  and  Cremnitz 


have  been  worked  for  800  years,  and  these 
latter  are  said  to  be  the  most  ancient  privileges 
of  the  inhabitants.  Some  also  say  the  profit 
from  an  individual  mine  is  unstable,  and  if, 
forsooth,  the  miner  is,  or  ought  to  be  depen- 
dent on  only  one  mine,  and  as  if  many  men  do 
not  bear  in  common  their  expenses  in  mining, 
or  as  if  one  experienced  in  his  art  does  not  dig 
another  vein  if  fortune  does  not  amply  respond 
to  his  prayers  in  the  first  case.  The  New 
Schonberg  at  Freiberg  has  remained  stable 
beyond  the  memory  of  man. 

It  is  not  my  intention  to  detract  anything 
from  the  dignity  of  agriculture,  and  that  the 
profits  of  mining  are  less  stable,  I  will  always 
and  readily  admit,  for  the  veins  do  in  time 
cease  to  yield  metals,  whereas  the  fields  bring 
forth  fruits  every  year.  But  though  the  busi- 
ness of  mining  may  be  less  reliable,  it  is  more 
productive,  so  that  in  reckoning  up  what  it  is 
wantmg  in  stability  is  found  to  be  made  up  by 
productiveness.  Indeed,  the  yearly  profit  of 
a  lead  mine,  in  comparison  with  the  fruitful- 
ness  of  the  best  fields,  is  three  times  or  at 
least  twice  as  great. 

The  following  are  some  of  the  wicked  and 
sinful  methods  by  which  they  say  men  obtain 
riches  from  mining.  When  a  prospect  of  ob- 
taining metals  shows  itself  in  a  mine,  they 
contend  that  either  the  ruler  or  magistrate 
drives  out  the  rightful  owners  of  the  mines 
from  possession,  or  a  shrewd  and  cunning 
neighbour  perhaps  brings  a  law-suit  against 
the  old  possessors  in  order  to  rob  them  of  some 
part  of  their  property.  Or  the  mine  superin- 
tendent imposes  on  the  owners  such  a  heavy 
contribution  on  shares  that  if  they  cannot  or 
will  not  pay,  they  lose  their  rights  of  posses- 
sion, while  the  superintendent,  contrary  to  all 
that  is  right,  seizes  upon  all  that  they  have 
lost.  Or,  finally,  the  mine  foreman  may  con- 
ceal the  vein  by  plastering  over  that  part  where 
the  metal  abounds,  with  clay,  or  by  covering 
it  with  earth,  stones,  stakes,  or  poles,  in  the 
hope  that  after  several  years  the  proprietors, 
thinking  the  mine  exhausted,  will  abandon  it, 
and  the  foreman  can  then  excavate  that  re- 
mainder of  the  ore  and  keep  it  for  himself. 
They  even  state  that  the  scum  of  the  miners 
exist  wholly  by  fraud,  deceit,  and  lying.  For 
to  speak  of  nothing  else,  but  only  of  those  de- 
ceits which  are  practised  in  buying  and  selling 
shares,  it  is  said  they  either  advertise  the  veins 
with  false  and  imaginary  praises,  so  that  they 
can  sell  the  shares  in  the  mines  at  one-half  more 
than  they  are  worth,  or  on  the  contrary,  they 
sometimes  detract  from  the  estimate  of  them 


OCTOBER,    1911 


303 


so  that  they  can  buy  shares  for  a  small  price. 
By  exposing  such  frauds  our  critics  suppose 
all  good  opinion  of  miners  is  lost.  Now,  all 
wealth,  whether  it  has  been  gained  by  good  or 
evil  means,  is  liable  by  some  adverse  chance 
to  vanish  away.  It  decays  and  is  dissipated 
by  the  fault  and  carelessness  of  the  owner, 
since  he  loses  it  through  laziness  and  neglect, 


doubts  thetrustworthmess  of  a  seller  or  buyer, 
goes  at  once  to  the  mine  himself  that  he  may 
for  himself  examine  the  vein  which  has  been 
so  greatly  praised  or  disparaged,  and  may  con- 
sider whether  he  will  buy  or  sell  the  shares  or 
not.  But  people  say,  though  such  an  one  can 
be  on  his  guard  against  fraud,  yet  a  simple 
man  and  one  who  is  easily  credulous  is  de- 


AX    ILLUSTRATION    FROM    AGRICOLA. 


or  wastes  and  squanders  it  in  luxuries,  or  he 
consumes  and  exhausts  it  in  gifts,  or  he  dis- 
sipates and  throws  it  away  in  gambling. 

-,T  -a-  -,c  -.c 

The  mine  superintendent  cannot  exact  calls 
from  the  owners  without  the  knowledge  and 
permission  of  the  Bergmeister  or  the  Deputies. 
For  this  reason  deception  of  this  kind  is  im- 
possible. Should  the  foremen  be  convicted  of 
fraud,  they  are  beaten  with  rods  ;  or  of  theft, 
they  are  hanged.  It  is  complained  that  some 
sellers  and  buyers  of  the  shares  in  mines  are 
fraudulent.  I  concede  it.  But  can  they  de- 
ceive anyone  except  a  stupid,  careless  man, 
unskilled  in  mining  matters  ?  Indeed,  a  wise 
and  prudent  man,  skilled  in  this  art,   if    he 


ceived.  But  we  frequently  see  a  man  who  is 
trying  to  mislead  another  in  this  way  deceive 
himself,  and  deservedly  become  a  laughing- 
stock for  everyone.  For  very  often  the  de- 
faulter as  well  as  the  dupe  is  entirely  ignorant 
of  mining.  If,  for  instance,  a  vein  has  been 
found  to  be  abundant  in  ore,  contrary  to  the 
idea  of  the  would-be  deceiver,  then  he  who 
was  to  have  been  cheated  gets  a  profit,  and  he 
who  has  been  the  deceiver  loses.  Neverthe- 
less, the  miners  themselves  rarely  buy  or  sell 
shares,  but  generally  they  have  jurati  vendi- 
tores  (brokers  ?)  who  buy  and  sell  at  such 
prices  as  they  have  been  instructed  to  give  or 
accept. 


304 


THE    MINING    MAGAZINE 


But  to  bring  this  discussion  to  an  end,  in- 
asmuch as  the  chief  calHngs  are  those  of  the 
moneylender,  the  soldier,  the  merchant,  the 
farmer,  and  the  miner,  I  say  that  inasmuch  as 
usury  is  odious,  while  the  spoil  cruelly  cap- 
tured from  the  possessions  of  the  people  inno- 
cent of  wrong  is  wicked  in  the  sight  of  God 
and  man,  and  inasmuch  as  the  calling  of  the 
miner  excels  in  honour  and  dignity  that  of  the 
merchant  trading  for  lucre,  while  it  is  not  less 
noble  though  far  more  profitable  than  agricul- 
ture, who  can  fail  to  realize  that  mining  is  a 
calling  of  peculiar  dignity  ?  Certainly,  though 
it  is  but  one  of  important  and  excellentmethods 
of  acquiring  wealth  in  an  honourable  way,  a 
careful  and  diligent  man  can  attain  this  result 
in  no  easier  way  than  by  mining." 

Ball-Mill  Practice. 

The  Editor  : 

Sir — I  have  read  with  great  interest  the  valu- 
able contribution  of  Mr.  M.  W.  von  Berne- 
witz  in  your  August  issue.  Metallurgists  will 
agree  that  Kalgoorlie  practice  is,  as  far  as  dry 
crushing  with  ball-mills  is  concerned,  far  ahead 
of  other  districts  in  efficiency  and  low  working 
costs. 

In  my  opinion  we  have  not  yet  had  suffi- 
cient proof  that  wet-crushing  ball-mills  are  as 
efficient  as  heavy  gravity  stamps  on  hard  dense 


Milling '  the  author  states  that  a  Krupp  mill 
had  a  greater  output  than  a  10-stamp  battery, 
but  does  not  give  details. 

The  following  is  an  instance  of  a  No.  5 
Krupp  wet-crushing  ball-mill  working  on  hard 
dense  quartz  in  comparison  with  light  gravity 
stamps.  In  the  third  column  I  have  put  the 
output  of  the  Simmer  Deep- Jupiter  mill,  having 
taken  the  data  from  Caldecott's  paper  on  heavy 
gravity  stamps  in  Vol.  XIX  of  the  Transactions 
of  the  Institution  of  Mining  and  Metallurgy. 

I  should  not  like  to  contract  to  erect  a  No. 
5  ball-mill  in  24  hours  with  28  men,  for  to  my 
mind  the  building  of  a  ball-mill  is  not  so  easy 
as  the  author  would  lead  one  to  believe.  He 
reminds  me  of  the  miner's  wife  whose  husband 
was  grumbling  about  going  to  work  on  the 
first  shift  of  the  week  at  night.  The  good 
lady  remarked  :  "  Why  there  is  only  to-night, 
to-morrow  night,  the  night  after  that,  and  three 
more  nights,  and  you  are  finished." 

Donald  F.  Foster. 

Parral,  Mexico,  September  7. 

Most  Productive  Gold  Mine. 

The  Editor  : 

Sir — Being  in  a  somew'hat  critical  mood 
when  I  took  up  your  August  issue,  I  noted  in 
the  editorials  two  statements  to  which  I  take 
exception.     The  more  important  is  on  page 


Weight  of  Balls  or  Stamps 

Drop  in  Inches 

Screen  Aperture 

Revolutions  or  Drops  per  minute. 

Tonnage  per  24  hours 

Grading  : 

On  30  mesh  %  

„    40 

n    60 

„    80 

„    90 

Through    90 

On  100 

,,150 

Through  150 


Ball-mill 


Light  Gravity  Stamps 


1000  kilo 
2200  lb. 

4 
0"0312 

24 

30 

33'4 

ir8 

19"9 

7"8 


ro 

0'6 
25"5 


10  of  850  lb. 

5  of  750  lb. 

6 

0"0312 

102 

30 


Simmer  Deep-Jupiter 
Heavy  Stamp 


1600  lb. 

8 

0"028 

96 

8'31 


317 
16*5 

5r8 


ores,  although  they  show  to  advantage  when 
compared  with  light  gravity  stamps  and  would 
probably  compare  favourably  with  the  heavy 
stamp  on  soft  friable  ores.  I  take  it  that  the 
heavy  stamp  is  suitable  for  hard  ores,  not  soft 
ones. 

On  page  81   of  Warnford   Lock's   '  Gold 


101,  where  you  refer  to  the  Crown  Mines  as 
"  forming  the  most  productive  gold  mining 
property  in  the  world,"  and  state  that  the  net 
profit  for  the  first  half  of  1911  was  the  equiva- 
lent of  about  $3,000,000.  The  term  '  produc- 
tive,' as  used  here,  is  not  definite.  Assuming 
that  you  mean  productive  to  shareholders,  I 


OCTOBER,    1911 


305 


would  call  your  attention  to  the  enclosed  clip- 
ping anent  the  production — net  profit — of  the 
Goldfield  Consolidated  Mines  for  the  same 
period.  You  will  note  that  the  net  profit 
reaches  the  magnificent  total  of  $4,240,754, 
over  40%  greater  than  the  net  profit  of  the 
Crown  Mines.  During  the  first  half  of  1911 
this  company  distributed  $3,558,367  in  divi- 
dends. The  Rand  amalgamation  does  not  yet 
deserve  the  palm. 

Having  read  many  of  Claude  T.  Rice's 
articles  with  much  profit,  I  was  amazed  at 
your  attack  on  him  on  page  96.  In  that 
editorial  you  lead  your  readers  to  infer  that 
his  writings  are  not  trustworthy  because  of 
his  connection  with  the  campaign  of  Mines 
and  Methods  against  Utah  Copper.  A  per- 
usal of  the  columns  of  the  Engineering  and 
Mining  Journal  would  show  Mr.  Rice  to  be 
one  of  its  frequent  contributors.  His  connec- 
tion with  Mines  and  Methods  was  severed 
nearly  a  year  and  a  half  ago,  that  is,  in  May 
1910,  as  Mines  and  Methods  announces  in  its 
issue  of  August  1910.  In  a  later  number, 
not  now  at  hand,  that  paper  assails  Mr.  Rice 
himself,  while  admitting  that  he  had  had  no 
connection  with  its  assaults  on  Utah  Copper. 

L.  O.  H. 

Cleveland,  Ohio,  September  14. 

[We  are  always  willing  to  publish  correc- 
tions or  views  contrary  to  our  own.  We  were 
not  aware  that  Mr.  Rice  left  Mines  and 
Methods  so  long  ago.  He  has  transferred 
his  services  to  various  periodicals  four  times 
within  four  years,  so  that  our  error  is  pardon- 
able. Our  correspondent,  however,  is  quite 
mistaken  in  suggesting  that  Mr.  Rice  had  "no 
connection  with  the  assaults  on  Utah  Copper" 
to  which  we  referred.  He  not  only  attacked 
the  Utah  Copper  company  but  maintained  a 
vendetta  against  Mr.  D.  C.  Jackling,  the  man- 
ager of  that  company. — Editor.] 

Slime  Settlement. 

The  Editor : 

Sir^ — My  eye  has  caught  the  precis  of  an 
article  on  slime  settlement  as  it  appears  in 
your  issue  of  August,  on  page  149.  Mr.  B.  L. 
Gardner  is  quite  wrong  in  claiming  novelty  for 
the  device.  I  adapted  it  to  slime  settlement 
at  Conchefio  some  14  years  ago,  and  Mr. 
Robert  H.  Richards  has  given  me  full  credit, 
describing  and  figuring  it  in  his '  Ore  Dressing,' 
Vol.  1,  page  459.  As  it  is  a  remarkable  settler, 
and  as  I  had  the  honour  of  introducing  it  into 
the  mining  field,  I  do  not  wish  to  lose  credit 
therefor.  As  Mr.  Gardner  must  be  familiar 
with  the   great   authority   in   English  on  ore 


dressing,  I  imagine  he  must  have  seen  this  in 
Richards'  book  and  later  have  forgotten  where 
he  received  the  suggestion. 

COURTENAY  DeKaLB. 

Fundicion,  Mexico,  September  8. 

Ventilation  in  Mines. 

The  Editor  : 

Sir — in  your  issue  of  May  you  do  me  the 
honour  to  review  my  paper  on  '  A  Standard 
of  Adequate  Ventilation  at  Metal  Mines  '  re- 
cently read  before  the  Australasian  Institute 
of  Mining  Engineers.  In  your  review  you 
consider  some  of  the  arguments  advanced  by 
me  as  reactionary.  Will  you  kindly  permit 
me  to  reply  ?  One  of  two  things  must  have 
happened  ;  either  I  have  not  in  my  paper  made 
myself  sufficiently  explicit,  or  you  have  imper- 
fectly grasped  the  arguments  I  advanced. 

Upon  reference  to  the  text  of  my  paper,  you 
will  find  that  I  said  :  "  (7)  That  the  volume 
constituting  an  adequate  amount  of  air,  within 
the  meaning  of  the  law,  is  not  ascertainable 
by  the  rule-of-thumb  formula  of  a  quantity 
standard,  but  may  only  be  found  from  the 
analysis  and  temperature  of  the  mine  air." 
Upon  page  7  you  will  also  find  that  I  endorse 
the  British  regulation  as  regards  adequate  ven- 
tilation, and  that  I  state  that  successive  Royal 
Commissions  have  approved  of  it  and  have  left 
it  unaltered.  This  regulation  is  as  follows  : 
"  An  adequate  amount  of  ventilation  shall  be 
constantly  produced  in  every  mine  to  dilute 
and  render  harmless  noxious  gases  to  such  an 
extent  that  the  working  places,  levels,  stables, 
and  workings  of  the  mine  and  the  travelling 
roads  to  and  from  those  working  places  shall 
be  in  a  fit  state  for  working  and  passing  there- 
in." You  will  observe  that  no  fixed  standard 
is  here  given.  In  no  place  in  my  paper  do  I 
suggest  the  fixing  by  statute  of  a  standard  of 
ventilation,  and  nowhere  in  the  report  of  the 
British  Royal  Commission  on  Mines  1909  is 
such  a  thing  proposed. 

Regarding  the  standard  I  was  advocating, 
namely,  a  minimum  of  19%  by  volume  of 
oxygen  and  not  more  than  lj%  of  CO 2,  I 
specially  stated  that  I  did  not  suggest  that 
these  proportions  should  constitute  a  demar- 
cation between  adequate  and  inadequate  ven- 
tilation, but  rather  as  a  readily  detected  stan- 
dard (by  its  effect  on  lights)  to  be  used  by 
inspectors  and  others  who  may  require  infor- 
mation of  the  state  of  the  air  in  a  mine,  this 
to  be  followed  by  analysis  if  necessary.  The 
whole  tenor  of  my  paper  was  against  a  fixed 
standard  that  can  not  always  be  maintained, 
but  rather  in  advocacy  of  a  practical  standard 


306 


THE    MINING    MAGAZINE 


that  would  be  regarded  as  reasonable  by  those 
famihar  with  mining  conditions. 

From  experience  gained  as  an  Inspector  of 
Mines  both  in  AustraHa  and  New  Zealand,  I 
can  affirm  that  if  one  section  of  a  mining 
statute  is  so  weak  as  to  permit  disregard,  there 
will  certainly  be  other  sections  with  regard 
to  which  mine  officials  will  request  equal 
clemency,  and,  in  common  with  Dr.  Haldane 
and  Professor  Cadman,  I  believe  that  the 
British  Factories  Standard  of  CO2,  namely, 
25  parts  by  volume  in  10,000  parts  of  air,  to 
be  unnecessarily  strict  for  mines,  giving  my 
reasons  for  such  an  opinion.  In  the  most  ade- 
quately ventilated  metal  mines  conditions  may 
arise  where  such  a  standard  would  be  unat- 
tainable except  at  considerable  cost  and  after 
harassing  delay,  for  example  in  rises,  cross- 
cuts, or  '  dead  '  ends  approaching  other  work- 
ing places,  when  for  a  brief  period  the  air  is 
more  or  less  heated  and  vitiated,  especially 
after  blasting.  If  the  strict  standard  sugges- 
ted in  your  leading  article  were  here  enforced, 
it  would  usually  be  necessary  to  stop  work  to 
install  a  supplementary  mechanical  ventilator 
adjacent  to  the  place,  although  possibly  a  few 
feet  of  drift  would  connect  with  other  places 
and  give  an  air-circuit.  In  Great  Britain, 
New  Zealand,  and  New  South  Wales,  where 
the  law  gives  the  inspector  some  latitude,  that 
official  would  use  his  discretion  in  deciding 
what  should  be  'adequate  ventilation  "  under 
mining  conditions.  Here  in  New  Zealand 
such  an  officer  inspects  the  mine  throughout 
frequently,  and  being  equipped  with  anemo- 
meter, hygrometer,  and  sample  bottles,  he 
quickly  settles  such  questions,  and  by  regula- 
tion he  may  constitute  any  indififerently  venti- 
lated part  of  a  mine  a  '  six  hours  place,'  that  is, 
where  six  hours  shall  be  paid  for  as  full  time, 
although  the  recognized  day  is  of  8  hours 
duration.  If  the  deadly  carbon  monoxide  in 
appreciable  quantities  appeared  in  any  part  of 
a  mine,  and  this  would  be  readily  determined 
from  the  regular  analysis  of  mine  air  taken  by 
all  Inspectors,  then  the  action  of  the  inspector 
would  be  drastic,  as  these  would  constitute  a 
breach  of  that  part  of  the  regulation  which 
specifies  that  noxious  gases  should  be  diluted 
and  rendered  harmless. 

As  regards  the  presence  of  CO  in  metal 
mines,  during  shovelling  after  blasting  no 
doubt  this  poisonous  gas  may  be  found  in 
minute  quantities  by  analysis.  Here  in  New 
Zealand  such  quantities  have  been  inappreci- 
able owing  no  doubt  to  the  almost  universal 
use  of  mechanical  ventilation,  but  in  Western 
Australia  rather  more  CO  has  been  detected. 


In  a  recent '  Report  on  Investigations  into  the 
Composition  of  the  Gases  caused  by  Blasting 
in  Mines'  by  E.  A.  Mann,  Chief  Inspector  of 
Explosives,  Western  Australia,  1911,  a  table 
is  presented  which  states  the  percentage  (by 
volume)  of  CO  in  samples  of  mine  air  taken 
during  the  shovelling  of  ground  broken  by 
blasts  of  gelignite  in  Australian  metal  mines. 
Forty  samples  were  taken  under  these  condi- 
tions, which  may  be  regarded  as  the  most 
favourable  working  conditions  for  obtaining 
good  air,  yet  the  percentage  of  CO  was 
found  to  range  from  O'OOOl  to  0'0082,  which, 
according  to  the  highest  British  authority 
(Dr.  Haldane),  is  not  productive  of  notice- 
able symptoms.  Dr.  Haldane  stated  in  his 
recent  lecture  before  the  Midland  Institute 
of  Engineers  at  Nottingham,  that  these  symp- 
toms were  never  produced  with  less  than 
0'02"o  CO,  since  absorption  ceased  when  the 
blood  became  saturated  to  a  comparatively 
slight  extent.  It  is  not  inferred  that  greater 
percentages  of  CO  may  not  be  found  in  smoke 
immediately  following  blasting,  but  men  are 
not  called  upon  to  work  in  such  an  atmosphere. 
The  object  of  my  paper  and  this  letter  is  to 
suggest  a  workable  standard  of  adequate  ven- 
tilation. 

Frank  Reed. 

Wellington,  N.Z.,  July  12. 

[We  agree  that  faulty  ventilation  may  be 
allowable  under  the  special  circumstances 
mentioned,  but  the  general  impression  given 
by  Mr.  Reed  in  the  paper  quoted  by  us  in  our 
May  issue  was  that  he  considered  the  candle 
test  good  enough,  and  that  he  objected  to  the 
academical  and  harassing  regulations  adopted 
by  various  Colonial  governments. — EDITOR.] 

Malaria. 

The  Editor : 

Sir — On  reading,  in  the  June  number  of  The 
Mining  Magazine,  your  editorial  on  malaria, 
I  was  reminded  of  a  palliative  for  mosquito 
bites,  namely  menthol,  the  use  of  which  I 
discovered  accidentally  a  short  time  ago. 

The  use  of  menthol  for  the  above  purpose 
may  be  well  known  though  I  have  never  pre- 
viously heard  of  it  in  this  connection.  There 
must  be  many  who,  like  myself,  have  suflfered 
torments  from  the  bites  of  the  various  types 
of  mosquito,  sand-fiies,  and  similar  pests  in 
places  where  the  use  of  netting  and  oil  are  not 
practicable,  and  to  any  of  these  who  have  not 
tried  the  above  remedy  the  information  I  give 
may  be  welcome. 

Stephen  J.  Lett. 

Tapianaveli,  Sumatra,  August  23. 


OCTOBER,    1911 


307 


PRECIS  OF  TECHNOLOGY 

Zinc-Dust  Precipitation — In  the  Engineering  and 
Mining  Journal  for  August  26,  C.  W.  Merrill  gives 
some  figures  obtained  from  well-known  mines,  com- 
paring the  cost  of  precipitation  of  gold  from  cyanide 
solutions  by  zinc  dust  and  zinc  shavings  respectively. 
Dust  was  tried  years  ago,  but  it  failed  to  give  satis- 
factory results,  and  was  abandoned  in  favour  of 
shavings.  Mr.  Merrill,  however,  revived  its  use  by 
inventing  suitable  apparatus,  and  his  method  is  adop- 
ted at  most  of  the  new  plants  in  North  America  ;  be- 
sides which  it  is  beginning  to  acquire  a  foothold  in 
South  Africa,  five  installations  being  now  fitted  with 
the  apparatus.  As  regards  results,  at  the  Homestake, 
in  South  Dakota,  the  zinc  consumed  in  precipitating 
exceedingly  low-grade  waste  solutions  was  0' 17  lb.  per 
ton  of  solution  with  shavings,  and  is  0'  12  lb.  with  dust . 
Throughout  the  cyanide  plant,  which  treats  altogether 
130,000  tons  of  ore  per  month,  the  consumption  of 
dust  is  01  lb.  per  ton.  At  the  new  plant  of  the  La 
Blanca,  at  Pachuca,  Mexico,  the  consumption  of  dust 
is  0'93  lb.  per  lb.  of  pure  silver  produced,  and  the  pre- 
cipitate as  taken  from  the  presses  is  73  to  75%  fine. 
At  the  new  Santa  Gertrudis  plant  in  the  same  district, 
the  consumption  is  12  lb.  per  lb.  of  silver-gold  bullion 
produced  ;  the  precipitate  is  87%  fine  and  the  bullion 
950  fine.  The  average  obtained  by  the  shaving  pro- 
cess in  Mexican  plants  is  15  lb  per  lb.  of  fine  metal, 
and  the  precipitate  is  60  to  70%.  In  the  El  Oro  dis- 
trict, in  Mexico,  there  are  three  plants,  two  using 
shavings  and  one  dust.  The  costs  of  precipitation  at 
the  first  two  are  15  and  10  cents  respectively,  while  at 
No.  3  the  cost  is  8  cents.  At  the  Goldfield  Consoli- 
dated, Nevada,  an  additional  advantage  is  gained  ;  the 
solutions  carry  much  copper  which  would  plate  and 
polarize  shavings,  but  with  dust,  owing  to  fresh  zinc 
being  continually  added,  polarization  is  prevented. 

Mr.  Merrill  proceeds  to  recapitulate  some  of  the 
advantages  of  zinc-dust  precipitation.  One  is  that 
dust  is  20%  cheaper,  a  fact  which  is  important  in  the 
treatment  of  silver  ores.  Another  is  that  the  process 
can  be  effected  out  of  contact  with  air,  thus  removing 
the  worry  caused  by  re-solution.  Thirdly,  at  each 
clean-up  the  whole  of  the  precious  metal  can  be  re- 
moved, instead  of  anything  up  to  30%  being  carried 
continuously  in  the  boxes  from  month  to  month 
Fourthly,  the  precipitate  is  collected  in  a  heavy  iron 
press,  which  acts  as  a  safe,  as  a  protection  against 
theft  and   fire. 

Tunnel  Driving. — The  Mine  and  Quarry  for  May 
contains  an  account  of  a  great  irrigation  scheme  now 
in  course  of  completion,  undertaken  for  the  purpose  ol 
collecting  water  and  carrying  it  30  miles  to  a  stretch  of 
valuable  agricultural  land  in  Strawberry  valley  near 
Utah  lake,  about  60  miles  south  of  Salt  Lake  City. 
The  great  engineering  work  in  connection  with  this 
scheme  was  the  piercing  of  an  intermediate  mountain 
range  by  means  of  a  tunnel.  The  length  of  this  tunnel 
when  completed  will  be  19,000  ft.,  and  the  fall  is  2  ft. 
per  1000.  The  higher  or  eastern  end  is  7500  ft.  above 
the  sea,  and  the  crest  of  the  mountain  range  is  1500  ft. 
above  this.  The  cross-section  of  the  tunnel  is  shown 
in  the  accompanying  illustration .  The  excavated  area 
is  about  10  ft.  high  and  9  ft.  6  in.  wide.  After  the  con- 
crete lining  is  inserted,  the  internal  width  will  be  7  ft  , 
and  the  height  to  the  crown  of  the  arch  8  ft.  6  in.  The 
depth  of  the  flowing  water  will  be  6  ft.  6  in.,  the 
volicity  will  be  12  ft.  per  second,  and  the  flow  500 cu. 
ft.  per  seconds  The  driving  was  commenced  in  1906, 
but  at  first  many  difficulties  arose,  and  work  was 
several  times  suspended.     In  the  meantime  a  hydro- 


electric power  plant  was  built,  and  in  1908  operations 
were  re-commenced  with  electric  drills.  These  were 
not  satisfactory,  and  in  1909  Sullivan  air-drills  were 
substituted.  Owing  to  the  wet  ground  at  the  eastern 
or  higher  end,  it  has  not  been  feasible  to  drive  from 
that  direction,  as  enormous  pumping  engines  would 
have  to  be  employed,  and  as  the  mountain  is  rocky  and 
precipitous,  no  shaft  could  be  sunk  from  which  to 
drive  at  an  intermediate  station,  and  it  has  therefore 
been  necessary  to  work  entirely  from  the  lower  end. 
Before  the  Sullivan  drills  started,  extensive  diamond 
drilling  was  done  with  a  view  of  ascertaining  the  nature 


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of  the  ground  through  which  the  tunnel  would  pass. 
In  actual  driving,  the  heading  and  bench  method  is 
used  Two  drills  are  employed,  and  are  mounted  on 
two  double- screw  columns  with  adjustable  arms.  After 
each  machine  has  finished  its  half  of  the  drilling  in 
the  heading  round,  it  is  turned  up  on  the  arm  and  the 
holes  for  blasting  the  bench  are  then  drilled.  Thus 
the  entire  round  of  holes  necessary  for  blasting  across 
the  tunnel  is  drilled  in  one  shift.  Usually  16  holes  are 
drilled  in  the  face  and  two  in  the  bench.  The  cut 
holes  are  7  ft.  deep  and  the  others,  including  those  in 
the  bench,  about  6  ft.  The  heading  is  driven  with  a 
bench  about  3  ft.  high,  which  is  carried  from  10  to  12 
ft  back  of  the  face.  The  holes  are  exploded  in  the 
order  shown  in  the  diagram .  The  rock  consists  of  alter- 
nate strata  of  hard  sandstone  and  hard  blue  limestone, 
the  latter  predominating.  During  the  20  months  from 
April  1909  to  November  1910,  the  tunnel  was  advanced 
7844  ft.  or  392  ft.  per  month.  The  cost  per  foot  is  esti- 
mated at  $26' 70. 


308 


THE    MINING    MAGAZINE 


Eclipse  Filter  for  Slime. — In  the  Mining  and  En- 
gineering Review  for  August,  M.  W.  Von  Bernewitz 
describes  a  new  filter  called  the  'Eclipse,'  and  in- 
vented by  H.  Wallace,  that  is  being  experimentally 
tested  at  the  Associated  Gold  Mine,  Kalgoorlie.  A 
continuous  travelling  belt  is  arranged  horizontally  and 
passes  round  rollers  at  each  end.  It  is  made  of  rubber 
punched  with  holes  and  covered  on  the  top  side  with 
filter-cloth.  It  is  3 J  ft.  wide  and  is  jointed  longitudi- 
nally along  the  middle  so  that  it  can  be  folded.  In 
the  centre  part  of  the  travel  of  the  belt  it  passes  be- 
tween a  set  of  vertical  iron  rollers  and  is  folded,  as- 
suming a  vertical  position.  The  slime  is  fed  into  the 
V-shaped  trough  of  the  belt,  and  as  the  belt  passes 
between  the  rollers  it  is  trapped,  and  squeezed  by  the 
pressure  of  the  rollers.  The  solution  is  thus  expelled 
and  caught  in  a  trough  below,  while  the  cake,  on 
emerging  from  the  end  rollers,  is  loosened  from  the 
belt  as  it  opens  flat  once  more  and  passes  round  the 
end  horizontal  roller.  The  first  vertical  rollers  are 
fiat  on  one  side  so  that  the  contained  slime  can  pass 
within  the  space  between  them  without  any  squeezing 
action.  As  the  rollers  revolve,  their  cylindrical  sur- 
faces come  opposite  each  other  and  bring  the  two 
parts  of  the  belt  into  close  contact.  Arrangements 
are  also  provided  to  keep  the  upper  edges  of  the  belt 
close  together  while  passing  along  the  space  between 
the  first,  second,  and  third  sets  of  rollers  where  the 
squeezing  takes  place.  A  machine  to  handle  650  tons 
per  day  costs  /150  to  build,  and  requires  3  horse- 
power to  drive.  It  is  claimed  that  the  continual  move- 
ment of  the  belt  prevents  the  accumulation  of  fine 
slime  in  its  interstices.  It  is  not  easy  to  describe  a 
machine  without  an  illustration  ;  unfortunately  that 
appearing  with  the  article  is  too  indistinct  for  repro- 
duction here. 

Electrostatic  Concentration  of  Zinc  Ore. — The 
Mining  and  Engineering  World  (Chicago)  for  August 
26  gives  an  account  of  the  application  of  the  Huff 
electrostatic  separator  to  the  complex  zinc  middling 
produced  at  the  Calumet  &  Sonora  Mining  Co.'s  mines 
at  Cananea,  Mexico,  not  far  from  the  Greene-Cananea 
properties.  The  mines  contain  a  mixed  sulphide  ore 
preponderating  in  galena  and  blende,  and  carrying 
varying  proportions  of  pyrite  and  chalcopyrite.  Silver 
is  associated  with  the  lead,  and  in  places  antimony  and 
bismuth  minerals  are  found.  The  gangue  consists  of 
calcite,  quartz,  and  barite.  The  chief  mine,  the 
Chivera,  is  down  545  ft.  The  first  owners  attempted 
to  recover  the  galena  by  jigging,  but  as  this  was  a  com- 
mercial failure,  the  new  owners,  advised  by  D.  E. 
Woodbridge,  consulting  engineer,  and  J.  N.  Hauser, 
superintendent,  reorganized  the  plant  and  erected 
Wilfleys  and  Deisters.  By  this  means  a  60%  lead 
concentrate  was  obtained,  with  a  middling  averaging 
30%  zinc,  ih%  lead,  7%  copper,  15%  iron,  and  3  oz. 
silver.  About  4500  tons  of  this  material  accumulated 
on  the  dump,  and  the  addition  was  15  tons  per  day. 
The  new  plant  recently  erected  for  its  treatment  con- 
sists of  10  Huff  machines  of  various  powers.  The 
middling  is  sized  to  -\-  20,  +  50,  and  -  50  A  concen- 
trate averaging  55%  zinc,  1%  copper,  and  4%  iron  is 
obtained,  with  a  recovery  of  85%  of  the  zinc.  The 
remaining  tailing  is  treated  on  tables  and  a  saleable 
copper  product  obtained. 

The  experimental  work  on  this  middling  was  done  at 
the  Huff  plant  at  Platteville,  belonging  to  the  American 
Zinc,  Lead,  and  Smelting  Co.  The  writer  of  the  article 
states  that  in  the  experiments  on  the  dump  ore  it  was 
found  that  some  of  the  copper  had  been  leached  and 
redeposited  in  a  minute  film  upon  the  blende.  This  was 
sufficient  to  give  the  blende  an  electric  characteristic 


too  much  like  that  of  the  pyrite  and  chalcopyrite,  so 
that  difficulty  was  experienced  in  getting  a  clean 
separation.  In  order  to  remove  the  copper,  the  midd- 
ling was  given  a  wash  in  weak  cyanide.  This  experi- 
ence led  the  chemists  to  apply  the  same  principle  in  a 
different  way,  namely,  to  facilitate  the  separation  of 
the  blende  from  the  gangue.  After  the  removal  of  the 
iron-copper  minerals  in  the  first  electrostatic  machines, 
it  had  been  found  impracticable  to  remove  the  gangue 
from  the  blende  by  the  Huff  process.  The  experiment 
was  therefore  tried  of  treating  the  blende  and  gangue 
with  copper  sulphate,  and  thus  to  deposit  copper  on 
the  blende.  In  this  way  the  blende  was  made  suscep- 
tible to  the  action  of  the  magnets,  and  it  could  thus  be 
separated  from  the  gangue.  More  information  on  this 
point  is  desirable. 


Section  III  rough  Cotlrell  .'^eltlrr. 

Cottrell's  Fume-Settler. — In  our  issue  of  May  last 
we  gave  a  short  notice  of  the  electrostatic  fume-settler 
erected  by  F.  C.  Cottrell  at  the  Balaklala  smelter, 
California.  The  Mining  and  Scientific  Press  for 
August  26  and  September  2  reprints  a  lengthv  paper 
on  the  subject  by  Mr.  Cottrell.  This  paper  contains 
an  interesting  and  valuable  study  of  the  philosophy 
and  applications  of  this  idea,  and  should  be  read  in 
full.  He  first  discusses  the  history  of  the  many  at- 
tempts to  remove  suspended  particles  from  gases  by 
means  of  electric  discharges,  beginning  with  Hohlfeld's 
experiments  in  connection  with  the  suppression  of  or- 
dinary smoke.  He  refers  to  the  work  in  1885  done  by 
A.  O.  Walker  and  W.  M.  Hutchingsat  Bagillt,  Flint- 
shire, where  discharges  from  Wimshurst  machines  were 
tried  for  the  purp^se  of  settling  lead  fume.  All  these 
earlier  experiments  had  the  disad\antage  of  working 
with  primitive  methods  of  obtaining  electric  discharges 
and  fields.  The  modern  high-potential  direct-current 
dynamos,  and  more  particularly  the  rectifiers  used  to 
adapt  the  current  of  alternators,  have  made  it  possible 


OCTOBER,    1911 


309 


to  conduct  experiments  on  a  much  larger  scale.  The 
principle  of  the  electrostatic  settler  may  be  explained 
in  a  few  words.  If  needle  points  connected  with  one 
side  of  a  high-potential  direct-current  line  are  brought 
opposite  a  flat  plate  connected  with  the  return  line, 
the  intervening  space  becomes  charged  with  electricity 
of  the  same  sign  as  the  points,  and  any  insulated  body 
in  this  space  is  also  charged  in  the  same  way.  If  these 
bodies  are  free  to  move,  as  in  the  case  with  dust,  fume, 
or  vapour,  they  will  be  repelled  from  the  points  toward 
the  plate  and  will  move  at  a  rate  proportional  to  its 
charge  and  the  potential  gradient  between  the  points 
and  the  plate.  If  no  solid  or  liquid  particles  are  pre- 
sent, the  same  phenomenon  is  observed  in  connection 
with  the  air  or  gas,  for  a  candle  flame  may  be  extin- 
guished by  bringing  it  near  the  points.  After  Mr. 
Cottrell  had  studied  the  problem  in  the  laboratory,  he 
tried  it  on  a  commercial  scale  at  sulphuric  acid  works 
on  San  Francisco  bay,  for  the  purpose  of  settling  the 
clouds  of  sulphuric  acid  formed  when  sulphur  trioxide 
is  brought  under  certain  conditions  in  contact  with 
water.  A  plant  of  this  sort  is  now  in  use.  The  next 
work  undertaken  was  at  the  Selby  smelter  where  an 
apparatus  was  erected  to  handle  the  corrosive  fumes 
from  the  roasters  and  refinery,  that  could  not  be  treated 


volume  varies  from  a  quarter  to  half  a  million  cubic 
feet  per  minute,  the  velocity  being  10  to  20  ft.  per 
second.  The  accompanying  Fig.  1  gives  a  plan  of 
the  arrangement  of  the  nine  precipitation  chambers, 
and  Fig.  2  a  section  through  one  of  them.  The  fans 
shown  in  Fig.  1  are  scientifically  unnecessary,  but  had  to 
be  installed  so  as  to  satisfy  the  farmers'  requirements 
as  regards  sulphur  dioxide,  the  maximum  allowed  by 
the  Courts  being  f%.  In  the  rectifier  building  the 
three-phase  current  at  2300  volts  is  stepped  up  to  25,000 
volts  and  transformed  into  an  intermittent  direct  cur- 
rent. In  Fig.  2  the  vertical  lines  represent  the  collect- 
ing or  grounded  electrodes  made  of  iron  sheets  10  ft. 
high ,  and  the  dotted  lines  show  the  discharge  electrodes 
consisting  of  two  iron-wire  strands  between  which  is 
twisted  the  asbestos  and  mica  that  form  the  discharge 
points.  The  tests  on  this  plant  showed  that  from  80 
to  90%  of  the  suspended  matter  was  precipitated  and 


E  T        FLUE 


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160 


IRO 


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in  the  bag-house.  The  refinery  gases  were  easily 
amenable  to  this  treatment,  and  by  its  means  the  sul- 
phuric acid  has  been  recovered  for  the  last  three  years. 
A  plant  was  afterwards  erected  to  treat  the  roaster 
fumes,  and  its  operation  satisfactorily  determined,  but 
owing  to  the  fume  litigation  the  further  refitting  and 
introduction  of  practical  modifications  has  been  sus- 
pended. The  experience  gained  at  these  two  works 
was  applied  to  the  erection  in  March  1910  of  a  larger 
plant  to  treat  the  whole  of  the  gases  at  the  Balaklala 
copper  smelter  at  Coram,  California.  This  gave  en- 
couraging results,  but  did  not  remove  a  large  enough 
proportion  of  the  fume  and  gases  to  appease  the  farmers 
and  the  Courts,  so  it  has  for  the  present  gone  out  of  use 
and  the  smelter  is  closed.  A  detailed  description  of 
the  plant  will  nevertheless  be  of  value.  The  capacity 
of  the  smelter  is  700  to  1000  tons  per  day,  and  the  ore 
averages  2\  to  3%  copper.  Most  of  the  ore  goes  to 
the  blast-furnaces,  and  the  remainder  to  McDougal 
roasters  and  a  reverberatory  furnace.  There  is  also  a 
converter  installation.  The  gases  from  all  these  fur- 
naces go  to  a  flue  measuring  18  by  20  ft.,  and  their 


P]an  of  Cottri-ll   Plnnf  at  BfiUiklnln. 

that  from  8  to  10  tons  of  fume  was  caught  per  24  hours. 
The  tests  made  for  the  Courts  showed  an  average  pre- 
cipitation of  72'8%.  The  cost  of  the  installation  was 
1110,000,  and  the  power  required  for  the  current  is  120 
kilowatts.  One  of  the  chief  difficulties  to  be  contended 
with  in  this  process  is  the  loss  of  conductivity  of  the 
mica  and  asbestos  points.  Moisture  from  the  air  ac- 
cumulates on  them,  and  in  addition  the  zinc  oxide  in 
the  fume  is  inimical  to  their  conductivity.  The  author 
promises  on  a  future  occasion  to  tell  more  about  the 
methods  employed  to  preserve  the  conductivity. 

Tin  in  Rhodesia. — Several  discoveries  of  tin  ore 
have  been  made  in  Rhodesia  during  the  last  year  or 
two.  We  have  already  published  descriptions  of  the 
occurrences  in  the  Enterprise  and  Abercorn  districts. 
In  the  Rhodesian  Mining  Revieu'  for  .August  16, 
R.  C.  H.  Cooke  describes  the  deposits  quite  recently 
discovered  near  Ndanga,  42  miles  east  of  Victoria, 
which  is  150  miles  due  east  of  Bulavayo.  The  forma- 
tion carrying  the  tin-bearing  dikes  is  a  belt  of  dark 
close-grained  epidiorite,  running  east  and  west,  about 
4  miles  from  a  granite  contact  on  the  north  and  6  miles 
from  a  similar  contact  on  the  south.  Banded  iron- 
stone and  schists  are  found  in  the  intervening  spaces, 
the  latter  being  nearest  the  granite.  The  epidiorite 
shows  fissures,  filled  by  pegmatite  dikes  that  have  sub- 
sequently become  greisenized.  Mr.  Cooke  describes 
three  of  these  dikes.  Two  strike  across  the  formation 
and  a  third  is  parallel  with  it.     The  dike  farthest  west 


310 


THE    MINING    MAGAZINE 


is  wide  and  is  composed  of  a  characteristic  greisen  con- 
taining lepidolite-mica,  but  does  not,  so  far  as  pro- 
spected, show  any  tin.  The  next  dike  200  ft.  east  has 
been  followed  for  1000  yards  and  varies  from  10  to  20 
ft.  wide.  It  carries  visible  cassiterite  over  almost  its 
entire  outcrop,  and  in  some  places  samples  assayed 
10%  tin.  It  consists  mainly  of  quartz  with  white  and 
pale  green  mica,  sericite  and  muscovite,  and  here  and 
there  hexagonal  prisms  of  brown  tourmaline.  The 
cassiterite  occurs  in  all  sizes  from  minute  particles  to 
crystals  an  inch  long.  The  dike  has  weathered  well 
and  stands  prominently  above  the  adjoining  country 
in  some  places.  The  third  dike  cuts  across  No.  2  at 
its  northerly  end  and  is  of  similar  constitution  except 
that  it  contains  no  muscovite.  Sampling  gave  over 
2%  tin.  There  is  reason  to  believe  that  other  tin- 
bearing  dikes  will  be  found,  for  one  river-bed  con- 
tains water-worn  crystals  of  cassiterite  that  could  not 
have  originally  come  from  those  already  known.  No 
work  has  yet  been  done  to  prove  the  nature  of  the 
dikes  in  depth. 

Johnson's  Electric  Zinc  Furnace. — At  the  meeting 
of  the  American  Electrochemical  Society  held  in  April, 
Joseph  W,  Richards  read  a  paper  describing  an  elec- 
tric furnace,  designed  by  W.  Mc  A.  Johnson,  for  dis- 
tilling zinc  ores.  The  furnace  on  which  the  experi- 
mental work  was  done  absorbed  25  kilowatts,  and  the 
results  were  so  good  that  a  larger  one  is  now  being 
built.  Owing  to  the  interest  aroused  in  England  by 
the  purchase  of  the  Swedish  and  Norwegian  smelting 
works,  as  described  in  another  paragraph  in  this 
'  Precis,'  we  reproduce  the  illustration  of  Mr.  John- 
son's furnace  and  quote  Professor  Richards'  article. 
It  will  be  seen  that  there  are  two  movable  positive 
electrodes,  and  one  negative  electrode  embedded  in 
the  bottom  of  the  furnace.  The  feed  is  continuous, 
the  ore  being  introduced  between  the  two  positive 
electrodes.     The  heat  is  generated  by  the  resistance 


rr-r— TT 


Johnson's  Electric  Zinc  Furnace. 

of  the  charge,  and  the  current  is  so  regulated  that  the 
temperature  of  the  slag  shall  be  1250°  to  1300° C,  and 
that  the  escaping  gases  on  arriving  at  the  condenser 
shall  be  about  850°  C.  Between  the  furnace  and  the 
condenser  is  interposed  a  column  of  coke  that  is  kept 
incandescent  by  means  of  an  electric  current.  The 
function  of  this  is  to  reduce  the  carbonic  acid  in  the 
gases  to  carbonic  oxide,  and  in  this  way  to  prevent  the 
formation  of  fume  as  much  as  possible.  The  zinc 
vapour  and  carbonic  oxide  are  then  made  to  impinge 
on  liquid  zinc  in  the  condenser.  When  treating  an 
ore  containing  lead,  the  latter  is  reduced  and  collects 
as  bullion  that  can  be  tapped,  while  iron  and  copper 
with  any  sulphur  will  form  a  matte,  just  as  in  a  lead- 
smelting  furnace.  The  condition  of  the  furnace  is 
such  that  the  reducing  action  is  strong  enough  to  distil 
the  zinc,  but  not  to  reduce  any  appreciable  amount  of 
iron  in  the  slag.  Mr.  Richards  states  that,  in  this 
small  furnace,   when  treating  fairly  clean   zinc  ores, 


and  when  recovering  75%  of  the  zinc  in  liquid  form, 
two  tons  of  metal  can  be  produced  per  horsepower- 
year.  In  this  furnace  the  general  physical  conditions 
of  the  ore  must  be  much  the  same  as  in  the  present 
retort  practice  ;  that  is  to  say,  there  must  be  little 
gangue,  and  the  sulphur  must  be  roasted  and  the 
carbonates  calcined. 

Electric  Smelting  of  Zinc-Lead  Ores. — It  has  else- 
where been  announced  that  an  English  company  has 
been  formed  for  the  purpose  of  acquiring  two  electric 
smelting  works,  one  at  Sarpsborg,  Norway,  and  one  at 
TroUhattan,  Sweden,  and  also  the  rights  in  connection 
with  the  construction  of  another  at  Tysse,  near  Odde, 
in  Norwav.  The  process  and  furnace  used  at  these 
works  are  intended  for  the  treatment  of  complex  sul- 
phide ores,  and  other  material  such  as  Broken  Hill 
slime,  and  the  intimately  mixed  sulphides  of  lead,  zinc, 
copper,  and  iron  that  occur  in  large  quantities  in  various 
parts  of  the  world,  at  present  of  little  or  no  commercial 
value.  Reports  have  been  made  by  J.  C.  Moulden  for 
the  Sulphide  Corporation,  and  by  F.  W.  Harbord,  the 
latter  of  whom  made  thorough  tests  of  the  plants  at 
Sarpsborg  and  TroUhattan.  We  cull  the  information 
here  given  from  the  reports  of  these  experts.  The 
electric  furnace  employed  has  carbon  electrodes,  and 
the  heating  and  melting  of  the  charge  is  effected  by 
resistance  with  a  current  of  low  voltage.  One  elec- 
trode is  in  the  bed,  and  the  upper  one  is  removable 
through  the  roof.  The  cross-section  of  the  upper  elec- 
trode measures  approximately  2^  sq  ft.  In  the  first 
furnaces  the  charge  was  introduced  through  the  roof, 
but  more  recently  the  door  is  placed  in  the  side  and 
the  operation  is  thus  made  more  continuous.  The 
capacity  is  3  tons,  and  28  tons  of  roasted  ore  can  be 
treated  per  24  hours.  The  horse-power  per  furnace  is 
350,  and  at  TroUhattan  the  cost  of  power  supplied  by 
the  hydro-electric  company  is  30s.  3d.  per  horsepower- 
year.  At  Mr.  Harbord's  tests  on  roasted  Broken  Hill 
slime,  the  energy  used  per  ton  of  ore  was  2078  kilowatt- 
hours.  There  are  11  furnaces  at  TroUhattan.  The 
roasted  ore,  coke  or  anthracite  dust,  and  flux  are 
charged  into  the  furnace,  and  most  of  the  zinc  and 
some  of  the  lead  is  volatilized.  The  greater  propor- 
tion of  this  is  condensed  as  a  crude  spelter  with  high 
lead  content,  but  much  of  it  is  precipitated  as  metallic 
fume  and  oxide,  and  has  to  be  returned  to  the  furnace 
in  subsequent  charges.  The  lead  that  is  not  volatilized 
is  reduced  as  liquid  metal,  and  it  contains  a  consider- 
able proportion  of  the  silver.  Matte  is  formed  of  the 
iron,  copper,  and  sulphur,  if  present  in  the  ore,  and 
some  of  the  lead,  zinc,  and  silver  passes  into  it.  Some 
lead  also  escapes  with  the  slag.  The  crude  zinc  is  re- 
fined in  other  electric  furnaces  and  the  final  zinc  pro- 
duct is  exceptionally  pure,  averaging  99  9%,  and  com- 
manding a  premium  price  in  the  market.  At  the  time 
Mr.  Harbord  made  his  examination,  the  furnaces  were 
built  of  porous  material,  apparently  similar  to  that  used 
in  old-fashioned  zinc-distilling  retorts,  and  some  of  the 
lead  and  silver  percolated  through  and  had  to  be  caught 
underneath  ;  this  he  calls  '  leakage  '  lead.  He  found 
also  that  the  lead  that  exuded  in  this  way  during  his 
experiments  did  not  necessarily  come  from  the  charges 
under  his  observation,  and  was  partly  produced  during 
the  treatment  of  other  ore  at  an  earlier  period.  Thus 
the  silver  contents  of  the  lead  did  not  at  all  coincide 
with  that  of  the  ore  treated  by  him.  The  general  re- 
sults of  his  trials  were  by  no  means  ideal,  and  he  makes 
many  suggestions  for  improvements  ;  but  his  conclu- 
sions are  that  the  process  may  easily  be  developed  into 
one  of  prime  importance,  especially  at  the  new  plant 
proposed  at  Tysse,  where  the  estimated  cost  of  a  horse- 
power-year is  only  14  shillings.   During  his  experiments 


OCTOBER,    1911 


311 


at  Trollhattan,  seven  furnaces  treated,  during  27J  days, 
518  tons  of  roasted  Broken  Hill  slime,  19  tons  of  cala- 
mine, 21^  tons  of  zinc-lead  powder  produced  previously, 
and  produced  160  8  tons  of  crude  zinc  whicti  by  refin- 
ing yielded  1124  tons  of  pure  zinc  and  247  tons  of  lead, 
together  with  36  tons  of  powder  ;  in  addition  to  which 
41  tons  of  lead  was  tapped  containing  141  oz  silver  per 
ton,  and  'leak  '  lead  amounting  to  17  tons  was  recovered 
assaying  27  oz.  silver  per  ton,  also  9  tons  of  skimmings 
containing  zinc,  lead,  and  silver.  The  recovery  from 
these  various  sources  was  64%  of  the  zinc,  74%  of  the 
lead,  and  46%  of  the  silver,  not  reckoning  the  metals 
recovered  in  the  powder  form.     Mr.  Harbord  goes  into 


Southern  Norway,  shou'ing  Position  of  Hydro- Electric  Zinc-Smelting  Plants 

details  as  to  many  points  where  increased  extraction 
and  lower  costs  may  be  obtained.  Mr.  Moulden  is  of 
opinion  that,  by  means  of  improvements  already  indi- 
cated, the  extraction  should  eventually  be  75%  of  the 
zinc,  80?.^  of  the  lead,  and  80%  of  the  silver,  and  on 
this  basis  he  figures  the  profit  obtainable  on  slime 
bought  from  the  Sulphide  Corporation  and  shipped  to 
Sweden.  This  slime  is  taken  to  average  32%  zinc,  23% 
lead,  and  25  oz.  silver,  and  on  the  current  basis  of  pay- 
ment would  cost  £2.  16s.  8d.  per  ton  at  Broken  Hill. 
The  freight  to  Trollhattan  would  be /2.  5s.  3d.,  making 
the  total  cost  per  ton  at  the  smelter  {5.  8s.  5d.  The 
value  of  the  recovered  metals  on  the  percentage  figured 
by  Mr.  Moulden  would  be  £9.  9s.  lid.  The  cost  of 
treatment  he  estimates  at  /3.  Os.  7d.,  so  that  the  mar- 


gin of  profit  would  be  £l.  9s.  per  ton  of  slime.  It  is 
unnecessary  to  say  that  the  process  is  in  its  infancy,  and 
that  many  improvements  are  already  obvious ;  also  that 
everything  dependsonthecostof  electricheat.  Enough 
is  shown,  however,  in  these  reports  to  make  it  clear 
that  the  process  and  method  of  metallurgy  deserve 
close  attention. 

Ore-Shoots  at  Pachuca. — In  Economic  Geology 
for  August,  Fred  J.  I'ope  contributes  a  paper  on  the 
ore-shoots  in  the  Pachuca  district,  Mexico.  He  shows 
that  their  occurrence  is  associated  with  certain  charac- 
teristics of  the  country  rock,  characteristics  which  are 
the  result  of  magmatic  difterentiation.  Owing  to  the 
,2  terms  of  professional  engagements,  he 

is  not  at  liberty  to  describe  the  ore- 
shoots  in  detail,  nor  to  specify  the 
names  of  the  particular  mines  where 
he  studied  the  question  ;  but  we  know 
that  the  Santa  Gertrudis  is  one  of  them, 
and  that  his  deductions  had  important 
influence  in  the  calculations  of  re- 
serves. The  sedimentary  rocks  in  the 
district  are  Tertiary,  and  the  silver- 
bearing  veins  are  found  in  dome- 
shaped  intrusions  of  andesite-porphyry . 
A  study  of  the  rocks  shows  that,  after 
these  intrusions,  there  were  others  of 
andesite  and  of  rhyolite  with  interme- 
diate erosions,  and,  later,  intrusions  of 
quartz-porphyry  dikes  that  cut  through 
all  the  andesites.  Then  followed  a 
period  of  faulting,  and  the  silicification 
of  the  fissures.  Up  to  this  time  no 
mineral  of  economic  value  had  made 
its  appearance,  but  subsequently  there 
was  a  second  period  of  faulting,  gener- 
ally along  the  same  fissures,  during 
which  the  argentite  was  deposited  in 
the  fracture- fissures  of  the  andesite- 
porphyry  domes.  This  andesite-por- 
phyry exhibits  variations  in  its  con- 
stitution. Most  of  it  is  of  light  grey- 
green  colour  and  averages  65%  silica, 
but  other  parts  are  dark  reddish-brown 
and  dark  green,  with  not  more  than 
60%  silica,  and  also  much  tougher. 
There  is  no  sharp  dividing  line  be- 
tween the  two  varieties.  The  basic 
rock  occurs  irregularly  throughout  the 
lighter  rock,  and  is  usually  in  the  form 
of  lenticular  masses.  By  experience 
the  basic  rock  has  been  found  unfav- 
ourable to  the  presence  of  ore. 

The  veins  are  not  simple  fissures,  but 
rather  crushed  zones  varying  from  a  few 
feet  to  40  or  50ft.  in  width.  In  some 
places  the  hanging  wall  and  foot-wall 
areclearly  defined  ;  more  often  there  is  no  dividing  line, 
and  the  limits  of  economic  ore  can  only  be  determined 
by  sampling.  After  the  first  faulting,  the  solutions 
filled  the  interstices  with  silica  and  also  attacked  some 
of  the  brecciated  rock  metasomatically.  In  this  tank- 
ing, the  crushing  of  the  softer  and  more  acid  rock 
would  be  more  extensive  and  complete  than  that  of 
the  tougher  and  more  basic,  and  larger  cavities  would 
be  formed.  The  silica  deposited  would  be  more  triable 
and  more  replacement  would  take  place.  With  the 
tougher  rock  the  silica  deposited  by  replacement  would 
be  hornv  and  harder  even  than  much  of  the  country 
rock.  Considering  all  these  circumstances,  when  the 
second  faulting  took  place,  the  shattering  would  be 
greatest  in  the  softer  veins  contained  in  the  acid  por- 


4—6 


312 


THE     MINING     MAGAZINE 


tions  of  the  rock,  and  the  mineralizing  solutions  that 
afterwards  flowed  upward  would  pass  along  these 
opened  channels.  In  this  way  the  mineral  veins 
would  be  formed  in  the  acid  portions  of  the  andesite- 
porphyry  rock.  As  regards  the  original  formation 
of  this  rock,  Mr.  Pope  shows  that  the  basic  portions 
could  not  have  been  formed  separately  at  different 
times,  but  were  undoubtedly  due  to  magmatic  differ- 
entiation during  the  cooling  of  one  flow. 

Kemoving  Oil  from  Return  Feed- Water. — In  the 
Monthly  Journal  of  the  West  Australian  Chamber  of 
Mines,  C.  E.  Crocker  gives  an  account  of  a  plant  used 
at  the  Kalgoorlie  Electric  Power  &  Lighting  Co.'s 
works,  for  reducing  the  amount  of  oil  in  the  water 
that  comes  from  the  condensers,  before  returning  the 
water  to  the  boiler-feed.  Oil  is  destructive  to  boiler 
plates  and  tubes,  and  a  thin  film  upon  the  inside  will 
retard  the  transmission  of  heat  as  much  as  Jin.  of 
scale.  Most  of  the  oil  can  be  removed  by  skimming, 
and  it  is  only  that  which  has  been  made  into  an  emul- 
sion by  the  action  of  steam  that  causes  difficulty. 
Many  different  methods  were  tried,  and  finally  coagu- 
lation with  alum  and  soda  was  adopted,  as  being 
cheapest  and  most  effective.  The  author  does  not 
claim  this  method  as  new,  but  considers  that  his  ex- 
perience will  be  useful  to  mining  engineers  in  out-of- 
the-way  places.  The  water  contains  3  5  grains  of  oil 
per  gallon,  and  after  treatment  085  grains.  The  cost 
of  chemicals  is  llSd.  per  1000  gallons;  035  lb.  of 
alum  and  03  lb.  of  soda  are  used  per  1000  gal.  In 
the  Kalgoorlie  plant,  50,000  gal.  of  water  is  treated 
per  24  hours.  The  two  chemicals  are  dissolved  in 
separate  tanks  and  the  solutions  allowed  to  drop  into 
a  long,  shallow,  mixing  tank  through  which  the  oily 
water  runs.  The  mixture  is  then  delivered  to  a  second 
mixing  tank  of  similar  shape.  Both  tanks  have  baffle 
boards,  over  and  under  which  the  water  flows,  and  the 
second  tank,  towards  the  discharge  end,  contains  rough 
filtering  material  such  as  firewood.  The  water  then 
runs  to  a  series  of  filter  drums  of  upright  cylindrical 
shape.  These  contain  horizontal  perforated  trays 
about  half-way  down,  on  which  is  placed  filtering  ma- 
terial such  as  coke,  wood-wool,  or  shavings.  Sand  is 
not  suitable  as  it  clogs  too  soon.  The  precipitate  is 
light  and  easily  broken,  so  no  eddies  or  agitation  must 
be  allowed.  The  capacity  of  the  tanks  and  filters  is 
such  that  five  hours  are  occupied  in  the  passage  of  the 
water.  Mr.  Crocker  is  of  opinion  that  a  longer  time 
would  be  advantageous,  as  it  vvould  give  a  better  ex- 
traction and  a  less  consumption  of  chemicals. 

Zinc  Oxide. — The  Engincerins  and  Mining  Jour- 
nal for  September  23  describes  a  process  invented  by 
Abraham  Blum  of  Monterey,  Mexico,  for  the  produc- 
tion of  zinc  oxide  from  low  grade  ores,  and  slags  and 
other  residues.  It  is  a  modification  of  the  Wetherill 
process,  and  consists  of  the  use  of  a  Huntington  - 
Heberleinpot.  The  Wetherill  process  has  been  used 
for  many  years  in  New  Jersey  and  Pennsylvania.  The 
zinc-bearing  material  is  calcined  or  roasted,  mixed 
with  powdered  coal,  spread  on  a  reverberatory,  and 
exposed  to  a  low  -  pressure  blast  coming  upward 
through  perforations.  The  zinc  is  distilled  and  is 
immediately  oxidized  and  collected  as  zinc  white.  In 
Mr.  Blum's  invention  the  reverberatory  is  displaced 
by  a  pot.  By  this  means  several  layers  of  ore  and 
coal  can  be  placed  on  the  hearth,  and  a  much  higher 
pressure  can  be  used.  Thus  the  rate  of  treatment  can 
be  greatly  increased  and  the  cost  of  labour  lessened. 
The  ore  that  he  has  been  treating  is  the  low  grade 
fine  from  Minas  Vejas.  This  contains,  before  roast- 
ing, 23%  zinc  and  23%  iron,  and  is  free  from  lead  and 
arsenic.      The  oxide  obtained  assayed   765%    zinc. 


With  ores  containing  lead,  the  product  would  be  a 
white  zinc-lead  pigment.  The  Wetherill  process  is 
restricted  as  to  temperature  by  the  formation  of  liquid 
slag  which  stops  up  the  perforations  in  the  grate  ; 
but  in  the  pot  used  by  Mr.  Blum  a  fairly  porous  sinter 
is  obtained  which  does  not  interfere  with  the  blast  and 
can  be  readily  discharged.  The  blast  can  be  so  regu- 
lated that  no  iron  goes  over  with  the  zinc,  and  thus 
the  yellow  or  brown  stain  is  obviated  ;  also  the  heat 
is  such  that  the  zinc  oxide  is  not  crystallized,  but 
passes  over  as  impalpable  powder.  The  conical  pot 
used  by  Mr.  Blum  is  12  metres  wide  and  1  metre 
deep,  and  the  charge  consists  of  120  Kg.  1  of  coal  and 
120  Kg.  1  of  ore.  The  bottom  layer  is  of  coal,  then  a 
layer  of  ore  and  coal,  then  a  layer  of  coal,  and  so  on. 
After  ignition,  the  blast  is  introduced  below  the  grate, 
first  at  a  pressure  of  2  in.,  and  then  gradually  increas- 
ing to  12  in.  In  half  an  hour  a  good  reaction  com- 
mences, and  it  is  completed  in  6  hours.  Mr.  Blum 
considers  it  possible  to  use  a  larger  pot,  bowl-shaped, 
210  metres  in  diameter  at  the  top  and  I  metre  deep. 
This  would  treat  a  charge  of  3  tons,  and  3  charges 
could  be  worked  in  a  day. 

Continuous  Cyanidation. — In  our  August  issue  we 
quoted  in  our  '  Current  Literature  '  column  an  article 
by  John  E.  Rothwell  advocating  the  adoption  of  pulp- 
thickeners  in  the  cyanidation  of  slime,  and  the  treat- 
ment of  the  slime  in  stages,  using  the  strongest  solu- 
tion last  and  working  the  solution  from  vat  to  vat  in 
the  opposite  direction  to  the  flow  of  the  pulp.  The 
article  appeared  in  the  July  issue  of  Chemical  and 
Metallurgical  Engineering.  Mr.  Rothwell  returns  to 
the  subject  in  the  September  issue  of  the  same  paper, 
and  describes  a  proposed  installation  adapting  his 
ideas.  Though  this  article  is  not  a  record  of  results, 
it  contains  matter  of  interest.  In  the  usual  cyanide 
process,  the  strong  barren  solution  is  used  at  the  be- 
ginning of  operations,  and  the  rate  of  solution  of  the 
gold  and  silver  decreases  as  the  metals  are  taken  up  ; 
consequently  anything  like  a  complete  extraction  takes 
a  prolonged  period.  In  some  cases  it  is  necessary  to 
introduce  fresh  solution,  not  necessarily  barren,  in 
order  to  continue  the  extraction.  According  to  the 
author's  method,  the  solvent  lowest  in  metal  content 
and  highest  in  free  cyanide  is  applied  to  the  ore  after 
the  greater  proportion  of  metal  has  been  dissolved. 
After  treatment,  this  solution  is  separated  by  means  of 
a  pulp-thickener  and  delivered  to  another  agitator  vat 
to  treat  richer  ore,  and  so  on  to  the  vat  where  solution 
weakest  in  cyanide  and  richest  in  metal  attacks  the 
slime  as  it  comes  from  the  grinding  machines.  Thus 
the  installationconsistsofalternatepulp-thickenersand 
agitator  vats,  the  solution  removed  by  each  thickener 
going  to  the  previous  vat  and  the  pulp  passing  to  the 
next  one.  The  accompanying  flow-sheet  explains  the 
method  at  a  glance.  The  pulp  from  the  grinding-mill 
(where  cyanide  is  used;  is  dewatered  in  (/)  and  sent  to 
agitator  (2)  where  it  is  treated  with  solution  removed 
by  the  thickener  (5).  After  treatment,  the  pulp  is 
thickened  in  (J)  and  passes  to  agitator  (4),  where  it  is 
treated  with  solution  from  thickener  (7).  Subsequently 
it  goes  to  thickener  (5)  and  on  to  agitator  (6).  where  it 
is  treated  with  solution  from  thickener  (8).  The  pulp 
is  then  dewatered  in  (7)  and  goes  to  thickener  (5),  along 
with  barren  solution  from  {11)  and  sufficient  water  to 
make  up  waste.  The  overflow  from  (S)  goes  to  agitator 
(6)  and  the  surplus  to  the  grinding-mill.  The  pulp 
discharged  from  {R)  may  be  filtered  or  sent  to  waste 
according  to  the  amount  of  cyanide  solution  worth  re- 
covering. Our  readers  will  see  that  Mr.  Rothwell's 
scheme  is  an  ingenious  modification  of  the  recent 
application  of  the  Dorr  thickener 


OCTOBER,    1911 


313 


Co,,„rer.  iTcryen/-  /nemoaf 


CONTINUOUS    CYANIDATION. 


CURRENT    LITERATURE. 

Reversing  Ventilation.— In  the  Colliery  Gxiardian 
for  July  28  and  August  4,  18,  and  25,  T.  A.  Southern 
and  H.  W.  Halbaum  discuss  the  principles  involved 
m  reversing  the  ventilation  in  coal  mines.  This  sub- 
ject IS  now  receiving  much  attention  owing  to  the  pro- 
posal of  the  Government  to  makeVeversible  ventilation 
compulsorv. 

Hectric  Hoisting.— The  Engineering  and  Mining 
Journal  for  August  26  contains  a  description  of  the 
electric  wmdmg  engine  at  the  Ray  copper  mine. 
Arizona.  An  alternating  current  is  generated  19  miles 
away  and  transmitted  at  40,000  volts.  This  is  trans- 
formed at  the  mine,  and  the  motor  driving  the  wind- 
ing engine  is  operated  at  440  volts.  The  motor  runs 
continuously  and  is  connected  by  ropes  to  the  hoist- 
ing drums,  which  are  brought  into  operation  as  de- 
sired by  means  of  friction  clutches. 

Coaldust  in  Mines.— At  the  Cardiff  meeting  of  the 
Institution  of  Mining  Engineers  held  last  month,  Sam 
Mavor  read  a  paper  reviewing  the  various  soHrces  of 
the  dust  that  accumulates  in  coal  mines,  together  with 
the  methods  proposed  for  preventing  its  settlement 
for  effecting  its  removal,  or  for  making  it  less  liable  to 
e.xplosion.      He  also  described  the  Hawa  collector 

Weighing  Ore  on  Travelling  Belts.— In  the  En- 
gineering and  Mining  Journal,  E.  H.  Messiter  de- 
scribes an  electric  apparatus  for  weighing  ore  during 
its  transport  on  a  travelling  belt.  The  momentary 
variations  in  weight  as  the  belt  passes  a  certain  point 
are  made  to  affect  the  resistance  of  an  electric  circuit. 
Caving  at  Scranton.— In  the  September  Bulletin 
of  the  American  Institute  of  Mining  Engineers,  Eli  T 
Conner  describes  the  workings  of  the  coal  seams  under 
the  town  of  Scranton,  Pennsylvania,  and  discusses 
methods  of  supporting  the  roofs  by  flushing  sand  or 
culm,  so  preventing  a  recurrence  of  the  caving  that  has 
alarmed  the  community  on  more  than  one  occasion. 

Mining  at  Melones.  —  In  the  Engineering  and 
Mining  Journal  for  September  16,  W.  G.  Devereux 
describes  the  method  of  mining  adopted  at  the  Melones 
mine,  in  the  mother  lode  of  California.  This  article 
will  be  read  with  interest  in  conjunction  with  one  by 
F.  Langford  on  the  adaptation  of  this  method  at 
Braden,  Chile,  that  will  appear  in  our  next  issue. 

Mining  at  Crystal  Falls. — The  Mining  and  Scien- 
tific Press  for  September  2  contains  an  article  by 
F.  C.  Roberts,  describing  the  method  of  block-cavin" 
and  sub  stoping  at  the  Tobin  mine.  Crystal  Falls'! 
Michigan. 

Valuing  Mines. — In  the  Mining  and  Scientific 
Press  for  September  16,  Morton  Webber  writes  on 
'  estimating  and  valuing  the  future  of  mines  ';  he  dis- 
cusses the  chances  of  the  prolongation  of  ore-shoots 
and  the  degree  to  which  such  a  prolongation  mav  be 
assumed  when  estimating  the  eventual  life  of  a  mine. 
Brakpan. — The  South  African  Mining  Journal 
for  August  12  contains  a  full  description  of  the  metal- 
lurgical plant  now  at  work  at  the  Brakpan  mine  in  the 
far  east  Rand. 

McKesson  Sizer. — Mining  Science  for  September 
14  describes  an  apparatus,  somewhat  like  a  concen- 
trating table,  used  for  sizing  ore  without  screen  or 
water. 

Cyaniding  Concentrate. — At  the  July  meeting  of 
the  Chemical,  Metallurgical,  and  Mining  Society  of 
South  Africa,  R.  Lindsay  read  a  paper  describing'  the 
method  adopted  at  the  Geldenhuis  Deep  for  treating 
the  pyritic  material  that  accumulates  on  the  amalga- 
mation plates.  The  material  is  scraped  off  every  day, 
ground  in  barrels,  and  cleaned  by  being  passed  over 


314 


THE     MINING     MAGAZINE 


other  plates.  It  is  then  all-shmed  in  a  tube-mill,  and 
cyanided  by  the  method  devised  by  A.  F.  Crosse  some 
years  ago  and  already  described. 

Treatment  of  Accumulated  Slime. — At  the  July 
meeting  of  the  Chemical,  Metallurgical,  and  Mining 
Society  of  South  Africa,  J.  E.  R.  Adendorff  read  a 
paper  describing  experiments  undertaken  to  ascertain 
the  best  method  of  treating  accumulated  slime  contain- 
ing acid  by  means  of  air-lift  agitation. 

Sizing  for  Amalgamation. — In  the  Canadian  Min- 
ing Journal  for  September  15,  P.  N.  Nissen  advocates 
a  plan  for  improving  amalgamation  by  sizing  the  pulp 
and  having  plates  specially  adapted  for  each  size. 

Fine  Gold  in  Placers.  —  F.  H  Hazard,  in  the 
Engineering  and  Mining  Journal  of  August  26,  dis- 
cusses the  necessity  for  evolving  apparatus  for  catch- 
ing fine  gold  and  '  black-sand  '  contained  in  gravel, 
and  describes  a  plant  used  at  the  Old  Channel  placer 
mine,  Oregon. 

Electric  Tin  Smelting.  —  In  Metallurgical  and 
CJiemical  Engineering  for  September,  John  Harden, 
of  the  Grondal-Kjellin  Co.,  describes  experiments 
made  at  St.  Ives  last  year  on  the  smelting  of  tin  ores 
in  the  electric  furnace. 

Colorado  Zinc  Ore. — In  the  Engineering  and  Min- 
ing Journal  for  August  26,  George  O.  Argall  de- 
scribes the  present  mining  operations  at  Leadville, 
undertaken  for  the  purpose  of  winning  the  carbonate 
and  silicate  of  zinc,  left  behind  in  the  mines  in  earlier 
days,  when  only  lead  ores  were  considered. 

Lead  Assay. —  In  the  Engineering  and  Mining 
Journal  for  August  26,  R.  T.  Wilder  describes  a 
modification  in  Low's  bichromate-iodide  method  of 
estimating  lead  in  ores. 

Tin  Assay. — The  Report  of  the  Inspector  of  Alkali 
Works  for  1910  contains  an  article  on  the  estimation 
of  total  and  volatile  sulphur  in  tin  ores  by  S.  E. 
Linder. 

Iron  Ore  in  New  Zealand. — In  the  Mining  and 
Engineering  Review  for  August,  S.  Irwin  Crookes 
describes  the  iron  ore  deposits  at  Parapara  at  the 
northern  end  of  the  south  island  of  New  Zealand. 
These  deposits  have  already  formed  the  subject  of 
papers  prepared  by  the  geological  survey,  and  are  con- 
sidered to  be  the  most  important  in  New  Zealand  or 
Australia.  Mr.  Crookes  gives  a  dissertation  as  to 
their  present  economic  value. 

Evans-Stansfield  Electric  Steel. —  The  Canadian 
Mining  Journal  for  September  15  gives  a  short  notice 
of  an  electric  steel  process  whereby  high-class  titanium 
tool-steel  can  be  obtained  direct  from  titaniferous  iron 
ores,  invented  by  J.  W.  Evans  and  Alfred  Stansfield, 
and  recently  shown  at  the  Canadian  National  Exhibi- 
tion at  Toronto. 

TroUhattan  Hydro-electric  Power. —  Engineering 
for  September  22  contains  an  article  giving  full  par- 
ticulars of  the  hydro-electric  power  station  at  TroU- 
hattan, Sweden.  This  is  of  particular  interest  at  the 
present  time,  as  will  be  seen  by  reference  to  an  article 
in  our  Precis,  on  the  application  of  this  electric  cur- 
rent to  the  smelting  of  complex  sulphides. 

Conversion  Factors  for  Cost  of  Power. — Metallur- 
gical and  Chetnical  Engineering  for  September  pub- 
lishes tables  calculated  by  Carl  Hering  giving  conver- 
sion factors  useful  in  connection  with  costs  of  electric 
power,  such  as  £  per  horse-power-year  and  cents 
per  kilowatt-hour. 

Copies  of  the  original  papers  and  articles  men 
tioned  under  '  Precis  of  Technology  '  and  '  Current 
Literature  '  can  be  supplied  on  application  to  The 
Mining  Magazine. 


BOOKS  REVIEWED 

The  Mineral  Industry  :  Its  Statistics,  Tech- 
nology, AND  Trade,  during  1910.  Edited  by 
Albert  Hill  Fay.  New  York  :  The  McGraw-Hill 
Book  Co.  For  sale  by  The  Mining  Magazine. 
Price  42s. 

Last  year  in  reviewing  the  eighteenth  yearly  issue 
of  this  great  reference  book,  founded  by  the  late 
Richard  P.  Roth  well,  we  expressed  regret  that  the 
owners  of  the  Engineering  and  Mining  Journal  had 
disposed  of  the  book  to  another  firm  of  publishers  and 
that  W.  R.  Ingalls  was  no  longer  to  be  editor.  We 
indeed  feared  that  the  publication  would  lose  most  of 
its  glory,  so  we  are  all  the  more  gratified  to  find  that 
Volume  19  now  issued  well  maintains  the  previous 
standard  of  excellence.  Albert  Hill  Fay,  the  editor, 
has  had  the  full  advantage  of  Mr.  Ingalls'  highly 
developed  organization  for  the  collecting  and  record- 
ing of  facts  and  figures,  and  many  of  the  regular  con- 
tributors of  special  reviews  have  remained  faithful. 
For  instance,  L.  S.  Austin  continues  his  record  of  pro- 
gress in  the  metallurgy  of  copper,  and  C.  H.  Fulton 
still  writes  on  progress  in  cyanidation.  H.  O.  Hofman 
again  reviews  the  metallurgy  of  lead,  W  R.  Ingalls 
the  metallurgy  of  zinc,  and  R.  H.  Richards  ore- 
dressing  and  gold  milling.  The  general  scope  of  the 
volume  is  much  more  confined  to  North  America  than 
formerly.  Mr.  Fay  has  only  had  one  year's  editorship  ; 
he  has  now  left  to  join  the  American  Mining  Bureau. 

The  Diamond.  By  W.  R.  Cattelle.  Cloth  octavo. 
440  pages,  illustrated.  London  :  John  Lane.  Price 
7s.  6d.  For  sale  by  The  Mining  Magazine. 
This  is  an  American  book  written  from  the  point  of 
view  of  a  commercial  dealer  having  an  inquiring  mind 
and  aptitude  for  intelligent  study.  The  information 
given  relating  to  the  marketing  of  diamonds  is  first- 
hand, and  is  therefore  of  interest  to  those  who  want  to 
know  how  it  is  possible  for  so  many  million  pounds' 
worth  of  diamonds  to  be  sold  every  year  and  the  price 
still  maintained.  But  it  does  not  help  the  buyer  or  the 
dillettante  to  judge  diamonds  for  himself ;  rather  is 
he  advised  to  find  a  dealer  of  repute  and  trust  him. 
The  rest  of  the  book  consists  of  a  collection  of  facts  and 
fancies  connected  with  the  stone.  There  is  a  chapter 
on  celebrated  diamonds  and  their  history,  which  in- 
cludes rumour  and  fable  as  well  as  fact,  but  without 
much  attempt  to  analytically  differentiate.  The  mines 
of  India,  Brazil,  South  Africa,  and  elsewhere  are 
described  in  great  detail.  A  chapter  is  devoted  to  the 
geology  and  the  theories  of  origin.  '  Diamonds  in 
Literature  '  gives  the  more  poetic  side  of  the  subject, 
but  seems  out  of  place  in  a  book  breathing  dollars  on 
every  page.  The  author  is  more  at  home  in  describ- 
ing the  sorting  and  judging  of  stones,  the  varying 
colouring  and  flaws,  and  the  methods  of  cutting  and 
polishing.  His  lack  of  first-hand  knowledge  on  other 
subjects  is  shown  by  errors  in  names,  such  as  "Philip- 
son  Snow  "  instead  of '  Stow, '  and  Barnett "  J ."  Barnato, 
the  latter  mistake  obscuring  the  old  family  name. 

Copper  Deposits  of  the  Appalachian  States. 
By  Walter  Harvey  Weed     Paper  covers,  166  pages, 
with  many  illustrations  and  maps.      Washington  : 
The  United  States  Geological  Survey. 
This  is  Bulletin  No.  455  of  the  United  States  Geo- 
logical Survey,  and  it  describes  the  copper  mines  of 
Vermont,  New  Jersey,   Massachusetts,  Virginia,  and 
North  Carolina,  that  in  earlier  days  were  important 
producers,  and  the  Ducktown  mines  of  Tennessee  and 
Kentucky  that  still  contribute  their  share  of  copper. 


OCTOBER,    1911 


315 


COMPANY   REPORTS 

Alaska  Treadwell. — This  company  was  formed  in 
San  Francisco  in  1890  to  acquire  the  Paris  mine  on 
Douglas  Island,  Alaska,  on  the  opposite  side  of  the 
Gastineau  channel  to  Juneau.  Adjoining  properties 
on  the  same  lode  have  been  developed  and  worked  by 
the  same  people  Of  these  the  700  ft.  Claim  mine  of 
the  Alaska  United  Co.  is  next  to  the  Treadwell  ;  and 
then  comes  the  Mexican  mine.  The  workings  of  these 
three  are  connected  on  several  levels.  Further  to  the 
east,  and  not  connected  with  the  Mexican,  is  the  Ready 
Bullion  mine  belonging  to  the  Alaska  United.  This 
statement  makes  clear  the  reason  for  the  new  policy  to 
be  adopted  of  hoisting  the  ore  from  the  deep  levels  of 
the  Treadwell,  700  ft.  Claim,  and  the  Mexican  from 
one  central  shaft.  For  this  purpose  the  main  shaft  of 
the  700  ft.  Claim  mine  is  to  be  enlarged  and  deepened. 
The  ore  so  raised  will  be  crushed  at  the  surface,  and 
then  distributed  by  electric  cars  to  the  various  stamp- 
mills.  The  winding  engine  will  be  capable  of  raising 
5000  tons  of  ore  from  a  depth  of  3500  ft.  in  20  hours. 


ton,  an  increase  of  over  700,000  tons  during  the  year. 
The  report  refers  to  the  100-ton  cyanide  plant  erected 
for  the  purpose  of  treating  the  sulphide  concentrate  on 
the  spot  instead  of  shipping  it  to  Tacoma.  Though  the 
process  evolved  was  proved  to  be  highly  advantageous, 
the  plant  is  not  in  operation,  as  the  contract  with  the 
Tacoma  smelter  has  not  expired.  The  electric  power- 
station  at  Sheep  creek  has  been  completed  and  is  in 
use.  The  water  used  for  generating  the  current  is 
diverted  from  the  channel  of  the  creek  a  mile  from  the 
power  house  on  Gastineau  channel  and  612  ft.  above 
it.  There  are  two  1000  kilowatt  generators  each  driven 
by  a  Pelton  wheel.  The  current  is  stepped  up  to  22,000 
volts  and  transmitted  9  miles  to  Treadwell,  where  it  is 
transformed  to  2300  volts,  at  which  pressure  it  is  dis- 
tributed. 

Pena  Copper. — This  copper  and  sulphur  mine  in 
the  South  of  Spain  has  been  worked  by  an  English 
company  since  1900,  having  been  previously  managed 
from  Belgium.  The  Siemens  group  own  large  interests 
in  the  company.  Nicol  Brown  is  chairman,  Harvey 
&  Wilbraham  are  the  consulting  engineers,  and  H. 


ALAS 


/    "  ----.  /CLAIM   ; 

(  ^~^  ■■,      Shafh       / 

/     TREADWELL        lfA/asJ<aUnifedji 


MEXICAN 


READY    BULLION 
^haFr 


i( Alaska  Unifed) 


THE   ALASKA   TREADWELL  GROUP    OF  MINES. 


and  it  will  be  driven  by  steam.  The  plan  given  here- 
with shows  the  position  of  the  various  properties,  and 
we  would  mention  here  that  the  deeper  workings  are 
vertically  below  the  Gastineau  channel,  particularly 
in  the  case  of  the  Ready  Bullion  mine.  The  annual  re- 
port now  issued  by  the  Alaska  Treadwell  covers  the 
year  ended  May  31.  It  is  announced  that  in  future,  in 
order  to  conform  with  Californian  laws,  the  fiscal  year 
will  be  made  to  coincide  with  the  calendar  year,  so 
early  in  1912  a  report  will  be  issued  covering  the  19 
months  from  June  1,  1910  to  December  31,  1911.  The 
present  report  shows  that  the  240-stamp  mill  ran  181 
days  under  steam  and  168  days  under  water-power, 
while  the  300-stamp  mill  used  electric  current  for 
17  days  and  water-power  for  209  days.  The  total 
amount  of  ore  milled  was  770,084  tons,  an  increase 
of  25,858  tons  over  the  previous  year.  The  yield 
was  $1,081,858  by  amalgamation,  or  $1'40  per  ton, 
and  1730,441  from  14,221  tons  of  pyritic  concen- 
trate sent  for  treatment  at  the  Tacoma  smelter,  or 
95  cents  per  ton.  The  total  yield  was  |1, 812, 299,  or 
$235  per  ton  milled.  A  year  ago  the  yield  was 
$2,079,318,  or  $279  per  ton  milled.  The  year  be- 
fore that  the  yield  was  $2'21  per  ton.  The  cost 
was  $1,195,949,  and  other  income  besides  the  sale  of 
gold  was  $93,962,  so  that  the  profit  was  $710,311, 
or  92  cents  per  ton.  Out  of  this  $600,000  was  dis- 
tributed as  dividend  and  $100,000  written  off  for 
depreciation  of  plant.  The  ore  reserve  on  May  15 
^vas  estimated  at  6,637,370  tons,  averaging  $3 '14  per 


Schreck  is  general  manager.  When  the  mine  was 
acquired  by  the  English  company,  the  finances  and 
methods  of  management  had  to  be  extensively  reor- 
ganized. The  issued  capital  is  ;^537,600  and  there  are 
;f32,300  debentures  outstanding,  /67,700  having  been 
redeemed  from  profits.  Dividends  of  5,  5,  4,  and  7.^% 
were  paid  from  1903  to  1906,  but  none  since.  During 

1909  special  expenditure  was  incurred  in  connection 
with  the  removal  of  overburden,  so  that  it  was  impos- 
sible to  distribute  any  dividend,  and  the  profits  for 

1910  have  been  conserved,  partly  because  of  the  long 
continued  dispute  originated  by  the  Rio  Tinto  Co. 
The  report  for  1910  now  published  shows  that  during 
the  year  132,559  tons  of  ore  was  raised  ;  of  this,  64,879 
tons  was  sent  to  the  leaching  floors,  and  67,680  tons 
delivered  for  export.  A  year  ago  it  was  decided  to 
sell  proportionately  more  ore  for  export  ami  to  treat 
less  on  the  spot  for  copper  content,  so  the  figures  for 
1910  differ  materially  from  those  of  1909,  when  of  the 
130,784  tons  raised  81,116  tons  was  sent  to  the  heaps 
and  49,668  tons  exported.  The  production  during  1910 
of  finecopperby  precipitation  was  1017  tons.  Theship- 
ments  were  :  cupreous  ore  19,260  tons,  sulphur  ore 
47,498  tons,  leached  ore  78,052  tons,  total  144,810tons, 
The  net  profit,  after  payment  of  debenture  interest  and 
taxes  was  /32,844.  Out  of  this,  ;^10,900  was  devoted  to 
the  redemption  of  debentures,  and  the  balance  carried 
forward.  The  position  as  regards  water  supply  is  ex- 
cellent, as  rain  has  been  plentiful.  The  difficulties  in 
connection  with  transport  by  the  Rio  Tinto  railway  will 


316 


THE    MINING    MAGAZINE 


within  a  short  time  be  obviated,  as  the  concession  for 
the  new  railway  has  been  granted,  and  construction  is 
to  be  commenced  forthwith.  The  company  has  been 
much  worried  lately  by  lawsuits  brought  by  the  Rio 
Tinto  company  in  connection  with  the  agreement  re- 
lating to  transport  of  ore,  etc.,  over  the  latter  com- 
pany's railway  to  the  port  of  Huelva.  According  to 
this  agreement  the  Pena  company,  in  return  for  trans- 
port facilities,  undertook  not  to  cut  the  prices  of  their 
produce  in  competition  with  the  Rio  Tinto  company. 
In  the  lawsuits  it  was  alleged  that  this  had  been  done 
by  the  Pena  company,  but  the  first  Court  and  the 
Court  of  Appeal  held  that  the  allegation  was  unsub- 
stantiated. More  recently,  a  similar  action  has  been 
brought  in  Spain,  a  proceeding  contrary  to  the  agree- 
ment, which  provided  that  all  disputes  should  be 
settled  in  the  English  courts  Under  these  circum- 
stances, it  is  not  surprising  that  the  directors  of  the 
Pena  company  express  their  gratification  at  the  fact 
that,  when  the  new  railway  is  completed,  they  will  be 
independent  of  the  Rio  Tinto  company. 

San  Miguel  Copper. — This  company  was  formed  in 
1904  to  acquire  from  Spanish  proprietors  the  San 
Miguel  copper  and  sulphur  mine  in  the  south  of 
Spain.  Owing  to  mismanagement,  the  directors  had 
to  resign  four  years  ago,  and  the  control  passed  into 
the  same  hands  of  the  Pena  above-mentioned.  The 
finances  were  drastically  reorganized  and  a  better 
system  of  mining  devised.  The  report  now  issued 
covers  the  year  1910.  It  shows  that  the  mining  of 
ore  by  opencut  has  been  restricted  owing  to  the  neces- 
sity for  removing  more  overburden,  and  that  not  until 
1912  will  the  output  be  restored  to  its  normal  level. 
The  amount  mined  was  71,791  tons,  as  compared  with 
78,849  tons  in  1909.  Of  this  output,  62,276  tons  was 
sent  to  the  leaching  floors  and  9515  tons  entered  for 
export.  The  production  of  copper  by  the  precipita- 
tion process  was  730  tons,  an  increase  of  88  tons  over 
1909.  The  deliveries  of  leached  ore  were  45,309  tons. 
After  allowing  /4354  for  depreciation,  the  net  profit 
was  /'5656,  out  of  which  the  balance  of  mine  develop- 
ment amount,  /1865,  was  written  off,  and  the  remain- 
der carried  forward.  The  development  work  done 
during  the  year  gave  good  results,  and  the  ore  reserve 
was  increased  by  38,000  tons,  to  620,000  tons.  Several 
promising  indications  have  made  it  possible  to  increase 
the  amount  of  development  work.  During  the  current 
year  the  shipments  of  cupreous  ore  and  leached  ore 
have  been  gradually  increasing. 

Globe  &  Phoenix. — The  interim  report,  covering 
the  six  months  ended  June  30,  of  the  leading  Rhodesian 
gold  mine  shows  that  the  amount  and  value  of  the  re- 
serve ore  are  well  maintained.  The  figures  at  June  30 
were  179,040  tons,  averaging  36  dwt.,  as  compared 
with  181,137  tons,  averaging  352  dwt.  on  December 
31  last,  in  the  meantime  36,619  tons  being  extracted. 
Of  this  ore,  28,184  tons  was  high-grade,  assaying  116 
dwt.  per  ton  over  51  inches,  figures  much  the  same  as 
on  December  31.  The  most  recent  developments  on 
the  17th  and  18th  levels  continue  to  disclose  rich  ore. 
One  of  the  drifts  30  ft.  long  assays  12oz.  over  32  inches, 
and  at  one  point  the  average  of  the  face  was  35  oz.  The 
ore  raised  during  the  half-year,  36,619  tons,  gave  49,611 
oz.  by  amalgamation  ;  the  feed  averaged  37 dwt.  and  the 
tailing  639  dwt.  In  the  sand-plant,  13,083  tons  yielded 
609  oz.,  the  feed  containing  485  dwt.  and  the  tailing 
377  dwt.,  and  in  the  slime-plant  15, 196  tons  of  current 
and  accumulated  slime  yielded  1746  oz.  In  addition, 
1718  tons  of  concentrate  was  roasted  and  cyanided 
yielding  5444  oz.  The  total  production  was  57,41 1  oz. 
It  will  be  seen  that  the  sand-plant  is  giving  poor  re- 
sults, and  H.  T.  Brett,  the  consulting  metallurgist,  has 


decided,  as  foreshadowed  in  his  article  in  this  maga- 
zine for  July,  to  erect  roasting  furnaces  with  sufficient 
capacity  to  treat  200  tons  of  accumulated  and  100  tons 
of  current  sand  per  day.  The  cost  of  the  new  instal- 
lation is  estimated  at  ^34,500.  The  revenue  from  the 
sale  of  gold  during  the  half-year  was  ;^242,259,  and 
the  profit  at  the  mine  /181,868.  The  working  cost, 
including  development  redemption,  was  33s.  3d.  per 
ton.  The  consulting  engineer,  H.  A.  Piper,  and  the 
manager,  Theodore  Haddon,  give  details  of  the  pro- 
gress of  development  and  of  various  improvements 
made  in  the  hoisting  and  pumping  plant.  They  report 
that  before  long  it  will  be  necessary  to  inaugurate  a 
system  of  ventilating. 

Mount  Bischo'f  Tin. — The  half-yearly  report  of 
the  premier  tin  mine  of  Tasmania,  covering  the  year 
ended  June  30,  shows  that  owing  to  scarcity  of  labour 
it  has  not  been  possible  to  do  any  prospecting  or  to 
complete  the  erection  of  the  new  plant  to  which  we 
referred  in  our  issue  of  April  last.  The  output  of  ore 
and  concentrate  therefore  did  not  show  the  increase 
that  was  expected.  The  amount  of  ore  mined  was 
113,441  tons  and,  after  sorting,  101,310  tons  was 
sent  to  the  mill.  During  the  previous  six  months  the 
figures  were  123,508  tons  and  110,664  tons.  Though 
the  amount  of  ore  treated  was  rather  less,  the 
grade  was  higher,  so  that  the  yield  was  550  tons 
of  concentrate,  exactly  the  same  as  before.  The 
smelting  works  at  Launceston  treated  this  amount 
and  also  1240  tons  of  custom  ore.  The  company's 
profit  during  the  half-year  was  /43,377,  of  which 
/^22,500  was  distributed  as  dividend,  /10,341  written 
off  for  depreciation,  /8528  paid  for  new  plant,  /1932 
spent  on  a  new  dam,  and  /1397  on  development  work, 
besides  providing  for  taxes,  etc.  For  the  previous 
half-year  the  profit  was  /35,311,  and  the  dividend 
/2 1,000.  The  directors  report  that  the  new  reservoir 
on  the  Waratah  river  has  been  completed,  and  it  is 
expected  that  in  future  the  mine  will  never  be  short  of 
water  even  in  the  driest  season. 

Anchor  Tin. — This  English  company  works  an  un- 
usually low  grade  tin  mine,  or  rather  open  stockwork, 
at  Lottah,  in  the  northeast  of  Tasmania,  and  since  its 
formation  in  1895  has  never  made  any  divisible  profit. 
On  two  occasions,  in  1902  and  1909,  it  has  been  neces- 
sary to  reconstruct  and  provide  further  funds.  The 
capital  now  consists  of  /25,159  in  ordinary  shares  and 
/6540  in  preference  shares  ;  there  are  also  /25,000  of 
4%  debentures,  and  a  loan  of  ;^5000  obtained  from  the 
Government  for  the  specific  purpose  of  building  an 
aerial  ropeway  to  a  new  property,  the  Australian  mine. 
Bedford  McNeill  is  consulting  engineer  and  James  B. 
Lewis  is  manager.  The  report  now  issued  covers  the 
year  ended  March  31,  and  shows  that  the  drought 
which  so  much  interfered  with  the  operations  during 
the  previous  year  continued  for  some  time  into  the 
year  now  under  review,  and  it  was  not  possible  to  re- 
sume crushing  until  May  1910.  A  stoppage  of  half  the 
battery  from  the  same  cause  occurred  about  Christmas. 
Then  in  March  this  year  unusually  heavy  rains  com- 
menced and  did  much  damage  by  flooding.  During 
the  time  the  water  supply  was  ample,  the  labour  was 
insufficient,  and  the  battery  could  not  be  kept  fully  em- 
ployed. The  protracted  drought  had  naturally  caused 
the  men  to  drift  away,  and  owing  to  the  general  scar- 
city of  labour  throughout  Australia,  it  was  impossible 
to  attract  them  back  again  when  the  mill  resumed. 
During  the  twelve  months,  the  a\erage  number  of 
stamps  at  work  was  68  out  of  100,  and  the  quantity  of 
ore  treated  was  102,944  tons.  The  recovery  was  155| 
tons  of  concentrate  or  338  lb.  per  ton,  equivalent  to 
2'38  lb.  metallic  tin  per  ton.     These  figures  were  much 


OCTOBER,    1911 


317 


the  same  as  during  the  previous  period  ended  March 
31,  1910.  The  cost  of  mining,  milling,  and  smelting 
was  /18,054,  or  3s.  5d.  per  ton,  and  the  London  and 
other  expenses  brought  the  total  cost  to  /19,644.  The 
concentrate  is  treated  by  the  Mount  Bischoff  company 
at  the  Launceston  smelting  works.  The  new  property, 
the  Australian  mine,  was  early  this  year  brought  into 
communication  with  the  Anchor  by  the  completion  of 
the  aerial  ropeway,  and  durmg  the  short  time  it  was 
worked  before  the  close  of  the  year,  March  31,  4 J  tons 
of  concentrate  was  produced  from  this  source.  This 
property  has  not  been  purchased  outright,  but  is 
being  worked  on  the  agreement  that  75%  of  the  profits 
shall  go  to  the  Anchor  company.  Mr.  Lewis  reports 
hopefully  of  it,  but  enough  work  has  not  yet  been  done 
to  make  it  possible  to  give  an  exact  estimate  of  the 
future 

Kinta  Tin. — This  company  was  formed  in  London 
in  1900  to  acquire  tin-gravel  properties  in  Perak,  Malay 
Peninsula.  Osborne  &  Chappel  are  the  managers. 
The  dividends  have  been  steady,  and  have  increased 
from  10%  in  1902-3  to  30%  for  1909-10.  The  report 
now  issued  covers  the  year  ended  June  30,  and  shows 
a  net  profit  of  ;^23,101,  out  of  which  ;^15,000  has  been 
distributed  as  dividend,  being  at  the  rate  of  25%,  and 
the  remainder  allocated  to  capital  expenditure  for  a 
contemplated  extension.  During  the  year  the  output 
of  tin  concentrate  was  322  tons,  which  sold  for  /33,774, 
or  /104  per  ton.  The  cost  at  the  mine  was  /6305,  and 
London  expenses,  taxes,  payment  to  tributors,  etc., 
/4348,  leaving  aprofitas  already  mentioned  of  /23,101. 
The  yield  of  concentrate  was  rather  less  than  during 
the  previous  year,  owing  to  the  exceptional  drought. 
As  regards  the  contemplated  extension  of  operations, 
the  company  has  recently  obtained  a  concession  from 
the  Government  providing  for  a  greatly  increased 
water-supply,  which  will  make  it  possible  to  develop 
additional  properties.  The  necessary  expenditure  on 
such  a  scheme  will  be  nearly  /50,000,  which  means 
practically  doublmg  the  capital .  The  directors  intend 
to  go  slowly  in  this  matter  and  not  to  create  new 
capital  until  the  profitableness  of  the  proposition  is 
well  proved. 

Nigerian  Tin  Corporation. — We  recorded  the  flota- 
tion of  this  company  in  December    1909,  and  men- 
tioned that  it  was  formed  with  no  special  property  m 
view  but  for  the  purpose  of  taking  up  anything  that 
offered.     The  directors  have  all  had   expeiience  in 
tin  mining  in  Cornwall  or  the  Malay  States,  Oliver 
Wethered  being   chairman.     The  report  now  issued 
covers  the  period  from  the  date  of  formation  of  the 
company  to  March  31  of  this  year.    It  states  that  H.  O. 
Crighton,  the  manager,  has  acquired  two  sets  of  pro- 
perties, near  Bauchi  and  Ninkada  respectively.    Four 
properties    in   the  former  group   have    been   worked 
primitively  by  means  of  calabash  and  have  yielded 
sufficient  tin  to  pay  expenses.  A  sluicingplantis  now  on 
its  way,  and  when  in  operation  the  output  should  be  30 
tons  per  month.    The  Ninkada  properties  have  not  yet 
been  systematically  prospected,  but  tin  is  reported  to 
be  found  in  many  streams  and  flats.   The  company  has 
made  a  profit  by  the  sale  of  shares  in  other  companies, 
so  in  February  ;^3978  was  distributed  as  dividend, 
being  at  the  rate  of  10% .     Since  then,  further  capital 
has  been  expended,  bringing  the  total  issue  so  far  to 
/45,782.      At  the  meeting  of  shareholders,  the  chair- 
man gave  some  further  information  about  the  cost  of 
power.     Up  to  the  present  time  wood  has  been  used 
as  fuel,  but  the  engineer  has  recommended  the  pro- 
vision of  power  from  a  waterfall,  not  far  from  the  pro- 
perty, from  which  200  to  300  hp.  can  easily  be  obtained 
by  pipe-line. 


El  Ore  Mining  &  Railway. — The  report  of  this 
company  operating  the  gold  mine  100  miles  northwest 
of  Mexico  City  for  the  year  ended  June  30  last  shows 
that  no  material  damage  was  done  during  the  revolu- 
tion, though  operations  were  hindered  by  difficulties 
in  connection  with  the  transport  of  supplies,  and  by 
the  unrest  caused  by  the  presence  of  armed  bodies  of 
men.  As  we  gave  a  historical  record  of  the  company 
in  our  issue  of  October  last  year,  we  need  not  now  re- 
capitulate. The  point  of  interest  at  present  in  connec- 
tion with  the  mining  and  metallurgy  is  that  increasing 
amounts  of  ore  are  being  treated,  of  substantially  less 
content,  and  at  a  much  lower  cost  per  ton,  and  that 
the  divisible  profit  has  been  maintained.  During  the 
past  year,  360,294  tons  of  ore  yielded  bullion  worth 
fi2,389,349,  or  $663  per  ton  ;  these  figures  compared 
with  316,138  tons,  $2,562,705,  and  $810  for  the  pre- 
vious twelve  months.  The  recovery  was  87%  as  com- 
pared with  91%.     On  the  other  hand  the  cost  was 


Sca/e  of  Miles 


The  El  Oro  District. 

$1,405,016  or  $390  per  ton,  as  against  $1,557,889  or 
$493  per  ton.     During  the  last  three  years  or  so  the 
ore  has  been  all-slimed  and  cyanided .   The  costs  of  min- 
ing and  treatment  are  still  being  lowered,  and  A.  F. 
Main,  the  manager,  has  made  further  improvements 
recently.     The  reserve  on  June  30  was  estimated  at 
484,139  tons,  averaging  $7  66  gold  and  3  oz.  silver  per 
ton    a  total  of  $9' 10  ;   this  compares  with  441,639  tons 
averaging  $950  a  year  ago.     This  ore  is  in  the  San 
Rafael,  San  Patricio,  and  Descubridora  veins.     In  ad- 
dition to  these,  work  is  being  done  on  the  No.  4  or 
Victoria  vein  in  the  Somera  property,  and  the  indica- 
tions point  to  the  vein  becoming  an  important  pro- 
ducer     As  regards  the  railway,  the  profits  have  been 
lower,   the  figure  being  $103,120   as    compared  with 
$1''4  254    This  fall  is  however  unimportant  and  speaks 
well  for  the  ability  of  the  management  in  tiding  over 
troublous  times.     In  the  company's  profit  and  loss 
account  /25,000  is  allowed  for  depreciation  ;  the  divi- 
dend absorbed  ;^172,125,  being  at  the  rate  of  15%.  and 
bringing  the  total  distribution  since  the  formation  of 
the  company  to  ;/^l,525,437. 


318 


THE    MINING    MAGAZINE 


Salisbury  Gold. — This  company  was  formed  under 
Natal  laws  in  1886  to  acquire  a  small  property  on  the 
outcrop  in  the  central  part  of  the  Rand,  and  is  under 
the  same  control  and  management  as  its  neighbour 
the  Jubilee,  which  has  recently  suspended  operations. 
The  two  mines  are  surrounded  by  the  Ferreira,  City 
&  Suburban,  and  Village  Main  Reef.  Milling  com- 
menced in  1887,  and  the  joint  mill  contains  100  stamps, 
of  which  60  belong  to  the  Salisbury.  During  the  year 
ended  June  30,  109,143  tons  was  mined  and,  after 
sorting,  93,396  tons  was  sent  to  the  mill,  where  12,519 
oz.  was  extracted  by  amalgamation  ;  59,775  tons  of 
sand  yielded  6125  oz  ,  and  27,632  tons  of  slime  yielded 
1107  oz.,  a  total  production  of  19,990  oz.  or  428  dwt. 
per  ton  milled,  as  compared  with  4'77  dwt.  a  year  ago. 
The  revenue  was  ;f84,817  and  the  cost  /69,511,  leav- 
ing a  profit  of  ;f  15,306,  out  of  which  ;f  13,500  has  been 
distributed  as  dividend.  The  manager,  W.  T.  Carr, 
estimates  the  ore  reserve  at  82,896  tons.  Most  of  the 
work  now  being  done  consists  of  cleaning  stopes,  and 
removing  as  many  pillars  as  possible.  As  already 
mentioned,  the  Jubilee  has  been  abandoned,  as  the 
workings  were  nearly  exhausted  and  had  become  un- 
safe ;  no  doubt  the  cost  of  working  at  the  Salisbury 
will  advance  in  consequence.  Two  years  ago  the 
company,  conjointly  with  the  Jubilee,  acquired  a  three- 
eighths  interest  in  the  Claremont  and  Nelly  Extra 
mines,  between  Bulawayo  and  Selukwe.  These  pro- 
perties were  floated  as  a  separate  company,  and  35,000 
new  shares  were  issued  by  the  Salisbury  company  for 
the  purpose  of  taking  up  their  quota.  Five  stamps 
are  at  work,  and  Nissen  stamps  are  being  erected. 

North  Anantapur. — This  company  was  formed  in 
June  1908  by  John  Taylor  &  Sons,  to  acquire  part  of 
the  property  in  Madras  Presidency,  India,  that  had 
been  developed  by  the  Anantapur  Gold  Field  Co.  The 
report  now  issued  covers  the  year  ended  June  30. 
During  this  period  the  monthly  output  has  been  gradu- 
ally raised  from  700  tons  to  1400  tons,  and  the  number 
of  stamps  running  has  increased  from  10  to  15.  The 
total  tonnage  treated  was  11,382,  and  the  gold  ex- 
tracted by  amalgamation  was  worth  ;^18,629,  or  32s.  8d. 
per  ton.  The  expenditure  was  ^20,545.  The  direc- 
tors are  proposing  to  issue  25,000  new  shares,  en- 
titling holders  to  a  20%  non-cumulative  dividend,  in 
order  to  provide  funds  for  prosecuting  the  develop- 
ment work  on  a  larger  scale.  W.  Stonor,  the  super- 
intendent, reports  that  at  the  northern  end  the  recent 
exploratory  work  has  revealed  several  profitable  shoots  ; 
at  one  place,  a  cross-cut  on  the  200  ft.  level  passed 
through  5  ft  of  ore  averaging  1  oz.  per  ton.  During 
the  year,  the  ore  reserve  has  increased  from  8500  tons 
to  14,000  tons.  Before  deciding  on  an  increase  of 
capital,  the  directors  sought  the  opinion  of  C.  H. 
Richards,  superintendent  of  the  Nundydroog  Co.,  and 
he  fully  confirmed  Mr.  Stonor's  views.  The  mine  is 
fully  equipped  with  winding  and  pumping  engines, 
and  has  a  14-drill  compressor  and  20  stamps,  so  that 
no  further  expenditure  is  required  in  this  direction. 
The  recovery  by  amalgamation  is  82% ,  and  the  amount 
of  gold  left  in  the  tailing  is  just  under  2  dwt.  At  some 
future  time  a  cyanide  plant  is  to  be  provided. 

Barramia  Mining  &  Exploration. — This  company 
operates  a  gold  mine  in  Upper  Egypt,  situated  63  miles 
eastward  from  Edfu  on  the  Nile.  It  was  formed  by 
John  Taylor  &  Sons  in  July  1909,  as  a  subsidiary  of 
the  Egypt  &  Sudan  Mining  Syndicate.  The  capital  is 
;^55,000,  divided  into  216,000  preference  shares  of 
2s.  6d.  each  entitled  to  a  10%  non-cumulative  dividend, 
and  112,000ordinary  shares  of  5s.  each.  The  purchase 
consideration  paid  to  the  syndicate  was  the  whole  of 
the  ordinary  shares,  ;^1350  in  preference  shares,  and 


/5000  in  cash.  The  remaining  205,200  preference 
shares  were  subscribed  in  cash  by  shareholders  in  the 
vendor  and  allied  syndicates.  The  preference  shares 
are  entitled,  in  addition  to  the  10%  dividend,  tof|ths 
of  the  subsequent  profits  in  any  one  year.  The  mine 
was  worked  by  the  ancients,  and  is  characterized  by 
veins  that  are  narrow  and  occasionally  of  high  value. 
The  present  report  covers  the  year  ended  June  30. 
During  that  period,  1861  tons  of  ore  was  mined  and 
milled,  and  gold  worth  /18,6S9  was  extracted.  The 
net  profit,  after  allowing  for  taxes,  London  expenses, 
and  depreciation,  was  £3360.  out  of  which  ;^2700  has 
been  paid  as  the  10%  preference  dividend.  In  addition 
^3857  has  been  spent  out  of  capital  on  buildings,  plant, 
and  shaft-sinking.  Transport  over  the  desert  to  Edfu  is 
one  of  the  troublesome  problems  During  the  year  a 
motor  wagon  of  2-ton  capacity  was  bought  ;  unfortu- 
nately it  proved  to  be  far  too  heavy  for  ploughing 
through  the  sands  of  the  desert,  so  it  has  been  dis- 
carded. In  January  last,  the  mill  was  doubled  by  the 
addition  of  5  stamps.  The  mill  now  contains  10  stamps, 
weighing  500  lb.  each,  and  can  crush  128  tons  per  day 
of  16  hours  through  30  mesh.  The  superintendent, 
Arthur  J.  Rickard,  gives  full  details  of  development 
work.  The  pockety  nature  of  the  ground  is  evidenced 
by  the  fact  that  in  a  winze  below  the  130  ft  level,  1  cwt. 
of  ore  contained  230  oz.  of  gold.  The  most  promising 
part  of  the  mine  is  Taylor's  reef,  which  has  recently 
been  proved  on  the  250ft.  level. 

Chillagot-. — This  company  was  formed  in  Melbourne 
in  1898  for  the  purpose  of  working  copper  and  lead 
deposits  in  North  Queensland  and  to  construct  rail- 
ways, and  it  has  now  a  great  ramification  of  interests, 
including  a  smelting  works,  mines,  railways,  holdings 
in  subsidiary  mining  companies,  and  contracts  for  the 
supply  of  custom  ore.  The  company's  own  mines, 
the  Zillmanton,  Boomerang,  and  Redcap,  are  not  as 
productive  as  formerly,  nor  are  the  ores  from  the 
Mungana,  a  subsidiary,  so  profitable  nowadays.  Dur- 
ing the  last  year  or  two,  supplies  of  copper  ore  have 
come  from  the  Einasleigh  mine,  particulars  of  which 
were  given  in  our  issue  of  April  last.  Mines  have  also 
been  acquired  at  Forsayth,  in  the  Etheridge  district, 
and  floated  as  a  separate  company.  The  company 
built  and  owns  the  Chillagoe  railway,  that  starts  at 
Mareeba,  and  is  now  nearly  completing  the  Emeridge 
railway  to  connect  Almaden  on  the  Chillagoe  railway 
with  Einasleigh,  Charleston,  and  Georgetown.  The 
capital  of  the  company  is  /452,856  in  shares,  and  there 
are  ;f800,000  debentures.  The  report  now  issued 
covers  the  year  ended  March  31  last.  The  Zillman- 
ton, Boomerang,  and  Redcap  mines  produced  only 
4670  tons  between  them.  The  first  named  yielded 
2253  tons  of  4j%  copper  ore,  and  from  the  others  the 
production  was  chiefly  fluxing  ore.  Development  work 
was  confined  to  the  Zillmanton,  and  the  prospects  are 
only  moderate.  The  mines  at  Forsayth  are  promising  ; 
they  contain  copper  and  lead  ores  with  high  gold  con- 
tents. At  the  smelting  works  a  copper  furnace,  a  lead 
furnace,  and  a  smaller  one  for  copper-lead  ores  have 
been  in  commission  during  the  year,  the  copper  fur- 
nace continuously,  and  the  lead  furnace  for  six  months. 
The  total  ore  treated  was  60,943  tons,  and  the  ship- 
ments were  2441  tons  of  lead  bullion  containmg  1053 
oz.  gold  and  197,371  oz.  silver,  and  3321  tons  of  blis- 
ter copper  containing  10,592  oz.  gold  and  315,254  oz. 
silver.  The  working  account  shows  a  profit  on  the 
mine  and  smelter  of  /21,000,  and  in  addition  there 
was  a  profit  on  the  railway  of  /'78,800,  so  that  the 
working  profit  was  /99,800.  Out  of  this  /28,665  went 
as  debenture  interest,  ;^10,400  as  general  expenses, 
and  /55,373  was  written  off  for  mine  development  and 


OCTOBER,    1911 


319 


for  depreciation.  The  shareholders  have  never  re- 
ceived any  dividend,  and  the  company  has  been  re- 
constructed twice,  in  1902  and  1905.  E.  A.  Weinberg 
is  consulting  engineer,  E.  J .  J .  Rodda  is  mine  manager, 
and  J.  Horsburgh  is  metallurgist. 

Mungana  Chillagoe. — This  company  was  formed  in 
Melbourne  in  1901  to  acquire  the  Girofla  and  Lady 
Jane  mines  from  the  Chillagoe  company,  which  still 
owns  apreponderating  interest  in  the  share  capital.  The 
ore  is  complex  and  of  varying  grade  and  constitution. 
It  occurs  in  bunches  in  limestone.  Most  of  it  consists  of 
mixed  argentiferous  lead-copper  sulphides,  but  there 
are  oxides  and  carbonates  present  as  well.   Separation 


of  the  year's  output  came  from  the  Girofla.  The  Lady 
Jane  is  still  burning,  or  at  least  is  still  hot,  and  great 
difficulty  is  experienced  in  reclaiming  the  lower  levels. 
As  regards  the  ore  reserves,  S.  N.  Rodda,  the  general 
manager,  estimates  them  at  55,000  tons  in  the  Lady 
Jane,  and  101,000  tons  in  the  Girofla. 

North  Broken  Hill. — We  recorded  in  our  May  issue 
that  this  company,  which  is  one  of  the  two  most  pros- 
perous silver-lead-zinc  mines  on  the  Barrier  range, 
New  South  Wales,  had  not  been  able  to  work  the  new 
lead-concentration  plant  to  full  capacity  owing  to 
shortage  of  labour.  The  half-yearly  report  now  issued, 
covering  the  period  ended  June  30,  shows  that  this 


PART    OF    NORTHS  EN     QUEENSLAND. 


by  water  concentration  is  impossible.  Originally  the 
whole  of  the  ore,  which  is  smelted  by  the  Chillagoe 
company,  was  first  treated  for  lead,  and  the  copper- 
lead  matte  then  sent  to  the  copper  furnaces.  During 
the  last  two  years,  however,  the  low  price  of  lead  has 
made  the  first  treatment  unprofitable,  so  the  ore  is  now 
sent  direct  to  the  copper  furnaces.  Much  of  the  lead 
content  is  therefore  sacrificed.  The  report  for  the  year 
ended  March  31  just  issued  shows  that  22,489  tons  was 
delivered  to  the  smelter,  averaging  by  assay  1736% 
lead,  744%  copper, and  1543  oz.  silver.  Themetalpaid 
for  was  1873  tons  lead,  1529  tons  copper,  and  350,073 
oz.  silver.  It  will  be  seen  that  the  returns  on  the  cop- 
per and  silver  were  about  the  normal  results  of  smelt- 
ing, but  that  over  half  the  lead  was  lost.  The  receipts 
were  /61,051  and  the  net  profit  ;^14,711,  which  was 
carried  forward.  Owing  to  the  fire  and  creep  at  the 
Lady  Jane  two  years  ago,  it  was  not  possible  to  raise 
more  than  8000  tons  during  the  year,  and  the  remainder 


difficulty  is  still  present,  and  indeed  has  caused  the 
output  of  the  mine  to  decrease  by  5000  tons  and  the 
profit  by  ;^8500.  The  ore  raised  was  127,407  tons,  and 
the  concentrator  treated  128,272  tons  averaging  159% 
lead,  13%  zinc,  and  6'4  oz.  silver.  The  production  of 
lead  concentrate  was  21,895  tons  assaying  714%  lead. 
61%  zinc,  and  205  oz.  silver,  being  a  recovery  of 
768%  of  the  lead  and  54-8%  of  the  silver.  The  zinc 
tailing  produced  was  67,413  tons,  assaying  36%  lead, 
167%  zinc,  and  32  oz.  silver.  This  was  delivered  to 
the  Amalgamated  Zinc  (De  Bavay's)  for  treatment. 
In  addition,  12,226  tons  of  slime  was  produced,  aver- 
aging 131%  lead,  16'1%  zinc,  and  82  oz.  silver.  The 
slime-treatment  plant  is  being  extended,  but  is  not  in 
use  yet.  The  old  slime  dump  containing  90,000  tons 
has  been  sold  for  7s.  6d.  per  ton  to  the  Junction  North 
company.  Owing  to  the  increase  in  wages  in  Australia, 
the  cost  of  operation  has  advanced  by  Is.  4d.  per  ton 
of  ore,  and  now  stands  at  14s.  7d.  per  ton.  The  profit 


320 


THE    MINING    MAGAZINE 


for  the  half-year  was  /66,808  ;  the  allowance  for  de- 
preciation was  ;^12,661,  and  ;^52,500  was  distributed 
as  dividend,  being  at  the  rate  of  30%  for  the  half  year. 
As  regards  developments,  the  reports  are  most  favour- 
able. The  reserve  above  the  1100  ft.  level  remains  at 
1,300,000  tons,  and  the  discoveries  on  the  1250  ft  level 
are  important,  the  cross-cut  passing  through  19  ft.  of 
ore  averaging  16^%  lead,  15^%  zinc,  and  1\  oz.  silver. 
Similarly  the  southern  body  on  the  1100  ft.  level  is 
being  proved  to  contain  valuable  additions  to  the  ore 
reserve,  four  cross-cuts  showing  the  uidth  of  the  lode 
to  be  50  to  70  ft.  wide,  and  assaying  as  high  as  the 
average  grade  of  the  mine. 

Broken  Hill  South  Silver.— This  and  the  North 
company,  particulars  of  which  are  given  in  the  pre- 
ceding paragraph,  are  the  two  most  prosperous  on  the 
Barrier  Range  at  the  present  time.  A  new  lead  con- 
centrator was  completed  at  the  beginning  of  1909,  but 
was  not  put  in  commission  immediately,  owing  to  delay 
in  fixing  a  satisfactory  contract  for  the  sale  of  concen- 
trate. Another  period  of  inactivity  occurred  at  the 
beginning  of  1910  owing  to  the  coal  strike.  Since  then 
the  operations  have  been  practically  continuous,  ex- 
cept for  a  short  time  at  the  beginning  of  1911  when 
the  full  complement  of  skilled  labour  could  not  be 
maintained.  The  report  for  the  half-year  ended  June 
30  shows  that  175,044  tons  was  mined  and  concen- 
trated, averaging  146%  lead,  13  6%  zinc,  and  65  oz. 
silver.  From  this  26,617  tons  of  lead  concentrate  was 
produced,  averaging  71  6%  lead,  52%  zinc,  and  23  2 
oz.  silver.  In  addition,  95,990  tons  of  zinc  tailing  was 
produced  averaging  3' 7%  lead,  176%  zinc,  and  38  oz. 
silver,  together  with  quartz  tailing  and  slime.  The 
zinc  tailing  was  delivered  to  the  Amalgamated  Zinc 
(De  Bavay's)  together  with  16,721  tons  of  accumulated 
tailing,  while 8991  tons  of  old  mill  tailing  averaging  1 1  % 
lead,  20%  zinc,  and  4oz.  silver  was  delivered  to  the 
Zinc  Corporation.  The  untreated  accumulations  con- 
sist of  over  a  million  tons  of  zinc  tailing  belonging  to 
the  Zinc  Corporation,  and  115,000  tons  due  to  the 
Amalgamated  Zinc  ;  also  261,692  tons  of  slime.  The 
income  from  the  sale  of  lead  concentrate  was  /209, 1 13, 
and  of  zinc  tailing  ;^41,945,  a  total  of  ;f  251, 058.  The 
profit  was  £72,51d>,  out  of  which  /60,000  has  been  dis- 
tributed as  dividend,  being  the  same  as  during  the  pre- 
vious half-year,  and  comparing  with  /20,000  this  time 
last  year.  As  regards  developments,  the  work  on  the 
1070  ft.  and  1170ft.  levels  has  made  substantial  addi- 
tions to  the  ore  reserve.  The  increase  in  the  rate  of 
wages  of  10%  since  January  1  has  added  Is.  Id.  to  the 
cost  per  ton,  but  economies  reduced  the  increase  to 
lid.  The  cost,  including  mining,  filling  stopes,  de- 
velopment and  concentrating  was  17s.  id.  per  ton 

New  Einasleigh.  —  This  company  was  formed  in 
London  in  1907  to  acquire  a  copper  mine,  situated  at 
the  junction  of  the  Einasleigh  and  Copperfield  rivers 
in  North  Queensland,  and  about  120  miles  on  the 
Etheridge  railway  south  of  Chillagoe.  The  control 
is  with  the  same  group  as  the  British  Broken  Hill  ; 
Alexander  Stewart  and  W.  H.  Woodhead  are  on  the 
board.  In  our  issues  of  July  last  year  and  April  of 
this  year  we  gave  particulars  of  the  ore  deposit.  The 
report  for  the  year  ended  January  31  has  just  been 
issued.  It  shows  that  20,096  tons  of  ore,  estimated 
to  contain  1374  tons  of  copper,  was  shipped  to  the 
Chillagoe  smelter,  and  realized  ;f22,583.  The  costs 
at  the  mine  were  ^'15,233,  and  other  expenses  /2956  ; 
after  paying  ;^2876  as  debenture  interest,  the  balance 
of  profit  was  ;^710.  Owing  to  delays  in  the  erection 
of  the  concentration  plant,  it  has  not  been  possible  to 
treat  the  large  amount  of  lower  grade  ore  that  has 
already  been  raised  to  surface.     The  plant  is  now  on 


the  spot,  but  as  the  company  is  short  of  funds,  it  has 
not  yet  been  put  into  commission.  Development  work 
in  the  mine  has  given  good  results  on  the  3rd  and  4th 
levels.  On  the  3rd  level  the  rich  shoot  has  been 
proved  for  266  ft.,  and  on  the  4th  level  for  245  ft. 
The  nature  of  the  ore  has  altered  with  depth  ;  in  the 
upper  levels  it  was  highly  silicious,  but  more  recently 
it  has  become  basic.  The  directors  are  therefore  con- 
sidering the  advisability  of  smelting  on  the  spot.  A 
scheme  for  raising  further  working  capital  for  the  pur- 
pose of  continuing  development,  erecting  the  concen- 
trator, and  building  a  smelter,  is  to  be  placed  before 
shareholders  H.  Adler  has  relinquished  the  manage- 
ment of  the  mine,  and  the  position  is  held  temporarily 
by  H.  P.  Wallmann. 

Ida  H. — This  gold  mine  is  situated  in  the  Mount 
Alargaret  district  of  West  Australia,  and  was  intro- 
duced in  London  in  1900  by  the  North-Waddington 
group.  From  1902  to  1906  satisfactory  dividends 
were  paid  on  the  small  capital  ;f54,000,  amounting 
to  142^%  in  all.  For  the  last  four  years  no  divisible 
profit  has  been  made.  The  report  now  issued  covers 
the  18  months  ended  June  30,  and  shows  that  20,940 
tons  of  ore  was  crushed  yielding  gold  worth  /55,341. 
The  mining  and  administration  expenses  were  ;f36,021, 
£,\11\  was  allowed  for  depreciation,  and  ;^16,083 
written  off  the  development  account.  At  the  end  of 
March  this  year,  Campbell  Shaw,  the  manager,  re- 
signed, and  Hooper,  Speak,  &  Feilding  were  ap- 
pointed consulting  engineers.  At  the  recommenda- 
tion of  their  local  partner,  R.  A.  Varden,  the  hoist- 
ing of  ore  was  suspended  in  June,  and  several  im- 
provements effected  above  and  below  ground,  the 
straightening,  re-timbering,  and  re-equipment  of  the 
shaft  being  the  most  important.  Milling  commenced 
again  in  September. 

TRADE    NOTES 

Most  of  the  trade  publications  mentioned  in  this 
column  are  available  for  distribution  and  the 
manager  of  ''The  Mining  Magazine"  will  be 
pleased  to  secure  copies  for  persons  interested. 

Users  of  Hand  Pumps  will  find  useful  information 
in  the  booklet  issued  by  W.  H.  Wilcox  &  Co. 

The  British  Humboldt  Engineering  Co.  report  the 
sale  of  a  second  Wetherill  separator  to  Davis  &  Soper, 
for  Tasmania. 

Dorr  Thickeners  have  been  adopted  at  the  new 
plant  erected  at  the  Globe  &  Phoenix  mine,  Rhodesia, 
for  the  cyanidation  of  roasted  antimonial  slime. 

Robert  Boby  Ltd.  make  the  '  Neckar  '  water  soften- 
ing and  boiler-mud  extracting  apparatus  and  have 
just  issued  a  16-page  booklet  illustrating  and  describ- 
ing its  application  and  advantages. 

The  British  Aluminium  Co.  have  issued  under  date 
of  September  1911,  a  20-page  bulletin  describing  the 
uses  of  aluminium  in  the  electrical  industry,  giving 
particular  attention  to  its  value  in  the  transmission  of 
electric  current. 

Walker  Brothers  have  issued  a  pamphlet  devoted 
to  Air  Compressing  Machinery.  It  deals  in  detail 
with  the  increased  efficiency  secured  from  higher  pis- 
ton speed  made  possible  by  the  use  of  a  new  type  of 
air  valve.  The  latest  compressors  are  also  equipped 
with  an  improved  unloading  device. 

The  McKiernan-Terry  Drill  Co.  have  issued  a  new 
and  comprehensive  catalogue  describing  their  core- 
drill.  It  contains  information  compiled  from  opera- 
tions in  the  field,  and  is  particularly  interesting  in  de- 
scribing successful  bores  made  up  to  30  in.  diameter, 
and  illustrates  cores  taken  from  these  large  holes. 


I 


The  Mining  Magazine 


Vol.  V. 


LONDON,   NOVEMBER    191 


No.  5 


Scientia  non  habet  initnicutn  nisi  ignorantem. 


T.    A.    RICKARD,    Editor.  EDGAR    RICKARD,    Business  Manager. 

PUBLISHED  BY  THE  MINING  PUBLICATIONS  LTD.,  at  819  SALISBURY  HOUSE,  LONDON,  E.C 

Issued    on    the    15th   day   of   each    month. 

Telegraphic  Address  :    Oligoclase.     Codes:  MciVej/i,  both  editions.     Telephone:    8938   London    Wall. 

Branch  Offices  • 
SAN  FRANCISCO:  420  MARKET  STREET.     CHICAGO:  734  MONADNOCK  BUILDING.      NEW  YORK:  29  BROADWAY 

Agents  for  the  Colonies  : 
GORDON    &    GOTCH,    LONDON,    MELBOURNE,    Etc.    (SOUTH    AFRICA  :    CENTRAL    NEWS    AGENCY,    LTD.) 

Registered  with  the  G.P.O.  for  transmission  to  Canada  by  Canadian  Magazine  Post. 

SUBSCRIPTION    RATES. 

United  Kingdom  and  Canada,  12  Shillings  (Single  Copy,  Is.)    ...    Abroad,  16  Shillings  (Single  Copy,  Is.  4d.) 


CONTENTS. 


Review  of  Mining. 


PAGE 

322 


Editorial 

Notes 328 

West  Africa  329 

Camp  Bird — Santa  Gertrudis  330 

Prospects  in  Rhodesia 332 

Waihi 333 

The  Sale  of  Tin 334 

The  Gold  Fields  Report 336 

Cyanidation  in  Colorado 337 

The  Imperial  College  Union 338 

Impoverishment  in  Depth 340 

Meticulous  Estimates 341 

Official  Opinions 342 

Origin  of  Petroleum 343 

Special  Correspondence 

Johannesburg 345 

San  Francisco 348 

Toronto 349 

Camborne 351 

Melbourne 352 

New  York 355 

Articles 

Milling  Methods  at  Stratton's  Inde- 
pendence  Philip  Argall  361 

Progress  at  Porcupine..//.  //.  Johnson  371 

Recent  Progress  on  the  Klondyke 

F.  L.  Morris  374 

Mining  Methods  at  Braden,  Chile, 
Frank  Langford  376 

Early  Days  on  the  Rand 

D.  B.  Schuitema  379 


PAGE 

Statistics  of  Production 358 

Metal  Markets 359 

Personal 360 

Discussion 

A  Miner's  Protest  Reef  Miner  381 

Percentage  of  Recovery 

//.  C.  Parmelee  3S1 

Buying  Prospects...  VV^.  A/^.  Cmw wings  383 

Pyrites  Deposits  of  Huelva 

A.  M.  Finlayson  383 

Statements  of  Cost G.A.  Denny   384 

Malaria Noiil  G.  Hackney  384 

Precis  of  Technology 

Boring  for  Coal  in  Buckinghamshire..  3S5 

Wire  Ropes  for  Mining  Purposes 3S5 

Metallurgy  at  Globe  &  Phoenix 386 

Treating  Copper- Lead  Matte 386 

Forbes'  Slime  Thickener 386 

Geology  of  Cobalt  386 

Smelter  Gases 388 

The  Economics  of  Tube-Milling  388 

Lapland  Iron  Ores 388 

Electric  Smelting  of  Zinc  Ores 388 

Imbert-Fitzgerald  Zinc  Process 389 

Zinc  Extraction  by  Bisulphite  Process  390 

The  Standard  Tin  Contract 390 

Refining  Gold  and  Silver  Bullion 390 

The  Ashio  Copper  Mine,  Japan 390 

Current  Literature 391 

Books  Reviewed 392 

Company  Reports 394 

Trade  Notes  398 


REVIEW    OF    MINING 


Introductory. — The  mining  market  has  maintained  for  the  remaining  three  months 

exhibited  a  better  tone  since  our  last  issue  the  total  for  the  year  will  be  8,200,000  ounces, 

appeared.      On   November  4   the   Moroccan  or  about  ;^35, 000, 000,  as  against  7,532,322  oz. 

treaty  was  signed  by   France  and  Germany,  and  ;^3 1,995, 266  in  1910.     On  analysing  the 


ratifying  a  peaceful  settlement  of  that  diffi- 
culty. The  result  had  been  discounted,  but  it 
was  no  less  gratifying  when  it  became  a  fact. 
The  Chinese  revolution,  on  the  other  hand, 
has  not  affected  the  European  share  markets 
as  yet,  owing  to  the  aloofness  of  the  Western 
world,  but  the  monetary  requirements  cf  the 
combatants  on  the  Yangtze  Kiang  have  in- 
fluenced the  demand  for  silver,  and  are  likely 
to  do  so  mcreasingly.  A  recovery  at  New 
York  has  contributed  to  a  more  hopeful  out- 
look. The  Gold  Fields  report  and  the  later 
speech  of  the  chairman.  Lord  Harris,  have 
had  a  cheering  effect.  The  market  at  Johan- 
nesburg has  broadened  considerably.  A  large 
bear  account  has  been  disclosed  in  Tangan- 
yikas,  where  matters  appear  to  be  coming  to 
a  head.  The  Rhodesian  department  is  more 
lively  and  several  new  issues  are  imminent. 
The  money  market  is  favourable  to  new 
flotations,  several  large  non- mining  issues 
having  been  largely  over-subscribed  recently. 
If  we  are  spared  further  untoward  happenings 
on  the  Rand  we  may  expect  a  steady  recovery, 
for  the  supply  of  labour  improves  at  this 
season  in  South  Africa,  and  the  beginning  of 
winter  brings  financiers  from  the  covert  and 
the  links  to  Throgmorton  Street. 

Transvaal. — The  statistics  of  gold  output 
for  September  created  a  good  impression,  al- 
though they  merely  indicated  a  continuance 
of  the  rate  of  production  recorded  in  the  two 
preceding  months.  The  yield  was  700,625 
ounces,  worth  £2,916,065,  for  the  short  month 
of  30  days,  as  compared  with  713,407  ounces, 
worth  ;^3,030,360,  during  the  31  days  of 
August.     If   the    present    rate    of   output   is 


returns  it  is  seen  that  the  average  yield  was 
8  pence  per  ton  better  in  September  than  in 
August,  which  suffered  from  the  East  Rand 
collapse,  and  2d.  per  ton  better  than  in  July. 
The  average  cost  for  the  month  was  4d.  higher 
than  in  August,  so  that  the  resulting  profit  was 
4d.  per  ton  higher.  The  total  profit  was 
^952,665,  which  is  the  lowest  since  March. 
As  regards  labour,  the  decrease  in  the  supply 
of  natives  was  only  191,  as  against  a  pre- 
liminary estimated  loss  of  500  ;  but  last  year 
in  September  there  was  a  gain  of  1369  ;  there- 
fore the  figures  are  disappointing.  In  October 
the  loss  was  548. 

Anxiety  concerning  the  water-supply  on 
the  Rand  was  accentuated  by  the  action  taken 
by  the  local  Water  Board,  which  reduced  the 
supply  to  the  mines  by  30%  ;  but  the  breaking 
of  the  drought  announced  on  October  25  had 
a  reassuring  effect.  Most  of  the  mining  com- 
panies have  reservoirs  of  their  own  and  their 
use  of  the  municipal  supply  is  due  to  its  rela- 
tive cheapness  and  purity.  No  cause  for 
alarm  exists.  Recent  reference  to  excessive 
mortality  among  natives  working  underground 
in  the  mines  of  the  Rand  would  suggest  that 
silicosis  was  at  its  worst  in  the  gold  mines, 
but  it  appears  that  in  1910  the  mortality  in 
the  diamond  mines  of  South  Africa  was  44'9 
per  thousand,  as  compared  with  32'6  in  the 
deep-level  gold  mines  and  24*7  in  the  outcrop 
mines.  The  exceptionally  heavy  rate  of  mor- 
tality at  the  Premier  diamond  mine  is  engaging 
the  attention  of  the  Health  Department. 

The  New  Modderfontein  report  is  cheerful, 
showing  increased  gold  output,  larger  profit, 
and  bigger  dividends  ;  in  other  words,  it  is  an 


322 


NOVEMBER,    1911 


323 


expanding  enterprise.  The  reserve  is  now  es- 
timated at  3,342,000  tons  at  7i  dwt.  per  ton, 
as  against  the  average  yield  for  the  past  year, 
namely,  29s.  5d.  per  ton.  The  working  cost 
is  17s.  4d.  per  ton,  but  this  relatively  high 
figure  is  attributed  to  outlay  in  preparatory 
work. 

The  Benoni  mill  was  started  at  the  end  of 
September  and  would  have  started  earlier  if 
a  sufficient  supply  of  native  labour  had  been 
available.  In  this  mill  the  Arbuckle  dewater- 
ing  cones  have  been  adopted,  followed  by  the 
Way-Arbuckle  agitators.  On  September  29 
the  new  mill  at  the  Modderfontein  B  mine 
commenced  crushing,  and  in  the  same  week 
the  Crown  Reef  mill  of  the  Crown  Mines  was 
started.  This  makes  three  plants  that  entered 
the  productive  stage  at  about  the  same  time  ; 
the  haste  to  get  under  way  being  due  to  an 
Act  passed  by  the  Union  Parliament  whereby 
no  mills  that  were  started  after  September  30 
are  allowed  to  operate  on  Sundays.  The  law 
does  not  affect  those  already  in  operation  at 
that  date. 

The  October  outputs  and  profits  of  the 
General  Mining  (or  Albu)  group  are  excel- 
lent, especially  at  the  Meyer  &  Charlton, 
which  gave  a  profit  of  ;^1 3,045,  the  highest 
recorded  in  the  history  of  that  mine.  The 
average  working  cost  for  the  group  was 
17s.    lid.  per  ton.  > 

The  Zaaiplaats,a  tin  mine,  has  been  earning 
big  profits,  paying  ;^1 10,000  or  185%  in  divi- 
dends, leaving  a  balance  of  £27,615,  besides 
£l2,\92  spent  in  plant  during  the  year  ending 
July  31.  Additional  stamps  are  to  be  erected, 
increasing  the  mill  to  35  stamps. 

Rhodesia. — The  September  gold  output 
was  53,615  ounces,  worth  £22b,lll ,  this  being 
a  decrease  of  4275  oz.  or  £\1 ,9Z5  as  against 
the  month  preceding.  The  number  of  pro- 
ductive mines  decreased  from  174  to  168. 
However,  these  figures  were  deemed  satis- 
factory, having  regard  to  the  shortage  of 
labour,  which   it   was  feared  would  cause  a 


more  serious  diminution  of  the  output.  The 
premier  mine,  the  Globe  &  Phoenix,  is  respon- 
sible for  most  of  the  loss,  the  individual  de- 
crease being  2811  oz.,  that  is,  from  11,017  to 
8206  ounces. 

Reports  from  the  Shamva  continue  excel- 
lent, 310,000  tons  having  been  added  to  the 
reserve,  which  is  now  1,555,000  tons  averag- 
ing 4'77  dwt.  after  allowing  for  accidentally 
rich  samples.  The  work  on  the  No.  2  level 
has  contributed  one-third  of  the  tonnage  and 
it  is  of  higher  grade  than  that  exposed  on  the 
No.  1  level.  Winzes  below  the  second  level 
make  a  good  showing,  so  that  on  the  whole 
the  mine  never  looked  better.  With  500,000 
shares  quoted  at  £^\%,  the  market  valuation 
stands  at  ;^2,468,500.  The  profit  to  be  ex- 
pected is  about  7s.  6d.  per  ton,  so  that  the  ore 
now  available  represents  a  total  profit  of  about 
^600,000.     The  Shamva  is  a  tall  gamble. 

By  making  liberal  use  of  the  gold  reserve 
the  output  of  the  Globe  &  Phoenix  was  modi- 
fied to  a  degree  possibly  misleading.  In  Sep- 
tember, with  a  reduced  output  and  a  profit  of 
only  ir2700,  an  addition  of  1152  oz.  was  made 
to  the  gold  reserve  ;  in  August,  with  a  larger 
yield,  1687  oz.  was  withdrawn  from  the  re- 
serve, swelling  the  nominal  profit  to;^33,600. 
In  this  and  in  other  cases  it  is  obvious  that 
the  gold  reserve  tends  to  confuse  the  returns. 
Shortage  of  labour  explains  the  diminished 
production  during  September,  the  mill  being 
operated  for  2\\  days  only. 

Both  the  Sheba  and  Pigg's  Peak  are  able 
to  announce  improved  prospects  in  their  an- 
nual reports.  Two  5%  dividends  are  to  be 
paid  by  the  famous  old  mine  at  Barberton. 
At  the  Pigg's  Peak  the  problem  of  ore  treat- 
ment appears  to  have  been  solved,  the  extrac- 
tion having  been  raised  from  50%  two  years 
ago  to  92i%  in  August  last. 

Tanganyika  Concessions  has  suffered  by 
lack  of  information  concerning  the  smelting 
operations,  which  have  now  been  in  progress 
for  several  months.     The  re-assertion  of  opti- 


324 


THE    MINING    MAGAZINE 


mistic  forecasts  is  no  longer  convincing,  and 
it  is  evident  that  even  Mr.  Robert  Williams's 
most  fervid  followers  have  become  timid.  We 
do  not  care  to  harp  on  the  subject,  for  our  criti- 
cisms of  this  enterprise,  published  in  January 
1910,  hold  good. 

A  2s.  dividend  from  the  Lonely  Reef  and 
good  reports  concerning  the  deepest  develop- 
ment in  that  mine  are  pleasing  items  of  Rho- 
desian  news.  On  the  other  hand  the  scarcity 
of  native  labour  is  accentuated  by  a  decrease 
in  the  number  of  stamps  running  at  the  Pen- 
halonga  and  Rezende,  and  the  forecast  of  a 
general  decrease  of  gold  production  during 
the  current  month. 

The  Cam  &  Motor  is  being  boomed,  but  it 
is  a  fine  mine  and  opening  up  extremely  well. 
The  official  statement  is  that  on  September  30 
the  ore  reserve  amounted  to  700,000  tons, 
having  an  assay- value  of  ;/ri,653,000.  A  cor- 
respondent in  Rhodesia  informs  us  that  the 
mine  is  one  of  the  best  and  has  nearly  a 
million  tons  of  ore  developed,  but  some  time 
must  elapse  before  it  can  be  productive,  as 
the  experimental  plant  (a  10-ton  unit)  has 
only  now  been  started.  The  shares  are  quoted 
at  38s.  and  there  are  450,000  of  them,  so  that 
the  market  valuation  stands  at  ;^855,000.  Of 
the  ;^1,653,000  gross  about  ;^750,000  is  likely 
to  be  profit.  The  Eileen  Alannah,  belong- 
ing to  Willoughby's  Consolidated,  adjoins  the 
Cam  &  Motor,  and  covers  a  part  of  the  same 
ore-channel. 

Sir  William  Milton,  the  Governor  of 
Southern  Rhodesia,  has  recently  stated  that 
the  reconstituted  Labour  Bureau  is  to  be  put 

on  a  firm  financial  basis."  Sleeping  sick- 
ness in  Northeastern  Rhodesia  has  now 
diminished  to  such  a  degree  as  to  warrant 
relaxing  the  restrictions  against  recruiting  in 
that  part  of  the  country.  This  improves  the 
prospects  for  an  increased  supply  of  labour. 

West  Africa.— The  gold  output  for  Sep- 
tember is  officially  stated  to  have  been  26,717 
ounces,  valued  at  ;^109,039.  Thus  the  output 


is  slightly  higher  than  in  August  and  is  there- 
fore the  maximum  attained  to  date.  An  in- 
crease is  recorded  by  the  Abosso,  Broomassie, 
Taquah.andPrestea.  Thelast  yielded ;^23, 778 
from  12,945  tons.  As  usual,  the  first  place  is 
held  by  the  Ashanti  Goldfields,  with  an  out- 
put of  ;^40,940  from  12,575  tons  of  ore.  The 
Bibiani  exhibits  a  progressive  decrease.  We 
note  with  pleasure  that  the  Ancobra  Dredging 
Co.  did  much  better  in  September  than  here- 
tofore. 

From  the  Ashanti  Goldfields  comes  the 
news  that  the  Obuasi  ore-shoot  has  been 
found  in  an  easterly  cross-cut  47  ft.  from  the 
No.  8  level  southwest.  The  lode  is  17  ft. 
thick  and  averages  3  oz.  per  ton.  The  per- 
sistence of  this  shoot  greatly  adds  to  the 
value  of  the  property.  The  yield  during 
October  was  9750  oz.,  worth  ^'41,422,  and 
the  profit,  after  every  sort  of  expense  is  in 
eluded,  is  estimated  at  ;^20,095. 

The  report  of  the  Ancobra  Dredging  Com- 
pany outlines  the  plan  of  operations  recom- 
mended by  Mr.  S.  J.  Weis,  the  new  manager. 
It  involves  the  dredging  of  the  old  river- 
channel  instead  of  the  live  stream.  Careful 
drilling  is  to  precede  the  erection  of  a  new 
dredge.  The  scheme  is  well  conceived  and 
in  accord  with  experience  elsewhere. 

The  Rayfield  Syndicate,  with  West  Austra- 
lian associations,  is  now  operating  in  Nigerian 
tin  areas,  and  has  acquired  additional  ground 
of  a  most  promising  character  on  the  advice 
of  Mr.  Walter  Wethered.  The  Nigerian 
Corporation  is  preparing  to  exploit  its  pro- 
perties in  the  Ninkada  area.  Enough  tin  is 
being  obtained  in  the  Bauchi  district  by  '  cal- 
abashing '  or  hand-washing  to  cover  the  cost 
of  the  corporation's  operations  in  Nigeria. 
Mr.  H.  O.  Crighton,  the  manager,  sends 
favourable  reports  in  regard  to  results  from 
prospecting.  Again,  the  Berrida  group  of 
claims,  owned  by  the  Champion  and  Lucky 
Chance  companies  has  been  fa-zourably  in- 
spected   by    Mr.    L.    H.   L.    Huddart,   who 


NOVEMBER,    1911 


325 


considers  that  the  prospects  justify  the  erec- 
tion of  a  pumping-plant  for  the  hydraulicking 
of  the  gravel.  The  area  in  question  covers 
47  square  miles,  of  which  only  49  acres  has 
been  tested  as  yet. 

India.  —  The  chief  shareholders  in  the 
Hutti  (Nizam's)  Gold  Mines  Co.  have  been 
in  consultation  with  the  board  for  the  purpose 
of  deciding  the  best  way  of  raising  the  neces- 
sary capital  for  sinking  a  new  shaft  and  erect- 
ing a  slime-plant.  As  the  company  is  now 
paying  its  way,  owing  to  the  discovery  of  ore 
at  the  1840  ft.  level,  assaying  30  dwt.  over 
3  ft.,  it  was  considered  advisable  to  postpone 
the  decision  until  after  the  general  meeting  to 
be  held  in  December.  Attention  has  been  at- 
tracted to  the  Kolar  group  by  the  announce- 
ment of  interim  dividends,  which  show  that 
the  profits  at  Mysore  and  Nundydroog  are 
substantially  greater  with  the  same  yield  of 
gold.  The  chief  reason  for  this  is  the  recent 
reduction  in  the  price  of  electric  power,  but 
several  other  economies  have  been  effected  by 
improvements  in  hauling  and  hoisting. 

Siberia. — The  recent  \oyage  of  the  bar- 
quentine  Nimrod,  under  command  of  Capt. 
G.  V.  Webster,  from  Liverpool,  through  the 
Arctic  waters  of  the  Kara  sea,  to  the  Yenesei 
and  up  that  river  to  the  interior  of  Siberia,  is 
worthy  of  record.  It  may  be  possible  to  trans- 
port mining  machinery  by  water  ;Erom  England 
to  the  mineral  regions  of  northern  Asia. 

At  the  Spassky  the  output  has  now  grown 
to  340  tons  of  copper  per  month,  the  second 
converter  has  been  started  at  the  smelter,  and 
the  mine  reports  are  fairly  satisfactory.  It 
will  be  noted,  however,  that  the  bottom  level 
exhibits  impoverishment,  and  this  is  to  be  ex- 
pected sooner  or  later,  for  the  Spassky  ore- 
body  affords  a  notable  example  of  secondary 
enrichment.  At  the  Atbasar  the  prospecting 
by  drilling  and  the  development  by  shaft-sink- 
ing tend  fully  to  confirm  the  results  obtained 
from  earlier  bore-holes.  The  problem  of  me- 
tallurgical treatment  is  now  being  carefully 


considered.  Apparently  a  successful  solution 
will  depend  on  the  degree  to  which  the  ore 
can  be  sorted  before  subjecting  the  discard  to 
a  concentrating  process.  The  selected  ore 
will  be  enriched  from  12  to  18%  copper  by 
sorting,  and  will,  of  course,  be  smelted. 

The  Sissert  estate,  on  which  Mr.  Vasili  C. 
Pavlovsky  secured  an  option  recently,  has 
been  taken  over  by  the  firm  of  Gregori 
Benenson  &  Co.  At  present  the  output  is 
at  the  rate  of  125  to  130  tons  of  best  selected 
copper  per  month.  Additional  plant  will  only 
be  installed  after  the  legal  transfer  of  the  pro- 
perty has  been  completed.  No  intention  exists 
to  offer  the  estate  on  the  London  market,  at 
present. 

The  Lena  Goldfields  issues  an  annual  report 
that  must  gratify  the  shareholders.  A  3s.  divi- 
dend is  declared,  making  6s.  per  share  for  the 
year.  The  proceeds  from  shares  in  its  Rus- 
sian subsidiary,  the  Lenskoie,  gave  a  profit 
of  £"519,915,  as  against  a  book-value  of  only 
£68,820.  On  September  30  the  Lena  Gold- 
fields  still  held  67%  of  the  Lenskoie  capital. 
The  Lenskoie  dividendfor  1910  was  ;^313,077. 
That  for  1911  is  yet  to  be  declared.  The  out- 
put of  gold  during  the  year  ending  on  Sep- 
tember 30,  191 1,  was  £■1,619,406  from  881,001 
cubic  yards,  showing  a  yield  of  10  dwt.  per 
yard,  as  against  £"1,551,849  from  748,896  cu. 
yd.,  and  an  average  of  11*4  dwt.  in  1910.  The 
cost  averaged  24'87  shillings  per  cubic  yard, 
as  against  37'61s.  three  years  ago.  Mr.  C. 
M.  Rolker  estimates  the  reserve  at  3,000,000 
cubic  yards  besides  1,676,000  cu.  yd.  of  pro- 
bable pay-gravel.  The  company  is  capitalized 
at  1,405,000  shares,  of  which  1,122,216  are 
issued.  They  are  quoted  at  £"41.  The  Con- 
solidatedGold  Fields  of  South  Africa,  formerly 
a  large  shareholder,  has  liquidated  most  of  its 
holding.  Two  Russian  directors  are  to  join  the 
board,  indicating  the  growth  of  the  Russian 
interest. 

From  Kyshtim  comes  a  sad  item  of  news. 
Horace  H.  Emrich,  formerly  of  Denver,  and 


326 


THE    MINING    MAGAZINE 


a  metallurgist  employed  in  the  copper  refinery 
of  the  Kyshtim  Corporation,  was  shot  through 
the  window  ofhis  house  by  oneof  the  workmen. 
The  cause  is  not  known,  but  it  is  a  dastardly 
crime,  all  the  more  deplorable  as  the  unfortunate 
victim  leaves  a  young  wife  and  two  children. 

Australasia. — Our  Melbourne  correspon- 
dent sends  us  a  clear  account  of  the  labour 
troubles  at  Mount  Lyell.  Smce  he  despatched 
his  letter,  the  engine-men  have  ceased  work. 
This  piece  of  news  is  specially  bad,  because 
it  may  cause  the  flooding  of  the  mine.  We 
understand,  however,  that  Mr.  Robert  Sticht, 
,  manager,  is  confident  of  being  able  to  keep 
the  pumps  going.  The  report  for  the  half- 
year  ended  September  30  discloses  a  profit 
of  /r69,000,  but  under  the  circumstances  the 
directors  decided  tc  distribute  no  dividend. 

The  researches  into  electric  zinc  metallurgy, 
initiated  by  some  of  the  Broken  Hill  com- 
panies, appears  to  have  advanced  to  a  point 
warranting  further  steps.  A  shipment  of  about 
1000  tons  of  typical  ore  is  on  its  way  from 
Broken  Hill  to  Hohenlohe-Hutte,in  Germany, 
and  the  ensuing  tests  are  to  be  made  under  the 
joint  observation  of  F.  W.  Harbord,  H.  W. 
Jepp,  and  A.  E.  Savage.  An  outline  of  the  new 
process  is  given  in  '  Precis  of  Technology.' 
The  dividend  declared  by  the  British  Broken 
Hill  Proprietary  is  the  first  since  1907.  We 
understand  that  the  manager  estimates  that 
fully  2,500,000  tons  of  ore  are  available. 
Better  returns  are  expected  to  warrant  an  in- 
crease of  the  dividend  to  4s.  in  the  case  of  the 
North  mine  and  an  extra  dividend  by  the 
Amalgamated  Zinc  company. 

At  Cloncurry  the  relations  between  the  Mt. 
Elliott  and  Hampden-Cloncurry  companies  are 
becoming  more  friendly,  and  an  amalgamation 
is  likely  to  be  announced  shortly.  Likewise 
the  Oroya  Exploration  and  Lake  View  com- 
panies are  to  be  amalgamated. 

Mexico. — The  Camp  Bird  may  now  be 
definitely  ranged  among  Mexican  issues,  for 
the  revenue  of  the  company  will  henceforth 


come  entirely  from  the  Santa  Gertrudis  mine, 
at  Pachuca.  We  understand  that  400,000 
shares  are  held  in  Paris.  Two  directors  are  to 
be  added  to  the  board  so  as  to  give  French  share- 
holdersarepresentation.  Mr.  J.  H.  Hammond's 
resignation  as  consulting  engineer  is  formally 
announced  as  dating  from  February  last. 

The  Mexico  of  El  Oro  had  a  pleasant  meet- 
ing of  shareholders,  and  the  statement  made 
by  Mr.  Andre  P.  Griffiths,  the  consulting  en- 
gineer, must  have  gratified  those  present.  An 
increased  dividend  was  promised  for  the  next 
quarter,  on  the  basis  of  better  earnings.  A 
gain  of  35,000  tons  in  the  ore  reserve  and 
promising  prospects  on  the  bottom  level  are 
recorded.  The  reserve  of  ore  suffices  to  sup- 
ply the  mill  for  2i  years.  If  this  should  per- 
mit of  dividends  being  paid  for  that  time  at 
the  present  rate  of  16s.  per  annum,  the  total 
return  now  assured  would  represent  40s.  per 
share  on  shares  quoted  at  £l\.  Having  re- 
gard to  the  general  impoverishment  of  the 
lodes  in  the  El  Oro  district  below  the  zone  of 
oxidation,  it  would  appear  that  speculators  in 
Mexico  of  EI  Oro  have  a  robust  confidence  in 
the  future  development  of  the  mine. 

The  300-ton  mill  of  the  San  Francisco  del 
Oro,  at  Parral,has  started  work,  and  is  treating 
dump  ore,  awaiting  the  completion  of  the  aerial 
tramway  from  the  mine.  The  lead  concen- 
trate is  sold  locally,  and  the  zinc  middling  is 
to  be  shipped  to  Trollhattan,  Sweden,  where 
it  will  be  smelted  electrically.  The  Trollhat- 
tan company  has  asked  for  a  product  roasted 
to  4%  sulphur,  instead  of  8%  as  originally  speci- 
fied, so  the  furnaces  are  to  be  modified.  Ap- 
parently there  is  some  difficulty  in  connection 
with  the  roasting  operation,  for  Mr.  John  H. 
Allen,  of  New  York,  has  been  asked  to  give 
his  professional  advice. 

Canada.  —  Our  Toronto  correspondent 
speaks  of  a  revival  of  interest  in  Porcupine. 
We  publish  a  timely  article  by  Mr.  H.  H. 
Johnson,  who  has  recently  returned  from  On- 
tario.    Swastika  appears  to  be  a  promising 


NOVEMBER,    1911 


327 


district,  and  a  favourable  official  report  has 
been  issued  on  another  new  discovery  at  West 
Shining  Tree,  70  miles  north  of  Sudbury. 

The  official  estimate  of  gold  production  in 
the  Yukon  Territory  for  the  past  season,  as 
based  on  the  royalties  received  by  the  Govern- 
ment, is  $4,500,000,  or  about  $250,000  in  ex- 
cess of  last  year.  We  publish  some  notes  on 
dredging  operations  near  Dawson,  in  the  Klon- 
dyke  valley,  by  Mr.  F.  L.  Morris,  who  wrote 
from  the  spot.  It  is  evident  that  the  dredging 
of  frozen  ground  in  the  Arctic  goldfields  has 
been  solved  successfully,  and  that  the  hy- 
draulicking  of  bench  deposits  is  also  profit- 
able, despite  the  shortness  of  the  summer 
season.  The  technical  experience  obtained 
in  the  Yukon  ought  to  be  of  great  service  to 
northern  Siberia. 

A  find  of  gold  ore  is  reported  from  Mani- 
toba on  the  line  of  the  Canadian  Northern 
railway  extension  from  Fort  Alexander.  Capt. 
E.  A.  Pelletier  is  responsible  for  the  pros- 
pecting work  that  led  to  this  new  discovery. 
Only  superficial  tests  have  been  made  as  yet. 

United  States. — Our  New  York  corres- 
pondent sends  an  informing  letter  dealing  with 
the  Steel  Corporation  and  the  Tariff,  two  basic 
factors  in  American  industrial  progress.  In- 
terest in  Alaska  is  increasing,  although  the 
active  season  is  now  closed.  The  Treadwell 
mines  continue  to  do  well  in  depth.  A  dredge 
on  Buck  creek,  not  far  from  Nome,  has  been 
doing  good  work  on  tin  gravel,  extracting 
enough  to  pay  the  first  cost  of  the  plant. 

We  publish  some  interesting  notes  on  dredg- 
ing in  the  Yukon  by  an  engineer  well  versed 
in  this  branch  of  mining,  attention  to  which 
has  also  been  drawn  by  the  interim  report  of 
the  Natomas  Consolidated,  a  Californian  com- 
pany in  which  English  capital  is  interested. 
The  data  afforded  are  not  in  a  form  conveying 
the  information  really  required,  for  the  results 
from  January  1,  1909,  to  June  30,  1911,  are 
lumped  together.  However,  it  is  noteworthy 
that  the  average  cost  of  operating  the  dredges 
5—2 


for  the  first  six  months  of  1911  was  3'78  cents 
per  cubic  yard.  Presumably  this  includes 
wear  and  tear,  together  with  an  allowance  for 
replacement  of  parts.  Dredges  are  perishable 
machines  and  the  cost  of  them  must  be  rapidly 
amortized.  On  such  points  the  report  is  ob- 
scure. The  net  profit  is  given  at  $2,535,537 
for  the  18  months,  on  a  gravel  yielding  9'82 
cents  per  cubic  yard.  It  is  planned  to  have 
14  dredges  in  operation  capable  eventually  of 
digging  27,000,000  cu.  yd.  per  annum. 

As  a  result  of  Mr.  W.  J.  Loring's  visit  to 
the  Mother  Lode  region  of  California,  a  Cali- 
fornia Exploration  Co.  has  been  organized 
by  Bewick,  Moreing  &  Co.,  with  Mr.  Albert 
Burch  as  local  representative.  An  option  has 
been  taken  on  the  Plymouth  Consolidated,  a 
famous  old  mine  in  Amador  county,  idle  since 
1888,  and  1700  feet  deep.  The  mine  is  credited 
with  a  past  production  of  $7,000,000  in  gold. 
It  is  now  being  equipped  preparatory  to  being 
unwatered  and  developed. 

Tin. — We  have  referred  to  the  Nigerian 
mines  and  to  one  in  the  Transvaal.  It  re- 
mains to  chronicle  the  flotation  of  the  South 
Tronoh,  adjacent  to  the  famous  Tronoh,  in 
the  Kinta  valley,  Malay  States.  The  chair- 
man is  Mr.  C.  V.  Thomas  and  among  the 
engineers  reporting  are  Messrs.  Harry  D. 
Griffiths  and  J.  P.  Rowe,  the  present  and 
former  managers  of  the  Tronoh  mine.  It  is 
proposed  to  employ  a  suction-dredge  with  a 
capacity  of  1000  cubic  yards  per  diem. 

The  Malay  tin  mines  controlled  by  Mr. 
James  Wickett  of  Redruth  and  his  circle  of 
friends  in  Cornwall  afford  an  excellent  ex- 
ample of  low  working  cost.  In  the  budget 
of  reports  just  issued  the  Gopeng  is  the  most 
interesting,  for  it  is  highly  profitable.  With 
an  output  of  426  tons  of  tin  concentrate  sell- 
ing for  ^44,788,  the  mining  cost  was  only 
;^14,573  ;  of  the  profit,  ^"24,920  has  been  dis- 
tributed as  dividend  at  the  rate  of  35%,  and 
the  balance  carried  forward  to  swell  the  fund 
required  for  the  extension  of  operations. 


EDITORIAL 


AT  the  last  meeting  of  the  Institution  of 
^Mining  and  Metallurgy  it  was  an- 
nounced that  Mr.  Edward  Hooper  had  been 
selected  as  the  next  president.  This  will  be 
pleasing  news  to  the  members  generally  and 
especially  to  the  many  friends  of  Mr.  Hooper 
in  distant  parts  of  the  world.  The  choice  is 
one  that  will  be  cordially  received,  for  the 
president-elect  is  a  mining  engineer  who  has 
worthily  upheld  the  best  traditions  of  the  pro- 
fession. We  congratulate  him  on  an  honour 
deservedly  won.  His  presidential  address  will, 
we  understand,  be  delivered  before  the  joint 
meeting  of  the  Canadian  Mining  Institute  and 
the  Institution  of  Mining  and  Metallurgy  on 
March  6  at  Toronto. 


M 


EMBERS  of  the  Mining  and  Metal- 
lurgical Club  in  distant  parts  will  be 
glad  to  know  that  the  new  Club  is  doing  well. 
Those  who  reside  in  London  will  not  need  to 
be  told  that  the  Club  is  a  success,  for  they  will 
have  been  impressed  with  that  pleasant  fact 
by  the  attendance  of  members  and  the  general 
convenience  of  the  new  institution.  The  lun- 
cheon hour  brings  together  a  remarkably  re- 
presentative gathering  of  professional  men  and 
others  seriously  engaged  in  mining  or  metal- 
lurgical affairs.  When  the  annual  meeting  is 
convened,  a  new  general  committee  will  be 
elected  for  the  ensuing  year.  Several  mem- 
bers of  the  original  committee  have  been  com- 
pelled to  resign  owing  to  a  change  of  residence 
to  distant  localities.  Others  have  tendered 
their  resignation  with  a  view  to  establishing 
the  principle  of  rotation.  Thus  one-third  of 
the  committee  will  not  offer  themselves  for 
re-election,  although  remaining  in  hearty  ac- 
cord with  the  management  and  retaining  a 
willingness  to  serve  again  after  at  least  one 
year  has  elapsed.   We  take  pleasure  in  making 


note  of  the  fact  that  the  idea  of  rotation  has 
been  put  into  effect,  so  that  the  general  com- 
mittee of  the  Club  will  be  renewed  in  part 
every  year  while  preserving  a  distinct  con- 
tinuity in  its  policy  and  management. 


T 


'HE  death  of  Joseph  Pulitzer  will  have 
served  to  recall  the  fierce  competition 
between  his  paper,  the  New  York  World,  and 
the  Journal  of  W.  R.  Hearst.  The  evil  that 
men  do  lives  after  them.  It  was  bad  enough 
to  have  created  a  newspaper  like  the  World ; 
it  was  worse  to  have  prepared  a  way  for  the 
Journal  and  the  other  journalistic  prostitutes 
which  Hearst  has  scattered  over  the  North 
American  continent.  The  exponents  of  crime 
and  catastrophe  may  have  contributed  to  the 
vividness  and  vivacity  of  American  life,  but 
they  have  effectually  robbed  the  daily  Press 
of  its  moral  influence  and  have  conduced  to 
the  aimless  discontent  and  mental  confusion 
of  a  large  portion  of  the  American  people. 
For  that  we  hate  the  memory  of  Pulitzer  and 
the  name  of  Hearst.  W^e  also  detest  them 
and  their  works  in  that  they  have  spread  their 
evil  contagion  to  the  sober  newspaper  on  this 
side  of  the  Atlantic,  corrupting  standards  of 
old  renown  and  robbing  journalism  of  much 
of  its  former  truth  and  dignity. 


S 


TRATTON'S  INDEPENDENCE  is  a 

mine,  the  history  of  which,  if  faithfully 
related,  would  illustrate  many  of  the  factors 
that  detract  from  the  dignity  of  mining,  for 
the  story  would  include  some  romance,  an  ex- 
cellent sample  of  reckless  finance,  a  good  deal 
of  spoofery,  joined  with  hard  work  and  engi- 
neering skill.  The  last  chapter  is,  on  the 
whole,  the  most  creditable,  for  it  shows  how 
the  mine,  when  on  the  point  of  exhaustion, 
was    resuscitated,    first    by    tributing  under- 


328 


NOVEMBER,    1911 


329 


ground  and  then  by  the  beneficiation  of  the 
old  dumps.  How  that  is  done  is  related  by 
Mr.  Philip  Argall  on  another  page.  It  is 
worthy  of  record  that  this  mine  has  yielded 
$21,061,585  in  20  years,  and  has  paid 
$7,393,656  in  dividends.  The  latter  should 
have  been,  and  would  have  been,  at  least 
$10,000,000  if  the  mine  had  not  been  the 
victim  of  inflated  capitalization  and  of  the 
evils  that  follow  in  its  train.  The  end,  how- 
ever, is  not  yet,  for  the  mine  and  mill  are  still 
producing  at  the  rate  of  $750,000  per  an- 
num. We  trust  that  the  honourable  old  age 
of  this  famous  mineral  discovery  may  be 
peacefully  prolonged,  as  happens  sometimes 
to  men  who  have  had  a  turbulent  past. 


THE  CONTINUED  FALL  in  Tan- 
ganyikas,  or  '  Tanks,'  as  that  heavily 
watered  stock  is  briefly  designated  on  the  Ex- 
change, has  given  rise  to  many  rumours  con- 
cerning the  share-holdings  of  Mr.  Robert 
Williams  and  his  co-directors.  By  reference 
to  the  records  of  Somerset  House  it  would 
appear  that  most  of  these  gentlemen  have 
transferred  large  blocks  of  shares  to  others 
more  willing  to  assume  the  risk.  The  ap- 
pearance may  reflect  a  fact,  but  we  shall  not 
be  in  haste  to  assume  it,  because  it  is  not  neces- 
sary for  anyone  to  hold  shares  in  his  own 
name,  except  in  regard  to  the  small  number 
required  by  law  as  a  qualification  for  director- 
ship. But  we  do  regret  that  the  law  does  not 
forbid  directors  and  other  persons  acting  as 
trustees  from  holding  shares  in  any  name  but 
their  own  and  render  it  a  penal  offence  to 
make  an  arrangement  calculated  to  obscure 
their  exact  financial  participation  in  the  enter- 
prise. Directors  should  be  compelled  to 
adopt  a  frank  attitude  in  this  regard  and  any 
step  likely  to  deceive  those  whom  they  re- 
present— not  their  friends  only,  but  all  the 
shareholders — should  be  regarded  as  a  sinister 
evasion.  By  this  we  do  not  mean  that  direc- 
tors   must    necessarily    be    holders    of    large 


blocks  of  shares  ;  on  the  contrary,  it  is  a  mis- 
take to  assume  that  a  big  speculator  is  the 
best  man  to  control  the  policy  of  a  company, 
save  from  a  purely  speculative  standpoint. 
It  is  desirable,  however,  that  they  should  not 
be  in-and-out  dealers  in  the  shares  of  com- 
panies under  their  direction,  because  that  sub- 
jects them  to  the  obvious  temptation  of  using 
public  trust  for  a  private  purpose. 


West  Africa. 

The  fourth  annual  meeting  of  the  West 
African  Chamber  of  Mines,  under  the  presi- 
dency of  Lord  Harris,  gives  a  clue  to  those 
who  wonder  why  the  mining  industry  of  the 
Gold  Coast  progresses  so  slowly.  Two  fac- 
tors are  prominent,  namely,  high  cost  of  trans- 
port and  inadequacy  of  labour.  We  regret 
to  say  that  the  Government  of  the  Colony  is 
largely  responsible  for  both  of  these  hind- 
rances to  industry.  We  have  before  us  a 
schedule  of  railway  rates,  exhibiting  a  com- 
parison between  the  freight  charges  on  the 
Gold  Coast  Government  Railway  and  the 
South  African  Railways,  as  taken  from  offi- 
cial tariffs.  For  a  distance  of  70  miles  (with 
a  proportionate  increase  for  longer  distances) 
it  costs  24s.  3d.  per  ton  to  carry  beef  in  barrels 
in  South  Africa  and  82s.  6d.  in  West  Africa. 
The  same  rates  hold  for  battery  screening, 
bolts  and  nuts,  and  cyanide.  Chemicals  are 
carried  for  28s.  in  South  Africa  and  133s.  4d. 
in  West  Africa.  The  rate  on  flour  is  13s.  as 
against  82s.  6d.  Preserved  provisions,  24s.  3d. 
as  against  133s.  4d.  per  ton.  Imported  coal 
is  carried  for  16s.  9d.  to  the  Transvaal  and 
for  9s.  6d.  on  the  Gold  Coast.  This  is  one  of 
the  items  in  which  the  West  African  railway 
makes  a  favourable  showing,  for  the  reason 
that  South  Africa  has  coal  mines  and  pre- 
ferential rates  are  given  in  order  to  encourage 
domestic  collieries.  With  this  exception  the 
comparison  indicates  that  the  Gold  Coast  Rail- 
way is  acting  on  the  lines  of  those  American 
railway  managements  whose  motto  is  "  Charge 


330 


THE    MINING    MAGAZINE 


all  that  the  freight  will  bear."  In  his  speech 
Lord  Harris  stated  that  the  earnings  of  the 
Gold  Coast  railway  rose  from  6%  in  1909  to 
9%  in  1910.  The  treasurer  of  that  transport 
system  says  in  his  report  that  "  the  remark- 
able prosperity  of  the  Colony  is  due  largely  co 
agricultural  development."  This  reads  satiri- 
cal to  the  mining  operator  who  realizes  bitterly 
that  his  prosperity  is  not  worthy  of  mention 
and  will  be  unmentionable  until  the  Govern- 
ment adopts  a  more  friendly  attitude.  Turn- 
ing to  the  labour  question,  it  appears  that  the 
Colonial  Office  has  not  met  "  the  reasonable 
wishes  "  of  the  Chamber  of  Mines  as  regards 
the  control  and  supervision  of  natives  em- 
ployed at  the  mines,  for  without  some  system 
of  control  the  effort  to  recruit  a  sufficient  sup- 
ply from  distant  parts  is  doomed  to  failure. 
A  revised  draft  of  the  Masters  and  Servants 
Act  has  been  submitted,  however,  and  it  is 
hoped  that  it  may  be  adopted.  In  these  mat- 
ters we  are  heartily  in  sympathy  with  the 
Chamber  of  Mines,  which  is  acting  in  the 
best  interests  not  only  of  the  mining  com- 
panies but  of  the  Colony. 


Camp  Bird — Santa  Gertrudis. 

The  Camp  Bird  and  its  vigorous  off-shoot 
the  Santa  Gertrudis  have  given  English  share- 
holders a  good  run  for  their  money.  In  these 
days  of  depression  such  a  public  meeting  as 
that  which  marked  the  tenth  annual  gathering 
of  the  shareholders  of  Camp  Bird,  Ltd.,  af- 
fords a  cheerful  commentary  on  the  profitable 
character  of  mining  speculation.  The  chair- 
man, Mr.  Arthur  M.  Grenfell,  had  a  good  ac- 
count to  render,  and  he  rendered  it  with  con- 
fident assurance  that  those  in  the  body  of  the 
hall  would  be  gratified.  In  a  sense,  the  oc- 
casion marked  the  end  of  the  great  mine  in 
Colorado  that  formed  the  basis  of  the  original 
undertaking.  The  Camp  Bird  does  credit  to 
all  concerned,  especially  to  the  late  Thomas 
F.  Walsh,  who  developed  it  from  a  prospect, 
to  Mr.  Frederick  W.  Baker,  who  promoted  the 


English  company,  and  to  Messrs.  John  W. 
Benson  and  William  J.  Cox,  who  successively 
had  charge  of  the  mining  operations.  To  the 
original  owner  the  mine  yielded  ;^900,000  and 
a  profit  of  about  ;^460,000  before  he  sold  it  in 
1902  to  a  company  registered  in  1900.  This 
company  has  nowextracted/^3,750,000  and  has 
distributed  dividends  aggregating  ;^  1,500, 000, 
besides  a  profit  of  ;^300,000  re-invested  in  the 
Santa  Gertrudis.  The  price  paid  for  the  Camp 
Bird  was  ;^1,201,163,  inclusive  of  ;^400,000 
contingent  on  the  profits,  since  paid  in  full. 
The  company  was  capitalized  for  ^1,100,000, 
but  only  820,000  shares  were  first  issued.  The 
original  shareholders  have  received  175%  and 
retain  an  investment  quoted  at  150%  more. 
This  is  one  of  the  handsomest  episodes  in 
Anglo-American  mining.  Nor  is  it  finished  ; 
for  the  Santa  Gertrudis  affords  a  most  promis- 
ing sequel.  In  January  1910  a  controlling  in- 
terest, amounting  now  to  81%,  was  bought  in 
the  Santa  Gertrudis  for  ^922, 131.  According 
to  the  latest  estimate  the  ore  reserve  in  this 
Mexican  mine  stands  at  1,150,000  tons,  from 
which  a  profit  of  ^1,650,000  is  expected. 
During  the  current  financial  year  (to  June  30, 
1912)  the  Santa  Gertrudis  is  expected  to  yield 
a  profit  of  ^200,000,  and  next  year  ir350,000. 
In  the  meanwhile  the  current  earnings  will  in- 
clude ^150,000,  representing  the  last  contri- 
bution from  the  Camp  Bird,  which  will  then 
be  exhausted,  unless  an  unexpected  discovery 
should  prolong  its  life.  Earnings  at  ;^350,000 
per  annum  are  assured  for  5  years  from  the 
ore  already  exposed  in  the  Santa  Gertrudis. 
When  that  is  done  the  capital  invested  will 
have  been  more  than  returned.  Further  bene- 
fits must  depend  upon  the  development  of  this 
mine,  which  has  responded  nobly  to  every  es- 
timate as  yet  made.  It  is  true  the  latest  re- 
port indicates  that  on  the  18th  or  bottom  level 
the  conditions  are  abnormal,  the  large  width 
of  medium-grade  ore  being  replaced  by  a  nar- 
rower lode,  in  two  parts,  one  unusually  rich 
and  the  other  below  the  average  of  the  levels 


NOVEMBER,    1911 


331 


overhead.  This  development  will  be  followed 
with  keen  interest,  for  it  may  presage  a  change 
in  the  character  of  the  orebody.  However,  no 
immediate  cause  for  anxiety  exists,  seeing  that 
the  average  of  the  11  feet  of  ore  on  the  18th 
is  nearly  twice  as  rich  as  that  of  the  ore  ex- 
posed on  the  16th  and  17th  levels.  Taking  it 
all  in  all,  the  Camp  Bird  was  a  highly  credit- 
able mining  issue  and  the  Santa  Gertrudis  has 
the  unquestioned  merit  of  making  money  for 
the  shareholders.  This  it  is  a  pleasure  to  re- 
cognize, but  it  is  our  duty  to  enter  a  friendly 
protest  against  some  of  the  features  of  the 
Santa  Gertrudis  affair.  Thus  the  commissions 
paid  to  the  consulting  engineer,  to  the  direc- 
tors and  their  friends,  reaches  the  lordly  sum 
of  ;^244,178.  At  the  time  the  mine  was  ac- 
quired the  consulting  engineer  and  his  asso- 
ciates received  ;^119,178  for  transferring  the 
option  they  had  secured  on  the  property.  Also 
an  issue  of  280,000  shares  was  guaranteed  for 
2s.  6d.  per  share  by  the  Canadian  Agency,  with 
which  the  chairman  and  another  director  are 
identified.  That  made  ^35,000.  Simultane- 
ously ^500,000  in  debentures  was  underwritten 
for  5%  by  the  Canadian  Agency  and  by  L. 
Hirsch  &  Co.,  with  whom  a  third  director  is 
associated.  That  made  ^25,000  more.  As 
to  this  underwriting  at  the  time  the  mine  was 
purchased,  it  may  be  allowed  that  it  had  to 
be  done  in  a  hurry,  owing  to  the  shortness  of 
the  option,  as  was  fully  explained  by  the  chair- 
man on  December  30,  1910.  Restated  that 
the  time  available  prevented  the  board  from 
going  "tothird  parties."  Theissueof  ;^650,000 
preferred  was  guaranteed  by  the  chairman 
and  his  associates  for  10%,  making  ;£'65,000. 
The  total  is  ^244,178.  Of  course,  all  this 
money  could  not  have  been  saved  in  any  event ; 
some  commissions  had  to  be  paid,  both  on  the 
optional  purchase  and  for  sundry  underwrit- 
ings.  That  is  not  the  point  raised.  We  sub- 
mit that  none  of  it  should  have  gone  to  persons 
employed  by  the  Camp  Bird  company.  None 
of  these  particulars  were  kept  secret.     It  is 


only  fair  to  say  that  the  shareholders  and  the 
public  were  informed  concerning  all  of  them 
even  if  they  did  not  quite  appreciate  them.  If 
they  did,  or  if  they  do,  they  will  most  probably 
take  the  position  that  the  directors  have  given 
them  a  good  run  for  their  money ;  they  have 
had  a  chance  to  buy  shares,  debentures,  and 
preferred  shares  ;  those  who  bought  them  have 
done  well ;  and  if  the  directors  have  made  hand- 
some profits,  so  have  the  shareholders.    Again, 
the  shareholders  will  agree  with  us  that  the 
affair  has  been  managed  with  conspicuous  skill. 
We  refer  to  the  episode  only  to  protest  against 
it  being  accepted  as  a  precedent.  We  hold  that 
directors  are  not  privileged  speculators,  but 
trustees,  representing  not  a  group  or  a  portion 
of  the  shareholders,  but  all  the  shareholders  of 
the  company.  Wecanquotethe  chairman  him- 
self, when  a  well  known  operator  asked  that 
he  and  his  friends  should  have  representation 
on  the  board.     He  said  :  "  I  represent  20,000 
shares,  how  many  do  you  represent  ?  "     Mr. 
Grenfell  replied  :  "  I  represent  820,000  shares 
[all  the  shares  issued  at  that  time] ,  including 
your  20,000."     That  was  a  worthy  answer. 
As  trustees  the  directors   should    not  act  as 
brokers  in  their  own  interest ;  that  seems  ob- 
vious.    The  same  applies  to  a  consulting  en- 
gineer.    We  do  not  question  the  good  faith  of 
any  one  concerned,  but  we  do  insist  that  those 
who  act  in  a  fiduciary  capacity  should  avoid 
an  equivocal  position.     A  man  cannot  serve 
two  masters   when  the  interests  of  these  two 
masters  conflict.     If  directors  are  engaged  in 
underwriting  they  should  not  be  on  the  board 
of  the  company  whose  issues  they  underwrite 
for  a  profit.     If  the  Santa  Gertrudis  had  not 
done    a   bit    better   than    there   was  warrant 
for  expecting,  the  ^244,000  paid  in  sundry 
commissions  would  have  provoked  a  scandal. 
Nothing  of  the  sort  has  happened  ;  hence  the 
subject  can  be  discussed  without  ill-feeling. 
We  place  on  record  this  polite  and  friendly 
protest  in  the  best  interests  of  the  profession 
and  of  the  industry. 


332 


THE    MINING    MAGAZINE 


Prospects  in  Rhodesia. 

It  is  no  misfortune  to  the  mining  industry 
of  Rhodesia   that   the   scribes   who    prepare 
financial  gossip  for  the  daily  Press,  especially 
those  solemn  journals  issued  on  Sundays,  have 
failed  to  create  a  boom  in  Rhodesian  mining 
scrip.     An  untimely  boom  leaves  melancholy 
wreckage.     Conditions  do  not  warrant  an  in- 
flation of  quotations.   Neither  the  labour  situ- 
ation nor  the  condition  of   the  mines  them- 
selves warrants  more  optimism  than  is  already 
rampant.  Several  mines  have  opened  up  excel- 
lently, such  as  the  Shamva,  Lonely  Reef,  and 
Cam  &  Motor,  but  their  satisfactory  develop- 
ment has  in  every  case  been  fully  discounted 
by  a  rapid  rise  in  the  market  valuation.     It 
remains  for  even  the  best  mines  to  fulfil  the 
confident  estimates  already  used  freely  as  a 
basis  for  cheerful  inflation.     To  us  it  appears 
patent  that  the  Rhodesian  operators — and  a 
clever  group  they  are — habitually  put  the  cart 
before  the  horse  ;  they  force  the  market  ahead 
of  the  mine  ;  if  all  goes  well,  the  favourable 
development  has  been  discounted  ;  if  anything 
goes  wrong,  the  public  is  a  melancholy  vic- 
tim.    Another  feature  of  this  market  is  the 
family   party,   whereby    one   company  holds 
shares  in  other  affiliated  enterprises  and  uses 
the  shareholder's  money  in  speculative  pur- 
chases, which  are  supposed  by  the  unwary  to 
represent  public  buying.     We  refer  elsewhere 
to  the  disclosure  of  the  fact  that  several  com- 
panies have  articles  of  association  giving  the 
directors  a  free  hand  in  the  creation  of  share- 
capital.  The  analysis  cf  the  holdings  of  many 
of  the  Rhodesian  companies  exhibits  a  weird 
medley  of  interests  in  diverse  undertakings. 
Others  spread  themselves  in  a  number  of  sub- 
sidiary companies,  the  practical  control  of  the 
entire  group  remaining  in  the  hands  of  one  or 
two  operators  who  find  it  easy,  by  purchases 
or  sales  of  blocks  of  shares  in  the  name  of  a 
company,  to  lift  or  lower  quotations.     This  is 
one  of  the  objections  to  the  group  system. 
The  same  game  has  been  played  on  the  Rand 


ad  nauseam.  We  are  glad  to  note  the  criti- 
cisms with  which  the  recent  Planet-Arcturus 
issue  was  received.  The  report  accompany- 
ing the  prospectus  is  unsigned,  and  therefore 
has  no  value  beyond  the  vague  endorsement 
of  the  Company  that  publishes  it,  namely,  the 
Rhodesian  Exploration  &  Development  Co. 
According  to  the  articles  of  association  "  the 
directors  shall  not  be  under  any  obligation 
before  executing  such  agreements  on  behalf 
of  the  company  to  take  any  steps  to  ascertain 
the  value  of  the  said  claims  and  properties, 
whether  by  local  operations,  independent  in- 
quiry, or  by  other  means,  and  are  hereby  ab- 
solved from  all  further  responsibility  in  regard 
thereto."  This  either  means  nothing  or  it 
means  a  distinct  invasion  of  the  rights  of  the 
proprietary,  that  is,  the  shareholders.  Such 
financial  legerdemain  can  do  nothing  but  harm. 
It  ought  to  put  the  public  on  its  guard  against 
participation  in  a  blind  gamble.  Other  flota- 
tions are  imminent.  We  hope  that  they  also 
will  not  give  cause  for  further  public  protest. 
We  join  in  protesting  because  anything  of 
this  sort  handicaps  the  real  business  of  min- 
ing, which  is  to  make  money  by  exploiting 
ore  deposits,  not  simpletons.  We  turn  there- 
fore with  pleasure  to  the  registration  of  an- 
other development  company,  as  a  subsidiary 
of  the  British  South  Africa  Company.  This 
is  "  to  assist  in  the  more  rapid  development 
of  Rhodesia  '"  and  so  forth.  We  believe  that 
it  may,  despite  Lord  Harris's  sarcastic  refer- 
ence to  the  enterprise  ;  we  believe  in  it,  not 
because  it  is  another  of  the  many  companies 
organized  for  similar  purposes,  but  because 
the  first  directors  are  Messrs,  R.  T.  Bayliss, 
Walter  McDermott,  and  J.  Rochfort  Maguire. 
The  last  of  these  gentlemen  we  know  only  as 
a  vice-president  of  the  Chartered  Company, 
but  the  other  two  have  been  connected  with 
practical  mining  for  a  lifetime.  Our  younger 
readers  may  associate  them  only  with  the 
City  and  its  financial  activities,  but  we  re- 
member when  the  Drumlummon  was  a  famous 


NOVEMBER,    1911 


333 


mine  under  Mr.  Bayliss's  resident  manage- 
ment, and  when  the  Silver  Islet  was  produc- 
ing astonishingly  under  the  technical  care  of 
Mr.  McDermott ;  since  then  their  names  have 
been  associated  with  those  of  other  mines  no 
less  productive,  but  the  early  days  in  Montana 
and  Michigan  gave  both  of  them  the  essential 
grasp  of  mining  that  has  been  fundamental  to 
their  useful  careers.  Apart  from  technology, 
it  is  not  too  much  to  say  that  these  two  new 
Rhodesian  operators  have  passed  through  the 
many  vicissitudes  of  mining  without  detract- 
ing from  their  self-respect  or  from  that  which 
is  willingly  accorded  to  them  by  the  members 
of  the  profession  in  which  they  have  won  a 
commanding  position.  We  are  glad  to  see 
this  new  departure  in  Rhodesia  and  deem 
it  of  the  best  augury  for  the  future  of  that  im- 
portant mining  region. 


Waihi. 

The  regular  reports  from  this  mine  indicate 
that  some  good  ore  has  been  found  at  the  10th 
level  on  the  Empire  lode,  but  no  comprehen- 
sive examination  has  been  made  with  a  view 
to  forecasting  the  future  of  the  mine  or  the 
underlying  causes  of  the  sudden  collapse  that 
reduced  the  market  value  of  the  property  from 
;^2,750,000  to  ^1,500,000.  The  inspection 
made  by  Mr.  G.  A.  Richard,  the  general  man- 
ager of  the  Mt.  Morgan  company,  wholly  failed 
to  meet  the  necessities  of  the  case.  For  this, 
as  we  have  said  before,  the  scientific  study  of 
an  expert  geologist  was  requisite.  It  is  well 
enough  for  the  directors  to  say  that  they  have 
confidence  in  the  local  management.  That  at- 
titude may  please  those  who  are  afraid  that 
their  shares  may  decline  in  value  if  intelligent 
curiosity  be  unduly  sharpened ;  but  it  is  not 
the  attitude  proper  to  men  of  business,  who 
must  face  facts.  The  deterioration  of  the  ore- 
bodies  in  the  Waihi  mine  became  evident  just 
below  the  zone  of  oxidation  and  was  known  at 
the  mine  two  years  ago.  In  August  1910,  the 
Geological  Survey  of  New  Zealand  began  a 


study  of  the  locality,  completing  the  field  ex- 
amination in  March  1911.  Though  the  detailed 
report  is  not  yet  available,  it  is  reasonable  to 
suppose  that  the  local  management  would,  in 
the  ordinary  course  of  events,  obtain  some  idea 
of  the  conclusions  reached  by  the  officers  of  the 
Survey.  If  our  conjecture  be  correct,  then  at 
least  in  March  last  an  inkling  of  the  facts,  as 
they  presented  themselves  to  the  geologists, 
should  have  been  known  to  the  management, 
by  courtesy  of  whom  the  investigation  was 
legally  made  possible.  This  being  so,  why 
was  it  deemed  prudent  to  go  before  the  general 
meeting,  on  May  15,  with  a  report,  which,  for 
the  occasion,  was  hopelessly  incomplete  ?  A 
definite  pronouncement  by  a  geological  expert 
either  confirming  or  contradicting  the  remarks 
concerning  depth  and  impoverishment,  which 
appeared  in  the  manager's  belated  statement 
of  January,  should  have  been  available.  No 
such  expert  statement  being  available,  we  can 
only  come  to  the  conclusion  that  the  directors 
thought  that  the  shareholders  had  been  suffi- 
ciently well  informed,  or  that  the  local  man- 
agement was  not  prepared  to  admit  that  a  geo- 
logical examination  could  bring  to  light  any- 
thing of  value.  The  geological  facts  as  we 
know  them  may  be  briefly  stated. 

The  principal  lode  of  the  Waihi  mine  is  the 
Martha.  This  has  an  outcrop  on  a  hill,  which 
is  the  top  of  an  intrusive  mass  of  dacite  or 
quartz  andesite.  This  hill  is  flanked  by  later 
extrusive  rocks,  in  the  form  of  rhyolite  and 
andesite,  which  fill  the  hollows  of  the  older 
eroded  surface  of  the  dacite.  The  Waihi  lodes 
do  not  penetrate  the  rhyolite  or  the  andesite ; 
they  are  confined  to  the  dacite,  and  their  apex 
is  at  the  old  surface  under  the  younger  rock  for- 
mation. Thus  the  ore-bearing  area  is  limited 
in  one  direction.  This  has  long  been  known. 
Another  limitation,  which  a  geological  examin- 
ation at  any  time  within  the  last  eighteen 
months  would  almost  certainly  have  brought 
to  light,  must  now  be  faced.  Evidence  exists 
that  the  mass  of  dacite  traversed  by  the  pro- 


334 


THE    MINING    MAGAZINE 


ductive  lodes  is  surrounded  by  bedded  flows 
of  dacite  in  which  the  lodes  are  comparatively 
barren,  although  on  Union  hill  some  veins  in 
this  formation  have  been  worked  at  a  profit. 
Not  only  does  the  bedded  dacite  enclose  the 
massive  dacite  in  which  the    rich   orebodies 
exist,  but  the  productive  rock  becomes  con- 
stricted in  depth,  the  formation  converging  un- 
til a  mere  throat  or  vent  is  left  for  the  massive 
dacite.     In  brief,  at  1000  feet  the  productive 
formation  is  rather  small  for  a  mine.     At  that 
horizon  the  bedded  dacite  forms  the  footwall 
of  the  Martha  lode  and  is  adversely  affected 
by  it.     The  contrast  between  the  two  dacites 
is  not  defined,  it  is  confused  ;  not  even  under 
the  microscope  is  the  difference   easily  dis- 
cernible ;  but  the  bedded  rock  has  a  coarser 
texture  and  is  distinguished  by  interbedded 
seams  of  carbonaceous  matter.    For  the  miner 
it  suffices  to  know  that  the  one  rock  has  proved 
favourable  to  the  finding  of  rich  ore  while  the 
other  is  as  distinctly  unfavourable.     Petro- 
graphers  may  furnish  a  reason  for  this  fact ; 
it  is  probable  that  the  cause  is  structural  rather 
than  chemical,  and  due  to  difference  in  time, 
the  massive  rock  being  a  later  phase  of  the 
same  magma  as  that  from  which  the  bedded 
rock  originated.  Although  such  recondite  mat- 
ters may  perplex  a  mine  captain,  it  is  not  too 
much  to  say  that  the  presence  or  absence  of 
oxidation  in  a  lode  should  not  be  beyond  his 
ken.  The  limit  of  oxidation  at  Waihi  is  accom- 
panied by  a  significant  change  :  an  increase  of 
calcite  in  the  ore.     Where  rich,  in  the  zone  of 
oxidation,  the  calcite  is  replaced  by  quartz.  The 
lower  limit  of  oxidation  is  passed  on  the  Martha 
lode  at  about  the  8th  level.     This  fact  should 
in  itself  have  awakened  intelligent  curiosity, 
for,  the  world  over,  the  miner  anticipates  this 
change  with  anxiety.      No  petrographer  or 
geologist  should  be  needed  to  tell  an  experi- 
enced manager  that  when  oxidation    ceases 
to  be  apparent,  and  when   the  composition 
of  his  lode  undergoes   a    change    in    depth, 
that   the   future    of    his   mine    is   at    stake. 


Then  he  requires  expert  advice,  and  he  should 
get  it,  if  he  can  afford  to  pay  for  it.  It  so 
happens  that  the  Waihi  is  one  of  the  relatively 
few  cases  in  which  the  geologist  can  give 
practical  aid  to  the  miner.  That  aid  the 
management  has  neglected  to  obtain,  and 
when  it  is  obtained  it  will  be  in  the  guise  of 
a  delicately  worded  obituary. 


The  Sale  of  Tin. 

During  the  last  six  months  the  price  of  tin 
has   been   maintained  at  an  artificially  high 
range   of  prices   by    the    action    of    what    is 
politely  called  in  the  city  "  certain  Continen- 
tal interests  known  as  the  Syndicate."     The 
producers  of  tin  ores  have  no  reason  to  quarrel 
with  speculative  operations  that  are  incident- 
ally to  their  benefit,  but  on  the  other  hand  the 
consumers  and  the  eventual  users  of  the  mani- 
fold materials  having  tin  in  their  composition 
have  been  hit  hard.     However,  the  case  of 
the  producer  and  consumer  does  not  worry 
the  speculative  middleman,  and  any  re-organi- 
zation of  the  terms  and  conditions  of  the  Metal 
Exchange  contracts  comes  only  from  the  ac- 
tion of  those  members  of  the  Exchange  who 
have  either  been  badly  caught  or  find  that 
their  chance  of  doing  speculative  business  is 
reduced  to  a  minimum  as  long  as  the  Syndi- 
cate retains  its  control  of  all  tin  that  is  offi- 
cially  recognized   in    Metal    Exchange    con- 
tracts.    This  is  the  reason  why  leading  Eng- 
lish firms  have  agitated  for  a  widening  of  the 
scope  of  dealings  in  tin  and  have  succeeded 
in  obtaining  a  new  official  standard  contract. 
It  is  opportune  to  explain  this  matter  further 
for  the  benefit  of  those  who  are  not  familiar 
with  the  method  of  marketing  tin,  and  we  may 
parenthetically  remark  that  the  average  min- 
ing man  and  metallurgist  knows  little  or  noth- 
ing of  the  buffetings  received  by  tin  or  any 
other  metal  between  the  time  it  leaves  the 
smelter  and  the  time  that  it   arrives  at    the 
works  of  the  tin-plate  manufacturer  or  of  the 
makers  of  tin  alloys.     He  is  as  innocent  of 


NOVEMBER,    1911 


333 


the  source  of  all  these  variations  of  price  as 
the  average  lady  of  the  origin  of  the  hobble- 
skirt  or  any  other  vagary  of  fashion.  For  a 
number  of  years  the  only  dealings  officially 
recorded  on  the  London  Metal  Exchange  have 
been  those  in  tin  from  the  Straits  and  Aus- 
tralia. These  supplies  are  represented  by 
the  products  of  the  Penang  and  Singapore 
smelters  belonging  to  the  Straits  Trading 
Company,  and  by  those  from  the  Pyrmont  at 
Sydney,  the  Mount  Bischoff  in  Tasmania,  and 
the  Irvinebank  in  Queensland.  The  tin  pro- 
duced at  these  smelters  comes  from  gravel 
mines  where  a  concentrate  is  obtained  remark- 
ably free  from  other  metals  and  accordingly  is 
of  high  grade,  averaging  99*9%  or  over.  This 
pure  material  is  greatly  in  demand  by  the  tin- 
plate  makers,  who,  in  order  to  secure  a  bright, 
thin,  and  perfect  coating,  find  it  absolutely 
necessary  to  use  nothing  but  the  best  qualities 
obtainable.  We  may  take  it  that  a  large  pro- 
portion of  Straits  and  Australian  tin  is  used  in 
the  manufacture  of  tin-plate.  There  are,  how- 
ever, many  other  producers  of  tin,  and  some 
brands  are  of  equally  high  grade.  The  islands 
of  Banka  and  Billiton,  in  the  Dutch  East 
Indies,  yield  a  quality  even  higher  than  the 
Straits,  averaging  consistently  99'95%.  These 
deposits  are  in  the  hands  of  the  Dutch  Govern- 
ment, which  superintends  the  smelting  and  the 
marketing,  so  that  transactions  in  Banka  and 
Billiton  do  not  come  within  the  scope  of  the 
London  Metal  Exchange.  The  products  of 
the  English,  German,  and  Chinese  smelters 
have  been  debarred  hitherto  from  official  re- 
cognition in  Metal  Exchange  contracts,  and 
they  are  sold  by  private  contract  by  the  smel- 
ters direct  or  through  the  intermediary  of  in- 
dividual members  of  the  Exchange.  The  ores 
from  which  these  brands  are  produced  are  of 
inferior  quality  to  the  Straits  and  Australian 
ores,  and  coming  chiefly  from  lode  mines  con- 
tain other  metals  such  as  iron,  arsenic,  lead, 
antimony,  wolfram,  and  titanium,  some  of 
which  may  be  entirely  eliminated  by  smelting 


and  others  reduced  to  as  low  a  limit  as  is  con- 
sistent with  profitable  operations.  Bolivia  is 
the  largest  producer  of  this  class  of  tin  ore, 
and  those  from  Cornwall  are  of  the  same  type. 
In  our  Precis  of  Technology  we  reprint  a 
table  prepared  for  the  committee  of  the  Lon- 
don Metal  Exchange.  It  shows  that  the  Ger- 
man and  Cornish  brands  are  usually  above 
99%  and  sometimes  approach  99"9%,  and  that 
Chinese  tin  may  contain  so  much  lead  and 
antimony  as  to  bring  the  tin  content  down  to 
95i%.  Most  of  this  quality  of  tin  is  sold  to 
the  manufacturers  of  alloys,  such  as  bronze, 
britannia  metal,  pewter,  and  white  metal. 
These  alloys  are  composed  variously  of  mix- 
tures of  tin  with  copper,  lead,  or  antimony,  so 
that  the  lower  qualities  of  tin  are  as  a  rule  as 
useful  as  the  purer  sorts.  In  addition  to  the 
brands  of  tin  assayed  for  the  committee,  there 
are  many  other  commercial  brands  of  still 
lower  content,  some  having  as  low  a  percent- 
age as  85.  These  are  quite  acceptable  to  alloy 
makers.  Many  of  them  are  made  by  the  lead- 
ing firms,  but  they  are,  of  course,  not  sold 
under  the  same  brand  as  their  standard  quali- 
ties. In  this  connection  it  is  of  interest  to 
note  that  the  two  Cornish  smelting  firms,  the 
Penpoll,  and  Williams,  Harvey  &  Co.  have 
recently  erected  subsidiary  works  near  Liver- 
pool, because  that  locality  is  more  convenient 
for  the  transport  of  Bolivian  ores  and  for  the 
distribution  of  their  products  among  alloy 
makers,  a  third  advantage  being  the  nearer 
proximity  to  the  source  of  fuel. 

Reverting  again  to  the  recent  action  of  the 
Metal  Exchange,  we  have  to  record  that  hence- 
forward any  tin  made  by  the  chief  smelters 
and  refiners  assaying  over  99%  will  be  accepted 
in  fulfilment  of  contracts.  Tin  over  99f% 
will  be  held  to  be  the  '  standard  '  as  regards 
quotations,  and  tin  from  99  to  99f%  will  be 
priced  at  £l  per  ton  less.  In  this  way  any 
dealer  caught  short  will  be  able  to  make  good 
his  contracts  by  delivering  Banka,  Billiton, 
English,  German,  or  Chinese  tin,  subject  to 


336 


THE     MINING     MAGAZINE 


the  limits  above  recited.  At  first  sight  it 
may  be  supposed  by  some  people  that  the 
tin  below  99f%  is  being  unduly  penalized 
and  that  the  mines  and  smelters  will  suffer. 
This  is  not  so,  however,  for  in  all  probability 
the  present  methods  of  disposing  of  tin  will 
suffer  no  interference.  As  a  matter  of  fact, 
the  alteration  in  the  official  contract  will 
make  no  difference  to  the  producer  and  con- 
sumer, except  that  it  will  tend  to  prevent  wild 
fluctuations  in  the  price  and  occasional  corners, 
seeing  that  the  market  operator  will  have  more 
extensive  resources  from  which  to  draw  than 
has  hitherto  been  possible.  Apart  from  mar- 
ket considerations,  we  may  also  say  that  the 
move  is  perfectly  logical.  The  old  contract 
was  quite  out  of  date,  for  other  parts  of  the 
world  are  now  coming  forward  as  producers. 
Bolivia  has  advanced  and  will  continue  to  ad- 
vance, and  South  Africa  and  Nigeria  are  com- 
ing forward.  Then  again  the  so-called  Straits 
and  Australian  tin  has  not  of  recent  years  been 
derived  solely  from  the  near-by  sources.  For 
instance,  the  Mount  Bischoff  smelter  treats 
custom  ores  of  all  sorts  and  qualities,  and  the 
Straits  smelters  receive  ores  from  as  far  away 
as  South  Africa.  Thus  the  name  of  the  smelter 
from  which  the  tin  emanates  is  no  longer  a 
sure  indication  of  the  characteristics  of  the 
metal.  Taking  a  broad  view  of  the  matter 
we  consider  that  market  operators,  mines,  pro- 
ducers, and  consumers  will  equally  benefit  by 
the  new  '  standard  '  contract. 


The  Gold  Fields  Report. 

The  earnings  of  big  holding  companies* 
such  as  the  Consolidated  Gold  Fields  of  South 
Africa,  necessarily  reflect  the  general  pros- 
perity of  the  mining  companies  in  which  they 
retain  an  interest  and  of  the  share  market  in 
which  they  operate.  Owing  to  the  pronounced 
depression  of  the  past  financial  year,  it  was 
expected  that  the  Gold  Fields  would  be  com- 
pelled to  cut  the  half-yearly  dividend  severely, 
but  such  is  not  the  case,  the  reduction  being 


only  5%,  making  the  total  for  the  year  6s.  per 
ordinary  share  as  against  7s.  in  1909-'10 
and  in  i908-'09.  The  shrinkage  in  profits, 
however,  is  relatively  greater,  namely,  from 
;^993,400  to  /'792,900.  Shares  in  com- 
panies have  increased  by  ;^1,250,000;  from 
;^4,057,613  to  ^5,307,204.  No  list  of  assets 
is  given  ;  this  we  regret,  as  the  distribution 
of  such  a  company's  financial  activities  is  a 
valuable  indication  of  the  tread  of  industrial 
expansion.  It  is  stated  that  realizations  have 
taken  place  in  Russian  assets,  and  we  assume 
that  this  refers  to  Lena  Goldfields,  which  re- 
cently soared  to  a  price  amply  justifying  a 
realization.  Owing  to  the  transfer  of  the 
Rhodesian  and  American  holdings  to  sub- 
sidiary development  companies  organized  for 
that  purpose,  the  parent  company's  report 
does  not  give  much  information  on  these 
matters.  The  Consolidated  company's  joint 
managers  at  Johannesburg  give  some  valu- 
able data  as  regards  the  labour  supply.  These 
confirm  the  views  repeatedly  expressed  in  our 
columns,  namely,  that  the  inadequacy  of  the 
supply  is  a  constant  hindrance  to  the  expan- 
sion of  the  industry.  From  July  1910  to 
July  1911  the  crushing  capacity  of  the  mills 
increased  369,967  tons  per  month,  requiring 
an  increase  of  30,000  natives,  but  the  number 
actually  employed  remained  practically  the 
same,  being  181,514  in  July  1910  and  180,898 
in  July  1911.  However,  it  is  claimed  that  the 
recruiting  operations  are  more  satisfactory  and 
that  the  general  efficiency  of  the  native  labour 
has  been  much  improved,  as  is  shown  in  terms 
of  output  per  worker,  and  also  by  the  slight 
decrease  in  working  cost  at  the  mines  of  the 
Gold  Fields  group  despite  the  acknowledged 
shortage  of  labour.  Mr.  C.  D.  Leslie,  as 
superintending  engineer,  gives  information 
concerning  the  effort  made  to  substitute 
machine -drills  for  hand -labour  in  stoping. 
Machines  of  the  hammer  type  are  advocated. 
Special  steel  is  to  be  used.  Three  large  elec- 
trically   driven    air  -  compressors    have   been 


NOVEMBER,    1911 


337 


ordered.  Among  metallurgical  items,  we 
note  the  transfer  of  the  amalgamating  plates 
from  the  stamp-battery  to  the  tube-mill  cir- 
cuit. This  has  been  done  in  two  of  the  big 
mills.  Amalgamation  has  become  a  less  im- 
portant factor,  thereby  diminishing  the  amount 
of  gold  retained  in  the  mill  and  also  reducing 
the  risk  of  loss  by  pilfering.  The  reference 
to  the  company's  holdings  in  West  Africa 
concludes  with  the  significant  statement  that 
"  the  assistance  hoped  for  "  from  the  Colonial 
office  in  regard  to  recruiting  and  the  discipline 
of  native  labourers  has  not  been  forthcoming. 
In  conclusion,  the  report  mentions  oil  interests 
in  Trinidad  and  placer  options  in  Colombia. 
Thus  the  wide  geographical  distribution  of 
the  Consolidated  company's  activities  is  em- 
phasized. This  feature  is  likely  to  be  accen- 
tuated in  the  future,  as  an  effort  is  undoubtedly 
being  made  to  redress  the  declining  value  of 
the  company's  holdings  on  the  Rand  by  en- 
gaging in  new  and  profitable  business  in  other 
countries.  On  the  whole,  the  report  indicates 
a  policy  marked  by  caution,  but  not  lacking  in 
enterprise. 


Cyanidation  in  Colorado. 

On  another  page  we  publish  a  lengthy  and 
detailed  article  on  the  cyanide  practice  of  the 
Stratton's  Independence  mill,  at  Cripple  Creek, 
Colorado.  This  article  is  written  by  "  the  man 
behind  the  gun,"  that  is,  by  the  metallurgical 
engineer  who  designed  both  the  plant  and  the 
method  of  treatment.  The  author,  Mr.  Philip 
Argall,  needs  no  introduction  to  our  readers, 
for  he  is  one  of  the  few  who  not  only  know 
how  to  do  things,  but  also  how  to  describe  them 
when  once  they  are  done.  Cyanidation  is  no 
new  subject  to  him,  and  especially  the  efifec- 
tive  use  of  cyanide  solutions  on  the  ores  of  the 
Cripple  Creek  district.  These,  of  course,  are 
remarkable  on  account  of  the  tellurium  with 
which  the  gold  is  associated.  Ten  years  ago  it 
was  the  local  practice  to  subject  these  sulpho- 
telluride  ores  to  roasting  before  leaching,  not 


so  much  to  drive  off  the  tellurium,  for  gold 
telluride  is  sparingly  soluble  in  cyanide,  but 
to  expedite  the  cyanidation  by  rendering  the 
ores  permeable  to  the  solution.     In  preparing 
the  ore  for  treatment,  it  was  found  advisable 
to  crush  finely,  because  coarsely  crushed  ore 
when  roasted  yielded  particles  of  gold  too  large 
for  rapid  solution ;  on  the  other  hand,  the  coarse 
gold  was  most  amenable   to  amalgamation. 
Thus  the  Golden  Cycle  mill,  erected  in  1907, 
was  designed  to  employ  coarse  crushing  (to  tg 
inch)  followed  by  roasting,  the  roasted  product 
yielding  its  coarse  gold  to  amalgamation  and 
its  fine  gold  to  cyanidation.     At  first  amalga- 
mating plates  were    used,  but    these    subse- 
quently were  replaced  by  blankets,  the  blan- 
keting being  ground  in  amalgamating-pans.  It 
was  also  ascertained  that  the  dehydration  of 
the  quartz  during  roasting  rendered  the  ore 
brittle  and  therefore  easily  pulverized.     This 
scheme  of  treatment  was  well  adapted  to  ores 
of  medium  grade,  as  viewed  locally,  namely, 
about  8  dwt.  per  ton,  but  was  unsuitable  for 
anything  poorer,  on  account  of  the  high  cost 
of  roasting.     Thus  the  old  filling  in  the  mines 
and  the  old  dumps  on  the  surface  could  not  be 
beneficiated.     The  roasting  alone  entailed  a 
cost  of  $r75  per  ton.     Thereupon  further  ex- 
periments were  made  with  a  view  to  sepa- 
rating the  sulpho-tellurides,  representing  only 
3%  of  the  ore,  and  submitting  that  small  part 
of  the  output  to  roasting.  The  concentrate  thus 
eliminated  became  readily  marketable  at  the 
smelters,  so  that  it  underwent  no  further  treat- 
ment at  the  mine.     The  remainder  of  the  ore 
is  crushed  fine  and  concentrated  on  tables,  but 
dilute  cyanide  solution  is  used  in  lieu  of  water. 
Thus  from  the  moment   the   ore    undergoes 
crushing  the  gold  in  it  is  exposed  to  solvent 
action.     The  details  of  this  latest  phase   of 
Colorado  practice  are  given  in  Mr.  Argall's 
article,  describing  the  mill  erected  in  1908  and 
the  successful  work  accomplished  since.     It 
suffices  to  say  that  this  mill  is  paying  10%  on 
the  reduced  capital  of  the  company  by  treating 


338 


THE     MINING     MAGAZINE 


material  thatelsewhere  in  thedistrictof  Cripple 
Creek  is  used  for  ballast,  by  reason  of  old  con- 
tracts for  easement  and  right-of-way,  where- 
by the  railway  company  is  compelled  to  re- 
move '  waste  '  from  the  ore-sorting  sheds.  This 
serves  to  emphasize  the  character  of  the  me- 
tallurgical feat  that  has  put  money  into  the 
pockets  of  British  shareholders  and  afforded  a 
striking  demonstration  of  the  efficiency  of  the 
cyanide  process  when  placed  in  skilful  hands. 


The  Imperial  College  Union. 

On  the  opposite  page  we  reproduce  the 
photograph  of  the  quarters  or  club-house  pro- 
vided for  the  Union  or  consolidation  of  affili- 
ated student  societies  in  the  Imperial  College 
of  Science  and  Technology,  at  South  Ken- 
sington. Primarily  this  will  interest  our 
readers  because  the  Imperial  College  now  in- 
cludes the  Royal  School  of  Mines,  together 
with  the  Royal  College  of  Science  and  Cen- 
tral Technical  College.  In  April  1909  the 
Governors  of  the  Imperial  College  allocated 
a  sum  of  ;^10,000  for  the  purpose  of  erect- 
ing a  building  or  club-house  for  the  student 
organizations,  for  old  students,  and  for  the 
members  of  the  teaching  staff  in  the  three 
constituent  departments.  Subsequently  the 
grant  was  increased  to  ^17,000.  Thereupon 
Sir  Aston  Webb  was  commissioned  to  design 
a  building,  the  erection  of  which  was  com- 
pleted a  year  ago.  In  this  building  provision 
was  made  for  a  restaurant  capable  of  seating 
150  persons,  a  smoking  room  of  equal  size,  a 
library  and  gymnasium,  together  with  two 
smaller  sitting-rooms  for  the  use  of  women 
students  and  professors  respectively.  While, 
as  stated,  the  Governors  provided  the  funds 
for  erecting  the  building,  it  was  left  to  the 
members  and  their  friends  to  raise  the  money 
needed  to  furnish  the  club-house.  This  was 
done  by  making  a  public  appeal  to  old  stu- 
dents of  the  three  schools,  the  hope  being  to 
raise  enough  money  to  complete  the  furnish- 
ing and   also  to  purchase  separate  playing- 


fields.  The  last  item  had  however  to  be 
shelved  for  the  present  as  only  ^1600  was 
subscribed,  that  is,  just  enough  to  purchase 
furniture  and  other  essentials.  But  the  sub- 
scription list  is  not  closed  and  it  is  hoped  that 
further  donations  will  be  forthcoming ;  these 
should  be  sent  to  the  Right  Hon.  Arthur 
Dyke  Acland,  at  the  Imperial  College,  or  to 
Mr.  Arthur  C.  Claudet,  at  6,  Coleman  St., 
E.C.  Graduates  in  distant  countries  will  be 
glad  to  hear  of  the  Union  and  its  quarters, 
and  will,  we  trust,  put  their  hands  in  their 
pockets  effectively.  The  financial  status  of 
the  enterprise  is  sound,  for  to  the  surplus  of 
^700  at  the  bank  may  be  added  an  income  of 
^850  drawn  from  regular  student  subscrip- 
tions, which  are  paid  with  the  fees  for  tuition. 
Thus  the  future  is  assured.  It  remains  to 
tender  hearty  congratulations  to  those  who 
have  worked  loyally  towaid  a  useful  purpose, 
and  among  the  younger  men  we  may  mention 
Mr.  P.  Litherland  Teed,  who  has  earnestly 
represented  the  hopes  and  ambitions  of  the 
student  body.  Old  students  are  invited  to  visit 
the  club  house,  which  is  intended,  among 
other  things,  to  bring  together  present  and 
past  students,  as  well  as  students  and 
teachers,  in  a  common  effort  to  further  the 
highest  ideals  of  a  technical  education. 

On  November  3  the  opening  ceremony  took 
place,  Mr.  G.  S.  M,  Taylor,  as  president  of 
the  Union,  being  in  the  chair.  The  proceed- 
ings began  with  a  charming  and  effective 
speech  by  Sir  Thomas  Holland,  who  was 
followed  by  Mr.  Acland,  to  whom  the  com- 
pletion of  the  enterprise  is  so  largely  due.  A 
spirit  of  co-operation  and  mutual  goodwill  was 
earnestly  expressed,  and  it  was  obvious  that 
those  in  control  of  the  Imperial  College  have 
now  a  confident  expectation  of  bringing  to- 
gether the  discordant  elements  out  of  which 
a  great  educational  institution  has  been  evolv- 
ed. The  unifying  and  consolidating  influence 
of  a  common  meeting-place  for  all  the  stu- 
dents and  staff  was  urgently  needed.     It  has 


NOVEMBER,    1911 


339 


O 


ft; 


340 


THE    MINING    MAGAZINE 


now  been  supplied.  We  hope  that  former 
students  will  visit  the  Union.  We  hope 
also  that  the  next  Royal  School  of  Mines 
dinner  will  be  held  there  and  that  the 
occasion  may  be  used  to  create  further  inter- 
est in  the  undertaking.  It  is  worthy  of 
enthusiastic  support.  We  give  ours  with 
keen  pleasure. 


Impoverishment  in  Depth. 

The  East  Rand  fiasco  continues  to  hold  the 
stage.  Although  we  regret  the  injury  it  has 
done  to  public  confidence,  we  believe  that  the 
only  way  to  turn  the  episode  to  good  account 
is  to  probe  it  to  the  bottom,  in  order  thereby 
to  obtain  such  warning  and  guidance  as  may 
prevent  a  repetition  of  similar  blunders  in  the 
future.  To  make  a  mistake  is  regrettable ; 
to  fail  to  learn  from  mistakes  is  damnable. 
Therefore  we  turn  with  keen  interest  to  a 
letter  in  The  Financial  Times  quoting  (from 
the  Johannesburg  Evening  Chronicle)  the 
evidence  given  in  1907  by  Mr.  Frederick 
Hellmann  before  the  Mining  Industry  Com- 
mission at  Johannesburg.  Mr.  Hellmann  was 
at  that  time  the  general  manager  of  the  East 
Rand  Proprietary.  His  evidence  referred  to 
the  prospects  of  the  big  group  of  mines  under 
his  charge  and  incidentally  to  the  general  ques- 
tion of  impoverishment  of  ore  in  depth  as  it 
affected  the  future  of  the  Rand  mining  indus- 
try. The  evidence  was  given  in  camera  but 
it  was  published  in  a  Blue  Book  and  should 
have  been  known  to  the  directors  of  the  East 
Rand  Proprietary  before  the  consolidated  com- 
pany was  floated  in  1908.  It  argues  that  the 
technical  Press  at  Johannesburg  must  have 
been  curiously  complacent  to  market  opera- 
tors not  to  have  given  publicity  to  testimony 
of  such  importance.  For  we  know  Mr. 
Hellmann  and  his  qualifications  ;  we  there- 
fore do  not  hesitate  to  say  that  we  have  the 
highest  respect  for  his  opinion  on  such  a 
fundamental  question.  In  brief,  he  testified 
that  a  decrease  of  gold  content  was  "  most 


marked  "  in  "  all  the  mines  "  with  which  he 
was  acquainted  on  the  Rand.  Even  in  the 
Driefontein  "  the  poor  zone  was  much  more 
extensive  "  than  he  had  expected.  On  cross- 
examination,  he  said  frankly  :  "  I  refer  to  the 
Rand  generally.  I  have  been  around,  and  I 
know  the  conditions  of  the  deep  levels,  and  I 
can  say  generally  that  you  have  got  a  falling 
grade  in  depth,  and  that  it  is  most  natural  it 
should  be  so.  You  would  expect  it  from  the 
start  from  the  method  of  deposition.  In  depth 
any  mine  gets  poor.  That  is  the  history  of 
every  gold  mine  in  the  world."  In  answering 
Mr.  Cresswell,  he  insisted  on  this  view  and 
told  his  questioner  that  he  also  must  be  aware 
of  it,  despite  any  disclaimer.  Anyhow," 
Mr.  Hellmann  concluded,  "  I  know  it,  and  I 
give  it  as  my  evidence." 

The  obviously  unstudied  manner  of  express- 
ing himself  is  convincing  as  regards  the  sin- 
cerity of  the  witness,  even  to  anyone  ignorant 
of  his  high  reputation  as  an  engineer.  En- 
gineering i?  based  on  the  recognition  of  facts. 
Honest  thinking,  as  well  as  honest  acting,  is 
essential  to  scientific  operations.  Here  we 
have  a  highly  competent  man  saying  what  he 
thinks,  not  recklessly,  but  after  mature  con- 
sideration and  a  fullness  of  experience  amply 
warranting  a  decisive  answer  to  one  of  the 
basic  problems  of  precious-metal  mining.  Yet 
in  March  1910  both  Sir  George  Farrar  and 
Mr.  Lionel  Phillips  testified  to  the  share 
holders  of  the  East  Rand  Proprietary  that  the 
Angelo  Deep  had  '  added  to  the  evidence  that 
the  Witwatersrand  series  were  not  decreasing 
in  value  "  in  depth.  Again,  it  was  stated  by 
Mr.  Phillips  that  "  if  they  excluded  the  sur- 
face area  down  to  200  or  300  feet,  there 
seemed  to  be  no  evidence  whatever  that  the 
gold  contents  at  the  deepest  levels  were  not 
fully  as  high  as  they  were  at  the  surface,  or 
within  300  ft.  of  the  actual  surface."  Mani- 
festly, the  testimony  given  by  Mr.  Hellmann 
must  have  been  known  to  these  gentlemen, 
yet  they  said  that  "  no  evidence  whatever  " 


NOVEMBER,    1911 


341 


existed  to  dispute  their  confident  but  ama- 
teurish statements.  Needless  to  say,  on  such 
a  technical  matter  the  opinion  of  an  experi- 
enced mining  engineer  is  worth  that  of  a  dozen 
directors  and  financiers.  We  are  not  lacking 
in  respect  for  the  ability  and  experience  of 
such  men  as  Sir  George  Farrar  and  Mr. 
Lionel  Phillips  in  business  affairs,  in  politics, 
in  sport,  even  in  warfare,  but  when  it  comes 
to  a  basic  technical  problem  they  are  merely 
intelligent  spectators.  We  are  compelled 
therefore  to  blame  those,  whoever  they  may 
be,  to  whom  is  due  the  concealment  of  Mr. 
Hellmann's  testimony,  and  we  regret  that  a 
very  pardonable  loyalty  should  have  made  it 
proper  for  him  to  withhold  publicity  from  his 
views  on  so  important  a  question.  However, 
the  evidence  has  now  seen  the  light  of  day, 
and  it  remains  to  give  heed  to  it.  Naturally, 
if  we  had  been  aware  of  it  three  months  ago 
when  discussing  the  same  subject  in  connec- 
tion with  Mr.  C.  O.  Schmitt's  paper,  and  Mr. 
H.  F.  Marriott's  discussion  thereof,  we  would 
have  made  appropriate  use  of  such  weighty 
testimony.  We  must  now  reiterate  the  re- 
quest for  a  publication  of  the  evidence  on 
which  Mr.  Marriott  asserted  that  "  the  assay- 
values  of  samples  of  actual  reef-widths  taken 
throughout  all  the  mines,"  of  the  group  con- 
trolled by  the  Central  Mining  Corporation, 
showed  no  substantial  evidence  "  of  general 
deterioration  in  the  richness  of  the  ore  with 
increasing  depth.  It  may  be  asked  why  we 
insist  on  Mr.  Marriott  submitting  detailed 
evidence,  when  we  do  not  demand  it  from 
Mr.  Hellmann,  as  an  earlier  witness.  The 
answer  is  that  impoverishment  in  depth  is  a 
world-wide  fact  ;  the  rule  needs  no  proof  ;  it 
is  the  exception  that  requires  demonstration. 
Such  exceptions  have  been  known  for  a  short 
time  and  for  a  limited  depth,  only  however 
eventually  to  comply  with  general  experience 
and  to  be  proved  local  variants  from  a  rule 
that  is  indelibly  burnt  into  the  memory  of  the 
miner.      The    recognition    of    it    will   do    no 


harm  save  to  irresponsible  finance  and  reck- 
less speculation.  Mining  is  based  on  facts. 
Neither  the  industry  nor  the  public  that  finds 
the  money  for  it  will  suffer  by  smashing  a 
fallacy  that  is  the  first  falsehood  of  the  flam- 
buoyant  promoter  and  the  last  resort  of  the 
perplexed  financier. 


Meticulous  Estimates. 

On  previous  occasions  we  have  referred  to 
the  air  of  precision  imparted  to  estimates, 
necessarily  approximate,  by  giving  them  in 
figures  to  several  decimal  points.  All  esti- 
mates of  ore  in  reserve  underground,  that  is,  ore 
only  visible  and  measurable  in  part,  are  sub- 
ject to  error  within  a  reasonable  limit.  To 
state  the  tonnage  or  the  assay-value  in  units 
suggesting  excessive  accuracy  is  misleading 
to  the  public.  By  experienced  professional 
men  it  is  deemed  merely  absurd.  W^e  ob- 
ject to  it  because  it  is  farcical  and  therefore 
calculated  to  deceive  shareholders.  Not  long 
ago  we  animadverted  on  Mr.  H.  A.  Piper's 
use  of  three  decimals  in  giving  the  penny- 
weight-contents of  the  reser\e  in  the  Globe 
&  Phoenix  gold  mine.  We  note  that  the 
latest  estimate  gives  35728  dwt.  as  "  the  aver- 
age value,"  meaning  thereby  the  average  gold- 
content,  per  ton.  When  engineers  can  esti- 
mate to  a  nicety  expressed  by  one  in  a 
thousand  parts  of  a  pennyweight  of  gold,  we 
shall  be  the  first  to  applaud  their  skill.  At 
present  the  decimal  points  indicate  merely 
the  fact  that  one  quantity  divided  by  another 
has  yielded  a  fractional  quotient.  In  the 
Natomas  interim  report  Mr.  C.  M.  Kolker 
gives  the  average  value  of  dredging  land  in 
California  as  9'9395  cents  per  cubic  yard  and 
the  average  cost  as  4"0889  cents.  We  ask 
whether  his  statement  would  not  be  as  truth- 
ful if  the  value  were  put  down  at  10  cents 
and  the  cost  at  4  cents  ?  Of  course,  neither 
he  nor  any  other  engineer  is  able  to  estimate 
gravel  any  closer  than  in  cents  per  yard  ;  it  is 
merely  pretentious  and  misleading  to  write  or 


342 


THE    MINING    MAGAZINE 


speak  in  minute  subdivisions.  If  the  Nato- 
mas  yields  10-cent  gravel  at  a  cost  of  4  cents 
per  cubic  yard,  as  is  quite  likely,  we  shall  be 
the  first  to  give  Mr.  Rolker  credit  for  an  ac- 
curate estimate.  If,  however,  engineers  will 
persist  in  a.  mock-accuracy  that  disdains  round 
figures  we  shall  not  be  surprised  if  share- 
holders and  the  public  generally  hold  them 
to  estimates  of  a  meticulous  exactitude.  For 
example,  Mr.  Rolker's  estimate  of  January 
1909  gave  the  gross  assay- value  as  9"9395 
cents,  but  the  gravel  actually  dredged  to  June 
30,  1911,  yielded  only  9'8260  cents;  again, 
his  earlier  estimate  gave  4'0889  cents  as  the 
average  cost  but  the  actual  operations  show  a 
cost  of  4"  1 340  cents  per  cubic  yard.  Evidently 
his  estimates  were  in  error  to  the  extent  of 
0"1135  c.  for  the  assay-value,  while  that  of 
cost  was  too  low  by  0'0451  c.  per  cubic  yard. 
This  is  a  most  serious  discrepancy  and  war- 
rants the  appointment  of  a  committee  of  in- 
vestigation !  However,  speaking  seriously, 
we  deem  it  a  pity  that  intelligent  men  like 
Messrs.  Piper  and  Rolker,  for  example,  should 
lend  themselves  to  make-believe  of  any  sort, 
especially  of  a  kind  likely  to  hurt  the  profes- 
sion to  which  they  belong. 


Official  Opinions. 

In  a  series  of  articles  appearing  in  The 
Times  a  well  informed  writer  has  described 
general  conditions  in  Nigeria,  and  has  given 
some  account  of  the  tin  mines.  Incidentally 
he  condemns  "  the  practice  of  Government 
officials  identifying  themselves  with  financial 
syndicates  to  exploit  the  country  they  have 
participated  in  administering."  In  one  case, 
it  is  true,  an  experienced  ex-official  prevented 
a  fraudulent  promotion.  We  agree,  however, 
with  The  Ttuies  that  this  isolated  case  does 
not  lessen  our  dislike  of  an  objectionable  prac- 
tice, which  usually  lends  itself  "  to  impair  the 
very  high  standard  of  public  service  of  which 
Great  Britain  rightly  makes  a  boast.  Indeed, 
our  experience  in  several  of  the  over-seas  Do- 


minions all  goes  to  prove  that  the  less  Govern- 
ment or  State  officials  have  to  say  about  the 
value  of  mines  the  better  for  all  concerned.  It 
is  a  fallacy  to  suppose  that  Wardens,  Inspec- 
tors of  Mines,  Mineral  Surveyors,  Government 
Geologists,  and  the  like,  are  ex  officio  good 
judges  of  mines  from  either  a  speculative  or 
an  investment  point  of  view.  Naturally  they 
are  prejudiced  by  their  desire  to  stimulate 
local  industry  and  by  their  wish  to  aid  local 
owners  or  promoters  of  mines.  It  is  no  part 
of  their  duty  to  express  opinions  on  the  earn- 
ing power  of  commercial  enterprises,  save 
occasionally  to  prevent  a  gross  scandal.  The 
incidental  comment  appearing  in  an  official 
report  should  not  be  rated  as  the  serious  ap- 
praisal of  a  complex  undertaking.  Gratuitous 
opinions  on  mines  are  worth  what  they  cost. 
The  type  of  man  in  the  Government  service 
is  usually  honourable  and  well  intentioned  but 
he  is  rarely  equipped  by  training  or  experience 
for  the  difficult  business  of  mine  valuation. 
When  he  is  not  honourable,  and  merely  lends 
himself  to  unscrupulous  promoters,  he  is  pes- 
tilential. Even  the  scientific  members  of  a 
Government  service,  such  as  the  officers  of  the 
Geological  Survey,  are  rarely  qualified  for  the 
task  to  which  we  refer.  They  have  not  had 
charge  of  mines,  they  may  not  know  how  to 
take  an  accurate  sample,  they  know  little  about 
metallurgical  details,  they  may  ha\'e  ideas, 
usually  optimistic,  on  the  continuity  of  ore  de- 
posits ;  but  such  ideas  are  apt  to  be  detached 
from  the  earning  of  dividends,  which  is  the 
aim  of  practical  mining.  Exceptions  do  exist, 
of  course.  We  would  like  to  name  them.  They 
are  men  who  have  had  a  training  as  mining 
engineers  before  they  joined  the  Government 
service  and  while  in  that  service  they  have 
continued  to  develop  a  proper  appreciation  of 
economic  essentials.  But  in  such  cases  it  is 
the  individual  and  not  the  office  that  makes 
him  a  reliable  appraiser  of  mines.  Finally, 
we  come  to  the  worst  phase  of  a  bad  prac- 
tice, when  even  Administrators  of  Provinces, 


NOVEMBER,    1911 


343 


Governors  of  States,  and  Premiers  of  Colonial 
Governments  undertake  to  express  opinions, 
which,  of  course,  are  eagerly  exploited  by  those 
whose  business  it  is  to  mine  in  the  pocketsof  an 
unwary  public.  The  worst  example  of  that  sort 
of  thing  was  the  wild  utterance  of  the  Premier 
of  Western  Australia,  who  spoke  in  1910  of 
the  Bullfinch  discovery  in  terms  so  exagger- 
ated as  to  precipitate  a  premature  boom  that 
led  to  the  squandering  of  large  sums  of  money, 
the  building  of  an  expensive  branch  railway, 
and  the  flotation  of  companies  that  have  already 
proved  a  scandalous  failure.  That  unsavoury 
episode  should  stand  as  a  warning  and  a  re- 
minder of  the  basic  fact  that  the  only  person 
whose  appraisal  of  a  mine  is  to  be  considered 
seriously  is  a  competent  practitioner  to  whom 
a  fee  or  retainer  has  been  paid  for  makmg  the 
careful  investigation  essential  to  a  trustworthy 
valuation. 


Origin  of  Petroleum. 

Early  this  year,  Mr.  A.  Beeby  Thompson 
contributed  a  valuable  paper  to  the  Institution 
of  Mining  and  Metallurgy  on  the  geographical 
distribution  and  geological  occurrence  of  petro- 
leum throughout  the  world.  He  refrained 
from  entering  into  a  discussion  as  to  its  origin 
and  genesis,  partly  because  he  did  not  wish  to 
make  his  paper  too  lengthy,  and  partly  because 
he  felt  that  he  had  not  sufficient  data  upon 
which  to  found  a  theory.  Many  of  his  auditors 
regretted  that  he  had  omitted  this  part  of  the 
subject,  for  the  double  reason  that  it  would 
have  afforded  an  excellent  subject  of  debate, 
and  that  a  discussion  might  help  to  elucidate 
a  problem  at  present  wrapped  in  the  deepest 
mystery.  The  deficiency  has  been  made  good 
by  Mr.  Eugene  Coste,  of  Canada,  who  pre- 
sented a  highly  combative  paper  at  the  meet- 
ing of  the  Institution  held  last  month.  Mr. 
Coste's  views  on  the  subject  are  well  known, 
for  he  has  been  the  champion  of  the  inorganic 
theory   for  ten  years,  and  we   abstracted  an 

excellent  paper  by  him  in  our  issue  of  Sep- 
5—3 


tember  1909.  Mr.  Coste's  style  of  writing  is 
not  such  as  to  induce  the  full  confidence  of  his 
readers,  for  he  starts  with  the  assumption  that 
the  views  of  his  opponents  and  supporters  of 
the  organic  theory  are  "  fallacies."  This  atti- 
tude is  apt  to  raise  personal  friction  and  to 
remove  the  discussion  from  the  calm  atmos- 
phere that  is  desirable  at  a  geological  debate. 
When  in  a  minority,  it  is  not  advisable  to  pro- 
claim loudly  that  the  opposing  party  is  radi- 
cally wrong.  We  all  remember  the  Irishman 
on  the  jury,  who,  after  arguing  for  hours,  ex- 
claimed :  "  Eleven  more  obstinate  men  I  never 
met  in  my  life."  But  when  we  listened  to 
Mr.  Coste,  his  genial  personality  and  naive 
method  of  diction  removed  any  antagonism  to 
his  style  of  argument  that  might  have  been 
present  in  our  minds,  and  his  audience  wel- 
comed him  as  a  speaker  even  if  they  did  not 
agree  with  his  views.  Accordingly,  the  dis- 
cussion was  friendly  and  sympathetic  ;  con- 
trary argumentswere  urged  in  detail  and  some- 
times forcibly,  but  without  giving  offence. 
The  paper  and  the  discussion  will  afford  Eng- 
lish readers  a  symposium  of  opinions  on  the 
subject  of  the  origin  of  petroleum.  In  addi- 
tion, we  should  advise  a  perusal  of  Mr.  Ray- 
mond S.  Blatchley's  monograph  that  appears 
in  the  Illinois  Geological  Survey's  yearbook, 
as  this  is  perhaps  the  best  balanced  statement 
of  our  present  knowledge.  We  gave  a  short 
precis  of  Mr.  Blatchley's  writings  in  our  issue 
of  April  last. 

For  the  benefit  of  the  general  reader,  it  is 
opportune  to  state  br-efly  the  views  generally 
held  as  to  the  origin  of  petroleum,  and  we  may 
preface  our  remarks  by  saying  that  natural 
conditions  and  phenomena  afford  little  or  no 
clue  to  the  mystery.  The  upholders  of  the 
organic  theory  insist  on  general  principles  that 
as  petroleum  consists  of  organic  compounds  it 
must  have  had  an  organic  origin.  The  word 
'  organic  '  in  chemistry  is  used  to  describe  any 
substance  composed  of  carbon  and  hydrogen, 
with  sometimes  nitrogen,  oxygen,  and  sulphur, 


344 


THE    MINING    MAGAZINE 


and  it  has  been  borrowed  from  the  vocabulary 
of  biology,  for  any  such  compound  was  always 
supposed  to  have  its  origin  in  or  from  a  sub- 
stance forming  part  of  vegetal  or  animal  life. 
Under  such  circumstances  it  was  inadmissible 
to  suppose  that  the  hydrocarbon  compounds 
constituting  petroleum  could  have  any  other 
than  an  organic  source.     The  fact  that  solid, 
liquid,  and  gaseous  hydrocarbons  can  be  pro- 
duced by  the  distillation  under  heat  and  pres- 
sure of  wood  and  coal  was  considered  to  be  a 
corroborative  circumstance,  the  importance  of 
which   was  irrefutable.      The  occurrence  of 
petroleum  geologically  favoured  the  theory, 
for  most  of  it  is  found  in  Tertiary  strata,  and 
therefore  could  have  been  formed  by  the  dis- 
tillation of  the  earlier  coal  deposits.     Then 
again  the  fact  that  the  volatile  constituents 
of  the  original  vegetal  deposits  forming  coal 
have  been  removed  in  varying  degree  may  be 
used  as  evidence  that  some  distillation  has 
taken  place.     A  specific  argument  advanced 
is  that  the  oil-shales  were  formed  by  the  de- 
cay of  vegetal  and  animal  matter  in  muddy 
water.     These  form  the  general  line  of  rea- 
soning adopted  by  the  supporters  of  the  or- 
ganic theory.    On  the  other  hand,  the  evidence 
in  favour  of  the  opposite  view  is  more  specific 
and  detached.     It  is  shown  that  petroleum  is 
found  in  many  other  rocks  than  the  Tertiary ; 
indeed  wells  have  been  sunk  even  in  ancient 
gneisses.    The  number  of  varying  occurrences 
shows  that  the  distribution  of  petroleum   is 
geographical  rather  than  geological.     To  the 
upholders  of  the  inorganic  theory  the  fact  that 
most  of  the  oil  is  found  in  the  sandstones  and 
shales  of  the  Tertiary  period  has  no  bearing 
on  the  question  of  the  ultimate  genesis  of  the 
oil ;  they  argue  that  these  beds  happen  to  act 
as  reservoirs  because  they  are  porous  and  can 
retain  the  oil  by  capillary  absorption  or  be- 
cause they  are  overlain  by  impervious  strata. 
The  most  important  argument,  however,  is 
supplied  by  the  recent  discoveries  of  the  syn- 
thesis of  organic  compounds  from  the  separ- 


ate elements.  As  already  mentioned,  all  or- 
ganic compounds  were  supposed  to  come  from 
living  bodies,  but  this  principle  has  been  up- 
set by  the  manufacture  of  acetylene  by  the 
reaction  of  calcium  carbide  on  water.  It  is 
easily  conceivable  that  carbides  may  be  formed 
at  great  depths  and  that  their  contact  with 
water  will  generate  hydrocarbons  of  all  sorts. 
Directly  this  is  admitted  we  have  a  basis  for 
a  provisional  theory  of  the  inorganic  origin  of 
hydrocarbons.  On  this  assumption,  hydro- 
carbons have  been  continually  formed  from 
the  earliest  geological  ages  and  are  still  being 
formed,  slowly,  it  may  be,  but  steadily  and 
regularly.  Who  knows  but  that  this  reaction 
may  have  been  the  primordial  source  of  all 
organic  compounds  on  the  face  of  the  earth  ? 
The  theory  is  in  harmony  with  the  observa- 
tions of  investigators  who  have  detected  hydro- 
carbon gases  in  volcanic  emanations  ;  and  in- 
cidentally we  may  mention  that  the  contact  of 
sulphurous  and  hydrocarbon  vapours  would 
cause  the  deposits  of  native  sulphur  found 
at  volcanoes  and  elsewhere.  The  inorganic 
theory  does  not  interfere  totally  with  that  of 
organic  origin,  for  the  latter  would  still  hold 
good  as  far  as  a  secondary  and  perhaps  greater 
formation  of  oil  by  distillation  of  coai  is  con- 
cerned. To  all  these  arguments  the  organic 
party  reply  by  asking  whence  came  the  carbon 
that  combined  with  the  metals  to  form  car- 
bides, and  thus  we  arrive  ultimately  at  the 
problem  as  to  whether  the  first  hydrocarbons 
or  organic  compounds  were  produced  by  in- 
organic synthesis,  or  whether  the  formation 
of  the  myriads  of  combinations  of  carbon  with 
hydrogen,  oxygen,  and  nitrogen  was  first  made 
possible  by  the  introduction  of  that  mysterious 
element  '  life  '  into  the  earth.  We  have  re- 
frained from  burdening  our  readers  with  the 
mass  of  evidence  brought  forward  by  both 
sides  in  this  controversy  as  to  the  origin  of 
oil ;  all  we  desire  to  do  is  to  present  the  main 
arguments  in  such  a  way  that  the  average 
man  may  obtain  a  general  idea  of  the  subject. 


SPECIAL   CORRESPONDENCE 


News   from  our  own  Correspondents  at  the  principal  mining  centres 


JOHANNESBURG. 
The  Brakpan  Mine  was  the  subject  of 
an  interesting  visit  on  September  30  by  mem- 
bers of  the  South  African  Institute  of  Engi- 
neers. The  surface  works  consist  of  the  latest 
apphances  for  the  hoisting,  handhng,and  treat- 
ment of  ore.  Everything  with  the  exception 
of  the  air-compressor  is  driven  by  electricity. 
Two  types  of  electric  hoists  are  in  use,  one 
driven  direct  by  a  three-phase  alternating- 
current  motor  for  hoisting  ore,  and  the  other 
driven  on  the  Ward- Leonard  system  for  hoist- 


tinual  trouble,  due  to  breaking  of  cam-shafts. 
This  was  apparently  anticipated,  for  20  stamps 
are  run  in  sets  of  five,  so  that  broken  cam- 
shafts can  be  used  over  again.  The  advan- 
tage of  running  the  stamps  thus  is  hardly  ap- 
parent, seeing  that  from  past  experience  the 
difficulty  cf  getting  the  cam-shafts  to  stand 
the  strain  is  well  known.  The  result  was 
noticeable  at  the  time  of  the  visit,  when  6 
cam-shafts  were  seen  to  be  broken.  In  these 
cases  only  5  stamps,  out  of  each  set  of  10, 
were  running.     The  cyanide   works   contain 


^ 


Sca/e    of  M//es 
Outcrop, 


EASTERN    PORTION    OF    THE  RAND. 


ing  men,  jumpers,  and  timber.  The  latter  is 
supposed  to  ensure  greater  safety,  the  liquid 
controllers  of  the  three-phase  hoist  being  a 
weak  point.  In  both  systems  a  great  deal 
depends  on  the  brakes,  which,  at  the  Brakpan 
mine,  are  of  the  post  type,  operated  by  dead 
weights  and  relieved  by  compressed-air  cylin- 
ders. In  case  the  power,  due  to  a  break-down 
or  thunderstorm,  were  suddenly  cut  off,  the 
brakes  would  have  to  be  depended-on  entirely 
to  prevent  the  skips  getting  out  of  hand — a 
serious  matter,  if  it  so  happened  that  men 
were  being  hoisted  at  the  time.  The  battery 
consists  of  160  stamps,  each  of  about  2000  lb., 
140  of  them  being  driven  by  electric  motors 
in  sets  of  ten,  with  the  result  that  there  is  con- 


examples  of  the  latest  practice.  In  this  de- 
partment was  seen  a  Butters  filter -plant, 
Pachuca  vats,  and  Merrill  filter-presses  as 
opposed  to  the  old  fashioned  extractor-box. 
Although  a  more  complicated  arrangement, 
yet  the  increased  extraction  of  gold  from  the 
ore  should  pay  handsomely  for  the  extra  capi- 
tal cost  and  maintenance.  The  idea  conveyed 
during  the  inspection  of  an  up-to-date  surface 
plant  on  the  Rand  is  that  with  the  increase  of 
labour-saving  appliances,  the  tendency  is  to 
introduce  mechanical  arrangements  of  greater 
and  greater  complexity,  with  the  result  that 
the  capital  expenditure  is  increased  and  the 
cost  of  maintenance  also.  The  relative  in- 
crease of  the  latter  on  the  new  plants  cannot 


345 


346 


THE    MINING    MAGAZINE 


yet  be  ascertained,  but  it  will  be  an  important 
item  in  a  few  years  on  many  of  the  present 
up-to-date  surface  equipments. 

New  Modderfontein. — This  mine  affords 
an  interesting  technical  study,  as  in  all  depart- 
ments it  contains  examples  of  the  latest  prac- 
tice in  gold  mining.     Underground  there  is 
the  combination  of  old  Rand  practice  with 
colliery  methods,  the  latter  consisting  of  the 
sinking  of  a  circular  shaft,  already  down  to  a 
depth  of  588  ft.,  together  with  the  new  '  big- 
block  '   scheme  of  development.      This  big- 
block  system  is  on  an  even  more  extensive 
scale  on  the  adjoining  mine,  the  Modderfon- 
tein B,  where  the  size  of  the  blocks  is  about 
1000  ft.  on  the  dip  by  750  ft.  on  the  strike. 
The  circular  shaft,  in  conjunction  with  me- 
chanical ventilation,  is  an  improvement  on  the 
old  rectangular  shafts,  and,  with  the  use  of 
cages  and  the  hoisting  of  trucks  from  one 
level,  it  will  be  possible  to  increase  the  speed 
of  hoisting.     A  large  shaft-pillar  will  have  to 
be  left.     The  cost  of  sinking  is  apparently 
greater  than  that  of  rectangular  shafts.     The 
new  '  big-block  '  scheme  of  development  is  an 
innovation,  the  advantage  of  which  has  yet  to 
be  proved.     It  will  be  interesting  to  see  how 
the  estimated  ore  reserves  will  agree  with  what 
is  actually  obtained.   Assuming  that  the  large 
1000  by  750  ft.  blocks  are  worked  on  a  modi- 
fied long-wall  system,  it  is  difficult  to  see  how 
a  face  1000  ft.  long  will  be  kept  in  good  shape 
for  efficient  stoping,  when  numerous  dikes  and 
faults  may  be  encountered  and  also  areas  of 
unprofitable  ground,   which   will  necessitate 
intermediate   drifts   to   cut  large  pillars   for 
safety  and  other  purposes.      The  conditions 
under  which  the  ground  is  broken  in  a  stope 
on  this  goldfield,  where  high  explosives  are 
used,   scattering  the    broken  ore  over  large 
areas  and  making  it  difficult  to  pack  waste 
close  to  the  face,  are  altogether  different  from 
those  obtaining  at  a  long-wall  face  in  a  col- 
liery, where,  for  example,   coal-cutting  ma- 
chines are  used,  waste  being  packed  close  to 
the  face,  the  coal  being  merely  broken  down, 
without  but  little   scattering  action.     These 
new  methods  underground  must  therefore  be 
regarded  in  the  light  of  an  experiment,  and  it 
seems  possible  that  several  modifications  will 
eventually   be  adopted.      As   to    the  mining 
policy  adopted  at  the  New   Modderfontein, 
the  chairman  at  the  general  meeting  of  the 
company  stated   that    neither   the   '  selective 
method '    nor   the    '  wholesale    method '    was 
strictly  adhered  to,  but  it  would  appear  that 
the  former  method  was  in  favour  during  the 
past  year,  as  although  the  working  cost  per 


ton  milled  increased  from  15s.  lOd.  to  17s.  4d., 
the  recovery  value  of  the  ore  also  increased 
from  26s.  4d.  to  28s.  6d.  per  ton.  As  to  the 
surface  arrangements,  a  Butters  filter-plant 
has  been  installed  and  the  important  point  of 
providing  accommodation  for  the  married  em- 
ployees has  received  careful  attention. 

[Our  correspondent's  view  that  the  increase 
in  yield  and  cost  prove  the  adoption  of  the 
selective  method  is  not  confirmed  by  the  re- 
port of  the  directors  and  engineers.  The  rea- 
son for  the  greater  yield  is  officially  stated  to 
be  the  discovery  of  much  high-grade  ore  in 
the  eastern  part  of  the  mine,  while  the  extra 
cost  is  attributed  to  the  amount  of  money 
spent  in  improving  the  methods  of  developing 
and  handling  the  ore  and  to  the  large  amount 
of  development  work  done.  Details  with  re- 
gard to  this  matter  will  be  found  in  other 
pages  of  this  issue,  in  the  abstracts  of  com- 
pany reports,  and  in  the  reports  of  company 
meetings. — Editor]  . 

The  East  Rand  Proprietary  commission 
of  enquiry  was  appointed  in  somewhat  of  a 
hurry  and  regardless  of  the  existing  laws  on 
the  subject.     The  Government  took  it  upon 
themselves  to  appoint  a  commission  of  three 
members,  of  which  the  Government  Mining 
Engineer  was  one,  without  the  necessary  ap- 
plication to  do  so  from  shareholders  holding 
at  least  one-tenth  of  the  total  number  of  shares. 
The  mining  company  fought  the  case  and  as 
a  result  the   Government   has  cancelled  the 
appointment  of  the  first  commission  on  the 
understanding  that  an  application  for  a  com- 
mission  of   enquiry   shall   come  from  share- 
holders holding  the  requisite  number  of  shares, 
petitioning  that  an  enquiry  shall  be  held  to 
look  into  the  affairs  of   the  company.     The 
directors  of  the  company  have  agreed  to  this. 
It  is  difficult  to  see  what  the  commission  will 
be  able  to  discover  wrong  in  the  running  of 
the  East  Rand  Proprietary  mining  group,  ex- 
cept that  it  has  been  found  impossible  to  keep 
up  a  profit,  which  was  estimated  at  too  high 
a  figure  in  the  first  instance,  and  in  the  mean- 
time as  the  grade  of  the  mine   has  not  im- 
proved the  profit  has  of  necessity  to  be  reduced. 
Rand  Water  Board. — The  increased  de- 
mand by  the  mines  for  water  from  the  muni- 
cipal supply  has  risen  from   1*03  million  gal- 
lons per  day  m   July    1909,   to  4'99  million 
gallons  per  day  in  July  1911,  with  the  result 
that  the  Board  found  themselves  supplying  to 
their  consumers  O'l  million  gallons  more  than 
they  were  obtaining  from  all  their  sources  of 
supply.     The  mines  at  present  have  therefore 
to  economize  as  much  as  possible  in  this  direc- 


NOVEMBER,    1911 


347 


tion.  The  tonnage  milled  on  the  Rand  in  July 
1909  was  1,785,450,  against  2,095,220  milled 
in  July  1911,  an  increase  of  309,770  tons  per 
month.  In  July  1909  the  water  supplied  by 
the  Rand  Water  Board  was  being  consumed 
at  the  rate  of  about  18  gallons  per  ton  milled, 
whereas  the  water  supplied  in  July  1911  was 
being  consumed  at  the  rate  of  about  70  gallons 
per  ton  milled.  Apart  from  the  fact  that  the 
tonnage  milled  per  month  has  increased  in  the 
last  two  years  by  309,770  tons,  more  water 
being  naturally  required  for  that  reason,  there 
is  still  the  increased  quantity  per  ton  milled 


and  prevent  the  overflow  of  pulp.  It  is  there- 
fore probable  that  for  the  future  the  amount 
of  water  used  per  ton  milled  will  not  increase 
at  the  same  rate.  As  the  old-fashioned  plants 
die  out  and  newer  ones  take  their  place,  a 
saving  Jn  water  should  result. 

White  Labour. — The  frequent  changes 
among  the  white  workers  on  the  mines  of  the 
Rand  is  a  subject  that  has  been  discussed 
by  Dr.  Donald  MacAulay,  and  admitted  by 
Lionel  Phillips.  The  managers  of  the  mines 
are  blamed  for  this  instability  of  employment. 
As  it  affects  the  managers  equally  with  the 


TAILING-ELEVATOR    AND    CYANIDE    VATS   AT    THE    CITY   DEEP    MINE. 


to  be  accounted  for.  During  the  year  1910 
the  average  quantity  of  water  used  was  about 
330  gallons  per  ton  milled,  while  in  1911  the 
quantity  has  risen  to  about  530  gallons,  of 
which  the  Water  Board  supplies  about  12%. 
The  increase  is  due  in  a  measure  to  a  greater 
consumption  for  domestic  purposes,  but  is 
chiefly  traceable  to  coarse  crushing  by  stamps, 
in  conjunction  with  secondary  crushing  by 
tube-mills.  In  many  mines  tube-mills  have 
been  added  where  the  arrangement  of  the 
original  milling  plant  has  been  unsuited  for 
them  ;  this  applies  chiefly  to  the  original  mill- 
launders,  the  fall  of  which  was  sufficient  for 
the  flow  of  pulp  passing  through  screens  of 
small  mesh,  but  insufficient  for  transporting 
pulp  that  has  passed  through  the  coarser 
screens  now  used.  To  overcome  this  diffi- 
culty more  water  is  used  to  flush  out  launders 


rest  of  the  personnel  of  the  mines,  it  is  wrong 
to  place  the  blame  on  them,  for  the  managers 
are  just  as  uncertain  of  retaining  their  posi- 
tions as  are  their  subordinates.  The  shifting 
usually  begins  with  a  change  in  consulting 
engineers,  who  appoint  their  own  managers. 
The  managers,  in  their  turn,  are  anxious,  as 
are  also  the  consulting  engineers,  to  make  a 
name  for  themselves  by  running  the  mines  to 
best  advantage  and,  in  so  doing,  to  obtain  the 
best  results  for  the  shareholders.  No  group 
of  mines  nor  any  single  mine  can  be  run  by 
one  man  alone  ;  the  results  obtained  depend 
on  the  ability  and  esprit  de  corps  of  all  em- 
ployed. When  new  consulting  engineers  are 
appointed,  if  they  come  from  other  parts  of 
the  world,  they  naturally  bring  their  own  men, 
from  their  own  districts  ;  if,  on  the  other  hand, 
they  are  men   who   have   worked  their  way 


348 


THE    MINING    MAGAZINE 


locally,  they  will  appoint  local  men,  of  whose 
trustworthiness  they  are  certain.  In  turn  the 
subordinates  introduce  their  own  men,  and 
thus  a  change  among  those  at  the  head  of  af- 
fairs is  reflected  throughout  the  ranks  of  white 
employees,  even  to  the  unskilled  labourers. 
Changes  in  the  personnel  of  a  mine  or  a  group 
of  mines  may  or  may  not  lead  to  more  efficient 
working.  Employees  who  have  held  positions 
for  long  periods  may  have  got  into  grooves, 
whereas  it  is  usual  for  "  a  new  broom  to  sweep 
clean."  The  advantages  of  a  change  in  man- 
agement depend  entirely  on  the  judgment  used 
in  making  such  changes.  Instability  militates 
against  the  continuity  of  a  definite  policy,  but 
on  the  other  hand  when  there  is  the  possibility 
of  promotion  there  is  greater  keenness  among 
employees,  provided  promotion  is  known  to  go 
by  merit. 

The  Tailing- Wheel  is  becoming  a  thing 
of  the  past,  its  place  being  taken  by  centri- 
fugal pumps  chiefly  of  the  Robeson- Davidson 
type.  It  often  appears  that,  in  the  laying  out 
of  a  mine,  fashion  is  followed  regardless  of 
any  assured  improvement.  Much  money 
might  be  saved  if  the  older  mines  were  re- 
garded as  experimental  works  from  which 
sound  deductions  may  be  derived  as  to  the 
relative  merits  of  various  appliances  for  doing 
the  same  work.  A  case  in  point  is  that  of  the 
increased  use  of  the  centrifugal  pump  instead 
of  the  tailing-wheel  for  elevating  mill-pulp. 
The  advantages  of  the  tailing-wheel  are  its 
low  working  cost,  slow  speed,  and  saving  of 
power  required  to  elevate  the  pulp  ;  against 
this  we  have  its  high  first  cost.  In  these  days 
when  everything  is  driven  by  electricity,  if  the 
power  goes  off,  no  matter  whether  pumps  or 
tailing-wheel  are  used,  a  stoppage  will  ensue. 
A  tailing-wheel,  with  a  pump  as  a  stand-by, 
is  the  most  efficient  means  of  elevating  mill- 
pulp  up  to  the  usual  heights  required,  of  about 
50  ft.,  as  it  will  use  about  50%  less  power  than 
a  centrifugal  pump  to  do  the  same  amount  of 
useful  work,  apart  from  the  question  of  main- 
tenance. A  tailing-wheel  of  the  latest  pattern, 
55  ft.  diam.,  has  been  erected  at  the  Roode- 
poort  United  Main  Reef ;  thisis  builtof  steel,  on 
the  principle  of  the  bicycle  wheel,  and  is  driven 
by  a  50  hp.  motor,  through  the  necessary  gear- 
ing, to  reduce  the  speed  to  the  required  limit. 

[The  inspectors  finally  appointed  to  investi- 
gate the  East  Rand  affair  are  Harry  O.  Buckle, 
a  chief  magistrate,  P.  Ross  Frames,  managing 
director  of  the  Premier  diamond  mine,  and  R. 
N.  Kotze,  the  Government  Mining  Engineer. 
Their  report  ought  to  be  published  during  the 
current  month. — Editor]  . 


SAN  FRANCISCO. 

American  Institute. — The  topic  of  great- 
est interest  on  the  Pacific  Coast  during  Octo- 
ber was  the  visit  of  the  American  Institute  of 
Mining  Engineers  to  California.  The  \'isiting 
delegates  were  first  entertained  at  Los  Angeles 
and  visited  the  adjacent  oilfields.  At  San  Fran- 
ciscoseveral  technical  sessions  were  held,  which 
were  enlivened  by  an  all-day  visit  to  the  dredg- 
ing operations  of  the  Natomas  Consolidated  at 
Folsom  and  a  Sunday  spent  at  the  famous  Bo- 
hemian Grove,  where  an  outdoorluncheon,  fol- 
lowed by  a  concert,  was  enjoyed.  On  Monday, 
October  16,  the  local  members  of  the  Mining 
and  Metallurgical  Society  of  America  enter- 
tained the  visiting  members  and  distinguished 
guests  at  dinner  at  the  Fairmont  hotel.  The 
dinner  was  followed  by  a  discussion  of  the 
Alaskan  land  laws,  H.  Foster  Bain  being  the 
chief  speaker  ;  in  the  subsequent  discussion  R. 
W.  Raymond,  George  Otis  Smith,  E.  W. 
Parker,  W.  R.  Ingalls,  Charles  G.  Yale,  M. 
L.  Requa,  W.  C.  Ralston,  R.  Kanda,  and  W. 
L.  Saunders  joined.  On  October  17,  mem- 
bers of  the  Institute  and  friends  to  the  number 
of  80  sailed  for  Japan,  where  they  will  be  the 
guests  of  the  Japanese  Mine-owners  Associa- 
tion, returning  to  San  Francisco  on  December 
7.  The  meeting  was  one  of  the  most  inter- 
esting and  successful  in  recent  years. 

Smelter  Fume. — A  novel  method  of  deal- 
ing with  the  sulphur  dioxide  in  smelter  fume 
has  been  suggested  by  Stewart  W,  Young  of 
Stanford  University.  The  copper  ores  smelted 
in  Shasta  county  are  of  such  a  character  that 
the  smeltingcharge  is  nearly  one-third  sulphur. 
Needless  to  say,  the  escaping  fume  has  a  high 
sulphurous  content  and  in  the  moist  climate 
of  the  mountain  valleys  has  a  corresponding 
effect  on  vegetation.  The  method  elsewhere 
followed  of  manufacturing  sulphuric  acid  from 
the  escaping  gases  is  scarcely  applicable,  as 
none  of  the  smelting  plants  is  of  large  enough 
size  to  manufacture  a  by-product  at  a  profit, 
and,  in  addition,  the  acid  works  already  in  oper- 
ation near  San  Francisco  are  already  adequate 
to  supply  the  present  demand.  Mr.  Young 
proposes  to  reduce  the  SO  2  to  S  by  means  of 
crude  oil,  using  calcium  sulphide  as  the  inter- 
mediary. The  difficulties  which  are  likely  to 
present  themselves  in  the  carrying  out  of  this 
process  are  obvious;  the  likelihood  that  the 
calcium  sulphite,  which  is  to  be  converted 
into  calcium  sulphide  by  the  SO 2  and  back  to 
calcium  sulphide  by  heating  with  crude  petro- 
leum, will  become  inactive  after  a  short  period 
of  use,  and  the  danger  that  the  cost  of  reduc- 
tion will  out-weigh  the  advantage  gained,  to 


NOVEMBER,    1911 


349 


name  but  two,  are  likely  to  prove  too  high 
stiles  for  the  new  process  to  get  over. 

Oil.  — M.  L.  Requa,  at  the  San  Fran- 
cisco meeting  of  the  American  Institute  of 
Mining  Engineers,  strongly  urged  the  govern- 
mental control  of  oil  production.  He  asserts 
that  oil  is  now  being  so  recklessly  produced 
that  no  adequate  market  can  be  secured  for  it, 
much  of  it  is  wasted  and  the  rest  is  sold  at  a 
rate  which  yields  only  a  small  return  to  the 
producers.  The  mineral  wealth  of  California 
is  thus  squandered  and  that  commonwealth 
suffers  to  benefit  adjacent  districts. 

C.  W.  Hayes  has  resigned  as  chief  geologist 
for  the  United  States  Geological  Survey  to 
take  charge  of  the  Mexican  oil  interests  con- 
trolled by  Lord  Cowdray.     Mr.  Hayes  is  a 


TORONTO. 

Porcupine. — After  a  long  period  of  de- 
pression there  has  latterly  been  a  pronounced 
revival  of  activity  in  several  of  the  Porcupine 
issues.  Hollinger,  which  leads  the  market,  is 
selling  at  over  $12.  Preston  East  Dome,  one 
of  the  cheaper  stocks,  has  been  greatly  in  de- 
mand, a  very  rich  find  having  been  reported 
on  the  Brydges  claim  immediately  adjoining, 
now  known  as  the  Little  Pet.  The  principal 
interest,  however,  centres  in  the  Dome  and 
Dome  Extension  properties,  owing  to  the 
large  scale  on  which  their  plants  are  being 
constructed.  Both  have  nearly  finished  their 
permanent  buildings,  which  are  most  substan- 
tially built  of  cement,  brick,  and  steel.  Both 
companies  have  well -equipped  independent 


PROSPECTING    AT    SWASTIKA. 


geologist  and  explorer  of  proved  ability  and 
has  done  notable  work  as  an  executive.  The 
position  left  vacant  by  his  resignation  has  been 
offered  to  Alfred  H.  Brooks,  who  has  been  in 
charge  of  the  Survey's  work  in  Alaska,  but 
Mr.  Brooks  so  strongly  prefers  to  continue 
his  work  in  Alaska  that  he  will  remain  in  his 
present  position.  [We  heartily  congratulate 
Alaska  on  this  decision. — Editor]  . 

The  Utah  Copper  Co.  now  has  the  Bingham 
&  Garfield  railroad  in  operation,  and  is  ship- 
ping 11,000  tons  per  day  over  the  line.  A 
compromise  has  been  effected  with  the  Rio 
Grande,  which  claimed  that  it  had  an  exclu- 
sive contract  with  the  Utah  Copper  Co.  for 
handling  its  ore,  and  the  two  roads  will  co- 
operate, as  the  Rio  Grande  is  now  handling 
cars  for  the  Bingham  &  Garfield. 


power-plants,  so  that  in  case  of  failure  of  the 
supply  of  electric  power  from  the  Mattagami 
river,  which  will  shortly  be  available,  no  such 
stoppage  as  interfered  with  the  operations  at 
Cobalt  this  spring  need  be  feared.  Drills  are 
being  used  to  test  at  depth  the  rich  \ein  found 
on  the  surface  at  the  Dome  known  as  the 
Golden  Side-walk  and  it  is  currently  reported 
that  it  has  been  found  at  500  ft.  The  Dome 
Extension  is  also  drilling  to  tap  this  deposit 
at  depth,  and  has  resumed  work  on  its  main 
shaft.  At  the  West  Dome  the  ridge  extend- 
ing from  the  Dome  property  is  being  tested 
by  core-drilling.  Four  shafts  will  shortly  be 
put  down.  Steady  development  work  on  the 
Rea  has  resulted  in  the  blocking-out  of  a  large 
amount  of  ore.  The  main  shaft  is  down  nearly 
300  ft.  and  is  connected  with  shaft  No.  2  at 


350 


THE    MINING    MAGAZINE 


the  200-ft.  level.  The  mam  vein,  which  has 
been  uncovered  for  400  ft.,  is  from  12  to  20  ft. 
wide.  Harold  Kingsmill,  late  manager,  has 
resigned  to  go  to  South  America.  The  Crown 
Chartered  has  begun  development  work  on 
the  Davidson  claims.  The  Scottish  Cobalt 
has  been  transferred  to  the  Scottish  Ontario 
company  representing  British  interests  capi- 
talized at  $1,000,000.  It  is  planned  to  install 
improved  machinery  and  work  on  a  large 
scale.  The  Hollinger  has  completed  over 
1100  ft.  of  driving  and  is  putting  down  a 
double-compartment  shaft  to  500  ft.  to  con- 
nect all  the  underground  workings,  operations 
having  been  delayed  considerably  by  the  diffi- 
culty in  transporting  materials.  The  Dobie 
has  cut  the  main  vein  at  55  ft.  in  the  shaft. 
George  E.  Parish  has  been  appointed  manager 
in  place  of  Charles  E.  Watson,  who  goes  to 
the  Plenaurum  in  the  same  capacity,  the  con- 
trol of  the  two  mines  being  largely  identical. 
The  Pearl  Lake,  having  obtained  excellent 
assays  from  a  deep  drill-core,  will  sink  the 
main  shaft  to  400  ft.  The  Mclntyre  has 
ordered  a  40-stamp  mill  and  is  putting  down 
five  shafts.  Good  ore  is  being  mined  on  the 
100-ft.  level.  The  Vipond  has  ordered  a  mill 
of  100  tons  capacity.  The  Eldorado  has  struck 
a  rich  vein  in  the  shaft  at  30  ft.  Operations 
on  the  Success  have  been  suspended. 

The  Swastika  district,  on  the  line  of  the 
Temiskaming  &  North  Ontario  Railway  about 
65  miles  east  of  Porcupine,  is  rapidly  coming 
into  prominence.  There  are  now  about  3000 
people  in  this  area,  a  large  proportion  of  them 
being  Americans.  The  principal  mine  is  the 
Swastika,  where  a  large  amount  of  develop- 
ment has  been  done.  It  has  installed  a  12- 
drill  compressor  and  machinery  sufficient  to 
accomplish  600  ft.  per  month  of  underground 
work.  The  Homestead  is  a  recent  flotation 
capitalized  at  $2,0t>0,000  and  operating  a  pro- 
perty of  78  acres  on  which  an  adit  has  been 
driven  into  the  hillside  for  75  ft.  The  Pike 
Lake  has  started  sinking  on  a  40  ft.  lode 
carrying  free  gold.  At  the  Lucky  Cross  a 
shaft  is  being  put  down  by  hand  until  the 
compressor,  now  in  course  of  erection,  is 
ready. 

Cobalt. — Little  attention  is  being  paid  to 
Cobalt,  the  market  continuing  featureless  in 
the  absence  of  important  developments.  Ship- 
ments from  the  producing  mines  are  well  main- 
tained. The  Beaver  made  a  good  strike  last 
month,  when  a  new  vein  carrying  high-grade 
ore,  8  in.  wide,  was  cut  in  driving  from  the 
350  level  of  No.  5.  The  main  shaft  of  the 
Temiskaming  is  being  put  down  from  600  to 


650  ft.,  where  the  eighth  level  will  be  run, 
being  75  ft.  below  the  greatest  depth  pre- 
viously worked  in  the  district.  Another  new 
vein  has  been  opened  up  at  the  Trethewey  in 
cross-cutting  on  the  150  ft.  level  from  shaft 
No.  2.  Though  not  wide  it  carries  high  silver 
contents.  The  Kerr  Lake,  in  consequence  of 
unsatisfactory  reports  as  to  the  ore  in  reserve, 
has  cut  out  its  extra  dividend,  reducing  the 
payment  for  the  last  quarter  of  the  year  to 
5%.  With  this  payment  the  company  will 
have  returned  to  the  shareholders  a  total  of 
$3,720,000,  being  124%  on  its  capitalization. 
Mercury  was  recently  discovered  in  the  ore  of 
the  Nipissing,  and  an  investigation  is  being 
undertaken  by  the  Bureau  of  Mines  with  the 
object  of  determining  in  what  mineral  com- 
binations this  metal  is  found,  and  whether  it 
occurs  in  sufficient  quantity  to  make  the  dis- 
covery of  commercial  importance. 

Later  information  confirms  the  report  as 
to  the  finding  of  a  rich  ore  deposit  on  the 
Brydges  claim,  otherwise  the  Little  Pet,  ad- 
joining the  Preston  property.  It  is  from  3  to 
4  ft.  wide  and  assays  high  and  appears  to  fol- 
low the  line  of  contact  between  the  porphyry 
and  greenstone  through  the  Preston.  A  min- 
ing plant  has  been  ordered  for  the  Brydges.  A 
controlling  interest  in  the  Porcupine  Imperial 
has  been  purchased  by  Charles  D.  Taylor,  of 
California.  At  the  Miller- Middleton  the  vein 
has  been  struck  by  cross-cutting  on  the  75-ft. 
level  and  shows  as  well  as  on  the  surface. 

At  Cobalt  the  Beaver  is  preparing  to  install 
a  mill  for  the  treatment  of  low-grade  ore  with 
a  capacity  of  50  tons  per  day.  It  will  be  con- 
structed on  the  Hardinge  principle  with  two 
crushers,  a  pebble-mill  and  a  tube-mill  taking 
the  place  of  stamps.  The  Drummond  is  de- 
veloping a  rich  though  narrow  vein  recently 
found  on  the  surface  that  has  been  followed 
underground  for  some  distance.  It  is  paralleled 
by  another  vein,  which  promises  well.  The 
annual  report  of  the  City  of  Cobalt  shows  a 
production  of  292,694  oz.  silver  from  392 
tons,  with  ore  in  reserve  estimated  to  contain 
181,650  oz.  It  was  decided  not  to  resume 
dividend  payments,  production  having  fallen 
off  owing  to  the  inability  of  the  company  to 
obtain  a  contract  with  a  concentrating  mill 
for  the  treatment  of  the  low-grade  ore. 

R.  B.  Stewart  has  prepared  a  preliminary 
report  for  the  Ontario  Bureau  of  Mines  on 
West  Shining  Tree,  the  new  gold  district  70 
miles  north  of  Sudbury.  The  region,  he  says, 
is  mainly  level,  with  few  rock  exposures.  The 
geology  is  complex.  The  discoveries  for  the 
most  part  are  located  on  zones  of  weathered 


NOVEMBER,    1911 


351 


schist  containing  veins  and  stringers  of  quartz 
generally  conforming  to  the  strike  and  dip  of 
the  schist.  As  to  their  extent  little  can  be 
said  as  not  much  stripping  has  been  done. 
The  quartz  widens  in  places  to  several  feet, 
but  does  not  carry  this  width  far  till  it  breaks 
up  into  stringers  or  disappears.  Mr.  Stewart 
visited  13  properties,  on  several  of  which  he 
found  free  gold.  At  Gosselins,  the  pioneer 
claim,  he  noted  that  the  stripping  had  dis- 
closed what  was  apparently  a  large  body  of 
quartz  carrying  free  gold.  Seven  samples 
collected  from  properties  where  no  gold  was 
visible  were  assayed  at  the  Provincial  assay- 
ofSce,  and  six  of  them  were  found  to  assay 
from  40c  to  $6  per  ton. 


it  is  anticipated  that  the  remaining  25  fathoms 
of  water  in  the  bottom  of  the  mine  will  be 
pumped  out  without  difficulty.  'I'he  upper 
levels  of  this  famous  old  copper  mine  prove 
to  have  been  '  skinned  '  by  tributers  in  the  pre- 
vious workmg,  but  the  management  hopes  for 
better  things  in  the  bottom  levels.  Such  an- 
ticipations usually  prove  fallacious,  and  it  is 
unreasonable  to  expect  that  the  old  people,  in 
the  days  of  extensive  tributing  and  scanty  de- 
velopment, left  much  payable  ground  standing. 
Companiesunwateringold  Cornish  miries  must 
be  prepared  with  sufficient  capital  not  only  to 
get  the  water  out,  but  to  prosecute  vigorous 
development.  Captain  Josiah  PauU,  of  South 
Crofty,  recently  made  an  inspectionof  themine. 


WHEAL    AOAR    PUMPING-ENGINE. 


CAMBORNE. 

Wheal  Hampton. — This  little  property, 
owned  by  the  St.  Stephens  Syndicate,  Ltd., 
and  situated  close  to  the  old  Tregurtha  Downs 
mineatMarazion,hasgot  intoits  regular  stride, 
now  that  the  reorganization  of  the  mill  has  been 
completed.  For  the  past  ten  weeks,  the  quan- 
tity of  black  tin  sold  at  the  tin  ticketings  has 
been  at  the  rate  of  five  tons  per  fortnight,  and 
there  is  every  reason  to  believe  that  this  pro- 
duction can  be  maintained.  Already  an  in- 
terim dividend  of  2s.  per  share  has  been  de- 
clared on  the  preference  shares. 

Tresavean. — Pumping  has  now  been  re- 
sumed at  this  mine  and  the  water  is  being  held 
below  the  260  fm.  level.  A  third  stationary 
pump  is  being  installed,  and  with  this  at  work. 


Basset  Mines. — The  last  two  or  three 
monthly  reports  from  this  property  have  been 
disappointing,  for  whereas  earlier  in  the  year, 
substantial  profits  were  being  made,  lately  the 
expenditure  has  nearly  equalled  the  receipts  ; 
indeed  for  the  last  four  weeks,  the  balance  in 
favour  of  the  mine  was  only  £14-,  excluding 
any  allowance  for  depreciation.  An  important 
feature  of  the  Basset  monthly  progress  reports 
is  that  an  estimate  of  the  receipts  and  expen- 
diture is  furnished,  and  this  useful  information 
is  no  doubt  much  appreciated  by  the  share- 
holders ;  Basset's  lead  in  this  direction  might 
well  be  followed  by  the  other  prominent  mines 
of  the  county.  With  this  evidence  of  progress, 
the  fact  that  the  manager  continues  the  absurd 
practice  of  reporting  discoveries  at  a  monetary 


352 


THE    MINING    MAGAZINE 


value  per  fathom  is  all  the  more  glaring.  The 
tonnage  stamped  for  the  past  month  was  3440, 
and  the  sales  of  black  tm,  41  tons,  or  a  recovery 
of  close  on  27  lb.  per  ton,  which  compares  with 
38'6  lb.,  the  average  produce  for  1910.^  Pas- 
coe's  shaft  is  being  sunk  in  a  large  lode  "  worth 
£lb  per  cubic  fathom  "  ;  this  is  a  little  above 
the  average  produce  of  the  mine. 

East  Pool  &  Agar.— A  loss  of  /^Se  as  com- 
pared with  a  profit  of  ;^90  for  the  previous 
quarter,  a  reduction  in  the  tonnage  milled  of 
over  300  tons  owing  to  shortage  of  water  for 
dressing  operations,  the  installation  of  a  tube- 
mill,  and  the  fact  that  the  whole  water  of  the 
two  mines  is  being  handled  by  the  Agar  90-in. 
Cornish  engine,  are  the  chief  features  of  the 
report  just  issued  for  the  quarter  ended  Sep- 
tember 23.  The  following  figures  are  interest- 
ing :— 

Ore  milled 13.418  tons 

Value  of  black  tin  sold  (107  tons) /12,000 

Value  of  arsenic  sold  /150 

Value  of  wolfram  sold ;^956 

Value  of  black  tin  per  ton  ore  milled...  19s.  6d. 

Produce  black  tin  per  ton  milled  17  9  lb. 

Total  receipts  per  ton  milled 19s.  lOd. 

Total  expenditure  per  ton  milled  19s.  lid. 

Loss  per  ton  milled Id. 

Development  footage  214  ft. 

Development  per  ton  milled  1  ft.  to  63  tons 

Employees  on  surface 250 

Employees  underground 233 

The  working  cost  given  above  is  close  on  2d. 
per  ton  more  than  shown  in  the  report,  but  the 
difference  is  accounted  for  by  a  contribution 
by  Mr.  Basset  oi  £\\1  towards  the  sinking  of 
East  Pool  engine  shaft,  which  has  been  wrongly 
deducted.  The  development  footage  is  still 
ridiculously  small  for  the  output ;  also  the 
number  of  employees  on  the  surface  is  high 
when  compared  with  the  underground  force. 
On  the  other  hand,  although  no  figure  is  fixed, 
large  sums  of  money  continue  to  be  spent  on 
the  renovation  of  Agar  shaft.  This  work  is  ab- 
solutely essential;  but  with  the  produce  so  low, 
with  no  reserve  of  funds  available,  and  with 
shareholders  unwilling  to  pay  calls,  the  expen- 
diture thereon  necessarily  curtails  develop- 
ment. 

Wheal  Peevor.  —  Recently  a  company 
with  an  authorized  capital  of  ;^30,000  was 
formed  to  acquire  and  work  this  group  of 
famous  mines  near  Redruth.  The  plant  now 
being  installed  has  been  removed  from  Wheal 
Gorland  at  St.  Day,  a  property  which  Edgar 
Allen  &  Co.,  who  are  largely  interested  in 
Peevor,  worked  for  wolfram,  but  which  they 
abandoned  some  months  ago.  The  scheme  is 
to  work  the  ground  above  adit  and,  if  results 
are  satisfactory,  to  unwater  the   mine  later. 


MELBOURNE. 
Labour  Situation.— The  veil  has  at  last 
been  lifted  in  respect  to  the  ambitions  of  the 
Labour  Party,  which  now  dominates  Federal 
politics.     In  Trades  Union  circles  "  Prefer- 
ence for  Unionists  "  has  long  been  the  cry. 
An  attempt  was  made  some  time  ago  by  the 
Labour  Party,  when  in  opposition,  to  induce 
the  Federal  Parliament  to  enact  that  this  prin- 
ciple should  be  recognized  in  the  statute  law 
of   the    Commonwealth,    but    the    legislature 
would  only  consent  to  preference  having  to  be 
given  to  unionists  "  other  things  being  equal."  . 
This  law  has  not  been  amended,  but  the  state- 
ment was  circulated  quite  recently  that  King 
O'Malley,   the    Minister    for    Home    Afifairs, 
had  issued  a  circular  which  stipulated  that  in 
public  works  preference  should  be  given  to 
unionists.     Further  enquiry  revealed  the  fact 
that  the  officers  of  the  Department  had  issued 
the  circular,  but  had  evidently  taken  their  cue 
from  the  tone  of  the  Minister,  who  assumes 
all  responsibility  in  connection  with  their  ac- 
tion.    The  Prime  Minister  was  questioned  and 
he  declined  to  bring  pressure  on  his  colleague, 
who  while  generally  regarded  as  a  wild  Yankee 
has  not  neglected  the  main  chance  during  his 
life  in  Australia.     To  this  end  he  has  adopted 
the  most  extreme  labour  views.     Mr.  Fisher's 
indirect  adhesion  to  Mr.  O'Malley's  circular 
at  once   led   the  leader  of    the    Opposition, 
Alfred  Deakin,  to  move  a  vote  of  censure  on 
the  Government  for  introducing  the  preference 
principle.     Mr.  Deakin  is  always  heard  at  his 
best  when  he  is  dealing  with  questions  of  this 
kind,  and  his  point  that  the  Government  could 
not  be  classed  as  a  private  employer  but  as 
representing  every  taxpayer,  whether  unionist 
or  non-unionist,  could  not  be  met.    He  insisted 
that  the  State  therefore  had  to  regard  each  of 
its  servants  in  the  broad  light  of  the  taxpayer, 
and  that  if  one  of  two  people  had  to  be  dis- 
charged preference  should  be  given  to  the  man 
of  greater  ability  without  regard  to  whether 
he  was  unionist  or  non-unionist.    No  real  reply 
was  attempted  by  the  labour  leaders  to  this 
argument,  because  it  was  irrefutable.     They 
put  up  the  American  axiom  that  to  the  victors 
belongs  the  spoil.  They  insisted  all  through  that 
their  policy  had  been  preference  to  unionists, 
that  they  would  be  forced  from  their  platform 
if  they  departed  from  their  election  pledges,  and 
that  they  intended  to  support  the  Government 
in  its  action. 

The  scheme  they  have  in  view,  of  course,  is 
to  force  electors  into  the  unionist  fold  and  so 
to  secure  for  themselves  a  majority  that  will 
enable  them   to  control  the  fortunes  of  the 


NOVEMBER,    1911 


353 


country.  Although  they  do  not  admit  it,  these 
are  the  tactics  of  Boss  Tweed  and  it  is  an 
ominous  beginning  for  the  Labour  Party  to 
have  openly  nailed  to  its  mast  the  banner  bear- 
ing the  words  "  spoils  to  the  victor."  Of  course 
unionists  are  delighted,  but  there  is  a  sober  ele- 
ment in  Australia  that  is  stirred  to  the  depths 
lest  there  be  a  possibility  of  corrupt  practices 
creeping  into  political  life  such  as  have  dis- 
figured the  course  of  American  legislation.  The 
best  thing  that  can  be  said  is  that  the  farming 
community  is  beginning  to  awaken  to  this  con- 
sideration. They  wanted  the  land-tax  to  break 
up  big  estates.  They  have  got  it,  and  they 
have  found,  as  so  many  other  communities 
have  done,  that  you  cannot  limit  the  effect  of 
taxation  to  any  one  class. 

Labour  Trouble  at  Mount  Lyell. — The 
restlessness  of  every  class  of  worker  ever  since 
the  Labour  Party  has  been  in  power  has  been 
intense,  and  the  latest  demonstration  has  oc- 
curred at  Mount  Lyell,  where  the  men  threw 
down  their  tools  because  the  general  manager, 
Robert  Sticht,  found  it  necessary  to  discharge 
a  worker  named  White  who  had  entered  the 
mine,  without  permission,  in  his  off-time  to  find 
out  whether  two  contractors  were  disobeying 
the  Union  rule  that  all  members  of  the  Union 
should  work  exactly  8  hours.  The  entrance 
to  the  mine  at  such  a  time  was  unpardonable, 
unless  the  control  of  the  whole  of  the  property 
was  to  be  handed  over  to  the  unionists.  When 
the  man  had  been  discharged ,  the  Union  claimed 
that  he  should  be  reinstated,  as  they  said  the 
punishment  w^as  greater  than  the  offence  justi- 
fied. They  claimed  that  the  management,  by 
permitting  contractors  to  work  their  own  time, 
and  throwing  upon  the  Union  the  respon- 
sibility of  disciplining  them  to  the  eight-hour 
system,  wasunderminingthat  system, although 
the  company  has  recognized  the  principle  for 
years  past.  Upon  the  management  declining 
to  yield,  the  Union  gave  notice  that,  if  before  a 
certain  hour  it  did  not  reinstate  White,  the  men 
would  be  withdrawn.  This  was  done,  and  at  the 
same  time  the  step  was  taken  tonotif  y  the  direc- 
tors that  a  50%  increase  in  wages  was  asked  for, 
that  smoking  while  on  shift  was  wanted,  that  the 
fumes  from  the  explosives  used  were  objected 
to,  and  that  the  right  was  claimed  that  Union 
officials  should  be  recognized  as  such  on  the 
mines.  All  sorts  of  high  officials  have  sought 
to  arbitrate  between  the  workmen  and  the  com- 
pany, but  the  Board  throughout  declined  to  per- 
mit the  question  of  the  reinstating  of  White  to 
be  discussed.  They  said  they  would  give  con- 
sideration to  the  question  of  the  increase  in 
wages  and  the  other  demands  of  the  men,  pro- 


vided proper  time  be  given  for  such  considera- 
tion. On  the  day  of  writing  the  two  sides  were 
absolutely  at  issue. 

Mr.  Sticht  declares  that  he  would  sooner 
resign  his  position  than  consent  to  White  being 
reinstated,  and  the  Board  to  a  man  support 
him.  If  theengine-driversshould  throw  in  their 
lot  with  the  strikers  then  there  will  be  a  risk 
of  the  mines  being  flooded  and  the  whole  of  the 
superphosphate  business  of  the  company  being 


brought  to  a  standstill.  Tliis  would  be  a  very 
serious  matter  just  now,  because  this  is  the 
time  of  the  year  when  the  company  is  busily  en- 
gaged in  the  manufacture  of  artificial  manures. 
Great  Fitzroy. — The  management  of  this 
mine,  in  Queensland,  has  been  devoting  a  good 
deal  of  time  to  the  readjustment  of  the  mill. 
The  plant  is  now  running  about  half-time,  and 
securing  an  extraction  of  714%  copper  and 


354 


THE    MINING    MAGAZINE 


57i%  of  the  gold  in  the  ore.      Extraction  has 
been  affected  by  an  accident  m  the  grinding 
section,  prior  to  which  a  test  run  gave  a  re- 
covery of  81%  copper  and  65%  gold.     If  such 
an  extraction  could  be  maintained,  the  com- 
pany would  be  able  to  show  some  little  profit, 
without  any  improvement  in  the  price  of  cop- 
per.    Smelting  is  not  altogether  satisfactory,  ■ 
as  the  ore  is  exceedingly  silicious,  hence,  with 
the  fall  in  the  grade  of  ore,  the  smelter  work 
shows  a  loss  of  ^1200  for  September.     Better 
returns  are  expected  for  October,  and  in  No- 
vember the  hope  is  that  a  profit  will  be  earned. 
Mount  Elliot. — Another  Queensland  com- 
pany that  has  resumed  smelting  is  the  Mount 
Elliott  where  operations  were  interrupted  by 
a  creep  in  the  mine.    The  plant  has  been  shut- 
down since  June  and  the  furnace  was  put  into 
commission  again  in  September.      Meanwhile 
the  underground  workings  have  been  made  se- 
cure and  the  usual  output  of  ore  can  now  be 
maintained.  The  company  has  taken  an  option 
on  the  Limestone  claim  near  Cloncurry,  which 
is  one  of  the  most  promising  properties  in  the 
district.    The  price  at  which  the  claim  is  under 
offer  is  trifling  and  the  expectation  today  is 
that  the  company  has  obtained  a  bargain.    Of 
course,  this  can  only   be  proved  by  further 
exploration.     The  Mount  Elliott  company  is 
handling  the  Hampden  company's  matte  under 
advantageous  terms  to  both  parties.     At  the 
latter  mine  the  No.  2  plant  is  being  pushed 
ahead  as  fast  as  is  possible,  while  no  time  is 
being  lost  by  the  Government  in  laying  the 
railway  line  that  will  connect   the   Duchess 
mine  with  the  Hampden.     Developments  un- 
derground at  the  former  mine  show  the  pre- 
sence of  high-grade  ore,  and  the  company's 
new  Trekelana  lease  is  opening-up  well.    The 
great  question  throughout  the  district  is  whether 
a  central  smelting  establishment  shall  be  pro- 
vided.    Therefore  it  has  been  suggested  that 
the  Hampden  and  Mount  Elliott  companies 
should  fuse,  but  a  difficulty  now  in  the  way 
seems  to  be  the  apportionment  of  interests. 
The  first  section  of  the  survey  for  a  railway 
that  will  practically  link  Cloncurry  with  the 
big  mineral  district  to  the  northwest,  and  then 
reach  the  Gulf  of  Carpentaria  at  a  point  where 
a  deep  harbour  could  be  built,  is  now  com- 
pleted.    Such  a  railway  would  be  of  immense 
importance  to  the  vast  mineral  field  that  lies 
around  Cloncurry. 

New  Zealand  Coal. — The  balance-sheet 
of  the  State  coal  mine  of  New  Zealand  is  not 
an  impressive  document.  The  results  for  the 
year  indicate  that  a  profit  of  ;^  1051  was  made, 
.against  ^4909  for  the  preceding  year.     Seeing 


that  207,000  tons  of  coal  was  sold  and  that  the 
Railway  Department  was  charged  a  higher 
price  than  the  private  consumer,  such  a  re- 
turn does  not  satisfy  anyone.  The  largest  con- 
sumers were  private  buyers  and  the  shipping 
companies,  who  took  88,500  tons,  as  against 
62,900  tons  sent  to  the  various  depots  to  be 
retailed  to  the  public.  The  output  of  the  mine 
was  just  about  the  same  as  during  the  pre- 
ceding twelve  months,  but  the  working  ex- 
penses were  heavier,  and  in  addition  a  large 
quantity  of  slack  was  produced.  The  Point 
Elizabeth  mine  was  responsible  for  an  output 
of  209,253  tons  and  the  Seddonville  mine  for 
51,550  tons.  The  gross  output  of  the  Point 
Elizabeth  mine  to  date  is  1,322,000  tons. 
There  is  a  debenture  debt  of  ^130,000  to  be 
wiped  out  in  connection  with  the  two  enter- 
prises, and  a  good  deal  more  profit  will  have 
to  be  made  if  that  liability  is  to  be  rapidly 
reduced. 

Tasmania  Gold. — The  news  that  the  Tas- 
mania gold  mine  has  had  to  levy  a  call  after 
fighting  against  odds  for  so  many  years  has 
occasioned  great  regret  in  mining  circles.  The 
fact  of  the  matter  is  that  the  shoot  of  gold  has 
not  maintained  its  richness  nor  its  size.  The 
water  trouble  also  is  always  serious  and  en- 
tails high  costs.  The  reconstruction  of  the 
company  was  carried  through  easily  because 
a  shoot  of  good-grade  ore  was  met.  Develop- 
ments since  then  have  not  been  so  encourag- 
ing, and  with  costs  heavy  the  only  chance 
ahead  was  to  improve  the  finance  by  making 
calls. 

Broken  Hill. — This  district  is  in  a  pros- 
perous condition.  The  high  prices  of  both 
lead  and  spelter  have  helped  both  the  mining 
and  the  process  companies.  Of  the  latter  the 
most  prosperous  is  the  Amalgamated  Zinc, 
and  the  news  is  just  out  that  a  shilling  divi- 
dend for  the  quarter  has  been  declared.  The 
hope  of  the  shareholders  was  that  as  the  com- 
pany has  ;^70,000  or  ^80,000  cash  in  hand,  a 
higher  dividend  would  have  been  forthcoming, 
but  the  policy  of  the  directors  is  to  build  up 
the  reserve  to  ;^1 50,000.  They  would  then 
be  able  to  face  any  fluctuations  in  the  metal 
market  with  equanimity  and  keep  dividends 
at  one  level  unless  a  real  slump  should  take 
place.  In  all  probability  a  larger  dividend 
will  be  available  for  the  December  term.  The 
Broken  Hill  Proprietary  company,  aided  by 
the  price  of  zinc,  has  within  the  past  three 
months  replaced  ;^75,000  to  reserve.  Its 
cash  reserve  now  stands  at  over  ;^95,000.  Of 
the  old  reserve  fund  of  ;^260,000,  no  less  than 
^239,800   has  been  used  in   the  company's 


NOVEMBER,    1911 


355 


business,  principally  in  connection  with  its 
custom  works.  There  had  in  addition  been 
an  expenditure  of  ;^86,000  on  the  spelter 
plant,  which  had  been  paid  for  out  of  the 
reserve  fund.  By  replacing  ^75,000  to  re- 
serve that  fund  has  almost  recouped  its  out- 
lay on  the  plant,  with  the  result  that  it  now 
stands  at  pretty  well  its  original  figure  of 
^260,000,  leaving  the  spelter  plant  really 
showing  in  the  books  at  only  about  / 11,000. 
The  company  may  not  bring  out  the  figures 
in  this  way,  but  that  is  the  position.  The 
other  interesting  feature  in  connection  with 
Broken  Hill  mining  is  the  developments  at 
the  British  mine.     Here  boring  from  the  No. 


NEW  YORK. 
Steel  Corporation  affairs  occupy  the 
centre  of  the  stage  just  now.  The  suit  aim- 
ing at  its  dissolution,  filed  by  the  Government 
on  October  26,  was  not  wholly  unexpected, 
but  it  was  commonly  supposed  that  action 
would  be  postponed  until  the  courts  had  had 
an  opportunity  to  dispose  of  certain  other  suits 
of  similar  nature  now  pending.  The  suit  was 
filed,  furthermore,  only  a  few  hours  after  the 
directors  of  the  corporation  had  formally  de- 
cided to  relinquish  certain  leases  that  it  held 
on  iron-ore  lands  in  Minnesota,  and  to  reduce 
the  freight-charges  on  its  railroad  in  that  dis- 
trict, both  of  which  acts  had  been  expected  to 


MOREXCI,    ARIZOy.A,     SHO^VIXO    ARIZOS'A    COPPED    CO.'S    COSC EXTRATUli    ASD    SMKLTEIl. 


3  level  of  Thompson's  shaft  proved  the  up- 
ward continuation  of  the  shoot  of  ore  that  had 
been  drilled  at  No.  5,  6,  and  7  levels,  and  is 
also  being  opened-up  by  a  big  cross-cut  for 
110  ft.  in  length  at  the  No.  9  level  with  the 
face  in  the  latter  workings  still  in  high-grade 
sulphides.  The  diamond-drill  is  now  at  work 
on  the  No.  2  level.  In  addition,  the  company 
has  opened  a  cross-cut  off  No.  1  level  which 
has  run  into  carbonate  ore.  The  market  here 
has  responded  to  these  developments  and  the 
shares  of  the  company  are  being  more  freely 
bought  than  all  the  rest  of  the  Barrier  mines 
put  together.  There  are  rumours  that  an 
attempt  is  to  be  made  to  reconstruct  the  com- 
pany in  London  under 'distinguished 'auspices. 
Any  project  of  this  kind  will  receive  the 
opposition  of  the  shareholders  at  Adelaide. 


delay  prosecution,  inasmuch  as  both  the  leases 
and  the  exorbitant  freight-rates  had  been  the 
subject  of  adverse  criticism.  In  now  familiar 
terms,  the  Government  accuses  18  individuals, 
among  whom  are  Morgan,  Rockefeller,  Car- 
negie, Gary,  Prick,  and  Gayley,  17  corpora- 
tions engaged  in  the  manufacture  of  iron  and 
steel  products,  and  a  long  list  of  iron-mining 
companies,  of  unlawful  acts  tending  toward 
combinations  and  conspiracies  in  restraint  of 
trade  and  commerce,  and  brought  about  by 
illegal  arrangements  to  monopolize  trade  and 
fix  prices,  and  to  destroy  competition.  In 
conclusion,  the  Government  appeals  to  the 
Court  to  enjoin  any  further  continuance  of 
the  present  plan  by  which  the  subsidiary  con- 
cerns pay  their  dividends  into  the  general 
funds  of  the  Steel  Corporation  ;  in  short,  to 


356 


THE    MINING    MAGAZINE 


dissolve  the  Trust  into  its  component  elements. 

The  complaint  goes  deeply  into  the  history 
of  the  Trust,  tracing  its  growth  from  the  or- 
ganization of  the  Federal  Steel  Co.,  in  1898, 
up  to  the  absorption  of  the  Tennessee  Coal  & 
Iron  Co.,  in  1907.  In  describing  each  event 
the  complaint  take  occasion  to  point  out  to 
what  extent  the  capitalization  was  expanded, 
and  how  much  of  the  new  capital  stock  was 
pocketed  by  the  promoters  of  the  consolidation. 
It  is  estimated  that  not  less  than  $130,000,000 
(par  value)  was  sequestrated  at  one  time  or 
another  by  the  underwriting  syndicates.  Again, 
in  referring  to  the  absorption  of  the  Car- 
negie Steel  Co.,  the  complaint  states  that 
$492,006,000  was  paid  for  that  property,  for 
which  Mr.  Morgan  had,  not  long  before,  re- 
fused to  pay  $160,000,000.  Finally,  in  con- 
nection with  the  absorption  of  the  Tennessee 
Coal  &  Iron  Co.,  the  complaint  alleges  that 
Messrs.  Frick  and  Gary  brought  improper  in- 
fluence to  bear  on  President  Roosevelt,  in  fact, 
were  guilty  of  misrepresentation  when  appeal- 
ing to  him  for  permission  to  commit  what  was 
plainly  a  breach  of  the  law. 

The  reply,  unofficially  tendered  as  yet,  is  a 
general  denial  of  any  actual  or  intended  wrong- 
doing, asserting  that  the  corporation  had  never 
sought  nor  exercised  any  monopoly  of  trade, 
nor  any  improper  influence  in  the  regulation 
of  prices.  In  this  connection,  a  bit  of  inside 
history,  which  I  have  learned  from  one  well 
qualified  to  know  the  facts,  is  of  interest. 
When  E.  C.  Converse,  in  whose  mind  origin- 
ated the  idea  of  the  steel  trust,  brought  to 
Mr.  Morgan  a  list  of  the  concerns  that  were 
contemplated  for  consolidation,  together  with 
estimates  of  their  value,  Mr.  Morgan  blue- 
pencilled  the  list  rather  remorselessly,  declar- 
ing that  he  would  have  nothing  to  do  with 
any  combination  approaching  a  monopoly  of 
the  steel  business,  or  in  other  ways  coming 
under  the  ban  of  the  Sherman  law.  Some 
concerns  that  sought  to  be  absorbed  were 
refused  admission.  As  a  result  of  this  stand, 
the  Trust  does  not  now  control  much  more 
than  one-half  the  total  steel  output  of  the 
country,  and,  in  fact,  the  proportion  is  smaller 
now  than  at  the  outset ;  on  this  phase  of  the 
complaint  the  Trust  seems  to  have  a  clear 
case.  On  the  score  of  fixing  prices,  also,  and 
of  controlling  output,  the  Trust  can  likewise 
present  a  fairly  convincing  rejoinder.  To  sus- 
tain this  accusation,  the  Government's  com- 
plaint refers  to  the  nominally  purely  social 
gatherings  at  the  invitation  of  President  Gary, 
alleging  that  prices  were  there  regulated  and 
output  allotted.     This  will  be  hard  to  prove. 


The  weak  points  in  the  Steel  Corporation's 
defence,  it  seems  to  me,  are  the  obvious  facts, 
first  that  at  each  absorption  of  another  con- 
cern, the  amount  of  stock  issued  in  payment 
for  it  was  grossly  in  excess  of  its  real  value, 
even  allowing  for  full  capitalization  of  its 
earning  capacity,  and  second,  that  the  con- 
ditions leading  to  the  merger  of  the  Tennessee 
Coal  &  Iron  Co.  were  a  transparent  fake.  In 
connection  with  the  first  point,  it  was  well 
known  at  the  time  it  was  issued  that  the  com- 
mon stock  of  the  United  States  Steel  Cor- 
poration represented  nothing  but  anticipated 
earnings  and  good-will,  which  were  optimisti- 
cally capitalized  at  $500,000,000.  By  setting 
apart  liberal  allowances  for  construction,  re- 
pairs, sinking-fund,  and  surplus,  however,  the 
corporation  has  added  about  $335,000,000  to 
its  assets,  by  virtue  of  which  the  common 
stock,  once  practically  given  away,  now  has 
a  value  approximating,  if  it  does  not  actually 
exceed,  its  market  quotation.  While  thisdoubt- 
less  worked  a  hardship  on  those  whose  pur- 
chases have  helped  to  make  the  assets  tan- 
gible, it  may  prove  not  to  have  been  illegal. 
As  to  the  Tennessee  merger,  whether  Frick 
and  Gary  had  only  the  highest  altruistic  mo- 
tives in  seeking  to  allay  the  stock  -  market 
panic  of  1907  by  taking  over  the  control  of 
that  valuable  and  active  competitor,  or  whether 
they  did  or  did  not  mislead  President  Roose- 
velt, the  deed  seems  to  have  been  a  flagrant 
violation  of  the  law,  and  furthermore  the  Con- 
stitution gives  no  discretion  to  the  President 
to  ignore,  much  less  sanction,  a  proposal  to 
violate  the  law. 

The  outcome  of  the  suit,  in  the  opinion  of 
those  well  qualified  to  know,  will  probably  be 
the  evolution  of  some  arrangement  whereby 
further  illegal  consolidations  will  be  rendered 
impossible,  without  proceeding  to  the  extre- 
mity of  demanding  absolute  disintegration. 
The  directors  of  the  Corporation  are  too 
powerful  and  they  have  too  much  at  stake 
to  submit  tamely  to  the  demands  of  the  At- 
torney-General. The  suit  will  be  strenuously 
contested,  but  the  Government  has  announced 
its  intention  to  hasten  procedure  as  much  as 
possible  in  order  to  disarm  criticism  that  the 
suit  was  brought  just  at  this  time  for  political 
efi'ect  on  the  forthcoming  presidential  elec- 
tion. 

1'h  e  magnitude  of  the  Steel  Corporation  al- 
most passes  comprehension.  Its  bonded  and 
share  capitalization  totals  $1,465,000,000,  of 
which  the  stock,  amounting  to  $868,580,000, 
is  divided  among  1 50,000  or  more  shareholders, 
by  far  the  largest  list  on  the  books  of  any 


NOVEMBER,    1911 


357 


American  concern.  Its  annual  gross  receipts 
exceed  by  several  million  dollars  the  total  in- 
come of  the  United  States  Government  from 
all  sources.  In  the  first  nine  years  of  its  ex- 
istence its  total  net  earnings,  averaging  25% 
of  its  gross  income,  have  reached  the  enor- 
mous aggregate  of  J  250  million  dollars, 
out  of  which  it  has  distributed  dividends  of 
1394,000,000,  paid  a  bond  interest  of 
$208,790,000,  besides  putting  $210,000,000 
of  earnings  back  into  improvements  and  en- 
largements, and  accumulating  a  net  surplus, 
at  the  end  of  1910,  amounting  to  $164,000,000. 
In  point  of  output,  the  Corporation  produces 
annually  more  steel  than  all  Germany,  more 
than  twice  as  much  as  Great  Britain,  and 
three  times  as  much  as  France. 

The  Stock  Market  was  but  slightly  af- 
fected by  the  announcement  of  the  Steel  Trust 
suit.  Steel  common  dropped  quickly  from  55 
to  50,  the  lowest  it  has  been  since  1909,  while 
the  preferred  declined  from  105  to  103,  also 
the  lowest  it  has  been  for  a  long  time.  On  the 
day  after  the  announcement,  over  700,000 
shares  of  the  common  stock  changed  hands 
on  the  Stock  Exchange,  amounting  to  nearly 
one-half  the  day's  transactions  in  all  securi- 
ties on  that  floor.  Mining  stock,  however, 
showed  not  the  least  sympathy  with  Steel  ; 
in  the  day's  excitement,  of  course,  they  sold 
off  fractionally,  but  quickly  recovered  and 
then  resumed  their  slow  upward  course.  As 
compared  with  a  month  ago.  Amalgamated 
has  risen  5  points  ;  A.  S.  &  R.  common,  3  ; 
Chino,  31  ;  Tennessee  Copper,  3i  ;  and  Utah 
Copper,  4i  points. 

The  Tariff,  which  without  exaggeration 
can  be  named  the  mother  of  trusts,  still 
rankles  in  the  minds  of  the  public,  in  spite 
of  the  President's  tour  of  explanation  and 
apology.  No  high  order  of  intelligence  is 
needed  to  perceive  the  connection  between  a 
Government  bounty  of  $8  per  ton  on  steel 
rails,  for  example,  and  the  enormous  profits 
of  the  Steel  Trust.  The  Tariff  Commission, 
to  which  the  President  pins  his  whole  faith, 
promises  to  be  ready  with  its  report  on  wool 
by  the  time  the  next  Congress  meets,  in 
December,  and  other  schedules  will  then 
come  in  for  examination.  It  is  safe  to  say 
that  the  next  time  tariff  revision  occurs,  it 
will  be  m  a  genuinely  downward  direction. 

The  Copper  market  continues  to  im- 
prove. Domestic  stocks  have  been  reduced 
by  reason  of  decreased  output  during  the  past 
month,  and  by  encouragingly  large  sales  both 
for  home  consumption  and  for  export.  Ship- 
ments to   Germany  continue   heavy.       It    is 


hard  to  find  any  sound  reason  to  expect  a 
lower  price  for  copper  in  the  near  future,  in 
spite  of  the  additions  to  producing  capacity 
that  are  occurring  almost  daily.  Braden  and 
Chino  have  recently  entered  the  producers' 
list,  and  both  should  be  working  at  nearly 
full  capacity  within  a  few  months.  The  mar- 
ket is  in  such  condition  now  that  mere  price 
has  but  little  influence  on  consumption  ;  in 
fact,  the  lower  the  price  goes  the  more  reluct- 
ance the  consumers  display  in  placing  their  or- 
ders in  advance,  wherefore  the  hand-to-mouth 
policy  is  now  firmly  established.  The  market 
has  reduced  itself  to  a  question  for  the  produc- 
ers to  settle  by  themselves,  on  the  basis  of  cost. 


The  Copper  Range  Wharf,  Michigan. 

Enthusiastic  welcome  awaits  the  newly 
formed  Anglo-French  Financial  Company  of 
Canada,  which  Frederick  W.  Baker  and  Nor- 
ton Griffiths  have  organized  for  investment  in 
American  mines  and  railways.  That  men  as- 
sociated with  the  Venture  Corporation  are  dis- 
posed to  increase  their  holdings  in  this  country 
and  Canada  is  taken  as  indicating  that  their  ex- 
perience here  has  been  satisfactory.  [Neither 
of  these  gentlemen  is  now  associated  Avith  the 
London  Venture  Corporation,  the  successor 
of  the  Venture  Corporation ;  Mr.  Baker  is  with 
the  Hirsch  Syndicate.— Editor].  Whether 
they  will  find  a  new  Camp  Bird  at  Porcupine 
is  uncertain,  but  at  least  the  advent  of  another 
experienced  and  wealthy  group  of  investors 
will  be  welcome.  In  Canada  there  has  been 
some  criticism  of  Bewick,  Moreing  &  Co.  in 
connection  with  the  Hollinger.  The  truth 
seems  to  be  that  when  it  was  announced  that 
their  firm  had  gone  into  Hollinger,  speculators 
put  the  shares  up  to  such  a  figure  that  Bewick, 
Moreing  &  Co.  were  able  to  sell  out  and  make 
a  profit  of  about  the  amount  needed  for  ex- 
ploration of  their  other  properties.  '  Taking 
profits'  naturally  appears  wrong  to  the  people 
from  whom  they  are  taken.  [More  money  is 
made  by  selling  than  by  buying  mines,  be- 
cause most  mines,  especially  the  rich  ones,  are 
sooner  or  later  over-valued  by  the  speculative 
public— Editor]. 


358 


THE    MINING    MAGAZINE 


STATISTICS 

Stocks  of  Copper  in  England  and  the  Continent. 


Reported  by  Henry  R.  Merton  &  Co. 

Aug.  31. 
Tons 

Sept.  30 
Tons 

Oct.  31 
Tons 

52,661 

5,728 
1,975 
6,550 

52.111 

5.654 
2,375 
7,200 

48,357 

5,704 

2,075 

Afloat  from  Australia 

5,900 

Total 

66,914 

7.650 

10.800 

67,340 

7,250 

11,100 

61.836 

In  RoffprHam 

6.900 

In  Hamburg  (estimated)... 

10.200 

A.MERicAN  Copper  Producers'  Association. 
In  Tons  of  2.240  lb. 


Deliveries 


Produc- 
tion.    Domes- 


Foreign    Total 


January  1911 51.650 

February    49,030 

March 58.273 

April 52.716 

May 56.679 

June 55.605 

July  50.075 

August 56,024 

September 51,602 

October  52.792 


18,785 
22,553 
29,500 
23.396 
28.814 
27.525 
25,438 
26,757 
25,587 
28.602 


23.753 
20,139 
26.375 
27.736 
27,669 
31,902 
33,429 
31,185 
22,689 
26,832 


42,538 
42.692 
55,875 
51,132 
56,483 
59,427 
58,867 
57,942 
48,276 
55,425 


Stocks  at 
end  of 
month 


63,591 
69.929 
72,325 
73,909 
74,105 
70,283 
61,491 
59.573 
62,899 
60,267 


Production  of  Gold  in  the  Transvaal. 


Rand 


Totals,  1910. 

January  1911 

February  

March 

April  

May 


June    

July 

August  

September 
October 


Oz. 

7,228,588 

625,862 
585,683 
649,247 
638,421 
658,196 
657,023 
679,881 
682,405 
669,773 
677.923  I 


Else- 
where 

Oz. 

305,532 

25,201 
24,965 
26,818 
29,293 
27,755 
27,544 
29,377 
31,002 
30,852 
30.721 


Total 


Value 


Oz. 
7,534.120 

651,027 
610,828 
676,065 
667,714 
685,951 
684,567 
709,258 
713,407 
700,625 
708.644 


Cost  and  Profit  on  the  Rand. 

Month. 

Tons 

Yield       Costs 
per  ton    per  ton 

Profit 
per  ton 

Total 
profit 

January  1911... 

1.865,232 
1,712,198 
1,960.678 
1,926.583 
2.002,926 
1,986,559 
2,095,220 
2,107,809 
2,037,329 

s.    d.       s.    d. 
26    6   ,    17  11 
28    0        18     3 

s.    d. 

10    1 
10    3 
9    9 
10    1 
9    7 
9    8 
9    4 

8  11 

9  4 

£ 

930.059 
874,612 

March  

28    6 
27    7 
27    7 
27    6 
27     2 

26  8 

27  4 

17  11 
l7    6 
17  10 
17  11 
17  10 

17  9 

18  1 

949,415 

971,858 

May 

956.823 

June  

960,381 

Tulv 

969  687 

August 

September 

967,457 
952,665 

Totalsand  aver- 
ages for  1909.. 
Ditto  1910 

20.543.759 
21.432.541 

28  11 
28    6 

17     1 
17     7 

11     6 
10    6 

11,794,376 
11.216.105 

Natives  Employed  in  the  Tran.svaal  Mines. 


January  31 

February  28.... 

March  31  

April  30 

May  31  

June  30 

July  31 

August  31 

September  30 
October  31    ... 


Gold 
mines 


183.268 
189,434 
193,457 
194,328 
190,392 
186,940 
181.582 
179,810 
179,619 
179.194 


Coal 
mines 


;,357 

;,5i3 

!,493 
1,511 
!,379 
1,212 
1,122 
i,182 
t,045 
!,078 


Diamond 
mines 


Total 


9,991 
9.814 
10,061 
10,272 
10,425 
10,597 
11,054 
11,292 
11,475 
11.319 


201.616 
207,761 
212,011 
213,111 
209,196 
205.749 
200.758 
199.284 
199,139 
198,591 


Gold  Output  of  India. 

Year  1909 

Year  1910      1       Oct.   1911 

1911  to  date 

£2,083,901 

£2,104.858 

£181,858 

£1,595.651 

Production  of  Gold  in  Rhodesia. 


Month. 


1908 


1909 


£ 

32,002,912 

2,765,386 
2,594,634 
2,871.740 
2.836,267 
2,913.734 
2.913,734 
3.012.738 
3.030,360 
2,976,065 
I    3.010.130 


January 

February  ... 

March  

April  

May 

June  

July 

August  

September 

October 

November-- 
December-- 

Totals 


£ 

199.388 
191,635 
200,615 
212,935 
223,867 
224,920 
228,151 
230,792 
204,262 
205,466 
196.668 
217.316 


£ 
204.666 
192,497 
202,157 
222,700 
225,032 
217,600 
225,234 
228.296 
213.249 
222.653 
236.307 
233,397 


2,526,007    2.623.788 


1910 


1911 


£ 

227.511 
203,888 
228,385 
228,213 
224,888 
214,709 
195.233 
191.423 
178.950 
234,928 
240.573 
199.500 


2,568.201 


£ 

207.903 
203.055 
231.947 
221,296 
211,413 
215,347 
237,517 
243,712 
225,777 


Production  of  Gold  in  West  Africa. 


Month. 

1909 

1910 

1911 

Oz. 

Value 

Oz.       Value 

Oz.         Value 

January  

February    -- 

22.817 
21,403 
23,186 
21,491 
25,104 
17,340 
17  331 

£ 

91,112 
86,210 
93,556 
88.071 
100.056 
70,561 
70,523 
71,614 
72.963 
65,813 
73,824 
71,332 

17,357 
16,976 
17,627 
16,363 
16,590 
17,194 

£ 
70,699 
68,469 
71,954 
67,069 
68,355 
70.988 

15.903 
15.179 
16.387 
17.237 
24,427 
22,555 
22,510 
25,385 
26.717 

£ 

66.107 
63,081 
67,673 

70,880 

May 

96.409 
92,174 

tulv  

15,564  !    58.551 

91,955 

August  

September--. 

October  

November  -.. 
December  .-- 

17,766 
18,125 
15,957 
17,882 
17,570 

13,921 
11,497 
13,341 
14,021 
15,042 

57,713 
47,746 
55,046 
57,658 
61.737 

103,753 
109,039 

235,972 

955,635  ll85,493 

755.985 

— 

— 

Production  of  Gold  in  Western  Australia. 


Month. 

Export 
oz. 

Mint 
oz. 

Total 
oz. 

Total 
value 

Total,  1910  

363,496 

1.209,856 

1.573,352 

£ 

6,682,042 

January  1911  

17,463 

22,047 
12,296 
20,455 
22,076 
10,523 
15,334 
11,521 
5,011 
10.664 

102,035 

84.991 

93.267 

91.791 

88.952 

106.464 

97.387 

102.477 

114.615 

106.733 

119,498 
107.038 
105.563 
112,246 
111.028 
116.987 
112.721 
113.993 
119.626 
117,397 

507,592 

454,666 

March         

448,426 

476,787 

Mav             

471,615 

497,188 

]n]v                       

478,805 

484,168 

508,135 

October      

498.668 

Other  Australasian  Gold  Production 

1909 

1910      1    October 
1910      1         1911 

1911 
to  date 

Queensland  

£ 

1.916.468 

869.546 

2.006,910 

2,897,340 

£ 

1,840,337 

803,727 

1,896,322 

2,422,700 

£ 

146.975* 
93.935 
152.964 
179.985 

£ 

1.208.160* 

New  South  Wales 

New  Zealand 

Victoria 

648,369 
1.535.615 
1,770.107 

*  September  figures  only. 


Sale  of  Tin  Concentrate  at  Redruth  Ticketings- 


September  4.  1911 
September  18,    .. 
October   2. 
October  16. 
October  30, 


Tons 


Value 


220 

2493 

224| 

251 

235^ 


£25.262 
£27,170 
£25.221 
£28.342 
£27.176 


Average 


£ll4  16 
£l08  15 
£ll2  4 
£ll2  19 
£115     8 


Exports  of  Tin  and  Ore  from  Straits  and  Bolivia. 
Reported  by  A.  Strauss  &  Co. 


Metal  from  Straits  to  Europe 
and  America         

Sept.  1911 
tons 

5148 

2034 

Oct.  1911 
tons 

4.385 

1,947 

1911  to  date 
tons 

■     44.325 

Metallic  Content  from  Bolivia 
to  EuroDe            

19,294 

NOVEMBER,    1911 


359 


METAL  MARKETS 

COPPER. 

Average  prices  of  cash  standard  copper: 

Oct.  1911.  Sept.  1911.         Oct.  1910. 

£55.  5s.  3d.  ^55.  7s.  Id.  £56.  16s.  2d. 
September  opened  with  all  the  producing 
agencies  again  in  competition,  the  Amalga- 
mated interests  having  reduced  their  price 
from  £5^.  5s.,  for  which  they  had  so  long 
held,  to  £51 .  In  Europe  buyers,  held  back- 
by  political  uncertainties,  were  unresponsive, 
but  American  consumers,  who  had  long  ab- 
stained from  purchasing,  relieved  producers 
of  some  accumulated  stocks.  Subsequently 
the  publication  of  the  American  figures  was 
followed  by  depression  on  the  metal  exchange 
and  a  decline  of  10s.  in  standard  sorts.  The 
increase  in  stocks  combined  with  the  heavy 
decline  in  exports  formed  the  basis  of  com- 
ment. The  decreased  output  appears  to  be 
due  to  the  closing  of  some  smaller  producers, 
the  first  indication  of  involuntary  curtailment 
brought  about  by  the  continuance  of  low 
prices.  Producers  again  made  slight  conces- 
sions and  then  was  seen  the  effect  of  the  small 
September  shipments  and  the  depletion  of  con- 
sumers' stocks.  Helped  by  good  European 
statistics  and  more  cheery  reports  from  stock 
exchange  circles,  the  pent-up  buying  power 
rapidly  developed  into  a  formidable  movement 
which  forced  American  prices  up  again  to  12i 
c.  and  large  orders  were  placed  in  the  United 
States  and  Europe  for  October,  November, 
and  December.  Standard  copper  rose  20s., 
but  the  price  has  since  given  way  before  the 
announcement  of  the  prosecution  of  the  Steel 
Corporation.  The  decline  cannot  last,  as  the 
enormous  consumption  requires  a  constant  re- 
plenishing of  stocks,  and  if  the  American  situ- 
ation makes  further  progress,  a  rapid  rise  in 
prices  is  probable.  Italy  is  buying  largely  for 
sulphate. 

TIN. 

Average  prices  of  cash  Straits  tin  : 
Oct.  1911.  Sept.  1911.  Oct.  1910. 

£\^7.  2s.  9d.    ^180.  16s.  lid.    ;^164.  4s.  9d. 

By  aggressive  manipulation  the  bull  party 
early  in  the  month  raised  prices  from  ;^1 76.  10s. 
to  ^183.  15s.,  at  the  same  time  lending  Octo- 
ber tin  to  January  and  thereby  transforming 
a  backwardation  of  £2.  10s.  into  a  contango 
of  5s.  By  these  means  they  succeeded  in 
carrying  their  position  without  paying  out 
heavy  differences.  Assisted  by  heavy  de- 
liveries of  Banka  and  small  shipments  from 
5—4 


the  East  they  gradually  forced  prices  up  to 
£\9\.  10s.,  but  their  purchases  have  had  an 
unnatural  appearance  and  create  distrust.  The 
month  closed  with  prices  down  to  /'187.  Con- 
sumption has  fallen  off  somewhat.  The  Welsh 
tinplate  industry  is  not  so  brisk  and  the  un- 
settled conditions  and  high  price  of  tin  is  det- 
rimental to  healthy  development.  In  America 
over-production  has  led  to  heavy  reductions 
of  price  in  the  home  trade,  and  has  forced  the 
mills  to  sell  for  export  in  competition  with 
Welsh  makers.  Dealings  on  the  new  stan- 
dard contract '  commenced  on  November  1. 

LEAD. 

Prices  of  soft  foreign  lead  : 

Oct.  1911.  Sept.  1911.         Oct.  1910. 

^15.  6s.  Id.  ^14.  15s.  Id.  ;^13.  2s.  Od. 
The  tendency  is  one  of  continued  strength, 
and  the  shortness  of  supplies,  already  acute, 
does  not  mend  with  time  ;  indeed  refineries 
are  overwhelmed  with  orders  and  are,  especi- 
ally in  America,  heavily  in  arrear.  The  Lon- 
don market  has  for  some  time  been  largely 
dependent  on  Australia,  but  the  announce- 
ment of  a  strike  of  wharf  labourers  there 
threatens  to  cut  off  these  supplies.  Consump- 
tion is  estimated  as  being  at  least  20%  in  ex- 
cess of  that  for  last  year. 

SPELTER. 

Average  prices  of  spelter  : 

Oct.  1911.  Sept.  1911.         Oct.  1910. 

^27.  4s.  lOd.      ^27.  12s.  7d.      ^23.  16s.  7d. 

High  prices  have  had  their  inevitable  result 
in  curtailing  demand  and,  as  we  foretold  in 
the  September  issue,  prices  have  turned.  Fol- 
lowing a  cut  in  the  price  of  sheets  the  Syndi- 
cate has  reduced  prices  20s.  "  with  a  view  to 
stimulate  demand,"  but  buyers  are  apathetic. 

OTHER  METALS  AND  MINERALS. 

Prices  quoted  on  November  7  : 

Silver. — 25id.  per  oz. 

Platinum. — 185s.  per  oz. 

Bismuth. — 7s.  6d.  per  lb. 

Aluminium. — ^53  per  ton. 

Nickel. — ;^170  per  ton. 

Cobalt. — 9s.  9d.  per  lb. 

Antimony. — £2d>  per  ton. 

Quicksilver. — £d,.  10s.  per  flask. 

Manganese  Ore. — 8d.to9id.  per  unit  (1%). 

Iron  Ore. — Cumberland  hematite  19s.  6d. 
per  ton  at  mine.    Spanish  20s.  delivered. 

Pig  Iron. — Cleveland46s.  9d.perton.  He- 
matite 61s.  per  ton. 

Wolfram  Ore— 30s.  per  unit  (1%). 


360 


THE    MINING    MAGAZINE 


PERSONAL 

A.  R.  Andrew  sailed  on  October  27  for 
New  Zealand. 

Philip  Argall,  general  manager  of  Strat- 
ton's  Independence,  is  here. 

William  Bach  left  London  on  October  21 
to  investigate  the  placer  deposits  of  Cuba. 

Rowland  Bancroft,  on  his  return  from 
South  America,  has  gone  to  Mexico. 

R.  T.  BAYLissleft  London  on  November  1 
for  Mexico.  On  his  return  he  will  proceed 
to  Rhodesia. 

Frank  K.  Borrow  proceeded  to  the  Fon- 
tino  &  Bolivia  mines  in  Colombia  on  Novem- 
ber 8. 

E.  H.  Brandt  left  London  on  October  25 
for  Monterey,  Mexico. 

R.  W.  Brock,  Director  of  the  Canadian 
Geological  Survey,  has  been  ill  with  fever  ; 
he  is  now  in  hospital  at  Vancouver. 

R.  Oilman  Brown  is  at  Kyshtim. 

George  B.  Butterworth  has  returned 
from  Northern  China. 

E.  W.  Byrde  is  now  with  the  Naraguta 
(Nigeria)  Tin  Mines,  in  Nigeria. 

Frederick  T.  Byrde  has  returned  from 
the  Gold  Coast. 

Gelasio  Caetani  is  in  Colorado. 

George  P.  Chaplin  has  returned  to  Lon- 
don from  British  Columbia,  where  he  has 
been  on  behalf  of  Bruce  Marriott  &  Co. 
|i(JJ.  H.  Collins  delivered  his  presidential 
address  to  the  Royal  Cornwall  Geological 
Society  on  October  31. 

I  )James  Douglas  will  give  a  lecture  on  the 
Copper  Queen  mine  before  the  Institution  of 
Mining  &  Metallurgy  on  November  23. 

Ralph  Ellis  has  gone  to  Buenos  Aires. 

Rowland  Feilding  now  has  his  office 
at  IS  St.  Swithin's  Lane. 

W.  B.  Fisher  has  moved  from  New  York 
to  Butte,  Montana. 

A.  J.  Eraser  has  returned  from  England 
to  Rhodesia. 

George  H.  Furner  has  resumed  his 
duties  as  manager  of  the  Zaaiplaats  tin  mine 
in  the  Northern  Transvaal  after  six  months 
holiday  in  England. 

Philip  Grimley  has  left  London  for 
Northern  Nigeria. 

Claude  V.  Haines  left  London  in  Octo- 
ber for  Portuguese  East  Africa. 

C.  W.  Hayes  has  resigned  from  the  U.S. 
Geological  Survey  to  be  advisor  for  S.  Pearson 
&  Son  in  Mexico. 

Frederick  Hellmann  sailed  for  New 
York  on  November  3. 


H.  W.  Hill  has  returned  from  the  Belgian 
Congo. 

Walter  T.  Holberton  left  on  October 
27  for  Chile,  to  return  in  February. 

Hooper,  Speak  &  Feilding  is  succeeded 
by  Hooper,  Speak  &  Co.,  with  offices  at  No. 
3  London  Wall  Buildings. 

H.  H.  Johnson,  of  Johnson  &  Hoffmann, 
has  returned  from  Porcupine. 

Howard  Johnson  has  returned  from 
Northern  Nigeria. 

S.  Ramplen  Jones  was  married  to  Miss 
Lucie  E.  Kruysboom  at  Colombo  on  August  1, 

F.  F.  Rett  has  gone  to  Nora,  Sweden,  as 
general  manager  for  the  Swedish  Iron  Mines 
&  Furnaces,  Ltd. 

Ernst  Lichtenberg,  on  his  return  from 
Austria,  has  been  ill,  but  is  now  convalescent. 

W.  J.  LoRiNG  and  J.  Malcolm  Mac- 
laren  have  been  inspecting  mines  in  Cali- 
fornia. 

E.  D.  McDermott  has  returned  from 
Kyshtim. 

DiGHTON  MiCHAUX  after  being  for  a  year 
in  Katanga  has  returned  to  Rhodesia. 

William  C.  Mountain  has  opened  an 
office  as  consulting  engineer  at  Newcastle-on- 
Tyne,  devoting  his  attention  specially  to  the 
application  of  electricity  to  mines. 

John  C.  Pickering  sailed  for  Cape  Town 
on  his  way  to  Rhodesia  on  October  21. 

H.  A.  Piper  has  returned  from  Rhodesia. 

C.  W.  Purington  returned  from  Eastern 
Siberia  on  November  10. 

H.  M.  Ridge  has  returned  from  British 
Columbia. 

O.  J.  Steinhart  has  returned  from  Swe- 
dish Lapland. 

S.  J.  Truscott  has  moved  to  27  Austin 
Friars,  London,  E.C. 

E.J.  Vallentine, manager  of  the  Rahman 
tin  mine,  in  the  Malay  States,  is  due  in  Lon- 
don on  November  15. 

D'Arcy  Weatherbe  is  now  at  St.  Peters- 
burg but  will  be  in  London  in  December. 

George  E.  Webber  sailed  for  New  York 
on  his  way  to  California  on  November  4. 

R.  Hansford  Worth  is  consulting  engi- 
neer to  the  China  Clay  Corporation  in  con- 
nection with  the  development  of  their  property 
in  South  Devon. 

Lewis  T.  Wright,  recently  manager  for 
the  Mountain  Copper  Co.,  is  in  London. 

Readers  appreciating  this  magazine  way 
give  their  friends  the  opportunity  of  seeing 
a  copy.  We  will  send  a  specimen  copy  to 
any  address  on  receipt  of  a  written  appli- 
cation. 


MILLING  METHODS  ATSTRATTON'S  INDEPENDENCE 

By    PHILIP  ARGALL. 


Introductory.— In  mining  and  shipping 
some  §20,000,000  worth  of  gold  ore,  from  the 
Stratton's  Independence  mine,  something  like 
one  million  tons  of  refuse  was  sorted  out  and 
deposited  on  the  dumps.  This  material  was 
generally  assumed  to  average  about  $4  per 
ton,  but  as  was  to  be  expected,  the  content  is 
quite  variable;  some  of  it  has  reached  $5, 
much  of  it  has  not  exceeded  half  that  value, 
while  the  average  will  probably  not  exceed 
$3'25  per  ton. 


I  went  back  to  my  first  experiments  on  Cripple 
Creek  ores  made  in  the  autumn  of  1893,  and 
m  the  following  spring.  In  these  tests  con- 
centration was  the  dominant  feature.  These 
early  experiments  in  part  formed  the  basis  for 
my  review  of  cyanidation  published  in  the 
Engineering  Magazine,  New  York,  in  Sep- 
tember 1894,  from  which  it  is  perhaps  per- 
missible to  quote : 

"  In  other  cases  concentration  is  advisable.     For 
example  :  An  ore  may  contain  15%  of  pyrite,  which 


THE    STRATTON'S    INDEPENDENCE    MILL. 


The  directors  of  Stratton's  Independence, 
Ltd.,  as  early  as  1903  had  experiments  made 
looking  to  the  beneficiation  of  this  ore  ;  an 
experimental  mill  was  later  erected,  the  ore 
was  treated  by  various  methods,  and  the 
dumps  sampled. 

In  November  1906  I  was  engaged  to  ex- 
amine and  report  on  the  treatment  of  this  low- 
grade  sulpho-telluride  ore,  and  naturally  looked 
into  the  use  of  the  various  processes,  but  soon 
found  that  no  chemical  then  available  would 
assure  satisfactory  treatment  ;  consequently, 


may  require  special  treatment  in  the  way  of  a  stronger 
solution,  or  long  exposure  to  solution — say,  80  hours 
— in  order  to  obtain  a  good  extraction  ;  while  the 
remaining  85%  of  the  ore  may  have  its  gold  dis- 
solved in  24  hours.  Here,  then,  separating  the 
heavier  from  the  lighter  particles,  and  subjecting 
each  to  separate  treatment,  will  result  in  a  gain  of 
time  in  lixiviating,  saving  of  chemicals,  and  in- 
creased capacity  of  the  works.  The  same  line  of 
argument  holds  good  if  the  concentrate  cannot  be 
successfully  treated  by  cyanide,  as  in  this  case  a 
deleterious  material  is  removed  from  contact  with 
the  cyanide  solution,  to  be  handled  by  such  other 
methods  as  the  particular  circumstances  will  indi- 
cate.    The  cyanide  process,   then,  can  be  applied 


361 


362 


THE    MINING    MAGAZINE 


to  ores  direct,  or  as  a  combination  process  with 
amalgamation  or  concentration,  or  both,  as  may  be 
found  most  convenient  and  profitable." 

The  concentration  method  was  adopted  and 
my  original  experiments  brought  to  the  fore, 
after  a  lapse  of  13  years.  In  the  interval, 
mechanical  progress  in  crushing,  in  concen- 
trating and  in  cyaniding  machinery,  had  been 
marked;  but  not  much  advance  had  been  made 
in  the  substitution  of  cyanide  solution  for  water 
in  the  entire  millmg  process — an  advantage  I 
had  seen  and  tried  in  the  early  'eighties,  and 
still  favoured.  Experiments  on  these  lines 
were  therefore  in  order  ;  and  on  their  com- 
pletion on  a  laboratory  scale  I  reported  to  the 
directors  of  Stratton's  Independence,  Ltd., 
that  a  mill  of  10,000  tons  per  month  could 
treat  the  ore  for  $r52  per  ton,  including  10c. 
per  ton  for  mining;  giving  an  extraction  of 
about  70%  of  the  contained  value,  then  esti- 
mated between  $3"60  and  $3'80  per  ton. 

A  mill  with  a  capacity  of  5000  tons  per 
month  was  planned,  and  duly  erected,  tested 
completely,  and  later  enlarged  to  its  present 
capacity  of  10,000  tons  per  month. 

The  process  is  as  follows :  Coarse  crushing 
in  Gates  gyratory  breakers,  medium  crushing 
in  36  in.  rolls,  fine  crushing  in  Chilean  mills. 
Cyanide  solution  is  added  in  the  Chileans,  and 
thenceforward  the  process  is  crushing  and 
concentrating  in  cyanide  solution  in  a  closed 
circuit.  The  pulp  from  the  Chilean  mills  is 
separated  into  sand  and  slime  in  Ovoca  classi- 
fiers, the  former  is  treated  on  20  Card  tables, 
the  latter  on  12  No.  3  Deister  slime-tables, 
and  4  suspended  vanners.  A  first  and  second- 
class  concentrate  is  produced,  the  latter  being 
re-treated  on  Card  and  Deister  tables,  produc- 
ing more  first-grade  and  a  middling  product 
that  is  returned  to  a  tube-mill  and,  after  grind- 
ing, joins  the  pulp  issuing  from  the  Chilean 
mills  and  circulates  in  the  main  circuit  of  the 
mill,  finding  its  position  in  sand  and  slime. 

For  details  consult  flow-sheet  and  the  fol- 
lowing legend  : 

1.  Double-track  inclined  plane. 

2.  No.  7i  Gates  gyratory  breaker. 

3.  Picking-belt  3  ft.  wide. 

4.  No.  5  Gates  breaker. 

5.  18  in.  conveyor-belt. 

6.  16  by  36  in.  rolls. 

7.  Stock-bins  above  Chilean  mills. 

8.  Thickening-cones. 

9.  No.  3  Deister  slime-table. 

10.  Suspended  vanners. 

11.  Vacuum-filters. 

12.  Precipitators. 

13.  Tube-mill. 


F.  Elevator  lifting  slime  '  seconds'  for  re- 

concentration. 

G.  Centrifugal  pump   lifting  tailing  from 

second  concentrate  for  tube-milling. 
After  concentration,  the  sand  and  solution 
in  which  it  was  concentrated  are  pumped  to 
the  cyanide  department,  the  solution  being 
separated  and  the  sand  automatically  distri- 
buted in  leaching- vats,  O  1  to  0  6.  After 
treatment  the  sand  is  sluiced  to  the  tailing- 
reservoir.  The  middling  from  the  finishing 
tables  not  furnishing  sufficient  supply  for  a 
5  by  14  ft.  tube-inill,  two  spigots  are  drawn  oft 
from  the  sand  on  its  way  to  the  cyanide  de- 
partment ;  this  is  a  partly  concentrated  pro- 
duct, being  the  heavier  sand  that  tends  to  fol- 
low the  bottom  of  the  slightly  inclined  pipe. 

The  slime  passes  from  the  Ovoca  classifier 
to  16  thickening-cones  ;  the  thickened  product 
is  automatically  distributed  over  the  Deister 
and  vanner  tables  in  a  similar  manner  to  the 
sand,  the  second-grade  re-concentrated  and 
the  middling  ground  in  the  tube-mill  before 
again  joining  the  main  pulp-stream  circulating 
through  the  mill.  The  tailing  from  the  slime- 
tables  is  pumped  to  an  overflow-cone  in  the 
cyanide  department  and  distributed  by  laun- 
der L  to  four  continuous  settling-vats,  S  1  to 
S  4,  the  product  being  a  thickened  slime  and 
a  clear  -  solution  overflow.  The  thickened 
slime  is  pumped  to  S  6  for  final  treatment  by 
cyanide  solution,  and  when  required,  to  S  7  for 
bromo  -  cyanide  treatment.  From  either  of 
these  vats  the  slime  is  piped  to  S  5,  which  sup- 
plies the  vacuum-filters.  From  here  the  slime- 
cakes  pass  to  the  dump  and  the  pregnant  solu- 
tion to  the  clarifying  press  (p),  thence  through 
the  precipitators,  the  barren  solution  dropping 
into  an  underground  sump,  from  which  it  is 
circulated  for  distribution  over  the  concentra- 
ting-tables;  in  other  words,  the  barren  solution 
is  used  as  table-water. 

Following  the  solution,  it  will  be  noted  from 
the  flow -sheet  that  the  cyanide  solution  in 
storage-vat  B  is  fed,  together  with  the  ore,  to 
the  Chilean  mills,  that  75%  of  it  separated 
with  the  slime  passes  out  of  the  Ovoca  classi- 
fier to  the  thickening-cones.  The  slime-tail- 
ing with  the  solution  added  to  it  in  the  concen- 
tration process  is  pumped  to  a  cone,  the  over- 
flow passing  to  launder  L  in  the  cyanide  de- 
partment, while  the  clear -solution  overflow 
from  vat  S  1  to  S  4  returns  to  the  storage-vat 
B  for  another  circuit.  Returning  now  to  the 
sand  emerging  from  the  head  of  the  Ovoca 
classifiers  C  1  and  C  2,  it  is  immediately  diluted 
with  clear  solution  direct  from  storage  B,  which 
carries  the  sand   to    the    central  distributor, 


NOVEMBER,    1911 


363 


^1 


5 


n 


j__      « /u 


(C 


}- 


364 


THE    MINING.  MAGAZINE 


which  in  turn  provides  a  direct  supply  for 
each  of  the  20  Card  tables ;  on  these  tables 
barren  cyanide  solution  is  used  for  dressing 
the  ore,  passing  with  the  tailing  to  classifiers 
C  4  and  C  5.  The  slime-overflow  from  these 
latter  enters  launder  L  and  becomes  the  main 
slime-circuit,  giving  a  clear-solution  overflow 
from  the  vats  S  1  to  S  4,  which  passes  direct 
to  storage  B  for  another  round  in  the  closed 
circuit  of  the  mill-solution. 

This  solution  is  constantly  dissolving  gold 
in  its  circuit  through  the  mill,  and  as  the  aim 
is  to  not  allow  its  gold  content  to  exceed  $1 
per  ton,  part  of  the  clear  overflow  from  vats 
S  1 — S  4  is  continuously  passed  through  the 
clarifying  presses  {p,p)  and  the  precipitators 
(12),  finally  reaching  the  sump  as  barren  solu- 
tion, from  which  it  circulates  to  the  tables,  as 
previously  described,  joining  the  main  pulp- 
stream,  and  thus  reducing  the  gold  in  the  cir- 
culating solution.  The  barren  solution  is  also 
used  for  washing  the  sand  charges  in  the 
leaching-vats.  The  bulk  of  the  gold  is,  how- 
ever, usually  recovered  by  the  special  treat- 
ment of  the  thickened  ^lime  in  S  6  and  S  7, 
where,  after  thorough  agitation,  it  passes 
through  S  5  to  the  vacuum-filters,  clarifying 
presses  {p)  and  precipitators  (12),  the  barren 
solution  reaching  the  sump  preparatory  to 
making  another  circuit  through  the  mill.  Fin- 
ally, the  pregnant  solution  from  the  sand-leach- 
ing vatsO  1  to06is  piped  back  to  the  precipita- 
tors, reaching  the  sump  as  barren  solution, 
while  the  final  wash-water  passes  to  waste 
through  a  special  precipitator. 

The  process,  it  will  be  seen,  is  crushing  and 
concentrating  in  cyanide  solution  in  a  closed 
circuit,  in  combination  with  incomplete  pre- 
cipitation, so  that  the  circulating  solution  shall 
never  exceed  $1  per  ton,  and  shall  average 
about  50  c.  per  ton.  It  will  be  noted  that  com- 
plete precipitation  is  unnecessary  inasmuch  as 
both  sand  and  slime  are  subjected  to  further 
cyanide  treatment  and  water- washes  before 
passing  to  the  dump. 

Having  now  described  our  milling  method 
and  flow -sheet,  I  shall  proceed  to  describe 
some  of  the  more  important  operations  in  de- 
tail. 

Mining. — The  dump  is  situated  on  a  hill- 
side traversed  by  deep  depressions,  giving  an 
irregular  and  uncertain  bottom  ;  the  ore  is 
usually  frozen  near  the  bottom  all  the  year 
round  and  in  winter  requires  considerable 
blasting  to  prepare  it  for  the  shovel.  The 
ore  is  loaded  into  4-ton  cars  by  a  power-shovel 
with  dipper  of  1  cu.  yd.  capacity,  the  machme 
being  operated  by  one  40  hp.  variable  speed 


electric  motor,  from  which  the  digging,  crowd- 
ing, swinging,  and  advancing  motion  are  all 
derived  by  clutch-gearing  controlled  by  levers 
operated  by  one  man.  By  official  test  the 
machine  easily  handled  120  tons  per  hour.  In 
daily  work,  however,  loading  small  cars  where 
the  dipper  has  to  be  spotted  each  time  before 
dumping,  we  find  60  tons  per  hour  about  the 
average  capacity,  though  we  often  reach  75 
tons  per  hour  with  an  expert  operator.  The 
ore-cars  are  hoisted  up  an  incline  plane  and 
automatically  dumped  into  a  No.  7i  Gates 
breaker;  this  ends  the  mining  and  delivery  at 
the  mill,  the  cost  of  which  is  .f  0'0891  per  ton, 
divided  as  follows : 

Per  ton 

Power 161000         »00217 

Operating  labour 133504  00476 

supplies 1360  00005 

Repairs   labour 353  25  0  0125 

supplies 189-74  00068 

28,078  tons f250r63  0  0891 

Ore-Breaking. — The  ore  is  broken  in  the 
1\  Gates  machine  to  about  4  in.  cube,  the  fine 
removed  by  grizzly,  the  coarse  conveyed  on  a 
picking-belt  to  a  No.  5  Gates  breaker,  in  which 
it  is  reduced  to  about  li  in.  cube,  and  con- 
veyed direct  to  the  300-ton  storage-bin,  to- 
gether with  the  fine  removed  by  the  grizzly. 
The  ore  cannot  be  enriched  much  by  sorting, 
the  waste  picked  out  seldom  reaching  3%.  Of 
more  importance  is  the  steel  and  wood  removed 
at  this  point,  for  these  would  otherwise  seri- 
ously interfere  with  subsequent  milling  opera- 
tions. This  breaker-plant  is  operated  with  the 
power-shovel  and  inclined  plane  about  6  hours 
per  day.  The  total  cost  is  !?0'1633  per  ton,  of 
which  the  sorting  or  picking  amounts  to,  say, 
$0'04. 

Coarse  crushing  is  accomplished  in  two 
sets  of  36  by  16  in.  rolls,  operated  in  series, 
having  a  capacity  of  30  tons  per  hour  from 
li  to  4  inch.  The  storage-bins  in  front  of  the 
Chilean  mills  not  having  capacity  for  a  16 
hours  run,  the  roll-plant  is  operated  during 
part  of  two  shifts  each  day,  and  in  order  to 
have  more  men  in  the  mill  on  the  night  shifts, 
the  rolls  are  operated  on  the  second  and  night 
shifts  by  one  man  per  shift,  who  also  attends 
to  general  repairs.  Probably  one  of  the  best 
things  in  this  department  is  the  300-ton  self- 
supporting  steel  storage-bin  (Fig.  l)  the  simp- 
lest and  most  satisfactory  ore-bin  I  ever  used. 
It  is  thoroughly  automatic,  the  last  pound  will 
come  out  without  the  use  of  crow-bar  or  shovel. 
The  feeder  is  of  the  revolving-table  type,  sub- 
ject to  two  variations  :  thickness  of  feed  by 
adjusting  the  height  of  the  annular  sleeve  at 


NOVEMBER,    1911 


365 


bottom  of  the  feed-cone,  and  width  of  annulus 
cut  off  by  the  adjustable  plough  ;  the  feed  is 
also  steady  and  continuous,  an  important  mat- 
ter m  feeding  rolls.  It  will  be  noted  that  the 
opening  in  the  bottom  of  the  ore-bin  is  large 
(4  ft.  diam.),  hence  it  is  ample  to  prevent  any 
semblance  of  a  choke,  and  small  enough  to  re- 
lieve the  feed-cone  from  excessive  pressure. 
The  relation  between  the  4  ft.  opening  in  the 
bottom  of  the  main  bin,  the  diameter  of  feed- 
cone  top  and  its  1  ft.  diam.  bottom  opening 
just  above  the  revolving  table  of  theore-feeder, 
are  important  points  to  observe.  The  ore 
stored  in  this  bin  is  reduced  to  less  than  2  in. 


Fig.  1.     Steel  Storage-Bin. 

cube  and  is  fed  to  the  rolls  at  the  rate  of  30 
tons  per  hour.  The  ore  is  moistened  with 
cyanide  solution  on  the  table  of  the  feeder  to 
lay  the  dust  and  slack  the  lime  that  is  added 
dry  at  this  point  by  another  automatic  feeder. 
The  lime  is  thus  well  incorporated  with  the 
ore  in  passing  through  the  rolls,  and  at  once 
begins  its  work  of  neutralization  in  the  damp 
ore,  which  is  then  elevated  to  the  storage-bins 
above  each  Chilean  mill,  supposedly  reduced 
to  i  in.,  but  more  nearly  f  inch.  It  should  be 
stated,  however,  that  the  ore  is  mostly  phono- 
lite  and  breaks  in  thin  flakes,  that  most  of  the 
coarse  caught  on  h  in.  aperture  screens  would 
be  less  than  j  in.  thick,  hence  easily  crushed 


by  the  rollers  in  the  Chilean  mills.  As  origin- 
ally designed  the  ore  from  the  second  roll  was 
passed  through  screens  with  fin.  aperture; 
but  this  was  found  to  be  an  unnecessary  re- 
finement, so  the  screens  were  removed  and 
the  cost  of  the  screening  operation  eliminated. 
Fine  Crushing.— This  plant  consists  of 
four  Akron  Chilean  mills  of  6  ft.  diam.  (Fig. 
3),  three  of  which  easily  give  the  capacity  re- 
quired :  10,000  tons  per  month.  The  fourth 
is  held  in  reserve  until  needed  to  take  the 
place  of  either  of  the  others.  These  mills 
crush  from  100  to  130  tons  per  day,  depending 
on  the  feed,  the  character  of  the  ore  and  the 
screens  used  ;  with  a  screen  of  0'046  in.  aper- 
ture 0"054  wire  and  speed  of  33  r.p.m.,  the 
capacity  is  almost  3  tons  per  hour  for  an  ex- 


Fig.  <?.    Pneumatic  Agitator. 

penditure  of  55  hp.  The  power  consumed  by 
Chilean  mills  depends  chiefly  on  the  amount 
and  size  of  the  ore  fed  to  them  ;  secondly,  on 
its  crushing  qualities.  Using  relative  terms, 
with  a  supply  of  finely  comminuted  ore  the 
power  will  be  much  less  than  that  required  for 
a  coarse  product,  which  offers  greater  resist- 
ance to  the  rollers,  even  causing  them  to  rise 
from  the  die  and  occasionally  ride  over  coarse 
tough  particles  ;  then  again,  the  resistance  is 
less  with  a  shallow  thin  feed  in  the  mill,  less 
power  is  required  to  operate,  and  tlie  crushing 
capacity  is  also  less.  For  a  6  ft.  Akron  mill 
operating  on  average  ore  crushed  to  about 
i  in.,  I  would  provide  a  50  hp.  motor  guaran- 


366 


THE    MINING    MAGAZINE 


teed  for  20%  overload.     The  following  tests 
are  instructive : 

The  line-shaft  driving  two  6  ft.  Akron  mills 
is  operated  by  a  100  hp.  motor  ;  one  of  these 
mills  was  thrown  off,  and  the  tests  made  on 
the  other. 

Input  to  Motor 
hp. 

Motor  and  line-shaft 4 

Motor  line-shaft  and  Chilean  mill,  repre- 
senting the  friction  load 9 

Light  feed  5  to  g  in.  product  to  the  mill...   28 

Heavy  feed,  mill  a  little  crowded  but  in 
good  running  condition 63 

The  mill  was  next  fed  to  the  limit, 
crowded,  in  fact,  almost  to  the  stall- 
ing point 70 

The  foregoing  results  from  average  of 
reading  every  few  minutes,  for  one 
half  -  hour.  A  watt  -  meter  was  next 
placed  in  the  motor-circuit  and  gave, 
on  a  23-hours  test 52 

On  317^  hours  test  (April  5  to  18,  1911)...  53 

The  mill  was  in  average  condition,  and 
during  the  wattmeter  tests  was  fed  and  oper- 
ated under  our  usual  milling  conditions,  giving 
an  average  output  of  115  tons  per  day,  of  the 
following  composition  : 

.•\perture 

Mesh                                                     Inch  % 

Plus        50 00096  21 

100 0  0056  12 

150 0  0030  5 

Minus  150 0  0030  62 

The  Chilean  mill  is  an  admitted  slimer,  yet 
it  is  not  by  any  means  as  bad  as  painted.  I 
would  call  it  an  efficient  crusher  that  is  cap- 
able of  adjustment,  within  certain  limits,  to 
give  a  fine,  yet  granular,  product.  The  com- 
minution of  ore  in  a  Chilean  mill  may  be  said 
to  be  the  resultant  of  two  forces,  the  direct 
■crushing  effect,  due  to  the  weight  and  speed 
of  the  rollers,  the  grinding  or  abrading  effect, 
due  to  the  rollers  being  constrained  to  travel 
in  a  circular  path  ;  hence,  they  partake  of  two 
motions  ;  rotary,  around  their  individual  axles, 
and  annular,  around  the  die,  concentric  to  the 
central  axis  of  the  mill. 

Let  us  look  into  the  latter.  A  circle  drawn 
on  the  face  of  the  die-ring  4  in.  from  the  side 
(shown  in  cross-section  at  c),  and  a  line  drawn 
around  the  face  of  the  roller  tire  4  in.  from  the 


Tire 
Die 


< 

8'"     -  , 

^^^^ 

^ 

A 


Sand* 


side  (similarly  shown  at  d),  represents  the 
lines  of  maximum  wear  on  tires  and  die  in  a 
Chilean  mill.  The  corrugations  in  the  8  in. 
crushing-faces  reach  their  maximum  approxi- 
mately along  these  lines. 


A  section  of  new  steel  is  shown  at  A,  while 
B  shows  the  worn  steel.  Why  should  the 
steel  wear  in  this  manner  ?  The  answer  is 
twofold.  First,  the  coarser  ore  is  dropped 
from  the  feed-pipe  approximately  along  the 
circle  c  of  the  die,  and  forms  a  ridge ;  the 
principal  reason  is,  however,  the  grinding  or 
abrading  action  occurring  there.  A  roller,  in 
making  the  circuit  of  the  die,  also  completes 
a  revolution  on  the  line  ^at  right  angles  to  its 
axis  of  rotation.  It  is  this  annular  direction 
of  the  rollers,  deflecting  them  from  a  straight 
course  and  pure  rolling  motion  that  causes  the 
grinding  or  abrading  effect ;  the  smaller  the 
diameter  of  the  die,  the  greater  is  the  abrading 
effect  or  twist  on  the  ore  particles  held  be- 
tween the  die-ring  and  the  tire  of  the  rollers ; 
on  the  other  hand,  the  greater  the  diameter  of 
the  die  the  more  nearly  the  rollers  approach  a 
pure  rolling  motion  with  lessened  abrasion  and 
lowered  efficiency  as  a  fine  crusher,  or  slimer, 
if  you  will.  For  this  reason  the  so-called 
*  slow-speed  mills '  with  large  diameter  die- 
rings  are  not  slimers  and  scarcely  come  within 
the  fine-crushing  class,  they  approximate  more 
nearly  the  work  of  rolls  than  that  of  Chilean 
mills.  In  these  the  roller  receives  its  rotary 
motion  through  friction  with  the  ore  on  the 
die-ring,  the  line  d  around  the  centre  of  the 
tire -face  theoretically  should  roll  upon  the 
fragments  while  the  outer  margins  of  the  tire- 
face  slide  over  them  ;  as  the  roller  advances, 
constantly  bending  inward  from  a  straight 
path,  its  outer  flange  crowds  the  ore  in  front, 
inward  on  the  die,  its  rear  outward  on  the 
screen,  particularly  after  corrugation  is  estab- 
lished. In  our  mills  we  have  abandoned  the 
use  of  scrapers  depending  solely  on  the  wheel- 
splash  for  the  screening  effect. 

The  capacity  of  the  Chilean  mill  increases 
slightly  as  the  steel  wears,  as  does  also  the 
power  ;  but  these  are  balanced  somewhat  by 
the  lessening  weight  of  the  rollers  due  to  tire 
wear  ;  with  both  die-ring  and  tires  corrugated, 
as  in  jB,  the  Chilean  mill  usually  gives  its 
maximum  efficiency  as  a  fine  grinder  inas- 
much as  both  the  twisting  (abrading)  action 
and  the  weight  of  the  roller  is  effective  on  all 
ore  held  in  the  corrugations,  not  on  a  thin  film 
as  where  smooth  (new)  tires  are  in  use.  Rolls 
differ  from  Chilean  mills  in  this  respect  :  when 
corrugated  their  capacity  lessens ;  still,  by 
what  I  have  elsewhere  described  as  the 
'choke-feed,"  they  can  be  made  to  treat  a  thick 
stream,  grinding  the  dry  ore  upon  itself  with 
increased  capacity  and  finer  product.  The 
Chilean  mill,  however,  will  do  all  this  wet,  and 
do  it  belter.     This  is  at  once  the  secret  of  its 


NOVEMBER,    1911 


367 


success  as  a  fine  crusher  and  the  cause  of  its 
sliming  action.  For  fine  comminution,  attri- 
tion in  some  form  is  necessary  ;  in  hand- work 
(cutting  down  samples,  for  example)  a  hammer 
can  be  used  effectively  for  a  time,  but  on  the 
bucking-board  every  one  believes  in  the  grind- 
ing action  of  the  muller.  The  machine  that 
depends  on  a  blow  alone  cuts  but  a  sorry 
figure  in  fine  crushing,  and  should  not  be 
classed  with  such  machinery.  For  this  reason 
I  have  long  held  that  the  stamp  is  not  a  fine 
crusher  because  most  of  its  work  is  done  by 
impact,  and  but  little  by  attrition,  a  fact  that 
is  gradually  being  recognized. 

Rolled  steel  tires  and  dies  have  proved  best 
in  our  practice,  such  for  example  as  the  Mid- 
vale  and  Latrobe  brands.  The  wear  and  loss 
of  steel  on  last  year's  campaign  of  87,814  tons 
crushed,  works  out  as  follows  : 

lb.  %  % 

Tire  Steel  worn 0  367  59'2 

Tire  steel  scrap 0063  10  1 

043       69  3 

Die  steel  worn 0  153  248 

Die  steel  scrap 0  037  59 

0-19      307 

Total  steel  per  ton  crushed   062  lb.  lOO'O 

The  crushing  pressure  in  the  Akron  mill  is 
fairly  heavy.  Assuming  a  roller  rests  in  ore,  on 
the  die,  for  one  inch  of  its  circumference  ;  or, 
in  other  words,  crushes  one  square  inch  of  ore 
per  inch  of  face  ;  then  the  crushing  pressure 
on  the  6-ft.  mill  is  about  900  lb.  per  sq.  in., 
the  roller  with  a  new  steel  tire  of  8  in.  face 
weighing  about  7200  lb.  The  crushing  pres- 
sure is  no  doubt  augmented  slightly  by  centri- 
fugal force,  particularly  if  the  rollers  are  run 
with  a  slight  inward  inclination  on  top.  One 
great  advantage  of  the  Akron  mill  is  the  ease 
with  which  the  rollers  can  be  adjusted  and  the 
drive-head  raised  or  lowered  while  the  mill  is 
running.     See  Fig.  3. 

Tellurides  are  friable,  and  while  the  fine 
is  richer  than  the  coarse  ore  in  most  cases,  yet 
the  ores  of  Cripple  Creek  afford  the  greatest 
contrast  in  this  respect.  From  the  lumps  that 
will  pass  through  a  2  in.  grizzly  to  the  dust 
caught  in  the  rafters  of  the  mill  the  finer  pieces 
and  particles  are  invariably  the  richer.  Ad- 
vantage has  been  taken  of  this  fact,  and  exten- 
sive experiments  conducted  to  determine  the 
best  method  of  crushing  and  the  most  econo- 
mical size  of  reduction.  It  was  recognized 
from  the  first  that  Cripple  Creek  sulpho-tellu- 
rides  were  most  difficult  to  cyanide  by  any 
method  known  to  me,  apart  from  roasting, 
consequently  concentration  was  chosen  as  the 
sheet  anchor  of  the  process,  and  every  effort 


was  put  forth  to  remove  by  concentration,  in 
advance  of  the  final  cyanide  treatment,  all  the 
sulpho-tellurides  possible  in  both  slime  and 
sand. 

The  ore  of  Stratton's  Independence  appears 
at  first  glance  to  consist  of  a  rather  sparse 
scattering  of  sulphides  in  phonolite  and  phono- 
litic  breccia;  on  closer  examination  it  is  found 
that  the  gold  occurs  chiefly  as  films  along 
fracture -planes,   or   in   cavities,   or  in   small 


l^l<>rm 


Fig.  -i.     Section  oj  Akron  Chilian  Mill. 

veinlets  ;  the  sulphide  in  the  body  of  the 
rock  is  invariably  low-grade,  and  occasionally 
worthless.  To  crush  the  rock  fine  enough  to 
liberate  all  the  sulphides  was  out  of  the  ques- 
tion on  account  of  the  cost,  the  dressing  loss 
in  concentirating  slime,  and  the  low-grade  pro- 
duct obtained  from  the  concentrators.  Ex- 
periments were  made  with  rolls,  stamps,  pans, 
and  Chilean  mills,  the  latter  giving  the  best 
results.  Then  followed  experiments  with  size- 
crushing  on  a  full  working  scale,  made  through 
screens  varying  from  0*02  to  O'lO  in.  aperture. 


368 


THE    MINING    MAGAZINE 


The  best  average  results  were,  however,  ob- 
tained around  0"046  screen  aperture,  which  on 
$3'25  ore  give  us  a  sand-tailing  averaging, 
after  concentrating,  about  80  c.  per  ton,  and  a 
slime  running  about  $2  per  ton  after  concen- 
tration, both  products  being  subjected  to  fur- 
ther cyanide  treatment.  We  have  always 
failed  to  get  any  of  the  slime-tailings  as  low 
as  the  sands,  either  in  the  concentrating  or  in 
the  cyaniding  department.  Another  argument 
against  further  reduction  of  the  sand  might  be 
predicated  on  this  fact. 

The  guide,  chosen  after  months  of  experi- 
ment, is  not  to  allow  the  sand-tailing  from  the 
table  to  exceed  $1  per  ton  ;  when  this  limit  is 
approached  a  finer  screen  is  used  on  the  mills. 
Comparatively  coarse  crushing,  and  elimina- 
ting 40  to  50%  of  the  ore  as  sand,  with  a  poorer 
tailing  than  we  can  obtain  from  the  slime,  is 
one  of  the  nice  points  in  our  practice,  not 
generally  seen  or  at  least  understood  by  either 
the  casual  observer  or  the  critic.  Here  the 
physical  character  of  the  ore  is  utilized  to  ob- 
tain :  (7)  a  coarse  sand  from  which  a  high- 
grade  concentrate  (carrying  5  to  7  oz.  gold) 
and  an  almost  worthless  tailing  is  produced  in 
one  operation  ;  (2)  An  enriched  slime  from 
which  a  high-grade  concentrate  can  also  be 
obtained,  leaving  but  50  to  60%  of  the  original 
ore  for  special  treatment,  such  as  air  agitation, 
oxidizing  chemicals,  and  filtration. 

Concentration.  —  The  sand  from  the 
Ovoca  classifiers  is  automatically  distributed 
to  20  Card  tables  or  any  lesser  number,  the 
machine  being  so  arranged  that  one  or  more 
tables  can  be  eliminated  by  merely  inserting 
plugs  in  the  divisions  of  the  classifiers  supply- 
ing them,  while  the  supply  of  the  idle  tables 
is  automatically  distributed  over  the  tables  in 
operation.  This  distributor,  as  improved  by 
the  mill  superintendent,  is  about  the  best  I 
have  seen.  A  similar  one  distributes  the 
slime,  and  largely  through  their  use  one  man 
on  shift  attends  to  22  sand-tables,  4  vanners, 
and  13  Deisters.  The  tables  once  adjusted 
require  but  little  attention  so  long  as  the  feed 
and  table-water  are  regular.  Originally  the 
sand  was  divided  into  plus  and  minus  40  mesh 
product,  but  the  screens  proved  troublesome 
and  expensive  to  maintain  ;  later  we  found 
that  just  as  good  concentration  could  be  done 
without  them  ;  our  present  practice  is  to  make 
but  one  sand  product  and  one  thickened  slime. 
From  careful  trials  made  in  1907  I  decided 
that  the  Card  table  gave  the  best  result  on 
our  sand,  and  I  have  been  quite  satisfied  with 
its  performance  in  the  mill.  The  No.  3  Deis- 
ter  has  done   equally  as  good  work   on  our 


slime  as  the  modern  vanner,  and  at  less  than 
one-tenth  the  maintenance.  Vanner-belts  do 
not  last  in  our  solution  over  9  months  ;  they 
cost  about  $120  delivered  ;  this  item  alone 
would  maintain  a  Deister  table  for  several 
years.  Then  the  rollers,  gears,  etc.,  on  the 
vanners,  require  careful  attention,  and  are  a 
source  of  constant  expense. 

I  have  shown  how  the  residual  value  of  the 
sand  is  controlled  by  the  size  of  the  aperture 
in  the  screens  of  the  Chilean  mills  ;  we  have, 
however,  another  controller  in  the  second  con- 
centrate produced  on  the  general  tables,  inas- 
much as  by  drawing  off  a  greater  or  smaller 
amount  of  '  seconds '  and  middlings  for  re- 
concentration  and  re- grinding  all  the  tail  in  a 
tube  -  mill,  the  tailing  discharged  from  the 
general  tables  is  largely  modified.  Further- 
more, it  is  obvious  that  the  production  of  this 
second-class  material  for  re-concentration  and 
tube-milling,  renders  possible  the  compara- 
tively coarse  crushing  in  the  Chilean  mills, 
through  which  a  high  saving  of  granular 
sulpho-telluride  is  made,  that  if  slimed  in  the 
first  instance  would  entail  a  great  decrease  in 
the  gold  recovered  by  concentration  and  in- 
cidentally a  higher  final  tailing  from  the  cya- 
nide plant.  To  summarize,  crushing  through 
10  mesh  0'046  aperture  screens  is  made  pos- 
sible by  returning  a  concentrated  middling 
product  for  re-grinding  in  a  tube-mill  prepara- 
tory to  again  entering  the  main  circuit  of  the 
mill. 

Cyanidation.  —  After  concentration  the 
various  sands  are  pumped  to  the  Ovoca  classi- 
fiers C  4  and  C  5  in  the  cyanide  department, 
to  be  separated  from  the  final  traces  of  slime. 
These  classifiers  give  a  sand  practically  free 
from  slime  and  carrying  from  15  to  25%  mois- 
ture, as  desired  ;  they  consequently  perform  a 
double  service,  slime  separation,  and  sand  de- 
watering.  The  clean  sand  delivered  at  the 
head  of  the  classifiers  is  mixed  with  as  much 
barren  solution  as  will  pass  through  the  vat- 
filters  during  the  filling  process  and  sluiced 
through  highly  inclined  launders  to  fixed  points 
over  the  empty  leaching-vats,  or  is  moved 
there  by  reciprocating  conveyors  when  suffi- 
cient fall  cannot  be  obtained  for  launders ;  in 
either  case  the  maximum  solution  that  will 
pass  the  filters  is  brought  with  the  sand  to 
aid  the  distribution  in  the  vats.  Meanwhile, 
leaching  continues  throughout  the  filling  pro- 
cess. We  find  the  leaching  rate  uniform  over 
the  entire  charge,  notwithstanding  that  no 
mechanical  filling  device  is  used.  This  filling 
method  was  not  invented,  it  grew.  Elaborate 
filling  precautions  and  devices  found  necessary 


NOVEMBER,    1911 


369 


(with  slimy  sand)  to  prevent  the  slime  from 
choking  the  charge  wholly  or  in  part,  are  ab- 
solutely unnecessary  when  the  slime  is  re- 
moved before  filling  ;  the  Ovoca  classifier  does 
this  thoroughly,  so,  in  a  word,  our  practice  is 
to  sluice  the  ore  into  the  vats  and  sluice  it 
out  again  after  treatment.  Recently  some 
over-enthusiastic  advocates  of  the  all-sliming 
method  called  attention  to  the  expense  of 
handling  sand  as  compared  with  slime  ;  even 
this  argument  falls  to  the  ground,  when  sand- 
vats  are  filled  and  emptied  by  sluicing. 

The  slime  is  collected  and  agitated  in  steel 
vats  of  the  form  shown  in  Fig.  2.  Air  agita- 
tion is  used  after  the  method  illustrated.   The 


while  in  the  method  shown  in  Fig.  4  the  ex- 
panding air  is  dispersed  and  keeps  the  whole 
charge,  above  the  reverse  cone,  in  brisk  agita- 
tion, instead  of  that  small  portion  of  the  charge 
within  the  central  tube,  as  in  the  old  style  of 
pneumatic  agitator. 

The  slime  is  worked  in  charges  of  about  70 
tons,  agitated  in  cyanide  solution  of  varying 
strength,  and,  as  required,  given  a  final  treat- 
ment with  bromo-cyanogen. 

The  solutions  are  precipitated  on  zinc-shav- 
ing, the  dried  precipitate  being  ground  to  im- 
palpable powder  in  a  special  tube-mill  and 


Power-Shovel  Loading  -Iton  Car. 

discharge  from  the  central  air-lift  being  dis- 
persed, about  10  ft.  below  the  surface  of  the 
charge,  by  a  small  reverse  cone ;  in  this  way 
the  upper  portion  of  the  charge  is  kept  in 
brisk  agitation  by  a  surprisingly  small  amount 
of  air.  Sand,  if  present,  sinks  and  is  deflected 
toward  the  side  of  the  vat  by  the  lower  cone  ; 
rapidly  settling  to  the  suction  of  the  lift  it 
passes  up  again  and  in  this  way  is  kept  in 
active  agitation.  With  us  the  granular  por- 
tion of  the  slime  requires  all  the  agitation  we 
can  give  it.  Others  have  described  our  me- 
thod of  agitation  in  the  technical  Press,  but  I 
regret  to  say  have  drawn  largely  on  their 
imagination.  In  the  pneumatic  type  of  agita- 
tor where  the  air-lift  discharges  above  the  sur- 
face of  the  charge,  the  compressed  air  escapes 
into  the  atmosphere  before  it  is  fully  expanded, 


Breaker  Plant  durinfi  Constrmtion. 

sold  to  the  refineries.  At  first  we  had  much 
trouble  in  sampling  the  precipitate,  and  many 
disagreements  with  the  refineries  ;  since  it  has 
been  ground  to  powder,  howe\er,  we  have  had 
no  trouble  in  determining  the  value  of  the 
product. 

Cost  of  Millinc.  The  mill  reached  the 
10,000  tons  mark  in  March  1911,  and  averaged 
a  little  better  than  10,000  tons  per  month  for 
the  following  three  months,  closing  our  fiscal 
year.  I  take  the  expenses  for  these  montlis  in 
analysing  the  cost  : 

Month  Tons  Cost 

April 0,899  »11, 892-55 

Mav 10.277  12. 84091 

June 9,945  12.587-21 

30,121  137. 32067 

Average  :  '8ir239  per  ton. 


370 


THE    MINING    MAGAZINE 


The  mill  receives  one-tenth  of  its  supply 
from  a  small  breaker-plant  where  the  low- 
grade  mine-ore  is  crushed  to  about  i  in.  and 
conveyed  direct  to  the  Chilean  mills.  The 
dump-breaker  cost  is  based  on  the  ore  actu- 
ally mined  from  the  dump,  while  the  crushing 
and  concentrating  plant  treats  the  entire  ton- 
nage from  both  mine  and  dump,  less  the  waste 
picked  out.  Labour  includes  superintendents, 
and  all  salaried  men  employed  in  the  mill. 

Dump-Breaker. 

Per  ton  treated 

Power $1225  00  0  0436 

Operating  labour 1314  50       00468 

supplies...      13316       00048 

0-0516 

Repairs  labour 65994       00235 

■      „       supplies 125312       00446 

00681 

28.078  tons $4585-72  $01633 

Crushing  and  Concentrating, 

Power 1586275  $01946 

Operating,  labour 3238- 11       01075 

supplies...     35438       00117 

01192 

Repairs,  labour 244118       0  0810 

„       supplies 353036       01172 

01982 

Loading  concentrate.     289  41  00097 

30,121  tons...|15716-19  105217 

Cyaniding. 

Power $1459-00  $0  0484 

Operating,  labour 403983       01341 

supplies...  626403       0  2079 

0  3420 

Repairs,  labour 1010  40       0  0336 

„       supplies 642  05       0  0213 

0  0549 


30,121  tons...$13415-31 

Miscellaneous. 

Heating  $15143 

Water  service 14462 

Liability  insurance 169-21 

Fire  insurance 89840 

Taxes  140087 

30.121  tons...  $276453 

Recapitulation. 

Dump-breaker  $4585  72 

Crushing    and    con- 
centrating      571619 

Cyaniding 13415  31 

Miscellaneous 2764  53 

Mine-breaker 838  92 


30.121  tons...$37320-67 


$04453 


$0  0050 
0  0048 
00057 
0  0298 
0  0465 

$00918 


fO  1633 

05217 
0  4453 
0-0918 
0  0169 

Jl-2390 


1907  estimate  Actual  cost 

Power  $0-30  $02943 

Breaking,  sorting, 
fine-crushing,  con- 
centrating, and 

mine-breaker  038  (without      04560  (sorting 

sorting)  included) 

Cyaniding  0  47  03969 

M'lscellansous 009  0  0918 

Total  milling  cost... .$124  $12390 
Mining    and    dump- 
loading 010  00891 

Total     mining     and 

milling  cost $1  34  Estimated  $13281  Actual 

The  original  estimate  contained  an  item  of 
18  cents  per  ton  milled,  for  treating  the  con- 
centrate on  the  ground,  making  the  total  cost 
$1*52  per  ton.  This  estimate  covered  every- 
thing. The  two  cents  caused  some  amuse- 
ment, as  few  believed  it  possible  to  figure 
such  a  process  within  25  cents  per  ton  ;  while 
many  were  unkind  enough  to  say  it  would 
never  be  done  under  $4  per  ton.  The  figures, 
however,  speak  for  themselves. 

The  concentrate  was  not  worked-up  on  the 
premises,  as  better  arrangements  were  made 
with  the  smelters,  so  this  part  of  the  estimate 
cuts  no  figure,  inasmuch  as  the  cost  is  lower 
than  my  estimate  of  1907.  The  concentrate 
varies  from  4  to  7  oz.  gold  per  ton,  and  aver- 
ages nearly  5  oz.  It  contains  about  30%  iron 
excess  over  silica,  and  is  otherwise  an  excel- 
lent and  desirable  smelting  product,  since  it 
forms  the  ideal  binder  required  in  the  Hunt- 
ington -  Heberlein  or  pot  -  roasting  process. 
Hand-sorting  was  not  included  in  my  original 
estimate,  nor  -was  the  extra  cost  of  operating 
a  breaker  at  the  mine,  partly  to  supply  the 
fine-crushing  and  concentrating  plant.  These 
items  increase  the  cost  by  5  c.  per  ton  ;  de- 
ducting this,  the  breaking,  crushing,  and  con- 
centrating cost  becomes  40  c.  as  against  an  es- 
timated 38c.  Cyaniding  is  7i  c.  below  the  esti- 
mate, due  to  improvements  in  agitating,  in  the 
general  mechanism,  and  to  cheaper  chemicals 
than  were  available  four  years  ago. 

Extraction.  —  During  the  fiscal  year 
ended  June  30,   1911,  the  mill  treated 

Tons  Oz.  Oz. 

102,364  of  dump  ore  assaying  0152       15,56491 
7,436  of  mine     .,  ,,  0  231         1,72405 


We  are  now  in  position  to  compare  the 
original  estimate  made  in  March  1907,  based 
on  milling  10,000  tons  per  month,  with  the 
average  actual  cost  per  ton  milled,  in  April, 
May,  and  June  1911. 


109,800  tons  averaging  0157       17,288-96 

Oz.  % 

The  concentrate  contained 7546  80         43  65 

The  bullion  481480         27  85 

Total  recovery 12361-60         7150 

From  the  foregoing  results  it  is  apparent 
that  the  estimates  of  working  cost  and  extrac- 
tion have  been  translated  into  fact. 


PROGRESS  AT   PORCUPINE 


By  H.  H.  JOHNSON. 


THE  Porcupine  goldfield,  in  Ontario, 
Canada,  is  readily  reached  today  by 
the  new  railway,  which  was  opened  for 
traffic  as  far  as  Golden  City  some  three 
months  ago. 

In  common  with  almost  everything  else  in 
the  district,  Golden  City  was  nearly  wiped 
out  by  the  recent  disastrous  fire,  but  with  the 
advent  of  the  railway  it  has  been  rebuilt  with 
wonderful  rapidity.  Lying  at  the  north  end 
of  Porcupine  lake,  it  is  more  remote  from  the 
mines  so  far  discovered  than  its  sister  city, 
South  Porcupine,  which  is  connected  with  it 
by  a  good  service  of  motor-boats  that  make 
the  single  journey  in  from  10  to  15  minutes. 
The  railway  also  connects  the  two  centres, 
but  the  stations  are  situated  too  far  from  the 
main  thoroughfares  to  render  this  means  of 
transport  of  much  account,  especially  while 
there  is  at  present  only  one  train  a  day  in 
each  direction. 

From  South  Porcupine  the  railway  is  being 
rapidly  extended,  both  to  the  Dome  mine  to 
which  freight  is  already  being  conveyed,  and 
to  the  Hollinger  group,  which  begin  traffic  in 
December. 

The  few  roads  in  existence  are  mainly  com- 
posed of  6  to  8  in.  corduroy,  laid  on  the  mossy 
swamp  ;  in  summer,  even  to  a  poor  walker  pe- 
destrianism  is  as  agreeable  as  driving  over  such 
roads,  but  in  winter,  when  they  are  covered  in 
snow,  the  roads  are  said  to  be  excellent  for 
sleighing. 

Of  the  immense  number  of  claims  staked 
serious  work  has  so  far  been  undertaken  on 
comparatively  few  ;  the  majority  of  claim- 
holders,  having  'recorded'  sufficient  work  to 
protect  their  titles,  are  apparently  waiting  for 
some  more  capitalists  to  come  and  relieve  them 
of  their  properties  at  a  handsome  figure.  It 
is  significant  that,  although  the  camp  has  been 
visited  by  many  leading  engineers,  few  proper- 
ties have  changed  hands,  with  the  notable  ex- 
ception of  those  properties  acquired  by  Bewick, 
Moreing  &  Co. 

No  doubt  the  check  to  the  district  caused 
by  the  fire  in  June  has  been  accentuated  by 
the  small  amount  of  work  to  be  seen,  and  the 
extravagant  prices  asked  for  absolutely  un- 
developed claims  ;  but  there  can  equally  be 
no  doubt  that  when  a  regular  output  has  been 
established,  as  it  shortly   will   be,  and  when 


more  inclination  is  shown  to  do  genuine  work 
in  prospecting  and  development,  the  district 
will  take  a  place  in  the  ranks  of  recognized 
goldfields. 

At  the  Dome  mine,  work  on  the  surface  is 
going  on  apace,  getting  necessary  buildings 
ready  for  the  winter,  and  erecting  the  reduc- 
tion plant,  all  being  of  a  permanent  and  solid 
nature.  Further  work  has  recently  disclosed 
more  showings  of  a  similar  nature  to  the  so- 
called  Golden  Sidewalk,  which  is  certainly  a 
marvellous  spectacular  display.  The  company 
now  keeps  a  watchman  to  show  visitors  some 


A  sign  of  progress. 

of  the  rich  outcrop,  and  to  protect  the  latter 
from  the  '  high-grading  '  propensities  of  speci- 
men-seekers. The  40-stamp  plant  is  said  to 
be  going  to  start  up  in  January,  but  from 
present  appearances  it  is  evident  that  it  will 
require  much  strenuous  work  to  get  ready  by 
that  date. 

From  the  point  of  view  of  the  district  at 
large,  it  is  unfortunate  that  the  courteous 
management  is  unable  to  make  a  definite 
statement  as  to  their  development  assays,  or 
allow  visitors  below  ground.  Of  course,  the 
company  knows  its  own  business  best,  and 
has  a  perfect  right  to  please  itself  in  this  re- 
spect ;  but  it  would  dispel  a  good  deal  of  doubt 
and  suspicion  if  it  adopted  a  more  open  policy. 

On  the  Dome  Extension,  there  are  a  num- 
ber of  fine  surface  showings  in  a  stock-work 
of  veins,  and  exploration  underground  is  being 


371 


372 


THE    MINING    MAGAZINE 


energetically  undertaken  now  that  the  new 
compressor  plant  and  hoist  are  available. 
Capt.  H.  C.  Anchor,  an  old  and  experienced 
miner,  is  in  charge,  and  this  is  evidenced  by 
the  practical  way  in  which  the  work  is  being 
done  on  the  property. 

The  North  Dome,  with  its  rich  outcrops,  is 
both  drilling  and  shaft-sinking,  but  surface 
water  was  troublesome,  as  it  is  with  so  many 
Porcupme  properties.  A  new  force  of  men  is 
re-starting  work  on  the  Dome  Lake  claims, 
which  are  readily  approached  now  through 
the  West  Dome.  At  the  latter  everything  is 
in  good  shape  for  winter,  and  a  great  deal  of 
preliminary  surface  work  and  shot-drilling  has 
been  done,  but  at  the  time  of  my  visit  most  of 
the  ore  had  not  been  sampled. 

A  shaft  is  m  course  of  being  sunk  on  a 
likely  looking  vein  on  the  adjoining  Apex 
claim,  which  is  in  charge  of  Mr.  Anderson. 
On  this  property  a  core-drill  is  also  at  work, 
and  good  winter  quarters  are  now  completed. 
Here  also  water  is  causing  some  trouble. 

The  most  noteworthy  and  certainly  the  most 
systematically  worked  mine  that  I  visited  is 
the  Hollinger  ;  here  the  surface  has  been 
thoroughly  explored,  and  the  veins  to  the 
number  of  ten  stripped  and  carefully  sampled. 
The  main  vein  has  been  proved  for  over  IICO 
ft.  on  the  strike  at  the  100-ft.  level,  and  driv- 
ing on  the  same  vein  is  proceeding  from  the 
bottom  of  a  winze  on  the  200-ft.  level.  The 
new  main  shaft  has  been  holed  through  from 
the  first  level  to  the  surface;  rising  has  started 
from  the  second  level,  and  the  double-drum 
electric  hoist,  for  operating  the  shaft,  is  in 
place,  together  with  the  electric-driven  com- 
pressor. Good  progress  is  being  made  with 
the  foundations  for  the  new  40-stamp  mill, 
which  it  is  hoped  to  start  in  May.  The  rail- 
way will  terminate  in  the  Hollinger  township 
west  of  Miller  lake  on  the  property,  and  should 
be  handling  traffic  early  in  December,  as 
already  stated.  The  general  management  is 
in  the  capable  hands  of  P.  A.  Robbins,  who 
has  had  large  experience  in  South  Africa, 
Cobalt,  and  elsewhere,  and  he  is  ably  seconded 
by  W.  Globe,  the  assistant  manager. 

The  underground  workings  afford  the  best 
insight  into  the  character  of  the  Porcupine 
veins  so  far  discovered ;  it  is  evident  that 
their  lenticular  nature,  as  exposed  on  the  sur- 
face, is  a  regular  feature,  and  they  frequently 
develop  that  stringy  appearance  so  common 
in  quartz  veins  when  traversing  a  schist  for- 
mation. The  enclosing  schist  is  also  said  to 
carry  gold,  but  it  appears  certain  that  it  is 
pay-ore  only  w^hen  minute  quartz  stringers  are 


foliated  with  the  schist,  as  frequently  happens. 
So  far  water  is  not  proving  a  difficulty,  and 
this  bears  out  the  opinion  generally  held,  that 
although  the  district  is  swampy  and  contains 
many  lakes  and  rivers,  mining  is  not  likely  to 
be  hindered,  if  the  surface  water  is  handled 
properly. 

In  the  neighbourhood  of  the  Hollinger  are 
several  properties  of  considerable  promise,  on 
which  systematic  work  is  being  done  with 
varying  degrees  of  success.  Among  the  prin- 
cipal of  these  is  the  Mclntyre,  which  owns 
the  ground  adjoining  the  west  end  of  Pearl 
lake,  together  with  nearly  the  whole  of  the 
lake  itself.  This  property  has  earned  distinc- 
tion from  the  phenomenally  rich  outcrop  found 
on  its  southern  border.  In  addition  to  several 
core-drill  holes,  four  shafts  have  been  sunk  on 
various  veins  to  100  ft.,  and  a  fifth  shaft  has 
recently  been  started.  The  main  shaft,  No.  4, 
is  down  30  ft.  below  the  first  level  at  100  ft., 
and  progress  at  the  rate  of  25  ft.  per  week  is 
being  made  in  it,  as  well  as  in  the  southeastern 
shaft.  Nearly  150  ft.  of  driving  has  been  done 
in  the  vein  at  the  first  level  from  the  main 
shaft,  besides  cross-cutting,  and  the  vein  is 
looking  strong  and  carrying  good  ore,  though 
it  is  disturbed  in  the  eastern  face.  A  bore- 
hole put  down  near  the  centre  of  the  property 
penetrated  an  orebody  for  42  ft.  assaying  7h 
dwt.  per  ton.  So  far  it  does  not  appear  that 
this  vein  has  been  opened  up  in  any  other 
way,  most  of  the  work  being  confined  to  the 
veins  outcropping  either  on  the  southern  boun- 
dary or  north  of  the  lake  on  the  claim  adjoin- 
ing the  holding  of  the  Pearl  Lake  Gold  Mines. 
There  is  in  operation  a  12-drill  steam  and 
electric-driven  compressor,  which  has  enabled 
a  forward  development  policy  to  be  adopted, 
and  the  original  decision  to  erect  a  mill  im- 
mediately has  been  wisely  postponed  for  the 
time  being,  until  further  data  are  available  to 
enable  a  choice  of  the  size  of  plant  most  suit- 
able. 

On  the  Pearl  Lake  mine  a  great  deal  of 
useful  work  has  been  done.  The  position  of 
these  claims,  in  relation  to  the  Hollinger, 
makes  them  of  considerable  potential  value, 
but  it  seems  probable  that  in  depth  they  will 
also  catch  a  number  of  the  veins  of  the  Dixon, 
Mclntyre,  and  Jupiter  properties.  Indeed, 
this  has  to  some  extent  been  proved  by  bore- 
holes put  down  near  their  south  line,  for  these 
have  encountered  pay-ore  at  depths  ranging 
from  300  to  400  feet. 

On  the  opposite  side  of  the  lake  is  the 
Schumacher  block,  which  has  also  wonderfully 
rich  surface  showings.      It  is  said  that  the  as- 


NOVEMBER,    1911 


373 


says  are  so  high  that  they  are  "  frightened  to 
pubHsh  them  !  "  It  is  regrettable  that  so  little 
work  has  so  far  been  done  on  so  promising  a 
property.  Further  south  the  Vipond  is  doing 
good  work  in  shaft-sinking  and  driving  at  the 
100  ft.  level ;  in  the  cross-cut  at  that  level  the 
No.  3  vein  assays  8'6  dwt.  over  20  ft.  width. 

Up  till  now  the  township  of  Tisdale  has  fur- 
nished most  of  the  promising  properties  ;  gold 
has,  however,  been  found  over  a  wide  area  in 
small  quantities,  and  it  will  be  surprising  if 
further  prospecting  does  notreveal  moremines. 

The  Sandy  Falls  power  scheme  is  practi- 
cally completed  with  the  exception  of  string- 
ing the  wires  on  the  poles,  and  this  will  prove 


far  as  possible  throughout.  There  is  a  pro- 
nounced similarity  between  Porcupine  and 
Rhodesia,  and  it  appears  probable  that  though 
the  former  may  produce  big  mines,  it  is  more 
likely  to  be  a  country  of  comparatively  small 
mines,  like  the  latter. 

There  is  an  idea  prevailing  that  those  pro- 
perties lying  to  the  northeast  and  southwest 
of  the  principal  mines  are  certain  to  contain 
the  veins  of  the  latter  and  hence  are  the  most 
valuable  areas  in  the  district.  Too  much 
weight  should  not  be  attached  to  this  theory, 
for  in  the  first  place  although  many  veins  do 
strike  more  or  less  as  indicated,  this  is  by  no 
means  universally  the  case,  and  secondly  there 


THE    DOME    EXTENSION    AFTER    THE    FIRE. 


a  great  boon,  though  the  price  it  is  proposed 
to  charge,  namely,  £  10  per  kilowatt  per  an- 
num, based  on  a  three  minutes  peak  load, 
seems  capable  of  adjustment. 

In  the  course  of  a  visit  of  only  a  month's 
duration,  it  was  manifestly  unpossible  to  see 
more  than  a  few  of  the  more  important  pro- 
perties, from  which,  however,  the  impression 
is  gained  that  in  some  instances  work  has  been 
carried  on  under  almost  insuperable  difficulties 
prior  to  the  introduction  of  the  railway  ;  but  it 
seems  that  in  the  past  much  too  much  money 
has  been  spent  in  drilling,  and  too  much  im- 
portance given  to  the  results  so  obtained.  The 
veins  are  highly  lenticular,  both  in  strike  and 
dip,  and  the  only  convincing  manner  of  pro- 
specting must  be  to  find  the  orebodies  at  the 
surface  and  sink  on  them  and  stick  to  them  as 


is  no  proved  reason  why  profitable  veins  should 
not  be  found  anywhere  in  the  large  tract  of 
schist  country. 

The  facilities  for  working  are  distinctly 
favourable,  water  is  abundant,  medium  mine 
timber  fairly  plentiful,  while  coal  and  other 
supplies  can  be  landed  in  the  midst  of  the 
district  at  quite  reasonable  prices.  Labour 
is  also  being  attracted  at  rates  that  compare 
favourably  with  those  existing  in  the  W  est- 
ern  States  mining  camps. 

The  over-capitalization  of  so  many  of  the 
claims,  on  the  American  principle  of  millions 
of  dollars  in  paper,  is  unlikely  to  commend  it- 
self to  the  intelligent  European  investor,  and 
it  will  be  a  pity  if  initial  errors  of  this  nature 
are  allowed  to  cripple  a  mining  district  of  dis- 
tinct promise. 


RECENT  PROGRESS  ON  THE  KLONDYKE 


By   F.   L.   MORRIS. 


PRACTICALLY  the  whole  of  the  mining 
district  of  the  Klondyke  is  at  present 
either  owned  outright  or  held  under 
option  by  one  of  the  following  companies : 
Yukon  Gold  Co.,  the  Granville  Mining  Co., 
or  the  Boyle  Concession.  Each  of  these 
companies  has  expended  large  amounts  of 
money  in  the  development  work  on  a  big 
scale,  and  each  has  been  successful  in  accom- 
plishing results  that  at  one  time  seemed  un- 
likely in  a  country  so  far  on  the  Arctic  fron- 
tier. 

The  largest  and  most  completely  equipped 
of  the  companies  is  the  Yukon  Gold.  This 
company  has  in  operation  one  of  the  most 
successful  and  largest  ditch  and  hydraulic 
mining  systems  in  the  world.  The  total 
length  of  the  ditch  system  is  over  60  miles. 


loo  Ci/B 


.^rfP 


Cross-section  of  the  Yukon  Ditch. 


The  inverted  syphon  of  this  system,  which 
crosses  the  Klondyke  valley,  carries  approxi- 
mately 5000  miner's  inches  (125  sec.  ft.)  for 
two  miles  under  a  pressure  of  450  lb.  per  sq. 
inch. 

This  system  has  been  in  operation  for  three 
years.  During  the  past  summer  it  has  given 
but  very  little  trouble.  The  force  of  men 
employed  on  repairs  and  patrol  has  been  re- 
duced to  approximately  the  number  that 
would  have  been  necessary  had  the  same 
system  been  installed  for  the  same  length  of 
time  in  California.  The  effects  of  the  use  of 
this  water-supply  has  begun  to  show  itself 
by  the  large  pits  excavated  in  the  hillsides 
through  which  passes  the  White  Channel  of 
Bonanza  creek. 

The  most  noteworthy  point  in  regard  to 
this  ditch-system  and  its  operation  is  the 
high  duty  attained  in  washing  the  gravel  ; 
this  amounts  to  5  cu.  yd.  per  miner's  inch 
in  24  hours.  The  average  duty  per  inch  in 
all  of  the  hydraulic  mining  in   California  will 


not  be  far  from  2  cu.  yd.  per  miner's  inch. 
This  point,  next  to  the  gold-content  of  the 
ground,  is  the  most  important  to  the  operator. 
The  Yukon  Gold  company  has  9  gold 
dredges  in  operation.  Two  of  these  machines 
were  constructed  during  the  past  season. 
They  have  steel  hulls  and  a  bucket  capacity 
of  seven  cubic  feet.  It  may  be  added  that 
they  are  the  only  dredges  with  steel  hulls  in 
operation  at  present  on  the  North  American 
continent.  The  general  design  is  the  same 
as  the  wooden  hull.  The  machinery  is  iden- 
tical. The  cost  of  installation  is  but  little 
more  and  the  general  operation  is  expected 
to  be  more  satisfactory. 

In  addition  to  the  innovation  of  the  ^teel- 
huU  dredge,  this  company  has  accomplished 
what  would  at  first  seem  to  be  impossible  in 
the  way  of  handling  heavy  '  block  '  bedrock. 
Two  of  their  dredges  are  working  in  the  most 
difficult  hard  bedrock  found  in  the  Yukon, 
and  are  handling  it  successfully  to  a  depth  of 
eight  feet  in  some  places. 

The  tailing-piles  left  by  these  dredges  could 
be  likened  to  a  waste- dump  from  a  quartz 
mine  as  to  appearance,  which  they  more  re- 
semble than  the  ordinary  dump  made  by  a 
dredge  digging  alluvial  gravel.  However,  it 
must  not  be  taken  for  granted  that  a  machine 
built  on  the  same  design  as  the  Yukon  dred- 
ges could  dig  into  and  handle  as  hard  a  schist 
as  would  be  found  in  other  parts  of  the  world, 
because  the  only  reason  that  it  has  been  pos- 
sible in  this  instance  is  that  the  gravel  and 
the  bedrock  have  been  frozen,  thereby  wedg- 
ing the  particles  apart  by  the  expansion  of 
the  ice  in  the  rock  crevices. 

Probably  80%  of  the  ground  dredged  by 
this  company  is  solidly  and  permanently 
frozen.  This  ice  is  removed  by  steam-thaw- 
ing. There  has  been  little  change  in  the  sys- 
tem of  thawing  during  the  past  year.  This 
part  of  the  work  has  received  a  great  deal  of 
attention  of  late  and  the  cost  will  no  doubt 
be  reduced  slightly  next  season.  At  present, 
the  cost  of  thawing  is  over  one-half  the  total 
cost  of  working  the  ground. 

The  Boyle  Concession  Co.  is  operating  two 
dredges,  both  designed  and  erected  by  the 
Marion  Steam-shovel  Co.  Their  property 
lies  in  the  valley  of  the  Klondyke  river,  the 
bed  of  which  is  partly  thawed.     Their  dredges 


374 


NOVEMBER,    1911 


375 


to  date  have  been  working  on  ground  that 
was  naturally  thawed,  thus  reducing  the  work- 
ing cost  to  a  much  lower  figure  than  that  of 
the  Yukon  Gold,  which  is  compelled  to  incur 
the  immense  cost  of  artificial  thawing. 

Among  the  noteworthy  results  accomplished 
by  this  company  is  the  erection  of  a  16  cu.  ft. 
dredge  on  their  property  in  the  summer  of 
1910.  This  dredge  was  the  first  of  this  large 
capacity  ever  built  anywhere.  It  was  thought 
by  many  of  the  best  dredge-operators  of  the 


The  Granville  Mining  Co.  represents  the 
properties  consolidated  by  A.  N.  C.  Tread- 
gold.  This  company  as  yet  has  not  begun 
mining  operations.  The  holdings  are  chiefly 
composed  of  claims  on  the  Dominion  creek 
side  of  the  divide,  while  those  of  the  Yukon 
Gold  and  the  Boyle  companies  are  on  the 
Klondyke  slope  of  the  divide. 

The  chief  work  accomplished  by  this  com- 
pany since  its  organization  is  the  erection  of 
a  large  power-plant  to  be  used  in  conjunction 


LAYING    WOODEN-STAVE    PIPE    FOR    THE    YUKON    GOLD    CO.'S    WATER    SYSTEM. 


United  States  that  it  was  a  mistake  to  build 
so  large  a  machine  as  this  in  a  country  so 
inaccessible  as  the  Yukon  for  the  reason  that 
the  breaking  of  one  important  weak  part 
would  mean  the  loss  of  the  whole  of  a  season's 
operations.  Nevertheless  the  machine  in 
question  has  been  run  successfully  for  part  of 
1910  and  the  whole  of  the  season  of  1911 
without  a  serious  breakdown,  and  it  can  be 
said  after  this  test  that  the  machine  is  suc- 
cessful. Its  capacity  is  as  large  as  if  it  had 
been  working  in  the  mild  climate  of  Califor- 
nia, namely,  a  maximum  of  13,000  cu.  yd.  per 
day  for  a  whole  week. 

5—5 


with  the  mining  operations,  and  also  as  a 
commercial  plant  furnishing  power  to  other 
local  mining  companies.  This  plant  has  a 
capacity  of  10,000  kw.,  in  two  units,  both  of 
which  are  in  place  and  ready  for  operation 
when  desired.  At  present  it  is  supplying  all 
the  motive-power  for  the  Yukon  territory.  It 
is  assumed  that  this  company  will  undertake 
to  mine  its  properties  on  lines  different  from 
those  at  present  in  vogue  locally.  It  is  to  be 
hoped  that  these  will  be  as  successful  as  the 
installation  of  the  power-plant.  The  control  is 
in  the  hands  of  experienced  men  including 
H.  C.  Hoover,  A.  C.  Beatty,  and  H.  H.Webb. 


MINING  METHODS  AT  BRADEN,  CHILE 


By  FRANK  LANGFORD. 


THE  mining  of  ore  has  been  less  discussed 
in  detail  than  ore  reductioa  ;  this  will  be 
a  sufficient  apology  for  the  accompanying 
outline  of  a  system  in  deep  mining  that  will 
rival,  in  low  cost,  the  use  of  the  steam-shovel 
in  surface  operations. 

It  is  a  modification  of  the  plan  first  put  into 
practice  at  the  Melones  gold  mine  in  California 
in  1900  and  elsewhere  since  then  by  myself, 
with  the  aid  and  advice  of  such  eminent  con- 


which  had  been  drawn,  or  might  be  full  of 
broken  ore,  putting  400  or  600  feet  of  ore  on 
the  chutes  below  ;  the  fear  that  if  the  ore  were 
soft  and  fractured  the  backs  could  not  be  sup- 
ported or  made  safe  on  the  moving  fill,  upon 
which  the  machinery  had  to  be  set  and  opera- 
ted ;  the  fear  that  if  the  rock  were  hard  enough 
and  tough  enough  to  stand  in  large  open  backs 
it  would  not  break  fine  enough  to  pass  through 
the  chutes  ;  and  so  forth. 


CROSS-CUT 

DIAORAM  ILLUSTRATING  METHOD  OF  MINING. 


suiting  engineers  as  Messrs.  W.  B.  Devereux, 
William  Braden,  and  Pope  Yeatman.  In  its 
simplest  adaptation  the  method  consists  in 
driving  a  drift  under  the  first  level  on  the  ore- 
body  to  be  mined,  raising  chutes,  manways  and 
passes  at  an  angle  with  the  vertical  of  45°,  the 
stope  being  simply  raised  from  the  loading 
chutes  along  the  level  and  tilled  with  broken 
ore,  the  surplus  being  drawn  out  through  the 
chutes  without  sub-level,  grizzlies,  or  other 
detail ;  likewise  the  filling  when  the  stope  is 
completed.  Many  difficulties  were  anticipated, 
such  as  the  weight  of  two  or  three  hundred  feet 
of  broken  ore  on  the  loading  chutes  ;  blocking 
of  the  chutes  with  coarse  ore  ;  dangers  in  ex- 
tending the  stopes  overhead  to  the  next  level, 


The  actual  result  was  that  more  than  a  mil- 
lion tons  of  ore  was  mined  with  a  record  of 
only  one  man  killed  by  a  fall  of  rock  in  the 
stopes,  one  by  falling  down  a  main  shaft,  and 
one  by  contact  with  a  440-volt  electric  current. 
Moreover,  the  ore  was  got  for  half  the  cost, 
and  the  rate  of  pay  of  labour  was  10%  higher. 

Referring  now  to  the  accompanying  sketch. 
It  is  an  outline  of  my  general  plan  of  mining 
the  more  regular  and  deeper  orebodies  of,  in 
this  case,  the  Braden  Copper  mines  of  Chile. 
These  consisted  of  fractured  material  with  a 
good  tough  hanging  wall-rock  and  a  foot-wall 
country  carrying  considerable  copper  but  not 
definable,  except  by  sampling  and  assay.  The 
workings  consist  of : 


376 


NOVEMBER,    1911 


377 


1.  Drifts  near  the  hanging  and  foot-wall, 
respectively,  and  a  cross-cut. 

2.  Rise  45°  on  centre  of  orebody  to  the  level 
above. 

3.  Cross-cut  from  this  rise,  to  hanging  and 
foot,  at  distances  of  15  metres  alternately  to 
prospect  the  orebody,  define  its  limits,  and 
furnish  easy  access  to  the  stopes  continuously, 
as  they  are  enlarged  and  filled. 

4.  Rise  loading-chutes  to  3  metres  above  the 
drifts  at  intervals  of  9  metres. 

5.  A  shelf  or  loading  ledge  cut  at  6  metres 
over  the  main  level  behind  the  loading-chutes 
to  facilitate  the  blasting  of  boulders  in  the 
chutes,  and  as  part  of  the  final  under-cut  in 
narrower  orebodies. 

In  the  wider  orebodies  proceed  as  outlined 


of  the  mine,  if  desired  ;  the  purpose  here  being, 
not  to  show  what  might  be  done,  but  to  show 
the  least  work  that  will  win  the  ore  safely, 
surely,  rapidly,  and  at  the  lowest  cost.  While 
it  may  be  said  at  first  glance  that  special  con- 
ditions are  essential  to  the  employment  of  this 
system,  it  will  be  seen  by  a  little  study  that  it 
may  be  employed  in  many  mines  of  modern 
type,  always  with  modifications  to  meet  local 
conditions,  a  precaution  that  is  much  adver- 
tisedin  connection  with  milling  and  metallurgy, 
while  in  mining  it  is  often  left  to  chance  or  to 
a  trail  blazed  by  underground  prospecting. 

As  an  illustration  of  the  flexibility  and  of  the 
modifications  suggested  or  dictated  by  varying 
conditions,  I  would  site  the  practice  in  three 
places. 


CR0S5-CU1 

CONTINUATION  FROM  OPPOSITE  PAGE. 


above  and  in  addition  drive  a  central  drift,  or 
rise  from  the  cross-cuts  on  the  level  to  about 
9  metres  above  the  main  le\  el  and  there  under- 
cut the  central  rib  in  pillars  preferably  on  a 
level  plane,  as  shown.  Extend  the  hanging- 
wall  stope,  the  foot-wall  stope,  and  the  cross- 
connecting  stopessimultaneously.  When  com- 
pleted to  the  level  above,  which  has  been 
worked  out,  and  while  the  stopes  are  full  of 
ore,  shoot  the  pillars  slowly  from  one  end  of 
the  orebody,  permitting  the  central  rib  to  settle 
slowly,  thereby  crushing  the  rock  fine  enough. 
In  the  case  of  a  free  and  well  defined  hanging- 
wall  slip,  the  hanging  stope  may  not  even  be 
necessary.  Main  supporting  pillars  and  man- 
ways  may  be  left  in  the  lower  grade  sections 


First.  At  Melones,  in  California,  each  ore- 
shoot  was  mined  in  one  long- wall  stope  of  any 
length  and  of  widths  up  to  75  feet  without 
under-cut  or  caving  and  without  sub-levels  or 
milling  the  ore  through  grizzlies  underground. 

Second.  At  the  Fortuna  No.  2  mine,  in 
Arizona,  where  for  many  reasons,  such  as  the 
unknown  width  of  the  orebody,  the  fractured 
nature  of  the  ore-bearing  rock,  the  commercial 
requirements,  etc.,  the  stopes  were  laid  across 
the  orebody  in  room-and-pillar  form. 

Third.  In  the  deeper  Braden  orebodies,  in 
Chile,  where  the  system  has  been  amplified 
and  modified  as  shown  in  my  sketch  herewith 
to  meet  the  requirements  of  preparing  large 
areas  of  stopes,  to  facilitate  the  economic  min- 


378 


THE    MINING    MAGAZINE 


ing  of  more  than  4000  tons  daily,  until  the 
drawing  of  corresponding  filling  and  pillars 
can  begin,  and  the  requirement  that  in  such 
preparation  of  large  stoping-areas  as  little  ore 
as  possible  be  mined,  on  account  of  the  lack  of 
mill-capacity  and  power  until  such  time  as  the 
new  12,000  hp.  plant  and  the  2000  ton  concen- 
trator were  ready. 

The  points  aimed  at  are  : 

1.  To  develop  the  most  ore  with  the  least 
work. 

2.  To  make  the  prospecting  and  the  develop- 
ment work  serve  best  for  mining  and  drawing 
the  ore. 

3.  To  allow  the  greater  amount  of  ore  to 
mine  itself. 

4.  To  avoid  the  use  of  timber. 

5.  To  permit  the  drawing  of  stopes  evenly 
over  large  areas,  a  desirable  precaution  in  pre- 
venting the  mixture  of  waste  from  the  walls 
with  the  ore  ;  although  this  is  an  evil  too  much 
feared  in  many  cases  of  tough  hanging  and  of 
country  carrying  some  ore. 

6.  To  facilitate  the  drawing  of  a  large  part 
of  the  ore  direct  from  the  stopes  to  the  lower 
haulage-levels  by  branch  rises  from  the  main 
ore-passes  leading  down  1000  ft.  to  the  main 
haulage  or  mill-level,  such  main  ore-passes 
being  also  on  inclines  of  45°  to  55°. 

7.  To  cause  the  ore  to  crush  itself  in  caving 
fine  enough  to  be  handled  at  the  chutes. 

8.  To  permit  easy  access  of  the  miners  to 
the  stopes  and  without  hoisting. 

9.  To  provide  good  ventilation  in  the  stopes. 

10.  To  facilitate  supervision. 

At  the  Melones  air-drills  of  the  largest  sizes 
were  used. 

At  the  Fortuna  smaller  or  f  in,  piston  drills 
were  used. 

At  the  Braden  the  air-feed  hammer-drills 
are  used. 

The  length  of  hole  usually  drilled  per  shift 
with  each  machine  in  place  was  60  ft.  for  the 
big  machine,  45  ft.  for  the  smaller  piston-drill, 
and  100  ft. for  the  hammer-drill.  Theefficiency 
must  not,  however,  be  measured  by  the  feet 
drilled.  The  comparison  is  given  more  to  show 
the  wide  range  of  machines  employed  in  the 
same  general  mining  plan  under  different  con- 
ditions. 

The  cost  of  this  system  may  be  indicated 
by  quoting  the  results  at  Melones  during  the 
year  October  1,  1908,to  October  1,  1909.  Dur- 
ing this  time  94,300  tons  was  raised  from  the 
stopes  and  12,800  tons  taken  from  the  surface; 
the  quantity  milled  was  123,200  tons.  The 
cost  of  mining,  including  development,  was 
$41,014  or  39  cents  per  ton,  and  the  total  cost 


$125,075  or  87  cents  per  ton.  During  one 
month  the  costs  were  as  low  as  32  cents  and 
79  cents  respectively.  These  are  low  figures  ; 
indeed,  they  are,  I  believe,  the  lowest  figures 
ever  reached  for  deep  hard-ore  mining,  milling, 
and  concentration  under  conditions  not  by  any 
means  ideal.  The  cost  for  milling,  amalga- 
mating, and  concentrating,  and  the  saving  at- 
tained on  ore  containing  much  of  the  value 
in  tellurium  and  requiring  fine  concentration 
should  make  the  '  porphyry  '  operators  put  in 
a  little  over-time  to  explain  their  triple  cost 
and  their  triple  losses.  At  the  Fortuna  the 
corresponding  cost  for  mining  was  46  c.  per 
ton.  At  the  Braden  not  enough  actual  slop- 
ing has  yet  been  done  to  fix  the  cost  of  mining, 
but  it  should  not  be  more  than  half  that  of  the 
Melones. 

The  introduction  of  this  plan  of  minmg  has 
met  with  considerable  opposition  in  each  case 
and  has  been  subjected  to  the  criticism  of  the 
Comstocker,  deprived  of  some  fancy  timber- 
framing  ;  of  the  sealed-bag  travelling  engineer, 
deprived  of  the  chance  of  applying  formulas 
for  estimating  ore  ;  and  of  auditors  who  would 
show  capital  '  locked-up  '  in  broken  ore,  when 
in  fact  the  ore  broke  itself. 

I  have  been  most  fortunate  in  having  splen- 
did assistants  from  time  to  time,  like  Mr. 
Locke,  Mr.  Kett,  Mr.  Williams,  and  others, 
with  open  minds,  experienced,  but  unmarried 
to  inherited  methods  of  mining  or  cost-book 
prices  of  milling. 

British  Coinage  during  1910. — The  re- 
port of  the  Mint  for  1910  just  published  shows 
that  the  output  of  gold  and  silver  coins  was 
the  largest  on  record.  There  has  lately  been 
a  rapid  increase  in  the  demand  for  gold  coin, 
and  the  value  of  those  produced  in  1910  was 
;^22,891,564,  as  compared  with  an  average  of 
122  millions  during  the  preceding  ten  years. 
The  following  table  gives  a  summary  for  1910  : 

Coin.  Number.  Value. 

Sovereigns 22,379,624  ;^22,379,624 

Half-sovereigns 5,023,881  2,511,940 

Half-crowns 2,557,685  319,710 

Florins 5,650,713  565,071 

Shillings 26,547,236  1,327,361 

Sixpences 12,490,724  312,268 

Fourpences(  Maundy)           2,755  45 

Threepences 4,564,820  57,060 

Twopences  (Maundy)           2,998  24 

Pence  (Maundy) 3,392  14 

Pence 29,549,184  123,121 

Halfpence  10,769,920  22,437 

Farthmgs 2,598,400  2,706 

Totals  122,141,332  i:27,621,387 


EARLY  DAYS  ON   THE   RAND 

By  D.  B.  SCHUITEMA. 


IN  June  1884,  I  travelled  with  the  Vice- 
President  of  the  Transvaal,  Cornelius 
Bodenstein,  from  Pretoria  to  Potchef- 
stroom.  We  left  Pretoria  about  7  o'clock  in 
the  morning  and  slept  that  night  at  the  Juks- 
key  River  hotel  kept  by  a  man  named  Edgson. 
Starting  the  following  morning  at  6  o'clock, 
we  came  about  half-past  seven  to  a  farm  which 
I  believe  now  was  Waterval,  which  adjoins 
Randfontein.  Mr.  Bodenstein  said  to  me  : 
"  Do  you  know  we  are  now  driving  over  a 
goldfield  ?  "  I  asked  the  old  man  :  "  What 
do  you  mean,  Oom  Cornelius  ?  "  "  Well, 
what  I  tell  you  ;  we  are  driving  over  one  of 
the  richest  goldfields  in  the  world."  As  I  was 
well  aware  that  the  Transvaal  Government 
was  then  hard-up  for  cash,  I  said  :  "  But  why 
does  the  Government  not  throw  the  ground 
open  as  a  public  digging,  or  work  it  them- 
selves ?  "  "  Well,  my  dear  Sir,"  the  old  man 
answered  me,  "  I  am  afraid  it  will  have  to  be 
done  some  time,  but  we  are  afraid  that  the 
English  will  then  take  our  country  again." 

This  was  shortly  after  the  first  Boer  war  of 
1881.  At  that  very  time  a  deputation  con- 
sisting of  President  Kruger,  General  Smit, 
and  the  Rev.  S.  J.  du  Toit,  then  Superinten- 
dent of  Education,  was  in  Europe  to  arrange 
for  the  alteration  of  the  Convention.  Many 
a  time  since  have  I  thought  of  the  old  man's 
words,  as  the  Witwatersrand  goldfield  was 
certainly  the  cause  of  the  second  Boer  war. 

Mr.  Bodenstein,  I  am  sure,  alluded  to  the 
discovery  of  alluvial  gold  and  also  of  gold  in 
quartz  veins  then  already  made  by  a  certain 
Minaar,  from  Potchefstroom,  who  with  the 
assistance  of  people  from  Pretoria  commenced 
working  the  farm  Kromdraai  on  the  Jukskey 
river,  north  of  what  is  now  Krugersdorp.  A 
German  named  Hammerschlag  had  also  found 
gold  on  a  farm  about  3  miles  farther,  north- 
west of  the  Crocodile  river.  At  this  place  the 
gold  was  in  a  large  white  quartz  outcrop,  and 
he  floated  a  company  in  Natal  in  1885. 

It  must  be  understood  that  none  of  these 
men  were  mining  experts  or  engineers,  for 
up  to  that  time  gold  had  been  found  only  at 
Pilgrim's  Rest  (Lydenburg)  and  what  is  now 
the  Barberton  district,  in  quartz  veins.  No- 
body searched  or  prospected  for  gold  in  any 
other  formation.  To  prove  that  even  as  late 
as  April  1886  it  was  not  generally  recognized 


that  gold  existed  in  the  banket  formation,  it  is 
known  to  me  that  the  same  Mr.  Hammerschlag 
had  a  contract  with  the  owner  of  the  eastern 
portion  of  Roodepoort,  on  which  are  now  the 
Durban  Roodepoort  and  United  Roodepoort 
mines,  to  prospect  for  gold,  with  an  option  to 
purchase.  He  abandoned  this  option  on  April 
1,  1886,  as  his  prospector  could  not  find  enough 
gold  in  the  white  quartz  leaders. 

It  was  about  the  commencement  of  the 
year  1885  that  another  Boer,  named  Laurenz 
Geldenhuis,  found  a  rich  deposit  in  the  hills 
to  the  north  of  the  farm  Roodepoort,  close  to 
the  Hospital  Hill  shales.  He  showed  his  find 
to  the  owner  of  the  farm — Harry  Struben — 
who  had  bought  the  land  from  him  for  agricul- 
tural purposes.  The  assay-value  of  the  piece 
of  ore  (a  mixture  of  shale  and  quartz)  taken 
from  the  surface  and  about  the  size  of  a  horse's 
head,  was  900  ounces  of  gold  and  300  ounces 
of  silver  per  ton.  Mr.  Struben,  who  was  at 
that  time  already  well  off  and  had  had  some 
experience  in  the  diamond  fields  and  at  Pil- 
grim's Rest,  erected  a  10-stamp  mill  in  the 
'  kloof  '  about  two  miles  north  of  the  present 
Main  Reef  series,  before  having  opened  up 
any  mine.  This  mine  proved  a  failure,  as  it 
was  only  a  blow,  but  all  the  same  this  dis- 
covery was  the  commencement  of  a  fortune 
for  Mr.  Struben,  as  he  secured  mining  leases 
on  farms  in  the  same  line  of  hills,  the  majority 
of  the  ground  lying  south  and  containing  what 
is  now  known  as  the  Main  Reef.  Among 
others  the  farm  Vogelstruisfontein  (now  Vogel- 
struis  Estates)  and  also  the  farm  Elandsfon- 
tein,  on  which  is  now  the  Geldenhuis  Estate, 
were  secured  by  him. 

In  December  1885  I  visited  his  mine  with 
my  brother-in-law  Dirk  van  Breda,  who  was 
a  gold-digger  from  Barberton.  The  Master 
of  the  High  Court  and  Orphan  Master,  Jan 
Joubert,  hearing  of  my  intended  visit,  asked 
me  to  see  about  a  farm  in  the  neighbourhood, 
that  is,  the  western  portion  of  Roodepoort. 
The  farm  was  mortgaged  at  the  Orphan  Cham- 
ber for  ;^500  and  he  wished  me  to  buy  it  for 
^700,  so  as  to  close  the  estate.  \\'e  looked 
from  the  top  of  the  hill  on  which  Struben's 
mine  was,  down  toward  Roodepoort,  but  never 
visited  the  farm,  as  it  was  rather  late.  On 
asking  my  brother-in-law  what  he  thought, 
whether  the  farm  had  any  chance  of  being 


379 


380 


THE    MINING    MAGAZINE 


gold-bearing,  his  reply  was  :  "  I  would  rather 
look  for  diamonds  than  for  gold  there  " — a 
characteristic  answer  from  a  man  who  had 
been  in  his  early  days  on  the  diamond  fields 
and  later  at  Pilgrim's  Rest  and  the  mountains 
of  Barberton.  I  only  mention  this  incident 
to  show  what  was  thought  to  be  the  real  value 
of  the  Rand  farms  at  the  end  of  1885.  This 
same  portion  of  Roodepoort  was  in  1886  sold 
for  ^10,000  and  the  buyer  floated  it  into  a 
company  known  as  the  Princess  Estate. 

About  March  1886  there  arrived  at  Pretoria 
a  Scotch  cart  drawn  by  four  miserable  don- 
keys ;  the  Stars  and  Stripes  were  flying  on 
one  side  and  the  Transvaal  flag  on  the  other. 
The  owner  of  this  cart  was  a  prospector  well 
known  at  Pilgrim's  Rest ;  it  was  Dick  Hart,  a 
real  old-fashioned  character  of  the  Bret  Harte 
digger  type,  always  with  his  little  stump  of  a 
pipe  in  his  mouth,  and  talking  with  a  Yankee 
twang  ;  ever  ready  to  take  a  drink,  or  to  stand 
one,  at  the  nearest  public-house,  which  in  this 
case  was  a  small  tavern  called  the  '  Hole-in- 
the-Wall.'  He  was  always  telling  a  yarn  or 
tale,  coming  back  in  a  mysterious  way  to  a 
marvellous  rich  discovery  he  had  just  made  of 
a  goldfield  at  least  30  miles  long  by  3  miles 
broad.  Old  Pretorians  will  remember  him 
standing  with  his  cart  in  the  market  square, 
the  cart  containing,  among  the  pots  and  pans 
and  his  bedding,  lots  of  bags  (from  the  size  of 
the  small  money-bags  of  the  Standard  Bank 
of  South  Africa  to  the  50-lb.  Natal  sugar  bags) 
filled  with  a  rock  in  which  no  one  had  ever 
seen  any  gold.  Old  Dick  panned  this  rock 
in  our  presence  at  the  water  furrow  running 
in  front  of  his  cart  in  the  market  square.  He 
showed  us  the  gold  in  the  dish  ;  he  showed  us 
the  results  of  his  pannings  in  little  bottles  ;  he 
showed  us  the  black  sand  with  the  fine  gold 
visible  between  the  sand  in  the  only  saucer  he 
possessed  ;  but  I  am  sure  most  of  us  looked 
on  him  as  a  cheat  or  a  conjuror. 

Hart  asked  from  the  Government  ;^1000 
sterling  for  showing  them  the  place  from  which 
he  had  obtained  his  ore. 

At  that  time  I  had  already  a  little  experi- 
ence in  gold-washing  through  my  visits  to 
the  Devils  Kantoor  and  the  Barberton  gold- 
fields,  where  my  brother- in-law  worked.  One 
of  my  friends,  a  Cape  Colony  Africander,  by 
name  of  Gert  du  Plessies,  who  had  been  with 
Dick  Hart  in  the  Lydenburg  district,  very 
soon  got  from  the  latter  an  inkling  as  to  the 
whereabouts  of  the  new  discovery,  and  he 
suggested  to  me  that  I  should  support  him 
with  wagons,  oxen,  tools,  and  provisions,  so 
that  he  might  find  out  by  prospecting  on  the 


Witwaters  Rand  where  this  wonderful  ore 
came  from.  As  I  did  not  much  believe  in 
the  business  and  partly  also  as  money  was 
rather  scarce,  I  could  not  act  on  his  sugges- 
tion, and  a  few  days  later  he  got  Japie  de 
Villiers,  a  rich  inhabitant  of  Pretoria  who  had 
been  in  his  early  days  in  Australia,  to  support 
him.  The  outcome  of  his  trip  was,  I  may 
here  mention,  that  he  got  hold  of  the  piece  of 
ground  now  belonging  to  the  Robinson  Gold 
Mining  Company.  He  had  secured  the  mine- 
ral rights  on  this  piece  of  land  for  20  years  at 
a  yearly  rental  of  ^100  from  the  owner,  Piet 
Bezuindenhout,  with  six  months  free  for  pros- 
pecting. When  his  prospecting  period  was 
nearly  finished,  he  sold  his  half-interest  to 
J.  B.  Robinson  for  /'1500  cash  and  3000 
shares  in  a  company  to  be  floated  with  a 
nominal  capital  of  not  more  than  ^'50,000. 
His  supporter,  Japie  de  Villiers,  sold  his  half- 
interest  a  few  months  later  for  ^15,000  cash. 
During  the  boom  time  of  1888-'89  the  com- 
pany was  reconstructed  with  a  capital  of 
;^2, 750,000,  the  original  holder  of  the  50,000 
shares  taking  for  each  one  pound  share  10 
shares  of  a  value  of  £b  each  and  setting  aside 
^250,000  for  working  capital. 

Dick  Hart  was  still  trying  to  get  /1 000 
from  the  Government  for  telling  them  where 
this  wonderful  goldfield  was,  but  even  before 
Gert  du  Plessies,  another  citizen  of  Potchef- 
stroom,  Mr.  Bantjes,  had  found  out  that  gold 
existed  in  the  banket,  as  the  rock  was  then 
called  by  the  Boers,  this  name  being  given  to 
it  by  them  because  of  the  pebbles  in  the  sand- 
stone reminding  them  of  the  almonds  and 
raisins  of  a  Dutch  cake  called  banket.' 
Bantjes  organized  a  small  syndicate  at  Pot- 
chefstroom  in  April  1886  and  secured  mining 
rights  on  the  western  portion  of  the  farm 
Paardekraal,  which  property  is  now  called 
the  Bantjes  Gold  Mining  Co.  He  showed 
his  discovery  to  Struben,  who,  as  mentioned 
before,  had  the  farm  Vogelstruisfontein  ad- 
joining Paardekraal.  Struben  commenced 
prospecting  there  and  the  sons  of  Laurenz 
Geldenhuis  started  prospecting  on  the  farm 
Elandsfontein,  now  the   Geldenhuis   Estate. 

In  the  meantime  a  rich  discovery  had  been 
made  at  Barberton,  namely,  the  Sheba,  which 
attracted  the  attention  of  the  financiers  of 
Kimberley.  They  sent  their  engineers  and 
agents  to  Barberton,  but  as  they  had  to  pass 
through  Potchefstroom  and  Pretoria,  where 
they  heard  of  the  new  discovery  on  the  Wit- 
watersrand,  many  of  them  turned  back  from 
Barberton  to  the  goldfield  that  eventually 
proved  to  be  the  greatest  of  all. 


NOVEMBER,    1911 


381 


DISCUSSION 


Our  readers  are  invited  to  criticize  anything  appearing  in  this 
magazine  and  to  discuss  other  subjects  of  general  technical 
interest. 

A  Miner's  Protest. 

The  Editor : 

Sir — "  This  magazine  is  tied  by  no  strings 
save  the  cord  of  sympathy  with  all  those  that 
go  down  the  mine  in  skips."  The  above,  and 
the  statement  of  Mr.  Hays  Hammond  to  in- 
vestors, talking  of  the  shyster  mining  engineer 
and  the  unscrupulous  promoter  :  "  blame  not 
the  honest  miner,  whom  I  have  met  in  the 
tundras  of  Alaska,  fever-stricken  plains  of 
death  valley,  and  found  him  confident,  upright, 
brave,  and  a  man  of  generous  impulse  " — I  am 
quoting  from  memory — encourage  me  to  ad- 
dress you  on  behalf  of  my  fellow  Rand  miners. 

Even  in  your  journal  some  few  quondam 
Rand  managers — I  marvel  why  their  houses 
did  not  retain  them — frequently  proclaim  aloud 
the  inefficiency  of  the  white  miner.  The  Press 
at  this  end  is  subsidized.  Journalism  as  a  noble 
calling  does  not  exist.  An  editor  is  wrung-up 
by  one  of  the  houses,  his  leaders  are  inspired, 
his  tone  is  coloured,  his  policy  is  shaded  by  his 
patron. 

To  return  :  It  is  against  logic  and  the  weight 
of  evidence  to  assert  that  the  Rand  miner  is 
inefficient.  The  little  that  some  of  our  critics 
do  know  concerning  the  breaking  of  ground 
they  were  content  to  acquire  from  some  of  us. 
No  miner  however  goodnatured  gives  his  last 
saving  item  of  experience  to  the  casual  learner 
whose  loyalty  he  distrusts.  That  same  know- 
ledge given  may  be  used  against  him  in  time  of 
strike.  The  miner  must  conserve.  His  pro- 
fession is  occult.  He  is  dealing  with  forces 
or  factors  that  cannot  be  determined  by  mathe- 
matical precision.  The  exploding  force  of 
powder  and  the  breaking  strain  of  a  rock  can- 
not be  exactly  correlated.  Hence  the  diver- 
gence of  methods.  Who  can  tell  a  miner  to 
burden  this  or  that  hole  more  or  less  ? 

In  other  trades  the  best  market  attracts  the 
most  skilled  men.  I  believe  we  have  the  best 
miners  from  Europe,  America,  and  the  Colo- 
nies. It  is  the  system  for  which  the  managers 
are  responsible  that  is  bad.  Read  the  Regula- 
tions and  spare  me  the  judging.  We  never 
hear  of  bad  managers.  Rand  managers  are 
unique.  They  have  the  strongest  x\ssociation 
in  the  world,  for  they  all  belong  to  it ;  yet  they 
object  to  their  miners  being  union  men,  and 
black-list  them  from  end  to  end  of  the  Reef, 
and  brand  them  as  agitators  in  the  gutter  Press, 
that  heir  of  their  adoption.  The  miners  receive 
four  dollars  per  day  at  stope-work — a  trifling 


wage  considering  the  relative  purchasing  value 
of  money  here.     Machine-work  averages  five 
dollars.     A  machine-miner  does  his  work  for 
six yearsand  then  dies.   Phthisis  is  the  scourge. 
As  a  contractor  he  is  at  the  height  of  his  pro- 
ducing power  for  about  three    years   in  the 
middle  period  ;    at  the  start  he  is  acquiring 
skill ;  at  the  end  he  is  weakening.    Still  Lionel 
Phillips  says  that  the  Rand  miner  is  paid  too 
much.  The  miners  knowaswell  asMr.  Phillips 
that  the  mines  are  profiting  by  the  exploitation 
of  Kaffir  labour,  and  being  human  they  desire 
a  share  of  the  boodle.     The  miner  takes  his 
life  in  his  hand  when  he  goes  down  in  that  skip 
you  mention  ;  it  jumps  the  rails  twice  a  week 
in  the  average  Rand  mine  ;    he  converts  the 
useless  latent  power  of  the  native  into  a  use- 
ful profitable   asset.     It    is   a    psychological 
peculiarity  of  the  native  that  his  ideas  of  direc- 
tion and  motion  are  round.   It  may  be  en\'iron- 
ment.      His  first  idea  is  circular.     It  may  be 
fashioned  from  the  sun  and  moon,  as  his  edu- 
cation proceeds  from  observation  only.     True 
it  is,  that  all  their  fortifications  are  circular, 
his  utensils,  his  hut,  threshing-floors,  wicker 
cages,  baskets,  pottery,  and  cooking  gear  are 
round.     I  have  put  in  four  pegs  for  a  rectan- 
gular prospecting  pit  in  Rhodesia  and  started 
a  native  accordingly.     I  came  back  in  three 
days.     It  was  a  circular  pit.     The  savage  re- 
verted to  type.     Therefore  the  native  cannot 
be  a  miner,  and  the  Rand  miner  is  therefore 
the  greatest  creator  of  wealth  for  his  company, 
as  he  controls  30  boys  as  his  quota,  whereas 
the  skilled  artisan  or  engine-driver  only  aver- 
ages one  boy,  and  then  more  in  the  manner  of 
a  body  servant  than  a  labourer.     Why  then 
should  the  mining  bosses  single  out  the  miner 
for  sharp  practices  and  cuttingdevices  ?   Think 
of  the  dangers  and  the  pitfalls  of  the  mining 
Regulations.     You  are  liable  not  only  for  your 
own  transgressions,  but  for  everyone  of  those 
black  men.     As  much  as  ^20  is  a  common 
fine  imposed  on  a  miner  when  proved  guilty 
of  a  transgression.     I  f  you  cut  a  '  boy's  '  ticket 
for  not  drilling  3  feet  or  allowing  his  hole  to 
deviate,  he  may  either  crack  your  head  with 
his  4-pound  hammer,  or  light   a   fuse   in  a 
charged  borehole,  or  more  often  violently  pull 
the  fuse  from  its  anchorage.     These  are  a  few 
of  the  Rand  miner's  grievances.    Another  real 
grievance  is  the  Identification  Pass  (an  out- 
come of  the  strike)  that  the  miner  must  carry. 
It  lends  itself  to  blacklisting,  as  a  shorthand 
stroke  half -hidden   denotes  a   lot,   after    the 
fashion  of  a  marked  coin  in  the  trapping  sys- 
tem.    Espionage  and  nepotism  are  rife.     Ac- 
cording to  the  Ordinance  of  1903,  to  obtain  a 


382 


THE    MINING    MAGAZINE 


mine  overseer's  certificate  you  must  have  one 
year's  charge  or  under-charge  of  the  under- 
ground works,  that  is,  you  must  become  a 
shift-boss.  That  billet  is  the  gift  cf  the  man- 
ager ;  the  position  connotes  a  knowledge  of 
mining,  but  it  is  not  borne  out  in  fact.  The 
man  selected  may  possess  a  blasting  ticket,  as 
is  often  the  case.  So  the  best  billets  are  con- 
served for  one  class  or  persuasion. 

One  more  word — I  fear  I  am  trespassing, 
yet  I  refrain  from  flattering  you  :  How  about 
the  bad  managers.  Walk  through  the  drifts 
of  the  Rand  mines,  and  observe  where  the 
seam  or  reef  is  faulted,  whether  it  was  a  nor- 
mal, reverse,  or  step  fault.  As  soon  as  the  dis- 
location was  struck,  right  away  they  cross- 
cutted  in  foot  and  hanging  ;  not  finding  the 
reef  there  they  drove  on,  then  stripped  the 
drift  to  a  width  of  20  feet ;  and  yet  they  could 
not  find  the  displaced  reef  till  back-stoping 
was  resorted  to.  Finally,  compare  the  drifts 
advanced  in  pre-war  days,  when  the  miner 
was  paid  and  appreciated,  with  the  modern 
manager's  workings.  Something  needs  blot- 
ting out ;  better  it  would  be  to  totally  blot  out 
the  present  methods.  Pardon  the  split- infini- 
tive. Moral :  A  miner's  mistake  may  cost  the 
company  a  few  sovereigns,  a  manager's  mis- 
take may  cost  hundreds. 

Reef  Miner. 

Krugersdorp,  September  25. 

Percentage  of  Recovery. 

The  Editor  : 

Sir — In  your  issue  of  September  1911,  I 
note  Mr.  Theodore  J.  Hoover's  comment  on 
Percentage  of  Recovery,'  giving  belated  ac- 
knowledgment to  an  excellent  article  on  the 
same  topic  by  Dr.  Rudolf  Gahl,  of  Morenci, 
Arizona.  Mr.  Hoover  speaks  disparagingly  of 
The  Western  Chemist  and  Metallurgist,  in 
which  Dr.  Gahl  was  pleased  to  present  his 
ideas,  calling  it  a  "  backwoods  "  magazine. 

So  far  from  being  a  "  backwoods  "  maga- 
zine, it  was  the  journal  of  a  live  and  ambitious 
society  of  chemists  and  metallurgists  in  the 
western  part  of  the  United  States,  and  Dr. 
Gahl's  contribution  to  it  was  typical  of  the 
earnest  and  able  support  which  it  received  for 
six  years.  It  was  known  to  the  other  metal- 
lurgical societies  of  the  world,  and  the  articles 
contributed  to  it  were  frequently  re-printed 
by  the  leading  technical  journals. 

But  if  Mr.  Hoover  never  knew  of  the  exist- 
ence of  The  Western  Chemist  and  Metallur- 
gist, he  probably  does  not  now  know  that  it  is 
no  more,  and  that  he  spoke  disrespectfully  of 
the  departed.     Neither  does  he  know  that  the 


six  volumes  of  the  journal  undoubtedly  contain 
other  excellent  articles  of  which  he  might  well 
be  apprised. 

Denver  is  not  in  the  backwoods,  and  the 
metallurgists  who  regard  it  as  their  profes- 
sional centre  are  keenly  alive  and  aware  of 
what  is  going  on.  Hence,  it  was  with  some 
degree  of  surprise  that  many  of  us  saw  Mr. 
Hoover's  original  article  appear  two  years 
after  a  similar  article  had  been  published  by 
us  and  re-printed  in  other  places.  The  Journal 
of  the  Chemical,  Metallurgical  and  Mining 
Society  of  South  Africa  gave  extensive  notice 
to  Dr.  Gahl's  article  in  its  issue  for  November 
1909,  as  also  did  Electrochemical  and  Metal- 
lurgical Industry  in  July  1909. 

We  are  within  that  circle  of  those  who,  as 
Mr.  Hoover  says,  "  knew  all  about  it  a  long 
time  ago."  Apparently  "  backwoods  "  is  a  re- 
lative term,  and  the  timber  may  grow  most 
densely  in  the  world's  greatest  centre  of  popu- 
lation. One  is  entitled  to  wonder  where  Mr, 
Hoover  has  been,  and  to  suggest  that  many 
good  things  come  out  of  regions  which  to  him 
are  "  backwoods,"  but  which  in  reality  are  on 
the  frontier  of  knowledge  and  progress.  H  e  has 
opened  himself  to  criticism  by  this  futile  at- 
tempt to  cover  his  embarrassment  by  a  slur- 
ring reference  instead  of  a  frank  acknowledg- 
ment. 

H.  C.  Parmelee. 
Denver,  October  9. 

[Mr.  Parmelee  is  quite  right  in  sending  this 
protest,  but  we  think  there  are  mitigating  cir- 
cumstances. As  far  as  Mr.  Hoover  is  con- 
cerned personally,  we  may  say  that,  though 
The  Western  Chemist  and  Metallurgist  was 
an  excellent  paper,  it  had  little  circulation  in 
this  country.  As  far  as  we  are  ourselves  con- 
cerned, Mr.  Gahl's  article  was  published  be- 
fore The  Mining  Magazine  was  in  existence, 
and  for  some  time  afterward  we  did  not  see  our 
Denver  contemporary  ;  otherwise  the  special- 
ists who  attend  to  our  '  Precis  of  Technology  ' 
would  certainly  have  done  full  justice  to  Mr. 
Gahl.  The  American  Press  seems  to  have 
been  equally  ignorant  of  Mr.  Gahl's  contribu- 
tion, for  Mr.  Hoover's  original  article  on  the 
subject  was  published,  as  a  novelty,  in  the  En- 
gineering ami  Min  ingjournaloi  June  11,1910. 
This  we  abstracted  in  our  '  Precis  of  Techno- 
logy '  in  our  issue  of  July  1910,  and  accom- 
panied it  by  editorial  comment.  At  our  re- 
quest, Mr.  Hoover  elaborated  the  applications 
of  the  formulas  in  an  article  appearing  in  our 
succeeding  issue,  and  since  then  we  have  had 
numerouscontributions  from  appreciative  read- 
ers who  have  been  able  to  give  amplifications 


NOVEMBER,    1911 


383 


of  the  idea  drawn  from  their  own  experience. 
In  any  case,  however,  Mr.  Gahl  cannot  claim 
absolute  priority,  for,  as  we  recorded  in  our 
issue  of  October  1910,  the  first  printed  evi- 
dence of  the  use  of  these  formulas  was  pro- 
vided by  Mr.  J.  M.  Callow  in  the  catalogue 
of  the  General  Engineering  Co.  of  Salt  Lake 
City,  published  in  the  year  1907. — EDITOR.] 

Buying  Prospects. 

The  Editor  : 

Sir — Your  editorial  on  Buying  Prospects,' 
in  the  September  issue,  recalls  what  has  often 
occurred  to  me  regarding  the  saving  that  would 
result  if  it  were  possible  to  form  a  Clearing 
House  of  information  about  the  world's  mines 
and  districts.  It  outrages  one's  sense  of  eco- 
nomy to  see  engineer  after  engineer  wasting 
time  and  money  in  running  over  the  same  old 
holes  in  the  ground,  each  one  not  aware,  per- 
haps, that  he  has  had  many  predecessors. 

Such  an  idea  might  prove  feasible  if  it  were 
taken  up  by  a  well-established  engineering 
firm,  as  a  branch  of  its  business.  Such  a  cen- 
tral bureau  might  make  arrangements  with 
scattered  syndicates  and  practicing  engineers 
to  forward  to  it  such  information  as  they  were 
free  to  send  regarding  their  territory.  Or,  upon 
inquiry  from  a  client  of  this  bureau  for  infor- 
mation regarding  a  certain  property  or  com- 
pany, the  bureau  could  send  out  to  its  asso- 
ciates asking  them  if  they  had  first-hand  data 
on  this  particular  subject.  The  names  of  such 
syndicates  and  engineers  that  had  replied  in 
the  affirmative  could  then  be  given  to  the 
bureau's  client  for  his  choice  as  to  whose  data 
he  cared  to  call  for.  A  scale  of  modest  fees 
could  be  established. 

However,  there  are  some  drawbacks  and 
fine  points  to  such  a  scheme.  As  far  as  ex- 
ploration syndicates  who  have  obtained  their 
information  at  their  own  cost  are  concerned, 
there  would  appear  to  be  no  objection  to  the 
idea,  from  their  standpoint  ;  of  course,  in  the 
case  of  an  engineer,  his  information,  for  the 
most  part,  belongs  to  those  who  have  paid  for 
it.  How  is  it  from  the  mine-owner's  stand- 
point ?  His  mine  is  his  secret,  and  it  is  to 
his  advantage  that  many  engineers  come  to 
look  at  it,  with  the  hope  that  one  may  finally 
see  more  in  it  than  the  others  did  ;  besides  he 
may  have  done  more  development  work.  In 
reply  it  might  be  asked,  what  is  the  difference 
in  paying  a  fee  for  existing  information  and 
paying  for  similar  information  obtained  anew? 
And  it  could  also  be  maintained  that  such  exist- 
ing information  might  help  the  mine-owner, 
for,  while  perhaps  the  mine  is  not  what  a  cer- 


tain crowd  is  looking  for,  it  might  be  just  the 
kind  of  a  proposition  that  would  suit  another. 
Another  drawback  to  the  general  acceptance 
of  this  clearing  house  idea  has  to  do  with  per- 
sonality. In  all  professions  the  personal  equa- 
tion enters  largely,  and  is,  as  a  rule,  the  cause 
of  the  engineer  being  retained  ;  it  is  his  per- 
sonal opinion  that  is  wanted. 

W.  N.  CUMMINGS. 

Tucson,  Arizona,  October  14. 

Pyrites  Deposits  of  Huelva. 

The  Editor  : 

Sir— Mr.  H.  F.  Collins' article  on  'The 
Pyrites  Deposits  of  Huelva,'  which  appeared 
in  your  August  issue,  is  of  particular  interest 
to  students  of  these  deposits,  more  especially 
as  it  has  been  written  by  one  with  consider- 
able experience  of  the  orebodies  throughout 
that  region.  If  others  could  be  induced  or 
permitted  similarly  to  record  the  results  of 
their  extended  observations  we  should  gaia 
much. 

It  is  doubtful  whether  the  secondary  en- 
richment of  the  deposits  has  been  discussed 
to  the  extent  that  Mr.  Collms  suggests.  It 
seems  to  me  that  that  phase  of  the  subject 
has  received  far  too  little  serious  attention. 
It  is  also  questionable  whether  his  substitu- 
tion of  'surface'  for  secondary'  enrichment  is 
altogether  a  happy  thought.  Does  not  'sur- 
face' enrichment,  as  a  general  term,  connote 
'gossan'  enrichment,  as  distinct  from  the  sul- 
phide enrichment  beneath  the  gossan  ? 

The  writer's  description  of  banded  and  com- 
plex ores,  and  of  variation  in  composition,  is 
valuable,  but  it  appears  to  me  that  he  lays 
undue  stress  on  the  assumed  abnormality  of 
the  larger  orebodies.  While  great  variations, 
both  in  structure  and  composition,  are  ad- 
mitted, and  must  impress  themselves  on  those 
who  have  to  do  with  the  sampling  and  ship- 
ment of  the  ore,  I  think,  ne\ertheless,  that 
the  geologist  is  fully  justified  in  regarding  the 
Huelva  deposits  in  general  as  low-grade  lenti- 
cular pyritic  masses,  any  notable  variation  in 
composition  being  a  departure  from  the  nor- 
mal type.  It  is  natural  that  these  mineralo- 
gical  variations  should  assert  themselves  most 
strikingly  in  the  smaller  orebodies,  since  the 
physical  and  chemical  conditions  of  deposition 
would  be  most  readily  disturbed,  with  result- 
ing irregularities  in  composition,  where  the 
zone  of  ore  deposition  was  restricted  in  size, 
and  the  ore-bearing  solutions  consequently  re- 
stricted in  their  action  and  more  sensitive  to 
disturbing  influences. 

Mr.  Collins'  contention  that  there  has  been 


384 


THE    MINING    MAGAZINE 


a  secondary  deep-seated  enrichment  by  chal- 
copyrite,  accompanying  the  intrusion  of  the 
basic  dikes,  is  an  important  one.  If  it  is  up- 
held by  future  research,  it  will  explain  some 
peculiar  mineralogical  features.  My  own  ob- 
servations^''  led  me  to  the  conclusion  that  the 
basic  dikes  had  immediately  preceded  the 
primary  deposition  of  the  ore,  and  this  view 
was  supported  by  petrographical  work  at  Es- 
peranza,  which  Mr.  Collins  cites  as  an  instance 
in  support  of  his  view.  At  all  events,  his 
suggestion  of  a  Tertiary  age  for  the  basic  in- 
trusives  is  bold,  and  is  unsupported  as  yet  by 
any  authoritative  work  on  the  field-relations 
of  these  intrusives  throughout  the  area.  It 
is  doubtful  if  the  point  will  be  cleared  up  with- 
out a  good  deal  of  petrographical  work,  at 
Huelva,  and  in  the  adjoining  areas  to  the 
north  and  northeast. 

These  are  surely  scientific  issues,  but  they 
are  of  sufficient  interest  to  economic  geologists 
to  permit  of  their  being  pointed  out  here,  and 
there  are  many  who  would  welcome  a  more 
extended  discussion  of  these  points  by  Mr. 
Collins,  as  well  as  by  others  on  the  spot. 

A.    M.    FiNLAYSON. 

Maymyo,  Upper  Burma. 
September  24. 

Statements  of  Cost. 

Sir — The  American  custom  of  referring  to 
the  cost  of  copper  production  as  6,  9,  12  or 
any  other  number  of  cents  per  pound  appears 
not  to  be  well  understood  on  this  side  of  the 
water,  if  my  experience  is  a  general  one. 
Here  it  is  often  taken  to  be  an  expression 
of  the  level  of  operating  cost  apart  from  any- 
thing else,  and  the  inference  appears  to  be 
that  a  company  that  produces  copper  at  8 
cents  per  lb.  must  necessarily  be  working  at 
much  lower  cost  than  one  which  produces  at 
12  cents.  As  a  matter  of  fact  the  expression 
is  a  function  of  two  things,  namely,  the  metal 
production  per  ton  of  ore  and  its  cost,  and 
herein  has  its  value. 

Some  copper  mines  at  Ely,  for  instance, 
produce  copper  at  about  8  c.  per  lb.  and  as 
the  production  is  about  20  lb.  per  ton  the 
total  cost  per  ton  of  ore  is  only  $r60.  If  a 
mine  in  a  locality  in  which  costs  were  $10  per 
ton  were  producing  copper  at  8  c.  per  lb.,  its 
yield  would  have  to  be  125  lb.  per  ton.  If  the 
production  dropped  to  83  lb.  per  ton  it  would 
increase  the  cost  to  12  c.  per  lb.  A  cost  of 
8  cents  per  ton  is  therefore  possible  on  the 
widely  varying  yields  of  20  and  1251b.  cop- 

*  Economic  Geology.    Vol.  V,  1910,  pp.  357-406. 


per,  respectively.  It  would  be  wrong  to  as- 
sume from  this  that  a  copper  ore  yielding  20 
lb.  of  metal  per  ton  can  always  be  profitably 
worked. 

The  value  of  the  expression  is  only  one  in- 
dicative of  the  margin  of  profit  available  in 
the  selling  price  of  the  metal.  We  must  know 
the  original  content  per  ton,  the  practicable 
percentage  of  extraction,  and  the  cost  of  pro- 
duction before  it  can  be  made  to  mean  any- 
thing more  than  this. 

My  real  reason  for  touching  upon  this  sub- 
ject, however,  is  to  ask  why,  if  this  method  of 
speaking  of  copper  production  be  a  good  one, 
it  should  not  be  applied  to  the  ounce  of  silver, 
using  the  same  reservations.  If  we  know 
that  a  company  can  only  produce  silver  at 
a  cost  of  2s.  6d.  per  ounce  we  know  it  is  an 
unprofitable  concern,  provided  of  course  it 
produces  only  silver.  If  on  the  other  hand 
we  are  told  that  it  produces  silver  at  8  or  10 
or  18  pence  we  can  at  once  get  some  idea  of 
its  profit-earning  capabilities.  In  Mexico, 
for  instance,  we  read  the  statement  that  a 
certain  company  is  handling  560 -gramme 
silver  ore  but  is  making  no  profits,  while 
another  company  on  450-gramme  ore  is  do- 
ing well.  The  value  of  silver  expressed  in 
grammes  conveys  no  very  clear  idea  to  the 
English  reader  and  there  is  undoubtedly  a 
good  deal  of  confusion  on  this  point.  But 
most  people  know  that  the  present  price  of 
silver  is  in  the  neighbourhood  of  2s.  per  oz. 
and  if  the  ounce  of  silver  were  treated  in  the 
same  way  as  the  pound  of  copper  there  would 
be  a  complete  understanding  on  at  least  one 
important  point. 

G.  A.  Denny, 

London,  October  30. 

Malaria. 

The  Editor  : 

Sir  —  Mr.  Stephen  Lett's  letter  in  your 
October  issue  is  particularly  interesting  to 
me  as  I  have  often  mentioned  to  friends  the 
great  relief  that  I  also  discovered  accidentally, 
some  years  ago,  when  travelling  in  South 
America  during  a  particularly  bad  mosquito 
season.  Having  none  of  the  acknowledged 
specifics  at  hand,  I,  in  despair,  tried  the  effect 
of  ordinary  '  Odol,'  with  most  beneficial  re- 
sults. 

I  do  not  write  the  above  as  an  advertise- 
ment for  '  Odol,'  but  only  in  case  other  readers 
of  your  magazine  may  find  themselves  in 
similar  predicaments. 

Noel  G.  Hackney. 

London,  October  21. 


NOVEMBER,    1911 


385 


PRECIS  OF  TECHNOLOGY 

Boring  for  Coal  in  Buckinghamshire. — Some  inter- 
est has  been  aroused  by  the  news  that  prospecting  for 
coal  is  being  conducted  by  means  of  bore-holes  in 
Buckinghamshire,  in  the  neighbourhood  of  Calvert  on 
the  Great  Central  Railway.  An  article  on  the  subject 
appeared  in  the  Colliery  Guardian  for  October  20, 
in  which  a  plain  unbiassed  statement  of  the  geological 
possibilities  is  given,  with  a  view  to  counteract  some 
of  the  erratic  paragraphs  that  have  appeared  in  the 
daily  papers.  Coal  is  not  at  present  worked  in  any 
Midland  county  nearer  to  London  than  Warwick  and 
Leicester,  and  the  number  of  col- 
lieries there  are  not  so  numerous  as 
in  Nottingham,  Stafford  and  Derby 
farther  to  the  northwest.  In  the 
Buckingham  district  only  two  bore- 
holes have  been  sunk,  one  at  Burford 
in  Oxfordshire,  30  miles  southwest  of 
Calvert,  and  the  other  at  Bletchly, 
twelve  miles  east  of  Calvert.  The 
Burford  boring  cut  the  coal  measures 
at  1202  ft.-,  and  that  at  Bletchly,  after 
passing  through  the  oolite,  encounter- 
ed granite  boulders.  The  problem 
of  the  possible  occurrence  of  the  coal 
measures  in  the  neighbourhood  of 
the  Charnian  axis  has  always  troubled 
geologists.  This  axis  is  a  line  (N.W. 
and  S.E  )  of  upheaval  and  folding 
most  prominent  in  the  Charnwood 
Forest  district  of  Leicestershire, 
where  Pre-cambrian  rocks  and  gra- 
nite and  greenstone  come  to  the  sur- 
face. It  marks  a  buried  mountain 
range  dating  from  before  the  Trias. 
It  is  generally  held  that  coal  measures 
may  be  found  in  the  folds  of  these  sub- 
terranean ranges.  P.  F.  Kendall  offer- 
ed evidence  on  this  subject  before  the 
last  Royal  Commission  on  Coal  Sup- 
plies. It  is  stated  that  boring  at  Cal- 
vert was  undertaken  because  of  the 
discovery  of  a  natural  gas  similar  to 
fire-damp.  One  favourable  circum- 
stance is  that  the  secondary  strata  in 
the  district  are  not  thick,  so  that  if  any 
coal  is  to  be  found,  it  should  be  cut  at 
a  depth  of  not  more  than  1000  ft. 

Wire  Ropes  for  Mining  Purposes. — 
At  the  October  meeting  of  the  Mining 
Institute  of  Scotland,  Dugald  Baird, 
of  the  Lugar  Ironworks,  Ayrshire, 
read  a  paper  on  wire  ropes  as  applied 
to  mining  ;  this  was  full  of  practical 
hints  to  those  in  charge  of  hoisting  and 
hauling  operations.  He  began  by  comparing  various 
qualities  of  iron  and  steel  wire  used  in  the  manufacture 
of  ropes,  and  discussed  the  methods  of  testing  them, 
and  afterwards  proceeded  to  make  suggestions  as  to  the 
design  of  the  winding-engines,  drums,  pulley-wheels, 
keps  or  supports  for  the  cage  at  surface,  so  as  to  en- 
sure the  best  results  from  the  ropes.  He  made  a 
number  of  suggestions  as  follow  :  (/)  The  winding 
drum  should  be  at  a  sufficient  distance  from  the  shaft 
to  prevent  side-wear  of  the  rope.  [2)  The  drum  should 
be  so  wide  that  the  rope  will  occupy  only  one  course. 
{3)  The  diameter  of  the  drum  and  pulley-wheels  should 
not  be  less  than  a  hundred  times  the  diameter  of  the 
rope,  and  a  thousand  times  the  diameter  of  the  thickest 
individual  wire  in  the  rope.     (4)  A  rope  lasts  longer 


if  there  are  no  keps  at  the  surface,  and  if,  when  the 
cage  is  at  the  bottom,  no  slack  is  allowed.  (5)  The 
pulley-wheels  should  be  designed  with  such  dimen- 
sions that  they  do  not  remain  stationary  for  a  time 
after  the  rope  is  let  out  or  continue  to  revolve  after 
the  cage  comes  to  the  surface  ;  this  problem  has  not 
yet  been  solved.  (6)  Ropes  should  be  made  with 
Lang's  lay,  unless  locked-coil  or  other  special  designs 
are  used.  (7)  When  the  drums  are  lagged  with  wood 
It  is  advisable  to  have  a  helical  groove  so  that  the  rope 
will  not  rub  on  itself  as  it  is  wound  and  unwound. 
The  pitch  of  the  groove  should  be  such  that  a  space 
of  ^.2  in.  is  left  between  each  coil.     This  arrangement 


is  specially  necessary  when  the  drum  is  close  to  the 
pit,  for  under  this  condition  the  rope  will  otherwise 
mount  on  itself.  (8)  The  individual  wires  of  the  rope 
should  be  as  large  as  possible  consistent  with  item  (.>l. 
(9)  It  is  best  to  galvanize  the  ropes,  except  in  such 
circumstances  where  a  thick  preservative  coat  of  paint 
can  be  put  o.i ;  but  such  a  coat  has  a  disadvantage 
because  it  prevents  examination.  (10)  The  effective 
life  of  a  rope  is  difficult  to  judge,  but  it  is  certain  that 
a  rope  should  be  used  for  only  a  limited  period  ;  li  ta 
7  years  are  the  minimum  and  maximum  in  the  experi- 
ence of  the  writer,  and  he  is  of  opinion  that  a  galvan- 
ized rope  may  be  safely  used  half  as  long  agciin  as  a 
bright-wire  rope.  (//)  Ropes  used  in  sinking  should 
be  of  the  non-rotating  type.     These  are  constructed 


386 


THE    MINING    MAGAZINE 


of  two  concentric  layers  laid  in  opposite  directions. 
Such  ropes  are  not  particularly  necessary  for  ordinary 
winding.  Flat  ropes  are  sometimes  used,  consisting 
of  six  or  eight  small  ropes  stitched  together  with  bes- 
semer  wire.  Their  advantage  is  that  they  give  an 
ideal  scroll  -  drum  movement,  and  thus  engines  of 
smaller  size  can  do  the  same  work  as  the  larger  engines 
do  with  a  parallel  drum.  They  are,  however,  more 
expensive,  and  they  give  trouble  by  splitting  apart  ; 
their  life  is  not  so  great  as  the  ordinary  rope.  The 
author  suggested  two  subjects  for  discussion.  One 
was  whether  the  rope  coming  off  the  top  of  the  wind- 
ing drum  or  that  coming  off  the  under  side  has  the 
longer  life.  The  general  opinion  is  in  favour  of  the 
former  case,  as  both  the  bends  it  makes  are  in  the 
same  direction,  but  the  author's  experience  is  that 
there  is  little  difference.  The  second  point  was  whether 
a  rope  lasts  longer  when  the  drum  is  lagged  with  wood 
or  when  the  rope  rests  direct  on  the  metal.  It  is 
usually  supposed  that  the  advantage  is  with  the 
wooden  surface,  but  the  author  considers  that  ex- 
perience ought  to  be  recorded  in  this  connection. 

Metallurgy  at  Globe  &  Phoenix.— In  our  July 
issue,  H.  T.  Brett  contributed  an  article  on  metallur- 
gical'practice  at  the  Globe  &  Phoenix  gold  mine  in 
Rhodesia  and  recorded  that,  though  the  treatment  by 
amalgamation  in  the  stamps,  the  extraction  from  con- 
centrate, and  the  handling  of  slime  after  weathering 
were  giving  good  results,  the  antimony  in  the  ore 
militated  against  the  success  of  cyanide  treatment  of 
the  sand-tailing.  He  mentioned  that  probably  this  part 
of  the  plant  would  have  to  be  abandoned  and  roasting 
and  sliming  adopted.  The  Rhodesian  Mining  Re- 
view for  September  6  describes  the  new  plant  now 
being  erected.  The  capacity  will  be  300  tens  per  day, 
100  tons  being  current  sand,  and  200  tons  accumu- 
lated sand  of  which  there  is  more  than  100,000  tons. 
There  are  three  Edwards  roasting  furnaces,  and  special 
grates  have  been  designed  so  as  to  make  it  possible  to 
use  Wankie  coal.  The  steel  chimney  is  140  ft.  high  and 
7  ft.  diam.  The  roasted  ore  on  discharge  will  be 
mixed  with  cyanide  solution  and  elevated  by  a  tailing 
pump  to  a  classifier.  The  underflow  will  be  treated 
in  12  grinding  pans  placed  in  circuit  and  the  discharge 
returned  to  the  tailing  pump.  The  overflow  of  the 
classifier  will  go  to  2  tube-mills,  each  22  by  5^  ft.,  the 
feed-cones  of  which  are  arranged  so  that  the  final  dis- 
charge shall  be  minus  200.  The  slime  will  go  to  a 
Dorr  thickener  and  thence  to  8  agitator-vats  20  ft.  high 
by  8  ft.  diameter.  The  time  occupied  in  agitation  will 
be  12  hours.  The  resulting  gold-bearing  solution  will 
be  removed  by  continuous  decantation  in  Dorr  thick- 
eners. The  Merrill  zinc-dust  precipitation  process  will 
probably  be  adopted.  It  will  be  seen  that  the  plant 
is  to  contain  the  latest  ideas  in  gold  metallurgy. 

Treating  Copper-Lead  Matte.— In  Metallurgie  for 
June,  R.  Hesse  describes  a  new  method  of  treating 
leady  copper  matte,  particularly  in  connection  with 
this  product  coming  from  the  Otavi  company's  mine 
in  German  Southwest  Africa.  The  Otavi  matte  aver- 
ages 40%  copper,  24%  lead,  and  11%  iron.  The 
method  is  to  roast  it  to  4%  sulphur  and  fuse  with 
silica  ;  the  result  is  the  production  of  copper  contain- 
ing a  small  amount  of  lead,  while  the  rest  of  the  lead 
and  the  iron  go  into  the  slag.  The  copper  is  refined, 
and  the  lead  slag  so  produced  is  sent  to  the  lead- 
smelting  furnace,  along  with  the  slag  produced  in  the 
first  reaction. 

Forbes'  Slime  Thickener. — In  the  Engineering  and 
Mining  Journal  for  October  7,  D.  L.  H.  Forbes  de- 
scribes his  slime  thickener  in  use  at  the  El  Tigre  cya- 
nide plant  at  Ysabal,  Sonora,  Mexico.     This  machine 


is  a  variation  of  that  invented  by  J.  N.  V.  Dorr, 
but  the  revolving  rakes  are  discarded  for  the  spiral 
paddles  shown  in  the  accompanying  illustration,  and 
it  is  claimed  that  by  this  arrangement  the  settled  slime 
is  moved  to  the  centre  more  evenly  and  without  eddies. 
Two  of  these  machines  have  been  at  work  for  over  a 
year,  for  the  purpose  of  removing  the  gold-bearing 
solution  after  cyanidation  in  Pachuca  vats.  There 
are  four  spiral  paddles  arranged  as  shown,  of  such  de- 
sign that  the  blades  are  at  45°  to  the  radius.  These 
revolve  once  in  5  minutes,  and  the  power  for  each 
machine  is  J  hp.  From  100  to  130  tons  dry  are  treated 
per  machine  per  day.     The  pulp  enters  at  the  dilution 


4  X  C  Swij  Bnca 

8M' 


SjxcUl  Vtrllcit 
Bearing 


r 


/       Bear!  HI 


sizszzszib: 


of  1  part  solid  to  2  or  2|  parts  solution  by  weight,  and 
the  discharge  is  1  :  Ij.  The  material  treated  is  a  mix- 
ture of  natural  clay  slime  and  tube-mill  product,  and 
85  to  90%  will  pass  200  mesh.  The  clay  forms  about 
one  third  of  the  mixture,  and  it  is  particularly  difficult 
to  settle. 

Geology  of  Cobalt.— We  have  already  on  several 
occasions  described  the  geology  and  the  ore  deposits 
of  the  Cobalt  area,  Ontario,  Canada;  nevertheless,  it 
is  opportune  to  quote  an  article  appearing  in  the  En- 
gineering and  Mining  Journal  for  September  30  by 
Willet  G.  Miller,  the  Provincial  Geologist  of  Ontario. 
Mr.  Miller  was  the  first  geologist  to  write  a  report  on 
the  district,  eight  years  ago.  He  and  his  staff  have 
recently  made  another  complete  examination,  and  an 
official  bulletin  will  be  issued  shortly.  The  article 
now  referred  to  is  an  outline  of  the  matter  contained 
in  this  bulletin.  The  basement  rocks  of  the  district 
belong  to  the  Keewatin  series  of  basic  volcanic  types 
usually  known  as  green  stones  or  green  schists,  to- 
gether with  dike  rocks  and  some  sedimentaries.  These 
rocks  at  one  time  formed  the  surface  of  the  land,  and 


NOVEMBER,    1911 


387 


they  were  afterward  eroded  into  hills  and  hollows, 
and  covered  with  conglomerates  and  other  fragmental 
rocks  of  the  Huronian  period.  Subsequently  a  quartz- 
diabase  sill  was  intruded  through  both  the  Keevvatin 
and  Huronian,  having  a  thickness  of  500ft.,  and  a  dip 
of  17°  toward  the  south  or  southeast.  The  accom- 
panying generalized  vertical  section  shows  how  the 
land  surface  has  since  then  been  removed,  leaving 
little  of  the  Keevvatin  hanging  wall.  The  map  shows 
two  or  three  isolated  remnants  of  the  hanging  wall 


mineral  veins,  but  gives  the  view  generally  held  that 
they  have  been  formed  by  magmatic  water,  introduced 
at  the  same  time  as  the  sill,  and  working  upward  and 
downward  through  the  cracks  on  the  sill  and  the  rocks 
above  and  below.  He  is  of  opinion  that  meteoric 
water,  that  is,  water  working  downward  from  the  sur- 
face, played  an  important  part  also,  at  least  as  regards 
some  of  the  ores.  He  considers  that  the  diabase  sill 
was  subjected  to  the  action  of  both  magmatic  and 
meteoric  water,  and  that  minerals  were  thus  extracted 


GENERALIZED    VERTICAL    SECTION    OF    COBALT   DEPOSITS. 


HANOI 


.0       '^^'^         C 


SCALE  OF  MILES 
0  8  16l 


Geological  Map  of  Cobalt. 


Faulting  Linen  at  Cohall. 


resting  on  the  diabase.  Of  these  (A)  is  on  the  Nova 
Scotia  property  and  (B)  is  on  the  Colonial.  In  the 
main  part  of  the  hanging  wall  (C)  are  the  Temiskam- 
ing  and  Beaver  veins.  At  (D)  and  (£)  the  sill  has 
been  eroded  and  has  exposed  the  foot-wall.  In  the 
vertical  section  (T)  represents  the  Temiskaming  vein 
in  the  wall  above  the  sill  ;  (C)  is  a  type  of  vein  m  the 
Huronian  ;  (N)  a  type  of  vein  in  the  Keewatin  below 
the  sill,  such  as  No.  26  on  the  Nipissing  ;  and  (K)  is 
a  type  of  vein  in  the  sill  itself,  such  as  No.  3  on  Kerr 
Lake.  Nearly  90%  of  the  ore  so  far  produced  has 
come  from  veins  on  the  foot-wall  of  the  sill,  a  fact 
chiefly  due  to  so  large  a  part  of  the  overlying  rocks 
having  been  removed.  Mr.  Miller  does  not  commit 
himself  definitely  to  a  theory  of  the  formation  of  the 


to  be  re-deposited  elsewhere  :  also  that  some  of  the 
minerals  now  in  the  veins  may  have  been  dissolved 
out  of  the  wall  rocks.  The  cobalt-nickel  ores  are 
generally  of  greater  age  than  those  of  silver,  so  it  is 
possible  that  the  magmatic  water  played  the  more 
important  part  in  their  deposition,  anil  that  the 
meteoric  wa'er  were  largely  instrumental  in  the  de- 
position of  the  silver.  He  does  not  consuier  that 
secondary  enrichment  is  a  feature  worth  as  much 
consideration  as  other  geologists  have  given  to  it.  As 
regards  faulting,  he  shows  that  faults  with  small  dis- 
placements are  numerous,  and  that  they  extend  in 
point  of  time  from  the  Keewatin  to  the  C.lacial  period. 
The  most  important  fault  so  far  examined  has  a  throw 
of  300  to  400  ft.  and  is  approximately  parallel  to  the 


388 


THE    MINING    MAGAZINE 


main  La  Rose  vein.  The  faults  may  be  classified  into 
two  systems  of  weakness,  one  northwest  and  south- 
east and  the  other  northeast  and  southwest.  The 
former  is  the  more  striking,  as  it  is  in  the  direction 
followed  by  the  Ottawa  and  the  Montreal  rivers. 
The  author  refers  to  a  recent  discovery  of  mercury 
ore  at  the  Nipissing,  but  no  exact  information  is  yet 
to  hand. 

Smelter  Gases. — In  the  Mining  and  Scientific 
Press  for  September  23,  Stewart  W.  Young  describes 
his  '  thiogen  '  process  for  treating  sulphurous  acid  gas 
and  reducing  it  to  sulphur,  that  is  being  tested  at  San 
Francisco  with  a  view  to  its  application  to  the  neutrali- 
zation of  smelter  gases.  The  reaction  on  which  it  is 
based  is  that  between  a  hydrocarbon  and  sulphurous 
acid,  whereby  sulphur  is  liberated  and  carbonic  oxide 
and  water  formed.  This  reaction  requires  a  high  tem- 
perature, and  the  evolution  of  carbonic  oxide  is  an- 
other drawback.  Mr.  Young  has,  however,  elabora- 
ted a  modified  process  by  means  of  which  a  lower  tem- 
perature is  possible  and  the  effluent  gases  consist  of 
nothing  but  carbonic  acid  and  water.  The  sulphurous 
acid  is  passed  through  calcium  sulphide,  with  the  pro- 
duction of  calcium  sulphite  and  free  sulphur.  After 
the  removal  of  the  latter  the  sulphite  is  heated  with  a 
hydrocarbon  and  reduced  again  to  sulphide,  which  is 
returned  for  re-use,  and  carbonic  acid  and  water 
formed.  The  process  has  yet  to  be  tested  on  a  prac- 
tical scale  and  its  cost  ascertained,  but  it  is  of  con- 
siderable interest  and  may  serve,  in  spite  of  its  cost,  to 
settle  the  much-vexed  question  of  smelter  smoke. 

The  Economics  of  Tube-Milling. — At  the  October 
meeting  of  the  Institution  of  Minmg  and  Metallurgy 
a  paper  on  this  subject  by  H.  Sfandish  Ball  was  sub- 
mitted. The  paper  was  the  thesis  for  the  science  de- 
gree at  McGill  University,  at  which  the  writer  was 
studying  as  Research  Scholar  of  the  Transvaal  Cham- 
ber of  Mines.  The  paper  is  a  lengthy  one  and  may 
be  divided  into  two  parts,  the  first  being  a  general 
resume  of  the  history  and  applications  of  the  tube- 
mill  and  the  theories  of  rock-crushing,  and  the  other 
a  record  of  experimental  investigations  undertaken  by 
the  author.  The  first  series  of  tests  were  made  with 
a  view  of  ascertaining  the  best  rate  of  feed,  the  rate  of 
revolution  (41),  the  percentage  of  moisture  (38%),  and 
the  pebble  load  (1200  lb.)  being  constant,  the  inside 
dimensions  of  the  mill  being  3i  ft.  length  and  2  ft. 
10  in.  diameter,  and  the  lining  being  silex  brick  set 
in  cement.  The  feed  was  sand  approximately  18 
mesh,  and  the  discharge  was  analysed  for  minus  120 
mesh.  Six  tests  were  made  with  feeds  varying  from 
72  tons  to  23  tons  per  24  hours.  It  was  found  that  the 
test  at  the  rate  of  186  tons  gave  the  highest  mechanical 
efficiency  and  the  highest  crushing  efficiency.  The 
author  examines  the  results  by  means  of  diagrams. 
The  second  series  of  tests  was  made  with  a  view  of 
ascertaining  the  best  proportion  of  moisture  The 
feed  was  constant  at  126  tons  per  24  hours  and  the 
pebble  load  and  the  number  of  revolutions  the  same 
as  before.  The  result  was  that  37  7%  of  moisture 
{presumably  by  weight)  was  the  most  efficient  from 
the  point  of  view  of  power  used  for  the  production  of 
equal  quantities  of  minus  120  material.  This  figure 
agrees  fairly  well  with  the  38-4%  of  Walter  Neal  in 
the  Mining  and  Scientific  Press  for  April  2,  1910, 
and  the  385%  found  by  G.  O.  Smart  in  his  paper  on 
the  Caldecott  cone  read  before  the  Chemical,  Metal- 
lurgical, and  Mining  Society  of  South  Africa  on  May 
10,  1910.  A  third  series  of  tests  was  made  with  regard 
to  the  pebble  load,  and  theconclusion  was  that  10501b., 
equal  to /g  ths  of  the  internal  volume,  was  the  best. 
A  fourth  series  was  undertaken  in  order  to  find  the 


most  efficient  speed  of  revolution  ;  the  feed  was  72 
tons  per  24  hours,  the  pebble  load  1200  lb.,  and  the 
moisture  38%.  The  revolutions  per  minute  varied 
from  33  to  46,  and  it  was  found  that  both  the  mechani- 
cal and  the  crushing  efficiencies  were  greatest  when 
the  rate  was  37  per  minute.  Mr.  Ball  quotes  the  view 
of  J.  W.  Bell,  his  professor,  to  the  effect  that  the  most 
efficient  percentage  of  moisture  coincides  with  the 
percentage  of  voids.  Mr.  Bell  has  already  discussed 
this  matter  in  our  pages,  and  it  has  been  pointed  out 
that  there  is  a  fallacy  here,  because  in  the  tube-mill 
tests  the  percentage  is  by  weight  and  in  the  calculation 
of  voids  the  comparison  is  by  volume.  Mr.  Ball's 
paper  will  prove  of  value  and  will  be  closely  read  by 
all  interested  in  tube-mill  practice. 

Lapland  Iron  Ores. — At  the  October  meeting  of  the 
Iron  and  Steel  Institute,  L.  Leigh  Fermor,  of  the 
Indian  Geological  Survey,  presented  a  paper  written 
for  the  purpose  of  traversing  W.  H.  Herdsman's 
paper,  read  at  the  May  meeting,  on  the  origin  of  the  iron 
ore  deposits  in  Swedish  Lapland.  Mr.  Herdsman  had 
brought  forward  a  theory  that  these  deposits  are  meta- 
morphosed sedimentaries  of  the  Cambrian  or  Silurian 
age,  and  his  chief  argument  was  that  this  theory  ac- 
counts for  the  presence  of  phosphorus.  Mr.  Fermor 
shows  that  Mr.  Herdsman  is  at  variance  with  Conti- 
nental and  .\merican  geologists,  and,  in  order  that  a 
succinct  account  shall  appear  in  England  written  by 
an  English  geologist,  he  reviews  the  opinions  of  these 
geologists  and  pomts  out  Mr.  Herdsman's  fallacies.  O. 
Stutzer,  a  Norwegian  investigator,  had  contributed 
an  elaborate  paper  to  the  Iron  and  Steel  Institute  in 
1907  on  the  geology  and  origin  of  these  ores,  and  it 
was  in  fact  his  paper  that  Mr.  Herdsman  attacked. 
Per  Geijer  has  also  vritten  an  elaborate  monograph 
on  the  same  subject  in  the  Swedish  language  Mr. 
Fermor  gives  an  account  of  his  visit  to  these  deposits 
at  the  time  of  the  Stockholm  geological  congress,  and 
of  the  discussions  with  the  many  other  eminent  authori- 
ties who  were  present  on  the  same  occasion.  In  his 
opinion  the  evidence  irresistibly  points  to  the  conclu- 
sion that  the  iron  ore  deposits  and  associated  por- 
phyries have  been  produced  by  magmatic  differentia- 
tion from  syenitic  magmas.  Sometimes  the  magnetite- 
apatite  rocks  have  segregated  practically  in  situ  in  the 
syenitic  rocks  ;  at  other  times  they  have  segregated 
from  the  syenitic  magma  at  a  lower  level,  and  have 
been  erupted  separately  from  the  syenitic  rocks  ;  and 
sometimes  subsequent  metamorphism  has  imparted  a 
parallel  structure  to  both  the  orebodies  and  the  en- 
closing syenitic  rocks. 

Electric  Smelting  of  Zinc  Ores. — In  our  last  issue 
we  gave  a  lengthy  abstract  of  reports  on  the  electric 
furnace  at  Trollhattan,  used  for  smelting  complex 
zinc-lead  sulphides.  Our  figures  taken  from  J.  C. 
Moulden's  report  on  the  probable  results  of  treating 
concentrated  slime  from  the  Central  mine  at  Broken 
Hill,  owned  by  the  Sulphide  Corporation,  were  in- 
correct, the  error  being  due  to  Mr.  Moulden  including 
the  cost  of  roasting  the  slime  in  both  the  cost  of  ma- 
terial and  the  cost  of  treatment.  The  correct  figures  are 
as  follow  :  Cost  of  ore  per  metric  ton  at  Trollhattan 
£5.  Os.  4d.,  value  of  recoverable  metal,  £9.  9s.  lid., 
cost  of  treatment  £3.  Os.  7d  ,  profit  £l.  9s.  The 
material  is  figured  as  containing  32%  zinc,  23%  lead, 
and  25  oz.  silver  ;  the  recovery  is  estimated  at  75% 
zinc,  80%  lead,  and  80%  silver;  and  the  price  of 
metals  is  taken  at  /22  zinc,  /12  lead,  and  26d.  silver. 
The  error  in  our  figures  is  found  in  the  total  cost  at 
the  smelter  which  was  given  at  £5.  8s  5d.  instead  of 
£5.  Os.  4d.,  the  difference  being  the  cost  of  roasting  ; 
otherwise,  the  figures  for  the  value  of  the  recovered 


NOVEMBER,    1911 


389 


metals  ;^9.  9s.  Ud.,  the  cost  of  treatment  £i.  Os.  7d., 
and  the  margin  of  profit  £l.  9s.,  were  given  correctly! 
Imbert-Fitzgerald  Zinc  Process. — In  a  recent  issue 
we  noted  in  our  column  '  Current  Literature  '  a  paper 
read  at  the  Fiftieth  Anniversary  Congress  of  the  Mas- 
sachusetts Institute  of  Technology,  by  F.  A.  J.  Fitz- 
gerald, of  Niagara  Falls,  describing  his  electric  furnace 
that  is  at  work  at  the  Hohenlohe  Hutte,  Germany,  for 
treating  zinc  ores  by  the  Imbert  reaction.  We  are 
given  to  understand  that  this  process  is  at  present  in- 
teresting people  connected  with  Broken  Hill,  and  that 


furnace.  In  the  furnace  designed  by  Mr.  Fitzgerald, 
the  heat  is  generated  electrically  by  the  resistance  of 
arches  (R),  built  up  of  interlocking  plates  of  carbon 
In  the  accompanying  illustrations,  the  cover  of  the 
furnace  is  not  shown  ;  it  contains  feed-pipes,  and  pipes 
for  the  escape  and  collection  of  the  zinc  vapour.  The 
current  enters  at  (P),  passes  along  one  resistor  (R), 
back  by  way  of  the  conductor  (E)  to  the  other  resistor, 
and  out  at  (Q).  The  power  absorbed  by  the  furnace 
is  150  kilowatts.  Mr.  Fitzgerald  does  not  say  any- 
thing of  the  capacity  of  the  furnace  or  of  the  results 


-e 


FinST    FORM    OF    THE    IMBERT-FITZOEHALD    ZINC    FUHNACE. 


omething  may  be  heard  of  it  before  long  in  London 
financial  circles,  so  we  return  to  the  subject  again  and 
give  an  illustrated  abstract  of  Mr.  Fitzgerald's  paper. 
The  Imbert  process  is  a  modification  of  the  well-known 
reaction  whereby  metallic  iron  will  release  the  zinc 
and  lead  of  blende  and  galena,  and  combine  with  the 
sulphur.  He  makes  the  reaction  take  place  in  a  bath 
consisting  of  a  mixture  of  oxide  and  sulphide  of  iron. 
The  zinc  is  volatilized,  and  the  lead  and  silver  fall  to 
the  bottom  of  the  furnace,  the  other  two  products 
being  slag  formed  from  thegangue,  and  an  iron  matte 
containing  the  sulphur.  This  matte  can  be  partly 
roasted  and  used  again.  It  will  be  seen  that  reduction 
to  metal  is  not  effected  by  carbon,  as  is  usual  in  zinc 
furnaces,  and  that  no  preliminary  roasting  has  to  be 
done.  Heat  is  required  to  bring  the  charge  to  the 
temperature  at  which  the  leaction  takes  place,  about 
1400°C.     Imbert's  difficulty  was  to  devise  a  suitable 


achieved,  but  no  doubt  this  information  will  be  given 
shortly.  One  advantage  possessed  by  this  furnace 
over  others  recently  proposed  for  the  treatment  of 
zinc  lead  slime  is  that,  as  roasting  is  eliminated,  the 
loss  of  silver  by  volatilization  will  be  obviated. 

Since  writing  the  above,  we  have  received  another 
paper  by  Mr.  Fitzgerald,  read  before  the  American 
Electrochemical  Society  on  September  21.  In  this 
communication,  he  shows  that  the  heat  losses  with 
this  type  of  resistor  were  so  great  tiiat  its  position  and 
structure  ha\e  had  to  be  modified.  We  have  also 
seen  the  specification  of  United  States  patent  994,217 
granted  to  Mr.  Fitzgerald's  co-worker,  John  Tiiomson, 
in  which  the  resistor  is  placed  in  a  sealed  box  im- 
mersed in  the  bath  itself.  Tiiis  arrangement  would 
obviate  the  dissipation  of  the  heat  radiated  from  the 
top  of  the  arch,  that  was  the  cause  of  the  abandon- 
ment of  the  form  of  furnace  as  illustrated. 


390 


THE    MINING    MAGAZINE 


Zinc  Extraction  by  Bisulphite  Process.— T/je  Min-  rent  is  15.      All  the  metals  but  sih-er  and  lead  go  into 

inii   Journal    (London)    for  October  21   contains  an  solution  and  these  are  precipitated  as  chloride,  while 

article  professing  to  describe    the  bisulphite  process  the  copper  accumulates  in  the  electrolyte  which  even- 

for  the  treatment  of  complex  and    intimately-mixed  tually  has  to  be  renewed.  The  gold  is  chiefly  deposited 

sulphide  ores  containing  zinc.     The  article  is  a  long  on  the  cathodes,  but  some  is  precipitated  and  becomes 

one  but  the  information  afforded  is  meagre,  and  quite  mixed   with   the  chlorides.     The  chloride  residue  is 

valueless  to  the  metallurgist  who  is  desirous  of  ap-  washed  in  hot  water  for  the  removal  of  the  lead,  and 

praising  its  practical  value.     As  the  process  is  being  treated  with  granulated  zinc  and  sulphuric  acid  for 

tried  on  Mount  Read  and  other  zinc-lead-pyrite  ores  the  recovery  of  the  silver  as  metal,  which  with  the 

found  in  Tasmania,  we  make  this  brief  reference  to  precipitated  gold  is  sent  back   to  the  refining  ce   s. 

what  may  be  considered  the  official  statement.     The  The  spent  electrolytes  from  the  gold  and  silver  cells, 

process  is  associated  with   the  names  of  Sulman  &  and   the  various  wash  waters  go  to   vats  containing 

Picard    Hommel,  and  Fradd,  though  we  believe  that  scrap  iron,  where  the  copper  and  lead  are  precipitated, 

the  first-named  have  no  connection  with  it  nowadays.  The   precipitate  is  refined  in   a  sulphate  electrolyte. 

The  article  states  that  the  ore  is  crushed  and  roasted  Any  metals  of  the  platinum  group  in  the  bullion  are 

in  the  usual  way,  and  the  sulphurous  acid  gas  passed  recovered  here.  ,      „.    • 

through  pulp  consisting  of  roasted  ore  and  water       In  The  Ashio  Copper  Mine,  Japan.— The  M/h/»^  and 

this  way   the   soluble   bisulphite,    Zn  H.,    (SOj.,,    is  Scientific  Press  for  October   14   contains  a  lengthy 

formed       The  resulting  solution  is  taken  to  vats  where  and  highly  interesting  account  of  the    Ashio  copper 

insoluble  monosulphite,  Zn  SO.^,  is  precipitated.   This  mine,  written  by  Thomas  T.  Read,  who  made  a  per- 

monosulphite    when    heated  is   dissociated   into  zinc  sonal  inspection  in  1910.     This  mine  is  the  largest 

oxide  and  sulphurous  acid.      The  zinc  oxide  is  free  producer  of  copper  in  Japan,  and  is  followed  closely 

from  lead  and  is  a  desirable  raw  material  for  the  zinc  by  the  Besshi  and  Kosaka,  the  outputs  for  1910  being 

distiller.  The  remaining  pulp,  after  the  removal  of  respectively  7049,  6629  and  6286  long  tons.  The  posi- 
the  bisulphite,  can  be  treated  for  lead  or  copper  in  tion  of  these  mines  is  shown  on  the  accompanymg 
any  otdinarv  way  according  to  its  composition.  map.  The  Ashio  mine  belongs  to  the  Furukawa  com- 

The  Standard  Tin  Contract.— Elsewhere  in  this  pany,  a  private  corporation  that  owns  fifteen  copper 
issue  we  refer  to  the  new  basis  of  contract  for  the  sale  mines,  three  silver  mines,  and  seven  coal  mines.  It 
of  metallic  tin,  adopted  bv  the  London  Metal  Ex-  was  discovered  in  1608,  but  its  active  development 
change.  In  the  report  issued  in  connection  with  it.  dates  from  1877  when  it  was  acquired  by  the  present 
the  following  analyses  were  published  :  owners.     Its  success  was  the  foundation  of  a  fortune, 

Tin        Antimony     Arsenic       Lead        Bismuth      Copper  Iron  Silver         Sulphur 

%  %  %  %  %  %  %  '^o. 

Banka    99'950  •■.  0007  -.  nil  ...  trac-  ...         nil  •■  0018  •.  0015  ...  nil  .■■  trace 

Billiton 9'rq60  ...  OOO'b  ...  nil  ...  nil  ■•         nil  ...  0  023  ...  ml  ...  ni  ...  nil 

Pmang 99939  -.  trace  ...  0013  ...  trace  ...         nil  ...  0015  ...  0028  ...  ml  ...  0  004 

Singapore     99-870  ...  O'OOS  OWS  ...  O'OS*  ...  0  003  ...  0352  ...  0  003  ...  0006  ■■  0  005 

Mt.  Bischoff 99795  ...  O'OIS  ...  0'063  ...  0^037  ..  O'OOS  ...  0'035  ...  0^042  ..  trace  ...  0  O^S 

Pyrmont   99'938  ■■  0017  ...  0'019  .•■  trace  ...         nil  ...  0022  ■■  trace  ...  nil  ...  0  004 

Irvinebank  99^580  ■  0062  ...  003+  ..  0221  ...  0025  ...  0126  ...  0  002  ...  0  018  ■  •  0  004 

Williams-Harvey  (1) 99-860  ...  Q-OIS  ...  0-040  ...  000*  •  0005  ...  00*7  ...  O-QOI  ■•  ml  ...  0  006 

Wilhains-Harvey  (2) 99-560  ...  0-166  ...  0-037  ...  0-162  ...  0-007  ...  0500  ...  0  005  ...  trace  ...  00  3 

Williams-Harvey  (2a)  99350  ...  0-245  ...  0065  0223  ■■  0015  ...  0042  ...  0016  -.  trace  ...  0  013 

WiUiams-Harvev  (3) 99200  ...  0300  ...  0037  .■  0-396  ...  0007  ...  0100  ...  0013  ...  0  014  ...  0  006 

Williams-Harvey  (4) 99641  ...  Q-Oll  ...  0022  ...  trace  ...  0001  ...  0020  ...  trace  ...  trace  0  005 

PenpolKl)    99-720  ..  0-118  ...  0-054  -.  0-041  ...  0007  ...  0  052  ...  0-004  ...  0  009  ■■■  0  00/ 

Penpoll(2)    98-710  ...  0-569  ...  0-042  ...  0  546  •■•  0-055  ..  0-103  ...  0-007  .•  0  015  ..  0  004 

Penpoll  (3)    99-300  ...  0-,325  0-056  ...  0^212  ...  0  050  ...  0-088  ...  0-002  ...  0021  ...  0  009 

Redruth     99-I6O  •■■  0-176  ..  0053  ...  0-177  ...  0^017  ...  0445  ...  O-QU  ...  0  006  ...  0  008 

Goldschmidt(l) 99-860  ...  0-004  ...  nil  ...  0-102  ...        nil  ...  0-04t  ...  trace  ...  nil  ...  trace 

Goldschmidt  (2) 9^-460  ...  0-015  ...  nil  ...  0  425  ...        nil  ...  0069  ■•  trace  .■  ml  ■■  trace 

Goldschmidt  (3) 99-150  ...  O'lZZ  ...  0-046  ...  0-143  ...  0-112  ...  0  352  ...  0^007  ..  0  006  •■.  trace 

Chinese  (1)    99343  ...  0-031  ■■  0  040  ...  0  434  ...  0  007  ..  0052  ...  O'OIO  ..  trace  ...  0  01 

Wing  Hong  (2)    98-662  .•  0-039  .  0  035  ...  1035  ...  0012  ...  0134  ...  0-014  ...  trace  ...  0  011 

Wing  Hong  (3) 95^280  ...  0  ?81  ..  0  050  ...  3-895  ■■  0^020  ...  0106  ...  0026  ...  0  018  •.■  0  008 

Refining  Gold  and  Silver  Bullion.— The  October  and  enabled  the   Furukawa   family  to  purchase  and 

Bulletin  of   the   American  Institute    of    Mining    En-  develop  nearly   all   the   important   copper   and  silver 

gineers    contains    a    lengthy    and    detailed    paper   by  properties  in  the  northeastern  part  of  Hondo  island. 

Edward   B.   Durham  on  the  electrolytic  methods  of  The  mine  is  100  miles  north  northwest  of  Tokio,  and 

refining  gold  and  silver  bullion   used  at  the  United  15  miles  southwest  of  Nikko,  a  little  town  noted  for  its 

States   mint   at    San    Francisco.     The   outline    is  as  magnificent  temples  and   tombs.     Close  by  are  also 

follows:  The  silver  bullion  is  refined  in  an  electro-  the  lake  Chusen-ji,  a  favourite  watering  place,   and 

lytic  bath  consisting  of  an  aqueous  solution  containing  the  hydro-electric  power-house  at  Hosoo.   The  moun- 

3%   silver  as  nitrate,   from   1^  to  2^%   of  free  nitric  tain  containing  the  mine  is  a  volcanic  plug  or  neck  of 

acid,  and   a  little  glue.     The   current   density   is  83  liparite,  upthrust  through  paleozoic  sediments,  mostly 

amperes  per  square  foot  of  cathode  surface,  and  the  clay-slate,  sandstone,  and  quartzite.     This  is  cut  by 

voltage  of  the  entering  current    15.     The   residue  is  innumerable  almost  vertical  veins,  belonging  to  two 

rich  in  gold  and  is  sent  to  the  gold-refining  cells,  while  distinct  series.     The  veins  pass  into  the  surrounding 

copper  and  other  metals  remain  in  solution.      When  sediments,  but  quickly  disappear,  the  structure  form- 

the  solution  contains  8%  copper,  it  is  removed       In  ing  an  excellent  example  of  fissuring  during  coolmg 

the  gold-bullion  refining  process,  the  electrolyte  is  a  and  subsequent  vein  filling    by    the    waters   of   dying 

trichloride  solution  containing,  in  the  first  set  of  cells  vulcanism.     The  order   of   vein-filling  is  as  follows  : 

70  grammes  of  gold  per  litre  and  from  10  to  12%  of  (/)  quartz,  (2)  chalcopyrite  associated  with  some  py- 

free    hydrochloric    acid,    and    in    the    second    set    60  rite,  (i)  pyrite,  sphalerite,  and  galena,  and  (4)  quartz, 

grammes  of  gold  and  the  same  amount  of  free  acid.  The  chalcopyrite  carries  about  2  oz.  silver  and  a  few 

The  current  density  is  90  amperes  per  square  foot  of  grains  of  gold,  and  the  galena  and  sphalerite  contain 

cathode  surface,  and  the  voltage  of  the  entering  cur-  several  ounces  of  silver.    Many  other  copper  minerals 


NOVEMBER,    1911 


391 


are  found  in  small  quantities,  as  also  are  pyrrhotite 
and  arsenopyrite.  The  veins  are  narrow  and  the 
ground  faulted.  In  spite  of  these  natural  drawbacks, 
the  work  is  efficiently  and  cheaply  done  on  a  well- 
devised  contract  system.  Three  eight-hour  shifts  are 
customary  below  ground,  and  two  on  the  surface. 
Access  to  the  deposits  is  gained  by  three  adits,  the 
entries  being  about  equidistant  round  the  base  of  the 
hill.  Two  of  these  adits  are  on  the  same  level  and 
are  connected,  while  the  third,  the  Tsudo,  is  450  ft. 
below  them  and  connected  with  them  by  two  winzes. 
Workings  extend  1100  ft.  above  the  two  upper  adits 
and  are  mostly  exhausted,  and  for  1400  ft.  below, 
sinking  being  still  continued.  There  are  10  winzes 
and  100  miles  of  workings.  Ore-dressing  plants  have 
been  built  at  the  mouth  of  each  adit,  the  principal 
being  at  Tsudo.  The  capacity  of  this  mill  is  250  tons 
per  day  and  the  combined  capacity  of  the  other  two  is 
350  tons.  The  ore  varies  from  1§  to  9%  copper,  aver- 
aging 4%.     As  it  comes  from  the  mine,  it  is  dumped 


gases  do  damage  to  the  surrounding  hills.  Other 
sources  of  trouble  and  expense  are  the  impounding  of 
the  tailing  and  the  slag,  and  the  necessity  for  neutra- 
lizing the  acid  mine-water.  The  blister  copper  is  sent 
down  the  valley  to  the  refinery,  a  short  distance  from 
Nikko.  This  refinery  also  treats  the  products  of  all 
the  other  mines  of  the  Furukawa  group. 

CURRENT    LITERATURE. 

Winding  Engine. — Engineering  for  October  27  de- 
scribes, with  full  drawings,  the  5500  hp.  winding  engine 
built  by  the  Sandycroft  company  for  the  Champion 
Reef  mine. 

Shaft-Sinking   in  Wet   Ground.  —  At   the  August 

meeting  of  the  Chemical,  Metallurgical,  and  Mining 
Society  of  South  Africa,  B.  C.  Gullachsen  described 
the  method  of  sinking  a  shaft  at  the  Ferdinand  colliery, 
Silesia,  through  wet  ground. 


1          0 

A 

\ 

A 

LEGEND 

+ 

Petroleum 

9 

Gold 

a 

Sihcr 

9 

Coiiper 

<? 

Iron 

+ 

Coal 

\ 

Sulpl'.ur 

MINERAL    MAP    OF   JAPAN    SHOWING    POSITION    OF   ASHIO    COPPEH    MINE From  the  Engineering  Mngn:im-. 


on  a  80  mm.  grizzly  ;  the  oversize  is  sorted  into  rich 
ore,  low-grade  ore,  and  waste,  the  low-grade  being 
afterwards  spalled  to  pass  the  grizzly  ;  the  undersize 
is  sent  to  a  set  of  trommels  with  apertures  varying 
from  3  to  40  mm.  The  40  mm.  product  is  sorted  into 
rich  ore,  low-grade  ore,  and  waste,  and  the  low-grade 
ore  is  re-crushed.  The  finer  products  are  jigged  and 
the  coarse  middling  re-crushed  ;  the  finest  products 
are  classified  and  treated  on  Overstrom,  Wilfieys, 
Cammett,  and  Evans  tables.  In  the  smelter,  which 
is  situated  on  the  northeast  side  of  the  hill,  blast-fur- 
naces have  always  been  employed,  and  various  kinds 
of  converters  have  been  used  since  1893  when  the 
original  Manhes  type  was  tried.  The  average  pro- 
duct to  be  smelted  contains  12%  copper,  28%  iron, 
25%  sulphur,  and  32%  silica.  The  fine  material  is 
pot-roasted.  The  gases  from  the  blast-furnaces  are 
sent  through  chambers  where  they  are  exposed  to 
showers  of  lime-water  ;  but  in  spite  of  this,  the  effluent 


Timbering  Shafts — In  the  Mexican  Mining  Jour- 
nal for  October,  H.  G.  Elwes  describes  a  method  for 
timbering  shafts,  using  lighter  pieces  wiih  better 
joints,  suitable  in  places  where  wood  is  scarce. 

Prevention  of  Overwinding. — The  Iron  and  Coal 
Trades  Review  for  October  13  contains  a  description 
of  Landale's  gear  for  preventing  overwinding  used  in 
connection  with  Corliss  engines  at  a  coal  mine  in  Fife. 

Water  Used  in  Cyanidation. —  In  the  Mining  and 
Scientific  Press  for  September  30,  Cleorge  A.  James 
urges  the  necessity  for  carefully  examining  the  quality 
of  the  water  used  in  cyanide  processes,  and  shows 
how  natural  impurities,  both  solid  and  gaseous,  act  as 
cyanides  or  interfere  with  the  extraction. 

Natoma  Dredges.—  In  the  Mining  and  Scientific 
Press  for  October  7,  Newton  Cleveland  describes  the 
new  gold-dredges  built  this  year  for  the  Natomas  Con- 
solidated, operating  alluvial  deposits  in  the  Sacramen- 
to valley,  California 


5—6 


392 


THE    MINING    MAGAZINE 


Cyanide  Bullion. — In  the  Monthly  Journal  of  the 
West  Australian  Chamber  of  Mines  for  August, 
J.  Boyd  Aarons  and  Herbert  Black  describe  the 
method  devised  by  them  at  the  Chaffers  mine  for 
producing  a  higher  grade  of  bullion  from  the  zinc-box 
precipitate. 

Air-Agitation. — In  the  Mining  and  Scientific  Press 
for  September  30,  J.  W.  Swaren  gives  some  interest- 
ing reminiscences  of  the  use  of  air-agitation,  before  it 
was  applied  in  the  Brown  agitator  or  Pachuca  vat  for 
the  treatment  of  slime.  He  shows  that  similar  vats 
were  used  many  years  ago  in  se\'eral  chemical  opera- 
tions, and,  as  far  as  gold  metallurgy  is  concerned, 

E.  L.  Oliver  used  them  at  the  North  Star  mine.  Grass 
Valley,  for  cyaniding  pulp  and  the  electrodeposition 
of  the  dissolved  gold. 

Huntington  Mills. — The  October  Bulletin  of  the 
American  Institute  of  Mining  Engineers  contains  a 
paper  by  C.  C.  Sample  on  the  performance  of  the 
Huntington  mill  at  gold  mines  in  eastern  Nicaragua. 

Mount  Perry. — The  Queensland  Government  Min- 
ing Journal  for  September  contains  a  description  of 
the  Mount  Perry  copper  mining  district  in  Queensland, 
situated  between  Rockhampton  and  Gympie,  and 
owned  chiefly  by   the   Queensland   Copper  Co. 

Problems  in  Copper  Production. — The  Mining 
and  Scientific  Press  for  October  7  contains  a  lengthy 
and  valuable  review  of  the  problems  in  connection 
with  the  exploration,  mining,  concentraiion,  and  smelt- 
ing of  copper  deposits  in  the  United  States  that  have 
been  solved  during  the  last  ten  years. 

Aluminium  Works  in  Norway. — The  Engineer  for 
October  6,  13,  and  20  contains  articles  by  G.  Wiith- 
rich  describing  the  electric  and  hydraulic  works  at 
Vigeland,  in  Southern  Norway,  built  by  the  Anglo- 
Norwegian  Aluminium  Company.  The  capacity  is 
2000  tons  of  aluminium  per  year.  The  works  are 
situated  on  the  Otterdal  river,  ten  miles  from  its  mouth 
at  Christiansand,  and  the  fall  is  59  ft.  The  articledoes 
not  touch  the  metallurgy. 

Electric  Furnaces. — At  the  October  meeting  of  the 
Faraday  Society,  J.  Harden  read  a  paper  on  the  'Para- 
gon' electric  furnace,  and  E.  Kilburn  Scott,  a  paper 
on  the  Hering  'Pinch-Effect'  furnace. 

Electric  Smelting  of  Nickel  Ore. — W.  L.  Morrison 
presented  a  paper  at  the  September  meeting  of  the 
American  Electrochemical  Society,  describing  experi- 
mental work  in  connection  with  the  electric  smelting 
of  nickel  ores  at  Webster,  North  Carolina. 

Vanadium. — Chemical  and  Metallurgical  Engi- 
neering for  October  contains  a  further  instalment  of 
a  lengthy  article  by  W.  F.  Bleecker  on  the  chemistry 
and  metallurgy  of  vanadium. 

Tin  in  Malaya. — In  the  Mining  Journal  for  Octo- 
ber 14,  J.  B.  Scrivenor  commences  a  series  of  articles 
on  prospecting  far  tin  in  the  Federated  Malay  States. 

Transvaal  Coal.  —  The  South  African  Mining 
Journal  for  September  23  and  30  contains  articles  by 

F.  A.  D.  H.  Moseley  on  the  value  of  Transvaal  coal 
for  export  purposes. 

Lorraine  Iron  Ores, — In  Revue  de  Metallurgieiov 
October,  A.  Guillain  reviews  the  iron  ore  production 
of  French  and  German  Lorraine. 

Water  in  Minerals. — Thejournal  of  the  Franklin 
Institute  for  October  contains  an  article  by  W.  W. 
Coblenz  on  the  conditions  of  existence  of  water  of  com- 
bination and  constitution  in  crystals  and  minerals. 

Copies  of  the  original  papers  and  articles  tnen- 
tioned  under  '  Precis  of  Technology  '  and  '  Current 
Literature  '  can  be  supplied  on  application  to  The 
Mining  Magazine. 


BOOKS  REVIEWED 

Graphical  Solution  of  Fault  Problems.  By 
C.  F.  Tolman,  Jr.  Cloth  octavo,  48  pages,  illus- 
trated. San  Francisco  :  Mining  and  Scientific 
Press  :  London  :  The  Mining  Magazine.  F'rice 
4s.  6d. 

Thisisa  reprint,  with  additions,  of  an  excellent  series 
of  articles  that  attracted  much  attention  when  they 
appeared  in  the  Mining  and  Scientific  Press  last 
summer.  We  shall  give  an  extended  notice  in  our 
next  issue. 

Technical  Methods  of  Chemical  Analysis.  By 
George  Lunge,  translated  by  C.  A.  Keane.  Vol.  II. 
Large  octavo,  2  parts,  1294  pages,  illustrated. 
London  :  Gurney  &  Jackson.  Price  63s.  For  sale 
by  The  Mining  Magazine. 

It  is  needless  to  say  that  every  analytical  chemist 
and  assayer  must  own  these  encyclopedic  works  ; 
especially  Volume  II.  now  issued,  as  it  reviews  the 
analytical  methods  in  connection  with  the  metals. 
Other  subjects  included  in  this  volume  of  interest  to 
the  inorganic  chemist  are,  artificial  manures,  explo- 
sives, calcium  carbide  and  acetylene,  illuminating  gas 
and  ammonia. 

The  Chemistry,  Properties,  and  Tests  of  Pre- 
cious Stones.    By  John  Mastin.    Leather,  pocket 
size,  120  pages.  London  :  E.&  F.N. Spon.  Price 2s  6d. 
It  is  difficult  to  read  this  book  with  any  satisfaction 
or  confidence,  for  the  author,  in  attempting,  without 
the  necessary  skill,  to  write  simple  accounts  of  stones 
and  their  properties  has  brought  forth  only  a  series  of 
complicated  statements.     Many  of  his  assertions  make 
even  the  expert  rub  his  eyes. 

The  Copper  Handbook.  \'o1  X.  Compiled  and 
published  by  Horace  J.  Ste\ens,  Houghton,  Michi- 
gan. Price  21s.  For  sale  by  The  Mining  Magazine. 
Stevens'  Copper  Handbook  has  proved  a  most  ser 
viceable  work  of  reference,  and  we  are  glad  to  receive 
a  volume  bringing  the  information  up  to  date.  Our 
readers  should  be  by  this  time  familiar  with  the  scope 
of  the  book,  but  for  those  who  are  not  we  may  say 
that  it  contains  a  reference  to  every  copper  mine  and 
metallurgical  works  throughout  the  world,  with  infor- 
mation as  to  the  directorate,  control,  capitalization, 
and  nature  of  the  business.  These  records  form  the 
bulk  of  the  book,  or,  to  speak  precisely,  occupy  1650 
out  of  the  1900  closely  printed  large-octavo  pages. 
The  rest  of  the  book  is  de\oted  to  a  general  treatise 
on  the  occurrences  of  copper  ores,  the  methods  of 
mining,  and  metallurgical  practice.  We  are  not  de- 
sirous of  belittling  the  hard  work  and  strenuous 
labours  of  Mr.  Stevens,  and  in  fact  we  are  ready  to 
give  him  full  credit  for  excellent  results,  effected 
single-handed  and  in  spite  of  several  untoward  ad- 
verse circumstances.  Nevertheless,  we  are  bound  in 
justice  to  our  readers  to  say  that  the  book  shows  on 
almost  every  page  signs  of  a  lack  of  statistical  adapta- 
bility and  of  the  requisite  facility  of  condensing  and 
systematizing  the  knowledge  placed  at  his  disposal. 
For  instance,  he  complains  in  the  preface  of  the  con- 
tinual increase  in  the  bulk  of  the  book  ;  but  the  expan- 
sion isreally  unnecessary,  and  is  caused  by  the  inclusion 
of  unwieldy  descriptions  of  plants  and  mines  that  are 
of  no  intereGt  to  the  general  reader  and  of  no  value  to 
the  specialist.  For  instance,  Tanganyika  Concessions 
is  held  up  to  ridicule  for  the  space  of  eight  pages,  be- 
ginning with  a  fairy  tale  about  King  Leopold  of  the 
Belgians  giving  the  concession  to  the  Countess  of 
Warwick,  who  in  turn  handed  it  to  Cecil  Rhodes,  fol- 


NOVEMBER,   1911 


393 


lowed  by  references  to  alleged  mines,  elusive  smelters, 
and  jibes  as  to  the  company  becoming  a  fairly  impor- 
tant producer  in  the  21st,  22nd,  or  23rd  centuries.  All 
this  is  yellow  journalism,  and  quite  out  of  place  in  a 
book  of  reference,  which  should  confine  itself,  with 
necessary  discretion,  to  such  official  or  general'state- 
ments  of  the  aims  and  objects  of  each  company  as  are 
available.  Then  again  some  of  the  impolite  entries 
are  due  to  the  carelessness  or  want  of  knowledge  of 
the  compiler  ;  it  is  not  fair,  for  instance,  to  sav  that  a 
letter  was  returned  unclaimed  from  the  "former  office" 
of  a  company,  when  that  company  happens  to  be  an 
old-established  and  reputable  business  house.  Then 
the  glossary  might  well  be  omitted,  for  it  is  only  a 
source  of  merriment  to  the  initiated  and  of  worry  to 
the  inquirer.  A  steam  hammer  is  a  "  heavy  hammer 
actuated  by  steam  or  compressed  air."  Underlay  is 
the  "  mineral  bodies  lying  under  a  given  tract  though 
not  outcropping  on  surface,"  and  underlie  is  "  the 
underlay. ' '  Burrow  is  '  'a  rock  burrow. ' '  An  acid  rock 
is  "  one  in  which  bases  are  combined  with  acids  form- 
ing salts. ' '  An  alkali  is  '  'a  lye  —the  opposite  of  an  acid. ' ' 


Taranaki,  showing  the  three  Sugar  Loaves  sighted 
first  by  Captain  Cook  in  1770.  Later,  in  1838,  atten- 
tion was  drawn  to  Taranaki,  because  it  was  considered 
a  suitable  district  for  the  formation  of  a  colony,  and 
this  agitation  caused  the  British  Government  to'annex 
New  Zealand  before  France  obtained  possession.  The 
presence  of  oil  in  the  district  was  known  to  the  earliest 
settlers,  for  it  was  found  floating  on  the  sea  round  the 
Sugar  Loaves,  and  the  Maories  had  a  tradition  that 
the  oil  was  the  result  of  the  burning  of  bituminous 
matter  in  a  submerged  island.  It  was  not  until  1865 
that  a  technical  e.xamination  of  the  land  on  the  sea- 
shore was  made.  In  that  year  samples  were  sent  to 
London,  and  prospecting  licenses  were  granted  by  the 
Government.  Boring  started  in  1866,  and  gas  and  oil 
were  struck  at  a  depth  of  20  ft.  and  60  ft.  respectively. 
Just  at  that  time  the  New  Zealand  Geological  Survey 
was  created,  and  Sir  (then  Dr.)  James  Hector  was  ap- 
pointed as  chief.  His  first  commission  was  to  report 
on  this  new  oilfield.  The  first  ventures  were  not  suc- 
cessful commercially,  and  the  development  of  the  dis- 
trict lay  in  abeyance  until  1888,  when  interest  was 


OIL    WELL    ON    THE    SEA-SHORE    AT    TARANAKI,    A£If'    ZEALAND. 


Oil  Fields  of  New  Zealand.  By  J.  D.  Henry. 
Cloth,  large  octavo,  350  pages,  with  many  illustra- 
tions. London  :  The  Author,  4  London  Wall  Build- 
ings. Price  15s.  For  sale  by  The  Mining  Maga- 
zine. 

A  year  ago  we  reviewed  '  The  Oil  Fields  of  the 
Empire  '  by  the  same  author,  and  mentioned  that  in 
later  books  he  would  continue  his  records  of  the  oil 
districts  of  other  countries  under  British  rule.  This 
book  on  New  Zealand  is  welcome,  for  little  has  been 
written  on  the  subject,  and  the  resources  of  that  far- 
distant  country  have  hitherto  not  received  the  notice 
they  deserve.  Mr.  Henry  enters  into  full  details  of  the 
history  of  these  deposits,  and  of  their  present  position 
and  prospects.  The  largest  part  of  the  book  is  occu- 
pied with  the  Taranaki  district;  on  the  west  coast  of 
the  North  island,  in  the  neighbourhood  of  New  Ply- 
mouth ;  then  follow  descriptions  of  the  Gisborne  dis- 
trict on  the  opposite  side  of  the  same  island,  and  of 
the  Kotuku  district  on  the  west  side  of  South  island, 
inland  from  Greymouth.  A  short  note  is  added  on 
the  shale  industry  at  Orepuki,  at  the  extreme  south  of 
South  island. 

We  give    herewith  a   photograph    of   the  coast  at 


revived  by  H.  A.  Gordon,  the  Inspecting  Engineer  of 
the  Mines  Department.  In  the  following  year  com- 
panies were  floated  in  England  to  continue  the  work, 
and  in  1906  there  was  a  boom.  Then  came  a  second 
lull.  During  the  last  eighteen  months,  the  deposits 
have  been  attracting  attention  again,  and  probably  we 
shall  hear  more  of  the  Taranaki  oilfield  in  tiie  near 
future.  It  is  interesting  to  note  that  the  celebrated 
iron  sands  are  found  in  the  same  neighbourhood. 

The  Basic  Ophn-Hearth  Steel  Pkocess.  By 
Carl  Dichmann.  Translated  and  edited  by  Alleyne 
Reynolds.  Cloth  octavo,  330  pages,  illustrated. 
London:  Constable  &  Co.  Price  10s.  6d.  For  sale 
by  The  Mining  Magazine. 

The  original  German  edition  of  this  book  was  an 
elaboration  of  a  series  of  articles  that  appeared  in 
Stahl  iDul  Risen,  and  the  translation  lias  been  done 
by  a  practical  and  scientific  steel  metallurgist  inti- 
mately connected  witii  Sheffield.  The  book  is  not  a 
guide  to  the  construction  of  furnaces  or  a  description 
of  the  process  ;  it  consists  rather  of  a  close  examina- 
tion of  the  chemical  and  physical  problems  connected 
with  this  branch  of  metallurgy. 


394 


THE    MINING    MAGAZINE 


COMPANY  REPORTS 

Zaaiplaats  Tin. — This  company  was  registered  in  the 
Transvaal  in  August  1908  to  develop  tin  deposits  in  the 
Waterberg  district.  Crushing  started  in  February  1909. 
The  present  report  covers  the  year  ended  July  31,  and 
shows  that  24,105  tons  of  ore  was  crushed,  yielding 
1763  tons  of  concentrate,  averaging  70%  tin.  This 
sold  for  /190,553,  out  of  which  /1 11, 000  has  been  dis- 
tributed as  dividend,  being  at  the  rate  of  185%  on  the 
capital  /60,000.  Until  the  present  time  the  battery  has 
consisted  of  5  heavy  stamps  and  10  light  ones  ;  the  lat- 
ter are  now  being  replaced  by  15501b.  stamps  similar  to 
the  other  heavy  ones.  This  has  been  made  necessary 
by  the  increasing  hardness  of  the  ore.  It  is  further 
announced  that  another  20  are  to  be  added,  as  the  ex- 
tent of  the  orebodies  is  found  to  be  far  greater  than  was 
at  first  supposed.  Additional  dressing  plant  will  also 
be  required,  as  the  cassiterite  tends  to  become  of  finer 
grain  and  more  disseminated  in  depth  ;  also  a  roasting 
furnace  to  deal  with  the  pyritic  matter  which  is  making 
its  appearance.  The  report  of  Hans  Merensky  is  in- 
corporated with  the  directors'  report  ;  to  this  we  have 
already  referred  in  our  pages.  The  mine  manager  is 
G.  H.  Furner,  and  during  his  absence  on  leave  his 
place  is  occupied  by  C.  Fred  Thomas,  late  of  South 
Crofty. 

Rooiberg  Minerals. — This  company  was  formed  in 
the  Transvaal  in  May  1908  for  the  purpose  of  develop- 
ing tin  deposits  situated  on  the  northern  slope  of  the 
Rooiberg  range  of  hills,  40  miles  west  of  Warmbaths 
and  70  miles  north  by  west  of  Pretoria.     The  control 
was  originally  with  the  Oceana  companv,  but  passed 
later  to  the  Anglo-French-Farrar  group.     Edward  J. 
Way  is  consulting  engineer,  and  Amos  Treloar,  late  of 
East  Pool,  is  manager  of  the  concentration  plant.  The 
report  now  issued  covers  the  year  ended  June  30,  and 
shows  that  17,781  tons  of  ore  was  sent  to  the  mill  esti- 
mated to  contain  7%  tin,  and  that  1077^  short  tons  of 
concentrate  was  produced  averaging  67%  metal,  being 
a  recovery  of  58%  of  the  content.     The  revenue  from 
the  sale  of  concentrate  was  ;^115,563,  and  the  net  profit 
was  /52,674,  out  of  which  the  first  dividend  yet  dis- 
tributed was  paid,  absorbing  /13,500  or  at  the  rate  of 
7i%.  ;^4821  written  off  for  depreciation,  and  /39,468 
carried  forward.      Some  months  ago  we  recorded  that 
a  new.  treatment  plant  was  being  designed  ;    that  is 
now  being  built  at  a  cost  of  about  /40,000.     By  its 
means  it  is  expected  that  the  extraction  will  be  greatly 
improved,  andinadditontheaccumulatedslime  treated. 
The  reserve  of  ore  on  June  30  was  estimated  at  21,650 
tons,  averaging  4J%  recoverable  content,  but  Mr.  Way 
points  out  that  these  figures  are  quite  unreliable,  for 
thin  seams  of  pure  cassiterite  are  continually  being 
found  on  sloping  that  could  not  be   detected    when 
making  an  estimate  of  reserve.     He  has  found  by  ex- 
perience that  the  mill-screen  samples   are  generally 
higher  than  the  mine  samples.     Mr.  Way  reports  that 
his  scheme  of  increased  development  has  been  retarded 
by  scarcity  of  labour. 

China  Clay  Corporation. — As  recorded  in  our  issue 
of  April  1910,  this  company  was  formed  by  L.  Ehrlich 
&  Co.  to  acquire  a  tract  of  virgin  china-clay  land  on 
the  southern  edge  of  Dartmoor,  Devonshire.  E.  T. 
McCarthy  is  on  the  board,  R.  Hansford  Worth  is  con- 
sulting engineer,  and  John  Mutton  is  manager.  The 
issued  capital  consists  of  ;^150,000  in  ordinary  shares, 
which  were  all  issued  as  fully  paid  to  the  vendor  and 
to  the  underwriters,  and  120,000  preference  shares  of 
£\  each,  on  which  12s.  6d.  has  been  called  up.  The 
report  now  issued  covers  the  period  from  the  incor- 
poration of  the  company  to  June  30  of  this  year.  The 


time  has  so  far  been  occupied  with  preparatory  work  ; 
a  railway  is  being  built  to  connect  the  Redlake  pro- 
perty with  the  Great  Western  railway  at  Bittaford  ; 
the  peat  overburden  has  been  removed,  and  a  shaft 
sunk.  This  development  work  has  fully  confirmed 
the  estimate  as  to  the  value  and  extent  of  the  deposit 
over  the  tested  area  of  98  acres,  namely,  2\  million 
tons.  A  pipe-line  8  miles  long  has  been  laid  to  Cant- 
rell,  where  the  concentration  and  treatment  plant  is 
being  erected.  Of  the  working  capital  subscribed, 
/25,435  was  paid  as  part  purchase  price,  and /29, 602 
has  been  spent  on  the  above-described  work,  leaving 
a  sum  of  about  /65,000  available  for  the  completion 
of  the  programme.  It  is  interesting  to  note  that  tlie 
peat  overburden  is  proving  useful  as  fuel. 

Amalgamated  Zinc  (De  Bavay's). — As  recorded  in 
our  issue  of  November  1909,  this  company  was  formed 
in  Melbourne  to  acquire  and  extend  the  flotation  pro- 
cess developed  by  A.  J.  de  Bavay.     The  plant  treats 
zinc  tailing  from  the  North  and  South  mines,  the  con- 
trol of  which  is  in  the  same  hands,  the  Baillieu  group, 
and  the  company  has  more  recently  obtained  the  con- 
tract for  the  tailing  from  Block  10  mine.     The  report 
now  issued  covers  the  nine  months  ended  June  30  last, 
the  odd  period  being  due  to  the  desirability  of  having 
the  half-yearly  accounts  made  up  at  the  same  time  as 
those  of  the  North  and  South  mines.     During  the  nine 
months,  319,256  tons  of  material  was  treated,  pro- 
ducing 93,973  tons  of  zinc  concentrate,  assaying  48  1  % 
zinc,  67%  lead,  and  9  1  oz.  silver,  together  with  1457 
tons  of  lead  concentrate,  assaying  55%  lead,  28  2  oz. 
silver,  and    11  6%   zinc.     The  accounts  are  credited 
with  if 271, 503,  being  the  amount  receivable  from  the 
European  zinc  smelters  calculated  on  /22  as  the  price 
of  the  metal.     As,  however,  the  contract  of  sale  pro- 
vides for  payment  for  any  half-year's  deliveries  at  the 
average  price  during  the  succeeding  half-year,  it   is 
clear  that  this  figure  will  be  greatly  exceeded  owing  to 
the  recent  advance  in  the  price  of  the  metal.     After 
payment  for  the  purchased  tailing  and  of  expenses  of 
treatment  and  administration,  the  profit  was  ;^9S,301. 
To  give  an  idea  of  the  possible  eventual  profit  after 
readjustment  of  prices,  we  may  mention  that  if  the 
average  price  of  zinc  was  ;^25  per  ton  the  profit  would 
be  /134,841.    The  directors  have  distributed  /_  75,000 
as  dividend,  being  at  the  rate  of  15%. 

Hainault — This  mine  is  in  the  northwestern   part 
of  the  Golden  Mile  of  Kalgoorlie,  and  has  been  a  pro- 
ducer since  1901.     The  profits  have  not  been  so  great 
as  at  some  of  its  neighbours  to  the  east  and  south,  and 
the  total  dividends  have  only  been  40%  on  a  capital 
of  ;^150,000.   The  control  is  in  Scotland  and  Archibald 
L.  Hay  is  manager.     The  metallurgical  treatment  is 
different  from  the  present  method  adopted  in  the  dis- 
trict, and  is  in  fact  a  modified  form  of  that  generally 
in  vogue  in  early  days.    Forty  stamps  crush  to  8  mesh, 
and  Cobbe  amalgamating  pans  reduce  it  to  40-mesh. 
The  discharge  from  the  pans  is  classified  into  sand 
and  slime,  and  the  two  concentrated  separately     The 
concentrate  is  roasted  and  cyanided,  and  the  tailing 
from  the  concentrators  is  cyanided.     The  report  for 
the  year  ended  May  31  shows  that  62,332  tons  of  ore 
was  treated,  yielding    gold   worth   ;^84,237.      These 
figures  compare  with  69,098  tons  and  :^93,639  during 
the  preceding  year.     The  expenses  at  the  mine  were 
;^58,2H,  ;^13,229  was  charged  to  mine  development, 
and  /5449  has  been  allowed  for  depreciation.     After 
paying   London   expenses  and    taxes,    the   profit   was 
/4607,  out  of  which  /3750  was  paid  as  dividend,  being 
at  the  rate  of  2J%.     The  development  work  has  dis- 
closed about  as  much  ore  as  was  sent  to  the  mill,  and 
the  reserve  remains  at  approximately  100.000  tons. 


NOVEMBER,    1911 


395 


averaging  6f  dwt.  On  the  eastern  side  of  the  property 
the  conditions  are  hopeful  for  future  additions  to  the 
reserve. 

Whim  Well  Copper. — This  company  was  formed 
in  1906  to  acquire  a  copper  property  in  the  northern 
part  of  West  Austraha.  in  the  West  Pilbara  district, 
and  near  the  coast  to  the  east  of  Roeburne.  H.  R. 
Sleeman  is  engineer.  The  present  report  covers  the 
15  months  ended   March    31,    the   odd  period  being 


caused  by  the  shifting  of  the  time  for  making  up  the 
accounts  from  the  hot  season,  when  any  additional 
work  is  an  unbearable  burden  to  the  mine  staff.  In 
our  notice  last  year,  we  recorded  that  the  deposit  is  in 
a  flat  lode,  oxidized  at  the  surface  and  showing  sul- 
phides below  by  drilling.  The  deposit  is  extensive, 
and  much  of  it  is  of  high  grade.  At  the  present  time 
the  best  ore  is  shipped  to  Europe  and  sold  to  smelters. 
During  the  15  months  under  review,  11,636  tons  was 
exported,  averaging  14%  copper,  having  a  gross  value 
of  ;f97,000.  After  mining,  shipping,  and  smelters'  ex- 
penses were  paid,  the  profit  was  ;;f  18,600,  which,  with 
the  ;^1 7, 127  carried  forward  from  the  previous  year, 
brought  the  profit  to  /35,727.     Out  of  this,  ;^23,250 


hasjjeen  distributed  as  dividend,  being  at  the  rate  of 
12J%.  Much  attention  has  been  given  to  the  ques- 
tion of  economically  concentrating  the  lower-grade  ore, 
and  It  was  eventually  decided  to  adopt  the  '  Murex  ' 
magnetic  process.  A  plant  capable  of  treating  200  tons 
per  day  is  now  being  constructed. 

Mexico  Mines  of  El  Oro.— This  company  used  to 
be  in  the  control  of  the  Exploration  Company,  having 
been  formed  in  1904  to  acquire  the  Mexico 'property 
containing  the  same  vein,  the  San  Rafael,  as  the  El 
Oro  and  the  Esperanza.  Toward  the  end  of  1910, 
the  directors  resigned  owing  to  the  opposition,  on  the 
part  of  the  French  and  Pearson  groups  of  share- 
holders, to  the  conservative  policy  of  the  Exploration 
Company.  The  office  was  removed,  the  board  recon- 
stituted, A.  F.  Main  resigned  the  management  of  the 
mine  to  Fergus  L.  Allan,  and  Andre  P.  Oriffiths  was 
appointed  consulting  engineer.  The  report  now  is- 
sued covers  the  year  ended  June  30,  and  shows  that 
136,408  tons  of  ore  was  raised.  From  this,  gold-silver 
bullion  worth  $1,528,229  was  extracted,  being  a  re- 
covery of  #11  20  per  ton,  of  which  about  %9  was  gold 
and  the  remainder  silver.  The  average  extraction 
%.      In  the  profit  and  loss  account,  the  in- 


was 


come  from  the  sale  of  bullion  was  ;f 31 1,758.  and  the 
expenses  in  Mexico  ;^126,467.  Expenditure  on  im- 
provements, particularly  in  connection  with  the  re- 
timbering  of  the  North  shaft,  absorbed  /24.200,  and 
/8000  was  allowed  for  depreciation.  The  dividends 
amounted  to  ;f  144.000.  being  at  the  rate  of  80%  per 
annum  on  the  capital  /180,000.  The  total  distribution 
to  date  has  been  /427,500,  and  in  addition  ;^137,342 
has  been  spent  out  of  revenue  on  capital  account.  Mr. 
Allan  reports  that  the  South  shaft  has  been  re-tim- 
bered to  1100  ft.,  that  is,  between  Levels  5  and  6, 
and  that  the  North  shaft  has  been  sunk  to  1305  ft.,  or 
35  ft.  below  the  seventh  level.  Of  the  ore  raised,  the 
largest  amounts  came  from  the  7th,  6th,  and  4th 
levels,  and  smaller  quantities  from  the  8th  and  5th. 
The  development  work  consisted  of  11,208  ft.  of  driv- 
ing and  929  ft.  of  shaft-sinking.  The  ore  reserve  was 
increased  by  35,000  tons  and  on  June  30  stood  at 
318,720  tons,  averaging  $9  50  gold  and  6  oz.  silver. 
The  rich  ore  in  the  Sulphide  vein  is  not  nowadays 
sent  to  the  smelter  but  is  treated  on  the  spot.  There 
is  nothing  in  the  report  to  bear  out  the  gloomy  pro- 
phesy of  a  year  ago,  which  pointed  to  a  diminution  in 
the  grade  of  the  ore  and  to  a  reduction  in  tiie  amount 
raised  due  to  difficulties  in  connection  with  the  shafts. 
Kerr  Lake. — This  company  owns  a  silver  mine  in 
the  southeastern  part  of  Cobalt  district,  Canada.  The 
control  is  with  the  Lewissohns,  and  John  Seward  is 
manager.  The  first  profits  were  made  in  1905.  The 
report  now  issued  covers  the  year  ended  August  31. 
and  shows  that  the  estimated  content  of  the  ore  mined 
was  2,388,420  oz.  of  silver.  The  ore  shipments  were 
as  follows  :  481  tons  of  high  grade  averaging  3577  oz. 
per  ton  ;  1270  tons  of  second  quality  averaging  362  oz.  ; 
30^  tons  of  jig  concentrate  averaging  92S  oz.  ;  and  154 
tons  of  slime  averaging  75  oz.  ;  in  addition,  metallics 
and  dump  material  were  sold  containing  12,964  oz. 
and  34,534  oz.  respectively  ;  a  total  estimated  content 
of  2,269,680  oz.  The  gross  receipts  were  8.1,231,245. 
against  which  #52,449  was  charged  for  treatment  and 
freight,  #232,083  for  mining  expenses,  and  #9334  for 
administration,  leaving  a  net  profit  of  #937.379.  The 
disidends  distributed  during  the  year  amounted  to 
#1,200,000,  bringing  the  total  to  date  #3,330,000. 
During  the  year,  the  sorting  tables  have  been  im- 
pro\ed  so  as  to  reduce  the  number  of  men  employed, 
and  jigs  have  been  introduced.  The  tailing  from  the 
jigs  and  the  finer  screening  from  the  sorting  tables  are 


396 


THE    MINING    MAGAZINE 


sold  to  the  Nova  Scotia  Mining  Co.  for  treatment.  An 
increased  amount  of  development  work  has  been  done 
this  year,  and  six  new  veins  have  been  discovered,  all 
promising  to  be  important  producers.  Owing  to  the 
difficulty  of  making  estimates,  no  figures  relating  to 
ore  reserves  are  given. 

Camp  Bird.— This  company,   as  we   have   already 
several  times  recorded,  was  floated  in  London  in  1900 
by  F.  W.  Baker  and  J.  H.  Hammond  to  acquire  from 
T.  F.  Walsh  the  gold  mine  of  that  name  in  Ouray 
county,  Colorado.     On  the  approaching  exhaustion  of 
the  mine,  the  Santa  Gertrudis  silver  mine  at  Pachuca, 
Mexico,  was  bought  two  years  ago.     The  purchase 
was  effected  by  the  payment  of  cash  out  of  reserve  and 
issuing  debentures,  and  with  the  capital  so  subscribed 
acquiring  nearly  the  whole  of  the  shares  of  the  Santa 
Gertrudis    company.     The  report  now  issued  covers 
the  year  ended  April  30.     It  shows  that  the  amount  of 
ore  discovered  during  the  year  was  very  small,  the  ore 
reserve  standing  on  April  30  at  38,415  tons,  as  com- 
pared with  83,900  tons  the  year  before,  in  the  mean- 
time 79,186  tons  having  been  extracted  and  sent  to  the 
mill.     The  yield  was  $1,685,979  in  gold,  or  $2289  per 
ton,  silver  worth  $71,435,  copper  worth  $8408,  and 
lead  worth  $46,748,  a  total  of  $1,812,571.     The  re- 
covery of  the  gold  content  was  just  under  95%.     Of 
the  total  extraction  of  metals,  64'32%  was  obtained  by 
amalgamation,  2881%  in  the  concentrate,  and  687% 
by    cyanidation.     The   concentrate    was    sold  to    the 
American  Smelting  &  Refining  Co.     The  total  income 
atthemineduringtheyearwas/372,696,or;^4.  14s.  Id. 
per  ton,  and  the  expenses  /153,262,  or  /I    18s.  8d.  per 
ton,  leaving  a  profit  to  be  carried  forward  to  profit  and 
loss  account  of  /219,434,  or  £2.  15s.  5d.  per  ton.  The 
accounts  are  credited  also  with  ;f83,691,  the  par  value 
of  vendors'  commission  shares  in  Santa  Gertrudis,  and 
are  debited  with  ;^30,000  inteiest  on  debentures  and 
;fl5,248  income  tax.     The  dividends  paid  during  the 
year  have  amounted  to  /220,002,  being  at  the  rate  of 
20%.     The  total  dividends  distributed  to  date  have 
been  /1, 505, 002.     Since  the  close  of  the  company's 
financial  year,  the  debentures  have  been  retired  and 
preference  shares  substituted  in  their  place.    Informa- 
tion relating  to  the  Santa  Gertrudis  company  is  given 
in  the  succeeding  paragraph. 

Santa  Gertrudis. — As  recorded  in  the  previous  para- 
graph thiscompany  was  formed  by  the  Camp  Bird  com- 
pany in  January  1909.  The  report  now  issued  shows  that 
the  past  eighteen  months  have  been  occupied  in  pre- 
paring the  mine  and  mill  for  the  contemplated  greatly 
increased  scale  of  operations.     To  protect  the   avio 
interests,    separate   companies  have  been  formed   in 
Mexico  to  do  the  mining  and  the  beneficiation  of  the 
ores.     Many  improvements  have  been    made  in  the 
shafts  and  their  equipments,  and  in  particular  the  old 
San  Guillermo  shaft  has  been  repaired  and  made  the 
main  hauling  shaft  with  a  capacity  of  1000  tons  per 
day.     An  advantageous  contract  has  been  made  with 
the  Mexican  Light  &  Power  Co.  for  the  supply  of  elec- 
tric power.     The  new  mill  was  ready  for  work  on  June 
14  last.     It  consists  of  60  stamps  of  1550  lb.  each,  10 
tube-mills,  18  Pachuca  vats,  Merrill  slime-filters.  Dorr 
thickeners  and  classifiers,  etc.     'W.  J.  Cox,  the  con- 
sulting engineer,  and  Hugh  Rose,  the  manager,  report 
that  the  developments  have  greatly  added  to  the  ore 
reserve,  the  figures  now  being  630,000  tons  of  proved 
ore   estimated  to  yield  a  profit    of   $4,610,000,    and 
520,000  tons  of  probable  ore  estimated  to  yield  a  pro- 
fit of  $3,565,000,  or  a  total  of  $8,175,000  or  nearly 
/1,700,00C.     In  January  last,  225,000  new  shares  were 
created,  and  of  these  93,000  have  been  issued  for  cash 
to  the  Camp  Bird  company. 


Natomas  Consolidated. — This  company  was  or- 
ganized under  the  laws  of  the  State  of  California  in 
November  1908  for  the  purpose  of  acquiring  the  pro- 
perties of  the  Natoma  Land  &  Mining  Co.,  the 
Folsom  Development  Co.,  and  the  Feather  River 
Development  Co.,  all  large  operators  of  gold  dredges 
in  the  Sacramento  valley.  The  issued  capital  is 
$14,617,300  in  shares,  and  $14,865,000  in  6%  mort- 
gage bonds.  In  the  spring  of  1910,  five  million  dollars 
worth  of  the  bonds  were  offered  in  London  by  the 
Hirsch  Syndicate,  the  prospectus  being  based  on  a  re- 
port made  by  C.  M.  Rolker.  Another  report  by  Mr. 
Rolker  has  now  been  issued,  dated  September  18  of 
this  year.  He  shows  that,  of  the  11  dredges  taken  over 
by  the  consolidated  company,  2  have  been  scrapped, 
that  a  new  hull  is  being  built  for  Folsom  No.  4,  and 
that  the  plan  of  providing  5  new  dredges  with  13|  cu. 
ft.  buckets  is  in  hand,  two  having  been  commissioned 
in  February  and  August  of  this  year  and  another  about 
to  start  at  the  time  of  writing  the  report.  Another  is 
to  be  ready  in  the  spring  and  the  fifth  at  the  end  of 
next  year.  The  combined  capacity  of  all  14  dredges 
will  be  nearly  28  million  cubic  yards  per  year.  During 
the  18  months,  January  1909  to  June  191 1 ,  the  yardage 
treated  was  44,542,141  and  the  recovery  $1,377,000; 
the  cost  was  $1,841,463,  and  the  dredging  profit 
$2,535,537.  The  figures  per  cubic  yard  were  :  yield 
9'95c.,  cost  4  08c.,  and  profit  5  87c.  The  tested  land 
contained  a  reserve  on  July  1  of  298,453,395  cu.  yd., 
with  a  possible  recovery  of  $29,715,195,  and  a  profit 
of  $17,531,657.  The  company  also  owns  other  ground 
only  partly  tested. 

Jumbo. — This  gold  mine  is  situated  in  the  Mazoe 
valley,  north  of  Salisbury,  Rhodesia,  and  has  been 
producing  since  1906  without  paying  a  dividend.  The 
controllers  are  the  United  Rhodesia  Gold  Fields,  and 
the  consulting  engineer  is  H.  A.  Piper,  of  the  Consoli- 
dated Gold  Fields  of  South  Africa.  The  report  now 
issued  covers  the  year  ended  June  30,  and  discloses 
the  unfortunate  fact  that  the  lower  levels  of  the  mine 
are  poor.  No  additional  ore  was  found  during  the 
last  nine  months  of  the  year  under  review,  and  the 
ore  sent  to  the  mill  has  been  of  lower  grade.  The  30 
stamps  treated  40,490  tons,  the  largest  yearly  amount 
yet  recorded,  and  the  yield  by  amalgamation  and  cya- 
nide was  worth  /67,209,  as  compared  with  ;^85,437 
the  year  before.  The  working  cost  in  Rhodesia  and 
London  was  ;^47,630  ;  in  addition,  /12,815  has  been 
written  off  for  depreciation,  and  /10,122  allowed  for 
redemption  of  mine  development.  The  ore  reserve 
stands  at  30,803  tons  estimated  to  average  9'81  dwt. 
In  the  old  part  of  the  mine,  nothing  is  left  but  the 
pillars,  and  these  are  now  being  extracted.  Mr.  Piper 
recommends  that  prospecting  should  be  continued  be- 
low the  7th  level  ;  while  he  is  not  particularly  hope- 
ful, he  reminds  shareholders  that  similar  critical  con- 
ditions have  been  experienced  before,  and  that  the 
life  of  the  mine  has  been  renewed  by  perseverance  in 
development. 

Caucasus  Copper. — This  company  was  formed  in 
1900  to  acquire  a  low-grade  copper  property  at  Dzansul 
in  the  Russian  Caucasus.  The  ore  is  plentiful  but 
difficult  to  concentrate,  and  its  beneficiation  has  given 
a  great  deal  of  trouble.  .\t  first,  direct  smelting  was 
tried,  but  had  to  be  abandoned,  as  too  much  flux  was 
required.  Then  magnetic  separation  was  tried,  with 
equally  disappointing  results.  Finally,  three  years  ago, 
James  Colquhoun,  who  used  to  be  manager  of  the 
Arizona  Copper  Co  ,  was  asked  to  join  the  board,  and 
to  advise  as  to  treatment.  Under  his  direction,  water 
concentration  has  been  tried  once  more,  and  sufficiently 
good  results  have  been  obtained.     The  plant  can  treat 


NOVEMBER,    1911 


397 


500  tons  per  day,  and  the  smelter  capacity  is  200  tons 
of  copper  per  month.  The  concentration  plant  is  to 
be  increased  so  as  to  bring  the  daily  amount  of  ore  to 
750  tons.  This  scheme  would  have  been  completed 
before  now,  but  for  the  severity  of  the  weather  during 
last  winter,  when  snow-storms  and  land-slides  cut  off 
communications  and  wrecked  the  pipe-line  through 
which  oil-fuel  is  delivered  to  the  mine  and  smelter. 
The  report  and  balance  sheet  for  the  year  ended  May 
31  does  not  therefore  show  the  position  of  the  com- 
pany to  have  improved  since  this  time  last  year,  when 
we  gave  in  our  issue  of  November  1910  an  outline  of 
the  operations.  In  fact,  the  company  has  not  yet  ar- 
rived in  a  position  when  it  is  able,  under  Russian  regu- 
lations, to  issue  a  profit  and  loss  account.  During  the 
year  1947  tons  of  copper  was  produced,  as  compared 
with  1140  tons  the  year  before,  but  still  500  tons  less 
than  should  be  possible  with  the  present  unextended 
concentration  plant.  The  profit  from  the  sale  of  the 
copper  is  stated  to  have  been  ;^25,600,  against  which 
;^23, 500  has  been  written  off  for  depreciation.  This 
profit  does  not  take  into  account  London  expenses 
and  interest  on  debentures  and  loans,  amounting  in  all 
to  /67, 100,  or  the  expenditure  on  new  plant  and  stores, 
which  was  as  much  as  ;^37,600.  The  indebtedness  of 
the  company  has  therefore  increased  during  the  year 
by  o\er  /lOO.OOO.  The  capital  of  the  company  is 
;f  500,000.  and  there  are  ;^635,600  debentures,  /534,900 
loans,  and  ;^42,740  accrued  interest  on  debentures  and 
loans.  A  number  of  high-class  mercantile  firms  in 
London  are  financially  interested,  the  J.  P.  Morgan 
group  being  probably  the  heaviest  involved.  W.  R. 
Van  Liew  is  now  general  manager,  having  previously 
been  chief  metallurgist. 

Chinese  Engineering  &  Mining. — This  company 
was  formed  in  1900  by  Bewick,  Moreing  &  Co.  to  ac- 
quire from  Chinese  owners  through  H.  C  Hoover  the 
collieries  of  Tong-shan  and  Lin-si  at  Kaiping  near 
Pekin  in  Northern  China.  Ihe  report  now  issued 
covers  the  year  ended  February  28  last  and  shows  that 
the  gross  profit  was  ;f  192,592.  The  administrative 
expenses  were  /10,263  ;  /25,700  was  paid  as  interest 
on  debentures,  ;^10,000  in  redemption  of  debentures, 
and  /35,000  was  placed  to  reserve  for  depreciation. 
The  net  profit  was  ;f  112,207,  out  of  which  /100,000 
has  been  distributed  as  dividend,  being  at  the  rate  of 


10' 


In  May  it  was  found  desirable  to  make  an  issue 


of  second  debentures  to  the  amount  of  /50,000,  being 
part  of  /250,000  authorized.  An  unfavourable  situa- 
tion is  caused  by  the  competition  of  the  adjoining 
Lan-chow  collieries,  and  it  has  been  found  necessary 
to  cut  prices.  On  the  other  hand  the  cost  of  mining 
has  been  substantially  reduced.  Efforts  are  being 
made  to  stop  the  competition  by  making  an  agreement 
with  the  Lan-chow  collieries  and  eventually  of  amal- 
gamating the  two  companies,  but  so  far  without  avail. 
A  proposal  to  erect  coke  ovens  and  sulphate  of  am- 
monia plant  is  under  consideration. 

Consolidated  Main  Reef. — This  mine  is  one  of  the 
Neumann  group,  and  is  situated  in  the  middle  west  of 
the  Rand.  Milling  started  at  the  beginning  of  1898, 
and  dividends  were  first  paid  in  1907.  The  report 
now  issued  shows  that  the  profits  have  increased,  and 
that  the  underground  conditions  have  improved.  The 
ore  raised  was  296,537  tons,  and  the  amount  sent  to 
the  mill  was  252,485  tons.  The  percentage  of  waste 
removed  by  sorting  was  only  15%,  as  compared  with 
23%  a  year  ago,  so  that  more  ore  was  sent  to  the  mill. 
It  has  been  possible  to  make  this  alteration  in  policy, 
partly  because  of  the  increase  in  the  number  of  tube- 
mills,  and  partly  because  the  average  grade  of  the  ore 
has  been  higher.     The  extraction  was  62,214  oz.  by 


amalgamation  and  23,877  oz.  by  cyanide,  a  total  of 
86,091  oz.,  or  68  dwt.  per  ton  milled,  as  compared 
with  63  dwt.  a  year  ago.  The  revenue  from  the  sale 
of  gold  was  ;f360,211,  or  28s.  6d.  per  ton  milled,  and 
the  cost  £212,211  or  21s.  6d.  per  ton,  leaving  a  profit 
of /87, 974,  or  6s.  lid.  per  ton;  /80,881  was  distri- 
buted as  dividend  at  the  rate  of  8j%.  Last  year  the 
profit  per  ton  milled  was  6s.  2d.,  the  tonnage  being 
only  235,391,  the  total  profit  £12,515,  and  the  divi- 
dend /69,372,  or  7^%.  A  sum  totalling  /86,631  was 
spent  on  machinery  and  shaft-sinking  out  of  capital 
subscribed  two  years  ago  for  the  purpose  of  extending 


EASTERN 

CHINA 


■OR  M  OS  A 


Boundanei 

Sca/e  of  >f;/tf5 


115 


/IS 


operations.  The  unexpended  balance  of  this  capital 
stands  at  /221,000.  Over  24,000  ft.  of  development 
work  was  done  during  the  year.  The  reserve  has 
been  increased  by  102,740  tons,  at  the  same  time  the 
content  increasing  by  04  dwt.,  the  figures  on  June  30 
being  516,890  tons  averaging  67  dwt.  over  42  inches. 
The  reports  by  S.  C.  Thomson,  the  consulting  en- 
gineer, and  C.  H.  Spencer,  general  manager,  also 
show  that,  by  the  increase  in  the  tube-milling  plant, 
the  extraction  has  been  raised  from  90  to  93%,  and 
that  the  new  vertical  shaft  to  strike  the  Main  Reef 
Leader  at  2500  ft.  is  down  823  ft. 

Main  Reef  West. — This  mine  also  belongs  to  the 
Neumann  group  and  is  situated  immediately  to  the 
west  of  the  Consolidated  Main  Reef.     S.  C.  Thomson 


398 


THE    MINING    MAGAZINE 


andC.  H.  Spencer  are  consulting  engineer  and  general 
manager  respectively  of  the  two  mines.  Milling  started 
in  1909  with  80  stamps,  and  in  1910  40  more  were 
added.  At  the  beginning  of  February  of  this  year  3 
tube-mills  were  put  into  commission.  Unfortunately 
the  underground  hauling  and  raising  arrangements 
have  not  proceeded  as  rapidly  as  the  surface  work,  so 
that  there  is  not  sufficient  ore  yet  being  hoisted  to 
keep  the  stamps  and  tube-mills  running  for  more  than 
18  days  per  month.  The  report  for  the  year  ended 
June  30  last  shows  that  13,739  ft.  of  development 
work  was  done,  of  which  1910  ft  was  shaft-sinking. 
The  ore  reserve  was  increased  by  nearly  200,000  tons, 
the  figures  on  June  30  being  628,260  tons,  averaging 
7  dwt.  The  content  has  been  decreased  as  compared 
with  a  year  ago  by  the  inclusion  of  several  blocks  in 
which  the  Main  Reef  and  the  Leader  can  be  mined 
together.  During  the  year,  231,608  tons  was  raised, 
and,  after  the  removal  of  15%  waste,  196,391  tons 
went  to  the  stamps.  The  production  was  56,693  oz. 
by  amalgamation  and  24,306  oz.  by  cyanide,  a  total  of 
80,999  oz.  or  8^  dwt.  per  ton.  The  revenue  from  the 
sale  of  gold  was  /338.797  or  34s.  6d.  per  ton  milled, 
the  cost  was  /198,924  or  20s.  3d.  per  ton,  and  the 
profit  /139,873  or  14s.  3d.  per  ton.  In  addition 
/96,732  was  spent  out  of  capital  on  the  shafts,  etc. 
The  dividend  absorbed  /101,250,  being  at  the  rate  of 
22|%.  It  is  expected  by  the  end  of  1911  that  the 
West  shaft,  which  was  2075  ft.  deep  in  August,  will  be 
equipped  sufficiently  to  make  it  possible  to  raise  more 
ore. 

New  Modderfontein. — This  mine  is  situated  in  the 
far  east  Rand  and  belongs  to  the  Rand  Mines  group. 
H.  Stuart  Martin  is  consulting  engineer.  Operations 
commenced  in  1896  with  40  stamps,  and  in  1909  the 
plant  was  increased  to  180  stamps  and  5  tube-mills. 
Early  this  year  a  Butters  filter  plant  was  added,  bring- 
ing the  monthly  capacity  of  the  plant  to  52,500  tons. 
The  haulage  plant  is,  however,  not  quite  ready  for 
this  rate  of  output.  The  report  now  issued  covers  the 
year  ended  June  30  and  is  highly  favourable.  Develop- 
ment work  has  increased  the  reserve  by  760,000  tons 
and  by  |dwt.  in  content,  the  figures  on  June  30  being 
3,452,195  tons  averaging  76  dwt.  The  rise  is  due 
to  the  increased  amount  of  high  grade  ore  found  in 
the  eastern  part  of  the  mine.  During  the  year,  600,976 
tons  was  raised  and,  after  the  removal  of  10%  waste, 
538,400  tons  went  to  the  battery.  The  recovery  by 
amalgamation  was  145,233  oz.  and  by  cyanide  43,437 
oz.,  a  total  of  188,670  oz.  The  yield  per  ton  milled 
was  7  dwt.  and  the  percentage  of  extraction  was  97% . 
The  gold  was  worth  ;^791,623,  or  29s.  5d.  per  ton 
milled,  an  increase  of  2s.  lOd.  per  ton  as  compared 
with  the  preceding  year.  The  working  cost  was 
/465,548  or  17s.  4d.  per  ton,  leaving  a  profit  of 
2326,074  or  12s.  Id.  per  ton.  Taxes  absorbed  £32,064 
and  ;i{^21,637  was  placed  to  the  account  of  capital  ex- 
penditure. The  dividends  absorbed  ;^297,500,  being 
at  the  rate  of  21^%,  as  compared  with  /165,000  for 
the  previous  year.  It  will  be  remembered  that  18 
months  ago  ^550, 000  of  new  capital  was  subscribed 
for  the  purpose  of  developing  the  mine  on  a  larger 
scale,  providing  new  reduction  plant,  and  electrifying 
the  machinery.  During  the  year  /222,000  has  been 
spent  in  this  way.  The  new  main  circular  shaft,  18  ft. 
in  diameter,  is  down  425  ft. 

Consolidated  Gold  Fields  of  South  Africa. —  The 
annual  report  of  this  South  African  corporation  for 
the  year  ended  June  30  shows  that  the  net  profit  was 
/792,883,  as  compared  with  /993,381  a  year  ago,  and 
^■l, 283, 851  the  year  previous.  Out  of  this.  /100,000 
has  been  written  off  the  value  of  shares  in  producing 


mines,  so  as  to  provide  against  their  exhaustion  ;  the 
figure  compares  with  ^200, 000  a  year  ago  and  ;^500,000 
the  year  before.  The  dividend  on  the  ordinary  shares 
is  /600,000  or  30%,  as  compared  with  35%  last  year. 
During  the  year  the  6%  preference  shares  have  been 
increased  from  /1, 250, 000  to  /2, 500, 000,  in  order  to 
provide  funds  for  the  expansion  of  the  company's  busi- 
ness outside  the  Transvaal,  especially  in  America,  and 
the  debenture  issue  has  been  reduced  by  ;^25,000  to 
^225,000.  The  reserve  fund  remains  at  ;^2,000.000, 
half  of  which  is  invested  in  the  company's  business 
and  half  in  gilt-edged  securities.  The  report  records 
the  failure  of  the  Simmer  East,  the  acquisition  of 
claims  from  the  Booysen  Estate  adjoining  the  Robin- 
son Deep,  the  formation  of  a  subsidiary  to  handle 
Rhodesian  interests,  and  another  to  manage  the  Ameri- 
can business.  The  prospects  of  success  in  West  Africa 
are  discussed,  and  the  necessity  for  a  reduction  in  cost 
is  emphasized  ;  with  this  object,  the  government  of 
the  Gold  Coast  colony  is  asked  to  assist  in  recruiting 
cheap  labour.  The  reports  of  the  engineers,  C.  D. 
Leslie  and  H.  A.  Piper,  describe  the  progress  on  the 
Rand  and  in  Rhodesia.  The  reports  of  the  various 
mines  belonging  to  the  group,  Simmer,  Robinson 
Deep,  Knights  Deep,  Simmer  Deep,  and  Jupiter  are 
made  up  on  July  31,  a  month  later  than  that  of  the 
parent  company,  so  they  are  not  available  for  our 
present  issue 

TRADE    NOTES 

Most  of  the  trade  publications  mentioned  in  this 
column  are  available  for  distribution  and  the 
manager  of ''The  Mining  Magazine"  will  be 
pleased  to  secure  copies  for  persons  interested. 

The  Dorr  Cyanide  Machinery  Company's  London 
office  is  at  17  South  Street,  South  Place,  London, 
E.G.  Mr.  William  Russell  is  the  special  represen- 
tative. 

The  Merton  Furnace  Co.  report  the  shipment  of  a 
Merton  roaster  to  the  Whim  Well  copper  mine  in 
West  Australia;  by  its  means  hematite  will  be  re- 
duced to  magnetite  which  is  required  in  connection 
with  the  Murex  concentration  process. 

The  British  Humboldt  Engineering  Co.,  Ltd.,  ad- 
vise us  that  the  Mawchi  Tin  &  Wolfram  Mines,  Ltd., 
have  recently  placed  an  order  for  a  complete  magnetic 
separating  plant  for  the  Mawchi  Co.'s  mines  in  India. 
The  plant  is  sectionalized,  so  that  the  gross  weight  of 
the  heaviest  individual  part  does  not  exceed  400  lb. 
The  plant  can  thus  be  transported  on  elephants'  backs 
to  the  company's  mine^  situated  about  20  miles  from 
Pazaung  in  the  Karenni  State,  India. 

Chester's  Renfrew  Engineering  Co.,  Ltd.,  announce 
the  purchase  of  the  works  of  Edward  Chester  &  Co., 
Ltd.,  at  Renfrew,  Scotland.  The  existing  plant  has 
been  enlarged  and  modernized,  and  the  new  company 
is  in  a  position  to  quote  prompt  delivery  and  reason- 
able prices  for  engines,  compressors,  water  -  tube 
boilers  and  mining    machinery  of  every  description. 

The  Sandycroft  Foundry  Co.  have  just  completed 
a  large  winding  engine  driven  by  steam  power  to  be 
erected  at  the  new  vertical  circular  shaft  of  the  Cham- 
pion Reef  gold  mine  in  India.  The  horse-power  is 
5500,  and  it  will  raise  15^  tons  at  the  rate  of  3000  ft. 
per  minute  from  a  depth  of  3700  ft.  There  are  two 
cylinders,  one  at  each  end  of  the  drum,  42  in  diam. 
and  84  in.  stroke,  fitted  with  Corliss  gear.  The  drum 
is  cylindrical  with  conical  ends  ;  the  maximum  dia- 
meter is  20  ft.  and  the  length  14  ft.  6  in.  A  Gott  con- 
trolling gear  is  provided  for  preventing  over-speed, 
over- winding,  and  starting  in  the  wrong  direction. 


m 


The  Mining  Magazine 


Vol.  V. 


LONDON,  DECEMBER   1911 


No.  6 


Scientta   non   habet   inimicum   nisi   ignorantem. 


T.   A.    RICKARD,    Editor.  EDGAR    RICKARD,    Business  Manager. 

PUBLISHED  BY  THE  MINING  PUBLICATIONS  LTD.,  at  819  SALISBURY  HOUSE.  LONDON.  EC 

Issued    on    the    15th    day    of   each    month. 

Telegraphic  Address :    Oligoclase.     Codes  :  MciVej7/,  both  editions.     Telephone:    8938   London    Wall. 

Branch  Offices  • 
SAN  FRANCISCO:  420  MARKET  STREET.     CHICAGO:  734  MONADNOCK  BUILDING.      NEW  YORK:  29  BROAD  WAV 

Agents  for  the  Colonies  : 

GORDON    &    GOTCH,    LONDON,    MELBOURNE,    Etc.    (SOUTH    AFRICA:    CENTRAL    NEWS    AGENCY.    LTD.) 

Registered  with  the  G.P.O.  for  transmission  to  Canada  by  Canadian  Magazine  Post. 


SUBSCRIPTION    RATES. 

United  Kingdom  and  Canada,  12  Shillings  (Single  Copy,  Is.)    ...    Abroad,  16  Shillings  (Single  Copy,  Is.  4d.) 


C  O  N  T  E  N    r  S. 


Review  of  Mining. 


PAGE 

401 


PAGE 

400 


Editorial 

Notes 407 

Emmons  Memorial 410 

Eileen  Alannah 410 

East  Rand  Proprietary 412 

Basic  Lining  for  Converters 413 

Loose  Reporting 414 

The  Copper  Queen 415 

The  Finance  of  a  Mine 417 

Seasonal  Variations 418 

Secretaries 419 

A  Fundamental  Factor 420 

Special  Correspondence 

J  ohannesburg 42 1 

Camborne 424 

San  Francisco 425 

Mexico 426 

Melbourne 428 

Toronto^ 429 

New  York 430 

Articles 

Mining  in  Madagascar T. Draper  439 

The  Finance  of  a  Mine.  VI 

M.  H.  Burnham  444 

The  Blackwater  Mine 

Harold  Sliarpley  448 

Mining  on  the  Coast  of  British  Colum- 
bia  Percy  Williams  449 

Oil  Industry  of  Roumania 

R.  C.  N.  Twite  453 

Mine  Sampling S.  F.  Shaw  457 


Statistics  of  Production 

Metal  Markets 432 

Personal 438 

Discussion 

Sampling  L.  W.  Strauss  433 

Cyanidation  v.  Concentration 

G.  A.  Denny  433 

Standardization  in  Assays 

H.  T.  Durrant  434 

A  Miner's  Protest Ralph  Stokes  435 

Casapalca  Smelter  .Lester  W.  Strauss  436 
Estimates  of  Extraction  /.  F.  Couttct  436 
Ball- Mill  Practice.. .Do//aW  F.  Foster  437 

Precis  of  Technology 

Tin  in  German  Southwest  Africa 461 

Diamonds  in  British  Columbia 4b  1 

Ores  in  Sandstone  and  Shale 461 

The  Nissen  Stamp  in  South  .\frica  ...  462 
Marketing  Copper  in  the  Ignited  States  464 

A  Strange  Mineral 464 

The  Standard  Tin  Contract 4t)4 

Cyaniding  Concentrate  at  Treadwell...  464 
Electrolyti'^  Assay  of  Gold  Solution  ...  465 
Determining  the  Quality  of  Lime  ..•••   466 

Concentration  at  Cobalt 466 

The  Clancy  Process  466 

Current  Literature 467 

Books  Reviewed 468 

Company  Reports 469 

Trade  Notes  476 


400 


THE    MINING    MAGAZINE 


STATISTICS 

Stocks  of  Copper  in  England  and  the  Continent. 
Reported  by  Henry  R.  Merton  &  Co. 


Production  of  Gold  in  Rhodesia. 


Sept.  30 
Tons 

Oct.  31 
Tons 

Nov.  30. 
Tons 

52,111 
5,654 
2,375 
7,200 

48.357 
5.704 
2.075 
5,900 

+4,597 

5,485 

2,250 

Afloat  from  Australia 

6,350 

Xotal                      

67,340 

7,250 

11,100 

61.836 

6.900 

10.200 

58,682 

5,700 

In  Hamburg  (estimated)... 

8,900 

American  Copper  Producers'  Association. 
In  Tons  of  2,240  lb.  


Produc- 
tion. 


January  1911 51,650 

February    49,030 

March 58,273 

April 52,716 

May 56,679 

June 55,605 

July  50,075 

August 56,024 

September 51,602 

October 52,792 

November 49.945 


18,785 
22,553 
29,500 
23,396 
28,814 
27,525 
25,438 
26,757 
25,587 
28,602 
30.375 


23,753 
20,139 
26,375 
27,736 
27,669 
31,902 
33,429 
31,185 
22,689 
26,832 
29,932 


42,538 
42.692 
55,875 
51,132 
56,483 
59,427 
58,867 
57,942 
48,276 
55.425 
60,307 


Stocks  at 
end  of 
month 


63,591 
69.929 

72,325 
73.909 
74,105 
70.283 
61,491 
59.573 
62,899 
60.267 
49,905 


Production  of  Gold  in  the  Transvaal. 


Rand 


Totals.  1910., 

January  1911 

February  

March 

April  

May    

June    

July 

August  

September  

October 

November 


Oz. 

7,228,588 

625,862 
585,683 
649,247 
638,421 
658,196 
657,023 
679,881 
682,405 
669,773 
677,923 
691,462 


hlse- 
where 

Oz. 

305,532 

25,201 
24,965 
26,818 
29,293 
27,755 
27,544 
29,377 
31.002 
30.852 
30.7J1 
28.267 


Total 

Oz. 

7,534,120 

651,027 
610,828 
676.065 
667,714 
685,951 
684,567 
709,258 
713,407 
700,625 
708.644 
719,729 


Value 

£ 

32,002,912 

2.765,386 
2,594,634 
2,871,740 
2836,267 
2,913,734 
2,913,734 
3,012,738 
3,030,360 
2,976,065 
3.010,130 
3,057.213 


Cost  and  Profit  on  the  Rand. 


Month. 


January  1911. 

February 

March  

April 

May 

June  

July   

August 

September.... 
October   


Tons 


!    Yield 
per  ton 


1.865,232 
1,712,198 
1,960.678 
1,926,583 
2,002,926 
1,986,559 
2,095,220 
2,107,809 
2,037,329 
2.083.S00 


s. 
26 

28 
28 

27 
27 


Costs  ■    Profit 
per  ton   per  ton 


d. 
11 

3 
11 

6 
10 


s. 
10 
10 

9 
10 

9 


Total 
profit 


27    6 

17  11 

9     8 

27    2 

17  10 

9    4 

26    8 

17    9 

8  11 

27     4 

1«     1 

9     4 

27     0 

18    0 

9     1 

£ 

930.059 
874,612 
949,415 
971,858 
956.823 
960,381 
969,687 
967,457 
952,665 
948.278 


Natives  Employed  in  the  Transvaal  Mines. 


January  31.... 
February  28... 

March  31  

.\pril  30 

May  31  

June  30 

July  31 

.'\ugust  31 

September  30 
October  31  .. 
November    .. 


Gold 
mines 


183,268 
189,434 
193,457 
194,328 
190,392 
186,940 
181,582 
179,810 
179,619 
179,194 
176.736 


Coal 
mines 


8,357 
8,513 
8,493 
8.511 
8,379 
8,212 
8,122 
8,182 
8,045 
8,078 
8.013 


Diamond 
mines 


Total 


9,991 
9,814 
10,061 
10,272 
10,425 
10,597 
11,054 
11,292 
11,475 
11.319 
10.071 


201.616 
207.761 
212.011 
213,111 
209,196 
205,749 
200.758 
199,284 
199,139 
198,591 
194.850 


Gold  Output  of  India. 

Year  1909 

Year  1910 
£2,104,858 

Nov.   1911 

1911  to  date 

£2,083,901 

£186,225 

£1,781.876 

Month. 


1908 


1909 


January 

February  ... 

March   

April  

May 

June 

July 

August  

September 

October 

November- ■ 
Decembe^•• 

Totals  . 


£ 

199,388 
191,635 
200,615 
212,935 
223,867 
224,920 
228,151 
230,792 
204,262 
205,466 
196,668 
217,316 


£ 

204,666 
192,497 
202,157 
222,700 
225,032 
217,600 
225,234 
228,296 
213,249 
222,653 
236,307 
233,397 


1910 


1911 


2,526,007    2,623,788 


£ 

227,511 
203.888 
228,385 
228,213 
224,888 
214,709 
195,233 
191,423 
178,950 
234,928 
240,573 
199.500 


£ 

207,903 

203.055 
231.947 
221,296 
211,413 
215,347 
237.517 
243,712 
225.777 
218,862 


2,568,201 


Production  of  Gold  in  West  Africa. 


Month. 


1909 


Oz.       Value 


January  ... 
February 

March 

April    

May 

June 

July  

August  

September 
October  ... 
November 
December 


22,817 
21,403 
23,186 
21,491 
25,104 
17,340 
17,331 
17,766 
18,125 
15.957 
17,882 
17.570 


£ 
91,112 
86,210 
93.556 
88,071 
100,056 
70,561 
70,523 
71,614 
72.963 
65,813 
73,824 
71.332 


1910 


Oz. 


17,357 
16,976 
17,627 
16.363 
16,590 
17,194 
15,564 
13,921 
11,497 
13,341 
14,021 
15,042 


Value 


£ 

70,699 
68,469 
71,954 
67,069 
68,355 
70,988 
58,551 
57,713 
47,746 
55,046 
57,658 
61.737 


1911 


Oz. 


Value 


15.903 
15,179 
16,387 
17,237 
24,427 
22,555 
22,510 
25,385 
26,717 
26,826 


235,972   1055,635    185,493    755,985  — 


£ 
66.107 
63.081 
67,673 
70.880 
96,409 
92,174 
91.955 
103,753 
109,039 
109,503 


Production  of  Gold  in  Western  Australia. 


Month. 

Export 
oz. 

Mint 
oz. 

Total 
oz. 

Total 
value 

Total,  1910  

363,496 

1,209,856 

1.573.352 

£ 

6,682,042 

January  1911  

17,463   '      102.035         119.498 

507,592 

22.047 
12,296 

84,991 

93,267 

91.791 

88,952 

106,464 

97,387 

102,477 

114,615 

106,733 

107,038 
105.563 
112,246 
111,028 
116,987 
112.721 
113,993 
119,626 
117,397 

454,666 

March                       

448,426 

20,455 
22,076 
10,523 
15.334 
11,521 
5,011 
10.664 

476,787 

May              

471,615 

497,188 

Tuiv                    

478,805 

484,168 

508,135 

October      

498,668 

November 

9.762 

108,646 

118,408 

502,962 

Other  Australasian  Gold  Production. 


Queensland 

New  South  Wales 
New  Zealand. 


1909 


£ 

1,916,468 

869.546 

2.006.910 


Victoria |    2,897,340 


1910 

£ 

1,840,337 

803,727 

1,896.322 

2,422,700 


I  November 
'        1911 

£ 

i  141.350 
40,851 
142,512 
179,985' 


1911 
to  date 


£ 

1,479.110 

689,220 

1,678,127 

1.770,107* 


*  October  figures  only. 
Sale  of  Tin  Concentrate  at  Redruth  Ticketings. 


Tons 

Value 

Average 

SeDtember  4     1911 

220 

2491 

224| 

251 

2354 

248J 

232j 

£25,262 
£27,170 
£25,221 
£28,342 
£27,176 
£28,274 
£27,385 

£ll4  16    8 

September  18.   ..     

£108  15    9 

Ortnhf^r    0                    

£112    4    4 

October  16, 

£112  19     1 

October  SO                       

£115     8    0 

£113  17  11 

November  27,    „     

£117  18    3 

E.XPORTS  OF  Tin  and  Ore  from  Straits  and  Bolivia. 
Reported  by  A.  Strauss  &  Co. 


Metal  from  Straits  to  Europe 
and  America   ! 

Metallic  Content  from  Bolivia' 
to  Europe 


Oct.  1911 
tons 

4.385 

1.947 


Nov.  1911 
tons 

5.045 

1.363 


1911  to  date 
tons 

49.370 

20.657 


REVIEW    OF    MINING 


Introductory.  —  Political  events  have 
continued  to  affect  the  share  markets.  Sir 
Edward  Grey's  speech  on  November  27,  ex- 
plaining British  policy,  was  deemed  pacific 
but  it  was  not  followed  by  any  notable  increase 
of  speculation.  Paris  has  been  selling  South 
African  shares,  being  much  depressed  by  the 
East  Rand  fiasco.  A  committee  has  been 
formed  with  a  view  to  protecting  French 
holders  of  Transvaal  shares.  The  report  of 
the  East  Rand  commission  of  inquiry  has 
made  a  profound  impression.  Incidentally  it 
accentuates  the  objection  to  registration    of 


for  1911  will  be  worth  ;^35,000,000,  as  against 
i:31,995,266  in  1910.  The  labour  returns  ex- 
hibit a  decrease  of  425,  the  total  number  of 
natives  employed  on  gold  mines  being  179,194, 
as  against  180,103  in  the  corresponding  month 
of  last  year.  However,  a  year  ago  the  decrease 
in  October  was  2097  and  in  November  it  was 
2076,  so  there  is  a  chance  of  improvement. 
On  the  other  hand,  some  600  additional  stamps 
are  now  at  work  ;  so  that  the  demand  for  labour 
has  grown  while  the  supply  is  no  better. 

Mr.    H.    O'K.    Webber,    president  of  the 
Chamber  of  Mines,  stated  recently  that  the 


companies  in  the  Transvaal  so  long  as  they      number  of  '  boys' returning  to  their  kraals  has 


look  for  financial  support  in  Europe.  Ob- 
viously there  is  lack  of  control.  Regrettable 
as  are  the  recent  exposures  of  mismanage- 
ment, as  at  the  Prestea  and  East  Rand,  it 
is  well  that  the  real  facts  should  be  recognized 
and  that  those  who  find  the  money  for  mining 
enterprise  should  protest  against  the  irrespon- 
sibility exhibited  by  their  trustees  on  the  direc- 
torates. Despite  some  adverse  factors  the 
general  trend  of  the  market  is  toward  a  re- 
covery of  cheerfulness  and  activity.  Copper 
consumption  is  improving.  Legislation  in 
America  is  less  of  a  menace  to  capitalized  in- 
dustry. Political  developments  in  Europe  are 
not  so  perturbing.  Dividends  are  accumu- 
lating. An  increase  of  speculation  is  probable 
in  the  near  future. 

Transvaal. — The  golc  and  labour  statistics 
for  October  were  not  remarkable  ;  if  anything, 
they  were  disappointing.  This  is  due  mainly 
to  the  decrease  from  the  Witwatersrand  Deep 
mine,  which  was  troubled  by  water.  The 
output  of  708,644  ounces,  worth  /■3,010,130, 
has  only  been  exceeded  in  July  and  August, 
but  the  rate  of  production  per  diem  was  less 
than  in  September.  With  two  more  monthly 
returns  at  about  the  same  rate  the  production 


been  larger  than  usual,  but  it  was  hoped  that 
by  June  next  the  supply  of  labour  would  show 
an  increase  for  the  year.  Recruiting  in  Por- 
tuguese territory  is  proceeding  as  usual  but  in 
British  South  Africa  the  supply  of  foodstuffs 
is  so  good  as  to  encourage  idleness  among  the 
natives.  Competition  for  labour  from  farming 
and  other  industries  is  being  keenly  felt  by  the 
mining  companies.  It  is  hoped  that  the  Union 
Government  will  exercise  paternal  interest  in 
the  subject  and  investigate  the  causes  under- 
lying the  acknowledged  shortage  of  labour  at 
Johannesburg. 

We  note  with  interest  that  Messrs.  Lewis 
and  Marks,  the  South  African  operators,  have 
incorporated  their  successful  business  in  the 
style  of  Lewis  and  Marks,  Ltd.,  in  a  company 
having  an  issued  capital  of  /"l, 500, 000.  In 
addition  to  Messrs.  Isaac  Lewis,  Barnet 
Lewis,  and  Samuel  Marks,  the  present  part- 
ners, the  directorate  will  include  Mr.  C.  F. 
Rowsell,  who  has  long  held  the  signature  of 
the  firm  and  is  chairman  of  many  companies. 

The  City  Deep  has  been  the  victim  of  ad- 
verse rumours  for  several  weeks,  first  in  re- 
gard to  defects  in  the  mill,  and  then  with 
reference  to  the  titles  of  its  mining  claims. 


401 


402 


THE    MINING    MAGAZINE 


Undoubtedly  some  basis  does  exist  for  the 
belief  that  the  new  mill  has  not  given  satis- 
faction. We  are  informed  that  the  use  of  re- 
inforced concrete  in  the  kingposts  has  proved 
a  mistake.  The  adoption  of  the  Nissen  stamp 
was  announced  so  soon  after  the  mill  had  been 
erected  as  to  warrant  the  belief  that  the  plant 
was  not  doing  as  well  as  had  been  expected. 
As  to  titles,  the  official  denial  of  any  defect 
must  be  accepted.  The  output  of  the  mine  is 
increasing  and  the  cost  is  being  decreased,  but 
the  full  capacity  of  the  plant  willnot  be  reached 
until  next  summer. 

The  Modderfontein  B  announces  excellent 
results  for  November,  31,025  tons  yielding 
12,214  ounces.  The  working  cost  is  18s.  6d. 
and  the  profit  14s.  6d.  The  total  profit  is 
given  as  /^22,497,  but  the  real  figure  is  about 
;^30,000,  no  less  than  2559  oz.  having  been 
put  to  reserve.  This  is  done  because  the  yield 
is  above  the  average  of  the  mine. 

The  Cinderella  Consolidated  has  effected 
a  connection  underground  on  the  3000- ft. 
level  with  the  Cason  shaft,  so  that  it  now 
has  two  outlets.  It  will  be  remembered  that 
the  Cinderella  Deep  vertical  shaft  cut  the 
banket  in  the  early  part  of  1906  at  4003  feet 
and  that  sinking  was  continued  to  4123  feet) 
so  as  to  allow  space  for  ore-bins.  The  main  in- 
cline shaft  was  started  at  3900  feet  and  has  now 
reached  a  depth  of  1000  feet  on  the  incline. 

Rhodesia. — The  gold  output  in  October 
was  only  51,974  ounces  valued  at  ^^218,862, 
which  is  the  lowest  yield  since  June.  No  de- 
claration is  made  by  the  Claremont,  Matabele 
Queen,  and  Surprise  mines.  As  usual,  the 
official  statistics  are  incomplete,  some  com- 
panies giving  their  output  in  ounces,  others  in 
pounds  sterling  ;  the  supposed  profit  is  not  cal- 
culated on  a  uniform  basis,  some  excluding 
essential  items  of  expense.  The  productive 
mines  number  162,  but  24  of  them  produced 
70%  of  the  total  gold. 

The  announcement  of  a  further  decrease  in 
the  supply  of  native   labour  in  Rhodesia  is 


accompanied  by  the  statement  that  the  Cham- 
ber of  Mines  has  decided  that  the  minimum 
rate  of  wages  offered  on  recruiting  shall  be 
increased  33%  for  surface  labourers  and  10% 
for  those  working  underground.  Even  this  in- 
crease will  not  bring  the  rate  up  to  that  of  the 
Rand,  but  it  may  stimulate  employment. 

The  cablegram  informing  the  shareholders 
in  the  Surprise  that  the  so-called  '  reef  '  cut  at 
130  feet  is  "  poor  but  solid  "  adds  a  final  touch 
of  humour  to  a  serio-comic  mining  enterprise. 
The  solid  "  quartz  assays  I  pennyweight  per 
ton.  It  might  be  useful  for  manufacturing 
ginger-beer  bottles  for  Rhodesians  hampered 
by  a  noble  thirst.  It  is  a  curious  survival  of 
'  true  fissure  '  days  to  imagine  that  a  "  solid  " 
quartz  vein  is  more  deserving  of  economic 
respect  than  an  ill  defined  lode  consisting  of 
country-rock  impregnated  with  quartz  and 
more  valuable  minerals.  Great  men  spring 
from  "  poor  but  honest "  parents,  but  great 
mines  do  not  spring  from  poor  but  solid  veins 
of  hungry  quartz. 

The  resignation  of  Dr.  Hans  Sauer  from  the 
directorates  of  a  number  of  companies  is  a 
noteworthy  event,  but  one  that  is  not  calcu- 
lated to  injure  the  prestige  of  the  Rhodesian 
mining  industry.  We  hope  it  may  synchronize 
with  a  policy  more  considerate  to  the  rights  of 
shareholders  and  better  designed  to  win  public 
confidence. 

Announcement  is  made  of  negotiations  with 
a  view  to  the  transfer  of  the  Rhodesian  Ex- 
ploration &  Development  Co.  to  the  control 
of  the  Consolidated  Gold  Fields  of  South 
Africa  by  absorption  into  its  subsidiary,  the 
Gold  Fields  Rhodesian  Development  Co. 
Owing  to  recent  disclosures  it  is  likely  that 
the  change  will  receive  public  approval,  but 
it  will  need  more  than  this  or  any  other 
manipulation  of  interests  to  win  public  confi- 
dence. Greater  regard  must  be  shown  for  the 
rights  of  shareholders,  by  prompt  and  frank 
reports,  not  the  belated  and  cryptic  statements 
that  now  pass  as  information. 


DECEMBER,    1911 


403 


West  Africa.— The  October  statistics  are 
satisfactory,  showing  the  largest  gold  produc- 
tion as  yet  recorded,  namely,  26,826  ounces, 
valued  at  ^109,503.  The  total  for  the  ten 
months  of  the  current  year  is  213,126  oz.,  as 
compared  with  200,520  oz.  in  the  first  ten 
months  of  1909,  Not  much  reason  exists 
for  congratulation,  but  at  least  less  cause  for 
depression  may  be  discovered,  seeing  that 
in  1910  the  comparative  total  was  156,430 
ounces.  Among  the  outputs  of  individual 
mines,  that  of  the  Ancobra  Dredging  Co.  is 
noteworthy,  the  output  having  doubled  as 
compared  to  any  recent  month.  The  Prestea 
exhibits  a  decrease,  from  ^■23,778  to  ir20,132. 
The  Ashanti  Goldfields  maintains  its  premier 
position,' with  an  output  worth  ;^41,422.  The 
Broomassie,  Abosso,  and  Taquah  mines  hold 
their  own. 

The  Taquah  Central  has  struck  a  new  lode 
of  goldbearing  banket  in  a  cross-cut  from  the 
main  shaft.  It  is  a  friable  ore  and  gives  pro- 
mising assays.  Further  cross-cuts  will  be  ex- 
tended to  intersect  this  lode  from  the  present 
bottom  level.  The  Fanti  Syndicate  publishes 
most  satisfactory  assays  of  samples  broken  in 
two  prospecting  shafts.  Three  feet  of  25  to  30 
dwt.  ore  is  recorded.  The  West  ^African  Trust 
has  secured  an  option  for  two  years  on  the  pro- 
perties of  the  Sefwi  Goldfields.  An  experi- 
mental plant  will  be  erected  to  test  the  ore  as 
development  progresses.  A  belated  cablegram 
from  the  Prestea  announced  that  the  output 
for  November  would  be  cut  down  to  10,000 
tons  of  ore,  owing  to  pipe-laying  in  the  Ap- 
pantoo  shaft. 

At  the  Ashanti  Goldfields,  the  exploration 
of  the  Obuasi  shoot  on  the  8th  level  from  the 
main  shaft  continues  to  give  good  results.  At 
100  ft.  nearer  to  the  main  shaft  than  the  de- 
velopment reported  last  month,  a  cross-cut  has 
disclosed  a  width  c^^  15  ft.  of  ore  averaging 
15  dwt.   per  ton. 

Monthly  statistics  of  production  are  pub- 
lished to  indicate  the  work  being  done  by  the 
6—2 


Nigerian  tin  mines,  but  these  statistics  are 
nearly  worthless,  and  probably  misleading, 
since  no  uniform  unit  is  employed.  The  '  tin  ' 
is  in  the  form  of  a  concentrate  of  variable  com- 
position, which  is  not  stated,  so  that  no  basis 
of  comparison  exists. 

Australasia.— The  October  returns  from 
the  Associated  denote  decided  improvement, 
the  profit  increasing  from  3s.  Id.  to  7s.  4d.  per 
ton.  The  Golden  Horse-Shoe  and  Persever- 
ance both  retrograded.  The  Oroya  Links 
shows  the  improvement  due  to  greater  ton- 
nage.   The  New  Zealand  group  is  doing  well. 

The  report  of  the  West  Australian  Depart- 
ment of  Mines  for  1910  has  just  been  issued. 
It  is  belated,  as  is  usual  with  such  official 
statistics,  but  it  contains  some  interesting  in- 
formation. For  instance,  the  working  cost  is 
higher,  largely  on  account  of  the  harder  rock 
penetrated  by  the  deeper  workings.  But  this 
is  slight  relatively  to  the  great  decrease  in 
yield,  from  an  average  of  77s.  per  ton  in  1903 
to  42s.  in  1910.  This  is  accompanied  by  a 
proportionately  lower  profit,  from  18s.  in  1903 
to  7s.  per  ton  in  1910.  A  pathetic  touch  is 
to  be  detected  in  reference  to  Bullfinch,  it 
being  stated  that  "  the  rich  discoveries  in  the 
Yilgarn  field  had  caused  a  boom,  with  resultant 
inflow  of  capital,  which  it  is  sincerely  hoped 
will  have  happy  results."  It  may  be  sincerely 
hoped,  but  it  cannot  be  intelligently  expected. 
Capital,  like  water,  can  be  easily  spilled,  but 
is  recovered  with  difficulty  when  once  it  has 
irrigated  a  barren  enterprise. 

The  Great  Cobar  meeting  passed  quietly. 
Disappointment  over  results  was  explained  as 
being  due  to  labour  troubles,  which  have  hin- 
dered other  Australian  companies.  Another 
reason  is  the  neglected  development  of  the 
parent  mine,  it  being  apparent  that  metallur- 
gical problems  have  diverted  too  much  atten- 
tion from  systematic  operations  underground. 
Finally,  the  purchase  of  the  Cobar  gold  mine 
has  involved  delay  and  expense  by  reason  of 
the  need  to  put  it  also  into  satisfactory  shape. 


404 


THE     MINING     MAGAZINE 


We  note  with  pleasure  that  Mr.  W.  Pellew- 
Harvey  has  been  elected  a  director.  He  was 
a  moving  spirit  in  the  Cobar  gold  mine,  and 
his  presence  on  the  board  of  the  Great  Cobar 
will  be  an  element  of  strength. 

The  Mt.  Lyell  strike,  in  Tasmania,  was 
ended,  by  a  provisional  agreement,  on  No- 
vember 12.  A  conference  is  to  meet  shortly 
with  a  view  to  considering  an  increase  of 
wages.  Both  parties  appear  willing  to  make 
reasonable  concessions.  The  Golden  Horse- 
Shoe  strike  is  also  ended.  Labour  trouble, 
due  to  the  union  having  prohibited  work  on 
contract,  has  disorganized  operations  at  the 
Ida  H.  mine,  also  in  Western  Australia.  This 
has  led  to  the  passing  of  the  dividend,  but 
better  conditions  are  anticipated. 

The  transfer  of  the  Oroya  Exploration 
holdings  to  the  Lake  View  Consols,  with  the 
absorption  of  the  Black  Range  by  the  Yuanmi 
company,  has  been  endorsed  by  the  sharehold- 
ers. This  will  give  the  Lake  View  a  diversified 
and  scattered  interest  in  mining  enterprises 
and  consolidate  the  power  of  an  able  group, 
led  by  Messrs.  H.  C.  Hoover  and  F.  A. 
Govett. 

The  Einasleigh  copper  mine  in  North 
Queensland  is  to  be  purchased  by  the  Chil- 
lagoe  company,  the  payment  being  made  by 
175,000  new  shares  of  10s.  each.  For  two  or 
three  years  the  copper  and  lead  mines  in  the 
Chillagoe  neighbourhood  have  been  yielding 
less  ore  than  formerly  and  the  Chillagoe  com- 
pany's smelter  has  been  short  of  supplies. 
The  Einasleigh  mine,  about  175  miles  south, 
on  the  Etheridge  railway,  has  been  one  of  the 
smelter's  chief  sources  of  copper  ore  during 
the  last  year.  The  consolidation  of  interests 
will  be  in  favour  of  shareholders  in  both  com- 
panies. 

We  note  with  approval  that  the  managers 
of  the  Great  Fitzroy  have  cut  down  their  esti- 
mate of  ore  in  reserve  owing  to  the  necessity 
for  leaving  pillars  to  support  the  workings. 
Such  pillars  may  subsequently   be  recovered, 


but  it  is  unlikely  that  all  of  them  will  be  avail- 
able for  the  mill.  The  latest  news  in  regard 
to  the  metallurgical  work  is  more  encouraging, 
the  extraction  having  been  raised  to  82%  cop- 
per and  76%  gold.  If  this  is  confirmed  by 
further  work  it  will  constitute  a  notable  sue 
cess  for  the  oil-flotation  process.  The  trouble 
hitherto  appears  to  have  been  a  large  propor- 
tion of  impurities  in  solution,  now  overcome 
by  softening  the  water  with  lime. 

The  west  lode  has  been  cut  on  the  14th 
level  of  the  Sons  of  Gwalia.  This  ore-shoot 
has  now  been  traced  from  the  surface  to  the 
14th  level.  It  averages  10  to  12  dwt.  per  ton 
for  a  width  of  10  to  12  feet,  for  a  maximum 
length,  so  far  proved,  of  300  feet.  It  consti- 
tutes one  out  of  several  supplementary  ore- 
bodies  in  this  mine.  The  recent  assays  from 
the  bottom  of  the  Great  Fingall  are  not  so 
good.  The  maximum  length  of  the  new  ore- 
body  is  430  feet,  on  the  17th  level,  where  it 
averages  about  10  dwt.  per  ton. 

India. — The  final  dividend  of  the  Cham- 
pion Reef  for  the  year  ended  September  30 
brought  the  total  distribution  to  43i%,  as  com- 
pared with  23^^%  for  the  previous  year  ;  this 
is  the  highest  dividend  since  1907,  when  the 
workings  came  into  the  poor  zone.  The  mine 
continues  to  develop  well  in  depth,  though  the 
average  grade  is  much  lower  than  in  the  old 
palmy  days.  The  chief  factors  in  the  increase 
of  profit  have  been  the  reduction  in  working 
cost  and  a  slight  rise  in  the  content  of  the  ore 
treated.  The  Dharwar  group  of  mines  has 
finally  been  abandoned,  owing  to  the  poor  re- 
sults obtained  below  ground  and  also  in  the 
metallurgical  plant.  It  will  be  remembered 
that  eighteen  months  ago  the  Dharwar  Reefs 
company  was  reconstructed  as  the  Kabulgitti 
Co.,  with  the  object  of  continuing  develop- 
ment and  providing  a  modified  plant  for  treat- 
ing the  accumulated  tailing,  but  as  only  a 
limited  number  of  shares  were  subscribed  the 
mine  was  not  re-opened  and  operations  were 
centred  on  the    metallurgical    treatment.      It 


DECEMBER,    1911 


405 


was  known  that  the  graphitic  content  was 
against  easy  extraction,  and  all  sorts  of  me- 
thods were  tried  with  the  object  of  minimizing 
its  effect.  Unfortunately  no  method  has  been 
devised  that  was  cheap  enough.  The  plant 
and  the  property  are  therefore  to  be  aban- 
doned. 

United  States. — Dredging  for  gold  in 
Cahfornia  is  an  expanding  industry.  The 
official  statistics  for  1910  are  available  and 
show  that  the  total  gold  produced  by  dredging 
was  $7,550,254.  Yuba  county  is  credited 
with  $3,172,476,  an  increase  of  $730,557  as 
compared  with  1909  :  Butte  gave  $2,389,235, 


the  company  and  giving  it  a  new  reserve  of 
ore,  besides  possibilities  of  development,  on 
most  reasonable  terms. 

An  embittered  litigation  has  been  started 
between  the  Golden  Cycle  and  Christmas 
mining  companies  at  Cripple  Creek  over  ore 
in  disputed  ground  and  other  matters.  This 
has  been  anticipated  by  the  distribution  of 
profits  by  the  Christmas  in  the  shape  of  a 
dividend  of  70  cents  per  share,  amounting  to 
$1,050,000.  Mr.  John  T.  Milhken  is  the 
central  figure  in  this  imbrogHo. 

An  important  scheme  has  been  placed  be- 
fore the  shareholders  of  the  Arizona  Copper 


A   STOPE    THAT   CAVED   IN    THE   ARIZONA    COPPER   CO.'S  MINE   AT  MORENCE. 

a   decrease    of   $501,038;    Sacramento  gave  Co.,  the  headquarters  of  which  are  in  Edin- 

$1,369,594,    also    a    decrease    of    $164,542.  burgh,  involving  the  extension  of  the  concen- 

Among  individual  companies  the  Yuba  Con-  trating  plant  and  the  re-building  of  the  smel- 

solidated  contributed    $2,927,246,    the   yield  ter,  the  object  being  to  permit  of  the  benefi- 

being  20-88  cents  per  cubic  yard  and  the  cost  ciation   of  large  deposits  of  low-grade  ore. 

5-67  cents.  TheNatomas  worked  9-64c.  gravel  Oil-fired  reverberatories  are  to  be  adopted, 

at  a  cost  of  4-52  cents  per  cubic  yard.  the  heat  of  the  gases  being  utilized  further 

We  tell  the  story  of  the  Tomboy  elsewhere,  for  the  production  of  electric  power.     The 

The  recent  annual  meeting  was  rendered  im-  output  of  ore  will  be  increased  from  750,000 

portant  by   the   information    concerning    the  to  1,000,000  tons  per  annum,  and  of  copper 

purchase  of  additional  property,  covering  the  from  15,000  to  20,000  tons.     The  saving  in 

extension  of  the  Argentine  lode.     Apparently  cost   is   estimated  at   ^200,000  per   annum, 

the  transaction   is   highly  favourable  to  the  equal  to  a  reduction  of  2  cents  per  pound. 

Tomboy  shareholders,  prolonging  the  life  of  The  scheme  has  been  prepared  by  Mr.  L.  D. 


406 


THE    MINING    MAGAZINE 


Ricketts,  and  is  endorsed  by  the  former  man- 
ager, Mr.  James  Colquhoun.  The  capital  ex- 
penditure involved  will  be  ;^450,000  and  the 
money  is  to  be  raised  by  the  issue  of  termin- 
able debentures.  Mr.  Ricketts  estimates  that 
the  known  reserve  of  ore  will  yield  200,000 
tons  of  copper,  and  that  development  will  re- 
veal substantial  continuations  of  the  orebodies. 

Referring  to  British  interest  in  the  Ply- 
mouth mine,  on  the  Mother  Lode,  California, 
it  is  interesting  to  note  that  a  neighbouring 
property,  the  old  Kennedy,  has  struck  speci- 
men ore.  This  mine  is  3970  feet  on  the  dip 
and  3550  feet  vertical. 

James  B.  Grant  died  on  November  2.  As 
one  of  the  founders  of  the  Omaha  &  Grant 
Smelting  &  Refining  Co.,  subsequently  a  part 
of  the  combination  known  as  the  American 
Smelting  &  Refining  Co.,  he  played  an  im- 
portant part  in  metallurgical  affairs,  especially 
in  Colorado.  He  was  at  one  time  the  Governor 
of  that  State  and  took  a  useful  share  in  all 
public  movements.  As  a  young  graduate  from 
Freiberg  he  went  to  Leadville  and  started  one 
of  the  first  smelters  in  that  locality,  exhibiting 
the  shrewdness  and  energy  that  made  him  so 
successful,  until  he  became  absorbed  in  share 
speculation.  His  kindly  personality  will  be 
missed  among  a  large  circle  of  friends  and  his 
demise  marks  the  closing  of  an  era  during 
which  the  Colorado  smelters  dominated  min- 
ing in  the  Rocky  Mountain  region. 

Canada. — Our  Toronto  correspondent  sends 
the  latest  Porcupine  and  Cobalt  news.  The 
Temiskaming  Mining  Co.  of  Cobalt,  by  Mr. 
Burr  Cartwright,  the  president,  has  bought  the 
138,000  shares  of  North  Dome  held  by  P. 
Kirkegaard  for  $170  per  share. 

Siberia. — The  Kyshtim  is  now  the  largest 
producer  of  copper  in  Russia.  Large  sums  of 
money  are  being  spent  in  further  expansion  of 
operations  and  equipment  of  plant.  The  output 
forthe  currentyear  will  be  about  5000  tons, and 
next  year  it  ought  to  be  fully  6500  tons  of 
copper.     This  is  being  produced  at  a  cost  of 


^30  per  ton,  as  against  a  market  price  in 
Russia  of  £^5,  the  import  duty  making  the 
price  ;^25.  10s.  more  than  the  standard  Lon- 
don rate.  The  refinery  extracts  ;^10  worth 
of  gold  from  each  ton  of  metallic  copper. 

The  Atbasar  issues  a  good  annual  report, 
of  which  the  most  interesting  portion  is  Mr. 
R.  Oilman  Brown's  estimate  of  the  resources 
of  the  property.  He  considers  that  389,000 
tons  of  ore  has  been  proved,  representing  a 
gross  value  of  over  ;^3,000,000.  As  yet  only 
a  small  part  of  the  company's  territory  has 
been  tested.  A  smelting  plant  to  produce  5000 
tons  of  copper  per  annum  is  to  be  erected. 

Spain. — For  the  last  year  the  Pena  Copper 
Mines  company  has  been  harassed  with  liti- 
gation instituted  by  the  Rio  Tinto  company 
with  regard  to  alleged  unfair  cutting  of  prices 
for  pyrite  in  contravention  of  the  agreement 
whereby  the  Rio  Tinto  railway  carries  the 
Pena  products  to  port.  The  Rio  Tinto  com- 
pany has  repeatedly  been  beaten  in  the  Courts. 
In  order  to  be  free  from  this  transport  trouble, 
the  Pena  company  has  agreed  with  the  Spanish 
Government  to  finance  the  construction  of  a 
branch  line  connecting  with  a  different  line  of 
railway  to  the  coast.  For  the  purpose  of 
raising  the  necessary  capital,  the  shareholders 
of  the  Pena  company  agreed  last  month  to 
subscribe  for  150,000  new  shares  of  £\  each. 

Various. — Shortage  of  labour  is  reported 
by  the  Ouro  Preto,  in  Brazil.  However,  it  is  not 
acute,  judging  from  the  excellent  work  done 
during  the  past  year.  Extraction  of  gold  from 
the  ore  has  improved  from  91*87  to  92T5  per 
cent. 

Ferrobamba  affairs  are  developing.  Tests 
made  by  Mr.  Claude  Vautin  prove  that  the 
oxidized  ore  and  the  bornite  ore  can  both  be 
concentrated  when  treated  separately,  and  that 
the  mixed  product  will  then  represent  a  con- 
centration of  11  :  1,  containing  30%  copper, 
and  suitable  for  reverberatory  smelting.  The 
American  group,  headed  by  Mr.  A.  C.  Bur- 
rage,  has  now  got  60?^  of  the  shares. 


EDITORIAL 


w 


'HEN  PUBLISHING  reports  giving 
the  opinions  and  recommendations  of 
their  mine  manager  or  consulting  engineer,  it 
is  advisable  for  mining  companies  to  state  the 


A' 


MONG  the  anomalies  of  mine  adminis- 
tration may  be  mentioned  the  signing 
of  reports,  as  consulting  engineers,  by  land, 
finance,  or  exploration  companies.   The  value 


name  of  the  engineer.     Upon  the  reputation      of  a  report  depends  upon  the  man  who  makes 


of  the  man  himself  depends  the  value  of  his 
professional  opinion.  Personal  responsibility 
is  essential  to  mine  reports. 


EAST  RAND  affairs  prove  for  the  nth 
time  that  technical  practice  suffers  by 
the  use  of  wrong  terms.  Rock  that  cannot 
be  exploited  profitably  is  waste.  No  good 
comes  from  describing  it  as  "  ore  below  the 
officially-accepted  pay  limit."  Not  only  share- 
holders, but  managers  also,  are  confused  by 
the  constant  employment  of  terms  that  lead 
inevitably  to  unscientific  modes  of  thinking. 
The  entire  subject  of  Rand  economics  is 
brought  to  the  verge  of  absurdity  by  a  ter- 
minology that  is  unworthy  of  a  great  industry 
based  upon  the  application  of  technical  science. 


it,  and  when  a  report  is  signed  by  an  accoun- 
tant or  secretary  on  behalf  of  a  nondescript 
firm,  however  eminent  in  the  financial  world, 
then  such  a  report  is,  to  say  the  least,  not 
convincing.  Anyone  accepting  the  guidance 
afforded  by  an  opinion  on  a  mine  requires,  or 
should  require,  the  name  of  the  engineer  on 
whose  inspection  that  opinion  is  based.  We 
go  even  further  and  say  that  a  corporation  has 
no  sense  of  honour  such  as  may  be  expected 
of  the  individuals  in  that  corporation.  It  is 
the  personal  equation  that  eternally  affects  all 
calculations  of  success  on  the  part  of  a  min- 
ing, industrial,  or  any  other  sort  of  enter- 
prise. 


R 


ECENT  CHANGES  in  the  adminis- 
tration of  the  United  States  Geological 
Survey  are  noteworthy.  Mr.  C.  Willard 
Hayes,  chief  geologist,  under  the  director, 
Mr.  George  Otis  Smith,  resigned  to  accept  a 
position  as  advisory  geologist  to  S.  Pearson 
East  Dome  mine  at  Porcupine.  Needless  to  &  Son,  in  Mexico.  On  Mr.  Hayes' resigna- 
say  such  control  of  a  mine  is,  in  Mr.  Lawson's  tion  the  post  of  chief  geologist  was  offered  to 
case,  usually  accompanied  by  a  campaign  of      Mr.  Alfred  H.  Brooks,  who  has  special  charge 


DEPRESSION  in  the  mining  market 
may  shortly  be  mitigated,  for  it  is  an- 
nounced that  Mr.  Thomas  W.  Lawson,  of 
Boston,  has  acquired  control  of  the    Preston 


publicity  that  never  lacks  gaiety.  The  speci- 
men ore  found  in  Northern  Ontario  should 
afford  good  copy  for  his  tropical  imagination. 
The  recent  fire,  the  golden  sidewalk,  and  the 
hidden  assay-plans  should  all  yield  excellent 
material,  wherewith  the  exponent  of  the  Sys- 
tem can  weave  a  glittering  fabric  of  literary 
spoof.  We  are  in  the  dumps  in  London, 
and  therefore  anticipate  the  time  when  Mr. 
Lawson  will  give  copious  advertisements — to 
our  contemporaries. 


of  the  Alaskan  work  of  the  Survey  ;  but  the 
promotion  was  not  accepted  by  Mr.  Brooks. 
His  decision  to  stick  to  a  work  to  which  he 
has  devoted  himself  with  so  much  energy  and 
success  is  highly  creditable  to  him,  and  will, 
we  know,  be  cordially  appreciated  in  Alaska. 
For  ourselves,  having  an  intimate  acquaint- 
ance with  the  exploratory  and  geological 
labours  of  the  officers  of  tlie  U.S.  Geologi- 
cal Survey  in  Alaska,  we  take  the  opportunity 
again  to  emphasize  our  keen  appreciation  of 


407 


408 


THE    MINING    MAGAZINE 


the  valuable  service  rendered  by  this  scienti- 
fic branch  of  the  American  government  to  one 
of  the  most  interesting  mining  regions  of  the 
globe.     We  are  glad  indeed  that  the  chief  of 
that  division  of  the  Survey  has  decided   to 
forego  promotion  in  the  desire  to  continue  the 
work  so  well  begun.     It  remains  to  state  that 
Mr.  Waldemar  Lindgren  has  been  appointed 
chief  geologist  in  succession  to  Mr.  Hayes. 
This  is  an  excellent  appointment.     Mr.  Lind- 
gren has  been  on  the  Survey  since  1884  ;  for 
the  last  four  years  he  has  been  in  charge  of 
metal  statistics  and  the  investigation  of  metal- 
liferous deposits.     He  represents  the  modern 
school  of  geologists,  who  bring  a  more  thor- 
ough knowledge  of  physics  and  chemistry  to 
bear  upon  the  study  of  ore  deposits  than  was 
available  among  the  earlier  chiefs  of  the  Sur- 
vey.    Among  those  engaged   in  mining  Mr. 
Lindgren  is  known  not  only  for  a  series  of 
brilliant  studies  of  great  practical  importance, 
but  also  for  an  engaging  personality  that  is 
one  of  the  many  links  between  the  represen- 
tatives of  science  and  the  captains  of  industry. 


combined  with  the  possible  lack  of  real  know- 
ledge of  a  subject,  the  tendency  is  to  replace 
useful  criticism  with  wordy  compliment.    The 
highest  compliment  to  anauthor  is  serious  criti- 
cism. We  trust  that  Mr.  Coste  takes  this  view. 
He  replied  with  spirit,  but  became  entangled 
in  the  use  of  a  language  with  which  he  is  not 
as  familiar  as  with  his  native  tongue.     We 
hoped  for  a  moment  that  he  might  be  tempted 
to  use  French,  in  the  humorous  supposition 
that  all  his  listeners  understood  the  most  polite 
of  all  languages.     The  result  of  the  discussion 
is  some  entertainment,  some  elucidation  of  a 
complex  matter,  but  the  origin  of  oil  remains 
a  subject  for  further  enlightenment. 


DISCUSSION  of  a  lively   and  forceful 
character  marked  the  last  regular  meet- 
ing of  the   Institution.     The  origin  of  oil,  a 
subject  introduced  by  Mr.  Eugene  Coste  at 
the  previous  meeting,  was  the  topic  for  the 
occasion.     Sir  Thomas  Holland  delivered  a 
clever  and  useful  criticism,  enlivened  by  telling 
touches  of  satirical  humour,  and  based  on  facts 
collected  during  his  official  sojourn  in  India. 
Rarely  have  we  enjoyed  so  much  the  effective 
use  of  criticism  when  applied  to  pseudo-scien- 
tific matters.     Some  of  it,  when  read  in  cold 
print,  will  probably  seem  a  little  caustic,  but 
when  he  said  it  he  smiled.     He  was  followed 
by  Messrs.  T.  O.  Bosworthand  A.  Wade,  both 
of  whom  contributed  something  worth  while. 
Indeed  the  whole  discussion  reached  a  level 
unusual  at  the  Institution,  especially  in  mat- 
ters pertaining  to  economic  geology.     Amia- 
bility is  usually  carried  to  such  an  excess  that, 


SOME  WRITERS  to  the  technical  Press 
appear  to  be  unaware  of  one  or  two  points 
in  journalistic  etiquette,  and  it  may  be  advis- 
able to  refer  to    them    briefly.     Anonymous 
communications  cannot  be  printed ;   even    a 
pseudonym  must  be  accompanied  by  a  letter 
acknowledging    the    identity    of    the    writer. 
When  a  manuscript  is  submitted  for  publica- 
tion to  one  journal  it  must  not  be  oflfered  to 
another ;  until  a  reply  is  received   from  the 
first  editor  the  article  submitted  is  in  effect 
under  option  to  him.     A  miner  who  has  given 
an  option  on  his  claim  to  one  speculator  will 
not  give  another  option  to  another  speculator 
until  the  first  option  has  expired  or  has  been 
released.     A  manuscript  is  as  much  a  piece  of 
property  as  a  prospect-hole,  and  occasionally 
is  more  valuable.     If  a  writer  sends  a  copy  of 
his  article  to  more  than  one  journal  he  should 
notify  the  recipients,  who,  in  most  cases,  would 
not  then  care  to  publish  it,  unless  it  proved  of 
such  rare  interest  as  to  warrant  duplicate  pub- 
lication.    Permission  is  rarely  refused  to  the 
author  to  reprint  his  article  after  it  has  once 
appeared  in  print,  and  in  most  cases  the  editors 
of  technical  journals  will  lend  the  illustrative 
blocks  and  afford  other  facilities  for  doing  so. 
Apart  from  the  morality  of  giving  or  selling 
the  same  thing  to  two  persons,  the  duplicate 


DECEMBER,    1911 


409 


publication  of  a  technical  article  is  objection- 
able because  diverse  versions  thus  become 
available.  One  of  these  may  be  carefully 
edited  ;  the  other  may  be  an  unrevised  edition. 
If  the  article  should  prove  important  any  re- 
ferences to  it  in  technical  literature  would  be- 
come confused  by  the  existence  of  two  unlike 
versions. 


one  on  which  public  opinion  will  eventually 
insist  successfully. 


ATTENTION  has  been  focussed  on  the 
responsibiUties  of  directors  by  a  suit 
brought  by  a  shareholder  in  the  Trust  Com- 
pany of  the  Republic  against  two  directors, 
Messrs,  George  Gould  and  Herbert  Satterlee, 
for  the  recovery  of  sums  of  money  lost  by  the 
Trust  company  through  loans  made  to  the 
notorious  Shipyard  Trust  and  to  the  president 
of  the  Trust  Company  itself.  A  decision  by 
the  Supreme  Court  appears  to  take  a  lax  view 
of  the  responsibility  assumed  by  directors  and 
seems  to  approve  of  one  man,  for  instance, 
holding  40  directorates  at  the  same  time.  The 
Court  says  that  "  directors  generally  are  not 
supposed  to  have  a  knowledge  of  the  details 
of  the  business  management  of  the  corpora- 
tion which  are  not  submitted  to  them.  If 
they  are  compelled  to  supervise  the  details 
of  the  management  of  each  corporation  in 
which  they  are  directors,  or  if  they  are  deemed 
to  have  constructive  knowledge  of  such  facts 
as  would  be  acquired  by  such  supervision,  it 
would  be  wholly  impossible  for  them  to  accept 
such  a  trust,"  and  the  Court  holds  that  any- 
thing that  would  lead  to  the  loss  of  the  services 
of  such  men  would  be  "  little  less  than  calami- 
tous." We  are  declined  to  discount  the  cala- 
mity and  to  place  a  premium  on  a  keener  sense 
of  personal  responsibility.  It  is  manifestly 
impossible  for  any  man  to  exercise  efficient 
supervision  over  the  affairs  of  30  to  40  enter- 
prises. As  a  director  he  is  a  trustee  for  the 
shareholders,  to  whom  he  should  give  faithful 
service.  This  may  be  a  Utopian  view  of  the 
director's  function,  but  it  is  one  that  we  do  not 
despair  of  advocating,  believing  that  it  is  also 


THE  BATTLE  of  the  processes  has  been 
nowhere  waged  more  vigorously  than  in 
Colorado,  where  chlorination  and  cyanidation 
have  competed  with  varying  success  during 
two  decades  for  preference  in  the  treatment 
of  the  ores  of  Cripple  Creek.  Cyanidation  is 
the  victor,  for  it  has  been  apparent  for  several 
years  that  the  application  of  tube-milling  and 
cyanidation  to  the  tailing  from  the  chlorina- 
tion plants  had  placed  these  in  a  humiliating 
position.  Chlorination  became  a  triplex  pro- 
cess, involving  the  successive  application  of 
chlorine  gas,  concentrating  devices,  and  cya- 
nide solution.  Meanwhile  cyanidation  had 
evolved  as  a  direct  treatment,  after  roasting 
of  the  crude  ore.  For  a  long  time  the  big 
battalions  of  capital  were  on  the  side  of  chlori- 
nation, the  principal  plants  using  the  process 
being  consolidated  in  a  corporation  capitalized 
at  ;^2,500,000  and  known  as  the  United  States 
Reduction  &  Refining  Co.,  which  must  not  be 
confounded  with  the  smelter  trust,  called  the 
American  Smelting  &  Refining  Co.  or  its  chief 
rival,  the  United  States  Smelting,  Refining  & 
Mining  Co.  The  Standard  mill  at  Colorado 
Springs,  the  last  of  the  chlorination  plants, 
has  just  been  closed-down,  leaving  cyanida- 
tion in  undisputed  possession  of  the  field.  The 
Portland  Gold  Mining  Company  has  recently 
changed  its  mill  to  cyanidation  and  the  suc- 
cessful plant  at  Stratton's  Independence  is,  of 
course,  the  most  up-to-date  exponent  of  the 
cyanide  process.  The  mill  trust  has  now  four 
chlorination  mills  on  its  hands,  besides  a  plant 
for  using  zinc-fume  in  manufacturing  paint, 
all  of  which  are  idle.  These  originally  cost 
^■300,000,  or,  if  we  include  the  Metallic  Ex- 
traction plant,  about  ^400,000,  against  which 
stocks  and  bonds  were  issued  for  ;^2,500,000. 
No  assets  remain,  save  the  residue  discarded 
in  the  heyday  of  chlorination,  now  only  a 
memory. 


410 


THE    MINING    MAGAZINE 


THE  SERIES  of  articles  in  The  Times 
describing  the  copper  mining  and  smelt- 
ing enterprise  of  the  Tanganyika  Concessions 
affords  an  interesting  example  of  the  use  of 
newspaper  publicity.  But  it  appears  to  us 
extremely  maladroit.  At  the  head  of  each 
article  it  is  stated  in  italics  that  the  writer 
accompanied  Mr.  Robert  Williams  "  at  the 
suggestion  of  the  Advertisement  Department 
of  The  Times  "  and  that  "  the  expense  of  the 
publication  is  borne  by  the  Tanganyika  Con- 
cessions, Limited."  The  articles  are  un- 
signed and  therefore  of  no  technical  value, 
although  affording  an  interesting  outline  of 
an  enterprise  having  many  and  diversified 
features  ;  and  they  do  not  take  the  place  of  ac- 
tual information  concerning  the  present  posi- 
tion of  an  affair  in  which  so  much  money  has 
been  sunk.  These  articles,  however,  do  one 
thing,  which  we  recognize  with  pleasure.  They 
bring  out  the  fact  that  the  mineral  exploration 
and  commercial  development  of  Central  Africa 
owes  much  to  the  unbounded  energy  and  in- 
vincible optimism  of  Mr.  Robert  Williams. 
While  we  may  be  sceptical  as  to  the  success 
of  the  present  Tanganyika  undertaking,  we  do 
believe  that  the  great  orebody  in  the  Congo 
Free  State  will  eventually  become  the  basis 
for  a  large  and  profitable  enterprise,  and  that 
it  will  prove  a  pioneer  in  opening  up  a  large 
tract  of  African  territory.  Mr.  Williams  re- 
minds us  of  the  late  William  C.  Greene,  who 
started  the  Cananea  copper  enterprise,  and 
was  a  real  pioneer  of  industry  both  in  Arizona 
and  Mexico.  He  was  not  nearly  as  well  edu- 
cated a  man  as  Mr.  Williams,  indeed  he  was 
of  a  much  coarser  fibre,  but  he  was  like  him 
in  energy  and  persistence,  and  he  was  like  him 
in  one  fundamental  failing,  namely,  not  know- 
ing any  limit  to  his  scope,  so  that  he  under- 
took to  decide  technical  questions  for  which 
he  was  not  equipped,  and  therefore  avoided 
engaging  the  services  of  first-rate  technical 
men.  What  is  true  of  the  Greene-Cananea  is 
true  of  the  Williams-Tanganyika. 


Emmons  Memorial. 

A  committee  has  been  formed  by  some  of 
the  friends  of  the  late  S.  F.  Emmons  to  collect 
funds  with  a  view  to  creating  a  memorial,  to 
take  the  form  of  an  endowment  for  a  research 
fellowship  in  economic  geology  at  Columbia 
University.  The  treasurer  is  Mr.  B.  B.  Law- 
rence, at  60  Wall  Street,  New  York.  The 
statement  of  these  facts  should  be  enough  to 
prompt  contributions  in  support  of  so  worthy 
a  purpose.  Any  mining  engineer  who  is  ignor- 
ant of  the  great  service  done  to  geology  and 
to  mining  by  the  life-work  of  Emmons  is  not 
likely  to  be  impressed  by  anything  we  could 
say  ;  to  those  who  know,  any  panegyric  is 
supererogatory.  The  geological  record  con- 
tains the  names  of  greater  scientists  than 
Emmons,  but  it  contains  the  name  of  no 
man  who  did  so  much  to  apply  geology  to 
industry.  What  economic  geology  in  America 
especially,  and  also  in  its  worldwide  applica- 
tion, owes  to  him  would  be  expressed  by  a 
sum  of  money  large  enough  to  endow  a  great 
university.  It  is  not  desired  to  do  anything 
grandiose  but  to  create  a  useful  memorial  in 
a  university  honourably  prominent  as  an  ex- 
ponent of  technical  education  and  one  to  which 
Emmons  was  tied  by  many  silken  cords  of 
friendship.  We  commend  the  proposal  to 
our  readers.  Write  to  Mr.  Lawrence  and 
send  him  your  subscription. 


Eileen  Alannah. 

This  romantic  name  has  been  given  to  a 
flotation  of  which  it  may  be  said  that  it  illus- 
trates one,  at  least,  of  the  factors  that  have 
discredited  the  Rhodesian  mining  industry. 
The  prospectus  is  marked  by  an  optimism  in- 
consistent with  the  experience  of  gold  mining 
either  in  Africa  or  elsewhere.  The  reports 
are  by  two  engineers  of  acknowledged  repute, 
Messrs.  A.  H.  Ackermann  and  Leopold  Weill. 
It  appears  from  the  prospectus  that  the  mine 
is  capitalized  at  ;^500,000  in  £\  shares,  of 
which  250,000  are  allotted  to  the  vendors  in 


DECEMBER,    1911 


411 


part  payment  and  160,000  are  issued  at  22s. 
6d.  to  the  shareholders  of  three  affiliated  Rho- 
desian  companies.     Mr.  Weill  gives  no  esti- 
mate of  ore  in  reserve.     Mr.  Ackermann  esti- 
mates 148,229  tons  at  13*6  dwt.  gold  per  ton, 
which  on  the  assumption  of  an  85%  extraction 
and  a  working  cost  of  17s.  6d.,  will  leave  a 
profit  of  3  Is.  6d.  per  ton,  or  a  total  of  ^223,460. 
On  the  evidence  available  this  estimate  is  san- 
guine.    Some  of      the  blocks  cannot  be  de- 
scribed [so  says  Mr.  Ackermann  himself]  as 
fully   developed."     A  later   cablegram   from 
this  engineer  increases  the  estimated  reserve 
to   174,824  tons,  including   15,000   tons  pro- 
bable,  averaging   13'5  dwt.  per  ton,  so  that 
the  estimated  profit  is  raised  to  ;^262,000.    It 
is  acknowledged  that  the  ore  is  refractory  in 
depth  and   that  "  a  large  proportion    [of  the 
gold]    has  been  found  to  pass  away   in   the 
slime,"  hence  it  is  advised  that  the  mill  be 
shut-down   pending   further   development    of 
the  mine,  with  a  view  to  ascertaining  the  real 
character  of  the  ore  to  be  treated.    Obviously 
therefore  the  flotation  of  the  company  is  pre- 
mature.    But  we   question   whether   further 
work  in  the  mine  is  necessary  to  ascertain  the 
proper  method  of  treatment.     That  has  been 
done  by  the  Cam  &  Motor  management,  into 
whose  territory  the  Eileen  Alannah  lode  passes 
on  its  strike.     Moreover,  the  working  cost  of 
17s.  6d.  contrasts  with  23s,  given  by  the  engi- 
neers of  the  Cam  &  Motor.     The  higher  figure 
is  unlikely  to  be  the  less  accurate.     Again, 
experience  shows  that  only  about  80%  of  the 
working  '  profit '  at  a  mine  finally  reaches  the 
shareholder  in  the  shape  of  dividends.     This 
is  a  point  often  overlooked  by  engineers  and 
directors,   not  to  mention  the  simple    share- 
holders.    Let  the  reader   compare  the  total 
'  profits '  as  announced  by  the  mines  of  the 
Rand,  for  example,  with  the  dividends  paid 
in  the  same  year.     Thus  even  if  we  take  the 
;^262,000  of  estimated  profits,  we  must  make 
deductions  for  an  additional  cost  of  5s.  per  ton, 
at  least,  and  for  20%  that  is  absorbed  in  ex- 


penses that  do  not  appear  on  the  books  at  the 
mine.     In  other  words,  the  Eileen  Alannah, 
as  at  present   developed,  will   do  nobly  if  it 
yields  dividends,  not  illusory  profits  of  any 
kind,  but  real  money,  amounting  to  ^200,000. 
But  Mr.  Weill  estimates  that  "  an  outlay  of 
^140,000  will  be    sufficient    to  develop   the 
mine,  equip  it  with  suitable  reduction   plant, 
and  bring  it   to    the    producing  stage."     To 
erect   a   /"HO.OOO    plant    to  gain  ;^200,000, 
that  is,  to  treat  a  reserve  that  would  supply 
the  mill  for  30  months,  at  a  resulting  final 
profit    of  ^60,000,    is  manifestly  ridiculous. 
As   against    this    we    have    a    market   valu- 
ation, on  the  shares  issued,  of  ;^460,000.     It 
may  be  supposed  therefore  that  the  mine  has 
good  prospects  ;    in  other  words,  that  it  is  an 
expanding  enterprise.     Here  we  are  bound  to 
say  that  we  marvel  at  the  lack  of  acumen  ex- 
hibited by  the  promoters  in  issuing  a  longitu- 
dinal section  of  the  mine  which  shows  clearly 
that  the  length  of  profitable  ore  is  720  feet  on 
the  first  level  and  only  400  feet  on  the  fourth  ; 
it  shows  also  that  the  orebody  is  pitching  flatly 
into  the  adjoining  claim,  the  Good  Shepherd, 
which  belongs  to  the  Cam  &  Motor  company. 
At  the  same  pitch  the  orebody  will  probably 
have  passed  over  the  western  boundary  within 
400  feet.     This  feature  is  illustrated  on  the  so- 
called  '  block-plan,'  but  it  is  not  made  clear  in 
the  reports  of  Messrs.  Ackermann  and  Weill. 
It  is,  of  course,  vital  to  the  enterprise.     The 
drawing  that  is  supposed  to  show  the  distribu- 
tion of  ore  does  not  agree  with  statements  in 
Mr.  Ackermann's  report  and  apparently  was 
prepared  in  London,  for  it  purports  to  record 
information  contained  in  his  cablegram  of  Oc- 
tober 28.     Between  June  1  and  October  28, 
the  exploratory  work,  as  shown  on  the  map, 
includes  the  driving  of  an  aggregate  of  over 
1000  feet,  through  a  block  400  feet  long  at 
three  levels,  yet  the  estimated  increase  of  ore 
is  only  26,595  tons,  that  is,   174,824  minus 
148,229,  and  this  includes   15,000  tons  only 
'  probable.'     The  additional  tonnage  increases 


412 


THE    MINING    MAGAZINE 


the  supposed  profit  by  ;^28,540.  Making  the 
necessary  corrections,  this  addition  to  the 
profit  available,  most  of  it  only  '  probable,' 
is  about  ;^20,000.  Apparently  therefore  the 
ground  to  the  east  of  the  older  workings,  that 
is,  those  existing  on  June  1,  is  decidedly  poor. 
In  any  event  the  manner  of  giving  informa- 
tion is  most  unsatisfactory  and  does  no  credit 
to  those  responsible  for  the  prospectus.  For 
the  excessive  capitalization  we  do  not  blame 
the  engineers,  who  probably  were  not  con- 
sulted in  the  matter.  Nor  do  we  criticize  them 
for  allowing  operating  profits  to  be  passed  as 
the  ultimate  return  of  money  to  shareholders  ; 
for  that  we  blame  an  existing  system  of  loose 
terminology,  fatal  to  technical  accuracy  or 
careful  business.  It  remains  to  summarize 
the  evidence  in  this  case  by  saying  that  the 
Eileen  Alannah  is  not  an  investment  nor  a 
speculation  ;  at  ^460,000  it  is  a  reckless 
gamble  with  big  odds  on  the  dealer. 


East  Rand  Proprietary. 

The  report  of  the  commission  of  inquiry 
was  published  on  November  18  and  at  once 
made  it  clear  that  our  anticipations  were  cor- 
rect. The  analysis  of  the  position  as  stated 
in  the  October  issue  of  this  magazine  has  been 
amply  confirmed.  We  then  summarized  our 
views  by  saying  that  "  up  to  date  the  capacity 
of  the  mines,  mills,  and  the  management,  of 
the  East  Rand  Proprietary  has  been  over- 
estimated by  about  25  per  cent."  An  ambi- 
tious programme  broke  down ;  to  avoid  con- 
fession of  failure  the  returns  were  falsified ; 
and  a  pitiful  series  of  '  irregularities  '  was  com- 
mitted in  order  to  postpone  the  inevitable  ex- 
posure. The  tale  of  a  loss  of  gold  in  the  cya- 
nide plant  proves  to  have  been  merely  the 
attempt  to  drag  a  herring  across  the  trail  of 
gross  mismanagement.  On  November  24  the 
two  directors  representing  the  Central  Mining 
group  resigned,  and  on  November  28  the  rest 
of  the  board  announced  their  intention  of  offer- 
ing their  resignations  at  a  general  meeting  of 


the  shareholders  called  for  February  28,  on 
which  date  a  full  account  will  be  rendered. 
In  the  meantime  the  urgent  need  for  a  stronger 
man  at  the  head  of  the  technical  department 
has  been  met  by  the  appointment  of  Mr.  H. 
Ross  Skinner,  formerly  manager  and  now  con- 
sulting engineer  to  the  Durban  Roodepoort 
mine.  This  does  not  belong  to  one  of  the  big 
groups,  Mr.  Skinner  representing  the  Donald 
Currie  interest,  if  anyone  in  particular.  As  a 
matter  of  fact  he  is  as  nearly  an  independent 
practitioner  as  can  be  found  on  the  Rand,  and 
will  be  remembered  as  the  representative  of 
the  Chamber  of  Mines  who  went  to  China  to 
investigate  coolie  labour  before  its  importation 
into  the  Transvaal.  It  will  be  fortunate  if  the 
administration  of  the  East  Rand  Proprietary 
can  be  rendered  quite  independent  of  market 
influences,  which,  after  all,  are,  not  unreason- 
ably, supposed  to  be  at  the  bottom  of  most  of 
the  vernukerij  that  has  undermined  public 
confidence  in  the  mining  companies  of  the 
Rand.  The  fiasco  has  opened  the  eyes  of 
shareholders  generally  to  the  possible  dangers 
incidental  to  group  control  and  the  extraor- 
dinary irresponsibility  that  may  be  exhibited 
by  men  holding  positions  of  great  trust.  From 
a  technical  point  of  view  some  of  the  blunders 
made  at  the  East  Rand  are  obviously  of  an 
elementary  character.  Any  superintendent  in 
charge  of  a  prospect-hole  and  a  10-stamp  mill 
might  be  ashamed  of  committing  the  errors 
that  have  brought  disgrace  upon  a  vast  min- 
ing enterprise,  owning  a  whole  group  of  mines 
and  mills,  all  operated  on  an  enormous  scale. 
The  estimation  of  tonnage  by  rough  calcula- 
tions based  on  measurement  of  the  mill-resi- 
due is  out  of  date.  As  if  automatic  weigh- 
bridges were  unknown.  The  trucks  from  the 
mine,  on  entering  the  mill,  should  pass  con- 
tinuously over  the  platform  of  a  weighing 
machine,  which  records  the  weight  of  the  ore 
without  interrupting  its  passage  to  the  bins. 
The  increase  of  tonnage  by  adding  waste, 
euphemistically  termed  "ore  below  the  pay- 


DECEMBER,    1911 


413 


limit,"  exhibits  one  of  the  last  attempts,  it 
may  be  hoped,  to  make  a  record  for  low  cost 
by  milling  material  that  ought  to  remain  in 
the  crust  of  the  earth.  The  impoverishment 
of  the  amalgamating  plates  that  ensued  is 
again  a  result  that  was  inevitable,  for  even  the 
veriest  tyro  in  stamp-milling  knows  that  the 
amalgam  on  the  plates  is  robbed  by  passing 
the  pulp  of  barren  rock  over  them.  Apart 
from  these  elementary  blunders  the  deliberate 
falsification  of  statements  as  to  tonnage,  yield, 
and  cost,  the  withholding  of  information  from 
some  of  the  directors,  and  a  final  explanation 
involving  further  useless  prevarication,  all  in- 
dicate a  complete  break-down  of  management. 
What  was  needed  was  a  strong  man  able  to 
refuse  participation  in  all  this  futile  juggling 
with  facts.  It  is  true  Mr.  James  Morris  re- 
signed from  the  dual  management  when  he 
realized  that  afifairs  were  drifting  to  disaster, 
but  as  he  both  remained  silent  and  failed  to 
influence  the  policy  of  the  local  directors,  we 
cannot  absolve  him  from  sharing  some  of  the 
blame  that  is  placed  on  Mr.  Sydney  Penlerick. 
Every  mining  company  is  the  better  for  having 
on  its  staff  at  least  one  man  strong  enough  to 
give  vigorous  opposition  to  wrong-doing.  The 
engineer  unafraid  is  not  necessarily  a  fussy  in- 
dividual prone  to  make  unnecessary  trouble. 
He  is  simply  a  man  of  unswerving  character. 
Lacking  him  the  big  consolidations  are  dan- 
gerous in  the  extreme.  That  is  one  of  the 
morals  of  the  East  Rand  fiasco.  Undoubtedly 
economy  is  gained  by  operating  in  large  units, 
but  the  largest  unit  is  not  necessarily  an  eco- 
nomic unit.  After  a  certain  point  mere  size 
entails  lack  of  control.  The  individual  mines 
of  the  Rand  are  now,  for  the  most  part,  large 
properties  and  big  enterprises.  They  afford 
ample  scope  for  the  ability  of  any  manager. 
It  is  imagined  that  by  consolidating  four  or  five 
big  mines  it  is  easy  to  reduce  the  cost  of  opera- 
tion per  ton  of  ore,  but  that  is  not  so  certain 
as  it  appears,  if  the  individual  mines  have  been 
conducted  properly  and  if  each  represents  an 


economic  unit.  What  is  certain  is  that  the 
placing  of  four  or  five  mines,  with  four  or  five 
managers  of  average  ability,  under  the  control 
of  one  man,  also  of  average  ability,  does  not 
tend  to  greater  efficiency.  If  you  make  a 
super-mining  enterprise  you  must  find  a  super- 
man to  manage  it.  The  true  captain  of  industry 
is  rare.  At  the  East  Rand  he  was  conspicu- 
ously absent. 


Basic  Lining  for  Converters. 

In  the  course  of  his  lecture  on  the  Copper 
Queen  mine,  Mr.  James  Douglas  stated  that 
basic  lining  had  been  proved  superior  to  acid 
lining  for  copper  converters  and  that  the  new 
smelter  at  Douglas  in  Arizona  would  adopt 
the  use  of  this  material.  We  understand  also 
that  Mr.  E.  P.  Mathewson  has  recently  made 
satisfactory  trials  at  Anaconda.  It  appears 
likely  that  this  kind  of  lining  will  be  generally 
adopted,  although  it  is  only  five  years  since 
the  first  successful  use  of  basic  lining  was 
made  at  the  smelter  of  the  Pittsburg  &  Mon- 
tana Co.  at  Butte  by  Mr.  W.  A.  Heywood. 
It  will  be  recalled  that  shortly  after  the 
Manhes  process  of  bessemerizing  copper  was 
introduced,  in  1884,  it  became  evident  that 
the  silicious  lining  of  the  shells  was  a  large 
item  of  expense  and  that  it  would  be  a  great 
improvement  if  a  basic  or  refractory  lining 
could  be  used,  accompanied  by  the  introduc- 
tion of  silica,  either  at  the  top  or  through  the 
tuyeres,  so  as  to  provide  material  for  a  slag. 
Experiments  were  made  at  the  two  American 
smelters  that  were  the  first  to  adopt  convert- 
ing :  the  Parrot  and  the  Anaconda  works,  both 
in  Montana.  Other  instructive  trials  were 
made  by  Mr.  August  Raht  at  Pueblo,  Color- 
ado. But  all  of  these  proved  failures.  As 
the  materials  used  in  the  first  attempt  are  the 
same  as  those  now  employed  successfully,  it 
may  be  asked  why  it  is  now  easy  to  do  what 
was  formerly  impracticable  ?  The  answer  is 
that  the  converter  of  today  is  much  larger,  so 
that  the  proportion  of  heat  lost  by  radiation  is 


414 


THE    MINING    MAGAZINE 


less,  and  the  grade  of  the  matte  converted  is 
lower,  hence  more  heat-units  are  generated. 
Incidentally  we  may  say  that  while  the  in- 
creased dimensions  of  the  converter  have  been 
the  controlling  factor  in  this  development,  it 
is  probable  that  in  the  latest  designs  the  size 
has  been  allowed  to  exceed  the  economic  limit. 
After  the  first  efforts  no  progress  was  made 
until,  as  stated,  in  1906  at  the  Pittsburg  & 
Montana  works,  near  Butte,  a  trial  was  made, 
with  magnesite  brick,  by  Mr.  Ralph  Baggaley. 
Small  water- jacketed  converters  had  been  tried 
in  vain,  whereupon  a  large  converter  was  con- 
structed and  proved  entirely  successful.  The 
metallurgist  was  Mr,  W.  A.  Heywood,  who 
published  an  account  of  his  operations  in  the 
Mining  &  Scientific  Press  of  April  28,  1906. 
In  the  meantime  the  only  gain  by  the  new 
method  was  in  the  labour  incidental  to  making 
a  lining  for  the  converter,  although  experi- 
ments in  the  Washoe  smelter,  at  Anaconda, 
showed  that  the  life  of  the  acid  lining  was 
prolonged  when  a  large  quantity  of  silicious 
ore  was  added  to  the  charge  in  the  converter 
before  blowing.  Technical  descriptions  of  the 
experiments  made  by  Messrs.  W.  H.  Peirce 
and  E.  A.  C.  Smith  at  the  Baltimore  and  Perth 
Amboy  smelters,  together  with  details  of  the 
converter  designed  by  them,  appeared  in  1910 
in  the  Engineering  &  Mining  Journal. 
Since  then  the  process  has  been  adopted  in 
several  smelting  establishments.  For  copper 
ores  containing  silver  the  use  of  the  converter 
is  not  well  adapted,  unless  modern  methods  for 
the  recovery  of  dust  and  fume  are  employed. 
As  soon  as  the  white-metal  stage  is  reached, 
that  is,  the  point  at  which  the  molten  copper 
sulphide  is  formed,  the  loss  of  silver  in  es- 
caping gas  is  great.  Losses  of  silver  in  the 
converter  discharge  are  rarely  less  than  20% 
and  of  copper  never  less  than  5%,  and  the  sub- 
sequent recovery  of  the  fume,  whether  in 
chambers  or  bags,  is  not  so  perfect  as  to  war- 
rant the  risk.  Speaking  generally,  the  basic- 
lined  converter  is  especially  applicable  to  a 


low-grade  matte  made  from  a  silicious  ore  in 
the  blast-furnace.  Any  silicious  material  can 
be  used  as  flux  in  the  basic  -  lined  vessel, 
whereas  the  range  of  ores  suited  to  the  acid 
lining  is  small.  Mr,  Douglas's  frank  state- 
ment marks  an  epoch  in  copper  smelting,  and 
will,  we  trust,  elicit  fresh  testimony  in  regard 
to  the  use  of  basic  lining  in  other  parts  of  the 
world. 


Loose  Reporting. 

Some  of  our  readers  may  occasionally  feel 
restive  at  criticisms  offered  by  us  on  care- 
less terminology  and  they  may  be  tempted 
to  blame  us  for  placing  undue  emphasis  on 
non-essentials.  We  are  not  without  prac- 
tical experience  in  these  matters  and  we 
do  not  lay  stress  upon  them  without  good 
reason.  Mining  is  based  on  scientific  prin- 
ciples ;  the  principles  become  demoralized 
by  the  use  of  loose  terminology.  Wrong 
ideas  and  incorrect  inferences  inevitably  re- 
sult from  the  slipshod  phraseology  employ- 
ed by  the  careless  practitioner.  We  can 
give  an  example  that  has  just  been  brought 
to  our  attention.  In  the  first  annual  report  of 
the  Frontenac  Consolidated  Mines,  an  English 
company  operating  in  Colorado,  it  is  stated 
by  Mr.  Henry  P.  Lowe,  the  managing  direc- 
tor, that  assured  profits  can  be  won  by  en- 
largement of  the  mill,  based  on  successful  ex- 
periments recently  made.  To  that  end  an 
issue  of  ^22,000  in  debenture  bonds  is  to  be 
placed  on  the  market,  the  shareholders  having 
the  first  opportunity  to  subscribe.  This  is 
done  on  the  basis  of  Mr.  Lowe's  report,  which 
is  couched  in  vague  phraseology,  backed  by 
evidence  of  an  inadequate  character.  For 
the  purpose  of  this  criticism  it  suffices  to  refer 
to  the  statement  that  affords  the  motive  for 
the  new  issue  of  capital.  It  is  asserted  that 
the  further  development  of  the  mine  would 
result  as  follows  : 

6000  tons  milled    at  $8'35  per  ton  $50,100  per  month 

Cost  of  production  at  $2'83     .,     ,,    Sl6,980    ., 

Proceeds $33,120  per  month 


DECEMBER,    1911 


415 


"  Added  to  this  sum  of  $33,120"00  per  month 
profit  would  be  the  monthly  shipments  of 
smelting  ores,  and  a  charge  of  45  cents  per 
ton  for  smelter  freight  and  charges  will  fall 
to  be  deducted,  together  with  a  small  charge 
for  amortization  of  capital  in  respect  of  de- 
velopment." No  statement  having  any  pre- 
tence to  accuracy  could  be  more  misleading. 
Note  should  be  taken  of  the  unnecessary  de- 
cimal and  its  following  ciphers,  suggesting  an 
absolute  figure  not  to  be  burdened  by  a  frac- 
tion ;  also  of  the  delicate  detail  in  regard  to 
amortization  of  capital  expended  in  develop- 
ment, as  if  this  small  item  were  of  any  im- 
portance in  face  of  the  probability  of  large 
errors  in  the  preceding  estimates.  For  these 
are  woefully  erroneous.  Knowing  this  par- 
ticular mining  district  we  hesitate  to  accept 
$2*83  as  the  total  cost  of  production,  and  that 
hesitation  is  not  removed  by  reading  the  item- 
ized data  given  in  the  context.  This  how- 
ever is  relatively  unimportant.  We  come  to 
the  ore  that  is  to  yield  $8'35  per  ton.  Else- 
where in  the  report  it  is  stated  that  $8"35  is 
the  average  value  of  the  crude  ore  as  received 
at  the  mill.  Hence  if  that  ore  yields  $8*35 
per  ton  the  extraction  is  at  the  rate  of  100%. 
Having  regard  to  the  fact  that  the  process  is 
stamp-milling  and  concentration,  it  is  unlikely 
that  the  extraction  is  over  85%.  But  even 
this  is  largely  in  the  form  of  a  concentrate, 
which  is  sent  to  the  smelter,  from  which  a  re- 
turn of  not  more  than  95%  is  likely  ;  thus  an 
optimistic  estimate  would  give  95%  of  85%,  or 
80*75%,  as  the  probable  extraction.  Deduct- 
ing the  estimated  cost  of  production  from  the 
assay-value  of  the  ore  to  be  treated,  the  en- 
gineer gets  $33,120  as  the  fictitious  '  proceeds.' 
But  the  error  does  not  end  here  ;  by  a  mere 
flourish  of  the  pen  he  turns  proceeds  '  into 
profits  '  in  the  very  next  line  of  the  report. 
Thus  by  the  careless  use  of  '  average  value  ' 
and  of  '  proceeds '  he  reaches  a  visionary 
'profit'  of  $33,120*00— note  the*00.  Of  course 
such  fundamental  blunders  vitiate  the  entire 


report,  with  its  estimate  of  ore  blocked  out, 
its  milling  test,  and  its  forecasts. 

While  commenting  on  this  case  we  may 
direct  attention  to  a  radically  unwise  proce- 
dure adopted  by  some  mining  companies, 
namely,  allowing  the  direction  of  the  mine  to 
remain  in  the  hands  of  a  manager  identified 
with  the  vendors.  It  is  bad  business.  Any 
British  company  about  to  acquire  a  mine 
should  act  on  the  advice  of  an  engineer  re- 
tained in  their  interest,  as  was,  we  believe, 
done  in  the  case  of  the  Frontenac,  but  this 
precaution  should  be  followed  by  placing  the 
mine  in  charge  of  their  own  engineer,  not  a 
nominee  of  the  vendors.  The  Frontenac  di- 
rectors apparently  are  not  advised  by  a  con- 
sulting engineer  of  their  own  appointment, 
but  are  acting  on  the  advice  of  a  local  prac- 
titioner whose  interest  may  not  be  parallel 
with  their  own.  The  procedure  is  fair  neither 
to  Mr.  Lowe  nor  to  the  English  directors. 
In  mining  as  in  other  affairs  it  is  well  to  re- 
member the  old  Roman  maxim  :  Caveat  emp- 
tor. He  who  does  not  is  disregarding  an 
elementary  rule  of  sound  business. 


The  Copper  Queen. 

Thelecture  delivered  by  Mr.  James  Douglas, 
LL.D.,  McGill  University,  on  November  Z'i, 
on  the  mining  and  metallurgical  developments 
based  upon  the  exploitation  of  the  Copper  Queen 
mine,  was  a  notable  event  in  the  history  of  our 
Institution.  Themineandthespeakerare  both 
known  as  illustrations  of  the  most  dignified 
aspects  of  mining  adventure,  giving  the  word 
its  old  and  romantic  meeting.  None  of  the 
fulsome  panegyrics  of  the  vote  of  thanks  were 
required  to  indicate  how  much  the  audience 
appreciated  the  magnitude  of  an  accomplish- 
ment that  made  the  Copper  Queen  one  of  the 
great  mines  of  the  world.  Quorum  magna 
pars  fuit,  but  Mr.  Douglas  is  the  last  man  in 
the  world  to  accept,  with  any  sort  of  pleasure, 
the  credit  for  the  whole  performance,  which  he 
shared  with  Lewis  Williams,  L.  D,  Ricketts, 


416 


THE    MINING    MAGAZINE 


John  Langton,  and  George  B.  Lee.  It  is 
rarely  indeed  that  the  story  of  a  mine  is 
told  in  so  informing  a  manner,  and  we  feel 
sure  that  it  must  have  been  worth  many  or- 
dinary lectures  to  the  students  who  sat  on  the 
back  benches.  If  some  of  them  murmured 
"  There's  the  Yankee  for  you  "  to  the  speaker's 
outspoken  comment  on  British  unprogressive- 
ness,  as  regards  the  scrapping  of  obsolete 
plant,  it  was  because  they  failed  for  a  moment 
to  appreciate  the  essential  modesty  of  a  great 
man,  whose  criticisms  were  offered  more  in 
sorrow  than  in  conceit  of  his  success.  It  is 
safe  to  say  that  while  we  as  Britishers  do  not 
take  kindly  to  the  bumptious  assumption  of 
technical  superiority  expressed  sometimes  by 
our  younger  American  friends,  we  accept  as  a 
compliment  the  advice  tendered  by  a  Scottish 
Canadian  veteran,  whose  right  to  do  so  is 
writ  large  on  his  own  record. 

The  Copper  Queen  mine,  at  Bisbee,  Arizona, 
was  based  on  a  discovery  made  in  1878.  The 
presence  of  a  big  orebody  was  indicated  by 
a  prominent  outcrop  in  a  ridge  of  limestone. 
The  orebody  first  discovered  came  to  a  sud- 
den end,  but  a  stringer  or  leader  in  the  lime- 
stone was  followed  to  another  large  mass  of 
ore,  and  this  led  to  a  series  of  orebodies  dis- 
tributed within  a  thickness  of  400  feet  of  Up- 
per Carboniferous  limestone.  Apparently  the 
copper  ore  was  derived  by  concentration  from 
the  degradation  of  pre-existing  larger  deposits 
of  slightly  cupriferous  iron  pyrite,  leaving 
masses  of  rich  ore  covered  by  the  ferruginous 
clay  resulting  from  the  decomposition  of  the 
pyritic  limestone.  The  continuity  of  the  ore- 
channel  was  not  appreciated  ;  hence  the  ro- 
mantic story  of  the  Irish  Mag  and  its  progeny 
the  Calumet  &  Arizona  and  Superior  &  Pitts- 
burg enterprises.  As  might  be  supposed,  this 
type  of  ore  deposit,  consisting  of  chambers  in 
limestone  connected  by  ore-bearing  fractures, 
afforded  a  grand  opportunity  for  the  mis- 
chievous mining  regulation  called  the  Law  of 
the  Apex.      Fortunately  Mr.  Douglas  and  his 


associates  were  as  wise  as  they  were  ener- 
getic, and  foresaw  the  possibility  of  intermin- 
able litigation.    Therefore  at  successive  stages 
in  the  history  of  the  Copper  Queen  Consoli- 
dated  they    entered  into    friendly    compacts 
with  their  neighbours,  whereby  extra-lateral 
rights  were  mutually  abrogated.     This  is  an 
important  part  of  the  story.     For  the  rest,  we 
were  impressed  by  the  emphasis  laid  by  the 
speaker  on  the  fact  that  he  and  his  fellow- 
operators  repeatedly  assumed  big  risks  in  the 
spending  of  money  in  large-scale  prospecting, 
in  the  purchase  of  adjoining  territory,  and  in 
the  scrapping  of  machinery  that  became  obso- 
lete as  the  undertaking  progressed.     This  was 
pre-eminently  a  feature  of  the  smelting  plant. 
Beginning  with  a  36-inch  water-jacketed  blast- 
furnace, the  metallurgical  operations  grew  un- 
til for  one  year,  at  least,  the  output  of  copper 
was  the  largest  of  any  single  mine  in  America. 
Successive  enlargements  of  the  plant  resulted 
in  a  smelter 'at  Bisbee  that  cost  $1,500,000, 
but  when  economic  conditions  necessitated  a 
new  plant,  built  at   Douglas,  there   was  no 
hesitation  in  scrapping  the  old  one,  so  that, 
as  Mr.  Douglas  said,  an  asset  that  appeared 
on  the  books  at  between  one  and  two  million 
dollars  became  worth  between  one  and  two 
cents.      No    feature    of  American   industrial 
progress  is  more  marked  than  the  willingness 
to  discard  obsolete  plant  in  favour  of  modern 
equipment,  when  it  can  be  seen  that  the  sav- 
ing will   amortize   the  capital   invested.     As 
the  lecture  will  shortly  appear  in  print,  we 
forbear  to  quote  further  details.     We  note, 
however,  the  decision  to  replace  the  acid  lin- 
ing of  converters  by  basic  lining,  in  accord, 
we  presume,  with  recent  experience  at  Ana- 
conda and  Garfield.     The  presence  of  water 
(up  to  0"33%)  in  copper  ingots  due  to  absorp- 
tion during  cooling  was  a  remarkable  bit  of 
information.     Another  was  the  loss  of  copper 
in  dust  and  the  ascertainment  of  the  fact  that 
3  feet  per  second  is  the  maximum  velocity  of 
movement  consistent  with  effective  dust-col- 


DECEMBER,    1911 


417 


lection.  The  use  of  oil,  first  from  Kansas 
and  now  from  California,  was  mentioned  as 
conducing  to  economy  and  efficiency  in  fur- 
nace operation,  but  the  speaker  expressed 
keen  regret  that  a  natural  product  containing 
so  many  valuable  ingredients  should  be 
squandered,  seeing  that  it  was  a  resource 
destined  to  be  exhausted.  As  an  illustration 
of  the  development  of  industry,  nothing 
could  have  been  more  effective  than  the 
lantern-slides  exhibiting  the  growth  of  the 
system  of  transport  essential  to  the  mine,  from 
the  18-mule  teams  of  the  early  days  to  the 
railway  train  of  50  cars  each  carrying  50  tons 
of  ore  from  the  mine  at  Bisbee  to  the  smelter 
at  Douglas.  Finally  the  statistics  told  an 
eloquent  story,  showing  a  total  output  of 
880,000,000  pounds  or  400,000  tons  of  metallic 
copper,  yielding  $35,000,000  or  ;^7,000,000 
in  dividends.  The  story  of  the  Copper  Queen 
constitutes  one  of  the  most  notable  chapters 
in  the  history  of  mining,  and  exhibits  a  com- 
bination of  pluck,  energy,  and  wisdom  rarely 
conjoined  in  any  mining  enterprise. 


The  Finance  of  a  Mine. 

In  this  issue  we  close  the  series  of  articles 
contributed  by  Mr.  M.  H.  Burnham  on  the 
principles  underlying  the  finance  of  mining 
enterprises.  These  articles  have,  we  believe, 
presented  an  important  subject  in  an  original 
manner  ;  they  have  been  well  worthy  of  care- 
ful reading  ;  and  they  have  developed  several 
new  points  in  the  economics  of  mining.  It  is 
likely  that  the  mathematical  form  given  to 
some  of  the  author's  ratiocinations  has  intimi- 
dated all  but  serious  students,  and  we  fear 
that  the  use  of  formulas  may  have  led  some 
of  the  less  sophisticated  to  infer  that  mining 
valuation  is  a  precise  science.  However,  that 
is  no  fault  of  the  author,  for  it  is  obvious  that 
logical  ideas  can  be  expressed  in  the  terms  of 
mathematics  and  are  clarified  thereby.  Mr. 
Burnham  has  undoubtedly  helped  to  crystal- 
lize several  excellent  but  vague  notions  in- 


volved in  current  practice,  and  he  might  per- 
haps have  made  his  treatment  of  them  more 
effective  if  he  had  not  adopted  so  severe  an 
attitude  toward  other  members  of  the  profes- 
sion, while  basing  too  much  of  his  argument 
on  one  case,  that  of  the  Santa  Gertrudis,  in 
which  personal  prejudice  was  unavoidably  in- 
volved. However,  the  recognition  of  these 
two  defects  in  Mr.  Burnham's  treatment  of 
his  subject  is  not  inconsistent  with  our  appre- 
ciation of  the  value  of  the  articles  we  have 
published.  He  has  made  good  several  points 
of  paramount  importance,  not  the  least  of 
which  is  the  necessity  for  an  intelligent  re- 
cognition and  understanding,  by  engineers,  of 
the  economics  of  mining  finance.  Our  con- 
viction that  aloofness  from  actual  participa- 
tion in  promotion  is  best  both  for  the  indi- 
vidual and  the  profession  does  not  entail  ac- 
quiescence in  ignorance  of  the  elementary  prin- 
ciples of  finance  ;  on  the  contrary,  it  is  plain 
that  an  engineer  who  reports  on  a  mine  should 
understand  the  purpose  to  which  his  report 
will  be  put,  and  thereby  give  advice  that  may 
be  not  merely  academic  but  applicable  to  busi- 
ness. The  drift  of  events  is  all  against  the 
sort  of  detachment  that  caused  engineers  at 
one  time  to  write  ornate  descriptions  of  ore 
deposits  on  the  supposition  that  such  docu- 
ments could  be  of  any  practical  utility  to  a 
client  anxious  to  make  money  by  exploiting 
those  ore  deposits.  Engineers  nowadays  are 
asked  to  advise  in  negotiations  ;  they  are  ex- 
pected to  correlate  facts  with  finance  ;  they 
may  serve  as  directors,  and  thus  assume  the 
duties  of  a  trustee.  In  other  words,  mining  is 
not  a  scientific  pursuit  but  a  business  based 
on  facts  as  ascertained  by  scientific  methods. 
The  next  point  scored  by  Mr.  Burnham  is 
the  '  risk-rate,'  the  recognition  of  the  principle 
that  the  investor  should  expect  not  only  a  bank- 
rate  of  interest  but  as  much  more  as  will  cover 
the  inherent  risk  of  the  enterprise.  Thus  for 
example,  the  Goldfield  Consolidated,  a  mine 
in  Nevada  that  is  the   most  productive  in  the 


418 


THE    MINING    MAGAZINE 


world  at  the  present  moment,  has  a  reserve  of 
ore  so  small  compared  to  its  annual  produc- 
tion that  to  an  investor  it  assures  the  return 
of  only  a  small  part  of  the  capital  represented 
by  the  market  valuation  ;  hence  a  Consol  rate 
of  3%  would  be  ridiculous  ;  to  cover  the  essen- 
tial risk  a  return  of  at  least  35%  is  required, 
or  a  risk-rate  of  32%  above  Consols,  that  is, 
if  the  mine  be  valued  on  the  basis  of  a  three 
years  purchase.  On  the  other  hand,  the  best 
of  the  Rand  consolidations,  despite  the  East 
Rand  Proprietary  fiasco,  have  a  life  and  a  rate 
of  production  justifying  a  much  lower  estimate 
of  risk,  thus  warranting  a  return  of,  say,  5% 
above  the  Consol  rate.  Of  course,  experi- 
enced engineers  have  always  had  this  idea  at 
the  back  of  their  heads,  but  Mr.  Burnham  has 
brought  it  to  the  front.  It  is,  for  instance,  an 
advance  upon  the  advice,  excellent  as  it  was, 
of  Mr.  J.  H.  Curie,  who  generalized  broadly 
in  a  demand  that  a  gold  mine,  with  ore  in  the 
bottom,  should  have  60%  of  its  price  assured 
and  be  able  to  pay  10/^  on  the  capital.  That 
is  a  test  inadequate  to  cover  the  wide  diver- 
sity of  risk  inherent  in  precious  metal  mming. 
Mr.  Burnham's  is  much  better. 

Another  feature  of  this  series  of  articles  has 
been  the  effort  to  establish  a  unit  for  measur- 
ing the  probability  of  persistence  of  the  ore- 
body,  or  '  shoot-extension.'  This  unit  is  called 
the  '  shoot-foot,'  meaning  the  amount  of  money 
to  be  won  per  foot  in  depth.  While  this  unit 
may  not  be  generally  accepted,  it  is  obvious 
that  Mr.  Burnham's  analysis  of  the  conditions 
determining  the  ascertainment  of  this  factor 
is  most  helpful.  It  tends  to  develop  the  men- 
tal concept  on  which  estimates  of  this  kind  are 
based.  Like  Mr.  H.  F.  Marriott's  '  square 
fathom,'  the  particular  unit  selected  is  not  im- 
portant, but  the  underlying  principle  is  vital. 
This  applies  also  to  Mr.  Burnham's  discussion 
of  deferred  dividends.  It  may  not  be  possible 
to  adopt  any  cut  and  dried  programme,  nor  to 
carry  out  a  prescribed  formula,  but  most  as- 
suredly it  is  important  that  in  these  matters 


we  should  be  guided  by  scientific  principles. 
Such  are  those  submitted  by  Mr.  Burnham. 
We  commend  them  to  the  earnest  study  of 
the  profession.  In  order  to  bring  the  various 
aspects  of  the  problem  before  our  readers,  we 
have  asked  other  engineers  to  discuss  them 
in  the  magazine.  W^e  shall  shortly  publish 
several  contributions  on  the  subject. 


Seasonal  Variations. 

Those  who  are  cognizant  of  the  varying 
conditions  affecting  the  economy   of  mining 
operations  are  aware  that  winter  and  summer, 
drought  and  monsoon,  rain  and  snow,  variously 
aid  or  hinder  a  mine  manager  to  an  extent 
measurable  in  dollars  and  cents,  or  shillings 
and  pence,  per  ton  of  ore.     The  migration  of 
Kaffirs  is  a  cause  of  annual  perturbation  to 
mine  operators  on  the  Rand,  the  inevitable 
nature  of  which  is  obscured  by  needless  de- 
pression when  the  native  goes  to  his  kraal  to 
sow  his  mealie,  as  it  is  by  the  equally  unin- 
telligible elation  of  bull  speculators  when  that 
useful  duty  has  been  performed  and  the  Kaffir 
leaves  his  many  wives  for  another  campaign 
at  the  mines.     When  the  Alaska-Treadwell 
closes  its  100-stamp  mill  on   Douglas  island 
at  the  approach  of  winter  because  its  water- 
power  is  congealed  by  frost,  necessitating  the 
operation  of  only  a  part  of  its  milling  plant 
by  the  use  of  steam,  there  is  a  decrease  of 
output    that  intimidates  the   speculator  who 
has  been  a  shareholder  for  a  few  months  only. 
We  note  that  this  recurrent  decrease  of  pro- 
duction is  to  be  obviated  by  the  installation 
of  a  hydro-electric  plant,  but  the  illustration 
will   serve,   even   if  it  be  retrospective.     In 
Colorado  the  shipment  of  concentrate  from 
a    mill    near   the    'timber    line'    may    be   in- 
terrupted  by    the  winter    snows.      In    other 
regions  —  such  as   Michigan  —  transport    by 
water  in  summer  may  be  followed  in  winter 
either  by  overland   freighting  or  by  a   total 
stoppage  of  outgoing  mineral  production.     In 
the  Malay  States  the  monsoon  may  interrupt 


DECEMBER,    1911 


419 


the  winning  of  tin  by  flooding  the  super- 
ficial workings  of  alluvial  mines.  These  and 
similar  recurrent  vicissitudes  affect  the  pro- 
ductivity of  enterprises  repeatedly  and  regu- 
larly, so  that  any  well  informed  speculator 
may  derive  benefit  from  them,  and  any  com- 
fortable investor  becoming  aware  of  them  may 
save  himself  unnecessary  anxiety. 


Secretaries. 

In  our  last  issue  we  had  so  much  to  say 
regarding  the  Camp  Bird  that  we  refrained 
from  making  any  reference  to  a  pleasant  in- 
cident that  marked  the  recent  annual  meeting. 
We  refer  to  the  cordial  acknowledgment  by 
the  chairman,  Mr.  Arthur  M.  Grenfell,  of  a 
sense  of  obligation  to  the  secretary  of  the 
company,  Mr.  A.  A.  Kelsey,  for  his  efficient 
services.  The  acknowledgment  does  credit 
to  both.  Unfortunately  such  public  recogni- 
tion of  the  good  work  done  by  a  faithful  and 
intelligent  secretary  is  not  as  frequent  as  it 
should  be.  Assuredly  a  just  reason  for  recog- 
nition exists  often.  Those  who  take  even  a 
detached  view  of  company  organization  in 
London  are  aware  how  much  depends  upon 
the  secretary.  Occasionally  he  is  a  mere 
clerk,  of  minor  intelligence  and  able  to  claim 
nothing  better  than  a  bowing  acquaintance 
with  practical  mining.  Often,  however,  he 
is  a  tactful  personage,  possessed  of  a  wider 
experience  of  mining  than  any  director  on  his 
board,  and  keenly  alive  to  the  salient  factors 
determining  the  success  of  the  administration. 
We  know  secretaries  who  have  been  mine 
managers,  but  exercise  a  diplomatic  reserve 
in  exhibiting  a  first-hand  knowledge  of  essen- 
tial principles.  They  conduct  a  sort  of  kin- 
dergarten correspondence  school  for  ignorant 
but  insistent  shareholders.  They  receive  re- 
presentatives of  the  Press  with  courtesy,  and 
dismiss  them  with  alacrity  ;  in  short,  they  are 
pivots  around  which  a  vast  amount  of  com- 
plicated business  turns  with  a  smoothness  and 
despatch  that  almost  obscures  the  essential 
6—3 


usefulness  of  their  daily  work.  Shareholders 
who  read  the  lucid  review  of  a  year's  opera- 
tions as  read  by  an  impressive  chairman  do 
not  know  that  an  humble  secretary  has  care- 
fully prepared  the  speech.  All  goes  well  if 
the  chairman  sticks  to  the  text ;  but  occasion- 
ally he  breaks  from  the  leash  and  makes  rash 
statements,  which  the  poor  secretary  has  to 
reconcile  with  brutal  facts  by  means  of  a  cir- 
cular or  on  the  occasion  of  the  next  speech, 
by  which  time  the  chairman's  stray  remarks 
have  come  home  to  roost,  and  that  rare  bird, 
a  well  informed  shareholder,  has  arisen  in  the 
body  of  the  hall  to  put  a  question  that  cannot 
be  evaded.  Secretaries  must  be  born  humor- 
ists, or  they  would  die  of  chagrin.  But,  like 
diplomats,  they  know  how  to  keep  the  joke  to 
themselves.  It  is  the  secretary  who  takes 
himself  too  seriously  that  gets  into  trouble. 
Not  for  him  to  plume  himself  on  his  know- 
ledge of  mining,  however  deep  ;  not  for  him 
to  show  a  too  intrusive  hand  in  affairs,  how- 
ever necessary  he  may  be.  Particularly  will 
he  avoid  infringing  on  the  duties  of  the  con- 
sulting engineer.  When,  for  instance,  the 
secretary  of  the  Golden  Horse-Shoe  sent  a 
cablegram  lately,  giving  his  opinion  on  sundry 
technical  affairs  at  Kalgoorlie,  he  committed 
an  obvious  indiscretion.  If  the  Golden  Horse- 
Shoe  company  has  a  consulting  engineer,  that 
gentleman  ought  to  have  called  upon  the  sec- 
retary to  mind  his  own  business  and  if  the 
directors  had  any  authority  they  ought  to  stop 
a  procedure  so  entirely  improper.  That  was 
a  capital  blunder  in  company  administration. 
Other  secretaries  know  as  much  about  mining 
as  he  of  the  Golden  Horse-Shoe,  but  they 
know  full  well  that  it  is  not  for  them  to  tres- 
pass into  the  preserves  of  the  consulting  en- 
gineer or  the  mine  manager.  However,  such 
indiscretions  are  rare.  The  one  quoted  serves 
to  emphasize  the  rarity  of  them.  For  it  is 
a  pleasant  fact  that  the  engineer  of  a  com- 
pany is  apt  to  find  in  the  secretary  a  guide, 
philosopher,  and  friend.     To  him  he  can  speak 


420 


THE    MINING    MAGAZINE 


more  frankly  than  to  his  directors,  to  him  he 
can  look  for  support  at  the  board  meeting,  in 
him  he  can  find  an  interpreter  to  the  lay  mind 
of  the  simple  shareholder.  To  secretaries  the 
mining  industry  owes  a  debt  which  it  is  our 
pleasure  to  record  and  to  acknowledge. 


A  Fundamental  Factor. 

Recent  episodes  in  connection  with  impor- 
tant mines  point  to  the  conclusion  that  the 
underground  operations  of  a  mining  company 
may  suffer  by  reason  of  the  disproportionate 
interest  taken  in  metallurgical  methods,  equip- 
ment of  machinery,  the  sampling  and  estima- 
tion of  ore,  the  preparation  of  reports,  and  the 
stimulation  of  the  share  market.  Directors, 
and  the  shareholders  for  whom  they  are  trus- 
tees, are  apt  to  appreciate  a  metallurgical  pro- 
cess the  cost  of  which  can  be  stated  in  shil- 
lings and  the  extraction  in  percentages  ;  they 
can  admire  a  plant  or  machinery  that  runs 
without  a  hitch  and  is  kept  in  beautiful  order  ; 
they  have  a  respect,  amounting  to  awe,  for 
estimates  of  reserves  and  even  for  average 
assays  that  are  stated  in  refinements  stretch- 
ing to  three  decimal  points  ;  they  read  reports 
as  schoolboys  who  peruse  French  novels  that 
they  imperfectly  understand ;  and  they  write 
to  the  financial  papers  to  explain  why  the 
shares  in  which  they  take  peculiar  personal 
interest  are  too  low,  having  regard  to  the  facts 
as  they  comprehend  them.  Of  course,  the 
shareholder  is  still  something  of  a  lamb  and 
he  does  not  yet  get  as  fair  a  run  for  his  money 
as  he  might ;  but  conditions  are  vastly  better 
than  they  used  to  be  twenty  years  ago  and  the 
general  spread  of  knowledge  on  mining  affairs 
has  reached  even  the  hidden  mental  recesses 
of  the  man  in  the  street.  We  congratulate 
him,  but  we  warn  him,  and  particularly  the 
more  enlightened  persons  who  undertake  to 
guide  him,  that  while  the  eyes  of  the  sup- 
posedly sagacious  have  been  fixed  on  plant 
and  machinery,  on  reports  and  quotations,  the 
fundamental  factor  in  mining  is  being  neglec- 


ted, namely,  the  finding  of  ore.  Indeed,  the 
next  stage,  the  economic  breaking  of  ore  and 
the  cheap  removal  of  it  to  surface  is  less  con- 
sidered than  the  treatment  in  the  mill  and  the 
realization  on  the  market.  We  need  to  focus 
our  eyes  so  that  we  can  see  how  things  are 
done  in  the  dark  places  underground,  to  ap- 
preciate the  first  of  the  sequence  of  operations 
contributory  to  the  winning  of  the  metals,  and 
not  to  give  our  attention  only  to  the  perfor- 
mances on  the  sunlit  surface  of  things.  A 
mine  is  made  underground.  There  is  the 
general  manager  and  the  consulting  engineer, 
the  surveyor  and  the  assayer,  the  director  and 
the  secretary  :  but  economic  success  depends 
chiefly  on  a  more  humble  individual,  namely, 
the  foreman,  *  shift-boss,'  or  '  agent.'  And  as 
the  other  gentlemen  select  good  foremen  and 
encourage  them  to  fruitful  purpose,  in  so  far 
they  also  perform  a  useful  function.  As  a 
matter  of  fact,  the  foremen,  who  have  im- 
mediate charge  of  the  miners  and  direct  them 
what  to  do  and  in  which  direction  to  do  it,  are 
not  an  ornate  portion  of  the  staff  and  come  in 
close  contact  only  with  their  next  in  rank,  the 
superintendent.  Obviously  the  selection  of 
the  right  subordinates  is  of  vital  importance 
to  the  life  of  a  mine,  and  the  superintendent 
or  manager  who  knows  how  to  make  such  a 
selection  is  fulfilling  a  large  part  of  his  duty. 
To  do  this  he  must  himself  be  a  good  miner, 
familiar  with  underground  work,  and  not  un- 
willing to  spend  as  much  time  below  the  sur- 
face as  in  his  chair  at  the  office.  Thus  we 
come  to  the  point  on  which  we  desire  to  lay 
emphasis  :  that  in  the  haste  to  improve  the 
other  departments  on  the  upper  floors  of  the 
mining  structure  we  have  tended  to  neglect 
the  essential  importance  of  the  fundamental 
portion — the  ground-floor,  as  it  were,  of  the 
many-storied  edifice  constituting  a  large  min- 
ing enterprise.  We  need  miners  and  metal- 
lurgists, accountants  and  secretaries,  directors 
and  brokers,  but  we  need  first  of  all  the  man 
who  can  find  ore  and  then  extract  it  cheaply. 


b 


SPECIAL    CORRESPONDENCE 

News   from  our  own  Correspondents  at  the  principal  mining  centres 


JOHANNESBURG. 
Mining  and  Politics. — The  great  mining 
district  of  the  Rand  has  within  the  last  week 
been  inspected  by  many  country  members  of 
the  House  of  Assembly.  The  Johannesburg 
Town  Council,  the  Chamber  of  Mines,  and 
the  people  of  Johannesburg  generally,  did  their 
best  to  show  the  legislators  all  there  is  worth 
seeing  in  and  around  Johannesburg.  The  min- 
ing industry  is  regarded  with  suspicion  by 
many  members  of  the  House  of  Assembly. 
The  idea  that  it  is  an  enormous  unscrupu- 
lously managed  business  seems  to  prevail  in 
the  minds  of  many  of  the  present  Government 
party.  The  wonderful  progress  made  within 
the  last  25  years  is  not  fully  realized.  At  the 
present  time  about  24,000  whites  and  200,000 
natives,  earning  altogether  about  /"  12,000,000 
per  annum,  are  employed  on  the  mines  of  the 
Transvaal.  These  mines  at  the  present  time 
are  worked  on  a  sounder  basis  than  ever  be- 
fore, with  the  consequence  that  the  mining 
population  is  becoming  more  settled,  as  time 
goes.  A  mining  life  is  after  all,  even  to  the 
keenest  operator,  not  an  ideal  one,  and  it  is 
noticeable  that  throughout  all  classes  of  the 
community  there  is  a  growing  desire  to  invest 
money  in  land.  The  result  is  that  the  price 
of  good  farming  land  is  rapidly  increasing. 
South  Africa  has  a  great  future  as  an  agri- 
cultural country,  and  in  a  short  time,  with  a 
prosperous  mining  industry,  a  large  area  of 
farms  will  be  held  by  men,  who  have,  while 
employees  at  the  mines,  saved  sufficient  money 
to  enable  them  to  settle  in  the  country.  Mean- 
while, it  is  imperative,  for  the  good  of  South 
Africa,  that  the  mining  industry  should  be 
fostered  by  the  Government,  instead  of  being 
made  the  object  of  attack  on  every  possible 
occasion.  The  following  points  were  impressed 
upon  the  visiting  members  of  the  House  of 
Assembly  by  the  Chamber  of  Mines  : 

(1)  That  this  is  a  factory  turning  out,  on  an 

enormous  scale,  an  average  value  of 
about  27s.  of  gold  per  ton  of  ore. 

(2)  That  a  reduction  of  the  present  working 

cost  will  ensure  the  persistence  of 
the  industry. 

(3)  That  a  prosperous  future  can  be  guar- 

anteed by  a  reduction  of  indirect 
taxation  and  by  an  adequate  supply 
of  efficient  labour  to  the  mines. 


The  Transvaal   Gold   Mining  Estates 

held  its  annual  meeting  recently,  at  which  the 
chairman  was  at  great  pains  to  contradict  ru- 
mours in  circulation  reflecting  unfavourably 
on  the  prospects  of  the  company.  What  the 
unfavourable  rumours  were  the  chairman  did 
not  state,  except  that  they  were  "  spread  ap- 
parently by  an  official  of  the  company  on 
leave,"  who  was  not  a  technical  man.  Whe- 
ther the  official  was  a  technical  man  or  not, 
and  although  himself  unable  to  form  any 
opinion  of  the  prospects  of  the  company,  yet 
it  is  possible  that  his  information  would  be 
gained  from  other  company  officials,  some  of 
whom  would  be  technical  men.  From  the 
report  it  appears  that  the  grade  of  the  mine 
is  falling  off.  The  ore  reserve,  at  the  present 
time,  is  estimated  at  349,339  tons  of  an  aver- 
age value  of  about  14  dwt.,  as  against  398,466 
tons  averaging  16'8  dwt.,  the  estimated  figure 
given  in  the  previous  annual  report.  The 
value  of  the  ore  shows  therefore  a  decrease  of 
about  10s.  per  ton.  In  order  to  maintain  the 
usual  profit  with  an  ore  of  lower  grade,  it 
would  be  necessary  to  increase  the  crushing 
capacity  of  the  plant.  This  would  seem  to 
be  the  policy  adopted,  as  a  tube-mill  has  been 
erected,  and  with  the  new  electric  power-sta- 
tion, an  increase  in  the  scale  of  operations 
may  be  expected,  unless  the  shortage  of  native 
labour  prevents  it  for  the  time.  So  far  the 
result  of  a  shortage  of  native  labour  has  been 
to  decrease  the  rate  of  development.  The 
management  of  the  property  is  in  the  hands 
of  S.  C.  Aimetti. 

Labour.  —  The  reduction  of  the  working 
costs  and  a  sufficient  supply  of  efficient  labour 
are  inter-dependent  at  the  present  time.  The 
increasing  high  wages  paid  to  the  native  on 
the  Rand  is  directly  causing  the  shortage  of 
labour,  as  the  Kaffir  can  afford  to  work  for  a 
shorter  period  and  spend  more  time  at  home. 
The  high  cost  of  labour  is  militating  against  a 
reduction  in  the  working  cost,  even  where  in- 
tricate mechanical  appliances  are  introduced 
to  lessen  the  number  of  labourers  required. 
The  tendency  is  for  native  labour  to  go  to  the 
highest  bidder.  The  Witwatersrand  Native 
Labour  Association,  recruiting  natives  chiefly 
from  Portuguese  East  Africa,  and  the  recruit- 
ing agencies  of  the  various  groups  cannot  ob- 
tain an  adequate  supply.    A  field  has  thus  be- 


421 


422 


THE    MINING    MAGAZINE 


come  opened  for  the  private  recruiter,  who  in 
most  cases  is  a  contractor  and,  as  such,  takes, 
for  example,  a  contract  to  do  the  shoveUing 
and  tramming  on  a  mine,  at  a  fixed  price  per 
ton  or  per  truck,  a  certain  proportion  of  the 
price  paid  going  to  the  native  and  the  rest 
going  to  the  contractor.  The  contractor  sup- 
pHes  his  own  labour,  as  well  as  the  candles 
and  other  stores  required.  The  result  is  that 
both  the  contractors  and  their  labourers  will 
work  wherever  the  best  terms  are  granted. 
To  obtain  the  necessary  unskilled  labour,  one 
mine  has  only  to  pay  a  higher  price  for  under- 
ground work  than  another,  in  order  to  obtain 
a  transference  of  workers.  At  present  about 
10%  of  the  natives  are  in  the  employ  of  con- 
tractors, whose  natives  are  earning  a  much 
higher  wage  than  those  of  other  recruiting 
agencies.  As  the  percentage  of  contractor- 
natives  increases,  the  average  rate  of  native 
pay  will  increase  also,  with  the  result  that  the 
cost  of  unskilled  labour  will  eventually  become 
prohibitive  to  any  but  the  highest-grade  pro- 
perties. Mines  working  at  a  narrow  margin 
of  profit  will  be  frozen  out  of  the  labour  mar- 
ket. Apart  from  the  question  of  increased 
labour-cost,  the  amount  of  control  held  by  the 
contractors  over  the  mining  industry  is  an  im- 
portant consideration,  as  a  strike  by  the  con- 
tractors for  higher  prices  would  temporarily 
cripple  the  entire  industry. 

The  Rand  Klip  is  a  mine  situated  in  the 
far  east  Rand,  where  the  Witvvatersrand  for- 
mation, consisting  of  the  gold-bearing  con- 
glomerates and  quartzites,  is  overlain  by  the 
Transvaal  system,  consistingof  dolomite,  clay- 
slate,  shale,  and  sheets  of  interstratified  dia- 
base, the  whole  containing  large  quantities  of 
water.  The  Witwatersrand  formation, through 
which  the  majority  of  the  shafts  sunk  on  the 
Rand  pass  throughout  their  depth,  affords  good 
ground  for  sinking.  On  the  other  hand,  the 
strata  of  the  Transvaal  system,  containing 
large  volumes  of  water,  are  bad  for  sinking. 
The  difficulties  to  be  overcome  in  sinking  rec- 
tangular shafts  through  this  kind  of  bad  ground 
at  the  Rand  Klip  will  repay  consideration. 
During  the  past  12  months,  220  ft.  was  sunk 
in  the  west  shaft,  which  was  stopped  last 
January,  and  418  ft.  was  sunk  in  the  east  shaft, 
a  total  of  638  feet,  costing  ^50,331,  or  about 
£19  per  foot.  Costly  experience  on  the  Rand 
has  led  to  the  practice  of  hoisting  m  the  shafts 
from  one  point  only.  This  being  so,  either 
rectangular  or  circular  shafts  will  answer  the 
purpose.  A  circular  shaft  is  preferable  for 
several  reasons.  In  a  circular  shaft  either 
the  trucks  can  be  hoisted  in  cages  or  self- 


dumping  skips  used.  Where  bad  ground, 
containing  large  quantities  of  water,  has  to 
be  penetrated,  a  circular  shaft  can  be  more 
easily  put  down  and  lined  with  cast-iron  tub- 
bing or  the  system  of  bricking  known  as  '  cof- 
fering,' in  such  a  way  that  practically  all  water 
can  be  prevented  from  entering  the  shaft,  ob- 
viating expensive  pumping  arrangements.  In 
addition,  future  trouble  due  to  the  decay  of 
timber  in  rectangular  shafts  is  eliminated. 

The  Nissen  Stamp  was  the  subject  of  a 
paper  entitled  '  Notes  on  High-Duty  Gravity 
Stamp- Mills,'  by  Peter  N.  Nissen,  read  before 
the  Chemical,  Metallurgical,  &  Mining  Society 
of  South  Africa  at  the  October  meeting.  In 
this  paper  the  author  makes  out  a  strong  case 
in  favour  of  the  Nissen  stamp,  as  against  the 
old  arrangement  of  five  stamps  working  in  one 
mortar-box.  Theoretically  it  is  natural  to  ex- 
pect a  stamp  of  the  Nissen  type,  running  in  its 
own  mortar-box,  to  crush  more  ore,  in  a  given 
time,  than  any  one  stamp  in  a  5-stamp  mortar- 
box.  The  Nissen  stamp  necessarily  falls  upon 
an  even  layer  of  ore  lying  on  the  die,  whereas 
it  is  easily  understood  that  when  five  stamps 
are  falHng  in  quick  succession  in  the  same 
mortar-box,  a  wave  motion  of  the  pulp  is  set 
up  and  stamps  may  drop  upon  the  dies  with- 
out doing  useful  work.  Apart  from  tnis,  the 
Nissen  stamp  working  in  its  own  mortar-box 
has  a  larger  relative  screen-area  than  is  af- 
forded by  a  multiple-stamp  mortar-box  of  the 
single-screen  type.  Mr.  Nissen  very  truly 
states  that  the  efficiency  of  the  gravity  stamp- 
mill  depends  "  in  a  great  measure  upon  the 
skilled  attention  devoted  to  it."  He  also  states 
that  in  large  installations  of  Nissen  stamps  it 
has  been  possible  to  obtain  an  actual  running 
time  of  over  95%  of  the  total  possible  time. 
This  is  no  improvement  over  the  old  installa- 
tion, where  five  stamps  are  running  in  each 
mortar-box,  since  the  Ferreira  stamp-mill  of 
120  stamps,  in  the  year  1910,  headed  the  list 
with  an  actual  running  time  of  3537  days  or 
about  97%  of  the  total  possible  time.  "  Ex- 
haustive tests  have  been  carried  out,  with 
Nissen  stamps  at  2000  lb.  dropping  weight, 
at  the  reduction  works  of  the  City  Deep,  in 
connection  with  tests  made  simultaneously 
with  a  10-stamp  battery  of  City  Deep  type." 
The  results  obtamed  were  in  favour  of  the 
Nissen  stamp.  With  a  f  in.  screen,  the  ton- 
nage crushed  per  stamp  per  day  for  Nissen 
stamps  was  36'69  to  3774  tons,  and  for  City 
Deep  stamps  2272  to  24'34  tons.  The  power 
consumption  per  ton  of  ore  crushed  varied 
from  27  to  4  hp. -hours  for  Nissen  stamps, 
and  from  4'45  to  5'5  hp. -hours  for  City  Deep 


DECEMBER,    1911 


423 


stamps.  From  the  tests  conducted  at  the  City 
Deep,  the  efficiency  of  the  Nissen  stamps  was 
found  to  be  30%  higher  than  that  of  the  heavy 
type  of  ordinary  stamp.  The  battery  in 
which  the  4  Nissen  stamps  were  mounted 
was  one  in  which  10  ordinary  stamps  had 
been  before,  and  probably  the  comparison  be- 
tween the  two  types  was  therefore  not  quite 
representative,  for  the  Nissen  would  appar- 
ently not  require  such  heavy  foundations  and 
the  width  of  the  frame  for  the  4  stamps  could 
easily  be  less.  [An  abstract  of  Mr.  Nissen's 
paper  appears  in  our  Precis  of  Technology. 
— Editor]  . 

Power-plant.  —  The  Rosherville  power- 
station,    owned   by    the   Rand  Mines  Power 


pumps  are  also  of  the  centrifugal  type,  and 
are  driven  by  steam-turbines,  which  exhaust 
into  the  low-pressure  cylinders  of  the  main 
turbines.  Duff  coal  is  supplied  to  the  boilers 
from  small  bunkers  arranged  above  the  firing- 
floors.  The  main  turbines,  driving  the  gene- 
rators, to  which  they  are  direct-coupled,  run 
at  1000  rev.  per  min.  The  generators  deliver 
a  3-phase  current  at  a  frequency  of  50  periods 
per  second  and  at  a  pressure  of  5000  volts  at 
the  machine  terminals.  There  are  in  all  5 
A. E.G.  turbo-generators  each  of  12,000  kilo- 
watt capacity.  The  air-compressors  of  the 
rotary  type  are  driven  by  direct-coupled  tur- 
bines running  at  3000  rev.  per  min.  and  are 
capable  of  converting  590  cubic  metres  of  free 


CYANIDE  PLANT  OF  THE  ROODEPOORT   UNITED  MAIN   REEF  MINE. 


Supply  Co.,  and  run  by  the  Victoria  Falls 
Power  Co.,  is  one  of  the  largest  and  most  up- 
to-date  of  its  kind.  A  noteworthy  point  is  the 
complete  absence  of  the  old  reciprocating  type 
of  engine.  Everything  is  driven  by  steam- 
turbines.  Steam  is  supplied  by  24  Babcock 
&  Wilcox  water-tube  boilers,  each  capable  of 
evaporating  30,0001b.  water  per  hour,  to  steam 
at  a  pressure  of  220  lb.  per  sq.  in.  and  a  tem- 
perature of  350°C.  The  boilers  are  fitted  with 
superheaters,  chain-grate  stokers,  and  Pratt's 
system  of  induced  draft,  which  works  on  the 
injector  principle.  The  boiler-feed  water  is 
supplied  by  turbine-driven  centrifugal  pumps. 
The    condenser    air  -  pumps   and    circulating 


air  per  minute  to  an  absolute  pressure  of  9  at- 
mospheres. The  compressors,  which  are  multi- 
stage, are  divided  into  high  and  low-pressure 
cylinders,  with  inter-stage  coolers.  There  are 
4  A. E.G.  turbo-air  compressors.  The  electric 
current  at  5000  volts  pressure  is  passed  through 
transformers  and  is  supplied  at  two  pressures, 
namely,  20,000  volts  through  underground 
cables  and  40,000  volts  by  overhead  lines. 
The  whole  plant,  which  has  only  been  run- 
ning for  a  short  time,  is  doing  well ;  although 
stoppages  occur,  it  is  hoped  that,  after  a  time 
these  may  be  reduced  to  a  minimum.  The 
electric  power  is  supplied  at  a  cost  of  0'5617 
penny  per  unit,  plus  2%  for  transformer-losses. 


424 


THE    MINING    MAGAZINE 


CAMBORNE. 
Goss  Moor.  —  The  working  of  the  first 
'  paddock  '  has  resulted  in  a  profit  being  made, 
but  the  expenses  were  exceptionally  heavy 
owing  to  the  initial  difficulties  inherent  to  a 
new  plant  and  to  the  inexperience  of  the 
workmen.  The  cost  of  treatment  per  cubic 
yard  of  gravel  has  so  far  been  about  Is.,  but 
Mr.  Lush  anticipates  reducing  this  figure  by 
nearly  one-half  when  everything  is  running 
smoothly.  If  his  forecast  proves  correct,  a 
handsome  profit  should  be  shown  in  the  near 
future.  The  black  tin  produced  from  this  pro- 
perty is  exceptionally  good,  the  percentage  of 
metal  varying  from  73  to  75% ;  and  although 
that  percentage  is  only  slightly  higher  than  the 
first-grade  parcels  sold  by  some  of  the  mines, 
yet  the  quality  of  the  tin  is  much  better.  Quite 
recently  several  tons  realized  /^135  per  ton. 

Great  Dowgas. — This  property,  situated 
at  St.  Stephens  in  Brannel,  on  which  it  is 
stated  ^"60,000  has  been  spent,  is  now  being 
offered  for  sale  by  the  receiver  for  the  deben- 
ture-holders. The  surface  equipment  gener- 
ally is  excellent  and  the  battery  and  dressing 
plant  have  a  capacity  of  100  tons  per  day. 
This  is  yet  another  of  those  lamentable  ex- 
amples of  erecting  a  dressing  plant  before  the 
developments  warranted  such  expenditure ; 
but  now  that  the  money  has  been  spent,  an 
excellent  opportunity  presents  itself  to  anyone 
willing  to  put  up  money  to  develop  vigorously 
the  property,  for  it  is  one  situated  in  a  good 
district,  and  fully  deserving  a  proper  trial. 

St.  Ives  Consolidated. — This  company  is 
in  want  of  further  funds  to  develop  the  St. 
Ives  Consols  and  Giew  mines  and  to  equip 
the  former  with  a  mill  and  dressing  plant.  An 
issue  of  ;^1 20,000  6%  first  debentures  has  been 
authorized.  William  Thomas,  of  Camborne, 
has  recently  made  an  inspection  of  the  proper- 
ties ;  he  reports  that  the  St.  Ives  Consols  mine 
has  been  drained  to  the  77-fm.  level  and  he 
estimates  that  the  ore  reserve  available  is  fully 
50,000  tons  of  an  average  value  of  23  lb.  of  tin 
oxide  per  ton,  or  just  over  1%.  At  Giew,  the 
eastern  portion  of  the  mine  has  been  drained  to 
the  122-fm.  level  in  Frank's  shaft,  and  here 
too,  extensive  blocksof  low-gradeore  are  avail- 
able, which  he  estimates  at  a  further  50,000 
tons  of  1%  stufif,  although  the  local  manager 
figures  on  52,000  tons  of  an  average  assay - 
value  of  20'5  lb.  black  tin  per  ton.  Mr.  Thomas 
concurs  with  the  recommendation  of  the  con- 
sulting engineer,  F.  Dietzsch,  to  erect  a  40- 
stamp  battery  at  St.  Ives  Consols  working  on 
the  principle  of  graduated  crushing  by  the  addi- 
tion of  tube-mills  and  ball-mills. 


South  Crofty. — The  working  of  this  mine 
for  the  first   10  months  of  the  current  year 
shows  a  clear  profit  of  10s.  per  ton  milled,  as- 
suming the  cost  to  be  no  higher  than  in  1910, 
namely,  21s.  6d.  per  ton  milled,  which  figure 
includes  depreciation,  royalties,  and  all  head- 
office  charges.     For  the  period  in  question, 
52,736  tons  of  ore  has  been  milled,  producing 
687i  tons  of  tin  and  wolfram,  or  a  recovery 
of  about  29  lb.  per  ton,  while  the  total  value  of 
the  products,  including  arsenic,  was  ^83,276, 
or  31s.  7d.  per  ton  handled.     For  1910,  the  re- 
covery of  tin  and  wolfram  was  27'8  lb.  per  ton, 
so  that  the  increased  profit  is  largely  due  to  the 
higher  prices  realized  for  the  products.    With 
an  improved  recovery  of  slightly  over  1  lb.  of 
tin  and  wolfram  per  ton  (there  being  little  in- 
crease in  the  value  of  the  arsenic  sold),  the 
monetary  value  of  each  ton  of  ore  milled  has 
jumped  from  25s.  6d.  in  1910  to  31s.  7d.  for 
the  first  ten  months  of  this  year.    The  develop- 
ment footage  continues  about  the  same  ;  4053 
feet  was  developed  or  one  foot  for  each  13  tons 
of  ore  sent  to  the  stamps,  which  is  a  fair  rate 
considering  the  width  of  the  lodes. 

Dolcoath. — The  interim  dividend  recently 
declared  by  the  directors,  of  Is.  per  share,  free 
of  income  tax,  on  account  of  the  profits  for 
the  current  six  months,  absorbing  ^17,000, 
makes  it  quite  evident  that  the  working  cost 
at  the  premier  mine  of  the  county  has  been 
materially  reduced,  for  otherwise  a  profit  to 
justify  such  a  dividend  would  be  out  of  the 
question.  For  the  19  weeks  ended  November 
11,  34,495  tons  of  ore  was  crushed,  producing 
636  tons  8  cwt.  of  black  tin,  which  realized 
;^74,355.  The  recovery  is  equal  to  41*3  lb. 
per  ton,  and  the  recovery  per  ton  was  worth 
43s.  Id.  or  slightly  over  Is.  per  lb.  For  the  six 
months  ended  June  30  last  the  recovery  was 
47'38  lb.  per  ton  milled  and  the  value  49s.  7d., 
so  that  the  monetary  value  has  fallen  6s.  6d. 
per  ton.  The  working  cost  for  the  previous 
six  months,  including  depreciation,  but  exclud- 
ing income  tax,  which  is  only  charged  once  a 
year,  was  close  to  34s.  6d.  per  ton.  If  the  work- 
ing cost  for  the  current  half-year  is  taken  at 
this  figure,  the  profit  for  the  first  19  weeks 
would  be  ;^14,800,  or  8s.  7d.  per  ton,  but  seeing 
that  the  dividend  declared  absorbs  £' 17,000,  it 
must  be  obvious  that  the  manager's  anticipa- 
tions of  a  reduced  working  cost,  resulting  from 
the  completion  and  use  of  the  Williams  shaft, 
of  the  approved  stamping  arrangements,  and 
the  many  surface  improvements,  have  been 
fulfilled. 

From  a  recent  Home  Office  report,  it  ap- 
pears that  Dolcoath,  as  might  have  been  ex- 


DECEMBER,    1911 


425 


pected  from  the  interest  shown  by  R.  A. 
Thomas  in  the  health  of  the  miners,  has  taken 
the  lead  in  the  provision  of  baths  for  the  men. 
The  bath-rooms  are  7  ft.  6  in.  by  5  ft.  6  in., 
and  each  is  partitioned  off  and  fitted  with  an 
enamelled  bath,  hot  and  cold  water  being  pro- 
vided. For  a  preliminary  washmg  of  the  hands 
and  face,  basins  have  been  installed.  It  ap- 
pears that  on  an  average  the  men  have  a  bath 
once  a  week,  but  they  may  have  one  daily  if 
they  so  choose. 


^ 

jJH^H 

"^^^^^^m;'  ■■■■. 

-rf'J-                                            — 

o                          ^                       •                                  _               - 

Hobinson  Shaft,  South  Crofty. 

Labour-Unions. —  It  is  common  knov/ledge 
that  labour-unions  have  not  in  the  past  been 
regarded  with  any  favourable  eye  by  the  min- 
ers and  clay-workers  of  Cornwall,  all  efforts 
to  organize  the  men  having  resulted  in  miser- 
able failure.  Now,  however,  it  appears  that 
the  Workers'  Union,  in  consequence  of  an 
active  crusade,  is  getting  a  hold  on  the  clay- 
workers  of  Mid-Cornwall,  and  an  extension  of 
the  movement  to  the  Mining  Division  is  pro- 
mised in  the  near  future.  The  bait  held  out 
to  the  clay- workers  is  a  minimum  wage  of  30s. 
as  against  about  20s.  per  week.  There  can  be 
no  question,  considering  the  prosperity  of  the 
china-clay  industry,  that  the  wage  of  the  aver- 


age worker  is  inadequate  and  miserably  small, 
and  with  the  advance  in  the  cost  of  living,  the 
men  are  justified  in  expecting  a  higher  rate  of 
pay,  but  the  50%  increase,  which  is  the  ultimate 
aim  of  the  Workers'  Union,  is  quite  out  of  the 
question.  It  would  be  a  wise  move  on  the  part 
of  the  proprietors  to  anticipate  the  growing 
irritation  of  the  men  by  advancing  wages, 
and  this  too  would  be  the  best  plan  to  coun- 
teract the  wiles  of  the  Union  officials.  It 
is  to  be  hoped  that  the  miners  too  will  not  be 
led  into  any  agitation  for  an  increased  mini- 
mum wage  irrespective  of  work  done.  Owing 
to  the  increase  of  men  on  day's  pay,  the  possi- 
bility is  certainly  not  so  remote  as  formerly, 
if  a  really  well  organized  effort  were  made  to 
enrol  the  men  in  the  Union.  But  with  so  few 
of  our  mines  making  profits  at  the  present  high 
prices,  any  such  agitation  would  be  most  inop- 
portune, and  if  successful,  could  only  result  in 
the  shutting-down  of  some  of  the  concerns  that 
are  now  struggling  to  make  both  ends  meet. 

SAN  FRANCISCO. 

Interest  in  Mining  upon  the  Mother  Lode 
has  been  much  stimulated  by  the  transfer 
of  the  Old  Plymouth  Consolidated  mine,  in 
Amador  county,  to  Bewick,  Moreing  &  Co., 
late  in  October.  The  mine  has  been  idle  for 
nine  years,  and  is  now  full  of  water.  The  pro- 
perty, which  was  worked  continuously  until 
1888,  is  reported  to  have  made  a  total  produc- 
tion of  .$6,500,000  and  was  a  consolidation  of 
the  Empire,  Amador  Pacific,  and  Plymouth 
mines.  It  was  equipped  with  two  80-stamp 
mills,  one  having  750-lb.  stamps  and  the  other 
1000-lb.  stamps,  driven  by  hydraulic  power. 
The  average  yield  of  the  ore  in  1886  was 
$6' 18  per  ton,  and  Sy59  per  ton  in  1887,  the 
working  cost  being  given  as  $3'07.  The  con- 
centrate averaged  li%,  and  is  reported  to  have 
had  a  gross  value  of  over  ;^100  per  ton.  It 
was  treated  at  the  chlorination  works  of  the 
company  at  a  cost  of  ^13'40  per  ton  of  con- 
centrate. The  vein  was  40  to  70  ft.  wide  and 
dipped  57°  to  the  east.  The  main  ore-shoot 
was  400  ft.  long.  The  mine  was  opened  by 
three  inclined  shafts  and  one  vertical  3-com- 
partment  shaft  1700  ft.  deep  ;  it  was  compara- 
tively dry  and  buckets  were  used  for  bailing. 
In  1888  a  fire  broke  out  in  the  mine  between 
the  Pacific  and  South  Empire  shafts,  and  was 
only  extinguished  by  sealing  up  the  mouths  of 
all  the  shafts.  When  the  mine  was  re-opened, 
it  was  found  that  the  workings  had  collapsed 
in  several  places  and  after  a  small  amount  of 
desultory  work,  it  was  finally  closed  in  Octo- 
ber 1892.     Albert  Burch  is  the  local  repre- 


426 


THE    MINING    MAGAZINE 


sentative  for  Bewick,  Moreing  &  Co.  and  the 
work  of  development  is  already  under  way. 
The  results  will  be  awaited  with  much  interest. 
Another  old  mine  that  will  probably  soon 
be  re-opened  is  the  Princeton,  in  Mariposa 
county.  This  is  reported  to  have  produced 
over  $5,000,000  and  has  been  worked  to  a 
depth  of  1250  ft.  (vertical)  though  the  larger 
part  of  the  production  came  from  above  the 
600-ft.  level.  The  chances  that  both  of  these 
mines  can  be  developed  into  large  and  profit- 
able producers  are  generally  regarded  as  ex- 
cellent. 

At  the  App  mine,  at  Quartz,  in  Tuolumne 
county,  the  surface  of  the  Heslop  claim  col- 
lapsed (on  October  28)  over  an  area  150  by 
200  ft.  The  penstock  to  the  mill  was  broken, 
but  little  other  damage  was  done,  though  the 
caving  (due  to  insufficient  timbering)  extended 
through  to  the  300-ft.  level. 

Dredge  No.  8  of  the  Natomas  Consolidated 
was  destroyed  by  a  fire  on  October  20.  This 
dredge  and  Natoma  9  are  peculiar  in  utilizing 
electric  current  at  2000  volts.  The  fire  ap- 
pears to  have  started  in  an  oil-switch  (not 
transformer),  and  as  soon  as  it  was  realized 
that  it  was  beyond  control  the  sea- valves  were 
opened  with  the  intention  of  sinking  the  boat. 
Unfortunately  the  digging-ladder  prevented 
the  bow  from  sinking,  and  the  accumulated 
tailing  prevented  the  submergence  of  the  stern. 
The  part  that  remained  above  the  water  was 
completely  destroyed,  but  some  of  the  machin- 
ery will  undoubtedly  be  salvaged.  The  cost 
of  the  dredge  is  given  as  $250,000  and  it  was 
insured  for  about  f  of  that  sum. 

The  report  of  the  Utah  Copper  Co.  for  the 
quarter  ended  September  30  shows  an  increase 
in  production,  as  was  anticipated,  and  the  low- 
est cost  per  pound  in  the  history  of  the  com- 
pany.    The  output  for  the  three  months  was 
25,85 1,4561b.,  as  compared  with  25,469,8121b. 
for  the  previous  quarter  and  21,296,709  lb.  for 
the  first  threemonths  of  theyear.  The  netaver- 
agecost  for  the  quarter,  after  deducting  smelter 
allowances  and  without  crediting  miscellaneous 
income,  was7'56c.  per  pound,  while  in  Septem- 
ber it  was  reduced  to  7' 18c.  for  the  monthly 
average.  The  cost  during  the  previous  quarter 
averaged  8'02c.  per  pound.  Thecompanymade 
a  net  profit  for  the  quarter  of  $1,538,712,  in- 
cluding $375,187  Nevada  Consolidated  divi- 
dends. It  paid  $  1 ,  177,0 1 2  dividends  and  added 
$361,700  to  surplus.    The  ore  handled  showed 
a  falling  off  in  grade,  being  1*4829%  copper, 
as  compared  with  1'6332%  copper  for  the  pre- 
vious quarter.  The  tonnage  was  increased  from 
1,060,414  to  1,273,373.     The  earnings  for  the 


quarter  were  $361,700  over  the  dividend  re- 
quirements, corresponding  to  a  surplus  over 
dividends  of  $554,000  for  the  first  nine  months 
of  the  year. 

MEXICO. 

Restoration  of  Order.  —  Francisco  I. 
Madero,  leader  of  the  revolution  that  over- 
threw the  Diaz  government  and  now  presi- 
dent of  Mexico,  has  announced  his  intention 
of  taking  energetic  action  for  the  complete 
pacification  of  the  country.  He  states  that 
bandits  and  those  who  rise  in  arms  against 
the  general  government  will  be  crushed  with 
an  iron  hand.  He  has  ordered  a  vigorous 
campaign  against  Zapatistas  in  the  State  of 
Morelos,  and  has  sent  a  force  of  federals  to 
crush  an  uprising  in  Oaxaca.  The  Chamber 
of  Deputies  has  passed  a  bill  appropriating 
14,000,000  pesos  for  increases  in  the  army, 
the  greater  part  of  the  money  to  be  spent  in 
the  organization  of  additional  regiments  of 
rurales.  When  the  provisions  of  the  mea- 
sures are  carried  out,  there  will  be  60  regi- 
ments of  rurales  in  the  service  of  the  Mexi- 
can government.  Conditions  still  are  un- 
settled, and  some  fears  for  the  immediate 
future  are  entertained.  Gen.  Bernardo  Reyes, 
now  at  San  Antonio,  Texas,  is  believed  to  be 
planning  a  revolution  against  the  Madero 
government,  and  his  movements  are  being 
watched  by  secret-service  men  of  both  the 
American  and  Mexican  governments.  The 
American  government  is  taking  steps  again 
to  patrol  the  border  effectively.  In  Torreon 
several  thousand  workmen  are  on  srrike,  the 
number  including  the  employees  of  the  Tor- 
reon smelter,  which  is  controlled  by  the  Ma- 
dero interest.  The  strikers  demand  increased 
pay  and  an  8-hour  day.  The  city  has  been 
placed  under  martial  law.  It  is  feared  that 
workmen  in  other  districts  will  follow  this 
bad  example. 

New  Railroads. — The  Southern    Pacific 
has  commenced  surveys  for  a  line  from  Gua- 
dalajara to   Mexico  city.     A   concession  for 
such  a  line  was  granted  by  the  Diaz  govern- 
ment.     The    West    Coast    extension   of  the 
Southern  Pacific  will  be  completed  to  Tepic, 
capital  of  the  territory  of  the  same  name,  in 
December,  and  it  is  announced  that  there  will 
be  as  little  delay  as  possible  in  building  the 
link  between  Tepic  and  Guadalajara.     The 
National  Railways  of  Mexico  recently  bor- 
rowed $13,000,000  from  New  York  bankers, 
and  a  part  of  the  money  will  be  devoted  to 
the    proposed  Tampico-Veracruz  and  Tam- 
pico- Mexico  City  lines.     The  Tampico-Vera- 


DECEMBER,    1911 


427 


cruz  line  will  traverse  the  oil  belt  of  the  State 
of  Veracruz,  where  there  has  been  great  oil 
development  during  the  last  18  months,  and 
will  also  open  a  rich  agricultural  territory. 
A  branch  will  be  built  to  connect  with  one  of 
the  National  lines  in  the  State  of  Hidalgo, 
thereby  establishing  a  short  route  between 
Tampico  and  Mexico  City.  Work  on  the 
Durango-Cahitas  line  of  the  National,  which 
has  been  delayed  by  a  shortage  of  money  for 
construction,  is  to  be  pushed  This  line  will 
open  the  Sombrerete,  Nieves,  and  other  min- 
ing districts.  The  Mexico  Northwestern  Rail- 
way is  operating  trains  on  the  recently  com- 
pleted branch  that  gives  facilities  of  trans- 
port to  the  Cusihuiriachic  silver  district  of 
Chihuahua. 


I  want  to  keep  Mexico  out  of  reach  of  the 
golden  arms  of  the  ferocious  octopus."  The 
bill  provides  for  taxing  oil  land,  as  mineral 
land  now  is  taxed,  and  provides  for  a  tax  on 
all  oil  exported  from  Mexico.  Recently  there 
have  been  reports  of  negotiations  between  the 
Pearson  interests  and  the  Standard  Oil. 

Smelting  Resumed.  —  The  Chihuahua 
smelter  of  the  American  Smelting  &  Refining 
Co.,  which  was  closed  several  months  ago  as 
a  result  of  disturbed  labour  conditions  follow- 
ing the  revolution,  is  again  in  operation.  The 
company  will  build  two  additional  furnaces  at 
this  plant,  giving  it  a  capacity  of  from  900  to 
1000  tons  daily.  Smelting  also  has  been  re- 
sumed at  the  600-ton  copper  smelter  of  the 
Rio  Tinto  Copper  Co.  at  Terrazas,  in  Chihua- 


.W'^'^'^^ 


^•^^ 


.JC 


MADERO'H  TROOPS  ON  THEIR  WAY  TO  THE  REFUGIO  MINE,  AT  SALINAS. 


Oil. — A  bill  placing  oil  land  on  the  same 
basis  as  mineral  land,  giving  every  one  the 
right  of  prospecting  and  denouncing,  has 
been  introduced  in  the  Chamber  of  Deputies 
by  Congressman  Jose  Maria  Lozano.  The 
bill  seeks  to  guard  against  monopolistic 
control  by  the  purchase  of  oil  land,  as  is  pos- 
sible under  the  existing  laws.  At  the  in- 
troduction of  the  bill  Congressman  Lozano 
said:  "  A  sale  of  the  Pearson  oil  interests 
to  the  Standard  Oil  is  now  pending,  and 
if  we  do  not  pass  this  bill  a  time  will 
come  when  the  old  Viceroy's  palace  and 
the  castle  of  Chapultepec  will  be  ruled  from 
Wall  Street,  as  the  Standard  Oil  money 
will  buy  the  votes,  the  magistrates,  the  courts, 
the  deputies,  the  senators,  and  the  presidents. 


hua,  which  likewise  was  closed  some  time  ago 
as  a  result  of  disturbed  conditions.  The  Rio 
Tinto  is  controlled  by  Cleveland  interests. 

Mololoa. — This  famous  old  mine,  in  the 
Hostotipaquillo  district  of  Jalisco,  is  again 
producing  rich  ore,  and  shipments  are  being 
made  regularly  to  the  Aguascalientes  smelter 
of  the  American  Smelting  &  Refining  Co.  Two 
hundred  pack-mules  are  on  the  road  between 
the  mine  and  the  Southern  Pacific  Station  at 
Magdalena.  The  Mololoa  is  now  the  property 
of  the  Mololoa  Mining  Co.,  of  New  York, 
which  purchased  it  early  this  year.  It  for- 
merly was  owned  by  the  Mololoa  syndicate 
of  Toronto,  Canada.  Recent  development 
has  shown  that  the  Canadian  concern  was 
within  30  ft.  of  a  bonanza  when  work  was 


428 


THE    MINING    MAGAZINE 


stopped  because  of  lack  of  capital.  The  New 
York  company  will  build  a  reduction  plant 
during  the  coming  year,  a  big  tonnage  of 
high-grade  milling  ore  existing  in  the  old  and 
new  workings. 

Greene-Cananea. — The  October  produc- 
tion of  this  big  Cananea  concern  was  6,000,000 
pounds  of  copper,  the  largest  in  the  history  of 
the  Cananea  smelter.  About  one-third  of  the 
output  resulted  from  concentrate  from  the 
Miami  Copper  Co.,  which  are  sent  from  the 
United  States  to  Cananea  for  smelting.  It 
is  stated  that  the  production  cost  of  the 
Greene-Cananea  is  being  held  to  9  cents  per 
pound  of  copper. 

Dos  Cabezas. — Dr.  F.  S.  Pearson  and 
associates  will  build  a  stamp-mill  and  cyanide 
plant  at  their  Dos  Cabezas  mine,  60  miles 
west  of  Casas  Grandes,  in  Chihuahua.  The 
greater  part  of  the  reduction  machinery  has 
reached  the  property.  The  Dos  Cabezas  has 
been  producing  rich  ore  for  some  time  ;  a  re- 
cent shipment  of  27  tons  to  the  El  Paso  smel- 
ter netted  $  1 8,000.  The  Mexico  Northwestern 
railway,  which  is  controlled  by  the  Dr.  Pear- 
son interests,  recently  let  a  contract  for  a  47- 
kilometre  branch,  to  extend  from  Pearson  to 
Colonia  Pacheco.  This  branch  will  give  trans- 
port facilities  to  the  Dos  Cabezas. 

MELBOURNE. 

Mining  in  Australia  durmg  the  past 
month  has  been  uneventful.  The  truth  is 
that  the  people  generally  are  so  prosperous 
that  prospecting  has  been  almost  entirely  sus- 
pended in  order  that  labour  may  devote  itself 
to  the  more  lucrative  avocations  of  agriculture 
and  shearing.  This  condition  of  affairs  has 
prevailed  for  the  past  seven  years  and  is  re- 
flected in  the  declining  gold  yields  in  all  the 
states.  That  for  Victoria  has  sunk  to  432,000 
oz.  for  the  first  ten  months  of  the  current  year, 
a  shrinkage  of  50,000  oz.  as  against  the  corres- 
ponding term  in  1910.  The  other  States,  even 
though  they  do  not  disclose  much  decrease, 
have  the  shaky  appearance  that  presages  a 
fall.  It  is  evident  that  the  developments  in 
mining  for  the  future  must  come  from  the 
vast  belt  of  country  that  lies  inside  the  fringe 
of  settlement  around  the  coast.  Togo  inside 
that  fringe  means  exceedingly  hazardous  work 
and  for  the  moment  no  one  is  inclined  to  ac- 
cept the  risk.  When  times  become  hard  and 
labour  is  less  exacting,  then  prospecting  will 
be  resumed  and  Australian  mining  will  go 
ahead  again. 

In  North  Queensland  the  Mount  Elliott 
mine  has  given  a  record  yield  for  a  month. 


The  October  campaign  resulted  in  606  tons  of 
blister  copper  being  obtained.    This  is  the  best 
record  of  the  mine,  but  strange  to  say  it  was 
prefaced  by  a  substantial  drop  in  the  price  of 
the  shares.     This  is  ascribed  to  the  shortage 
of  labour  in  the  district  and  to  the  fact  that 
the  ore  in  the  bottom  level  is  not  developing 
satisfactorily.     Diamond-drilling  gives   little 
result.     A  new  claim,  the  Limestone,  in  Clon- 
curry,  has  been  acquired,  and  it  is  hoped  that 
this  property  will  revive  the  fortunes  of  the 
company.    The  old  estimates  of  £35  per  share 
strangely  compares  with  the  price  at  the  pre- 
sent time  which  is  practically  one-tenth  of  that 
value.     Great    expectations    continue*  to    be 
centred  on  the  Hampden  and  Duchess  mines 
belonging  to  the  Hampden  company.    A  large 
smelter  is   being   built,  and   when   this  is  in 
operation  a  livelier  market  for  the  shares  is 
expected  to  result,  due  to  the  better  working 
conditions  that  will  then    prevail.      By    that 
time  also  the  Duchess  mine  will  have  been 
linked  by  railway  with  the  Hampden,  and  the 
company's  new  claim,  the  Trekelano,  should 
also    be   supplying  a   quota    of    the    smelter 
charge.     All  the  same  the  feeling  is  that  it 
would  be  a  great  deal   better   if  the  Mount 
Elliott  with  its  substantial  cash  resources  and 
the    Hampden    with    its   orebodies  could    be 
consolidated  into  one  property  with  a  central 
concentration  plant.     There  seems  to  be  some 
jealousy  over  the  solving  of  this  problem,  but 
the  difficulties  may  be  overcome  and  a  fine 
mineral  district  of  great  extent  helped  by  such 
a  combination. 

Broken  Hill. — So  far  the  British  Broken 
Hill  mine  has  failed  to  locate  the  upward  con- 
tinuation above  200  ft.  of  the  big  shoot  of  ore 
discovered  at  Thompson's  shaft.  The  orebody 
may  have  turned  away  flatly  to  the  south,  and 
if  so  the  delay  in  picking  up  the  lode  can  be 
easily  understood.  Boring  has  been  carried 
out  on  a  large  scale  to  find  the  shoot  of  ore  in 
that  direction.  The  company  has  declared  a 
dividend  of  2s.  per  share  from  profits  made 
partly  out  of  mining  work  and  partly  out  of 
the  sale  of  slime  to  the  Junction  North. 
The  Labour  Strike  at  Mount  Lyell  con- 
tinues. It  constitutes  one  of  the  most  inter- 
esting labour  ebullitions  south  of  the  equator. 
The  attitude  of  the  mine  employees  in  uphold- 
ing the  case  of  Norman  White  who  went  into 
the  mine  to  terrorize  two  contractors  into  ad- 
mitting that  they  had  been  working  more  than 
eight-hour  shifts  has  created  a  bad  impression, 
for  it  is  taken  that  the  real  motive  of  the  leaders 
was  to  claim  for  themselves  as  Union  officials 
the  right  to  go  anywhere  they  like  in  the  pro- 


DECEMBER,    1911 


429 


perty.  As  the  Lyell  Blocks  next  door  is  trying 
to  pick  up  the  shoot  of  ore  supposed  to  under- 
lie from  the  North  Lyell  into  the  Lyell  Blocks, 
it  can  be  seen  how  detrimental  to  the  company, 
even  from  the  standpoint  of  hard  business  con- 
siderations, it  would  be  to  allow  men  not  under 
the  discipline  of  the  company  to  go  wherever 
they  please  in  such  a  claim  as  the  North 
Lyell.  This  by  no  means  indicates  that  the 
Lyell  Blocks  is  likely  to  pick  up  the  North 
Lyell  shoot  of  ore,  and  I  only  mention  the 
matter  to  show  how  from  a  working  stand- 
point no  management  could  concede  to  an 
irresponsible  body  of  trade  unionists  the  right 
to  move  about  where  they  like  in  a  mine  at 
their  own  sweet  will.  The  present  position  is 
that  the  man  Norman  White  is  likely  to  be 
thrown  over-board  by  the  unionists,  and  the 
company  may  agree,  in  order  to  retain  workers 
at  Mount  Lyell,  to  discuss  the  question  of  an 
increased  wage  to  its  employees.  Looking  at 
the  profits  for  the  past  twelve  months  it  seems 
difficult  to  see  how  the  board  can  afford  to 
give  any  great  increase  in  wages,  unless  the 
price  of  copper  improves.  With  this  fact 
staring  the  public  in  the  face,  the  general  im- 
pression prevails  that  the  strike  is  not  so  near 
settlement  as  some  people  estimate  unless  the 
men  can  be  brought  to  realize  the  exact  posi- 
tion of  affairs. 

Northern  Territory.  —  A  great  deal  of 
amusement  has  been  caused  by  the  receipt 
here  of  a  circular  telling  of  the  coming  boom 
in  '  Northern  Terrors.'  When  we  in  Australia 
are  informed  that  the  Northern  Territory  is 
the  richest  goldfield  in  the  world,  we  only  wish 
to  goodness  that  such  was  the  case.  If  that 
were  so,  then,  instead  of  the  Australian  gold 
yield  dwindling,  it  would  be  on  the  up-grade, 
and  we  should  have  a  greater  output  of  the 
precious  metal  than  is  produced  at  present  on 
the  Rand.  The  statement  that  Palmerstown 
is  the  principal  town  is  a  bit  of  geographical 
news  to  people  who  had  hitherto  ascribed  that 
honour  to  Port  Darwin.  It  is  not  generally 
known  that  one  of  the  largest  holders  of  town 
properties  there  is  Lord  Rosebery,  and  that 
the  Federal  Land  Tax  has  been  specially  de- 
signed to  reach  absentee  squatters  of  his  type. 
Allowing  that  all  the  figures  given  in  the 
circular  respecting  the  output  from  the  pro- 
perties held  in  the  Northern  Territory  gold- 
fields  be  perfectly  true,  even  then  they  only 
represent  scratchings.  It  would  beaslur  on  the 
mining  intelligence  of  Australians  who  have 
dipped  pretty  deeply  into  Northern  Territory 
shows  in  the  past  if  they  were  proved  to  have 
neglected    the    wonderful    resources   of    that 


country.  Australians  as  a  rule  are  credited 
with  being  fairly  well  versed  in  the  possibilities 
of  gold  mining,  and  had  anything  like  6-oz. 
ore  been  forthcoming  on  a  decent  scale  in  any 
of  the  Northern  Territory  mines  the  boom  that 
would  be  created  would  astonish  everyone. 
As  it  is  everything  in  the  Northern  Territory 
is  as  dull  as  ditchwater. 

TORONTO. 

Porcupine. — The  approach  of  winter  has 
been  accompanied  by  great  activity  in  trans- 
porting mining  and  mill  machinery.     A  large 
amount   of   building   has   been  accomplished 
during  the  last  few  weeks,  operations  having 
been  rushed  with  all  possible  speed  so  as  to 
get   everything   in    shape   before    the    severe 
weather  sets  in.     The  principal  interest  now 
centres  in  the  completion  of  the  mills  in  con- 
nection with  the  leading  mines,  especially  the 
Dome,   Hollinger,  and  Vipond,  all  of  which 
are  expected  to  be  in  readiness  to  begin  op- 
erations early  next  year.     The  Dome  is  likely 
to  be  the  first  in  the  field  some  time  in  Feb- 
ruary.    For  about  a  month  the  crushing  op- 
erations will  be  confined  to  low-grade  ore  in 
order  to  get  the  stamps  in  good  working  order. 
The  Hollinger  hopes  to  get  to  work  in  March, 
while  the  Vipond  management  state  that  Feb- 
ruary will  see  their  mill  in  operation.     Its 
construction  is  of  a   simpler  character  than 
that  of  its  rivals,  having  tube  and  pebble  mills 
in  place  of  stamps.     The  ore  will  be  crushed 
to  200-mesh  before  amalgamation  and  owing 
to  the  free-milling  character  of  the  ore  the 
cyanide  process  will  not  be  required  until  the 
tailing  has  accumulated.     The   Mclntyre  10- 
stamp  mill  will  be  installed  during  the  winter. 
During  the  last  week  of  October  a  number 
of  the  directors  and  stockholders  of  the  Dome, 
including  several  prominent  American  finan- 
ciers, visited  the  property.     Ambrose  Monell, 
the  managing  director,  states  that  diamond- 
drill  work  over  an  area  of  1000  ft.  had  greatly 
improved  the  prospects  of  the  property,  prov- 
ing an  enormous  body  of  milling  ore  in  depth, 
though  it  was  too  early  to  speak  positively  as 
to  its  assay-value,  excepting  as  regards  the 
surface  and  the  50-ft.  level.      Of  two  drifts 
run  at  that  level,  one  showed  ;$28  ore  for  136 
ft.,  while   the  gold   contents  exposed  by  the 
other,  running  parallel,  ran  from  $30  to  $40 
per    ton.      Two    additional  shafts  are  going 
down.     At    the    Dome    Extension   the   main 
shaft  has  reached  180  ft.     Cross-cutting  will 
be  done  at  200  ft.  to  cut  several  northerly 
veins.     On  the  West  Dome  three  shafts  are 
going  down  and  some  cross-cutting  has  been 


430 


THE    MINING    MAGAZINE 


done  at  the  125-ft.  level.  A  mill  will  be 
built  in  the  spring.  Underground  work  is 
being  actively  pushed  at  the  Hollinger.  Con- 
nections are  being  made  at  the  200-ft.  level 
with  the  shaft,  which  will  be  put  down  to  400 
ft.,  the  main  working  level.  At  the  Miller- 
Middleton  adjoining,  operated  by  the  Tim- 
mins-McMartm  syndicate,  a  shaft  is  down 
50  ft.  and  a  cross-cut  is  being  run  into  the 
hillside  to  connect  with  it.  The  Crown  Char- 
tered, in  drifting  on  the  100-ft.  level,  has  got 
into  pay-ore  in  a  schist  and  quartz  vein  at 
least  50  ft.  wide.  Some  high-grade  ore  has 
been  encountered.  The  vein  of  the  Davidson 
property  operated  by  this  company  has  been 
cut  at  depth  and  shows  good  milling  ore.  The 
main  shaft  of  the  Eldorado  is  down  28  ft.  and 
has  encountered  numerous  quartz  stringers. 
The  Dobie  is  getting  in  additional  mining 
equipment.  No.  2  shaft  is  being  deepened 
to  reach  a  promising  orebody  discovered  by 
diamond-drilling.  Bert  Furrier  has  been  ap- 
pointed manager  of  the  Rea  mine.  No.  1 
shaft  has  reached  the  300-ft.  level  and  cross- 
cutting  at  that  level  shows  the  vein  to  be 
equally  strong  as  at  200  ft.  The  Porcupine 
Reserve  is  sinking  on  a  quartz  and  schist 
lode  75  ft.  wide  carrying  some  gold. 

Cobalt. — Though  the  production  of  silver 
by  the  Cobalt  mines,  and  the  payment  of 
dividends  by  the  leading  producers  are  well 
maintained,  there  is  comparatively  little  in- 
terest now  taken  by  the  public  in  this  district, 
and  the  stock  market  has  been  very  dull  for 
some  time,  many  of  the  cheaper  issues  having 
disappeared  from  the  list.  La  Rose  has 
lately  improved  its  position  by  some  good 
discoveries,  including  an  ore-shoot  on  the 
Lawson  property  6  in.  wide  averaging  5000 
oz.  per  ton,  and  other  finds  on  the  Princess 
and  Fisher- Eplett.  A  statement  covering  the 
first  nine  months  of  the  year  shows  a  total 
production  of  2,751,946  oz.,  having  a  gross 
value  of  §1,444,271,  and  shipments  aggregat- 
ing 3,179,985  oz.  The  income  was  $1,453,958, 
the  expenses  $536,868,  leaving  an  operating 
profit  of  $916,765,  being  an  average  of 
approximately  $102,000  per  month.  The 
Nipissing  has  recently  considerably  increased 
its  ore  reserves.  The  high-grade  ore  is  now 
treated  by  the  Butters  plant  and  it  is  claimed 
that  with  a  few  alterations  in  the  process 
low-grade  ores  can  be  treated  successfully, 
and  that  from  several  thousand  tons  of  low- 
grade  ore  accumulated  a  recovery  of  93%  or 
better  could  be  secured  at  a  cost  of  $3  per 
ton.  In  the  spring  extensive  hydraulic  opera- 
tions will  be  undertaken  for  the  removal  of 


the  overburden  on  the  property  in  the  hope  of 
discovering  new  veins.  The  hydraulic  pump 
installed  for  the  purpose  has  been  successfully 
tested.  It  throws  a  stream  of  4800  gallons 
of  water  per  minute  and  has  a  head  of  415  ft. 
The  Crown  Reserve  has  opened  up  several 
new  ore-shoots.  On  the  170-ft.  level  the  vein, 
which  was  lean,  suddenly  widened  to  4  in.  of 
ore  stated  to  run  6000  oz.  per  ton.  Cobalt 
Lake  has  picked  up  a  cobalt  vein  100  ft.  from 
the  shaft  on  the  100-ft.  level  which  carries 
200  oz.  silver  and  is  taking  out  much  ore. 
The  mill  is  running  steadily  treating  about 
75  tons  per  day.  The  Temiskaming  has 
passed  its  quarterly  dividend  in  order  to 
devote  the  money  to  the  purchase  of  a  con- 
trolling interest  in  the  North  Dome  at  Porcu- 
pine. 

NEW  YORK. 

Stock  quotations,  especially  on  mining 
shares,  are  buoyant  in  spite  of  the  prevailing 
uncertainty  as  to  future  political  events.  They 
reflect  an  underlying  activity  in  nearly  all  in- 
dustrial lines.  The  market  for  copper  and 
steel  is  good,  being  supported  more  and  more 
strongly  by  the  purchases  of  smaller  con- 
sumers. The  entire  list  of  mining  shares 
traded  on  the  New  York  Stock  Exchange  has 
recorded  decided  gains  within  the  past  month  ; 
for  example.  Amalgamated,  lOi;  A.  S.  &  R., 
lOi  ;  Chino  and  Miami  each,  3f ;  National 
Lead,  7*  ;  Tennessee  Copper,  4;  and  Utah 
Copper,  7*.  The  behaviour  of  the  United 
States  Steel  stocks  has  been  still  more  strik- 
ing :  during  the  period  of  uncertainty,  common 
fluctuated  around  55  and  preferred  around 
105  :  in  the  excitement  following  the  Govern- 
ment's suit,  common  dropped  to  50  and  pre- 
ferred to  103  ;  but  now  that  the  issues  are 
clearly  drawn,  the  market  evidently  has  con- 
fidence in  the  final  outcome,  for  common  has 
climbed  to  64  and  preferred  to  109.  To  be 
sued  by  the  Government  seems  to  be  good 
advertising. 

Mineral  land  laws,  which  for  40  years 
have  been  the  source  of  constant  irritation 
and  litigation,  may  be  revised  in  the  not  dis- 
tant future.  The  American  Mining  Congress, 
among  the  several  societies  whose  members 
are  interested  in  the  business  of  mining,  has 
taken  the  lead  in  subjecting  the  present  laws 
to  constructive  criticism  and  in  agitating  for 
reform.  The  present  plan  of  this  organization 
is  to  appoint  a  committee  to  confer  with  a 
commission  from  the  House  of  Representa- 
tives, and  with  the  assistance  of  an  advisory 
board  of   engineers   and   mining   experts,    to 


DECEMBER,    1911 


431 


evolve  a  new  code  in  the  light  of  modern 
knowledge  of  the  occurrence  of  ore  deposits. 
It  was  the  lack  of  this  knowledge  that  was 
principally  responsible  for  the  passing  of  the 
law  of  1872,  which  has  since  proved  to  be  in- 
consistent and  impracticable  in  many  cases. 
It  is  an  almost  foregone  conclusion  that  an 
essential  feature  of  the  new  law  will  be  the 
adoption  of  vertical  planes  as  boundaries  on 
all  sides  of  a  mining  property,  thus  avoiding 
the  confusion  that  arises  from  the  present  al- 
lowance of  extra-lateral  rights.  Another  com- 
mendable feature  will  probably  be  the  intro- 
duction of  a  stipulation  that  will  make  it  more 
difficult  for  a  company  to  pre-empt  a  large 
number  of  claims  and  hold  them  indefinitely 
by  the  performance  of  a  merely  nominal 
amount  of  annual  assessment  work,  without 
making  an  effort  to  develop  them  into  mines. 
In  already  occupied  mining  districts,  of  course, 
a  large  amount  of  adjusting  will  be  necessary 
to  reconcile  the  old  arrangement  with  the 
new.  The  Mining  Congress  has  the  support 
of  the  Governors  of  many  Western  states  and 
of  many  members  of  the  national  legislature, 
whence  the  probability  of  carrying  through  the 
proposed  revision  is  brighter  than  it  ever  has 
been.  Your  British  readers  may  not  under- 
stand that  the  national  mining  law  relates  only 
to  the  formalities  necessary  to  be  followed  in 
obtaining  possession  of  a  piece  of  mining 
ground  situated  in  the  public  domain.  It  has 
no  jurisdiction  whatever  over  the  method  of 
operating  a  mine  ;  under  the  Constitution,  all 
matters  relating  to  the  health  or  safety  of  in- 
dividuals are  delegated  to  the  governments  of 
the  several  States.  A  federal  law  analogous 
to  the  British  Mines  Regulation  Act  would 
therefore  be  uninforceable  in  this  country. 
It  is  fair  to  say  that  most  of  the  States  in 
which  mining  is  conducted  have  realized  their 
responsibility  in  this  direction. 

The  Bureau  of  Mines  is  likely  to  be 
burdened  with  a  wider  field  of  endeavour,  at 
the  instigation  of  members  of  Congress  with 
Western  constituencies.  The  chairman  of  the 
congressional  committee  on  mines  and  mining 
has  been  in  consultation  with  the  Director  of 
the  Bureau  in  the  drafting  of  a  revised  statute 
to  be  submitted  at  the  forthcoming  session, 
and  certain  societies  of  mining  engineers  have 
been  invited  to  offer  advice.  The  alteration 
most  prominently  suggested  is  the  insertion 
of  a  provision  to  allow  the  Bureau  to  under- 
take the  investigation  of  processes  in  ore- 
dressing  and  metallurgy  ;  the  nominal  object 
of  conserving  national  resources  is  to  be  at- 
tained   by   diminishing    losses    in    treatment. 


The  exploration  of  mineral  lands  by  boring, 
the  abatement  of  smoke  nuisance  at  smelters, 
and  the  development  of  more  economical  and 
efficient  methods  of  mining  are  also  mentioned 
as  proper  fields  for  the  Bureau's  activities. 
In  regard  to  work  of  this  character  it  may 
be  said  that  if  the  big  operating  companies, 
with  self-interest  to  prompt  them,  with  the 
most  eminent  engineers  to  advise  them,  and, 
in  many  cases,  with  ample  funds  to  devote  to 
such  purposes,  are  not  able  to  solve  these 
problems  in  economy,  it  is  exceedingly  doubt- 
ful whether  the  Bureau  of  Mines  will  be  any 
more  successful.  The  most  valuable  work 
now  being  done  by  the  Bureau  is  its  investi- 
gations into  the  prevention  of  coal-mine  ex- 
plosions, which  it  inherited  from  the  Techno- 
logic branch  of  the  Geological  Survey.  It 
has  established  thoroughly  equipped  rescue 
stations  at  a  number  of  points  throughout  the 
coalfields,  and  also  maintains  a  number  of 
cars  that  can  be  sent  by  rail  at  short  notice 
to  any  mine  in  need  of  expert  services  and 
life-saving  equipment.  It  has  also  under- 
taken to  train  the  more  intelligent  among  the 
coal-mine  workers  in  the  arts  of  combating 
explosions,  subduing  mine  fires,  and  rescuing 
and  resuscitating  injured  miners.  Even  these 
commendable  and  humanitarian  endeavours 
should  be  looked  upon  rather  as  the  setting 
of  a  good  example  to  coal  operators  than  the 
relieving  of  the  states  from  their  direct  re- 
sponsibility for  such  activities. 

Southwestern  copper  mines  continue 
to  develop.  Miami  is  now  operating  five  of 
the  six  sections  of  its  mill,  and  produced 
2,000,000  lb.  copper  during  November ;  this 
will  soon  be  increased  to  3,000,000  lb.  per 
month.  The  cost  is  8"5  cents  per  pound,  de- 
livered at  New  York.  The  company  is  now 
managing  its  own  sales,  at  prices  averaging 
13'25  c.  per  pound.  Negotiations  for  the 
sale  of  the  Live  Oak  mine  to  the  Miami  com- 
pany were  about  to  be  successfully  concluded 
when  they  were  abandoned  on  objections  from 
the  Live  Oak  directors.  These  then  opened 
another  trade  with  John  D.  Ryan,  who 
promptly  purchased  control  and  a  large 
amount  of  minority  stock,  at  $30,  or  about 
the  market  quotation.  It  is  rumoured  that 
this  is  only  a  forerunner  of  a  wider  consolida- 
tion under  the  Cole-Ryan  auspices,  into  which 
Miami  and  Inspiration  may  be  drawn.  Miami 
has  regularly  been  shipping  its  concentrate 
to  the  Cole- Ryan  smelter  at  Cananea,  Mexico, 
which,  on  its  face,  would  appear  to  be  a  less 
convenient  arrangement  than  to  smelt  at 
Douglas,  Arizona. 


432 


THE    MINING    MAGAZINE 


METAL  MARKETS 

COPPER. 

Average  prices  of  cash  standard  copper : 

Nov.  1911.  Oct.  1911.         Nov.  1910. 

£bl.  8s.  3d.       £Sb.  5s.  2d.      £bl .  15s.  3d. 

The  rapidity  with  which  the  world's  stocks 
are  being  drawn  upon  has  at  last  arrested  the 
attention  of  the  speculative  public.  The  con- 
tinued decrease  in  stocks  both  in  Europe  and 
America  is  evidence  of  enormous  activity  and 
prosperity.  This  activity  has  hitherto  been 
confined  to  Europe,  but  the  American  rail- 
ways have  recently  placed  large  equipment 
orders  and  improved  conditions  are  reported 
from  that  side.  For  October  this  consumption 
showed  an  improvement  of  3000  tons,  and  the 
November  figures  show  an  increase  in  domestic 
consumption  of  2000  tons  and  in  export  of  3500 
tons.  Should  American  trade  continue  to 
follow  the  European  lead,  the  pessimistic 
views  hitherto  held  in  many  quarters  as  to  the 
baleful  effect  on  prices  of  the  increased  output 
from  the  new  '  porphyry '  mines  will  be  re- 
vised. Orders  held  back  during  the  recent 
political  disturbance  have  recently  been  placed 
and  the  demand  has  been  so  active  that  the 
leading  producers  are  practically  sold  ahead 
for  two  months.  They  have  continuously 
raised  prices  to  13*  c.  for  electrolytic.  On  the 
Metal  Exchange  prices  rose  from  £bb.  15s. 
to  ;^60  for  3  months,  accompanied  by  a  rapid 
advance  in  copper  shares.  The  excitement 
was  reminiscent  of  the  1907  boom.  Every 
rise  in  price  has  stimulated  fresh  demand  and, 
as  early  delivery  is  insisted  on,  it  may  be  pre- 
sumed that  stocks  in  the  works  are  low. 

TIN. 

Average  prices  of  cash  Straits  tin  : 
Nov.  1911.        Oct.  1911.         Nov.  1910. 
£\9\.  19s.  4d.    /187.  2s.  9d.    ;^166.  IBs.  Od. 

Tin  shows  a  steady  advance  in  price  during 
the  month  of  about  £\S,  and  a  widening  of  the 
backwardation  which  now  amounts  to  ^1 1  per 
ton.  Dealings  under  the  new  contract  were 
introduced  on  November  1  and  the  syndicate 
brokers  who  are  hostile  to  it  have  been  buying 
up  the  available  supply  of  Straits  tin,  so  that 
the  market  has  degenerated  into  a  record  of 
their  doings.  Otherwise  speculation  has  been 
greatly  reduced  by  the  high  prices  and  distrust 
of  the  syndicate.  A  good  consumptive  demand 
however  set  in  about  the  middle  of  the  month 
and  assisted  the  bull  operators  in  Straits  tin, 
A  large  business  was  transacted  from  day  to 
day  in  the   East,   but   the   market  otherwise 


has  become  entirely  professional  and  artificial 
especially  for  prompts  short  of  February  1. 
The  Banka  sale  realized  an  average  of  ;^208. 
This  has  brought  out  buyers  for  December 
prompts  who  bid  up  the  price  to  /^205,  most 
of  the  supplies  coming  from  the  syndicate 
brokers,  who  thus  gave  the  market  a  welcome 
relief.  Standard  tin  was  also  in  better  demand 
and  the  price  was  raised  to  ^192.  10s.  The 
November  statistics  show  an  increase  of  2643 
tons,  just  about  equal  to  the  Banka  taken  into 
stock  on  the  30th. 

LEAD. 

Prices  of  soft  foreign  lead  : 

Nov.  1911.  Oct.  1911.         Nov.  1910. 

^15.  15s.  5d.      ^15.  6s.  Id.      ;^13.  4s.  6d. 

Lead  has  shown  a  further  advance  and  at 
one  time  ;^16  was  freely  paid  for  spot.  Con- 
sumption has  shown  enormous  expansion,  for 
which  the  falling  off  in  production  has  not  pre- 
pared the  dealers.  The  strike  of  Australian 
wharf  labourers,  further  unrest  in  Mexico,  and 
the  heavy  advance  in  freight  rates  give  rise  to 
a  belief  in  the  continuance  of  the  scarcity. 
Nevertheless  demand  seems  to  have  quietened 
down  and  lower  prices  will  probably  be  seen  in 
December,  when  trade  usually  falls  off.  Prices 
are  already  somewhat  easier  at  £\b.  17s.  6d. 

SPELTER. 

Average  prices  of  spelter  : 
Nov.  1911.  Oct.  1911.  Nov.  1910. 

^26.  13s.  2d.  ;^27.  4s.  lOd.  ^24.  Is.  9d. 
Prices  show  little  variation.  The  conven- 
tion, after  the  substantial  cut  last  month,  has 
again  advanced  prices  by  5s.  Better  reports 
are  received  from  the  galvanized  iron  and  zinc- 
sheet  trades.  By  insisting  on  buyers  purchas- 
ing on  average,  the  convention  is  arousing  some 
dissatisfaction. 

OTHER  METALS  AND  MINERALS. 

Prices  quoted  on  December  9  : 

Silver. — 25fd.  per  oz. 

Platinum. — 185s.  per  oz. 

Bismuth. — 7s.  6d.  per  lb. 

Aluminium. — ;^53  per  ton. 

Nickel. — £11^  per  ton. 

Cobalt. — 9s.  9d.  per  lb. 

Antimony. — ;^28  per  ton. 
■Quicksilver. — ;^8.  2s.  6d.  per  flask. 

Manganese  Ore. — 8d.to9*d.  per  unit  (1%). 

Iron  Ore. — Cumberland  hematite  19s.  6d. 
per  ton  at  mine.    Spanish  20s.  delivered. 

Pig  Iron. — Cleveland47s.  9d.perton.  He- 
matite 61s.  per  ton. 

Wolfram  Ore — 30s.  per  unit  (1%). 


DECEMBER,    1911 


433 


DISCUSSION 

Our  readers  are  invited  to  criticize  anything  appearing  in  this 
magazine  and  to  discuss  other  subjects  of  general  technical 
interest. 

Sampling. 

The  Editor: 

Sir — There  seems  to  be  little  written  in  re- 
gard to  the  quantity  of  samples  that  can  or- 
dinarily be  crushed  per  day,  preparatory  to 
'bucking  down,'  in  view  of  which  the  following 
data  may  be  of  interest.  Perhaps  they  are 
peculiar  to  practice  in  Chile. 

The  samples  were  reduced  to  about  4  inch 
mesh  and  quartered  to  a  weight  of  2  kilo,  pre- 


Reduihiii   Snmplex. 

vious  to  fine  crushing  as  shown  in  the  photo- 
graph. The  circular  plate,  4  ft.  diam.,  is  a 
casting  with  a  rim  3  in.  high,  the  outlet  or 
discharge'  being  6  inches  wide.  The  'muUer' 
weighs  from  100  to  125  lb.  (as  shown  it  is  15 
in.  diam.  and  12  in.  high),  the  heavier  weight 
giving  better  results,  and  can  be  manipulated, 
with  practice,  without  much  force  being  re- 
quired ;  a  circular  or  gyratory  motion  is  given 
to  the  handle,  so  that  the  '  muller  '  moves  over 
the  spread-out  sample  rapidly,  and  crushes 
without  causing  the  pulp  to  fly  off  the  plate. 
A  practised  hand  can  readily  crush  a  sample, 
as  mentioned  above,  so  that  60%  of  it  is  finer 
than  20  mesh  in  4  to  5  minutes.  It  should 
be  stated  that  the  material  crushed  was  a  cop- 
per-bearing (chiefly  chrysocollaand  malachite) 
andesite. 

With  the  four  men  shown — the  two  in  the 
foreground  doing  the  crushing  alternately,  the 


third  clearing  up  the  crushed  sample  into  the 
sample-ba?,  while  the  fourth  assisted  in  mix- 
ing the  sample  prior  to  it  being  quartered  on 
the  sampler — it  was  possible  to  crush,  quarter, 
mark,  sack  in  duplicate,  and  seal  150  samples 
(averaging  about  150  gm.  each)  in  12  working 
hours — from  7  a.m.  to  10  p.m. — allowing  3 
hours  for  meals  and  rest. 

The  photograph  shows  the  arrangement 
used  to  supervise  the  work  while  the  quarter- 
ing was  being  done.  Incidentally  it  might  be 
added  that  the  labour  cost  (at  25  centavos  per 
hour — or  5"6  cents  U.S.  currency)  was  12 
pesos  (about  $270)  or  8  centavos  (about  \'H 
cents)  per  sample. 

L.  W.  Strauss. 

Chala,  Chile,  October  13. 

Cyanidation  v.  Concentration. 

The  Editor : 

Sir — Opinion  is  divided  in  Mexico  on  the 
subject  of  concentration  as  applied  to  ordinary 
milling  ores,  such  as  those  of  Pachuca.  Dis- 
cussion, however,  generally  proceeds  upon 
metallurgical  lines  and  the  crux  of  the  argu- 
ment lies  in  the  comparative  efficiency  of  the 
method  of  direct  cyanidation,  as  compared 
with  a  combination  of  concentration  and 
cyanidation. 

The  object  of  this  note  is  to  point  out  that 
the  comparative  result  reaches  beyond  the 
mere  metallurgical  efficiency  and  should  be 
based  upon  the  cost  per  ounce  of  silver  pro- 
duced, particularly  because  of  the  high  refin- 
ing charge  on  the  silver  bullion  sold  from  the 
cyanide  plant. 

It  is,  of  course,  generally  known  that  the 
silver  bullion  produced  from  a  cyanide  plant 
is  more  or  less  base,  and  must  be  refined  be- 
fore it  can  be  marketed,  but  it  is  not  gener- 
ally known  that  the  refining  charges  equal 
about  0'8d.  per  ounce  of  bullion  which  adds 
appreciably  to  the  cost  per  ounce  of  fine  silver 
produced.  To  take  a  case  :  An  ore  that  yields 
30  oz.  fine  silver  per  ton  returns  33*30  oz.  of 
900  fine  bullion.  At  a  cost  of  0"8d.  per  oz.  of 
bullion  the  refining  charge  per  ounce  of  fine 
silver  produced  comes  to  approximately  0'89d. 
The  yield  per  ton  in  fine  silver  being  30  oz., 
the  refining  charge  adds  no  less  than  26*7d. 
per  ton  to  the  cost  of  production. 

On  normal  Pachuca  ores  it  is  usual  to  get, 
in  a  concentrate  representing  half  of  one  per 
cent,  of  the  ore  milled,  about  20%  of  the  total 
assay-value,  that  is,  a  ton  of  ore  assaying  30 
oz.  per  ton — assuming  for  this  purpose  com- 
plete extraction — will  yield  101b.  of  concen- 
trate assaying  1200  oz.  per  ton.     The  cost  to 


434 


THE    MINING    MAGAZINE 


produce  a  ton  of  concentrate  in  Pachuca  is 
just  about  £\0  per  ton,  the  freight  and  treat- 
ment charges  are  about  42s.  per  ton  and  the 
deduction  for  loss  in  silver  treatment  is  5%. 
Therefore  the  cost  per  ounce  of  silver  pro- 
duced from  concentrate  is  as  under  : 

Cost  to  preduce  1  ton  of  concentrate ;flO     0     0 

Freight  and  treatment 2     2     0 

Loss  in  treatment 6     0     0 

/18     2     0 
Total  silver  produced  from  one  ton  of  con- 
centrate     IHO  oz. 

Cost  to  produce  one  ounce  of  silver 3  83d. 

There  are  no  refining  charges  made  on  con- 
centrate, therefore  the  above  figure  represents 
the  final  cost. 

The  approximate  total  cost  for  producing 
an  ounce  of  fine  silver  by  cyanide  treatment 
from  a  20  oz.  ore  is  as  under : 

Per  ton 
Cost  of  cyaniding,  precipitation,  and  melting..  4s.  6d. 

Refining  cost 2s   3d . 

Loss  on  treatment 5s.  6d. 

12s.  3d. 
Total  fine  silver  produced  from  one  ton  of  ore...  27  oz. 
Cost  per  ounce  of  fine  silver  produced 5'44d. 

No  commissions  are  charged  in  eitlier  case 
on  the  bullion  realizations,  but  these  would 
favour  the  case  for  part  concentration. 

The  example  cited  must  be  taken  to  refer 
of  course  only  to  Pachuca  conditions.  Every 
case  must  naturally  be  settled  in  accordance 
with  the  particular  circumstances  presented. 
Variations  in  grade  of  ore,  in  cost  of  cyanida- 
tion,  in  freight  and  smelter  rates,  and  possi- 
bilities for  concentrating  valuable  contents 
into  small  bulk,  materially  affect  the  question, 
so  that  no  general  rule  applies  all  round. 

Account  must  also  be  taken  of  the  fact  that 
from  the  smelter  it  is  rare  to  get  a  satisfactory 
reconciliation,  either  on  the  dry  weight  of  the 
concentrate,  or  on  its  assay-value. 

G.  A.  Denny. 

London,  November  15. 

Standardization  in  Assays. 

The  Editor  : 

Sir — In  these  days  the  tendency  is  to  stan- 
dardize methods  and  materials,  for  reasons 
that  are  self-evident.  In  mining  and  metal- 
lurgy the  powers  that  be  have  striven  to  stan- 
dardize as  far  as  possible.  It  would  appear 
unnecessary  to  standardize  in  the  method  of 
reporting '  moisture  '  present  in  ores,  etc. :  that 
moisture  could  be  reported  otherwise  than  in 
percentage  seems  almost  impossible,  yet  at 
least  one  large  metallurgical  works  in  Great 
Britain  reports  moisture  in  terms  of  drachms 
of  water  in  one  pound  of  material.     Another 


equally  large  and  influential  firm  reports  mois- 
ture in  a  way  that  is  equally  puzzling  to  an 
engineer,  thus  :  if  a  material  contain  10%  of 
moisture   the    report    will    read :    "  Moisture 

meaning  presumably  700  (grains)  of 

7000," 

moisture  in  7000  (grains,  or  one  lb.  avoir- 
dupois) of  material.  It  is  only  reasonable  to 
assume  that  both  the  above  mentioned  me- 
thods of  reporting  '  moisture  '  must  in  some 
respects  be  superior  to  the  percentage  method, 
which  the  writer  had  previously  thought  was 
almost,  if  not  quite,  universal,  or  else  the 
methods  must  be  a  relic  of  a  by-gone  age. 
These  two  instances  may  perhaps  be  of  assist- 
ance to  some  who,  after  working  for  years 
with  modern  methods  in  the  back  and  be- 
yond, are  suddenly  confronted  with  other 
ways  of  doing  the  same  thing. 

From  trie  above  it  will  be  seen  how  neces- 
sary it  is  to  standardize  even  the  methods  of 
reporting  the  amount  of  moisture  present  in 
ores,  etc.,  and  equally  how  little  effect  the  at- 
tempt to  introduce  the  metric  system,  even 
where  most  easily  adopted,  has  in  some  quar- 
ters. 

The  successful  standardization  of  weights 
used  by  gold  and  silver  assayers  would  guard 
against  errors  frequently  made,  some  of  which 
involve  enormous  losses. 

It  is,  in  the  colonies  at  least,  usual  for  as- 
sayers on  gold  mines  to  use  for  weighing  their 
parted  gold  a  set  of  weights  in  which  1000=  1 
gramme  and  therefore  the  weight  marked  1  =  1 
milligramme  ;  this  appears  good  practice  and 
serves  as  a  direct  link  with  the  well  known 
assay-ton  weight.  There  is  also  a  set  of 
weights  made  in  which  1000  =  i  gramme, 
and  therefore  the  weight  marked  1=^  milli- 
gramme. It  may  be  urged  that  the  weights 
of  these  two  separate  sets  would  even  if 
'  mixed  '  be  detected  at  once  on  sight ;  it  may, 
or  may  not,  be  so,  but  the  fact  remains  that 
serious  errors  have  sometimes  come  about 
through  mixing  these  two  classes  of  weights, 
causing  assay  results  to  be  reported  at  either 
double  or  half  the  truth.  In  a  notorious  case 
a  few  years  ago  the  whole  of  the  assays  for 
one  level  of  a  developing  mine  were  reported 
and  mapped  at  double  their  true  value,  and 
when  the  error  was  discovered  it  proved  seri- 
ous for  the  assayer,  and  also  someone  else. 

It  must  be  remembered  that  assayers  on 
gold  mines  usually  work  at  high  pressure,  and 
unlike  some  of  their  city  colleagues  have  to 
turn  out  results  promptly  if  they  are  to  be 
of  any  use  to  the  management,  and  nothing 
but  loss  of  time  and  risk  of  error  can  result 


DECEMBER,    1911 


435 


from  using  more  than  one  system  of  weights 
on  the  same  balance.  With  the  extremely 
sensitive  assay -balances  now  used  on  gold 
mines  it  is  doubtful  if  any  weight  or  rider 
weighing  less  that  1  milligramme  can  possibly 
be  required. 

A  strange  weight  used  is  an  assay  -  ton 
'grain'  weight;  it  is  stated  to  be  necessary 
for  those  who  still  report  results  only  in  grains 
per  ton.  When  this  assay- ton  '  grain  '  weight 
was  used  in  error  instead  of  the  standard  short 
assay  -  ton  weight  for  weighing  the  assay 
charge,  and  the  parted  gold  was  weighed  in 
terms  of  milligrammes,  the  result  can  be 
imagined. 

H.    T.    DURANT. 

London,  November  15. 

A  Miner's  Protest. 

The  Editor  : 

Sir — In  your  current  issue,  '  Reef  Miner' 
protests  against  the  assertions  (authorities  not 
quoted)  as  to  the  inefficiency  of  Rand  miners. 
In  raising  his  protest,  he  wields  the  bludgeon 
of  his  angry  resentment  fiercely  and  blindly, 
and  it  is  difficult  to  determine  his  final  aim. 
In  getting  at  his  unspecified  victim,  however, 
your  correspondent  does  so  much  miscellane- 
ous damage  on  the  way,  that  I  will  merely 
examine  this  subsidiary  wreckage,  leaving  the 
poor  battered  culprit  to  appear  from  beneath 
and  reply  for  himself. 

Concerning  the  general  proposition  as  to 
whether  the  Rand  miner  is  '  inefficient  '  or 
otherwise,  it  seems  to  me  just  as  futile  to  at- 
tempt to  demonstrate  the  average  efificiency 
of  an  essentially  heterogeneous  body  of  15,000, 
as  to  prove  their  '  inefficiency.'  The  terms, 
implying  our  ability  to  estimate  an  average, 
are  purely  relative  to  their  application,  and 
there  exists  no  outside  standard  for  compari- 
son. It  is  a  matter  of  personal  opinion,  based 
largely  on  impressions  that  must  vary  with 
different  experiences.  There  are  many  authori- 
ties who  have  good  right  to  express  their  views, 
but  debate  of  so  indefinite  a  question  affords 
no  satisfactory  means  of  proof,  suggests  no 
scheme  for  improvement,  and  creates  much 
bitterness  of  feeling.  A  comparison  of  the 
Rand's  average  efficiency  of  today,  and  of, 
say,  five  years  ago,  might  be  attempted  on  a 
rational  basis  of  detailed  mining  results.  But 
even  then,  we  would  have  no  right  to  inter- 
pret better  or  worse  average  results  as  clear 
evidence  of  greater  or  less  individual  efficiency 
or  output  of  work.  There  are  too  many  vari- 
able factors,  such  as  quality  and  working  condi- 
tionsthatwouldstill  leave  the  question  obscure. 


'  Reef  Miner  '  writes  in  an  angry  mood,  and 
seems  anxious  to  aggravate  bad  feeling  be- 
tween masters  and  men,  like  some  of  the  good 
people  who  fatten  on  that  turbid  sentiment. 
Pardon  me,  therefore,  if  I  endeavour  to  carry 
the  discussion  to  a  lighter  atmosphere.  We 
read :  "  In  other  trades,  the  best  market  at- 
tracts the  most  skilled  men.  I  believe  we 
have  the  best  miners  from  Europe,  America, 
and  the  Colonies.  It  is  the  system  for  which 
the  managers  are  responsible  that  is  bad."  It 
seems  strange  indeed  that  the  "  best  market  " 
should  attract  the  "  most  skilled  men"  among 
miners  but  not  among  managers.  Perhaps 
'  Reef  Miner '  places  management  under  the 
head  of  white  unskilled  labour,  for  which  the 
Rand  is  admittedly  unattractive.  He  proceeds 
at  great  length  to  discuss  the  useful  influence 
upon  the  Kaffir  of  the  Rand  miner  who  "con- 
verts the  useless  latent  power  of  the  native 
into  a  useful  profitable  asset.  It  is  a  psycho- 
logical peculiarity  of  the  native  that  his  ideas 
of  direction  and  motion  are  round.  It  may 
be  environment."  I  don't  think  a  lode  or  coal 
miner  would  agree  with  '  Reef  Miner  '  here  ; 
not  verbatim.  He  would  be  more  likely  to 
attribute  the  predilection  to  constitutional  an- 
tipathy to  pedal  parabolae.  Continuing,  he 
says:  "  His  first  idea  was  circular  ....  all 
his  fortifications  are  circular,  his  utensils,  his 
hut,  threshing-floors,  wicker  cages,  baskets, 
pottery,  and  cooking  gear  are  round."  Why 
on  earth  should  this  mental  bias  be  recorded 
as  proof  of  the  Kaffir's  latent  uselessness  in 
mining  ?  Some  of  the  best  Rand  miners  of 
my  acquaintance  are  feverishly  anxious  to  see 
a  good  round  figure  on  their  monthly  cheques 
and  then  to  obtain  the  value  of  these  rectan- 
gular slips,  without  delay,  in  circular  form. 

Although  so  unconvincing,  '  Reef  Miner' 
follows  this  washy  line  of  argument  still  fur- 
ther. He  even  tells  us  how  he  "  put  in  four 
pegs  for  a  rectangular  prospecting  pit  in  Rho- 
desia and  started  a  native  accordingly."  He 
"  came  back  in  three  days.  It  was  a  circular 
shaft.  The  savage  reverted  to  type.  There- 
fore the  native  cannot  be  a  miner."  Truly  a 
startling  and  illogical  inference  ;  and  what  poor 
appreciation  of  the  trusty  native  miner,  who 
only  wished  his  absent  manager  to  keep  abreast 
of  the  times  in  shaft-sinking  practice. 

'  Reef  Miner'  also  wields  two  blows  at  the 
Transvaal  mining  regulations  and  deplores 
their  excessive  severity  upon  miners  and  the 
crushing  penalties  for  their  abuse.  That  these 
regulations  are  exceptionally  elaborate  in  their 
injunctions  on  all  classes  of  white  employee 
(official  and  otherwise),  owing  to  the  peculiar 


6—4 


436 


THE    MINING    MAGAZINE 


element  of  responsibility  attaching  to  the  con- 
trol of  raw  natives,  is  to  be  readily  admitted, 
but  it  must  also  be  understood  that  they  are 
applied  with  proper  latitude,  discriminating 
between  the  culpable  carelessness  of  the  old 
offender  and  the  faults  of  the  comparatively 
inexperienced,  but  well  meaning,  young  miner. 
If  the  regulations  were  invariably  acted  upon 
by  quibbling  lawyers,  instead  of  by  men  with 
a  common-sense  appreciation  of  mining  diffi- 
culties, they  might — like  the  Home  regula- 
tions, passed  and  contemplated — become  the 
curse  '  Reef  Miner'  suggests. 

Finally  your  correspondent  strikes  off  tan- 
gentially  from  the  Kaffir  circles,  and  indicates 
that  nowadays  it  is  typical  to  drive  the  wrong 
way  upon  cutting  a  fault  in   Rand  develop- 
ment.    He  adds:    "Compare  the  drifts  ad- 
vanced in  pre-war  days,  when  the  miner  was 
paid  and  appreciated,  with  the  modern  man- 
ager's workings.      Something  needs  blotting 
out :  better  it  would  be  to  totally  blot  out  the 
present  methods."     This  final  sweep  of  the 
bludgeon  is  simply  devastating.      It  indicates, 
too,  a  healthy  spirit  of  constructive  reform. 
The  question  is  again  one  calling  for  more 
judgment   than   scientific   proof.     It   is  most 
probable  that  less  wasteful  exploratory   de- 
velopment is  undertaken  nowadays,  although 
backs  are  longer  and  individual    drift-faces 
more  isolated  from  other  workings,   for  the 
simple  reason  that  the  constantly  increasing 
accumulation  of   data  generally   renders   the 
determination  of  a  fault's  identity  and  influ- 
ence less  and  less  difficult.   How  would    Reef 
Miner '  solve  the  problems  of  faulting,  and 
improve  "  present  methods  ?  "      Perhaps  he 
would  put  in  four  pegs  and  tell  his  Rhodesian 
Kaffir  to  drive.     Then  return  in  three  days, 
trusting  that  the  native's  psychological  pecu- 
liarity in  relation  to  the  circular  would  lead 
him  straightway  to  the  desired  round  pebbles 
of  banket. 

I  fear,  however,  that  your  Krugersdorp  cor- 
respondent's ideas  are  at  times  too  tangled  for 
such  interpretations.  What  encouragement 
can  be  derived  from  his  '  Protest,'  when  he 
would  have  us  believe  that,  since  the  war,  the 
Rand  miner  has  not  been  properly  paid  and 
appreciated,  and  that,  nevertheless,  the  Rand 
has  the  best  miners  from  Europe,  America, 
and  the  Colonies,  because  it  is  the  "  best  mar- 
ket." Here,  at  last,  it  would  appear  "  that 
something  needs  blotting  out,"  even  though  it 
be  merely  one  of  '  Reef  Miner's  '  fundamental 
arguments. 

Ralph  Stokes. 
Cornwall,  November  24. 


Casapaica  Smelter. 

The  Editor  : 

Sir — In  the  July  issue  of  your  magazine  my 
description  of  the  Casapaica  smelter  reads  in- 
coherent. Absence  in  the  interior  has  pre- 
vented prior  correction. 

The  first  three  paragraphs  contains  state- 
ments different  from  those  made  in  my  manu- 
script ;    to  those  who  know  Casapaica  they 
must  appear  inconsistent.  In  1888  the  smelter 
was  treating  silver-lead  ores  from  mines  owned 
by  Backus  &  Johnston,  as  well  as  doing  custom 
work.     The  scarcity  of  lead  ores  induced  the 
owners  to  adopt  copper  smelting.  The  smelter 
and  principal  mines  are  situated  at  Casapaica, 
on  the  Central  Railroad  of  Peru,  95  miles  from 
Callao,  the  seaport.    The  Natividad  mine  is  at 
Morococha  and  is  not  the  chief  mine  of  the 
Backus  &  Johnston  Co. ;  they  hold  50%  interest 
in  this  property,  the  remaining  half  being  held 
by  the  Morococha  Mining  Co.,  which  ships  its 
share  of  the  ore  to  the  smelter  of  the  Cerro  de 
Pasco  Co.     The  ore  is  a  mixture  of  enargite, 
pyrite,andchalcopyriteinanaluminousgangue 
containing  little  or  no  lead  and  zinc.   The  Car- 
men property — not  owned  by  the  Backus  & 
Johnston  Co. — is  at  Casapaica.     On  the  first 
line  of  the  third  paragraph   the   unfortunate 
substitution  of  Natividad  for  Casapaica  makes 
the  description  apply  toconditions  not  existing. 
The  ton  of  2000  pounds  is  used  throughout 
the  paper  ;  the  silver  assays  are  given  in  ounces 
per  ton  of  2240  pounds. 

Lester  W.  Strauss. 
Lima,  November  1. 

[Contributors  are  advised  to  send  type- 
written manuscript  and  to  edit  their  articles 
carefully  before  transmission. — Editor.] 

Estimates  of  Extraction. 

The  Editor  : 

Sir — Regarding  the  subject  of  East  Rand 
troubles,  touched  upon  in  your  valuable  issues 
of  September  and  October  last,  and  setting 
aside  any  financial  or  speculative  views  in- 
volved, it  seems  that  discrepancies  between 
theoretical  and  practical  extractions  actually 
come  as  an  aggravating  factor  in  that  com- 
plicated case. 

It  would  be  interesting  to  know  how  far 
differences  between  calculated  recovery  and 
hard  cash  produced  at  gold  mines  are  expected 
to  follow  any  settled  rule,  in  the  wide  range 
from  scientific  to  rule-of-thumb,  before  neces- 
sitating an  explanation  to  shareholders.  I  be- 
lieve, however,  that  5%  is  a  fair  margin  to 
contend  with,  provided  that  percentage  were 
not,  through  systematic  errors,  always  thrown 


DECEMBER.    1911 


437 


out  on  the  same  side  of  the  truth.  I  should 
also  like  to  point  out  two  such  possible  errors, 
namely,  in  sampling  ore  m  its  various  states 
of  reduction  and  in  weighing  of  assays. 

Sampling,  to  be  reliable,  must  often  be 
done  in  different  ways,  checking  one  against 
another  ;  especially  on  the  Rand,  where  ore  is 
uneven,  as  in  any  ore  containing  free  gold. 
At  a  mine  not  far  from  Krugersdorp,  we  had 
once  to  make  a  rule  to  get  two  samples  of  the 
same  tailing  before  cyanidation,  duplicating 
the  one  already  taken  from  every  car  on  its 
way  from  the  settling  to  the  cyanide  vats,  by 
another  taken  with  a  rod  from  the  charge  in 
place  just  before  treatment.  Previous  to  that 
step,  discrepancies  were  frequent,  and  upon 
investigation  it  was  found  that  the  boy  in 
charge  of  the  sampling,  having  both  his  hands 
occupied  by  taking  a  sample  on  one  side  and 
putting  in  a  dose  of  lime  on  the  other,  would 
select  the  driest  and  cleanest  spot  in  the  car — 
also  the  richest  in  that  particular  case— and 
let  pass  any  slimy  car,  without  sampling  it,  so 
as  not  to  have  to  shake  off  any  wet  stuff  stick- 
ing to  his  scoop  between  takings.  Entreaties, 
then  threats,  elicited  from  him  a  hearty  promise 
to  sample  rightly,  which  he  fulfilled  only  when 
he  thought  himself  watched  by  a  baas.  Even- 
tually that  boy  lost  his  job  and  had  to  be  sent 
to  one  less  responsible,  before  the  extractions 
could  be  put  under  control  again.  Here,  let 
us  note  how  unsatisfactory  often  is  the  posi- 
tion of  the  assayer  or  of  the  analytical  chemist 
at  large,  busy  with  fixing  prices  of  goods. 
When  his  work  goes  all  right,  everybody 
thinks  it  is  only  natural,  but  when  trouble 
arises  he  has  none  but  hard  and  not  always 
well-known  natural  facts  to  fall  upon  for  an 
excuse.  Among  these,  sampling  is  often  done 
in  the  crudest  way,  and  some  gold  mines  would 
do  well  to  imitate  what  is  done  by  copper 
smelters  in  that  line. 

As  to  the  weighing  of  assays  and  of  assay- 
buttons  after  parting,  it  may  be  virtually  called 
the  weighing-out  of  the  whole  production  of 
the  gold  mine,  and  that  is  done  with  only  two 
kinds  of  weight.  One  is  the  various  combina- 
tions of  the  assay-ton  and  subdivisions,  used 
for  assays  before  fusion.  The  other  is  the 
milligram-weights  used  for  the  parted  gold 
buttons,  being  a  wire  rider  and  a  wire  or  foil 
weight  handled  with  pliers.  The  assay-ton 
weights  as  sold  by  the  makers  are  fairly  ac- 
curate ;  with  proper  use  and  ordinary  care 
they  vary  but  little,  certainly  less  than  h%  in 
years.  But  with  the  milligrams,  errors  can 
be  found  of  several  per  cent,  below  or  above, 
either  when  new  or  after  some  use.     I  have 


found  up  to  12%  error  on  some  new  weights, 
and  as  to  changes  brought  on  by  use  it  is  bet- 
ter not  to  broach  the  subject.  Comparing 
carefully  a  whole  set  of  weights  from  the 
milligram  up  to  the  assay-ton  is  a  delicate, 
long,  tedious,  and  instructive  work,  leading 
sometimes  to  amazing  results.  There  is  mild 
foolishness  in  the  combination  of  an  extreme- 
ly sensitive  assay-balance  and  wrong  small 
weights,  for  the  elaborate  clerical  work  based 
upon  results  therefrom  is  bound  to  be  faulty. 
The  only  reasonable  way  out  of  such  a  diiifi- 
culty  is  the  one  advocated  by  A.  A.  Hanks  in 
the  Mining  and  Scientific  Press  of  May  13, 
1911,  to  check  the  weights  periodically,  es- 
pecially the  smallest  ones,  against  standard 
weights  obtained  from  a  Bureau  of  Standards. 
To  minimize  costs,  one  standard  milligram 
and  one  standard  assay-ton  (or  else  half  assay- 
ton)  should  suffice. 

Reverting  to  the  East  Rand  case,  and  sup- 
posing some  errors  imputable  to  weights  to 
have  occurred,  it  is  true  that  different  mines 
contribute  ;  it  is  also  possible  that,  with  the 
overhauling  incidental  to  the  building  up  of 
the  group,  they  all  have  been  provided  with 
new  weights  at  the  same  time.  While  the 
ratios  of  gold  in  residues  to  gold  in  charges 
(sand  or  slime)  or  to  gold  in  ore  fed  to  stamps, 
as  given  by  weighing  respective  buttons  with 
the  same  small  weights,  remain  unchanged, 
whatever  may  the  ratio  of  such  small  weights 
be  to  the  assay-ton  weights,  thus  not  affecting 
the  theoretical  extractions  and  giving  no  hint 
of  trouble  ahead,  it  is  clear  that  any  error  in 
the  ratio  of  incorrect  weights  should  reflect 
itself  upon  the  differences  between  real  re- 
spective weights  of  assay-buttons  of  residues 
and  charges,  corresponding  to  cyanide  bullion, 
and  of  charges  and  ore  entering  the  mill,  cor- 
responding to  amalgam. 

J.    F.    COUTTET. 

Budeliere  Chambon,  France, 
November  20. 

Ball-Mill  Practice. 

The  Editor : 

Sir — In  the  concluding  paragraph  of  my 
letter  appearing  in  your  October  issue  there 
is  a  mistake  in  the  number  of  men.  The 
number  ought  to  be  8,  not  28. 

Donald  F.  Foster. 
Parral,  Mexico, 
November  4. 

[Letters  on  '  Re-precipitation,'  '  Single  Shift 
on  the  Rand,'  and  the  'Origin  of  Petroleum,' 
are  held  over  for  our  January  issue] . 


438 


THE    MINING    MAGAZINE 


PERSONAL 

John  H.  Allen,  of  New  York,  has  been 
at  the  San  Francisco  del  Ore  Mine,  Parral, 
Mexico. 

Philip  Argall  sailed  for  New  York  on 
December  9. 

H.  A.  Barker  sails  on  December  18  for 
Veracruz,  on  his  return  to  Pachuca,  Mexico. 

J.  M.  Bell  has  returned  from  Russia. 

Francis  P.  Bray  sailed  from  Liverpool 
for  the  Gold  Coast  on  December  13. 

C.  Forbes  Brown  left  London  on  Decem- 
ber 6  for  Northern  Nigeria. 

R.  GiLMAN  Brown  has  returned  from  one 
of  his  periodical  visits  to  Kyshtim,  Siberia. 

E.  R.  Buckley  has  opened  an  office  at 
Chicago. 

F.  T.  Byrde  has  accepted  an  appointment 
with  the  Gold  Coast  Estates,  in  West  Africa. 

J.  E.  CLENNELLis  with  the  Creston  Colo- 
rada  company  at  Torres,  in  Mexico. 

B.  I.  CoLLiNGS  has  opened  an  office  at 
Salisbury,  Rhodesia. 

G.  A.  Denny  sailed  for  Veracruz,  Mexico, 
on  December  9. 

H.  S.  Denny  sailed  for  Mexico  on  Novem- 
ber 29. 

James  Douglas  sailed  for  New  York  on 
December  9. 

W.  R.  Feldtmann  and  James  A.  Mac- 
tear  are  back  from  the  Ashanti  goldfield. 

J.  R.  Finlay  has  become  consulting  engi- 
neer with  Charles  Head  &  Co.,  New  York. 

Ernest  K.  Hall,  lately  manager  of  the 
Progress  and  Wealth  of  Nations  mines  in 
New  Zealand,  has  commenced  practice  at 
Sydney  as  consulting  mining  engineer  and 
geologist. 

W.  T.  Hallimond  sailed  by  the  Saxon  for 
South  Africa. 

F.  O.  Harvey  has  returned  from  Spain. 

J.  D.  Henry  left  London  on  December  9 
for  New  York  on  his  way  to  New  Zealand. 

C.  S.  Herzig  will  arrive  in  London  from 
Brazil  on  December  20. 

August  Hoffmann,  of  the  Sissert  es- 
tate, is  at  Stockholm. 

Theodore  J.  Hoover  sailed  for  Australia 
on  November  18. 

J.  C.  Inglis  sails  by  the  Miltiades  on 
December  21   for  Melbourne. 

Caradoc  James  has  returned  from  the 
Gold  Coast. 

W.  B.  Jeffrey  has  returned  to  Oaxaca, 
Mexico. 

Charles  H.  Jones  has  returned  from 
Broken   Hill. 


J.  E.  Jones  has  left  for  Madagascar  to  in- 
vestigate a  nickel  mine. 

A.  Trevelyan  King  is  in  Cornwall. 

William  M.  Knox  has  returned  from 
Eastern  Siberia. 

W.  J.  LoRiNG  is  on  his  way  to  Burma. 

V.  F.  Stanley  Low  has  resigned  as 
manager  of  the  Broken  Hill  Block  10  mine. 

E.  C.  Mackay-Heriot  has  left  London 
for  Central  America. 

L.  S.  Mayreis  has  returned  from  America. 

E.  D.  McDERMOTThasgone  toNicaragua. 
Andrew  McWilliam  has  been  appointed 

to  the  newly-formed  post  of  metallurgical  and 
analytical  inspector  of  steel  for  the  Indian 
Government. 

Ambrose  Monell  was  at  Porcupine  re- 
cently. 

John  Morgan,  of  the  South  Kalgurli,  is 
here  from  Kalgoorlie. 

C.  H.  MUNRO  is  expected  in  London  from 
Eastern  Siberia  at  the  end  of  December. 

F.  Douglas  Osborne  has  returned  to 
England  after  a  visit  to  the  tinfields  of  Swazi- 
land and  the  Northern  Transvaal. 

W.  Pellew-Harvey  has  been  elected  a 
director  of  the  Great  Cobar  company. 

C.  W.  Purington  has  opened  a  branch 
office  at  42  Moika,  St.  Petersburg. 

L.  D.  Ricketts  is  here,  as  adviser  to  the 
Arizona  Copper  Co.,  of  Edinburgh. 

H.  M.  Ridge  is  recovering  from  an  attack 
of  diphtheria. 

H.  P.  Robertson  sailed  for  Brazil  on 
December  16. 

R.  H.  RuNDLE  has  left  London  to  become 
assayer  to  the  Zaaiplaats  Tin  Mining  Co.,  in 
the  Transvaal. 

F.  C.  Smith  has  returned  from  the  Gold 
Coast  of  West  Africa. 

R.  E.  Smith,  of  Vladivostok,  is  at  St. 
Petersburg. 

O.  J.  Steinhart  was  in  Sweden  recently. 

H.  L.  SULMAN  distributed  the  prizes  gained 
by  students  in  the  Sir  John  Cass  Technical 
Institute  on  November  29. 

W.  R.  Thomas  has  left  England  for  New 
South  Whales. 

C.  F.  Trousdell  has  returned  from  the 
Gold  Coast. 

H.  W.  Turner  has  returned  from  Siberia. 

Morton  Webber  has  arrived  from  New 
York  on  a  visit  to  London. 

Horace  V.  Winchell  has  been  examin- 
ing mines  in  California. 

Louis  A.  Wright  is  here  on  his  way  from 
China  to  New  York. 


MINING  IN  MADAGASCAR 


By  T.   DRAPER. 


MADAGASCAR  is  known  to  be  highly      weak  disposition  easily  swayed  by  his  favour- 
mineralized  and  is  generally  regarded 


as  being  possessed  of  great  resources 
Its  mineral  wealth  is  varied  and  affords  oppor- 
tunities for  exploiting  either  base  or  precious 
metals  as  well  as  a  variety  of  precious 
stones.  Previous  to  the  conquest  of  the 
island  by  the  French  in  1895  mining 
was  carried  on  principally  by  the  natives, 
though  a  few  Europeans  succeeded  in 
securing  prospecting  privileges  of  a  pre- 
carious nature.  Security  of  title  was 
dependent  on  the  goodwill  of  the  ruler, 
whose  courtiers  were  ever  ready  to  turn 
to  their  own  benefit  any  discovery  of 
merit,  and  whose  avarice  and  retrogres- 
sive spirit  did  much  toward  discouraging 
the  influx  of  foreign  prospectors.  Even 
missionaries,  to  whose  zeal  the  island 
owes  much,  were  tolerated  rather  than 
encouraged  and  at  times  passed  through 
periods  of  stress  when  life  and  property 
hung  in  the  balance. 

Previous  to  the  year  1868  the  govern- 
ment of  the  country  was  of  a  chaotic 
nature,  periods  of  quietness  and  disorder 
alternating  according  to  the  disposition 
of  the  autocratic  ruling  spirit.  From 
1828  to  1861,  during  the  reign  of  terror 
of  Queen  Ranavalona  I,  the  country  was 
practically  closed  to  Europeans,  and 
persecutions,  directed  more  particularly 
against  converts  to  Christianity  and  those 
who  manifested  aprogressive  spirit,  were 
of  daily  occurrence.  Executions  were 
carried  out  by  casting  the  condemned 
over  the  precipice  on  which  the  Royal 
Palace  at  Tananarive  is  situated.  At 
least  one  European  and  several  native 
missionaries  are  said  to  have  suffered 
this  fate,  though  it  is  not  recorded  whether 
they  underwent  the  ordeal  of  tangena, 
a  poisonous  nut  which  acts  as  an  emetic 
and  which  the  accused  was  made  to  take 
in  the  form  of  a  broth  after  having  pre- 
viously swallowed  three  pieces  of  the 
skin  of  a  fowl :  if  he  vomited  the  bits  of  skin 
he  was  considered  innocent,  otherwise  he  was 
condemnedand  executed.  Whole  villages  were 
subjected  to  this  barbarous  trial.  Ranavalona 
was  succeeded  by  her  son  Radama  II,  who 
evinced  a  more  placable  spirit,  but  was  of  a 


ites,  foreign  and  native.  From  him  an  enter- 
prising French  company  obtained  extensive 
territorial  privileges,  which  eventually  led  to 
his  assassination  by  his  own  subjects  and  to 


■Mainti'ranp 


Madagascar. 


Oleqo  Suaraz 


Scale  of  Miles 


Railways. 
Motor   Roads. 


on  Dauphin. 


the  bombardment  and  occupation  by  the 
French  of  Majunga  and  Tamatave  in  1883 
during  the  reign  of  Ranavalona  II,  her  pre- 
decessor, Queen  Rasoherina,  having  previously 
repudiated  the  concession. 

Within  the  last  year  a  quiet  revival  of  in- 


439 


440 


THE    MINING    MAGAZINE 


terest  in  Madagascar  has  been  taking  place 
and  there  is  an  undercurrent  of  feehng  that 
points  to  important  developments  in  the  near 
future.  A  description  of  the  leading  features 
and  local  conditions  should  therefore  prove  of 
interest. 

With  the  exception  of  the  coastal  regions, 
which  are  low-lying,  the  island  consists  of  an 
extended  inland  plateau  with  an  elevation  of 
some  5000  ft.  above  sea-level.  The  climate 
of  the  interior  is  healthy,  the  scenery  pic- 
turesque and  reminiscent  of  the  high  veld  in 
South  Africa.  The  rainfall  is  moderate,  about 
42  inches  per  annum,  and  occurs  during  the 
summer  months,  from  September  to  May. 
During  this  period  the  coastal  regions  are  un- 
healthy, fever  and  dysentery  being  prevalent, 
but  not  of  a  dangerous  type.  With  moderate 
care  Europeans  experience  no  difficulty  in 
keeping  healthy,  especially  if  periodical  re- 
cuperative trips  are  made  to  the  highlands. 
Blackwater  fever  occasionally  manifests  itself 
but  seldom  proves  fatal.  From  enquiries  made 
on  the  spot,  principally  from  Europeans  whose 
long  residence  enables  their  judgment  to  be 
accepted  without  reserve,  it  would  appear  that 
the  unpleasant  reputation  of  Madagascar  is 
ill-deserved  and  is  based  principally  on  the 
high  mortality  experienced  by  the  French 
troops  during  the  conquest,  when  the  sanitary 
arrangements  left  much  to  be  desired  and 
exposure  was  unavoidable.  Since  then  the 
French  have  laboured  incessantly  to  improve 
conditions  and  are  to  be  congratulated  on  the 
successful  issue  in  regard  to  the  principal 
ports,  Majunga,  Diego  Suarez,  and  Tamatave, 
which  are  now  freed  from  the  dreadful  malarial 
scourges  of  the  past.  Successful  war  is  being 
waged  against  the  mosquito  though  the  preva- 
lence of  water  and  stagnant  pools  renders  pro- 
gress slow.  Madagascar,  like  the  Klondike, 
is  noted  for  the  size  and  myriads  of  its  mos- 
quitos  and  a  night  passed  at  Brickaville  on 
the  way  to  Tananarive  is  an  experience  that 
will  be  remembered  even  by  the  most  case- 
hardened. 

The  coastal  regions,  however,  are  with  few 
exceptions  not  those  in  which  minerals  occur, 
and  the  few  days  spent  in  transit  to  the  in- 
terior are  not  formidable.  Tananarive  is  the 
best  point  of  departure,  being  only  a  24  hours' 
journey  from  Tamatave.  Once  on  the  high- 
lands all  goes  well.  An  excellent  service  of 
motor-cars,  running  over  roads  that  reflect  in- 
finite credit  on  the  administration  of  the  island, 
renders  Miaranarivo,  Antsirabe,  Ambositra 
and  Mevatanana,  accessible  with  comfort  and 
celerity.     From  these  places  any  part  of  the 


mineralized  portion  of  the  island  can  be  reached 
at  the  rate  of  about  25  miles  per  day  by  means 
of  native  bearers.  In  its  early  days  Madagas- 
car was  dependent  entirely  upon  its  water- 
ways and  native  carriers  for  its  transport,  and 
although  the  French  have  accomplished  won- 
ders by  way  of  opening  up  the  island,  never- 
theless, except  in  regard  to  the  main  roads,  the 
early  methods  are  still  in  vogue.  These  are 
slow  and  cumbersome  to  a  degree,  and  withal 
expensive,  but  there  is  no  satisfactory  alter- 
native. For  a  journey  extending  over  a  period 
of,  say,  two  months,  thirty  or  forty  bearers  or 
boiijaiies  will  be  required,  of  whom  from  eight 
to  ten  will  be  used  in  relays  to  bear  the  palan- 
quin, locally  termed  a  filanzane,  and  the 
others  to  carry  the  camping  outfit  and  pro- 
visions. The  camping  outfit  should  consist  of 
a  folding  bed  (with  the  indispensable  mosquito 
curtain),  a  folding  table  and  chairs,  several 
blankets,  sheets,  and  spare  clothing,  a  good 
mackintosh,  and  a  waterproof  sheet.  Tinned 
goods  according  to  taste  are  advisable,  though 
provisions  in  the  form  of  fowls,  eggs,  potatoes, 
etc.,  are  obtainable  at  prices  that  would,  if 
more  generally  known,  cause  a  stampede  of 
all  good  housewives  to  Madagascar,  to  wit : 
eggs  3d.  per  dozen,  fowls  6d.  each,  turkeys 
Is.,  beef  2d.  per  lb.,  rice  id,  per  lb.  Wine  is 
cheap  and  preferable  to  water,  which  is  sel- 
dom above  suspicion.  A  shot-gun  for  quail, 
partridges,  and  guinea-fowl  will  serve  to  pro- 
vide a  change  of  diet.  A  rifle  is  of  no  use  ex- 
cept for  crocodiles  and  for  wild  cattle  on  the 
west  coast  of  the  island.  Packages  are  done 
up  so  as  to  weigh  from  50  to  70  lb.  and  are 
carried  on  a  pole  slung  between  two  bearers. 
A  tin  trunk  for  clothing  and  another  as  a  grub- 
box  are  preferable  to  wooden  ones  in  the  rainy 
season.  A  white  umbrella  lined  with  green 
and  a  pair  of  smoked  glasses  will  afford  relief 
from  the  burning  rays  of  the  sun  and  from  the 
glare,  which  at  times  is  unbearable.  A  tent 
is  a  matter  of  personal  taste.  Villages  are 
frequent  and  shelter  of  a  kind  can  always  be 
obtained,  though  the  surroundings  are  not  al- 
ways of  an  inviting  character.  During  the  dry 
season  villages  are  best  avoided,  as  an  unusual 
number  of  pigs  and  dogs  are  apt  to  render 
night  hideous.  This  outfit,  with  its  huge  re- 
tinue of  bearers,  appears  formidable  enough, 
as  indeed  it  is  as  far  as  expense  is  concerned, 
but  the  only  alternative  is  to  walk  and  court 
disaster.  It  is  advisable  when  a  long  trip  is 
contemplated  to  put  oneself  in  the  hands  of  an 
old  resident  accustomed  to  the  conditions  and 
if  possible  to  secure  one  of  these  as  a  guide 
and  companion. 


DECEMBER,    1911 


441 


Crushing  selected  Ore. 


A  Bateadora, 


^\      V 


A  Family  of  Bateadoras  at  work. 


Illustrating  Native  Methods  of  Mining. 


442 


THE    MINING    MAGAZINE 


Geologically,  Madagascar  presents  many 
features  of  interest.  Only  a  small  portion  of 
its  geology  has  been  correlated  up  to  the  pre- 
sent, principally  by  missionaries,  among  whom 
Barron,  of  the  London  Missionary  Society, 
figures  most  prominently.  Gautier,  the  French 
geologist,  has  also  written  extensively  on  the 
subject,  but  there  still  remains  a  large  and  in- 
teresting field  for  study  to  any  one  desirous  of 
achieving  an  honourable  fame. 

With  the  exception  of  a  comparatively  nar- 
row strip  of  sedimentary  deposits,  represent- 
ing about  one-third  of  the  total  superficial  area 
of  the  island  extending  along  the  western  coast, 
the  greater  part  of  Madagascar  consists  of 
metamorphic  and  associated  non  -  schistose 
rocks  typically  representative  of  the  Archaean, 
or,  in  this  instance,  pre-Carboniferous  period. 
Regional  metamorphism  has,  in  fact,  prevailed 
over  vast  and  monotonous  areas  broken  only 
at  rare  intervals  by  granite  of  an  intrusive 
type,  as  distinct  from  the  associated  granites 
exhibiting  gradual  transition  into  and  affilia- 
tion with  the  gneissic  masses.  Volcanic  in- 
trusions of  recent  origin  are  also  in  evidence 
within  the  metamorphosed  area  and  occur  in 
the  sedimentary  area  on  the  west  coast,  where 
several  volcanic  pipes  and  numerous  diorite 
and  basalt  dikes  have  been  observed.  A  note- 
worthy feature  is  the  rarity  of  white  or  mus- 
covite  mica  in  the  granites  of  Madagascar  and 
the  consequent  scarcity  of  normal  granite. 
The  same  characteristic  feature,  absence  of 
white  mica,  is  also  observable  in  the  gneisses, 
which,  in  addition,  present  the  peculiarity  of 
being  almost  invariably  hornblendic.  Felspar 
is  an  abundant  constituent  of  the  gneisses ; 
the  variety  microcline,  generally  regarded  as 
rare  in  biotite  and  hornblendic  gneiss,  is  not 
uncommon  in  Madagascar.  With  these  ex- 
ceptions, the  Archaean  rocks  of  the  island  call 
for  no  special  comment. 

Turning  to  the  sedimentary  formations, 
which,  as  previously  stated,  are,  except  for  a 
few  isolated  superficial  deposits,  confined  to 
the  west  coast,  these  are  found  overlying  the 
metamorphic  series  unconformably,  dipping 
gently  to  the  west,  whereas  the  schists  are 
titled  at  angles  varying  from  45  to  90  degrees. 
Owing  to  the  rarity  of  fossils  as  well  as  to  the 
limited  number  of  geologists  who  have  taken 
an  interest  in  Madagascar,  it  is  not  possible  to 
relegate  the  sedimentary  formations  to  their 
proper  geological  horizons  with  any  certainty. 
In  the  southern  portion  of  the  island  a  car- 
boniferous formation  has  recently  been  identi- 
fied, while  in  the  middle  west  and  northwest 
the  Jurassic  system  has  been  positively  recog- 


nized, but  Triassic  rocks  are  uncertain,  while 
the  Permian  exists  by  inference  only.  Several 
noted  geologists  have  recently  visited  Mada- 
gascar and  their  researches  will  undoubtedly 
do  much  toward  clearing  points  at  present 
obscure. 

The  prevalence  of  metamorphic  rocks  in 
Madagascar  infers  that  the  island  should  be 
rich  in  minerals,  and  although  its  mineral  re- 
sources are  not  fully  explored  this  inference 
is  confirmed  by  the  discoveries  made  up  to 
date.  Gold,  copper,  iron,  lead,  zinc,  nickel, 
graphite,  mica,  uranium,  asbestos,  and  pre- 
cious stones  are  known  to  occur  in  quantities 
that  should,  and  in  many  instances  do,  permit 
of  profitable  exploitation.  Not  all  of  these 
minerals  are  of  economic  value  at  the  present 
time  but  their  existence  argues  well  for  the 
future  of  the  island.  Coal  measures  have 
recently  been  identified  in  the  south  and  indi- 
cations of  petroleum  are  numerous  in  the  Saka- 
lava  valley. 

Taking  the  minerals  in  the  order  of  their 
importance,  gold,  by  its  wide  dissemination 
throughout  the  metamorphic  region,  promises 
to  develop  into  an  important  asset.  A  glance 
at  the  official  map  showing  the  mineral  distri- 
bution of  the  island  will  confirm  this  impres- 
sion. Fully  one-half  is  labelled  auriferous. 
The  yellow  splash  of  colour  indexed  as  '  gise- 
tnents  d'or"  is  truly  remarkable  in  extent. 
Throughout  the  area  indicated  gold  is  at  the 
present  time  being  mined  by  crude  but  none- 
the-less  successful  methods.  The  ubiciuitous 
batea,  a  relic  of  the  Portuguese  occupation, 
operated  by  the  unskilled  hands  of  a  batea- 
dora  adds  its  little  quota  of  gold  to  an  ever- 
increasing  total.  In  1897  the  output  was  2543 
ounces,  and  at  the  present  time  it  exceeds 
80,000  oz.  per  annum,  nine-tenths  of  which 
owes  its  recovery  to  laborious  panning,  un- 
skilled sluicing,  or  '  gophering.'  In  the  latter 
instance  the  selected  ore  is  crushed  in  wooden 
mortars  by  pestles  shod  with  iron.  The  accom- 
panying photograph  affords  a  good  illustration. 
The  methods  are  ludicrous  but  the  result  is  sig- 
nificant. Up  to  date  there  are  only  two  stamp- 
mills  on  the  island  neither  of  whichhas  justified 
its  installation,  the  larger,  consisting  of  Z5 
stamps  because  of  unskilled  erection,  the  smal- 
ler because  of  antiquity  sublime  and  hoary.  It 
isestimated  that  half  of  the  annualoutput  is  de- 
rived from  sluicing  of  alluvial  terraces  and  the 
remainder  by  bateas  from  streams  and  quartz 
veins.  The  quartz  veins  occur  in  the  schists 
and  gneiss andare  generally  well  defined  bodies 
that  would  repay  exploitation  by  modern  me- 
thods.     Rich   leaders   are    frequent   and    are 


DECEMBER,   1911 


443 


trenched  and  '  fossicked  '   by  the  natives  for 
many  hundreds  of  yards  down  to  a  depth  of 
fifteen  or  twenty  feet.      No  systematic  work 
is  being  done  except  where  several  Europeans, 
hampered  by  lack  of  capital,  are  waging  un- 
successful   war    against    adverse    conditions. 
The  deepest  shaft  is  said  to  be  120  feet.  The 
gold    mming  industry   is   maintained   almost 
entirely  by   the  natives,   who  are  invited  by 
the  owners  of  mining  claims  to  exploit  their 
ground.     The   owners,    generally   European, 
make  no  attempt  to  institute  systematic  de- 
velopment and  are  content  to  purchase  the  gold 
from  the  natives  and  re-sell  at  a  profit.   I  know 
of  several  who  are  earning  from  2^500  to  ^1000 
per  annum  by  this  method.    Naturally,  mining 
carried  on  under  these  conditions  does  not  tend 
either  to  permanency  or  progress.     The  hap- 
hazard methods  of  the  Malagasy  are,  under 
these  conditions,  confined  to  surface  scratching 
and  are  continued  only  as  long  as  the  maxi- 
mum result  can  be  obtained  by  a  minimum 
effort.     When  results  are  no  longer  remunera- 
tive the  natives  shift  to  some  other  part,  en 
masse,  and  leave  the  concessionaire  to  reflect 
mournfully  on  the  wealth  untold,  and  unattain- 
able, under  his  feet.      Lack  of  capital  to  him 
means  lack  of  method,  so  he  too  shifts  ground 
and  starts  again  under  the  same  conditions. 
Unsatisfactory  to  a  degree,  this  method  has 
yet  shown  Madagascar  to  be  highly  auriferous, 
and  a  large  proportion  of  its  inhabitants  are 
engaged  in  shifting  their  ground  from  year  to 
year.     Unfortunately  for  the  country  it  has 
had  several  gold  booms,  engineered  by  un- 
scrupulous adventurers,  that  have  brought  it 
into  evil  repute.     To  make  matters  worse,  the 
Malagasy  are  not  unskilled  in  the  art  of  '  salt- 
ing '  and  several  scandals  are  now  being  lived 
down.      Professional  brethren  who  may  have 
occasion  to  visit  the  island  in  the  future  are 
advised  to  exercise  more  than  ordinary  care, 
especially  when  dealing  with  alluvial  ground. 
The  rivers  of  Madagascar,  especially  those 
on  the  west  coast,  are  highly  auriferous  and 
suitable  for  dredging.     The  base  metals  call 
for  no  special  comment.     Copper,  iron,  and 
lead  are  plentiful,  though  silver  is  rare.    Zinc 
and  nickel  are  known  in  quantity  but  have  not 
yet  been  exploited  on  a  large  scale.    Graphite 
of  good  quality  is  being  exported.      Uranium 
has    recently    been   discovered   and  is   being 
mined  at  Antsirabe.     Tin  and  cobalt  ores  have 
been  found  in  several  localities.     The  precious 
stones  of  Madagascar    comprise   tourmaline, 
garnet,  and  various  others  of  lesser  value,  but 
beryl,  ruby,  and  sapphire,  some  of  which  com- 
mand high  prices,  are  also  found.     The  Mada- 


gascar aquamarine  is  in  demand,  and  recently 
another  variety  of  beryl  found  here,  to  be  called 
morganite,  was  described  in  the  American 
Journal  of  Science.  Diamonds  have  been  re- 
ported and,  as  peridotite  is  known  to  occur,  the 
discovery  of  a  diamond  mine  is  not  improbable. 
Intelligent  prospecting  is  what  the  islandneeds. 
Apart  from  the  military,  the  European  com- 
munity is  small  and  is  engaged  solely  in  com- 
mercial pursuits.  Prospecting  is  done  only 
by  casual  visitors  who  have  m  too  many  cases 
ultimately  victimized  their  friends  on  the  other 
side  of  the  Mozambique  Channel. 

Mining  in  the  strict  sense  of  the  term, 
whether  for  gold,  base  metals,  or  for  precious 
stones,  is  as  yet  unknown  in  Madagascar,  but 
it  may  safely  be  predicted  that  the  near  future 
will  witness  a  complete  change.  It  is  within 
the  bounds  of  probability  that  the  discovery  of 
petroleum  will  give  the  needed  impetus  to  the 
island.  Systematic  boring  for  oil  is  being  con- 
ducted in  the  Sakalava  valley  on  the  western 
side  of  the  island,  where  the  geological  features 
are  such  as  may  lead  to  the  discovery  of  an 
oilfield  at  any  moment.  It  is  reported  that 
small  quantities  of  oil  have  already  been  found 
in  a  well  seven  or  eight  miles  southwest  of  the 
village  of  Folakara.  The  definition  of  the  oil 
belt  seems  to  be  only  a  question  of  time  and 
money.  Large  areas  are  held  for  exploitation 
of  petroleum  and  greater  activity  is  predicted. 
The  import  duties  on  oil  into  France  will  give 
Madagascar  an  advantage  over  the  European 
and  other  oilfields,  while  its  proximity  to  South 
Africa  will  be  in  its  favour. 

The  mining  laws  of  Madagascar  are  liberal 
in  the  extreme,  and  every  encouragement  is 
given  to  legitimate  mining  enterprises.  An 
unsatisfactory  feature  is  that  labour  threatens 
to  be  both  scarce  and  unskilled.  The  native 
population  is  agricultural  and  pastoral  and 
mining  has  not  yet  attracted  the  attention  of 
the  labourer. 


Australian  Iron  Resources  have  re- 
ceived the  close  attention  of  the  New  South 
Wales  Government,  and  F.  W.  Paul,  an  En- 
glish authority  on  iron  and  steel,  has  recently 
been  commissioned  to  examine  the  situation 
and  give  his  views.  His  report  has  just  been 
issued  and  is  entirely  favourable  to  the  estab- 
lishment of  an  iron  and  steel  industry  depend- 
ing solely  on  Australian  ores  and  coal.  He 
considers  that  hematite  pig  iron  could  be  pro- 
duced at  a  cost  of  54s.  per  ton,  steel  rails  at 
£6.  10s.,  and  galvanized  iron  sheets  at  £\6  ; 
the  corresponding  selling  prices  at  works  in 
England  are  £?>,  £6,  and  £l2. 


THE   FINANCE  OF  A  MINE.     VI 


By   M.   H.   BURNHAM. 


IN  the  preceding  articles  I  have  attempted 
to  set  out  the  principles  governing  the 
economics  of  mining  finance,  but  as  several 
months  have  elapsed  between  the  first  and 
the  present  article,  it  may  be  well  to  recapitu- 
late the  views  expressed. 

Premise  No.  7. — The  basic  premise  is  that 
the  engineer  may  not  escape  the  necessity  of 
dealing  with  the  economics  of  finance,  resting 
this  contention  upon  : 

(a)  The  fact  that  flotations  of  any  magni- 
tude place  the  engineer's  name  promi- 
nently in  prospectuses,  thus  by  infer- 
ence making  him  sponsor  not  only  for 
the  cash  outlay,  but  for  the  price  per 
share  paid  by  subscribers. 
ib)  The  necessity  for  the  engineer  acting 
as  negotiator  in  foreign  parts  where 
payment  may,  and  generally  should, 
be  made  in    shares  or  debentures, 
(c)  The  growing  practice  of  placing  engi- 
neers on  company  boards. 
Premise  No.  2. — The  second  premise  ad- 
vanced is  the  ordinary  business  concept  that 
all  sound   calculations  essentially  entail  the 
assumption  of  capital  return,  a  rate  equal  to 
Consols,  and  a  further  rate  as  an  allowance 
for   risk,  counting   from   the  date   of  invest- 
ment. 

The  development  of  the  second  premise  led 

to: 

Development  No.  1 . — Allowance  for  risk  is 
based  on  the  amount  of  relevant  data  obtain- 
able, varying  inversely.  From  a  consideration 
of  data  bearing  on  valuation,  it  was  thought 
possible  to  separate  it,  placing  it  under  two 
heads  : 

(a)   Data  based  on  geological  surmise  only, 
that  is,  wanting  sampling  verification. 
This  may  be  called  '  possible  ore.' 
{b)   Data  from   sampling  the  whole   or   a 
portion  of  the  periphery  of  a  block 
of  ore.     This  may  be  called  '  prob- 
able '  ore. 
As  will  be  seen,  both  are  cases  of  assump- 
tion, the  former  having  to  assume  both  occur- 
rence and  continuity,  while  the  latter  {b)  has 
only  to  assume  continuity  from  the  sampled 
surface  to  the  centre  of  the  block. 

From  the  extra   uncertainty  attaching  to 
{a),  it  was  found  that 


(c)  Sound  practice  permitted  expenditure 

on  exploration  alone,  where  the  basis 

of  valuation   was  merely   geological 

surmise. 

A   further  development  of  Premise  No.  2 

lead  to  the  view  that  as 

{d)   The  risk-rate  in  ordinary  business  en- 
terprises varies    inversely    with    the 
data  available,  therefore  a  block  of 
ore  in  a  mine  should  be  so  valued. 
Hence  : 
[e)  Within  the  limits  set  by  the  dimensions 
of  the   standard   block   the  risk-rate 
applicable  to  each  block  should  vary 
inversely  with   the   number   of   full- 
section  samples  available. 
A  study  of  the  occurrence  of  the  rich  and 
poor  parts  of  a  block  as  shown  by  a  carefully 
prepared  assay-plan  indicate  that : 

Development  No.  2. — Depending  upon  the 
homogeneity  of  the  shoot,  a  ratio  of  sampled 
periphery  to  cubic  contents  exists  for  each, 
to  exceed  which  entails  a  greater  risk  ;  that 
is,  a  standard  block  must  be  determined  having 
dimensions  dependent  upon  the  homogeneity 
of  the  shoot. 

(a)  The   risk-rate   for   the  standard   block 
will  be  the  minimum  for  the  under- 
taking. 
This,  in  general,  means  the  risks  ex- 
terior to  the  mine  itself,  such  as  war, 
pestilence,  famine,  strikes,  losses  in 
marketing  the  metal,  hence  varying 
with  the  nature  of  the  product  and 
geographical  position. 
As  the  risk  varies  inversely  with  the 
number  of  sample-sections  available, 
it  follows  that : 
(6)  Blocks  sampled  on  three,  two,  or  one 
side  may  be  given  a  definite  value 
on  the  basis  of  a  risk-rate  varying  as 
the  ratio  of  the  number  of  sample- 
sections  taken    to  those  available  if 
the  block  were  divided  into   two  or 
more  blocks,  each  of  standard  dimen- 
sions. 
In  those  cases  where  the  capital  is  fixed, 
with  the  profit  per  ton  and  dimensions  of  the 
shoot  known,  the  dividends  to  come  from  one 
year's  exhaustion  of  the  shoots  are  also  known ; 
hence,  as  the  lowest  level  in  the  typical  mine 
may  be  considered  to  be  the  upper  side  of  a 


444 


i 


DECEMBER,    1911 


445 


block  of  ore  of  unknown  vertical  dimension, 
the  risk-rate  must  vary  with  the  depth.  In 
other  words,  the  ratio  of  the  data  available 
from  sampling  the  lower  level,  to  the  data 
necessary  to  insure  a  minimum  risk-rate,  be- 
comes less  and  less  as  the  vertical  dimension 
of  the  block  increases. 

We  thus  come  to  the  position  that : 
Development  No.  3. — Shoot  extension  must 
be  allowed  for,  but  that  this  allowance  will 


course,  is  applicable  only  in  the  event  of  there 
being  no  adverse  geological  data. 
It  follows  from  No.  3  that 
(a)  Ore  lying  below  that  point  determined 
as  the  lower  limit  of  allowable  shoot- 
extension  and  which  may  be  paid  for, 
is  no  longer  '  probable  '  but  becomes 
possible  '  only  and  outlay  other  than 
for  exploration  is  unsound. 
The  above  conclusion  places  this  'possible  ' 


/='L/^N        \_^^ 


^  .3:S^   °ZZM^~  ^i 


Fig.   5. 


PLAN   AND    SECTION    OF   A    TYPICAL    COPPER    MINE. 


depend  upon  the  dividends  available  from  the 
ground. 

As  has  been  set  out,  this  allowance  incor- 
porates not  only  the  length  and  thickness  of 
the  ore-shoot,  but  takes  into  consideration  the 
number  of  levels  available  above  the  lowest, 
as  well  as  the  profit  per  ton.  Otherwise,  the 
allowable  shoot-extension  is  a  function  of  the 
economic  dimensions  of  the  ore-shoot,  not  the 
physical  dimensions  alone.      The  above,  of 


ore  in  much  the  same  category  as  the  '  pos- 
sible '  ore  of  an  outcrop  (see  plan  of  Fig.  5) 
which  promises  ore  below,  but  shows  no 
sample-values  ;  in  other  words,  the  data  may 
warrant  outlay,  but  only  on  exploration  and 
not  for  purchase. 

Evidently,  while  there  may  be  no  essential 
difference  between  outlay  on  purchase  and  on 
exploration,  the  latter  is  the  minimum  ex- 
penditure, in  keeping  with  the  fact  that  where 


446 


THE    MINING    MAGAZINE 


outlay  is  based  on  geographical  surmise  only, 
the  data  also  are  a  minimum. 

Development  No.  4. — Any  outlay,  for  ex- 
ploration or  otherwise,  presupposes  the  exist- 
ence of  orebodies  of  sufficient  economic  mag- 
nitude to  repay  the  capital  and  interest  stipu- 
lated. 

It  follows  from  No.  4  that  whenever  an 
engineer  or  geologist  advises  outlay  on  ex- 
ploration, he  commits  himself  to  the  tacit 
assumption  of  enough  profitable  ore  to  repay 
that  expended  upon  exploration,  development, 
plant,  capital  return,  and  interest. 

From  this  it  becomes  necessary  to  consider 
current  practice  with  regard  to  expenditure 
on  shoot-extension  alone,  outlay  on  this  hav- 
ing a  bearing  on  exploration  expenditure,  and 
Table  IV.  (see  issue  of  August)  was  prepared 
for  this  purpose. 


gage  becoming  operative  on  non-payment  of 
interest  together  with  arrears. 

Fig.  5  will  serve  to  illustrate  a  typical 
copper  mine.  As  will  be  seen  on  the  plan, 
the  areas  A  and  B  represent  the  gossan  or 
portion  of  the  outcrop  originally  occupied 
either  by  pyritic  material  or  altered  by  sub- 
sequent sulphate  solutions  ;  in  any  event,  the 
magnitude  of  the  combined  areas  of  A  and  B 
is  the  first  factor  of  economic  importance,  un- 
less, of  course,  they  carry  profitable  ore. 

Evidently,  if  A  and  B  be  but  a  few  square 
feet  in  area  little  attention  would  ordinarily  be 
paid  to  them  ;  if,  on  the  other  hand,  they  prove 
to  be  of  great  extent  and  the  district  promis- 
ing, both  geologically  and  economically,  one 
might  feel  justified  in  advising  outlay  for  ex- 
ploration. A  careful  man,  however,  would 
not  advise  a  payment  to  vendors  ;  yet,  on  the 


Table  VIII. 


Block 

Net  tons 

Years  of 
Life 

i                                      1 
Years  of  '          m^,  p__f:,          1  Number 
Defer-    |          Net  Profit          ^ofsample- 
inent     i                                     j  sections 

Risk- 
Rate 

% 

Table  V  I                                r 

1 

2 

2A 

3 

3A 

4 

5 

j 

50000          1 

60000  :    1 

10000  1 ;     . 
40000 ) : 

60000          1 
70000  I '      . 
20000  ) , 

2  50000           100 

3  80000        j     75 

4  5000        1     25 

4  40000             80 

5  90000        i     50 
7              50000        '     75 

6  10000        ,     50 

5 

7 
20 

6 
10 

7 
10 

079383 
0*68301 
0*35520 
0*64993 
0*48032 
0*46651 
0*42506 

40000 
55000 

2000 
26000 
43000 
23000 

4000 

Total... 

325000 

j                                                     j 

193000 

Before  comparison  could  be  made,  it  was 
imperative  to  evolve  a  unit  applicable  to  each  : 
this  was  called  the  '  shoot-foot,'  being  based 
on  the  concept  of  the  economic  shoot,  which 


IS : 

(a)  The  number  of  sovereigns  of  profit  ob- 
tained by  exhausting  the  ore-shoots 
at  the  lowest  known  point  to  a  depth 
of  one  foot. 
The  development  of  Premise   No.  2  also 
leads  to : 

Development  No.  5.- — When  dividends  are 
delayed  (or  deferred)  for  a  period,  those  re- 
ceived later  must  make  good  the  loss  of  in- 
terest due  to  such  delay.  In  other  words, 
when  valuing  blocks  of  ore,  the  exhaustion 
of  which  is  delayed  beyond  one  year  from 
date  of  outlay,  sound  calculation  demanded 
that  this  loss  of  interest  must  be  considered. 
In  financial  practice  this  principle  is  recog- 
nized by  the  issue  of  cumulative  shares  and 
by  the  foreclosure  clause  of  debenture  mort- 


other  hand,  so  long  as  expenditure  is  advised, 
it  matters  little  to  those  finding  the  capital  to 
whom  or  for  what  purpose  it  be  expended. 

The  real  point  is  the  tacit  admission  that 
the  minimum  of  data,  that  is,  geological  sur- 
mise unsupported  by  profitable  ore,  calls  for 
the  minimum  of  outlay,  which  of  necessity  is 
that  on  exploration  only.  But  even  this  out- 
lay implies  that  the  capital  expended  on  ex- 
ploration will  be  redeemed  as  well  as  interest 
paid.  In  other  words,  the  minimum  econo- 
mic dimensions  of  the  postulated  orebodies  is 
shown  by  the  magnitude  of  the  outlay  advised 
by  the  engineer. 

As  set  out  before,  a  convenient  unit  is  the 
profit  obtained  (with  a  plant  of  given  capacity) 
from  exhausting  such  an  orebody  or  ore-shoot 
to  a  depth  of  one  foot.  On  this  basis  an 
economic  comparison  of  mines  can  be  made 
independent  of  their  reserves  or  of  their  phy- 
sical magnitude. 

If  the  gossan  on  the  surface  shown  in  Fig. 


DECEMBER,    1911 


447 


5  carried  no  profitable  ore,  expenditure  for 
whatever  purpose  would  entail  the  assump- 
tion of  finding  profitable  ore  in  payable  quan- 
tity, on,  say,  the  line  r  —  s.  And  though  the 
only  gauge  of  the  magnitude  of  a  slice  along 
r  — s  is  the  area  of  A  and  B,  it  is  essential  to 
a  clear  exposition  of  the  promise  of  the  ven- 
ture that  the  economic  magnitude  of  this  slice 
be  set  out  ;  column  6  of  Table  IV  is  interest- 
ing as  showing  the  approximate  magnitude  of 
such  a  slice  through  a  number  of  well  known 
mines.  The  table  also  shows  how  distinct  the 
economic  slice  is  from  the  physical  slice. 

Evidently  the  capital  outlay,  either  on  ex- 
ploration alone,  or  as  expressed  in  the  capital 
of  the  company,  divided  by  the  economic  mag- 
nitude of  the  shoot,  gives  the  assumed  shoot- 
extension  necessary  to  repay  the  capital  alone, 
provided  there  be  no  reserves. 

Turning  to  Block   1   of  Fig.  5,  it  will  be 


^^'>*'m<»iVSVS<'S!^/>IV*!^^^^^^^ 


be  taken  at  5  x  _  or  say  7  per  cent. 

Block  3  will  be  seen  to  be  short  of  the  two 
winzes  thought  necessary  to  prove  the  size  of 
the  lean  patches,  hence,  assuming  a  standard 
square  block  and  an  equal  weighting  for  the 
sampling  data  obtained  from  winzes  and  levels, 
the  eastern  section  should  be  given  a  risk-rate 
of  7%,  like  Block  2,  while  the  western  part 
would  require  one  of  10  per  cent. 

The  weighting  of  Blocks  4  and  5  will,  of 
course,  be  largely  governed  by  the  geological 
evidence,  for,  as  will  be  seen,  the  low-grade 
primary  ore  sampled  at  //"  —  /  and  k  —  l  may  be 
as  shown,  or  they  may  be  parts  of  the  main 
body  as  indicated  by  the  dotted  line.  Under 
such  circumstances  some  would  no  doubt  draw 
the  line  h"  —  p  and  consider  this  the  block, 
allowing  it  a  risk-rate  of  say  10%.  In  these 
cases,  however,  geological  data  may  indicate 


BLOCK. 3/q        ; 

PRESET  r*-r    value' 

olf  4  5,000  ' 


BLOC  K.3 

PRCSCrvT     VJt  LUC 

S  26.00O. 


SLOCK. I. 


p/»rsc/v-r    v/»i.uc 
df  4-0.000 


BLOCK.-?-. 


BLOCK. 2.       +  BLOCK. ZM. 

d6ss.Qoo       I    ''c£  a.ooo 

>^ 


BLOCK. S       .' 
/ 
/ 

'£-*:000/ 


Fig.  6.     DIAGRAMMATIC  SKETCH  OF  MINE.     Solid  lines  =  work  done ;    dotted  lines  =  estimated  boundaries  of  blocks. 


seen  that  a  careful  sampling  of  the  drifts  and 
winzes  will  show  three  patches  of  lower-grade 
ore,  each  of  unknown  extension  into  the  body 
of  the  block.  As,  however,  they  appear  to  be 
small  with  reference  to  the  size  of  the  block, 
that  is,  they  do  not  pass  through  it  either  way, 
the  risk-rate  for  this  block  may  be  taken  as 
the  lowest  allowable  for  the  mines,  let  us  say 
5  per  cent. 

Block  2,  however,  not  having  a  winze  to 
the  east,  may  have  a  bulge  in  the  country- 
rock  ;  hence,  in  default  of  this  winze  only  f  of 
the  data  are  available,  and  the  risk-rate  may 


that  a  greater  weight  should  be  given  to  a 
winze  than  to  a  level ;  in  other  cases  the  op- 
posite might  be  sounder,  the  estimated  general 
habit  of  the  rich  or  lean  patches  being  the 
governing  factor. 

As  will  be  seen,  the  blocks  will  usually  be 
exhausted  at  a  different  time,  hence  a  dif- 
ferent deferment  factor  must  be  allowed  for 
each,  as  indicated  by  Table  \TII. 

The  practical  import  of  the  foregoing  and 
essential  contention  is  that  every  company 
should  publish,  not  only  at  flotation,  but  peri- 
odically,a  small  sketch  (Fig.  6),  something  like 


448 


THE    MINING    MAGAZINE 


Fig.  5,  setting  out  the  estimated  present  value 
of  each  block.  Evidently  the  value  will  vary 
from  time  to  time,  not  only  for  the  blocks  in 
the  process  of  development,  but  for  those  fully 
developed.  It  may  be  asked,  however,  if  this 
variation  in  value  is  not  also  true  of  any  of 
the  assets  of  ordinary  commercial  under- 
takings, from  bankers'  securities  to  the  stock 
of  a  greengrocer. 


THE  BLACKWATER  MINE 

By  HAROLD  SHARPLEY. 

THE  Blackwater  gold  mine  is  situated  on 
the  west  coast  of  the  South  Island  of 
New  Zealand,  and  is  reached  by  a  train 
and  coach  journey  of  43  miles  from  Grey- 
mouth.  The  ore  is  a  banded  quartz  carrying 
coarse  gold,  and  is  extracted  through  two  adits. 
The  ore  is  discharged  from  the  mill-bin  on  to 
grizzlies  set  l4  in.  apart,  the  oversize  being 
fed  by  a  shaking  feeder  into  a  10  by  12  in. 
Blake-Marsden  crusher  capable  of  crushing 
6  tons  per  hour  to  Ij  in.  From  the  crusher 
the  broken  ore  falls  into  the  main  storage  bin. 
The  undersize  from  the  grizzlies  gravitates 
direct  to  the  storage  bin.  From  tests  taken 
it  was  found  that  approximately  10%  of  this 
undersize  would  pass  an  18  -  mesh  screen 
(0'037  in.  aperture)  and  it  is  hoped  at  some 
later  date  to  pass  this  over  a  revolving  screen 
(with  0*037  in.  aperture)  and  by-pass  the  un- 
dersize direct  to  the  amalgamating  tables. 

The  ore  is  fed  direct  from  the  storage  bin 
to  the  30  stamps  by  Nelson  suspended  feeders. 
The  stamps  weigh  950  lb.  when  new,  and  are 
run  at  98  to  100  drops  of  74  to  8  in.  per  minute. 
The  shoes  and  dies  are  9  in.  in  diameter.  The 
mortar  boxes  are  fitted  with  4|-mesh  (0'166  in. 
aperture)  and  18-mesh  (0"037  in.  aperture) 
double  crimped  steel  screens,  sufficient  44- 
mesh  screens  being  used  to  keep  the  16  by 
4  ft.  tube-mill  supplied  with  +  0'037  in.  ma- 
terial for  grinding.  The  pulp  from  any  boxes 
that  may  be  fitted  with  18-mesh  screens  flows 
direct  to  the  distributing  box  above  the  plates, 
while  the  pulp  from  the  44-mesh  screens  gravi- 
tates into  the  boot  of  a  12-in.  bucket  elevator 
which  elevates  the  pulp  16  ft.  into  a  hopper. 
From  here  it  passes  over  a  launder  with  a 
alse  bottom  5  ft.  long  composed  of  18-mesh 
brass  screening.  A  considerable  quantity  of 
the  fine  stuff  falls  through  this  screen,  and 
passes  direct  to  the  distributing  box  over  the 
amalgamating  tables.  The  remainder  of  the 
pulp  passes  into  the  feed  pot  of  a  36-in.  'B.M.' 


revolving  screen  covered  with  18-mesh  brass 
screen  cloth.  The  undersize  passes  direct  in- 
to the  distributing  box  above  the  amalgamat- 
ing tables  while  the  oversize  falls  on  to  a  36-in. 
'  Bunker  Hill '  screen  travelling  at  20  rev.  per 
min.  The  undersize  from  this  screen  goes 
direct  to  the  distributing  box  above  the  amal- 
gamating tables  while  the  oversize  forms  the 
feed  for  the  tube-mill.  This  tube-mill  is  fitted 
with  Brown  liners,  and  flints  are  used.  The 
ground  pulp  is  lifted  by  a  Frenier  pump  to  a 
distributing  box.  The  pulp  is  distributed  by 
goose-necked  pipes  to  launders  which  convey 
it  to  9  amalgamating  tables,  with  a  plate  area 
of  490  sq.  ft.  From  these  plates  the  pulp  tra- 
vels to  8  small  cone  thickeners,  the  thickened 
pulp  being  fed  on  to  four  No.  5  Wilfley  tables. 
The  concentrate  falls  into  a  launder  and  flows 
over  two  small  amalgamating  plates  to  catch 
any  free  gold,  and  thence  to  storage  bins. 

We  intend  ultimately  to  close  the  pulp  cir- 
cuit by  adding  a  10- in.  bucket  elevator  at  the 
discharge  end  of  the  tube-mill  and  elevating 
the  pulp  to  a  height  of  32  ft.  over  another 
'  B.M.'  revolving  screen  to  be  placed  imme- 
diately over  the  present  screen  ;  in  this  way 
any  +  0'037  in.  particles  discharged  from  the 
tube-mill  would  find  their  way  back  again. 

At  present  the  tailing  from  the  Wilfley 
tables  flows  to  two  4  ft.  conical  steel  settlers, 
and  four  wooden  classifiers.  The  conical  steel 
settlers  are  4  ft.  deep  with  an  annular  over- 
flow, and  are  fitted  with  a  diaphragm.  The 
overflow  goes  to  the  slime  dam  and  the  under- 
flow to  the  cyanide  plant.  As  the  cyanide 
plant  is  now  too  small  to  treat  the  quantity  of 
sand  produced  it  is  now  being  increased,  and 
we  propose  to  substitute  four  8-ft.  Callow 
thickeners  for  the  present  steel  and  wooden 
classifiers.  These  will  then  be  placed  in  a 
central  position  above  the  cyanide  plant,  the 
pulp  being  discharged  by  goose-necks  to  a 
travelling  distributor  running  on  a  track  laid 
across  the  tops  of  the  vats. 

The  motive  power  for  this  plant  is  provided 
by  two  6-ft.  Pelton  wheels  with  6  and  9-in. 
buckets,  and  a  suction  gas  engine,  the  latter 
acting  as  an  auxiliary  when  the  water  is  low. 
The  water  for  the  Pelton  wheels  is  conveyed 
in  a  race  a  distance  of  a  mile  and  quarter,  and 
falls  a  distance  of  120  ft.  through  two  pipes 
22  and  18  in.  diameter.  When  full  this  race 
carries  about  636  cu.  ft.  per  minute.  The 
power  absorbed  works  out  at  0'73  effective 
horse  power  per  ton  crushed. 

In  June  last  the  working  cost  was  20s.  4d. 
per  ton  for  4208  tons  crushed.  The  width 
worked  averaged  29  inches. 


MINING  ON  THE  COAST  OF  BRITISH  COLUMBIA 

By  PERCY  WILLIAMS. 

EIGHTEEN  months  since,  encouraged 
and  stimulated  by  promising  discoveries 
in  the  Portland  Canal  district,  the  min- 
ing industry  of  British  Columbia  began  to 
wake  up  after  its  ten  years'  nap  following 
the  Golden  Cache  fiasco  and  the  Whitaker 
Wright  boom.  This  awakening  was  quickened 
by  a  temporary  dullness  in  Vancouver  real- 
estate  operations,  thus  enabling  an  extra  large 
proportion  of  land  speculators  and  brokers  to 
participate,  with  variable  sincerity  and  judg- 
ment, in  the  exciting  business  of  bonding  pros- 
pects, organizing  companies,  and  selling  stock. 
During  this  season  of  artificial  prosperity  some 
seventy  incorporations  were  effected,  chiefly 
concerned  with  the  Coast  and  Portland  Canal 
districts. 

Of  these  promotions,  a  year  and   a   half 
later,  it  may  be  safely  stated  that  half-a-dozen 


449 


450 


THE    MINING    MAGAZINE 


have  proved  successful  in  that  they  have  de- 
veloped prospects  from  the  speculative  stage 
to  the  point  where  they  began  to  exhibit  the 
"  ear-marks  of  a  mine."  Of  these  lonesome 
half-dozen  youngsters  four  or  five  have  made 
spasmodic  ore  shipments,  two  or  three  have 
become  mines  of  real  merit,  and  none  have 
paid  dividends  as  yet. 

The  Marble  Bay  mine  on  Texada  Island 
still  apparently  remains  the  sole  profitable 
producer  along  500  miles  of  coast  line,  with 
the  possible  exception  of  the  Britannia  mine 
on  Howe  Sound  and  two  or  three  private 
leases. 

The  Portland  Canal  Mining  Co.'s  property, 
under  able  management  but  handicapped  by 
lack  of  funds  and  over-capitalization,  gives 
promise  of  soon  becoming  a  regular  and  pro- 
fitable shipper  of  ore  and  concentrate  ;  and 
the  same  may  be  said  of  the  Red  Cliff,  al- 
though the  reports  of  the  latter  company  have 
always  lacked  the  comprehensiveness  of  those 
issued  by  the  management  of  the  Portland 
Canal.  The  Red  Cliff  is  about  to  become  a 
shipper  of  chalcopyrite  ore,  but  no  concise 
statement  has  been  made  public  regarding 
probable  tonnage  and  grade  of  ore  as  de- 
veloped by  the  1100-ft.  cross-cut  and  the  400- 
ft.  rise.  The  Glacier  and  Stewart  properties 
in  the  same  district  are  prospects  located  upon 
strong  veins  of  low-grade  concentrating  ore 
of  commercial  width,  which  is  more  than  can 
be  said  of  the  majority  of  locations  made  in 
that  district  during  the  recent  boom. 

Further  down  the  coast,  at  Observatory 
Inlet,  the  Granby  Consolidated  people  have 
been  drilling  and  prospecting  in  a  business- 
like way  some  great  outcrops  of  pyrrhotite  and 
chalcopyrite,  which  promise  to  furnish  the  low- 
grade  nucleus  for  another  smelting  enterprise. 

Back  of  Prince  Rupert,  around  Hazleton 
in  the  Bulkley  valley  of  the  Skeena  river,  in- 
teresting discoveries  of  silver-lead  ores  have 
been  made  and  some  new  coal  areas  located. 
The  completion  of  the  Grand  Trunk  Pacific 
Railway  now  being  built  through  this  district 
should  enable  some  of  these  prospects  to  be- 
come productive  mines.  So  far  as  known  no 
notable  discoveries  of  large  low-grade  argen- 
tiferous lead  veins  have  been  made,  the  ma- 
jority being  small  galena  veins  assaying  high 
in  silver.  The  part  of  the  Province  opened 
up  by  this  most  northern  of  trans-continental 
roads  is  most  inviting  to  prospectors  and  it 
will  be  surprising  indeed  if  the  next  two  years 
do  not  witness  the  opening  up  of  some  healthy 
rivals  of  the  old-time  producers  of  the  Koote- 
nay. 


Just  below  the  mouth  of  the  Skeena  at 
Princess  Royal  island  the  Surf  Inlet  mines 
are  believed  to  be  of  great  value  and  long  life, 
limited  development  to  date  having  proved 
generous  width  and  large  average  gold  con- 
tents. There  are  probably  no  new  gold  pros- 
pects along  the  coast  that  can  approach  in 
promise  that  of  the  Surf  Inlet  properties  for 
the  same  amount  of  development. 

On  the  Queen  Charlotte  islands,  60  miles 
off  the  British  Columbian  coast,  considerable 
prospecting  has  been  done  along  the  shore, 
but  so  far  the  timber-cruisers  seem  to  have 
had  the  best  of  it  as  far  as  penetrating  to  the 
interior  of  the  island  is  concerned.  Much 
coal  land  has  been  staked  and  several  coal 
companies  organized  that  have  done  more  ad- 
vertising of  stock  than  they  have  of  boring  for 
coal.  The  occurrence  of  coal  here  has  been 
generally  known  for  50  years,  and  is  of  wide 
distribution  on  the  Queen  Charlotte  group,  but 
little  or  no  drilling  has  been  done  to  determine 
the  extent  of  the  faulting  and  disturbance 
caused  by  the  excessive  igneous  intrusions  in 
this  area. 

At  Skidegate  Inlet,  on  Queen  Charlotte 
island,  is  located  the  Ikeda  mine,  formerly  a 
producer  of  consequence,  which  was  sold  by 
its  Japanese  owners  a  year  ago  and  has  since 
been  drilled  by  a  Vancouver  syndicate  that 
subsequently  made  an  unsuccessful  effort  to 
finance  the  property,  presumably  upon  the 
results  revealed  by  the  diamond-drill  holes, 
although  their  prospectus  did  not  detail  the 
results  of  boring  operations. 

Farther  south  and  east  of  the  Coast  range, 
on  the  mainland,  in  the  Eastern  Nanaimo  and 
Western  Clinton  divisions,  in  the  vicinity  of 
Chilco  and  Tatlayaco  lakes,  several  gold,  sil- 
ver, and  antimony  discoveries  are  reported  as 
occurring  along  the  general  contact  of  the 
Coast  range  plutonics  and  eruptives  with  the 
sedimentary  rocks  of  the  interior  divisions. 
The  region  is  extremely  favourable  to  the  ex- 
istence of  auriferous  veins  but  it  has  been  little 
prospected,  being  only  accessible  by  a  round- 
about journey  from  Vancouver  of  some  500 
miles,  mostly  wagon-road  and  trail.  When 
the  Provincial  government  builds  a  trail  from 
tide-water  at  the  head  of  Bute  inlet  to  Tatla- 
yaco lake,  60  miles,  there  will  be  more  pros- 
pecting in  this  area.  Indeed,  this  condition 
of  inaccessibility  from  adjacent  tide-water  pre- 
vails all  along  the  immediate  interior  country 
comprising  the  eastern  slope  of  the  Coast 
range.  Numerous  and  deep  salt-water  inlets 
and  fiords  indent  the  coast  -  line  for  miles, 
cross-cutting,   in   some   cases,  almost  to   the 


DECEMBER,    1911 


451 


THE    COAST    RANGE    OF    BRITISH    COLUMBIA. 


LOGGING    CAMP    ON    MACKENZIE    SOUND,   B.C. 


6—5 


452 


THE    MINING    MAGAZINE 


backbone  of  the  Range.  Yet  the  rivers  that 
define  the  passes  and  clefts  in  this  lofty  bar- 
rierof granite  mountains  find  theirway  through 
miles  of  impassable  box  canons  and  thence 
westward  and  downward  through  the  almost 
impenetrable  bush  and  timber  to  salt  water. 
Thus  the  prospector  fresh  from  Tonopah. 
Goldfield,  Arizona,  the  Australian  bush,  and 
the  South  African  veldt,  balks  at  the  coast- 
range  barricade  of  the  British  Columbian 
mainland  and  will  continue  to  leave  it  alone 
until  the  Provincial  government  lends  a  hand 
or  the  aeroplane  becomes  perfected — as  either 
one  or  the  other  is  a  necessity  in  the  rapid  de- 
velopment of  the  guarded  interior  adjacent  to 
and  yet  so  far  from  the  coast.  The  interior 
of  British  Columbia  is  one  of  the  few  unex- 
plored areas  of  North  America  where  a  white 
man  can  live,  and  its  geological  conditions  are 
much  more  favourable  for  the  occurrence  of 
the  precious  metals  than  upon  the  western  or 
sea- ward  slope  of  the  Coast  range,  where  there 
is  less  area  of  acid  porphyries  and  older  sedi- 
mentaries  and  more  of  broken,  distorted  lime- 
stone, slate,  schist,  and  unfissured  granite. 

Farther  yet  to  the  south  along  the  coast 
near  the  United  States  boundary,  and  80  miles 
inland  from  Vancouver  lies  Steamboat  moun- 
tain, at  the  headwaters  of  the  Skagit  river.  A 
year  ago  this  section  was  the  scene  of  reported 
fabulous  gold  strikes  in  formation  "just  like 
Goldfield  Consolidated."  These  reported 
strikes  caused  an  immediate  furore  among 
wide-awake  Vancouver  promoters.  During 
the  winter  providential  snow-falls  delayed 
reputable  investigations  and  it  was  only  the 
coming  of  the  glad  spring-time  that  enabled 
Steamboat  mountain  to  be  classified  with  the 
famous  '  mountain  of  gold  "  discovered  and 
undiscovered  again  at  Bear  river  above 
Stewart  a  year  ago. 

Vancouver,  dyspeptic  already  from  a  too 
steady  diet  of  premature  mining  booms,  needed 
only  the  Steamboat  Mountain  fizzle  to  deliver 
the  last  puncture  to  her  cherished  dreams  of 
mineral  supremacy.  This  "  mineral  suprem- 
acy "  seems  bound  to  come  but  not  until  the 
Coast  country  is  systematically  explored  with 
the  diamond-drill  and  the  interior  districts  are 
rendered  more  accessible  to  tide-water  by 
means  of  railway  lines.  The  Government  has 
been  generous  in  its  appropriations  for  roads 
and  trails,  but  the  country  is  large  and  the  agri- 
cultural interests  are  clamouring  loudly  for  at- 
tention, too  ;  therefore  development  of  trans- 
port facilities  will  be  slow.  Causes  of  mining 
failures  in  the  past  in  accessible  districts  are 
largely  due  to  erratic  orebodies  and  insuffi- 


cient use  of  the  diamond-drill,  combined  with 
the  reluctance  or  inability  of  operators  to  pro- 
vide either  for  high-class  engineering  talent  or 
sufficient  capital. 

Melting  Metals  at  the   Mint— In  the 

yearly  report  of  the  Master  of  the  Mint  par- 
ticulars are  given  of  the  new  gas  furnaces 
used  for  melting  metals.  Many  experiments 
had  been  made  with  electric  and  oil  furnaces 
when  a  change  from  coke  furnaces  were  first 
contemplated,  but  these  were  not  found  so 
suitable  as  those  using  gas.  In  the  experi- 
ments with  ordinary  town  gas  a  variety  of 
systems  were  tested,  involving  the  use  of  gas 
at  ordinary  and  high  pressures,  combined  with 
variations  in  the  pressure  of  the  air.  The 
burner  ultimately  adopted  was  made  by  S.  N. 
Brayshaw,  of  Manchester.  For  the  Brayshaw 
burners  in  use  at  the  Mint  the  gas  is  taken  at 
the  ordinary  pressure  in  the  main  (about  3  in. 
of  water),  and  mixed  with  air  from  a  power- 
ful blowing-engine  at  about  2  lb.  pressure. 
With  care  the  noise  of  these  burners  can  be 
reduced  sufficiently  to  be  unobjectionable. 
The  furnace  linings  compare  favourably  with 
those  hitherto  used  for  coke  in  regard  to  en- 
durance, and  the  crucibles  used  for  gold  are 
found  to  last  longer,  each  crucible  serving  for 
an  average  of  eighteen  heats,  as  against  twelve 
when  coke  is  used.  The  adoption  of  gas  as  a 
fuel  in  place  of  coke  has  been  accompanied 
by  several  incidental  economies,  and  it  is  in- 
teresting to  note  that  the  present  charge  for 
fuel  averages  about  4jd.  per  cwt.  of  standard 
gold  bullion,  as  against  7d.  when  coke  was 
used.  It  should  be  added  that  the  fuel  needed 
to  warm  the  furnace  in  the  morning  has  been 
eliminated  ;  but,  including  this,  the  cost  rarely 
exceeds  5d.  per  cwt.  on  a  day's  work.  During 
1910  the  Mint  installed  sixteen  gas  -  heated 
furnaces,  each  capable  of  taking  a  400-lb. 
crucible,  and  fired  with  Brayshaw  gas-burners. 
These  sixteen  furnaces  have  a  maximum  ca- 
pacity of  2f  tons  of  sterling  silver,  or  2l  tons 
of  bronze  per  melt,  and  four  melts  of  silver, 
or  three  of  bronze,  can  be  made  in  an  ordinary 
working-day  of  10  hours.  Five  furnaces  simi- 
larly gas-heated,  but  of  a  smaller  size,  are  in 
use  for  melting  gold.  It  will  be  seen  that  a 
substantial  saving  in  cost  of  fuel  has  been 
effected  by  the  use  of  gas.  The  incidental 
economies  are  still  greater.  The  cost  of  cart- 
ing and  handling  both  coke  and  clinker  is 
saved,  and  the  room  formerly  required  for 
the  storage  of  them  is  set  free.  The  expen- 
diture on  crucibles,  which  is  a  large  item,  has 
been  reduced  bv  33%. 


OIL   INDUSTRY  OF   ROUMANIA 


By  R.  C.  N.  TWITE. 


HAVING  regard  to  the  large  amount  of 
capital  now  being  invested  by  the  public 
in  oil  companies,  it  is  surprising  that  so 
little  attention  has  been  paid  to  Roumania. 

Geographically,  this  country  is  well  situated 
for  exporting  oil.  It  is  bounded  on  the  east 
by  the  Black  Sea,  with  the  port  of  Constanza, 


The  extent  to  which  this  oil  industry  has 
grown  is  shown  by  the  following  official  sta- 
tistics : 


Year  Tons 

1870 11,649 

1890 53,300 

1900 250,000 

1905 614,870 


Vear  Tons 

1908 1,147,727 

1909 1,294,483 

1910 1,352,289 


and  on  the  south  by  the  Danube,  with  the  port 
of  Galatz.  A  complete  system  of  railways 
traverses  the  country.  From  London  it  takes 
about  four  days  to  reach  Bucharest,  either  by 
way  of  Berlin  or  Vienna.  The  service  is  good, 
and  a  journey  can  be  made  without  discom- 
fort. From  Bucharest  it  is  only  a  couple  of 
hours  run  to  the  oilfields  in  the  Prahova  dis- 
trict, which  at  present  produce  the  bulk  of  the 
Roumanian  oil. 


From  the  aboxe  figures  it  will  be  seen  that  the 
production  has  more  than  doubled  during  each 
quinquennial  period  since  1900. 

In  comparison  with  the  world's  output  of 
oil,  this  production  does  not  seem  remarkable, 
but  it  must  be  remembered  that  the  result  is 
obtained  from  comparatively  shallow  borings. 
What  the  annual  production  will  be  when  the 
deep  wells  are  drilled  is  for  the  future,  but  if 
the  deep  Galician  wells  are  any  criterion,  then 


453 


454 


THE    MINING    MAGAZINE 


Roumania  will  take  a  high  place  among  oil- 
producing  countries. 

The  Government  returns  of  last  year  show 
that  Roumania  exported  oil  and  oil  products 
to  the  value  of  over  40  million  francs  or  roughly 
;^1, 600,000.  This  large  sum  was  obtained 
from  the  export  and  sale  of  581,256  tons,  made 
up  as  follows  : 

Tons 

Crude  oil,  residue,  and  mineral  oils 116,223 

Petrol,  illuminant,  and  distillate 339,282 

Benzine,  crude  and  refined 125,751 

Each  of  these  products  shows  an  increase 
as  compared  with  the  previous  year.  The 
most  striking  was  shown  by  the  crude  oil, 
residue,  etc.,  which  mounted  from  49,715  to 
116,223  tons,  or  more  than  doubled. 

The  oldest  accounts  show  that  oil  was  ex- 
tracted in  the  Buzeu  and  Moldavia  districts, 
which  form  the  northern  part  of  Roumania. 
There  the  oil  is  got  from  hand-dug  pits,  which 
are  oval  in  shape  and  lined  with  wickerwork 
to  keep  them  open.  These  pits  often  have  a 
depth  of  200  metres.  They  still  continue  to 
yield  oil,  but  have  been  quite  eclipsed  by  pits 
in  the  Prahova  district.  Here  the  method  of 
sinking  is  quite  different.  The  pits  are  usually 
square  shafts  one  metre  long  and  one  metre 
wide.  They  are  lined  with  oak  staves  one 
metre  long  by  14  cm.  wide,  costing  at  present 
24  francs  per  hundred.  The  cost  of  sinking 
varies  with  the  depth.  They  are  sunk  under 
contract  by  peasants  who  specialize  in  this 
class  of  work.  Owing  to  gas  and  quicksand, 
fatal  accidents  are  common. 

This  method  of  winning  the  oil  has  now 
been  superseded  by  mechanically  drilled  bor- 
ings which  go  to  much  greater  depths  than  is 
possible  with  hand-labour.  The  systems  now 
used  are  the  American  cable,  and  a  modifica- 
tion of  the  Canadian  system  with  light  iron 
rods.  When  a  site  has  been  chosen  for  the 
new  boring,  and  the  necessary  permission  ob- 
tained from  the  Department  of  Mines,  a  pit  is 
dug.  The  depth  may  be  anything  from  30  to 
100  metres  according  to  the  ground  and  the 
requirements  of  the  operator. 

If  only  a  shallow  depth  is  needed,  then  an 
ordinary  windlass  is  rigged  to  haul  out  the 
dirt  and  lower  the  workmen.  To  obtain  venti- 
lation, a  large  blacksmith's  bellows  is  fixed  at 
the  side  of  the  pit,  and  from  its  nozzle  the 
pipes,  made  of  tinned  iron,  are  extended  into 
the  pit.  As  the  depth  increases,  more  piping 
is  added. 

For  a  depth  of  over  30  metres,  a  horse-whim 
is  used  in  the  place  of  a  windlass,  and  if  the 
gas  is  strong,  two  bellows  may  be  worked  to 
supply  ventilation.      To  supply  light  to  the 


miner,  a  mirror  is  fixed  so  that  the  rays  of  the 
sun  are  reflected  down  the  pit.  The  miner  has 
a  safety  line  lashed  around  him  so  that  incase 
he  becomes  '  gassed  '  or  unconscious,  he  can 
be  immediately  hauled  to  the  surface.  The 
timbering  is  done  from  the  bottom  as  the  work 
proceeds,  the  miner  excavating  on  one  side  at 
a  time,  putting  in  a  stave  and  going  round  and 
round. 

As  soon  as  the  required  depth  is  reached, 
the  derrick  is  erected,  machinery  installed,  and 
drilling  commenced.  It  is  usual  to  commence 
the  bores  with  casing  having  a  diameter  of 
400  to  500  mm.  The  casing  used  for  the  first 
two  strings  is  rivetted,  and  the  rest  is  hermeti- 
cally sealed.  The  rivetted  casing  is  bought  in 
the  country,  but  the  hermetical  is  imported 
from  Germany. 

In  the  Moldavia,  Buzeu,  and  northern  parts 
of  Roumania,  the  land  is  held  by  large  owners, 
and  the  estates  are  extensive.  In  the  Pra- 
hova district,  the  land  mostly  belongs  to  peas- 
ants, whose  original  holdings  were  fairly  large, 
but  owing  to  division  among  their  descen- 
dants, and  through  inter-marriage,  these  hold- 
ings have  been  subdivided  into  plots  of  one, 
two,  and  three  acres.  When  the  land  was 
distributed  amongst  the  peasants,  a  map  was 
made.  This  map,  however,  has  not  been 
brought  up  to  date,  and  great  confusion  has 
ensued. 

These  peasant  proprietors  are  not  allowed  to 
sell  their  land  to  foreign  subjects  or  companies, 
so  they  lease  their  mineral  rights  for  terms  of 
29  years  and  less.  Granting  of  leases  has  led 
to  a  great  deal  of  fraud  and  lawsuits,  as  often 
the  peasant  sells  his  rights  two  or  three  times 
over.  The  concessions  are  merely  contracts, 
and  as  such  are  entered  in  the  official  books  of 
the  Prahova  Tribunal  ;  there  is,  however,  no 
official  examination  to  prevent  fraud.  To 
minimize  this,  the  Government  in  1904  passed 
the  Consolidation  Act,  whereby  an  examina- 
tion is  made  on  the  spot  by  the  officials,  and 
if  it  be  found  that  the  particulars  given  in  the 
concession  are  correct,  the  plot  is  consolidated 
to  the  buyer,  and  the  title  made  absolute.  To 
consolidate  a  concession,  the  following  is  the 
procedure  :  First,  a  petition  has  to  be  pre- 
sented to  the  district  Tribunal,  praying  that 
the  plot  be  consolidated  at  the  same  time,  the 
necessary  taxes,  fees,  and  costs  being  paid. 
The  judge  then  has  to  appoint  a  day  for  the 
public  investigation,  not  earlier  than  one  month 
or  later  than  two  months.  During  this  inter- 
val, the  petitioner  has  to  deposit  a  plan  of  the 
plot  at  the  Tribunal.  Fifteen  days  before  the 
date  fixed,  an  official  notification  with  full  par- 


DECEMBER,    1911 


455 


ticulars  must  be  published  in  tlie  official  Moni- 
teur,  in  the  local  paper,  and  it  must  be  cried 
three  times  in  the  commune  where  the  plot  is, 
and  posted  in  the  mayor's  court.  Immediate 
neighbours  must  be  subpcened  to  attend  the 
investigation,  as  well  as  the  contestants.  On 
the  appointed  day,  the  investigation  is  held  in 
the  commune,  where  the  plot  is;  the  following 


Boring  irith  Drilling  Bit. 

Government  officials  being  in  attendance : 
senior  President  and  senior  Secretary  of  the 
Tribunal,  county  Judge  of  the  district,  senior 
Inspector  of  Mines  for  the  district,  the  Mayor 
of  the  commune,  his  Secretary  and  Precepteur. 
The  plot  is  visited,  evidence  is  taken,  and 
the  verdict  given  in  three  days.  If  the  peti- 
tioner has  a  valid  title,  then  the  concession  is 


It  cannot  be  too  clearly  pointed  out  that 
the  concessions  granted  are,  until  consolidated 
by  the  Government  officials,  simply  contracts, 
which  can  be  broken  by  the  peasants,  and 
often  are,  and  that  redress  is  difficult  to  obtain. 
These  concessions  give  right  of  entry  to  the 
land  and  specify  the  amounts  to  be  paid  for 
damage  to  trees,  houses,  and  roads. 


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Sinking  a  Hand-dug  Pit. 

Nearly  all  the  promising  oil-land  has  been 
taken  up  by  speculators  who  have  got  it 
cheaply  from  the  peasants.  Speculators  then 
sell  it  to  the  operating  companies  at  a  hand- 
some profit,  and  fix  a  royalty  on  the  oil  pro- 
duced. This  royalty  goes  as  high  as  10%  on 
the  total  production.  The  Government  also 
charges  a  royalty  of  1%  on  all  oil  produced. 


Wooden  Beservoir. 

consolidated  to  him,  and  an  act  drawn  giving 
him  a  good  title.  All  concessions  and  con- 
solidations are  published  in  the  Government 
official  publications,  which  clearly  state  who 
are  the  owners,  the  concessionaires,  terms  of 
the  concession,  and  official  numbers. 


Roumanian  Peasants. 

The  oil  measures  in  Roumania  are  nearly 
all  found  in  the  anticlinal  folds  of  Tertiary 
strata,  which  are  parallel  to  the  Carpathian 
mountains,  and  outcrop  in  succession  from 
the  mountains  toward  the  Danube  plain.    On 


456 


THE    MINING    MAGAZINE 


the  Prahova  plains,  these  anticHnes  are  known 
to  exist,  but  are  covered  over  by  recent  de- 
posits. In  the  hilly  country  the  strata  are 
exposed  and  can  be  traced.  In  this  district, 
the  anticlines  are  parallel  to  one  another,  and 
have  an  east-west  direction  with  a  tendency  to 
turn  toward  the  north  with  a  variation  of  from 
10  to  30  degrees,  the  eastern  ends  having  the 
greatest  variation.  Some  of  the  anticlines 
can  be  traced  over  long  distances,  as  for  ex- 
ample, the  great  Campina  group  of  parallel 
anticlines,  extending  from  Draganeasa  to 
Apostolache,  a  distance  of  60  kilometres. 

As  is  usual  in  other  regions,  the  maximum 
quantity  of  petroleum  is  found  in  approaching 
the  anticlinal  axis.  The  really  developed  oil- 
fields at  present  producing  the  bulk  of  the 
Roumanian  oil  are :  Campina,  Bustenari, 
Moreni,  and  Boicoi-Tzintea.  Besides  these, 
a  large  number  of  smaller  fields,  whose  area 
and  capabilities  have  not  yet  been  determined, 
have  demonstrated  from  trial  borings  that  they 
can  produce  oil  in  payable  quantity.  For  ex- 
ample, Apostolache,  Filipeshti  de  Padure,  and 
Vulcanesti. 

The  Campina  oilfield  was  the  first  to  be  de- 
veloped on  modern  lines,  and  for  many  years 
was  the  premier  oilfield  of  Roumania.  It  is 
notable  for  the  number  and  productiveness  of 
its  great  gushers  and  for  the  reliable  yield  of 
its  wells,  over  its  entire  area  and  during  many 
years.  The  petroliferous  strata  are  of  Lower 
Pliocene  and  Upper  Miocene  age  with  two 
principal  oil-horizons. 

The  Bustenari  is  a  collection  of  fields  that 
continually  expand.  It  is  the  direct  continu- 
ation of  Campina  to  the  east.  For  many  years 
it  was  the  greatest  oil- producer  in  Roumania, 
but  the  yield  has  sensibly  diminished  during 
the  last  three  years,  owing  to  the  new  exten- 
sions not  being  so  rich  as  the  central  portion. 
The  geology  is  complicated.  The  petroleum 
is  yielded  by  the  Meotic  (lowest  Pliocene)  and 
the  Upper  Oligocene  strata.  The  wells  yield 
a  steady  production. 

The  Moreni  oilfield  last  year  secured  first 
place  for  total  production,  and  for  the  last 
three  years  it  has  also  yielded  the  highest  pro- 
duction per  well.  This  field  has  as  yet  a 
limited  area,  and  many  trial  wells  sunk  have 
encountered  thick  deposits  of  salt.  These 
wells  have  been  completely  barren. 

The  Boicoi-Tzintea,  eight  miles  south  of 
the  Campina  anticlines,  is  a  system  parallel  to 
the  Campina.  From  later  investigations  there 
seems  to  be  two  anticlines,  the  strata  dipping 
at  a  high  angle.  Faulting  is  noteworthy. 
Hence  wells  right  off  the  ridges  have  to  go 


deep  to  strike  oil.  But  the  wells  are  prolific 
producers  of  an  oil  inferior  to  that  of  Campina 
and  Bustenari. 

The  following  table  shows  the  approximate 
annual  yield  per  well  in  different  parts  of  the 
Prahova  district. 

Wells  Yield  per  well 

1909         1910  1900             1910 

Oilfield                           Number  Tons 

Campina 99         112  3143         2976 

Bustenari 464         467  848            683 

Moreni 50            48  7395          7135 

Boicoi 10            14  1974          1912 

Tzintea 10           22  11616         5274 

Pacuretz 1              3  1360           348 

Bordeni  Parsaui 3             3  1687         1738 

Most  of  this  oil  is  obtained  by  pumping,  but 
in  certain  fields  large  gushers  exist.  These 
gushers,  however,  die  away  in  from  6  to  12 
months  and  then  the  wells  require  pumping. 
As  the  oil  is  obtained  from  the  wells  it  is  run 
into  settling -tanks  and  thence  into  storage- 
tanks.  In  many  cases  the  tanks  are  built  of 
wood,  with  a  retaining  wall  of  earth  or  clay, 
covered  by  wickerwork.  This  earthen  wall 
serves  as  a  protection  for  the  wood  against 
sudden  changes  in  the  climate,  and  also  re- 
tains the  oil  in  case  of  fire. 

The  measuring  and  storage  tanks  are  con- 
structed of  iron  and  steel.  The  various  com- 
panies convey  the  oil  through  a  network  of 
underground  pipe  -  lines  to  the  railway  and 
thence  to  the  refineries.  The  larger  refineries 
have  also  their  own  pipe-lines  and  buy  direct 
from  the  producers.  In  the  newer  fields  the 
pipe-lines  will  have  to  be  constructed  and  con- 
cessions obtained  from  the  Government. 

The  charge  for  conveying  the  oil  is  accord- 
ing to  distance,  besides  a  fixed  allowance  of 
lh%  for  impurities  and  water.  On  receipt  of 
the  oil  by  the  pipe-line  company,  it  is  measured 
and  a  coupon  given  to  the  producer.  This  is 
easily  negotiable  and  is  as  good  as  cash.  Con- 
tracts are  made  for  the  whole  production  from 
a  well  or  plot  for  months  in  advance.  The 
pipe-lines  are  laid  along  the  roads  as  much  as 
possible.  Tank-cars  are  also  used.  Over  2000 
of  these  are  now  in  use  on  the  railway  systems 
for  conveying  oil  and  refinery  products. 

The  Roumanian  refineries  are  able  to  treat 
over  2,000,000  tons  of  crude  oil  per  annum. 

Some  of  the  refineries  are  enlarging  their 
plants.  The  products  obtained  may  be  classi- 
fied as  follows : 

(1)  crude  and  rectified  benzine  ; 

(2)  lamp  and  distilled  petroleum ; 

(3)  residues,  crude  gas,  and  mineral  oils. 
In  a  consular  report  for  1910  it  is  stated: 

"  The  exports  of  petroleum  increased  by  about 
134,000  tons  in  1910,  the  increase  being  prin- 


DECEMBER,    1911 


457 


cipally  in  refined  oil  and  residues.  France  is 
the  principal  importer,  the  United  Kingdom  is 
second,  and  Egypt  third.  The  quantities  ex- 
ported in  bulk  through  the  State  petroleum 
reservoirs  at  Constanza  were  as  follows : 

1909  1910 

Tons  Tons 

Benzine 93,924         93,327 

Refined  oil 137,624  236,109 

Distilled  (including  crude  oil)..   68,173         86,949 
Residues 6,212         58,626 

Total 341,933       475,011 

In  addition  to  the  exports  in  bulk,  about 
30,000  tons  were  exported  in  tins  and  barrels. 
No  reliable  figures  are  obtainable  regarding 
the  countries  of  destination." 


MINE  SAMPLING 

By  S.   F.   SHAW. 

IT  would  be  impossible  to  lay  too  great  stress 
on  the  importance  of  systematic  mine  sam.p- 
ling,  and  recording  of  the  assays,  whether  it 
be  during  development  work  alone,  or  whether 
regular  mining  operations  are  being  carried  on. 
It  is  not  enough  to  take  many  samples,  for  un- 
less there  be  a  simple  manner  of  recording 
these  same  samples  much  of  their  value  would 
be  lost,  especially  after  a  period  of  a  few 
months.  Properly  kept  records  would  be  of 
great  value  even  after   the  lapse  of  several 


CYANIDE   PLANT  AND   MILL    OF  THE  MONTEZUMA   MINES   OF  COSTA  RICA. 


It  should  be  borne  in  mind  that  a  great 
number  of  factories  and  industries  employ 
only  oil-fuel,  as  crude  oil,  residue  and  benzine 
are  procurable  locally  from  the  refineries.  The 
increase  in  the  employment  of  this  fuel  is  be- 
coming more  pronounced  every  year.  More 
than  half  the  locomotives  on  the  railways  are 
fitted  for  oil  consumption.  Factories,  passen- 
ger steamers,  and  river  craft  also  employ  it. 

The  Government  is  doing  a  great  deal  to 
foster  and  aid  the  petroleum  industry.  Al- 
though there  is  a  high  protective  duty  on  most 
imports  into  the  country,  quite  a  long  list  of 
machinery  and  appliances  required  for  the  in- 
dustry are  permitted  to  enter  free  of  duty. 

A  project  is  in  hand  for  linking  the  oilfields 
with  the  port  of  Constanza  by  a  long  pipe-  line. 
This  would  give  the  industry  a  great  impetus. 


years,  whereas  a  mere  list  of  assays  might  not 
only  be  useless  but  even  misleading. 

In  this  article  a  description  of  the  method 
in  use  at  the  Montezuma  Mines  of  Costa  Rica 
will  be  given  together  with  the  necessary  illus- 
trations. All  records  are  kept  on  loose-leaf 
forms,  as  this  permits  the  keeping  of  a  con- 
tinuous record  for  several  working-places  with- 
out requiring  the  service  of  several  volumes. 
When  the  binder  is  filled  those  records  that 
are  not  in  current  use  for  reference  are  re- 
moved and  filed  in  special  cases. 

During  development  work,  the  faces  of  drifts, 
rises,  and  winzes  when  in  vein-matter  are  sam- 
pled daily,  taking  a  sample  weighing  from  25 
to  50  pounds.  A  numbered  tag  is  placed  in 
the  sample-sack,  which  is  then  sent  to  the  as- 
say-office. A  concise  description  of  the  sample 


458 


THE    MINING    MAGAZINE 


Table  I.— Montezum.a.  Vein,  No.  8  Tunnel,  Rise  No.  2. 


Date 

Number 

Description 

Width  Ft. 

Gold  Oz. 

Value  per  Ton 

Sept. 

1 

3 

8 

15 
130 

518 

2  ft.  above  tunnel  level  

1^                                                   

54 

50 

0-60 
124 
030 

$1200 
24  80 

n 

5-0 

600 

" 

Table  II. — Montezuma  No.  8  Tunnel,  No.  8  Stope. 


Date 

Number 

Description  of  Sample 

Width  Ft. 

Gold  Oz. 

Value  per  Ton 

Sept.      1 
„       14 
„       30 

1052 
1166 
1300 

7ft.  east  of  chute  No.  3J  17  ft.  up 

i    lift    west  of  raise  No    2     23   

8  5 
160 
11  0 

064 
026 

060 

$12-80 
520 

Over  chute  No.  31  36  ft.  up 

12  00 

Table  III. — Assays  of  Cak-Samples. 


Date 

Number 

• 

Chute  Number 

Cars 

GoldOz. 

Per  Ton  Value 

Sept.      5 

650 

1 

10 

048 

$9  60 

5 

651 

2 

16 

1-14 

22  80 

„        30 

962 

1 

6 

0  40 

800 

30 

962 

2 

17 

090 

1800 

„        30 

964 

3i 

10 

028 

5-60 

Table  IV. 


Chute  Number 

Tons 

Per  Ton  Value 

Gold  Value 

1 
2 
34 

6 
17 
10 

$8  00 

1800 

560 

$4800 

306  00 

56  00 

Total  for  the  day 

33 
1530 

— 

41000 

Previous  Total  

1442550 

Total  to  Date 

1563 
52-1 

949 

14835-50 

Averasje  

494  50 

Table  V.— Assays  of  Mill-Feed  Samples. 


Date 

Number 

Hours 

GoldOz. 

Per  Ton  Value 

Total 

Sept.         29 
30 

98 
105 

48 
88 

108 
074 

$21  60 
1480 

104640 
130240 

Total 

— 

132 
2031 

— • 

739 

234880 

Previous  Total. 

16079-96 

Total  to  Date... 
Average  to  Date 

— 

2163 
721 

— 

852 

18428-76 

DECEMBER,    191L 


459 


460 


THE    MINING    MAGAZINE 


isnotedon  the  stub  retained  in  the  sample-book 
andnumbered  to  correspond  with  the  tagplaced 
in  the  sack.  As  soon  as  the  sample-stubs  are 
turned  in  at  the  office,  usually  at  the  close  of 
the  day,  the  description  is  entered  in  the  assay- 
ledger,  with  date  and  number  of  the  sample, 
and  as  soon  as  the  assays  are  received  from 
the  laboratory  the  results  are  entered  in  the 
ledger  opposite  the  corresponding  number. 
Table  I  illustrates  this  clearly. 

In  addition  to  the  assay-record,  all  develop- 
ment samples  are  plotted  graphically  on  the 
assay-plan  and  shown  on  the  section  of  the 
Montezuma  No.  8  stope.  The  ordinate  is 
plotted  above  the  straight  line  representing  the 
roof  of  the  drift  on  a  scale  of  an  inch  to  the 
ounce,  and  at  the  point  where  the  sample  was 
taken.  In  this  way  the  mind  can  grasp  at 
once  the  relation  between  several  hundred  as- 
says, which  would  be  impossible  when  only 
reading  the  figures.  After  any  particular  piece 
of  development  work  has  been  completed  the 
assays  are  averaged  over  the  entire  distance, 
taking  into  account,  of  course,  the  width  of  the 
vein  where  the  samples  were  taken.  This  aver- 
age is  then  available  for  comparison  with  the 
car  and  stope  samples  from  the  same  place. 

Samples  are  taken  daily  as  the  stope  ad- 
vances, numbered,  and  recorded  in  the  same 
manner  as  the  development  samples  under  an 
appropriate  heading  as  shown  in  Table  II. 

Car-samples  are  also  taken  and  thrown  into 
a  box  numbered  to  correspond  with  the  chute 
from  which  the  ore  was  drawn,  at  the  scales 
where  the  ore  is  weighed  before  going  to 
the  mill.  These  samples  are  tagged  and  en- 
tered on  the  car-sample  sheet  as  shown  in 
Table  III. 

When  the  assays  of  the  car-samples  are 
received  from  the  laboratory  they  are  entered 
on  Table  III.  and  also  entered  in  another  re- 
cord on  which  the  total  gold  contents  is  com- 
puted as  shown  in  Table  IV. 

The  totals  are  carried  forward  daily  in 
order  to  indicate  the  average  of  the  ore  de- 
livered to  the  mill  for  the  month  up  to  any 
specified  date,  and  also  to  show  the  average 
at  the  end  of  the  month  without  it  being 
necessary  on  the  last  day  to  go  over  all  the 
records  and  make  all  of  the  computations  at 
one  time. 

Feed-samples  are  also  taken  at  the  stamps, 
which  crush  the  ore,  drawn  from  the  Monte- 
zuma No.  8  stope,  and  recorded  in  the  same 
manner  as  the  car-samples  from  the  mine,  and 
entered  as  shown  in  Table  V.  The  assay  is 
multiplied  by  the  battery-hours,  as  this  is  ap- 
proximately proportional  to  the  tonnage,  and 


the  total  so  obtained  at  the  end  of  the  month 
is  divided  by  the  number  of  battery-hours, 
giving  the  average  assay  of  the  feed  for  the 
month. 

It  is  seen  that  the  totals  can  be  carried  for- 
ward daily  for  these  samples  so  that  it  is  easy 
at  any  time  to  compare  the  mill-samples  with 
thecar-samples.  Atthe  beginning  of  the  month 
these  samples  might  be  considerably  far  apart, 
as  there  is  always  a  certain  amount  of  ore  left 
in  the  bin  from  the  previous  month,  but  this 
difference  largely  disappears  within  8  or  10 
days  and  by  the  end  of  the  month  the  two 
samples  should  check  within  reasonable  limits. 

In  the  examples  given  above,  actual  results 
are  quoted  as  obtained  for  the  month  of  Sep- 
tember. The  development  samples  for  50  ft.  of 
four  rises  and  150  ft.  along  the  level  of  Monte- 
zuma No.  8  stope  at  intervals  of  21  ft.  aver- 
aged $8'85  per  ton,  which  is  very  close  to  the 
average  of  the  mill-feed  samples.  The  stope- 
samples  averaged  $10'25,  but  these  are  not  so 
representative  of  the  average  grade  of  the  ore 
as  they  are  not  taken  at  uniform  distances  both 
vertically  and  horizontally,  but  are  useful  m 
noting  where  variations  occur  in  the  grade  of 
the  orebody.  The  car-samples  are  higher  in 
value  than  the  mill-samples,  on  account  of  the 
tendency  to  get  too  great  a  proportion  of  the 
fine  when  breaking  the  sample. 


Institute  of  Metals. —  The  next  half- 
yearly  meeting  of  this  Institute  will  be  held 
on  January  16  and  17.  William  Gowland, 
the  new  president,  will  deliver  an  address  on 
'  Copper  and  its  Alloys  in  Early  Times.' 
Among  other  papers  to  be  read  and  discussed 
are  the  following :  '  Properties  of  Certain 
Copper  Alloys  at  High  Temperatures,'  by 
Guy  D.  Bengough  ;  'The  Influence  of  Oxy- 
gen on  Copper  containing  Arsenic  or  Anti- 
mony,' by  R.  H.  Greaves  ;  '  Experiments  on 
a  Zinc-Antin^ony  Alloy,'  by  Carl  Benedicks; 
'  The  Nomenclature  of  Alloys,'  by  W.  Rosen- 
hain.  Mr.  Benedicks'  paper  'is  illustrated  in 
colour,  an  innovation  which  might  with  ad- 
vantage be  adopted  wherever  possible  in  con- 
nection with  the  portrayal  of  metallographic 
effects.  The  Institute  has  only  been  in  exist- 
ence for  three  years,  but  it  has  been  phenomen- 
ally successful  both  from  the  point  of  view  of 
the  quality  of  the  membership,  and  the  excel- 
lence of  the  papers  and  discussions.  During 
the  last  few  weeks  so  great  a  number  of  ap- 
plications for  membership  have  been  received 
that  special  councils  and  ballots  are  being  held 
so  as  to  complete  the  elections  before  the 
forthcoming  meeting. 


DECEMBER,   1911 


461 


PRECIS  OF  TECHNOLOGY 

Tin  in  German  Southwest  Africa. — The  South 
African  Mining  Journal  for  October  21  contains 
extracts  from  tlie  report  of  E.  Jorissen  on  the  geology 
of  a  new  tin  district  recently  discovered  near  the  line 
of  railway  between  Swakopmund  and  Windhoek, 
German  Southwest  Africa,  and  94  miles  from  the 
coast.  The  deposits  have  been  traced  over  a  tract  of 
country  measuring  six  square  miles,  in  an  undulating 
flat  round  the  southern  base  of  Erongo  mountain. 
This  mountain  is  a  boss  of  granite  intruded  through 
schist  and  quartzite.  The  schist  is  a  quartz-mica 
schist  containing  biotiie  with  some  muscovite,  and 
the  quartzite  only  differs  by  the  larger  amount  of 
quartz  grains  ;  in  some  places  the  two  merge  into  each 
other,  and  at  other  places  are  strongly  contrasted. 
The  strike  of  the  beds  averages  N  20"  E  and  the  dip 
40°  to  60°  south.  Numerous  dikes  of  felsite,  fine- 
grained granite,  and  granite-porphyry  cut  through 
the  strata,  and  they  can  be  generally  traced  to  the 
main  granite  intrusion.  Nearly  all  the  granite  dikes 
are  greisenized.  There  are  several  phases  of  intru- 
sion, the  principal  ones  being  (7)  the  main  intrusion 
with  which  are  associated  the  numerous  detached  in- 
trusions of  pegmatite  and  many  parallel  greisen  dikes  ; 
(2)  a  granite-porphyry  stage  in  which  the  later  dikes 
cut  through  the  previous  group  ;  (J)  greisen  dikes  cut- 
ting through  the  porphyry  ;  and  (4)  red  granite  dikes 
not  greisenized.  Each  stage  appears  to  be  connected 
with  tin,  but  the  lodes  in  the  neighbourhood  of  the 
porphyry  dikes  seem  to  be  the  most  promising.  The 
best  samples  have  come  from  coarse  white  pegmatite. 
The  lodes  are  notable  for  the  unusually  large  crystals 
of  cassiterite.  One  mass  of  cassiterite  is  said  to  have 
weighed  500  lb.  Dr.  Jorissen  does  not  commit  him- 
self to  a  definite  opinion  as  to  the  eventual  average 
ore,  as  the  workings  are  too  shallow  as  yet,  nor  have 
the  veins  been  followed  sufficiently  to  prove  con- 
tinuity, but  in  view  of  the  interest  caused  by  recent 
discoveries  in  Cape  Colony  near  the  Damaraland 
border,  and  the  development  work  done  by  the  De 
Beers  company  not  far  away,  his  report  is  of  import- 
ance. It  is  stated  that  the  property  is  to  be  floated 
immediately  at  Johannesburg. 

Diamonds  in  British  Columbia. — In  the  spring  of 
this  year  official  announcement  was  made  by  the 
Canadian  Geological  Survey  that  diamonds  had  been 
discovered  in  the  peridolite  of  the  Tulameen  district 
of  British  Columbia.  This  was  the  first  recorded  dis- 
covery of  diamonds  in  Canada  for  which  the  Survey 
can  vouch,  and  the  second  instance  of  their  being 
found  in  the  original  matrix  on  the  North  American 
continent,  the  other  being  in  Arkansas.  Fuller  details 
are  now  given  by  Charles  Camsell  in  the  September 
issue  of  Economic  Geology.  The  exact  locality  of 
the  discovery  was  on  Olivine  mountain  to  the  south 
of  the  Tulameen  river,  30  miles  from  the  United  States 
boundary,  and  100  miles  east  of  Vancouver.  For 
some  years,  placer  mining  has  been  conducted  in  the 
Tulameen  district,  but  no  diamonds  were  discovered 
in  the  gravels,  though  the  Survey,  knowing  of  the  ex- 
istence of  peridotite,  had  drawn  the  attention  of  the 
miners  to  the  possibility  of  diamonds  being  present. 
A  year  ago  the  officers  of  the  Survey  found  masses 
of  chromite  in  the  peridotite  and  sent  specimens  to 
R.  A.  A.  Johnston,  their  mineralogist,  for  examina- 
tion. In  the  course  of  his  analysis,  Mr.  Johnston  ob- 
tained a  residual  product  from  fusion,  that  proved  to 
be  diamonds.  Confirmatory  tests  were  made  subse- 
quently by  G.  F.  Kunz.  As  far  as  hae  yet  been  ascer- 
tained,  the  diamonds  are   associated   only   with    the 


chromite,  which  occurs  in  small  bodies  erratically 
distributed  in  the  peridotite.  The  diamonds  are  small 
but  some  are  of  excellent  quality.  They  are  difficult 
to  extract  from  the  rock  without  becoming  broken, 
and  even  after  extraction,  they  break  of  themselves, 
owing  to  inclusions  or  to  internal  strains  set  up  by 
release  from  surrounding  pressure.  The  largest  size 
so  far  found  is  not  greater  than  a  pin-head,  but  these 
split  on  exposure,  and  the  largest  that  was  permanent 
measured  only  03  mm.  It  will  be  seen  therefore  that 
the  discovery  is  of  geological  rather  than  of  commer- 
cial interest.  Mr.  Camsell  describes  at  length  the 
scientific  aspects  of  the   discovery. 

Ores  in  Sandstone  and  Shale. — In  Economic  Geo- 
logy for  September,  Waldemar  Lindgren  contributes 
a  paper  on  the  occurrences  in  various  parts  of  the 
world  of  ores  of  copper,  lead,  vanadium,  and  uranium 
in  sandstone  and  shale  far  away  from  igneous  rocks. 
These  ores  appear  to  have  a  common  mode  of  origin, 
and  he  discusses  their  probable  genesis.  The  ores 
are  usually  of  low  tenour,  and  in  the  majority  of  cases 
are  not  at  present  of  any  commercial  value.  The 
primary  ores  in  such  deposits  are  chalcocite  with 
small  amounts  of  bornite,  chalcopyrite,  and  pyrite  ; 
galena ;  roscoelite  (a  vanadium  mica)  ;  and  carnotite 
(vanadate  of  uranium).  Small  amounts  of  nickel, 
cobalt,  molybdenum,  barium,  and  selenium  com- 
pounds are  often  found.  In  some  deposits  all  these 
minerals  are  found  together,  but  usually  they  are  segre- 
grated  in  such  a  way  that  one  metal  predominates. 
Little  gangue  is  found  accompanying,  and  is  usually 
confined  to  calcite,  barite,  and  gypsum.  Where  the 
deposits  have  been  exposed  to  atmospheric  action,  the 
minerals  are  oxidized.  The  deposits  are  notably  con- 
fined to  formations  belonging  to  the  Permian,  Juras- 
sic, and  Trias,  and  characteristic  occurrences  are  con- 
nected with  fractured  or  brecciated  beds  or  where 
fossil  plants  abound.  More  rarely  the  ores  are  found 
in  fissures  in  the  same  formations,  where  they  were 
evidently  deposited  by  ascending  or  descending  atmos- 
pheric water.  Occasionally  the  ores  have  been  leached 
and  carried  downward  into  the  lower  strata.  The 
occurrences  of  copper  deposits  of  this  type  are  mainly 
on  the  flanks  of  older  continental  areas  containing 
pre-Cambrian  copper  deposits.  The  probability  is 
that  these  rocks  were  weathered  and  the  copper  ore 
contained  in  the  detritus  leached  by  atmospheric 
water  charged  with  salt  and  gypsum.  On  being  car- 
ried to  lower  horizons  the  solutions  would  be  concen- 
trated, and  the  copper  minerals  precipitated  by  re- 
actions with  coaly  vegetable  matter  or  by  the  cal- 
careous cement  in  the  sandstone.  Thus  the  deposits 
are  distinctly  epigenetic,  and  are  not  connected  with 
ascending  thermal  waters.  As  regards  the  vanadium 
deposits,  the  occurrences  are  somewhat  similar,  but 
the  association  with  carbonaceous  matter  is  even  more 
obvious.  Mr.  Lindgren  reviews  the  principal  deposits 
in  various  parts  of  the  world.  The  Russian  districts 
in  Perm  and  the  Southern  Urals  have  long  been  well 
known  for  this  class  of  copper  ore,  and  more  recently 
the  deposits  of  the  Akmolinsk  district  of  Southern 
Siberia  has  become  prominent.  He  also  gives  an  out- 
line of  the  known  occurrences  in  Germany  and  the 
United  States.  The  Katanga  deposits  is  mentioned, 
but  in  the  absence  of  information  the  author  is  not  in 
a  position  to  decide  whether  they  come  within  this 
category.  The  Mansfeld  cupriferous  shales  are  not 
included,  because  the  majority  of  geologists  consider 
the  copper  minerals  as  svngenetic  with  the  beds  them- 
selves. Mr.  Lindgren  also  reviews  the  occurrences 
of  vanadium  and  uranium  in  various  parts  of  the 
world. 


462 


THE     MINING     MAGAZINE 


The  Nissen  Stamp  in  South  Africa.— At  the  meet- 
ing of  the  Chemical,  Metallurgical,  and  Mining  Society 
of  South  Africa,  held  on  October  21,  P.  N.  Nissen 
read  a  paper  on  high-duty  gravity  stamp-mills.  Our 
readers  are  probably  aware  of  the  fact  that  the  Nissen 
stamp  has  been  tried  at  the  City  Deep  mill  in  competi- 
tion with  the  ordinary  heavy  stamp.  This  paper  gives 
the  results  of  these  tests,  and  also  a  general  disserta- 
tion as  to  the  advantages  claimed  for  the  author's  de- 
sign. The  Nissen  stamp  is  designed  on  the  principle 
of  '  one  stamp  one  mortar-box  '  ;  each  stamp  is  con- 
tained in  a  circular  mortar-box,  instead  of  five  side  by 
side  in  a  box  of  rectangular  section .  The  primary  object 
of  the  design  was  to  secure  a  more  rapid  discharge  of 
the  ore  directly  it  is  crushed  fine  enough  ;  but  it  also 
has  another  important  advantage,  more  recently  re- 
cognized, in  that  it  permits  of  the  expansion  of  the 
heavy-stamp  idea  without  involving  the  construction 
of  massive  foundations,  frames,  and  moving  parts.  As 
regards  the  discharge,  the  screen-area  can  be  made 


special  design.  In  the  design  of  the  heavy  5-stamp 
battery,  the  strains  set  up  limit  the  size  of  the  mortar- 
box,  so  that  if  the  weight  of  the  stamps  is  to  be  in- 
creased, this  cannot  be  done  by  increasing  the  diameter 
of  the  head,  shoe,  and  die,  but  only  by  increasing  the 
height  of  the  head.  Thus  the  centre  of  gravity  of  the 
falling  weight  is  unduly  raised,  and  the  distance  be- 
tween the  lower  guides  and  the  crushing  faces  is  made 
greater  than  it  should  be.  The  Nissen  stamp  has  a 
wider  and  shorter  head,  being  10  in.  diameter  for 
2000  lb.  weight,  and  owing  to  the  form  of  the  mortar- 
box  additional  weights  can  readily  be  fixed  on  the 
stem  .so  as  to  compensate  for  wear.  The  greater  width 
of  the  head  also  makes  it  possible  to  fit  the  shoe  and 
die  more  securely.  As  the  head  of  the  stamp  can  be 
made  in  such  substantial  form,  it  is  not  necessary  to 
have  a  long  stem  or  a  heavy  tappet.  Thus  the  height 
of  the  battery  can  be  reduced  and  its  stability  thereby 
increased.  The  increased  width  of  the  head  makes  it 
possible  to  have  a  wider  tappet  and  to  place  the  cams 


Test  Number  and  Date.  

No.  of  Stamps  and  kind 

Weight  of  Stamps,  lb 

No.  of  Drops  per  inin 

Height  of  Drop,  inches 

Height  of  Discharge,  inches 

Class  of  Screen 

Mesh  of  Screen 

Width  Aperture  in  inches 

Length  .\perture  ,,       

Dry  Ore  crushed,  tons 

Total  Run  in  hours  

Tons  per  stamp  per  24  hours 

H.P.  per  stamp*  

H.P.  hours  per  ton  of  ore  crushed* 
Lb.  ore  crushed  per  lb.  falling  weight 

per  day 

Ratio  water :  ore  by  weight 

Consumption  metal  in  shoes  in  lb.  per 

ton  crushed  


1 
June  23. 


4      lO.City 
Nissen  Deep 


1932 
103 
8h 
2i 
Tyler 
9 
0'205 
0'536 
180'86 
44'43 
24"47 
4'09 
4-0 

25'33 

5'4  :  1 


1863 
100 
8^ 
2i 
T.C. 
9 
0'205 
0'536 
19275 
25'33 
18'26 
4'21 
55 

196 
27  :  1 


2 
July  5. 


4       lO.City 
Nissen  Deep 


1927 
103 
8^ 
2 
Tyler 
9 
0'205 
0536 
180'25 
39'0 
2773 
4'09 
3"56 

2878 
4'2:  1 


0"129      0'145      0139 


1859 
100 
84 

2i 

T.C. 
9 

0'205 

0'536 

192' 12 

23"166 

19'90 

421 

5 '06 

2r412 
2"4  :  1 

0"24 


July  17. 


4 
July  26. 


Sept.  11. 


4       lO.City 
Nissen  Deep 


1855 
lOO 


2245 
103 
8|  8^ 

2  2i 

Sq.m.  14C08) 


§m. 
0375 
0"375 
193  88 
3170 
3669 
495 
3'24 

3268 
31  :  1 


gm. 
0"375 
0'375 
206'66 
2r83 
2272 
4'21 
445 

2449 
2'15:1 


4      10,  City 
Nissen  Deep 

2237 
103 
Si 

2         H 
T.T.C. 
9 
0"23 
0'85 
1917 
37'28 
30'85 
495 
3'86 


4       10,City 
Nissen  Deep 


•1993 
103 


1775 
100 


0198      0'187 


27'58 
3'2  :  1 

0"122 


o 
u 

o 
Z 


2k         2i 

Sq.  mesh  wire 

!  9 

I   0'277 

I   0'277 

185'32 

3729 

29'81 

4'23 

3'41 


29'91 
3'3  :  1 

0147 


9 
0'277 
0777 
19453 
2278 
20"95 
4'65 
5'32 

236 
33  :  1 


6               1 

Sept 

16. 

4      lO.City 
Nissen  Deep 

1991 

1773 

103         100 
8i         8^ 
2i          2i 
Sq.  mesh  wire 
iin.        Sin. 

0375 

0'375 

0'375 

0'375 

1857 

1917 

2952 

18'85 

3774 

24'34 

423 

465 

271 

456 

37'91 

27'45 

3'03:1 

376;1 

0'112 

008 

*  Excluding  Belt,  Shafting  and  Motor  losses. 
Grading  Analysis  in  Percentages. 


Feed 


Discharge 


+  2... 
+  14 
+h... 
+k... 

_i 

-f-60 
-t-90 
-90 
-200 


36'9 
18'6 

15'1 
11  7 
27'5 
65'2 
8'3 
97 
167 


12' 1 

14'4 

207 

127 

379 

63'4 

9'1 

12'0 

107 

14'96 
14'50 
20'40 
16'95 
3370 
64"9 
8'46 
8'46 
IS'IO 


12"4 
11"35 
19'35 
1770 
3970 
63'4 
870 
9'10 
19"5 


269 
1875 
19'3 
13'05 
22'0 
6774 
8'62 
10'84 
13'3 


187 
160 
18'15 
1675 
31'4 
6933 
9'09 
9'82 
1176 


52'3 

14"5 

10'4 

9'4 

13'4 

673 

875 

8'55 

15'4 


39'0 

197 

150 

93 

170 

666 

99 

8'8 

147 


141 

237 

27-1 

18'0 

20'9 

17"1 

2r3 

18'8 

19' 1 

160 

127 

12-6 

306 

23  "9 

241 

66' 5 

707 

707 

102 

10' 1 

103 

10'9 

107 

92 

12'4 

9"0 

9'8 

much  greater ;  the  pulp  at  each  fall  of  the  stamp  im- 
pinges at  right  angles  on  the  screen,  instead  of  follow- 
ing the  usual  whirling  path  ;  at  each  rise  of  the  stamp 
the  undischarged  pulp  is  drawn  to  the  centre  and 
therefore  into  a  position  which  will  give  the  greatest 
efficiency  to  the  next  blow.  The  feed  with  a  circular 
mortar  can  be  arranged  more  conveniently  for  ensur- 
ing the  delivery  of  the  ore  into  the  central  axis  of  the 
crushing  action  ;  this  fact,  together  with  the  suction 
of  the  rising  stamp  drawing  the  undischarged  pulp  to 
the  centre,  makes  a  more  even  distribution  of  the 
coarser  pieces  between  the  shoes  and  dies,  which  there- 
fore wear  more  regularly.  Coming  now  to  the  more 
advantageous  construction  of  the  various  parts,  it  is 
clear  that,  with  the  line  of  blow  being  always  in  the 
central  vertical  axis,  there  is  little  or  no  twisting  effect 
imparted  to  the  mortar,  as  is  the  case  where  5  stamps 
are  falling  in  such  an  order  as  to  obtain  a  whirling 
motion  to  the  pulp.  In  the  latter  case  the  mortar-box 
has  to  be  built  strong  to  withstand  the  strain,  the 
foundations  have  to  be  massive,  and  the  bolts  for 
fastening  the  box  to  the  foundations  ha\e  to  be  of 


nearer  the  cam-shaft  bearings.  The  illustration  shows 
the  form  in  which  the  stamp  has  been  adapted  for 
South  African  practice.  The  stamps  are  arranged  in 
couples,  and  two  couples  form  a  unit  for  driving.  The 
stem  is  5  in.  diam.  and  10  ft.  high,  and  the  centre  of 
the  cam-shaft  is  only  9^  ft.  above  the  top  of  the 
foundation.  According  to  this  construction,  the  power 
required  is  30%  less  and  the  weight  of  metal  required 
is  40%  less  per  ton  of  ore  crushed. 

The  accompanying  table  gives  the  results  of  the 
tests  at  City  Deep.  These  tests  were  made  by  the 
Central  Mining  and  Investment  Corporation  and  the 
report  is  signed  by  F.  L.  Bosqui,  consulting  metallur- 
gist, and  J.  H.  Rider,consulting  electrical  and  mechani- 
cal engineer.  The  Nissen  battery  consisted  of  4 
stamps  as  illustrated,  and  the  competing  mill  con- 
tained 10  stamps  of  the  standard  type.  It  will  be  seen 
that  the  power  consumed  per  ton  of  ore  varied  from 
27  to  4  hp.-hour  with  the  Nissen  stamp,  and  from 
445  to  55  hp.-hour  with  the  ordinary  stamp.  The 
ore  crushed  per  pound  of  falling  weight  varied  from 
25'35  to  37"91  lb.  with  the  Nissen  stamp,  and  from 


DECEMBER,    1911 


463 


464 


THE    MINING    MAGAZINE 


196  to  2745  lb.  with  the  ordinary  stamp.  By  Stadler's 
method  of  computation,  based  on  the  grading  analysis, 
the  relati\e  mechanical  efficiency  was  025  for  the 
Nissan  stamp  and  019  for  the  ordinary  stamp,  an  ad- 
vantage to  the  Nissen  by  35%. 

Marketing  Copper  in  the  United  States.  —  The 
Mining  and  Scientific  Press  for  October  28  prints  an 
article  on  the  methods  of  marketing  copper  produced 
or  refined  in  the  United  States.  The  United  Metals 
Selling  Co.,  that  used  to  be  the  great  Lewisohn  or- 
ganization, but  is  now  owned  by  the  Anaconda  and 
Amalgamated  Copper  interests,  is  still  the  largest 
dealer  in  copper  in  the  world,  but  the  Guggenheim 
organization,  the  American  Smelting  &  Refining  Co., 
is  running  it  close.  We  give  below  a  list  of  the  selling 
agents  with  the  estimated  amounts  that  each  will 
handle  in  1911. 
United  Metals  Selling  Co.  :  Pounds. 

Amalgamated 264,000,000 

Lake  mines 90,000,000 

Arizona  Copper 34,000,000 

Greene-Cananea    46, COO, 000 

Utah  Consolidated 8,000,000 

Pennsylvania  Salt 5,000,000 

Total 447,000,000 

American  Smelting  &  Refining  : 

Utah  Copper  100,000,000 

Nevada  Consolidated. 65,000,000 

Tennessee  Copper 14,000,000 

Ray  Consolidated  10, COO, 000 

Cerro  De  Pasco 48,000,000 

Tacoma  Custom  Smelter 100,000,000 

With  other  small  items  bring  Total  to  342,000,000 
Phelps,  Dodge  &  Co.  : 

Copper  Queen 112,000,000 

Detroit 23,000,000 

Calumet  &  Arizona 48,000,000 

Total 183,000,000 

American  Metal  Co.  : 

Old  Dominion 27,000,000 

Shannon  14,000,000 

Granby 10,000,000 

East  Butte  10,000,000 

Teziutlan 12,000,009 

Torreon 6,000,000 

Ducktown,  Fitzroy,  and  others 51,000,000 

Total 130,000,000 

L.  Vogelstein  (Aron  Hirsch  &  Sohn)  : 

United  States  S.  R.  &  M.  Co 24,000,0C0 

Orford 20.000,000 

United  Verde 40,000,000 

Smelter  products,  imports,  etc 46,000,000 

Total 130,000,000 

Charles  Raht : 

Calumet  &  Hecla  70,000,000 

Other  mines    8,000,000 

Total 78,000,000 


I. 


E.  P.  Earle 

Beer,  Sondheimer  &  Co.  |- Total 18,000,000 

W.  Parsons  Todd ' 

A  number  of  mines  sell  their  copper  direct  to  users, 
accounting  in  all  for  114,000,000  lb.  during  1911.  Of 
these,  a  number  of  Lake  Superior  mines  account  for 
48,000,000  lb.  It  is  of  interest  to  note  that  the  Miami 
proposes  to  market  its  metal  direct,  though  as  Adolf 
Lewisohn,  who  used  to  be  head  of  the  United  Metals 
Selhng  Co.,  will  be  in  charge  of  the  sales  department, 
the  distinction  between  the  two  methods  in  this  case 
is  not  marked. 


A  Strange  Mineral. — At  the  October  meeting  of 
the  Royal  Society  of  South  Africa,  B.  S.  J.  van  der 
Riet  read  a  paper  describing  the  curious  case  of  sup- 
posed discovery  of  a  new  mineral  at  the  Dutoitspan 
diamond  mine,  Kimberley.  The  incident  forms  an 
excellent  example  of  other  things  being  in  a  mine  be- 
sides the  particular  mineral  for  which  search  is  being 
made.  The  substance  was  found  in  the  pulsatorsand 
was  forwarded  to  mineralogical  experts  at  Cape  Town 
University  for  examination.  An  analysis  gave  iron 
71-3%,  silica  20-03%,  and  carbon  841%.  After  much 
inquiry,  the  suggestion  was  made  that  the  mineral 
closely  resembled  one  of  the  residuary  products  in 
the  manufacture  of  acetylene,  and  the  fact  that  this  gas 
is  made  on  the  spot  and  used  in  the  mine  helped  to  con- 
firm the  suspicion.  Comparison  was  then  made  with 
lumps  and  pellets  that  settled  in  the  lime  residue  from 
the  generators  used  at  the  chemical  laboratory  of  the 
University,  and  the  physical  characteristics  of  the  two 
were  found  to  be  similar,  as  to  hardness,  colour,  frac- 
ture, etc.  The  pieces  varied  in  composition  from  iron 
carbide  attacked  by  dilute  acids,  to  iron  silico-carbide 
attacked  by  hydrofiuoric  acid  but  not  by  hydrochloric 
or  sulphuric  acid.  The  discovery  of  the  material  in 
the  pulsators  had  at  first  been  hailed  as  a  petrological 
fact  that  might  help  in  the  elucidation  of  the  genesis 
of  diamonds,  and  the  real  cause  for  its  presence  was 
naturally  a  disappointment  to  the  scientists. 

The  Standard  Tin  Contract. — In  our  last  issue  we 
reproduced  a  table  giving  the  results  of  analyses  of 
well  known  brands  of  tin,  made  for  the  London  Metal 
Exchange.  We  are  informed  that  the  figure  for  tin 
content  in  Williams-Harvey  No.  4  is  incorrect;  the 
percentage  should  be  99941  instead  of  99'641  as  given. 
This  error  is  naturally  regrettable,  for  it  does  injustice 
to  the  smelters.  On  referring  the  matter  to  the  con- 
tributor of  the  precis,  we  find  that  he  made  the  mis- 
take of  using  the  reprint  of  the  table  that  appeared  in 
the  pages  of  The  Mining  Journal  instead  of  the 
official  circular. 

Cyaniding  Concentrate  at  Treadwell.  —  At  the 
meeting  of  the  American  Institute  of  Mining  Engi- 
neers held  in  October  at  San  Francisco,  W.  P.  Lass 
presented  an  elaborate  paper  on  the  new  cyanide  plant 
erected  for  the  purpose  of  treating  the  pyritic  concen- 
trate recovered  at  the  five  mills  of  the  Alaska  Tread- 
well  group  of  mines  These  mills  crush  in  the  aggre- 
gate about  5000  tons  per  day,  and  by  means  of  Frue 
vanners  about  90  tons  of  concentrate  is  obtained  per 
day.  The  gold  content  of  this  product  varies  from  2J 
to  4  oz.  per  ton.  The  average  may  betaken  at  rather 
over  3  oz.  The  gold  contained  in  it  represents  37% 
of  the  content  of  the  original  ore.  Until  recently  this 
concentrate  has  been  sold  to  the  Tacoma  smelter,  and 
the  companies  were  charged  ^11  95  for  freight  and 
treatment.  In  order  to  reduce  this  cost  it  was  decided 
three  years  ago  to  experiment  with  fine-grinding  and 
cyanidation.  Accordingly  a  small  plant  was  erected 
consisting  of  a  tube-mill,  amalgamating  plates,  Pac- 
huca  vat,  and  accessories.  It  was  found  that  75%  of 
the  gold  content  could  be  reco\'ered  by  amalgamating 
the  ore  during  and  after  reduction  to  minus  200,  and 
that  by  amalgamation  followed  by  cyaniding  a  total 
recovery  of  96%  could  be  effected.  It  was  figured 
that  with  a  plant  capable  of  handling  the  whole  pro- 
duct the  cost  would  be  ^3'25  per  ton,  and  this  added 
to  |2'48  representing  the  loss  of  4%  on  a  3%  gold  con- 
tent would  bring  the  total  cost  to  $573  per  ton.  Thus  a 
saving  of  |6'22  would  be  obtained  by  substituting  local 
treatment  for  shipment.  Subsequently  it  was  found 
that  the  same  extraction  could  be  obtained  by  cyani- 
ding direct  without  amalgamation.     However,  it  was 


DECEMBER,    1911 


465 


thought  best  when  building  the  full  plant  to  provide 
for  both  processes,  but  after  five  months  run  the  amal- 
gamation plates  were  discarded.  The  accompanying 
flow-sheet  shows  the  plates  in  place.  The  concentrate 
is  sluiced  direct  from  the  bins  to  Dorr  classifiers,  which 
feed  their  coarse  product  into  Abbe  tube-mills.   These 


4. 
5. 
6. 
7. 
8. 
9. 

10. 

11. 

12. 
13. 
14. 
15. 
16. 
17. 

IS. 
19. 
20. 
21. 

22. 


24. 


Baltloata  rnXnU 
Slag  to  smelter. 
Amalguo. 
Solatloo  retorned 
to  PACbQca  taokB. 
Talllaga  to  dim. 


Flow-Sheet  of  Tread  well  Cyanide  Plant. 


75-H.P.  Electric  Hoiit. 

Osgood  Track-Scales. 

Car-Tipples. 

Ore-Bins. 

Dorr  Classifiers. 

.Abbe  Tube-Mills. 

Classifiers. 

Launder  Distributors. 

Amalgam-Plates  for  coarse 
pulp. 

.A.ir-Lifts 

Dorr  Cl=^ssifier. 

.Abbe  Tube  Mill. 

-Air-Lift. 

Tank. 

Callow  Tanks. 

Launder  Distributors. 

.Amalgam-Plates  for  fine 
pulp. 

Distributor. 

Callow  Tanks. 

Callow  Tanks. 

Pierce  Amalgamators. 

Preliminary  .Agitation- 
Tanks. 

Aldrich  Electric  Triplex 
Pump. 

Pachuca  Agitation-Tanks. 


25. 

26. 
27. 

28. 
29. 

30. 
31. 
32. 
33. 
34. 

35. 
36. 

37. 


39. 

40. 
41. 
42. 
43. 

44. 
45. 


Byron  Jackson  4-in.   Cent. 

Pumps. 
Pulp-Tank. 
Wash-Water  Tank. 
Air-Lifts. 

Kelly  Filter-Presses. 
Distributor. 
Clarifyiny-Tank, 
Gold- Sumps. 
Wash-Waier  Sumps. 
.Aldrich     Electric      Triplex 

Pump. 
Alerrill  Zinc-Feeder. 
.Aldrich      Electric     Triplex 

Pump 
Merrill     Gold-Precipitation 

Presses. 
.Acid-Tanks. 

Drying-Furnace  for  Precipi- 
tate. 
Faber  du  Faur  Furnaces. 
.Amalgam-Barrel. 
.Amalgam-Press. 
Storage-Tanks    for    barren 

solution. 
Air-Lift. 
Air- Lift. 


mills  have  corrugated  sectional  liners,  and  3  in.  Danish 
pebbles  are  used.  When  amalgamation  is  employed 
the  overflow  from  the  classifiers  and  the  discharge 
from  the  tube-mills  is  passed  over  two  sets  of  plates 
for  treating  the  coar.se  and  fine  pulp  respectively,  in 
the  way  shown  in  the  flow-sheet.  The  pulp  from  the 
amalgamators  or,  if  these  are  omitted,  direct  from  the 
tube-mill  circuit  goes  to  Callow  cones,  the  spigot  dis- 
charge from  which  is  given  a  short  preliminary  cya- 
nide treatment  in  4  Pachuca  vats.  The  main  treat- 
ment is  effected  in  8  Pachuca  vats,  and  is  in  two  stages. 
In  the  first  treatment,  eight  hours  agitation  is  given 
with  01%  solution,  and  it  takes  18  hours  for  settle- 
ment and  decantation.  Afterward  a  second  treatment 
is  given  with  solution  drawn  from  the  wash-solution 
storage  tanks,  the  cyanide  strength  being  0  075%. 
This  agitation  lasts  for  2  hours,  and  the  solution  is 
then  decanted  and  used  as  solution  on  a  new  charge 
of  pulp  in  another  vat,  cyanide  being  added  at  the 
same  time.  The  pulp  after  the  second  agitation  goes 
to  Kelly  filter  presses,  and  after  extraction  of  the  solu- 
tion is  given  a  wash.  The  gold  solution  goes  to  Mer- 
rill precipitation  presses.  It  will  be  seen  that  the 
cyanide  solution  passes  from  the  end  to  the  beginning 
of  the  series  of  operations,  in  the  opposite  direction  to 
the  flow  of  ore.  A  two  months  run  from  May  16  to 
July  15  of  this  year,  after  amalgamation  had  been  dis- 
carded, gave  the  following  results  as  regards  cost  and 
e.xtraction  : 

Content  of  concentrate ^5549 

Content  of  tailing $189 

Tons  treated 4080 

Extraction 96'6% 

Cost  per  ton  : 

Labour 1124 

Power »025 

Pebbles  (13*  lb.) «0TS 

Cyanide  (2^ lb.) ^53 

Zinc-dust  (209  lb.) $017 

Other  chemicals  and  supplies $035 

Total $2  72 

Electrolytic  Assay  of  Gold  Solutions. — At  the  Sep- 
tember meeting  of  the  Chemical,  Metallurgical,  and 
Mining  Society  of  South  Africa,  Charles  Crightonread 
a  paper  describing  the  electrolytic  method  of  assaying 
gold  solutions  in  use  at  the  Kleinfontein  mine.  The 
apparatus  consists  of  four  oblong  frames,  measuring 
2  ft.  10  in.  by  3  ft.  6  in. ,  connected  in  parallel  and  each 
holding  eight  beakers.  Above  and  on  one  side  run  two 
copper  rods  connected  with  the  batteries  that  are  the 
source  of  current.  The  beakers  each  contain  anodes 
and  cathodes  connected  with  these  rods.  The  anodes 
consist  of  3^5  in.  arc-lamp  carbons  and  are  held  in  posi- 
tion by  clamps  fitted  to  the  copper  bar  above  the  beak- 
ers. The  cathodes  are  made  of  assay  lead-foil,  folded 
into  cylindrical  shape,  withserrationsat  the  lower  edge; 
these  are  connected  by  clamps  and  wires  to  the  copper 
rod  running  along  in  front  of  the  beakers.  The  cur- 
rent issupplied  by  three  2- volt  accumulatorcells,  which 
being  connected  in  series  give  a  terminal  pressure  of  6 
volts.  Theamountof  current  passing  through  the  solu- 
tion varies  directly  with  the  content  of  cyanide.  For 
instance,  a  solution  containing  0'3%  cyanide  passes 
01  ampere,  and  a  solution  containing  0  02%  cyanide 
will  take  0  04  ampere.  The  time  required  for  the  com- 
plete deposition  of  the  gold  is  4  hours,  after  which  the 
carbon  anodes  are  removed,  the  current  switched  off, 
and  the  lead  cathodes  disconnected  and  removed. 
When  dry,  the  cathodes  are  folded  into  small  compass 
and  cupelled  with  a  small  amount  of  silver.  The  whole 
time  occupied  in  the  process  in  5  hours.     Precaution 


466 


THE    MINING    MAGAZINE 


has  to  be  taken  that  the  carbon  anodes  are  not  left 
in  the  solution  while  no  current  is  passing,  otherwise 
some  of  the  gold  will  be  precipitated  on  the  anode.  If 
the  solution  should  offer  too  great  a  resistance  to 
the  current  it  is  well  to  add  a  small  amount  of  cya- 
nide so  as  to  increase  the  amount  of  current  passing 
and  accelerate  the  deposition.  This  method  has  the 
advantage  of  requiring  little  personal  attention,  but 
where  a  great  number  of  assays  have  to  be  made,  the 
time  occupied  is  against  it,  as  compared  with  the  usual 
precipitation  method. 


150  TCN  ORE  BIN 


Flow-Sheet  of  Hudson  Bay  Concentrator. 

Determining  the  Quality  of  Lime. — The  Bulletin 

of  the  American  Institute  of  Mining  Engineers  for  No- 
vember contains  a  paper  by  L.  W.  Bahney,  describing 
a  rapid  method  of  estimating  the  amount  of  calcium 
oxide  in  commercial  lime,  such  as  is  used  in  the  cyanide 
process  for  maintaining    protective    alkalinity.     The 


chemical  constitution  of  the  lime  supplied  for  this  pur- 
pose varies  widely,  according  to  the  quality  of  the 
limestone  used,  the  degree  of  efficiency  of  the  calcining 
operation,  and  the  conditions  under  which  it  is  stored. 
The  author's  method  requires  standard  solutions  of 
oxalic  acid  and  phenolphthalein.  The  acid  solution  is 
made  by  taking  14  6068  grammes  of  crystals  and  dis- 
solving it  in  sufficient  water  to  make  a  litre  of  solution, 
and  the  latter  is  made  by  dissolving  h  gramme  of 
phenolphthalein  in  50  cc.  alcohol  and  50  cc.  water. 
The  sample  is  ground  to  pass  200  mesh  ;  50  cc.  of 
water  is  placed  in  a  300-cc.  Erlenmayer  flask,  and  650 
milligrammes  of  the  sample  added.  After  vigorous 
shaking,  2  drops  of  phenolphthaleinsolution  are  added, 
and  then  the  o.xalic  acid  solution  added  until  the  pink 
colour  is  discharged.  Another  shaking  is  then  given. 
When  the  colour  returns  it  will  be  a  bright  vivid  pink 
if  due  to  lime,  and  the  addition  of  perhaps  0'5cc.  of 
solution  will  be  necessary  to  discharge  this  colour  ; 
but  if  the  flask  is  again  shaken  and  the  colour  is  a  faint, 
weak  pink  returning  slowly,  this  is  the  end-point  for 
the  lime,  and  indicates  that  the  magnesia  is  asserting 
itself.  At  all  times  during  the  addition  of  the  oxalic 
acid  solution  the  flask  should  be  violently  shaken,  so 
that  the  calcium  oxide  shall  pass  into  solution.  In 
nearly  every  instance  of  titration  of  a  high-grade  lime, 
the  pink  colour  remained  vivid  nearly  to  the  finish, 
which  shows  that  the  calcium  oxide  is  rapidly  soluble. 
If  a  complete  titration  is  allowed  to  stand  for  from  15 
to  30  minutes  the  pink  colour  will  return  and  show  as 
brightly  as  in  the  beginning.  The  reading  of  the  burette 
is  in  percentage  of  calcium  oxide. 

Concentration  at  Cobalt. — The  Canadian  Mining 
Journal  for  November  15  contains  a  description  of 
the  new  crushing  and  concentrating  plant  erected  by 
the  Hudson  Bay  Mining  Co.  at  the  northern  end  of 
the  Cobalt  district.  The  veins  are  in  conglomerate 
and  contain  niccolite,  smaltite,  aind  calcite,  while  the 
country  rock  for  a  foot  on  each  side  carries  leaf  silver. 
In  the  new  mill,  there  are  five  products,  namely,  1st 
and  2nd  class  hand-picked  ore,  and  jig,  sand,  and 
slime  concentrates.  The  capacity  of  the  mill  is  over 
2000  tons  per  month  ;  the  average  assay  of  the  mine 
ore  is  44  oz.  silver  and  of  the  tailing  J  to  ih  oz.  The 
ore  from  the  mine  after  passing  the  picking  table  goes 
to  crushers,  whereby  it  is  reduced  to  less  than  5  in. 
mesh,  and  then  to  three  sizing  screens,  which  separate 
it  into  four  sizes,  -f  iin.,  -fj  in.,  -1-^^  in.,  and  -^^  in. 
The  first  three  sizes  are  delivered  to  4  Harz  jigs  of  the 
double  compartment  type,  two  of  them  handling  the 
+  i  in.  material.  Any  native  silver  is  removed  from 
the  various  concentrates  before  they  go  to  the  ore- 
room.  Thehutchproducts  join  the  -  3^  in.  size  from 
the  screens  and  are  raised  to  a  hydraulic  classifier, 
which  removes  the  sand.  This  sand  is  treated  on  a 
James  table,  and  the  concentrate  therefrom  piped  to 
the  ore-room.  A  middling  is  returned  for  re-treatment. 
The  overflow  from  the  hydraulic  classifier  passes  to  a 
Callow  settler,  and  the  slime  is  treated  on  a  James 
slime-table.  The  tailing  from  the  jigs  and  tables  goes 
to  a  drag  dewaterer,  and  then  to  the  battery,  which 
contains  20  stamps  weighing  12501b.  each,  \vith  a  16 
mesh  screen.  The  pulp  from  the  stamps  goes  to  hy- 
draulic classifiers,  the  sand  being  treated  on  4  James 
tables,  the  middling  product  of  each  being  re-treated  on 
a  fifth  table  ;  and  the  slime  thickened  in  Callow  cones 
and  treated  on  4  James  slime  tables.  The  middling 
from  the  slime  tables  is  classified  and  the  two  products 
treated  on  two  other  tables.  The  total  extraction  of 
silver  by  all  these  processes  is  89%. 

The  Clancy  Process. — In  our  issue  of  January  last 
we  gave  a  long  abstract  of  a  paper  by  J.  C.  Clancy  de- 


DECEMBER,    1911 


467 


scribing  his  cyanide  process,  in  which  calcium  cyana- 
mide  is  used  as  the  source  of  cyanide.  In  Mining 
Science  for  November  9,  A.  W.  Warwick,  chief  metal- 
lurgist to  the  Moore  Filter  Co.,  which  owns  the  pro- 
cess, describes  the  new  plant  erected  at  the  Ajax  mine, 
Cripple  Creek,  for  the  purpose  of  treating  low-grade 
sulpho-telluride  ores  that  have  not  so  far  been  profit- 
able. Mr.  Warwick  prefaces  his  article  by  saying  that 
the  plural  is  necessary  for  describing  the  ores  of  this 
mine,  as  there  is  a  great  variety  of  them,  and  it  has 
proved  advantageous  to  keep  them  apart  when  treat- 
ing them  by  the  Clancy  process.  Readers  of  our  for- 
mer article  will  know  that  in  this  process  the  solution 
contains  calcium  cyanamide,  potassium  cyanide,  sul- 
pho-cyanide,  and  iodide,  and  that  the  solution  is  elec- 
trolysed with  the  object  of  obtaining  the  nascent  oxy- 
gen required  for  the  reaction.  The  sulphocvanideand 
iodide  are  not  lost,  and  the  solution  can  be  used  over 
again,  the  necessary  cyanide  being  obtained  by  the 
continual  addition  of  cyanamide.  During  the  experi- 
ments at  the  Ajax  plant,  the  important  discovery  was 
made  that  much  less  electric  current  can  be  used  than 
was  at  first  supposed,  and  thus  a  cost  that  might  have 
threatened  the  process  has  been  removed.  Here  a 
current  density  of  only  5  to  7  amperes  per  square  foot 
of  electrode  is  used,  instead  of  50  as  originally  figured. 
This  makes  a  great  difference,  and  during  a  24  hours 
agitation  the  energy  required  will  only  be  from  one- 
tenth  to  bne-seventh  of  a  kilowatt  per  ton  of  ore,  in- 
stead of  4J  kilowatts.  The  plant  has  a  capacity  of 
200  tons  per  day.  The  ore  is  crushed  in  rolls  and 
then  reduced  to  150  mesh  in  tube-mills,  the  solution 
being  introduced  in  the  latter.  Subsequently  the  pulp 
is  sent  to  agitators  having  a  capacity  of  80  to  100  tois 
dry,  the  ratio  of  ore  to  solution  being  1  :  1^.  In  each 
agitator  is  20  electrode-baskets,  each  having  an  anode 
surface  of  4  sq  ft.  and  a  capacity  of  35  amperes.  After 
agitation  the  pulp  goes  to  Moore  filters  and  the  solu- 
tion zinc-dust  precipitation-boxes.  The  movement  of 
the  pulp  is  effected  throughout  by  air-lift.  The  results 
obtained  at  this  plant  will  be  awaited  with  unusual  m- 
terest. 

CURRENT    LITERATURE. 

Prevention  of  Overwinding. — In  the  Colliery  Guar- 
dian for  November  3,  Henry  Briggs  describes  a  new 
apparatus  for  preventing  overwinding  in  mines,  at 
work  at  the  Dunnikier  Colliery,  Fifeshire,  invented  by 
the  manager,  J.  IVI.  Thomson. 

Mine  Air. — The  Journal  of  the  Franklin  Institute 
for  November  contains  a  lengthy  paper  by  E.  M. 
Chance,  chief  chemist  of  the  Philadelphia  &  Reading 
Coal  &  Iron  Co.,  describing  the  methods  of  estimating 
gases  in  tlie  air  of  coal  mines  and  the  symptoms  caused 
by  their  inhalation. 

Mine  Accidents. — At  the  November  jneeting  of  the 
Manchester  Geological  and  Mining  Society,  G.  B. 
Harrison  delivered  a  presidential  address  on  accidents 
due  to  falls  of  ground  in  coal  mines. 

Timber  used  in  Mining. — The  Canadian  Mining 
Journal  for  November  1  contains  an  article  by  H.  R. 
MacMillan  on  forestry  as  applied  to  the  use  of  timber 
for  mining  purposes  in  Canada. 

Flotation. — In  the  Engineering  and  Mining  Jour- 
nal for  November  18,  D.  P.  Mitchell  describes  the 
Elmore  and  Minerals  Separation  plants  at  the  works 
of  the  Zinc  Corporation,  Broken  Hill 

Slime  Filtration. — The  Bulletin  of  the  American 
Institute  of  Mining  Engineers  for  November  contains 
a  paper  by  George  J.  Young  detailing  a  great  variety 
of  experiments  in  connection  with  slime  filtration. 


Cost  of  Stamp-Mills. — The  Mining  and  Scientific 
Press  for  October  28  contains  an  article  on  the  cost 
of  erecting  and  constructing  a  stamp-mill  and  its  ac- 
cessories. 

Water  in  Mines. — In  the  Engineering  and  Mining 
Journal  forNovember  18,  Edmund  R.  Kirby  describes 
his  method  of  stopping  the  flow  of  water  in  mines  by 
injecting  mud,  sawdust,  or  other  obstructive  matter 
other  than  cement  into  the  crevices. 

The  Talisman  Mine. — The  Proceedings  of  the 
Australasian  Institute  of  Mining  Engineers  for  Sep- 
tember contains  a  paper  by  Arthur  Jarman  describing 
the  mine  and  metallurgical  plant  belonging  to  the 
Talisman  Consolidated,  in  New  Zealand. 

Great  Cobar. — Donald  Clark  commences  a  series  of 
articles  on  the  Great  Cobar  copper  mine  in  New  South 
Wales  in  the  Australian  Mining  Standard  for  Oc- 
tober 12 

Tungsten  and  Molybdenum  in  Queens'and. — The 
Queensland  Government  Mining  Journal  for  Octo- 
ber publishes  a  preliminary  report  by  Lionel  C.  Ball, 
assistant  government  geologist,  on  the  occurrences  of 
wolframite  and  molybdenite  in  Queensland. 

Valuation  of  Oil  Lands. — In  the  Mining  and  Scien- 
tific Press  for  November  4,  William  Forstner applies 
the  principles  laid  down  by  M.  H.  Burnham  in  his 
articles  '  The  Finance  of  a  Mine  '  to  the  valuation  of 
oil  lands. 

Gas-Power  at  Waihi. — The  Proceedings  of  the 
Australasian  Institute  of  Mining  Engineers  contains  a 
paper  by  S.  E.  Eraser  on  the  gas- power  plant  at  the 
Waikino  mill,  belonging  to  the  WaihiGold  Mining  Co. 

Kiinzel's  Gaseous  Fuel.  —  Mining  Science  for 
November  2  contains  an  article  on  a  gaseous  fuel  pre- 
pared from  oil  and  suitable  for  steam-raising,  smelting, 
etc.,  invented  by  C.  A.  Kiinzel  and  used  at  a  smelter 
at  Buena  Vista,  Colorado. 

Power  from  Sunshine.  The  Engineer  for  Novem- 
ber 10  describes  a  plant  invented  by  Frank  Shuman, 
of  Philadelphia,  for  producing  power  by  boiling  water 
by  means  of  the  sun's  rays.  This  plant  is  to  be  erected 
in  Egypt.  We  gave  our  opinions  on  the  economies  of 
concentrating  the  sun's  heat  in  our  issue  of  March 
1910 

British  Aluminium  Co.'s  Hydro-electric  Works. — 
At  the  meeting  of  the  Institution  of  Civil  Engineers 
held  in  November  two  papers  were  read  on  the  hydro- 
electric plant  of  the  British  Aluminium  Company  at 
Kinlochleven,  Scotland,  by  A.  H.  Roberts  and  F.  B. 
Sonnenschein  respectively. 

Bolivian  Railways. — The  Engineer  for  November  3 
contains  an  article  by  P.  F.  Martin  describing  the  new- 
railway  from  the  Pacific  to  Bolivia,  starting  at  .\rica 
on  the  Chile  coast  and  terminating  at  La  Paz.  It  is 
expected  that  the  railway  will  be  completed  early 
next  year.  The  line  is  267  miles  long,  the  greatest 
altitude  is  14,000  ft.,  and  28  miles  is  built  on  the  .\bt 
rack  system  where  the  gradient  is  6%. 

Prospecting  in  Brazil. — In  the  Mining  and  Scien- 
tific Press  for  November  4,  .Alexander  1'.  Rogers  de- 
scribes the  goldfields  on  the  eastern  side  of  the  .\ndes 
to  the  north  and  east  of  La  Paz  and  the  methods  of 
reaching  them  from  the  Amazon  river. 

Electrolytic  Assay. — At  the  September  meeting  of 
the  Chemical,  Metallurgical,  and  Mining  Society  of 
South  Africa,  C.  Crichton  read  a  paper  describing  the 
electrolytic  method  of  assaying  auriferous  cyanide  solu- 
tions, in  use  at  the  Kleinfontein. 

Copies  of  the  original  papers  and  articles  men- 
tioned under  '  Precis  of  Technology  '  and  '  Current 
Literature  '  can  be  supplied  on  application  to  The 
Mining  Magazine. 


6—6 


468 


THE    MINING    MAGAZINE 


BOOKS  REVIEWED 

A  Text-Book   of   Theodolite   Surveying   and 

Levelling.     Second    Edition.     By   James  Park. 

Cloth,    octavo,    320    pages,    illustrated.     London; 

Charles  Griffin  &  Co.     Price  7s.  6d      For  sale  by 

The  Mining  Magazine. 

The  author  is  one  of  the  best  known  writers  on  sub- 
jects connected  with  engineering,  geology,  mining,  and 
metallurgy.  He  has  the  gift  of  making  abstruse  prob- 
lems seem  quite  simple,  and  we  often  regret  that  his 
activity  is  centred  at  so  far  distant  a  place  as  the  Uni- 
versity of  Otago,  New  Zealand.  His  books  on  '  Min- 
ing Geology  '  and  the  '  Cyanide  Process  '  are  better 
known  in  this  country  than  his  treatise  on  '  Theodolite 
Surveying  and  Levelling.'  We  take  the  opportunity, 
therefore,  of  the  issue  of  this  second  edition  to  draw 
attention  to  it.  The  headings  of  the  variouschaptersare 
as  follow:  The  Theodolite  ;  Chains  and  Steel  Bands  ; 
Obstacles  to  Alignment  ;  Meridians  and  Bearings  ; 
The  Theodolite  Traverse  ;  Coordinates  of  a  Station  ; 
Calculation  of  Omitted  or  Connecting  Line  in  a  Tra- 
verse ;  Calculation  of  Areas  ;  Subdivision  of  Land  ; 
Triangulation  ;  Determination  of  True  Meridian,  Lati- 
tude, and  Time  ;  Levelling  ;  Railway  Curves  ;  Mine 
Surveying.  The  second  edition  contains  many  addi- 
tions and  revisions.  We  consider  that  Chapter  XH, 
relating  to  the  determination  of  the  true  meridian,  lati- 
tude, and  time,  and  occupying  nearly  one-third  of  the 
book,  is  of  great  value  to  the  mining  engineer  travelling 
or  working  in  distant  countries. 

Notes  on  the  Mineral  Deposits  of  the  Anglo- 
Egyptian  Sudan.    By  Stanley  C.  Dunn.    Pamph- 
let, 70  pages,  with  maps  and  illustrations        Khar- 
toum: The  Sudan  Press;  Edinburgh:  Oliver  &  Boyd. 
Price  Is.  6d.     For  sale  by  The  Mining  Magazine. 
This  is  the  first  of  a  series  of  Bulletins  issued  by  the 
Sudan  government,  a  scheme  undertaken  with  the  idea 
of  making  the  resources  of  the  Sudan  better  known. 
The  first  part  of  the  pamphlet  gives  a  general  idea  of 
the  geology  and  of  the  gold,  copper,  lead,  coal,  iron, 
and  other  known  deposits.      Following  this  is  a  his- 
torical account  of  ancient  gold  mining  operations.      A 
third  chapter  gives  extracts  from  Russegger's  '  Travels 
in  the  Sudan.'     Russegger  was  an  Austrian  bergrath 
who  was  sent  in   1835  to  the  Sudan  at  the  request  of 
the  Khedive  for  the  purpose  of  trying  to  help  the  local 
exchequer  by  discovering  gold  mines.    The  remaining 
half  of  the  book  contains  extracts  from  reports  made 
during  the  last   10  years,  by  mining  engineers,   who 
have  examined  various  tracts  of  the  country  for  Eng- 
lish prospecting  and  development  syndicates.     The 
book  is  one  of  distinct  and  permanent  value  to  those 
in  search  for  information  about  the  Sudan. 

The   Lay-out,    Design,   and    Construction   of 
Chemical  and   Metallurgical   Plants      By 
Oscar    Nagel.     Cloth,    octavo,    206   pages,    illus- 
trated.  New  York  :   The  Author.    Price  8s.  6d.    For 
sale  by  The  Mining  Magazine. 
This  book  gives  an  outline  of  the  plant  required  in 
connection  with  a  number  of  industries,  such  as  stamp- 
milling,  cyaniding,  silver  refining,  spelter  and  copper 
manufacture,  cement,  brick,  gas,  coke,  acid,  and  alkali 
works,  etc.     The  author  takes  one  example  of  each 
type  of  plant.     Practically  all  the  matter  has  already 
appeared   in   print,  either  in   technical   papers   or  in 
manufacturers'  circulars.   The  book  may  be  acceptable 
to  people  wanting  a  general  idea  of  the  plant  and  build- 
ings required  for  various  commercial  processes,  but  it 
seems  to  us  far  too  casual  and  sketchy  to  be  of  any 
great  technical  value. 


The  World's  Minerals.     By  Leonard  J.  Spencer. 

Cloth  octavo,  220  pages,  with  coloured  plates  and 

other  illustrations.     London  :   W.  &  R.  Chambers. 

Price  5s.     For  sale  by  The  Mining  Magazine. 

It  is  a  real  pleasure  to  read  this  book  and  to  write  a 
review  of  it.  Many  elementary  books  are  written  either 
by  semi-quacks  or  by  eminent  scientists  who  are  so 
steeped  in  learning  as  to  be  out  of  touch  with  the  re- 
quirements of  the  beginner,  and  they  therefore  do  not 
fulfil  their  object,  being  either  unreliable  or  involved. 
The  really  illuminating  and  readable  elementary  books 
are  few  and  far  between.  By  '  elementary  '  we  do  not 
mean  '  rudimentary,'  but '  explanatory  from  first  prin- 
ciples yet  containing  sufficient  information  to  satisfy  a 
trained  intellect.'  Mr.  Spencer's  book  exactly  meets 
this  definition  and  should  have  a  hearty  reception  from 
those  who  wish  to  obtain  a  general  idea  of  the  com- 
mon or  typical  minerals  and  of  the  main  principles  of 
mineralogy.  The  author  is  one  of  the  staff  of  the 
British  Museum,  and  is  editor  of  the  Mineralogical 
Magazine,  so  he  is  qualified  by  both  scientific  and 
literary  experience.  In  addition  he  gave  us  an  Eng- 
lish translation  of  Bauer's  great  work  on  precious 
stones,  now  unfortunately  out  of  print.  We  have  said 
that  the  present  book  gives  a  clear  outline  of  the  chief 
minerals,  but  of  course  it  cannot  teach  everything,  for 
without  the  minerals  themselves,  no  education  can  be 
complete.  His  40  coloured  plates  are  really  excellent, 
aud  it  is  marvellous  how  they  can  be  executed  at  the 
price  charged  for  the  book.  The  descriptions  of  the 
crystal  systems  and  the  method  of  making  models  out 
of  cardboard  are  clear  and  helpful.  Following  this 
section  are  classifications  of  minerals  according  to 
colour,  weight,  and  composition.  The  author's  classi- 
fication in  connection  with  the  last  named  follows  that 
of  the  British  Museum,  namely,  the  grouping  accord- 
ing to  combination  with  oxygen,  sulphur,  silica,  car- 
bonic acid,  the  halogens,  etc.  But  he  also  has  a 
secondary  classification  according  as  to  whether  the 
mineralsare  ores,  precious  stones, constituents  of  rocks, 
abrasives,  spars,  etc.  Then  follow  descriptions  of  116 
typical  simple  minerals.  The  book  is  brightly  written 
and  is  not  devoid  of  humour ;  the  author  quotes  the 
advertisement  of  the  American  dealer  in  mineral  speci- 
mens :  "  Minerals  for  presents  ;  send  your  friend  an 
apatite  for  his  Christmas  dinner."  In  conclusion  we 
may  say  that  the  book  is  one  that  we  shall  always 
recommend  to  those  in  search  of  the  practical  and  the 
beautiful.  E.W. 

Mines  of  Africa.  By  R.  R.  Mabson.  Cloth  oc- 
tavo, 900  pages,  with  many  maps  and  plans.  Lon- 
don :  The  Statist.  Price  21s.  For  sale  by  The 
Mining  Magazine. 

This  excellent  handbook  now  appears  every  year. 
Like  many  other  books  of  its  sort,  it  has  expanded  in 
bulk,  contents,  and  value  with  each  edition,  and  it 
now  includes  notices  of  the  mines  of  West  Africa  and 
Rhodesia  as  well  as  those  of  the  Transvaal.  The 
present  edition  includes  a  large  amount  of  new  ma- 
terial gathered  during  Mr.  Mabson's  visit  to  South 
Africa  during  the  early  part  of  this  year.  The  book 
gives  details  of  all  the  mining  companies  working  in 
Africa,  somewhat  after  the  manner  of  Skinner,  but  it 
deals  in  addition  with  the  technical  practice,  cost, 
production,  etc.,  which  make  it  much  more  interest- 
ing. The  plans  and  sections  of  various  mines,  and 
also  the  general  and  local  maps  are  useful.  We  have 
no  wish  to  be  hypercritical,  but  we  consider  it  would 
be  advantageous  to  separate  the  Rand,  other  Trans- 
vaal, Rhodesian,  and  West  African  mines  into  groups, 
instead  of  mixing  them  in  one  alphabetical  list. 


DECEMBER,  1911 


469 


COMPANY   REPORTS 

British  Broken  Hill. — It  is  pleasant  to  be  able  to 
record  that  a  great  change  of  fortune  has  come  to 
this  mine.  In  our  June  issue,  when  reviewing  the 
progress  during  the  second  half  of  1910,  we  stated 
that  the  company  had  not  been  one  of  the  most  suc- 
cessful on  the  Barrier  Range,  and  that  on  several 
occasions  the  mine  had  to  be  closed  during  periods  of 
low  prices.  From  December  1907  to  June  1910  the 
mine  was  idle,  but  during  that  time,  much  money  was 
spent  in  remodelling  the  lead  concentrator  and  in  pro- 
viding an  Elmore  zinc  plant,  so  as  to  enable  the  com- 
pany to  treat  the  ore  at  lower  cost,  and  obtain  a  better 
extraction.  The  mine  was  reopened  in  June  1910, 
and  the  new  plant  was  gradually  brought  to  a  state  of 
efficiency.  The  great  turn  in  the  fortunes  of  the  com- 
pany, however,  came  with  the  discovery,  in  June  last, 
of  a  new  lode  at  the  south  end  of  Block  16.  Our 
Melbourne  correspondent  has  already  recorded  the 
details  in  connection  with  the  development  of  this 
new  lode.  The  manager,  W.  H.  Woodhead,  an- 
nounced at  the  end  of  October  that  the  ore  reserve 
had  thereby  been  increased  by  two  million  tons.  The 
report  of  the  directors  now  issued  covers  the  half-year 
ended  June  30.  During  that  period,  63,370  tons  of 
ore  went  to  the  lead  concentration  plant,  averaging 
13'6%  lead,  128%  zinc,  and  7  6  oz.  silver,  and  9657 
tons  of  lead  concentrate  was  produced,  averaging 
63'4%  lead,  7%  zinc,  and  26  oz.  silver.  In  addition, 
34,845  tons  of  zinc  tailing,  averaging  15'3%  zinc, 
39%  lead,  and  39  oz.  silver,  was  produced  and  sent 
to  the  Elmore  plant,  which  produced  9621  tons  of 
zinc  concentrate,  averaging  43%  zinc,  10%  lead,  and 
12  oz.  silver.  The  income  from  the  sale  of  lead  con- 
centrate was /'68, 250  and  of  zinc  concentrate  £22JZ9. 
Other  credit  items  brought  the  revenue  to  ;^98,065,  of 
which  ;^15,142  was  net  profit.  Adding  the  balance 
from  the  previous  half-year,  the  amount  available  for 
distribution  was  /33,943.  Out  of  this  /26,400  has 
been  distributed  as  dividend,  being  at  the  rate  of  10% 
on  240,000  ordinary  shares  of  £\  each  and  25%  on 
60,000  privilege  shares  of  8s.  each.  Owing  to  the 
increase  in  ore  reserves  consequent  on  the  discovery 
of  the  new  lode,  it  has  been  possible,  since  the  close 
of  the  half-year  under  review,  to  work  three  shifts 
per  day  at  the  concentrator,  and  to  increase  the 
monthly  output  from  11,000  to  18,000  tons.  In  addi- 
tion to  the  zinc  tailing,  there  is  a  large  amount  of 
slime  that  cannot  be  efficiently  concentrated  by  the 
Elmore  process,  so  a  contract  has  been  made  for  the 
sale  of  the  accumulated  and  current  slime  at  8s.  6d. 
per  ton. 

Great  Fitzroy. — This  company  was  formed  in  the 
summer  of  1908  to  acquire  a  copper-gold  mine  near 
Rockhampton,  Queensland.  Bewick,  Moreing  &  Co. 
are  general  managers,  and  the  control  is  indicated  by 
the  names  on  the  list  of  directors,  Philip  Charley,  H. 
C.  Hoover,  G.  P.  Doolette,  W.  J.  Loring,  W.  S. 
Robinson,  and  J.  L.  Wharton.  The  results  obtained 
have  so  far  been  disappointing,  for  in  the  first  place 
water  concentration  was  a  failure,  and  secondly  the 
flotation  plant  has  not  yet  been  satisfactorily  adapted 
to  the  nature  of  the  ore.  The  report  now  issued  covers 
the  year  ended  June  30.  During  that  period,  69,791 
tons  of  ore  was  extracted,  and  59,128  tons,  averaging 
3^%  copper  and  3  dwt.  gold,  was  sent  direct  to  the 
smelter,  while  10,470  tons  averaging  24%  copper  and 
17  dwt.  gold  was  treated  in  the  Minerals  Separation 
flotation  plant.  This  plant  was  in  operation  for  4 
months,  during  which  time  the  recovery  was  81J%  of 
the  copper  and  47i%  of  the  gold.  With  the  low  current 


price  of  copper  and  the  poor  extraction  of  the  gold,  the 
concentration  was  not  a  success,  so  the  work  was  sus- 
pended and  experiments  started  with  a  view  to  increase 
the  efficiency.  Since  the  end  of  the  company's  finan- 
cial year,  operations  have  been  re-started,  the  scheme 
being  to  make  a  smelting  mixture  of  concentrate  ob- 
tained from  the  silicious  ore  and  of  selected  pyritic 
ore.  During  the  year  under  review,  782  tons  of  matte 
and  1268  tons  of  blister  copper  were  despatched  to  the 
Port  Kembia  refinery,  the  matte  being  shipped  during 
the  earlier  part  before  the  converter  plant  was  at  work. 
The  revenue  from  the  sale  of  the  metals  produced  was 
£U7,2S7,  and  the  working  expenses  ^138,464.  De- 
benture interest  and  general  expenses  brought  the  loss 
to  ;^9836.  In  addition,  it  has  been  necessary  to  write 
off  for  depreciation  of  plant  and  for  development,  and 
these  amounts  together  with  the  debit  balance  brought 
in  from  the  previous  year,  make  the  adverse  balance 
£57,700.  A  year  ago  we  recorded  that  /lOO.OOO  of 
debentures  had  been  created  for  the  purpose  of  pro- 
viding working  capital.  These  have  all  been  issued, 
and  in  addition  ;^20,000  has  been  borrowed  from  the 
Australian  Metal  Co.  The  general  managers  mention 
that  they  have  had  to  decrease  the  estimate  for  ore 
reserve,  because  the  flatness  of  the  pyritic  lode  involves 
the  leaving  of  a  large  proportion  of  the  ore  as  pillars. 
The  figures  at  June  30  were  :  pyritic  ore,  49,934  tons 
averaging  2^%  copper  and  2^  dwt.  gold  ;  silicious  ore, 
540,588  tons  averaging  3%  copper  and  2\  dwt.  gold. 

Gwalia  Consolidated. — This  company  was  origin- 
ally formed  in  1898  to  acquire  the  Star  of  Gwalia, 
adjoining  the  Sons  of  Gwalia,  in  Western  Australia, 
but  as  the  mine  was  unsuccessful  the  Violet  at  Lake 
Way  was  bought  in  1902,  and  the  adjoining  Lake  Way 
mine  in  1906.  As  recorded  in  our  issue  of  February 
last,  the  ore  at  the  Violet  has  proved  refractory  and 
much  of  it  is  of  low  grade.  The  managers,  Bewick, 
Moreing  &  Co. ,  and  the  consulting  engineers.  Hooper, 
Speak  &  Co.,  have  been  engaged  for  some  time  in 
studying  possible  processes  of  treatment,  so  far  with- 
out result.  The  report  now  published  covers  the  year 
ended  June  30,  and  shows  that  the  mill  was  closed  at 
the  end  of  July  1910,  and  the  mine  in  October.  The 
accounts  show  a  deficiency  on  the  year  of /10,712.  .\t 
the  meeting  of  shareholders  held  last  month,  Edward 
Hooper,  the  chairman,  gave  further  particulars  re- 
lating to  the  difficulty  of  treating  the  ore.  He  stated 
that  roasting  and  cyaniding  would  be  the  correct  pro- 
cess, but  the  price  of  fuel  for  roasting  is  prohibitive. 
An  alternative  proposition  involving  a  shorter  roast  has 
also  been  considered,  but  its  adoption  would  involve 
the  provision  of  dry-crushing  machines  and  pan-amal- 
gamators, and  the  directors  are  not  inclined  to  recom- 
mend so  large  a  capital  expenditure.  Many  other  pro- 
cesses have  also  been  tried  without  success.  Flotation 
gives  no  results.  At  the  present  time,  the  engineers 
are  examining  a  method  of  treatment  proposed  by  A. 
L.  Simon. 

Mount  Lyell. — The  report  of  this  copper  mine  in 
Tasmania  for  the  half-year  ended  September  30  shows 
that  100,957  tons  of  ore  was  raised  from  the  Mount 
Lyell  mine  and  59,738  tons  from  the  North  Lyell.  a 
total  of  160,965  tons,  averaging  27%  copper.  156oz. 
silver,  and  054  dwt.  gold.  On  smelting,  this  gave 
3841  tons  of  blister  copper,  containing  3797  tons  cop- 
per, 246,099  oz.  silver,  and  5018  oz.  gold.  The  pro- 
duce was  271  tons  of  blister  copper  less  than  during 
the  previous  half-year,  owing  partly  to  shortness  of 
labour  interfering  with  mining  operations,  and  partly 
to  some  of  the  stopes  yielding  poorer  ore.  Of  the 
copper  produced  during  the  period,  2532  tons  was 
sold  at  an  average  price  of  /57.  2s.  3d.  leaving  1265 


470 


THE    MINING    MAGAZINE 


tons  unsold  ;  the  balance,  1196  tons,  brought  forward 
from  the  previous  half-year,  was  sold  at  an  average 
price  of  £51.  16s.  lOd.  The  cost  of  producing  blister 
copper  was  20s.  Oid.  per  ton  of  ore,  being  an  increase 
of  2s.  4|d.  over  the  cost  during  the  previous  half-year, 
the  rise  being  due  to  the  smaller  tonnage,  the  greater 
amount  of  underground  stoping,  and  the  higher  cost 
of  coke.  The  last-named  disadvantage  has  since  been 
removed  by  the  starting  of  the  coke-ovens  at  Port 
Kembla.  The  reserves  on  September  were  :  At  Mount 
Lyell  open-cut,  360,975  tons  averaging  06%  copper, 
193  oz.  silver,  and  0'86  dwt.  gold,  and  underground, 
2,135,333  tons  averaging  052%  copper,  1  97  oz.  silver, 
and  0'5  dwt.  gold;  at  North  Lyell  1,023,362  tons 
averaging  6%  copper,  133  oz.  silver,  and  0  1  dwt. 
gold.  At  the  North  Lyell  the  developments  reveal  a 
continuance  of  the  orebody  in  depth.  The  profit  for 
the  half-year  was  lb9,QZ'i.  after  payment  of  taxes, 
/5098,  allowance  for  depreciation  /9468,  and  allo- 
cating ;fl0,392  to  the  exploration  and  development 
fund.  Owing  to  the  strike,  and  the  consequent  clos- 
ing of  the  mine,  since  the  end  of  the  half-year,  the 
directors  have  decided   to  pass  the  dividend. 

Lena  Goldfields. — The  properties  operated  by  this 
company  are  situated  in  the  valleys  adjoining  the  Vic- 
tim river,  a  tributary  of  the  Lena,  in  eastern  Siberia, 
and  consist  of  remarkably  rich  gold  gravel  deposits. 
They  are  worked  through  the  local  Russian  company, 
the  Lenskoie,  70%  of  the  shares  in  which  are  owned  by 
the  English  company.  The  report  now  issued  covers 
the  year  ended  September  30.  CM.  Rolker  reports 
that,  from  October  1910  to  October  1911,  the  produc- 
tion of  gold  was  430,818  oz.  worth  /1, 619, 331,  and 
that  the  average  content  per  cubic  yard  was  lOf  dwt. 
The  costs  of  mining  for  the  same  year  have  not  yet 
been  determined,  but  the  costs  during  the  previous 
year  were  /901,008  or  25s.  per  cubic  yard.  The  profit 
and  loss  account  of  the  English  company  showed  that 
the  receipts  from  dividends  on  Lenskoie  shares  for  the 
year  1909-10  were  /313,077,  and  that  the  interest  on 
money  lent  was  ;^28,716.  The  profit  was  /333,643, 
and  /336,664  has  been  distributed  as  dividend,  being 
at  the  rate  of  30%.  The  company  has  also  made  a 
profit  of  /^519,915  by  the  sale  of  shares  in  the  Lenskoie 
company  that  cost  originally  ;^68,820.  This  amount 
has  been  put  to  reserve,  and  thus  the  position  of  the 
company  has  been  immensely  strengthened,  without 
any  great  reduction  in  the  holding  in  Lenskoie  shares. 
As  regards  the  future,  the  reserve  of  gravel  is  estimated 
to  be  sufficient  for  3j  years'  work,  and  the  drilling 
operations  indicate  that  this  figure  will  be  substantially 
extended. 

Oriental  Consolidated. — This  is  an  American  com- 
pany, formed  in  1897  to  acquire  a  gold-mining  con- 
cession in  northwestern  Korea,  or  Cho-sen,  as  it  is 
nowadays  called.  H.  C.  Perkins  is  president,  and 
the  Ogden-Mills  and  Haggin  groups  have  large  hold- 
ings. The  principal  minesaretheTabowieand  Taracol, 
and  there  are  also  the  Chintui,  Kuk  San  Dong,  Chara- 
bowie,  and  Candlestick.  Five  mills  have  been  erected, 
containing  in  all  240  stamps,  together  with  concentra- 
tors and  cyanide  plants.  The  report  for  the  year  ended 
June  30  shows  that  342,956  tons  of  ore  was  mined 
(121,257  coming  from  the  Tabowie,  and  85,062  from 
the  Taracol),  and  that  the  yield  was  |1, 776, 470  or 
$5' 17  per  ton.  The  total  expense  was  |868,626,  leav- 
ing a  profit  of  $672,720  or  $196  per  ton.  The  dividends 
absorbed  $644,085.  This  company  is  the  pioneer  in 
Korea  and  the  methods  of  mining  and  extraction  are 
of  the  most  up-to-date  character.  The  recovery  was 
90J%.  The  developments  during  the  year  have  been 
satisfactory  on  the  whole.     The  Chintui  and  Kuk  San 


Dong    mines   are   approaching   exhaustion.     At    the 
Tabowie  the  lode  is  narrower  on  the  9th  level  than  it 
is  above,  and  the  content  is  not  much  greater.     The 
total  ore  reserves  were  estimated  on  June  30  at  802.280 
tons,  with  an  average  content  of  $480.     Alfred  Wel- 
haven  is  manager,  and  A.  E.  Drucker  is  metallurgist. 
Ouro  Preto  Gold  Mines  of  Brazil. — This  company 
was  formed  in  1884  to  acquire  the  Passagem  mine  in 
the  Stateof  Minas  Geraes,  Brazil.  John  Taylor  &  Sons 
are  the  managers,  and  A.  J.  Bensusan  issuperintendent. 
The  lode  has  a  flat  dip,  so  much  so  that  the  men  can 
walk  down  the  three  shafts,   which  commence  near 
each  other  at  the  surface,  and  become  farther  apart 
with  depth.     A  new  vertical  shaft  is  now  being  sunk  to 
meet  the  No.  3  shaft  at  a  point  a  little  Ic^wer  than  the 
680  metre  level.     It  will  be  remembered  that  in  our 
issue  of  November  1910  we  gave  a  summary  of  papers 
read  by  Mr.   Bensusan  and  by  R.  H.  Kendall  on  the 
mining    and  metallurgical   practice  at  this  mine   be- 
fore the  Institution  of  Mining  and  Metallurgy.  During 
the  year  ended  June  30,  69,680  tons  of  ore  was  mined 
and  milled,  yielding  gold  worth  /99,143,  being  at  the 
rate  of  28s.  5d.  per  ton.     These  figures  compare  with 
75,612  tons,  /108.773,  and  28s.  9d.  a  year  ago.     The 
fall  in  the  tonnage  was  due  to  a  temporary  scarcity  of 
workmen.   The  working  expenses,  including  royalty, 
were  ;^88,581,  other  income  was  /1643,  and  the  work- 
ing profit  was  ;i^l2,205.     Out  of  this  ;^5598  has  been 
written  off  lor  depreciation,  ;^3663  has  been  paid  as  pre- 
ference dividend  at  the  rate  of  10%,  and  £2500  on  the 
ordinary  shares  at  the  rate  of  2^%.     The  mine  con- 
tinues to  develop  satisfactorily.  On  June  30  the  reserve 
was  170,834  tons,  practically  the  same  figure  as  a  year 
ago.     In  addition,  there  are  large  bodies  of  ore  not 
sufficiently  developed  to  warrant  an  estimate.     In  last 
year's  report  it  was  mentioned  that  the  adjoining  Santa 
Anna  and  Macquine  properties  had  been  let  on  option. 
The  option  has  now  been  acquired  by  the  Brazilian 
Mining  Syndicate,  which,  under  the  guidance  of  John 
Taylor  &  Sons,  is  sinking  a  shaft  and  driving  a  cross- 
cut at  the  first-named  in  order  to  explore  the  deposit. 
Cape  Copper. — This  company  was  formed  in  1863 
to  work  the  Ookiep  copper   mine   in  Namaqualand, 
Cape  Colony.     John  Taylor  &  Sons  are  the  managers. 
The  high-grade  ore  is  shipped  to  Britonferry,  South 
Wales,  for  treatment,  as  is  also  the  matte  produced 
from  the  lower  grade  ore  that  comes  from  neighbouring 
properties.   For  some  time  the  mine  has  been  nearing  ex- 
haustion, but  it  still  continues  to  yield  a  limited  amount 
of  ore.     The  Nababeep  mine  yields  lower  grade  ore 
and  continues  to  develop  satisfactorily.  Ore  also  comes 
from  several  trial  mines.     The  company  has  an  interest 
in  the  Tilt  Cove  mines,  Newfoundland,  and  treats  the 
ore  at  Britonferry.     Options  are  held  on  properties  in 
Alaska  and  India.     The  report  for  the    year   ended 
August  30  shows  a  considerable  diminution  in  the  pro- 
fits as  compared  with  the  previous  year,  the  figure 
being  /60,862  as  compared  with  /124,659,  the  reduc- 
tion being  due  chiefly  to  the  lower  content  of  the  Ookiep 
ore.  During  the  year  15,978  tonsof  ore  was  raised  from 
the  Ookiep  mine  averaging  12%  copper,  as  compared 
with  15,196tonsaveraging  14'5%  the  year  before.  Atthe 
Nababeep  group  60,005  tons  averaging  5i%  was  raised, 
and  smaller  amounts  from  other  mines.     Prospecting 
by  bore-holes  has  been  adopted  at  the  various  mines. 
The  dividends  distributed  amounted  to  /37,500  on  the 
ordinary  shares  and  /5625  on  the  preference  shares, 
being  at  the  rate  of  6i%  in  each  case.     The  total  divi- 
dends to  date  have  been  /4, 499, 275.      In   May  last, 
J.  L.  Dean,  who  had  been  superintendent  at  the  Cape 
for  25  years,  resigned  ;  his  place  is  temporarily  held 
by  Ernest  R.  Woakes. 


DECEMBER,    1911 


471 


Tolima. — This  company  was  originally  formed  in 
1871  to  acquire  the  Frias  silver-lead  mine  in  Tolima, 
Colombia,  and  used  to  make  excellent  profits,  but  it 
had  to  be  reconstructed  in  1903  and  1909  with  the 
object  of  providing  further  funds.  The  report  now 
issued,  covering  the  year  ended  June  30,  shows  that 
the  mine  has  once  more  been  placed  on  a  profitable 
basis.  Ore  has  been  mined  on  various  levels  from 
1100  ft.  to  1600  ft.,  the  total  amount  raised  to  the 
surface  being  15,292  tons.  After  the  removal  of  about 
half  of  this  as  waste,  7763  tons  went  to  the  mill,  where 
1295  tons  of  shipping  concentrate  was  produced,  as- 
saying 472  oz.  silver  per  ton.  The  amount  receivable 
for  this,  after  allowing  for  smelter's  charges,  was 
;^60,452.  The  mining  profit  was  ;^15,561.  After 
payment  of j debenture  interest  and  London  adminis- 
tration expenses,   and    allowing   for   depreciation  of 

2'IV 


figures  compare  with  57,576  long  tons,  /98,669.  and 
34s.  3d.  during  the  preceding  year.  The  cost,  ac- 
cording to  the  working  account,  was  £73,173  or 
21s.  7d.  per  ton,  so  that  the  working  profit  was  /17,384 
or  5s.  Id.  per  ton.  The  monthly  statistics  show  wide 
variations  in  yield,  cost,  and  profit.  In  the  profit  and 
loss  account,  there  are  items  for  depreciation  /6626, 
debenture  interest  ;^4873,  London  charges /2416,  and 
a  number  of  other  items,  which  bring  the  working 
profit  down  to  a  net  profit  of  /2052.  The  ore  reserve 
has  been  increased  in  value,  but  not  in  tonnage  during 
the  year.  The  figures  on  December  31,  1910,  were 
397,759  tons  averaging  911  dwt.,  as  compared  with 
417,978  tons  averaging  858  dwt.  At  the  meeting  of 
shareholders  held  last  month,  it  was  announced  that 
the  slime  plant  was  completed  and  had  started  working. 
Ancobra  Exploration  &  Dredging. — This  company 


Ca^?e  Three  Points 

H         A  T  L  A   N  T  /  C  O  C 


20        JO        ^O        SO  MlL£S 


•  Railv^ays 


A  A/ 


WEST  AFRICAN   OOLDFIELDS. 


plant,  the  net  profit  was  /10,966,  which,  with  ^1678 
brought  forward ,  made  a  disposable  balance  of  /12 ,  644 . 
Out  of  this,  ;^3000  has  been  spent  on  additional  water 
rights,  ;^5500  has  been  devoted  to  the  redemption  of 
debentures,  and  £2500  has  been  distributed  as  divi- 
dend, being  at  the  rate  of  2j%.  The  outstanding 
debentures  amount  to  ;^9994.  The  report  states  that 
the  lode  at  the  deepest  level,  1620  ft.,  is  developing  in 
an  encouraging  way,  and  the  future  of  the  mine  ap- 
pears to  be  satisfactory.  Arthur  J.  Russell  is  man- 
aging director,  and  John  Russell  superintendent. 

Bibiani. — This  gold  mine  is  situated  in  West  Africa 
to  the  northwest  of  Prestea  and  Taquah,  and  owing  to 
its  distance  from  water  or  railway  communication  its 
development  has  been  hindered.  It  was  introduced  in 
London  in  1899,  and  the  company  was  twice  recon- 
structed, the  last  time  in  1908.  Hooper,  Speak  &  Co. 
are  the  consulting  engineers,  and  R.  J.  D.  Richardson 
is  manager.  The  report  now  issued  covers  the  year 
1910.  During  this  period  67,565  long  tons  of  ore  was 
raised  and  treated,  and  the  yield  by  amalgamation  and 
.cyanide  was  worth  ;^90, 557,  or26s.9d.  per  ton.    These 


was  formed  in  July  1909  to  acquire  from  the  Taquah 
Mining  &  Exploration  Co.  and  the  .\frican  Gold 
Dredging  &  Mining  Concession  certain  plant  and 
dredging  rights  in  West  Africa,  including  the  dredg- 
ing rights  on  the  .Ancobra  river  from  Prestea  to  the 
sea,  a  distance  of  70  miles.  The  control  is  with  the 
Oceana  Consolidated,  and  the  management  is  with  its 
subsidiary,  the  West  .\frican  Trust,  .\bout  a  year 
ago,  the  services  of  S.  J.  Weis,  a  California  dredging 
engineer,  were  secured.  The  report  now  issued  covers 
the  year  ended  June  30,  and  shows  that  the  four 
dredges  working  on  the  river  recovered  5120  oz.  gold 
worth  /21,747.  of  which  /2025  was  profit.  After 
close  study  of  the  conditions  and  former  operations, 
Mr.  Weis  is  of  opinion  that  it  w^ill  be  more  profitable 
to  work  the  gravel  that  forms  part  of  the  old  river 
bed,  instead  of  dredging  the  present  course.  In  order 
to  obtain  full  information  as  to  the  value  of  this  gravel, 
he  has  engaged  a  drilling  expert,  who  has  had  much 
experience  in  California,  to  thoroughly  test  the  flats. 
If  the  results  are  in  accordance  with  expectations,  a 
new  dredge  is  to  be  built  at  a  cost  of  /20,000.  and 


472 


THE    MINING    MAGAZINE 


the  necessary  funds  will  be  provided  by  the  issue  of 
additional  shares.  At  the  meeting  of  shareholders, 
the  chairman  announced  that,  since  the  close  of  the 
company's  financial  year,  one  of  the  dredges  has  been 
working  in  exceptionally  rich  ground. 

Sheba  Gold. — This  company  was  formed  in  1884 
for  the  purpose  of  acquiring  a  group  of  gold-mining 
properties  in  the  Barberton  district  of  the  Transvaal. 
Dividends  were  paid  from  1891  to  1898,  but  then  came 
a  series  of  disappointing  years,  and  it  is  only  during 
the  past  year  that  divisible  profits  have  once  more  been 
made.  The  control  is  with  Lewis  &  Marks,  G.  C.  Fox 
is  consulting  engineer,  and  H.  B.  White  has  recently 
succeeded  Howard  Hill  in  the  management.  The  re- 
port now  issued  covers  the  year  ended  June  30.  During 
this  period  49,455  tons  of  ore  was  raised,  chiefiy  from 
the  Zwarzkopje  mine,  and  24,016  oz.  of  gold  extracted 
by  amalgamation  and  cyaniding.  This  result  was  a 
great  improvement  over  the  previous  year,  when  40,750 
tons  yielded  14,120  oz.  The  revenue  from  the  sale  of 
gold  was  /95,903,  and  other  credit  items  brought  the 
total  income  to  ;^99,471.  The  net  profit  was  /20,573, 
out  of  which  ;^13,486  has  been  paid  as  dividend,  being 
at  the  rate  of  5%.  Since  the  close  of  the  financial 
year,  the  profits  have  continued  to  be  so  satisfactory 
as  to  warrant  the  distribution  of  another  5%.  The 
ore  reserves  have  been  substantially  increased  during 
the  year,  and  stood  at  104,250  tons  on  June  30,  as  com- 
pared with  24,000  tons  a  year  before,  and  the  grade 
is  estimated  to  be  equal  to,  if  not  greater  than,  that  of 
the  ore  treated  during  the  year.  At  the  beginning  of 
June  it  was  decided  to  reduce  the  capital  of  the  com- 
pany by  changing  the  denomination  of  the  shares  from 
/I  to  5s.,  and  the  capital  now  stands  at  /269, 738  in- 
stead of  /^l, 078, 954  as  formerly.  An  electric  installa- 
tion has  been  provided,  and  the  battery  is  being  driven 
by  motor  instead  of  by  steam.  The  prospects  of  the 
company  have  vastly  improved  since  we  wrote  our 
precis  of  the  directors'  report  a  year  ago. 

Nourse  Mines. — This  company  was  formed  in  1894 
as  the  Nourse  Deep  for  the  purpose  of  acquiring  the 
deep  levels  of  the  Henry  Nourse  mine  in  the  central 
part  of  the  Rand.  In  1905  the  Henry  Nourse  pro- 
perty was  absorbed  and  the  name  changed.  The  con- 
trol is  with  the  Wernher-Beit-Eckstein  group  and  it  is 
directed  by  the  Rand  Mines  Co.  R.  A.  Barry  is  man- 
ager in  succession  to  Percy  Cazalet,  and  B.  Madew  has 
recently  been  appointed  consulting  engineer  in  succes- 
sion to  G.  E.  Webber.  The  report  for  the  year  ended 
July  31  shows  that  operations  are  not  conducted  with- 
out difficulties,  and  that  the  recent  expansion  of  metal- 
lurgical plant  and  development  operations  have  not  so 
far  given  the  increased  profit  that  was  expected.  The 
full  plant  of  260  stamps  and  7  tube-mills  came  into 
operation  early  in  the  financial  year,  so  that  it  was 
possible  to  treat  643,675  tons,  or  179,098  tons  more 
than  during  the  previous  year.  The  average  grade  of 
the  mill-ore  was  73  dwt.  The  recovery  was  163,527  oz. 
by  amalgamation  and  60,044  oz.  by  cyanide,  a  total  of 
223,571  oz.  worth  ^936,597,  or  695  dwt.,  equal  to 
29s.  Id.,  per  ton  milled.  The  total  working  cost  was 
/695,572  or  21s.  7d.  per  ton,  leaving  a  profit  of 
^241,024  or  7s.  6d.  per  ton.  As  compared  with  last 
year,  the  total  profit  was  /49, 520  greater,  but  the  pro- 
fit per  ton  fell  by  9d.  This  reduction  was  due  to  a 
decrease  in  the  grade  of  the  mine  ore  by  J  dwt.,  but 
on  the  other  hand  closer  sorting  and  higher  percentage 
of  recovery  made  the  recovery  in  the  mill  only  ^dwt. 
less.  The  working  cost  shows  a  reduction  of  only  2d. 
per  ton,  which  is  naturally  a  disappointment.  The 
failure  to  effect  a  greater  reduction  is  due  to  a  com- 
bination of  causes,  the  chief  of  which  is  the  scattered 


nature  of  the  mine  workings  and  the  high  cost  of 
labour.  An  increased  amount  of  development  work 
has  been  done  during  the  year,  the  footage  being  28,549 
or  10,793  more  than  the  year  before  ;  the  tonnage  de- 
veloped thereby  was  750,198  tons,  of  which  614,171 
tons  was  estimated  to  contain  76  dwt.  gold.  On  the 
other  hand  it  has  been  necessary  to  write  down  the  ore 
reserve  by  raising  the  minimum  content  from  45  to  47 
dwt.,  so  the  reserve  on  July  31  stood  at  2,050,705 
tons  averaging  6'6dwt.,  a  reduction  of  91,342  tons  and 
an  increase  in  average  content  of  -^  dwt.  Nearly  li 
million  tons  of  ore  is  also  in  the  mine  averaging  3J  dwt. 
that  is  of  no  value  at  present.  The  circumstances  in 
connection  with  power  are  adverse,  for  the  electrifica- 
tion is  only  partly  completed,  and  both  steam  and  elec- 
tric plants  are  at  work .  The  prospects  of  the  company 
are  reported  as  fair  ;  it  is  necessary  that  the  full  scale 
of  operations  be  maintained,  and  that  working  costs 
be  reduced  by  a  concentration  of  underground  opera- 
tions. Of  the  profit  made  during  the  year,  ;^64,455  was 
allocated  to  capital  expenditure,  /^20,705  went  as  taxes, 
and  /165,564  was  distributed  as  dividend,  being  at  the 
rate  of  20%. 

Giant  Mines. — This  company  was  formed  in  1903 
to  acquire  from  the  Enterprise  Co.  the  Giant  gold 
mining  property  situated  65  miles  west  of  Salisbury, 
Rhodesia.  The  control  is  with  the  Weil  group,  and 
the  staff  of  the  Consolidated  Gold  Fields  of  South 
Africa  are  the  consulting  engineers,  H.  A.  Piper  being 
at  the  head.  Dividends  have  been  paid  regularly 
since  1906,  the  ore  reserve  has  been  steadily  increas- 
ing, and  additions  have  been  made  to  the  treatment 
plant,  until,  18  months  ago,  it  contained  30  stamps 
and  2  tube-mills.  The  report  now  issued  covers  the 
year  ended  June  30  last.  During  this  period,  123,789 
tons  of  ore  was  treated,  yielding  47,750  oz.  gold  worth 
;^202,196,  as  compared  with  65,953  tons,  24,089  oz., 
and  ^102,067  the  year  before.  The  percentage  of  re- 
covery was  85%.  The  extraction  per  ton  was  32s.  8d. 
as  compared  with  30s.  lid.,  and  the  cost  at  the  mine 
was  13s.  9d.  as  compared  with  17s.  6d.  The  working 
profit  was  /^l  16,884  as  compared  with  /44,316.  After 
London  expenses,  taxes,  and  depreciation  had  been 
allowed,  the  net  profit  was  /97,860.  Out  of  this 
/33, 080  has  been  placed  to  reserve  and  /49,360  dis- 
tributed as  dividend,  being  at  the  rate  of  20%.  The 
ore  reserve  on  June  30  was  308,146  tons  averaging 
41s.  6d.,  as  compared  with  307,821  tons  averaging 
38s.  3d.  the  year  before.  Mr.  Piper  reports  that  the 
exploratory  work,  under  the  direction  and  advice  of 
G.  S.  Corstorphine,  undertaken  with  the  object  of  re- 
covering the  faulted  lode,  has  not  yet  given  any  posi- 
tive results,  but  he  has  hopes  that  success  will  be  won 
eventually. 

Cam  &  Motor. — This  company  was  formed  in  Sep- 
tember 1910  by  the  London  &  Rhodesian  Mining  & 
Land  Co.,  which  is  in  the  control  of  Julius  Weil  &  Co., 
for  the  purpose  of  acquiring  the  Cam  &  Motor  gold 
mines,  situated  in  the  Gatooma  district  of  Rhodesia. 
Since  then  the  Good  Shepherd  mine  immediately  ad- 
joining the  Cam  mine  has  been  acquired  for  17,500 
shares,  and  the  issued  capital  increased  to  /467,500.  At 
the  flotation,  /200,000  was  provided  as  cash  working 
capital.  The  geological  formation  consists  of  crystal- 
line schists  traversed  by  dikes  of  various  characters. 
The  ore  is  found  in  connection  with  silicious  impregna- 
tions of  the  rocks  and  dikes,  and  arsenic  and  antimony 
are  associated  with  it.  At  the  time  of  fiotation  the  ore 
reserve  was  figured  at  302,000  tons  averaging  45s.  6d. 
The  report  now  issued  covers  the  period  from  the  time 
of  registration  of  the  company  to  June  30  last.  Work 
has  so  far  been  confined  to  the  development  of  the 


DECEMBER,    1911 


473 


Motor  mine,  and  to  the  study  of  the  methods  suitable 
for  the  beneficiation  of  theore.  The  latest  cable  advice, 
as  recorded  in  the  report,  showed  that  the  ore  reserve 
had  been  increased  to  700,000  tons  estimated  to  con- 
tain an  average  of  47s.  2d.  per  ton.  As  regards  treat- 
ment, it  has  been  decided  to  adopt  a  system  of  roast- 
ing and  all-sliming,  and  a  plant  with  a  capacity  of  600 
tons  per  month  is  being  erected  ;  theprocess  consists  of 
dry-crushing  in  a  ball-mill,  roasting  in  an  Edwards 
furnace,  and  sliming  in  cyanide  solution  in  a  wheeler 
pan.  If  this  experimental  plant  is  successful,  it  will 
be  expanded  to  a  capacity  of  500  tons  daily.  The 
laboratory  tests  indicate  a  recovery  of  85%. 

Messina. — This  company  was  formed  in  1905  to  ac- 
quire a  copper  mine  in  the  Northern  Transvaal  not  far 
from  the  Rhodesian  border.  A.  M.  Grenfell  is  chair- 
man, J.   M.   Calderwood  is  consulting  engineer,  and 


The  balance  of  working  profit  was  /2061,  but  in- 
terest on  debentures  and  insurance  premium  for  re- 
demption of  debentures  brought  the  balance  on  the 
wrong  side  to  the  extent  of  ;^5543.  In  order  to  con- 
tinue development  on  an  increased  scale  and  to  build 
additional  concentration  plant,  an  issue  of  /250,000 
debentures  has  been  made  since  the  completion  of  the 
year  under  review.  The  capital  of  the  company  now 
consistsof /165, 451  in  shares  and /304, 21  Odebentures, 
The  ore  reserves  blocked  out  on  June  30  amounted  to 
102,000  tons  averaging  10%,  and  the  probable  ore  to 
328,000  tons,  in  addition  to  which  there  is  a  large 
amount  of  possible  reserves.  The  assay  value  is  cal- 
culated over  a  width  of  5  ft.  The  minerals  are  chal- 
cocite,  bornite,  and  chalcopyrite,  and  no  indication  has 
yet  been  observed  of  any  change  in  the  nature  of  the 
deposit  with  depth.  The  new  shaft  has  been  completed 


J.  Allen  Woodburn  is  manager.  Though  the  deposit 
is  rich,  progress  has  been  hampered  by  the  want  of 
communication,  and  the  consequent  high  charges  for 
shipping  ore  and  concentrate  to  England.  The  policy 
has  been  to  confine  the  treatment  in  the  mill  to  ore 
raised  during  development.  The  disadvantage  as  re- 
gards transport  will  be  removed  before  long,  on  the 
completion  of  the  two  lines  of  railway  connecting 
Pretoria  and  Delagoa  Bay  respectively  with  the  Rho- 
desian railway  system.  The  Pretoria  railway  has  been 
completed  as  far  as  Bandolier  Kop,  which  is  93  miles 
from  Messina.  An  agreement  has  been  made  with  the 
Government  for  the  construction  of  aline  fromTzaneen 
on  the  Selati  railway  to  Bandolier  Kop,  thus  affording 
access  to  Delagoa  Bay,  the  nearest  port.  During  the 
year  ended  June  30  last,  17,286  tons  of  ore  was  raised 
averaging  11%  copper,  and  2503  tons  of  concentrate 
averaging  50'8%  produced.  The  amount  of  concen- 
trate shipped  was  2601  tons,  and  the  cost  of  freight 
was  over  ;^14,000,  while  the  sum  realized  was  /57,049. 


to  818  ft.,  and  development  is  being  prosecuted  in  the 
ground  thus  madeavailable.  The  directors  announce 
an  important  find  of  coal  15  miles  southwest  of  the 
mine,  and  the  company  has  secured  an  option  on  the 
property.  A  test  of  the  coal  at  the  mine  plant  gave 
satisfactory  results. 

Simmer  &  Jack. — This  is  the  leading  mine  of  the 
Consolidated  (lold  Fields  group  on  the  Rand.  The  re- 
port now  issued  covers  the  year  ended  June  30  and 
shows  that  890,200  tons  of  ore  was  hoisted  and,  after 
the  removal  of  waste,  811,448  tons  was  sent  to  the 
mill.  These  figures  are  slightly  lower  than  during 
the  previous  year,  owing  to  trouble  in  connection  with 
the  scarcity  of  labour.  By  amalgamation  in  the  batt.-ry 
37,669  oz.  of  gold  was  recovered  ;  during  the  first  part 
of  the  period  300  stamps  were  running,  and  after  the 
repairs  to  the  batterv  were  completed  in  February  the 
full  320  were  in  operation.  Below  the  6  tube-mills 
105,887  oz.  of  gold  was  recovered,  while  the  cyanide 
plant  yielded  75,734  oz.  from  the  sand  and  29,949  oz. 


474 


THE    MINING    MAGAZINE 


from  the  slime.  The  total  yield  of  gold  was  249,239  oz. 
worth  ;f  1,046,240,  being  at  the  rate  of  6'2dwt.  or  26s. 
per  ton  milled.  The  working  expenses  were  ;^501,414 
or  12s.  5d.  per  ton,  and  the  profit  /550,187  or  13s.  8d. 
per  ton.  After  the  payment  of  taxes  and  allowances 
for  depreciation,  the  balance  was  ;^526,866,  while 
/168,519  was  brought  forward  from  the  previous  year. 
The  dividend  absorbed  ;/;600,000,  being  at  the  rate  of 
20%.  The  ore  reserve  on  June  30  was  estimated  at 
2,520,000  milling  tons  averaging  64dwt.  per  ton,  and 
there  was  also  470,000  tons  of  partly  developed  ore 
estimated  to  contain  5'7  dwt.  The  ore  developed 
during  the  year  has  been  of  rather  higher  quality,  but 
the  amount  is  less,  as,  a  year  ago,  the  proved  reserve 
was  2,690,000  tons.  The  reports  by  C.  D.  Leslie,  con- 
sulting engineer,  and  A.  W.  Stockett,  manager,  show 
that  all  amalgamating  plates  have  been  removed  from 
the  stamps,  a  seventh  tube-mill  has  been  added,  and 
three  stationary  amalgamating  plates  provided  below 
each  tube-mill. 

Vogelstruis  Estates. — This  company  was  formed  in 
1893  to  acquire,  from  the  debenture  holders  of  the 
Vogelstruis  Gold  Mining  Co.,  an  outcrop  mine  on  the 
Rand,  seven  miles  west  of  Johannesburg.  A  mill  con- 
taining 80  stamps  started  in  1896,  but  did  not  run  for 
long,  as  it  was  found  necessary  to  do  more  develop- 
ment. Operations  were  resumed  in  1903.  Small  divi- 
dends were  paid  in  1907-8-9.  The  control  is  in  Lon- 
don, and  H.  RossSkinner  is  consulting  engineer.  The 
report  now  issued  covers  the  year  ended  June  30,  and 
shows  that  the  company  is  in  an  anxious  position.  It 
was  difficult  for  a  small  mine  with  an  isolated  control 
to  secure  labour  at  a  reasonable  rate,  and  it  was  there- 
fore found  necessary  to  curtail  development.  By  de- 
pleting theore  reserve,  an  average  of  60  of  the  SOstamps 
were  kept  at  work,  and  the  ore  crushed  amounted  to 
101,033  tons  yielding  gold  /132,669.  The  mining  ac- 
count shows  a  loss  of  /^999,  and  allowing  /8655  for 
depreciation,  and  charging  development  cost  on  the 
ore  reserve  sent  to  the  mill,  the  total  debit  for  the  year 
was  ;f  18,074.  There  are  /94,100  debentures  outstand- 
ing, and  it  has  been  necessary  to  suspend  the  annual 
drawings  for  their  redemption.  The  ore  reserve  on 
June  30  was  147,815  tons,  or  75,684  tons  less  than  the 
year  before.  Development  work  has  been  entirely 
suspended,  and  ore  is  being  mined  wherever  possible. 
This  policy  will  be  continued  as  long  as  debenture  in- 
terest and  administration  expenses  can  be  met 

Jumpers. — This  is  one  of  the  original  outcrop  mines 
of  the  central  Rand  and  has  escaped  absorption.  The 
ground  should  have  belonged  to  the  Geldenhuis,  but 
owing  to  inaccurate  surveys,  other  people  obtained 
possession.  Daring  recent  years,  the  control  has  been 
with  the  Wernher-Beit-Eckstein  group.  The  mine  is 
nearing  exhaustion  as  also  is  its  immediate  neighbour 
in  the  east,  the  Treasury  mine.  An  agreement  was 
made  in  October  last  to  work  the  two  mines  con- 
jointly, so  that  the  pillars  left  at  the  boundary  be- 
tween the  two  mines  might  be  made  available  for  ex- 
traction. The  report  now  issued  covers  the  year  ended 
July  31  last.  For  the  first  three  months  the  opera- 
tions were  confined  to  the  Jumpers  only  ;  from  Novem- 
ber 1,  1910,  to  July  31,  the  results  relate  to  the  con- 
joint working.  The  amount  of  ore  raised  from  the 
Jumpers  was  87,365  tons  and  from  the  Treasury 
48,353  tons,  a  total  of  135,718  tons.  The  actual 
amount  mined  was  188,399  tons,  the  difference  being 
due  to  careful  sorting  underground.  The  ore  raised 
was  further  sorted  on  the  surface,  and  120,802  tons 
sent  to  the  mill.  Thus  the  proportion  rejected  was 
36%.  An  average  of  95  stamps  were  at  work.  The 
extraction  by  amalgamation  was  33,402  oz.,  and  by 


cyaniding  20,127  oz.  a  total  of  53,529  oz.  or  886dwt. 
perton  milled.  Theincomewas/224,045  or  37s.  Id.  per 
ton  milled  and  the  working  cost  ;^180,180.  or  29s.  lOd. 
In  addition,  3203  oz.  was  recovered  from  accumulated 
slime,  and  737  oz.  from  the  treatment  of  dump  ore. 
It  has  been  possible  to  distribute  ;^40,000  as  dividend. 
The  output  during  the  past  year  was  not  so  great  as 
was  expected,  and  the  remaining  life  of  the  properties 
will  be  short.  The  reserve  is  estimated  at  122,314 
tons  of  profitable  ore,  and  108,000  tons  of  probable 
ore,  the  value  of  which  is  not  exactly  ascertained. 

Famatina  Development. — Thiscompany  was  formed 
in  1903  to  acquire  a  copper  mine  in  the  Argentine  Re- 
public, 14,000  ft  above  the  sea  in  the  Andes.  Pro- 
gress has  been  slow  owing  to  a  great  variety  of  causes, 
as  detailed  in  our  issue  of  November  last  year.  The 
report  for  the  vear  1910  shows  that  the  conditions  and 
circumstances  have  still  been  unfavourable.  The  smel- 
ter was  idle  from  the  early  part  of  the  year  until 
October,  owing  to  the  failure  of  the  Government 
aerial  ropeway  ;  during  this  time  a  second  furnace, 
a  briquetting  plant,  and  a  roaster  were  erected, 
and  development  was  continued  at  the  mine.  While 
the  smelter  was  at  work,  11,237  tons  of  ore  was  treated 
yielding  1383  tons  of  copper  matte  and  4^  tons  of 
blister  copper,  estimated  to  contain  392^  tons  copper, 
3976  oz.  gold,  and  72,221  oz.  silver.  The  value  of  the 
recovered  metals  was  /37,512,  but  the  total  expenses 
of  mining,  treatment,  and  administration  were/82,221, 
so  that  the  debit  balance  was  ;^44,709.  Durmg  the 
current  year  the  smelting  has  proceeded  with  fewer 
interruptions,  and  from  January  to  the  end  of  Octo- 
ber 933  tons  of  copper  matte  and  568  tons  of  blister 
copper  were  produced.  Since  April  the  whole  of  the 
output  has  been  in  the  form  of  blister  copper.  There 
have  been  serious  losses  in  copper  and  the  precious 
metals  owing  to  the  escape  of  dust  and  fume,  and 
flues  and  settling  chambers  are  to  be  provided.  The 
publication  of  the  report  has  been  delayed  because 
the  board  desired  that  one  of  their  number,  R.  F. 
Bury,  should  be  present  at  the  meeting  of  share- 
holders and  give  the  latest  news  ;  but  he  has  not 
been  able  to  return  from  the  mine  before  the  end  of 
the  current  year.  It  is  intended  to  hold  an  adjourned 
meeting  of  shareholders  early  in  the  coming  year, 
when  Mr.  Bury  will  present  his  report.  It  is  stated 
that  his  mission  has  been  successful,  as  he  has  been 
able  to  arrange  with  the  Government  for  more  settled 
transport  facilities  and  for  substantial  reductions  in 
the  freight  rates. 

Great  Cobar. — The  report  of  this  New  South  Wales 
copper  mine  covers  the  eighteen  months  ended  June 
30.  During  this  time  two  breaks  of  a  month  each 
were  made,  one  due  to  the  coal  strike,  and  the  other 
to  repairs  in  the  main  shaft.  The  operations  have 
been  hampered  by  labour  troubles,  and  the  costs ha\e 
increased  owing  to  the  rise  in  the  rate  of  wages.  Capi- 
tal has  been  spent  in  developing  the  Great  Cobar,  the 
Chesney  copper  mine,  and  the  Cobar  gold  mine,  and 
when  the  concentrator  is  at  work  at  the  Chesney  early 
next  year,  the  company  should  be  able  to  maintain  a 
regular  output  from  all  the  mines  and  to  produce  a 
suitable  smelting  mixture.  The  Cobar  gold  mine 
promises  to  be  an  exceedingly  useful  factor  in  the 
situation,  providing  a  silicious  mixture  for  the  pyritic 
ores  of  the  other  mines.  The  monthly  outputs  will 
be  26,000  tons  from  the  Great  Cobar,  13,000  from  the 
Chesney  (to  be  concentrated  to  5000  tons),  and  9000 
from  the  Cobar  gold  mine.  During  the  18  months 
under  review,  386,124  tons  of  ore  was  raised  from  the 
Great  Cobar,  46,137  tons  from  Chesney,  and  43,697 
tons  from   the  Cobar  gold,  a  total  of  475,988  tons. 


DECEMBER,    1911 


475 


The  smelter  treated  this  ore  and  also  some  of  the  ac- 
cumulated stock  and  purchased  material,  the  total 
amount  being  506,791  tons.  The  metals  dispatched 
from  the  smelter  were  9652  tons  copper,  36,649  oz. 
gold,  and  174,657  oz.  silver.  During  the  latter  6  months 
of  the  18,  the  assay  of  the  various  ores  were  ;  Great 
Cobar,  0  98  dwt.  gold,  0  429  oz.  silver,  and  2508% 
copper  ;  Chesney,  164  dwt.  gold,  0369  oz.  silver, 
and  3  287%  copper  ;  Cobar  gold,  0'5  oz.  gold,  0  5  oz. 
silver,  and  132%  copper.  On  June  30  last  the  re- 
serves were  :  Great  Cobar  2,142,000  tons,  Chesney 
602,000  tons,  and  Cobar  gold  344,000  tons.  The 
total  reserve  at  the  first  two  has  increased  by 
361,000  tons  during  the  18  months.  The  income 
during  the  period  was  ;^817,434,  and  the  gross 
profit  /102,354.  Out  of  this  ;fl3,000  has  been  al- 
lowed for  depreciation,  /22,886  has  been  devoted  to 

the    purchase    of    debentures,    and    

/66,492  has  been  paid  as  interest  on 
debentures.  In  October  1910  50,000 
new  shares  of  /5  each  were  created  ; 
of  these  15,000  were  issued  at  par  for 
cash,  and  20,000  were  issued  as  pur- 
chase price  for  the  Cobar  gold  mine, 
so  the  issued  capital  now  consists  of 
/925,000  in  shares,  and  there  is 
/732,152  in  debentures  and  deben- 
ture interest  outstanding.  H  C.  Bel- 
linger, the  general  manager,  contri- 
butes full  reports  on  the  mines  and 
smeltmg  plant.  Though  the  Great 
Cobar  has  given  shareholders  many 
disappointments  in  the  past,  the  pres- 
ent position  seems  to  be  satisfactory 
and  the  future  more   hopeful. 

Tomboy.  —  This    company    was 
floated    by    the   Exploration    Co.    in 
1899  to  acquire  the  gold  mine  of  that 
name  at  Telluride,  Colorado.     Four 
years  later  the  mine  showed  signs  of 
exhaustion, so  the  manager  at  the  time, 
John  Herron,  acquired,  on  his  own  re- 
sponsibility, on  behalf  of  the  company, 
the  lease   of   an  adjoining  property, 
the  Argentine.       This    property    re- 
deemed the  fortunes  of  the  company, 
and  the  directors  and  shareholders 
very  properly  granted  Mr.  Herron  an 
annuity  of  1%  of  the  net  yearly  profits,  on  his  retire- 
ment owing  to   ill-health  shortly   after.      .\t  first  the 
Argentine  group  yielded  handsome  profits,  but  during 
the  last  three  years  the  content  has  been  lower.     The 
report  now  published  covers  the  year  ended  June30  last, 
and  the  results  disclosed  are  almost  identical  with  those 
of  the  previous  two  years.     The  amount  of  ore  raised 
was  116,222  tons,   yielding  bullion    worth    ^462,773, 
and  concentrate  worth  $350,141,  the  total  value  being 
$781,324.     The  cost  was  $509,057,  so  that  the  mining 
profit  was  $272,267.     Profits  from  other  local  sources 
amounted  to  $37,108,  bringing  the  total  local  profit  to 
$309,375.     The  profit  in  English  money  was  /63,860  ; 
out  of  this  /5200  has  been  allowed  for  depreciation  of 
plant,   /4000  allocated  to  income  tax,  ;^546  paid  to 
John  Herron,    and  /^60,000  distributed  as   dividend, 
being  at  the  rate  20%.     The  present  manager,  David 
A.  Herron,  reports  the  ore  reserve  at  June  30  at  427,000 
tons,  as  compared  with  444,600  tons  a  year  ago,  and 
he  mentions  that  almost  all  the  stopes  have  continued 
to  disclose  profitable  ore.     It  is  granted  however  that 
the  resources  of  this  property  arelimited.   Animportant 
step  was  taken  since  the  conclusion  of  the  year  under 
review,  in  July  last,  when  the  southern  portion  of  the 


Revenue  Tunnel  company's  property  was  acquired 
for  ;,r80,000  This  piece  of  ground  haS' only  been  in- 
termittently worked  by  the  Revenue  Co.,  owing  to  the 
natural  disadvantage  of  its  being  on  the  other  side  of 
the  divide  to  the  main  portion.  Its  position  is  favour- 
able to  its  exploitation  by  the  Tomboy  Co.  At  the 
present  time  a  line  is  being  built  to'  facilitate  the 
transport  of  the  ore  to  the  Tomboy  mill.  We  pub- 
lish herewith  a  map  of  the  district  showing  the  relative 
position  of  these  properties  and  of  the  Camp  Bird. 

Stratton's  Independence.— This  gold  mine  at  Cripple 
Creek  is  too  well  known  for  it  to  be  necessary  for  us 
to  recapitulate  here.  After  a  successful  life  as  a  gold 
producer,  the  mine  was  let  to  tributers,  and  the  com- 
pany's own  operations  confined  to  the  treatment  of 
low-grade  dumps.  Particulars  of  the  method  of  treat- 
ment were  given  in  our  last  issue  by  Philip  Argall,  the 


ScALa  of  Af/c£s 


Part  of  Colorado,  showing  Toviboy  and  Revenue  Tunnel  Properties. 

present  manager.  In  1908  the  capital  was  written  down 
by  87%,  and  now  stands  at  7^125,000  in  a  million  shares 
of  2s.  6d.  each.  The  report  now  issued  covers  the  year 
ended  June  30.  It  shows  that  the  concentrating  and 
cyanide  plant  treating  the  dump  ore  has  been  brought 
up  to  10,000  tons  per  month,  and  that  the  tonnage 
treated  during  the  year  was  109,800,  as  compared  with 
68,711  the  year  before.  The  production  was  12,361  oz., 
which  sold  for  ^45, 788,  after  deducting  transport  and 
smelter  charges  ;  the  cost  of  treatment  on  the  spot  was 
/33,173,  and  the  profit  /12,614.  The  recovery  was 
71^%  of  the  estimated  contents.  In  addition  to  this  ex- 
traction by  concentration  andcyanidation  of  dump  ore, 
2752  tons  of  ore  was  raised  from  the  mine  by  the  com- 
pany, bringing  a  net  revenue  of  ;^5S1 2,  and  15,633  tons 
was  raised  by  tributers,  thecompany'sshareof  the  pro- 
fit being /'28,813.  After  paying  for  administration  and 
London  expenses,  the  balance  available  for  distribution 
was  /21,006.  Out  of  this  ;f  12,500  has  been  distributed 
as  dividend,  and  another  dividend  at  the  same  rate 
has  since  been  declared  out  of  the  profits  of  the  current 
year.  It  is  of  interest  to  note  that  the  caved  part  of 
the  mine  has  been  reopened  by  the  company,  and  that 
some  high  grade  veins  have  already  been  disclosed. 


476 


THE    MINING    MAGAZINE 


Uruguay  Consolidated. — This  company  was  formed 
in  the  summer  of  1909  to  acquire  the  San  Gregorio  gold 
mine  at  Corrales,  in  the  State  of  Riveria,  Uruguay. 
St.  John  Winne  is  chairman  and  W.  H.  Argall  is  on 
the  board.  Frank  Holmes  is  manager.  The  report 
now  issued  covers  the  half-year  ended  March  30  last. 
Up  to  that  time  work  had  been  confined  to  prospecting 
and  development,  to  overhauling  the  60-stamp  mill 
acquired  from  the  former  owners,  and  to  the  provision 
of  additional  metallurgical  plant.  The  capacity  is  now 
70,000  tons  per  annum,  but  further  power-generating 
plant  will  be  required.  Since  the  end  of  the  period 
covered  by  the  report,  J.  G.  Ralph  has  visited  the 
mine,  and  he  and  the  manager  have  reported  the  exist- 
ence of  large  orebodies,  of  unusual  width,  and  of  com- 
paratively low  grade.  The  proved  ore  on  March  31 
was  given  by  Mr.  Holmes  at  134,838  tons  averaging 
3j  dwt.  or  14s.  6d.  per  ton,  which  can  be  worked  at  a 
cost  of  9s.  per  ton.  The  directors  are  now  asking  for 
/50,000  additional  capital  for  the  purpose  of  retiring 
the  debentures  and  loans,  and  for  continuing  the  de- 
velopment of  the  mine  and  improvement  of  the  plant. 

Tetxco  Mines  of  Mexico.  —  This  company  was 
formed  in  April  1910  to  acquire  the  old  Rosario  silver 
mine  in  the  State  of  Guerrero,  Mexico.  This  mine 
was  worked  previously,  but  abandoned  when  the 
oxidized  ore  was  exhausted,  as  the  sulphide  was  not 
rich  enough  for  shipping  to  the  smelters.  T.  R 
Marshall  reported  that  the  sulphide  is  amenable  to 
the  modern  method  of  fine  grinding  and  cyanidation. 
The  first  annual  report  now  issued  shows  that  suffi- 
cient development  work  has  been  done  to  warrant  the 
erection  of  a  100  ton  cyanide  plant.  The  ore  varies 
greatly,  but  Mr.  Marshall  is  of  opinion  that  a  con- 
stant average  of  20  oz.  ore  can  be  obtained  for  the 
proposed  plant.  He  estimates  that  the  net  profit 
should  be  not  less  than  £\  per  ton.  The  directors  are 
now  increasing  the  capital  from  /G0,000  to  ^100,000 
in  order  to  provide  the  necessary  plant  and  to  con- 
tinue development. 

TRADE    NOTES 

Most  of  the  trade  publications  mentioned  in  this 
column  are  available  for  distribution  and  the 
tnanager  of  The  Mining  Magazine  will  be 
pleased  to  secure  copies  for  persons  interested. 

The  British  Humboldt  Engineering  Co.,  Ltd.,  report 
three  orders  for  their  Magnetic  Laboratory-Type  Sepa- 
rators, for  treatment  of  tin,  wolfram  and  similar  ores. 

John  Russell  &  Co.,  Ltd.,  send  us  their  catalogue 
of  138  pages  giving  useful  information  on  tubes  and 
fittings.     It  contains  17  pages  of  conversion  tables. 

Head,  Wrightson  &  Co.,  Ltd.,  have  published  a 
catalogue  describing  the  Hendryx  Agitator.  A  testing 
plant  has  been  equipped  in  London  for  testing  ore 
with   this  process. 

The  Ingersoll  Rand  Co.  now  control  the  business  of 
the  J.  Geo.  Leyner  Engineering  Works  at  Littleton, 
Colorado.  This  new  move  marks  additional  progress 
on  the  part  of  this  well  known  firm. 

The  Kilbourne  &  Jacobs  Manufacturing  Co.  have 
sent  us  for  our  files  a  complete  set  of  their  catalogues 
describing  mine  cars  and  trucks.  They  are  represented 
in  London  by  L.  B.  Chandler,  Broad  Street  House, 
E.G. 

The  New  York  Engineering  Co.  are  distributing  a 
new  catalogue  describing  TheEmpireTailing  Elevator. 
This  machine  is  intended  to  overcome  the  difficulty  of 
working  placer  ground  which  will  not  warrant  an  ex- 
tensive dredging  plant,  and  where  the  contour  of  the 
country  does  not  provide  sufficient  grade  for  sluicing. 


Edward  M.  McIIvain,  formerly  president  of  the 
Bethlehem  Steel  Co.  and  latterly  president  of  the 
Universal  Vanadium  Company,  has  resigned  the  latter, 
to  accept  the  Presidency  of  the  Lehigh  Coke  Company, 
which  company  is  constructing  a  by-product  coke  oven 
plant  at  South  Bethlehem,  Pa.  The  New  York  office 
of  the  company  is  at  No.  71  Broadway. 

Jens  Orten-Boving  &  Co.  have  made  a  special  study 
of  pumping  and  water-power  plants,  and  are  distribu- 
ting to  those  interested  a  bulletin  dealing  more  par- 
ticularly with  their  Victoria  Turbo  Pump  which 
has  been  installed  in  a  number  of  places  with  great 
success.  One  of  these  pumps  at  the  Lambton  Collieries 
is  working  against  a  head  of  315  feet  and  discharging 
2900  gallons  per  minute  and  shows  an  efficiency  of  86% . 
The  Bucyrus  Company  have  increased  their  capital 
stock  to  910,000,000  with  $8,000,000  issued.  New 
shops  are  being  erected  at  Evansville,  Indiana,  in  ad- 
dition to  the  present  works  at  South  Milwaukee.  It  is 
the  purpose  of  the  company  to  expand  their  scope  of 
business  in  all  types  of  bucket,  dipper,  and  hydraulic 
dredges,  and  steam  and  electric  shovels,  for  which 
they  have  established  an  enviable  reputation. 

The  Worthington  Pump  Co.  have  sent  us  an  im- 
posing list  of  their  recent  sales.  It  is  interesting,  not 
only  on  account  of  the  gratifying  number,  but  be- 
cause of  the  varied  purposes  and  industries  for  which 
their  products  are  adapted.  The  sales  include  many 
different  types  of  pumps  :  triple  expansion,  plunger, 
electrically  driven,  fire,  high  and  low  lift  centrifugal, 
vacuum,  etc.,  also  surface  and  jet  condensers,  water 
meters  and  air  compressors. 

Hadfield's  Steel  Foundry  Co.  have  issued  catalogue 
No.  102  (9  by  11  in.,  24  pages  and  cover)  to  describe 
the  Symons  Disc  Crusher.  This  catalogue  should 
prove  of  interest  to  e\'ery  engineer  interested  in  reduc- 
ing stone  or  ore.  The  principles  of  crushing  have 
undergone  decided  changes  in  the  past  few  years,  and 
this  device  appears  to  have  particular  merit.  The  ex- 
cellent illustration  and  reading  matter  seem  to  have 
been  put  together  with  the  idea  of  answering  every 
conceivable  question  which  might  arise,  concerning 
the  structure  and  the  work  the  crusher  is  intended  to 
do.  It  is  obvious  that  unless  the  discs,  which  with- 
stand the  crushing  force,  are  made  of  the  most  dur- 
able metal,  the  efficiency  of  the  machine  is  nil.  The 
fact  that  they  are  made  of  '  Era  '  manganese  steel  is 
a  sufficient  guarantee  that  operators  will  have  no  un- 
necessary uneasiness  on  this  point. 

Holman  Brothers'  catalogues  illustrate  the  high 
standard  that  can  be  attained  in  trade  literature.  We 
have  received  the  1912  editions  of  two  recent  publica- 
tions covering  Holman  Hoists  and  Holman  Rock- 
Drills,  Compressors,  and  Accessories.  The  Hoist 
catalogue  (9  by  12  in.,  60  pages)  is  particularly  well 
designed,  beginning  with  a  description  of  the  small 
Stretcher-Bar  machine  and  leading  up  to  the  large 
types  of  steam  and  electric  winding  engines.  We  are 
promised  later  a  separate  catalogue  dealing  with  Elec- 
tric Hoists  only.  Approximate  prices  for  the  smaller 
hoists  are  given.  Each  type  of  machine  is  illustrated 
by  a  large  photographic  reproduction,  and  from  the 
amount  of  information  given,  the  prospective  user 
should  find  all  the  necessary  data  to  formulate  an 
order  for  his  particular  requirements.  The  catalogue 
on  Rock-Drills  and  Compressors  is  smaller  (5^  by  9  in. 
94  pages).  The  list  of  users  of  Holman  Drills  and 
the  letters  of  appreciation  are  convincing.  It  is  in- 
teresting to  note  that  the  works  of  this  company  have 
been  enlarged  four  times  in  the  half  century  of  their 
useful  existence. 


TN 
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