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Full text of "The British journal of photography"

BINDING LIST APR 1 5 1923 



Digitized by the Internet Archive 

in 2007 with funding from 

IVIicrosoft Corporation 



http://www.archive.org/details/britishjournalof65londuoft 



Sifflaaiat, Tai Buna Jovumu. or PaoTooaunr, DeemnlMr 27, 1918. 




J 



THE BRITISH 



JOURNAL OF PHOTOGRAPHY. 



PUBLISHED WEEKLY 



VOL. LXV. 

I91h. 




HENRY GREENWOOD * CO.. I/td., Pcblibhbrs. 24. WELLINGTON STREET, STRAND, LONDON, ENGLAND, 

SALES AGENTS:— NEW YORK, U.8.A , OEOBOE MURPHY, INC.. 57, East Ninth Stbket. 

CANADA : J. O. RAMSEY t CO.. Ltd,, TononTO. 

MBLBOUBN* ; K0DAK(AU8TBALASIA),rvn)., HARRINGTONS. I/n>., J. W. SMALL 4 CO.. WATSON & SONS, jjjd GORDON 4 GOTCH. 

SYDNEY : KODAK (AUSTRALASIA). Ltd.. HARRINGTONS. Ltd., J. W. SMALL <t CO.. ahd GORDON & GOTCH. 

ADELAIDE knv BRISBANE: KODAK (AUSTRALASIA). Ltd.. asd HARRINGTONS, Ltd. 

AUCKLAND: KODAK (AUSTRALASIA), Ltd., HARRINGTONS (N.Z.), Ltd., SHARLAND 4 CO. 

OAPB COLONY, NATAL, BHODESIA. TRANSVAAL ajcd ORANGE RIVER COLONY : LBNNON, Ltd, 

INDU : NADKARNI 4 CO.. BOMBAY. TOKIO : MARUYA 4 CO., Ltd. 



INDEX. BoppUmuil, Tai Butibb Jockhxl or PaoTOOBAPnr, Dtcembn 27, Kit. 



INDEX. 



I 



Throughout the Index the following abbreviations are used to indicate the nature of the references : — 
(Pat.) Patent News. (Cop.) Coppespondenoe. (Soo.) Societies' IMeetings. (Rev.) Review op Tpade Notice. 



Bankpuptoies, 



(Cop.) Coppespondence. (Soc.) Societies' IMeetings. 

(Ans.) Answeps. (Anal.) Analeota. 

The Index includes several Sub-Indexes — 

Companies RegistePed, Exhibitions, Names and IMapks, Tpade, 

which are placed in their alphabetical positions. 



Obituapy, Patents (Authops of), 



Accumulators, cbaj-^lng, on mercury printing-lamps, 

252 

Acetylene generator, home made, 316 

Acid, nitric, deaths from fumes, 70 

Acme Tone Engraving Co., Ltd., notice of dissolu- 
tion, 254 

Actinomcters, step 278^ 301, 307 

Advertisements, line, m BritUh Journal, stricter 
regulations, 133 

Advertising a photographic studio. By M. Blow, 
267 

— the small studio. By J. Clyde-Wilson, 360 
Advertising, Kodak, an Inside view. By B. Bliven, 

U8 

Aerial photography, Columbia University Govern- 
ment School, 89 

Nadar's (Cor.), 643 

— . — review of war achievements, 526 

Aerograph tubing, strengthening, 331 

-Aeroplane, photographing, police court fine, 429 

Air Service, photographers wanted, 464 

Albumen prints, cleaning, 38 

Amateur Photographer and Photography, amalgama- 
tion, 242 

Urst combined issue, 286 I 

Amateurs' negatives, gaslight printing. By D. 
Charles. 42, 67 

American and British photographic journals (Cor.), 
231, 319 

Amidol, keeping in solution, 74 

— White-Band Diomet, White Band Manufacturing 
Co. (Rev.). 384 

— working strength, 341 

Anastigmats, air-space, four-lens (Pat.). A. Warmi- 
.sham and others, 153 

.\nti-splash for dark-room taps, 371 

Approval, apparatus on, (bounty Court action, 241, 
450 

Arc lamps and eyesight, 233 

Architect's marks for materials, aids in photograph- 
ing plans, 32 

Arsenic toning, Kropf's, 336 

.\rt classes for retouchers (Cor.), 507 

Assistants' unions (Cor.), 10, 23 

— training, 646 

\uatrian and German goods, exhibition of samples, 

119 
Axial aberrations of lenses. By E. D. Tillyer and 

H. I. Shultz, 101, 113, 122, 124, 219 



■ANi(RUPTCiE8- 

Heathcote, H. A., 117, Russell, P. S., 474, 850 
186 Thospann, A. E. G., 93 

Hubble, H. J., 198 Wettel, W. J., 186 

Pyke, M. A., 218, 262 
Basement, whole of, what it means. County Court 

action, 34 
Basil, A., on portraiture (Soc.), 306 
Beach photographers fined, 399 
Bee exposure meter, system of using. By M. M. 
Bitter, 170 

(Cor.), 287, 299, 307 

Belgian Artists, Ltd., to be dissolved, 47 
Bellows, pinholes, repairing, 28 

— renovating, 140 

Birmingham War Museum, photographs for, 57 
Blanc &x6, CanadL-in manufactory, 255 
Blinds, studio, arranging and fitting, 434 
Blisters in enlargements, renairing, 259 

■ prints, factors in, 158 

sepia toning, effect of wash water (Cor.), 109, 

130, 143, 176, 187 
Blocking-out, some aids, 330 
Board of Trade Journal, revised form, 22 
Bon MarchS Studios, dissolution, 46 
Books, holding for copying, 183 

— old photographic. By Bibliophile, 100 
(Cor.), 175, 187, 199 

Border printing, 168 
British Industries Fair (1918), 142, 495 
British lenses, superiority (Cor.), 662, 587 
British Scientific Instrument Association, new pre- 
mises, 541 
Bromide shortage, soda bromide effective, 201 

(Cor.), 231 

Bromide pap«r emulsion, soft, on war paper, lO-* 

extra-sensitising, with dyes (Soc), 550 

pyro developer (Anal.), 55 

Bromide prints, after-treatment, 610 

bad quality, causes, 258 

cleaning, 38 

colouring, in oil, preparation (Soc), 217 

improving with I'ajmer's reducer (Soc), 518 

— — knifing v. rubbing down, 50 

— — muddy, from developer in fixer, 50 
I>ermanence of, 75 

remedying colour by re-development (Cor.), 26S 

Brooks, Ernest, awarded Croix de Guerre, 198 
Business Names Act and its applications, 423 

~ -a further regulation, 462 

Busine^ stationery, omission of particulars, pro- 
ceedings under Directors' Act, 218 
Buttons, regimental, photographing, 269 



Backed toned positive transparencies, Doretype pro- 
oesa, 4 

with bronze powder (Cor.), 22 

Background service. By M. Levy, 336 
Backgrounds, light and dark. By F. Eaymer, 369 
— white, lighting for sketch portraits, It 
Backings, makeshift, 28? 



Calachrome toner, 494 

Cameras, film. S. C. Swann (Pat.), 196 

— folding. M. Niell (Pat.), 404 
pocket. O. Water'.ow (Pat.), 350 

— panoramic, F. W. Mueller (Pat.), 585 

— submarine. R. H. Davis (Pat.), 4S9 
Camera Making (R«v.), 362 



Canada, photographic surreying in. Bv M. P Brlda- 
land, 6 ■ * 

— imports, a concession, 350 
Canvasser, fraudulent, sentenced, 46 

— photographers', police-court summons, 241 
Carbon printing in winter, 465 

Carbon Printing. Autotype. A.B.C. Guide (Rev.), 184 
Carbon prints, cleaning, 38 

platino-surface, 121 

Cartoon cinematograph films. J. F. Leventhal and 

another (Pat.), 415 

R. V. Stambaugh (Pat.), 68 

Censored documents, photographic test, 407 
Charges for portrait photography (Cot.), 407, 418 
Chemical Science, What Industry Owes to. By R. 

B. Pilcher and F. Butler-Jones (Rev.), 162 
Children, photographing. By 0. H. Bohe, 151 
Chromium intensifier. By C. H. BothamUv, 111, 123 

Carnegie and Piper's work, 134 

Cinematograph films, cartoon. J. F. Leventhal and 

another (Pat.). 415 
R. V. Stambaugh (Pat.), 68 

— film, developing machine. W. C. Jeapes (Pat.), 

lettering. L. Sawyer (Pat.), 528 

portable apparatus, development at normal 

and high temperatures. By J. I. Crabtree, 379 

— mechanism. F. C. Jessett and another (Pat.), 196 

— negatives, enlargements from, grain in, 401 

— projection. L. McCormick (Pat.), 196 

standards and control. By J. T. Caldwell, 2» 

— shatters. F. C. Hamilton (Pat.), 639 

R. Wardley (Pat.), 196 

Cinematography photo-micro, Shorrocks (Pat.), 573 

— stereoscopic. H. Shorrocks (Pat.), 350 
Closing co-operative, for holidays, Carlisle, 307 
Keighley, 299 

Londonderry, 331, 341, 343 

Northampton, 299 

Sheffield, 287, 298 

Torquay, 351 

Cloud Photography (Rev,), 362 

Coal, gas. and electric current, economy, 316 

Collodio-chloride paper, permanence of, 76 

Collodion, carriage by rail, .senders fined, 186 

Colloid sulphur toning. Lumiire, 3.35 

Colour photography cameras. W. H. Doherty (Pat.). 
106 

screen-plate two-colour. E. H. Tarlton (Pat.), 9 

transparent mirrors for. Hess-Ives Corpora- 
tion (Pat.), 104 

Colour Photography (Foreign Patents), Ltd., dis- 
solved, 34 

Colouring and tinting prints. By W. S. Davis, 279 

— ■ effect of alum (Cor.), 299 

— bromide,^ in oil, preparation (Soc), 217 

— prints, wax medium. By A. V. Qodbold, 311 

preparation for. By Burlington. 355 

and lantern slides with <lyes. 183 

Colours in reception room decoration, 165 
Combination photographs. E. T. Caklicott and 

another (Pat.), 318 
Ck>mmercial photography. By B. F. Welch, 394 

COMPANIES MOISTERED- 

A F A. Chemical Ck)., .4rt Collectors' Assoeia- 

Ltd., 11 t'O". 398 

Art and Humour Pub- Associated Illustratton 

liahlng Co., Ltd., 207 Ag«nol««, S» 



•np;tam«Bl, Tms Burm JotmiiAL or PmawtArmj, Daeamber IT, 1918. INDEX. 



MMMIt 

Braaet tad Co.. Ltd.. MS rred AlMon. Ltd.. 4S0 
Bxftteb PbotocnphJe Bciton, Wallac«. Ltd., 
kUaufictarcn' Awo- *>* 
clatioo. Ltd.. 174 J«well«r», XiBiaturai. 

Britiata Pbotofnphk Ltd., Ml 
PUtca and Papera, KilfaaaoB and Sona, 
Ltd.. tu lU. mi 

Brttiab Photographic Loo«n ttadioa, Ltd.. U 
KawaKh AMoeiktioa. MadcUM Mllet, Ltd.. 
Mt UO 

Briitah Seicatile to- >>« Stadia*, Ltd., lOC 
atraowat If ^rli Aa- Oleo Partra.tt, Ltd.. Sit 
Mdatka. W Parkea, T. P. aad Co., 

Onaaolhtolad iBrtwaitiig Ltd.. Ml 

Co.. Ltd.. W Pbotoeol. Ltd., Ml 

Dalaca, Vcraoa, Ltd.. Koaemoat, Ltd., 474 

4M Tbirlvcll, Ltd., II 

BnoB, Ltd.. IM Victor Pbotocnphica, 

nvqolur VltrMad Ud.. 6«1 

rhotogrsphi* 0». 
Ud. M 
OoMftIo damiopiai Uakt, t*S 
rn ii w i i i, batara. BonatJiit, Mi. IM 
CoMola. Lieat. Araaade, wooaded, m 
Ooavcatlo^ Paouwapkie. coaaaU aaatlas, U 
CaeUdft X-rat taStcaoc), tl 
Co4ifcraUTa PfatU Worlta. n, tUt, m 
(8— altt a»m »n. ltd.) 
CoMtec dartaaad PX>.P. priala. «4« 

— ptUallt la. «» 

— prapariBf arlala. IH 

— ariactloa «t plaU lor dlScrcal claiaM of «ri«iaal, 

— Tartleal, coafortaMa locaaaiac, IM 
Coontchk, Aado-Aaariaaa, US 

— Brttbk pbototrapka latba I'aitad fllataa. S. 0, 

n,it 

— ercauoa, aad tba laaoaaat fafriatar, tie 
la artra aorttaMa, — 



Draperr, re-tttSenlng with aecootine, UB 
Drawing, lucfaliieaa to aati^tanta, 205 
Dryers, print, rotar;, 828 

W. K. Strombcrg and another (Pat.), Ml 

Drying Blma, hot-air chamber. 417 
Drying net for prints. UrilDn (Rev.), 3(2 
Dry-mounting pre^. overhauliiig, 410 

— preventing edging. 433 

— Uuae eaujca lire, DO 

Ensign, UouKhtons (Rev.). tU 

Oyea lor coU>aring lantern slides nnd prints, iSS 

— fnr non-halation platca, 61& 

— in pbotograpby, a review. By A. Seyewetz, 314 
Dye-toned lmag« with copper (errocyanide aa mor- 
dant. By J. I. Crabtree, 337, 374 



B 

Edinbnrib Society ol ProfesaioiuU Photographers, 

SIS. 2SI, 473, SIS. 660 
Elwtrk flood light. By A. Palme, SOS 
Blcelrlc;ty, aatiooai acbeme for cheap current, 27 
■aibioidery, photographing, retonching lor. 234 
laaaeb, phjtographic, L. Crabtree's invention, 2£5 
tmtmj allana, latcmnwnt, 301, 410 



Cark itoppcn. Mhatitata, 
Corfea, BaUac aT ' ~ 
Coawaj bordera. 



Carta, aaUac alrtlgkt. t0 

~ iwaj bordera. rr^wirlM 

By B. A. &. M7 



with portrait aagaUvaa. 



m, itt. US 



Oaay eoracr lor riUar't Moadh M 
Coaaty rho4oflra»Ma Co.. Ltd.. dk«>l<«d. M 
Covtrbw aad lUaiaiaail^ power at laaaaa. By C. 
WelLorBa Rner, 7* 

«l a l*a< (Cor.). I 

Crawford. C. P.. diKhar 

Cat-oat ■ooala, kone auUac. SOt 

OattlOB *rfflataa, «14 



Darkaaad P.O.P. priala, eoyyiat, <« 
Dark-roooi Sttino, aona maatlali. ■• 

— laap (witcbea, a taaifatlaa. Ml 
Dark-alidM^ book-lora. taiaky. lOfaMaf, > 

— eora aad raaaiaMoa. H* 

Daoa lanaftaa Co.. Ltd.. to ba dlaot*ad, 47 

** "~ ^ aaHoivaa. 0B 

Dtana aogabroa. prtallaa traoi. at 

PraaW H t. r atdlat wtt ^jkotoitar. awaraoy la. By 

Depth' Of' JMair«akaJallat lor lar|»acaia pkat» 

frapkt al aoor aoUd ubjaota. I» 
Daaohaa'a aolyaalpMda toaiai tolatloa. t3t 
Darftaa, aMagfaphie. V. Beat (Pat.X tM 
IIKfalay tta Htfttm, Saw M (Bar.). IM 
Developer lor piaaaaa wark (Cor.i, lo*. UD 



pkotoBTOphy, 638 
Boalbh nia Art Co., Ltd., diawtved, SI 
Balarfed aoBalleea. metboda ol makioc, 683 
BalarfeoMala, loeaaaiaf (Anai.), 4«0 

— troai olaeaa aacaUrca, grain in, 401 

— wky baaiaeaa b mlaaed, il 

Eabugiag aad prolecttoa. poiitloa ol Ulominant, By 
.1. Lockatt. t4S 

— boxea, kzad focoa, 383 , 

— eaaal aad bromide paper, catch, 103 

— auioc tba plate, in 

— laatcm. compact iUnminatlog chamber, 210 
aMdemWaf. By A. Lockett. 303 

a e odad refonna, 88 

— leaa lor, 4Bt 

— aMtkodt lor larga negatlvoi, 4M 

— »ilU-rl(aHt«r lor, 408 

— ptoalng paper, to eaael, 173 

— arcret ■cthod. M, 118 

— with mtcnealam ribbon (Soe.). 228 
BraaiiattloB papera bi pbotograpby, 

itadrata, IM 

— qaaitloaa aad aaawer* la photography. City aad 

flalUb. MS 
■snaptlaa for p hotog ra p h ic vorfcera, 443 



tlamptbire 



note* lor 



— lormula. 



wrttiag 



11* 
UJafc 



ns 
(Cor.), n. m. 



Jtrbathaot, M.. photograph* br, 280 
Brttlah Sdaottta ProdocU Eihlbition. S7l 
Boauahlr* lloaaa Photographic Society 
■Mri. B.A.. Sir Prank, picture* at 

BoMO, tu 
War Pbotoaraph* in colour. 118 
WclUagtOB. 1. B. B.. pbolograpba by. 84 
taporU ol photographic giwd* to U.8. aad Swltier- 

■zpoaaiw colcaUlon. H. Klelaen (Pat.). 686 

- dhc. Amtritmft PhoUttaphti (Kev.). 907 

- ladteatoc*. B. Maaby (PaU. 264 

- aMter. W. Dcftcbeweller (Pat.). 218 
, C. LaIoc (Pat.). 280 

Be*. ayiUB ol oalag. By U. M. Bitter. 170 

' (Cor.). 187, ta, »•. 307 

I Blne..r* Jtraerd •»* Dfrw. WellooBW (Scr.), 46, SM 



(Sm Ola* 

ai ~ 

sr 



pravaaUoa. 



I. Crak- 



haaaa, Vaagaard lonaala, 14 
ra, ■adaria>hatapra{ 



. pM* (Be..). 182 

•*•■**• MBoal*, loata lor. By ■. T. 

Clarke, 488 

— opporatoa. A. B. Dolaar (Pat.). 4M 
- toaka. platteotd ■etoj for, in 

DoTolovaMat olaaaulograph Slai at ooraol aad high 
l aM a a t ala f Oi. By J. L Crabtrto. Mt 

— aagallri. la praatiea, iSt 

— of Ih* taaage la a dry-ptala aogaUv*. By P. W. 

■r. Kiwha, til. 4lt. 487 

— laak (Cor.X Ut, BI 

aeotilBB alrMIt (Oir.L IS, 1« 

Di uluplag f I patar, aaa ol Um, S 

DtwMg. ptaeaaUeo. Claroatt. Oittiaa (Berj^ai 

Bt^raa riMa. white-llae, dlaadrtaUgaa. Rl 

" *- , OMdlcatiaa ol. to tUIlar p hotXBattro- 

_~artlBtlal UBht ht atodto, 3 

imtlua la MM* tnm aharp aogativa*. npaUliDc 

Disakltd aoMtan aad tallora, P.P.A. report oa train 
lag far ah ahjgi aph hi aaaloyawat. 2S8 

DtAec. waaCeank* lor. 38t 

Dlitorted pkatoatgpN. W. B. Baker aad oaotber 
(P»t.). M» "^ 

Itoeki. Loadoa, 
Bealm. IM 

Dofttyp*, de lata, itrla ol portrait pholngraph, 2, 4 

— ogaa aovei a«e<rta, 174 



phttagmphy aad Dcleaoe d the 



ByaTMaaHlTeaeee to lalat tanpreaalou, ■* _, ^ 
Sa* aad aoaa la portralUre. By A. Baranoad, 8M 
Byarighl aad are loapa. 283 



rtC'!<imllr .\rt Co., Ltd., diatolvrd, 34 
fair. BnU.h Iadn*trl«* (1*18), 143. 485 
Parqnhar VltrlBed Photographic to., Ltd.. 266 
Pert in portrdtare. 473 
Faaake'a livtr of lulphur toner, 334 
Pemxalllc *en*iti»er. 8M- ,_.,_,. „, 
PerTO-pra**taU prleU of g aad ae l ^t (Cor.), »*» 

— aea*itl**r, 324 _ .. ^ . , ..^ 
riha dryiag roela. K. L. Scott (Pat.). 471 

— aMatirca. eenootlnc U> glaaa, 883 

— nSu. Soe. AaoB. dee Cellnloeea Plancbon (Pat.i- 

aellwloding. J. V- Jordan (Pat.). 672 

PnaM, itrippins ne«*tlv«a for »torage a*, 448 

riadiac a Fain (BcT.), 81 

PlagarnalU. removing developer rtain*^ 

iiiki:; iSdirtSife. aasrifium'SJ.tio., ..4 

' ?i!;i'{jJ?^j:Jir.;."Sra«.,«a.aU ol rate of progre*,. 
By A. w. Warwick. 18 „ ~, 

PItlni. acid hypo, for pyro-rtalned negaUve*. 622 
I - acid, without acetic acid, 408, 415 

_ powrm of hypo ((k)rj. 8* 

- print! in quantity. 172 
' aolence and practice, 14 



lli 



Fixing without hypo, 62 

By D. Ki.ld, 269. 286 

Flash-cabioet for studio portraiture. By R. C. 

Ward, 547 
FIitshli!!ht powders, keeping properties (Cor.), B42 
Focus fikiment lamps in optical projection. By R. 

P. Burrows and J. T. Caldwell, 582 
Focussing screen, ground glass substitut-e. 227 
Foot-power for photographic appliances, 309 
Formula;, developer, Amplified writing (Cor.), 218 
France, export of plates and papers, prohibition re- 
moved. 142 
Free-sitting profiteering (Cor.), 218, 243 
French Photographic Society, restored activity, 421 
Fiictol. V.anguard (Rev.), 57 
Front lighting in pOTtraiture (Soe.), 461 
Fuel economy (coal, gas and electricity), 410 



(H* economy, the flve-slxths order, 186 
Gaalight printins from amateurs' negatives. By 
U. Charles, 42, 57 

— prints, permanence of, 75 
t;eUtlue, action ol hardening agents, 130 

— reticulation, causes. By S. E. Sheppard and F. Ji. 

Elliott, 480 
German and Austrian good*, exhibition i samples, 
lilt 

— formulae (Cor.), 468 

— photographic industry in 1017, 79 
Glas* and chemical action, 85 

— delecUi in negativea, remedying m printing, 26B 

— lor platee, «hortage of supply (Cor.), 375 

— latent imagee in (Ck>r.). 4(»5, 607 

— lead, aod chemical action, 134 

— shortage (Cor.). 407 , , ,„ , .^ 
stripping plato suggeeUd (Cor.), 309 

— wa»te-negative. ailvered, images on. By <^. vv. 

Waggoner, 168, 161, 166 „ „ ™ .-. u 

Olaiing prinU by squeegeeing. By F. W. kimbey, 
383 

— print* on both sides— a method wanted (Cor.), 

451, 463, 478 
Olycln-Johnson* (Rtv.), 240 
Granvillo Studio Ltd., to be dissolved, 448 
Graves, soldiers', photographs of, 631 
Oum-bichromaU process with a new colloi.l (Soe.), 

640 



Hair In portraiture, 298 ,»j ,i 

H and R. Process Kngravmg (X)., Ltd., 11 
Ualattoo: dye* lor plate substratum, 615 
-optical rnVTbanl^m By C. E. K. Mee*. 237 
Halftone blocks, increaM* charges, 212 
Ualfwatt lampa v. arc In projection. Si 

blue, 653 

overrun for studio flashlight, 303 

studio within studio, 3 ^ „ . ,-^. . „^ 

Hoppv Bo4pital. The. By Ward Mttir (Rev.), 20« 
Hafdening ageoU and gelatine, 180 
UIdU lor photographers from motion picture*, uy 
A. Lockett. 679 , . , ,. . 

Holldaya, aaaiatants'. cooperative closing (see v.lo«- 

Honl°e''bSSi?Ta,7.%y 0. E. Hartley, 236 
HikkI for lens, easily made, 161 
Hydroquinone caustic developer, 805 
Hypo-alum toning, 468 

Punnctt tormula, 323 

tin dishes beet (or, 234 

Hypo economy (Cor.), 106 
Hypo^Umlnator, permanganate. 158 
Hyporecovery ^Cor.), 74, 106, 109, 118, 131, 143, 199, 

319 
Hypo-8aver, Cn'aol (Rev.), Secretan, 384 
HvDO scarcity, measures of economy, 63 
Hu?^r and fcifflcld, earlywort (™emorlal l«tare). 

By W. B. Ferguaon, 229, 327, 880, 847 



Ilford, Ltd., dividend, 560 

Illuminating and covering power of leose*. BJ I.. 
Welbome Piper, 76 _ . . ,„ ^ ,« 

Indiutry, PhotograpMe. of Oreat Briiam (Rev.), 188 
Intensification of llat negathfes, 422 

- sensitometry of. By A. H. Nieti and K. Huse, 

Intensi'fler, chromium (Traill Taylor lecture). By C. 
H. Bothamlcy, 111, 123 

— mercuric-iodide, one-solution, 503 ..,«^„. 
Interferometer, use of, for testing optical systems. 

F W Twyman, 556, 667 „ , j 

InteJiiatlonal Xrtlst.' ciub.. Ltd., to bo dissolved. 

47 
Iodide In the developer, 497 
Iodine reducers, 81 _ „ „ • ooa 

Iron printing procesae*. By C. Priscman, 324 



INDEX, Bnpplement, Tbs Brriw Joubmal or PmnoatjMa.jyteemhn 37, mt. 



AUTHORS' INDEX. 



Baker, T. I.— 

Photography of metals, with X-rays, 68S 
Benson, D. E.— 

Convenient and accurate photometer for the 
measurement* of photographic densities, 224 
BMUOPHaE— 

Old photographic books of note, 100 
Bitter, M. M.— 

Perconal system of using the Bee meter, 170 
Blivek, B.— 

An inside view of Kodait advertising, 148 
Blow, M.— 

Advertising a photographic studio, 267 
BOHI, O. H.— 

Portraits of children, 161 

BOTBAHLET, C. H.— 

Some minor process of photography, 128, 136 
Bridgland. M. p.— 

Photographic surveying in Canada, 6 

BliRUSOTON— 

Preparation of prints for colouring, 356 
Burrows. R. P., and Caldwell, J. T.— 

Focus illument lamps in optical projection, 682 
Caldwell, J. T.— 

Standards and control in cinematograph projection, 

Charles, D.— 
Gaslight printing from amatenis' negatives, 42, 67 
Outdoor lighting, 447 
Short-focus lens in portraiture— the case against, 

CLARKE, H. T.— 

Kxamination of organic developing agents, 4»9 
Clyde-Wilson, J.— 

Advertising the small studio, 360 
CODSINS, G. 0.— 

Light-sources and their applications, 636 
Crabtree, J. I.— 

Nature of a developer sludge, 87 

New method of obtaining dye-toned images by the 
use of copper ferroeyanide as a mordant, 367 

Portable apparatus for developing cinematograph 
film at normal and high temperatures, 379 
Davis, w. s.— 

Colouring and tinting prints, 279 
Uebbnham, W. E.— Short-focus lens in portraiture: 

its occasional usefulness, 558 
Elliott, F. A., and Sheppard, S. B.— 

Eeticulation of gelatine, 480 
Fbrodson, W. B.— 

Accuracy in reading densities, 214 

Early work of Hurter and Driffield, 327, 339, 347 
FISHENDEN, R. B.— 

Lithographic textile printing, 456 



UODBOLD, A. v.— 

Wax medium ;ind process for the permanent 
colouring of photographs, 811 
Graham, J.— 

Some everyday volatile solvents used in lAoto- 
graphy, 628 
Hammond, A.— 

Eyes and nose in portraiture, 326 
Hartley, O. E.— 

The book of the home, 286 
Havens, J. W.— 

Timing shrapnel with the camera, 203 
Hbsr, K., and NiETZ, A. H.— 

Sensitometry of photographic inten«iflcation, 179, 
191 
KIDD, D.— 

Fixing prints without hypo: some preliminary ex- 
periments with P.O.P., 269 
KIMBET, F. W.— 

Glazing prints by squeegeeing, 383 
Krohn, F. W. T.— 

Mechanism of development of Image in a dry-plate 
negative, 412, 426, 437 
Lbpfmann, H.— 

Permanence in photographic prints, 366, 370 
Levy, M.— 

Background service, 336 

Window display of specimens, 169 
LOCKKTT, A.— 

Formula for tetephoto separation, 291 

Hints for photographers from motion pictures, 579 

Modernising the enlarging lantern, 883 

Position of the illuminant in enlarging and pro- 
jection, 248 

Renovating apparatus and accessories, 148 

Mackie line: some new facts and experiments, 67 
Mees, C. E. K.— 

Optical meebanisra of halation, 237 

NifiOL, O. M.— 

Covering power of lenses and stray light in the 
camera, 41 
NiETZ, A. H., and HoSE, K.— 

Seusltometry of photographic intensification, 179, 
191 
Orange, J. A.— 

Scientific design in optical projection, 51, 66, 78 
Palme, A.— 

Electric flood light, 303 
Phillips, R. W.— 

American war-time notions, 491 
Piper, C. Welborne.— 

Covering power and illuminating power of lenses: 
tests and performance, 76 



Priseman, C— 

Iron printing processes, 324 
Rawkins, R. R.— Plate-marker for three-on po»tc&rd 

strips, 211 
Rather, F.— 

Light and dork backgrounds, 369 
Renwick, p. F. — 

General features of the F.E.B. photometer, 218 
S., E. A.— 

Cosway borders, 867 
Shepparb, Dr. S. E.— 

Effect of iron on ammonium persulphate reduce' 

Sheppard, 8. E., and Elliott, F. A.— 

Reticulation of gelatine, 480 
Shepherd, R.— 

Liverpool Amateur Photographic Association, 298 
Shultz, H. I., and Tillyer, E. D.— 

Axial aberrations of lenses, 101, 113, 124 
Stebbins, O. S.— 

An experience of mechanical retouching, 465 
SURDAM, Mrs. M. C— 

Science of salesmanship, 392 
Tennant, J. A.— 

Portraits of women, r>m 

Window display, 182 
Thomson, J.— 

Plain salted paper, 403 
Tiinby, F. C— 

A personal impression of the London Salon, 435 

Personal impression of the R.P.8. exhibition, 468 
Tillyer, E. D., and Shultz, H. I.— 

Axial aberrations of lenses, 101, 113, 124 
TWYMAN, F.— 

Use of the interferometer for testing optical sys- 
tems, 556, 567 
Waggoner. C. W.— 

Images on silvered wa^te-negative glass, 161 
Ward, E. C— 

Flash-cabinet fOT studio portraiture, 647 
Warwick, A. W.— 

Fixation of prints, 16 
Welch, B. F.— 

Commercial photography, 394 
Westman, W.— 

For the receptionist, 337 
Weston, 0. C— 

Lantern slide-box for postal transit, 28 
YOUNG, E. D.— 

Matters of professional moment, 469 



HENRY GREENWOOD & CO., Ltd., PUBLISHERS, 

24, WELLINGTON STREET, STRAND, IN THE COUNTY OF LONDON — Dbcembkb 27, 1918. 

Printed by St. Olckehts Pmbs, Ltd., Portugal Street, Kingsway, in th« same County. 



THE BRITISH 



JOUENAL OF PHOTOGRAPHY. 



No. 3009. Vol. LXV. 



FRIDAY, JANUARY 4, 1918. 



Pkice Twopence. 



Contents* 



»*•« 

1 



BsC4xsBamA 

Dirrctss fn»i - 3 

Tat Doaarm — A Dm LeZB 

!im.a Mr PwrrmAiT PanniMim 4 
Psaiouuruc Brarsna* n 

Cakasa. Bf M. V. BrMdMd . . S 

DrtTB or Mb. r. A. Busas .... t 

DiATa or Mm. O. A. Bean 9 

Ami«ta]>t*' N«m 9 

Patut Msw* 9 



AiiAi.aaiA ... 
Kn-naM or 

Th« Itov In, Umltod, mad the 
pp.!. — AMistmnu' Urnkma — 
Tkt anattaaMtrr of Fkoto- 
(rafhla Pmpmn 

Coiumaui AKD LmoAK Iimi.- 



ii*a« 



10 



n« 



o/ eaml mU wkieh iw«ai% ceeupitt tk$ U^cm half 



of tkU erimmn inll bt found at Uu foot of th4 yagt ovtrUaf and 
tnll einiimmt to bt plaetJ Ih^t tckiUl 



ftf 



rtUim$ to Urn Jartktaml^g 



lit regular poiition it rt^ired 

DJ A 



On»*ntf«ix, and Good V«lu« at That. 

This u what t-be \eu-tpa-per World *ty» of the Almanac. 
It haaa't M«n • copy, for th« fint «>inpl«t« oopy will not 
be aT»ibbl« for a week or so, but n«vertheleM it ia ready 
to pledge itoelf that the Ahnanac will be worth buying at 
a 50 per cent, increase of price. 

Ana the .Vetrtpaper WorlJ. which week by week 
betray* it« oloae sense of how Fleet Street liv«a and 
moves and has ita being, knowb tJiat it can safely sav so. 
How does it know that? Well, with tii« journalist's 
insight, it realises that in these hard times, with paper 
costing 400 per cent, more, them are only two things for 
the publisher of a rather fat l>ook like the Almanac to 
do: — (1) Suppress its iaane except to the extent of main- 
taining the copyright, or (2) mak* a decent thing of it, 
and bring it out at a price which ia Mmie Mt .off against the 
enormously increased cost. 

That is, in fact, just how a puUisber will look at the 
proposition in these days of paper rationit — and paper 
prices ! Ordinary standard!) of policy are knocked as 
high as a kite. It ia not a question which of two alter- 
natives pays better. There is probably not much to 
choose between the two in that respeoi. Six Almanacs 
for copyright purposes are • 'wtamty in the way of 
■avoiding loss: 15,000 for sale mxy make a few pounds, 

Thus, in deciding on the latter, the publishers say:— > 

While we can produce a re.illy good Almanac, fully 
worth its price, we will pro«hir. it. When we absolutely 
can't will be time fnoug-n to -t«>p." 

So the 1918 Almanac will mme to ita readers with a 
ort M sate of merit written, so to speak, in the circum- 
o'aiMSw of tlie time. It will be a good one simply because 
r. 1mv« been worth while to work for, say, four 
-u a job which after all couldn't be done well. 
Ill short, we would rather yield to the pressure of the 
tiriKw than offer a book which shonld disappoint a single 
laader of iu ■ ny annual predacessBia. . ^. _ . 




EX CATHEDRA. 

Damp- Proof The present persistent spell of peue- 
**'**'*'*'■•*•• tratiugly damp weather, or perhaps we 
ought to say the alternations of damp and frost, which 
are worse still, make it expedient to give an eye to show- 
oases which are situated away from a studio, and, often 
from their exposed position, are particularly liable to 
suffer from influences of the weather. In many instances 
such show-caaee are little better than heavily-built pic- 
ture frames, and are in no way competent to withstand 
the ingress of moisture. The present seems an appropriate 
time when photographers could overhaul these pieces of 
advertisement apparatus; not infrequently they woiikl 
find that they could very greatly improve them. We 
regard as an essential feature of such a show-case tJie 
provision of means by which the complete display can 
be removed in a few seconds, and its place taken by a 
fresh set. If this can be done by sandwiching the 
mounted photographs between two sheet-s of glass which 
are bound together passe-partout fashion the trouble 
from damp will largely disappear at the same time. It 
is not difficult to adapt an existing show-case to this 
system, and in designing new ones it its a comparatively 
simple matter to provide a fairly substantial foundation 
for the baok part of the case and to form the front with 
a picture frame of fairly heavy moulding, within tihe 
rebate of which the specimens in their passe-partout bind- 
ing can be inserted and retained in place by one or two 
turn-buttons. A lock and key for the front frame, 
wliich is hinged to the foundation, then completes the 
appliance, the damp-proof qualities of which may be 
further enhanced by providing facings of rubber on the 
rebated front of the foundation and on the back of the 
frame, and adjusted so that the pressure on the latter when 
the whole is locked brings the two into firm contact. 



Copyright Although the main provisions of the 

ipao faoto. 1911 Copyright Act appear to have 

•me familiar to photographers, it is somewhat strange 
^e one point in regard to which we receive perhaps 
queries than upon any other marks almost the most 
fundamental difference between the present and the pre- 
vious legislation. It is that no registration or any other 
formality is necessary in order to secure copyright in a 
photograph or any other form of artistic work. Many of 
our inquirers seem to think that they are in a position of 
insecurity unless and until they have done something 
which is akin to the registration at Stationers' Hall, 
which was a necessary formality under the old Act in the 
creation of copyright as an asset in the eyes of the law. 
Let them reas-sure themselves. Under the pre.sent Act it 
is not necessary to do anything. The very fact of taking 



THE BRITISH JOURNAL OF PHOTOORAPHV. 



[January 4, 1918. 



a photograph automatioally creates the copyright in it. 
The question is to whom does the copyright belong ? And 
here photographers are on familiar ground, because, 
with certain minor qualifications, the new Act is on all 
fours with the old, inasmuch as the copyright in a photo- 
graph which is ordered by any person becomes the pro- 
perty of that person, whereas if the work is done by the 
photographer "on his own " the copyright is his. These 
and the score of other less simple points which crop up in 
copyright law are exhaustively dealt with in the shilling 
manual " Photographic Copyright," which our publishers 
issue. Apparently photographers purchase it -when they 
find themselves in some difficulty — then to discover that 
they would have been pounds in pocket by an earlier 
knowledge of its pages. 

# » « 

Making a A point which is overlooked by many 

Name. photographers is the value of a name 

which is a household word in the mouths of the public, at 
least in their own locality. If a man depends upon his 
show-case and the recommendation of his client^lf he 
may do a fairly satisfactory business, but he is in the 
crowd, and must take his chance with others. If, how- 
ever, he has managed to bring his name prominently before 
the general public, the person who wants a portrait is 
very likely to seek him out because he has an idea that 
he is dealing with a prominent member of the profession, 
and, therefore, likely to get satisfactory work. Such a 
reputation can be gained, firetly, by doing good work 
and giving willing service to all comers, and then every 
chance, no matter how small, of gaining desirable pub- 
licity must be seized. Municipal work on town councils, 
school boards, relief committees, and the like contribute 
greatly to the desired end, and an occasional letter written 
to the Press on any subject of the day is another stepping- 
stone to the same ])oint. If people constantly see sensible 
letters on any subject, from food queues to archaeology, 
signed with the same name, they are likely to inquire as 
to the identity of the writer. If Algernon Ashton and 
the Rev. J. Bacon Phillips happened to have been photo- 
graphers the notability they attained by their letter 
writing would have been worth much from a business 
point of view.^ Day by day a careful look-out must be 
kept for openings for self-advertisement, and no ciance 
however small allowed to pass. 



Doretypes. On another page we reprint j)articulars 

of a process which is just now being put 

before photographers in the United States as a means of 

providing a form of portrait photogiaph of rich distinctive 



SUMMARY. 

In the United States piximinence is just uow bekig given to a form 
of photograph oonsisting of a thin toned x>ositive transparency on 
glass backed by paper, silk, or a coating of bronze powder. Such 
photographs, in a dioice seating, are reooinmended as a novelty for 
studioe which can secure the good prices which their appearance 
justifies. The name given to them is Doretype. (P. 4.) 

Some notes on the diffusion of light, particularly in respect to the 
use of the various forms of artificial light in the studio, will be found 
on page 3. 

We repeat, for the information of many who seem not to realise 
the fact, that copyright in a photograph is created (without any 
registration) by the laking cf the phoU^rapli itself. (P. 1.) 

A tontributor to "Assistants' Notee " describes how to repair 
tK)ok-fonn dark-slides which have become leaky at the jonctioin o€ 
the two halves. (P. 9.) 

We regret to announce the death of two well-known figure;^ in 
photographic circles, thoi^ of Mr. F. A. Bridge, for many years 
Secretary of the Photographic Convention, and of Mr. C. A.liooty, 
one of tJfie oldest commercial i-eipresentativos connected with photo- 
graphy, and of late years associated with the sale and transfer of 
businefses. (P. 8.) 



appearance", yet capable of being j)roduced at a compara- 
tively low cost. The aim of the promoters has evidently 
been to originate something which in its way can be 
prized by the possessor just as the Daguerreotype minia- 
tures were prized in their day. After one has discounted 
the familiarity of the jmblic with all kinds and descriptions 
of photograph, it would certainly seem that there is still 
a promising field for originality of this kind. Moreover, 
the new process ha-s the good feature that it is not one 
which can l>e turned over to the tender mercies of any 
half-skilled maker of bromide prints, but calls for a degree 
of skill (in the making of the glass transparency) which 
sufficiently puts it out of the sphere of the cheap imitator. 
Like everything else, it can ]ye done badly ; but the result* 
which the cheap man is likely to produce will hardly bear 
comparison with those which are easily producible by 
printers of experience. As we ]X)int out in some notes, in 
introducing the communication, there is nothing essen- 
tially new in the method, which is a resuscitation of a 
dodge which has been practised now and again by makers 
of prints for exhibition purposes. 

* * * 

Matt or One of our colleagues of the American 

Matte — photographic Pie.;s has recently written 

to us in terms of mild remonstrance as to our use of the 
word " matt " in description of printing papers of mir- 
fiaoe other than glostiv. His objection to " matt " is 
that at is a German word, currently used not only in its 
photographic connection but in others, for example, as 
mate or checkmate, in chess. It is suggested that the 
form " matte " is preferable, and is the s{>elling which 
is commonly adopted in the United States. To our mind, 
however, the choice of one or the other is an item of such 
triviality that we oannot believe it to be of any real 
importance in contributing to the benefit of the trade in 
photographic 'prin^ng papers among either ourselves or 
our friends in Amevici. Personally we use " matt " 
because it has for so long a time been sanctioned by 
custom, land after looking up the synonyms and alterna- 
tives in the dictionaries we conclude that it would be 
difficult to justify the choice of a better form on grounds 

of etymology. 

* * * 

—and While we are upon this subject we wish 

Gaslight. we could prevail upon our American 

brethren to do something which will remove the ambiguitf 
which exists in reference to the description of the 
printing papers, which perhaps are more used than 
any other, and have, in fact, their origin in the 
United States — ^we mean " gaslight." In the Unite 
States during the past few years, doubtless as the 



The making of « mo.saic oolour filter, of regular or irregultu: 

•pattern, for screen-jjlatf colour photography according to a two- 
colour process is the subject of a recent patent specification. (P. 9.) 
A recent i.'isue of tihe " CJeographiciiu Review " contains a valuable 
summary of the methods of surveying iby means of a camera whick 
of late year.<; have been officially employed in Canada. (P. 5.) 

" Coi.OVH PuoTOGRAPHV " StTPPLKMENT. 

In a communication on photo-mcrography in colours Dr. C. E. 
Kenneth Mees instances tlie special retiuirements of the photo- 
micrographer. and outlines a pioce.ss. worked out in the Research 
Lalboratory of the Eastman Kodak Comiiany, which has been found 
suitable and practicable. (P. 1.) 

The current instabnent oi tJie " Decenuia Practica " of colour 
photography deals with various defect* encountered in Autochromc 
transparencies, Kuch as iblack spots, frilling, and predominant tini. 
It makes mention of preventives of these, and of remedies in ihe 
shape of pale tinting screens for use when viewing or projecting. 
(P. 3.) 

It is Te}K>rt6d from Fr.ince Uiat a new method nf making a colour 
screen-film lias Weu worked out bv M. Dufay in asfociation with 
MM. Lumiere. (P. 4.) 



Jlnuarj- < 191^1. 



^Wrf ^ITtStf jd§RN'4iKb^¥H<&T0%*APK.¥. 



itsUt 9f fibe wideaprMul use of olectric light 

" gaslight " as a description oi the paper 

" Velox " was the original type has 

place has been t-aken by " develo] 

ing-out," often written as 

out paper). There is thus 

that in the matter of 

thiug different between 

paper, for the latter 

ATiters on and makers 



the word 

of which 



D 

•rea' 




thei ^ 

r andr^wtamde 

.survives among 

papers 



deve. 

gaslij: 

nanip still 

of bromide-emulsion 
in America. And to swine round to, our country again, 
janiiot someone think of a generic name which can be 
applied to the now fairly nuiiierona papers which as 
regards speed fall more or less definitely in a class by 
tbeniselves between gaslight ami bromide? Up to the 
present " slow bromid* " appears to be the beet general 
name which can be applied to these. 



DIFFUSED I.IOHT. 



be broadly 
In the case 



Light as used by the photon; t-apher may 
divided into two classes, direct and diffused, 
of daylight these are exemplified by direct sunshine and 
by, the light reflected by clouds, and in that of artificial 
light by the rays proceeding from an unscreened electric 
arc «nd those refle(4«d from the same light by « white 
Mireen, the arc itself being i' m the position of 

the subject. We sxe all fsL ..e effect of thec« 

two lightings in portraiture, tlit> direut sunlight giving the 
harsh lighting «o often seen in iOiapshot portraitd, while 
the refleoted light gives a more or leas soft illumination 
according to the degree oi diffusion and the skill with 
which the light is n.«iMpuIated. Between these two 
extremes there are many grades. Even the light from a 
white cloud will give what a photographer oalls "over 
lighting " if sofoe further diffusing arrangement is not 
employed, and many port-raits are spoiled for this reason. 
Hence we have the predilection of many operators for a 
studio glased with ground glass, or having the glass 
severed with waxed paper. Where <hrt><it sunlight falls 
ujHjn the s;ULm during working houri t!r in necessary, but 
ni" -eens covered with tri t-r, as employed 

b^ •• Mr. Valentine Bta:; ; who successfully 

worked in a studio with a southern aspect, are much to 
be preferred. In dull weather, and at such times as the 
sun is not shining directly UT>on the glass, they may be 
removed, the exposure shortened, and more vigorous effeots 
obtained. 

M.inv ir-T .-- — ! > ■ r/raphers fall into the error of 

iniy be ren.edifl by using a 
redector to illuminate the shadow side of the sitter, 
oblivious of the fact that it i« not so much that the 
shadows are receiving too litth- light, but that the high 
lights that are receiving too nnuh. A simple fxj)erinieiit 
will ^how if the illumination is sufficiently scft for ordi- 
nary portrait work. If we set up a rod, say, an ordinary 
walking-stick, about a foot in fniit of a white background 
and find that it casts a TTi'"^" ''^ sa " 
it is a proof that the li. too 

a light will oaat a shadi.'W m i le nose U]x>n the sitter's 
che<ilt. and pR>babIy show sharfi shadows in the drapery. 
We must now either introdti«p> further diffusion by nie.iJis 
of a tranaliMicnt screen, such .is the ordinary drcular 
" the rod and background further from 
shadow i.« n!tW5?* lost. It Is usually 
most in evidence, as 
I" j; the sitter. Hence, 

in such places the head screen is the only renifdy. 
The tyro is often reluctant to do thia, because he fear? 
that sadi a redooUon of light wifl entail a greatly in- 



head *' 
the 1i> 

in 



oKiased exposure, but upon trial this: will m^ Be found 
the case. Anyhow, we must give enough exposure to yiejd 
]toa||M||ary derail in the shadows; and as these -..are 
i^H^ateB by rftffecrfed light from a white screen or the 
**%*f the stiiijio.it will be found that little more 
expoSJSfe.is neoe«saiv for this, while we can afford to givie 
iiiuri- ]i dull, '("<.! flfvplopjiient without causing the hiffh 
Ug^ti to be blocl;ed xipi Skilful artiats can do wond^ra 
wifefa- concentrated light, but the tyro will find the couris 
we reoomniend a safe one. 

It is often found that an operator who oan do go<Kl 
work in a daylight studio fails' wheii he attempts to use 
electric light, and he is apt to attribute his poor results 
to the nature of the illuminant rather than to his own 
want of knowledge of it. taking as an example of con- 
centrated light a single enclosed arc lamo, we shall find 
that when used without a screen we have sharp, clearly 
defined shadows. If we interpose a thickness of tracing 
paper near the lamp we shall still obtain decided shadows, 
but the outlines wiir be softer. If we 'iritrcduce a head 
screen covered with thin muslin or tracing cloth the 
shadows will be .-oft and their outliiiee indefinite, while 
we are able to develop all shadow detail without losing the 
modelling in the lights. It should be noted that the 
nearer the head screen is brought to the siliter the ihore 
the inteasity of the high-lights is reduced. In fact, it^'is 
possible to equalito the lighting on both sides of the fa«a 
if desired. U mUft net be forgctteii ithat a reflector must 
receive light before it can reflect it, so that tho diffusfer 
must not be placed so that it prevents light i-cachiiig it. 
Another useful inethcd of securing a soft lighting with 
such a lamp is to place a white screen behind it, and to 
cut off all direct light by means of a saucer-sha}>ed enamel 
reflector placed so as to cover the arc. It may be well to 
mention that the ofien arc is also caipable of being u.sed in 
this way, as well as in the familiar uiubrella-shaDed 
reflector. One important factor in lighti^ig iar th.it "cff 
distance. Even with reflected Hglit alone it is possible 
to obtain cast shadows, and tho remedy for these is either 



to place the sitter farther from the light or to interpose 
a diffusing screen.^ a very neat way rt doing this being 



s lieb 
y OT 
that employed in Marion's "North light." 

Half-watt lamps form a class of their own, although 
to a certain extent they may be placed with arc lamp. 
A .single high-powft- half-watt bulb requires treatiiieBt 
similar to an enolcsed arc. It may be used either with 
diffusing screens, or the light may be directed upon -a 
white screen by means of a hemiepherical reflector. -Tfie 
greit advantage of the half-watt system is to be found 
in the fa*! that a number of small lamos may be used, 
thus pro\'iding a large area of illumination without having 
to waste light through thick diffusers. Even half-watts, 
however, should never be used without at least one trans- 
lucent screen, the metal reflectors supplied not being large 
enough to give alone the necessary diffusion. Here, again, 
the factor of distance oomes in. If the lamps ape far 

enough from the sitter the small diffusers supplied with 

clearly defined shado*. .iliS'P """* ""^^ient, but if the lamps are placed close up 
o concentrated Such TSSUighting will result if no additional diffuser be used. 

Moist Pbicks.— -Mwsru. W. Butcher ami Sons, Camera Houfe, 
Farriiiifdon Avenue, I^nidon. E.C., announce that as from January 1, 
1913. the followin? advances on the cjitalf«riie prices of Uieir'list 
i»«iic<l Jtuniury, 1917. wil) ly made: — Plate Sunk Mounts, advaroe 
100 per cent. ; .Moi'mUm?, Ticket and Duplex Hoards. ridvT'n''e 125 
per cent. ; Mao-Uxir", Re«Tent and Linette Papers, advanop 100 per 
cent. : Paste an .M'lunta a<fvan<'e 75 per c^nt. : S'ip in Mounts. 
".Hvairo 50 per cphI. Oardeo Enve'op?«. All Prices Withdrawn. 
Pr-crs on appl'cwt'nn NotTitive Ba«s and Fnvplnrnea. advnnre 150 
r»tv* cc'it. : Book I* '■•■rs, advance 200 per cent. A new 



< 't>i< me ia o»w in p 
The alxjve o<Iv.inces 
cnt'ilc;^!?. 



in whioh all prices will be re-adjueted. 
'inr^ed p.'i:dmT; the issue of the new 



THE BRIIISH JOURNAL Of PHOTOGRAPHY. 



[January 4. 1918. 



THE DORETYPE-A DE LUXE STYLE OF 

PHOTOGRAPH. 



PORTRAIT 



We are interested in noticing in the current issue of the " Photographic Journal of America '' that the Eastman School of 
Professional Photogrnphy is just now popularising in an improved form an idea which will carry some of us back to exhi- 
bitions of the Royal Photographic Society of more than twenty years ago. The Dorctype, as it is called, is a thin positive 
transparency on glass, the characteristic textural efleot of which is obtained by backing it witl silk or paper or even with a bronze 
powder. The method of its production is thus substantially the same as that of a ])liotograph entitled "Tlie Grand Turk" 
which was shown at the exhibition of the R.P.S. many years ago, and which at the time attracted considerable comment. The 
method, however, is now put forward as a means for making quite small photographs, which, by their no^•t•l character and by the 
appropriateness of their mounting, may form a novelty for photographers' showcases ; at one and the same time inexpensive and 
easy to produce, j-et capable of commanding a good price. The details which we reprint .below will make it siifficiently clear 
within what range the Doretype is capable of variation.— Eds. " 11. J." 



The new style of picture, the " Doretvpe," which has recently 
been introduced to the photographic trade through the Eastman 
School of Professional Photography, has met with an unusual 
amount of favour from coast to coast. 

Photographer.s who have taken uj) this new jirocess with the 
idea of making every picture as attractive as the pix)cess per- 
mits have been successful. Doretypes sell at prices that 
ensure a good profit and permit the necessary amount of care 
to be given each piece of work. 

The popularity of the Boretype is due to its unusual attrac- 
tiveness, but the effectiveness of the picture depends in a 
great measure upon the setting it is given. The Doretypes 
shown at the Eastman School are mounted in handsome leather 
cases made specially lor these ])ictures by Tajjrell, Locmis and 
Co. The pictures in themselves are beautiful, but a handsome 
case becomes a part of the picture ;ind adds materially to its 
attractiveness and to the photographer's ])rofit. 

With edges sinij)ly bound or the picture mounted in a frame, 
even though it be the best frame you can buy, much of the 
attractiveness of the Doretype is lost. You would not think of 
framing a Daguerreotype and, like the Daguerreotype, the 
Doi'etype needs a fitting setting to show it to the best advantage. 

The Doretype is a warm-toned, thin, positive image on glass, 
and receives its brilliancy from the material which is used to 
back it up. It lends itself to almost any treatment may 1)6 
backed with light-tinted papers or various shades of fine silk 
or satin, but the most satisfactory method is to coat the baci' 
of the transparency with a fine gold bronze. 

The following instructions will give a fair idea of the method, 
and a few experiments will enable you to determine how the 
best results are secured. - 

The first requirement is a clear, thin positive from an}- good 
negative. From large negatives the positive should be made 
by reduction, as the most attractive Doretypes are in small 
sixes. Give full time and soft development, so that the positive 
will be thin but full of detail. If you must work from a flat 
negative, a " contrasty " developer will be required; if your 
negative is "contrasty," a soft developer will be required; 
while if you have a well-balanced nonnal negative, a normal 
developer will give you the best positive. The positive must 
be thin, because the effect of brilliancy is secured by the 
light reflected from the material used behind the positive. A 
Seed 23 plate will give the best result in making these positives. 

When the positive has been developed, fixed and thoroughly 
washed, it should be re-developed in the re-developing solution 
recommended for giving fepia tones on Eastman bromide 
paper. 

Make uj) stock solution as follows ; — 

No. 1. — BLEAOiixfi Solution. 

Potassium ferricyanide 5 ozs. 

Potassium bromide 5 ozs. 

Water 120 ozs. 



No. 2. — Ke-Developlng Solution. 

Sulphide (not sulphite) of soda 5 ozs. 

Water 60 ozs. 

Prepare bleaching liath as follows ; — 

Stock solution Ni>. 1 4 ozs. 

Water 4 ozs. 

Prepaiie re-develojier as follows : — 

Stock solution No. 2 1. oz. 

Water 8 ozs. 

Immerse the positive in the bleaching bath, letting it remain 
until only faint traces of the halt-tones are left and the black 
of the shadows has disappeared. This operation will take 
about one minute. Rinse thoroughly in clean cold water. 
Place in re-developer solution until original detail returns (for 
about thirty seconds). Rinse thoroughly, then immerse for 
five minutes in a hardening bath composed of 1 oz. of the 
following hardener to 16 pzs.. of water. 

Water ;.. 5 ozs. 

Sulphite of Soda, li. K. Co 1 oz. 

No. 8 acetic acid (28 per cent.) 3 ozs. 

Powdered alum 1 oz. 

The re-developed positive is thoroughly washed and dried 
and very carefully spotted. It is now ready for backing. If 
silk is to be used, only the lightest shades and finest surfaces 
will be found suitable. If tinted paper is used, an enamelled 
or very smooth surface is best. Lay the positives on the 
material to see what the effect will be. If several positives of 
the same subject are developed to different strengths it -will 
be easy to determine the best quality for Doretyi>e i-esults by 
placing the several positives side by side on the same material 
and comparing the results. 

If Doretypes are to iie tinted, transparent colours should 
be used, and these should be very CiU'efully blended; too little 
colour is preferable to too much ; a delicate tint against a light 
background will be foiu.d most pleasing. When silk is used as 
;i background it should be backed up with cardboard, cotton, 
and paper. Cut a piece of cardboard the size of the positive, 
lay a piece of cotton batting on the cardboard, cover the cotton 
with a heavy sheet of white paper, and place the silk over 
this. Lay the positive on the silk, being careful to see that it 
it not wrinkled, and passe-partout the ^lositive and backing 
together. By applying a slight pressure while binding the 
edges the cotton will hold the silk in good contact. 

One of the most generally used methods of backing is to 
coat the film side of the positive with gold bronze. It is neces- 
sary to use care in selecting the bronze i)owder, as these pic- 
tures are very often small, and a coarse grade of powder will 
give a coarse grain to the picture. A dark gold bronze gives 
a dull effect that is not pleasing. The best- effect is secured 
by using a very fine, natural-gold-colour bi-onze that will worlr 
very smoothly. In most cases this powder can be supplied 
by the photographic stock houses in 1-oz. jiack-iges under the 



Junv/ 4, »]&'] 



fPtlB 'BRITISH jOURNAL^ OP PHOTOORAPHy. 



. '-f- 



:i«me ' Li^ht Hold phijtu-cvatn r.'IMjus .powder piiisf 

b« ooinbiii«d with a liiiuid, and ii is ::ii]>ortant to use one that 
will not aBect the silver derposit or the gelatine, and that is 
a* nearly coloorlesa as poaaible. TIk> dark-coloured bronzing ' 
liquids change the oolonr of the l.ronze and the effect of 
brilliancy is lost. The best thinj; »e have been able to find 
fur liquefying bronze powder is 1,'intem-slidt^ film varnish. 
This varnish is colourless, dries in aboat thirty minutes, and 
does not affect the silver image or the gelatine. Use a small 
amount of the bronze powder, and add ramish until the mix- 
ture is about the consistency of thin paint Apply it to the 
film side of the transparency with a Hat camel-hair brush about 
]-inrh wide, and allow to dry with the transparency lying 



perfectly Bat. ft 3Iie*l)ronze. shows 'brdsh-marks when'Sry it 
has be<?n applied when too thick. The solution should be thin 
enough to flow together, should be applied quickly, and shoiii; 
not be eone over once the entire surface has been covered. 

With this method the finished picture should also be backed 
and edgfs bound to pn.tect it from moisture. If the positivo 
have been properly handled the results will be as permanent as 
the silver image itself. 

Don't make Doretypes in large sizes ; don't show them except 
in appropriat« cases ; dun't look upon them as cheap novelties. 
They should rank with miniatures, and they surely give you the 
(>j)portunity to offer your trade something out of the ordinary 
for gift pictures. ;., 



PHOTOGRAPHIC SURVEYING IN CANADA. 



:*i 



[Aa wo eodaaTonred to show m a recent editorial article, one effect of tbi- recent rapid development of aerial navigation is 
almoat bound to be the much mora extenaive application of the cainera to surveying. The employment of an aeroplane ns 
the "base" for a sorreying canxra opens up an altogether new development of what in the past in this country has been 
a very much neglected iDetbo<l of map-making. Among Italian and Austrian surveyors, no doubt as the result of the 
mountainous nature of a great denl of itie terrain ovpr which they have had to operate, photograpliic methods in the past 
hare been studied in much gr>'ater detail, na they have also in Canada. While, so it seems to us, tlie methods will be 
rtry diflerent (when operating fp<ia an aerial position) from those which h&ve been emplc.ved with the camera on the earth, it 
may, nevertheless, be of value to raeord the following survey of the method.? employed in Canada, which are described in a 
recent iarae of the ** Oeograpliical Review." It may be hoped that in the future tlie Science of photogrammetry, or 
surveying with aid of photography, will enter a|K>n a new era of usefulness, and will find its application in the mapping of 
still unrecorded portions of our p>ssesaionK overseas. — Eds. " liJ.'' , 



The aecnrate snrvegr of broken and loHy mountains is a task as 
difCru It as tlia geographic result* af' ' ing. The methods 

>^i|j|iyed have varied with avail il' nation*, the limi- 

i.t;:"ii< f ' r and ill- and the ohnrncter of 

the rrliff. tary engiii . . j. numlirr of European 

ruuntries, netably Italy and Auitria in iheir Alpine dnm.tinK, 



have don* admirable pioneer « 
tor nearly forty years,* the ; 
brv>ught to a high state of |>< 
fifteen yean. The followioK '<' 
the method and - 
that have bafleil i 
• >f the rough land* <d the western < 
In Wc«t<-m Canada there are U' 
varying in elevation from low n> 
mountain ranges n<<wig leti to el<A<i. 



A 'though in practical use 
till- niethixi has been 
.; the last ten or 
I analysis both of 
' and rlimate 
• •• the survey 
1 was liegun. 
•f broken country 
iills to snow -clad 
.1- .lid f«'*t above sea- 



level. Tl>e mapping of »uch country offer* many difficulties. 
Ordinary matbcNb ^f survey are impoasibl'*, except for very 
limited area*, and almoat pniliibitive owing to excessive cost. 

In order to meet these difficullies. the methiKl of photo- 

(CTn(>hK- ^tjrrrring was adc^pled, in the year 1886, by Dr. E. 

I' 'r-fi«neral of Dominion Lands. In that year an 

of thv Rocky Nt'iiintaiaa along the main line 

PariGr Railway wiix inaugurate*!. Since then 

. , " ....,...< meth'id has Itet-n used in many localities. 

l'liot,..;r.»phic surveying may Ix- ii^ed in any class of country 
whTe thf '■ 
appear cUm 
best adapUiU :•• ru.- 
ranges of Bnti«h •'. 
season dur'' 
i» short, an ! 
winds, storms, clouds. 



simplest possible form. In this respect they show a marked 
cmtrnst to the complicated designs of most European instru- 
ments. 

The camera consistsof an oblong' metal box, open at One 
end and fitted into a strong outer wooden case. The metal box 
carries the len* and two sets of cross-levels which may be rend 
through ii]>enings in the outer case. Inside the box there .ar» 
two sets of diaphragniK. and a shade is placed over the lens^- 
when a plate is exposed, in order to eliminate all superfluous' 
light. The instrument stands on a three-lcrew base, ideiitiral 
wilh that of the Iraiisil, so that the same tripod may be used 
for botli. The camera may be used with the long side either 
horizontal or vertical. In the horizontal position the lens 
has a field of about fifty-one degrees and in the vertical of 
about thirty-six degrees. The extent of the field is shown by- 
lines rule<l on the case. The size of the plates is 43 x 5^ inches; 
The carrying cose is made to hold the camera and twelve single 
plate holders. The total weight of the cas*' with the camera 
and twelve plates is about twenty pounds. 

The transit is a liglit instrument of the ordinary pattern, 
made by Troughton and Simms, London, with 3-inch horiiontal 
and vertical rircUs reading to minutes. The tripod has exten- 
sion legs, 3 ft. 4 inches long when extended, and 20 inches 
long when clo«ed. When in use a bag is suspended between 
the legs and filled with stones, and the legs and bag are further 
blwked with stones so that it is rigid in any wind. For 



hie feat4jre« ..re suRicientty markwl t«fc4_|M»e*ing, the head is taken off and placed in the transit box, 

— L.. • L in... .1 I ;_ U w -J -?3(W.I*.U.. I «-„ ■.lnf.A/1 in a d*nnvnfi /«nftp r^p*iif^^lPl^ tO hold thft 



photoifraphs The methiol is, however 

IS the high mountain 

rn Alberta. Here the 

iiis.'k >« accomplished with safety 

■« nrr often unfavourable. High 

and ei- 1 are the rule, so that 



work most often Ije done hum- 
On Canadian phutn^rapbic « 
are a camera and a small tran«i 



iiider great difftculty. 
'^^entisl instruments 



Il BMJ !>• o< I'tant t» nou Ihst oss ol t)>« •artist (ui 
k*W.J«rtsalahisnTnee(tb«<>Ml* ol Us\i 
M Iks liikfwi XtMsH In U»TC, n«iinaM« 



.i".a: 



C«tb«<>Ml* ol Uskhcl diinni llatilfaai'i 
A« Msr nrrUy, p. )*9 and 



■\rKil'the legs are jilaced in a canvas case designed to hold the 
l»«x and the legs. The canvas case is fitted with shoulder straps 
for earning. The total weight of the instrument complete is 
slxiut fifteen pounds. 

Owing to the excessive contrasts of Alpine scenery, ranging 
from snow in sunlight to deep and heavily timbered valleys 
in shadow, it would be impossible to get good photographs 
with an ordinary camera and lens. Moreover, there is always 
a certain amount of diffused light which tends to obscure the 
distant details. The remedy Tor the former is a plate having 
I great latitude of exposure, and for the latter an orthochromalic 
plate with a yellow screen. In the last few years the Cramer 



THE BRTTIBH JOURNAL OF PHOTOGRAPHY. 



[January 4, 1918. 



" Slow Isoohi'amatic " has been the plate principally used on 
Canadian sur\-ej-s. The Seed " L Ortho " has also given good 
• results. In the beginning of the season of 1915, the Canadian 
cameras were fitted witli Tessar lenses and Wratten and Wain- 
wright "G" filters. Along with these, Wratten and Wain- 
wright " Panchromatic Plates" were used and gave satisfactory 
results. 

Wlien in the field, it is important to select those points 
which give the best views of the surrounding country. This 
does not mean that the highest {leaks are always the best. In 
photf)graphs taken from a very high peak, the surrounding 
country often appears dwai-fed, and the details do not show up 
as well as those taken from a more moderate elevation. It 
must also be rememl)ered that the higher the ])eak, the longer 
the ascent is likely to t«ke, and the greater the likelihood of 
encountering sudden storms. Frequently very useful \-iews 
may bo obtained with little trouble from points of conijiara- 
tively low altitude. 

It is customary to take enougli vie^vs from each j)eak to 
cover the complete circuit of the horizon. This means very 
little extra work for the surveyor in the field, and the extri 
views ai-e often of assistance in the office. It seldom happens, 
however, that all the views can be taken fixnn a single jxjint. 
Usually one or more camera stations are required on different 
pa its of the peak. As a rule these may be located by reading 
angles on them from the central point and measuring the dis- 
tance with a light tape. Angles must ibe read on at least one 
well-defined point in each view, prefex-ably on two. The angle 
of elevation or depression should also be read on these jwints, 



ais it will serve to check the horizon line of the riow if there 
should be any trouble in the office. It must also be constantly 
remembered throughout all field work that all the country to 
be mapped must be seen from at least two jioints which subtend 
angles great enough to give satisfactory intersections and not 
too great to pertnit easy recognition of the same points as they 
appear in corresponding photographs, taken in pain, one from 
each station. 

For plotting purposes, bromide enllargements, approximately 
10 by 14 inches in size, are made from the negatires. To obtain 
satisfactory results, the enlarging must be very accurately 
done. This work is done at Ottawa with an enlarging camera 
made specially for the jrurpose. 

In the office the triangulatioii is plotted by ordinary methods, 
depending on the nature of the control. This may vary from 
a precise triangulation to a reconnaissance surrey, where the 
triangulation and the photography are carried on at the same 
time. Elevations of the stations and more prominent peaks 
are computed from the angles read in the field. Where neces- 
sary, corrections are made to allow for curvature and refraction. 

Views from different stations showing the same country are 
then selected. Si«fficient points are identified on each of two 
corresponding views, taken from the different stations, to show 
clearly the topography of the country. These points are then 
plotted on the jjlan and their elevations calculated from the 
photographs. Using these points as a guide, and with the 
photographs in front of him, the topographer is able to draw 
in his contours with an accuracy dependent chiefly on the 
number of points plotted and on the scale of his plan. 





c 

HI • ^^-M 


m 


^gff^^S^'^^f^^^^-^^jHH^s^^ 




- ■ ' ""^.. •■ 




i 




Fig. 1. 



Fit; 



!■ Igures I and 2. two partially overlappini; views of rugged topugiaphy in .J aspar Park iu the Canadian Rocky Mountains, taken from two different stations 

with a camen equipped for pbotoerapliic sutveying. The relation of the two views is shown on figure 3. Figure 1 is taken from the station marked B, and 

figure 2 from the station marked A on that figure. The numerals 1 to 5 represent the same objeoia in both views and correspond with the point* so 

numbered on figure 3. Tbi^ lulsd network in the foreground of figure 2 likewise corresponds wit'j the network of squares in figure 3. 



January 4, lOiaj 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



Fif;ure9 I and 2 represent views {i'>rn two stations shown as 
A ami B in Figure 3. On these viev~. points 1 to 5 have been ' 
identified to illustrate the inethiKl <4 plotting. The principal 
and horizon lines, whose positions have been determined during 
the season, are fir»t ruled on the view-. The traces of the prin- 
cipal line and of the picture plane f'>r each view are then laid 
down on the plan as shown. In Fifjiire 3, aa, bb, and a'a and 
b'b' representing these traces res|». lively for Figures 2 and 1. 
the distances of the identified jxiints fn.m the principal line are 
then taken off on a slip of pa|>er. a M-parate slip being used for 
each view. These slips are then placed on the traces of their 
respective views as shown by cc and r'c' in figure 3. The line of 
sight to any |>oint is then given by •Iniwing a straight line from 
the station to the projection of the iK>int as shown in the .slip. 
By inserting needles at \ and B. and using fine silk threads or 




Fig. 3. 

IMacnai to tllMlnte Um bm«1m4 of coiMitiwilac * mm Itoii two pl>DM«r>pble 
tWw>. fw nplaaaita*, m* Um Mxt. la ptmMm lM«iMaaM from J lo Mand 
iTom a lo *'»* I* Bsrfc (^Ml le Um local tangik 1 tb« vlawi aad Iba dlttaaess of 
;, f, 3, 4, i. •!•.. tnm A* sad ■•' itttt rU nXj %x% maim oiaal lo Um dMaam* of 
llMa* polaU Iron Um prtadial Ubm of Iba eana«|aodla( rtawi. 

hair* inftead of actually drawing lines on the plan fr<^ini each 
station, the intersections may be determined very rapidly. 

The elevations of the p<iinta are taken out by means of the 
instrument shown in Figure 4, which was originally deviseil by 
.Mr*srs. D. B. lV>wling ami H. Matheson, of the Canadian 
frrxXifi^al Surrey. The arms M and X are of brass. fa»tene<l 
rigidly together. i' and Q are sliding bars, moving »n the 
»rm M. R IS a swinging arm rev./lving arvund the centre O. 
I' and R. are made of transparent c«lluloid. and on It a fine 
line rr is ruled, radiating from llie centre O. The arm <^ 
came* a scile rorT»«p«mdii»g to the acale of the map. The 
inalrnmeni must lie made aorurat'-ly, so that when the line 



K D>' 



W..^ n.»y.J .> 

Haular.MaMc 

r. ▼. iVMii)...,, 

S51. 

H. M.WIIwm: To[ 
Irt (Ml.. Wllar, Mao 



' niliKet sra : 

'.la SanailBf. Iiirlwliac Ih* KlammU ul Ueicrlptlva 
OUawa.UM. 

-.-'-■^'Matbal* ai'd lastraaaaata. Appaa<ii> No. 10 ipp. 

s. Ooaat and OeoAaUe Samr lor Year (ndiiig 

-«. 

— — •irammla, laa aMtbodaa a« la dnalii ta|io- 

ivrVillan, Patia, 1901 and 190} 

,M >!• HlUamlUal dac OaUoJeaofnalinia, 

>ir><aBic*a aal RaiaaB," adil. h^ri ron 

h'.oaiklonidia dar malhcmatlicheii 
i.'Irila.MOS. 
- nda. Vol. X Cbapiar 16. Tth cdlL, 

.». .«j.. ,, Oaotr. JoorB., Vol. 11, 190«, pi>. iJ4- 

trie, aad Oaodaile H«rraThi(.Chapt«r 14. 



is over the Iin« s the reading of the scale will be constant 
when moved along the arm M. 

When using this instrument the centre (> is ^ilaced over 
the station, and the arm P is placed so that the edge coin- 
cides with the trace of the view, the line *= falling on the 
principal line. The instrument is then held in place by heavy 
pai)er-weights. The distances of the points alxive or below tlie 
horizon as shown on the view are taken off on a slip of paper. 
The slip is then placed on P, as shown in the diagram, and 
held in position by the clips pp. The scale is now set to read 
the elevation of the station when the line it is above s. To 
obtain the elevation of the point 5 the arm Q is imrved to 
the point plotted, and K is moved so that rr pass<i8 through 5, 
as shown on the slip. The elevation of the point "■ is now 
read directly oH the scale. To avoid mistakes the elevation «f 




X^B 



tt 




FUurt 4 

Fig. 4. 

Diacram of Inttniiiirnt uted io taking cat elevation 'of the point* a.s sliowii ia 
«(. i lifkgn of IJ. B. Dowling and H. Matheson, of the Cnnadian lieoloijiciil 

-fiiirveyi. 

each point is taken from the two views and the me^tn of the 
two elevations is used. 

Relatively toiKigraphir features such as swamps, lakes, and 
rivers with comparatively small fall are plotted by means of 
the per»l»ectometer. This consists of the per8i)ective of a 
series of S({uareB drawn on glass, having the <listance line equal 
to the focal length .f the photograph. The pixjjection of the 
sijiiares is laid down on theiilan, the perspectometer is placed 
in its proper position on the photograph, and the ouflints 
drawn in square by square. This methinl is illustrafetl in 
figures 2 and 3. 

The accuracy of a photographic map depends first of all on 
the pi-ecision of the triangulation. After that, it in dependent 
on the numU'r of camera stations and on the scale of the plan. 
H^ffJ w-ale ,.r contour interval may lie used. These will lie 
^Htennined by the purixwe for which the map is i-equired. For 
general purjioses, the writer cmisideis a contour interval "f 
1(X) leet and a scale of 1 :40.000 the most convenient lor a 
large plan. The pieoi»i<in is that of a good plane-table survey, 
but with the advantage that more points are plotted, and the 
contouring is done by the surveyor in the office, with the views 
from the different stations liefore him to which he <.aii refer 
alternately, while with a plane table this simultaneous, <-oiii- 
parison is entirely wanting. 

The most tedious and tiresome part of the work is plotliug 
the iwints and drawing the cont.mrs. The office work requires 
at least twice as long as the field work. This is not a defect, 



fHE iiuTisH jomttiii'^&i^ 'i^Hb^OGtSXpffY.''". 



[ januaify '4, 191^. 



but one of the greatest advantages of the method, for the field 
work, which is most expensive, requires ninch leas time than 
when an/ other method is used. 

A party of seven can wurk to the best advantage under most 
circumstanceQ. The party consists of the surveyor, his 
assistant, and five men, two of wliom should be expert packers, 
if pack horses are used. With two sets of instruments, the 
surveyor and assistant surveyor, each accompanied by two men, 
are free to work in the same <ii- different localities, the cook 
being left in charge of a main camp at .some central point. 
Except on long or dangerous trips, one man is enough to accom- 
pany the surveyor when actually climbing. If in a country 
unusually difficult of access, extra help may be atlvisable. 

As regards the cost of the work, it is impossible to give any 
accurate estimate. The cost dei>ends, in the fir^t place, on the 
nature and accessibility of the country, and, in the second place, 
on the class of work required. Much also depends on the 
season, as more or less time is always lost through smoky, 
cloudy, or rainy weather. The approximate cost of the writer's 
survey of the Crowsnest Forest Reserve in the years 1913-14 
was $9.50 per square mile. This may be considered a fair 
average. - ; •• 

The fdllowing is a list of the principal photographic surveys 
made in Canada. The areas given are only approximate, par- 
ticularly in the case of the earlier surveys. 



tiooftlit;^ 



Main range of the Rocky Moantains 
adjacent to Canadian Pacific Railway. . 

Colombia River Valley from Revelstoke 
to Arrowhead 

Alberta foothills south of Calgary 

Crowsnest coal area, near Cron»nest 
Pass. B.C 

Selkirk Mountains, adjacent to Canadian 
Pacific Railway, from Beavermouth to 
Revelstoke , . . 

Rocky Mountains, adjace'ntto Canadian ] 

Pacific Railway, from Mt. Castle .- 

; to Baa vermouth i 

Kooky Mountains, Robson district, north 

^of Yellowhead Pass 

9ooky Mountains, BanfE-Windermere 

■;?roadfrQm Vermilion Pass to the junc- 
tion of the Kootenay and Vermilion 

Rivers 

, Crowsnest Forest Reserve, South- 
western Alberta ; 

British Columbia— Alberta boundary .... 

Okanagan Iiake district, BritishColumbia 
Jasper Park adjacent to Grand Trunk 

Pacific Railway 

British Columbia— Alaska boundary .... 
Southern bouudarv of British Columbia. . 
Ynkon. Alaska Boun-lary (141st meridian) 
Thii ty-one-Mile Lske watershed, Quebec 
Reconnaissance surveys by the Qeological 

Survey I 



Area 

Surveyed 

in 8q. 

Miles. 


Tear. 


2,500 


1886—92 


600 
2,000 


1897 
1896—99 


550 


i9:o 


1,100 


1901-02 


2,200 


1903-06 


1,100 


1911 


500 


1913 


1,500 


1913-14 


1,500 


1913—15 


1,000 


1914-15 


800 
5,0C0 
1.200 
1,000 

200 


1915 

1893-1913 
1S03— 05 
1907—13 
1913 


9,000 


1904-15 



Suiveyor. 



J. J. McArthur 



J. J. McArthur 
A. O. Wheeler 



A. O. Wheeler 



A. O. Wheeler 

! A. O. Wheeltr 
I M. P. Bridgland 



A. O. Wheeler 



R. D. McCaw 

M. P. Bridgland 
( A. O. Wheeler 
I A. J. Campbell 

R. D. McCaw 

M. P. Bridgland 
Dr. W. F. King 
.J. J. McArthur 
J. 1 1. Crsig 
D. H, Nelles 



M. P. Bridgland. 



!t'Bos4» FHOroonAPHic Society. — The following memibers, out ol 
ten who nrnde application, liave been elected to the Fellow.ship : — ^F. 
Bridgen, J. Aubouxne Clarke, Bertram Cox, Mifes Jessie F. Harvey, 
A H. Liockingtom, E. W. Mellor, and A. E. Smith. 

. CoNTBOi, OF Lighting. — A reguJation (Ha.) made under tlie 
defence of the Realm Act states that the Ministry of Munitions 
inay, with a view to maantaiining or increasing the supply of light, 
hieat, or poiwer for the puirpoBe of the production, repair, or trans- 
port of war material, or any other work necessary for the success- 
ful proseou'tian of the war, by Order direct that lights of any 
specified cla«s or description ahaU be extingiuislied or their use 
restricted to suoh extent, between suoh hours, within such area. 
on suoh premises, aiid during such peinod as ina.y be specified in 
the Order, and if any pei-stai having oontrol of any light, or 
occupying, or having control of, or managing, or being in charge 
of premdae* in, on, or in coimection with which any light is used 
acts in eontravenihioin of any sudi Order, he shall be guilty of a 
summary •ffence against these regiilatixHifl. 



i^ 



-sST'' 



UEAI H OF MR. F. A. BRIDGE. 

One of the most fanifliair personalities in photographic circles has 
been removed by tlie death of Mr. F. A. Bridge at Bognor on 
Saturday laft, DecenvlxT 29. For some year or two past Mr. 
Bridge liad been in fivi!iiig health, tmd indeel had hardly ever shown 
his customary vigour and spirits since the death (A his wife some 
seven year-' ago. 

His business conuectrou w-itli pliotograpJiy was dhiefly that of 
a commercial and t€Khnical photograiplier, of which branch of work 
he had made a specially long before the days when " commercial 
photography" had bcxuiine a recognised (ieiixtrtment of the photo- 
graphic business. In this work he was something of a pioneer ia 




Uio extensive use whicli ho made of flashlight, in which connection 
his extejisivo series of photographs of the first London tuibc railways 
when in course of construction may be recalled. Although his 
teduiical work did not (igure largely in the public eye — he himself 
was habitually somewhat reticent in regaixl to it — he nevei-theless 
was certainly one of those who by their knowledge and skill have 
contributed to the estiibli.shment of pliotogra.phy as a docunienitaa-y 
agent for legal and commercial purposes. 

But Mr. Bridge nas more widely known in photographic cnrclea 
first as one ol the I'oiiiKlers and afterwards as secretary of tlie 
Pdiotographic Club aud still more as general secretaay, up to tihe 
time ot his death, of the Photograiphic Convention. His support of 
the Photographic Club was consistently accorded until the demise 
of tliat body. In the early days of the dry-plate process, the 
Club was the chief medium for the personal interchange of 
experience in regard to the tedhnicalities of all photograpliic pro- 
cesses. As, in course of time and with the deveilopment of gelatine 
emulsions, tlie making of dry-plates ceased to be a branch of 
amatem- work and became an industry, tlie club outlasted its sphere 
ot usefulness and almost all the members of its early days fell away 
from it. Mr. Bridge was almost tlie onJy one who supported it to 
the last and made the arrangiamenits for the transfer of most of its 
assets and effects to tho Royal Photographic Society. lu Mr. 



Januar>' 4- 19ia | 



THE BRITISH JOURNAL OF PHOfOGR.APK-Y. 



Bridge alio the Phuto«;rnp)uc Convent in of ike Cnited Kingdom 
found a necretary who for somethinit ke twenty years managed 
tho annual oommer meeking of that bridy a iub the utmost competence. 
No detail of the arrtngnineDtc for the v.~:t of two ur three hundred 
people to Scotland, the Weat of EngUii'i, or the Continent was to<i 
HnaU for him. With the change* in the circuni!<tance;i of photo- 
graphy, the character of the Convent: - * '<i;a likewise luide'r- 
weot a change from the day* of ita ' ut l>y the late J. 
Traffl Tagrkr. The technioBl eionu .; ht-came ir.ore or less 
subordinated to that of «if|bt-*eeing Imh evei>une wito has ever 
attended a Ooaventiun gathering wH' ' <- to the statenietit 
that a more uidefotigable, thorriugli. jiig *e(Tetar>' than 
.\fr. Bridge oould init have been ii.ii »r ima^ned. He had 
identified himaelf to ei<>«ely with the ' .inveotton, the last nie«ting 
of which waa held at Perth in July, 1914, that it i« difficult U> see 
how, after the mevittlile interru|>ti<iM < re«tcd by the war, it can 
■orvive hi* loM. 

In hu early daya Mr. Bridge wa« a sHngSr of some cnntiderahV 
diatinction. H our mrmory aerveo iic . '•rrectly, he wa« a member 
of the \Ve*tmiiiat«r .\bbry choir, atxl up to middle life pr.)i'ti>- 
■ional tnueical engiigemeiit* through'' ul the otaintry were (i«rt 
of hi* regular anivitie*. In phot«>(n-it'- c circle*, hi* hearty mannt- ' 
and til' 'leat with whii ' 'led oat anything »-;i cli 

he an i' -lo fur him a . •( frien^'a to whor. hi* 

departure -a ill Ue a real lo«e. 



HEATH OF MR \ IKMyTY. 

\\ I rf,i<'[ i.> rt' iird t'te dt'.tth < ii i i -tai^ Day of Mr. ('h.u-le« 
.VbUiit Booty, who w«a uiKk>ulite<U\ - k- •■» of photographic 
reprM* ntal* vea in tin* <-uiiiitry. and pp-i^l. i-raat a longer 
eonncetion with i>hi>ti graiihy titan a'lv of ) iiorariw. In 
year* gone i ' n Street, 
Obome'a, oi hou»fa. 
In that capiK •■ among 
phototpsphr andoncd 
thia or, bu.'au««t», becom- 
ing at: and C'>. At the 
time M hw death >w «a» uvcr 8i y««uj> «4 a^^'. 



Of hb penonat chani<«erMliei, one (Mr. J. \V. Hilder, t>f Croy 
donj to whom he wa* kiMtwn for many JNar* wrilra a* follow* : — 



I.»y* con- 

I, whicii 

iirii. He ured to 

r gave him onlv a 

■M. "H.- 

^v U> tlu- 

bith uf 

I to llie 

.• Mundei'fid 

\erv »JiIe l«> 



•• Mr. Booty wa* a i.'<i r 

ductad a atodm and i 
waa rary kargety patruuiMd by lim 1 
rabU that wtien liU'e more thao a U 
year to live owing lo proaoaarad ayn 
attaibated h'a raeoverjr and aMaimneKt 
oooluinaaa iokaUtion v4 the ryvnide ^ 
" tbe good old day* " of the wet r,.V 
Im* he latwnwl rMBariuibie act 
tiumarj at tmm and tkin^ He 
lawyer, and hia advice, aa very many wiU iv««li, hu* fnety give» 
to pholognaplMn in all part* of the rotintrr I m.\>i-lf hive luiJ 
eapariaaoa of hi* gu<Hi nature ii ta al*n a line 

■— tiiii acter, and >t waa au ei>^ to hi* recH i 

tion o( entrarta from tba cl a— i t pm-r- m ,icrtuUin»d 

to pcrlurm in the paaiat Brighloa. Tl y met Dickim 

on Iha ocoaaiona nf the novoiiai callii •wk*biip whu4i )■' 

(Booty'*) lather kept at Brighton. aiM -ittly made mont mi 

of the gmt iuipriaaioo whi<^ the ix-rMmakty uf the author uf 
Pickwick n«de upon him. Aa th« ousome of rtieumatiam he i<:rt 
hia voice, and for many year* had not »|>okMi above a loud whi*|M-r. 
He waa acruatnmeJ jokingly to i»y ham nympathetic fie<>p e 
were whan be railed upon them nnt-l to!d that it wa* hi> 
natural vaiee. To a rare fund of humour— he had aJway* a 
joke to Cftdt — ^'le added enreptioiial ,:ifta aa a raconteur, and wa5 
full of ancodnt«a and reminiMetirr* ilrawn from a very fall and 
varied expariance. With all there altm'-tive aide* to hi* charartrx 
he waa. neverthelem, ■ flr*t-TBte man of boaitiea*. He leaves a 
wdow, two MHia, aitd one grsnddan ifhter io mouni hi* lo**, and 
nil duidiUm receive a kindly memorial in the hmrlo of mn'iy 
nthera to wheai ha waa peraooally known." 



Usslstants' PoteSe 

— • 

A'o<e» Ay afjiistanfn siiitable for this column will he runMderfd 
and paid for on tfir first of the month followimj piihliintion. 

Repairing Leaky Book-Form Slides. 

Ir frifpieiitly happen.-^ tliiil the book-lnrni pattern of double liiiik 
slidu after some use (or it may be due to the .shrinkuge wlien 
improperly seas(/iie<i wood has been u.sed in construction cauewl by 
damp or ll>e action of the sun), admits light ;it the joint where tlie 
slide opens, with the result that the i>lates in the latter get foj^jed. 
Tl.ere is no rtMS(Hi when this lHr]>pei>s why th^ slide should be 
sci-ap|)ed as I have recently proved by n.iiking a very simple tiiough 
■satirfactury repair whioh nuide tJie slide as liglit-proof as wilten it 
wa* first in use. L'|K)u a careM test of tlie slide it was foauid 
that its ojuditioii was in every way satisfactory excfjJt at the ixiint 
mentioned above, but for some reason a certain looseaie.i's of fitting 
was evidejit liere, and I cast about foi- some means (vf preveaiting the 
light from eiiteriug by eiL«uring a tighter fit between the two halves 
when thu slide is closed. 

Tliia was done very erisily in the foHow.ing way. I prucure<l ."onie 
odd stripe of wash or "chamois leatlier " of the same leiigtli and 
width as tiie rebate of the slide. These were " seccotined '" .^11 
rouiMl tlie latter, care being taken to secure a ])erfectly wpiaie join 
«t tlie corners in ordt^r to prevent light enteriiig here. The elide 
«Ms tfljeii Closeil aiHl put aside for the adliesive to get thoroujtlily 
dry. I'ljoii testing, the slide was found to be in evti-j' way li^tlit- 
priK>f, and owing tii the elirticJty of the leatlier a much tijfhtta- fit 
",is stH-uied when the c«tihe» were in jMjsitiim. Tlie leatlier was 
c.irefully dead blackwl, ii.oro from the point of view of appe;ivance 
tii-ui foi aj;y otJier ivaaoii. U|>oii aiiotlitT .♦lide defective in tlio sniiie 
way I tried strips of black velvet, but this does not answer quite so 
well, a« it has not the iJa.st city of oluini'>is. .Any siidditr woitld be 
;{lad to gi^o or sell a lew scra|)8 of I'lianiois leather tor a few penc-'. 
Many pboti'Srapheis who have slides defective in tjiis w.ay while 
the dntwout jhuttisr* are pwfectly liyhl-proof, will welcome tjie 
aliov simple raetlnnl of rep^iiring wluit ai'e really niost expensive 
;kccc*M>i ie*. especially in large aiaes. — Expert. 



Paietit Reios. 



COMPLETE SPECIFICATIONS IcCEPTED. 
fkai* jfwei/Ieadon* art obl^mtbla, price 6d. each, poii net, jr.f% 

the Patmt Office, S5, Southampton Dui'.dings, Chnnccry Lane, 

Vondon, W.C. 
'!*^4 dita in bracktti u that of applicatioti in thii country , or 

abroad, ill (>K caae of patents granted under the liUernational 

Contention. 
lounK I'iioToo».*i-HV.— No. 110,993 (Jan 6, 1917).— The inven- 
tion consist* ill a method for ninkinj; a two-colour st reeii for 
use in the prodnctioii of plmto^raplis in colours. To one side 
of a thin sheet of a i olourless transparent material (gla«! or 
celluloid) a layer irf traiiapareiit colo.urerl particles is ajiplied. 
The particles are all of one colour— for example, red ; < onse- 
i|uently, they arrest the passage of .ill rays of li«ht e.xcej)! red 
rays. Tlic particles are sprmd in such manner that inteistices 
are left having appn>.\iinat«Jy the Hime area as the |><i.rt-:<lc!<. 
This layer of particles is then covered with a layer of c^ibiurless 

a«ntsh' for prote<-tion On this l.iyer, when dry. a layer of 

phutWhraphic emulsion seiuiitive to ureen iuid blue rays only, is 
spread. The emulsion is then e.xptised to while lijiht in such 
manner that the light passea Uirough the traitipiuent ba.se sup- 
porting the particles before affectin;; the emulsion. The result 
of this procedure is that the blue ami green i ays passing throiifrh 
tbe interstices affect the emulsion, and upon devel<(pniciil a 
black deposit is formed behind the interstices. A» the red 
particles arrest the passage of the blue and green rays, a««l the 
emulsion is only sciieitivo to such rays, no action occurs beltinn 
the red-coloured particle* and l^e photograiphic emuWion behiui' 
the particle* becomes transparent upon fixation. This W""" 
deposit behind the interstices is then changed by means of to- 



10 



If «i "Bit^sit jouRNii' 69 pkb^oMA^St. 



' fiinuxt/J^^^id^ 



- phoie^raftbic proceu wall known as tooimg, into one. of a Uue^. 

■'green colour — the complementary colour oi the red particles. 
(Tho method may be varied "by slainirbg the particles blue- 
^een and toning tJie black deposit behind the interstices a red 
colour. In tUjs case the^jjensitjve emulsion would be that known 
as panchromatk, 4iacl ifco':^igUr would be a red one, or white 
light passed, through a.X*3 filter. i" 

When thosctjeen Js mad« up (as it may bt 
lines, the app'.ioation to it of a pajichyoiifet.ic oniul.^ion may be 
omitted, and Uie screen may be brought into close contact with 
a surface of panchromatic emulsion during the exposure. Before 
development of the exposed panchromatic surface takes place, 
the screen is removed. The latter is placed, in its' relative posi- 
tion on the positive when development is completed. The posi- 
tive is made either by " reversing " the negative or printing 
separatelj. — Ernest Henry Tarlton. 43, East India Dock Road, 
Poplar, London, E. . 

trade Rames and marks. 

APPLICATIONS FOIl ItEdlSTIiATION . 
Bee in B. Design. — No. 380,210. Photographs. Fred Rendell 



Burnett, 108, Renficld Street, Glasgow, • photogiraipher. 
18. 1917. 



October 



jinalecta* 



HxtiacU from our weekl;/ anri monthly coittemporarle/s. 

Colours with Sulphide Toning. 

Ik theory (says a writer in "Photography and Focu.s " for 
January 2) the sulphide-toned bromide print should have the same 
oolour, whether the image has been converted into silver sulphide 
by means of tlie hy|xi-alum bath, often called the " direct method, 
or by bleaching ajid darkening — "the indirect method"; but in 
practice it is found that the direot n.ethod gives a colder bix>wn than 
is iiHuaJly obtained by ble.icliing, and tlie colour is to most tastes 
pileasanteo-. It does not seem to be generally known tliat although 
the hypo-alum bath is generally used hot, in. wdiicli case the toning :p 
complete in about twenty minutes, it is quite as effective cold if 
.sufficient time is given in whicili to do its work. About forty-eight 
hours in the cold will be found sufficient. The prints may be put 
into the solution face downwards and left, mcirely looking at tliem 
e\ory twelve hours or so to fte« that tliey are progressing 
satisfactoriJy. Thei* is no fear of over-toni.ivg, a^ aotioji ceases 
when the change is complete ; and if parts tone before the rest, it 
will be found that, given time enough, the slower parts catch up. 
Mid tha final colour is uniform. 



meetings of Societies* 

— • — 

MEETINGS OF SOCIETIES FOR NEXT WEEK. 

Monday, January 7. 

Bouth Lindon Phocographic Society. *' Carbon Demonstration." E. C Ridge. 
Dewsibury Photogr^iphio Hoc ety. Annual General Meet-ng. 

City of lioiidon and CrippleRate Piiotoijraphic Society. "Nooks and Corners 
of Old London." C. Foibes. 

Tuesday, January 8. 

Royal Photographic 8-ioiety. " Bromid<^ Printing." H. Essenhigh Co ke. 
BirminKham Photot;rap»iic Hociety. *' The Riviera.*' H. R, Howell. 
' Bkal^ bridge Ph:>tographiu and Scientiho Society. Lancashire and Cheshire 

Union Sli'les 
Hanlnv i»h 'tographio Society. Y.M.C.A. "Photography and Focus," 1917 Pnz' 

Blidi-s. 

Wednesday, January 9. 
Croydon Caranra Club. '■ Knlargint; on Bioi>itl.j Paper." A. F. CiUherine. 
PhotA-MicOKraihi'* Sooie y. "Monae Curi .sities of Crustacean Life." P. Martin- 

Dunoau F.H.M.8. 
Edinburgh Ph >togaphic Sooit-ty. Scottish Photographic Federation Pottrolio. 

Thursday, January 10. 
8t ckportPhotoBiraphic Society. "The A B C of Picture-Making." J. Hurst. 
Ijeigh Pho'o riiphio Mocie'y. fi. mid C. P Union Porifolios 
Hadfler-fleld Naturaliat and Ph^iogrAp .ic S iciey. " Photograpliy and Focus." 

Pr zc Siirlps- 
HuU Photographic Society. Oramophonr' Kiite-tainroent. 
Livrpo 1 Mnareur IMiotogr ipliic Assoc ution. " Scenes of Chinese Jjife." 

P. U. Roxby. 



Correspondence. 



•j^ Corespondents sliould neva; mrite on both sid^v/the paper. Nt 
;'■ notice is taken of commuTtu^t^ons unless the naims and addresself 

of tJie writers are given. ■■' ' ! 

',' We do not tmdertal;e ttspen^bility for tlie opini&na expre$sed bn 

our corresp-yndtnts. 1 

THE NEW ERA, LTD., AND THE P.P.A. ' 

; ■ .- To the Editors. ; 

Gemitlemen,— -Some months ago Mr. Archer Clarke, the origina/ 
promoter of the company now styled the New Era, Ltd., at our 
reciuest. wrote a letter appaariiig in the B.J. esiiecially disclaiming 
that his proppseid comp^ay had any Gonneotion with • th« 
P.P.A. As the prospevUis of the New Era, Ltd., contains a statej- 
nient as to the holding of the Preference shares by membert 
of the P.P.A.,. which migiBlt-lead to the conclusion tha,t the com- 
paaiy was lujt er.tirely dissociated from is, I am desired by my 
Council to point out that the fact that some of our members have 
subscribed for shares does not commit us in any way, as an associa. 
tion, to a councjlion witli the eonipaiiy, officiaJ or otherwise. Our 
attitude towards the company is precisely the same as towards every 
other commercial undertaking providing pho'tographic material — 
one of silrict i>eutiali'ty. — I am, etc., 

AlEXANDKR .M.iCKIK, 

Hon. Sec., the Professional Photographers' Association. 
December 27, 1917. 

ASSISTANTS' UNIONS. 
To the Editors. 

Gentlemen,— T/he recent article by "Thermit" in the " B.J." 

of November 9, on pihotoj;rapliclc labour aft<T the war, has aroused 
the inevitable sniggestiou of foi-miing an assistants' union, an^ 
reference has been nnde to the influence that could be exerted by 
a powerful ur.con. It seemis, however, to be forgotten that a 
jKjwerful union could hardly e.\ist in the case of photography. 
When employees are reckoned 'by thousands or 'tens of thousands 
whUe the employers can only be counted by tens, as in the case of 
caal-niincrs and co:il-niiiie owners, then a union of employees can 
be very powerful indeed ; but when, as in the case of photography, 
the [najcrity of employers l-.ave^only one m two employees, -a union 
is almost powerless, and can do next to nothing to benefit a single 
individuial. In fact, a single employee, :f only he has sufficient 
ability, Is as powerful by himself as any union, and when we find 
such an individual wlio is a first-class worker, but yet is underpaid 
and ovei-worked, it is pretty clear that he is himseli very largely 
ta blame. Wilth a little more pluck and independence he could, in 
the majority of casts, get all from his eniployeir that a union could 
get for liomi, and probably miuch more. With regard to the educa- 
tion of as.sdstants, it would also be well to remember that tlie war 
itselT Is now educating many in the most practical fashion. Under 
the most adverse and difficult conditions thousands are being com- 
pelled to turn out work of a very fairly hcgh technical standard. 
It is more prcbable tb.a.t there will be a glut rather than a dearth 
of first-class darkiuon. a..':£iiataT ts after the war; so this matter will 
be likely to rig'ht itself, while wagts wMl almost surely follow the 
same course ns in other ti'ades, and be higher tlian before the war. 
Drastic methods of reform tiliat are practically certain to lead to 
contention and trouble are,' we think, best left alone until their 
necessity is proved, and it does not seem to be at all well proved 
at present. — Yours faitlifuUy, Lux. 



THE SENSrrOMETHY OF PHOTOGRAPHIC PAPERS. 

To the Editors. 

Gentlemen, — Mr. Stinchfield's 'etter in your issue of December 14 
oont.ilns, fortunately for me, one inaccuracy. He suggests tliat in 
my review I applied the word " invalidated " to the whole of th« 
paper of Dr. Mees and his colleagues. As a matter of fact, tha 
wor3 does not occur at all in the review, but only in my Isist letter 



Januarv 4. 19ia! 



THE BRITISH JOURNAL OV PHOTOGRAPHY. 



11 



ja yoar Msoe of NoVonber 9, and thrrr it had refereiu-e uiily to " « 
fjavjcl deal td the siithor»' ooa<-Jtu>»iis a> to the ap{ilicati<>ii of thMr 
rooKa." Cleariy, then, my critiri«ni was directed a^a'iHst this 
^ipUoatMa and iM>t in any sense aKair-t the enperinientul work. 
Oa re-reading tbe review in the lifrht •'! Mr. 8tiiw4ifiel(l's letter. I 
find then ts a poMlbility of a miguiidt :>t«iHl.-ng of my intention. 
A/ter ibriefly referring to the ex]>ei''. mental -work and to the 
a<ith'V»' diaooaion of the result/', I «ai<l. "Hie value of the whole 
paper w, howerer, aeriou.*!y depredati'.l hy the neglet-t to take 
Mooant flf 41ie taet that n pa|»er :■ not iifeswrily intended to repro- 
joca a aagative. bui, ihix^i)^ a netpitivi- as intermediate >tage. to 
rapfodaoe the origioal." I -wa* thinking in this ionlenoe of the pur- 
nnaa of the paper «« a whole, whioii I waa certainly iwit alone in 
aaderatanding to be not merely the reo>!-<linK ot certain experimental 
r^nlta, bat At prov-sion of criteria 'liv which to jud|;e the quality 
ni printini; paper*. Thia purpote I oMi-idered, and still consider, 
-waa not achieved, ior the reaao.ia I -Imm- .ilrrady «tit«d, and the con- 
t^tion ie »lill further borne oat by I>r. M.-e»' admission of the iiece«- 
Miy for more work oa tiie general <iur>tiun of tone reproduction in 
poaiirres. 

Is a« far, howoMr. m the wiiien.- I fcave <|ii>ite<l m.-iy have 
•ppaared to be advOTvely critical ui t! <- experimental methods and 
reaaltofpTen in the paper. I have great p>aaarB now in amending it. 
I 4o not think *ny valuable porpoae vill ba gMned by a discussion 
•f fartlter deUil» of Mr. StinchfieM'* IrlUr.— Yours faithfully. 

II. V STiHR. 

36. Tfie Noiurr, Ilford. K. 



Commerclal$£e0al imelllflctice. 



Ij^al NomXK Xolice is civan Uiat liMiuunr* of the U. an<l R. 

Procesa Enftravii>]{ Compaay. Idflu't ' ' •ireSyiificate 

Idnnl«d, havu bran struck off the I >; ('onv|iMiies, 

and sra diiw>lved. 

NEW COMrANIES 

tsiDvit* SrCDlm*, Lti>. — This private ODlli|u>iiy was rrKi>tere<i on 
IVceraber 22, with a capital of £l«i " PA •».-,-, (5 " founders or 
pmfercnce " and 95 ordinary). 01' 'iipin. pbuivgra{>hic 

snd miniature artsts, dealers in |u -"-les. jeweiler*. 

pirtnrs {mnin niaken, art daalem, et< i • (encli witli 

<mt ordinary sharel are: — Ikfaria J. I ...^oiroft. Kani 

l->r<'iiK'li, HanU. ; Helen K. Tayl-nn 'ft, Karnbonjugh. 

Il»;tta. Manager: Helen D. T^iyluar. ■■ or founders' 

•ham are ef. titled t» a fixed cainul:ii dividend at 

SOO per cent. (>er annum, and each *...,. iirrs 15 vote* 

sgamst un^ lor «trh ordinary aharf. Registered otHr- 171a, 
if Inane MUcet, ».\\ 

TNiai.wriJ., Lrn.— This private compMiy was registered on 
nr<-enibf-r 22. with i .-at.it.il of £6.000 ■ f" 'i:ires. Ol.jwts : to 
...f|iiir<- Ou 1,1 ..111... .,f |<!i.-t<>icraf>her> ' arried un by R. 

'nnrlwtll wkI K.i in-f mi ( .. I.ld . ar iiur.^rij and Co.." at 21, 
Rri'lfc'.. r.,,,.l. St., ;^i,,n ,.. I',.,. .,i SU .m.^ Sttvet, l>M-liiiKt<qi. at 
Church .S{usr«-, W«l lI*rUe)«».|. ,ii 59. Newgate Stivrt, l)tshoi> 
.^orlIland. at 8Ba, Nart)iunil>-i'l.iii<l Strret. NVwi-astlf-oiiTnir. 
ami at 75, Linttiorpe Road. .MMiill..«iMvuch. Th>- subscribers 
(caA with one litAr) are:— R. TliiriweH, 36. Cnu>lR>uni« 
Tervw, iMocktoti-on Tte>. photn«R.|4i«r ; J. Thirlwell. 36. 
'•lima Tarraw, Stotrktoa-on-T^ -> . i>hutogra|iher ; V. T. 
' ' .Artr»wicke, Hartlsmi R(«d. St^sdtton-on Tem. director of 
■ -i( ' o.. Ud. The firH direct, r, afo:— R. Thirlwell, A. L. 
■» .1. Thiriwell an'f V. T. Nattras' (all permanent). Registrred 

21, Bridge RinhI. Htnckt<nun Ti-va. 

K .\ fnrnifAi. <'o. , Lrn. -'Hii* pri\-ate nnnfiany was 

r.,{i,l.r.v| .,„ |)„,mber 21, with a r;4|.ital of £1.000 in £1 sluirea. 

Oiijucts ; (nrfunM-ry diomiste, manuf.ictureri of and dealer* in 

l>rrf>ri«twy artielas, pi^amtU, phrt.igniphic goods, etc. The 

-'"»<» (aaoh with one (hare) are:— J. A. Ward. Westnow, 

»vr«y, aaka agaot; J. X. Nioolai, 88, Sinclair 

^••* Kmmiiglam, chamiA perfonwr. The first diretlor* 

"■■' -J. ti. Nknbi. J. A. Ward and K. .Sc1k*.I. S.licit.,r» : 

I-V^otis and J<4inBoii, 19, (trwl Winrh^lt* Street, E.C. 



N.. ! 

K.HM 

A 



jinsiDers to Corr espondents^ 

8PID0IAL NOTICE. 
In eemrquenee of general rfduced $upplia of paper, eu tht ruvU 
of proMbition ef the importation of much wood ptUp and frau, 
a imalUr ipaet wi ll he availakU until further notiet for rtpliei 
to corretpondtnti. 

Moraovtr, tat wiU oasiser 6y pott if etamped and addretitd enve- 

top* it snrloscd for reply i B-eent International Coupon, from 

raadert abroad . 
Tk* full quetiiont ond an»iper« ipjH he printed only in l*« laet of 

inquirie* of general interest. 
Quarie* to he anewered in the Friday'i " Jowmal " mu$t reaeh ue 

na< faier tAan Tueida f {potted Monday), and ihould he 

addrttttd to the BdHori. 



f. K. H. — We think yon can get matted tellu!oid. under tiie name 
of " Norwich film." from dealers in procew requisites, Biioh a.s 
(iriflins (Kemble Street, Kingsway) or Penrose's (109, Farriingdoii 
Road, E.C.). Failing these — we 'be'ieve Norwich, film comes from 
the U.S.A. — you should try Messrs. Rheinlauder. New Maildeu, 
Surrey. * 

M.ii K. — We are ><irr> »<■ cannot s:»y nnulh tli:i.t iii good of tlie 
roloncliing. Your tonWi seems fair ; but you ajipe^ir to have no ideji 
where to put the work. You have i:n:outJied out n««r]y .all the 
iriadation and left a very washed out effept. Withtnit havihig 
Keen a print from an uiireiouched nega'tive we should gucm that 
you had done too much work on it. 

TiSTin. — There is no Ixjok on the subject; the best particulars we 
can refer you to are c»nlaine<l in a catalogue which Meeam. 
Kallowfield, 146, Charing Cross Road, Loudon, W.C., issued— «nd, 
we believe, still icstie — dealing witJi multiple camenas, oolours, 
ruUcri'. nml apparatu.s for celluloid surfacing. You might also 
write tf Mes*rn. Rheinlauder, New iMakleu. Surrey, who have 
>ome specialties of ser\'iic in this bniiicli. 

.1. P. !S. — .'vi far as we know, there is no truth whatever in the 
statement. We hivi- heurd of such tlungs h|api>ening, h\A never 
in the circumstances such as those whicli you state. If th<' 
|>arties persist in re|>eating their insinuations, we should think 
that the address to them of » lawyer's letter pointing out that 
they are bringing tht-mselves within the law ,of libel should he 
sufficient to stop tlieru. Better to ;lo this tlwiii to indulge in any 
retaliation. 

H. T. — If \i>\\ iU>iri- to register simi>ly the aitistic copyright in tlie 
dr.tuing, then we would inform you tliat sucJi is no longei- 
iiei<.«ary under the preesiit Act. Ihe drawing or design becoones 
automstical'.y copyright fr<im the fact of it« creation. If. 
however, it is your idea that the drawing should be registeo-ed as 
;■. trade nuirk then thai is out of our province : you require to 
(ippiy to the Rei<ii.trar of Trade .Marks, 25, .Soutbajni>too Biiildin««, 
( Ibuirery I^ane, Uoiidon, W.C.2. 

llr-STo.— We are afraid there is nothing now to lie done. It is a 
Uioiisand pities that y«i did not make the purchase through our 
depuait sy»tcm which is a perfect safeguard against disappojntmeiifts 
__Aa^ nnsatisfactory dealings sucJi as yours apjjears to l>e. The 
•»nK ^ing vju on do is to have a solicitor write to tihc |>e«|)le 
threatening then, with action for misi-epreseiitation, but (uiles.s 
yini are prep»re<l to go to the full leiigtli of tivking out a mimmiwns 
in the County Court we should imagine that simply a threat of 
(irureedings will not be very nnicli good. 

LiNlKr; WoonES Di.sHES. — ^I have seen mentioned in the "B.J. " a 
inateriu! for lining wooden dishes to render ithem sni'.able for 
fi.\ing and washing prints. Would you kindily tell me the name 
of the material and where obtainab'.e? — C. R. 

We think you must refer to the material called " Rirberoid." 
which you can perhaps ]iersuade a local firm of house decorators 
to supply you with, i»r (Mjseiibly they could order a supply for you 



12 



TEE BRITISH JOURNAL OF PHOTOGRAPHY. 



[January 4, 1818. 



from the mAkers «t the Brimsdown Works, Essex ; but we believe 
the materiaJ is not supplied direct except to those more or less in 
the trade. 

B.— If you mean lor the making of side-lights in dark-rooms, a very 
good substitute is ihe gelatine slieets soild by Messrs. Brodie and 
MiddleUm, 79, long Acre, London, W.C. These can be made up 
with tisiwe paper, if neceseary, to form semi-transparent safe- 
light«. See ajtide in last week'.s " B.J." 

W. E. A.— It would be useless to give you a dry-plate emulsion 
formula ■without detailed directions (which would be too long for 
this oohimn) for compounding it, washing, heating, etc. The best 
advice we ca» give you is to get one of the laiger handbooks on 
photography, each as Abney's "Instruction in Photography," 
published by Mesers. Eiffe, price 7s. 6d., from which you will be 
able to gather how to compound and prepare an emulsion for a 
plate of moderate speed. 

The Kit-C.\t Sizb.— At an art olub some time a/go, and in the news^ 
papers quite reoesntly, mention was made of the " Kit-Cat " size 
and style of portraiture. Can you explain it?^B. W. 

Kit-Cat portraita are three-quarter lengths, and meaeure 
36 ins. Iby 28 ins. The size has not yet been recognised in iphoto- 
graphy, !bnt it i» fairly well 'known to artists of the brush. The 
size and style originated in the year 1703, when a club was founded 
at a mutton-pie house near Temple Bar, kept iby one Christojxher 
Cat, whoee pien were humorously termed "Kit-Oats." The olub 
was supported by many (forty -three) famous men of the period, 
each of whom presented to the founder, Jacob Tonson, a portrait 
painted in a special way and of a special size by Sir Godfrey 
Kneller. Hence the origin and size known even to-day as Kit-Cat. 
TJiis interesting series of portraits still existe, it (being last heard 
of at Bayfordbiiry, near Hertford. 

History of Photography.— We shall be glad if you will kindly 
tell us if you know of any work dealing with the history of photo- 
graphy, or, if not, where we could get such information to enable 
a student to prepare a short jxiper on this subject to read before 
a literary and debating society at a public school. — A. H. 

The best book for your friend is "Photography of To-day," 
pvibKshed hy the Seeley Service Coanpany, or obtainalble from our 
own publishers, price 6s. 5d., post free. We would refer you also 
to the issue of the " B.J. "of June 19, 1914, which contains quite 
a complete history of photography, and ds still dbtainable from 
the publishers, price 4id. 

Costume. — 1. It is a matter for the ruling of the Registrar of 
business names, but we sliould cei-tainly say that coupons would 
ccme luider the same category as receipts and will require to bear 
your real name as well as that under which you trade. 2. A very 
good little booklet on the Business Names Act is issued by Messi-s. 
Jordan, kvw stationers. Chancery Lane, W.C, price 6d. 3. We 
belier\-e the niiniroaran fee for the registration of a company is £2, 
which iricludes oonipanies up to a cajjital of £2,000, but thei-e are 
other inland revenue fees, and the best thing you can do is to 
apply to the Secielary of Inland Revenue, Companies Registration 
Department, Somerset House, Strand, W.C. 2. 

Coi'YEiGHT. — My son, his wife and baby, had their x^botographs 
taken by a photographer, and paid for them at the rate of £6 6s. 
per dozen. Is the copyright my son's or the photographer's ? Can 
I copy them for making enlargements, postcards, etc., witliout 
infringing the copyright, if the photographer's? — F. L. T. 

If your son gave the order to tlie photographer in the ordinary 
way, and was not solicited by the photographer to come to the 
studio and to he photographed iwithout liability for payment if, 

■ for example, he did not like the photographs, then the copyright 
i.« your eon's, aind you can do exactly what you like with the 
jjhotographs in the way of haviag them copied, enlarged, etc. 

X. B. E. — ^Although we are not lawyers, we certainly think that 
the insistence on all lette's being re-addressed to th.; late pro- 
prietor — you do not say whether l.e traded under his own name or 
not — is certainly hn act which constitutes a possiV.e diversion of 
part of the business of the studio from yourself. Whether it is so 
■n fact is a matter which we think wouid require to be proved 
before it would he possible to take successful action aga'n^it him. 
Surely you must )"av« ^ou>id iiL^itances where people had irrst 
written about an order and then afterwards had called person- 



alty, you having then discovered that the letter had gone on te 
the former proprietor. One case of this kind would obTiously pot 
yr>u in a strong position to restrain the formei- proprietor from 
continuing the practice. 

C. S. — 1. Certainly it is remai-kable what can be done in the way of 
short exposures with a plate of the very slow speed of the 
Wratten Process panchromatic, particularly, in our experience, 
when using very small sizes of plates in a hand camera of vest- 
pocket size; but as you do not specify any particular apparatus 
for which you are using the plates, we should hesitate to say that 
you wiiM benefit materially by substitittinie these slower plates for 
those you are at present using. 2. Certainly some ol the cheapei- 
between-lens Gutters are liable to give different exposures, even 
while remaining set at the same speed marking. We do not think 
you can take it because you have the chart in question that it 
is a guarantee of the constancy of the exposures at any giveai 
speed marking. We have not had enough practical experience of 
the slmtter you mention to be able to say w^hether it ia perfectly 
satisfactory in these two respects. 3. Roll film cam he fuxthei 
colour-sensitised, but we have no formula that we can give yon. 
Extra sensitising of this kind is confined practically to cinemato- 
graph film, which is used for the various colour rsinematography 
processes, for which it is extra-colour. 

Copyright. — Can you tell me whether it is now neoeasary to mark 
photographs " copyright "? I have a lot of negatives which were 
registered under the old Act, and am issuing postcards of some of 
them. Does the proviso in the old Act as regards marking them 
copyright apply equally under the new Act ? I notice in a lot of 
the photograplis that one sees about that there is no mention of 
copyright, but presume that this is because thev have been made 
since the new Act came into force. Shall be grateful for any light 
you can throw upon this matter.— Amos Tibbbtt. 

You are wrong in saying that under the old Act it was neceseaiy 
to mark photographs "copyright." There was no such formality 
ordered by the old Act, nor is it necessary to use the mark " copy- 
right " for photographs which have secured copyright under the 
1911 Act. But there is now a very good reason indeed for so 
marking every photograph which is issued either as a single pnnt 
or in number as postcards. This is that the 1911 Act contains a 
clause which in a measure exempts infringers who can show that 
they have no reason for supposing that copyright existed in the 
work (photographs, etc.) which they had ^infringed. Obviously 
the marking of a photograph "copyright" is some consdderable 
defence against advantage being taken of this provision. 



f te %nthh Immtal of f botograpbg. 

The Oldest Photographic Journal in the World. 
PUBLISHED EVERY FRIDAY. Established 1854. PRICE TWOPENCE. 



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24, Wellington Street, London, W.C 2. 

IMPORTANT NOTICE TO READERS.— Vnlil further notice 
agents will supply tJie " B. J." to order only, as " returns " are no 
loi\ger accepted by t}ie publishers. This step has become necessary 
owing to tlie further restrictions imposed by the Government on the 
importatioti of paper and paper-making materials and of tlie con- 
sequent shortage of supplies. It is therefore necessary in order, to 
ensure the regular delivery of tlie " B. J." each week to place a« 
order definitely with a dealer, newsagent or book-stall clerk, er to 
send a subsciiption to the publisliers. 



THE BRITISH 



JOURNAL OP PHOTOGEAPHT. 



No. 3010. Vol. LXV. 



FRIDAY, J.\NUAiiY 11, 191y. 



Phice Twopknce. 



Contcnrs. 



ftmm 

Kl CATUBkA U 

S' it<i' c Axn Vmumcm n nu 

C'l -"' or Paum 14 

Tml Rut It PavrooBAmic 

B'KltTl IS 

Tn Pit*T>oa Of Puvra. B; 

A. W. Warwick 16 

Tim HoTAt PaoTai.BAraic 

Sotimr 17 

DMTa or Mm OaeaaB T. Watr- 

ncLS 1 

U 



CuMMKaCIAI. J>» LfOAl IXTSI^ 




TIM PT B fm<u ii«l PholecnpbM.- 
Aiiirt M loa ud Um Mm En. 
I.til. — Backed TnasparanriM 

Hackiof-opTnuitparenciM 
AisiataaM' t'nlooi Co^prra 
live insuiiiaklnf: Th« New 
Kr*. I<hl 

AaawaaiioOoa 



"Hu Summmrif of eomUnU nhieh utiuillg oecupitt the lou-tr Half 
•1 titU arfMam mil b» tonnd at the foot of the page octrUal and 
wilt MutiHtie to be placed thort wkiht iIm regular pontion it re<i*irtd 
for Wilut\ reiatimf to Urn fortheaming " B.J. Almatuu." 



Yk All by ye*r, since the dimly distant date of August, 1914, 
it has been iMceasary to adjust the |>r«>ductioii of tiie 
AlmaiuM; in aoeordance with the lireumstanrea of the time. 
A year md we iasued only 20,000 Almanacs: thev were all 
speedily bought. This year only 15,000 will be available, 
and at the Uni<* or writing pretty nearly the full number 
has been ordered by tlie trade distribution finns. The 
balance repreeent« the supply (small) from which you, eood 
reader, and othen who, like you, have not yet pUoea an 
order, may secure a copy. 

L«t there be no mistake, a book nich as the Almanac, 
particularly at it« now increased prices of Is. 6<1. and 
2s. 6d., IS not ordered by dealerH for chance Mie. There is 
probftbly searoeiy a copy amon^ the thousands already 
ordered whieh is not, in fact, earmarked for stmieUxly or 
other: that ia to say, imiuded in our publisher)) larjje 
totals because somebody in Builtli Wells or Bri<ibane months 
•go told his dealer to secure it. It is for thi.t reason that 
we must counsel the reader t<i (>la<e a definite order if he 
wishes to make sore of the 1918 volume. We have urged 
this f>rec*ation in past years because of many instances of 
its neceasity ; it ia even more needed in the present instance. 
wiien the edition has, perforce, been reduced by a further 
1h per rent. 

The editorial article in the forthcoming issue deal:) with 
Negative -making — development by tank and time: fixing: 
fixing-hardeninf^: waxhini; «nd hypo-eliminators; stain- 
removers and drying — largely in reference to present-day 
conditions, ('in unutanoes of the time, such as labour 
aii'l materiaU. have in a measure created new conditionn 
*iii.-h mu.it have their counterpart in photographers' 
nieilifKlg, The Almanac article is to be studied in this 
«-iinri.-.f 'on uow BP'I for flit* future. 



Economy in 
Hypo. 



EX CATHEDRA. 
As many of our readers have doubt- 
les.s learnt for themselves during the 
past tew weeks there is just now a shortage in this country 
of hyposulphite of sotia solely in consequence of the large 
quantities of this chemical requisitioned for military 
purposes. HyjK), it may be recalled, is a mild antiseptic 
which hqs specific u.ses in this capacity and further is an 
imi>ortant constituent of the anti-gas masks with which 
our soldiers protect themselves from the Germans. There 
is, however, no reason to believe that the shortage will be 
of more than short duration, yet at the same time it 
behoves every pliotographer in his own interest no less 
than ill that of his colleagues throughout the country, to 
observe whatever economy in hypo is possible at the 
present juncture. In practice such economy will consist 
not so mucli in keeping baths in use up to the point of 
exhaustion but in maintaining a reasonable temperature — 
not below 60 degs. F. — of the fixing baths and in setting 
aside baths which have been used for the fixation of prints 
for after employment for ]>1ates where their progress to- 
wards a state of exhaustion can be readily followed. 

» « * / 

White Baofc- Every now and again we raceive appli- 
tfpounds. oatious for a formula for a mixture 

which can be applied to a background so as to secure the 
practically o|Nique deposit on tlie negative, which is the 
desideratum for sketch jwrtraits. It mav, therefore, be 
said that beyond adding a little blue to the ordinary 
white di!<tem|>er nothing can be done in this direction 
which is of any material advantage. The intensity of 
deposit in the negative must be secured almost entirely 
by correct illumination. Very often tJie background is so 
lighted that if it were made of frewhly fallen snow it 
would still ])hototgraph as grey in the negative. There 
seems often to be a failure to realise that the soft lighting 
which the sitter required to receive for the making of a 
«ketch portrait must not extend also to the background. 
To get one tyyie of lighting in one place and another in 
another it is necessary to place the background further 
"~awiy/, and by adju.ftment of blinds (in a daylight studio) 
or of lamps (in ene where artifi«ial light is employed) to 
.sei-ure much more intense lighting on the ground itself. 
Often enough in a daylight irtndio the photographer is 
handicapped by the fact that his glazing does not extend 
badt to the level where the background is usually placed. 
The conditions then are exactly the opposite ot those 
which are favourable to the lightin? of sitter and ground 
for nketch work. The remedy, obviously, is to bring the 
background several feet forward, so as to receive ample 
illumination and to supplement the subduing effect of 
side blinds ujx)!! the sitter bv means uf head-screens or 
the like. 



14 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



fJaiuiarv 11, 1918. 



Buried We have many pLotographrc exhibi- 

Treaaupe*. tions, in every one of which there are at 

least a tew pictures which sliould find a more extendea 
market than that offered by the exhibition itself. A 
correspondent in the colonies recently inquired where he 
could purchase duplicat«s of certain photographs by well- 
known exhibitors, and all that could be done was to 
refer him to the artists themselves. Surely, it would 
seem that the time has come when pictures by photo- 
graphy should take their jilaoes in the picture-sellers' 
windows as they did in the earlier days of the art. Theii 
evanescent character caused their downfall in those days, 
but now platinum, carbon, and Bromoil can challenge 
engravings and drawings on the score of permanence the 
question becomes one of artistic merit alone. The fact 
that only limited numbers could be produced if the 
exhibition standard is to be maintained would enhance 
the value of the prints and create a demand among 
serious collectors. As it is many art-lovers have no idea 
of the possibilities of modern photography, except that 
gained from the illustrated papers or the portraitist 
show case. They have never visited a photographic ex- 
hibition, they have a quite erroneous notion that the 
Salon is the refuge of the Cubists and Futurists of photo- 
graphy, and in extreme cases that photographs are still 
shiny things that fade. There is an opportunity- for an 
enterprising print-seller to undeceive them ! 



White Image One of the things the supply of which. 
Developer. apparently, has been more or less com- 

pletely cut off by the war, is the developing solution which 
is employed for the making of the direct positives on 
ferrotyi>e plates, which are still a form of street-corner 
photography, which continues to have its vogue. The 
characteristic of this developer is that the image which 
it yields is relatively white instead of black, or, at any 
rate, is of a degree of whiteness which is sufficient for 
purposes of contrast against the black of tlie ferroty]>e 
plate. A year or two ago the Vanguard Company, which 
])Teviously marketed a developing solution of this kind, 
published the formula for it in our columns, and it may, 
therefore, be of service to some if we again reproduce it. 
It is: — A. Soda sulphite, dry, 3A ozs. ; water, hot, to 
make 16 ozs. "While hot add hydroquinone '120 grains. 
B. Ammonium chloride, 3| ozs.; ammonium bromide, 40 
grains; hot water, 16 ozs. Solution B is added to solu- 
tion A, addition then made of 2 ozs. fluid of strongest 
liquor ammonia and the whole then filtered. This mix- 
ture then forms the working developing solution, which 
must not be further diluted with water. It can be used 



over and over again until more or less exhausted, and 
in fact works better after a time than when freshly mixed. 
The plates should be fixed in an ordinary clean hypo bath. 



SCIENCE AND PRACTICE IN THE FIXING OF 
PRINTS. 

The further paper by Mr. A. W. Warwick, which we 
print upon another page, continues, as will be seen, the 
record of this very capable experimenter's work on the 
process of fixation — this time in the process of fixing 
prints. Broadly speaking, Mr. Warwick's results are on 
all fours with those on the fixation of plates which we pub- 
lished in a recent issue. Their diflerence chiefly lies in 
the fact that, inasmuch as the emulsion coating on printing 
papers contains a very much smaller quantity of silver 
bromide fixing can take place — we say ran — in a much 
shorter time on this account, and also for the further reason 
that the fixing solution gains access to the emulsion layer 
both from the front and through the more or less porous 
paper support. Thus measurements made of the action 
of the fixing bath at intervals first of five seconds, then of 
ten, thirty, and sixty seconds, showed that the quantity 
of silver bromide usiially present in development papers 
is rendered completely soluble in from 15 to 20 seconds. 
Mr. Warwick confirmed this observation by the delicate 
sulphide test, according to which after fixing for 15 or 20 
seconds, and then washing in several changes, the paper 
was found to give no dark spot when touched with a glass 
rod moistened with sulphide solution. Similarly, his 
experiments, as he has conducted them, show that prac- 
tically the whole of the silver bromide is extracted from 
development papers by immersion in two successive 10 per 
cent, baths of hypo for li minute in each. 

On the basis of these tests we have the recommendation 
from Mr. Warwick that in fixing bromide and gaslight 
prints in a 10 per cent, hypo bath the time of immersion 
need not be for more than five minutes, and that ten 
minutes may be taken as an extreme length of time. It is 
suggested, in view of the fact that a sheet of development 
paper can be fully fixed by immersion for 15 or 20 seconds 
in a 20 per cent, hypo bath, that therefore makers' instruc- 
tions to fix for as long as 15 or 20 minutes in a bath of this 
strength are ludicrously beside the mark. Here it is neces- 
sary to make the most emphatic distinction. Mr. Warwick, 
as his paper shows, operates on a single sheet of bromide 
or gaslight paper, and gives it his full attention in the way 
of promoting the full action of the hypo solution upon 
it. Such conditions are as far removed as they well can be 
from those which prevail in the fixing of prints as prac- 
tised by either the amateur or professional photographer. 



SUMMARY. 

The presidential laddress to the Royal Photographic Society, wliich 
we print upon another ]>age, took the form of a review" of the 
recently i)a8t history of the Society in i-eference to its anciently 
professed aim of existing "for the advancement of ])hotography." 
The address cites instances in which it i.s alleged that opportuni- 
ties for pursuing this aim liave l>eeii missed or neglected or have 
not been sought. On the other hand, putting aside this lemissness 
in the jrast, it cannot ibe said that the address contains anything in 
the way of definitely constructive policy for the future. The 
instances which the president gave of the valuable photographic 
work which is 'being carried out by the photographic branch of the 
Royal Naval Air Ser\-icc will be read with interest. (P. 17.) 

In an editorial article we have something to say on the R.P.S. 
presidential address, paaticularly in respect to the fact that it is 
scarcely fair in classing equally the last ten or fifteen years with 
the period from about 1890 to 1900, whioh in some quarters is 
■noisily proclaimed as the palmi^ days of the Society. (P. 15.) 

Mr. A. W. Wanvick has continued, in Ainerican Photography, 
to publish liig valuable experiments on the process of fixation, this 
time in reference to the fixing of prints. He finds, under his experi- 



mental conditions, that prints are fully fixed within a time which is 
a very small fraction of that which is commonly accepted as neces- 
sary in ordinary practice. (P. 16.) 

In a leading article we_ lay all the emphasis we can on the fact 
that the conditions under which Mr. Warwick's t*-sts are made, rjz., 
the fixing of one print at a time in a given quantity of hj-po solution, 
are altogether different from tho.«e wliicJi jjrevail in the handling i>f 
batches of prints which are ibeing fixed in the ordinary course. For 
this reason we cai.not accept his results as recommending much 
shorter times of fixation nor as confirming his sug'gestions that im- 
perfect fixing is less commonly the cause of stains in prints than 
insufficient washing. (P. 14.) 

We regret to record the death of Mr. George C. Whitfield, financial 
founder of the Paget Prize Plate Co (P. 21.) 

A con-espondent recalls his own method of producing effects sunilar 
to those of the Doretype (described last week. (P. 22.) 

In view of the present scarcity of hypo, economy of this chemical 
is desirable, and may be most efficiently practised by seeing to the 
temperature of fixing baths and by utilising those which have been 
employed for prints afterwards for plates. (P. 14.) 

The British Industries Fair in London and Glasgow has been 
postponed for two weeks. (P.' 22.) 



Juiuary 11, 1918.] 



THE BRITISH JOURNAL OF PHOTOGRAPH V. 



15 



lu ordinary working a mass of prints is dumped down in 
the rixing bath, and often enougli left to take its chance 
of complete fixation without the highly necessary operation 
of exposing prints singly to the action of the bath by 
continuously bringing the bottom one to the top. In 
th"se circiunstances there is no ground for supposing that 
ti;H speed of fixation of any particular print is anything 
l:k- the figures which Mr. Warwick obtains. The condi- 
ii< lis are against rapid fixation, for they include strong 
pressure of one print against another (thus hindering t.he 
access of the hypo solution), and also the partial exhaus- 
tion of the solvent powers of the bath. On the ground of 
his test<>, Mr. Warwick is inclined to make light of the 
suggestion which is often made that more prints are spoiled 
through insufficient fixation than from insufficient washing. 
But his tests, divorced aa they are from everyday working 
conditions, do not in any way support his contention. On 
the other hand, we can certainly say that practical experi- 
cii-e amply juatifiea the view that insufficient fixation is 
th*- cause of moat of the stains and markings whi<-li afflict 
development prints. By insufficient fixation we mean noi 
cliiedy fixation for an insufficient time, but omission to 
keep prints constantly fully exposed to the fixing bath. 
UV iiave had plenty of opportunities during the last three 
yi-.irs of proving to our own satisfaction the very complete 
tixation and the absence of after-troublea which result from 
the use of two fixing baths in succession. The other day, 
on visiting the printing room of a West End photographer 
whoae weak ranks among the be«t. we were pleased to find 
thnt the doctrine of two fixing liaths which we have 
preached in and out of season for a long time past had, in 
his case been further develojied into the practice of using 
no leas than three fixing hnths, through all of which each 
batch of prints was passed. 



THE ROYAL PHOTOGRAPHIC SOCIETY. 

The President's address to the members of the Royal 
Photographic Society, which we print npon another page. 
ir< .1 <-all fur the consideration of what more may be done by 
tile Society in justification of its il- ' ' 'iistitution of 
existing " for the advanifnient oi .ipliy." The 

a<l«lr<w8 thus is «*-• ■ document tor the members of 

th>- H PH. y»>t. tl . by virtue of its importance as 

'igraphy, necessarily invokes the 

I who wish to see its influence 

Vr"w. and who hold the conviction, as we do, that the 

i: I' ^ should take a leading part in photographic affairs. 

< ^ which of late years have been levelled at the 

K e mainly to the effect that it has localised its 

eff'jrts, and in the main we think they are true. It can 
|. ..A\.. i.f. denied that the Royal has existed too largelv 'or 
!>ers who enter the doors of its house, and too 
wis ignored the general questions which affect 
i>hers as a body and photography as a whole. If 
'•• out two instances which justify criticism of 
' • V are to be found, we think, in the attitude 

'' 'Val has displayed in the matters of 
.11 copyright law and in that of sur- 
N' '>rk. Proprjetarv rights in their photo- 

_ which is of importance to all ])hoto- 
' battles for an e<|uitable dealing with 
... , .. :ographs which t'M)k place whilst effort* 
n to introduce various Hills into Parliament and 
t .i.co them to legislation were fought by the Profes- 
sional Photographers' Association. P'ven when the new 
' ■ • •■ — ' -- ^ consolidated in the 1911 Copyright Act 
tl by tlve Royal in the way of familiaris- 
iTij; ITS nicmt>ers and photograpliers generally with the new 
legal prorisioaa in r<«pect of cojiyriirlit. In like manner 



suggestion and practical measures connected with the 
archwologically important work of survey and record 
photography have come almost exclusively from societies 
other than the Royal, although the Royal, by its official 
linkage through the Affiliation with a large number of the 
smaller societies, might reasonably have been expected to 
devote itself to propagandist and organisation work, such 
as would promote this application of photography in 
numerous local centres. Obviously undertakings such as 
these, in the case of a society with the professed aim of the 
advancement of photography, require to take precedence 
over the provision of dark-room or studio facilities for 
those of its members who can avail themselves of them. 

Nevertheless, in criticising the R.P.S. it is no more than 
fair to bear in mind that the last ten or fifteen years have 
from the nature of things been a more difficult period 
for it than that which covered the presidencies of Sir 
William Abney, Sir Henry Truemaii Wood, and the late 
Lord Crawford — a jieriod which now and again is held up 
to our notice as the exemplar of what should now be accom- 
plished. But during that period (from 1892 to 1900) there 
was more doing in photography. It was a period of acti- 
vity in several directions. For example, in photographic 
optics, in the introduction of new developers, and in the 
development of photo-mechanical methods of reproduction. 
In such circumstances it is a much easier matter for a 
society to lead an active life than it is when conditions 
generally are more stagnant and interest requires to be 
stimulated. The address, we think, scarcely made sufficient 
allowance for this difference of circumstances in its criti- 
cism of the Society's activity, or want of activity, during 
the |>ast few years. Moreover, much of its criticism is 
non-constructive in that it expresses regret that work being 
done by other bodies in the fields of professional phote- 
graphy, photo-micrography, radiography, and the holding 
of trade exhibitions is not being done by the Royal. It is 
constructive chiefly in the sense of suggesting friendly 
alliance with these bodies, although the character of such 
alliance is not defined and is not easily imaginable. Still. 
the address may do a good deal of good if, -at prompts in- 
dividual members of the Royal to press upon the Council 
suggestions of steps which might be taken in the interest of 
the whole photographic community. 

One or two matters occur to ourselves, and may, there- 
fore, be appropriately put on record at this perio<l of review 
of the past and resolution for the future. The Royal, we 
think, might greatly intensify the value of the technical 
papers which are read before it by taking steps to circulate 
proofs some days in advance of the reading of the paper. 
As things are now, it is the almost invariable rule, when 
discussion is invited, that ojiiuions are expressed by those 
present to the effect that the paper requires a study at some 
leisure before it can be adequately discussed. Thus it 
comes about that there is no discussion, whereas if the 
opjwrt unity were given for a previous perusal of a com- 
munication by those members interested in it discussion 
would be possible and profitable, and at the same time the 
u{»parMnity would be afforded of inviting to the meetings 
tlioSrVhJare not members of the society, but would in 
many cases welcome the opportunity of contributing their 
views. Moreover, the rule of having a paper set up in type 
before delivesy would be a preventive of a thoroughly un- 
worthy communication being offered to the Society. At 
present there is no such safeguard. We have been told in 
the past that the society has negatived this suggestion on 
the ground that, if proofs were circulated in advance, 
editors of journals would print it in full before it appeared 
in the Society's "Journal." We are confident that that 
fear is wholly imaginary. 

Another suggestion is that the Society might utilise more 



16 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[January 11, 1918. 



fully the facilities which it possesses for demonstrations of 
photographic processes. Along this line it can undertake 
services which cannot be discharged by any other means. 
There is no equivalent wliich a photograjjiiic journal, for 
example, can offer for actually seeing a thing done before 
one's eye«. In that connection the policy should be not to 
look askance at any demonstration which may hap]^n to 
be available from a commercial firm. Usually the manu- 



facturer has facilities for demonstration which are beyond 
those of the private individual. There is no reason why the 
society should not welcome such " trade demonstrations " 
witli the qualification that it should be the first photo- 
graphic body to jiresent the demonstration, and that it 
exercise a sufficient and proper control over the function, 
satisfying itself beforehand that the subject will be 
adequately dealt with. 



THE FIXATION OF PRINTS. 



[In the current issue of " .\nierioan Photography" Mi: A. W. Warwick describes the results of submitting the proctss of fixing 
paper prints to an examination similar to that accorded to plates and film, and described in the " H.J." of December 7, 1917. 
The scientific interest of his results cannot be questioned, but at the siime time it req\iire8 to be very clearly emphasised tliat the 
conditions of his experiments are very far removed from those of actual practice in fixing prints. His paper, as we point out in 
some notes on another page, requires to be read with a rucognition of this difference. — I'-ds. " IJ.J."] 



Ix the iixilion of a i)rint 'he plKitogiajdier has nu visual 
criterion to guide huii as Ic the ])rogress of the operation, as 
he has in the case of a negative. Absolute dependence must 
be placed on the adequacy of the time of immersion in a hypo 
bath of given strength and temperature. Printing pa|)er 
differs in no essential chemical respect from a j)hotogra))hic 
plate or film ; both should follow, therefore, the same general 
law of fixation. However, when the law which is obtained 
from the study of negatives is apjilied dii^ectly to the fixation 
of prints, it gives such extraordinarily short peritKls of time 
for complete fixation that the results are at first unbelievable. 
It is only by thoi-ough experimentation with different i 
strengths of solution and different j)ai)ers that conviction 
comes as to the shortness of time required to dissolve all 
unaltered silver bromide in a print. Even in a comparatively 
weak hypo solution it is a matter of seconds comjiletely to 
transform the silver into a solulile fi'rm, rather than of 
juinutes. 

From the data already ]iul)lished on the late of fixation of 
negatives, it is i>ossible to calculate the time required to fix a 
piece of printing paper provided that certain additional data 
on the latter are at hand. It is ]X)Ssible to test the accuracy 
of these calculations by simple experimental means, although, 
of course, it is advisable to check the results by rigorous 
methods. I,et us see, first, however, what conclusions we can 
come to from the data obtained from plates and films. 

It is tii-st necessary to know how much silver in the form of 
bromide we have to deal with in the case of paper. A certain 
l)oj)ular and excellent developing-out paper was c»irefully 
assaye<i for its silver contents and gave a result of 0.35 to 0.45 
milligrams of silver per square inch. That is, a 3i by 5^ inch 
sheet will contain from 6^ to 8 milligrams of silver, or from 
0.09 to 0.12 grains. This is about one-tenth or one-twelfth 
the silver content of an oixlinary- grade, of plate or film. 

The data obtained from the study of plates may be plotted 
in the foi-ni of a cur\'e on squared pajier. The oitlinates. or 
vertical Jine-*, give the amount of silver dissolve<l per square 
inch, while the horizontal lines, or abscissae, give the time 
elapsed. Curve A gives the rate of solution when a 20 per 
cent, hypo -solution is used. The results can be tabulated 
also by using the arithmetical formula governing the rate of 
solution already given, taking the amount dissolvefl in one 
minute, or any other unit of time, as a basis of calculation. 
The table so calculated may be compare<l with the results of 
the plotting by curves; lK)th are shown in ths next column. 
From either the curve or the table it is obvious that a film of 
silver bromide containing only 0.35 to 0.45 milligrams of 



silver i>ersquai-e inch should be dissolved by a 20 percent, hypo 
solution in from 15 to 20 seconds. This seems absurd in view 
of the instructions which accompany the paper to fix it in a 20 
])er cent, bath for from 15 to 20 minutes. 

A simple test, which while illuminating is not quite con- 
vincing, may be ajjplied as follows : Cut a piece of D-O.P. 
(gaslight pajier) into halves. Immerse <ine of these for 20 
seconds in a 20 ])er cent, hypo solution. Thoroughly wash in 
plain water, giving, say, six changes. Immerse l)oth pieces of 
paper in a 5 per rent, solution of sodium or any other alka- 
line ^uljihide. The untreated portion of the pajjcr will tui-n a 
deep sepia tint owing to the presence of silver bromide, while 
the piece of paper which has been fixed for 15 or 20 seconds 
only will remain perfectly white. An interesting modification 
of this test is to test the hypo-treated pa]>er as it comes out of 
the bath by touching the moist surface with a glass rod which 
ha.s been dipped into the suljihide solution. A deep brown 



SOLUTION or SILVER BROMIDE IN 
PLATES BY 20 l*Kn CENT HYPO. 

Time hiiWev Dissolved 

Seconds Milligrams iwr Square Inc}i 

5 0.13 

13 0.2 

0.38 

20 0.50 

30 0.73 

1.34 

2.C9 

Cotttjiair thig table tcitli Curve A at ihr lel't. 



spot will at once appear. Wash the paper in a tray with 
water and at each successive change touch a fresh place on the 
paper with the glass rod moistened with sulphide. It is 
interesting to note how much fainter the brown spot, thus 
formed, becomes with each successive wash, until at last after, 
say, six changes of water, no spot whatever is developed. 
Thus we ses that any silver contained by the pajjer, when 
lemoved from the hyix) bath, was in a soluble form, and we 
see the necessary r umber of water washes to remove it. 

It may be validly objected that this test is only conclusive 
as far «s the high-lights of a print are concerned ; it thixjws 
no light upon whether all the unaltered silver bromide has 
been removed fiian the image or not. 

.\. good vigorous print on the same make ol paj)er (D.O.P.) 
as used in the foregodng experiment was fixed in two succes- 
sive quantities of 10 per cent, hypo for 45 seconds at each 
immersion. The print was then washed in six changes of 
jdaiii water, followed by a ten-minute immersion in 10 per 
cent, hypo solution. Each quantity of solution, or water, was 




I^uary U, 19iai 



THE BRITISH JODRNAI. OF PHOTOGRAPHY. 



17 



•«»ted according to the colorimetric method; the results are 
iiated below. 

Kir»t hypo wash 93.0 per cent, extracted. 

>tei..n«i hypo w»«h 6.6 per cent, extracted. 

j-iret water wash .r:.... 0.5 per cent, extracted. 

Sei'-nd water wash trace extracted. 

Third hypo wash faint trace extracted. 

Thus we see that after 1^ minutes' fixatiMj all the iinaltere<i 
■Uvt-r bromide was extracted or eomvrted into the soluble 
•ilver salt. It is not unlikely that a portion of the silver 
shown to be extracted in the second hypo wash was carried 
OT«r from the first bath by the pai)er itself. Tests on plates 
with a JO per cent. hypo, solution irulicated a complete 
exiraitii.il of silver bromide from printing paper in 45 seconds. 
Tile effect of the image is, therefore, very slight. l>eing only 
to . auae a comparatively slight slowing up of the reaction. 
Tliere iM no afaaorption eithvr by image or paper. 

The more rigorous methotis of assay simply confirm these 
results. Testa were made on nnez{M-ise<l |>aper and prints. 
The amouttU of silver Hi Jiolved in each jieriod of time were 
determined by assay and the l>eads wei;;li<d, except in the last 
s^ai^. where they were too minuU- to weigh. In these latter 
cases they were meaiured by mirrom<>ter and the weight 
calculated on the l>a»is of a perfect sphere. The strength of 
hypo UM-d W.-IS 10 j>er cent, in each case. Tlie following tables 
five typical results: — 

Uatk or Soimo.v or Siivi.ii Hrumioi rRiiM I) o.p. 



Miuuie*. 
0-1 
1-2 
2-4 
4-6 
Paper assayed 



.Milligranu- <li»Mjlved 



|>er squall 
0.449 
0.466 
0.466 
nil 
nil 



inch. 



Rate op Solutio.v of Sn.vBB Bbomide trom a Pkint. 

Silver dissolved 
-Minutes. per square inch. 

0—1 0.325 

1-2 0.363 

2—4 0.364 

4—6 nil 

In both cases extraction was complete in practically two 
M.iiiut^. The extremely small quantity of one-thousandth 
of a milligram of silver dissolved out in the third unit of time 
cnild have no effe<t m the keeping quality of a print. 

It w.nild seem proved from these tests that plates and papers 
follow the same ijenenil law of fixation. Such small variations ■ 
as may occur are due merely to the slightly different physical 
characteristics of the emulsions and to the fact that in paper 
lioth sides of the film of emulsion are attacked by the hypo. 
Papers, indeed, should fix a little faster than plates, owing 
to the porous nature of the support allowing the hypo to enter 
iit the back of the film and the soluble silver salt to come out 
by exosmosis. 

It would seem clear, moreover, that the instructions to fix 
for twenty minutes err through an excessive fear of incom- 
plete fixation. The statement frequently made that more 
prints ore spoile«I through insu£Scient fixation than from in- 
sufficient washing requires qualification. The reverse of this 
statement is more probably true. 

The actual time of fixation absolutely to ensure the remo'/ul 
of bromides or chlorides of silver from a print depends upon 
the richness of the emulsion, the strength of hypo, and the 
temperature. With a fi-esh 10 per cent, hypo bath at 66° F., 
the ordinary run of D.O.I'., such as Velox, Cyko, etc., need 
not be fixed for more than five minutes, and ten minutes may 
U( taken as an extreme length of time. In the use of other 
special papers a few tests will indicate whether or not they 
fix faster or slower than ordinary papers . 

A. W. Warwick. 



THE ROYAL PHOTOGRAPHIC SOCIETY. 






lhr> I'resideiit, in No\etiibor lost mid now jii^t iiiii'ii-tlicd. Wo give it the title printed aliove, t-iiico 
>n "f the directions in which the S.xMety should work for its professed object of tht advancement of 



A »iL.«i'. 4^;> yr^t«id*y, vih»n i bad •' ;u.._ .,, addreaa you 

Irrxn tl<M |>'.Atf.>nii, that day doMd week of the 

wnr. I rmwrkmi that it aaa not, in u,-- i^^^er d roan tu say 
whatber or mi «• <houtd be still ensifed in iIm stragglf for life 
or death on the ooeasion of the n*xt addrcas tiofn this ehair. To- 
dfty w« And ooimItcs in the Mxteenth week ol the fourth year of 
ArmfMldoa, lh« temrinatioo ot which we oaaao* yet discern, bot 
Uis gr««C cnrMMa siwMn* which we are Kving now apfwar to be 
coanng more rapidly to a climax ; it i*. thersfore, important for 
•varrniM sod for every inatitaUon also to |i«jk ahead, and s«e that 
»i "portaiiitifa nf s new slate of tiling arise we lU-x in a 

p< •'ixe th««n. There is one view of the (utare upon which 

•\<' .i.nly whom I meet sMni* to be S|{Te<-<l. and that u, that it 
will im- my differsot in inMiy w*yf firmt the paot. How it will 
differ thtTK are many npioions, but that it there is only 

on«. In thinking over the topic ol my •! ' ^ I bare had 

to dccidp tiK-wMi the <4atms of the |«M omI the future, and to 
m»ke u|> my mind whether I sbotHd deal nith the work of the 
socisty, wihioh, sa you wiii, I an sore, admit, has been earned on 
■tdar Ctrl iiinslsiM us of th« ^im tut difficulty daring the iMt twelve 
months, or wh iih w I ahoold look ahead and ice in what direction 
we oDKht to lake Ihooaht to fit oofselTM for what Uee before us : 
ari'l .' •««ned to dm that the latter would be more in keeping with 
th»- ••■: d»nfy '.f tJip ilm>'. and if moi.' ■••v -le to the institution 
of 'f, • ii \.. ',)« president. 

In ...ii»i.i.- ^ 1. .. j'>ujtut;ra{dac Society 

shoald take, one aiiist oonaider the piir]>-->e for which it was 



fuiuidr<l. iixr Ai\t\ _\e^ii^ .>i^» u number of dist^iiiguiahed men, 
deci|>ly interested in the then youthful subject of photography, 
founded this society. In Iboso early days it was called "The 
PIvitographic Society of Ivondon," but I have not been able to 
find that it ever offioiaUy took thai title. The resolution passed 
at its first meeting was '^That a society be now established to be 
called ' The Photographic Society." " About twenty years after 
Uiis, at a time when there was much unrest in the 80cie4.y, it 
rluingeil its name to " The Photographic Society of Great Britain," 
and under thai title it was known until her late Majesty Queen 
Victoria gradously ordered it to be oalled " The Royal Photo- 
^ra|ihic Society of Ureat Britain." I know there are people who 
itsy. " What's in a name? " but in this cose I think there is a good 
deal. The society has a name which marks it out from all the 
otliw irtlBfR ataphic societies and camera clubs in the kingdom ; and 
I am sui* you will agree witli me when I say that that name 
iiniKWM u|K>ii us duties and responsibilitieit whidi Me also very 
<liflerent from Uu>«e which are home by the members of those 
•<her societies. It will be time usefully employed if we see of 
what those duties and responkbilities consist. 

It is a curious thing that tlie original founders of this society 
did not think it necessary to incorporate in its constitution any 
expression of the purpose it was intended to serve. There is no 
Matement of the "objects" of the society in the rules which were 
ftaMed at tlie inaugural meeting, but in the di8(.'.u8iUon which took 
place those objects were plainly indicated. .Sir Charles Ka«tJake, 
who was then president of the Royal Academy, and our fir»t presi- 



18 



THE BKIT18H JOURNAL OF PHOTOGRAPHY. 



[.January 11, 1918. 



dfnt took tilt chair, und in hi« openiug remarks spoke of the 
"idea of a society Iraving for its objects the cultivation and 
promotion of tiiis pnK-ess (iJiotography) and of its various applioa. 
tione"; and other speakers referred to the soraety as " insurmg 
tlie future progress of i>hatogr»phy," the " full development of the 
phot.,giup»HC art." arwl in similar i^raaeology. At the next meet- 
ing of the society, Uie fii-st regular one. if we exclude the inaugUTal 
meeting, its honorary secretary, .Mr. Roger Fenton, read a paper 
" Tjion the -Mode in which it is Advisable that the Society should 
Conduct its Lalxmrs": and in that paper he gave a .sununary of 
what, in his opinion, the society could and could not do. The 
principal objects of the society, he said, aje "the collection and 
the diffusion of inionnation, tiie verification and explanation of 
new discoveries, the comparison of processes and of their results, 
and the improveoieut of the nicchaniail and optical machinery of 
the art." The wording sounds (juaint and old-fas.hioned to-day, 
but there is no doubt what was in Mr. Feixton's mind; and the 
members of the yomig society did not question that their ohief 
executive othcer had taken a correct view of its functions. At a 
later stage in the society's histi>ry it was thought well to embody 
in its rules a definite statement of its purposes ; and the object of 
the society was defined as "the advancement- of photogra[*liy. " 
That statement remains in force to-day. It defiines or limits what 
we have thr power to do; but it also expresses what we ought to 
do. There may be other societies or caineau clubs to which maaiy 
of us belong which either explicitly state or tacitly assume that 
their objects aie the mutual assistance of their members — very 
e.Ncellent objects everyone will admit — ^but stUl fundamentally 
different from our own. 

I have made this brief digression inio the history of the society 
because I think it well that we should aU be reminded of the 
purpose for whicii it was instituted and which it lias officially 
recognised as its own. I suiJjjose there i« no one here who has 
ever atten>pted to bring in new memibei-s, which are so necessary 
if the society is to be kept active and flourishing, who has not 
been met by the question, "What will the society do for me?" 
and we must all have replied by pointing out the advantages of 
membership. But in doing so 1 wonder how often we have put in 
the foreground of tliose advantages " The privilege of subscribing 
one guinea a yeaj- for the nrh-cnrnnent uf p/intogrrrp/iy." And yet 
if the constitution of the society is to be accepted literally, that is 
essentially the " athantatje " of menibei-ship ; and if the member 
gets any i>ersoi>al facilities or pleasure from joining, they should 
be merely incidental, something in the nature of a by-product. 

Whether in the actual management of the society we have 
diverged at times from this high ideal 1 will not discuss. We 
who ha\e had to bear the burden of tJie society's conduct and 
management can at least never complain that the tonic of criticism 
has been withheld from us. 1 am not prepared to deny that there 
have been times when a little fuller recogiiition of the conditions 
under which we have laboured, and of the difficulties of the case, 
would have been more helpful. But ciiticism, so long as it is fair 
and unbiassed, is not only valuable, it is absolutely necessary. We 
have only to look at the political problems of tlie day to realise 
that, and to see that the co]ni>ul8ory suppression of criticism is 
very actively harmful. So I do not complain of honest criticism, 
while we may ignore any of the other kind. We will not consider 
how far there has been any basis in the pa.H for the charges 
brought against the society, but rather will look to the future and 
see how best we may carrj* out the work which it was founded to 
do. wihich I think we are all as fully agreed on to-day as our 
predecessors were in 1853. mid that it should be omr object to 
achieve. 

At the first glance the "advancement of photography" seems 
rather a vague phrase. What is the photography wihich we are to 
advance ''. Is it the scientific side of the processes which we use 
and the instruments which are at our command ? Is it the practice 
of photograjjhy a.s a j.rofession? its pursuit as an amateur's hobby. 
its use as a recording agent, or its application as a means of 
pictorial e.xpressioii ? Some of these aspects were hardly visible to 
the founders of the society; but I think, as far as they were, they 
would have recognised all of them as falling well within the spliere 
of our activities. F.very one of these branches it is our professed 



dutv as the Roval Photographic Society of tireat Britain to strive 
to advance. Some of them, the least favourable critic must admit, 
owe much to the society; others we have not done so much for; 
and if we feel this, it is well to seardi out the cause and, if w» 
can. to remedy it. 

I think one ever-present influence which has restrained the 
ai'tivities of the society in the past has been the fact that we have 
rather taken the \iew that we should not act until called upon to- 
do so. We may not always liave been as busy in finding out the 
requirements of the photography we are constituted to advance 
as we have been in doing the woik when it came to hand. In 
consequence we may have allowed opportunities to slip by. We 
mav resolve in tlie future to formulate a more enterprising policy,, 
and to seek tlie occasions in wJiioh we can. be of use, instead of 
waiting until they come to us. This is a direction in which the 
Uiembers at large' can do their part. One can understand that the 
acting officers of the society, Mti^dDyed as they are in carrying on 
it-s work from dav U> day, cannot waste much time in looking for 
fre!*i schemes which can only increase their labours and their 
responsibility. The regular meetings and the exihibition are im- 
IKirtant as methods of attaining om- objects, but they ought not 
to Iw the teginning and the end. Later on I hope to suggest other 
directions in which the society migiht look tor a useful outcome 

from its work. . , . 

Another matter on which I should like to lay stress is the light in 
v.liich proposed new ventures may be regarded. It is natural enough 
to ask. "In what wiay will this benefit the members?" I have 
neard such a question put many times and in such a way that it 
was plain that the questioner considered that if it could not be 
jiointed out that the indi\-idual members got some visible benefit 
the proposal was a bad one. What has gone before shows that 
this is not a correct view, if our constitution means what it says. 
There is no word in it, not even a hint, to suggest that the society 
exists to confer any benefits at all on its own members that it does 
not confer on everyone else who may be interested in the advance- 
ment of ph<>togiiapihy. 

For examjyle : we have a very large and varied photographic 
library, the best in London certainly ; ix)ssibly the bes.t in the 
world! If a non-member wished to consult it foa- a proper pur- 
pose I would throw it open to him as freely as I would to a 
member who had subscribed to the society for fifty years. The 
libiaiy should be looked upon as one of the means by which we 
advance photography. Organising it and making it as complete 
and its contents as widely accessible as is humanly possible appears 
to me to be one of the clearest paths towards out object. 

You know how my heart is in the society's exliibition. There 
again we have a direction in which we can do vahiable work. This 
yoar, for special reasons, the exhibition is free to all, members 
and non-members alike. It may not always be jjossible to adopt 
this policy ; but at least it seems to point in the direction in which 
we ought to go. I am not entirely prepared to measure the success 
of the exihibiiti'on by its balance-sheet, as if it were a commercial 
concern ; and if we had to choose between giving special privile^'es 
to membett's and getting together the finest collection of pictures 
possible, the privileges of members ought not to come first. Nor 
do I think for a moment that the society would suffer in any way 
by such an action. Financially it would not; as when it come.* to 
asking for monetary help, 1 have found tliat the better the case 
the more ready are our memliers to give their support. E-xhibi- 
tions play a most imix»rtant part in advancing pliot<^i-aphy, and 
no plans for tlie future development of the society will be 
coniiplete tliat do not consider means for nvakiihg ths pictorial 
exhibijtion much stronger. We must see to it that the facilities 
and inducememts we offer — not iiecessaanly in the way of awards, 
but in effective display, in the confidence of strictly impartial 
management, in selection by those who i>oesess most fully the 
confidence of the leading e.xthitoitors, and in similar directions- 
are such as wiill bring us the very cream of the work each year. 

Then there is the organisation of a proper trade exhibition, 
either annually or at such times as will be found moat suitable. 
We are only jiu«* teginnJng to learn, the importance of doing our 
utmost to foster and suijiport Britisih industries, and the photo- 
graphic trade is one in which Uiis country has played a very great 
part. It will be seen that I put the very widest ooristruotiou upon 



.Taiiuorx- U. 191&1 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



19 



til. iem» •' yiuMgmi^y" in our article* ol aaiocution : much 
«iJ«ir than tit-iv baa been an ii>clii>at;on to give it in the past. 
But it is nut limited thtre, tad I do not »e« why we should regard 
it a« limited. " ■ Pbot<JJRip''y " 'nc''<»'l^> photoRPaphic industry, aa 
nrll a« photogmpfcic aoience and p<hot' ignifMc ait. It should be 
rrcoyiMfd. therefore, aa well within the objecAa of tfce society to 
ie« tbftt the part this cuumtr}- hao played in photographic trade is 
maiatMaed and extended in the tutur<- This brings me to a sub- 
ject whieh mii^t to be con.iidercil much more oarefuUy than it 
ha-' be^n. We are th« "Royal Ph.ttognphic Society of Great 
Britain." We are natiooal by nani<- and constitution, and in 
ihe future UmC aspect must become moM marked with lu as 
with everybody eliw. It is not fitting, ft is not wise, 
that we should have in uur ranks ;tt any time members of 
enemy origin, and I am not sure that «• «nght even to limit this 
to thcae who are " legally " our enenties. Tbe oountiy has suffered 
law rnorh from sndt le^ fictions in the paai, and 1 hope is leam- 
int; ur has learnt its leasoo. The mere u a tw I ia i l iiMt of an enemy 
mug make him a British sidbjcot in the eyaa ot the law, but in the 
e>'(a of a man of ordinary pommon aenae it nay only make him a 
more dangeimia MMmgr, because a dist^sed one. The naturaliKa- 
tioo doctrine seems to me somewhat like fofiudding the sale of a 
poiaoa labelled " Poiaon," bat rncouniKing its sale in the guise of 
sweete. Tti« mnrtitolun of the society sbouM be such that nu 
cnamy of our mrn eoualry ahuulil Iw eKgibia as a member at any 
time, and mmt dacidediy should not b0 permitted to hold the 
bi|;hest hoti<r«irs which the society can tia t ow. This is a reform 
which aould lie better carried out now tbaa when the war is over. 
It would at least be a clearing of the decks for action. 

In carryint; •>at the work of the society in the future I would 
put in a plen. n<»t for extravagance at any time, but for a Ananoial 
poliojr which is jodiciooaly enteffirising. Tba si A a c r ipt ioM of our 
■wnbars ara paid to be expended on tha objeeta ot the society, 
snd neither to be spent in " faoiVilies " for members nor hoarded 
againat some mythical rainy day Beyond a rtaerve fund large 
•noq^ to prevent a bad year or two Iran interfering with the 
gvns««t conduct of the society, I doubt if we are justified in aaving 
■kioay at all. However, the preaent tima is not one when there 
is anjr need !>> justify saving, so I need not dwell on that side uf 
it. B«(nr«> leaving this subject I niay reply to a posasbte criticism 
that SDch a isiliry a« I hate sketched oat would affcet either the 
mrmhershif or the fooda of ths society a«hiarsely. 1 cannot believe 
it If we rely Dpon direct personal bensiU conferred, our mem- 
bership mutt be Iteitcd to the photograipliMa wlio are in a poaitcnn 
to take a<l\wMag* of thsm, not a very large tmniber even in 
London. On the other hand, it is hardly likely that there are not 
more than fifteen hundred |>en|>|e able aDd willing to snbaoribe a 
(MRea a year to a socieiy which they sea ia doing good work for 
phoiognphy as a whole. I am a firm balivrar that, provided we 
rh'xMp nor gioond rareftsUy. and occupy it well, Bts more ws do 
the nn.r^ we shall be enaMed l<> ia. 

' ' '-•for naeful work are cootinoally cropping up. A 

in-. ...^... .iuas case ia brfore the pubUe at tha p res tat momeot. 
It has bem ri^Uiy ptnpnsed that the natioo should form a coUec- 
li<^« of portraits of thoae who have played an important part in 
the (;rrat War. and tha portrait* are to ba photographic ones. In 

»«••' .1.-...^ nl photogrmph«» I iiacd not prnnt out the 

<n -lOg such a task with the banafit of skilled 

••' • ■' re. Yet the body which is forming the 

c" - "f* a|>p«w to haw rvcuanisad the ncoesaity at all. 

If in>- 1f•,^emment has to bay cloth, or hay, or ehefnicisls, it has 
now Imsrrf (he lesson that it nuait hara tha at s si ta a of cloth 
npnta, or africalt«iista. or ehrmisU: bot when a Department of 
tbe Oo twuBwt has to gat photographs it haa been content to p\it 
itself ill the hands of one commercial Unn, and in ila so-calUd 
" special i .illectsan " has limited admission to Ihe work of that 
firm. Thi« was a case in w4u<-h the society should have been con 
suited from the very beginning. At least it msgfat have prevented 
a groaa Uunder. Bat I think it coold hare done much more. It 
I* a aMi|Ds oppoMomty and one that gfaoold have lieeiv fully 
utilised. Tfir great photographic (lortniitiaU are individual manii- 
fattuTEtw. and the work in such a national ooUaction should lie 
the finer' ■>4, worthy alike of the subjects and nf the occa- 

sion. \\ lusy be said f < r the course which the National 



Portrait Gallery has ado|>ted, and at the be^t it cannot be much 
that is favourable, it is evident that uliis special collection oannot 
rise much above the level of the aveiwge home portrait album. 
The e.\eu!>e that the step has been taken to secure some kind of 
uniformity 'uniformity in ichat is not stated, iior is it easy to 
guess) is one wliidi is quite unwoi4hy of the National Portrait. 
Gallerj-. It is iv-t i>retended that the collection will be the work 
of some one leading photographer of high standing in his pro- 
fession, for which 9on>e kind of case nuigiht have been made out, 
and any other unifornnrity can only become a monotony. It may 
not even now be too late to prevent so great an opportunity from 
being lost, aiul if it appears to be in any way possible, 1 would 
suggest that we make everj- endeavour to save the natiotial collec- 
tion for the benefit of those who are to come after us, from being, 
what on the ])reseiyt lines it mnet become, a mere wasted eftoii. 

That such a scheme s4iould have been put into operation without 
any question on the part of the public shows how the public regards 
photographic ijortiwiture. It still looks upoli it as a purely 
mechanical product, to be bought at the nearest shop, like a packet 
of soap or a yard of calico. It sees no difference between a 
portrait by Furley Lewis or Histed, let us say, and one by the 
new Electric Photo .\rt Co. (let me add that the firm I have just 
named is a conception of my own, merely used as a type. I hope 
I have not be««i unintentionally quoting the title of any existing 
com|iany.) To remove that general but mistaken impression, it is 
y^ur duty as a society, so bur as lies in our powei-. It wxiuid 
"advance photoKrai>hy " to show the public, or at least the edu- 
cated puUit', that there are porti-ait )>hotogra)ihurs and portrait 
photographcTB ; that there ntay be qualities in a portradt much 
deeper and more vital than mere glo«s or ivtoucihed amoothiiess ; 
that the better wxM-k jvill live and seem modern and masterly, just 
as U. O. Hill's wiirk has lived; w<hile the other in years to come, 
if it exists at all. which is very problenntical, will merely cause 
a smile. It may take a long while to bring about such a change, 
but it is at least an ol>jeot well worth pursuing, and whddi in some 
ways could be undertaken from tbe very fVrrt. 

It seems to me that if such a national collection worthy of the 
name is to be formed, there are two qitite distinct sides to its 
fiimiation. One of these is the formation of the U.st of those who^e 
{■oiti-ails should be included. This is not llie work for which the 
Royal Photogra|ihic Society is better fitted than any other body. 
It caUs for a wider knowile<]ge of individimls and the part which 
they have played than we can lay claim to. W^et/lier the Trustees 
of the N'atioiail Portrait Gallery have that knowledge it is not for 
me to say. It is facr to assume that they have been selected 
liecause of their knowledge of painted [lortraite, such as hitherto 
the Oallety has dealt with, but it may be tlhat in. appointing them 
their knowledge of the subject* of paintings and drawings was 
taken into considevatioii . and if so they would be a very pi-ojier 
body to be entrusted with deciding whose portraits should be 
secured for the collection. But when such a list is prepared, tlien 
there is no other body that I know of so well qualified as the 
Royal Photographic Society to see tliat the notional ooUectioa 
shall include the beat photographic portraits tluit can be secured, of 
thoso whose lUMnes are on the Ust. Something more than " the 
usual thing " should be got whenever it is at all ixweihle. The 
work should be divided amongst those whom the photographic 
world recognises us the leaders in portraiture, or should have some 
distinctive merit. It is an oooaaion not only for forming a very 
valuable collection, but for making one whidi should show the 
high position whi<i» pliotograpWc portraiture has attained. The 
iieiBd- iar sui-h evwlei>ce is plain enough. The action of the Trustees 
fTf-»** 'National Portrait Gallery, who might be e.xpected from 
their position to kn<iw something of portrait photography, does 
not api>e9>r to have so much nf a suspicion of its position. 

It will be seen tliat whatever view I may take of the society 
and of its activities, it is not one wtvioh is Likely to find it short 
of orcupstion. Yet I have only named a few of the directions in 
which it can do \-alual)lo service. TJie last few years have seen 
tlie formation of pliotographic bodieB outside it, covering 
ground which it nvight be tihoDght the Royal Photographic 
Society should have covered. We have the Photomioro- 
graphic .«<x-ioty, the Professional Photographers' Associa- 
tion, the British Manufacturers' Association, the Uontgen Society, 
to name only a few. It is possible that with full activity on our 



THE BRITISH JOURNAL OF PHOTOGRAPHY 



[January 11, 1918. 



nart some at let '-f these 8ei)arato oigani«aUon« would not have 
Jxw needed. But .,...• Imve bee^i formed, a id we have to deal 
with fact*. At least we can »oe to it that witli all such bodies we 
iire VforfcinK iu hanuony. tiiat wilien they n«ed it they can count 
u|>oi» 8om«*hu»« more than the sympatlw of the Royal Photo- 
•graphic Societv, and that when, in the future, the idea of fresh 
!^cietie» to d^ with si>ecifil sides of photograpliy or offshoots 
from it are thought of, as is bound to happen, the first idea of 
their promoiters shall be to see how far it is possible to do what is 
wanted and still keep within the ciifJe of the society itself. 

It is UiTgely a matter of seeing that the niajiagement of the 
society is not' without imai!iiiation. and is able to exercise some 
Httlfl anticipation of what the future has in store. If we are able 
to do this wv may Iiope to see the Royal PhotograiJiic Society 
oxtend in influence" and in U8efulnp.>;3 far beyond its preswit limits. 
Personally, I am quite cxmfident that the possibilities of member- 
ship in the future are much greater than our present membership 
roll, after making alt allowances for the war, w^uld indicate; and 
while it is a mistake to suppose that the number of members is a 
reliable indiceition of the value of the society in its own .iphere, 
at least a large membership implies largo resources with wliich to 
carry on the work. 

In pointing out what may be done in future, I have not intended 
to make ;«iy reflections on the past. As you know. T have been 
<me of the council of tlic society for ninny years, and have had my 
share in its administration. We liave had limitations of many 
kinds, .njvd have done what we could with tliem. Some of these 
limitations have been imjiosed by circumstances, and some, I 
believe, have been due to misconceptions which time wdll remove, 
I do not expect the society will do everything which I think it 
.should do, and I hope it will do much that I have not mentioned 
ajid that has not occurred to me. But tlie iM;eseTit time seems so 
appropriate for a consideration of the lines which we ought to 
follow in the future, and so appropriate also for an attempt to 
widen those lines, and not to rely on precedent to such an e.vtent 
OR to liamper our usefuhiess, that I tliought it best to indicate 
some of the dire<-tion5 in which it might be done. The times are 
changing, an<l we must ciange with them. 

There is one more topic which I wish to put before you to-night. 
We hsive been looking into tlie future, let us come back for a 
moment to the present. Last year I was able to .-show you some 
of the aelijevemen/ts of the photographic branch of our Military 
Service, and to convey some idea of the wondei-ful part which 
photography in its hands is playing in the war. I w.".s unable 
then to deal with the naval side of the same subject, for reasons 
wJiioh I need not give at tlie moment; but now, thanks to the 
kind permission of Commodore Paine, Director of the Air .Services, 
I can jxirtially make good the omission. Time will not admit of 
anytiliing more than a brief resume of what Mir naval airmen are 
doing, and for obvious militaiy reasons miucli of their wonderful 
work must remain a sealed book, so far as the public aie con- 
cerned. 1 fear that even after the war Imlf oau never be told 
of their nuirvelloiis efforts. In a imilitary sense photography was 
almost an unknown quantity with us when hostilities commenced, 
and its v.'Jue for some time went unr«?ognised. But there has 
now been built up in the two Services a gigantic photographic 
organisation, which has a most potent influence on the war, and 
not, until it« history can be fully written will the tnie position and 
value of military photography lie understood and appreciated. 
\\hen that time comes I hope tliat we shall not find that our 
.•iociety has been in any way diffident in bestowing the highest 
honours U|K>n those who have accomplished so inucli in aerial 
photogr.aphy, 

The Ileailquartfrs of the Royal Na\al Air Ser\'ice are not very 
many miles from London, and at tliese the recruiting for the 
Service is carried on, and the men receive their technical training. 
The designing and perfecting of the apparatus required is also 
done in a branch of the s;imc establishment. Since 1914, not only 
has the apparatus beeji vastly developed, but the work done with 
it has been cori-espondingly extended. When the R.N.A.S. photo- 
grapWc service was formed, the gi-eatest height at whicli service- 
able photography . was crui.tidered posfrfblc was about 3,000 feet. 
Dui'ing 1915 this was increa.sed to 6,000 feet, which in 1916 was 
carried up to 15,000 feet, while lii-day most valuable results are 



oblsuned from 20,000 feet. Xor is there any reasoii to suppose 
tlwit tlie limit has been reached, or that when som*- mcana have 
bt#n devised to sustain life in still more highly ranified atmot^eres 
this record will not be bi*at«n. Fundamentally t<he cameras used 
by the naval and military .services are similar, bat th«fr» are differ- 
ences ill detail, Tlie military use an apparatus con.structed chiefly 
of wood, and operated generally from outside Uie machine, while 
the R.N.A.S. cameras are constructed almost entirely of metal, and 
are worked from inside tlie fuselage. The shutter is one of a 
strong, reliable, focal-plane type. The equivalent focal length of 
tlhe lenses varies from about 10 to 40 inches, and tftie plates from 
5 X 4 to whole-plate size. 

.\bout two dozen jilates is the number generally tised upon a 
photographic reconnaissance, bliough occasionally niore are re<}uired. 
These ai-e not jiromiscuously exposed, but cadi has its definite 
object. The jilates are developed, fixed, washed, rapidly dried, 
and a hundred prinUs b\ contact are made and delivered to head- 
quarters in .something les.s than three hours from the time when 
the machine comes to earth. Often, the machines reiuTiiing from 
these photogi-aphic cx])editians liave .suffered badl\- from Shrapnel 
and machine-gun fii-c. 

To take a few typical cases out of very majiy. I can tell you 
of one pilot who was flying at a height of many thousand feet well 
over the enemy's lines when a shot [lut his engine coir.,;iletely out 
of action; nevertheles.s, he planed htick and delivered his i xiwsed 
plates safely at the aerodrome. Another, 14.000 feet up, was 
attacked by a hostile machine, and his engine wan also totally 
di.sa.bled. In spite of this he drove his adversary down into the 
sea emd he himself planed back fourteen miles to the starting 
point with his photographs. Another pilot, shot right through, 
from front to back at tJie shoulder, wihile a long way from his 
base, was able to fetch his mark and make a good landing with 
his exposures. In the course of a reconnaissance to obtain a .series 
of photographs, another niaohine was hit in thirty-four places, and 
yet came back with the work. I could go on giving the.se examples 
almost ad injinitum. 

Probably you are wondering as to the photographic quality of 
the results obtained in such trying conditions. Believe me, that 
quite apart from the supreme importance that they possess from a 
military point of view, those I have seen have been technically 
first-rate, with such splendid definition ena.bling the ordnance maps 
to be corrected and ibiousht up to date in every detail, and ground 
of which no maiJS exist has been plotted out and efficiently laid 
down with a minuteness of record of the greatest importance to 
the Services. Tlhe operators who do this work are not merely 
photographers. Their duties necessitate that they shall also be 
keen obsei-vers, wireless operators, and expert machine-gunners. 
As far as observation goes, imagine what a fort or battery must 
look like from a height of 15,000 feet, the battery having been 
concealed by every device that skill can produce, with the direct 
intention of making it unobservable from tlie aeroplane. At that 
height it is little more than a spot upon the plate, but the photo- 
graphers succeed over and over again in getting that spot well 
centred on the plate, and do this wihile travelling perhaps at the 
rate of 120 miles an hour, and amid all the distracting attention 
of hostile aircraft. In spite of all, plane after i>Tane comes in with 
the desired detail correctly centred upon the plates. 

Photograpliy is also largely used to provide definite evidence 
that the motif has been accomplished both on sea and land. 

In concluding, I wish to take this opportunity to iiemind you 
that chivali-j- is not miissing amongst the British airmen^ On one 
occasion after a photographic reconnaissance in Flanders one of 
our airmen was flying at an altitude of 20,000 feet, and at that 
great height an anti-aircraft gunner was successful in scoring four 
direct hits in succession ; however, the pilot managed to bring his 
machine back to his aerodrome, and as he stepped from his machine 
he doffed has cap in recognition of the skill of the gunner. 

^ 

SECONn-LiEurEN.\NT Eknest Brooks, one of the ofHcial photo- 
graphers with the British Expeditionary Forces, h.is been awarded 
the Croix de Guerre Mr. Brooks has had a notable career as a 
photographer, and was I'ormerly a member of the Dnxly Gia})hic 
staff. ' He has .spent nearly two years on the Western front, and 
previously recorded the Dardanelles operations in a series of remark- 
able official photographs which were pnlilislied throughout the world. 



Jmumt)- 11, 1318. J 



THE BRITISH JOURNAL OF PHOTOCaAPHY 



21 



URATU UK MR. (lEORCE C. WHITFIEU). 

W'c regrst to Minounrc th« d«eUi, on December 31 last at 
Eistb<>urD«, of Mr. OwjTge C. Whitfield, at the advanced age of 86. 

Ill the d«ath of Mr. WbitAeM there paaae* away one who was 
. ! • ;lh tlie eariy days of Uir dry-pUte ii>du<try. When in 
'J tiie prize of £50, ufTered l>y Sir Joseph Paget for the 
i.f- j.r ' il'son, wa« awarded to th« late Mr. W. J. 

'ViIkoii. I tag aruiMid fur financial support, obtained it 

fr<im .Mr. W rmijeKi, ny whom the Pa^et Priz« Plate Coin|>any was 
eotJiohshed in the year 18dl. Mr. Whitfield, who was educatetl for 
the mcdicki profefaion, retained tlirou(cl>out the whole of his life a 
kccB intanat in photrQgrmpiijr, but for the paot fir.e:<i ye^r* he had 
tutccn no s(lfv« part in the buaineae of the Pa)(et CcmpiMiy. He 
ji.ifted the (oow) Rny»i Photographic Society in 1865 and at the 
tima (rf hix deadi was tbiM the member whose name has stood for 
tha kmgeat period upon the roU uf that body. 



meetings of Societies. 

e 
MEETINGS OF SOCIETIES FOB NEXT WEEK, 

MoHDiT, jAUt'AIIT M. 

DemtxinPtMUgraaklaflaalslj. V.P.U. Prtnl PotWello. 

<:Ut rl I.<ia4ea aaS CH»lsaili Phutocrspliie BoeMy. U>mb«r»' Priat Coai- 

prtltKnt. 

Bradford Ptiotomphie Boeiel}. " Photocrsplit sad Feeu> " BlMas. 
TusBPAT. Javi-akt is. 

Royal rhiUfumihli lodity. " dhalmpe*'* ' •■' ■*>• "(an." t'amberland 

CUrk. 
Bimlnckaai Pbotepaakie HoeMr. " Wsrvlrk." BaniM Baker.' 
Haal'> PlKMetrapkU: Soeistj. Y.M.CA. MIdlaai PMtofnphie Fcdetallon 

IViUolto. 
nhcffleid Phat(i(rapbl« Beoiely. "The Matle ol Iks Bible." T. W. IUn(orth, 

Mn.Baa. 
K*i(lil<-r as.1 Disule* Pbotocraplile AMcelailea. CrlltrlMii el Laaura BIMsa 

aiMl Ptiau. 
«lal<WMai PbotegiaiMa Mrf Maattta Boeistf. optolorUJ Work la Greai 

OUaa." A. H. Waka. ILA. 
Uaakla^ PlHMotrapMe aoaMy. -Oaa-Ugkt tttaUac oa Moclona," The 

WaaacaaAT, Jaaoaar U. 
lapmaioalMa aad Vtm laipreMlaaltiD 



Craydan Caaiera Clnh. 

t^rle. 
BdMol PlMtOfiaptiie Clab 

Pkotocmphy. J. C.>oi 
Iirord Pliolacrsplile Bodeir. 



■ilk (Masipiaite B< 
B. B. Wtlllaroa, r.H.P.>«. 



t. Vary 

atolie* In Salaral HMory," illuiraixl by Coloar 

" A c-bat OB Pietorial Pbel<>(rapby." H. Brtdfra. 
TacaftbAV, Jaxcast IT. 
• aad Ibsir Ulsraf 
ktaeeiatlcMi. Aaai 
Pkoiocraptale focistr. ** Oae Maa Bbew.' 



Hall PkoMnapkle Hoeletr. " Traaa aad Ibsir UisratT AMoelaUow." W. BoMon. 
IJ««(fsal AaMlcar PkoMCtapkle Aaaeeistloa. 



noYAL PHOTtM-.RAPHIC .SOt.ICTY. 

-Murrt.vo held January 8, the Pmideiit Ur. Jvha H. Uear in the 
'hair. 

Mr. H. Kssmh'nh Cvrke delivered a lecture on bromide printuiK 
in the course at which he dwek ufxai a nitntber of prints ilrawn 
from his experic.'M-e m this method. Bromide "was, he said, at 
4>nc« Ina ■■ iiis< and in<«t diflicuk printing prw-esa. He tuik that 
t-irw (o tba reason that effects wliich one worker miihl get <mi a 
Kivrii pa^ar saaiwd to be altonether lievond the power of aootJiei 
•■xperienead uavr of the aamc mat<-rial. He dealt with difficultiea in 
i» pia Ujning and with the diff<reiirn> exhibited by various papent in 
thii rr«|irct. 

Ill the diacuasKm Uwt fnUowed Mr. Melnloah referre<l to the 
<-aiiy removal of tarnish froni old uranium-toned prints by mesiia of 
j% hard rubber and atiggiated that the Mine means mi|{ht renie<ly the 
iimrkin^ (oaiid on Iba cdgaa ol black brnnidcs, as mentioned by 
Mikithrr membe.'. 

.\ hearty vole of thanks was stTtirded to Mr. Corke for hi« pa|>er. 

fROVDOX CAMEKA CLUB. 
Mamil* about (3wi»tmas lime tike the form of "conversational 
«^ailiiica," the Wedncaday before ('li>ii>tnias being attended by 
fonr coavmatiooklisU : that after, by two. The first evening was 
ioggf, and tha Rev. Le Wame cwtikl>liahed a record in railway 
traralling on hia way home, taking m icily twu hours five minutes 
from East Croydon Htation to Ni>rw<«id Junction, a djutance 
onder tw» miles. It is distrcsaing t<> think ttiat his profession 



forbade warm'ng laiiyuaf;^ on a bitterly cold nijjht. The 
L. B. and S. C. Railway, like eu overcooked emalsion, is par- 
ticularly susceptible to fog, and &. story is told of a pae.-senger on 
a platform who onee blew a cloud of toba<co smok*» acvoss the 
tiiick, :uid disoiganiserl the traffic for hours. 

I..a»<t wwk Mr. E. .\. Salt was dowi. for :i paj>er entitled 
■■ Bi'omuil V. Nature." hut at the la,«t moment atnuidoned it. to 
t'le pained sniprife of ihe hromoil enthusiast. Mr. (t. B. Clifton. 
who had journeyed down from Ealing to helj) in layiiig out the 
corpse. Still, the pa|>er is only iK)sti)Oiie<l. i;Mid Mr. Clifton 
earnestly requested an invitation lo the funeial directly the date 
is fi.xed. He did uot exjiress lit in this way, but all understood what 
was meant. Precisely, but the |)ei-tiiieni qiie.stion arii>e.« — whose 
funeral? In explanation, Mr. Salt said it seemed hiindly decent to 
start Immbing the pictorialists so close to tlie festive season, and 
he therefore |»ro|K>»ed to substitute " tosway " iboidei printing. 
He »howe<l how quickly and easily the holders could !>« printe;! 
round |ioKrait», and also tlie method of obtaining rogisWation on 
the film to (irevent the junction showing, simple in actuirt practice, 
but far from easy to de-crfbe without diagrams. A comb; nation 
print on " Noctona" gaslight paper was ina<le, anl the demon- 
strator f^ixike highly of the |>aper. which he regarded as an excellent 
l.iand of its cIl^.*. Much to his gratific.itioii he had hit ll-e correct 
i;\|iosiires on his first attemjits, and had 1)i««<tfully .-o written 
to Mr. (ireeii. of Messrs. tiriffin, wlio replicl tJiat he h-,wl been 
deceived by the eiioi-mous latitude of the pa)ier, wbii-h he (the 
s|ieuker| cynsidered to be an unkind and maalled-for observation. 
Prints from Cosway Umler films snpnilied by the Aut.ilype Co. 
reee^ve(l«««(>iiroliation. but other designs shown. Iiy generii consent, 
were deemed t<i be of such a clwracter as tu outmge the .irt'stic 
iilstincts of a coikroach. Perhaips this was [lUtting things a little 
siroii'jiy, but certainly the expression of the president. Mr. John 
Keane, as he gaxed on' the prints, seemed to indicate a possibility 
Ol «viithit;cally n;aiiufMctiiiiiig the now scMice acetic acid by a 
purely mental prtness. 

Tile rert of ihe eveiijig was filled by Mr. F. C. Wiatten. a 
veteran in photogra|rfiy, but youthful in his energy and activity. 
Uiifortmislely, bis son, .Mr. S. H. Wratteii. his removed to the 
other side of London, and the club scWom .«ees him. Had he he^ii 
pri-seiit ht woul.l luive enjoyed, as all did, a capita.1 tabloid laiiteni- 
le<-lure on the game of " Ixnvls," depicting its subtleties', ajid the 
atlitudes of the players recorded by fooal-plane exposures. The 
exposure.' were ii'idoubtedly .»hort, but in nn^ owes .aii]>eared to 
lie fully timed, never seriously under-exposed. X sei-ies of P.O. P. 
prints ' paiued loniid also <lemon»tfated the r^gatives to he of 
first rule quality. 

RONTCEX SOCIETY. 
At the meeting held on January 1, 1918, -Mr. <'8.il Darnell read 
t«o |Mi|iers comnionicated by Dr. Coolidge. of the General Elec- 
tric Uo.'s Research LnlHirMtorips, U.S.A. 

The first dealt with a new form of Coolidge tube, in whiiili the 
anticathude consists of a block of co|n>er faced with a small button 
1-1 tui-gsten. This is fixed lo a thick stem of o«>|»[<e«- which passes 
out through the glass neck of the tube, and terminates in a fine 
rad'utti.r. Tile anticathode is thus kept c<»il. .and does not in 
ronse<pience emit electrons as in the case of tlie earlier Coolidge 
tulie in which Ihe whole of the anticathode .'lieefiily becomes red 
Imt. The new tulie, therefore, so completely i-e<.tifies current that 
when an aiteriiating |ioteiitial is applied only one -iiliase of the 
current will p.iss 

f.m^ h« second |iaper, by Dr. Coolidge and -Mr. M-iore, the 
pr.rtiriilf or field .\-ray outfit of the United iStates Army was 
desrrfbed. A petrol electric unit supplies alternatiui; lurrent at 
110 volU lo a transformer anun/ed to give both high tension and 
heating curreTrts for the new radiator type of Cixjlidge lube. For 
sintplicity of control Ihe tube is worked at a constant potential 
of 5 in." equivalent spark gap, and the current is a<'- ■-'■"' t:> 
five niillianTi>tres for continuous running of the tiabe or ten ntil- 
liamperes for short jieriods. An electrically aclnated cuiitiul on the 
thnitlle of the engine nvaintains constant oiilimt. Tli« sniiall size 
oi the tulie, 3J in. in diameter, enables a close-fitting lead-glass 
shield to lie employi-d ; this is made in two parts, «uid .onipletely 
surrounds the tube, a suit-rble aperture permitting eji.-^ of tlie 



22 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



IJanuary 11, 1918. 



Commercially Cegal Mitelllflcnce. 

— ♦ — 

KoT.\iiv l'nor.>.;ii.M'Hic Co. (1917|.— December 18. £25,000 (£1). 
To eiiter into an a!;i'e<''"t'"t "'tl' Wiggins, Tape, and Co., Ltd., to 
aci|iiire anv a«8«t« of the Rotary Photographic Co., Ltd. Private. 
Cobham ilill Road, W. Drayton. .Middlesex. (149,168.) 
XKW COMPANIES. 
AssociATKi) Iixi'srHATioN AoENCiES. — December 28. Limited l)y 
gnaranti'i", 100 members. Liability, £100. To organi.se the pro- 
duction, printing, and di.stribiition of pijotogi'ttphs and pictuivs. 
to contract \Mitlj tJie British and other Govermiients, and with 
ne»spai)er3 and other publishers, etc. The first members of the 
Council are :— C. F. Bowden, 45. EsBe.\ Street, W.C. ; W. J. 
Edwards. 10, Red Lion Court, E.C. : B. Alfieri, 1214, Red Lion 
fourt, E.C. : J. W. Hay, 10, Farringdon Avenue, B.C. ; E. H. 
Wroughton, 46. Fleet Street, EC. ; T. King Warhurgt, 161a, 
Strand, \V.("'. ; G. Knight. 5, New Bridge Street, E.C. (manager 
Illustration Department, Central News). 



ReiDs ana noH$. 

— • — 

AiiKOTT Booty .\xd Co. — We learn that the busiue.is of Messr . 
AblHH.t Boioty ajid Comjxniy, of which the late Mr. Booty was 
for niajiy years itlio liead, ba.s been purc5iased by ^Jr. G. W. 
Hilder, who will contiiuie to carry it on, and will, we have no 
doubt, render tJie sftme efTicient service to jihotograiidiers an.\ions 
to buy or sell busine.?ses as did hi.s late predecessor. His address 
is 11. Clarence Road, E. Croydon. 

IxcRtASED Printing {'hahges. — A report received by the London 
Master Printers from the London Costing Committee states that 
the total increase in charges for printing since the outbreak of war 
amounts to 60 per cent., in addition to the increased cost of mate- 
rials — paper, 200-400 per cent. ; ink, 50-200 per cent. ; strawboards, 
300-400 jier cent. ; millboards, J50 per cent. ; glue, 200 per cent. : 
cloth, 100 per cent. ; and leather, 75-125 per cent. 

BfiiTisH Industries Fairs, 1918. — As it is possible that the new 
accommodation for tlie British Industries Fair (Glasgow), 1918, may 
not be entirely completed by February 25, and as it is of great im- 
portance that the British Industries Fairs in London and Glasgow- 
should be held simultane<iiisly, the Board of Trade have decided to 
po.stjiorie tlio opening of both fairs for two weeks. Accordingly, the 
period for which tJie British Industries Fairs in London and Glasgow 
will be open will be iMarch 11 to iMarch 22. 

Tmbun.^l APPE.4LS. — At the Headington Rural Tribunal, Walter 
C. Watts (forty), married, Bl, 59, Lime Walk, Headington, photo- 
graphtr, asked for further exemption on domestic grounds. 

Lieut. Uvven said that the military could not give such considera- 
tion to doiiiestic cases as they had been in the habit of doing. When 
they remembered what had happened in France and Belgium they in 
ibis country were well off, but it might not always ibe so if men 
could not be obtained. Further exemption for one month, final. 

Retouching Pencils. — A paragraph in "Assistants' Notes" for 
December 21 last, a-s to liencils wluch niav serve in retooiclhiug has 
brough lis a reminder from the American Lead Pencil Campamy, 173, 
Lower Clapton Road, Lr>iidon, N.E., that tlliey are able to supply 
a holder of the kind used by retouchers and stock all grades of 
lead to go into it. lietuuclier.s who may be exj)erieacing difficulty 
in obtaining the range of leads for their purjiose may be glad to 
make api-Mcation to tlie atkhe.'is given above for price lists and 
furtbe.' p;;rticularf. 

The Late Me. F. A. Bridge. — Since making a reference last week 
ty the oo.'inection of the late secretary of the Photographic Conven- 
tion wiUi music, we notice in the Horhiei/ and Kiiu/ilanil Gazette 
that Mr. Bridge was for many years superintendent of Henry Leslie's 
choir, ,ind afterwards acted as chuii-master of St. Martin's Church, 
Ludgate Hill. His first wife. Elizabeth Stirling, was organifit of 
Poplar Church and at St. Andrew Undersliaft. At the time of 
his death, which we now learn was immediately lirought about by 
a fall, Mt. Bridge was seventy-si.\ years of age. 



MorNTs AND Albums. — ^Messrs. Houghtons, Ltd., send us a copy 
of their full catalogue, just issued, of photographic mounts. Its 104 
j^ages specify and illustrate the firm's wide variety of both profes- 
sional and amateur mounts as well as albums and other items of 
photographic stationery, such as envelopes, negative wrappers, 
blctting-paper, etc. Inasmuch as prices of these goods have under- 
gone very considerable revision in an upwjvrd direction, the catalogue 
will undoubtedly be in demand on account of its obviating the 
necessity of correspondence! when further goods are ordered. Messrs. 
Houghtons will send a copy to any photographic dealer or photo- 
grapher. 

The Bo.vru of Ti:ai)E .Iournal. — Withitlie issue of January 3 the 
" Board oi Trade .lournal," in accordance with tihe more active 
IK)licy of the newly foi-med Depiirtmettt of Overseas Trade, appears 
ill a revised form and under the e<Htoi'^ip of Mr. Harcourl 
Kitchin, who, at very short notice, has left the " Glasgow Citizen " 
and is devoting his wide knowleilge of economic matters to the 
new official organ. Tlie fii'st issue under his control contains a 
prcfatoi-y article by the President of the Board of Trade, Sir 
Albert Stanley, pointing out the more active woi-k which it is 
hoped will be accomplisluxl through the "Journal." The issue 
does itself confirm this lio])e by its inclusion of articles of interest 
to the c«mnierciai world, in particiilar orae on the proviiisions and 
puiposB of the new Patents and Designs Bill, llie larger page of 
the "Journal" and its donbJe-cohiinn arrangeonenit make for 
easier reading of its con touts in the way of brief reports on foreign 
trade, ojieuings for British trade, tariff tJh.-uiges and similar items 
which were familiar in the "Board of Trade Jcimna,l" in its 
previous form. We do not wish to be hypercritical, nevertlheless 
we express the hope that in such reports the tedinical terms may 
be those commonly employed in this country. In a paragrapl» 
dealing with .Swedish export prohibitions we note that " phototype" 
(laper is exc^epted from other jiaper, the exportation of which is 
forbidvieii. It would be interesting to know exactly what ie 
meant hj " pliototype " |«iper. 



Correspona^iKe* 

*,* Correspondents should never write on both sides of the paper. No 
notice is taken of communications unless the names and addresses 
of tlie writers are given. 

',' We do not undertake responsibility for the opinions expressed 6y 
our correspondents. 

THE PROFESSIONAL PHOTOGRAPHERS' ASSOCIATION 
AND THE NEW ERA, LTD. 
To the Editors. 
Gentlemen, — In your last issue, Mr. Mackie, the secretary of the 
P. P. A., writes to point out what we thought every one knew : — 
(j) That the P. P. A. is not a commercial association. 
(2} That the New Era is a keen commercial body. 
(3> That the one has no connection with the other. 

(4) In the summer of last year you kindly inserted a letter in 
which this statement wis duly recorded, and we are grateful to 
Mr. Mackie for again drawing attention to this fact. 

(5) The New Era i.s a commercial body, out to make good profits 
for its shareholders. — \Vc arc, Gentlemen, Yours faithfully. 

The New Era, Ltd. 
(Archer Clarke, Managing Director.) 
20, Larkbill Rise, London, S.W.4. 



BACKED TRANSPARENCIES. 
To the Editors. 
Gc -tlemen, — About ten years ago I made some specimens similar 
to what are lefcrred to in the article on "Doretypes," but I made 
them either by the carbon process or by collodion transfer, backing 
them up in some cases much as is suggested. But I found if a 
ibackmg other than gilt was desired, I got fclie best results by using 
an enamel (such as Aspinall's) of the desired tint. When backing 
with bronze powder I liked that possessing the colour of gold leaf, 
but I do not think the best re.<*tilts can be obtained by applying 



Jouuarv 11. 19ia | 



THE BRITISH JOURNAL OF PHOTOGn\PHY. 



23 



wilh • unish. M> nivthud waa ti) otat t)ie tr«nt4>Am>ry. fir8t of all 
with a thin gold-iiae. ibriuhing it in with a aoft brush. Alluwing this 
<u Ary till it w»» " tacky '" I then applied tiie bronze powder dry 
with a piece ot cottoii wool, rubbing gently with a circular motion. 
Thit int'thud emNirea • sinootbiMea aitd I>i.-<lre otherwi»e iiiiobtaiiuible. 
I thought tbeae were very dainty, but I did not find them "catch 
4j>." Porhapa they might "■ take ' now. Yours taithfully, 

J. Douglas RrrcHiE. 
25. High Stri-et. P»i»ley, 
JMtoiTy 7, 1918. 

B.\«KIXO-l"P TR.\NSP.\RENC1E.S. 

To the Editors. 

Gentlemen. — The details o( tlie " new styl* " of picture called the 

]>ore-ty|ie. ({iven on \>»g« 4 of last week's "'B-J.," are most interest- 

■ •■ The new style may or may iwjt catch on, but with such a good 

<-onuneri-iaJIy it probably may. You, however, do well Ut 

, ^i that the plan of backing up transparencies is not new. and 

Toor reference to the famou» " Proud Tudi " (" Proud." I think, 

not " „'rand." but I may be mistaken) affair of Septeml>er, 1^3. 

<«I1* to mind that sensation of the year. How critics and experts 

"*'-'-'f| in front of BerKheim's picture aod );ue«sed again and 

ilwayt wrongly — the ppicess employed, and we were all in 

.....I .1 , ■■- .ilucer of it gave in details and offered to 

.;. .\fter such a aoimtion. and such an easy 

iiirtio.li i>, III- i'\|>i,uM.'(l tn lu, we thought we were in for a good 

lime will a new style, but nutMMly wanted it. and backed traiis- 

' < fizsled out. 

ickiug'iip trick, however, ii of a much earlier date. I liave 

lie two exielleiit examples produoad by one TItomas ('. 

-, of Ureenwich. one «f which bean llie date <>f 1857. They 

4iri., ■.( .xiurse. tiallodiun |HMilives. They were fir»t niixlr in the 

usual wav. tlie «iicil<- of the background waa llim -. r.it»Ml away, 

. plain class; il. .r the figure was 

k and the picti up with coloured 

liith. 'i: ••r on wliuli waa ikrtclied a landscape 

•uitable I 'in water -cokwr*. Lawrence boomed 

I lim. H i!if name of " Reiievu*. " because of their 

II' ^ but his daughter, who ia»e me the s|ieci 

iiie.iK. t- : ' I it he did not make much money out of them, as 

they ne<.' -ait. I a lot of worl., and a emisiderable amount of 
Artiatic ^kill. — Your* faithfully, L. T. \V. 



.»IS8I.ST.\.\TS- r.MQN8. 



9. ••J.iix ' 
I the ni.itter. 
the Mme token. 
the I'ldy pla-.es 
of mine, whiHie 
^o men only, and 
•ancietioii for an 
He must agree 



daV 



■ FW I»fc,«IHW It) 

OrtAinW an 



. tuggesl, but. 
i«h. I'oal mi- 
• union. An »' 
. tti.iii mining, 
id from t 
tu meet cLi.-.i -^, ^ 
himaelf. 
. .til empl<>,ve» of [■'■■.-I' -■-■I inde|)endence can 
m««ns that Ubnio - can be lieneHted 

"•-•, it sulcata ii> ,. >,,< writer has never 
>al obacnrantism that barred tiie path of 
~ 'its, and is not by any means tlesd t-i- 
I wnaker can be independent in normal 
fn>m jo'i to job — and the ntra nr'n 
•kill with a powerful |>rrsonality can 
iig up for himaelf or quitting the pro- 
"oor. 
I .•'•istanta will sead wages »/< need* ii.) 
times "Lux" couM Inve found a crying 
neceaaity for rrfonn in many parta of llie IT.K. and among all classes 
•of tha hnsiniaa, and normal times are coming back. I will conclude 
iiy Mvinx ttiat I am not a promtiier of maatar r. roan, nor yet .i 
• ii<;;riiiit!ed "twenty five bobber," and I stand l-> gain probably 
ni>thiiig by the forming of n mi 'ti N... gentlemen, I am out '.ir 
the Iteneftt of decent (.^'■''"-''■•''I'*"T!«. .iniiNiyers and employed, and 
1 want to think th-T ■ ^*y* " P.P." will be universalTy iii- 

Irrpretcd oa jfs/tr-t- !.>giapher and not as pn»priefor of 



lent. 



triit 
In 



m/rmsl 



premises or j>enuriou.< pauper, two expressions I luive luNiid more 
than once, wliich hardly tend to raise the prestis;e of photograpiiy. 

THER'I.r. 



CO OPERATIVE PLATE MAKING : THE NEW ERA, LTD. 
To the Editors. 

Gentlemen. —We much regret that through an oversight your Ex 
Cathedra paragraph in tl.c issue of December 28 last did not come 
before lu: until too Ipte to reply to it in the " B.J." of January 4. 

But now taking up the four points — factory, machinery, chemical 
supervision, and raw materials — in regard to which you ask for full 
and precise information, we would say. in re.'pect to the first two, 
that the plan of the ])roposed works has juat come into our hands. 
The executor of the estate v.ill only sell the freehold premi.ses, and 
the option expiring in a few days, the opportunity of securing u 
completely fitied factory admits of no delay. It is desired to form 
a small syndicate to piirclia.-ie this property, and to lease the 
premises, with option of purchase, to the New Era ('om|Ktiiy. The 
rent t« be paid will be the same amount as that paid to the late 
owner. This will give a retuni of 15 i>er cent, on the investment. 
and thus the syndicate will be landlords of their own freehold 
premises, complete with machinery, coating machines, boiler, engine. 
ice plant, d.viiamo, lifts, n ishing tanks, emulsion press, ventilation 
tubes and funs. There is also n reasonable quantity of usable stores. 
such as glass, gelatine, plate-boxes. pai>er and packing cases, all 
included in the purch.'.."e [irice. The directors of the New Era are 
in a |)»si«t,jn to pay this money, but it would unduly 
strain their reaourres. Therefore, they suggest Uiat it is 
to the interest of every piofessional photographer to state 
what amount of capital he would be disposed to put into the syn- 
dicate. Each £1 will be payable in five monthly instalments of 4s.. 
commencing February 1. and the first of each month following, as 
the directors would pay the cash down, and so secure the 15 per 
cent, for the syndicate. 

As regards chemicil direction, the service* of a thoroughly skilled 
emulsioiiiKt have been retained, and other staff engaged. So far there 
has lieeii no difficulty in obtaining the necessary chemicals ; the 
Ministry of Munitions ha^ placed us on the list for paper and other 
materials, ui'd as regards glass, should there be a shortage, we 
presume we shoiilil be in the same ])ositioii as other plate-makei's. 
Last month we had nearly a thousand jiounds' worth offered us at 
•piite a retisoi.able price. 

The real shortage at the moment is money, at more than half of 
our suluwriliers have been called to the colours, and consequentl.v are 
unable to fulfil their |>e('iiniarv obligations as stated in our letter to 
our shareholders in a circular letter dated December 15, 1917. 

While we are writing, we may correct an impression which lia.^ 
arisen in some instances, so wc learn, in regard to divi.sion of profits 
between ordinar,' and preference shareholders. While preference 
shareholders are guaranteed a return of 6i per cent., they will 
also sliere the profits equally ivitli the ordinary shareholders on u 
biisu shortly to be determined, according to the e.xtent of their 
hjiding in the New Era. Lt'J.. and the amount of their pur- 
chaaea. — We are, Ocnllemen. yours taithfully. 

The Nkw Er.\, Ltd. 
• Archer Clarke, Managing Director.) 

20, {.arkhall Rise, London, S.W.4. 



W».lli.v<;to.\ CAi.Ejiii.iRS. — We aro glad to find that tl-.e rcslric- 
tions on the use of paper-making materials have not altogether 
deur i—d photographers of the very tasteful wall calendars which 
Muss lie. Wellington and Ward have in the past been in the habit of 
diftrfbtiting. Thia year, in deference to the wishes of the Coiitroll.?r 
of Paper, <t much smaller number of these calendars have been pre- 
pared, but any professional photographer or pliotographic dealer 
who has not received one will, if jKissible, be supplied on appliuitioii 
to Messrs. Wellington and War-I, at Elstree, Herts. The calend<irs 
Uike the form of a handsome art board, measuring 12 by 10 inches, 
and bearing, in addition to a monthly teiir-off calendar, a photo- 
graph serving to remind the recipient of the qualitiee of the firm's 
products. In the case of one ol the calendars kindly sent to ou'-- 
selves, the subject is one of the charming studies of children by Mr. 
.J B. B. Wellington, which we have had occasion to admire at recent 
exhibitions. 



24 



THE BRITISH JOURNAL OF PHOTOGR.\PHY. 



[Janoary 11, 1918. 



JlnsiDcrs 10 Corresponaetits* 

— ♦ — 

SPBOIAL NO'EIOa. 

In ton$t9u*nee of gentral rtdneed ntppiiu of yaptr, a* <*« ru%ik 
of prohihition of tht importation of much vmod pmlp and frau, 
a tmalltr ipaet will h* ava i lablt until furthtr notiet for ropliet 
to eorrupondtnt*. 

Uortovtr, wt mil antwer fcy port if Btawtptd and addruted onvt- 



lop* i* tneUatd for r»pl f i B-etnt liOtrnational Ooupon, from 

rtadtri abroad . 
fA* fuU qntttiom and annetri toill it printtd onlf in tht ta*t of 

Mtgwrwi of t-nral inttrttt. 
Quoriu to b* antwtrtd in tht Friday' t " Jowmal " mutt rtath ut 

not lattr than Tuttda f {potttd Uondaf), and thould bt 

addrttttd to tht Xditort. 



PuoTO-ENGRAviNr..--The liead of the R.F.C. Scliool of Photography 
is Capt. P. R Bm-cliall, Training DivLsion R.F.C. Photf)-Sectioii, 
South Pa.rnborongh. Hants, but you appear to assume what, we 
believe, is not tlie case- that appoinlmeuls to the school are made 
from those not ah-e«dy in the R.F.C. Photo-Seiition. There is n<i 
school of photo-engraving officially connected witli the Ai-my or 
Navy. 
N. D. E.— We JjcHevc the material of the Agfa flashlight is 
thorium nitrat* nii.xeil with an equal weight of magnesium : or 
cerium nitraie in the same jiroportion. This is the iteon iron, the 
jiat^-nt specification, but it is most likely that the powder does 
not, c<>nres|xmd exaoUy with it. In the " B.,T." of April 26, 
1912, there is »■ lengthy article on flashlight powder, which gives 
the materials and the pro))ortion8 used in a large number of 
German powdt^rs according to the specifications. 
W. E. B.— If you trade under any other name than your own you 
come within the scoi)e of the Business Names Act, and require to 
register. So long as you register, and observe tlie orders of the 
.Vet in the way of putting your real name on stationery, you are 
not infringing the Act. The mere fact that you give a certain 
title to a building or an address is not a question which comes 
within the scope of the Act, or, broadly speaking, of aTiy Act. 
It is a, (pteeiion of your trading under a given name which you 
have to HonSider. 
A. V. — We fear there is no remedy whicli is in the least degree cer- 
tain for the removal of the stain from the twice-intensified nega- 
tive. There would be no liarm in trying a further bleach, and 
printing as you suggest on a vigorous gaslight j)aper, but it would 
want to be a very vigorous paper in order to get ample contrast 
from a bleached negative, at any rate from a negative of some- 
thing like ordinary \igour. It is difficult to guess what the stain 
consists of, but we sho.ild judge that it is not a developer stain, 
and therefore anything in the way of the usual clearing formulae 
is likely to be of no practical use. 
3. L. C. — A three-wick lamp is a very poor lantern illuminant, and 
you cannot expect to get a really brilliantly lit 8-ft. disc with it. 
With a good spirit vapour lamp, like the " Luna " of Hughes 
and Co., you can depend on a really brilliant disc of 10 or 12 ft. 
But the lamp of this type burns methylated spirit. If you can 
get -ipirit it is quite easy to use and regulate the light. We can 
understand that a lantern for an oil lamp is fitted with a long 
chimney, and the latter is necessary in using the oil lamp. It 
wouldn't do to cut it down while you are using the lamp, but 
with any otlier form of light such as spirit vapour or acetylene tire 
tall chimney could be replaced by a simple lightexcluding cowl. 

V. R. WHEmi.iX)N. — No one lens is reaJlly suitable (or so many 
diii'on»iiti pur|H>t.e«. If yo>i mu»t have one only we should say 
you had mucJi Ixitter clxjose a good ^,6 ana.stigmat. While you 
sa^rifrue fioniething in speed you gain much in the way of the 
i4>finiti«ti required in the onldoor work. Neither of the two lenses 
ywl nanw is up to n.ucli. Vour beat cour.se woidd 'be to get a 



secondhii^iul ;uia>tigniat by a leading maker from one of tit» 
.secondhand firms. About itlie beet ft>cal lengtii would be 9 inches, 
although tliis would be awkwardly long in coofined situaitiooe. 
Here lagain you .'ire asking too much of one leais. For many of 
the purposes you name yoai -would want a lens of 5 incites focus 
on i> half-plate. 
('orvBH;HT IN" TirK United .States. — If an Englishniau automatically 
obtains rights in -\merica, does he need to i-egist«r his copyright 
at W'ashington? It is clear to me from the handlx)ok you have 
issued, and also from the copy of the American Act dealing with 
copyrights, that it is necessary for American su/bjects to register 
their pictures it they wish to obtain protection in U.S.A., and I 
cannot think that an Englishman, -without taking any trouble or 
going to any e.vpense, v;ill obtain rights in America. Further- 
more, unless the i)ictures aiie registered in Washington, it would 
be very difficult for the U.S. Government to give him any pro- 
tection, even if tliey had every wish to do so. — C. N. 

It is not possible to an«^ver your question specifically, because 
it assumes conditions which, according to our reading of United 
Ktates copyright law, do not e.xist. In thi.s country, under the 1911 
Act, copyright is (to use your words) automatically created by the 
making of the work — literary, artistic, etc. But in the United 
States it is necessary for the creation of copyright to observe the 
formalities in the way of registration at W^ashington and marking 
all copies in the case of artistic works. It is not automatic. This dif- 
ference re<iuires to be borne in mind in inteiT>reting the U.S. 1909 
Copyright Act in regard to -wliat this latter says as to copyright, 
which may extend to those who are not citizens of the United 
States in that country. Tliis Act says that such rights may extend 
to aliens who at the time of first publication may be domiciled in 
the U.S., and also to subjects or citizens of other countries having 
reciprocity arrangements, as regards copji-ight, with the U.S. We 
do not think there i.s any reason to suppose that the alien domiciled 
in the U.S. will be excused the fornrahties of registration at 
Washington, etc., and therefore the alien who obtains copyright 
on the basis of a rec iprocity arrangement between his country and 
the U.S. would, we think, e<iually be reciuired to comply with the 
U.S. rules as regards registration. 



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THE BKITISH 



JOURNAL OP PHOTOGEAPHT. 



No. 3011. Vol. LXV. 



FRIDAY, JANUARY 18, 1918. 



Peice Twopence. 



Contents. 



Kx C4smsoaA 

Castr ASB Putimrvi. Etxo- 
rucrn 

Tm RcTAiB or Anuum 

^ Uwrraiui SuM-Bca roa l>a«Al. 

TtAJiwT. BrU. CWmUa .... 
-^rtaiiAaB* *» CotrraoL » Cin- 

uttooatm Pxutcnoc. Bj J. 

T. CMhnU 



Dun or Ma. C. H. Hswrrr. 

AMinAan* Korsa 

P*TciiT Nawi 

FoatacoMias Exaiamoa* ... 
MaanaM or B aaa i iaa 



rAot 

. 31 

. U 



CoaaaacuL ua Lcoai. Irrai.- 
uaaaca J4 

MiwaAaaKMsa JS 

S 



Tht aummary of amUnU tehich tuually oeeupUt tMt Imetr hall 
of tKit t e l umn wUl bt found at tht foot of Oit page ovtrltaf and 
mlledMtimmloUpUuidtMtr* wkiltt iU regukur /ontUm it nqmr»d 
for wolMw rthtimf to Umft n iuom m t " B.J. dhmcmae." 

T>M Flrut of tha 16,000. 

It i» always aomeihing of a. aatisfactaoo U> us to g«t the 
first finished copy of the Almanac. We are getting on. 
At any rate, the binden have a atock ol all the " aheeta " 
which make up the book, and, given a ohanoe, will keep 
busy in placing them witiiin the familiar yellow or green 
covere. In ordinary timea we could depend on their 
getting out two or three thouaand a day ; now their daily 
output is. measured in hundreds, and may be reduced to 
nothing every now and then by peremptory orders to con- 
centrate all their »t*ff on work of military urgency. 
Neverthele», we have reasonable hopee th&t in the early 
days of next month there will be thousands enough of 
tlie 1918 Almanac to fulfil the orders throughout in the 
I'nited Kingdom. 

Our fourth war-time Ahiianac, for all its rationing is 
still a volume of 660 pages. We daresay that many people 
will prefer it U> the issues of over 1,000 pages, which in 
pre-war times were unique, we believe, among trade publi- 
cation* Actually iU text-portion omit* nothing for which 
lU readers will look. The oocwdon for certain sections, 
for example, review* of new apparatu., has gone, but to 
•II intent* and purposes the Almanac oontinue* to be the 
iip-to-date " enquire within upon evenrtliing " which ha^* 
been ito character for years pact. We must try to find 
•pace m our advertising pages for extract* from the " Con- 
tent* m order to show the number and diversity of the 
nuWect* deatt with in the forthooniing iswie. 

Smaller bulk has been conditioned chieav by the smaller 
atie of advertwwnenta— in part our publishers' own re- 
striction— but the number still provide* a survey of the 
British photographic trade, and our readers can render a 
real service to this country and to friends in neutral 
States by sanding a copy of the Almanac to tell it« Ule of 
British reaoniw.. Under the rcf^ulation of the PoBt«l 

"u??? P '."*? **P'*" <=*» •»• '*"* only through the 
publishers of the Almanac. 



EX-CATHEDKA. 
Sulphide A writer recently stated that " iu 

Toning. theory " a sulphide-toned print should 

have the same colour whether toned by a direct or an indi- 
rect process, but we fear that neither theory nor practice 
will quite support this statement. In a direct process, such 
as the hjrpo-alum or liver-of-enlphur, we operate directly 
upon a blaok silver image, therefore at any intermediate 
stage of the process the image is a combination of a brown 
with a black deposit. In the indirect process we work upon 
a white silver-bromide image, and in this case, at an inter- 
mediate stage, the image is a mixture of a brown and a 
white deposit, and is necessarily of a different tone from the 
intermediate image produced in a direct process. If both 
prooeeees are carried to the extreme so tliat brown silver 
sulphide alone exists moat probably both will be of the 
same colour, but while tlie indirect process is a rapid one, 
and therefore speedily reaches what appears to be finality, 
the direct process is always a slow one, and probably very 
rarely, if ever, is allowed to reach a similar stage. In any 
:;ase, operations of similar type seldom reach finality, a 
little of the original deposit always remaining. The 
bleached image cannot be completely re-de^eloped, and it 
is not likely that it can be completely sulphided. Neither 
does it seem likely that the black silver image can be com- 
pletely changed by a direct sulphiding bath. Theory, there- 
fore, suggests that in each case a little of the original 
deposit is likely to remain unchanged, and a very little 
black metal in the one case, or white bromide in the other, 
will be enough to cause considerable colour variation. 



The Miniature .\ suggestion in the " Scientific Ameri- 
Raflax. can " that a pocket reflex camera would 

be a great boon meit with the disapproval of our corre 
spondent Mr. Graham M. Nicol, but nevertheless we think 
the idea not at all unworthy of consideration. We have 
had considerable experience with one of the small 4J x 6 
cms. i>ocket cameras, and it is an undoubted fact that 
there are many occasions on which it would be highly 
'Tl"ip**fl"" "° to ^ able to make sharp focus perfectly 
rertaiBii ^ur American contemporary api)eared to havf in 
view a "folding type of instrument, but this complication 
seems hardly necessary in view of the fact that our camera 
can be carried quite easily in a side pocket even when fully 
extended. There should be no great difficulty in making a 
miniature reflex with a focussing flange front, and lens 
shutter of the liebd type, that should be no larger than 
the extended camera as it now is, and the complications of 
the ordinary reflex could be dispensed with. A folding 
type no bigger than " a pack of cards " would doubtless 
be an improvement, but until such a type is designed we 
think a miniature non-folding reflex would be a distinct 
advantage, and we think a very popular introduction. Of 



26 



THE BRITISH JOURNAL OF PHOTOGR.U'HY. 



LJaiiuaiy 18, 1918. 



the popularity of small plate cameras there is no doubt 
^s•hatever, and any real advance iu design is sure to be 

welcomed. 

* « » 

Missed One of the industries which have been 

Business^ fostered by war-time conditions is that 

of the cheap enlargement, which seems to be flourishing 
to such an extent that it can afford to take a decent-looking 
shop to display its outrages on [wrtraiture. This is detri- 
mental to the interests of the legitimate photographers who 
possess the original negatives and could produce a much 
more satisfactory result. We fear that this state of things 
is due to the fact that many photographers charge too high 
a price for enlargements, while others who.<e charges are 
reasonable do not make a good show of their work, and 
alec do not display prices, so that possible customers who 
would willingly pay a guinea gravitate to the che^Lp man 
who loudly trumpets "this size for 3s. 6d.," and having by 
this means secured a nibble, books an order at a vei-y much 
better price. Of course this is legitimate trading on his 
]>art, but it is uj) to the more reputable of the photo- 
srrapliic body to endeavour to keep a decent class of cus- 
tomer from drifting away from them. We believe that 
much could be done by showing special lines of " service " 
sitters, male and female, and also emphasising the fact that 
any photograph could be reproduced. As it is, many people 
are afraid to take a dilapidated postcard into a prosperous- 
looking studio, and so the work falls into the hands of the 
enlargement shopkeeper, who is often only an agent for a 

trade sweater. 

* * « 

Supplemen- There are many operators who are either 
tapy Lighting, vinaware of, or prejudiced against, the 
use of artificial light in conjunction with daylight. Yet 
the practice is a very old one, and has many advantages. 
It is particularly useful where a studio has a sidelight 
only, which answers well enough for heads and three- 
quarter lengths, but gives unequal illumination when full- 
lengths and groups have to be made. In such cases a 
supplementary toplight takes the place of a glazed roof, 
giving effects indistinguishable from daylight and con- 
siderably shortening the exposure. For tliis purpose the 
best arrangement is to use the light of an arc or half-watt 
lamp reflected from the ceiling, no direct rays being allowed 
to reach the sitter. The lighting is, of course, very soft, 
]>erhaj>s too much so to be used alone, but conjointly with 
a more direct light either of the same class or daylight it is 
quite satisfactory. The necessary fittings are simple. One, 
or better two, lamps are hung as near the ceiling as pos- 
sible, the lower part being screened off by a hemispherical 
reflector which directs the light upwards and gives the 



SUMMARY. 

A jjapev recently read ibefore the Society of Alotion Picturo 
Engineers in New Yorlt ia an e.xcellent contribution to the more 
scientific coi trol oi the intensity of illumination in the projection of 
cinematograph pictures. It has its application also to ordinary 
optical projection. In both these spheres methods of control by 
niea»urement hive hitherto been largely neglected. (P. 29.) 

Mr. G. C. Weston, in a contributed article, describes the construc- 
tion of a light but breakage-prcof box for the postal carriage of 
lantern sli les. (P. 28.) 

We regret to announce the deith on Tuesday last, at the age of 
forty-five, of Mr. C. H. Hewitt, for many year.s instructor in photo- 
graphy at the Photographic School of the Regent Street Poly- 
teclinic. (P. 31.) 

Some practical hints on repairs of photogi aphic apparatus, such 
as can be carried out by tlic photographer himself, will be found in 
an article on page 27. 

Business in enlargements oftea goes to the cheap tout, sometimes 
from photo^raphe.-s' excessive prices and in other circumstances 
from lack of bringing before possible patrons of a studio the service 
they can there obtain in the way of enlargements. (P. 26.) 



" white cloud " illumination which is so highly appreciated 
by the portraitist. As regards curtains, head screens and 
reflectors, the combined light may be treated as if daylight 
only were being used. One advantage of fixing two or 
more lamps is that the lighting may be modified by 
switching off one or other of them instead of cutting off the 
light by means of screens. 



Design 
Copying. 



A small branch of photography which 



might well be developed by photo- 
graphers in manufacturing districts is that of the dupli- 
cation of designs and drawings by photography. The 
work is very easy as it is mainly confined to line 
subjects, and the quality and colour of the image are 
of little importance provided that absolute accuracy of 
the lines and correctness of scale lare ensured. It is still 
the practice in many factories and even in some litho- 
graphic establishments to rely upon hand copying for this 
class of work, but if such manufacturer can be convinced 
that they can obtain greater accuracy in a shorter time 
at a fraction of the cost they are likely to patronise the 
photographer. Non-distorting lenses must, of course, be 
used, and it is desirable to work as much as possible with 
cameras set to reproduce to a given scale both for making 
the negative and the enlarged or reduced bromide print. 
As an example of the sort of thing that is wanted, we may 
instance a rather elaborate diagram consisting of a 
number of graphic curves with notes and figures on the 
squared paper. A subject of this kind, which took a 
skilled man three days to copy (the size was 40 by 22 
inches), was copied in both the same size and to half- 
ecale in three hours, and the photographer was well paid 
by receiving a third the cost of the hand-drawn copies. 
Most factories and drawing-offices now possess blue print or 
ferro-gallic apparatus for plan copying, but this neces- 
sitates a tracing being made. This is never so sharp as 
the original, and requires careful checking as to dimen- 
sions and details. The camera method takes the original 
as soon as it leaves the draughtsman's hands, and copies 
can be delivered before a tracing could be done. The 
work should be charged for on a commercial basis at, say, 
three times the cost of the materials and labour expended. 
An isolated job naturally would not be worth doing, but 
if only three or four plans per week came in an appreci- 
able addition to the profits of a business would result in a 
year. Quickness in delivery is a necessary feature in 
work of this kind. It is useless, in most cases, to put a 
job aside to be done when some spare time is available. 
Fortunately a camera and a few electric lam])s by which 
such copying can be done at a moment's notice call for 



A national sdieme oi i econsi-ruction is in contemplation whereby 
electric current shculd be greatly cheapened rnd nuich more widely 
distributed. Even if the large claims made for the scheme nre 
proved not to be iealisi;ble, there is little doubt that in the future 
the legishitive obstacles to the distriibution of electric energy will 
be in large measure overcome. (P. 27.) 

A glan^-j at the essential differences between direct suljihide 
toning, as in the hypo-alum process, and that of bleaching •>nJ 
sulphiding is taken in a paragraph on page 25. 

A daylight etudio which is defective from lack of top-light may 
be made satisfactorv in this respect by the suita^ble installation of au 
artificial top-light.' (P. 26.) 

Ihe coi)yin2 oi nianr.f.".cturers' working drawings, etc., may form 
a small side-line of the photographer's bufine?8 if it can be done 
jromptly and at commercial I'ates. (P. 26.) 

At the Bath County Court ilast week an action was heard in 
reference to a dispute, in which two lady photosiraiihers were the 
plaintiffs;, as to '.vhat constituted a basement. {P. 34.1 

A recent patent specification describes an installation for the 
machine development. fi.Mng, washing, and drying of cinematograph 
films. (P. 32.) 



1 



Jiuiiu>r> 18. 1918. J 



THE BRITISH JODRNAL OF PHOTOGRAPHY. 



27 



little outlay and a corner can usually be found for the 
installation where it will be always ready to hand. 

CHEAP AND PLENTIFUL ELECTRICITY. 
Anoxi; the matters which have had the attention of the 
Ministry of Reconstruction is the conservation of our 
national supplies of coal, a queetion which has been dele- 
gated to a Conurittee (the Coal Conservation Sub-Com- 
mittee), which has now presented an interim report. 
Certain of the features of this report are of such a sensa- 
tional character— or, perhaps, it would be more correct to 
say have been rendered sensational by the daily Press — that 
some roninient upon them appears necessary. Such com- 
ment is not out of place in a pliotograpliic journal, inasmuch 
as the report of the Coal Conservation 6ub-Coniniittee is 
largely a recommendation of a national scheme by which 
electricity shall be rendered both plentiful and cheap ; and 
it is hardly neoessarA' to point out that photographers, as 
consumers of electric current for both light and power, are 
interested in denrelopments such as these. According to 
Hie interiiji report, it is stated that in the United Kingdom 
eighty million tons of coal are consumed for the production 
of power at a cost of £40,000.000 at the pit-head. It is 
declared that by an up-to-date and national scheme of 
electrification fifty-five million tons of this coal could be 
saved, equivalent to £27,000,000. Other means of conser- 
vation in the way of recovering by-product* would effect 
altogether an economy of £100,000,000 a year. The 
pno^oaed sdieme is, therefore, to put down a small 
number of immense power stations on sites favour- 
able for the delivery of coal and water, and from 
these to distribute electric supply by trunk line* 
throughout the country. Aj>art from its financial 
economy, such a scheme would clearly confer enor- 
nious benefits upon the oommunity. It would, if 
realised, abolish the smoke and atmospheric iKillution of 
large manufacturing centres and would contribute to the 
prosperity of many minor industries by the greater cheap- 
ness and wider distribution of electric power. At the same 
time, the obstacles in the way of the scheme are numerous 
enouijh to subdue the hopes of anv overnight revolution 
which will usher in an industrial nnllennium. In the first 
place, sites for such power stations have to be found where 
both wBf»»r and coal— tlie one is as cHential as the other— 
">■'■ -easible. In the second place, existing electric 

IK)w ns would have to be scrapped : and. thirdly, it 

would be necenary to ascertain fully the economic benefit 
which such a scheme would confer upon the country as a 
whole in relation to the service in the way of the supply of 
light and power which is at present being rendered by the 
f»» oompaniee and is now oMaining a higher mcaMire of 
importance in reference to the recovery of all kinds oi 
residual products and their utilisation in the chemioul 
industry. 

Whether the scheme at a wliole comet into being or not 
it may, at any rate, be taken as certain that the next few 
years will witneaa a greater distribution of electric currti.t 
and a removal of the legislative influences which for ♦..hirtv 
yean have hampered the electrical industry and have been 
the cause of the chaotic and often unecono'iticnl c<ii'i(Ji(ion 
into which the undertakings for generation of electric 
current have come. Photographers have good reason for 
watching such developments and giving them any such 
support as. locally, they are able to do. The measure of 
our backwardness in this country in the distribution of 
electric current is to be found, apart from many other 
signs, in th*- ' ■ v of places even of considerable size 

where no el. .ply is available. It may be believed 

'" 't ■'■i:"' .cr view of the imi)ortance of cheap and 

I ■'. . . current, there will scarcely be a photo- 



grapher in the country who may not, if he so wishes, instal 
electric light in his studio. And when that is the case there 
will be many further applications of electric motive power 
in the business of photography. It is not too mucli to 
anticipate that a clean and convenient form of power, such 
as is available in an electric motor, will prove capable of 
displacing a great deal of the hand labour which is now 
employed in printing, washing, and drjdng photographic 
plates and prints. In the matter of electric heating we 
still have a long way to go; electricity will have to be a 
very cheap thing indeed in order to become as economical 
as gas or certain solid fuels for the warming of premises. 



THE REPAIR OF APPARATUS. 

Various little repairs, such as that recently described by 
a contributor who rejwired a leaky dark slide by seccotiniug 
washleather round the rebate, are usually necessary at 
periodic intervals. Slides will develop ligbti-leaks as will 
also cameras, while dead black wears off and screens become 
loose in course of time. Referring more particularly to the 
.special trouble of our correspondent, we may point out that 
a double dark slide that is well made in tie first instance 
xhould not develop leaks around the edges as tlie result of 
fair usage. If properly designed the two halves will so fit 
into each other that even a considerable shrinkage of the 
uiaterial will not let in light. If, however, from any cause 
this trouble does occur the first thing to look to is the hinge 
or hinges ; the effect of the shrinkage can often be remedied 
by taking off the hinges and refixing thpni after plugging 
the old hole*" with wood plugs glued in. The alternative 
n-t'thod of lining the rebates should only be resorted to 
when the re-setiing of the hinges and catches will not 
remedy matters, and then care must be taken not to use too 
thick or too stiff a material : otherwise the hinges will be 
badly strained and perhaps broken. Our correspondent 
use<l washleather, which is excellent if of the right thick- 
ness, but too often this material varies in'thickness, being 
much thicker in some parts than others, and tJien it is not 
very suitable. An excellent material for this and similar 
pur|x>»es is suede leather. A fine surfaced thin cloth is 
also very often useful, while even blotting paper is not to 
be despised. In fact, this last material is very useful, as it 
lan be obtained in various thicknesses, is very well adapted 
to the purpose, and lasts well if not handled too roughly. 

The most usual place for a light-leak is, however, at the 
light-trap where the shutter draws in and out, and as this 
tiap nearly always depends on a strip of velvet or plu.sh 
that in time becomes worn down a repair at this part is 
More often necessary. Moreover, similar light-traps exist 
in other parte of j>hotographic a])paratus, and so repairs of 
this type are often required. Sometimes cloth takes the 
place of velvet or phish, while very varied thicknesses of 
material are required to make equally good fits everywhere, 
and therefore it is advisable to collect odd bits of velvet, 
-rtoth, af plush, and keep them handy for repair purposes. 
V'anou.s thicknesses ;ire best provided for by mounting the 
material upon paper or card of varying substance; when so 
mounted it is easy to cut off strips as required. Beginners 
generally spoil the material at their first attempt by allow- 
ing the adh«*'ive to penetrate through to the surface and 
destroy the pile. If velvet is glued directly into the place 
prepared for it, usually a groove in the wood, it requires 
considerable care to avoid getting glue on the surface; the 
use of mounte<l material renders the task much easier. The 
paper or card should first be coated with seccotine or glue, 
and then the layer of adhesive smoothed over with a 
straight edge. The material is then rubbed lightly down 
and the whole allowed to dry under slight pressure. The 
grooves for the light-stopping material should be carefully 



88 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[January 18, 1918. 



prepared. The old velvet c;iu be torn out, and remaining 
fragments, together with the old glue, scraped away. Care 
must be taken not to cut into the wood and spoil Uie 
groove: hence it i.s best to use a scraping tool, and not a 
sharp-edge<l cutting one such as a chisel. The re-velveting 
of light-trajjs is a j)erfectly easy operation and a very 
necessary one that every photographer should be able to do 
for himself. It should not be forgotten tliat while velvet 
forms a good light-trap it is also an excellent dust traj) ; 
therefore, whenever it can be got at readily, it should be 
subjected to a careful regular brushing. A soft-haired 
toothbrush is good for the j)urpose. The brushing not only 
removes dust, but raises the pile, which is apt to be 
burnished down by the friction of the pai*ts which slide 
o\er it. 

Pinholes in bellows are troublesome defects, and the 
only effective way of dealing with them is to patch them 
from the inside with a ])iec6 of opaque black cloth. They 
can be prevented from a))pearing by keeping the leather in 
pliable condition. To do this a good dressing .should be 
occasionally applied, while the camera when not in actual 
use should be kept carefully in some place which is not 
liable to extreme changes of temperature. Further, it is not 
advisable to fold a caTuera tightly up and put it away for 
a long period. It is better to leave it just slightly ex- 
tended, but well wrapped up in a focussing cloth. Tight 



folding is very apt to cause the corners of the folds of the 
bellows to wear out, and these are most awkward places to 
repair. 

When overhauling apparatus all screws and brasswork 
should naturally be looked to. Loose screws in woodwork 
should be replaced by those a gauge fatter if possible, but 
if this cannot be done the old hole should be plugged and a 
new one made through the plug. If very loose a wood plug 
should be glued in; if only slightly loose a cork one will 
often do all that is required. 

Dead black is invariably required at regular intervals, 
even though the majority of ])hotographers neglect this 
very simple matter. In nine cases out of ten it will be 
found that a careful re-blacking of worn places will result 
in the production of cleaner negatives,' for reflected light 
plays a large part in fogging or veiling the image. An 
innocuous black containing no turpentine should be used : 
the popular one of lampblack mixed with dilute celluloid 
varnish is as good as any. 

Shutters also go wrong, but most of these are far too 
delicate things for the photographer to tiy ex]>erim'6nts 
upon. A roller-blind shutter is simple, and it is perfectly 
easy to fit it with a new blind, which is the repair most 
usually required : but focal-plane shutters and lens-shutters 
generally require experience and skill, .md should be put 
into the hands of exjierts if anything go3^ wTong. 



A LANTERN SLIDE=BOX FOR POSTAL TRANSIT. 



The safe transit of a set of lantern slides for lecture or other 
purposes to different pax'ts of the country is a problem that 
has i-eceived a certain amount of consideration from time to 
time. Several tj^jies of box can he obtained for sending such 
sets by can-ier or rail, but in oixler to afford adequate protec- 
tion to the slides from the severe handling parcels generally 
receive en I'oute, the boxes must Ibe somewhat heavy in con- 
struction and ibulky to handle. The cost of carriage therefore 





Lm 




^^^^BSS^'^^^^^^^^^^^^319 ^■ 


El 


1 


W^ '^ 



Fig. 1. 

amounts to an appreciable it«m, esijecially if they have to be 
sent any distance. 

Most attempts made to cut down the weight or bulk of the 
box result sooner or later in damage to tlie contents. 

The writer was asked by an oigaiiisation which sends a large 
numbei- of lantern slide lec-tures aibout the countiy to attempt 
some improvement on existing methods which, owing to the 
above causes, had occasioned trouble. 

The Parcel Post service suggested itself as a comparatively 
cheap method of transit, esiiecially for the longer journey.s, 
and it was necessary to ascertain if the limit of weight per- 



mitted the construction of a box that would afford sufficient 
protection for a reasonable number of slides. It was found 
tliat the majority of tlie lectures were composed of about sixty 
to seventy slides, ami this applies pretty generrally to the 
average lecture. Tliis numiber of slides weigli from 6 to 7 lbs., 
leaving a margin of fvoan 4 to 5 lbs. for the box, etc., to 
bring the whole witliin the maximum of 11 lbs. allowed by 
Parcel Post. 




Fig. 2. 

A box tliat was considerejl capable of giving suitable pro- 
tection for this num'jer of slides, also of sufficient strength to 
withstand the knocking about likely to be encountered on the 
journey and coming within the above weight, was designed. 
It is illustrated in Figs. 1 and 2. 

It is made up in ^-inch American whitewood, with all joints 
halved, glued, and dovetail bradde<l or screwed. The lower 
part is divided into four compartments, each of which is 
lined on the bottom and all four sides with j-inch wool felt; 
each compartment will take sixteen or seventeen slides, wliich 
fit in without any shake, and are well protected by the tiiick 



.Taouaiy 18, 191&] 



THE BMT18H JOURNAL OF PHOTOGRAPHY. 



29 



^1., ^).;^^ of felt all aronnd them ; sixty-eight slides are tiios 
aooommodated. 

The upper part has the interior lined with the same thick- 
nen of feit, and fita on in the customary manner, being held 
in position by four hardwood pina, in addition to hinged iron 
fltrkpa 1 inch in width at oaofa end. The upper part of the 
lid contains a separate compartment for holding the manu- 
script or descriptive notes, and is closed by means of an end- 
piet; affixed to one of tlie iron straps. A stout leather strap 
encircles the box lengthways, and, when fastenerl, secures the 
whole and forms a convenient handle for carrying. 

Provision is made on one side of the box for taking an 
arddress Ubel, which is 8ili|>ped into a recess when the box is 
open, and prevented from falling out by the act of closing the 
box : WBch a lahel c«n be reversed for nse when returning. The 
oatside dimenaons are 12i in. by 7 in. by 5 in. When filled, 
the weight complete just oomes within the limit of 11 Hm., so 
that it is neither bulky nor heavy to cany. It can he sent 
hy Parcel Post anywhere in the United Kingdom for Is. 

By payment of a registration fee of 2.1. in addiU.n, a certain 



security against loss is obtained, and it is much the best plan 
to do this. Eyelets are provided in the ends of the strap for 
inserting a piece of string or wire so that the ends can be 
tied and sealed. This not only gives security against the con- 
tents being tampered with, tut is necessary when the paix:el 
is registered ; such a box will be accepted at a post-ofRce with- 
out any additional covering or fastening. 

An experimental box was subjected to some pretty severe 
tests before being put into service to ascertain if it afforded 
sufficient protection to the contents. After being filled with 
slides it was thrown down a stone staircase and dropped from 
some height, but no damage was found to have taken place. 
Boxes have since been sent out on several journeys through 
the post without any breakage or cracking of the slides. 

A smaller box made on the same lines, having a capacity of 
about forty slides, weighs eight pounds, and can be sent by 
post for 9d. This meets the case of a lecture with a smaller 
number of slides ; and by sending out two boxes, one of either 
size, lectures of 80, 100, or 130 slides can be accommodated at 
a moderate cost for carriage. G. C. Weston. 



STANDARDS AND CONTROL IN CINEMATOGRAPH 

PROJECTION. 

IThe following psper, reoeniiy rend before the Kew York meeting of the Society of .Motion Picture Engineers, so admirably 
Applies methods of scientific measurenisnt, not only to cinenistogntph projection, butalso to that with an ordinary optical lantern, 
that it is deserving of a most carefnl reading, f t emboclies still another applicntion of the comparatively young science of the 
illuminating engineer to the improvement of the conditions under which we live. We feel pretty sure that not one cinema theatre 
in a thousand in this country ever thinks of measuring the illumination on the projection screen, and of adjusting it for the best 
optical comfort of the audience, to say nothing of the artistic presentation of the film pictures. Mr. Caldwell, after first drawing 
attention to the difTcrent types of projection sor«en, suited to theatres of difTercnt form, proceeds to set forth some approximate 
«tondards for the illumination of s cinema projection screen with the shutter open and no film in the machine. It is a compara- 
tively simple operation to make these measurements with instruments which have been designed for the purpose within the past 
few year*. ,\nd obviously the same control of what we may call the "bare illumination' of the screen— i.e., without the slide in the 
lantern stage — is advisable in the use of an ordinary optical lantern. The screen-illumination refpiires to var/ according to the 
transparencies which are being shown. For example, Autochromes will do with u screen illumination which, in the case of 
ordinary sUdes, would cause ilisconifort. Further, the paper discusses improvement in illumination and in the avoidance of flicker 
by the use of a tungsten lamp in place of an arc as the source of light Hds. " H..T."] 



Tbb subject of light-intensities for motion picture proje. -. 
tion, is one ol rery real importance, but concerning which 
there is a scarcity of data. 

First of all, it is of intstest to note that the eye sees a 
picture on the screen not by the light which strikes the 
•areen, but by the light which the screen reflects to the eje. 
If we imagin* a perfectly black screen— one which reflects no 
light at all — we see at once that, no matter how strong the 
beam we project on the screen, we will obtain no picture at 
all. ^icr«ens used in practice vary in reflection factor— that is, 
in their power to reflect light, through very wide limits ; henc« 
it is obviously necessary to consider the reflection factor uf 
different icreena when discussing acreen intensities. Nor is it 
correct to assume thst the acreen which reflects the highest 
psocentage o( the light striking it is necessarily the best 8cre«n 
to nse, for the manner in which the reflected bght is dis- 
tiibnted is also a factor which affects the brightness of the 
pictonb For example, it is possible to conceive of a screen 
tsilioh reflects a very large proportion of the light striking it, 
yet which, due to the fact that it distributes the reflected 
light far out to the sides, is actually less satisfactory than one 
iriiich reflects a lower iwrcpntai;.- >l the light striking it, but 
which confines its reflected liglit within useful angles. 

From the standpoint of their reflection characteristics, 
aereens in common use may be divide<l into two classes :— 

(1) DiRuse Txflecting screens , 

(2) Spread reflecting screens. 



Of the first class, white cloth screens and plaster screens 
are tj-pical. A white cloth screen, when clean, can be made 
to reflect as high as 70-75 per cent, of the light which strikes 
it, and a plaster screen 80-88 per cent. The light is reflected 
at wide angles, as shown by the diagram Fig. 1. Such screens 
are well adapted to theatres in which the position of the seats 
with respect to the screen is such that the picture must be 
viewed at relatively large angles, for no matter from what 
angle the screen is viewed, the brightness is the same because 
of the way in which the light is refle<;ted. 

Aluminiumised screens and ground-mirror screens are 
examples of the spread reflecting class. A clean aluminiumised 
screen can be designe*! to reflect about 60-65 per cent of the 
Ugj^jiigiking it, and will confine the reflected light within an 
angl» of approximately 30 deg. Ground mirror screens when 
clean can be made to letlect approximately 80-90 per cent, of 
the light and confine the light within alx)ut 30 deg. Such 
screens are well adapted to theatres in which the seats are so 
arranged that the picture does not have to be viewed at large 
angles. 

Fig. 1 shows the relative brightness of matt, metaUic-suriace, 
and ground-mirror screens when viewed at various angles. 

Allow me to emphasise the point that the reflection factors 
I have mentioned assume a clean reflecting surface; a very 
slight accumulation of dust can reduce the screen brightness 
very materially. I belie\-e that with a sche<Iule of regular and 
frequent cleaning theatre managements can in many oas«9 



30 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[January 18, 1918. 



increase their sci-een brightness by fully 50 per cent, of their 
present average values if they desire to do so. 

Thus, it is sure tliat the intensity of the beam project**! 
determines only relatively the brightness of the pictuiv. 

Uniformity of screen illumination is another factor which 
musit be considere<l in connection with screen intensities. It is 




" AfcrALLic SoKi'/icc ScaetM 




Pig. 1. 

not uncommon to find screens upon wliich the intensity ne;ir ihf 
centire is several times the intensity near the edges of the 
picture, or where the intensity on one-half of the .sci'^cn is 
mucJi higlKi' than upon the other half. When this condition of 
non-uniformity obtains, certain portions of the picture are, of 
course, brighter than others, and while the eye cannot readily 
detect small differences in bi'ightness, the fact remains that to 
say a screen is illuminated to a cei-tain average intensity is 
not definite when a wide difference exisits between mininuim, 
average, and maximum intensity values. Good projection re- 
\juires a screen intensity approaching uniformity, and th" 
nearer the intensities at different points oome to being equal, 
the better will be the projection from this standpoint. The 
uniformity of intensity at different jioints on the screen is 
affected by the condenser design, steadiness of the liglit, and 
by i^tinement in focussing adjustment. 

Another factor which we must consider is extraneous light. 
Obviously a higher screen intensity is required in a theatre in 
which daylight is allo^ved to enter, or where lights are kept 
burning at all times, than in one where all ithe light comes 
only from the projection ajiparatus. The effect of extraneous 
light is to decrease the contrast between the high lights antl 
low lights on the screen. If, for example, the intensity of the 
beam in a low light of the film is, say, 1/50 of a foot-candle 
at the screen, and in the high lights the intensity is, say, 
■2 foot-candles, the contrast is 1-100. If upon the sci-een image 
is now superimposed an intensity of 1/10 of a foot-candle, due 
to extraneous light, the contiaM becomes approximately 1 to 
17. From this it is apparent that even a veiy low intensity of 
extraneous light calls for considerable increase in screen inten- 
sity if good contrast is to be secured. 

Before leaving the subject of contrast, I wish to mention 
that film-jiroducers are endeavouring to a greater and greater 
extent to jirovide the proper degree of contrast in their films. 
Alore and more care is given to lighting their scenes in such 
a way that with a projecting beam of normal intensity the 
proper gradations of light and shade will appear en the screen. 

The use of tintetl and toned film is becoming more extensive. 



This tinting and toning serves two i>ur2>oses : it lends colour 
to the scene, and it reduces ithe intensity. Usuallj-, the iM'o- 
diicer has both of tlies^- effects in mind. He uses a blue tone, 
let us say, to pw-tray a moonlight scene. The colour gives the 
observer an impression of moonlight ; the producer intends in 
all probability that tlie low intensity shall help in furthering 
this impi-ession. If then, the operator, seeing that the picture 
is not perfectly clear, sends a i-ush of extra current through 
his carbons he kills to an extent the impression that the pro- 
ducer hoped t-o convey. I have talked with producers who con- 
sider tliis natural tendency of the operator to be a matter 
worthy of no little consideration. 

Data which I have obtained on the transmission of samples 
of tinted film may be of interest. 

Percentage absorption of light by various tints of films : — 

Film. Per cent. 

Black 9 

Yellow 21 

Light amftxM- 22 

Heavy amber 33 

Light blue 33 

Dark blue 40 

Green ^3 

Purple ^2 

Orange ^^ 

Red 79 

The illumination on the screen with the shutter stationary 
and no film in the machine has been taken as 100 per cent. 
The values for the tinted samples ai-e given in percentage of 
light-absorption due to the different tints. The values given 
in the table represent tests on a single sample of each tint. 
and while these saiajdes are believed to be typical, others 
might, of course, show somewhat higher or lower values. 

In vie^v of the foregoing general discu-ssion you will not be 
surprised when I say that suitable intensities for motion 
picture projection range probably from as low as 2.5 foot-candles 
to as high as 30,* depending upon local conditions. I do not 
think that 2.5 foot-candles is sufficient for the projection of a 
dense film oni a dusty muslin screen ; neither do I think that 
an intensity as high as 30 foot-candles is desirable ha- a light 
film projected on a higlily selective or spread reflecting screen. 
I know of cases where theatre managements have been forced, 
through the complaints of thein patrons, to reduce the inten- 
sities they were employing from a value near the upper limit 
of the range I have given to a considerably loAver one. If 
muslin or plaster screens are used, and these are faithfully 
kept clean, I believe an intensity of 5 foot-candles should be 
ample for the projier jnojection of all except vei-y dense films. 
If an aluminium-size<l or ground-mirror sci-een is employed a 
value of 2^ foot-candles should be ample. A great many 
theatres are projecting pictures with less than 3 foot-candles, 
using a plain sci-een, while the largest and best-known theatres- 
are obtaining less than 10 foot-candles on a plain screen. t The 
distinction between dense films and tinte<l and toned films is of 
interest. In the former, ithe density is due to variation in 
exposure and development, and is not as a rule obtained with 
a definite purpose; in the latter, the purpose is to lend colour 
to the picture and to control its brightness. I believe that an 
intensity of 5 foot-candles on any good, clean screen will be 
sufficient for the projecticm of any film sent out by a competent 
producer, and I also believe that no discomfort will be expe- 
rienced from intensities in the neighlwurhood of 10 foot- 
candles. In giving these values I pre-suppose the intensity 
due to the general illumination of the theaitre to be of a very 
low order and assume the measurements to .be made with the 
shutter open and no film in the machine. As I have previously 

Gage, 8. H. * H. P. " Optic Projection." 1914. 
I Optic Projeclior, J. A. OlBPge. Tlan> . I. E. S., Nov., 1916. 



Jaiiaarv 13. 19ia I 



THE BRITISH JOURNAL OF PHOfOGRAPKV. 



31 



' ■■ " 1. tl>c effect 'if extiaiie. .ii> light in decreasing the 
.:. V of a |iicture is very niaiktil. 

In this meeting we are intPievie.l in projection apparatus 
only in fo far as the cfiiniKtnent pai t- of the two systems, arc- 
lamp and Mazda lamp, affect screen intensities. I shall dis- 
cuss these two systems very briefly from this standixiint. 

Fig 2 sbow« the arc-lamp >Tsteni as it is now, and as it has 
been for a number of years. The li'.'ht-intensitv at the screen 



CoBdcntliic Lou 
Fir* Shutter '< 



ScFMa 




with any »y*teni i», uf cour»e, dependent upon the light given 
off by the ••>urce. and with both arc-lamp and )faz«la lamp sys- 
tem* the light which the sourc? gives off is dependent, but not 
in equal ratio, u|Kin llie current which flows. The condenser'i 
in all arc-lamp systems must be lornte<l at a considerable dis- 
lsn«> from the <ource, chiefly because of the intense heat of 
and manufacturing considerations limit the sizes of 
- to the point where, as you will note, the angle <ir 
/one subtended by the c«>nden««r with respect to the arc is 
omall. With direct-current arcs this is not so great a handicap 
as with alternating-current arcs, for the direct-current ai-c 
*' • ater ]K>r4ion of thf light it generates forwanl. 

- used with arc-lamp e<]uipnient lue nuuU' small 
:•-! -Aith respect to their f'n-al length in order that 
I if. in tlH» arc will not be annoy ingly apparent on 
u. There is a |M>ssibility of increasing the screen 
•. . with arc-lamp apparatus by increasing the a|>ertare 
of the objective lens, but under present conditions such an 
increase would be likely t<> be obtained at a sacrifice of steadi- 
ness in the illumination of the pi<-tiire. There s<-ems tt> be a 
(M^^sibilily of ittrreasing the inten»ity prodiicerl by direct-cur- 
rent mnchini". hy mor<» careful d-'-i'-'M of thf shutter and |«>s- 

It is iloubtful 

'■■'•■■ •■- can be miirh 

liie c<:ioling of the carbons is »<i rapid that 

-'.■ :- , - ' ..1 ^t is likely to be encountered. This effect is, 

■ >! course, very marked where 25-cycle current must be use<l. 







Fig 3. 

You will n^ile that with the Ala/da lamp system. Kig. 3, a 
mirror can be used to re-fiirect into useful directions the light 
which the lamp gives •>!! in directions .away from the omdeiiser. 
The use of this miimr increns<rs the illumination on the screen 
' '75 jer cent. Tlte lamp is so designed that 

lit IS thrown off to the sides, that is. a rela- 
' "f the light either strikes the condenser 

I ■ ily by reflection from the mirror. The fact 



that the liglit-souree is cunfineil witliin a bulb eliminates 
danger of cracking the condenser, hence a short-focus condenser 
which subtends a. large angle can be utilised. Through the 
design of a »i>ecial prismatic condenser the necessity for a 
thick and heavy lens with accompanying aberration is 
obviated. The fact that the light-source is absolutely steady 
and without noticeable flicker, even on 25-cycle current, permits 
the use of a wide-aiierture objective lens with an accompanying' 
good utilisation of light. Shuttei-s can be designed to opera-te 
very effectively with Mazda equipment because of the fact that 
the filament, being heavy, does not get a chano? to cool between 
current reversals. When arc machines are being adapted to 
the Mazda lamp, it is of advantage to bear the point in mind 
that the shutter can usually be improved. It is due 
s.dely to the better utilisation of light that the Jlazda lamp 
— a stiurce of lower brilliancy, and far less energy 
consumption than the aic--can be usetl to project satisfactory 
motion pictures. 

For many years the arc-lamp has been jiractically the only 
light-stiurce used in motion-picture projection work, and higher 
and highcir amperages have been employed as the size of 
theatres has increased, and as competition between theatres 
has become* keener. It ap])ears that a reaction from the 
verj- high values may be logically expected, for a brilliant 
picture loses its attractiveness when discomfort and eye stiain 
from glare are experienced. A bright screen viewed against a 
dark backgnmnd produces an effect similar io that produced 
by a bright street light viewed against its background. In the 
first case the effect is less marked, and may not be attributed 
t" contrast in brightness, and for this reason is probably 
more serious than if the trouble were recognised at once and 
correcteil. Flicker and a/ic travel are also more pronounced at 
high intensities tlian at low ones, and we may, therefore, I 
believe, ex|>ect to see the higher intensities gradually aban- 
doned in favour of intensities of the lower order. 

J. T. Cai.dwei.l. 



DEATH OK Mit. f. H. HEWITH'. 

One .if Ih; w-.>ll-Uao\ui you:i7er figurea in pl'otoi^raphic circles has 
been iomo\ed by t,he Jeatl'. on Tuesday last, .January 15, at Elstree, 
Hertu, of .Mr. C. H. Hewitt, at tlio a*re of 45. .Mr. Hewitt had 
iM-en ill ill health for two years past and had had to relinquish his 
I>"< tion of depotyprincipal of the Photographic Scfliool at the 
I!. ,;('iil Street Pdjtechiiic. He nevertjieless was actively engage'l 
on photograpliio Irtorary woik up to witliin a fi^w days of his deatlli. 
Wd ourselves received u letter from him as reL-eutly as Saiiirday 
1a«t iftiaiiking us for some slight service we li»d been aJble to do 
him. 

.Mr. Hevitl's was one n' the somewhat iimnial careers in which 
ik man brought up as a professional photogj-aplicr Ima braudied out 
ill tha diretti<;ii of embracing the interests wliich are conimouly 
tlis oj^actc ■ istic of the amateur photographer. He was the pupil 
-.. j) y—tf- of Mtasrs. H. P. Rohiiuuin and Sou, and for nine 
years himself carried on i' business of jihotogiaphic portraiture at 
f!i.te«he.id-i-n Tyne. This he relinquisliejl in order to join the staff 
oi Blio Polyteolinic School as chief assistant to Mr. Howard Fanmier, 
a (losition which he hcM for n number of years, and iii which he 
achieved a reputation as a pictorial photographic worker diiefly in 
tho Imimoil process. Aiiait from his teaohii»g activities at the 
Polytechnic ho was an iiidefatigallde contributor to tlic photographic 
I less, IjT the most part .-.i onymously. This work, after leaving tho 
Polyiedhiiic, he continiie.l to do. with the most heroic disregard of 
pjivsical chstadei. whi<h were the coii8e<iueuce of his illness. His 
deatli will liu regretted hy the photogra.pliic cojr.munity generally 
aiid still more particularly by the many students of photograjihy 
»ih<i ciHno under his inlhience. 



32 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[Jaiiuaiy 18, 1918. 



jisslstatits' Rotes. 

yotes by ufistants suitable for this column will be congidtrtd 
Ktnil paid for on the first of the month following publication. 

Copying Architects' Plana. 

Some time ago a correspondent pointed out in the pages of the 
■" B..J." the Krge amount of work that may be done for architects 
4»nd builders in the near future, having in mind the 30,000 houses 
to be erected under the auspices of the Government as soon as peace 
is declared. Exteriors and interiors were in the mind of this cor- 
respondent, but the happy days of peace, as well as the orders to 
photograph the new houses, thougli nearer, seem to be a very long 
way off. 

The opportunity of copying plans for architects is, however, now 
-with us ; some of us are busy on the job, while others have made 
no bid for the worU. There are now about 6,000 registered architects 
in the United Kingdom, and many of them are busy with plans for 
the new houses that are to come, especially as the Government has 
instituted a great competition, with handsome prizes for such plans, 
A contest which closes in a few weeks' time. 

It is not my intention to describe in detail the methods of copy- 
ing plans, but rather to point out two things which may be of 
assistance to those workers who have a mind to make a bid for the 
•work, or who desire to make a really good job of an order should it 
<ome along. In the first place the worker should be well acquainted 
with blueprint and other processes of a similar character used for 
(>lans. 

There is another thing the would-be specialist in architectural 
plan work should know, and this is the architect's usual method of 
indicating materials on working drawings. It has been the custom 
to colour some plans, the said colours indicating brickwork, con- 
crete, etc., and obviously such plans are not particularly suitable 
for the camera or the iron processes. Other architects use hollow 
squares in which are written the names of the various materials. 
The Office of Works, I believe, still use the hollow-square system, 
^nd colour up when the working drawings are passed for the builder. 

Naming and colouring, however, appear to be going — ^happily for 
ihe photographer — out of fashion, and the majority of architects 
are adopting a kind of " shorthand " which has been imported from 
America. It is not yet in common use, but it will be, as it does 
*way with colouring, is equally effective, telling the same tale, and 
«asier for the architect, and for reproducing by the camera, or by 
vontact per the blue print or other iron-printing process, artists' 
Alack ink being the only " colour " used upon the tracing medium. 

The accompanying sketch shows the marks used by architects to 



Patent ReiDs. 




'indicate vai-ious materials upon their plans, and a knowledge of 
-them on the part of the photographer may assist him in getting and 
Kiarrying out the work. The eleven marks are :— 1, brickwork ; 2, 
plaster ; 3, cast-iron ; 4, concrete ; 5, lead ; 6, wrought-iron ; 7, steel ; 
■8, stone; 9, brass; 10, timber, sectional; 11, timber, longitudinal. 
These, it will be noted, very much simplify the task of the photo- 
grapher. — P. U. S. 



COMPLETE SPECIFICATIONS ACCEPTED. 
f7i«M specifications are obtainable, price 6d. each, post free, from 

the Patent Office, 'J5, Soutnampton Buildings, Chancery La?i*, 

London, W.C. 
fhl date in brackets is that of application in this country ; or 

abroad, in tlus case of patents granted under Vie InternatioruU 

Convention. 

Developinr Cinematograph Film. No. 111,136 (Nov. 14, 1916). — 
The film strip (prefei'a.bly having the usual perforations) is passed 
through the ibaths or drying chambers in loops which are weighted 
at their free ends to take up expansion oif the film due to wetting 
and which (at their end.s opposite to the weight) are passed (pre- 
I'erably outside of any itath employed) over rollers having means 
.such as pins at each edge which momentarily engage the per- 
forations. 

In order to obtain a long travel in a tank the film may paes 
from one roller down into a loop up to another roller side by side 
with the first and on the same shaft and so on to tlie width of 
the tink, each loop being suitably weighted. 

.\lbo where the film leaves one bath to pass to another 
or leaves on« set of rollers to pass to another which it 
would usually do in a hoiizontal or perhaps inclined direction', 
means are provided to take up the slack caxised by wetting, sudi 
ifor example as by allowing the weight in the last loop to act for 
this purpose by emploj'ing a plain exit roller for the bath, and 
a film-holding or pin-toothed roller for the entrance of the next 
(bath, whereby the last weight effects the desired stretch over all 
the film up to the entrance end of the next bath. 

The weight carried by each loop is preferably a roller which 
can rotate freely as the film travels, such roller having guide 
flanges to keep it in place. Such weight acts not only to take up 
expansion when the film is wet but allows for contraction in the 
drying of the same. 

The several parts of the plant (as shown in the drawing), ocou- 
jjying three small rooms — ^thedark room 1, washing chamber 2, and 
drying chamber 3 — ^will be described in the oixler in wliich the 
film passee through them. 

The spool 4 carrying the exposed undeveloped fiJm 4-'< is placei 
on the spindle 5, the free end is connected to a film already in the 
machine and is passed through an adjustable gate 6 by means of 
which the pressure on the film may be regulated. The film passes 
from the gate around a pin .spool mounted on the driven sluil't 7 
and forms on the underside thereof a loop 8, which is weighted 
by means of a spool 9, arranged so as to rota.te freely as the film 
travels. Such spool ia provided witJi deep flanges to keep it in 
place. The film then passes over a plain spool, or if it is desired 
to have more than one loop in the same bath, over as many more 
pin s|)ools on the shaft 7 as may be desired, each loop formed being 
weighted with a spool 9. 

The loops 8, with their weights, are immersed in the developmg 
bath 10, and the number of loops or length of film determines the 
time taken by the film to pass, through the developer, assuming 
that the travel is maintauied constant. The film, as it leaves the 
(bath 10, passes up and over a plain spool 11, but in order that the 
film may pass horizontally to the next series of spools on the shaft 
12, the plain spool 11 miay be disposed horizontally w itJi respect 
to the series on the shaft 12, on a supplementary shaft, as shown 
at llx by dotted lines, but this is optional, as the film may pass 
directly from the plain spool 11 to the first toothed spool on the 
shaft 12. From the spools on the shaft 12 the film passes in a 
loop or loops, weighted as before with a spool 9, into a bath 13 
for washing the film. From the plain spool on shaft 12 the film 
passes to the first toothed apool on a sihaft 14 from wliich it hangs 
in loops, weighted as before, in a fixing bath 15. In order to 
provide for tlie complete fixation of the film a second shaft 16 with 
a further series of spools and loops may be jirovidcd, and, from 
this last series of spools the film passes either directly to the 
spools on the shaft 17, or as shown by dotted lines over the plain 
spool 16t, to the wa.shing chamber 2. The weiofhted loops from 
this series of spools are su.spended in the washing bath 18. Float- 



Januar}- 18, 19iai 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



33 



TTTj-rr,-^ ^ ,,,.... , .-r,.,.^^ . .,,f.\..,-.,,> • II, 1/J'l .•.J.-:.-^// 



^ 



\i^: 







ing on lh» aurfare of the Iwth aiid liiraUd lirtwfen the two inner 
f .. — ..( .i,_ I. ,.. ,|m j,_ j|„ nonsennitiaed aide, U a bar or Tuller 
<>h'loatlipr or other deaircd material for cleanini; 
i..r .«. „ ..i L,,r ij^m, the >ize of thi* bar or roller being inch that 
it i* cauaed to rotate br the rubbing action of the Kim againat it. 
To anift further in the proper waiihing of the film, a fpraying 
davicre aO i> provided above the spooU on the Khaft 17, the water 
therrfnim niiiiiing down the lilm. 

An it j* frrquentlj' desired to tone or atain the film, after waih- 
ing. the tilni may paaa to a farther wriaa of apool* on a ehafl 21 
and be »rran({ed to hang in loop«, weigblad a« before, which l««4)» 
ma> l« immeraed in any detired toning or ataining bath 22. Th-- 
lilm iMj.> i'i«.«ea to a further M>ri«« of K]MX>!a on a nhaft 23, located 
'I in ill (Muaagc it may pann betwern 
24. 25. tx>verMl with an niMurbent 
ii]> «oroe of the water or other 
-•1. "Uch rollem are not however 
A. I..:. .re llie .'iliii >.'• <aiL»rd to bang in I'lojm from the 
■.irift 23. weighted a* bofi.re. Near the Uatom of the 
kio|i a dry > i-li leather covered rol'.r 26. which may be fixed or 
rauv I to pitiitr III the rever»e dire. t..m lu the travel of the fa.m. 
i» mpjN.rtMl ni inv (li« r.i) niaiinrr between the lonjw for the 
fnxrf'»r of |N.ii,|i ng tl„- i.'.ii trij^iitri lidc of the fi'm. from 
the 'juHiU on »haf( 23 the film ma\ fiaiia to a further *erie* of 
apuoU on the »haU 27 hangnig tlirn-from in lao}w a« before. 

Hi>( air i< lira. til into the drying liMnber 3 by meant of a fan 
28 anil rttrarifil l>y a *erofid fan 29. 

Fn>ni the . Irving rhamlier the illm (Huan to the nfxjol 30 in a 
Hninheil c<Midition. 

A> loon aa the film on the »|>ooI 4 in run out the free end of a 
Afaa am a tecimd apciol 31. mounted on a ^lindle 32 arranged 
directly below the .•pindle 5 may be ronnacted to the end of the 
Aral H!m and no on. it being advifaiile. aa will be readily under- 
•tood. alway* to keep a length of film, preferably a iipoilt length, 
in the machine m aa to art aa a gnide and to aave any further 
handliitg of any film onre the machine haa been in operation. — 
Willmir Cecil .Jmimib of 76 and T3. Wardoar Street, I^Miduii. W. 



in the .1 
• piir 

materia ;. 
liqui<l » it)i 
ea«eiitt'il. 

flptXiU "H 



FORTHCOMTNO EXHIBITIONS. 
Pebrmry 21 lo 23.— Leicester and I^iceKtemhire Photographii 
Society. See., H. C. C:roea, 80, Harrow Road, Leiccater. 



meetings or Socletlesa 

— • — 

MEETINGS OP SOCIETIES FOB NEXT WEEK. 
SATCao.tr, Jaxiarv 19. 
Roriley aad Oiilrlct Photographic Society, Lantern Lecture on Yorkshire. 

MoXDAT, JaNIARV 21. 

Booth Loudon Pbotocnphle Hocieiy. *' Garden Photography " A. D. Fort. 
I>rw>harT Pholoaraphic Society. " Photoirraphy and Focus " Prize aiiiles. 
Bradford Photoarapblc Society. " Carbon Punting." J. H. Leighton, 

TUEISAV, jAXr ART 22. 

Royal Pbotocraphie Socieiy. "The Manipulations which go to Successful 

Picture Making." R. H. Ijawton. 
birmlnghaiii Photographic Hociety. " Sea, Lake and Cloud." W. H. 

Uidlake, M.A. 
Ilanlay Photographic Society, Y.M.C.A. I.«noaahlre and Cheshire Union 

Portfolio. 
Htalyliridge Pholorrapbic and Beientiflc Society. " Summer Days with the 

Birds in the Country." F.Taylor. 
Hackney Phoiographio Society. "Display of Architeetnral Prints." H. R 

Heath. 

WKDXKSnAV, Jam'ary XS. 
Croydon Camera CInb. "Batista Printing Paper." W. H. Smith. 

TnCRSDAY, Jari .tiiv 24. 

I.irennol Amatonr Photographic .issociation. "Some 1...A.P.A. Memories." E. 

R. Dibdin. 
Hull Ptaotographlo Society. Comnu-ison of Band-Coloured Slides of Mr. F. 

Woollons with Pagetaanil Aiitochroinea. 
HoddaraAcH N'alnratint and Photographic Society. ** Tlie 1 omes and Haunts of 

WB rthaorth." P. I.,iind. 
BtaakjocaiVatographic Society. Exhibition of Work by Mciubera. 
Sunderland Photographic As-ociation. Aftlliation. Lecture. 
Hammemnlth I Hampshire lloiisei Plioiographic Society. "After Work on the 

NegsUve and Print." C. C Wenton. M.I.E.B. 
Rodlry and District Pbotographic Society. Membera' Night. 



ROYAL PHOTOGRAPHIC SOCIETY. 
.MjfrriM; he'd T»e»d.iy, .]r.nii;iry 15. Mr. Olaf Blooh in the chaii-. 

.Mr. Ctiinberlaiid Ckiike delivered a Imitern ledtiire on 
" .Shakespeare and the .St<ige," in wLioli he deaiU witJIi the 
ini|.er8.;iiatorR of .Siiake8)er..»nn clioractcrs fiom the earliest, such 
as Hnrbnge to thofie of the jnegeiH day. He IlliiMrated his paeein^^ 
bioj^nphicat! commentary by portraits iiiid repioduitioiis of stage 
r?ent«. 

On Uie pix>poaition of the chaiitiian a vote of lliaiik» was heartily 
acfoidf'l to thu lecturer by accjamatioii. 



34 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[January 18, 1918. 



CROYDON CAMERA CLUB. 

Mb. a. F. C.\th.\bine gave a practical demonstration on " Enlarg- 
ing on Bromide Paper," wliich proved to be an excellent one from 
the beginnin's point of view, and interesting also to those who had 
attended similar expositions more times than they cared to remember. 
He used the club's enlarging lantern, and thus saved himself the 
trouble of caiting his own apparatus along, and the necessity of 
refusing hot baked potatoes to rude boys in transit. The club 
lantern is fitted with a Bray " inclineoJ " inverted gas burner, not so 
well known as its merits deserve ; a 9 inch condenser for half-plates, 
and an objective of the Petzval type. Considering that this type 
followed the early slow landscape lens working at about /'/12, it is 
wonderful how it has maintained its position for portraiture ; but, in 
Mr. Catharine's opinion, and most others, its proper position is not 
in front of an enlarging lantern for all-round work. Even a quarter- 
plate in the carrier showed a falling off in definition at the corners; 
a half-plate would have told a far sadder tale. He used a commer- 
cial ruled glass for the test, but Mr. Claypoole reminded members 
of the old. and, periiaps, letter, device of ruling lines with india-ink 
on a fixed-out dry-plate. The india-ink invariably breaks up, and 
the minute fissures permit of the finest focussing. 

The demonstrator having explained elementary but necessary 
matters, made three enlargements from three negatives on Welling- 
ton's B.B. bromide paper, the exposures being regulated by guess- 
work. Had he paid for the paper in the ordinary course, doubtless 
he would have hein more careful. Nevertheless, three really fine 
enlargements of a rich, warm black resulted, which were much 
admired, for Mr. Catharine is one of a very select few in the 
club who can make a good combined portrait and picture. Though 
much slower than tlie average bromide paper, the B.B. brand appears 
to be fast enough for most purposes, the three-quarter plates enlarged 
on to 10 by 8 paper being given about 1^ minutes' exposure. 

Generally, he ascertained the correct exposure by trial in the 
usual way, but strongly recommended Sanger Shepherd's density- 
meter, provided that the right high-density (in which detail is just 
to be recorded in the print) was selected. Some discretion was re- 
quired in the selection, for in tlie case of a portrait it might well be 
that if a white collar were taken it might mean an over-exposed 
print; a little experience soon taught one all that was required in 
this direction. Tlie figures in the table supplied with the meter, he 
said, were in all cases given in the nearest whole numbers to any 
outstanding fractional numbers. Here Mr. Catharine amused him- 
self with the blackboard, and conversation became fairly general. 
One gathered from the latter that whisky is now being sold 50 per 
cent, under proof — a criminal proceeding, and from the blackboard 
tluit the lecturer had taken the characteristics of the series of num- 
bers, which were in geometrical progression, and had worked out a 
constant factor of 1.2599 (approx.), conducive to greater accuracy. 
When this fact had soaked into the 50 per cent, under-proof gentry 
(mostly of the rule-of-thumb sort), he began to experience a lively 
time, and ultimately was dislodged from his position by .0001 pre- 
cisely, it being generally considered that 1.26 was sufficiently accurate 
for exactitude gone mad. 

However, the lecturer revenged himself on " R. C. B.," who, it 
appears in a recent article in "Photography" on enlarging for 
beginners, has said as follows : — " It is sufficient to treat the influence 
on exposiue as strictly proportional to the area over which the light 
is spread. Thus, if on one occasion we make an enlargement twice 
(linear) the size of the original, and on another we make it three 
times (linear), the exposure in the two cases, everything else being 
equal, should vary in the proportion of 4 to 9, since in enlarging 
twice we have an enlargement of four times the original area, and in 
enlarging three times we have one nine times the original area." 
With his enlarger, Mr. Catharine had found the ratio to be 4 to 7, 
which he considered too big a difference to be ignored for the sake 
of simplification. To one accustomed to think in several places of 
decimals such a discrepancy must be very painful, and R. C. B. is 
respectfully requested to be more careful in future, even if beginners 
have to be sacrificed in consequence. That he is familiar with the 
point at issue, of course, goes without saying. This is merely men- 
tioned to avoi J any possible inference arising to the contrary, which 
obviously would be an unwarranted susuestion. 



Commercial ^Cegai imeiilaetice* 

Leg.\i, Notices. — Notice is given that the names of the under- 
mentioned companies have been struck off the Register of Joint 
Stock Companies, and are dissolved : — County Photographic Co., 
fjimited; Fac-Simile Art Co., Limited; Magnet Photographic Paper 
Co., Limited; Photo .^rt Co., Limited; Summit Colour Engraving 
Co., Limited ; Colour Photography (Foreign Patents), Limited ; Eng- 
lish Fine Art Co., Limited; Lewis Photographic Printers, Limited. 

Wh.^t is " TirK Whole of a Basement " ? — At the Bath County 
Court last week, before his Honour Judge Gwynne James, an action 
was heard arising out of a dispute between landlord and tenants. 
Tlie plaintiffs were Jlisses Chivers and Joll, photographers, and the 
defendant Mr. T. J. Head, dental practitioner, both of Seyinour 
Street. The ladies, who rent premises from Mr. Head, and adjoin- 
ing those occupied by him, claimed the exclusive use of all the 
cellars in the house, and asked for an injunction to restrain the 
defendant from using any of the same. £5 damages were claimed. 

Mr. F. R. Wo.ifherly appeared for the plaintiffs, and Mr. A. 
Myddelton Wilshere represented the defendant. 

Mr. Woatheily ex) lained that opposite the Midland Station two 
liouses, both owned by the defendant, adjoined ; one he occupied 
liiinself and the other was formerly occupied by Mr. Lewis, a well- 
Unowii photographer, who had to close bis business owing to the 
war. Consequently the latter was vacant for some time. .Miss 
Kathleen Chivers, who had been for many years in the photograohic 
business as an assistant in London and Bedford, entered into a 
partnership with Miss Marion Joll, o£ Bristol, to start in business 
together in some town where a suitable place could be found. The 
premises in question attracted them, uiasmuch as the landlord's 
wife was Miss Joll's sister, and they were previously used for the 
express purpose for which they required them. They eventually 
agreed to take the same. Not merely on the terms of the agreement, 
"out in fact, they were to have the whole of the basement, and their 
exclusive right* began from the top of the stone stairs. Now, Mr. 
Head had let the higher floors to two tenants, Mrs. Matthews and 
Mr. Curtis, and in order to get himself out of a mess he was in- 
truduig on the plaintiffs' basement by depriving them of two of the 
cellars to enable Mrs. Matthews and Mr. Curtis to store their coal. 
One of these was used by Mr. Lewis specially for enlarging, and the 
plaintiffs could hardly have balanced their camera on :Mrs Matthews' 
coal, not te mention the dust. (Laughter.) 

The Judge said the question appeared to be what was the meaning 
of the term " the wliole of the basement." 

Quite a volume of correspondence was read, and Mr. Wilshere 
remarked that there had been a great deal of friction between tht: 
parties. 

The Judge at this stage suggested a visit of inspection. Before he 
left to do so, accompanied by counsel, Mr. Wilshere remarked that 
defendant was perfectly willing to make any reasonable arrangement. 
On their i-eturn. Miss Chivers said that defendant told Miss Joll 
and herself that Mr. Lewis used the whole of the basement for the 
i.botographic business, which was an inducement to them to rent the 
premises. Consequently, on bei-ig deprived of the two cellars, plain- 
tiffs had had to pay for the use nearly every week-end 
of a dark room at Bristol for enlarging Defendant's attitude was 
that the premises were his and he could do what he liked with them. 
After Miss JoU's e\idence the defendant went into the box. He- 
said this was the firs:; time he had ever heard the plaintiffs required 
the cellar for enlarging. He would have been willing to allo^v them 
to have it then and now. In speaking of the basement he never 
included the two cellars in his meaning. He added that on the 
arrival of Mi-s. Matthews he asked Miss Chivers which cellar she 
vi'&nted. Ho proposed to let eadi tenant have a cellar. 

Other evidence was given by Mr. Arthur A. Gooding, of Gooding 
Bros., who considered the cellars were not part of the basement, by 
^Irs. Matthews, and by Mr. Curtis. 

The Judge, in giving judgment for the plaintiffs, said it was clear 
the whole of the basement meant and included the cellars. He was 
not satisfied that leave and license was given to the tenants to use 
the cellars. The niaintiffs succeeded because there had been tres 



Janoao- 18, 1918.] 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



35 



l>ata, but the ciaim. like the agreement, waa not altogether explicit. 
BecauM the plaintiffa' claim wai in rt-ference to one cellar only and 
not that uied for enlarging, the damages allowed would be techiiic.il 
Jamat^es only, via., la. He refused an injunction, because he 
thought it wa« unnecenary He hoped Mr. Head would not prevent 
iinyone uaing the cellars in future. On the question of costs, lie 
■^ve them against the defendant on .Scale B. " L«t there be no 
more fiisa," added hia Honour. 

NEW COMPANIES. 
F.\Rgcn.ui Vitbiukd Photoob.4PH Co., Luhted. — This private 
company waa registered on January 5 with a capital of £25.000. in 
£10 shares, to acquire from Louis CraUree and R. F. Oriblxin the 
benefit of a secret process for the production of vitrified photographs, 
to acquire the benefit of an 0|)tion to purchase certain freehold pre- 
mise* at Eaat Sheen, known aa the " Derby Lodge Estate," to work 
the said process with a view to the production of vitrified or ceramic 
photographs on china, glass, opal, and similar vitreous Kiibstances. 
etc.. to manufacture and deal in ceramic coburs used in the manu- 
facture of tissue? and the Uke. etc. The subscribers (each with one 
share) are :— L. Crabtree, Holmhurst, Temple Sheen, .<.W., traveller ; 
H. F. Uribbon, 4, Deanhill Boad. JUst Sheen, S.W.. wine and spirit 
•iienlLiiit Tlie lir«t directors are L. Crabtree and R. K. (;ribbvii 
iIkjiIi permanent). Solicitors. Coupland and Ward, 1, Palewell Villas, 
Upper Richmond Road, East .Sheen. S.W. 



news ana Rous* 



PHcrroomAPHic R»cokd of Xottixohjui.— With the object cf 
<>btainin;; a photogr.) hie survey. n» near »a practicable, for the Not- 
tingham Public Librariee. .Mr. Walter Briscoe, the librarian, is 
asking (or gifU of ph. tojpraphs of utreeU, buildincs. and objecis of 
interest in the city. Many people have photographs .if liiU of oUI 
Nottingham and of present-day Noitn-ham whi<h will ~.me day l>o 
••bygone Nottingham." This ciUe- 1 ..n. from the l<«al lo|M.sraphii il 
standpoint, will in due course i* of errat value as well as interest, 
and will form an imporUnt addition to the lo«al culection in the 
fenlral Reference Library. 

Any of our readers •'lio are al le to reapoDd to thia request are 
,I«^ially aaked to writ* the desrription of the |)h..lograph and the 
\t^T of UkinK, on the back of the picture, so that these may lie 
pn.perly classified and kept in chron..l..sical order. Civers of pholo- 
-.{taphs arr aaked to encloae their nanien .mj addre.»e». so that ti.e r 
■ii(U ipay be acknowledged with thank* 

STBimso GeLATiXE PukTM.— A corr.-«p<j«ident . L Van Uvk. of 
the •' Inland Printer." contribtHee to the " PpK-e»» Engraving " 
department of that journal the foll/m-ing notes .« stripping and 
iranaferring ftkns from geUtine negatives, however old :— 

" Varnished negaUvee were soaked in denatured alcohol or 
nie«hv;a(«d spirit until it d ssolvr<l away. 1 do not use hydro- 
flw»riV acid now. aa I found fluoride of sodium to be so much 
«*ea|»r. and it doe* not go for the surface of the glasa or your 
fingers aa the hydrollooric doee. I flow all dry phUea first with the 
photo engravers' stripping coHodion and Irt it dry. Then I cut 
with a sharp knife point through Die (ilra all an>und and iwar the 

• dee of the g'asa. I next pour enifogh formaldehyde solution 
(..(nal ;ne) in a ruW)er trmy to ever the negative and dis»>lve in 

't ten grains of fluoride of sodiimi for every oonce of formaline I 
use. Ttie dry-plaU negative is then put to aoak in this formaline 

• Muti.^i for a few mimUea. or nirtil the oorners of the negative lift 
-a»ily with a penknife. Squeegee on the negative a sheet of paraffin 
|Mij»-r that has been laid in the solution over the negative for a 
-b<.rA lime. Then with the point of the penknife I loosen the film 

ir.f i!!v as I turn back the paraffin |«per to which the film is 
,11.1 ■.<l. WH arHJfther sheei of the (uraffin paper and lay the 
•inpiMi Aim down on that ao an to make a aandwioh with the 
film in the centre. Strip off the firM aliee* of paper and then lay 
the 6lin down on a clean sheet of albumemiaed glasa. Mrip off the 
Moood parafKn paper after sqaeegeeing the film very carefully to 
lb* Daw giMM aapport. rinse off with alcohol, and the job is done." 



Half-Watt .Stcdio Lamps. — Our French contemporaty the 
" Photo-Revue." in repi-iiiting the recent article by " Practicus " 
• m the installation of hiilf-watt l.inips for studio portraiture, adds a 
brief description of the system employed by an Italian photo- 
grapher, Signor Rossi, the results uf which, so it is stated, are in 
every way equal in quality to those made under the best condi- 
tions of daylight. It will be seen that M. Rossi's plan is aotually 
a studio within a studio, and is thus particularly applicable to 
studio* of e.\ceptionally large size, in which the reflecting action of 
the walls, in the way of providing a consider- 
able volume of diffused light, is very much 
smaller than it is in studios of lesser dimen- 
sions. M. Rossi constructs a wooden erection 
covered with muslin of the foi-m shown in the 
sketch. Its dimensions are about 13 ft. in 
height. 10 ft. in depth, and 3 ft. in width. 
The studio in which this erection is placed is 
Some 16 ft. in height, 15 ft. in width, .ind 
22 ft. in length. Three lialf-watt lamps, each 
of 1,000 c.p., are placed on one side of it, and 
are designed to form the principal source of 
diffused light. A fourth, of 3,000 c.p.. is 
dispoaed on the other side, and provides the princii>al illuminatinn 
of the aitter. Each lamp is controJled by a switch so that tlie 
lighting may be regulated at will, and the erection itseJf is pro- 
vided with blinds for tJie further control of the illumination. It 
ia itated that exposures with an //4.5 anastigmat and an e.xtra 
rapid plate are of the order of 1 second. 




Ansioers to Corresponaetits* 

— • 

SPECIAL NCPIGB. 
/a tenttfuiue of gtntral rtduetd $upplie» of paptr, OS tk4 rumD 
of frohiHtion of lAt importoHoH of ameA taood pmlp and grau, 
m om a tt w tpae* «mU W acotfoU* «a«f fnrthtr notitt for rapiief 
to sorr ssp imdsai*. 

Morwver, it i0iU antietr ty pott if $lamped and addruted saos- 

U>pi it tnrlottd for rtplf i S-eeni Inttmational Ooupon, from 

roadort airood . 
Tkt fuU pitttiont and annoert will 6* printtd onlf in tht latt of 

swywrJM of foneral intertH. 
Quoritt to ht antwtrtd in tht Fridaf't " Journal " mutt riaek a* 

nM later than Tu udaf {potttd Mondof), and ihonld ht 

addrttttd to tht Sditort. 



Photoobaphf.r, Southampton'.— For R.N.A.S. apply Office Com- 
manding, Photo-Section. 45. Victoria Road, Chingford. For 
R.F.C, Officer Commanding. Photo-.Section, R.F.C, Farnborough, 
Hants. 

B. H.— Dampness of the paper ia quite enough to account for the 
IllHff degree of brilliancy ; in fact, for a good deal more than 
thar fd^wn by the flatter specimen. At the same time, we think 
St il quite likely that differences in the emulsion night easily be 
the cause. 

W. R.— There is no reason why you should not supply joUv customer 
with a copy, that is to say," such an ordinary copy as you would 
make in the ordinary course. It would be a different matter if 
you attempted so to rojjy the form as to make the copy of such a 
character that it could be jialmed off as an actual exemption form. 

T. E.— Wo do not know what you should do, but you can certainly 
repudiate tho contention of tilie builder as utterly ridiculoiis th.-it 
tho "chemical stufi "' which comes from photographers' sinks is 
anything which by its nature cause* a stoppage in drains. If 



36 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



IJanuaiy 18, 1918. 



it is alleged tlhat such stopfiage has been oa<ii£ed by miittei- from 
your prumises, wc should say it is the business of the baiilder who 
makes such a positve statement to prove, by producing tihe 
inateriikl of Uie t»l>stni«tion, tliat it has come from your place. 

M. B. — It is dilliwilt to see how the projection lens can beoonr.e 
dewed by the heat of the lamp oliaimber. But obviously the 
remedy is to keep the projection lens well ventikited. Judging 
by your sketch your plaai «X)uld be to Iiave the bellows fixed to 
a separate support a little Wiind the lens frooit so that there is 
a clear air space all round the lenis. If necessary, a fm'tlher 
casing an inch or two away all ix>und may be put in position to 
cut off any light, but at the same time to allow ample circulation 
of air. 

A. E. B. — Under present copyright law, that of the Act of 1911, it is 
not necessary to do anything at all i« order to obtain copyright in 
photographs. The very fact of taking the photograph creates the 
copyright in it. In the ordinary course where an amateur photo- 
grapher takes such a photograph for his own purposes, i.e., " on 
his own," the copyright belongs to him. Where a photograph is 
taken to the order of anyone else who is liable for payment for 
the photographic work, then the copyright is the property of the 
person giving the order. 

Artificial Laght. — I propose using a Marion Northlight lamp for 
portraiture. Mostly for small groups and single figures. How 
many pair of carbons would you recommend? I am using a 3D 
Dallmeyer lens at the full aperture of F. 6. I presume this would 
not be quick enough for electric work. Would you prefer an 
anastigmat such as the Ross Xpres F. 4.5, or a Dallmeyer 3B, or 
similar lens of the same aperture? — Electric. 

The four-pair Northlight lamp is the most economical, as each 
of the two pairs is connected in series, thus utilising nearly all 
the current consumed. With such a lamp your exposures would 
not be more than in fair daylight, but if you have many children's 
pictures to make you would find it advantageous to procure one of 
the more rapid lenses you mention. 

H. J. L. — As you do not tell us what is the aperture of the projec- 
tion lens on the lantern — which is the chief thing determining 
exposure — it is possible for us only to guess at the cause of the long 
exposure. It is altogether too long: if the negative is of decently 
quick-printing quality, exposure on bromide paper should be only 
5 or 10 seconds. We should say the great length is due either 
to a poor incandescent burner or a lens of small aperture or unsuit- 
able focal length. Under your conditions the lens should be of 
8 or 9 inches focal length, and at least of f jb aperture. The 
incan-lescent burner may be. one of the cheap upright patterns. 
For enlarging there is no better gaslight than the " Howellite " 
inverted burner, obtainable from Messrs. Griffin, Kingsway, giving 
an exceedingly strong and concentrated light. 

EVLABGINO Lens. — ^Will yon please state if an anastigmat lens should 
give a sharp image at full aperture on the enlarging easel? I have 
an Aldis i-pl. 5|-in. F. 4.5, also a Cooke 8-in. F. 4.5 Series III. 
Both require stopping down to obtain even definition on the en- 
larging easel — the Aldis more so than the Cooke, although both 
lenses give a flat field at full aperture when used in the camera. — 
Frederick Smith. 

You do not say what size negative you are enlarging from, but 
either lens should give a good result with a quarter-plate negative 
if all conditions are favourable. The definition is affected to some 
extent by the illumination, and possibly this is not in perfect 
adjustment; while, also, the scale of enlargement may affect the 
flatness of field. Ordinary lenses, not specially designed for en- 
larging, are corrected for conditions which are only fulfilled when 

_ enlarging on a considerable scale, and when used for copying full- 
size or for enlarging on a scale of, say, two or three times, may 
not give such good results. 

MoNOMiET Drveloper.— Can you, please, give me any advice to pre- 
vent Monomet hydroquinone developer becoming stained? I have 
made up two lots exactly to quantities given in the "B.J." of 
August 24, p. 442 (Henry Hohnan's formula), but dissolving as 
suggested by A. W. H., of the same issue. It works well, but the 



last half-pint has on each occasion gone muddy before I hav» 
wanted to use it (about six weeks). I may say I use water that 
has boiled thoroughly for the whole solution. Would extra sul- 
phite, or, say, boiling the whole solution after making improve ito- 
preservative qualities? — A. T. C. 

If the water has been boiled briskly for five minutes shortly 
before using it for dissolving the chemicals, there wiU be •any 
benefit in further boiling the mixt-.irc- after chemicals have been 
dissolved. You might try the result of using rather more sulphite, 
say, 1 or 1^ ounces ; but we think the best plan would be to bottle 
off the solution when made into a sufficient number of pint bottles 
to hold the lot, filling each to the cork. We should say if yon do- 
this that you would be able to use the whole bulk of stock solution 
which you make at a time. 

F. S. H. — So far as we know, there is no useful method of lecovering 
developers or used developing solutions, nor from hypo baths. We 
do not think for a moment that it is possible to recover anything 
from used developers at a cost which would make it worth while. 
Hydroquinone has been recovered from spent hydroquinone de- 
veloper by bubbUng a current of sulphur dioxide gas through the 
boiling solution of the spent developer. A Mr. Lizius gave a 
demonstration of this process at the Royal Photographic Society 
on February 22 last yeav, but his process was not generally accepted 
in respect to any claims to economy. And on economic grounds- 
there is. no opportunity for recovering hypo from spent fixing 
baths. Obviously, 'when yc u use the hypo a.s completely as possiuJe 
for the conversion of the silver hromide into a soluble form there- 
is no great excess of unaltered hypo left in the bath. At any rate, 
we know of no chemical method by which such unaltered hypo- 
could be again obtained in a form in which it may be used for 
fixing. Our own opinion is that the chief form of economy you can 
practise is to organise fixing baths so that those which have been 
used for prints can be subsequently used for plates, when it can 
be seen (owing to the glass support) when they are approaching a 
degree of exhaustion. Of course, you can recover silver from the- 
baths, and that is the chief direction in which you can reclaim 
material from the solutions use-d in photographic work. 



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The Oldest Photographic Journal in the World. 
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IMPORTANT NOTICE TO READERS.— Vntil further notice 
agents will supply the " B. J." to order only, as " returns " are no 
longer accepted by the puhlisliers. This step has become necessary 
owing to the further restrictions imposed by tlie Government on the 
importation of paper and paper-making materials and of the con- 
sequent shortage of supplies. It is therefore necessary in order to 
ensure the regular delivery of tlie "B.J." each week to place an 
order definitely with a dealer, newsagent or book-stall clerk, or to 
send a subscription to the publisJiers. 



THE BRITISH 



JOURNAL OF PHOTOGRAPIT. 



No. 3012. Vol. LXV. 



FRIDAY, JANUARY 25, 1918. 



Pbice Twopence. 



Contents* 



Bi C*TaBim< 

Coriuaarr la Barnoi Pboto- 

aauas ta raa Uiitsd Statu : 

un ta tiimcta PvorooaAm 

la UaiiT BuTAiB 

CeriBno Povsa or Lcaasi Aas 

t)Ta*T Liaar la thk UAnaaA. 

B; Gcmlum M. Nicol 

OfLtamw Patanaa raoii Ama- 

TKoaa' MavATtTB*. Bj D. 

Chuia* 

AaiinAara' Nam 

AaALaeiA 



Tomrmoamam Bxaiainoai 

P*TB»T ■■«• 

Niw Boou 



38 

41 

42 
44 
44 



44 

. 45 
. 45 

. 46 



CoavaacuL abd Lcoal laTai.- 

uoiaca 46 

CoaaaBoaDaiia .— 
Kojal Ra*al Atr BcrrtM: 
Pbolecnptaic 8*etlon— While 
Uaakgnaadi in Hketch Por- 

tnila— lliuad BatloeM 47 

47 



Tkt S ti m mar p of eamlmUa which tmuUf oteufit$ tht hwtr half 
of thii eolumti vUl bt found at th* foot of tht pag* ovtrUaf and 
wM MbUwuM to U flaeed Ihtr* tchiUt \U rtyular potition it nquired 
for noMcw r4ktUmg to tht fortheoming " B.J. Alminac." 



to Oat tiM 

At Um time of writing — <two weeks before the Almanac 
•hould be on sale — the orders already received by our 
publishers total more than 15,000 oopiea printed. In 
other wvrds, the publishers are unable to accept further 
orders. 

It waa to be feared that the rapply of the 1918 
Almanac would not equal the demand for it even at tiie 
increased pricea of Is. 6d. and 2s. 6d. Even with the 
drcumstancce of both amateur and profeaaional photo- 
^nafthen so exceptional as they are at the present time, 
and even after allowance for the nnnbers of its customary 
raadera who are for the titne intent on other thinga than 
photography, it was antacipkted that the edition of 15,000 
would not satisfy all comers. 

So it baa proved, and therefore with our first announce- 
meoi of the fact should come an intimetion to those 
who have not ret ensured delivery to them of «n 
Almanac, and still wish to do so, that they must not 
look to the pubUahers if unable to purchase locally. 

As aoon as we possibly can we will announce the day 
of publication of the Almanac, which day. within the 
linntations of preeent railway transport facilities, we 
ahall endeavour to make the same throughout the United 
Kingdom. The reader should thus learn when he may 
expect to buy from his loovl dealer or bookseller, but 
unien he has previously ordered a copy to be reserved it 
n very doubtful if he can now expect to secure one. 
Distributors this year were at fint inclined to order on 
a Yny greatly reduced wnle : only when they had 
eridenoe of the widespread individual demand were their 
orders augmented to figures which have led to a total in 
exoese of the edition. 



EX CATHEDRA. 



Economy 
and Waste. 



Times like the present bring matters of 
economy and waste into great promi- 
nence, and many things occur that serve to remind ns 
that few .people realise the diflference. The facts tha.t 
economy may be wasbeful and .waste may be economical 
eeem to be unknown to many people. For example, 
eome eeem' to think that throwing a used developer or an 
exhausted fixing bath down the sink is neceeearily waste. 
A developer, or at least some developers, may it is true 
be restored to n-orking conditions, but it is not neces- 
aarily economical to attempt the task, even in these time;. 
It cannot be done without expense, and the final profit 
minus this expense may be considerably less than the 
value of the photographic work which might have been 
done in the same time. This will certainly be so in the 
case of a developer, and often will be so in the case of a 
fixer, for though it is easy enough to recover the silver 
from the tatter it will not be worth while unless there 
is a lot of it, for it will take nearly as much time and 
trouble to treat a gallon of fixer as it will to deal with a 
hogshead full. The man who is only a 'vary small user of 
hypo will gain nothing by attempting to recover the 
silver, though one using large quantities may gain a igood 
deal. The attempt, however, to recover the hypo, which 
has been suggested, is one that will pay neither the small 
man nor the big one, for it is much on a /par with the 
effort to restore a used developer. The photographer's 
business ie to make a profit out of photography, not out 
of chemistry, and some of the suggested r6.<rt!orative pro- 
cesses could hardly be made profitable at all, even by a 
skilled chemist working on a big scale. It is not wiaete 
to throw away a used and useless thing while it is waste 
to save rubbish, or, as some people say, " eoono- 
miee it." It may even be wasteful to economise on a 
useful thing. Hypo ie aiow short, but if a hypo bath is 
thrown away when it should be it will still contain a lot 
of unexhausted material. It may seem ectonomical to 
use it as long as it will work, but in that case j)rint'« 
nmr— ffrr and the saving of the useful hypo may be more 
tha a ' mi artced by a waste of priiitfi, and loss of repute 
and custom. 



Cleaning-up 
Print*. 



It frequently happens that photo- 
graphers receive prints for copying or 
framing which are in a more or less dirty condition, and 
require some treatment to remove, at all events, a portion 
of the surface dirt. Some caution is necessary in setting 
about this vinork, for what would improve one kind lof 
print would ruin another. Platinotypes are most difficult to 
deal with unices they can be unmounted and put through 
an acid bath, but much can be done by dabbing with 



38 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[Jmuaiy 25, 1918. 



a little stiff dough made tby kneading iwheaten flour with 
water until it is of an elastic consistency and does not 
stick to the fingers. Failing this, fine dry .breadcrumhs 
^vill pick up a great deal of the dirt, but care must be 
taken not to rub too bard, or somei of the platinum may 
be removed from the more delicate half-tones of the 
image. Rubber or eraser should not be used, nor should 
the surface be wetted. Carbons are easily cleaned; as a 
rule a pad Oif cotton wool damped with benzole or motor 
spirit will remove all surface dirt, but will not move 
any- working-up. The^eame method answers well with 
bromide or P.O. P., but with these soft rubber may be 
used, or even fine pumice powder applied with the finger 
tip and gently rubbed in a circular direction. A rub ol 
encaustic paste or white wax dissolved in turpentine will 
often do wonders in removing the tarry deposit from 
London smoke. Old .albumen prints, of which the surface 
is usually cracked, are difficult to clean, as any liquid 
tends to wash the dirt into the cracks and make matters 
worse. The dough treatment is tlie best for these, as it 
lifts the dirt from the cracks as well as the surface. 
Prints finished in water-colour may be dusted only with a 
soft handkerchief, and rubbed with nearly dry crumjbs. 
If there is any sign of the colour shifting, further rub- 
bing is dangerous. White margins may be cleaned with 
soft rubber; the green variety is the best for this puitpose. 
* * » 

The Fannily There have been many attempts to 

Album. revive the portrait album, but we do 

not believe that individual photographers have done as 
much as they might have done in this direction. The old 
decorated volume is without question as dead as Queen 
Anne, but there is still an excellent opportunity tO' intro- 
duce a more up-to-date article if photographers, and their 
receptionists, would take a little interest in pushing it. 
Tlie family ties in these days of stress are stronger than 
they have been for many years, and many of the photo- 
grapher's customers would gladly purchase any convenient 
appliance for preserving the portiiaits of those who have 
given their lives to their country, together with ,those who 
are still carrying on. The idea should appeal to the 
photographer, because every time an album is inspected 
it suggests bo someone the desirability of visiting a studio, 
or of acquiring such collections ot his own family or 
friends. The modern methods of mounting iit in well 
with the album idea. There are now on the market 
many good ipatteme of loose-leaf album in artistic shades 
of card, and it is a simple matter to dry-mount .with or 
.jwithout border tint® any specially made prints. Existing 
prints can have the mounts attached to the leaves by a 
f«w touches of seocotine. Damaged, or faded prints may 



SUxMMARY. 

In a leading article we deal with the reciprocal relations which, 
by official consent on both sides, exist . between tliis country and 
the United States^ in regard to copyright. The essential basis of 
the arrangement is that British pjiotographs in America secure 
copyright protection of a kind and -under the conditions which 
apply in that country, whilst the convei-se holds good here in refer- 
ence to photographs made in the Ujiited States by American citizens. 
It follows from this that in order for British photographers to 
obtain copyright protection for their work in the United States 
it is necessary to comply witli the American formalities in the way 
of registration and deposit of copies at Washington, and, in the 
case of photographs which are "published/' marking them 
"copyright." (P. 39.) 

Mr. D. Charles contributes some notes on gaslight printing from 
amateurs' negatives, in which he describes methods and home-made 
appliances which can be used for expeditious work upon a scale 
which may not justify the equipment which is used by large trade 
firms. (P. 42.) 

In a contributes! article Mr. iGraham M. Nicol has something to 
say on behalf of the older type of (R.R.) lens in comparison with 



be ciopied and worked tup so as to be uniform in appear- 
ance .with later work. We are sure that in any business 
with a "family" connection a sample album got 
up on these lines would be a good order-bringer. A 
great point about the album Is that gaps in the collection 
are always in evidence, and the defaulters get a gentle 
reminder that they 'haven't had their portrait taken yet. 

« « * 

The Need The advertising expert of to-day calls 

for a Slogan. any catch phrase used by a business 
concern a "slogan," a Gaelic word meaning a war-cry. 
Such .phrases as " Worth a guinea a box," and that one 
known to all photographers, " You press the button, we 
do the rest," are excellent examples, and have helped to 
fix the name or goods of their originators in the memory 
of millions. Every photographer needs a slogan, indi- 
cative of what he considers best in his work or methods, 
and which he will strain every nerve to work up to. 
" Portraits wh©n Promised " makes a good slogan, and 
will help to decide the venue of an order when prompt- 
ness is a desideratum. " Permanent Pictures Our Pride " 
is another gccd selling phrase, and there are scores of 
others iwhich are best framed .by the user, who is the best 
judge of ,what will best suit his business. It must never 
be forgotten that the slogan is not only a challenge but 
a pledge. It must be backed up by performance, and it 
must, when connected with photography, be uttered in a 
cultured tone. Mere self-^laudation is useless. " Gum- 
midge's Portraits are the Best " is worthless as a slogan, 
for it is a mere ex parte claim, with no explanation a^ to 
why they are superior to any others. The public has had 
enough of that kind of talk, and takes it at its true 

value. 

* * * 

The Sink A correspondent recently mentioned 

Waste. the contention of a builder that he had 

blocked the drains with "chemical stuff." It is difficult 
to block any reasonable " dram '> with the material put 
down a photographer's sink, but it is extremely easy to 
block the waste pipe leading from the sink to the drain, 
and we have known several instances in which careless- 
ness has led to such a result. People .^9® .apt to think 
that almost anything is capable of passing down a sink 
pipe, and, instead .o? -using >he waste .qiily for liquids, 
permit such things as._cofton wool,, gelatine, corks, etc., 
to fall into the sink-.and exwecft them to get out again 
somehow. Cotton a\^1 -is^«d largely in some dark- 
rooms, and old pledgets a^i^^opped quite as a matter of 
.course into the sink.___ Thsy 'may or may not block the 
,pipe, but if they dp/^e^; ^je capable of giving a lot of 
vtrouble. Washed offr.3^§er .labels and old corks will at 



the modern anastigmat. ..The lesser coveuing power of the R.R. 
lens and the consequent lesser amomit of stray light in the camera 
are the n-rounds on which he recommends the greater utilisation 
of the many second-hand, lenses of the R.R. type which are 
available. (P. 41.) 

Although tiie old-fashion«(d portrait albtm is thoroughly and 
deservedly obsolete, there still seems to be an occasion for pro- 
viding some form of album whicli, in accordance with present- 
day tastes, might be used for the assemblage of family portraits. 
(P. 38.) , „ 

In reference to the making of negatives (for sketch portraitsl 
with deiise deposit for the background, a correspondent pomts out 
reflection within the lens rfrom the ivJjtVe vignetting card m front 
as a cause of negatives which print grgy, in' the, ground. (P. 47. 1 

Methods which can be- used far, the. rflnovati6n of prints in the 
v,av of removal of mechanical d^' are^tjicsjibjeot of a paragraph 
on "p. 37. ■ ■ ■ ;, .... 

Cleaning arc-lamp glasses.. A'rgnettes. 'in stnp-printmg, tank 
development, finding fl number,' iltuminatibh in enlarging, and the 
use of the Dallmeyer portrait 'lens are among the subjects briefly 
dealt with in replies to corre.^pondents. (P. 47:) 



Jinuw}' 25, 1918.] 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



39 



times form most effedtiv« phigs. More substantial mate- 
rial, such as p&per or cofton wool, oan be stopped by a 
gating at th« outlet, and eucb a grating should always 
<be provided. We know of one case in which a P^pe was 
•plugged by a boitle bmeh which was dropped accidentally 
into the aink, and vanished down the open waste before 
it could be reocued. This kind of thing can readily 
happen, -and a cuitAble grating is the only safeguard. 
ATiocner source ot trouble is Dot a stcfppage but a leax- 
age, caused by pouring away strong acidfs. None but 
verv <blute acid should ever be allowed down the sink. 



COPYRIGHT IN BRITISH PHOTOGRAPHS IN THE 
UNITED STATES: ANP IN AMERICAN 
PHOTOGRAPHS IN GREAT BRITAIN. 

The cloeer relations which in the future must inevitably 
exist, in a hundred ways, between this country and the 
United States make it of some importance that the facts 
concerning copyright of photographs in the respective 
count rie« should be mutually understood. It can readily 
be imagined that with the more active share taken in the 
war by the American Republic and from the presence in 
these islands and on the Continent of Europe of thou- 
Mnds of American ciUtens engaged in tJie prosecution of 
the common aims of the Allies, there will necessarily 
oome into existence large numbers of photographs wfadch 
have as great an interest for the American public as for 
oursj and, on the other hand, photographs produced in 
the United States will likewise paeseaa, many of them, 
an interest for people here on account of their connection 
with military and other operations in Europe. In these 
cdrcumstances it is only fair that the rights of photo- 
graphers in reepect to the reproduction of their photo- 
graphs should be observed in either country — those of 
American citizens here; those of British subjects in the 
United States. Such an obeervanoe obviously can only 
oome from an understanding of the technical conditions 
m» regards legal copyright protection which prevail in the 
reapeMive countries. It may, therefore, be of intereot to 
our readers, both here and in Amerkk, if we briefly out- 
line what these conditions are. 

Until the year 1900 the United States, in the matter of 
reciprocal agreement ae to copyright protection, held 
almost entirely aloof from the arrangements entered into 
by other great nations. Until this time the only basis 
for reriprocal oonoessioos of copyright was that provided 
by the Chace Act of I89I. Originally it applied only to 
books, and granted copyright to auUmrs who were neither 
ortixene of nor residents in the Unrted States provided 
that the books were printed from type set within the 
Bepoblic. By modifications of this A«t of 1897 and 1905 
ita scope was somewhat extended , but, in regard to photo- 
graphs, its provisions never aHained any degree of 
definitenesB. Then, in the yeer 1909, the United States 
Government *et its botise in order in respect to copyright 
law by drafting and passing an Act. of wide scope, 
embracing all descriptions of work, literary', musical, 
dramatic, artistic, and photographici In the present con- 
nect.ion it is Sect. 8 of this Act which is of interest, in 
that it defines the baab of mutual copyright protection 
between the United States and other countries. Divested 
of a few superfluous words. Sect. 8 of the U.S. 1909 
Copyright Act is as follows : — 

Til- author or proprictnr of any work made the nabject nf 
<-»{iyri|(ht bjr this Act ^kall h»vp cr-|)>Ti^t for auch work nntW 
Um ooodHicOi and for the lemM spm-ifiM in this Art : provided. 
hofrsvar, tbst tha eopjrright secuml by this Act thai] extend 



to the work of an author or proprietor -who U a citizen or 
subject of a (foreign State oa' nation, only : — 

(a) When an alien author or proprietor shall be domiciled 
within the United States at the time of the first publication of 
his work ; or 

(6) When the foreign State or nation of wihich such author or 
proprietor is a citizen or subject grants to citizens of the United 
States the benefit of copyright on substantially tlie same basis 
as to its own citizens, or copyright protection eubstantiaJly 
equal to the protection secured by such foreign author onder 
this Act or by treaty. 

Such reciprocal arrangement referred to in Sub-Seotion 
(6) of the above was entered into between Great Britain 
and the United States in July, 1909, by proclamation 
of the President. The proclamation declares that Great 
Britain " has permitted to citizens of the United States 
the benefit of copyright on substantially the same basis " 
as to its own subjects. 

In other words, if you, a British subject, are living in 
the United States at the time of the first publication ef 
your work (photograph) — ^which is a different thing, by 
the wav, from the time of its production or creation — you 
secure copyright according to the U.S. 1909 Act as 
though you were a citdzen of the United States. This 
provision will interest few photographers here for the 
twofold reason that few of them are concerned in rights 
in photographs published during their (the photo- 
graphers') residence in the United States, and equaJly 
few are concerned in copyright photographs which are 
" published " within the ordinary meaning of that word, 
that is to say placed on sale so that anyone can freely 
purchase them. It is the second provision (6) whi«h 
chieflv provides the basis for the mutual copyright con- 
ce«rions between this country and America. Taken in 
conjunction with the Presidential proclamation sub-setStioii 
(/.) amounts to this: We in this country have granted 
to citizens of the United States the benefit of copyright 
on terms such as we enjoy; the United States grants 
protection to us in America on terms such as they enjoy. 
At the time this relation was entered into copyright in 
photographs in this country was regulated by the now 
repealed Act of 1864, but so' far as our knowledge goes 
there is no ground for believing that ithe British-Ameri- 
can relation is disturbed by the revision of our copyright 
law in the Act of 1911. which in some respects, e.n., the 
comprehensivenees of its scope, is much more closely in 
correspondence with American legislation than were the 
previous Acts which in this country regulated copyright. 
Thus, as a first consequence of a study of the terms of 
this reciprocity arrangement, it is seen that subjects or 
citizens oi countries other than the United States obtain 
copyright for tlieir photographs in the American Republic 
in accordance with the conditions set forth in the 1909 
U.S. Copyright Act. Inasmuch as the oonditions provided 
by this Act differ radically in respect to some items from 
those which are now the law of the land in this countij, 
it is necessary that photographers here should recognise 
tt)Sj}ifrl*i<^^ '" order that they may comply with the 
iiLiswsn W*! nil lii in formalities. So far as our reading 
goes, we" understand that the basis »f reciprocal copyright 
between this country and America is different from that 
fixed by international agreement among coiintries sub- 
scribing to the Berne Copyright Union, according to 
which members of each country observe the formalities of 
their own country and obtain the privileges granted respec- 
tively in the other countries. The wording of the U.S. 
Act, however, if it is not precisely emphatic on the point, 
can be interpreted only in the sense that we here must 
comply with the formalities in the United States and 
obtain the benefits granted under the American Act- 
whilst American photographers, on the other hand. 



40 



THK HIUTI8H JOURNAL OF PHOTOGRAPHY. 



I.Janimry 26, 1918. 



obtain our b«ii«flt« here without the obHervance of any 
fvrninlitifM Hjiijjdy for the rcaitun that uhder the 191 1 
Act th«irn mi; ikA, iitiy. 

BtM/ to coi ow to the procedure whicli in noccKHiiry 

in Uio Uiiil>4Ml S(iil4m ill order legally to Hocuro and iiiain- 
t»in ooityright. Jii the fintt ]>laoe it in iiecemary to 
regidter all ])}iot.ogra]>lu« with the (Copyright OHicc at 
Waiiliijiuiton. Th« iiwM>t(«ttry forms for r(!gi«trat ion jiro 
obtttinaUe fivm the Ooj)yri^ht Office, WaHhington. That 
lor )ihotogru|)hN piibliNliud lor Hale ih J 1 ; that for ])iioto- 
graphn not rxiirmliK^od for Hale in 32. On thnne forniH 
the nann' and (iddrvmt «f the u]yp]iomii nnmt Ije stated, 
the nalioawilit^y rdtiKt.'nithip, not race) of thn author of 
the Work, lit In <d work, and, in the cane of all ■/iiili/inli.rd 
workw, tlu' ncliinl dutt' of ])nll)]i<!ation. The fee for the 
regintralToii cif i1m< j>liolo),'ra|)li .in fifty cents when no 
(«*rt.ifH'Ht<* <»f rcijfii^l rntion m di^Mii'pd. II ih alwo iieoeHnary 
to dejKwit one ('<)f»y of th<» jdioiograpli, whi<;h ninut, 1m! a 
real jjhot-ogiraph, not a ]))iot;o-nieK-hani<!al r«])rodM<'tiolii. 
Thi« (U-ipoMiHon of ion « (•o(i)y ajjplies to pliotograplm which 
at the time of regi(*t rat-ion hiuve not been publiHiiftd, y.^., 
j^*l>rodiiirMHl /iitvr cnlo or j)nWai(;ly di«inl)n'l<Hl. If, and 
when, a pliotograpli dtt .|iii'bliHhml a furlliei' fOpy of it 
nnjniirew to Im* " pi>onipt'ly " di>po«ited at Washington. 
'I'lie wor<l " promptly " Ii'hih Ix-en <le(ined an " withoui 
iinn'ec<t««ry (N-lny," Init it. i« <)fli<»ially Htalod that the 
d«»]KiHit lUM'd not l)e ituwle on the very day of pnblU'alioin. 
The pnhlioalion relVrri>d to in tluwe in«trn<'it ionn for the 
regial ration ' of <'opyriight clAiniH HigniifleH |])Nl>lical.ion 
HliinnltianeioUiily in the United Stat'ca and in the fotieign 
eountry, r.//., the Unittxl Kinj^'dom. Thiw ])iibli«ilimi 
detienninwi the jierio<l for wliiili <'opyrigiht in the V.H. 
'\imitt, \\r.., twenty-isight y(»HrH froni the date of first, pub- 
lination. 

•^ A further reRiilation of (li<' U.H. Act. is that workw for 
whi<'li i'(>pyl'i>,'lrt i'H (tiaiiiKMl re<inire to Ix- marked " copv- 
rlght " when puibliMlied. In the (^aHe of photogra])hw this 
marking; may K^omHiKt of the letier (.' en<^loned within a 
cirole, thue ^o^, aeroni]»anied hy the initials, monogram, 
mark, or HyniliM)! of the copyrighit proprietor. Tu such 
oanes tlie namo itwelf of the copyri/j;ht ])roprietor tiinut, 
appear t«n wnne acwuHible ))ortion of llu* jdioiograph oi- 
on the mount. Tiiewe two pi-ovisions, th.'it of ,i-<>j;iistraii(vii 
an<l of mnrkinir publishe^l c<iipiJl*s, c(iii(stit.\ite ihv two 
fornuilili(>« whicli (x)jno within the regtilations of the 
Alneriean Act. The first ie fiiiniliar to nuwt ]>li<rto- 
jrraphers, inasmuch a« it. was a fenture of the l<>giHlati'(Mt 
in thin coxnitry previo«t« to the 1011 Act ; the second ha« 
never .been oi>d<vi-<'<l in tluN country in reference to j)lMo- 
graphe. A« ^^egaly^!^ the privileges in Aniei-ic/i, photo- 
gra||ihK broadly rank with other artjj'tic, works, except 
,11ta.t they are ])lnced in a subordinate oln,ss conipare<l 



with works of art u regards the damages which are 
recoverable in the case of infringement by reproduction 
in a iiewepaper. Such dainageB shall not exceed two 
hundred dollars (£iO), nor be less than fifty dollars 
(£10). 

And now to our American friends. Under flic 
reciprocity arrangement they are more fortunately placed 
as regards jirotection of their works in this country than 
are their Uritish brethren as regaixlw protection of i/n.n- 
j)hotogra])h« in the Unite<l States. The difference arise 
from the broad basis of the ccji^yright legiwlatSon in this 
country, which is cmibodied in the Act of 1911. By this 
Act the jirevdouH formality of registration was swept 
away. The simple act of taking a photograph creates 
the legal right in it, and no formalities of any kind are 
iK'cewary as a j)reliminary to taking action against any- 
one who may have infringed a photographer's loojjy- 
right. As we inter])ret the recipro<;ity arrangement — and 
it is the intorj)reta'tion which is laid iij>on it by eminent 
writers in thiis country on the law of copyright — a iphoto- 
grajjh taken in America by a citizen of the United States 
which comes into this couiiti-y obtains just the same men 
sure of j)rote<"t ion as if it were made in Great Britain by 
a British .subject. We conceive that it is not necessary 
that an American citizen, in order to obtain rights im his 
work in Great Britain, should register his photographs at 
Wjmhiiigton, us ho requires to do in, order to ^ak« good 
his claim to cojiyright within the United States. Such 
an interpretation is the logical conclusion from the terms 
of the io«ri])ixjdty arrangements between the two couai- 
tries, whereby an American citizen secures for his work 
in this coimtiy exactly the .same rights which a British 
subject secuiros in exchange for rights to a Uritish subject 
in the United States such as an American citizen there 
obtains. The fact that those lights in America are eon- 
<iiti(:nal on fulfilling; certain fonnalities, while in this 
co'unti7 they are not, is a fortunate oircumistaiK* for 
American ])hotographei"s, the real commercial value of 
which they no doubt fully appreciate. There are many 
other minor issues connected with the law of photographic 
dopyrighl in this country which thuR bwome of as much 
interest to Ain<iricaii photognqdiers whose work may be 
repiH;duced here as they are to thot^e in the.se islands. It 
would be a re]K>tition of much that we have previoiisly 
written in these pages if we endeavoured .further to dwell 
upon them for the information of our American friends. 
We may ])erha))s be allowed to say that the whole story lies 
ready to their easy reading in the manual " PhotoKraphic 
Copyright," which v*re jmblished from this office a year 
or two ago, and which our ))ublishers can supply at a 
price inclusive of jiostage to America of one shilling and 
one jieniiy (twenty-six cents). 



IIammkiinmith llAMrsiiiHK iiovsi':. Tiha aiimutb exHilbitidit hiM i 

liwn nn-mi]{(<il fur April 18, luul the followiiiK mouth. ' The jadfre 
tliln joiir will lie v. J. MorMiiuir, K.U.'P.S. Tli« opi-ii cIuhh will 
liK divitlod inUi two «iH-ti<mii ; (1) piviiU, (2) »lj(U>K ^iiiil Innmpaiviifics. 
MwIiiIk mill riM'liliriitiw will be uwurdml, Kiiiiil Jul<> for iwcpliuii 
»)( workn, Miiix'li 10, KuU pii.rl ioulurn and iii-<m|)('(tiii<i>» may In' 
obt^iMoiI fi'oiii ciMici" of tbo jiiini BivrelnrioR ; H. '1'. (Jiilli'iiilur, 10, 
Acre laiiit., HHxloii, JS.W.2j W, T, W, f^piom. aOLdolilliawkKoiid, ^ 

W,t2. Til > 'o|)rriitiop' iif nil pirtorlnl 'pllotogriiplii'Cs is en.nirxllv 

, invited, 
>TlilJiltNAi. Ai'P«AI,».— At riymolitli - liuit week Sy.lncy Joseph 
H»rry,'4, Hlnh Street. Ci-editon, phutonruphw mid hiurdrower, wiin 
itiVoil tixeiil|itioii by the knial t.ril>iinnl, and tlie iiiilita.iy iippciilrd. 
Ul^iiviu MlirlliiK m.id plii)t<iur«pln>vii \vi>iv wniilisl in (lie .\niiy. 
"VIm <<liHirm.'in wiid the Irllnmul wmiUl liUi«,t<i Hie asKiiii-d lliat wlicii 
tiloy iient »• nnui into tUo Army to dd <lt>nni4e woiU UiaT woiU wan 
givfn him to dij, Jn <iuo oi«»> wlnjre tin; IcilmiKxl had wiit a niu^i 
intq thp Ariny I)r9«u»^<. ^nen. v>f Jiit i-Mlliiig- \vci'(« .wiuUvd it wan di»- | 



covered thut he w«» employed picking up paiier. O^ptrtin Stirling 
rcptied that the po^tinR officer bad definite' ilislnict ions on the 
subject. All he could «a.y was that the list was snpplied him every 
inoiith of the triwli'H in which men -were wanted in the Army. 

Sr.MMKli TiMK. — 111 the HouRO of Comnions last week -Sir Greorge 
ifaVe, in re;)ly to Mr. Gilbert (Newingtoli, W,. .Ii.),,8»id :— Tlie 
experience i>f the second. year of summer lime has coinfirmed tile 
ciineluiiionH huaed on the ftr«t y<>ai'8 woikluR of tilio scJienie. and T 
tliiiiU it wall be in «ccord«nce with Uic Ki-'Ueral wiah.thatv suiuiii. ' 
time should he continued. As regai-ds the period during which i( 
ohftU 1m> put in force, the hon. member will rccolU>cl that tin- 
<lU(>»tiou was iuvestisatcd after the first year liy a Dcpartmciil.i 
Comniiltec wliicli ix>commcnded the (x-riod fivm the second Snnd.i; 
in .\pril to the third .Sunday oi September. This recommcndatui 
was adopted by Uie liovernnielit Inst year.' No decision has vil 
fieeu takeii as regard.^ this year. And , I , can onlj- say that,»i 
»lHjf*fioil of periixl .will he carefully considered In^fore the order 
'.mftde^ 



Juiamtj 25, VaUB.] 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



41 



COVERING POWER OF LENSES AND STRAY LIGHT 

IN THE CAMERA. 



Maxt photogrmph'n whMi thev pirrehaM a lens hsv« 
sot the opportunity of tetting it« pertonnance upon a 
plate Tcnr much larger than that which it is listed to 
•corer, and so do not coma to a dear r««liaation of what 
it* propertiee are in reapeet to the qualities which commonly 
go by the name of "covering power" and ''illuminating 
ftrwr." Generally speaking, it is aasnmed that covering 
{lower of a lens is a property which ia to be desired to the 
fullest extent The object of these notes is to set forth the 
doctrine that, within certain limitii, tlM contrary is true, and 
that while we owe a great deal to the opticians for the progress 
they have made in providing lenses ol great covering power we 
have at tite same time largely blinded onnehrsa to the definite 
advanUges of leasee of the older type which exhibit this 
quality to a much lease r degree. 

It nay first be desir»hle to obtain a practicsl definition of 
what is meant by covering power as distinguished from illu- 
minating power. The former term relates to t]ie aisa of plate, 
or rather to the diameter uf field, which a lens of giran focal 
l«i(lh will cover with sharp liefinition to the margins when 
pointed apon a Bat subject. The si4>jeet requires to be flat, 
for if it ia one conaisting of objects at various ditianoes, a lens 
which poaseeees what is known as cnr^atare of field may 
chance to exhibit better performance in the way of covering 
power than another which actua" "<>nor. On the other 

hand, illuminating po-ver denot< of plate or diameter 

of ftold which, in the same eiRun»taaese, is filled with dafini- 
tioa of a kimd. The defbution may not be good, but nevwrthe- 
iasa the laoa will form soma kind of iaage on the plate right 
Oft to the odfae ol lh« disc which amrk the limit of illuni- 
anting power. 

Now, in the views which are commonly expiwsaed in taxt- 
(woka on photographic optics it woald saan that the more 
«ov«ring power a lens p ci ass s sii the better it neresaarily is. 
Thas, to qnota a pasaage in one inannni on the tubjact, " the 
largor the cirelo covered by a lens ol given focal langUi tba 
better, because the lens can l>e moved about on tha caman 
front without fear of ill-defined corners in the negative, and 
also because the lens can be used to cover a larger plate." 
Undoobtcdly this expraates a large laaMara ol truth, inasmuch 
as the conditiuns named in it correspond with tboae which pre- 
vail vai7 frequently in practical photography. Bat in an 
axtaaaive reading of text-books and catalogaea dealing with 
|>hotographic Irasee I have rarely fonnd any attention given 
to tW affecta which different lensea prodnce in theae matters 
ef eovariag iwwer and illuminating power. Wkilo it ia tme 
that Maple covering power has its advantagca when yon usq 
the PiHira with the lena raised ur lowered, or when yon seek 
U) cover a larger plate, it is perhapa not so clearly kept in 
Bind that when yon axe not using a lena under theee condi- 
tions the rese r ve ol covering ^wer is not then n^atived or 
annnlled, bat haa its eflaet m the way ol illuminating the 
tellovB of tho camera, thereby creating a eoance of stray light 
witkia tfca caaara which ia a csuaa of many romplainU of 
veil or fiataena in negatives. Thi« efleet, of coume. tak<<* place 
equally whether it comes from great covering power of the 
l*:isor frooi ite wide 'circle f 'umination." So far as con- 
«eraa the creation of stray ; mh the camera, it doesn't 

matlar whether the illnmin,*.. ., ■■i Uia hallows ia dne to the 
Margiaa of an nnsharp or a nborp raagi The •ffect i* just 
the saoie in pmdocivg a aecondarr ■onrea of light within the 
camera which, in tha nbaa w t e of means to cut it out. must 
Itave iu tfrct upr>n the plate. 
The onlemae k4 these conswleiaiiona is that for many ut the 



purposes which come in the category of ordinary photography 
a lens of covering power such that its field extends very little 
beyond the dimensions oj the plate will prove in practice to 
yield results which are thoroughly comparable with those by 
an ansstigmat costing a good deal more. This applies to such 
work as copying, photography of ordinary views, and in gene- 
ral to subjects where (1) there is no call to bring the lens out 
of centre with the plate, and (2) where it is not necessary to 
work at a very rapid aperture. The anastigmat, with its 
large working aperture and its ability at that aperture to 
cover a relatively large plate, has tended to render us lees 
appreciative of the results which can be obtained with the now 
despised R.R. type of lens in circiunstances where one or other 
of theae two conditions does not require to be fulfilled. It is 
true that the definition towards the margins of a plate yielded 
by an R.K. lens at its full aperture compares unfavourably 
with that of an anastigmat at Hm lull aperture But when both 
lenses are stopped down to a medium aperture, such as fllb 
or fl22, the difference in the performance of the bwo largely 
diaappeara, and in these circomatances the R.R., from its lesser 
degre« of Covering power and smaller circle of illumination, 
scores on the ground of yielding negatives of a degree of bril- 
liance and sparkle which often it is difficult to secure with an 
anastigmat of similar focal length. I have no doubt I am 
telling a tale which is familiar enough to those who have 
lived through the era in photographic lenses which includes 
the coming of those of the anastigmat type. Old hands who 
have had the occasion and opportunity to compare the actual 
performanca o< the newer lenses with those which previously 
were their arrustnox^i instruments, and under the conditions 
formerly ap{>lying to thune instruments, have discovered for 
themselves that the merit of the anastigmat — let there be no 
thought ol ditparaging it — lies in the direction of creating 
better performance under fresh conditions which they render 
possible, rather than in improving the quality of work such as 
one was accuatomed to turn out in the days when the R.R. 
was the universal lens and ite limitations were recognised. 

The moral of all this — and it is one which may not inappro- 
priately be drawn to the notice of photographers in these days, 
when it is difficult to purchase anastigmat lenses — is that the 
precise purpose for which a lens is to be used should be care- 
fully Considered. It is not advisable to jtunp to the conclusion 
tiiat an anastigmat, if it ran be got, is necessarily going to 
do any better work thin an K.H. of the same focal length. 
I'r»bably it would surprise many of those who imagine that 
the anastigmat is tho lens par excellence for copying to 
i>baerve in process studios the frequency with which an R.R. 
figures on the copying camera. Moreover, the choice of an 
anastigmat of large aperture is apt to be particularly elusive 
when one of cun«id<rable focal length, such as 10 inches and 
more, comes to lie purchased. Here another factor quite apart 
from that of covering .power comes into pluy, namely, <iepth 
-ofeitadBn .Vssuming broadly that the depth of focus which is 
commonly caller] for in negatives is conditioned by the actual 
diameter of the lens stop (not by the fl number), it will be 
Ae«n that in uning a long-focus lens it is generally necessary 
t« use a medium or even a small stop to secure sufficient depth 
of focus. Obviously, then, there can be no useful purpose 
wrved in buying an expensive lens which works at fl^.5, when, 
for 90 per cent, of the subjects which are photographed witli 
It, it requires t" be sUipi)ed down to fllb or //22 simply for 
the purpose oi obtaining sharp definition. This, again, is a 
point which I am sure is familiar to photographers who have 
had much experience in the use of long-focus lenses in general 



42 



THE BRITISH JOURNAL OF PHOTOGRAPffy. 



;Jana-.ry 25, 1913. 



outdoor photography. It is another of those instances which 
leads one to the general conclusion that in photographic opti- 
cal equijHnent, as in that ior other crafts such as woodwork or 
metal-working, it is a ibad practice to endeavour to make one 
tool serve several purposes. Most certainly that applies to 



lenses. WhUe the anastigmat with its lai^e apertui« and its 
great covering power has its specific usefulness, the older typ» 
of lesser speed and lower covering power equally is unexcelled, 
as regards all-round quality of work, for certain purposes. 

Gbaham M. Nicol. 



GASLIGHT PRINTING FROM AMATEURS* NEGATIVES 



There cannot he the slightest doubt that the kind (A pnint, 
most in demand among amateurs is a plucky gaslight print 
with a narrow white margin. However good the prints are 
they will always have a neater and far more attractive appear- 
ance with a masked edge. This naturally means a little more 
work on each order, although, of course, it pays to take this 
extra trouble in order to secure and retain the goodwill of 
one's customers. By arranging some little conveniences at the 
start it is possible to reduce this extra work to such an extent 
as very nearly to wipe it out of existence. 

The first sketch shows a suggestion^ I n^ade in response to 
a friend's request .a few years ago. He h^ a developing lamp, 




over his sink, and an' ordinary electric globe over a table close 
by with a switch for exposing.,' In these circumstances, which 
amounted simply lo ama'teui'' conditions of working, each print 
called for quite a; series of 6pei'a.tions, including opening and 
closing the packets of fresh and exposed paper. My suggestion 
consisted simply in a boit open back and front supported as 
sho^vn slightly Planting Vith a couple of metal-filament globes 
arranged as in Fig. 2, and a little ledge on the bottom edge to 
support a prihting-Iimme of whole-j^late size. A piece of 
ground-glass is necessary to -diffuse and even up the light, 
which should be- rather near to the negative to shorten expo- 
suivs. I have found that reducing exposures in this Way does 
not have the flattening effect on the print with gaslight paper 
that it has in bromide printing. If the box is larger than the 
printing-frame it is easy to fix a piece tfl strong cardboard with 
a suitable aperture on that side of the box. The other side 
of the box, the open front, that is to say, is covered with yellow 
fabric or paper. Quite a pale tint is safe for ordinaiy gaslight 
paper, and even for the more rapid portrait varieties, if these 
are handled carefully at a reasonable distance from the source 
of light. Hence, one can work in practically full light and 
judge the depth of prints to a nicety in developing without 
peering at them and straining one's eyes. 

The method of working is to have the paper (enough for the 
order in hand), lying face down in an empty plate-box, placed 
in the shadow of this box. The paper is filled in the printing- 
frame by the aid of the yellow light, and the frame is then 
slipped on the ledge for exposure, after which the exposed sheet 
is placed face down in another plafcMaox. The paper will be 



quite safe in this way, as no direct white light can reach it. 
It is better to have a small stock of " soft " gaslight paper, in- 
addition to the ordinary "contrasty" grade, in. order to cope-, 
with the denser negatives, but the great mAJority of snapshot 
work is of the thin, under-exposed quality that is best ren-. 
dered by a vigorous paper. A make should be chosen, how-; 
ever, tha.t allows of fair latitude in exposure, ai^d that will 
stand some little time — up to a minute or so if necessary — in, 
the developer without staining. The better makes allow of 




Fig. 2. , 

this with care in working*, 'ancP permit of slight variations' 
which enable one to deal with difficult negatives, and get im-- 
proved nesults. For this reason it is very false economy tc 
buy a cheap grade of paper if one's aim is to retain custom by 
producing good work. • 

One very useful point in this direction, but one which is' 
often overlooked, is the judicious use of the " pot. brom." 
bottle. Gaslight paper needs fairly fresh developer, 
preferably M.Q., and a normal exposme with a normal 
developer gives pure blacks. Now, too much exposure gives 
(with quick development) increased contrast, but at the same 
time tends to give greenish blacks. Too much bromide in the 
developer will also give green blacks. On the other hand,; 
short exposure with prolonged development, which is useful in 
dealing with a rather " contrasty" negative, but must not 
be carried out in any extreme manner, will give a somewhat 
softer print, but of a colour inclined to bluenblack. A deve- 
loper containing insufficient bromide will give a distinctly 
bluish-black print. All this may sound vei-j- discouraging to' 
one who has been used to bromide paper, and who realises 
that the requirements are prints of a level black colour, 
neither bluish nor greenisli. A careful worker can, however, 
use these apparent vagaries to his own advantage by a very 
simple plan. This is to make up the developer without any 
bromide, and to have the latter of a definite strength,' either 



JaniMry 25, 19ia] 



XaE BKinSH JOURNAL OF PHOTOGR.VPKY. 



43 



10 p«r cent or saturated eolurioii, in a dropping>1>ciUle. 
Another way is to nse a foantain-pen filler as a' dropper. For 
the arerage M.Q. developer it -will V found that one drop of 
10 i>eT cent, bromide in each ounce will give a pare black 
aaslight print with noimal eiposui>\ but the exact amount 
for any formula ia quite easy to discover by means of • few 
trial slips. When printing, one can [mt the noimal exposures 
in a box by themselvee, the prints that have been over-exposed 
(t'> increase contract) in another, and the ones with short 
exposorea in a third box. 

The developer is meaaared out, and about half the normal 
amount ol bromide added' and wrU tlirrtd. If the bromide is 
n"t evenly diatribated in the develoi>er the printa are sure to 
b«- less satisfactory, and ihere is nothing like gadight paper 
f r showing up little careleattieaiea like this. The fully-expoUd 
prints are first developed in this bath, and it will be found 
that the tradency to greeoiah blacks cauaed by overexposure 
will be tkaknced by the abortage ..f bromide which tends to 
blue. Having developed these, tJie n-mainder of the bromide 
is added, and the normal prijits i>at through, and then a ver>' 
few drops more bromide will counteract the bluish tendency of 
thv under-eoqKised abeeta. I say a few drops only for t<w» 
rcasoiM. One ia th«t this nnder-ex|>oaar« for softer result* 
I'xniiot be carried very far, and tb« other ia that by the time 
thriH> prinU are reached the dev«|o()«r will be already in a 
half-used condition, in which it tends of itarif to give a slightly 
fCrwniah tendency. For tiiia reason it is not wise to use deve- 
lojier to enhaustion ; alao used-up developer ia far more liable 
to stain. 

This brings roe-to ihe question of staining, for which gaslight 
l>a{>er has rather an nndaaerved repiulUon. To get stainrtl 
prinM is certainly sasisr than ^th mott other printinj; pn>- 
cesMS. but <.nce one gets the secret it is just as easy t»> avoiil 
staining alt"e.»»her. The first point is to renew both de\-eloper 
and the S' '■ith fairly olten. Both are quit.- g.-^l for 

plates whti . . used for gasJigM wofk. Th» aecoud.pinnt 
i» to keep the print as nurli a» p<wsibl» away f rtmi exposure 
to the air fn^in »'■•• >" -nient it is «ett<,<d by develifier until it 
has been in td r at least twenty or thirty s««oniIs. 

This mean* thai it i* uetter to u»e b '' i • " 
of * lair depth, s<> that prints can U- 

This need nut mean large qn - arc 

chosen of a suitable siae an<l . ■■\«t. 

I always prsfar a big batii witli piviii> of aolaUon. TbiaeaablM 
one to plunge each print right un<ler the solution by means 
of a print paddle, and by the same roaana to move it about 
for • few seerjnds. It is just those few aaconds in the h}-p<^ 
that make all the diflvrmre in preventing two definite kinds 
of »uin. The "prirf ' " " also avokls any trace of hypo 
^(••ttinK on one's A>- 'mgers. whkh is again fatal to 

!•■ •• - trrtainly it is advisable to rinse 

* »i'l fixing, preft-mbty running the print 

*■ iie stream of witer from a tap. Wlier*? 

-f water i» ne«-es-iry (and in war-time it i« 

•1 iv-il saving to ih«> r'jmmiinit_\ i nVimise in water), it is a 

go-i plan to draw the print to and t:- dtrough a Urge vniuine 
of water in a sink or a Mg dish. A- I have had only two or 

thnw cases of '-^ -— ng miny thousands of gaslight 

prints made Ju .-w yesr» simply \}\ following the 

•bore mMlHxis, I tiimk 1 can >ir. !^ ' laini to have killed the 
stain Uq^sy in gnoli^ht wrk Ti i« 'nit I have made a point 
whenever i -istant t" pre«iiie at the 

hrfx'-dish II.: a large batch, say, any- 

thing over Tits. This is a irreat time-saver, as it is 

po*<ible t<> :ate all one's time and mind, as well as 

both hands, on developing, simply flinging each print as deve- 
1'>I>^'1 int». the rinae-water. 

I pr- (...•p now to dsacribe the •[><< lal printing-frame 1 have 
used for this work. It is easy to -i I ipt an ordinary- frame as 



shown in the drawings, and if not quite ideal, it saves a lot 
of time, and makes masking less of a fiddling job. The frame 
is a whole-plate one. and mine hae a spring which works on a 
sort of hinge, and clips automatically on pressing down the 
loose end. The other spring is removed, hand-pressure being 
used for exposures. Fig 3 shows the side view of the section 
of the frame with the back open, and Fig. 4 is a plan of ihe, 
arrangement closed, the dotted line representing the opening 
of the mask. I should mention here that although a large 
variety of masks is required, the opening of each should have 
one side to come exactly in the same place in the frame, that is, 
just ol«ar of the ends of the two smril springs, the ends of 
which just project .under the edge of the hinged back as shown 
by the dotted portions. By gluing fairly thick material on the 
back-board these two points will not afiect good contact. 

The two springs referred to are bits of thin spring brass or 
other metal let into a narrow strip of wood and fixed by 
small screws as in Fig. 3. The long spring of tlie printing- 
frame has two holes bored through, so that the wooden strip 



r" 
I 




Fig. 3. 



can be screwed to it. I think the other portion of the back is 
sufficiently described by the sketch. 

The modus operandi is simply to 'Jay the mask — which is ^ 
the full size ol the frame, and has the aperture size and guide 
marks on it— either in white ink ur marked on bits of gimi- 
paper — on the glass in the frame. Then lay the film 
on <o/< of the mask, adjusting it according to the subject, and 
by then closing the one large spring the points of the t>vo 
smaller springs will grip the film just clear enough of the 
opening of the mask to allow a clean straight edge to be 
printed ^y 'the mask, but close enough at tlie same time for 
films which have been trimmed rather close, or of which it is 
nut desired to mask off any more of the subject than can be 
hvliied. It is possible then tu 'feed the paper without an}' fear 
of tho maik or film slipping. The film can be, slipped under 
the mask li desired, but I find that the opposite is easier and 
quicker in adjustment, anA gives a scarcely noticeable diffusion 

to til k->' of the white margin in the print, which I think is 

p, . I a very sharp edge, which is a]rt to catch the eye 

raii>ei OL,. aptly, especially in flat or fuzzy prints. In suc^ 
cases the excessive sharpness of the margin would be by. coii:' 
trast to the detriment of a print rather than enhancing it, as 
is the object in view. 

In the case of printing from glass plates the mask must 
nearly always be on the film side, unless cut rather small, and 
it IS desirable to employ as a carrier a slip of card with an 
aperture cut on it to take the negatives. It is very undesirable 
indeed to keep a large stock of various sizes of paper to suit 
the enormous number of sizes of amateur negatives. It is moro 
economical in the long run to have a fresh stock for the more 
im|>ortant sizes only, even if it does mean trimming rather 



44 



THE BRtTISH JOURNAL OF PHOTOGRAPHY 



[January 25, 1918. 



mnch off aftei-wards. It is pretty useless to try and print so 
as to require no trimming. There will be a lot of time wasted 
in "filling in," and the edge will never be clean like a 
-trimmed edge, nor even all round either. I used a Trimerette 
as the handiest thing I could find for getting just the dcsii-* d 
amount of margin all round every time. The lines on the cellu- 
loid enable tliis to be done, and it is easier to get it right than 
in a big trimming-desk. 

I think I have described my method of sorting the finished 
prints before, but perhaps it will bear repetition. It is to lay 
■out all the prints, irrespective of whos« they may be, in lines 
on a clear table or bench according roughly to size and to type 
of subject. For instance, one line for quarter-plate groups, 
another for sea-scapes, and so on. When that is done, all 
prints from one negative being in a pile, of course, the firsit 
set of negatives is taken one at a time, and from the size and 
type of subject the prints can be picked out in an instant aftei- 
very little practice. This plan makes for correct and clean 
handling oi orders, and takes far less time and energy in the 
long run than any other I have tried. In fact, I have never 
been able to find any other real meihod for this part of the 
w<xrk except marking the backs of prints with the order number, 
-which I found a terrible time-waster, as well as spoiling the 
clean appearance of the prints, and tending to stress marks. 

D. Chaki.es. 



jissistatits' notes* 

• — 

Notes by assigtants suitable for this cohimn will be coneiihred 
■ and paid for on the first of the month following publication. 

Care of Chemicals in BulK. 

When a keg of hypo or carbonate crystals is opened, it is not 
often that the end knocked out retains any resemblance to a 
lid; aa a rule, it is' ju&t three or four bits of wood, and even 
when it is removed carefully tlie circular piece is not by any 
■means an airtigiht dust-proof cover, or even, a handy one. 
. If chemicals are to keeip tJheir quality while in stock they need 
at least a little protection, and where sulphite, ca-rbonote, and 
hypo are kept in casks or barrels it is a good plan to saw the 
iboibtora thiii-d out of a few old ones. Wide barrels should be 
cihosen if possible, and those with wooden, hoops, wihich are fairly 
common at present. The thdrd, it sawn off to include the hoop, 
-makes an exceUent lid, and though not actually airtight, is suffi- 
ciently near to it, and will keep out all dirt and other foreign 
matter, .such as parte of the weighing tackle, whicli seem to liave 
■a penchant for i investigating open kegs. A lid so made should De 
.examined for nails and also old tmces of chemicals, and both 
-•ghould be canefuMy removed. When two or more casks are so 
"Kdded " it is advisable to nunuber them.; this wiU prevent the 
"liida becom,i!ng mis-sorted, and so presei-ve each ohemioal from 
«races of the others. 

A rope handle can l>e added if desired, but the lid should not be 
'bored, or it may defeat its own pui-j)ose. The rope can be tied 
«)and under the smaller hoops and a atraod tied across. 

If the cheap modern kind of keg is used, one of these lids can 
1)e made by aJmoet anyone in less than half an hour, and will last 
■for years; the weE-made iron^hooped barrels are sometimes hard 
-to out, and so wiith them it is a longer and a liarder job. — 
Tbkrmit. 

Good Prints from Bad Negatives. 

It is not every printer who enjoys a guaranteed run of perfect nega- 
-tives, not even among the class houses, and it sometimes occurs that 
■superior prints are required from inferior negatives. When using 
development papers one of many serviceable dodges is to use scraps 
of ground glass to balance up an irregular negative. The broken 
bits can be kept in a plate-box, and by arranging them on the hori- 
zontal diffusing screen in the printing-box it is possible to even up 
a harsh negative to any extent, and also to put a little contrast into 
a flat one. 



When printin'.; off multiple negatives pieces of matt glass (cut the 
exact size of a single negative) will save a lot of cutting, and, inci- 
dentally, 7>r'nting; ond the necessity for slicing sheets of prints in 
the dish (when the different negatives on a plate are of different 
densities and have been printed together) disappears. Better prints 
result from this method than by dodging the developing, for when 
the pieces of matt glass are arranged aright, every part of the 
print gets its correct exposure and develops normally. — Thebmit. 

An Easy Method of Writing Titles on Negatives. 

A QCITE efieotive method of doing this is to write with " Photo- 
pake " with a small bi-ush or pen, but as the writing must be done 
backwards and irom right to left, it requires a good deal of prac- 
tice and a lot of .skill, to make it neat and presentable. A much 
easier way is to place the negative in the retouching desk upside 
down, with the film side outside, and to put on the writing (com- 
mencing at the left and working to the right hand, as in ordinary 
writing, but putting on the letters upside down). It will be found 
in practice that many of the letters are the same each way, and 
the others no more Jiificult to make one way than the other. The 
whole process is very much quicker and simpler and the letters 
easier to form than when writing backwards. To simplify, the 
matter still more it is best to make a key alphabet. This can be 
done in a few minutes. Get a piece of glass — an old negative which 
has been cleaned will answer the purpose — and write on it in 
" Photopake " a set of letters ti-om A. to Z, and numerals from 
1 to 10, of the style you intend using. Block letters are advised as 
being very easy and elTective. These are written in the ordinary 
way on the glass. When it is quite dry the glass can be turned over 
and placed upside down near the work in hand. We shall then see 
at a glance the shape and formation of each letter we wish to use. 
With a very little practice we shall be able to do excellent work by 
this simple method. — E. Hinge. 



jinalectd* 



Extracts from our weehly and monthly contemporaries. 
The Angle Included hy a Lens. 

The angle included by a lens indicates the size of plate which will 
be covered by it (says a writer in " Photogra<phy and Focus" foi- 
.JanuajT- 23), and can be found by observation, provided the len-s 
can be put on a camera with a ground-glass screen larger than the 
field covered by the lens. The field is then seen to be of circular 
shape, and the size of the circle over which the definition is satis- 
factory can be noted. If the diameter of such a circle is marked out 
on a sheet of paper, and on the centre of that diameter a line is 
drawn perpendicular to the diameter, the length of such line being 
made equal to the focus of the lens, the other end of the line being 
joined to the e.-itremities of the diameter by two straight lines, the 
angle between these two limes will be the angle included by the 
lens. On the othei- hand, M we know the angile included aaid the 
focus, wo can find the size of plate whidi will be covered by ruling 
a line equal in length to the foous, drawing from one end of this 
line two other lines, each makinig with the first line an angle equal 
t.0 half that included by the lens, and producing these lines untaJ 
they cut a line drawn fi-om the othei- end of the first liiie and at 
right angles to it. Such a line will then be a diaimeter of the fieW 
covered by the lens, and a circle with tliat diameter can be 
described. Any plate of such a size that it will lie wholly within 
that circle w-e tlien know wiiU be covered by the lens. Put another 
way, the lens will cover any plate the diagonal of whidi is not 
greater than the diameter of the circular field covered by the lens. 



FORTHCOMING EXHIBITIONS. 

February 2 to 9. — South Glasgow Camera Club. Secretary, John 
Baird, 164, King's Park Road, Cathcart, Glasgow. 

February 9 to 16. — Glasgow and West of Scotland Amateur Photo- 
graphic Association. Secretary, G. S. McVeau, 125, West 
Regent Street. Glasgow. 

February 21 to 23. — Leicester and Leicestershire Photographic 
Society. Sec, H. C. Cross, 80, Harrow Road, Leicester. 



JanuaiT 2S, 1918] 



THE BRITISH JOURNAL OF PHOTOGR.\PHy. 



45 



Patent ReiDS. 



Proem patenti — apjtOcatimt and tpecifications — ar» trtaUd in 

.Vpplicatioiu, Decenilwr 3 to January 12. 
CoLOCK PsiimNa. — No. 18,138. Photographic metiiod of colour 

Mfwiatian for ookMir priDting. J. R. ElsworUt. 
Photookapht.— No. 18,141. Photoj^-raphy. J. T. Smith. 
COLOUBKO PBorroGRAPBs. — No. 18.648. .Mcihod of producing 

ooloorcd photograpbic viewB. K. Pederaen. 
CamBUS. — No. 18.918. BoU-fikn ismeru. H. Workmen. 
CaoMt*. — No. 522. Photographic camerai. IntematioDal Patent 

Lioenaiiig Corporation. 
CAioaua.— No. 19,299. Cuwrai. .M. Niell. 
CoLOcm CnicXATOORArHT. — No. 17,881. Polychrome etnemato- 

grspby. A. Hanaborger. 
CoLOVK PBOTOOkAniT. — No. 17,882. Colour photography. A. 

Hamborger. 
C'«Lor« PaoroGRtniT.— No. 17,8&S. Mnlti-coioDr photography ana 

rinematography. A Hamburger. 
■ Nox-rLAM Film.— Nn. 18.410. .Manofaetars of noD-inflainmable 

' itea for ciiMBatography. W. C. .Stevenaon. 
'MnavOamuAMKArar.— No. 19.302. Stcreownpic cinemato 

ftraphy. L. L. Ruffier. 
CnrucAKXHurHT.— No. 677. Cinematography. A. Garbartni and' 

L. Maoclairv. 



trade Rama and marks. 

MARKS PLACKO OS THIS HEiilSTEU. 
Tht foltumutu uuirkt kar* bttn plnrM on th» raguUr : — 
.Sijnuu. — No. 379,791. Chamical ptaparationa for pi«aer\'ing 
pfaotogra^k develnpinK lolutiona. George WiUiam dear 
SMratan, 210a, Tufnell Park Road, London, N.7; photographer. 



REGIS TBA TIOSS JlEyE WED. 

EsUGic— No. 260.822. Re,;UUr(d hj Hoogbtona, Ltd., in 19M 

(CtaM3). 

R.<taiOK.— No. 260.823. Regittered by Hougblona, Ltd., In 1904 

lC*laM 8). 

E^inoif.— No. 260,824. Regiitered hj Heagfatona, Ltd., in 1004 

<Claa« 15). 

TxsMK.—No. 2^,825 Regiatered 'qr Hoa|^laaa, Ltd., in 1904 

(Claaa 16). 



Rcu) Books* 



Tkc Wellcome Eapoturc Record and Diary, 1918. L.oadoD i 

BurroaAha WcUcomc and Co. It. 
"Wc arc glad to ftnd that paper ah»rUga haa failed to interfere with 
nhe p t m ^ m t ti im t of the ercr-popular axpoavre diary of Jieaars. 

Barrougha WaOeoma, which raachra oar table almost at ita. accua- 
•tit\iwA tima, with no nark of a wurld war upon it except th*t it 

in. ivrhapa, a little thinoar, b^ n<> mean* a .feature which can be 
■criticiaad in • votnae iaiaaded partiealarly for the pocket. We 

have 80 often, in rafarring to past iMncs of ! the diaiy, dwelt upon 
'!>!•' point of petfectioD to which it baa tiaen brought and the real 

• liflirtiltiM which moat confront the oompUert in introducing any 
uMur featasa, Ihnt olM minor improv^ncnt in iha preaeot -volume 

daMrraa to ba ■anliflwad namely, * little wallet of atill card 

altacbad to the inaide front eorer, within which tmall prtnta or 
■other papan can bo placed for m< urity. The test portion, which 

dral.4 with pn»inaia of pbotogra|>hy carried out with the tabloid 



chemical prefMfstiona of Ifeaan. liurroogfai Wellcome, has been the 

.iLibject of ffnwiJainble revision, so thai it occupies a leaser number 

"f rages, bat withoot any aacrificf of the explicit directions which 

omatear photographar appreciates.. TJiat most easential part of 

diary — the exposare calcniat'lr and the tables accompanying itx 



use — remain the same, except that the list of sensitive plates <ani 
films now includes only manufactures of the Allied countries, with 
the exclusion of any of enemy origin. We are quite sure that this 
feature alone will onc^ again recommend the volume to innumerable 
purchasers, who can obtain it in several editions — one for the 
Northern Hemisphere and for use in the Tropics, and two others. 
one for use in the Southern Hemisphere and another in corresf on- 
dence with conditions in the United States. 



The Sctentist's Reference Book and Durt. — The 1918 e.lition 
of this pocket diary, issued by Messrs. James Woolley and Co., 
Ltd., Manchester, price 2a. 6d., preserves the features which for 
twenty years past have rendered it valuable to those in scientific 
occupations. Within 150 or so pages is collected a mass of <lata 
specially in reference to meteorology, astronomy, agricultme, 
weights and measures, chemistry and chemical analysis, physics, 
physiologj-, and hygiene. The diary proper is modelled in con- 
venient fashion, and, unlike many other pocket diaries which we 
see, includes, we are glad to note, space for a Sunday in each week. 
In its stout leather covers the diary is one which will render its 
seni-icea to the possessor throughout a twelvemonth. 

Thb Pk.nrose Pi.(«fas Diart.— Tlie pocket book and diary 
issued by Messrs. .\. W. Penrose and Co., 109, Fairingdon Roeti, 
£.C.l, appeals for tlie year 1918 in its accustomed forii: and will 
•onca agaii^ be wekwmed by those in iBhe phcrto-engraving trade for 
it« oomprofaeiiaive collection of working details, formulae, , and tables 
ouimected with the various pboto-meohanical processes such as line 
and half-tea* engraving, three-colour work,' coIloty|)e and plioto- 
Ittbogrftpby, and photograivore. In addition it contains special 
notes oo Che preparation of originals, the wet-oollodioii ami 
collodion tunulaiod processes, atid includes besides such general photo- 
graphic fomnibe as developers, fixing baths, reduqars, sntensifiers, 
etc Its ulitor, .Mr. William Gantble. is ito be oongratulate<l on 
having maintained the continuity of this most useful pocket book. 

QrAKHTT PHOTtKiBAPHic Printinc— ThePB is now no occasion to 
withhold reference to the nunlberi of our little contemporary tlie 
" PbotO'Miniatore " until mippliei readi tfiis countr\-, for the reason 
that importation in bulk is now prohibited, and those desiring any 
iMrae of oor contemporary require to buy it direct from the 
publishers in New York. Messrs. Tennant and Ward, 103, Park 
.\ venae, at the price of 25 cents. The 'lateat asuo, No. 166, is one 
wltich will interest ]irufessiooal photographers lin tliis country and 
particularly the many who are en0ige<i in the productioii Of portrait 
and othor printe in Urge ({uantitie* at popidar prices. It describes 
methods of machine printing, vignetting and bordering, dievelop- 
meot, fixing and waaliing as the^ are practised in estaJblishments in 
the United States working upon tlie largest scale. Amon^ the items 
which seem to us to be novel is a triple tank for the hot-toning of 
priiita by hypo-alnm. Another is a rotary "buffer" for the pre- 
iiminar)' polishing of ferrotype or glass plates on which prints are 
to be squeegeed. We referred only last week to the many 
opportonitiea w4iioh still remain for the greater application of 
elcctrit |owrr to |iliotographic operations. The present issue of the 
" Photo- Miniature " is a reminder of certain directions in which the 
cleaidy power of an electric motor call be utilised. 



Pno»<Tl Flashlight .Ststem.-:— Since mentioning a month or two 
ago the very comprehensive catalogue of the lampe and powders 
im^a-tii the Prosch ^Manufacturing Company, 334, Fifth Avenue, 
^WlXork, we have received a new edition of the list, which is a 
(iUn'jnore' complete and detailed iipecification of the many requisites 
for flashlight photography of all kinds of which the company are the 
makers. These, for example, are the various forms of collapsible 
and fireproof flashbags designed for flashlight photography in 
studios, at banquets, and for at-home portraiture. The catalogue 
contains a ver>' great deal of practical instruction in the way of 
placing the flashlight illuroinant, ignition, etc., and we can imagine 
that no photograjiher anxious to inform himself of the full facilities 
which are at his disposal, or, at any rate, will be at his dispoKal 
when transport faciliUes . between here and America are again 
aocmal, will neglect the occasion of obtaining this price list, which 
is sent free on application" to bo'ua'-fide readers of the "B..J. " , 



46 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[January 25, 1918. 



meetlnss oT societies* 

» — 

MEETINGS OF SOCIETIES FOB NEXT WEEK. 

Satvbsay, January 26. 

Hud()ersfl«ld Naturaliat and Photographic Society. "The Nataral History of 

Uy«s and Dyestufts." L. Neaverson. 
Btalybridge Photographic and Scientitlc Society. " Enlarging." J. Kershaw. 

Monday, .January 28. 
Dewsbury Photographic Society. " Chat on ' Photonraina.' " W. E. Oundill. 
Bradford Photographic Society. '• How to Do It; SoioB- Methods and Manipula- 
tions ia Photography." J. F. Seaman. 

toEBDAT, January 29. 
Royal Photographic Society. "In the Alps with a Camera." Dr. C. Atkin 

Swan. 
Birmingham Photographic Society. " Tunis." Harold E. Jeffories. 
Hanley Photographic Society, Y.M.C.A. "Landscape Photography." J. Wright. 
Eeighley and District Photographic Association. " Wild Cumbria." J. W. 

Shnttleworth. 
StaWbridge Photographic and Scientific Society. Annual meeting. 
IMonkiaiuls PhotoKraphic Society. " After Treatment of the Negative." Practical 

Demonstration. A. D. Wilson. 
Hackney Photographic Society. "A Walk Round Wanstcad Park." A. E. 

Farrants. 

WEDNE.SDAT, JANUARY 30. 

Croydon Camera Club. Annual Genersl Meeting. , 

Bristol Photographic Clnb. "Garden Portraiture and Studio Portraiture." Mrs. 

F. Wild and Miss Brownlee. 
IKord Photographic Society. " Northern Italy," W, Sanderson, J. P. 

Thursday, January 31. 
Hull Photographic Society. Lecturettes on Excursions. 
Liverpool Amateur Photographic Association. " Some Investigations in Three- 

Colour Bromoil." 8. H. Williams. 
Hammersmith (Hampshire House) Photographic Society. "Bromoil." G. B. 
Clifton, F.R.P.S. 



ROYAL PHOTOGRAPHIC SOCIETY. 
Mketino held Tuesday, January 22, ifche President, Mr. Johai H. 
Gear, in the chair. 

Mr. R. H. Lawton read a paper on " The .Manipulations whidh go 
to Successful Picture-Making," in which he dealt dliietly with and 
domon8trat*id methods of retoucfhing tihe negative as a meaois of 
improving pictorial effect. Mr. Lawton a,ppeared as a stout 
champion of such methods, and showed by comparative examples the 
power which they afforded, and also the effects of their misuse. 

A hearty vote of thanks was accorded to him. 



PROFESSIONAL PHOTOGRAPHERS' ASSOCIATIOX. 
A MEETING of the Council was held on Friday, January 11. Pre- 
sent : Messrs. A. Basil, Gordon Chase, A. Corbett, C. F. Dickinson, 
A. Ellis, S. H. Fry, W. E. Gray, R. Haines, A. Mackie, R. N. 
Speaight, Lang Sims, F. G. Wakefield, Frank Brown (Leicester), 
W. B. Chaplin (Windsor), A. H. L. Chapman (Swansea), T. Chidley 
(Chester), and H. C. Spink (Brighton). 

The draft of the annual report of the Council was read and passe J 
for printing and circulation to members. 

The Hon. Treasurer gave particulars of his balance-sheet for the 
past year, showing that the subscriptions paid was the highest 
number collected since the Association was established. 

The death of Mr. F. A. Bridge, who was one of the founders of 
the Association, and had served on the Council 1901-10, was referred 
to, and it was agreed that his executor should be written to express- 
ing the regret of the Council. Among the cases in hand for members 
were a complaint against a firm of dealere in second-hand apparatus, 
an important case arising from the sale of old negatives involving 
an important legal point; a complaint against a firm of enlargers 
and trade printers ; a claim against a member by his customers for 
delivery of negatives taken in the ordinary way of business. 

The president read correspondence relating to the Lang Sims 
scheme, and also a letter from a member urging the Council to 
oppose the inclusion of "photography" among unnecessary trades. 

At the conclusion of the business a special Council meeting was 
held, in accordance with Rule 12, to nominate officers for the ensuing 
year. 

^ 

A Basnet Wall Calendar. — ^Messrs. Elliott and Sons, Ltd., 
Park Road, Barnet, Herts, send us a specimen of a most attractive 
wall calendar for 1918, of which they have a limited number for 
distribution to their professional customers on application. The 
calendar, while giving prominence to the Barnet manufactures, 
bears a most attractive study of a girl's head in colours, by Philip 
Boileau. 



Commercial JiCegal Inielllsence. 

♦ — 

A Photo-Canvassino Swindler.. — At Blackburn last week, 
Lionel Harris Goldberg (forty-three), of Edge Lane, Liverpool, was- 
charged with obtaining by false pretences from Harriet Howard the- 
sums of 2s. and 3s. (twice), and also Ss. 6d. from Elizabeth Keogh, 
and 4s. 6d. from Lily Weaver. All the alleg«d offences were irv 
December. 

Mr. J. G. Radcliffe, who prosecuted on behalf of the police, said 
that in all the cases the methods of prisoner were much the same. 
He set himself out as the British Enlargement Company, and on- 
seeing photographs on the walls of the homes he visited he sug- 
gested it would be a nice thing to have them enlarged and framed. 
He would obtain sums on account, and promise to bring the enlarge- 
ments and frames. In two of the three cases neither enlargement 
nor frame was received, but in one case the enlargement was- 
delivered, and aftei-wards taken away because the owner decided 
to have it framed. As the frame did not come, Mrs. Howard went 
to prisoner's so-called place of business in Butler Street, Blackburn, 
but found he had left. She also ascertained that there had been, 
neither enlarging nor framing there, and that prisoner had left 
owing his landlady 12s. Goldberg was very smartly traced by 
Detective-Sergeant Barnes to Liverpool, where he was arrested. 
He (Mr. Radcliffe) asked for heavy punishment. 

The Magistrates' Clerk said prisoner had put in a statement- 
blaming the drinking of his second wife for his downfall. 

When the landlady was asked what sort of woman prisoner's wife 
was, she replied that she seemed to be a very decent woman. She- 
was never intoxicated. 

Chief Constable Hodson remarked tliat prisoner, his wife and 
family came to Blackburn last November. Since his arrest there 
had been twenty-one complaints about him. He was wanted by 
the Leeds police, who had had seventy-eight complaints, and also- 
by the Manchester police. He enlisted in the Army in April, »nd 
deserted in May. He had been convicted at Hull, Manchester, and 
Longton for various offences, including false pretences, and neglect, 
of family. He was a travelling swindler. 

The Bench passed sentence of three months' hard labour in each, 
of the three c£tses, the terms to run consecutively. Aldermaui 
Green, Chairman of the Magistrates, said they were sorry they 
could not give him more. 

At the London Bankruptcy Court recently, before Mr. Regis- 
trar Hope, an application was made for the discharge of Chester 
Park Crawford, described in the receiving order as C. P. Crawford, 
of " Cameragraph," Craven House, Kingsway, W.C. The state- 
ment of affairs filed by the bankrupt disclosed liabilities amount- 
ing to £9,829, and assets nil. The bankrupt had failed on two- 
previous occasions, viz., in 1905 and 1910. He came to this country 
from America in 1907 with the idea of opening up and running a, 
number of skating rinks in vai'ious parts of the country. In 1912 
he was engaged in a scheme for ibuilding and renting music halls 
in France and Belgium, and lost £512 over the venture. Subse- 
quently he secured from an American company the right to seJI on. 
commission a certain -photographic machine called the " Camera- 
graph." In 1915 he sold his interest in the concern to a company 
called the Cameragraph Sales Agency, Limited, which company 
was formed with a capital of £5,000. Some of the shares in the 
company were sold for £358, whilst others were handed to people- 
who had rendered him assistance. He acted as managing director 
of tlie company until March, 1917. The official receiver reported, 
that the debtor had committed the following offences against the 
Bankruptcy Act : That his assets were not of a value equal to 10s. 
in the £ on the amount of his unsecured liabilities. That he hadi 
contributed to his failure by rash and hazardous speculation, and> 
that he had failed on two previous occasions. Eventually the- 
learned registrar suspended the discharge for four years. 

Legal Notices. — Notice is given tliat the names of the Bon. 
Marche Studios, Limited ; Pembroke Studios, Limited ; Photo- 
Telegraph and Cable Company, Limited ; and the Usa Photo. 
Papers, Limited, have been struck off the Register of Joint Stock 
Companies, and are .iissolved. 

Notice is given that at the expiration of three months from. 



January 25. 1918] 



THE BRITISH JOURNAL OF PHOTOGRAPHV. 



47 



Jacoarr 18 the names of the Belgian Artists. Limited ; Dean 
Engraving Conpany, Limited; International Artists' Club, 
Limited : Photo-Dnuna Company. Limited ; and the Whitefriars 
Sti«di«, Limited, will, unleu came is shown to the contrary, be 
«truck off the Register of Joint Stock Companies, and will be 
dissolved. 

Correspondence. 

— • — 

• * Cvrmpimdtntt thotdd ntter ti-rite on boA sid** of the paper. Ho 
notiet it taktm of eamtmimieationi ttnjsss the nantft and addrttn* 
or ih« wriUrt or* gimmt. 
".* W» io not umltrtalto rttpoiuibilUii for ths opinion* ecc p n ta td bg 
tmr eormmamdrnU. 
ROTAL NAVAL AIR SERVICE— PHOTOGRAPHIC 
SECTION. 
To the Editors , . . 
Qenilemen, — I notice that in the " Anawera to CorrMpondenta " 
(page 36) of the cnrrent issue of the "British Journal of Photo- 
graphy," a reply to a correspondent aUtea that applications for 
riitry into the Photogi»phic Section of tha Boyal Naval Air Service 
•hould be made to " Officer Commaoding Photo Section, 45, Vic- 
ttiria Road, Chingford." 

I have to point out that this is an-«rrar.' All applications for 
entry into this section should be addresaed aa follows : — 
Th« Officer in Charge, ' 
Photographic S«etioiis.R.N.A.S., 
"Whitehafl," ;■,, 
Chingrford, B.4.' 
— I am. Sir. youn faithfully, PEiirr B. Mnutiu, 

Lieut'-Camdr. R.N.V.R.,'T»ffictT-in-Cb»rge. 
"Whitehall," Chingford. E.4, EKurx, iIano«ry 19. 1918. 

WWTE BACKGROtNDS IN SK£TOH PORTRAITB. 
To tha EdiloM. 
Gentlemen, — I notice the subject of the white hackground has 
a^in cropped up. I am certain a great deal of tha difficulty is 
liroui{ht about by internal reflection in the Una (roip tha white 
■Tunrlting card in front. The shad<>.i:s of the figur* get clogged op 
Ikffore sufficient density is obtained in the gnumJ. I got over the 
■HiW^nlty myself by, taking out thr back cnmbinatinn. and paaa on 
■ •. for what it is worth. Where the studio is too short for 
< to this 'method a single Iwna of suitable focus could be 
used: 

And this laoda.on to another sabjert— ^i. , the folly of the average 
photographer's respect for li' " lenses. Abeotutely «s 

ftoA work can be done witi. iivap IrnsM. What the 

. ill., wants — the ordinary puUk .is u«U a« the moat hiKhly 
' : .'lit sectiftit (A it — is e«pr iT .in. always expression; it does 
ii»t really care an Indian dam atMiiit a hundred little finirkinenaes 
that seem to perplex a large majority of our craft. Human 
psychology more than any other of the " ologiee " is the study fur 
suoh of ua as wmiM rxcel. — Yours faithfully. F, FiXDUiT. 

Stadio-oo-t' \T Aacbtcrmuchty. Fife 

•luMMr- 



.MISSED BrslNESS. 
To the EditofB. 

Gentlemen, — Permit me to confcrataUte you on again soandini; 
the gong against raids by trickery, made principally by the White- 
rAapel fiatemity on the legitimate bufinem of photographers. 

It has always been a surprise to me IhAt the R.P.S. has not inte- 
rtated itself in the nutter, and (<inn<l means to protect their mom- 
brrs and the public against constant misrepreaentation. I am pf 
opinion this could be done now thrn> ia a shortage of materials by 
stopping tha cheap paper manufactortn. 

llie root of the troable ia competition. I believe the producers 
•>( tbeae funereal borron would welcone • " Controller " to keep 
them aU in lina. 

Many of them are capable of proJucing good work ; a little extra 
trniible and a little cxtrs expense and they could command twica 
the price, with credit to themselves and latisfartion to the public 

Toern and coontiy have been flooded with " soot and whitewash " 



memorials sad enough to make our gallant heroes rise from their 
graves as a protest against framed "ghosts" hanging to their 
memories. 

I hope the god of war will include in his reforms the extermina- 
tion of these cheap and nasty enlargements, together with the gang 
of canvassers who have been such annoying pests for years past. — 
Yours truly, a. Vernon Godbold. 

98, St. .\saph Road, Brockley, S.E.4. 
January 21, 1P18. 



ilnsiDers to Corr espondents> 

SPECIAL NOTICB. 

f« tomequtnet of feneral reduced twppliu of paper, at tht rent* 
of prohibition of the importation of much vmod pmlp and frati, 
a imaUer tpaei will be available MntU further notiee for repliet 
to eorretpondentt. 

Horeover, tee will antver bf pott if stomped and addretttd enve- 
lope it entiottd fo r rtplf i B-eent International 0o%tpon, from 

readtrt pitroad. 

s ^ * — ~ 

Tht fuU fuettiont and otmgers letft be printed onlf in the tate of 

tnqwir%»t of funeral interett. 

Queriet to bt antwered in the Fridaf'i " Jommal " mutt reach u* 

nM later than Tu etdaf (potted Monday), and ihould be 

addretttd to the Bditort. , - '* 

B. A. O. — 220 v, half-wstt lamps are not the slightest good on a 
aOO_v,cir<iiiY. If anything, half-watts require to be slightly over- 
run — i.e., work on a circuit of a little higher voltage than tliat 
for which the lamps are made. 

"T. E. S. — The best little book you can have, and, in fact, the only 
one, is " The Portrait Studio," a reprint, with additional matter. 
from the " B.J.," illiutrated, - with diagrams of studios and 
ooceoorie*;; price 7d., post free. 

J. 8. H. — There are no books on stereoscopic njiotography in print. 
You might possibly be able to obtain a second-hand copy of 
"Stereoscopic Photfigraphy," by F. Drouin, translated from the 
French, from a firm like Alessni. Foyle, second-hand booksellers. 
Charing Cross Road, lliere is another, No. 98 of the " Photo- 
Miniatuie,'' but it is uot obtainable at the present time except 
direct from Tcnnant and Ward, 103, Park Avenue, New York, 
I'rice 25 cents. 

E.vrLoSKO Abc Glasses. — 1. Can yon inform me what to use to clean 
the globe of an enclosed arc! 2. Also the means to refresh or 
whiten the asbestqs of the arc reflector? — Akc. 

1. Methylated spirit well rubbed pver will clean off a lot of the 
deposits, but to make bright, the best thing is a little hydrofluorie 
acid, rubbed in with a tuft of soft paper. Acid is very corrosive 
of skin, so exercise care. 2. Mix ordinary whitening with skim 
milk and apply with a, brush. 

H. and D. — Will you kindly answer the following query? I have 
soDe pinchrrKiiutio plates niaiked 250 11. and D. I wish to know 
the speed of these on the Wynne Meter and how to make the 
— snMjation for myself in future. — A. D. 

tl you want a working comparison we should say 80 to 90 
Wynne, but there is no regular rtile for conversion of H. and D. 
into Wynne Bptf€<l8 owing to differences in the way in which 
H. and I). s|H-ed nunVbevw are detennined. 

E. P. — Vignettoa in machine printing by strip and other machines 
are very larerly put in on the glaas-side of a negative with an 
air-bruxh, using a quick-drying coloured varnish such aa you can 
get from the Aerograph Co., 43, Holborn Viaduct. Failing your 
own facility in uxing an air-brush, we should say the beat means 
would be Ui ^et a few vignette glasses made up, cither on tissue 
paper aflixed to glass and treated with a stump and opa({ue. or 
done for you with an air-brush by one or other of the trade firma 
who go in for air-brush finishing. 



48 



THE BRITISH JOURNAL OF PHOTOGR.\PHY. 



[January 25, 1918. 



C. B. — In order to find the F. number, it would probably be suffi- 
ciently accurate for your purpose to focus the lens on a distant 
object, say a church spire half a mile away, and then, without 
disturbing the focus, measure the distance from the lens dia- 
phragm to the focussing screen. Divide this distance by the 
diameter of the largest stop, and you get the F. number. We 
do not see how we can tell you to distinguish different types of 
lenses. The ability to do so is simply the result of long 
experience, as in secondhand dealing of various objectives. 

AI. B. — Very likely the greater closeness of the plates has something 
to do with air-bells sticking to thein> but we do not think it is 
enough to account for the difference you find between the two 
tanks. We have had the same trouble in using porcelain tanks 
in which the plates were comparatively far apart, and then we 
got over it entirely by ceasing to lower the plates into the tank 
after the developer had been put in, but, instead, putting the 
plates in first and " dumping in " the developer solution 
vigorously. We would sometimes pour off the developer and 
immediately pour it back again, and found that we got absolutely 
no air-bells when following this plan. Perhaps lowness of tem- 
perature also has something to do with your getting air-bells 
under present conditions. 

A Nil.— We see where part of your trouble is. Pixibably the 
Dallraeyer 3 D. which you are using is much too long in focus for 
the enlarger. The best focus for a half-plate enlarging lantern 
is 8 or 9 inches. If you could use an //4.5 anastigmat of about 
this focal length you would probably find that your exposures 
were very much shorter. If such a lens is not available, the best 
alternative would be a cabinet portrait lens of //4 aperture, which 
might be of focus up to 10 or 12 inches. This would answer per- 
fectly for enlarging portrait negatives, but would not be so suit- 
able as the anastigmat for negatives of subjects where you wanted 
sharp definition right up to the margins of the enlargement. We 
think that by looking after the lens question, in conjuction with 
a good light like the " Howellite," you will be able to bring your 
exposures down to a reasonable time. 

Zeiss Triplet. — A friend has shown me a lens with the following : 
" Carl Zeiss, Jena Triplet 1 : 48, F50cm." on it. It is large, the 
glasses being 4in. diameter, iris diaphragm. Focus about 14 ins. 
Has yellow screen on front. Evidently fitted in aluminium. It 
is daimaged in metal parts, and iris is not working, but glasses are 
in perfect condition. Can you say what was probably the original 
value of it ? — Fbiend. 

The Zeiss Triplet lens was placed on the market about 1891, of 
aperture //6.3, but we cannot reconcile the data you give with 
those published in the price lists then issued. Apparently the 
longest f'ocus which was supplied was 16^ inches {= 41 cm.). If 
your lens is correctly marked, its focal length should be 19j inches 
(= 50 cm.). The 164 "^- lens was originally issued at a price of 
£20, but, owing to its early withdrawal, there are so few of these 
lonaes about that it is impossible to say what is a present price 
for it. 

ENLAEomo WITH Half-Watts.— 1. Is a 100-c.p. half-watt lamp a 
satisfactory illuminant for half -plate lantern with condenser? 2. 
Would a. 1,000-watt lamp with ground glass screen give a light 
which could be used without a condenser for enlarging? — A. B. 

1. The ordinary pattern of half-watt lamp — that is, with the 
circular form of filament, is not a good one for enlarging with a 
condenser. You want a focus type of lamp for this — that is, one 
in which the filaments are brought within a smaller area, but we 
learnt only recently that they are not now being made owing to 
the great call for the ordinary pattern. 2. Yes, a very goo 3 
illumination can be got with a high-power lamp placed in a box 
with white walls and with a screen of ground glass or flashed 
opal an inch or so from the negative on the side towards the light. 
In the "B.J." of March 30 last, also in the forthcoming 
" Almanac," is a description of vertical enlarger arranged with a 
lamp of this kind. 

Dallmeyer Portrait Lens — 1. I have got a 2 B Dallmeyer patent 
portrait lens, but I don't understand its working. Could you 
oblige me with an explanation? When I focus on the outside of 
a plate the centre is fuzzy, and when I focus on the centre the 



outside is fuzzy. Around the back end of the lens are four groups 
of notches, which I think has something to do with it, but I can't 
find out how. 2. Can you tell me, also, where I can get a studio 
camera shutter of the circular bellows pattern refitted with a, 
bellows, and about how much it would cost? — D. Anderson. 

1. Portrait lenses of large aperture, such as the Dallmeyer 2 B., 
usually have a very round field. You must, however, recollect 
that the lens you have is only sold to cover C. de V., and must be 
stopped down if used on a larger plate. The notches on the back 
cell are to indicate the amount of unscrewing when the diffusion 
of focu.s arrangement is used. For sharp definition the focus, 
notches must be opposite the little peg in the other part of the 
back cell. The more the notched portion is unscrewed the softer 
tlie definition becomes. 2. You can get the shutter repaired by 
the Altiincham Rubber Co., Altrincham, Cheshire. 



LiLYwniTE Delivery by Coal Gas.^Mbssts. Lily white Ltd., so 
we noltice from a recent para^aph iin " Motor Cycling," ore making 
use of the now verj' common " gas-bag " for tihe motor used in Hiv 
delivei'v of their commercial photographs, etc. A B.S.A. motor- 
cycle has been adapted for use witfli gas, and has proved satisfactory 
even upon tlie steep gradients which are to be found in Halifax and 
the aieighbourhood. 

Revised Camera Prices. — iMessrs. Horughtons, Ltd., send us a 
twelve-page list of revisions of prices of cameras, the figui'es in whicfi 
will serve to correct those in the latest large list of the firm, namely 
that of 1915. A 1918 edition of the " Ensign " catalogue Ls in course 
of preparation for issue in March, and will be oWtainalble by dealers 
at the rate of 15s. per 100 copies, indluding tlh© printing of dealer's 
naime and address on tihe back outside cover. 

Mr. J. E. Ellis, photographer and photographic dealer, of 
Valletta, is, we are glad to see, among those whose names are pub- 
lished in the Malta "Government Gazette" as having rendered 
valuable services in connection with the war. Mr. Elks, it is par- 
ticularly mentioned, has provided relatives of Service men buried in 
the Malta cemeteries with a photograph of the grave free of charge, 
and in other ways has rendered assistance to the sick and wounded. 

Wh fSnttsb lotimal d ^Ifotog^ta^fij^ 

The 01de§t Pbotoiiraphic Journal in the World. 
PUBLISHED EVERY FRIDAY. Estjiblisbed 1854. PRICE TWOPENCI 

Net Prepaid Line Advertisements, 

THE ADVERTISEMENTS ARE CUSSIFIED AS FOLLOWS: 



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SlOOND-HAND APPAAATTTS rOB SALX AND WAHTSD— 

Private. 
Kkw and Second-hand Apparatus roR Sau aitd 

Wanted — Trade . 
Materials. Sundry goods, papers knd postcards* 

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MiscELLANEOTTB. InstructioH, personal, enqoiries* 

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24, WeUlngton Street. Strand, LONDON, W.C. 2. 



THE BRITISH 



JOUMAL OF PHOTOGRAPHY. 



No. 3013. Vol. LXV. 



FRIDAY, FEBRUARY 1, 1918. 



Price Twopence. 



contents* 



■sCatwumu *9 

BoixTirio DsnoH ni Omcu. 

Punjmano*. By J. A. Onoc* . ■ U 

ComioBT or Aaiaicix Pboto- 
•kAraa m Ouat BaiT*» ajiv 

Obtaib Bsrrwa Pnaaavioat. . U 

T&AiMiHo la Arri-iBP Oyncii .... 54 

CiHiuno» M 

PinxT iliw* SS 

A«llHfft SS 



VAUK 

. 96 
. 57 
M 



N»<«» »»i> NoTr« 

roKraooaiaa Bxaiamom .. 
CoitacwoasBao — 
Air-BalhlaTaak D***topiiwnt 
- ABMticmto u4 OttMr 
LiMM — Ani*rt<UM ud 

CJopTTkbt » 

. M 



rk« fluwary o^ w w te i it i which utuallf peeupitt tht loietr half 
«f thi* odImwh «iU U Jcnmd at On foot cf Ut* pagt overUaf and 
mil e6mlmu» to b* plaetd thtrt whiUt iU rtguUtr po$itiim u rt^ired 
for notieot rtiatimf to ths fiirtkeom mg " B.J.AlmMoc." 

Wh«n to 0«t th« Almanao. 

In these noles last week it was said that the date of pub- 
lication of the Almanac would be announced at the earliest 
opportunity. We then anticipated that such could be done 
in this i«ue. Unfortunately, at the time of writing it is 
not possible to state the day precisely. Equally, we cannot 
defer the announcement until next week because very 
likely the Almanac will be on <«ale before the " B. J." of 
February 8 reaches its readers, and if we waited until then 
we should have failed in our promise to notify the public 
•xaetly when the 1918 Alman<i<- will reach il>-.i!or-: in the 
United Kingdom. 

On the horns of tins dilemma wnat we iiad rx'tier do is 
to say that, judging from present snpplies, the Almanac 
should be on sale at the same time as next week's " British 
Journal." It may be a day or so later; ou the other hand, 
it may be a little earlier. At .iiiy rate, this is the beet we 
can do in the way of advertising to our readers when they 
should call in at their dealer'x to secure copies before" the 
verj- limited mirplus supply N exhausted. We are all 
nowadays familiar with tfip nt^reotyped retort of the 
grocer or butcher — "None tn ''.Tro " T? jq nearly the 
same as regards the Almanac 

We should repeat here the ri'iily which our publisher?! 
have had to maJce during t)i" pa.^t few days to many in- 
dividual applicants — vix., that ik> more copies are now at 
their disposal. Sales are in tli>< dealem' and booksellers' 
hand^. and if application be made promptly at these 
eotahlishments it will be possible, we nope, for the great 
m.Tiority of would-be buyer* of the Almanac to secure 
cnpip*. Some, we fear, mxifi ir" without, and it is our 
rri;ref that we can do no nmr" than -tate plainly how 
thing* stand. 



EX CATHEDRA. 

Over No matter what skill may be exercised 

Development, iu lighting and posing a sitter, it is aU 
wasted if it is not faithfully rendered in tie print. The 
exposure may be correct, but if the development be 
carried even « little too far the scale of tones is altered 
and the picture suffers more or less, and it is generally 
more. One of the principal differences between really 
good and merely ordinary portrait work will be found 
in the quality of the high-lights, those of the face being 
the most imiportant, while the draperies are hardly of 
leas consequence. In the good portrait the flesh has its 
true value and texture, and the draperies give some 
suggestion of the material of which they are composed, 
while in the poor one these delicate nuances are lost, and 
the result is as if a coloured plaater-cast had been photo- 
graphed instead of a living person. This defect may occur 
from over-lighting, but in the winter it is generally due 
to a poor light, which gives a picture lacking in round- 
ness. And this is made worse by the use of too warm a 
developer, which rapidly penetrates the film and chokes 
the delicate shadows in the lightef parts of the subject. 
When the average operator uses warm developer he is 
very apt to overdo it, and to work at a temperature in 
excess of that prevailing in the summer. Recently we 
had the curiosity to test the temperature of the solution 
a young assistant was about to use, and found it to be 
about 85 deg. Fahr. It was, therefore, not surprising 
to find that the negatives he had already developed were 
of the plaster-oast variety. The only safe way to obtain 
uniform quality is to develop for a fixed time at a fixed 
temperature. Judging by looking through the negative 
or at the back of the film is an unsafe practice, for a 
plate usually has a thicker coating of emulsion at one end 
than it has at the other, and it is just an even chance 
whether the face falls on the thin or the thick end. 



Americana' We are very much obliged to Mr. 

Copyright in Robert Wallace, the honorarv secretary 
BPTtain ^f tjjg Scottish Photo-Pictofial Circle;, 

for calling our attention, as he does in the letter which we 
print upon another page, to the Order in Council of 
Febmarv. 1915, which has definitely stated the conditions 
to be observed by American citizens or persons resident in 
the United States in order to secure copyright protection 
for their work (photographs) in this country. The text 
of the Order shows that the interpretation which we laid 
upon the earlier and more general proclamation is not the 
correct one. Our American friends should therefore notice 
that it is neoes.sary for them to resrister the copyrifrbt in 
their photographs at Washington and to comply with the 
United States regulations in the matter of marking puh- 



50 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[February 1, 1918. 



lisbed copies just as they are accustomed to do for the 
purpose of legally sustaining copyright in their own 
country. The arrangement is, in fact, something between 
that which was originally contemplated in such individual 
reciprocity agreements, and that which is embodied in the 
terms of the Berne Convention. As Mr. Wallace very 
truly says, the provision of the opportunity for addition 
to an Act of Parliament by Order in Council provides 
opportunities for adjustments of this kind. Unfortunately. 
Orders in Council are not widely published, and unless 
the practice is adhered to of studying each issue of the 
" London Gazette," the introduction of modifying legis- 
lation may fail to be noticed. 

* * » 

The Art of The great bulk of the British public 

Selling — believes that making sales is a very easy 

matter, which is within the reach of any untrained person, 
being in fact as simple as poking a fire or editing a news- 
paper, either of which performances the looker-on feels 
that he could do better than the man who is holding the 
poker or filling the chair. This is true in a limited sense 
as far as salesmanship is concerned, as the popularitj' of 
slot-machines proves, always provided that the customer 
requires just what the trader has in stock and that the 
latter is satisfied with supplying that and no more. We 
fear that many receptionists belong to this class, and that 
business suffers accordingly. The photographer, usually 
no salesman himself, is fairly well satisfied with the busi- 
ness done, because he is kept busy and making a comfort- 
able living, but does not realise that a live saleswoman 
could, without increasing his overhead expenses, add a 
very substantial percentage to his profits. 



—and a New Some time since a friend had the mis- 
Receptionist, fortune to lose his receptionist, a lady in 
whom he had a well-deserved confidence, and engaged a 
successor, whose quiet demeanour did not indicate any 
special talent. He was quickly undeceived. Her first 
action was to overhaul his stock of frames and other 
sundries, and to ask for specimens mounted in certain 
styles. In a few weeks he found that without increasing 
the number of sittings, the takings had grown considerably. 
The demand for the better classes of work was greater 
and the sales of frames, miniatures and enlargements had 
greatly improved. The reason was that the new assistant, 
instead of being merely ]X)lite and obliging, had a quiet 
enthusiasm in her work, and was able to direct the wants 
of the customer to the lines in which she was interested, 
without gush or apparent pushful ness. The most successful 
salesman of photographs we ever encountered had learned 



J 



the art of selling in a jeweller's shop. Knowing little of 
photography, he had a good knowledge of psychology, and 
found the handling of a certain class of people as easy in 
the .reception-room as at the jeweller's counter. The 
receptionist who wishes to earn a good salary or commission 
could do worse than to take a course of salesmanship at 
one of the many business training centres which now exist 
in most large towns. 



Muddy With hypo at the present price there is- 

Prints. danger of an inclination to overwork 

the fixing-bath before transferring it to the residues. 
Theoretically, iiypo will dissolve a much greater quantity 
of silver than is desirable it should do before it is discarded, 
for it is not only saturation with silver which is to be i 
avoided, but the introduction of other matter which causes 1 
trouble. Now that bromide and gaslight jiapers are used 
so extensively the fixing-bath sometimes becomes loaded 
with developer and a degradation of the high-lights gradu- 
ally appears as a consequence. Many printers transfer 
their prints direct from the developer to the hypo without 
rinsing, and at the end of a day's work the fixing-bath 
contains a pint or more of amidol or melol-hydroquinone 
solution. If this were poured in in one dose one would 
throw away the solution and make a fresh one, but the 
effect is the same if it is added a drachm at a time. This 
is often not recognised until the mischief is done, and 
dirty-looking prints are coming through. If a printer 
starts with, say, twenty ounces of developer and finishes 
witii only ten ounces in his dish, the balance must be some- 
where, and if the prints are not well rinsed, it is in the 
fixing-bath. If a plain solution of hypo be used the con- 
tamination soon becomes visible, but with the acid bath 
now generally used the danger point is often long passed 
before it is recognised. Economy in hypo is too dearly 
attained at the cost of inferior prints. Another point 
which many printers are not careful over is the contamina- 
tion of the developer by hypo carried into it by the 
fingei-s. The gelatine-chloride worker had perforce to keep J 
the hypo solution in its proper place, but there is now J 
arising a generation to whom it has no terrors because its 
evil influences are not so immediately apparent. 
* * * 

Knifing Not so long ago the retoucher who could 

Bromides. use the knife effectively upon a negative 

was the exception, but now every practitioner of any pre- 
tensions is presumed to be an expert in this direction. The 
print finisher has not adopted the knife to the same extent, 
vet it is easier to work upon a matt-surface bromide than 
it is upon a negative. The procedure is very similar in 



SUMMARY. 

A lecmt paper before the New York Society of Illuminating 
Engineers has dealt with the design of optical systems for the pro- 
jection of ordinary lantern slides or for moving-picture film. The 
author, Mr. J. A. Orange, discusses alternative schemes, represent- 
ing systems which vary according to the size of the light-source, 
description of condenser, and aperture of projection lens. (P. 51.) 

.■\propos of our recent reply to a correspondent as to the avoidance 
of air-bells in tank development, the Eagle Tank Co. prescribes rinsing 
plates before placing in the developer and, further, removing surface 
iiir-biibbles from the developing solution (before inserting the rack of 
plates. (P. 58.) 

In efforts to economise hypo, quaJity of fprints may suffer as the 
result of carrying developer into the hypo bath. The'old practice of 
rinsing prints between developing and fixing appears now to be much 
less common. (P. 50.) 

E.\cessive temperature of developer is often an unrecognised cause 
of flatness of gradation in portrait negatives. Not infrequently it 
creeps in as the result of over-warming the developing solution in 
cold weather. (P. 49.) 

Photographs showing the part taken in the war by the City of 
Birmingham are now being collected Iby a photographic sub-com- 
mittee of the War Memorial Museum. (P. 57.) 



Our speculation of last week, as regards conditions nnder whidi 
.\merican photographs secure copyright protection in this country, is 
contradicted hv the terms of an Order in Council issued as long ago 
as 1915. Mt. R. Wallace, of the Scottish Photo-Pictorial Circle, calls 
our attention to this Order in a letter on page 59. The full te.\t of 
the Order will be found on page 53. 

" CoLotTK Photography" Sttpplkmbst. 

In a recent paper before the Royal Photographic Society Mr. A. J. 
Bull dealt witli some interesting phenomena of absorption and trans- 
mission of colour by various media, and instanced the effects which 
j)eculiarities of absorption or transmission produced in the photo- 
graphy of coloured objects. (P. 5.) 

The" current instalment of the " Deeennia Practica " of colour 
photography takes the form of a resume of the methods and formulie 
which have" been recommended and practised for the extra-colour 
sensitising of Autochrome plates. It is to be noted that these (pre- 
wur) formulae prescribe enemy dyes now largely replaced by British. 
(P. 6.) 

The Prizma process of colour cinematography, described some- 
months ago in the "Sup]jlement," appears now to have been simpli- 
fied to a form in which it differs very slightly from previous processes 
planned upon the same system. (P. 8.) 



Februarj- 1, 19iaj 



THE BRITISH JOURNAL OF PHOTOGRAPKV. 



51 



earh rM«. The gelatine film must be absolutely dry. so that 
portion of the image to be removed comes away in 
■ ier ; the knife must have a razor-like edge, which must 
be kept at right angles to the paper, and the scraping 
must be done very gently, so as to avoid chipping off the 
coating. A knife skilfully used is to be preferred to any 
method of using abrasive powder or erasing rubber as is 
often recommended, as the work .-an be kepi closer to the 
outlines of the subject and tlie surface is less disturbed. 



We have seen a skilful finisher by this method work up 
a dark enlargement using an ordinary penknife, clearing 
up heavy shadows and introducing lights iu a way which 
appeared marvellous to the uninitiated. A great advan- 
tage over touching witli body colour is that, as nothing is 
added to the original image, there is no change of colour 
even if the print fades slightly. It should be remembered 
that scraping is the most effective way of lightening aero- 
graphed work whicli cannot be cleanly removed with water. 



SCIENTIFIC DESIGN IN OPTICAL PROJECTION. 



A w«ek or two »go we quoted from » paper before the New York Society of IlIiiiuinatinR Engineers on a system offreguliitinrr 
illumination upon the projection screen in iiccordance with the conditions which roiike for the optical comfort of an audience. A 
further paper before the some Society now deals with a subject which has a much more important bearing upon optical projection 
inasmuch as it is an investigation, as regards eflective illumination of the projection serpen, of different systems of illuminating 
the lantern slide or other transparency. The author. Sir. J. \. Orange, of the General Electric Company, is presumably in- 
terested in showing the superior results which can be secured by means of some metallic filament lamps used in accordance with 
an optical system which is quite different from that hitherto employed for other light-souices, such as gas mantles, Nernst, and 
arc lamps. But as it appears that the use of a metallic filament lamp for optical projection is being actively develoiied and 
promises to revolotioniae the construction of optical lanterns, a study of the principles of projection as set forth by the author 
is certainly to be recommended to those who, after the war, will be retaming to the manufacture of these largely sold articles. 
The metallic filament lamp has much to recoininend it on the score of convenience and constancy in comparison with an arc, 
and if it tarns oat that its introduction for projection purposes is the occasion of displacing the familiar type of lantern con- 
denser from the rogue it has enjoyed for many years pant, it is obviously nccesnary that constructors in this country should keep 
before them what progresK is being made in this direction.— Eds. KJ.' 



'1 and 
r the 



As .1 preliminary to the discussion ■ 

movin^-pirtur*' projertor it is on 

question of the moat soit«b(e brif^tneas of the pi<«uie shown 

an the screen. 

This mstlfr has never btvn standardised, although there 
do«a n.>t wrm to be »ny particular olMtacte in the way of 
some agreMBent as to tiie mc^ dcwraU* brightness in the 
heariest sbad<>ws of a picture, exprrmcd as a function of the 
gvnenal room illumination. A combination of experiment with 
testH on theatrva ahoaJd seitle this jioint, but thv conner-ion 
txtween such brij^tMH and the intensity of illumin»ti<>n 
vided by the projector (messumi in the natural way witli 
...a<- or fiUn out) is the aoame of much difficulty. 

The n>lati^>n rMto on two factors, on* Hm density of the 



nietre-i-andles) in tlie char parts, presumably with a musliii 
or while paint scrt^en. H. P. Gage, in tlie discussion on the 
same paper, givts some figures which seem to suggest 2.5 to 
6.0 fiHit-candles (27 to 65 metnMsandles) for magic-lanterns 
and 2.6 to 30 f<«t randies (27 to 320 metre-candles) for moving 
pictur««, again presumably on a matt white screen. 

K<.';;arding thef^t* figures it is infertfttirn; to note that a 
great many theatre« ujMTBte siiccessfuHy with less than 2.5 
f<H>t-candles (27 inetr»--caii<ll«8) on a j>lain screen and that one 
of the best known thintres in the country is o])^ating under 
ciimlitions equivalent to con»ideral>ly less tluan lO foot-candles 
(107 mt4jv-candU«) on a plain scretai. 

The r»T»rt of the Committee on dare', dealing with acreens, 
Migge4t>< a mean picture brightneas of ^ liatnbert (presumably 



-'■'If. or film an<l the other the nature of the screen. The j miUi-Iambert), with a factor of 5 either way. 
iier is »ery variaUe ewen in the mgular photographic 
-ioct, while the fariotu natural-colour achievesnents may 
into appalling densities. The most that can be done at 
Uuft time is to agitate for a standard deiwity in the ordinarj- 
photographic nTunU, thsre being little excuse for the e.\trenii« 
now mn to. The iiysd sliilea and films, mooidight and fire- 
light effects, ar» not a dkitarbing featui* because gloomineas 
is there part of the effect soaght. The natural-colour pro- 
.j,.,.t. '-.qaire a higher order of illumination and should be 
provided for nnlcas the rxhifaitor can contrive to 
•■^■m by rccoanie to »iich I'Xpedirfits as further 
the room, shortenint; uf the thT>>w ami substitu- 
tion oi a highly solortur w-rrjen. 

The mm.iining '-oriHideralion. '^itt-n character, is the om" 
determining ' "on betwerti intonaity of illumination 

and screen \r slide or film l>eing absent. 

Taking the white paint <>r muslin M-reen as s standard. th>' 
metallic or selective screen* oH«^ a factor' of from 1 to 7 
> re.,-.iriU pictnre brichtn«m. and where the design of the 
auditorium is appropriate they an- «Hry desirable. Taylor' 
s|M'.ili:<> of satisfactory slide prrijectifin with i-ft. candle (SI, 



I'l OsanIMM im ai*rp. " Diffi^lat M«4ia Prnjn 
Trut. t. E. a., p. «, Kow I. vol. XI. 

") Tarler, J. 8., "Tk* PrajMtini l^aatrm Ti 

T«l. ZI. 



and FocnMlnc Scrr»n*.* 
I. B. »., p. 414, No. i. 



This mMin value corrwsponds roughly with 2.5 foot candles 
(27 nietn'-candles) on a white paint screen, measured with 
slide or film out. 

There is exc»>ll<'iif reosiin for assigning an upp«T limit to 
the picture brightn<.«ti in the case of moving pictures; this 
|H>int will be referred to later. 

In its typioal form tlie magic-lanteim is an instrument 
adapted to the projection of transparencita-slides about 10 cm. 
in diameter. At different stages in its history it has been 
used soconsfully with such enormously different light-sources 
as the kcrrwene flame, the lime-liglit and the carbon arc. Even 
when allowance has been made for the ■ transparency of the 
old-tiiiM».alMn and the smaller screens of early days, it still 
reniain.s a jroniler that such diffea-ent sources should have 
sorv«l the purpose. „ 

Kor the projection of the slide there is used an objective 
lens system somewhat similar to a camera lens. One can say 
immediately that the highest possible illumination is pro- 
duced if one can contrive an extended background of source- 
surface behind the slide (Fig. la). In this ideal case the 
illumination at the screen, the slide being absent, Is 

A V It 

— -i- - X k where A is the apparent area of objective opening 

I'l tVaiiriiirr un Cllarr. " P Pn'li ( Miilia: Prrjccl^ou mil Foruieing Pcretra. ' 
Trant. I. R. 8., p. 92, No. 1, vol. XI. 



52 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[February 1, 1918. 



presented toward the particular sci-een-point considered, B is 
the brilliancy of the source, r is the tha-ow and k is the 
tnansmission coefficient of the objective. (As in the case of 
the searchlight tlie i>j)tioal system presents an area endowed 
with the brightness i)f the source, neglecting objective losses, 
and the area, the brightness and the remoteness determine 
the illumination at the [xiint in question.) 

If it were not highly uneconomical and inconvenient in 
many waj"s this arrangement would be the natujral form of 
miagic-lantean. In practice it is usual to use, not a back- 
ground of soui-ce-S'Urface behind tihe slide, but a background 
of len.'i-surface. Now, if tlwre is an extended source-surface 
behind this lens- -and at any distance, provided the source is 
indefinitely extended- then the lens-surface will ap])rar as 
bright as the original souTce, neglecting i-eflection and absorj)- 
tion losses. If the lens is convex, there can be found one 
particular position for the source-suirface at 'which a I'clatively 
sma-ll extent of source is corniiletetly sufficient. The result 

is a screen illumination „ - x ki, k^, where Ai is the 

coefficient of transmission of the [tuiitleiiser'] Itns — again 
simply a matter of absorption, etc. —and l\ is that of the 
objective. 

The lens which serves in this way is known as a condenser. 
Thfire is a simple way of demonstrating the possibilities of 
a condenser, viz., by sending light backwards from the front 
of the objective, the latter being teanporarily coveired with a 
piece of ground glass. By holding a piece of paper liehind 
the condenser one may explore the Jx>ssible source positions ; 
a circular patch of light is noticed wQiich va.ries greatly in 
size with the distance from the condenser, and the size of this 
patch indicates the maximum extent of source whicn is useful 
in the corTe.s.ponding position, any further extension of source- 
surface being without effect (Fig. lb). Any piece of glass 



(«:> 



-e 




-e 



{i) 



Pi(. 1, — (o). Extended background of Hghtsourje behind transparency without 
condeaaer. (bi Hmt'ler lii{ht-s3urce with use of condenser behind transparency. 

which is free from flaws and is of a generally convex form 
will function as a condenser, but it is another matter to 
design a condenser which will facilitate the use of an ex- 
tremely small extent of light-souirce. 

Standard jrractice involves the use of a pair of plano- 
convex [condenser] lenses ; in any particular case there is a 
limit to the degree of convexity which it is advisable to use, 
since it will be found that the more extreme foains call for 
a grtjater extent of source. A much better result is obtainable 
if one can use non-spherdoal surfaces for the condenser, the 
sharpest curvature being near the axis. Tlie difficulty of 
producing such surfaces commercially has restricted this 
development until very I'tcently. 

The limit of design on specially corrected condenser systems 
is I'eally deteirmined by the lens losses which increase more 
and more as the design (in effect, the number and convexity 
of the lenses) becomes extreme. 
The miagic-Iantern in this foi-m is a relatively simple 
instrument. Rational design nms somewhat as follows: — 
Knowing the size of slide and the average throw and screen 



size for which 'the outfit i? intended, the focal length of the 
objective is fixed. Selecting some stand.i.rd of illumination 
which the apparatus shall attain, making due a.llowance for 
the conditions under which it is likely to be used — such as 
<legree of general illumination and screen factor — there is next 
to be considered the means adapted to that end. 



The expression for the illumination, 



A B 



k involves areB 



of objective opening and brilliancj- of source, throw and 
coefficient of transmission (this latter covering both objective 
and condense^-). The two latter quantities are known i-oughly, 
so that one is left with a simple relation between objective 
Oldening and source brilliancy. The brilliancies of light- 
sources are extremely different, as has alreadj- been remarked, 
and it follows tliat tho size of the objective opening required 
wiill vary greatly. .Vttempts to use light-sources of very low 
brilliancy encounter the difficulty that extreme "aperture" 
in the objective is expensive and is subject to a fuirh/ 
definite limit citnsistent with satisfactory definition in the 
projected picture. This applies particularly to oil, coal-gas, 
and acttylene flames and the Wetlsbach lamp. There is a big 
gain in source brilliancy in going to the lime-light and Xernst 
latnp. The corre.oponding requirement in objective aperture 
is quite moderate, and, in fact, it is not so much their optical 
ciharacttir as it is general inconvenience which has limited the 
apiplioation of those sources. 

The result is that the source wiliich has been most commonly 
used until recently- is the oaiibon arc. Here we have some- 
thing which far tran.scends even the lime4ight and Nirnst 
lamp in brilliancy and the size of objective opening needed 
is very small. In consequence of this the arc lantern, as 
generally used, is contrivetl a little differently from the instru- 
ment so far discus'ed. 

A certain small aperture will suffice for the objective, and 
with the best choice of plano-convex condensers a certain size 
of source is then required. 

Now it follows from the existence of marked spherical and 
chromatic al>erration in the condenser that one may with 
advantage use an objective which is larger than is reallly 
necessary, but at the same time aD'aniging so tliat each screen 
point is served only by a small portion of the objective. 
Perhaps this device is more readily understood from a 
numerical example. Suppose that on the basis of arc bril- 
liancies it is concluded that 1 sq. cm. of Objective opening 
is ample. If one were to provide ari objective with that 
amount of opening and then add the most suitable form of 
plano-conve.x condenser it migiht be necessary to use an arc- 
crater 15 mm. in diameter. On the other- hand, it would 
be jjossible to use an objective 16 sq. cm. in area, of wliich 
only 1 sq. cm. would Ix? utilised by any particular screen- 
point ; this might be attained with jterliaps only 10 mm. arc- 
crater, using the same condenser a.rrangement. This alterna- 
tive arrangement is tlie one corresponding to the rule wliicli 
is given in books on projection, namely, that the convergent 
beam coming from the condenser shall penetrate the objectivi 
so that no ]>art of the beam sliall be obstructed by tli«> len.s 
mounts, etc. 

Another way of lucking at magic lantern design for ai'c ser- 
vice is to consider that there are three ways of getting the 
desired i^esults. 

(1) Use a very small objective, ;.n ordinary condenser and a 
large and expensive light-soui-ce (I'ig. 2a). 

(2) Use the small objective, an expensive condenser and ;i 
small, cheap light-source (Fig. 2b). 

(3) Use an objective which has a gross a])erture in excess uf 
the "effective" aperture for any field-point, a cheap con- 
denser and a small, cheap light-source (Fig. 2c). 

The choice is one that turns on relative costs of apparatus 
and rests with the maker; the third alternative is out of the 



K^.ii 



ialb. 



TWK. BRITISH JOURNAL OF PHOfOGR VPHV. 



53 



■ I :- -tion with sources of low brilliancy simv difficulty and i-x- 
|..n-e are encountered in attaining even the effective apt- rture 
tliey require, let alone anything larger. 

Recently the tendency has been tu substitute a tungsten lamp 

for the arc, and it is evident that this is sound practice. The 

• :rr=ten lamp in it« various spe<:ial forms offers a brilliancy 

J Mg from a value higher than that of the Nemst lamp up 

a value exceeding one-quarter of that of the direct current 

rnr -crater. There is no difficulty in getting ample objective 

ire for use in conjunction with such a source, hut it- 

to be remarked that erronooii^ conclusions may be drawn 




c«-y 



CD 



Cc) 



e 



.411 r-i' .1rn«#p 



FtiS AlMmaUT* An loawm Arrancnnonta. i*' Obj" i 

a l l— ». wwr* Uis«. <*| Ob)«cUT« imftll. oiilauvr roirr i-i 
Iri Ok|«etiT« Uis», CMidwiir ebasp, too re* inwll, 

from tests in which an outfit designed lor the arc is made to 
work with the incandescent lamp. 

To sum up : the old illuminants (acetylene, mantle lamps, 
etc.) hav« such a low brilliancy that in order to get good 
r«*ulta «xp«nsive optical apparatus is neoessaiy. and even then 
the poasibilities are limited. Between these illuminants and 
the more recent there is a gain in brilliancy of from 100 to 
1,000 f'lld. This ennrm-'iis zain r>-nd»>Ti> it easy to proviile 
optical equipment \<^ «ultk likely V> be 

needed. Questions ik- to the tore, and 

there is no doubt that the tungsten lamp is in much the 
strongest positiifO in the group (linw-Ught, Nvmst lamp, 
tungsten lamp, carbon arc). J. A. Oraxhe. 

(To bt continwd.J 



OPYRICHT OF AMERICAN PHOTOGRAPHS IN GREAT 
BRITAIN AND CERTAIN BRITISH POSSESSIONS. 
Ik order thorooghty to clear up thr - 'tained in 

the last paragraph of the article on -h Photo 

Kraphs in the Dliitad Stetc*. and in Aiiivncaii i'!i<'t»iira|ili< in (irrat 
Bntato," which aiifmiinl in the " B .1 " of .)iinaar>- 25 Uuit. «r 
reprint here the trit of tlw Onler ir ' ■ ! FVliruarv 3, 1915. 

by which the cnnditiona on whirh .\ni> ■•••it *rcure capyright 

this eoootry are definitely furmuUltMl. It «ill be seen that tlii- 
iMilc solwtanir of the Order ia oonlainrd in Sub-Sections i, and ii. 
uf S^Ttinn I — namrly. to the effect that photographs secure copy 
nglit here fu. a Ufmt which shall not rxceed that conferred by thr 
Copyright Law of the Tnited Slatrt, mid, lurther. that American 
citisena, a* a condition to securing copyright here, require to observe 
the fnrmalitin pmcribed by the I'nitod State* law. Theee are 
chiefly the regutration of pbnto(:Tai>h« at Washington and the 
markini; of puulishrd copies " oijijr i{ht." 

At the Court at /tuekini)li,ttn fnln^' the 3rH dav of Ftbrunrif, 
■ 115. 

PRESKN I 
The KINti'S Mmt Kx>.IIeni Majesty. 
Lord President. 
Viaooont Knoilys. 
Lord Ckaaberlain. 
Mr. Secretary Harciiirt 
Mr. Arthur IfenHrr^<>!' 
Sir William Ma. < 
Lord Justice Bai-. 



\\7 iERE.\S by a Proclamation of the PivsiJeiit cjf the United 

» » State< of America, dated the 9th April, 1910. the benefits of 
the United States Act of 1909, entitled " An Act to Amend and 
Cdiuolidate the Acts i-eapecting Copyright," were extended to the 
Subjects of Great Britain and her Possessions, but no provision was 
made therein for the protection of the musical works of British Sub- 
ject* against reproduction by means of niecimical contrivances : 

And whereas Hi.* Majesty is advised tlmt the Uovernment of tlie 
United States of America has undertaken, upon the issue of this 
Onler, to grant such protection to the musical works of British 
Subjects : 

And whereas by reason of these premises His Majesty is satisfied 
that the Cioveniment of the United States of America has made, or 
has undertaken to make, sucli provision as it is expedient to require 
for the protection of works entitled to Copyright under the pro- 
visions of Part I. of the Copyright Act, 1911 : 

And whereas by the Copyright Act, 1911, authority is conferred 
upon His Majesty to e.xtend, by Order in Council, the protection 
of the said Act to certain classes of foreign works within any part 
of His Majesty's Dominions, other than self-governing Dominions, 
to which the said Act extends : 

.And wher«"es it is desirable to provide protection within the said 
nominious for the unpublished works of Citizens of the ITnited 
States of .America : 

NOW, THEREKORE, HU Majesty, by and with the advice of 
Hi* Privy Council, and by virtue of the authority conferred upon 
him by the Copyright Act, 1911, is pleased to order, and it is hereby 
ordered, as follows : — 

1. The CopyriRht Act, 1911, including the provisions as to existinj; 
works, shall, subject to the provisions of the said .Act and of this 
Order, apply — 

(a) to literary, dramatic?, musical and artistic works the autlior.<: 
whereof were at the time of the making of the works Citizens of 
the I'nitcd States of .America, in like manner as if the authors 
had been British Subjects : 

(6) in respect of resilience in the United States of America, in 
like manner as if such residence had been residence in the parts of 
His Majesty's Dominions to which the said Act extends. 
Pn.vided tb»t — 

(i) the term of Copyright within the parte of His Majesty's 
Doniinions to which this Order applies shall not exceed that con- 
ferred by the law of the United States of America : 

(ii) the enjoyment of the rights conferred by this Order shall be 
subject tc the accomplishment of the conditions and formalities 
prescribed by the law of the United States of America : 

(iii) in the application to existing works of the provisions of 
Se«'tir)n 24 of the Copyright Act, 1911, the commencement of this 
Order shall be substituted for the 26th .Fuly, 1910, in sub- 
se'tion 1 (ft), 

2. This Order shall apply to all His Majesty's Dominions, Colonies 
and Possessioiu, with the exception of those hereinafter named, that 
is to say : — 

'The iJominion of Canada. 
The Cojnni'i-iweiilth of Australia. 
The Dominion of New Zealand. 
The Union of South Africa. 
Newfoundland. 

3. This Order shall come into operation on the 1st Hay of .Tanuary, 
3915. which day is in this Order referred to as the commencement 
of this Order. 

And the Lords Commissioners of His itajesty's Treasury are to 
gtrrtJU^uaaessary orders accordingly. 

Almtric FittRoy. 

Captain E. L. II. Dv-kkzhtov, whose name figures in a recent 
list of nUlitary honours, is doubciess' well-known to many of our 
readers as the son of .Mr. T. Dunkerton, architectural and porti^t 
phototrrafiher and view publisher, of 95, Portland Road, Hove. 
Captain I)unkorton, wlio has just been aw;irde<l the Mililarj- Cross, 
wa,; lieforn the war actively connected, almost from boyhood, witJi 
his father's bnaineas, and at the age of 17 successfully travelled 
Ireland in bis interests. In 1915 he enlisted in the Artists' Rifles, 
was mentioned in dispatches in .August last, and baa now received 
the .Military Cross for great gallantry under heavy enemy bnrrage 
fire. His age is now 22. 



54 



THE BRITI8H JOURNAL OF PHOTOGRAPHY. 



[February 1, 1918. 



TRAINING IN APPLIED OPTICS. 

American Plans to Dkvelop an Oitkal Industry. 

The first step in the eiioouragemejit and development of optical 
industry — viz., the training of men in the special scientific field of 
applied optics — is the subject of full recognition by Profe.ssor .lames 
P. C. Southall, of Columbia I'niversity, who, in the "Scientific 
American," recounts the steps taken in France and England, anJ 
impresses the necessity of similar measures being carried out in the 
United States. Professor Southall writes : — 

Within the past year an Institute of Applied Optics has been 
established in France under the able directorship of Professor 
Charles Fabry, which is to include (1) a college of optics intended 
to provide a thorough theoretical training for opticians and at the 
same time to cultivate among its students a taste and zeal for 
o|)tical research ; (2) an optical laboi-atory for exiperimental and 
testing purpose.s ; and (3) a trade school in optics with all the mo«.t 
modern methods an J appliances. The courses of study are said to 
be already under way. The transactions of the institute will be 
published in a journal devoted to optical science. Meantime a 
einiilai- project has been inaugurated in England by the establish- 
ment of a Department of Technical Optics at the Imperial College 
of Science and Technology in London. Professor F. J. Cheshire, 
president of the Optical Society of CJreat Britain, who has had large 
experience in optical matters, has been appointed director, and the 
courses of lectures have been advertised for the current academic 
session. The British Government and the Lonion County Council 
have aided the entei-prise with liberal grants. 

It is not without significance that this long-delayed step in both 
France and England is in reality a direct consequence of the war. 
The importance of properly organised manufacturers of optical 
glas,s and of optical instruments had been manife.*t. and the matter 
haJ been frequently and insistently brought to the attention of the 
Governmental authorities, but until the dire nece.xsities of war 
revealed the lack of optical preparedness little heed was i>aid to 
these representations. A writer in " Nature" (Vol. 99, August 2, 
1S17. p. 448). commenting on the situation, observes feelingly that 
"the thought of what range finders mean to the British Navy an! 
of how narrowly we escaped being dependent upon the enemy for 
our supply of these essential instruments, is almo.st enough to make 
one shudder, even unde; the wings of a Royal Navy that has swept 
the sea." Some time ago a Board of Scientific Societies was (U'gan- 
ised in England iby the Royal Society to investigate scientific and 
technological problems arising out of the war, and the first formal 
report to be issued by this body is entitled " National Instruction 
in Optics." The report, which was published in full in " Nature," 
March 1, 1917, and which is well worth reading, emphasises the 
necessity for immediate action, and asserts that "the next few- 
yea; s are the years which will letermine the future of the (optical) 
industries of the country." 

It goes without saying that the same reasons which have led to 
the establishment of these optical schools in France and England are 
equally applicable in the United States. If the optical industries are 
to be encouraged and developed among us, not only now but in the 
yeais to come after the war, there will be an increasing need of 
trained and experienced men with a more or less extensive acquaint- 
ance with the whole range of optics, both theoretical and applied. 
At present there is no university in this country where this special 
training can be acquired. In our colleges optics is studied merely 
as a part of physics and by students who have little or no concern 
with the manifold applications of optics in the arts and industries of 
the modern world. Not many of us pause to think of the aid which 
optics lends to the prosecution of scientific research in all its branches 
or its relation to the vital pioblems of human vision. In America 
as well as in England and in France optical science has had illustrious 
votaries whose work has become known all over the world ; but not- 
withstanding, it has come to pass that the great domain of applied 
optics has in modern times become almost exclusively a German pro- 
vince, not because the Germans possessed superior skill and genius in 
optics, but because they realised the great practical importance and 
far-reaching influences of this territory .ind have assiduously culti- 
vated it ever since the epoch of Fraunhofer, who is justly regarded 
in his own land as the father of scientific industry in Germany. 
.Mready in the United States there are signs of an awakening to the 



needs of the situation. Under the auspices of the Optical Society of 
America a new s<ientific journal devoted exclusively to optical 
science in all its branches has recently made its appearance. This 
in itself isan achievement of igood omen. Undoubtedly, there is grow- 
ing up in this country a deeper appreciation of the desirability of 
closer co-ordination between science and industry. One of the lessons 
of the war— which would seem to be self-evident, but which needed 
to he driven home— is that the same science rules in the workshop as 
in the laboratory. This was the lesson that Fraunhofer taught his 
countrymen. Huxley said that what people call applied science is 
nothing but the application of pure science to particular problems. 

Animated by such purposes and ideals and by the example of 
England and France, a scheme is on foot to establish in at least 
■we of the large American universities courses of lectures and of 
laboi-atory training in the various branches of Applied Optics. It 
is proposed to include, for example, such studies as Geometrical and j 
Physical Optics, - Theory of Modern Optical Instruments, Lens I 
Design and I-iens Testing, Manufacture of Optical Glass, Refract- 
ometry, Polarimetry, Physiological Optics, Photometry and Illumi- 
nating Engineering, Interferometry, Spectrophotometry, Colori- 
metry, Oi)tometry, etc. A certain portion of this work is already 
being done in Columbia University, and it is to be hoped that the 
authorities of that institution can be induced to undertake the larger 
pi-ogramme indicated above. The graduate students would be 
recruited from \aiious classes — Army and Navy officers, students 
or ex-students of the universities and technical colleges, astrono- 
mers, manufacturers of optical instruments, oculists, optometrists, 
etc. The (n'dinary period of study would probably be one year. 
Presumably the courses could be so arranged that a student with 
the necessary qualificaitions could obtain the degree of Master of 
Arts. 

It is desirable to ascertain in advance whether there will be a 
sufficient demand for "optical engineering" in this country, 
because obviously this will be the first question that will be asked 
by a University Board of Trustees. The college authorities will 
wish to know how this project is viewed by the leaders of the 
optical industries themselves. It would seem that financial suppoi-t 
ought no"; to be lacking. 



exl)ibltion$> 

PHOTOGRAPHS BY MR. J. B. B. WELLINGTON AT 
HAMPSHIRE HOUSE. 
The Kammersmith Photographic Society is to be congratulated on 
having brought together a collection of the work, in pictorial photo- 
graphy, of Mr. Wellington, particularly as the prints upon the walls 
mark the progress of Mr. Wellington's aims from the early days of 
thirty years ago, when his metier was chiefly iinoaning eventides. 
to his most recent work in photography of the nude and by aj-tificial 
light. Although the chief business of ^Mr. Wellington's life is the 
technicalities of manufacturing dry-plates and printing papers, 
photograjjhy has always remained a hobby which he has cherished 
with all the ardour of the real amateur. We have been told that 
it is only one of other hobbies, among which are gardening, engrav- 
ing, cabinet-making, silversmith's work, and wood and metal turn- 
ing. Mr. Wellington is fortunate in findnig the opportunity for 
following these many crafts. His work as an amateur in photo- 
graphy has always had a strong a;ppeal to us for its " straightness. ' 
It invariably embodies the qualities of detail an,, tonality which ai'e 
the essential virtues of photography. In looking round an exhibition 
such as has been .brought together at Hampshire House, we are at 
a loss to know whidi we admire the most — the earlier landscapes 
in long, quiet lines, the later, more vigorous landscape work, done 
largely in the Highlands or the more recent studies of children 
gracefully posed in the nude. However, the visitor to Hampshire 
House can traverse all three periods, and, perhaps, come to a 
decision according to his personal inclinations. The exhibition will 
remain open for the next two or three weeks. 



Legal, Noticks. — A receiving order has been made on a creditors 
petition against Stanley Ford Chapman, photographer, Bel Air, 
Irnham Road, Minehead, Somerset. 



Fe)>ruar\- 1, 1918.) 



THE BRITISH JOURNAL OF PHOTOGR.\PHY. 



55 



Patent Reu)$« 






COMPLETE SPECIFICATIONS ACCEPTED. 
T^tae tptei/ieatitms are oUamabU. priet 6d. taeh, fost free, from 
Ihe Patent Ofite, »i, Southampton BuUdinga, Chancery Lane, 
LonJtm, W.C. 

The date m bracket* it that of application m thii country ; or 
abroad, im the oaw of falanU granted under the ItUemational 
Comeention. 

MvL-n-couKU.Corua ur Hlam.— No. 111,610 (April 12. 1917). The 
iiiveiitioa relate* tn thr ropyiit; uf coloured plaiw. drmwingn, 
etc., the object beJiig U> pnxlure aliarp aiid well defined repre- 
aenUliuiu of drawing*, tracing*, and the like in aeveral colour* 
at uiie uperatHin. 

In tlie w<41-kiiown proeew tanned " Ordorarax." by whit-h 
Ruod black-line printa are produced, a ferro-pruaaiate print is 
fir*t taken (rum the tracing, t)ii«, wbiUt uiKle«-elo|>ed, i* placed 
in ruiitact with a auitably pri>pBred gelatine surface. The 
uiidevekjped line* a4 the blue print exert a chemical reaction 
on the gelatine, ao that «uch line* take up grtntj ink (rom a 
pJler, wherra* the gnmnd remaina dear. From thi* *urfa<:e 
cnpie* in black line* on a white gnHwd can be pulled. A 
«Dloured ink can of cooiae be u*ed, bat the priota miut be in 
<ii>c colour only. Another method of working on the gelatine 
i* %Lt df»w tJ>« prigitial in " actince ink "— tiaU ia, an ink 
contaiuitif chemi<-aU which have an effect (qnal to that oT 
the iiriexpoeed iin<« of a blue print, which etche* tlir grlatine, 
nu photauraptlic exQpaur* bong neccaaary. 

then i* another | >ni c aai «n uae, known a* tlie " Hecto- 
grapii " pnxeaa. which cooaiata of writing an original (uanally 
*>f aaMU) dimanMOMl in aailina dye* of ao* or rariou* colour* ; 
whan dry thia copy i* placed on a aoitobly prefiarrd RrUtine 
aurface which aboortia a portion of the dye, and when clean 
paper i* rubbed down on thi* aurface, an imprnaian of liic draw- 
ing ia <J>(«ined. A numtirr of *uch i»|iiiawiina ean ha taken, 
but each become* <aint«r than the iMi owing to tlie exhauation 
of tha dye. Moreover, the i>utlini> can never he obtainrd in a good, 
ah-jrp, black line. ., ■ ■ f the coni|iu«ition and 

the iliftkulty of il dyt lari{e *ixe co|>ie* 

are aeM.n. taken, the prucciw tetiig itinhiird aknuat exci!w*ivety to 
hand akrl'hea and IMHMMcnpla. 

The <4>ject of the invention i* to ovarooMa tbaae (liflUultli-n 
by combtniog the two pruceeee* in Mich mnonar as to iilii,.;ii 
g<ioH prints in several colours, from a tracing which fni*in*rs 
a sharp well^leiined black or iuk>ur«l outline of the work being 
oipied, p ra daci d at ana operation, Ibaraby obviating the diffi- 
culty ariaiag fmoi (aahy ragiater, and in addition tha reatric- 
tiona aa regards dimension*, very Uiga printa, in ooa tbtet 
withoat joinla being easily printed. 

A W i W psdn l cMBpomd is prepared, which rmbodica tha eMcn- 
tial propartisa of i4m " Urdovrrax " and " Hectograph " oom- 
l — i l ioM heUm ralan a J to. A saiMbIa oompoaition for all 
pmceasas ia grfatina 20 parts, oatar CO parts, aad lerToiis 
Milphate 1 part, ao that tha linas of an exposed but undeveln|>ed 
blue |innt will exemse a cmtalytic action on the surface and 
cause printeia' ink to ailbfrv wherever the*e tinea have touched ; 
the ground re m a in i n g «k <f*e. In addition the colloidal cum- 
pound will abanrb inka of aniline dye, and will yield copir* by 
ptBMiiig daan papar upon such lUiaarbed dye. 

Having mn this colloidal (-iimiwaiid on ■ suitable surface 
Uiera i* piared theraoo an ex|>i>iMl bat undeveloped blue print 
taken fiMn the traeing to be cu|aad. On removal the linea 
an iakad np, ami tbaa upon the gelatine surface the work is 
eoionrad in wWabla aniline dyn. Tha bkck or coloured out- 
line fism tha origtanl drawing can be inked up for every im- 
, th* dlya will yirWl tlir colour without inking, umI a 
of good iia»aa>uiia arc eaaiigr nbtainad. 
an allai native, in some ca aaa the Una print can be 



coloured before being placed uii the gelatine, the colouring being 
transferred thence to Uie geUitd'Ue. Or the original may be 
drawn ia "actinic ink" and coloured before being placed on 
the gelatine, tlio coloitring beiTig similarly transferred to the 
gelatine. Or :in outline drawn in " actinic ink " can be placed 
on the gelatine ajid subsequently coloured thereon. Or the 
lines of an <ild blue print can be drawn over in •' actinic ink " 
and the print then placed on the gelatine, the colouring being 
eitiher placed on the print or direct on to the gelatine. All these 
vaciations are possible and requisite to suit special w.irk, but all 
embody the two processes which produce a print in sexeral colours 
by oiie operation at a fiiiction of the cost and in a fraction of the 
time of the pi-ocesses at present in use. 

In the event of a large number of copies being reijuiied, and 
to save further |>lioU>-printiiig or drawing, a pull in black line 
can be obtained rni paper, and whilst the luies aie moist they 
can be darted over wilJi "actinic transfer powder " — that is, a 
|)owder which lias the san.e effect as "actinic ink." Tliis |>aper 
co|)y il, thei. transferred ti) a new colloidal aurface, which it 
will etch ready for iiAiiig, and it oan either be cc)lour«d in 
an^ine before transfer, or the colloidal surface .subsequently 
ctiloured. — Benjamin .lames Hall, "Fieldend." Eastc-ote, 
.Middlesex. 



CraOt Rmms and IRarks. 

aVI'LICATIONS for KKGISTItATlOX. 

Hvnao.vix. No. 380,786. Photographic developers (chemical). White 
Band Manufacturing Co.. lad., 121, Seladon Road. .Smith Croydon, 
Surrey, manufacturing chemists. November 27, 1917. 

V. B. D. Plbx (Uesion). — No. 380,095. Photographic prints. Vin 
rent. Brooks, Day. and Son, Ltd.. 48, Parker Street, Kiiigsway, 
lynidon, \V.C.2, lithographers. October 10, 1917. 



MARKS PLACED ON THE ItEGlSTER. 
The folUitring viarkt tutue been placed on the register : — 
.Mthto. - .\o. 379.756. Chemical substances used in ' photography. 
Beniadette Chaloult Clement, 19, Sicilian Avenue, London, W.C.I, 
mauufacturing chemist. 



Jlnakcta* 



Exttact4 from our wctly and monthly conltmjmrariea. 



Davaloper for Bromides. 

ALTHoroH it is possible to reduce staining of the paper to a mini- 
mum (Writes -Mr. Oavid Ireland in the " Amateur Photographer " 
for January 281, bv the liberal use of preservative, the colour of the 
resulting printa is still a more or less cold black, so that no com- 
IM-iiMititHi is obtained for the extra trouble and the risk of spoiled 
iiisterial. 

Solium acetate, the writer finds, has the property of producing 
the exact tone he has had in view, and the formula given below pro- 
vides a dean-working developer, staining neither (laper nor fingers, 
the time recjuired for development being four to five minutes. 

.i^ium carbonate 220 grs. 

— «Sri*um sulphite 120 „ 

Sodium acetate 70 

Pota.isium bromide 5 

Acid sulphite solution 5 drs. 

Water 4 ore. 

To 4 drs. of this solution add 6 grs. dry pyro, and make up to 
Z o«. with water ; tap water is all that is required, the develojier 
having only a faint discolouration after use. and even this may be 
avoideid by the use of well-boiled water. (Jive the tray an occa- 
sional gentle rock ; do not agitate the ieveloper unnecessarily ; the 
image app<-ars In about one minute, and continues to gain in 
strength with great smoothness ; no loss of density occurs in the 
fixing bath, so that the print is removed as soon as the desired 



56 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[Jb'ebriiary 1, 1918. 



strength hus been reache.l ; wash a coujilc of minutes iii running 
water, and fi.x in : 

Hypo ... 2 ozs. 

Waier 10 ozs. 

Acid snlphite solution 5 oz. 

Presumably pyrogalHc acid in the form of ciystals will be employed . 
and 5 grain.« will be two lifts of a threepenny bit held edgewise 
between finjer and thnmb. 



meetings o( Societies. 



MEETINGS OP SOCIETIES FOE NEXT WEEK. 

Saturd.vy, PEmu'.\nv 2. 

StftlybridRe Photographic and Scientitio Society. " Amateur Photographer '' 

Prize Slides. 
Radlejr and District Photographic Society. Annual Exhibition and Social. 

Monday, Pebrkary 4. 

South London Photographic Society. ''Uoond the Mediterranean." Dr.CAtltin 

Swan P.R.P.S. 
Dewsborv Photographic Society. " Framing Pictures.'' F. Hojie. 
City of London and Cripplegate Photographic Society. "Mounting Prints and 

Passe Pavtout Framin«." N. P. Home. 
Bradford Photographic Society. Principles of Art .\pplied to Photography." 

A. Kei'ghley. 

Tuesday, Febritart 5. 

Koyal Photographic Society. " The Relations Between Optical Intensity and 

Quantity of Deposit in Prints." F. F Renwick. 
Birmingham Photographic Society. "Norway: a Peep at its Folks and Fiords." 

F. W. Pilditch. 
Hanley Photographic Society, Y.M.C.A. War on Land. National War Savings' 

Committee Lecture. 
SlieRield Photographic Society. Exhibition of Print.s by tlie Cardiff Photographic 

Society and Yorkshire I^hotographic Union. 
Keighley and District Photographic Association. Coffee Supper. 
Monklands Photoeraphio Society. Scottish Federation Prize Slides. 
Hackney Photographic Society. Slides by members. 

Wednesday, February 6. 

Croydon Camera Club. " Travelle.is' Samples gathered "by IMotor and Camera.'' 

P. Ackroyd. 
PiiotO'Micrographic Society. Member.s' Kvening. 
Edinburgh Photographic Society. "The Development of the Cinematocrapb." 

T. Haddow. . 

Thursday, February 7. 

Hull Photographic Society. Y.P.U. Slides. 

Huddersfield Naturalist and Photograp.iic Society. " Lantern Lecture." L. S. 

Cocking. 
Ijeigti Photographic Society. " .Amateur Photographer." Prize Drawing. 
Liverpool Amateur photographic Association. " Happy Japan.'' H.G.Allen. 
Hamuiersinith (Hampshire House) Photographic aociety. "Oil Printing and 

Transferring."' F. O. Coupland. 
Rolley and District Photographic Society, Members' Night. 



ROYAL PHOTOGRAPHIC SOCIETY. 

A L.\.NTERN leoture " In the Alps with a Camera " was to have been 
delivered on Tuet-day eveniing last by Dr. C. Atkin Swan. In con- 
sequence of tiie leotairer's sunmions at siliort notice to hospital duty 
in coimec'tion wiUi air-raids the meeting had to be abandimed. 



CROYDON CAMERA CLUB. 

Mr. W. H, I.Smith, technical manager of the works of the Platiiio- 
ty)>e Co., was announced to give "an exhaustive demonstration 
of .Satista printing paper, tut at the outset said he did not 
intend givin-g an exposition of stereotyped character, but proposed 
coating and drying a few pieces of paper, and making some prints 
by the aid of a half-watt lamp, which was much in evidence on 
the table. As usual, he was accompanied by his " beauty chorus," 
in the shape of gorgeous prints of extremely fair young ladies from 
negatives taken by foremost professional photographers. 

The.re ds no secret, he said, in the preparatioai of Satista pa;)er, a,s 
the process is patented, even if the same remark cannot be applied 
to the special methods employed in machine coating to ensure 
uniformity and fine-quality prints. The chemical reactions involved 
are very beautiful — more so, perhaps, than with platiiiotype, though 
those connected with palladiotype are e<iually interesting. As 
regards the last, another brand rendering a black image of platino- 
type quality and permanence will shortly be on the market. Some 
prints in the new ymper were much admired, and apjieared to be 
indistinguishable from platinotypes. 



A Satisti:. print, lu most are aware, bears an image of silver andl 
platinum, the high-light detail being composed of platinum, the 
shadows taking up more aiui more silver as their depth increases. 
By taking a sheet of ordinary P.O. P. .which has been kept away 
from white ligJtt, and immersing eH, in a solirtion, of salt to cmivert tlie 
"free silver" into chloride, after washing and drying it in yellow 
light, a slow gaslight paper is obtained, though an indifferent sub- 
stitute for the regular article. If such paper, or preferably a com- 
mercial gaslight paper, is coated with a solution of ferric oxalate,, 
then, after exposure to daylight or powerful artificial illuminant, 
it is feasible to develop it in the same way as a platinum print- 
namely, on a solution of potassium oxalate. Incidentally, a gas- 
light paper coated with potassium oxalate solution is converted into 
P.O. P., which, if kept fairly dry, will remain in good condition for 
years. In answer to a question, Mr. Smith said a, 10 per cent, 
solution will be about right, but in strictness this should b& 
adjusted to the silver present — rather an unknown quantity with 
gaslight papers. 

He then coated a piece of unprepared paper with a solution of 
fen'ic oxalate (exact strength immaterial for demonstration pur- 
fKises), to which l-50th grain of potassium chloroplatinite per ounce 
had been added. He rapidly dried the paper in front of a gas- 
stove, and exposed it behind a negative for 2ij minutes close under 
the 2,000 c,p. half-watt lamp. On development in a normal 
" platinotype " oxalate developer only a si:spicion of the shadows 
appeared. Omitting the platinum salt, he next repeated the fore- 
going procedure with a piece of paper coated with silver chloride- 
(previously coated and dried to save time). A gaslight paper will 
form a sufficiently satisfactory substitiite. Here, a full-strength 
picture finally resulted, quite good in its way, but the blacks were 
of brownish hue and the high-lights somewhat veiled and degraded. 
In the third experiment the same procedure was adopted as in the- 
second, except that this time the l-50th grain per ounce of the 
platinum salt was added to the sensitising solution. The blacks in 
the developed Satist.i (i-iuts were intense and of good quality, 
and the high-lights cleaned up without loss in modelling. Although 
the merest trace of platinum salt is required for the reaction, in/ 
practice sufficient is employed to ensure an absolutely permanent 
image, containing all details of the picture. 

It should not be overlooked that in the second experiment the 
high-lights were composed of silver, in the third experiment of 
silver and platinum, and in the commercial paper they w^ould be 
represented entirely by the rarer metal. This illustrates the com- 
plex way in which the platinum salt reacts on the silver salt and 
the silver salt on the platinum, possibly on the principle that "one 
good turn deserves another," though this scientific theory, in fair- 
ness, must not be attributed to Mr, Smith. 

The " spreader " used by him for distributing the sensitiser met 
with much approval, and, watching him, it appeared to be the 
simplest operation in the world to hand-coat paper evenly, always 
provided one is possessed ()f the sub-conscious knowledge born of 
practice, which in the present case can be loosely designated as 
"knack," The quickly-rnade substitute for a Blanchard brush is 
a. very simple affair. It consists of a piece of swa.nsdown about 
3 inches square, doubled over twice, and clipped in an ordinary 
penny letter-clip of the "bull-dog" type. A fresh surface after 
use can be obtained by folding the other way. The lecturer had 
e.xperienccxi aio trouble i.u account of the metal, as with swans- 
down any creeping-up action of the solution is of negligible quan- 
tity. A dozen or more .sheets may be coated before replacing the 
material. 

In the discussion, Mr. H. M. Bennett enquired if the paper used 
had a right and a wrong side. " Certainly," was the reply. 
"Which side do you coat?" continued the questioner. " Th» 
light side," said ilr. Smith, pleasantly, Mr. C. Welborne Piper 
suggested an osmium printiixg process on the lines of palladiotype, 
but, unfortunately, gave insufficient details to enable its manufac- 
ture to be undertaken •witli any certainty of suc('ess. On the co- 
operative principle the thing should go with a swing. " Every man 
his own Osmium," so to speak. A hearty vote of thanks was 
accorded Mr. Sm:t!i for an altogether excellent demonstration, one 
sufficiently novel to tickle the most jaded photographic appetite. 
Jaded appetites in other directions, by the way, are becoming some- 
what rare. 



Febriuiy 1. 19ia I 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



57 



nciDs ana notes. 



MessB^. J. H. Daixmkter, Ltd., of Church End Work*, Hi«h 
Rr>aii. Winesdmi, N.W.IO, advise iw that owini; to still furtiher 
advanrei :•■ the ooM of rmvr m-tterial and labour they are c»ni- 
lirlied to inrreaae Km lut price of their lenaea and aiiparatus a 
further 5 per cent., mdcing 20 per cent, in all, this advance to dat«' 
froir and incliKitn^ Febnu'y 1, 1918. 

The Lati .Mb. C. T. Chksterman. — We are sorrj- to see the note 
in " Process Work " of the death of an old reader and iHcaNional 
•correspondent of the " BJ.," Jlr. C. T. Chestennan. an Kiixlish 
Uthoxra|iher and process nuui, who reai-jed for over thirty yearn in 
Petiiii;rad, beinic emph yed in one of the (iovernmenl printing de- 
partment*. He waa a nian with an immense fund of useful infor- 
nuktton on all matter* concerning printing, en|raving, and process 
work. 

Skowdck Ward .Memobial Fvnd. — The London Hospital, White- 
chapel, reports with retard to thi* fund that the capital remains in 
the original se«-arities at £153. 

The accumulated income, including £7 Os. Sd., last year's divi- 
-dend, is now £S2 19t. So far there has been no call on Uieae funds, 
which are availaUe for oMttltinrt i„ any Httdg jjtotoijwiihfr who is 
an in or out patient of the hospital. Soch assistance may take any 
(••rm approved by the Lady Alminifm : the provision of nourishing 
food, support at convalescent homes, targical instruments, or money 
grants — assistance n«>t available fn»in the ordinary funds of the 
h<M|iital. The house goveritor of the boapital points out that the 
great development of photography in the Amy may well menu in 
the future that there will be cases needing aasistamp. when the 
fund would be of the greatest value. 

VtxoriUlD FBirroL. — ^The Vanguard -Maoulai tiiniig < ompauy, 
Miiideiihead. send us a i«mpte of tlieir abrasive paste iaued under 
the luuiie of " Krictol," and now put op in a somewhat more solid 
form, and in Hat tins, in which it can be handled without fear of 
Inkage. The preparation, as we have proved fur nunelves by a 
trial of it, prcaervea all the good quslitics of the original form. It 
:s an exceedingly aniDoth paate, with joat sufllicieut abraaive 
4]uality to frt it for the rafiid rubbing down ei dense patcbaa on 
nczatives and prints when apfilied with a bit of rag stretched over 
the fingertip, or, for finer work, over a blunt stylus. The abranive 
action is smooth and regular, and evidently the preparation is made 
with the utmost i-are frr the a\oif|itnce of particle* of grit which 
would ruin it for its s]iecial purposes. The shilling tin (post free. 
Is. 3d.) will last a phutographer for yean in the t.eatro«ot of con- 
siderable^ numbers of negatives or prints, and on occasion may be 
usefully pressed into service for removinf tarnish from such surfaces 
of mtUl which do not yield quickly to the ordinary liquid metal 
polishaa. 

PHOTonBArHs roB BiRMiKOHAM War MvHrM.— The Photo- 
graphic ilttb' Committee of the Birmingham War Moaeum movement 
are aniinus to get into immediate t<>uch with all phatofrapben (pro- 
fesswinal and amateur) who poasenn negative* illustrating the great 
part the city has played in the war, with the object of obtaining a 
permanent collection of printa fur pmartatinn as a record and 
■Maaolo lor future reference and study. The collection of 
print* will be mounted, arranged, and catak>goed by the 
sab-commitlae on the Jines followed ao ■occcatfully hy the 
WarwiekAir* Sarraj. The pnnU ahonld be made by some 
permanent proce aa (earbon, platinotype, bromide, preferably toned). 
In cases 'where phoiofimphan are unahl* to supply prints the nega- 
tivea may b* lent, or wOl be accepted •■ a gift. A full deacription 
of the v^ctam ahonld be sent, with th« names of any prominent 
r>«nMM appearing in the scenes depicted. The photographs re- 
qnirad to render the collertion complete will necesaarily rover a 
wide are*, and will include w.>rk in munition factories, women's 
work in the war. as well as eiit<TtainmenU for the wounded. Lists 
and all communications should )>r sent t» the hon. secretary, .Mr. 
<iaor|* WhHehooa*, PhotogrBphic Sob-C<jmmittee, War Memorul 
Maaenm, Art Onllny, Birmingham. 



Gaslii;ht Printimc; fbo.m Amateurs' Xeg.^tives.— In making up 
the artiol.- by .Mr. D. Charles last. week for the press, the inclusion 
of an additional drawing (fig. 4) of the e.xtemporised printing frame 




for gaslight printing was. by an oveisiijht. .ivtrlu„ked. The plan 
representation of the frame is now here printed, and will serve to 
supplement the deUils of coiutruction given bv .Mr. Charles on 
p. 43 of th« •• B.J. " of January 25. 

Bbomide Paper is .\-Ray Work.— A contributor to the "Photo 
Revue." M. K. JavHui{ues. describing liimseif as a military r.ndio- 
grapher, states that, on account of the itreatly increased cost of 
plates, teats have been made of Ahe |H)sgibility of using the ordinary 
bromide papers in .Xray work, and that verj- good results are being 
"liUined by direit ex|>o«ure to the .\-raya. It is stated that with 
plates and papers lieo:ing einnlsion of the same rapidity, papers 
require an e.V|>o«ure of from one third to oiie-(|uarter in order to 
yield a strong negative image by reflected light. The Lumifere C. 
paper regularly used by the French Public Health Department 
requires fifteen times the exposure of the Lumieie C. plates, but by 
means of the new Cupluiii screen (his time of e.\|K>sure can be reduced 
to one-twentieth. In the case of tlie Luiniore C.R.. L.R., and E.R., 
rapid bromide papers as supplied for enlarging, excellent results 
have been obuined with exposures .ippro.xi^alely the same as 
tliose for X-ray plates. tJood results have also been ubtnined with 
-Msio paper at expoautes of about half, a second. The 
foregoing papers have not been found suitable for the 
making of positive prints from the negatives obtained on them, but 
with the negative pafwr of CSuillemiiiot oithei- jHisitive or negative 
I'rints can be made with exposures ab<mt one-third those of the 
Lumi^re X-ray plates or .\-my negatives produced at about the 
same exposure. From sm-h negatives positive prints may be taken 
or the negatives themselves examined by transmitted light. It is 
found practicable, according to the character of the emulsion, and 
the time of exptisure, to obtain hardness or softness in the resurts, 
and at the same time a rendering «if detail and range of tones 
which, while not e<|ual to the results on plates, are sufficient in a 
large majority of cases. 

SuTLKA IS .SfLPHloe Tosi.NO.— A short time ago we made refer- 
ence to the vahuble properties of Serteka when used with amidol. 
which it transforms, in some apparently magical fashion, into a de- 
jr^loW with great lasting properties. The maker, .Mr. G. W. .Sccie- 
'tini;;'jOirtlO», Tufnell Park Road, London, \.7, has now issued a fre.sh 
circular in which he draws attention to the properties of .Serteka 
when used in the sulphide-toning process. We have before pointed 
out that bromides developed with amidol and Serteka give very ex- 
cellent tones, but the new instructions prescribe adding Serteka to 
the bleacher, and to the sulphide bath, as well as to tile developer. 
We are told to add thirty dnips of Serteka to 10 oKs. of bleacher, and 
1 dram to 10 ozs. of sulphide bath. We used thirty drops in the one 
case and sixty in the other, and tested the effect. The result was a 
slightly lighter and warmer brown than that produced by toning 
without Serteka. On further trial we foiJoJ that the effect seemed 
t<i be produced entirely by the Serteka in the eiilyhide, and we could 
not detect any difference as the result of addi.i^ ff to the bleacher, 



58 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[February 1, 1918. 



whicli was tlie usual one of fcrricyaiiide and bromide. Ajipareiitly 
the instructions might be simplified in this ro.»pecl. The change in 
tone..! is a distinct one, but it so liappened thai the prints used gave 
an exceedingly fine tone without Serteka, so that the new tone was 
hardly an improvement. Tone is, however, more or less a matter 
of taste, and Serteka would no doubt effect a great improvement in 
the case of prints tending to give too cold a tone, while it should also 
have uses in the case of heavy prints that require lightening. Ono 
claim of the maker is that it gives pure whites. The whites were not 
stained in our prints, though no pure white existed ; therefore we 
could not lest its effects as regards stained whites. We can, in fact, 
detect no cliange in the whites, though the colour generally has 
changed very distinctly. 

U.S. Anti-Trust Actions Postponed. — Messages from Washing- 
ton to the " Rochester Herald " of January 3 report that Federal 
suite to dissolve seven so-called "trusts " have been postponed, at 
the solicitation of the United States Government. The Govern- 
ment gave as its reason that the dissolutions would require financial 
operations on a large scale if they are to be genuine and effective, 
and that Secretary of the Treasury McAdoo had asked that all 
money for new cajiital be left available to the nation. 

Suits against tho Eastman Kodak Company and five other cor- 
porations are all postponed until at least October next, the begin- 
ning of the next term of the Supreme Court. 

The brief sent up by the Solicitor-General contains the reasons 
for the postponement in terse language. It follows : 

"In order that the Government in this time of stress may not 
meet with competition from private enterprises in its financial 
operation.s and the flotation of its loans, the Treasury Department 
has been constrained to urge that all private financing on a large 
scale shall be avoided as far as possible. Thus, in his annual report 
on the finances for the fiscal year ending June 30, 1917, the Secretary 
of the Treasiu-y makes the following observation : — 

" ' The Government must, if necessai'y, absorb the supply of new- 
capital available for investment in the United States during the 
period of the war. This, in turn, makes it essential that unneces- 
sary capital expenditures .should be avoided in public and private 
enterprises.' 

" It is quite clear that the dissolutions wliich are sought in the 
pending cases will require financial operations on a large scale if 
they are to be genuine and effective. Important as the remedy 
sought in these casee is believed to be, it must-give place for the 
moment to the paramount needs of tlie hour." 

The suit against the Eastman Kodak Company (adds the 
" Rochester Herald ") is before the Supreme Court on an appeal 
by the defendants. The case is of long standing, having been 
instigated by Attorney-General Wickersham during the Taft 
Administration. When Mr. Wickersham's term of office had 
expire.! he had practically consented tn a withdrawal of the suit 
after the co7npany had agreed to alter certain selling practices which 
were alleged to be in violation of the Sherman Anti-Trust Law. 
When Attorney-General McReynolds, of the Wilson Administra- 
tion, came into office he revived the suit, and it was brought to 
trial in Rochester and Buffalo before Judge John R. Hazel, who 
lianded down a decision requiring Government and Eastman attor- 
neys to devise a plan of reorganisation that would be acceptable to 
the Court. The attorneys failed to agree upon snch a plan, and the 
defcniant appealed to the Snpreme Court. 



FORTHCOMING EXHIBITIONS. 

February 2 to 9.— South Glasgow Camera Club. Secretary, John 
Baird, 164, King's Park Road, Cathcart, Glasgow. 

February 9 to 16.— Glasgow and West of Scotland Amateur Photo- 
graphic Association. Secretary, G. S. McVean, 125, West 
Regent Street, Glasgow. 

February 21 to 23.— Leicester and Leicestershire Photographic 
Society. Sec., H. C. Cross, 80, Harrow Road, Leicester. 



Correspondence. 



Correspondents should never write on both sides of the paper. No 
notice is taken of cotnmunications unless the names and addresses 
of t}ie writers are given. 

We do not undertake responsibility for tlie opinions expressed by 
our correspmdents. 



AIR-BELLS IN TANK DEVELOPMENT. 

To the Editors. 

Gentlemen, — In last week's "B.J.," in your answers to cor- 
respondents, we notice an inquiry by " M. B." as to the cause of 
air-bells adhering to plates v\'1ien developed in tanks. As we have 
had a lot of practical experience with large batches of plates during 
several yea.rs, may we suggret two causes rA this trouible which are 
often overlooked. One is that some makes of very rapid plates 
have a rough surface, which easily carries air down into the solution. 
J'his may be overcome by passing the rack oi pJates quickly under 
the tap ibefore putting them in tank, holding the rack at an angle 
to allow the water access to the surface of every plate. 

Another, and viore common cause, is bubbles on the surface of 
solution before putting rack of plates in tank. This is not often 
noticed in the dark room, especially in a deep, narrow tank, perhaps 
only two-thirds full. These are caused by hot and cold water from taps 
being iim into developer. Also more often hy stirring it up at last 
minute with thermometer or other article. 

If any bubbles are on the surface, they must stick to plates, no 
matter how carefully ])ut in. If none are there, and the plate-s 
lowered slowly, there will be none on plates. 

We always draw a wide (width of tank) piece of cardboard across 
the surface before putting plates in, and this always prevents this 
trouble. — Yours truly. 

Eagle Tank Co. 

15b, Cank Street, Leicester. 



ANASTIGMATS AND OTHER LENSES. 
To the Editors. 

Gentlemen, — I am glad to see the article by Mr. Graham Nicol on 
the covering power of lenses, although it emphasises truths that need 
to be brought home to a large body of amateurs rather than to pro- 
fessional photographers, who are not apt to swallow evei"}' claim 
made in a manufacturer's catalogue. While no ambitious amateur 
who can afford the purchase can abstain from the possession of an 
anastigmat, it is safe to say that for 90 per cent, of the work that 
the amateur will do a rapid rectilinear lens will be equally effective, 
while the quality of the negatives obtained with the older pattern 
will be better, because of the smaller amount of stray light inside 
the camera. When one comes to anastigmats with four and five 
separate glasses, tihe rapid rectilinear will win every time, even in 
tlifc matter of rapidity at the same aperture. There I speak from 
bitter personal experience. 

The R.R. has been brought into some disrepute from the fact that 
in later days it was manufactured, or rather put together, from 
lenses ground in numbers at the same time, and was sold at a price 
which did not allow for those niceties of construction which cost so 
much, and mean so mugh in ultimate performance. The perform- 
ance of such lenses was inevitably inferior. To know what a rapid 
rectilinear iens is capable of one must poss^ess an instrument such as 
vvtu- mad(' by Da.llnieyer, R-)<s, or Gn;'',b — the Litter a name scarcely 
known to the present generation of photographers, but the maker ii» 
his day of some of the finest optical instruments that ever left a 
workshop. Such lenses will run even good modern anastigmats hard 
in the matter of definition to the edges of the plates which they are 
calculated to cover. 

Anastigmatism as a projierty in a lens is in danger of being 
exalted into a fetish. As a fact, the virtues of the modern lens only 
become conspicuous, as a rule, outside the limits of the plate for 
which they are listed. The use of an anaatigmat gives, in most. 



Kwruarv 1, 19ia] 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



59 



csM*. a reserve power fur which much has to be sacrificed, just a« 
the high-speed focal-plaiie shutter, which inay be used for one 
e^poaare out of twenty, handicaps its gioMeasor for slow »|>ee.l work. 
.Vly own batter>' of lenses for a hand camera includes the most (ler- 
feet of the Lie. man anastiKmats. a much cheaper English anastigmat, 
a rapid rectilinear, and an excellent single lens. I find tiiat at / 8, 

hich is ordinarily the largest aperture it is safe to use.having regard 

• depth of focus and the uncertainty of judging distances, there is 
nothing to choose in deftnition bet«feii the first three leuse«, while 
at fill the single lens begins to challenge all its competitorts. and 
yields negatives unrivalled for brilliance. 

When one passee to larger plates, the superiority of the anastigmat. 

.hato\'er it be, diminisbea rapidly, until one is inclined to say tliat 
;he man who is working whole plates or be>on.l. and purchase* the 
' iionnously nwtly anastigmata fr>r such sixes, has more money than 
>>it. — lam, etc., .VimtnH \V>ts<i\ 

26, Morpeth Mansions. We*tmiii.<>t< 



A.MERICANS AND BRITISH COPYRIGHT. 
To the £dit<jn. 

G<-ntleinrM. — In your article on copyright in this weeks is«ue you 
make the statement that Americans may obtain copyright in Great 
Britain without the observance of any formalities. You are in error, 
as are also thiise eminent writers whom you cite as supporting your 
Ml'- It in |Kjasible that the*e writer* may have expreased their 
opiiiiuM before the issue of t)ie Order in Council rvlating to the 
I i:it>-d States, but even then there was Mflicient indication in' the 
liriti.«h Act to make tbcm pauae befor« ezprening such a view. 
Thus, the Art aa paaacd contains a provision that Orders in 

' il may provide that the terms of copyright shall not exce«d 

>nferre.l by the country of oriein of the work. This was not 

,..) ... .1.,. original Act, hut was introduced in its progreas 

•-nt. It emlxtdiea a prinripl* which wsa hinted at 

r^f t. and shows that the Legislature did not contem- 

foreigner in any more favourable jioaition regarding 

i>:ii-r, ' .'wi.'ht than British subject* were placed in with 

rrk'nril t.> < ")>> nt(ht in that foreign couutiy. This principle is also 

< ' ! !' Ihi- provision, which apf>eared in the original Bill, that 

I in Coum-il may pmvide that the enjoymrnt of the right.) 

r>-<i hy this Act shall be subjnt to the aocooipliahment of such 

I'lns an 1 formalities lit any I aji raajr be prMcribed by the 

'A cautious writer would, tbervforc. have ezpreaacd doubt 

^•' had •een the Order. 

■ Ort/ff in C'lwa. ' ' ' "< copyright with the I'uitad States, 

I Frhmnr^ 3. \u settle* the poinL This Order was 

> .\iiiFrii-»n Act of 19QB not having made 

" mei'hanical rights ". created by the 

Hr.tiiih Art ..( lail. 

This Order provide*, inltr alut, " that the enjoyment of the righia 

'■ fred by thi- ' • . the accomplishment of the 

'.iiiiM and '. the law of the I'nited 

*. " 

I. therefor*, that Americaas, to obtain copyright in 
>•< r<..vt>-r at Washington, by the deposit, in the 
.-::•<! .1 rk, of •■ one cnpy of a ponilivr print of the 
.<c>rx." ur, Hi the case of puhlished printa wit^' ' ,-ht notice 

iii« riHH hy the depiisit " prrimptly " after pul. ■ two com- 

of the work. These formalitias you tlescribe in your 
' your American readers will ttr from the foregoing that 
ol tham is necessary to obtain copyright in 
.shich the work falls into the public domain. 
'I not particularly interested in photographic copy- 
• dt-mands a fairly close acqnaintanceahip with both 
'lal copyright, and — your article may have 
reader* I thought it better to paas on this 
tion.— I mnain, yours truly, RoacBT Waixaix, 

, Hon. Sei-retary Scottish Photo- Pictorial Circle. 

514, Paisley Road, Glaagow. 

'WV are obliged to Mr. Wallace for hia letter. In order that the 
may neciva tha aaioa degree of prominence in our pages aa 
"'laadiag articta of laat week, we refer t<> it in a paragraph 
nder Ex C a U wdwi.— Ent. " B.J.") 



ilnsiDers to CorresponaentSa 

— • — 

8PBCIAL NOTICB. 
/a aoiMt^nange of ftntral rtdueed mppliu of paper, at tkt rufilt 
of prokibi lioK of lAe importatio n of much wmd pulp and groii 
B tm ailer ipate iMl b e avaUable until fwrthtr noUtt for rtplitt 
to torrttpondentl. 

Moreover, w* triU annoer if post if itamptd and addruted enve 
lope it tnrloe ed for replfi 6-eent International epupon, fro m 
readert abroad. 

rke ftM fmestiont and antuieri %rill be printed onlf in the tote of 
inywriw of gener al intereit. 

Queriet to be anneertd in tAe Fridaf't " Jommal " mutt reach ut 
nM lat er than Tuttda f {p ot ted Mondaf), and ihould bt 
addrttted to the Sditort. 

A. C. Faib — In order to get, by eaay reading, a wide genera' 
ac()iiaii>tAncfi with all photugra)>hic proceseea, tbooe of the present 
and tho ch.ti <ait» o( th? iiaist and of the prinoiplea of lenses, there ■ 
is no book to equal Mr. ChnpoMui Jones's " Pliotograpfhy of To- 
day," which our publishers supply for 68. 5d. post free. Yes, it 
deals also with ooknir photography and pho>to-eiitgraving. 

RrrA. — Potassium penninganate is very scarce now and correspond- 
ingly dear, but we should certainly think you could buy a small 
(|uantity from lar>:e dealers in chemicals such as Messrs. Johnson ' 
and Sons, 23, Cms* Stret-l. Fiiisbury, E.C. 

A. H. — Quite true that it is no use running half-watte on a lower 
voltage, but we should say that a 230 v. current for 200 v. lumpe 
is too much electric pressure. You would get a fine light, but 
you would cut down the life of the lamps to a good deal aliort 
of their scheduled thousand hours. We do not think for n 
minute that it would pay you to use these same lumps at the 
higher voltage .' 

H. K. A. — There is not. to our knowledge, any tank on the market 
for developing a small number of film spools. I'sually dealeis and 
photographers who go in for this branch of work get made for 
them a wooden tank of depth to take the lengths oi spool with 
which they are dealing, and of breatlth and width to accommodate 
the quantity they want. We should say that your only alternative - 
to the Kodak outfit is to get a tank made for you. 

R. E. — We think that vnu will find four 1,000 c.p. lamps sufficient. 
If you place one 8 ft. fmm the ground, 8 ft. from the background 
opiKMite the centre, and the other three in a curve coming round to • 
within 5 ft. of background, you will be able to get all ordinary 
liifhtir^a. Il is a good plan to have one lamp on a ftiindard, say, 
the one nearest the background, so that it can be shifted for groups 
of fancy lighting. Cheap white calico is the best diffuser. 

P T. -Over-develojied prints are beat treated in a weak iodine- 
cyanide reducer made from 7a) 10 per cent, solution of iodine in 
potas^ iodide, and (b) 10 per cent, potass, cyanide solution. 

(a) 30 minims 2 c.c.s. 

P>) 10 minims 0.6 c.c. 

Water, 2 o» 60 c.c.s. 

.Adding more of (a) and (bl if neceasary. 

P. Cf. L. — The (joldtoned sepia printa ought not to develop blue ■ 
patches. These certainly point to carelessness in manipulation. 
On the other han.l, our experience is that the warm red chalk tones' 
are not exceedingly permanent. Tests which have been made by 
exposing such print;> with one-half covered by black |>apcr have 
shown that the ex|H>sed part gradually underwent slight change 
of colour in the light. We should say that the tone is not nearly 



60 



THE BRITISH JOURNAL OF PHOTOGRAPKY. 



f?ooni3iy 1. 1918. 



so pcriniiieiil n- the ordinary sppia tone, and, in fact, is probably 
a little less |)cniianent than that of an ordinary black-and-white 
print. 

T. R. W. A. — 1. I'he ordinary upright mantle is not the most suit- 
able. A good inverted patteiii is better, and none better than the 
" Howellite " burner, which you can buy for a shilling or two from 
Messrs. (JriflTias. Kingsway. and which is very much superior to 
the ordinary burnei-s of this tyi)e sold by gasfitters. 2. Usually 
ground glass of ordinary thickness, such as is used for focussing 
screens, is quite sufficient. It should be as near to the mantle as 
it can be without risk of breaking. 3. The only suitable type of 
metallic-filament lamp for enlarging is the focus pattern— i.e., with 
the filaments brought together in a small bunch, but these are for 
the time being not obtainable. 

S. Bros. — As regards the bluisb stains, it is pretty certain that 
they arise througJi insufficient fixation. Prints now require 
more thorough fixation than when made on pre-war paper. We 
have advised many people who have been troubled with these 
bluish stains, and they found when they made it a practice to 
pass prints through two fixing baths in succession that they ceased 
to get the stains. We know one firm who now makes it a rule 
to pass all prints through three fixing baths, although v,-e do not 
think the third is necessary. As regards the yellowish spots, it 
is more difficult to say, but we think a cause may be overcrowd- 
ing of prints in the fixing batih, whereby minute air-bells stick 
to them, with the result that fixing is not complete. 

J. W. H. — About the best little book you can get on the principles 
of colour photography is No. 128 of the " Photo-Miniature " series, 
" All about Colour Photography." No. 147 of the " Photo-Minia- 
ture " is a practical handbook on the Autochrone process. Neither 
of these is obtainable from the publishers in New York nor 
from English agents here, but we should say you could most likely 
get them from photographic dealers in Manchester or Liverpool 
such a* t'hapman (Albert Square), or F. V. A, Lloyd (15, Lord 
Street, Liverpool), who usually order each number of the " P.M.," 
and very likely have one of these issues still in stock. The only 
two other books are " Colour Photography," by Dr. Lindsay John- 
son, which our publishers can supply, price 4s. lid., post free, and 
" Photography in Natural Colours," by Dr. E. Konig, translated 
by E. J. Wall, obtainable price 2s. 9d. 

J. E. Pout. — The best book on making of half-tone blocks is " The 
Half-Tone (Process," by J. Verfasser (Iliffe and Co.), price 
7s. 6a It is utterly useless for you to think of buying the appa- 
ratus and Materials which are necessary for half-tone block-making 
iraless you can see a sufficient demand for it, which will keep the 
whole equipment in constant working, and which will emi^loy two 
or more i-eople regularly on the work. We should say, at a mode- 
rate figure, the equipment would cost something like a hundred 
I)Ound-i. L'nlcss your customers want blocks in a tremendous hurry 
we should have thought that you could have satisfied your require- 
ments by passing on the work to some photo-engraver. Even in 
these times it is, we find, not by any means difficult to get half- 
tone blocks delivered within twenty-four or forty-eight hours of 
delivering the original to the engraver. 

C H. C. — Evidently there is some iron somewhere in the solution 
you applied to the prints before you treated them with the ferri- 
eyanide and hypo reducer. The most probable source is the 
alum which freciuently contains iron and would have the effect 
which the print shows, although we cannot remember having ever 
seen such a strong blue stain produced in this way. We should 
say the best remedy you can now apply to the enlargements is 
to soak them in a solution of oxalate of pctasih of strength 75 grains 
in 1 oz. of water. Try this on some cotton wool on a spare print 
to see whether it will work. The best way to reduce a sulphide- 
toned print is to immerse for a time in a solution of bichromate 
of potash about 100 grains, water 10 ozs., with addition of about 
1 oz. of strong hydrochloric or strong sulphuric acid, but these 
processes are not by any means certain. 

L, K.— -You can make up the developer for the Uford plates from 
dry chemicals by dissolving in 5 ozs. of water 10 to 20 grains of 
pyro, 110 grains of sulphite, 110 grains of carbonate, and 2i grains 
of bromide. These are the cryst. form of sulphite and carbonate. 



If you want to make up the solution <iuickly it will be better to 
i:se the dry. or anhydrous, forms, taking in this case 55 grains of 
sulphite and 45 grains of carbonate. As regards the bromide, the 
best plan is to keep it in a 10 per cent, solution, adding 25 minimB 
for the 2_y grains. -Making the developer up in this way will be a 
long job if you need to weigh the chemicals. Your best plan 
M'ould be to get a few narrow glass tubes, such as the " tabloid " 
chemicals are sold in, and mark them, so as tp represent the bulk 
of the quantity of sulphit-e or carbonate you require. For the 
pyro, if of the light sublimed form, you had better find some kind 
of spoon which will just hold the weight required. 

W. A. — 1. We are sorry we do not know any other stuff here or likely 
to be obtainable in Pai'is as a substitute for Ruberoid. There is 
what is called asbestos board, but it is rather ten.ier and brittle, 
and while it might do for the bottoms of dishes or sinks (the sides 
being made of stout wood), we are quite sure it cannot be handled 
in the way that Ruberoid can. You could get material of this kind 
from dealers in builders' requisites. Failing that, we should say 
the only thing is to have dishes made with hard wood provided 
with a groove, in which you can fit glass for the bottom. 2. 
Hardly practicable to use gutta percha by itself ; it is too slow 
and time-wasting a job. The usual plan is to mix the gutta percha 
to a solution or a paste by digesting it in the' heat by turpentine, 
or, if you cannot get that, in the cold by carbon bisulphide. You 
can add some asphaltum, which will iniprove the watei-proof 
quality of the coating and at the same time make it harder. A 
mixture of this kind is largely used for waterjiroofiing wooden 
surfaces. We do not recall the suggestion to coat with tar. Pre- 
sumably it would only be possible on the outside of wooden 
washers. 3. Without knowing exactly how the carbons of the arc 
stand in relation to the screen, we should say that angling the 
screen more under the lamp would make very little difference to 
the illumination of the sitter. It amounts to this — that the sur- 
face of the screen is your source of light for the sitter, and the 
chief part of the source is that immediately facing the lamp. 
You do not alter this very much by angling the screen. It 
seems Ui us the only effect would be to reduce somewhat the 
strength of the light thrown off by the lower i>art of the .-screen. 



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IMPORTANT NOTICE TO READERS.— Until fwrtlwr notice 
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THE BRITISH 



JOUMAL OF PIOTOGEAPHT. 



No. 3014. Vol. LXV. 



FRIDAY, FEBRUARY 8, 1918. 



Pbice Twopence. 



Contents* 



Wbat io 



El Catus«a 

Tmr Uira acucrrr 

DO Abol-t It 

Co«T 4JID PmoDccrr .....«, 

Hi iraririoDanavixOmCALPiw- 

'fL-Tion.— IL By J. A. Orui(* 
Tat "KtcMn " L.ntB— Homc Msw 

r*<.-n un> Bxmuaiim. B; 

A. LockMI 

A*.i.r*irr.' Mane* .••.. 



U 






65 



tkot 
Patiiit NB<n U 

AmuctA C9 

Foaiaoaana Essibttioiii tt 

M nmna e* au au ti m ID 

Nb»* tmo Narr« . TO 
CoKmsooasuics ; - 
D« n l» j ir pQtaooiaa — A New 

Pawn tat Dmttmi Bill ... 71 

n 



TKt Summary of coNl«nt« whtch unaU]/ oeettptM (k« iotoir half 
of (Au coJimm viii bo fotmd >-' "'" '<"( of tho pago ovorUetf and 
tfitt ednimuo to bo plaeod Ihtrt u ,-guUtr poiitum u roquirod 

for motieoo rolatiHf Io Urn ferlkeomjjuj ' "-•^■•■," 



Th« Day B«for« Yesterday. 

Wednzbdat — " the laat aa ever was " — February 6 — the 
day before yesterday — was, as it finally turned out, the 



te waa placed on sale 

By the ezigendee of 

•n this day. We 

:i of the Almanac 



day on which the 1918 
throughout the United K 
newspaper production we ar 
are happy to know that the 
IS an accomplished fact. 

We congratulate ourselves that d«epit« the difficulties 

of the times, the 1918 Aim- '3 appearance 

almost at the time announce<l . *nd scarcely 

>n the first Almanac ir, that of 1915, 

im alio the first to ma: : .insference of pub- 

.' iiion from before Christmas to early in the New Year. 

rii:- New Year time of publication was decided in 

I'U, very soon after the outbreak of war. We are not at 

satisfied that it can be continued in normal times, but 

' '' and many other things most await the new and 

h.<|>pier days to come. 

At any cate, we need not nov inflict upon the good 
reader any discussion of the pros and cons of publisning 
l)efore or after CThristma."!. !>«•» it be now our object to 
pT'idaim the ■" ■ throiit,'hout the length aqd breadth 

of these iaiai. la to -ov wherever ordinary photo- 

L-raphic requi^iies are p 1p, the Almanac can 

now be bought. No don ''■Qg the two days on 

whirh it has been on sale the stocks of dealers have 

« have intimated in pre- 

' n 1918 Almanac, more 

predecessors, baa been 

the basis of individual 

liie proportion of copi* 



already been drawn upon. 

vi'im iri'tii'ments of these ■ 

' '■ • '! ■^'' ..!!.»r of its fit 

'Utors atr 

. -ill. Jim j>in> 0<^1 with til 



red with a view to rhaii.<> sales has probably never 



lower. On which 
'< requiring the new 

''living it. 



it is neceaaary that 
lould lose no time in 



EX-CATHEDRA. 

Lens Lore In spite of the efforts of the photo- 

S*** , ■ , graphic Press and sundry lecturers, the 
Professionals, knowledge of lenses in general is a 
sealed book to the majority of professional photographers. 
Many have no idea of any system of diaphragm num- 
bering, and in one case within our knowledge one of our 
leading portraitists did not know the meaning of achro- 
matism, that is to say, that an image could be sharply 
fooussed and the exposure yield a fuzzy negative. In 
practice the want of this elementary knowledge often 
means serious pecuniary loss, as unsuitable lenses may b? 
purchased at nigh prices, and lenses already on hard 
may not be utilised to their full capacity. The principal 
points on which the unscientific lens user should seek 
information are briefly as follow : a thorough knowledge 
of the values of his lenses, giving a clear idea of their 
relative rapidities at full aperture, with the ratio of 
exposures when using the single components; what " dis- 
tortion " really means, the " depth of field " obtainable at 
a given aperture with various focal lengths; the means 
of controlling sharpness of definition ; the meaning of 
spherical aberration as contrasted with curvature of 
field, achromatism, and the properties of non-achromatic 
lenses, and particularly the care of lenses. This latter is 
an important item, as many good lenses are put out of 
order, and sometimes permanently ruined, by careless 
handling ; thus, dropping a lens may not break the 
glasses, but it may disturb the centering and impair the 
definition; careless cleaning may partially depolish the 
surfaces, causing dull and foggy images, while damp 
will corrode the surfaces, causing what opticians call 
rust. On the other hand, such defects as bubbles in the 
glass, slight scratches, and even small chips, which 
alarm the uninitiated, should be estimated at their true 
value, as these cause little harm in working. All this 
information is to be found in any good elementary work 
on photography, and bears the same relation to scientific 
optics that a cookery book does to a treatise on dietetics. 
» » « 

Plate Sizes. We note that the Kodak Com- 

pany have introduced a new plate 
sise to the American public in place of the 10 
X 8 which is so popular there. Most people 
have regarded this as too square, as, indeed, are 
most of our plate sizes. The new size is 11 x 7, giving 
the same proportions as a postcard, which is exactly half 
these measurements. As far as cost is concerned, a 10 x 
8 plate has an area of 80 square inches, while 11 x 7 
only 77, so that the price need not be different, while 
a much more acceptable picture should be obtained. For 
a long time many photographers have used 12 x 8 plates 
for panel portraits, groups, and sometimes for landscapes, 



62 



THE BRITISH JOURNAL OF PHOTOaRAPHT. 



[Februaiy 8, 1918. 



thus effecting a saving of 20 per cent, as .compared with 
a 12 X 10. Of course, a 12 x 10 camera would have to 
be used until our makers see their way to make 11 x 7 
cameras. Our American brethren seem to have a pen- 
chant for narrow pictures. Here it is rather remark- 
able that so pleasing a size as 7J x 5 should have been 
allowed to fall into desuetude, but probably it is due 
to the difficulty of obtaining fresh plates of these dimen- 
sions, except by specially ordering them. It is an excel- 
lent portrait shape and is equally pleasing for landscapes. 
The two sizes, 11x7 and 7^ x 5 might well replace the 
10 X 8 and 6| x 4| for much professional work, and a 
better price could be obtained with little additional 
expense to the photographer. 

* » » 

Ppints Whjle there is no likelihood of such an 

without absolute shortage of hyposulphite as 

Hypo. would compel alternative methods of 

printing to be adopted, perhaps those of an experimental 
turn of mind may like to exercise their ingenuity in 
devi.iiug meanj by which the prin's on bromide or gas- 
light papers could be produced in permanent form without 
the use of hypo. At present there is no method of this 
kind which would satisfy the present commercial condi- 
tions. But if cpnditions were altogether upset by a 
phenomenal scarcity of hypo it would probably not be 
beyond the capacity of our photographic experimenters 
to devise a method by which the residual unaffected 
silver bromide could be removed by means other than 
solution in hypo. One hint of such a process is contained 
in the reversing procedure which is employed with the 
Autochrome plate. In its applicatipn to prints it would,' 
of course, be necessary to print from a positive instead of 
a negative, then dissolving out the developed negative 
im&ge with a solvent cf metaluj silver, and obtaining the 
positive by re-development of the residual silver bromide. 



Hypo 
Recovery 



No doubt the cheapness of hypo in the 
past has been the cause of the absence 
of any investigation of its regeneration from fixing-baths 
at the same time that the dissolved silver is recovered. 
A violent disturbance of prices might lead to some con- 
sideration of the practicability of carrying out the two 
processes simultaneously. Plainly, the problem is that in 
a spent fixing-bath we have much silver hyposulphite (or 
double hyposulphite of silver and sodium) together with 
a fair excess of hypo and with other substances which 
have found their way into the fixing-bath from the 
developer. We take it that when the silver is thrown 
down from such a bath by means of sulphide of potash, 
hyposulphite of potash is thereupon formed in the liquid. 



Unfortunately a liquor, however rich iu hyposulphite, 
which contains even minute quantities of sulphide is use- 
less as a fixing-bath for gelatino-bromide emulsion on 
glass or paper, and it is very doubtful if means could be 
found for getting rid of the sulphide without affecting 
the hyposulphite, and without introducing substances or 
changes into the liquor which would unfit it for use as a 

fixing-bath. 

» * * 

Specimen Some of our readers who overload their 

Displays. windows, showcases, and walk with 

prints, all excellent in their way, might take a hint from 
the expert window-dressers of some of our more up-to-date 
shops, who reduce the number of articles shown at one 
time to a minimum. When the ordinary passer-by sees 
a window crowded with pictures, all at a glance more or 
le^ alike, it makes no appeal to him, and he goes away 
with no definite impression as to the character of the worK, 
but if only three or four distinctive specimens were shown, 
they would command attention and remain in the mind of 
the observfer. This fact has been appreciated by most 
picture dealers. The old style was to put as much of the 
stock as possible in the window and to leave it there, often 
for months without a change. The modern dealer knows 
better than this and shows only two or three pictures at a 
time, with frequent changes. This attracts attention — 
a picture which might pass unnoticed in a crowd of others, 
frequently finds a purchaser. If one compares the display 
in the art shops of the W^est End with those of less 
select character the difference will be clearly seen. It 
is that (between the het'Crogeneous jumble of an English 
drawing-room and that of the Japanese, who only display 
one or two choice vases, bronzes or specimens of lacquer 
work at a time, the rest being carefully stowed away. 
Such a procedure not only minimises risk of injury, but 
it reduces the labour involved in keeping the articles 
in good condition. If care be taken to strike some dis- 
tinctive note every time the window is dressed, people 
will make a point of looking out for a change, while it 
makes it easier for the photographer who does not have 
to prepare a large number of fresh specimens for eacli 
fresh display. 



iVIagnesium 
Ribbon. 



An advertisement of flash powder is 
headed: " Carry your light where you 
carry your camera." This is good advice, and can be 
carried out very effectively by learning to make the best 
use of magnesium ribbon. Every commercial photo- 
grapher occasionally finds himself in a position where 
artificial light is essential to the attainment of good 
results, but does not feel justified in carrying round a 



"SUMMARY. 

The 1918 Almanac is now on sale, and the whole edition hag been 
disposed of to dealers. Intending purchasers should lose no time in 
obtaining copies from their dealer or bookseller. 

In a leading article the question of hypo shortage is dealt with 
not only as a concern of the moment, but -with a view to the future. 
The one thing to avoid in economising is stinting the use of hypo 
whereby the permanency of the print is a£Eec>ted. We point out four 
ways in which to make the most of the fixing bath for negatives and 
prints, and give an easily applicable test for exliaustion of the 
fi.xer. (P. 63.) 

Reclaiming hypo from the fi.xing bath up to the present has not 
received any attention, but a much greater increase in price may 
lead to its practical consideration. (P. 52.) 

Tlie second portion of the paper by Mr. J. A. Orange on scientific 
design in optical projection deals -with the necessary conditions as 
regards diameter and jiosition of the condenser in relation to the 
film and the light, and discusses the effect of varying Iwth. (P. 65.) 

Organisation of one's business and a careful check on the cost of 
production are the essential foundations upon which to build up a 
successful concern. The photographer needs to acquire the business 
sense to enable him to judge between effective and ineffective 
wonomy in labour and materials. (P. 64.) 



Some of the principal features of the recently introduced Patents 
and Designs Bill are briefly referred to by a correspondent on 
page 71. 

Mr. A. Lockctt has made some experiments in reference to the 
" Mackie " line phenomenon, and finds that a large proportion of 
what are thought to be v.hite-line effects have no real existence, but 
are an optical illusion. (P. 67.) 

A recent patent specification describes a method of producing cine- 
matograph advertising cartoons, in which different sets of wording 
may be incorporated with the same moving figures. Tlie process 
consists in simultaneously photographing t-ext and printing of the 
negative, on positive film, without the nse of shields. No special 
cinematograph camera is required, provided there is accommodation 
for a double set of films and for four reels instead of the usual 
two. (P. 68.) 

A field of experiment is open to photographers for the discovery 
of a possible substitute for hypo in the event of a serious shortage 
of this chemiciil. (P. 62.) 

We emphasise the importance to professionals of a slight knowledge 
of elementary optics. (P. 61.) 

The breaking of a carboy of nitric acid in a iprocess engraving works 
R-as the cause of two deaths last week. (P. 70.) 



Kabruarv 8, 1918.] 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



63 



fla-hlight outfit, even were he permitted to use it. But 
with half an ounce of magnesium ribbon, a wooden clip 
With which to hold it, and a box of matches, he is alwavs 
ready for the unexpected. A few hints on the subjw:t 
may not come amiss; to begin with, the ribbon must be 
perfectly bright or it will not bum well, and as the 
surface rapidly oxidises it is advisable to brighten it just 
^)f•■ore it is required by drawing" two or three times 
a folded piece of fine sandpaper: one the size of 
ige stanij)s is sufficient. Bearing in mind that a 
i'lven weight of magnesium yields, when burnt, a certain 
airiount of light, it is desirable to twist several short 
strands together tt form a torch, rather than to attempt 
to bum the same quantity in one length. Moreover, it 
is A safeguard against extinction, as if one strand goes 
out the others will relight it, so that the exj)osure is 
not interrupted. As flaming particles sometimea fall 
off. an old rug, ' or the like should be placed 

so 35^ to prevent, i ; (,e floor or carpet. For singln 

"'')'■'■'* ' ' « ribbon -should be burned behind 

■■ '"-'I'- With 'ir^P s^roups or interiors 

may be ol>t waving the light 

• exposure .: um ribbon affords 

■'''•' '18 of printing very slow developing papers. 

Ii •■ of printing-fr .' . ' .. .1 ...^d in a circle and 

:iii inch or two of ribbon bn itre the very long 

.•!-■.., ,.....^^.,ry when ir. u9*d .ire avoided. 

•he same , ; tv of ribbon each time 
•liKJsure is oijt.-iiiied. 



I 1 >fl IIIIL \ in *•■ 



UK HYPO SCARCITY: WJIAT TO DO ABOUT IT. 

KDisc to our information the present scarcity of 

■ ■"■' •"■ "' T» to amount to a famine. Floating 

y small, but no doubt photographer.s 

>iiy W.1II1.V1 r,y previous have tuk.'n the 

ion to provide tliein-elve- «-l,« ^i||V.. i,.jit (o 

<me 

- to 

with a view 

•> to that of 

tiie luture. Before dealing in 

ts w.- w.,i,M |,e allowed to say that 

which mo-t <eri ild not be done is to 

•• Uie of hypo ai .y to iwue print« the 

y of which i< a of weeks or months. 

'' ■' ' t the shortage of an 

ich a eounu a* this, 
iita- 
I be 



hat there is no workable sub- 

itinn of plates or prints; and 

. .. oan '"^ n,l.I...J to hy|>o in order 

r." A<i u'h as ammonium 

I have til. .11,.. i ui making a fixing 

but thev do not allow of a larger 

■I 111 ].i;ii«-, ..r jirintu '■ ' . .'d with a ■ ight 

po. Therefore a pi ler's onti . at 

i.iclical wavs 

' w,i«fT'e of 

iing 

nay 

in 

: ■ :. ,'.ork 

•y are capable of. How then are baths to do more 

,• work without prejudii-e to the quality and per- 

snenoe of the results! Bro.idly, there are fowr ways in 



>ke It •' 



which a fixing bath, as it is commonly used, could be 
better employed. These are: — 

(1) Rinsing between development and fixing. 

(2) Testing for degree of exhaustion. 

(3) Passing on print fixers for use with plates. 

(4) Keeping at suitable temperature. 

These provisions apply broadly both to negatives and 
prints, but their application is naturally more in respect 
to prints, for the reason that prints occupy a much 
larger proportion of a photographer's output and call for 
more careful supervision as regards fixing. We will now 
take these four points in succession and endeavour to 
indicate simple procedures which photographers and their 
assistants can and should adopt as a means of economy 
in the essential hyposulphite. 

(1) Riming after development. — This applies particu- 
larly to prints, since rinsing the developer from the surface 
of a print very greatly reduces contamination of the hypo 
bath by developer, with its effects of stain and, in 
aggravated cases, of muddiness in prints. In the case of 
papers such as bromide, which are fixed in a plain, as 
distinguished from au acid, b^th, the omission to rinse 
print^s before placing in the fixer will often cause the 
hypo bath to develop a strong colour long before its fixing 
powers are approaching exhaustion. Plainly, economy in 
hypo will result, under these conditions, from cleansing 
the prints from developer before they go into the fixer. 
In the case, of prints of the gaslight type, which usually 
are treated in an acid fixing bath, a brief wash-off of 
developer is in a somewhat different category. With some 
gaslight papers it is essential to use an acid fixing bath, 
and when that is the case there is not much advantage 
in rinsing after development. In fact some papers will 
not stand such rin.sing but yield yellow stains unless 
plunged immediately into the fixer. On the other hand, 
some gaslight j)rints will bear fixing even in a plain hypo 
bath, and at the same time will not suffer by receiving a 
brief rinse between development and fixing. We 
advise photographers to discover for themselves just what 
the brand of paper which they are using will allow, and 
then, if practicable, rinse between development and fixing; 
also, again if practicable, fix in a plain instead of am 
acid bath. Hypo in plain solution goes further than in 
any other form. 

(2) Tfftinri Kxhnuftion. — In the case of plates, we can 
see for ourselves by the slowness with which they clear 
that the fixing bath \a nearing the end of its tether; in 
the case of prints no such evidence is afforded, and it is 
here that some working test is necessary to show how the 
fixinr^ bath is getting on and to avoid discarding it whilst 

retains ample fixing powers. A test of this kind 
.'inyone can a]'ply for himself is as follows: — 
A few ordinary dry-plates — any make, any grade — are 
cut up into slips of, say, one inch width and three or four 
inches length. It doesn't matter whether the plates are 
fresh or stale, nor is it a question of any great importance 
whether they have been exposed to daylight before being 
uaacLJar the test. Preferably they should not be ex- 
pdtgt^Sfl'e than necessary. Our own practice is to cut 
up the plates by a bright yellow light in the dark-room 
and then to keep the slips (without any wrappings) in a 
plate box. The exposure to light which they get in the 
print-fixing room, when taking out a single slip, will not 
do anv harm. One of these slips is then put into the 
fixing bath, which has been in use for a larger or smaller 
number of prints, and a note taken of the time required 
for the white emulsion to dissolve out. If this time re- 
quires to be longer than ten minutes the bath may be dis- 
carded, at any rate for fixing further prints, and it may 
be said that the test, rough as it is, is a pretty fair indi- 



64 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[Febniary 8, 1918 



cation that hypo in the bath has been used up as far as is 
advisable without risking the permanence of prints. Our 
opinion is that a method of testing, such as just described, 
is a better system than allotting so much hypo to fix such- 
and-such a number of prints or postcards. We think that 
a syst-em of allowing, say, one pound of hypo for 150 
postcards (to quote figures which were recommended a 
year or two ago by one maker of postcards) is more likely 
to lead to wastage of hypo than the use of an actual test. 
Moreover, where large quantities of prints are being put 
through it is not so readily applied. 

(3) Print Fixer for Plates. — Inasmuch as almost all 
development papers can now be fixed in a bath containing 
four or five ounces of hypo per twenty ounces of water 
without ill-effect in the way of blisters, it is often possible 
to pass on the fixing baths (which have done duty for 
printa) for subsequent use in fixing negatives. But discre- 
tion requires to be used. Plainly, it will not do to risk im- 
permanence of negatives for a few ounces of hypo. Plates 
differ in quite a marked manner as regards the " clean- 
ness " with which they fix out in a bath which is getting 
nfear to the " off -strength " point; and it is open to serious 
doubt whether some plates will fix completely at all if 
they require to be longer in the fixing bath than, say, 
fifteen or twenty minutes before the white emulsion dis- 
appears. Therefore, in using baths which have been 
employed for prints an eye should be kept on this point. 
In any case such baths should be used in tanks, not 
dishes, in order that a large number of negatives may be 
fixed together and time thus economised; and further, 
the fixing bath requires to be kept up to a reasonable 
working temperature. 

(4) Temperature. — This brings us to our last point, 
which is that the fixing-bath, whether for plates or prints, 
should not be below 60 or 65 degs. in temperature. The 
temperature should be tested with a thermometer, not 
guessed, and the bath requires to be kept at this tempera- 
ture. In the cold dark-rooms which, we fear, in many 
establishments are the rule, artificial Leat is necessary 
for this purpose. In the case of dishes it is unsafe to 
warm by placing the dish directly over (even if some 
distance above) a moderate source of heat, such as a 
small ring gas-burner turned down to the blue. In such 
circumstances it is almost inevitable that the fixing 
solution will not be uniformly heated. If it is left to 
itself for a while it can easily happen that it will get too 
warm in places, and may lead to softening or melting 
of the emulsion coating on prints sufficient to spoil the 
prints at this stage or to give rise to blistering in the 
after-process of sulphide toning. Some means should be 
taken to distribute and equalise the heat. This may be 
done by standing the fixing-dish in a large baking- 
tin containing clean sand or fine shot to the depth 
of about a quarter of an inch, or by placing the fixing- 
dish in a larger dish containing water. Still more neces- 
sary is it to ensure uniform distribution of heat, as far 
as possible, in the case of fixing tanks, wrijch require to 
be stood in a larger metal tank — an old washer can often 
be 'requisitioned for the purpose — filled with water above 
the level of the hypo solution in the fixing tank. By 
taking means such as these, in the case of either dishes 
or tanks, it requires little ingenuity to adapt any con- 
venient source of heat, such as a ring gas-burner, a small 
oil stove, or a single paraffin lamp, to keep th) fixing 
solution at a temperature which will make the best of its 
fixing powers. 

There are several other minor measures which should 
be observed in the economical use of hypo. In making 
up fixing baths the hypo crystals should be weighed, or 
measured by bulk. In the days when hypo was the 



cheapest of commodities it was too commonly the prac- 
tice to make up baths simply by shovelling the crystals 
by the handful into the water for their solution. 

Another point is that, in transferring prints from the 
fixing bath to the first wash water a great deal of hypo 
solution can be carried away and lost. It would prob- 
ably surprise anyone who cares to make the experiment 
to find how much fix'ing bath can be collected from a 
batch of prints simply by allowing the drippings, which 
usually find their way to the wash water, to accumulate. 
If prints are drawn slowly from the fixing bath the 
greater proportion of the solution will be drawn away 
from the surface and will be kept in the bath. 

But perhaps more important than any of these minor 
measures is the practice of keeping prints constantly on 
the move whilst in the fixing bath. Hypo does its work 
quickly and surely and without waste, but not unless the 
hypo solution is brought freely into contact with the 
surfaces of prints and is given the opportunity of pene- 
trating into the pores of the emulsion, whilst at the 
same time the solution charged with the silver salts from 
the emulsion can pass out into the surrounding bath. 
If this essential feature of the fixing process were kept 
regularly in mind we should hear less of complaints of 
stains and the like from incomplete fixing. 



COST AND PRODUCT. 

Wb are living and carrying on business under conditions 
which four years ago would have been considered impos- 
sible, yet on the whole photographers have not done badly, 
in spite of the enormous increase in the cost of all mate- 
rials and the much higher rate of wages which has prevailed 
in consequence of the scarcity of skilled labour. To attempt 
to prophesy when the present state of things will end and 
what conditions will prevail after the war would be a 
fruitless task, but one thing is certain — that money will 
not be so plentiful and that prices will not in our time 
sink to the pre-war level, especially in the case of wages, 
which are, outside "one-man" businesses, one of the 
greatest outgoings in most concerns. It is, therefore, neces- 
sary for every producer so to organise his establishment 
that he is assured that he is receiving full value for every 
penny of his expenditure, and this applies to the smallest 
as well as the largest businesses. 

Photographers as a class are not good men of business, 
not because of any lack of mental capacity, but simply from 
lack of training. In only a few instances can we recall the 
names of those who have made large fortunes, and they 
were business men who never did any practical work them- 
selves, devoting their energies to directing and exploiting 
the labour of others. This is no reason why the photo- 
grapher should not endeavour to acquire the special know- 
ledge and habits which make the difference between 
struggling for a bare existence and piling up a comfortable 
surplus. 

In every successful manufacturing concern the jnanager 
has the words " cost of production " burnt into his brain, 
and next to maintenance, or, better still, improvement of 
quality, they are his chief est care. Hard work does not 
always tend to economy. Some men are so busy that they 
cannot stop to look end find the openings through which 
the results of their industry are leaking away, while others, 
with more business acumea. always seem to have time for 
any necessary purpose without neglecting the ordinary run 
of work. How can we apply this to the photographer? 
The first point to be considered is that of labour, and un- 
fortunately the great body of photographers have not yet 
realised that in buying this, as is the case with most com- 
modities, the best is the cheapest in the Jong run. A 



Febru&ry 8. 1918. ) 



THE BRinSU JOURNAL OF PHOTOGRAPHY. 



65 



ekilfo], well-trained assistant, m^., , ...i be relied upon to 
cif veiop batches of plates uniformly and well and turn out 
his ta!e of perfect prints without constant watching, may 
command ten or even twenty shillings a week more than a 
duffer; but the stving of material, not to speak of the 
r« lease of the principal for more important work, will soon 
show a b.; lance on the right side. It may be urged that 
such assistants are difficult to find, but it they cannot be 
i( iinil they must be made. The general entry of women 
iiit" all branches of tli« prof ession nas made a great difler- 
ence in this respect. Leaving out operating, a field in which 
women certainly have made good, we have dark room hands, 
platinum and bromide printers who were formerly 
!<potters, who have taken up the new work with enthusiasm 
since 1914, and can i.ow give points to their male pre- 
'Icoessors both as regards quality and quantity. One error 
most be avoided, and that is of endeavouring to get efficient 
female labour at a lower rate than should be paid to men. 
We are convinced that such a policy ia a mistaken one. In 
II I'.- Midios, even now, girls are employed at wagee on 
V • -y could not exist if they were not living with their 

■.'ho are thu.^ indir^.-t!y subsidising their employer's 
How can it be f .x[>ected permanently to attach 

.'!• i; nt-rest to the business? 
<".'>••■..■ connected with the efficient and well-paid 

1 i-tant ia the qu»>stion of economy of platen and other 

I' •riaU. The worker who realises that his future 

'pcts and general well-beiii'^ are bound up with those 

^.i ii.i employer is not likely to waste material hinuelf or 



to allow others to do so. By careful attention to storage 
and wrapping alone, several pounds a year could be saved 
in the matter of mounts, phites and paper in studios of even 
moderate size, r.nd this could be added to by equal care in 
the mixing and use of chemicals. Where bromide paper 
is used from the roll it is often cut to waste, and very often 
there is much paper wasted upon trial prints for which a 
fragment would have sufficed. All these economies may 
seem trifling and .ilmost unworthy of notice, but in a case 
recently under notice they resulted in a saving of £50 in 
the year, and there are few photographers who would refuse 
that sum even at the cost of a little vigilance. 

Cash discounts afford one of the easiest ways of making 
or losing monoy, whichever way one likes to put it. If 
•J per cent, is lost by not paying promptly eacn month, it 
comes to 6C per cent, per annum on the amount of one 
month's purchases. Surely it is worth while to save this 
by di^ipensing with all unnecessary expenditure until every- 
rhing is paid up to date and full discounts taken. Slack- 
ness in bookkeeping is another way of dissipating profits. 
If statements are not regularly and promptly rendered, 
removals, deaths and otiher happenings may render re- 
covery of debts difficult if not impossible. Steady, polite 
dunning will be found the best policy. More than one 
business has learned to its cost that a long period of slack- 
ness followad by drastic measures in the County Court is 
rot the way to retain popularity either with bad payers or 
their friends, who might be desirable customers in the 
future. 



SCIENTIFIC DESIGN IN OPTICAL PROJECTION. 



II 



The projection of motion pictur<!t, whil<> optically but an 
nut^rowth of magic-lantern work, is relativtily ooiiifdicated 
by the pnaanot tk peculiar features. The simplnft mode of 
ooBwderatioa ia to omit all retferenoe to the tiLm m<)>*«nMiit 
and shutter action in th» fint instance, the problem being 
thou rcditoed to tile pn>j«etion of lant«m abdea 2.5 cm. in 
diameter aa against 10 cm. One has, aa before, an objective 
for th« aotosl projection of the pictai*, and juat as in the 
case of the ms^c-lantera previooaly diaruavd the limiting 

illoroination at tba screen is '^ k, and the ideal mean 

of attaining it woald be an eztondad faadt^round of toaroa 
fttirfaoe beiund the alide (Fig. 3a). Tlus is as impracticable 
.1* in tl»e case of tha magic-lantcim proper, afid the logical 
tKine to do is to pnyride a cond tmar immediately behind 
'l-io ^!]'l». followed in tarn by a hght-aonroe surface. Even 
tUi'< ijitiiatuns edition of the ooaiplet* magic-lantern is 
'hi!. I ' to am azespt in amateur woric. The reason is best 
ffn injm a nnmarical example. 

A ragnlar magic-lantern might disclose the following par- 

fti-'i'iir^ 

-- I" diameter .. 10 cm. 4 ins. 

36 cm. 14 ins. 

4 cm. IA ins. 

■M 1 cm. I in. 

-<-« to condeiiMr 10 cm. 4 ina 

Now, u one v»i- " from »lide to film 

(i.e., 10 cm. to 2.5 *ize and iUumina- 

tion the same, t! .•••.••<b<iig wouUi be about the 

•rfl^TTlO 

2.5 cm. 1 in. 

length 9 cm. 34 ins. 

ive apertur- 4 cm. ij in*. 

/e 1 cm. I in. 

' kwraiKtf, svuroa to conden-- r Z5 cm. 1 in. 



What one may term the factor of clearance, i.e., the ratio 
of tiie last two terms, constitutes a serious difficulty because 
of the marked heating effect on the condenser and on the 
lamp Itulb, if there is one. This difficulty becomes less 
marked in the cvses where a smaller screen picture will suffice, 
and, in fact, there are successful amateur outfits designed 
along these lines (Figs. 36 and 3c). 

To SToid this trouble it is well to arrange theatre outfits so 
that instead of having a small condenser immediately behind the 
film one has a larger condenser further away. So long as the 
outlook throuKh the film from all parts of the objective opening 
is faced by coodenser surface, limiting illumination at the 
screen ia possible, subject to the inevitable condenser losses 
(reflection, absorption, and, in the case of Freenel lenses, inter- 
ruption between rings). (Fig. 4a.) 

There are an indefinite number of possible condeneer posi- 
tions, the greater the distance from the film the greater being 
the diameter of condenser required to give limiting illumination 
over the screen. The single advantage of increased light-source 
cleacanoe has to be set off against increased absorption and 
increased cost as well as a slightly decreasing economy, i.e., tlie 
mora remote condenser positions require a slightly larger extent 
4>£_si>aMe if the size of the condenser, but not its form, be 
vorlSil'). For these reasons it is well to adopt a condenser posi- 
tion which is as near the film as is consistent with a satisfactory 
light-source clearance. The maximum useful extent of conden- 
ser opening in any plane is defined by the locus of points from 
which it is poesiblo to see through both aperture plate (the 
frame of the film) and objective simultaneously. The best 
position for the light-source and the maximum useful extent 
in that position are most easily determined by back-testing as 
described in the maRic-lantem section. This point should be 
notioer], however ; for some condenser arrangements back-testing 
will reveal two well defined spots in different planee, one being 



66 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[Fflbraary 8, 1918. 



reotanfiular and the other circular. N.aturaUy the smaller spot 
is the more economical source-position, and eitlier spot may be 
the smaller according to circumstances. The only kind of 
source which may be placed in correspondence with the rectang- 
ular spot, however, is one devoid of structure, such as a flame, 
because any light-sov/rce structure vfill he more or less clearly 
imaged in the film position cmd in turn on the screen. With 'a 
rough light-source it is essential to place it nearer to the con- 
denser ; how much nearer is a question which depends on the 
degree of roughness of the light-source {coarseness and con- 
irastiness of structure), the relative aperture of the oibjoctive 
and the degree of evenness desired in the screen illumination. 
In the case of a suitable tungsten-filament and oustomarv 
objective aperture, it is sufficient in practice to adopt the 
sharpest circular spot as light-source position. (In short, while 
a perfectly smooth source may sometimes advantageously be 
placed conjugate with the film, a rough light-source must be 
placed more nearly conjugate with the objective opening.) 

It is advisable to consider at this stage what effect is 
fvroduoed in the general case, if one " stops down " or reduces 
the opening of a condensea- so that it no longer satisfies the 
pjimary condition for limiting iUumination over the screen. 

In geneiral the condenser opening is imaged some little 



■t 



4 



C«) 



a:> 



rW 



(c:) 




Fin. 3. ^Motion Picture Systems. <n) Ideal. (*) Magic Lantern Type ; adapted 

for theatre use. (c) The ^ame adapted for amateur use. 

distance ahead of the objeotdve. (It may he readily found 
by using a slip of paper.) 

Ilhe effect is this : From any viewpoint on the screen one 
sees as much of the objective opening at standard brightness 
as may be seen through the imaged condenser opening. Thus 
with some particular exiamjple of condenseir opening it may 
happen that central points on the screen have a view of 
the objective opening quite unrestricted by this imaged open- 
ing, while peripheral paints axe not so fortunate. The result 
is a waning illumination as one moves towards the edge of 
the screen, a so-called vignetting action. 

It is important to notice the various stages in the transition 
arising from a gradually shrinking condenser opening in the 
general case where the condenser is not very close to tlie film. 
First, witli tlie condenser opening sufficiently large, limiting 
illumination is possible at all screeoi-points. Reduction of 
the opening is first effective in a slight darkening of the 
comers of the picture. The effect becomes more marked, and 
eventually it is impossible to get limiting illumination even 
at the centre of the screen. Carrying the reduction of the 
condenser opening fuxther and f ujrther, the screen illumination 
steadily decreases, but it becomes gradually more uniform. 
At; a certain stage it becomes quite uniform, and although 
furfchear reduction of condenser opening leads to decreased 
iUnmination, yet the distribution stays uniform. These 
changes are illustrated in Fig. 5, representing the distribu- 
tion along the diagonal of the soi^esi. 



It may well be asked, of what interest is it to consider any- 
thing but the primary condition in which the condenser open- 
ing is large enough to secure limiting illumination all over 
the screen ? 

The extreme case of resti'icted condenser opening is very 
interesting because it is a condition advocated and practised 
largely in the theatres to-day (Fig. 46). That is, a plano- 
convex condenser system of 4 in. (10 cm.) opening is often 
placed at 15-20 in. (35-50 cm.) from the film. The arrange-" 
ment approximates to the stage e shown in Fig. 5, low, but 
unifoi-m illumination. There are advantages unconnected 
with illumination associated with this arrangement ; these 




Fig, 4 Motion Picture Systems, (a) Tjarge remote condensar for limiting 

illumination, (&) Small remote condenser for low, even illumination, (e) Use of 
a field lens adjacent to the film. C=condenser, F=lilm, CI = image of condenser 
opening. Outlines of useful beam shown in each case (for shutter de&ign). 

advantages will be related later and shown to be over- 
estimated. 

The case of a slight restriction of condenser opening is of 
practical interest for the following reasons. The slight vig- 
netting is not a serious disadvantage at least ; some even go 
so far as to claim it as a positive improvement of the picture. 
There is quite an advantage in being able to use a smaller con- 
denser size, both on account of cost and, more important, the 
saving in thickness of glass which results in an improved 
source-clearance. 

To summarise, the condenser for motion-picture projection 
may conform with any of three conditions : — 

(1) Miniature magic-lantern arrangement ; condenser a little 
larger than the film and placed close behind it. 

(2) Condenser at a distance from the film and of such a 















.^ „.- __. 












j 


'' ^^ ^::. 












y 


^ ?■ "^^ 














7 \ 






la: 








:u s, ^ " ! 






































































_ 0_ 












- IS 


nS- 




























l_ 




















A 








- ^ ■. E _ 












* 














^. 


























^- 







Fig. 5. — Distribution of illumination along screen 'diagonal as affected bj 
relative opening of motion picture condenser; openings diminish from (a) to (/). 
ab80ifisae=points along screen diagonal— ordinates^intensities. 

diameter as will lead to limiting illumination over the screen, 
or at any rate over the greater part of the screen. 

(3) Condenser at a distance from the film and of such small 
diameter as will give even, or practically even, illumination. 

(There is a fourth arrangement which has had various sup- 
porters ; this employs, in addition to the condenser proper, a 
small field-lens close to the film such that the condenser opening 
and objective oipening are respectively conjugate, or in the rela- 
tion of object and image. Lack of spare forbids moire detailed 
mention. (Fig. 4c.) 



Fekruaiy 8. 19ia] 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



67 



At regards the form of condenser best suited to motion picture 
projectorB, a few remarks may be af interest. 

Amateur outfits using the magic-lantern arran^ment will 
^iv© satisfaction with plano-convex condensers. The mode of 
oixrati. .n resembles that of the an: lantern ; that is, the effective 
apt»nurf IS less than the gross L-jf-ninc:. (Fig. 3c.) 

Corr-ited, i.e., non-spherical. < have greater pos'^i- 

hilitit-s with such outfits, but it _v a question of cost. 

Such condensers would be ver>- dt'sirable if any attempt were 
made to nae this arrangement in theatre work ; in fact, they 
would almost be essentiaL (Fig.Sb.) 

Of the other condenser positions, it may be said that tho 
noospherical oonstruction is always an ad>'Bntage in spite of 
the fact that spherical aberration is not always a detriment 
(in limited amounts). There is always a asving in lens thick- 
neai. and benoe a diminished absorption and an improved 
source clearance when the corrected surfaces are used. 

A pecaliar form of condenser of the FrMnel type can be used 
for any position not immediately adjacent to the film. In 



estimaitine the relative utility of such a condenser it is neces- 
sary to set off til© advantages of small thickness (hence low 
absorption and good source-clearance) and cheapness against 
the <lisadvan>tages of considerable " discontinuity " and surface- 
scatterin<r losses. 

(A Fresnel lens necessarily has inteirruptions of aperture 
between the prismatic rings ; in its aperture relations it is 
analogous to an ordinary condenser having black paper rings 
pasted on it) 

There is a possibility which has not been discussed, namely, 
the use of an extent of source which is smaller than that really 
called for by the optical train. This alternative, which in- 
volves using a smaller effective aperture of objective for any 
particular screen-point than would otherwise be used, cannot 
be adequately treated here. Tho resulting illumination is 
correspondingly low and there is no apparent advantage asso- 
ciated with this arrangement. 

J. A. Obanoe. 
(To be continued.) 



THE "MACKIE" LINE-SOME NEW FACTS AND EXPERIMENTS 



The (oUowintt article i« not intended to traverse the aoceiited theory 
that the Mxalled " Mackis " line is doe to nnuied developer in 
tiie shadow portMMM o< the n<ig»tive rsinforcing the solution in 
Um adjoornt strongly ht poru, in the abseocs of rocking, and 
thtu canaing a narrow band of gU'AtvT opaoily to eixToach on the 
l;i;ht» and to print u a li,{lil«'r line. Neither is it wished to 
deny the miaonty contention ttwt amilar result* have been ob- 
l*in«d (roio other and, at present, obsenrs eausea. It is merely 
desired to point out the carious (act that * large proportion of 
what are tbou(;fat to b« white-line eileoto have no real existence. 



The writer '■ 
examination <>: 
a(^nst a dark uiu 
line was itraigbt, a: 
ot cases the osrraw 



.wle a series of ssperimenis in the visoal 
vhere a white or light tone oame abruptly 
- for convenience those in which the 
■•> hit nurprise, that io quite a number 
! ul greater bnghtnees inside the edge ot 
th(> tighter pnrtinn wan tinmiftakat'ly vinible br4,h in the subject and 

'to independent 

" negatives. 

U was ubvwuaiy nicmssry, briufc loiy woiglit could be attached 

to the evidence, to ascertain that the effect was not aa optical 

illiuion, (or Ike aiars fact that varioas people agreed in seeing 

it wM insofBdciii. Several methods wsrs adapted to ^cck this. 

V.w- r:ineot 1 : — Ezposores were mada <m a few selected sobjeoU 
•h'>w.!jj the line on the foeossing iflresn, using flat films. On 
development, the line of greater opacity was distinoUy seen in 
the active. When dry, the fifan was cut carefully along the 
boundary beiweca the mssies of ligfal and shade. Result, the 
lino dmtppeared and ooold not be detected, even with a good 
ti. v<r. ;'. rig leas. It reappsared, however, on potiing the halves 
t.. .••■•.!.. t agaoi. 

Ki|/<rment 2: — A negative diowing the white line was enlarged, 
the lifMH being vety clearly visible in the solargemeat, thoogfa assm- 
ingly not moch wider. The latter was tboD col across at tiia shadow 
briiinrliry. the line sgain disappmnng. 

Ku-rineot 3: — Several nrt;a(iv(« in which ths line oocnrred 
were held op lo the light, and the niore tran^Mrent portion of the 
image was covered with a card up t>j the boundary. Result, instant 
vanjahing ot tha deossr liaa. This happsoed in abnoat evacy ams. 



\» a guide to those who would like to repeat these experiments, 
the line may be sought for where the margin of an archway or 
other opening meets a brightly lit view beyond, the line, of course, 
being at the boundary of the view, not of the archway; at the 
edges of flowers and their stalks, against a darker ground ; at 
the edges of the ooat«, hats, hair, or faces in portraits, when these 
are lighter than the background, or just external to them if the. 
background itself is lighter; round the sails of yachts against the 
sky ; round roofs, chimneys, spires, etc. Generally speaking, the 
illusion is more likely to be present when the light and shade are 
both of an intermediate tone, rather than a dark black or a pure 
white, the outline or junction being somewhat soft instead of 
sharply defined. 

The writer next selected about a dozen photographic prints, 
including portrait, landscape and architectural subjects, several 
engravings, a number of half-tone reproductions, and one or two 
coloured lithographs, all showing the pecuUar line, and ascertained 
its visibiUty to different observers. By similar cutting methods, 
however, or by covering op the darker part of the imago, with a 
card approximately the same tone as the light ground, the line 
was foimd to take flight, except in seven instances, three being 
photographs, two engravings, one a half-tone, and one a lithograph. 
With respect to the three photographs and the half-tone there were 
no data available on which to base an explanation of the white 
line, bot in the engravings and the lithograph it seemed to have 
been delibezately introduced by the artist — a not uncommon prac- 
tice — OS it sometimes gives added relief and a better impression of 
roundness. Tlie line, in tact, is often a beauty instead of a defect. 

Anyone may readily familiarise himself with the remarkable 
optical illusion that has been demonstrated by cutting a disc of 
black paper about i inch, diameter and pasting it on a white 
card. On looking directly at the disc a much brighter ring will 
be plainly seen outside the margin. If a white disc is mounted 
_cr- . H'- '■ card, the lighter ring will appear inside, though it is 
J -• striking. It seems to grow more distinct if the eye 

is Kejit oil it for a few seconds, and is possibly partly a contrast 
effect, partly an overlapping " after-image" due to retinal fatigue. 

A. LOCXETT. 



Dkt Stoslacb.— To many the k1p.% may be old, as, in fact, it is ; 
l>'it. js a matter nt axpsrisDce |wnt<<s Mr. H. B. Morgan, of Hhos- 
ofi d«a, to the " Phannacantical Journal"), I have found that few 
pharmacists realise the vafaia of a I'lrge box with a well-fitting lid, 
liia lower part of the box filled with lumps of quicklime, as a recep- 
tee^ in which goods may be kept perfscAly free from moisture. In 



the Esst, where at certain seaaoos the boots I look off at night wotdd^ 
have a growth of mould by the morning, and everything was damp, 
warm, and sticky, such boxes were invaluable in preserving certain 
drugs, photographic papers, etc. In England tiie lime is a long 
time before it slakes, and the whole arrangement gives but little 
trouble. 



G8 



THE BRITISH JOURNAL OF PHOTOGRAPHY 



[February 8, 1918. 



Jlsslstants' Roles* 

— • — 

Sou* by assiitants suitable for Ma column will be stjuiii»rtd 
and paid for on the first of the month following publication. 

A Handy and Inexpensive Lamp. 

'Hebe is a little idea of my own which I suggest as being very 
-useful, cheap to make, and very economical in use. All that is 
required is a screw-top metal-polish tin, a nipple from the gas- 
fitter's, with one end tapered, price one penny (a, fig. 1), a little 
Bolder, and some wick. 

First of all, make a hole in the centre of the ecrew-cap suflBoiently 
large to take the straight part of the nipple, and solder the two 
•together, aa at 6. Providing the nipple fits tight enough in screw- 
cap, the solder is not necessary, although, of course, it makes a 
much better job. 

Xow thread the wick through the nipple (which is now the 'burner), 
just suflScient to give a good light without smoking. Puncture a 
very small hole near the screw-cap in the metal-polish tin to admit 
air as the paraffin is burned. Now fill the tin with paraffin, screw 
on the burner, and the lamp is ready for use. 

If left burning overnight it helps considerably in keeping the 
developing solutions, etc., from getting below normal. As proof of 
■this, I have not had any glacial acetic acid frozen since I burned 



m-cA- 



fo acfmit air. 




er 




-one of these lamps overnight ; in fact, I have several in use, some of 
■which I have blacked, and fitted with a small holder to carry an 
•opal ahade. Although this is not necessary, it gives a smart appear- 
ance, and the lamp answers quite well for lighting up dark passages. 
My lamp which I made in this way has iburned over 100 hours at 
a cost of one penny for paraffin, and it looks as though it will burn 
for another fifty hours yet. In these days of scarcity of matches 
-one or two of these lamps are a great convenience. Keep one near 
—but not too near — a gas stove. Use it for lighting a paper spill. 
— ^Habry Duckworth. 

A Simple Retouching Desk. 

-A LARGE sheet of three-ply wood, stiffened with battens, forni.s <iji 
ideal retouching desk by merely making one or more apertures 
.and leaning it against a window. Tho top batten, with advantage, 
may be a little longer than the iboaixl, so as to engage on a pair 
oi hooks or other simple supiports on the window -frame. This 
will prevent slipping of the desk and ensure rigidity. If there 
is a clear light from the sky, a piece of ground-glass fixed against 
■the window will be good to work by, ofiherwdse a reflecting board 
is required, wlhicfh may be just a sheet of wliite cardboard sup- 
ported by a box, or can be a boyird hinged to the desk itself. 

While working, ithe window-blind (preferably not an opaque 
•one) is brought down just over the top edge of the desk. In this 
way two ipeople can work in comfort, with plenty of room to move 
"both arms and negatives, and without the partial suffocation and 
cm-sequent dixfwsaness often associated vwth retouching desks. 
Another advantaige is that sut'h a desk is instantly removable, and 
it /U<ke atyt collect dust. — D. B. 



Patent ReiDS* 



Process patents — applications atid specifications — are treated in 

" Photo-Mechanical Notes." 

Applications .Tainiarv 14 to Januai-y 26 : — 

Washers. — No. 1,043. Apparatus for washing photographs. 
P. H. Waddell. 

CiNEMATOORAPHT.— No. 1,253. OinematogTaphic projection ap- 
paratus. E. E. Halford. 

COMPLETE SPECIFICATIONS ACCEPTED. 
Theu specifications are obtainable, price 6d. each, post free, front 
the Patent Office, 25, Southampton Buildings, Chancery Lane, 
London, W.C. 
|7j« date in brackets is tluit of application in this country ; er 
abroad, in tlie case of patents granted under the International 
Convention. 
Cartoon Cinem.^tograph Films.— No. 112,210 (Jiarch 27, 1917). 
The invention rdfates to cartoon advertising films consisting of a 
series of moving figures accompanied by suitable wording. It 
consists in a process for taking the films such that the same series 
of moving figures can be incorporated with different sets of 
wording, and thus used for different advertisers. 

In making the negative film of the action the stage or field is 
aaranged with a black background and light or white drawings 
and with no shielld to provide for text on the positive film. The 
successive action set-ups are photographed upon the negative film 
in any suitable moving picture camera. When this film is developed 




Pig. 1. 

it shows a white field with black or dark surfaces or lines thereon 
depicting the action. A space is, of course, left on the field in 
wihioh the text will appear in a completed positive, but no 
framing or shield is required for this space. 

For the text the photographing field is white. The lettering is 
placed thereon in black in reversed position. Tliis may be 
accomplished in any suitable way. 

A moving piotui'o camera is provided having any suitable 
intermittent mechanism, but with provision for running two films 
through this mechanism at the same time. This is doiie by pro- 
viding two reels in addition to the two ordinarily used in the 
camera. These two additional reels are to hold and rewind, 
respectively, one of the two films that are to be placed in the 
machine. Tliere are aUo suitable guide.? to bring the extra film 
into contact with the other one as it jwsses through the film 



.la 



TILE BRITISH JOURNAL OF PHOTOGRAPHY. 



©9 



ohumrf ^t Um war ' •* 
ii>*-''i ■•^'- of the r^""' 
di-.4. r i I i u placed 
tlirv t'i- i thfoacli thi- 
'he ucz-^uve film aesuc't 



rei 



^u niiii> 



' mulsion aides together, and wiUi 
liie lena. The perl'i orations in the 
two filiiM are engaged mroaHaneoosIy by the te< t!i of the feed 
ie^n, and bbe fUms are ihui positively maintained in proper 
relative poatian. It is not necessary to teke any pains to 
t'gister the two fiima. beoanee, evidently, the positive fibn has 
^loi been azpoaed, and it ia only necesiary to briii(; tiie iilin« to 
oocli poaition that the firat negative piotare that ia to have a 
tait i]io»rpQrate<i with it on Che poaitive, ii in position behind 




FiC- 2- 

'.he Uaa. Thia loxt being set up on the etage, th« operating 
-nachaaiMB of the oamen ia aotoate'l .ne times, and the 

-aya ct Kght from the fi«U paaa ti. - ramers 1«m, and 

'tiroagh the clear part o^ the negativi- film raaerved for the text 
•r«t) pbotogiaph tbe white field a>wl black iHtering apon the 
ve film. Tliia part wh«a deve^ped will, of ooarae, riiow 
" latt«n upon a biaok baokgR>titi<i. At the aame time the 
iotcnae tight paaai^g tiuoogh the koa from the white field pene- 
trates at] the olh«r pacta o( tha oei^ativa and prinla the dark 
parts of the oogativa on the poaiiive film, which, when developed, 



2"© 



/S 



^^^\^r*»T'*0^itrmm, 



y 



p"l 






■Lrf» 



^Jy 



Kg 3. 



>i ^ ihua produced 
xt and printing of - 
.,:* u dune withaut 
' ithoot the ose of •' 
' lie poaitive la - 
nijle "Tp^iaare, 

irface. lite ou<n(>Uit«>l 
' hW-k bAcksranod, whilo 



'-• of the action in white 

'« a photographing of 

'1 tiKi» poaitive film, and 

''•giatry of films; 

'>ind produced ou 

is piTKlaced at a 

^ ngte and uniform 

t alktwa tbe desired lieht 

I one complete 



>l«d. 



y eliminated and other tedaooa and 
the placing o( ihielda, etc, are also 



advantage erf the pntceM \* that H parmtta inaerta, each 
^ rrprodocUooa ol engravings m .Irawings of tlie particular 



advertisers goods, to l>e added to the positive film in conjunction 
vfith the tc.xt. In carrying out this part of the invention a paper 
negative print is made of the desired cut, drawing or typewritten 
matter, and this negative print placed ou a suitable part of the 
field at the same time Uiat ie-sX matter i.s being photographed. 
Allowance of space for this added text matter will, of course, have 
to be made in preparing the negative film. , 

In the drawings Fig. 1 is a diagraniniaUo view of a moving 



/Xec^rrnf 




f/fmr 




Fig. 4. 



Fig. 5. 



picture camera arranged over a suitable table or stage, and the 
stage in ti»m arr&uged for the photographini: of the text; Fig. i 
ia a longitudinal section of a suitable moving picture camera pro- 
vided with extra spools for positive films ; Fig. 3 is a diagram- 
matic view exemplify ins the printing of the negative upon tlie 
jKwitive film and the simultaneous photographing of the text; 
Fig. 4 ahowi a abort section of a negative film ; and Fig. S shows 
a ahoit McCion of the completed print or positive film. 
Reginald Victor Stambaugh, 1,222, Ontario Street, Cleveland, 
Ohio, U.S. A. 



jinalectde 



MjttracU from our wteUy and monthly conttmporaria. 



Pasae-Partout Frames. 

This is the time of year when trouble is rife with prints framed in 
paaae-partout stylo (says a writer in Fhotoyraphy and Focus ior 
February 6) Bl.<ce»sive damp may loosen the binding strips. If 
dealt with at once tl is may be remedied by drying the glass and 
pressing the damp binding again into contact witil a duster. But 
a more serioas trouble arises when the prints are hung by means of 
small braaa ringa secured by paper fasteiiers paaeed through the 
backing board. Thes> rings, made of very thin brass, are exceed- 
ingly perishable. Sooner ur later they give way and the frame falls. 
To take the whole arrangement to pieces, replace the rings, and re- 
liind ia a tiresome operation and involves a recurrence of the same 
trouble in the future. .\' better plan is to discard the rings alto- 
gether. Two strips of stout tape can be folded and stuck down on 
the back a convenient distance apart, leaving about an inch free 
at (he doubled end. A patch of paper is then pasted down on the 
b/ick. covering the tapes, with the exception of the free loops, through 
VI hirb the cord ito sus|>(.'nd the print is then passed. 



FORTHCOMING EXHIBITIONS. 
February 2 to 9. — South Glasgow Camera Club. Secretary, John 

Baird, 164, King's Park Road, Cathcart, Glasgow. 
February 9 to 16. — Glasgow and West of Scotland Amateur Photo- 

jW|{| y^^««o n»tinn Secretary, G. S. McVean, 125, West 

BsgSMt Street, Glasgow. 
February 16 to March 2.— Edinburgh Photographic Society. Sec., 

P. T. Mackintosh, 38, Castle Street, Edinburgh. 
February 21 to 23. — Leicester and Leicestershire Photographic 

Society. Sec., H. C. Cross, 80, Harrow Road, Leicester. 
March 12 to 15. — Hackney Photographic Society. Sec., Walter 

Selfe, 24, Pombury Road, Clapton, E.5. 
April 18 to May. — Hampshire House, Hammersmith, Photographic 

Society. Entries close Mardi 19. Sees., H. T. Callonder, 10, 

Acre Lane. Brixton, S \V.2; or \V. T. W. Sliiers, 201, Goldhawk 

Road, London, \V.12. 



70 



THE BRITISH JOUEINAL OF PHOTOGRAPHY. 



[February 8, 1918. 



meetlnas of Societies* 

— • — 

MEETINGS OP SOCIETIES FOR NEXT WEEK. 

MoSDAV. Peuruary 11. 
Dewsbuiy Photographic Society. " PhotoRraphy mid Art." E. R. Blakcley. 
Bradford Photographic Society. Kxhibition of Pictorial Photographs by Leeds 
Camera Club and Leeda Photographic Society. 

Tuesday, Pebrcary 12. 
Royal Photographic Society. Ordinary Meeting and .Annual General Meeting. 
Birmingham Photographic Society. " The Dolomite Country and Dalniatia." 

Walter Barrow. 
KeiKhlcv and District Photographic Association. "Airedale." T. Mountain. 
Stalybridue Photographic and Scientific Society. " Lantern Slide Making.' 

J. Wal«b, 
Hackney Photographic Society. Annual Sale. 
Manchester .Amateur Photographic Society. Monthly Meeting. " With „ 

Naturalist on the South Coast of Devon." A. Bradshaiv. 

Wednesday, Februauv 13. 
Croydon Camera Club. "How I Constructed and Fitted Up Our Dark Room.' 

B.J.Rose. 
Photo-Micrographic Society. "Some Effects of Micro-Organisms on the Growth 

ot Plants." Prof. W. P. Bottomley. 
Bristol Photographic Club. "The Alp's of Savoy and Valais. ' Mr. A. Coles. 
Iltord Photographic Society. " Oil Transfer Process." F. T. Coupland, B.A. 

Thursday, FKintuARY 14, 
Liverpaol Am.atcur Photographic Association. "Studio Portraits and Pigur 

Studies at Homes." E. 11, Burnett. 
Hanley Photographic Society. Y.M.C.A, Members' Night, A, Hawley, 
Hull Photographic Society. Excursion Reminisccncas. J, W. Atkinson. 
Stockport Photographic Society, " The Town We Live In," H, A, Potter. 
Hammersmith (Hampshire House) Photographic Society, "St, Valentine's Day " 

T. H. B. Scott, P.R.I. B.A. .F.R.P.S. 
Rodley and District Photographic Society. " P.O.P. Printing and Toning " 

W. Barrens. 



ROY.IL PHOTOGRAPHIC SOCIETY. 
Meetinq held Tuesday, February 5, the President. .Mr. John H. 
Gear, in the chair. 

A lecture was delivered by Mr. F. F. Renwick on tjhe " Relations 
Between Optical Intensity and Quanltity of Deposit in Prints." 
^^^l6n the paper was printed ihe said he proposed to alter the title 
to "The Covering Power of Pigments, with Special Reference to 
Photograpliic Prints." This covering power was a most important 
matter not only in photography but in many other subjects. In a 
general way it was (familiar to most people ; white lead, for example, 
had good covering power as a very thin coating, and would obscure 
the surface on which it was laid; while barium sulphaAe, some of 
the substitutes for white lead, and other pigments did not cover 
well. A deposit of finely divided silver had, perhaps, greater cover- 
ing power than most other pigments, but that process varied accord- 
ing to the conditions under which the deposit took place. Practical 
men had long recognised that, and by trial and error had made 
themselves acquainted with the conditions which governed the value 
of the deposit. The lecturer helieved himself to be the first photo- 
grapher to investigate the subject in a -quantita/tive manner in his 
paper on the under-exf.osure period in theory and practice. This 
paper was followed by that of Messrs. Jones, Nutting, and Mees on 
the sensitometry of photographic papers ; but whereas these gentle- 
men, dealing with the theoretical side of the subject, made allow- 
ance onJy for the three factors — the reflecting power of the paper, 
the reflecting power of the surface, and the absorbing power of the 
pigment — he proposed to introduce and allow for another factor, 
w'hich might be regarded as of great importance, namely, the 
reflecting power of the pigment itself. Along these lines the 
lecturer proceeded to, develop a theoretical solution of the problem 
of a somewhat complicated character, which, however, was shown 
to be capable of simplification and testing by pi'actical measurements. 
Tiie .results presented appeared to bear out the author's contention. 

In the discussion which followed, Mr. W. B. Ferguson referred 
to the difference between the pigment in an engraving and in a line 
drawn in Indian ink. They might appear to be equally black, yet 
everyone felt that there was a difference in the value of the colour. 
Mr. J. W. Lumb said the lecturer's methods of exposition were so 
clear thaJt he beguiled even those who had no knowledge of the 
subject into thinking that it was one with which they were in- 
timately acquainted. 

At the close of the meeting 'the heartiest tlianks of those present 
\vere tendered to the lecturer. 



Stalybbidge Photographic and Scientific Society.— The 
seventh annual general meeting was held at headquarters, Astley 
Cheefcham Public library, Stalybridge. on Tuesday, JaJiuarj- 29, 
Mr. J. Lees presiding. Officers elected for 1918 are ; — Patron, Col. 



Sir John Wood, Bt., M.P. j president, W, H. Rhodes; vice- 
presidents, Aid, A, Bottomley, Councillore J, G, Lowe, Mra. 
Summers, P, Talbot, M.B., F.R.C.S., T. Cook, Canon J. G. Bird, 
Di'. G. B. Howe, D. Iiines, D. McLaren, and R. Ridgway ; hoji. 
secretary, W. Harwood ; 'assintairt. hon. secretary, J. Welch ; hon. 
treasureir, C. H. Moore ; auditons, C. T. I. Gamer and J. Leee j 
committee, J. Batty, S. Beaumont, J. K. Gartside. Sergt. F. Hilton, 
J. H. Holland, J. S. Kershaw, J, Lees, Sergt,-Major C. H, Mort- 
lock, J, W. Pickering, A. .1. Parry, J. Taylor, W. Whitehead ; 
lantemists, J. Batty, J. Welch, G. Sykes, R, Longbottom : Lanca- 
shire and Cheshire Photogra/plhic Union delegates, J, S, Kershaw 

and J, Welch, 

^ 

Reios ana Rotes* 

— » — 

Death of an Old Photographer, — Aldeburgh has lost one of its- 
oldest inhabitants by the death on Thursday, Jamiary 24, of Mr, 
John Chalrles Clarke, artist-photographer, who had reached the 
mature age of ninety years (within two moatlie). Mr, Claa-ke 
worked for most of the nobility around Norfolk and Suffolk, 
and his miniature woa-k was greatly praised. Even at his great age- 
he recently painted some exqijisite miniatuj'es on ivory, a fine art 
for which he was justly celeibrated. He passed peacefully away at 
Dalkeitn House, High Street. 

Phoiomicrographic Society. — The next ordinary meeting of the 
Photomicrographic Society will be held on Wednesday, Februsiry 
13, at King's College Bacteriological Laboratories, 62, Chandoa 
Street, Charing Cross, W.C, at 7 p.m., when Prof. W. B. 
Bottomley will give a lecture entitled " Some Effects of Micax)- 
organisms on the Growth of Plants." This lecture is of special 
interest, and visitors are cordially invited. CaJds of invitation 
may be obtained on ap^jlication to the hon. sec., Mr. J. G. 
Bradbury, 1, Hogarth Hill, Finchley Road, N.W.4. 

Liverpool Photographic Association. — It is not perhaps- 
generally realised that the Liverpool Amateur Photographic Asso- 
ciation, which is now holding its annual exhibition of members' 
woi'k at its rooms, 9, Eberle Street, Dale Street, is the oldest photo- 
graphic society in the world, having been founded in 1853, and 
ante-dating the Royal Photographic Society by a few months. The 
first photographic journal to'be published was the official record 
of the Livei-pool Association, and so- imipoiltamt and wide-spreading 
became its influence that its offices were moved to London, where it. 
exists to-day as The British Journal of Photogr.^phy. 

Royal Institution. — A general meeting of the members of the 
Royal Institution was held on Febi-uary 4, Sir James Crichton- 
Browne, J.P., F.R.S., treasurer, in the chair. Mr. J. Turner Max;- 
Gregor-Morris and Professor PaAile Popovic were elected merabera. 
The secretary announced the decease of Sir John Wolfe Barry, 
member of the Royal Institution, and a resolution of condolence 
with the relatives was passed. The managers reported tliat Dr. 
Mond, under the conveyance and deed of trust of the Davy Faraday 
Research Laboratory of the Royal Institution, covenanted to pay . 
to the Royal Institution before the year 1926 the sum of £62,000 as 
endowment fund. The trustees have in the most generous way anti- 
cipated the obligation by eight years, and have transferred the sum 
of £66,500 in 5 per Cent. War Stock to tihe trustees, nominated by 
the managers, of the Davy Faraday Research Laboratory Endow- 
ment Fund. This will add matei-ially to the income available for 
the purpose of promoting and mainitaining the efficiency of the Davy- 
Faraday Reseai'ch Laboratory in the advancement of original 
research in chemical and physical science. 

Deaths from Process Acid. — A remarkable accident, in which 
two men lost their lives through the brealiing of a carboy of nitric 
acid, occurred at the Andre Sleigh and Anglo Engraving Company's 
premises, Milford Lane, Strand, last week. The carboy was found 
to be cracked, and the acid was running over the floor in the neigh- 
bourhood of the gas-meter. Dense fumes were rising, but in spite 
of this Mr. W. A. Stevens, the assistant general manager, Mr. Wil- 
liam Beer, the storekeeper, and Mr. Wise, the works manager, 
pluckily took steps to prevent the acid reaching the meter, which: 
anight have caused a disastrous explosion. Having stopped the risk 
of this danger, they resumed their ordinary work, feeling no ill 



Ft»bru»o 3. XSiai 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



71 



effccU. An hour or ao latw Mr. Stevens and Mr. Beer became ill. 

-' - --' iwith died on Saturday. " It is a moal unusual 

i Hunter, the nianaging director of the firm, 

■ipnir repreeentative. ' During twenty yeara' cxperi- 

.n-aphic work I have h.i.i .-s.veral similar accidents with 

'^en none the worse. It is possible that the acid 

with a line dustbin or come otfaar metal, which 

:<ril u to give off deadly fumes." 



Correspondence. 

• — ■ 

. * Corr»tpomdtnU sAomU mmw write on both »id— of lh» popsr. No 
notiea i§ takmt of eoi mmm i f a ti ows unlesa Ih* namtt emd addrtuM 
•f tht writert or* giren. 
'.' H'« do not unJertaks ropoiutMii/i/ for iht opMtons txpr n ttdht 
uur eorrtfjxmd nil. 

DEVELOPER POISONING. 
To the Editors. 

GentlMoeo, — I hare soflercd from this for ]r«M>, and have tried 

remedy fincludini; the one* which have appaared in the 

from time to timet, with no rrsult. 

]\..inf an oinUneot for rheum - in the booae, I thought 

1 A . Kil try it. and was deli.{ht- ' . to find the huge gashes 

I aiwl aim >in. In three day< 

adid oiuii <ang lady bromide 

.t Methyl. Salicyl. 

15 ; Lanoline Hyd 

..•r,ii. ij. il_».u i .; work and after- 

v<asb hands in imft le them in dilute 

■ id. 1 can »> ' '.ister which 1 

id in «••• for .n is one well 

ire fur riuu m a l i c paius. — I am, yours 

C. M. FoanK. 



> vu-w PATENTS AND DESIGNS BILL. 

To Um Editors. 

• \ !: ' as abore has : --n introduced into 

: • >iis. On.- f.f it -t,« is to improve 

• • •• present - Act which 

t . '"'fking in < nventions. It 

reforr, more particularty oi interart to the manufacturing 

of tli« principal faatucs of the atm Bill are very briefly 

I t.> Ix^lr.w. 

! any peraoa iatemt>'d may at any time present 
■ t)i:>t tht> fnon<iix,'\ riirhta have been abused in 

(being ana capable of 
.; worked hera on a com- 

... '"" b« given for non- 

haa not baen ' rk tha invention on 

.. ,-.t.i..,n nitt;. . ....j.^umed for a period 

•nc 

' -■ invention here ia baiog 

'- >-i^a ia not baing mat 

int a lioence upon 

r the establishment 

XIII it ia in tha public 

condition* attached 

' • nn are proved, 
: ">wers : — 

I .r:i<'.| nith UlS WOrds, 

' ). If this is done, ever}' 
'Oder hu licence (or one 
inner as if the patent had 



been so endorsed at the patentee's request. Such an order may be 
made notwith.standing that ther« may be an agreement subsisting 
which would have precluded such endorsement at the patentee's 
request. 

(b) He may orler the grant to the petitioner of a licence on 
certain terms. The patentee may be called upon to take steips to 
prevent infringement, and if he refuses or neglects to do so within 
a month the licensee may institute the proceedings, making the 
patentee a defendant. 

(c) If the Comptroller is satisfied that the invention is not being 
worked on a commercial scale here, and cannot be so worked with- 
out capital, for the raising of which it will be necessary to rely on 
the patent monopoly, he may, unless the patentee or those claiming 
under him will undertake to find such capital, order the grant to 
the petitioner or any other person able and willing to provide such 
capital of an exclusive licence, suhject to certain provisions. 

(d) He may revoke the patent either forthwith or after a reason- 
able interval, unless in the meantime such conditions as he may 
prescribe, with a view to preventing the abuse of monopoly rights, 
are fulfilled. 

(e) He may decide to refuse the application. 

The granting of an exclusive licence may be made conditional 
upon the licensee giving proper compensation for any money or 
labour expended by the patentee or any existing licensee in de- 
veloping or exploiting the invention. 

" Ljcencks of Right."' 
The salient features of " licences of right " (which are new to 
patent legislation) are briefly as follows : — If the patentee so re- 
qneata, the Comptroller. shall endorse the patent with the words, 
" licences of right," if satisfied that the patentee is not precluded 
by contract from making the request, and thereupon : — 

(a) Any person shall at any time be entitled, as of right, to a 
licence upon such terms as, in default of agreement, the Comp- 
troller may settle. 

(b) In settling the terms the Comptroller shall be guided by the 
following considerations : — 

(i| He shall, on the one hand, endeavour to secure to the 
pit'iitee the maximum advantage consistent with the invention 
l..iiig worked by the licensee at a reasonable profit hore. 

(li) He shall, on the other hand, endeavour to secure the widest 
possible user of the inventbn here consistent with the patentee 
deriving a reasonable advantage from hie patqHt righta. 

(iii) He shall also endeavour to aecure equality of advantage 
among the seTeral licensees, and for this purpose may, if he con- 
siders it advisable to do so, reduce the royalties or other pay- 
ments accruing to the patentee under any licence previously 
granted. 
In considering the question of equality of advantage, account 
is to be taken of any work done or outlay incurred by any pre- 
vious licensee with a view to testing the commercial value of the 
invention, or to securing its woricing on a commercial scale here. 

(c) The licensee may prohibit importation of the goods. 

(d) Every licensee shall be entitled to call upon a patentee to 
take proceedings to prevent infringement, and if the patentee 
refuses or neglects to do so within a month, the licensee may insti- 
tute such proceedings in his own name, making the patentee a 
defendant. 

(e) If the infringing defendant is prepared to take a licence upon 
terms to be settled by the Comptroller, no injunction shall be 
awarded, and the amount of damages (if any) shall not exceed 
itjljjjJ0jtm amount which would have been recoverable against him 
aa lieaMMAf the licence had been dated prior to the earliest in- 
frfn^cnrtnt. 

This paragraph shall not apply where the infringement consists 
of the importation of infringing goods. 

(f) Renewal fees on a patent so endorsed shall be one moiety only 
of the fees othentise payable. 

All such endorsements are to be published for the purpose of 
bringing the invention to the notice of manufacturers. 

If no licence exists the C<»pptroller may, on the application of 
the patentee, and of payment by him of the unpaid moiety of re- 
newal fees which have become due since such endorsement, cancel 
the endorsement, whereupon the patentee's rights and liabilities 
shall be as before endorsement. 



72 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[February 8, 1918. 



In future patents for articles or substances prepared or produced 
by chemical processes, or intended for food or for medicinal or 
surgical purposes, no claim shall be made for the product, sub- 
stance, or article itself, but only for the special methods or pro- 
cesses of manufacture. In case of any patent for an invention in- 
tended for or capable of being used for the production of food or 
medicine or surgical appliances, the Comptroller shall, unless he 
sees good reasons to the contrary, grant to any applicant a licence 
limited to the use of the patented method or process, and with a 
view to making the food, medicine, or surgical appliance available 
for the public at the lowest possible price, the royalty or other 
consideration shall be fixed at such an amount as will secure to 
the patentee the minimum profit consistent with his deriving a 
reasonable advantage from his patent rights. — Yours faithfully, 

H. T. P. Gee, Associate I.E.E., 
Patent Agent. 

25, Victoria Sticeet, S.W.I, and 70, George Street, Croydon. 



Jlnsioers ro Corresponaents* 

— • — 

BPBCXAL NCnCB. 

In toiuegvenee of general reduced luppliet of pa per, at the retnlt 
of prohibition of the importation of much toood pulp and frail, 
a imaller ipace will he avaUahle untU further notite for repliei 
to eorreipondenti. 

Moreover, we uiill aniwer hy poit if itamped and add ruied enve- 
lope M tneloitd for reply i 6-eenl International Boupon, from 
readeri abroad. v/ 

Whe f%M queitioni and aniweri will be printed only in the tote of 
inquirie* of feneral intereet. 

Queriei to be amwered in the Friday'! " Journal " muii reach ut 
n»t later than Tuetday (potted Monday), and ihould he 
addretied to the Bditort. 

Lens. — Both are lenses of the highest grade, but neither is specially 
a portrait lens. 130 mm. is the focal length — in English measure 
5^ inches. 

A. G. B. — We certainly think that the Howellite inverted mantle is 
worth while putting in in place of any upright pattern that we 
have used. If you get the Howellite burner itself from GriflSn'vS, 
we sihould say that any decent tinsmith could fix it suitably upon 
the ordinary lantern tray. 

Pitch for Fixing Dishes — Should plain pitch, run in the joints 
of a wood box, used for fixing bromide prints, have any in- 
jurious effect on them? — CoEious. 

We should prefer not to use it if it could be avoided. Any 
hurt it may do will be simply mechanical in the way of dirtying 
the prints, but usuaUy such wooden fixing dishes are best made 
with good rivetted joints which require only a little white lead to 
make them watertigiht. 

Aspect of Studio. — WiH you kindly give me your opinion wilidoh 
would be the best aspect for building a studio — a somewihat 
obstructed north Hght, or a more open due east light ? Should I 
be troubled with the sun in latter case? — Lex. 

It is impossible to say which would be the best aspect witliout 
knowing the nature of the obstruction on the north side. The 
sun might give trouble in the east ligiht, but you could overcome 
that by having thin white blinds all over the roof to out off the 
direct rays, using the dark ones as usual. 

D. W. J. — The method of using the autograph camera is to write 
the name of the subject on the strip of film which is disclosed 
imdemeath through the slot on the camera back with the stylus 
provided, and then to hold up the slot to bright light for a 
second or two. You should write to the Kodak Co., Kingsway, 
London, W.C.2, for a circular which will tell you all about the 
autograph back. A very good book on photog;rapl>j- for begin- 
ners is one by F. T. Beeson and A. Williams, published by 
Messrs. Nelson at Is. Any bookseller oould get it for you. 



Washing Cabd Strips. — ^Could you oblige me witli name and' 
address of makers of a washer suitable for washing postcards iw 
strip (six on), requiring no attenltion, that could be used in an 
ordinary (bathroom) bath, or suggestion of a reliable method of 
washing strips? — M. B. 

We do not know of any appliance specially designed for this- 
purpose other than the floating clips used for washing 
films. Strips of card can be treated like roll film. Fix 
a Jaynay clip at each end of the atrip and then put into the bath. 
If necessary, the strip can 'be lightly weighted to keep it under 
tlie water. 
Blacking Tinfoil. — Can you, through " Answers to Correspondents," 
tell me of a method for ■chemically staining tinfoil black? I have 
a 3 iby 1 ebonite tray for use on the stage of microscope when 
looking over for animiferous material. This I wish to coat (or 
cover) with tinfoil on account of electrical •disturbance, but the 
tinfoil must be black. If you can help me, I shall be grate- 
ful.— G. T. H. 

We cannot suggest any reliable chemical method of blackening 
tinfoil, and would consider your best course to be to coat it with 
a good dead black, such as the Vanguard Company's Nigrogene. 
Pastel Colouhing. — I am anxious to take up pastel colouring on 
bromide basis, but cannot get the crayon or pastel to adhere in 
any body to the print. The colours will only bite on the- 
bromide surface in very faint tints, not sufficient to cover up the 
photographic look of the picture. I have tried several grades of 
bromide paper, including a nice eggshell surfaced cream crayon, 
which is a very suitable colour for this class of work. — T. A. 

As far a£ we know, no method of making pUstels adhere to 
the surface of bromide enlargements to the extent you require 
has been published, but we have found it to be a good plan to 
thoroughly damp the surface of the print, blot off all superflnon* 
water, and then to apply pumice powder all over the surface with 
a large camel-hair brush. The print is allowed to dry and the 
surplus powder dusted off. By this means you can work even ott 
glossy papers. If this is not sufficient, you might try washing 
the damp print with diluted Higgins' mountant and dusting on 
a coarser pumice powder, such as you buy at the oilshops. This 
should give enough tooth for anything. 



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THE BRITISH 



JOURIAL OF PHOTOGEAPHT, 



No. 3015. Vol. LXV. 



FRIDAY, FEBRUARY 15, 1918. 



Pbice Twopence. 



Contents. 



KtCAtUMD*^ 

DtamMtM or PimMAnmea at 
moTootLArmK Pmijtn 74 

CoTBBDIa POVBA AMD iLLtMIs 

tTi»i Powcmar L«»«*: Tr-T- 
»»u PumroantMcn, B; 0^r«J. 

boni« l'ip«r 

BciKimrfO Dsiiov ix OrriCAl. Pio- 
JtCTMa.-in. B J J. A. Omit* 

AVALZ'-TA 



n 



T& 



I>« •III '>r Lavt. B. J.Omrn. 



U. 



PlUK 

FoarBcomiiu EuMiTiom to 

ItKBTiifM or BoasTin ao 

» ■' ■ U 

K : — 



ot H)rpo— Dtfalopcr PotMa- 

lot PiM*aiM» 



u 



" kiinuuucp tht? (imUi on •ctivK crrTice o( • 

"!•" • ■ ■ :Mg aUff. (P. 80.) 

■i utd ooaehidiiia forttoa of tit* Mtiole bv Mr. Omiee 
<»' -iflciKn in optioaT proieetion the aathcr deaia with the 

cinvii'.j.Uj^r^ph ehiitter m reiatioo to the ' Imcumm the 

ailvantaKv* unit ilnadvantagee o( •lt«m»ti\- (P. 78.) 

In • le«dinK article we g" reaaon- 

•blv )>e called " permanence - degree 

n' ]>'Tm*aaiirm in any mm pn.»-«i» mjun irom tjie *nmnusi\y per- 

>"->' t rarboB and pta^mn print) i« largaljr oooditioned by the 

r-M- aiid asperienre eiemieed in ita working. (P. 74.) 

Thr m->nur^'t>ir>'r< <.i <lr> plate* liave anDOoaeMi a forther inrreue 
in lb«? pno»* of j>iat.-« i i' 81. ( 

The allied qoaMion o/ ooreriae puwv and illnmioating power ul 
Viaee reoaally dealt witii l>y Mr CrahAm M. Nicol is (urlhcr 
rnlaraed upon in iuller d<-' r. Welboma Piper, who 

draerlDe* a roethod at testin. -nt-ra. (P. 76.) 

The a»<" of r "-dwrr li-m U. ii invpetiated by two German 

espenmentr-r mrorixl vrv -a<.ia aoTationa ot iodinr (ol- 

townl liy hypo m prxffniaoe to (he io.l . t.- rvducer. (P. 82.1 

K.\p<-nn>cnt* on pcaribb iMWarator* ive op to the pre- 

i«-nl yir! IH no nrioJIaL (P. 74.) 

I'r).:<'r'i.:t . I. t)ie temperature of all •olutioaa ia better obtained 
b.v keeping Uic iltrk-room at a oooatant t«inp«*tiire, and i* a atfc- 
guaid igitiial ftWiiHi any ooa of tbetn t<Ki warm. (P. 74.) 

The annual gmerai Biaating of tbe V- .i1 Photographic Society 



took 

Pr, 



.!,■ 



tl. 

w«»- 



•n Tneeday laat.'when I 
nteetmkn to Mr. John I' 
that may help to n 
"••pinif (foalit'^* of ■■' ' 



photographic indimtr 
< M the I9t7 tmdc .>- 
'I of a n*w tecretary 
■A plao* of the late M. 

I I 

•.^r for i,Vfm*it\\t\. 



iiie .r 



thv itmt, reauil* are to be obtaineti. 
J»ag» 74 



"^wan waa cleotetl 

IV 80.) 

tunally oon- 
ti page 73. 
•f a preecrip 
bject of cor- 

I Oermanv, it ia announced 

'"d «ti«factory. (P. 79. 1 

■<T to the Photographic 

... Bridge took plMe laat 

/raaabU odoor aaaocialed 

■ xure on line eobjecta, if 
••mphaaiaed in a note on 

meeting of the Rdntgen 



£X CATHEDRA. 
The Royal The chief items disclosed in the baksce- 

sSci*e°t''*''*''*' *^*^*' *^^'''* ""^^ presented to members 
at the annual general meeting of ike 
Society on Tuesday evening last were those relating to the 
exhibition. The latter, it will be remembered, was held 
la»t autumn at the Society's house in Russell Square in- 
stead of at th» Suffolk Street Galleries. Thus, the rent of 
the latter, £105, had to be paid without the compensations 
in the way of admi.ssion money and charges for wall space, 
which the venue in the West-end afford— to the amount ef 
£200 in round figures. However, on the President's initia- 
tive, a " whip round " among the members resulted in the 
collection of aspecial fund of over £220, so that the extra- 
ordinary liabilities of the time have been more than met 
and the exhibition saved from having been a heavy 
charge upon the general finances of the Society. That such 
a course ia eminently desirable is clear from the increased 
costs of printing to which the Society, like any concern 
which publishes a journal, finds itself committed Never- 
theless, it will be a matter for the consideration of the new 
President and Council whether this is a policy which it is 
re<-|uisite or desirable to repeat a second time. 



Durable 
Amidol. 



One of the few disadvantages connected 
with the use of the amidol developer is 
the short time which the developer remains in good working 
condition. The following hints may help to minimise this 
trouble. It is usually recommended to make the solution 
of working strength, but this is a mistake. Tf the developer 
is made with half or even a fourth the normal amount of 
water, it will keep much better; it should be diluted to 
normal strength as required. The water used to dissolve 
the sulphite should be well boiled and allowed to cool a little 
before adding the sulphite, the amidol being added when 
the solution has cooled to normal temperature. Tliere 
is no advantage in making stock solution of sulphite 
and adding the amidol in small quantities as required 
except that the surplus may be thrown away. The mixe<l 
devaia^er^rill keep in working condition longer than the 
plain suTphite solution does. Tlie keeping qualities of this 
developer are much improved by the addition of a little 
potassium metabisulphite; say, one drachm to forty ounces 
of normal strengtli solution. There is a considerable differ- 
ence in the quality of amidol as now sold. The best keeping 
samples are in bright metallic-looking crystals, which pour 
fr«>ely from the bottle and give an almost clear solution. 
Other samples, which work well when freshly mixe<l, are 
duller in appearance, and cling together as if damp. The 
solution is dark and turbid when mixed, but clear if 
allowed to stand : the solution does not keep so long unused 
nor does it yield so many prints before becoming exhausted. 



74 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[February 15, 1918. 



A Wapm We recently commented on the fact 

Dapk Room. that operators, when compelled to 
warm a developer, frequently overdo it, and so spoil the 
negatives. It is, in fact, a not exactly easy, and generally 
very troublesome, operation to warm up a developer to 
just the right temperature, while the developer is not 
the only solution that works badly when cold. In prac- 
tice it is far better to give up attempts to get individual 
solutions to A uniform standard temperature, and instead 
to adopt some method of warming the whole room. This 
can be done without much diflSculty nowadays, as 
numerous types of gas stoves, gas radiators, hot-water 
radiators, etc., are available, and the cost of running, 
which need not be great, should easily be balanced by 
the efficiency gained in working details. The advantage 
of keeping the room temperature constant is that all the 
solutions which are stored in bottles, or in use, also keep 
constant, the one thing not affected being the tap water. 
This one defect is easily got over by keeping a supply of 
water, especially for mixing with solutions, also stored 
in the room. We use a large stoneware barrel or crock 
fitted with a tap, and so cold water from the main need 
not be used at all except for washing purposes. The 
exact temperature of all the stored solutions is recorded 
by a thermometer kept permanently in a bottle of water, 
and 80 long as this bottle shows a fair mean temperature 
we know that our solutions and water supply are also all 

right for use. 

« * « 

Exposing The ideal negative of a black-and-white 

on Line line subject should, of course, show 

Subjects. quite transparent lines on a per- 

fectly opaque ground, but these conditions seldom 
exist in the developed plate, and have to be arrived 
at by after-processes of reduction and intensification. As 
a rule it ia impossible to avoid a certain amount of veil- 
ing or fog over the lines, and so a reducing or " cutting " 
solution is always necessary, but if the background is not 
black enough at the start it stands a chance of being so 
much further reduced by the cutting solution as to 
render it difiicult to get enough opacity, even with a 
powerful intensifier. The best initial negative can only 
be secured by taking pains over the exposure. If the 
time is either too short or too long it is impossible to 
develop up to blackness, while, in the event of the time 
being too long, additional veil is thrown over the lines. 
The exposure must, therefore, be rather nicely adjusted, 
and at the first attempt it generally pays to make a trial 
set of exposures in strips. It must, however, also be 
remembered that we cannot get full contrast in the nega- 
tive unless it exists in the original, and a black-and-white 
drawing will not show this full contrast unless it is 
sufliciently well illuminated. If the light is too dim the 
drawing will not really be black and white at all, but 
black and grey, and it will photograph as such, showing 
transparent lines on a grey ground, instead of a black 
opaque one. Good light is essential for this kind of work, 
and, given brilliant lighting and a correctly-adjusted 
exposure, it is quite possible to get a jet black ground 
that will need no intensification. 

* « « 

Reclaiming Since the speculative note of last week 

Hypo. -we have made a ifew exiperimients with 

possible "regenerators" of hypo. The use of sulphide 
was looked upon as unpractical, as it was obvious that a 
bath containing sulphide wwild be a very undesiira,ble 
;fixer, even if it, would work at all. All tie same, we tried 
it. The chief predpiten-ts tested were aluminium, zinic, 
copper, and mercury. The first proved useless at once, as it 
rapidly deoompioe^d the hypo, setting free sulphuretted 



hydrogen and bringing down sulphur. Zinc, whether 
pure or impure, had much the same effect, but acted more 
slowly. With copper the metal was soon plated with a 
kcse coating of silver, while the solution remained quite 
clear and apparently unaffected. With mercury an 
amalg'am of silver was formed, the solution remaining 
cJliear. In ,one settaf testis twenty-two quarter -plates were 
fixed out in 8 ozs. of 20 per cent, hypo, the result being 
that the time of fixation was increased in the priopoirtion 
lof 5 to 3, w^le in 'another set 1 gnain lof silver bromide 
was dissolved in every ounce of 20 per cent, hypo, this 
addition i*aJsing the 'fixing time in the ratio 'Oif ,8 to 3. 
•The results iwere entirely negative. No method of treat- 
iment in any way increased tbe rate ;of fixing, and so it 
became evident that the amount of active typo present 
Tvas not altered in any way. ,In cases where pure silver 
alone is abstraet'ed it seems that it is probably replaced 
■hj the metal used, while when .silver 'sulphide is formed 
the hypo itself is changed to another compound. Inci- 
dentally it was ehown 'that zinc and, above all, aluminium 
were rooSt unsuitable metals to he brought into contadt 
witih hypo. The 'userS of zinc ,developing tanis will be 
wise to aVoid developing and fixing in the B/Eime tank. 



DEGKEES OF PERMANENCE IN PHOTOGEAPHIC 
PRINTS. 

In these days when processes which yield prints of un- 
questioned permanence suoli as carbon and platinum form 
only a small proportion of the immense output of photo- 
graphs of various kinds, and when also many different 
methods of toning prints by other processes are adopted, 
the question of permanency is one which has an interest 
for every photographer, 'and is, morever, one of which a 
photographer who sells his work needs to have some fairly 
comprehensive knowledge. It may therefore be of interest 
to review the question from the point of view not only of 
making prints of the utmost permanence, but also from 
that of satisfying customers as to the quality of prints in 
this respect. In this inquiry it is desirable at the start to 
obtain some more adequate definition of permanence than 
its dictionary meaning of " oontinuanoe in the same state 
or without any change which destroys form or character." 
The dictionary definition does not help us very much. 
Another which has been proposed is that a permanent 
photograph is one the image on which will last as long as 
the paper which supports it. This again is a definition 
which is incomplete unless certain conditions under which 
the print is kept are specified. Moreover, it is one which 
marks too high a standard of permanence. Paper, if of 
the reasonably good quality which is used for the prepara- 
tion of photographic printing materials, may reasonably 
be relied upon to last for a very long term of years. In 
the case of paper of such liigh quality as is employed in the 
making of platinum prints its period of life may be of the 
order of hundreds of years, and would thus make great 
demands on the stability of the image. True, a black 
platinum print possesses an image which is so unalterable 
that it rivals its paper-support in permanence, and justifies 
the remark of Mr. Chapman Jones (in " Photography of 
To-Day,'' p. 196) that " there seems every reason to sup- 
pose that if platinum prints had been made in Abraham's 
tinie, or when Egypt was at the height of its glory, they 
might, if preserved with reasonable care, have been avail- 
able for our information at the present day." Unfor- 
tunately such considerations as these will lead us nowhere 
in the direction of providing a definition of permanence in 
photographs such as can be adopted for practical purposes 
under present-day conditions. We think that such a 
definition is to be found only in some formula representing 



fc'coniikry i'') la'o J 



THE BRITISH JOURNAL OF PflOrOGRAPHY. 



75 



in 
»•< 
W 

a 

int-"---=t to »mat«ur 
SI' i«aliag » 

which re-^ - 
wr: I be t«rnt«d 



len permanence. Opinions will 

^•i is ttkAt DO marked alteratdou will 

'■vben kept under r<ia»oual>Ie oondi- 

-.. ^i, say, twenty years. We are now 

belonging to thv< vast majofity which 

.= portraite. view*, etc. Ooviously 

inuoh too short a time for prints 



rime desi 
or fifty 
;' Ruoh a defii: 
^xpk>r<» piirt' 



such prints 
lirad yearo. 
'. irovidea 
ti mtt in 
loots of 
- profes- 



touched on i> that of 

•ro- 

oe^' . ^, uiu piiraae js (or wm; unuorauwa ... ... ..;;^r)- 

•pvvM 11. In regard to thia it may be said that up to within 
ten rrr fifteeo yean ago a photograph by a " permanent 



penrxoent " photou' 
thia phraae is (or was) undoratood 



meant one by either the platunim or carbon pro- 

' Tr^'Te it a very good wson why it had this tigoiooa- 

' 'luring toe twenty-five or thiHy y<*n daring 

I meoiaed f>ap«r wa ' ? method in ani- 

earbon and platn. ' >*rp the ooty two 

ui photograph wfaacfa oowid U have entab- 

■I tbe iin e i vss in the wtesn of t' . a<: vi<>{din<.' 

-^ of nnqoertiooad permMMOoe, an>i 

iUtin^uiahed from Uie ordinary aii , 

fiartimU t^r yean, to fade. 

:! ysars aji- ., ...u.d r»-"^'"«'-''^- '— -^ 
(Joart sense a pemiai: 

for the P-»rty to i 

«-■ ■ terpreiaitioo oi me \«nr. ;u ;nr ir»«ir 

a lirnmitfo and other pnnting p*|Mn ha» dose a 

^- tarh that povtioa, ^nd li u very doubt • 

w n " pertnaneat pbotofnwph " now has :. 

mn notes oo the d igiw of pemMBMtce 
t is iu'portant to draw dis>i net ions 

'•!» luMi* of 'iiKfle tDfrirnvrit which 
t< a 

I. i . the 



ton 



tl 
it 



Thu* 

1 'hat 
in 



iij" 



:ts prodoead 

v«i*uiit.:4400 MtWMO 



I' 

Hii- 



1)11 li. 



the gre 
- — • > iters is a 
'lid be s**y to claim «x< 

' r nrinla on ike rtnogth of on* or 

"«o aad good aftar twwity j^aars. 

tiie p^eoUAl aiAerenoa baUree i i tiie admiMedly per- 

■tft " j,m '*m> m % (carbon Mid platioaa) is that with 

>f difficulty, alrivxt of inpoamfaiUty, to 

.ire not prmian'-nt. whereas in tha cm* 

I oirt ail othsr prinltBg proc««-«a tfM J s«t»> of pv- 

r.'^ I* largelT ooBditMDM by the euv ana SK] 

iMud in wondng the 

t V of * r»rnf'<"% »' 



I tlM proctmtK. aad thus the real 
• ra^ aw i parmansaea aoat be judged 
f thanniltt oblaioad with it, and 
>«» which may he tba rwult of care and 
•^an would not mreiva under ordinary 

•T-t-nai 'Tin'iituins. " 

ving now oarbon and' platinum eoi of eoiwderation, 

'■e DO doubt that the mmt psrmanapt form of 

. among the papats available ai Iha prassBt time 

« broouda or faaUfht |Miper. Such a print, if 

i/)m and moni^ad and p ii ^e n ra d under tuitable 

I Id amply falfil !>:t<->i a requirvmaBt, aa 

lence, of twenty y-ir*' life. Th» eCact of 

pnn It. when it i> aounted ari'i framed, should oevwr 

" ^han a 'lii^ht yellowing of !h" whi(«>. aii<I hmmI not 

he that. Ity <>xfM>'>.ijr>- '" the -m- 

'XB gas or stove* cufh |>r ;.t- are ......^ ... <.i,..tnt. 



Ml tile (-uiirse of tnnt*. i liroiixed or semi-metallic deposit, 
i-hietly 111 the shadows, whuh if a certain di«figui«Ba«ut, but 
not one which oould be rra^onably called impermaaenoe. 
The same effect ia to be noticed when prints on these papers 
remain in contact with ordinary printing paper as they do 
when inserted in books. .Such action appears to be due to 
matter in the paper with which the photograph is in oon- 
tact, and plenty of evidence as to the regularity of the 
effect is to be found in tlie prints which formerly, from 
about the year 1887, were inserted iu the " B.J. 
Almanac." In some oases thii bronzing or aolarisation has 
reached a point at which it is a marked disfigurement : in 
other cases it is accompanied by pronounced yellowing of 
the whites. 

A sulphide-toned bromide, however, is less liable to tlu!i 
bronzing, and for the very plain reason that the bronzin<; 
14 i. i.pecies of slow <iii'i>1i'.!i>ii' nytl, if tlie sulphidiug pro- 
cess ia carried out tlf > toning, there cannot be 
the opportunity for 'il^r appearance in pro- 
cess of time. In t - • ibtedly sepia ' print* • 
mada by tha bleach ano suj{iiiid<« iirooess are superior t4> 
those yielded by hypo-alum and similar toning procease* ' 
in whi< " ■ " i.Hion is not carried to a point of 
ootnplc: vaking. «epia bromides, by either 
procew. iitAy -be oou>Hi«red aa of a higher degree of per- 
n-an«nr<< than the untreated black-and-white printo. We 
k that the same can be said of the warm -toned 
!i of late year* have oocna rather more into use 
and are produced by treating the sulphide-toned printr. 
wit>i n cold U>ning iMth Attraotrve as these effect* are, 
Wr 'Te ii evidriKo to shew that they are somewhat 
•J.- to change liv f-—--'-.- »■■ ''■'>-• T'-" ■•''ange is 
«aaie year* ago ••• s' oon- 
>i.>ii' « ' to ordinars' <iayiignt. w*b n<iT^-.inv to pro- 
duce a change— but 'the Liability does 'certainly 

< i<. U{ ciUier toning proceaas which, before the sulphide 
-tbod baoUB* popular, ware hu^galy employed, it is not 
MMatbls to tpeak in the tame tanas as of 
Prinfci tnned with rnff^^r or tiraaium are e\ 'c 

to • fa year or tw t. 

br<. ^-iirements wli ••■*' 

Kuch that the purrh*>'»>r of a print woi ■ly 

ol>>'<'' '■• fill'- i.»t.«.r . ■ . •• i>f iiniitu t<' " , ;•<" ■< 

ta ' ' us in expreesing a |iosi- 

,„,,, ,,ui ■■'•fA them ill ■ . ■ti-.'<M'v 

■•re between tho». "I ami tl •■'I 

i>y one or other of the {inK-oBM^ j>i-i iiienticjn*'"! 

'Coming to what are somatimes railed even nowadays 
" silver " prints, tho»e on ordinary P.O.P reouire to be 
placed in a lower clawi a* regards permanence than black 
and-whiia bromidefi They are appropriatetv so classed 
whan lonad by the brat method, namely, tne use of a 
•eparaU gold bath follow Altliough in theory 

tha use of a combined U>> ' tig bath should yield 

print* whirh aro )ii*t aa parmanaot as tltoae separataly 
toned ajid fixed, thrr.- ,-au be no doubt that P.O. P. printti 
by the combined ni" J>tty rank still a little lower 

In xqgVS^o those U, ■■-.lii platinum, a process which 

dewrvedly ha* now largely gone out of use. Uie results were 
often of a very low degree of permanence indeed : ap- 
parently the use of any platinum toning Itaiii on a gelatine 
paper yields results which cannot lie de}>ended upen for 
parmaneoM. Tba other \ariety of silver printing paper. 
%-ii., »»•' may, w l>e broadly classed, with- 

out inj it, witli Its obtained on ordinary 

P.O. P. bv the combined bath. Ilere experianaa is tone- 
wbat ooamotang : probably for tha reason that self-toning 
papan, being chiefly used by amateurs, are not always 
handled under the best conditions for working which papers 
secure in profesMonal ratablishniants. Still, we think that 
general experience i.< to tha affect that their permanence 



76 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[February 15, 1918. 



is a little inferior to that of P.O. P. toned in the separate 
bath. A distinction must also be drawn between gelatine 
and oollodion self -toning papers ; there seems no doubt that 
those of the latter clase are superior to those of the former 
in stability. Of the remaining type of silver printing 
pai)er, namely, collodio-chloride or C.C., tliore is greater 
divergence in the matter of permanence than in the case 
of perhaps any other paper. The impermanenoe in this 
case takes the fonn not usually of general fading or yellow- 
ing, but that of the appearance of spots often within a very 
short time of the prints having been made. Worked under 
the best conditions and with tlie fullest knowledge of the 
precautions which are needed in its manipulation, C.C. 
paper is no doubt capable of yielding prints which are the 
equal, if not the superior, of those on ordinary P.O. P. 
toned by the separate bath. But in lees skilled hands its 
results have often proved to be positively fugitive, a chief 
cause no doubt being the necessity of removing all traces 
of the acid platinum toning bath, before the prints are 
passed on to fixing. 

In concluding these notes we should revert for a moment 
to the platinum printing process of which we have spoken 
above as though its results were invariably of the very 
highest degree of permanence. An exception to this 
general statement needs to be mentioned. While nothing 
in the way of a photographic image is more permanent 
than that of a black platinum print, the same cannot be 
said of all platinum prints of sepia colour. Methods of 
introducing a greater or less degree of warmth by additions 
of mercury, etc., to the developing bath when using the" 



black paper almost all of them represent a sacrifice of 
undoubted permanence to pleasing appearance. Also, we 
think it may be accepted as true that for really permanent 
sepia results on the papers especially manufactured for this 
effect hot development is an essential factor. Such is the 
.<riethod adopted for the sepda paper of the Platinotype 
Company, and both chemical tests and those of time fUlly 
prove that the results are permanent. Equally we have in 
our possession plenty of examples of sepia platinum prints 
in the making of which the method adopted has been that 
of cold development on papers manufactured for use ac- 
cording to this system : they show the pronounced fading 
which is the result of ordinary exposure in moderately 
lighted rooms over a period of years which is not more 
(than ten at the outside. Palladiotype prints, recently come 
into use as the result of the restriction on platinum, pre- 
sumably are just as permanent as those by the ordinary 
platinum process. This is only an inference from the 
known properties of palladium metal, but it is no doubt 
one which experience, as time goes on, of palladiotype 
prints will confirm. We have not referred to oil or Bromoil 
prints or those transfer effects obtained by taking impres- 
sions from these latter. Obviously such prints possess 
exactly the permanence of the inks which are used for pig- 
menting. There is no reason whatever why. these inks 
should not be fully permanent, and therefore such prints, 
both from the nature of the pigment which forms the 
image and from that cf the medium which hold it, deserve 
to rank as fully the equal as regards permanence of those 
by any process. 



COVERING POWER AND ILLUMINATING POWER OF 
LENSES: TESTS AND PERFORMANCE. 



A KECENT article by Mr. Graham M. Nicol, on the covering 
power of lenses, raises some points with regard to lenses that 
are certainly not generally understood, though their practical 
importance is very great, and some of these points are well 
worth more detailed consideration. The first to demand 
special attention is the distinction between covering power and 
illumiinating power. The best way to realise this is to take an 
ordinary quarter-plate B.R. lens and fix it up temporarily on 
the front of a large camera, 12 by 10, if available. First of all, 
open the lens out to its biggest stop aperture, and secure 
approximately sharp focus on the screen on any object at a 
reasonable distance, say 20 ft. away. Now remove the focuss- 
ing screen and look obliquely through the lens. At a certain 
angle it will be seen that no light is transmitted at all, the 
two sides of the visible aperture apparently closing together 
and cutting out all light. Obviously this angle must mark the 
limits of the largest possible circle of light that the lens can 
project upon the plate. Next look through the centre of the 
lens. A perfect disc of light is then seen, but as we move the 
head sideways this contracts to an ellipse. At a certain angle 
this perfect ellipse changes to an imperfect one, with pointed 
instead of rounded ends ; in fact, to the shape of the aperture 
formed by sliding two elliptical openings over one another, but 
not allowing them to coincide. This change in form is due to 
the lens mount interfering with the light Up to this point 
we smiply had an oblique view of a circle. Which is an eUipse. 
We now have an oblique view of parts of two circles which 
apparently intersect, one being the circular stop aperture and 
the other the circular lens mount. The angle at which this 
change takes place is obviously the one limiting the iUumi- 
nated di.^c which can be produced by light jiassing the full 
unobstructed stop^perture of the lens, and this circle if is 



convenient to call the circle of full illumination, while the 
other may be called the extreme circle of illumination. 

Suppose, now, we reduce the stop of the lens. It will be 
found, on trial, that the circle of full illumination has 
enlarged, though the extreme circle has not changed. If, how- 
ever, we change the R.R. for a lens of unsymmetrical con- 
struction, the extreme circle will also change : it will 
become smaller as the circle of full illumination becomes 
larger if we use the type of lens called the single landscape. 
What happens to the extreme circle is, however, of small 
moment, for in any case the illumination near its boundary is 
so faint as to be photographically of no value. In fact, it is 
almost impossible to record its limits. 

As the ellipse shown by a circle viewed obliquely is neces- 
sarily of smaller area than the ciixrle itself, it follows that 
at the margin of the circle of fuU illumination the light is 
rather less than it is at the centre. The diminution is not 
much, and as the ordinary plate has considerable latitude 
it is not beyond its capacity to render this really graduated 
disc as if it were a uniform one. If, however, we go outside 
the circle of full illumination the visible aperture is very 
rapidly and materially cut down, by' the lens mount, and 
sooner or later we reach an angle where the production of a 
uniform disc on the plate is impossible. The limits of this 
angle depend a good deal on the plate and on the exposure, 
far a plate with great latitude will permit considerable 
oveir-exjK)sure in the centre without showing it. Under- 
exposiure on any kind of plate wiU show a very small uniform 
disc, but if that plate will pemiit a considerable increase 
without spoiling the centre of the image a larger disc of uni- 
foi-mity can be produced. Leaving out the question of plate 
and exposure makes it difficult, if not impossible, to define 






Faivaaix 1^ l^JU 



THK BRIX3fiH JODBMAL OK PH0T0GBA1>U-Y. 



77 



<Itr< limiu of the iin};Io. bat seeing dtat mauj p]at«« will 
pernut ft doubling of mAaI is raftlly a correct expcMun;, with- 
MUt nhoving over-«zposure, it is cionv«niant to define the circle 
«i uniiona illimiiiafeioB aa limited by tbe angle at which the 
pviottfd vUipae miwnntjr^ the lena apertuiu is half the ana 
-eif tbu aotnpl**** circle Men centrally. Iliis angle is teemed 
the angle ot swni-illBiniitatinn, but it alumkl be understood 
that the dc&uitiua is a mom or leas conTentioaal one, pioiwhly 
iHit far from the troth in most cixeanatanoes, bat Ataaoat 
cxrtainly well away fvon it in olhen. 

An actual tcet giving varied expoeana is the only way of 
amring at the trae maxinuun limita, and if we start with 
a %vrj dtort expoaure sneb * test will be «e>y inteneting 
a>ird inatzuctive, thoogb aooMwhet oxpmam. "Om facta can 
t» lUoatisted in e li ee p «r faahion by oaing hwide paper, 
but the MBBlt «>U •MtmA bo criterion ct the sAaeti prodadble 
■•o * weB-coated negative plate, as ike bromide paper has 
BO latitode at all in comparison. It dwald be ohwmd tlut 
with nearly all laige ap srture Icoam tke ebde of Ml 
iUuBunatioa is very small ; with tnany not BBidk bigger than 
hatf-a-crown. The moat rapid snJ ^'•^•^ chms aaaati^Bata 
win prodoea aMich the big^ ctralta, tat is pmotieally all 
«asca w* nae plataa that nqair* stall bigpr rirdca to cover 
tiMNB. so the p m ctkal luaito ai« altniya ootaide that of the 
«mU of t«B illBmiBBtion and near that of smtii-illamiBattoB. 
'TUa chde ako •olargas a< the stop ia ledaoad, aad no* 
BBOoanonly we am compaUed to stop down to !.■■< tufBcMtitly 
aaiform illuminatiaa over the pUte ia osr 

It wiU be nottced that ia oonaideriag tht» . « uf illa- 

■unauon, as it atbcta the ana of a platr, we am almost 
'oidigad to bring >n the word "cov«r/' fee noae other ass^ 
to amvs. The t«rm " eoremag paw" may be naad ia this 
tat It is bmt aot so to BM it, lor ia Isbs caiar 
amaUy this exp n mi u ii dom aot imply tta lim of 
Ittm aagk or cimla that the lens wiU comr with anifacm 
i l lBBiiwH oB, tat that which it will eowr with good dsiai- 
tioB. a i till a ii matter altoyrther, aad oi^ qaite tn^rmitrrttil 
with the other. UaiortBBatrfy, thia eoneeational *^'-i^^ 
ia noc always ibs m vi d , and lo cuofmioa has arisen. Sobm 
wry gwd I mm tave very small oovering powm etmpAnd 
with thatr powm of illaminabng s plam uniionaly, aad tUa 
ma; U. no diaadvanUg*. but ii »..uld ta » somewtat awkward 
•Mtter fur a dmler to explain tu a parchaaar whom know- 
ledge of Imam was very Umitad, and *• loimm cobM hanBy 
he h l am t d it ia sach cam ta asad " eovmiag power" to 
define the rimie of good jUaminatimt An aBaaipia of each 
a leas is the Petaval p..rirAit .l.;^ii t«K(«id oa a plane ob)«c(, 
wiU show very mbsU . oa a luiUblT curved 

«6ject will show It t<t « ,rvj numifH-iwoio extant, "he fact m 
we cannot fairly t«M all kflam for mwarii^ power in tta 
same waj. Tta form of tta ubjeeft iBilaia «mm in. An 
auatixinai or lectUuMar amy, with MR jaMtook ta Imted 
on < j>Un<> sarfaca, and tta formrr wfll hmw Uttle lo Tseom- 
uMul It if it dom aot show a (■iri/laiga cknU, taiflgH' than 
any K.K. can p iod BM in tta sanh> omditioas ami mwh bigger 

Kjkwnum Kodak Cobtast or S»w ^amr.— Ia -^« ^ ^^ m la tta 
maal quarterly dividaads of I4 per aokrfj (hahig at Ita mie of 6 per 
eaaL per aanan) epoe the oalalandio(c pu i t ii i s d stock, sad of 2^ per 
emt. (being at tta tmU of 10 per cent, pm aaaam) apoa tta oet- 
•taadiBg eemsMa iloefc, tta direeton of Ita *— — r Kodak Com- 
pany of Xew Jenay tave deetared sn «tn dtvidand of 7| per emt. 
upoB Ita otmami iiack, all payebU on April 1 to itotkholden of 
meord oa F*br«ary 20. 



RiDnmwtAi. B«Miu 4:«i< Rxr.ii 
embellii h a m ile (or thr in<>unl~l p 



dtgJ. 



n*'l '0*r»ri<»r >* n -• n if'f 



"'. ' ive Mvi) a good nuny 

■f Ibweiaoaeor other 

"<ired dilsre in the war. but 

"•doctten sad m Ute n- h yrl 

with e mtWs whioh is iwirig 



th<ui that which a Felzval may &iK>w. But always tta type 
of lens and the purpose for which it is required must be 
considered. Just as the size of tta ciixdes of full and semi- 
illumination im'rc«»<? as the stop is reduced, so also should 
the circle uf good definition, ii the lens is at all a reasonably 
good one. The most serviceable lens ia one ttat with a 
modeiBtoly small stop will oover tta plate with both eve^ 
illnmination and good definition, and one of tta moet import- 
ant differencea between good anastigmats and R.R.a is ttat 
tta fonowr will do this witii mtidi tta laiger stop, tta result 
being that as a rule they require only a half or one-third 
the capoanre. Tbis brings me to anottar of tta points re- 
ferred to by Mr. Nicol. He mentioned several oases in which 
RR.s would serve juat as well m ansstignata, and several 
waya in which phologra|4wra coold waate mctiey on 
enienaive Unam when cheap ones wonid tave done aU ttay 
required. Tta fact seeras to ta ttat many photo- 
graphcsa do not quite understand wtat is meant 
by a high dsgree of corieotion in a lens, and |>laoe 
a value on it ttat their requirements do not justify, ("irst 
of all, we must premise that no lens is perfectly corrected. If 
we Met two lenses, an RR. and an anaatigmat, at a certain 
moderately oblique angle, and use a critical test, we atall find 
astiyBati^i in tath of ttasfi. It may ta clearly obvious in 
the first lens and only just pwtoaptible in tta ottar, but it will 
exist. Clearly the anaatitBiat ia tta tatter corrected, tat still 
not theoretically perfect Next teet tath lenam by exposure 
on a tmt subject. The chaaem are that tta aberration is not 
viaiUa in either. The small defect that our microscopic test 
iwvealad is marked by tta inherent defects of the photographic 
procam. A miaute spreading of the light-effect, or lark of 
safflciiat lasnlriBg power in the plate, or pertaps lack of 
minute detail in the subject, baa rendered tta lens defects 
quite inviaihle, and, therabre, negligible. It is then evident 
ttat tta B.R. is doing tta work quite as well as the photo- 
grapher ca> desire, while tta anaatigmat is merely an instru- 
msBl of grmter |>r>V'>Mia than he needs. It bigger angles 
he will And maikad difference*, while always tta anaatigmat 
should ta tta quicker lens, but if he doea Bot use wide angles 
or start exposures he lan do without tta anaatigmat quite 
eaaily. 

Yet aaulber point i» that the special advantagm of tta anaa- 
tigmat sre r>ft*ti arrived at by various means of oampromi»es. 
A 1 ' 'ical definition pos- he centre of the 

fiel<l , r the sata ol gettiii.: iing more im(>or- 

taot. It has been said that for fine central definition no lenit 
yet made toinw up to tta Petxval Portrait, while it is cer- 
tainly a tact ttat some good RlL's will give central definition 
of a kind that should satiafy the most critical ptatographer. 
Somehow or another, when aa eatiemely fine focus is required, 
even though on only quite a small area in the centre of the 
field, tta tendency seems to ta to rush for an anaatigmat, 
when all tta time a mach cheaper leas would do the woric juA 
as well and very possibly even better. 

< '. WcLBensB Piruu 

iMur III)', 73, Cotton lonr, 

V — . ..V .i.... ...K^o-o uh vo^racter of theiw it thsl 

Ay in several ootours (reproducing with great 
i,.m " " original), bat also tta relief of tta originol 

- reprodoced, and gives to tta wtale badgp 
and distinction which is not secured by 
sny fgn* of r> n in tta flat. At present the only bsdf|i<- 

aodribboawbi " - thooeof the RoyU Flying Corpr. 

but tta Bedgr iDipany are in hopes of addinx 

ulher branches «i wk .^TMr,' i., Uirir list as rapidly as nuirt' 
taring facilities will pMmit. In the meuitime, it is cprtainly 
while for any nultrr »( |M>rtra>t« who drjuret to obtain a badge -wiikii 
will br a dixtmctioii u> » mounted print of hawfvw high a character, 
to apply to tta 4 ooipany (or particulars and price*. 



lata 

aa e|ijiivrsiH^ 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[February IS, 1918. 



SCIENTIFIC DESIGN IN OPTICAL PROJECTION. 



III. 

[A week or two ago we quoted from a paper before the New York Society of Illuminating Engineers on a system of regulating 
illumination upon the projection screen in accordance with the conditions which make for the optical comfort of an audience. A 
further paper before the same Society now deals with a subject which has a much more important bearing upon optical projection, 
inasmuch as it is an investigation, as regards effective illumination of the projection screen, of difTerent systems of illuminating 
the lantern slide or othet< transparency. The author, Mr. J. A. Orange, of the General Electric Company, is presumably in- 
terested in showing the superior results which can be secured by means of some metallic filameqt lamps used in accordance with 
an optical system which is quite different from that hitherto employed for other light-sources, such as gas mantles, Nernst and 
arc lamps. But as it appears that the use of a metalhc filament lamp for optical projection is being actively developed and 
promises to revolutionise the construction of optical lanterns, a study of the principles of projection as set forth by the author 
IS certainly to be recommended to those who, after the war, will be returning to the manufacture of th^se largely sold articles. 
The meta ho filament lamp has much to recommend it on the score of convenience and constancy in comparison with an arc. 
and If It turns out that its introduction for projection purposes is the occasion of displacing the familiar type of lantern con- 
denser from the vogue It has enjoyed for many years past, it is obviously necessary that constructors in this country should keep 
Delore them what progress is being made in this direction.— Eds. B.J.] 



1-16 
1-16 
1-16 
1-16 
1-16 



Atteb this preJiminary account of motion-picture projection, 
simplified by omission of aU reference to moving parts, one is 
in a better position to review the actual requirements. 

Standard practice involves the showing of sixteen pictures 
per second, each picture being held stationary in the proper 
position for about 5-6 of the working period of 1-16 second. 

It is necessary to interrupt the projection during the short 
intervals in which the film is moving, and further, since 
flicker is intolerable at 16 alternations per second, it is cus- 
tomary to interrupt the projection 32 or 48 times per second. 
(Thus for the latter case a cycle would be : 
1-16 X 1-16 sec, film moving, projection interrupted. 

1-16 sec., film stationary, projection proceeding. 
1-16 sec, film stationary, projection interrupted. 
1-16 sec, film stationary, projection proceeding. 
1-16 sec, film stationary, projection interrupted. 
1-16 sec, film stationary, projection proceeding.) 
The necessary interruptions are effected by the rotation of a 
shutter, a circular disc with sector openings, at a suitable posi- 
tion in the path of the light. A 2-wing shutter revolving 16 
times per second gives 32 interruptions, and a 3-wing 48. 

The only reason for using the 2-wing shutter is found where 
60-cyclo alternating current is used with an arc-source; were 
the 3-wing used, its frequency of 48 would give stroboscopic 
beating with the 60-cycle pulsations of the light-intensity. 
i<licker IS known to depend on intensity of iUumination (or 
more strictly on surface brightness) as well as frequency. Now 
while the intensity used is unlikely to produce appreciable 
flicker at a frequence of 48, it should be remembered that 
there is tho inherent 16 per second jumpiness of the picture 
details which are in motion. 

This is an argument for restricting the brightness of the 
projected picture; it would seem that eye-strain may occur 
with two very different outfits, the alternating-current arc 
giving relatively low illumination and a frequency of 32 and 
the very high power direct-current arc giving high illumination, 
an unobjectionable 48 frequency and a 16 per second jumpiness 
which is prominent by virtue of the degree of illumination. 

The best form of shutter device is a matter of considerable 
importance. The requirement is that the shutter be closed 
entirely throughout each interval of motion of the film and yet 
at the same time that the time-integral of the opening be 
as large as possible. It foUows geometrically that it is desir- 
able to have a shutter which is large compared with the section 
of the beair. m which it operates. A number of alternatives 
are available : 

1. The so-caUed inside shutter, operating near the film, 
bince this operates in a very constricted part of the beam it 
may be made small and yet reasonably efficient. Apart from 
the general inconvenience of the position, there is the slight 



disadvantage that the different parts of the picture are not 
quite synchronous as regards the pulses of iUumination. 

2. The standard shutter used with the system which employs 
a 4-in. condenser opening at long range from the film. This 
system is characterised by a small image of the condenser- 
opening a- short distance ahead of the objective. The shutter 
is placed in this image-position, and may then be made small. 
There is some slight advantage in the fact that the whole- 
picture waxes and wanes in brightness together with this 
method. The on© objection is the stopping (diaphragming) 
effect oi the condemser-image (so to speak;), that is, there is a 
restriction of illumination which is more serious than the 
gain in shutter design. 

3. The remaining case is that in whicJi large condenser-aper- 
ture is used and limiting iUumination attained. The inside 
shutter may be used if one cares to tolerate the inconvenience. 
AltemativeJy one would select as shutter position a plane 
immediately in front of the objective, such being tho smallest 
section of the emergent beam. 

The beam section is considerably larger than that utilised in 
the usual arrangement (2, above), and consequently the shutter 
should be scaled up in proportion, if efficiency is to bo main- 
tained. 

Some interesting variations are: — 

(a) A pair of shutters working in opposite directions through 
the beam ; these can be made smaUer than a single shutter 
for any given efficiency. 

(6) A small one-wing shutter working at treble normal speed. 

Finally, there is a question of choice of light-source for 
moving picture projection. Theatre work has depended almost 
entirely upon the carbon arc. It might, be thought that the 
superior brilliancy of the arc would constitute an invincible 
advantage, but when one examines the optical train used in 
this work it does seem that a source of lower brilliancy could 
be utilised, given appropriate arrangements. It is a fact that 
the majority of objectives in use have a much smaller aper- 
ture than might be provided, and moreover, the stop constituted 
by the condenser-image is a needless obstacle. Thus in any par- 
ticular case the illumination at a screen point, — Jc, may 

a;'-' 
be obtained just as readily by increasing A and decreasing B, 
that IS, by increasing the effective aperture of the objective 
and decreasing the source-brilliancy. 

(The contention that large aperture may be coupled with arc- 
brilliancy and thus still higher screen illumination obtained is of 
no consequence. The main interest centres in such intensities a» 
are giving commercial satisfaction to-day. The connection between 
intensity and flicker has ahn a bearing on this question.) 

The extent to which objectives may be improved as regard* 
aperture cannot well be discussed here. Suffice it to say that 



VoltfUiry 15. 19iaj 



THE BRITISH JOURNAL OF PHOTOOR.APHY. 



79 



s certain v«Jl known moving pictai« camera lens has 3-in. 
!? '^ - 1 focal ler.-' - ' '1.9 aperture, which gives scfne 
. of the J' 
li.e largest-aperture (iTvjection objectives in regulaf use are 
abuat f 2.2. Such an aperture wlien used in conjunction with 
a sj^-'inl tungsten lamp and rou.:)ily lintiting illumination 
coiuirit.ns viU give xreen intensities oi the order of those 





n(. 6.— Aapaet of BM(ie Uawni ohjwlix- from rcQir* ud ddc o( wnaa, thoif inc 
▼«ri«Uoo In ATUikbitf %;«ila(«. 

fonnd in present commercial practice. It shonld be pointed 

out t! '>bjective in mo*t ttbting iastallations 

i« ''' '-'it. An increased allowaaoe in this 

- vefj. dekU-ahle, in view dL th* importanoo of its 



APPEXDI.X— MAGIC LANTERN .^ND MOVING PICTURE 
CALCULATlOXa 
The limiting iUuminatioo at any icpiio point m 

a) 



i-5jUx» 



where B is the ^oaroe brilliancy, A is the apparent opening of 
the objective relative to the point in qnestion, > is tb* throw 
and k IS the coefficient of transmisaion of the aysten. The 

» apparent opening of the objective often varies in ma^tude 
tor diB«?rent screen point*, particularly in the case of the 
magic lantern. This is analogous to ill* variation obtained 
with a window in a thirl •■ -n i i i ^jng^ 4, <,oe travels past, 
and is known aa the vi i of dt« objective. (See 

Fig. 6.) In general, limiting i.iu ii not atUined, that 

is, the eflectrre apertare of the for any particular 

~ ■ ' : int (and in jfric(ius>, fm ai,^ oattptdral colour) is leas 
,1 ' whole apparent opening or gnaa apeotnre, and 

I s= — — j — X k, where a ia the ffMUwt objective apertare. 

From the further relation* : 



and 



/ - 



where f is the !ocal length of the objective. 
' . IS the linear nafnification, and 
n u the efiective namerical aperture* oi otijective we obtain : 



--'-.V- 



(2) 



Tkx OiRMJkw Vtifrtniininnr IvwriRT m 1917. — In the first two 
year* c,( thr -.rar tlir ' N.rldeatjehe .^Ugsmeina Zeituog " is in- 
f..r.. . I ''..in l>rr4jcii), it A|>p«ar«d ih ■■ ■S»- r-nnufacture of cameras, 
•-ganled more or Iss* m nilualrv, would have 

. . ..inca if the war lasted kmt; • mc ijmdtn firms, which set 
' >ne (or the inJoslry as a wh<il>-. wers asceedingly caations in 
■ • •' - • - • tj^, pr, . ■>-.- ,v«n expected to have 

B<it th« .\ _. of the cameia indus- 

onuiiioiu soon dijp< I i these anxieties; the army 
'ed pbotograpby more arid Mote, and made such de- 
ne lodostry that lbs Ut> !,le to cope 
For the pnrpeee of o .y delicate 
' cam* B s cu ssi r y , to graul Uavs from the 
workars. Outp ite requirements was, con- 
ie<l'i«ntiy, murs and more rsatricteJ, ...th th* result that' th*r* is a 



This implies that, other things being equal, magnification 
and effective numerical aperture* should keep step if constant 
illumination is requiresd. Hence the amateur's outfit giving a 
3 to 6 ft. (1-2 metip) picture is well enough served by an objesc- 
tive woricing at small aperture, while a theatre outfit giving a 
12 to 20 ft. picture calls for proportionately extreme numerical 
aperture*. This comparison is on a lba«8 of equal film size ; 
ii the amateur's outfit uses miniature film then the magnifica- 
tion is necessarily higher, and with it, the lens aperture 
requirement. 

With regard to the common inquiry a« to the projection of a 
fixed size of screen picture at a short throw and at a long, the 
answer is that different focal lengths of objective w'ill be re- 
quired, and ii these are of th« same numerical aperture* the 
illumination will be the same in the two cases. Since commer- 
cial objectives are of fixed diameter, in focal lengths, exceed- 
ing a certain moderate value, it will be seen that with rela- 
tively long throws the possible illumination at constant pic- 
ture size varie* inversely a* the square of the throw. 

A third relation which is of interest in testing projectors 
may be derived as follow* : — 



I-- 



,-.18 - 






•(3) 



where S i* the area of screen picture, and f is the area of film 
or slide But 1 x S is the namber of lumens in the projection 
beam 

Bfjc 
I* 



L — 



N.B. — In eqoation (1), I and x should involve the same unit 
of length — foot or metre, a* the case may be— and B and A 
should involve the same unit of area, square inch, square centi- 
metre, or square foot. In equation (2) if I is stated in foot- 
candles B should be stated in candles per square foot. In 
equation (3), B and i should involve the same unit of area. 

Rough values of the factors which together make up the 
constant k are a* follows : — 

Coefficient of transmission of objectives 0.65 

Coelfioient of transmission of two-lens condenser 0.7S 
Coefficient of trsnsmiasion of projector shutter 0.50 

ADDITIONAL REFERENCES. 
Bppetutei n (1), " Die Vergrd**emden Projektionssysten " 

(2), " Die Beleuchtungssysfeme," Hantlbueh der Phyiik, 

Winkebnann, 1906 ed., pp. 373-75. 
Kmss, H., " Uber die Konstruktion von Kondensoren fiir 

Vergrossemng* and Projektions Apparate," Eder'$ Jahr- 

bwA, 1809. 

J. A. Obanoi. 

k — — ^ — ^ 

*Tb« tam "aamarlnl •ptrtare" U mluppllad h««. Ik ii eat'omu-lly 
•RtltaS ID ilisu Miuin obl9Ctiin Mid Ukr* Into oooaidartUoD tba n frscliTc Iii4ax 
of lb* aa^to with •bleb Ibv flret luu surtMi* I* in oonUet— > (actor wbiob ia not 
o > m»ti u »a la ofSlokl projection oalaaJMIou. lu Brnwlni, u OMd by Mr. 
Otabca. istlafir-r Na."-i:i». 



jhgrteg^rf cameras on the market. Despite a coiuiderablc increase 
io price, the demand is keen, especially from tbo front. Altogether 
the industry may be lalisiied with the results of the year 1917. 
Despite unpreocdcntedly high wages and prices for raw materials, 
the two Dreeden camera works will be in a poaition to oiTcr their 
shareholders satisfactory returns. The photographic paper and plate 
factories will also do quite well, notwithstanding the fact that they 
hav* bad to contend with an even more serious shortage of materials 
than the camera (artories. Since the middle of 1917, it hns been 
possible to execute trade orders only slowly and in small qiiantitiei. 
Vet there is no marked scarcity of commodities on the market, as 
the dealers laid in abundant stocks in good time. The anxiety of 
professional photographers lest they should be adversely affected 
by amateurs proved groundless, and the proposal to restrict amateur 
photography found no favour. 



80 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



• [FeblTiary 15', 'felB. 



Jlnalecta* 



K-ctracts from our tceeUy and nio^lhly conUmporariet. 



That Stale Fixing Bath Odour. 

"The acid in the fixing bath (writes M. F. Long, in " Camera 
/Craft" (or .lanuary) fretiuently keeps the studio perfumed with a 
'dead odour of sourness. This doe.s not bother the pliotographer, 
but is always noticed by his customers, who are ignorant of the 
source and its significance. The addition of a few drops of what 
may be called a iieutraliser to each gallon of the fixing bath lias 
proved a great help in overcoming the trouble. This deodoriser 
is made by adding a little oil of cloves to some petrol, about ten 
drops of the oil to each ounce of petrol. This can be altered to suit 
"the taste by using oil of wintergreeu or oil of cinnamon, and also by 
varying the amouHt of oil used, but it will scent the prints if used 
-too strong. A few drops of the mixture are to be added to the fixing 
bath whenever the scent of acetic acid is noticed. It has no effect 
■on the working of the bath, but the atmosphere of the workroom 
and studio is changed and freshened wonderfully. 



DEATH OF LIEUT. E. J. CURTIS. 

We liave to rec«rd with mucli regret the deatji in action on January 
22 of a member of the publishing stiff of the "British Journal," 
who was known personally, if not by name, to many of those who 
haid business at these offices. Mr. E. J. Curtis entered the employ- 
ment of Messrs. Greenwood nineteen years ago. On joining the 
Army he was for a short time with the Royal Garrison .\rtillery, 
being subsequently transferred to the King's Own Rifles. WiUi 
t-his regiment in France he took part in heavy fighting in the Sonime 
offensive of la«t year, aod subsequently, on recommendation for a 
commission, -lyas gazetted second-lieutenant in the Royal West Keiits 
in September last. 



Ol Messra. Greenwood's stiiff, of six eligible lor military service,, 
it may be of intei'est to say that two — H. S. Mills and P. J. \ix — 
have been discharged after active service, the one with the loss of 
an arm, the other from wounds and gns poisoning. Two others — 
J. VV. Aplin and G. T. Pike — are still engaged in the R.N.A.S. and 
Jtoyal Field Artillery respectively. 



FORTHCOMING EXHIBITIONS. 

February 9 to 16. — Glasgow and West of Scotland Amateur Photo- 
graphic Association. Secretary, G. S. JlcVean, 125, West 
Regent Street, Glasgow. 

'Februaj-y 16 to March 2. — Edinburgh Photographic Society. Sec., 
P. T. Mackintosh, 38, Castle Street, Edinburgh. 

February 21 to 23. — Leicester and Leicestershire Photographic 
Society. Sec., H. C. Cross, 80, Harrow Road, Leicester. 

March 12 to 15.— Hackney Photographic Society. Sec., Walter 
Selfe, 24, Pembury Road, Clapton, E.5. 

Ai)ril 18 to May.— Hampshire House, Hammersmith, Photograpliio 
Society. Entries close March 19. Sees., H. T. Callendar, 10, 
Aore Lane, Brixton, S.W.2; or W. T. W. Shiers, 201, Goldhawk 
Road, London, W.12. 



R.P.S. FoSTHCOMiNu Lectures.— The lecture, " A Few Words on 
"Bromoil," by Dr. C. Atkin Swan, announced for Tuesday, February 
19, and the two lectures, "Round About Grassmeie," by F. Hum- 
pherson, and " Nioholaa and Najwleon," by Bertram C. Wicki.son, 
announced for February 26, will not be held on the.se dates. Dr. 
Swan's lecture will be abandoned, and the other two lectures will 
ie transferred to April 9. 



meetlnss oT Societies* 



MEETINGS OF SOCIETIES FOR NEXT WEEK. 

MntlDAV, FebHUAKY 18. 

South London Pbotograpbic Society. Portlolio Exhibition. 

Dewsbory Photographic Society. •' ( andlelight Effects." H. A. P«rkin»on. 

City «f London and Cripplegate Pbotograpbic Society. *' Bromoil." 6. B. 

Clifton. 
Bradford Photograpliic Society. "Rambles with a Gamekeeper." W. J. 

Forrest. 

Tuesday, FSBRtTAKY 19. 

birmingham Photographic Society. "Pompeii." Arthur Clendon.M. A. 
Hanley Photographic Society, Y.M.C.A. Midland Pnotograpbio Federation 

Slides. 
Hull Photographic Society. " Beverley Minster." F. Webster. 
Sheffield Photographic Society. " Venice." H. Merrill. 
Keighley and Diitrict Pbotographic Association. Yorkshire Union Exhibition o' 

Selected Prints. 
Stalybridge Photographic and SoientiHo Society. R.P.S. Colour Slides from 

the Competitions. 
Monklands Photographic Society, " Aberdeen City— Ancient and Modern." 

A. Hay. 
Hackney Photographic Society. Onthelbamee. 
.Vlancbester Amateur Photographic Society. Kihibition of the Second Part 

of Mr. Wormleighton's Slides. 

Wkdnesday, February 20. 

Croydon Camera Club. " Floral and Faunal Remains Found in the Coal Measures." 

Dr. G. H. Rodman. 
Hull Photographic Society. "Further Roamings in Europe with a Camera." 

C. Oxtoby. 
Leith Amateur Photographic AssociAlion. Exhibition of Members' Work. 

TuCRSDAV, February 21. 

Liverpool Amateur Photographic Association. "Three Cities of Andalusia " 

Rev. T. J. Walsbe. 
Hull Photographic Society. Members' Slides. 
Huddersfleld Naturalist and Photograf^ic Society. 

up the Hebden Valley." s. (ire«nwood. 
Sunderland Photographic Association. Lectuorettes, 

Cross. 
Hammersmith (Hampshire House) Photographic Society. 

Pitfalls and How to Avoid Them." O. Uloch, F.I.C. 
Rodley and D. strict Photographic Society. Still Life Competition 



'* By Wood and Moorland 
J, W. Addison and A. K* 
Some Common Plate 



ROYAL PHOTOGRAPHIC SOCIETY. 

■The annual general meeting was held on Tuesday evening last, the 
President, Mr. John H. Gear, in the chair. 

In reading the annual report, the only item arousing comment was 
that of the exhibition. The President set forth the reasons which 
induced the Council to hold it in the Society's House ; notably that 
early in 1917 there was a strong probability of the manhood service 
.scheme being put into force, in which case it would have been im- 
possible to have carried out the arrangements at the Suffolk Street 
Gallery ; secondly, the entertainment ta.x would have had to b« 
paid for all members of the society whether they attended the exhi- 
tion or not; and thirdly, the deplorable state of the gallery, which 
admitted rain through the skylights. Even the papering of the 
walls would have cost the society at least £60. He paid a tribute 
to Messrs. Clifton, Portway, and Vivian Benjamin, who assisted 
the committee in its work. 

Mr. C. Smith said the only fault he had to find with the Presi- 
dent's speech tvas that it was too apologetic. The Council had done 
the right tiling in the right way, luid they all appreciated the self- 
sacrificing labours thfe President had expended. Mr. Hawkings asked 
if the society held the gallery on a repairing lease. Mr. Ferguson, 
K.C., said he was of the opinion that the ' proprietors of the gallery 
must either put the place in tenajitable repair or terminate the 
contract. Mr. Warburg, as one who objected to the exhibition 
being held at the house, asked what the loss would have been at the 
gallery. The Treasurer said it was impossible to say with certainty, 
but he estimated the loss at £160. He was thankful that the ex- 
periment had 'not Wen tried. The Trea/surer then dealt with tlie 
accounts, which, witli the report, were unanimously adopted. 

Mr. Lutnb moved a vote of tlianks to the President, who had been, 
he said, not a merely ornamental figure-head, although even in tha't 
respect he had claims ujxin the/sotiety. He had not only done his 



Febnunr 15, 1918. j 



THE BRITISH JODRX.VL OF PHOTOGRAPHY. 



81 



• luty but mora than hit datj. Mr. Fetgoaon leconded the vote, 
whioh waj carried uiiaiiinioualy, and Mr. Gear responded. , 

The report of the siruiiiK'eri oi the ballot was read,ahowing that 
Toting paper* to the number o( 131 were aent in, and the following 
ware the officers elected for the })rrsent year : — 

Pres..J..::t. Dr. C. Atkin Svan, MB., etc; Vice-Pre«ident», F. F. 
Renwu'k, Dr. G. H. Rodman; Honurary Treaaurer, A. H. Liaett; 
Ordinary member* of tlie Council. F. C. Boyes, A. J. Bull, Lieut. D. 
Cameron-Swan, G. B. Clifton, A. L. Cobum, H. Easeuhigh Corke, 
6 L. Coulthurst, W. B. Fargoson, K.C., T. E. Freahwater, J. D. 
Johnston, F. Marriage, F. Martin Dancao, C. H. Oakden, F. Sanger 
Shepherd. W. L. F. WasteU, J. C. Warfnirg. Ofi. Owen Wheeler, 
8. H. WratUn. 

Mr. Gear wekxnned to the chair Dr. C. Atkin Swan, who expreaaed 
hia diffidence in accepting the preaidency, and aaid he oonld only hope 
to carry oat the duties if be were accorded the whole-hearted sop- 
port of the Coancil and members. 

The qneetion of holding lectorea darinf air raids waa diacuased, 
and it waa agreed to abandon thoae ■ninnfTT^f' for February 19, 
February 26, March 26, and April 23. 

The raiftaining bnainaaa was of a {mrtly fonnal nature, and the 
meeting terminated at an early hour. 



CBOTDON CAMERA CLUB. 

Tbe annnal meeting fixtd for the 30lh nil. kmti the attcndanoa 
poor, poaaibly partly do* to the bombastic night air on the two 
praviooa days; the treasnrtr waa also laid up with a cold, so the 
proceedings were compolsorily held over. The fumtion last week 
■narked the ck>ee of a series of weekly lectorea and demonatrstions, 
which, for tbe third year in anccesaion, have bean carried through, 
winter and summer, afaaoat without a bnak, and faithfully die- 
stmolated in thee* coiamns. 

Rare indeed is it for a society to posasM saeb as aasrgstie sserslary 

as Mr. J. M. SeUors, a perfect marvel in nnaarthinf talent and sscnr- 

ing it for ths syllaboa. To bim most of ^he success of tbe psst year 

haa been due. Kindly members of other aodetias have also materially 

forgetting the newer membats of the dob, who have bkia- 

I a wonderfnl way, the infonaal sissinn bsiag of tsstit- 

■ trial trips. It is hopsd tkis fsaturs will be oao> 

t of tbe merry-making reesntly iadnlgsd ia at its 

cxpe:.j7 I .. .1 '.v\ :;ilcling twinUar reqraa^bU for a rsgnlar eoatribntioa 

in a conl«mi>tjrary. 

Under a rule limiting prceidantial rank ia any ooa owmbsr to two 
conaecnlive yeart, Mr. J. Keane autnmstifally sseoiss the mneh- 
coTcted order of the boot. In the opiaiOB e( all ha has partially liUsd 
the capadooa chair with suoosas and dMaelioii, and tactfully kept 
ius cfaargss in sen* sawMancs of order wHkoot a loach of the fatal 
" aehooimaatar " in oAca. Not that a sr^nlmMlsr eaaoot be an 
imapoasibla boy oat of sdiool, as on* popolar mswibor amply de- 
moottntsa. HaTJag regard to Mr. Keaaa'a gsnaral virtnca (cs o|lct^ 
a dittiact leadeocy to moraliss and iatrodnee clasaical tags can be 
forgiTtn. Mr. A. F. Catharias su cc ee ds him, and ia as diflsreat from 
his pradaOMMT ia atyW m chalk used to he from ehasss in tests. 
The lattar msw h a r , whca on the stump, seeks inspiratioa from all 
■orroaadiag space, and it nercr fails to sapply Tarisd atoiospberic 
i deas, and an elegant pbrasfology. oonchad in tbe aame dnlcet vein 
whatever the subject, be it BAmoil, or tk» tAcaey of rat poison for 
iU drridm The president-elect when fnutiMl Into Mi vocal effort, 
0|'' 'cntrates more on one spo' ir, or on the table-' 

tiui doea imt afford the same \^.^.j, »jl tends to Irrevity 

and ofascrvationa atrictly to the point. 

Mr. U. T. Dodsworth, who hn* pot In • lot of hard work as 
tt saai ir er. was succeeded by .Mr. t ('. Reynolds in November last. 



chronicled may the spirit behind the Statue of Liberty make itself 
decisively felt in the great cause it symbolises ! 



The accounts show £127 cxcew 
this year haa to be written off l 
tioos by tbe secretary on repaini 
for the year abo show* a profit. 
deesDcy to mign; the Ubrariar 
boy " bangs on to dust-up his fr 
^ '- t \ regrettable resignation 
lily jaauned (or the time 
ui* berring-pood — "Orcetings." 



'Htiea, though mora 
< ing to deoKxiatra- 
'ure. The trading 
ooncil has had tbe 
ii'i'iid, and the "office 
it hope of thanka or re- 
it ol Mr. F. J. Terry— photo- 
'^g. To abaent membera across 
I Mors another annual meeting is 



ROXTGEX SOCIETY. 
.\T tiie meeting held on February 5, Dr. Batten read a paper on a 
simple means of obUining "SUlic Current*", from an induction 
c«il. The method oonsiste in connecting one secondary pole of the 
coil to earth, whilst the other is connected through a series spark 
gap, osciUoaoope Uibo and a aeries condenser to tlie patient, who 
ia placed on an insulated stand. The function of the condenser 
would appear to be that of a high resistance. Tho advantages of 
the apparatus are tvro-fold. In the first place, it overcomes the 
troublea due to a wet climate, from which the static machine always 
anffers; and, secondly, it affords an inexpensive means, to thoee 
•''••dy possessing an induction coil, of obtaining currents similar 
to those produced by static machines. 

Mr. E. E. Bumside read a paper describing a now mobile snook 
apparatus. This is constructed on the same principle as the larger 
pattern hitherto in use, but is made in a more compact form by 
reducing the maximom spark gap to seven inches. 

Mr. Bumside also abowed a amall transformer constructed for 
empfeying the continuous-current main aupply to heat the spiral of 
the Coolidge tube. A small rotary converter changes the direct 
current into altemoting currant, which is stepped down to 12 volts 
by the static tranaformer. The aecondary is well insulated from the 
rest of the apparatus, and regnlation of the filament current is 
«*>tained hy a variable cboke-ooil in the primary circuit of the 
ttansfomter. 

news and notes* 

Th« PaoTOORArHic CoNTumoN.— At a council meeting of the 
Photographic Convention of the United Kingdom held at Anderton's 
HoUl. FIsH Street, EC, on the 7th inst., Mr. Walter Potter and 
Mr. F. J. Mortimer were elected joint honorary secretaries and 
t r ss sn rsrs in place of the late Mr. F. A. Bridge, and Sir Cecil Herts- 
let — who was present at the meeting— as co-trustee with Mr. G. W. 
Atkins. It was decided to hold a one-day meeting in London, in 
order to transact the statutory business, in July next. The ren- 
decvoos will probably be at the Zoo, becauai of camera restrictions 
elsewhere, with an evening social meeting in the city, should time, 
cire nw s t a nce s, and the Food Controller permit. 

A FuaTHia Rise im Platb Pricss.— It is announced that from 
February 5 last a further incrsase on the list prices of dry-platee 
pravionsiy prevailing is being made by the manufacturers. These 
latest pricss are;— Quaiter-platee, 2s. 9d. ; postcard, Ss. ; half-plates, 
6*. ; wbol»^late, lis. 6d. ; 10 by 8, igs. ; 12 by 10, 28s. We under- 
stand that they aj^ly to the manufactures of all the firms in the 
trade oae of whom, in notifying ourselves, states as the cause of tlie 
further inc r ease the continued . rise in tbe ooste of raw material, 
labour, and general manufaoturing expense*. This latest rise 
averages to about 20 per cent, increase on the prices whioh have 
been prevailing siooa Ma*|^h 1, 1917, when prices underwent tho 
fifth of a aariss of advaocea, the first of which was on June 16, 1913. 
We may hare reatat* ia ita complete form the diary of plate-price 
rises whioh we-publisbed a year ago : — 

s. d. 

Before June 16, 1913 1 

_«.^Jnne 16. 1913 1 3 

March 13, 1915 „..„ 1 6 

February 29. 1916 ._ 1 10 

March I, 1917 2 3 

FM>mary 5, 1918 2 9 

It will be uodemtood thai theee are the retail list prices for one 
doaen |-plates, and the series otarka the succensive increases (onu 
of them before ths outbreak of war) which have been made within 
the (KMt four years. 

loDtx* RKDt7ans.^Aa abstract in the Journal of the SociHy of 
Chtmieal Imlu •' .■ ' " i-ulars of a paper con- 

tributed by t • lii-oher and M. Winter- 

stein— to the Zi :' 'I r.ft tnr 11 xfcn'.hnflhchf. Photographir, 1917, 
pp. 1-16 : — " Iodine can be used as a plioU>Kr.%phic reducer in solu- 
tioD in potassium cyanide, in potassium iodide, or in aloohol, and 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[February 15, 1918. 



«l»o ia 4X)mbmatiun with thiourea. Tlic solution in cyanide is not 
itatisfactory in use because of the continued action after removal of 
th« image from the reducing bath: treatment with hypo stops the 
1 '1..I1 of tlie iodine but not that of the cyanide, which is still con- 
- il.rable, aa cyanide itself has a definite reducing action. The other 
N •'hods of using iodine are free from this defect, hyix) having an 
M luodiate arresting effect on their action; on tiiis account very 
thorough washing is necessary before treatment with an iodine 
reducer. Very dilute solutions are recommended :— For plates (a) 
1 to 4 CCS. of iodine-potassium iodide solution (1:2: 200) in 100 
CCS. of water; (b) 2-8 c.c.s. of the iodine-potassium iodide to 100 
CCS of ^ per cent, thiourea solution ; for paipers, solutions about 
half iho strength of those for plates, or a solution of from 4 to 16 
c.c.s. of iodine tincture (1 : 100 c.c.s. of 95 per teat, alcohol) to 100 
C.C8. of SO per cent, alcohol. Tlie time necessary for reduction 
varies from 1 minute to about 6 minutes with the first two baths 
and up to as long as 10 minutes with the alcohol solution. The 
ix>tassium iodide and alcohol solutions give a yellowing of the image 
by the formation of silver iodide, but it is quite easy to judge the 
amount of reduction. A final bath of hypo is necessary to dissolve 
the iodide and to arrest the action of the reducer, for .the latter 
reason also after the thiourea bath. The strength of the thiourea 
solution must not be appreciably higher than 4 per cent., as, although 
the authors were unable to confirm pj'evious statements that thiourea 
itself has a reducing action, in stronger solution its destructive 
action on the gelatine film is quite marked. The reducing action of 
iodine was compared with that of other reducers; it resembles 
cyanide and Farmer's ferricyanide-hypo reducer in acting evenly 
over tlie whole image, in contract with permanganate, which acts 
]>roportioiially to the depth of Uie image, and copper oliloride and 
ammonium persulphate, which adt more strongly on the shadows. 
The solution in potassium iodidej l>ut not the alcohol or thiourea 
solution, gives the usual hlue colour with papers containing starch ; 
it di.sappears, however, immediately in the subsequent hypo bath. 



Corresponaence* 

— # — 

".• Correspotuients slumld never write on hoth sides of the paper. Jtio 
notice is taken of communications uiiless tlie names aiid addresses 
ef tlie writers are given. 
*.* We do not mulcrtake responsibility for the opinions expressed bift 
our correspondents. 

PASTEL COLOURING. 
To the Editors. 
Gentlemen, — Even at the risk of being referred to your Advertis- 
ing Department, we would like to tell your correspondent, " T. A.," 
that our " Bertha Retouching Powder " was introduced more than 
ten years ago for the express purpose of meeting a well-known want, 
i.e., a means of giving to bromide prints a " tooth " that will hold 
powdered chalk and the like. It can be used on all kinds of gelatine- 
surfaced papers, and needs no skill in application. — Yours very faith- 
fully, 

The V.wguard MANUFACTuniNO Co., 

\V. Ethelhert Henry. 
Maidenhead. 



THE SENSITOAfETRY OF PHOTOGRAPHIC PAPERS. 
To the Editors. 

Gentlemen,- -Those readers of the "B.J." who have been inter- 
ested in the discussion of the albove entitled paper must have already 
reviewed it in the January, 1915, issues of this magazine, and thus 
formed their own opinion of its merits. Mr. Storr's letter of January 
4 last clears up any misunderstanding of his attitude toward the 
experimental methods and results of Mees, Nutting, and Jones, and 
indicates that on this important point our views were not divergent. 
Further discussion is, therefore, unnecessary. 

It will be understood, of course, that any seeming asperity in my 
letter of December 14 was meant only in the Pickwickian sense. (I 
was going to say Croydonian sense, but that would have precipitated 
another and more serious controversy.) — Yours truly, 

R. L. Stinchfield. 

736, Hotel Richford, Rochester, N.Y. 



ANASTIGMAT v. RECTILINEAR LENSES. 
To the Editors. 

Gentlemen, — Mr. Nicol's recent article on rectilinear lenses and Mr. 
Watson's letter on the same subject were very interesting. For plates 
up to half-plate size, however, an anastigmat seems to me to be 
the best for all-round Work, and will equal the rectilinear in bril- 
liancy if a type with four glass-to-air surfaces is chosen and the 
front lens is shielded when the wide angle is not required. A 
rectilinear limits the use of the rising front and enlarging lantern. 
As regards price, a good rectilinear must cost about the same to 
manufacture as, say, the Aldis anastigmat. 

It is curious that cameras specially built to give a very great rise 
and long hellows extension should be hsted with ^/4.5 lenses of 
narrow angle and single focus, some vest-pocket cameras, on the 
other hand, being fitted with expensive convertiWes. — Yours faith-' 
fully, 

rx)uis Nell. 

February 6, 1918. 



FIXING POWERS OF HYPO. 
To the Editors. 

Gentlemen, — In your article aibout hypo scarcity, of February 8,, 
you mention a maker's recommendations to use 1 lb. of hypo to 150 
(one hundred and fifty) p.c.'s. Considering the great scarcity, might 
this he a misprint, or does it go to prove what many photographei-s 
believe — i.e., that makers' instructions are valueless, for it is cer-' 
tainly very exti-avagant '' 

Having oome into contact with some millions of ibromide prints- 
dui-ing the last decade, my experience has been tliat a pound of good 
hypo will fix close on 600 (prints — ^-plates and p.c.'s — with care, and 
in any case should do 400. I have prints hy me that have stood 
the test of time after fixing on this scale, and I have seen thousands 
toned without any trouble. 

It is, of course, necessary to use the hypo reasonably to ensure this 
economy ; one would be lucky to get a hundred peiinanent prints 
from a pound if the latter were mixed to jxiste with alum to make 
a "fixing" bath, and yet similar things can be seen. 

Appreciating the great value of your infonnation with regard to 
the present hypo shortage. -I am, yours sincerely. 

Thermit. 

[We quoted correctly from a maker's circular. Certainly, we 
think the number small, but our view, as stated in the article, is 
that any rule for the use of so niuch hypo per so many prints is 
very liable to be abused. — Eds. "B.J."] 



DEVELOPER POISONING. 

To the Editors, 
Gentlemen, — Last week you published a letter from Mr. C. M. 
Foster in which he gives a recipe for developer jx>isoning (metol, 
I presume). He stiutes the same to be Ung. Methyl Salicy Co. P.B.C. 
(British Pharmaceutical Codex). May I respectfully point out he 
is quite in eri-or, both regarding the ingredieute and the quantities 
in the fonnula 't I have never seen a recipe or prescription being 
composed of hydrous and anhydrous lanolin (Lanolin Hyd. and 
— nhyd. 35), there being no use for such in phannacy. It may be 
one or the other, but the hydrous is mostly used, being softer to 
work up in ointments and, I believe, more readily absorbed by the 
skin. 

Fui-tlier, 35 ? Does he mean 36 pairte of a mixture of the two fats, 
or 35 (Mirts of each? As written, I sliould tiike it to mean the former. 
Assuming this to be so, the menthol works out at 26^ per cent., 
against 2^ per cent, in tlie official fonnula ; but the methyl salicy- 
late quoted is correct. 
The formula for B.P.C., Ung. Methyl Salicyl Co. is :— 

Methyl Salicyl 125 

Menthol 25 

Oil Eucalyptus 25 

Essential Oil of Camphor 25 

Hydrous Wool Fat 25 

Paraffin Ointment to produce 100 

To have an ointment containing 26 per ceut. menthol a{>plied 



February 15, 19ia] 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



83 



to a teinder surface, such aa that prodaced by meiol ia enough to 
•rnd one a»zy for the time being ; I ahoi^d think the pain almost 
unbearable. 

The came remarka apply to the application of citric acid ahoold 
there be any open places. 

Penona'.ly, I have never had an attack Irom the use of metol 
or theee am:d<4>hn)ol developen, but I think, from what I have Men 
frum clicntii at different times, that the trouble can eaaily b« pre- 
vented if precaution is only taken. To w^ until the trouble baa 
been caoaed and then expect an ointment or other remedy to core in 
one or two applioationa ia beyond reaaon. Metol being a phenol 
or oreayl hard compoand, ii naturally attack* the ikin in a oanatvc 
or eatin,; actkm upon the aorface. 

To all naera of theae developer* I would anggeak, first of all — 
cleanlineas— that ia, aa loon aa developing ia finiahed, to waah the 
banda well with hot water and aoft aog^t (gettii^ rid of the caustic 
dieoical left on the akin). 

Dry well, and then apply a Uttle fatty oil, such a* almond or 
oHvt>. nibbing well into the hand and ao keep tiie lorface soft and 
y I tt ." to prevent crackii^. At bedtime rob this ointment well upon 
the afiected parts : — 

Zinc oxide „m*»-— •••. 1 Dram 

Camphor »»»,. i Dram 

L«aolin>.- ,. i^, S Dnana 

Oil Almood 3 Dram 

(Tlie ainc is cooling, the oaunphor for irritaUoo, and tba lanolin* 
and oil for aoftening.) 

In conclnaioo, I would like to warn imdtn afainal radpca and 
supposed prescTipbona whiob are so olUa pobkahsd in ioqniry 
columns, eapecially thoaa in ladies' jourwila, w^era advioa is ao often 
asked upon complaxioo and skin mattara. The recipa pobUabed 
laat week baa evidcotly (in my opinion) bean obtained by aoch 
eoime in the tint place, and abow* plainly that thoa* wfao tandar 
such formula, neither nnderaUnd the cooplaini tbay treat, oor tbe 
oomfMsitioa nor use o( the dmga they iwoauBsod. 

Jamm Dtmimio 
(Maoibar PfaannaMiitical Sooiaty of Oraat Britain). 



I 



PLATF. SIZKS. 
To the Eailora. 

Oanllsmcn, — Yon ara right in yorfr iiaiti about tha popular 
aisaa of plates being too aqoars in sha^ bat orliKidoz aixaa are, 
I fear, too ftrmly aatnUialiad to be oualad iron Iha markst. The 
new Kodak 11 x 7 ail* Bay ba taken i^ by anyoo* nqoiring a new 
oameta or, of cour**, ooa say oae it in a 12 k 10 camera by mean* 
of a carrier. It is a great pity lit* 7( « 5 •:«-— .\roencan, too, I 
believe — went out of fashion. It pmtn >*f« in England, 

J.,it wu »v«ntiniu- knocked out by the 1—.^ ^.-.-. 

\ :i Franca ia the 13 x 18 em. (rooghly, 7 x 6), 

I..,..-, in France I slwagm »sd it, aapoaing some 
■It axe. Thf dimanaifins are good, bat the 
«x;.is ka.f ^..lii ..4. .i. my opinion, an imffottaktv/i. 

I wonder wbo it was that act the faaUlB «l oor ataodard aizea. 
C —.. K^ rht'a catalogua ot Daguerraatjp* OMBaraa, ilated 1846. 
■lea and balvaa aa they ■• te-da y 8t x 6^ and 
oj X 4] Dut the quarter -ftlatr ' ~ u 4| x 3^. Roaa't camera 

kst, pobliahed at tb* end of "Photographic Preniiar." 

dated 1854, givaa tb* aixea ior ^: ' (lor wet plate wo.-k) 

•aaetly as they an lo-day. The • pobliahed by Newton 

o( Fleet S tw a t givaa oaaMras (or Ia^ ng piatea 9x7 and 6 x 6^, 
Ih* size* oaad to^y not faaing li«ted. Tba list cootains dstajJb of 
the UagnMTaotype p wit aaa and no others, and in a " Photogenic " 
list, also nndatad, I find 9^ x 6^ *i> i 11^ x 9^ reaanm*ndad. I 
bav* no deaire to erect a monument to tb* woirkar who ■lalilialml 
the firsssat-day whole, half, and quart** plat* aiaea, but aa yon 
have aHrsy* paid particular atten> 'oj^raphic history, you 

or your readers may b* able to tr.. -gin. I have moat of 

the handbooka and liata iaaued dur.' ,; -Jie ^nl thirty yeara of photo- 
irrapbT. hot the aore I itndy t)i>.< qnaation of aixoi, the mor* 
.• .11 ! I g.t. 

\:.- .' iv, the day ol smatlar sixoii i* ooming, «r baa com*, and 
what we want to-day la a really ..-"od carrier, not only -for dark 



shdes, but for sheaths for use in a hand camera. Comparatively 
little at^ntion has been paid to carriers, as in<iuiries at*dealers and 
searches in the files at the Patent Office testify. We have carriers 
which in many caees serve their purpoee, but we could do with 
something better. — Yours faithfully, 

L. Tennant Woods. 

To the Editors. 

Gentlemen,— I am glad to see that yon have a good word for 
plates in which the length ia greater in proportion to the breadt.h 
than in the rather squat proportions of the half and whole plate 
12 X 10, etc. 

Very early in my i^oto^raphic experience — sooie 42 years ago — 
I changed from half plate to 7^ x 5 for my chief use, and have 
never regretted it. It is about the smallest aize for iraming, and 
the largest (in weight of apparatus) that an average man caree to 
take about on foot. 1 have never had any difficulty about getting 
platea. — Yours truly, 

AvrzMD Watkws. 
Hereford, February 11. 



ilnsioers ro Correspondents* 

SPBCIAL NOTlCa. 
U mn m fmt of feneral rtduud lupfliu of paptr, a$ Us r«sa<l 

of froMhilioH of the imporUHion of stacA tpood pulp and fratt, 

9 tmalUr ipact wM t« avaiUMt mmtU furtAer noHot for ropliu 

ta SSI rai yii a rf aal*. 
y*ra»»«ir. <a* latfl awstesr 6y y>«« if Mawtpid m»d addrtutd en**- 

toy* it omelott d for rapfy/ S-c»tU InUmationtU 0oupon, from 

rta d tri abroad. 

»** fnU fmiatitmt and gnawer* will U prinltd onlf in the too* of 

iafwris * of fnoral imlmtt. 
QuorJM to ho antwtrtd in lAs Fridof't " Journal " mutt reath m» 
Mt lator tkan Tuudof {poUod M ondaf), and ikould ho 
a dd rnot d to lAa Mditero. 

ArtD SnraiTX. — The acid sulphite solution consist* of water 8 ozi., 
anlphuric acid ^ oz., and a quarter-puund of sodium sulphite cry- 
atals added. The bottle ia shaken until they are diasolved. 

Clkaxiko BnoMlDXS. — How can I beet clean up bromide prints, in 
th* absence of methylated spirits? — N. B. 

We have found petrol or benzols to answer very well, but if you 
cannot obtain these, you can nse a weak ferricyanide reducer on 
the wet prints, rubbing gently with cotton wool. 

Book StuOic— You must place the sitter where yon find the best 
light. We (hould prefer to hay* the background for full length* 
in front oi tba fireplace and towards the window. You should 
block up the window* abont 4 feet from the floor. For heads we 
dxiald rooanmnuJ a small backgr^MniH mi !,;-i, wlil.li you can 
place near the window. 

AypMn— ~T o« Paper.— The only procons wtntn i.i mmmerdally 
avauable in this country for the reproduction of Autochronies is 
tba naual process of half-tooe Uiree-ookmr reproduction. For 
math work you should apply to a good photo-engraving firm. 
Tnar* are no paper* or aecasMriea on sale here for tlie reproduc- 
tioit <A aotoohrome* tM paper priota. 

Flash Bao.— We do not know of any maker of flash-bags in this 
country. A method published recently is that of using an 
umbrella frame as a support, with the bag hanging down about a 
yard, and then gathered round the stick, which must be length- 
ened. For big jobs like yours you would have to do ss the 
Amerioaiu, who use a number ot bags at once and ftre the flashes 
simultaneously by electricity. You can fireproof calico by soaking 
it in a *trong solution of tungstate of soda, or, failing that, a 
atrong solution of common alum. 



84 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[February 15, 1918. 



i^mno Root Cfbtabjs. — Will you kindly advise me as to whether 
the encloapd material will be the best obtainable for studio roof 
curtouns (I am having white ones also)' If not, what shade of 
caeement cloth do you consider will be better? The portrait 
studio has a large amount of roof light facing east.—E. C. S. 

The colour of your sample is all right, but the material seems 
rather too thin, especially for sunlight. Try and get a thicker 
qtiaUty, or try Bolton sheeting. This in dark blue and black 
stops all light, and is used for "Zeppelin" curtains in many 
studios when working by electric light at night. 

Emulsion k)r Dry-Plates. — 1. Four hundred grains of silver 
nitrate will be equivalejit to 280 grains of potassium bromide, but 
an excess of the latter is l^equired to produce complete precipita- 
tion of the silver. The same amount of silver will be equivalent 
•to 390 grains potassium iodide, but only a very little of the iodide 
is wajited in an emulsion. You might try 10 grains. 2. There 
is no modern work on emulsion making. You can get general 
ideas from Abney's " Instruction in Photograjphy," and a very 
good article by A. Cobenzl on emulsions for photographic papers 
appeared in the "B.J." for September 12, 1913. This number 
is still obtainaible from our publishers, price 4jd., post free. 

E. H. — Commercial trade printers invarijibly "size up" a nega- 
tive for exposure, or make a, teat on a square of paper, say, Ij x 
li inches. Also a very common practice is to have fixed up in 
the exposure room a frame of negatives illuminated by diffused 
light, with the exposure required for each negative under given 
conditions marked on it. There is a blank space for the negative 
to be compared with these, and usually the arrangement allows 
of the negatives being shifted to and fro, so that the newcomer 
can be fitted in for the better comparison with the standards. 
A density meter such as those you name is certainly of some use. 
There is little to choose between the two. We should prefer the 
latter. 

Lenses. — 1. Wide angle and R.R. lenses being designed for different 
purposes can hardly be compared in the way you suggest. Tested 
under equivalent conditions on a small field, we should not expect 
to find much difference. 2. The wide angle should have the 
greater covering power— that is, it should cover the bigger circle, 
but it might require stopping down below f/16. 3. No, because 
the distance from lens to negative is greater in the enlarger than 
it is in the camera. 4. If reproducing the 12 by 10 negative full 
.«ize the 64 in. lens must be 13 in. from the plate, so tliat the angle 
covered is not so very great. It is, however, great enough to 
.suggest that the lens is a pretty good one. If reproducing on a 
smaller scale, there is nothing exceptional in the performance of 
the lens. 5. Without trial we cannot say, but we should not 
e.xpect to find much difference. Possibly the single lens might score 
as regafds definition, but it would be very slow at that aperture. 

.Airn Fixing Bath. — 1. Is the enclosed fixing bath quite safe for prints? 

2. Are the fumes from acetic acid harmful, as I was mixing 6 ozs. 
acetic acid in a stock acid bath with sulphite and alum and I 
felt rather queer for some time? I had window open at the time. 

3. Is it safe to add alum to a hypo bath containing pot.-meta- 
bisulphite. — ^Kaix)K. 

1. Yes, provided the powdered alum is quite pure. This variety 
(if alum frequently contains iron, whioli reduces the prints and 
leads to toning troubles. If not sure of your alum, and if \xm 
cannot use the special solution, we. would recommend the 
chrome alum formula given in the Almanac. 2. No acid fumes 
are exactly healthy, and acetic fumes, though less harmful than 
othei-s, may very likely upset some people, especially in a close 
(lark room. If this is the case with you, it would be wisest to 
use another formula. It was most probably the sulphurous acid 
fumes that affected you rather than the acetic, and you would be 
likely to get far more of these when making up the solutions. The 
iiiixed fixing bath anay hardly give any. 3. Yes. 

Sh.\rp Line Scb.iect3.— I am staff photographer to a firm doing 
experimental work, and liave to take critically sharp photo- 
graphs of certain line objects, etc.. These have to be (on the 
plate) about half full size, and the difference between the nearest 
l>,irt and the further part is about equal to the distance from the 
camera. The enclosed rough print on blue paper will, however, 
illustrate the problem. You will notice that the camera stands 



inside a framework, and it is desired to show the details ver^ 
keen and sharp right alo«g where the crosses are ; at these points 
white labels with index lettering are pasted on, and when photo- 
graphed some become so indistinct as to be unreadable. 
A is about 1 ft. 9 in. from camera, and B, 6 it. y 
the lens is a Ross ana«tigmat about 7'5 in. focus, 
and the smallest stop F/64. It is intended to enlarge from 
negatives up to about 12 in. by 10 in. It has been suggested to me 
that a .single lens of long focus would he best, if well stopped 
down, but there is the question of spherical distortion. I have 
tried a stop of F/266, but the difficulty is to get it in the centre 
of the lens ; but if (this is the best solution, I will get a lens with 
Waterhouse stop, but wish to know before doing so if it wilt 
prove effective.— G. E. 

The problem, as you explain it, is an unusual and rather difficult 
one. We fear the only practical method is the use of an extra 
small stop. The best way to get this in x>osition is to make a 
cardboard ring that will just fit inside the lens against the iris. 
Cover the ring with a disc of black paper, and make the sto|»- 
aperture in the paper. Do not make the aperture smaller than 
necessary, as with a very minute aperture focus is spoilt by dif- 
fraction. The right size should be ascertained by trial. Witii 
regard to best lens for use, a good deal depends upon the kind of 
standpoint you can take up. If you can get far enough away, a 
lens of the telephoto type, such as the Ross Telocentric, should 
give the best result. If the print you send us is a sample of the 
objects you have to deal with, we should consider vibration a very 
probable cause of loss of sharpness during a long exjwsure, espe- 
cially if there is any machinery going anywhere near. 



Tribfkai, Appb.^^ls. — Mr. Will R. Rose, 133, High Street, photo- 
graphic dealer, applied for fuither exemption for Arthur P. Manners 
(38), passed Bl, married, manager of his Oxford branch. Mr. Manners^ 
also applied on domestic grounds. Mr. Andrew Walsh appeared for 
the applicant, and said that Mr. Manners was the only man in the 
business, which employed 31 girls and two boys, 12 and 14 years of 
age. The business supplied the Infirmary and medical men of Oxford 
with chemicals, and photographic material to University institutions. 
The real merit of the application was that Mr. Rose, who is 46, 
joined the R.F.C. at the commencement of the war, and was still 
in the Army. Temporary exemption for three months. 



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THE BRITISH 



JOURNAL OP PHOTOeEAPHT. 



No. 301G. Vol. LXV. 



FRIDAY, FEBRUARY 22, 1918. 



Price Twopence. 



Contents. 



Ex CATmsMU 15 

ttom HixxtsD RsFouu is Cos- 

MiMiUt tlaL^aaiaa I^umsBs M 
Taft Nattbs or a Divai,o»K> 

■ursoa. J. I. Cr*b«rM tT 

CoMniau ■nTsaatTT am Aaaia* 

C4Ji» m 

AMUiutn' Son* tO 

Tomtmc»mtm» riBiMiini 9B 

PtnuT Kcw* tl 



rta* 

Niw Boon .^.... n 

Mr iiun i or Boeotm SI 

CaJUUBOAL ASS U—iL IsTBLU- 

•UICB U 

Xtwi iss Mors* 94 



PUM BUM TlM MmU* Lie* 
Aiiwaa* lo Cos 



SDMlfART. 

We faggart tl»t tli* bnakiog op of old pMlor* Und (or tb* pur- 
poM of moTMung food mipplias is an hialanc avant woribv of pl^to- 
gnphic rword. (P. 85.) 



It woold aaam from raomi invaatisaAiMM w to Iha raajiiaiiiiii and 
donUitlitj of load glaaa thM tiMr* ■ faok Uttl* (oandAtMa fer Uia 
loog-ataitdiag prajodice aCHaat *• nao in ehamie^ war*. (P. 86.) 

Wa maka soma sncnatioiia with r«^ard to tha daaign of the ideal 
enLarging Untern. (r. 86.) 

The War Skraiga OMiimittaa ac« aaUnf ail anplagrar* to amoga 
a •uBoltaiMaaa B i ialMg ct w«riqpaopIa far Ifarih 6 for tba potpoaa 
o( iodncing amployaaa to ioveat in ^^ ar Savingpi Cartifleataa. (P. 04.) 

An a M to ma t ic alop that allowi of the kaa atop beiaf eomplatei^ 
npen daring focnaaing and nedocvd aa aeeaaHry daring aspoaora la 
the rabjact of • pataat. (P. 9L) 

A Mfa method <4 **ckiBg nag^ivea far tnuMBMaioa by poet i« 
dcMribwi bij • oodtoibalar to "AaaiatMte' Notak." (P. 80.) 

The United 8I«Mb OoTanunanl have a»w liaiMliiiniml Coiomhi* 
Univeraity into • phologmphie training aelioot far oCoan of the 
American Reawrw. (P. SB.) 

In a reunt cwmw nio a t aoB fron th« IwIbmi Renarcfa Lahora- 

t.n^v Vr. J. I. OMhm* giv«* the nmtkU of wtpariBMnUl t«aU on 

'9 p ro duc ed in a pyro derelopir. Be foond the depoait to 

ilmoat entirely of aaloiom ralpkiU wfaid, ondoobtedly, 

. ;U orig^Ji in the water oaed for eoMoaading the deTolopar. 

■nail qoantiliei. botiini; the water ia IIm oimpleit prFveative; 

inr iarice qaa nt i t iei tb* aalciani ia tieei i — ore d by p r aai p i t l t ion. 

(P. 87.) 

We eooment on Ike condt(ioa> th^t ooateol aactren* rfiarpncee in 
enlamBMBte, *nd Nfar to » d I ja te t i o M ytaataj m^hod. aikid to 
bMre been ioreotad by an Anartoan. (P. 86w) 

Cottinn of dry-moonrting tiaaoe .r. -ontad with a piece of cotton 
wool aoafced in torpcotine h*re h>^:, the oans* of fim in a photo- 
grapher'i worfcroooi. (P. 90.) 

Partirolara of the unaiwri— fnl .kfrpUcafUoB of an interned Ger- 
man pri*on« of war for hia di*c)..i-.-fl froa bankmptcy ar* given 
on peg* 93. 

A groop of Manchester Cnm ) 
ch«st*r SdNol of Teeknefogy tov 
drpartment devoted lo the atody of 

The P.P. A. have eleeUd • comri 
to be taken (or th* pur p o a* of »*»ii 
boeineMea who have been enlled up 

The rahject* ol devefeper poir<^r 
the " Xarkia " Us*, and plate h7fm 
on page 96. 



000 to the Man- 

f cetabliehinK a 

iietriHi ni.tn«f(enient. (P. 94.) 

t<^ to ooneider the beat eoar»e 

:as the proprietors of on*-nian 

(P. 82.r 
M^, anaatiawi v. R.R. lenaes, 
r? dealt wtU> by correspond ente 



1 

EX-CATHEDRA. 



Worthy of 
Reoord. 



Within a week or two of the present date 
ui all part« of the country events will 
be taking plaoe which, though they are far removed from 
the eyes of those in cities, mark a new era in the life of 
the country, and deserve to be chronicled by the camera. 
We refer to the ploughing and sowing of land which, in 
many instances, has not been so treated within living 
memory. As our readers in purely agricultural districts 
know, areas to be ploughed for the raising of grain are 
fixed by local committees, with the alt«mative of severe 
penalties if their decisions are not carried out. In many 
places this break with the past might well engage the 
attention of the photographer on the spot. The turning 
of the first bit of turf m fields which have long been 
used for pasture means much, and might well be made 
the oocasion of a photograph, particularly if some local 
personage can be persuaded to give it something of the 
character of a ceremony. Our friends whose interests 
are in photographic record and survey will not overlook 
UteM happenings, but our suggestion here is that ihe 
photographer in remote country places should see in these 
erenta subjects for a topical display io his window and 
for tho earning of a half-guinea or two from the illustrated 
newspapers, in which just now anything bearing hope- 
fully on the food problem ia assured of a welcome. 
• • • 

Chemical At a recent meeting of the Society of 

©••■•« GhsB Technology a noteworthy paper 

was read by Messrs. Cauwood, Turner, and Webb on the 
durability of lead glaos, more especially frotn the point of 
\-iew of it« resistance to chemical action. The special in- 
terest of this inveotigaiion lies in the fact that while 
lead glass is a renowned English specialty, there being no 
fin«r quality of glaM made for tAble purposes, yet its u^e in 
chemical ware ha<> been tabooed on various grounds that 
now aeem to havo ' - small foundation. The glasses 

tested were old »[>< ■ .ne a window gla« made in 1845 

which had been expo*ed to the weather for over fifty years, 
and the other a tumbler made in the early 'fifties. Botli 
"WA<^kad potash glasses, the window glass also containing a 
litUe boron. The resistanoe of these two glasses to boiling 
adds prove better than that of any modem chemical glass, 
and far superior to that of the much advertised German 
Jena glass. Both were the equal of modern chemical pla- 
in renstance to the action of water, and were only vvy 
slightly inferior in regard to the action of alkalies. The 
authors' summary is that lead glasses are quite satisfactory 
from the point of v-iew of both weathering and the attack 
of reagents. '" " 'ople have found Jena pla^s to be l>v 
no mwin!! v> r- '•■ i" a*»nni«l to be, while it has h v ' 

■■ ■" which tl • 
■ the wai 



86 



THE BRITISH JOURNAL OF PHOTOGRAPHY 



[Kebruaa-y 22, 1918. 



tinctly inferior to some o«bher makes, yet these two have 
been depended upon almost entirely, while the good old- 
fasliioned English lead or " fliat " ^lass has been barred 
alto^ethpr, catalogues proudly guaranteeing to supply 
.'lass' " free from lead " for chemical use. 



Enlarging 
A Secret 
Method, 



In our contemporary " Camera Craft " 
an editorial note refers to the superior 
results in the way of enlargements pro- 
duced by the Shi^man Photo Process Corporation, of Los 
An»ele.s the note forming an introduction to a somewhat 
..-.y.^rioiis article by Mr. Joseph Shipman, who gives no 
details of his methods, or the grounds that they are t.5 be 
covered by patents not yet granted. So far as we can 
rather from the article, the speci9,l superiority of the re- 
sults seems to be exceptionally sharp focus with big scales 
of enlargement, while the forthcoining patents appear to 
cover some special " attachment that can be put upon any 
regulation outfit," and which, " when adjusted, makes it a 
simple and definite matter for the ordinary photographer 
to make perfect enlargements." It seems to be some purely 
i.;echanical device, but whether it is an automatic focussing 
arrangement, or something of quite a different nature, it 
is impossible to gather from the article. In our experience, 
given good apparatus and a good negative, the chief diffi- 
culty in getting perfect focus on a big enlargement is due 
to the distance between easel and lantern. The interven- 
tion of a second person is not always satisfactory, for 
different people differ a good deal in their appreciation of 
focus, while also it is a little difficult for the man at the 
lantern to make the precise alteration that the man at the 
easel deems necessary. There is, however, already in exist- 
ence an excellent means of getting over this trouble. A 
iow-power opera-glass or telescope can be fixed in a con- 
venient position at the front of the lantern and kept 
focussed on the screen, so that the man at the focussing 
screen can get a near view of the image on the screen. 
This is one kind of attachment that can be used without 
any fear of infringing Mr. Shipman 's patent, seeing that 
it has been used for many years by lantemists, and has for 
long been a prominent feature in the optical lantern used 

at the R.P.S. 

» » * 

Sharp Enlarge- Whatever. Mr. Shipman's special devices 
ments. may be, it does not seem to us that he :s 

altogether breaking new ground in producing extra sharp 
big enlargements. The thing has been done before, not 
merely occasionally, but many times, and the various in- 
troducers of specially small cameras can all show wonder! .il 
specimens of enlargements, made from minute negatives, 
that leave nothing t» be desired in the matter of sharpness. 
In fact, given a good lens, a good illumination system, a 
perfect negative, and a quite rigid construction allowing 
of no vibration, the task is not at all a difficult one, and 
the chief reason why we do not see more dead sharp en- 
largements is probably the rarity of dead sharp negatives. 
There is, however, another very important reason, and 
that is, that only a very few people want excessive sharp- 
ness in very big pictures. The model enlargements that we 
have referred to, as produced for the purpose of advertising 
small cameras, are painful things to look at. At first sight 
they are interesting as striking eichievements, but they 
very soon become abominations if we are compelled 
to have them always in view, and even for theatre display 
IxMirds and commercial use, which seems to be the aim of 
Mr. Shipman's enlargements, we think softer and less 
aggressive results will give more satisfaction even to the 
general public. We shall be interested to learn what Mr. 
Shipman's Bpecial attachment may be, if he ever permite 
us to know, but at present we cannot think of anything 



that is not already available, and cannot quite appreciate 
the special difficulty that has to be overcome. 

* » * 

The Enlarger A correspondent recently raised the ques- 
and the Lens tion as to whether the behaviour of a 
lens in the lantern afforded any criterion of its quality as 
regards covering power in the camera. Ah old question 
this, that has puzzled many beginners. Many seem to think 
that if a short focus lens will cover a 15 x 12 enlargement, 
it is showing wonderful covering power, but the size of the 
enlarged picture has nothing to do with the matter of 
covering power at all. If we compare the lantern with the 
camera it is the negative that takes the place of the plate, 
while the enlargement is simply in the position of the 
object being photographed. Thus a 15 x 12 enlargement is 
nothing at all compared with what the lens will ' ' cover 
in similar fashion in the camera. If far enough away it 
will " cover " 15 miles as easily as 15 inches. Covering 
power, however, relates to the other side of the lens, and 
concerns only the size of the plate that the lens will cover 
at its working focal distance, which, with any moderately 
distant object, is of necessity much shorter in the camera 
than it is in the enlarger. It can only be the same in the 
latter when we are enlarging up to full size, or life size, 
which is a somewhat unusual operation. At one time it was 
the fashion to advise beginners that the best lens for en- 
larging was the lens that produced the negative. The 
advice was not quite correct, but the idea was that if a lens 
would cover the plate in the camera, it would of necessity 
cover the same plate in the enlarger. This was a round- 
about way of reminding the worker not to use a shorter 
focus lens, and a direct way of informing him that if he 
could make a negative he must possess the lens with which 
he could make an enlargement from that negative. He 
might, of course, possibly have a still better one, but the 
advice was defective in th.at it somewhat obscurest this 
point. 

SOME NEEDED REFORMS IN COMMERCIAL 

ENLARGING LANTERNS. 
In this country there has been little progress in the design 
of enlarging lanterns sin,ce the original type of magic 
lantern was adapted to photographic puxposes, Mr. 
Hume's cantilever pattern being the only outstanding 
improvement in the course of over half a century. The 
revolution which has been made in our methods of 
illumination consequent upon the general use of electricity, 
and particularly the introduction of the nitrogen-filled 
lamp, should make the way easy for less bulky and more 
convenient instruments than those now generally used. 
On the other side of the Atlantic considerable advances 
have been made in this direction, and doubtless after the 
war imported enlargers will be procurable, but it will not 
be creditable to our makers if they allow a foreign enlarger 
to oust the home product as they did in the case of studio 
cameras, in which Dresdeo, Vienna, and Berlin practically 
supplied a large market. 

In our idea the enlarging lantern should be constructed 
of metal and asbestos as far as possible. Wood is bulky, 
liable to warp and burn, and expensive to work. One can 
make stampings which require little finishing, and an 
asbestos lining is fireproof, non-oonductiv© of heat, and a 
protection against short circuiting with electric lighting. 
The lamp house, as the cinematographer t«rms it, may 
conveniently be of cylindrical form, as in one of the Ameri- 
can models, the tube being exactly the diameter of the 
condenser. This is provided with the necessary ventilating 
apertures and a bed on which the small half-watt lamp oaa 
be moved to and fro. The stage to reoedv© the negatiTe 
should be capable of adjustment bo tJiat <3iick or SHh 



Kobruary 38, 19iaj 



TH£ BRITISH JOURNAL OF PHOTOGRAPHY. 



87 



carriers could be used at will. Tfads would allow an 
arrangeoiant for tilting the negative to be incorporated iu 
ihe carrier. It would also allow of a small negative being 
brought further away from the condenser so that it re- 
ceived a greater quantity of light Uian if it were placed in 
tho usual position. In the ea~e of large lanterns, it is 
<ie~:rab!e to have smaller condeii.~eni interchangeable with 
the tull-!iited ones. It is much inor« convenient to enlarge 
or reduce from quarter-plate negatives with a 6-inch oon- 
' 'T and appropriate lens than to use an 8-inoh diameter 
-ids siie. 
The arrangement of nearly aU the focussing devices is 
ATong. We have tables of conjui^ate foci giving distances 
Setween lens and paper and lens and negative, and we try 
to [iijt theiii into praictice by moving the lens instead of the 
tK'i^ative. The new enlarger mii^t iiav« an adjustment by 
A-h:c-h after setting the distance between Imi.i and paper we 
an mov« ih« coodeneer, negative and light (all together) 
• villain a rbarp imag«. Witii «xi8ting patterns with 
wooden bede and badly fitting grooves tiiis would be 
lit, but with a well-made niotal bed it would be quite 
The beat way ot effectii cr thia would ,be to liave 
^e whol« apparatiis on a gantry or baae (the lens- 
•oard. oondenaer, and lamp-hou-i- befng capable of inde- 
:>endetit motioos tbertloti). The iron- ' dairying the 

'f>na should be ftted with an efTtcii-' p, to thai it 

vould not be disturbed when \\\v negative and condenser 
A'ore moved bo and fro for focusing. It would be an 
• rvement if the negative corner wo« detached from 
"'■'fleer frame, a few fbldn of MIoiwb intervening: 
i allow a email negati\-« to be brought forwaitl 
> a> to receive nearly the whole of tbe oone of rays from 
-he oondeoMr. 

Anoth.\- M ovetiooked by nearly all 

nakeri is i.eana of bringing any part 

>f a large negative oppusite the oeotre of the nniniMmr. 

:>!■<> was done some yean ago by the London Stereoaoopie 

■any. who iaaued a bwtk-form carrier in whicsh the 

:ive was held by frictinn l)e^ween two frames hinged 

'»ge<>her. In the quart «> any portion of a wbole- 

.!aU <v,:i Id be accurate;. '> opposite tbe centre of 

user. As it is, m ' • a little rise and fall, 

i.-^utii iiioch more sideway iM<jvtMneat. It voaU nan 



that they regard these adjurtmente as intended to move 
the projected image in the easel — not their only purpose. 
In any case the slot in which the negative carrier slides 
ehould be open at tiie tcf> and have sufficient depth at the 
ibottom to allow the centre of a 12 x 10 negiative to be 
'placed opipoeite the centre of a 5^-dn. condenser. This i.s 
■frequently required «h«>n a single figure hae toibe enlarge 
from the centre of a group. 

The length of the bellows is another matter whicb is not 
generally considered as closely as it should be. Nowadays 
enlarging lanterns are very commonly used for reducing as 
well as for the purpose tiey are primarily intended for, 
and it is very necessary that sufficient length of bellows 
should be provided for this purpose. We have adapt«d an 
ordinary cantilever pattern by making an extension cone 
to fit in place of the lens panel, thus obtaining an extra 
draw of twelve inches, but this would be much better done 
by providing a longer bellows in the first place. 

To equalise the light and to soften it so ths.t retouching 
marks and scratohw do not show on the print it is very 
desirable that arrangement should be made to interpoee 
a piece of very fine ground glass between the lamp and the 
condenser. It serves as wdl to destroy the image of ihe 
filament or InoanderHrent mantle so often evident when the 
light is in i^ be$t potation. Quite a smsl) piece placed close 
to the light is all that is necessary. When ground glass is 
ueed in this way the action of the diaphragm im reducing 
the amount of light tranamitfted comes into play. The 
area d the illuminant is increased, the grouad glass iteelf 
.being practic-ally the source of light aa far as the optical 
5y«t«n> i« oon««rn«<l. Hence the cone of raya from the 
condenser will not pate tbrcugb a comparatively pmaW 
•pertvre, but requires a large one if short eacpoeuree are 
neoeeearT. Prom actual trial with a small arc lamp it was 
found that the entire cone c/ rays emerging from the con- 
denver patecd through the condensing lens at an aperture 
of //1 6, but when a ground glaae w«a interposed a per- 
ceptible diminution of light waa apparent at about //lO. 
Trial expcMires then shoMwd that with a^^ertnres up to 
//45 tbe giving of the standard increase oif time to each 
yielded practically equal reeulta, but with additional con- 
trast, as might be expected as with ordinary camera 
•xporarca. 



THE NATURE OF A DEVELOPER SLUDGE. 



iCommnni. A'.:o So. 62 from tba Raaaaroh Laboratory of tbe Eaatman Kodak Company.) 



I •• in qiMstion was a •amp;* tafcan from a d«*p tank 

.: a pyro developer com pounded according to the 
'•Uuwtiig formula : - - 

\fetnc. Avoirdapoi*. 

I'.vro 350 grmf. 12 o«». 

Soiliiiin Mutnhite (daaic' 

c 1.800 ,. 4 lbs. 

Sod Ute 425 „ 15 Ota. 

So<l lale (desie 

f 560 „ ll'u. 4oss. 

*' ' ti^iuiii todida 3,25,, 50 gr*. 

'• 't<^r to 40.000 cca. 8] gals, limp.) 

On aUndina a fibrou* aladge pr- ' ipitated in the developer. 

• ■^ h ••>ttkd out in time, but ai;ain became diMeminaled 

' izboat the liquid on the tlightf-nt agitation. On examina- 

th« aladite proved to be rpl.it.vely inaolable in both bot 

'«!d water, and a qnantitt waa therefore thoroogbly 

' rpmove ail traces of the dav^opar, dried, and 

' I .V folkiwa : — 

(a) Lnd«T the microscope. A) irt from a little foreign 
m*'fT the sludge was aeen to '" !>.*»<I r.f '"ng tranapart"' 



prismatic crfstaU, as ahown in fig. 1 (magnified in the repro- 
duction 166 diameters). 

(b) 'A qualitative analysis ahowed the presence of calcium, 
(ulpburouB acid, a trace of iron, and someoTf^ariic matter. On 
t<<attnK for carbonic acid by trvating with hydrochlorjc acid 
and passing the gas evolved through potassium permanganate 
and then into baryta water, no trace of carbon dioxide could 



Imi I Wan 1 
(7) A qua) 



(() A quantitative examination gave the following resultfi : 

lioas at 110° C 75 per cent. 

Orsanic mat1l«r trace 

Iron traee 

Calcium oxide 31.5 per sent. 

Sulphur dioxide 35.2 per eent 

From the above it would appaar that tbe sludge in oneation 
consisted almost exclusively «< calcium sulphite, eampspondliiK 
to the formula CaSO. 2H,0. 

In order k> explain the presence af the calciam aalt, it was 
at first aasvmed that some compound of calcium liad been 
luvidentallr added to the devieloper, or that soino of tbe 



88 



THE BUTISH JOURNAL OF PHOTOGRAPHY. 



[Febi-uaiy 22, 1918. 



ingredients contained calcium as impurity, but as only pure 
chemicals were (employed it was concluded that the calcium 
must have been originally present in the water used for com- 
poanding the developer. 

A sample -of the water used in preparing the developer was 
not available. Tap water tested in Rochester, N.Y., contained 
.08 per c^nt. solids, eqaivaJpnt to a mixture of calcium and 









v^. 



Fig. 1. 

magnesium sulpliates, so that in a chalky district it is quite 
possible that the content of calcium and magnesium would be 
far in excess at this, and quite sufficient to cause the formation 
of an appreciable amount of sludge. 

The salts usually present in water are bicarbonates, chlorides, 
and sulphates of calcium, magnesium, sodium, and potassium. 
Calcium occurs most commonly in solution either as bicar- 
bonate or as sulphate, and according to the following solubility 
measurements the concentration may be as high as .2 per 
cent. 

Solubility of CaSO. 211^0 at 18° C. = 2.016 g. per litre 
(Hulettand .Vllen, .X .4 m. Chem. Soc. (24), 1902, j). 674). 

The .solubility of calcium bicarbonate depends on tlie partial 
pressure of carbon dioxide in the water, and according to 
Treadwell and Renter (Zeit. Anorg. Chem., 1898, 17, p. 170), 
when the partial pressure of the carbon dioxide is zero, water 
at 15° C dissolves .385 gm. per litre of calcium .bicarbonate. 

In order to determine the preci.se method of formation of the 
calcium sulphite the following experiments were carried out : — 

1. On adding a solution of sodium sulphite to a weak solution 
of calcium chloride, or calcium sulphate, a precipitate wa.s 
formed of calcium sulphite, but not in the presence of an 
excess of srxlium bisulphite, owing to the formation of the 
soluble calcium bisulphite. With a saturated .solution of 
calcium bicarbonate at 18° C. no precipitate was formed. The 
further addition of an excess of sodium carlwnate gave an 
immediate precipitate if much calcium was present in solu- 
tion, Imt not with a concentration of .25 grams calcium chloride 
(fused) per litre, and with the concentration of the sulphite, 
bisulphite, and carbonate the same as that in the developing 
formula above. On allowing the solution of calcium bisulphite 
to stand in an open tray for a few hours, prismatic crystals 
separated out similar to those shown in iig. 1. 

According t" Weis.^erg (J, F. Pr. Chem. (2), 1871, p. 119), 
calcium sulphite has a solubility of .043 grams per litre at 
18° C, but this dis.solves in an excess of sulphurous acid or 
in the presence of stxlium bisulphite forming calcium bisul- 
phite, and on allowing Uie solutiou to stand in the air six-sided 
needles, having, tlie composition CaSO, 2H,0 are deposited. 

2. The rilxno experiments were repeated with a magnesium 



salt (magnesium sulphate), though no precipitate waa obtained 
with sodium sulphite, sodium bisulphite, or sodium carbonate 
when using solutions of a concentration equal to the concentra- 
tion of the respective salts in the developer, nor were crystals 
formed on allowing the bisulphite solution to stand in an 
open tray. This is as would be expected from the following 
solujbility figures: — ■ 

Solubility of MgU^., 6HjO at 20° C. = 12.5 g. per litre 

(Hager,' Chem. Cent. Bl., 1875, p. 135). 
Solubility of MgOO, in a solution containing 23 grams of 
sodium carbonate per litre = 0.29 g. per litre (Cameron 
and Seidell, J. I'hys. Chem. (7), 1903, p. 588). 
The concentration of .s<idium carbonate in the pyiro formula 
above is such that any magnesium present up to a concentra- 
tion of .25 grams per litre would not be precipitated as car- 
bonate or as sulphite. Therefore, even though the water used 
for preparing the developer contained magnesium either as 
sulphate or bicarbonate, none of this would be precipitated, 
which explains tlie absence of magnesium in the sludge 
examined. 

Effect of the Presence of Sodium Carbonate on the 
Possible Precipitation of Calcium Carbonate. 

From a consideration of the solubility measurements of 
calcium carbonate and calcium sulphite in pure water, the 
carbonate being less soluble, it would be expected that in a 
developer containing carbonate some calcium carbonate would 
precipitate out along with the sulphite, although the sludge 
examined did not contain carbonate. This may be explained 
in two ways. 

(o) If the sulphite and bisulphite solution was allowed to 
cool in the tank before adding the carbonate, crystals of calcium 
sulphite would tend to be deposited, which crystals would not 
redissolve again on adding the sodium carbonate. 

(6) That calcium sulphite is less soluble than calcium car- 
bonate in a mixture of sodium sulphite and carbonate of a 
concentration equal to that in the developei-. Although no 
precise measurements were made, on adding an excess of 
calcium chloride to a solution cijntaining 50 grams sodium 
sulphite, 10 grams sodium bisulphite, and 15 grams of 
scxlium caribonate, the precipitate obtained consisted largely 
of calcium sulphite, with only a trace of calcium car- 
bonate. This is explained by the fact that calcium 
carbonate is soluble in a solution of sodium carbonate 
forming a double salt, having the formula CaCOj Jsa^COj 2H2O 
(Barre, Compt. Eeml, 154, 1912, p. 279), A rough estimate of 
the solubility was made by adding a solution of calcium 
chloride to a 1.5 per cent, solution of sodium carlionate (which 
is the same concentration as in the developer above), and it 
was found ixjssible to add .125 grams of calcium chloride to a 
litre of the solution at 20° C. without precipitation. 

Although a number of trials were jnade, by compounding 
the complete dev^eloper according to the formula above with 
water containing .25 grams calcium chloride (fused) per litre, 
in no case were crystals deposited on standing. If water con- 
taining calcium in excess of this was used, a white sludge con- 
sisting mainly of calcium sulphite was deposited, though this 
was not of the same fibrous nature as the particular sludge 
under consideration. It was considered that the needles could 
only have crystallised within the complete developer, providing 
the same was mixed very warm, a procedure verj' unctesirable 
in the case of pyro, owing to its propensity for oxidatioii. 

A Method of Preventing the Formation of the 
bludges. 

In order to prevent the formation of the sludge, it is neces- 
sary to remove tlie calcium from the water used in compound- 
ing the developer. If the ^5alcium is present as bicarbonate, 
in whi<h case the water is temporarily hard, the hardness may 



Fabrauy 22. ISIS.] 



THE BRITISH JODBXAL OF PHOTOGRAPHY. 



89 



• stroyed by Uto well-known method of boiling, when the 

r:oaat« is deoompo6«d and calciam carbonate is precipi- 

' > -: The " fur " which depo«ita on the iiuide of kettles is a 

!;>: iliar example of this. In case small amoants of developer 

hare to be mixed, the simplect vay of removing the calcium, 

thire>fore, it to boil the water and allow it to cool. Incase the 

:-i under consideration precipitated oat from the solphite 

bisulphite solution before adding the carbonate, previous 

".i of the water would prevent the precipitation of the 

:■-, though as this procedure would only remove the calcium 

one-twentieth of the volume of the solution, in the event 

'■ sludge crystallising out from the final aolution boiling 

1 be ineffective. 

When fifty gallons or more of developer are to be mixed, it 

is not feasible to boil this and allow to cool again. The 

<-alcium may, however, be precipitated either as carbonate or 

• 'X^late, when present as bicarbonate, chloride, or sulphate, as 

! ■ •*» : — 

A. Precipitation with todiiun cartenate. Add a dilate 
•ohition of sodium carbonate to tho water contained in a tank, 
until DO further pvecipitate is obtained, or the carbonate may 
(••■added to the water so as to make a definite stock solution, 
s ty 2 per cent. The precipitated rarfaonate will settle cni «*ev- 
iiight. when tba dear sapvraatant liquid may b* deeaated. 
Not all the calciam is refflorcd in thi* way. (Solobility of 
<aCO, at 18° C. -.012 grams per litre), HoUeman, Z. PAy«. 
<'Aem. (12), 1893, p. U6, though the amoont left in eolation 
i« not sufficient to cause the formation of a sludge of calciam 
•ulphite. 

B. Precipitation as oxalate. ' Tho calciam may be mors oon- 
pletelv removed hy means of sodium, potaasiom, or ammonioB 

•wing to the fact that xalate is more in- 

A n calcium carbonate. . of calcium oxalate 

0069 grams per litre at 18° C.) Kokiraasch aid Boas, Z. 
I-hyi. Ck4m. (12), 1893, p. 241. 

A solution of sodium oxalate is added until no farther pre- 
<ripitation oocurs, and the sohition decanted after allowing to 
aettla T«aU showed that sodium uzalaU had no effect on the 
fogging power of the developer when prearat even to the extent 
of 1 per cent , so titata little azocss of oxalate daring precipita- 
tion will do no harm. 
SrMMAST.— If the water nssd for eompoanding a dewdoper 
' ' - ; sodium bisulphite or potaasinn metabisalphite con- 
' > ^ I. lam in aolution to the extant of tha sqnivalent of 
026 per cent, dry calcium chloride or mow, fine needle-shaped 
' r%*uls having the formaia (TaSO, 2H,0 are apt to lepaiate 
.i* a aladfeoa sUnding, and espadally if the sulphite and 
'■•-tiiphita aolution ia allowed to stand bafors adding tha car- 
bonate. The fludce is hannlees if alkmad to aeUla, as it 
liaidens and forms as a scale, though tlie developer ia robbad of 
tulphita to the extent of the amoaot rcquirad to lom tha 
nlodx^. If the developer ia sgitatci, the sludge it apt to eaoae 
troable by settling on the emulsion •>( the plates or films, though 
It may be r e n o va d Ly filtering. 

In case tlia oalcnim is i>rr«eni .is biearbonata, thus oansing 

temporary hardness of t the formation of the sladge 

f'^v be preven'-^' * ' *- ,..„ ,.: j-aier and allowing it to oool 

lout to •' :ig thi> •I'AoIoper. If the calciam ia 

■■-^•nt ri^ ' ..iiliV.' -..' )i case the water it 

I in.!!.- • !, . ., V prvripatinj; with 

• i carbonate. The 

r ■ . :.■ .^ ..: .,: . :. :, . .ryhardness. 

* intiubted t» Mr. A. 1'. 11. Trivelli for the photo- 
V '/wn in Fig. 1. J. I. rniBTiiBE. 



Fur Or-nrc Sorri— p~i-.. ■ v — i..;- j , ,. , be_ 

I ' - •.-•••!. 1 1.- .■ Imperial 

* ■-,{• <«i .S^.i*j»cr •ml 1 »«r,Tn«»if'gv ■ w uvrn r^» riwt«*i r^resident of 
' • Optical Saeisty. 



COLUMBIA UNIVERSITY AN ARMED CAMP. 

Four Thousand Officers of Reserve to enter Goveriunent Mililary 
Bcbool of Photogr^hy. 

Columbia University took on something of the appearance of an 
armed camp after the middle of January, for then began to arrive, 
in squads of one hundred at a time, four thousand officers of the 
Reserves to learn the most advanced methods of aerial and land 
photography, and cinema operations. 

The United States Government is actively poshing its campaign of 
education of the masses and its war photographic work, and has 
accepted the offer of Columbia to make use of its resources for teach- 
ing military photography in all its branches. The school, however, 
is to be managed solely by the Government, which determines also 
the personnel of both students and instructors. 

Only persons who understand the difficulty which has been ex- 
perienced in projecting photographs which have been filmed by dif- 
ferent makes of moving picture cameras can appreciate the object 
of the Government in aasembling four thousand men to study cine- 
matography, as well as " still " photography, at Colombia. The 
Govemmaat has orercome the principal difficulty in yerfejt cinema 
operation by standardising everything connei't<>d with its cinema 
work, and wants those olBoert to become accustom jI to the Govern- 
ment eqaipntsat, so that pictares taken by different cintmatographcrs 
OMjr be piojstted without a flaw oa the same icraen. That U.e entire 
work may run with smooth precision upoo the screen, men will learn 
St the university not only how to take moving pictures, but how to 
develop, cut up and ssssmble filais, and how to project them in 
theatre or camp. Not tba least important lesson will be bow to 
pack and ship films, so that those takto by a cinematographer in 
the front line treocbcs may be lafdy transported for development 
in the rear. 

Ths seops of the work is such that the University has had to. 
provide a projection room, laboratory, workrooms, and Ucture-halls 
oa the campus, as well as darkrooms, and the customary appliances 
nsrtsssrj for ths study of still photography. These demands have 
rtsolted in a tcattermg of Government work through different build-, 
in^, with the basement of Uavctneyer Hall as main inttrucUng room. 
This spacioas floor has a fine north exposure which supplies ideal 
light for photography, and Monday, January 14. saw the inceptioa 
of this first GovtnuBsnt school of military cinematography in 
America, and lbs conversion of the seat of learning into an army 
post. 

The poet is limited to the Government's activities, and embraces 
aa administntiiva force of 125 officers. When detachments of 
sittdenta arrive from their respective camps, they will find themselves 
under military discipline no less than befori-, with the gsy tempta- 
tioas of Broadway nearer in distance but not in attainment. These 
men bavs bsan drswn from various regiments, because they have 
tome knowledge of photograpby, and instructors have been engaged 
to develop this knowledge for military purposes. 

Soos idea of the Government's appreciation of camera work as a 
war msMiirt may be gathered from the fact that men will be trained 
to take still pictures as the airship volplanes to a height proved best 
for pictar»4aking. This altitude, of course, subjects both pilot and 
'• i-T-mVrg 'T'v*'' to the risk of being hit by aerial gunfire ; and when 
the pilot Tolplsnss downward to the required level in the air he 
trusts to good fortune to assist him in making a safe as well as 
rapidaaeaps. 

"^fg^Bn aayviag picture propaganda the aim of the Government is 
twofdd— to educate the American public in what the nation is doing 
with our soldiers abroad, and to instil in the minds of soldiers in 
camps, where the films will be exhibited, an even greater patriotism. 

At Columbia the war photography work is in charge of Captain 
J. Sears, assisted by Lieutenant Carl Gregory anj five or six aides, 
with offices in the Library building. The University has, indeed, 
without fanfare of bugle or beat of drum, become an armed camp, 
an established army p<:)«t, with 125 officers in charge. 

A plan 's under way to add a School of Navigation, to train officers 
for our growing merchant marine, with Professor Harold Jacobgr, 
of the Astronomical Department, at the head of it, and it is 
rumoured that an Aviation School is soon to follow. 

Up to the present time pssteta-by have become accustomed to 
seeing 200 marines and bluejackets from the School of Engineering 



90 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[February 22, 1918. 



drill in the North Court, and some 350 men in khaki drill at night 
by aearcMight on the Athletic Field ; but only now has Columbia 
bucome an Array po»t and taken on a military aspect. The military 
students in the United States School of Cinematography will find 
their routine of camp life maintained by drills in South Field, and 
sncii regulations as prevail in barracks. In this case the barracks 
are located in the main floor of one of the University buildings, and 
the studentofficers police their own quarters. The posting of 
sentries has been decided upon by officers of this new Army post, in 
consultation with the SuperintMident of Buildings and Grounds, and 
the patrol of these has caused Morningside Heights, accustomed to 
the, sight of drills among students, to open their eyes and realise 
that one of the oldest seats of learning in the country is the most 
advanced Army post in America. — Scientific American. 



Ji$$i$tatit$' notes* 

— • 

Notes by assistants suitable for this column will be Miuidtred 
and paid for on the first of the month following fublicatien. 

Sending Negatives by Post. 

WSKN negatives on glass have to be sent by post, as is often the 
ca^ when the photographer employs outside help or for other 
reasons, some means of secure packing in otder to prevent any pos- 
sibiility of breakage has to he devised. To send glass negatives 
through the pest packed in cardboard plate-boxes is really much the 
same thing as packing a fragile piece of eggshell china in wood wool, 
and doubtless many plates are broken during a year, and much extra 
trouble and annoyance caused by the fact that the long-felt want 
for a really good strong and simple negative box has not been filled. 
We used to pack all our negatives in small wooden boxes, naUing the 
lid down with small pins. This served until one of the plates got 
crocked, through the jar of the hammer, and this led us to turn our 
thoughts towards the production of a method of packing that would 
prevent any such a recurrence. Thinking that our methods may be 
of interest, and, we venture to hope, of jjrofit to fellow readers of the 
"6.J.," we describe them herewith. Nothing very startling in the 
way of originality can Ibe claimed for these methods, but we can 
iissert that we have never had a cracked or broken pUte among many 
sent through the post in this way< and, further, we would point out 
that if the " cases'" are properly made, there is little chance of this 
happening. The first case we shall describe is for use when two 
or three negatives only are to be sent. Take two pieces of fret-wood 
or' cigar-box wood about an inch wider and two inches longer than 
the size of plate in use. Then take another piece of wood of the 
same size about three-quarters to an inch in thickness, and cut away 
from its centre an opening only about l-16th of an inch wider than 
thie plate. This opening must then be extended by removing one of 
the ends, as Fig. 1. Two pieces of stout felt, such as are used by 





jVe^atwes 







O 


O 







\ 


\ ° 








e 


■ O 



Fig. 1. 



Pig. 2. 



liuuse furnishers for putting under stair-treads, and which can be 
bought for a few pence, are next required. These should be cut 
slightly smaller than the plate, and fixed by " Seccotine " in position 
to the two flat pieces forming the main parts of the case. This is 
best done by adjusting them after the cut-out frame (Fig. 1) is in 



position. They should then be put aside for the adhesive to get 
thoroughly dry. The case may then be put together by screwing 
with 3-in. brass screws to the cut-out frame. A piece of strong tape 
Bufiicient in length to go right round the longest way of the caie 
should be firmly fixed in position inside the top of the latter. The 
case is now complete. To use it take the plate or plates, which 
should be wrapped in a piece of clean tissue paper, and push them 
down into the case, pressing the tape down with them. The purpose 
of the tape is now apparent. By a gentle pull the plates will be 
drawn to the top, and may then be withdrawn from the case. Tl^e 
open end of the case is best filled with a piece of wood cut to size 
to fit the opening. A couple of holes are bored through this, and 
also in the same position in the top of the case. The Ebp may be 
tied with string through these holes or a couple of small brass bolts 
and nuts may be used to keep the plates in position. The negatives 
will be found to be quite firmly held. A sketch of the case, with the 
plates partly inserted, is shown in Fig. 2. 

A more elaborate case for negatives is one that has also the advan- 
tage of being very easily made from an old dark slide of the book-form 
pattern. The centre-plate, or card, is removed, the shutters glued 
into position, and the projecting ends cut off flush with the rest of 
the frame-work. Two pads of felt are then glued over the draw-out 
shutters, and the job is complete. This will hold two or three nega- 
tives without fear of breakage. 

When a number of plates have to be sent a very simple and easity 



^^ 



Pig- 3. 

formed case is shown in Fig. 3. This consists simply of a felt-lined- 
box just large enough to take the negatives comfortably. They are- 
held in place by the lid, which is simply a piece of wood, also felt- 
lined, which is held in position toy a couple of old springs from a 
printing frame. It will be thus seen that by the elasticity of the 
felt and the action of the springs the plates are thus fii-mly held in 
position. One point more we may add, and that is the plates should 
always be packed fairly tightly, for the less they move about the less- 
risk there is of cracking or damage. — Expebt. 



FORTHCOMING EXHIBITIONS. 
February 16 to March 2. — Edinburgh Photographic Society. Sec., 

P. T. Mackintosh, 38, Castle Street, Edinburgh. 
February 21 to 23. — Leiceeter and Leicestershire Photographic 

Society. Sec., H. C. Cross, 80, Harrow Road, Leicester. 
March 12 to 15. — Hackney Photograpihic Society. Sec., Walter 

Sedfe, 24, Pembury Road, Clapton, E.5. 
April 18 to May. — Hampshire House, Hammersmith, Photographic 

SadeAy. Entries close March 19. Sees., H. T. CaUender, 10, 

Acre Lane, Brixton, S.W.2; or W. T. W. Sliiers, 201, Gdldhawk 

Road, London, W.12 

m 

Tribunal Appeals. — ^At Portsmouth, Mr. F. G. Allen appealed 
for the general manager and operator of a firm of photographers, 
who were doing valuable voluntary work for the Ministry of Food. 
The appellant was thirty-seven years old, classified C3. He had 
made a special study of X-rays. He was granted conditional exemp- 
tion, on condition that he joined the Volunteer Field Ambulance. 

A Waening. — A member of the P.P..\. had a fire break out in his 
workroom on two different occasions, and in neither case could the 
cause be ascertained. ■ They might have remained as unexplained 
mysteries had not a third fire been traced to its source. Gutting? of 
dry-mounting tissue had been thrown into a tub into which was 
also thrown a pledget of cotton wool soaked with turpentine which 
had been used for rubbing prints. The result was spontaneous com- 
bustion, and it was practically certain that the previous fires had' 
been caused in the same way. — -Circular of the Professional Photo- 
graphers' Association. 



WeitTMuy ir, iaiH 



THt liKinsU JOLKNvVL OF PHOTOGRAPHY 



91 



Patent Reios. 



COMPLETE SPECIFICATIONS ACCEPTED. 
Thtm tpeeifieatums are oUainaiU, jtriee 6d. each, pott free, from 

the Patent Offiat, iS, Strnfttampton BuUdtngs, Chancery Latts, 

London, W.C. , ' ' 

fti4 date in brnckets is that of apptieation in this eouniry ; or 

etbroad, in tiie case of paUnt* granted under the intentaJtoNoi 

Co'itvntion. 
\' -...MATic Stop is CAMXaAii ~\o. 108,458 (Augnut 2. 1916|. 
I ' r liiiary cunrnM thv leiw dj-ruire U ad)<utMi > :u 

tlir light And to the •ensitiTenecg ni the pUte*. In ri-: .is 

it u f reqaently ne c ewafy to have a large Una aperture. The reafoii 
for this k that with a anall ap«riur<' it is impoaeible to focua rery 
•harply. as the picture appear* to ' ■■ dull. Evfo when the 

oiijeci It lighted Tery brilliantly ' ,. . :l- on the gruund glaas 
•crean does not appear any more diiitinet, for the eye ii blinded by 
thr rtrong light ontaide. It ia, however, better to uae a Bnaller 
•{wrtare when the li||it conditiooa are favourable, aa thi* molta 




til a great* aharpDae* But tha om of a anall aperture ia diflknlt, 
for the reaeooa alAled. 

Thie invention aima to remove thcaa duadvantagca. Tkta ia done 
by using a *top, which ia to arranged tliat, iasmcdiataly before the 
oxporare of the plat«. th« aperture ia Mitably ledooad, wher the 

' a! plana ahattar ia releaaed by the ftrntu* of the flngcr. Thr 
• ' >< u preferably an iris di»f>hnktfTn. with the diHerencn that 




Fig. 2. 

:t i< compUiely opened doriag focussing, and, aa aoon aa the mirror 

•'■''■ -ea to a previously determined smaller apertorp. 

K.-ii. 1 «:!!_.■,, ibo atop cooplvU'Iy open daring fncuaaing, and 

: .' rn 2 the atop with ledaead oprmriij during axpoeare of the plate 

f .«.• (ignraa, a ia the eupport <.f the atop, b a slot in which th«- 

be moved and looked. .\< will be aeen fmm the diviaion* 



.-.. in th» 
.tfierture f 

r,, ..f ik- . 



aaaoffleJ that thr Irna ha* a 
ia aet ao that during the ex 



.iwl 



tt has ) Ti 

lat thr rtop 
■ .torture i« '8. 
• dt8plir.i.:Mi is determined by an aim </ 
,f A to'H.iH* the atop c, but is at flrat held 
r. 1\> I'., uawl is ronnrct«d thr relrasr 



..lion g, so UjjI jii»t before thr lr»er which con- 



trol* the movements of the mirror and of tlie exposure slot of the 
rsuoera oompletes its mov»™-"' ■< fnrre.'; the pawl r back into the 
iiott«>d position and thus .i' arm il. Under the action of 

the spring A, th? arm d eiig„^v» .>,Ui the previously adjusted stop c. 
as shown in fig. 2. 

The chief advantage of the invention consists in the fact that. 
o» ing to the nie of a very large 'aperture -when focussing, a strahfri X 
lighted picture, but not verj- sharp, is obtained on the ground gla.««. 
and focussing can be effected verj- conveniently and exactly, wliil.<t 
the photographing is done with an aperture suitable to the light 
conditions. This avoids over-exposure, and at the same time the 
lack of sharpneae of the objects which are not in the exact plane 
of the pictnre'is reduced or done away with. The invention cnnld 
be equally socceesfully applied to those camera* in which the focus- 
sing is done on a ground glass plate. Friedrich Treitechke. 9, 
Heikendurfer Weg, NeumQhlen, near Kiel, Germany 



Reu) BookSe 



M. Per 



The Rabeiyat of a Photo|(r«phcr. By Aonic 
Ix>ndoo . Heath, Cranlon, Ltd. Is. 6d. net. 

KmconuL^'s rendering of Omar Kbavyam has had many parodistf , 
who, with greater or leie auoceas, have sought to reproduce the 
elusive metre of the poem, and, aa is the essence of parody, to 
extract humour, by applying the old Persian writer's maxims and 
reflectiona to some mndern cult. Many of Miss Parr's forty-oight 
stanxaa embody mure of tliis kiud of humour, and at the same time 
preeerve the charm of the original metre more faithfully than other 
psrodire which we can remember. Here is one which needs no 
explaoalioa : — 

The Lens no Qaeation niakea of Eyes and Noae, 
But draws thr Caat or Squint in spite of Poae ; 
But he who fakee the " Negt. " and finished Proof 
He knows about it all — Ue knows. He knows. 
Another of a quartet relating the realised effort to get h print 
hung at one of the annual exhibitioiK is : — 

And when I sped in Eager Haate to T^wn 
To aee the Pictnrea by the Saton sh^u. 
And in my Joyous Emiid reached the 8[K>t 
Where Mine made one— they'd hung it upside down. 
Many others will rijually appeal to thoae who have made photo- 
graphy n hobby ; they will thank the author for having made avail- 
' > book than which none could be more welcome as a 
"Oe photographer to another in place of the stereotyped 
gtccttiiga, such aa cards and calendars, which are preserved only 
until a state of mmd is reached in which they can be thrown away. 

FiodiBt a Fairy. By Carioc Cadby. London i MilU and 
9eoa, Ltd. 2s. 6d. net. 

WntM .Mrs. Cadby wrote, and Mr. Cadby illustrated, a story calleJ 
the " Doll's Day," they endowed children with a fund of joy in 
following the adventurea of the three dolls who for one day came 
alive and fraternised with rabbita and squirrels in the woods whilst 
their yoang mother, in a levenlh heaven of delight, looked on. We 
are quit«> sure that the finding of a real fairy alive in a wood will 
be jual aa fascinating a theme for little people aa the romantic per- 
"THlMVaa of the dolls. Like the previous book, the atory, in the 
ryes of the child who reads it or to whom it is road, gains immensely 
in realism by the exi ■cdingly clever photographs by Mr. Cadby, 
who siviws the little ht-roine Eve on her travels of discovery in the 
woods. It is a sturj-lMNik for children which can be read again and 
again with endless delight. 

Motioa Picture Education. By Ernest A. Deoch. Cincinnuti. 
Tkc Standard Publishing Company. Two dollar*. 

Like other volumes by this auUior, the present one consists of a 
srriaa of short papers, having the appearance of having been sepa- 
rate brief nwitributions to magazines and here brought together in 
book form Om- rmiri.t help having the feeling that such a subject 
aa that which is suggested by the title of the book needs to be 
dealt with in a more ordered way. However, there is a mass of 
fact and suggestion in the author's 360 pages of text, and thost^ 



92 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[February 22, 19ia 



who are engaging upon the uphill task of harnessing the cinemato- 
graph to real education in this country, in place of allowing it to 
be apenl upon the stupidities of the picture theatres, will find 
plenty of argument and many good precedents in Mr. Dencli's 
page*. 

Rabi Tbchkicai, Books. — We are glad to find that the exigencies 
of the time in the matter of paper supply have not prevented 
Aleatre. Henry Sotheran and Co. from issuing their customary cata- 
logue of rare and standard books on scientific and technological 
subjects. The new list which just reaches our table runs to 250 
pagee, and includes works on all branches of science and technology, 
and is valuable not merely as a cjitalogue, but as a ibibliographical 
guide to the date of issue, form, etc., of the many rare books which 
it includes Photography is classed in Section IX., under the 
general heading of "Chemical Technology." It is interesting to 
note that among the very old text-books of photographic methods 
Messrs. Sotheran have a copy of the original manual, issued in 1839, 
on the Daguerreotype process, which is now extremely rare. 
Another old French book is that by Gaudin, a writer in the 'forties 
of the last century, and a pioneer before, his time in the evolution 
of a dry-plate process. Still another French work is that of Le 
Gray, a forerunner of Scott- Archer in the invention of the coUoJion 
process. A feature of such lists as Messrs. Sotheran's is the inclu- 
sion of reprints of papers read in their day before the learned socie- 
ties. One of these which is listed id that by Sir John Herschel, 
'• On the Chemical Action of the Rays of the Solar Spectrum on 
Preparations of Silver," a paper which first announced the use of 
hypo as a fixing agent, and apparently originated the terms " posi- 
tive " and "negative," as they are now emiployed in photography. 
The catalogue, which is supplied by Messrs. Sotheran from 140, 
Strand, W.C.2, price 23. 6d. net, will be welcomed by all with any 
claim to a wide reading of scientific subjects. 



meeiinas or societies* 

— > 

MEETINGS OF SOCIETIES FOR NEXT WEEK. 
Saturday, Fkbbuary 23, 

Hodd-rBfliild NatursUat and Photographic Society. " The Philosophy ot Slang.' 

J. H. Qreen, M.A. 
Stalybridge Photographic and Soientiflo Sooiely. An Evenine with the 

Microscope. 
Edinburgh Photographic Society; Exhibition Lecture, "Rome." T, Shaw. 

MoiTDAT, Febdcaky 25. 
DewBbnry Photograpbic Society. Eihibilion ot Members' Prints. 
Bradford Photographic Society. " The Homes and Haunts o( Worisworth." 
S. JLDnd. 

Tuesday, Febedaby 26. 

''°''!'.'v.^\°'f*''*P''''' Sooie'J- "Round about Graemere." F. Humpherson 

"Nicholas and Napoleon." B. C. Wickison. 
Birmingham Photographic Society. "The Book of the Dead." Isaac 

Jirsdley, J.C. 
Hanlsy Photographic Society, Y.M.C. A. Architectural Slides. 8. A. Cntlack. 
Keighley and Diitrict Photographic Association. Yorkshire Union Exhibition ot 

Selected Lantern Slides. 
Hackney Photographic Sooiely. Experiences and Opinions ot Members. 
Manchester Amateur Photographic Society. Photographic Parliament. 

Wed.vesday, Pkbhcary 27. 
Croydon Camera Club. "Travellers' Samples." F. Aekroyd 
.,f"j°l,?''°""'"*{'!'''' '^'l'''- "Some Hidden Beauties ot Nature." F. H. Stevens 
Illord Photograpbic Society. " Exchange End ot the Telephone." A. F. Hills. 

Thursday, Febecaby 28. 

Liverpool Amateur Photographic Association. "Eastern Wirral, from Birken 
head Priory to Stanlaw Abbey." T.J.Smith ""»<!u 

Hull Photouraphic Society. Y.P.U. Portfolio : Egyptian Slides. 
Stockport Photographic Society. Lecturettes by members. 
Hamracramith (Hampshire House) Photographio Society. "One Man Show." 

Bodley and District Photograpbic Society. Members' Night. 



THE PROFESSIONAL PHOTOGRAPHERS' ASSOCIATION. 
A MBETiNO of the Council was held on Friday, February 8. Present : 
Messrs. G. Hana, A. Basil, Gordon Chase, A. Corbett, C. F. Dickin- 
son, A. Ellis, S. H. Fry, R. Haines, N. N. Speaight, Lang Sims, 
F. G. Wakefield, H. A. St. George, A. H. L, Chapman (Swansea), 
P. Lankester (Tunbridge Wells), T. C. Turner (Hull), and 
Alex. Maokie 



In reference to the National Portrait Gallery, it was announced 
that a question would be asked in the House of Commons at an early 
date. 

In reference to a complaint tiat had been received from a non- 
7nember who had sent the Evening News 7s. 6d. for a colour- 
graph enlargement, as advertised, and although the money had been 
sent in October last the enlargement had not been received, a num- 
ber of letters sent to the coi]9,plainant by the Evening Newt was 
read. The Council agreed upon a certain course, and the hon. 
secretary was instructed thereon. 

A complaint having been received from a photographer that a 
competitor in business was displaying as specimens of his own work 
copies of photographs printed in a certain publication, the hon. 
secretary reported the action he had taken. 

The hon. treasurer reported that the accounts for the past year 
had been duly audited, and would be issued to members, with the 
notice convening the annual general meeting. 

It was decided to invest another £100 in War Loan, making £600 
in all. 

The matter of a new arrangement for fire and other insurances was 
discussed. 

'i'he Lang Sims Scheme. — Mr. Lang Sims reported that he had at- 
tended a meeting of the LBusiness Man's Association, an organisation 
founded for the purpose of assisting proprietors of one-man businesses 
who had had to close their businesses on account of joining H.M. 
Forces, to reinstate themselves in business after the -war. The chair- 
man of the meeting referred to the fact that since the scheme had 
been started various trades liave formed organisations to effect this 
purpose, to apply to members of the respective trades, and sug- 
gested that instead of working independently, these separate organisa- 
tions should become afiSliated to the association. A committee was 
formed, upon which Mr. Lang Sims was appointed, to coneidor the 
course to be taken. 

Among the new cases were two ae to the relations of the applicants 
■with their respective landlords; one as to the liability of the 
applicant under the Shops Act ; one as to the obligation to pay wages 
to assistants absent through illness. The progress of various cases 
in the solicitors' hands was also reported. 



CROYDON CAMERA CLUB. 
Mr. B. T. Rose, last week, was down for a chat on how he 
constructed and fitted up his darkroom at home, and all who know 
his predilection for system in everything, anticipated rightly that 
the darkroom would be a well-ordered aSair. 

Like that of the professional, the amateur's darkroom variee 
largely in space and convenience, the modest cupboard under 
the hall staircase being on the lowest rung. Frequent acci- 
dental encounters between the head and the stairs render this 
improvisation suitable only for those of professed morality, 
otherwise visdtors ascending to the floor above may be con- 
siderably astonished at the sentiments wafted from below. 
Still, such a cupboard far exceeds in size the mid-Victorian 
portable darkroom on wheels, or tent, in which collodion platea were 
coated and developed by photographers on tour. The upper part of 
the human anatomy entered it ; the lower did not. Celerity in mani- 
pulation was desirable, for asphyxiation threatened from within, and 
without there was the danger of a triple combination, represented 
by a small boy, a stout pin, and an uncontrollable sporting impulse. 
After all " boys wUl be boys," the dear little cherubs, and the con- 
ditions ensured them quite a respectable start in the subsequent 
sprint. And then the mystery attaching to the smell of the ether, 
giving an alchemistic touch to the operator, who, in those days, had 
to be a craftsman in the true sense of the word. Now, thanks to the 
plate and paper makers, exposure-meters, or what not, even the 
average member of a photographic society can turn out decent photo- 
graphs almost automatically. To tliose who become swollen with 
pride in the process — and some are so afflicted — a course of wet collo- 
dion is confidently recommended as a remedy for technical flatulence, 
though, unhappily of no avail for that peculiar mental distension du» 
to excesses in pdctorialism, which in grave cases may be followed by 
artistic delirium tremens. A very sad example recently illustrated 
this. 



Ftbrauy 22, ISiaj 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



93 



Bat we are leaving Mr. Ku-<e to bluom unheard. As a matter of 
fact, though he bloeaonieii in every dirtvrtioii, the flowers were hardly 
toitable for gathering to form a rrp-it. a state of things not alto- 
gether new. A wonderful model of his darkroom, complete in every 
>let.iil, was greet«d with murh laughter and applause, and the many 
c-otitnvances explained aroused so niiioh intereet that supplementary 
leituree sUrted in various parts of the room, occasionally drowning 
th." main theme. Another time the n-wly elected cigiirette-smoking 
president (Mr. Catharine) must ex.i. -e more authority. His pre- 
decea«)r invariably indulged in n example which might be 

followed as tending to inspire tor the chair. True, the 

adjacent secretary used to complain t, •.-. ily of nasal martyrdom, but 
this was doiibtleas due to the prejiid:.,. of a pipe-smoker. Besides, 
It takes years to become acclimatised t.. tlie ameU of some cigars. 

Out 1,1 the many tips given we .».l... t .,ne. Carriers for the enlarg- 
ing lantern were shown constructed .it of strawboard, a material, 
.Mr. Rom said, which never warped .md lasted well. The novelty 
consisted in the lum-^Mtnns, which consisted of ordinary piiis 
driven thn.iieh the strawboard, aixl then bent at right angles by 
' -■ '» 'he ajierture of the carrier, the ends of the pins 

.pped off. .\ very neat and useful idea, as the usual 
. r«niK.t be atUched to itrawboard with screws. In 
' .^• -.on which preceded a mjwl heariv vote of thanks for a 

'• Mr. Keane ■ - .urn mended linoleum 

■ dne board, on „ ..| that it was " iuex- 

■''" •■«." Any attempt l« reason out a concrete 

"^'•' rding <,f l]::f .taieni..t.i hid better not be 

attempted. 



Commercial $£eflal imelllaence. 



A i;gaMA> BAXKkUiT's Ai-ii.i.ATloN-. M the Lunduii 
Hankru|,Wy Court on Tuesday l.i.t an adjourned applica 
Uon was road, fa- the dac^mrge of Aagnsi Ernst (k>tU>eb 
nu^Mmi. the Priaoom' of War Camp. rnrnc-M^. N„,thant. 

lately . .•rrying on busiiieas at ' T . » 

:r:«i,!.:. .|..jler. Mr. J. H. Kii 

I Se .|.-i.;. .1 *.!.« I,r..i. . ■ 

T)>. ■■Ih. .; ,, 

• in .lune d, 191b. uii . 
to raitk against the > ' ,:, 



•.irt. 

ini: "fdei -was nade 

• e^ipected 

- .t £2J68. 

KOd DO asseU were disck«ml by ll»- i..iiknt|>l atid nothing had lieeii 
realised. The bankrupt was a <>.<mian s«bjec< at presrat in sn 
■ntemaent aMa|i. In IflOO he left < irrmany fur Pans, where he was 
•«ipluji«)l as a trBTelivr unbl IT'S a fien h,. ,..„.. to this country 
^»lth a capital >4 aboot £100. I „ mi a«re«nent 

to art ss agent un cooUDiasioi f.ssrs. CteMr. nf 

Berlin, a firm of pbotognphi. -nh an .,tfi, .. ^t 9. K.rr 

ikt^M. Avenue, K.C. He then £SOn i., Crrmau Iwnkcrs 

■<ad oibers. which » irr agenctc* (or 

Ovfoaa hmses deal . .Kxle. and gaU- 

tine. He ivjw owed .Vle*>ni. .\rii<li i of Wandsbek 

£S26 : Memirsi Curl .in. I l\.-i,tiju MeMrs. Nncel 

>"■' *"•••■! 'Ury and go<jd< 

rectiM-.i ••:. Ih, . - —lunted to 

The debtor's ledger. r jmrt of 

snmunts, had Iwen lost. ■,..;.. ,,,;it he drrn 

froa his bosinaas fur salary and p<-i .srs the sum of £400 

a year, which far exceeded his pr- - U lieii w.-,^ ' it lir 

foand that nobody vuiild trade n t)i him, and m r 14, 

1914, he transferred his assets t<> i company re- >i<'re,i .u .\. 
TlKBimnn and Co., Ltd., with a noin.iuU oapitai of £1,000 in £1 
4ham. He was appointed man - ' -ector and secretary of the 

•^onpany at £104 {ler stiinam .. week lor exjienses. The 

he assigned to the o.in|. >ted of the gu<Miwill of his 

rained at £200, ami il ' -'"<'k-in.trBde, furniture, etc.. 
V- h ba valaed St £»». He .< .. 'ns fully i ° ' 

'■ ooOlfMny and ilisrhari.'e all ' detits sihI 

I'-: ■• - ..■■ ' -..Is t., the ■ 111 

I . thill he llo|><-'l 

'o make tcinij with hn lh'.^\du aii.l ' i inun creditors after the war. 



The debtor at the time was being po-essed by his creditors and was 
hopelessly insolvent, and, after the transfer of his assets to the 
company, was entirely without means to meet h:g liabilities. The 
bankrupt was unable to give any adequate reason as to why he was 
Ukely to be more successful in trading as a, company than in trading 
as a private firm. In December, 1914, bankrupt met the petitioning 
creditor, to whom be agreed to pay £3 per week in consideration 
of his receiving an interest in an invention for a new periscope, hut 
the invention proved to be \-aIueless, however; he was sued by 
the inventor for arrears for salary, and, judgment having been 
obtained against him, the bankruptcy proceedings ensued. Bank- 
rupt alleged his failure to have been caused through the stoppage 
of his business owing Ui Ihe war. to kMs on Stock Exchange ^)eculn- 
tions, and loss on exploiting the periscope invention. One of the 
chief causea of the bankrupt's insolvency, however, was the transfer 
of his business as.«ets, valued at £1,000, to the limited company 
under the circumstances stated. Amongst the crediUvrs of the 
bankrupt were six linns in Germany, -whose debts amounted to 
£873 in rewpeci of goods and money received, and whidi bankrupt 
had aupropnaled t'> hi« own use and beneflt. 

The' official receiver had been jirevented from communicating 
with the creditors in (Jermany, and consequently was unable to say 
whether the baidiropt had been guilty of fraud as an agent. Under 
these circumatancee the official receiver submitted that oonsidera- 
ti.Mj of the bankrupt's application for discharge should be adjourned 
until after the concluKion of the war. At the outbreak of war, the 
bankrupt, a« alreadj stated, t««na(erred all his assets to the oom- 
pany, leaving himself entirely without means to pay his creditors, 
bat whom he alleged the company would pay. The bankrupt was 
hopetesaly insolvent at the tima he transferred those assets, and 
did not consult any of his creditols before making sodi transfer. 
.\fter Iha oonpany was formed the bankrupt drew out ai the com- 
pany's fund £840, of which he sent £m to his wife in Switxerland, 
and the remainder be spent either on himseK or on enterprises in 
which he was interested. Subsequently the bankrupt sold the 
■*\v,\r of his shares of the company to his lady t)i>ist and expended 
the money. In Xovemlwr, 191S, the bankrupt gave a bill of sals 
over his huusebuM furniture in consideration of an advance which 
,,: rxi,riim*; consequently the debtor denuded him- 
of his aaMa. 

I iidvr the fuirgoing circumaUnces the ofBd^ receiver submitted 
that the ileU<-- had l>een guilty of miscondoA in relation to his 
aff. r. iii.Munu.h as wIk-ii he was insolvent and unable U> pay his 
delit. a. Ihev bec-oroe due, and without the knowWdge ami mnsent 
„( hu. . re.litoni. and without obUining an indeiwiident valuation, 
he tniii.ferred the whole of hU asseU to the company. That the 
K -id ako bern guilty of miscoodtjot in having entered into 

w . uler. bv niiNins of a fictitious loan, a certain bire-porAaae 

• Kreemenl in order to .hfeal Zeiglers crediUiri. Debtor purported 
to leii.l /-eigler £125, and m consideration of this Zeigler purported 
t.. sell l« the debtor his furniture, but the debU-r admitted it was 
a Uvii* tranwcton. The official rei-eiver further submitted that 
the Uiikrupfs asseU were not of a vahie of 10s. on the amount 
of hi. uiuiecured crvdiU.r.. The debt-.r admitted having traded with 
a knowledge of his insolvency, and he furtl«-r charged the debtor 
with having contributed to his bankrujitcy by rash and hazardous 

*''Th"e'eJmed Registrar, in giving his decision, said it was a difficult 
and snumm case to deal with, because, owing U. the war, the 
relatioiikbetween debU.r and certain firms in ilemiany, to whom he 
owSr'nSnev. oMild not be properly iiivestigaUHl. It k»ked as if 
the debtor 'had been guUty of such misi-oiiduct as to amount to 
fraud Under those circumstances, even if there were nothing else 
in the official receiver's report, he should feel some doubt as to 
whether he ought now to deal with this application. He proposeil 
to adjourn the ai/plication, mainly on the ground of miscfinduct. 
and hesbouW adjourn the application for two years from the present 
time, in the hope that the war would then be over, and il might be 
then (M«*;ble lo communicate with the foreign creditors. When 
-• came on in two years' time, and he decided to suspend the 
• discharso. it would date from the day upon which he made 
h.., .„ '.ition, but he would give (fcbtur liberty lo apply 

ii an •■ if at any time he could satisfy the (Jourt in regard 

to those U<i;isa£lions. 



94 



THE BiUTISH JOURNAL OF PHOTOGRAPHY. 



[February 22, 1918. 



ReiDs and Rotes. 

— ' — ""♦' — 

Tbadk Marks.— The Trade Marks Committee of the Federation 
of British Industries haa decided to oj^jose Part 2 of the proposed 
new Government Bill " To Amend the Trades Marks Act, 1905," on 
the ground that it will inflict serious injury on the owners of per- 
lectly legitimate trad« marks. Part 2 deals with provisions for the 
prevention of abuses of trade marks. It has also been decided by 
the same committee that the proposed British Empire Trade Mark 
should be opposed. 

Fleet Street Photoorapher as Officiai, War Photographer. 
— Secand Lie.ut. A. Console, a well-known London Press photo- 
grapher, has just been appointed one of the official photographers by 
the War Office. Mr. Console commenced his photographic career 
with Messrs. Kodak, Ltd., as a demonstrator and instructor. Leaving 
them for Fleet Street, he soon after received an appointment on the 
staff of the " Daily Mirror " ; for many years he acted as their special 
correspondent in many parts of Europe, including the Tripoli cam- 
paign. In 1912 he made a balloon flight over the Alps from Inter- 
iaken (o Upper Bavaria, covering a distance of 300 miles and reaching 
the altitude of 17,500 feet; he also descended inside the crater of 
Vesuvius, the second time on record that a descent has been safely 
attempted. He holds a certificate from the Swiss Alpine Club, 
granted for making a record descent of Mont Blanc, the previous 
holder being a German. During the present war he was attached 
to the Italian General Headquarters as a special correspondent. In 
1916 he left the " Daily Mail" to join the A.S.C. Mechanical Trans- 
port, and shortly afterwards was appointed instructor and lecturer 
to the A.S.C.M.T. 

A Business War Bonds Week. — A strenuous effort of business 
men to promote the sale of National War Bonds and War Savings 
(;erlificates is to be made during the first week in March. Employers 
of labour are asked to adopt an instalment plan (if they have not 
already done so) for the purchase of War Savings Certificates which 
has been found to be so eminently successful. The Hon. Organiser, 
Mr. Wareham Smith, asks every employer to arrange a meeting of 
his workpeople on Wednesday, March 6, at 12 noon (11.45 where 
luncheon hour is fixed at noon). The urgency of the matter in rela- 
tion to victory should be explained to the workpeople, and type- 
written slips' prepared beforehand should be handed round showing : — 
1. The instalments which the employer is willing to accept. 2. Space 
for the amount of War Savings Certificates desired by the employee. 
3. Space for signature of employee. If, therefore, the employees' 
investment in War Savings Certificates, added to the employer's 
own in National War Bonds, are registered on Thursday, March 7, 
the enemy will learn the cause of the strange silence of our industries 
between 12 and 12.30 on the previous day. Those able to co-operate 
in this scheme are asked to advise Mr. Wareham Smith, National 
War Savings Committee, Salisbury Square, E.C.4, so that he may 
forward their acquiescence to the National War Savings Committee. 
New Lectpreship in Industrial Management. — A group of large 
firms engaged in the principal industries of the Manchester district 
have offered to the Governing Body of the School of Technology the 
sum of £3,000, spread over a period of five years, towards the cost 
of establishing a new department of industrial management. The 
Manchester Education Committee have recommended that this gift be 
accepted, and expressed their high appreciation of the donors' public 
spirit. It is proposed that a lecturer shall be appointed for this period 
of five years, at a salary of £600, to conduct research in the subject 
of industrial management, to organise a new department, to lecture 
to members of the University and to the public, and to assist indus- 
trial concerns in the solution of management problems. To make 
doubly sure that the department shall keep in close touch with prac- 
tice, a number of managers, directors, scientific experts and others, 
who have had special experience or are responsible for important 
innovations, will be invited to deliver public lectures, being offered 
substantial fees, which will not only pay them for placing their 
knowledge at the disposal of their fellow-managers, but serve to 
encourage enterprise and experiment in matters connected with 
management. These lectures should be of assistance not only to 
future mamigers, but to those already in that position; they will 
strengthen the idea that management is a science, and that every 
manager is, or should be, something of a scientific researcher. 



Corresponaetice* 

— « — 

. • Corresp<mdents should never write on both aides of the paper. No 
notice is taken of communications unless the names and address** 
Of the writers are given. 
'.* We do not undertake responsibility for the opinions expressed 6y 
our corresvondrnts. 

DEVELOPER POISONING. 
To the Editors. 

Gentlemen, — Your correspondent, Mr. Jas. Dunning, seems to 
imagine that I am oilt for every poor bromide printer's blood. "On 
the contrary, I merely stated my experience in the hope of helping 
anyone who is afflicted rwdbli the scourge of our profession. 

I do not indulge in " ladies' journals, " my complexion being 
good in parts like the pre-Aviar curate's egg, but I hav« a super- 
sensitive and absorbent skin, which requires drastic remedies to 
cure. 

It is a feeble argument to state that the application of menthol ■ 
or citric acid to a wound causes " unbearable pain." Certainly 
there is a " nip " on apipilying, but I contend that that is just what 
is wanted, as it cauteitses the wound, just as a doctor would heal 
certain septic wounds by cauterisation. It is a case of being cruel 
to yourself to be kind. 

I may state that Mr. Dunning's surmise as to the source of my 
information is entirely erroneous, my informant being like himself 
a " Membeir of the Pharmaceutical Society of Great Britain." 

Mr. Dunning merely repeats my advice (to apply to hands before 
starting to work) when ' he states that the trouble can easily be 
prevented if precaution is only taken. And his suggestions about 
cleanliness, hot "water, dry well, etc., are reiterations from previous 
letters in the " B.J.," and only a fool or a child need have them 
pointed out. Moreover, his camphor recipe is somewhat reminiscent. 

The formula I sent may not be the one in the Briti&h Pihanna.- 
cqpoeia for rheumatic paiin, but it healed my hands after years of 
suffering, and that is the salient fact which other sufferers would 
do well to note and, I trust, benefit by. — Yours faithfully, 

Alloa. CM. Foster. 



ANASTIGMAT v. RECTILINEAR LENSES. 
To the Editors. 
Gentlemen, — ^The articles you have published and the correspond- 
ence on the circles of illumination of lenses will have served a go»d 
purpose at the present time if they lead photographers to realise the 
qualities of some lenses which now He stored away in cupboards. 
If one were huying a lens for aU purposes, the choice would naturally 
be a good anastigmat, which has capacities beyond the rapid recti- 
linear both in working aperture and covering power. But a big 
price must be paid both in money and in convenience of working 
for the lens with the superior corrections, and now that rapid 
rectilinears are a drug in the market a battery of them can be 
obtained for the price of the anastigmat, and each lens of the battery 
— used within its capacity — will probably equal the anastigmat in 
performance, if not always in rapidity. 

A 6-in. anastigmat with an angle of 90° gives a circle of illumina- 
tion of thirteen inches. Used on a quarter-plate it contributes one- 
fourth of the light it passes to the making of the picture and three- 
fourths to the fogging of the plate. It is true that the unwanted 
three-fourths of the light can be cut off by a hood. That is another f 
way of saying that the very qualities for which a larger price has ' 
been paid have to be sacrificed to the obtaining of a clear picture, 
and that by methods which are bothersome in actual working. I 
should prefer to use a lens of ordinary angle for the generality of 
work and a wide-angle lens for extreme subjects, and the two could 
be procured to-day for very much less than the anastigmat. 

Are not photographers making a fetish of this correction of 
attigmatism? That is the whole point. Astigmatism should 
not show in a good rectilinear until a comparatively wide angle is 
required, and corrections in a lens -which only show outside the 
angle of the picture taken, while scientifically interesting, are of no 
practical value.— I am, yours truly, 

Alfred H. Watson. 

26, Morpeth Mansions, Westminster, Feb. 18, 1918. 



February 22, 1918.] 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



95 



PLATE SIZES. 
To the Eiitors. 
Vuur remorkx. as well as titoe* bv a c»rrn»|xindfiit, 
,. The new .^Joerican 11 by 7 size would certainly be 
uf sarti'ice lu sinti^e-figure portrait urv. aa there ia uodoubiedly a 
kit of waste wh«n llie ■taiidafd and -H wtaMWiwl aiaea are naed. 
Standard auMa are more square than many workers unagine, bat 
»r havf become so acenstoraed to them that we do not perhapa 
• • •> sqoarenMS. I have often heard the 5 by 4 siie con Jeroned 
uw square in shape, but wv still go on tuing the 13 by 10, 
which is eren inoi* square than the fmaUer sire, a fact that may 
be proired ky mathenoticia or diagrams. Pot in another way, the 
12 by 10 haa the pfoporiiona of a plate mescnring 5 by 4 1-^— if 
my OMthoda of ealco^atioo be eormit. 

Tha aooanpaaying sk<4ch shows a{>|>roztmatcly the sqoarenera of 
(he orthodox sizes, A B C O in a true square. A 12 by 10 taJcea 
ap the area of the aquare as shown £ B F O, and using B D aa the 




«id« for all tha aia» and radodng tlirm to a given height th« 

. .1 :^ : . ,|«) (MDa to about tha poaitiooa — Hrid. thna one amy ••• 

.>.>«• how fha sqna r t n am diminiaiMB and bow imnow the 

I : >,> 7 and 7^ by 5 axes ara eonpared with the whole, half and 

■> .rter platas.— Youn faithfully, 



O. Woaov. 



INK. 



THB M^ 

To ti ._. 

flenUemea,— Raading in tha " B.J " of Febmary 8 " Smm Naw 
KmU *nd RTpprimenta on the ' Ma-' - ' f - " by Mr. A. Lockett. 
ro..i;r,l t.. my mia4 som eipertm ,r to Mr. LorkeU's I 

'I. I f.ur . - ■ ■ • — n aco. I was iiuu engaged Op 
' "" ^ 'f ^'n• and after ioiagaa ^foa the 

• .f i,i„ 'AfirriuMota I BotireJ that, when a dar^ iii.j.it .los 
'■ .1 '.iKin a light bMkgmuid. Ih-re waa always a lighter line 

• --en the two. Thia lad ma to try and find out why aoch ahoold 
- '>e case ; and. thiaUag tha theory foud might be of Mne inte- 
r«i to your readers, I am sendios it along. 

It ia la be rinsiuliutd. fir«t of «ll that an image of the object 
' lol at is fonnad upon the - .wntm of tha ntsnia— < < 

. t .n of tha eye asoaiUi'e t-. .ch rods and cooea secrat^ 

.( .4 known as " viaoal porple.: j hu M OMd ap when an objert 

. ■«•<» »t intently for soma iiW^li.reartld^JB an "after image" 

••eing formeJ, and which can be distin. tiy aaan if the ey«a be ckacd. 

Iha ftiat Ihaocy, then, waa thai the imag* pMtly oTe'rlappwl some 

• th., foda oMaide those mad by the image, and used up the risoal 

■]■> sacfetod. 

I appeod a iiagram to make my meaning claar. 



: I 

3 

4 




I »l.e len.. e< ih, ,,^ Q. the object, 1, ». »aga lonned upon 
• • rod. 1. a. J, 4, 5. 1 and 5 bring rtl4i of wkieh only haff ar. 



Aka im age formed upon 



heini: used to receive the imai;e, resulting in the whole of the 

\i>ual purple" therein being used up. 

However, I abaudniied this theory, as I foinid that, upon with- 
drswine the object .10 as to produce a smaller image, which woulj 
at oue place or other form an image upon whole rods oply, the 
li);htpr line was seen all the time. ► 

The second one is, I think, nearer the mark— i.r., the eyeball is 
ne\er still, but o«;»llating all the time, rceultMig in the image being 
partly on one «et of rods and then on another set, this going on 
backwards and fonvards all the time the "visual purple" is being 
used up, and the after image produced is projected, and surrounds 
the object. 

Contrast certainly jilays an important part. To any of your 
readers who intend trj.iig theae experiments I would reoominend 
their also trying with oolonred objects, when Uie complementary 
coltur of the object will be seen.— I am, j-oura faithfully. 

Fredebic G. Tritton. 

18, Archibald Road. Bamfield Road. Exeter, 
February 11, 1918. 



Answers ro Corrcsponaents. 

— ^ — 

SPECIAL NOTlCa 
'm tunttfutnet of fttural rtd ute d tupplUs of paptr, a$ I ht rttmU 

of frokMiiem »f He imp onaiionof mcA wood pulp arui frau 

a tmalUr rpae* wiil t e ■— i VaWs mUU fwrtJUr noliee for rtpl%t. 

In rarr ttp omd tnU 
Hfftr, ft will antwtr ty yosi if Uamped and addrattd ewe 

Up* is sa nf sss d for roflf i S-«tmi In Umoiional eoupon. from 

readari ukro a d . 
rko faB faHtows mnd amowort witi b* printed ontf in Ik* ntt of 

i»fmrim of y wiral <a««rail 
Qasrtas la U •mtmtrtd in lAa Fridof't " Jonmai " was* reaat m 

mM laUr ikan Tuudof {potttd Mon dof), and thomU t» 

arf^rsssed lo lA« Kditori. 

^- B.— Try W. Botcher and Sons, Ltd., Camera Houae, Farringdon 
Avenue, London, K.C. 

a, BAKNt. — Tha hypu uema to be of full strength, and not to coii- 
tein anything injurious. We do not think that you need worfy 
aboat the colour. 

Rumcm Pt-m..— Thcta are no aabools of photography in London 
wbew anaagementa are nad« for reaidenta. About the beat school 
is that of the Regent Oti ea t Polytechnic, the management of 
which haa a special bureaa for the purpose of finding sinlaible 
aoeoOBDodatinn for ladiea who ocane op to town fur the course of 
iaatraoiioa. 
Rmowjujio. — Tha idea is to employ the Braaso as a local reducer, 
uaing a small bit of waah leather or oottoo wool to rub down denser 
parla. If it leavea any grvaaineas, a rub with petrol, benzole, or 
turpentine will leave the surface clean enough to take the medium. 
Aa the polish Muo<.ilhs the surface of the film you will not find the 
medium take quite so easily aa on the natural surface. 
*J -^g tt — \l) The lenses of this make which we have tried have 
DMaol exorllent quality. (2) They were made by a German firm. 
Srhnltae and Billerbeck. (3) Anastigmats are very scarce just 
now. Anything up to three.quarter liet price. (4) You must 
form your «»wn conclusiona. Qet the lena on trial. (5) The firm 
IS n»iw known aa StaJey, Shaw mid Co., 88, Newman Street, 
Oxfr.rd .Street. (6) Yea, it f/ll ie raf>id enough. 
Stommu Puow — Is there any advantage in storing plates in a 
cupboard, or will they ke<^ equally well in a room? Ia a eold. 
dry room belter than warm ? — M. B. 

It does not matter where you store platea so long m they are 
ke|>t from hght. sulphur fumes, and damp. A cool roosn, if dr^ 
!• Iwtter than a warm one. Keep them out of the fames from 
>ul|>hide of soda if you nse it for toning broroi lee. 



96 



THB BRITISH JOUKSAL OF PHOTOGRAPHY. 



[Fobniary 22, 1918 



Ybxow 8T<m ox atOMW Pmkts — We should cay Uicae are apbah 

marks, and that the ferrotype plate* have been splaafaed with aooae 

■ bleacUng chemical aolotion ; from the colour we sboold snapeet 

ferrieyanide, or perhapa a bleacher of ferricyanide and bromide. 

II DO iolnUon. of this kind are about it may be that the Frendi 

>.1..H, u contaminated in lome way. If waahing the ferrotype 

plate* doea not atop the tronble, we should try new chalk and 

new platea. 

LiGRHM HI PoKiBJUTTM.— Your trottUe U due to the white dia- 

temper. Corer this with aomething iaik and yon will find a great 

improvement Ton may use a small movaUe reflector as needed, 

and a areolar head-screen to further control the Ught. Yoa can 

get a good deal of rarietv in the Ughting by taming the sitter 

aitay from the U^t and working the earner* aomewhat out of the 

centre line of studio. Always remember that it i* only the lig^t 

that is a fixture. Neither the sitter not the camera is screwed 

to the floor. 

D G.— We do not imderotand what you idmui when yoo say yon 

are trading in your own name. Your etotionery Aows that yon 

are trading as the " X " Stndios. In these circumstancea you 

nquire to register, and to oomp!y with the rules of the Regia- 

tiatioD of Bnaineas Names Act in the way of legibly marking all 

your stationeiy with your real name. Where von seem to have 

gone aatiay in your mind is by tbiaking that yoo can t n^ under 

a fancy name so long as you pot your real name on your atitiooery. 

Bat that, by the Act, you an prohibited from doing mleas yon 

register. 

Ttnre nt Bbomdm.— Why ritoold prints on " B.B." paper, toned m 

ammcminm sulphide, vary in ookrar, some being a blue-brown 

tone, others ydlow? This is aft« the prints have been through 

two hypo bath* for ten minutes, and washed aiiteeai changes from 

dish to dish. — ^B. L. 

The difference in colour after toning is nsuaOy due to variation 
in the time o( devel<^>roent. If yon expose for as short a time as 
will give a good print and develop for two minutes, you will get 
a deep brown. If you over-print and derelop for fifteen or twenty 
seconds, yoa will get yellow tonea. 
Acn> Fixnc Baih.— Can you hdp me in the following ?— I use tank 
developing and fixing. The formula for fixing is :— Hypo, 
70 lbs. ; sulphite soda, 5 Ibe. ; glacial acetic acid, 4 pinla; grd. 
alum, 5 Ibe. ; water, 35 gallone. Dissolved in order given. Films 
and plates are fixed for half an hour, and bath is streogthened 
periodicafly. As you know, the price <rf diemicala is now very 
high. Can you reoommend an alternative bath that wouU answer 
tlie purpose, or ooold we use some oUier add in place of the acetic, 
whi^ is now on expensive item and difficult to obtain ? — W. R. 

You might substitote half a pint of pure sulphuric acid for the 
acetic acid, and also leave out the alum, which is hardly neoeesary 
for plates, especially at this time of the year. Dissolve the sul- 
phite and hypo separately, and then ad 1 the acid to the sulphite 
solution before mixing. 
LiCHTniG THE Snnno.— I want to follow " Practicos's " hints about 
ligbUng studio, which he gives in an article a few weeks ago, and 
as my new studio is 15 ft x 8 ft., I think the standard electric for 
lighting will suit all right. Where can I buy the stand^d with 
fittings for 3,000 c.p. half-watt lamp, and also what kind of 
reflector is needed for shadow side of studio, and where to get 
same, if you think I should best have three of 1,000 half-waU 
lamps instead scattered, as per Practicos's plans? Please oblige 
by enlightening. — L. A. S. 

Yon can procure all fittings for half -watt lamps themselves from 
the General Electric Company, Ltd., 67, Queen Victoria Street, 
London, E.C. Ask for booklet of Almos type. For a small studio 
the single standard light is convenient, but is rather more difficult 
to manage than a number of lamps of the same aggregate power. 
In any caae, you will find a small circnlar bead-screen a great 
assistance in controlling the lighting. Any ordinary studio 
reflector may be used. If you have not one, a light wooden frame, 
about 6 ft. high and 3^ ft. wide, covered with white paper, with 
a strut back, will answer very well. 
Halt- Watt for EmjiSOSR.— Is the J^-watt electric incandescent lamp 
a suitable light for bromide enlarging? If so, is it made in any 
form whidi could be conveniently used in a ^-pl. Cantilever 



pattern enlarging lant«m? The ordinary bulb is far too large. 
Failing this, is there any other form of electric light — other than 
an arc— oo the market which would anawer as well tor this par- 
pose? What candle-power do yoa advise? — ^A. K. D. 

There is a q>ecial form of lamp for this purpose, the filament 
of which is a wire spiral fixed in a circle about an inch in 
diameter. The bulb is about three inches in diameter, candle- 
power 200. As the lamp is recommended to be used with the fila- 
ment in a horizootal position, it would be advisable to fit it with 
a 45° mirror below, so that the areolar aa|>ect of the filament is 
preseoted to the condenser. Write to the General Electric Co., 
67, Queen Victoria Street, London, E.C, stating your requirements 
aul Uie- voltage of your sui^Iy, for particulars. The only other euit^ 
able lamp would be the Nemst, but t^e filamraits are rather frail, 
and expensive to replace. 
Eklabcisc. — ]_ Yon can easily find the correct position for negative, 
lens, and plate for enlarging to any desired size by employing the 
ordinary rule for finding the conjugate foci, whidi is that the 
greater conjugate (lens to paper) is the focal length of the lens 
moltiplied by the number of timea the image i* to be enlarged, 
phis one. The lesser ocojiigate (lens to negatiTe) is once the 
local length of the lens, plus the focal length divided by the 
magnificatioa. Thus, to enlarge 1 in. to 15 in. with a 4-in. lens 
requires 4 by 16, or 64 in. lens to paper, and 4 by 4/15 in., or 
4 4-15 in. lens to negative. If the bellows of your enlarger 
will not close up sufficiently to enable you to use your 4^ lens, 
you most have a sunk front fitted. The same would, of ooarse, 
apply to the 6-in. lens, or, as an alternative, you ooold use the 
7-in. Homocentric, and allow 112 in. from lens to paper, and 7 7-15 
lens to negative. Measure from the diaphragm with either 
of tfaeae lenses. 2. None of the stains you mention will affect the 
image; if you want a deep tint, an old pyro solution will give 
you a good colour. We assume that the oak stain is a dye; if 
it contains any pigment it will not be suitable. 3. It is impos- 
sible to answer tiiis positively. As a rale, a negative taken with 
a soft Ibcas lens will yield rather too fuzzy an enWgement, bub 
all depends on the degree of nndiarpDees of the negative. If yoa 
are using a flat field lens on the enlarger you can soften the 
definition to any desired extent by judicious focussing, even with 
the sharpest negative. 



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THE BRITISH 



JOURNAL OF PHOTOGRAPHY. 



No. 3017. YoL. LXV 



FREDAY, MAKCH 1, 1918. 



Pbicb Twopekce. 



Contents* 




..rti .c. . ! Ill 
—1 ti; It^ II,. 

ihim at MMM tiBW ^r t>. 4.' rr. < 

Am mtxtrU imU^ 



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«• a fairit la^p 




i» w a WK norar ponraiMn mm* «d*M« oo focMami, 
••"i tistitin^ of Ilk* utur vIB W faaiy «• |ut« 97. 

fmac. a twfoi Mlaqpac mml. aSa ftra 



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ia*. 






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Mr Oun 



«• Ow 



Mis Wtt9 9WWfttn|[ 

m " A— m to 



'^4 no pagr 106 
!• lfM»-Trt« p<'. 



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cUaao oa nmn 104 



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IU>U<' 



n4 yi«|ac«<ir. k *• 
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iiTT»Tit fnaU}ix«M of lh» •• TVwnnia Prvtio '" of ooloar 
■H tha ma ht-ftltOT* tt* wtt ia thr 

n* fitn .-M aod ntbar foraw of 



EX-CATHEDRA. 

Mirror We were recently inspecting a number 

****'^'****** of portraits by different workers, among 

which were Mreral wiiich showed the reflection of the sitter 
in a mirror as well as the direct image. In *ome instances 
the resulu were quit* pleasing, but in others the poor show 
made bjt the reflection quite spoiled the effect of the com- 
poaition. Mention of a few points on which mistake^' were 
made may aave others who essay this style of work from 
committing the same errors. One is connected with focus- 
•ing and th« iena aperture. It must not be forgotten that 
the reA«ct«d image is not on the plane of the silvered sur- 
face of the mirror, but as far behii^ it as the real object 
is in front of it, therefore the focn ■■■•-* '- ' ^ ; •• 
aa to Mcure as e\-en a degree of 

may b* deaired, a much smaller aj^nure i>»-iiig uecessai 
than when the figure alone is taken. For the same reasi . 
tlM aitt«r must not be too far from the mirror. If that is 
•o. not obIt will the aperture ha%-e to h^ r^,„^ till a long 
•tpowr- ;it the T< appear too 
■Dall. fh^ f\^, ;j of rather 
short focaJ Jeog^ r to be found in the 
lighting. Ver>- _ licli is most suitabl« 
for the 6gure is not so for the reflection, or vic« versa 
where a full fa<-e and profile are to be t'hown it is usual). 
•driaabl* to let the profile appear in the mirror. Car- 
mint b*' •-'"" " •' - —fleeted light from thp 

mirror ■. Finallv. the po»*> 

miut be 5111-11 : .iceful and well 

bklaoecd. both (jnation The 



truw any ; 

should be k. 

a slight inclination may be advantageous. 

• • • 

Th« Car* of An av«nue for leakage, 
•'****•• '-a"*** may be of serious 

which is very usually appreciable, is to ).. 
jKMsrelcw' war in ' ' 
MOOn of monnis, . 

might ^ a uiiali 

prr«»r)' of all n 



which in some 

II. but 
II tiie 



th 

ojv ' , e: 

cent, above pre-war pnc««, yet how many are left in hroken 
package* to get «moky and dustv before they are nex* 
rvqoirad! Every sire of mount should have {{■• own well 
cloeed stock-box. *o that when a package is opei':''' •'■- — •■ 
tents can be at once transferred to it : the cl. ! 

boxes used by draper* and stationers answer \\e.[ ror 
mounts, and the boxmakan will readilv make any special 
to fit existing tbelves or pigeon-holes. Sensitive plate^ 



'Je 



TILE BEITMH JOUBKAL OF PHOTOOOaAPm 



[Maacli 1, 1918. 



liud papers are also best preserved in special boxes, a good 
and safe form of which is like the old-fashioned pull-off 
cigar-case, one section sliding into the other from the end. 
The plates may be left in tiieir own box for purposes of 
identification ; the store-box being large enough to allow for 
thia The method of preserving is especially useful for 
large sizes, which are not in everyday use, and frequently 
are found in a doubtful condition owing to the damaged 
state of the packing. Great care should be taken to store 
all sensitive plates and paper well away from where there 
is any risk of sulphide fumes reaching them. Vapour of 
this description rapidly causes black edges on bromide 
paper, and metallic markings on plates. If possible the 
iulphide-bath should always be used where there is a good 
.iraut'ht to carry away the obnoxious fumes. With regard 
to chemicals, it is perhaps only necessary to say that these, 
even if purchased in paper wrappings, should be trans- 
ferred to boxes or bottles as soon as received, while those 
of a volatile nature should be kept in stoppered bottles. 



Why 

" Enlarge- 
ments " P 



A recent niimber of a Transatlantic 
contemporary gives a very, useful tip 
to photographers who wish to sell pic- 
tures of a larger size than the usual cabinet. It is simply 
to use enlargements without announcing them as such. 
The prospective sitter is shown prints in various sizes and 
the order booked in the usual way. If the order is for 
the cabinet or a smaller size an enlarged proof is sub- 
mitted when the finished prints are delivered; this is 
usually purchased, and not infrequently further large 
copies from the same or other poses. The freedom of 
modem plates from blemishes and the excellence of the 
lenses used mak-es it easy to produce enlargements up to 
two diameters which require no " working up " in the 
ordinary sense of the word, and which bear no evidence 
of being other than contact prints. For a good class of 
business a print — black or sepia — may be made on cream 
crayon paper with a narrow masked margin, this is 
mounted on a rough drawing paper, which, by the way, 
is now easier to obtain than most tinted mounting papers. 
The masking is easily done while enlarging, and if the 
mask is fixed upon a glass plate hinged to a card back 
there is no necessity to make pinholes when fixing up the 
paper. 



New Method ' In the " Journal " of the Optical Society 
of Silvering of America, a new and very valuable 
Mirrors. publication from the point of view of 

those interested in optical matters, Mr. Otto StuMmann, 
jun., describes a new method of making mirrors, applicable 
in the case of any metal, and to any material, varying from 
glass to paper. It is described as a distillation method, and 
the principles are simple, though the apparatus needed is a 
little complex. Briefly, the process is as follows : To produce 
a silver mirror on, say, glass, a horizontal silver wire is 
heated to incandescence by means of an electric cun^eiit, 
and the glass to be silvered is placed about one inch below 
it. The whole apparatus being in a vacuum, the wire is 
drawn at a uniform speed backwards and forwards across 
the glass, which is covered with a uniform coating by the 
descending metallic vapour. With small objects, such as 
galvanometer mirrors, a row can be arranged uiidei* the 
wire and treated simultaneously, the operation being com- 
pleted in about one minute after the necessary vacuum has 
been obtained. It is claimed that either opaque or semi- 
transparent mirrors can be produced with equal ease, the 
thickness of the coating being determined very simply by 
the time given. Seeing the great difficulty there is in get- 



ting really good mirrors by chemical processes, it would 
seem wortii while to give this new method a trial. 



The Pseudo Mr. Lockett, iu a recent article, referxsd 
Mackie Line. to the fact that an effect similar to the 
so-called Mackie line is frequently noticed on photographs, 
as the result of an optical illusion. This, however, is not a 
new observation, for when two different densities come into 
sharp juxtaposition they always seem to be falsified in some 
way at their mutual boundary. The phenomenon is akin 
to the effect always observed in plate-testing strips — that is, 
in strips that have been exposed in steps in a testing 
machine. Though we know as a matter of fact that each 
step is absolutely uniform in density, yet, to the eye, each 
appears to be of graduated density, being distinctly lighter 
near the next darker strip, and darker near the next lighter 
one. The effect is. in some cases, so marked that it is diffi- 
cult to realise that it is only an illusion. The cause is some- 
what obscure, and need not worry us, but the kindred effect 
described by Mr. Lockett cannot well be mistaken for the 
true Mackie line, as the latter has usually a sharply defined 
outline, and is not graduated. Moreover, it is nearly 
always accompanied by the familiar " streamer " effects, 
which are most definitely not optical illusions at all. 



THE RECOVERY OF SILVER RESIDUES. 

Many photographers who have attempted to recover the 
silver from used fixing baths by the old expedient of adding 
liver of sulphur to precipitate the metal as sulphide, have 
been disappointed at the apparently small yield, and a 
little recent experience of our own seems to suggest that in 
many cases only a portion of the silver is recovered if the 
usual methods are adopted. Having some hypo solutions 
especially rich in silver, in fact, almost saturated with it, 
as the result of some experimental work, recovery seemed 
worth while, and the usual course was adopted of adding- 
liver of sulphur and occasionally testing with a few drops 
of .liver solution to see if precipitation was complete. 
Apparently it was complete, the test having no appreciable 
effect, but a few days after, when preparing to deal with 
the result, we retested, this time with a solution of pure 
sodium sulphide. The result of this was an immediate and 
very heavy precipitate of fresh black sulphide, which showed 
that the process of recovery was by no means ended. The 
final result was a big increase in the quantity of sulphide, 
but if we had proceeded to collect the sludge at the time 
when the liver test seemed to show that the silver was all 
down, a very big proportion of the metal would have been 
thrown away. This experience is not altogether new, for 
years ago, when experimenting on the collection of residues, 
we found some little difficulty in determining when the 
action was complete. The pure soda sulphide was, how- 
ever, not then the common commercial chemical that it is 
now. Sulphide toning had not been thought of, so no 
demand existed for the pure product. We were, therefore, 
not able to confirm our suspicions in the same way, nor to 
introduce a better process. It was often stated that an 
excess of liver of sulphur would redissolve some of the 
sulphide, but no one seems to have arrived at what would 
seem the logical conclusion, that in that case precipitation 
would very likely never be complete, while the exact 
moment of complete precipitation, if such existed, would 
be rather difficult to hit. 

The truth seems to be that silver sulphide is by no means 
such an insoluble compound as it is generally assumed to be, 
while in some of its modifications it is pretty readily solubl«. 
It can exist 'in a colleidal state, in which it may be said to 
be s«luble in plain water. To some extent it seems to be ■ 



March 1. 1913.1 



THE BRITISH JOURNAL Of PHOTOGRAPHY. 



99 



^InWI? ill hvpo, or in soin« of the products into which hypo 

What we call liver of sulphur is an ex- 

\- and impure mixture of various sulphides, 

!, for all we know, may produce a 

_ iides of silver, sum^ of which may 

• much more soluble than others. Aa a rule, silver 

iili.'il.If Aiifii in solution is brown in colour, but this cannot 

1 in the muddy mixture of a hypo bath with 

, ^ ..(...ur. A used fixing Uith quite free from 

jjer will turn brown aa the result of silver sulphide 

'ition, and it will be a long time before the 

appears at all. If we boil a clean hy]x) 

■n in which silver bromide has been dissolved 

II u«>t tli» sairie effect more quickly, while if we boil 

' I u by a 

mixture 

It it IS II to say, 

- ever)- cli i goodly 

liver iailinf; to romf down to .-.well the 

._ and the amount "i the refiners cheque. 

by the u^e of the pure su<la sulphide crystals 

' '"■ '"vioved, and there does not seem 

why the pure salt should not 

I lit- i'i>- »,ir if-i.i.' - -■ tire soda sulphide 

isrcial [lotassium •• " liver ") were 

•• : po«si(>' -.-lit may 

■. for til. 'aiiifis i' 

• is 
i.ler 
At 
the 
iiy. 
I uni 
>r. ' 

lied 

.ine. We have i' ntly 

■"ooee betwrr- ■ .j^iw 

lies. B< lent 

iM.iiKiii.Tory as compared wiiii tiie pure suUa com- 



A SPECIAL PROBLEM IN DEPTH. 

(••^'ard to dfiptfa tliere continually %fir* que«tion», 
i«w of which concern M>n>«what unusual coiKiition*. 
Dg a kncjwledg« of .points not always understood. 
-OU8 pwblishnl foniruhe and tabic* enable ono to 

jl-to .1.. ,i....ii, ,,,„., y^ ^ ffiveii lens with a cert*in 
reverts prohlesn crops up, and 

l»v«" u» mm lilt wii.it sto{> B ' • ' • ' i.>e a 

doftth. The fRm* table* ma'. lerv, 

Sf ■ ■ • ■ 



I at all 
tindor 



I in any tahle-i. 






i»t careluliy, 

.' calculate out 

.III' I most probably to 

CAM. Suppose a 

' ' 'ograpbed 

' we then 

t ut ^'reat depth and 

Rsrp a.* <(iioh ca«ie:» 

A-itlh at timoH. 

It i- =ir,ni<»- 



approximate eize required tlran to att«inipt to arrive at it 
by triaJ and error. To aN-oid having tb use* stop smallen- 
than is nece^iary the first thing to-be done is to ast'eirbaiu 
the right distance on which to focus. Threei distances 
are involved : that from tJie lens to the nearest part of 
the object-, that fronithe lens to tlie most distant part, 
and then the dietance of the plane upon which we shouki 
iocus sharply. The third distance is, of course, lan inter- 
mediate one, but the plane on -which we sliould focus is 
by no means halfway between tlie nearest- and farthest 
parts of the cibjet^, th-ougli it is |Of\yai a^eunied to be. It 
is really .cnly -a relatively short distance beyond the nea-rest 
■part of the object. It is quite easily found, for, in mathq- 
matir'nl Innguage, the ainddle distance is the harmonic 
nu • <m the other two, which means that it is equal 

to ' "ir product divided by their sum. Suppose, for 

example, the near point is 3 ft. from the lens and the far 
{>oint 5 ft. Then the distance on which we should focus 
ia the -harmonic mean between 3 and 5, which equals 

1-— : -: — = 8}, Bo thftt we should focus on a distance 

of 8 ft. 9 ins., or only 9 ins. beyond the nearest point. 
This ^xtTH distanre mu-it -he noted, as it comes in when 
ca' '^1. 

.re, which can be expressed 
eii le iorm oi the //number or by the diameter. 

Tip iiig are the data that w« require: — 

/=The focal I«ngth, w^ich we may as(<>umeto he 8 ins. 

/ Ti... .listamee of the phtne in sliarp focus beyond the 
ne lit of the object. This we have already found 

to oe ;» Ills. 

K^Tbe distance fitom lens to nearest part of object, 
which we have (aken at 3 ft. or 36 ins. 

,/=Th*» d>?^»n<-«> frniii tli« plan<> in sharp focw, not to 
tl . * us of the tens, that 

4> ■ nice of it. We liave 

already to\. <^m the lens to be 3. ft. 9 ins., 

therefore ti. mted is 3 ft. 9 ins. less 8 ins., 

which equals 3 ft. 1 in. or 37 ins. <* 

y — II- we nruiH. decide on the amount of confusion to 
^>- in the inisife. Ft is very usual to taJce this ss 

I-iiHi Ml . but in practice this i» too much, certainly in & 
case like the present, where good focus is desired. It is 
therefore beet to allow only 1-200 or 1-250 in. 
take the former. 

Having these data the //number is equal to 



We will 



200 >* 



11./ 



3<? X 87 rtoor:«o 

- „ = .0025 ins. 

200 X H X 9 



nailer than any provided. A tempf-rary stop will have 
b* '•>■■'■■ •••'i ■• • "i- Tujckei to calculate out the 



which in mrr awunied caite eqtfals 

200 X 64 X 9,- fioar 

If we prtitT to get the diameter of the stop, which is 
• lly more convenient, we use the ffoHowing 

ila : — 

I'OO f b 
wha(""\^^niay "call one-eleventh of an inch. 

Such a »U»p will have to be made, a<« ft is cert*ain <.he 
len« will not he pTV)vided with it, ibut very , good temporary 
«t be easily made in opaque black paper. Card 

i> k ; the best way to proceed is to cut a ring in 

car.] th.il will fTt the lens, then paste .black .paper over it 
and in that cut cut the stop apettiire. Such a stop pan 
be fitted without murh difTiciilty to any lene. 



Rkoistration or Bcsisess Namss. — Samiirl George O»boncl. nf 
Bank Chsmben. HiKh Holbom. was fined £20 ni Bow Street Polii*- 
Court last week for fsiliiiK to furnish the psi-tioulars required under 
the Reffistrstion of Burine»< N sines Act. 1916. 



100 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[March 1, 1918. 



OLD PHOTOGRAPHIC BOOKS OF NOTE. 



Photogbapht, as an art or craft, has experienced various for- 
tun«s in ditferent countries in the matter of its literature, 
using this latter word to denote not only the photographic 
lext-books, but also periodical publications dealing witli photo- 
graphy. In this country, with one or two notable exceptions, 
the books and treatises on photography have Iieen essentially 
of a "scrappy" and superficial iind^— more so as years have 
gone by and photography, from being the craft of the skilled, 
has become the pastime of the million. Broadly, it is true 
that the photographic public in this country at any time witlun 
the jKust fifty years has been averse from si)e.nding more than 
five ;>lullings or so on a text^book of photography as a whole 
or on one branch of -it; and within more recent years if it 
was desired to issue a photographic text-book in such an 
edition that its publication realised a fair profit to the pub- 
lisher, a- shilling, or half-a-crown at the outside, may be said 
to have been tlie price which it was naceesai-y to put upon it. 
It is clear, then, that in these circumstances the text-books 
ill this country could be no better than vei-y summary treat- 
nientfl of the subject as a whole, or even of parts of it. On 
tlie other hand, no country has been better served in tlie way 
of its periodical publications. With the sole exception, per- 
hajw, Df the " Bulletin " of the French Photographic Society, 
there are no photographic journals which can point to a past 
record of publishing the most valuable and important con- 
tributions to the advancement of photography as can " The 
Photographic Journal," the organ of the Royal Photogi-aphic 
Society, "The Photographic News" (up to some fifteen years 
ago), and, we hope we may be allowed to say it, " The British 
.Journal of Photography." The United States, wliich is little 
better than ourselves in the matter of text-books, has been 
always fai- below us in the chai'aot.er and importance of its 
photographic periodicals. And as regards the two other Con- 
tinental' countries, Germany and Austi-ia, to which the re- 
inaimleir of the photographic literature chiefly belongs, it may 
1)e said that while " Photographische Korrespondenz " has 
had its good series of years, no other German or Austrian 
photographic journal is able to take a place beside the three 
British periodicals whidi we have just na7ned. On the other 
liand, those who have written in the German language have 
for years past been second to none in the thoi'oughness and 
coonprchensiveness with which they have embodied photo- 
graphic knowledge in a series of ' most comprehensive text- 
books. It is scaix:ely necessary to refer readers of German to 
the volumes of Dr. Eder's " Handbuch der Photographie," and 
the almost equally compendious volumes of Pizzighelli. In 
France a similar cncj'clopjedic -work, that of Fabre, stands to 
the credit of our friends across the Channel and encourages 
the hope that the writing and publishing of such a series of 
volumes are not tasks only within the competence of a Teuton, 
but may one day be accomplished in a way worthy of its 
subject by the Anglo-Saxon community. 

So much by way of introducing what is the main purpose 
of these notes, namely, to signalise the few volumes, some old 
and some comparatively recent, which may appropiiately come 
witlun the scope of the collector of photographic books. When 
I say collector, I use the term in a wide senSe, namely, to 
mean the man who buys such books for his own pleasure as 
well as he who gives a shilling or two for the volume on tlie 
second-hand bookstall with a view to making a profitable sale 
o! it lateir on. As regards those of the latter category, it is 
neoesrsary to remember that the market for old photographic 
books is a small and peculiar one. It does not compare in the 
least with that for, say, first editions of Dickens or Thackeray, 
for the reason that private collectors of the past literature of 



our craft are practically non-existent. SaJes of such booki 
are made not to persons or institutioiis who value them foi 
their rarity, but, in the main, to concerns which requir( 
them for incorporation in a technical and utilitarian library 
Thus the Patent Office Library is a regular buyer of books oi 
photography, which forms an important section of its collec 
tion in Southampton Buildings, and is duly catalogued in thi 
" Subject List of Works on Photo-Mechanical Printing an< 
Photcigraphy " publislied in 1914, price 6d. But perhaps thi 
greater number of saJes are made to tlie institutions in thi 
United States, such as the Smithsonian Institution, th< 
Franklin Institute, and technical laboratories such as those o 
the Eastman Kodak Company and the General Electric Com 
pany. It needs hai-dly to be pointed out that European worki 
on photography are much rarer in America tlLan they are here 
and thus for this reason alone tlie old European book com 
mands a better price with an American institution than wit! 
one here. 

As regards the books to which these remarks apply, on( 
seldom met with is Hunt's "Researches on Light," the firs 
edition of which appeared in 1844, and the second editioi 
in 1854. A fair value of either' edition now is from £1 U 
£1 lOs. The volume, it should be noted, is not very properlj 
named, inasmuch as its subject is not light itself, but th( 
chemical action of light; the volume embodies the many ex 
periments and minor researches carried out in these early dayi 
by Robert Hunt, and contains a mass of observations, mani 
of wihich have now been forgotten. It is to be distinguishcc 
from the "Manual of Photography," by the same authoi- 
which ran through a series of editions from about 1851 t< 
1857, and is a book which can frequently be met with in second 
hand shops. Its value is small, about a shilling or two. 

Of a greater order of rarity is a small volume of 58 pagei 
in paper covers by Louis Ducos du Hauron, viz., "Lei 
Oouleurs en Photogi-aphie : Solution du Probleme" (Paris 
1869). In this book, and in a second edition issued in 1878 
Du Hauron who was an inventor far in advance of his time 
outlines not only tho various mertJiods of making colour print: 
on, paper by the subfcractive processes, but furthea- sets oui 
with considerable precision the various alternative systems o: 
screen-plate photography, which, thirty years later, were fiis: 
realised by his countrymen, MM. Lumifere. A reasonable pric< 
for either of tliese books is fi-om £1 to £2. 

In colour photography, again, a volume which is rare but is 
of impoi-tance in the development of processes of colour photo 
graphy, is " A New Principle in Heliochromy." by F. E. Ives 
published in Pliiladelphia in 1889. 

The Daguerreotype process is the subject of the first text 
book ever written in connection with photography, namely 
that by Daguei-re himself, entitled '"Historique et Descriptior 
du Procfed^ du Daguerreotype" (Paris, 1839). The transla 
tion, by J. S. Memes, appeared the same year in London undei 
filie title " History and Practice of Photogenic Drawings and 
the Principles of tlie Daguerreotj-pe." Both books are veiy 
rare, as is also another, apparently also a translation frora 
the original French, " A Practical Description of the Daguerreo 
type," a translation by J. P. Simon. This also was publishec 
in 1839. 

The original " Historique " has a value of about £5. A re 
edition, also of 1839, with supplementary notes by Leveloui 
and Susse Frferes, is priced now at about £3 ; and the Englisl 
translations have about the same value. 

Coming now to more recent works, a volume which can stil 
be picked up at booksellers' in Charing Cross Road for s 
shilling or so is one of the best written and oomprehensivt 



March 1. 191&J 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



101 



trxt-bock* ever published in photngraphy, although dealing 
part with pnicesses which have now become obso- 
■ A Pr;urtical Guide ti> Photiigraphic and Photo- 
j! I'rinting," bjr W. K. Burtun, published by Messrs. 
..» 1887. 
In the field r.f tensitumetry and meaaiirement of plate 
jii"--^l>. a rare little borik w>hich is now often asked for is 
56 . f the Photo- Miniature" entitled "The Hurler and 
•■'.1 System," written by the late V.C. Driffield, and pub- 
Messrs. Tennant and Ward in 1903, originally at 6d. 
I iiK :ii[le DK.>nogTaph on a subject which has since come so 
murh to the front is no™» fairly pricetl at, say. 5s. 

On th. ' i- a comp I • it volume which 

ha« ii.iw . mt and. ; ug dead, is not 

likely to U* jci»u«:U. is ' Tom WiniwiuoiKi. The First Photo- 



grapher." by R. B. Litchfield. This is the only book whirli 
contains a correct and critical account of the early ex|K'ri- 
ments of Wedgwtwd in photography at the latter end of th.> 
18th <?entury, and a description of other work for which 
priority has l)een claimtd in relation to Wedgwood's. 

Another verj valuable bm.k to the photographic historian 
whicA i, now difficult to get is the catalogue of the Exhibition 
at the Crystal Palace held by the R»>ynl Photographic Stx-iety 
in 1898. This catalogue contains a lengthy review of photo- 
graphic lenses from the very earL«>«t perit^l to the date of 
the Exhibition, together with notes on the photographic 
technique at the time of th? Exhibition. Probably no other 
volume supplies the same accurate review of tlie state .f 
photography at this time. 

BlBLIOl'HII.C. 



AXIAL ABERRATIONS OF LENSES. 



[We are indebtad to the Boraan of Stana»nl« of tb« Unit«d SUtM Deputmmt of Commeroe for the following paper, which deal* 

• h the chief axial aberratiooa of Ici scribes io detail the practical method worked oat by the Bureau, based upon that of 

I'tm^nn f'-r th* mea^uremanlaod plo' >" aberrations. In reproducing the text of the paper, exigeocie* of space have oompeUed 

on, namely, that dealtns matbomatioally with the aouroas oC«error. A brief abstimct of this aeotion is inserted 

11 iU apptopnate place.— ED6. " B J."] 

'lefimtion in liie osotre of the Md 'rf n lefM ^yitrm i< c<-n«raJly 



Tf re«|ui 

.ii;e ..f • 

ij tru» 



>i*d to be good, bat its reUt 
me varin greatly In a telr- 
■• of the fieM ia u»»d, the rrrom in. 
wliile th<M« which affm't only thr . 
In a jm*]*.!!.!!! lri\» itie •.iiti.- 
'■I* m-^rt* ol th«* field i* ui«»ii !' 
tnil r<irTr<tH>iiii »r' 

■ ■*'• ll>» C1M( III til.- 

tance from the projected picture doM not 
111 the image, 
-oeea a Urge Aeld i* very deetrabli 

• ri* .ltt4*fltjiin riiii«t \ 



t lens 
y thi- 
>rrBc- 
in be 
I w ir 
■biec- 



.1 



pr. 

in 



■( 



■ tirrr U* ' 
lid in 

*n»,-r.,i •[.Ml I. -11*1-.. i.i'.M. Ilfled 

{Utrcd which i* Isrse rrlative Ui trl< 
lenere for ordinary ph' ' 
"d to be conrecied very a. 
. inoogb eoloor ta of eet-rit 
"«n. or p l rtc e which are smki 
ni, may be iwed. 
luea the oentml definition 
the «t4d. 
:'nnitinn tl 



really a 

... ,i..r....i„i„ nj 

Here 

<- JIM, i.iiff edge 

well oorrK^ed 

.tue Ui ihr 

teru than 

'i.oit in 



•I, 

•-t.l! 



I'' ^ a Said 
• ,t snail 

' t M field 
-Ml (nail 
•-, since a 

•biirt rania 



nf (trveter iin|>ortance 
"n Uie eyaa 
.the 



ti'ui on the rxjtivmuM wiUhhiI diraeting 



.■t>«r- "f the ft^H -.vilt 



ri i« very imimriant. .iiiH thr 
.TTn-raliy 
tioos 
■litioll* 
com 
.). the 
if not better. 



•i deiinitina mnat be ai le«M aa go»<i as ttm • 

P«rpo«« of lBw««ti<*tI«a. 

- fnllfMina investigation was uii'l'-'^ >ki-ii to determine the 
lens system whii h leAirition of the 



!re »»f lb» fi»IH 



■*rt Hie ranoua 
■■ mrrectiona for 
lie parpoeee for 



which they misht be used. The lenses investigated were in the 
following |.i .5<«es :— Photographic lenses of relatively lang.- 

niKTtiir ■ : lenees for stereapticon and motion pict\in- 

>- I" lenses of short focal length and large aperture and 

t. . -!■ MIS. 

Crror« Affeciing an Optical Image. 

Il •«<:ii< .i.li ij.ili!. I !■ ti;.,> and deacribe the errors found in 
optical •. S:n« t>rl'.ri' i.n« .iiling to di«cufs the iiiKhod used in 
detani' ti. Kanh one of these errors i* called an aberra 

tion, ti , »-\.Mi Mih' Dial aberratiorw, namely : — (ll .Vxial 

rhnimaUr, (3) *pherical nberration. (4) zoiiul 

variation of .^jth (sine condition), (5) curvature 

oi Aeld. (6) aatigmatuun, and (7) distortion). / 

1 Axial CHKoxATir .XncRRATiON. — When a ray of white light 
(Fig. 1) peases through the lens LL at V- » prism action is exerted 
»,iii th,. n»v »i>d the whit** U'-:Kt i* hrnlo-n no int»» it** romponeut 




FIf. 1.— DtafTam lljnsiralini asial otaromatio atsnsUoa. 

element*. Ttie red component, or the ray of longer wave lengtli. 
is bniught to a fiKU* at a point /-*,, faKher from the rear lens sur- 
face than the violK i-omponent or the ray of shorter wave lengtli. 
which is fncuaaed at /',. The intervening wave lengths are focusseii 
b«'l«eeii the point* /', and I',. This error i> known as axial chni- 
matic aberration. The amount of diromatic aberration, or the dis- 
tance P, /',. is denendeiit upon the focal length of the lens mid 
the dispersion of the glnas By "ombiiung two lenses of proper 
focal lengthe and glssses of suitable refractive indices and dis- 
persions, the axial chmmatic aberration can be minimised — that ic. 
two ooionrs. such as red and blue — may be brouglit to a focus at 
the same point and the other rolours be made to focus ver>' clo«e 
to this point. 



102 



THE BRITDSH JOURNAL OF PHOTOGRAPHY. 



[March 1, 1918. 



2. Obuqub Chbomatic Aberration. — Even wben «U ibe colours 
iie foCQsaed at the game point, the equivalent focal lengths of the 
\;;iioug colours may not be the same, and each colour may give a 
different sized image, causing Uie familiar coloured fringes to large 
object*. A particular example of this is found in tlie lenses used 
II three-colour photoengraving, where, if the focal length for tvhe 
led is slightly longer than tliat for the blue, there will be a red 
fringe to the image. This error is known as oblique chromatic 
aberi-ation. 

3. Si'KEBiCAi, .Aberration. — Let LL, (Fig. 2) be a convex lens, 
with the a.xis P,M, and l'„ I\, P„ *nd T\ be four i)>arallpl rays 




^^iS' 2.— DiagrjLin illustrating Bpherical aberration and zonal variation of 
K. F. L., and graphic method of representing the same. 

strfking the lens ajt points $,, Q^, Q,, and Q, at heights h,. h,, h„ 
and h, from the axis. The rays, after ibeing refracted by the lens, 
will cut the axis at some point. Let the ray from P, travelling 
infinitely near the axis cut the latter after refraction' at P,' ; then 
P,' will be the focus for a paraxial ray (ray very near the axis). 
The ray P^, striking the lens at a heig-M A, from the axis will, 
after refraction, be brought to a focus at P'^. The ray fi-om P,, 
striking the lens at the extreme edge at a height h, fix>m the axis, 
will be brought to a focus at P^\ nearest to the lens. If V 
represent the paraxial focal length, then P,'/\' =4'' '' known 
as the aotial spherical aberration. 

If we draw Q^Ii^, QJt^, and QtSt parallel to the axis, and erect 
the perpendiculars aJt P^', P,', and P,',- and draw a curve tlirough 
tie intersections P,', It.^, R,, and It,, we obtain a curve ^vhich 
represents the spherical alberration along the axis for any zone of 
the lens at a distance h from the axis. 

In a negative lens (Fig. 3) the ray through the edge zone, if 
prolonged backward, would cut the axis at a point P^' nearer the 




Fig. 3.— Diagram illostrating spherical aberration in a negative lens. 

lena than the point P,', which is the focus for paraxial rays. But 
here the spherical aberration P,'P,' = AV is opposite in sign 
from that of the positive lens. The size of AV is dependent 
on the shape of the lens for a given focal length and kind of glass. 
By combining a positive and a negative lens of the jwoper shapes 
and of glasses and focal lengths previously determined by other 
M.nditions (axial thromatic, Petzval, and oblique chiWatic in 
photographic lenses, but only axial chromatic in telescope objec- 
tives), the spherical aberration of the negative lens may be made 
to counteract tliat of the positive lens, and thus be eliminated. 



In tlie absence of spherical aberration the curve P.'if, will coin- 
cide with the line P,'Y. 

Variation of Spherical Aberration with Colour. — The spherical 
aberration curves for all colours do not coincide, nor do they run 
parallel to each other, since the axial chromatic aberration for 
different zones is different. Hence, it cun'ves are drawn for light 
of different wave lengths, each curve would represent the axial 
spherical aberration for that wave length, the variation in the 
s.hape of the cui-ves representing the variation of the axial spheri- 
cal aberration witih the colour. The abscissa of each curve for any 
definite ordinate is the spherical abei'ration of the zone represented 
by that ordinate for tlie given colour. The difference between two 
such abstiissse is 'the axial chromatic aberration of the zone for the 
two colours. Thus, tlie curves show spherical and chromatic aber- 
rations, and the variation of the spherical with the colour. 

E. D. TlLLYER. 

H. I. Shultz. 
(To he continued. J 



1914 


772 


1915 


812 


1916 


729 


1917 


888 



PROFESSIONAL PHOTOGRAPHERS' ASSOCIATION. 
The Council's Report fob 1917. 
The following is the report of the Professional Photographers' Asso- 
ciation, to he presented at the annual meeting on Friday next, 
.March 8, when Mr. A. H. Llewellyn Chapman, of .Swansea, will be 
elected president : — 

Daring the year 101 new members have joined the Association. It 
is not possible to state with accuracy the actual number of members, 
as some who have not responded to applications for tlieir subscrip- 
tions may have joined up and may or may not return to photographic 
work and memberehip. There is, however, no reason to suppose 
there is any decrease, as the subscriptions collected, 888, is the 
highest number since the institution of the association. In this 
respect it has been the record year. 

The following table shows the subscriptions collected for the past 

five years ; — 

1913 ... 777 ... Congress. 
Congress. 
No Congi-ess. 
No Congress. 
No Congress. 

The business of the Council has necessitated a monthly meeting 
throughout the year; so, for the fii-st time in the Association's 
history, this year there has been no suspension of the meetings during 
the autiunn months. 

The P.P.A. Circular has been published regularly quarterly, and 
the considerable number of expressions of appreciation received from 
(members has convinced the Council that the labour and cost of its 
production have been justified, and will encourage them to further 
developments and improvements. 

Through the kindness and courtesy of the Kodak Company and tlie 
Editor of the " Professional Photographer," which the Council 
gratefully acknowledge, a statement of the constitution and aims of 
the Association was made in the coluirins of that publication, and by 
those means reached evei-y recognised professional photographer in 
the kingdom. A form of application for membership was enclosed 
with each copy, and the direct result was the accession of fifty-one 
members. 

The coming into force of the "Registration of Business Names 
Act " v/as duly notified to our members, ajid full particulars of its 
provisions were set forth in the February nuimber of the P.P.A. 
Circular. A large number of inquiries resulted, several of them 
involving intricate points, which had to be considered with delibera- 
tion before the application of the Act as regarded them could be 
determined. In spite of the clear instructions given in the Circular, 
a considei-able proportion of the members liable to registration, etc., 
.seem to have failed to notice or take regard of their obligations. In 
certainly more than twenty cases letters have been received from 
members on ordinary mattei-s, written on letter paper, the heading of 
which clearly did not comply with the law. In all these cases the 
member has been warned of his omission. The frequency of these 
cases necessitated a further notice to members generally, which was 
printed in the November number of the " Circular." 

In a, few cases the printed heading of letters received included a 
representation of the Ro\-al anns or wofds implying that the person 



h 1. 1918. 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



102 



or firm enjoyed Royal patrona(;e. When it waa dear that the 
member was not entitled to aoch use, and that it waa an infringe- 
Dt of the Patent Act or Trade Mark* Act, a warning has been 



pven. 

In August tho attentiaii of the Coonoil waa directed to a circular 
letter that was bei- val of, the Director of 

the National Portr , ; and Army oflRceri an J 

oth-ri in high official pusitioua, ins ;tiu^ the recipient to attend at 
a . , r-..!.!! pbotografher'd studio for a free sitting, in order that his 
portrait ahoold be iacladed in a collection of portraits to include 
thoee of "all peiaons, naval, military, or civilian, holding important 
an<i responsible poaitions, and other» who have rendered service to 
their oooBtry in this great histoiical epoch by their valeur or by the 
promotion of the welfare of the Empire." Aa (he oflen by recipient* 
of th« circnlar to contribute portraits of themaelvea already in 
«ziat«(ie« were replied to by the firm uf pbotngraphers referred to, 
on their own bnaincH letter paper, stating that only their photo- 
grapha woold be included in the collection, a letter waa adJremed 
by the bon. aecretar>- t« the UirecUu- National Portrait Galleri-. 
asking if this waa the fact. No reply ttjiMtd an acknowledgment 
having been received for some weeks, hf diNCtaon of the Council a 
latter for pab)icatioa waa sent to and mppttred in certain news- 
{wpets, painting ont that the metlud proposed for obtaining the 
liiiilisila iiwiiilj. that tbey were all to be prodoced by one London 
photographer — most neceasarily be ineffectiTe. 

A series of advert ies ment s in the Loodon "Evening News," 
eflerii^ iia readars ooloorgraph enlargsnenia for 7s. 6d., from 
a piwtognkph of anyone serving in the Forces, waa brooght 
to the Cooncil's notice. An acooant of wkat happened in tiie case 
of an order for ooe of these eulargeoMrte was gtveo by the hon. 
secretary. 

A soneiiiao from Mr. Lang Sims that a fund be raised for the 
baneSt of piMtognphsn who have lAvu iNvrt in the war and reqoirv 
aseiataoce on their retain to a-- was eoMidarad by tfie 

Couaoil. The difficoltiea were ( . :. ,;uiaed, bat a oooniiltce 
waa appointed tu '.n(|uire into the nmtler. Vp to the finaent no 
defiason has been srrived at. 

The andioatiena for adrioa or Msistanee on b n i tn sm msttsw have 
a« nnmetooa and vaKsd in snhiset as oeaal. In ea*arai 
t^ .\jaociat«on's opportanity of obtaining a seMlsmenl by 
lion hea been deattoyed by «ur nsnber, after an atrimonioas 
having thraateoed his opponent with placing the 
imrrr in the hands of thr " la enek cases, usually, the 

4Mly lasrift is to fmploy a r 

The sale of old negatiTea u> [M-ixins '«Im> are mors anxioos to 
obtain the glam than to pay for it baa givea as a gr t a t amount 
of uouUc. and hm necaasilated the atrrkea of our soboHor. In 
most cassa he has obtained a sotUifBaat. Payment baa bean 
nhlsinsd from a glass oompaay in ei^ caass with and without the 
e u — W B OiSBt of pinrewMny Other caaa are still in band. 

Tlifaa eaasa of the refnml to pay for oU B a g stirsa by tiieir por- 
ihessri on aocDunt of liM gUaa beinf VDclaaaabla kava ocenrrsd. 
In ooe oaae an adjuMment was made hy ooasent. In the second 
there wM a rootim accooot, and the legal poattMn iiiaim w s il oa- 
dended. The third, mhiet involvrs a very cooaidanbie snoiiiit, 
is being dealt with by our suiiritom. 

Many eoBplainla of (oode ordm.) not being delivered after con- 

of time have rearlinl iw. The difBculty in dsaUng 

aoek «aa« arisaa from -the uiy issi b ility of detannining the 

miming of " raMonable tune " ondar esialtng circumatancea. 

Two daima by rVenU againal m i m b— for delivery of negative* 

have been saoresafally misted. 

Several cases of minor infringements ct copyright have rmnlted 
in obtaining reproduction frw« or rioall dunagea for manlien. In 



£3S were ofataiiw4l .V 
"Daily Mlrmr" pubhahin.: 
i t i e sat sent them by a pelt 
iit pfoved that the ptw 
pfaotografifaa, ear iiR«nl" 
the aender £12 12*. fw^-. >• .v ... 
aamabsr the same amount. 

In another oaw of al lege d in' 
^aioat had, fortonatdy for hin. 
oar mentber dated twelve years j 



i{ raae wne that uf the 

: phologrspla of naval 

the Nary. On investigation 

•■■ •>><• paper were oopiea of 

Iiaper had already paid 

•-.<-.. met ua by paying our 

— --* the pemon complaine<) 

iie onrreeporidrtM-e with 

..1!.■^:^g coodnaively that the 



photo^9|lhB were taken to order and 'were not our member's 
oopyrigfat. 

A complaint of one of our members against another that the latter 
had endeavoured to induce the former's nxuwger to transfer his 
services, was held by our solicitor not to be a breach of the Defencf 
of the Realm .\ct, as the attempt did not succeed. If it had soc- 
ceeded it wouid have rendered the offender liable to a, heavy penalty. 

Two important casce of goods being invoiced at higher prices 
than the contract pv'.ce have reaolted in the contract price beini: 
maintained. 

The Fine Art and General Insurance Company have given notice 
to termiaate the arrangement up to the present existing with the 
Association. The Council are still considering what new arrange- 
ment can be made in the interests of our members. The new arrange 
menia will not ^ect members already insured against fire and some 
other insurance. , 

The thanks of the Association are due to the Editors of the 
" British Journal of Pbotogra|ifay " and the " Profeasional Photo- 
grapher " for publishing repotts, infonnataon and helpful reference 
to the Association's woHc. 

By order of tiie Council, 

Alexander Mackib, Hon. Secretary. 

January 12, 1918. 



Jisslstatits' RoteSe 



t/otu fry auUtants tuitabh for this eoiumn teiU bt fruidertd 
and paid for on tkt firtt of the month following pubiicaliit. 



Eaael and Bromide Paper Catch. 

methods in use for fixing bromide paper 



A Uaeful 

Or t!i.- \.in."n • 

to the i-iLl.ir.::ng eaM>l, and tiieir merits, I have had but lilUe 
eaperi' :.' •', i"it the following device has beerf found to work satic 
hctonly for a number of yean in the production of all the various 
sixes of prints, (rum postcard to 20 by 16 and over. Aa regards 
spaed and airoplidty, I do not think it can be much improved upon. 
The eassi, woriring on wheels, is fitted with a aquare of fine ground 
glaw ia the ccutr6, size 12 by 10 flush to tj^ surface of the front 




of buonl, and proving a niafal means of fine focussing, viewiug 
from the back of eaael as with a camera, The paper-olippini; 
rods are. working frr>m the oomers, made to fix aiiy sixe of pa{>«<° 
to any part of the eaeel board within its working; area, which in 



104 



THE BRITISH JOURNAL OF PHOTOGRAPH V. 



[March 1, 1918. 



isily uii'l f)ii!ckly di.iie witlioiit piei'dtig the paper. Also the paper 

, Very tjuickly removed when expt)sed. 

The sketches will he)p to expbiii. The spriiiu brackets to hold 
tiie sliding rods can be easily made by a smith. They are hai\lened 
to give a firm .spring. Mine are homemade t'ix)m pieces of gheet- 
iron, being first pKed into sliape and then haixlened. They are 
- inply fixed near the corners of the easel by means of a stout screw 




eye so as to allow of a side to side mo\ement of the whole fituji 
across tJie board ; the tubular socket is made just large enough to 
receive and hold the arteel rods firmly against the board when let 
go (my rods are fairly stout umbrella ribs), and loosely enough 
held to allow of the whole tength being slipped kickwards and 
forwards bx>m corner to centre, and rife verfa. Tliere will be some 
spare parts of tht rod.i generally projecting beyond tlie corner of 
easrt, but not of sufficient length to be nvuch in the way when a 
good size board is used. These witches will hold ))lates when 
required as well as paper. — M. B. 

Two Hint* on Vertical Copying. 

The first is to .<t-.ck a piece of paper, on whicih thei'e is some sharply 
printed type, under a smsll ipiece of glass (preferably plate-glass), 
so that the type shows through the glass. An old c.d.v. cutting 
shivpe is quite good for the purjjose. This lis just di^opped on the 
copy for easy fcx-ussing, and will lie in good contaot with it. 

The second idea is to make a sort of bo.x, a-! shorivn in the sketch. 
t ' supfjort a piece of mirror on top of the canie.-a, so as to enable 




one 'to examine the image by looking straight forward instead of 
cianing one's neck. In many cases where tho copy ds well lit H 
will be possible to arrange and to focus the image in the mirror. 
This may be a piece of ordinary silvered sheet or plate for this 
purpose, and the 'box is simply placed in the most convenient way 
on the camera, preferably so that the mirror faces away from 
the source of liiglit. — D. B. • 

Soft Bromide Emulaion on War Paper. 

When bromide emulsion shows a tendency to soften or melt, there 
are various methods of hardening, all of which are more or less 
.effective if the emulsion is on paper or card of prewar qualiity. 

Uealing with emulsion on paper of recent manufacture, however, 
does not seem to be such an easy matter, the film apparently not 
having as good a purchase on the new base. 

I have come across a large amount of bromide paper and card 
during the last si.\ months, the film of which, on contact with hot 
hypo-alum and sometimes in the case of sulphide, softened and left 
the base. All this bromide was of well-known makes and high- 
priced, so the fault was not due to cheap material, but rather to 
" war paper. " One maker who was questioned could give no infor- 
ri ition about the matter. 

Ihe U!<e of alum in sufficient Quantity to prevent softening caused 



the film to crack, split, and peel. Sulphite, acetic acid and alum- 
used as a separate hardening bath gave better results, but was not 
reliable, some batches of paper being affected by it differently from 
others. Formalin was no more successful, the waste in all cases 
being serious. 

Fixing prints in a hardeiiing-fixing bath, such as the hyixi, 
sulphite, acetic acid and alum formula, and then treating theA with 
alum (common or chrome), formalin, or saturated hypo solution, 
only seemed to make things worse, square inches of film sometimes- 
peeling off without being touched. 

The only reliable way I ever found to deal with prints on this 
kind of material, if they are wanted for toning, is that of using a 
" soft" fix;:ig bath composed of hyjio and a very small amount of 
I'otass. metabisulphite. By " soft " I mean not too stroiiig or 
cold — 20 per cent, solution at 65° or 70° being about right — a« the 
tendency to crack or blister must be counteracted. After fixing, 
the prints are washed for about five minutes, soaked in saturated 
chrome alum solution for about ten minutes, being well turned over 
and washed again for another ten, after which they are dried. 
When dry they can be toned with impunity. 

All alternative to drying is to allow the prints an hour in the- 
chrome aium, but the former is the safer way when the paper or 
card is extra faulty. 

This may seem more troublesome than leaving prints in a cold 
bath to tone overnight, but when large quantities have to be toned 
it is the more convenient method unless one has great accommodation- 
for hypo-alum. — Thermit. 



Patent ReiDs. 



Process patents — avp^ications and specifications — are treated in 
'Photo-Mechanical A'ov«." 

Applications Januaiy 21 to February 16 : — 
CiNEMATOGRA'.-HY. — No. 1,253. Cinematograph projection apparatus. 

E. E. Halford. 

Photometeks. — No. 1,473. Pliotometers. H. Nielsen. 

Camera Accessory. — No. 1.826. Optical divergence determiners- 
for cameras. A. Freeman. 

CiNEMATOonAPHY. — No. 1,812. Kinetographs. H. C. Schlicker. 

Shutter Fittikgs. — No. 1,631. Obturator rings. A, V. VVat^on. 

Films.— No. 2,319. Films. H. Degens, 

Cinematography. — No. 2,075. Stereoscopic cinematograph shut- 
ters. O.-Dimond. 

CiNEM.woGRAPHV. — No. 2,131. Haiid-tool for joining cinemato- 
graph films. E. W. Jchnston. 

Photographic Apparatus. — No. 2,026 and No. 2,109. Photographic 
appai-atus. G. de Ram. 

Printing. — No. 2.334. Photographic printing. C. J. F. Westman. 

Film. — No. 2,742. Apparatus for treating photographic film tape. 

F. B. Thompson, 

Cinematograph Cameras. — No. 2,720. Cinematograph cameras. 
R. Wellesley. 

COMPLETE SPECIFICATIONS ACCEPTED. 

Thett specifications are obtaviable, price 6d. each, post free, fron 

the Patent Office, US, Southamptoti Buildtngs, Chaiuxry Lant, 

London, W.C. 
fh* date in brackets is that of application in this country ; or 

abroad, in t'lie case of patents granted under the International 

Convention. 

Colour PnoTOGn.ArHY.— No, 110,089 (February 8, 1917) The- 
invention a^ of optiail means for taking and projecting still and 
animated oolouT photographs. In view of the technical details 
contained in the specification the major portion of the latter is 
printed in the "Colour Photography" supplement to this issue. 
Tlie five claims made for the invention aj-e : — 

1. Apparatu-s for itaking colour photographs, whether 
stationary or of the motion-picture kind, charablerised in that 
the rays of light of the component colours are separated at the 



M^rch 1. 19iai 



TitE liKJ'llSH JOURNAL OF PHOTUUK.U'HY. 



105 



ving ihe <|ii:ility of iwlcotiveJv 

uipODClit colours lu prepuiider- 

■ ' 1 

—i^-TTT pbotCftfaiplM, whether 

dwncterMed iu that tiie 

- vi. H^ rt the wir- 

ot aelectively 

►»■ ' ^ iiiiRjui-tit i.x'.ouiTt in prcpoodw- 

to oImd 1 or claim 2 further 



«urfac0 of a tran.<p 
tranamitting &nd :• ;--.-„ . 
alinf; degTe«- 

2. Apr ' •■- ■-■" 

stktionai 

rays of . 

faca of ■> 

tranmittrng .u.u ..n.-. .mi; u 

ating <i«gi«M. 

3. Ap|»mt(w according 
diaractMwd in that «ha tranMoitting and rpfleeting r«paciti«« 
of the redeetor aa to tb« rtwfM' live «ompoiient ooioan are pro- 
perly retatad (o th« degree <l--.n-o<> of senaiisrveneM or dcfth of 
cukmr of Ule opfMoitiy locatt-d iinag* aurfaoea. 

4. Apparatua aocording (<• riaim 1 or claim 2 further 
<^haraet<riMd io that the in< "inijriaea a plate uf 
giaaa. l aUwr cJear or ooloin ..t fare of which ia 
applied a aoperficial lay<er of a dteiitwc eual-tar or aoalogoua 
dye- 11111!. 

5. In or for um- in ihe Utkir^; at aJtibitiog of colour photo- 
grapha a dicbr .io dve r'-fl." ("r ftutxH^Uially a deaeribed. 
A. H. Walker, 188, F1. : C4. fur He« Itn 
Cnrpuration. 1201, R«<. a, I'.S A. 



Crade Ram^s and n?ark$. 



Ftao.' 



-\a2Se.50t By C. P ( ; - . 



UHSKWKU. 

in 1904 iru«> Ci. 



TRADE MABK8 RBHOV-" '■POM REGISTKB. 
In iJt* efieiml limifuagi of tht " . i Journal " tkt foUotntuj 

trad* mark* hae» btm " rmtottd (i.jr» tit* r»fu1*r thnmfh mm^if 
mmtt o/ rmttaal fen." Sack noa/Myauwl u </ court tht mttlud 
mdofiUd bjf a firm havituj no farlMfr i<etatitmfor Iht urn <^ a mark. 

HrT ;^x —No. 288,337 Rr ■•- - ' •- >^ H. hner and P L. 

I riton in 1904 (CUm . 
t\>: s — No. 259,336. RegutcrcU by U Ifffcner and P I. 
iiton in 1004. (ClaM 1 ) 



I 



Jf.l*A'.y PLACED O.V TBB REGIS TBB. 

Tk* (oUowtng mof kt kat* fcam fUtrtd tm Ikt rtguUtr : — 

Bn iM B I)c9ioM.— NoL 380^0. Phelograpli*. Fnrd RmJWI 
Bamrtte, 108. R-nfirld .Street, (ilMfpa. p^Mocrapfarr. 



rabrvary 16 to V 

P. T. y 
March 12 t 

8tU; 2. 
AprU 18 V> 

Sooiaty 

.\ore La: 

Rrad. Loodoa, W.12 



\n\G KUDrnoNaL 

irj^ notosraphic SocMy. Sac., 
rgh. 

ty. Sac, Walter 
6. 

iioMiaaiUi, VbUofnfhie 

Seca., R. T. CaU«a4«>, U>, 

T. W. Shirr*. 201. Goldhawk 



Wji«'« Hiaroai i.x Cou>t-B!— Prepaiwliaaa are prooecdiag qoiekly 
. .1... «-. ■^rand extii' • ■ ' '■— ^i? --,- - ' • ' ' 



(•e oftatti 
«- %ti(>'iii«rfi jiaa been orx-n'i 
tha proceed* wiU h« dwot- 



■trv 'ti I ni..rma: i->n, atmi 
•'« and purjMMM. 

f £1 la. 

-tmi^zine 

'■Itc Laa^ii ' 't<a 

hrtf nn-T the 

led 

iige 

.••r'n 

.■ ■ - ■ i to 

■.. ' thr 'i^'T-Stm Clob,- Itmtnl Building*, 

r.2. 



meetings or societies. 



MEETINGS OP SOCIETIES FOR NEXT WEEK. 

aAToaDAT, Mabcb 2. 

Blal»bridtre Pbotocnpbic andSeiantiHcSociety. " Tbc Principle* ol Composition." 

J. H. Oonthaw. 
Edinbarab Ptantogtmphit- ^ocialj. Kxbibition Lecture, "A SwJm Paeeant. ' 

O. W. Wight. 

MaKDAT, Maich 4. 

Booth London Pbotocnphle Socien. ■■ The Pfaotocrsphie Btadio and PremiK'i ' 

Urinkwater But. 
Dewsbar; PboMtraphie Society. » Amateur Pbotofrsphar." Prlio Blide*. 
C(ly o( London and Ciipplefcaia Phola(rapbio Soelety. "Uarden Plioio(ra(h}.' 

A. D. Kort. 
Bradford Pbotofraphic aoeietf. Torkahire Photographic Uhion 8Ude« an.l 

Meaban' Slide Nl(bt. 

Ti-iauT, Uuica S. 

BIna h ii h a m Pbotocrsphic Society. "Some Old Roman Tovdk of Provcncp. 

T. H. Waller, B.A., B.Bc. 
Haalay Photefraphic Society, T.M.Ca. Annual Mcetinii. 
SbeOleld Pboto(raptilc iVM-iaiT. "Prom JerKy to Bl. Mala un.! Mom St. Michel. 

Bnuaay." K. J. Cnbb. 
Kelcblry aad Diitrlct I'liuto^raphia Ataoclalion. •■ .\matcur Pbotoiiniphrr " Prize 

I.«atera tutdt*. 
Ilaekaey Pbolofiaptala Society. AffilUUoa Laalera Slide*. 



WiaaaiSAr, Mjiaca 6. 



A. U. UuiU. 



Hall Photatrapble SeelatT. 
Haddar*a>ld NaUtfallit aa<i 

Prtaw. 
l^mtttt Pbolaarapbte fVvlriy. 
t.tracpaai AaMU 

Mortbaralu 
Ha n i i aeii H t 

Jelwra." A.H.I. 
Rodleyaod D'ttrict I'; 



.tarn SI..'.. 



. MA«ca 7. 

ri." .Mr*. M. Chaplin. 

■".^..iii.o Society. Kxbibition ": ir,. 

. (nd r.f T!nlon Slide*. 

''Some Pre. War UoliJ*>» in 

.lapblc Society. "Flotsam and 

Soelety. "Albam Making." T. Ball. 



Commercial $£egal Intelllsence. 



.\ RsfSimio Orom haa been made on a creditor's petition againit 
Arthur Heat!. i her, lately carrying on buaineas at 22. 

■'it. Jamea Stt 



.NKW tO.MPAXIES. 

Ni;» STrDiii«, L.ii>. -Thia private company waa registered on 

February 15, with a capital of £1,000, in £1 shares, as photo- 

graplien, printer*, dealers in pictures and fancy goods, etc., and 

to catabliah at (iraiitham, Peterborough, or elaewhcre, bnuichen 



•liopa, staiios, fai-torite 
one share) arc : — (>. E. 
Grantham, chemist ; A. i ■■... 
fiad aooountaiit ; ti.aE. Hadley 
photographer. The first din-' 
Whit*, and G. E. H...1 
Joia|fy). Siliritor, T. .NOrtuii, 



■" etc. The subscriber^! (each with 
(ireen Hill, Barrowby Road. 
i'<>-fi»hira Road, Urantham, certi- 
■'<-. r irliament Street, NoUingham. 
U' ''. E. Whysall, A. 1 

(.' SO abann (solely < 

1. ,>t i •KT s Hill, Grantham. 



AnUAL PBtrrDORAPHT 

the Honac of • 
of the progr> 
Korcea and .\ : 
year 15,357 p 

PUOTOOKAPUS, i 

• Board of Tra<K' 
enijravers in Ix>n<l<>ii [iiji 
of the Royal Family. < 
should be addreaaed to 
lAindon for Canada '.' 



OM TBB Westcrn Front.— In hia report, in 

' M-ok, Major Baird, in giving an account 

>><.-en mode in the creation of the Air 

> d that in the montli of September laat 

' token in the air. 

^. — A ^laiiitoba oorreapondeut in the 

.uVlk !••!■ names of photographers or 

priced portraits of meinbcn 

- -- -1 -_ in regard to the foregoing 

the Office of the High Conun isaioner in 

Yulr.ria Sir..,.t s \V 1. 



106 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[Maich 1, 1918. 



Correspondence* 

•.* Correspondents should never toriU on both sides of the paper. No 
notice i$ taken of communications unless the names and addrestit 
of the writers are given. 

•.* We do not undertake responsibility for the opmiotis expressed by 
our eorre^yndents. 

METOL AND CHEMICAL POISONING. 
To the Editors. 

Gentlemen.— In answer to my query in the " Journal " of Xovejii- 
ber 9 last on the above ..subject, asking for a means by whicli I could 
cure mvself of metol poisoning, Mr. E. I.. Leaoh, photographer, 
of Clarendon Street. St. Giles. Oxford, kindly sent me some oint- 
ment, which absolutely healed my hands, the skin starting to grow 
after the fourth days' treatment, and in three weeks I was able 
to resuu.e mv dutie^. after six and a half months' pain. I notice 
in last week's " B.J. " that Mr. Leach has placed this on the market 
under the name of I'iah Ointment. 

H other photocraphera suffering as I did will give this ointment 
a trial thev will, like myself, be pleased in having had it brought 
to their notice.— Vours faithfully. P- H. Adams. 

Staff Photographer, " Illustrated Leicester Chronicle.' 

Leicester. Feb. 19. 1918. 

PLATE SIZES. 
To the Editore. 

Gentlemen. 1 agree with those of your correspondents who object 

to the present standard sizes of plates. 

Twelve years' practice with a half-plate and stereo field camera 
ha,s convinced me that the 7^ in. x 5 in. is much more pleasant in 
use than the half-plate, both for landscape and portraiture. One 
of the chief joys in my photography is the composing of the picture 
on the ground glass, and for this the 7^ in. x 5 in. has, I find, easily 
the advantage over the half-plate. 

It may interest your correspondents to know that a large number 
. ! .-tudents. when requested to divide a given straight line into two 
parts, whose proportions should bear the most pleasing relations 
to one another, made tl\e ratio (on the average) 1.6 to 1 (James's 
" Psychology "). This is not far away from the 1.5 to 1 as recom- 
mended by 80 many of your correspondents. — Yours faithfully. 

C.\LYPSO. 



DEVELOPER FOR PROCESS WORK. 
To the Editors. 

Gentlemen, — The ))hoto-mechanical press is at present not in a 
I H isition to give assistance, so please allorw me, through your 
iiodium. to help my fellow half-tone operators. 

.\cetic acid is still fairly easily obtainable, but spirit is a vanishing 

rticle. A substitute for the acid-spirit-iron developer has been 

I commended, viz., an acid-sulphuric and gelatine-iron mixture. I 

I inid the latter wanting; the developer give» irregular density, 

id the after intensification is very trying — in fact, two or three 
- ifcessive intensifications are required. 

After a few trials I can recommend the following : — 

A. Stock solution : Gelatine 2 ounces. 

Acetic acid 99 per cent 20 ounces. 

Water 30 ounces. 

B. Developer: Iron sulph 4 ounces. 

Stock sol., A 3 ounces. 

Water 50 ounces. 

It will be iiuiiced that the amount of acetic acid is less than half 
that generally used in spirit sol., because the gelatine al.so acts 
.1^ reslrainer. The resulting ivegative is every bit as good with 
; lis new developer as with the older one, especially if used slightly 
. irm. and before pouring on should be freetl of bubbles; the stages 
I I ring initensification are visible and easily accomplished. 



I use ordinary gelatine. wJiat I may call best glue, and not 
]ihotographic gelatine. 

If acetic acid should become still more scarce, a substitute would 
be vinegar, which can easily be made from apple or pear juic& 
obtained from windfalls or otherwise ; such vinegar contains 5 tf> 
10 per cent, of acetic acid. If information is required to make such 
vinegar, I shiill be pleased to give it. 

The a.b(>ve A 6to<k solution is also a first-rate substitute for gum 
on wet plate, giving a perfect protection and a .surface which takes 
the pencil easier and better than any other medium I know of. 

Otto Pff.nxinger. 



HYPO RECOVERY. 

To the Editors. 

Gentlemen, — Durin;; rhe last few days I have been making a scrie- 
of experiments with the object of the recovery of sodium thiosul- 
phate from exhausted iixing baihs. Thinking that the results of 
my experiments might be of some general interest. I am sending you 
an account of them. 

In the first place, all the experiments were conducted with a plain 
"hypo" bath, and do not apply to acid batlis. My method was to 
pre<'ipitate the silver by pa-ssing sulphuretted hydrogen gas through 
the solution in the presence of ammonia (ammonium hydrate). The 
silver sulphide was then filtered out and the excess of sulphuretted 
hydrogen and ammonia boiled off. The strength of the hypo solu- 
tion was mea.sured by finding the time taken by a definite volume- 
of the solution to clear a strip of photographit- film of a definite size. 
The results were o-s follows : — 

The fresh solution cleared the test film in 18 minutes. The solu- 
tion %va.s then partially exhaiisted, until the time taken was 45 
minutes to clear a film of the same size. At this .-itage the precipi- 
tation of the silver was carried out as described above, and the 
" hvpo " solution wa.s brought to the same volume as before by the 
addition of water to replace that lost by evaporation. I now found 
that the tes-t film required 22 minutes to clear, a result showing that 
the activity of the bath had been increased in the ratio of slightly 
more than 2 :1. 

You will notice that it had not quite regained the strength of the 
fresh solution, but this was probably due to the loss of a small 
quantity f.f the hypo by adherence to the films. 

At the time of writing my ex|)eriments have not gone far enough 
to give a full explanation of the chemical processes involved, but 
I think it probable that a double thiosulphate of sodium and 
ammonium is formed in place of the one of sodium and silver. In 
practice I see no reason why ammonium sulphide should not be 
substituted for the sulphuretted hydrogen gas if desired. — I am, 
yours faithfully, L. F. E. Johnson. 

Highbury Grange, N. 



ECONOMY IN HYPO. 
To the Editors. 

Gentlemen, — In these days of stress and increasing difficulties, any 
practical suggestions for the economising of either materials or 
labour should be acceptable to all photographers ; so that, following 
upon the remarks of the editors in recent issues anent the possibility 
of effecting economy in the use of hypo, my experience and observa- 
tions in this direction may be of interest. 

My usual practice is to eni))loy porcelain tanks for the fixing 
bath for plates ; and I have noticed that when a new hypo bath 
is in use the plates completely fix out first at the bottom edge and 
thence gradually towards the top. But, as the bath becomes charged, 
with residual silver, the fixing out of the free silver in the negative 
becomes slower and slower near the bottom edge of the plate, until 
the upper part becomes fixed in half the time necessary for the 
complete fixation of the lower portions. If the bath, when in this 
apparently exhausted condition, is stirred up immediately before 
piitthig a plate in, fixation i.-i practically even all over, and the 
time for complete fixation is reduced. 

This observation led me to deduce that if a much-used fixing 
bath which had been standing undisturbed for, say, twenty hours, 
had about three-parts of the whole carefully decanted off into a 
dish, a.id the residue thrown into the collecting tub, the decanted 



THE BRITISH JOURNAL OF PHOfOGR-VPHV 



107 



its original efficiency by 
nen 30 per cent, hypo 



'jtfon would be brKiuhr »' nrieii. 
it ap to 

. And til.- i ; 

!Io«* tb&t hypo lued for priotc may be treated in the same 

-irul the saving of hypo be enomioos. A hypo bath may 

<> treated in this manner two or three times before 

It'd aa a first bath, when it can still be nsed (or several 

of prints as a second bath. For the complete fixation of 

■ *■- 'I'M- of a second or even a tliird fixing bath cannot be 

■•il. The individual .sr|iii itiun of the prints when 

"lie bath to another is, of course, essential. It is also 

ccasioiially to put a print through the solpbide teat 

■■• -t:on. 

)x> may be further effected, and much labour 

i-u. (1..H v.iiaiiy by singl. ' — -" ' jrinters ia bromide, by the 

' of a stop bath when (i I have made inquiry, and 

1 that very few photograpiier.-. know of the great advantage of 

' use of a saitabla stop bath. In wintry weather, when the 

umperature of tap-water wavers around frecxing point, the stop 

bath is a friend I would not be without for gold. As a roeaits of 

' -ping the fixing bath free from develoi-er it is perfectly effective. 

'ar many experimeats, with the partn-ulars of which I will not 

1, I have decided that tartaric acid OMkes the best batii 

purpose. Dim oinioe of tartaric acid cttsUI* diasolved in 

<>ui)c«a of water ia aafltcient for SOO halt-plate priata or post- 

lis. The ;>r^-edare for use is as follows: — A batch of, say, lOO 

~' -><e prints are pl^onl in a pile, eonvenienCy 

' hand, and on hut for her) left is placed a 

tj^ 12— dish contain tcid solation. 

. mI two at a time >: at intervals 

I as developmeiit u completed the developer 

•od the prints tranafened to the slop balh. 

hvr devalopment, until the whole of the batch 

I. In this way ronsidcrably more thma 200 print* 

. developed in an hour. The batch ia then placed 

nmaing water and the priala tamed face down- 

lie at a tune. When all have been ao ireatsd they should 

I op rrt s batch and allowed to drain en the Ml hand whili- 

ine at a time into llx- firat hypo fi- 

method lor dealing uith a Unci of 

,.. handed is to get the whole of the day's 

•immeaeing develofMMnt of anything morv 

! roeeading as detaiUd above until all 

\« the strip K-rth (ftta overcrowded, lift 

^1 draining, drop 

,.;h nf witter and 

- of the 

" hatch 

■f hypii 

:i to the 

- m this way 



!0. Rnasetl Mreet, iilraad. lilu*. 



Hxrar J. COMI.BT. 



>irxMxa TiMC M*krH 24.— Tha Home Sseirtary haa announced 

the Hoaaa of Commnns thai aamm- ' ~ ~ "M be brought into 

e thw year on the m'Tnii^ of Snn<! . 24, and will cnn- 

le nntil the night ol Sanday, 8si>trtTi!..r £^ a penxd of twenty- 

weeks. Thw is a soaiewhat lonnr |>«-riod than last year, when 

i4>gan oa the seeood S \ 1 and ended on the 

in September. Thr \ , in coming to a 

Had to take into eonskdcri' "H tOe rxcaptional rirrum- 

■' prseeat year. The shortage of foods make* it a 

' iai(iortaaee to increase aa much as pooaible the 

1 on alloliaaata. The Coal Conimller also, with 

.kppnjval of his Adviw.ry Board, whi ' ■■ ■. repre 

•h» Miners' Federation lia» in vi«» Vicultiee 

•h« naceasit' I, urged strongly 

■•mentofn. to reduce the con- ^ 

■ of ^«« and eiectncity. 1 U- h have been fixed 

»n nrlditinnal five weeks of -'^ this year, and 

•luse no eei iua e incoi claai. The 

~ to be tegsrded se ai' •sore (or the 

■■nl oatjttBikl 



JinsiDers to CorrespondentSs 



In 



to Co 



SPECIAL NOTICE. 

f ivpplifji of paper, as the, rrfulr 

. "m n of much leo nd pulp and grans. 

wiU^e a vnilable until further notice for rr plite^ 

■ .,„.„„■ lits. 



Mortovtr, ye will anfwtr by pott if stamped and addreutd rni e- 

lope it enclosed for reply: &-etnt International C oupon, ifrom 

readert abroad . 
The full qvettiont and nnsteeri wUl be printed nnty in the eaxr of 

imqttiriet of general interest. 
Queriet to be anstcered i;i the Friday's " Journal " must reach us 
than Tuesday [potfd Monda y), and thould b e 

^ to the Editors . 

FmaoTTTE.— Theee plates are usually ooated with collodion eraul 
sioo. It would take \xy too much apace to give detailed ingtrui 
tKNU, and then a year or two's experiment Avould probably In 
neceaurv before you turned oat a decent pLite. You might 
write to Penr <•• and Co . Farringdon Ro<id, to inquire if tlie\ 
<" -i<n. 

^•" VHD8.— How can I glaze bromide podtcard.- 

on )$iiHij. vrrj >.imply, as I cannot get methylated spirits now?— 
W A. H 

I'be gUas roust, of course, be perfectly clean, and the cards 
hardened in a formalin or alon bath. iSeftu-e iwiuet^eeing tihe 
cards doan the glasses should be rubbed over with a pad satii- 
tated with prepared ox-gall or one of the advertised glariim 
oDlulioas. The glsases, with the cards on, should then bo taken 
into a fairiy warm room and kept at an even t«niperature until 
the cards drop off. 

P1.HR0LCS IN R ■'■ vn SHtrma.— I should be much indebted^ 

to yo<i if y..i, iiir .idvii-e with reapec< to the following :— 

I have a " .S<-t*«M i.- ,' i.l.i!.. <amer», the blind of which haa 
baeone cowered with p !■ the Wind having a tendency to 
ciaek throogb winding on roller. Coull you tell me how to fill 
in Um holea ao as to make the blind eiBcieiit ?— J. 8. B. 

The only thiitg to do abort of fitting a new hjind is to max up 
soma lamp-black with rubber solution and rtA it into the hnlee 
on ' Allow it to dry as long as possible and then dtwt 

a h chalk over to prevent sticking. 

!•>: ■. pMOTOciuniT.— Yna will g»i a good general know- 

It' otographic proceseea and principles of leasee fjxtm 

" Pbut«vraphy of To day," by Cliapman Jones, or, by the same- 
author, " Scieucc and Practice of Pbotograpliy. " Our pub- 
liihers also »apply two email mnniials. " Commercial Phulo 
graphy " and the " Portrait Sladio," which both contain a gmid 
deal of information in a condensed form. We belteve that Hi'- 
Rqgeot Streot Pulyteciinic will give poetal leosoos Yon ahouli 
writa in Mr. A. J. Lyddon. School of Photography, Polytechnic 
Begent Street, W., stating the particniMr . subjeota for wiiicib you 
require leasooe. 

l.lKsu, — 1. Will you kindly inform me what extension of camer.i 
kluuld I rr«|uire with a lens of focal length of 12 ine. or 14 ins. ' 
2. Would you advise a 12 in. leoa, rectilinear type, for profe^ 
•tonal work?— Thomas Batv. 

,^l^Tha 12 ins. lens would need an extension of at leaat 15 inn. . 
aOo 1mi4 -ins. one of at leaat 17 ins. for ordinary purposea. Voii 
eoold get quarter full-size images v ith Uiem extensiona, whii.^ 
bigger images would need still more. 

2. We should say it is far too long a focus unless you can get 
a long way off, and then you would need good Ught. MiKili 
better to uae an 8 in. ansotigmat. 

H>xo-Co*Ti.<(0 Platxs.— T%e eoafasotway to coat platee by hand ii^ 
U< ke<-p the warm emulsion in a small Japanese teapot, having 
prtnldi-d yourself with two or threo levelling stands (eadi made 
by putting three screw -eyes into a piece of wood and screwing' 
thesn in lustil a plate on them is truly level) and a glass rod benr 
into a triangle. PtA a plate on the levelling stand, pour oo the 



108 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



LMaixh 1, 1918. 



requisite <|U8nUty of einiilsioii, spread with the glass rod, and 
allow to sot. By the time ynu have coated three platee — at this 
time of the year — the first should be set enough for the drying 
box. The plates should not be too fold, or the gelatine will set 
before yi)U can spread it. Put on no more than is necessary, so 
that there is no surplus to pour off. 
AiiTiriciAL LiOHT. — What would be tihe most suitable Light for 
taking photos in a room 20 ft. x 7 ft. x 7 ft. ihigh,? It is on 
the ground floor. I want to turn it into a studio principally for 
postcards and stickyback size. My camera is a half-plate, R.R. 
lens, working .'it f. 8 largest aperture. — E. S. 

If electric current is available, .half-waAt lamps or an enclosed 
arc. Toplight pattern, would be the most suitaible. Otliei-wnse 
you must use incandescent gas or the Kitson or Blanchard oil 
light. But either gas or oil lamps will make a small room very 
hot unless you have exceptionally good ventilation. You migibt 
try the Tress " Surelight." whicli, is a comibinalion of igas for 
focussing and flashlight for exposure. 

PHOTOGRArHic CHEMISTRY. — Is there a photographic or chemical 
work dealing with the chemical tquations involved wh>?n light, 
developer, or hypo comes in contact with modern emulsions? — J. H. 
The action of lif;ht cannot be described by chemical equations, 
while that of the developer cannot be expressed in detail. Rather 
more definite informatitn exists with regard to the action of hypo, 
but even here the precise course of events is somewhat involved 
and not exactly known For such general matters as these you 
had better study Mees and Sheppard's "Investigations on the 
Photographic Processes." With regard to fixing, ypu will also 
get some useful information in the paper Jby Lumiere and Seyewetz 
which appeared in the "B.J." for August 16, 1907. 
r>>NSES. — 1. What lens is suitable to take photograph of room of 
short length ? Quarter-plate size would suffice. 

2. To copy same size, or enlarge from small photo (print) on 
to a whole-iplale. what lens is suit/able so as to avoid placing the 
camera so near the object as to interfere with the lighting of the 
print to be copied or enlarged ? — C. 

1. If you wish to include a wide angle you should use about 
a 3-in. lens, such as the Dallmeyer wide-augle rectilinear stereo 
lens (3-in.), or most of the modern anastjigmats would be suitable. 

2. We have, found a 65-in. or 7-in. anastigmat most con- 
venient for this purpose. If you have sufficient bellows exten- 
sion, a 9-in. would be better. It is a good plan when enlarging 
to fit the lens to a small cone extension, as this does not cut off 
so much light. 

Condenser Sweating. — ^Would you kindly advise me in regard to 
an enlarging lantern, which I have just purchased. I find on 
using that the condenser (8^-inch) sweats very badly. 1 have tried 
the upright incandescent mantle, also the inverted, but without 
success. It seems better when I have the metal back of the lamip 
house removed, hut condenses again directly I cover the back 
•with material, even. Is there a preparation I could make up to 
prevent this sweating of the condenser? Your valuable advice 
will be greatly esteemed. — S. T. 

The " sweating " of the condenser is due to the glass being 
cold. If you warm it well before the fire or over a ^tove jou -vill 
not find this trouble ; the condensed moisture will evaporate more 
quickly if some holes are bored in the metal ring which hoiJs 
the gl isses. If you cannot ■warm the condenser otherwise, light 
up the lantern, say, half an hour before using. When the con- 
denser is warm the " Steaming " will dlear off. It i.-i of little use 
to try to wipe off the moisture. 

Re.'sidl'es. — In saving the old hypo baths, will you please say 
whether the sodium sulphide, after being used for toning, would 
be sufficient in itself for throwuig down all the residue? — Rex. 

No. The solutijn is far "too weak for this purpose. You need 
a strong .solution of sulphide, or it is better still to throw in the 
undissolved crystals. There is no need to worry about a solution 
until the time comes for testing. 

X. — 1. Y'cs. 2. All a matter of taste and dependent on subject. 

.3. Any angle in excess of that required to cover the plate is likely 

to produce fcg, hence the use of lens hoods. 4. Focus on a 

pinhole with a bright light behind it and see' what kind of image 

U pi-..r|iir.,.H. 5. This ii wc'.l knoivn R.R. lens of fairly useful 



me an order 
for an adver- 

matter detail- 
printed on the 



quality. 6. We believe it to be an excellent lens for out-of-focui 
work, but (Joubt if any stopping down will make it w(jrk like ai 
R.R. You should address a question of this kind to the maker 
7. We do not understand this query. Too great a focal loigtl 
generally involves too great an angle as well. 8. If you cannol 
change the panel the only alternative is to get an adjustable leni 
flange. 
Rkmoving Printer's Ink. — A customer gave 
for 600 12 in. by 10 in. enlargements 
tising scheme he had in hand. Printed 
ing the nature of the subjects had to be 
mounts by a printer as per his (my customer's) instructions, also 
the word " copyright " had to be written on each in writing ink. 1 
had the 600 12 in. by 10 in. mounts, which were " cream on grey," 
printed by printer, also had the word " copyright " written on 
, each tint in writing ink. I supplied 100 copies to him with 
enlargements mounted on same. He seemed well pleased with 
same at the time. Recently I have received a communication 
from him cancelling the rest of order, stating that, owing to un- 
foreseen circumstances, he will not be able to carry out the scheme 
lie had on hand. I am now left with just over 500 12 in. by 10 in. 
cream on grey mounts, which I cannot use, owing to same contain- 
ing printed matter, printer's ink, and ordinary writing ink. 
Can you suggest any means, chemically, etc., which would enable 
me to remove the inks, the prniter's ink and the writing ink, on 
tints of mounts? Have tried turpentine and salt,^ also o.xalio acid, 
but these do not seem to be effective. I should, if possible, like 
to remove inks without injuring the mounts, so that I can use 
mounts for various enlargements, etc. Your advice on this 
matter, or some of your correspondents, would be greatly 
esteemed. — Anxious. 

We know of no way of removing printer's ink, and yqu could 
not deal with the writing ink in any way that would not show on 
the delicate surface of a mount. Y'our customer ought to pay for 
the mounts that have been wasted in this fashion, even if he 
does not want the enlargements, and if you had a firm order to' 
prepare 500 you have quite sufficient grounds for demanding the 
money. The cost 01 the 500 mounts should not be great compared 
with that of the 500 enlargements that he has countermanded. 



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/M 



THE BRITISH 



JOUMAL OF PHOTOGEAPHT. 



3018. Vol. LXV. 



FRIDAY, MARCH 8, 1918. 



Pkicb Twopence. 



r 



»C*l 



Contents. 



»•■ 

m 
uo 

> PiomiM or Pwm>- 

Bolbaakj.. lU 
or L>su« 

lis 

116 

■ KsaiacTMa* lU 



r>os 

McimBM or iMmiaa 116 

r»»Bi>' 111. »■> t>i«AL lanrnui- 

•ncE UT 

Ren A«i' NoiBS 117 

Htxri "iiu Hm- 

lUi ; .:. 8U» IK 

:r I'oUoDiac 1» 

loOmmmtmmmn.... 119 



SUMMARY. 



Moond porttoo o( llie paprr by MraJn. E. Di Tillycr knd 
' 't/. o< 41m UuiUd tHain Bvimu ot B t i n dtrd*. fptmn 

vhcTC in diatrieto «&*r« the walvr 
no m—iw b* dtaMUMd w • factor 
print* (p. 100). 

.twth Ttmil I Taylor Mcfoorial !.«- 

-^.. i.'.^.Html^ d««U wilib rtdaetiao. alkali 

i> intenvirimtioo. and intaaaiftcation and lon- 

. {imm*. will ba (oand oo pafa 111. 

> cnaaid«Trd in reUtioD to th* pvofinttioa of the 

.. .. .irr likrly to be pl«c«4 on thMI ara d«ah with in 

1 on page 110. 



>'no«td*wM» anopomy in tl»» "*• "' nlw*. 
of ■tap rxpoaum 
~ Ml f «r 



.1 



100. 



l«r, 



Th* 



• n. 



adapting: 
ject of an aitide on pa(e 110. 
g kypo ia raferrrd t« afain in two pan- 

n( war |>hntograph« in roloitr «l tife Onflnn 
appeals U> Iw that >•( Mpia toning loUowed 
: tlie aarafispli (p. 116) 

imder Hw Defence of the Baalm recalatton*. 

■U<nt>by and ikatohine witbia certain of the 

lea the .MetropoliUa police dMrict. ia 



iio racorery. pl»U aiaaa, and devflo^r 
. of Utters from na raapondant* 'p 118> 

trade and teohntcaki joumala «•( at 
M«TnHmi>nl of tltr Board of Tmde r>i 

linf a laree noabar of aaisplaa of 
X tbeae exlabiu yh O ographie (ooda 

■•triaa Fair, at which pha«ogia(>hy 
-"un OB page 117. 

"■tcativ ^nd nnt plaoDg Uw much 
the rabject of a 

and 
-wera 



A r.-f..'^ '.f a Trihnnal appMl, in whieh th* decision appears lo 
r»th<T K»rHIv on a photoftTapher wtw i« serriog hia country. 
L. f ._.s -.. - iia 



EX CATHEDRA. 

Reolaimintf It is interesting to note that, following 

**yP**« our paraj^'riiph of a week ago, the recovery 

of hypo from spent fixing iMiths baa engaged tbe attention of 
correeponclents. ' The thn)wiDg down of the silver with 
sulphide is the moet obvious mctbcxl from the chemical 
standpoint, and of tbe various forma in which .sulphide cuti 
be used hydrogen sulphide gits is chemically the bi-st, as it 
IS praotically tbe most unsuitable for tbe average photo- 
grapher. But, lookmg at the matter simjjly from the 
experimental standpoint, which is all that can be done at 
preaeni, no nsi'ful purjose is served, wo think, in adding 
ammonia along with the hydrogen sulphide ; certainly none 
if it IS contemplated to get rid of the excess of hydrogen 
salphido by boiling. The ammonium sulphide which is formed 
is mach lesa easily disaociiitiil. So far as we can see there 
is little '■""' '— these sulphide methods of regenerating hyixj 
unless can hit u|ton a reagent — oiidiser or re<lucer 

— u' ^niiocaous in itself, and is also capaU>> of sharply 

c<<: ibe excess of sulphide into an inert IxKly whilst 

leaviu;; the hypo itself untoucbe<l. 



Economy in Mr. H. J. Coml«y'8 letter in our issue 
Hypo. of March 1 draws attention to a very 

practical point in hypo eoonomj. It is a fact, as h^ says, 
that hypo has a great tendency to sink in solution, while 
partially exhausted hypo, being still heavier, tends to 
Bcvumulate at the bottom of the fixing veseel. We haN'e 
just had a striking instance of this in the case of a very 
badly exhausted bath, which still possessed fixing power 
near its upper surface, but none at all in its lower layers. 
If a bath is perfectly clean but just beginning to slow 
down in its nxing qualities, it is a simple and safe ex- 
pedient to let it stand overnight in a suitable vessel, and 
in the morning draw off the upper halif for addition to ne / 
bath, while the lower half goes to tbe residue tub. 
Mr. CaoiUf^s practical experience i^ so great that his 
advice in this matter, and also in that of the all-im- 
portAnt stop bath, is worth careful consideration. It is, 
however, to be feared that many modem workers are very 
indifferent to tbe cleanliness of their fixing hath, and are 
just as loth to use a stop bath ae they are to use a clearing 
bath, though the advantages of both are distinctly 
apparent. 



Bliatera and 
Town Water. 



We cannot but think that had Mr. John 
H. 0«ar numbered among the privileges 
of hn life that of living in Birmingham or Glasgow he 
would not have dismissed the quality of the wash-'water as 
a factor in the blistering of prints so ItghtJy as he did at 
a recent meeting of the Royal Photographic Society. He 
there stated that " he did not believe that there was a 



no 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[Maroh 8, 1918. 



sufficient difference in town water to cause blistering in 
one case and not in another." Perhaps he and we have 
a different idea of hhstering: a subsequent passage 
sugge-sts the occurrence of blisters by mishandling of 
prints. We have in mind when we speak of blisters a 
ca-op of minute pin-point ai bells beneath the emulsion 
film, and it is certainly within our experience that photo- 
graphers compelled to use water almost as soft as that 
obtained by distillation — and the water from the Welsh 
hills and the Scotch lochs answers to this description — 
find it by no means a negligible factor in working emulsion 
papers -without blistering. If we remember right, it was 
Mr. Harold Baker, of Birmingham, who first consistently 
laid emphasis on the need of special hardening baths, as an 
offset to wash-water of this kind, when sulphide toning 
first began to come into general use. 
♦ » ♦ 

Business The announcement that the School of 

Management. Technology at Manchester is abO'ut to 
establish a lectureehip on Business Management, and to 
encourage study and research in this most important 
matter, is distinctly a good sign of the times, for, up to 
the present, business managers have too often seemed to 
trust rather to instinct than the training for the details 
of their work, the natural result being not a few dismal 
•failures. It is to be hoped that every encouragement will 
be given to the research aspect of the matter, for business 
management is by no means a cut-and-dried science that 
can be taught like a branch of mathematics. It includes 
complex matters like that of costing, for example, which 
in iteelf is a subject that no one can claim to have 
mastered ; and also economics, which has been a favourite 
plaything of politicians and philosophers for many years, 
and has been not a little confused by numerous false 
prophets. In both these suhjects there are many points 
that can never be reduced to matters of rule, and both 
need .the most careful and unprejudiced study and research 
from numerous points of view. We would suggest that 
it would be very advisable to include among the lecturers 
some who are familiar with the bigger aspects of economics 
as they affect the world in general, and world finance and 
prices in particular. A quite false view is often obtained 
by considering such questions as they affect one or more 
trades only, and the bigger and broader aspect of the 
matter is as important as the study of " big maps " is said 
to be to strategists. 

» * » 

Plate Sizes. A recent letter on this subject by 
" Calypso " makes reference to an in- 
teresting point. He mentions that a number of students 
when asked to divide a line into two portions that should 
bear the most pleasing relations to one another made the 
ratio 1.6 to 1. A better test than this is to draw a 
rectangle that shows the most pleasing proportions, and 
if due care is given to the operation and a sufficient 
number of trials is made the almost invariable result wil 
be a rectangle of the proportions of 3 to 2, placed horizon- 
tally. This is not purely a matter of psychology, but one 
that can be explained in a very large measure by simply 
studying the phenomena and mechanism of vision. It is, 
no doubt, a result of this phenomenon (if we may call it so) 
that so many seem to think that 3 x 2 are the best pro- 
portions for plates, but there are further points to con- 
sider. _ If when we have drawn such a rectangle we proceed 
to divide it up, say by one straight line in any direction, 
we shall very likely find that the result is then far from 
pkasing, and we shall not only have to be extremely care- 
ful where we place the line, but will also very likely feel 
oompelled to alter the proportions of the whole thing. As 



a matter of fact the most pleasing proportions for any 
kind of picture depend on the picture, and on the way in 
which its lines and masses cut up, or fill, the space. No 
one ratio of width to height will suit all suJbjects, and 
every careful landscape worker will appreciate this fact. 
In portraiture variations are not so often needed. Head 
studies and full lengths will need different proportions, 
but the former will usually fit very pleasingly into a 4 x 3 
or 3 X 2 space, while the latter will nearly all fit well into 
one or two stock proportions. The 4x3 ratio seems to have 
been derived from paintings, painters usually adopting 
this ratio for portraits. It is, however, undoubtedly too 
square for a horizontal rectangle, and 3 x 2 is much more 
generally useful, though trimming is an operation that we 
can never dispense with. 



TKIAL EXPOSURES AND BCJONOMY. 

In these days when universal economy is rapidly becoming 
a matter of necessity there is no detail of daily practice 
that is not worth investigating from the waste-saving point 
of view, and one very important detail is certainly that of 
trial exposures. In spite of the fact that numberless 
methods of estimating correct exposure exist, it is neverthe- 
less a fact that in a vast number of cases workers prefer an 
actual trial, and experience shows that, after all, nothing is 
so absolutely reliable as this expedient. In most cases, 
however, the trial is made on a full-size plate or full-size 
piece of paper, the operator thinking that if this first trial 
proves a success he will have saved material. He will, of 
course, have done so, but the odds, in our experience, are 
against the success of the first attempt. It may be mode- 
rately good, but not so good as it should be, in which case 
quality suffers; or it may be bad altogether, which means 
that on this one trial sufficient material has been wasted 
for several trials. Indeed, it not infrequently happens 
that on the first trial proving a failure the second is not 
exactly a success, so that a third becomes necessary, and 
this doubles or trebles the waste. 

The mistake, of course, consists in attempting to do 
things by halves; instead of weakly hoping that the first 
attempt will prove a success it is far better to decide 
definitely that it is to be a trial exposure, and nothing else ; 
in which case we need not use a larger plate or piece of 
paper than is necessary for an efficient trial, while we oau 
make a series of exposures in steps, so as to make sure of 
gathering definite information. The material used in tliis 
way is not wasted, because from it we gather definite and 
important information. 

A trial of this type is very necessary in enlarging, while 
it is extremely useful in copying work when we have not 
the advantages of standardised illumination, etc. It is 
also sometimes useful for getting critical focus when this is 
essential, in which case we can test the effect in one or two 
positions of the focussing screen, both inside and outside 
the one position that, visually, appears to be correct. Thus 
we sometimes need trial exposures on printing paper and 
sometimes on plates. The former case is easy to deal with, 
and the most economical way of making due provision for 
such trials is to take a few sheets of paper belonging to one 
particular batch, cut them up into suitable strips, and 
store them ready for use in a special box. Paper-makers 
generally include in each packet of cut papers one small 
piece especially for trials ; thus in a 10 by 8 packet we may 
find a 5 by 4 separate piece inserted for this purpose. As a 
matter of fact, these are seldom so satisfactory as longeir 
strips, and so, as a rule, we prefer to collect and store the 
small pieces for making small prints, and cut up one of the 
bigger sheets into strips for trials. There is no extra waste 
here, because one 10 by 8 sheet will probably suffice to give 



Manih 8. 1918.] 



THE BRITISH JOdRNAL OF PHOTOGRAPHY. 



Ill 



1 the strips required for four packets of paper, whereas 
the four 5 by 4 pieces provided can do no more, and will 
probably not do so much, with the same efficiency. 

>• use of trial strips in the case of bromide paper 
:uiiioii, very seldom do we see the same expedient 
;i the camera. Though half a quarter-plate is as 
t for a trial as a complete one, yet few will hesitate 
to use the latter, whiie we have even seen three 10 by 8 
plat«a wasted in the attempt to arrive at the exact best 
exposure on a special subject, thoui;h a quarter of one plate 
would have been sufficient. The alternative to employing 
strips of large plates for trial pur^Mses is to use a small 
plate in a carrier. It seldom nappens, however, that a 
small plate coated from the same batch of emulsion is avail- 
able, while in any case the mere • if the effect pro- 
duced ill the centre of a large pla' iii adequate test 
for the margins, which' may require just a little more 
exposure, or. perhaps, a reduction of the stop aperture to 
set-ure • illumination. Nothing is so reliable 
as a h-: will reach the margins; therefore it is 
be>' ' ' ^ifice one plate at the start for the provision of 

Plate strips must be cut the long way of the plate, as the 
Iv means of giving a series of expoeurcs in stripe is to 
ike use of the shutter of the .slide, which invariably 
.W8 out longways. A 10 by 8 plate will make four ser- 



viceable 10 by 2 strips, and if we provide also two 10 by 3 
strips, cut from an old useless negative or spoiled plate, 
or from stiff millboard, it is an easy matter to load the 
slide with a trial strip centrally. It is a good plan to keep 
the cut strips in a plate box fitted with a central division, so 
that the trial strips can be kept in one side and the packing- 
up strips ill the other. Lf these latter are of glass, they can 
be covered with paper gummed on, and then they can be 
distinguished from the trial strips by touch. If one feels 
reluctant to cut up a plate into four trial strips on the 
ground that two or three may never be needed, a little in- 
genuity in mapping out the plate will provide one or two 
trial strips and one or two plates of smaller size. Thus a 
10 by 8 will cut into two 10 by 2 strips and two 5 by 4 
plates ; or into one 10 by 1^ trial strip, two full-size stereo 
plates, GJ by 3}, and two lantern plates, size 3^ by 3^. 
Other size plates will cut up differently, but when possible 
it is best to arrange matters so that pairs of smaller plates 
i-aii be produced, as these are more safely stored than 
single plat4B if packed faoe to face. We may add one more 
case in which trial exposures on strips are very useful, and 
that is when preparing bromides that are to be sulphide 
. toned. Verv much here depends on the printing e.xposure, 
and if a strip ia prepared and put through the sulphiding 
process the ^>est possible results can be secured with 
certainty. 



SOME MINOR PROCESSES OF PHOTOGRAPHY. 



(The Twentieth Traill-Taylor Memorial Lecture «iellTer*d before the Itoyal Photographic Society by C. U. Bothaiuley, 

M.8o.. F.l.C.) 



Ms J Taaiu-TArMm, in ■wWmn' menwty thin lect*u» was 

'•l-<i. had an •>. .- with all faiwidMa of 

' ".'raithy a« : i.>v H« made a sfiedal 

! phoAograpiNc optm ai a Unu- when that branch of 

•i^v waa <ia(nparathelr neglert«<i in tki« ooantrj, and 

-otiurntiv his naau» has ahrav* brvn aaKciat«d more psr- 

Isrij with thow atodics. I faeli«va it m correct to aaj 

almoi* aU the i>revioaB m««iortal leetevM have dealt with 

• wcaion tjf iiptiral ph)-nrmi<-na. or, at any rat«, with aome 

'ich of fhymrt. .Mr Tsrl<>r\ kn'iwledgc and (TnipalliLies 

•■. ho«wwr, by no m«aii« v -1. Those who kn«>w 

will i«» ni eiid»r that ht< w.t- intrmti'd in all the 

■^rigraiphic practice Kml had an almoot uncanny 

with Iht ori^n and hixtorr of rarious pnxmcs. 

I claim to ciManiral knowledge, and I was never 

>•• HUM <nit to what ext<>nt be waa a ohsmiift ; tint it ia 

. wi>rlh> that hi^ name appear* n» the re«p«ini>iblf editor 

">"» " Photograph ir <*h««ni»trj-,*' 

• T»*>)e ifrt#f»»»«, ami n carnful 

■i«rt«-,<rii-«." juat 

■_\ year* aeo that 

err \ »epe merelr th«- rvanlts 

"I "f (oripiU«> information 

gn>at " HandlM«* of ObMnistry." 

.'? the«e f*-t* that |«d me to think, 

rii'ir of th^ iiivilatiun to (l«4iver this 

.' before you 

'f cnreiyda'y 

'f the extent to 

' !•<• of office staff 

■I w.»rk wli >t to so many of 

.1 aiJmit. I ; ■•,,t the invitation, 

I I have to beg yaar indiUi;>'noe if •nme of my experiments 

... ►,. ...^....pi^te, and to a»k you to regard ihe results aa 

loafer on I hope to ba able Ut carry the 

'n.r :n r«Ttain dircctkiBS. 



I ppofKNs to deal with three well-known prooeeses — namely 
(•) I--' >ith alkali persulphates ; (2) int«isifioifion witli 

th.' ,1 . aaaiujii bichromate ; and (3) inteiuiiiioatioii and 

"toning ' wrth potassium ferricj-anide as tlio intenni-diary, 
tn\ <il>j(^-t iLteing to clear up attain discrapancics between pufc- 
liohed tt.itemrnt* and to ascertain what are thtf real essentials 
t'j Kuci-r>*lul wurking. To thiit end I have taken special care to 
ii»e rheniiralt of a verj- high degree of purity, and to wash all 
•olublr »alts out of the negatives or positives experimented on, 
u*in>; carefully distilled water for the final washings.' 

1 lie ni^gatives (or 'pimitives) experimontt-d with were a very 
mixi«l If* of (dbjecta ; many of tliem were not made by me, 
V of thfm were several ymrs old. Some had been 
'I ,1 with pvro-aoda, woate with hydroquinone, and some 

»ith mi'tiil-hydroquinone, so that, as a whole, they pro\'ided 
Miff'iri<qit \-ariety. .\ll were soaked in water for at least twenty- 
four houta before heing treated with any chemical reagent. 

Thu atrip negatives made in the course of the experiments 
wrrp 4evek>|x«l with diamidophenol and aodtum sulphite with- 
out .bromidr. 

Ammonium Persulphate. 

Th<> alkali |>er»ulphat<-« wen- first preparerl in 1891 by the 
lat«' Dr. Hugh Mandiall, who obwrved that their properties 
iiirliillKd {tie power, when in aqueous solution, of diisolring 
fin«-l\ divided silver Irr converting it into silver sulphate, the 
alkali persulphate being reduced to sulphate at the same time. 
It was obser^'ed later that this change goes on more rapidly 
after mnie silver has already passed into solutdoni, and tlie 
rat< of the reaction can be markedly accelerated fron the out- 
nol if a small quantity of a sui table soluble silver salt is added 
to the /persulphate solution before it is poured an the metallic 
Nilver. The practical importance of this fact will be referred 
to later. It was also found that the aqueous solutions of th^ 
pciKulphates alone gradually decompose when kept even al the 

last wMb-walsr was slwaTt tMtcd ittat It had bata la eoataetwllh tba 



■ Tb« 
ItaiTo* 



112 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[March 8, 1918. 



ordinary temperature, oxygon .being liberated whilst alkali 
Bulphato and sulphuric acid remain in the liquid. The eolu- 
tiona of ammonium and potassium persulphate are neutral to 
litmus when freshly prepared without the aid of heat, but 
gradually become more and more acid on keeping. 

In 1898 the use of alkali p<>rsulphate« as reducers for photo- 
graphic images was proposed by MM. Lumi^re, on the ground 
tfiat they not only dissolve the silver image, but do so in a 
jieculiar way, acting much more rapidly on the dense parte 
«>f the image than on the thin parts, so that the oontraste of 
. the image are greatly reducexl, with a consequent marked im- 
pnwement in the printing quality of negatives which for any 
Kiason are "hard " or too strong in contrast. A reducer pos- 
««sing such a valuable property as this naturally attracted 
mticli attention, (but it is noteworthy that statements of dif- 
ferent Observers concerning its action are more or less con- 
tradictory, and the conditions necessary for suocessful work- 
ing do not seem to have been fully grasped. It is not im- 
probable also that the persiulphates sold as "photographic" 
ohemicaJs have varied oonsideraMy in quality. Be that as it 
may, so experienced a photographer and chemLst as the editor 
of one of our leading photographic journals stated not long 
ago that he had practically given up the use of persulphates 
as reducers because of the uncertainty of the results. 

It is singular that there has been a tendency to attribute 
practical failures to some inherent difficulty iA the process, 
rather than to the probable presence of avoidable impurities 
m the p<Tsnlphate or in the photographic film. The fact that 
a white precipitate may appear in the liquid whilst reduc- 
tion IS going on was quickly recognised, and one of the most 
*>x:^enencetl practical photographers now living regarded this 
(at one time, at any rate) as a distinct advantage, ibecause it 
showed that the reaction was taking place ("B.J. Almanac," 
]f^' P;/'^2), and more recently it has .been proposed to base' a 
"time" method of reduction on this phenomenon (R B 
Hughes, "Phot. Monthly," 1909, p. 207). The appearance 
of this white precipitate certainly indicates that the reaction 
as proceeding, but also shows clearly that it is proceeding in 
the wrong way. If the reaction is going on properly, and pro- 
diuxng oidy silver sulphate and alkali sulphate, as it ouglit to 
do no precipitate should form at all. A clear gelatine film (ex- 
hi,bited by tlie lecturer) was originally an extremely dense 
overKle%'eloped negative, but the image was completely removed 
by ammonium persulphate without raiy precipitate or even 
cloudiness appearing in the liquid throughout the process. In 
fact, in the numerous experiments made in this series with 
the alkali persulphates, no trace of milkiness appeared except 
in one instance, when, throu.gh inadvertency the tap water 
(which contains rather more clilorides than is usual) had not 
been washed out of the film. It is easj- to prove that this 
milkiness or white precipitate consists of silver chloride or 
bromide, .dually the former, and its formation is doie to the 
presence of a soluble chloride or bromide in either the per- 
sulphate solution or in the film under treatment. The mis- 
chief is Uvat if silver chloride or bromide is being formed in 
the liquid It may be taken as certain that it is also being 
foi-med in the film to a greater or Jess extent according to cii^ 
cumstancas. It is possible, in fact, for the silver image to be 
largely converted into silver chloride if it is acted on by a 
solution which contains a chloride as well as the peraulphate 
because as soon as the silver is converi^ed into sulphate it is at 
once precipitated as silver chloride, moro or less completely 
am>rd,ng to the relative concentrations of the silver saJt and 
the soluble chloride. In fact, a mixtui* of a persulphate and 
a chloride has been proposed as a bleaching agent. 

[An exhibit showed this point clearly. A dense image, 
treated with persulphate containing a considerable proportion 
«rf xddoride, had been largely converted into sUver cliloride 



as the colour and general appearance showed. One end had 
been dipped in a fixing bath, which had removed a consider- 
able part of the image, whilst the other end had been dipped 
in a developer which had reconverted the chloride into metallic 
silver.] 

Experiments made with "strip" negatives show cOncluHively 

(a) That the alkali persulphates markedly reduce the eon- 
traste of a negative by dissolving the dense parts of the image 
at a far greater rate than the less den.se parts, in agreement 
with previous statements, and that the flattening of the Bcale 
of gradations is more marked the longer the persiulphate is 
allowed to act. In some of the specimens exhibited the higher 
densities, although distinctly different in the original nega- 
tives, had become not only much reduced, but practically in- 
distinguishable from one another. This is a necessary con- 
sequence of the fact that 

(b) The rate of action of the persulphate increases with the 
mass of silver present ; the higher densities are reduced more 
rapidly than tlie lower, until the whole image is reduioed to 
one uniform density. 

(f) That the rate of action of the peraulphates is increased 
by the presence of free acid. 

(f7) That the rate of action of the persulphate is incresised 
by tJie previous addition of a, sm-iil quantity of a soluble silver 
salt, preferably tlie sulphate.' 

(e) That if the persulphate is made alkaline by the addition of 
ammonia, the redoing action is not stopped, but is made mueh 
slower, as Namias stated (" Eder's Jahrb.," 1901, 166). 

The exact modo of action of the persulphate on the eil'ver 
deposit was made clear by the experiments of J. I. Pigg (" Brit. 
J Phot. Almanac," 1904, 894-99) and W. Scheffer ("B.J. 
Phot.," 1906, 964). Pigg made photomicrographs of a half-tone 
screen negative (wet plate) before and after treatment with per- 
sulphaite, and showed that whereas the ferricyanide end hypo 
reducer attacks the smaller grains and completely dissolves 
them before producing any marked effect on the larger granules 
in the middle of each " dot," the persulphate attacks the larger 
granules first and reduces all the granules to practically the 
same size before the smaller granules are dissolved or even 
appreciably reduced. 

Scheffer made photomicrographs of sections of an exposed 
and developed film, and found that with hypo and ferricyanide 
the silver in the uppermost layer of the film is completely 
dissolved before the deeper parts of the deposit are attacked to 
any great extent — i.e., the deposit representing the shadows is 
removed, whilst much of the deposit forming the higher lights 
is left. With persulphate, on the other hand, action takes 
place uniformly throughout the deposit, and is conditioned 
mainly by the size of the silver granules. The persulphate 
solution penetrates the film rapidly, but acts on the silver 
somewhat slowly. The hypo and ferricyanide mixture pene- 
trates the film slowly, but acts on the silver rapidly. 

Practice. — ^Ammonium or potassium persulphate can be 
obtained at a moderate price even at the present time, and of 
a very high degree of purity as regards freedom from haloid 
salts, if purchased from any of the principal dealers in fine 
chemicals. The ammonium persulphate is preferable to the 
potassium salt, because a solution of the latter stronger than 
2 in 100 cannot be prepared at the ordinary temperatures. It 
is not advisable to use the ammonium salt stronger than 5 in 
100, even in cold weather, and 2.5 in 100 is strong enough in 
warm weather ; or if the solution contains free acid, as it does 
after it has been prepared for 'a few days. The solution must 



2 Some workers »dd silver nitrate solution to the persulphate in order to 
acoeler.te the aet.on, but this is undesirable, becausa with this 8a t a preciDUata 
of silver perox.de is formed and a^n unneces^-arv complication i, introduced No 
ve?yc^o\d'';j''luf,.r'''i"^''"' "itli silver sulphate. aI a mat.er'of fact,"e/cept1S 
i^llll wZt ' ^P'"' '"'"'■ so'"""" of the persulphate acts as quiokly aa 
icidUth^w .t^""?'"*'?"' i^'e^'ly "ecessarya few drops of dilute sulphuric 
»cid IS the best thing to use if silTer sulphate is not at hand. ouit-uu™ 



Marah 8, 1918. J 



THE BRITISH JOUENAL OF PHOTOGRAPHY. 



113 



be made with cold water, and it is moat decirable that distilled 
wat«r, or at any rate water fre« ivujn chk>rid«s, should be used 
for this purpose. The solutions decompoM gradually, gaining 
free acid and losing persulphate, hut if kept cod and oat of 
9tr"ng light the rate o£ change is slow. The ammoniom salt 
diEiolTcs readily in water, and tliore is no nevd to make op a 
large 'volume of sohiticra at one time. 

The negatives or positives niust be tjKnwgkly fixed and 
waxhed ; if they have been dried theyjdiould be soaked in water 
for at least three or four hours in order to avoid uneven action. 
They should be washed in three or four change* of distilled 
water to remove any soluble chlorides; the volume of water 
nasd for each washing need not l)e large, but •'aoh quantity 
should be allowed to act, with fi'<->|uent rockin;;, ior not less 
than five minutes (longer is better) and the draining between 
successive washings should be thorough.' The film must be 
free from finger marks and greasy patches. It is most 
important that the plate or film shtmld not be handled with 
dirty fingers after it has been placed in the persulphate solu- 
tion. Some form of lifter should be used if possible ; if the 
fir.'ers most be used th>7 «h ' ' - ' i ' . • t«p (and 
D'. wiped on a towel) imiii' the plate. 

The worst failures I hsve >> - use of |»-r->iilphat« were 

due to handling the plate<t . rs that u> i- 'Supposed to 

be clean, but were not. If the precaations spcilied are duly 
•ob^rvpil. the reiliicfit.ii witli i)*-r<.iilit}ijtt« i« in ru^ experience. 



a safe and certain operation, the principal risk being that the 
reduction may go too far. In ordinary work the presence of 
soluble chlorides is the principal source of error. If for any 
reason the absence of chlorides cannot be ensured, the process 
should be carried out with a solution to which sufficient 
ammonia has been added to make it smell distinctly of that 
substance. The action will then be slow, but the character 
of the result will be the same and the risk of stains and irregu- 
larities much less. A few drops of ammonia may with 
advantage be added to the water used for the first two or three 
washings. 

[Specimens were shown illustrating the effect of the persul- 
phate on ordinary negatives. For instance, in the case of a 
whitewashed cottage with a grass lawn in front, considerable 
reduction can be effected in the sky, and the walls of the 
cottage, without any recognisable effect on the grass. In the 
case of a waterfall in a glen, the density of the water can be 
markedly reduced with only a slight effect on the much thinner 
deposits that represent the surrounding rocks-l 

Persulphate can also be used with good effect in the case of 
lantern slides that are too opaque in the shadows. For this 
work it is not advisable to use a solution stronger than 2 parts 
in 100, or approximately 8 gruna per oz. [Specimens of results 
were shown.] 

C. H. BoTBAnnn- 
(To he continued.) 



AXIAL ABERRATIONS OF LENSES. 



'We aie indebted to the Bureiin of 8fei' Im 1,'inlcd States Department of Commerce (or the following paper, which deals 

with the chief axial aberrations of lenses ^- '-* In <l«lail the pnetical method worked out by the Bureau, based upon that of 

Hartnuuin for the msararemsnt ao<l i>lo(ting of the abanrntioa*. In reptodueiiig the tsxt of the paper, ezigeneies of space have compelled 
lh« omission of oos section, oamsly , that daalins mathematieslly with the soaiess of error. A brief abstract of this section is inserted 
in th« text s« printad. in its appcoprtat* fUoe.— BM. " B.J."] 



{CcmtimM»d frcm pao4 108.) 

4 Zonal VASunoii or tkb Eqviv tunrr Focal Liuti;TH tE.F.L.) 
(.SisK i'<i!<omoN).— Aasnae a Jen* f.L, (Fig. 4) eiiUrrly rurrected 
for >(>h<Tual and ohiomatic aberratioiiA. Then all aonsa will have 
the ssme axial focal puint for all ' olours. If all the scoss have 
aot the natiMt fnsl length, then 'ii.- ..l.-Tatir.M , all.-H ooma is prMsnt. 

Let /'V (Fix 4) be A «ma .r to Ihs axis. 

Th-'i /%> ^ ' 1- ..... ...I :n / . «ine of the lens 



«r4^ 




IllaetnUoa laa«> by Un* tnt Itam ifherlssi •tomiloa, bm 
bsTiac Moml TarUMoD of ■. F. !>■ 



IL,. U tba IsiM 

tioDs. the point /' will b« tofM'-<i l>v 
•II othm zimm at /" ; but if th- K K 
of the diflafSiiC lones be different, t. 
mai^niSeatioa fnm ths osaint xoi' 
iica«rd in /" Q< by tb* csntr.' 
In other word*, the *d^ xor- 
piase, bat in ' 



is frss from »phcrical sod cbramatio aberra- 

tbs edge xooe a* well as by 

I., (equivalent .fooal lenflh) 

'1 have a differsat 

ct PQ will bs 

■ edge sons. 

I <^ in the 

age by the 



i9^uinA tor w«a1iui< « 



tetikM 



'•« aaiattTa In • i>ro- 
p«TMlpkSM •> »ll. 



central lone. If P be a finite point, then Q' will be a very 
(mall disc nf somewhat larger diameter than ibe diac pro- 
duced at Q'. Hence the point V *iU be imaged in a figure dhs^ied 
like a ooinet. Iiavin^ • bright point at one end and trailing off in 
a broad fosxy circle at the other. The sharp point will be directed 
toward or tmray from the axis depending on the relative sizes of the 
focal Isofltlis (or tJ>e edge and oentral lones. 

The grsphkal representation of sonal variation of E.F.L. is 
shown in Fig. 2. Prolong the rays to P,', P,' P,' and P,' back- 
ward into the lens Ull they meet the rays P,, Q,, P„ Q„ P„ Q„ 
and P,. Q, prolonged at A',, A'„ A'„ and A', (K , is obtained by 
mmpotti^ the axial focal length and measuring back (rom P,'). 
The points AT,, A'„ A',, and A", are the principal points (or the cor- 

r.- ''—; zonee, and the snr(ace on whidi all these points lie is 

I .il surface o( the lens. 

lA^ n om Iht height at which the incident ray strikes the lens 
and ■ be the aogU which the re(racted ray makes with the axis. 

Than k 

^ E is defined as the E.PX. of the sone at a distance '( 

H 



axis. 
In Fig- 2. 



sia Hi 

_*¥_ 
sin ut 



= iTiPi' 
- IffPs' 



sin Udi 

.''* - K,P,' 
aiau* 

will be the equivalent focnl lengths of the corresponding zone« 

If the lens is absolutely free from spherical aberration, then tin 

oonditiea 

h 



sintt 



» constant . 



(a» 



THE BRITISH JOURNAL OF PHOTOGRAPHY, 



[Mardi 8, 1918. 



nieuM bIbo freedom from zouai variation of. the £.F.L. ; hence 
freedom from coma for pointe ncaa- the axis. Equation (a) is oom- 
inonly known ae the "Sine condition" for rays from an infinitely 
distant object. For artificially stopped systems and at large angles 
with the axis ot/her additional terms have to be considered.' 

In practice no lens is entirely corrected for spherical aberration. 
Some of the latter is left in to balance the higher order aberrations 
and to compromise for the beet condition for the elimination of 
the other errors. In tJiis case, ae is shown below, the condition 
for freedom from coma is 



/ = 



•(*) 



where / for the zone h is the distance from the axial principal 
point A',, to the intersection of the ray from that zone with the 
axis. In Fig. 2 — 

/■ = A'lPi' 

/j = A'lP/ 

/a — KiPn 

ft = KiPi" 
Let L L, (Fig. 5) be a lens with spherical aberration present. 





^ 


L 


,tx: 


1 


m 


■ 








/A 


^-^ 




/ yi 






/m 


mf 




P // 














/^>1 




// P"P 


n p' 




^^ 


/ < 


» 


c 


f^— ^ 


:^ 











Fig. 5.— Diagram illuBlratiag image by lena possesiing spherical aberration, 

but free from zonal variations of E.F.Ij. (Condition — - = «onst. fulfilled.) 

sin u 

Then tlhe rays from the edge and centre will intersect the axis at 
l'! and P° respectively. Assuming 

— — = constant, 
sm u 

every zone will liave the same magnifying power, and there will 

bo a series of images of the object P Q ait all points from P' to P", 

all of the same size. But the position of the plate will be the 

position of the average image somewhere between P' and P', say. 




/•=<,") fulfilled. 



disc at m". At (J" there will be a, sharp image produced by some- 
zone between the centre and the edge of the lens. Following the 
same procedure, tlie otlier zones will produce discs of diameter 
smaller than mm'. The figure on G G will consist of a bright point 
at m", trailing oB into the broad fuzzy perimeter cd the disc mvi', 
giving the true shape of coma. 

In order to obtain a symmetrical image in a lens with spherical 
aberration present, the series of out-of-focus images an any posi- 
tion G G (Fig. 6), formed by producing the rays oi ihe various- 
images Q' to Q", ra-ust all be symmetrically placed with respect to- 
the ray K Q', through the central zone. In Fig. 6, 









K P" 


P" Q" 










K P' 


P' q' 






' • 




h 






but 


P" 
P' 


Q' 


sin«„ 

sin Ml 


E' 




and 




KP 


' = F... 


KP" = 


fn 


where the 


subscript ' 


' ax 


" refers 


to the 


axiaJ zone. 


Hence, 








E„ 





For the axial zone, 



Ea: 



Fig. 6.— Diagram iUustraling image by lens with condition (^Ji. 

Vhin 

GG. The image at P'Q' for the edge zone, when produced forward 
to the plate G G, will become a largo disc in the position wim>. The 
i mage f oj^ the^ntral zone produced back to G G will be a small 

certafn ,?in1T»/^ti' ''"■•"'* deftniU^ is due to these seven ei7or8, but there are 

iwent.^rmJ^f ,hl ^^'*".V C/apski kitcs twelv. terms of the fifth order and 
twenty terms of the seventh order, besides the five terms of the third order. 



/., = A'l Pi'. 

Hence £„ — /n = is the condition for a symmetrical imago free^- 
from comaltic flare in a lens with spherical aberration present. 

If we plot along the axis P' Y (Fig. 2) the height h, and along 
P' P the variation A£! in the equivalent focal lengths of the zones- 
from Uhat of the central zone, we obtain the curve P' S' repre- 
senting the zonal variation of the E. F. L. If we represent Uie 
E. F. L. of the zone h by Eh and that of the axial zone by .E»„ then,- 

similarly, if /„x is the distance from the paraxial principal point 
to the paraxial focal point and /u is the distance from the same- 
principal point to the focal point for the zone h, then the sphericaL 
aberration aV = fh — /ax. 

When expressed in terms of the aberrittions A E and a V, the; 
condition £i, — fh becomes 

£„ _ 4 = (A',, + AE) — {f,.+ A 7) = aE— aV, 

sine* JJox = /ax. . A It 

In Fig. 2 the full line represents AV and the dotted one is AA,- 
hence the condition for freedom from coma for points near tho- 
axis, AE — AV = 0, means that the two curves coincide. 

Variation of Sine Condition with Colour.— 11 the zonal variatioii. 
of the E. F. L. be determmed for different wave lengths, the curve* 
may not coincide, showing a variation of AE with the colour. 
Since the size of the image dei>ends on the E. F. L., tlie zonal 
variation of the E. F. L. with colour gives the variation of the size 
of the image with the colour, and hence the oblique chromatic- 
aberration. 

5. CuBVATUKE or FiELii. — The preceding aberrations are ihe ones- 
to be given most consideration when examining the central defini- 
tion of a lens. When we depart somewhat from the centre of tlie 
field and go toward the edge, we find that the image of a plane 
object does not lie in a plane. If we plot the points of best focus, 
we find them forming a surface of a saucer-like shape. This defect 
is known as curvature of field. 

6. Astigmatism. — Toward thj edge of the field ws find that there 
may not be a position of good fo^s. The image may consist of a 
series of streaks running radially, and somewhere in a plane other 
than that of the radial image another series of streaks in a direction 
perpendicular to the first. This is due to the fact that a pencil of 
rays from a point striking the lens in one plane focusses at a point 
different from the focus of a pencil of rays from the same point, but 
in a plane perpendicular to that of the first pencil. This error is 
known as astigmatism, and is non-existent in the centre of the field 
of a, lens with good surfacing and not strained in the mounting. 

7. DiSTOETiON. — Another aberration which affects the image 
toward the edge of the field is distortion. This is the deformation 
of a straight line in the object into a curved line in the image, due 
to a variation of the angular magnifying power of a. lens for ray* 
incident at different angles. 



MoK^ 8. IdlS.] 



THE BRITISH JOURNAL OF PHOIXJGRAPHY. 



115 



Besides tke preceding abernttiass. we mast take into account the 
M-called hybrid aberrations, or the effect of some of the previously 
mentioned erron on the others. These affect the definition at the 
edge of the 6eld, and are exceedingly important in photographic 
leas systems where a large field is very desirable. 

For the purpose of ascertaining the best nae to which a lens of 
s given description may be pat it is neoesaary to determine the 
magnitude of these aberrations, and the region of best correction. 
The signiBcance of the axial aberrations from the point of view of 
{general definition has been di*cui<sed in a previous paragraph. 
Hence the determination of these axial aberrations will give Qs a 
lotnparativs value of the lens. To do this the method described 
below was devised. 

Method. 

The method used is an extension «f Hartmann's method of objec- 
tive testing*. His work is fully described in the " Zeitschrift fur 
InstroKentenkimde." Hartmaim oses a screen to isolate rays along 
four diameters, 45^ apart. He takes ahadowgra(^ at points very 
near the fooos, and frtan these he obtains tbe spherical aberration 
iiod the astigmatism along the axis. For the zonal variation of the 
l-l F. L. he places the lens with tlir mount in contact with a scale 
siht meaaorea the apparent length of Uie fcale divisiooa throogh the 
lens with a micrometer. Hartmann's method has been applied to 
many large telescope objectives and small lenses. The method is 
tedioos and eoopUcsted and requires two totally independent seta 
nf measorsmeats to obtain both the spherical aberration and the 
jcimal variation of the £. F. L. Moreover, (or comparatively thick 
tenses it is not possiUe to ose the method ior the aooal variation 
uf the E F. L. The extension described later gives both the errors 
with a single m eae w nent, and can be nsad for all kinds of lenaas 
uf relativdy large apertore and short focal length and for complete 
teleaoopic s y s t a m a. 

1. Dtacannoii.— Fig. 7 is a diagrammalie sketch «t the meihod. 
Parallel says from a distant source fall on m metal screen S S pierced 

S . B 




l-ic. T.^IiwamaHBatle Sketch ol Methods. 
with atMll holea which iaoiats mngle tST*. These rays are then 



efracted by the lens system mder t««t, I, L, and come lo a focus at 
r. or near F, in the prssence of spherical aberration. A pboto- 

Krai>hic plate ia placed in the posit in A and a shadow photograph 
tsken. The plate is then moved Ut t!ie position B on the other side 
of the focus and another shadow photograph taken. The shadow 
1'hotogvaphs have centre diflrsctlon <lisos which can readily be 
in. uiored if ears it taken to ch»«»e a screen with holee of proper 
•iiAinetrr and distance apart. It the plaU is near the focus, as at 
n. eharp discs are obtained ; at A, farther away from the focus, the 
discs are leas sharp. 

Considsr a my, R (fig. 7), passii^ IhtDV^ the screen and 
striking the leiM at a height, A, tmm the centre. It is refracte<l 
by the IfiH tjfal^ making a disc on the plate A at m, and on the 
plate i7 at a. If J^ and y are the |>oeitioaB of the discs made by 
the ray tiirongh the centre of the lens, then » and 6 will be the 
< distanoee from the centre of the plates il and fi to the intersec- 

I tions of the ray A' with the plates^ The position F will (>e given 



by the erpresaioo V 
Hie ft»d fofatt V 



<id 
a + 6 



« 



of the plates. Assuming that Vo is the distance of the paraxial 
focal porint from M, t.hen the splherical aberratiofi for the zone at a 
distance, h, from the lens axis is A Vh = Th — Vo. 

In Fig. 7 u is tlie indinatdon of the refracted ray wtUi the axis 
and 

a + b 



where V is the distance UP from 



sT: 



tanu = 



d 



from which sin u is easily determined. Hence, — — for each ssone- 

sin i< 
can at onco be determined if A ia known, for Mm porpoae the 
screen used was calibrated and the position of the holea was known 
to within 0.005 mm. 

E. D. TiLLTBH. 

H. I. Shtltz. 
(To he continued.'^ 



ilssistants' RoteSe 

— • — 

Nottt by auutantt luitabU for thia column will bt —niidTtd 
mud -pmd for on the first of the month following publitalitn. 

The Influence of Good Negativea. 

It is generally understood that the quality of a print depend* 
apon the materials used in its prodiKAion and tJie worknianehip 
employed, but before tank development and bromide paper were so 
popular itie quality of tlie negaitivo was coneidered of primary 
importance. 

The easing of plate deveicpment by the introduction of the tank 
and the versatility of bromide and other development papers have 
brongfat about a tendency to consider negortive making as of lass 
importaooe tiian it used to be. Oompared with old methods it is 
rary easy to tank a batch of Remfcrandts, or a botch of white back- 
grounds, or a batch of oopiaa wiUi the confidence of producing 
twelve decent negatives out of every dosen without any very special 
care, bat, alas ! it is just a trifle easier to let the three varieties gei 
mtTed, to moke up the solution witfaoot regard for accurate strength, 
and to jialge the tempeiaiare with a finger cr not at all. If the 
conaeqaent negativea are dense or thin, harsh or flat, there is a fatal 
(amptntion to reoMmber that bromide paper will cover the fault. 
A oompeteot bromide prints can certainly make pasaable prints oft 
ahnosi any negative, but at the same time aiyapprentice can make 
batter prints from a -ptrftet negative, than the cleverest man can 
from an impoasible one, and in much less time. 

Some years ago I was asked to undertake the development of a 
targe qoaotity of exposed plates, most of them lar^e-eized life 
etddies, some direct sod some copied. It was impressed on me that 
tha imiatilin nmst bo fool proof. \'ery large numbers of bromide 
printa w«r» to be made from them by jimior labotir, in the diape of 
girl aaskt4uits who oonld " print " in the barest sense of the word 
coly. A qiuotity of the pictures wsre of the white background 
variety, and I wim toki tlwt no negative waa to need vignetting, 
dodgii^, over- or under-exposing to give a good print, and that 
they were to be of a density which would iK>t necessitate extreme 
expoaares or changing of lan^w. 

The production of those negatives entailed some care, but I am 
oodvinced that the truufale was not waated, for had they been done 
in a slipshod manner an expert would have been necessary to print 
them and a greater amount of waate would have been incurred, for 
(aiMl thia is the point of the argument) though the right man caa 
,^^^«id prints from all sorts of negatives, he cannot do it with- 
dKWTimaaat of " mwsing about " that mdy come expensive in the 
sod. This covering np of poor negatives not only causes needless 
wests, it has its bad effect on tlie printer. The forced prodigality 
with paper, devdoper, and light iivdnoes extravagance in the moat 
economical workers, while the thought that his careful work is 
encouraging the scamping of the plate devekxpment is likely to turn 
a o ms cienUons printer into a " don't cara." 

l>n the other hand, peHect negativea enoooiage good work and 
ecjnomy, for with Uiem it is not necessary to spend time dodging 
and faking or to use paper in numerous tests or to oxidise pinta 
of developer in " forcing." There is, of couree, a qneatJon as to 
what constitutes a perfect negative, and it ia only Ukoly that 
opinions difler on the point, bat from a printing point ol view a 



116 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[March 8, 1918. 



periect negative is the kind »1 negiitive iiial can be found among the 
okl boxes of almost any Hrsl or middle class iVnn, a negative that 
can be printed in platinum- or P.O. P., and at the same time will 
give a good ^irint on any good make of bromide. This latter ia an 
impoirtant [xiint, for many poor negatives will print on some par- 
ticular brand of paper ea«ly, o^ving to a peculiarity of the paper. 
The perfect printing negative doe.^ not require any special make or 
•ny special genius to give a good print, and such a negative can 
be produced witliout any special talent or trouble if the important 
details of tank development are not neglected. I am, of course, 
taking it for granted that tile subject and the bnrhground are cor- 
rectly lighted, for. if not. that omission aloiie may spoil the negative 
for the printer. — Tiifrmit. 



€xDibitions 



TMPKRIAL WAR PHOTOGRAPHS IX COLOUR. 
A MOST ontereating and important exhibition of official war photo- 
graphs was opened at the Grafton Galleries on Monday, March 4. 
the exhibits being noteworthy for the fact that they are nearly all 
tinted in colour, while all are very large scale enlargements. Tlie 
big scale and the colour combine to make this the most realistic 
collection of war pictures that we have seen. The figures in some 
cases are not far short of life-size, and the spectator is brought into 
such close proximity with the subjects that, without much effort, he 
can feel himself to be part of the scene. The process used seems to 
be sepia toning, followed by the aerograph, and the user of the aero- 
graph, whoever he may be, is much to be congratulated on the skill 
with which he has used it, and the knowledge of colour he has dis- 
played. In many instances, also, the photographer has shown a 
most happy choice of view point, and remarkable ability in 
" pressing the button " at exactly the right moment. As regards 
scale, the most notable achievement is the photograph catalogued as 
No. 2, and entitled " Dreadnoughts of the Battlefield." Naturally 
this refers to tanks, which, skilfully camouflaged, are seen crawling 
up to the attack in one of the recent advances. This picture 
measures 22 ft. by 13 ft. 6 in., and, we understand, was enlarged 
from a 5 X 4 negative. This means an e:ilargement of at least 53 
diameters. Another picture (54), " W^^''^ '* ^^^ Pessimist? " repre- 
sents a great effort on the part of the enlarger. This is a very long 
frieze panel picture of a line of troops on the march, and is described 
aiptly as "The great puzzle pictuie, to which the spectator cannot 
find a solution." Space will not allow us to make special reference 
to more than a few of the 150 pictures on view, which cover nearly 
every phase, of life on active service, and, also various battlefields in 
France, Palestine, and Mesopotamia. Some of the Eastern pictures 
are of remarkable interest, notably "General Allenby Entering 
Jerusalem " (30), " The Reading of the Proclamation at Jerusalem " 
(83), " The Entry into Bagdad " (81). These are, or will be, of 
historic value, but there are others also worth special attention as 
pictures, notably, "The Long, Long Trail" (74), showing a march 
through the desert, through visible flying dust and sand, and obvious 
intense heat. Another impressive picture, " They also Died for 
England " (75), f;hows a long line of dead animals in the desert, 
marking a line of march. A great scene of energy and movement 
is depicted in " In the Wake of the Retreating Turk " (32), where 
our men are seen dragging an enormous gun through the narrow, 
winding streets of Bagdad. Among the general subjects, a fine 
6gure study is "After the Scrap" (42), where a finely-set-up 
" Tommy " is seen returning from the fighting line with what 
Mulvaney called " the fog of fighting " still on him, a well-pleased, 
rather damaged conqueror, in a highly dangerous mood for any Hun 
who may yet get in his way. The damage of war is illustrated in 
startling fashion in " All that Remains of the Beautiful Chateau of 
Caulincourt " (41). This is nothing but an incredible hea<p of small 
fragments of rubbish. A very happy example of successful photo- 
graphy and colouring is " Come on in, the Water's Fine " (45). 
Naturally, this is a bathing scene, but in it the combined efforts of 
all responsible have produced a most excellent result. The subjects 
are so numerous that there is interest for everyone. From a German 
trench through which the British have just gone with their bayonets 
we can pass to a view of Tommy showing a small French girl a 



jihotograph of his own little girl at home. We can view close at 
hand many notable 7)eople who have visited the Front. We can 
study Tommy, from the mood in which he acts "Cinderella" to 
that in which he meets the Bosche. We even meet with the some- 
what unexpected vision of a Zulu chief in full native undress, in 
conversation with Staff officers, somewhere in France I The subjects 
are, in fact, almost as numerous as the pictures, and the exhibition 
i.s one that should on no account be missed. Certainly not by photo- 
graphers, who will see many things that make them feel proud of 
their craft, and still prouder of their fellows who have pi-oduced 
such fine results, under, in many cases, most extraordinarily trying 
conditions. All profits on the exhibition will be devoted to war 
charities, and the pictures will, no doubt, tour the counti'v at a 
later date. America is one place for which they are destined, while 
similar series will be sent to France. We understand that the photo- 
graphers responsible for these ])hotogr,aphs are Lieutenants Brooks 
and Brook, of the British Army, while the organisation of the 
exhibition was put in the hands of the Canadian War Records Officei 
which was responsible for the two previous Cniiadiaii exhibitions held 
in the same galleries. 

^ 

FORTHCOMING EXHIBITIONS. 

March 12 to 15. — Hackney Photographic Society. Sec, Walter 

Selfe, 24, Pembury Road, Clapton, E.5. 
April 18 to May.-— Hampsfliire House, Hammersmith, Photographic 

Socioty. Entries close March 19. Sees., H. T. Callender, 10, 

Aore Lane, Brixton, S.W.2; or W. T. W. SJiiers, 201, Goldhawk 

Road, London, W.12 



W. 



meetings ^T Societies. 



MEETINGS OP SOCIETIES FOR NEXT WEEK. 

SiTDBOAY, MAKCH 9. 

Stalfbridge Photographic and Scientiflo Society. " Trimming and Mounting." 

Harwood. 

Monday, Maboh 11. 
Dewsbnry Photog rapliic Society. " Hints and Dodges." N. Ruddlesdcn. 
Keighley and District Photographic .Association. '^ Gum-Bichromate Process." 

J. H. LeightOB. 
Bradford Photographic Society. In Cromwell's Land." F. Thorue- 

TCESDAT, March 12. 

Royal Photographic Society. "A Convenient Aocnrate Photometer for the 

Measurement of Photographic Densities." D. E. Benson, W.B.Ferguson, 

and F. F. Renwiok. 
Birmingham Photographic Society. "The Wonderland of the Wasps." J. J. 

Ward. F.E.S. 
Hanley Photographic Society, Y.M.C. A. Members' Night. J. R. Cox. 
Stalybridge Photographic and Scientific Society. " Colour Photography " 

(Paget Process). R. H. Beavan. 
Manchester .\mateur Photographic Society. Social Evening. 

Wednesday, Makch 13. 

Photo-Micrographio Society. " Some Disease-Producing Proto^toa." Professor 

R. T. Hewlett. 
Bristol Photographic Cl»b. Members' Lantern Slide Evening. 
Ilford Photographic Society. " All Home Made" N. K. Jackson, 

TiiDRSDAY, March 14. 

Hull Photographic Society. " Amateur Photographer." Prize Slides. 
StockDort Photographic Society. " Lantern Slide Making and Toning Bromides." 

J." J. Rothwell. 
Liverpool Amateur Photographic Association. " Child Life in Japan." Dr. W. M. 

Cairns. 
Hammersmith (Hampshire House) Photographic Society. *' Among the Foothills 

of the Eastern Alps." J. D. Johnston. 
Rodley and District Photographic Society. Y.P.U. Portfolio. 



ROYAL PHOTOGRAPHIC SOCIETY. 

Mketing held Tuesday, Mardi 5, the vice-president, Mr. F. F. 
Renwick, in the chair. 

Captain G. E. Allen, of the Royal Flying Corps, delivered a 
lecture on "Cairo," illustrated by a large number of lantern slides 
showing the e.vterior and interior of innumerable mosques. Ha took 
his audience through the narrow streets of Cairo, with its gates, 
arches, and minarets, out to the Pyramids. He concluded with 
some views of Alexandria, showing it to be very much like a modern 
Italian town. 

On the proposition of the chairman, a hearty vote of thanks was 
accorded to the lecturer. 



&Urd> 8. 1918. 7 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



CROYDON CAilERA OLUB. 
Mju F. Aolrotd gave a lantorn-lecture on " TraveUen' SamfJei, 
gathered with motor and camera," which covered a wide ground, 
with carnal tfaemea gatiiei«d by the roadaide. Tljat they had no 
oonncciing link did not detract from the interert of the lectiire, for 
ha ia a eloae observer with a cathohc knowledge which enablea faim 
to deal with varied topia in instruotive and dryly humorona fashion. 
Nearly all the viewa inchided hi* motor car, a fact which often 
■aoured aoceptaooe of printa by jonmnU devoted to motoring, though 
the subjects depicted had not the rcaioteat connection with it. tvi- 
denlly iili. Ackroyd is poaseaMd of the joomaliaiia instinot. 

Prior to the lecture be occupied ai> unchallenged position in the 
clnb as th« maker of Iantarn.«iides, M-hich, teohmoaUy, might be de- 
ncribed as trinmf>haaUy eiMonUa, and far from assertive in a 
pictorial ai^>eot. Now he sfipeu* to be in a transition stage, for 
■uuiy of the slides shown were really good, some fair, and the rest 
ramuMcent of the past. In the discoaaon Mr. Salt was anxious 
to leara how iIm special " miUowed » hitenrasli " effeota were saoored. 

Mr. Ackroyd did not throw much liirht on the myat^n,-. but said he 
quite underMood the want of appr«<< ation eip rc e a e d , for fai> main 
ciiject waa to appeal to the brain and not to the eye. The praaidtnt 
<91r. A. F. (kitiaiiae). in profXMing a \xt* d thanka for an asesUMt 
•nd entertaining^ avsoing, said be fe:t sure if any we<re to see N^tlw 
for the first tint* throog^ the medium of Mr. Ackroyd's normal 
lantern .a Udes. they not onljr would be willing to die. but actually 
deatroua of expuinj, in coofcrnation at the wall-known adage. He 
pramleDt ia the last ooe to gush, so no doobt ooold arias aa to the 
sincerity of tb« OMDplioMat, which waa faaKngly acknowMged by 
the lecturer. 

ThroQghoot the tvening the lantern ilJMBinapt an open arc ran 
on alternating cnrreot— Miaved like a soda-water syphon in distrcM, 
varied with the "in and out " buatoma. The old stock of oaitiona 
waa a ih a oated , and new onas were given thair firvt trial. At all 
timea an open aro on atteriMtiiig supply is a bit of a beaat, and with 
frolieaome caifwns toma into a varitabie Bm. CatUinly oar old 
friend the limaligfai has aoch to raooaunsod it. and WMijr thiidt for 
Tcojeetioa on a a iod ar Me aeale it haa nevar ba«o beaten for ashibiting 
•ilidea to the best advantage. Later on the half-watt nMUHic fllsnient 
lamp wiU compete for favour. 

Tmi Sorra Lomoom pBorooBAmc Socnrr.— At the fnrtnightly 
■aseting of this society, on Monday evening, March 4, a paper of 
roDsiderabIs interest to profeiaional photographers waa rvad bv 
Mr. Dnnkwater Aitt.- F.R.P.8., on the rabject of "The Phoui- 
liio and Prrmitrs." The lecturer made some prelimi- 
- -jrks on the necessity for photographers, in common with 
other proferaional and cmnmercial men, ooauneacing now to pre- 
pare for " after t^i- » •■•• " condition- '■•• i— rroving their premises 
LS far aa possil> if everyt!; r power to faciliUte 

the conduct of u.. i.vnn, not •■ .. *iUi greater «<-onoray and 

' fflciency, but also with increased atUntion to the artintic quality 
' f the surroundings willi which *urh Imainasses ahoaid be, bat too 
ftcn are not, associated. .Mr. Butt t!i<-n proceeded to eaasi<ier the 
•iesign and decoration of p!iotn(rri«r>)''' premises generally. 

A beginning was made with t)i>- -fiop window, that betng the 
photographer's 6nt and most important mssni of bringing hf* work 
to the notice of possible clients. The advaotagaa of the amall 
window, as being eaaier of ant 1 • more econotnical of speci- 

mens, and Bors'coadncive to t( - display, were discunsed. 

The varioas methoda of the draign nn4 decoration of the windows 
thamselvss were then gone into, and a number of slides of some 
• tU'ing windows, including those deeiicned by Mr George Walton 
f - he Regent Strvet branch of the Kodak Company, and otben 
(•■iiigned by Mr. Bott himaelf for Mr. Keith Dannatt at Woking, 
''Ir. Swaioe at Bowthssa, ate., wrre shnwn. 

In dealing with the arrangement, decoration and furnishing o< 
' ho reception room, the leetorer showed an original design for an 
ipartment of this kind. 

Paaaing next to the (ubject of the studio, a short historical sketch 

A as giveo of this, the most important development of the photo- 

raphar'a pr i sBlsia. This was illustratod by slides of a diaginm- 

-" of tb*- stodioa of MnnckbOTSB, 8tuart Wortley, 

>m*, R«jlander, and Valentine Blanehard, with dewrip- 

' <us of each. Pointa relating to the daaign of modem studios, 



117 



such as aspect, area, orientation, length, width, height, etc., were 
coufidered, followed by discussion bf the merits of the various 
forms of section, including the lean-to, ridge form, and single slant 
studioe, with reference to the lightings, etc., to be obtained therein. 
The lecturer concluded with the exhibition of slides and the 
gi\inf; of a full description of an ideal set of photographic premises 
suitable for erection on a town site and for the carrying on of a 
general high-class photographic business. The usual votes of 
thanks were tendered to Mr. Butt for a lecture which was evidently 
listened to with much appreciation and interest. 



Commercial S Cefla l Inteillsenct 

At the London Ba.nhruptct Court, on Thursday in last week, 
before ilr. W. P. Bowyer, oaScial receiver, the first meeting nf 
creditors was held under the failure of Henry .\rthur Yoerg Hoath- 
cote, photoin^pher. 22, St. James Street, Piccadilly, W. The 
debtor had recently held a eommisaion in the R.N.V.R., but was 
invahded out in 1915. He then raised £2,000 on a reversionary 
interest, and commenced bnainess as a photographer at 22, St. Jajncs 
Street. The initial expenses of starting the business were very 
heavy, and subsequently he found himself short of capital. In 
August Ust^he incorred a heavy loss, whereupon he closed the busi- 
ness, and haa since been without occupation. His liabilities were 
between £500 and £700, and his principal asset was his rever- 
sionary interest, which was charged, but should produce more than 
sufficient to pay his creditors in full. He did not adroit insolvency. 

It was decided to appoint Mr. Henry Fraser, of 2, Guildhall 
Chamben, E.C., as trustee of the estate, to act under the super- 
vision of a committee of inspection. 



news and Rotes* 



PuoTOMcnoaRAPBic Socirrr.— The next ordinary meeting of the 
Photomicrographic Society will be held on Wednesday, March 13, 
at 7 pjn., at King's College Bacteriological Laboratories, 62, 
Uuuxloa StreM, CJiaring Croas, W.C, when Pro^swir R. T. HewleU 
Witt lecture on "Some Pise a es pro ducing Promoa." Visitors are 
int-ited, and canls of invitation may be obtained of the hon. socre- 
Ur>-, Mr. J. r:. BrndlMini-, 1, Hogarth HUl, Fincbley Road, 
Heodon, SWA. 

BarrMH-MATic Panrrss Ekoravers* GLtnr— On account of the 
srareity an<i '>f .\merican fish glue, endtavoun have been 

made-to pr<'\ 'i.ent British substitute. Messrs. Penrose are 

now offering lo the trade their " Ghanticleer " process glue as a 
thorinifchly reliable article, and equal to the American product. 
Another point in its favour is that whilst American glue has always 
been put up in American pinte and quarts, the "Chanticleer" 
pfoceas glue is put up in standard British pints aad quarts, yielding 
one-fifth larger quantity. Leaflets of instruction for use will be 
sent on applirati'm to Messrs. A. W. Penrose and Co., Limited, 100, 
Farringdon Ruad, London, E.C. 

Tat IxDrsTXtu. Rn-oNSTRCcriON Cocncil. — The Industrial 
Reconstruction Council is holding a meeting at the Town Hall. 
Manchester, on Wednesday, March 13, at 3 p.m., under the auspices 
ird Mayor. Mr. O. H. Roberts, Minister of Labour, and 
lam .McCormick, Department of Scientific and Industrial 
Research, will be the lemling speakers. This is the first of a series 
of public towns meetini;.'* in all the great industrial centres of the 
country, arranged by the Industrial Reconstruction Council with 
the oiiject of awakening national interest in the vital industrial 
problems of the immediate future. Applications for tickets should 
be made to the eecretory, the Industrial Roconstniotion Council, 
8, Bouverie .Strn-t, London, E.C.4. 

Bhitisii IsiirsTRits Fair, }fi\&. — ^The fourth British Industries 
Fair, organised by the Board of Trade since the outbreak of war, 
will be opened in the Peiiniii(;ton Street premises of the London Doi^ 
on .Monday next. The building in which the fair will be held this 
year is situated within twelve minutes walk of Mark Lane Station 
on the Underground Railway, and a service of motor omnibuses will 



oft^Jtfir 



118 



THE BRniSH JOURNAL OF PHOTOGRAPHY. 



[March 8, 1918. 



pl,v between Mark Lone Station and the fair. In order to avoid 
any possible interference with tlie production of military require- 
ments, the fair ha« again been confined to the following industries — 
viz., pottery, glass, stationery, paper, printing, fancy goods, and 
toys. Admis!<ion to the fair is again confined to botid fide trade 
buyers, and invitations have been issued by the Board of Trade 
direct to o\er 60,000 firms in this country. Any firms which have 
not yet received an invitation, and desire to visit the fair, should 
»]>ply for a card of admission to the Director, Biiiisli Iiulustries Fair, 
Board of Trade, 10, Baainghall Street, E.C.2. 

PHOTOGHAPinc Record and Survey ok Nohi.suham. — Further 
interesting photographs and illustrations have been presented to the 
Public Libraries to assist in the scheme of formation of a local pic- 
torial reco:Ttl and survey, for which purpose gifts of photographs are 
beiuif invited. Mr. H. Gill, F.S..\., has given 36 local photograplis, 
including a series of illustrations of churches in the county, old 
houses, and objects of local interest, impressions of church brasses, 
etc. Photographs of Collin's Almshouses, Colwick Hall, and Linby 
Cross are among the prints given. A series of local architectural 
drawings, presented by Mr. Gill, are useful additions to the collec- 
tion. Other contributors include Mr. F. W. Dobson, who has given 
a print of Old Brewhouse Yard from the negative in his possession ; 
and .Mr. James Ward has presented a photograph of old St. Peter's 
Gate, showing the old horse trams. Mr. A. Lineker, of Bromley 
House, has given a set of photographs, including the Market Place, 
the Mayoral opening of Bulwell Hall Park, Southwell, Bro.xtowe 
Hall, and the Midland Railway Station in course of erection. 
Various other photographs have beeTi promised. Some of the photo- 
graphs are on view in the Reference Library. 

.Midland Railway Institute Photoohaphic Society, Derby. — In 
presenting his report at the annual general meeting held on Jlonday, 
.Mai\Ji 4, tile secretary said it was advisalble to corstinue to liave 
technical lectures from time to time, so that young or inex- 
j)©rieiM»d members may have an opportunity of stating their diffi- 
culties and of benefiting by tlie experience of experts in various 
!)ranclies of the art. The next generation is gi-owiitg up all the time 
and the fascinating hobby of photography, with the appeal to the 
artistic faculties for some, its alhiring ramifications into chemistry and 
physdcs for others, and its usefuhiees for stimulaiting social 
intercoui\se, naturally and inevitably attracts every year its new 
quota of neophytes and devotees, who require "helping and 
encouraging. The society occupies a strong po.sition even amidst 
the difficulties of this prolonged war-time. The weH-equipjied dark 
room has been in regular use, by one member or another, througlh- 
out the year. Old memiber*ip has been failly maintained, and 
fourteen new members have been enrolled since the last annual 
meeting. Tlicre are 120 subscription members, and, in addition, 
ahout fiiflty honorary members who are away on war work of one 
kind or another. IMr. William Smithard, who has h^d the position 
of hon. secretary since the society was formed seven years ago, is 
retiring, and Mr. C. G. Thorpe, of ithe Advertising Office, Midland 
Railway, has accepted the committee's invitation to take over the 
hon. fiecretaryship in successdon to Mr. Smithard. 

Tribunal AppEAL.-At Uie Oxford Appeal Tribunal the National 
Service repi-esentative asked for the withdrawal of the certificate 
granted to Arthur P. Maimers (38). married, Bl, 247 Iffley Road 
chemical and photographic dealer's manager. He was granted tem- 
porary exemption for three months by the Oxford Local Tribunal on 
January 31, the convmcing reasons that influenced them heing that 
Mr. Manners' employer, although above military age, had volun- 
tarily enlisted in order to undertake photographic work of a special 
character required by the mihtary authorities, and was stiil in the 
Army performing this work. Mr. Manners was left in charge of 
Mr. Rose's business at Oxford, and was himself doing valuable work 
for the militaiy hospitals. 

Mr Andrew Walsh appeared for Mr. Will R. Rose, who said he 
traded at Chester and Oxford. Mr. Manners was the manager of 
the Oxford buainess, which waa opened ten years ago. He was the 
only man employed in the Oxford business. There were thirty-one 
girls and two boys. The whole business was under the entire super- 
vision of Mr. Manners, and required a considerable knowledge of 
chemistry. There was no one in the place who could supply his 
place. His brother was the only man in the Chester business, and | 



there were upwards of 100 girk. He (Mr. Rose) was 46 years of 
age, and joined the Royal Flying Corps early in 1915, by requeet, 
to help with the aerial photography. He Berved one year with tiie 
Flying Corps rfnd then transferred to the Navy. He was the Officer 
Commanding a photographic aerodrome on the East Coast ; person- 
ally he was frequently flying, and was doing very important work. 
If he were not in the Navy Mr. Manners could be released. Mr. 
Manners did all the special medical work. 

By Captain Sheild : The business, he admitted, was not of national 
importance, but it was essential to him. 

Yom- application is on the ground of serious hardship to yourself ? 
— Just that. 

Which is no ground for exemption. Perhaps you don't know 
that?— No. 

What is there to prevent a woman being taken on to do the 
mixing of chemicale? — None. I believe a woman could do it. 

The Chairman said he regretted to tell Mr. Rose the Tribunal 
could not agree with the Local Tribunal that the claim made by 
hira for Mr. Manners justified the exemption that had been granted. 
They had to look at the national importance of the business claim, 
and they could not find in this case sufficient to justify exemption. 
They appreciated Mr. Rose's services to the country, but they could 
not allow thoee services to entitle the claim for exemption which 
was not supported on other grounds of national importance, but 
they would allow the fullest time they were accustomed to give- 
two months — and at the end of that time Mr. Manners would have 
to be available for service. 



Corresponaence* 



J 



- • Correspondents should never write on both sides of the paper. N9 
notice is taken of communications unless t)ie names and addresser 
ef tlie writers are given. 

. * We do not undertake responsibility for the opinions expressea ay- 
our corresvondcnts. 

SHARP ENLARGEMENTS. 
To the Editors. 

Gentlemen, — -Adverting to the paragraph on page 86 of the- 
"Journal," it does not appear to be generally known, that a good 
focussing magnifier, adjusted to the user's eye and fixed in a hole' 
cut at the centre of the enlarging easel, with the'front surface of 
the magnifier in tlie same plane as the front of the easel, enables- 
sharp enlargementfi to be made quite easily. 

The enlargement is first roughly focussed to size on the front of 
the easel, and the final adjustment is then made by slightly moving 
the easel to and fro whilst the eye is applied to the magnifier. When 
the definition is perfect the grain of the negative will be seea 
through the magnifier. — Faithfully yours, 

Clembnt J. Leapek. 

Galway, February 26, 1918. 



HYPO RECOVERY. 
To the Editors. 

Gentlemen, — iMr. .S. F. E. Jolmson's experiment is intei-esting,. 
but I fear he has overlooked a rather important point. A result 
similar to his is qu-ite easily obtained by adding ammonia only to- 
the used fixing bath, and without resorting to tJie precipitation of 
!t)he sulphide at all. I think if he goes into tlie matter again hfr 
will find that instead of recovering or restoring the hypo he ha«- 
'simiply com-erted the unused hypo left in the original bath into 
Ijhe much quicker-acting ammoniuim compound, which, experience- 
seems to show, is not a very reliable fixing agent. 

I have just completed a long series of exiperimente on this suib-- 
ject, all of which tend to sho.v ithat the hypo actually employed; 
in the fixing process is iri'ecoveralble by any simple means, sijnqxly 
because it no longer . exists in its original form, but has assumed 
that of a different compound aJtogether. The results are now 
being put .together for publication, and I hojie to have all complete* 
very sh-ortly.- Yours faithfully, 

'.March 2, 1918. C. Welboene Pipbb. 



Jdarrh o, i::*lb.j 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



119 



PLATE SIZES. 
To the EdiUirs. 
Gentiemen, — For laodacmpe work 7J. z S i< no doobt the best 
;iie and ih«pe for leriotu amateurs, but they are not very numerous. 
For some time before the war even ^plate camera* were going 
hca,p, because the average amateor winted lomething smaller, and 
i'>mand for anything bij^er than postcard ia not likely to be 
■d after the war. It is a pity our manufacturers did not 
adopt either 6 x 4 or the Continental equivalent — 15 z 10 cm. — as 
the standard plat« for postcard views. 

For profcasional use 7^ z 5 is leas u^^eful tliaii 1/1, and I question 
whether Kodak Co. will "strike ile " with their 11 z 7. 11 z 8 
%<ronld have stood a, chance, as though 10 z 8 has not been very 
iar.'Hiy osed in England, it is a useful size, and what 10 z 8 cameras 
are about are, judging by the advertisements, being used up, 
...^ the extra 1 in. in new cameras would have been no disadvan- 
tage for .{roups. — Yours truly, W. Cous. 

DEVELOPER POISONING. 
To the Editors. 
II.— In reply to Mr. C. .M. Foator, may I respectfully 
hat I imagine nothing — I never do, a"H ■<.>^.>r intend to 
' has it p ass e d through my ima^:i' n cfiinion) 

I - —'■ he was of • bloodthirsty natim, a.;...^..^.. it* may be 

« sportsman. 

Vo« Mr. Foster even goes so far as to compare the «o«rc« of his 

with mft*lf as being a member of the Pharmaceutical 

"'* don't do this; I may b« thtek-skinned, bat I hardly 

I am sure no chemist woold wnt« snch a ludicrous 

i oster is not content with giving a recipe which is 

.' inaccurate as published in the "Britbh Phannaoeutical 

™.i," bat now tts* IT not b« tha on* in the " British 

t' hwm ac o i w sia " '. W -ter take HHttm me, without argu- 

inmt, that Ung. Meti.j. ..^...1 Co. is not pnUished in the prsaent 

• •1 ;.<jn of the "British Pbatwiacopo-ia," nor ha« it evei» bMa in 
f'lnoer onesT Jajus DuimjN}. 

Ventoor, February 28, 1918. 

VVh^ I' .:r' :^^ iasoo really is lint .Mr. Furter discovered a pre- 

' . whether right or wrong, cored Aim, and in all good 

"iicrcd It to others afflicted as he was. A» we have so often 

' d oat when dealing with Uiii question, a rtotedy that will cure 

ne will not loorh another, tio far as we ai« eoaeanied, the matter 

I* BOW ended.— En. "B.J."] 

ExHiMTioM or Samtlks or Oraiu.N aitb AonKuii Goods.— At 
'he invitetion of Sir WiUiam Clark, o{ the Coomcraat Intelligeoce 
Iiepertnent, Board of Trade, representativse vt trade and technical 
juanials attended at 73, Baaingball Streai. tJC., on Manrh 4, to 
view tha exhibition of samplsa now on viaw. Sir William, in a 
«hart speech, explained the objects o( tha exhibition, and drew 
ktientioa to the suer— with which Uie schtma had met ap to the 
vraaeol, huaJreda o( British firms having already stadied the 
•saaiplea aiasi carefolly daring 1917 al'iie. In the proviacea 15,000 
roanitfactorers aad nerchenta have examined theai ap to tha present, 
while 1,236 taaplea have been lent for copying pa r pose a . The 
-ihibitioa ia arntogad to show the quality, design, suid style of 
^■no(b in popolar demand in various parte e( the world, anid the 
jirices, discoanta, and terms of caedit allowed by the Gennaa mano- 
fictarers. The Department can sopplv Befohaate with the names 

''-lUah Baaofactarcra sopplyiag similar goods, and manofaetarert 
' .':• the nam Si of oveneaa bayers. Further, they are prepared to 
iaad aaaaplaa to any 6rms de^roos of copying tbaoi, sod to give 
letaila oooceraing tariffs, (raighls, oommercial eaatoais, etc, to any 
trms desiring new fcmign markets. The eoiiibitian includes aboat 
! 5,000 aamptes in a great variety of tradca,and about 1,000 of the 

• kmplea are new, having only been manafaetored aiaca the war 
"egan. We ooold, however, find only eoe sotiiery photographic 
■ «.hibit, in the shape of a folding camen ol ordinary type. The 

i'lality variaa frov the cheapest possible rabbiah. desienpd for selling 

■■• natives, up to goods of fair quality, bat lher> irh of the 

.Tim! (itia!ity enemy work in evidence. Hie e.\: .< an excel- 

■•>T the trades thet it hicludes, and we should like to see 

...... .^tended to cover the numerr>aa photographic manufactures 

'ith which photographers have been so bonntifnUy supplied in the 



iinsiDcrs ro CorresponaentSe 

* — 

SPECIAL NOTICE. 
In eomtqiience of gentral reduced tvppliet of paper, at the resul t 
of proUbition of the importation of mu ch wood pulp and grasf, 
a tmaUer tpaee vill be availabh until further notice jor r eplies 
to eoTTUponden ts. 

Uortootr, ice will answer by pott if stamped and addressed enve- 
lope is enclosed for replji, .- S-cent InUmational Coupon, fro m 
readers abroad . 

The fvO questions and answers tctO be printed only in the case of 
inquiries of general interest. 

Queries to be answered in the Friday's " Journal " must reach us 
not laUr than Tuesday [posted Monday), and should be 
addressed to the Edijprs . ■ ~ 

Aac Lamp Glasscs.— Can yoo infonn me how to prevent the inside 
of (he cylinder of enoloaed arc from quickly becoming coated 
with white deposit? — J. 

Your cyjinder doee not fit olaaely enoogh to the top and bottom 
plates, of perhaps you have a amaH piece chipped out of the edge. 

Embokmno Postcarb noRDKRS.— Could you inform mo where I 
eould obtaic a m«hine for embossing the floral borders on post- 
cards same as enclosed card?— J. 6. 

The necessary trsss btecks can be obtained from Messra. Knights 
and Cottrtll, 6, Tudor Street, B.C. Presses from Messrs. Hughes 
and Kiniber. 9, Oough Sqaara, or other large printers" engineers. 

Emclsion ron Exnnn Coimuns.— We fear we cannot help you 
very much, but consider that the effects you want should be best 
aecured with a slow, fine-grain, richly-coated emulsion, containing 
io<lide. We do not know of aOy special ingredienU that will help 
the effect, and believe it to be a fact that much more depends on 
the skill and experience of the emulsion maker than upon the 
formula used. 

CnxvLOID, tic. — (1) The only photographic i^e for the celluloid 
woold be to make carbon miniatures upon tcit colouring ; the sur- 
face would want finishing with fine pumice. (2) The red colour 
has faded out. Nearly all reds and pinks arc fugitive, and car- 
mine and crimson lake are the worst. Rose madder is the most 
IMTTiianent pink. Be very careful only to use the best colours. 
Mij»t " stujents' " colours fade. 

Valcx or I.E.Ns.- Your (Ascription of the lens is altogedier too 
vagne for u» Uj idorrtifv. It may be a rapid rtotilinear, a wide- 
aqgle, or a Holast<t;mat, and in aoch case the value and capabili- 
tiaa would differ widely. The number you quote is only a serial 
namher, and doee not give us any information. If you care to 
send us the lens, with stamp* for return postage, we ahoold be 
pleased to give you some idea of its capabilities. 

Gnocps A!n> FcxLtXNOTHS.— Will yon let me know the best kind of 
a lens to get for taking fall-lengths and groups in a studio which 
is 16 ft. long? I want one with good definition and very quick 
acting.— C. B. 

Yoa will do best with aa anasUgmat of not more than 8 in. 
Trylii"r*^ and an apertare of /'/4.5. This -will cover the half- 
plate well at full aperture. Yoo should not attempt large heads 
with this, but up to, say, 1^ in. there ahould be no apparent 
distortion. 

Tbt roK RniDtTS.— If it is sulphide of silver, it will be a black 
compound, and will be soluble in warm dilute nitric acid (about 
1 to 3 of water). If you take a little of the solution, dilute it, 
then add a strong solution of nit, white silver chloride will come 
down. This you can identify caaily, for it will be soluble in 
ammonia, and will be precipitated again for the solution by adding 
a few drop* of sulphuric acid. For the test you need only take 
a very minota portion of the sludge, and if it proves to be silver 
yoa can then collect the lot and send it to the rofincrs. You 
should also teet the li<|uor in the barrel by taking out a little 
and adding to it a dr<jp of sulphide solution. A black precipitate 
will show that all the silver has not" yet been thrown down. 



120 



THK liHillaH JoLHNAL Oi- PHOTOGRAPHY. 



[March 8, 1918. 



Sci'PLEMEN'TABY Le.vs. — PleSBC tell me if it is possible to use a 
sui>plenientary lena to halve the focus — viz., to make an eight- 
incli //8 lens into a four-inch fj^'i If so, what supplementary 
lens shall I require, and where can I get it? — E. G. A. P. 

Yes, you will require another eight-inch lens. The only com- 
mercial article is the copying planiscope., sold by Griffins, Kings- 
way. Or you might get an eight-inch single landscape lens ani 
fit it yourself. 

Pybo DuvBirOPKB. — Can you say what becomes of the pyro in 
ordinary P.S or P. ammonia development? What does it decom- 
|)Ose into, and can you refer to any published statement? Have 
looked at Fownee and Rosooe and Sc-horlmer, but they don't 
touch it, and I have no other handy. I may have one of Abney'e, 
but can't put my hand on it. — " PyRO." 

The pyro is oxidised, 'but nothing is known with regard to the 
I'xact composition of the oxidation product. 

FiiRTBArr Lens. — The lens appears to be a cabinet portrait lens of 
about 10 in. focal length with an aperture of /'/4. These usually 
require stopping down considerably to cover the standing figure, 
as there is considerable curvature of field. You could uso tlie 
front lens alone for large heads. It will probably have a focal 
length of about 14 in., and -would give suflicient sharpness at an 
actual ,ij)erture of about F jlO (not //lO of the complete lens). 
You must judge the instrument on its merits. Do not buy unless 
you are satisfied ; its value is probably £3 to £4. 

Stui>io. — 1. The precise tint of the studio avails is of little moment ; 
it ia rather a question of their reflecting power. For a well-lighted 
studio wo thirik that light grey or cream is rather apt to give 
a flat lighting ; wo should prefer a greenish grey. If your light 
is at all obstructed, light walls -will be an advantage. 2. A good 
distemper is quite suitable. 3. To take seven full-length figures 
the oblong way of a half-plate you will have to use an 85 in. 
lens. If you can use the plate upright, a 10 in. lens wiU do. 
4. No, so long as they are placed so as not to throw strong 
reflected lights on the sitter. 

Dami" Cabinet. — I have a cabinet in my reception room in which 
I have been keeping leather -vviallets and miniature casee. I find 
they are all going spotty with mildew, owing, evidently, to damp 
or mildew germs in the cabinet. Can yon advise me what to 
do to make the cabinet safe for such goods? 

Keep a lump of quioklime or a little chloride of oakium in an 
ornamental vessel, not covered, in the cupboard. This will keep 
t)he air dry. When the lime falls to powder renew it, or if you 
use csdcium chloride dry it in an old pan,*>ver a good fire. Do 
not leave the cabinet open longer than you can help. 

STCnio. — We wish to fit up a room 14 feet by 15 as a studio, and 
have in use a 7i-inch lens workinig at 5.4, and a Ross Telocentric 
13-inch 5.4. We do not intend using anything larger than 2- 
plates, and should like to use half-watt portrait lamps. The room 
is only 9 feet high, and is the only one we can spare for the pur- 
pose. Will you kfndly help us as to colour of walls, power, and 
position of lamps to get fully-exposed negatives with Wellington 
anti-screen plates in half a second to one second ? — G. G. B. 

You will require four or five 1,000 c.p. lamps, arranged as given 
in our article of October 26, 1917. The walls must be of a light 
grey if you wish to give such short exposures. 

Blue Spots on Prints. — I am sending along for your inspection and 
advice several prints showing a bluish stain. These stains, we 
think, are caused in the hypo fixing bath ; the hypo used is some 
we bought a short time ago and paid 60s. per cwt. for. I am 
sending you a sample of the hypo, and shall be glad if' you could 
tell me if this is faulty. I made a further batch of prints, using 
a different make of hypo, and these turned out all right. This is 
what makes me think that hypo is the cause. — H. D. 

The hypo does not appear to be in fault, although it is rather 
a dirty sample. We should advise you to strain it before use, as 
the black particles may scratch the surface. We cannot identify 
the staining material. It is not violet dye, nor does it appear 
to be metallic. From testa we made, it appeam more like a vege- 
table dye, which has been splashed on either in the washing or 
fixing. 



Studio Lighting. — In your almanac, just published, for 1918 there 
is a description for lighting a studio with two half-watt lamps 
of 2,000 candle-power, each fitted on a telescopic stand, the lampe 
6 inches from each other, and a white blind as a reflector. I am 
wanting to light a small studio about 12 x 8, but require the light 
for both heads and small groups of, say, three or four persons, 
sometimes. Which would be the better arrangement for me? 
(1) The two lamps on two separate stands, with loose flex to give 
more diffused lighting rather than the .two together; or (2) 4' 
carbon north light or 5 carbon tress ; or (5) a Jandus or West- 
minster arc lamp; and would one be sufficient? Also say what 
height from floor to light is necessary, as studio is not very high. 
With a 3D DaJlmeyer, working at F. 6, what exposure would be 
necessary with a plate working, say, 300 H. and D. ?— Bebt. 

We think the best arrangement will be to have the standard 
you first mention, with a longer arm, so that you can separate- 
the two lamps to, gay, 18 in. distance. You will find two stan- 
dards in the way in so narrow a studio. The exposure would be 
about 3 or 4 seconds. -Much depends on the distance between 
lamp and sitter. Next to this we would reconmiend the enclosed 
arc. In any case, the light should be capable of being raised 
to 8 ft. from the floor for full-lengths and groups. The Kodak 
" Toplight " arc is good for tliis; the Jandus and ordinary West- 
minster type require more head room The half-watts may be 
arranged quite close to the ceiling. 



New iliLiTARY Pkohibiiion of Photography.— Orders have been 
made by the competent niiUtaiy autliorities, under tlie Defence of 
the Realm Regulations, proliibiting the making, after ne.xt Monday, 
of any photograph, sketch, plan, model "or other representation 
of any place or thing " within the area mentioned. \o person 
in this eirea shall, witiiout lawful authority or e.xcuse, have :n his 
jwssesaion any photographic oi- other apparatus, " or otlier material, 
or thing suitable for use in making any such representation." 
Nothing in the Order is to be construed as prohibiting the making 
of a photograph, sketch, plan, model, or other representation in 
any photflgrapliic or other studio, or a private dwelling-house, or 
the garden or other premises attached thereto, of any person or 
things thej-ein, or as prohibiting the possession of pliotographic or 
other apparatus, materials, or things intended solely for use in such 
studio, dwelling-house, or other premises. The area affected con- 
sists of certain places in the Metropolitan Police District and cer- 
tain areas in the counties of Essex, Kent, and Surrey. 

%\it l^ritisb Imtmal of ^Pbutograpbg. 

The Oldest Pbotographio Journal in the World. 
PUBLISHED EVERY FRIDAY. Established 1854. PRICE TWOPENCE. 



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IMPORTANT NOTICE TO READERS.— Until furlUr notice 
agents mil supply the " B. J." to order only, as " returns " are no 
longer accepted by the publishers. This step has become necessary 
owing to the further restrictions imposed by the Oovernment on the 
importation of paper and paper-making materials and of the eon- 
sequent shortage of supplies. It is therefore necessary in order to 
ensure the regular delivery of tlie "B.J." each week to place an 
order definitely with a dealer, newsagent or book-stall clerk, or to 
send a subscription to tlie jntblishers. 



THE BRITISH 



JOURNAL OF PH0T06KAPHT. 



No. 3019. Vol.. LXV. 



FRIDAY, MARCH 15, 1918. 



Pbice Twopence.' 



Contents. 



u in 


rjuti 
Scwi AID HMm 129 


uTtoaK » _ m 

• orPaoTO- 
•baaUjr.. US 
." or Lcno 
. «a4H.L8huJu IM 
■ ' U« 

m 


OOBUUroHMMoa >— 
ao<l WMOT m4 BthMn-Oe- 
TalupOT tat Piaem Work ■ 
Tbr Cotafiat fcww o( % Lwm 
— H7P» Baaerwy— TMik D*- 
iil iliiiil UO-lil 









8UMMAAY. 

I ivrthtr uuUliMni of Um Tniil Taylor l<*ctun bjr Mr. C. H. 
nicy dcab with the ohiOBiiiUB iatan^fiar, for which Mr. 
iloy liftml teversl kltanMtiva formula. Ooa of Uicm differ* 
ID makiog uw of hy<iioohlorio acid of 10 nar emt. akreoi^h 
I of Um itrong acid, tbu making it aacMr lor the radaoor tu 
I oorractly oompoondad aa raguda tha (imporUirt) pro|>orUon 
A tacond formula eoMiaia of a murtart of cbmiiuc add 
t, and ««a fonad lo pr» a dapao of inta—ificrtioa eomapood- 
^jrith Um a ckraniam fonDala aa printad in Uia "Almaaac." 

iMiladiM fiortioa of Uia {Mpar on Uia axial abamtion* o( 

Miala tar Um moat i>art of corrca ahowing ttM raaolu 

by tKa application of a OMdified Hartaunn mathod. A« 

out in toBM notca on tha wbola papw, it •boold ba rtoog- 

thal thaaa diagiama illoatrata tha dagrat of eorraction oa tha 

ily, and muat not be takan aa indicating parfoHBanoa of the 

in tik» wa^ of ooTering power. (Pp. 12s and ^2^.) 

aee o( adviea which wo aava giveo befon, bat which ia tbaae 

of anhancr.! uUU prioaa will bear rrpa t itioB, ia that pboto- 

lan »b«'. '" their own Mtiafactioa tha good raaolu in 

ny of ]•■ '"hicb are wiUiui their nmeh by taking the 

'<« and cnUr^ing tram lh«0. Battcr-clau 

take a hint (rum the ehaapir portrait biui 

m uiiiuiing IU.M maa a oia of eoommy. (P. 122.) 



lo a qnaation aakad in the Bonaa of Commone in 

to tha Maoiorial Portrait SclMme of tha National Portrait 

haa not, aa might bare bean anticipatad, alieitrd anyttiiiik' 

leation of tha riolant attacka tome montha ago of the pp>- 

Pbotographer*' Aaaociation. I ' 

i corr aap ondaat who haa lived in tw> one aarred with a 

»ft water aupply and tha other wiui one ol ooaaidermbte hard- 

-writra to eonfirm tha very gnM effect of ((oality in the waah- 

tha blialwtng of prinU tn ao!r'' '- '"^ nx. (P. 130 ) 

the notic* laal week tK* >ble area* in the 

I of London ata now the < in Order prohib^t- 

ranby, and even (oalaaa under ppnniaaion) the poaaaaaion 
aphio apparatoa, wa no>w pobluh a Ibt of thx amta :ii 
'and tha addrew of tha aothohty to whom m 

I to permita to photograph may he addreaaad. 
Icing method lor tha production of viatJno-auriit'r rjnv.n 
I ia ««fUiy of notice at tha preamt lime or phdlognpheri who 
itifBcnltv in getting platinum p:ip<>r. (P. 12L) 

iiMit givea a nnmbrr of hinu drawn frrmi lii.i own 
th^ m^ fit a tank m«-'hof| <.' iFretopmaoi. (P. 131 ) 

--h may be appli*^! 

M be placed in the 

a pont^rspn o't p^'je L^l. 

-ncrican eoalampora'ry to " adaHaranU " of 

•ay aomethinff of tha two anbatancee chiefly 

nely, carbonate and anlpbete. In low-i^radV 

inioant of imporitv may ba preaent, and lacli 

itt9 iwit to oaeleaa (or photographic pnrpoaee. (P. 122.) 



EX-CATHEDRA. 



Platino 
Surface 
Carbons 



In view of the growing difficulty of 
obtaining platinum papers and the 
ever- increasing cost, it may be useful to 
rtiii::. i ti.- profession of a method of making carbon 
pi in;,- wiL.-u are entirely free from gloss even in the 
deepeoi ahadtfws. The procedure is, if anything, more 
simple than that ueu&lly practised, and there is no addi- 
tional outlay beyond the purciiaae of opal glass to serve as 
a temporary aupport in place of the usual "flexible." 
The opal glass muat be finely ground, and it is desirable 
before taking it into use to smooth it a little with a flat 
piece of hard wood and a little emery jiowder and water. 
If the opal has a " satiny " feel to the finger this will not 
be necessary, and the preparation of the surface may be 
procee d ed with. This is nothing more than well rubbing 
with powdered steatite or French chalk, which is dusted 
on or, better still, scraped from the lump with a knife. 
The powder must be rubbed on with a pad of cloth or 
flanf^l, considerable pressure being applied during the 
process, the rarplue being wiped off with 9 soft duster. 
The exposed tissue is mounted and developed and trans- 
ferred in the ordinary manner. It will be found that the 
prints strip easily, u.iually falling off the opale as they 
stand in the drying racks. It is worth noting that it is 
mtKh easier to work with freshly sensiti!<ed tissue than that 
which has been allowed to become " ripe." If very hot 
water or soda has (o be used to obtain tlean prints there 
is a much greater chance of the tissue sticking to the 
temporary support than when development has been 
carried through at a lower temperature. 
• • • 

Artifloial We have pointed out on more than one 

Lighting. occasion that the design of the studio 

does not affect the lighting of the model, that being 
entirely controlled by the direction and volume of the light 
admitted. It should be obvious to anyone who had taken 
a portrait by daylight that the same principle would bo 
eqaalApM^licable to artificial lighting, but judging from 
the nomher of inrjuiries we receive it would seem not to 
bet'' "1 The simplest plan for placing an 

arti! tallation is to put yourself in the 

position you it.leud the sitter to occupy when making 
plain three-quarter light pictures, and to place the light 
where you would expoot to find the opening in the blinds 
of a daylight studio. After this it is only a matter of 
diffusion and reflection. When fitting lamps into an 
ordinary studio it will usually be found inconvenient to 
fix them between the glass and the sitter. In such cases 
it is best to put them on the solid roof side of the studio 
and light the sitter from that side, and if the construction 
of the studio will allow it, at the other end of the roof, su 



122 



TKK UKlJlsH JOUK-NAL UF I'HUIXJGKAI'HY. 



IMardi 15, 1918. 



that the same side of the sitter's face can be taken fcy 
«ither day or artificial light. In an ordinary room it is 
simply a matter of arranging the sitter and light in the 
most convenient way. We have noticed, by tJie way, that 
■when fitting half-watt lamps there is a tendency to place 
i.hem too much to one side and also to have them too low. 
Another hint which cannot be repeated too often is t« 
remember that neither the sitter nor the camera is screwed 
to the floor. Many photographers work as if the camera 
ran on a tramway and take infinite pains in adjusting 
blinds, when the same effect could he obtained by slightly 
turning the sitter and bringing the camera into such a 
position as will give the desired pose. 
« « • 

Sodium In an article in our American con- 

Sulphite, temporary '' Tho Camera " references 

are made to the presence of canbonato and sul/phate as 
" adulterants" in sodium sulphite, which seems hardly a 
fair way of describing the facts. No dou.bt both in- 
gredients can be used as adulterants, but still their 
presence in no way proves that the chemical has been 
adulterated, for one, the carbonate, is there almost of 
necessity as a consequence oi the method of manufacture, 
■vifl;lile the other, the sulphate, is bound to appear as the 
result of oxidation even if not present in the beginning. 
Some time ago we had ocxjasion to test a very large numfber 
of samples, including tie purest then obtaina.ble, and all 
contained from 2 to 5 per cent, of carbonate. No doubt 
this unwanted alkaline ingredient sometimes gives trouble, 
especially with developers that do not keep well with alkali, 
hence no doubt the success of the combination, of sulphite 
and acid sulphite now so frequently used. Our con- 
temporary also refers to hypo as an occasional adulterant. 
This certainly has no excuse for being present, but while 
we have often looked for it we never yet found any ap- 
preciable trace of it in any sulphite sample. There are, 
however, cheap sulphites that oo itain many things in 
addition to large quantities of sulphate produced by de- 
terioration. Some contain impurities to the extent of 50 
|)er cent., hence it is always advisable to order only a good 
reliable brand and to pay a fair price for it. Some cheap 
samples are ne:it to useless. 

* » « 



The Plate 
Bill. 



The continued increase in the price of 
plates, impels us tx) recur to the question 
of economising by adopting smaller sizes for original nega- 
tives, and enlarging from these for the bulk of the work. 
One successful American portraitist testified t« the success 
of this method, using only a 5 by 4 camera and enlarging as 
a rule to 10 by 8. Those who still use platinum and other 
printing-out papers must, of coui'se, make their negatives 
the full size of the prints, but the majority of studios now 
employ one or other of the numerous developing papers, so 
that there should be no difiiculty in this direction. Nor 
need there be any misgivings as to the quality of the results, 
since it is generally agreed that an enlargement from a 
negative of average quality compares favourably with a 
contact print ; in fact, one of the most experienced trade 
printers in this country assured us that even for same-sized 
copies he preferred to do them "through the lens." The 
only doubt which many workers will have is whether the 
extra labour necessitated will not counterbalance any 
saving which may be effected in the cost of plates. If 
proper arrangements are made, there is no extra labour 
needed ; in fact, the printer ne€>d hardly be aware that he 
is not making contact prints. The cheap postcard man 
almost invariably enlarges from a very small negative, and 
that with very primitive appliances. If the image had to be 
focussed for each negative, and the paper pinned up or 



centred in a frame, time would be lost, but it is perfectly 
easy to fit up a vertical enlarger with the light and lens 
either above or below the negative, so that in the one case 
the image is projected upon a table on which the paper is 
laid either iinder a mask or under a piece of glass, and in 
the other a frame and glass plate is used as in an ordinary 
printing-box. If gaslight is the only illuminant available 
the foniier arrangement is used ; if an incandescent electric- 
lamp can be fitted, either plan may be adopted as preferred. 
Taking the case of ordinary cabinets, a quarter-plate or 
even the 3i by 21 size will suffice for the negatives, and 
those who have not tried working on these lines will be 
surprised at the short exposures necessary and the good 
definition over various planes which can be obtained. There 
are many short-focus portrait-lenses which will Cover a 
c.d.v. at //3, and the negatives will yield enlargements in 
every way equal to prints from larger direct negatives. 



AXIAL ABERRATIONS. 

The paper on the axial aberrations of lenses by Messrs. 
Tillyer and Shultz, which we have reprinted from the Scien- 
tific Papers of the Bureau of Standards, Washington, 
U.S.A., forms a very valuable addition to optical litera- 
ture. Optics is now receiving a great deal of attention in 
America, and the value of the American publications seems 
to be steadily increasing ; a fact that we are very pleased to 
note, though we should be still better pleased if England 
showed more signs of progress in the same direction. 

The main purpose of the paper is the demonstration of a 
system of measuring the axial aberrations of lenses, founded 
on the Hartmann method, but much improved. A very 
important feature is, however, the first part of the paper, 
which is devoted to the consideration of the errors affecting 
the image, and includes an admirable demonstration of 
zonal aberration and the sine condition ; subjects which are 
seldom well treated by optical writers, partly, because they 
are complex and difficult to explain, and partly because 
the sine condition, in particular, is capable of several de- 
finitions. The authors appear to adopt the views of the 
Jena School in regard to this matter, but they succeed in 
giving a very clear exposition and explanation of what is a 
rather difficult subject. They seem, however, rather to take 
it for granted that the fulfihnent of the sine condition is an 
essential thing in the perfect lens, though this is a point 
that has been much disputed, and seems open to great 
doubt. 

The principle of the testing method is simplicity itself. 
though its application requires very delicate adjustments 
and measurement. It depends simply on putting a metal 
plate in front of the lens, perforated with small holes, which 
isolate ipinute beams of light. The course that these beams 
take is recorded on photographic plates, put at varying 
distances from the lens on its other side, and the relative 
positions of the plates being known, it is, of course, possible 
to calculate the exact course of the beams, and to ascertain 
how their central rays intersect one another ; or, in other 
words, what kind of a focus they produce. The authors 
state that by selecting holes of suitable diameter they get 
good diffraction discs on the plates, which discs can readilv 
be centred. This is where one of the delicate adjustments 
comes in, for if ill-defined patches alone are secured, it is 
obviously difficult to determine exactly w^hat point in the 
patch should be taken. It also strikes us as the weak point 
in the system, for it is obvious that a very little carelessness 
or uncertainty in fixing the critical point for me.-.surement 
may lead to serious error. 

It is, of course, obvious that there is nothine new about 
the method of isolating small beams by means of a per- 



MarA 15. Idiai 



THE BRITISH JOURNAL OF PHOTOGRAPHY 



123 



forat«d plat«. aird then tracing their i-^urse. Hartmann was 
apparently the first to use it for khs testing, but others 
have frequently used it for optical 1 1. 'monst ration purpose?, 
and for uiofJelling light- pencils. If the photographic records 
made on either side of the focus are reproduced in the form 
of perforated plates, these plates are set up opposite to each 
other, and the corresponding hole« are connected with 
threads, very complete and instructive models are readily 
prciuced, which will convey more information in a few 
miiHites. with regard to the action of a lens, than a long 
cowr^ of study of optical hooka will afford. A set of models 
of this kind was exhibitetl at the R.P.S. Exhibition some 
years ago, while we believe that South Kensington has long 
pr.:;<>jsed some other models made on similar principles. 

Tli« examples of plotted results are interesting, and 
wouM ht- pvon more so if we knew the names of the lenses. 
It i- ir-'^-iting to note the high decree of correction that 
t). ion lenses of the Petnal type show, and the 

ap, -irge variations evidence*! by the anasfigmata. 

It is perhaps necesMiry to warn readers that these diagrams 



illustrate the degree of correction on the axis only. The 
side scale marked "distance from centre of lens" refers 
only to the lateral distance of the hole in the perforated 
plate from the axis, or, in other words, fives the measure 
of half the diameter of the stop aperture, upon the circum- 
ference of which that hole is supposed to be situated. These 
figures have nothing to do with the diameter of the field 
covered on a plate placed at the focus, which will, perhaps, 
be the first impression conveyed by the diagrams. On the 
contrary this field is assumed to be very minute and situated 
on the "axis, axial aberration alone being considered in this 
paper. This point must be borne in mind throughout, 
especially in the case of the anastigmats, which, as we have 
often pointed out before, and as the authors again point 
out in their paper, are very often intentionally left rather 
poorly corrected on the axis, in order that better r«Mults 
may be secured near the margins of the wide field required. 
A photographic lens is essentiallv a thing of compromises : 
for more is required of it than can ever be fulfilled perfectlv 
throaghout. 



SOME MINOR PROCESSES OF PHOTOGRAPHY. 

1 • I • 

The Twtntkih TnullTaylor Meiiiori«l I^eetuns delivered before the Royal Photographic Society by C. H. Bothamley, 

M.ao.* I'.l.V'.^ 



{C<mlmii*d from page 113.) 

In -hi* proc««, which wm w.»rke.| ..ut in detail. Uiough not 

vented, bv C. WelU>me Piper and the Ute D. J. 

Amat- Phot.,' 1904. pp 336 und 307. und 1906, 

pp. 463, 473). the ni-K»tive is 'f P<'t»»- 

.Mi'M hi.hromato acidilieil » . , and the 

1 I. > li^d image, after wanhing, is treated with an ordinary 

I>er. According to Piper and Carnegie, the bleached 

'-ontain* a chromiam compound, which they suggeat may 

,.,..!,. I .1,1 iniiim dioxide, <V» -- -rully regarded 

1 , , 1-. ( I (,. They e<»t.i ii« p r e— B OB ol 

but not the precise nature -l the chromium 

I mada espwimeir '"> •• ♦" 

■•.v:ictmodeo(a< u of purr 

ic acid alone, 2 part* in 100, act* readily on negative and 

v« iinagM, and in time will completdy mnore the ailrer 

«v«B a dcoM iMgstiTe if a snlicient Tolnnie of the lolation 

■ iMed. [SpeebMii akowB.] 

A «akition eDntBtetng cmly S part* 'i( ofaromic add in 1,000 

.1 water also baa a distinct, thoui{h alo* ' ng adaon. 

ih-r-r i< diMolwd as ■ilvw chrr-mate rt ol the 

reduced to the ooii mic »ah ; the 

i.-lin* OOBMlB of QT).' 

A 6 per cent, solation of verj- .ai-fuUy purified potassium 

'->.r,.inate, free from chloride* ami free from efaromic acid, 

.. action, «rm »tUt 48 hofln" ima»«nioB, on a negative 

h«s been wwhed free from rhloridw. Similar resulu 

'•^ined with Ustvm »lide», notwi^Unding the finer 

•n rontaining pure potaanam bichromate 
;00> usi'i '-'* chromic acid, also baa no 

•■!«nble s< • ii«K^- 

^n that the hlrarliiwg e0ect is do* t 'iltaneons 

hromic acid and potassium cUor "d by the 

nf the hydrochloric acid on the potaa^ romate. 

:i(i. in fact, that a tolatton containbg ; r<>mic acid 

;.iiro salt readily bleaches iiWer imagea, with rssults not 

hable fro«n thoa* obtained «ith a solution of bidiro- 

^1 yeHh hydrodilaric acid. 



I alao made some experiments concerning the composition of 
the bleached image. It cle.nrly does not consist of pure ailvei 
chloride, because it has a pronounced brown colour, much more 
distinct with formula A than with formula C (see below). There 
i«, in fact, no difficulty in detecting the presence of chromium, 
by the ordinary tests, in both the bleached and the redeveloped 
image, though the proportion seems to be smaller in the latter. 

Further, if the bleached and thoroughly washed image is care- 
fully treated with a dilute solution of caustic potash, potassium 
chromate paasM into the liquid and gives it a yellow colour. If 
now the negative is again well washed the image is still found 
lo contain chromium, but only in the basic cfaiTomic condition. 
// foUou-i thttt the hrovn conttihtrnt of tht, hleached image i» 
n chromic ehrnmnti. When the bleached image is treated with 
a developer this chromic chromate is reduced, and part at 
least of the chromiam remains in the chromic condition in 
the image, mixed with metallic silver. The amount of chro- 
mium ao left ia very small when the C formula is used. 

The thwe working formulss recommended by Piper and 
Cam^ie a„:- ^ ^ ,. 

Potassium bichromate... 5 grains 10 grains 10 grahas 
Uydrocliloric acid (sp. 

gr. II6O1 1 minim 5 minims 

Water V*""' ^ °^- 

or approximately — 

PoUaaium bichromate 10 parte 20 parts 20 parts 

HydrtKshlorio acid 

(sp. gr. 1160) 2 parts 10 parts 40 parta • 

Water ...up to 1000 parta 1000 parta 1000 porta 

TSSJ'lttlb that formula A gives a high degree of int«jaifica- 
tion, and formuU C a low degree, whilst formula B gi'ves an 
intermediate retnlt. The strip aegatrves shown on the screen 
ocmfirm litemt, statmnsnto. The dt^ree of intenm&wtaon ofc- 
Uiaed with B is nearer to that dbfained with A than to that 
obtwned with C. The result is determined by the relativo 
proportions of acid and bichromate and the proportion of 
acid ia the dominant factor. In ordt-r to obtain oonoordant 
rerolta with certainty, it is of great importance to make up 
tit.) formula with more than usual care and s«cnracy. It is 
unfortunate, therefore, that the formnlie aa commonly pub- 
Udted specify the oae of concentrated hydrochloric acid, which 



20 minims 
1 oz. 



124 



THE BRITISH JOURNAL OF PHOTOGRAPHY, 



IMardx 15, 191£. 



is not easily measured aocnivat«ly with the means usually at a 
Vbotojifrapher's disposal, «'s[«x-.ially when <init^ a small quan- 
tity is required, as with formula A. It is a much better plan 
to dilute the strong acid by adding 9 equal parts of water and 
:fcen measure out ten times the volume of dilute acid, so that 
ihe (ormulue would read : — 

AUG 
PotassiDin bichromate 10 parts 20 parts 20 parts 

Hydrochloric acid, 

dilute (1 in 10) 20 parts 100 parts 400 paKs 

Water up to 1000 parts 1000 parts 1000 parts 

Piper and Carnegie recommended amidol as the developer to 
be used after bleaching with the bichromate and washing. In 
my experlmonta, when formula A is used, the degree of in- 
tensification is the same, whether re-development is effected 
with amidol or diamidophenol, or with metol-hydroquinone, but 
with formula C the results indicate a slightjy lower degiiee of 
intenrification when metol-hydroquinone is used. 

With formula A the intensification is due in a substantial 
degi'ee to the chromium compound which has been added to 
thi) image; with formula C the intensification is mainly due 
to an increase in tho size and light-stopping power of the silver 
granules, due to their conversion into chloride and subsequent 
redevelopment (see W. T. P. Cunningham in "Phot. Journ.," 
Ivi. (1906), p. 2). 

Experiments were made with mixtures of chromic acid and 
purified common salt, the bleached image being afterwards re- 
developed with diamidophenol and sulphite. The chromic acid 
and salt are easily weighed out accurately, and separate stock- 
solutions, 1 in 10, can be kept unclianged for any lengt.h of 
lime. If the image is bleacJied with — 

Chromic acid 4 2)arts, - 

Salt (sodium chloride) 4 parts, 

Water up to 1,000 parts. 



and redeveloped, the result is practically identical with that 
given by I'iper and Carnegie's formula A. 

Some experiments were tried as to the influence of the rtJa- 
tive piioportions of acid and salt : — 

B E K 

Chromic acid 2J 5 2^ 

Salt (sodium chloride) 2J 21 5 

Water up to 1000 ICOO" 1000 

The intensification with U and F is identical, and is a iitile 
higher than with the stronger solutions given alxw*-. but tiie 
intensification obtained with E is distinctly lower than with 
D and F. Sections of tJie same strip negative weie truatwl 
with the different solutions, and tho measurements weit- ina/ie 
with a Sanger Shepherd densitometer. 

Densities. 

I) 4-7 7-0 90 12-5 15-3 17'3 

E 4-0 6-0 7-7 10-5 13 5 15-7 

!-■ 4-5 7-0 9-0 12-5 15-5 17-5 

The chi-oraium process is of great practical value, as masy 
have already recognised ; it is ea.sy to work, and if car© is 
taken in making up the bichromate and acid solution it gives 
concordant i-esults. Moreover, it is applicable to negatives, 
lantern slides, and bromide or gaslight prints. Formula C 
not only gives that slight degree of intensification which a 
print often needs, but may also greatly improve the colour of 
the image. With a still larger proportion of acid there ib 
still less intensification, but at the same time a distinct- im- 
provement of colour, if, for example, the original image hae 
had the well-known olive-green tint. 

C. H. BonUMLBY. 
(To be continued.) 



AXIAL ABERRATIONS OF LENSES. 



[We arc indebted to the Bureau of Standards of the United States Department of Commerce for the following paper, which deaJv 
with the chief axial aberrations of lenses and describes in detail the practical method worked out by the Bureau, based upon that ff 
Hartmann for the measurement and plotting of the aberrations. In reproducing the text of the paper, exigencies of space have compelled 
the omission of one section, namely, that dealing mathematically with the sources of error. A brief abstract of this section is inserted 
in the text as printed, in its appropriate place.— EDS. " B.J."] • 



(Continued from page 115.) 
The apparatus used consisted of the following :— 7? (Fig. 8) is a 
monochromatic source of light, which in this case was a Fuees 




Kig. 8 — Diagrammatic Slceiuh o( Apparatus. 

■lonoohromator giving a fairly pure band of tho spectram of about 
4,<,< in width in the violet (425/i,>) to aboiit 21/»jn in the red 
(fcSO/i/i). The illuminant was a Nernst filament close to the slit. 
The width of the band of spectrum was determined with a Hilger 
wave-length spectrometer, which had been checked up by means 
of a mercury arc. The monochromator was placed about 20 feet 
away from the screen, .and corrections applied to reduce the results 
to infinity. The screen S was a metal plate accurately centred with 
respect to the lens holder. The holes used for fairly large-sized 
lenses were 1 mm. in diameter, and spaced at intervals ©f 3 mm. 
ajart. For smaller lenses a screen with smaller holes spaced closer 
together was used, .permitting a suitable number of zones to be 
Jetcrmined. If the holes are too small or too near togethei', the 



diffraction discs will not be clearly defined, and it will be inufKis- 
sible to measure them. The lens holder, L, is of the iris <liia- 
phragm tj-pe, so that the lens is always centred witli respect to 
the holder, and therefore with respect to the screen. The lens 
holder rotates about a vertical axis, permitting the lens to he 
centred with respect to the photographic plate. The photographic 
plate P slides on an optical bench B B along a scale. The plate 
can be raised or lowered, pennltting several exposures to be miide 
on the same plate. 

2. Method of MANipniJiTioK. — The lens is placed dn the holder, 
care being taken that it is fairly well centred. It is then accu- 
rately centred by reflection from the back of the lens For this 
purpose a ground-glass plate with a little 90° prism cemented to 
iit (leaving a clear space in the gi-ound-gloss surrounding the prKsmI 
is placed in the plate-holder. The prism is used to send a beam of 
light to the rear lens surface. When the beam is reflected ob 
itself by the lens and comes back to the observer through tk« 
clear space around the prism, then tha lens is normal to the diret- 
tion of motion of the plate, and the centring is accurate. 

The monodiromator is then .<.6t to give a beam of wave lengt-h 
425/ifi, the plate placed at a cxmsiderable distance in front of the 
focus and an exposure made. The plate is then lowered, the mono- 
chromator changed to give a bcim of wave length 475/iu and another 
exposure made. This is rep'^.ijd with I' e monochromator set at 
550/(/i and 650/»ju. The plate i ■• then moved through a distance i, 
previously determined, so that the plate now comes behind the f<».uf. 



Hatch 15. 1918.] 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



125 



Tb« axposuras are rap««t«d through the wave lengths 650/i/i, SBO/iu., 
^Sit/i, uiU ASSfi/t. The length of e.xixieare ia timed so as to get 
maitann deneity on the plate for all ojloant, giving discs which can 
«asily bv measured on ^ Zeiss horizontal comparator or measuring 
engine with s nfBrimt aecorai^ for n>ys somewhat removed Iran the 
axis of the lens. 

LUere follows a mathematical discu>^ion of the effects of variou.i 
aooroes of error, it being proved that the effect of a slight tilting of 
the plate, and also of an error in tf, is negligible. In tk* casa of an 
srrjr in .i or 6, an error of Sa iu a, or 36 in 6 will cause an error in 

Uf— V). equal to d — or — -. F.rroci dse to iaaa«nrements. 
(I 6 

to irregnlarities in the i^ataa, and to dilfarent obaerTers, are as 

follows ;— The probable error of a sin^^le observation of two plates 

is 0.06mm. in V and 0.04mm. in E. The probable error of a tingle 

observation for two observers is 0.02mm. for V anJ 0.06mm. for 

'■ In plotting, the probable error is rednovd with th« valnas of 

100 
A /and .i Aby or inversely with the local length.— Kd'<. 

'•B.J."] 




V1(. 9. - [Ns«iam illtutntinc a tui of lb* pIsS* M Uis tn* ask. 

4. MtTiiOD or Purm^c. — Th« method of pliAtii^ the Msnlts 
has been described in Um ri is nu Mo n of ^iMrieal and sin* oondi- 
tioD aberrmtioas. The mwn value* for V and B w*i« so rhr»sn as 
U, show the plaoss <d had eofractioo of Uie lena« ia qoMtioo. 
Thus, the valaaa of the flnt liwo central toom in all oaa« wmn 
durega r ded (in «*hmg tha maao), as iJMm values ar« muaUabl*. 
In photagiifhic Ira s Si, wImm oo (nwiaiaa is made for Um oorreo- 
tioa of the fwi nj», (he mean of the }elIo«r.c(ota, bin*, and vioUt 
was takao. On lita other hand, in projaetioa and talaaoopa ' -|ii. 
the violet was disNgardad, and Um n.ran ol the rad, ydlow-giaeo, 
and bine was osed. The mean values o( V and £ ««« thao snb- 
ttaetad frm each of the vatoss ol V and E respectively, and tha 
lesolliag diflanocaa ladaeed to 100 niaa. focal length. ThiM pro-' 
cedoa* aahas tfio voitieal axis the mean valaa for both C and V. 
A dswjaatan from tha axis means a<i aberratioo. The doMad line 
ilMws the vahMJao of the E. F. L., and tha aoiid line shows the 
spherical abarratioo. Tht distance betwaan tha cnrves JHE and 
A r is a mcaaora ol tha CMoa. 

Tha earves for each wave length ar* pioMad separatel/, to as 
sot to create confusion, but th« vertioal axis reprtasnta the same 
line, and, for comparison, tha £gure« sboald be auparpoaad with 
the axes coinciding, or eisa «ha dmtanoaa tram X }' shoold tw 
crmparad 

The verlacal distanota k have b*'' n maghttad foor times, and 
tlir horiaootal diaCancas twenty tim-'s in acoocdanca with ooav«n. 
tion uaad bj Voo Bohr aad othan. 
la iNMra lengths used vara :— 



423 *Zl^i. (ai,. [Ill 

475 473,. 

&47 558«. 

447 6&W (abbot). 



43S 
475 
550 
650 



Deep violet 
Blua 

Yellow-gieen 
Bad 



The " limits of band " gives the width of the band of spaotrum 
used for each ooloor. 

5. Afplicabiuty or Method. — The method can be succeasfully 
used on all optical systems of relatively large aperture and short 
enco^h focus to permit the plate to be placed sufficiently near the 
focus to obtain strong light, and still separate the discs a measur- 
able diotanoe. The diametor must be large enough to obtetn several 
zones without crowding the holes in the screen too close togetlier. 
Sooh lens systems are photographic lenses, short-focus telescope 
objectives, etc. 

The method has been used on complete instruments, snoh as tele- 
scopes. In a complote telescope the consideration for a tbeoreti- 




Fi(. la- Method spplied to oomplete t«lea(^pe. 

cally perfect image requires the rays to be parallel on coming out 
of tha eyepiece. In general, they will not all be parallel, but some 
will iotetMOt the axis at some point behind the exit pupil. If we 
taka two shadowgraphs, one near the exit pupil and one soma dis- 
tanca behind it, we can obtain the i n fcfta ct ions of tha rays with 
the axis. 



It.t 



I 



K 



ill 



I- 



t 



i 



7t-W9sa 



5 



^tm -J « >.»■■ -A S + Jaa -J 
Fio. IX. — Pkoteynfkic amathgmat Um 




VSSS|t» 



-7 
— \ 





* 4.Mia -J S *Jmm-J * +jm 
Flo. ll.—Pktlofnfluc aniltftmat fau 



jie.e 



r- 



i.t 



S4 



~ -». Vj 



S.0 



Mj 


\^^ 




>< 


».!» 




Xi 


jWf" 






flMM 




\ 


t 




V> 


'. 




y 


:^. 




V 


s> 












\,'\ 






^ 


t 




\ 












\i 








1 
t 




V 

t 





t-Jmm -«JS « ^-Jaai -0.2S « *.^ 
Fig \i.—l'l>«lefrtplHc aiuitijmt Unt 



h 



K 



'-. 



XcVQjUi 



t: 



vs»eim 



^ 



^^ 



V*?"'"^ 



-J s 4.jBa -OJS .fjaa -J • 4^jan -j 
FlO. 14. — Pkotograpku: anaiUtrmat Unj 

apheririal abetraiioo 
Hine coodittea 



186 



THE BRITISH JOCRNAL OF PHOTOGRAPHY 



[Maich 15, 1918. 



Let S, and It. (Fig. 10) be two rays intersecting the axis at 
liistancos \\ and I', from the rear principal plan? of ithe iiistni- 
nu-nt. Tlien {', and U.. will be such distances that 
I I I 



1 



where t is the acconunodation u.'^ed by the obsciver. 
II II 



U, U, 



r-. F. 






The quantity— ( -. — . ) represents tl^e range of accommodation 

tho eye has to assume simultaneously in focussing the rays from 
the instrument on the retina. Since this iS" independent of /, we 



I?.? 



\<JjSm<> 



\ 



>r«T5mt 



:) 



H\ 



>-»SOli.|i 



vyOMM. 






+.Smm —.5 +.Snun —.5 -f .Smm —.5 

Fig. 15. — Photographic anastigmat lens 



r.-lf 


-%i*35Mu 




>.*! 


5(1^ 




■x-sso»» 




M 


50»>i 




|s.o 




,- 




V, 






N.', 






\\ 






f" 

Im 




*r^ 


V 


N 


\ 




^ 


^ 




\ 


^ 








V 






\\ 






\ 






>N 



■^JS +.5min +1.0 — O.ZSO +.Sm]n —.5 rf.5mm —J +^iiua 
Fig. 16. — Old type Rectiknear lens 



"Slum 



)f42 


u''^ 




■X-475/1.U. 




>.S30uM 




>.( 


tOO-M 




{ 


^ 




c 






c 






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\ 


^~ 


N^ 


X 


x~ 


"N. 


\ 


X 






./\ 








X 






^; 






^ 



-.5 e -f Jmm —J +Sam -.5 +Jimn -J o +Jnun 
Fio. 17. — Photograplttcatuuligmat lens 



>« 


Sjut 


K 


/ 


<<-' 










^ 


, . 






\ * 






\ / 






11. s 

I 

-UlO.O 



S 5.0 

i 

■^^ 0.0 

-.5 +.Smni -.5 -t-.Sinin —.5 +.5oim —.5 +.imin. 
Fig. i8. — Photographic anastigmai Itns 

Spherical aberration - — , , _ 

Bine coiluitinn 

-i"i thai it doe.s not depend on the observer's eye, nor on the 
.unount of accommodation he requires in using the telescope, nor 
vhcther the telescope is focussed on a near object or a distant 
iiject, but depends only on the difference in power of tJlie vario«i8 
/mas. ' 

6. Illostbative Descrution of a Set or Curves. — To illus- 
irato l!in meaning of a set of curves, let us take the lens repre- 
sented by Fig. 25. This ip a foreign-made projection lens of the 
I'etzval type for mobion-pioture projection work. A glance 'at 
: lie curves shows that the lens is best corrected im that region of 



the spectrum between 475,n;i and 550;</(, or between the yellow-greeB 
and the 'blue. ' Here the dotted curve and the fnll almost coincide, 
showing freedom from coma near <ihe axis. At abont 13 mm. out 
from the lens centre the curves show appreciable saparaition. This 

corresponds to an aperture 1 : 3.9 (- ■To']- At this apcr 

ture tlie maximum value of AE-AV is 0.09 mm. for 'Wttve length 
550/1/1, and 0.05 mm. for wave length 475ii/i (disrega,rding the centre 
zone of the lens) ; for wave length 425,«h, or the violet, the spherical 
is piaotioally zero, but Iho two curves do not fit so closely, AK — AV 
becoming equal to 0.15 mm. T'his is quite small, tont it is three 
times that of wave length 476/i/i and twice that of wave length 
550/i/<. 

This lens being designed for projection work, the colour con-ec- 
tion should ibe between the red and the blue — that is. the red and 
the blue would focus in the same jwint and the others not far 
away, with no attention paid to the extreme violet. The ilistance- 





V*3Sa*. 




>.475»M 




>. 550 tt>i 




>• 850)11. 


"a 

^10.0 
>1 7..^ 


~"^ 






il 






\ 






\ 






\ 




■\ 






1 










1 

E s.o 


\ 








\ 






\ 






\, 


1. 

1" 

«4 O.p 










1 






) 






V 




1 






f 






/ 






\ 



-A 4-.Sinfii -.5 +.5iuffl —.5 +4oim -^ \ +Jsun. 
Fig. 19. — Projection lens 



•VI12.6 

_^10.0 
§7.5 

ji: 5.0 



"=» 0.0 



V«5,u>i 





1 1 




/ 








V 

'1 


/■ 


t 







V475^H 



^-ii'hl- 



•\.m^^ 



'i 


1 
1 





























/ 









-J 4-^nmi —.5 +.3mm —.5 
Fig. so. — Projection fen* 



^TiTn 


^■«5,x^^ 














^ 10.0 






\ 




K.. 




■J 




... 




\ 


I 
1 






1 


<5 0.0 









V475BJI 



V550^,t 





"MM MM 




» 












'\ 








\ 






\ 









.5 -i-.Siimi —.5 
Fig. 21. — Projection tens 



i — 5 +.lnun 



Spherical aberration. 
Sine condition 



of the full line from the axis {the zero line) gives the amount of 
colour aberration for the particulaa- colour. The average distances 
of the four colours from the axis, using the mean of the red, yellow- 
green, and the 'blue as zero, are as follows : — Violet, —0.18 mm. ; 
blue, —0.13 mm.; yellow-gi'een, 0.00 mm.; and red, -f 0.22 mm. 
This sihows the red' to be far out of achromatism, a£ it foousse* 
0.35 mm. and 0.40 mm. behind the blue and violet respectively. 
The progression of the curves in the same direction (—0.18 mm. to 
+ 0.22 mm.) shows that mo two colours focus at the same point, 
hence there 's no colour correction. 



I 



M»*^ 15, IfilS.] 

i.>e dwterc of the dot*-' 

■ imUuii >' thf E. F. U. 
•. r of tiiv linage with the ^.i.v^ 
I .^4e av«nge diatanow for ectch 
18 mm. b'iur. -0.13 mm.; 
i +0.2S m3i. : that ic, t>y? r-<< 
;. Hi tij" TwJet. with the ji)t«« "ji 
fl I.I.' tiyt- iniac'i iTjjxted by thi 
- i<i« and violM on the ioaide. I : 
vlvaatage with * colour M-rren. m 
iteelf ; bat the only oolnar for . 
btae. Mid tiler* U no rtal a<) 



THK BRITISH JOCRXAL OF PHOTOGRAPHY. 



127 



ixif ahowK the 

variation of the ( 

'-hmtDatiion. 

s :— Viol««. 

. -r f uu nun. ; and 

- 0.4 per cent, big^r 

met in betiw«en. 

I fringes on the 

ipiis ixnnd be better oaed 

t-h coloar is well corrected 

" variation ia Hiiall is 

. as deAaed eariier in 



'.'C other iM* o( c«rT<« fqniith »'inilar iaformaVinn rtcanliqg 




rr* 


i — 

1 



l^t^tp-klAaje. 




-^ 



7?- 



%rA 



PiO. ti—Pn/mtm^ (mm 




I ' " tollnwiuc rii 
•' <prai itMow Fi(«. 11 to I 



Fi^. 19 to 26 are pivtjei-tion leniett of the Petnal type.' The 
curves are not amoaih aiid re^^ar, showing less aare iii snrfacing 
thai'i in tlw photograptiic objectives. The lensea reprt>sented by 
FigB. 19 to 23 were made in tJhis country, the ethen being im- 
ported. It will be seen that our (Unirted Stated) domestic len«ee 
compare faTourably with f<>ri-igu oneA. Fij;s. 24 aad 26 i^ow. con- 
■iderdble coma. All the lcn.«es of this ^roup are of rather largo 
aperture, the largest bein; /,'2 7 approximat<>ly. 

Fig. 27 is a telescope objective (aperture //3.3) made by Zei».s. 
The lens ia txceediogly well corrected for wave len^h 5S0/i/i, which 
is the brightest yellow rr^'ion of tlie ."pectrum, with tlie red and 
tbs bine not far away. The violet has bt^en entirely neglected. 
This ia also true of the colnur correction of the projection lenses, 
as thev all have to be used for risoal work. 



-<» - » • 



•4s* nsliilss ... 

'^■' Ummb, allovui^ .- s -und wtiows m t» the beat 

Ism •■ far ■• the cMttr* wf the Md is r vuKmtu m k . 

CI ■ 



-vea. 

' gruu^ of Vnmm al 
<iaa tjfaa of photo- 
"•lliiy, shaviag good 

iiifb-grads make. 

. i1« .-krf> iui flgaall 
rK-ti- 



^1 



»». ^Hbv- 



'I- '■p/'/t 



>.»5CMit 



X-«50«.>> 











1 






\ 






\ 






u 






V 





Flo. ti>-PnJK*i»n tnu 
v«r»« « vue»» 




^ u m ni a r y 

m wlii«h af(«-t «li» defiiiili'-n i.f a Uiie arp dii<«ns.'-<-d 

llir eenlml ciTors «io- 
. •' •TTTiB vtir \hv axis is 

reTit 
, . . , fx-r 

,. .,11 Um* 4iit|KiU*iil tfntt.ij 

,,, II of tiM' M{IIIVuloilt fii.tl 

Irngth, axmi a' I'lii. The ..)>i>ar,U-uii ami the 

|>r««date are <ii 'iriKV nf the adjuitUiiunt* and 

nieasursnieiitA d>sctuae<i ih« method i> aprpUoabla (o all systems 

I Finl bnsclM onl i>; J Pr»<«l In IMO tl >• J>-writ«~l in nil iHxiki 
• m opticiU inktruiitenf*. 



128 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[Mardi IS, 1918. 



of relatively short focus and large aperture, such as photographic 
lonseg, projection lenses, and telescope objectives, and also to com- 
plete optical syst«n:s. The results of the method as applied to a 
complete t«lesoope are discussed, and are shown to be independent 
of the accommodation of the observer. Seventeen sets of curves 
for us many different lenses are given and an illustrative discussion 
of one set of curves, together \vith a general description of the 
tvpea of lenses represented by each group of cui-ves. 

E. D. Trr.LVEK. 

H. I. Shot-tz. 



neu) materlaiSt^c 



Palladiotype (Matt Surface) Printing Paper. Made by the 
Platinotype Company, 66, Beckenham Road, Penge, 
London, S.E.20. 

Hakkbs of pliotographic portraits will welcome the issue of a 
further variety of Palladiotype pajwr — namely, one with a natural 
surface and yielding prints of brown colour, as distinguished 
from the original issue, with its semi-glossy surface and black 
" colour." Now that platinum is almost unobtainable for pur- 
poses not directly connected with munitions of war, photographers 
will surely be grateful to the Platinotype Company for the scientific 
akili with which they have produced a printing material which 
in its effects — and we believe also in the permanence of its results — 
is able to rank on an equality with Platinotype. The surface ot 
the new grade of Palladiotype is an exceedingly pleasing one, a 
close match to that of the natural surface of the paper itself. The 
colour of the prints — a brown, or as some, perhaps, wouli prefer 
to call it, a warm black, others a deep sepia, is also one which goes 
well both with jwrtraits against a dark baokgi-ound and consisting 
for the most part of the low tones and with those in a high key 
in which light draperies against a white ground are the .predomi- 
nant features. 

The manipulation of the paper is of as simple a character as that 
for the original grade ; in fact, is identical with it, except that the 
clearing baths require to be of half strength, by diluting the solu- 
tions prepared according to the original instructions with an equal 
bulk of distilled or boiled water. The solution used as the de- 
veloper may also be diluted in like proportion, and somewhat softer 
results thereby obtained. In dealing with negatives which are 
somewhat on the flat side for this paper, a pleasing degree of con- 
trast may be secui'ed simply by adding a minute quantity of bichro- 
mate of potash to the developer. 

Considerably quicker in printing than cold ibath Platinotype, as 
certain in its results and as free as the latter from the need of long 
washing, Palladiotype paper clearly recommends itself to those who, 
in these days of restricted staff and demands for the highest class 
of print, are sometimes at no little difficulty to satisfy their custo- 
mers. Of the permanence of Palladium prints we have briefly 
apoken above ; while the evidence of time is still wanting, there is 
overy chemical reason to suppose that the image of a Palladium 
print will last as long unimpaired as one obtained on Platinotype 
paper. 

Missing Watch Pocket Cameras. — Messrs. W. Butcher and Sons, 
LtJ., ask us to state that the following cameras are missing, and 
believed to be stolen in transit: — Model VII., Ros.s Homo, No. 
62,777; Model VIII., Velos 6.3, No. 62,118; Model \>II., Velos 6.3, 
No. 62,961 ; Model VI., Aplanat, No. 63,129. The numbers will be 
found engraved in white letters on the back of the cameras. If 
offered to any dealer, will they be good enough to notify the above 
firm at Camera House, Earringdon Avenue, E.C.4. 

The Kontgen Society has recently foimded an annual lecture in 
memory of its first President, the late Professor Silvanus P. 
Thompson. The first " Sylvanus Thompson Memorial Lecture " 
will be delivered by Professor Sir Ernest Rutherford, F.R.S., at the 
next meeting of the society, to be held on Tuesday, April 9, 1918, 
at 8 p.m. The Council will be pleased to welcome all interested, ani 
applications for cards of admission should be made to the hon. secre- 
tary of the society. Dr. S. Russ, Middlesex Hospital, London, W.l. 
Further i)articular3 will be announced in due course. 



meetinss of Societies. 

— • — 

MEETINGS OP SOCIETIES FOB NEXT WEEK. 

BloMUAV, March 18. 

South Loudon Photographic Society. "Chat on Pictorial Photo(raphy." 8. 

Brigden. 
Oewsbdrv Photographic Society. Hmoking Concert. 
City ot London and Cripplegate Photographic Society. "Enlarged Negative 

MakinK-" B. C. Wickisou. 
Bradford Photographic Society. Yorksliire Photographic Union Prints and 

Members' Print Night. 

TuBSDAv, March 19. 
Koyal Photographic Society. " Development: The Practical Side of tlie Matter.'" 

N. E. Luboshe/. „ 

Birmingham Photographic Society. " The Civilisation of the .\ncient Egyptians. 

K. S. Phillips. 
Hanl«y Photographic Society, Y.M.C.A. Members' Nighl. A.W.Harding. 
Sheffield PhotoKiaphic Society. "A Plea for Humour." Yorkshire Photographic 

Union Slides. U. H. Minshall. . , 

Stalyhridge Photoerapliio and Scientific Society. " Elementary Photography of 

Animals and Birds." W. L. P. Wastell. ,_ 

Monklands Photographic Society. " Mounting Prints and Pa»se Partout. ^ 

Coghill. 
Manchester .Vmateur Photographic Society. Council Meeting. 

TmiReDAV, March 21. 
Hull Photographic Society. "Holiday in North Yorkshire." H.Cook. 
Huddersfleld Naturalist and Photographic Society. " ' "" 

Camera—Rvedttle. " E. S. Maples. 
Liverpool Amateur Photographic Association. "The German Destruction of 

Ctjurehts and Architectural Monuments in Belgium and France, 1914-15." J. 

G. Legge. ..,-.. 

Hammersmith {Hampshire House) Photographic Society. "Sonic Curiosities seen 

through the Microscope." G. Ardaseer, F.R.P.S. 
Rodley and District Photographic Society. Members' Night. 



' Here and There with a 



ROYAL PHOTOGRAPHIC SOCIETY. 
Meeting held on Tuesday, MarcJi 12, Dr. G. H. Rodman in the chair. 
A lecture on a convenient accurate photometer for the measure- 
ment of photographic densities, by Messrs. D. E. Benson, W. B. 
Ferguson, and F. F. Renwick, was delivered. Mr. Renwick dealing 
with the evolution and puiposes of the insti'umeut, Mr. Benson with 
its construction, illustrated with diagrams, and Mr. Ferguson with 
its employmeijjr. In the absence of diagrams, much of what was a 
most interesting lecture must be omitted or referred to very briefly. 
In a general way the instrument consists of a dark chamber, 31 in. 
long, 5 or 6 in. high, and 4 or 5 in. broad ; the roof and walls are 
formed by close-fitting velvet curtains running on metal rods, which 
are the angular supports. ITie chamber is supported on a cast 
aluminium base, and can be worked on its longer axis. At the 
right-hand end is the source of light — an electric lamp ; the light 
from this is reflected by mirrors ti'avelling on smooth rods running 
the entire length of the instrument, and is brought to bear upon two 
opal plates. The illumination of these plates is equalised by sliding 
the mirrors to and fro, and in doing so an index travels along a 
scale situated along the front. Care has to be taken t-o adjust things 
.so that before measui-ement is begun the index stands at or near 
zero. The plate to be measured is placed over one of the opal glasses, 
.■ind the mirrors are then slid along till the illumination is again equal, 
when the density of the part nieasui-ed may be read off directly from 
the scale. To facilitate the measurements, a telescope is hinged over 
the plate operated upon, and as this projects horizontally or at a 
suitable angle, the readings are obtained in a way causing the 
minimum of fatigue to the observer. 

Mr. Renwick said 75 per cent, of photographers doubtless won- 
dered why all this Ixjther was taken about photoraetei-s. but tliese 
instruments were to the scientific photographer 'what the balance 
was to the chemist. The usual estimation of densities was altogether 
fallacious, and he hoped the time was not far distant when every 
statement on the subject would be supported by quantitative photo- 
metric data. From time to time articles appeared in the photographic 
press urging readers to make measurements of the kind, aided only 
by such appliances as might be found in the dark room. Mr. Ren- 
wick disagreed with these suggestions; a photometei' of some kind 
was absolutely necessai-y. A useful instrument might be made by 
anyone acquainted with the use of tools, and if the essential parts 
were accurate and worked smoothly, much valuable work might be 
done, although, of course, the precision and delicacy of Mr. Benson's 
handiwork were invaluable for important work. 

The method adopted in the instrument before him was based on 
the law of inverse squares, and, to ensm'e success, the light must be 
sufficiently powerful and under control, and the distances between 
the source of light and the points where the readings were made 



March 15, 1916] 



THE BRITISH JOfRNAl. OF PHOTOGRAPHV. 



129 



must I" - :7ieiit. The «ale nluxilJ 

<)e so I' ~1 together s<i <•!.*<■'.> as 

to be difficult '.t. K-oJ. (Jilt- o: t'.i- oiliest of photonietem was 

th»t de!(i<»n^ l>v Si-hmidt and Ha^ iisch, but it* ef>nstnirtii>n was 

lie power vi' 1.600, it was difficult lo read 

of 2. and n- the readings were maJe wlwii 

' !iy the preosure of bl>M>d 

-red to a considerable 

'Txteiii t«. The source of light 

<-hoaId ■ ■■ s'lch as that uf an oil 

Ump wan kerv ui .. iiulHjit..- • fact that Hiirt«T 

ind DrlfSill Hi. ! ■ w-r.rV: ns had adopted a 

■r bead lamp, 
I was difficult 
. trum 1.5 tu I H, and then only after restinic 
r some time it waa quite poasib'e with the 
new instrument to measure up t<j i!'<m 1.8 to 2.8. and for X-ray 
-A.,,r< i!iat oou'd b^ increftsed much !i:,'her by the use of the Ediswan 
')'-Iight " lamp and some adju.stmcnta o( the instrument. As 
-..c ■ .laga r.""""*«' -• ■• '"■' n>..r.. ■■ .„ .;, Jt «ru possible ti> get 
the current ' ulators, or direct fnim 

the main b^ U .tas * convenience to be 

able to mea- without hs\;ng to cut it up 

into hal' - r« had been made tu obtain 

that Ciii It waa another cuiivruiem-e 

tu be ab.r ui ^n ••■mf-i n'.y in .-| i ii ,.r and look through-a liorixuntal 
tube or to inrlint- the tul>e to any dcafcd angle by rorkinf the 
n;<li .riient on its axis. It was a! ."■'.'.' 'on 

f' >te to lie meAKirnJ ti> wit: in- 

1- »- ' •■:'' '- An Jtti'iniit li.l'l al-'j lieell 

'■■•■■'■ 'I from surfaces as fn.m a phot<>- 

Kraphic pr.iit. 1 - utiil in an et|>erimeiitsl 

stage, bat he hail ' would be su<'ce»ful 

ttensiin thin •:.... \4.i atmction. and his 

f Wfn« -w-.u^^ n*4 ).t riem. 

•nigneil tome yean 

•"II and Ri-nwick 

•ird 

I. lit 

was un]iortant to 

the opal disc dis- 

■ et tb* MID point 

' 1 I ' ' « numltrr i .f (esia, 

^ • I then frnn .Hi, 

■ ! - It » I. lat 

I ' fairly reKnIar; in u- iig 

t^i Ii..' I he choking I' , 1 to 

'■■ ■■ satialactorjr when the con- 

UTS varied in their readings 

—• • • -t'lalities. Mr. Rni 

disiiig the various 



jinot<»nifi4'r 



I uf the 111 

• III <i ruction. 

I 



\T i\"' meeting held oi 

L. ■•■' .vnd Dr. 8. Kuse on •' 

V r^x . I.I ti. r tr 

tnateriala bar* general 

the inct ' -' - ^ are ii.... 
waa Bi I uiare the ' 



^m, ali'i -ll IMi* . ri'l ■'! 

developed. The deiisiU 



i| questions on various points, 
id all cunrurred in rxpi.-ssint! 
• which IiimI lieell rlTeiteil ill 



re read by Ur, f Ii I 
il Hasts for f 

.Mi.U ..I il,.. 

l»t 

I lie 
of 

,pt 
by 

: HI lofiH. 

.t« u)Min 

the 



preliminary invmtigation enables the harmful effectn of the standair 
source of radiation to he determined, and thu« eivea a meaning t- 
ihe indication of the bioloi;ical basis plate. 

Radium forms a useful s<iurce of radi.ition tor practical piu'poc^n- 
after the initial teet« have been ma<le, and it overcoinee difficulti. - 
in the employment of an X-ray tube a« a constant nourc*. 

The effect of hard and soft radiation (12-inoh spark to 2-inrii 
on the photographic plate waa fully inveetijated, and it wiis an 
eluded that for the luinie ionising effect the hard and soft ra> - 
produced about the siuiie photographic effect ; th« effect, howevv 
varies with different makes of plates, and in consequence all con. 
pariions must in practice be made with the wuiio variety. 

"A Mobile -X-ray l"iiit." — Mr. K. ('. Head gave a detailed ili 
s<-riptiuii, illustrated by numerous photograplw. of a motor X-ra\, 
unit recently draignetl juid cuiuitructed for ut<e in Mesopotamia, 
etc. The Austin Chassis was ciioKen on account of its low lo>u{ 
line, and the body was divided into two (lortions, one to serve .i.' 
dark room, while the otlier contained the X-ray equipment. It. 
operation a tent is erected at one side of the oar, with the result 
that it is unnecessary to remove the coil or switchboard for uw. 
Klertric current is supplied from a dynamo run off the motor engir.. 
and fnim a small battery of accumulators, and it, sufficient to r-'iMl. 
possible the production of short-exposure railingraphs. 



ReiDs and Rotes. 

RoTO<iRAVi-8K TidSt'ES. — The .Autoty|)e I'umpany, 74, Xi « 
Oxford Street. I.,ondon, W.C'.l, send us a price-list, just issued, "^ 
the tissues and other materials for rotary photogravure, which in. 
sperMllies of theirs. The list includes some pages of jiracti' .. 
mites on the working of the rotary |ihot<igr»vur« process, ,imo:i. 
which those engaged in this method will find some hints of value. 

Photoohm'HH- MofNTS. — A catalogue of the many description- 
o( mount, amateur and professi.mal, manufa< tured by them has 
just lieeii i»»iied bv .Messrs. W. ButcJier and Sons, Ltd., Camera 
House, Fsrnigdoii .\ venue, lyiuiioii. K.f.4. Il is well iUustratiii 
and list« also many items of miscellac-iiuii photographic stationer) 
such as wtllets for photographs, euvehipes. paase-partout materiali- 
and p<Mtal wrapfwrs. 

Tm« 8r>llr RrroHM The current iwue fi this very practi. ;■ 
monthly journal of X-ray work contains, among other articles, oin 
on the daiigen (and preventives theref<»r) in X ray praclici 
another on the use iif the fluorescent screen. X-ray operators shoui': 
make a point of getting each copy of the '■ Sunic Rircord," as thr\ 
may do without cost by a|>plicalifiii to .Messrs Watsons, 196, '■■'••• 
Portland Strt-et, Uiudon, W.l. 

How TO M»Ki. PoBTlUITs. — A revised and enlarged editimi • 
this little manual, issued by the .\ineri<an Plu)U>gr»]ihi<; I'li' 
lishing Company, 22», Columbus Avenue, Uostun, Maas., has ju^' 
b«>en i»«ued. In noticing previous <Hiilions we have comuient.i 
U|Min ila very | radical instruction in indoor and flaslilght pm 
traiture. The fact that jO,000 copies have now been publish- n 
alUiitrther ;» nitfi< lent tribute to its usefniiiens to the .-imaleur work. 
It is i«-'i.d !ii p:i!»r rovers at 'liS <vnt« : cloth bound, 50 rents. Ii 
mat. t.i the CniteJ States it may bo pointed out tiim 

lj„. , In- that by international 5 cent coupons, obtaii 

able at any |K>sl-o(lice. not by piMtal orders, which are not nngotial'.. 
ill the rnit«'<l .State*. 

lie MANCHKSTta CoLtwiE Or Technolooy. — In order ran. 

i.i.-.piately to denot«' its University rank, the title of the Mai 
I hi-hter iNchntil 4if TiH-hiiology has been chsngiid to "College •' 

re<-hnoli.gy," a name more in accordance with the advance*! ii:it;./. 
of the cours<-s of instruction and with the facilities for i' 
work which are available within its walU. At the prescia -.. 
much reseanh of a confidential character for war purposes is beini 
carried on, and this part of the activity of the College of Tecliiv''- • 
will (>e farther »timulated in the future by tho number of r. 
scholarHhips, of the value of £100 a year each, which arc !■■ 
within the gift of the governing body. It scarcely needs to l" 
rii^alletl that photography and photfi mechanical proceeses constituli 
one of the Faculties of the college, normally uader Uie direction • 



130 



THE BRITISH JOURNAL OF ^HOTOORAPH^ 



[Maioli 15, 1918. 



Mr. Cliarlcg \V. Gamble, for whom, during the period of hi« ser- 
\iec8 ■:< heal n( the photographic .section of the Royal Naval Air 
Sorvire, Mr. R. B. Kishendeii ha« been deputising. 

Imperial \\'.\n Piiotooraphs in Colour.— In our notice last week 
of the exhibition of official war photographs now open at the 
(Vrafton Galleries it should have lieen mentioned that the whole 
of the enlargements constituting the exhibition are tlic production 
lit Messrs. Raines and Co., of Ealing. Messrs. Raines intimate 
that while the chief part of the process employed in the work is 
that of aerograph colouring of sepia-toned prints, other auxiliaries 
to the air-brush work have been employed. The references in some 
of tlie dailj- ne\v«p»pei-g to the exhibition as a demonstration ot 
colour photography may, perhaps, be taken as a compliment by 
Messrs. Raines, but it should, of course, have been clear, even to 
the lay writer, that the exhibits are coloured photographs, and have 
nothing in common with the processes which are oriinarily classcfl 
as colour photography. Kven when the lay writer is at pains to 
lay emphasis upon tlie distinction, he is sometimes guilty of a 
technical howler, as in the case of a Scottish newspaper which 
solemnlj- informs its readers that in the colouring of the prints " the 
pigment is sprayed on the bromide print in the course of print- 
ing " — one of those photographic operations which one would like 
to see illustrated. 

TnK Xatiokal Portrait Gallery. — In the House of Commons on 
March 7, Mr. Bowerman asked the Secretary to the Treasury if he 
is aware that the trustees of the National Portrait Gallery purpose 
commemorating, by a series of permanent photographs, the features 
of distinguished living contemporaries of British nationality, in- 
cluding all person-s, naval, military, or civilian, who, during the 
war, have rendered service to their country by their valour or by 
the promotion of the Empire welfare; whether he is aware that for 
this purpose the trustees have given one firm of photographers a 
monopoly ; and whether, in view of the national character of the 
propo.sed memorial, the trustees will consider the desirability of in- 
cluding photogi-aphs other than those to be taken by the firm so 
chosen?— Mr. Baldwin : The answer to the first part of the questio.T 
is in the affirmative ; to the second, that the employment of a par- 
ticular firm for tliis purpose is not a monopoly, since photographs by 
other photographers are accepted under certain conditions ; and to 
the third, that the trustees have always accepted photographs taken 
by any photographer of persons living or deceased who have the 
.slightest claim to distinction in any sphere of life. In no circum- 
stances are photographs taken from life exhibited in the Galleries ; 
they are acquired solely for reference purposes. 

New- Military Prohibition of Photography.— The order whicli 
came into force last Tveek provides that no person without 
special ppi-mission may make any photograph, sketch, plan, model, 
or other representation of any place or thing within the following 
arcis : — 

Metropd'tlan Police Dy'lrirt.— AW places (except urban districts 
of Erith and Bexley and parish of Crayford) which are outside a 
radius of twelve miles from Charing Cross Railway Station. 

^»!.»fj-.— Municipal borovigh of Chelmsford ; urban districts of 
Epping, Romford, Brentwood, and Grays; parts of rural districts 
of Epping and Romford not included in Metropolitan Police District, 
rural districts of Ongar and Billericay, and part of rural district of 
Orsett, not included in Thames and Medway area ; parishes of Rox- 
well, Writtlo, Witford, Ingatestone and Fryering, Margaretting 
Stock. Buttsbnrj-, Great Baddow, West Hanningfield, South Han- 
ningfield, Runwell, Rawreth, Rayleigh, Thundersley, South Benfleet, 
Hadleigh, and Canvey Island. 

A>n^— Urban districts of Dartford. Sevenoaks, and Wrotham ; 
rural district* of Dartford (except parish of Crayford), part of rural 
district of Bromley not included in Metropolitan Police District, and 
rural district of Mailing (except parishes of East Peckham, Would- 
ham, Burham, Aylesford, and Allington) ; parishes of Halstead, Shore- 
ham, Westerham, Brastcd, Sundridge, Chevening, Dunton Green, 
Riverhead, Sevenoaks, Weald, Otford. Kemsing, and Seal. 

Svrreg. — Urban districts of Iieatherhead and Caterham ; parishes 
«jf Ashtead. Headley, Mickleham, Walton-on-the-Hill, Kingswood, 
Chipsteiwl, Gatton, Merstham, and Clmlden; and part of rural dis- 
trict of Crt)d.stone lying north of Redhill and Tonbridge branch of 
South-Eastern and Chatham Railwav. 



Within the Metroi)olitan area the regulations prohibiting the 
photographing, etc., of objects of military interest and importance, 
of course, still hold good. 

Persons who desire permission, however, Twill have no difficulty 
in obtaining it, either to make sketches or take photographs, oni 
applying to Hea<lquarters. London District, Horse Guards Annexe, 
12. Ciiilton House Terrace, W.C.2. 

Harde.sino Ar.ENTs and GiXATiNE. — Equi valent amounts of potash 
alum and aluminium sulphate exert the same hardening action on 
gelatine, two parts by weight of aluminium sulphate being equiva- 
lent to three parts by weight of potash alum. Commercially pure 
aluminium sulphate is satisfactoi-y if this does not contain too much 
iron, though if the sample is at all acid the solution should bo 
neutralised by adding ammonia until a faint permanent precipitate 
is obtained. When mixing the usual liquid hardener formula with 
commercial aluminiimi sulphate a slight milky suspension is formed^ 
but this is harmless and settles out on standing. 

The hardening action of potash and ammonium alum on gelatine haa 
been measured by comparing the degree of swelling and the change 
in melting-point of gelatine films treated with solutions of the two 
salts. No difference was observed between ammonium alum ani 
potash alum in their hardening action when substituted weight for 
weight in the usual hardening formula. In practice, if any differ- 
en.'e in hardening action occurs, this is due to the use of an imptiro 
ammonium alum, in which case, providing the impurities are harm- 
less, an increased amount of ammonium alum should be used to such 
an extent that its content of aluminium sulphate is the same as that^ 
in the potash alum called for by the particular formula. When 
using ammonium alum, if the fixing bath becomes alkaline by virtue- 
of a neutralisation of the acid by the developer carried over, 
ammonia will be liberated, resulting in the production ot dichroic 
fog and stain. No trouble will be experienced, however, if care bo 
taken to keep the bath acid. — Eastman Kodak Laboratory Reports,. 

443 and 444. 

^ 

Correspondence* 

— • — 

'-• Correspondents should never write on both sides o/ the paper. No 
notice is taken of communicatiojis unless the names and addresi,ei' 
of the writers are given. 
".* We do not U7uJertake responsibility for the oj/i/nions expressed bff- 
our corresvondrnts. ' 

DEVELOPER FOR PROCESS WORK. 
To the Editors. 
Gentlemen, — I cannot allow Mr. Pfenninger's letter to pass with- 
out comment. He states that the substitute for acetic acid and 
methylated spirit which I gave in the " B.J. ." November 30,1917, 
has been found wanting in his hands. I can only say that at Bolt 
Coui-t School, and in several trade houses, it works quite well. 
Sometimes the gelatine becomes slightly coagulated, and then the- 
bottle requires shaking. May I point out that the developer sug- 
gested by Mr. Pfenninger contains acetic acid, and it is the use of 
this substance which is the present difficulty. — Youfs faithfully, 

W. J. Smith. 
L.C.C. School of Photo-Engravmg, Bolt Court, Fleet Street, E.G. 



SOFT WATER AND BLISTERS. 
To the Editors. 
Gentlemen, —Your paragraph in this week's issue on the relative 
action of a hard and soft water supply in causing blisters on bromide 
prints interested me, as my experience fully substantiates your 
theory. Living in North Wales, where the water supply — derived, 
from one of the Welsh lakes — was extremely soft, I was very much 
troubled with blisters in sulphide sepia toning. The least varia- 
tion in temperature during this process covered the prints with 
minute blisters, and with the most careful attention it was difficult 
to escape without some. Two years ago I removed to Lancashire, 
and the town supply of water is just the reverse — extremely hard. 
During this time — winter and summer, hot and cold weather — I 
have toned, on an average, fifty dozen postcards daily, and I have not 
had a single blister. I have not the least hesitation in attributing 
this to the bander water. — Yours faithfuUv, H. I. E. 



M.iro': 16. l»io 



BRITISH 



1\.^ .\1. 



.i<ArH\ 



THE COVERS 

T 
^ that u pr 'l 
\>e«n i>ut !'■ : 
. .A of Photu;;ni|>li\ 
: t '.■..* «bould l>o taken i i 
'l to the area illumuistv<l . 
^.- two obj^^^tmiis to such 



'R OF A LENS. 

■re. 
I ahoold be ma<l>- ai::tiii;-t the 
Aard in reciiit U.-i]<-< "i the 

that the jilini-*.- ■coverinK 
refer to oonit- iiti;r><' of deflni- 

ik limitation of the ni«wiiii|; of 



' ' rst objeiUon (qu • nt in it»elfl i« 

■ ••: with fart. A ■'•» »n area on 

• w* ail uuaKe which can I 1 ou a photoi;raphic 

: ia the fact. To «uiy •' •ovfre n field over 

!(la an unaj>ecifit<d <!• 'I- .\ny- 

;iie word "cover" v -liould at 

leaat be bound to specify the : i Ued. and 

than tint degree of definition .'-' > general 

■tccaptanoe. Failare to cotnply with theae> conditions conAitutea 

' h« aecond objectioii. 

Ti y exeuae thai I can •■• 

cu\.!ii:^ (lower " with regard t 
lion, ii that aome makara hava »> iiM-d it. 



•• uae of the word* 

~!ead of ti> illuniina- 

But I am not awiire 



l)i!if th»-r<» Vi.it an 



■r..rnn>nt a* to what 
;.t, or iwttiafac 



1 1 don't 



.l.T 



.,f 



ijat»-4 11.1%*.' i><-«'ii in.t'ic 



iltTiiiitiitii wiM 

waa iii- 

,.:'.' unaatia- 

ype and iHillo- 

r- ..._•« i»«l aa 

>• are not 

>• ctaaard 

ry whola 

ret«r aiwl 



local length waa marked aa half 
II > ..-v doubtful i' 
. I l« found. 



V lUi the tablea pr>jlM*iii^ 
.isrta an ia loeaa, a leoa ! 
•T • plats of any dimmaii - 
>' tually covert, and pmun. 
k larsa pUt«. 

'-nme back to the baaic (t>t A lana cnvera 
'loeaa • photographic iniaga. — Your* 



f 



riefini- 

.i) on 
'and 

lice. 



,r.l, 
i»rr. 



HYPO 

T 
Ocntlemen, — Perhapa y>". 



l!Ki OVERY. 



I<> la 



agree wilU Mr. I'l^-.r m IkjIU tii'-?e c<ioclu«i<^ns I 

1. If a aolutinn of a haloid lu' ' ' ' 

mode in hypo until tha laUer i- 
tremtad aa I !, the ti\ ) 



t me trcapoaa 



'ii> 



Further 

|>hal«< 

otthe 

2. I' 



. ti. 



r«iq)ond> i'i 
I ealeut 



rt-^auia ita 
all tha aaoal 



<aiiM <ut«ut aa wbco the 
. hen ammonia ia added to 



hxili^ tjualltir*. 

ttata for thi<i«iil' 
axactly mjuuI to that 



ted aa the •ulphi<)e, and 
i;a<n rmtored, altliongh not 
' added, 
.tion and no precipitation 



but it is difficult to estiniitte the exact quantity required, itnii an . 
e.xcv8« would form sojiuiu sulphide. 

I am still experimenting, and although I have separated the fii 
product of my process, 1 have bad no time completely to ascert.T 
ita compnaitton, except so far aa to prove that it is certainly a th: 
sulphate. 

I am looking forward with great iutereat to the publication nf the 
reanlts of Mr. Piper's experiment*, for even if his reeulte arn 
negative one«, as I gather from bis letter that thfy are, they ni.. 
help someone else in ehieidatimg the problem. — Yours faithfully. 

L. F. E. JoBKilON. 

9 rfii'lil.iiry Cruiige. London, N.. March 11. 



>iortad to, it aeenn to hava ver^ littla effect upon 



I think Mr. Piper will find tli.kt roodam cheniata are agreed 

that when a silver hatolH ii <h.v - H in hypo a dcmUa tJuoaulpbate 

"f Oliver and sodiom is ionvl. >-tted hydrogaa ia added 

to this double sa!'. <!-. .r i< I. and a eorreapondinK 

amount of the n being umtable. at 

• >ri< e splita up II 'le. My object in 

; aoiaKiliia waa to rrpUc ' ' <) aJver, and thus 

. I decomooaition. Prob.iblv .'- would be better. 



T.\NK DEVELOPMENT. 
To the Editors. 
Oentlemeii, — There seems to bo a great diversity of opinion ;>- 
to the m«rit« or demerits of the tank in development, and I aboultl 
be glad to know the opinions of brother " proa. " aa to their 
exi>eriei>ce». Personally, I have used it for a long lime past, and 
have given it a giviJ test, and am in favour of it, but I have met 
several tJuit are just the other way against it. Mr. H. Essenhigb- 
forke. ill this town, is in favour of it, I know, and I am indebted 
to him for several hints that have lieeii of use in many ways. But. 
as I have said, there seems to be a great di(Tt*reiice of opinion, an.l 
I should hke to heor the views of others if they will write to the 
" B .f " n;H you wll be kind enough to publish thoni, aa wu are 
nii: old U< leani — at least, I am not. I know. I am quite 

s»! t i' a .-r.-at time saver, as, previous to adopting it, I 

spent many >, plates, ^uid the time is now put in in 

dt> nu ■■thiT f ,;i-s are developing. Now, by that I do 

ii.Jt mean Ihiil I put my plates into the tank and remove tliem at the 
end o( :. jx-riod of time, ii.i matter what the result. I put them into 
the tmik. carefully noting the time, and at the end of tlie tirst few 
minutr* — say, five> — I go and turn the plates over, not Uio tank, 
whi<'ii I ciMild easily do, as I use a small one, and so on till they are 
fiiii>hed or till I have gi>t the result that I want. J use Johnson's 
'■ .\m>1," aa I find that I can get on better with that than pyro.,Bnd 
I do not thniw away the develi>|ier after each botch, but put it by 
till next wanted, then bring it up to the capacity of the tank, whitji 
ia 33 Ml. in a I pi., and add 1 dr. Aaol.and go again. I find that 
titia works quite well, aa I tliiiik it is better aa the .lovoloper gets 
" riper," shall we s« v 7 I might odd that I always note the tem- 
perature with a thermometer before I begiu/a» 1 do not think that 
well if it is hotter than 70. Anotlier P ' 

II a measure, and if you add fresh fron 
'.' < 11 vkith the old ; nut add a little to the tan.; jii>t 
atv put in, or you.will have trouble with marked 
[> — one to which I am indebted to Mr. '" 
per into t'he tank to (x>ver the first pair m 
.\.> t!o t inw 11,(1 I use V ■ ' iHiir of plates tuick Ui boik.ijlac 

ing the lank into a fa' ii, 1 dntp each l>uir of plates into 

tlo < until all aic in. Do not put your plate.H inix) tank 

fifi ir on the developer, or you will have a splendid crofi 

of air bills. The re.i-on for tJie dish is obvious, as Jevi'Io[>er will 
fliHv over, and would bo otherwise lost if the tank was stond in the 
sink. No doubt a giml many will say that it is not much save of 
time if you turn over the plates at the end of five minutes, but, if 
you think, you can alick on a grajd majiy tissues, for in- 
stance, in Ave minutra, and if you run a one-man show, 
as I do, these five minntea are of value. Of coorae, 
when your pistes are developed you will put them into 
"" ftfca^ypo. l)o not by any chance get your tanks near the fi-xer ; have 
anothir t-ink quite away. Inae a woodeh one and n feoantc rock, 
wh t get near the developer by any chance. I think th«t 

I Ii I 'iii>d my method of working, nnd I have no doubt that 

I ahail be told that it is all very well for me using a r.mall lank. Uf 
I have only a small quantity of platea, but I have several, an J I 
fre<|u>-iitly have them all going at the time, and if I find that I have 
suffirieot expoaed platea to fill the tank in a brief interval, I start 
the tank going in the middle of the day; but— a warning — do n^t 
go away and forget it, and then blame the tank. Of course, it is 
best, if |M>ssible, to expose the plates accurately, but I think thai 
I err on the side of full, mthcr than iincler invnelf. — Yours faith 
fully, W. Bri;ntok. 

Hevenoaks. 



It sr«'m» * 

mix the 

see tiist It III! -v>' 
liefore llie plsli' 



( 

i 



132 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[March 15, 1918. 



Jlnsioers fo Corresponacnts. 

• — 

SPECIAL NOTICE. 
/n consequence of general reduced supplies of paper, as the result 
of prohibition of the importatio n of much wood pulp and grass, 
a tnuMer space will he available until further notice for replies 
to correspondents. 

Moreover, vie will answer by post if stamped and addressed ^nve- 
tope is enclosed for reply: S-cent International Coupon, from 
readers abroad. 

The full questions and answers will be printed only in the case of 
inquiries of genertd interest. 

Queries to be answered in the Friday's " Journal. " must reach us 
not later than Tuesday (posted Monday), and s hould be 
addressed to the Editors. 

L. .\ND Co. — It is most likely that tlie balsam has deteriorated. If 
you will send the lens to us we would report on it. If the surfaces 
require repolishing, we are afraid you will have to wait until after 
the war, since few opticians can undertake any photographic work 
at present. 
H. G. R. — There i« no objection to fixing prints developed by metol 
and amidol in the same bath. As a matter of fact, we have fixed 
prints made by different developers simultaneously. 2. You should 
use varnish or mediiun on uranium intensified prints to protect 
them from the atmosphere ; try gently rubbing with a little turpen- 
tine to remove the tarnish and then varnish. 3. We do not think the 
price too high for the enlargements of good quality. 
H. T. B.— The list price of the Dallmeyer 4B lens is £38 ; that of 
the Busch No. 3 lens. £3 3s. ; and the No. 4 lens, £4 4s. You 
should get from one-half to two-thirds these prices. You can 
either sell them by auction at Stevens's Auction Rooms, King 
Street, Covent Garden, where there is a photographic apparatus 
sale every Friday, or you can advertise them in the columns of the 
" B.J,." in which case you can avail yourself of our deposit system. 
Lens for LXrge He.ad.— In my studio, which is 22 ft. by 15 ft., I 
use a, triple extension lialf-plate camera with an 8 in. focus, by 
which I get suitable photographs for P.C. and half-plate, but i 
want to be able to take larger heads. What focus would you 
recommend ? I thought of having a R.R. of about 12 in. ,or 14 in. 
focus. Would this.be suitable? — ^F. N. 

Presuming your camera has an extension of 20 in., you can use 
a 12-in. lens for a head half size or any lesser scale of reproduc- 
tion. Apparently this is as long a focus as your camera will take, 
and it is a fairly decent length of focus for large heads. 
Focal Length and Apeeture.— I have recently purchased 
.several second-hand lenses. As far as I can see by actual trial, 
there appears to be some alteration of focus with each stop used, 
so that when focussing at, say, f/16, on altering to /■/22, the focus 
■ lianges also, and so on for every different stop. Could you 
nform me if there is any optical rule or equation relating to focus 
and nodal points which would give me, by calculation, the amount 
■f alteration required as a definite quantity, so that the lens 
mount could be marked with the difference, and so save the con- 
tinuous trouble of refocussing? — H. Lees. 

ITiis sometimes occurs, but we would not have e.xpected it to 
have any serious effect with the lenses you mention. It is direct 
•iberration, and there is no rule by which you can calculate the 
\ariat;on. Nothing but trial will enable you to make the desired 
correction. The usual remedy is to focus with the stop that is 
to be used. 

T.i.ue-Print Pai-er.— I have twenty rolls of ferro-prussiato paper 
i.jr printing from tracings, but it is apparently old stock. With 
..i-dinary methods, a minute's printing in sun, then treated in 
■vater bath, no results are obtainable ; but by printing foi- fifteen 
minutes dark-blue lines appear on a pale-green ground. This 
would not do for purpose required. Is there any solution I could 
fix them in so that this image would remain fairly permanent? I 
have tried development with polass-ferricyanide and fixing in 



sulphuric acid, but results are not satisfactory. As a professional 
who values vour kindly advice, I should be pleased if you could 
guide me in this matter.— "Ferbo-Reussiate." 

We are afraid that the paper has gone too far for any treatment 
to be effective. If you cannot replace it, you might utilise it by 
sensitising the back, which you can easily do with a sponge, if 
you have no dishes large enough. A simple formula is : — 

A. Ferric ammonium citrate 400 grs. 

Water 5 ozs. 

B. Potass ferricyanide 300 grs. 

Water 6 ozs. 

Mix, filter, and keep in the dark. The paper will keep better if 
i gr. of potass bichromate is added to each ounce of mixed solution. 

Aero Fixing Bath, etc. — 1. Wo have been using acetic acid in 
fixing baths, but cannot get it any longer. Will sulphuric acid do 
in its p!a<!e? 2. Can yon tell us of anything that will take ihe 
place of methylated spirits for cleaning cards, etc. ? 3. Can you 
give formula for making a glass roof dull, instead of using tissue 
ipapor for keeping sun out? 

1. You can use sulphuric acid in the following way :■ — 
Add- 
Strong suli>huric acid 2dr. fl. 

Water .' 2ozs. 

Ul — 

Sodium sujphite 2 ozs. 

Water 6ozs. 

And pour the mixture into— 

Hypo 16 ozs. 

Water' 48 ozs. 

Finally add to the above mixture — 

Chrome, alum loz. 

Water 8ozs. 

2. Petrol or benzol will anawer, or a weak ferricyanide and 
hjTK) reducer may be applied with cotton-wool before the final 
washing. 

3. Zinc white ground in oil and thinned with tui-pentine, 
stippled on with a nearly dry brush, or ordinary stardi as used 
for mounting mixed with common whiting. 

'^\jt IBnttalj lirantal td ^hata^a^ljii. 

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THE BRITISH 



JOURNAL OP PHOTOGEAPHT. 



3020. Vol. LXV. 



FRIDAY, MARCH 22, 1918. 



Pmce Twopence. 



Contents. 



WtMU 

U5 

LnuTB Rmovcnom, Caao- 
' uca InTnniricATioa um 

U>Aai«ii Tan!i<i Itt 

' ' lu Minos Pannmn w Pbvto- 
>mAm. By C. H. BrUMaliy. . 1)5 
!■ Paovs^uioiui, PaoTooaAnoo 

AlMCUTlOII IJ7 

Rat Mornon Picrvmss la 

(oTOAaftFBic IxvcvrmTOrOBaAV 
HartAts m 

■• •»• V < ' . ;- ..f -.iiiM ASS nn 
k'iij:j'stm .)i. ii:*iMaMB ...... UB 



A... •!»»«■ Normi 1*) 

OiviauciAL un> Lsoal IvtBIxi- 

O""-! 140 

PirixT H>«« 141 

MtnTCT— or Hiiniiini 141 

Ni«« Ajra RoTsa 142 

Ooaaaavonuica :— 
aeft Wuar u>d Bllttan Hn» 
Baootwy — Tbo Co<r<>riii( 
PowOTol* tiwu— RacoTery of 
MilTar timn Spsal FUtoc 
BMh» 145 

*»»W»M ID OmIIMI «■■■■■ . . . . 144 



SDIOIABY. 

Wilt ttmdtr* of lint adt«rtit»mmtU Undlg give a tart/ul rtading 
, ,L. :p-apA on lAu pag« aad to (he Mticc prittUd at Uu fact 



' ■' T-aUlTavlur LMtar« by Mr. C. H 
■ of int«nalfyin( «im1 toning with 
.. ...A aiutyaia «l the prooM*, pomta out 
' ooodaoting it ia two itaH, or otm in 
••rncyvaid* itaaH can l>« dwDfr.nrJ with 
•t M— ehed to a <r 
.nd aabiMajiMatly «r. 

■in.lafot blue tone*, (i*. Lis.) 

o P riA niopal Photographers' 

-Ti%a waa lonnally JlocUd 

tha nonibar of •obtenp- 

— ,. . vad ia ooa yaar «naa tba 

Aaotbar aaaaanoMMat wm that tba 

raaoltad in ill* ditcoa tu ioaiioa o( th« 

ol phutij^^yiit lu the Prca* by th« Royal Flying Corp*. 

~ vo tona of waahinj t-in'r; for print* is d..* 
Aaiiataiita' Notea." Trinta are lYUKtai.' 

• - ''Ut tha tripla cocwtructioo of the tank KoiKjnm.'i 

' and facilitataa tha ayit«a>atic traiMfar of printa tnm OBa 
^aUr to aaothar. (P. 140.) 
Maaart. Johnaoo and Son*' Sinellifi< Worki. T 
It that in Ihair •xperiaoca livar uf >:il|>bur lo 

'owing down tha whola of tha ailver irom apeuw lixuu bath* 
^ooa daKriptkm. (P. 143.) 

loataoca of tha ditapp««ranc« <<t tha btiatcr trouble, conaa- 
' apon Iha artiflcial haManinc of th« watar^aoppiy, ii cited by 
-apoodenl. (P. 143.) 
Aodjoma volama daaiing with the davalopaaant and preeeot 
/~t n! ih» Britiah pbotocraphi'- uidaatry na* >""" ■— "■■'-i 
Pbolographie jiaonf.Ktar«n' AaK^< 
-nportaot bay«r> aiKl ImportCTa wiii 
' >rHKn ooontriM. (P. l.VI ) 
•nmmnred that the pnohibitioa of tha azpott of 
:-tpen from KrAOca to Allied or nentral 
irswn ej(' 'it aa regards Switzerland. 

roodeot diapntea the utility and, indeed, tha poaaibility 
r>>* meaning for the term " oovwing pcrwer " aa aptilieil 
"d Uat waek by Mr. W. E. Dabenham. (P. 143.) 



EX CATHEDRA. 

Prepaid Line We must ask senders of line advertise- 
Advertise- ments for insertion in the " British 

mentn. Journal " to note particularly the follow- 

ing items. Some of them are fresh war-time provisions, 
necewitated by the depletion of our publishers' staff. 
Others are •{ long standing, but are so often neglected by 
advertisers that we would impress upon these latter the 
great amount of clerical wort which is caused by their 
insufficient attention to the charges and conditions on 
whtcli prepaid line advertisements are inserted. 

Advertiaements must now be fully and correctly prepaid, 
oUierwiie they cannot be inserted. 

The charge is la. for 18 word* or leas ; 2d. for every addi- 
tiboal 3 words or leas. 

In tha case of announcements under a box number, the box 
nnmber and oor uobliahers' addreas muat be reckoned aa six 
words, and a remittance of 4d. (in addition to the charge for 
the bare anooimceineot) made to cover them. 

In no circooMtanoea can advertisementa be repeated from 
praTions iasues unless the announcement, as previously printed, 
ia sent witii the order and the full remittance. 

Advattiaen are urged to post their announcements whenever 
poaaibia on Monday for publication on Friday. Postal de- 
liveriea being now very often irregular, the ordinary normal 
day (Wedncediy) for the receipt of line advertisements novr 
generally throws such an amount of work upon bobh our pub- 
lishers' staff and oor printers that the earliest possible posting 
is a naoeaaity for appearance on the following Friday. 

Small pra|>aid adveciiaamenta will be accepted up to noon 
on Wedneadayi. instead of 2 p.m., m hitherto, but their in- 
seftion ia conditional upon space being available. UsuaJly 
at this davaoth boor it is diflicult to allocate space. 

Any notice of cancellation of a line advortiaement or of 
altaratioa in it most come to hand at the latest on Tuesday. 

No adTertisemenia can be accepted on the telephone. 

If the senders of prepaid advertisements will give the above 
the briefeat consideration, they - ips realise that 

they are necessitated by the circui of the time. A 

AqMlK staff cannot now, as hitherto, undertake to make 
a teparate and snbaequent application to advertisers for the 
balance of money which they have failed to remit. As 
regards repeat aidvertisements, senders must understand 
that their omission to supply the announcement previously 
printed entails a search among hundreds of advertisements 
with an expenditure of labour which is not now possible. 
The receipt of advertisements on Wednesday instead of on 
Toeaday morning makes all the difference in dealing with 
them at this office, and in getting them accurately set up in 
type by the printers. We do not now accept any reroon- 
sibility for printers' errors in advertisements, but adver- 
tisers have tiiis matter largely in their own hands, and can 
contribute to accurate publication of their announcements 



134 



THE BRITISH JOURNAL OF PHOTOGRAPHY. 



[Maruli 22, 1918. 



by posting them on Monday. The alteration from 2 p.m. 
to noon on Wednesdays (for a limited number of advertise- 
ment«) has been made in view of the fact that the offices of 
the "Journal " are now closed from 1 to 2 p.m., and that 
therefore the later hour, jireviously in force, actually 
became 2.30 or 3 o'clock. 

* » * 

Cold Hypo- The use of the bath of alum and hypo- 

Alum, sulphite at a temperature round about 

100° has become standard practice iu this system of toning 
to such a degree that it is not uncommon to meet photo- 
graphers vho are unaware tliat the process can be worked 
in the cold. In ordinary circumstances there is not much 
to be said for this variation, although it would seem to 
he practised to a fair extent in the United States. Here 
its slowness has condemned it in the eyes -of commercial 
photo-printers, and surely our American friends are not 
less exacting in this respect. Without seeking to find a 
.solution for this discrepancy of o])inion, it may be pointed 
out wth greater prominence than th-e brief reference in a 
recent "Assistant's Note " that the cold process at times 
may save the sitiiation when dealing with paper which 
repels all the ordinary anti-b'ister prescrijitions. Instances 
occasionally come before us where fixing-hardening baths 
and the like prove ineffective in preventing blistering in the 
hob hypo-alum. In such cases, particularly if the work 
is strip-printed and aipple dish accommodation is avail- 
able, the cold bath will often make an end of the trouble. 



More About The way students are too often misled 
Lead Glass. jjy " authorities " is aptly illustrated by 

a quite mp-to-date iuStance. Recently in an " Ex 
Cathedra " note on chemical glass we referred to a paper 
read at the Society of Glass Technology, wherein, as the 
result of ex7)eriments, the authors claimed that lead glass 
showed greater resistance to boiling acids than any modern 
chemical glass. Almost simultaneously a text-book on 
glass aj]>pears in which it is stated positively that heavy 
lead glass is attacked readily by mineral acids. We have 
no doubt as to which statement seems most likely to be 
incorrect, and that is the second one, but in a case like 
this how is the student, without experience, going to get 
an idea with regard to the facts? Books, especially those 
of the text-book variety, carry much weight in the mind 
of a student, who takes some time to realise that people 
who write books are not necessarily always correct. A 
piece of careful research, ibaoked by experiments, will out- 
weigh any book statement in the mind of the more ex- 
perienced, but the student is confused, and his progress 
is much delayed, by contradictory statements on matters 
of which he has little personal knowledge. 



Research in We hear so much about research, and 
General. .scientific research especially, in these 

<lays that it is to be feared that many will be deterred from 
supporting research generally from a mistaken idea of 
what it really means. In the popular mind scientific 
research is associated with the laborious efforts of some 
dry-as-du.st philosopher to produce sug^r from coal, or to 
effect some similar magical change of problematical value. 
This idea is not encouraging, and as science and scientific 
are words so much misunderstood by people in general, it 
might be better to use them rather less freely. In point of 
fact research is merely self-study, which takes us a little 
outside the limited domain that can alone be covered by 
ibooks and teachers, and so enables us to make real pro- 
gress. Fuirther, this self-study helps to expose ancient 
stereotyped errors of which there are many in all branches 



of knowledge. There is indeed no sulbject in the -world 
in which research is not possible and desirable, or in which 
it is not essential to the individual who desires to succeed. 
Years ago one of our most valued and respected instructors 
had one invariable answer to every pupil who asked for 
information, which answer was, "Find out for yourself," 
and until that pupil had fairly exhausted himself in 
the endeavour to find out, not a scrap of help would he 
get. That is the whole essence of research, finding out for 
oneself, and the practical, as well as the moral, value of 
such training and experience must be evident. The 
methods of the researcher must be scientific, inaismuch a> 
they must be orderly and adopted with definite intent, but 
the subject of his research may be quite unconnected with 
any (branch of what is called " science " at all. He may 
be a bu,siness man pure and simple, a book-keeper, a shoj)- 
keeper, or an artist. Whatever his oc-cupation may be 
research is possible, and, more than that, it is essential to 
his success. 



PERSULPHATE REDUCTION, CHROMIUM 

INTENSIFICATION AND URANIUM TONING. 

The twentieth Traill-Taylor lecture delivered last year by 
Mr. C. H. Bothamley, but only quite recently published", 
takes the form of a review, of what the author calls 
■' Minor Prolcesses of Photography." These processes • 
are: — Reduction with persulphate, intensification' witli 
chromium, and toning or intensification with uranium. 
The last of these is almost an obsolete process, but, still, 
it is one of which it is well to be reminded, for, if 
further investigation can take away some of its inherent 
defects, it is a process well worth reviving. There is pro- 
bably no other bromide toning process capable of giving 
such fine effects. The other two processes are, however, 
of very considerable immediate practical importance, and 
are not likely to be superseded ; therefore, we feel it very 
advisable to correct one or two statements of Mr. Botham- 
ley's which are likely to give a false impression, even 
though criticism of a Traill-Taylor lecture may appear 
to savour of sacrilege. 

The first subject treated is reduction with persulphate, 
and the use of potassium persulphate is deprecated on the 
curious grounds that a stronger solution than 2 in 100 
cannot be made at ordinary temperatures. Why this 
should be a valid objection we are quite unable to under- 
stand, seeing that a 2 per cent, solution is far too strons: 
for use. One per cent is as vigorous as any one can 
possibly desire, a weaker solution still is advisable. 
Ordinarily we use a saturated solution diluted with an 
equal quantity of water, and within the past few davs 
such a solution has been giving perfect satisfaction at a 
temperature of only 50 degrees F., at which it is quite 
impossible to make a 2 per cent, solution at all. This 
solution was probably of not more than f jjer cent, 
strength, perhaps less, but was of full vigour. W^e in- 
variably find a half-saturated solution, with one drop 
of strong sulphuric acid to every 4 ounces, a most .satis- 
factory and reliable reducer, and, certainly, both more 
convenient and dependable than one of the ammonium 
salt. 

A somewhat debatable point fS Mr. Bothamley 's con- 
tention that the milkiness seen in the persulphate solution 
is necessarily due to chloride. It may be due partly to 
chloride, and, in fact, there is no doubt that silver 
chloride is frequently formed, but the chloride is prac- 
tically insoluble in persulphate, whereas a great deal of 
the milkiness frequently observed is soluble, appearing 
only when th,e solution is in use, and disappearing when 
the plate is removed from it. Mr. Dodgson has shown 



\Urek 22. 1918.J 



THE BRITISH JODBNAL OF PHOTOGRAPHY. 



135 



that in the course of reductiou, silver sulphate, silver 
persulphate, silver peroxide, and silver oxide are formed 
in succeBsion, and the appearance of, and disappearance 
of, the milkiness may indicate the course of some of these 
changes. The older idea that it is chiefly sulphate in 
excess strikes as as more likely than the suggestion that 
it i.s always chloride. The conditions under which milki- 
nesB appears are somewhat indefinite, but it seems that 
it ia favoured by using a solution that has already done a 
groat deal of work, and is therefore loaded with silver. 

A review of the process of reduction with persulphate 

■hould certainly contain some reference to Mr. Dodgsou's 

important investigations, which were published in "The 

'hotographic Journal " for July and September, 1911, 

•lile the use of a sulphite fixinp-bath after the operation 
' reduction also seems worth mention. 

The second subject dealt with i? chromium intensifica- 

• n, and here Mr. Bothamley dofs not seem to be fully 
.„,;„f.vj ^it,h the work of Carnegie and Piper. This 

from the fact that ho L-ivee references to only 

• > ouL 1)1 the five instalments o! tlieir 1905 paper, and 
:ss«e several important niatf^r- 'icalt with in tne other 

three* He sn\ ' • -tp'i trnt the chromium com- 

pound might b- ni.it'- As a matter of fact, 

-ated in the I'JU.'i article that thej had abandoned 
.«a of it* Heine; chromic rhrorrtste, «« an extensive 
:ie» of r. ve test-" shov i much 

'wjer reset: 'o the coinpn is pro- 

ibly a complex of chromic and chromoas oompounds. 



In the same article these two investigators also con- 
sidered the nature of the silver chloride compound formed, 
and that of the active constituent of the bleaching solu- 
tion, which latter they considered to be {>otassium chloro- 
chromate. Seeing that a simple solution of this compound 
is now very commonly used as the bleacher, it seems 
probable that this conjecture was correct. 

Mr. Bothamley seems to misunderstand Mr. Cunning- 
ham's paper, to what he refers. Mr. Cunningham, so 
far as we can see, referred only to the increa.se in size of 
grain produced by the addition of chromium (which ha 
illustrated admirably), and not at all to the increase due 
merely to the redevelopment of silver chloride grains. This 
latter factor of intensification was considered by Carnegie 
and Piper, but not mentioned by Mr. Cunningham in llis 
paper. 

In the section on uranium toning, Mr. Bothamley has 
done useful work in reviving some old methods and expe- 
dienta in danger of being forgotten, but he has omitt«d all 
reference to sulphocyanide, either as an ingredient in the 
toning solution or as an after "fixing" bath. This was, 
however, a most valuable auxiliary and much used, while 
time has shown that its effects were very beneficial. The 
hvpo bath that he mentions as a fixer was a practical 
failure, as, while it umlouhtedly remove<l the soluble silver 
salta, it ruined the tone of the image. The hypo bath gave 
a crude red colour that was intolerable, while the sulpho- 
cyanide gave a very pleasine tone, and was just as efTective 
in other respects. 



SOME MINOR PROCESSES OF PHOTOGRAPHY. 



(The Twentieth Traiil-Taylor .\I>.Miiorj«J Lecture d«;liv>>rc(I Ufcre i)u- iloval rbotograpliic Society by C. H Holhaiuley 

.M.Sc. I. I.e., 



(Conimiud from pu/* 134.) 
Inlenalfring and Toninf with Farricyanides. 



Iho uraniam »nd fprrii-^ 
•!• and totung printi tri- 



1. rtu5 iiintjn- 
'\j dopositwl . 



Silii 






]citm v.rnp! ■■ 



or the dhadows o! 



■Ji. i&Od.j 



1906 r*(cren:M> are: "The Am«tear Photographer' 
13. aO. 27. and .I.ilv 4. 1905. 



tmed ont i« th«> 

...It ,.n the whites 

.I'l of on Uw 

•■■ the p«T- 

.. of the 



Mr 



.-n flirlfa a colour wli>h ia well auitnl to oit- 

. .. „. . i.|y ,,'„t.iined in any other way. 

^ id capable of numcruus modi- 

•ur- 

in- 

i.eu auf 

^ Jalir 



Sixteen yean a^^o, however, L. Bane pointed a way out of tke 
' ' ' i 'le I'Aawc. Beige," 1901, 627-629). Ho re- 

:ii9 «ut the prooeM in two mooenive opera- 
i...ii^ iii>i.-.i.l uf with mixed aolutions. The well-waahed 
l>riiit i> iniinxraed in a w>lution of potassium ferricryanide (2 to 
5 in 100) until bl«ache<l, and ia then well washed. The 
hlnaclxxl imago is not aiiectod by uranium nitrate solution, 
(nit if iminersevi in uranium chloride aolntion (1 in 100), or in 
s aiilution <.Tnit.ainin(; uranium nitrat« 1, oommon salt 30, 
wat<T 100, the itn3g<- gradually rbanges to warm sepda, the 
wh:U.« niiiaininj; uii»tained. The modified {irooesa was de- 
I* rifjetl a« itpplicaWe to the toning of positive images, and it 
wat not iiugg<wt<ii that tlic same tii' 'ild be followed 

when int<-n!>ifyiir^ iv«aiive«. It ia r^ ■ , however, thai 

thi» valuable !tii;;^e»ti<>n W'>uld seem to have been entirely 
neglected, althougli I called attention to it at the meetuig of the 
Photographic Cwnvention in 1906. 

In 1906 L. J. Bunel' ("Bull. Soc. Franc." [2] XIX., 303) 
advocattsl the use of dtric acid (2.5 in 100) or oxalic acid (1.5 
'V 'upe of acetic acid, on the ground that thi-j- pre- 

'laenrhere than on the image. Ho attributed the 
Kcru-rni nUiiiiing to the formation of an unstaiblu uranium 
Wricviiiiiile. and stated that 11 a considerable quantity ef 
•alt ia dissolved with the uranium nitrate, or if uraniiun clilo- 
rido is iwed instead of the nitrate, Uie formation of the un- 
stable ferricyanide is prevented and staining is avoided. The 
p«per also refera to the method of toning positives in two 
stages. (See above.) 

Before d(«Ung with the prooeea itself, it is sdivisalble t* 



(4) Aeompariwii odbUpsper »itb tbsljaii ntemi to lonatU thkl there li 
aonw miitu* io (be nemei, Md L. Bun* •nil U J. Bunal msy be one and tke 
•sBapanos. 



136 



THl-; BRITISH JOURNAL OF PHOTOGRAPHV. 



[MaixJi 22, 1918. 



dear up one or two points conapniing the chemical i-eaotions 
involved. It is well known tliat wlien a solution of a silver 
salt is slowly added to a mixture of salts, witJi tihe acid radi- 
cl«i of which it forms insoluble salts (precipitates), the silver 
may combine preferentially with one of the radicJes ibefore 
combining with the others. If the liquid contains iodides, 
bromides, and chlorides, for example, tlie precipitate at first 
c<irisist« of silver iodide alone, later of silver ibromide, and 
lastly of silver chloride. Similarly, if silver diloride is treated 
with an alkali bromide, it is convei-ted into silver bi-omide, 
and if sUver bromide is treated with an alkali iodide, it is 
converted into silver iodide. It lias lately been stated that 
silver chloride is converted into silver ferrocyanide when treated 
with potassium ferrocyanide solution, whereas silver bromide 
and silver iodide remain unalteretl when treated in the same 
way, and these facts have been utilised in a metliod for de- 
tecting chlorides in a mixture of chlorides, bromides, .and 
ifxlides. 

I have verified tliese statements, using careffully purified 
IHjtassium ferrocyanide. 

The position of tlie fearicyanides in this series has to be 
considered. By adding a solution of a silver salt to solu- 
tions containing (a) ferrocyanide and ferricyanide, (b) fen-i- 
cyanide and chloride, and by treating (c) silver fenucyanide 
witli a solution of a ferrocyanide, (d) silver ferrocyanide with 
a solution of a chloride, (e) silver cliloride with a solution of 
a ferricyanide, and (/) silver iferrooyanide with a solution of 
a ferricyarade, it is easy to show that — 

(1) Silver forms the ferrocyanide in preference to the fevri- 
cjanide. 

(2) Silver forms tlie diloride in preference to the ferricyanide^ 
('ombining now the known results, we get the following oi'der 

of preferential formation of silver compounds : -^ 

Sulphide, iodide, bromide, ferrocyanide, chloride, ferri- 
cjanide. 

That is to say, silver will form silver sulphide in preference 
to any of the oUieirs ; iodide in jireferenoe to any of those fol- 
lowing it ; and so it will form any of the other compounds in 
preference to forming ferricyanide. The ipractioal application 
of these facts will beccnne clearer l^teir on. 

Retiurning now to the uranium process, it seemed wortli while 
to ascertain how far the precipitation of uranium ferrocyanide 
which causes the staining (a) depends on the uranium ssalt 
used ; (b) is affected by light. 

Using very pure samples of uranium salts and of ijwtassium 
ffci riqj-ianide, I found that if the solutions are mixed in tlie 
dark and kept in the dai-k, there is still some precipitation of 
uranium ferrocyj.nide, which is not prevented (by addition of 
acetic acid. Exposure to diffused daylight distinctly increases 
the amount of precipitate formed. There is no distinct dif- 
ference in ibehaviour between uranium nitrate, cMoride, and 
acetarte. 

Potassium ferricyanide quite fi-ee from ferrooyauide and 
chloride readily (bleaches a negative image which lias (been 
washed free of soluble chlorides. With a solution of 5 parts 
in 100 tlie action is fairly rapid. The bleached image consists 
of siJivfcr ferroqyaaude, witli possibly some silver-potassium 
f ei rocyanide. I could dbtain no evidence that the image con- 
tains any ferricyanide, as Bunel suggested. 

lif, now, the .bleached and well-washed negative is immersed 
in a solution of uranium nitrate or acetate free fcojii 
chloride, there is no change, but if immei'sed in a 
solution of uranium chloride, or a solution of the nitrate 
or acetate to which a fairly large proiwrtion of sodium chlo- 
ride has been added, the white image giadually dianges to 
brown, as Bunel stated, and there is no staining of the shadows 
of the negatives or the whites of the iprint, as the case may be. 
Tlic action of the uranium solution is soiftewhat slaw. 

1 find that the action is much more rajiid and the colour of 



tho image is Ibright'fr and redder if the solution of uranium 
nitrate is mixed with potassium bromide, instead of with a 
chloride, but great care must be used to avoid adding any 
excess of (bromide, 'because whilst a moderate excess of chl<- 
ride does no harm, since it does not de<»mpose the silver ferr<'- 
cyanide which forms tlie image (s«' above), an exw-ss < f 
bromide may spoil llie result, since tlie bromide will then 
change some of tlie silver fei'rocyanide into silver bromide 
before the uranium salt has time to act on it. If both coni- 
|x>unds aro quite pure and dry, 100 parts of uranium nitraie 
ix-quire 47.4 ipai-ts of ijwtassium bromide, but it is advisable to 
use a lower proportion. Useful solutions ai-e: — 

A. Potassium ferricyanide 5 parts or 350 grains. 

Water ■■• 100 parts or 16 oz. 

B. Uranium nitrate * 5 parts or 350 grains. 

Potassium Ibromide ■ 2 parts or 140 grains. 

Water 100 parts or 16 oz. 

If the purity of the uranium nitrate is doubtful it is wiser to 
use only Ig parts (or 100 grains) of potassium bromide. 

Tlie tlioroughly fixed and washed negative, print, or lan- 
tern slide, is immersed in A until bleached. It is then 
tlioixjughly washed — ^a matter of great iniiportance — and im- 
mersed in B until no further change takes place. The inten- 
sified or toned image is washed in seiveral changes of water, 
sUdhtly acidified with acetic acid if the water is hard, and 
finally in three or four changes of water as soft as is proour- 
ctble. ■^ 

[The spedmens exhibited not only showed absence of stain - 
ii\g of tlie film or paper, tot also illustrated the great intfu- 
sifixjation of negatives obtainaible iby tliis method.] 

If the intensifying or toning is unsatisfactory, treatment 
with p.n alkaline developer will restoa-e the silver image, and 
the process <;an be repeated from the beginning 

The ferricyanide and uranium solutions can be used more 
than once, (but the ferricyanide solution must !be kept in the 
dark as much as possible. It is, of course, desirable t<. use 
ferricyanide .is pure as possible, but an additional advantage 
of the method of successive treatments is that if the negative 
or print is well washed between bleaching and treatment with 
the uranium, solution, a small quantity of ferrocyanide in the 
ferricyanide does no harm, whereas in the mixed solution 
method it would increase the general staining. 

It should be ob.serve<l that the comix>sition of the final image 
is not the same in the two methods of working. Xamias 
pointed out (loc. cit.) that when the silver image is treate<l 
with the mixed solution of potassium f