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A 588429
►
RETROSPECT
PHILOSOPHICAL, MECHANICAL,
CHEMICAL, AND AGRICULTURE
DISCOVERIES ;
BEIVO AV
I
PERIODICAL AND OTHER PUBLICATIONS,
£NGLISH AND FOREIQNi
« • .
XELATXVB TO
Arts, Chemistry y Manufactures^ Agriculture, and
Natural Philosophy ;
ACCOMPANIED, OCCASIONALLY, WITH
SlEJif ARXS ON THE MERITS OR DEFECTS OF THE RESPECTIVf
PAPERS;
?*v
AKDy IN SOME CASES, SHEWING TO WHAT OTHER lieEJfUif
TUKPOSES INTENTIONS MAT BE DIRECTED, J^»
DISCOVERIES EXTENDED, BEYOND THE
ORIGINAL VIEWS OF THEIR
AUTHORS.
^
VOL. VL
■'II U LX
LONDON:
PRINTED FOR THE PROPRIETORS,
AH© «OLD BY W. H. WYATT, AT THE REPERTORY Of ARTS AK^I
PATENT-OFFICE, NO. 9, PICKETT-STREKT, T*MPiB-BA»,
ST-
I 11 H| <i
0mm
PoplcMMlMUler* Prin^rp, Qld Bonr«U-Court, handtm.
T' ^
' i
COM-ENTS
01 TBm
SIX.TH VOtUMB.
KATURAL PHILOSOPHY, ARTS, and MANUFACTURES.
Pagf
Iftethod of dWiding astronomica! and other inftrutnents, by ociilac i»>
apectioU) in which the usual toob for graduating are not employed ;
the whole operation being ^ so contrived, that no error can occur
bat what is chargeable toviuon, when assisted by tiie best optica)
means of viewing and measuring minute quantities. By l^lr. Edward
Troughtoa ------ f
On an improvement in the maimer of dividing astronomical instr^-
,ment& By Henry Cavendish, Esq. F. R. S. - - H
0n a metliod of examining the divisions of astronomical instruments.
By the Rev. William Lax, A. M. F. R. S. - • IS
Description of a new cupping instrument. By Robert Healy,
MB. '• - - - - -Id
On the parabolic lens of Eospim. By Mr. CoutcB. - - ir
Beport of anew nangable canal, proposed to be cut from Okeham to
Stamford, and from thence to the town of Boston. By Thomas
Telford, esq. -*---!&
On aerial ua^0ition. By ^CreorgeCavley, bart - - J|t
Bf aching for b^ing roota for cattle, ardcles for dyei's use, or for culi?
nar^ purposes. - By Mr. Thomas Newton. - - 2f
Machine for making slate pencils. By Mr. J« llrockbank. ' - fff
Sfacliine forq^anufocturing sUk covered wire, and thread covered with
silk^ By Mr. lliomas Saddingtbn. . . . ||f
Biethods of nusing the bodies of persons who have sunk under water,
or of assisting persons in danger in vrater. By John Miller,
esq. ...... iljlL
Method of securing the beams of shi^, without wooden Knees mad«
' of one piece. By Mr.' George Williams. - -5%
Vaval improvement. By €aptain William Bolt^. * - 3S
Method of constructing commodious houses with earthen walls. By
Mr. Robert Salmon. - . . . - d^
On Iris seen in the dew, and a lunar Iris, with an annotation. By
A-M. - - - - - . 4a
^On the propagation of sound through unelastic iluidsb By Francis
Ellis, esq. with an observation by Mr. Nicholson. - • 41
Anthropo telegraph, or oiode of communication in tlie day or night
by disks. ' By Mr. Knight Spencer. - . -4$
Ifomqgraph, or method of cofluattoication by ugnals^ vn sea or land.
By MnJamesSpratt. •>.-•- Ibid,
386938
!▼ CONTENTS.
ImproYed file for receipts and letters. By Richard White, esq. - 44
Demonstratiou of the Cotesian Theorem. By Mr. P, Barlow. - 45
Proposal for an mstitution for obtaining an eqaal temperature in hou?ci.
By Dr. Pearson. - - _ _ - 4f
On Dr. Pearson's proposal for obtaining an equal temperature in
houses. By Ceneps. - - - - _ ibid.
On the means of counteracting the effects |)roduced by the Forma-
tion of gasses found in coal mines. - - - 4S^
On the method of transforiBing a number from one scale of notation
to another, and its application to the ride o( duodecimals. By Mr.
Peter Barlow. - - - - ' - _ 51
Inqiuries concerning the influence of light on the propagation of sound.
By Modeste Parolette. - - - - 57
On th« camera lucida. By Mr. f. Sheldrake. With a remark by
W.N. ... . . . -. 6«
Qn the camera Incida. By Mr. B. Bate. ... ibid.
Ob the use of the camera luada as a substitute for the camera obscura.
By Mr.T.Sheldrakf. - • . - - - ibid,
Observations on loaded and unloaded barges, boats, beams, or floating
bodies descending with streams or currents, and why the heavier
end will go foremost. By George Orr, esq. • - . - 6t
On the Volcanoes of JoruUo. By Alexander Humboldt. - - 117
Report made to the French Institute, on a Memoir of M. Delaroche
f>n the Air-bladder of Fishes. By ]\|[essrs. Lapecede, Yauquelin,
andCuvier. - - - - * . IJq
Ta^le of Kain, that fell at Various places in the year 1809, by the
"Rtr. J. Blanchard, of Nottingham : with a Meteorological Table
for the same Year. By Dr. Clarka ofthat Town. - - %f5
IJn Azimuthal Refraction. By Mr. Charlas William*. -. ' - ttj
Kcmarks upon Meteorology : with a Specimen of a New Meteoro-
logical Table. By J. Bostock, M. D. Remarks on Meteorology.
. By Thomas Foster, Esq. - - - . - iSi
Qn the Art of Printiiig with Stone, and especially on the Progress
which this Art has 'made in Germany. By M. Marcel de Scrres. 1381
On. the power of the Eye, by which it is adjusted to ttie Objects
distinctly, at diflierent Distances. By Ez. Walker, Esq. . 140
jKote of a Discorery of Mr. Varca in Magnetism. - - 14!^
Sxtract from a Memoir of Messrs. Mouchci, of I'Aigle, in the De-
' partment de TOrne, on the manufacturfc of Iron and Steel Wire. ibid.
On the construction of Theatres, so as to render them se-cure against
,Fire. By Mr. B.Cook. - - - - 145
Tools to answer the purpose of Files and otlicr Instruments, for
rarious uses of Stone-ware. By G. Culiiberland, Esq. - - j4f
An Inquiry, Geometrical and. Asfthmetic^d, into certain Properties
of Solids in general, and of the five regular Bodies in particular.
By John Gough, Esq. - - - - 1.^0
Description of a Clock Escapement, invented by Mr. George Prior,
Jun, ' ' - - - J 131
Jpescription of the Frepch Telegraphs used ort the Coast of Flanders, &c.
with . Observations on tiie sanrp, and a plan of a Poly'.raniuiatic
Telegraph on a new construction. By Cap. C. W. PdVlcv. - 152
Account of a Method of dViving or forcing forward Si«ips'"or other
Vessels by tlie power of Steam Engines. By Mr. Jaraes Linaker. l.'iX
Op the Composition and Decomposition •( Forces By ]\lr. W.
If arrat. ' - - - - r 155^
COKTBNTS.
Dtscription of an !Eye Bath, to clear the Eye from extraneous matteri»
and to assist the Siglit. By Mr. John JJuckelt Ross,
Kew Theory of the Diurnal Motion of the Earth round its Axis, By
Professor Wood, Richmond Academy, State of Virginia. ^
^n Telegraphic Communications. ' By Richard Loveli Edgeworth,
• Eaq. . - - - - - -
Obserrations -on Dr. Bostock's Remarks upon Meteorology. By Luke
Howard, Esq. - - - • - ..
On Meteorological Nomenclature, in answer to Luke Hovrard, Esq.
By J. Bostock, M. D. - -
Remarks on Mr. Richard Walker's proposed Alteration in the Scales
of Thermometers. By Londinensis. - - - ,
ll^ote, relative to a Method of constructing wooden Bridges. By M,
Wiebekrng. - - - - . •
On Pendulums. By Ez. Walker, Esq. - - -
^experiments on the comparatiye Powers of the Cylinder and Plate
Electrical Machines, and on a means of doublings trebling, quadru-
pling their charging power. By Mr. John Cuthbertson, and Mr,
C. J. Singer. -----»,
On the Discoveries which Daerfel and Hevelius made in the Theory of
Comets. By J. C. Buckhardt. - ' -
On the Action of the Electric Fluid, by which an Iron Cylinder an ^
inch and a half tliick was torn asunder -, in a Letter from Mr.**** to
J. C. Delametherie. - - .
Kemarks on the preceding Experiment. By J. C. Delanetherie.
On the Ring of Saturn. By M. Laplace. ...
Memoir of the Determinatibn of the Obliqalty of the Ecliptic, which
results from ancient observations. By M. Laplace.
Proposal tor constructing and putting in its place, an Iron Tunnel un-
cter the River Thames. By Colonel Lemion. - * -
pescription of a Metallic Thermometer for indicating the higher De-
grees of Temperature. By Richard Walker.
On the Influence of So)ar and Lunar Attraction oa Clouds and Ta*
pours. By Salem Harris, Esq. - . -
On prime and ultimate Ratios, with their application to the first Prin-
ciples oft he fluxionary Calculus. By Mr. W. Marrat.
On the land winds of Coromandel, and their causes. By W.Roxburgh,
M. D. - - - . - -
I^marks on a new principle introduced by Legendre in his elements of
geometry, by Mr.T. Knight. •- - - -
iVccount of a new method of increasing the charging capacity of elec-
trical jars, discovered by J. Wingfield, esq. By J. Cuthbertson.
Pemonstration ot acurious numerical proposition. By Mr. P. Barlow.
S^ond vindication of Br. Herschel's theory of coloured rings, in an-
swer to an anonymous reviewer. - - - -
J^ physical view of the equatorial regions, from the tenth degree of
north to the tenth degree of south latitude, drawn up from measures
and observations made on the spot, between the years 1798 and
1804. By Mr. Von Humboldt. - - - -
Historical note on the means employed by astronomers for observing
the sun. By J. C. Burckhardt. - - - -
Table of the tides for the year 1811. By Mr, Bouvard. -
.On ttie application of the barometer for indicating the weather, and for
measuring of heights in the atmosphere.
On the barometer. By Richard Walker, esq. -
^n the baroiaeter. By R. Walker, esq. t ^ ?
Page
159
509
314
SIS
ibid«
SU
ibid.
Sir
SfS
ibid.
srr
SSt
sss
541
37S
576
37«
ibid.
580
Stl
387
589
390
594
iUil.
in CONTBNT».
P«g«
ObseiTHtions on tvhdel carmges, roads» and draught of lun-ses, inTesti-
gstions of' the mechanical mode% of action of , the horse, and of the
size and breadth of wheels, and descriptions of three new species of
wheels, contrived to facilitate draught, and to preserve the roads;
with some remarles on asUes and boxes, and an account of a proposed
improvement in harness. Bj J. W. Boswell. - - S9H
Description of a camp telegraph, invented by K. Spencer, esq. - 405
l|ec(nt state of the iron manufactory in Great Britain. - - 405
Engraved slates for teaching writing and arithmetic, by Mr. T. Wairen. . 40^
Scheme for preserving the lives of persons shipwrecked. - - 409
Supplement to the first and second part of the paper of experiments^
ier iirvestigating the cause of coloured concentric rings between ob>
ject glasses, and other appearances of a amilar nature. By William
Herschell, LL.D. F.R.S^ - - - - 468
tAiocrvatioQs on atmospherical refractioi) as it affects astronomical ob-
servations; in a Lettet from S. Groombridge, esq. to tlie Rev. Nevii
Maskelyne» P.D, F. R.S. Astronomer Royal. (^ • 47'tf
ISstract of a letter from the Rcr. John Brinkiey, B. D. F. R. & An?
drews professor of astronomy in the University of Dublin, to the
Bev. NeviJ Maskdyne, D. D, F. R. Si Astronomer Royal, on the
aanual paraHax of a lynoe. - , - - - ilMd,
A short account of the improvements gfadually made in determiniag
theastronoNuealiefracI^. - - - - it»id,
Bpme particulars respecting the thunder storm at l^ndon, and in its
Ti<inity, on the SUst o£ August, 1810. By Sir H, C. Eoglefidd,
hart. F. R.S. and F. S. A. - • - - - . 483
i>n the mountain barometer. . By Sir H. C, J^glefield, hart - 486
y^sAs respecting a new theory on orbits of comets. By Mr. W. Crane. 486
i>n the penetradoa ofbaUs vf^to uniformly resisting substaaccs. Bj
W*Mpo{«, esq^ - ' ^ • - 487
REVIEW or SPJICTFICATIONS op PATENTS,
JUTr. John Leigh Bradbury's for a method of spinning cotton, flax and
wool. - - • - ' - €6
|ffr. Fredenc Bartholottiew Folsch*s for several improvaments on cer-
tain machines, instrumepts, and pens, calculated to promote faci-
Efy in writing. - - * • - -67
If r. Edward Manfey^s for a plough. - , - - * 68
Mr. William Hutton's for a method for making tickles and reaping
hooks. * - - - . - - -69
Mr. John Bartoo*^ for a lamp of a new construction. « . / - 70
Xfr. John t)\xS*a fot snu^rs of a new and improved construe*
tion, - r - - - - 71
JfiTr. James Rarron^s for improvements in the apparatus used for rollers
for window blinds, maps, and other similar objects. * - 7t
Mr. George Pocock's for his inveni ion of geographical slates for the con-
struction of maps. - - f. ** -
Jlllr. John Jones's fpir in^provementsin manufacturing ofskelps for fire
arms. . - . . . . ibij^
Mr. David Meade Randolph's for certain improvements in the con-
struction of wheel carriages of every description. - - 7^
Iff. John Dymbcirs for a method or methods of flax spinning, and of
preparing or making a species of twist, thread, furniture, cloth, trills,
or attire, wliich he calls Teiary Tegument^ from si|k, wool, cotton.
P^
flm, Ken)p» or tow, ts well is from a yery gr«at vtn^ety of otlier nrw
tides, in a combined or uncombined state ; and for a method or me-
thods^of refabricating or renovating the same, and of produdng or
reproducing, from tatters in general, anew body. * • 79
;^Ir. John Manton's for an improved lock for guns and pistols. « QO
idi. John Wliite's patent for the dbcovery of a s«tbstance> capable
of being converted into statues, artificial stone, &c. - - '1^
Mr. Mare Isambard Brund's patent for cutting veneers or thin boards
by machinery. ..... IIh4«
Mr. Augustus Frederick de Heine's patent for improvements on print-
ing and stamping presses. .... -j^i^
Mr. John Manton*s patent fon improving timekeepers - • lOt
Mr, Phiilis Brown Thompson's patent for umbrellas and parasols. - '163
ISdr. John Schmidt's patant for a phantasmagoric chronometer, or
nocturnal dial. .... . . ^9^
3^. Charles Le Caan's patent for an apparatus to «heck the action
, ofcfu'riages. . - - . . xfl$
Itf r. Randijph Tsehi^Q^ 6m Boehe's patent for improvements in the
process of brewing. - . . . . tOS
Mr. John Frederick Archbold's patent for a method of converting
salt or sea water into fresh water. ... . ^ff
Sir. Charles Valentine's patent for a new mode of ornamenting and
- paii^dng all kinds of japanned and vamuhed wares. - • fUd.
JlCr. Peter Warbnrtbn's patent for deooratmg ohina, proceluo, earth-
enware, «nd gloss, with gold, silver, platina, and other metals 109
Bf essrs. John Marshall, and John Kaylof s patent for manufacturing
.and making salt. . .' . . . • ifo
'Vt, John Penwama's patent for a process Ibr giving to statues or other
omamtntai works in plaster, an appearance nearly resembling the
finest statuary marble. ... . . 34$'
Mr. John Thomas Srove's patent for an improved mode of construct-
ing buildiiws, by which great expcnce, labour, and time aiesavedt
and thebswlings secured iitom the dry rot, with other advaata^ - M4
iMr. Jamas Goddard's patent for manniacturing a certain description of
iroodenboxes,oalled chip or mil boxes. . - . ^45
Mr. William Dockse^s patent for conMderable improvtments in the
process of manufiirtming ivory black ; and for pulverising .all arti- -
cides capable of a more easy separatioQ of their parts or coDstituient
principles. -.---- S4f^
.Mr. John Cruge's pattnt for an improvedkitchen fire-place. • A^B
Jttr. Richard Witty's patent for making, arran^ng, and comfainingoer-
tain parts of rotative steam engines, by which means the most com-
plex parts of the steam engines now in use are dispensed with. - M'
.Mr. Jamas Hall's patent for making shivers and puUej whoeb of
earths and minerals. ...... J51
Mr. John WilUam^s paiOBt for a certain appnratus to be applied to
And used with whtel carriages, in order to render the same more
safe and -comouKlions. ... - . - ^jjg
jMr. William Congreve's patent for a mode of constructioa or arran|(e-
ment for any boiklnig so as to afford seouHty against fise, with
other advantages. - ^ - - - — *> S5S
^r. John Shtet's patent for an impsovement in hanging and -securing
•grindstones frombreakinginthe middle or the centre. - - S5^
IjHr. Joseph Warrau Bavere^s patent for a new and improved.method
of splitting hides, and-^bAving- leather, conununicated-to him by li
foreigner* ... . - . 410
Viii doKTENTS*
Ifr. J. Vart^?8 patent for certain improvements in the axle-trees of car-
nages.
411
If r. C. Williams's patent for a machine for grinding or cutting malt,
splitting beans, or any other kind of grain, and various other arti'*
cles. - . - - * - - 41«
Mr. E. Shorter** patent for an improved apparatus for working of
pumps. - - - - * 415
Mr. J. A. Berolla«*« patemt fdr a warning Watch upon a new construe-
tion. - - --. - . -^ . 4/4
Mr. J. Maiben*s patent for an apparatus for making carbonated hydro-
gen gas, and applying the same in lighting buildings, &c. - 415
Messrs. Wm. Shakespear and Thomas Osier's patent for a new and ira-
proTcd methoci or methods ot manufacturing glass or paste drops for
chatidcliers, lamps, and lustres. - - - - 41T
Mr. Stephen Hoopar's patent for a thermometer, or machine for ascer-
taining the heat of bakars' ovens, and various other purposes. - 413
Mr. John Onion's patdnt for a machine for thrashing corn and other
grain, on a new construction. - ^ - - ^ - 41^
Mr. Frederick Albert Winsor's patent for improvements in his oven
ateve, orapparatusforcarbonizingallsortsof raw fuel, &c. and for
extracting the oil, tar, pjrolignous acid, and ammoniacal coal li-
quids, -and for extracting and refining all the inflammable air or gas. ibid.
Mr. Joseph Stevenson's patent ibr a machine for filtering and purify.
ing water. - - - - - - 490
Mr. Thomas Robinson's patent for a mashing machine. - - 494
Mr. William Watts's patent for methods of combining and disposing
. machinery, and applying the different powers of wind, water, and
cattle thereto, so as to effect improvements on mills. - * 49*
AGRICULTURE.
On planting forest and other trees. By A. C. R. of Castle Combe. 81
On the price of Anglo Merino wool. By Benj. Thompson, of Redbill
Lodge, Notts. - - - ' - - * tit
'On the Anglo Merino question. By Agricdla Northumbriensjs. •» ibid.
Observations on the speculative opinions of Mr. Thompson ; and expe-
rimental evidence of Mr. Wright and Mr. Hose. By John Hunt>
of Loughborough • . - - - . ibid.
On shoeing the ox and the horse. Br Clericus, of Buckinghamshire. 85
On the drill culture of carrots. By R. S.D. ofWindsor Forest. - ibid.
On the culture of carrots. By A.N. F. of Worksop. - - ibid.
On coverings for hay and corn ricks. By Economicus, of Aylesbury. 64
Hints relating to an improvement on the thrashing machine* By Alex-
ander Scot^, of Ormiston. - - - . ibid.
iOft the potatoe curl. By James Inglis, of Parkhoira, near Glasgow. - 85
An useful premtratory step when thorn hedges are to be planted on
clay soils. By John Reid, esq. of Castle Hill, near Kilbride. - ibid.
^imate of the expence of inclosing by hedge and ditch. By R. G.
of Perth, • - - - - -9^
On the expense of inclosing by hedges. By Calculator, of East Lo-
thian. - - - - - - ' - ibid.
On the inutility of plucking potatoe blossoms. By the Rev. Charles
Findlater, of Newlands^ - - • . | ibid.
Kew plan for coustiQcting roads. By Messrs. Winton and Nisbet, of
Kdifljburgh. •-*--.-H'
li)n th« compawtlve Profits of Wiltohire Merino-otosi Sheep. By
Morrif Birln^ck, of Warborough, in Surrey - " . * *^
X}i tlie culture of parsneps io the Island of Jersey, and tlieir utility
in feeding Cattle. By Charles Le Hardy, Esq. - - . JS4
On the properties of furze and w^iins. By Major Spencer Cochrane,
of Marsfieid Houses North Britain - - - - 9Sf
Circumstances relative to Merino ah^p, chiefty collected from the
Spanisli ihepherds, who attended flocks to tms country. By^r
Joseph Banks, K. B. - - . * . .' " * ^^
On Sicilian wheat. Queries from Sir John Sinclair, with dnswers, by
the Prince di Castelcicida. - - ^ ^ - - 285
Hints regarding a Spanish grain, called Bscanda. ^ Sir John Sin-
clair, baft. . - - - - - 2tPf
On the use of barley for horses. I>ra,wn up by order of the Board. - 28S
On naked barley. By Warren Hastings, esq* • - • 28^
On Grecian barley. By Coloiicl Mitfwd. - - %- t90*"
On the use of soap<mak«iv wastfc ashe3, commonly called soapei^
waiste, as a manure. Drawn up by prder of the Board of Agri*
cnltnre, and published by ifs direction^ • . «. f^x
Queries regarding experiments with long diing, with answers. By
T. W.Cokc,esq,M.P. * • - • f9a
Ob irrigation. By G. R, Eyres, cso. of Lynford Hall, Norfolk. ' • . S9S
On the mapfe tree. By James Hfallt esq. . - . . • llud.
On the advantages tti^ bo deriyed from heath in feeding of stock. By
James Hall, esq* - - - - . 29^
Horses and oxen compared. By the Rev. R. Kedington^ <^ Rougham^
nearBurV) Sutfoik. - - - • . ^95
6n oxen. By David Barclay, esq. - ' « - 504
On horses and oxen compared. By Mr. Whitworth. • • ibid.
Memoir on seed grain. By Sir Joseph Banks, K. 6. • - ibid.
Comparative experfments on the culture and application of kohl-
rabi, drum-headed cabbage, and Swedish turnips. By Mr. John
Saddingtou, of flnchley. -■ - - . f9^
Oa * preparation from bean-stalks, as a substitute for hemp. By tlie
Ker. James Hall, of Walthamstow, Es&ex» -' - . 299
.On planting oaks. By William Cougreve, esq. of Aldermarston
House, inBerkshire. - - - > - . ^90
Statementofdrilled and broad-cast husbandry. By Messrs. Betchelor,
ofXidliiigton. - - - - • 301
Account of land gained from the sea. By Mr. William Laurence. • ibid.
On the management of cattle in the Highlduds of Scotland. . 30jt
Oft the mode of preparing Frciiuh vinegar, and- the ditfcrent species of
the article wliich are raanuiactiired in France. - - 303
Description of a threslili'ijj milllutcly iuveniecL ByW. B. - 304
Thought9«0!i the-perlods of so wing i;eeds of different kinds. By A. M. ibid.
Cheap plan of a sheep-house^ B3' A. S. - - ■ - %q$
On the irapropnety of mixing the seeds of grasses, when Land is
sown down for paKturage. By T.Ir. James Ileadrick. - - ibid.
Odl the disease in cattle called the blark ^pald. ByW. F» • 30fi
Ol[>scrvations on the u;se oi lime. ByO — a — s. - \ • 30^
Observations on the method of laying down pasture and meadow
Land, with an account of some pas^ires made with the meadow
Rescue grass and clovers. By Mr. W. Salisbury, of Brompton. - ihjid.
An essay on the mathematical construction of a ploogli, wtiich slmlt
»fier the leakt resistance, and which filial! turn a furrow ^ ]
offer the leakt resistance, and which ;uiaU turn a furrow ^ the b^t
manner. - • > - «. «
b
.5^
On comliiuing two» thrr^, and four of these ploughs t6getfaer» to ai to
faveonc-tbiirth of the ordinary expence of ploughing. - - ibid.,
On the construction of a d^hanomcter for measuring the relative resis-
tauces of ploughs. - - - - ibid..
'On tlfe construction of a new fashioned roller, and of a nev set of Iiar-
rovfs foir harrowing aud rolling corn in the spqiig, and in moist laud ^
wifliout tlie horses treading it. - - - - ibid.
On breaking young iiorses and oxen to all linds of work easily, safely,
and ex|)editionsly. - - - * - - , ibid»
On ^1ie construction of wheel carriages upon a new principle. By Mr.
W* Amos. - - - - - - " ibid*
A letter to Sir John Sinclair, bart. containing a statement of the sys-
iei9 under which a considerable farm is profitably managed in Hert-
fordshire. By T. Greg, esq. - - - - 361
I^Lcmorandum as to spring crops without spring ploughing ; also as to
arable land. By Mr. D. JVIaynard.of Wliittlestonl, near Cambridge. S69
£x pe'rimcnt. between spring wheat and barley. By Mr. Adam Ruther-
ford, of poniugton Park. - - - - 56S
0*en and raolit&ses. By E. T. Waters, esq. - - • 364
On Swedish turnips. By A.Bacon, esq. - - - ibid.
E^pcfiments on weeding broad-cast crops. By Mr. J. Wright, of Pick- .
worth. - - - - - - - ibid. .
On spring wheat. By the Rer. Mr. Mounsey, ©f Sproxton, nearMeU
toii 'Mowbray. - - - • S65 ,
On d rah ling. Fy R. Ramsden BramTey, esq. - - - ibid."'
Oh courses lif crops, and on feeding. By W. N. - - ibid.
On bcxagorial or Ficnch barley, and on the Swedish or naked barley.
By IMr. C. VV. S. pHgct, of Pangbourh. - - . 66f
Oh polled cattle, by the keeper of a few cows at Cheshunt, Ilerti. * 367
On giddiness and stfurgcrs in sheep. Byll. G. - - ibid.
On th^ useof lona dung. By J. Bright ley. - - • ibid.
On the celebrated florin, or butter grass. - - - . 368
Op fiorin grass. " - ' • - - - - ' ibid.
Oh the advantages of feeding horses with steamed potatoes instead of
corn. - - ... . , ibid*^
OK^miut in wheat. "By Mr. BatchelAr, of Lidlington. - - 369
Msch;ue fof washing potatoes and oiher esculent roots for feeding cat-
Hie. By Mr. W. LtstcT, of Paddingtoii. ^ -' - • - Ibid.
On ])lanting larch trees. By .T. C. Ciirwen, esq. M. P. - - Srt '
Description of a mctliod of packing plants and trees intended for ex-
poriaiion." By Mr. W. Salisbury, of Brompton. - - S7t
On planting ash, chesnut, elm, aud other forest trees. . By W. M. \
Thackeray, M.D. of Ctiestcr.* - . - - 37-5
A detail of experiments to ascertain the daily quantity of brown Mus-
covado sugar necessary to fatten sheep; to shew its effects and ralud
when 'SO 'applied, *anrt to demonstrate what substance or substances
'snfTiciently cheap mi^ht be mixed with it, so as to prevent its
application to common uses, and yet render it not unpalatable
norpernicious to animals which feed upon it. By the ilev. Dr.
'Cartwrijiltt. ' u - . - . . 44^
Communication! (respecting what Grasses are more particularly
adapted for meadow grounds, and what for pasture, and whether
* it is betJer' always to mow, or pasture the ground, cr to mow and
pasture it in rotati(»n\ By Mr. William Slickney. - - 44f .
Communications respecting the comparative benefit or injury to the
hirmer, froaA rooks, pigeons, &c. By Mr, William islickttcy. - 4§#
CONTENT*. Xi
. . " ?«?•
Further commnnicaUons from Mr. Cramp, of Lewes, respecting the
produce of liis cow. - - « > 45^
Essay on tlie fertilizing effects of Gypsum in the United Slates of ^
ikmerica, with a view to elucidate its mysterious operation, and
to extend its benefits to England, and other parts of the Brilisb
dominions. By M. A. Fortier^Ui, JM. D. F. R. S. of Pkiladtl-
phia, - - . - - 45i
Observations oi> the jQat«ral liistory of marl. By R. G. of S. M,
near Perth, - . . , ^^
On the use of sea sliells as a manure. By Domeaticus; - 4.55
On Ruta Baga. By a Northumberland Farmer. - • 4^
Observations on the raisuig of turnip seed. By J. G. F. . ibi^.
On the cultgre of flax seed. By a Friend to flax seed. . 457
A new method of yoking horses in- thraulung machines. By Mr.
John Gladstone. - . ^ J , jy^^
On reaping machines. By A. S. . . ^ 45g
On horse language. By a Farmer. ^ . . i\^^
HORTJCULTURB. *
On the cultivatipn of crocusses, with a short account of jdifferent
speacs known at present By A, H. Hawort, Bsq. F. US. and
n. O. - _ _
461
Observations on the .culture of of the dahlias, in the northern parts"
?*!. ,?r^?"^*"' ^^- >» *^"^' to R- A. Salisbury, Esq. By
John Wedgewood, of Staffordshire, Esq, . .
Hints relatiye to the culture of the early purple brocoli, as practised ia
X?® J o ®" ^^ ^•°**^^ ^^^* ®^- *t Edmonton. By Mr. John Maker,
An account of the burr-knot apple. In a letter to Henry GrimstOHfl
esq. By the Rev. John Simpson. - ". ^^
On the horticultural management of the sweet or Spanish chesnut^ ^
tree. % tire Right Hoji. Sir Joseph Banks, bart, K. B.
On the proper construction of hot-bed frames. By T. A. Knight, esq.
X. Jtv. o. occ. - . , .
A short account ofa new apple, called the Do wijton Pippin. By IV
A. Knight, esq. F. R. S. - - . . 4^4
On the managementof the* onion. By the same. • " 4^5
An improved method of cultirating tl^e Alpine strawberry. BrUie
same. ' - . _ __ ' *
^'r^ S Tc""^"^*"^' ""-^^ ^^^^' ®^ ^' ^ ^^^' '^'
On the forcing houses of tlic Romans, with a list of fruit? c'ultiyated'
^^uIT^*''"' ^"^ ^^^ ^°"" °^ hpt-hoiisei. By thi ^ev. Ja^es Wil-"
4iS
ibid^
ibid.
467
ibx(t
CHEMISTRY ano MIipEim-QQT,
^emical expetiments on brazil and logwood, Bv Mr ChevMal • ah
On^the metals of potash and soda, ^Mek J^^l^^'^^n^ "^
Onthe action o^hosphonis and o|y muriatic acid'gas upon the alkaHcJ ^
By Mcwrs. BouiUlon, I^^nge, and Vogel.* ^ . . ,.
.,,--v,
CONTENTS,
On the double refrac^on of the crystals of sulphate of copper. By Mr.
Prieur. - - - - - - 9?
On th« manufacture of charcoal in close Tesselt, and on bringing into
, use the Various substances that are produced in the operation. Bj
Messrs. MoHerat. - - - - - HX>
On aconitumuapellus. By Mr. Philip Anthony Steinacher, - lOX *
.On Syrian asJcpias, as a ])lam that may be used instead of cotton.
. By Mr. Sonnini. . - . . - lOt
Kesearch^s and conjectures upon the formation of-metallic Electricity,
or ^h J is called galvanism. By B. G. Sage. - - lOS
'On a substance found in the island of Caprea. By Mr. Laugicr. - 10$
On a proeessi by which potash and sodamay be metallised without tlie
intermedium of iron. By Mr. Curaudau. * • - 106
Chemical expcriroejits on indigo and \road. By Mr. Chevreul. • 107
On the relation that exisis between the oxidation of metals and their
capacity of saturation for aeids. By M. Gay-Lussac. - tl3
Chemicalanalvsis of a black sand from the river Dee in Aberdeen.
•hire. By Thomas Thompson, M.D. - - - - 114
On • new kind of fusion, which explains the Formation of Lithoid
Lava. By Mr. De Dree. ' - - - -17%
On Arraconile. Bv Mr. Hauy. - - - - IXT
On Dusodile, a new Mineral 'Species. By Mr. Louis Cordier. - 178
On potashed Iron. By Mr. Hassenlratz. - ' - ' - ibid*
On the "Metals of Potash and Soda. By Mes-srs. Gay-Lussac and
Thenard - - . - - , ' * - 180
On Apophplite. By Prof R. J. Hauy. - - • 181
Oa the. tbrmaticiis in which Flint Slate is found. By Mr. J. J. Omft-
linsD'H^lloy. - - - - - 183
On artificial Puazo1?.na, oiTarras. By Mr. Gratien Lenere. - 18S
•Ixp'^rimentb lelative lo Pcta-h au<^ Soda. Py Mr. Kilter, - ibid.
Analysis of Scapelite, or Faranthine. By Mr. I^ugier. « 183
On tlie Chahasic, or cubic Zeolite, of the Island of Feroe. By Mr.
Vaunuelin. ------ 18f
On the Properties of the new Alkaline Metals. By F. R. Curaudau. ibid.
/ Description of a Process for determining the Existence of Alumiue in
the Stones which have fallen upon the Earth. By Mr. B. G.
Sage. ----,- i8g
• n the Unwholesomeness of Tea. By Mr. C. L. Cadet. ^ 18^
^Experiments on Sulphur, and on its Decompositlont. By Mr. Carau-
dan. - - - . - - 191
On violent Pickle, consii^cred as a Test liquor : and of salting Vege-
tables to preserve them from distillation. By Mr. Descroixilles>
the elder. - - _. - . . 19;3
On Chencvrx*8 experiments on Platina, and on those of Detcostils.
ByMr.C. L. Berthollet. -- - - - 194
On the existence of oxalic acid in the Leaves and Stalks of Rhubarb.
By Mr. bouillon Lagrange. - _ ' - _ 195
On the use of soda in the soap-works at Marbcillcs. By Mr. Lau-
ren?. - - , - - - - H9€
Observations on Cnraudau's experiments on Sulphur, and its Decom-
^» osition. Dy MeMrr. Vanquelin and Berthollet. ' - - 198
On the MiTjeralogicGeograpliy ol the neighbourhood of Paris. By
Messrs.- f'uvier. and Alcicrjuler Brongniart. - • 2t)f>
Improved Method of preparing Phosphorus bottles. - - 2<>6
Desf ription of an iroproved A ppacatus for the Decomposition of Potash
and Soda. By Mr, William Jon«3. - ' «.• . ibtd«
'«^ -^tSa^Kx
«•«
CONTENTl. Xlll
On a nrw Scvit for a Thermometer. By Mr. Richard Walker. n fOf
On Conserve of Grape, and iu AppUcataon to making of Wine. Bj
Mr. Parineutier. - » - • - • ftOI9
Observations on Caraudau*t Paper on the Influepce which the form of
fttills exercises on the products obtained, By liCr. BoqiUon La-
grange. - •- - t - ' - f^O
On Horse-Chwnut By Prof. Henry, of Paris. - - ftl
On artrticial Succinic Acid, Lampapias*8 sulphuretted Alkohol, Fe-
cula, and Cadet's aqueous Solution of Camphor. By Mr. Tromms-*
dorff. - - . . , - - ft3
pn a Composition of Ammonia. By Mr. Berthellet. r - 114
Pescription of a Method of fitting up in a portable Form the Elpc-
tric Column lately invented by Mr. J. A. De Luc. Also an
Account of seveiai experiments made wi)h it. By Mr. B. M.
Foster. ''.•'- ^- . ^ , ■ , fis
On the Acids produced by treating Qinger Root with nitric Acid.
By T. Le Gay Brewerton. - - - - S16
Chemical Analysis of a black Sand, from the river Dee, in Aberdeen-
shire, and of a Copper oAe, from Arthrey, in Stirlingshire. By
Thomas Thompson, M. D. - - - - - ibi<).
IN'ew Klactro-chemical Researches, on various Objects, particularly
the metallic bodies from the alkalies and earths, and on.some new
Combinations of Hydrogen. By Mr. Humphry Davy. - flf
Analysis of Auvite, Melanite, Staurotide, Labrador, Homiblende
shorlous Beril, reddish Moravian Tourmalme. By Mr. Klap-
wroth. -.•..» 2j|f
Analysis of some Minerals, known by the Name of Talc^ By Dr.
John. -'---- , fSt
On the Urine of Camels, and that of Horses ; and on the Uric Acid in
the Excrements of Birds. By Mr. ChevreuL - - fST
On the oxydizement of Tron. ' By Mr. Hassenfratz. - - f39
Oil the coagulatiun of Albumen by Heat, and Acids. By Mr. Thenard S4t
JKew process for preparing liquid Acetate of Ammonia, or Spirit of
Mindererus. By Mr. Destouches. ... f4j|
A continuation of the experiments upon the Decomposition of Sulphur.
By Mr. Cnraudau. - 1 - - - ^ f4S.
Aialysis of the Datolite. By Mr.Vanquelin. - - - 244
On the Diminution of the dilatability of Alkofapl in Thermoneten by
age. By Mr.'Honore Flaugergucs. - - - ibid.
Observations on the abov^ paper. By Mr. Cottp. - - ibid*
Additional observatibhs on the.above subject. By Mr. Honore Flau-
gergucs. - - - ... ibid.
Qii the Means of determining the Proportion of Acid and Base which
enters into the Composition of Sulptiate and AJnmine, and in those
of Sulphate, Nitrate, and Muriate of Potash. By Mr. buraudau. - t4^
Observations on Spiuellc-Pleonaste, orCeylonite, and particularly on
that found in the Neighbourhood of MontpelHer. By Mr. Marcel
de Serres. - - -■. .'- f 4S
On Nodules of Lava found in Clinkstone. - - - - 349
Remarks on the Report made by Vauquelin and BerthoUet respecting
the Author's two papers on the Decomposition of Sulphur. By F.
R.Curandao. -* '• - - " - 25(1
On the Construction and Effects of Pneumatic Tinder Boxes. By Mr.
Le Bovier Desmortier. - - ^ - . . 251
Qii making Syrup, brown or white Sugar from Grapes. By Mr. Focque. 254
Comparative Examination of AI^ Socotrina and Hepatlca. By Mr.
' Trommsdorif. ... r - - $$7
%l^
<;ONTSlfrf«
Pag*
Descrirtion of an Hjgroneter for Cases, and oftlioManne?of using it,
Bj M:. Gorton Morveau. .- - - - - 25%
Cb^pa '»tive Exaroiiation of Aloes, Gamboge, Buphorbimn, Myrrh,
Fia.ikincense, and Guui Ammoniac By Mr. Heurj Braconnot, -^ S5f
On Muriate of Tin. By Mr. £. Berard. . . , - f 69
Olbscrvations on Acetic Acid. By Mr. J. B. Molferat. . - 871
Jteport.niaoe bj a Committee of the Institute, on Mr. CurandaQ'sIast
Menx>ir. By Mr. Deyenx. - - - - 27S
On the Preparation of Uqaid Sugar from Apples or Pears. By Mr*
Dubuc. - - - ... g74
Analysis of three Vmds of Pyrites. By Mr. Bucholz, « • 276
Ona PowHersoId a$I{.eca6uanlia. By Mr. Henri. • * 277
Anatysis r f Biitis i and Foreign Salt, with a vievr (o their fitness for
economical purposes. By Dr. V\'iHiam Henry. • - ibid.
On the LoM of Weight which takes place in cooking Animal Food. - 28^
On the art of printing upon Stone. - , , . 284
l^aperiments on sccot'^rine and hepatic al( es. By Messrs. Bouillon,
Lagrange, and Vo;^^ 1. - , - - - - . 421
On cystic oxide, a new species of urinary calculus. By Dr. Wm.
^ Hyde Wollaston. - - '..'.". " *^^
Onoxyrauriatic acid, aod on the elements of muriatic acid ; \vith some
experiments on sutphur and phosphorus. By Mr. Humphry Davy. ' 4S4
Observations on the researches q£ Messrs. Gay-Lussac and Thenard»
relative to the amalgam of ainmonia, by Mr. Davy. > . 4S5
An examination of ^me observations of Messrs. Gay-Lussac and Tlie-
nard, on the facts relating to the metals from the alkalies, by ]\Ir. H.
Dary, . - - - - - -, 4$^
Qn potasb and toda prepared by means of alkohol. By Mr. Darcet. - 4^9
On the formation of acetic ether in tbe cake left in pressing grapei.
By Mr. Derosne. - - • - - - - 45 j
Kxanmiatioo of the supposed rice payte of China. By Mr. Klapwroth. 463
On brown hematites, and maiyh ore of iron, &c. - > 464
A reply to Ifessrs. Gay-Lnssac and Thenard's answer to the Analytical
Researches, &c. published in the Journ. dc Physique^ fpr December
1809. By Mr. Humphry Davy. - ' - - - 498
Answerby Messrs. Gay-Lnssac and Thenard. - - « 5Q0
On the change of potassium and fodiiun into fixed alkalies. By
Messrs. Gay-Lussac and Thenard. ... ^^
QMnucalexajitination of tlie indigq and woad plants. By Mr.
. Chevreul. - - - - - .. 506
On muriatic acid, ancj pxynuriatic ^fld. By Messrs. Tlienard and
Gaj^Lussac. - ... - §10
On the combination of gaseous bodies with one another. By Mr.
Qay-Lussac. - - • - •511
Chronological Ust of the meteors which have been succeeded by the
fall of stones or masses of iron. By Dr. E. F. F. Chladui. - 5t4
On pichbilende, an ore of Uranium. By Mr. Vauquelin. - • 51Q
pj^Mnription of Diphroitej a new species of mineral. By Mr. Louis
Cbrdltr. - - * . • « j^^
. ••t„
RETEOSIPECT
Of
PHILOSOPHICAL* MECHANICAL,
CHEMICAL AND AGRICULWRAL
I
DISCOVERIES.
snsBeateag
Ho. XXUl.] Janmry^ Fdtuary^ March. [1810. j
NATURAL PHILOSOPHY, ARTS, ax d MANUFACTURER
%letJiod of dividing astrmmicat and other InsintmenU, hy ocular
Iwpecivm^ in which the usu^l Tools for graduating are not etn^
phycd ; the whole Operation being so contriredy Jthat no Error
can occur but what u chargeable to Vision^ when asuisted by the
best optical means of viewing and measuring minute Quantities^
By Ma. Edward TttouGMTON. — Phil. Trans. Part L I8O9.
iVb conceive that the inerit of Mr. Trougbton's interesting, and,
\u a scientific point of view, innportant paper, on dividing astro-
nomical instruments, will be n^ost readily appreciated by a com*
parison with the methods previously employed for the same pur*
jose. We shall, therefore, first present our readers with aii
account of such as he has noticed in the introductory part of this
communication. ,
Bird, who was justly esteemed the most accurate divider of the
age in which he lived, owed his reputation chiefly to his contriv->
ance for rendering the usual divisions of the quadrant bisectional,
and the great care he took in* avoiding the unequal expansion from
change of temperature; His object wa^s to obtain a point upoa
t'he arc at the hiighpst bisectional number of divisions from 0^
-which. he effected b^ the assistance of a fidely divided scale of
ecuial parts': this, in his eight feet quadrants, was 1P24K85*^0^.
** The extent, of tb« b^am compasses, with which be traced the
arc upon the limb of the instrument to be divided, being set oft
^])on that arc^ gave the points Of. and So*: whichy bting bkected,
XO. 53,r— vol. VI. B
f Mr. Troughton's Method of dioi£ng oiironomkal ImtrumaUi,
give 30^ more to com|ilete the total arc. A second order ^f bi»
sections gave points at IS^ distant from > each other ; but that
which denoted 75^ was most useful. Now from the known
length of the radius, as measured upon the scale, the length of th^
chord of 10*^ 2(/ was computed, taken off from the scale, and pro*
tracted from 75^ forwards ; and the chord of 4° 40^, being ascer*
tained in tJhe same manner, was sjst off from JK)^ backwards, meet»
ing the chord of 10^ 3(/ in the continual bisections of S5* 2f/.
This point being found, the work was carried on by bisections,
and the chords, as they became^ sikiall eno4igh, were set off^
beyond this point, to supply, the Remainder of the quadrantal
arc. My brother, from mere want of a scale of equal parts
upon which he could rely, contrived the ^ means of dividing
bisectionally without one. Mis method I will briefly state,
m follow*, in the manner whtch it would apply to divtdtng m
mural quadrant. The arcs of So^ and 30^ give the total are, as
before; and let the last arc of 30*^ be bisected, and also the last
ttrc of 15% and again the last arc of 7*^ 3(/. The two marks,
next $0^ will now be S2^ 30^ and S6^ 16^ consequently the poiut
•ought ties between them. Bisections will serve us no longer ; but '
if we divide the space equally intil three parts, the most forward
of the two intermediate marks, will give us 8i°, and if we dividt
the portion of the arc between this mark and S6^ 15^ also into
three, the most backward of the two will denote SS"^ 25^ Last-
ly, if we divide any one of these last spaces into five, and set off
one of these fifth parts backwards from 85^ 25^ we shall have the
desired point at 1024 divisions upon the arc from 0% All the
rest of the divisions which have been made in this operation,
which I have called marks^ because they should be as faint as
possible, must be erased ; for my brother would never sufier a
mark to remain upon the arc to interfere, with his future -bisec*
tions."
Ramsben s well known method of dividing by the engine, Mr.
T. says, is capable of so much accuracy and facility, that its nst
will never be superseded for small instruments, to which it is a*
\oBfi applica<ble. And he ventures to predict; that the method of
HindeliQy, described by Smeaton, in the Philosophical Transact
tious fii^r 1788, will never be brought into practice for dividing
^Sttronomical instruments. Mr. Troughtein then continues :
^' The only method of dividing large instruments, now practised
lA j^oi^don, that I know of, besi4es my own, has not yet, I beKrve,
been made public. It consists in dividing by hand with beam
cowpassies and spring dividers, in the, usual wdy; with the addi*
tion 9f examining the work by microscopes, and correcting it, as
it proc^eeda, by pressing forwai^dsor backwards by hand, with a fine
'conit^ljpoint, those dots whicih appear erroneoai^; and thus d^ijust.
ing them to Uieir proper places, T^e method admits of consi&ritblt '
«'♦.
Mr* Trmf^aonlu M^fM 4fdmding ustrammkal InstrumentM* Z
•ccoracy^ providad the operator has a steady hand and a good
eye ; but his work will ever be irregular and inelegant. He must
have a circular line.passing through the middle of his dots, to en-
able him to make and keep them at an equal distance from the
centre. The bisectioi^l arcs, also, which cut them across, de-
fem them much ; uid, what is worse, the dots which require cor«>
section (about two thirds perhaps of the whole,) will become
larger than the rest, and unequally so in proportion to the num«
^T of attempts which have been found necessary to adjust them.
In the course of which operation, some of them grow insufferably
too- large, and it becomes necessary to reduce them to an equali*
>y with their neighbours. This is done with the burvusher, and
causes a hollow in the surface, which has a very disagreeable ap*
pearapce/' After some further remarks, Mr. T. adds, ^^ I will
now dismiss this method of dividing, with observing, that it is
iedious in the extreme ; and, did I not know the contrary beyond
a doubt, I. should have supposed it to have surpassed the utmost
limit of human patience."
In Mr. Troughton's method, which constitutes the object 6{
dis paper, the surface of the circle which is to be divided, as
vrell as both its inner and outer edges, particularly the latter,
jdbould be turned $a true as possible, and a little convex, hav«
4ngite radius of curvature not greater than one tenth of an inch*
The roller with which the primary divisions are effected, is a
littlexonical, baving the diameter of its upper edge, about '001 of
4an inch greater than that of its lower edge ; the one es^tremity
b^g too great, and the other too little ; so that it may easily ba
luljusted to that position where it will measure the arc exactly,
or tha( it may be carried several times round the circle without
the error of a single secoud. Experience taught Mr. T. that the
proportian between the diameters of the roller ^d circle should
.be that of 1 to l6, or that the former should make one revolutioi^
in the space of $2® 30^; and also that the roller should be divid*
ed into l6 parts ; the absolute equality of these parts is not an
easential requisite of the division. By this operation, the circle
will be divided into ^6 parts^ each of ^^hich will correspond with
an angle upon the circle of l"" 24^ SS^'' * 5, or one 256th part of
the circle. This number of principal divisions was chosen on
lurcount of its being susceptible of constant bisection. Two mi-
cioscopes are used for making the roller exactly measure the cir-
cle. In the action of the roller, when used to effect these prima-
ry divisiotis, there are two circumstances worthy of notice ; vif.
that the roller, in different parts of its journey round the circle,
measures it unequally ; and that, notwithstanding the inequality
of these divisions, it should make a second, third, &c. revoluttno,
without any sensible deviation from its former track. The for-
iOtr of Ibtse, Mr, T« accounts for, by the metal being more pa-
4 3fK Traughiants Met%oi ofiicidxiig astrpnomcd Ingtrimentiii
Tons in one part than in another, and illustrates iht coirrparatitt
densities by a ploughed field and a gravel walk ; the latter, he
thinks, arises from the mutual indentation which takes place in
the surfaces of the roller and circle. The inequality, however,
of these first divisions, is not of material consequence, as they da
not fall in with the ultimate divisions, which lire intended to b^
equal to 5^ each ; but it is of some importance that the dots be
all of the same size, concentric, small, axld round. They shoiild
also occupy a position very near the extreme border of the circle,
tti give them the greatest radius possible. The absolute atid
individual errors of the primary divisions are ascertained by th^
following ^ery ingenious method, which constitutes a principal
part of Mr. Troughton's invention.
■ " The apparatus (by which the 256 dots have been made)
must now be taken off, and the circle* mounted in thc^ same man*
ner, that it will be in the observatory. The two tfiicroscopes
which have ' divided heads, must also be firmly fixed to the sup-
port of the instrument, oh opposite sides, and their wires brought
to bisect the first dot, and the one which should be 1 80 ' distiiut.
'Kow, the microscopes remaining fixed, turn the circle half
round or until the first microscope coincides with the opposite
dot ; and, if the other microscope be exactly at the other ddt,
, it is obvious that these>dots are ISO^ apart, or in the true diap-
meter of the circle ; and if they disagree, it is obvious that half
the quantity by which they disagree, as measured by the divi*
sions of the micrometer head, is the error pf the opposite divi-
sion ; for the quantity measured is that by which the greater
portion of the circle exceeds the less. It is convenient to not^
these errors + or — , as the dots are found too forward or t^
backward, according to the number of the degree; and for the
purpose of distinguishing the + and — errors, the heads, at
mentioned before, are numbered backwards and forwards to fifty,
One of the microscopes remaining as before, remove the oth^ to
a position at right angles ; and considering for the present both
the former dots to be true, examine the others by them ; t. e. as
l^efore, try by the micrometer how many divisions of the head
the greater half of the scmi<circle exceeds the less, and note half
l^he quantity + or — , as before, and do the saine< for the other
semi-circle:. One of the micrometers must now be set at an
angle of 46^ with the other, and the half difference of the two
parts of each of the four quadrants registered^ with their respec*
tive signs. When the circle is a verticle one, as in the present
instance, ;t is much the best to proceed so far in the exaiivinatioa
ivilh it in that position, for fear of any general bending or
spring of the figure; but for the ej^amination of smaller arcs
than 45^, it will be perfectly safe, and more convenient to have
it horiaontal ; because the dividing apparatus- will then carry the,
Mr. Trougkian'^ ifhtkod efUMing iiatrmomical ImhymintH t
micrometers, severaf perfomtiont being madle in the plat»^^
the Hmb to be seen through at proper intervals. The niieroiW
ters must now be plated at a distance of i2° $(/, and the half
differences of the parts of all the arcs of 45^ measured and noted
as bef<yre; thus descending by biseetioas to 11^ 15^ 5^ $7^ ^(^^t
and ^^ 48^ 46^^ Half this last «|uantity is too small to allow the
micrometers to b^ brought near enough; but it will have tha
desired eflect, if tb/ey are placed at that quantity and its half,
J. f. '4^ 13' 7^^'5 ; in which case the examination, instead of
being made at the next, will take place at the aejct division but
one, to that which is the subject of trial. During the whole of
the time that the examination is made, all the dots, fxcept the
one under examination^ are, tor the present, supposed to be in
their true places; and Uie only thing in this most important
part of the business, from first to last, is to ascertain with the
utmost care, in divisions of the micrometer head, how much one
of the parts in the interval under examination, exceeds the other,
and carefully to calculate the half of their difference.
The preceding examination furnishes materials for construct-
ing a table of apparent errors, from which the. true errors are
next to be computed by the foUowihg rule : let a be the real error
of the preceding dot, b that of the fullowing ope, and c the appa-
rent error, taken from the tabl^ of half differences, of. the dot
* a- + *
under investigation ; then is -— 1- c its real error," When a
and b have both the same sign, their sum, bat when they have
different signs, their difference with the sign of the griiater is to
be taken, and the same for this new qnantity and c. Of this
kind of computation, Mr. T. has added some examples ; of which
the following is one :
For the point 45^ of the second quadrant«
Real error of the first point of the quadrant - . X 8*8 •
Real error of the last point of the quadrant • — 6*9
Half difference - - ^ - - , - X 09
Apparent error of the dot under trial ^ • — S'9
Real error - - - - • — 8*6
In this way all the errors are computed and arranged in a
table, which is to be used in dividing the instrument.
Mr. Trough ton having now completed the' first two sections
of h;s method of dividing ; vis. that of making the ^56 dots and
that of finding the errors of these dots and arranging thc^ in
tables ; he proceeds to a description of the remaining parts of
his apparatus for completing the true divisions : but for this des-
cription as well as that of othf r parts of the apparatus, we must
refer to the plates annexed to the original, from which it will be
mpch the best understood. We may observe, however, that in order
€ Mr. TfmgieoBS Mtiinpl of dividing^ 4u(tvii0mittiImermqfU*
^d obviate the diiiicuUy oiAWidmg the ruiier with a tiifiicieiit ex.
^Mtae&s to point out upon the limb of the instruinent «pacee corrcs*
p^pding to others previously divided upon itsdf, Mr. T* has rc^
course to a small sector. . '^ The radius of this sector is about four
times as great as that of the roller, and upon its arc are divided the
spaces which must be tranferred to theisstrument. One of the an*
gular spaces upon the circle will beequal to l6 times its correspond-
ing space upon the sectorial arc, or 20^ 30^; but this does not
leprefent any number of equal parts upon the instrument^ whose
subdivisions aVe to be 5^ each ; for is exactly l6j,
therefore so many divisions are exactly equal to a mean tpac^
between the dots whose errors have been tabulated. Let, tfaere>-
fore, the arc of the sector be divided into \6 spaces of 1° 2(/
eaeh, and let a similar space at each end be divided into eight
parts of ](/ each: w^ shall then have a scale which fumishea
the means for making the true divisions, and an immediate
examination at every bisected point/'
Having described the sector and other parts of the apparatus
to be used in dividing, Mr. T. next gives directions for their vse
in the operation ; and a]80 of the alterations that will be neces^
sary when the cirele is to be cfivided upon its edge, or a surface
at ri^ht angles to the usual plane of division. Mr. Troughtun
likewise subjoins a method of dividing a ciicle according to the
centesimal division of the quadrant, now used in France. " '* The
lOOP of the quadrant may be conveniently subdivided into 10
each, making 4000 divisions in the whole round. The 256 bt<»
yectional intervals/ the two tables of errors, and th^ manner of
proceeding and acting upon them, will be exactly the same as
before, until we come to cut the divisions ; and for this purpose we
must have another line divided upon the sector. For one 4000th
part of the circle being equal to 5^*4 of the usual angular mea-
1° 24^ 22^' '5
fg^fe , rz 15* divisions ; and just so many will
5*4
be equivalent to one of the intervals of the circle. The valu^ of
one of the great divisions of the sector wiU be 1° 26^ 24^^, and
that of the ^ parts, which are to be annexed to the right and
left as before, will be lO' 48''', therefore divisible by the engine.
Bothgraduations may also be applied. to the same ciicle with very
.little little additional expense, provided they be both effected at
the same time." An apparatus is likewise described by which
the same method of dividing is equally applicable to straight *
lines.
Mr. Troughton affirms that the efTects of temperature, during
the examination of the larger arcs of the instrument, are of much
greater importance than most workuien will allow ; and main-
tains, that, while this is effected it is absolutely necessary that
JfTr. Trougtai^hi Mtiktd of £vidwg ttitronomical rnstrummh* t
'^the wMe eirdc ftfaould be of the same beat exactly/' In conlir*'
mattoQ of this asaeriMm; ha obserrar, *' One d^ree of FahrMH
belt's thermometer indicates (o small a portion of heat, that, i»
8Qch places as workmen are usaally obliged to do their business
b, it is aot very easy to have three Cherniometers attached to
diffe^en^ parts of a large iostrameut^ shewing an equality of tenn
jierature within that quantity ; yet so necessaiy is cerrectaess an
this respect, that if a circle has libe vertex one degree wanner
than its opposite, and if this difference of temperatu>e be gHdm^
ally distribated from top to bottom, the upper serntcircle will
actually exceed the lower by Qf^ : and, if such should happen to
be the case while tlie examination pf the first dot of the liiiri
quadrant is made, the regularity of the whok opecation woul^
thereby be destroyed***
In offering a conoparative estimate of the different method itu
trodaced in the preceding parts of his papa*, Mr* T. remarks, ^ I
inow that thirteen dayis, of eight hours each, are well employed
in dividing such a cirtle by my method ; aboat fifty-two days
would be consumed in doing the same thing by Air. Bird's nne.
thod ; and I thii^ I ^cannot err much when i state the method by
adjustment, supposing every dot to be tried, and that two»thi«da
of them want adjusting, to require about one liundred and fifty o^
such days* The economy of time (setting aside the decided metuw
of accuracy, which the above estimate of its application ofiers to
view, wall, I think, be considered of no little mbment* By the
rising artist who may aspire at excellence, it will at least, and I
should hope, with latitude* be felt in the abbreviation of his la-
bours/*
Several other illustrations are given of various minor paati*
culars,i>ut for which we must reler such as are interested la the
Ittbject to the pa|»er iteelfi
Observaiiong.'^Thert are but few, if any, instances in whkh a
greater degree 'of science has been employed, or any mecham-
rd art cultivated with more assiduity, than in the division of as*
tronomical instruments ; and with what success, the comparative
accuracy of ancient and modem obaerv^tiboa is a sufficient testi-
mony. Hie history of this* art, therefore, becomes highly grati*
^ng, not only. to the artist an^' astronomer, but to' all who either
delight in the devdopement of truth, or are intorested in the pro-
gress dfastroDomical science: heoee^ previous to making any re-
marks relative to Mr* Troughton's n^eUiod, we shalljMida fewhia-
U^ricfal notites prior to -the time of Bird's invention.
It has beinasset^ted, and v/e believe upon good authority, that
tydbo Brahe and Hevetiuf graduated thm oinca instnimffnu, ■
S Mr* Troughtms Method of diving astronfifniCc^^ifistritmenfst
The latter of these astronomers published bis Mackina CaUstiflm
1673 ; and Dr. Hook wrote btis ammadveirsioas on that work, ia
' the following year«
In this last work th« author ba» given a minute description of
a quadrant, the divisions of which were formed^ and afterwards
read off by means of an endless screw^ working in the edge of the
limb, which, he says^ *^ dties not at all depend upon the care an4
diligei.ce of the instrument maimer, in dividing, graving, or imo)-
bering the divisions, for the same screw makes it from end to end/
The method the Dr. styled " an explication of the new way
of dividing f and adds that it " excels all the common ways of
division :'' from which it may be inferred^ that it was tbe first
attempt- to apply the endless screw and wheel or arcb] to
the purpose of forming tbe divisions on astronomical instru-
ments. The artist was the celebrated Mr. Tompion : but
this method was not found to approach so near to perfection a»
the doctor supposed ; for^ after a sufficient tiial in tbe conbtruc*
tion of the sextant with which Mr. f lahisteud made his obser.
vations at th^ Royal Observatory^ between tbe years I676. and
}689t it was laid aside, 'i'bis instrument is described in tbe
Prolegomena of the 3d volume of Historia Ccelestis, and the des-
cription is accompanied with a iigure. This section, was aft«r-
waiVls furnished with diagonal divisiuns, distinguishing tbe arch
into portions of IC/ each, but at first tbe screw divisions wera
alone depended upon. I'his additional improvement appears to
have taken place in 1 6*7 7*
In l689i Mr. Flamstead completed his mural arc at Green-
wich, in which he was greatly assisted by tbe ingenious Mr.
Abraham Sharp, his amanuensis^ who was chiefly employed in
tbe construction of thejciiural arc ; aad which, in the space of 14
mouths, he finished so much to tbe salisfactitm of Mr. Flam-,
stead, that he spoke of him in the highest terms of praise, lliis
celebrated instrument, of which a figure was given at tbe end of
the Prolegomena, .was of 6 feet 7\ inches radius ; and the divi-
sions were formed with great delicacy and exactness. About the
same time the celebrated Danish astronomer Olaus Koemer, laid
the foundation of his Observatory^ as appears from tbe account
given by Peter Horrebow, his historian, inserted in the work,
entitled Basis Astronomias, published in 174U In the same
tract there is also given a descriptioa of an instrument, which
not only answered the purpose of a meridian arc, but, a telescope
being mounted an its axis, it also furnished the first idea of a
ti*aiisit instrument. But it is the peculiar method which HQemer
used in dividing bis instruments which tdeierves the chief notice*
He began at a. given point, and set off tbe required number of*
equal parts in regular succession, t9 the extent of his arc* For
«if(^cting this with as. much accuracy aa possible, lie )kKtA tw<s
Air, Troug/Uon's Method '(^dividing astronomical Instrmnents. 9
Miff, but fia^ pointed pieces of steel, together, the distance Ik*
tween the points of which being equal to one of the i,ntended
divisions in the limb of tde instrunaent, and being l^lOth or
l-12th of an inch, would answer to about IC' on an arc of 2^ or
3 feet radius. These divisions were distinguished on the linib by
very fine dots, and the whole was properly numbered. The sub-
division of these arches of 10"^ each, was performed by means of
a double microscope, carried on the radius of thf instruoienty
having its common fociis furnished with parallel threads of fuigle
«ilk, eleven of which were disposed at ten equal intervals, ana
comprehended together one 10' division, the distance of the near-
est threads became a visible spate^ answering to one minute
each, and therefore capable,* of a much further subdivision by
estimation. Hence the divisions on this instrument were not
degrees and minutes ; but if exactly equal, they were capable ^of
answering the same purpose, when their true value was found oy
comparison with larger instruments. This method of division,
however, was not so susceptible o( being rendered accurate aji
that of Dr. Hook, by means of the endless screw.
Mr. Flamstead's instruments being removed by his executors,
when Dr. Halley was chosen Astionomer Royal, Mr. Grahanl
nndertbok to make a new mural Quadrant, about the year 17%5^>
Tbe division of this iiistiiiment he executed with his own hand,
and united in it all that was valuable in the different methods of
his predecessors; it was completed with a degree of contrivance,
accuracy, and precision, before unknown. What appears to be
peculiar to it was the adoption of an arc of S6 degrees iii
piefereoce to that of 90^ not only as a check on the arc of de.*
grees and minutes, but also as being susceptible of the more sim-
ple principle of continued bisection. He also rejected the subdi.
vision by diagonals, and substituted that by the vernier in its
stead ; and this not only rendered the observations capable of
being read off with all the precision of which the instrument
would admit, but likewise caused the two sets of divisions to act
as checks upon each other. Another circumstance peculiar to
the construction of this instrument was the adoption of the beam
compass for transferring and cutting the divisions from the origii^
nal divided points. Mr. Graham, however, does not seem to
have beea aware bow great an error may arise from the, unequal
expansion of different metals, by a variation of temperature ;*for in
both this instrument and the zenith sector which he constructed
for Dr. Bradley with so much care and skill, the radii or frames
were iron, but the limbs were brass. For some years prior to
the death of Mr. Graham, in 1751, the principal astronomical
instruments were divided by Mr. Sisson ; and there can be no
doubt but he was well acquainted M^ith Mr. G.'s method : it was
oQt of this school also that the eminent Artiit, Mr. Binly arose^
xo. 23,— vol. ru c
\ 0 Mf. Tfovghtofi^s Method of dividing astronomical Jnsitunienh,
That the are fixed upon bj 6ird, was the greatest in a qua-
drant which was capable of continual besection into portions of
5^ each, may easily be showp thus. A quadrant comprehends
9(f X 60^ or 90 X 1? = 168O divisions, each of which con-
tains 5^. Now as every bisectional number is evidently some
power of 2, the greatest power of this integer contained in 108O
inust be that answering to the greatest bisectional arc ; henct
1** =;: 103t4; consequently 10^4 -i- 12 = 85° 2(/ the iarc re-
quired.
With respect to the subject of this article, it will be considered
as both curious and interesting by many, while others will regard
it as highly important and useful ; and the artist in particular
teust feel himself greatly indebted to Mr. T. for his ingenuous
^communication. The advantJ^ges of this method are very obvi-
ous from Mr. T's comparative estimate which we have trans-
fecribed ; and on this head he also observes : " 'Ilie number
X>( persons at all capable of dividing originally has hitherto been
Very few, the practice of it being so limited, that, in less than
twice seven years, a man could hardly hope to become a work-
man in this most difficult art. How far I shall be considered
as having surmounted these difficulties, I know not ; but if by
the method here fevealed, I have not rendered original di-
viding almost equally easy, with what copying was before, I
have spent much labour, time, and thought in vain. I have no
doubt, indeed, that any careful workman who can dividfe in com-
mon, and has the ability to construct an astronomical instrument,
"Will, by following the steps here marked out, be able to divide it»
the first time he tries, better than the most experienced work«
man, by any former method." We freely cIjblss ourselves among
that number of individuals who not only set a high value upon
tHe integrity and accuracy which Mr. T. has so long exercised
in dividing instruments of this kind, but esteem that ingenuous-
ness and love of science which he has manifested on the present
occasion; and notwithstanding some slight objections which
might be urged against his method^ we are persuaded that it is
^e\\ calculated to facilitate the accurate execution of one of the
ilicest operations of manual labour.
We are also happy to observe that Mr. Trough ton's liberal
communication of his mode of dividing to the public through the
medium of the Royal Society, has gained him the compliment of
the Copleian medal from the council of that learned bpdy.
( n )
Vn an Improrement in the Manner of dividwg astronomical Insfni*
ments. By Henry Catendisii, Esq. F. R. S. Phii, Tram*
PartIL I8O9.
Ma. Cavendish's object in this communication is to reiQQyt
-the principal objection against dividing by the beam compa99 1
and this he thinks may be effected by employing a comp?iS6 witb
only one point, and a microscope instead of the other, which noay
be used without setting the point into the division, and conse-
quently the danger of bruising it ^ill, by this nieans, be completely
removed. In this method it is necessary to have a steady suph
port for the compass, and Mr. C. proposes a frame resting upon
the surface of the circle, when in^a horizontal position, ai^d made
to slide round it with an adjusting motion, in order that it m^' bf
easily brought to any required point. The beam comp«^sa turqs
about an axis, which passes through one of its extremities^ and is
£xed CO a point in the frame, without the circle, while the other
end containing the point rests upon a support that can hie easily
lowered, sp as to suffer the point either to rest upon the circle, or
prevent it from touching it, at pleasure. A microscope is made U>
slide from one end of the compass to the other. The distance
between the centre of the circle to be divided, and the centre
^bout which the compass turns, must be varied according to th^
magnitude of the arc to be divided ; it is therefore most c^Rve^
Dient that the piece which supports the centre d of the compaj^
should be made to slide nearer id, or further from the centre of
the circle ; but its distance from it should not be susceptible qif
variation by the motion of the frame. The end of the compass
conUinirhg the point, Mr. C. denotes by^; and observes, " this
being premised, we will first consider tne manner of dividing by
continued bisection. Let F and / be two points 00 this limbj,
which is to be bisected in ^. Take the distance of the microscope
from the point nearly equal to the chord of/^, and place d s^
that the point, and the axis of the microseope shall both be in
the circle in which the divisions are to be cut. Then slide the
frame till the wire of the microscope bisects the point F ; ap^
having lowered the support at ^, make a faint scrc^tch with the
point. Havipg done this, turn the beam compass round on th^
centre d till the point comes to D (another point in the limb pjf
the circle,) where it must rest on a support similar to that ^t i,
9nd having slid the frame, till the wire of the microscope bisects
. ^he point/, make another faint scratch with the point, which, if
the distance of the microscope from the point has been well taken,
will be very near tlie former scratch ; and the point midway
between them will be the accurate bisection of the. arch F f; but
it is unnecessary, and better not to attempt to place a point be-
tween these tvro scratches. Having by the^e n\^ns determiiie^
it Mr. CavmdUk's h^acemvU U dmUng aarmmkal Intfwnent^
the bisection at ^, we must bisect the arcs F ^ and f <p\n just
the same manner as before, except that the wire df the micror
scope must be made to bisect the interval between the two faint
scratches, instead of bisecting a point.".
When the arc to be bisected is small, a bent point is to be used :
«r recourse may be had to Mr. Trough ton's method of bisecting
an odd number of contiguous divisions. The bisections thus oh^
tained are not the real divisions, but only marks from which
these latter are to be cut. For the purpose of making the real
divisions, the microscope rnust be placed near the point, and d \
caused to become a tangent to the circle at J. " The wire of the
microscope must then be made to bisect onfe of these marks, and
a point of division cut with the point, and the process continued
till the divisions are all made." Some precautions necessary to
be attended to during the operation, are then added ; and it is
remarked that the entire arc of a circle cannot be divided to de-
grees without trisection and quinquesectiop : three methods of
performing the letter are subjoined ; the first of which is the
following : ** Let a '» be the arch U) be quinquesected.*, open th^
beam compass to the chord of one fifth of this arch ; bring the
microscope to a, and with the point make the scratch /'j then
bring the microscope to y, and draw the scratch e; and in th?
same manner make the scratches c^and6. Then turn the beam
coinnpass half round, and having brought the microscope to a,
make the scratch j9 ; and proceeding as before^ make the scratches
7, I ^nd f . 1 hen the true position of the first quinquesection will
be between h and /3, distant from & by one fifth of 6 0 ; and the
second will be distant from ^ by two fifths of dl, and so on.''
Mr. C then furnishes directions for subdividing these arcs, and
making the true divisions ; and enters into the calculation on the
comparative accuracy of the different kinds of division, which he
concludes as follows.
** It appears therefor^, that in trisecting, the greatest error we
are liable to, does not exceed that of bisection in a greater pro-
portion than that of 4 to 3 ; but in quinquesecting the error of the
two middle points is 2 J times greater than in bisecting. It must
be considered, however, that in the method of continued bisection,
the two opposite points must be found by quadrisection ; and the
error of quinquesection exceeds that of quadrisection in no greater
proportion than that of 6 to 5 ; so that we may fairly say, that
if we begin with quinquesection, this method of dividing is not
greatly inferior, in point of accuracy, to that of continued bisec-
tion."
As neither of Mr. C's other methods is superior to this in
point of accuracy, wo shall not describe them.
^Observatwns.^^ As we agree in the main with the observations
contained in Mr. Cavendish's concluding paragraph, we sha}|
/
I
Mr, Lax^ m examining astronomical Instruments. I $
transcribe it. He observed : " It is difficult to form a proper
jodgment of the conveniences or inconveniences of this method,
without experience ; but, as far as I can judge, it must have much
advantage, both in point of accuracy and case,* over that of di-
viding by the common beam compass ; but it very likely may be
thou^t that Mr. Troughton's method is better than eith«r»
Whether it ife, or is not, must b^ left for determination to expe-
rience, and the judgment of artists. Thus much however, may
be observed, that this, as wellas his, is free from the difficulty
and inaccuracy of settmg the point of a compass exactly in the
centre of a division. It also requires less apparatus than his, and
is free from any 'danger of error, from the slipping or irregularity
in the motion of a roller ; in which respect this method, notwith-
standing the precautions used by him, is perhaps, not entirely
free from objection ; and what with some artists may be thought
a considerable advantage, it is free from the danger of mistakes,
in computing a table f)f errors, and in adjusting a sector accord-
ing to the numbers of that table." With respect to the compari-
son here alluded to, between this method, Mr. Troughton's, and
that by the common beam* compass, there may perhaps be difl'e-
rent opinions. The superior execution of Mr. Trough con's work,
however, has decidedly shown the preference which his method
deserves over that by the common beam compass ; and we think
that '' future experience and the judgment of ai^ists" will also
prove its superiority to that proposed by the late Mr. Cavendish,
especially as this latetr gentleman's process requires the tentative
quinquesection of an arch.
* ■■.■■ IIIIM ■■ ■--- II II I II ll I ,11 . I II I
Oa a Method of examining the Divisions of astronomical Instrw
ments. By the Rev. William Lax, A. M. F. R. S. FhiL
Trans. Part IL iSOp.
At the commencement of this letter, Mr. Lax states some rea-
sons for the necessity and importance of this examination, and
then observes, that the instruments which he uses, for observing
both the altitude and azimuth, are' circles of one foot radius, and
divided into parts containing ten minutes each. The apparatus
by which he conducted this examination is next described. That
for the azimuth circle consists of an arc of brass, concentric with
the circle, and a little more than 90^ in length ; on this arc slides
a strong upright pi'ece of brass, bearing at its upper extremity a
microscope with a moveable wire in its focus, and inclined to the
left hand in an angle of about 30 degrees. '* The microscope has
attached to it, a small graduated circle of brass, and an index, by
which the seconds, and parts of a second, moved over by the wire
^re detern(uned." The apparatus for ^e vertical circle, it of a
} 4 itfr. L<Ufi <m ezimmng asironamkol Imtruma^i*
similar nature ; but some variations are nefceissary on account of
its position. The process of the examination is this : ^' The'first
point to be examined is that of 180^ which must be done in the
usual way, by bringing the points of 0 and 180^ to the moveable
wires of the opposite micrometers, and then turning the circle
half way round, and bisecting the points again with the moveable
wires ; and lastly, taking half the difference betwixt the wlVes, in
the two position^ of the circle for the error, at the point of 180^.
Having now bisected the point^of Zero with the moveable wire of
the micrometer, which is intended to be used in the rest of the
process (for we shall have no further occasion for both) we must
slide the microscope along the arc, till by moving the wire a little
we can bisect the point of 90^ and then the micrometer must be
firmly clamped to the arc. The circle must then be turned till
the point of 180° is brought to the microscope, and that of 90* to
the micrometer, so that we may be able to bisect each by a slight
motion of their respective wires. This being done, we must ob-
serve, from the position of the wires, how much the interval
betwixt them has increased Or decreased in the measurement of
the new arc ; and this increase or decrease must be noted down
with a -f- or — accordingly. In the same manner we must pro-
ceed through the remaining two arcs of 90°, observing and noting
dowh the difference belwixt each, and the original arc/' An arq
of 60° is next to be measured against every succeeding arc of 60°,
in the circle, exactly in the same manner that the arc of §0° was
measured against the other three. The arc of 4^° fnust then b£
measured with each succeeding arc of the same number of de-
grees, and this will complete all that is necessary to be done in
the early part of the njoraing, before the heat of the sun can hav«
affected the tennperature of the instrument. ' The rest may be per-
nor n^ed at our leisure.
This process is also to be continued to all the arcs of 30^, 15%
5% 3% 1% &c. and thence to all the divisions of the circle.
^' In order to ascerlain the greatest possible error to which ^e
are liable in the examination, let $ denote in parts of a second the
jgreatest ,that can be committed in bisecting any point upon the
limb ; then, since this error may occur at each end of the arc,
it 18 evident that e (the greatest error) in the expression deduced
above ( X^ P e ) will become 2 t, and the expression it-
»— .p 2 I
self X4 P e. Hence the possible error will be 4 1—2 f
n 2
2 c 2—^1 2
at 180° ;— -- -f -— - X4 I = ^ « at 90*^
2 • 2 ' ' 3 ■ 3
X4i = 3*33 « a^60»; J X 2 i + ^^ X 4 X 2« = 4ii
3
Mr. LoTf on examining a$tronomicai In$tnmeniSm 1 5
at 140^. The greatest error must therefore be betwixt 90^ and
130**, and nearer to the extremity of the latter than of the former
arc. At 105° it will be 5.50 1 ; at 111*' it will be 5.50 i — J.
1-4 f + -- — X 4 X 2 I = 9'70t ; and at 111° lO' it will
5
be 9*70 € — J. r04 f (the excess of the error at 111® ab'ovt
that ai 112**; +3*35 t rr 12*86 i, which will be foutid to be the
greatest error betwixt 105° and 120°, and of course the greatest
in the first semicircle. In the other semicircle, the process being
the same, the possible errors must necessarily be the same, at
the same distance from the. first point, reckoning the contrary
way upon the circle. The magnitude of the quantity e will of
course vary upon circles of the same radius, according to the ex-
cellence of the glass employed, and the accuracy of the examine/^
tye.''
There is, however,, very little probability that the error will
approach near to this extreme limit ; and its probable amount
may be greatly diminished, by bisecting the respective points
several times in the measurement of every arc, and taking an
arithmetical mean of the different readings^ jf for the true position
of the wire at the bisected point.
*' Of the time necessary for the examination, a prtetty correct
idea may be formed, by considering how many measurements are
required, and allowing about a minute and a half for each ; t. e. a
quarter of a ininnte for bringing the extreme points of tbe arc,
to the micrometer and the microscope, and a minute and a quarter
for making the several bisections. Now, in dividing tba whole
circle into arcs of 15° each, it will appear that forty-four mea*
suivments mast be performed, and to examine every point in each
arc of 15°, there will be 16 1 required, making in all 3908 mea«
iSurcments ; and consequently the time necessary for completing
the whole work will be 5^62 minutes, ot about 98 hours.
" By this method of examination, we ilaay guard against the
effects of unequal expansion or contraction, by meant of changes
of temperature ; and either entirely exclude any error, or render it
too small to be of any importance. Suppose, f^t instance, that
the arc determined by observation was 48°, then by measuriiig
it agftitist tlfe whole circumference increased by an arc of M°,
we sh^Il obtain a result free from any greater error of unequal
temperature, than one^eigbth of the increase or decrease of tha
arc of 24% beyond a due proportion to that of the circle itself.'
Ohertationsm — That an examination of this nature possesses
considerable importance in contributing greatly to the accuracy of
astronpmiical observations, without which they are of little value,
will be rendered sufficiently evident withoui^n>u£h reflectioii ; and
Mi;. Lax appears to have conducted the procest with laudable
'«€ peicriptim of a new cupping Ittitpment^
perseverance, ingenuity, and skill. By this means he has ret^.
dered bis simple instruments capable of answering all the ends of
the French repeating circle, and even of exceeding it in extent
of application. His comparison on this head is not unworthy
the attention of our readers, and is as follows ; '* This expedient
gives us all the advantages of the French circle of repetition, with-
out the inconvenience arising from being obliged to turn the in-
strument, and move the telescope so many times in^the course of
the observation. Nay, I am persuaded .that the result may bt
made more accurate in this way, than by the French method ;
because not only can the object be more frequently observed, but
the contacts or bisections, it may be presumed, will be more exact
when the observer is not disturbed by the hurry attendant upon
the use of the repeating circle ; and with respect to any error
in the instrument, from whatever cause it may arise, it will be
as eflectually excluded by the process which I recommend, as by
moving the telescope around the circle. Besides, this method is
applicable to either the azimuth or altitude, or indeed any circle
w)iich turns upon its own axis, whereas the French method can
never be applied to the azimuth circle, nor to any circle which
does not turn both upon its own axis, and upon one which is per-
pendicular to it.''
^•srss^mmmmmmmimmmmmnim^m
Description of a new Cvpping Instrument. By Robert HsAtf,
M. B.-^PML Mag. No. 142.
This cupping instrument consists of two parts: one of these is
a close vessel capable of holding about half a pint, made either of
very thin copper or tin, having a stop.cock soldered into it and
extending about half an inch within, for the purpose of prevent*
ing any liquid 'froni issuing from the vessel, when the cock is
opened. The other part of the instrument is a cupping glass made
in the 'usual manner, and adapted to the stop.cock by a coarse
threaded screw. The method of using the instrument is the fol.
lowing. The glass is to be unscre\yed, a little air drawn from
the vessel, and the cock turned to prevent its return. Some
ether or spirits of wine is then to be put in a wine glass, and the
mouth of the cock immersed in the liquid to such a depth, that
about a drachm of the liquid may enter the instruments The ves-
to! is next to be heated, to convert the liquid it contains into va-
pour, and then the cock being turned to prevent the influx of
the external air, it is to be immersed in cold water to condense
the vapour and form a vacuum, which may thus be obtained in
a few minutes. The cupping glass is next to be screwed into the
stop-cock, iuui applied to the wound o^ the lancet, &c. a&d
Mr. CoufeOe on t^c forabolic fjcns «/* ^p^gj^ 17
the suction reguUted by tuj^ning the ^ock; or if . necessary,
by unscrewing one turn of tne glass, and permitting the ail-'tb
enter the vessel through the thread of the screw.
Obsefvations.^-W e imagine that a dexterous cupper would per-
form his operation more conveniently and more economically by
the usual mode of deploying a spirit lamp or a little tow, ttan by
an apparatus of a more complicated nature. The idea of a secon-
dary cavity communicating T)y a stop-cock with a. cupping in« .
struuifnt, is so far from new, that it occuired nearly 2000 year^
ago to Hero of Alexandria, and a figure of fiis cbutrivance is ex. ;
hibited in the Mathematici vcteres.
On the parabolic Lens ^f Ruspini. Bi, Mr. Couteljle. ^Amu^i
de Chimiey vol, LXiX. i
THfs lens consists pf twf> pieces of glass, united together by a
hoop of iroii, so as to firm a vessel which will ho)d about tweii-
ty-one gallons of spirits • Its diameter is about 3 feet 3 inciies,
and its focal distance about j6 fee|; 4 inches. IThe effects of this
gl^ss are very great. Mr. Jacquin of Vienna, and some oft^er,
scientific men, who have witnessed them, say t.bat it burned a di-.
atnond in a fe^y seconds ; and fused platina in a few minutes, A.
button made of this iftetal^. which weiglved ^9 j^^P?> ^^s melted
by it, and made in part to boil. Its focus is ab9ut.4 irehch
lines in dianieter. • ^ ... .
The lens and necessary apparatus for placing th^ subject .of
experiment in a proper situation, are mounted on a strong frame ^
and made to move with the sun by means of machinery, regulated
by a seconds pendulum. Its whole weight is about p60 lb, avoir-
dupois, and wiien caused to incline towards either the east or
west, it requires a counterpoise to secure its stability.
J^bis lens is said to have been made at Gratz, in Styria, for
some alchemists, bv the celebrated mechanist wLose name it
l]|ears. It was made by softening the glass by means of heat> an^
bending it ove? a parabolic mould ; and as several pieces wer^
broken before the method succeeded, the original expense wa;^
bjBtw'een ,!^0* and 30 thousand franks, or between 800 and 1200
guineas. ^Ir. Coutelle purchased it for the f reach goverwenl
for iisbo florins) or 338/. sterling.
Observations, — Mr. Trudaiue has given an account^ ^ ibf
Memoirs of Xhe Parisian Academy, of a lens of similar cqi^
strupiipja to this which Mr. Coutelle has described. Its diametc^
waji It ffict, its focai length about IT; it conuined 140 pintib
probably Parisian, of spirit of wine* It must have been ntarl/
no. 23.— VOL, VI. D
Iti Mr. Telfirdrs Report on the Okeham and Boston CamU,
equal, if not superior to this, in power, its diameter being cotisi^
derably larger, although not quite in the same proportion as its
focal length. Mr. Parker's lens of glass, though smaller, seems
to have been more powerful, its surfaces having been probably
much more correptly formed : its diameter was 3 feet, its focal
, length 6 feet 8 inches,' and this length was generally still short-
ened by a smaller lens : it weighed 213 pounds.— Sc^ Young's
philosophy, lit 284-, 406, 407. Since the application of oxygei^
gas to the blowpipe, such lenses have excited much less curiosity
than they formerly pierite^.
sasB
J^emfrt of a new navi^abk Omalf proposed to be cut from Okeham to,
Stanford, and frofn'ihence to the to-wn of Boston, jBy Thomas
Telford, Esq. PhiL Mag. No 142.
' The town of Okehai^ being situated upon the summit of the
ridge of land which occupies that part of the copiitry, and from
which the adjacent streams dcsceud to the river Welland, affords
ail opjiorturiity of choosing diftereht lines for a canal navigation
to that river. The river Wash occupies the valley nearest to
the town of Okeham, anii as it possessed a sufficiently regular
descent for the required purpose, Mr. Whitwortb, in aforiper sur-
vey, was induced to prefer the course of that river for the Hne of
canal to Us junction with the Welland, about a mile and a half
below Stamford bridge., In this line an inconvenient circuity
must take place, before it could reach the town of Stamford, and
Its whole length from Okeham to that place would be about 19
tailes ; an^ *' in proceeding from the sea coast to the interior of
the country, the vessels navigating that line, must either pass at
the tlistance of about one mile and a half from Stamford ; or hav-
ing come up to the town, most return the same distance, on the
same line, to get into the valley of the Wash.*' These circum-.
Stances induce Mr. Telford to think, that this line should be
tibantloned, and another adopted in its $tead. That which he
how proposes, is to coqtinue the head \t\t\ along the above
mentioned line for about a mile and a quarter from Okeham, an(i
thence, instead of locking down the Wash valley, carry it through
Egleton into Gunthorpe, and afte:r passing the above valley, tO:
extend it through the ridge at Martinthorpe, into the valley of the
Chater. The line is then to be continued down the north side
df this valley to the most convenient place for crossing the river
WeHand below the place where the Chater enters it ; and thence^
iiividing as much as possible the high land from the low country,
t(» the river above Stamford bridge. This line Mr. T thinks will
\t shorter by 4 miks than the preceding one ; it will be more saW
itfr. Tdforfs Report on the Okeiam and Boston Canal. Ifi
t'tsfactory to the principal land holders in the county of Rutland,
it bears more equally upon the general population of that coun-
ty, and will more directly fix the intercourse by inland naviga-
tion through the town of Stamford. ,
. From Stamford the canal is to pioceed down the river Welland
for about three miles, and then depart from the north bank of
that river, and after separating the uplands and meadows, and
passing tt) the westward of I'allington, eastward of Barholm,
land to the west of Kate's Bridge, it is to enter the Car Dyke,
and be tamed alon^ that ancient work till it approaches the
iSoiith Forty-foot drain, which it is to enter opposite to Billingbo-
rough or HorBliogy and proceed along it to Boston. Mr.Telfotd
then enumerates several important reasons for preferring this
line olF inland iiavigation between Stamford and Boston to any
other; and obviated &ome objections which might be urgetl
against its adoption by the proprietors of other works, through,
or near which it '\t to pass. He then obsserves : ** In order to
render the inland navigation of this district of country, and the
cohbectibns with the interior districts more perfect, and to afford
a fair competition of local advantages, I am of opinion that a
canal should be carried between the Welland and the Nene ; and
the country appears to be particularly favourable for this junc«
tion. iThis line should depart from \M6 Welland precisely where
the branch to Boston does, and in a similar hianner thereto. It
should be carried in a line dividing the uplaild from the flat coun-
try, and terminating at oir near Peterboidugh. The country
through'which the canal would pass is very popiilou^, and requires
communication : ahd the towns and whole population of the val-
leys of the Welland and the Nene would thereby have an oppor.
tunity afforded them to benefit by the navigation o'f all the rivers
which fall into the great Bay — with the choice of sutH of therii
a& should best suit their interest and coriveniency.^'
The whole extent of the line embraces an inland navigation of
from 60 to 70 miles ; and as a great part of it would be carried
into effect at a small coinparative expense, it affords a fair pros^
pect of ample remuneration foi the adventurer^.
.... ,
bbiervatioits. — The canals already completed in this ( ountry
have produced great effects upon its culture and general state,
as well as upon its manufactures and internal commerce. These,
and the navigable rivers, render the cafriage of bulky articles
easier, and consequently compairati'vely lei^s expensive. The con*
veyance of manure, fuel, and several other articles' ihto districts,
into which they could not atherwise have been transported, has
tended greatly to the improvement of th^se particular tracts ;
and the ease with which the produce of the country can be tran^
milted to markets^ otherwise tee distant te lie reaeked, hae also
.J>
56 Kfr, Ttifor'd's tleport on the Okeham and Boston CauaL
liad considerable influenceon those markets, and greatly diminuhed
oad the number of horses that would be necessary for effecting this
transportation. It cannot, however, be denied, that in several
places in England, inland navigation has proved injurious to the
lands through which it is conducted, by obstructing the free pas-
sage of the rivers to the sea, and frequently overflowing their
banks, and damaging or destroying the crops in the low grounds.
Inconveniences of, this kind are sometimes much greater than any
coinraercial advantage that can be derived from the use of such
canals, except by a few individuals more immediately concerned
m them. Similar occurrences, however, may in general be pre-
vented by a more minute investigation of the consequences
that are likely to result from carrying this kind of navi-
gation into effect, and the expense of carriage greatly reduced
without endangering the best interests of the several districts
through which they pass. Mr. Telford's object in choosing the
present line of canal appeal's to have been not only to avoid any
inconveniences that might result from its execution, but also lo
render it as beneficial as possible to the adjoining districts ; and
this proposed line seexhs well calculated to serve both these
purposes.
It has been asserted, and we think very justly, that a general
canal-scheme would tend to equalize the price of every article m
different and distant parts of this country more than any other
means, and that canals, calculated for the navigation of boats as
small as ten tons would be beneficial for this purpose ; these
might be made at a v6ry reduced expense. In many of the
marsh and fen districts, most of the present seAvers would require
but little comparative labour to render them conducive to this
cnd^ and when a few of the principal ones were constructed, each
person possessed of extensive landed property would find it his
interest to make a smaller one through his estate, capable df
floating boats of about five or six tons. These would afford a
ready means of conveying both manure and produce from one
part to another, and therefore, not only promote the improve^
ment of general cultivation, but also greatly reduce the number of
horses necessai*y for agricultural purposes, and permit the land
required for their maintenance to be applied to other uses. Ca- ,
nals of this kind, we apprehend, might be easily executed in many
districtSv adjacent to this line from Okeham to Boston, particu-
larly in the lower parts of it. Mr. Telford's report received the •
approbation of the committee, who authorized him to proceed
with the surveys, sections, &c. for furnishing them with all ne-
cessary data for an application to Parliament for leave to carry
their plan into execution.
• •
( 91 )
On aerial Kavigati^. By Sir Gfioacs Cay^et, Bart* Phif,
. Joum. Noi. 112 ami 113.
The former part of this essay, descrilnng the general principle
of support in ai^ridl navigation, we ha^e already noticed, at page
427 of our fifth voliiiyrt ^ and the author's object in this continu-
ation is ** to sheir how this principle must be applied, so as to
be steady and tnanagisable." 1^6r this purpose, be first considers
the meatis of descent by the parachute, and shews that the com^
nion form of that machine, is nearly the worst pois&ible far efiect-
ing a steady d<tecent,' the end for which it was intended. He
also shews that the inverted position is that in which it should
be used for attaining the desired purpose. '^ This angular form
with the apex downward, is the chief basis of stability in aerial
navigation ; but as the sheet which is to suspend the weight at-
tached to it, in its horieontai path through the air, must present
a slightly concave surface, in a smail angle with the current *;
this principle can only be used in the lateral extension of. the
sheet; and this most effectually prevents any railing of the ma^
chine from side to side. Hence, the section of the inverted para*
chute, may equally well represent the cross seption of a sheet for
aarial navigation,*' The principle of stability in the direction in
which the machine moves, must be derived from a ditl'erent source.
If the machine be projected in a horizontal path, with a velocity
sufficient to support its weight, it will retain its relative position ;
like a bird in the act of skimming. '* The stability in this position,
arising from the centi'e of gravi^ being below the point of sus-
pension, is aided by a remarkable circumstance, that experiment
alone could point out. In very acute angles with the current, it
appears, that the centre of resistance in the sail, does not coincide
with the centre of its surface, but is considerably in front of it.
As the obliquity of the current decreases, these centres. approach,
and coincide when the current becomes perpendicular to the sail*
Hence any heel of the machine backward or forward, removes the
centre of support behind or before the point of suspensioa; and
operates to restore the original position by a power, equal to the
whole weight of the machine, acting upon a lever equal in length
to the distance the centra has removed."
From a variety of experiments which the author has made on
this subject, he conceives that a rudder, similar to the tail of a
bird, is' necessary both for the purpose of keeping the machine
steady, and for causing it to ascend and descend in its path« He
also observes that, ^* the elevation and depression are not the only
))tttpbBe8 for wnich the* rudder is designed. This appeniiage must
lM fsrnished with a vertical Sail, and be capable of turning front
aide to side, in addition to its other movements, which effects the
4!otli|pilet6 steerafge of the ves^l.'^
22 Sir George Cayley An aerial Naoigdtton.
All the preceding principles are stated to have been abundantly
verified by experiment, both upon a small and a large scale ; and
the only thing in this art Which remains - to be determined, is
the best niode of producing the propelling power. On thia
subject, however, Sir Geprge says he is prvparing to resume
his experiments. As conducive to the illustration of this subject,
he recui's to the flight oi birds, which be analyzes, taking the
common rook, as before, as the standard of calculatioof and eluci-
dating his reasoning by means of a diagram. Fiom the premises
on this head, he draws these conclusions : '* that very acute
angles vary little in the degree of resistance they make under a
sinnlar velocity of current ;*' and *^ that the act of flying, when pro^
perly adjusted by the Supreme Author of every power, requires
less exertions than, from appearance, is supposed."
It is then asserted that sufficient data have not been obtained,
, for determining the exact propelling power that will be necessary
for effecting the purposes of aerial navigation, and that the choice
rests between the direct beat, overtaking the current, like the
oar of a boat ; or one applied like the wing of a bird in some
assigned degree of obliquity. It is also concluded, that the ad>
vantage in favour of the latter method, if it could conveniently
be put in practice, is nearly as ten to one.
The author of this essay then states several mechanical diffi-
culties, which must be overcome before this art can be reduced
to practice ; but he. thinks that enough has already been done to
promise ultiipate success. The first of these difficulties is the
great power which must be brought into action before the nia-
chine attains that degree of velocity which is capable of support-
ing it, upon the principle of the inclined plane ; together with
the total want of all support during the return of any surface used
like a wing. The second im{>ediment is the great extent of lever«
on Bccouut of the distance of the centre of support in large sur-
faces, if applied in this manner. Another obstacle is the mecha-
nical skill which is requisite to unite a great extent of surface with
a sutficieiit strength and lightness of structure, and a firm and
steady movement in all its parts. With respect to the first of
these difficulties, it is observed that *' there appears several ways
of obviating it. ^ There may be two surfaces, each capable of sus-
taining the weight, and placed one above the other, having such
a construction as to work up and down in opposition when tkey
are moved, so that one is always ready to diescend, the moment
the other ceases. These surfaces may be so made Iby a valve^like
structure, as to give no opposition in rising up, and only to resist
in descent.** Rotative flyers, or a number of small wings instead
of large ones, may also be used ; or light wheels may be employed
to preserve tha propelling power, till it has dofficiently accwm^
lated Co elevate the machine. With respect to the great qnantity
^power thai wili be requisite at 6rst> it is observed tlwt amaa
Sir George Cayletf on aeriai NaxdgatioH. ft$
can exert more power for a few seconds, than twelve men can be-
stow for a continuance. And it is then added, '' If expansive
firsi movers be n>ade use of, they may be so constructed, as to be
capable of doing more than their constant work ; or their power
may be made to accumulate for a few moments by the formation
of a vacuum, or the condensation of air, so that these expedients
may restore at one time, in addition to the working of the en*
gine, that which they had previously absorbed from it." The
length of leverage may be counterbalanced by any elastic agent
which is brought to oppose it ; such as a spring or a cylin-
der, with a bag piston. Another prmciple that may be applied
for this purpose is, a construction for causing the air to counter-
balance itself : this method is then illustrated by a figure* A
third principle for this purpose of avoiding leverage, is by a mo«
lion parallel to itself ; and a fourth is that of placing the hinge
much below the plane of the wing ; or these two methods may
be combined and carried to any extent. '* A fifth mode of avoid-
ing leverage is, by using the continued action of oblique horizontal
flyers, or an alternate action of the same kind, with surfaces so
constructed as to accommodate their position lo such alternate
motion ; the hinge or joint being in these cases vertical."
Sir George then describes a wing which he had constructed,
for overcoming these general difficulties, and adds; " This fabric
contained 54 square feet, and weighed only eleven, pounds. Al-
though both these wings together did not compose more than
half the surface necessary for the support of a man in the air, yet
during their waft they lifted the weight of nine stone." The
means of communicating motion, and the importance of avoiding
resistance are next considered ; and it is concluded that a man
in the posture of sitting to work oars probably receives less pn^-
portional resistance than a crow in the act of flying. This inge-
nious writer coasidert it ''of great importance to th's art, to a^
certain the real solid of least resistance when the length or breadth
is limited." Newton's beautiful theerem he thinks of no practical
vse in this ease ; and he offers some remarks relative to the mpde
of considering the problem, with a view of exciting the atten-
tion of those who are more competent to its solution. It is con-
sidered that the shape of the hinder part of this body, is as im-
portant as the. fore part in diminishing resistance ; and Sir George
thinks that the moat useful way of ascertaining this figure is by
experiment ; and the surest path to pursue in this investigation
is to follow nature ; he therefore proposes to instance the spindles
of the trout and woodcock in a future communication.
Observations. -^Th'is paper is a continuation of that which we
noticed at page 427 of«ur fifth volume ; and as this essay is not
completed, we shall only offer a few observations of a general na*
Hire. Tlic fundfMacntal principles of ^erostatiop hi^ve been long
24 Sir Giforge CayUy on aerial NavigatiDn*
and generally known, as well as several speeulutions relative ta
the theory of it; but the successful applicatiou oi: thcde priocipliis
to practice is entirely of modern date* I'he rapid progress which
has be^n made in this art, by ihe iew who have employed th^rn-
selves on the subject, and the degree of perfection which it has
now attained, ought to be regarded rather as proofs of what may
be done, than as the consunimatiou of what may bfs expect*
ei. The nnsucces^al attempts which have been previously
made to render aerial navigation serviceable to tnankind, ought
not to furnish any argun>ent tor its discouragement ; while the
reflection that many arts aild sciences, from which so much be*
nefit it now derived, were long in attaining maturity ; that tUi»
resulted only fVom patient investigation, and reiteoiud experi-
ments ; and from our acquaintance with the ingeniiity and perse^
verance of Sir George Cayley, we have some reason to think that
the undertaking has fallen into good hands.
We agree with Sir George, that it wpuid be oi great importapce
to have the solid of least resistance accurately determined. New-
ton's determination, though true with respect to light, he thinks
Is not so relative to air ; each particle is supposed (q hav« free
egress after it has struck the body, which cannot actually teke
place in nature. The same objectieo may aiso he urged ^g^iost
most of the other inquiries on the subject. M* Bougu^r, in ^
paper published in the Reyal Acadeny of Sciences a^ Peris, has
solved this problem in a very geeeral manner, witboflt luippo^i^g
it to be generated by the revolution of any figure whatever, fh^
problem as enumerated and solved by him is this ; Any b^e bf ing
given, to find the solid that must be formsd upon it, so that
the impulse upon this solid may be the least possible. |t
should, however, be the retardivf force, or the i^npulse d*«
vided by the mass, which ought to be the mijoimmn- It
would also be proper to investigiste that form which yvould af-
ford the least possible resistance to a body containing a given
quantity of matter ; this consideration being applicable to the
case of a body advancing by means of its own iRom^tua^
only.
We conceive the subject to be such as to justify oiur tra^scrib*
ing the following remarks on the resistance of fiuids from I)rm
Young's Natural Philosophy, voU ii, page USQ ; and particularly
so, as that work may not yet be in the possession of niiany of oar
readers.
** The first approximation to a detemunetionof the effect ef thf
resistance, to a body of a given section termieated by ohliqii^
planes, is to suppose each particle of the fluid to impinge once oa
the surface, and then to retire for ever : on this soppesiUop .the
resistance ought to vary as the square of the cosine of the iftg]!^
of incidence. Another part of the resistance is occasioned h^ thfi
adhesion of the particles of the fluiil ; thb nej be tupf os^ ti>
Sir Gtorge Cayley on aerial Navigation* $5
vary, as the product of tht secant and the sine of tbt angle of in-^
cidence ; that is, as its tangent. This portion appears, in fact, to
be but small ; it may however, be taken into consideration, in order
to facilitate the computation. A third part depends upon 'the
form of the posterior surface of the body, and upon the unknowri
irregularities produced in the motions of the particles of the fluids
by the difference of the forms of its anterior part." It may be ex-
pected, that the negative pressure will be nearly uniform, when
the shape of the posterior part of the body remains unaltered.
Mr. Romme has remarked, that the facility with which the par-
ticles of the fluid can escape before the moving body, is propor-
tional to the angular space of the fluid which remains open to
admit them, and that therefore the resistance must vary in pro-
portion to this angle. Without allowing the tf uth of the obser-
vation in its whole extent, we may with propriety inquire, whe-
ther or not the portion of the pressure derived from impulse may
not in part depend on some simple function of the angle of inci-
dence ; and whether the whole resistance to au oblique surface
may not be considered as composed of a constant portion, a por-
tion varying with the tangent pf the angle of incidence, and a third
portion proportionate to. the square of the cosine, diminished in
the ratio of a power, or other functipn of the angle of incidence.
And it will appear upon inquiry, that if We take one fifth of the
radius, increased by one twenty-fifth of the tangent, and add to it
four-fifths of the square of the cosine, diminished in the ratio of
the circumference of a circle, increased by the angle of incidence,
to the simple circumferencCj we may approach always within about
One-tiftieth, to the number expressing the oblique resistance, until
the angle of incidence becomes greater thati 80°. Thus, the di-
rect resistance being unity, and a the angle of incidence, the ob-
lique resistance will be -^-f .0 4 f . a + 288 (cos. a)* : (SSQ+o'^.
A formula, somewhat more accurate than this, deduced from ex-
periment only, is r-z (cos. a/ -|- -000000421 7 a'** ; the quantity-
added to the square of the cosine being a little less than the
millionth of the cube' of the angle of incidence, expressed in de-
grees."
With respect to the direct resistance to a sphere, the same au-
thor has observed, that if we divide the square of tht velocity in
a second, expressed in feet, by l600, we shall have the resistance
with tolerable accuracy, in pounds avoirdupois, for a sphere afoot
in diameter, vol. i. p. 306. Now for a buoyancy of 200 pounds^
-we shall require a sphere of ai least 20 feet in diatneter, tht re-
sistance to which will obviously be 400 times as great as to a
sphere one foot in diameter : and if this sphere be required to be
propdlcd with a velocity of ten miles an hour, so as at least to
remain stationary in a gentle breeze, or as Mr. Rouse calls it, " a
pleasant brisk gale," the velocity being 14$ feet in a second, wt
NO. 25.— VOL. VI. B
26 Mr. Newton'^ Machine for chopping Aoots, 3f(f*
400
bave 215 for its square, and 215 X coo^^ 54 pounds. Now £l
labourer, working without disadvantage, can only exert a force of
about thirty pounds for a length of time, with a velocity of 3 or
4 feet in a second ; and if it were required that his relative velocity
should be ten feet with respect to his fixed point of resistance,
his force must be reduced to about 12 pounds ; and in order to act
upon the air, the relative velocity must become still greater ; so
that with the utmost mechanical advantage, it must require the
labour of at least five men to keep the balloon stationary in such
a breeze, and probably at least tep if acting against the air only,
while its buoyancy would only be calculated to raise one of them.
Undoubtedly the force of birds is applied under circumstances far
less disadvantageous ; and there is no reason to think it abso«
lately impossible that at some future time, a man, with the assist-
ance of a small balloon, may he able to make bis way very tole*
t'ably through the air, at least in calm weather.
Machine for Cutting Roots for Cattle, Jrticlcsfor Dyers* use, or for
culinary purposes. By Mr, Thomas Newton. Trans, iiociefy
of Arts y vol. XXVII ^
In ttiis machine tfie ii>eat is ()ut into a wooden trough, which
is the segment of a circle, fixed upon a triangular frame that is
supported by four legs, about the height of a common work bench.
A short iron axis is fitted to that angle of the frame which is the
centre of the circle of which the trough is a segment ; this axis
is forked at the top, forming a joint to which the end of a lever is
fastened, having fi\^ knives attached to ity by which the meat is
chopped. The ends of two pieces of wood are fastened to the iron
axis by the centre pin of the lever; to the other ends of these an
iron plate is fixed, which rests upon the edges of the trough, is
perforated with five narrow openings to receive the five knives fix-
ed to the lever, and acts as a scraper in clearing the knives from
the meat which would otherwise adhere to them. Two small up-
right pieces of wood are fixed into those connected witti the iron
plate, and the knives are prevented from being lifted quite out of
the openings of the plate by means of a pin passing thiough these
two pieces. A spring is fixed to the axis, and exerts its force
against the under side of the lever, and assists in raising it after
the stroke. As the lever is capable of revolving horizontally about
its axis, the article in every part of the trough is exposed to the
action of the knives. The knives are fastened to the piece of
wood on the lever by bolts passing through them close undei' and
above the piece to which they are fixed, and when any of them
want grinding, they can easily be taken out and replaced. The
^i^ottom of the trough is fastened by screws, so that when it is
M/-, Brockbank*i Machine for making Slate Pencils. 27
\yorn by the action of the knives, it can easily be taken out and
* planed fiat. The length of each knive is equal to the breadth of
the trough.
The advantages of this machine, are stated to be a saving of
labour, time, and waste of meat. And it is added, that " the spring
raises the knives, and enables any person to chop at least twenty
times as much meat in the same time as can be done by the com-
mon mode." ^
Observations,-^ \ very slight inspection of this machine will be
sufficient to evince its utility. It is well adapted to effect a con-
siderable saving of labour, particularly in preparing sausage meat;
yet w« think that Mr. N. over- rates its advantage in this respect,
by"his statement at the close of the preceding account.
'«■
Machine for making Slate Pencils. By Mr, J. Brockbank,
Trans, Society of Arts, vol. XXV II.
Motion is communicated to this machinery, by the revolution
of a small wat<r wheel, on the axis of which cams are ^xed for
effecting this purpoee. The upper jaw of a pair of pincers is firm-
ly fixed to a post, and the extreme part of the lower jaw is con-
nected with one end of a heavy lever by which the pincers are
opened ; one of the cams fixed on the axis of the wheel, presses
upon this part of the pincers in its revolution, and closes them, by
which means the materials are split into slips or lengths, and pre-
pared for the next part of the process. The pincers are thus open-
ed and closed alternately, by the weight of the lever and the mo-
tion of the cam. Another cam fixed to the same axis, imparts an
alternating horizontal motion to a frame which rests upon the
general frame of the machine, and impels the pencil through the
cutter, which is effected by means of chains connected with a wedge
and wheel placed upon another axis. The cutting instrument con-
sists of a tube made sharp at one end, somewhat resembling that
with which sadlers punch holes in leather. This tube should be
made of good steel ; and after the pencils have undergone this ope-
ration of passing through the tube, they are passed through a se«
Qond to reduce them to a proper size for use.
■W"
Observations. -^The nature of this species of manufacture is suchj
that on a superficial view it may, perhaps, appear to occupy so
humble a place in the scale of importance, as to have little claim
to the attention of the public ; but we are persuaded that a more
intimate acquaintance with the subject, will evince this to be
much stronger than might at first be supposed. The demand
for pencils of this. kind is certainly very great, extending almost
to every village in the kingdom. This demand has hitherto been
2S Mr, Broclibank*8 Machine, for making Slate Pcncilff
chiefly supplied by importation under the name of Dutch pen-*
cils ; and considerable sums have annually been remitted Iroin"
this country for their purchase. Hence any contrivance for sup-?
plying this consumption from internal sources, becomes an object
of some consequence, even in a natiohaK point of view; as it nCC
only renders us more independant of foreign connexions for an ar-
ticle which is in constant use, but opens a fresh* field for the ex-
ercise of British industry, and brings a greater capital into home
circulation, instead of transmitting it to foreign countries; and,
therefore, as the materials can be considered as of liitle value, the
invention ought to be regarded as tending to effect a national saving,
tiearly equal to the whole priinecost of this article. It appears let
have been Mr. Brockbank's object to invent some mode of hianu-
facturmg this sort of pencils, which should , render them equal in'
cheapness, and superior in other respects, to those obtained from
foreign markets, When the cheapness of the imported pencils is
considered, this does not seem an easy task ; yet hjs, having been
induced by the sale of this article to caus6 the machinery for its
manufacture to be wbrked by water, which was at first only put
in motion by hand, is g. sufficient proof that he has obtained the
former of these objects, and the manner in which this is accom-
plished, leaves no voom to doubt that the latter has been as com-
pletely surmounted. The Society rewarded Mr. B. with fifteen
guineas for this commuication. '
Machine for manufactunng Silk covered JVire, and Thread covered
with Silk. By Mr. Thomas SadAnoton. Trans, Society of
Arts,'9ol, XXVIL
Mr. Saddington's design in the invention of this machine, was to
remedy three material inconveniences, which attended the common
mode of covering wire, v\2. First: The necessity of having work*
shop^ in gener:al from twenty to forty yards long, consequently the
purchase or rent of such premises in London must be very consi-
derable to the manufacturer. Secondly : The disadvantage of
having the, wire cut into pieces of the length of the workshops,
for the purpose of covering it. Thirdly : The irregularity of the
work so made, unless performed by a very steady hand. All the
^bovc inconveniences are fully obyiated in the present invention ;
as the machine may be worked in a small room, and the wire
may be covered of an entire length bf several thousand yards, if
required, with a certainty of its being regular throughout the work.
Besides these advantages, it requires only one person to work it,
whereas in the common mode, two are absolutely necessary.
These objects, Mr. Saddington effects by a judicious combination
of wheels, conical pulleys, spindles, rollers, levers, and werghts,
iixed iu a proper horiBont«^l anci rectangular frame. This ingeni'p
3/r. Saddmgton's M^chinc/or covering iVire. ^.
€us contrivance, however, is too complicated to admit of a per-
spicuous description without its being more extensive than our li-
rnits wfll allow ; we must therefore refer such of our readers as are
interested in matters of this nature, to the original communication
and descriptive drawings, or to an inspection of the model, which is
preserved in the Society's Repository. Mr. S's description ',)fthis
machine is aocompanipd with a table for regulating the numbers
of revolutions in one inch of wire, and with certificates from seve-
ral gtntlemen engaged in this kind o I manufacture, expressing their
great approbation of the machine, the novelty of its principle, and
the accuracy of its work ; and tlie Society rewarded Mr, Saclding-
ton's ingenuity with a premium of thirty guineas.
Methods of raising the Bodies of Persons re ho havesujfk under Watery
or of assisting Persons in Danger in Water, Bt/ John Millir
Esq. Trans* Society of Arts, vol. XXVII.
In this communication, i\Ir. Miller describes three machines
of his invention, for efFerting these desirable purposes, with the
mode of their application. That which is intended to be used
in raising the bodies of persons who have sunk under water, consists
of a round piece of deal, aboi.t ten feet in length, and two inches
and a half in diameter. At thirteen inches from each end of this
bar, a square piece of deal is fixed, and made firm by a bracket.
From this bar four pointed drugs are siispended at equal distances
from each other. Each of these drags is loaded with two pounds
of lead fastened to the lower end of its shaft or stem, for the pur-
pose of steadying it when in use, and preventing its points from
entering the ground. The opposite effects ot the bar, and these
weights keep the drag in a proper position when in action. Each
drag has a swivel at each end of its shaft, anS its whole length is
about nineteen inches. About the middle of this shaft, are fixed
three hooks^ which are subdivided at eight inches from their ends.
^* The} are curved, ahd their points when turned up again are
abnut four inches below the level of their tops, and thirteen inches
Asunder; and the outside point of each subdivision, is thirteen
inches from its adjoining one. The extreme points are split, and
formed into a double hook, very sharp, and pointing towards the •
stem." When suspended from the bar, the hooks of each drag are '
within about five inches of each other ; those at the ends are lar-
ger than the others. The drawing rope passes through the swivels
of all the drags, and through each end of the bar, at the outside of
the pieces of wood perpendicularly fastened to it. It is then made
fast by means of wooden wedges, in such a manner, that the two
•nd drags may be suspended a few inches below the ends of the
pieces of cross wood fixed' to the bar: the other drags are also
fixed at the eame distance from the bar. All the drags are madcf
so Mr. Millers Methods tf raising the Bodifs
fast to the drawing rope, at equal intervals from each other, and
prevented from entangling by means of bored pieces of wood
of equal' lengths, placed between each adjoining pair of drags,
on a rope which passes through their bottom swivels. The drag^
thus fixed in their proper positions have a free rotary motion ; and
-being separated from each other, only by what will give way, arc
^ rendered as undulatory in their progress, as the bottom af the wa-
ter where they are used. For the purpose of either drawing the
whole apparatus backwards, or releasing any of the drags which
may happen to get entangled with any object at the bottom of the
water, another bar of equal lengtli, hut ot less dianfieter than that
to which the drags arc fixed, is attached to their lower swivels by
ropes of a proper length. Directions are given for its use, aniJ re-
lative to the state in which it should be preserved in readiness, or
conveyed from, one place to another ; and it is also added, that the
expense 0/ this apparatus is three guineas.
Mr. Miller also describes two other machines of his invention,
as closely connected with the subject of life preservation : the
former of these, he calls a Reel Safegvard, and the latter a Missile
Hope, The first of these consists of about thirty-five yards of line
made fast at. one end to a reel, which is about fix inches in dia-
meter Bnd ten in length". The other end contains 4 ring large
enough to admit a strong strap to pass through it* Two straps of
strong Sadler's web, two inches wide, crossing each other, ^.re
well sewed together, just above the pit of the stomach, and after
leaving sufi^cient space for the arms to pass through^ the ends on
each side are fastened together. A ring is fastened to the ends
behind the left shoulder, and a buckle and strap eighteen inches
long, behind the right shoulder. This strap is to be passed through
the ring on the end of the line, and that behind the left shoulder,
and then buckled to the size of the wearer. By this means, when
it is usedfor drawing a person out of the water, he is kept on hia
hack, and his head above water. I'he cost of this apparatus \^
eight shillings and sixpence.
The Missile rope consists of a similar line rendered buoyant by
means of pieces of cork fastened to it at intervals of three or four
feet distant from eacli other. It is made fast at one end to ^
wooden reel, of a proper size, on which it is to be kept woui.d in
readiness for use. The throwing end is made fast to a piece of
wood, shaped like the but end of an oar. It should be unwound
before it is thrown, that the corks may not be an obstacle to its
running off the reel in the throw. The cxpence is stated at seven
shillings and sixpence.
Observations — On the important subject of both rescuing per-
sons who are in danger of drowning, and raising the bodies of
such as have unfortunately sunk under water, a variety of info r-
of PcrsoTUi sunk undi r IVatcr. Si
feiation may be fuund in the different volumes of this work. Dr
Cogan's drag has been described at page 7^ <^f volume iii ; which
has for some time past been ehleemed the most efficacious utauy
in use ; but this drag only exteuds over a space of about eighteen
inches at one sweep, and therefore requires a considerable time t6^
search a large space with certainty. What is denominated the
bar drag, though of greater extent, is incapable of accommoda-
ting itself to the unevennei^ses in the bottom ; and consequently
tvlien hollows occur, these remain untouched, though the most
likely place for the object to lie. It is also an obvious fact, that,
on these melancholy occasions, any means, to be effectual, must be
expeditious ; and it was with this object in view that Mr. Miller
exerted his ingenuity in devising the present apparatus, for which
he has obtained the gold medal of the society of arls, and merited
the. thanks of the public. This machine is expeditious, because ex-
tensive, and secure because the pliableness of its materials adapts
it to an uneven surface. Mr, Miller's other contrivances, also ap-
pear ti) be well calculated to answer the intended purposes.
As accidents of this nature frequently happen, and often prove
fatal, itls to be feared, for want of proper treatment, a few general
remarks on the subject will not be improper. It is certain that in
drowning there is very often such a suspension of the vital powers,
as has every appearance of their total extinction; yet they may be
again set in motion, and the person restored to life, after a much
longer submersion than has generally been thought capable of
producing absolute death. The length of time that a person may
remain under water without being drowned, is very unequal willi
different individuals; and depends upon the temperature of the
water, as well as on the particular constitution of the sufferer : in
general, however, there is less prospect of recovery after an im-
mersion i)f fifteen minutes. In sueh cases death ensues from im-
peded respiration, and the consequent cessation of the circulation
of the blood, by which the body loses its heat, and, with that,
the vital principle. Dr. Goodwyn observes, that the water pro-
duces all the changes which take place in drowning, only indirectly,
by excluding the atmospheric air from the lungs, as they admit
biita very inconsiderable^ quantity of fluid to pass into them, du-
ring immersion. Hence, the inflation of the lungs is one of the prin-
cipal means of restoring life. It is, however, a very common and
dangerous error, and one which deserves to be particularly noticed,
to suppose that p«rsons apparently dead by immersion underwater
are irrecoverable, because life does not soon reappear. We there-
fore seriously intreat those who are employed m this act of hu-
manity, to persevere in the application of the most approved reme-
dies recommended by the Humane Society, for three or four liouii
at least ; for there are many instances on record of sufferers liavin^^
32 Mr. Williains 8 Method of securing tie Beami of Ship^.
recovered after they had been relinquished by all their medica^
and other assistants.
Method 9f securing the Bedms oftShips^ without wooden Knees made
jnade of one Piece, By Mr. Gkorge Williams. Trans. Soci^
eti/ ofartsy tot. XXVI I ^
In this method which Mr. Williams proposes for securing the
beams of ships, triangular braces of wrought iron are to be screwed
to the upper side of the beamj and also to the sh^.p's side. These
braces resea^ble the Roman capital A, and are let into the beam,
and firmly fixed by three bolts ; one near the angular point, and
two others in the cross part. The ends of these braces are. turned
up, and b()lted to the tirabcis of the ship's side, by two bolts
passing through each end and through the timbers and outside
planks, which secures the beams from lateral motion. In order to
secure the beams in a vertical direction, a block is fitted under
each, and mortised both into the beam and the side of the ship.
Two iron straps are bolted on each blt>ck ; one end of each of
these straps is fixed to the deck b.eams by the same bolts as the
upper brace: the other ends are bolted against the inside planking;
and an oblique bolt goes through the middle of each strap, the
block, and the ship's side.
*' In this method less iron in weight, and fewer bolts ar^ neces-
sary than in the iron knees before in use : there is also less strain
upon the bolts : In my method much more room is gained be-
tween decks for stowage and working the guns, and even a port
hole may be made under the beam." Mr. W. also gives the fol-
lowing calculation relative to the saving that will be effected by
this method in a 7^ gun ship, or East India man, viz.
Ions. Cut. Qrs. lb. j£. s. d.
Copper bolts 2 1 3 9 at U. 4{f. per lb. 305 8 0'
Iron 2- 12 0 0 Q.i bids, ptr cut. 145 12 O
Three men and one boy's time for a month ^5 \7 6
Timber ^ - ..- - -50 00
I. 546 17 6
Observations. — The difficulty of procuring a sufficient number of
wooden knees of a natural form, has long been felt and acknow-
ledged, and has induced several ingenious mechanics to devise me-
thods of either diminishing their number br superseding their use
altogeiher. Of the inventions for these purposes, we have givert
a summary at page 368, of our fifth volume. In the mode propo-
sed by Mr. Williams, we regard the block inserted beneath the
end of the beam is of considerable utility in preventing vertical mo-
Cqpiain BoltotCs^ Naval Iwpravemfntr. 3!>
lion: and if Mr. W. be correct in bis calculation relative to the
saving which will be effected by his method, he deserves a distin-
guished rank in the list referred to above. The society bestowed
their silver inedal on Mr. VV, for bis invention.
Naval Improvements. By Captain William Bolton. Trans^
Society of Arts, vol. XXVII.
Some doubts having arisen relative to the practicability of rig-
ging thejury masts, invented by Captain Bolton, and noticed al
page 309 ^>i our fourth volume^ he has transmitted to the Society
of Arts, d model completely rigged, in order to remove these
doubts. From this it appears, in tonsequence of the angle being
more obtuse, that the rigging so placed will give gi eater security,
supersede the necessity of cathers pinning, and suffer the lower
yards to be braced sharper up.
Another of these improvements is a mode of striking the top
mast, which Captain Bolton has effected by the mahtier in which
he has fitted the top-mast rigging, " whicb admits of it being set
Up, almost instantaneously, at any point the mast shall descend
to; the advantages of which are many^ more particularly when the
ships are riding hard in open roadsteds.*
Captain B. has also presented to the Society a model, illuBtra^
tive of a plan for fitting up a ship's lower rigging, which is capa.
ble of being effected by one man. This improvenient "consists
simply of ascrew attached to each shroud, and tightened by a nut
under thie channels, which should be well secured by iron clamps,
or knees for that purpose ; the expense will be far less than in the
common mode."
Captain Bolton also requests that the passage which we have
quoted in the article above referred to, after the full stop at main top,
be expunged, and the followir^g one be substituted in its stead.
^'The square fore top mast passes through a cap made from strong
plank, into the square holes of which the heads of the two tempo-
rary masts above mentioned are inserted, and the heel of the top
mast is fidded on the treble trees, or top, as in common, and the
mast rigged as usually. The object of the strengthening cap it
to steady the spars, and also serves to fid the top mast on, if
thought necessary."
Obsercatiom. — Our readers will easily recollect our sentiments
on naval inprovem^ts in general, and as readily perceive their
importance to a nation like this, wliich reigns the undoubted queen
of the ocean, and whose flags are constantly displayed in every
quarter of the world. We considered Captain Bolton's former
communication relative to jury masts as worthy of being attended
NO. 23. — VOL. VI. r
34 Captain Bolton*s Naval Improvemenis.
to by naval men, and he has not rendered it less so, by this addi-*
tional information. This method of rigging ships in general, and
bf securing the shrouds, seems to possess some advantages over the
common modes, and is at least entitled to the ccuisideraiion of per-
sons concerned iu adairs of this naXuro: and we trust, in whatever,
relates to this momentons branch of national economy, that cus-
tom will yield to ieason, and prejudice give way to ntilty.
Method of constructing commodious Houses which earthen Walls. By
Mr. Robert Salmon. Trans, Society of jlrts^ voL XXVII,
Th£ moulds made use of by Mr. Salmon in this kind of building
fpr the purposeof ramming the earth in, consists of two planks abou^
twelve feet long, twenty inches broad, and one inch thick ; such
being made in two breadths, and strengthened by several, cross
pieces. Holes are' made through the top and bottom of tbesc
pieces and the planks, to Receive iron bolts, which hold -the boards
■ parallel to each other, and at a proper distance for the thickness
of the wall; which should be about fourteen or sixteen inches. — -'
These bolts have a large head at one end, and key passing through
the other, by" which th6 distance of the pianks from each other
is preserved. The foundation^ of the wall is to be laid with brick
or stone, and carried about nine inches or afoot above the ground.'
The planks are then placed upon this wall and bolted together^
having pieces of board put in for ends of the mo»ld : these are
placed betwecii parallel b6lts, passing through the side planks for
the purpose. The m<juld being thus ^properly placed upon the
wall, it is to be filled with earth, and properly .rammed down ;
after which the bolts are to be taken out, the platiks removed and
put together again upon another length of the wall,- and thearam-
med with earth as before. But in this case only, one of the end
boards is necessary, the bolt at the other end passing through
the holes in the end of the wall which were occupied by the end-
bolts in the former leilgth. In this manner straight walls may be
carried on to any length, and when one course is finished, the
mould is to be placed upon that course, and another completed^
and so on to any height required ; always inserting the lower bolts,-
of the frame through the holes that were made by the upper bolts
in the preceding cpurse, in order to insure the upper course being^
pUiced directly above the former. When the wall is required to*
be thinner than usual, blocks of wood may he placed under the
bolt heads, to diminish the distance between the planks to the pro-
per thickness the wall is intended to be.
When the angles of buildings are to be formed, four of these
planks are put together to form a right-angled mould. For this
purpose, one end of each Qf the inside planks is furnished wit^ .two'
Afr. SdtnofCs Mtthodof constructing Walls of Earth, 35
eye-bolts, through which ^holt being passed, forms a kind of hinge,
and connects the two moulds together ; and these are kept at
right angles to each other by means of an iron rod hooked into
eye-bolls fixed in .the planks at some distance from the angle. The
outside planks are 6xed together diii'erently. One of them is made
larger than the other, and this has holes near its end to receive
bolts fastened to the pnd of the shorter plank, which are secured
on the outside of the longer b}^ k^ys, as usual. ** In building the
angle wall, it is necessary thja(t the vertical joints formed between
each mould should not be over one apother, but arranged in the
same mannei- as in brick work ; this is accom4')lish<Ki by making
the lower course of wall upon the brick work only half the length
of the mould, which is done by pfecing the end board of the mould
in the middle of it. The next course over this is to be made the
whole length ofthe mould, the next only half, ^nd soon.'*
After thus describing the moulds and their general application*
the following particulars necessary to be attended to in the pro-
cess appear to be too essential to be omitted, and are therefore,
transcribed from Afr. S.'s. account of his experience. " Having
carried oiie course round the building, it frequently hapfiens that
the top thereof becomes too dry to attach to the next course ; and
therefore it is adviseable that as soon as the frame is set for th«
succeeding course, a small quantity of thick grout, composed of
2-5th lime, and 4-6 ths earth, be poured on the topof each course, im-
mediately before the first layer of earth be put in. A very small quan-
tity is sufficient, and will add much , to the strength ofthe work,
by cementing the courses well together at the joints. The work-
man should also, with the corner ot his rammer, in ramming
home to the upright joints, cut down a little of that part of the
wall, up to which he works ; thii will mak« the upright joints
kty together, and unite in a solid manner. Having thus proceeded
and got up the walls, the next thing will be to stop the bolt holes, with
^prtar, made of l-4ith lime, and 3-4ths earth, the same jas the wall.
*' The earth proper for this work should be neither ^and nor
clay, but partaking of both. Clay is particularly objecuonable,
as is also chalk, or calcareous earth of any sort. Sand is also not
proper, unless accompanied with some binding quahty : the bold-
er and coarser the sortof earth, the better. When used, it should
retain no more, moisture than just to make it adhere together, un*
der thepressure ofthe thumb a!nd finger. Notwithstanding earths
bordering on sand appear to make the strongest work, neverthe-
less good earths may oftei^be found in parts that do not abound
with sand. Those that abound with a mixture of grit or fine
gravel are generally the best. Havipg provided proper earth, as
much should be- put in each layer as to form about an inch and a
half when compressed by ramming.
*^Thie rammer should not be more than half an inch wide on the
36 Mr. SalmorCs Method of constructing Walk of Earth.
edge, in order that it may more forcibly compress every part of
the earth, which a flat rammer would not do so well.
'* In making walls, about three inches in thickness of loose
earth should be put in each course ; which done, the same, by
means of a trowel made for the purpose, is drawn back and clear-
ed from the face of the wall, and the space then filled up with the
facing composition, forming upon an aver^-ge about one inch in
thickness ; the whole then is firmly rammed (in which, and proper-
ly preparing the facing stuff, much depends the perfection of the
work,) till It is quite hard, when it will be compressed to about
one inch and a half in thickness, rhe common tacing stuff is com-
posed of lime one part, and earth, the same sort as used for walling,
three parts. The lime and earth mixed ancj slacked together, the
same as for mortar. The more it is slacked and wetted, the bet-
ter, provided time c^n be allowed for it to dry and pulvei^iije eo Ha
to be fit for ramming. The better sort of facing stuff may have
a small quantity more lime in it," •
Mr. S. then offers some further directicms relative to making
the foundation of brick or stone ; the proper season for performing
the work, which is any time when the earth can be procured in
a state ai sufficient dryness for ramming ; and the method of
forming the spaces for doors, windt)ws, &c. which is to be done
either by fixing the cross boards of the moulds at the required
places, or have rough c^es made purposely the size of the win-
dow, &c. With respect to finishing, he observes that the walls
of common, cottages may be washed over with lime and sharp
sand, which should be made up in small quantities, and used while
hot. ** For better kind of cottages the better sort of facing stuff,
and tbenjj as before, the whole lime^whited. Qr if i( be required
to make the finishing, as perfect as possible, the following is the
best mode, viz. with water and a brush thoroughly wet, and soak
the face of the wall for tvvo or three yards in superficie at a time ;
all which part, during the said wetting, should be continually nib-
bed an4 worked about with a han^ flout, till such time as the sur-
face is rubbed smooth and even, by which the facing composition
will work up as to become a pleasant regular colour, the face smooth
and hard when dry, and not liable to scale off as a coat of plaster-
ing would do. The finishing will be still improved by a small
quantity of Hme being put into the water used for snaking the face,
and if after the wall is. well soaked and rubbed, as above mentioned;
there be thrown thereon some of the lime and sand, (such as used
for lime-whiting) and that also worked into the face ; the face will
then become as perfect and hard as stucco.'*
" With regard to the expense of wails of this sort, as labour is
the principal part of the expense, and as in some placed lal>our is
dearer than in others, the best mode of estimating at di^erent
places will be from the quantity that a man should do in a day,
Mr, Salmon's method of constructing Wdh of Earth* 37
and which I have found to be 1| yard superficial, in thecommo^i
day's labour of ten hours.
" At this place (Woburn) the expense maj^ be estimated as fol-
lows:
Labour to makins; facing composition, fitting in and £ s. </•
ramming 10 a 1<) inch wall, where the earth is at hand
(labourers being 1*. IQi per day) per yard superfi-
cial . . . . - . --02C
Value of lime used in the composition rammed into
the face of a yard superficial (lime being Hd. per bush-
el)-". O
Lime and labour to i ubbing up and finishing the out-
side face of the wall - - ... - 0
Total finished and faced on one side. - - 0
If a wall to s| garden or other\yis«, and finished and
and faced on both sides, then add • «. - O 0 S
0 3
O 3
2 a
Total for walls finished on both sides.
P 3 4
Otservations. — This mode of building strong and durable houses,
with no other materials th<m earth, has been practised forages In
the pr 'vince of Lyons, in France. This art, though at present con-
fined almost exclusively to the Lyonese in France, appears from
a passage in Pliny's Natural FJistory, to have been known and
practised at a very early period of antiquity. M. Goiffin pub-
lished a treatise on thia kind of building, termed Pist\ in 177?,
in which he gives it as his opinion, that the art was practised by
the Romans, and by them introduced into Frante. The abb6
Rozier also says, that he had found traces of it in Catalonia ; so
that Spain, as well as France, contains a single province in which
this ancient manner of building has- been preserved. The cheap-
ness of materials, and other advantages attendii;i[g this art, when
properly executed, however, render it worthy of being introduced
into more general use, particularly in those situations where car-
riage is difficult. or impracticable; and for msiny farm buildings
•which require to be of considerable extent, and are therefore pro^
portionably expensive. Houses thus built will last a great length
of time ; for M. Francois Coinlei-aux, who composed a work oa
this subject, says he had pulled down some of them, which ap-
peared from the title deeds in the hands of the owners, to be more
than a century old. MAst of the country houses of the rich
tra4ers and manufacturers of Lyons are of this kind, covered oh
the outside with painting in fresco. But as paintiiig of this sort
is little known or practised in this country, we would recommend
ifaat instead of it, the walls, if not finished after Mr. Salmon's
38 • Mr. Salmon's Mdkod of constructing Walls of Earth*
inethod, be plastered and handsomely pebbled, which would give
the buildings a more rural and neat appearance : or. when this i^
not so much an object, we would sugiiest as a more expeditious,
and consequently « les? expensive mode of pebbling, that the peb-
bles be regularly mixed with the outside fac ing stuff*, and this
used iu a rather larger proportion. The plnstering and rough
casting or dashing, should not be executed for five or six months
after the walls« are built, or until th^y are perfectly dry ; and to
prepare them for plMStering they should be closely indented with
the point of a hammer or other proper instrument. ^
The poor in many parts of this kingdom, and even in this
(country, suffer greatly from the inclemencies of the weather, owing
to the ^wretchedness of the hovels which they inhi^bit ; the mode
of building cott^es is so expensive, and, in many places the dif-
ficulty of procuring the usual materials for that purpose so great,
than an improvement on this subject is of great in^poitance, and
Reserves the encouragement of the public. Most of the attempts
at building in pise which have, at different times, been mad(! iu
this country, have been unsuccessftil, either through want of dis-
crimination in the choice of materials, or of skill in the execution
of the work. Mr. Salmon, however, has not only completely and
practically overcome the difficulties attending this mode of con,,
structing comfortable habitations, but has also much improved
the machinery necessary in thi^ mode of building ; and as his
essay on this subject is the result of experience ^nd success, it
deserves to be taken as a guide by those who wish to put this
method in execution ; and we should be extremely glad if any ob-
servations of ours be instrumental in facilitating that object.
As Mr. S. has not said much relative to the earths pr(»per for
being used in this modt of building, we shall add a few remarks
on this head.
All earths may in general be used that do not possess the lights
ness of poor lands, nor the stiffness of clay ; earths fit for vege-
tation ; brick earths ; and strong earths, with a n[iix(ure pfsmall
gravel, which on that account are improper for nv|king either
bricks, tiles, or pottery, bu| maEe the best pist*. The following
appearances indicate tha( th^ earth i(i which they are found 19
fit for a building. When a picliaxe, spade, or plough brings up
large luflips of earth at a time; when arable land lies in clods o^"
lumps ; when field mice have made themselves subterranecHis
passages in the earth ; all these are favourable sign^« When the
roads are lower than the adjacent parts, and the sides support
themselves almost upright, it is a sure sign that buildings of this
}und may be constructed iu that neighbourhood. Proper earth is.
found at the bottom of the slopes oi low lands that are cultivated,
as th# rain constantly \^ashes the go,od earth down to these
Mr. Salmons Method of constructing Walls ofEaM* Sy
/)Iaces : it is likewise found on the banks of rivers. Earths may
also be mixed in order to render them more ^t for this purpose.
Strong earths must be compounded with light; those in which
clay abounds with such as are chiefly composed of sand ; and
those that are rich with others of a poor nsiture. It will not be
amiss to mix with the earth some small pebbles, gravel, rubbish
of mortar, or any small mineral substances ; but none of the ani^
mal or vegetable kind must be admitted. Such haid substance*
bind the earth lifmly between them ; so that a well worked earth,
in which there is a mixture of gravel, becomes so hard at the
*nd of about two years, that it is nearly as difficult to cut as free-
»tone.
Experiment, however, in this case as well as in others, is the
Surest test; and this may easily be effected by taking a small
wooden tub or box without a bottom, and having dug a hole in
the ground, and placed a flat stone at the bottom, put in the tub
or box, and ram the earth dug out of the hole about the outjside
df it ; then ram the earth interided for the experiment, into the
tub, in the same manner as is to be practised in making the wall-
AVhen the tub is full, let it be taken out, and, being left a short
time to dry, the compressed earth will easily come out of its case.
The lump is then to be left till it is completely dry, and if it do
not crack but increase in fiardness, it is fit fot building. A variety
of earths, when they occur iii the same neighbourhood, as is somew
times the case, and also their mixtures, may be tried in this way,
and thafc whiph is most proper for the purpose chosen.
It has been stated thai a rammer accustomed to the work,
with the assistance of his labourer, is capable of raising four
Square yards or thirty-six Square feet of this kind of wall in one
4ay, which is considerably more than Mr. S's statement allows
to be effected in the same time. We however fully agree with Mr.
S. that the soundness and durability of the work depends in great
measure upon the perfection of the ramming ; and we conceive
that it is Indispensibly requisite that this operation be continued
for every layer of earth, till the impression of the ramming in-
strument be hardly perceptible. It may also be remarked that
the ramming would be considerably expedited by the use of two
rammers : one made of any sort of hard wood with^a face much
broader than that recommended by Mr. S. to be used till thc^arth
was tolerably compressed, and then the operation completed with
an ircin one of the kind mentioned above. Besides the advantage
of cheapness, this mode of buildmg possesses that of being suscep-
tible of execution by any common labourer, under the directioa
ef a judicious superintendant.
For the Indian method of constructing rural buildings of aimi^
hr materials, see our Snd volume, page 32, '
( *o )
On Iris seen in the Dcx, and a lunar Irisy with a?i A/mot at ion, Tt^
A. M. Phil. Journ. No. 1 IJ.
One morning, as the author of this communication was riding
across a meadow, he perceived on the grass, on that side of him
opposite to the sun, a beautiful straig^ht line of prismatic colours,
constituted by the refraction and reflection of the solar light by
the dew. The line extended from the observer across the mea-
dow, and formed an angle of 45**, with the show of a vertical
object.
A few weeks prior to this, the same gentleman saw, about nine
o'clock one frosty evening, a beautiful circle round the mooiK
which exhibited all the prismatic colours, whenever a fleecy cloud
kitervened between the observer and it.
Mr. Nicholson, in his 'annotation, remarks that, " the rainbow
on the groQnd was observed at the beginning of last century by
Mr. Langwith, Phil. Trans. No. 269; and Mr. B. Martin in his
Grammar, p. 213, correctly observes, that its figure will be a hy-^
perbola, parabola, or ellipse, according to the sun's height. A. M.
must have seen one of the legs of a ^urve of one of these de-
scriptions."
Observatioms^'-^^yt think with Mr. Nicholson, that his corres-
pondent must have been mistaken with rctpect to the. figure of
the iris which he saw in the dew, and conceived to be a str.iight
line ; as from the circumstances by which it was produced, it
must have been a part of a curve. This will appear evident if
we consider the rays of light as constituting a coue, having its
vertex at the centre of the sun ; and the horizontal plane on which
this iris was seen, as that by which the con^ of light was cut'
in forming it. When the centre of the sun was in tbe horizon,
the section made by the horizontal plane would coincide with the
axis of the cone, and the section evidently be a triangle. In this
case, however, no iris could be seen. As the elevation of the sun
increased, the coincidence, or parallelism of the cutting plane, and
the axis of the cone would be destroyed, and the section for some
time make a greater angle with the base than the side of the
cone ; during which period the iris would be a hyperbola. When the
elevation has attained that degree at which the horizontal plane
and the upper side of the cone of light are parallel U^ each other,
the figure of the section would be a parabola; which would im*
mediately be succeeded by that of an ellipse. Now as the parabo-
lic figure can only obtain at the moment that the side of the cone^
and the cutting plane were parallel, the probability is exceedingly
Mr. EUk <m the Propagation of Sound through mdastic Fluids. 41
great, tbat it was not this figure that was seen by Mr. A. M. ,
As this communication is dated Dec. 14ib, when the son does
not attain any considerable elevation in the early part of the day,
and it is observed that the phenomenon had been ** lately" ^een,
ther* can be little doubt that it constituted a part of ow of the
]e);s of an hyperbola, and not a sfraight line, as was supposed.
'1 hat this, however, wa» the particular curve cannot be c<»nchnJed
with certainty, as the precise time of the observation is not men-
tioned ; which we conceive at all timfes to be au. essential requi^
site in things of this nature.
a=ss
On the Propagtifion of Sound through uiielastic Fluid*,. By Fr aK«
CIS Ellis, £.v^. xvitk an Observation by Mr» Nicholson. Phil*
Joum. No. 1 13.
Mr. Ellis states that he was bathing in a warm bath atChel^
tenbani, and having immersed his head in the water, he was sur-
prised by a hoarse jtirring notse passing through both ears ; this
noise he supp»)ses to have resembled what would have been ex-
perienced it a sheet of tin had been placed over each ear, and
Btiuck simultaneously with small hammers. ^On examination,
he found that the water in the hath was heated by steam, con.
veyed into it by means of a metallic pipe, which entered the bath
at one of its angles ; and in which the condensation of the steam
produced at intervals, a dull clicking sound. I'Vhea only one ear
was immersed in the watery Mr. E. ascertained that it was ibi^
sound which he had previously heard, but altered mod augmented
by passing through the water of the bath from the tube to his
ear ; a distance of seven or eight feet. Me also remarks, that,
when his head was submerged, be had distinct, but simultaneous
sensations of the jarring sound in each eari.
Mr. Nicholson observes that this noise was of the same nature
as that of simmering ; and like that also was produced by the collap*
sion of the water rushing into the vacuum left by tb«^ bubbles of
steam. He thinks the different sensations which Mr. Ellis expe«
rienced arose ffom one of his ears being more favourably situ-
ated for receiving the impressions of the undulatery hiotiou by
which the sound was conveyed, and which would consequently
cause one of tbem to receive a stronger action than the other.
** If this were the case, the sensation ought to have been single,
when the face was directly opposed to the steam orifice."
Obserxati(ms. — That sound is capable of being propagated
through water, is a fact which has long been known; but difle.
rent opinions appear to be entertained respecting it. Mr. Ande.
ron^^in the Philosophical Transactions for 174S, states that sound
.Sua^.— VOL. VI. o
4$ Mf\ SpfincerU Anthrppo Tdegrap/i.
is transmitted but faintly tbraygb water, Mr. Hauksbee, in tbei
same work, relates an experiment wbich l^e made for tbe purpose
of aec^i tailing tbis point. He surrounded a gla^s receiver ctuH
taining a bell with water, and on causing the clapper to strike
the bell, be found that the sound bad lobt very little of its audi,
biliiy, Hy the introduction of ^be winter i(ito the vessel that con-
tained the receiver ; but it wsts much more mellpw, sweet* a-^
grave, apd ai least two notes deeper than it was before. Mr.
Kllis fopnd tbe *' dull clicking sound" of the tu|3e changed into a
^' harsh snapping noise,'' by passing through the water of the
bath for the space of seven or eight feet. It ought to be remarked,
however, that there is ^ considerable difference between Hauks-
bee's experiment and the circumstance related by Mr. Ellis : in
the former instance the soui^d was transmitted through both watep
and air, and the thickness of tbe aqueous stratum bore only a
small proportion to that of the aeriform medium ; in tbe latter,
the propagation was wholly through water. That t^is circum- ,
stance gave rise to a difference in ^he sound is evident, from thQ
different sensations experienced by Mr. £• when one of his ears
was immersed in the water of the bath, and the other remained
in the air*
i. Anthropo Telegraph, cr Mode of Commvnic^wn in the Day or
I^isht^ hi/ Disks. By 3/r. Knight Spencer. Transx Sodcfu
qf Arts, vol. XXm.
2» Homograph^ or Method of Cotnmunicafkm by Signals^ on Sea or
Land* By, Mr. James Spravt. Ibid.
1. Mr. Sp|:ncci^'^ porta.ble military telegraph censists of ^,
pair of disks made of basket work, ^bout \S inches diameter,
painted white \yith a black ball in the centre, weighing about oae
pound each, ^nd furnished with handles 6 inches in length. A&
this is the whole apparatus necessary for day signals, th^ expense
is very trifling. When they are used, the person denominated
the telegrapher holds one in each hi^nd, and represents the ten
numerical characters and other requisite signals by displaying
them in different po§itip|)s. When the signals are to be mada«
tbe telegrapher^ with a disk in each hapd, puts himself in the
position of attention, facing the corresponding station, and hold«>
ing ^he edges of the disks forward. The numbers l^ 2, 3, are
represented by stretching out the right arm, so as to make angles
of about 45**, 90®, and 135° respectively, with the body ; while
the left arm maintains its position close to the side. Ifae nume»
rals 4, 5, and 6, are denoted by stretching" the left arm in ^
similar manner, while the, j^igh^ remains still. To repregei^t
Mr, SprM^'s HwnQgrapL 4^
ft 8y and 9, both arms are stretched at the same tim^ so as to
make similar aogles ; and the cipher is signified by placing the
disks one behind the uther^ and htilding them over the head.
The period which is to be made at the close ol every number^ is
expressed by bringing ihe ditik in the right hand in front of the
breast, and placing that in thie left on the back at the same time^
in order that it may be seen both ways from the middle stations*
The signal of communication i« made by the telcgrapbeF.facmg to
the right, and displaying one of his disks over tbe other : and that
of error by a union of the positions denoting 1 and 6*.
As a proof of its simplicity and the ease with which a perfect
knowledge of it may be gained, Mr. Spencer observes^ that he
engaged indiscriminately four privates in the South Glouce&ler
Militia to assist him in making expernnents, and after one hour's
drill, they made every signal with the utmost correctness. He
also adds» " my signals, like those used in the Royal Navy, are
numerical, and of course without limit as to the extent to which
they may be carried, and with the assistance of Sir Home Pop*
ham's numbered Dictionary, now generally adopted, every kind
of communication may be made, and conversations on any sub*
ject cariied pu at a distance from one mile to three or more,
according to the circumstance of situation^ weather, &c. with the
utmost certainty. and telentyi"
When the signals are to be mad^ at night, a lantern, glazed
with green stained glass, and furnished with a reflector about
five inches in diameter, is fixed to the breast of the telegrapher,
and a smaller one glazed with common glass, is attached to the
c^htre of each disk, so that it may hang freely iii all pbsitions of
the disk required by tbe signals.
i. The simple contrivance which Mr. Spratt has denominated
ft Homograph consists iA holding a white handkerchief in diiier-
ent positions \vith respect to the body of the person who holds it ;
and these positions repn^sent tbe nine digits, with other signals
in communicatihg by a numleral intercourse. The number 1 is
denoted .by holding the handkerchief from the right foot to the
right hand, the arm making an angle of abctut 45^ with the body ;
5} from the right shoulder to the right hand in the same position ;
3 whan hbrizontally ; and 4 when further elevated. To denote
& it is held horizontally above the head ; and 6, 7 9 8, and 9
foNow in the reverse order to 1,2, 3, and 4 ; while 0 is expres-
sed by holding the handkerchief horizontally in front. For re-
pl«9i^nting 1, 5, 9, and 0» the handkerchief should be held, by the
diagonal corners, as generally prepared for wearing round the
neck* Bvt for denoting 2, 3) 4, 6, 7> and. 8, the opposite sides of
the handkerchief should be gathered in each baud, and the near*
tst extremity of it held to the point of the shouldec The other
positions are these: the signal of attention, in which tht handker-
44 Mr, IVhite's File for Receipts and l^^tters*
chief should be h^ld by two adjacent cornert and displayed <M
the right side ; the signal of repeat is performed by holding it iu
front, folded diagonal wise, with the left hand raised, and the
right depressed. When the hand;kerchief is fdded about the
right arm and stretched hori^tontally, it expresses an affirmative;
about the left, a negative : when the right arm is depressed, it
denotes an interrogative^ and the left iu the same position, signi-
fies annub
Observations. — Each of these methods of maintaining a' com*
toonteation by means of signals is extremely simple ; bat as only
doe figure ^an be expressed at once, the operation will necessarily
be much more tedious than when any number can be denoted by
a single signal, as Major le Hardy's telegraph, described at page
334 of our 5th volume. Both these, however, possess the advau^
tages of j3ortability and cheapness, and will be found to. answer
Tery well on a great variety of occasions where the other is in-
applicablfi The latter of these modes is evidently the most
Simple, and cati be had it! constant readiness iu all places ; but
the former is more extensive in it» application, as it may be used
ht night as well as during the day, which the other cannot*
£a€b is accompanied by certificates bearing testimony to its
efficacy and to the real inventor i and each was rewarded witb
the^Silver Medal of the Society.
■"gg^g— ■ ' ' ■ ' f 'V i ' ■ ■ J" fi ■ " ■" ■■ ^ ■ "■ "^^
Improved File fpr Receipts and Letters* By Richard WHiyD,
Esq. Trans. Society of Arts^ voL XXV I h
This invention consists of a metal tube with a c'onvex circular
plate soldered to the lower end of it^ for the purpose, of prevept^
ing. the papers from slipping eflf the file. This plate has a piece
o/ m^tal fixed to the under side of it^ containing a screwed hole
to receive the end of the wire which passes, through the tube : the
other end of the wire is* formed into a hookv and made sharp at
the point to receive the papers as. usual. When any paper is
required to be- taken off, those above it are. to be slipped up the
wire above the top of the tube ; the wire is then to be unscrewed
and taken out with the papers on it, leaving that wantad the up*
]2ennt)8t of those on t^e tube, which, renders it easy to be takea
away at pl.easure^ The wire with the other papers is then to be
returned to its place« and screwed: f«st, as beibre^ The U^\ •!
the tube should be made conical, and, its edges sharp, \0
pass mor« easily through the papers which are- to be: put on t<> f
iu
CbsnvatiQns*^^^\try persoa who has made use of a comrno*
jt#r. 6€irl09^t_ikmon4imti<m of the Coteiian T^ortii^. 4A
fiaper dh^ has felt the inconveniences which this invention of
Mr. AVhite is intended to remove ; and as it appears effectual for
the purpose^ we conceive, that there are few persons much con-
cerned in filing papers, who will hesitate in adopting hi^simpk
contrivance^ for which the Society voted Mr^ W. their W#c
Medal.
r ■ ^
5e
thmonsiration of tie Cbte&lati Theorem* Hy Mr: P. Barlow,
Phil. Journ. Noi IO9.
As this curiocis asd elegant property of the circle has ei^gagf d
the attention of many celebiated mathematicians, without being
acconi))anied with that success which -has attended many of their
oth^r pursuits, we shall present oUr msthcmatical readers witb
such Bn abstract of this demonstration as may just be sufficient
to enable them to perceive Mr. B/s method. Mr. Barlow com*
mences his demonstration With the wellkiiown trigonometrical
property, that if
Cos. X r^ p
Cos. 2x ri ^p* — 1
Cos. 3x re 4p* — $p
Cos. 4x =: Sp* r- »p* + 1
Cos. 5x 2: I6y — 120|^ + 5p
< it^. &c.
^ 1
Theii by making 2p tae y + *, imd mtihipfying each of tht
y
mbove fonmaim by twis there letulti
1 1
2 COS. X ^ y 4 ^ S C4>8. 4x :=: y*. + -■
d cos.JbB » / + -r fl cot. 5r ia y* + ~
i
OrgBiiertiHy • • « co«. mx =! ^* + —
. ym
' But mf. the getieral form is only deduced from odsc* ving the*
laiw of the preceding forms,. Mr. J^Krlow endeavours to obtain it
hi a- more diMttv manner, bf tmniposing and substituting in tbt
foUowing^ generai formula ;
Cos. tix tt S cois* X. ct)rf. (n— '1) jt^— eos. (n-*--2) x^
saA d^Mii^ thit he* infers tb«ii' ^ ttia^r conclude with certainty^
46 Mr. BdrloTv's Dcmdnstration pf the Cdterian. TM^rdh:
1
2 COS. X z= y +
y
that 2 cos mx = Y°* + —
ym
Prom these the two following equations are easily deduced ;
viz.
y' -*- 2y cos. X + 1 == 0,
and >•*■ --.2 y™ cos. mx -f 1 = X)
Then by substituting qy for y, ^nd the respective values fornned
in the above forms for 2 cos. x, abd 2 cos. mx ;^ proceeding^ccor.
ding to the natdre of eqiratioDs,.and the theory of divisors ; and
niaking use of r to denote the radius of the circle, Mr. B. obtains^
as bis results, the folloAvihg foriiiiilae and diviscrrs, viz,
C ^* y* — 2 qy r cos. Ox + 1
Formula (q^ y« — r"'), end divisors ^ "1* ^'""^ ^^ I ^^*- ^"^ + J
^^ J ^^ I q« y« — 2 qy i cos. 4x -f 1
> &c. &-C.
!' 9* y* -^ 2 qy r cos. X + 1
\qy^^(^ TCOS.3X + i
I q' y* — 4 qy r cos.- 5x + 1
&c. &c.
Then by substitution, and Euclid 13^, ^ the8<,are easily showtt
to be correspondent to the theorem itself.
Observations.'^ At the beginning of the article. Mr, Barlow ob-
serves, that it was by following the hints given by Lagrange|#i
hb *^ Thione des Fmctions j^milj^iquc,'' relative to Ike probable
circumstances which led Mr. Cotes to this discovery, that he
arrived at the present demonstration. Notwithstanding the .
weight which the opinion of Lagrange on this subject naturally
possesses, we are, however, incHued tor think it equally probable
that Cotes discovered the truth of this theorem by some tentative
method, rather than.conducted-'to it by* any Mgiilar pr#c«ss. He
would easily perceive that it was truc.for squares and tubes, and it
'is not unlikely tl^at he tried it for one..oc;two oil the higher powers,
and finding it answer for these also, he. thence inferred its generali-
ty. This, however, we offer not as a fact, but as a conjecture.
1
With respect to the general equation mx = y" + — , we
said that Mr. B. had endeavoured to prove it direetly ; and this
we did because we think it was only an endeavour; as it certainly
is not coBsistent wiih mathematical accuracy to regard any
thing as legitimately proved when the thing itsetf- caters into the
proof. We do no^ urge this as doul^ti^g -tl)e trutt pf wibut Mr^
S, has inferred ; as we think the law of the exponents of the .
Pr. Pearsofi's PropMalfor ohtmning an tqual Ttm^raturc. 4?
leading forms is sufficiently obvious and certain to warrant tlie
conclusion, and to have superseded the necessity of an attempt
to prove the general equation, above quoted, in a piore direct
manner. Upon* the whole, this demons traiion has afforded us
jnore satisfaction than any other we had previously read on tlie
the subject. But as it is one in which only a few of our readers
will feel interested, we shall not extend our remarks, but refer
such of them as are, to the following works, where they may ob.
tain much information relative to the elegant theorem and its
applications. Demoivre*s Paper, in the Philosophical Transac*
tions for 1722; Dr. Pemberton's Jipist. dc Cotesii Inventis ;'Dr.
Smith's Theoremata Lagometrica and Trigonome erica, prefixed
to Mr. Cotes*s liarmonia Mpusurarum ; Demoivre's Miscellanea
Analytica ; Warrng's Letter to Dr. Powell ; Sinipdon^ Essays \
and Lagrange's work, above mentioned*
■■■I I ■■' — ■■ Mil ■ _ II ^ I M.Hy I II I ■ .1 I Mill I
!• Proposal for an Institution for ohtaimng an equal Tcmp^iaturt is
Houses. Btf p.r, 'rk^\iiso:i, Piiil. Mag. Nq. 140,
C. On Dr. Pea kson's proposai Jjtr ehtaining an equal Temperature U
Houses, Bi/CB.sv.Vii.PkiLMa^.No.1^}.
1. At the con^menpement of t)iis article, Dr. Pearson refers to
a paper on the same subject, written by him and publiitbec) ill th^
IS^th No. of the Philosophical Magazine. In the paper herere*
ferred to» after enunoer^ting serine of the partial methods that have
been adopted for this purpose. Dr. P. observes : " All that is fur-
ther requisite is, to build a dwelling ho^ise of such 4 nature as to
unite the advantages of diffusing heat by the several modes of its
communication ; namely, oscillation, alteration of density ^f por-
tions of air with which it is in contact, and diffusion by elasticity
or attraction from panicle to particle of i^ir. The plan for such
a building must be devised by some ing^pious architect, qnder the
direction of a medical professional man competept{y informed oa
the subject of the philosophy which furnishes the principle." I{e
also offers'his assistance gratuitously both iu contriving and sup-
porting such an institution. . In the present instance, Dr. P. after
stating his assurance of the advantages which would result fro{u
such houses, from the success that has attended the rude contriv-
ances which have already been employed, mentions several re-
spectably names to whom he has communicated his ideas on the
subject. He then disclaims all merit of a new discovery, or even
' of a revival of an old one, and remarks ** I have much pleasure in
acquainting^ you at this time, that a few days ago an architect of
great celebrity, and to whom the British public owes many of its
naost useful works, «Qsured me that he would shortly produce %
n
4S Oil Mammg « miU md mitquahk T€m]ier<Lh4r€^
grand plan for axacuting my design for the purpoj>es of healthy
and conjoin a variety of cofDforti, and even some of the luxuries of
"(he hot cliiiiates."
. 2. The author of this comotuinication entertains sanguine hopea
of such a building as referred to by Dr. Pearson being speedily
erected in this country, and thinks highly of the advantages that
would re&dlt from it: butobserves, tliat it wirll detraict greatly frotn»
the satisfaction which such an institution would he capable of af*
fording, if it be confined exclusively to the use of the ricli. He
conceives that *^ the remedy of a mild and equable temperature
may be compassed by persons in the middle station of life, in their
own houses, aed at au expense not exceedmg what they would of
necef|ity expend in applications far less efhcacious. The tirst e»«.
sential seems to be merely a suite of two air-tight apartments and
an an ti- room opening into each other^ and having do other com?,
municationwith ther^&t of the house but through the anti-room."
These apartments ma^ eusily be made air*tigbt by double win-
dows, doors fitting close and listed, and being well plastered and pa-
pered, &c. For maintaining an equable teiuperature he thinks
^hat stoves of all kinds are inadequate, ^id tha]^ the mostxifectu-
al means would be by the use of sieam^
** All that is wanted is a plain and intelligible description of the^
mode of its application, which could be practised, by any ordinary
workman/' Some hints towards the accomplishment of this ob-*
ject are then suggested ; a^jt is remarked, *' tha.t the great source
of harm to persons of tender lungs, is the sudden apd great
changes of temperature, especially from coU ta heat ; which no
one who stirs 9ut in an English winter can well avoid," Tbis^^
however, may be eftected to a ceruio degree by holding a hand^
kerchief to the nos« and mouth, to p)*event the air from passing
into the lungs in its cold s^te ; but Mr. Ceneps thinks that this
mode canines the breath too much^ and that it might be better
accomplished by a kind of n^ask, consisting of a light frame fitting-
close to the lower part of th,Q face, and covered with three or four
thicknesses of gause. This would admit a sufficient qna^ntity of
air for respiration, without exposing the lungs to be si» fyr cooled
as to render it dangerous to enter a warm room or approach a
fire. In the use of such masks, he thinks there would be much
less to laugh at than there was in the first use of umbrellas, as a
roan's lungs are certainly better worth preserving than his coat*
Observations. -^The beneficial inliuence of a mild andeqnable tem-
perature, either as a palliative or a remedy for consumptivepatientt ^^
has been too long adnnttedand too frequently experienced to req^pre
any arguments to be used in its favour ; and the number of voy-
ages that are annually undertal^en to the south of Europe, by such
sut^rers, is a sufficient proof of the estimation in which it is hcH.
On counieractmg the Gasscsfimdin Coal Minek. '4lS
M this «dvaoUge however could be obtained in nearly an equil
ikgree by lutiiicial means at bome, much painful anxiety wouU
i)e avoided, and many comlbrts secured .which cannot be expected
ia a temporary resideace amongst foreigners. That the kao«ry
ledge of the present pcinod on the subject is adequate to the ertq-
tion of a building tbat sbaH afford those adva^tc^es in a high de*-
grefy cannot be doubted ; and we confess that we are sanguine
.enough to hope for its . completion at no very distant period df
t:Qie. We, however, are not without apiprehensjiome tliat it would
only be accessible to certain dasees, or iliat many would prefer a
lemporary confinement vt their own residesice, under somewhatt
less favorable circamfttaiDCJas. With auth, tii:.e bin^ts given by Mr.
ۥ on account of their simple praciicafcHlity^ deserve particular
/consideration. Steam appears to he the simplest and most ^fhe^ .
lual agent to he employed iii maintaining ain equable temperature.
Mr. C. considers enough as haying been, done to shew ite effectui-
I al application, and that all that is turn .wanted is the Se^t method
of using it on a ^mall scale for maintaining the air contained ip a
given space ^t the inquired temperature : and this we regard' as
an inquiry which is neither uninteresting to the philai^thropif)
nor unworthy of tlie philosopher,
I
— ... i .>.,.,!■.'■!■'.■ ' . ' 1. , '■■■ ..J ,,■■,„' I. ',.1 ,.,'<■ .'. I..LI II IJ iiJJL1>
I
On the means of cotaiteracting the Effects produced by the For/nfUigip;
of the Gasses found in CoaUntifies, FhU. JUag, Hfo. l^l^
The author of .this communicition observes, " In endeavour-
I ing to accomplish the important and desirable object before us,
we ought to addpt those measures which have a tendency to pre-
' vent the accun^ulation of noxious gasses ; for whenever they are
suffered to accuniiil ate, there is continual danger. I do* not know
of any vehicle, neither do I think it possible to devise one, at all
comparable to that with which nature has wisely provided us,
namely, atmospheric air." He th.en urges several objection^
against the use of chemical reagents for destroying the Jire»dafffp,
as well as against' other modes which have been proposed for
avoiding its effectis, and ihen describeii what he conceives tp
be a more praciicablM and effectual plan, viz. that of ven.tilst--
tion. ** V
The writer commences Ilis. directions with the first opening of
a mine ; as gasses of this kmd -are frequently met with in sinking
shafts, being evolved from fisettres in the strata. ** If two shafts
are sunk near together, ' thrilling Occasionally through from one
to the other is of great utility : hut in some instances this is by
no means sufficient to produce the desired effect. Should this be
the case, air^pipes of large diameter must be extended frpm ih0.
ISJO; $3»r— VOL. yi. H •- . i
5Q Ou €ounUr4ieiiMg theGoiut found in Coal Mtna.
. hHUitn of the sinking shaft, through tjbe.laftt ikriU into the adk
joiaiiig shafts in the bottom of which, provided it it not deeper
than the thrill last made, (in which case a scaffold will be naces-
sacyX a fire must be constantly kept burning : by this ineaas
pure air will descend the sinking shaft, carrying with it tke
extricated gfe^ses up the pipes into the adjoining* thqfiy whose
column of air will be rarified by the fire/- When a communica-
tion cannot be formed with another shaft, if wooden air-pipes of
about 15 inches diameter be put down the sinking shaft, and the
upper ends of them be made to enter the ash pit of the engine
boiler, properly constructed for the purpose, all the air required
for carrying on the combustion must necessarily be foroMl up
- tlie pipes, from the rarefaction which takes place in both the
ashpit and the engine chimney : hence a cireulation of fresh air
is kept up. Another method of effecting Ihe same purpose is by
means of blast cylinders, which are generally constructed to force
air down the chifiwey ; but this writer thinks the contrary way
is preferable.
The shaft being sunk, he pext describes sach meihods ofven^
tilation as are adapted to insure the woriiing of the mine with
safety. It is customary to begin with driving two parallel headi'
ings or levels near to each other, intersecting the separation by
thrillSf as often as is necessary ; always taking care tu stop up
the last but one in succession. One of these levels is denomi-
nated th^ oir-ipai^, the other the vMggonJway ; and both should
be made of a sufficient width and height so as to admit a good
supply of fresh air to carry ofi*the extricated gasses. In forming
them, the extent and number of air-ways, the area of the q^ipe,
and the quantity of gasses likely to be evolved, should al]l be tak?
en into the account. The sides of these should 'be made smooth
to prevent as much friction as possible, and to admit of -a
free passage for the air. They should also be made secure^ to
prevent the necessity of frequent repairs. The thrills should be
made as large as the air. ways ; and when they are made up,
great attention should be paid to their being airtight. ^' Doors
for the purpose of turning the airs should be well made, very
tight, and firmly fixed. Great care ought to be taken to pre-
serve the air-ways, &c. in good repair ; and should any part of
them give way, no time must be lost in securing them, and
removing the rubbish, that there be no obstruction to free venti-
lation."
Great care should be taken that no candles he iiitrutjed in.to
old cavities, as numerous accidents have happen,ed from this
cause ; and where there is any danger of fire-damp, the men
should never work naked. Should any unforeseen explosion take
place, those in immediate danger should throw themselves down,
cover themselves as we4 as they can, aqd proceed to that \^^%
^ On tounicracting the Gooes Jound in Coai Mines. 51
0
^i tbe mine^ whence the air is supplied as quicklyandas near
the ground as possible. When any one is so unfortunate as to
fall, either from the want of respirable air, or the choke-damp,
4;veiy exertion should be used to cause the air to circulate
through the place, that the snfTerer niay be brought out, and
tb« resuscitating means resorted to with all possible speed.
Ohservations, — It alWays gives us pleasure to record the judi-
cious observuittons of practical men on an important snbject;
from a conviction that this is the source whence the most inte-
resting information is to be obtained; and that a variety of r^
marks of this nature, if properly modified and arranged, would
form a code of regulations from which the happiest consequences
might reiiult. Perhaps no class of men among tbe labouring
rummuniiy are so ignorant and careless as miners, nor aiiy whoiti
situation and circumstance^ expose to dangers so imminent, or
T^tonsequences so fatal. Coufined to a narrow cell, surrdutided
with damps and darkness, with a mind unaccustomed to range
beyond the precincts of his iipmediaie object, tbe miner is natu-
rally wedded to tbe prejudices of habit, and disposed to resist, as
useless innovations, every theoretical caution for his safety. To
this cause, as well as to tbe inconvenience and expense attending
their adupta«n, it is to be ascribed, that artificial reagents hsm
been used either on 'So limited a scale, or with so little success,
ki counteracting the effects- of what miners eM fire-damp. But
wh^e this prejudice militates against the employment of artificial
means-, 4t ^ro>ws the peculiar necessity of using to the gceateat
<idv»ntage, those which nature has so abundantly placed within
^ur p3werc and it is in this point of view that we regard the re*
ftiiark^ i^ the present paper as highly valuable. They appear to
4>e th« results of considerable experience and observation, digested
by a mind accustomed toithink closely on the subject of its pttF*
suits. T^ moti^^ which /the writer assigns for their publi-
cation is also highly laudable ; viz. <' a desire of putting a sob-
jectof much impottanea in a train for investigation i' and' w«
sincerely hope that his example will be followed by other gentle*
men, whose experience has enabled them to contribute to the
> stock of practical information, ?o intimately comiected with tbe
ibining interests of this country^ and rtbe Avelfare of so great a
number of their fellow-subjects.
On the Method of transfomdng a Numbef from one Scale of
JSoiaiion to another^ and its' application to the Rule of Duodeci'
m(ds. By Mr. P£t£k Baklo^-— PAi/. Joum. No. 119.
Iif this paper, Mn Barlow first takes a comparative view of the
ifi Mr. Bartow on the Trathfptmaiiah of Numief*si '
Afferent scales of ooUlion. The division of uutnbers itfto petioii
<«f Itns, he observer, is of very ancient date ; but its use in otir pre^
wnt scale of notatiim is a comparatively late improvement, as is
-4rrideftt from the Urorks of the Greeks, who " employed twtntif^
seven, we may say thirty t^six^ different symbols, with which they
eould not for a long time express a number greater than 10,000 i
but they afterwards extended it to the square of this number." Th^
advantages of ihih notation consist in giving lo each digit a local as
veU as a simfrie value, and in their increasing in a ten fold pro-
fiortiOB. Mr. Barlow, however, thinks that either the radix 6 or
>1S would have better answered the purpose of no^tion, particu-
:larly the latter number ; but he does not conceive that even this
Itttter possesses a sufficient superiority over our present mode of
division to induce us to wish for a change, lie then proceeds to
fikt method of transforming a number from one scale to another,
irhich is to be effected in the following manner.
** Let r be the radix of any system ; and «, b, c, d, SfC. the
digits by which any number (N) is expressed in that system; then
we have N=: r"ii + r*-* 6 + ;*"*c -f t^'d, & + 9-
Thils 1746 in the decimal scale may be expressed by lO' 1 -f-
Id* 7 4* 10*'4 + 6, and in the duodenary scale, S467 may be re-
presented by 12**8 4- 12*'4 -f 1^*'6 + 7; and so on for others 5
twiiere it will readily be t)bserved that the number of characters
.iBcloding the O, in any s^ale of notation, will nevet exceed the
:nitthber that expresses the radix of the system/' After some re«-
i marks relative to the characters of the different systems, and his
:adoption-of ^ and 7 to represent 10, aiid 11, in the duodenary
.scale which requires two additional characters ; Mr. B. observes, if
fl^. be *^ the radix, and a, 6, c, d, and e, the digits in any other system
vChen in case of equalitv, we shall have j-^a + r"**A 4- »'"**c + r^*d
i^. CE rf^af H^ r^^ 1/ -f- )/»^«c^, ^-c; and therefore in con-
Htei^ting a number from one scale, to another, this equation must
-beCestablished," and solved. Notwithstanding the apparent un-
liniitedncsss'of this equation, it is of such a nature as'oniy to admit
^ofdn6possibl^ answer; and this wiU be best obtained ind^pen-
'diAitly of algebraie consideration, a^ in the following example.
. To trauiiforni the jromber 7 '^7 i , in the duodenary scale, into
the decimal notation.
* H^re 74671 = 1^7 + 1^*4 + l2*-6 + 12. 7 + 1
And 1^*7 = 145152
- -... ia'-4. :=, 6912 ,
12«'6 = 864
V^ .\ lt'7 . =x . 84
• '..*.-■ *. 1 ■. •.. :=',••!
!• »
Therefore 7467 1 =:, 153013
Mr. Soiiow OH the t^mrfomoH^n of Ifuufberf* \ 5$
From this example it will appear ibut d number may be easily
transformed from any other scale of notation into the decimal scal«
to which we are accustomed ; hot when the converse of this ki
required) the operation is more diihcuU, from our want of readioefig
in the management of the scale into which it is to be converteil.
For effecting this purpose, Mr, B< givtsthe following
Rule. ^' In thifi case the given number is always of the form
10"^ -f 10" '^6 + I0"'^c» 4-c, and the readiest wmy to transform
•it is, first to convert earb of the powers of 10, begitiAtng wtth the
lowest, into the required scale, then eaeh of the given terms in thf
formula into the same, the sum of which will be the answer.
When it is only necessary to observe that in mil the operations of
multiplication and addition, we must divide by the radix of tbo
system, setting down the overplus^ and carrying the quotient
instead of dividing by 10, as is done in common arithmetic.
Example, Let it be required to transform 1728 into the duode-
nary scale.
First 10 =2 ^ Also I7ad =: 10' -flO'7 + 1012X8
10*r: (^X^ = «4 8 = 8=8
TO' = 84 X <^ = 6V4 10-3 = ♦ X 2= 18
10*= e^i X 9 = 595* 10*-7 = 84 X 7= 4**
&c. lO'l =6y4 X 1= 6V4 .
th^efore 17^8 = 1000 Abs.
Several other examples are given to bivth this and the former
case, in order to apply what has been advanced to the multipli*
cation of feet, inches, and parts, &c. by similar denominations,
the following rule is given.
'^ Rule* Transform the numbers of feet, if above J 2, into the
duodenary scale, and set the inches, parts, &c, as decimals ; then
multiply as in common arithmetic, except, carrying for every 12,
instead of every 10, as in common operations.
Example, — Multiply 3 feet, 5 inches, 7 parts, by 3 feet 1 X
inches, 2 p^rts.
Here 3-67
3>2
3215
♦49
«i*Mii*«dMM
1 2-8542 = 12 feet,8^ 5^4f^ ^*** .•
O^jfn^AfioM.-^As the <jreek method of notation, to which Mr.
Bariow has just referred, is very little known in the country, and
the sources of iBf9][mation oni the subject are both scarce and dif*
*^ttlt of access, we shall endeavour to give a brief account of it in
54 Jdf' bariow <m the Trans/brmcUion oj Numbers.
this place. The superiority of our present system of arithmetic
over that of the ancient Greeks is so decided ^ to have long sinc^
entirely ^superseded the use of their methods ; t-nd the fragmeirts
of these which still remain upon record, are either scattered over
woiks which have not been translated, or contained in others, in
which the translators, on account of the simplicity, as well as ot
the familiarity bf the arabic characters to both themselves and
readers, have generally e^cpressed the equivalents to the Greek
operations in modern characters. Delambre (incorrectly printed
in Mr. Barlow's paper, Delambert) is the only person, within the
sphere of our knowledge, who has undertaken to collect these scat-
tered remains, and to compose a regular essay on the subject. This
is printed at' the end of the French translation of the works of
Archimedes, to which we owe the chief part of our acquaintance
with these ancient, and, in a comparative point of view, imper-
fect methods.
The notation of the Greeks, though much less simple than otirs,
%yas nevertheless very regular :
Instead of the characters 1, 2, 3, 4, 5, 6, 7, 8, 9,
they employed the lettiers *---«/?yif^ffld
Instead of making use of similar letters
for expressing the tens; they employed ««x f«y|or4^
For the hundreds they used f a r v f' x ^ ^ ^
And the thousands were denoted by a^y^e i K "^ ^
^ i i t I ^ i
From these examples of their method it appears that tbey had
recourse to the unit$ in order to express thousands^ with the only
difference of writing the iota underneath each letter* The con-
stant relation which subsisted among the four characters in
each of these vertical columns constitutes a geotnetlcal progres.
sion, the common ratio of which is 10.
Thus, for example a, », p, « or 1, 10, 100, 1000 ;
and ft X, a, 0 or 2, 20, 200, 2000 ;
and so on for the rest.
With these characters, they were able to express any number
less than 10,0000, or a myriad. Thus %i^B signified 9999^
^rvfi expressed 7582 ; and ix denoted 4,001. They also some.
times expressed a myriad, or 10,000, by putting a dash under the
*, which of itself denoted 10.
They also expressed any number ol myriads bj the letter M#
with the number placed above- it : <
thus * ^ y *
^^"' M M M M
denoted 10000 20000 30000 .40000 d-c'
and j^j signified S7 myriads or 370000, and to on for other num-
Mr, Barlougn the Transformation of Nitmhfirs. 55
Jj.ers.of tbe siime kind ; from which it is evident that th« letter ^/
placed beneath any number was ec[uivalent to what we effect by
prefixing lour cyphers to the right hand of the same number. This
is ihe not^iio^i employed by Euiorius, in his commentaries K)n
the works of Archlme^Qs; but it was ill adapted to the purposes of
.computation.
Diophantub and Pappus made use of the initials Af v placed after
tbe number to, express the same thing. Thus abAv,fi}lhi^ 7M9, &c.
implied 10000, SOOOO, 30000, ^c. respectively ; and ^rojSMv
,«4^ expressed 437^ myriads, 8097 units, or 43728097. This me-
thod resembles that which we employ to express numbers conv-
pounded of ditferent denominations ; as yards, feet, and iaches«
The same authors ali>o employed a still more simple method, thi^
was that of using a point instead of the initial Mv ; thus ^to0. ^^
jjenoted 43728pC)7, as before^ The Qreeks were thus enabled t^
express any number which did not exceed 9999. 9999^ whicti
they expressed by j9S4^. V^\A : a unit piorie would have made this
a myriad of myriads ; or according to pur systenii, 100,000,000
^ 10000^ or a hundred millions. This aujQl.)€r i.ii^n;iited the no-
tation of the Greeks, until Archimedes ^ippri^ed it to be taken for
a new unit ; and the numbers foun^ of tl^ese last, he called num-
bers of the second order. Jn this manner he expressed all tbe
numbers which in our systeip require X6' cyphers to express them.
Then taking for another jiew unit, the unit followed by iS
noughts, or the 4th power of the myriad, he composed numbers
of the third order. A uttit^followed by 24 noughts, or the sixth
power of the myriad, constitutied numbers of the 4th order. Ij^
general, l>y taking a unit followed by the 2nth power o.f.the my.
riad, he formed numbers of tha prder (n+ 1). fox example.; if \ye
suppose n r= 8, Snzr 16, a unit succeeded by I6 times 4 noughts,
or 04 noughts, will compose numbers of the ninth order, or (8 + 1),
,the whole comprising o5 figures. Hence, to express 64 figures,
Archin\edes required the 8th order of numbers. It is worthy of
xernark^ ,tl:^at this indefinite method of notation appears to have
l>een invented by hixp for a particular purpose, and to have been
used only once-: viz. for expressing the number of grains of sand
contained in a sphere, .the diatnetjer of wiiich was equal to the
distance between the earth and the fixed stars. Archimedes also
invented a method of expressing a geometrical series of which tbe
.first term was unity and the common ratio 10 : this he effected ,
thus A, ' ' 1^ p, fS *•» '•» &c.
I, 10, 100, 1000, K)000, 100600, &c.
Apollonius, , according to the relation of Pappus, made some
I convenient changes in this system of notation. Instead of tha
orders or divisions consisting of 8 cyphers, he supposed them to
be divided into periods of four, figures each. ^ The first period to
^^ ri^t hand was ^at of units ; the second that of simple myr
1^6 Mr. Bar low on the Transfurmctum ojf Numbers.
riads, the third was that of double myriads, or those of the second
order ; and so on. In general, the nth period of the number con-
tained myriads of the degree (n—l). Thus the same characters
occtirred in each period, but with a value always increasing, and
proportional to the successive powers of the myriad. The same
author likewise made some further improvements ; for an account
of which we must refer tbe curious reader to the third volume of
Wallis's work*.
The nought was not entirely unemployed by the Greeks ; but
H is only found in the works of Ptolemy ; where it is used to sup-
ply the place of a number in the sexagesimal notation, where no
value occurs^ TIjus, in the table of the declinations of the ecliptic^
0% ^y, i/^ signify D^ 24^ 16^^ and ^r^ (/, hi/^ denotes 6^, (/, 31^.
Among the Greeks, however, the zero was always used singly, and
liever combined with any other figure, as with us, to change its
value-
It only remains fot ua now to give a brief account of their me-
Ihod of expressing fractions. For this purpose, a dash placed to the
* right of a number, and towards the top, indicated that the nuipber
was the denominator of a fraction, the numerator of which was
unity. Thus /=| ; y=z l ; {^=1 ± ; ^u^zz ^. The fraction
1 had a particular character ; (, or <, or {f^ or K, When the nu-
merator was not a unit, the denominator was placed in the manner
of our exponents. Thus, »«{• or 15^ denoted -jj ; apd gp wa*
written {p The Greeks appear to have had no mode of ex-
pressing the parts of a unit in 9 similar manner to our decimal
fractions. For farther information on this curious subject we
must refer to Delambre's essay, and the works of WalUs, above
referred to.
. We shall now conclude this article with a few words respecting
Mr. Barlow's paper, This we consider as both ingenious and
novel ; but neither entirely free from errors nor pregnant with
utility. The former of these we shall endeavour to correct, as
well as to state in what we diflfer from the author relative to tbe
latter. In the first algebraical formula, the 9 appears to have
been an addition of the printer. In the first example ofduodeci*
nials, we think Mr. B.-wiil agiee with us, th^it the third productr
should be ^49 instead of y^9 ; that tbe suQi of tbe products should
be 1 1 . 7542, and not \% 8542 ; and consequently that the result
is 13 feet, 7^ 5^^ 4^^^ ^^^^f, instead of 13 feet, «^ 5^% 4f'\ ^^^'^^
as given' by him. This mistake has evidently originated with the
author. NVe do not agree with . Mr. Barlow that his method of
performing the multiplication of duodecimals \%akmyi preferable
to the commoii rule : for when the number ef feet does not exceed
1^, and not parts less than inches enter into eithtr faetm*, the usual
metbed evidently has the advantage. la -ether-^asee; and especi^
Oa the infiuaicc of Lighi on lie propagciian <f Saund. }^t
illy when a little custom may have rendered the use of th« two
additional characters and method of transferring the numbers from
the one scale to the other familiar, our opinion coincides with liis.
hqitiries cimcernmg the influence ^ lAght 6n the Propagation W"
Suund* By Mob£ST£ PXeolette.— 7o«r. de Physique^ «xj|;
LXVIIL
The subject which Mr. Parolette has chosen as the object of
ibis inquiry, is the relation which subsists betw«ed the action of
light and the vibrations of sonorous bodies ; and after some gene-
ral remarks on the importance of iight as an agent in natural phe-
nomena axkd its effects on other of our senses besides vision, be
states the means which first suggested this inquiry, to have been
the difference he observed in the sound of the wheels of carriages
before, and After day-breaiu The noise of the wheels appeared to
acquipe a more soaorous sharpness after the dissipation of tiarkik
iiess, and seemed to announce the friction of two substances posses-
sing a greater degree of elasticity than before ; and further obser^
vatioDS confirmed the opinion, that light exerted a considerable in-
fluence on the propagation of sound: The action of the wind
could not have much influence upon this propagation, even whea
moving in the same direction, as its velocity is less, and it ope»
rates only on large masses of the atmosphere. As the propaga..
tion of sound is affected by extremely small vibratii ns, Mr. Paro-
lette thinks it probable that this takes place in particles of a very
light elastic fluid of a peculiar nature, distinct from the gasses,
of which, aiccording to our present knowledge, the atmosphere it
supposed to consist,. He therefore endeavoured to contrive an in-
strument fur obtaining an accurate measure of the propagation of
tound, and determining whether his senses had been deceived.
As it is known tliat the vibrations of elastic fluids are alway ana^
logous to those of the particles of the sounding body, and that if
two strings, belonging to two instruments, be in unison, when the
One is touched the other will vibrate and emit a perceptible sound,
Mr. P. thought be could avail himself of these properties in the
coostruction of his appai^atus and determiDing the object of his
inquiry.
In forming tlie apparatus for this purpose^ Mr. Parolette took
two good violins, furnished with well chosen Naples strings, and
]iad the pegs made with copper screws, that he might be able to
regulate the tones with a greater degree of precision. He placed
tbeee violins on a horisontal plank, which was ten feet long and
^ight inches widei Having tuned thej»e,two instruments to the
Paris diapason, he fi^^ed a bit of paper to the second string of not
of tbem> for the purpose pi $ervin^ for a» index during tb4 course
310. 23.— VOL. VI. t
&S On the vffinence of Ugh t on the propagation of^ Sound,
of Ills experiments. As it was necessary that the distance between
the^e vio1in& should be suscrptible of vanation^ and also for
this to be marked with great accuracy on the plank that consti-
tuted the ba^e of this apparatus, one of them was fixed and the
other moveable. 7'hat to which the paper was attached was the
fixed one, and a line correspoodmg to this string was drawn on
the plank. The other was fixed upon a small wooden frame,
which was moveable on the plank by means of two grooves; and
stras drawn backwards and forwards by the application ef a screw
in the end of the plank upon which ihe instruments rested. The
frame contained an opening parallel to the second string of the
moveable violin, which admitted the change of place in the expe-
riments to be marked on the plauk. The apparatus being thus
constructed, the second string was pressed till it touched the third,
and then let go instantaneously. This fingering was done at the
same place, and in a uniform manner, and produced an oscillato>-
ry motion, which wsts heard on the corresponding string of the
other, viol in. The paper showed the vibration of the string at a
distance, and the violins were separated from each other until the
agitation of the paper ceased. This point was the limit of the
vibration, and was marked on the support of the apparatus, and
numbered 100. The distance between the two marks on the
plank answering to the two strings, was then divided into 100
equal parts, and each extreme division into tenths, that thefe
might be thousandth parts in the scale. The first experiment
was not only to furnish a standard of comparison for the iscale
of the apparatus, but also for the difference in the propagation of
sound, as determined in future experiments. This first experi.
m'^nt was made on the 14th of May 1803, and accpmpanied witU
the following meteorological observations ; vis. Fahrenheit's ther-
mometer 51*8% barometer 30*28 English inches, and tb€rh^gro.r
meter 39* '^^^ experiment was begun at 20 minutes past noon,
and repeated several times, and the apparatus always indicated the
same distance to a few thousandth parts. The whole extent of
this scale was 7 feet, and this distance was the limit of the
greatest propagation of sound under the influence of light in the
apparatus, which the inventor denominates a phonometer.
After this experiment, it occurred to the mind of Mr. P. that'
the effects of other causes might be confounded with those of
light, and that changes in the state of the atmosphere were most
likely to inftuepce the results of these experiments. He therefore re-
4>eated the experiment on three different days, and in very different
states of the atmosphere, and the greatest differeiice of th^ results
did not exceed three thousandth parts, which Mr. Parole tte thinks
ought rather to be attributed to the imperfection of the instru^
ment than to the different state of the atmosphere.
Mc P's next object wits to try his instrument in the dark, and
On ike Influence <^^ Ught on the propagation of Sound. 59
tjiis be ^id by tbe assistance of a watch lamp of a peculiar con-
struction, whicb afforded ligbt enough for observing the motion
of the paper, without lighting the room. Tbe following was the
state of tbe different instruments ; viz* Thermometer 53*24^, ba-
rometer 29*79> hygrometer 65, and phonometer 98*1 : the time
of observation was eleven at night, and the sky covered with
clouds. Several other comparative experiments were also made
both in the day and the night, and the results were constantly
favourable to, the influence of light. The mean term of the de.
grees of propagation of sound without light waH found to be 0*98 ;
and the mean difference of this propagation at noon and mid.
night was two degrees of the scale, answering t<» about \6 lines ;
when the experiments were made with the greatest caution in
guarding against any inaceuracy.
^ight has been considered to be more favourable than day to
the propagation of sound ; but Mr. P. concludes that this arises
merely from the absence of noise ; and thinks that the ear pos-
sesses more aptitude for hearing by day than by night, on account
of the stimulant action which light exerts on the nervous system ;
but this will not explain the phenomenon of the paper, which
depended upon the tremulous motion of the air in the room. He
then asks, is atmospheric air more dense in li^ht than in dark-
ness ? Is tliis greater density of the air, or of the elastic fluid
which is subservient to the propagation of sound, the effect of
aeriform substance preserved in this state througli the medium of
light ? This hypothesis, he conceives, would confirm Dr. Priest-
ley's opinion, that the propagation of sound in different gasses
was in the ratio of their densities. But Mr. Perolle, whose ex--
fieriments are inserted in the 3d volume of the Menioirs of the
Koyal Academy of Sciences ol Turin, has proved that the propa-
gation of sound depends upon the patur^ as well as the density of
th$ different gasses through which it passes. Of these oxygen is
best adapted to its transmission, it is certain, that during the
day, the atmosphere is more saturated with oxygen than in the.
night ; but it remains to be proved that this excess' is sufficient
to cause such a difference in the propagation of sound during the
two periods. Rather, may not light be the true cause of this
increased propagation ih oxygen and nitrous gasses ; as it is
known that the former has a great capacity for light, and the >
latter cannot be formed without its presence. As the velocity
,of light is 900,000 times greater than that of sound, it does not
appear unreasonable to attribute its effects on the vibrations
which proceed from sonorous bodies to the mechanical action
of its particles. Mr. Paroiette thinks that the more deeply nar
tural phenomena are investigated, the more cleariy we shall per*
ceive, that the powers by which the universe is moved reside in
ih« imperceptible particle& of bodies ; and that Uie granil^ results
So On the Qanera Lueicta.
df nature eonstitute only ao assemblage of actious, that take*
place* in its infinitely small parts.
OA#cn»tfft"o«5.— Whether we consider the nature or effects of
light, the number of phenomena which it exhibits, or the ad-
vantages which mankind derive from them, there is no object
more worthy the attention of the natural philosopher than this \
none which acts so considerable a part in the economy of nature^
The extreme divisibility of light, and the amazing rapidity of its
propagation, render any enquiries respecting it both delicate and
difficult ; and the smallest degree of success in researches of this
kind strikes the mind as the presage of important discoveries.
This communication, we understand, is to be regarded as an ac-
count of the first of a series of enquiries which Mr. Parolette btts '
undertaken to pursue. In a note, he observes, ** My object is
to ascertain the action of light in the various phenomena that
take place in the elastic finids by which we are surrounded.
This objject is connected with the mechanism of our sensations,
en the one hand, while on the other, it embraces the results of
those first combinations which escape our apprehensions.
The apparatus with which these experiments were made seems
lo have been well adapted to the purpose, and Mr. P. has at
least opened the way to an interesting field of inquiry ; and his
experiments are such as deserve to be repeated by other philoso-
pher8« cither with a similar apparatus or some other which their
ingenuity may devise as more proper for the pbrpose ; at the
same time we must profess that we entertain some doubt of the
validity of the inferences which he has drawn from them : it seems
eanier to suppose that he may have discovered a minute vibration
more readily in the day time than at night, than to attribute
llie whole effect to the immediate operation of light in the trans-
mission of sound.
Mil
1, On the Gamer ($ Lucida. B^. Mr. T. Sheldraks. fVitb
a Remark b^ W^ N.^PhiL Jourri. No. 105.
% On the Camera Lucida. By Mr. B. Bate.— PAt7. Joum.
Nv. 107.
3. On ik$ U$€ of ihe Cmmera Lucida at a subsiUutefor the
Camerm Obmsura. B;gf Mr. T. Shxldraks.— P^'/» Journ.
ifo. lU.
1. Ik this paper, Mr« Sheldrake institotes a kind of iw^irj
mpeptiUft tJ^e QomptreAiyQ meril? of tiie rtnera locida and
On ihe Omerm Lueida. ei
the camera obscura. The first of tbttc^ fa^ sc^rv^ represents
objects with more brilliancy and distinctness, and either singly or
in combination^ with perfect truth and correctness of perepective ;
\nii it places before the eye only a certain portion of the objects
to be imitated, and a certain portion of the paper on which the
imitation is to be drawn. The camera obscura fixes upon the
paper the whole p'icture at one view, so that the artist has only
to pass his pencil over it to render it permanent; but, under
some circumstances, tha objects are rather deficient in point of
brilliancy, and. somewhat distorted from the truth of perpective.
Mr. S. states, that he has found many inconveniences in using
the camera lueida, for which he could not find a remedy ; and
from the masterly drawings that have been made with the ca.
mera obscura, and the facility of execution obtained by it, he
thinks that it deserves the pieference. He concludes by observ*
ing : 'Mt appears then, that a perfect instrument to be used as a
(delineator is still a desideratum, and will be obtained when tlie
separate advantages of the camera obscura and the camera
lueida can be united in the same instrument, and not be dimi-
nished by any of the inconveniences to which each of theo^ is at
present subject.
Mr. Nicholson thinks that it certainly was the intention of
the inventor of the camera locida, '* that the tracing should be
made upon that part of the paper where the picture and the
point of the pencil can both be seen coincident, and ndt that
a copy should be t£^en in the manner described by Mr. Sbel*
drake/' This is to be effected by n>eans of the small stop which
regulates the quantities of light that enter the pupil of the eye
from both the paper and the prism ; and is easily obtained by a
little practice.
3. Mr. Bate conceives Mr. Sheldrake's statement to be too
unfavoorable to the camera liicida. He thinks that it possesses
some advantai^es not generally known ; and agrees with Mr^ N.
relative to the coincidence of the picture and tlie pencil ; but
thinks that the management of the eye in the use of this instru*^
ment has not been described with sufticienf minuteness. He then
shows Mr. Sheldrake's method of using the camera lueida to be
imperfect ; and describes his own, which has been attended with
better success. Mr. B. thinks the young artist may obtain art
essential benefit from a limited use of the camera lueida, by em-
ploying it to fix the outlines of one or two objects situated near
the middle of the view ; and that the accomplished, artist may
likewise save much time in the delineation of extensive and com*
plicated subjects, by using this instrument in determining as
inaiiy points as he deem important. The combined advantages
attending this instrunMnt, ** and al>ov^ all, the truth of the re-
.^ctcd image« under every eircamstance, give th|r camera lueida
6t Mr. On onjloating Bodies*
a decided superiority over all other known contrivances for the
same purpose."
3. Mr, Sheldrake's object in this second communication, is to
show that the camera lucida is not aa advantageous substitute for
the camera obscura. He, therefore, illdstrates the use of this lat-
ter instrument^ and then endeavours to bring the former one to the
same test. He states that the portability of the camera lucida,
which might be thought one of its chief advantages, is not so m
reality ; for it requires to be used upon a table or stand equal in
size to the camera obscura. The superior brilliancy of objects is
of no advantage, as this must be destroyed before the pencil with
which they are to be delineated can be seen. Jhe projection of
near objects is frequently a great obstacle lo the use of the camera
lucida, as '* it is indispensibly necessary that the light should fall
upon the pencil and the paper, or the view and the pencil wilPbe
seen so very imperfectly, that it will be almost impossible to make
any kind of sketch, however imperfect, with it." Mr, S. concludes'
his comparison with observing, that the camera lucida possesses
no advantage which will induce an artist who uses the camera ob*
scura, in the prattice of his profession, to abandon this latter la
order to adopt the former.
Obseroatiotts. — We noticed the specification of Dr. WoUaston s
patent for the camera lucida, at page 90 of our 3d volume, and
stated several reasons which induced us to give the preference to
the camera obscura, as well as noticed the want of (perspicuity
and precision in his description of the instrument and manner of
using it. The defect in this last particular induced both Mr. Shel-
'drake and us to conceive, that the object was to be seen upon one
part of the paper, while the drawing was to be made upon another.
This, however, seems to have been corrected by Mr. Nicholson
and Mr. Bate ; yet we think that some practice will always be
required before Dr. Wollaston's instrument can be employed with
facility.
Observations on loaded and unloaded Barges f Boats^ Beams^ or floats
ing Bodies descending wih Sti earns or Currents, and vihy the
heavier End will go foremost. JBy Geoege .OaR, JS«f. Fhil.
Mag. No. 141.
In this communication, Mr. Orr affirms that, when any body
floats in a fluid, there are always two powers opposed to each
other ; these are the specific gravity of the fluid, and that of the
floating body ; and that in proportion to the difference of these
will the bodies oppose each other. Another of Mr. O's propo-
sitions is, that ** when water is perfectly at rest^ it has found its
Mr, Orr onjlooting Bodies* 63
level, or all its particles gravitate towards the centre of the earth
in perpendicular and right lines." But on any change of state
taking place, the particles of. the daid are put in motion, by the
force of gravitation, and either endeavour to find their level again,
or continue to move down an inclined plane ; the bodies sus.
pended in this fluid partaking of the same motion. *' The velo-
city of a stream, river, or current, and of course of bodies that
float in them, will be greater or less, as the inclination^ of the
plane on which they descend departs more or less from the line
bounding the horizontal plane/'
The reason that heavy bodies floating with the tide make a
greater progress than the tide itself, is, that all the particles of
the floating body act in one mass ; and the less degree of friction
which takes place^ between a solid and a fluid, than between the
particles of the fluid. After some remarks on the collision of
heavier and lighter bodies, and the probable existence of an under
current from a bay when the wind blows strongly into it, Mr.
0. observes, '* All pressure on bodies floating with streams must,
whether the pressure be perpendicular or oblique, increase their
progress :— *if the pressure be perpendicular, it adds to the weight,
and consequently to their power of overcoming resistance on the
part of the fluid : if the pressure be oblique, and in -direction of
the motion, it will, besides increasing the weight, give impulse/'
The reason why this effect does not take place at sea, is supposed
to arise from the opposite inclination of the planes which com-
pose its surface. Bodies of different shapes, are supposed to
make different degrees of progress ; and that those used at sea for
finding the direction of a current, should be conical, with the sharp
angles at the base rounded off. Mr. O. then enquires, '* lastly ;
does a body floating down a stream or current, and which has a
quicker progress than the stream or current, receive any addition
to its motion from the motion of the fluid V This he thinks
ought to be answered in the negative.
\
Observaiwn8,''^Mr, Orr informs us, at the commencement of
this article, that his ** object is an endeavour to attain the truth on
so interesting a subject;'' and as our object perfectly coincides
with his, we hope to be exempt froni any accusation of " peevish,
ness and personality" when we express what, on the present oc-
casion, appears to us to be " the truth/' We shall, therefore,
begin our remarks on this paper by observing that it consists of a
number of notions on the subject, already published by himself
and others, and noticed at pages 132, 345, and 351 of our fifth
volume, huddled together with admirable confusion ; and expres*
sed in language so inaccurate and indefinite, as to be wholly unfit
for ** the discussion of philosophical subjects.^ This assertion is
supported by several examples in our quotations in the preceding
64 If r» brr tmJldaiiMg Bodies.
abridgement, and others are not wanting to corroborate the ge^
neral truth ; such as *^ floating on the surface more or less deep/^
Deep on a surface f *^ A cylinder with all its transverse diameters
equal, the other of a conical fo^m, with its transverse diameters
or lines all unequal/' Can Mr. O. conceive a cylinder or a cone,
the diameters of which are not transverse, or do not possess these
properties ?
We shall now take a view of this paper independent of its inac.
curacy of expression. A great part of it is employed in attempts
ing to prove, what bad either been already demonstrated, or needed
no proof ; and some of Mr. Orr's other positions appear to be ei^
ther defective or false. With respect to what he asserts to be the
cause of the accelerated motion of loaded barges, we must refer
to our former remarks on the subject, at page 134 of the dth
volume of this work. The assertion that '* all pressure on bodies
floating with streams must, whether the pressure be perpendi*
cular or oblique, increase their progress,'' is neither ruw nur true.
The former of these is easily proved by a reference to Captain
' Barney's paper, noticed in our fifth volume, acd the latter by re^
fleeting that (according to Mr. O's expression) the pressure may
he exerted in a direction oppasiit to that of the motion of the
floating body, and consequently will rather retard thata increase ita
progress. Mr. O. is not more correct in his supposed analogy be-
tween a loaded ship at sea, and a loaded barge floating with the
current : besides, independent 4)f the failure of this analogy, a
little reflection ought to convince Mr. O. that the cause to which
he has attributed the difference in the rates oi sailing between a
heavy and a light ship, has very little if any influence on the Hub^
Ject. Towards the conclusion oi th«8e observations «e meet with
the following sentence : ** Supposing A barge loaded at one end^
and empty at the other, and without a helm, if it floated in a fair
and regular stream, without Currents, it would certainly proceed
with its heavy end foremost, for the same reasons that a conical
piece of wood, or even a cylindrical one loaded at one erid^ would
go with their heavy end foi^emost in a fluid, tliough originally
placed in a contrary direction: it would be the same with the
cone and cylinder, if placed a«;ross a dry inclined plane ; that end
containing the greatest quantity of matter, from its power of over-
coming resistance, would always have a tendency to be fort^aost/'
By *^ a fair and regular stream" we understand Mr. O. to mean
one of which all the particles move in straight and parallel lines ;
if so, and a .cylinder with one of its ends somewhat heavier thau
the other, were placed with its axis exactly in the vertical plane
of its motion, with the lighter end first, we must ask Mr. 0«
what force, according to the mechanical laws of nature, could m«>
duce a reverse of position ? Nor does the analogy which is here^
supposed between the motion of a conical body floating dowa st
Mr. Orr ek jtoatwg Bodies. 6^
Ureatnand rollit\g down " a dr^ inclined plane," dt all subsist ; any
inore than the power of overcoming resistance inherent in the
greater enJ of the body, arises solelt/ from its containing a greater
quantity of matter, as Mr. Orr's language indicates. For, let us
Suppose a conical frustum, the density of which varies in the in-
verse ration of the magnitude of two indefinitely thin laminoe per*
jiendicular to its axis ; then it is evident that each of these la-
iiiiujB will consist of the same quantity of matter, and that if this
frustum were placed " across," and peitnitted to descend dowr> an
inclined plane, the greater end \v<)uld experience the greater de-*
gree of resistance from the medium in which it moved. Now,
tiircording to the hypothesis of JNlr. O. a^ each end contained an
tqual quantity of matter, ihatwliich met with the least resistance
ought to proceed first ; but will this be the case? certainly not.
The fact is, that while the body rollis, on account of the friction
of the plane, thfe laJ'ger end will be rimde to descend faster than
the smaller, and the body will theietore ultimately slide with this
Hid forehibsrt ; but in the case of the floating bodv, there is no
rotation, and thuS caus^ of a change of direction must vanish.
After the perusal of these remarks, we think our readers will
agree with us, that Mr. Orr does not possess either a 'very accu-
rate, or a very extensive acquaintance with the subject which he
has chosen for the exercise of his ingenuity. He seems to be
more desirous of diflusing around him what he thinks he has acs
quired, than anxious to grasp ^hat yet lies before him j or irt
olher words, much fonder of utififig ihati of reading ; tut we cah
assure him that the former is an ihdispcinsible requisite towards'
performing the latter with efl'ect ; and we would, therefore, aft
friends, advise him to niake himself well acquainted with the imi-
pulsions of wind and water^ and the invariable laws of mechanical
nature, before he favour the publick vvith atiother communication
on riiis abStrhse subject. We shall conclude these remarks by.
observing that Mr. O. in this paper, intimates his. intention of
attempting to dcmonsttate that it is principally owing to a differ-
etice of sliapfe that one ship saHs better than another That bo-
dies containing equal guahlities of matter, but of different shapes,
receive d.i^'erent degrees of resistance, when moving with equal
velocities through the same medium, has been b(!th tt70 long and
too Wf'll khown to herd any demonstration, notwithstanding the
partial exceptions made by Mi*' llomme : and this we are induced
to mention with a view of saving Mt. O. either the labour of his
task, or the moitification arising from its inutility when performed.
M'e iiiay observe, however, that if he can, in a simple and perspi*
hmus manner, demonstrate the ffvst form of a ship for bailing, he
will perform an acceptable service to the public, ahd be justly en*
titled to all that we, as guardians of science^ have to bestow — our
approbation and thanks.
2tOi 23, — TOL. VI. K
( 66 )
REVIEW OF SPECIFICATIONS OF PATENTS.
I
PUBLISHED ly THE REPERTORY OF ARTS, MANUFACTURES, &C.
During the Months of January j February ^ and March^ 1810.
Jl/r. John Leigh Bradbury* Patent for a Method of spinning
Cotton f FlaXj and IVooL Dated December 1 SO/. — Repertory of
ArtSy No. 92. Second Series,
In the method here described the fly with its arms pointing
tsp wards,. turns upon a vertical spindle« the bottom of which rests
upon and turns in a step fixed to the upper side of a rail which
supports it. This spindle passes through a rail above, which sup-
ports the fly resting on a masher. The upper part of the spindle
i3 smaller than the rest, and carries a bobbin, which is supported
by a shoulder on the spindle, at the lower termination of the
jimall part. A wharve or pulley is ilxed on the spindle, and aoo-
tber on the socket of the fly, each of which is turned by a band
from a separate drum ; the motion of the Hy twists the thread as
delivered from the rollers of tke machine,, and by means of the
thread it also turns the bubbiu. The draught or winding up of the
thread arises from the friction of tlui bobbin against the spindle ;
and is regulated by the rotary motion of the spindle, as imparted
by the drum fixed opposite its pulley ; and it may either revolve
the same way with the fly, or in a contrary direction, or may
remain stationary, as the quality of ^e thread requires. The pa-
tentee prefers the vertical positionyand observes ; " The principle
ofthis improvement, as distinct from the old mode, consists in in-
verting the fly, and giving it a separate motion from the spindle.
The improvement arises chiefly frora^ the ibllowing particulars ;
first, as the fly is the chief agent in twistii«g the thread, it is the
only part kept in rapid motion ;. consequently there is u great
saving of power, since, in the old machine, the spindb and fly
are turned together at the same speed. Secondly, the h^bin, fly,
and spindle, having their distinct and separate motions, the
draught or inclination of the thread can be regulated to the ut-
most exactness, and, when regulated, will remain invariably the
same at whatever speed the machine shall turn; whereas in the
old mode, a variation of speed produces a variation of draught,
thereby breaking the thread and causing much waste. Thirdly,.
on account of the inverted position of the. fly, the bobbin can be
taken oflf, and put on with expedition ; whilst, in the old plan it
was necessary to stop the spindle, and unscrew the fly from the
topy or to take out the spind^^. By these ini{)rovenients the quan.'
J
Mr, FohcVs Patent for cert am I'mprovcmtnti on Pens* 67
tity'of yam produced by eich spindle is nicarly double to that of
the old plan, witli the same power, and of any degree of fineness
required/'
Obiercafions, — In November, 1805, the Earl of Dondonald ob-
tained a patent for the same purpose as this of Mr. Bradbury :
it was described at p^^ge .97. of our third volume. The traverse
motion of the thread on tlie bobbiM in the present instance is ob*
tained by a vertical motion of the fly, as in one of the cases of
Lord DondonaldV invention; but the circumstance of giving to
each of the parts a distinct and separate motion, appears to be
neW| and is doubtless a very material improvement, as by it the
draught may be regelated according to the rate of spinning, and
much lewer threads broken than in Ihe common way. The rc»
^version of the tly also is calculated to admit the bobbins to be
changed with nmch greater facility than before ; and if the pa-
tentee's concluding statement rel/tive to the quantity of yarn
produced by each spindle be correct, this is certainly one of the
most essential improvements that has been introduced into the
machinery in use for spinning cotton since the inventions of Ark*-
Wright, unless the one denominated the mule must be excepted;
s=r
^
Mr. Fredeuick BAaLiioi.oMEw Folscii'* Patent for several
Imprwct mcnts on art am Machinvs^ Instruments and Pens y calcu^
lated to promote Facililj/ in JVriting, Dated May I8O9— iJe^^er-
t or If of Arts y No, S'2- StCund Scries.
The patentee states these improvements to be ^hreefold.-«-
" First, in having a valve acting with a spiral spring, or screw,
to fix it on the top of the pen, to supply it occasionally with air,
to force the ink into the socket of the pen. Secondly ; in having
a small pipe at the bottom of the tube to convey the ink into tb%
socket of the pen, through which it is forced by the operation of
the valve at the top of the tube. Thirdly ; in having a plate on
the front of the socket of the pen, to contain a supply of ink for
the nib, and to pi event the ink flowing t»)o freely into the rub."
This pen may be made of any sort of nietal, and consists of
three parts, viz. a lop, denominated a box; the middle part',
called the tube, and the lower extremity,- styled. the socket: it is
thus made in three divisions for the convenience of cleaning when
necessary, supplying it with ink, and prefixing different nibs to
the same socket. The top part, or box, has a bottom sc^dered into
it, with a h<\le through it to admit the air to pass into the upper
part of the tube. This box ccn tains a -spiral spring, and a small
rod which passes through the hole in its bottom, and has a valve /
fixed to it at the inside of the tube. One end of the spring is
festemd to the bottoro of the box, the other to a kncib wbich
screws on to the top of the small rod : tbe ipring, therefore,
presses upwards against the nob, and keeps the valve close lu the
bottom of the box, to prevent the ink Irom entering it from the
|uhe. The tube has a small pipe soldered inlo its bottoni to ad-
roit the iuk to flpw into the socket or lower part, to which it is
united by means of a socket joint. 'J he tochet is made hoUoWf
pnd has a small hole'in front, for iulm tting tht^ air and regulating
.the quantity of ink that it will Ijear. The lower part is made ii>
the shape of a conmmn pen with a slit nib ; and has a plate sol-
dered in its tropt- The lo\\^r end of this plate is iitle4- nearly
close to the^^ hollow of tlie nib, but IcU loose and iu a {-lasting dit
rectiou towards the point, and below the top of tlie sht up th«
nib, so that in writing thp nib binding it lets the ink pass freely,
but not too copiously, to the point of the nib." In scHiie of the
sockets the lower part is Qiade angular, and the nib has no slit^
but a small notch or groove at the end. The tubf also \\\Hy be
used without a box and spiral spring, by making tiie top pr knob
to screw on the tube, and having a hole through it within the^
screw part of it, which will admit the air by mfbcrewing the top
a littlft, and answer the purpose ot tho bo:^ and screw.
»■' I ■ ■ II I ■ I III*
• . 06»«Tffft'a«#.— Messrs. Folsrh and Howard took out a patent
for a similar object, about two months prior to the date of this,
and which we have noticed at page 3S1 of our preceding volume,
' These imprweniepts we think are justly entitled to the appella-
tion, and are well calculated to furnish a constant and regular sup-
ply of ink with very little trouble. Their object is to unite the
pen and inkstand, or bottle, in one instrument, and thus to aiford
on many occasions a source of convenience which could nototliei"-
wise be easily ol^tained. 'i'his object appears to have been inge*
niou^ly accomplished ; and the only objection to which it seems
to be exposed, is U)e drying ot the ink when long kf pt in the tube
'91- socket of thf pen.
'IT"!^" " '" ■ ' ' " nm^v^^f'^m
Jfr. Edward Manley'a- PaUntfor aVlough. Dated May I8O9*
— Repertory of Arts, No, Q3. Second i^Vrief.
Mr. Manley* denominates this the Expedition Fl&ngh, and states
that it *^ has this advantage over every other implenjent, that the
same horse-power hat more than double the eftect in draught, and
that the work it makes is greatly superior to that of every other
plough." It is 'Worked by a beam in the common manner, and
has three different sets of feet, which may be exchanged one for
another as ciccumstances render it necessary. The number ifi
paph of these sets vuries according to the extent of the beam,- and
Mr* Huiton'^ PaitHtfor a^Methoti ofmtdcing Sickles^ Sfc. 6g
the work to be performed. " The first set, when set shallow in the
ground, will eitbpr scarify or spine; when set deep, they will
draw themselves into the giound,. working it up and pulverizing
it at a great depth. I'he second are used for the purpose of work- '
ing the ground finer. The third are used for turning the ground
.over in single or douhle ridges. The beam or wooden frame in
which the feet aie fixed, represents that of the common plough,
' >vith the addiiioR of two arms or side beams to take the side feet,
and is worked by handles, and set hy a wheel, A foot of the first
set represents a coitlter, with a sharp pomt, having wings fixed
behind. A foot of the second set exactly resembles that of the
first, but is of a smaller size. A foot of tlie third set differs from
tbe others only,' in that it^has a single or double broad plate &xed
behind the couUcr."
Ohservations. — Mr. Manley claims a very great superiority for
his invention ; as far, however, as we can jud^e from its me-
chanism, from the plate accompanying the specification, we think
that the public will find it necessary to make a deduction from
his statement ; and this deduction wjll perhaps not be a very
small one when the land is stiff.
■wwp*y^—^— ■»■— — ^ I'll'" I' *»—*«
■ ■l II nm
ilfr- William WuTTO-s.^i Batait for a Method of making Sickles
. and Reaping-hooka, Dated July ISO^. '^^Repertory of ArtSy
No, 93. Snutid Series,
Ik tbe execution of this' method, Mr. Hutton directs that a
piece of steel be hanmji'red or rolled into a suitable thickness, and
made into the projjcr form for the blade of the sickle or hook*
This blade is then to be toothed, and tempered ' according to the
quality of the steel ; after which it is to be set and ground as
usual. When the back has been made and fitted to the blade, it
is to be fixed to it by means of either rivets or screws ; or the
back may be made double, and the blade driven in between its
liearly closed edges, and then screwed or riveted in order to fasten
it more effectually.
Obscrcaiums, — What advantages this patentee proposes to de-
rive from his in\'ention, we are at a lo;ss to discover : one disad-
vantage, however^ is obvious ; viz. the additional labour in the
construction of sickles according to this mode. The blades may
perhaj)s be made rather lighter, by Mr. H.'s method than in the
common way ; but it will be at the expeiwe of strength : tbe
weight being the siime in both cases. We apprehend that IMr.
H.'s object is, by making tbe blades only of steel, toetlect a saving
in the quaptity "of that metal \ but would not this have been
TO Mr. Barton's Patent for a Lamp of a nca Const motion.
equally effected by welding the iron and the steel together, of
which the sickle was to be composed I
Mr. John BARToy'* Patent for a Lamp of a new Constrvction.
Dated November iSQ9,~^Repertorif of Arts^ No, 93. Second
' Seiiet.
Mh. Barton's method of raising the constant and necessary
supply of oil, for the purpose of ieeding the wtck of the lamp, is
by applying the hydrostatic pressure of a fluid of greater specific
gravity than the combustible substance. 'I'he heavier Auid is
contained in an exterior reservoir, in which the lamp with its
contents and appendages is made to float. A communicatio«
takes place between the two Euids through an aperture at the bot-
tom of the lamp, and is permitted to flow into it as much as the
counteracting pressure of the combustible fluid it contains wiU
allow. By thus making the point at which the wick is placed
moveable^ by the continual subsidence of the lamp in the exte-
rior reservoir, as the oil is gradually consumed, common water
possesses sufficient specific gravity for the heavier body : and the
patentee conceives that by this and other improvements in the
construction, he has ** accomplished the end proposed with greater
advantage or convenience than the same has been hitherto done."
He then illustrates this prmciple by an example and flgure, and
afterwards describes one of t^ie lamps which he has e&iistrueted.
upon iU
The lawer part of the lamp consists of a cylindrical vessel of >
thin brass or copper, having its bottom prefixed eith^er by a screw-
joint, or in the manner of a snuff-box lid, for the convenience of
cleaning the interior of the vessel. Through the bottom of this
vessel, there is an aperture of about onc-teruh of an inch in dia-
meter ; and from the top of it, the tube which contains and feeds
the burners at its upper extremity issues. Above the vessel is '
fixed an air-tight vessel or float, nearly of suflicieut buoyancy to
support the lamp and its appendages in the heavier fl«id in which
it floats. * Another float is also fixed near the top of the tube;
and these together are capable of causing the whole to float in the
water^ or oth^r fluid employed to effect the hydrostatic pressure.
The exterior part of the lamp coi>tarns this fluitl^ by wiich a coc^^
stant supply of oil is, famished to the bnrr;ers, aud in which the
lamp floats. The bottom part of this exterior vessel which con.^
tains the vessel and oil, represeuts a pedestal, and the up^er part
a vase ; this cast is to be made of such a size that it may con-
tain nearly the same quantity of fluid, iudq)endent of the space
occupied by the float, and the tube passing through it, as the
vessel into which the combustible fluid is pat. It is al?a remarked.
Mr. Barton's Fattntfor a Lamp of a new CohsitruGtion* 71
that the lamp should be so constructed that the height of tbe
^.'oluain of oil, should be to that of the water by which it is sup^
ported, in the inverse ratio of the specific gravities of iht two
fluids. The tube which contains the oil is made to taper uf •«
wards : and about one half of iis diameter below its upper extre-
mity, there is attached a small plate or ledge concave upwards^
Hiid projected on each side of the tube, about one half of its dia-
meter. The intention of this concave plate is to receH't ^the
small quantity of oil which generally exudes from tbe wick of a
lamp that is well supplied. Another similar plate, but of larger
diameter, is fixed a little below this, and the tube is perforated
with a row of small holes just above this last, to admit the oil
which it may receive to be brought again into contact with the
wick, and to permit the external air to paiss through tJbese aper-
tures for the purpfose of increasing the combustion.
Observations. -^^V^'iitfex^t and ingenious contrivances have been
adopted by patentees to answer the end of furnishing a constant
supply of oil to tl>e wick, without having the light intercepted by
the vessel that contains the combustible fluid. For three of these
methods, see our ^nd and 3d voliiiaies, pages Z7 and Sd- llie
chief objection to these was tbe subsidence of the oil, occasioned
by the difference between tbe upper and lower surfaces of tbe
dense fluid diminishing as the oil >vas consumed by burning $ and
this objection appears to be in a great measure obviated by m«k*
ing the lamp with its contents float in the beavier ^uid« instead o^
being fixed at a certain point above it.
Mr. John Duff's Patnitfor Snuffers of a new and impnircd Con-
, itruction. Dated December \^0\)^^ JEiepeHory of' jirts. No*
93, Second Series,
In these snutrers,.a scraper turns on two'pivcHs, and » pressed
rapidly hack by a spring acting against it. This, force operates
against a prominent peg inserted in a valve as tlic door of the souih-
fers closes^ which raises the valve and permits tbe snuff tb >pttSft
into the receiver. This 'valve shuts again by >means of vts 4>w»
weight ; and the scraper being of the same size as the valve, it
acts as a second door to Ihe ^-eceiver, iintil it fs drawn back %j
tbe opening of the snuffers, when the valve resumes its former place.
One end of a piece of iron is fixed to the scraper, and the other, by
means of an oval hole^ is held by a peg fixed in one of tbe sbanJK
of the^ snuffers ; and on account of the shape ** of its aperture,
draws forward the scraper at the opening of the snuffers* aod
pushes it backwards as the snuffers close.'' Tbe receiver is emp*
tied by a door at the end, which is opened by pressing the point nf
yii Mr. EarrojCs Patent for improttment 8 in tVindoK B finds >
^ the snuffers upwards or downwards. This djor is fastened by a
spring on the inside. Two semioval cuts with sharp edges are
made in the point of the snuffers, for the more effectually removing
.Bpliuters or thieves from the wick uf candles.
Mr. Jamzs Bah Ron's Patent for Iwprovanents in the Apparatus
. vsfdfor Rollers far Wvidkrw-Blinds, Maps, and other similar 0/5-
jects. Dated December I8O9. Repertory/ nfArts. No. 94. Second
Series*
In this improved method, a bracket is fixed to each end of the ,
lath, and the roller suspended by two pivots, either cylindrical or
conical ; those of the latter kind the patentee prefers, as produ-
cing less friction. One of these brackets is a spring fastened to
the top of the laih, for the purpose of retaining the blind at any
part of the window where it is required. This Spring is regulated
or niade to act with a greater or less degree of force by a wedge
inserted between it and the top of the lath, and movecl by means
of a screw. This spring crtuses the pulley at the extremity ot' the
roller 16 press agi^inst a metal plate fixed to the underside of the
latb, and prevents the weight of the blind from running it down.
The blind is rolled up by pulling a string which winds round a
small spindle between two circular plates, m the usual way.
When this string is drawn down, the pressure of the pulley is
removed, dnd the blind rolls up freely to any required height ;
but when the force is removed from the string, the spring again
|>resses the pulley against the plate, and stops all further motion.
One of the brackets may be made 10 slide outwards, to admit the
pivot to be withdrawn, and the roller to be taken down for the
purpose of cleaning or preserving the blinds. In this case the
bracket is made to slide in between the lath and a metal plate
attached to it ; and is retained to tfie pla£e by a staple at its outer
^nd, while the other end has a bracket and a button which slides
through a slit in the plate, and keeps ^ that end steady. For ad-
justing the pivots with greater nicety, one of them maybe made
to screw through the 'brackets, by which means the inaccuracy of
the workman who mounts the roller can be corrected if necessary^
Obseroathns.'^We see fto material objection against the im-
provements which Mr. Barron has made on this subject: they are
simple, and if execulcd with care, are capable of answering the pur^
IKwe for which they were intended, very well.
73
Mn George Pocock's Patent for hit Indention of Geographical
Slates for the Crnistructhn of Maps. Dated June 1808. Rvpert(/ry
ofArtHy Ao, 9**} Second Series.
Tills mvention consists in drawing liiieli of latitude andlongi- .
tude, or other lines qn slates, to serve as guides to learners .of '
geograpliy in sketching the ditfcrent parts of the earth's suiface.
The method of describing these lines on the slates which the
patentee has adopted, is that of drawing the longitudinal lines oi
the globe upon a thin plate of metal, and cutting out the alternate
spaces. This plate will thc-n serte as a ruler by which thelon»»
gitudinal lines nmy he traced upon the slate, by a sharp points
tool, or other proper iostrument. The lines of latitude mftj be'
described in the same manner by another siiniliar plate.
The specification is accompanied with a drawing, representing
the lines which are proper to be indented on a slate for preparing
a map of the eastern and western hemispheres ; and slates for maps -
of any particular parts of the world are to be prepared with »p*
propnate lines^ according to the kind of map required.
Observ at ions. -^The political and commercial relation which
subsists between thiscountry and almost all the other parts of
the globe renders geography a necessary and iudispensiblc part of
a liberal education. Many experienced teachers of this science
conceive one of the best methods of impressing the outlines of
diflercnt countries, as well as the local circumstances of particular
places on the mind of the youthful student, is to cause hmi to de.
lineate them in their relative situations.
For this purpose, outline maps .have been adopted by some, and
those with the different lines only by others. The idea of trans-
ferring these to slates was very simple and easy, and is well calcu-
lated to facilitate the attainn)ent of the desired object, both as it
will eftect a considerable saving in the expense, and as it admits of
the wouk being d<efaced and renewed at pleasure, until the requisite
degree of correctness be accomplished.
J/r. Joiix 3 O'S t^*s' Patent for Improve/^H'/its in the manufacturinfr of
S kelps for Fire Arms, Dated November I8O9. Repertortf of Arts ^
No, 94 Second Series,
TuK patentee states that the principle of his invention consists
in nmkiug plates of iron in a tapetlike form, and of sufHcient size to
be c ut into several skelps : so that the grain or fibres of the iron
iQay be drawn transversly in each, instead of longitudinally, as in
4he present mode. To effect this purpose, he directs that a piece of
xo. 23r— A'OL. VI. X . '
74 Mr. Jones*s Patent for manufacturing S kelps for Fire J rmu
Von of a wedge like form, proportionate to the length and numbef
of the skelps intended to be manufactured from it, be bleated to the
usual' degree, and then rolled by means of the common apparHtus
used in that operation, so that one edge of the plate may be thicker
than the other ; their dltl'crence depending upon the kind of skelps
wanted. This thick edge and taper-like form, he thinks, will be
best produced by rcducmg the circumference of one and of one or
* both the rollers us^d in the operation ; or nearly the same effect
may be produced by a pair of cylindrical rollers, by giving one
end of the upper roller more play than the other. The plate is
then to be divided, from the thick edge to the thip, on the contrary
way, into pieces proper for making the skelps : but in order to
prevent waste in cutting, the pieces may be cut about the width
of the muzzle of the skelp ; hence the' plate must be formed ra-
ther thicker on the thick side, to admit of being widened towards
that end by means of a tilt Ijammer, or any other method. The
skelps mayalso be made in different lengths, and welded together
either in the barrel or skelp form. Barrels manufactured fronn
skelps of this^ kind are said to be more free from grays or flaws
than those made in the usual manner ; and this is attributed to a
greater degree^f pressure while the iron is very hot, which causes
the pure particles .of the metal to cohere more closely together,
than can 'be ejected by the strokes of the tilt-hammer under a
less degree of heat. The grain or fibres of the metal also *^ being
by this process laid round, parallel to the edge of the breech,
they partake, in some degree, of the nature of what are termed
twisted barrels^ gain a considerable addition of strength, and con-
sequently stand proof with less ri&k of bursting."
Odservations.^^Severdl patents have been obtained within a
few years, for manufacturing the bairels of firearms, an may be
seen by a reference to the different volumes of this work. One of
these was granted to this patentee in I8O6, for an ingenious method
of making^ twisted barrels; and upoA which this set forth in th«
present specification appears to be an improvement, by bringing
the fibres of the metal into an entire transverse, instead of a spiral
direction. By this mode of manufacture the gun barrel may be
regarded as composed of an indefinite number of endless rings of
very fine wire, connected together into one mass ; and each acted
upon by the force of the powder at the moment of explosion, in
the direction of its length ; and every one who is conversant v^ith
the nature and properties of iron, will readily conceive that this
mass is capable of sustaining a much greater force, in this way,
than .when it-tends to separate the fibres of the metal longitudinally.
Wle ane;.thersforey inclined to think well of this method of manu-
fi^ptiice,. and conceive that if it were generally acted upon, and
carefully executed, it is suscfeptible of coi^siderable utility.
( 75 )
Mr, David jMeade Randolph* Patent for certain Improrements
in the Constructkm of IVhed Carriages vf every Dcscriptiop,
Dated November I8O9. — Repertory of .Arts y No, 94. Second
Scries,
This specification is chiefly occupied by descriptions, of tl^e
figures by which it >is accompanied, and as it is of coosideraiblQ
length, and the figures are ninuerous, it would much cxcw^^ the
limits of this work to give a n^inute description of all the parts;
we can, therefore, only insert a few of its general principles, 4iad
refer to the Repertory of Arts for further particulars.
In a four wheel carnage intended for a mail or. stage coacb^
Mr. R. describes a contrivance which serves for a front seat aod
step alternately. In tl\is coach tiie window also slides back Uorv"
zontall}, and is furnished with bolts at the bottom, to prevent tue
door from opening, when both are shut. A hook or joint isiixed
in the vertical jilane which bisects the fore axletrce, for attacliii>g
a pair of swingle^trees, by which the hind horses draw. At tnc
. back of the coach, and at the same distance above the plane of
the axletrees, whjch makes an angle of three degrees with the
horizontal plane, as the hook of the seat of the outside passenger
is placed ; and the inside seats are adjusted to the same inclina;-
tion. The back part of the body of ihe carriage projects over »
the heads of the outside passengers, and a curtain of piled silk or
other proper material descends from the upper, part of the projecr
tion to defend them from the weather. The fore part of th^ dri»
^ver*s seat is perpendicularly over the front axletree, " which j
from the wedge form of ihe platform and body, when the scat
shall contain two or more, the load is' to be adjusted so, as nearlji
as may be, to impose upon the hind axletree two-thirds of the
load in all cases.'^ A check spring is also added to aid the others^
and'to limit the repulsive effect of all sudden shocks. When the
carriage is intended to contain only one seat witjsin, like a post-
chaise, the bind wheels are made lower in consec^uence of the pole
being shorter, in order to preserve the three degrecg.of inclination
as before. The shape adopted for t,hi$ carriage is tha,t of an acorn.
** The door opens 19 front and directly behind the driver's seat, who
conveniently opens and shuts the sapie.^ The steps are fixed on
each side of the door« The construction of the platform and car-
riage part of these machines, are next explained and illustrated by
figures. *' Common waggons, with or without springs, to be made
vitb three perches, and double bodied and heavier carnages, or
carnages for conveying heaviest loads also, or with only one and
^ings ; in all cases, rolling different tracts and preserving tlie
wedge form ; and as far as may be, two-thirds of the several loads
76 3Ii\ Randolph's Patent for th CosstruCtum ^ffVktd Cwrriegea.
upon the hind axletree. All such waggons, coaches, or other
four wheel carriages being dra\»n in like nmnner ; to wit ; a tri*
angular tractor jointed at each end of the bolster, rising to a line
with the horse's breast, or a little below it, and swingletrees as
aforesaid, precisely perpendicularly «>ver the embreu^e of the pole
by the futchels, thereby providing draft in unison with the lift of
the front horses by a pole, or a unison of a lift and draft, more
particularly necessary wLen drawn by a pair of horses only, or
even by a single horse, which is to be done by the use of a pair of
shafts instead of a pule/'
Mr. R. then describes the construction of a particular and novel
kind of waggons ^nd carts. The carriage part of ihtese, however^
does not differ from those already described, but the bodies rest
and traverse longitudinally upon segments of circles, the radii of
which are eleven feet each. These segments are supported
by springs, or are bolted to the axletrees ; and one divided into
three spaces, into which friction rollers are introduced. To the
front of these carts or waggons, a vertical segment is tLccd for the
purpose of attaching a pair of shafts to, which are stayed at the
point of traction by a strong spring. " for the construction of
frames and iron rail-way waggons, the front wheels of the front
carriage roust be six inches diameter, the hind ones adjusted ac-
cording to the length of the body, so as to elevate the centre, and
form ^ line of inclination of three degrees, descending from the
hindmost wheel of the whole series through theii axles, and those
of the front ones aforesaid." It is also stated that in the cop--
struction of such trains or rail-way waggons, the diameter of
each axletree is * not to be less than pne-eighth of that of the
wheel ; the bearing of the axletrees in the boxes of the wheels,
length of naves in the clear, and the bearing of the wheels ou the
raiUway or road, c^re e^ch to be equal tp, the diameter of theaxle^
. As an improvement in the construction of all carriage wheels,
the patentee observes that all sho^]d have £\n unequal number of
spokes. A method of constructing wheels with cast iron naves,
and a double set of felloes, the inner being wood and the outev
cast iron, is next described tuid illustrated In this constructiop,
when all the parts are duly prepared, the combination is effected
by gently screwing the whole together, as far as the accuracy of
the workmanship may {permit ; leaving it to be consolidated by
tightening the screws from tiipne to time, as the workings may
render necessary, until the ends of the \vedge bolts which pass
through the felloes, be drawn even with ^be external face of the
cast iron segments or tire of the wheels. A screw with a proper
bead is inserted on each end of the axletree, to coniine the wheels
on the same.
The same principles are applied to the coftstruction of gigs, cur-
Mr. Rcmdolph^s Patent ffrr the Consttuciiun of Wheel Cani^gcs. 77
rides, cin(i all oilier tWD-wheeled Carriages, as well as to artillfry
carriages, and all other* with fi>ur wheels. ^A description is like-
wise given of a road scraper, or earth porter, adapted .to the pur-
pose of scraping soft matter, or removing loose earth, after it has
been prepared fur the purpose by ploughing or digging : for the
particular shape and constriction of which, as well as of the other
macliinery described in this specification, we must refer to tiie
original and the plates.
Observations. — A variety of essays have been written on the
theory of wheel carriages, and different opinions maintained rela^
tive to the best modes of constructing them, in order that a givca
weight may be drawn along with the least force possible, t>om«
have recommended the fore wheels to be made lower than the
]j.nd ones, some that they be all of equal height, and others that
the hind wheels be the least ; general practice, however, is in fa»
vour of the first of these methods. JNlr. Randolph's mode of
constructian also coincides with it, as he directs, that the plane
passing through the a3^i«of the two axletrees be always inclined
forward to the plane of the hori£on in the constant angle of three
degrees, whatever be the height of the wheels or the length of the
carriage. We should have been glad if he heul favoured us with
his reasons for giving the preference to this angle ; 'and stili more
so if he had deinoti&traied its superiority above all others for an^
swering the desirxfd purpose. Mr. Lambert, in an essay on four
wheeled carriages, published al Leipzic in the 2nd volume of Hin^
denburg's Archiv der AJathematik, in 1795, has shewn that the
thickness of those parts of the axles, upon which the wheels turn,
should be proportional to the diameter of those wheels, and that
the centre of gravity of the loaded carriage, should divide the dis-
tance between these axles in the inverse ratio of the cubes of their
diameters* It has also been previously observed, as well as in the'
present case, that about two-thirds of the whole weight should
rest upon the hind axletree ; hence, according to I^Ambert s states
ment, the dimeters of the wheels should he nearly to each other,
iu the ratio of 4 to 5 ; as the cube of the former being 64 and the
latter 1$5, which are nearly as 1 tb i2, or the distance of the cen-
tre of grg^yity from the larger wheels, coual to one-third of the
whole distance. This proportion for the diameters of the wheels,
however, does not agree with Mr. R's angle of inclination, except
the distance between the axletrees exceed 9i feet, 'i'lie circum-
stance of making the wheels to roll in dii^'erent tracts, (the fore
axletree being shorter than the hind one) has also an evident ten^
dency to destroy the angle which be recommends to be constantly
preserved, wherever there are ruts made by wheels that follow
the same tract as in the common mode ; for if the fore wheels be
caused to run in these ruts, the angle of inclinatioa will be in«
•7 Afr* Randolph's Patent for the Construction (ffVhcd Carriages,
creased, and if the hind wheels assume the lower path, it will be
diminished. One of the principal objects to be kept in the con-
struction of four wheeled carriages is, that each pair of wheels may
require the same draught ; this, however, wc think Mr, R. can
not prove to be etlected by his mode of construction ;. since what-
ever be the line of tract. on of the fore wheels, that of the hind
wheels (and particularly so when the body of the carnage is sup.
ported on spriiigs) will be the line joining the centres of the two
axles ; and this iiuikes an angle of three degrees with the hori-
zon, and c6nseqijent ly presses the wheels that support the greater
part of the weight upon an obstacle rather than iifts it over it.
Another object to be attended to Is, the diminution of friction be-
tween the wheels and axletrees ; Mr. R. directs that the naves
be n^ade of cast iron, and the axletrees of either wood or iron. It
bas been proved by the experiments of Coulomb and others, that
the least friction is generated when polished iron moves upon
brass : the axles should therefore be made of polished iron, and
the bushes in which they move of polished brass ; in order that
the least r^tardive force may arise from this cause.
The addition of the check spring which this patentee makes use
of, we think will prove an advantage, in both regulating the nK)<»
tions of the others, and assisting in diminishing the draught. Mr,
Edgeworth, in an essay on this subject, published in the Transac-
tions of the Royal Irish Academy, for 1788, oUsenres on this
head : '^ I apprehend that it is not at present commonly imagined
that springs are advantages for this purpose ; nor would it at first
sight appear credible, that, upon a ri>agh paved road, such as are
common in Cheshire and other parts of Englapd, a pair of horses
could draw a carriage mounted upon springs with greater ease
and expedition than four could draw the same carriage, if the
Springs and braces were removed, and the carriage bolted fast down
to the perch." The reason of this he states to be, that the springs
allow the wheels to pass more gradually over the obstacles with
which they meet in their progress along the road. There is ano-
ther effect however, which appears to have still more influence id
the progressive motion of such carriages, than this stated by iMr.
E. their elasticity causes the carriage to bound upward ^very
moment through a small space. * Thus its gravity is for that mo-
ment, in a gieat measure counteracted, and the progressive motion
which it has already acquired, is at liberty to act more freely in
pushing it forward; for'were it possible to take away the horses
instantaneously from a carnage mounted oa springs, and
moving with considerable velocity, it would continue for some
time to move of itself; the weight in this case acting as a fly
upon any mechanical engine, by means of which the machine ae*
cumulates a certain quantity of power, and will keep itself in
motion for a considerable time after the band is taken away.
Mr. DumbeWs Patent for a Method of Flax-spimiiH^. 79'
the weight of all carriages indeed has some efi'ect of this kind, or
the draught would require an intolerable exertion of force to ketip
them in motion ; but the effect is much the greatest in those
with springs.
Mr. ^mis'Dv'MJiiiLL.sPatcntfor a Method or Methods ofFlax-spln-
ningy and of prtparing or f/ia/ci/tg a species qfVarist^ Thready Fur*
7uture^ Cloth, TriUsy or Attire, which he calls Telary Teguments^
from Sil/cf Wool, Cotton, Flax, Hempy or Torr, a.i trelt as from a ve-
ry great Variett/ of other Articles, in a combined or uncombincd
State ; and for a Method or Methods of rcfahricating or renovatintr
the same, and of producing or reproducing from Tatters in general
a new Bod I/, Dated August 1808. — Repertory of Arfs^ No,
S4. Second Scries,
Instead of presei*ving the vegetable fibres of the flax to be ma-
nufactured as long as possible, and spmnmg the same by the com-
mon methods now in use, this Patentee cuts the matJeriali into
such lengths as may render them fit for being manufactured by tlie
machinery in comn)on use for spinning cotton. For the purpose of
thus preparing the flax or hemp, he ma"kes use of the common agri-
cultural machine denominated a chaff-cutter ; and in order that the
bottom and angular parts oi the flax may be properly cut, he caus-
es it to rest upon a thin layer of straw, rushes, or reeds, or other
similar substance, which in consequence becomes cut along with
the flax. These inconveniences may be remedied by making the
containing box of the cutter of a circular or other curved form ^ or
by any other suitable means. Mr. D. also further prepares the
said materials and renders them finer and more soft and flexible
by pounJing, rolling, steqiing, macerating, or by any other suitable
means, and then spins them by thesame engines and in the same
manner as cotton is spun. He also uses the abo^e mentioned
materials either in a separate or mixed state, as circumstances
may require. He likewise states that the materials are rendered
more fit for spinning by being subjected to a " strong pressure, with
or without the application of Iieat at the same time, by means of
presses, cylinders, or other instruments."
With respect to the ref.brication of the different articles, Mr.
D. divides them into shreds or. stripes, and again cuts those into
short lengths, and then reduces them into a loose staple fit for
spinning, by any of the methods before mentioned, -or by any other
niechanfcal means best suited to each sepafate kind of materials*
Obsavations. — A very considerable part of that superior degree of
strength which linen yarn possesses over that fabricated from cot-
Ion, undoubtedly arises from the greater continuity of the fibres of
M Mr. Mantous Patent for mi impruced Gun Lock,
whkh it is composed, Mr. Dumbeirs object is in a >^reat niea^
sore to destroy this continuity, for the purpose of subjecting *,he
materials to a particular mode of manufacture; but it ouglii \^^ \>t
remarked, that whatever he may gain in facility of extcutiun, will
be deafly purchased at the expense o( qualitt/. We cannot th^-re-
fore, but regard this Patentee's process as a retrograde step in
the progress of improvement ; which is to meliorate the mode of
manufacture without injuring the quality of the substance manu-
factured.
Whether or not the refabrication of the old materials wilt be at
all beneiicial to the public, is a question which we shall not attempt
to decide. It is, however, evident, that the yarn produced from
tbcm< must be of very inferior quality, while the expense of ob-
taining it will be increased. It will also greatly interfere with
the manufacture of paper, which has now become almost equally
as necessaiy as that of cloth, and in which the scarcity of materi<«
als has been a subject of considerable complaint.
Mr. John Man ton's Patent for an improved Lock fot
Guns and Pistols. Dated Decembery 1809. Repertory
of AriSy No^ 94, Second Series^
In this improved lock, the hammer is fixed to the plate by the
the same screw which fastens the hammer^spring on the inside ;
and the hammer-spring pin comes through the plate about |ths
of an inch. There is a small projection in this spring which
enters into the shank of the hammer, and Causes it to return to
its jointing with the pan when the lock is brought to half cock*
The cock is flat on the inside, is about one eighth of an inch
thick, and passes between the plate and the hammer when it
comes down. I'he squares of the tumbler are rendered stronger
and more perfect by a bulge which is left on the bteast of the
cock. ** When the cock is struck, down, the flint comes in con-
tact with the hammer face near the end, and forces it down suf-^
ficiently to admit the sparks into the pan. The pan is about
three -fourths •r seven-eighths of an inch long from the outside of
the plate/' The inside of the pan is round, and of the same size
X from one end to the other. . The end of t^e» stud in the main
spring is bevelled to fit under the nib, to prevent it from rising,
and the. crane of the tumbler has a roller in the end, on which
this spring operates. The bridle has a strong leg on the inside,
< and a stud which fits into the plate near the sear nose, to prevent
it from twisting ; and the sear shank is nearly vertical, instead of
being horizontal, as usual. The sear spring acts on a shoulder
left for that purpose ; and the pan is primed from the touch hole,
by the compression of the air ;n loadiiig. At that end of the
0 n planttng Farxht and otktr Trt€s. -, '^^
hatnlner fac« nearest the pan, a email groove is sunk iti the
.bamuier, to carry off any wet that may come down upon it* >. . .^
. TliQ patentee states the fol]owing as the principal advant^c|l
ivhich are derived from t^s improved lock. First; the pan
being solid with the plate at top, protects the prime. from wcC
Secondly ; the hammer opening downwards, and the flint acting'
in a direct line with the pan, the sparks communicate quicker to
the prime. Thirdly ; the hammer returns to its jointing wit&
the pan when the lock is brought to half cock, without any addi*
tional trouble to the user. Fourthly ; the Ibwness and compact*^
ness of the lock altogether rendf^r it much less difficult to protect
from wet, and much less liable to accidents; by catching in
cover shooting, than locks of the present construction.
O^^eiTafioRj.— -Different contrivances have been adopted with
a view of rendering the use of fire-arms more certainly efficacious,
and less liable to accidents. Mr. George Dodd invented a simple
gun lock which could not go off at half cock, and by which the
danger of missing fire, by the tumbler catching at hcflf cock, was
prevented. See our first volume, page 63. Mr. Noon lately ob>-
taiued a patent for improvements on fire-arms, the chief of
which tras that of protecting the powder from getting w«t.
This was noticed in our fifth volume, page 379^ It WifH readily
be admitted that these advantages which this pat^bte^ bad spect*
£ed as resulting from his improvements, are worthy of being
attended to in the construction of fire-arms ; and,' as fieur as we
are able to Judge from the description contafined in the .specifica-
tion and the figures by which it is illustrated, we conceive that
ihty may be &rly expected, as consequences of the method he
has adopted.
i^ii I nil I legBgagMfcR
AGRICULTURE.
On planting Forest and other Treeg, By A. C. R., ofCa$^
tie Combe. — Agricultural Magazine, No. 30.
The method of planting recommended in this paper, which is
seated by the writer to ha<re been f6llowed with much' success/
consists in digging each h6l^ for receiving the trees large enough
4o receive the roots freely, and in then laying the sweard, which
ts paced off, at the bottom of the hole with the grass upwards^
^ad setting the tree upon it, placing the roots straight and regu-
lar as in their natural growth, upon which moie sweard is to be
hud with the grass downwards, and the hole filled tip with earths
On clay ^oHs it is stated to be improper to go bdow the giiotf
i^o. 2^3. — VOL. vr. K
M Oil the Anglo'Mcrmo Quesiim*
ibould, thoagh it be ever so shallow^ and to be hj^tter to raise
earth a foot or two above the ground upon the roo^ •f the new
planted trees, than to go beneath the surface of the clay ; and >n
a few years the extra expense will be amply compensated
by the flourishing state and healthy appearance of the trees.
Obsarvations.'^Thes% remarks, though not new, are certainly
ingenious; ^nd without some attention to the points recom-
mended, little success can be expected in planting upon clay
soils.
On the Pfice of Anglo Merino Wool, By Benj. THOMPSOif,
of Redhill Lodge^ Notts. — Agricultural Magazine^ No»
30.
This paper states the quantity yielded, and the prices obtain*
ed for fine wools by Lord Manveis and the writer, in the last
year. The Ry eland sheep of Lord Manvers yielded about two
pounds four ounces each of wool, which brought 3«. Sd, per
pound ; the Merino-Ryelands of the first cross yielded not less
than three, pounds and a half, which was solA for Ss, 6d, per
pound. The writer's own wool, which was one third part pure
Merino, one third part Merino-Ryeland, anyone third unmixed
Ryeland, brought six shillings per pound weighed together ; and
this was about twenty five shillings for each fleece. Fr(fm these
•premises the profit of fine wool is inferred to be deserving the
notice of agriculturists in general.
OSser^ations, — The price of fine wools has been so exceedingly
variable for the last eighteen months, that no general conclusion
ought to be drawn from what they sell for at any particular peri-
ods ; but it does seem that the woolbuyers are unwilling to give
a proportional advance for very fine wools, and as long as this
continues, their production will necesssarily be limited in this
amnftry*
On the Anglo'Meriiio Question. By Aoricola Northumbki£N-
sis. — Agricultural Magazine^ No. 30.
Obteroations on the speculative ojm'ons of Mr. Thompson ; and
experimental evidence of' Mr. Wright and Mr. Hose. By John
HuKt, of Loughborough.^^Agricultural Alagatiney No. 3!l.
The first of these papers is a continuation of the long pencting
controversy relating to the superiority of the Leicester and Me*
On ike CuUwre of Carres. t)
ri&o brteds^ sheep ; and the latter consists of comments on aa
account puHlhecl in a Leicester Newspaper, of some experiments,
conducted by Mr. Wright of Pick worth, to which we^ormerly
alluded, and which we had hoped would have terminated this
tedious controversy : they appear, however, to hii\e been con--
ducted in a very unsatisfactory maimer; and tiie subject may
still aiford matter for the Agricultural Magazine,
On shoeing ^the Ox and the Morse. Btf Clericu8, of Buckirfg*
hanuhire, Agricultural MagaztnCf No, ^l.
This paper is a desultory and whiniiig lan^entalioii over the
difficulty of finding blacksmiths to shoe oxen, in a neighbourhood
where they are not commonly used, and a complaint cNf the pKJtt^
dices entertained against them by the common labourers in hu8bali<-
dry . — Relative to shoeing the horse,, the writer says, ." one great
object is to preserve his feet as nearly as possible in .th« state Ju
which they were found at his first shoeing; . and to suffer. .tht
smith .to cut not an ounce mora from th^o than ^s absoluteJj
necessary for fixing opot the shoe/'
Observations, — It is difficult for us to conceive that the desire
of seeing himself in print of the most vain author would not have
been restrained by the most common discretion from sending to
the press so silly a production. /
■^!9SafB^*B99B9^B9qq^q!nR^BinBSBBaS9BBB9BB9BS
On the drill Culture of Carrots. B^ R. S. D. of fFindsor Forest.-rr
Agricultural Magazincy No, 3\,
On the Culture of Carrots, tit/ A.^N. F. of Worksop.-^Agricultural
Magazine, No, 32.
The fif St of .these papers contains little except common place
observations ou the benefits to be derived from the culture of the
carrot, and a suggestion that they might be drilled on light soil
to advantage, if any method were known of separating tlwB^edfi;
so that they might be regularly delivered by the machine : and^tl^e
writer closes by soliciting information on this i^oint.
The second paper is in reply to these enquiries, and contains
an account of a ji^ethpd which .had been practice<l with greEtfsuc-
cess upon a san^y ^pil, tolerably free from couch grass: The fieM
vifas ploughed in oojQ-bout lands in the month of Maich or April,
by which an additional depth of soil was given to the line for the
carrots, and the ,seied was imiiiediately sown by band* upon the
middle of each la<id, where, being much higher than the furrows
they were much ^easier- weeded, as well as preserved for winter usfe.
These row? were at, two feet distance ium e*ch other; arid in Jliiie
jl4 Hints relating to etn Improvement on the Thrashing Machine^
the intervals, which had been kept clean from wee(ls,^were so^n
\Vitb turnips, and the turnips drawn off* in autunan as wanted for
fattening sheep. The tops of the carrots were mown off, and be-
fore winter, part of them were drawn, and laid between two rows
Itfft standing, the part drawn being regulated by the quantity ne-
(fessary to fill the interval wiih a single course, and tben the
whole was covered with soil only, taken from the outer side of the .
rows, and ridged up. ^Tbis method was found to Keep them per-
fectly well iu all seasons, t}iough before it was reported to the
wrhole crop was frequently lo^t, whether housed or not.
Ohservations. -—Th^ yfcry simple and easy method pointed out
in the last of these- papery is well deserving the attention of all
farm^rS) who grow carrots for winter use ; and we are inclined to
4iiink that the same plan might be advantageously applied to the
t>reservation of turpips in a severe winter. And though the most
advantageous plan appears to us bbvious enough, yet we trust we
-shall' bie' excused for remarking that the turnips need only be drawn
t)etween'thote rows where the carrots are intended to be stored, and
may be left to be eaten off by sheep in the other pairts of the field.
On coteriTff^s for Hay and Com Ricks » By Economic us, ofAylcsr
. iury.^r'AgncuUural MagaitnCf No. 31.
The writer remarks the great benefit arising from covering hay
.^nd corn stacks in unsettled weather, and recommends the use 6f
oid sail-cloth, as bestfitted for the purpose ; a practice very comr
mon in Kent and Surry ; and he conceives, that from the increase
of inland cemmunlcation by canals, it might be obtained at an
;fasy price in most parts of the country, • •
Observations. 'r^Thi^TQ can be no doubt of the propriety of this
recommendation, but the measure has been long adopted by most
intelligent farmers.
m^0m^^mm II il |i I ■ ■
Hints relating to an IniprovemcrU on the Thrashing Machine. By
Alexanper Scott, df Ormiston. -^Farmer* s Magazine^ No. 41 . *
To remedy the inconvenience frequently found to arise from
Veaking the straw in such a manner as to make it unfit fdr
thatching, it is pioposed to select all the tallest and best stand-
ing corn in the field, and bind it regularly with cords to be set
apart for that purpose; and to annex to the machine a foot- bar
pr treadle in a coavenitnt position for the person " who feeds the
/rorn to the machine" to set his foot upon at pleasure, and thi^
^fpN^P. t<>; b^ w cpnpt^cted with the feeding rollers, tha^ he cin
Frtparatorf Siep to ph/dwg Thum Hedget. '- U
jslcvate or depress the upper one at pleasare,so as to let tbe straw
pass quickly through the machine, or retard its progress if that
should he necessary for perfectly getting out the com.
Observations. — As hitits these remarks may lead to sonie prac«
tical improvement in the mind of some other agriculturist; but
we do not expect it from Mr". Scott, unless he is more fortunate
ill explaining his ideas, than he has been in describing the mod«
of applying the treadle alluded to.
a^fmm^^^J^'^mfi'^S^iBBI^mi^Sm
On the Potatoe Curl. Bj^ James Inglis, of Parkholm, near G/a#-
gmp.'^Farmers Magazine y No, 4i\.
The \yriter having communicated his opi^iops on this subject
in a former iQagazipe, relates the foUowing experiment, which he
made last summer. He fallowed a small part of a field in 1808»
and in August sprinkled it oyer with hot Ume shells, in which
state i^ l^y till tbd following April, when it was planted with
potatoes. On an a^j^ining par); of the field some potatoes wer«
planted in rovys, atn4 each set covered wijth ^little soot, and tha
rest of the field was planted oi> the dupg only which had been
laid upon the fallow. The result was, that those planted on the
lime, and with the soot, were entirely free from the curl, while
^mong those planted with dung, apd the san^e seed, there were
some hundreds of diseased plants. This experiment is considered
As clearly to prove, that the disease is local iand^hot hereditary.
Observ(ftions, — ^The mode in which this experiment has been
conducted seems decisive of the question which the writer was
desirous of )jringing tq issue, and affords a useful lesson to those
who cultivate potatoes on a large scale, by pointing out the
means of averting one of the diseases most injurious to that ve-
getable.
-VArowi
JTir
An useful preparatory step when Thorn Hedges are to be planted on
• Clay Soils, By 5onjr Reid, ES'q, of Castle Hill, near Kilbride.
Farmer's Magazine, JV^. 41.
This preparation is to lay an under-^rain of small stones im*
mediately ben'eath the line in which the sets are plated, so that
^ey may always have a dry soil for the roots to shoot in. And
^here old Hedges want improving in such soils, it is recommendr
^ to pass drains underneath them, at no very great distances^ in
a <^ross direction.
86' On ihe,imttilk|f^ofph^eltmg PoUitoe BloHomif
Observations. '^■^Thtre can be no doubt but that the advantage
rfisuking .from obtaining a thorn hedge^ in clay and wet soils, in a
short period, will more than compensate the additional expense
ot the drain recommended; and there cannot remain the smallest
doubt of the efficacy of the plan.
Estimate of the Expense of enclosing by Hedge and Ditch. By
R. G. of Perth. — Farmet's Magazincy No. 41-
On the expense tf endomg by Hedges, By Calc[jlato&9 of East
Lothian, — Farmer's Magazine ^ No. 41.
These papers consist wholly of calculations relating to the
subject of them. The result of the first is, that the loss of ground
by this fence is, in all cases, more thai equivalent to the differ-
ence of expense of this mode of fencing: and the other also fn-
vours the same conclusion.
Observatians. — As these calculations are adapted to a district
where stone is plentifol, and where hedges are not raised without
much difficulty, it should be remembered, that though the propo-
position may ht particularly^ it may h€ not generally , true.
OT«cae!=m
Q^^ the inutility of pl,utking Petatoe Blossoms. By the Reverend
Charlss FiNDLATEa> of Netplands. — Farmers Magazine ,
No.AU
The theory, " that in regard to animal or vegetable nature,
the given quantity of the vis vitae, if confined to a single purpose,
should exert itself more strongly within this limited spHcrt?, than
when it is allowed to expand over a larger field of occupation,"
having by its plausibility obtained some followers, and various
facts in the vegetable world appearing to confirm such a suppo-
sition, such as the disencumbering fruit trees of their superfluous
-wood by pruning, to the apparent increase of their prolific powers,
9^d the destroying the seminal parts of tobacco to obtain, the
more nourishment for the leaves; an anonymous article had ap.
peared in one of the ear ly^ numbers of the magazine, in which* it
was asserted that the plucking the blossoms off potatoes ensured a
greater weight of crop of that oiseful root, and in which the in-
ference was grounded on the theory we have mentioned, though
an' experiment was certainly spoken of. Mr. Findlater, however,
n^t allowing himself to acqniesce in a single analogical inference,
determined to submit the-queetion to the^test of direct e^erimeat,
and this paper contains the result of his proceedings.
New Plan/or constructing Roadt. 87
-On the 19th at July, in the last summer, he selected six drills
of potatoes as equal to each other as could be found, and to a
certain distance plucked off the blossoms of one alternate drill,
leaving the next untouched; and whatever blossoms had subse-
quently arisen on the experimental rows were again carefully re-
moved on the I5th of August, and again at the end of that mouth.
The quantity of ground appropriated to the experiment was the
16'Oth part of a Scotch acre ; and when the crop was dug up on
the 13th of October, and carefully separated, the weight of those
whose blossoms had been plucked was 6 stone 11 pounds Dutch
(117 pounds avoirdupois), and the weight of those left untouched,
6 stone 14 pounds Dutch (120 l-3rd pounds avoirdupois), making
a difference of 3 pounds Dutch (or 3 pounds 5 ounces avqirdupois),
in favour of those left untouched, which is nearly as 38 to 37*
The experiment and the result being thus minutely stated, the
inference to be drawn from it is left to the reader; and as it was
made for the sole purpose of ascertaining the difference upon the
root, no particular attention was paid to the effect upon the stem
or leaves; but there was no difference to attract the notice of a
common observer, except the want of blossom on the rows se-
lected for the experiment.
06servation$,'-^Though nothing is more desirable in agricul^
tural pursuits than to guard against the seductions of analogy, in
general practice, yet ,we cannot but consider this as a sufficient
motive for ascertaining' the existence or non-existence of the
suspected fad by actual experiment. Nor do we think that a
single experiment should be relied on as decisive on the point,
particularly when, as in the present case, the difference . of the
produce on either side is so small as one fortieth part of the
whole.
New Flan for cotisiructifig Roads. By Messrs, Winton and
NisBET, of Edinburgh. '^Farmer^s Magazincy No, 41.
The plan recommended is, " that two courses of stone, each
fifteen inches broad and nine inches deep, in blocks from nine
inches to two, and three or four feet in length as the different
quarries can conveniently afford, be laid along the road level' with
the surface, and at such a distance from each 6ther^ as will suit
the ordinary width of cart and carriage wheels, the stones forming
these wheel ways to be of granite, or any other stone of a suffix
cieritiy hard quality.'' It is contended, that if stones be laid in
this manner, and well secured upon a hard bottom, they will
resist the friction of the heaviest machines with complete effect for
SS Mr. ChtvreuCi chemical Experiments on Brazil and Lffgroood.
klong period of time ; it is, however, necessary that the road shoaW
be kept smooth aud level with good materials.
Qbservatioiu. — ^There certainly are situations in which roads
made in this manner would be f(iund very beneficial ; but we
conceive the expense of securing the bottom oh which the stones
must be laid would more than equal the expense of forming the
best possible road in the usual way.
CHEMISTRY and MINERALOGY.
Ckemicai Experiments on Brazil and Logwood,^ Bi/ Mh. Che vkiu i .
Annates de Chinned voL 66.
Brazil wood or Fernambue (csesalpinia crista) is of different
•hades of yellow and red. Yellow brazil was boiled in distilled'
^aier, the decoction filtred and distilled till only one filth re*
mained. The liquor rhat passed over contained a little acetit
4cid, and some volatile oil resembling that from, pepper in smell
and taste. The residuary liquid deposited, on cooling,' yell^^Vv
flakes, tbe greatest part of which entered into a brown viscous
inass, tasting astringent, bitter, and rather acrid* This mass
being washed with cold water and treated with alkohol at 56^,
was for the most part dissolved, and it formed a yellow solution,
^hich on adding water let fall (lakes, soluble in an excess of hot
water. The solution being heated to drive o& the alkohol, and
then added to a solution of gelatine, precipitated it abundantly;'
alkalies changed it, to violet. The viscous mass also yielded oo
incineration some traces of sulphate of linke.
The supernatent reduced decoction was very deep yellow, acid;
and had a bitter and astringent tdste, which was afterwards very
^arp ; it was covered with an oily iridescent pellicle; it became
red ou adding sulphuric, nitric, or muriatic acid, and deposited'
yellow^ bro\v!i flakes ol colaar and tannin ; it turned violet oft
adding potash, and aminonia was d i:r en gaged ; it threw down
from gelatine coloured flakes formed of animal niatter, tannin,
colour, and perhaps some volatile oil. On being evaporated, it
left a yellow extract inclining to reddish, which on being burned
left carbonate of lime and a little sulphate. Of course the infu-
sion of yellow Fernambue contained, 1, volatile oil ; 2, aeetie
acid ; 3, tannin ; 4, colouring matter ; 5, ammonia ; 6, Tuxic
(both these last probably united with acetic acid) ; Jf ^ trace oit
sulphate of lime, and as it should seem, from their being con*
tained in the extract made for sale, §, sugar, and 9» gttlUeT
oeid.
An infusion of (be wp^ mttde in waur sharpened witb pota
fisib w«9 vt€4etv 9nd let fisilli on adding very dilute sulplHuic acidi
BMiny yellonvish brown flakes, which iv hen washed with hot wa*
ter were neither acid mt alkaline, and wer« a coaibin%ttgn ^o£
tannin and colout'^. with ptrbapa Simi^ volatile oil, although thtf
had not tht tharp taate of it» The supernatant l^or. suU.rt*
tained tiinnin and colour, aS)d yielded .on distiliatipti ti'^aaoiily o£
vinegar. \Vhen the acid had been added ill «xc^a,. the preoipi*
tato contained some of 4t.
Muriate of Hme threw duwiii in the Course vf s^m^ hwii1i,..l[M
purplish precipitate trofn tha infusion i thia precipit^e wp^ m^lH
abundant and deeper coloured when the muriate wai^ pr#vi<H»ljf.
talcined. Il lipprai^d to consifti of tanhiiiy Cotoafi: ai^dUoie.ifih
taining soma okuriatic acid ; '.
- As the tannin could not be separated from the c^^lour hy th^l
above processes, cold water was (ried, in which tbip briusii
wood was macerated for 24 hours. The ^Uered infusion vias: ye)r.
low, and did not coagulate galatine ; but wbeb it was concentraV*^,
^ by evaporation, it b^^aipa bitter and i^^ringent^ and immedi^
Btely coa^lated 'gelatine. That thi( gelajt^ha was not coagulated
at first is {uirtly owiag Iq the quantity of waler^ as a Combination
of taiiniA) c^Jnur and gelatinie. ift more soluble than |be combina^
tinn of only lantitB an^ gelatine, and al^o partly to th^ action of
caloric^ for when the watei" which bad been eVafH>rated aWay was
lidded to the almoat dry residuum, the tiew solution precipitated:
gelatine. The analogous eircuoistances that take place whefi cet^
tain substances that contain tannin are roasted, have bean aecrib-^
ed to the formatiRonof lannin by the rnabting, but it is mbri»
probable that the taniiin is only separated from some combina*
tion which hindered its action upon gelatine.
Alkofaol and ether produce fine yelliiw tinctures containing vo^
Jatile oil, tannin, and colour,, and whiieh are decomposed by
. neater.
As the Colouring matter could not be obtained qliite pufe^ the
cold UEifasion which contain^ colour united with a little tannin^
acetic acidy and volatile oil» and from whence the greatest part of
tlie two latter might be separated by heat waa examined. &ilr
pliuriCy nitric, and mnri«tic acid render the infusion red, and stp«h^
rate red or brewnish >ellow flakes ; the laat are colour united with.
tai^nin, and fall because Uie acid takes away the water that held
tfa^BB 19. aotutioa ; thawed flakei Cental a portion of the acidi anii>
perhaps some Af the oiL Carbonic acid do^ not redd^ft the info*
mk^* Potash^ asupaunia, barytcs, and lime render.ij^ violet, and
unite with the colour and tannin } these cembioationii^ Stre mgrf^
salable • than Uiose formed by the acids* GeSa^inous alnmina
usiiMkwitb the colour, and forms, a /crimson ^e» between tho
piok foj^ned by the acid* M>d th^ ^ifilet of the alkalies.. . O^ide pf
ir«» 23.— TOL. VI. V
90 Mr. ChevreuTt Expmmdih on Brmi and L^gvmd,
lih ad mininvum, (precipitated by ammonia, and washed uintif
that which ii taken up by nitric acid does not precipitate the
solution of silver) forms in a few days a violet lake ; if an excess
of oxide is used, the infusion is rendered colourless. Oxide of
tin ad maximum forms a fine pink lake ; so that one oxide acts
as an acid, the other as an alkali ; and they have the same effect
upon cochineal; and the case is similar when the two muriates
of tin, ad minimum and ad maximum, are used in dyeing. Ox«
ide of iron ad maximum forms a purple lake,- which appears
black when it is dried. The smallest quantity of carbonate of
lime changes the infusion violet red; the in^s'^on also stains
ittarble violet, without causing any effervescence - in these cases
the colour and tannin seems to combine with the carbonate
itself, for the tinge is never so violet i» when lime only is used.
The operation of carbonate' of lime is so strong upoa this infu-
sion, that common paper, and also the blotting sort, changes the
infusion red, and are themselves tlnis* tinged purple, unless the
carbonate is separated by weak nitric acid, and then the infusioir
is not altered when filtered, and the paper is tinged yellow.-
Neutral sulphate of soda, sulphate, muriate, at nitrate of potash
redden the infasion, unless it contains an excess of vinegar, anlt
provided that the saline solutions are concentrated, and added*
in sufl^cient quantity. Salts of Hhie,- magnesia, &e.^ act like'
the alkalies. Acetates of potash; of lime, &c. change the in-
jffision to pink. The oxklic and* tartarous acids, and' ^vinegar,-
only weaken the colour of the infusion, at least if they are not
very strcmg ; they throw down in time a few flakes, scarcely
coloured. Radical vinegar reddens the infusion, but not so' much"
as the mineral acids. Sulphuretted hydrogen gas passed through
the infusion takes away its colour by degrees, and if kept in it-
close vessel it becomes white in a short time, but resumes ita*
yifillow colour if it be heated. Sulphuric acid tntns it red, luid'
alkalies violet, by absorbing the sulphuretted hydrogen and^
uniting with the colour.
To determine whether the sulphuretted hydrogen disoxygenis^d''
the colour or not, htharge (finely powdered, and boiled in water
to expel any air it might retain) was mixed with Che infosion«>
previously saturated with sulphuretted hydrogen gas, and thfe'
vessel was closely stopped: when all the sulphuret was decotn.
posed by the oxide, the liquid again became yellow, and if it vims-^
lefl upon tho oxide for some time, it acquired a reddisbtingft
from the oxide it took up. Hence it appears that sulphuretted *
hydrogen forms a colouiie^s^ combination with the colouiing
matter of brasil. Similar phenomena took place with carbonate
of lead, so that the change was not owing to the bxygen o( JCb« *
litharge. When an Infusion which has been enllvetied by •aa a|i»
isA\ il iMed, 4xA is desnlphiirated by earbonate of lead,* it d#es •
QOk becone of lo detp a yelbw at be£Dre».ms^tbe carbaaiq iin4i
combiaes with the alkali and .colour, ami cendQvsit .paAen. .Lite.
mQ$,(toium*iol) also btcMBts white on bttn§ cianbiaed withlaul-.
pboratied hydrogen* .These cpmhinatioiis jnay? Ue ^preserved • for)
a long time in close vessels. Sulphuretted hydrogen seems tor
Ve the first teriii in the action of acids .upci6 Ui^ infusion. <
. Vauqoelin bas.showa that litmas ifi.ort^naUy red« but isireo«>'
dered bLoe by an. alkali, a:;d that Uie Jeduess produced.by acids;
is owing to their saturatiag the alkali. It litmusipaper is dippedi
iataan infosion of brasil, which contains little or na vuieger, tfaa<
paper becomi^s purple on both sides ; this effect is evideotly pro^i
duped partly by the carbonate of lime in thai paper* To avoid,
which, the paper was dipped into dilute nitric acid, washed, ren«-
dererl blue again by potash, and again washed to separate. the
tmcombined alkali ; and in order to obtain the eolour. iua.sthte
of purity, the precipitate from the alkaline iniiiiion of brazil hy.
sulphuric acid was used; this precipitate was washed with fa
qvantity of water, (which, however, did not ap9>ear an ;triaL to
abstract any sulphuric. acid), in order to get rid o£ the acetic, acid;
that might proceed from tba decomposition of the acetate o£ pot«>
ash formed by tbejuoion of the potash employed y(\\h the .tiaeMi
gar fxistisg.iDthe wood. The washed precipitate beifigitben,
dissolved is water^and depurated litmua paper dipped 'in.the.:s(du«
tion, the paper in about five, minutes, accpiired a xeddish.tiiitt aiid>
the liquid. »be€Jaaie pink by >.coo>biniiig>i)imib 'thcAliosU. unifed
vaik the litsius : iheoce the. colour when united. niiUs t^oniaihaa &
strQii0^r atlraotion for alkalies tban.tbe red.eolouir yA UinitU^ and»
whiekie very retnaikabie, it acts like an aei4« . >' < . : '.
..incision, of braail being evaporated,, yieldst. a yellow eitsact
which had. a reddish cast; like many other ..yellow substanices.
^R^uen itt a condensed state, ^ oxide ofrquicksilvier ad maximum,
or of iron ad Biaximum, minhim, chromaie of lead,. &c») but oii>
ila being redissolved in water it yields ayellow solution as before.
This extract yields on distillation, water containing free acetic
acid» ammonia in small quantity, reddishand, fawpcplour joil,. a
solid purp)]r fat substance that seems to be a combination- of oil
anil.acttkc acid* and charcoal weighing exactly one half .of the
original weight of the extract. . .
♦ . 4
A dry, reddish hrawo, resiidike substance, of a sweet taste
at £rst, but afterwards astiingeat and sharp, has been sold for
9<kme tipoe by the name of extract of brazil wood : it appears
to be produced by evaporating a decoction of the wood.
This extract is not entirely soluble in water. The solution is
brown yeUow>; sulphurie, nitric, or muriatic acid render it rather
paler, and'if more aoid is added, it becomes pink ; it precipitates
gelatine by the taanin it containsy it yields ammonia whea mixed
wUk potesfa^ it alio ^oiitaias oil, awl.ftcti i|i allvccspecl* iil» tKr
MOlvition^oi nu cMcract of bimzilowliioii had been hattolj evapov
nitody: >e](cep$ tbat it .was sweeter; indeed- it cuntaioe sugilr, it^
on adding yeast to tbeeolutioiit and ktUng. ii fenaeiit, aUfiohol.
vas obtained.
The exlvact yielded^ on distillation, waier stigbtly acidulated*
which when Altered was citsine;. had a sweel tatte, pveripitated
kon of'U blue colour, and emittecl ammonia when potash -was
dis^oifedin it; henceiit ivas probably galkte of aoomonlat which
in eertUR circumstances has a saccharine tai^te : along with thia
came some small dr6pt$ of russet and fawn oil, and a pttrple iied
aiibliniate formed of th» oil, the acid, and perhaps sooie f okmr*
ing niat^r. {t left &6 per cent, of very bulky cbavcoa}, which
burned with flame, and left 6^ of yellowish ash, oontainiog ^^ of
parbonate and muriate- of potash, with some traco of sulphate
fuad 4 of carbonate of lime, alumine, red oxide of iron, and
filica, . -
Two parts of nitric acdd at 32^ was poursdupon one of extract ;
maeh nitrous gas was emitted, mixed with prassic aadcArhonic
licids. To diminish the action of the acid, 2 parts of water were
added, and after aom^ time, two more of acid, and the ^aiiUatioii
continued. Wh^q the hquor bucan^e thick,* sosne water vms
added, which threw f}o^n a puinber of flakes that were redistoltred
on applying heat Some sand md stofiea were left behind.
The filtered solution deposited, pn;coo)ing« a<sahttanoe whtek
^oUeoted on the sides of thjs vessel in the form of €attltfowcrB%
^hese fia^es were washed with cold water, afid then disaelittd in
^ot water ; an orange substance (a) being left, pari of whiek
poUected on the surfiue of the sohition and grew solid when thn
jkoiling ceasedi The solotion it^lf depoaite4 by cooking, part of
what it had taken up (kj; that which remained dissolv^ was
of the same nature as the la^t, but it contained more acid
'. The Qimngf spbstaoce, o, hada.slightastringenttaale; it dian
solved ifoicker in nlkohd than, in water, the solution <hd not r«d*
den litmus paper,. U a^Mi yellow, and hnpama slightly turbid oa
cooling. Sulphturicy nitmc, and uiunatic acid, i^thouabt diluted,
l^eripitated it ; >lii;pf water di<(t not render it turbid ; Wttliea ^ct
alkaline carbonates, instead of precipitating it, rendered it clear
if turbid ; these precipitates were, the yeKow substance itself.
The solu^QUipnfecipit^ted ako solution of silver or of tin^ And
nreiale of lead; red sulphaterof iron was thfow& down in retl
flakes, bafr not the aplph^ ad miaimiina, and sohition oi gelaainc-
was immediataly'CoaiEpidkted. Hence this sobstance a is artiiicini
tannin onited with the bitier yelloi^ matter, and perhaps some
nitric acid, lor when it was thmWn upon a red hot iron, it be-
nama carbonised, and afterwards iimehed and took firiei Uke.a
misUarf of nilrc and charcoal.
JMr% Oit^riutM $9f0^mmirm BrmU and tt^gUMul, gs
/ Tbe 8«bstaiice6^fori»ed % white aediment, of a ciiit>o tin^t^ it
tatted somewhat <acuit ^^^ afterwardt astriogcnt- and bUtar.
When it was flang upon iron of a proper heat, it took fire and
ocploded : at; a IM bMt it either burned hke wildfire or it tnelted,
and part of it was soblimed in the form of a yellow powder ; at
a greater heat, it burned with flame like a resin. ^It disaolved inr
nitric acid at 3S^ by heat,- and a part was sepfurated by addiog
water ; the tc^ation, on evaporation, produced a brisk daae aa
soon aa it got dry, and it yielded much prassic ^cid. A solutioa
of this substance in water w>s acid, and precipitated gelatine in
large flakes ; it tlterefore^uiained tannin, and 'also bitter matter
.wbieh cottkl be separated by adding to the h(>l concentrated 8».
luc^n, pure poush ; after this addition, on cooling, small needle-
hke. crystals were deposited, wEkh detonated when heated, and
were of a deeper orange than the •detonating crystals from indigo:
from this detonatiRg property it is probable tfaiat the subeUmce ^
also contains some nitric acid. So that it contains the same
principles aa the orange substance a, but in diflinrettt praportionS|
as the fomaer seems to contain more tannin and lass bitter or
nitric acid than- the second ; but- it is not ualikejy that the
fix«t contains some other principles which were not dtacofvered,
on account of the smallness of the quantity that was operated
upon.'
. Two grains of the detonating crystal^ placed in a small mar-
trass upon hot coals^ gave a report equal to that of a pistol, a
purple flame that extended 2 metres (yards) from ibe matrass*
and a white vapoor, part of which remained in the vessel. On
pouring green sulphate of iron into the veMel, it deposited Prus*
sian blue, ^om the aciioo 4^ the vapour ; and this deposition
was still more abundant if some alkaline water was poured inter
th« matrass, so ^at npt only prussiate of ammonia, but also
prussic acid was formed during the detonation. These detonating
crystals render gelattiie f^urbid, evenaflber they have been crystal*
Used twice, on account of ^beir ^till retain'mg tannin.
The mother water from whefice th^ ciUtltflpwer4ike flakes had
been idep^sitedf was evaporated to dryness, and the residuum
traatad with boilin^^ water. If yielded a yeikw •solution which
Je^, on being j^ltered, oxalate of lime; the filtered liquor contaiu-
e4 bitter, tannin, oxalic acid, and much ammonia ; it also coa.
casaed potash, as appeared on i^eberatipn*
The extract of braaii did not produce in dyeing such bright
eoioars as aa iafuMon of the wood . itself, so that the colouring
nsatter appeared to have been iqored by the evaporation- being
fioo hasty.
I ■♦»■ ii II
f he colouring matter* of logwood app^ra nearly similar
■ys.
V • /
94^ Mr.4^0o^«^^ }afiffSmmt$^tm BnM itid^JLoglDodi:
tib th«t 'of htfaih ftB'ltinds iaiid'alWttli«8 jmMla^e^tlie ftedie effects
upon k, %Qt itictallte siib^Mes produce^ other effects^ the cMfte*'
<if whkh aire iidt v/kAl known. ^. ■ ' . ■
Od 'diitillkig an infofion %>f logwood^ It yielded vviktile oil not>
cmitahihig any acid. The liquor mnaitiing in 'the retort did not-
pedden litmus, but it pKCtpitated ^ekttne. A few,dro]ps of eok
]>b«iric, nitric, or nmriatic acid tunwd-it yel)im,''bnt an excess of*
these acids changed it pink, time and p«^ash -were discovered
in the extract by incinerating it; and ihe.c^xtrac^ yielded vinegar
on being distilled with dilute sulphnvtc acid./ >
If the action of the mtnefal salts, acetates, and vegetable acids
upon the colour of brazil h considered, it is easy to explain the
change of colour produced by roitieral acids in- the red infusion
of brazil or of logwood, for the acid tirstdecompeseA the acctites
contain^ in the wood, and the aceticFi^aieid that is disengaged
renders the infusion yellow ; but on adding more naineral acid, it
acts on the colour and forms a pink combination. The colour
of the wood, whether yellow or red, may also be explained, for
saturated acetates form a red combination with the yellow com-
bination of tannin and coloar ; an<|'weak acetic acid renders the
latter combiilaticm paler than before.. Now the yellow wood haa.
an excess of acid, and may therefore be considered as a combina-
tion of tannin, colour, and acetic acid; but the red wood con-
tains saturated acetatea instead of free acetic acid; and th4^
orange wood, aceii«»acid with more or less neutffil acetate ; > fotf
a neutral acetate pourednntiran infusion of yellows bflisil, which
holds^an excess of acetic acid, changes it red' notwitlistanding
the presence of the acid.
The colour of some very old biiazil was but little soluble io^
water, which arose from the volatile oil being changed into
resin, and thus, combining strongly with the colour, it hindered'
the free action of water, or even of the acida. Hence it is pro.
bable that the colour of red saosders is similar to that (>f brazil,^
and is a combrnation of resin and colouring maitter.
The action of neutral salts, ar those' with a slight excess of
acid upon the colour at. brazil, seems to depend more on the
base than on the acid. Thus if two pieces of stuff are treated,
the one with, common alum, and the other with acetate of alu--
mine,' and then dyed with brazil, nearly tlie same colour will be
produced, notwithstanding aulpharic aeid'fprmsa.puik colour,,
and acetic acid a yellow one with the infusion*
Therais reason to believe that many combinations of colour
and tannin exi^ t in nature, and jthat the yellow colours that pre*
cipitate glue are of this kind ; hence the usefulness of passing?
cloths to be dyed through ba^hs of gelatine, and even oi tannin
'}% evident, for in many cases the eoloat' may not be saturated!
with that principle.
Mr^CkmtuVM txfenoktut$ on Bi^izil and Logwood. 9$
' At sonie.fatikre. timf the application of these exp^imeats to
the opeiatioD* of dyemg wiii be giveo, and tU« causes of the difie*
xences that are observed in the action of the same substances upo&
4»ra£il and k^wdod will he investigated*
. Fresh experiaients have lately- been made to separate the colour
of Bracil fnom the tannin, by means of gelatine. . When acleai
aolatioa of glae is poured into a' yellow infusion 'of brazil^ it it
ciianged .to.viokl red, on aceouat ot' the glue containing some alka-
line salts ; on the «»ther hand, a solution of isinglass renders the
infusion paler, because it contains an acid^ to get rid of which the
isinglass was disf»o)v(Hi in water and precipitated by alkohol,
A yellow iuiuskou oi braail made wildiout heat was then eva?
porated to dryness, to get rid of seme of . the acetous acid it con-t
tailed; the t^xtract was then redissolved in water,, and shook up
akng witli litbaiga to separate the remainder ; the solution being
a|>aiu evaporated: to diyness and treated with alkohol, did not
take up any of th^kad ; it was yellodr withareddiah tinge, arising
Drom some neutral alktdine acetate tha.t it contained. To sepa''ate
this, the solution was mixed with ^ater, and heated ; to drive off
the alkohol 4>urified gelation was then added, and the solution eva*
porated to dryness. On treating this last residuum with alkohol,
a yellow liquor wa9-nb(^ed which did not contain any tannin, so
that the pur^ colour of ^ brazil appears to be yellow. When cloth
was dipped into a solution of the pure colour, it was dyed yellow ;
and if while moisi it was put into, .water acidulated with sulphuric,
nitric, er munaticacid, it became pink ; but if put into an alkaline
water^ it changed to violet.
If -there is only a very minute quantity oi acetate in « yellow
iafusion of brazil along with an excess of acetic acid, the action
of the salt will be very feeble until the acid is taken awi^, and
then the acetate that remains renders the infusion deeper coloured.
For the same reason, a drop of a mineral acid weakens the colour
of the yellow infusion, as it decomposes the acetates of lime, ammo-
nia, and potash that it contains, and the ac'ctie acid added to
that already contained in the. wood, reacts upon the colour, and the
more ao as neutral uiiaeral salts have less action upon the infusion
than vegetable.
On tkeMetais of Potash and Sodi'-^Bf Mess. Gay Lussac and
N TmTtARDJ'^Afm. de Ckim. vol, 66.
...' '••., •">■ •
Dav^t concluded from hi| expanmantS; that alkalies arecompo-
stdof axyi^n and a very inftammaUe metallic substance; but there
are as many reason^ ;to suppose that these metals are comhina-
tienaoi the alkali with hydrogen.
Thtmet^saraohtained by ^vanic procesles in such small quan.L
96 Oh the Meials of P4ftmhmi4 Sodd.
ities that tlie discovery of the method tti procuring it, by €CUtinfi(
he alkali to act upon iron, mutt be regarded at a fortlllMl^ cit
ciimttance. The process has already been given in ths Retrosptct,
vol. iv. p. 465, and therefore it need not be repeated. The metal thus
' obtained may be purified by being paaied through linen under
naphtha, by the aid of heat and compression. It is then pure,
and may be preserved in oil. If charcoal, or any thing which con«i
tains that substance, is employed to obtain the loatal, it retains
some of the charcoal and varies in its properties.
The metal of potash resembles lead, but may be moulded by th«
fingers, and it cuts still more easily than phoephorua. Its specific
gravity is .874. When ilung on water, it takes fire and moves
about slowly on the liquid; towards the end a slight explosion
usually* takes place.
The metal that was produced in an iron tube, in one of these ex*
pehments, augmented its weight %84 grammes (about 59 oz.
Troy), andyiekUdt on water being introduced, 64892 cu)). centim.
(about 5960 cttb« ia*> of hydrogen, at 6^ therm, cent *(4t° Fahr.)
and the baium. at 30 inches J6 centimetres.
This metal combines with many other metals, particularly iron
and quicksilver. On combining with sulphur or phosphorus,
heat and light are disengaged, and when*tl|e compounds are flung^
into water, tbey yield respectively sulphuretted and pbosphuretted
hydrogen.
It burns briskly in oxygen gas, and Is changed into potash.—*
' In common air it changes of a fine blue, and on being shook it
melts, forms a brilliant liquid, and takes fire ; the oxygen of the
air is absorbed and the azute is left. At a high temperature, it
absorbs a large quantity of hydrogen, and forms a whitish grajr
solid mass, from whence the hydjogen may be expelled by quick-
silver or water. At 70* it separates phosphorus, sulphur, or
. arsenic from their combination with hydrogen^ uniting with thenci»
and also absorbing d portion of the hydrogen ; this deeompoaition
is made without fiume even in the case of phoephuretted hydro-
gen. It burns as quickly in nitrous acid gas or oxymuriatic acid
gai as in oxygen, but the flame is sometimes prevented from ap-
pearing by the metal becoming covered with muriate or nitrate c^
potash.
This metal also changes blue, and tak^s fire in nitrons gas, gas-
eous oxide of azote, sulphurous wid gas, carbonic acid i|rtf and
gaseous oxide of carbone procured troip a mixture of carbonate
of barytes with iron. The three last gasses require, however, a
higher temperature to be decomposed; The nkmoegas and gaseous
oxide of asote Uave pureasote; thesulphsrous aeid gat yields'
snlphorat of potash, aad no gastoos residua*) ; the carbonie acid
gas, and gaseous oxide of carboat yttkl' charcoal and potsilfr,
without any gas. It has . np actios^ 9p .fittoric acid gts ilnlaaa
On the Action of Phosphorus, Sfc, on the Alkalies. 97
heated, and then the metal, burns very briskly, absorbs all tbe gas,
and is changed into a blackish substance, which does not HTer-
vesce with water, and which contains fluate of potash, and a little
charcoal contained in the metal.
Many experiments have been made with the metal and ratlriatic
acid gaSy but the gas has not as yet been obtained in a state of
perfect dryness. On treating calomel with phosphorus in order to
obtain the acid in that state, a very limpid colourless liquid was
obtained, which emitted much vapour, and took fire when blotting
p]^)er was moistened with it. This liquid appeared to be a combi*
nation of phosphorus, oxygen, and muriatic acid, and of course an-
alogous to that obtained by treating sulphur with oxymuratic
acid gas.
All the preceding experiments may be explained either by
Davy s hypothesis, or by supposing that the new metal is a hy*
drogurettof potash ; the following requires the Tatter explanation.
Metal of potash heated in dry ammoniacal gas over quicksilver,
is changed into a greenish gray very tusible substance ; the great-
est part of the gas is absorbed, and about 2.3ds of its bulk of
hydrogen is left in its stead. If tbe greenish gray substance is
heated, 2-5 ths of tbe ammoniacal gas that was absorbed are ob-
tained, and the elements of another fifth ; a few drops of water
causes the expulsion of the remaining 2-5ths ; no other gas is se- ^
paratedf and pure potash remains. The ammonia expelled from
the greenish gray substance may be again united with the metal,
and the operation repeated, so that by a given quantity of ammo-
nia there may be obtained more than its bulk of hydrogen, without
any loss of the ammonia. It has been already shewn that the me-
tal does not unite with azote, and if equal quantities of the metal
are treated with water, or ammoniacal gas, ea<ch portion yields an
equal bulk of hydrogen, so that the hydrogen must either come
from the metal, or the \yater contained in the ammoniacal gas, and
as in the latter this ^as must coutain more than its own weight of
water, the hydrogen must come froiii the' metal, which is of course
a combination of potash or of hydrogen.
06«ervflf?o»«.— IVlr, Davy's observations on this theory of the
formation of the metal of potash may be found in our volume
IV. p.'422.
On the action of Phosphorus and Oxymuriatic Acid Gas upon the Alka-
lies.— By Messrs. Bouijllon Lagrange andyoGis.L. — Aj,n, de
Chim, vol. 66.
SoMEyears ago it was observed, that when a.sojution of caustic
potash acted upon phosphorus, it emitted at fi^st.alarge quantity
of phusphuretted hydrogen, andji?ft a blackish residuum ; while the
^as that was disengaged towards tbe end did not tajl^e fire by oiere
HO. 33,—VOL. vu . o i . '
$8 On ihe action of Phosptoruiy S^e. on tkoAtkaliit.
contact of air. The late discoveries respecting the alkalies renJcT
this observation of iniportahce, and it became necessary to repeat
it with care.
The phosphorus was first reduced to powder, by melting it in wa-
' ter, and shaking the vessel till it became solid, which was hastened
by plunging it into cold water. The water being decanted off the
powdered pbospl^orusydiluteoxymuriatic acid was poured upon it to
separate any carbone it might contain, which rendered it white. The
acid Was then separated, and the phosphorus dried by btotting paper.
The purity of the alkali was assayed by lime water, and barytes >
water. Lime water if it has a superfluity of water, is not precipi-
tated by an alkali that contains a little carbonic acid, because the
carbonate of lime is retained in solution, which is not the case
with the carbonate of barytes. It has been long known that caus-
tic potash precipitates lime water, and that the precipitate is
soluble in water; whence it was supposed to be pure or caustic lime,
but it is reatly (inely divided carbonate of lime, which is not taken
Dp because it contains an excess of alkali ; for if carbonic acid gas
be passed through lime water, the precipitate thus formed is solu-
ble in water, although the liquor is neutraT.
The potash was reduced to powder, and an* equal quantity ef
pulverized phosphorus added to it, in a glass mortar placed in a
mixture of snow and common salt to prevent the phosphorus
fro n taking fire. After a slight trituration, the mixture was intro-
duced into a luted stone ware retort, and slowly heated. A portion
of the phosphorus takes fire on account of the air contained in the
vessel ; but this may be avoided by covering the mixture with
some powdered potash.
At the end of the opciration, the inside of the rifttort was covered
with a metallic looking coating like blacklead ; and it contained a
black mass which had a slight alkaline taste; this was but slight-
ly soluble in water, but was all taken up when boiled, except a
black powder. Nitric acid, by boiling, also dissolved it, and left
the same black oxide of carbone^ These solutions contained only
phosphate of potash.
In one experiment, this black mass had no taste, and was not
soluble in water, as it was neutral phosphate of potash : but nitric
acid dissolved it, and separated oxide of'carbotie ; the tube connected
with the vessel was lined with a grayish mass which took fife by
contact with water.
In repeating these experiments, potash and soda were alter-
nately employed, and the gas that was disengaged was neither acid
nor alkaline, but had a slight sniell of garlic. It burned with a
white flame, andyielded on combustion a little phosphoric acid,and
oxide of phosphorus. It detonated when mixed with oxygen
gas and set on fire. It did not take fire on being mixed with air»
oxygen gas, or nitrous gas. It was slightly soluble in water, and
the solution precipitated nitrate of silver of a blackish colour. . It
took fire immediately when mixed with oxy muriatic acid gas, B.nd
then deposited a little oxide of phosphorus ou the bell glass.
Double Refraction of the Cry^aU of Sulphate of Copper, '59*
This gas may bejobtaiued with much ease, by putting some dry
phosphorus into a phial, and sprinkling it with very dry caustic
potash. On heating the phosphorus, white vapours are disengaged
and the gas is emitted. If a little water is added, phosphuretted
hydrogen i« produced as long as any moisture remains, but as soon
as the matter becomes- dry, the forenientioned gas is emitted.
1 he following experiment gives s(»me light on these pheno-
mena: pure potash was ignited by a white heat in a porcelain tube,
and oxymuriatic acid gas was passed over it ; as soon as the gas
touched the potash, agreat deal of water in the form of steam was
produced, which also contained carbonic ocid ; oxymuriatic acid
gas then passed over, and this also precipitated lime water and
h^rytes water : towards the end the passage of oxymuriatic acid
gas ceased, and a mixture of oxygen and carbonic acid gas was
disengaged.
The carbonic acid gas that came over during ihe whole opera-
tion was cloudy, and much too large in quantity to be contained
in the alkali, which had been previously examined, and which, al-
though it could not be entirely frefd from the acid, yet it pro,-
duced only a very slight cloudiness in barytes water. Of course,
hydrogen and carbone appear to exist in the alkali.
A small quantity of muriate of potash is sublimed in this pro*
iCess, which is sometimes of a pale green colour ; the weight of
this muriate is much less than that of the potash employed.
An account will hereafter be given of the phenomena that oc-
cur, when hydrogen an(} oxygen are made to act upon potash.
D6ierra/»*/w .—The^e experiments are very important, as they
seem to shew that the alkalies are combinations of hydrogen and
carbone, which, considering their formation de novo in vegetation,
is more than probable on the first view of the subject.
/
On ihe double Refraction of the CrystaU of Sulphate of Copper. jBfy
Mr, pRiRUil.-— J«it. de Chim. vol. ft*.
The form of the crystals of blue vitriol seemed to indicatte that
they possessed the property of double refraction, but their general
want of a sufficient transparency has hitherto prevented it from
being observed. Crystals, however, have at length been ob-.
tained sufficiently transparent, and these possess this property in
a very manifest manner.
A line joining the two images of a point viewed througn ai
crystal of blue vitriol, is in a direction nearly perpendicular to thA
edges of the prismatic envelope of the crystal.
The slight efflorescence which so soon tarnishes the surface of
these crystals generally prevents the observation of this property*.!.
( 100 )
•k>«*
On the manufaduf'e of Charcoal in close Vessels, and on bringing
into use the various Substances that are produced in the Operation,
By Messrs. Mollerat. — Ann. deChiinie. vol. 66.
Thrke brothers have established at Pellerey, near Nulls, Cote
di'Or, a manufactory on ajarge scale for making charcoal in doser
vessels.
The quantity of charcoal they obtained is double that of the
usual mode, while it requires only one-eighth part of wood tfl be
consumed in the distillation ; it is also better than the comHony
as a given quantity evaporates one- tenth more water than the
other ; hence iron masters may obtain twice as much iron from
the use of a given quantity of wood, and in addition to this there is
also prepar«d a number of other articles, of each of which in
order.
350 Chiliogrammes (700lb) of wood, yield 25 or 30 of tar, ^
which retains so much acid that it is soluble in water; but when
it is washed, and rendered thick by boiling for some time, it offers
more resistance to water. If mixed with one-fifth of rosiu it is
rendered equally fit for the usa of ships, &c. as the common tar.
Four sorts of vinegar are prepared, all of which are perfectly
limpid, which do not, like the common, coi^tain any tartar, malic
acid, resinous or extractive matter, nor indeed any mineral acid,
lime, copper, or other substances. The simple vinegar marks—.
2° hyd. for sails, at 12^ therm, cent, it is stronger tasted than
common vinegar, and produces a , disagreeable irritation. The
aromatic vinegar is prepared with tarragon, the smell is agree-
able, but it has the same fault as the former. The vinoljs vinegar
is formed by addiug some alkohol to simple vinegar ; it has a very
sensible odour of acetic ether ; the alkohol softens the flavour ia.
some degree, but the vinegar is still very sharp.' The acid, called
strong vinegar, is- in feet a very good acetic acid at 10^°*hydr. it
is very white, cl^ar, and sharp, without the usual burnt flavour,
and seems to form the basis of the preceding kinds. It can be
S0I4 for 8 or 9 francs (7«) per lb. which is only half the price of
that distilled from verdigrease. Although not so agreeable to the
taste as common vinegar, these new kinds are more elegant to
the eye, and do not mother.
Carbqnate of soda, perfectly white and transparent, is niade at
this manufactoi^ ; the greatest part of this salt that is used does
not require so much purification, and if the price will allow its
. Ufiing brought into use, 60'per cent of the expense of carriage
* i$ay be saved by drying it thoroughly before it is sent ©ff.
• • The acetate of alumine thai is prepared here is not sufficiently
pure for the use of dyers, asr it contains the sulphates of lime, anU
On Awmi^m NapeUus. ICfl
^f iron, vvhkh last is very prejudicial in dyeing : bnt by using good
alum in its preparation* this iniglit be avoided. This acetate is
also turbid, and contains a white deposit probably of alumine^
which ought to be avoided.
Acetate of soda in well formed, very white, and pure crystals.
It is not of much use, unless physicians should substitute it in
the place of acetate of petash.
Acvtate of copper crystallised in small grains, more brilliant
than. common verdigrease. It is entirely soluble in water, and
much cheaper than that in present use. >
Acetate of barytes perfectly pure ; it would be preferable to
acetdkof limefor preparing acetate of alamine, if it were not too
dear.
Muriate ef alumine is said to be preferable to alum in dying,
but that prepared by Mess. Mollerat is excessively acid, and con*
tains lime and oxide of iron, which renders it useless in many
cases.
Oxide of zinc of a dirty white, and containing oxide of iron,
and a little carbonic acid, which it appears ta have absorbed after
it was calcined.
Carbonate of zinc, rather whiter, but which also contains some
irou, although the carbonicacid hides its colour.
Both the two last substances might be used by painters instead
of white lead.
Besides the above, the proprietors intend to make white lead,
and also sugar of lead.
A cubic metre (yard) of wood yields one hundred litres (quarts)
of acid liquor, besides the above %5 Or 30 chiliogrammes, (50 or
^OM.) of thick oil.
Ohscrfat/'ons.-^The proprietors of this manufactory seem to be
perfectly awaie of all the several productions which could be pre-
pared from the refuse of their principal object ; an'd we have no
doubt but that the substances they procure in this manner will
amply compensate them for the use of the capital that must be
invested in building the furnaces.
The nature of the vessels in which they distil the wood is no|
mentioned, hut they are probably cast irou retorts, or vessels of
a similar nature, in which a distillation per latus takes place. The
application therefore of Lord Dundonald's furnaces for procuring
coke to this purpose would be sull more advantageous.
mmaiL
Qn Jcunitum Ndpellus. By Philip Anthony Stein acum,«—
Joam. de Pkys. Mar^ 1808.
FkisK leaves of cultivated aconitum naoellus, (early blue wolfs
)»ane) treated with water at 45® of temperature, yielded coagu*
\
1 (tt Syrian, Jsclepias^ as a Piant that may he iued instead of Cotton
lated green fecule. The supernatant liquor had a herhaceoui
smell, resembling that of cochlearia whe^ it is'ratber withered,
and which it lo^t entirely on evaporation ; a granular substance
was separated during this operation.
This substance being washed, dried, and exposed to the blow-
pipe did not melt, but became whitish, without either puffing up,
or decrepitating. Another portion effervesced with dilute sul-
phuric acid. ' The liquor yielded soft needle-like acidulous vys-
tals, decomposable by nitrate of lead, and producing a precipitate
reducible by the blowpipe on charcoal, exhaling at that time a
phosphoric smell, accompanied with a slight brilliancy.
The extractive liquor contained a large proportion of mufiate
of ammonia. Aconitum napellus therefore contains green feculse,
a atrong snialling gaseous substance, whicn is supposed to be poi.
sonous, muriate of ammonia, also carbonate and phosphate of lime.
As the neighbouring plants did not contain any phospbale,
aconitum possesses the power of forming phosphorus, or its ele-
ments, and of converting it int* acid.
On Syrian Jsclcpias, as a Plant that may be used instead of Cotton.
By Mr, Sonkini.— Jowrw. de Phys, Mar. 1808.
The interruption of communication with the colonies renders
it of consequence to turn the attention of farmers to those pro-
dvctions which may be reared in Europe, and supply the place
of those now brought from beyond sea. As to cotton, its place
may be supplied by a very hardy plant, the Syrian asclepias,
which unites the production of both hemp and cotton, may be
cultivated on very poor land, and when once it has come to its
full growth, will require no other culture than to keep it clean.
This asclepias is to be first raised by^ sowing the seed ; the
young plants must either be covered with straw, ur leaves in the
winter, or they must be housed : the second year they may be
cultivated by their shoots, which are very abundant. The plants
should be planted out at four feet distance each way.
This plant has been cultivated for some time in Silesia. ' The
day's work of land in Silesia contains|l80 sq. rods, or 18,000 sq,
feet, and holds 4500 plants, each of which yields on an average\
20 pods ; 30 pods yield, after the usual loss is deducted, half an
Quncc of silk, therefore the whole day's work will produce 93 lb,
and 12 half ounces, worth oqe rixdollar. 8 groats per lb. or 500
prench livres (about 21/.) for the whole produce. The gathering
of these pods about the end of October, does not interfere with
tl^e other hurrying times of a farmer's business.
The principal produce of the Syrian asclepias, is the silky down
ty{ the seeds : this down is about an inch, or an inch and quarter
lon^* La Rouviere, in IjG^^ manufactured several article^ fron^
Kesearckes upon tkt Formation of mttatlk Vectridiy. 103
it, particularly flannel, superior to that of England. It has bteii )
said, that these cloths were very liable to cracks, but it is more
likely that , the then inferior price of cotton was the real cause of
the down of asclepias being neglected. The difficulties arising
from the shortness of the down could easily be overcome, now
cotton is so dear. The down is employed in Silesia to make
stockings, and other hosiery. It is also mixed with silk, and
this mixture produces very beautiful stuffs. It is also used there
to make coverlids, to stuff cushions for sophas, as also for beds,
chenille, hats, &c.
When the pods are collected, the stalks are cut down, as close
to the ground as possible ; and then treated as hemp, either in
pits or in the dew ; they yield a very fine white thread. In Ame*
rica these • st^ks are used to make paper, and other articles of
that kind.
From the flowers of asclepias^ the Canadians extract good
brown sugar ; and they are very agreeable to bees. Dr, Barton
has found that they act as a flytrap, and catch the flies that are
attracted by their smell, by means of vaives which are very irri.
table. The young shoots are eaten by the Americans as aspara-
gus y and the leaves are applied to cold tumours.
Observations. — The difficulties that the French find in communi.
eating with their own colonies, in consequence of our naval supe-
riority, has led them to turn their attention to substitute articles
that may be grown in Europe, instead of the traasmarine products.
Although at present the difficulty of introducing new articles into
trade, has occasioned them to proceed but slowly in this career,
yet it cannot be doubted but that the use of these articles will go
oh in a continually accelerated progress, and operate a consider
rable change in the commerce of the world, by reducing it to much
narrower limits than at present, and rendering each of the large
states more independent of foreign commerce than heretofore.
Researches and Conjectures upon the Formation of metallic Elettricityy
or "what is called Gakanism. By B. G. Sage. — Journ, de Phy»
sique, March 1808.
The emperor Napoleon was so struck with Galv^i's experi«
ment when repeated in^his presence, that he not only caused a'gold
medal to be struck in order to commemorate the discovery, but
also proposed a prize of 60,000 franks^ the contention of which
produced such interesting results, that the emperor gave two me-
dals of the value of 3000 franks each, to the authors of these dis-
coveries.
A satisfactory theory of galvanism can only be obtained by
\
154 > On the formation qf MttMic EledrkUy,
employing as few metals as possible to procure it. Zinc, Watef,
air, and silver are the most useful. The galvanic power of cop*
per being unity, that of gold is 1|, of silver 2 ; besides 'silver is
not attacked by pure water, which is an advantage. Round dbci
of metal are preferable to those'having angles.
Lassone has sh?wn that zinc is decomposed by water, and be-
comes covered with a white calx. When filed, it acts upon the
'file like an acid. The calx of zinc when newly made by defiagra,
tion, is strongly phosphorescent^ for more than an. hour. Vitriied
calx of zinc, from the furnaces at Freyberg, yields sparks wb^n
rubbed with a toothpick. Filings of zinc, imoiersed in water,
swell, and emit ah inflammable gas. Wl^en Ktnc i^ filed it is
phosphorescent, but this phosphorescence is still more sensible
in the oxide as already mentioned, which is as strong as the elec-
tric light in an exhausted tube.
When zinc and silver are brought into contact under water, a
part of the zinc, as was conceived by the Prince Primate, is de^
composed, and a caustic calx is produced, whose astringent taste
nearly resemliles that of corrosive sublimate, and the shocks of
which produce still more pain in the joints than those of common
electricity.
The calx of zinc that produces the effects of the galvanic pile
is reduced in the air, and yields electricity and a metalliform
phosphorus. A smell of phosphorus is sensible even in using the
common electric machine.
This caustic metallic calx disengaged from zinc, is very differ-*
ent from the gray calx that is formed at the same time. Mr.
Davy discovered that when the alkalies are placed in the cirrle,
a metalliform and very fusible kmd of phosphorus was obtaioed,
from whence he concluded, that the alkalies are composed of oxy-
gen and a metallic substance ; but it is more probable that tbe
calx of zinc is thus reduced ; and that the acid of the calx renders
the alkali caustic. All metallic calces contain a caustic acid,
besides that which is necessary to tjie calcination of the metal.
This acid and the water causes an effervescence when minium is
reduced by the blowpipe. , .
Another beautiful experiment of Mr. Davy is, the decompo-
sition of salts ^y galvanism, in which the acid previously combined
with the alkali is displaced by' the caustic acid, and is collected at
the positive pole.
It may be said that this formation of caustic acid is a mere
assertion, which may be classed with tlie thousand and one hypo-'
theses of tbe new doctrine, because iron and silver also produce
galvanic effects, although in a much weaker degree Rinnaann has
shewed that it is very difficult to obtain iron perfectly free from
other substances, and perhaps it contains a salt which #S6tsts in
produciNg electric eifects. Ztnc and iroB' b#ing the only metallic
Oh a SyksiancB faund (n tie island of Caprea, lO^
Mtbstancts that yield mftumnabie gas on tolutioBy ^ppwt tooiNF
thii property to a similar principle.
Sigorffne has 'stown io bis Esiunen fumttmi dt h tUmk modernef
just puUashed, that ths thldrjr of thi» comfi^itioo of water it in>*
admiasible, and bats given birtb f(i a saperfetation of hypOflbesi»s»
Tessier's Eitm mw la iMork des ifois 4lm€n$^ publisbed in lt04»
cooturs ill tbe same truth'*
mAMUMbiAi
O^jerro/itfsi.— This paper bears evident marks of tbe.sMiility 0^
the aothar. The aeidum caustitnm of Meyer lids* b^eti' long c6n-
signed to obliviom among sft^st c^mists^ and i^ ii»i likely toM
again taken into favour by anyaitempt of Mr« Sttga t^ briag fl^
once more upon tbe stage.
On a Substance found in iht island of Caprea, j^ Sfr. iLAUQisk*
Ann, de Chitn, vol. LXVI.
' Thts substanee waa first observed by Mr« Briesloek, on €fa«
•ides and at tbe bottom of a ea^ in the island of Caprea^ whieir
is more than an hundred feet deep, and of which the sides i^ra
nearly perpendicular. It is black, shining, in round lumps, or iti
a aUdactilical fM-m, and adheres so much to the rock that it ca»
only be separated by a hammer. Its smell partakes of that of
tan, castor, and cow's dung. It contained stiff hairs of a fallow
brown colour 13 cent, lon^, and small white crystals, of a cooling
tasOe, and wbieb melt upon burning coals like liakpetre. When*
flnng on tbe fire it softened, and burned like fat.
Warm water dissolved more than a half of tbfie substanfce, and
t^ solution lefi„ om evaporaiion, a shavp Mated extntet, of the^
same smi^ as before, which attracted moisture, and whon tdiaced
with sulphuric acid difiused an acid snwll difficult' tor deseribe.
The watery solution of this extrarc was preerpilated. by the ni*
trates of stiver and of barytes, muriate of platina,, and by tiacteni
of nutgalk: no trace of ammonia ' was observable. The dri0i'>
oxuraat yielded <m distHtotioa ad ammdniacal li^uov, fotid' oi^
carbonate of ammonia, and efaansoal coataining m^riarte' of potaMr^.
and potaah itself, arisiing probably from composed nitrate a/ pietrf^
SMh. When disttlled wiOi dihile sOiphvric add, the dried eeetvsKt
3rieldod some water, oil^ end needki-Hke tiystals, wlneh^ oa beirif
resoblmed, were evidotfily eoiia)>oeed of pure benzoic acid, nor'
Uiat tlie attraction this ^tvatt has for t^otstrnw arose faomtiasr.
contain]^ benaOHt of potash.
Tfaer vesidoam, whkb did not dhteolve ifn water, yi<Med to alleeu *
faola-siDMll ^aaotily ol resiiii noe exceeding onei ^ teat of tba*
cNrigtai^ wviglKL The^ reoMikidev i9«a oaly a mixtufo of haira; *
«nall pieces of straw, and some fragments of carbomMof'Mnd-
»o. 23.— TOL. TI. JP
1^ On tnetallisuig Potash and Soda.
md of flinty proceeding probably from the rock to which it acU
hered.
The benzoic acid found in this substance assiinilates it with
the dried urine of h^Tbivorous aninsals, but what animal of this
kind could descend, into this grotto ? . The hairs have the greatest
resemblance to that of the marmot, or they ma^ be those of bats,
which abound in Italy, and may perhaps pass the winter in this
cave. The chemical nature of the urine and dung of bats is un*
known at present.
On account of the resemblance in smell between this substance
and castor, the latter was examined« and found to contain benzoic
acid in about the same proportion.
Observationar^lti a future number of the Annales de Cbemie
are inserted two other papers on this subject, by which we learn
that this substance arises from the snails that creep into the cave
and cannot find their way out, and also froni other small animals
that accidentally get into the cave, and being entrapped, as it were,
perish : but the apthors of the present paper are not thoroughly
satisfied of the truth of this representation.
On a Pfotess by which Potash and Soda may be metdfised vnfhout the
intermedium oflron^ Sf^c, By Mr, Cvkavdav. — Ann, de Chtm^
vol. Lxri.
If, according to the hypothesis. of Mr. Davy« potash and soda
are metallic oxides, it is probable that. the calcinations prepara-
tory to the formation of Prussian blue are nothing but modes of
combining the n^vf metals with charcoal ; and ipdeed.it has been
found that the alkalies may be metallised by heating them strong-
ly with cliarcoal.
\For this purpose either of Uie following two mixtares may be
nied. . Four parts of pulverised .animal charcoal with three of.
calcinedy. but iiot melted, carbonate of soda, the whole .to be mois*. ,
tened with a little linseed oil, or two parts of flour may be mixed
wiUi one of carbonate of soda, and. some linseed oil; in. neither
case, should the oil be in sufficient quantity to form a paste* The.
mnistened powder, is to be introduced into a stone ware or iron,
rttbrt, and the heat gradually augmented until a fine bke jflame'
with,a. greenish border appears in the cavity; to this succeeds a very.
aiiundanl smoke which darkens the. inside of the vetsel» and is in
fact the new metal. The fire cannot now be augmented, for, at
this (Murticularte^nperature .the retort begjins to melt: the iron re-
torts resittrtbfi fire the longest as ithe ajkidi does not act ^upon;
them Jo.miKfa as apon eattbeni and the hfat also passes through .
thw easier.
Experinunis m Indigo and Wtmdl 107
On- account of this d<^licacy in the operation, three penont are'
required to perforin it. One introduces a cold- rod of bright iron
into the hollow part of the vessel, which becomes covered with
metalloid, and almpst immediately withdraws it and plunges it
into oil of turpentine kept-co(4 by standing in a tub of water. The
second blows the /ire and maintains it at an equal height. The
third collects the metalloid from the n)d8, plunges them in water'
to cool \hem and separate the alkali that might be formed, and
cleaus them in order that thB iirst may have them ready for hie
use.
The production of this metal does not arise from the disox-'
genisement of the alkali, but it is a new combination^ in which
hydrogen is coniamed in a very condensed state.
During the operation hydrogen and non- metallised alkali are
volulilised, as also a large quantity of prussic radrcai gas. So
that either hydrogen is a constituent]iegi)edient of the alkaliee
whi^h is disposed to separate by mean^ of the charcoal, or else'
charcoal contains hydrogen.
Observations.'^n this paper, as in all other continental ess^s,
the metalloids from the alkalies are considered as hydroguretn; •
and not vyitlio^^ some reason, wbcui we reflect on the 9niail spe.:
cific gravity they possess. The experiments on ammonia and.
quicksilver hav.e shewn how a very small quantity of rasttei^ iB
capable of altering the properties, of. the substance to which it ia:
added ; and the presence of water, to afford a. sufficient quanti^;
of hydrogen is evident from the experiments that have been' re.
cently made on potash apparently dry. Davy's own experiments
on muriatic acid also shew in what a latent state a large propor*
tion of water may be concealed; and we apprehend that the do.
cimastic experiments of that chemist were not made on a scale*
sufficiently large to afford accumte results, . . - «
jaa^
Ckemcal Experiments on Indigo and Wood, By Mr. Chevreul.
Ann, de Chim, vol. LXVL
An abstract of the first part of this paper, which treats of in*
digo has been already giyen in the last volume of the Retrospect,]
p. 12399 from the Journal de Phvsique. The second part treate
chiefly of woad, and of this an abstract is now presented to pw:
readers.
Woad hasia very sensible smell of tobacco, and whe^ the liMPope
are broke, they are found to contain fragments of leaves* wo<Miy
and sand. When distilled it yielded a watery liquid that reddened
litmus, also sulphur dissolved in an oil, carbonate of ammonia,
come traces of prussiatei yellow oil, smelling l^e distilled .§ni|i[ial
wvk&UtuMg^nsid ivbich became brown and'cencr^U by the air; |^
bulky coal kvhicii 3?ielded alkaline ash«s, and gasses. " Hie tracef
of prussiate were dt&covered by a paper impregnated with sulphate
of ire^n ad minimum, whicb, being soaked in t)ie liquor, e^rveseed
^kb dilute sulpburic acid, and was ebanged purple in spots.
Twenty grapcunes (twp tbirds of an ounce) of voad being dis-
tilled wMb four decilitres (a pint) of water^ yielded a scented
water neitber acid nor alkaline, but containing some sulphur,
which was probably dissolved by a ' volatile oi^ for when oxy-^
muriatic acid was added to this water it precipitated nitrate of
1>U7tts. The water ^id not blacken metallic solutions, but paper,
impregnated with carbonate of lead, became black on being sus«
pendedoverit*
The woad remaining after this distillation was exhausted by
means of repeated additioiis of fresh water \ the first washings
were reddish, the second yellowish : it was reduced by thb means
to 13*2 gramm(^8.
The first washings, being diluted with sulphuric acid, yielded
acetic acid and muriatic acid ; distilled with potash it yielded
i^mnonia. It reddened litmusi and sulphate of lime was found in
it; by using nitrate of batytes and oxalate of ammonia, nitrate of
^ver threw down a precipitate partly solnUe in nitric acid.
Ammonia only deepened the colour ; muriate of tin and acetate
of lead. separated colouring extractive matter. Acid sulphate of
ison also deepened the colour. Nut-galls separated flakes of ve-
gsto-^ttiimsil matter. '
The remainder of the washings was evaporated, brownish pel-
licle* were deposited, and other flakes remained suspended. It
was then filtered and again evaporated, and afterwards mixed witl^
alkohol^ Tbe alkoholic solution had a sweetish and slightly
bilter taste ; it became covered with pellicles oi extractive mat-
ter^ on exposure to the air, and yielded some crystals of nitrate of
potash.
The woad that had been washed with water was treated with
boijiog alkofaol. The first washings w^e deep green, and depo-
sited, oh cooling, flakes of that wax which accompanies the green
fecula of vegetables, and which has been found in many barks,
particularly that of the cherry; \Afler this, the liquor being fil*.
tered and evaporated, deposited a blue fecula, which was evident-
ly indigo : the reniain 1x4; liquid retained a portion of thij$ adong
with some green feculu' ' The second washing w£is not so green*.
but rather blue. When concentrated in a retort, they deposited
siiu^ purple scales of indigo j the supei4)£^tent liquor beiAg filter-
ed and evaporated, deposited, when slowly cooled, smsdl white
grains adhering tt> the bottom of the retort, and fl,ake8 of tbe
same substance were suspendjpd in the reniaiuing liquid* Thia
wlnle matter became blue by contact of airi aud'even under the
fiquid if it were exposed to the sun, so tbat this singalw tnhu
stance was probably indigo at a niinimiim of dxidiisenieiit*
It required a considerable quantity of alkohol to exhaust the
yoad, which was reduced by this means to il grammes, and
which were only woody fibres mixed with sand.
Hence we may conclude that woad yielded to water, '54 per
cent, composed of sulphur, acetous acid, extractive matter, gum«
vegeto-animal matter, sQlp^iate of lime, iron, nitrate of potash,
muriate of potash, and the acetates of potash, lime and ammonia;
ito alkohol, 1 1 per cent, composed of wax, indigo ad maximum
and ad minimum, and green fecula ; the remaining 55 per cent
being woody fibres and sand.
The iiidigo in woad is probably contained in the plant, for the
preparation of this dye stufi^ is not likely to have pitiduced it, but
only to- have oxygenised that contained in the plant, and to have
jkrmed the acetic acid and ammonia. But to avoid all doubts,
the plant merely dried was examined. When treated with water,
it did hot yield any nitre, and it yielded more muriate of potash
than ther prepared woad balls : the free volatile alkali Uiat it
Contained restored the blue colour to litmus that had been pre*
viously reddei^ed by an acid. In other respects it yielded the
same as woad balls. The plant which had been exhausted by
water yielded wax, indigo ad maximum, and green fecula to alko-
hoi. So that indigo exists ready formed in the phuit, and the
case is evidently the same in the indigofera, in which however it
IS at the minimum of oxidizement.
By the observations of LechenauU it appears that at Java,
they make a kind of indigo which is superior to that formed in
the usual nnauner by fermentation. The plant is washed to
separate the dirt, and then boiled in copper pots containing about
7 or 8 quarts of water, until the water acquires a green colour.
The water is then poure^d into earthen jars holding about 80
or 90 quarts, ^nd beat up until the scum appears blueish ; the
fecVila is then peripitted to subside and afterwards dried.
Indigo certainly exists m many plants, although it has not
hitherto been noticed, because its characters have not been suffi-
ciently laid down. It may be discovered by leaving the expres*
sed juice of a plant exposed to the air for some days, and then
evaporating it ; the indigo will be separated as a blue or green
powder, which will yield a purple smoke when placed on' a hot
iron. It may also be dissolved in sulphuric acid, with which
indigo forms a permanent blue solution.
If the indigo is mixed with green fecula as in wnad, the plant
must be exhausted by water, and then treated with boiling alko-
hoL The first solutions contain much of the fecufa, but the
succeeding ones, which are blueish, contain more of the indigp.
110 On the relation betweefi the oxidation ofMetali^
ii thes^ solutions ai^e evaporiited a^lmost to dryness^ and alkohol
again added, it will take up the fecula and leave the indigo;
Indigo ought to be looked for in galega officinalis, (goat's rue)
from whence Linnaeus says a fine blue colour is extracted; and
in scabiosa succisa, (Devil's bit) from whence the Swedes pre-
pare a blue fecula by treating it in the manner of woad. The
plants which yield permanent green colours probably contain,
besides indigo, a yellow colouring matter.
Observatiotis. — In addition to the tuperiar quality of indigo
which is prepared by boiling, Mr. Chevreul might have added,
that this process is free from the unwholc^some efHuvia whicl)<
have been partly the occasion of the culture of indigo having
been given *«p in the British West Indian colonies, as we are in-
formed by Edwards, in his history of those colonies, as tlie va-
pours arising from the putrescent vats in the old method produced
a great moitality among the negro .workmen employed in the
manufacture ; the colouring matter is oxygenised in this process;
by the continual agitation given to the liquid, instead of waiting
ibr the absorption of the oxygen from the atmosphere whilst the
liquor remains in a state of repose, and thus infects the air with
its putrid efHuvia.
X
4. ^
On the relation that exists hetweai the Oxidation of Metals and
their capacity of Saturation for Adds, By M. Gay Lussac,— •
Mem. d'Avreueil, vol, II.
The object that M« Ga[y Lussac purposes to pursue in this
memoir, is the demonstration of a principle, that the quantity
of acid in metallic salts is directly proportionable to the quantity
of oxygen in their oxides. The results of analysis are not
sufficiently exact to be employed. The evidences are derived
from the precipitation of one metal by another.
When acetate of lead is precipitated by a plate of zinc, the
metal is thi^own down in its metallic state ; little or no gas is
produced, and the solution suffers no change as to its neutral
state. Hence it follows that the 2inc Saturates all the acid of
the solution when it is combined with all the oxygen of the
oxide.
Similar phenomena are observed if sulphate of copper is preci*
pitated by iron, or acetate of copper bylead, or zinc, or if copper
precipitates uitrat of mercury, cobalt, or silver. In iall these
cases the oxygen and acid of the metallic salt precipitated pass
into thie metal, occasioning the precipitation. Of course the
Quantity of oxygen in the sailt formed, is th^ sdme as was in that
and their capacity of duration for Adds. ' 111
d^ecomposed, and the proportion of metal it contains is inversely
as the affinity of precipitating metal lor oxygen.
Some instances occur which present different results. Thus
the action of zinc on muriate of antimony is attended with the
evolution of Iiydnigen, becaase this Salt, to remain in solution,
requires great excess of acid; and muriate of zinc dissolves when
nearly in the neutral state.
It is possible that a salt formed by the precipitation of one
that is neuti'al may possess an excess of acid ; in this case, oxide
is mixed with the precipitated metal.
Lastly, the precipitating metal may decompose the acid of the
salt, and produce a complicated effect. Zinc has this effect on
nitrate of copper, it throws down the copper, partly in its metallic
fetate,, and partly in ihe state of oxide. But these particular
instances do mot oppose the general principle.
There is every reason lo believe that metals at the maximum^
like those already considered, and at what Proust calls the mini,
mum of oxidation, have their capacity of saturation propor*
tionable to the oxygen that in tliis state they contain. Only a few
facts can be brought forward in support of this generalisation^
because highly oxidated metals form salts of difficult solubility.
Mercury converts corrosive sublimate into calomel, and white muri*
ate of copper is changed by exposure to the air into green muriate,
and an oxide containing a litile acid, convincing proofs that per*
oxides require more acid than proloxides. Mild mercury is f(»rm*
ed by the .repeated distillation of mercury and corrosive sublimate
without the .emission of either acid or oxygen. Hence it is evi*
dent that the acid in both salts is proportionable to the oxygen
in each oxide ; the analyses of Mess. Fourcroy and Thenard con-
firm this, and the analysis of the muriates of copper by Proust
and Chenevix lead to a similar conclusion.
The principle that the acid of a salt is proportionable to the
oxygen of the oxide is of great importance, as it affords an easy
method of ascertaining the proportions of metallic salts, which
in general are very uncertain. The only data necessary are, the
proportion ^ oxygen, combined with the metal of each salt, and
the^composition of ojoe salt of each genus. • Tht muriates will
afford an instance. Muriate of silver contains, silver 100*00:
oxygen, 7*60; acid, 25*73 ; and J 00 of lead require, according
to M. Berthier, 7*39 of oxygen ; the proportions therefore of mu-
riate of lead, according to calculation, are 100*00 lead, 7 '^9 ^^y*
g^n, 24*68 acid* The proportioii of acid, according to Mr. Kir*
wan'a experiment) is 24'Q3. t «Agaii» 100 of mercury at the m«3(r
imum is combiiied with S*21 .p£;oas»ygen; from calculatioa it
should unite, in corro/si^ie. sublimate > with S8:l6. of^acid;. ^M
from .the^ e^pf rimeiAjts of : Tbennrd a^d^Fourcroy, this 8alt'€0|i«'
tains. 27*39 of acid.
112 On the retoHon between the oxydation qfMetdU^
It is curious, that tbougb the acid of the salt is proportionable
to the oxygen of the oxide^ the proporcion of oxide bears no rela*
tion to the oxygen of the acid : for when sulphite of lead is eon-
irerted into a sulphat, the oxide is,'te before, just Ruflicient to sa*
turate the whole of the acid ; on this circumstance, and on the
fact that sulphuric acid may be converted into two parts in vo«
lume of sulphurous gas and one of oxygen gas, the calculation
for ascertaining the composition of the sulphites principally de»
pend. The affinity therefore of sulphureous acid is to that of
sulphuric acid, as the weight of two parts of sulphurous gas,
plus one of oxygen, is to the weight of two parts of sulphurous
gas. Hence sulphit of lead appears to be composed of 100*00
lead, 7'29 oxygen, 30*30 acid.
The proportion of oxygen in metallic oxides is as easily ascer**
tained as the proportion of acid in salts. It is only requisite to
know the quai^tity of acid in each salt, and the composition of
one salt in each genus to find out the* quantity (of oxygen in all
oxides. For inUanee, sulphate of lead, from the analysis of M.
Berthier, is composed of 100-00 lead, 7*29 oxygeii, 3771 acid;
and sulphate of barytes, according to the same chemist, is com«
posed of 66*5 barytes, 33*5 acid ; therefore 100 of the metal of
barytes require 10*77 of oxygen.
Lead, silver, and mercory, at the minimum, contain very little
oxygen, and they form with most acids insoluble and neutral
salts. This insolubility results from the general law, that a
compound which possesses much of .an insoluble principle, is
more insoluble than one which contains less. O^^muriate of mer*
cury is very soluble. If the oxides of all metals were very soluble,
the salts that they might form would be perfectly neutral. For
the excess of acid which occurs in some salts is foreign to their
Saturation : it is only pecessary to prevent the precipitation of
the oxide by destroying its force of«cohesion.
In the precipitation of metallic solutions by sulphuretted hy*
dfogen, either alone or combined with an alkaline base, *tbe
hydrogen combines with the oxygen of the oxide, and the sulphur
with the metal ; therefore there should be as many metallic suly
"pbureta aa there are metallic oxides ; but at the latter are fixed*
the varietiea of the fbniier should likewise be determinate.
OAfervo/UHii.— The remarks of Mr. Oay-Laissac on the precil-
pitation of one meld by aiiothtr, ai^ new and inteneetiiigy and
we conceive that they fally pr«ve the truth of the prmeifxie
whieh he endeavours to eetabiith: in respect to sevttral sdits ; bfit
they affiipd no evidencea that it is a general law, eqCMdly appltea*
Me in all eases. A great exesption to it appears in the ssb and
soper acid sails ; M\tam can tha qaantity of acid in a metalHe
salt be proportional to the Qxygen in the oxide, when the same
r
, and their capaciftffor the saturation of Acids, 113
bxide is capable of combining with different quantities of acid*
6ome of these sub and super acid salts are so dtbtihct in tbeir
properties and well defined iu their formation, as not to admit
of being considered as mer6 mixtures of the neutral salt \«rith ah
"Excess of acid or base.
NVhether the principle be Original or not, is another cot^Mdera-
tion. 'Judging from appearances wie should be inclined to deter*
mine in the negative, but we are unwilling to make the accusa.
tiou of plagiarism ; this is certain, that the priority of discovery
belongs to Mr. Diilton, who, in his Elements of chemical Philo«
6ophy, referred to by Gay-Lussac before this niemoir was pub*
lished, has applied the converse principle, viz. that,thei quantity
bi oxygen in an oxide is proportionable i^o the acid in the-sblt,
to calculate the proportions of oxygen in potash and soda. And
that the principle is deducible from Mr. Dalton's general hypo-
thesis concerning combination in definite proportidns ft evident
pn the slightest consideration. This gentleman infers,' that a salt
which contains a metal at the minimum of oxydation is (to use
his expression) -a binary coriipound of one atom of oxide and ode
of acid ; now asit is well known that metals at the maximum of
oxydation require more acid than when at the minimiipi, it fol-
lows, of course that sa]td in which the metal is in the former
state, must be ternary compounds of one atom of oxide and two
atoms of adid. M. .Dalton's hypothesis has the advantage over
that of Mr. Gay-Lu«sac> it admits of one atom of a body con»-
hining with one, two, thre*, or more atoms ^f another bo4y for
ivhich it has an afiinity. The merit of Mr. Gay-Lussac consists
|>rincipally in advancing a part of Mr. Dalton's hyt)otbe$i8, in a
more intelligible form, ilinstrating -it by a variety of instances,
and pointing out its application to the determination, of tJie pro*
portions of metallic sal tfc4 One v^ry curious fact is mentioned
in this memoir j which deserves particular attention as connected
with the important and recondite subject of chemical affinity.
We refer to the conversion of sulphit of lead intb a sulphat, with-
out riny changv^ of the saturating power of th6 acid being pro^
diiced. li is evident from this that the additional portion of
oxygen does not a<fect the original affinities which united the
oxide of lead and sulphureous acid. We have no doubt, if there
t^rere accnrate data for calculation^ but that ^Iphuret of lead
would be found to have the same relation to the sulphit'aa the
SuTphit had to the sulphat ; that is to say, that lead is combined
With the same quantity of sulphur in the sulph\iret, sulpKit, and
sulphat.
The truth 6f ihe hypothesis employed by Mr. Gay-Lussac to
explain the insolubility of s*alts wtf shall venture to call iti ques*
tiori, notwithstanding the high authority of Bertbollet, who fir^
NO. 23. — VOL. Vl. Q
k-
114 * Anafytis of a Uatk jiandL
advanced itr The facts in opposition to it are as many noa^lf
as those in its favour, arid ibey ati'ord objections that cannot be
remoived. In salts, for instance, at tlie luaxiraum of oxydation«
the attraction of cohesion, as Mr. Gay-Lussac reonarks, is sq^
powerful as to require an excess of acid to keep them in solutioi^
whilst the salts of the same metals Itiss oxidated are easily solu*
ble. But the contrary should be expected from the hypothesis,
as the proportion vi the soluble el^qi'ent is much suialler in thip
latter case tha^ in the former. To take particular instances ;
thi" insolubility of sulpbat of b^irytes is not to be compared wit^
that of 6u\ph4t of silver, yet, according to Mr. Gay^-Lussac's cal-
culation, s^lp^at of barytes contains most oxygen and acid ; oii
the contr^y, muriat of barytes is very soluble, and nmriat of
silver quite insoluble — facts ^Uogetber inco^ipatible with the
prin^pfe that a compound vy^ich possesses (tnich of an insoluble
elem^iiit is more insoluble than on^ which contains less,
ii J ■■■-■■*
^ "p^p w m
=*-p*r-
Ckcpticat atialym of a hlaek San^yfrom the River Dec in Aberdeen'
sJ^ire^ 0d of a C^P^f" 0)re jroin Arthrey ik Sferlingihire,
By Thomas Tl^0^I^»ON, A/. Z)., Lectvrer on Chemistry, Edin.
burgh.^Trans. Edtd. Sec. Vo{. VL Farf IL
The black satid, independent of the quarts felspar and mica with
. which it it xnhced, consists of two kinds, one of-'whiclli i^ called
iron sand by Dr. Thompson, and th(e other iserine, ; the iron' sand
does not exceed one-fourth of the mixture ; it Is disiin^uished
from iserine by being strongly attracted by the magnet j^ tts spe^*
cific gravity is 4*766, and that of iserine 4*49 1, or;fr^ from ex*
traneous matters, 4*964. Du G. obtained from 100 graius of
iron sand ^ . . . i <
-of black oxide of iron , . .
white oxide of titanium .
arsenic • - • • •
^ilica an4 alumina « «• f
9S70 grs,
12-65
1*©0
1*50
Total ii3-85
The increase in weight is a^ttrihuted to an absorption of ojcyge^^
by the products. Dr. G. conclu^e^ from his experimeiits that
ircin in most of its ores is comhiped, with between ij i^nd l^P^
cent, of pxygen ; this combination he considers as the real pf oloxr
ide of iron ; he presumes too from analagyi that there is a fifth
oxide intermediate between tbt green demonstrate^ by I'henardi
und the red*
I
(
AnaLfsis of a biack Sand, 115
I)r. G. having found that white oxide of titanium loses | of iu
weig)it by its conversion into red oxide, and that red oxide wheh
raised to the state of white oxide increases exactly one^third^of
^ts weight, is disposed by these 'facts conjointly with th^ exc^|i«
tion of Vauquelin and Hechl to consider the three known oxides
as composed of the following proportions of metal MA oxygen.
Metal. Oxygen.
1. Blue. 100 16
2. Red 100 35
3. White 100 49
On the suppoMtion th^t the titanium is in the state of red ox.
tde and that th^ arsenic and s ilex and alumina detected are fo-
reign to the cothpositidn of the iron sand, Dr. G. infers that thfs
pre is composed of 9 p^fts of prcrioxide of iroa and one of red 03d«
ide of titanium*
' )00 grains of iserine afforded by analysis,
of o.\ide of titanium' • • « 54*8
oxide of irwii - - - - 46*0
oxide of uranium , . - • 4*2
silica - - T - - l6*^
alumina - *^ • * • 3*2
Total 125-
Pr. Tfion^son reduces ^bc weight of the products, to nearly that
pf the original quantity, on the idea that the one is only composej^
of protoxides. Excluding silica and alumina, he concludes that 10^
parts of iserine contain nearly 48 tichanium, 48 iron, 4 uranium*
The ore of copper which Dr. T. examined was a species of
grey sOlphuret that readily tarnishes on exposure to the atmos-
phere ; from his analysis he considers its composition as folloy^s :
iton, 51'0Vcopper, 19*2; arsenic, ^5 7 ; sulphur, 14*1.
From the appearance of the ore he conceives it to be a mix-
tiire of sulphuret of popper and arsenic pyrites.
O^ervationSn'^Tht arguments which Dn Thompson employs toi
prove the existence of a new oxide of iron, are certainly demon*
strative, if the results of his analysis areallowed to be accural^.
But their accuracy is doubtfiil, from several sources of error which
his methods exhibit. For instance, we find that the iron sand
was heated to redness for two hours in a porcelain cru^rible with
twice it's weight of carbonat of potash, is it not probable thei^
that the silex and alumine which appear amongst the products,
ix6 Analysis of a hhitk Sand.
were separated from thecrucible, and not derived from tLe mineral F .
•—The strong action ot'carbonat of potash upon crucibles of this •
de^erijltion is too well known to need any comment. Again, we
perceive that Dr. G. added ammonia to the muriatic solution, to
throw down the oxide of iron, before he had precipitated any alu-
mine that might be present j and that he neglected to digest the
precipitate in caustic potash. May not the increase of weight be
attributed to alumine, either derived from the crucible or mineral^
and thrown down mixed with the oxide of iron by ammonia ?
Volatile alkali is commonly employed to obtain alumine in its
pure State, and it id rather strange that Dr. G. did not take in this
instance t)<e same precautions in estimating the propottioh of
iron, as he adopted in the Succeeding analysis of isehne* Beeides
these cfbjections to Dr. Thompson's conclusion, it might perhaps
be expected that the iron after being J:reated with alkali wt>uld
afford hydrogen during its solution in muriatic acid^ if it existed
in the mineral in a state of oxidaticm inferior to that of th^ black
oxide precipitated by aiUmonia. But on this we lay little stress,
as the iron niay he said to be converted from the proloxide into
theblaffk oxide, during the operation by the decomposition of the
water that the alkali may be supposed to contain. The numbers
that Dr. G. has given in estimating the proportion of oxygen in
the different 6xides of t'tanium, perfectly agree with Mr. Dalton's
very ingenious hypothesis, concerning definite* proportions and
fcorabinatiotis by multiples. Dr. G. must, we conceive, have had
this hypothesis in view, for without it's assistance we db not un-
derstand how these numbers could be obtained froiii the experi-
ments which he mentions. The estimations in their present stattf
can be of little Service until established by accurate experiments;
Though in tlic analysis of iscrine we cannot perceive any new
cause of error, yet we are inclined to attribute the great increase
of weight in part to alumine and silex, separated from the cruci--
ble ; a new oxide of iron is not t6 be admitted without good evi-
dence of its existence. We hope Dr. Thomson will repeat the:
analysis, for though we may doubt his first results, it \Vbuld b€
difHcult for Us to refuse our assent to the second experiments of
o excellent a chemist.
No. XXIV. uil! be published Augiisi 1, 1810^.
JtETBOSP'ECT
OF
PHILOSOPHICAL; MECHANICAL^
CHEMICAL AND AGRICULTURAL
DISCOVERIES.
■SB
■■^— — ■»
No. XXIV.]
Aprily Mai/, June,
Lisio.
KAT15RAL PHILOSOPHY, ARTS, ani> MANUFACTURES;
()n the Volcanoes ef JoruUo. Etf Alexander Humboldt.-^
Joum.de Phys, vol, LXIX.
XHE account of these volcatioes, extracted from Mr. Hutn.
boldt's Essay on New Spain, relates to <me of the inogt es^teiisive
physical changes that the geological records of our globe exhibit.
In 17^99 ^ mountain of scorias and asb«s, 517 metres (563
yitrds) above the old level of the neighbouring plains, waii
Suddenly formed amidst a great number of burning cones, at
the distance of thirty six leagues from the sea shore, and
forty-two leagCicfi from any other volcano. The ' plain^ ok
which this took place, lies between the hills of Aguasarco shd
the Pacific Ocean, and is elevated from 750 to 800 met.
(from 8^0' to SSO yards) above the level of the sea. The strnu
tnits of the adjaceht basaltic hills are crowned with ever-green
(oaks, wbicTi, intermixed with thei foliage of laurels, olives, and
dwarf fan palms, afford a singular contrast with the arid plain,
^hicU has be*h laid waste by the violence of volcanic fires. Ih
the month of June, 17^9) the inh^bUants were thrown into the
greatest consternation by a fearful rumbling noise, accompanied
by frequetit shocks of an earthquake, which succeeded each pther
at intervals for the space of fifty or sixty days ; after which they
Entirely ceased. On the 5Sth of the following September a ter-
tible subterranean noise wa"^ heard, and the frightened Indians
fled for safbty to the mountains of Aguasarco. , A space of three er
fi>ot square miles was floated in the form of a bladder, the bouo*
No. 24.^^ vox. VI. ft
J is Mr, Humboldt on the Volcanoes of JorutU,
daries ci which are still visible by the ruptured strata, aild^ ^
about 13 yards above the level of the surrounding t>lai!i, while
toward the summit it gradually increases to the height of l6(X
met. or 175 yards. They who witnessed the awful scene from
the top of Aguasarco, assert, that flames issued from the earth
for the space of more than half a square league^ accompanied
with fragments of red hot rocks, and clouds of ashes, resembling
a stormy sea. The crust of th^ earth was seen to s#eH, and the
two small rivers of Cuitimba aud San Pedro were precipitated
into the burning crevices. The decomposition of the water reani-
mated the flames, which were visible at the city of Pascuoso, si-
tuated on a wide plain 1400 metres above the level of JoruUo.
A great number of small cones only two or three yards high were
raised on the dome of the larger elevation, which the Indians call
•vens.' The beat of these had greatly dinMnished, according \»
the testimony of the Indjians^ when Mr. II. visited them; but many
of the crevices emitted ah aqueous vapou** ; and in these the
thermometer rose to the height of 95^ (if cent. 203° F.) Each
^cone is a chimney from which a volume of smoke issues ; and in
•several a subterranean noise was heard, like that of a boiling \u
quid at no great depth. Though the 'fire appeared to have lost
much of its activity, and the volcano and surrounding parts were
hegiuning to be covered with vegetables, Mr. H. found the heat
of the air very consideraible, as the thermometer in the shade and
much above the ground, ro^e to 43^ or 109'4* of Fahrenheit.
The two small rivers which were lost, are supposed to break out
iigain in two springs from the clayey dome of the furnaces ; the
therawl waters of which, possess a temperature of 126* SG^ of
Fahr. The situation of the new volcano af Jorullo, gives rise to
a curious geological observation ; that the line of volcanic moun-
tains in Mexico does not coincide with,* bat is perpendicular \o the
axis of' the great chain of mountains in that country. This new
volcano was formed in a continuation of this line, which is com-
prised in a narrow zone, included between IS^ 59^ and 19^ 12^ of
oorth latitude. Mr. Humboldt's observations on this chain of vol*
canic mountains induce him to conclude thai there exists a fissure
At a great depth below the surface of the eaith, extending from east
to west, through the space of 1^7 leagues^ from which the voica*
nic fire has made its way at different times, bursting the outer
, crust of porphyritic rocks, fronpi the coasts of the Mexican g^lf
to the shores of the Pacific Ocean.-
-T
Obiermlknu^'^lht object of geology is to unfold the structure
of the globe, to discover by what causes its various parts have
been arranged ; to ascertain, the source from which the immense
number of different substances of which it is composed have eri*
^inated 9tnd their general stratification, and the inequalities which
Mr. Humboldt on the Volcanoes tifJorullo. 1 19
■xfiversify its surface have arisen. In the pursuit of this investi-
gation, however, many diflkulties occur. The mere crusl of the
earth is all to which our knowledge of hts materials can possibly
extend ; a small portion of this only is inhabitable, and a
much smalllcr still in a state of civilization ; our experience
i« therefore very limited. Numerous facts, however, have been
collected that most tJecisi-vcly prove tbat the general mass has
undergone various wvolutioTis, tind that these have not only been
of gieat antiquity, but of universal extent. There is ample proof
that its whole surface has been covered with the ocean, and that
e^•ery part of it has suffered a change ; mountains have been
raised, islands separated from the main land, and the waters col-
lected so as 10 leave the elevated parts dry. It is difficult to
cx)nceive canses adequate to the production of such effects ; and
opco-ations so immense seem far removed from any means of in«
vestijgAtio^ we possess. Amidst aJl this unceitainty and apparent
confusion which surrounds us, one fact o! .great importance seems
to be clear, that the shell ofour jjlobe has at some remote period
been in a state of fltjidi,ty, and that from this circumstaDce has
arisen its present arrangement. Now, as we»re only capable of
conceiving two natural causes competent to products such effects,
the enqniTy t:onsequenily rests i>etween thjBSe; and the question
is; ought the present structorre of thB earth to he regarded us the
^bult of igneous ftisiop, or of aqueous solution ? On this ground
two distinct theories have arisen, whiclj were r.gitated witb con-
siderable warmth in former times, but with a still greater degree
of &rdot:ir, and a clearer view of the sutject, in the present day.
These two theories have obtained the appellations of the Plutonic
and Ntpfunian systems ; the latter of which possesses the greater
mimber of advocates. These, however, cannot deny that the
opposite system merits the praise of novelty, boldness of concep-
tion, and an unliniited extent. It aspires, not only to account
for the present appearances of tire earth, but to trjice a plan by,
which the formation ot successive worlds is developed : it at-
tempts to extend that order and arrangement, that principle of
balance and restoration manifest in ail the vairious departments
of nature, to the constitution of the globe itself. With this the-
ory the Neptiinian forms a striking contrast. It presumes not to
carry its researches beyond the commencement of the present
world, nor to. extend them bcybna its termination. According to
this theory, water is the great agent by which the strata on the
sur&ce of the earth have been both formed and arranged. It does
not attempt to deny the existence of subterraneous hres t© a cer-
tain extent, or that man} of the phenomena which strike us most
forcibly have been the results of such an agency, and the fact
stated in the present article is a striking instance, but it denies
tbat the agency of fire is the general cause of the present geolo.
jzical appearances of our globe, and further ^^ertS; that^fire can«
120 M. fylaroch on thf Air Madder 0/ Fishct*
not exist in the interior of the earth, to an extent sufHcient for tli^
production of such effects. While we ascribe the general and r^
gular arrangement oj the materials which constitute the exterior
part of tlie, terraqueous globe to the iniluence of an aqueous agent,
\ye are perstiaded that many of theif frequent disruptions are the
effects of igiation. The volcanic islets that have 1 isen above the
ft,urface of the sea, as those near the Azores, in the Archipelago,
and on the south side of Iceland, as well as the present instance
and the appearance of the adjacent country, are strong corrobo-
rating proofs of the truth of this opinion. There is an apparent
contradiction in the numbers in the early part of this article, for
\vhich we are unable to account*
Report made to the French Institute , on a Metfioir of M. Dela^
ROCHE, on the Jir Madder of Fishes, Bj^ Messrs, Lafecede,
. Vauquelin, and Cuvier.
As several naturalist^ have of late directed their attention to
the air-bladder of fishes, whi^h is too different from every Qtheic
organ, not to excite a considerable degj'ee of curiosity relative to
both its nature and functions ; yet this attention, in these in*
qifiries, as in many others ip comparative afiatcmiy, has given
birth to conjecture and hypothesis, when it should have pro*
duced exact observation and philosophical deduction. As we
consider the historical part of the paper to be interesting, we
aball present our readers with the substance pf it in as few word^
as possible.
' Rondekt, in his Hist, Pise, published in 1554, merely observes,
that the air-bladder exists more constantly in fre&h water ihaii
in salt water fishes ; and that it probably assisted them in swim-
ming. Marcus Aurelius Severinu§ thought the air it contained
was produced with the animal, from which it may be inferred
that he bad not perceived any outward communication. Walter
Needham was the first who undertook any more detailed ^inquiries
on the subject. These he inserted in a work printed in l66S, in
which they woyld not have been expected ; namely, in his 3ib^
^ioth, de Magnet, He adopted the general idea relative to the
utility of this bladder in swimming, and explained why flat fishes
did not need it. He described the two tunics 6i this organ, the
varieties of its form, and the origin of its canal of communica*
tion. He shews that the vessels are more than requisite for its
nutrition, and thinks that some organic functions are exercised
hy them; he also imagines that the blood they contain has
some connexion with the air. But as it is difHcult for the air to
penetrate from without in certain fishes, he conceived it to be se-
creted there, and te proceed thence into the stomach where it
assists the process of digestion ;. an\i he poij;its out th^ red bodies
Jf. Dckrockt on the Air-Madder of Fuhes. ISl
^hicfa perform this secretion in the snake. BortUi explained, in
1676^ in. his De Mot. AnimaL^ how the air.bladder is used ia
swimmiogy and observes, that when the air.bl&dders of lishe^
bursty they remain a^ the bottom of the water, as well as those
which are natuȣiUy destitute of it; and Concludes that it is
designed for jthe purpose of maintaining an equilibrium between
the specific gravity of the fish and that of the water; thus, by
either enUrgiag or compressing its contents, it adds to the faci-
lity of ascending or desct^nding, as occasion may require. He
supposes that th^ communication between the air.bladder and
the stomach must afiPurd the means of either varying nv renewing
the quantity of air which the former contains ; but he has nei->
tber described the varieties of its structure, nor determined in
what fishes it exists. Redi resumed the observations of Need*
ham in his Observations sur les Anmaux vivam cofUenus dans Us
Anmaux viva/is^ published at Florence in l6S4. lie adds some de-
tails respecting such tishes as hav^ no air-bladders ; and the red
bodies found in the interiyr of these organs. Ue also states his
having sought in vain for the canal of c3mmunication in certaia
sea fishes ; but tliought his want of .success was to be attributed
to the inaccuracy of his observations, Raif and Wilhughby, Hist*
pise. 1680, disputed the idea of this air being used in the pro-
cess of digestion, and reduced the functions .of- the .air-bladder
to its use in swimming, according 10 the noLiuns of Borelli. The.
same opinion relative 10 this bl&d4er >was also sup[)orted by Fres-^
fOHf in the 19th volume of the Philosophical Transactions; by
Ptrraulty in his Mccanique des Animaux^ published in 1721 ; and
by FetU^ in the Memoirs dc VAcademie for 1733. . Perrault, bow.
, ever, made the important observation, that there are fishes with.
out any canal^ and that it is in these that tiie red bodies are
found which are intended for Uie separation of the. air. He like-
wise adds, that in those whic)i have a canal, tjie air, when com-
pressed, dcfcs not issue from the bladder : a remark too much
generalized. Petit, in opposition to this, thought be had disco-
vered valvuU in the canal of the carp, which admit the air to
escape, but not to return, Notwithstan^iing PerrauU's pbserva-'
. tions, Artedit in his Partes Pise, 1738, still ascribed to all air-
Madders a carial intended for the introduction of air ; hut there is
no opinion given, respecting their use^ except that by Borelli.
GouoHy Bhckj and some other authors who have written upon
the subject add nothmg essential to the details that had previ.
ously been given. Besides this principal use of the air bladder
in fishes, some have supposed that it had others which are of an
accessary naiu.re« Of this opinion was Vitq d*Azyr^ who, in his
Memoirts PresejU/Sy 177 ^x supposed that the air originates in the
stomach, and, charged with nutritive particles, thence proceeds
)Bto the air*. bladder, in order to be absorbed by the vascular &yf>'
Vfim* Neafl^ the same is the opinion oi Brouumnct^ in Van Posit*
i22 M. Ddaroche on the Air Madder of fishes,
circ, Reii>ir,y while Erxlcbpn, in a tnenioir on the subject, printed
in 177^, is of tlie same opinion relative to the production of the
air, but coincides with the common notion with respect to its
nses. , These tliree anatomists, however, do not seem to ha^v^
known, that the communication btstween the stomach and the
air-bladder is frequently wanting. This circumstance is strongly
insisted upon by Kochlreutcr, in his Nov. Comm, Pdropaht. 1775,
Having ascertained this, and described the organization of the
red bodies, he maintained that thft air is separated from the
blood in the bladder, but he seems to have been unacquainted wiih
the works of P^rrault and Keedham. Lrskr^ in his Nat, Hid.
adopted the opinion of Koehlrcuter. Monro, in his work nn
fishes, has added but little of importance to wliat was previa:' /':
known on the subject. He made the same distinctiofi with " ;-
rault, relative to the secretory bodies, and re?niv:;^-t :, ^ \\ ^
genus anguilla was an exception to the rule, fi ;• " . '.-.■_ r v.
the canal and red bodies. Mr, Fischer^ now proie '" r .^^s
cow, published a dissertation on the suLj'ct, in 1793, :.» vi; . !<
after noticing the writings of bis predecessors, ai^d gv nc, } ^-
own experiments on the tench and carp, states it as his Oj.ir!: r-^
that besides its ust in swimming, the air-bladder is also a -i.p-
plenientary organ of respiration ; and destined to absorb tl"? <>xv»
gen from the atraotpheric air in water, in the same manner as *ie
supposed the giils to ^l^sorb the oxygen of the water itself by
decomposing it.. A/, dc Lapecede thinks that the air-bladder of
certain fishes may be filled with Ih^ gasses resulting from the
decompositions whieh their respiration occasions ; and mentions
his having collected hydrogen gas from the air-bladder of
tencl.es. AL Davermn/y editor of that part of Cuvier's compara-
tive anatomy relating to the air*bladder of fishes^ adopted, in
common with M, Cuvier, the opinion of Needham and Koelilreiiter,
respecting the production of the air in the bladder by secretion.
He thinks, from the absence of the air-bladder in many sorts of
fishes, that its functions cannot be very essential to life ; and
concludes from various comparisons, that it is an organ inti-
mately connected with loco-motion. He also expresses his sur-
prise at the discordance obtained from different analysises of the
air contained in the bladder: Mr. Fourcroy and others having
obtained little besides azote; M. Configliali obtained 40*0 of
oxygen ; while others, like Mr. Broadbelt, found the quantity to
be variable according to circumstances. M. D. concludes by
suggesting the necessity of philosophers inquiring into the limits
of these variations with a view of deciding a great number of dis*
puted questions ; and Messrs. Gceffroy, Vaiiqueliny and Hiot have
recently made a great number of experiments of this nature.
Mr. Blot found that the air contained in the bladders of several
fishes of the Mediterranean varies from pure azote to 87*0 of
o«cygen, with very little carbonic arid, and without fkoy by4FO«
Mi Delarocke on the Air-bladder of Fishes. IfS
gen; he also, in general, found Ibat the quantity of oxygen waf
greater in proportion to that of the hydrogen as the iish was
caught at a greater depth. He hkewise remiirked that when fishes
weie suddenly drawn up from considerablp depth, the air-bladder
ceasing to be compresbed by the column of water abote, became
greatly extended ; sometimes so much sn as to be ejected from
the mouth. The experiments of Messrs. Gcoffroy and Vau«
quelin published by Biot, tend to the confirmation of his own,
and agree witli others previously obtained by Fourcroy, who had
found ahnost pure a2ote in the bladder of the carp ; and also with
those of Humboldt on the bladder of the gymnotits electiicus,
which 'consisted of i^6'0 of azote and 40*0 of oxygen.
This is the substance of the whole knowledge that had been
acquired On this subject prior to the reading of M. Delaroche's
memoir to the French Institute. But in order to guide themselves
iu forming a correct opinion, of his theory, these reporters have
noticed two memoirs on the same subject since M. Delarocbe's
was read. One ot' these is by M. Geoffroy, who refers to a
former memoir in which he has developed anatomically the
means by which fishes compress^ or dilate their air-bladders in
order to descend or ascend; and on this subject he is of the sam«
opinion as Borelli, which is the commonly received opinion. The
other of these memoirs is by Messrs. Huniboldt and Proven9al, on
the respiration of fishes. They found the air in the bladders of
river fishes to vary from QpO.to 87*0 of azote; and have even
observed as much as 5*0 of carbonic acid. They caused some
tench to respire hydrogen, yet their air-bladders did not contain
any of this gas ; but when they respired oxygen, the proportion of
that substance in the bladder was somewhat increased. They
also determined that when fishes were deprived of the air-bladder,
they were still able to raise themselves in the water, though they
gen«*rally remained at the bottom.
'^ Thus, in the numerous works we have analysed, almost every
possible hypothesis has been proposed, attacked, or defended, and
examples have been given of almost all the combinations of
organization that could be devised. M. Delaroche had therefore
only to examine these organizations a little further, in order to
reduce them to general rules, and to weigh over again the
arguments advanced for or against every hypothesis.'' It is
an examination of this performance that constitutes the re*
maining part of the present report. His residence at Iirica,
Formentero, and on the coaist of Spain, had furnished him
with opportunities of examining several kinds of fishes which are
only to be found in the Mediterranean sea, and he has given nearly
fifty particular descriptions of the air-bladder of different species,
sooie of which had not been previously described. He treats
successively on the anatomical structure of the air bladder^ the
1 24 JMTv Delaroeke on the Air-bladder of Fuhei.
soorces of the air which it contains, and the functions whi9h i(
exercises. He likewise gives a list of those fishes that have it/
and of those in which^ it is wanting. " What he says on Xht
suhject of the canal of communication also presents a great
nunEiber of novelties. On this head he has madc'sonie very acute
remarks, and has ascertained that this canal is wanting in the
greater part of sea fishes. He did not find it in many of the
jugular or thoiacic classes, which compose nearly three fourth*
of the total species of the fishes with which we are acquainted."
M. Delaroche has particularly studied the red bodies with which
tfee air-bladders of certain fishes aref furnished, and has gives a mi-
nute description of them in scveial kinds. The authors of this
report state that they have verified his descriptions as far. as
opportunities had offered, and that they had generally found them*
Correct. And though they difler in opinion from the autiiOr of
these researches, in some respects, and adhere more strictly tor
the opinion of Borelli respecting the use of the air-bladder, yet
they think this memoir is worthy of the approbation of the class ;
and from the great number of new and correct observations it
contains, respecting the anatomical, structure of the air-bladder
and the sources of the air, they recommend it to be published
among the memoirs of Savons Et rangers.
»
Observations, — If we consider the vast extent of that depart-
ment of natural history which is denominated Ickthyolorry, we
shall readily be convinced that there is no one branch ojf this kind •
of knowledge with which mankind iji all ages have shown thenri<A
selves so little acquainted. This, however, will not be matter
. of surprise when we reflect that the subjects of which it treats'
exist in an element so different from our own, and at such depths
that there is reason to suppose gr^at numbers of entire genera
have never yet either been forced by accident, or dfagged by htb»
man skill from their natural abodes and brought within the pale,
of scientific examination. Though, in an uncivilized state of so-
ciety, fishes constitute a considerable part of human subsistence;
yet those resorted to are both few in number, and such as are
most easy to be obtained. Even many ages must' be SHffered Id
dapse, and nations most have advanced far in th6 paths of know-
ledge before they extend their inquiries beyond the confines of
ichthyology, or obtain any considerable acquaintance with the
inhabitants of the ocean. In the unfathonied depths of that tur-
bulent and extensive clement, it is not improbable that million*
reside, which are secluded from human observation, and even of
the few which the'industry of man has at last drawn from their
hidden abode, little more is known respecting them than ttieir
external figure and names. Their foo8, their longevity^ their me*-
tbpd of propagtting their kindy and the wbok of their mannerr
itain and Meteorological Tableh 1 45
ind ccoflomy, remain still among those numberless secrets of
nature,* \Vhich the ingenuity of man has hitherto been unable to
f xplore^ The natural history of iishes has therefore seldom been
ifound interesting, because destitute of that information which it
is the province of history to convey: and ic will not be hazarding
too much to assert that it will ever remain more imperfect and
obscure tban that of quadrupeds and birds^ in proportion as the
fclement which fishes inhabit is more inaccessible to the cu-
riosity, and impervious to the researches of .man. On this ac-
count all inquiries that have a tendency to illustrate this, difficult
part of natural history ought to be received with candour and
attention, and valued not only in proportion to their success, bu(
also to the difficulty of conducting them.
Among the various organs which constitute the aniiiial econo«
.my, and perform the functions necessary to the existence of active
liie, there are some respecting the use of which physiologists
differ in opinion: of this kind is the air bladder in fishes. This
sipgular organ^ which belongs only to this class of animals, and
is not found- in all the species, exhibits so many varieties, as upoa
a slight if^spection of its general appearance it does dot seem to
perform the same functions in each individual. In some fishes
it has a communication with the stomachy in others it id destitute
of this, and is furnished with bodies of a peculiar nature, of a red
colour and iamellated structure. There are also some bladders
that have both these red b()dies.and the canal of communication ;
and a few are supplied with peculiar muscles, i As the object of
Mr. Delaroche's labours was to inquire into the nature and uses
of this singular organ, and the inquiry appears to have been cqn-
ciucted with greiit ingenuity and ptr^everance, we doubt not that
his memoir will be perused by the iciiihyological physiologist with
considerable interest. But as we wished rather to present our
readers with the brief historical sketch comprised in this article
than to enter into any particulars on the subject, we must close
these general remarks, by ol^serving that the observations conr
. tained iu this report possess marks of that acuteness which has
already obtained Mr. Cuvier 6uch a degree of celebrity as a na-
turalist.
Table of Rainy that fell at various placeB in the y^ar I809> l>y ^^^
Jl«?. J. BLANCHAtiD, of Nottingham ; with a Meteorological
Table for the same year^ by Dr. Clarke, of that Town* — FhU»
J&um, No. 114.
O^ the eleven places mentioned in this table, given by Mr.
Blanchard, the greatest annual quantity of rain fell at Dalton in
Lancashire, and is stated at &b'Z6 inches. The least quai;itity
No. 24.-— VOL. VI, s '
It6 Rain and Meteorological Tables.
was at W«st Bridgford, in Noltinghamshire, and was 17*55^
incbes. The greatest monthly quantity at Chichester and Chats-
worth was HI January; at tho former it was 8*44, and at the
latter 5*22 inches. At Chichester there was no^ie in March;
and at Chatsworlh the least quantity fell in October, and was
0-28: the total at the two places being 38 07 and 29'9l inches.
At London the greatest and least quantities were in July and'
October; ibe former wag 3.38 and the latter 0*22 : the annual
quantity was 24*95. The greatest quantities at Horncastle,
Ferriby, near Kingston-upon-llirH, ^^€alh, near Wakefield, York-
shire, Lancaster, Dalton^ Bridgford, and Nottingham, fell in
August; and were respectively 4*53, 5*88, 4-6l, (>*12, 7*25, 375,
and 4*50. The least quantities at the following places were, at
Horacastle, in October, 0*75 inches ; at Ferriby, in May, 0*45 ;
Heath, Manchester, Lancaster, and Dahon, in March, and 0*43,
0*35, 0*55, and !• 13, respectively; Nottingham, October, 0*31.
The total quantities were, at Horncastle, 28*38; Ferriby, 27,^7 ;
Heath, 31*65; Manchester, 29*10; Lancaster, 41*73; Notting-
ham, 2301.
Ill Dr. Clarke's meteorological table it is stated that the highest
observation of the Th^rmoftieter wa« on the 27th of July, and was
78% wind S. The lowest was en January 22nd, 17% wind N. at
2 miles distant from the town, it was 14** on the same day. The
greatest variation in the space of 24 hours, was 18**, June 1st —
Snd; and the mean annual height 48*''78. The greatest height
of the Baromettr was June 25lh, 30*45 inchei, wind N. E.
Lowest, December 17th, 28*25, wind W. Greatest variation
in 24 boars, January 30th— 31 st, 1-13 inches; and the mean
annual height 29*74. Dr. C. al-so states that the wind was m
the N. and N. E. 130 times; E. and SE. 79; S. SW. 197;
and W. and NW. l65 times in the course of the year. The
number of fair days >^as 234, and of rainy ones 131. On the-'
19th of Aprily snow fell to the depth of a foot.
Obseriatiwfs,'^ At page 350 of our 5th volume, we noticed two
aimilar tabled by these gentlemen-; and we hope that in future we
shall have similar tasks to perform. By comparing the twa
abstracts, it will be seen that the greatest monthly fall of rain in'
tlie former year was chiefly in October, in the latter, in August:
aliso, that the total quantities which fell at all the places in lft09»
considerably exceed those which fell at the same places in the
preceding year, except at We»t Bridgford; and the observatirtns
there appear to be incomplete, as the columns for Febxuary and
May are suppliedv with dashes instead of ^gures, whereas that
of Chichester for March, where there seems not to have hetst
any, is occupied by ciphers. There is likewise a considerable
di^rence between Uie greatest heights of the thermometer, for
Mr. Williams on Ax'iMtdhal Refraction, \^
fine tjjro years, it being 11°. Tbe greatest height of the tbcrmo-
met-r at Loudon was on the 25th of July, and is stated at 77°;
but as this observation was made at noon, it is probable that it
was higher a little later. It is also remarkable that the least
height or the thermometer at Nottingham, should not only hap-
4)en on the same day, but be exactly the sante degree, in each
year. May not this lia-ve been a mistake in, copying? The least
jheight at noon at London was on the 18lh of January, and was
26 . There is likewise a difference of 1*06° in the annual meaa
of the two years. Tbe greatest height of the barometer at Lon.
don was on the 22ad of July, when it attained to 30*6; and the
other extreme happened on the same day as ^at Nottmgham«
when it siink to 28' 3.
On Azimuthal Refaction, By Mr. Charlss Williams, — Phd*
Mug. No, 144.
Os the 28 ih of last February, as Mr. Williams was crossing
jsome higii fields to the suutb of Primiose Hill, about nine A. M.
he observed several objects assume a distorted appearance, and
that the spire of Ibliiigton Church appeared crooked, and in a
few minutes aftcrwaids about 20 feet of the upper part of it
.seemed to be separated from tbe rest, and removed to .the right
Land of it. Mr. W. therefore screwed his tdescopc into an
adjoining post, but before\he couU adjust it, the Aspire becatne
indistinct, being wholly envelope^ in the fog. Hfi then dii;ectecl
the telescope to Hampstea^, the tipper part of which was' visible,
but a thick fog rested on the bottona of the hill. Having obtained
a good in^ers.t^tiou, and found the telescope to remain quite
steady on account of the calmness of the day, he soon observed
the tower to iecrease in height, and shortly after the upper pari
appeared separated from tl\e lower, when the latter seemed to
retire to th]^ left, but the former remained stationary with respect
to azimuth, but increase^ in altitude; in three or four minutes
the top was considerably elevated, and appeared as if rising into
a cloud. The bottom part was about one sixth part of the whole
diameter of the tower to the left, became hazy, and in that
situation it disappeared. I'he telescope remained stationary till
the* tower again became visible, when the two parts appeared to
be joined, and in nearly the same situation in which the iower part
was last seen, and continued so till the telescope! was removed*
Mr. Williams also adds^ that a gentleman stated, that in the
^course of the same day, ^* one end of a row of houses near Holr
loway appeared to him at first much higher and afterwards
much lower than the other, although he did not change his situa-
tion:— and another, that the top of Primrose Hill, with some
p£fsous on it, appeared to him separated from t)ie bottom and
12? Mr. Jfdiiams an Azimuthal Refraction.
floating in the air, and that he bdd seen a simiiar eflfect on othe)[
liills several times before."
Observations, •'^That the lower part of the atmosphere is
subject to several variations which are not nisily accounted for,
has long been known to philosophers. A sudden change in it*
' temperature, density, or other circumstances may effect changes
in its refractive powers, and render them liable to great uncer-
tainty. The cause of this uncertainty, however, appears to be the
great quantity of vapours, and exhalations of various kinds, which
are suspended in the air near the eirth's surface, and the different
yariations to which these are constantly subject. That this is
'the case seems evident both from the present in^tnnce and
several others that have been previously recorded. As some of
these are highly curious circumstances, and. perhaps not very
^familiar to many of our readers, we shall give a brief account of
tbe principal; with the respective states 6f the atmosphere at the
time, as far as was observed, as it is from a combined collection
of both these kinds of observations that the cause^(>f unusual ap-
pearances arising from refraction is most likely to be determined.
M. Picard found that refraction was greater in winter than in
isummer, and in the night than in the day. He also observed;
that during the time that the upp(*r limb of the sun appeared in
the horizon until its lower limb came into the same situation,
the refraction- had diminished 25''^. Bouguer also observed in Ame-
rica, that the refraction was greater in the night than irt the tlay
by about l-6th or l-7th. Dr. Kettkton measured the altitude
of a hill on a clear day, and repeated the same observations when
the day was cloudy and the air gross, and found the angle in the
latter case to be considerably greater. He likewise observed, thiat
.. the altitudes of some hills which he measured appeared to be
greater in the morning before sun rise and late in the evening,
than at noon in a clear day. M, Monnifr observed at Paris,
during the great frost in 1740, that, when the thermometer was
10° below the freezing point, the refraction was 10' 15'''^, at an
elevation of 4° 44:|'; but when the thermometer istood at 24**
above the freezing point, the refract on at the same altitude was
reduced to ^^ 20^'', consequently there was a difference of H 55^
for a change of 34° of the thermometer ; the mercury in the
barometer stood at the same altitude at the time of both ob-
servations. '
The variation and uncertainty of the dip of the horizon in
different states of the air, taken at the same altitude above the
level of the sea, induced Captain Huddart to make- observations
on horizontal refraction. In%the course of these h^ often observeid
that low lands and the extremity of head knds^or points, forming
an acute angle with the level of the sea, and viewed from B
distance beyond it^ appeared to be elevated aboy^ the sea with c^
i
Mr, WUUttmson Azimutkal RefracHon" 129
9pen space between the land and the water. He states, that the
(nost remarkable appearance of this kind which he witnessed
was* at Macao, where, lor several days previous to a typhoon, the
points, of the islands and the low land appeared higher, and
the spaces between them and the sea greater than any other he,
had seen. This he thinks, arises from, and is proportional t<^
the evaporation going on at the surface of the sea ; and that this
evaporation causes the maximum density of the atmosphere to be
at some distance above the surface of the earth, from which alti^
^ude it decreases both ways. He states some other observations
which tend to the confirmationof this theory., in the year 1793f
when residing at AUenby in Cumberland, Mr. Huddart made
some observations on the Al^bey Head in Calloway, about seven
kagues distant, and the window from which the observations were
made, was about fifty feet above the level of the sea at that time
of the tide. There was a dry sand between Mr. il. and the head
land, at the distance of aoout thr^e or four miles from his sitna*
tion, over which the horizon of the sea was seen ; and this sand
was then about three or four feet above the level of the water.
The sharp point of the head. land appeared blunted and elevated
above the sea, and a part of it entirely insulated, and considerably,
raised above the watej \^ith an open space between them. A part
of the Abbey Head ako frequently appears to be fTeparated from the
rest of the land at a much greater distance from the shore than
in the present instance.' This observation was made ip the after-
noon, and when the intermediate sand contained very little mois*
ture. At another time when the land app<-ared elevated, Mr. H*.
/directed his t( lescope to a small vessel about eight milts distant,
which appeared to be elevated c^bove tbe w^ter, and iq have an in-
verted image below it, the mast of which seemed to penetrate the
surface of the sea. In this observation the telescope was about
forty feet above the level of the sea, and the mast of the vessel
about thirty-five feet. The barometer was at 29'7 iaches, and
the thermometer 54°. Some other appearances of head lauds,
and the circumsta^nce of the Portland lights appearing much
brighter when they are seen near ibe horizon of the sea, are
stated by Mr. H. in the Philosoohical Transactions for 1797.
Other appearances also of a different nature from ihese de-
scribed by Mr. Huddart, are son^etimes found to take place; and
^he Rev, S. Vince, of Cambridge, had an opportunity of observing
several of these at Ramsgate, on the Jst «)f>AHgust, 1788, be-
tween half^ past four in the afternoon and seven in the evening.
1 he day had been very hot, and the evening was sultry, and the
^ky clear, except a lew /lying clouds. These pbenomeni^ were
observed with a telescope, which magnifies between 30 and 40
^imes, but they \\.ere visible to the naked e^^e. The height above
fyp level of th^ sea, at w))ich most of the observations werema4^
J 30 Mr. Williams on AzinuUhcd Refraction^
was about 25 feet ; some of them, however, were made at ^n ei^f
valion of 80 feet ; but it did not appear that the phenaR»ena were .
altered by varying the height at which they were observed, flav*
ing directed the tele&cope at random, with a design of examining
any objects that might be within the field of view, Mr. V. saw
the top of a ship's mastfe above the horizon of the seh, and • t-r-
tically over this vessel, two complete images of the ship v'ith
their hulls joined, were distinctly visible in the air. The upper
one of these was erect, and the lower inverted. 'I'^-is appearance
was so Strang* and unexpected, that he desired a person present
to look through the telescope and dpscrib* what he suw ; h)> de^
scriplion exactly corresponded with what Mr. V. had himself ob-
served. As the ship receded from the shore, le*^ and less of ^he
masts became visible, and the images ascended ; but a^ the ship
did not descend wholly below the hori^^on, he had not an oppor-
tunity of observing, at what timt and in what manner, the
images would have vanished. Being deirou? to observe w!ietht»r oi
iiot tlie same effect was thus produced on other ships at the sduid
time, Mr. V. directed his telescope to another ship, the huil of
which was just in the horizon, and beheld a compUte inverted
image, the main mast of which just touched that of the ship it-
self. This ship continuing to move on the horiaon, the image
moved with it without variation. The next ship which was ob-
served, was so far beyond the horizon, as jnst to prevent her hull
from being seen, and only a part of the inverted image was seci^
abuve it. As the ship descended below the horizon, more of th^
image gradually appeared, till at last they separated from each
other, but no second image was observed as in the first instance,
when the ship ceased to descend. Another ship \vas also ob^
served with its masts just above the horizon, and two well defined
images appeared above it, as in the first case, but with this dif*
Terence, that they seemed to be separated at the same time and
the sfea was distinctly visible between them. As the ship ap-
proached the horizon, the erect image gradually disappeared, and
at last vanished ; the image of the sea also vanished afterwards,
and the inverted image of the vessel continued to descend^ but the
ship did not approach sufficiently near the horizon to bring the
extremities of their luasts into apparent contact. The clifis at
Calais being visible at the time, the professor next directed his te-
lescope to them, to ascertain if there was any thing peculiar in
their appearance, when he perceived a'distinct image of the clifis
above the cliffs themselves, with an image of the sea separating
them. These images vanished for a short time, but they soon ,
loecame visible again, and assumed exactly the same appearance
as before, but soon after vanished altogether. A ship with its
hull beMw the horizon passing these clifis, exhibited an inverted
image against their surface. Some time after, two partial ele^
Mr, Williams oh AztmMal Refraction. 131
vaiions of the sea were observed in front of these cliifs ; these
were equally distinct in every part, changed their figure a little,
ind vanished in the place where ihey were first seen.
About this time a thick fog came on the, horizon, from the
other side, rolling with great velocity, curling as it went, like vo-
lumes of smoke from a chimney. Mr. Vincc, therefore concludes,
that, at the time of his observations, there was a considerable fog
on the other side of the horizon. He also observed several partial
elevations of the sea which moved parallel to the horizon with
great velocity. From this circumstance he remarks j " 1 conjee^
ture therefore, that these appearances were,' in part at leas^v
caused by the fog on the other side of the horizon. For though
] did noiy at the same time, see the motion of thes6 images, and
that of the fog, yet fjom memory I judged the motions to be
equal : and they were also in the same direction. A fog, which
by producing an unusual refraction, might form 4JKe66 iniag^^
would, by its motion, produce a corresponding motion of ' these
images." Professor Vince likewise remarks, that there was not
any' log on the near side of the apparent Ijorizon, nor did the ships
exhibit Hoy particular appearance. The common refraction at the
time, appears to have been unusually great ; for the cliffs at Ca.
lais could be seen from the edges of the water considerably ele-
vated abt)ve the. horizon, though they freqitently cannot be per-
ceived in clear weather Irom the highlands in the neighbourhood.
The French coast also appeared to a much greater distance tharf
Usual, and particularly towards the east, where the unusual refrac-
tion was the strongest. J\Ir. V. examined all ships in sight, daily
for about five weeks afterwards, but did not perceive any similar
appearances. On the 17th of August, about half an hour after
three in the afternoon, however, he observed a ship with an in-
verted image below it, similar to that observed by Mr. lluddart ;
but their hulls were separated by an image of the sea. At the
time of this appearance the ship was approaching towards the
horizon, and as it advanced, the image gradually diminished, and
totally vanished when the vessel had attained that limit. These
tffects Mr. Viuce ascribes to a variation in the refractive power
of the air, and illustrates his explanation by a diagram, for both
which however, we must refer our curious readers to the Philoso-
phical Transactions for 1799*
We shall now conclude thes^ observations with remarking, that,
from the circumstances attending these appearances, it is evident;
that. they all took place at tin;>es when the coi^mon atmospherical
refraction was much greater than it is in general, and that the
suspension of vapoui in the air was either wholly or in great part
the cause. Such a concurrence of circumstances, however, seems
to be necessary to their production, as does not pften happen at
the ^xnt time and in the same place. There cannot be the least
132 Dr. Bosfock and Mr, Foster on ^tetcorolo^y.
doubt, that vertical refraction is subject to considerable vafiatioif
near the horizon, according to different states of the atmosphere i
and as these variations may exist under such circumstances ^s t<y
produce images both erect and inverted, and both above and be-
low the real object ; we think it is not difficult to conceive sucfcf
ji horizontal variatioh in the refractive power of the air, as in
combination with the vertical variation, would produce the ap-
pearances observT'd by both Mr. Williams ofi the spire of Isling-
ton Church, and the tower att Hampstead, and by Mr. Huddart
on the Abbey Head, in Galloway. As it would evidently be of
great importance in many ca^es to ascertain the nature of a ship,'
Avhile the top of her nmsts only are visible, we think that the ex-«
amrnation of vessels at this time of their appearance, is a sub-
ject which demands the attention of naval commanders.
■tassssssa^dBaBBBsI
1. Remai '. ^ upon Mtteorohay : with a specimen of a new Mefeordlo'
gical laUc, B^ ^* Bostock, M,D, — Phil, Journ, Aos, 11,3
and lid.
t. Ranarks on Meteorohgy, By Tpioma? Foster, Esq.^-^ibid*
Nu. 1 14.
i. Dr. Rostock remarks that predictive Meteorology is thsii
toart of the science which is of the greatest importance, botn fromf
Its connexion with the great operations of nature and its practi-
cal utility. This part ot the subject he thinks must be founded
iipon observation ; and notwithstanding it has engaged the attend
tion of many philosophers for a considerable time past, and se*
-veral meteorological tables have been published in different partd
6f the world; the benefit resulting from th^se, has not been equi-
valent to the trouble ol their formation. He also remarks, that a
greater degree of this practical knowledge has beeft attained by
men accustomed to be much in the open air without the aid of
science, than all the roles of philosophers hdve yet b6en able to
impart : but the knowledge thus acquired is unfortunately almost
^Iways confined to the individual who possesses it ; on account of
his inability to communicate to others the reasons by which his
own judgments have been formed. Dr. B., however, is of opi-
^hion, that these two modes of obtaining meteorological knowledgij
may be combined, and this is the object which he has endeavoured
to obtain. To this purpose he observes ; " although my mode of
life, as a resitJent in the midst of a large town (lAvefpooU) had
been unfavourable to such pursuits, yet I think that I Irave not
been altogether unsuccessful m my attempt; some points of kn-'
Jortance 1 consider myself as having ascertained, and many more
ave suggested themselves, which a longer series of observation*
must coAfirtn or refute. My plan of observdtion; as it appearsf.
Br. ^Bostock and IStr. tost^ on Mdeorotog^. 133
^sHitially consists, first, in ^ayiog a constant attention to atmo-
^hericai phenomena of al) kinds ; and secondly, in adopting a
nomenclature, by which these phenon>ena may be accurately
T-ecorded, and by which the observHtions* made at different tim<es,
tind at different places, may be compared together/' The meteo-
rological joiirnajs which have hitherto been published, he consi*
'^ers as inadequate to this purpose; as what they contain, though
necessary to be tnown, are by no means tbe most important
object^ of a\teuti(iii. V.'liat l)r. B. considers "as such, are
^ist, the nature and thape of the clouds, and the progressive
cTianges which tliey are ujid^rgnibg ; secondly, the relative state
of the barometer, whether rising or falling, and with what degree
^f rapidity ; and thirdly, the relative stat« of tlie windi whetllci
increasing or idiihinishing, whether it has lately changed Us direc-
tion, aiid from whiit point it pi«oeeeded before its .clmnge. Th6se
Arc th^ o4)ject8 to which the attiention should be uniformly di-
j^ected, and whi^h mav l>e c()hsidered as the basb of all nieteoro^
k)gical predictions. Tliere are also a number of accessary. cir«
•cuoifitaiices that may be occasionally employed. Of th<^»
ibme 6f tlie tnust important are, tiny sudden or t^markable
changes ki the temperature or humidit)' of Clie atmosplvere; the
ilspect of hioiintainA br i>iher distadt objects ; .the appearance of
(be hbrison as contrasted with the higher regions of the atmo^
sphere t tlie «tate df the bir as to fogs, mists, dew, ha^e, $;c. ;
the electric Mate of tbe air; the manner in which smoke is
]|ffected in passing from ^ chimney tops; and the state of evapora-
iion Trom tbe siii-fac^ of the earth." - . . >
These remarks are followed by a specimen of his diary fur
Septtmher^ 1809* Of this we shall transcribe the first three day9
as an example of bis ifiethod, and then give his own explanation
#f the diary Of which they form a part.
^* SiPTEMBEli, ISO9.
J. iE 2572-;-Partially clear, some light (blonds, nearly
t
SE
2
calm. Continued all day nearly clear and
29'fia — calm with a gen tie breeze. Evening clearand
calm; a very pleasant day. Mountains
clear, but hgbt. No tufts or lines, but
a few small rouiid, dark clouds; afternoon
transparient.
• •
SE 29 'Co— Uniformly cloudy, gentle breeisc^ After-
3 wards some break«t, the brcere increased.
At noon some rain came on for 2 hours.
Afternoon cleared partially, and wind
went to E* '1 hen some h«avy brpiea
'1 3^0. 2-1- — Vol. vi. t
3.
E
6
E
5
E
3
^4. Dr. Bostock and Mr. Foster (mMtteorotogf,
29*50«-CIoud8, and ai| imperfect arc between S
and W. Evening wind high, partially-
clear, driving showers in the night. .
^9'48 Fresk breeze, heavy clouds, tendency to
rain. Forenoon more clear and less
windy. Afternoon a heavy shower, then:
partially clear, and a gentle breeze.
29'^0 Evening some lightning. I'he state of
tbf atmnsphere, which produced the
squall of the 2d, now changed, but
wind still £.
This diary consists of two columns, the first for the direction
aid force of the wind, the second for the height of the barometer,
and to tliese is appended a large space for occasional remarks.
For the direction of the wind, I think it sufficiently minute to
divide the compass into l6 points; N, NNE^ N£, ENE, £, 5cc.
for the otlier quarters. The fo^ce of the wind is comprehended
under 8 general terms, which have each their appropriate figure.
1, calm ; 2, nearly calm ; 3, gentle breeze ; 4, breeze ; 5, fresh
breeze ; £, windy ; 7» high wind ; 8, violent storm. There are
some other circumstances connected with the wind, whether the
force be uniform or whether it be irregular, what is usually called
squally, whether it be increasing or diminishing at . tbe time of
observation, whether it blow steadily from one point or veer
about; whether it shift irregularly or revolve gradually, and
lastly, whether it appear to extend high into the atmosphere^
or only affect the lower stratum/'
Dr. B.'s next object^n tkt» communication is to explain suck
terms of his nomenclature as occur in his occasional remiirks*
The height of the barometer is taken between ei^ht and nine ia
the morning, and at the same hour in the evening ; but its abso^
lute height he (Considers of much less importance, unless it be
known whether it be rising or fatling at the time of observation.
The phenomena of the clouds constitute a principal part of Dr.
B/s system, and a variety of terms are employed to designate
their, general shape, size, colour, density, height, motion and^
cither particulars. Besides these, it' sheuld be observed whether
their magnitude be increasing or diminishing: whether any
change be taking place in their distinctive characters, and whe*>
ther one species of cloud be gradually changing into another;
and what is their respective relations to the state and directio|i
ofthewilid. By a transparent oKmoiphere, as mentioned in' the
riemarks on the first of September in the above specimen of the
diary, is tb be understood a state 4n which moderately distant
o1>jects assume a peculiarly beautiful appearance : and this state
ke illustrates by saying it is like a'picture very highly varaisbtd.*
Dr. Bostock and Air, Foster on Meteorolo^, 13$
iThis transparency seldom lasts more that a few hours, and gene-
rally takes place before the sun sets, which is frequently atcomf
panied with the most brilliant colours. This transparent state^
Dr* B. regards as one of the most infallible signs of rain : this
took place in the instance referred to. The particular formation
of clouds, which is denominated an arcy September 2nd, consists
of a body of clouds extending in nearly parallel lines through a
considerable portion* of the visible atmosphere, and converging
towards a point near the horizon. Tbese lines sometimes ter-
minate in a similar manner at opposite points of tiie horizon,
and at others they do not extend beyond the zenith. If this arc
be composed of parallel lines it is termed a iviear arc ; when it
consists of rows of small clouds, a mottled arc ; when resembling
a volume of smoke rising from a chimney, a wreathed arc ; and
when it has the appearance of feathers, a feathered arc. Indepen-
dant of any particular shape, it may be either perfect or imper-
fect, and either increasing or diminishing ; forming a precipitating
or dissolving arc. It also receives the denptrii nation of Hprment,
past, or future arc, as it coincides with these different states of the
wind. A present arc always indicates that the wind will soon
change from the point which forms its present direction, and
when it arises from a S* or W« quarter, it will generally proceed
to the right or left hand, as the barometer is rising or falling at
the time ; the observer being supposed to face the point of th«
horizon from which the arc proceeds. When a future arc is
formed on the left hand of the wind, and the barometer falls, it
indicates that the wind will move into that point. Dr. B. desig-
nates that a revolving day^ in which the wind gradually moves
round through the different points of the compass : as these revo-
lutions are in the same or a contrary direction to the course of
the sun, they are denominated direct or reverse. A direct revolu-
tion often takes place in the most settled state of tbe atmosphere ;
but a reverse revolution is a very general sign of r^in. When the
Tvind is €ast, accompanied by a low. and falling barometer, it in-
dicates that the atmospherical electricity is in what is termed a
negative state : this is called a negative day ; and in cold weather
this state is generally either attended or succeeded by the hea-
viest falls of rain, but in summer by a close, oppressive state of
the air, and thunder. The usual east winds are generally accom-
panied by a high baromet<»r, and a strong positive state of elec-
tricity. By shaded clouds is meant those consisting of rounded
masses, one side of which is niuch darker than the other. When
a* part of the horizon is occupied by large rounded clouds which
appear to be heaped upon each other they are named pUed clouds.
When the wind changes into a southerly point after the influx of
^ cold current from the NW. rain generally ensues. When
plauds sonf ewhat rtsemble bunches of hair they ar6 called Tufts ;
18 ff I?/'. Bostock and Mr. Foster on MeUor^ogy,
AXii the larger and more compact masses of this kind are lerme^
fi'ocks. Dr. Bostock then concludes bis second papiT with some
remarks rt'latlve to istorms, and the advantage's that would result
ifrom a number ot* accurate coipparative obserrations on this
sulyect ; ard by restating what he considers the first object '\{k
nieteoFf'logy, and the chief source of its greatest improvement.
5?. Mr. I'oster fully agrees with Dr. Bostock, that the par-
ticiUar inodificatipns of the clouds constitute an essential part
6f meteorology, and expresses his approbation nf tfie plan of the
^iary. adopted by Dr. B., but thinks that the BomendHturcr pub<*.
lished a few years since by Mr. Lake Howarcf, of Plaistow, in
|jis treatise on the various moditication& of clouds, is capable of
clearly expressing these circumstances. JVJr* F.aIt»o recommend^
the following plan for a meteorological dairy. ^' It should consist
of twelve columns beaded' a^ifol lows ^ 1st column, day of the
month; 2nd and Srd, the maximum and minimum of tha
theroioiueter) 4th and 5th^ ditco of barometer; Sth, the quantity
of rsiu which; ialls ii> the course of the day ; 7th, the quantity
of evaporation in square inches; 8th, th« stMe of t(ie hygrometer ;
(Dr tuc's i^ perhaps t\rt best), pth and lOtb, the direction ana
^rce of the wind; 11 th the modiBcations of c\ouds; and tbe
)2th should be reserved for the registc;^ of occasional meteoro*
logical phenomena, such, for an isxample, as tliondcr, storms,
meteors, &c." ♦
. Ohscrvations.'^Tht meteorological student will be glad to
observe, that the publication of tables and ol)servalionS of this
nature has Ix^en more frequent of late, than it was a short time
since. This will appear evident from the content? of our volumes,
AS it did not fall to our lot to notice one paper on this subject prior
to page 162 of volume frve ; but several have sinc<N:ome within the^
province of our labours. ^ Jn the first instance we stated oux rea-
sons for asserting that it w'as desirable, tliat accurate tables
should be kept at a greater variety of places, and air the changes
in atmospherical piienomena correctly noted as they took place ;
and we now agree with Dr. Bostock, ** that the lirst object is to
obtain a fiill historical description of the successive clmnges of
tbe atmoftphere, to notice the periods of their commencement
and duration, and the connection which they have one to the
other. The second great point is to invent some method by
which these changes may be arcurately recorded.'* lie alstr
observes, that, according to his view of the subject, tlte science
6f meteorology must be advanffd, not only by accurate- obser-
vations of individuals, but by the comparison of v^^rvatiou^
made in different places. '
• douds are formed of the watery particles exhaled from the
surface of the earth and waters by the power of tUebuc; aititi
Dr. Bostock aniiJr. Foster on Meteorology. ISJ
tlie vapour thus emitted ts^Ay be decomposed in different ways ; as^
on its first entering the atmosphere, producing a fog or mist.
After having ascended through the ^ warm air near the surface of
ihe earth, and arrived at a colder region, it becomes conder.sed ;
and thick cloiids are generally th« result. It may also l^e
uniformly mixed with the mass of the atmosphere^ and travel
Svitb it to a considerable distance from the source whence it was
derived, and then either fall in dew or be collected into horizontal
sheets frequently at<« considerable elevation above the earth's
surface. The causes of these changes are probably to be found
hi the state of the superior currents of air, which both impart
ftnd carry off a considerable quantify of vapour according to the
different degrees of saturation between these and the lower strata
over which they pass; but this part of the subject is extremely
J^elktent in such observations as could be admitted as proper
4lata in reasoning on this head. It is thought by some pereona
^hat there are only three simple and distinct modifications of
clouds; hot as these different aggregates may, according to cir-
cumstances, pass into each other, and become intermediate or
con) pounded, it is necessary to admit a greater number of modi*
/icdtions, apd to give names to some of the most remarkable
states or appearances.- Some ^i these modifications are tlie
following.
1. Cirrus, Parallel^ fiexuous, or diverging fibres, extensible
in any or in all directions.
2. Cunmhs, Convex or conical heaps, increasing upward
from a liorizon^al base.
' 3. StraiufJ ' A widely extended, continuous, horizontal sbeet,
increasing fr6m below.
4. Cin^mCymiUus. Small, well defined, roundish masses, in
close horizbntal arriingements.
5. Cirro-stratus. Horizontal or slightly inclined masses, at-
tenuated towards a. part or the whole of their circurofer«'nces,
f oncave downward, or undulated, separate, or In groups, consisting
of small clouds, having these characters.
6. Cumulo^tratus, A dense cloud with the ba^e of the cu-
mulus, but its upper part extended into a broad Qat structure.
7. Cwmtlo-cirrjD-siratus^ vel nimbus. The rain dottd, A cloud
or system of clouds from which rain is falling. Jt is a hori«
arontnl sheet, above which the cirrus spreads, while the cun>ulus
enters it laterally, and from below.
But for a more detailed account of thest modifications, and
plates for their illustration, we must refer to Mr. Ha ward's
paper on the subject in the l6th volume of the Philosophical
^lagazine.
( is» )
On the Art of Printing with Stone, and especially on tie Progress
which this Art has made in Germany, Bj/ M. Marcel de
SfiRRKS. Annates de Chimie.
Tre art of printing with stone» wfairh in Germany is stiled
xhemisthe druch rey, or chemical printing, owes its origin to Alois
Senejeltcr, a native of Prague, in Bohemia. About ten years
since he obtained from the elector of Bavaria an exclusive pri*
vilege of exercising this art for the term of 13 years; but be
mftervrards ceded this privilege to his brothers. Some tim«
afterwards he also gave up this privilege to jM. Andre, of OOeih'
bach, who has since exercised it in England, in 1802, Senefelter
went to Vienna to solicit a fresh privilege, from the Emperor of
Anstria, which he obtained in the following year, for the spaca
df ten years. He however soon gave up this also to Messrs;
Steiner and Krasnitzki, and returned to Bavaria; and, in part*
Bership with some other persons, opened a stone printing.house
at Munich, where the art has been brought to its greatest per*
fection. M. Chauvron was ^he first in France who obtained a
brevet of invention to print br engrave with stone; and M.
(juyot has only been engaged in it since his time.
The processes which are used in printing with stone are very
sifnple, and consist of three different methods/ Tlifi first of these,
and that which is chiefly used; is wnat is denominated the
method io relief. This mode is chiefly employed for music.
The second method is the hollow method, and is that preferred
for engravings. The third is the flat method; this is very useful
for the imitation of drawings, particularly such as are to resemble
those made with chalk. To print or engrs^ve according to this
process, a slab of indurated iharle, or any other calcareous stone
H used, provided it can be easily cut, and takes a good polisht
ft is aUo of an advantage that the stone be of a fine giain ; and
the most convenient thickness is from two inches to two inches
and a half. When the stone is dried and well polished, the first
operation is to draw the designs, notes, or letters that are intended
to be printed upon it with a pencil. These are then covered
with a particular kind of ink, which is considered at Vienna as
a great secret. This ink, however, appears to be composed of a
solution of gutn lac in potash^ which is afterwards coloured with
lamp-black produced from burning wax. When the designs or
letters^ thus impregnated with this ink are dry, there is passed
over them nitric acid, more or less diluted according to the degree
of relief it is intended to produce. The acid attacks those parts
of the stone which have not been covered with the ink; while the
drawinc]' ^c. remains untouched* The stone is next wa$lxed with
Af. Marctl ift Strrei on ihe Art of Printing with Stone, iiy
Water to render it clean ; the letters &c. are therf covered with
commou printing ink by means of a printer's ball. A sheet of
pap«r being put into a frame, and lowered down upon the stone«
a brass cylinder is passed over the paper, or a copper-press press
is used. Whtu the required number of copies have been obtained,
the siab is polished again ; and it will thus serve ivr a consi<ier-
%ble number of works.
The hollow method is not much dllTerent from tlvis, except
that the acid used is much stronger, and the design, by its greater
action on the stone, is more in relief, and the stone mure hollow.
This method has the advantage of rftmedying that equality oC
tone which printing in £t;one generally produces. This method is.
sometimes u.scd for engravings ; but is necessarily more expensive
than the former; aud. requires heavier rollers. In the former
of these methods the nitric -ae^ is mixed with one half water*
In the third method still less nitric acid is used; but great Care
must be taken that the stone used is quite fl«it« The design rises'
k'ss above the other part of the surface than in the other methods^*
and is scarcely sensible but by the touch. Tht kinds of worki
that are engraved in stone are, 1. Imitations of wood cuts. 2^
Imitations of the dot manner. 3. Drawings. 4. Musical works*
5.- All kinds of wriiing. 6. Geographical maps. 7- Engravings
in mezzotinto.
i he advantages which. result from this noethod of printing are
stated to be a ||pculiar character that cannot be imitated by th«
other methods, and what is still more important, the facility with.
which it may be executed. On this head it is staled that a
design which would require an artist five or six days to finish
upon copper, may be efigraved upon stone im one or two. days.'
In the same time that the copper plJTte printer draws off 6 or 700r
impressions, the printer oa stone can take off 2,00,0. An en-
graved copper- plate will seldom yield 1000 impressions ; but the
stone slab will yield several thousands, and the last will be very
nearly as good as the first. It has been tried in the printing-
house at Vienna, to take off 30,000 impressions of the same
design i and even then the last of these was nearly equal to the
first. Th^y are 'even said to have carried this number of copiear
to a greater extent in the printing bank notes. The most
hidustrious ancb .skilful engraver of music cannot engrave more
tha.n four pages ^on pewter in one day, while the engraver in
stone <an complete twice that quantity. ** Every kind of work
which artists engrave iipon copper or pewter, and vhich the
printer executes with moveable types, may also be performed by-
using stoae." There is also said to result a saving of one third^
of the expense in comparison of printing upon copper or pewter.
One ef the chief disadvantages attending this method of print*
ifng/ ill the difficulty which is expeiienced in attempting to give
140 • Mr, Walfceron the P'oWerqft/iC Eye,
either to the chaiacters of the impression or to the strokes of tM
e&graving, that diversity of tone which imparts so much value tii
fvorks of this nature. The same inconvenience is also to b*
found in njusic f)ritited in thiij manner; dud the equal tint which
is spread over it renders it less let»ible.
Chauvron, who fir^t established a prifiting-hou^T of this kind at
Paris, firbt traced the lines upon the stone with resinous ink, and*
then moistened it with water. This he wiped otf ligliily, which
soon left the resinous lines quite dry. On applying the printer'^
ball in this statt;, tlibse lines only became impregHated with the
ink, and consequently wer^ the only parts which yielded any imJ
pression. 'i'hose printers, however, who do not ma^ke 6se of any
niti^ic acid, always produce a very infeiior kind of work ; its use,
ther^fore^ cannot be tod stri>ngly rccoiliuieude((.
• ^•"
Obsertatioihi^'^lhoMgh this mode of prihting may have its ad-'
Tantages for some sorts of performance, where appearance can
be properly sacriticed to facility of execution, and tiie beauty to'
the cheapness of the article, we by no means think it carf be ap-
plied with success to the art in general. For, though we a^ie^
with the author of this paper that what '* the printed executes
with moveable types «/cjy also be pertornied by using stone," yet
only a very small degree of reflection will be necessary to con-,
vince any one, that it is- much easier to exfciife works of this
nature, according to the present method of settingj^ie letters, thanr-
it would be to draw them upon the sarface ef the stone. Betiide?
this, the present method is capable of a murb gteater degree of
accuracy than could be etlected by nsiflg stone; as any erroi!''
committed in setting the press, may easify be corrected when
moveable 'types are used ; but in printing of this kind with
stone, if any mistake took place in-drawing the letters ii must
he continued through the impression.
/■' 'l-JL
On that poxi'Ct of the Eye, by which it i$ adjusted to the Objects dis^
thict/y. at difcrcnt DUtar.ces, By Ez. >VALkErv, Esq»-^Phii.
Mag. No, i42.
»
Tins paper is a continuation of one which ve have already
noticed, vol. iv. p; 33, 308, and those who are -admirers of Mr.
Walker's former essays, will, without doubt, be equally satisfied
with this. 1. lie first observes, that the focal distance . of the
eye becomes in general larger as the age advances. 2. He says
that " those who have written on the properties of the human
eye inform us, that " if a good eye views an object at the least.
distance^ it can be seen distinctly, and then at twice that dis*
taoce^ and tbeii at an infinite distance, there 13 about the same
Mr. Walker on ihc Poker of the Eye! 14 1
siieration made in tbe^gur^ of tbe eye betweeii the two last*
^#ses, as there is between the two first;'' and having proceeded
to copy the demciostratioQ, be adds these remarkable words*'
^* Ilt^ce it Jbay be. deipt»n»trated« that objects at various dis-
tance may be seen distinctly without any alteiation in the hu«
piuurs of the eye^ 9T in ijts, otitw^rd form:^ and assuming fiomi
bis furhier paper, that ,^^ when' a good eye views an object at thd
l^st . distan<;e; it cuq be seen disiindtly, the rays which entet
ifae pupil are parallel^ or &uch as diflter veiy little froni'being
so," he finds no great diiliculiy in deducing his consequence^
from these premises. . 3. He describes the circle of dissipation
which is produced when an object is. viewed within the limits of
distinct vjsiou; and observes^ after Dr. Jurin, that other ^things
i>eing e^ualf, its , magnitude will .be proportional to that of the
pupil. 4» Mr. Walkcir quotes the ituthority of Dr: Matthew
YoMng^ who asiserts that^ a person, after having been couched,
could See oistioctly at diilbreot distances, and imagines that whefi
this power appears to have been lost, as in the case menCibiied by
Dr. Porterfield, the iris must have been injured in.th^ ppe^'atioti :
for he says, that ** it is a physical truth, which any one may
convince himself of by trJ^l, that wo mental exertion can change
the adjustment of the eye, when every part of the iris is co-
.^recL" 5. Mr, Adams's authority is adduced in contradiction to
tbe common, but erroneous opinion, that short-sighted persons ge^
/leraUy become less ^hort«.sighted as they advance in age. d. On
the whole, the author concludes, that the eye is a ' machine of a
•iixed and determinate fornn its only alteration consisting in the
dilatatioo &nd contraction of Che pupil.
•fa*i
Obs€rvations,-^^\Xe beg not to be considered As addressing anV
of the remarks which we shall make on this essay to the cozi^
sidenilion of Its author ; We arc conscious* of our utter inability tt>
afford him' any thing like information or iustrnction. If any
others of. our readers should entertain doubts on this subject, we
entreat them to take the trouble of making two pin boles, or nai*-
row slits, in a piece of thick writing-paper, at the distance of
about one tenth of an inch, and lookiifig through them b^ith at a.
fine black line drawn on paper^ held with one end nearly in con-
tact with the facBi aad^ if ^hey aro long-sighted, employing at
tbe same time their usual spectacles ; they will then see two
images of the line,.. crossing or meeting in the point of perfect
vision, and they will easily be able to judge whether or not that
point is stationary in all pcYssible conditions of the eye. We al^o
»sfer to p. X52 of our fifth volume, as well as to our accounts of
Mr. Walter's former papers^ for some further remarks on this
subject.
With. respect to the experiments being made ga persaiis wb»
' No. 24. — Vol. vi. ♦ . u
— • .' VJ!
142 Messrs. Mouclel on ike Manufacture vf Tron mid Steel Wire:
liave been deprived of the crystalline lens by an operation, I>r#
Thomas Yoiing has advanced many reasons for'believingy that
the faculties which such persims retain is that of sfifeing objects
iwith tolerable distinctness at different distances, but by nO'
means t)f actually changing the refractive powers of the eye. We
have evefc been iiifortned, but we will not vonch for the truth of
the fact, that sooie experiments have been lately made on the'
eyes of the same individual, who appeared, when examined by
Mr. Ramsden, Sir H. £ngle(ieldy and Mr. Home, to retain the
faculty of accommodation in great perfection after the operation ;
and that the eye, which had been deprived of the lens, appeared,
ivhen Mibjected to the more accurate teets which had been pro-
loosed by Dr. Yoniig, to be wholly without any power of changing'
its focal distance, while the perfect eye possessed it to a consider-
able extent Whatever the actual result of these experiments
may &ave been, we shtnild hope that an account of them wopkl
he laid befor6' the pnblid by some of the persons who were coir-
eerned in making them.
Note of a Discovery tf Mi*. Vacca, in Magnetmn.-^Phil. Magj
No. 142;
'' M^. Leopold Vacca has diHwered » fhelhod of commuai*
eating magnetism to a bar of iroif^ without ai nmgaet. .
** He tak^ a bar of iron oC about three feet in lengthy
which givej no ^ign of po^ssing any magnetic virtue, as lo*i%
as it lies in a horizontal position ; but it possesses this in a very
(sensible degree when j^laced perpenditolar. These sign^ . disap*
pear again whe^ it it is laid down horiisbntally,' ati^ appear again
when it is lifted vertica%w
^' A small bar of steel rubbed several thnes .in the satniii^
direction, against the extremity of the olhei* bar, wb^h situated:
vertically, acquires magnetism ; whence the' dkcottrer concluded
that magnetism may be communicated %& a body, without eitb«r
a natural or an artificial, magnet.'^
Obsertatiom, — Sboulid Mr. Leopdd'Vac^ continue his brilliani
eareer, with as much success as he has begun it, there is reason^
to expect that, in due course of time, he may diicwer that the'
earth revolves round its own axis in a day., and round the sun
in a year ; that lightning is electrical, and that water is com^-
posed of oxygen and hydrogen.
Extract from the Memoir of Messrs, MovcHEj^y of Vjiigkf in the^
Department de VOrne, on the MtmufaCture of Ircn and Sttei
Wire. Repertory ofjirtSf Nos. 95 and 96 f Second Series.
T91S is one a€ the most considerable manufactories of th\s
Mm^s\ Mnutiel miiheMmwfrdwnloflrmimdSied ^vru 148'
kind in France, and is said to produce a hondrcd thousaiul quin-
tab of iron .wire aiinually, in cards for \vobl*combing only. This
is chiefly cotosatned in France, and exported to Spain, Portugal,
ftaly, and the shores of the Levant It is necessary that
the atteniinrn of the mamifarturer, in the first instance, be
directed Itotihe choice of materials; and Messrs. Moucbel, after
trying a great many specimens,t liave adopted the iron- frooi
,the ^departments of I'Orne and Hau^e Saone, as being the best
adapted 'for the pjurpose. The first aifords the best wire fo^screw&i
nails, anjd pins ; but, by reason of its ductility, that of the fatter
^pactincat ca^ ha aia,|Ae (extremelj fine, and appears to be mmst
free from beierogencous particles. The inconvenience oi i>e?ng
obliged to use iron from ditferent smelting houses, was foand'to
be extremely prj^judicialto th4 uniformity u^d perfection Ireqtrired
in the delica^ pfig€e8.ses that are necessary in making iron wiie.
These manufacturers therefoi^ established a smelting house of
their ow)ii in the department, of ^aute Saoiie, wh^i>ce the prepared
iron i& conveyed by meana of rivers ainl canals^ at a ^nialt ex-
pense, tO! the maf^i^af tory at rAsgle*
Wh«». the iron has been formed into an irregalar hair of ab'oni'
sa cen^/mc/j-e ('39371 inches Ei^lisb) in diameter, they begiti'*
f» draw it into wira. For this purpose they first pass it four
times through the drawing plate. The fihTtfi which appeikf at the
utmost extension of the molecules that ale arranged Ijsngth-
waya^ are removed by heat, sttid the proc.ess fteain repeated threa
llOM^. Tl>e whole operation is thus repeated five times, and con-
sequently the wire is passe.d through fifteen numbers ; after whicb
n single heating ia sufficient to fift it to pass through six others,
sppd dl)en it is reduced to the thickness of a knitting needle. Steet
wire heiii|p naueh harder than that made of iron, requieee to be
passe4 thpough. for^'lour numbers, and to be annealed every se-
cond time. The wire is drawn with either the pincers or the
liobbin, which is a cylinder adapted to axle-trees. This last was
invented hyi th# grandfi^ther of Messrs. Mouchel, and is used Cq
prevent the marks occ<isiuned by the application of the pincers.
The degree of heat required in annealing the wire must be regu-
lated by the diameter; as upon this much of the perfection' of the
Aia&afaeture depends. When the wire is sufficiently stretched at
^ach heatingv it assumes a pecfuliar colour, which the workmen
•re careful to ahserve. ,
For anneaHag the wire, these manufacturers employ a large
elevated fiirnace, in which the wire is supported in the mid<ue
ef the flames on bars of cast iron. This furnace is capable of
containing seveft thoueand pounds weight of wire, so arranged^
that the thickest is exposed to the greatest heat; so that the
whole becomes equally heated in the same time. An incopve?
lupncei b6w9ver^ is exparieocfd with this furnace^ whieb leaves
* i.
■j^: •»■
144: Mes^ri.'Mauekel^on t^e Vcnuf fixture (^'Jtrmmid Sftrl fFirt^,
the heated wire exposed to the' atmospheric air, \vhich oecasions
both a copsi'derable loss of oxyd, and an expense in ren)ovii)g»t« Ip
o^der to pi event this» they have invented Uiiother'^rnaee, which-
]$ roundi and about one metre six decimetres, (near 5 feet
3 inches English,) in dlameier; and one metre e>gfat dceimetres '
(5 feet 10'80'78 inches) in height, exclusive of its parobolic arch
and chimney. The interior bt,iibis furnace is divided into three
l^rts ; |he fir«t receives tbe cinders ; the second is the (ire place ;
£^id the third receives the wire, which is pluced between two
cylinders, situated within each other, and'niade air tight.' 'Ihe
diameter' of the larger cylinder is about one metre r6ur centi-
metres (near ^5 inches,)* and that of the inner one about one
m^tre (3f).37 V inches;) and the fire circulates about the exterior
^rface of the former, and within the latter. > Several ;pairs-olk
cylinders are provided, in order that they may he changed
every hour, w)iich is eifected by means of a lever, thai enables
one man to draw them out or push tbeui in at pltsasure. These
cylinders ^rp not opened till soiiie time after >tbey are drawn
but of the fire, which prevents the oxidation that would
iplte 'plac^ if the atmospheric air was admitted while ' the wi*-e
4vas hot. Tl)is new furnacf is' more expensive than that which
was previpusly^ised^ hut its advantages more than counter balanco*
this expense, |i )S used for all wire intended for cards ; uHd the
large furnace for that of a larger and harder kind ;, but in >t)rtler to
diminish the formAtion of the o^xjd, tbe'bundles 6( wire, are dipped
into a (^uaiaity of wet clay, nnd then pat into tbb furnace, and*
auflfered io dry before the fire is lighted.
These authors make use of two sorts of drawing plates ; large
and small ; in the formation of which great care is necessary, as
much depends upon the ability with which this is' executed. The
method they employ for this purpose is to put pieces c^ iroit- of ^
proper size and qdnlity, into a furnace with cast steel, and inx.
crease the' beat until the latter is fused-; then the iron is taken,
out, and the ateel that adheres to it is amalgamated with it by
gentle blows. , *
It is then permitted to cool, and the same process repeated se*
veral times, till the plate has acquired its proper form and liSard*
ness. It is necessary that these plates should be of considerable
thickness; and the smallest used bv Messrs. Mouchel are at
least two centimetres ('TSri-S inches) in thickness.' Aiter the
vire has undergone the last operation in th^ workshop ol the
^ire drawer, and is reduced to the required degree of fme^cas, the
Smallest of which is stated at lQd,000 metres in length tb a chi-
Jiogram ; or 109,36'()-§- yards to 2lb. 3oc. 5dr. avoirdupois,
by means of the bobbin, it is subjected to the process oi' dre&-f
sage or straightening, which is esteemed the .most difhcult and
4eli6ate of all the operations, fty this it losejB the bend^or^ cur\<t
it had acquired on the bobbins. For the more i-eadily uuA
Messrs, MoufJtel on the Mdnvfactttre of Jim and Sf€^ IVirc. 145 .
effectually performipg this part of the manufacture, Uiese aittbor>
have also inverted apparatus for both straightening the wirey and ,
(ktcrmlniBg its suppleness. Ikit for a particular description of -
t{)ese» with other particulars, and a tabl^ oi the prices of the dif-
ferent sorts and sises of wi^e, we must refer to the }^ limbers of.
t^e Rq)er|4>a7 of Arts, mexitioned at the head of thi^ article, an4
the plate by which the memoir ^s accompanied. -
ObsrrTapions.-^Thost persons who are either engaged or iut^r
rested in manafac4.u)res of thi^ nature^ y^e conceive would be am-
ply repaid for their trouble of perusing thin n^emoir. It will be
^und. tQ c^oitbine ^ much greater degree of. scientific ingenuity,
i|^)d practical ,e:^perieuce.tlian are usually met with in similar esr
says, and the success with which t^ese have been exerted \ may.
^^ily b^inferred from th» tioeness of the wire produced. From
^e above statoment it appears that a ppuiul avoirdupois of the
smallest .wire contaips about 49)^53 yards. in :ledgtb. Now^ad^
slitting tlie sp^cjlic gravity of this wire to ht 7788, aa4a.pDupd
wnf coniamTrr-: cubic inches. Therefore .. ^ x r
f\^ * ' ' •
■zz 'OOOpOipSSlt) inches for the area of it# section |
/
' I ' ' '
'31^159897
and consequently^ '001593 ^or its diameter. . \ '^.
Another eirrumstiancip which confifms onr op'rnion relative to
the formation of the ((rawing |riates, is, that one of' these large
plalei reduces 1400 chiliograms, from the largest size to that of
No. 6, which is about the lhicknes« of a knitting needle ; and 4b'0
chiliograrns are also reduped from this size to the smallest carding'*
wire, by being passed twelve times successively through a single
small plate, -i'his we apprehend could not take place, unless they
were- very perfect.
p/i the Cortst ruction of T/uatres^ so as to render tlicm secure against
Fire, Bi/ Mr. B. Cook. JHth Remarks hy the . Cuuductor*—^
Phil, Jour n,' ^^c;. 11-^.
I^Fr, Cook commences this paper with a reference to a former
letter, in whicTi he recommendec^ the use of iron instead of wood
for the purposes of building ; and w^ich we have noticed at page
4-23 of our 6th yolupnc lie then offers some general observations
tending to shew the necessity of having, public buildings, and es-
pecially theatres, as secure as possible against fire: which he
says is to be effected by tlie use ^i iron, wherever it can be
adopted. Mr. C. then gives a brief description of ^vhat he deems
a practicable plan for a theatre, with a view of inducing those more
jiuppdiatcly concerned in the ereciion of buildings of this nature,
} 4p A/r.' Co^k on tie Comiruetwn (f Theatres.
t& give the slubjeet doe consideration. All upright and ijw^
supporters of the stage, h^ says, should he made of iron cast tight.
^ttcd and screwed together ; and to make the stage five proof
from beneath, projecting edges should be cast on the bottom of
each spar or joist, so tliat when fixed in their proper places for
supporting tbe ftoor, ti^es or quarries made thin, migh^ be laid
between the spars, thne Cbrming a solid fire-proof bottom. The-'
boards of the stage are then to be screwed to the spars, and the.
same principle acted upon throughout aU the rooms. Tlie doors
and stairs all to be made of iron in the manner previottsly recom*'
mended for other purposes, and as little woodf as possible intro^^
duced into any part of- the building ; by which means if a fire*
took place in any one part^ it could not readily comramicat*
to another. ' .....
If^e front of tl*e stage and tbe orchestra, should bt>tH*fte made*
nf iron, which 'w*)uW affotd an opportnmty <5f easily* m;akitig
tbem yery hfabdsonae. Jhe flttorof the pit being laid on arches,*
eouldnot be ilt any danger of fire ; and the seats, or al-l^ast all
the supporters of theoi as well as the framing of ,th£, V*^^
llhottld be iron. The front of the boxes being ca^i ki open work,
might be made very elegant. And jthe same mode of conktVuction
feeing keptup'through6ut, beauty and durability niigbrbe uoiteif
in a very high degree. ^
*' The roof should have no wood at all in it, but be qfuxpoeed
of hollow or solid iron, cast light, ^Md if each piece was *^raduate4
irom bottom to top» it would still make it more lights aQ.d yet be
equally strong. A roof of this description well secured t^ge*
iher with screws and bolts, &c.,. would not be considerably hea«>
vier than wood, as the iron would possess litrength equal to wood,
at less than half the thicMess."
Mr. Cook next enters into a comparison of the advantages and
disadvantages that might be expected to result from the use of
tbese twiodrlfrrcnt kinds ctf materials. The two t^iief objectieiisr
which could be urged against the adoption of iron in the way he
recommends, are conceived to be, difficulty oi execution, and ex-
pense of erectitm. With respect \o the f]rst of these, he thicks,
it is wholly devoid of foundation ; and that there would be no
difficulty in meeting with men competent to every part of the un,
dcrtaking : he also adds, " There would be, especially in a theatre,
the greatest scope for geniiiS'; thus migl^t be construicted the
most elegant one in the world ; and one, that no accident, no
misfortune, no incendiary could destroy : that would brave the
utmost efforts oftime.* With regard to tbe consideration of ex-
pense, Mr. C. tlinks that it would not deserve to be compared
with the durability, freedom ftom accidents, and the probability
of larger ^udijpnces which the adoption of iron would afford : even
admitting that the additional cost amounted to ten thousandi
Mr.CookmtheLoiOtruciifmifTheafrei. 147
jiouilds, it would be trifling when counterbalanced by thest aad
^be other advantages tbat would result from this mode of coiw
itruction.
The author of the remarks subjoined to this paper, after ad-
Vertir^ to vi hat has been said about the use of incooib^stible ma-
terials by Mr. Edgewortb and Sir George Cayley, (see page l6d
of our vol. V.,) obsjerves, that there is one great source of saving
which has not been taken into the account by writers on this
lubject ; and this he thinks has arisen from its anaotint not being
generally known : this is^ the saving of insurance. *' Tbe offices
were paid forty shillings for every hundred pounds insured, pre*
vious to the burning of Drury Lane Theatre; and since tht$
event, they will not insure at a^ less premium than foar guineas
pfer cent. Now the proprietors of the theatre lately erected»at
Covent Garden, state tbe expense of erecting it at 150, OOOl. ;
.the insurance of wbicli against fire, would- amount to ne has
than 6, 3001. a year, if, as 1 suppose, scenery and dresses be not
included in this e^tmate, the insurance would be still more to
cover tbe whole. And to insure only one third of this, or
. 50, OOOL, as on the old theatre^ the premium would be 2, |00l. sL
year.^ Would not the saving of sbcb a sum annually, more than
repay the additional expenditure for rendering the building proof
against fire by the general use of iron ?"
j^ . - '
Observations, — At the conclusion of our remarks oti the former
articles on this Subject, we observed, that the introduction of iron
instead of wood, where it could be conveniently uSed in buildings
of this kind, could not be. too strongly recommended ; and we
Uierefore fully agree with Mr. Cook in the greatest part of
bis communicatidii. We, however, cannot giv^ cfur assent to the
assertion, that a building chiefly composed of iron and store, (and
. such a one w'e understand Mr. C. to mean,) '* would brave tbe
utmost efforts of time ;" as all the objects with which wp are con-
stantly surroundtid, clearly demonstrate! that immutability does
' Hot belong to the ztsorke of man. But, without admitting this per«
petuity of existence, we conceive that the durability would bel
sufficiently extensive to warrant the experimen,t. Another cir-
cumstance which ought perhaps to operate more powerfully in fa<
TOur of the adoption of iron in buildings of this sort, is the great
saving Tn the expense of insurance, as estimated by the author of
the preceding remarks.
With a view of facilitating the computation of the compara-
tive expense of iron and wood used for the same purposes in
buildings, &c. it may be observed, tbat from a variety of experi-
• nnents stated by Mr. Banks, in his Treatise " on the Power of
Machines, &c.," it appears that cast iron is from 3| to 4\ times
. stronger than dry heart of oak of the same dimensions, and fron)
148 Mr, Cook on the Comirudion of Tkedtfcs.
5 to 64 times stronger tban deal. Of the different pieces of oalf
«ne iflch square, and onfi ioo\ lonn, upon which these experiments'
wer^ made, the worst, when placed in a horizontal position, and*
supported at both end«f, would bcAr 66O polurds, and the best ^7 A,
suspended from the middle; the arithmetical mean of whict> i^
817: but it will be safer not to estimate this at mbre than 800
in calculating tb* comparative strength of different pieces. The
weakest similar pieces of deal, just broke with a weight of 4^0',
and the strongest with 65O pounds : the meawof wbich is 57^ ;
but perhaps nk»re than 550 ought not ti> b^ used. The compa-
rative strength 6f any other piece consisting of similar materials'
may also be easily tixind by multiplying the breatith by the
square of the d^'pth, and dividing tW^ product by the length ; ail
the dimensions being takei^ in inches. Hvnce,' for A beam of tir
16 16et h>ng,< 6 inches broad, and 9 inches deep, which 'dtre the
dimensions ^xed by sfatute lor Londort ^fid its neighbotrhood/
t. 11 L 6 X S**, 6 X 6*4 .. • .
we shall have -7: =r -r^ n 2 =: Us comi^rative
16 X 12 lO X 12 ^
r x' 1*
strength : for the standard experiment this is -^ — f-12lh.
Therefore, as 1-1 2lh : ^ :: 556' : 13200 lbs. the actual*
streiigth of the given beam. See alsjo our tiftli volume, p. *?9.
Likewise!, iron being 6 ti rues as strong as deal, as stated above,
we have 550 X 6 zz 3300 Jlis. for the weight that would bi*e*ik
a bar of iron X inch square, and 1 foot in length. Now, in ovdcf
to find the dimensions of u similar irok bar of the same length'
8 4
;*s the d^ai beam, let x denote the breetdlhl then — ,r, or *• x will
. o 3
be its depth and, as - : (x X — x') -i- (I6 X 112) ; : 3300 :
x^ _ . _ _ J. . . /
1 3^00 or — : — - : : 3300 : 1 3200 ; from which x =: ^ */30
' . 4'
. 2= 3-301927 inches, thf breadth ; consequently - X 3-30197 =
4-4025()9 inches, the deptH of a beam of cast iron capable of bear-
ing an equal weight with one of deal of the same length, 6* inches
liruad and 8 inches deep. The solidity of the iron beam is evi-
dently 3-50l'927 X 4-4025()9 X 1^^ = 27^91 ciibic' inches,
nearly ; hc^nce, allowing 4 inches to a pouiid, its weight i^
nearly 6^S pounds.
The quantity of iron, however, ^piay He greatly diininisbed
xv'itlioiit decreasing its strength, by casting the beams hollow ;
as, when the sai^ie quantity of matter is retained, the strength
' o[ a tube is increased in a greater ratio tban that of the dm-
iriCter^. But to what extcnt^is mode of iBereosiog th^ str^iig^k
v''«.... , e
Mr. Cumbtrlanas Descnpiion ^7 wis, J^c, 14^
bf a tube with the same qufintity, or vrhai is still more to the
purpose, of retaining the sanie strength with a less quantity, can
be carried with advantage remains to be determined ; and we
regard experiment as the only sure test by which it can be
Ascertained. It wouid not, however, be difficult to calculate
fronj the principles stated aliove, the dimetisions of a hollow
rectangular iron beam capable of supporting the same weight,
with only half the quantity of iron ; hence its weight woali only
be 349 pounds, which would still add to its strength. The
same strength may also foe retAiined when cast solid, while the
weigi^t is decreased about ene third by making the edges para*
bolic, wheh circumstances will admit. The smaller parts, how-
ever, must be made solid ; and we ;ipprehend that some difli-
tulty would be encountered where ceiliiigs were required beneath
the Hoors supported by irod joists ; yet these would easiljf be
Overcome, and caniiOt be regarded «8 any formidable obetacie td
the adoption.
'-X-J — ILjL — ^ L-Ciij* — [■ Kjim-Lu LLUs^sssassmsas^
0
m
Jhols to dn'swer the purpose of FiU$ and cthet Jnstrumtfifs f&rra^
ruius uses ma(k of Stwie-uare. By G. Cumberland, Esq.
vsith Oil Anfiofntitm by fV. N.-^PhiL M<tg. No. 114.
Mr. Cmnberlah<i states^ that it was th^ expense flIHsitig ffotit
the wear of steel files which first induced him to think of the
present invention. In searching for a remedy for this inconve*
uience, it occurred to him, that, as onr stone^wure is so harcTas
to destroy files^ it might bfe used in the abrasion of s^.veral hard
substances. And relative to his mode of carrying this idea into
practice, he Observed j ** the first use I made of the suggestion
was to fold Up in muslin, cambrick, and Irish linen, separate
pieces of wet clay, fofcing them by the pressure of the hand into
the intefstices of the threads^ so as on divesting them of the
covering to receive a correct mould. These I had well* baked,
and immediately found I, had procured aft entire new species 6f
file, capable even of ^^estroyidg steel ; and very useful indeed in
tutting glass, polishing, and rasping wood^ ivory, and all sorts of
thetals.'' Ad iA all operations of abradings considerable manual
labour is req^ir^ in first forming the too!^ Mr. C. was induced
to think that his invcfition might be of no small importance in
the arts, both from thb ease with which they are forned, espe.
cisikly when a press is use^i for the purpose, and the ilrferiof va-
Ihe of the materitl of which thede tools are composed. He also'
5ugg6^ts their (ise for grinding speculufldfSy bdt not from expe-'
rience.
Alr< Nicholson, in bis annotation, thinks this ingenious hfvclta*
tion promises to be of considerable utility ; particularly in filiikg
Nu. 24. — Vol. vx. x ' ,
150 . Mr. Covgh on certain ^oficrtks ofSvlidi*
" ♦ * ... -
aud polishing a variety «( bard substances, citl)er witb or wiUv
nul ii fretting powder. He, however, conceives that many objec-
'tionsmaybe urged to their use in grinding sp.ecukuus, ** not
only w'i ill regard to the intended figure, but the naluie of the
nKiteridl." i
Olfsnraf ions. -^U Aooh of tliis nature be for.nd en a more,
extensive trial to answcf the purposes fcr whicl) they. are intend.
. ed, as well as (hoy appear to liave done with their inventor, there
can be no doubt that they will piove of considerable ^ri vice in
the arts ; though we think with Mr. N., that the griuding of
speculums is not one of the purposes to whleh .they will be.applu^d
with advantage.
Ah Inquiry, Gedmetricai and Arithmetical, into certain Properties f*f
Solids in generah and of the Jive rcvuhir Bod'is in particular^
By JoHK GouGH, Esq.^-'Phil. Juvrn. No. 115.
This paper consists of delinitions, axioms, propositions, ard
corollaries with their requisite denwnslrations : >wilh the first
three of which we shall present our mathematical readers, leaving
the demonstrations to be supplied,, and the corollaries inferred,
by their own ingenuity,
Deiinitions. — lit. An edge of a solid is a line terminated
bv two of its solid angles, and common to two of its adjoining
faces.
DeJ. Qnd, From PtippuSy lib. 5. Ordinate plane figures or
polygons are those vvhich are bounded by equal .right lines con-
taining equal angles.
V^f 3rd. Two or more plane figures are said to be of the same
<lenomination, when each and all of them are bounded by the
same nuniber of right hues.
Axio.MS.— Is^ Three plane surfaces cannot contain a solid.
Ax. '2nd, Any required solid may be cut out of a given solid.
Propositions. — Ist. J.et r, /, and i be the number of the
faces, solid angles, and edges of a solid, bourdt- il by polygons of
, the denomination ?i ; and let ;p denote the number of those poly-
gons, which hound each solid angle; of ihe body ; then we hav&
nc pt
*- 2 - 2- .. ' . '■_■
Prop, ^nd» If a solid angle be coi)taicied under p planes ; and a
solid angle be cut off by any plan^^ .the s<cljou Avill be a plane
bounded by\p right linesj^andp plane angles. . > .
Prop. 3rd, If a solid be bounded by surfaces of any kind, a«d.
Cf li Sy be tl>e number of its faces, ^olid ^^le$, and edge$ ; and
OM pf its 3oUd .angles be cut otT.by b, surface of any kind^ tlie
/,
rr
Dcsttfpt/dn of Mr. Prior'jiKHock Escd'pcfhcni. f^^
increment' of ^c '^together with thfe iticiemeAt of'i =::'tbe int'l*^
nientofs. :. i ■ . ' • v ' c-. .' - - .■ • >/
Prop, 4th,'l(i\ 55(i1id of any Ivind hav^any mimber of its salid
angles ciitiilf by asntuice'of iiirv kind, so';i?*to chantie UVe nuhV4
l)er of its laces : the nic'reiiK-nt t>l' x: toiiel'tiCr AviUi the kicrfetVierif
of ^ iz: the increnieiil of a*."""
Prof/-. t>fh\ f.et r, 1. 1 dttiole tlie"niih*i>j^> affaC'e**, s(»]id\ti>ycs,
and edges 'of any ^d\x\ whatever, tx^y(S we have the following: gen'e*
nil expression ; v -|- t — *''"2 n ^v. . ^ ' '. ' "' .'**'*"
Prwjo. €f/t. iWu solid bomidetl by poh-got^s of' t?he snnrle t5^nel^
minution ; put f: equ.il the numi)cr of iidrs ot'einh poh^i^'or?^
p rz the rimjLer- of polygoirs which' t(UJ(*h 'tac h " S(Uid itr»gU^?
then C rz -ip ~- ^p ~f i.\7" •— /r;?; ^ = -U '-^ '^i)) -f* Cn — h'p^^
s ~ 'l';//) -f. 5?/? -i- 1!;/ — ^ ;/y5 . •>'.:.•. v c -. 'i
yVr;;. 7^^'. 'ihe smu of the plane An<^ies- bmind'n^*. tlfe.-i^^
enisles of a re»;ular hody zr Hrp — i(vp •L-.'-^j/-^- ^iri -^^/^'t *' '^
• Ohsrrtntion s'.-^Oxif math^niaticAl 'readers Hrlll -recufffy 'pe^^i^lVtd
that this cominunica'ion of \lr. 'Gour^h is iot>feW u fef^tt-utafiV'S
than u nrnctiriil naliue ; 'aftd th'at it "hear.-^ evidt-nt murl^s'of i«*>ei
iiuily ni()t ti«\v()rLhy'of'ihe rq)ij"ti\tioi]'of its aiilhoi'. • ' ' '' ^
.t-
g-ii ■.,.■■- '■"".■i!'^ jp " ' ' ' ■■•i^.i^.i — " n-jj ■!*iii;ui.}"i;' uir'Ti.'v irr>
Vcsvriftmn.vf a:clock Escapeimnt, rmcfitedin/rMr. .•Q^os.gx. Puioa
J«//. l)'an\, JSoc^cti^ajyirtsiXdL XSil<'rl,
Int this escapement a s}5ring detent' Utc^^'s wj^uihst one of Uid
teeth of the swing wii-eel, and pre\eiits it fro:ii running dowo fj'ji
the action oftlie uiaintaininr; power, WhW'e anotii^^f Sj)ring deleni
<Mi the opposite side of the wheeP-vvhen left tit liberty unl(»cks this
former spring, by acting ngaii^t tlie end of a-small arc conmjcted
with it, and jeni«>ves it Iroiu the tooth of^tlie wheel against whi^Ji
it rests. In this contrivance it is necessary that the detent
spring, the impelling spiing, and the pendulum rod, all be fi.xed
to one C! ntrc, aiid thu hiLter spring ho so much stronger than i}j6
former thiU it may always be sufficient to unlock the wheel.
^Vhcn the pendulum moves towards the left hand, the impelling
spring unlocks the wheel, and a togth falls against the pallet
where it remains till the pendohtm returns to its former position.
** Then moving the impeHing spring, and the wheel being freej
ll>e weight oii its axis causes it to advuncie while it escapes one
tooth off the end of the pallet or spring; and Another tooth is
locked against tho detent spring, 'as before, while the pendultirii
returns, *and^ the impelling spring again unlocks the detent:- as
the impelling spring moves- towards the left, the resistance it
nieets with -from the elasticity of the detent spring in unlocking
ia returned to "It, so'that trbereis no nwre p'6<vcMost Ibairw^i
»»
14?^ Captain Pasle/$ Account ofthc^tnt^ Tdcgrafh
caused by the pressure of the wheel against the deteot spring, hj
vfhich means it is fr^() from the loss of maintaining power,
which is evident in all detached escape nrents \ have seen, bj the
pendulum or.crutch^ ht, touching a spring, or lifting a lever tq
regain the position for unlocking the wheel/'
■ 1 1 II ^mmmmmmt
0^««T<i^w«*.— Mr Prior states that " this escapement will d«
ibr a pendulum of any length, and the frictipn is sk* small that it
does not require any oil, for it may be made as little as the tooth .
pf tiie wheel can sufficiently touch the impelling spring, and yet
be properly scaped.-' The sopicty of arts appear also to enter-?
tain ^ high opinion of its utility^as their silver medal and twenty
five guineas were yote-d to Mr. Prior for his invention. We,
iiowfcvef, are by no means so sanguine in our expectations on the
•anie subject. It is evident from both Mr. Ps description awd '
the ^gure by which it is illustrated, that the impelling spring
must be of sufficient foice to overcome both the elasticity of the
IJ^tent spring ap<i |he friction of the tooth against its extremity :
and it ought to be remarkecl that ihe detent spring is removed
fron^ the tooth by a sliding motion, and \ve tbeiefore apprehend
not with so little friction as Mr. Prior seems to suppose. He
states that when the pendulum. an ives *^ at the perpendicular, it
meets the impelling, spring, and carries it along with it, until
the tooth of the wheil whicl} rests against it, escapes from the
^nd of it, and another tooth of the wheel conies to rest against
the spring detent. The succeeding vibration of the penduhim
sepeuts the same operation." Now as this united niotion of the
pendulum and the impelling spring is in a direction contrary to
that of the elastic tendency of the latter, we are wholly at a loss
to conceive how this motiop can be effected without considerably
checking tht vibrations of the penduluiii as th,e moving power.
Description of thi French Telegraphs used •« the Coast of Fhnders^
Sfc* with Observations on thp same, and a plan of a Fol^gravima^
tic Teicf^raph on a new construction. Bt/ Capt, C* \V. Pasley,
Xifthc Roi/al Engineers, Phil. Mag. No. 1 4.5,
TiJ£ French Telegraphs here described, consist each of an
upright post, having tliree arms attached ti^ it, all similar to each
other, and each moveable about a separate axis. One of tli^se
axes is near the head pi th|^ post ; and the disis^nce between the
centres of motion of these arms is rather less than double the
length of each arm* The high&st ot the three armd can exhibit
fieven distinct signals, but each of the others only six. The tota.^
number of combinations which can be made by these three arms
will, therefore, he three hundred and ninety oue» *' As onl v
/
Captam Pasle/^ Jccount of the Trmch TekgKf^pK ^^^
three bodies are employed iti the FVenrh Telegruph, it njay there-
fore appear saperior to the Admiralty TeUgr-aphs visetil in Kngl^ifid)
which by the combitiaticmof double that uuiiiber ot'bodies cao
only iTiuke sixty three distinct signais^'' '
Capt, Fu;>ley thinks that the iiiechaaism of tta^ French Teler
graphs was imperfect, or the niet) cmploy^^d in working tbet^
unskilful; as the signals weie made and repeated wjiii an vn.
laecessary loss of time. He observes that tbc^ arms ^vhich wer^
painted black and appeared like a solid siibstance at a distance,
are made like a Venetian blind, to diminish the action of the wind
in bad weather. Each arm ha» a counterpoise of thiii materials
painted white, which only becomes visible when the observer 19
near the telegiaph. When in use« each arm can be shown in a po«-
sition on each side of the post inclined to the horizon in an angle
' of about 4^ degrees, in a hoiizontal position, or at an elevaiiqa
jDf about 45 degrees above the horizon. The arm fixed near the
upper part of the post may also be seen vertically, which con^
stitutes its seventh position. Mr. P. was informed that the last
arm is not shown in the vertical position, and if so the numbef
of distinct signals will be reduced horn 391 to 312. From this
ilescriptiont it appears, that the French have adopted the priok
ipiple of motion employed by Capt. P. in h's nolygraminatic Tele*
graphs, with this difierence, that iiistead of fixing two arms on
the same centre of motion, they only make use of ^)no.
Jt 15 then stated, that instead of employing several posts as
jn Cai't.. P's former invention, a telegnph ot the same description
may be made with one post, since most of the signals are the
same in both casts, except in the. latter only the pair of arms at
the top of the post caQ be seen in their vertipai position, winch
4dimini&h«s the number of signals. He however thinks that a
telegraph upon this construction, would still be sufTiciently copious
jind powerful, and states that if four pair of arms were used, the
number of distinct conibinatic^ns would be 308,791 • If three
pair of arms were employed, the number would be i^,.9S5. And
if only two pair were made chtiice of, the number would' be reduced
to iiZ7' liven in this reduced state Capt. P. thinks that a
telegraph of this kind wou|d siill be superior to either those used
hy the French, or employed by the British Admiralty ; as the
signals would be equally distinct, and much more numerous. A
4lisadvantage attends the use of several posts arising from the
space they must occupy, in order to admit the motion of the
armSi but this space maybe reduced to about half, by* making
the posts of unequal lengths, so that each pair of adjacent arms
sxiay be exhibited above the other.
Obierv(ffumi.^^\\ii have already givcn,a description of Captain
.^ii^ley's former inventioa at page 6 of our 4th volume; and 4
! st Mr. Umbers MMod'offo>yfiyf^foncflrd i/rips, -S (*.
ivistorical sketch of all the pHncif>al inventions oh thesnhj^rt At
page 335 of our 5th volume.' We^'tl/Hik that the eh^p^otiuei^t oV
oee post -irtsteaLdofseyeratl; as atl/>p<ed by the Frenf h, an«d notfr
proposed by Capt. P. is an imj>n)ve'irient or at least a c()rlvenifn^e';
und we are also irtctiried to prefer the \3?<? of doublctit-tbal vf
single arms'.' By-comparhig •the-'descri)>6:oh coocaMicd wf tl>i*
arcicle, with that at p^ge 33? ^(A''*i'^\.Vi of thh' ii'Oikl''\t'\v\^
'readily be perceived that ibe-presVtiV'FrcHrh telegrai'hs ami Can?.
iPasley's are modifications of utyfwe^'invesited' by -i^f. C/f/r'pe ih
1793 This mode of-Capt, P'* is rerUii«?y iW<;«^iiious, a'n^^ a|>*
parenlly siipple, rut we conceive that it does'^not admit of hu(%.
n ready application to practic<i as he seem.? to 8Up[>oso; for ^
considerable dilficuUy and delaV' will arise indistiir^ifi'&hlng the
diOcrelU sigitals wlien i hey are tiiimeious. and' aisijMving fo each
4t8 proper number. ' As this incimi'enie.nce is avoUleii in Mnjof
L»€ Hardifa iiu'eritioo, di'scribed at page -^3 4- of our*.>th Volmii**,
^e think that i^\f of our readers, ftfter an accurate coro'pLirison of
the two. methods, will hesitate 10 'give the pVefer^ence to the
latter, • 1 -
'^mti^mtmm^f'^^mmjtm^fi ■><
Ai'cr.uiit of a Wit hod of d riving or forcing forward S/'tips 0/ ot/t(r
ViShil< bij tilt poucr if Stawuiiugtms, Jh/ Mr. Jauls Li^'a*-
KtR. licptrtori/ iff Jrtii» ]!^o. i^O", Second Scries.
This invention consists of two difierent methods adapted to
the same purpose of imptlling a vessel in any direction at pleasure.
The fh'fct of these is that of a^jiplyirg a. bucket, sirniKir to that
of a lifting pump, which is to be worked by any sufficient poAer
backwards and forwards in a tul>e or trunk, fixed to the vessf4
in the direction 'of its required motion, or nearly so. The vessel
is nioved forward by means of the bucket tfrawin:.' in tht* waier
at one end of the tube, and delivering it at the other end ; and
for this purpose the tube and bucket must be provided with
valves similar to those of a lilting pump.
The second method consists of an improvement on that in
whidi a forcing pump has been used. In thv present case the
water is drawn in by the piston of ihe pump in a direction p^^*
riillel, or nearly parallel, to the intended motion of the vess* f,
instead of perpendicular to it; but in a direction the reverse of
that of the recjuiied motion. By this means the effect of draw-
ing in the water is combined with tt at of forcing it out in the
moist favourabh^ direction for giring an impulse to the vessel to
be moved. ^ •
Any adequate powder may be used with ^either of these methods j
and neither this nor its c\ode of application Mr. Linakcr considers
as any part of his invention ; I^ut he thinks the steam-engine i&
O/t'tkcCo^iposiiion a/itl Decomposkion-^ Forces* 15^
^r^f.u^y: tjm ^e<:t,.p9Wer.U]at.<'ni) b^ applied. Mr. L. also states
thcii i^ ;^o<i>« «j(()eruu'^i>ts wLif^i hehns made ^vill] a heavy boat'
thiity <>iH* icet l(/oj:V, w.tb a single Uicket acting, *ii cording to the
fir«;t ot the two methods, and moved with a power ot eight n^en
U work it liv liie hand. ih8 in(HH)n of the bo4tt ^Tas at the rate
of 3i niikji per liour. lie inleis iVum what lie observed in,
these expt^rlme^ts, that a proper sea-going vehstl might be dri-
ven by a s»tea|u*engine at the rate of bix nules per bour«
Ol^rrx'afionx.^^We have alrf^ady stated onr opinion relative to
tye (»t)j'Ct to be eftVcied by lhi.>< contrivance, in our remarks on'
M( stirs. 'I'revaliick and l)i(k'.n>on's |)-.itent for machinery for the
f;u." piirpiise. See page l.Of) of vol. v. A steam-etigine is
di'emed tiir h<^sl firi-t mover in bolli methods, liiit respecting the'
best niLM|(- <»i"-iij)pl\ ini; it, there may he veiv iiiflVient opinions.
.Mr. L. \\\s iiUo out. lined a pat^nt fen* his invention, from the
^pecincation of which, part of the above coii.munication is an
exira'ct.
On tie drutposilim' end Duumty.fjs'ttioi) of Forces. Translated from
" 'IraitG eiementaire de ^ftati'jiie. Par Gaspard J\Io.\gk," by
J\/r. W. Maurat. PfhL Ma^. No, W:),
As this paper is of a geometrical nature, or.r vrant of phijtes
.necessarily prevents us Uom entering into particulars; we shall
thereiore confine ourselves to a brief statement of the introduc-
toiy remark?, axioms, and pn^posilions it lontains, and leave our
mathematical readers to snpplv the demonstrations for themselves.
When a force, applied to a deternuned point. of a solid body^
draws, or pushes this booy in any direction; the force may be
considered as if applied to any other point in the bodi/^ in the
same direction. The force may also he regarded as applied to
any oihei* point out of the imitf in the same direction ; piovidcd
ibis point he invariably attached to the body.
Whatever may be the numlver and direction of forces applied
at the same time, at thc.same p9int, there alvvuys exists a single
force wbkh cither can mdye or tends to move it in ti>€ same,
manner as all the forces togethe^r., .This single force is called the
re^lfufit, a^d the several for^res >vb.ich com])ose the system, aad
net together, are called composauts* 'J he operation by which
the r«sullant of several given c«m^posant forces is obtained is
called the Cmnposition of Forces, and that by which the compo-
sants are found ;wben the resultant is known is denominated
DccowpQsition of Forces,
. Mioms^-^ I . A point cannot ,910 ve .s^v^ral ways at once.
lis On the Compoitfion and DceowpesiHon oftarttti
2. Two eqi;al and opposite for^'es, applied at tfce same tirai?
t6 the same pdfnt, destroy each other's effects and are m equiUbrio :
and reciprocally, when two forces are i/i equilihriOf they arc e<|uat
and opposite.
3. \i several forces applied to the same point have all the
same direction, and all act the sanii; /vay, the cflfect produced
i» the same as would be produced by a single force equal to their
stim, acting the same way, and in the same direction ; tbis single
force is therefore the resultant.
Hence it follows, Jirstt that when two unequal and opposite^
forces are applied to the same point at the sao^e time, the re-
fiultat?t will be in the direction of the greater and equal to their
difference. And, sccondlif^ when several foices act upcm a point,
some in one direction, and the others in that Which is opposite ;
and the sum of those acting each way is obtained, the resultant
of all these forces is the ditlierence oi these sums, and i» directed
the same way as the greater.
PropoHitwtvi*^!, If to the. extremities of an inflexible right
line, two equal forces be applied, both of which act the same
way, and the directions of which are parallel to each other:
then \. Tlie resultant of these forces is parallel to them, and
passes thr^uu^h the middle of the right Ime. 2. The resultant is
equal to the sum of these two forcts.
2. If to the pxtremities of an inflexible right lin«i, two unequal
forces be applied, having parallel dirertions, and acting th^ samei
way ? 1. 'I'he resultant is equal to tbdir sum, and its direction ifs
parallel to that oi the forces. 2. The point at which the re^
su'tant is applied divides the right line int«> twoequdl parts which
are reciprocally proportional to the forces.
3. Any number of forces, the directions of which arc parallel,-
and which act the same way, being applied to diffefent points gi-
ven in position, and connected in an invariable iiiunner; to deter.^
mine the resultant ot all these forces*
4. Two forces applied to the same body cannot have a residtant,
unless their directions concur in the same point, and are con*
ti\ined in the same plane.
5. If the duections «f the two forces applied to two points of
the same body, are containrd in the same plane, and conftir jn a
certain point: I. The direction of the resultant of these forces
will pass through the point of concourse. 2. The direction of
fhe resultant \8 in the same plane as those of the two forces which
are its composants.
Lemma.-i^U a power be applied to the circumference of a circle^
moveable about its centre, ^n the direction of a tangent, itbas
the same tendency to turn the circle about the centre at tvbat.
ever point it be applied.
6. When the directions of two Ibree^s are ift tlie eame plane^
On th Con^fhUhn trnd^Decomposkhk offarpe^* 157
•anil concur in the ^ame point, if we take upon these directions
two right lines proportionul to the forced, and Complete tfi'*
parallelogram ; the direction of the resultant of these forces will
be that of the diagonal of the parallelogram.
7. When the directions ol t^<» forces are comprised iu the
^ame plane, and concdr ia the saine pointy if two lines be taken
as before, and the parallelogMm completed ; the resultant of
, these forces will be represented, in both quantity and direction, by
the diagonal of the parallelogram.
8. To determine the resultant of any number of forces, th^ direc-
tions of which, comprised or not comprised in the satne plane^
concur in the same point.
9. To determine the resultant of any ndmber of forces
Whose directions, comprised iu the same plane do not concur
in the ^ame point} whose points of application are connected
together in an invaLriable manner ; and whose magnitudes are
represented by given liOeSj situated in their directions.
10. If three forces have their nwignitudes and directions repre-"
sented by the three edges of a paratlelopipedori contiguous to
the same angle^ in such a way that the forces have the same
ratio to each other a$ these edges ; their resultant will be repre^
sented, both iti magnitude and direction, by the diagonal of
the parallelopipedoD contiguous to that angle.
Observations. — Siiich of olir mathematical readers ag ate either
iicquainted with the reputation of the author, or have ^een the
original work, will not need our recommendation of this article;
those, however who may not have had an opportunity of peru-
sing the original, will not cooceiva their time to have been ill
employed, in reading this translation. M. Molige has treated the
Subject in a satisfactory manner,. as far as he has carried it.
Which is far &om the extent of which it is susceptible. This subject
l)f statical equilibrium has also been treated at considerable length
in the first book <ni Dr. Gregory's Treatise of Mechanic* ; where
the analytical method is employed, and all the most, important
elementary propositionsconnected with the parallelogram of forces
with their dependent corollaries, are perspicuously demonstrated,
and compressed into a small Apace. Mr. Gough has likewise de*-
monstrated,- geometrically, some properties of parallelograms,
and shewn their application to the moments of forces, in an essay
published in the 6th number of ibe Mathematical Repository.
This, we apprehend, Ue did in conseqtience of not knowing that
it had previously been done by Motigt and Poinsot, Much in-
formation on this subject may also be obtained from the works
of other authors ; and we would particularly mention the treatises
on iriechanics by Legrange and Prony.
With regard to the different methods of deducing the primary
No. 24. — VOL. VI. T
15S On the Co7npo$ition and Decompontion of Forces.
))ropopa8ition concerning the parallelogram of forces, wc rady
embrace this opportunity of, observing that some authors have
commence4 their investigations by means of two equal, forces
acting ill parallel directions on a straight line ; others, by con-
sidering three equal forces as acting upon a material point, and
making angles of 120 degrees with each other ; while a third
method is that of two 'equal forces acting perpendicularly to each
other. Monge and Pvinsot have made use of the first of these
methods. The second, we believe, was first proposed by D'Alcm-
bertf in the Memoirs of the French Academy for 176.9. It was
simplified by Francccufy 'in his Mechanics ; and they have been
followed by Gregory, who has not only rendered the demonstra-
tion more concise, but also freed it from some objections which
might be urged against those given by the French authors. The
late Dr. BjobisoUy by ingeniously uniting the demonstrations of
Bernouilli, D*Alembert, and Frisi, has, in the article Dynamics,
Supp. Ency. Britan. deduced the same conclusion by a series of
dependent propositions, commencing with the case of two equal
forces acting at right angles to each other.
The den^pnstrations given by both Monge and Poinsot,
are simple and conclusive, if the principles upon which they rest
ran be admitted ; Poinsot's, however, we think, is entitled to
the preference. This method of commencing with equal and pa-
rallel forces, acting upon an inflexible right line, seems to be
objectionable, on the ground that it includes in it the property
of the straight lever; thence, involving a proposition, which
ought to be the subject of a subsequent investigation. It is there-
fore a retrograde step in logical arrangement, to infeK»the nature
.of statical equilibrium from the property of the lever, when the
latter- ought certainly to be preceded by the former. In our esti-
mation, the mode of commencing with the action of three equal
forces on a material point, the directions of which nrak^ equal an-
gles with each other, is the most simple and natural ; as it is not
only free from the objection which has been Urged against the pre^
ceding method,b \xi is also independent of any prior consideration,
and rests upon principles that may. be considered as axiomatical.
The case in which two equal forces are supposed to act upon a
-point at right angles to each other, is certainly not so obvious
a sourte of inference as that in which three equal forces are em.
ployed, in the manner last stated ; and therefore we are induced
to prefer the former. Other authors have derived the same con-
clusions, from the consideration of virtual velocities } but this
mo^de is strongly objectionable, on account of it8 involving ideas
that are foreign to the subject.
I
( 159 )
■HCH
J)acription of an Eye Bath^ to clear fhe Eye from extraneous Mai--
ters,.a/id to assht the Sight. Bit Mr, JoHs Duckett Koss.-r.
Tra?i. S0ciety of ^rtjf, VuLXXP^lI.
Tjiis apparatus conbists of a stand or pedestal supporting a
glass vessel, of either a globular or any other proper form. 'J'his
la,st has a neck at the lower end, and an apertujc at the top IQ
fit thie eye. The neck is cemented into a brass tube, screwed into
an ornamental piece of brass work, in the upper part of the pe-
destal. This tube contains a common pewter syringe, the end
of which is cemented into the neck of the glass vessel. " When
the instrument is used, the glass vessel is to be partly filled with
water, (or any other liquid with which the eye is to be syringed,)
so as to cover the orifice of the syringe ; tlie patient then places
[ his eye over the aperture in the glass vessel, and suddenly lifts
up the brass slider, to which the handle of the syringe is fixed, so
a? to force the liquor contained in the syringe through that in
the glass vessfcl into the eye; the liquor which covers the
point of the syringe takes otF the force with which the liquor
would be thrown into the eye, so as to render the operation not
in the least painful."
A more commodious but less ornamental form of the same
apparatus is made by soldering the syringe into a vessel of
japanned tin that contains the liquid, the globular glass being
laid loose on the top of it ; and the whole placed upon a table
-when used.
Observations ^-^We are always glad to notice the inventions of
! ingenious men, when their ingenuity has been directed to a prac-
i" ' tical object in which success must constitute a, general its well as
an individual benefit ; and this pleasure is more heightened in
proportion as success seems more certain, when this object
is more immediately connected with the particular pursuits
of the inventor. This is the case in the present instance.
Mr. Ross, being employed in the jewellery business, had fre-
quently suffered from extraneo\]s substances entering his eyes,
and therefore ei»deavoured to discover some means of relief under
such circumstances, when they occurred either to himself or
ethers ; and his success in the invention of this eye bath, is
attested by certificates from eight respectable gentlemen, whose
p-rofessional ability>or practical experience has enabled them to
think highly of the advantages that will result from Mr. R.*b
invention ; and the Society of Arts rewarded him with a pre-
im of fifteen guineas.
( m )
•mmeet
'ff^^mm
REVIEW OF SPECIFICATIONS OF PATENTS,
PPBtlSIIED IN THE REPEBTORT OF ARTS, HANCFACTURS8, Sc^^
During the Months of April, M/ry, and June, 1810.
Mr, JoiiK White's Patent for the Discoveryofa Substance ^capabk
of being converted into Statues^ artificial Stone, 4'6^ Dated No-
vember, ISOp. — Repertory of Arts, No/ 95, Second Series, .
Instead of the clay or other argillaceous earths dug out of
the ground and usually employed >" the; manufacture of the several
articles enumerated in the title of ^his specification, Mr. Whit^
hiakes use of the alluvial soil, or siltage, taken from the bed
of the River Tlianies, or from the creeks^ openings, iir cavities,
in its shores, into which the Waters of the river are suffered to
flow in London, and its vicinity, and within the flow of the tide.
By vavi()u8 experiments, Mr. VV« found this soil ." to consist for
the most part of argillaceous earth, clay, or chalk, and sahd from
the uplands, along with materials of the nature of pit-coal^ asbes^
sand,. and with the remains of organised matters." Sqch parts o^
this deposit are to be selected as are most free from worms, and
aquatic animals. These niatepali are then to be mixed with
such portions of natural clay or sand, oi either of them, as may
be deemed necessary, with a view of improving them and ren-
dering them more fit for the intended purposes; after which they
are to be made into the required articles by the usoal methods.
Observations. — -We should imagine that the novelty pointed out
in the specification of this patent, is by no means the most es-
sential part o? the manufacture t6 which it relates, the quality
and quantity of the materials to be mixed with the mud, as well
as the management of the mass, being prbbft^y of much moit
importance to the properties of the articles to be fabricated.
ST
Mr, Marc Isambard Brunel's Patent for cutting Fencers or
thin Boards by Machinery. Dated September, 1806". Repertory
of Arts, No. 95, Second Series,
. As Mr. Brunei's specification is accompanied with fi\'t figures,
four of which are very complicated, we cannot attempt any par-
ticular description of the machinery by which his object is to be
accomplished; and shall, therefore, only re;i)ark in general terms^,
that it consists of a plate, steel cutter or saw, put in motion by si
J
Mr, De Heinc\ Patent for Improvements on Prestes, l6l;
suitable power and apparatus, and of a platform upon which the
wo«d to hf rut is supported and moved. To effect this latter
purpose it is capable of being moved backward and forward
on the frame on which it rests, and also in a vertical direction
by means of four screws, that are used for effecting its elevation
or depreiuion proportionally to the thickness of the veoears to '
he cut.
Its general mode of operation is the following: The piece or
pieces of wood to be cut (for more than one may be cut at one
time,) are- fastened on the platform by means of cement or glue;
and the slider containing the cutter being put in motion, the work-
man attending the engine adjusts at first the platform to a ,
proper elevatioui propels the carriage on which it is supported
by the assistance of a* proper wheel, and guided by the apparent
jeffect of the cutter, continues to force on the carriage .till the
veneer is entirely separated. He then moves back the carriage
by means of the same whcpl, and prepares for another cut by
.elevating the platform to the thickness of the veneer required,
and then proceeds as before.
It is obvious that the cutter requires to be kept perfectly flat
and true, with respect to the propelling motion of the carnage
which supports the wood, and the motion of the slider in which
it is fixed, and also very sharp. For this purpose the inventor
'^as added to his engine a lap, upon which the cutter is to be
ground when necessary.
Ohservathns. '■^This apparatus appears to be well contrived for-
performing the operation for which it was intended ip a more
effectual manner than could be diine without some similar ma-
chinery. Ic is however, of rather a complicated nature, and
both its first cost, ^nd the expense of keeping it in repair will
be considerable.
1/r. AuGtrsTus.ftj^EDRRiCK De Heinf/s Patent for Tmprovemnits
on Printing and Stamping Presses, pated February 1810.— iif.
pertory of Arts, No, 96, Second Series.
In this improved method, instead of applying a screw for the
power, Mr. de Heine makes use of two sectors, or a sector and a
cylinder, or a sector and roller, to moveA)ne against the other, by
means of a single or compound lever. This lever is fixed into a
moveable spindle, the upper extremity of which is inserted in the
top of the press frame, and its lower extremity is cut into two op-
posite sectors with their convexity downwards. The lower end
bf the spindle works by a smaller part, in a hole in the centre of
'the piston head, and the upper end meets a screw in the frame by
l6t Mr, Mantons Vaicnlfor improved Thve^keepcrs,
which the degree of pressure is regulated. The V^ad of the pis-»
ton Is also cut into two convex parts, against which the sectors
of the spindle work when the lever is moved ; and cause the
piston to be compressed as in the use of the common screw, with
this difference, thai as the descent of the piston decreases in velo-r
city the power must increase in the same proportion. . This
spindle may also be applied to a fly press with very little varia-
tion. The sectors and the parts which come in contact with them
must be made of some hard substance ; the patentee prefers steel
or iron case hardened. The diameter of the moveable spindle,
and the snegs of the sector may be made of any size, according to
circumstances.
Observations. ^^Tht experiments of Ferguson and Coulomb have
proved that the least friction is generated when polished iron
moves upon brass ; we would therefore recommend that the con-
vex pa!;'ts (tf the spindle and piston which come in contact, should
be made of these metals, instead of iron or steel alone.
AV- JoHH Manton's Patent for improved Timemkeepers. Dated
December 1807. — Repertory of ArtSy No, 96, Second Series,
Mr. Manton's patent improvement consists of an instrun.ent
or machine for time-keepers to act in vacuo, and this is so con-
structed that they may be wound up without admitting the ex'ter-
nal air. The machine which is intended to preserve the time-
piece in vacuo, consists of a variety of parts, which tlie patentee
lias separately described by the assistance of a complex Hgure ;
we, however, shall not follow him through this description but
rnerely give a general idea of the whole in as few words as possi-
ble. The time-piece is properly supported above a circular plate
of brass made perfectly smooth, and a glass receiver placed over
it. To the low6r side of this plate, two stop cocks are attached
by means of screws ; one of these is connected vvith an air-pump,
for the purpose of producing a vacuum beneath the receiver ; and
the other has a barometrical gauge appended to it, in order to as-
certain the state of the vacuum in which the time-keeper keeps
time. An apparatus is also fixed to the under side of the plate,
by which the time piece can be wound up without adm tiing the
air to enter beneath the feceiver. When the necessary vacuum
has been obtained by means of the air pump, both it and the ba-
rometrical gauge are to be removed, and the other parts of the
apparatus are inclosed in a small box or case, surmounted by the
glass receiver.
The advantages of time-keepers going in vacuo, the patentee
©^serves, are, " The unusual pressure of the atmosphere will be
Mn. Thdf)ias<m*6 Put&ntfor Umbrellas and Parasols, 1 6$
prevented ; for when the air is heavy, the vibrations of the ba-
lance or pendulum are retarded ; when the air is light, they are
accelerated ;, but by these inventions of time-keepers going in va-
cua, the vibrations of the balance or pendulum 'will be more uni-
form ; the sea air, damps, and dust, which are so injurious in
rusting, corroding, and clogging the movements of time-keepers,
are totally excluded. The oil in vacuo will also be preserved^
ii a more uniform fluid state, and not so lia^ble to be glutinous as
when exposed to atmospheric influence. Great care should be
tdkeu to have a good air- pump, so as to exhaust the air as much
as possible ; for the more perfect the vacuum, the more correct
will be tfee motion of the balance or pendulum. These inventions
of tinae keepers to go in vacuo, and to be wound up in vacuo
when required without admitting the external air, will be of great
advantage in being applied to clocks and watches."
Observations. — There will doubtless be an advantage in keeping
tie works free from the contact with damp and other extraneous
matters, but we think it is not equally clear, whether or not this
advantage will be equivalent to the trouble and expense of oIj-
taining it according to the proposed method.- The apparatus isr
complicated, and several of its parts require to be made with .the
greatest care, in order to render them air-tight. The first ex-
pense of the apparatus, the attention necessary to keep it rn good
order, as well as the diflliculties in using it to persons unaccus-
tomed to things of this nature, will also be considerable. It may
also be observed, that even if the patentee were correct in his es-
timate of the naagnitude of the inconveniences which are avoided
by his construction, it would be much better to fill the receiver
containing the watch with nitrogen, then tjt) exhaust it, because
there would be less chance of error from the intiusion of the com-
mon air, in case of any accidAtal imperfection in the apparatus.
Mrs. Phillts Bowm Tiiomasok's Patent for Umbrellas and Para-
sols. Dated Aprils I8O9. — Repertory of Jrtsy No, 97; Second
scenes,
Mas. Thomason's invention is that of causing a part of the
walking stick or cane, the umbrageous part, the stretchers, and
other parts of the mechanism of the umbrella or parasol, to be
concealed or hid by tubes made to slide conveniently upon each
other, and which, when drawn to their greatest extent, cover the
above mentioned parts. When the umbrella or paiasol jg j-g.
quired to be expefflded, the tubes or cases are to be slided upon
each other towards the ferule, which gives the stretchers {y^ li-
berty to act and expand the umbrella or parasol. The< oyect of
l6A Mr, Schnudt*s Parent for a Phantasmagorie Chnmomeleti
this invention, tlrerefore, is to conceal the umbrella or paraiol utiT-
der the appearance of a walking stick or cane, when it is not re-
quired to be used. These tdbes are to be made of any kind of me-
tal, wood, ivory, or iuiy other substance that may be proper fot
the purpose.
Ohervafions.'-^lf the superiority in point of pnrtableness, which^
th^se umbrellas appear to possess, were compatible with a suffl-
ent degree of strength and durability, they would probably be very
extensively adopted.
Mr. JoiiK Schmidt's Vatent for a Phantasmagorie Chronometer or
^Nocturnal Dial, Dated Dectfnber ISOS.'^Repertory of Arts^
No, 97 y SccojkI Senes»
The exterior part of this apparatus consists of a vase or orna-
mental case of any suitable materials, so constructed as to allow*
a free communication of the air, yet to prevent the rays of light
from being visible, and having on one side a. watch with two'
dials, and on the other a glass or a combination of glasses fixed
in a, sliding tube. The diameter of this glass is an inch and three
4)uarterB, and the pins two inches and three quarters; its use 15
to represent tht nocturnal dial against the whII. A lamp i?
placed in the bottom of the vase, in such a manner as to be
capable of being either taken out or of having its position altered
with respect to the magnifier of the dial. The exterior diat
plate of the watch fixed in the side of the vase, is that of a
common time-piece ; but the inner one is made concave instead
of convex, and, as well as the hands, consists of any kind of
polished metal. Upon this plate the numbers representing the
hours are engraved in a reverse manner. It is a little inclinedf
towards the light and acts as a reflector to the light of the larnp^^
which renders it visible against the wall. This reflector or dial
is supported by an arm fixed upon one of the plites of the vratclK
A steel centre is fixed upon the cock, and carries two cylinders'
to which the hands, and the minute and hour wheels are attached:-
these wheels are double, namely, one on each side of ihe body
of the watch, and made to act in union with each other by a».
wheel and pinion.
Tlie mysterioi^s circulator, which the patentee states may-
be applied instead of the watch work above described^ or may be'
used as a separate time piece, or as an orrery/ Consists of the
work of a horizontal or vertical watch, fixed in a*l>Ox oi; globe re-'
presenting the earth. A weight is attached to the. hour hand
wheel, and the box with the watch aitd weight are fixed, to one
end of a lever, through Which a 9^el axis passes. The other
Wr. Le Caan*s Patent i& check the Action of Carriages. IbS
.ttid of the lever carries a box with a ^ufficieDt quantity of lead,
to counterbalance the watch io every position whcnJn motion,
and which is to be adjusted l?y trials, as difierent timepieces^
require different weights. The wboje of this apparatus resti"^
np'^n t^o jewelled fe.upp<»rters or fricti/)n rollers^ screwed upon ^
?tan(?, ujnm which is ^Iso fastened tVe support for'the rim, wl)icU
serves as a djaf upon which the hours anci mmutes are desciibed;
This rim maV ^e divided into 12 or 24 parts aecordipg to tlife[
constrnctiori of the time piece ; tlie 'hours and' miputes* are sbowii*
by one feand or.U^ or inskad of vvh^ch a* nonius' may be applied tO'
subdivide the minutes. ' ' '' ' ' '
' When this aj)|)aratus is to be used as a nocturnal dial, the
r^€ector above described is fixed lo t^e sfcel centre, and cbliBTiei^
withjp ^hc prnameataj c^se thtj^f ontaip^ the larnj^ an^ 4i>agaififtitj^
the hand showing Uijb ^lours is ^ikewi^e ^jved within ,tbe case.
Mr. Schmidt Las also invented a^j ypp^^ratys, to be fixed ^. the b^ck
©f the box containing the watch work, for ' representing the in-
crease and decrease, as well .as the regular reyolution of the moon
^>':nd tfie'carth :" This motion is effected by a small weight being
iixed to the axis Cf a pinion with 'six teeth, acfing into a wheel
with sa teeth. The axis of this last carries another pinion the'
teeth of which ,act upon a second wheel of 30 teeth, upon the
axis of which the bent arm that supports the mooii is'fixed. Tnia
apparatus, turning round with the box or globie po which it is
attached, causes thr wheel which supports the moon tiiQOve pne
tooth every day, ^ •/..... . . a , . >. #
<^crcatwrjft.'^\Ve are persuaded tbat all who read this apecK
fication with attention, will discover ihuch rno;e ingenuity than
trtility in the inventit^n which it records; and be inclined rather
to bestow upon it their approbation than favour it witb their
patronage. *' ' • '
"'■W —'■ 'Mm
BLWy^'ir-'TBICgBggEaBgBBI^BgiBgBgMgiP^
^ Mr. CjiARtf.s Le Caan's Pxitent for an Apparafui to duck thi
Actim of Carnages. Dated Februki-^, ^U<fi Hfpertdry of Arts.
J^o. 97 y Second Series. ' ' ^ T "^ *
This invention siijiiply consists in a bolt of imn ^xed to thu un-
te- side of the axletree of the ca rr^age capable of being b1 ided against
the nave of the wheel when it is required to stop itfrnotionf And
In order to effect this, two rings of cast iron are fastened to the
Iv'"'';'^ • *!^.*'^'^*'" projections or raised parts, against whicb
. the bolt IS driven when it is intended to lock the wheel of the
carriage. One of these rings is let into th« nave of the wheel
to steady and hold the other ^ght when the bolt* is driw
gainst it.
* * ;
l6S Mr, De Roche'i Patent for Jm^rwcments in BrewAfg^i
06scrrff/M?i?5-— ;-ThiB inventiop^ peems to be. o^ne that niay ihave
been .thought of by many persons previous to'!\Ir, LaCaan, but
given up in consequence ot' the disproportion which necessarily
tubsibts between the radius of the a^cletree or ev^en of the nave,
and that of the wheel. This ratio is frequently as great as that
<>f JOlb 1 ; and»therefore" the resistance occasioned by the friction
a the surface of the wheel will evidently be 10 times a$ great as at
tie bolt. Hence when the friction of the slidiog wheel is'^onsider*
fcble, either from the weight of the load br the nuiurc of the
ground, the axletree will be liable to injury from the operation
of buch a force exerted on the bolt.
I
'7_ ■ ' ■ ■ .. » ,. 1,.^ . .. .. I,. I ■iiii^ii
t« •
Mr. Ranpolfh TsCHrrFELi db Rocnvs'^ Pate fit for intprwe-
' ments *in th^ processes of Bre-xing.^ Dated September, iSup,
Repertory of A* is, No. 9^, Second Serits. '
The skins of pale dried malt are separated from it, and roasted
to a coffee colour. 42 lbs. of these skins by roasting are reduced
to about SI lbs. and will give a very fine colour to a quarter of
^It brewed into pprter; a smaller qnatitity oi roasted skins
give a paler colour, '
:' The roasted skins may either be mixed with the ground roalt
before it is bre\ved,'or they may be infused or boikd m the water
ind the liquid hltered, before il is used ; or tbej^ may be moistene<t
with water, and put into heer already brewed^ whi^l^ tjbey will ai
the game time clarify. . ...
Vinegar is to be made from ground malt, from.. which the skins
bave been previously separated : this vinegar will contain less
Essential oil than a.t present, because this oil resides in.theacro<»
spire ; this is taken away with the skins.
Malt wine will "possess the same advantage, and the spirit
distilled from wash brewed in this manner will be 'more neutral
or clinf er than -at presMit-;- - -^ '> « <
.The great difficulty is to prevent the ground malt from clotting
together; the a^ditioa of the roaete^ husks, or of the radicles di«
/nipishes tl^f adl^esion ; o|r the gr^tiind malt may be sifted into
the water, ' ' • . . . . i
Ob^erxations,''— The usu^\ method of colouring brown beer, when
jts colour is required to be deeper than can be communicated by
fijgh drying a portion of the malt, h hy means ot "burnt sugar,
j^ltbough the method proposed by Nir. de Rqche may at 4*"^^
Bight appear cheaper, yet as his colour does not contain any fer?
inentisscfble substance, we apprehQOCJ a larger proportion of tpalV
inust be vised to produce a beer of equal sireng^h ; and the diffi*
cntty oir madhing a farinaceuus powder will be a coosiikrablf
drawback* ^
< t$7 ■)•
Ja/-. John Fkederick Archbold's Patent for a metft^d f^ cmm
terliiig salt or aa wifter into fresh water ^ Dated Afrili 18u9w
. Repertory (f ArU^ No, gi, Second Series^ . . ......
. Tiie stiU is biing in a water bath etit of which 'there is no'
egress except hy a safety valve, by which means a stronger, degree
of heat can be cornuiuniicated to. the s.till, and kept up hy a small -
jSre. T1i% bottom of l\\t water bath ' may have a flue^ whicfa;"
imaking ^om^ .horizontal revolutions may pi^ss out into the ^
chimney ; the back of the fireplace may also he a rtarroty boUe^^ '
or if on shipboard, the chimney of the ^replace may be made to V
^sstbrotigh a vessel uptm the dee k, in order to supply warm
livater, hy iDenns of pipes and cocks, to \ht still aiid bath. From'-
the fleck of xh^ still, pipes are plated conducting the sieaxb int6 '
the cooking vessel*.
• • The range has two stidingdoors which cover the whole of it$
front, and slide forwards being supp<»rted by bolts ruiiping in '
v^ bt^ples 6x^ to the sides of ihe fireplace; so that these dibors '
either sliut up the fireplace entirely^ or serve as a screen when iC is
iiied for toisting^ ^
The steam tube may pAss througjh the si^ of Xhe ship, and
alon^ the outside, and then be brought in again, to ilischiirge the
condensed water ihtb the i-eceiver, ..,..'
Whed the sea water is distilled, it is passed through a tlUieV^
thus made« A cylinder of tin, oi other metal, is filled with
pounded charcoal^ and cjpsed at ^acii end by a perforated cover*
One end of thie cas^ is inserted into a cask also partly filled wit£i '
pounded charcoal, and thus the water being poured iiito ihe cask
fitters through tl^ case.
Ohservatioits — ^Tliis apparatus for distilling water by the inter-
iiiedium c»f a water bath niust of necessity waste more fuel thaii
if. the heat were applied immediately to the distiHing vessel.
JV/r. CiiARtrs VAL^NTiWi's PatetUjor a new wodt ^f ornaments
ing and. painting all kindle of japanned aud varnished xvarct.
Dated Mar'ck, ISO^. Repertory o/ Arts^ Nk 56, Second
Stries,
, Tub design which it is intended to trahsftr being ehgr^Ved'ijipoxi
four copper.plates, the sti^origest lights on the phite No. 1. arid '
•o' do sbceessively ttritil the darkest shades are engraved' upoia '
No; 4. Fine fan tissue or othei* soft paper is next prepared hf '
striking a brittle tool over ii with a very strorig sdlutiott of gnm
/
1 08 Mr. Vakntme^s Patent fsr Ornamenting Japanned Tfarts, SfK
Arabic, isinglass, of similar substaoce, in the proportion of aboat
k pound to a quart of water.
; The plate No. 4 is then charged with Frankfort black mixed
iip ^ith burnt h'nseed oil, and the darkest shade printed up6n the
prepared pstper rather wet; . The next pla[te is then charged with
the black \o which some flake white has been a(kied, and an im->
pression taken otf oh the already printed paper.- The back of the
pxint is then damped with a moist spunge,' and the plate No. 2
being charged with black to which a greater proportion of Aake
white hati been added, another impression is tak.eu. Lastly, the
oeepest iigh,ts are put in by charging plate No. I with flake
xvhite only, and passing the paper again through the press ; the
print is then left to dry thoroughly.
After this the back ground i^ to be mixed with (ropal var-
pish, and the whole of the shadows covered ArVith it evenly^ the
whole being left to harden for a day or two. The wm)d,« nietal,'
paper, or composition that is to receive tl>e impicssion is covered
Tifith a thin coat of copal vami^, and when it is so dry, that the
iipger wilLleave.a faint impression on the varnish, the prepared
impression is applied upon it| and gently' pres^sed down with a
Sponge filled with warm water ; keep the paper wet nntil the gumi
is dissolved, and then the paper may be easily washed away, and
when dry the waresr may be varnidhed and stoved as usual. /
^ . Other colours may be grouad with oilj and used in the sam^
manner.
If only a plain impression is required, the fan paper niay be
prepared with a weak solution of gum Arabic, of about a quarter
of a pound to a quart of water, and.an in^pr^ssion-^being taken
upon it, the printed side may be applied while wet to the varnishedi
surface of the substance prepared to receite it, and gently pressed
down with a moist sponge. After a few miuutes, the papei* aiay
be puVed off, and the impression will be left clear.
. When strokes are required to appear in jjold ODon any painted
sijrfacei it must first be gilded, and secured with copal varnish
left to dry quite h^rd. Then cover it with a Second cdut of*vai'uish,
$tnd when half dry, the impression taken o.T with printing iiik to
w^ich some virgin's wax has been added, is transfeired upon it as
just mentioned. This is then covered with the ground colour mixed
with varnish, and left to dry in the air. The substance beihg therf '
"warmed, and irubbed with cotton, the heat will liquify the ink and
wax, and thus the ground colour may be rubbed off, so that the gold
will be laid bare. Wood cuts are best adapted for this purpose.
, Engraved blocks may also be charged with gold size, and
printed upon the prepared paper, and by a moist sponge trans^ .
ferred upon any varnished body; when rather dry, the impression
iniay be gilt or bronzed. )
.. - Mr.. W'nrhurtonh F^€^tfor Detiot^UtnJf China\ ^a ' 16^
.. Obsec^aiions.-'^Much iogenuity has been exercised in this
Hi'ancb of manufacture in order to supercede the use of the penci}^
by stencilliag, caulking^ and prints fordied of small pieces of cork
or other elastic substance, but these improven>ents have not pro<
duced the full effect that was desired, as they did not traasfer^a
' painted or gilded surface upon japan wares.
. Mady attempts have indeed been made to produce the efiect of
painting by means uf.mea^sotinto printsl l*h^e were sometimes
applied in a way simihir to those on glass, by steeping them in
\^rm water, and care/uUy rubbing the pa{»er from it, bat the
enect was not equal to the trouble. Sometimes the printed paper-
itself was cemented to tbe jitpan wates,'but tlien thesb could not
be stoved in a suflicient heat to ensure their durability and
hardness without cockling the papev.
On the^ plan proposed by Mr* Valentine, and called by hini
poHzographic, the paper is caRen uway in an instant, and all the
colour discharged upon tbe wates< And although the process
may appear rutber tedious from the number of plates made use
ot, yet the effect which is produced, and which is nearly equal to
that of thti pencili amply repays the trouble.
VVaiuscoitings, walls, and ceilings of drawing rooms may thus
be ornamented in an elegant and expeditious manner. The prints
fiiay be u&ed the moment the back ground is dry^ or if they ar«
kept from the air, they may be applied with equal succesb many
mouths afterwards, and the paper taken away by the use of a wet
sponge, 'i he transferred painting itself^ A^^y^ when dry, be var«
hished and polished, so that its U'ue lustre and beauty will be
preserved for many ^ears4
Mr, pETtrt WAiiBtJAtON*s Patent for decorating ch'ma* porcelain^
carthniwahe and glass, with goid, silver, plaiina, or other metals.
Dated FcbhUari/y ISIO. Repertory of Arts, No, i)d, Second
Series.
TuiiRi methods are he re ^proposed. The first is, to fill an
engraved copper plate with oil, and print it upon a substance
composed of glue and isinglass; called by potters and printers a
batt ; this impression' iis then 'transferred to the earthen ware or
glass by pressure, and powdered gold, silver, oi^ piatina is laid .
Upon it, which adheres only to the impression.
In the second method^ the design is printed in oil upon sized
potters' paper, and transferred to the ware by means of flannel,'
w] other substance fitted for the purpose : the powdered metals
aie then laid on it.
The third is, to mix tbe powdered in^tals with oil, and after
mUng an engraved copper plate v/ithtbe mixture, to take tbe im<- i
{>res8ion upon si£ed potters' paper, and then tr49sfer. it tg XhP r
//
i*70: Messrs. Marshail and HayUr^s Pe^ifor' frtMufaAurtTi^ Sattl
ware h^ means o^ a rubben The paper is (hen taken off, leaviri^
the impression irpnn the ware.
The oils, batts, and powdered Tnelnls, Birt prepared by thi? uBoal
nethnds. wbiich are wfell knmvn in the trade.
Gold atid silver are best done in the first and sebond method,
for plaiiuH the third is best. Tbenl'etals are to be printed upon-
tbe glaze «f ibeeartben ware, and aT$ bnrnlid or buvnjsbed in ihe
(ftnie manner afa if they were l^id on with a pencil.
OhstTxatiws* All these methods seeiA to bfe'wefll adapted 16'
the purpose.
I
Messrs. JoiiW Ma Rill AH, 0nd John NAYLmV Patent Jor ma*
nufacturing and mnkinfr salt, Huteri February h lSOt>i Jtfper*
tory of Arts ^ No. 9?, Second Series*
Im the common method bf evaporating the brine, the fire ha^
access to the entire bottom of the boiler, btrt these patehtees
, propose to heat only wne or more spots of the boiler, and there-
fore, as tl*e other parts are not expos<td to fire, they may be mads
in the, form of shallow ponds of clay lined with tiles, or other
cheap materials; The circulation of the liquor })roduced by ebul-
lition will heat these places, and the ^a)t vlil be fornitfd into crys-
tals chiefly in tbe coolers or cond* nsiprs, as they denOriiinate the
parts not immediately heated by ti^e (ire.
OhservattQns. -^^The idea of having only otie part of a boiler
made proper for the immediate application of the lire. ^n<i forming
ahe other of cheaper muterials is a very old one.' (Uauber in bis
Philosophical furnaces, published nearly two cetitttries ago, ap*
'|»lied it to dislill^tion, uaing a barrel for the body of the still,'
hen ted by a hollow iron pear c<immunicatihg with the bottom of
the barrel; and for warm bathi* by a similar contiivance : froni
this arose the common propositioti of boiling meat by one
end ot' a guu barrel being inserted into the bStis'o'f the grate^'
and the othe# into a barrel of water standing before the f/re ; an
e?cperit1nent in which ,many wiseacres have failed" for want of
knowing that the gun barrel should Slant iipwards and be insertecf
tiaaLV tbe bo^ttom ol the cask. Werecolh»tt a stilk nearer approach
to* the present boilers' havihg been proposed for field breweries to
' follow an army, ih which the sathe wide wOodeh tub* was to serve
tis boiler, mash tub^ and cooler, a small part drily of its bottom'
bedng mad<; M' eoppei^ and intended to be^placed over a temporary
£te place.
It is doiibtful> whether the alternate heating anti cooHng of the
^rine will be favourable to the production of the salt considered "
>rjfya;xesp4(Ct'l9'ih« qaaiitiiy of «Jue2 that tntest be nseof; •
{ m >
ii;.ii',i'., I . ..,■
•
Q»..9 new Jiind,of JFufihn^ tehich twplaias^t he Formation of litApid
^l^.fir^t Qnly-thoterjDiiuerals • that bore ev'.deut marks ofthftif
ig{ieop9 <>rigiov j9i:^h »s Abfiidian, scariie, ^nd pttorice 6tob«f yr^pe
i^\$n}etf^^e4.ii» vok^aic pffoduoi^, • DeHinarest iii%t armnged th(r
V!BL§^UiUfjAuvergn«,»iiKnig.ti!«9e products ; but it was principally
Fjiujas ititnd Ddi^miett ..«hn detcrniitied cnncernnig cbeprodoctU^n
o( ^be^pMxifirak c«Utd-iby Dolotnieu,xom pact lava, -siDcd known by
ibe pan^ <if Irtboid iuva* -i be. me re adduion of tim lava to tb«
lis^ f)f ycdcanic lub^aacHS, ifl not Xh^ oivly discovery of con«fc*
^.u^iK^, for alihadgrb it Jiiail^undf jigone an o|»«rat.(>ri which is usti«
«|ly condifleftd AS beingt>f a disorgafiisiaf nature, it y^t cotit&ina
Vttbst^oces is th^. aame^sftatej and in ihe same disposition, as what
i^e contaified in tba xocka frovi whence it uas f;>rin^d. \Vh«nc«
U i^^caame.an objectof ioqaiffy .to determine how the substance^
tbflit formed tbe isasis.osf ibi& lava .were fnsed» anil yeu their tsu>tvy
ftppfMwrance rc4aiued;> and Ailsoto iix »poH ihe iiine ^hen ihecrys^
tak enclesed in porpkyxiiic lava w^re furlned. * *
Sijiesttce and Dolomatu endeavoured t<» discover a kind of fa^
si4n>^ia which the matter shouid not^lx^rfkiiiccid to'<gla«s or 8Cort%
but in vain. .J^pailansaaiii was eqaally tinsuccesstul. Ddtomieti
bOMKever, Was con^^inced irom bis observations, that earthy S4ib«
$|aoces. suiffrred in the deep lecesses oi the globe, froin some par*
iicuiar application of caloric, a kind oi fusion in which ihe sub*
stance act«d a|>on was only, disaggregated, but not ailered, and hft
iilso thought that the crystals tound in lithoid lava, preexisted* iit
it before its lit^efaetion. Ihis latte^ opinion tbund but f«w siip*
|)or.ters» ' *
• To obtain the proofs of this hypothesis, it was intended to en-
close pieces of roxk io^bedded in powder of the same, in crucibles^
to cover the mass with quartz powdttrtd, or other infusible subJ
stance, and ta expose the crucibles to a long continued, but mo.
derate beat. ihe. expentnents were already began, when Sii^
3ames Hall's essay on the efiects of heat ni(»diried by Confipi ession;
appeared; upon reading which, it vyas determined to make use of
the lights furnished by his experiments, in endeavouring to bring
tocktf to a kind of fusion, Biunlat to that by which litboid lav^
was formed.
An opfMJsite opinion, which altrtbuted the formation of Hth'nid
lava,, to (ievitritication, gained giound in the mean time; beifl^
supported by Sir Jame* Hall, Dai tigue^, b'leurijiu de iieJleviie,
fvnd Gregory Watts, in this system it was supoo^ed that hthoid
hkVH, arose from the gradual coolmg oi vitreous lava, or obsidfan :
thus entirely depaitiuu urom the system of Polumidii, who held
i
|72 Mr. De Dree <m ike Fvmiation rfUtkoid Lscti*
obsid^.an to be the produce of lithoid lava, whicb, on arriving k%
tlrt^ crater, and coining in contact with atmospheric air, defla-
grate^, and becan)e vitrified.
In order to determine whether lithoid lava was produced by' ft
particular kind of igneous fusion different from vitrificatioli, or
by devitrificatioiu the following experimenti tyere made on the
rocks. which appear to be the original matter of lava, and pAfti*
cnlarly on two kinds of porphyry, one with a ground oi trap, tb4
' other of petrosilex. The pieces of rook were^put into a poreelatn
case, or llessian crucible, imbedded in, and eort«red with'fhe pow«
der of the same rock, rammed as close as possible. T^hvip^wder
was then covered with a dake of niica, and the remak^der of the
vessel filled up with fine quartz sand; .Tbe porcelain cases were
then closed with stoppers luted by a very fusible glass, and pvj;
into a compressing apparatus. The crucibles were placed in-
other crucibles filled with fine quartz aand, and the cover luted hhi
with clay, and bound with iron, wine* P^rPonveCers were^Wi^tbin
tlie ipside of the cases or crucibles, except in the two first* expeJ
riments. The compressing apparatus wfts at first intended-tb'
prevent the escape of any gaisfous .fluids or to^ pt)e««ii\ aociMk/nft^;
but as it was found that very little gaseoua matter was e^mtainc'd
14^ the substances operated Hpoo, the apparatus was sinopMed,
and as no experiments are here rtelatied,. which ure afi«ctbd.l^.
f^ompression, it is usi^lesa to describe the Ap para tcm. ^
J, Greei* porphyry from Glromanv with crystals of greeilish
white felspar was exposed for 42 huurs, t6 a heat of about *lb d.
}kVedgvv. (as the pyrometers which were mrt placed in the hotiesf
pai-t indicated 14 d ;) the powdered stone was changed into a
bjack scoria, but the entire piece was net melted.
^. .Gray petrosijiceojus (felspathous) porphyry with iniletermi-*
nate crystals of white felspar, and grains of quartz, from the Py-
renees, was exposed to the same heat, at the same tiipe ; tbc
powder was only agglutinated, the whole piece was scarcely al-*
tered.
3. Serpentine porphyry, exposed for 18 hours, to a heat of 4
or 46 d., was melted into glass, except the included crystals of
felspar and quartz* ''^
4. Pyreueai) porphyry, same as No. 2, yielded a similar result.
" 5. Serpentine porphyry, same as No. 3, was melted into black
glass, except the felspar crystals, which were still lamellar, and
had not changed their form.
6. Another variety of serpentine porphyry, was perfectly liqui*
fwd, botl^the powder and entire piece.
8. Serpentine porphyry, same as No. 3, was exposed for 25 hours;
to a heat of 40 to 42 d. ; the powder was melted, and formed a
kind of&coria, not vitreous; the piece had been softened without
iieipg melted, and appeared like aemivitrified por^elaip^
AQr. De Dree on the Formation ofiithtnd Iavo. If 5
• 5- porphyry, same as No, 2 , with 1.1 grains of common salt^
iiiid 6q of 8ul)»hur .mixed wi^h the powder, was exposed as No. 8;
the licjuified .{>owder iiad the ap{>earance of jporcellanite lava; the
piece had been only softened.
i I. Green porphyry, same as No. ,6, in powder only, and takea
luddenly from Jthe iire, had become brick red, and was scarcely
agglutinated, except at the boitqiu, vvbere it was.bl^k.
12. 3 02. 4* dr. of the s^me porphyry, in powder only, and mixe^
with 9 grains of common salt, was exposed as the three forego-
ing ; and acquired th^e desired degree of liquefaction as the result
perfectly resembled lava.
i4. Another variety of serpentine porphyry, containing nodules
fi£ quartz surrounded with pyrites, was exposed for 36 hours to a
heat of 5f) d. ; the powder was melted^ and also the upper part of
the piece, where the powder had become a scoria.
17. Si-me porphyry as No. 14, was exposed to the heat of a
forge, about H2 to 133 d., for ^ haurs and a half ; the' large piece
was entirely melted^ and changed into a stone, in which the cry?
stals of felspar preserved their lainell^r jtissue.
19. Granite of Chamouni was oielted in the forge, but the
felspar and n^ica still retained their granitic disposition. .
21. Same porphyry as No. J 4, inclosed in junbaked porcelain,
was melted in the forge into glass, and run through thje numerous *
cracks of the vessel,
23. Same porphyry as No. 6, was melted in the forge, and
partly run through the cracked vessel > the felspar was melted af
well as the ground.
2^ Same porphyry as No. $,. gave the s^jx^e prodnc;t si» No. 21,
although taken on t b,efore it was cooled.
25. Same porphyry as No. 14, previously dried at a red heat,
wa^ exposed in unbaked porcelain t,o a heat of about $0 d. in a
porcelain furnace, for nearly 6 hours.^ the powder was liquefied
and consolidated into the lithoid state, but thie entire piece wa$
.only softened, anii had a porcellanous appearance.
26 Hornblendic rock, imbedded in previously ignited powder
of quartZy in the same heat, were liquciied ; som^e had run out of
the cracked vessel, what remainfd i^ the crucible was lithoid
Hi^here it was thick, hut res«mbl)?d scoria* where it was thin.
Several substances exposed in the porcelain furnace at Sevres.
in double crucibles, were completely vitritied ; the heat inde^a
wa 110 d.
33. Pyrenean porphyry* same as Ifo. 2, yielded in the above
furnace, perfect pbsidiaji, th^ crystals of qii^artz remaining m^-
jnelted.
57- A large mass of fissile uorphyritic rock with ' mica, im-
l^edded in powder of the same, m a crucible inclosed in another
ipf caist iron, the interstices being filled with sand; which covered
N9. 24.— .Vol, vu 2 a
17*6 Mr. Jbe tine dn ike PormHtion of lUioid iMtd.
taK This incipient crystallizBktiDii produced by the igtieonii h*
ftion IB perfectly distinct from the devitrilicatioo which succeedt
Id the titreous fusion, fbr the iirst ' is, as has been just said, a
ttier^ approximation of similar moleeules which have tiot ceased
^o exist ic the liquefied matter; the second is a new 'formation
cf substances- produced in the vitrified substance, all the parts of
which have beeu entirely cningWd together^ so that the new com-
pound never, resemblt^s ttbe origioal matter as it was before
fusion.
. The iithoid i^vas are.tho^ produced by the igneons ItqueEfaction
pra^^e/d by the he/at dit«|ig«^e4 l^y chemical. actions in the inte.'
rior of the earth, and communicated without combustion^ as al&9>
hy the caaipr<ession effected by the etormoos superiucnnbrnft
weight. The half meltni state of the interior of the earth, pro-
posed by Dplomieo^ is favourable to this hypothesis. The crys*
tals of felspar included in poi:ph>^ry are not altered- by the igneoitts
liquefaction of their ground, although that ground is . itself fel<<
Spathop;^^ they even resist the action of vitrification unless the
temperature is carried to a very great height. Whence it appears*
that the felspar, anaphigftne (leucite), pyroxerre (augiteX fttni other
volcanic gems, preexisted ip the lava before its fusion ^ but some
Crystals found in certain lithoid lavas must be excepted, as they^
may have been formed by the abovementioned incipient crystaW
)i£ation. > I'hey may be kr>f!wn by certain peculiar characters^
but the diffei'ence is not alivtfays easy to be discovered.
. At present the consequences of these experiments are coefincdf
to the fe»planatioR of the formation of lithoid lavas^ and the pre-
existence of the crystals found in lava ; but as lava itself ba9
considerable resembilancte to thet original rocks,, they might be ex«
|ended to primitive substanqes ; further experiments and obser^
i^atioBS .are howevj^r wanting. .
Sir James Hall^ who commenced^ bis experiments with calca*
reous spar, has made uae ^i them to confirm the geological
theory of Dr. Hutton, by, means of suppositions which he cotw
ceives t0 be possible. - It i^ astonishing that be has not distinctly
mentioned whether his results a«o$e from igneous liquefaction or
devitrification ; it is, however, most probable that (he lattei* is hi9
opinion, as it aigrees better wUh his vef^&rks on. the fusion of whin.*
stone in the Kdio* Trans, for 1799* But it &^em» more likely
that the. change of powdered chalk ipto '.gfanttlar marble was
]iy igneous liquefaction, than that the chalk was iirsi vitcifisd^
and then reduced to a hthoid state.
•«iW
Observatiansj^^An accoaal; of the expl^nmenti of Sir Jamer
Halli which paved the way for the above curious facts, was given
in our second volume, p. ^65 ; the present experiments are stitir
PM^ important as they seem lio shew that this kind-of JHOipie&t
Mr. Httuy on Arragomte. 177
'iksi0a UdLfs place at a iowe;^ temperature tliati has been hitherto^
supposed, and does not in lao&t casea require that compression
which had been c6iueived to be necessary. They aUo point out
the mode by which the experiments may be advantageously ex-
tended by persons who have at command furnaces in which a
moderate but long continued beat is kept up, as the necessary
apparatus is reduced to such simplicity as not to occasion any
great expence. To them, therefore, we recommend the prose-
cution of the inquiry, which is of the utmost consequence in
geology.
■w^ga^ttggggBB Willi I msasBsasB% ■ i i.ji.iii F"WTfmTiiBaeg
On jirragonite. By Mr. Hauy. — Jomm. des Mines, Ko, 136.^
The arragonitc is distinguishable from calcareous spar by its
hardness being very superior, and its specifii: gravity 2'9 instead
of ^'7i a^s also by its internal lustre, which is superior to that of
calcareous spar and approaches to timt of the diamond. Its
crystalhne forms are, as is well known, tery diiTerent from those
of calcareous spar ; audit exhibits only a single image of an
object m the same circumstancejs as calcareous spar exhibits a
double image ; and lastly, when arragonite i« exposed to the
llame of a wax taper, it is converted almost immediately' mto a
wt^ile powder, which is tbrown around the tlanac, by a kind of
cxplosi«)n, while caleareous spar remains unaltered, and preserves
its transparency for a long time. The imperfect varieties of
these, two substances do nut, however^ exhibit such striking diffe-
rences.
The concretions called flos ferri are probably varieties of arra-
gonite, as is also the hard carbonate of lime, described by Bour-
lioti as a distinct species, the primitive form of which he sup.^
posed to be a rhomboid of 128® and 64** ; but bard carbonate
has been divided in the direction of the diagonal of the prism of
128^, so that the angle appears to be an union of two angles of
64f° each, and thus its primitive form is shewn to be the same
i;eith that of tlie arragonite.
The soitnes of satin spar and its not being much altered by the
Aaxno.of a taper^ ^eetn to shew that it is a tariety of Ihe cotaoion
earbooate oi lime.
.if
OhservatiffnSi^^Tht differeiKes which are to be remarked be*
fweeti calcare<jus spar, and arragonite, fiotw ill. standing the iden-^
tity of their composition, as determined by the most able che-
mists, are so strikiug, that they cannot be considered in any
^ther light than as separate species. Hitherto arragonite ba»
been the oidy mineral which presented an anonialy in its crystal,
lisfttioe^ bui Qt tate anaXase w oisaoite has beeo^ found to have m
178 Mr, Hassenf/atz on pofiushcH Irdn»
different primitive form of its crystals from that of titan6 Oxide
or rutiie, although their composition is similar.
On Dusodiie, a new mineral .^nics, Rij Mr. ^01) Is Cordieu. —
Jouni. dcs Mines, No, \%.
This substance was found by D6lomieu, in Sicily, and brought
to Paris about ten years ago.
It i? compact, and found in ii regular masses which split with
the greatest ease into very thin leaves, which are very brittle, al-
tiiough slightly ^exihic. Its specific gravity is J*146. It is
easily cut. Its colour is gie^^nish gray, ^)r yeHowish gray ;
it is opake ; and it has a clayey smtll wheii niciisteiied by the
breath.
It easily takes fire, and burns with a clear flame, and an un*
supportrible stench like that exhaled by fetid limestones on ri>b-^
bing ; a sirtall piece is sufficient to poison the air of a room for
more thafi an hour* an earthy residuum of more ihan one third
oi the original weight is lett.
When it is soaked in water, the leaves separate, and become
not only tranalucid, but also perfectly ftexiblei
Dusodiie iies^ in a thin bed bttween two bedd of secondary
I'miestonc, at Mellili, near Syracuse. It has been h>ng known in
that country under tlie name of the foliated bituminous earth of
JSlellili, or by that of devil's dting ; but both these names being
improper,^ it may be called dusodiie, whose Greek 6tym^logy ex-
presses the fetidiiy c( its smell when burning.
Ohserratiom, — This bitu^minous substance most of course be
arranged after the species, coal ; it probably contains some sul,-
phuret, to which its horrid smell when on fue is owing.
On potashed Iron. Bj/ Mr. Hassenfratz — Jouru. des Mines^
Ao. 13/).
Gay-Lussac and 'Fhehard have decomposed potash b}^ mean^
of iron, and obtained alloys, which yield nitrate of potash when
treated with nitric acid. Now as iron ores are usually smelted
with charcoal which contains more or less potash, it is pfobable
that the alkali is reduced in the operation, and combined witlf
the iioB. Oak charcoal contains aoout 2 parts of salt in lOOO,
beach 5, elm 20, aspin d, in 2. Qua medium', lOOO parts of
charcoal contain 7 of salt, so that as 500 of charcoal ar« Usually
employed to smelt 100 of iron, 2 or 3 per cent of the new metal
ipav be combined witb the iron produced* 'i his sfmall ploportauri
Mr. Hassenfratz on poiasked Iron* 179
would not be of any consequence if it were not known that a
very minute portion of phosphorus renders iron coldshort, and
jninute portions of sulphur, or copper, redshort.
Tlie influence of potassium upon Iron has been uncertain, be-
cause the quantity of alloy , hitherto examined has been too
^mall to be forged. When coldsliort iron is purified at Zinswiller
(Lower Rhine) with lime and potash, it is rendered brittle if too
great a proportion of these additions zre used. ,
To examine the alloy of potassium and iron by experiments
made cpfr»n the ajloy itself, a gunbarrel was procured, in which
the above chemists had frequently repeated their process for re-
ducinj^ potash, and was still filled on the inside with pota^hed
iron. This gunbarrel was examined by a sawmaker, Roza, wljo
is usually employed to examine the specimens of iron and steel
sent to the board of mines.
The gunbarrel was heated, and flattened, in which operation a
piece of superpotashed iron was detached whicli was coldshort,
and when broke, seemed to consist of a mixture of a brown and
white raatf'r ; the latter had a metallic appearance, and ham-
mered easily, when it was separated from the brown substance.
In 24f hours time, this small piece was covered with the moisture
it had attracted from the air.
.The flattenqd gunbarrel was well forged, and spread^as easily
under the hammer as coldshort iron usually does ; it was bent
several times backward and forward without the least crack,
A small bar was bent several times in the cold, but at last it
})roke. Externally thi§ bar was dead white, like platina ; when
broke, it showed a white band with a very close grain which en-
veloped a brown nucleus, quite distinct, and only slightly adhe-
rent. I'his nucTcus was formed of white and 'brown grains
formed from that part of the barrel that bad bden most exposed
to the potash. The external iron was soft, and easily filed or
bammered in. the cold.
Another bar was heated to a cherry red and tempered ; the
tempered surface was blistered like steel, the metal had become
harder, but still preserved its njalleability, aii^did not crack till-
it had been bent several times. When broke, it had the same
appearance as before it was tempered.
It is, therefore, probable, that iron combines with two propor-
tions of potassium. One ad minimum, white like platina, easily
worked vvhether hot or cold, more malleable than iron, acquiring
hardness by tempering without becoming brittle as steel does;
whence it should seem, that the potash contained in charcoal has
a good effect up«n the iron which is smelted by its help. The
other, ad maximum, is brown mixed with white points, the par.
tides have but a slight cohesion, it is coldshort, and very pro-
bably brittle wheq heated.
}€0 hUssrt. Lussac aud Tkenatd on tke^mdah of Potash and Soda,
It is not, however tp be supposed that the properties of th0
alloy of potassium with iron can be rigorously determined by a
single experiment; new experiments must be made in order tn
determine the matter.
5B*
4
On the nmtaU of Potash and Soda. By Meisra* Ga v Lussac, and
Thenard. Journ, des Mifies, No, \^.
Some parts of this notice were inserted in our last nnmber,
p. 95» i^oya an extract published in the Annales de Chimie;
yit therefore omit thos« parts u4jich we have already given.
The quantity of hydrogen the metal of potash produces when
it is treated with water is erroneously stated in the Annales. In
the preseht pnper it is said that an iron tube was fiiled with
2*284 grammes of the metal, covered with a plate ofglass, and
thus introduced under a bell glass (jUed with water; aji soon as
the metal touched the water it was thrown up against the glass
hut no Hame appeared, and 648*92 centim. cubes of pure hy-
drogen were emitted.
The mi&tal of potash heated strongly with iron forms & soft
alloy. It also unites with quic)i silver, as soon as it comes
^ cont»ei therewith ; the consistence of th^ alloy varies accord-
ing to the quantity nf th« quicksilver. Both these alloys de-
compose ^ater'with more or less rapidity according to the greater
or less quantity of the new metal.
The oietal decomposes carbonic acid gas, and gaseous oxide of
carbone, yielding chaitroal and potash without any gaseous re-
siduum; nevertheless at a high ten^perature, the new metak can
))e obtained from the alkalies by means ef charcoal, for white
vapours are disengaged which have the same smell as the new
pietal ; but as nothing could be obtained except an effervescent
charcoal, it was concluded that the gaseous oxide of carbone de«
stroyed the new metal as it grew cold. Mr. Curadau, however,
has since shewn that the metal may be collected by presenting a
cold substance tp the vapours. In this process, however, very
iittle metal is obtained unless iron be added, or a gun barrel is
used, and the metal itself is rendered impure by the charcoal.
Manganese or sine might also be substituted for iron in the pr«.
paration of the new metal.
Four parts of metal of potash was heated with 5 of pure vitrified
boracic acid in a copper tube. No gas was emitted, and the metal
disappeared, being converted into an olive greenish gray sub-
stance, which did not effervesce either with water or the acids.
It contained borate of potash, with a great excess of alkali, and
an olivt coloured substance not soluble in water. The boracic
acid is probably decomposed in this operation.
/
Mr. Havy on Apopkyinte, 181
^Tien merrqrius dulcis was treated with phosphorus with
mlent to obtain dry muriatic acid, a liquid conipound was
jtrbtainedf strongly acid, colourless, and very limpid, which smoked
hy contact of the air. Blotting paper moistened with it took
fire of itself. This liquor grew thick in a few days, and deposiled
phosphorus. When it was passed through an ignited tube coik
iaiiiing iron, no other gas but a little uMiriatic acid was emittedi
and much muriate and phosphuret of iron *were obtainec|. It is
probable that tJiis compound may be formed by treating phos-
phorus with oxymuriatic acid gas, and that this is the reason
ihat phosphorus takes fire so well in that gas.
'J he inetal of soda i^ prepared in the same wiiy as that of
potash, and may be puriiied in the same manner. Its metallrc
trilliancy is very great, and its colour between that ol lead and
tin. It is ductile, and mav be kneaded like wax. It does not
take fire in the air, at 10 or 15^ nor when tlung upon water; but
it whirls about rapidly on the surface, becomes very hot, and
is changed into soda, twice as^ much hvdrdgen being dibengaged
as when the metal of potash is used. The metal of soda melts
' at 50°, while that of potash melts at 58°; when the two metals
are alloyed together tljey become more fusibje. Ihre* parts of
soda metal, and one of that Irom potash melts at 0^, but becomes
Jess fusible hy augmentinjg the proportion of the metal from soda,
and more fusible in contrary circumstances, to a certain limit.
The alloy of 10 parts of metal from potash, and 1 from soda is
not only liquid at 0^, but it also swims upon naphtha. In all
cases, if it melts at 0^, it becomes brittle wlien rendered solid by
cooling. The properties of these alloys explain why these
metals have been thought to be liquid when pure, unless it may
he that this liquidity drpeuded upon the greater or less quantity
of hydrogen that enters into the composition ol the metals of th«
alkalies, whicti is not unlikelv, as Davy has ob,tain.ed by the pile,
ii metal of potash fusible at 4^;
Observation f.-'^The latter pctjc «.. mis essay points out several
mistakes of Davy, in respect to the consistence of the metaU
obtained from the alkalies.
t '• ■ ■■ ■ m ,,r^tnt^rtr — mmm- " " "^M— W— — — — 1— i— — — ^^^^^^^^^
On Apophylliie. By Prof. R.J, IIauy. Journ.dts JUims, No. 137,
It shghtly scratches fluate of lime, and very sensibly carbonate
of lime. It is easily rendered electric by friction, and the elec.
tricity is that called the vitreous. Besides its characteristic
lustre it has a moderate degree of limpidity, without any peculiar
colodr. 'I'he fracture is conchoidal, and moderately brilliant.
No. 24.— TOL, yi. 2 p
1 S2 Mr^ UHalhy^ on the Tofniatwns of Flint Slate.
Observations, '^The remainder of tbis article is omitted, as it
may be found in Lucas's Tableau dcs Especes Minerales. Tw^
analyses o/ this stone, under its other name of icbthyophthalroitey
or hsh eye stone, may be found in our work. viz. vol. i. p. 376^
and vol. ii, p. 105.
On the formations in tikich Flint Slate is found. By Mr, J. J.
Omalius D'lLiLLOY. Journ. des AlineSy No, it>8.
Flint slate, or keisel-schiefer of Werner, is found abundantly
in the departments of the Ourthe, the Sartibre anci th** Meuse,and
in that of Jemappe, in three different depositions, which, howeverj
all appear to belong to a contemporary formation.
*■' The most remarkable deposition is of kidneys imbedded in bito-
miniterous limestone, in a manner similar to common flint in
beds of chalk": but th^ kidneys are cerierally mere round masses,
not tubefculated. The bituminoirs Timestone is usually covered
with a l)td of clay containing numeroifs fragments of the preceding
kidneys scattered through it, which seem to have been separated
from the calcareous beds by sonie accident.
In some of these kidneys the quartz veins which arc a strik-
ing character of the variety of flint slate, called I.ydian stone,
are disposed in concentric circles, as in some varieties of onyx.
' Flint slate also forms beds, and is then muchrtiore slaty, so
that it might at first be confounded with the black slate of coal
mines; but it is distinguishable by its hardness, its unfusibility,
and its not losing the black colour in the fire. The flint slate iii
these beds is very apt to acquire a grosser texture, and by this
means pass into the clay slate, or sandstone, which alternate witli
the beds of bituminous limestone, so that it is only in detached
places tlTat it preserved its proper characters in perfection.
Flintslate seems to be a variety of quartz. Brongniart has de-
scribed it under the name of '^lat}^ jasper, which appears very ap-
^licabte to that forming beds. Mr. Detbier, however; has found
in a quarry of black bituminous marble, kidneys of flint slate irf
hexaedral prisons terminated by a six sided pyramid. Thts&
crystals are the best formed in places where a mixture of clay
and sand renders the limestone soft and coarse grained • They
have the usual blackness and opacity, but their internal lustie is
bi*illiant and glassy, in these they come near to the quartz hyalin
of Hauy. So that in tact the same formation exhibits a series
'which passes imperceptibly from flintslate (quartz jaspe) in beds,
)iaviiig a dull aspect, through flint slate, (quartz agate) in kidneys?
y{\i\i a brilliant fracture, to quartz hyalin with a glassy aspect.
Mr. 1^Ut€r*i Experhntnts rdoiwe to Potash and Soda. 185
Vji af-tjficial Fuzzotana, or tarras. Bj/ Mr,^ G rati en Lepere.*
Juurn, de kliys. Apnl, 1 808.
Ba<;g£, of ^Oottenburgh, first eippIoy«d calcined argillaceous
Mones instead of tarras, ui the construction of tbelock^ on the ca-
nal of Tralhatta in Sweden. Many experiments have been made
in France, which show that slate cajcined, or other argillaceous
stones, when burned^ may be employed .instead of tarras, or
j>U22olana iit n^asonry under water, or for terracing the fii^ roofs
of buildings, and that tbe money sent out of a state for the pur<^
chase of these commodities may of course be kept at home.
•
Obsa-vations. — This is but one of those numerous political essays
which have lately appeared in France to encourage the use of
native articles in preference to foreign ones. The subject, howr
ever, is of some importance in the arts, and merits the attention
of speculators, who will certainly find it advantageous to bring
into the market, Engjlish tarriiS, at a low price. If, however, we
recollect right, Morveau has shown in a memoir upon mortar, &c.
(See Repertory of Arts, Ajc, vol. xv. p. 132.) That althougl^
these cements grow very hard in tbe air, they cannot be employed
under w;iter,.an assertion which is entirely contradic^ry to wba£
Mr. G. Lepere athrms to have taken place in his' experiments.
Experiments relative to Potash and Soda, Bj/ Mr, Ritter. Jounu
dk thysiquCj April, 1808.
TiiE several metals were tried as to their effects when used a$
the negative pole of the galvanic apparatus in the metallisation
of potash.
The me talloif substance of potash was obtained perfectly well,
and quite, pure wben platina, gold, silver, copper, brass, nickel
reduced per *e by Ricbter, cobalt, niccolane prepared by Richter,
antimony, chrome, brown suboxide of molybuene prepared from
molybdtnate of ammonia and which conducts galvanic electricity
as well as a metal, bismuth; tin, lead, 2iac, charcoal, and plum-
bago wer« employed. , , .
Arsenic produced the metalloid sul>stan'ce in blackish globules,
sometimes quite black.
, Crystallised oxide of mangajiese did not produce any metalloid,
but was itself disoxygenised.
Quicksilver globules placed in an excavation made in potash,
and connected with the apparatus by an iron wire from the
negative end, became thick, .and when separated from th«
184 Mr. Jxitttrs Expcrmeffti rilatke to Potash and SoJa.
potash, they grew solid: the quicksilver haying amalgamated witfi
the new fortued metalloid. If this experiment was so conductetf
as to moderate the heat, the amalgam tVeqnently crystallised upoiy
the potash, or at lea^t when separated from it, in cubical crystals,
which formed a kind of paste with the remaining unsaturated
amalgam ; thi? paste, after sonie time, became grca&y or rather
BOdpy to the feel. 'I his amalgam is slowly decomposed in oiJ
of olives, gas is emitted, soap is formed, and pure q«icksilvef is
left; bttt it may be preserved in naphtha, h does not detonate
with water, but yields a current of small bubbles -of hydrogen,
pure quicksilver is left, and the water continues caustic |)olash.
This amalgam is the easier to be procured because the potash
may be employed in a very moist state, by which c ire u instance
'the action of the pile is augmented. On putting the amalgam in
muriatic acid, although diluted, a very violent emission of hy-
drogen takes place, but no detonation, and muriate of potash is
obtained. In the open air, the amalgam becomes covered witU
a white powder, which deliquesces, and forms a solution of potash,
in which the quicksilver is left free and pure. It has at first no
action upon the tongue,, but the taste of potash soon becomes
apparent, and the emission of gas. If the amalgam is put into
diluted muriatic acid, in contact with a platina wire, the wire
yields much hydrogen, which shows that the amalgam is highly
positive in respect to platina, for plalina in contact with quick-
silver in the same acid do«»^ not produce any gas, and a very
small piece of amalgam in contact with {^ large quantity of quick-
ttilver in muriatic acid, causes t^n emission of gas from the whol6
surface of ihe quicksilver-
Water, or still better, muriatic acid, is an excellent method of
discovering the smallest quantity of' the metalloid in quicksilvf^r,-
hy reason oY the gas which they disengage.
Quicksilver that has been united with the new metalloid com.
bines more easily with platina, iron, or copper than before j
and these combinations are still more easily made, when the
metals that amalgamate with difficulty are used to foiirrthe com*
munication from the quicksilver to the negative pole of the pile-.-
In this Case the metal is dissolved in the quicksilver as fast as
the new metalloid substartce is Ibrmed; When arsenic is usedv
the amalgam adheies strongly with the metal, but so that it may
be separated by mere rubbing. The union of the quicksilver with
the new metalloid, does not depend upon the quicksilver combiu-
ing with the substance that forms the communication with ih6
pile, because it equally takes place when the communication is-
lormed by a piece of native oxide of manganese.
Tellurium being used as the negative pole of the pile, is the only
one of the metals that does not produce the new metalloid sub«
stance from potaslu The tell«rium loses its brilliancy, and is
Mk Rkiers Erptrimenh relative tb Potash and Soda, liS
H^isibly corroded; and a blackish brown substance is formed at tLe
place ol' contact between it and the potash. It is therefore pro-
bable, that tellurium attracts hydrogen more fi^rcibly than is don©
by potash, and that the blackish brown powder is the hydroguret'
of the metal. When the tellurium was placed under watt*r, op-
i^osite .a poesiiive platina wire, no hydrogen was disengaged, a
thick cH)iid of a flea brown colour was formed, and «^fterwajrds
deposil-ed ; tlie tellurium became dall, black and corroded as when
placed opon potash. I'his brown hydroguret of lellurium has a
strong cohmring. actie^n upon the skin. Telluriilm is thus the
only m^tal that absorbs all the. hydrogen that is formed at th^'
negative end of the pile. When it was employed as the positive
f»ole it cfto^ed all the oxygen formed from the water tt) be separated
in a g4$eo»s st^te, while the bnlUaiicy of the tellurium was not
affected in the leabt, in the same manner us when gold, platina^
or paUadium were nnployed : but 'nmie of these unite with the
hydrogen of tlte negative pole in so marked a manner. ^
Would it not be pt>$8ible to. separate the oxygen from water by
means of telliiiium? When that metal, however, was boiled in
di&tilled water no gas was disengaged, although it became dull,-
and coloured the hands and ,paper. Perhaps some of the new
metals fomui in eriidti platina resemble tellurium in theee qualities.
In geiwral the more oxidizable metals used a« the negative pole,
produce in equal time more of the metalloid from potash than
Ibe less oxidizable metals, or rather it is preserved the longestr
lor as the new substance is very highly positive in resp? ct to
the most oxidizuble metals, a galvanic chain is formed by the
new metaHoid, the wire and the moisture of the potash, which
determines the hydroguret of potash t*) oxidize itself faster than
it otherwise would, so that less of it is obtained. On a similar
analogy, when it is desired to precipitate metals by the pile from
their solutions, it is proper to use a wire made of a more oxidiz-
ahle metal, and it is even the best to ufee one of the same metal
as it is meant to precipitate* And for obtaining the metalloid
from potash, zinc, tin, or lead wire is preferable to those of
platina or gold ; iron wire is also very proper. If the pile is
very powerful, the new metal will combine with zinc or lead
during the operation, as with qiaicksilver, and these alloys appear
to have their melting point at a lower temperature than the
pure metals.
Seebeck, of Jena, is said to have discovered that all the
eartlis are as combustible by the pile as potash or soda, and that
the smell of barytes in combustion had a strong resemblance, to
that of potash when it detonates with water.
As yet no substances analogous to those procurable from
potash or soda have been obtained from barytes, strontian, or
lime> but the phenomena that deceived Mr. Seebeck are explan^ir
I^ Mr, Laugicrs Analj/su- qfScapolite, or Parant^lheJ
dble on the following grounds. 1. The great heat produced by
the pile ; 2. The heut emitted by those earths when moisteneJ
With water; 3. The different degree of solubility of those suh-
£fCances in water,- at different temperatures ; 4, The infiinimabilit^
of the hydrogen disengaged from the negative pole, and brought
about by the heat, and electric sparks that are* prodwced ; it
having been already shewn in ldo6, liow a drop of water may b6
> set on fire by the negative pole ; 5. And lastly, by the boiling
of the soldlion that is formed. Kven when potash or ^da ar^
used, several phenomena are observed, whieh appear at first to
Jinse from the decomposition of the metalloids, but which do not:
As to the odour said to arise from barytes in thes* operations, it
is owing to some of that earth which is carried up by th^ steam
of the boiling water, or by the hydrogen and oxygen that arfr
emitted by the two poles.
As the three earths here mentioned, are those \Vhich have the
greatest resemblance to the alkalies,- it ^as iiot thought neces^
sy.iy to examine the others at present, urttii str>onger piles cart be
procured.
It is probable, from some circumstances, that some new sub-'
Stances are formed at the j.ositiVe pole, from^pbtash and soda.
Obstrottiiom. — Wv, Davy has replied to some parts of this pa-
per, in his Bakerian lecture, just published in the Philosophical
Transactions for 1810, Part I. The bydrogexiisem'ent of tellui'
riura by the negative pole, streijgthetis the conjecture of the fo-
reign chemists, that the pretended metals from potash and soda
are really hydrogurets.
The deceptive appearances thiert ocCur when the earths are ex^
posed to the pile, are worthy of notice, and may have misled
Some English chemists, Ml the eageiTness of their chace after dis-
coveries.
W|PM— — ^^.i^Wji^w*.— WW.j»WW>WW^.^>—«ni^W ■» IMKIWWPI— ■»;i«>WT»l— — —
Analysis of ScapolltCy dr Patanthine, Bi/ Mr, La udiEU.—^ Jaw/7?'.
de P/ij/s. April, 1 808.
Ir contains 45 per cent of silica, 33 of aluinine, \7'6 of lime,
r of oxide of iron and manganese, 1*5 of soda, 0*5 of potash, aad
1-4 were losU
These constituent parts are very similar to those , of preh-
nite fix>m the Cape of Good Hope, as determined by Klaprothl
'X'he. specific, gravity of the two stones are neaily the saiue, that
of paranthiue being 274 and of prehnite 2*69.
< ifiT-v )
Pn the Chabasie, or cubic Zeolite^ of the Island of leroc, Bt; Mr,
Vauquelin. — Journ. de Phj/s. May, 1808.
Tins stone received its present name from Bosc D' Antic^
,who first described il in an essay 'sent to the Society of Natural
History, at Paris, Rome de Lisle considered it as a kind of zeo-
lite.
It contains 43*33 per cent of silica, 22*06 6f alumine, 33*4 of
lime, 9*34, or perhaps more, of soda mixed vi}th potash, and 21
of water, besides some traces of iron and manganese, which per-
haps arise frorii the mixture of some particles of the lava in
which it is found.
It is probable that chabasie is attacked by acids, and forms a
jelly with them ; but the quantity at command did not allow of
any further experimei^ts.
^^*n«(Wn
Q;i the Properties of the nexp Allaline MettU* Btf F. R. Cu-
VLA.\JX>AV4'^Journ, de PA^s, June» \S0$,
Several of the plieoomena that accotppany the metallizatioii
of potash and soda cannot be explained upon the supposition that
the alkalies are merely disoxyg^nis^d ; neither will this theory
agree with the properties of oxygen or of jv«nmonia.
These researches are the more intej-estipg to the author, be-
<;ause the results of the experiments published by him in the year
10, announced the decomposition of the alkalies, and might in^
deed have led to the prediction uf tbieir being capable of metalli-
zation.
, In- respect to the m^feal^ of the alkalies containing carbone as
cin essential ingredient, the two following experiments sedm deci"
sive. ,
Silica heated in a glass tube with the alkaline metal, combines
with^the alkali, and the carbone is left free, and can only be burn-d
by heating it with access of nir.
Secondly, a piece of the metal of soda being wrapped up in
some sheet lead, and immerged in hme watei^, the metal was oxi^
^ized, and carbonic acid was formed.
From these experiments it follows, that the attraction of the
alkaline metals for oxygen, is a delusive appearance, occasioned
by the presence of carbone. That carbone may be obtained fjon^
these metals. That the lightness of the alkaline metals, is pro-
bably owing to hydrogen being also combined with the alkalies
$^ these reductions. And lastly, that the various trials wli^ich
f S8 Mr. Sage on the Exhtencc of Alunilne in Stones.
.are made for disoxygenising different sul)slances by means of the
alkaline metals will always give equivocai results as l<mg as any
of the elements of these singnlar substances remain unkuowh.
0/»5e;Tff^io«5.— The caibone which appears from the above ex-
periments to have been present in the alkaline meuls prepared
by Mr. Curaudau, was, no doubt, an accidental impurity. The
experiments themselves are very iniporfictly related, as not ihe
least attempt seems to Lave been nuide to measure the (Quantity
of the products. We learn however from tlieni, that the metals
of the alkahes ran be combined wilh caibooe ; unle^&s it should
rather be thought, that the traces of that principle proceeded
^rom the ether, oi more probably oil, by which the metals had
been defended from tlie air.
SR
Description of a Process for detennining the Existence of A famine in
■ the Stones which haxe falltn upon the Earth* By Mr, B. G* Sage.
Joum. de Vhysique, June, 1808.
.Margraft and Bayen analysed stones by the action of sul-
phuric acid, because they knew that fusion with the alkalies al-
!tered the nature of the earths ; and this appears to be certain,
because the most celebrated chenriists, as Klaproth, Fourcroy,
Yauquelili, have not made any mention of atumine. Whereas on
on examining the sto;»<?s that fell at L'Aigle, and Salles, near
Ville Franche in the Lyonnois, by means of sulphuric acid, one
fourth part of alum was obtained from the formei stone, and one
eighth from the latter.
The stone that fell at Salles was powdered, except one eighth
that resisted the pestle, and being melted with borax, yielded iron,
which, when passed through the rollers, was as bright as the
finest steel. The powder, weighing 18 assay cwts., was distilled
with an equal wei«ht of concentrated sulphuric acid, and yielded
sulphurous acid with one 30Lh of sulphur. The residuum being
'^•lixiviated, yielded crystals of sulphate of magnesia, or Kpsom
salt, and alum tinged green with nickel and iron. As the resi-
duum was not exhausted, it was distilled again twice with fresh
Sulphuric acid, until 9 assay cwts. of very white silica or finely
divided quartz were left. The ley of each residtnim was heated
separately ; that of the first distillation contained much sulphate
of magnesia, and but little alum-; that of the second and third
contained more of the latter salt. On analysing the stone that
fell at L'Aigle, all the leys were added together, and yielded on
evaporation, first alum, and afterwards sulphate of magnesia.
The proportion of magnesia and alumine appears to vary in
Mr, Cadet on the UnxvhaksbmenessofTed* 189
t)5^se stones, but»silica or quartz appears always to constitute one
half of llif ill, and sulphur abput one 30th Dart.
The existence of alum in lhej>e stones is thus shewn, by the
same inrtms as it was discovered in hornblande ; and therefore it
vs evidently necessary that minerals should beexammed by treat*
ment with sulphuric arid.
Tlje silica usually cited as a constituent part of stones, may, in
many cases, be only the product of igneous salts with ba?is of
hatron decomposed by the potash havinga stronger atiinity witht
the acids than natron has with them.
As the brilliancy of the metallic iron contained in these mete-
oric stones d^d not appear to advantage in their fracture, it was
tried to turn a cup out of that which fell at Salles, but it chipped
%o much, that recourse' was obliged to be had to the file, and fric-
tion upon a eastr iron plate, sprinkled with sand and emery. On
polibhmg this cup with emery and Veiaetian trjpoli without
water, for fear of rifsting the iron, the sUmc exhibited irregular
spotij of a silvety whiteness, intertnixed with very small greenish
yellow spots, disseminated through an ash gray quartzose mass.
Obser sat ions. — The treatment of minerals \^ith sulphuric acid,
has been often practised, and in respect to aluminous and raagoe-
sian stones, which are not so well prepared by ignition with pot-
ash, as the siliceous, it seems to havie some advantages; but the
fusion of the aluminous stones with borax, which acts upon theiri
in a very elBcacious manner, requires less apparatus and less
time.
r^n
.—/
On the Unxbholesomeness of Tea. Bf/ Mr. C. T.. Cadet. — Jourm
(le Physic[uey June^ 1 80S.
Tea before it is dri^d, is of a more or lass deep fine gre^n co-
lour ; its taste is bitter and &tiptic. 1 he teas that are sold, vary
in tlitjir appearance, as some have passed through boiling water,
and others are only dried. In general, imperial tea is deep green,
green tea is puce green, hyson is blueish green, bohea is yellow-
ish green, peko is almost black, gunpowder tea is grayish green,
souchong is reddish. The odour of tea is equally various, and
does not belong to th6 plant itself, being communicated to it by
other aromatic plants^ as chlorantbus, olea fragiaus, commelina,
sesaaqua, Arabian jasmine, and curcuma ; besides Florentine ox*
ris. which the retailers put at the bottom of their canisters.
The infusion of tea mad6 at 70^ or 80°; which is the most
usual heat, does not redden infusion of litmus. Mineral acids en-
liven the colour when they are dilute, and destroy it when the/
^'o. 24. — Vol. vi. 2 c
IpO Mr* Cadet on the Vn-ohoUsoineness of Tea.
are concentrated. Alkalies turn it brown. It precipitates txlU
phate of iron black, and it coagulates a solution of glue.
Decoction of tea has the same properties, and also Jets fall mu-
cilage, on alkohol being added to it. \Vhen the decoction is very
strong, it dyes woollen, by the help -of a mordant, of a good nan'^
keen colour.
A tincture of tea made with alkohol, yields ink with sulphate'
of iroE, and contains a large quantity of resin mixed with extrac-
tive matter. Half an ounce of tea, yielded a drachm and a hal^
of resinous 'extract. This tincture dves silk of a fawn colour.
Tea appears to contain extractive matter, mucilage, a laige
proportion of resin, gailic acid, and tannin. I'he two last prin-
ciples explain the febrifuge quality assigned to tea by some me*
dical men. It is not necessary to mention the fixed principles of
tea. When, however, the leaves of tea which had been infused,
were dried and burned at the flame of a candle, the edge of the flame
was tinged of a green colour ; nevertheless the niost accurate trial?
could not discover the least trace of copper, either, in the leaves
or in iheir ashes: there were only found charcoal, iron, and mu-
riate of alumine, but no potash, so that if any copper be present,
it must be too small a proportion to be hurtful.
Superfine hyson contains the greatest quantity of gallic acid;
then gunpowder tea, pouchong, souchong, imperial, hysonsekin,
green, tokai, peko, and lastly bohea.
Superfine hyson also contains most tannin, then gunpowder tea,
imperial, and seuchong ; the other sorts do not contain any.
Superfine hyson is most abundant in resin, then imperial, gun*
powder tea, souchong, hysonsekin, green, tokai, poucliong, peko,-
and lastly bohea.
Peko contains most mucilage,, then pouchong, hysonsekin,
green, lastly tokai and the other kinds.
Superfine hyson contains most extractive matter, then imperial
gunpowder tea, souchong, hysonsekin, green, tokai, pouchong,-
peko, and lastly bohea.
Hence it appears that the teas which are most carefully pre-
pared, contain most of the astringent and resinous principles, and"
as these teas are carefully roasted, it is probable that the roasting
developes these principles. Bohea and peko, which are gathered
in May, and have probably been infused in water before they
, were dried and rolled, contain very little astringent matter ; but
the peko contains so much mucilage, that its decoction draws out
hi threads, like that of linseed.
Again, for a styptic and astringent drink, hyson o** gunpowder
tea must be used ; for a slight tonic without any astringency,.
green tea, or tokai ; for an emollient and detersive, bohea or
peko.
Mn Curaudau*s Experiments on Sulphur ^ ire. 1 $ I
^he leaves of lea when fresh gathered, are of a very disagree*
Able bitterness ; and have so strong an action upon the nervous
system, that they even occasion deiirium ; but the preparation
given to it, and the length of time it is kept beiore it is used, di«
tninish these deleterious effects, although perhaps they do not en*
tire I y remove them.
When a ridiculous Anglomania had possessed the IVench peo-
ple, they adopted the fashion of druiKing tea, and inimediabely all
the fine ladies had the vapouis ; the revolution altered t||e fashion,
and the vapours of the present beauties are now more trequently
•pretended than leal.
It would be more political to use the herbs of Europe*, some
,of which yield agreeable and wholesome beverages ; but if, how*
ever, fashion must have foreign plants, tht* Sjiauiards could fur-
nish the capraria biBora, and anserina oi Mexico, or the erythioxy-
lon of Peru ,* and the Ai^cricans, the ca&sii»e «f the Apalachian
mountains, the ceaoatlius,^ t4ie nionarda ot Osv/cgo, the psoralia
of the Jesuits ; or there might be pnjcured from New Holland,
the leptosperma, or the salsaparilla glyciphylla ; but it would be
^till better to cultivate at the lale ot France, the precious aya-
pana, which is superior to aU the ditferent i^inds of tea, in scent,
and every ather particular.
«■ iMf. I ■ ■ imn
t AM
Ohsercations, — The known aversion of Buonaparte to commerce,
and his earnest endeavour to provide substitutes for the articles
hitherto imported into France, were evidently the latent causes
that induced his obsequious apothecary to compose this paper, in
,Drder to induce the subjects of his master to forego the use of
t«a, as it is chiefly procured through the medium of the English
nation. However much we must, as merchants, deprecate this
^conduct, we cannot but do justice to the patriotism ot the author,
or rather of his imperial prompter, ijbere has already been
given in this work, some exceUent kiuds of British coffee, see vol.
iv. p. 440 and 470, and numerous papers have lately appeared
on the manufacture ofsugar, or a syrup, of equal sweetening trom
European plants. Alttiough a long c<<urbe of years will probably
elapse before these substances will drive the foreign articles al-
most entirely out of the shops, yet it is evident that the native
European products will at lust acquire the preemmence, in spite
of the great infiuence of the mercantile class.
Experiments on Sulphury and on its Decomposition, B}f Mr. Ct;-
RAUDAU.— -/tfii«. de Chim, vol. 67.
Although those bodies which do not suffer any alteratioa
from the agents to which they have been submitted, are usually
192 Mr. Curaudau on Sulphur and it$ Decomposition*
considered as simple, \et it is to be supposed that the principfe
into wi)ich the bodies of the njineral kingdom are res/ilved, ar
compound > ot the same retiiote pnncipies as enter ia^to the com
poeiuon ot'^ vfgftables and animals, and differ tVoni them only
by the very ^Tcat contraction which the principles must suffer
before they can enter into th« composition of minerals. The ap-
parent indestructibility of the proximate principles of minerals,
therffwre, aiibes from the diHiculty of making them undergo u
kind of ietrograd*tion, by their remote printijiles becoming less
condensed. In reality what other power, but that of the conden-
sation, and mutual atti'act.on of the principk's iif, minerals, cuulji
enable them to resist the dilating power of caloric. Fire, in
consequence of this resistance, can only be used as an interme-
diate a^'ent for their defitruction.
Sulphuric acid, strongly impregnated with nitrous gas, renders
water blue ; from whence it was conchi.ded, that sulpiurr conr
tained carbone. The solubility of sulphur in oils indicated that
sulphur might be a compound of carbone and hydrogen. These
conjectures led to an attempt to separate the supposed principles
of sulphur, or to combine them with a third principle that might
form with them a compound already known. For this pur-
pose, azote appeared very convenient, as it would form prussic
acid with the principles of sulphur, if they were rightly ascer-
tai.ied.'
Four parts of animal charcoal were therefore mixed with two
of sulphate of potash, and the mixture calcined in an iron tube.
The mixture was heated to a cherry red, and when* cooled, was
flung'into a sufiicient quantity of water. The liquor being fil-
tered was of a green colour verging to blue according to the posi
tion in which it was beheld. This solution had but a sligh
smell ot hydroguret ; and its taste, although not (^uite similar
to that of the prussic radical, lelt on the tongue a ta.ste which
'resembled it.
On endeavouring to separate the sulphur, it was found that
the acids, even the oxymuriatic, scarcely rendered the solution
turbid but they disengaged a particular and excessive fetid odour.
In order to discover whether any sulphur was really contained in
this. solution, a few drops of a solution of sulphate of iron oxid-
ized ad maximum was added to it. This throw down a blade
precipitate in abundance, which changed speedily to bliie on a
further addition of the sulphate. Wlience it was evident that
the sulphur had combined with the azole of the animal charcoul
and iornted a compound analogous to prussic radical.
Sulphuric aCid saturated with nitrous gas added ^ to tlie above
solution threw down an abundant yellow [)rccij)itate, which had
the appearance of sulphur, and exhalud the smell of it wh^'n
burned upon live charcoal. This prtcipitiitc was no other than
Mr. Descrmzilles on Violet pic/de, Sfc, 19$
t9i« radical, which might be changed, at the instant of its forma*
tion, into Prussian blue, by adding some sulphate of iron.
This radical, although analogous to the prussic, differed frona
it by a superior de(»ree of fixity, as it wds not disengHged from
its solution by the strongest acids, ahhongb they all of them
decompose prusyiate of potash ijumediately. The superior 6xity
of this new radical is probably owing to the condensation of
the hvdr<»gen contamed in the radical being as great as it is ia
sulphur itHelf ; although azote is able to lessen thi» condensation
by forming ammonia with hydrogen by the decomposition of
prussiate of iron.
The present experiments do not yield any data, as to the
determining wlu-ther hydrogen or carb^me be the predominant
ingredient in sdphur, or their relative proportion. But solutions
of sulphuretted azote of potash all contain an excess of car-
bone, which falls down, if the liquor is loft exposed to the air;
from whence it mav be concluded that the azote does not find
in sulphur the necessary quantity of carbone to convert :t into ^
prussic radical.
In another paper, the elements of phosphorus and iron will be
given, and the alkaline metals will be treated of, which somie
affirm nut to contain carbone.
Observal ions. '^The report made by a committee of the Insti-
tute appointed to examine this, paper will be found in this iinm-
her : and tbe observatiods there made absolve us from our task.
It is only necessary to state in general terras, that the analogies
upon which Mr. Cura^dau relies, in this or bis other papers on
different subjects, are very slight, and by no means sufficient for
the purposes for which he produces them, and that there is a
total want of that \iccurate statement of weights, &c. wiih-
put which th« best contrived experiments are of little use.
O.n violet Pickle y considered as a Test liquor ; and of' salting Vegc»
tablts to pnservq them for dial'Jlation, Ej/ Mr, Descuoizilles,
the elder. Ann. de Chun. vol. Gj.
Syjiup of violet is a very common ^test liquor for either acids
or alkalies, but it is subject to many inconveniences, for in warm
weather it terments, the corii Hies out, and the syrup either dries
up, or the iiifts get into it, are drowned, and alter its properties.
'lie nee, a brine impregnated with violets was found upon trial to
be preferable.
This brine, or violet pickle, was made by pouring upon the
petals of violets, sUghtly compressed in a pewter vessel, twice
iheir weighl of boiling water j the vessel being then, covered, wjfs
194 Mr. Rerthollet on Chencoi^'s Experimenis on Platma.
kept for some hours at a temperature rather superior to that of
baths, and afterwards strained through a linen bag, which was
squeezed very hard. The infusion being then weigiied, one third
of its weight of fine white kitchen salt was added to it ; by
which means a fine blue pickle was obtamed, that could be pre^
served in all weathers; even m the rays of the sun« and which
was far preferable as a test liquor to syrup ot violet. Lark-
spur flowers have also been tried, and succesbfully ; it is probable
that flags and several other blue flowers would yield a pickle
equally useful.
(Common salt may also be used to preserve vegetables. Rou-
elle p(^rfumed his elaboratory, during his winter course of clie-
mistry, in 1775, by distilling roses which he had salted in June.
Salted roses kept for three years have not ytjt lost their perfurue.
This pickling is performed by rubbing 51b. of roses at a time,
for 2 or 3 minutes with a lb. of salt, which, extracting the juic.e
of the flowers, produces a kind of paste that takes up but little
room. This paste must be kept in a close vessel, and a cool
place. When it is intended to be distilled, it is diluted with twice
its weight of pure water, this method of salting vegetables is
advantageous in bringing flowers, &c. from the places where
they are ^rown to the elaboratories in town, and in keeping those
vegetables ready for distillation, the distilled waters of which will
not keep for any time.
Ohsercations. — ^This is certainly a very gpod method of pre-
serving the blue juices of flowers, for the purpose of their being
used as re- agents ; nor is the method of pickling vegetables les$
useful.
On Chenevix's experimaits. on PUit'wa^ and on those of Dchccstils^
By Mr, C. L. Beutiiollet. Ann» de Chim, lol. 67.
Chenevix has shown, in the Philosophical Transactions, that
a combination of pUtina and quicksilver in certain proportions,
can sustain a violent heat without being decomposed, is fusible,
and has some resemblance to palladium ; but Rose and Gebleii
announced tha't they had obtained diff'erent results.
The method, pointed out by Chenevix, as the most proper, is
to boil quicksilver in nitric acid, and pour the nitr-ate thus ob.
tained into niuriatic solution of platina; a precipitate is obtained,
which on being washed, and reduced with borax in a crucible
lined with charcoal, yielded a metallic button, whose solution in
nitro muriatic acid was precipitated by green sulphate of iron.
This experiment was repeated, and a button was obtained, of
the specific gravity of 17. l)escostils having boiled a mixture of
Mr. Isdgrctngff on tht Lf fives cfnd Stalks df RUiharh, 193
grten sulphate of iron, and of solution of platina which contained
but a \^x'^ small excess of acid, obtained an abundant precipitate ;•
so that, this property belongs to platina itself: the precipitate,
however, when quicksilver is employed, is i'usible.
Descostils then tfe<ited platina with borax in a crucible lined
with lamp-black, and obtained a button exactly similar to the'
former. On dissolving this button, boracic acid was obtained.
Platina therefore combines with the whole, or some part of
borax, and the alloy has a metallic aspect, is hard, very brittle,
and crystallized in the internal pan. He has observed similar
phenomena with other metals.
The precipitate obtarined in Chenevix's experiment is not
fusible unless borax or charcoal is employed, so that its fusion
depends upon these additions, and not by the quicksilver. Che-
nevix himself had observed that platina might be melted by
means of borax ; this fusion was probably made in a lined
crDcible.
To distinguish the action of the two substances, Descostils*
treiited platina with charcoal only, and. obtained a button aug-
mented in weight 3 per cent,* whose specific gravity was 18. Thi*
carburet is very hard, very brittle, brilliant^ and kmellar in its
ifnternaT part.
Platina treated with borax only was not melted.
Observations. — If we recollect aright, Willis operated the fusion
6f platina by placing it upon a bed of coal in the bottom of a
crucibfe, but he attributed the fusion to the bed elevating the
metal to the hottest part of the crucible. His experiments arc
Contained in the English translation of CreH's Chemical Journal,
which was very eanrly discontinued ; but we have not the book at
Iiand.
On the existence of oxalic add in the Leaves and Stalks of Rhubarb.
By Mr. Bouillon Laguanoe. Annales deChimie, vol, 67.
SCHKELE knew of the existence of oxalate of lime in the root
of rhubarb; but the juice of the stalks and leav«s have not
been examined.
The yjittt of the leaves and stalks is limpid with a yellowish
cast, its odour approaches to that of melilot ; it is acid, and reddens
paper and tincture of litmus. The pare and carbonated alkalies
turn it deep brown, but do not cause a precipitation. Oxalate
of ammonia produces no change in it ; lime water forms a white
precipitate, whicn is unsoluble in water, but soluble in acids. Mu-
riate of hme forms an abundant white precipitate unsoluble in
water^ but soluble in nitric acid. Acetate of lead yields a
ig6 Mr. Laurens on the u^e of Soda ill th Soap-works dt Mhrseiilei;
yellowish white precipitate. The precipitatte from nitrate of
quickJiilver, or nitrate ot silver is white, and mostly soluble in
nitric acid. Muriate of tin y^eld^j a yellow precipitate.
From thfseexperim nts it appears that this plant .contains an
Hncombined acid analogous to the oxalic, and an extractive matter
which combines with oxides of tin and lead; but that it docs not
contain any calca.eous salt.
liy distillation, the juice yielded a lirtipid aromatic liquors
This liquor was not acid, it produced only a slight precipitate
with acetate of It^ad, which was soluble in nitric acid; it did not
allect lime water, barytes water, or muriate of tin. The re-
mainder of the juice being evaporated to a syrup, and left foi; 24
hours, yielded muph crystallised oxalate of potash. The mother
water was high coloured, and although very acid contained
scarcely any oxalic acid. The acid being probably the acetic^
combined with extractive matter, as in many other plants.
The mass being evapnrated to dryness, gave to alkohol at 40"*
hydr. a yellow tint; this tmcture was acid but did not /contain
oxalic acid. The undissolved residue was acidulous oxalate oi
potasli, which left on being incinerated nearly pure potash,-
slightly carbonated, with a small quantity of sulphate and muriate
of potash.
Ilence the juice of the stalks and leaves of rhfum palmatuin,
contains a great quantity of acidulous oxalate of potash, an'
unprystallisable acid, combined with an extractive colouring mat-
ter, which has the properties of the malic acid.
It is therefore no wonder that Scl:eele found oxalate of lime
in the root of rhubarb, as in many other plants, although in some
it was n^,essary,to treat them lirst with muriatic acid to dissolve^
the salt; and then- to precipitate it by ammonia.
On the use of Soda in the soap tvorks at Marseilles. Btf Mr.
Laurens. yJmiahs de Chimie, vol, 6j.
There exists a great variety ifi the nature of the soda usually
srold, and the quantities of alkali that it contains At present,
' the appearance of the soda aad its taste are the ot>ly guides to^
the purchaser, who is, however, well aware that it is only the
pure alkali that contributes to the saponification of the bil ; but
these criterions are not sufficient. Among the various proceasesi*
that might be employed to ascertain the quaiitity of pure alkali
contained in the mass, the following is pnd that may b^ practisec^
by any person. A given quantity of the soda is treated with'
Vr'ater until all the soluble part is dissolved ; to this solution, mu*
riatic acid (spirit, of salt) is^ to be added until it no* longer catts^-
an effervescence. The quantity of muriatic acid that must be
f
/
Jffr. LauratSf on th use of Soda in the Soap-uvrhs at Marseilles. 1^7
used to saturate diOerent specimens of soda, shows their relative
quantity x)f alkali : and the real quantity may be known by sa-
turating a known quantity of pure soda with the same mnriatic*
acid. It will, however, be fuund that the pi:ce ot 5oda is not
always regulated by the quantity ot" alkali it Lt)Uidins.
The sulphuretted j-oda exhibited by analysis, enhances the
price, and experience shows that it^oes not enter into the com-
position of soap. The separsktion of -this bulphu raited soda, as
proposed by Figuier, (see Retrospect, vol. v. p. 293) will by no
means iHtswer in an econotnical view.
Although sulphuretted soda does not enter in the composition
of soap, it produces a chemical phenomenon which is ol gr«fat
importance in the manufacture of that article, namely, the hydro-
sulphuretted oxide ot imn which occasions, the pale b'tie colour
that characterises the best soap. This colmir may be produced
bv mixing together ^leen sulphate of iron, ^nd a bydroguretted
ftlkaline sulphurett, formed either from potash or soda. This
phenomenon is daily observed m the manufactory at Marseilles;
Jtnd has been produced by addtng hy^roguretted sulphKiret to soap,
that had as ursual been treated with sulphate of iron*- Some ma-
nufacturers ascribe a power of destroying this blue colour to certain
Specimens of soda, hut lliis in fact is meiely owing tosulphurett not
being Ci>ntained in these specimens, so that ihey will not .produce
the desired, pale blue colour* ^
The different phenomena arising from this celour has a coti-
siderable influence on. the sale of tlie soap, and merits attention.
If one part of allialine Lydrogu retted sulphuret and four of
green sulphate of iron be added to the mass of soap, the
hydrOsulphuretted oxide of iron loses the blue colour and
acquires a rust colour. This effect, takes place when the soda
ased in making soap contains little or no sulphiiret. Two parts of
sulphate of iron, and one of alkaline hydrognretted sulphuret
produces a blue colour in the soap, which is altered by the air, so
that the soap acquires what is called an Isabella coloured mantle.
Equal parts of hydrognretted sulphuret and of sulphate, cause the
soap to be less altered by the air. And lastly, two parts of hy-
droguretted sulphuret and one of sulphate cause the soap^ to be
still less alterable by the air, and to acquire at last a blueish colour.
Now as the proportion of sulphuret contained in soda varies ex-
tremely, the manufacturers are obliged to leel their way by trials;
but they arfe well aware that an excess of sulphate of iron produces
that Isabella man lie which they wish to avoid.
It therefoie appears possible to determine by experiment the
good or bad qualities of soda in respect to the manufacture of
uiarbled soap, but this cannot be done without exactly d^tpreciat-
ing the quantity of sulphate and hydroguretted sulphunt that it
contains. It is also evidently necessary to abolish the use of
those drugs, which, although they contain little or. no alkali are
No. 24. — Vol. yu ' 2 d
}{!% Vauquelin and Bertholki <m CurwdauU experiments on Su^i^ir^^
nevertljeless used to produce the blue colour ; and as this colour
.(Can be p.oduced with scarcely any expence, the quantity of
alkim and salts coniained in soda ought to be the only stjandari)
01 its price.
The editon^ of the Annalts de Chimie take notice that Vaii-
quflin had already propo&ed a similar method to determine tb^
quantity of alkah in potash, and mentioned that it would als(^
serve for soda.
It is certain, they say, that the hydrogurctted sulphuret j^rodure^
p, very sensible effect on the colour ot marbled soap, l'>r it unites
with iron and oil, and tornis a greenish blue substance, which
dDc& not dlbi^olve in the soap, but ib merely disserninated through
it. 11 soipe fnsh made maibled soap is treated with warm
alkoboi, the undissolved residuum is this combination of oxide of
iron, ^uiphuretted hydrogen ^nd oil. When ochre is» used to make
^ed soap, a conibinatmn ot oxide ot iton, and even aUnniiie is ^
formed, which does not unite with the soap; but the sulphurettej
hydrogen does not combine with the iron, because it is not in a
proper state.
^■BBBi
Obseivations on Curuudau's experiments on Svlphur^ and its Decom"
poitian, Ry. Messrs, Vavquelin aiid Bcrtiiollet. Amu de
Chnnitt voL (57*
' ■
Thrse experiments of Curaudau would not have been noticed
if he had not himself loudly pioclaiaied xbeir importance as
inferior only to the der^?"P^^'^'^*^ <^^ water.
Curaudau's experiment (described in p. 192 of this number,) was
repeated with only this variation, that m^tead of iising an iron
tube some iron filings were mixed with the animal charcoal, and
sulphate of potash, with an intention to investigate the state of
the iron after the operation*
'A liquid like that desrrlbed by Curaudau was obtained by
elixiviatipi! tjie masb ; the lesidiiuru bein^ well washed was sul-
phuret of iron, from wrhence muriatic acid disengaged much sul-
phurated Lydro,gen.
' The liquid contains potash combined with sulphuretted hydro-
gen, and \\ith pru&fic acid, hot)] which may he disengaged from
it m a gaseous state by ndding sulphuric or Hiuriutic acid. It. is
&ht cuhnired by >( xne suiphuret of jn»n which is slowly deposited.
If a lAile boiution ci' sulphate of uon ad iimximum is pt-ured
into this Kquor, there i^*^ lormed a bldck precipitate ol sulphurnted
iron, produceu by il e sulphiiretied hydioj^en, because the super-
abunnant potash hinders ihe formation ot puitaiate of iron. But
Vvhen a large quantity of sulphate is addt^d, tlie sulphuret of iron
f decomposed by a part of the exccsb ol aCid ; the other pa^^f
Vauquelin and BertholUl on Curaudau\ eTperimenti <m Sulphur* 199
saCurates the potash. Prussian blue is formed and the liquor ia
(Changed from black tb blue.
Sulphuret of potash was treated with iron without charcoal;
and it yielded on elixiviation; a liquid which resenibled the former
in colour, although it did not contain any charcoal, and contained
hydrosulphiir^tt of potash, but without any prussic acid.
The pretended recompbsition of ^ulphur by adding sulphuric
licid impregndt(>d with nitrous gas to the liquid, is iiothing but at
j»rec]pitatiuti of th^ sulphur cdntamed In the sulphuretted hydrogea;
IVlalfaerbe many years ago proposed the decomposition of sul-
|)hate 61 soda, by charcoal and iron.
As to Curaudau's opinion res)}ec.tihg the cbtidens&tioii of prin-
ciples that takes place in minerals which he states to have beeii
adopted by Berthollet; it is difficult to conceive stny resemblapce.
between their respective idhas. AnU as to the decomposition of
potash into lime and azote, Curaudau was desired to repeat hici
experimients before commissaries named for that piirpose, but he
was hot able to exhibit the ledst signs of thi$ decompositiiin, and
it was supposed that he was himself convinced of it. But he has
lately communicated three experiments by which he pretends ta
confirm his former opinions;
The !irst he mentions, i's, that when instisad of elixiviatirig the
residuum of the calciufed mixture of animal charcoal, and sulphate
of pottsh; it is mixed with one fifth of very dry sulphur, avoiding
the contact bf air, and heated ; it yields at first much ammonia-
cal gas, and then carburetted hydrogen gas. The ley made of
the. cooled residuum, and ten times its weight in water, is darker
^han in the former experiments^ because it contains iriore carbone.
it also coiitains very little prussic radical, but oh remaining ex-
posed to the aii* for some months, it acquires by degrees a greater
power of forming Prussian blue, so that the principles of sulphur
Appears to combine with this azote of the atmosphere^ and formd
prussic radical.
On repeating this experiment, lill the gas was passed through
a bottle filled with water, which it impregnated with hydrogu-
tetted sulphuret of ammonia; the gas itself was chiefly sulphu-^
tetted hydrogen, and carbonic acid gas with some carburetted
hydrogen, and probably a little azote. Some of tlffe sulphur wa4
sublimed, and the residuum being elixiviated did not yield any
prussic acid, but hydrosulphuret of potash retaining a very little
sulphuret of iron. It is strange that Cuiaudau should conceive
that sulphur is decomposed in this experiment.
The second experiment ttrbuld show that sulphuric acid im-
pregnated with ilitrous gas destroy a prussic acid ; this may be,
but it is foreign to the question.
hi the third experiment, nitrous gas combined with sulphuric
iBUrid or nitric acid, precipitates sulphur from a liquor upon wiiidi
SCO Mesirs, Cuvier and Brongniari on tie
the other acids, not excepting even oxyznuriatic acid, had noi Wtn^
fiible action. But this is incorrect, for the acids disengaged sul-
phuretted hydrogen, from what Curaudau improperly calls
azotized sulphuret of potash, and the nitrous gas nnly decompuseji
the sulphuretted .hydrogen, and precipitates the sulphur. Sul-*
phurous acid produces a similar effect. Oxymuriatic acid does
not indeed sepaiate sulphur,, because it is converted into bulphuric
acid.
Ohserrat^'ons^^-^These remarks ol Vauqjuelin and Berthollet, are
fully sufhoent to shew how little foundation Curaudau had for,
his asseruov^s respecting the decompobixion atid analysis of
sulphur.
On the Mineralogic Geography of the imghbonrhood of Paris. By
- Messrs, CvviiR, and Alexander BauNGNiAitT. Journ. des
Mines, No, 13 a.
The country in which the capitil of France is situated is per*
' Baps the mo*t remarkable o\ an\ bitheito examined; on account
of the succession of the dili'erent fornuitions, the remarkable organic
remains "ih .t ihey contain, the ttlternate strata of «^pa shells, and
those of fresh water, the uuknownland animals, some of immense
size, which lie in the upper beds, and the very striking traces oC
a violent ernption from^ the south east which aie exhibited by
the shape ot the hills and the direction of the valleys.
The materials which compose the basin of Paris, have beea
deposited in a large open space, the sides of which are chalk;,
this earth being the most antient of all the formations here de-
posited. The formations may be thus enumerated.
1. Cha^ formation, in beds alternaiing with those of flints^
which appear to have be^n formed by successive and nearly pe-
riodical deposits.' The distance between the beds of flints varies^
^ being sometimes two metres, (yards) and at others even still
further. The chalk coivtains 1 1 per cent of magnesia, and 19!
of silica, great part of which may be separated by washing in the
form of sand. It does not contain so many petrifactions as the:
superincumbent beds of (oarse limestone. The petrifications are
also entirely different; in paiticular it does not contain any plain
regular spiral univalves. The upper part of the formation is
as it were broken, and forms a kind of fragment-stone of chalk,,
with clay in the interstices. The highest part of this formation
is 15 metrfs above the Seiner so thai the superiricumbent beds
are heightened, but they appear to be rendered thinner than usual..
In one place this chalk i? nearly naked in some points, being
only covered with a macly sand, which is almost pure at top^but
1 . -
Mineralogk Geograpliy of the neighbmrJiood of Paris. 2C1
contains in the inferior part o^ tbo Leil tragraents of fine grainecl
limestone disseminated in it. 1 ho?e fragments contain yellowish .
white calcareous geodes, with spathose lamina and small ca-
vities lined with calcareous spar. These p.eodes also icontaia
numerous spiral univalve shells, which seems to show that they
do not belong to the chalk formation. One of the geodes con-
tained a large cavity lined with limpid crystuls of sulphatcd '
stontian, or celestine, more than 002 metres long.
*2. Potters clay formation consi ts of a bed of unctuous tenacious
day containing silica, but very little lime; it does not etfcrvcsce
with acids, and is unfusiblie in a porcelain furnace, unless it con-
tains too much iron. It varies in colour, being either very white,
gray, yellow, pure slate colour, slate mixed with red, and pure
Ted, It is used for porcelain, and pottery, but it. sometimes con-
tains pyrites, small fragments of chalk, and cjrystals of selenite,
which render it less useful. The bed varies in thickness ffoiu -
01 or 0*2 metres (3 or 6 inches,), to l6 metres (yard&) or more.
It does not .contain any organic remains, for the frag Dents oi
bituminous wood discovered by Dolomieu, were fbund in a part
which had suft'ered some disorder, so that they were probably en-
veloped in. the clay posterior to its deposition. The line of separy
ration between the chalk and clay, is perfectly dis.ti act, and they
do not pass into one another.
3. Formation of coarse limestone. The coarse limestone does
not always lay immediately upon the clay^ but is sometimes sepa-
rated by a bed of sand. This sand does not conUiio any shells
*8o far as is hitherto known, but as the lawermost bed of limestone
is commonly sandy, and always full of shells, it is doubtful whethcK
the sand belongs to tke 2nd or 3rd formation ; the sand, how-
ever, procured from the clay, is generally sufficiently pure, and
refractory although red, or blueish gray, and frequently in very
large grains. The limestone is divided into several beds which
pass insensibly into each other ; sometimes several of these beds
are wanting, or very thin, but their relative order is never changed.
The very sandy limestone that constitutes the lowest bed is
sometimes friable; even when solid it falls to powder on exposure
to the weather. . It contains a green earth analogous to the terre
-eerte of Verona, ^.nd an immense variety of shells, of which
upwards of 600 spec leis have been already described, and which
Lave much less resemblance to the shells now in being, than
those found ia the superincumbent formatioas. They are for
the most part ia a very perfect state, well preserved, easily
ijetached, and many have not even lost their pearly lustre. The.
superior beds of this fjr)rraatiQn arc not so distinct ; they appear
to be first a^ soft stratum with a greenish tint; the lower part
2} as frequently brown impressions of leaves, ^nd stalks of plants,.
tbeo gray or yellowish beds cQntaining shells, the upper pari o£
~.\ '
iOf Messrs. CwoUr and Brongniart on, ike
ivbicfa is used for building ; lastly a thin bed of hard limestone
containing an immense quantity of tellinae squeezed together;
Above these come a system of beds of hard calcareous marie, the
fragments of which are iisUally covered with a yfeUow varnish
and black dendrites. These beds ai-e separated by beds of soft
iralcareous miirle, clayey marie, and partly by calcareous 'sand
Sometimes agglutinated together and cuntainihg bornstone with
horizontal zones, lo this systfm may also be referred a bed id
Ivhich crystals of quartz, and inverse - rhomboidal crystals 6f
calcareous spar ar^ found. No shells whatCfver arc fritxnd in thi^
npper part of the coarse limeiltone formation. It is evident that
the shells in this formation were deposited slowly in a tranquil
Sea, and that it was either gradually despoiled of its shells, or
had lost the property of preserving them.
4. Gypsum formation, consistmg of alternate beds of gy^sunr
and marie either Calcareous or claye)'^ The hills that contaitf
h ftffm a long bafiid running S.E. and N.W. and about IS miles
broad. These hills have a peculiar aspect, and appear like a^
Mcdnd hill placed upon the hills of limestone. The centre of this
band has three masses of gypsum.; the ends and outside have
only otte, which appears to be the uppermost of the three. -
Th^ lowest System of gypsum beds consists of thin alternate^
strata of gypsum, which is frequently crystallised, solid calcareous
marie, and very siaty clay marie ; the first contains the large
crystals of yeUowishr lenticular gypsdm, and the last contains the
toenilttc; iHo organic remains^ are found in this system.
The second system only differs in respect to the beds of
gypsum being ndiich thicker, and the beds, of mark less frequent*
One of tkese beds is of compact marbled grey clayey marie. It
contains fossil fish, and in the lower part some $ulpha;ted strong
tian in scattered kidneys.
The iippetmost system is much thicker^ sometimel^ 25 metres,- -
it contains only a few beds of marie, and iti some places lie^
alm6st immediately under thfe vegetable mouki ; th^ k)wer bed^
of ;this gypsuiB contains fHnts which pass gradually into gypsiimv
Ihe intermediate beds split into many sided large prisms, the
epper beds are thin, peneti^ated with marie, and alteri^ate with:
it; they are usually five in number. Thi^ svtftim cohtaihsr
skeletons of birds, and unknown quadrupeds ; when found in the
gypsum, they are solid, and covered with a thin coat of caN
careous marie, but when found in the marie they are very fri-
able. It also ccMitains, although but very rarely, fresh water
shells i if indeed Ol^ly a single one had been found it would suffice
to show that this formation had been formed in a fresh water lake«r
Above thi« gypsum are large beds of marie either calcaieous
or clayey; in the lower part of this system i^ a bed' of white*
friable calcareous marie which contains $iiic6)us trUiikd df ^il)bi*
Minerahgic Ge^grapky of tke neigkhmirkood af Paris. W^
I
trees. In one place are found shells of the genera, lymnea an4
planorbis, similar to those now living in marie ponds. Abave
|his bed are numerous, and frequently thick beds of marie, in'
nvfaiciir no petrifications occur. Afterwards there appears a bed
P'6 metres, (i feet) thick, of .a yellowish slaty marie, containuig
in its lower part nodules of earthy sulphated strontian, and a
little above it, a thin bed of small xellinae laying close one against
%he other. I'his very remarkable bed, which can only be disco^
:^ered l^y knowing its exact place in the system, has been found
to extend, upward^ nf 30 mileti in length, by 12 in hreadth. It if
the limit between the fresh water and marine shells, all above it
being of the latter kind, as well as the tellinae it contams. Im<*
mediately above this becj of tellinae is a very thick bed of green*
ish clayey marie, used for common pottery, which contains no
organic remains, but only argillo-calcareous geodes, and nodules
pf sulphated strontian : it serves ^s a guide to discover tbp bed
of tellinae just mentioned. The next four or five beds of marie
are thin, and do not contain organic remams, bat they are co-
veted with a bed of yellow clayey marie, containing fragments oi
marine shells, and of the palates of a kind of raia analogous to
raia aquila. The $i|ceeeding bed<» of marie contain marine
bivalves, and those immediately under the clayey sand contain
jtwo very distinct becjs of oysters, separated by a bed of whitish
marie without shells. The oysters of th«^ lower bed are large an4
very* thick ; those of the upper bed are divided into several
strata, they are brown, n|uch snialler ^ud thinner than the for*
mer : these beds of oysters extend throughout the ^hole of this
formation, Slaving scarcely ever been missed. The forin^tion
concludes at its upper part \yit^ a befl of clayey sand, which does
Ziot contain any shells.
It might be supposed, that this formation ought to be divided
into two ; one containing fresh water shells, and the other ma« ,
line shells : but the beds resemble each other so much, and are
jSo constantly associated, that it is merely sufficient to mention
the' division. Sometimes the upper marles are wanting, and
30 lAe times the gypsum is either totally wanting, or reduced tq
jt very thin beA In the former cases the formation is repre*
^nted by the green marie accompanied with strontian. . ^
5. Formation of sand and marine sandstone. This is but of
small extent, and appears to be a supplement to the gypseous
marles, but it does not constantly accompany them, and is fre-
quently separated by the considerable mass of clayey sand just
mentioned. It consists of beds of siliceous sand, for the most,
part pure, and often conglutinated into sandstone, filled with va*
rious marine shells.
Here it cannot but be obsetred, on considering the above five
formations, that at first' there was a sea depositing chalk, ^nd
S04 Messrs, Cteoier and irongniari on the *
different kinds of mollusca; this deposition ceased on a sudden, and
one of sand and clay, without any organic remains^ took place.
Another tea succeeded, which deposited a prodigious quantity of
shells of a different kind; by degrees these grew scarcer, the
place was covered with freah water, and alternate layers of gyp-
sum and marie were formed, which envelope the remains of fresh-
water-lake animals, and of those that lived upon its banks. The
6(a then came a third time, and left a few bivalve and turbinate
shells, but to these succeeded nothing but ousters. Lastly, the
productioHb'of the second &ea returned.
6. Formation of siliceous limestone. This is placed on the
side of the last, and supplies its pltice in the country to the E.
and b. E. of Paris. It is composed of distinct lavrrs of lime*
st^ne, sometimes soft and- white, at others gray, lumpact, very
fine grained, and penetrated with silica, which has iiaed its ca«
vities with mamillary stalactites of dii!'crent colours, and very
short crystals of quartz, usually vvitht>ut the prism, but trans-
parent. Tiijb limestone yields by calcination very good lime ; it
does not contain uny organic remains whatever. The stones
called nieulieres, millstones, are the siliceous skeleton of this
limestone, and may be imitated by' corroding away the calca-
reous part by nitric acid : so that this substance has been ex-
tracted by some uuktiown cause*, and bard porous masses, with-
out any appearance of stratification, are left, whose cavities are
still filled with clayey marie. This formation is frequently naked
upon the surface of the ground, but is sometimes covered with x
clayey marie, shell-less sandstone, or fresh water deposit
7. Formation of sandstone without shells, is always the up-
permost, or uppermost but dne, as it is never covered by any but
the fi'esh water formation. 'J'he beds are very thick, and mixed
vfilh beds of sand, which have sometimes been carried away by
water, so that the superincumbent beds are broken and displaced.
It does not contain any organic remains ; the sand is generally
very pure, but is sometimes mixed with clay, or coloured with
oxide of iron, or carbonate of lime has penetrated it in the
parts where it is covered with the fresh water deposit.
8. Formation of fresh water deposit. This always covers the
others, the rock, of which it consists has the appearance of the
siliceous limestone, and like that, forms millstones when the sili-
ceous part only is left. . It contains shells similar to those found
in our present mi|.rshes, viz. 3 species of lymnea, and planorbes,
besides those small round and channelled bodies called gyro-
gonites by Lamarck. The limestone, however hard, is broke
up by water, and is used as manure. To this formation may
probably be referred the sand found upon the tills, which con-
tains silicified plants, as this sand also contains flints filled with
the same kind of shells. This formation is usually found toward?
' Minhrdlogical Gtogmpky bj the niighbomiodi of Tarisl ^^
£e tops oft. hills and on large plains^ but .seldom .or never in val«:
ys. It shows that the fresh water formerly existing had the;
property of depositing beds of hard yellowish limestone, white
xnarlei anB silica, frequently very pure, whicK even changed thS
Wganir. bodies living in that water to their own nature ; proper^
tifes not pnssesseci by the present fresh Watei*«. -
9* Formation of mud. 1 his is composed of sand of all co«
loQrs, marie, or clay, or a mixture of all three, impregnated with
carbone, which > gives it a brown or black colour, it contains
rolled pebbles, large trunks of trees, the skeletons of elephants,
beeves, antelopes, and other large mamtniierous animals. It is
hot qnly.lound iii the bottom of the present vaUies,' but also in
places which have since been filled up* It is to these remains of or-
ganic bodies not entirely decadiposed that the dan^eroiis eiBuviauf
the formation when ^rst turned up are to be aittributed. Although
more modern than the others, its deposition was anterior to any
historical time^ and it may be said, that the old world was very
different from th^ present, since the woods and animals found
in this -forthatiiui aie entirely difl'erenU not op'y from the ani-
mals that now inhabit the same place, but even from ail those
known at present.
t • »
. Observations, '*^h\^ pap«T is more important than the gene i a-:
lity of those tbjit treat of local subjects, because the chalk basin
In ^hich Patfis is feitnated, also contains the rival capital, Lon-
don; the basin appearing to reach from some distance to the
S; E. of Paris to a line drawn from Dorchester, in Dorsetshire,
to the coast of Norfolk ; arid thus including the whole S. £. of
ftur island; and also from the great rarity of the chalk formation-
of which only another, situated at the southern extremity of
SSwedeh, and passing. under the Sea to Zealand acid the island of
Rugen, is known at present.
. Scarcely any sections of. the country in the neighbourhood of
London hav^ beeh published, on account of its not containing;
ores or i^oals, the great objects of miners ; but th« subject is
Wrthy of aiiention, and might, receive some illustiatioh by com-
t)aring the fe\y sections that are no# visible in diflerent places,
and the tCccodiits of the -^trat^ through which welts have beeii
8Uiik. ,
The alt^rnattoh of fresh arid *alt waiter shells is a[ remnrkable
fact, as such mutations of lakes have not been observed in mo-'
ilern times J but there still remains at least one instance of the
ftilicifyitig lakes in Lough Neagh in Ireland, which seems to be
gradually losing its petrifying quality. ' *
f revost and Desmai-est, junior, have since published a paper
in ^faich they mention the discovery of marine shells and otbef
'remains of sea* anijnals ifi the lnw^st system of gyp^^um beds ; d<j
bJo. 24.— Vot. vj. 2 t
2D6 Mr. Johns' JpparMifat iJ^ DeeomposkAn o/Pdiast M Sddd
thnt it » only tbe uppermost system that liM been d*poiited
from a fresh water hike.
OB
Improved Method 6f prtpdrin^^ Phosphorus Bottlts, — Phil. JotirH.
No. 117.
The phoshonis should be' carefully dried by filtering paper,
and a tbia ulicc being cot, it shuuld be divided into as many
pieces as Ibe time will allow, and the piseces introduced into c
small bottle, with as much lime as will surround it. The fooU
tia may, when full, and forked, be expoied before a fire hqUI
some<of the phosphorus has acquired an orange tint ; but if not
required for immediate use, this heating is not necessary,^ and the
omission of it will camte the phosphorus to eontinu* longer in a
serviceable state.
lime slaked in the air, and then ignited for ^0 hiinutes in #
Mack lead crucible^ is very proper for the purpose.
The mouth of the bottle should be closed with the finger at
soon as tht matth is withdrawUi*
ImsiBasaBaBsBimasmamsassiaammimiB^^
Description of an improved Apparatus for the Decomposition of tol'^
ash and Soda, By Mr, WiLLiAJi j6HNS.-rJ*/iJ/. Mag, No^
145.
Ma. Davy enjoying ample resources from the Royil Iilstitu-'
tiott, has given a method of decomposing potash and scKla by a^
bent gunbarrel, which is usually cut to pieces in order to get dui
the product ^ but this is attended with considerable ej^penses^^ and
therefore it was desirable to invent an apparatus in which this'
charge might be avoided.
The apparatus consists of a beat guhbarrel ;• an open potash'
tube is ground into the breech end, so as to fit air tight $ tb*'
bend at the small end of the barrel cdramences exactly at the
point where it quits the fireplace, and it is cut off aboOt three'
inches from this bend, and the piece cut ofi* again ground into tbi
place so as also to fit airtight. A small thin iron tube, open at both
ends, and made rather conical, is placed in the barrel when used,'
so thi%t the middle of the tube may come opposite to the la^ men-
tioned joint; this tube serves to collect the new formed metal*
loid. To the muzzle of the barrel is screw^ a stop eock, to the
other end q£ which is lated a glass tube, tht' l^wer end of which
is immersed in a cop of olive oil.
The iron turnings being brought tH a white heat^- the potash i^
supplied by degrees, when the last portion is added, and becinnt
red hot; then, and not till then, the stopper is jpii'ux the tttbe>tfa^
Mrp W^kefs new Scale for the Thermometer. t07
Jlttted over. The furnace uaed is a common black lead crucible
jibout 8 inches diameter, and the fire is blovrn by a pair of daubU
jbellows aboy t 36 in. by I f .
This apparatus served twelve times, and wa5 at last melted in
poe placjc, by the lute having fallen off. |n the last, 140 grains
i>f metalloid were obtained from 11 drachms of alkali. Common
caustic potash may be used instead of pure potash, which is eight
times as dear. In another expieriment, 12 drachms of alkali
yielded 170 gr. of metalloid.
Caustic soda used alone did not succeed, but two drachms of
.soda with 6 of potajsjb. yielded 6'0 g^rainf of a beautiful compound
nearly ^uid, very brilliant^ and apparently of the same specific
jgravity as naphtha. From 10 drachms of a mixture of 1 part
soda, and 7 potash, 15Q grains oi metalloid were obtained, which
resembled quicksilver, and was equally fluid at a low tempera*
lure^ but ^onlei op very pui)e .naphtha.
^sfspacfs^sfggwmafmm'SSSssasaaBsssmmssaBBBmt^
Qn a new ^cqlefqr the Thermotneter. B^ Mr^ Richard Wal*
i^£|i.-ri''iJ^» -A/tf^. No. 146.
' TiiERK are four different thermometric s.cales in use at this
^inie.
* 'Reaumur, by De Luc, 9* 80**
Celsius, 0"* XOO^
De risie 15Q^ 0«
The centigrade scale no^ used in France, \^ no other tbaa
Ibat of Celsius, to which d.ecimal divisions have been added*
Tbe proper place for 0°^ would, considering the thermometer
as a measure of heat, be most properly placed at the point where
beat commencejs ; b|it it is probable that this point will neyer
l>e ascertaibec), and besides, the scale would be encuriibeted with
a multiplicity of figure^ at, the part which would be in most fre*
^uent use.
It has been ascertained by physiologists, that 6^^ Fahr. is that
poitft Bt which the human body in a state of health, i$ uncon-
scioas of either heat or cold, in any season of the year, and iu all
climates ;^ so that any temperature above that pomt, £ives> under
ordinary circumstances, a sensation of heat, and any temperature
'below it, a sensation of old. With respect to the divisions,
those of Fahrenheit seem to be tbe fittest, in which case, the
freezing point will be —30"', and the boiling point 150®. The only
possible objection to this scale is the frequent use that it would
occasion of the plus and minus characters.
SPS 3fr Walker's nru: ScaUfor the Thermometer.
For meteorological observations, this scale is peculiarly appro*
pri'ated, the zero being the mean lempcralure between the great-
est beat and the greatest cold in the hottest aud coldest climates',
^blUctiveljr, as well as in temperate cH mates. Thus in Alrica,
the heat uses to M\^ Fahr., or 112° proposed scale, and in some
parts of North America the cold u —50*' Fahr. or -^1 13^ pr. sc.
So also in England the heat rose to 1:26® Fahr. or 6*4° pr. sci
<>n the a'kernoon of July 13th l80d, and the cold to —2^ Fahr,'
or —64 pr. sc. on the morning uf Christmas day, 1796. The
iriean annual temperature of Quito in Peru, is 62** Fahr., and tlie
limits of the variation arc only 3 or 4** above or below it; ani
this is considered as the healthiest spot in the world. By a welf
known provision in the ammal economy, a f«w degrees 6elow ()2^
Fahr. is much more uncomfortable than the same difference
above it.
Although Fahrenheit's division is here preferred, the mode o(
decimal divisions seems to be gaining ground, and might be em.
t)loyed, iti Which case, t*he freezing point of water would be —20*^
and there would occasionally be a slight difference, but all the
three leading' points are constant ; the remainder are n<>t of mucli
consequence, and the detect is common in every scale ; thus quick-
silver was really found to freeze at —38^ and two thirds Fahr.
tut is marked at — 3C)*.
The original idea was to place 0^ at the utmost degree of na-
tural cold, and in order to ascertain this point, a table was formed
from Kirwan's table of the mean annual temperatuie of every la*
titude, in which the tempeiature of the b'igh latitudes are deduced
,by inferences drawn from the others, and if- the results of this ta-
ble are correct, the greatest natural cold is a,t 68^ Fahr,, or 100*
below the freezing point of water.' If this point was adopted for
the 0® of the scale, the use of the sign of minus would only be re-
quired for such intense degrees of artificial cold, a:^ were below
that point, which so far as has hitherto been produced, are only
23, namely, — 91** Fahr.; the freezing point of water would be
marked 100*^ and the boiling 280°. v : > . t •
0!>serva{ion$. "^If we only consider the thing abstractly^ eithw
of two pro;^ osed points of 0*^, are more proper than the ai bitrary
scale of Fahrenheit now in use. We give the preference to the
first, or that in which the scale commences at 62^ Fahr., and is
Continued either way, as more agreeable to common language,
which has two diHerent words to express the upper and lower de-
grees, and of colirse most agreeable to those dictates of common
sense which should inipej philosophers to fix aud dt^fine the pre-
cise limits of comtiion expressions, but by no means to depart
from them without unavoidable necessity ; and we conceive tlie
scale would be more generally understood, if the degrees of t&e
• • •
Jfr. ParmenHer an the Gonurve ofGr^pc. U0§
■ f per scale were denominated those of heat, and the other, thos^
t)f cold, so that water might he said to boil at 15Q^ heat, add to
freeze at 30** cold.
The second scale l^a^ no other advantage over the common,
than that th<s use of the sign minus would he less freqaent that^
at present, a^ is stated hy ^he author.
We are averse however to 9^y alteration in matters of mer^
convention, from the confusion that it creates ; and as four scales
are alre^y in use, which occasion labour enough to (persons whq
read the works of foreign authors we do not consider the benefit to
arise from the introduction of a new scale, to be by any means
equivalent to the trouble it will produce.
On Comerve of Grapes and its jlpplication to making of ll^ne* Bjr ,
Mr. FiiKMENTiER. — AnHuUB de Chimie, vol. 6?,
To preserve the conserve of grape, twice as much juice of
grapes is taken as the boiler will bold; the juice is slowly boiled
Hnd the boiler filled up as fast as the liquor evaporates : when all
the juice is got in, it .s scummed, and the evaporation, contmued
potil thf liquor is reduced to three quarters. Tht; iiie is ihen di^
minished, and the mass, in order to prevent its acquiring a burnt
•ta&te, is kept continually stirred with a large slice, ttii the operas
tion is finished. \{ this slice is hung to the ceiling over the
boilers, so as to reach to the bottom of it, the stirring will . be
much less fatiguijag.
The conserve is properly prepared when it acquires a middling
brown colour, and when a piece as big as a nut is dropped upon
a plate, it does not spread upon the pUite. It should indeed be of
the coriSistence of hon^y, and poured very hot into very clean ves-*
sels, which are not to be covered untihit is quite cold.
A very considerable \x^ of (his conserve would be to give the
requisite degree of strength to the juice of tho6i. gtapes which urc
too watery to form gopd keepiqg wine, either on account of the
backwardness of the season, or the mature ol the plant.
In preparing the conserve, the farmer must beware of employ-
ing too much Ibeat ; it mus^ be recoljected that sugar candy loses
its power of crystallization by being kept too 'long over the fire,
it is indeed by altering the form of the boilers, so as to evaporate
the superfluous water wi^h the least possible use of heat, that it
.has been found practicable of late, to obtain more sugar than b^-
t«)re, with less treacle.
It would be desirable if the superfluous water could be got rid
of without the use of fire. Montgolfier says that he has made
l^xperiments for twelve years on thickening the juices of ft uits.
If I is process was similar to the graduation of sahae briiies;| and
SlO Mr^ LagrangifB Ukfrvpiions <m Cvraudmts Papery if^*
jiiffer oiily in the use of a very simple ventilator, by means of
"whicli be eaosed SO eubie feet of air per second to pads throngh
fogots of vine twigs from bottom to top. This quantity dissolve4
from 1 to 4 grains of water, according to its dryness ; and hence
a man working the ventilator for 1^ hours, caused the evapora*
lion of nearly 500lb» of water ; and 4 strong horses in a larger
Ventilating apparatus, might be made to evaporate (OOOOlb. of
water in ^4 hours, so that nearly 30p0lb. of conserve of grap^
luight be prepared in that time. He also fopnd that each cubie
ibot of air lost one degree of temperature by dissolyitig a grain of
iraterl
O^^erva/ion;.— -This paper is one of the many lately pu|)li8hed|
in France, to bring forward the produce of Europe instead of the
transmarine products of the colonies.
The idea of giaduatiiig the syrup by means of artififtial venti-
lation, might perhaps be beneficially extended to many similar
evaporations, and is worthy of the attention of sal^ makers, salt^
petremen, and others, in situations where fuel is scarce and XslL
pour cheap.
Obserwitians on Curaudau's Paper on tie Influence wkieh thtfim\
' cj utilh txercuci on the products obtained. By Mr. Bouillov
laAOB.A^GZ.''r-^Jnnafesde Ckhnie^ vd* 67. •
CvHAUDAU says, that although the stills made on the princi-
ples proposed by Chaptal, pf a lar^e evaporating surface, are the
best for quick distillation ; yet the coutrary shape, or tall narrow
stills, vield liquors of much finer flavour.
The broad low stills proposed by Cbaptal, ^ere impiediately
adopted b^ the roanafactorers of brandy ; bat the difficulty of
transpbrttng that liquor by sea, in' consequence of the war, has
occasioned a preference to be given to spirit of wine, as the small
bulk of that liquid occasions a saving of fifty per cent. In the car-
riage, although the mixture of it with water, is by no means so
'agreeable as real brandy.
' For the last five or six years, stills superior to those of Chaptal
have been invented and employed in the south of France, These
stills mav be divided into two classes.
The first class comprises the apparatuses invented by Solimani,
* Fournier, and Isaac Berard, who adopted* the ideas of the ancient
chemists, of passing the vapour through large serpentine vessels,
immerged in water of a proper temperature, in order that thcv
aqueous part of the vapour might be condensed and separated
from tht spirituous, which is carried into another vessel for con-
'densation, and is of course founded upon the principle thatalko«
l^^i Henry on HorM^chesnwt. Sll
hoi iLtid water condensa at different temperatures. Gay-LussaC
heA fliiown however, that tH^ attraction between the vapotirs of
wat^f WKi those of alkohol^ hinder ihdr being completely sepa^'
tated.
The seroiid cla^s was originally proposed by Edward Adam, in
which the preceding principle of the aatients is not only adopted^
but also a new one. Ftir a series of stills is heated by the steiafli
of a single one> the 6rst oh the series, which is passed through
ihem successively in serpentine tubes. The condensing worm of
the first still heating the- second 'still, and so on, by which several
distillations are carried on at once, each yielding a product of
different strength.
All the apparatuses are accompanied with a great economy iff
ihe use of the fuel. In some, the vapours to be cocdensedt ar#
^ployed to heat the wine that is next to be distilled. In others^
ih^ heat that usually escapes, is used for that purposes Thi9dis«<
peeition obliges the distiller to work night and day, until his msu
ierials are exhausted*
lilt elasy to conceive that spirit of £my repaired strength n»y
De obtained, according to the dis lance that the vapour is obliged
to-pa^ss, before it arrives at the condensing apparatus*
It is therefore evident, that Chaptal made a great improventent
in the art of distillatipn ; and indeed it must be observed^ that
the distilling of wine is different from that practised by apotheca-
H^, in which the whole of the vapour that is raised, is required
•to be condensed*
■ I'lii II I I < »—
Obscroaikms.^^Vft shall hereafter have occasion to revert to"
ibis subjec^t in a future paper, where the form of these Compound
stills is described more at length.
On Horu-Chesnut. By Prof. Henry, of Parti, Ann. dt
Ckim,^ vol. 67.
ParmentIsr says, that a fecula jrouldfbe prepared from the
fruit of the horse-cheSnnt, (aeSculuS hippocastanum of Linnaeus,)
and thstt, if this fecula were carefully washed, to take away the
bitterness of the parenchyma, it might be used for food. Mar-
candier affirms, tbat a ky of the fruit is used in Switzerland to
Wash linen. The fruit has been long knoAn to contain potash,
which might be obtained from its a&hes. Beauuie published an
essay on this fruit, but the processes are too. complicated for do*
inestic use. Parmentier and BoUillou- Lagrange, have compared
the bark of this tree with quinquina. Zannic belli, an apothecary
at Vcflite, employed this bark in 17 23^ against intermittent fe-
vers.
f !• ^Tof, Henry on HorseAAtimdl
The bark of horse-cbesnut should be taken oiTbranches of th}^
br four years old ; it is blackish externally, and whitish internally,'
its taste is bitter, but not disagreeable. It is very difficult to piil<^
verise, and when fresh powdered, smells like cacao.
Cold water at 220' or 24"* Reaum. (77'' or 86^ Fahr.) poured
upon the bark) almost immediately exhibits a violet colour by re«
flexion, and takes in a few minutes a fawn colour ; the infusioit
lathers wdU it is bitter^ but not astiingent; it reddens infusion of
litmus*, and yields a dirty white precipitate with isinglass* Oxa^
lie, sulphuric, nitric^ oxymuriatic^ or acetic arid takes away its
colour, and throws down a little precipitate. Potash or ammonia
increase its colour, and the surface of the liquor appears deep
blue. Barytes throws down a precipitate of the colour of lees of
wine. Sulphate oi iron changes it greenish, and if more of the
sulphate be added, a greenish precipitate is thrown down. Emc^
tic tartar is not decomposed by it, oxalate of ammonia renders
it turbid, mnriate of barytes yields a fawn yellow precipitate; iu<^
trate of quicksilver ad minimum yields much precipitate^ which
leaves the liquid colourless. Neither decoction of tannin, nor the
infusion or decoction of quinquina atfect by infusion.
The decoction of horse-chesnut bark, has the same properties as
the infusion. If a few grains of subcarboiiate of potash are added
to the water^ the docoction has a very deep blue colodr by t^l
fleeted lighti
Alkohol at 34S'° Cartier digested on the bark for 48"^ hours
with a moderate heat, yield a tincture with a slight greenish tsnti.
Water did not render tbis tincture turbid, but changed it to blue.
Brandy at ^*2° acquired a much deeper colour.
. Wipe dissolves the extractive principle oi the bark, and be*
comes blue by reflected light.
The watery infusion being evaporated to a synip, and left for
25 days, did not afford any saline matter. During the evapora*
.tion it became of a deep red, but was still transparent. Towards
the end, and on cooling, it deposited a secfiment, which was soft
to the touch and efl'ervesced with acids; this substance appears to
contain much alumine and a carbt/nate.
Twenty grammes of this substance b6ihg dried and distilled^
yielded Watef, oil, carburetted hydrogen gas, sorne earbonate acid
gas, carbonate 6f ammonia, and ten gramnies of very friable char-
coal, which on calcination yield 2-7 gramme^ of ashee^ containing
a little free alkali, sulphate of potash, auli a Substance uiisoluble
in acids.
One hundred gr. of dry bark yield €5 of extract of the consis-
tence for pills. This extract is reddish brown, and when dissoF-
ved in water, the liquid i^ blue by reflected light. If the extract
ii dried Opon plates in a stove ur water bath, it forms hyacinifii'
colour scales, which attract the moisture pf the air.'
JW>. Trommsdoffon art^cial Succinic jfdd. tl$
,. trhe l)ark of horse-chesnut seems to have no analogy with that
tof quinquina in a chemical view*
Observations. '■^Here we have another of theanticoJonial papers^
IThe war which the British ministry carried on against the French
Vspitals, by endeavouring to hinder them from procuring Peru?
yiau bark, will have at least the good effect of bringing into prac-
tice some native vegetable substances, v^hicU will either be sub-
l$tituted for. that expensive drug, or may at least be usea as a sue-
cedaneum in a scarcity of it.
" 'vv'iT ,""■";"'..
Oh crrtificial Succinic Aiid, Itompailiuss tulphurett^'d Alkohol^ Fecuhy
and Cadet's aqueous JSUution of Camphor, Bj/ Mr . Tromms-
doiif. Aiinaies de Chimief voL 67.
. Succinic acid may be obtiitted by distilling saccholactic acid
without any addition.. . ,
: Lampadiu6*s sulphuretted alkohol does not contain any car-
tone, and ought to be called oily hydroguretted sulphuret. It dis-
solves very speedily eight tiines as much phosphorus. The. solu-
tion is still liquid, and easily takes lire by contact of air', on be*
iug distilled, oily hydroguretted sulphuret passes over, and then
the phosphorus; the sulphuret con lains some phosphorus, for the
blue iBame is succeeded by that of phosptiorus.
The. solution of fecuta in boiling water being thickened by ^
gentle firei yielded a seiiii transparent horny substance, not at all
soluble in hot water. '1 his substance heing moistened and leit
for five months in a wanii place, did not shew any signs of ier-
mentation. Hence ferula ought not to be emplv*>yed in pharmacy
for preparing masses of pills, but gum arabic or iugucatith should
.be used. - It also shews how miich vegetable matters are altered
even by water.
The solution of camphoV in distilled water is rendered turbid
by pure soda, and therefore cannot be used rts ^a test tor potash*
Vogel observes that this solution is also rendered tuibid by
^IphatH and nitrate of soda^ muriate of lime, aifd other salts'.
jBut soda containing some carbonic acid does not alter it, and in
general the precipitates obtained by alkalies or salts aie very so-
luble in water, and are taken up again when the solution is exl
il>osed to the air. Trituration alone wUl eiuible water to take up lb
grains of camphor pier quart.
' «
'On the Qmfposition ofAnmonia, By Mr. Bf.rthollet, Jimior.->
Antiales de Vlumiey vol. 67*
- Thk ohiect of these rcaeairched was to ascertain wlie.her am-
1
214 Mr. Tvtiici^B Uethod ofjiiting up an klettrk Cotttmn,^ e,
ni«nia really contained any oxygen, as Davy had asserted it coD'
taiued no less than ^0 per cent, oi that gas.
The expansion oi ammohiacal gas by repeated electric shocks,
'wliicb separate its elements, was ascertained with the utmosi
precaution, and 100 ifneasares 6t that gab. were ipuhd to heaug-
nienied to 294. The expai.ded gas contained 75'5 parts of hy-
drogen, and 24*5 oi azote. Whence it follows that one Hire
(quart) ot' aunnoniacal gat, yieldi^ 2 04 Hires of a mixed gas, cora-
pos'd of I 04 litres ot Lydrogeii, ano 0*5 litres of azote.
From the data of Biot. and Arrago in their paper on the
reiructin^ pnviei of gases, it may be deduced that at the freezing
point of water, and under the pressure oi 0'J(> (30 in ) the litre
oi hydiOgf u weigh' 0095 grammes, and thai ol azoVe 1 259 g't)
and iiincLi* nial gab t'i^b gr. ; so that tlie sum ot the weights of
tt.e hydrogen and azote contained in 6*775 grammeis, or a litre of
ariimoni'ical gas, is, according to the above stated proportions;
0'77^ g»ainmes ; which agrees as nearly as possible,* and gives
the pr< portion by weight as 18*67 oi hydrog^^ and 8ir'13 of
azote.
From this accurate expeifimeftt, it fallows, that ammonia fs
c(>fi;po&ed orly of h>drogen an«l azote, and does no^ contain an^
oxvgen, unless at least it can be extracted by some hitherto un-
discoveicd niethod from those gases which have always be^n looked
upon as pnie hydiogen and azote.
1 he mixed ^as collected by passing ammoAia through aH
ignited tubf oi porcelain, was found to c«>niain the same propor-
tion of hydrogen and a7ote. In one experiment, 20 litres (quarts/)
of auiiiioniai gas was decomposed, and evrry precaution taken to
condense the \\ater thai ought to be lormed if the ammor.iacal
gns liad contained, as Davy stated, one fifth of oxygen, but no
^dter was obtained. Neither was any humidity observed in
the dt coroposiuon of the gas by eieciricity, nor amy signs of
oxydizeiiient when an iron v. ire v\as used as the conductor, orA
Ol other i>t which etlectb ought certainly to have been produced
if the aniiiionial gas contained oxygen.
OUervafionsj — Mr. Davs has replied to the theory of the French
chemists, in bis last Hakt^rian lecture, just pBl?lished in the Phi-
losophical Tranbactioris lor 18-0.
Ddycriptioti of a Method of filing up in a portable Form the Electric
Co'umn lately invented by .yJf. J. A. Dl Lue. Also an Jccowit
of never al t:i:p:rtyie?ih made with it. By Mr. B. JVJ. FoitsT£«-
FhiL Mug. iSio. ]43.
In consequence ot the effects produced by Mr. Dc Luc's EI«c-
\
Mr. Forslet^M method of ^ttpig vpan ]E,kctnc Column, Sfc, 215
l^ric column (which consists of small circular plates of zinc and
melal paper, alternating in pairs, and connected together by a
^ilk string passing through them, Mr. Forster was led to make
soifae experiments op its constiuction and application.
Two hundred circular plates ot zinc ol about 5.^8ths of an inch
in (jliameter, and an equal number of discs of Dutch copper leaf
pasted on pieces of blotting paper doubled, were connected toge-
ther by meains of a silkjen string passing through them. This
small combmation acted sufficiently on a very delicate gold leaf
electrometer to induce Mr. Forster to increase it to 500, using
silver leaf instead of D^itch metal. The whole wjere enclosed in
a glass tube, with brass caps, screws, and balls. The series iii
this state, is termed by Mr. Forster, an Electric Rod. With
this instrument he pet formed a mimb^r of experiments, 6uch as
lexhi biting attractions and repuUions on a gold leaf electrometer,
Dutch leaf, and a ve^y light ivory needle, turning on a point like
a magnetic needle. And in one case, when the electric rod was
placed at the bottom of the electrometer, one end being held at
the same time in the hand, the gold leaf was attracted, which
shows that the instrument acts through the air.
It also slightly charged a coated jar. And what* is singular,
the inside ot the jar, when charged by the zinc bide, gave s gns
of minus electricity, and the outside of plus^ when excited amber
^as brought near it.
The ivory needle vibrated, whjen it was placed bjetween the op-
posite poles of two rods. ^
Three rods combined occasioned a diverging in the pith ball*
of Cavallo's electrometer, but produced no effect on the tongue,
as is the case when a single plat€ uf zinc and silver is brought in
contact with it.
When three rods \yere combined, and two bells connected witb
them, having a small brass ball between the bells, suspended by
silk, a ringing was produced, which continued for a consider^iblc
time. If a perfect insulator could be Ibund, the ball might pro-
bably be so adjusted as to occasion a perpetual vibration for
some years.
Observaiions. — ^The Electric Column of Mr. De Luc, though
ijpt novel in its principle, may be considered as an ingenious in.
strument for indicating the hygrometrical state of the atmos-
phere. It is only in consequence of a minute quantity of mois-
ture that it is rendered active for when the paper is thoroughly
dfied, no ele«^rical effect is produced.
These experiments of Mr, Forster do not seem to lead to any
ifaing novel or important.
•*i
( v^ >
mmm
Qn tie Acids produced by treating Givger Hoot with Nitrie Acid,
"^ Bj/^. Le Gay Bhewertov. — P/nL J/untal, No. 113. ' '
It was announced in the Phil. Jonrn. ^Jo 105, (Retrospect, vol*
y.) that a new aciil called the zingit)eric acid had been obtained;
from ginger .Mr. Bi^werton instituted some experiments to exa-
mine this acid and its comb. nations.'
- Jam£iica ginger was treated with diluteJ nitric acid, and kept
at a boiling heat during i2 hours; i$ was then saturated with
Carbonate of lead, and filtered, and the directions given for obi
taming' the ncW acid were followed £[& nearly as possible; a
Whitish salt was obtained in filiform or capillary crystals, which .
^ere not acid, but nsipid to the taste, ^lightly soluble in water,
Itnd giving, -with barytic Water and oxalic acid, a dense white
precipitate insoluble in vinegar. Ihestt properties seemed to
shew that this/ salt was sulphate of lime.
The experiments were varied and repeated with similar results;
and there were no iitdications whatever of the presence of aoy
tiew acid. ' . • ■
When ginger was digested with nitric acid in a more concen-
trated torni fur some tiriie, then mixed with water, boiled, filtered
and C(>olecl, prismatic crystals were obtained ; tiaey were intensely
acid, very soluble in water, and gave with lime water a dense -
white precipitate, insoluble in vinegar. A part of the fluid also»
do being artber evaporated,, assumed the appearance of syrupy
smelled like burnt sugar, was not very acid to the taste, and with
lime wHwcr, slowly deposited a white flocculent precipitate, sil-
iiM>st entirely soluble in vinegar : there were also a fevv' prismatic
crystals visible. These erysrals, Mr. B. conceives, are oxalic
acid, and the substauce of a syrupy consistence, principally ma-
lic acid. • . .:.!..-
uji'.j !l■J^yBfr^^,'*'^JUilii
New eiectro^chemical Researches, on rafious Objects, particularly on
the metallic Bodies from the Atkabes and Earths, and on soine new
Combinatums ./ tlydrogenl By Mr, iiujtfPHRT Davy. — FhiL'
Trans, Fart j] IHIO,
. Messrs. Gay-Luasac and Thenard suppose potassium and soda
to be compounds of p'Uash and S'»da with hydrogtl^ and main*
tain this opmion, by asserliHg that when potassium is heated in
amiiH nid the ammouiii is absorbed, and hydrogen produced : ott
heating the olive subsUiDce produced m this experiment, 2-5ths
6t the ammojHa is ditJeiigagetJ, and the elements, i. e. azote and
hyd]-»geii, o1 anottier fifth pMrt . by addmg a little water to the
Residuum, the remaining 2-5 ths of amaionia were obtained, and
J
Mr. Davy's nrju Elcctro^chcmical Researrha, HT
nothing but potash was left. And further, that by reprating thi» »
i)peration, the^ could produce from a given quantity ot ammonia^
ihore than il^ volume of hvdrogpn.
Ii> proportion, however, as more precautions are taken to pre-
vent moisture Irom being communicated to the olive substande,
80 much less ammonia is n-pMuuiced, and ihus as much as 1-1 0th
of the original quantity was seldom obtained; neither has the hy-
drogen and nitrogen been procured in the proportion to form
ammonia, biit the nitrogen has always been in excess, and a
considerable quantity ot potassium is always revived.
Bar. 30-2 inches ; therm. 34° Fahr. 3. grains and an half of
potassium heated in a platina tray in K cub. in. of ammonia in
U glass retort free from metallic oxides, absorbed 7*5 c. i. and
'evolved 312 c. i. o( hydrogen. The fusible substance was covered
"xvith dry quicksilver, and immediatelv introduced into a tube of
platirik bored from the solid, having a stopcock and adaptor of
brass, corimcted with the mercurial apparatus; the lube and
adaptor we^e then exhausted, and filled with hydrogen, of which
Ibey contained 0 8 cub. in. On heating the lube slowly to
Xvbitenpbs, 9 cubVin of gas were given off, and 0*5 c, i. remained
In the tubf. 0.2 ctib. in. of the gas given off was ammonia, 10
measures of the permanent gas mixed with 7*5 of oxygen, and
iacted upon by the electric spark, left a residuum of 7'5. The
potassium formed, produced, on adding water, 3*3 cub. in. of hy-
drogen. Whence there is but little difference between the analy-
sis of ammonia by electricity, or by potassium, but some hydrogen
app.ears to be lost.
Bar. as belore : therm. 5^^ Fahr. 3 gr. of potassium treated
in the same nidnnti, absorbed 6*78 rub. in of ammonia ; and
2 '48 of hydrogen were generated. The distillation was then per-
formed, the lube and adnptors being tilled with common air only;
3 cwU. in. of gas weie evolved, and no doubt the same quantity
remained in the lub- as ii. tl e former experiment. The evolved
gas scarcely contained 0*4 cub. in. of ammonia, and the unab-
sorbable part df^tonated with oxygen in the pi^oportion of 1 1 to 6,
left as before, 7*5. The regenerated pctabsium produced 2*9
cub. in. of hydioKen. Here, as before, there is a lobS of hy-
drogen.
' When the potassium left in the tube was made to act upon
Water, a black matter was separated in fine powr^er ; it hHd the
lustre of plumbago, conducted electricity, took fire at a tempera-
ture beiovv ignition, absorbed oxygen, and formed pure wat- r
Svitb it, leaving <>nly mmutply divided'piatina. Of this powoer
from 4 lo 6 grain- were ii'riiied when 3 or 4 grains of potp^eium
acted np»' r. .inimonia in a platina vessel, and wa.5 disiilbd in con-
tact .with LD-.il mrtiil.
' When an iro» tvhe is en:^)ioyed in tn-atMii! rotassium with
amtBoma^ liome azote is lo&t; a part of the potassium is changed
A.
19 Mr. Dav^i ffea> ElectrOmc/ttmicai Resedrches.
into potash, and some h)'dr<)gen is produced. In copper tubeii
more potassiutii is revived ; and the hydrogen bears a small pro-
portion to thf" azote. In plalina tubes, there is little or no ios^
of potassium or azote, but more or less hydrogen disappears.
5'3 grams of sodium absorbs 9*1 cub. in. of ammonia, an^
produced about 4*5 of hydrogen. When distilled, it did not give
off l-20th of the ammonia that disappeared, but 1^ cub. in. of
gas were obtained, which consisted or about ^ parts of hydrogen,
and 1 of nitrogen. Tlie action of sodium upon ammonia is less
violent than that of potassium, it does not effervesce, hut is silently
combined with one of the eleraeutb of ammonia, while the other
escapes in the form of hydrogen.
Curaudau a(firn^s that the metals of the alkalies are composed
of the alkalies united with charcoal, and that carbonic acid is
formed by th^ir combustion, but his metals contained charcoal
accidentally mixed with them.
Ritter's argument in favour of potassium and sodium being
compounds 01 hydiogeiie, is their ex ireiott lightness. — noofteis
more ecunfy answtnd. Sodium absorbs much more ox^geue than
potassium, and on the hypothesis of hydro^e nation must contain
much mortf h^drogene; yel though soda is s^id to be lighter than
potasb, in the proportion of 13 to 17 nearly, yet sodium is heavier
than potassium in the proportion of 9 to 7 at least.
Ritter has observed some curious circumstances relative to telr
lurium (see p. 1S4) which he conceives to prevent the.metalliza*
tion of potash, by having a stronger attraction for hydrogeue
than that alkali. But in reality they contirm the idea of potasr
sium bting as yet like other metals undeconi pounded. When tel-
lurium is positive in water, oxygeii in given off; when negative,
and the buttery contposrcj of more than 300 plates, a purple f)ui4
separates from it, which renders the water opa(}ue and turbid,
and a brown powder is deposited; the purple fluid is ^ solution of
telluretted hydrogen gas in water, which absorbs some oxygen
from the air in the water, eyolves a little hydrogen, and falls
djwn as solid hydruret of tellurium. When muriatic or 6|iiphuric
licid are present in the wuter, the ga? is not taken up.
Potash, in iis common state of dryness was act^(j upon, hj
1000 double plates, from negatively electrified tellurium. Ibe
action was violent, a metallic :iiass not unlike nickel in colour
wa£ f«rined, which did not inflame nor effervesce with water, but
changed it of a beautiful purple, and was totally soluble in that
liquid. The metallic mass was probably a couibiuation of tellu-
retted hydrogen with oxidized potassium. It effervesced violenti/
with dilute muiiatic acid, with a smell resembling that of suU
phuretted hydrogen, tellurium was formed where it was m contact
with the air, and muriate of potash remained in solution.
Tellurium and potassium heated in hydrogen gas, combined
toother with vivid light and heat, and fqrmed a dark coppef^
Mr, X)<iryV new Electro-chemical ResearcJies. 219
tioloiir alloy with a crystalline fracture, brittle, and not fusibU at
k red heat. When the tellurium was nearly equal in quantity to
the potassium, riu hydrogen was evolved by the action of water,
but the compound of tehurett^d hydrogea and potadh remained
tiibsolved in the water.
100 grains of oxide of tellurium, 20 of potash, and 12 of char-
coal distilled together, yielded much carbonic acid, and an allojr
bf tellyriHrn and potassium ; a vivid light appeared in the retort
even before it was red hot. In attempting to* reduce some oxid^
of tellurium which iiad probably been prepared with potash, th«
alkali that adhered to it produced an alloy which was of a gra^
colour, very brittle, and more fusible than pure tellurium.
Telluretted hydrogen gas has nearly the same smell as suU
phuretted hydrogen, and the analogy of these two substances
i^ds so great as to lead to a suspicion that tellurium contained
sulphur, especially as most of the metallic sulphurets which wer^
Conductors of electricity, also absorbed hydrogen when made the
negative Surfaces ; but this idea was after war^ds abandoned. Thfe
^olbtidli of thi$ gas in water is claret Colour, but it sooti turns
brown, and deposits tellurium by exposure to air. When newly
disengaged from an alkaline solution by muriatic acid, it reddens
fnoisiened litmus, atid after being washed with a little water, it
loses this property, but it is in this case partially decomposed b^
the air in the water; in other respects it resembles a weak acid/
Combines with the alkalies, and precipitates most metallic so-
lutions* It is instantly decomposed by oxymuriatic acid, do*,
positing a film of telluiium which is soon converted into muriate
t)f tellurium. It seemed as if tellurium would combine wUh dry
hydrogen by being strongly lieated in it.
Arsfenic having an affinity fur hydrogen, it was miade the nega-
tive surface in water, with 600 double plates, it became dark
Coloured, threw down a brown powder, but also evolved inflam-
tiiablcS gas. Wh^n negative in a solution of potash, some gas was
evolved, the solution became brown, and remained pellucid, but
an acid rendered it tuibid and precipitated a brown powder. Arse'-
hic negative in contact with solid potash produced a dark
gray perfectly metallic alloy of arsenic and potassium, which
took fire on adding water, yielding arseniuretted Hydrogen, and
depositing a brown powder. Potassium and arsenic heated in
hydrogen, were inflamed and yielded a similar alloy. It was at
first thought that the volatile phosphorus produced by Cadet, by
distilling acetite of potash with white oxide of arsenic was au
alloy of potassium and arsenic, but although the potash is dp-
composed, the volatile substance is nut an alloy of potassium but
contains charcoal and arsenic, probably with hydrogen; the very
fetid inflammable gas not absorbable by water which is given otf,
seems to contain charcoal, arsenic, and hydrogen.
£asily fusible alloy of tellurium with minute quantity of po-
C^O Mr^ Dcftvi new ■Ekctro^chemkal Researches* . .
tassmm aUbve mentioned, lieuled in amaiouia, yielded a dar^
brown subhUnce which gave anununia by exposure to air. The
residual gas contained 4-6ths ot nitrogen a^ote. The residuaj
gas left in ihe action ot auimonia upon an uHoy of arsenic, aud
potassium also consisted principally of nitrogen.
Potassium burned in oxygen gas, upon a piatina ti'ay, absorbs
J1.20ths of a cubic inch ol oxygen toi every griiin of mutai con-
sumed, and every grain Of sodium takes up in this manner about ^
a cubical inch. The alkalies thus lonned are in a slate of extreme
' dryness, are only imperiectly fusible at a red heat, and do not, like
the easily fusible alkalies, give any indications ot luoiscure.
D'Arcethas shewn that poiaahand soda in their common state
contain water, and BerthoUel concludes,ihat potash which has been
fused for some time loses 13*89 pt^i* cent, of water when ii corn-^
bines with muriatic acid, and tbat munace of potash contains
66 6 J per cent of potash, and 33 34 of aiuniiic acid. When po-
tassium was tiealed with liq*ud inuriatic acid, hydrogen hiilding
potassium was evolved, and yet 10 parts of poiaosium produced
17 '5 of dry muriate of ]>otd.'h 5 gr. of potassium abborbedabout
W cub. in. of dry muriatic acid ga^; 5 of hydrogen were evolved,
and the platina tray increaaed in weight about V'5 gr. and did
not lobe any of t-iis weight by beiag i^n U'd. 8 grams of potassium
absorbed about 22 cub. in. of muriatic acid g^b, ihe tray increased
in weight 6*5 gr. and about 1-Sth of a grain ol muriate was sub-
limed. On wabhmg tht; tray, it lo&t about l-3rd K\i a grain, the
platina having combined with the metal in contact with it.
Hence the potash in the muiiaie conta.ns 9 per cent, more water
than that formed by the combustion of pot<tb&iUm, and Bei thoiiei's
fused potash must contain nearly 23 per cenu of wattr. Jt ap^
pears, indeed, that potash kept tor some time in ar^^J heat contains
l6 or 17 p(^r cent, of water, considtnng the potash trom the coui^
bustion of potussmm as the standard.
Potas&ium and sodium, lannot, tberefore, with propriety, be
considered as compounds, any more than the other meiaJic
bodies.
It has been supposed that nitrogen might possibly consist of
oxygen and hydrogen, or that it might be composed from water;
and its formation has often been announced when none of its
known combinations were concerned: to discover the truth of
these opinions and assertioils, numerous experiments have been
made.
About half a cubic inch of water carefully purged of air, bjr
the air pump or by binling, was inclosed in a glass tube, and de>.
composed by means of 500 double plates, so thai about l-8th of
a cubic inch o\ mixed gasses wt^re produced from 20 to 30 times.
in every day, and detonated witiiout contact of air, the wires
bein a hermetically iiiserted into the tube. After ihe first detona-
Hi'
J
Mr. Dcopi/s new EfsctrOmclieniical Uescariiha. fiSX.
^ioB Uiere was a residuum of l-40th of the volume of thegasses,
this residuum encreased in the succeeding detonations, and when
©boyt 50 had been taken, it was about 1-Sth of a cub. in.; 6
measures of it were found to contain 2*6 ^^ hydrogen, and 3*4 of
nitrogen. When the apparatus was plunged under oil, the resi-
duum did not increase so fast as before ; after 340 explosions, only
0*24 cub. in. of gasses was obtained, b' nieatures of which deto-
nated with 3 of oxveen left a nsiduuui of less than 1 meas. sa
that the residual gas was chiefly hydrogen, which njiglit proceed
from ll.e oxidizement of the platina wires.
To discover whether nitrous acid could be formed in the elcc-
triijation of water, slowly distilled water was electrified in platina
.cones, in a vessel filled with pure oxygen, tl^e cones being con-
nected by filaments of asbestus, and no arid nor alkali was dis-
cover<ible ; even wh n nitrogen was present, the production of acid
or alkaline. n)atter was verj leeble ; but on touching the asbestus
with unwashed hands, or* introducing the smallesi particle of
neutrosaline matter, the j)rf;.luction was immediately evident. In.
other experiments iu wjijch only glas^^, water, quicksilver, and
platina were present, the gasses produced from the water were
collected under quicksilver, and the two portions of water com-
municated directly with each other; tixed alkali was separated,
and* an acid which rendered nitrate of silver turbid. As perfectly
dry common salt is not decomposed by silica, perhaps arid
muriatic acid may exist in glass.
When platina was melte^ by Voltaip electricity in a mixture
of steam and oxygen, no nitric arid was produce(J, unless nitrogen
was also present, and then it was formed.
Steam, passed through ignited oxide of manganese, produced
sufficient nitric acid to render the condensed water disagreably
sour ; it is probable that this methV)d may hereafter be applied
ttt the manufacture of that acid. No acid was produced by
passing the steam over red oxide of lead, but the experiment was
only tried once, and the porcelain tuoe was small.
In order to examine rigorously Woodhouse's experiment of the
production of ammonia from a previously ignited mixture of char-
coal and potash, by the addition of water, one part of pure
potash, and 4 of charcoal were ignited in an iron tube furnished
with stop-cocks, and connected* with a pneumatic apparatus. When
water exhausted of air was brought in contact with this mixture
when perfectly cool, and afterwards distilled from it by a low-
heat, it was found to contain ammonia; the quantity or this
alkali was diminished when the mixture was again ignited, and
was barely sensible in the foqrth repetition. On adding tresji
potash, the mixture yielded ammonia for 2 or 3 successive times,
but when the mixture had ceased to yield ammonia, the power
was hot restored by cooling in contact with the air. Copbider*
No. 24. — VOL. VI, 2 G
/
22^ Mr. DcPCy^s new ^lecfrchchemical ^aearcies*
able more ammonia vfixb produced when a mixture was cooled in
contact with the atmosphere, than when in contact with tb'd
gas produced in' the operation, which is agaiiist the opinion that
nitrogen is produced in ihis( process, bul nothing can be de ter-
minf^d till the' weights of the products are known.
About 1;25 Cub. in. of siioW water that had been boiled, being
frozen and (hawed 16 times successively, ga^ was produced in
ihe first 3 or 4 freezmgs, but afterwards it did hot seeiii 16
Increase; at the end l-50th of a cubical inch of common stir re-
mained. 4 cub. in. of snow water frozeiir 4 times in wrought iroii
yielded l-20th of its' bulk of gas, which contained l-lOth of
oxygen, 3 6f hydrogen, and 6 'bf nitrogen. -
In repeating Kirwari's experiments, 5 cpb. in. of nitrous gas,
and 5 of sulphuretted hydrops n were mixed' over mercury, bnr*
29'b in.; thei m. 51'* Fahr. 12 hours elapsed before any change took
place; a whitish prec'ipit^ite was theifi formed, and deep yellbw liy-
dro-sulphuret of ammonia with excess of sulphur began to appear
in drops in tfie inside of the jAr ; after two days, dnly 2 3 of ga^
femained; bar. 30 45 in. and therm, 52** Fahr. 3«4ths of the gas
was nitrous o.^ide, the remainder was ' inflammable; so tliat
no nitrogen was formed, but only two new compounds, one formed
of nitrogen and hydrogen, with oxygen and sulphur, the other of
nitrogen and oXygen in a more condensed state than b^foi*e. ' •
A Item ptS'Werte also 'hnade to decoibp6uiid nitrogen. With this
viewy about ^ or 3 grams of potassium on a platina cup^
in £ri^out i^ cubic inch of nitrogen, were exposed to the action of
1000 double' plates, ' an intense white light v/as produced, the
potassium was volatilized, and the electricity passing through
its vapour, produced a moHt brilliant flame ; the vapour seemed
to combine with the platina whrrh was thrown otif in smalt
Ijlobuks, as when iron is burned in oxygen. - Hydrogen was
evolved, and sometimes a loss of nitrogen took place, but in. pro^.
portion a^ the potassiuni was freer from a crust of potash, so
much less hyirogen was evolved. When great precautions were
used, the hydrogen did not equal 1 Sth of the volume of gas, an^
no nitrogea was lost. The greatest loss of nitrogen was 1-1 1th
of the quantity used, in this case, the crust of potash was con-
side able, and hydrogen equal to 1.4th of the nitrogen was pro*
duced It therefor^ seems probable, that the nitrogen combines
with nascent hydrogen, and is separated in the gray pyrophoric
sublinrmce which is always produced when potassium is treated
wifh amni'^nia by electricity.
Phofcphiiret of lime conducts electricity, and when placed
between the wires of the great battery burned with a most
iniense light. On being igriittd to whiteness in nitrogen, a little
phosphuretied hydrogen was evolved, but ihe nitrogen was not
altered. ' ' ' " '
t i
I
I I
., ifn Dfftn^s netD Eleetrfy-ckemtcal Retee^ches. 22S
4 > When a. mix iM re of nitrogen aod o?^y muriatic acid gas was
j)assed through an ignited porcelain tube, there was a small loss
of nitrogen, l?ut the, gas came over very cloudv, aqd .the water iii
the apparatus was found to contain nitrpmuriatic aci^..
. The result of th«^se in<|uiri^s do not strengthfn the suspicion
formerly, entertained of .the decomposition of bitiiogen, by the
distillation of the oli,ve substance from potassium t^nd ammpnia
in iron, tub'is, especially as a small quantity ofo;qide might adher^
to tl;ie Vk elded parts, the oxyg.en of which would unite ,with hy-
drogen, from the olive substance, and being condensed in th^
^pper p^rt of the tube, would in the end occa.fion the formation
of ammonia, and probably its absorption, the coi!3equent loss ,of
nitrogen, and increase pif hydrogei). 6 grains of. pptasj^ium in ail
;ron tray, jn a tube used imuiedjately after its interiial surface
had. beep cleaned by, the borer, absorbed nearly l3 cub. in. of
ammonia, and produced about 5, of hydrogen. , About 1 cub. in.
of ammonia, 4 of nitrogen and 8 of hydrogen were evolved in the
first . operation; and 2*5 hydrogen, with I'l^ of qitrogen w^rfc
given, off iii the second ; the potassium produced generated, only
3*1 cub, in. of hydrogen, tt is probable that ,th|s apparent loss
of potassium arose froni,. its becoming alloyed with the iron of
th^ tube ; ^nd in an experiment of ibis kinl, the tube was lined
;with a thiii filni^ of potash j and oh be mg iinhiersed in water^
yielded 2*3 cub^. tn. of hydrogen. , ,. ,
,, From the loss of weight oc(^ui*riHg in the electrical analysis of
kmnionia^it w^s concluded that water or oxygen was separated
in this operation; and lh« production of an amalgam from, ami
monia, which regenerated anjrnoiua, apparently by oxidatiod,
coniivmed the existence of oxygen in t)iis substance. Ammonia
was introduced iqto a glass globe, which had been exhausted afteV
^ing ^lled 2 or 3 times with ammonia, and on being decomposed
by electricity, there wbs no loss of weight, nor any deposition of
hioistufe, but the wires were tariiished, and when brass was lised,
a small quantity <S olive matter formed on the metal, yet
although 8 cub. in. of ammonia were decomposed, the oxide
scarcely affectec( the balance. On reducing the temperature to
15^ there was a feeble indication of by gronietical moisture. The
gas increased from lOO to 185 within a range of 5 parts, •Am} the
hydrogen was to the n«tiogen on the average of 73*74' to 27*26\
Now 100 cub. in. of nitrogen dried by long exposure to potash,
weighed 29^^ gJi^ins, bar. 26'!i in. therm. 61° Fahr. the same
quantity of hydrogen, 227 gr. and of ammonia, 18*4 gr. whence
there was. a loss of from i-12th to 1-lBth in the analysis of am-
monia. This loss of we ght is most probably nothing more than
is to be expected in such delicate processes.
The principal difficulty is to determine the nature of the matter
existihg in ihe amalgahi of ammo.iia, and what is the metallic
\ .
1
2C14 Mr. Davy's iieiv ElectrO'ehemcdi Resedrchesi
basis of ammonia. The anidl^am seems to preserve a quantity
of waiter adhering to it, which inr^y be sutficient to oxi>iise Hak
metal and r^^proju* ^^ the amn onia. The amalgam cannot b^
formed from anunonia in .; dry 5.<i«e The amalgams oi potas-
sium, sodium, or bariu;n, do not prodice it iA ammoniHcai gas^
and when heated with murine of ammonia, the alkali is nqt
metallized, unless the salt is moistt. When ammonia is acted
upon by metallic amalgams negntively electrified, the effect is less
distinct than with pure quicksilver. Quicksilver exposed to *2(/*
Fahr. yielded a more scMid amalgam than uswal, but it decomposed
as rapidly as the comnion, and yielded more gas, so that once G
times its volume were obtained. The solid ariialgam of potas-
sium quicksilver and ammonium, can probabhy be obtained the
freest from adhering moisture, it decompos s very slpwly^ evenf
in contact with water, and when well \t'iped it bears- a consider-
able heat without altfration. When strongly heated in a green
glass* tube filled with hydrogf^n, ammonia is partly regenerated/but
with this ammonia there is from 5 to6-10ths of hydrogen pro.
duced. On account of th^Tvariation in the moisture, it is difficult
to determine the ratio that would exist between the hydrogen
and ammonia if no more water were presciit than would be de-
composed iu oxidising the basis. It was never less than 1 to 2,
and often more; whence^ supposing ammonia to be an oxide, it
hutst contain about 48 per cent of oxygen. Even in common*
air, the amalgam evolves hydrogen and ammonia nearly in those
proportions, atid il does not appear to absorb oxygen from !he
air, for although the air to which it had been exposed^ was for-
merly tound to give less diminution with nitrous gas than before,'
this differencie might have arisen from tlie mixture of hydrogen.
If hydrogen be supposed a simple body, and nitrogen an oxide",
this last Would consist of nearly 48 oxygen and 34 basis ; but if
liydfogen and nitrogen arfi both oxides of the. same metal, then
liitrogcii contains less oxygen. But, if \iie facts co?ncerning am-
monia are considered, abstractedly from tffe other general phe-
liomena of chemistry, iliey are best explained on the liotiou
of nitrogen » being a basis which becomes alkaline by one dose of
hydrogen, and metallic by a greater proportion.
The proportion of matter added tt) the quicksilver in the
amalgam was stated as l-r200Qth part, on' the supposition, that
the quicksilver gave off only 1*5 its volume ofam:iionia, which i^
the minioiuiu.. Oin the preceeding statement of 6 times its balk;
the amalgam will, >n the antiphlogistic hypothesis, contuio about
l-1600th of ne.w matter, and on the /^A/og^^/c, about i-gOOth.
As to the metallizatiou of the earths. When iron was nega-
tively electrified by 10()0 double plates and malted in contact
with silex, alumine, or glycine slightly moistened and placed ia
.»|*iB^sp-5r.,:;'?:>^4^.
■-."tfaE
A
Mr, t)axi/snew Eleetro^chemcal Resedrckes, f 25
fcydrdgen, the iron berame brittle, and whiter, and deposited the
fcarib on solution in an acid.
*Fonr grains <»f potassium sublimed through 10 gr. of silex#
heated to whiteness :n a platimi tube, evolved no other gas, hut
"what might be referred to moisture adherent to the crust ofpotashc
The potassium was entirely destroyed, and glass with excess of
alkali was obtained ; this on being powdered, exhibited dark
•pecks, of a dull metallic appearance ; on being flung into wat^r^
there was only a slight effr^rvescenre, but on adding muriatic acid,
gas was slowly disengaged, so that it is probable the silex had
been disoxygenised, and was slowly reproduced. 6 gr. of polasr
sium, and 4 gr. of silex being employed, a part of the result took
fire as it was taken out of the tube and left alkali and silex, the
part that did not take fire was similar to that obtained in the
preceding experiment.
Potassium acting upon alumine and glycine, produced more
hydrogen than could be ascribed to the crust of potash, so that
it is probable that they contain water, although previously ignited.
The residuums were dark gray pyrophori, which emitted brilliant
sparks when burned, and left alkali and earth. They were rapidly
decomposed by water. When naphtha was introduced into the
tube in order to prevent their combustion, they were found to be
very friable mabses, with small • metallic particles which melted
in boiling naphtha.
On introducing quicksilver, while the tube was hot, and the
potassium in excess, amalgams were obtained, but they resembled
the alkaline amalgams, and although a white matter separated
from those of glycine and alumine, during the action of muriatic
lieid upon the atiiaigam, yet the existence of the metals of the
earths in them was very doubtful.
Mixtures of the e&rths, potassium and ironfilings being ignited,
whiter and harder metallic alloys of iron were obtained, which,
when treated with acids afforded the earths made use of. The
alloy from silex was brittle and crystaUine, from alumine and
glycine imperfectly malleable.
Solid amalgams were obtained by passing potassium through
lime and magnesia, and that from magnesia was easily deprived
tf its potassium by means of water; the amalgam was then
"white, and when exposed to the air, hecan)e covered with a
dry white powder ; treated withjrnuriatic acid, it yielded hydrogen,
And produced a solution of magnesia.
It is probable that these alloys of the common earths may bo
formed iri metallurgical operations, and that small quantities, nt
them n^ay Infiueace the pro^perties of the compouud in which
they exisrt^ thus Berzelius says that copper is hardcoi^d by
it^-^k: _ ' '■' ^*
-"H
5^5 3f/% Dax^ys new Blecira-chimkal ResedrcM.
If we allow the attraction of acids to salifiable bases to U
inversely as the quantities of oxygen that they contain, and thai
this attraction may be measured by the quantitieb of bases whicli
any-^cid dissolves, it would be easy to infer the compositioD of
the base. On the faith of the most accurate analyses ot the
tieutral salts, bavytes must contain 90 5 per rent of metal, btron-
tites 86, lime 73*3, magnesia 65, and alumine about 56. Bewe-
lius says he found silicium in cast iron, and that on being oxi-
dized It took up nearly half its weight of oxygen. On the prin-
ciple just stated, silicium ought to contain the largest pioportioi^
of oxygen, and ammonia should Contain 63 per cent of metallic
matter, and 47 of oxygen.
The alkalies, earths, and oxides have been generally cof.MHerej(
as separate natural orders, but the more the sul»jt'ct i? ♦^nquire*!
into, the more distinct will the general relatiuti of all uifiallic
Substances appear.
Hydrogen combines with the lara^est proportion of ox\^en, and
^et forms a neutral body, so that it should he tinhui inore ut^, 1y
positive than any other body, and if an uxai. , not i k^ lobe
decomposed by simple attraction. As it forms a bubataiuv a[>:
preaching to an acid when combined with telluriunr^ or 5ui)»hur,
it is probably neither a gaseous metal, nor simple; nor exists m
its Common form in amalgam of ammonia. And ,when in lutro*
inuriatic acid, the nitrous acid is decomposed to form a metallic
muriate, nitrous gas, a bod} highly oxygenised, is emitted.
If hydrogen is found to be protoxide ot ammonium, ammonia
the deutoxide, and nitrogen the tritoxide, the theiwy of chemi&try
would be simple, and the existing arrangements >vould harmonize
iK'ith all the new facts; but explanations may be found, which, if
not so simple, account for the phenomena, with at least equal
tacility. Hydrogen may be considered as the principle ol in-
flammability i the cause of metalliaation, and with oxygen the
only simple body. Metals and inflammables as compounds of
hydrogen and unknown bases, the earths, fixed alkalies, metallip
oxides and common acids as t-ompounds of those bases witb^
water.
The properties which seem to be inherent in certain bodiesy^
and which are either developed or concealed according to the
nature of their combinations is a strong argumept in mvour of
the last notion. So also is the greater facility with which oxides
are reduced when hydrogen is present; thus,' when fused litharge
%»^ as electrified by 600 double plates, there was effervescence at
the positive side, and a black matter formed at the negative, yet
tio lead was produced ; but when nwistened litharge, or a solution
of lead was eiaploycd, the metal was rapidly formed- Again, hy-
drogen and ox^'^en seem in oil ca^eaf to Aeutraiise dach oibe£»
f
iir. T^cccyU new E(e(fro*ciemkaI 'Researchei'. 2^7
and of course should, as is really the case, most distinctly dis*
play, in combustion, the mutual ^^nergy of the bases.
' Potassium, sodium, and all metals hitherto tried, evolve the
same qunrtity of hydrogen, when treated with niuriatic acid ga?»,
*and all form dry muriates, so that if the existence of water in the
potash f rmed in muriattc acid gas be allowed, it must also exist
in the oxido^ of metals tormed m similar operations.
The difficulty of finding any multiple quantity of oxygen which
may he supposed to exist in hydrogen, that' might be applied ta
Explain the comp«»siti6n of nitrogen from the same basis, is
against thte antiphlogistic view of the subject; but the compo-
sition of the tnetal of ammonia from hydrogen and nitrogen, or
'of a metallic sulislance, from substances not metallic, is equally
contrary to the general tertour of chemical reasoning.
i ■..'...■■
I ■ ■Hill
The electrisation of sulphur and phosphorus goes far to prove
that they contain combioed hydrogen. From the phenomena
they exhibit with pt»tussium; they seem to contain bxyged, parti-*
tularly the vividrtess of the ignition, but tellurium and arsenic
Txhibit the same phenomenon.' I'he phenomena in the action
of potassium upon stilphur and phosphorus, Sulphuretted and
phosphu retted hydrogen vary 'accoraing to circumstanws, and ^
Sometimes potassium 'yields more gas after it has been exposed to
these bodies "than it would give alone; That sulphur and pbos«
pborus are nonconductors of electricity is" one evidence of their
containing oxygen. * Potassium and sodium heated in hydrogen
inixed with atnibspheric air", iabsorb both oxygen and hydrogen,
^ivi become nonconductors i
When sulphuretted hydrogen is decomposed by common elec-
tricity, its volume is slightly diminislied, and the sulphur is
whitish ; by Voltaic electricity, its volume is net altered, and the
^ilpliur is as usuhI ; hence il it weighs 35 gr. per 100 cub. in. it
will conrain $*27 of hydrogen, and 34*73 of sulohur. When ar-
' geniur^tted and phosphui^eltcd hydrogen were decomposed by elec-
tricity, their volume was not changed, the phosphoras however,
was dark coloured, and the arsenic brown. Wh«m a small qoan».
tity of potassium a'ts upon these gases, their volume is expanded,
so that it is pn>bable they contain in equal volumes, more hydro-
gen than sulphuretted hydrogen. 100 cub. in. of pho^phuretted
bydrVigen weighs about 10 gr. at a mean temperature and pressure,
und the same volume of arseniuretted tiydrogen, about 15 grains;
Ohservaf ions, -^The preceding iidkenan lecture, although it H'ds
considerably to our knowledge of the subjects oper-ited up«»n, » oes
fiot altogether remove the dithculty which embarrasses the opmionti
that may be formed f expecting their composition.
^
ddS Mr. Daa^$ neu> Ettctrohchemical Ruearckti.
Mr. Davy treats Ritter's argumeut concerning the lightness of
the new metals^ being io favour of their containing hydrogeni
with great disdain, and informs us, that '* no one^ is more easily
answered ;" l|ut it would have been better to have entered some-
what more psirticularly than he has done, into its confutJitioD.
According to our conception of Weiss's account of Ritter's disco^
veries, of which an abstract w«s given in our last volume, and
the continuation of it in the present number, Ritter observing
that the oxides of the common metals are all speciSeally lightfr
than the metals theuisfJves, as might be conceived from their
union with a lighter substance, viz. oxygen, was led to suppose,
that as the tixed alkalies are specifically heavier than the metaU
produced from them, it was improbable, that they were the ox-
ides ot those metals, but that the latter were more probably a
combination of the alkalies with some lighter substance, namely,
hydrogen. Ap argument which certainlj^ appears, at first sight,
to possess considerable force : for although the specific gravity
ef a compound is not exactly the mean of that of its constituent
ingredients, yet, that a compound should be much denser than
the densest of \U ingredients, is certainly a very rare case.
Bat is this rare case that of the supposed compounds in quee-i
tioo ? is oxyg/en, coiiisidered as a solid, less dense than soda or
potass ? We answer, probably not. Let the weights m and n of
two substauces, having the specific gravities a and 6, be mixed
together, setting aside the consideration of any condensation:
then the joint bulk of the compound will be — h t ~ \
and its specific gravity, being represented by the weight divided
by the bulk, will be — zz c, and (m + n) ab zz mbQ
MO -\- na
4- naCy whence b z^ . Now let its suppose,
■ ' {m -J- 7/) o — . fttC ^ rf y
that th® specific gravities of oxygen and hydrogen, as they exist
ill water, are in the same proportion as in the gaseous state, 4hat
)s, nearly as 14 to I; then m being 6 , » J, c i, and a zz: I4bp we
I 20
liave gSbb zz: 6b + 14, 986 =z 50, * = 77 , and ba zz -z
zz: 2'S6 for the specific gravity of oxygen : or if we make th^
disprofiortion but half as great, and a =;= 73, then 49 bbzzbb + 7^*
J 3 ]3
6 zz — , and a zz — zz rS6'. We have, howevier, a more di-
' 49 7 • '
rect mode of computation from the specific gravity of the vitre-
ous oxide of antimony, which is 4*93, while that of the metal is
6*^99 the proportion «»f its con)ponent parts being nearly that o(
100 to 23: her€ m =z IQO, n zz 23, a zz 6 89, and c == 4 95,
#*
whence 6 is founxl 2*23. And^n the whole,' allowing fortsome
.iincerttainty in the elements of the calculation, it .is highly pro.
bable, that the specific gravity of solid oxygen eugbt to be e»ti«
inated as being within the limits of 3 and 2*5. But Hassenfraie
tnakes that of soda only 1*^4 ; and we may fairly set dowu the
Specific gravity both of potash and of soda as decidedly lower
than 2, It is true, that there must still be a very considei-able
condensation during the conversion of .potassium into potass by
'Combastiofi. Bur where -is the improbability that a great coiu
idensation should be the effect of a very violent attraction ?
Mr. Dayy, in eomnioh with the greater m|mber of moderik
^authors, at'vi'ays lis^s the epithet ^* phlogistic" to denominate the
theory in which hydn^n is held to be the principle uf intiam.
ifnabiiity ; but this denomination does not appear to us to be
Strictly accurate. I'he phlogistic hypothesis properly denotes
the common theory of combustion of the oldest chemists, in which
the phenbtnena of inflammatiow, A:c. were explained by the escupe of
an unponderahle fluid, under the names of light, iire, piilogist«)n,
or some similar appellation, and which, as Stahl was the iir$t
elementary aulhor on general chemistry, who shewed the full
extent of its application, is called frJom him, the theory of Stahl.
Lavoisier appropriating to himself the discoveries of Hook and
*Bayen; attempted to overturn this doctrine, and establish his
own antiphlogistic system on its ruins. One of his opponents,
Kirwan; took as it were a middle course, and- conceived. hydrogen
to be the principle of iiifl-ammability ; but although this was in
'opposition to the antiphlogistic system, it still differed essentially
from the older Stahlian doctrine, and should not be called by the
'^ame naUtte*.
JM i,i__LlL- ! I ■ "I '■ .Iji H 1 ■! 1. J, .' » .i. .f
Anaiysis pf Augite^ Mtlanite, Staurotide, Labrador Hornblende,
shifrloijts ^Beril^ reddish -Muratian Tourmaline , S^ Mr, Klap-
KOTH. ^^Annales de Chimie,
Black atrgifte (pyroxene or volcanic schorl) is found in very
£ne crystals in the fissures of Mont Latin near Home, and in the
'neighbourhood of Fratcati. It is easy to break, and the tritu-
rated' powder is greenish gray* its s^cific gravity is 2, and the
' bldwpipe merely founds the comers and edges. It does not meit
With twice its weight of carustic potash, but merely forms a
broMTn mass which gives to water a light green colouri*
• Til is augite contains 48 per cent of silica, 24 of lime, 8 '75. o£
knagnesia, 5 of ahimine, 12: of oxide of iron, 1 of oxide of m^angsi-
inese, 8k)me traces of potash, and^ r-25 were lost; Mrhich analysis
^pp roaches. very near to the^tatiementof Vanqueliu.
■^ '-Melamte ,(black. gatrneO ^ives a brawnish or blackkh. gray
Ko. 2-i.— Vol, VI. 2 h ^
J
£4.
!Ufd Mr. Klaprtdh's jlnMym o/Ju^e; iitkmtt. ^i.
powder. Us 8(»ecific gr -vity is 3'7. It undergoes scares Sttt
alteriition when ignited in a cracible, but the blowpipe reduces U
slowly to a pearL It contains 35*5 per cent of silica, 32*5 d
lime, 6 ot duMiine, 24'25 of oxide (»t iron^ 0*4 of ox\6e oi inatv-
ganese, and 1*35 were lost; which analysis is conibrmable i&
that ot Vatjqueiin.
The analysis lormerlv made of 'pyrop, or Bohemian garnft^
has been quoted in several French books^ as being that of meh^
Bite. 1 hore has been iound iu Boh«mian garnet 2 per ceni. d
chromic acid.
Black staurolite (grenatite) from Saint Gothard is deep brown*
isb black, in large or titiddie size cryt^taU, ahiiost alHong, which
are eitrier imbedrled b(»litarily, or intersect each other in the iorm
of a Sa.nt Andrew'b cro&s. The surlace is fine grained, but al-
most always scaly ; it id bin slightly briKiaot externally, in tli«
internal parts, the Instr^ vaiiPS accordiitg to the grain, being
either "very brilliant, or between resinous and adamantine, its
specific giavitv is 3*51. it is not changed in colour, weight, or
form b\ calcination. It was found to contain 37*5 per cent of
silica. 41 of alumiue, i8 26 of oxide of iron, 0*5 of magnesia, 0*5
of ox ie of manganese, and 2*25 were. lost.
Reo staurotide varies from brownish red to reddish brown ; it
Is usual iv iuirulated in mica slate on Mount St. Gothard, and
very rarely crossed. Its surface is smooth, and its lustre rather
resinous. It is trequently crystallized along with kyanite, so
closely that they appear only one substatKe ; in this ease, the
i^taurotide is slightly traru^iucid at the end of the prism Its spe-
cific ^avity is 3*7^)5, ami it contains 2? per cent of silica, 52'2d
of aiumme, 1&*5 of oxide of iron, 0*25 of oxide of manganese,
and 2 veie lost.
Brown staurotide of Quimper in Morbihan, and that of Finis,
ierre connect the two former varieties. This variety is usually
found in rectangular or obliquangular crosses; both the prisms
ilire trequently of the same s ze, but one is sometimes much less/
and appears to have been imbedded in the other.
Lab ador hornblende was formerly confounded l>y. Uaay with
metalloid oiallage, or bronzite, but he lias siiice made it a dii-
tin( > .>{>ecies under the name of hyperstene, in reference to its
superior haidtiess, and specific gravity, when compared with
borobl^nfie. Its colour is n^aroon brown p, assing to brownish
blaick, internally it has resplendent spots whose brightness is
augm'^rred by being poiisbed and whose colour is a medium
between 0(»pp«r brown, pinchbeck brown, and gold yellow. At
pi*esent it has only been found in fragments, so that its form is
uj)known. It has a semimetallic lustre^ is very distinctly lamel-
lar, ^^^ ^^ fiakes cross each other in two directions, at angles of
^(f aitti. iOO^ It breaks into l^eof^ «hftpe fragment. It is
.3>. Kfaproih's Jnah/m ofAvgUe, Melanite^ SfC. tSl
•pake, aud yields greenish white scrapings. Its specific gravity
16 3.390. It is not fusible by the blowpipe, but iis seminietallic
lustie turns blackish. The {lewder of tfaid stone beings; calcined,
k^fees^one per cent, of iis weight, and becomes of a deep a&h gray
colour. Jt contains 54*^5 per cent, of silica, 14 of magnesia,
2' 25 of alumine', 1*5 of lime, 24*5 of oxide j>f iron, I of water,
6ome traces of oxitte of manganese, and 2*6 .were lost.
The analysi? of the ^iaagenst«in, orpyenite of Hauy» fo^pd at
Al ten berg, mixed with quariz and nuca, formerly made, was
y€sry supeificial, and does- not deserve Twuh consid«*ratioii ; the
stone has therefore been analysed atres'h, partly tu find it it c»n-
tained any glycine, because it had lately been called by the name
4>f chorions beryl. It diHPeis, howevei, vf*ry ranch from beryl,
which loses one fourth of its weiglit, so that it has a greater ana-
logy to topaz. Bncholz first discovered that this loss was owing
to Huoric acid, which has been confirmed by V'anquelin, who
found 3^5 per cent, of lime in this stone, (the editors of the Aii-
nales add in a note, that the specimen examined by Vauquelin
tvas not pure): this has not been observed by others. Bern-
hardi has made several rnineralogical observations, which concur
in shewing that it sht-nld rather be called schorlous topaz.
This stc»ne, heated in a crucible, yielded a whitish vapour, but
it underwent very litlle change, and lost only one per cent, la
the porcelain furnace it became gray, dull, and rough on the sur-
Ikce, with a very considerable l(»ss of weight. On being distilled
in a luted glass retort, il yielded only clear water, which did
not redden litmus paper; but on distillation with once and an
half as much sulphuric acid, the neck of the retort was corroded,
atid a moist siliceous sublimate was obtained, but not so abtm^
dantly as from topaz. On analysis the stone was found to con«
tain 43 p«^r cent, of silica, 49*6 of aumine, 1 of, oxide of iron ;
ao that allowine; I. as above, fnr the water, and I'A- for the
«isiial inevitable loss, it should contain about 4 per cent, of fluoric
acid.
Th€ reddish prismatic or needle like stone found in Mount
Hradisco, near Roczna, in Moravia, imbedded in corppact with-
t3b gray quartz, or m lepidtilite is peacii flower red, verging in
«<>me places to greenish yellow, and white gray. As it ks found
immediately • under the lepidolite, Ebtiier has descrit>ed it under
the name of crystallized lepidolite ; but as it differs ^y its cbe*
mical characters, it was afterwards considered as schorlous beryl
or stangenstem. Hauy arranges it with the red Siberian schorl
<>r siberite, under the name of tourmaline apyre, as it is not fusi-
ble by the blowpipe upon charcoal, but merely becomes chalk
■whitfi. Heated in a crucible, it loses 1*25 per cent of its weight,
with scarcely any other alteration. It contains 4^*5 per cent, of
silica, 4i3^25 of alumiue, i*^ gf oxide of mapganese,.0-l of lime.
■^^
232 Dr. John's Analysis of Minerak.
S of soda, l*Q5 of watt-r, and *2 4 were lost ; hence. Hauy i? coni*
plettl^ justi^N'd in his classing it with siberite, which, accordiug
to n i^le analysis by \'&\ qudm, contains 42 per c^nt. of silica^
iO r: aluniitit, 7 of slightly ferruginous <^xidc of manganese, iCf
of soda, while 1 was lost.
.^^xx.
Analysis of' some Minerals knotcn hy the Is^ame of Talc. By Dr.
JoH^i. '^Annalcs de Chimie, loL 67.
Wii^K INiitchel gav^ the name of magnesia to the carbonate of
magnesia foynd at Rovina in Moravia, it became necessary to de-
signate the mineral which Werner had described in his translalioo
of Cronsledt, by another name, and the name of earthy talc was
applied to it. Vauquelin has given an analysis of a mineral un.
der this name, in which he found no traces of magnesia; but as
the sam^ name frequently denotes different minerals in France and
Germany, it became necessary to examine the authentic speci-
mens described by Ileuss, in his new system according to Wer-
ner.
White earthy talc, of f reyburgh in Saxony, is little affected by
the blowpipe, but at length it melts in some degree, and the point
of the flame in contact with it, is tinged of a fine sapphire blu^
colour. Microsmic salt dissolves very little of it. Glass of bo^
rax dissolves a very large quantity with great ease. Heated in a
crucible, it was not altered, but it lost 13'5 per cent of its weight-
'it is soluble in nitric or muriatic acid, without any efl'ervescence v
the concentrated solutions take, on cooling, the form of a firm:
jelly. Concentrated sulphuric acid, forms i combination resem-
bling starch glue ; when water is added, a solutioiji takes place^
and a little sulphate of lime is left. It contains 81*75 of alumine,
13 5 of water, 0'7q of magnesia, 4 of lime, and 0*4 of potash ; so.
thai the* e was an excess of 0 4 part. These results are sur-
prizing, and t(ie mineral must be looked upon as native alumine,
even purer tli an that found at Hall.
Yellow earthy talc of htiefelburg, near Merow/itz, in Bohemia,
was calcined by the blowpipe to brownish red, but did not melt.
It dissolved in borax and microscosmic salt ; the pearls were
transparent, and yellow when hot, but lost their colour by cooling.
Hiaied in a crucible, it became cinnamon colour, and lost
5 per cent of its weight. Nitric or muriatic acid act very
slowly upon this stone. Nitromuriatic acid takes away its colour
without diminishing its lustre or greasiness. The acids take up-
a little alumine an<i iron, Siilphuric acid does not diss<»lve it.
Heated wi»h soda, it forms a grayish substance which does not
melt in a silver crucible, but is completely ^»luble in water; this
solution being supersaturated with muriatic acid becaxBe clear,*
J/r. Buriecjf o» the Profiis of Wilt^ire Menno Crcss'-Sheqy. 23;Sf
^od when rvapora*ed exhibits the presence of siUca. It.contains
'jG0*2 per cent (*r silica, 3Q*83 of alu'iin's !i 55 of oxide of iron, 5
of water, some tiaces ot ii ise, and 0 -42 ^vere lost.
Ironi these analyses il aj'jien!^, tiiJit neither of these minerals
can any long'T be let in the niaj.n ^an genus, if any regard is
to be paid to ihe conbtituont pa! ts of fobSils in their arrange-
ment.
OAsTrivz^o//.?.-— ilo'vever swrpU/pd Mr Bucholz, who communi-
catfJ this |- '.^jt;.-. .nay iMvf l'«en, we see nothing in it to excite
aiiy w« iiut-r. i i*<- soiifr niHU-Mils of- the class of earths in the
system ot Werner have always app^-arrd to us a mere mass of the
mobt inextncabl« cont4isi«ii. Indeed ^ve iiave little or no hesita-
tion in siying, t4jdt, aLbo'^b our knowledge of stones has been
gjieatly increased of l^te, the earths, as they are commonly called,
have been as much neglected, and our knowledge of them has
been in a reiograde state ever since the method of distinguishing
them by their habitudes, with the blowpipe and acids, assKetched
out by.Cron&tedt, has b^en negleeted by the Weruian School.
'. ""^ ■ ■<" ■ ji i . I I ■■■...■■u .11 ■ .^^
AGRICULTURE.
On the comparafixe Profits of JViltshlre Merino^cross SAcep, By
JVloKRis BiRKiiECK, «/' IVurborouj^hy iii Surny — ^^ricutiuraf
Magazine y No, 33.
Mb.. Birkbeck states, that he exhibited at Lord Somerville't
j^ttle show last spring, five Wiltshire wethers, and three quarter
lyieriqo wethers, both of \Vhich lots were taken into keeping on
the 30th of November, I8O9, and seiit to be exhibtted the *2nd of
March, 1810; they were all kept on hav, lu.nips, and oilfcake.
.fhe Wiltshires weighed in November, 8 I7lb., and increased iu
ihe 13 weeks of the experiment, 182ib, which, at 8d. per lb.,
amounts to 6l. is. 4d., and ^s. 9d. is allowed forHhe growth oi
wool ; and the cost of iheir U^ud during the time, was 7l* 14s. 2d.,
90 that the loss was ll. 4s. Id. The Merino-cross sheep weighed
\ii Novemb«»r, i?37lb., and gamed in th** same 13 weeks, 133lb.,
which, at 8d. per lb., amounts to 41. 8s. 4., and IL 5s. is al-
lowed for the growth o\ wool ; and the cost oi their iood during
the time, was 4<l. ISs. 2d., lea>ing a profit of I5b. 2d, The mfe-^
pence drawn from this experiment, is, that the tood which wa»
coiisuuied by the large sheep, would i»ave produced /ottr^ww per
ttstf n*ore in absolute weight of mntion if consumed by the small
y,heep, besides the ditiereuce in the value of the wool, and the price
234 Mr. Hardy on the XjrWwti of Turnips in the Island of Jersey.
of the mutton. The Wiltshire mutton was sold in Newgate mar-
ket, on the 5lh of March, at 6s. 8d. per stone ; fuad the Merino,
ihe sa,me duy, at 7^. per stone.
Observations. ^^This experiment seems to have been made with
eqaal tdirne s and accuracy, and the inference is ^uUy w.4rrante(l
by the premises , but it is conceived, that the growth of the Me^
rino-cross wool is valued too high at ll. 5$^ since that value
would e€|ual the value of the produce of pure Mineros.
On the Culture of Pc^rwips in the Island of Jersey ^ and their Utility
infetdln^Cattk. B^ Chakl^s {^b IIardt, E.squire*
The most regular crops in the island of Jersey, are stated to be *
ebcans and parsnips, which are cttltivated by every farmer, for the
^ jxnrpose of fattening bis hogs and cattle, and of feeding his milch
pows, and though parsnips had for a few ^ears given way to po- -
tatoes, yet further experieiice has bi ought the farmers back again
to their former practice ; for though the produce of the potatoe
is greater, and the ex pence of its cultivation less, yet it is not
found to be really so nptritious as the parsnip. 1 his root thrives
almost any where, bttt best in a deep stiif ioam, and is generally
sown after barley ; the soil is either dug with, a ftpade after a
skimming plough, or stirred with two ploughs of ditferent shapes
following one another^ for tiie soil ft)r this pi^rpose nnust be stir,
red from the bottom, and a ph)uoh is made for this sole purpose,
which will go to- a depth of fttteeii inches. This operation takes
place iir January or February. The ground tilled m this way, is
coarsely harrowed, and Leans aie dibbled by women in rows ^ve
feet asunder, and the parsnip seed is then st»wn broad cast, and
the whole finely harrowed. In May the ground is carefully
weeded, both <>y hand and vyith a small weeding fork, and the
hand-hoe to thin the crop, like turnips, has been used with advan«
Xage. In the beginning of September the beans are pulled fronj
the parsnips, and about the latter end, these also begin to be dug
up, but are only taken as wanted for the cattle, till the ground re-
quires to be cleared for sowing wheat, which is gienerally by the mid*
die of December. The unconsumed part of the crop is then brought
dry under sheds, and will keep good without any care to the tn6
of March ; but if they are to be kept longer, they are stacked in
double rows, one over another, with their heads outwards, with
alternate layers of earth; and this method is always adopted for
thobe intended for seed, and for culinary purposes : they are not
injured by frost, and will vegetate alter being frozen. They are
given raw with advantage to hogs and horned cattle; but the^
Tender l^orses langnid, an4 are apt to injure their sight. Cows
J
ilff/or Cochrane on the Properties of Furze and tVhms. 2S5
fi^ upon parsni{>s in the winter months, are said to produce a
greater quantity of milk and butter, and of better flavour than
wheii fed upon potatoes, but the leaves must not \t used, as they
give a very disagreeable taste ; they are considered dangerous
Food for sows before they farrow, but hogs may be fattened with
them in about six weeks, and they aie sometimes given to sheep
for the same purpose. It is a general opinion^ that all cattle may
be made fit for slaughtering in less time, and with half the quan-
tity that would be required of potatoes ; the butchers give more
for them iu proportion to their weight, and they always contain a
greater quantity of tallow.
Observations. ''^^Yii^ communication respecting the culture and
Use of the parsnip, is one of the most valuable which has appeared
ip the magazine feu* a long time, and is highly deserving the at-^
tention of agriculturists in this country, where it might be culti-
vated with nearly equal advantage, by consulting the difference of
tlimaie; VVe strongly recommend the trial.
On the properties of Furze and Whins^ By Major Spencer
Cochrane, of MarsHeld Home^ North Britain^ — Agricultural
Magazitiey No* 33*
The writer^ bonceiving that though the utility of whins or
furze, as a food for cattle^ has been long knpwn, yet its value as
a medicine had not been duly appreciated^ stales,, that a relation
of his, who has been an officei of the army, and now enjoys
good health, at seventy five years of age, informs him, that his
feight had been much strengthened by drinking an infusion of
furze blossoms, dried in the sun in summer; the infusion was
made from a cup-ful of the blossoms in a teapot, in the sam^ manner
as tea, and the dose half a tumbler at night, which acted as a diu*
retic and by perspiration, and when increased, promoted sleep.
It is also stated, that the same gentleman, when on military
Service in Ireland, in a poor village, which afforded neither
bran nor malt for mashes, preserved all the horses of his troop
by giving them 'furze, cut and beat on a pavement, being at
first mixed with oats to induce the horses to eat it, at a time
when an epidemic cold prevailed through«ut the. regiment, and
desjtroyed many horses in other troops, aud that his was the only
troop in good condition at the review.
ObtetvatibtiU'^The utility of furze, both in blossom, and the
tops of tbfi plaata, bas been ionjg^tiSed as aniedkine in the
s .
iSG . 'Major Cochrant m the ProptrtU$ of Futze and WMns^
Northern couu lies, as a sudorilic in colu- .^.u iou{e:bs ; und th^
inloitnation roainiutucated in il is pa| • • se* . b u>(onhtDiihe
inference by • aiiai«jgy, that it will pruuucc bituxlar etkctt, when'
iidmiuistered to hordes;
ERRATA
iN OUR La&T numszr.
1*. i^y I. 29, omit. It should — mixumudi:
S6, 1 5, for ten re^d fourteen ;
6, for 12, read 8;
9 fbr five read sevfcti;
.. 1. > . .JMi
-i^^fci^ ji 1 1 ■
M^
iVb. JtXKviU bef^liihed Niottmb^ 1, 1810«
**
RETROSPECT
*•*:• J
■
OP
PHILOSOPHICAL, MECHANICAL,
CHEMICAL AND AGRICULTURAL
DISCOVERIES.
iBS-aMi
±
- No, XXV.] July^ August^ September,
mmmmesi
[ISLO.
CHEMISTRY and MINERALOGY.
On the Urine ^Camels, and that of Horses ; atid on the Uric Acid in
. the Excrenients of' Birds, By Mr, Chevreul. — Amudes de
Chimief vol bj,
1M[r. Brandt having announced the discovery of phoephate of
lime in th«i urine of herbivorous animals, and that of nric acid inf
^e urine of the camel, it became necessary to examine theM
statements.
The urine of the camel, even when quite fresh, contains carbo-
nate of ammonia, for it e^ervesces with acids, and white vapours
are produced when a substance impregnated with muriatic acid
is brought nigh it. When distilled, it grows turbid, deposits m
Cray, earthy sediment ; and there comes over, carbonate of am.
nibnia, and a volatile oil, which gives it a peculiar smell, and the
property of becoming rose-coloured when mixed with sulphuric^
nitric, or muriatic acids.
The tirine remaining in the distilling vessel, was filtered and
^fivided into two equal portions.* The first was eviaporated to
the consistence of honey, and formed a very dirty brown ex**
tract, totally soluble in water. Oil distilling this extract, it
melted, and there passed over carbonate of ammonia ; pnissiate
oTamniibnia recognised by suspending a skain of cotton impreg- ,
Bated with green sulphate of iron in. the receiver for a few mi-
liutas, and then dipping it into water acidulated with sulphuric
acid» which turned it blue ; citron yellow oil, composed of oil of
I)ipp'el, prussit acid, and ammonia; brownf yellow oil; asttlphu^
reous very bitter charcoal remained, which yielded by elixatioD,
• ' No. 25.— Vol. vi. 2 i
238
Mr. Chtvreul on tie Excrements of Birds, SfC.
hvdroguretted sulphuret of pofash, and a large quantity of pm--
Ste The water employed to wash the volatile prodacts w^;
examined by solution of silver, and no traces of munat.c acid
^er™discovered, so that camel's urme does not contam munaf
of ammonia, or at least a very mmute quantity.
The arav earthy sediment above mentioned effervesced with
aciaS was divided into two parts.- One was « kmed and
dW not S»n effervesce wtti nitric acidl but a small quantity of
charcoal was %arated. Tha solution was rendered turbid by
ammonia, and was found to contain silica, magnesia; Ume, and
sle tram of iron : it is evident that the silica must have been
some n aces oiir otherwise have been so-
S inth a?.d The other portiin was digested in-pure potash
lut)le m tne/c'"- ., , j[ ^ was not rendered turbid by
^"^runtS^f days w ve e^^^^^^^^ which showed thatthisre-
acids, until s«'"^> f ^>' „ric acid; This,alkaline liquor super-
?r t/dwUh aS wa7evi^^^^ ^ dryness, and afterwards
Saturated wUh acid was V ^^^ ^^^^^^ ^„j ^^ ^
mixed with >«'« ^^^^^ ' p7eLt; neither was the magnesia already
no Pho^Ph^lf ^ 'J^^^Xt fin the state of a phosphate. So that
discovered ifl ^^\^l°'^'j^ ^{ ^ small quantity of animal matter,'
£^;rn"f-"-^-«^»^ ^' ^^*^''""
and a ""«"*« P^y*';h\he"above substances had been separated by
TJrine from-which^tne a formed a crystalline mass
concentration was evaporated uni being poured upon tfils
on being <=°«l*='l- ,.;f,\twn and o„ /eing distife yielded a spi.
„ass became redd^hbro^n ana g^^. ^j ^^^^^^^,
tit impregnated with <=^I°~t ^hi^h remained ^as treated
from <le--P"^f "^!" to eVpel S alkohol. Dilute sulphuric
tvith water, and 1>«^*^° ,'° .^^^benzoic acid, which became white
^id threw 'i-;" - ^ f "^t Set being then distilled, yield-
on being twice suWimed in ^^^ ^^^^ ^^^^^^ ^.^^
ed a small q»^"^f y f 'J":tLf of urea, whieh, on being separated
acid, yielded crystallized nitrate «^ 'evaporation, redfoily pelli-
from the liquor, yielded o«^ <=^^^^. J^^, ;, e'xamined. • The'
cles, of ^l»^<^-''^^'""f ^ f.nhMic extrrct of urine was slightly preci-
aqtieous solution of a k"f ohc ^^^^^ J.^^ ^^ ^^^J^ /^^ t„ ;
pit.ted by «ol"l'«". ''f £' but the incinerated extract yielded
ever obtained by disuHaton, Q also'prussiate andcarbo-
muriate '>^Pf ^^^ ,S Foce^ds from L decomposition of
nate of potash. This alkau p
the benzoate a»d acetate. ^^^^^^ ^^^^ ^.^^^^^^^ . t„
The salts not ta^en up ny ^f potash, some ia«rtat« and
the solutien cetitained mucj sulpn ^. P^^^.^^^ ^^ ^^ ^^^
carbonate of the satne alkali. _ii redissolublb in water, sa>
These salts being calcined v^e^^^^^^^ - ^^.^^ ^^^^
that they eontaiued no earthy w""*'-
Mr, Ctietreiil on the Excrements of Birds, ^c. ^9
^precipitate lime-water, nor restore the colour of litmus reddened
, by an acid, so that it does uot contain any urate ofpotafeh, as
. stated by Brand6. • «
Hence it appears, that neither uric acid, nor phospliaie of lime
are fbuml in camel's urine ; but that the reddish, oily Substance
which is the odorant and colouring • principle of the urine 6T her-
bivorous animals has been taken for it, as this substance becomes
red by.combiningiiot only with nitric acid, but also with IJe sul-
4)lraric or muriatic. The supposed phosphate of limeis'orily a
.mixture of magnesia and silic«, which retains some alkali ancl
affioial matter.
Horses' arine being filtered some time afterit was emitted, left
>iarbonate4)f Jime, carbonate of magnesia, and a small quantity 0}
«niaal matter. The stale urine yielded on distillation some car.
bonate of ammonia, but less -than from camel's urine. Alkohol
at 40^ took up benzoic acid, acetic ec:d, muriatic acid, potash^
lime, magnesia, ammonia, and probably soda ; it left untouched^
.sulphate of lime, with a small quantity of muriate of potash ; but
,no traces of prhosphate of lime were found.
When hprses' urine is (evmetittd, it does not yield carbonate of
'lime, nor sulphate of potash, as the acetic acid that is produced
decomposes the carbonates of- lime and magnesia, and part of tlie
acetate of lime is also decomposed by the sulphate x>f.potashy by
jwhich sulphate of lime is produced.
The excrements :p(- the eagle and vulture, being digested in al-
icalised water, let'iall, on adding muriatic acid, a crystalline pre-
-dpitate, which wa$ evidently uric acid, as it left a bulky carbo-
naceous residuum when distilled, and yielded prussiate of ammo-
nia and a sublimate similar to that obtained from common uric
acid ; it was^fhanged by 6xymuriatic acid into oxalic acid \ and
it dissolved With effervescence in nitric acid, and became of a fine
.red colour on evaporation, so that it really is uric acid.
<■=
On the oxidizement of Iron* By Mr^ Hassenfiiatz.^^««, de
CMmict voL 67*
Thb very extraordinary experiments of Mr. Darso, respecting
- the oxydizement of iron, requiring an examination, they were re-
peated with the greatest care.
The iron filings employed were previously examined, and found
t9 contain only an 'indeterminable quantity of carburet of iron and
of silica, with some traces of alumine and lime. They were cal-
cined with the greatest care, and cooted under a bell, then weigh-
.fBd, and afterwards ground on a porphyry, and a^ain weighed.
- {[ive grammes of iron-filings werb employed, and the porcelaia
^apBul« weighed 29 34 gr.
g4Q ^u-PaumfT<Ktz on ihe oxudizemiefif qfiroit.
WfiighU Gain. lioitic
Capfiule »nd filings before calcinsktioo, gn 34*34 >■■' "■■ rr — •
after 1| hour's calcination, •, 34-885 Q'54S
■ ■ I ■ when ground, 34*945 — *r-
; ■ - after another 2 bourns caleinatioQi 3 5' 1 0*^ 1 5
when ground, 35*09
after another $ hour's calcination, 36*53 044
when ground, 35*52 r-"-r- O'Oi
after another 4 hour's calcination, 36*3'8 0-86
when ground^ S6.37
after another 6 hour's calcination, 36*42 0*05
- when ground, 36*405 -— — • Q*D15
after another 4 hour's calcination, 36*4X)5
m^
when ground, 36**39 . *r— ^ 0*014^
* after another 3 hour's cajcinfition, 36*39 — r- ?^*r^
* -"When ground, 3^*375 r— 0*0 J 5
' after another 2 hour's calcip^^tion, 36'375 -^ — — r-— .
* ' i ^ whefi ground, 3jS*3(> -r-r* 0*015
" " after another four's calcinatiop, 36*36 — — r^
Of course 100 parts of iron, could not by this operation be
pombined with more than 42*224 of oxygen. The oxide cont^iiir
ed silica, ^lumine, and lime, as the iron : b,ut ijt b^d lost the carr
bone.
As Mr. Darso had stirred his filings while tbey were calcining^
Bnd al^o blown upon them with a bellows ; 3 grdinnnes of the pre-
ceding oxide were calcined afresh seven times 9uccessively» in th^
strongest heat of a muffle furnace, and afterwards triturated. It
Was $tirre<) during these ealcinatio^is with n. glass hook fi^e4 al
the end of a poker, and the air was renewed by means of bj^Jlpw^
At tbe end of the fourth calcination, the oxide centred in tKo
proportion of 45 parts of oxygen, to 100 of iron, b^yoo4 which
proportion it could not be carjried. Guf niveau has, accQi4ing tQ
a private communication from him, been able to combine 44 parts
€rf oxygen with 100 of iron, which, as it is extremely difficult to
procure iron that does not already contain some carbone and oxy-
gen, shows that the above result is very near the truth.
It is therefore probable that some substances got mixed with
Parso'sQ^i^^ during its preparation, and tberefore Ibe difiR"^
respecting the number of oxides of iron remains as before : . a»4
the next enquiry to be made, is the analysis of the alleged whitA
pxide to determine whether there be^ ^s is asserted by PrPUst,
pnly two oxides of iron, one Containing 45 of oxygen with lOO of
iron, and the other only 30^
Observations, — We consider this paper as eaticsly subv^r^iyt
of. Mr. Darso's experiments, ^nd exhibiting their inaccursMSjs in
tne most complete manner. , * • .
( m )
On the coaguldiwn of Albumen by Heat^ and Jcids^ Bjf Mr^
THiKAUp.-^-^im. de Chim. vol. 67.
The coaguUtipQ of jJbunien takea place ip vacpo as well
Its in the atmoa^here ; no gas is disengaged, and no other
nfteradaii. takes piace bnt thai thcr albumen becomes ifisolubla
hi water ; as thai unleu water is formed, which is not probable,
it appears that concrete albunea differs only t'roni the liquid by
its particles being nearer to each other, a^ thus rendered ibk
soluble in water.
Concrete albumen is soluble in very diiuto solution of eaustie
potash^ and thus re-acquires all iis former properties. When tha
aikali is saturated by an acid, the solution is scarcely rendered'
turbid I but if an excess of acid is added, a precipitate is obtained
similar to that formed by the acid and liquid albumen. And
this coi^densation of albumen is also evidently shewn by its
being thrown down in flakes when alkobol is poured into liquid
albumen.
« As albumen is coagulated by heat, it seems as if the action of
water upon it was diminished in proportion to the encreasffd tern-'
perature ; it is however necessary that the albuminous solution
should be in a concentrated state, to undergo a sudden c«aV
gulation, or the excess of water must be previously removed by
the heat.
Acids coagulate albumen, but unl/ess they are very concen**
trated, the coagulation is produced by their combining with it,
and thus rendering it unsoluble. This coagulum is redissolved on
saturating the acid with ^n alkali, even with ammonia. The
least "soluble of these combinations is that formed by nitric acid,
on which account nitric acid will render a solution of albumen,
upon which other acids have no effect, turbid. Almost all the >
xnetalHc solutions are precipitated by albumen. The precipitate is
always com)K>8ed of acid, oxide and albumen, and ii more or
less soluble in an excess of albumen; sometimes it is very
s^oluble in that fluid; hence it is evidently the albumen that
bolds the small quantity of iron contained in the blood in so«
Itttion.
&fsaratians.-^Tht coagulation of albumen by heat has always
b^n a great stumbling block to chemists; and a variety of dis-
cajdant opinions have been> formed upon the subject; the expe«
riinents lately made by Mr. Brandt upon the animal duids, by
means of a galvanic apparatus, of which an abstract was given "
Iti vol. V. p. 456, should kt. compared with those related in
tb« pratent paper*
( «*« i
jsassx
•mmm
Veto preq^ss for' preparing liqijLid Acetate of Ammonia^ or Spirit pf
Minder erus. By Mir, DztTOVcnis^^uinjiales de Chimie, vcl, 67.
Tbs present .processes depend upon the ose of hydrxnneters,
,¥rhicb fr^uently leaei to errors, as do alsof the use of ^reatgents, to
indicate the saturation; ^herefotre<the doafade deconoposition 0/
fl^ts s^ems to oi&r a pjeferable . method.
Acetate of lime dissolved in three times its weight of water,
was taken, and solid cajrbonatte of ammonia was added ; carbooic
acid vas dii-^gaged, ai^d carried with it some carbonate of am-
monia, .y^hkh shewed that the lime took less rarbonic acid to
saturate it tl^tn was contained in the amnu>niacal .carbonate;
required. The .carbonate of lime was separated by ttf^ ftLtre, and
the acetate of ammonia exhibited 6*^ hydf. The nndecomposed
carbonate of ammonia gives a. disagreeable. odour to.tfae .acetate,
and if it is got rid of by heat, an excess of acid occirrs, th^.
iaturation of \9rhichy b;^ ^iquid ammonia, it is difficult to perform
exactly.
Oxalate ^f ammonia being too dear, the tartArtte in;solutioQ
was added to a solution ,of acietate of lime; an excessive
quantity of tartarite of li];ne was thrown down^.sb that it must
1)6 washed with a quantity of water in order to separate the
acetate^ which renders the process inconvenient; althongh it be
exact* ~ '
The mixture of acetate of lime with sulphate of ammonia, of
acetates of barytes and strontian with sulphate, carbonate and
tartarite of ammonia, and of acetalbe of lead with sulphate, car-
bonate and tartarite of ammonia were all tried but found to hi^
inconvenient, and the following was at length adopted, .
Three ounces and a half of acetate of potash we're dissolved •
in one ounce and a half of cold.wat«?r; two ounces of crystallised
sulphate of ammonia were also . dissolved in four ounces of cold
water. The two solutions were mixed, sulphate of potash was
precipitated, and as they had become warm, the mixture was
allowed to cool, and then filtred ; after which the sulphate was
washed with two ounces of cold w^ter, and the liquors being
mixed, eight ounces of saturated acetate of ammonia, shewing
10** by dr* were obtained, of a very slight amber colour, witboul
any disagreeable smell, and which could bekept without altering
The excessively minute quantity of stilphate of potash that may
remalp united with the acetate, can be of no consequenftct .
Mr, Deyeux remarks pn this prj^cejs,, that it is U3(b1€SS to
apply the abstract theory of chemistry to th^ coi^positiOA ^
On tie, Decmpcfkkim tf Suipktt* ft4i
iHCtny me^icaiBents, and that it is frequpotly much better . to
follow implicitly, the formula of the original proposer, unless it
contaiii& som^ absurdity* It may be questioned whether the'
powe^iof tj^is medicine' doe§ not arise from the^suul excess of
alkali that it. cepta^iis.,
To-^btain a medicine always equal in strength, with as little
fleparture as jf>©»sible from the original process^ dry carbonate of
ammonia may :be dissolved ip eigbt ti,m^ its weight, of distilled
water, and dwiilled vinegaXy shewing 6° hydr. may be added
uatil.the effervescence rceases. Although this liquid;wiU not be
exactly, ntutral, it,\iiiOuld be always in the same state of im*
perfect saturatioii.
t»
Obiertations, »^The retnaricH made by Mr^ Deyeux, on the
paper off •Mr. Destondbes, a\t iso just, that it is useless to «ay^
«ny thing 'further, than to allow the merited praise to bis
simple process, as fulfilling th: intention of the original author-
Di the most complete manner.
assssessss^ass^^
A continuation of the experiments upon the Decomposition qfSuhhwr^
By Mr, CuRAUDAU. — Jou7.i. de Phys, to!. 67.
.As the experiments mentioned in. the first essay on tliifr
subject were judged to be incOaclusive, the following new ones
were made. . • . • . . . > . .
Instead of elixiviating the residuum of tbe <;alclned animal
charcoal and sulphate of potash, as in the former experiments j
it was mixed with one fifth of sulphur, and heated. At. first mucl^!
ammoniacal gas was emitted, to whiqh. succeeded hydrogen and{
caiburetted hydrogen. The residuum being elixiviatcd, the ley
was darker than before, which shewed tli^t it contained more
carbone ; it also contained less prussic acid, but on being exposed
to the air for some months^ the. property of forming Prussiaa
blue was gradually increased.
As the residuum did not yield hydrogen before 'the sulphur wa»
added, that gas must. come from tlie sulphur: the carbone found
in the ley must also come from the sabie addition ; and the des-
tructioR of the prufisie radkal 19 fxplanable by the hydrogen of-
thc sulphur combining with the azote, and forming ammonia
which escapes.
A solution of azotised- sulpburet of potash acidulated with
sulphuric acid, yields with a soluti<ii of sulphate of iron at the
maximum of oxygenisement, from one fourth to one third more
Prussian blue than the sulpburet acidulated with sulphuric acid
saturated with nitrous gas; whereas-the contrary should, on the
iU Oti the DUddilky of Atkohol k Tiemom^eri hy agt^
tfdmfeaon hypothesis of tbd disoxyg^fiisem^t of Che liitroiiii go
take pla(;e.
The solutroR of azotised sulphur^ of potash yi^lds^ on being
iitrongly aeidulated with sulphuric acid saturated with nttrooA
ga&, ail abundant precipitate of sulphur,- ^hieh it not the casii
^ith oiher acids. It has been thought that the Oxygen of the
Aitrotts gas combined with the hydrogen which held th« snlphuf
In solution, and thus tbr^w down the sulphur. But on thid
hypothesis, why does not the oxymuriatic at id act in the sam^
teanner ? It is therefore probable, that the solution so for froti^
holding any excess of hydrogen is in fact deprived even of som<$
part of that which constitutes the sulphur, and that the nitrouif'
gas really acts by hydrogenisiDg thr dishydrogenised carburet of
auiphur, the water being decomposed in consequence of the joint
iattractions of the dishydrogenised sulphur for hydrogen, and of
the nitrous gas for oxygen, to which attractioas succeed ih«
attraction of sulphur for oxygen.
M*
Ob$ercatiom,'^xi the last number, p. 199, the remarks of
Vaoquelin and Berthollet, on these experiments may be founds
as they recited them in their confutation of his first paper.
issstA
J^ttniym of the DatoUtt. By Mr. VAUQUELiN.^^irvnr. it Fkys.
vol. 67,
KLApnoTH has already given an Analysis of this stone.
The specimen analysed was white, with a slight milky trans*
]]farency ; it scratched commonjglass ; the fracture was glassy'
and smooth, very like that of quartz. It was easily acted upon'
by acids,, and changed into a transparent gelatinous mass.
The stone was dissolved in muriatic acid, and was found tcr
contain 37*66 jier cent, of silica, 21*67 of boracic acid, 34 of
lime, and S.5 of water, and 1M7 were lost in the operation.
OAie/ra/tW.— This analysis agrees very nearly with that of^
Klaproth, which is mentioned, vol. ii. p. 365, \Krhere a further
account of this new stone may be* found.
-^ -I I. ■ " ■'.' J'-^. ■' ■*»"^*«P*i*— I - u'
1 • On the Diminution of the dilatabiliiy ofAlkohol in Thermometers hu
age. By Mr. Honors Fi»aug£rgues.— Jiotem. delPhy$. vol. 60.
2t. Obteroatiom oH the obace paper. By Mr. Cotte.^— JM.
3'. Additional odservations on the abffoe subject. By Mr* HoKOiiC
Fl AUG SEGUES. — Jourtt. de Phyt. vol. 67*
Hallsy and Muschenbr^eck affirmed; that the atkohol used
On the IMatabiUiy of Alkahol m Thermomeicn ly age. 245
fffU* making therxnojneters lost a' part of its dilatabilityy by age„
Hbut Nollet aod Brisson topported \li^ con^ry opinion on the
iaith of an experience of more than thirty years.
But on examining a spirit ' thermometer xnade in'I734yhy
llr. NoUet, it was foand that it fell down 1^ and a qiiarter
{below 0^ when kept in mdting ice*
Another spirit thermometer, made in 17^3 by Mr. Romien,
.and which is inclosed i« a glass tube, hermetically sealed, fell
r^wn to 2^ and a quarter below O^on being also kept in melting
ice. *
It is intended t(^ preserve these thermometers in order to
.examine whether the <ilkohol in them will suffer a further dlihi-
mutioQ of its dilalability : in the mean time it is evident that
^quicksilver i^ to be preferred )for the construction of these instru*
iOients.
Mr. Cotte observes in the above experiments, that at the
(time mentioned, the 0^ of thermometers was liked by Reaumur
»and Nollet, at the freeing point of water, which Deluc hits
ishewn to be eight tenths of a degree above that of meltliYg ice, so
.that the diminution is in reality very slight, and may be 'ajkChbed
»to some other cause, especially as the latest made tLerniometer,
had the greatest difference. That quicksilver is preferabi^^ to
alkohol is certain^; but this arises from its more equal dilata*
ibility. •
In his seqond paper, Mjr. I^auj^ergucs remarks, that allowing
the first thermometer was made, upon the original princjle Of
^xing the 0» at the freezing point of water, as is very probable,
of course the temperature of melting ice would have been ^ O'^'S
instead of •^— 1***25, so that the alkohol must have lost 12 05 of
its dilatibility, instead of l^'?i>, as stated in the former ]j^ ;er.
This loss of dilatability, is therefore neaily similar to that of
the second thermometer, an^ the difference may arise from their
respective ages, and also from differences existing in the alkohol,
«^ it may well be supposed that liquids formed of common spirit
.of wine mixed with about one fourth part of common water, and
^coloured with an equally uncertain dose of annatto, are not per-
/ectly alike.
OhsevotUkm. There is certainly no occasion to wonder at
j^o complex a liquor as the tinged spirit used to fill thermometeiS
being affected by age; of course the observations of Mr. Flaii-
gergues may be added to those examples that have already
foccarred oi slow and gradual changes in bodieSi taking iMny
(years for their coippletion.
TAo. S^.^TOL. VJ. 2 K
( «*« )
f-r'
N
On tht Meam of detefminipg the Proportion ef Acid ondBase^ vi^k
enters into the Composition qf'Sufphate andjilumine^ and in those af
Sulphate, Nitrate, and Muriate of' Potash, By Mr. Cvraubav.
'^Joum, de Physique^ vol, 67*
The results obtained in the alum manufactory at Vaugirard,
being very different from those commonly stated, occasioned aa
examination of the subject.. Instead of ^1 parts of acid forming
100 of alum, It required 43 or 44, and instead of 10 and a half
of potash, 100 pans of alum required 15 and a half. It was
at first conceived, that the surplus acid and potash entered
into the composition of the insoluble sulphate of alumine utrhick
was sometimes obtained, as no doubts were entertained of tb«
exactness of the statements already given of the proportions of
ingredients in alum,
in pursuing this enquiry,' very regular crystals of sulphate of
alumine were obtained, instead of the lamellar, micaceous masses
Mtherto known, and this pure sulphate was a very excellent re,
agent for determining the quantity of potash in vegetables, either
|>efore or ^fter ^heir incineration.
One hundred grammes of sulphate of potash were dissolved by
Jjcat in 850 gr. pf a solution of sulphate of aiumine, at 34* cent,
iherm. and ^02 gr. of very pure alurp weie obtained by cooling
^he solution. By evaporation, the liquor yielded first 18 gr. and
then 4 gr. more of alum. ^5 gr. of the above solution of sul-
j>hate of alurnine yvere th^n ^dded to it, but scarcely any alum
was separated.
62 gr.. of potash purified by alkohol were saturated by 48 gr.
of sulphuric acid at 66°, and the sylphate mixed with 850 gr.
of the solution of sulphate of alumine, at 34^, and the process
.carried on as before; but only 408 gr, of alum were obtkined, in-
stead of 524, which shewed, that the proporti9n of potash and
acid contained in sulphate of potash, were incorrectly stated at
€2 per cent, of the alkali. The exactness of these experiment^
"were evfdent, from v^ying the quantities of the two sulphates)
and, it was equally evident, that, knowing the. quantity of alum
i;iyen by 100 gr. of sulphate of petash ; and, on the other hand,
.by & giv^n quantity of potash saturated with acid, it was easy to
^calculate an exact statement of the proportion of the ingredients
|a the sulphate.
From the preceding experiments, it appears, that potash ought
gform 4-5th8 ol the weight of sulphate of potash; but as this de*
rminatiMi was opposed by the acid not being capable of losing
/niOjre jUiap 2-3d.s of its iveigbjt ij^ combining with the alkali^ i( tv84
Atr. durHtiau oh the Camposttion •fSidphatey ifC. iXf
cBbiieivedy that the potash itself lost some of its wetgttt wheit '
tombiaed, on account of its not being, any more than the acid^
ift a state of perfect dryness. It is hov7, indeed, agreed, that
potash purified by alkohol contains water ; Berthollet estitnatet
the moisture at 15 per C'eiit. aiid Ilardet, from hid iSxperiments^
finds twice as much.
The interesting expcriraerlt of Mr. Berlholl^t, in Which potasli
was treated with iron filings, is not sufficiently rigorous ; and the
substances that are employed to discover the water contained iii
potash ought not to be oxidizable, but' their action should be
confined to the niere Separation of the water contained in the al-
kali.' The following appears to be the b^t adapted for this pnr^
pose:
^0 grainnies of potash, ^^bi(^h had be^n prepared in the la-
boratory of Mr. VauquSlin, were mixed with l6d grammes o^
very pure siUca, which had been previously heated for two houri
in a forge lire ; the mi^cture was put into a glass tube, weighing
7^ gr. which was placed ia a 6mall cylinder of plate iroii to hin-
der its beidg melted by the inlniediate adtioti of thd fire. It waA
then ejttiosied to a vdry moderate heat for an hodr; i& toon as it
was warm> a copious emission of vapour took place for five or six
minutes, after which nothing was emitted. The tube had lost
A gr. and a half of its Weight. The experiment wad frecjuently
repeated with th<i same result. Hence^ it appearj^, that potasli
purified by alkohol contains ^7*^ per ceht. of water, add, of
course, that stilphate of pdtash contain^ d7*7l per cient. bf pot-^
ftsh, instead of 5% as stated by Bet'gnianf).
It is remarkable, that Vaucjueliii's analysis df th^ different
kinds bf alum, ^hewd, that sulphate of potash is fouhd in them^
in thd same prbpdrtibn as is stated dbc^'^cf ; and, it is tb be re«
gretted, that Vauquelin Shduld have adopted ^ergmatth's statiQ^
ment respecting the ingredients of sulphate of potashi
To ansilyse nitrate of potash, ioo grammes of it were dissolved
by heat in SOO grammes of solution of sulpliate of alumine ai
34^ by dr. STG'gr. 6f alum were obtained by cooliiig ; andl^ as eva-
poration only produced a confused crystallisaiion, 10 gr; of suU
j)huric acid at 66^ were added, as an excess ojf sulphuric acij is
heceisaiy to favout tb& crystallisation of alum, wh^n the liquid
^contains a foi*eign ad^d ; 84 gr. pi alum were imrhediately tfarbWii
clown. Another hundred grammes of the solutibii of ftulphdtiS ftf
aluihinCi were added to discover if any altini still remained ih ilte
liquid, and i2 gr. were obtained, in all 462 gramnies. Which it was
htcessary td piirify by solution 4iidl crystallisation, on aClcount of
the a}um having been formed' in a liquid containing a foreign
acid/ By this ineahs, <^he aluni was reduced tb 4I>^ grammes.
*ry^ Experiment was frequently repeated. With the same rssult,
^d^-MiH IOO gr; t)f nitrate of potash j^roducfe 453 of alum^ it 8]^
\ '
14t OUervaiwm on Spwdle Pkonoite.
pears^ t&at the aitrate contains 49*7^ of potash and 50-24^f
nitric acid*
100 grammeei of dry muriate of potash, treated as in tbe
preceding paragraph, producied 607 gr* of alum, which was re-
duced by refining to 59t ; of course, the muriate contained 65' IJ
of potash, and 34' 83 of acid. This experiment was also repeat-
td several times with tbe same result.
. It appears, therefore, that sulpbate of potash contains 4^7*71
per cent, of potash, and* 42*29 of acid, equivalent in strength to
00 at 66"^ hydr.
^ To constitute 100 parts of alum, there is required 4277 of
sulphuric acid at 66* hydr. 11*01 of potash^ and 10*5 of alu«>
mine, as stated by Vauquelin. i>
Very pure alum contains 19*08 per cetit of sulphate of pot*
ash, 30*92 of sulphate of alamine^ and 50 of water of cpystallisa-
lion.
The crystallised sulphate of aluminemay be used to determine
the quantity of potash contained in' any substance, and its value
in this respect is the greater, as the product to be weighed is
9.0S times as heavy aa the dry potash that may be contained in-
them. .
QbseroationM.'-^The valae of this paper is considerable, as s
ipaetliod was long wanted to ascertain the quantity of potash exist-
mg in vegetable juices and similar subjects* It is a pity- that
Mr* Curaudau Lad not confined himself to the manufacture of
alum, and the things connected With it, and had not, by endea-
vouring to obtain objects beyond bis reach, exposed himself to tbe
rej^ehensionft of his fellow-chemists, as has been the case with
respect to his papers on the decomposition of sulphar, apd the
existence, of carbone in the metalloids formed from tbe alkalies.
«aBaBBBaHBB9MnMaiWBeBaBaasaaBBaBa>99ss^
Observatums on Spndle-TUonagtt^ or Ca/lonite^ and particularly on
that found in the Neighbourhood of MofitpeNier, By Mr. Mak-
cxi Dt SmKEs.— -/otrm. de Fhys, voL 67*
. Tii£ pleonaste was first fonnd in the island of Ceylon, along
tvith tourmalines, and other crystallised substances with which it
■pa» confounded; Delametherie, who first arranged it as a p^u«
iiar species, found it afterwards among the rocks ejected by
Mount Vesuvius ; Lbermina found it among the same rocks, cuid
Louis Cordier has observed it in all the vokauie roc%B of Closter-
slajuck on the banks, of the Rhine. .
praparnaud found pleonaste in the breccias of^the small Wal'
fie hill of Montferrier, where it hofi been recognised in ^ tpfhv^
jnesenibling a breccia. Hitherto these stones have only be^
J
0» Ifodala of tkroafoHfid in CUd'stonf. 9V§
foimd In this breccia ia shapeless and roahded fragments, wbich
wre slightly altered, or at leabt rendered duller than usual in ito
colour. The pleonaste is merely accidentally found in this brec-
cia, and it is also found in the ravines at tliCr bottom of the Jiiil,
ani^ng the substances which have been rolled down it;
Pleonaste is also found in some quantity at Soret, on the left
bank of the Lez, half a league from Montpeliier, on the surface
of a sand composed of rolled quartz and shells. This sand lies fm
beds of sandstone, which are very various in their appearance*
and sometimes covered with shell limestone, containing chiedy
ostrese, balani, and cardia* The beds of sandstone contain n\i-
merous concretions in liimps of vari<3u3 ^izels, all lying in tin^
' same direction, and indicating a mode of formation like thai of
common flints. The pleonaste appears to have been brdiigbt
upon this sand by some accident by means of water.
This stone has al^o been ^und on the vblcantc bill of ValnM*
faargues, on the north of Montpeliier, and in a bed of basaltic
tophus three chiliometer6.(two miles) long, at the bottom of »
bill near Prades, on the north-east of the above city.
From the hardness of pleonaste, it does not seem to be a vol*
canic product, but formed in the humid way, before it was depo-
sited in the beds wh*jre it is now found* It has not yet been
found in the lava of the Vivarais, Auvergne, Etna, Eolia»
Islands, Iceland, and the Isle of France, but only in the cavities of
' certain rocks of Vesuvius, Somma, Closterslauch, and Campania.
Kence, it appears to belong to the primitive rocks, especially
since it is found along with tourmaline in Ceylon. Bui Brong-
piart follows Werner's opinion, and thinks the pleonaste, as well
as the coripdon-telesie, belongs to the secondary trap formation,
which seems, in fact, from the above remarks, to have some
foundation in respect to the former. An exact account of the
repository of corindon-telesie (ruby and sapphire) is, however,
wanting, v^hile corindon-adamanf In, (adamantine spar) is found
in granite rocks, into which it sometimes enters as a component
part, like felspar in common granite ; and therefore, it is pro^^
bable, that corindon-telesie and* addmantin, as also spinelle-
pleonaste, belong exclusively to primitive recks, although further
observations are wanting.
t
iiw— nmiiiiM mil iiiiiii i i i ' ' fi'iiii
'On Nodules of Laxia fmni m Clinkstone, -^Joum* de Fhys. tol. 67*
The rock Sanadoire, in Auvergne, has been described by se-
veral naturalists, and, of late, several nodules of lava have heen
ibupd in masses of clinkstone ; some of these nodules scarcely
adhere to the mass in which they are found, others adhere more^
istrongly, but 6(U1 they are eatkely drifereAt. The sil^ffitCe o£
1^59 tUmahh on tit decimposiiim $fSufyiui^.
those separated by a bammer, is rounded> bat irregular ; it il
smooth, and covered with a light shining coat, which appears Xjti
be a very thin pellicle of clii kstone.
The nodules are of different Jcinds of lava ; the commoneBf va-
riety is of porbns, stoney lava, of a gtay, or blackj^b gray ground
colour, with needles of pyroxene, and flakes of felspar ; some are
i>f black compact lava, which present, vi^hen broken, a multitude
of small needles of amphibile or pyroxene, so that they might be
taken for fragments of an am phobolic rock, (common hornblende)
if some of them did not exhibit unequivDcail marks of the action
of fire.
, A large mass of blueish gfay cHhkstoffe^ fri thif iorreht of
Prent«^arde, which has a le^s polyedric fracture than that of
Sanadoire, contains gray lava intermixed with very small (*fystals.
Lava is also found in the clinkstone of La Vedrine; and pro-
bably in all the clinkst^ii|e rocks of this part of the Mon^ d'Qr.
Chnkstone has always been considered in France as a kind of
tava^ and known either by tbe name of greenish petrosiliceou^
lava, or greenish basalt in priSmS or tabled, oti account of \\M
occurrence along with other volcanic substances. The truth of
this opinion is now proved to a certainty, by the nodules of
lava that it contains, which necessarily shetvs that the rock itself
luis been in a state of fusion.
Observations. — The nodules, which the author, ptdbably Mh
JDelametlierie, supposes to be lava, are probably only a variety of
basalt, which frequently accompanies clinkstone. The vesieulai'
varieties of basalt have been taken for lava by many mineralists
oi reputation.
■'■■■ ■* ■
JUmarks on the Report made by Vauquetin and BerthoUet respecting
the Aiiiho/s two Paper it on the Decompositum of Suipkur. Bg
' F. R. CuRAtJDAU.-^Joiirji. de Vhys^ voL 67.
. If the report, made by the committee had contained any neW*
facts in opposition ta those contained in tbe original paper^ ncf
answer would have been given to it ; but this is not the case, and
the committee merely argue differently from the same facts, tor
^ew that the experiments are of no value.
The experiments which they repeated were not made in a pro-'
per manner, for they added iron-filings to a mixture, in whic£
the iron could have no wfluence in respect to the effect that^as"
desired.
If this addition had not been made, the use of an earthen' Ves<>~
sel, by simplifying the •xperiroent, would have obliged thecom*^
mittee to examiue^why the pnissie radical obtained^ -fk>ra animrf
Ottihe comtruftion and effecU of PneumaHc Tinder Boxes. 251
' charcoal and salphate of potash was indestructible by acids,
nrlieFeas the coiumon prussic ley is decomposed by the weakest
of them.
They allow, that the results of the first experi^ient in the sc-
jcond paper are correctly stated, but they do not draw any infer-
ences from th^ quantity of hydrogen that is eniuted from a mix-
ture in which nothing but the sulphur can be supposed to yield it.
•If they had som^ reasons for keeping silence in respect to this
convincing experiment, they ought at least to have refuted the
consequences that were drawn from it.
. The second experiment, they pass over, as foreign to the ques«
tion; but it serves to explain the phenomena in the third; re*
tpecting which, they affirm, that oxymuriatic acid does not pre«
cipitate .sulphur from the solution, because it convetls the sul-
phur into sulphuric acid. But this is contrary to experience, for
if salphuric acid, saturated with nitrous gas, is poured into the
fiolution, in which, as they pretend, the sulphur is converted into
sulphuric acid, it is immediately thrown down as plentifully as it
would have been before the oxymuriatic acid was added.
The report, therefore, does not overturn the fasts recorded,
Hud the publicity given to it will eventually be favourable to tht
eriginal theory.
The memoir on the decomposition of the alkalies, mentioned ill.
the report, is not that which was meant to be cited; the latter
mras published more than six years before the other.
Observations.'^^Tht reader is referred to pp. 1 91 and 198 of the
last Nuniber for the original paper and report, to which the above -
/observations apply, and also to a preceding paper in the pttaoKt
Number.
wtmeame
On the Comtructian und Effects of Fneumatic Tinder Boxes, Eg
Mr. Le BoviER Desmortiers— .Jotfrn. de Fhys, tot, 67.
It is far more essential, that the syringe should not be leakj
at the extremity than that it should not lose at the piston ; for,
in the latter case, it will still cause the kindling of the agaric tin*
deu A notch of a quarter of a line in breadth was made in the
piston, and the agaric was still kindled ; three 'other notches w^re
^enmade successively in the piston, so that it was divided as if
»rere into four parU^, and still the same effect was produced, al-
-though the air passed so freely, that the piston could be pushed
^own merely by the hand. Pistons, of this kind, made of a solid!
substance, are preferable to others made of a soft substance. If
aaotches, indeed, are cut in leather pistons, they soon grow so large
A^ to let the air pass too freely. ^
tST Of$ fhe emt»fructkm mdeffteU rfFnatauOk Tinder Bowe*,
A single cotcb, equal only to tlie fonr separate notches, in tfcf
mmwoakrence of tfae piston being cut, the agajri^ (^ 091 tafce 6rc^
(OB us>ng the syringe*
The agajric tinder is prepared by bailing it ia water, and then
^b-ying it ; after which it is beat, dipped in a solution of saltpetre^
moifi then again dried for use. If the ley is too strong, the agaric
talbes np too mach sa)t, which retards its kindlii^ The best
sgaric is that which is the driest, the softest^ and the least im-
fffegnated with saltpetre ; the estcess of this last is discoverable
hj the cool taste which it produces npoa the tonjgue, or by the
if»arks which it causes the agarie to throw oat when it is lighted.
The sparks thus yielded by the agaric tinder, have been consis*
4nred by s'vo^e persons, as proofs of tlie pheTM>menon being pror
dnced by electricity ; but they arise frona the saltpetre. Mr. Ve^
Delaonay, however, in pushing up the syringe, wijthoul ^ny agaric^
Iedt a dozen ti«ies,oh6erved sparks twice.
if pistons eould he turned oui of aome elastic substance su£&'
ciciitly compact to be worked in the hithe, it woujd be a great ad«>
Tautage. It has been tried with eaout chooc previously wanned^
i» order to render it still more elastic than it is ; but, on tumt>
ing this substajice, it iblded up under the chisseU so that it was
almost torn to rags ; (however, it acted so well, that a Mroke of
ihree inches was sufficient to kindle the agaric. After a few
strokes, .the eaont chouc swelled so much, that it could not be
tnoved without a considerable force ; a drop of oil .removed this
inconvenience for the moment, but it formed, with the elastic gum^
m kind of ^rarnish, which soon made the piston stick still fastejr
t» 'the tube. These last inconveniences might, perhaps, be
4nrmded, by garnishing the epd of the piston wi(h caout chouc^
and covering that substance over with leather : if this succeedeid^
it might be applied to all kinds of pumps.
-4a'9e9p«et to the cause of the agaric being kindled, it seeme
€3«ident, that electricity is not the cause thereof, for the syrin^
is noft insulated ; ^Uie friction is that of an oily body against me^
€al; ^e atmospheric air is not in an electric state so near the
tiyface4>f the earth, and, i^ it were, only an infinitely small quan«-
lity of electric fluid could be contained in tlie cubic inch, ot
iesft, of air which the syringe holds; nor is it easy to kindle
Agaric by the electric spark. A piece of it was sprinkled over
urith resin, and a large jar was discharged upon it ; the resin
iook fire, bi-t not the agaric. It may, indeed, be said, that the
'olectric spark decomposes the air, and sets .fire to the oxygen, hf
.which means, the tinder is then kindled, but the decomposition of
atmospheric air requires a stronger electric power than can be
supposed to come into action in the syringe.
As metallic syringes do not allow what passes in their internal
part to bii stm, three glass syringes w«;re procured^ by /neaotxif
On the consfrueiitm mdefedi ^Fneumatk Tuider Boxes. ^S%
Hr. Lati!i;^t, the inventor of glass fltttes. The first, 8 in. lonj
And 8 lines in diameter, would not set fire to agaric tinder ; the
second, 9 in. long dnd 6 lines 3-4th8 in diameter, succeeded per-
fectly, but met with an accident ; the third, 8 in. long and 7 Hneft
in diameter, was equally proper for the purpose.
When the syringe was worked, so as to kindle the agaric, A
vivid Bash was seen, which filled: the whole tube, and was the
more vivid as the compression was made ' the more quickly. If
the compression was too slight to kindle the agaric, a slight y^
|K)ur only was observable at the upper part of the tube ; this VaiF
pour I'olled in clouds upon the piston. When it had disappeared,
it re^appeared again, on drawing out the piston, as long as anjr
air was in the' tube. This phenomenon could be repeated severajL
limes successively merely by working the piston with the hand*
The vapour is so slight, and diaphanotis, that it cannot be s^n ik
a strong light, but requires a kind of half day-light.
This vapour seems to he caloric, rendered visible by'the eot^
dei^sation of its molecules by the air, in the same manner as air
bec/omes visible vfhet it passes through liquids ; at least, this ex-
planation receives some confirmation from the following circum*
stances.
Whoa hydrogen, carbonic acid gas, or azote were substituted
for air, the vapour appeared, but the agaric was not kindled ;
as the aypte contained a little nitrous gas, the vapour was denser
than with the others. Oxygen, slightly compressed, produced a
very rare and fugitive vapour ; but when briskly condensed, so aft
to kindle the agaric, the tioder, which usually takes fire only at
one place, was almost entirely burned, although a brass syringe
^as used, which let air escape so fast^ that the agaric would not
kindle in commoa.
The vapour does not proceed from any grease adhering to the
sides and expanded by heat ; for, 1st, It may be observed, oil -the
first stroke oF the piston, before the tube becomes greasy ; 2d, It^
appears only between the piston and the end of the syringe ; 3d^
There is no vapour observable wh^n the piston is leaky, howeyejr
rapid may be the friction; 4th, The vapour is not always mor^
abundant when the piston is 'worked the whole length of the tube,
tban when the stroke is confined to the upper part'of the syringe j
5th, When the air is entirely decomposed, no more vapoiir is pro*-
daced, -until fresh air is adtaittcd-
The colbur of a bit of muslin, tinged with litmus, which wai
|ylaced in the syringe instea'd of the agaric, and fastened to the
bottom by a bit of green wax, was not altered by twenty strokes
of the piston; another bit being put in, and the edges left loose
in Che cavity of the syringe, it was not altered in its colour,
atlthough the edges were burned; lastly, a bit of wet mudin was
•No.fiS; — rbt. vr. 2 l
554 Od making Sirup ^ if c, from Grapet.
not changed in the least, 80 that no acid matter is produced in
this operation.
Sometimes, it happens, that the agaric becomes black, but
does not kindle, and, in this case, a strpng smelling thick vapour
is thrown out, on working the piston ajfresh, the same as though
.the agaric bad been kindled, lliis vapour is entirely differepi
from the other, which appears before the agaiic is affected.
As- the air, as well as the 6ther gases, seem to be decomposed
by a rapid compression, it is probable, that the luminous me-
tedrt seen in storms are not always produced by electricity ; and,
in fact, Saussare's sftmospheric electrometer has, in several ia-
stances, given no signs of electricity daring their appearance. In
particular* a violent high wind occurred in the beginning of
1803, aad lasted for two hours; it threw down about sixty
large trees, belonging to the author ; atrcaks of light were ob-
served twice during this storm, and yet the balls of an electro*
meter remained the whole time in contact.
> OUervations. — Syringes, for the purpose here mentioned, have
been sold for some time in the shops of London. The theory
generally followed, supposes the agaric to be kindled by the cali^
he disengaged in consequence of the sudden compression, the same
as when iron is ignited by briskly hammering of it. It has been
observed, some time ago, that a faint light was observable on dis-
charging a wind*gun in the dark. Both these have some con<-
nection with the author's hypothesis, but the subject is still too
dark to be satisfactorily explained beyond all-contradiction.
BBaBBeBBSaVBHMBBHai
'On making Sirup^ hrimn or tohite Sugar from Grape$j^^By Mrm
FocQUE.— JoKHi. de l^hyu vol. 67.
Miu PARMEKtiER has pubUshcd a method of making sirup
and marmalade from grapes, but the acid of the grape is left in
them, so that ibey require the addition of cane sugar, when
they are used for food, and the birup cannot be kept for any
time without the addition of brandy.
On the other hand, the sirup that is prepared from jQice of
grapes properly saturated, and concentrated to 30"^ Baume's
hydr. keeps for any length of time, and in about two months
three quarters of it is crystallised in spherical crystals, which
are the size ot millet seed, if the vessel has not been moved,
otherwise they are smaller.
If the sirup is evaporated on a naked fire, it acquires a reddish
brown colour, which spoils it for certain purposes ; if a vapour
bath is used, the sirup is' iinch.yelIow« and yields 75 percent,
of cryiX&\% of the saiiM colour^ which xnay be refiaed to a whitt
On making Sirupj t^c.from Orapm. 355
jiolenr. The addition of brandy, or powder of sugar, to hasten
the production of these crystals, had no effect. The \nfhite sugar
made frpm grapes has not the sandy hardness of cane sugar, it is
pulverulent and soft to the touch, and its taste is also less sweet
than that of the sirup and crystals used together.
It is very easy to constroct-a vapour bath by making a bank .
«f rubbish about three feet high, kept in by hurdles supported by.'
.stakes; the top of this rubbish should be covered wrth powdered
charcoal, upon which a tinned copper, or plate tin pan 8- or 10
feet long, 3 feet 8 inches wide, and 6 inches deep, must be set,
the sides being supported by four planks; a flat eteam pipe 1S|
inches wide fronn an adjacent boiler is to be introduced into t,he
pan by one of its ends, and after running round it, to be carried
•ut agaia with a sufficient inclination to let the condensed water -
nin again into ^he hoiler, to which a common still head is to b«
adapted. For small families it is sufficient to place a shallow
yan 3 feet wide upon a comnK)n boiler, at a distance Just sufTi*
cient to let the steam escape under it.
To make about 100 or 125lb. of sirup, 400lb. of juice of
grapes must be procured, 30 or 40 quarts of which are -to be
heated in two parcels, until the hand cannoV be kept in it, and
then poured into the remainder, after which is to be added 40' .
quarts of powdered chalk, or wood ashes, previously sifted, and
washed three times with boiling water. The wood ashes are to
be preferred, as they do not give a bad taste to the sirup, and
as chalk contains particles of clay that fall down very slowly,
it is requisite to filtrate the sirup through a flannel when that
earth is used. The mixture is to be stirred, and then left to
settle for a couple of hours. A spoonful of the clear liquid is
then poured into a cup of milk, which is made to boil ; if the
fiiilk is tunvR), two or three quarts more chalk are to be added,
and after some time the ayrup is again tried with milk. When
the sirup by these additions of chalk will no longer turn milk-
ofk being boiled therewith, it is ready to be evaporated.
The trial of the juice with niiik is better than to use litmus
paper, for when the paper is not altered in colour, there may
•till be left su^cien-t acid in the liquor to curdle milk. The
saturated juice after having been left till the next day to settle, is
to be drawn oflp^ and the sediment drained upon a fine cloth ; after
mrbich a pail of hot water should be poured in three separate
parcels upon the sediment, in order to separate all the sugar
at contains.
If the colour of the sirup is not esteemed of any conseqtience,
i^ may be evaporated in a common boiler, observing to skim
it .vr-ell, until a drop let fall upon a coW pUte, grows bollit leuily
0olid on cooling not to run upim the plate when the lattei is m-
cljned ; or a hydrometer may be used. The sirup mus i theu be
Boured into pots or casJis^ and covered iip^
%5S On Making Sirup f Sfcfrpm Graf€$^
When the colour of the sirup is of coinseqiience, tbe pressed
juice must not tie received in vessels that have been used for
fnaking wine, as the remains of it* would colour the juice, which
must also be evaporated by means of steam.
Sirup evaporated to 30 or 3S^ of tbe hydrometer, Bcquire§ in
a month's time such consistency, that the vessel may be turned
bottom upwards, without the sirup falling out: some sinip
evaporated not quite so far, acquired this consistence in 15 oc
20 day8.«
The juice of th« white grapes, called at Paris, melier, yields
22 per cent, of dry saccharine matter, the red grapes IS, and
the chasselas only 16. In Spain the grapes being richer, yielded
i$ per cent, of sugar.
Four hundred lbs. of saturated juice of the grapes usually
crown about Paris, yielded from 100 to 125lbs. of sirup at 30?
hydr. in which spherical crystals were afterwards formed ; these
crystals when drained on a cloth weighed 751b. but on being
Strongly pressed, their weight was reduced to 60lb. On sub*
Sitting the crystals to the usual method of refining, they wera
rther reduced to 40lb. of good clayed (Lisbon) sugar, from
vhich a loaf weighing l61b. of white sugar was aftexwaidi
obtained.
Observations, '^We have several times had occasion to remarfc
the great efforts made in France to supercede the colonial articles
t)y those of home produce ; and the present exhibits the intended
substitute for our West India sugars. The price uf grapes in
this country renders the process of no use here, but in some of
our southern colonies, the superior richness of grape iuica
above that of the sugar cane may eventually render it more
advantageous to cultivate the vine than canes. The juice of tha
cane yields on an average about one eighth of its weight ol ^
raw sugar;
The paper by Mr. Parmentier, mentioned above, was abstracted
l^y us, in our last number, p. 209.
. The quantity of chalk ordered by Mr. Foeque to be put into
the juice appears to be very great. lu India about three spoon*
fuls of lime are added to fourteen gallons of cane juice. In
i^merica a spoonful of lime is considered sufficient for fifteen
gallons of sugar-maple juice. According to Mr. Dubuc, apple
juice requires about one drachm (gros) of chalk, and the juice
of pears about two drachms per quart. Some error must there*,
fore exist in this part of the original, especially as he orders the
"wood^ashes to be elixiviated before they are used, which, taking
away their alkali^ mu^t render them less useful, and indeed nearly
useless.
Examination of Aloe Socotrina and Hepatka, 257
Pkrmentier orders half an ounce 6f washed woed^ashes,
dialky or whiting to be added to 25 quarts of the juic^ of
grapes in tlie south of France, and twice that weight of Jkaiine
substances to be used in the north, where they do notri -ri per-
fectly, £0 that it should seem as if 4- oz. of chalk would be tiittfi-
cteiit, and then a much less quantity of water will be required for
IJQe purpese of Washing out the saccharine matter from the re-
^duum*
Compar4Uioe ExmruKation of jfhe Soeotrina and hepatica* By Mr^
TROMMSSiORFF. — Ann. dc Chim. vol. 6S.
Th«ii£ are four kinds of aloes ; aloe lucida, which is very
rare ; aloe caballing, which is very inferior and variable in its
qualities ; aloe Socotrina ; and aloe hepatica : the two latter onlj
are worth examinijng.
Four ounces of aloe Socotrina boiled in three lbs. of distilled
water formed a deep yellow transparent solution, but on cooling
a yellow powder separated^ and when quite coid^ a yellowish
brown transparent mass was left, on the liquid part being poured
ofT. This mass weighed on being dried, one ounce ; it was very
brittle, bitter, fusible by a slight heat, and insoluble in water,
hut very soluble in alkohol, or liquid potash* It also burned with
a vivid flame, whence it was evidently resin that had been taken
up by the other substances while hot, but separated from thera
ly cooling.
The watery solution was deep gold colour, perfectly transpa.
rent, h^c«ming brpwa by contact of the air, but nut growing
turbid. It reddened litmus paper ; the alkalies, and alkaline
carbonates destroyed this property, but. produced no other change.
Muria.te of iroo ad maximum changed it black ; nitrate of silver
or lead rendered it slightly turbid, but nitric acid restored th#
transparency. Sulphuric, nitric and muriatic acids precipitated a
little yellow resin from it, not e^^ceeding however two per cent,
gelatine does not produce any. change in it. On being evaporated
in a water .bath^ it l^t a bitter ipass resembling aloes. The
powder of uiis mass was soluble in alkohol either hot or cold^
but not in ether, which it did not even colour in the least ; it
was therefore the sappnaceoujs principfe, called by Hermbstaedt,
seifenstofT, or pfianzenseife, found also in saffron, rhubarb, and^
several other vegetables.
Four ounces of aloe Soootrina were almost cnvnpletely soluble
in l6 02. of alkohol, a« only 12 gr. of woody fibre were left on,
ibe filtre^ The solution was deep yellowish red. It was mixed
with its weight of water, and the alkohol distilled off; the remain*
^& ^^W4 ^^. i^ot U^bicV but oo beiog evapors^d to dryness mid
25 i Description of an Htfgrometer/or Gasei.
redissolved in boiling water, it let fall an ounce of resin on i^ool*
ing, which corroborated the former txperiment with water.
Sixteen ounces of aloe hepatica dissolved in water, left on cool-
ing the solution three ounces of resin* The solution was equalljr
acid as the former, it was rendered black by muriate of iron ad
maximum, and made slightly turbid by nitrate of silver or of
lead. By exlccation it left a mass soluble in water either hot or
cold, without depositing any resin ; the dry mass vfsa also soluble
in alkohol but noi in ether.
The three ounces of resin separated from the solution in water
left, on being treated with alkobol, two ounces of residuum, which*
was divided into three parts. One part was distilled, and it
yielded a fetid oil, ammoniacal liquid, and a bulky charcoal.
Acetic acid had no action on the second, but the thirrf wai
totally soluble in boiling caustie potash ; the solution, was not
rendered turbid by water, while acids separated a spongy brown
mass rather elastic, which yielded an ammoniacal liquor on being
distilled ; hence this residuum was probably coagulated vegetable
albumen. The alkoholic solution left on evaporation a resinous
mass« insoluble in cold' or hot water, soluble in alkohol, ether, or
caustic potash, easily fusible, and very inflammable.
Four ounces of aloe hepatica left four and an half drachms of
albumen on being treated with alkohoL The sohition itself waf
evaporated to dryness ; the residuum was totally soluble in water,
but two drachms and an half of resiD fell down when the water
cooled*
Aloe Socotrina may therefore be .distinguished from the hepar
tica by the former being totally soluble iii alkoloY.
It also appears from the above experinients, that aloe Socotrina
contains 75 per cent, of the bitter saponaceous principle, S5 of
resin, and some traces of gallic acid ; but aloe hepatica contains
81*^5 of soap, 6*25 of resin, 12*5 of albumen, and some traces
of gallic acid.
. The saponaceous principle and the resin appear to be of the
same nature in both kinds of aloe.
ObsercaHon$»'^The examination of aloes has lately occupied
the attention of the most experienced chemists on the continent,
fts may bo seen by the succeeding papers. Messrs. Bouillou-
Lagrange, and Yogel take part with the present author against
Braconnot. ' -
v^ammamafmmmmmmmammmmmmBmmBOBm
Description of an Hygrometer for Gaset^ and oftk$ Manntv tfvsing
it. By itfr.'G VYTON MoB,YEAV.p^^fin. de Chan. wL 6i«
This is nothing but a sjpmU phial of flint glasS| to which «
Contpttrative Examnation of MocSfGamb9gt^ S^c, %5Sl
$topper oF the same is fitted ; the^ whole is then fixed in aa
apparatus made of ii*on, by means of which it may be passed,
completely closed, through the quicksilver in a mercurial pneu-
matic trough, opened at pleasure, and after the enclosed sub-
stance has remained exposed to the action of the gas for any
desired time, it may be stopped again and withdrawn.
When the hygrometric state of a gas is to be examined, the
phial is detiaLched from the iron collar in which it is screwed, and
'Weighed; it is then filled with muriate of lime previously melted
and powdered, and again weighed. It is then introduced into
l3iegas and left for some hours, after which it is withdrawn and
Weighed. In some cases, fresh muriate should be added, until it
no longer acquires any increase of weiglit.
This instrument must not be confounded with Berthollet's ma-
nometer^ described by him: in the Memoires d'Arcueil/
•^^•m^mw
Comparative Examination of AloeSf Gamboge, Eiiphorbium, Myrrh,
Frankincense^ and Gwn Ammoniac. By Mr, Henkt Bracok-
NOT. — Annales de Chimie^ voL 68.
The best aloes is brought in bladders from the island of Soco-
tra, at the entrance of the Red Sea, and is obtained by cutting '
the leaves of aloe perfoliata Socotrina transversely, collecting the
sap that issues from ihem, and drying it in the sun.
The Socoirine aloe' that was examined was yellowish red,^
semi-transparent, and, when broke, there appeared yellow spots
oii a red.groun(i ; it yielded a fine yellow powder, was very bitter,
and bad a smell which some persons did not find to be disagree-
able. It did not become electric by rubbing. A heat of -f 80^
Rjeaum. softened it, so that it was'moredifHcuIt to powder ia sum*
tner than in winter. It melted, puffed up, and took fire on being
pr«seoted to the flame of a candle.
80 grammes {about 3 oz.) of aloes being distilled, yielded 8 gr,
•f water impregnated with an essential oil to which the alces
owed its smell ; 8*7 gr. of almost colourless water, in which 1 gr.
of acetic acid, but no ammonia, was discovered on adding quick-
Itioe ; 5 gr. of heavy red oil soluble in alkohol; a large quantity
«f oily hydrogen and carbonic acid gas ; there remained *iO gr. of
Jbardy very balky and spongy charcoal, whicb retained much hy-
dlrogeii, and did not lose its black colour, brilliancy, nor gi eat
liardness by an obstinate incineration ; the 7'5 gr. that then re-
mained did not contain any potash. It was treated with mu-
riatic acid, from whence ammonia threw down oxide of iron, and ^
fiome little phosphate of lime, and carbonate of potash threw
dowi^^ a few decigrammes of carbonate of lime. By heating nitric
i6o Comparative EsraminaHoh of jf toes, Gamiogef 4^*
acid on this charcoal, a small quantity of tanning matter was oth-
tained.
Pulverised aloes, ground with cold water, forms a solution that
lathers on being agitated. 148 gr. of water at -f 32^ Reaum*
were required to dissolve 4 gr. of aloes, and 6*1 gr. of woody
fibres was left ; the liquor let fall some part of the dissolved mat*
ter on cooling. A sirup-like solution is obtainable by employing
heat, which is spontaneously prtcipitated by cooling, and can even
be crystallised by evaporation. This watery solution very sensi«
bly reddens tincture of litmus ; its fine gold colour is deepened by
the alkalies and lime-water, without any precipitation ; sulphaut
of iron renders it brown, and throws a brown precipitate ; decoc-
tion of galUnuts throws down a yellowish flak} precipitate, and
the supernatant liquor becomes much less bitter and less co-
loured ; subacetate of lead also precipitates it, aiid the liquor be-
comes almost colourless. Nitr ate of copper or of lead, and mu*
riate of tin, produce slight precipitates, which do noi appear to
be chemical combinations, for muriate of soda, and other neutral
salts^, produce the same alterations, so that the precipitatioM
seem to be caused enly by the salt weakening the action of the
fluid.
A quart of the solution of aloes, kept for two months and a
half, in a well-stopped bottle, quite, full, was not altered in its co^
lour; another parcel, in a close vessel, only half full, was turned
very deep red, and was rendered colourless by oxy muriatic acid,
which threw down a flakey precipitate ; a thiid parcel, in a clost
vessel, only one-fourth filled, had formed a quantity of mucous
matter. Both the two last parcels had acquired a sort pf visco-
sity, and the dec6ction of gall-nuts produced a more abundant
precipitate in them, than in a fresh solution of aloes>
Spirit of wine at 38° hydro, speedily and totally tlissolved aloes;
a few fibres only being left. The filtrated solution was red, aad
so deep as to be scarcely transparent ; water threw down a pale
yellow sediment, which turned brown on being dried. The alko-
faolic solution being evaporated, the least movement, or blowing
upon the surface, produces a kind of crystallization, which disap*
pears, but is iramediatly re-produced.
Olive oil, heated on aloes, had no action upon it ; neither had
oil of turpentine, although the oil acquired a pale amber colour.
Solutions of the alkalies dissolve aloes very easily, and mask its
bitterness ; acids throw down from these solttlions precipitate*
which grow dark on being dried.
Volatile alkali forms a de^p red solution of aloes, which, on
being evaporated, formed acicular crystals, in a resin-like* ntass ;
lime and water disengaged ammonia from this substance.
Weak acids have but a slight effect upon aloes. XQ gr. of aloe»
were treated with 80 gr. of nitric acid at 36* bydr. formed a deej^
Coiiiparailve 'Examination ofAtoes^ Gamloge, <$*c; '^ i4i
V^llow solution, which deposited a yellow ftak'ey substlknce, the :
liquor was then evaporated to the consistence of honeys diluted *
tvith water and filtered, about 2*5^ gf. t>f a y^Uo^ substance \ras
left, which was extremely bitter; but had ail agreeable slrbniatic
ddour. It melted like hitre, yielded an aromsitic vapour rather •
bitter; and Idfi miicb charcoal. It afTorded^ by a gentle heat, the
usual vegetable products, and at last detonated with a purple
flame, leaving a very bulky charcoal, being one third of the 8ub^
stance distilled. It requires 0*023 gr. of water to dissolve 0*2
gr. of this substance at -f 10^ Reaum^ The solution had the
colour of £lrterial blbod, it did not crystallize, reddened tincture of
litmus, and effervesced with the alkaline carboUates. 13 gr. of
alkohol at 33° hydr.; dissdlved only 0*5 gr. bf the yellow matter,
and formed a deep red solution. Heated ndineral acids dissolve
the yellow matter, but it sooii separates front thera. Potash
forms with it a deep red salt, which detonates like gunpowder^*
ieiiher by heat» or by cOritadt with live charcoal, leaving slight
traces of charcbal, ahd a strong smell of Prussic acid; The nttrid -
acid frdni whi&nce the aloetic acid had been Separated, being satu^
rated with potash, depc^sited a ^mall quantity of the red detonat*
ing salt ; nitrate of lime then threw down 3'5 gr; of oxalate of
lime ; the supernatant liquor treated with nitrate of lead and suU
phuric acid, yielded about one gramme of malic acid, partly dry;
Aloes is not a resin, but a peculiar principle that may be Call*
•d re^iho-amer (or resino-bitter), which is very abundant among
*|)lants ; it has been taken for a resin, or for oxygenised extracti^
matter. A auquelin has described it in his examination ofquiD-
qiiina ; it is deposited frbm the decoctions of wormwood, centaq.
tea, calcitrapa and bbnedicta succory, dandelion, fumitory, and
bther plants, w^hich kre esteemed febrifuges. Indeed, the febn«
iuge quality of quinqtiina seems to arise from a combination of *
resino-bitter witii tanum, or some analogous substance.
It is singular that aloes ceases to purge when mixed with pow-
Jder of gallnuts.
Gamboge is generally supposed to be extracted by incision from
the bark of cambogia gutta; it is brought *from Siam, China,
^nd Ceylon^ iu cylindHcal lumpt!, and has only been known 'since
the beginning of ibe \6ih century. It swells and takes fire at the
flame Of a candle, it exhales when heated a peculiar smell, a|id
^rows soft, but is decomposed sooner than it is melted. 60
grammes being distilled, yielded a brown water 'containing enipy.
reumatic acetic acid, a little light oil, and much heavy thick
brb>^n oil t 8 gn of light charcoal were left, which produced at
last 0*5 gr. of ashes, from whence 002 gr. of poiash partly
combined with sulphuric acid' were obtained, also 0*04 gr. of
phosphate of limej 0 06 gr. of carbonate of lime, aud 0 3 of quart*
zose sand holding a little charcoal and some oxide of iroB* Tbo
Ko, 25.—VOL. VI. 2 ¥
tQ2 Compta-atke Examinaiion <f AloUy Gamboge^ 6fC.
liquid prodact9,did not 4eem to contain any ammonia on bein|p
titled with iimd and the alkalies.
20 gr. of gamboge treated with hot alkohol» lett on the iiltre ar
grayish mass difficult to dry, and when dry it was brittIe,>aBd weigh-
ed 4igr. lis taste was mawkishyitlet'ton being dissolved in water^
only 0*1 gr. of impurities; the solution reddeiitd litmus, and left
on evaporation, a transparent friable mass like plum-gum. The
alkoholic solution of gamboge was red^ and left on evaporation,:
tS gr. of transparent red resin, tasteless, electric by friction,^
which exhaled a peculiar scent on- being reduced to a brilliant
yellow powder. Water added to- the solution, produces only an-
iiniform yellowish milky liquid;
ijolution of potash rapidly dissolves gamboge, and forms a>
deep red, oiUlike liquid, which by evaporation, crystallises like
the solutions of aloes. The potash is neutralised, and the liquid-
yields a friable mass on drying. It tastes like rank grease ^ith-
a slight acrimony, and dissolves in water without rendering it
turbid; acids coagulate this solution into a firm yellow mass.
Limewater throws down* an orange precipitate, as do also the
earthy salts, and those of the white metals. Sulphate oi iron
is precipitated brown, and nitrate of cepper green.
10 gr. of gamboge treated with 80 of strong nitric acid, until
the matter ivas dissolved and reduced to a syrup, the liquid
yielded, on cooling, a mass of crystals enveloped in a viscous
substance, which, on being washed with water and dried, weighed
0*3 grs. The liquor tiiat distilled over, being saturated witb
ebalk ai|d distilled again, yielded an acidulous liquor, extremely
penetrating, and biiter ; it was changed yellow by alkalies, and
'threw down from sulphate of iron a precipitate entirely soluble
in acids; hence it did not contain any prussic acid; tha
substance left by the nitric soution was ydlowisb, bitter,
partly soluble , in boiling water ; this solution grew turbid
on cooling, and part of the substance could then be sepa*
rated by filtering. It was of a reddish yellow, it lathered, red-
: dened tincture of litmus, became deeper coloured on adding an
alkali, and very slowly precipitated sulphate of iron. It did not
- melt so easily as gamboge, up(m a live coal, it exhaled an aro-^
matic odour, aiidjeft much charcoal. It formed transparent red
solutions with potash or alkohol. It was soluble, without alte->-
' ration, in nitric acid, and water produced a white coagulum with
this solution. 0*4 gr. more of the yellow resin ^were separated
' from the supernatant nitric acid and water used for washing the
\ iirst parcel, as also 1 gr. of acidulous oxalate of potash, and 3 gr.
of bicter matter coo taming iualic acid.
Oxymuriatic acid gas was passed through gamboge suspended
in water, more water was then added and the liquor Altered, and
the sediment washed with boiling water until it no longer red-
dened tiaclur^ of lituiua. A pale yellow tasteless powder was.
<jpmparaHx>e Erammation if Aloe*^ Oamboge, 4*c; 9$^
ieftf %Thich cFjackled between thi* teeth, it was not soluble in boil*
,ing water, nor did it melt easily, nor exhale any t^mell Hntil U
took fire, an^ then it emUled a strong smell ol' muriatic ac^k
Weak acids had no etiect upon it, bat strong ones produced charr
fCoal and muriatic acid* It formed with pat^jsh a substance- of ait
agreeable soapy smell, in the solution of which, nitrate (Jtf silver
forms a precipitate partly soluble iu nitric[ actd. 6 gu of thif
yellow substance yielded Qn distillation into water, a liquid wliicii
fcparated 5*4 gr. of muriate of silver from the nitrate of thaf
metal, and 2*1 gr. of ebarcoal remained ; hence it contain^ ^2:$
per cent. ^ dry muriatic acid, 3^ of charcpal, an^ ^ of ojcygeoi
liydrogen, and carbone.
- Muriatic acid heated with thfe resin of gamboge did not prb*
.tiuce a similar substance, hence it is probable that, the resin i9 dif^
liydrogenised by the oxymuriatic acid gas. It is also probab^
-Uiat when vegetable substances are discoloured by that gas, i%
.enters into combination.
Gamboge is a real gum-resin; it has beeii used as an aJHir
Arthritic, whence its [French] name of gomme gutte ; at present
it is only used as a drastic purge.
' Euphorbium runs naturally from several plants of that geQia$|
the common was supposed to come fi om the euph, officinalis, bil(
in garbling a large quantity, some branches wece found whidft
evidently belonged to the euph. Canariensis* Tbat used was in
branched te^rs^* spongy^ friable, pale yellow^ scmitransparent Hkt
bees wax, aiid so' acrid, that on putting a hit on the tongue, the
inouth was in^mer^iately inflamed, an^ a reaching brought 0||.
it melts easily, and loses l.-20th of its weight; 4 gr. treated with
IQO gr. of. water left 3 gr. of insoluble matter ; the ^Iterod 9oh»-
tion was amber coldur^ and bitter, with a slight acrimony. It
reddened tine tuTve of litmus, oxalate of potash produced in it n
precipitate of oxalate of lime ; the white precipitate from nitrate
of 4ead was soluble in distilled vinegar, as also the yellQw preeijH-
iate from lime water.
20' gr. of euphorbittni treeted with 90 gr. of alkohol at
M^ left 6*4 gr* undissolved. The solution grew turbid in two
days time> and deposited a gelatinous^ white, granubr matteitt
which weighed 4*7 gr» but on befug dried and melted, was r0»
dueed to 3*4 gr. It was ' semitrausparent, might be cut, was
easily softened by handling, and was entirely vpla^sed upon a red«
hot iron, exhaliiig the sm^l of bees*wax. This wax still retainei
some acrimony, but made a- very gopd taper. The residuum that
did not dissolve in the alkoh(!»l, was boiled with watej-, some
hranehes on w|iich the eupborbiuni was moulded were left,
weiring 2^ gr. the watery solution being evaporated, it foriued
a varnish on the vessel, and left 4' 1 gr. of brittle micaceous
Bcalee of maldte of lime, 'i his malate wiss mistaken by some
former cbemisU for gum^ and confounded by Laudet' with the ex-
I
ttfi &omp(traiive Examinafion ef Jl&es, Gamhegc^ ^e«
tractnr* matter. The cle^r alkohoUc 8olution« being evaporat^^i
left 8*3 gr. which left, on being treated with cold alkohol, 0*4 gr^
of wax; the fresh alkobolic solution left on evaporation a resin^
from which w^ter extracted 0*4 gr. of malate of pot^isb. The resin
16 transparent, reddish, f^xccsaively acrid, apd electric by friction \
alkalies do not act upon it, for nitric acid did pot repder turbid
eaustic pptash which had been beat«d upon the resin, but aftef
some time, a few reddish flakes were separate^. It is soluble '\x\
jcold sulphuric acid ; nitric acid softens it, and, t>y heat, a soIu«
tion was obtained which yielded by evaporation, much yellowish
resiti-like matter, also a soluble resinor bitter substance aud foq[if
traces of oxalic acid.
- Euphorb'iunq, therefore, contains 5 .per cent, of watpr, 1$ ®f
^ax, 13*5 of woody substance, 20*5 of malatQ of lii^^e, 2 of maf
late of potash, 37 of resin, and 5 were lost. \% if probable, that
the jtli^e of our European euphorbias (spurge^) is siuaijar to that
of the Indian, which is certainly one of tb^ mQ^t yiple^it dra^tic^
and epipastics, < .
• Myrrh is probably obtained by incision from some plants of
the genus amyris ; the specimen, examined was in transparent red-«>
dish yellow tears, with a slightly acrid afid bitter aromatic taste,
In some of the larger lamps, were white nuclei maiked with
tines, ^ud more or less opake, which burned with much flame,
-vihW^ the transparent tears burned like gum : some pieces are air
most colourless, ^nd /soluble in water, being a peculiar kind of
gum similar to what exists in the m3'rrh. Aiyrrli, therefore, a^t
pears to be a very variable drug.
' 30 gr. of myrrh being distilled, gave 10 gr. pf heavy empyr<i!:r
tnatic broNvn oil, 10 gr. of a red liquid, which turned syrup of vio»
lets green, and yielded ammopia on adding potash, and acetate of
potash mixed witli oil by evaporation, the 7' 25 gr. of charcoal
Htrere lessened in bulk^ compact, and iridescent, and left on ineine«
ration. 1*6 gr. of white ashes, which yielded to water 0*07 gr. of
sulphate of potash, holding a little subcarbonate of potash. Th^
Veniainder of the ashfes were totally soluble in nitric acid, emit-
ting carbonic acid gas with a little sulphuretted hydrogen ; anw
monia did not precipitate the solution, but subcarbonate of potash
ilung down carbonate of lime.
• 50 gr. of myrrh, .distilled with watj?r, yielded a little volatile
■oil ; the remainder of this distillation passed the filtre very slowly,
^nd, on being evaporated left 23 gr. of J:ransparent reddish bitter
• gum, reddening .tincture of litmus^ sind v^liich, on being heated
"^\tYk boiling water, was Xffi\y soluble in part, for it left a gum.
like mass, insoluble in water or even weak acids ; this mass w£^
very bulky, became brittle by drying, and swelled up in boiliiig
water. On distillation, subacetate of ammonia was obtained,
' also oil and charcoal, which burned \f i(b much ease. Weak nitric
9Cid prodoced from it uxsiUc acid mixed with malic acid, aiu) i^
yellow bitter substance that did not detonate. The part that was
taken up ^y the water precipitated oxalate of lime, from oxalate of
potrashy it did not render lime water turbid, nor idecoction of gal1« .
nuts, nor liquid oxymunatic acid. Solution of lead, quicksilver, and
iin threw down very abundant white precipitates from its sola*
t^ion ; 23 gr* of this gam dissolved in water, yielded, by nitrate o£
lead, a reddish semitransparent precipitate, weighing 20*2 gr«
'which was not divided by boiling water, but oo adding sulphuric
acid, part was taken np^^but 5*3^ gr. of sulphate of lead, contain*
4iig 44ofoxide^ was left on the filtre; l6 gr. of the gum was ob«
^med by evaporating the solution, it contained an excess of acid,
but as it did not yield either malic or phosplioric acid by trea^
inent with alkohol, the liipein the gum wa& probably united with
^etic acid, and perhaps by carbonic acid ; for, on adding sul*
l^uric acid, the solution of gum effervesced and let fall sulphate
0i lime. 1 he remaining 7 gi* of gum were retained by the nitric
acid, the subacetate of lead, however, especially if a liule alkali
1)6 addedy precipitated the whole of the gum. The matter left
when the residuum of myrrh distilled with water was filtred,
|>eing dried and treated with alkohol left 6 gr. of gum similar ta
Ihat just described ; the alkohol, on evaporation, yielded 11*6 gr*
p( brown r^sin, with an aromatic bitter taste, easily softened by
Jiandling, melting at 4S° Reaum. not electric by .rubbing. It
•fliffused an aromatic odour when burned, yielded on distillation
jthe same products as resins, and formed with potash a soap,
.^hot»e solution in water passed, but still turbid, through the ^Itar,
33 gr. of niiric acid at 38^ hydr. poured on 53 gr. of the resiji
turned it bl^icl^; on hea|;ing the acid, 1'5 gr.of a pale yellow resia
•rose .to the surface; t]xh mass was bitter; partly soluble in watei^
and formed ^ soap* V^ith potash that dissolved easily in watei:^
■the solution being transparent and red. This yellow resin con*
tainedmuch charcoal, it w^s soluble in nitric acid, but not aU
.tered by it, aind resembled that produced from gamboge. T\m
.pitric liquor that furnished this yellow resin being evaporated to
.dryness, yielded another gramme of the same. Lime wator,
.added to the washings, separates 1-2 gr. of oxalate of limewitb
a little malate; fy^ supernatant liquor contained a yellow bitter
matter.
Myrrh, tjierefore, contains about 28 per cent, of a very fa*
r §ible bitter resin ; and the remainder is a gum that becomes
; partly insoluble ; on boiling its solution in water, it yields am*
. monia by distillation, -as also azofe by nitric acid, and deconopQsea
• the solntioBS of lead, quicksilver, and tin, by uniting with th^
•.pxide.
I . FrankincenUf or Qlibanum^ Js produced from an African tree,
/ff^ich Lamarck supppsea to be nearly related to amyris Qilead*
I
f0$ Cimfon^m ExanA^Hon of Alc$$, Gmnbcge, 9fe^
CKtts* It is yelUrw whit^, dry, brittle, slightly acrid, and are?
Ktttic, in seiu I trans parent masbes of different sizes, covered with 4
white powder prpduced by the friction of the tears against each
•tber. It 18 dilSciiiltly fusible, easily inftammaUe, an^ leaves a
%Khj leash,
't^ gr. tif fratokincense disti^lfd with water,, gave I gr. of light
ve*lauie oil, of the celour and soBell of citrons. Distilled^ per de.
it yielded much bruwn empyreumatic oil* and but little wateiy
lUii^t, which did not emit ammonia on adding quicklime, but af*
ioraed white vapours with nitric acid^ 3*55 gr. of chatcoal re*
mained, which left 0*55 gr. of ashes, containing 005 gr. of pot*
ash partly united with sulphuric, muriatic, and carbonic acidsi
0*06 of phosphate of lime; the remainder was carbonate of lime.'
' 25 gr^ of frankincense being treated with alkokol, 9 gi"* ^^ a
whitish matter were not dissolved^ This mass, treated with boil-
ing water, left 1*3 gr. of a soft grayish gum-like mass, which wa«
indammable, and produced a greenish resin with nitric acid, s<>
80 that it might be resin that had escaped the action of the al^
kohol. The watery solution left, on evaporation, 7*5 gr. of yel-
lowish transparent, mawkish-tasted gum, easily soluble in water,^
inflammable^ leaving a white ash mostly composed of earbonatii
of lime; the solution of this gum did not redden tincture of lit^
mua, It precipitated oxalate of potash, it did not aSect aicetate of
lead, but precipitated abundantly, nitrate and acetate of lead, an4
feitrMe of q«ricksilver ;. the precipitates were white, and entirely
soluble in distilled vinegar;, it also precipitates decoction of gatl^
a»lii, which the gum of myrrh does not. Lime water is not at;
lleied by it« The gum is carbonised by sulphuric acid, bat no,
Sbcetotis vapours are emitted; perhaps, therefore, it is benzoic
acid that saturates the lime in this gum. Treated with nitric
^atid it yields abont one third of saccharolactic or mucous acid,
t€^ether with a small quantity of oxalic and malic acids. Tber'
•Alkohui, with which the frankincense had been originally treated^
-iteing -evaporated, left 14 gr. of resin, so that 2 gr. probably vo-
latile oil^ were lost. The resin was reddish yellow, which cracked
.fts it cooled, was very brittle, tasteless, rendered electric by fric-
tion,^ and resembled losin. It grew soft in boiling water, but re*
^ quired a higher temperature to melt it ; the smell when burning
wah not disagreeable. Boiled to dryness in a solution of caustio
potash, it left a residuum that formed an emulsion with boiling
water. It was soluble m cold sulphuric acid, the solution waa
fed, and yielded a white pi ecjp^tate wilh water ; M it were heatcfq
'lot some time, water separated a black resin, soluble in nitHc
Mid, and changed, by it into a br)>wn, astringent, rather bitter
mass, whose solution m water precipitated gelatine, but n^t suln
ybuie of it on. Resin of frankincense, treated with 8 times as
mach nitric aci<l, was changed into the foriijer resinilerm n^atter^
Comp^rMtive ExamUatian of Aloes, GanAoge, t^e* VSf^
t^t w^^hings did ndt contain any oxalic acid, bat a residuunt^
wiiich being treated again with nitric acid, yielded a bitter mat*
istv, sokble m water acd alkohol, but part of it !$eparated on tl^ft
^ater being cooled^ and which precipitated several nieiallic solu*
tioBs,,$e that it had some analogy Co resino- bitter.
GdMrnammMiac contains seeds which appear co belong to ^
&pecies of ftrola. It fdrms irregular masses, rather transparent
^n the edges, externally yellowish, internally conchoLdal^ shiningi
-white, sometimes marbled ; it has very little smell in the lump^
|>ut is bitter, nauseous, and slightly acrid. It forms a very white
emulftion wiih water. It lo^es 6* per cent, by a gentle heat. 2S
gr. of Hmntooi^ yielded, on distillation, 12 gr. of liquids, mostly
brown ./empyreumatic oil, which exhaled ammonia on adding
time» and 7'5 gr. of charcoal, that left 5'2 gr. of ashes mixed
with daiod, containing 0*15 gr.of phosphate of lime, and 0*3 of
.«f carbonate of lime*
25 gr. of gum ammoniac, treated with alkohol, left 5*8 gr. of
a whiie substance, which, on being heated with water, left only
2*1 gr« of grayish, soft, glutinous substance, insoluble in water oc
alkohol, turning black when dried, burning easier than gum, an4
leaving gray ashes ; nitric acid gives a yellow colour, and pro?
4uces aliitie oxalic acid. The watery solution left, oil evapora-
tion^ 4,-6 gr. -of transparent, reddish yellow gum, slightly bitter,
rather brittle, and drying easier than the other gums, it burn-
ed without any flame^ and left a wl^ite ash soluble with etierves^
'Cence in acids. This gum is totally soluble in water, and. its
•oltttiun scarcely reddens tincture of litmus, it precipitates sub»->
cetate of lead, i)ut not acetate or nitrate of lead, hut sitrate c£
quicksilver is rendered milky. It does not render lime-water tw?
•bid, hence as its ashes contain phosphate of. lime, the phosp^onw
«eems to exist in the gum combined with the other tlenaents that
fcanstitttle it. Oxalate of ammonia throws down oxalate ai
.lime ; but the acid with which this lime was combiaedv is uo^
kuawn, althoQgh Vauqiaelia supposes it is the acetic acid that
.saturates the lime in eum Arabic and gum U'agacanth. It doea
aot alter decoction ofgalUnuts. It yields with nitric add Euuch
mueons acid, aome oxalic acid, and very little malic acid. .
The alkoholic •olutiijn of gum aramoaiac evaporated to 4ry
Bets, left 17*5 gr. of i eddish yellow resin, transparent, brittle,
when eoU, like wax, internally uDdalated and shining, marked by
the nail, and softened in the niouih, or by handling. Ithasoo
.-sensible taste; it has the smell of gum-ammoniac ; x% is not ren-*
4er€d eleatric by fr^tion. It melts, like wax, at 43% by a stroog^r
jieatU swells up, exhales a peculiar smell, and leaves a very-
spongy liglit c<}al. It is soluble even in oold alkali ; tlie solution
is considerably bitter, as is the alkaline splutioa of resin. Sul*
r|ibum«ai4.dMsolve$ thi^a^siay ana water decomposss the Jolu;*
1
I
ioi Comparaiict Examination of Ahes, Gamtdge^ S^ci
fidn ; if heated, hydrogeniscd charcoal is obtained, whicfai nSixf
being washed, is soluble in nitric acid, and yields, on evaporation^
. in astringent matter, which precijntates glue of a brown colour*
Nitric acid; heated on the resin, first ields white vapours, and
then comes a sudden rush of red vapours, a yellow resiniform
•ubstance is produced; ^hicH re.dissolves durii^g the operation.
On evaporation to dryness, a very pure yellow, easily fusible, resi-'
no^bitter is obtained, soluble in alkalies, in alkobo!, and in boiling-
water» from which latter sbme part is separated when it is cooled.
It is also partly soluble \tt a large quantity of cold water< All
Its solutions are 6f a vi:ry beautiful yellow,' which stains the
bands, and are easily fixed upon wool and silk, so as to produce
most superb dyes, not alterable by o:tymuriatic acid or even \ht
dilute alkah^s ; and, considering the small quahtity that is re^
quhed of this matter^ they are valua'ble even in an economical
\iew. When mixed with gum, it yields a purer and more solid
yellow than gamboge.
Gum.3nimouia6, therefore, contains 18*4 percent, of gum; 7^
df resin, 4*4 of glutiniform niiatter, 6 of wst6/,^^and 1*2 was lostr
it dofes not contain any extractive matter.
Swartz observed a mixture of ifltiate of quirksiK'^r, and- gum
Arabic yielded a precipitate, which Jucks attributed to gallit
acid contained in the gum, and Van Mons to the decona position
of the nitric acid and of the metallic oxkie; but it is really a
coml/imition of the gum with the oxide. . Suijfacetate of lead also
precipitates both gum Arabic ahd gum tragacantb ; the precipi*
Kates resemble cheese, and leave nletallic lead on being barned. •
The resins have not yet been caret uUy examined, and mviiy of
their properties are falsely stated. Rosin, adiled to a Cold dilute
solution of potash, was perfectly dissolved, the solution was
soapy, thick, and drawing into threads like white of egg ; ihe
most dilute acids produce in it abundant white - precipitates ;
alkalies, and even neutral salts do the same, by abstracting
the vfaier from it. ■ A large quantity of common waur also-
'd»conipc8es it; the precipitate is only partly soluble in alkohol;
the insoluble portion contains resin combined with lime. Mn-
'riate or lime turns the solution ot this soap into a whitish soap,
more or less thick, formed also of rosin and lim^. The metallic
salts also decompose- this soap,« and some of the precipitates
might be used in painting. .
' 50 gr. of rosin, treated with potash, yielded, on evaporation,
69 gr. of brown soap, dry when cold, rather- bit 'er, and perfectly
similiir to Starjtey's soap, which might be used in domestic aft--
l^irs, us it lathers very well, and washes clean, but it leaves 4n
the linen a slight smell of rosin which goes oif in the oj^enair.- •
Volatile alkali^ even when dilate; easily, dissolves rosin ^^tUs
Mr. ISerari on Muriate of l^fu i6$
)MiinlblDa4ion, being diluted with water acquires in time thetbick->
pess of starch.
Obser^ativM.-^GreKt praise is due to Mr. Braconnot, for his
numerous experiments on the gum-^resins, whose nature was not
f»roperly understood before his investigation of them, especially
as the subject did not alfow the hope of any brilliant disco*
« veries being made, and thereihre the labour must have been un*
^ertdsen through pure lov€ of the science.
' The solution of resin, in alkalies, has been already known lA
this country, by the papers of Hatchett, which have been printtd
in the Philosophical Transactions. '
' It appears, from these experiments, that the violent caustic^
euphorbium, has been erroneously considered as belonging te
this class of bodies, since, instead of consisting of resin and gum,
ms is tb« case of gamboge, myrrh, and frankincense, it consists of
jissin,^ wax, and the malates of lime and potash, exclusive of some
woody'fibres ; gum ammoniac also contains a kind of gluten, id
additioa to resin and gum. Aloes, that is to say, the Socotrine
species, is considered as a homogeneous substance, which Mr*
Braconnot calls resino-bitter matter ; but this part of his papeC
Is disputed by Lagrange and Vogel, as will be seen in our next.
• The excellent yellow dye, from gum guaiacum, so highly
praised by the author, is worthy of the attention of artists in the
iyifing business, as that colour is usually very fugacious.
Mr. Braconnot has extended his researches on vegetables, and
another paper on vegetable acids has reached this country, an
abstract of Vbich will be given hereafter.
mm
€S
Qfi Muriate of Tin* By Mr» £. Berard.— ^iui/e« de Chimie^
vol. 68.
The usual method of making muriate, of tin, or scarlet compo*
»tlon;which is of so great use in dyeing, is by pouring four parts of
common muriatic acid (spirit of salt) upon one of tin, and keeping
the vessel upon a warm sand bath. The operation goes on very
slow, hydrogen rendered offensive in its smell, from its containing
some of the metal, is emitted, a large portion of the acid evapo-
rates, so that fresh must be added fjrom time to time, and the heat
kept up fdr some days. In' the cold, th<; solution takes a long
time ; two months are not sufficient : Bay en and Charlard em«
ployed six months to complete it.
' Chaptal placed the tin in the water, in which he condensed
%ke* vapours of muriatic acid during the process of its preparation ;
the heat that was disengaged by the absorption^ aided the solu*
NO. 25.-^.VOL. VI. 2 N . .
170 Mr. Berari on Muritfte 4>f ibk^ * *
lion, bat only one fourth of ttn is diB9olved) tkod the MJlatioA Up^
be finished in some other manner.
Tin may also be dissolved, by placing it in a divided state in i(
receiver, into which the vapours of muriate of soda, 4eeoiapaeed
1^ sulphuric acid, diluted to 4Q° iydr, are distilled.
. Oxyiquriatic acid gas introduced into a mixture of tin aa4
common muriatic acid, hastens the solution very much ; and thus
iMi acid at ^0^ hydr. will dissolve one third its weight of tin.
Mixtures of muriatic acid, with from one sixth to one tenth q|
citric acid, act on tin so violently as to throw part of it ot^t of the.
vessel^ and produce great heat. One part of aquafortis at Z5\
Beaume's hydr., and 12 6f muriatic acid at 20^ dissolves one third
its weight of tin in a short time, and the solution exhibits 45t
hydr.
The alternate action of muriatic auction and atntospheric air
yas tried, by pouring muriatic acid at 20*^ hydr« upon granulee
of tin, and after somejbours had [elapsed, the acid was pour«d off;
the granules, then became black, absorbed oxygen from the air»
so that a t^per was extinguished by dipping it intp the vessel^'
and became very hot. When the vessel began to cool, the acid[
viQ& poured on the metal again, and this repeated from time to
time* The first time the acid was f)Oured off, it exhibited 25®
hydr. ; the -second 35 q ; in two days it attained to 45^» It even
attained this point in one day, and might be got up to 50^ by
using a row of basins, so that while the air was acting upon somgt,
of them, the acid was acting upon others.
Muriatic solution of tin absorbs oxygen very rapidly ; ' when H
has absorbed this gas, it will take up a fresh quantity of tin. It
also absorbs oxymuriatic gas. Pelktier proposed the use of this
impregnated muriate for dyeing, but the dyers will Aot use iIl
When much oxymuriatic acid gas has been absorbed, the solution
will dissolve a fresh parcel of tin, which changes its state, and
renders it caj)able of absorbing oxygen.
Muriate of tin at 45 S crystallises by evapoi-atiori, especially
ijf fresh made, or if it has absorbed much oxygen. The mother
water, even after several crystallisations, is still very dense^
particularly if it was evaporated before it was exposed to the air«
^ It sometimes is fuming, and will yield crystals again On addin^^
water.
A bottle which contained 1 4 parts of water, held 2S of mi^cr,
water of the first crystallisation, and 31 parts of that after. several
crystallisations. The mother waters will absorb oxygen fiofn
the air and yield crystals afresh ; if they are exposed in a thia
stratum to the air, the muriate crystallises in very thin ui<l'
light leaves* They absorb oxymuriatic acid gas with coosidal^
|;ble heat, and whei^cuoled form a mass of silky crystals.
Jliuriate of tin may be puri&d. by redissolutioii in .water an4
Mk Moikrat en Acetic Acid. itfi,
^Hfftifl^ation, The crystals ate very soluUe in ^old waler, and
' ^diminished the temperature 9^ Reaum. Tirhen the substancea
Vete originally at 5% but water did not produce any c6ld oa being
naixed vrith the mother water.
As the mother water began to fume when concentrated, it ^as
^iatilled ; weak muriatic acid canie over Srsl, and then a white
tiiass or butter of till wai sublimed. I)ry dxy diuriatic gas passed
ithrough titeniother water, made it fume, and yi^ld crystals oh
^bt addition of water ; but the Ainiing liquor of Libavius ekhalea
thicker and more abundant vap<)urs, and is whiter and denser.
It Appeto tlierefore that the various muriates of tin always
)Dontain an excess of acid, and- are susceptible of infinite variety^
lieace it is ilo wonder that it produces such unciertaib r^^Ults ia
idyeing. The white crystals, wiell draiiied, seem the most ton*
ttant, ttkMl daght i6 be the ohly soibt.used in that art^ being mixed
"With more or less nitric acid, according to the shade that is de*
•%ired to be obtained.
Several difficultiesy lio^ever, have occurred in attempung to
prepare these crystal^ upon a large scale, for the trade ; the
toanner in which they were overborne, will be explained ia a fu-
iwre e^say;
Obietteklons.'^Tht importance of tiii in dyeing scarlet, aiid the
tlifficttlties attending ife being properly prepared for that purpose,
are so great, that every step towards the knowledge of the salts
bf tin, must be esteemed of great consequence in the art of dyeing*
The experiments of Mr. Beirard are therefore valuable, particular*
ly his mode of accelerating the action of muriatic acid upon the
tnetal, by pouring it off, and exposing the tin to the codtact of
ihe air, as this method niight be applied with advantage to 'some
bther alow diesolutions, silch as *that of copper in vinegari for tha
tnanufactare of crystals of Verdigrease,
'Observaiian$ on- jfcetic Acid, . % Mr. J. B. MoVt&AAT.— i^im. if»
bhimicy tW. 66.
♦ •
T^B density 6i acetic acid is not the measure of its strength^
for two specimens of the acid, whose specific gravities were boti^
J "069 at 12'^5 Reaum. contained different quantities Of r^l acid'.
The first was the strongest acetic acid that could be obtaihed^
'it C6nXaitaed ^*I25 pet* cent; of acid, and 12'S75 of tiratef ; 100
ptttU of it saturated 250 of crystallised subcarbonate of soda; it
^Ma withotit any empyreuma,* crystallized between 10 and 11^
Reaum.,' and melted with diflkalty at 1 S"". It distilled very f^s^
even widiout boiling.
The aecond was formed from the first^ by adding a quantity of
i27$ ObsercatioM im Acetic Add.
.water by cakulation. It contained 41*275 p«r cent pi acid, an^
,:i»87S5 of water. 100 parts of it saturated 1 1 8 of crystallised
•BuVcarbonate of soda. It did not crystallise, when cookd several
degrees below the freezing point.'
It had been previously remarkedy that the above strong acid,
exhibited only 9^ hydr., whereas another acid at il^'l bydr, was
BQt crystallisable.even at 49 Reaum., and saturated only 1B6:j25
ipf subcarbonate of soda, it was therefore conceived, that the acid
Itself is more dilatable than water, and that a term existed, C43|g»
nisabie by the hydrometer, at which this superior dilatability
;Wovild exert itself, so that the strength of the acid would be exhw
•blted by the inve^ $e. progress of the hydroaietic indications.
Water therefore. was gradually added to 110 gr. of ibe strong
acid above described, and its specific gravity .was carefully* ob^
.served at each successive step^ as sQon as the acid had- cooled t#
il^'S Reauniurv
Water added lo. gr, spec. grav. 1*0742 or 15f -6 hydF.
ia-5 . V0J7 11-
., . 10- i-ozpi 11-S_
. The acid had now attained its densest state, and the additioB
of water began to lower its specific gravity, at which tioiQ it eeft^
tained 67*25614 per cent, of acid^ and 32*74386 ol^ water,
t JO-5 10763 10*9
12* • ^ 10742 10*6
11*5 1072a - 10-4
Si- 1*0658 9-4
11- 3 0637 9*1
.. 37* 1-063 9*
Each addition of water raised the temperature of Uje^mixture.
The^addilion of 29*54 grammes of water to 100 of the strong
acetic acict, raised the temperature from 12*^5 Reaumf to 13°'5 ;
a fresh addition of 72*46 of water, carried it up to 15.-5, ^
0^«!rt«fw)«<.ii-These experiments are <yntrary to the received
opinions of the gradual diminution of specific, gravity by the ad*
dition of water to acids. Berthollet, in a note, says he Bas re*
peated some of these experiments, and that the resdlts have been
but slightly different from those of Mr. Mollerat^ who ift alfeady
Vnown as a manufacturer of charcoal and other producits^ as may
De seen by an abstract in the present volume of thevBubrospecty
f. 100. . ..
i It. id not s^id whether the acetic acid, whose densities wer^
examined, was jprepared from, vinegar or wood; we. suppose it
was made from the latter, as Mr. MoUerat manufacj^rea. whttl^
was formerly called the pyrolignic acid under tbattnam^*
/
C •«?» i
jsm
jleport made by a Co)nmUee bf the InstitufCf on Mr. Carduddu*s tdst
Memoir. By Mr, Dbyjbux,— -j^n». de Chim. vol. 6§«
Ik two papers presented to the Institute, Mr. Curaudau has
given a vefy positive opinion on the possibility of deeotnpo^ing
soda, potash, phosphorus, sulphur, atid iron ; aud has mentioned
'Vtevtnd exj^eriflEieiitSy from whtnce he draws a conclusion, 'that
chemists may not cmly decompose . iron and sulphur, but' it was
iJso in their power to proditce them from their elements; '
The committee however soon fomid that the author hbd been
imposed upon by some appearanaes in bis" experiments ; but a^
Mr. Curaudlfcu was still unconvinced of his error, he was invited
pt bfi present at the repetition of the experiments which he con.
ceived to be.o^' the greatest consequence, to produce, in fact, phos-
phoniis^ ii:on, and limei from sulphur, potash, and charcoal made
jOrom horni .
Tboreiepieriraent did hot succeed, Mrhich he attributed to the
lurpacjB in. the Medical School not being so powerful as his own.
The next day Uierefare the eomoiittee met in his laboratory, and
th^ experioient made vtrith the .materials provided by the institute,
t{fl#:e^uaUy unsucceesltil ; but .on 'trying it with the saiOfe mate,
rials which Mr. Curaudau had used in his experiments, much
fbUBphofeteevt gas wad emitted, phosphorus combinedwith about
one half of sulphur was colleoted, and- the residuum contained
lime.andi^^io, as. Jbe had affirmed. ■ , ^
On examining the animal coaly however, It was foundT to con.
;^in.40 pet cefit.' of phosphate of lime,, mixed with a little phos-
phate of iron, 1 and even more of sand, and 0*69 of carbonate of
iime;. It wa^theu discovered that the coal had in fact heen made
^om raspings of horn, ivory, and other substances, thataJabour*
er had been empUyed to convert! these into toal, and that it had
l»een trittiuratedlipon a marble slab.
Mr. Curaddaa was therefore convinced of his error^ and it is io
be boped that he will no longer, be temf)ted to publish any moi^
4i|K>n these di^cult points, which be bdieved himself td^^'hive
4rea(ted mth auceess^ and in alL cases he is entreated to bestow
more litCeAtioQ in the reseaii:hes he ^ wishes l;o submit to the ta^
ititute. . f '' •*
«i»<
, Ob$eroQik»(U*^T\aB vety severe check given to Mr. Curaudaiii
^U, we hope, render him more cautious in future; there- WtM
c^rtaidy no precision in his experiments, but the deductions^
wei(e dnemn from analogy, and exhibited a picture of chemical
rASearebes as they wera^onducted before Cramer, Margraff, a«f|;
'it'i On preparing liquH Sugar from Applet or Peari.
the other German authors had introduced the same minute att</D«
lion to the freight of the products, and their agreement witfi
that of the original materials, as was formerly thought to be he*
cessary only, in assaying for the value of gold.
cggatt—eeBBqB ii ■ ■ BSSSmBBBsmsaamsmmmmeamBdmaieeiaaBmi
On the Pjr^aration of liquid Sugatfrgm Appkif or Peari^ J5y. Mr*
DuBUC.-^-<f««..<fe Chim.td, 68.
Si^v&i^iiL establishnieRts have been tncitde m the sonth ol
France, for making fiugar from grapes, it is therefore desired td
communicate the same^adranUige to the North of France, al
apples and pears will prbduce sugar, v/hese ta^e is equsdiy agree-
able as thfit of gr&pesj and cqiially cheap.
Eight iiuarts of the full ripe juics of apples called ortrnge^-vrnt
boiled for a quarter- of an hour, and 40 grammes of powdered
chaik added to it, and ibe bailing oontinued for lO ttntiutes longer.
The liquor was , then clajriiied by' the whites* of S «ggs, and the
liquor was strained twice through flannel, and afterwards reduced
by boiling, to one half of its former bulk, and the opertftion finish-
ed by a islow heat until a thick pellicle rose on the surface, and s
quart of the syrup weighed ISt lb. 10 o<. By this means 3lb. of
liquid sugar was obtained, very agreeable in taste and smelly
which ^sweetened water very well^ aad eVett milk witbdat tiifi*
ling of it. i •
5 qearts- 6f ttie jjiibe of applto called dous leoaq^ yielded
by the same process, I21b. 12oz. of liquid sugar;
8 quarts of the juice of the. sour apples^ tailed Hmit m^tleif
yielded 21b. lOoz. of good sujgar.
8 quarts of the juice of the watery lipples' eallifd Grr^M-^^^ yi^^
cd dlb. and a Mf-
25 chiliogr, or 50lb. of the Ahove 4 apples yielded nearly 4^
lb. of juice; which took 3oz; of 'Cfaalk, and the white of 6 ^ggsf
and produced more than 61b. of excellent liquid siigar.
Ill order to do without whitti of eggs, 901b. of the jaicef 6f the
above apples were saturated with li drachms o^ chalk, andre^
peatedly strained through flannel, but it wae still thick, and dte&
amaable to the taste. 13 drachms 6f charcoal pdwder w^retbeii
l^ojed,' and the .whole boiled for about 10 minutses, and thai
aj^isaiiied twice through a flahnel ; it was then 'cletfr^ but higfaef
€olo^red than usual ; but it produced very good sugar*
6 quarts of apple juice, were treated with 7 drachms of chalky
^nd tm* of baiters' sixxali ctml, pxeviowiyi^AFcbsSied- limit it no Ibn^
pit coloured the water.
1^ A|aar|s^ of apple JAiice of several di^erent kinds, undin-difl^tlit
fU^ges-of ripenessj of which one third was dtnll soilr, *were S8tu£
|»|ed with 12 draehnid of chdk^ and clarified ^ith tk^^wbit^'df
»
' On preparing Kf^id Sugar from J]^pHa or Pears. 39^ -^
6 <Qg£^? some inalate of lime was deposited in small crystals U^ ^
yf^rSi iht end^and separated by passing the syrup very; hot ,
f,})rough . the' fl^ppel j very near 2ib. and a balf of sugio' wer^ •
pbtained.
Iplb. of bruised apples, similar to the last, were left to mace^
laie for 24 hours, and 4 quar^ of the juice were treated ^jkh 4
drachms of chalk and the white of an egg ; it yielded lib. 602,
of liquid sugar, so that the maceration had oeen of senrice. '
24lb. of pears, called pilk^Cy yielded 9 quarts of juice, which,
required IS drachms of chalk, aiui the white of $ eggs, and yield-
ed about 24oz. of sugar, which was less agreeable to th^ I49t9'<
than that of nf|e apples,
6 quarts of juice f^pom one part of ^the above pears^ and fwo of
ripe apples, orange and girard^ treated with % draohhis of chalk,
and the w^iites of 2 eggs, yielded 2&>z. pf very fine tasted ^ugar,
f uperior to the preceding.
6 qiiarts of juice of an equal quantity of apples and pears treated
with 10 drachms of chalk, and loz. of prepared chaixroal, depo*
^ited some nlalate of lime, and yielded a sugar rather darker than
%he preceding, but very well tasted.
Cadet de Vaux says that apple juice does not curdle milk, and
tbat a small quantity of chalk added to it, destroys some part of
the taccharitie principle ; but S quarts of juice from ripe apples,-
called 0raff|r^, which was evidently acid, as it cuidled milk, and
reddened infusion of turnsol and that of violet, was treated with 4
drachms of chalk, and the white of an egg; it yielded !2^9z^of
syrop, between 32 and 53^ bydr. which did not curdle milk/
Another S quarts of the same juice, evaporated to three fourths
of its volume, and strained, yielded 23oz. of clear syrup, which
curdled milk, was browner than- that of the neutralised jniee/
aod approached towards treacle in smell and taste. Perhaps*
the apple called Jean^hure^ used by Mr. Cadet, possesses
the valuable properties of furnishing good sugar by mere evapo«
ration. . .
- It is necessary to observe, that unless the fire is slackened
towards the end, the syrup grows brown^ and acquires the tast^
and smell of btartit sugar. ^ -
' A cwt of^ apples yield about S4lb-. of }uice, which pt<Mint&
nearly 12U>. of liquid sugar; supposing, therefore, the avera^ge^
price of apples to be 1 fr. 20 cent. (Is.) the cwt. and the charges
a^nount to 40 cent. (4d.) good sugar may be prepared for 3 or 4^
sibls (%d.) per lb. The only extra apparatus necessary is a cou«'
pje of copper evaporating pans.
.^VMMM. ■■■•■■■■§
" 4Jkgervaiiotn$.*^We- are here positively informed, tbat tntftufac*
Tories of grape sugar are established in the saulhern parts i^f^
jRroBce; which shews that at the present prices the manufactare*
QfS ' Analyris of three Kinds of Pyrites'.
i^W answer, and we apprehend that it wBl prove a fbrpiidable
rival to the caue sugar, even when the seas are opened. As to
apple aii^ pear sugar^ or rather white treacle, the prospect is not
so promising*
iSBsoisam&mssssssssssssissssssssssgssesammmmmammL
Analyu$ of three kinds of Pyrites, By Mn BvcHOLz.-t<
Ann, de Chun, vol, 68.
. The analyses hitherto published of pyrites with a maximiini oi
sulphur,, are as folbws :
, Proust, * f 4
Hatchett, • •
Gui^iive^u, ,,
Iron.
Sulphur.
4»736
. 52-64
5a-24
. 46-76
52-76
. 47-2a'
52-76
• 46-6
hS'69
. 46ai
47-93
. 52-07
.47-36
. 52-64
. Bucholz and Gehlen, artificial,
Che- usual process is to treat the pyrites with dilute nitric
acid, but this requires a long time, and much acid ; the following
method was therefore adopted: 100 grains of the pyrites were
reduced to powder, and mixed up with half an ounce of
water in a high vessel l^olding a pint, knd concentrated nitric*
9cid, prepared according to. Suersen's method, was dropped upon.
U* . The action of the acid was very violent^ but the pyrites
wHs completely oxidised in less than half an hour, with the ex*
l^noe of about 1 1 drachms of the acid.
: 100 gr. of greyish yellow pyrites, of a euUc ibrm, which
3^ielded a blackish grey powder, being treated in this mannar left<
4 gr..Qfj,siIUacovjered with^oxide of iron. The solution wasr
4iluted,with water, and precipitated by muriatei of barytes; it
yielded 355 gr. and a half of sulphate of barytes ; now as this
salt contains, according to \Yithering, Rose, and the author'3 own
experiments^ 35*2* per cent, of sulphuric acid, and 67*5 of
barytes ; and on the other hand, the analysis made by Richter,
Klaprotb, and the author shew that sulphuric acid contains oa
an average 42*5 per cent, of sulphur, it will follow that this
pyrites contained very nearly 5i*15 per cent, of sulphur.
100 gr. of cubical pyrites, with concave surfaces, and tlie
edges slightly truncated, left 4 gr, and a half of insoluble mattisr
aod oxide of iron ; the sulphate of barytes weighed 358 gr. $a
that the pyrites contained 51-77 ptr cent of sulphur.
1 00 gr. of radiated pyrites left only 2 gr. of insoluble matter,
and the sulphate of bar}^tes weighed 352 gr. so -that the pyrites
contained .49*61 per cent of sulphur.
The average of these aQ^lyses is, 51 pei ceut..pf ^plph^rajid 49
Analysis of British and Foreign Salif ^c. i7t
«f iron^ being nearly the same as was given by Hatchett and
Gueniveau. Proust and the author had used artificial sulphur«t,
which always contains some sulphurct with excess of sulphur.
It is evident that the pyrites that have been examined by va-,
rious. chemists, and in different countries, all belong to the same
fpecies.
Ssssmimm
On a Powder sold as Ipecacuanha. By Mr. Hehri. — dim^.d^
Chim. vL 68.
EoR the last three months the tirug.brokers have hawked about
Paris, * a powder which they sold as powder of ipecacuanhai
taken out of an English prize. On examining this powder,
the presence of emetic tartar was easily discovered by mixing
it up ^vith a little cold water, and adding some hydro-sulphu-
iu.:„.i^ted water, which'immediately produced an orange colour ; 20.
grammes of the powder being calcined, yielded 0*85 gr, of gray/
oxide of antimony. It wai^ evidently a mixture of emetic tartar^
with some vegetable substance of no sensible qualities .
It is therefore liecessary to be very cautious of purchasing
medical articles from drug-brokers.
The general board of civil hospitals at Paris, prepare under
their own inspection, the medicines they distribute to the
]iospitals.N
Obsercaiions »^^Thert is reason to apprehend that most of the
|Hilverised drugs, and pharmaceutic preparations sold in this
country, especially for exportation, are like the above powder,'
meVe suceedanea, and made up of a few cheap and powerful me*,
diciues.
nMaHHHMMHaHHHHMIBHBBBHVeaBBMnHBBBHBaHMHBia
Analysis •/ British and Foreign Salty with a view to their fitness fyt-
Economical purposes. - By Dr. William Hsnrt .—-PAi/. Trans.
1809.
A DECIDED preference has been given to foreign salt prepared
in warm climates by the spontaneous evaporation of sea water, as
8i preserver of animal food, and great quantities of it are imported
into Great Britain; it was therefbre of importance to determine
^whether this preference was well founded. And if British manu-
factured salt was really inferior to foreign salt?* to tiscertain, as
the basis of all attempts towards its improyement| in what this
inferiority precisely consists. .
JJo. 2.— VOL. VI. L 2
SrS Analysis ^Britiak and Foreign Salty ifd
Cheshire stefoed^ or lump sait^ is made from brine by a boUing
heat (i*. «. 5226° Fafir. in faOy satCfrated brine) until 6n]y so mucb
water is left as is barely sufficient to cover the small fiakey
crystals that have fallen to the bottom of the boiler. The salt is
then put into conical wicker baskets, and after being drained, is^
dried in stoves, Where it loses about 1 -7th of its weight. - ^ . .
Cheshire common salt is made from brine boiled until it is
brought to th; point of saturation, and the evaporation linishedby
a heat of IffO^ or 170° Fahr. It is in quadrangular hoppers,
close and hard in their texture ; it is drained but not stoved.
Cheshire large grained Jlakey salt^ is made from* B»riue evaporated
at a heat of 130° or 140° Fahr; It is ' rather harder than com-
mon salt, and approaches to a cubical form.
Cheshire large grained ojr Jishery. salt is made from Oriiie evapo-*
rated at a heat ot 100© or 1 lO^ Fahr. the proems lasts for fi 8,
or even 10 da}S, and the salt forms in large and nearly cubic
crystaT^.
Stored salt Is sufficient for dbmestic usies; common salt it
adapted fof sCrikiog and salting provisioas not intended for sea
voyages or Warm climated ; for which purposes the large graiaed*
dr fisfiefysafft is peculiarly fitted-
On the first -application of heat to the brine, a deposit is
formed, whic6 is either removed by skimming, or allowed to sub^-.
side along with the salt fiist formed and then raked nut. Some
brines scarcely require any of this clearing of the pan ; some part
ho>^ever sticks to the bottom, and becomes very hard, so that
the panscale, as it is called, must be removed by violence once ia
three or four weeks.
In Scotland the sea water is evaporated from first to laat by a
boiling heatVso that the salt produced approaches te^the eliaractes
of stoved salt ; but iu some places the fires being slackened be-
tween Saturday and Monday, the crystals are considerably ior
creased in sizre, and the salt is called Sunday salt.
At LymingUm the sea water is spontaneously evaporated in
shallow pits to l«6th oliu bulk before it is brought into the boi^i^
lers, where the remainder of the water is entirely evaporated, and
tli0 whole mass of 6alt taken out at once, and removed into
troughs with holes irt the bottoms, thfough which the Bittern or
bitter liquor drains into pits. Under the trougba, and in a line
with the holes, are &ced stakes on which a poition of salt crys*
tallises. These salt cats, as they are called, weigh about 60 09
80lb. When the manulacture of salt is suspeaded'by the coldness
of the weather the bittern is evaporated, during which, some
common salt is separated aiid reserved for the purpose of concen*-
trating the brine in summer. The evaporated brine is thei»
removed into coolers, where, if the weather prove cold- and clear,.
Kpsom salt crystallises, tht qnaiitity of v^hiah is about l-M^ ^
Anat^jtis Of British and Foreign Salt, Sfc, 279
i(He! boiled liquor, and 4 or 5 tons of it are obtained from a
fluantity of brine, wbich has yielded 100 tons of common salt and
<me ton of cat salt. This single Epsom salt being again dit*
solved and crystallised, is called double £p8oni salt. As Bergman
had erroneously excluded sulphate of magnesia from the cbmposi-
iioa of "Sea -water, liis authority has led Aikin to suppose that
either sulphnric acid, or some sulphate must be added to the
bittern to manufacture Epso.m sal^t, which i^ not the ca^e.
In Cheshire the water of the river Mersey is saturated wit^
• rock salt, so that 100 tons of brine will yield at least $3 tons of
common salt, whereas the same iquantity of sea water with an
equal expenditure of fuel would ^produce only 2 tons l^.cwt. of
JtalU
Some attempts have been lately made jto nse rock.salt cr.ushcd
between iron rollers to the packing of prov^s^ns ; but the results
are not perfectly known.
A large proportion of what is sold in London ^s jbay salt is
Ohetfhtpe lal^ge grain or fishery salt : the foreign hay salt is pre-
pared by the spontaneous evaporation of sea-water, exposed in
shallow pits to the sun and air.
St Ube's bay salt contains 9^0 parts in 1000 of muriate of
Soda» 4| of sulphate of magnesia, §3-| of sulphate of lime, 3 of
muriate of magnesia, a trace of muriate of lime, and .0 of insoluble
matter.
St. Martinis bay salt contains 9^9 j ^^^* of soda, 6 sulph. of
jnagnesia, l^i sulph. of lime, 3| mur. of magnesiai a trace of mun
oflkne, and 12 of insoluble matter.
Oleron bay salt contains 9^*4^ mur. of soda, 4| sulph. of.mag*
nesia, 19| sulph. of lime, 2 mur. of magnesia, a trace of mur. of
iime, and 10 of insoluble matter.
Scotch common salt contains 935| mur. of soda, l/^l sulph.
of magnesia, i 5 sulph. of lime, 28 mur. of magnesia, and 4 of in-
soluble matter : the quantity of muriate of, magnesia is, how*
aver^ vBTj variaUe,
Scotch Sunday salt contains ^7)^ niur. of sod^, 4| sulph. of
magnesia, 12 sulj^b. of hme, llf mur. of^nagnesi^ and 1 of inso<-
lubk matter. *
Lymington common salt.contains 937 naur. of soda, 35 sulph. ojf
jofiagnesift, 15 sulph. of lime, ^1 mur. of .magnesia, and 2'of xnsor
Idble matter. Here also the qu^mtit^ of muriate of magnesia if
!i^iable« •
. .Lymington cat salt contains 9&8 ,mur« of soda,. 5 sulph. <ii
jmagnesia, 1 sulph. of lime, 5 mur. of magnesia, and I of insoluble
patter.
< , Cheshire crushed rock salt contains 933| mur. of soda, 6^ snlph*
of lime,3-l6ths mur. of magnesia, l-16th mur. of lime, and 10 of
sAsoluble matter.
Cheshire fishery salt contains 98€| mur. of soda, 11| sulph. of
2S0 Jnafysis ofBrUisk and Foreign Saltf tfc»
lime, I mur. of magnesia^ | mur. of limei and 1 of insoluble
matter.
Cheshire common salt contains 983| mur. of soda, 14^ sulph.
of lime, i mur. of magnesia, \ mur. of lime, and 1 of insoluble
matter.
Cheshire stoved salt contains 982f mur. of soda, l^ sulpb.
of lime, I mur. of magnesia, | mur. of lime, and 1 of insoluble
inatter.
The insoluble matter in foreign salt is chiefly argillaceous earth
coloured by oxide of iron ; in sea salt prepared by rapid evapora*
lion, it is a mixture of carbonate of lime with carbonate of mag-
nesia, and a fine silicious sand ; in that from Cheshire brine, it
is almost entirely carbonate of lime ; in the less pure species of
rock salt it is chiefly a marly earth with some sulphate of lime,
and its quantity varies from 10 to 45 parts in a thousand. Go.
vemment allows 651b. for the legal weight of a bushel of rock
ealt, instead 561b.
The earthy muriates seem to be derived from the mother liquor
that adheres to the salt. They scarcely, form 1- 1000th pari of the
Cheshire varieties of salt ; and indeed if the brine be evaporated
to dryness, it does not contain more that 5 parts in 1000 of
earthy muriates, whereas the entire salt of the sea water con*
* tains 213.
That sulphate of lime is found in a larger proportion in baysalt,
than even in those that are prepared by the rapid evaporation of
sea-water, seems owing to its being either separated from the lat-
-ter brii^es in the clearing of the boiler, a process which cannot be
performed in the clay pits, or to its entering into the composition
of the panscale. The proportion of it is very variable, de-
pending upon the period in which the salt was extracted from thjc
boiler ; for common salt taken out two hours after the first ap-
plication of heat, contained l6 parts in lOOOof sulpbate of lime>;
four hours, 11 parts; and Q hours, only Z\ parts. On the other
band, the contamination of salt with the earthy muriates increases
as the process advances.
The several varieties of salt, appear to. contain nearly the same
quantity of water after they have been dried by a heat of 212^ Fahr«
Pure transparent rock sail did not lose any of its weight in a low
red heat, nor did it decrepitate like the artificial varieties when sudw
denly and strongly heated. The salts that contain muriate of
magnesia are decomposed and deprived of their acid by a I6w
red heat ; large grained fishery salt loses about three parts of
i^ater in 100 dry salt; St. Martin's bay salt the same; Oleron
bay salt 2| ; "Cheshire common salt 1^ ; Cheshire stoved salt J»
The loudness of the decrepitation was in the same order, and
most remarkable in the large graiued varieties.
The proportion of the other ingredients in the muriate of sode
Analysis of British and S0reign SaU, Sfe* 2S1
contained in these salts appeared, from experiments respecting
the quantity of fused luna cornea that they would produce, to be.
really the same in all, and the differences existing between them
for aconomical purposes do not depend upon any difference in
their chemical compositioh, but on the magnitude of their crystals
and their degree of compactness and hardness. Quickness of
solution is, in similar circumstances, proportional to the quantity
of surface exposed, and therefore since the surfaces of cubes are
«s the squares of their sides, a salt whose cubic crystals are of
a given magnitude, will dissolve four times more slowly than one
urbose cubes have only half that size ; of course the large salt,
when used for packing provisions, remains permanently between
the layers, or will be very gradually dissolved by ibe exuding
fluid ; on the other hand, the smaller grained salts answer equally
well, if not better, for the purpose of preparing the pickle, or strik*
ing the meat.
It was conceived that the hardness and specific gravity of the
- several varieties of salts might be, in some degree, connected,
Muschenbroeck makes the specific gravity of artificial muriate?
of soda to vary from 1918 to 2148, (water being lOOO) the mean
of which is 2033; Sir Isaac Newton states it at 2143, and
Hasseufratz at 2200.
• A piece of foliated rock salt, perfectly transparent, was weighed
in alkohol, and its specific gravity was found to be 2170 ; a less
pure specimen, more approaching to a fibrous fracture, had the
specific gravity of 2125 only.
The specific gravities of the artificial varieties were investigated
by using a glass globe, with a long stem or neck ; the globe held'
16 cubic inches of water each weighing 252^ grains at 60** Fahr*
and from the line where the water stood in the neck about half *
an inch from the globe, the stem was graduated upwards into
100th parts of a cubical inch. Sixteen cubic inches of perfectly
saturated brine was poured into the vessel, s^id 400 grains of
the salt to be examined was then added, and the air adherent to
the salt dislodged by agitation. The 400 grains of the less pure
rock salt broke down into small fragments, occupied 75-lOOths of
a cubic inch, hence its specific gravity was 2112 ; stoved salt, 75^^
sp. gr. 2112; another sample of stoved salt, 76, sp. gr. 2084;
common salt 76, sp. gr. 2084 ; grained fishery salt 83, sp* gu
ISO9 ; another sample the same ; St. Ube's bay salt 32, sp. gr#
1932. Hence the specific gravity of rock salt appears to be di-
minished when broke do>yn, probably in consequence of the air
which the fragments envelop, and which cannot be entirely se-
parated by agitation. The smaller grained salts are however
certainly specifically heavier than those which are composed of
larger and more perfect crystals.
These experiments show that little or no difference in specific
282 An/ilysis of British and Foreign, Salt^ Sfc»
gravity is discoverable between the large grained salt of Britislit
and that of foreign manufacture, and even if no superiority be
♦laimed on account of tfie greater chemical purity pf British s^lt,
it may safely be asserted that the larger grained varieties are
fully equal to foreign bay satt as to their mech^ical properties,
and the prejudice in favour of the latter may be discarded a^
imaginary, '
The method of analysis adopted in examining the several
varieties of muriate of soda, was to pour 4 oz. measures of al«
kohol upon 1000 grains of the salt (dried at ISO*^ Fahr. for 2
hours^ digest th^m for some hours, and wash the undissolved
portion with four ounce-measures of alkohol ; by this means the
earthy muriates were separated and their quantity could be as*
certaified by ulterior experiments, for which w« must x/^v to
the original. The undissolved residuum was treated with 16 oz,
of distilled water, and the still ipsolpble mat^ washed with fresh
additions of water. The solution was precipitate^ by c^rb&nate
of soda, and the precipitated earths were treated with an excess
of sulphuric acid, which excess was afterwards got rid of by.
evaporation to dryness, and the total weight of the sulphates
ascertained, to which that of the earthy muriates, and xnattet
insoluble in water being added, the remainder was assumed as
that of the muriate of soda- contained in the salt that^ was ex*
amined.
' Various curious methods are mentioned by which the propoc'*
tions of the several ingredients were corrected, but they are loo
long to be here inserted. It is suiScient at present to remark tha|
the proportion of the. earthy muriates heretofore given is in fact
only 5-6ths of the real quantity.
Some brine from North wich pumped out of a mine of rock salt
into which water had been allowed to flow, and which was of
covrrse perfectly saturated, had the specific gravity of 1205
at 5€? Fahr. Eight ounce-measures, evaporated to dryness yielded
1 230 grains of salt which contained 2 parts in 1000 of caihouate
of lime and oxide of iron, 5 of the muriates of lime and magnesia
in nearly equal proportions, 19 of sulphate of lime, and 97^ o£
muriate of soda.
The mother liquor or brine that remauiSt after all the comnioii
salt which.it is thought worth while to extract is separated, had
the specific gravity of 1208 : the dry salt from it contained 35
of muriate of magnesia, 32 of muriate of lime, 6 of sulphate of
lime, and 9^7 of nluriate of soda.
The clearings of the brine contained SCO of muriate of soda^
41 of carbonate of lime, and 15^ of sulphate bflinie.
One specimen of panscale contained 950 of muriate of soda, lO
of carbonate of lime, and 40 of sulphate of lime. This variety
is for med when |;he brine being perfectly saturated does not dis-
Anafi/sis of British and Forci^ Saliy ^-c, S8S
solve the muriate of soda carried down with the sulphate oT
kxne.
Aootfaer s|»ecim«n ofpanscale contained 100 of muriate of soda,
1 10 of carbonate of l^ine, and 790 of sulphate of lime. This
i$ forn)«d v^ben ihei^rifie is not saturated and of course acts, when
admitted into the pan, upon the muriate of soda which the pan-
scale contains^ .
Salt oil, or mother li<quor of sea water from Scotland, had the
sptoci^c gravity of IS^f, the dry saJt of it contained 874 of mur
hate of magnesia, 70 of sulphate of magnesia, and 56 of muriate
•f sodfei. '
Salt brme, or liquor that [drains from Scotch salt, had the spe-
cific gravity of only 1158. The dty salt of it contained 205 of
muriate of magnesia,*! 3 5 of sulphate of magnesia, and 660 of
muriate of sodcu
The mother liquor, or bittern pan of Lymington had the spe-
dfic gravity of 12S0; a -quantity of sulphate of magnesia ht«l
crystalhsed in the bottle. The dry salt contained ()40 of muriate
(of magjiesia,>2()0 of sulphate of magnesia, and 100 of muriate of
soda ; so that it dift'ered very mu^rh from the similar fluid sent
from ScotUnd.
• Lymington pansc^le contained 29 muriate of magnesia, 1 8 of
desiccated sulphate of magnesia, 127 of the carbonates of lime
and magnesia, 2l6 of sulphate of lime, and 6l0 of muriate of
soda.
From the very near approximations of the proportions between
the sulphate of bary tes and ammoniaco-magnesian phosphate ob-
tained in the analysis of all these products of sea water, to those
which result from the decomp6sition of two equal quantities of
sulphate of magnesia, it may be inferred that they contain no
sulphate of soda, which was particularly searched for, because
it is stated to be one of ibe ingredients of sea water, by the
Bishop of Llandaff, and other chemical writers-
Obferoationsj-^Jht above experimental investigation of the most
generally useful salt, is highly important in a commercial and po-^
litical view, as it tends to exempt us from the tribute we have
long paid, voluntarily indeed; to foreigners for bay salt, which we
do not hesitate to say, in more positive terms than the modesty
of Dr. Htnry would permit him to use when speaking of his own
experiments, is here demonstratively proved to be injerior to salt
ctf our own manufacture.
aavatMBsneB
Qn tJie Loss o/JFeig/U -which takes place in cmtking jinimal Food.^^
PkU. Mag. No. 14S.
Is whatjfever way the flesh of animals is prepared for food, a
i84 Thj Jrt of Printi$ig (M Sion^y SfC,
considerable diminution takes place in its weight. The foHowhig
experiments were made in a public establishment to serve a pur-
pose of practical utility.
28 pieces of beef weighing 2801b. lost in boiling 73lb. 14of .
or 26f per cent.
19 pieces of beef weighing ipolb* lost in roasting fillU $oz»
er 32 per cent,
9 pieces of beef weighing 90lb. lost in baking 27lb. or 90
per cent.
- 27 legs of mutton weighing 260lb. lost in boiling, and by hav.*
ing the shank-bones taken away, 6Slb. 4oz. ; the shank-bones
were estimated at 4oz. each, so that the real loss by the boiling
was 5'5lb. 80Z or 2li per cent.
35 shoulders of mutton weighing 3501b. lost in roasting 109lb«
lOoz. or 3 li per cent.
16 loins of mutton weighing t4llb. lost in roasting 49lb. I4o2«
or 35| per cent.
10 necks of mutton, weighing lOOlb. lost in roasting 33lb«
60Z. or 32i per cent.
It is therefore more oeconomical to boil than to roast meat ; but
in whichever way it is dressed, there » lost from 1-5 th t« U3d of
its weight*
0&«^iT/z^tOfi«.—- Independent of the smaller loss of weight that
takes place in the boiling of meat»' it must also be observed that
the juices of the meat are also rendered edible in the broth fur*
nished at the same time, by the addition of a few vegetables ;
whereas in roasting meat, these are evaporated into the air ; it
must however be confessed, that there is reason to believe the
roasted meat is the most nutritive. .
On the jifrt of Printing upon Stone. — Phil, J man* No. 1 Ig*
It is necessary for the stone to have a close texture, to give a
clean impression. The ink, which was considered a great secret, is
inferior to coloured turpentine, copal, or lac varnish. Muriatic acid
is preferable to the nitric, as it is not only cheaper, but also does
npt act upqn the resin or wax that forms the varnish.
In some specimens of marble there are veins that arc^ left un-
dissolved by the acid. Some pieces of limestone from Clifton,
near Bath, take a tolerable polish, and readily dissolve*
The easiest method is that of Chauvron, on stone, or even lead.
K wetting is not sufficient to prevent the ink from adhering to the.
block, it may be sponged, and yet enough of the ink will adhere to
. the figures* ■
. Observations.'-^An aceoufit of the origin 4tnd- progreis of this
art may be seen at p. 138 of the present XQlume*
( «»5 )
AGRICULTURE.
Circumstances relative to Merino Sheep, cKiefiy collected frtm the
Spanish Shepherds, who attended Flocks to this Country, By Sir
' Joseph Banks, JT. B. — Communications to the Board of Agri-
culture, vol. 6, part 2. ,
It is well known that the care of the king^s Spanish flocks has
been entrusted to Sir Joseph Banks ; and this situation afforded
him an opportunity of learning many circumstances relative to
tiiA management of sheep in Spain, from the shepherds who came
over with the PatUar flock presented to his majesty by the Spanish,
junta of government. These circumstances are communicated to
the Board of Ajgriculture in a letter addressed to Sir John Sinclair,
the president, and form the article under consideration.
. It is stated, that a considerable part of Estremadura, Leon, and
the adjoining provinces, is appropriated to the use of the Spanish
flocks, which are incorporated under the name of the ^' Mesta,"
and which are driven for pasturage from one part of the country
to another ; and so careful is the police to guard them from inter-
ruption, that no other travelling is allowed on the same roads,
while the sheep are on their journey. The country on which they
are depastured, in both their summer and winter stations, is sepa-
rated into divisions, each capable of maintaining al^out a thousand
sheep ; and every proprietor possesses as many pf tl^ese as will
maintain his flock. la the winter and spring, the flocks remain
in Estremadura, but at the approach of summer they travel to
Leon for the sake of cooler and fresher pastures on the moun-
tains ; and the shearing takes place during the journey : in Sep-
tember tliey return. The flock of each proprietor is called a
Cttvagna, and is separated into sub-divisions of one thousand sheep
each, to which are allotted Ave shepherds and four dogs, who
attend their respective divisions during the journey. And it ap-
pears, that by the laws of the Mesta, the entire management of
the sheep is confided to the care of the shepherds, -without admit-
ting any interference on the part of the proprietor, to whom no
profit accrues except what is derived from the wool, the carcasses
of the cnlled sheep being consumed by the shepherds, and uq
account rendered of the skin and tallow. The profit to the pro-
prietor is estimated at from fi\e to ten per cent. And when the
flock is increased to the greatest number the allotted space of
ground will support, it is the business of the mayorel, or principal
shepherd, to prevent any farther increase by killing the lambs m
J^o. 26\— Vol. Yi, 2p
i^6 Sir John Sinclaiic on Sicilian Wheat, if-c.
aoon as they are brought forth ; and those preserved are made W
suck of two or three ewes. The "change of pasttive is stated to
have no influence upon the wool, but is resorted to merely for a
supply of food. The wool of the dilpBrent iloCks differs much in
fineness of pile; and the piles of Paular, Negrette, and Escurial^
which were reckoned the fhiest, were -withheld from exportation,
^nd retained for the royal manufactory of Guads^laxara, ever
since it was first established. ThcPUular flock consisted of 36,000
sheep, and belonged to the Carthusian monastery of that name^
but was purchased by the Prince of the Peace soon after hi»
advancement to power ; and when his property was confiscated,
^came into the possession of the government. The number sent to
the king was about 2000 ;,.which were selected by the shepherde
fVom eight sXib-divisions, in order to choose young, well shaped,
and fine-wooled animals ; and nearly one fourth of these died
before their arrival at Kew.
Sir Joseph Banks observes^ that though several of the eontineihi
tal nations have imported Spanish sheep, yet none of them pos^
sess the complete and unmixed race of any one cavagna or flock;
and that this circumstance was never regarded, till the king ob*
tained from the court of Spain, in 1788, a little dock of 4 rams^
3o ewe^^ and a manso (or wedder), which had made a part of the
Negrette flock ; and which have been kept unmixed with other
breeds, by the special direction of his majestyr
* The rest of the communication details the prices which the
king's Spanish sheep have fetched at the annual auction, einee it»
establishment in 1 804 ; and some eulogies on the national benefiti
to be derived from the introduction of the Merino breed int»
England »
K
Observatio7is.'— There is so little novelty in the ciretimstance^
respecting the sheep management of Spain, which are detailed in
this article, that we are at a loss to conje<;ture how Sir Joseph
Banks should deem them worthy of an q^d'o/eommunicfttioR to
the president of the Board of Agriculture; though it is easy t»
account for ikeit publication when' they had been' so ccmimHm^
cated ; for something must be given to the public by the- Board, in
return for an aimyal parhamentary grant of 3000/. out o^ th€
Exchequer.
On Sicilian Wheat, — Queries from Sir Jouir SiNCiAiifc, wUk Am^
^iwers by the Phince di CASTELCiCALiir — Commivmcetti^ns i^
the Board of Agriculture, vol* 6, part 2*
^ The object of these queries appears to have been to ascertam
what kinds of wheat were culti>:Ated in Sicily> 9fDd whether i^
Sir John Sinctiti^ on tie S]»ai^^$ Grain tilled Escanda. 96f <
iRp<ptt)d bci possibU to pr€M:ure from thence a change of seed for the
life of/Gre»t Britain* The Sicilian Bobli^^maD) to whom tho^ were,
addre$9edy.sUU«9 that tbe pi*ocl.vi(C^.ot'hiciiy £» always suOi^efitly;
abundant to allow of much exportation, though probably in a less
degree than in the time of the Roman Empire. The wheals usually
Cultivated are divided intoivhiteot *o/fU' heats, w^ich are generally
sowed in light uplands, and into hard wheats, which are sown oil
ail soils ; and three varieties of the former, and nine of the latter
«rd particularly described. The white wheats are not thought to
be wkH' adapted to the climate of England, though the red wheats
may succeed very well ; the strong red wheat is supposed to b^
thesame which is cultivated in Flanders under the name oi Island
wSSffT'TTie' only spring wheat cultivated in Sicily (there called
Tumpnd) ,is j^ red grain and hard, and is sown in March, and th^
Jr6dtiCe is generally comiderable. The ports where ir heat and
flour tnay be en>barfted itj Sicily, .and the prices in the money o{
the country, may be learned by a reference to the original article*
Ohmrtatkmif^To tholgb who advocate the necessity of a changt
<tf teed oorft, the enquin^ife bf Sir John Sinclair will appear impcnrti-
ant and utriotic. m But wbethbr An advaatageeus thsm^ can be
abtaioed from Sicilycao^niy be determined by actual experiments
We eoUeet from the article that eome sved 6i eadi kind ot SiciliaAi
%heas> was to bd seitt to the barant^t^ arid a future Volume of the
]Mpen oithe bimrd«will> doubtless, coataiil an account ofrthi
iiscciveriesof tlie ^iroftid^inthispai'tiottiar. . [
.1
_ _ -_■ ^..^ _w_^
HivU regarding a Spanish Grain called Escanda. By Sir JoifSt
, ^ Sinclair, Part, — Communicaiions to the Board of Aj^rkulture.^
vol, 6, part 2.
Thi pr^idefifl of the Board of Agriculture obtained his inibrma^
lion respecting the existence of this grain from Admiral Apodaca;
the picsent minister from the Spanish junta, who has promised ta
iead ever a quantity of the seed.
The Eseanda is considered peculiar to Asturias, and to be
vnknown in other provinces; it grows to about the size of common
wheat;'the ear is thick, long, and quite white ; the grains white and
rather long, with a very downy point, growing in pairs ; it issowa
in Deeembeff and is th« iast to ripea, and requires good land, or a
rich calcareous soil, for it will not grow in places that are sandy.
The ears are cut off from the stalky which is thrown away on
account of its harshness; and some gathered it by hand. The
grains are forced out of the ear with difficulty, sometimes by a mill,
aind sometimes in a mortar, and are afterwards ground in a com"
jDon mill into flpur, ai^d the bread is represented to be very whitfi|
k V %
i%9 On the Use of Barley jbr Hcnei^
dry, and pleasant, and very nourishing, but requires much labouf
in the kn«.*ading on account of the small quantity of water put tSr
it; thirty-two pints being sufficient for twobusheb of flour.
Observations. — As far as we can forma judgment of £«c(iie(2a from
the imperfect description of the Spanish admiral, it does not
possess any valuable properties to recommend it to the notice of
the British farmer;, and though it might perhaps succeed in the
genialclimate of Devonshire, and in the Southern parts of Ireland^
it can never become an object of general culture.
On the Use of Barley for Horses, Dravm, up by Order of th€
Board. — Communications to the Board of Agriculture^ vol. £•
part 2.
The practice of giving barley to horses is asserted to have been
a very ancient practice ; and to prevail at the present day in
£gypt, in Spain, and in Barbary ; and that the famous horses of
Arabia have the same food. And the use of it in these countries
is said not to have arisen from oats bdng unknown. Homes in
Portugal are also soiled with green barley ; and throughout the
^hole of Turkey, winter barley is their usual food. And common
Imriey has been used in the county of Norfolk for the same pur-
pose ; but this is generally steeped, and spread abroad for a few
days.
It is, however, to be remarked, that the barley which is used
as food for horses in the southern countries of Europe, is not the
Common spring barley usually cultivated in England, hntfaur or
'six-rowed barky, which is cultivated in Scotland under the name
of Bore or Bigg, all the kinds of which will stand the winter; but
the full six-sided is stated to be the legitimate food for horses. It
is asserted, that the partial cultivation of this kind of grain is
solely to be attributed to prejudice, since it is well known that it
produces more seeds than barley, and is less injurious to the
ground, and may be sown on the same ground successively > with-
out either lessening the produce, or impairing the quality, pror
vided the land is fallowed before winter, and twice ploughed be-
fore sowing, with a sprinkling of dung. Some Grecian barley
had been sown by Sir John Sinclair, at Thurso, but the crop was
inferior to Scotch bigg.
The sowing of winter barley is strongly recommended, as not
only proper for soiling horses, but as the sort besta^dapted to the
spring food of sheep ; and it is added, that the being eaten off by
sheep at spring* will not prevent a fair produce ; and that^ in oae
e;Kperimenty it amounted to ireiie quarters per acre. . „.
The course of husbandry recommended for the introduction of
spring bartoy is, .1. turnips; 2. barley or oats; 3. clover; 4.
wheat ; 5. winter tares; and then buck wheat to plough in for
6. winter barley.
Ohsej-vations. — ^The studied panegyric of a production, scarcely
known to the south of the Tweed, sufficiently evinces the nativt
country of the grain recommended; but the liberal Efiglishmm^
will not receive it with counter-prejudice. The winter barley
forms a very valuable part of spring food for many purposes, and
may be cultivated with much advantage in all situations where live
stock are supported with difilculty at that season of the year. Of
the merit of the corn as a substitute for oats, we are not so firmly
persuaded as the right honourable president of the Board.
as-'
On nakedBarlei/. By Warren Hastings, Esq. — Cwnmurdcatwiu
' to the Board of AgricutturCy vol. 6. part 2.
This distinguished character writes to the president of the board
Aat he has cul titrated naked tarley about twelve years r imvnig
received the first seeds of it from Mr. Pacey, an eminent farmer ia
Glocestershire^ under the nanfte of black barley; though;, from fla
resemblance to wheat, he would rather have called 'it barley wheat;
but he adopted the Qarno at the head of the communication out of
deference to the Board of Agriculture. The original stock mm
53 grains, which were sown in the fruit garden, and the first
record of its produce was 10^ bushels in 1799$ which had increas*
cd to 36 bushels in the following year, since which time it has been
-sown instead of common barley. The quality of the gr^in it
asserted not to have degenerated, but the assertion is made in
1809, with a confidence something abated from that of the preced-
<ingyear; and the only change of soil has been from the higher to
the lower lands, and vice versa^ on the domain at Daylesford. It
was sown at the same seasons with other barley, but no trial, to
ascertain the relative quantity of produce has been made with any
satisfactory result ; butin 1805 it was believed to be rather superioo.
Th^ straw is said to be as good, if not better, for cattle, than that of
common barley, and the weight of an equal measure to exceed in
the proportion of 5 to 4; and as an exhausting plant it is not
deemed worse than common barley ; and all the grasses arc found
to Uirive well under it. Naked barley has not found a purchaser
when offered in market, but Mr. Hastings cultivates it for the sole
pui*pose of converting it into malt, for which he considers it parti-
cularly adapted, as he has seldom ont graii^ to bt defactiva i|i
Ycgetation at themi^lt-house*
#96 " C^hhdMt^d m GredianbarTt^.
The vrritcr concludes by expressing his decided eoniricti^ft of
Ihc great utility And importance of the graitt, and declares his
intentionof exteadingfais.culture of it beyond the quantity required
for his own, that thesurplus may be for sale at the disposal of tbi
Board, lie considers it to be the corn, which, next to rice, gives
the greatest height of fiour per acre, and it may be eaten with no
Other preparation than that of boiling, and requires little or no
dr&ising at the miily having no husk^ and consequently producing
IKi bran»
ObstroatioM, — Attention is never withheld, when the call to
teceiye information proceeds from Warrm Hastings. We wish,
however, that he had favoured the public with the Lihnean defini*
tion of the grain ^^ recommends to general .culture ; as naked
barley is not sufficiently descriptive of the plant, though it ha>
xvceH^ ihe authority of the Board of Agricuttuce* But when it
is more widely cultivated, it will be better known, and we have
jiohesitation in pronouncing that the desire of extending the culti-'
vation of it will be bpyond the power of Mr. Hastings to supply
the s^d. '
e«f9BS9»eBES9KesatBaaes«9sa9nfms9Hi^^
4^: GiTCMm Bdrlty. By ColovxI' MItfoiip* — C^nmumcati^tm
: ' to ike Board qJ Agrkukure^ vot* 6. fart 2*
V^nti circumstances commcmicated in this article were €oUectefl
from conversations with Mr. Hawkins, who travelled with the )at«
^Pmfessor Sibthorpe, during his last botanical researches in Greece
and Turkey.
^ It is 'Stated, that there are 4wo %at\» c( barley €«hivated in
• Greece, the flat or two*rowed, our common spring barley;^
snd the six-rowed or round-^ared, which is the same as win*
ter barley or bigg. Both kinds arc used for making bread,
but the spring barley is preferred : the other is less produce
five, though specifically heavitr^ The spring barley can only
be cultivated on the high lands, but the winter barley 80stuA»
ttll extremes of climate : the latter is the common horse-food,
and esteemed the best, the former being reckoned to producii
asthmatic and ricketty disorders; and during three weeks m
March and April, the horses of the Levant are fed upon greea
winter bariey. In Attica, the price of barley is half tliat of wheat,
and the price of oats half that of barley ; one bushel of winter
barley being reckoned as nourishing to a horse as two of oats.
The weight of this barley to that of wheat is stated to be as IS
to 25.
Colonel Mitford made many attempts to raise Orecian barley
iatbiscoantryfroA seed brought over by MnHawkins^ buttvm
Cn the Use rf Sodp^dker$ Wmtt Jlthes as a Manmre. fft
^ tevetitl yMivs obliji^d to gather it ia an unripe state or aecbunl
<tf the extreme ^voracity with vrhkh it was devoured by birds, m
0i>n9e«[uence of becoming ripe earlier than other grain. Afktm
repeated trials^ he succeeded in obtaining .a crop of the six-rowcd
Greeian barley, sowed in the same field with common barley^
The produce was, as nearly as could* be, the same as our nativit
grain ; but he thinks 'it loses the power of ripening early, after i^
becomes accustomed to the climate by rep<;ated sowings* ' >
-Iw.
Obs€rv€ttiom, — It is to be regretted that this account was not
furnished by Mr. Hawkins hiraselfj instead of being detailed ^X
second-hand by Colonel Mi tford. It is, however, more accurate
than could have been expected in an indirect communication :
^d. as to the qualities of this winter barley as a food for horses,
^e have the assertion of Colonel Mitford that he has given hisown^
horses the common spring barley for many years, without pKH
ducing any injurious ejects.
CMtJknae of 8<mfHimker£ Wms$9 A$kes^ commmly ctdiei
Waste, as a Manure. Drsaxm. up bi^ order of the Board ifAgrif
culture, and pubUsked by its direct ion^-^ommunicat ions to thtr
SoardofAgriadinrttviL&^part^ - ■-
. The^ Board having fovnd that the . produce cf doap-makeiV^
waste ashes amounted^ in London, and its immediate neigh*
bourhood) to more than 20,000 tons per annum, and ', being
convinced that this quantity of valuable manure w^ould be
«a object' of coaiiderable importance to the national agncttitai^,
if brought into more general use, were desirous of giving as muck'
publicity as possible to their observations on the subject, it ia
MmaiiEed, that the distinction to be found in soap^ashes dependa
«pon the sort of alkaline salt used by the soap-boiler ; and that
wh«a k^ and barilla are used, they are found to be twice ao.
alrang at die peiuse of common pot-ash, and that from hence aristf
Che tdbifietent reaultt obtained from the use of them In dtifereat
pants of the kingdom. The soaper's waste of London is stated to
cohsispl wholly o^ the le&se ei kelp and barilla, and yielded, whaii
analized by Mr, Baty, 91 parts out of 100 o£ calcareovs maltter }
and will consequently be advantageously applied wherever calca^
reous matter is wanted in lauds, and will serve the purposea of
liming ; and the small quantity of alkaline salt and gypsum it
contains will render it much superior to common calcareous mat*
ter, as *a top dressing for every kind of grass. This waste haf
been found to answer best of all manures on a peat moss, in strong
<;^ldsoils; in Surry^ wh^ut it was applied in the q^uantity of tw»
I I
jt9S T, W. Coke J Esq, OK Experiments on long Dung.
or three cart-loads to the acre ; and in Lancashive it was fotfnd '
Tery goo<l and durable on dry pastures : it has also been used with
success in other parts, and the quantities applied have been as
▼arious as those of other manures* It is generidly reckoned bettef
fat pasture than arable, and crops of clover hay are said to have
been doubled by it ; and is particularly calculated for mixing
with various composts. The price varies in different parts, ac-
cording to the demand, and the nature of the materials^ used ; as
in Surry, about Is. a bushel ; in London, 5s. the cart-load ; ilnd
in Glocestershire, 8s. the waggon-load ; and in Suffolk, where the
soap-makers are farmers, th«y will never sell any. The effect
produced by this manure is asserted to be admirable both on pas-
ture and arable : it destroys slugs and vermin of every description.
And the Board ofifer it as their opinion, that the farmers in the
vicinity of soap-manufactories may avail themselves of these ashes
as a manure without the smallest apprehension of loss, and with
the fairest prospect of considerable benefit.
Ohsetvations, — The recommendation of the Board for the use of
diese ashes is founded on the soundest chemical principles ; and
we have no doubt but that the experiments likely to be tried will
be attended with the expected favourable result.
Queries regarding Experiments with long Dmg, •with Answers.
By T. W. Coke, Esq. M.F. — Communications to the Board of
Agriculture^ vol. 6. part 2.
Ik reply to the queries on this subject, Mr. Coke states, Uiat
lie was induced to make experiments with long dung, by Miw
Davy's lecture on the subject before the Board of Agriculture, in
I80S ; that the dung was filled into the carts quite fresh, and the
quantity from eight to ten loads per acre : it was laid on in th«
beginning of June, and immediately spread and ploughed in, and
the land sown with turnips, which entirely escaped die fly. Th«
crop was better than had been produced in the same field for two
and thirty years, though the manure laid on was not more than
half the usual quantity. The profit could not be'ascertained be-
fore the sheep fed on the turnips ivere sent to market.^
Observations, — ^The theoretical opinions in favour of long dung^ '
which have been too long slighted, are now borne out in practice
beyond controversy, by this decisive trial of Mr* Coke, of
I^olkhan^a
( ^9^ )
fm
BSfil
m
Wh Irrigation. By G. R. Eyres, Esq. of Lynford Hally Norfolk^
— Communications to the Board of Agriculturey vol. 6. part 2.
•fhe writer states that he had justcompleated 23 acres of water
meadow, nearly the whole cf which was in a very unproductive
State ; part being a tough covert, part a moor oven-un with rushes,
and thfe remainder gravelly, covered witH fern and bushes, except
a poftioii of low meadow; From the natural situatioii of the land^
part of the water was disposed in catch work^ and the remainder
formed ihto bods, tht? turf being in the first instance pared eff by
the breast plough, and laid in again as soon as the beds werd
formed* As immediate produce was ndt the object in view, little
attention was paid to that for the first season, the owner consider*
ing winter waterings for the purpose of procuring early spring feed^
to be the grand object of irrigation* ^ The expence was about six-*
teeii guineas per acre, exclusive of masonry knd carpenter's work
for the drains, which amounted to about two guineas per acre
liiore. 'there was a fair promise of a luxuriant crop the 9econ4
sei^h, lUid the result is to be communicated lo the Board.
Observdtioia, — ^Thei^ is nothing either of novelty or information
In this article, biitthe writei' was rewarded with the gold medal
by the Boatd for introducing irrigation into a part of the country
where it was wholly unknown.
On the Maple Tree», By James Hall« Esq* — Commumcatians to
tke Bomtl of Agriculture^ vol. 6. part 2.
' Tttfc writer, expressing his stirprize that the cliltivatioa of the
sugar maple should be so little attended to in the Highlands of
Scotland, remarks, that it thrives well in many parts of America^
where the winters are as cold, and the soil not better \ and that
it succeeds in hedge-rows in all exposures, and may be propa-
gated either by seed or slips. But though its growth is rapid, it
IS twenty yeafs arriving at maturity ; yet, before it is half that
age, very considerable quantities of juice may be obtained from
it by boring a hole in the tree, into which a spout is inserted,
with something placed underneath to receive the juice, which
may be collected every night ; when it should be strained and
• boiled in order to produce sugar. The juice of the maplo is said
to flow four or five weeks annually, and an ordinary tree to pro-
duce about 20lb. of sugar ; and to afford also a most agreeable
molasses, and an excellent vmes^ar; the juice hein^ fit for these
purposes, after it ceases to be so for sugar. It is asserted that tlit
No. 25.— Vol. vi. 2 q
29^ Hall m the odxantagH of Heath in feeding of Stock;
tree is not injurrcl by tapf ^ng ; mmI that tbe leaves are very nutr]«
tioiis food tor cattle, ou account of the saccharine matter they
contain.
aapMsakMN«iW«
Obietxatians^ — While sugar can be procured with the 6ame faci*
lity as at present from our West India colonies, it is scarcely
worth the trouble of cultivating it at home ; should, however^
circtimstanccs hitherto unforeseen and unexpected, occur to prc-
friude a supply from the colonies, then the maple may be advan*
lag<^usly resorted to as a complete substitute for a foreign pro-
duce> which is now come into such general use, as to be almost
reckoned among the necessaries of life.
riUh
On the advantages to he derived from Heath in the feeding of Stock,
JSy James Hall, Esq. — Ccfmnmmcations to the Board of Agr^
culture^ vol, 6\ pdit Q»
In the course of many experiments on furze, broom, rushcsi
b<'an straw, and other neglected articles, Mr. Hall had disco^
vered, that if heath be cut when young and in bloom, and the
finer parts infused in a tea-pot, it produces a liquid very grateful
to the taste, well flavoured, and extremely wholesome. And
being anxious to know how far young heath might be useful t9
cattle j he tried the experiment on a cow. When first tied up,
she refused to eat any of the heath, except the very finest part,
nor did she appear to relish an infusion of it aet bel»ra ber ; b«w«
ever, hunger induced her first to drink the infusion, and then to
>eat the heath, and she lived nearly a fortnight on that £Md 6n\y,i
her milk was much reduced in quantity, but was imfutoved in
quality; A similar experiment was made on a couple of sheep
and an old hoi'se, with Jiearly the same efifect.
Being satisfied from these experiments, thfit cattle may be sup^
ported 4br a long time by young heath, Mr. Hall proceeded tp
ascertain how iiiar the plant was capable of retaining its valuable
qualities, when dried and laid up. He Therefore cut some at the
end of summer, and dried it in the shade ; and at the end of two
years it produced an infusjon equally strong and well flavoured as
at first ; and the effect was the same at the end of three years.
It is stated, that if heath be cut when in bloom, and boili^tf
water-poured on it in a tub, there is produced an infusion, not
only rich and pleasant, but capable of being made the basis of
various vajuable liquors ; and that any quantity of young heatk
ftiay be procured by turning the old, which remains on tbe
ground ; and the ashes afford an excellent manure, and generally
cause a fine young crop to spring. up : this may also be cut for
hay at two or three years old, ^nd may be given to cattle wbea
Horses and Oxen eomparedy by the Rev. R. KedLngtom,^ 295
fodder is sciarce ; but when intended for this purpose, it should
fee carefolly stacked and kept close, otherwise it wiU become less
Yaluafale. , ^ '
OA««T<7^/o;w.-*-Thc certainty that heath maybe relied oi* ad A
food far cattle is valuable information in many districts, where
winter food is with difficulty procured. It apj^ars, howcverL
thai the most ad\'atttagcous mode of using hay made from thii
plant, would be to give it c^X into chaff, and mixed up with
other more palatable substances ; for, as Mr. Hall did not pusll
bis experiment of keeping a cow solely upon heath longer than a
fortnight, it may be inferred, that had the trial been longer perse*-
ver«d in, it would have been less successftll. The circumstance
of heath improving the quality of milk seems an argument forgive
iug it to cows at the same time with other foodie which would
prevent a diminution of the quantity.
B^ses and Owat cmpartd. By the firv. R, Keoinoton^ qf
Ranghtttn^ near Bury^ Ssi^QlkJ-^Qmw»mcutiQm. to ike Bmrd ^
~ Agrlemkwe^ vW. 6. fari % t
Thts' gentleman first determined to employ oxen ftt the yeat
1778, but was two years before he could conquer the repugnance
of his workmen : he persevered and stjcceedccT, One pair of oxen
was allotted to a farm of 27^cres of light arable land, ^nd 40
acres of pasture ; and two pair upon another farm of 80 acres o^
stronger arable, and 14 acres pasture ; but the oxen of the two
farms sonaetimes assisted each other, and in this manner performed
all the work and highway duty for four years, ^he oxen wer^
hsniiFilsed with bits in their mouths, and driven in the sam« man-
ner as horses, and in waggonsund carts went single. Not moi«
than two were used at any time in a common single plou^ la
consequence of taking into hand a very extensive farm in 1784|
Mf, Kedington then used boti^ oxen and horses, and found th^
hovses to do quite as much work as the oxen ; bat was obliged in
a few yearsto part with his oxen, because the ^en food be could
raise was not more than sufiicient for his sheep ; and he could not
reconcile himself to diminish the number of his sheep, In 1801,
Be again reduced the land in his own occupancy to about 90
aeie» of arable, 70 of pasture, and ^7 of wood ^nd plantations ;
and he kept four horses, with the intention of gradually exchang-
ing; them for oxen ; but as few are roared in Suffolk, and thosf
chiefly by farmers for their own use, he turned his attention to
bullsy and purchased two of thfce years of age, which had never
been worked. These he broke in oy first making them .walk till
they tvcre somewhat tired, a^d then, by the geiitlesl means, thcj^
2 Q 2 '
296 Sir Joseph Banks* s iMemoir on Seed Grain*
were harnessed and bridled, with bits in their mouths ; and ^
piece of tiiuber, ten or twelve le.»t long, with a strong staple at
one end, was placed in a field, and the bull fastened to it by very
long traces, to prevent the log from hurting him ; and two men
are placed on the sides, with a line fastened to the bit, to prevent
the bull from turning ; and when he goes tolerably quiet, ahorse
>s placed before liira, and they draw the load jointly. Thispror
f;ess, with patience and good usage, was found to be successful ii;
^U cases, even with animals previously vicious ; and it is asserted,
that bulls may be broke in to work with as little, if not less trou-
ble, than coits. This writer is so convinced of the utility of bulb
Sot work, that he has used them constantly since 1801, and pre?
fers them to oxen ; and has no hesitation, upon a comparispn ii^
pyery poipt of vieyv, that they are to be preferred to horses. He
concludes by declaring, that jie would i^pt exchange his four bulb
for "the four best cart-horses in the kingdom.
Observations, — ^The long experience of Mr. Kedington enables
bira to give a decided opinion on the comparative merits of horses
and oxen on light soils, like Suffolk ; but we conceive, an attempt
te extend his practice to deep soils would only end in disappoint-
ment ; and we cannot admit of a pxeferei^ce to bvills oy^r oxen.
0;t Qjsen, jBy Da v;d Barclay, Esq. — Communications to th^
Board qf Agriculture^ vol. 6. part 2.
On Horses and Oxen compared. By Mr^ WhitwQRTH. — Commut
. nicaiions to the Board of Agriculture^ vol, 6. part 2.
Thssb two papers arc so similar in their design, that they may,
with much propriety, be noticed together. The conclusions in both
are in favour of oxen ; in the former the inferences are the result of
experience^ in the latter the deductions of just reasoning. In
Essex, where Mr, Barclay lives, the soil is light,and does not require
vast powers to turn the furrow. And we cannot again forbear to
inculcate that the nature of the sqil should form a chief part of the
consideration whether oxen may be substituted for horses with
advantage upor the whole.
Memoir on Seed Grain. By Sir Joseph Banks, K. B. — Cotfwwu-
nicaiions to the Board of Agriculture, vol. 6. part 2.
It is the opinion of this learned writer, that the attention of tlie
Board cannot be more adyantagcJusIy employed for the public, thai^
jo discussing the question whether the corn and pube which is lc9^
RiT Joseph Banh^s Memoir on Seed Grain* 2j7
and small in size, and consequently separated trom the rest as not
marketable, be not quite as proper for seed, and as fully endowed
"with the properties of the. parent corn, and as likely to produce a.
superior sample, as the heavy and plump grains.
Sir Joseph contends (and we think unnecesarily, because theposi*
tion will not admit of being controverted) that much of the pro.Iuce '
Qf the soil now condemned as refuse, being employ<*dfor sced,woul(l
leave a larger portion of the best corn for animal consumption^
** If, says he, we admit the increase usually derived from the culti-
vation of wheat to be fourteen times the amount of the seed sown,
we must also agree that one fourteenth part of the very choicest of
the produce of every good harvest is annually committed to the
earth ; and inyears of dearth, when speculators increase the breadth
of their wheat crop, a still larger proportion ; should experiment de-
cide that we may safdly substitute in the place of this valuable ar*
tide, the small grains which arc generally destined to the rearing
of poultry, the gain of the public will be immense, and the loss
scarcely sensible." And having stated thus much of the theory,
he proceeds to give an example, and states that in the year 1807,
which was a most calamitous season for peas, the Earl of Winchel-
sea had a peck and a half of shrivelled and unsaleable pulse, (the
refuse of the crop of nine bushels) which in the following spring
Ijie ordered to be dibbled into as much land as they would cover,
which was compleated in April, and the work measured six acres
and thirteen perches ; the crop reaped was 25 J quarters of good
boiling peas, weighing 18 stone 7lb. to the sack. The advantages
which would result to the community if this plan became univer-
sal are then pointed out, and the opinions of Sir John Sinclair in
his publication on the blight, &c. are brought into review. It is
stated in that publication, on the authority of an intelligent farmer,
who had sowed both plump and lean seed, that from their first
appearance, the corn from the plump seed was much more luxuri-
ant, and it continued so, as if it had been dunged, and the other
neglected ; but no account is piven of how long the superiority con«
tinued ; and asserts, that well filled seeds are better calculated tor
pushing in search of nutriment, than grain of a meaner quality.
The reply to this argument is, that a rank and luxuriant crop is
more likely to run to straw than to grain, and is very frequently
deficient in produce.
ObsercatioJis.-^There is certainly some ingenuity in the sugges-
tion of Sir Joseph Banks ; but that thin and lean grains should
produce an equally healthful progeny, with the best samples, is
contrary to the analogy of all other departments of nature. And
we cannot conceive such a distinction between animals and vege-
tables, that what is allowed to be inapplicable in the one ciin b^
tablished in the otljer,
,.. ( 29* )
\
Comparative experiments on the cuHure and appUcaiioH of Kohl*
rilfij Drum-headed Cabbage^ and Sicedish Turnips. Bjf Mr.
John Saddlngton, of Fuichley. — Trana.Soc. ofArts, toL 27*
Tu E land appropriated to these experiments was about two acres
tnd a hall, which had been previously underd rained; the soil was
a loam^ with chiy and gravel undfT. In March I8O6, oats were
sown upon it. at the rate of three buohcls and a half to the acre,
and the produce was nearly five quarters per acre. Winter tares
were next sown, which were eaten off by sheep, and a crop of
■wheat was then taken. The crop being housed, and the stubble
mowed and cleared off, the land was got ready for turnips m the
la^t week of August, and three pounds of seed wt re sown upon an
acre ; and when the plants were just making their appearance,
two quarters of gypsum were sown by band, to pn venl the fly.
The crop of turnips proving very valuable, led to the experiment
T^hich is the subject of the communication. The preference is'
^ven to kohl rabi over drum-headed cabbage and Swedish turnips,
beiog found a prolific plant, and nutritious for the feed both of
slieep and neat cattle, and producing green food from October to
May. In order, however, to insure a succession of keep, seed
should be sown in March, April, and May. Th^ plant is de-
scribed as butting above the ground, with a leaf not unlike beet;
and It is found td^ stand the severest frosts, even when incisions
ace made with a knife two or three inches deep. The plants may
be transplanted the same as cabbage ; and when transplanted at
eighteen incW asunder, have weighed ten or eleven pound*
each.
The mode of culture adopted by Mr. Saddington, for this expe-
riment, was, to sow kohl rabi seed on the 14th of May, and the
plants were transplante<l, at twelve inches apart each way, on the
18th of June ; and averaging the plants at three pounds each, the
troduce was upwards offiftjf-eight tons per acre. ^In March he
ad also sown some drum-headed cabbage seed, and the plantft
'were transplanted the second week in June, upon ridges three
feet asunder, upon land previously dunged, and the produce was
not twaity^ix tons"per acre. . The cabbages were much damaged
by. the caterpillar, which did not touch the kohl rabi on the ad-^
joining lands. In June Swedibh turnips were sown, but two thirds
oi the crop were destroyed by the fly : the Swedish turnips were
not equal in Wieight to the kohl rabi in any comparison. Beside*
this superiority in weight, a decided preference is given to the
kohJ rabi, because there is less waste in eating it upon the ground^
inasmuch as it bu|bs above the soil, while the Swedish turnin
JRrtJ. /* HaM on a Prtjxtrtititnfr^n'BemhStalh for Smp. 559
btilbs in it^ and "when eattm lovel with the ground, becomes a
receptacle lor diit, and coi»eqacntiy no longer regarded tfs
food. '
Ofeen'^/on#.— The public are much obliged to Mr. Saddingtoti
lor recommending the cultivation of so very useful a plant as the
kohl rabi, by an exprriment so decisireJy conclusive. We havfe
little hesitation in saying, that when once tried ona farm^ it Wift
never be-again abandoned, unless circumstances precllide its cuK-
• tore. The unassuming style of the communication affords, tea,
« favourable impression of the writer*
• tWWWMWTj.ii ,j J iiiii'igggaeggBaaeBBagneg^gBigBaagB^^
■
On a preparation from Bean*9iM0f bb a substitute for Hemp. By
the Heo* James Hau, rf fFaitkmmtoWf Esse9^ — ZV«w. Soci
ifArts^ *DoL^7*
The communication ob this subject statn, that ei^efy hetih
plant contains from 20 to 35 filaments or fibres, running up on
the outside, under a thick membrane, from the root to tbe yrttf
top all round, the one at each of the four corners being rather
thicker and stronger than the rest ; and that, with the exception
of the Chinese sea-grass, used at the end of fishing-Klines, these
lilanients of the bean plant are among the strongest yet discovered;
and are easily separated from the strawy part, with a little beat«_
ing^ rubbing, and shaking, when the plant has been steeped teil
or twelve days in wafer, or is damp, and in a state approiiching ih
fermentation ; and, as far as the writer has discovered; washing
and pulling it through hackles or iron combs, first coarse, and
then fine, is the easiest way of dressing bean-hemp. A calcul»-
lion is given, from which it appears, that about two hundred
weight of'this hemp may be obtained from an acre of beans ; and
the fibre is thought to be admirably calculated for being con^
verted into a thousand articles, where strength and durability t%
of importance ; as well as, with a little preparation, into paper
of all kinds.
In order to ascertain in what degree this species of hemp H
liable to injury from different situations, and the changes of th^
jjttmosphere, Mr. Hall exposed one parcel nearly twelve months '
€# all the varieties of the air within doors, and kept another paN
<!fel constantly under water for the same time j and neither of thesfe
was fotind to be injured in the least: the chief diflfetencc waai^
that the parcel kept under water became the whitest of the twof,
9Li\d assumed a rich silky gloss, df which the other \was dfestitutt?.
Jt ie also stated, that it bean-straiy be kept for years under water,
or quite dry, it produces hemp as good and fircsh as at firbt ; but
if the straw be sometimes wet, and sometimes dry, tfae'filttmett&
(500 tf^. Congi^ecty iRsq, on planting OatcSi
ere apt to be injured. If the straw was scattered tliiri on tt*
ground, and exposed to the weather for two or three months, it
was uniformly found that the hemp or fibres are loosened, and
easily separated from the strawy part without any other process
than merely beating, rubbing, and shaking them ; but from the
fermentation that takes place in the strawy part communicating
itself' to the hemp, it was more or less injuredj but never so muqh
tis to render it unfit for making paper. The water in which bean*
straw was steeped, acquired in a few days a blackish colour, but
cattle drank it greedily, and seemed fattened by it. When straw
is to be preserved for bean hemp, it is considered proper that the
beans should be threshed in a mill, and be put into the rollers of
the mill length-ways, and not across the rollers ; otherwise the
straw will be very much cut, and the fibres damaged.
Obseroatiims. — Before we can sanction the discovery of Mr.
Hall by our recommendation for applying bean-straw to the use
he points out, it is necessary that the filaments prepared from it
should be manufactured into various of the articles for which
hemp is now used.
On planting Oaks. By W» CoNGUfevE, Esq. of Aldermarston House f
in Berkshire. — Trans. Soc. of Arts, vol. 27-
This successful candidate for the gold medal of theSociety states,
that since the year 1 802 he has planted more than 74- acres in and
near his park at Aldermarstonwith young oaks; the first plantation
of which, being twelve acres, made in 1802, arc from six to eight
feet high; and most of those planted in 1807, about one foot high.
The whole of the plants are said to be well fenced, and that there i
are more than three hundred plants upon every acre of ground.
The acorns were set by women and children with sticks used in bean
setting, about two inches deep, in rows a yard asunder, and a foot
between each acorn. Except in the first plantation the land was
not prepared in any way whatever: where there was* furze and
heath, the furze was cut down as close as possible, but the heath
was left as a shelter to the young plants. It was conceived that
the heat of the sun was very injurious to young plants, and that
heath or long grass was a great protection to them. In that plan-
tation which was cultivated, the land had been ploughed two or
three times, and about a month after the acorns were set, it was
town with furze seeds> broadcast and harrowed : the furze became
luxuriant and was cut for fuel, but gave such a' shelter to rabbits,
that they proved destructive to the young trees, and w^as conse-
quently obliged to be destroyed: The soil on which all these plan-
tations are made, is a mixture of gravel and clay, andiu a few places'
J
Account of Land gahied from the Sea. 501
almost entirely clay ; about eighteen acres were heath land^ to-
tally uncultivated and unproductive.
Observations, — ^Thesc very extensive plantations of oak well
merited, the reward of the medal, which they obt-ained. Mr.
Congreve's agricultural improvements in other respects, as welfas
in his plantations of oak, need only lo be seen to be duly appre-
ciated by every one who is a competent judge of the benefits
which a country gentlenijan can in this way confer upon the
public.
Statement of drilled and broad-cast Husbandry, By Messrs.
Batchelor, of IddlingtoUy — Agricultural Magaxiney No. S6:
The experiment was made in 1808, on a sandy soil, pn part
of a field pf 16 acres and a half, after turnips fed off by sheep : of
this about 10 acres was taken for the trial, and was sown with
oarley. The drilled barley occupied 5 a. Or. 34r. of ground, and
had 17 J bushels of seed sown thereon; the broad-past occupied
6a. 3r, 6p. and had 22 J bushels sown thereon : the drilled crop
was horse-hoed, and the broad-cast weeded by hand ; and the
eiqjence of labour on the drilled crop exceeded that of the broad-
cast by 5s. 8d. an apre, The total produce of the drilled crop was
27f\vs. 4 bushs. 3 pks. or about 5(ir«. 2 j bushels per acre ; and the
produce of the broad-cast crop was 26qrs. 3 pecks, or about
4qrs^ 44 bushels per acre ; th superiority of the drilled barley
was, therefore, above 6 bushels pi r acre. The time of drilling
and sowing was the^Slh and 29th March : very little difR:rencc
was observed, in either crop, during the growth. In the corn
produced tiiere was not the slightest diftcrence of quality.
Ob^rvations, — ^This experiment gives a result decidedly in
favour of the drill husbandry; but it should be recollected, that
the trial was made on a very light and sandy soil ; and perhaps a
result equally favourable might hot have beci> obtaiijed on a soil
of a ditferent nature.
jiccount of Land gained from the Sea, By Mr, W, LAttRENCE.
— Agricultural Magazine, No. 36.
The lands reclaimed from the sea by this writer are about 100
ncres, and arc situated in Essex, near Maiden. The embank-
UK-nt is made of spil only, not thrown loosely together, but cor^-
posed of the earth which was tiiken frotn a ditch on th« land sid*
fno. 25. — Vol. vi^ ? R
/ •
502 On the management of Cattle in the Highlands of Scotland.
the embankment, and from the sweard and soil taken from off
the foreland on the sea-side. The earth was thrown together to
form the wall or embankment, and after every layer, well rammed
together by the workmen ; and in this manner made so firm and
consistent, as not to have sunk perceptibly, though several high
tides have happened since its completion. No gtass seeds were
sown on the bank when it was first made, because, being so much
impregnated with salt, it was thought they would be burnt up
on the bank by the heat of the summer ; but grass seeds will be
sown at the end of a year, which are expected to produce ttiuch
good sheep food.
Observations, — We record with satisfaction, another instance of
much valuable land being reclaimed from the sea, to the advan-
tage of the community ; ^nd, we trust, also, to that of the indi-
vidual who has conducted the undertaking.
mamesm
\
On the management of Cattle in the Highlands of Scotland.—^
y Agricultural Magazine^ No. 37.
The cows are said to generally produce their first calf at the
age of four years ; and while the price of cattle was low, it was
the practice to kill half the number of calves, and to allow one
calf to suck two cows ; by which means the calves were well
reared, the cows were kept in better condition, and the surplus
milk compensated the loss of a calf; a portion being withdrawn
for butter, and the calf then allowed to take the rest ; but since
cattle have become more valuable, the system of coupling has
been given up. The cows calve from the middle of March to the
middle of June, but the early calves are always esteemed the best.
In the beginning of November they are deprived of milk, and the
cows sent to winter pasture \ the calves are put upon fine pasture
at the same time, where they Remain till the fall of snow, when
they are housed, and fed till May with oat-straw, hay, potatoes,
and turnips. For the firet year, the young cattle are generally
fed on the high grounds, and are afterwards removed to the low
grounds. From three to five years old, their freight, when lean,
may be averaged at 70 or 8Q lbs. per quarter, and their price from
four to seven poitnds.
Observations. — ^This anonymous account of the mai^ageiiiieQt of
cattle in the Highlands of Scotland, has been obviously manafac-
tured from publications to which no reference is made ; though
it can convoy no information to the Scotchman, it may amu^c the
reader on the South of the Tweed.
( 505 )
Ott the mode of preparing French Vinegar, and the different specter
of the article which are manafactured in Trance, — Agricultural
Magazine, No, 38.
It is remarked, that although the word Vinegar implies, that
this acid liquor is usually extracted from wine, yet it is obtained
from divers other materials ; and even from some in which one
would not at first suppose there existed any principles capable of
forming an acid comparable to wine vinegar : it is manufactured
from perry, cider, beer, mead, milk, and even from grain and
vegetables. And though good wine is necessary for the produc-
tion of good vinegar, yet the French most commonly manufacture
their vinegar from their unsaleable wines. Tlie processes pursued
in this manufacture are said to be various ; but the general plan
is, to expose the wine to the contact of the air, and to a heat of
between 20 and 22 degrees of Reaumur's thermometer,' in tuns
not entirely filled, and fermented with vine-branches, grapes,
gooseberries, the lees of sour wine, &c, &c. which materials are
styled by the makers mother of vinegar. And in order to conceal
the weakness of the quality, and to improve the acid flavour,
there is frequently added Indian pepper, and other highly bitter
drugs, which communicate nothing of acidity, but merely give
it an ardent flavour.
The best mode of ascertaining the quality of different vinegars,
is said to be saturating them with potash : an ounce of genuine
vinegar being saturated with sixty grains of potash, while the
same quantity of vinegar, sophisticated with bitter substances,
only requires twenty-four grains for saturation. And the adulte-
ration of viaegar with oil of vitriol is said to be more easily disco-
vejred, since the odour of this 9,cid is immediately perceived, by
casting the vinegar that contains it upon burning coals. It is
fi«lded, that several nations, in default of wine, employ divers
other articles in the manufacture of vinegar, but that liquor of
this description ought rather to be called alegar than vinegar.
Ohcrvations, — This poor, unsatisfactory article, is the only
one we could select from this number of the Magazine, possessing
any claim to origii\ality ; and what claim of this kind it may
have, the writer has not the courage to avow his right to it by
giving his name. The matter it contains is not new to us, though
y^e cannot imraeiji^tely point out the source from whence it is
derived*
2 R 2
( 304 )
Draft and description of a Threshing Mill latelji invented, ffj
\V. B. — Farmers Masazine. No. 4^.
This mill is stated to be the invention of a Mr. Monteith, at
Skirramuir, near Dumblane, in Perthshire. It is almost imposr
sible to give an intelligible account of this machine, without the
assistance of the drawing which accompanies the description. The
principle is, to thresh the corn in a circular box, similar to the
box which incloses the stone* of a mill for grinding, into which
the corn is introduced by the hand, through holes in the top of the
box ; and the threshing is performed by the revolution of four
radii or spokes, projecting at equal distances from a vertical shaft,
which passes through the centre of the box, and may be turned by
water, or by horse machinery. The corn passes through the bot-
tom of the box, which is formed of wooden ribs, not an inch
asunder; and the straw is rejected through a hole in the side, by
the centrifugal motion. The particular machine described is
turned by water falling through a trough upon boards placed at
the bottom oCthe shaft, so as to communicate a rotary motion;
and the effect is' described by the number of sheaves threshed in a
minute, which is too arbitrary to convey any idea of precision.
Observations* — Without intending to derogate from the inge-
nuity of this invention, we agree with the conductor of the Maga-
zine, in entertaining strong doubts of its utility. If water be used,
it may be applied more economically ; and it is obvious, that the
labour must be increased from the want of feeding rollers, and
that the straw will be, in a manner, beaten to chaff.
Thoughts on the periods of sowing Seeds of different Kinds. Bjf
A. M. — Farmers Magazine^ No* 42.
As it is admitted, that the duly adjusting the periods of sowing
seeds for different kinds of crops according to the forwardness of
the season, is of great importance in agriculture, and as the tem-
perature is far from being the same in different seasons at the sara<J
period of the year, the writer infers that the seed time ought to
vary with the season, instead of being confined to any particular
period ; and he thinks that the best standard for determining the
most advantageous period is, the budding and leafing of ti*ees.
The budding and leating of the birqh tree, is said to be considered
in Sweden as a directory for sowing barley ; and it is'recorded in
4hc Amonitates academico that the illustrious Linnaeus exhorted hi»
On the vmpraprieiy of mixing the Seeis of Grasses^ S^c. 30*
Cotintrymcn to observe ^ith care what time each tree expanfls it«_
buds, as infoiTfiation which might lead to the most useful purpose'*.
For these reasons the prudent husbandman is advised to watch
the budding of trees, and to collect from this circumstance the
proper time for sowing, and to make the operations of nature a
calendar for his own labours; and it is contended that more
favourable crops, than would otherwise be obtained, will amply
rew^ard his diliscnce. ,
Observations, — ^There can be no doubt but that nature is our
safest guide in all labours of agriculture ; and the sugsjestions
thrown out in this paper for fixing the time of sowing different
seeds may certainly beobtained by observations cohtinuctl through
a series of years. The analogy between the budding of trees and
vegetation of seeds is striking, and we recommend the hint here
given to the attentive consideration of farmers in general.
Cheap plan of <i Sheep House, By A. S. — Farmer^ s Magazine'^
No. ^2.
• The sheep house recommended in this paper on account of its
comparative cheapness is 85 feet long by 15 wide within the walls,
which are only about three feethigh, of plain rubble work of stom%
with lime mortar. The doors are at each end, sufficiently high
Sot a man to carry in a burden of hay. It is thatched in the
common way, and at each end a circular piece is inclosed by a
wall, six feet high, to preveht the storms from blowing in at tha
doors. The cost of such a building is given at 251.
Observations,: — ^The utility of such a building for sheep in bad
weather is self-evident, particularly in bleak situations; but there
are few parts of England (if any) where a sheep-house of this size
can be constructed under double the estimated expcnce.
" On the improprieti^ of mixing the Seeds of Grasses, when Land is
soxon down for Pasturage, By Mr. James Head rick. —
Fanner's Magazine^ No, 42.
The contents of this paper are given as the mere ebullitions of
agriciiltural conversation ; which, however, were deemed worthy
by Mr. Headrick of being submitted to public notice. It was in-
sisted, that in laying down land for permanent pasture, so as to
derive the greatest possible profit from it, all mixture of grasses
should be avoided ; that the land being sufficiently cleaned* and
aJiurcd, one field should be fully stocked with white clover ; an««
Se6 On the Disease in Cattle catted the Stack SpaW
ther with perennial rye-graws; another with rib-grass ; another witH
wild vetches ; and thus each field should be occupied with plant?
of a different species ; and that the stock should be frequently
shifted from field to field ; which would m^ke them eat with ^
keener appetite, and fatten more rapidly, than when presente4
with a mixture of grasses, which are never changed : for it may
be observed, that plants of different species do not thrive so well
'when mixed in the same field, as when they grow^parately; ^n4
that, when animals arc put into a field containing a great number
of plants, there are always some which they prefer, and select in
preference to others, while those that are n\jccted are trampled
down and lost : but in the plan proposed therp is no rqpm <bf
selectipn ; and by the regular change of the species of food, the
natural appetite for variety receives complete gratification.
— — ^— M— ■ ^lih
Obsenations* — We have deviated from our prescribed rules, not
to notice mere opinions^ unconnected with experiments, because
we consider the present article furnishes some very useful hints on
an important subject, which i^ at present but imperfectly under-
stood.
On the Disease iu Cattle called the Black Spald. By W. F*—
Fafvner's Magazine, No. 42. '
TiiB black spaldy which is also sometimes called the quarter ill,
is a disease which very generally proves fatal to cattle ; and no
certain remedy has yet been discovered for it. It is supposed to
be occasioned by the accumulation of air underneath the skin,
which makes a progress from the extremities towards the heart,
and terminates in death, unless this progress be' arrested. A me-
thod of cutting the skin, to let the diseased air escape, was recom-
me.nded in a former volume of the Magazine, and is said to have
been successfully applied in some cases ; but the writer of this
article states, that he consi,ders the remedy so precarious, that he
had recourse to two modes of prevention ; the first, to let blood
from his young cattle in the autumn, which is considered benefir
cial at least; and the other, putting a layor of tar acrpss the
. back, immediately behind the ribs. This method h^.d l^n prac-
tised with success by Mr. Christison, of Cumbernauld Ho.use ;
• but two young cattle, which had been neglected, fell victims ta
the disease.
Observations, — ^The success of the application of tar as a pre^
iFcntive of this fatal disease, does not appear to b« established
by sufficient experiment to be implicitly relied on ; fpr it is imp<f*
Obsertattons on faying do-wn Mead&w and Pasture Land, SfC. 30J[
sible to say, whetiier the young cattle which were subjected td
the application, might not have escaped, the disease without it.
It may, however, deserve consideration, whether a blister appli*^d
between the diseased part and the heart, might not arrest th«
progress of the disease.
Observations on the use^ ofldme. By O — r — s. — Farmer^ s.MagOr
zincy No. 43.
The writer, being engaged in the improvement of a farm, iMxtir
Ittcr-fallowed a park of ten acres, which was considered the worst
part of the faiin, with considerable care : it was ploughed as de<?p
ks four horses could penetrate with a large plough ; and one half
was limed at the rate of from 60 to 70 bolls per acre, the othet
half being dunged considerably more than usual : t\\e whole wa»
^own with oats, and with rye-grass and cloVer sefed ; the crop was
good generally, but the limed half was much superior to the
dunged. The grass was cut for hay, and the part dressed with
lime still preserved the superiority both in quantity and quiality ;
and even during the winter, had a close verdure and healthiness
upon its surface.
Observations. — We have ever be^n of opinion, that lime caii
lievet be employed upon land to so much advantage, as in laying
down for grass ; and this experiment proves its decided superior-*
ity to dung for that purpose.
Observations on the method of laying dovm Pasture and MeddotB
Land, with an account of some Pastures made ivith the Meadow
JFescue Grass and Clwers. By Mr. W. Salisbury, ofBromp^
ton. — Trans. Soc. of Arts, vol. 27*
The remark of the late Mr. Curtis, in his well-known work on
the British grasses, that several of our native grasses are better
adapted for the purpose of pasture than ray-grass, which is ,the
species generally used for that purpose, is decidedly confirmed
by the experience of the present writer, who has paid particular
attention to this subject ever since the death of his late partner,
Mr. Curtis. Mr. Salisbury expresses his mortification, that after*
so much had been written on this interesting subject, and when
other grass seeds may be obtained, that almost every person should
be of opinion that they cannot be cultivated to advantage, though
fie is ready to admit, there is much truth in it, when they are
f own according to the common practice, which he has convinced
508 Objurations on laying dovm Meadow and Pasture Land^ S^e,
bimsoH to be erroneous. He is fully sensible, that many per-
sons will deem it mailness to sacrifice the benefit of a crop of bar-
ley or oats, where the land is in fine order, and while a good crop
Oi s^rass can be had under it ; but to tiiis he replies, that there i»
no land whatever, when left for a few months in a state of rest,
but will produce some kind of herbage, good or bad ; and ob-
scTves, how extremely absurd it is, to endeavour to form clean
and good pasturage, under a crop that gives as much protection
toevery noxious weed, as to the young grass itself. VVe^ds, it is
remarked, arc of two descriptions, and each requires a diifcrent
mode of extermination : thus, if annual, as the charlock and
poppy, ihey will flour among the corn, arid the seeds will ripen
and drop before harvest, and be ready to vegetate as soon as the
com is removed ; and if perennial, as thistles, docks, couch grass,
and along tribe of others in this way, they will be found to tako
such firm possession of the ground, that they will not be got rid
of without great trouble and expence ; and the subsequent trouble
and expence of clearting the land, is thought to more than coun-
terbalance the profit of the corn.
To fully accomplish the formation of meadows., three things are
itated to be necessary ; namely, to clean the land, to procure
good and perfect seeds, adapted to the nature of the soil, and to
keep the crop clean by eradicating all the weeds, till the grasses
have grown sufficiently to prevent the introduction of other plants.
The two first of these requisites being universally known are passed
over; and the third is detailed, as it has been practised with the
greatest success by the writer. He states, that grass seeds may
Ik^ sown with equal advantage both in spring and autumn. In a
particular instance, the land was sown in the latter end of Au-
gust, and the seed made use of was one bushel of meadow^ fescue,
and one of meadow fox-tail grass, with a mixture of fifteen pounds
of white clover and trefoil : the land was previously cleaned as tar
• as possible with the plough and hatrow, and the seeds sown and
covered in the usual way. In the following October, a most
prodigious crop of annual weeds of many kinds had grown up and
were in bloom, covering the ground and the sown grasses, the
-irhole of which were then mown and carried off the land ; and by
these means all the annual weeds were at once destroyed ; and
"while the stalks and roots of these were decaying, the sown grasses
were getting strength, and the few perennial Avceds which were
among them were drawn by the hand in fine weather. The whole
was repeatedly rolled, to prevent the worms and frost from throw
ing the plants out of the ground; and in the following year, thcr-c
was a remarkably fine field of grass.
Observations, — The method practised by Mr. Salisbury, of lay-
ing lauds down to grass, is highly deserving of imitation : it, ^U^
New Theory i^tJie Diwnal Motion of tit flarth. 3(S
Se found as beneficial in practice' as it is correct in i)ieoryv
The system u&aally practised of sowing clover and rye.grasi
iiinder barley, when it is intended only for a season .6r two to
change the course of the cropj, artd to be returned again to arabl^
4s soon as the clover is iejcha1dste<l, oV (Overpowered by tlie weed&
whirih gro\^ aniongit it, ih'ay b^ hs'efully continued in such cases,
but where land is intjpnded for i^ermanerit pastuni or' meadow,
the method i-ecotilmended iA tliis eominunicatioxi will produce a
inuch better turf^ at a considerably less ex peace upon ilit
whol6,~ahd in a niuch ^Hoirter time ; «nd it appears preferable td
^ow the grass seeds in aiitumn on accdunt of the greater fa^ilit/
bf destroying the anil'usil ^eetis*
iba
mam
NATURAL PHILOSOPHY, ARTS, and MANUFACTURE^
JVnu 'theory 6f the Diiirndl Motion Of the Earth roAnd its Aicis.^ Bf
Professor Wooi>, Richmond j^cademy^ Stati 6f Virginioj-^Fhilm
Journal f No. US.
At the commencement of this circuiai* letter, Mr. Wood states
that he has just published a work entitled " A New Theory of (he'
l)iumal Itotation of this tlarth, demonstrated upon Mathematical
{Principles, from the Properties of the Cycloid and Epicycloid ;
with- an Application of this Theory to the explanation of the
Various Phenomena of the Winds, Tides, and those ^toney^^nd
inaetallic ConcretioiiSi which have fallen from Heaven (thift Atmos-
phere) upon the Surface of the Earth." The idea of this under-
itaking was nrst suggested by the fact that the velocity pjf the top
i)f a carriage wheel in motion is greater than that of the bottom ;
this Mr. W. conceives to be applicable to thai of the earth. TEc
xiioLion of each ^oint on the earth's surface, except the two poles,
being compounded of two motions, one a rotary motion about its
axis, and the« other k progressive motion in its orbit ; Mr. V?»
supposes that it will ** describe a curve of the cycloidal, or ratb^
^picycloidal species, possessing a similar property with the coni*
itiion cycloid generated by a carriage wheel." This condition
being once established for any point, a variation in the centrifugal
force at that point must necessarily follow, and on this principle
this author accounts for the tides, trade-winds, ^c. In order t^
afford a general idea of the principles oh which this theory is
founded, three of the propositions which are deemed the most ini-
portant are transcribed from the work referred to ; but as theas
isahnot be easily understood independent of the diagram by wbicjt^
s5^o. 25.— yoL. vx; a s
^ 1 0 Pro/eMor fFood on the Diurnal Motion of the £arti.
they are accompanied, we shall refer to the original for these, uxA
state the general results which he has deduced from them. In order
to apply the forqaula derived from the last of these propositions
jto the motion of the earth, it is supposed ^' to. move along the
chord of an elliptical arc every twenty-four hoars, instead of the
arc itself over, which it really moves/' From these premises, it is
** deduced that the velocity of any point of the equator at noon is
to the velocity of the same point at midnight as 3718 to 36*02, or
as U034 to 1. In like manner I have found that the velocity at
fline o'clock P. M. i& tothe velocity at one o'clock A. M. as 248*9
to 241*4^ or as 1*032 to J.*' The effect which this difference of
velocities produces on the force of gravity at the earth's surface
is then subjected to calculation,- and it is stated that bodies under
the equator lose a 9375th part of their weight at noon. It i»
then assorted that the efect produced by this difference of gravity
upon bodies situated at the surface of the globe is 306 times a«
great as the effect produced by the attraction of the moon, and
137^ times as great as that produced by the sun. These are the
principles employed by Mr. W* to explain the phenomena of the
tides, trade-winds, and of falling stones. With respect to these
last, he supposes them to be projected into theataaosphere from
volcanoes r ^^^ thttt the -point from which they issued had its
velocity varied during the time of their flight, while the velocity
impressed upctn them at the moment of their leaving the earth
remained constant ; and consequently, that they would descend
at a- greater or less distance East or West f^'om the point of
projection, according to this variation.
Observations. "^The first and strongest feeling excited in our
minds by the perusal of Professor Wood's " New Theory of the
Diurnal Motion of the Earth/' was that of surprize at its having
'obtained' a place in this- highly respectable Journal. This feeUrig
arose from our hope and . belief that Mr. Nicholson's acquaint
'tance with' suhj.ects of this nature was much too accurate atii
extensive to have admitted it on account of either its novelty or
its correctness ; and we conceive that the following reniitrks will
convince all our mathematical readers that oar sui^rise was odt
altogetTjer groundless.
We shall not dwell on Mr. Wood's inaccuracy in confounding
cycloids with epicycloids and epicycloides with epitrbchoids^^ nor
-on his error in making the earth turn the wrong way ; since these
are points, which, however they may betray his want of mathe-
matical knowledge and astronomical precision, do not immediately
'affect the argument upon the theory which he has proposed." But
' the simple statement of the case is tliis : That the velocity of each
point of the earth's surface, as referred to the quiescent space occn^
frofessor JTood on the Diumai tifotiM of Ihc Earth. St t
<f)ied by the sun and stars, is everj instant varying, cannot p6«sfUy
be denied by those who admit its annaal ahd dfarnid revaldtionVbut
it is equally certain that the centniugal forte depe^ndcnt on tfaii
velocity, is at all times so eqiially compensated by the joint rifanlt
of two coiK^tant attractive forrt s. differently combined, ibal no iii^
dications of its variation can possibly be exhibited in apy cen^ibR
phenomena. The centrifugal forre of each> pafticle of the ^a/tfi
produced by its revolution rcivvf\ the sun, is precisely counter-
acted by the sun's mean attracuon ;'*lhe cep;trifuga1 fbeee derived
frora its rotation round the earth's axis, v^ c6tfnteracted by i
certain constant portioii of the force of gravitation ; and honir*
«v(Br these motions may agree or disagree In direction, their inter*
ference will not prevent the perfect validity of the coifipensationSy
which will be singularly combined. At noon, th6 two centfru
fjigal forces act in coatrary directions, and the centrifugal force^
^ependinjg on the annual revolution is subtracted frbnrtbat wbichr
l>elongs to the diarnaU &nd on the other hand, the solar' attrae^*
tion now acts in a^cection contrary to that of the gravitation
^towards the earth. At midnight the two centrifogat forces are
'United, and so 'are the aittractions. ^nd. thi^ would be eqoall/,
(true if one of jthe motions were directed froti^ £^ai$t to West* and!'
iiot both of them from West to' East. It is unnecessary to con-
iirm this obvious explanation by any abstruse calculations : but
for a single e^cample we will take a satellite i^evolvii^g rotiod 9^
|>lanet with a velocity equal to half of that of the planet in its-
fiTb'xij and at one fourth of the distande ; the attractive fdrt^*"
must then be equal, since the fprte is as the square of t%e ve!t>«
4:ity divided by the radius: at the conjunction of^ th^ sun and '
/satellite therefore, the attractions completely' balance each other^
consequently the joint centrifbgal forces ought to disappear ; but
the velocity is only reduced to pne half ; the curvature therefbrci
n^ust vanish ; and we shall find from the properties oftfae epitro*
.cboid, that the distance of the centre of curvature does actually,
iq this caaie, becon^e iniinite. See Dr. Young's Essay on cy-
.cloidal curves. Prop. 4. Nat. Phil. II. 559. Av\A a similar de»
moDstratio]^ might easily be extended to all possible cases.
These circuits tances were certainly of sufficiisdt importancir
if> have deserved the consideration o( any prf)fmof',\fBioTB lur^
jSu^bmitted l;^i,s new theory to the learned in the mat]{;iematical an^
physical sciences, and solicited their opi^iion (may we not s^y *
xfieir condemnation?) of his hypothesis. And were they not dl$^
sufHcient, to have induced the learned editor of the Philosophicail
Journal, to pause before he &ullied the fair reputation of his Vork^
hy the insertion of such crude and absurd theories.
It ought likewise to be remarked, that if Mr, W/s coticlusioo
relative to the different velocities of any point, of' the equator
^i f^oon ai>d jmidnight could be admitted, he appears to be eqqally
Jitf MnEdgoporth at^ TikgrMphic CommunkaHonM.
^forttt&ate in bis application of it, to the explanation of Aerolithi*
jf>r falling stones. Many instances might be produced, to whicH
)iis (beorj seems totally inapplicable; but we sball meptioi^
poly opfi ; Qn the 13tb of December, 17^5, a large stone^
Weighing 56ilb, felt ^eai ^Vold Cottage^ Yorksbirj^* The three
prinripal volcanoes ra £|irppe^ ^re £ipft, Vesuvius, and Hecla;
the ^irect distance between the place where the stone fell and
ihe last of these, is abo^t £|00 miles; between this place and
Vesuvius ^Iniost 1200; %nd between it and Mount Etna, near
)d.50 miles. The difference of longitude between Wold Cottage
•od Hecla is about 19 degrees ; biptween h and Etna more than
J 6^ ; and between th^ pla^e of iU lall apd Vesuvius near IS
degrees. t^oul^ these distances b^ reconclledi Vith Professor
food's theory, even if ^1 the places lay on the 'same parallel
of latitude } If the stone were supposed to be p^rojected. from onc^
of the Tolc^ic mountains in Aoierica, the hypothesi^ would be
«till more uutenab}e*
On Telegraphic Communications* By Richaii]> Lovell Ebgx-
vroxTH^ Esq.-^PhiL Jaiim. No, 118.
At. the coipmeiicement of this letter Mr. Edgeworth refers to
^D essay of his on t^e subjec^, published in the Transactions of
^e ]^o.)al Iri^h Acadeii^y, at the ^o^clusion of which he ventures
1^, predict ttie futqre universality of telegrapbic communication,!
" whenper arts and sciences have civilized mankind.'* He thctf
Observes/ that among the various inventions for facilftatihg thi^
tcode of conveying intelligence he has seen one ideuOminated ^
]M>mocraph (see our present volume, page 4^) invented by Lieu,
tenaor Sprat^ ;^ and states that \i^ )iad actually practised a si*
ixiilar contrivance Jwelye or thirteen years since. This state-
ment he affirms is not made with a view of derogating from the
inerit of that gallan^ biiicer who is the author of the method
aibove referred to, but with a desire to give bim the advantage
of what much experience had taught Mr. E. and of which £•
li^ drawn up a particular aipcouut for the purpose of recommend-^
iog tpe practice of it to ^e army. ' From the circumstance of
IijB^t^Ift ^fT^it having pointed out the convenience of a dark
object hebin<] the man that makes the signals, it appears that he
hadconfine<^ his method to' a single post, f^qm xht place whence it
iqconveyed;liutMr»|J. renqarks, thai the intelUjence may be con-»
'veyed to any distance by men only, an4 without any other ap^
•aratus than a telescope; and that consequently there is not anjr
bpundsto this mode of communication but the ocean. For thiii
purpose, however, the signal man must be visible fr^m botli(
t^ijore s^' behind. In Mr. Spratt's arrangement there is asi^*
Mr. Edgewori\ 4m l^kgraphtc Commmicathns. 91^
^ai to^sTgniiy that the operator is understood ; but Mn £dg«?
^orth conceives that this is best ascertained by a repetition of
^he sign4l received ; as this in a long tiipe of comoiiuiication will
pot occasion any d«lay except at the second station. Mr^ £dge>-
worth ^also remarks, that either andrograph or. homwtcribe would
)iave been a mofe proper nam^ for this contrivance than .that oS
hamo^aph \ and concludes^ with the following observation : ^^ that
if generals of largp armies would employ the resources of ait
as well as those of mere physical force, they would s^€ much
-iinie an|) blood; they ijpoald avoid much disappointment and
disgrace ; and whether they ultimately failed, or succeeded^ thegr
would hitve the satisfaction of knowing, that (hey bad laegleeted.
90 reasonable means, of ensuring success."
Observations^ — However similar these two metbojs of convey? >
ipg intelligeqc^, invented by Mr. Edgeworth ^nd Mr. Spratt,
j^ay be, ther^ c^i> ]it no dqubt that they originated altogether
indep€ndei)t]y of ea^h other]; aqd consequently ths^t each author
is entitled to the Qierit of invention. 3ui we conceive that it if
i)ot he who first conceives the idea of an invention, but he who
first carries that idea into practic^, ^nd coinmpnicatei his succesii
to others, that has the greatest claim to public approbation, anc]
our readers wil) not hesitate (o allow Mr. Spratt t^bis kind of
priority. At the same time, as there is no reason for doubtii^
the truth of I^lr. Edgeworth's assef tion relative to the priority
qi the inventioQ, there can be v po just reaspn (or withboldin|^
from him *his due proportion of meiit on this account; an4 '
bpth the ^V^nsi^n of the distance to which intelligence may b«
conveyed by ibis method, apd the repetition of the signal received
.ipstead of a separate one being made to denote its being under-r ,
stood, as pointed out by li'lr. £• are certainly in^provements 'on
the method communicated to the public through thfs medium o^
tjie Society of Arts, by Mr. Spratt.
warn
wmnamm
J. Observations on^ Dr. BosxqcK's Remarks upcm Meteorology^
By LvKB HpWARD, Esq,'^PhiL Journ. No. H8. ^ , ,
^, On Meteorological Nomenclature^ in anrmr to Li>ki Howaub,
]^ % J. BosTJocK, ikf. £J.--J6id, No. U9.
3 .— ^1k the first of' these papers^ Mr. Howard appears to have
jB^ double object in • view; viz. to defend his nomenclature an^
system against the objections offered by Dr. Bostock, and tq
offer some remarks, relative to tht inaccuracy of the terms use4
by Dr. B« in his Meteorological Journal. Dr. B.'s observation, to
Wtiich Mr. H. principally replies is tbis^ '* I am not unavrare^
514 Remarks OH Mftrorohgy.
tbftt a scientific Domenclature for the appearance of clouds has
been attempted by Mr, Howard, but I hope f shall net be accused
of presumption, if I give it as my opinion, that his set of names
is much too confined, to be of any use, and that the hypothesis
on which he proceeds, is not entirely correct." The noiAencla-
t«re to which this sentence refers, imposes names on seven
iliodificatifons of clouds only, (seepage \$7ofcut present volttme) :
bat these Mr. Howard remaiics are so many genera, some of
which. comprehend several species, running'* through gradations
so deUcate, and combinations so varied, that the leisure of a Ipng
life might nofe more than suffice, accurately to observe and
describe Shem/' He also adds, that he has not seen any reason
since 1804, either to augment or diminish the number of these
modifications : not that he deems the system perfect, but because
h answers the intended purpose. He likewise thinks a multipli-
cation of terms in the present «tate of meteorological science not
at all desirable. With respect to the erroneous hypothesis alluded
to by Dr, B. it is titated to be that of Dr. Daltbn on the constitu-
tion of the atmosphere, to which Mr. H. had recourse, in illustrat-
ing his speculations : and he now refers to the article cloud in
Dr. Rees's Cyclopiedia, where the natural history is given indc^
pendent of hypothesis.
Mr* Howard ne:xt offers some observations on the terms em-
ployed by JJr.'libstock, to denote the different appearances of the
ibloucls, ' the motion of the wind, ^c. and at the same time
^sw€rs' some objections to his system, urged by Dr. B. in the
'Annual Review for 1 804. To most of these terms he objects,
'as being either imperfect or inaccurate ; but as he examines
.each of them singly, and also discusses some facts to which they
'relate, the particulars would exceed the limits we can allow the
present article, and we must, thereforeji refer our curious meteoro*,
logical readers to the paper itself for these objections.
2.— Dr. Bostock first expresses his surprise at Mr. Howard's
strictures on his meteorological observations ; and then observes,
that he had long been in the habit of making meteorological
observations when Mr. Howard's Essay on that subject appeared^,
amd that the first impression it nnia(][^ "P^^^ ^^^ mind was very
favourable, as many of the terms appeared tg be both charac*
teristic and judicious. TH«se terms he employ/ed in his own diarv,
Svith both the desire and expectation of finding thimn materially
ueeful ; but he states, that he found them on triol tq be inador
quate to the expression of the di^erent atmospherical appearances^
which he thought of sufficient importance to berecoixled; ao^
^herefort, after some time he discontinued their use. Whether
the defect was really in the nomenclature, or in his uoskilfulness
in its use, he does not attempt to decide ; but thinks that the only
efiectual method of evincing its minuteness and potnnrthepsioiiy
s Aemarks an Meieorotogt/, iill
V^^ilt be for Mr» Howard to produce a specimen of a diary con-
strue ted after the manner of his ; or so as to afford a couiplctcf
history of the atoiospherical phenomena of each day ; and avowt
his confidence)' that Mr. H. vrill readily admit tke utility of saoll
a series of observation^. With a view of shewing that he is not
influenced by any selfish desire of making way for his own peculiar
opinions at the expense of others, Dr. B. asserts his readiness ta
enter into any plan of co-operation, which may appear to afiford
the greatest fecility in the execution of his project.
•aUttm'^^i^
Observations .-^Iti the study of the variable phenomena of the'
atmosphere, and the art of deducing probable conjectures relative
to the future state of the weather, we conceive that great attentiont
should be paid to the strength and direction of the winds; to the'
variations in atmospheric gravity or pressure ; to the degree of
its temperature, and the changes which it undergoes ; to the state
of electricity which it exhibits ; to the degree of moisture which
it contains; and to the visible and various phenomena that are
supposed to depend upon, and to result from these circonistances^''
either separate or in a combined state of operation. The ability
of foretelling the future state of the weather, which the plough*
man, the mariner, and the fisherman have attained by experience
alone, we are inclined to regard as a very favourable indication^'
of what may be dope by the assistance of philosophical instru-
ments. It is by means of these,. that the causes, from which the
variations in the visible phenomena of the atmosphere arise^ *
must be traced ; and the greater the variety, both of the observa-.
tions and of the places where they &re made, the greater will be
the real progress of the science of meteorology, arising from a'
cafreful comparison of the results. In order to ensure the utmost
facility, acciiracy, and extent to this progress, a co-operation of'
all those gentlemen, who may have inclination and opportunities
for making observations and experiments of this nature, is cer. '
%^inly desirable, if not absolutely necessary. Instead, therefore,
of meteorologists entering into discussions of a controversial aad*
personal nature, and often exhibiting specimens of that angryr
discordance visible in the element which constitutes the object-
of their study, we should be glad to perceive that harmonic order
pei;vading ail their labours, which the results of their researches
must ultimately obtain, before they can be admitted as the con-
:ted and 'connecting links in the chain of mete orologic<\l science'r
t 3t6 )
k
lemarki oh Mr. Richaud WaIkeiC's propmed Alterationf in iht
Sc4iie$ of Thtrmamcters. By Lo n Dt n en « is. — PhU. Mag. No. 1 4f .
The author of this article tliinks that the various improve-
tnents and suggested reforms in the weights^ m^asures^ and modes
iif e^tinfating quantities, in hoth this and other countries, hav«
been chiefly neglected on accoiint of their authors not having
assigned *' new and appropriate names and characters to the new
<fenuminations or things, which it was their object to introduce ;*'
but instead of this, they (lave generally applied the old names to»,
things very difterent from those which they had been previously
used to designate. It is conceived thdt, if the most precise c«m*
pou\d words in the Greek ot Latin languages, indicating the diffe-
rent degrees of heat, were used as new affixes to the number oH
thermometric di'visrons proposed, instead of eithei" the word
degrees of th^ characiet ° in use at present, the alteration pro-
posed by Mt-^ Walker wi^iild, perhaps, te adopted by many. A$
distinctive characters for the diflerent (fegrees, the initial Greek
letters by which they are denoted, mij^ht answer t^e purpose.
** Negative signs would thus become unnecessary, and no confu-
sion could arise frc^m their iise; while oh the otber hand, every
true friend of science and accuracy, witi naturally adhere to the
divisions in t/^e, At answering their intended ends, although not in
the best or moSt perfect manner ; and set their (his) face against
imperfectly contrived changes/' This writer also thinks that a
material (ircumstabce in. the use of mercurial and spirit
fherm6meters has been omitted by Mr. W. viz. the difi'eien^
periods of time necessary for each to acquire and indicate the
temperature of aby medium under experiment.
Ohservationk.'^Tbr a description of Mr. Walker's proposec|
alteration in the scale of thermometers, we miist refer to page
^7 of this volum<f. We canilol lielp thinking the plati suggested
by Londinen^is toO op^roSe and intricate, eiihei' fur v^egance or
for utility.
Note^f relative to a method <^' constructiitg icooden Bridgis* Bjr
M. WiEBEKiNG. — PhiL Mag. No. 148.
M. Wlebeking, director of roads and bridges to the king of
Bavaria^ has discovered' a mi&thod of constructing wo(klen' bridges,'
trfaich in point of strength and solidity, promise a duration or
teveral centuries. They are also remarkable fot the elegance of
thmr iorm^ and the width of the arches. A bridjje has btten cojk*
Note respecting the CoriMtructum. of Wooden Bridges. ZVf
siructed on the above plan over the river Roth, five leagues from
Passaii, consisting of a single arch t^vo hundred feet, wide;
another has been made for a large city, two hundred and eighty*,
six feet wide. These arches naay be so constructed, as to «diiiit of
ships df war or merchant vessels passing through them, an apei'*
, tyre being made la the centre, which can be opened' and shut at
pleasure. Another advantage possessed by these bridges, is that
of being speedily taken to pieces, if it be necessary to stop the
progress ofan-enemy ; the arch may be rwnoved in one day. and
the abutments «in. another^ without cutting the smallest pieca
of timber.
With respect tt) the advantages in ecomuny resulting frdm tb«
adoption of M. Wiebeking s plan, it has been estimated that a
stone bridge of similar dimensions to a wooden onn of a given size
would eost two millions of florins, whereas the latter would cost
only 50,000 florins; and on the supposition that a wooden
bridge will only last 100 years, it foUows that, taking the interest
on the .principal sum: into the. computation, there will result ^
saving of eleven millions six hundred and eighty thousand florins/^
Obt^roettwHSn'-^li the, circumstances recorded in ^^^ ^^^ ^^
correct, tfai^re can be no doubt of the iihportance of Mr. Wiebe**^
king's invention : and particularly in many places on the con-
tinent, where wood is -^ comparatively cheap. But as we ar^ not
furnished; with auy description of his method* we cannot form
any opinion relative to the stability of its principles.
On Pendttlams. By Ez. Walkek, Esq. — PhiL Mag. No. 148.
INI II. Walker observes ;that, whether any real improvements
have been made in the inec|ianism of pendulums since the days of
Harrison, is a question on which there are a variety of opinions.
With a view of reducing, th^ gridiron pendulum to a more simple
form, rods of the softer met^l^^have been substituted for those of -
brass ; but experience has proved that ihey do not long retain the
same power of expansion and contraction under the pressure of
the lens. MV. W. also states, that Mr. James Bullock told him/
that brass and steel were the only metals, that he could depend
upon in the construclioq of compound pendulums. The construe*
tion 4»f the; gridiron pendulum is founded upon the supposition
that its length is preserved invariable by rods of ditferent pnetals,
which have their lengths djaly proportioned to their powers of
expansion and contraction. But several objections hav^ of latt
heen urged against this mode of compensation.^ " The principal,
of these objections are.: 1st, The length of the pendulum may be
X increased by its weight; 2^4^ Where the rods* pass through tbtf
^jNo. 25.-rVoL. VI. 'ST
9 IS • tAfr. Ei. Walker on PendMtwm.
connecting bare there is some friction, which caas«0 them to
inbve by starts, and not according to the increase and decrease of
heat ; and 3dly, The difficulty of exactly adjusting the lengths
of the rods. But there is another source of error in this pen«
dulom, which has not, I believe, been attended to by writers on
th\i subject." This source Mr. \V. states to arise from the tno**
tions of ihe cross bars altering the distance between the centres
of suspension and oscillation, unless the weights of these bars he
adjusted to their motions. * ,
- Mr, \V. then employs the method of fluxions in investigating the
proportional weights of these cross pieces, in order that the dis^
tance between thp point of suspension and the centre of gravity
of the pendulum may remain the same at all ten^peratuits ; and
concludes that, ^^ if the weights of the crosa pieces be inversely
as their motions, they wilt not alter the distance of the point of
suspension from the' centre of gravity." An attention to this
particnlar, he thinks, would improve, but not perfect the gridiron
pendulum; and therefore he conceivesjthat a pendulum of a more
Simple construction, and more easily-adJMStable to different degrees
of heat and cold, is still a fiesirable object with the astronomer.
^ The mevcurial pendulani," he asserts, ** is founded upon prin-
ciples more simple' ai^l correct than *any other compound pen-
dulum that has yjtt been invented." ^.Tihe objections to which it
^as liable on account of. its glass rodj are now obviated by the'
substitution of a steel rod, with a^gUun vessel contadning quick-
silver attached to it ; -.so 4^hat when the vod expands- dowutv^rds,
the quicksilver expands in a contrary direction, and vice versa.
The compensation is to be adjusted by the quantity of quicksilver
in the tube ; and which, is consequently to .be increased or di'
mmisbed accordingly.
This communication is accompanied with a register of the
going of a clock with a' pendulum of thisltind, from the 27 ih of
June, 1809, to the 12th of July, 1810 ; from this table it appears
t))at the greatest daily variation m the rate of going of the clock
s^dom exceeded one second, and^then only by one or two tenths.
TThe rate of going was computed from the son's transits over the
meridian, observed by a transit telescope of 3| feet in length.
' ' Oft/^rTflf/ow.— Most of our readers, we suppose, are aware that
the gridiron pendulum was the invention of that very ingenious
artist, Mr. John Harrison, celebrated for his invention of a
V^atch for finding the longitude at sea, about the year 1 7^5 : and
that it consists of five rods' of steel and four of brass, placed iq
alternate order; the middle rod, by which the pendulum is sus-
pended, being made of steel. Simple and ingenious;as the con-
struction of this pendulum w^ at the time of its invention, we
think that other objections might be urged against it; beside
e'
Jl/r. £z« Walker on fmdulum* 319
those mentioned by Mr. Walker. Tbe chief of these are the
difficulty of proportioning the thickness of the rods, so that they
may all. hegin to expand or contract at the same instant ; and
tlie gieat resistance which it receives from the air.
The mercurial pendulum^ to which Mr. Walker gives the pre-
ference of all others, was invented by the ingenious Mr. Graham,
about t^e year 1715 ; and there ai*e doubtless many strong proofs
of its practical excellence. We conceive the most forcible objec-
tion that has been brought against it is, that the expansion of the
mercury commences sooner than that of the glass rod : and for
this there is certainly not any remedy provided by attaching the
glass tube to a steel rod, as mentioned by Mr. W. We should
certainly be glad to record -Mr. Walker's invention of such a
pendulum as be thinks so desirable an object to astronomers ;
while at the same time we may be permitted observe, that we.
hope it will shortly fall within our province to notice one from
a different quarter, which has been both invented and .tried for a
considerable period ; and in which both simplicity and accuracy,
!are united in a very high degree.
As we are desirous of making our work the channel of as much,
practical Infonnatiou as possible, it may not be amiss to notice
tjie following excellent mode of effecting a compensation, which
we conceive has not been so much practised as it deserves. It
is described by M. Thiout, a French writer on clock*making ;
and was used by an ingenious artist in the north of Englaiid,
about forty years ago. A bar of the same cqetal and dimensions
as thi^t which constitutes the rpd of the pendulum is fixed to the
back of the clock-case. . From the upper end of this bar a part
prqjects, to which the upper part of the pendulum is connected
py tiyo fine pliable chains or silken strings, which just below
pass between two plates of brasS) the lower edges of which will
always t^ern{)inE|.te the length of the pendulum at its upper extre-
mity. These pls^tes are supported on a pedestal fix^d to the back,
pf tl^e plQck-case. The bar rest^ upon a moveable base at the
lo\yer e^d^ ^^ is inserted in a groove ; by this means it always
retaii^s the same position. Fnim this construction it is evident,
tbi^t ^he exipan^ion or contraction of tbe bar and the pendulum
rod will be ^qual, but in contrary directions. For supposing the
rod to b^ txpii^nded any given quantity, then as the lower end of
the bar rests ^pon a &xed point, it will be extended upwards,
and raise the pendulum just as much as its length was iacrease^
by tbe additional temperature; and consequently its length.
below tbe plates will be the same as before.
It must not, however, be understood that the bar ^d the pedes*
tM^ aie tQ be fixed to the back of a common clock-case of wood,
since this would be merely 1^ substitute the variation of the wood
ioT that Qf the metal, aud since all wood is liable to great varia*.
920 Mr. Ez. IValker on PendiUims.
tton in ito dimensions from moisture ; but the apparatus must be
fixed by meaoK of stone work, or of some other siibstanlre little
liable to expansion : and in the arrangement described by Dr.
Fordycc, Ph. Tran». 1 794, even the expunsioti of the stone is
compensated by making the 6xed bar a little longer than tlie
pendulum. '
■ ■ I ■'■'' "ii
« ' •
Expenments on the comparative pawert of Cylinder and Plate
' Electrical Machines y and an a mtons of doubling, trebling, qua^
' drupling their chargivg poxjoer^ ^ -A/r. John Cuthbkhthon,
and Mn G. J. Singe it. Contmunicated by Mr, Singer.—
Phil.Joum. No, 118.
• Mr. Singer stales that the opinion pf electricians has been
ninch divided respecting th^ best form of an electrical machine.
Globes, spheroids, cylinders and plates have been alternately enu
ployed and recommended by different Experimenters. Only very
slight effectiB were formerly produced; and " the much im-
proved construction of the cylinder machine by Mr. Nairne,/
the experiments on electrical excitation by Mr. Nicholson, and
t!ie structure of the unrivalled Harlem apparatus by Mr. Cuth-
bertson, are the circumstances that have most enlightened this
subject." The influence which apparently slight causes have
upon results in experiments of this kind render it necessary, in
order to obtain any accurate companson, that the two instru-
ments should be used at the same time, in. the same place, and
under' similar circumstances; and these were particularly at-
tended to in these experiments.
" The instruments employed for comparison w»erc a cylinder
of T4 inches diameter (with a multiplying wheel, and pulley,
the proportionate diameters of which were as four to one), and a
single plate machine of 24 inches diameter, turned by a single
winch, as usual. The management and excitation of each ma*
cliine were undertaken by the individual who had constructed it,
and an equal advantage was thus afforded to both. To insure
greater accuracy, the results noted were in all cases the mean
result of repeated experiments : without this precaution, tbe
sources of anomaly would be much more frequent and numerous.'^
These experimenters consider tbe gradual increase of charge
conveyed to a known pleasure of coated surface, and the liision
oif certain quantities of wire, as tbe best test of electrieal action ;
but in the course of their experiments ti>ey bad recourse to every
known means of ascertaining comparative quantities. In the first
part of this series of experiment many ditliculties were encoun-
tered; but aft«fr these were surmounted, the mean result of near a
hundred trials, tended to prove that the charging power of the
two machines was precisely equaU ...
y^
/
* *
Comparative Expmments vn electrical MacMnes. 3^1
In the first of the experiments cited here, a battery ©f 15
jars, expoeiilg aboat 17 square feet of coated surfare, was charged
by the cylinders with Cuthbertson's electrometer placed at 13
grains : the charge was effected by ISO turns of the wheel,
and 48 inches of iron wire 1- 100th of an inch in diamelttf*,
ifi ere rendered red-hot and fused into balls. With the same ar-
rangement, the same effect was produced by 138 turns of the
plate. And ii^hen the two instruments were used together to
produce the charge, the same effect was obtained by 6*5 turns of
each. This is just half the ft umber of turns thatt was required
by the most favourable action of one, and aHoixIs a complete *
proof of the similarity of their |>owers. The 48 inches of wire
that was fused in these experiinenls was also found to be a good
measure of the force of the charge eniplqyed : for on repeating
the experiment with 49 inches of the same wire, it was barely
rendered red-hot. The power i^ecessary to put each machine in
motion was next tried by suspending weights from their handiles
in a horizontal position ; and it appeared that the plate required
8lb6. and the cylinder iOlbs. to produce the same change of
position. After some alteration, however, had been made in the
rubber of the C3rlinder, and it had been furnished with new
siik, it was fouiid that its power had been increased by oiie^
third.
After the experiments had proceeded to this point, Mr,
Cuthbertsun discovered a method > of improving the , plate ma*
chine by means of multiplying wheels. A second series of
experiment^ was then iuscituied, which our limits will not per'-
niit us to particularize ; but which are stated to have sufhciently
proved the utility and importance of Mr. Cuthbertson's improve-
roent, bywtikh the original charging power is quadrupled.
Messrs. C. and S. think that this principle is capable of being
carried still farther ; and observe ** it is fair to conclude, that,
by the proper a,pplication of a moving power, the quantity oi
electricity given out by any machine in a determinate time may
be doubled, trebledy quadrupled^ or even increased six or tenfold^
The discovery of this principle is therefore of the highest im-
portance, as it offers the most effectual and ready means of ob-
taining a very considerable accumulation of the electric fluid ;
a circumstance of considerable interest in the present state of
electrical and chemical science. These remarks are succeeded
by statements relative to the comparative advantages of the two
machines, which are as follow :
** The principal advantages in the cylinder are, I st. the posi-
tive and negati-ve powers are obtained in equal perfection ; 2nd.'
it has but one rubber to, keep in order ; 3rdly, it is less liable
from the security of its form to accidental fracture than the
plate; 4thly, its insulation is more perfect; and dthly, from
392 Discwerie* in tie Theory ^ Gamtis^ hf Daerfel ani Hevdius.
the peculiarity of its structure larger multiplying wheels msiy be
iBinployed, {^q4 th^H ^ CQnsiderc^fa^le 4i(uif)uti(m of its friction be'
obtained.
** Th^ advantages of the plate machines are, 1st. they are
Jess e2(pensive than cylinders of equal power ; 2adly, they oc-
cupy less room ; 3rdly, may be constructed of a much larger
size, as instanced by AIr« Cu^hbertson's l^rge niachiue at Har^
km ; 4thly, several plates, to act jointly, may be more easily
fCHxibined, than severa) cy^nders could ; 5tbly, the multiplying
Bower may be applied to tbent to a much greater ej^tent, than
It could to cylinders, without rendering the inotioq too rapid ;
(Sthly, plates of equal diameters n^ay be made to act with a
uniform and to^ degree o( power, ^ ci^uR>sta^c? aeldoot
c^t^^t^K^ec^ b^ cylindiyrs,'* *
Observations, "Tj^^ fully agree with Mr. §i^ger respecting th?
importance of a ready and effectual means of obtaining a consi-
Arable accumulation pf the electric f)uid;| more especially iq
the present state t)f electro-chemical scie^ice, w^^en th^ gepius of
invention is qn the wing, and, though s^he has already soared ^
high, appears • to be hovering only f(>r fre^h powers tq co^iduct
her to further discoveries. The coinclusion$ at which the^e ^x-.
perimenters havf arrived, seem to be warranted by their ex-
periments ; but as Mr. S. observes that ** many experiments
remain to be made, and when a suilicient number of thest
kave been completed, 1 shall not delay the communication of
them to the public/' we shall not protract our rf marks i^t
present.
>
On the Discoveries ichich Daerfel and Hsvstius, made m the
Theory of Comets. By J. C. BuaCKiiAHBT.«-C9it«atMafice c/ei;
Terns for 1810.
Daerfel, rector of Plauen in Saxony, published a smal)
work on the comet of 1680, which is very scarce ; and it has
been asserted that Daerfel was acquainted with the true para,
bolic motion of comets before Newton* The late M. Lalando
requested an explanation of this subject in Zach*s Journal, but
he did not receive an answer. Delisle is said to have procured
a manuscript copy of this work, and made a Latin translation
of it.
The Cometogr^phy of H^velius is not so scarce, and has b«en
employed and cited by Daerfel. Besides, Mess. Lalande and
Pring6 differ respecting tiie discoveries of that author. Heve*-
lius took four observations and sought a right line which repre*
seutedthem; this gives him ttie vdocity of the coqaet for the
Dlsbffverle* in tie Theory ofOiJmii^, by Dd^fel and HeViUnB. ' 5^'
tbrce intervals coGtatned bf^ween the four ■ observations ; he iii«
Ibi-s from it the. diurnal motion for every day, by supposing the
variations in the. velocity pr^ppitional to the times, and he com
eludes with comparing this theory with all the observations of
the comet. Hevellus has also applied this method to all the
Gome^ts observe^ at that time, and derives the following results,
1. Comets do not describe a right line, but a curve concave
towai*dt the sun ; this corve he supposes to be a parabola.
2. The veloitity of comets varies, but in a regular manner^
and proportional to the times.
3. The greatest velocity takes place at the perihelion.
4. The velocity is not the same at equal distances before and
after \he. perihelion;
3. The velocities of different comets do not follow any fixed
law.
Hevelius has not demonstrated the motion of comets m a pa-
rabola, liut he has conjectured it 'in a happy manner, and that
eonclusion wa!s the result of great labour. The little agreement
between this hypothesis and observations induced him to imagine
that comets soir(etimes quitted their oi:bits towards the' ei^l of
their courses.
In Daerfel's work, the first section is occupied with liis ob.
tervations on the comet of 1680. In the second section he en-
quires whether" there were two comets or only one, and decides
for the latter.' An elliptic drbit not agreeing with these observa-
Aons, be' tried the parabolic hypothesis which Hevelius, had pub*
V Irsbed in his *C^metography. Daerfel, howpver, employed not
the calculus,' but contented himself with a construction. In
otder to correct and ftetfect the theory of Hevelius, this authcnr
proposed to place the dun in the face of the paral^olas. He states
that Hevelius had not been explicit respecting the place occu-
pied by the focus, but adds that- the preceding comets were not
so favourably situated as thls^ for making the discovery. He'
observes, ** if this discovery be. found true, it will not be difficult'
Upr those who are acquainted with conic sections to indicate me-
tbods of calculation for the theory of comet8> in order to find the
distance from the vertex of the orbit to the solar focus, and con-
sequently the ratio of the diurnal motion in the trajectory, the
distance from the earth, and in certain cases the true distaiicb
from the sun.
In the third section, Daerfel shews, contrary to Kepler; that
comets do not furnish any proof of the ti'Uth of the Copernican
system, declares for that of ^Tycfao, on the authority of the
Hible, and asserts that it was only on account of the facility of
tbe calculus that he adopted the former in what preceded. In the
next section of his work, this author proves that the apparent
zuotioD of the comet was not iu a great circle ; and in that which
^24 Discoveries i^ the TheQrj^ of Sonuis^ by Daerfel andtfevekUs
succoedsy. be »hcw8 how tf> find the horizontal parallax of the*
comet by the variation of its pavallax in altitude, and from v^bicti '
we may conclude that of the sun trhen the comet approaches
bear the earth »
«- From what precedes it appears that Daerfel had made an
important discovery^ in proving that the sun occupied the face
of the parabolas described by comets ; and also that there still
remained anothei' grand step to take, viz. to ^pply the laws oi
Kepler to the parabolic theory of comets.
' Ohscrcaiions,-^-tn this paper, however curious and interesting
as relating to the history of astronomy, it seems to us to be
somewhat too much M. Burckhardt*s object to establish the
priority of Jinowkdge respecting the parabolic theory of comentar/
motion in favour of Hevelius and Daerfel, wt the expenc^ of the
well-earned fame of Xew ton. This nc think is more than either
has been or can be done.. The Cowt7o »t^;7 Aifl , of lie veliui^^
above referred to, was publislied in 1 66*8, and copies of it sent to
Dr. Ilooke and several nembers of the lloyal Society of London;
and Newton was certainry acquainted with it, as he both refer*
to it, and quotes from it in that part of the third book of the
Principia which treats of comets. With Ilevelius and Daerfelj
the parabolic motion of Comets was naerc conj,ecture,'.arising from>
accidental circumstances, rather than weJl*grounded or tiemoH',
strated ktwickclge. Newton seldom stopped at conjectures, and
when he did he proposed them in the. shape (;>£., queries, rather
than aflirmed them as facts. He generally brpught theni to tl^e
test of geomctr}', and either demonstrated their truth,, qr, shewed,
tiiem to be mere suppositions. Respecting comets^ be first sup.-
poses (Principia, lib. iii, lem, 4. cur. 3.) that they are " a sprt of
planets revolving in orbits, .returning into themselves with a per»,
petual uiotibn.*' He then proviis, in Prop. 40, that *Mfcoiaet;5]
revolve in 01 bits returning into themselves, those orbits will be
ellipses ; and tbeir periodic .times be to the periodic times of the.
planeis in the sesquiplicale proportion of their principal axes ;' ;
and still further, that ** . their orbits will be so near to parabolas
(in the parts near the perilielion) that parabolas may be used for
them without error." Hence it is evident that what the roost
illustrious precursors ol Newton only guessed at, he has demon-
strated ; and thus laid the foundation of his fame, even ^in this
respect, on too elevated and permanent a rock to bp eitlier over-*,
shadowed by prejudice or over^hrawh by envy.
( IM )
1, On the Action of the Electric Fluids by which fm IrmCyUndit
afyinch and a half thick vms torn ttsunder: in a Letter ffom
:■ Mr. *** to J. C. Delamei HER-iE.— /jt^iim. de Phyt* vol. 6$^ ,
2. Remarks on the Preceding Experiment. By J. C. DblaHI-^
' 1. Thb author ^)f this letter states that be half filled a ne^.
''lallic cylinder with water. The cylinder was open at one end;
and in this water he immersed a small leaden rod, which was
surrounded wUh iron at the place where it entered the cylinder,
jA order to «(fect ite insulation. He then formed a coummtinica'''
tiOR between one of the surfaces of a pdwprful. electric battery anp
the bottom of the cylinder, and also between tbe leaden rod and
'tile' other surface. The explosions were strong ; the water ofteiv
violently ^ected ;. atid the rod thrown to a considerable disCnnce ;
and after several of these explosions the cylinder was tom* This
vrriter was desirous of trying whether these effects cuuld not ba '
parried still farther^ and he made an iron cylinder 27 French
lines high, and 18 in diameter; with a hole in the centre l£l lines
deep, and 1| in diaraejter. It was subjected to the same experir
Bients as the fdrmer, with a battery which had 100 sqilafe feet
of coated surface*^ and was burst by 70 e.t plosions, 'fbeppening
was w6ll^ cleaned after every discharge with an iron wire^ an(f watet
let fall, into it iti drops, to remove the half fused and oxided grainai.
of lead, and separated by th^ discharge. The c5!linder was then
irefilted witb fresh water, th^ wires placed in the opening, and the
apparatus placed in a box. Henley's electrometer indicated a4
^itensity of 60® or 65° when the discharge was made. It required'
about a quarter of an hour to charge the battery, and about ^Q
discharges could be obtained in a day. The ^tfongest effect wa9
produced when the fluid was 'directed to a single point. And the
«|Bthor asks, can thet ifiterior burning of metals by the passage of
the electrical fluid, which .some (Philosophers have long sinde con?
sifdered as possessing acid properties, now be questioned? lie
also states, ^hat if his experiments be repeated in vacuo with a
• sicnple stream of the fluid, the oxided and fuliginous products '
%viU ,be equally obtained. This writer likewise hints at, the
«iEett of the experiment made in water, but admits that this re*
^ai^s farther examination.
S. Mr. Delametfaerie thinks that the effects of electricity in
tearing masses of so much tenacity as iron cylinders, give soipe
j^robability to the -opinion of those German astronomers who '
jpiave thought that^the four new planets, Ceres, Juno, Pallas, apd
V^sta^ are fragnient^ of a larger planet forme»-ly situated between
•vo* 25«— TOL. YX. 2 ij
i26 Jctknof Electricity on an Iron CytinJkf.
^lan and Jupiter, and rent in pieces by some unknown cadM^«
He supposes that the centre of this planet was a mass of metat
in similar circumstanic/e;^ to the preceding cylindei-s ; and that
either a metallic vein or some otber conducting substance, acted
upon it in the same manner as the leaden rod, and conducted tha
electricity from the atmosphere into the metallic mass : he asks^
might not » great number of such strong discharges as occur m
thunder storfns burst this mass ilnto pieces, aOcT project the diffe-
reat parts to a distance, like tfte snaH. piece of lead in those
valuable experiments ? This ingenious pi^ii^sopher asserts, that
thunder storms must produce effects on the interior of ohf
globe more or less considerable, and refers to kis theory of the
earth, where the subject is treated. He alscv takes occasion to
state the theory of the action of electricity on- the isaf th^; buta»
this theory appears to amount to no more than this viz. that
the equilibrium of the electric fluid may be distwbed by local
circumstances, and that the fluid will the» rush to these points
^hich have been partially deprived of it^ in order to restore the
the e^uilibriunl, we do not conceive that it contains any thing
either sufficiently new or interesting, to induce us to enter iuto^
particulars on the present occasion.
f
Observations. '^Tht experiments on iron cylinders related in the
first part of this article^ afford another striking proof of the va^l-
power of the electric fluid when acting in considerable quantities ^
btit however curious, interesting, and singular, these effects may
appear^ there is another circumstance in the second part still
more so. What we allude to, is the account of the origin and for.
matien of the fouc new planets, as stated by some of the German
astronomers, and supported by the editor of the Journal de
Physique. What real advantages these philosophers propose to
derive from such a supposition \% not very apparent, nor can we:
conceive any motive that could induce them to make it ; for if
it wfere admitted that th« planet vms broken into four pieces,-
there are still a few questions of considerable moment which it
would be neces^sary to resolve. How did these four pieces acquire
their spheroidal form? How did they ^d the ^ way » to tbeir
respective orbits? What impressed upon them their respective
orbital velocities and rotary motions I What proportioned these
motions so exactly to their difierent distances from the suu, and
other local circumstances, as to ensure the stability of their rela-
tive equilibrium in the midst of so many soliciting and disturbing
powers ? How came they to taovt so near to each other, and yet Uy
be so distinct? It is, therefore, much more natural to suppose tha|*
the four new placets, as well as the others, derived their existeixc*
from the time when the whole system was created* . . .^
*Wi4
Tf. r^ .. ( 327 >
Cr ' .
T^fi-authur of 4l!i» eesay ass^rU that two <:onditioDs are neces^
«aT!y» m order to sustain' tbe ring of Saturn in eq«Hlibrio about
%l!(at planet. One of ttiese relates to the equiiibrium of its paits \
^fae other to its Mspension about the planet. With respect to
tbe firitt of these he obserVes, that this equilibrium requires that
the oioledlkB of tho-^tfurfacfeof the ring have no tendency to
dispersion ; and thiat, supposing this surface fluid, it may maintain
its figure in virtue of the different forces bywhii^h it is solicited.
Without this tbe continual effort of the n>decules would end at
■kngtb in separation, and the ring wo^ld be destroyed, like all this
Works of nature >^faich 'have-not in themselves a cause of stability
wifiicient to^resiftt ibe action of ^ contrary forces. He also states
that he Imt proved, 4k ^he third bot^Ex^f the Meeaniijue C^leste^
rtbat this condition can only i>eful^Hed hy a rapid rotary motion
t!^ the ring in itgiplafte and about its centre, always near that
of the pynet. ' 4le iias likewise shown that a section .af the ring
\rf a plane per^iendil^ilar to its plane and paseing through its
centre, is an ellipse lengthened towards that |>oint.
^idi respect to the second condition^ if is observed that a
liollow sphere, and generally a>boHow ellipsoid, the exterior and
interior surfaces of whieh are «imilar and concentric, would be
In equtlibrio about Saturn^ whatever point of the concavity was
4ic<:upied by the centm of tbe planet ; but this equilibrium would
%e vei^ettnty that is, that being disturbed, it would neither tend
to resume its primitive » state nor depart ^rther from it; the
^slightest cause, such as the action of a satellite or of a comet,
vrould' therefore beaofficient to <precipitaie the ellipsoid upon the
planet; The indrfferent equilibrium which takes place for a
lioUow. sphere enveloping Saturn, would not exi&t for a circulav
jBone surrounding that planet; It has been shown i^ the book
above referred to, that,' if the 'centre of the circular «ing do not
Coincide witb that of the planet, they will repel «ach other, and
the ring will terminate by falling upon the body of Saturn* Tha
^a'me thing would happen whatever, were ^ht eouatitotion of the
Hng, if it had no rotary motion \ btft if we conceive that it ia
^lot similar in all its points, so that its centre of gravity does not
coincide with that of its figure ; if we further suppose that it may
4t>e endowed with a rapid rotary motion in its plane, then its cen*
4,re of gravity would revolve about that of Saturn^ and gravitata
Cowards that point like a satellite, with this difference, that it
^^oiyild always Oj^ve in the interior of the |>lanet \ it would tbe/rcj.
y
328 JLapiace on tie Sing of Saium*
ioTtf have a stable state of inotibn. Thus both these ce»«
ditions concur in showing that the ring has a rapid revoking
motion in its plane and about its own centre. The time of itft
rotation ought to be nearly that of the revolution of a satellite
revolving about Saturn, at the same distance with the ring, and
ibis duration is abefut ten hours- and a half* - Dr. Herschel ha*
confirmed this result by his observations ; bnt hoW' are these
^observations and this theory to be reconciled' 'irith the observa-
tions of M. Schroeter, in which some points of the ring iwire
luminous than the rest seemed to remain a long time stationary?
X^aplace thinks that this may be accomplished ia the fellowiii]^
manner : , • u
. • The ring of Saturn is composed of many cancentric rings $
powerful telescopes render two of them distinctly visible^ wiiiefa
iprradiation confounds into one with weak telescopes. •• Ilk is'«very
probable that each of .these rings is itself (CompDsed' of many
9thers« «o that the ring of ^aturn may be regarded at- an aasem-
l^lage of divers concentric rings; such would be the whole 9i
the orbits of Jupiter's saielliteSy if each left in its srack a perm»p
sent light ; the partial rings onght to be like these •rhita^ differ
rently inelined to the equator of . the planet : and then -their iB**
cliaiitions and the position of their nodes would change in periods
of greater or less length, which embrace many years ; their cen*
tres ought likewise t6 oscillkte about that of Saturn ; all these
circumstances would cause the apparent figure of the whole > ring
to vary. • Their rotary motion ^ill not sensibly change that
£gure, since it. only replaces one luniinons part by another
i^ituated in the same place.- It 4s very probable that the pheno*
mena observed by M« Schroeter were owing to variations of this
kind, Ellt, if a point more or less luminous than the others^
§dhere to the surface of one of the partial rings^ it ought to move
as rapidly as the ring, and to appear to> change its position in 0,
few hours. It may be believed with great probability, that it
was a point of this kind that Dr. Herschel observed ; and La*
place eiurnestly requests those astronomers who are furnished with
powerful telescopes to turn their attention* to this point. Thi
variety .of these appearances greatly puzzled geometer^ and
astronomers before Huygens discovered their cause : the ring at
llrst appeared to Galilee like two small bodies adhering to the
^lobe .€tf Saturn ; and Deseartes, who unhappily wished to ex«
plain all things' on the principles of -to philosophy^ attributed the
atationary appearance of these pretended satellitea to the'circum<*
stance, that Saturn always presented the safne face to the centre
^ his vortex.' It is now known that this conclusion is' contrary
to the laws of universal gravitation, and this reason is sufficient
for rejecting the explanation of Descartes, even if the cause of
these appearance^ were not known. M. Laplace thinks tbaf^
.,..«
^ Laplace on the Ring ^ Saturn* pM
^jie immobility of Saturn's ring is not the least contrary to
%bh grancl Iftw of nature, and he does not doubt that the ulteriof
observations' of astronbrhers fUrhished with powerml telescopes^,
iiill eonfirm the rMttltfir of the theory' cind the observation's of
OOr. Herschd. ' ' ♦. . i.
Observatkmi.^^ln the Memmres de T Acadtnne de Pa? is for the
ywnr 1 7^79* Lapiat^ suggested 'that the -ring of SatUrii might
^tooaist of' several divisions or separate rings ; and how, after a
lapse of nafore than 20 years, during which period, no doubil
!tha subject has ireqftentiy occBj>ted his attention * and tried the
atreng'tb <>f his penetrating genius, he > sfiil retains the same
opinioo und^ some slight modifications. But notwithstanding
'all'the leariiingand ingenui-ty 'vrhfch this hypothesis evinces, w^
think that a< -series- of* accurate observations with the best
telescopes 4s Btill necessary to its confirniation and establishment^
and -we' think-tfaat it maty fairly be inferred that this is also the
authav's vojAniion'' on tbe ifubject, since he has been so earnest
iBdkreetiDg the' ilttentibn of astronomers to this point.' Yet;>
«a every su^^stion^of so distinguished a philosopher as Laplace^
fwheup £»r profenndnefti and extent of research on subjects of this
-nature, ■-■ has * no' rivul- toio^ng \ his 'cotempdraries, deserves ' the
closest attentS^B, ii^e hope aU who have favourable opportunities
ier iBafeiDg the requisite observations will not withhold their
md in deciding the question as far as it. may be practicable.
» I • ■ • "^ : ' . * • t T.' ■ • • , 4 '
Memoir of the Dctermnation of the Obliquitji of the EcUptiCy tohick
' 'results from ancient observaiiotis, £i/ AT. LAPLAef.-^-Consacn
sance des TemSf 1811. •'■■..■ .j
In the introduction to this essay, M. Laplace observes that
though the successive diminution of obliquity of the ecliptic, as
^toodexQ times are approached, may no>)7 be incontestible,^ yet we
always^ee,"\vith extreme interest, the grandinequalities of the sys-
»jteiu of, the VKorVd gradually, developed with time* Po|terity;''.wbic!i
\vill l^ea^le to compare -a long ^eeries of very accurate observations
'With the results of ^theory, will enjoy the sublime spectacle muth
better .than we can, to whom antiquity has only transmitted
observations that are very oflen uncertain. But as these obser*
vationSj submitted tp a sound criiieism, are- able, from the inters
yaJ vfhich ^^arates us from^ tbem> to diffuse great light over
toany important elements of astronomy, they deserve the atten.
tion of genmeXers and astronomers. ' ^
i^. ,Xfae author of this memoir divides it into t\yo parts ; viz, ob«
^xvations anteiior and po.sterior to Our era. In the first of these
e ej( amines the observations of the Chinese and Greeks, priiH*
t
•S^O M. Laplace on the Diminu^Hon of the Obliquity of the EcUpti^f
t,Q the birth of Christ ; and in the last, those of the Chinese^
/Lrabs, and Persians, made since that epo<^h« This necessarily
)eads him into many details, to give a perspicuous account o^
which would occupy much more roam than our limits will allow
jjis to ^issigQ t9 this arjticle ; w.e sh^; thierefore, -chitefly confine
ourselves to the results to which his enquiries have 'conducted
him. M. Laplace has inserted herie, from his Mecaoique Celeste,
volume iii. bpok^ .vi. chap. ]cvi. a formula, by which the obli«.
quity of (he ecliptic for ^ very long time m^y be calculated ; and
as few q( our readers may, perhans, possess either this volume
of theCo;inaiss^nce|des X^i^^^* ^^ the work from whi/ch t2)e formula
is taken^ we shall give it .a place {lere. Ju ^he foUowinig expression
]t denot,es the nuipb.er of >e;ar^ .elapsed between 17 bO and the
given time, and the obliquity in decimal degrees will be e^rpressed
by 26^. 0796—3676^^6 f I— jcos. (t.43<^a446)>-103SC/^.4siu.
j(t 99'^ J 227). Here t === r- J85j0 j(th£t tinn^ between IJbO and the
most ancient observation on Xhis subject thaj;. ca^i he depended'
upon, or 11 00 years before our ^ra), which ^yes the cprreitpond-
ing obliquity of tbe ecliptif equal to :^i$^.516ll .decimal deg^es ;
or 2(r 5V 53^^ common degrees; U is A^c^^Wy to incjrease this
result by about 6^^ because th/e obliquijty of the eclipti.c.in J 7^
was greater by this quantity than that givep by the preceding
formula ; thus 1100 year^ before the Christian ^r^..(he oblii|iiM|f
of the ecliptic ^as £3^ 51^58^^; a result which differs only by
^ 4f^ from that given by the most ancient observations of the
shadow of the gnomon at the two solstices.. A m^re perfe<^
coincidence could not he desired; seeing the uncertainty which ac->
companies observations of this kind, particularly on account
pf the penumbra which renders the shadow ill defined*
Observations prior to our Era*
Pbliqui (y of the . Excea of the
pate. Otwervert. £cliptic by Ob. Obliquity by the fintoyer
Krvaiions. Formulet. tbe sec
^lOOCheou-Kong 23'' 54^ 2^^ ^"^ fil'' SS''^ 2^ 4/^1
360 Pytheas . SS'' 49' 20^^ 23P W 1^ 3/ 13^"
S50 Eratosthenes 23^ 46' SJK-' 23^ 43' t9^' ^
50 Liean-Hiagn 23*» 4^ 39^ 23*» 44' 4".4 V 34".6
Observations tiau oar Era^^
173 ChineseObser.tS^ 41' 33" 23"* 42' 17'' i-44'*^|
461 Tsou-chong 23^ 38/ 62"-3 24^ 39^ 53// —1' 0"r
629 Litchoufoung 23® 40' 4"-l 23'' 38' 17// 1/ 47"
^80 Albategnius . 23** 35' 41" 23^35' 13/' 2S"
J 000 Ebn-Junis . 23^ 34 26" 23^ 34/ 50" —24/^
J279 Cochcou-king 23' 3^ 2"-4 23* 3^' 22".5 — 20'^
f 437 Ulugh Bey , 23^ 31' 48" 23^ 31' 5" ^^
a. Laplace on the Diminution of the Obliquify of the Ecliptic, ^ii
The whole of these observations establish in an incontestibl^
tnanner the successive diminution of the obliquity of the ecliptic :
their agreement with, the formula of th« M4canique Celeste leaves
no room to doubt that this diminution arises solely from the
attraction of the planets one upon another, and upon the sun.
The very small differences which exist between the formulae and
the observations being alternately positive and negative,, do not
indicate any change' to be necessary in the values of the masses
which have "been employed ; these values are such near ap-
proximations, that in oriler to correct them, it will be neces-
sary to attend to the new observations with which a series of
ages may enrich astronomy.
mmtmti
Observationt.'^Whtn the construction of astronomical instru-
ments bad made considerable progress towards its present degree
of perfection, and observers had acquired more skill and accuracy
in using t^eni, the successive diminution of the ecliptic in pro-
pqrtion as modern times are iipproached became incontestably
proved; and then it ^as inferred that this diminution would
continue till the ecliptic coincided with the equator. But the
vast .powers of modern analysis having been snccessfuUy directed
to this object, it has been demonstrated that the variation in
the obliquity of the ediptic is confined within certain limits
which it cannot pass ; and consequently, that the prediction of
the more early astronomers relative to the future coincidence of
the ecliptic and equator can never be- /uliilled. Lagrange,^
vho directed the whole united force of his ingenuity and analy-
tical powers to this point, shews that about ^OOO years .since
this dimmution was nearly at the rate of 3S^^ in a century ;
that it is at present, and will be for four hundred years to come, at
the rate of 56" in 100 years ; and that 2000 years from this
period it will be reduced to 49'' in a century. After the expi.
ration of a very long period, the diminution in the obliquity
vrill change to an increase ; but the variation will never exceed
two degrees. The small differences which appear between the
results obtained from observations and those given by the formula
of Laplace, are to be attributed to errors which have entered
into the former, and >vhich are certainly not more than might
reasonably have been expected, when the time at which , these
were made, and the imperfections of astronomical instruments at
tli09«! periods, are taken into the account.
( iS2 )
V
*' . . . • '■ I
Proposal for cmisiructmg and putting in its place f an Iron Tunnel
under ike Bioer Thames* By Colokel Lsnkon. — Fhzl, Mag..
No. 147. . -
Ix this plan proposed by Colomel Lennoo, jth^ whole tunnel is
to be composed of a number of cast. iron frames fastened together^
by means of exterior and interior flanches .and «crew&. Each o&
these frames is to be t(:n feet long, eighteen feet. wide within, and
tweWe feet high at the side, its top being convex and having
two feet in the middle. The proposed thickness of the metal is
four' inches at th^ bottom and aides, and three inches at the top.
Each frame wiJl therefore >^eigh near forty tons. The flanches
are e^ch to be one foot broad, and four inches thick ; and the.
screws four ipches in.diameter, with half-inch sheet lead in the
joints, or' these may be secured by cement. The two adjoining.
ilanches«t the bottoni are also to be- embraced with damps of
iron, eafh twelve* inc^s )brbad,,^ix inches thick, and two. feet:
high.^ t^^olooel Lennoa.observeS| that if the carriage of pieces
of such ^weight ffom the foundry sEould be found, impracticable,;
the sides, top, and bottoni might ,be cast in separate pieces,'
with flanches to join them together ;' these joints may also be.
89 . disposed that no two •f them should coincide. Tubes of
a)M>ut eight inches diameter are to be placed in the interior angle
at the bottom, with proper openings to receive the leakage water,
which will thu6 be conveyed to one end to b^ pumped out*
The d€i>tb of. the river at low. water being only about 30 feet,
19 not Sufficient to Admit of such a tunnel being laid npon the
botton) without obstructing the cdutfte of the stream or interfer-
iug with the navigation of the river ; the first step towards ac.
compUshing this object, would be to excavate the bed of the
.river entirely across to about l6 feet deep, and between 60 and-
SO feet in width, and. to render the body of this excavation as
level and even as possible/ This being doife for the space of
I^QQ feet or rather more ; the next thing to be d6ne is to screw
80 of Abe iron frames constructed according tp th^ preceding.
)Uau together ; and this '* shovid be performed on the bank of
t)ie river rather below the level of low water, in a situation
where the tide may have free access to it."
"If then the ends of these 80 tunnel frames so foined be
(when empty) close stopped with strong oak plank, and yf.eW se-
cured so as to render them perfectly water-tight, a machine is
Jbrthed which on the admissioft of the tide vMl float ; as may be
S roved by the subjoined calculation, wLich for greater security .
oes not include the covering at top. At spring, tide, therefore,,
tbe whole may be floated to the rec[uired situation, and b^^ addi*
r
CoL lJtnn6n*s Propasdlfor an Iritn Turinet under the jC^m^f* SSS
tmnal weights applied sunk in its proper place. But in case of
any irregularity in its descent, or unevenness of the bottom pre-
pared to receive it, bj^ removing those additional weights it will
again become buoyant, when the necessary remedies may be ap-
plied and obstacles removed. When once properly placed, by
turning cocks fixed in each end it will soonfiil with water and
be permanently bedded.
Calculation of the weight of this tunnel in round numbers : '
Cast iron . . * 20,020 cubic feet • . about 4,270 tons
Lead . ... 560 178 .
Oak .... 200 ...... . 5
Tons 4,453
Water displaced 1 ,850,000 Cubic feet .... 5,16'2
This tunnel will require to sink it more than • . 709
Exclusive of the convexity at top Estimated at . 60
Total . 769"
Allien this tunoelhas been floated to its destined situation, and
properly se^rured by anchors and cables, which should be done
about an hour before low water, at the lowest tide, the sinking
of it may be effected by means of two short ropes with loops at
each end passed over each frame, and slightly secured to keep
them in their places ;^ and a number of boats on each side with
a sufficient quuntity of ballast so disposed as to adinit of being
immediately hooked on to the ends of ^ese ropes, hi such a manner
that both ends of the tunnel may sink exactly trgtther. The
weights niay be regulated or removed at pleasure as circumstances
may render necessary ; and the whole of the operation performed
in the space of two hours, if all the previous arrangements be
properly made. Or the sinking may be conveniently effected by
letting 800 or 1000 tons of water into the tunnel : having a pro-
per pump"fi.\etl at each extremity to pump out a sufficient quantity
if it should be found requisite to float the tunnel again.
This part of the tunnel is (hen supposed to occupy about 800
feet of the middle of the^ river, and to have its upper surface
rather below the level of the present bed " Then by piling off
the tide from low water- mark, the ends may be completed either
by similar frames or arches of stone or brick work, as may be
deemed most convenient. ** It will then only remain to open a
communication with the middle part^ by removing the oak
planking at each end, and pumping out the water ; when by ^y« *
iog a sufficient qnantity of ballast so as to form a roadway clear
above the lower flanches^ an^ restoring the banks (p thtir fprxne^
No. 25.— VOL. Tl. 2 X
534 ' CoL JjcnnorCs Proposal for an Jron Tunnel under the Thames.
state, the tunnel will be immediately ready 'for use." In tb»
execution of this project, a place should be selected close to losv
water.nlark, of about 300 yards in length, and blocks laid su{i>-
cient to support the whole weight, and upon which the whok
80 frames might be screwed together. This CoL L. asserts
should be at least 15 feet below the level of the spring tides, in
order to secure its floating when finished.
From the vast weight and great length of this tunnel it may
be objected, that the power of 6'7 screws at each joining would
be inadequate to hold the whole perfectly together ; but this Col.
L. endeavours to obviate by the considerations, that it would
neither be subject to any particular force at its launching, nor to
any partial bearing on its bed : and therefore concludes, that the
danger of accident would be small, and the strength of the whole
sufficiently secured. He conceives that the greatest difficulty
woultT be experienced in excavating the bed of the river to the
required depth ; but leaves this subject to more experienced
engin^rs. NVith respect to the expense, he states that the ma-
teriab can be procured for about 44,0001. and estimating all
othei: expences incurred hi the execution, the whole cost would
be about 66,0001. *
If it be desiied to have a foot path besides the space allowed
for two carriages to pass, six feet more width must be allowed^
or the whold made 24 feet between the interior flanches. In
this case however, this writer thinks it would be advisable to
omit the int€frior tlanthes on the sides, and supply their places
with plates of cast iron the whole height of the side, and thre«
or four inches thick, extending from the middle of one frame to
that of the next, and fastened in the same manner as the other
joinings. This would greatly increase the strength of the tunnel^
and allow nearly a foot more free space within, without adding
more than twelve or fifteen thousand pounds to the expense stated
above.
£>"»'
OUercations* — Without entering into a minute discussion of
the practicability of every part of Colonel Lennon's ])roposal, we
,wiU venture- to state, that we apprehend there would be much
, greater difficulty than he seems to imagine, in keeping open the
. whole of the necessary excavation, in a proper state to receive
.the united tube, when completed. The expence too, we believe,
would be incomparably greater than his estimate ; and if an iron
tunnel were ever fixed by any mea,ns, it would probably be ab-
solutely necessary that jts separate pans should be let down
into their places ih succession, as \Vell on account of their being
*mare mana^aWe, as in order that, they might be placed and sup-
"port^d in such a maoneras hot to pfodute* too great a strain on
e^ch other.
Mr. Watktr^s new jnetallk Tkerfh^meter. 355
It seems somewhat extraordinary that this gentleman should
be totally unacquainted with the steps that are now taking by the
Thames Archway Company at Rotherhithe for the execution oi
this project. In the course of last summer that company offered
by advertisement considcral^le premiums for plans on 'this sub-
ject : more than fifty were presented to thera, amongst which
there were many in principle similar to that proposed by Colonel
Lennon, and in our opinion, (for we inspected the whole of them,) ,
several superior to his in the mode of execution.
The result, however, of a very cautious examination of the se*
▼eral plans by those skilful and experienced gentlemen, Doctor
Hutton and Mr. Jessop, was the lecommendation of one whose '
principle was to form certain lengths of Brick Cylinders and sink
these lengths separately in the bed of the river, and to unite
them under water. The excavation in this case, will be made
in short lengths, and precedes but a short time the sinking of
the cylinders, and of course may easily be kept open.
Preparations for this purpose are now going on at Rotherhithe.
Description of a Metallic Thtrmometerfor indicating the k/gher De-
grees of' Tetnperaturc, By Richard Wa lkeji. r—iPA«/. Mag.
No. 148.
Mr. Walk Ell's object in contriving this new thermometer
^as to exhibit the degrees of heat in the intermediate space be*
tween the upper termination of the mercurial thermometer which
ends at 6*00^, and the commencement of Wedgwood's thermometer,
the scales of which begins at red heat, or 1077 ** of Tahrenheit ;
and thus to form a connection between the two. The princi-
ple of this invention Mr. W. describes in the following terms :
*' A metallic composition is formed, not fiable to alteration in
its quality or quantity by repeated exposure to heat, the melting
point of which id a little below 600^ of Fahrenheit^ and its
boiling point at 1200^. A case resembling in form the glass
case for the ordinary thermometer, but somewhat larger, cbntains
the metallic composition, and the scale consists in a slender
graduated rod^ equal in height at the commencement of the scale^
that is, when the metallic composition is just liquid to' the top
of the tube ; the graduated rod terminating at the bottom in a
thin circular, flat plate, which rests or floats as it were upon the
liquid metal, and in proportion as the latter expands and rises
in" the tube by heat, the graduated rod is buoyed up, or raised
above the top of the tube, passing through a perforated cover
to the maximum, or boiling point." Both the case wh^ch
contains th^ metal, and the graduated rod, are at present made of
4)ipe-clay, previously prepared by being exposed to a sufficient
536 Mr, Walker's nHo metallic Thermometer.
degree of heat; and the scale of Mf« W/s thermometer
is a continuation of the scaic of the mercurial tbermoineter.
Mr. W. aho thinks that the same principle is capable of being
extended to xanswer for the most intense heat that can be re-
quired. The influence of the incumbent atmosphere upon the
liquid metal within the open tube, he thinks, is too inconsideTable
at the commencement of the scale to deserve notice, and will di-
minish to nothing at high temperatures ; especially if the whole
of the liquid in the thermometer be wholly, immersed in that of
which it is required to indicate the temperature, which should
always be the same case.
Mr. Walker likewise thinks that a similar method might be
employed for ascertaining the expansion of metals by heat. Tbns
by giving a wire a spiral form for the purpose of comprising a
considerable length in a small compass, a thermometer might be
constructed which should be capable of exhibiting single degrees ;
" using silver lor the lower temperatures, and platioa for the
higher ; or employing iron wire only, up to its ultimate point of
expansion in a solid state.
'Observations, — As Mr. Walker has not made us acquainted
with the constituent parts of his metallic composition, wcare not
able to judge whether or not it possesses the requisite qualities
which are stated at the beginning of the former of the above
quotations. In a note he observes, " The scale of this new ther-
mometer is an exact continuation of the scale in the mercurial
thermometer ; the lower degrees of the former corresponding with
or indicating like temperatures with, the vppcr degrees of the
mercurial thermometer."
Are we to understand Mr. W. to mean that his metallic com-
position and mercury undergo equal expansions for cqiial tem-
peratures at the degrees of heat answering to the lower part of
his scale? That there is a great difference between the increase
of the most expansive of the metals and mercury in lower tempe-
ratures, cannot be doubted ; that of zinc to mercury below 212*
of Fahr. being nearly as .0093 to .02; and the ratio of all the
others which have yet been accurately determined is still greater.
It may be concluded from analogy, that the expansion of metals
is progressively increased with the temperature ; but whether
in a geometrical progression, as the square of the temperature, or
as any higher power of the same, does not yet appear to be
clearly known unless ascertained by Mr. W. by means of his
new thermometer.
The great difficulty in the construction of such au instrument
is the obtaining two fixed points, between which the scale may
be divided ; and it does not appear that Mr. W. has discovered
any effectual mode of obviating this difficulty.
837
Ort the Influence of Solar and Lunar Attraction on Clouds and T^
pours. Bj/ Salem Harris, Esq.-^Fiil. Mag. No. I47. '
Th£ author of this con).Q9uiiicalioD Ktates, that on perusing tbs
theory of the tides, as originally laid down by Kelper and sub^
^quently improved by Sir Isaa9 Newton, he waa forcibly struck
with the idea, that if the sun and moon h^ve such iufhience on
the, waters as to raise those parts tliat are placed in the focus of
their attraction, the effects of their influence must be still greater
on the clouds and vapours contained in the atmospheie. This
influence, in conjunction with the wind or in opposition to it, he
thought might be sufBcient to produce those fi^eiquent and appa* '
rentiy uncertain changes which are experienced in this country;
^nd was much surprised that he could not find this subject had
been treated by. any philosopher. He therefore began to form a .
journal of the weather ; noting atjeach observation the moon'a
altitude and azimuth ; the success with which it was tittended he
relates as. follows : *' and I bad the satisfaction of finding my
infantide speculation so well grounded, that I observed the wea.
ther almost invariably thick or rainy, when the wind or moon,
being at or near the same quarter, were act'ing in conjunction ;
the latter drawing the clouds, as I imagine, 10 her nearest point
of the horizon, from whence the former drives .them over its
surface ; and that it became proportionally clearer as their relative
change of situation enabled the wind to counterpoise the moon's
a,ttraction, and prevent those vapours from collecting." In ISO^it
a voyage across the Atlantic, and a residencefor some months
at Havannahy enabled «the author to extend his observations to
the northern- limits of the trade winds, and to the torrid zone,
both on sea and land. Mr. Harris's principal object in the
present communication is to give an extract of a few days from
his journal for each of those different places v/here he made
his observations ; accompanying them with short comments
on the nature i)f the country, the prevailing winds, or the periodic
cal change of seasons. These extracts are : 1. From a. journal
kept at Wandsworth, near London, in October, 1800; 2. From
observations between Madeira and the Cape Verd islands, iti ,
March, 1309 ; 3. From a journal kept at Havannah, in Septeoi*
bei of the same year; and 4. From his journal composed be«
tween Bermuda and the Western Isles, in the following Novem-
ber. The first three of these specimens are divided into six '
columns each, and headed as follows : l)ap oj the Month ; Time of
the Day ; Whbd; Moon^s Jzimuth ; Moons jiltitude or Dvpre^^
Bum ; Observations. The last has a seventh column subjoined,
containing the Height, of the Thcrmomeverj at the time of obse^va- .
3SS On Solar and lamar Attraction.
tion. Among oth^r misceilaneous observations by wbich these
specimens, are succeeded^ Mr. 11. says that he considers the
strength of the wind as material in his theory ; but this is a
circumstance which did not strike him when he began his obser-
vatiops ;'^d therefore it is not noticed in the early part of his
journal* He also states* as his opinion, that tbe power of the
moon's attraction in assisting or counteracting the eifect of the
wind, diminishes in pioportion at her distance from tbe horizon
increases.
We shall transcribe tbe last two days from the last of Mr.
H/s extracts, with a view of illustratpg the form of his journal.
Bay of
the
Hot.
SO,
Time
of Day
Mora.
Eten.
£.
moderate
NE.byE.
moderate
I>ec.
1.
Morn.
Eyrtiu
mud
N.N.E.
modemte
N. by E.
moderate
Jiimuth
S.W.
AUHude or
Depreuiihi
Observatiofu,
45«^ Alt.
N. ,fil^ Depr.
S^S.W.
N.
fiS'^AIt*
65^ Depr.
tteighth «f
Thermemm
Fine: a fewi 6%"* SO'
cknids Hliich
clearing off.
Very fine: si few]
clouds to windward 08*
Mncfa niii be^
tv.cen U p.m. of)
the 29th and l!
a.^m of this day:|
the wind and moon'
hang nearly in diet
same point (£. by
N.) and the latter
on the Iiorizon.
Very fab* bat ta- 67*
ther cloudy* parti-
cularly sear the
moon*
Fair; but cknidy 67* S0»
in most parts of th^
horixon, pardciH
larly from N. to W.
Observatums^'^JThe circumstance mentioned by Mr. Ilarrxs, at
the commencement of his essay, relative to his not being abl«
to find the influence of solar and lunar attraction on the aqueous
part of the atmosphere, iioticed by ** the philosophical world,"
is to be ascribed to his wantf of information on the subject rather
than to any other cause. But for this his youth, (being at
school) and the consequent want of opportunities of becoming
acquainted with the works of the learned relative to this branch
of natural phenomena, account sufficiently. And the mode^y
with which he now i^ers^ a specitnen of his observations * to thi
ftotice of the pablic is worthy of U)e youthful student of flftture.
Ou SqIot and Lunar Attraction* 3$S^.
whose mind is occupied with objects of utilityi and engaged in the
pursuitof/r/i^ A— not of controversy. On this head, he observes,
^ I do not pretend to improve, much -less to controvert, the,
theories of those many learned and 'scientific characters who
have written upon the nature and variation of the atmosphere;, .
for my knowledge in every branch of philosophy is very sUgbt;
but, 1 cannot help thinkings that a little attention to the subject
which I have noticed, would frequently iiseist an observer of the.
weather, in foreseeing with additional certainty an approaching,
change ; and i offer these remarks to the public, with no other,
view than the possibility of their being investigated, by those
who possess the knowledge and Uisure requisite in philosophical
studies, to the advancement ^f science, as well as to the benefit '
of those professions, in which a dependence is placed upon the,
atmosphere/'
While we thus readily ascribe to the author of thie paper.
the merit due to his modesty, we would not withhold . from hin^
the praise of ingenuous confession ; as we fully agree with liio^
that his knowledge, at least of the subject which he has treateti^
*^ is very slight/' The following specimens transcribed from his
essay, we hope will answer a double purpose.: they will
tend to shew the ground upon which the coincidence^ betweeu his,
opinion and ours is founded ; and we trust that, should our re>^
marks fall under the obser rations of Mr. H. they will also have a
tendency to induce him to think more closely on the subject, and
to weigh the perspicuity and accuracy of his expressions with a lit*<
tie ntiore care before he commits them to the public in any f^turct
communication* We can likewise assure him, that in makisg
these remarks we are influenced by a feeling the very reverse of
acrimony ; our only desire being to.elucidate, or rather to exhibit,
truth. Mr. IK repnarks, ^' I observed the weather almost iava*.
liably thick or jainy, when the wind and moon, being at or near
the same quarter, were acting in conjunction ; the latter drawing
the clouds, as X imagine, to her nearest point of the horisoa^
from whence the former drives them over its surface ; and that it
became proportionally clearer as their relative change x)f situatioJi
C4)abled the wind to counterpoise the moon's attraction> and
j^event those vapuurs from coUecting/* Is not this very obscw#
and even contradictory?^ A little reflection will induce our
readers to 9gree w4th ua that it is* ^* Our atmosphere may tofir
toia at times so little vapour, «• to be incapable of produeiig
rain^, although the moon and wind were acting, ever so much ia
onison ; but this can always be ascertained by the state of the
barometer.'' Those, who make experiments for determining the
quanti^ of moisture contained in the air at any given time, «ir
conceive do not make use of a bairoraeter ^r this purpose ; but
«|f a very difEereivt iostTMinf ntj wlu4;hi Air. H« may, perlkaps, hav^
3 Id On Solar And Lunar At{raciiofi.
lleard desighated by the appellation of a hygrometer, Agdiri^
*^ when also the moon's altitade or depression is so great as Uf
place her nearly in the zenith, or the nadir, her attraction cad
of course avail but litfle, either in assisting or «ountera€ting Xh^
effect of the wind, from whatever point it may happen to blow i
its power, in short, must diminish in proportion a? her distance
from the horizon increases." Any person, however, but very mo-
derately skilled in the resolution or decomposition of force? would
find no difficulty in shewing that the moon's horizontal attraction
<)iminishes, not ^^ in proportion as her distance from the horizon
increases, but as the cosine of her altitude decreases,'
If we reflect upon the various causes by Which the equilibrium of
the afhiosphere is disturbed ; the great mobility doe to its flui-
dity and its spring ; the influence which cold and heat ba^c^ upon
its elasticity; the almost immense quantity of vapours which it
alterpately receives and deposits, and the changes which the ro-
tation of the earth produce in the relative velocity of its mole-*'
cules ; we shall not be astonished at the inconstancy and variety
of its motions, which it is extremely difficult to subject to any
certain laws. Amongst other causes of variation, the attraction
of the sun and moon must also be admitted. Laplace', hi his
Systrme du hfonde^ observes that in order to arrive at the ocean
the action of the sun and moon traverses the atmosphere, which'
ough( consequently to experience its influence and be subjected
to motions similar to those of the sea. From this cause result
winds and oscillations in the barometer, of which the peridds
are the sameas~those of the flux and reflux of the sea. But these
winds arc inconsiderable, and almost insensible in our atmosphere,
otherwise so much agitated : the extent of the oscillations of
the . barometer is not a millimetre (,0393702' English inches)
even at the equator where it is greatest. Yet as local circuni-*
stances cofisiderably augi^ent the oscillations of the sea; they
equally increase the oscillatio OS of thie barometer. "But the at-
traction of the sun and moon does not ' produce either in the sea
or 'the atmosphere, aily constant motion from east to westi those
motions which are observed in the atmosphere between the tro-
pjcs, under the name of trade-winds, have therefore another
canse. The diurnal elevation and depression of the bafofiaeter
in the torrid zdne, as observed by M. Cassan and others, and
-Wfakb has been attributed' to the influence of solar and lunar
attraction, has even been employed by De Lambert^ and other
philosophers to account for' the various phenomena of the wiuds%
&c. but notwithstanding the leariiing and ingenuity with which
it has been supported, it appears to be wholly rifadequate for the
the purpose. In fact, this variation has no observable relation
to any iwiar period; consequently it cannot be produced by those
forces which .occasion the tides, but must be wholly referred to
meteorological causes.
Mr,, Marrat on prime and ultimate Ratios. 341
Mr. Cotte, some years since, published a table m tbe Journal
fie Physique, from which it appears that the barometer has
always a tendency to rise from the morning to the evening ; and
that this tendency is greatest between two o'clock in tl^e after*
ndon and nine at nig£t, when it attains its greatest elevation^
The difference of elevation between two o'clock and nine at night
as g^^eraily about 'four times as great as that betV^en tWo anj^
nine in the morning; and is perhaps owing to the increased
quantity of vapour in the atmosphere at that time*
From a series of observations, accompanit^d by an explanatory
table, published In th^ 7th volume of the Philosophical Maga-^
zine, it has been inferred that the sun and moon have a consi-
derable influence on the pressure of the atmosphere ; the effect
of which is a tendency of the atmosphere to gain weight while
the moon is approaching to either' quarter, and to lose it again
during tbe approach of new and full nioon. The actual change
which, oh a mean of ten years,- has been supposed to take place
at London, is stated at 2-lOths of an inch in the height of the
barometer, and this occurs twice in each moon. The apparent
influence is likewise said lo be often much greater for a consider-
able time together.
For a curious account of the diurnal variations of the barometer
between the tropics, we must refer to page 15 of our second
.volume.
On prime and ultimate Ratios^ with their application to the first
principles ofthefiuxionary Calculus, Bi/ Mr, W» Marrat. —
Fhil.Mag. No. 14,9.
Mr. M. defines ratio to be the relation which two quantities of
tlie. sahie kind bear to each other; and observes, that the measurQ
of a ratio is obtained by considering what part or parts one term,
of the ratio is of the other : thus, if a and /^ denote the terms of a
ratio, •r expresses the ratio; of which b is called the antecedent^
and a the consequent ; or sometimes the terms of a ratio. If these
terms be equal, the ratio is called a ratio of equality ; if they vary^
the ratio may have any magnitude ; and if only one of the terms
-vary, the measure varies with the varying term. Let -represent
any ratio, and let a remain constant, while b is variable ; it is
obvious, that if 6 decrease, the measure of the ratio will increase ;
and when b is become indefinitely small, the measure of the ratio
is then indefinitely near to a ; and when b entirely vanishes, thQ
measure of the ratio is exactly equal to a.
On the contrary, when b increases, the measure of the ratio
No. 25. — Vol. ti. 2 t
}J4l ^r* Marrat on fwne and ultimate Ratio$
decreases, Agaii:, U t b remain constant while a is variable ; Acn
as a inert ases, the measure ot tlie ratio increases ; hut it decreases
as a decreases *, and when a entirely vanishes, the nuasnrc oi th^
1 *r ""I" ft
ratio is equal to-." JMr.M.tiicn assumes as an example,
which he treats in the same manner as before; and concludes by
observing," when x vanishes, the r^tio is equal to a exactly."
From these illustrations Mr. M. considers it extremely obvious,
that the measures of such ratios never can attain the limits assigned
them, but continually approximate towards them, till they differ
from these limits by less than any assignable difterence, and then
they may be said to be equal. Ihus, by making use of thesera-
tics in their ultimate stale, we obtain results indefinitely near the
truth ; and, in practice, the indefinitely small error may be neg^
lecU'd without deviating froni the truth by any sensible magni-
tude. Ihis, Mr, j\l. thiniis, was all that Newtoii meant in the
first lemma in the Principia. Reasoning thus, he arrives at the
following result, " that the conclusion obtained by the method
of fluxions is not ab&olutely tnte^ nor did Newton ever consider
them as such ; they are approximations which prodi^cc no sensible
errors"
The first method which the ancients employed for finding U^
areas of curvilinear spaces y,'m thut i)t' exhaustions. But as this
method was often long and tedious, Cavalerius invented the me-
thod of indivisibiei ; but these frequently led into perplexities,
and sometimes into error. It was to avoid the tediousness of the
foimer method, and the errors of the latter, that Newton invented
his metliod oi prifi>e and vltimate ratios. In applying this method
to the quadrature of all kinds of spaces, its great author supposed
one or more ot the sides of the figure fo be in motion, and the
figure to be generated by their extreme points. Mr. M. giv«y
txampUs of this mode ot generation, as applied to the square and
rectangle, by supposing them to be generated by the motion o^
two right lines, which are also at right angles. Thus, if.r and jf
denote the sidts of a rectangle, aiui by the motion they become
a .
*-|-^> jZ+.j/ ; then the fluxion of the area of this rectangle will be
•• .... .»
(x + x).{y + v) — xt/, or xy-^xi/'i' .ry . I lere, by su pposiilg x and 5
to be in a nascent state, the rectangle j:y may be neglected, with-
out en^ibh" error-, though the result will not be strictly and geo-
metricdlly true.
ObiieiTations* — After perusing this essay with consielerable at^
tention, we are lorced to confess ourselves at a lofes to discover
the object of its publication ; unless we regard it as an attempt X9
elucidate the elements of the fluxionary calculus ; And in this
aeiise, whatever may be due to the good intentions of the author^
Mr. Penwarne's Patent Jhr improving- Statues. 34$
^c certainly can neithcF congratulate him on Ms succpi^s, norad-
■ iiait several of his conclusions. SVe l)elk;ve tb^t it is allQWc4 tiy
■
must nMthematicians, that it t denott the inrasare of a ratio, and
the denominator vanish, the measure then becomes equal to infi*
nlty, OF - ZZQ^^ ^.nd iH>t jequ^l to a> s^ stated by ^^\ M. Agsia^
Wtien* <r becom<*8 nothing in the preceding expix*ssion, the measure
ci the ratio is r =o, and not j as given abyve. In the example
, when X vanishes, Mr. M. appears to be equally unfortu*
aate in assigning a for the measure of the ratio iristead of oo.
Mr. M. observes, that " the conclusions obtained by the roe-
tiiod of fluxions are not absolutely true"* ; ^ut we would ask, is it
not " absolutely true^" that whvn ax — X^ is a maximum, orzrja;
or that the greatest cylinder that can be cut out of a cone is at
^ of its altitude ?
PATENTS.
Jjfr.' JoiiN FeUwarnf/* Patent for a process for giving to^tut$^
or other ornamental H^orks, in Flatter, an appearance nearly
resembling t/iejntst Statuary Mfirble. Dated September ISOp.
— Repertory of Arts^ No. dS,. Second Series.
The principle of this invention is, to impregnate the planter of
.-which the articles are composed with a solution of alum. IlJ
or4er to etfeci tUii^ purpose, about a pound" of alum is put int^
isvery three pints x)! water, and the liquid then raised to a suffi*
ciept temperature to dissolve the alum it contains. The plaster
cast, previously dried, and properly tinished, is then imn^erscd
iu the solution, andsutfered to roiuiia from 13 minutes to baU' aa
tour; afier which it is tLikeu out, and suspcuKled over the vessel
containing the solution. It is then suffered to coo) for a fevf
minutes, and some^ of thq solution is applied to it by' means of s»
spunge, or linen cloth ; and the operation continued, till the
alum'' forms a fine crystallization over its surface, of a proper
thickness ; and then brought to a polish by means„of sand-paper
^r glass-paper ; and then finished by rubbing with a fine Imea
irloth, slightly moistened with clean water. Tluj patentee makes
use of wooden vats, heated by steain, for preparing his liquor, to
^yoid the tinge which most metallic vessels would impart to it. .
Mr. P. remarks, in his obsef vations, that he " has the satisfac-
tion of submitting to the inspection of the public, at his ware-
iousc,, No. I2f Pickett-street, TemplcTbar, a beautiful imitatioii
' 2 y 2
]3M Mr» Groves* s Patent for an improved construction ofBuilMngs*
of statuary marble, in busts, statues, &c. after the most oele-r
brated ancient and modem masters :"' that this preparation pos-
sesses ^^ the beautiful whiteness and transparency of the finest
statuary marble, at the same time scarcely yielding to it ia
hardness, and (for purposes of internal decoration) in durability.
It is jiot affected by the moisture of the dampest apartments ; and
is even less liable to soil, and as easily cleaned as marble. By
means of this invention, exact copies of the works of ancient and
modern sculptors may be obtained, at a price i^ot much exceed-
ing that of plaster."
■ »■ ■■ ■
Observatwns. — The plaster cast affords a facility of obtaining
cheap and correct copies of the most valued labours of the sta-
tuary, which is unequalled by any other ; but its colour, softr
ncss, and liability to soil, were circumstances that greatly dimir
nished its value. The method proposed by Mr. P. appears well
adapted to counteract these effects in a great degree, by adding to
both the beauty and durability of the statues which are subjected
to it ; while its cheapness and simpHcity are further jecommen^
dations in favour of its adoption.
Mr. John Thomas Groves'* Patent for antmproved mode of
constructing Buildings, by which great expenccy labour^ and time
: ' are saved, and the Building secured from the dry rot, wth other
advantages. Dated April 1^9^— Rep, of Arts, iVo.98. SecSeries^
Mr. Groves commences his specification in the usual way, by
declaring that his '< said invention is fuHy described in the draw-
ings hereunto annexed, and the following -description thereof.*
The drawings consist of fourteen figures, each accompanied 'by a
descriptive sentence; and to these figures we are under the neces-
sity of referring our readers ; as no information on the subject can
certainly bo obtained independent of them ; arid those who learn
any thing from them will accomplish what w^e have not been able
to do. We transcribe the two following sentences as a specimen
of the manner in which the title of the si)ecification and the decla-
ration at its beginning is fulfilled.
" Fig. 1: Plan of an internal wall, nine inches thick, shewing
the. apertures for air. >
" Fig. 2. Plan of an internal wall, nine inches thick, shewing
the aperfures for air within the thickness of the floor ; a, apertures
either six or nine inches high."
These sentences are multiplied till they equal the number o^
figures, that is to 14; but each is expressed in the very same
words, with the exception of those words which indicate the dif-
ferent thicknesses of the walls, and that of external being written
'■ for mtcrnal in some, places. Thus ends the specification !
Jfr* Goddar^s Patent for a method of making Chip Soxe$. S4S
Observations^ — ^Mhen we first read tte title of Mr. Groves's
{»atent on the wrapper of the Repertory, we were induced to ex**
pcct that its specification would describe an invention of consider-
able public utility ; but on opening the l?ook,' we were soon con-
evinced, that our expectations were much too high, as we found
nothing described that has any connection with the title. But as
•Mr. G. has declared that his invention is fully described in his
specification, and as we have not the least reason for impeaching
"his veracity, we can only conclude that his inventiony and the
title of this specification, have not that connection with each other
which should necessarily subsist.
We are sorry that our duty again compels us torerert to the
principle, that the law, which places in the crown the power of
granting letters patent, as an incitement to the exertions of genius,
and the public reVard of these exertions when successful,' require*
that the specification" upon which the patent-right is granted siialt
describe whatever the title imports, in such a perspicuous and .
tninute manner, that any competent but common workman may
execute the design without employing any invention of his own,
and without any further instruction being necessary than that
'which the specification furnishes. We, however, who are much,
accustomed to the contemplation of such things, even were wo
able to handle the requisite tools, certainly could not construct
;such a building as the title implies, without further information
'than is given in the specification ; and therefore think it fair to
conclude, that no common workman will be found who can.
Mr. James Goddakd'* Patent for manufacturing a certain de^
serif tion of Wooden Boxes, called Chip or Pill Boxes, Dated
Januarif IS09' — Repertory of Arts, No, QS. Second Series.
The machinery which constitutes this invention consists of
several parts, arid is adapted to the purpose of cutting wood into
chips, veneers, or thin plates or boards, for making boxes, and
other uses. In this apparatus, a strong frame of wood, or other
fit materials, supports a moveable piece called the carriage, which
is moved very" steadily along grooves made in the frame ; and
- ivhich, on account of both strength and precision, the patentee
prefers being made of metal. This carriage carries along the
' knife or cutter, which is made of plate steel, having the edge
"bevelled on the side farthest from the wood intended to be cut;
and the line oi' the edge is inclined to that in which it is moved by
' the carriage (while cutting) in an angle of about 30^ ; which th«
patentee states, from experience, to be the most useful or best
" jadaptcd to the required purpose, though the chips may be cut
Very well with other angles considerably diflferent from this,. Tha
^4f$ Mr. GoddariTs^ Patent fen- a method qJ mailng CU^ Boxti.
4rst mentioned horizontal frame also supports a metallic platfoxm
upon which the wood to be cut is fixed ; and in which a groove if
Hi^ide, wherein the lowest part of the cuUing-knife moves, and is
firmly supported, so as to prevent any side nioti^m or shake in the
$ame. The carriai^e, also, supports a moveable gauge or cutter,
which cuts cross-wise with respect to the knife, and cuts a line ia
the face of the wood, which is afterwards shaved off by the knife ;
by which means the shaving is separated into two or more* pieces
of the breadth required. The carriage is moved by means of a
fkmn or strap fixed to it, and to the axle of a wbeel turiuBd by
winch handles. >
When the apparatus is to be used, the carriage, with its cvtter
/Mid gauge, is moved to one end of the frii,me, and tbe wood, being
£rst properly shaped, is fixed on the platfopm, with its face a
Iktiie beyond the groove in which the cutter laoves, and is kept ia
this position by means of screws. The first molion of the cutter
j»long the platform takes off a slice or shaving, and prepares the
wood for its future operation. The carriage is then moved bacl^
mid the handle by which the screws that regulate the thickness^ ojf
, ilfae slice to be cut are moved, is turned one or more turns, as^ th^
thickness requires ; and the carriage being again brought foiiwardt
now takes off a shaving orUniform thickneps^ and proportioned to
^e motion of the. screws. Proceeding in the same manner, tlu9
-whole of the piece, except a thin portion, may be cut ; and seyiCr
val of these remains may then be glued together, and cutix^t^ sha^
ings.as before, if required.
Mr. G. also describes a tool for cutting out the tops and hot*
tems of b^xes, or for other similar uses. But he, in general,, per-
forms this part of the business by means of a seat and cutting
launch, worked by a fly-press, in the same manner as lyetat^c
blanks eire cut out for coins, buttons, and other similar works.
The pieces are cut. into lengths by gauges, and glued upon cylin-
ders or blocks in the usual way ; and put to dry in cellsor frames
which do not require any particular description.
Observations. — Pcifhaps some of our readers may, at first, (Jiink
the manufacturing of chip boxes is of too trifling a nature to hav;e
merited the distinction of a patent ; but when the vast numbers of
them which are daily used, and therefore the necessity of having
them afforded as cheep as possible, are taken into, the acco\int, we
think that any contrivance tending to facilitate this species of
manufacture deserves encouragement; especially atajtime when
it has been impossible ,to procure the usual supply ^rom theconti-^
nent. The present machinery appears to be well adapted to the
• purpose for which it was intended ; and easily suited to the nature
.43f the work to be performed, or to be accommodated to ^he local
cifcumstanccs^ of the situation. -
( 34?»
Iff. William Dockbey's Patent for considerable hnproretPtnU
in tJie process of moMLfacturing Ivory Black; andforjruherudvg
^U articles capable •fa more easy separation of' thir parts or
q»nstituent principles. Dated May ISlO^—Uepcrtoiy ^Artsi
No, SQ, Second Series,
TrU in<ventu>n of Mr. Docksey consi^ in rrd lining ih« sel^rrt
ftrtkles to a fine powder, without the use of those Coasiderabi^
qvanttties of water that are now employed. For the manufactuiv
<if ivory black, he takes .the bones and the Sfloughs of the bams of
Animals, tLnd calcines them to blackness in air-tt^ht vesselfii
They are then crushed in their dry state between metal rollers^
t^\ they are sufficiently broken to pass through a hopper into th^
eye of a mill-stone, by which they are reduced to a fine powder iii
the same manner as com is reduced to flour. The powder thutf
obtained is then passed through a dressing machine cohstmcted
with brushes in the usual way, the meshes of which are aboul
«ixty^ight to an inch ; the part which passes through is fit fo#
use, and is damped down with a dmall quantity of wat^r (br sale %
liie remainder is returned to the hopper and ground again*
- With respect to flints, potters clay, colouring and glazing
materials, this patentee pfl<)ses them in a dry or calcined state^
linder stampers or heavy hatnmc'rs, till they are sufficiently reduced
in size to press between metal rollers, after which they undergo
th« same process of grinding* "and dressing as in the former caeej
The powder which ha» passed through the dreijsing machine i#
then mixed with water in, a deep vessel ; by which means the
coarser parts are again st^parated by subsidence ; the thinner parts
ef the mixture are then passed thr^mgh a fine lawn or cypres^
meve; after which fhe wat^r i« dhiined off, ^ and evaporated by
beat from the substance ; and the ' powder thus obtained is «f
superior fiiieneas.'
— ^ I
06*pnwifwtt«,-r-This method of manufacturing ivory black* it
-certainly calculated to save a grieat d*al of the time, labour, and
cxpence, which -were neeiessary in the processes • previo«sly
Adopted for the same purpose ; and We think^ with the patentee,
thst the "Colour will -be better preserved. His mode of separating
the finer parts of the pulverized eolburinjg or glazing materiak
-will also bee^ctual-; and the fineness of the powder must^contn«
iMite to the jdelicacy and beauty of our porcelain manitfactura^
-£lut in order tO'eBtiinate the precise value of Mr* Docksey s invent
tion^ it would be necpsaary to compare it more acctimtely witht
<lie modeahitbert* employed than we bay« leisvrt to ile tifeprewii»«
( i4s )
mssm
Mr. low Craig e'j Patent for an imyrofccd Kitcken Tlre-^tace^
Dated Febrvary 1 810. — Rep. of Arts, No. 98. Sec. Series.
Mr. Craige's " invention consists in the application of tb«
powers of an air furnace to give heat externally, and in using
tond, iron, or other dense bodies, to receive and retain such heat,
to be employed for various useful purposes*" To effect this on a
small scale, a base of stone or brick work is to be constructed,
about four fc^t long, two feet eight ificbes broad, and twetity
inches high ; the chimney grate, about eighteen inches wide, and
six deep, is to be fixed near one end of the front. On this founda«
tion two sides of artone or brick are to be raised, about nineteen,
inches from each other, and extending through its whole length ;
these sides are covered with a pan of cast iron, resting upon rims
placed upon the sides, which raise the pan aboyt half an inch
«bove them. The depth of the pan is to be about six inches,
'' and will be raised above the basis, so as to leave An aperture
throughout of about an inch and a half/' This aperture te.r|ni-
nates at the end opposite to that which contains the firergratef in
A flew leading to the chimney, which should be furnished with a
damper. A plate, projecting from the lower end of the .pan,.
iforms the top of the fire^place^; its back and side» are.mad^ of
brick-work. The door on the front of the fire-place is to.be:about
.eighteen inches wide and sixteen deep; extending about . four
inches below the grate in front of the ash-pit ; a grate of about
five or six inches high is placed in front of the fire-pla^e ; and ar
^mall door, three inches wide and two deep, opens in the large
door, to admit air through the ash-pit when this last is shut. If
wood be used for fuel, the depth of the Ere-place must be increased*
The following are the purposes to which the patentee proposes
this improved fire-place to be applied : viz. *' The iron pan being
filled with dry sand will form a sand bath, with heat sufficient
According to the depth to which the vessel is placed in for all
ordinary purposes, and bein^ once .hea^d will retain >he heat
for considerable time; especially if the doors are kept close shut;
the plate or front will serve for broiling or frying ; roa9ting nuiy
be performed to perfection before the door in front, even with th^
doors shut ; an oven for baking may be fixed at the flue.'' In 9ome;
observations by which the specification . is succeeded ,.in thet .
Repertory, the patentee states the saving of fuel to be full two
thirds of the quantity now generally used.
Observations. — As Mr. Craige's specification is not accompanied
with any illustrative engraving, it is not easy be understand
the construction of his improved kitchen fire*pjace, nof to ascer^
tain its fitness for the intended purpose ; but if it will efiect what
be asserts, viz. a saving of two thirds of the fuel generally osed^
it is certainly worthy of adoption in various parts of this countr j
Mr.Witt^i fatentfcr'eert'impwrhf^rotatiocSie^ 341
where fuel is so expensive ; aiul particlarly in the metropolis and
its vipinity. . i
Jfr. Richard Wit^ty's Patent for making, arranging, and com"
bimag certain Farts of rotatvoe Steam Engines, by uhich m eons
the most complex Farts of the Steam Engines now in use are dis^
ptnsed with. Dated Feb. ISlO.^^Repertory of Arts, No. 99^
Second Series, ' ^
Mr. Witty states that his inveDtion consists in making,
arranging, and combining the reciprocating rectilinear motioa
with the rotative in such a manner that his steam cylinders, with
pistons moving in them .in a rectilineal direction, do at the same
tame turn upon a horizontal axle or shaft, and partly from .what
is commonly called the fly*. wheel. By this combination of the
cylinders upon or in a vertical wheel, he effects a complete
rotative engine, with pistons moving in straight lines in their
cylinders without interposing a beam, crank, or other contrivance
between the rectilineal and the rotative, as in the engines now in
use ; and which engine, thus combined, performs the filling and
discharging itself in a superior manner without the aid of valves
or cocks, consequently the gear, denominated the hand gear, is
also rendered u^dtaectssary. Mr. W* then shews in what respect
his invention differs from the rotative steam-engines without
Veam, crank, &c. made by others. In these last the pistons
have been made to revolve about a centre ; but in the present
invention the pistons do not move round a common or concen*
trie axiS) but in straight lines, like those of a common beam
^gine, and are at the same time with their cylinders carried
round upon or in a vertical wheel, which operates as a regulating ^
fly-wheel. By this means the pistous acquire a compound mo-
tion, and describe a curve, varying with the length of the stroke
and the speed of the engine.
The patentee describes several varieties in the manner of
esffecting this, of which the following is one t Pour c^^linders are
£xed, at right angles to each other, to a hollow nave or axle, by
laueans of screw bolts ; and the pistons working in those cylin-
ders are made tight at the extreme ends of the cylinders with
common packing. Each pair of these pistons is connected
* together by reciprocatmg rods, which not only unite their forces,
'km are of essential service in opposing the centrifugal forces to
each other. These pistons, thus connected together in pairs,
must be made of such a weight that a vacuum in' one of the
cylinders may easUy raise them both together in a perpendicular
^iirection. An axle, which is fixed horizontally is ground dr*
tight into the hollow nave, like the key of a cock, with two ducts
or tubes in it ; tine of these tubes is placed at the upper side of
the. axle, and is coimected with the steam pipe; the other is
no. 25.— VOL, VI. 2 is
J4C Mr. Hltt/sFUimf/arcertlMpartiofroffetkeSte'j^E^inetk
HxmI on the oftposlite side, knd joined to the pi)»e that leads to Ul»
condenser. Each cylinder is made to communicate thrOugbL
the hollow shaft where the two ducts in the iix^ axle (which ,
resemble two water ways in a cock) correspond with each other ;
and, at feach half revolution, the holes in the bottom of the
cylinders open alternately into these two ducts-. The hollow
shaft must be rtiade of sufeci^tit length on each sirfe of the wheel
to admit cff being supported ift brasses and of the application of
mill-work. The cylinders and pistons being thuis arranged, and
One pair of them being nearly in a vertical position, if the sleani^
be admitted into the upper cylinder, by the proper dact, its ex-
pansive force will raise this pair of pistons, and destroy the
equilibrium of the wheel, which will be caused to resolve by
means of their gravity. In revolving each of the cylhifdefs will*
be filled with steam from the upper duct, and discharged when
th^y descend to the lower one. Thus, affcier th« cylinder has
cleared itself of air at the commencement of its operation, whicte
may be done in the snme way as with others, the lower cylinder
will always be under a vacuum, while the upper one connected
v^ith it will be receiving steam from tfie boiler. Hence the j)is*
tons will evidently be constantly receding from the centre otf
one side of the wheel, and approaching the centre on the other.
With respect to the discharging duct, the patentee observes, ^ I
make the duct of such a size or capacity, that the cylinders pas*
it before the pistons are brought home ; so that part of the tie*
condensed fluid is left in the cylinder^ andy by being pent up by
the momentum, it returns the impetus as ^oon as the opposite
cylinder empties itself into the condenser, and this elastic fluid i»
discharged again into the steam duct, and adds tb the common'
stock of Steam in the boiler. By making use of this uucoudensed-
fluid in the manner just described, the motion of the engine is there-
by made perfectly smooth and easy, and the momentum of the pis-
tons is employed (if 1 may be allowed the expression) in bolting
up power, which is thrown into the rotative continuous motion.
Some other varieties in the mode of obtaining the same object
are described by the patentee ; one of which is, that of diakin^
the cylinders moveable instead of the pistons. The engine i&
also m(*de to have double effect or power by connecting the
extreme end of one cylinder with the end of the opposite which
ift nearest the centre or shaft by means of a pipe, and causing thfe
piston rods to work through stuffing boxes. But for further
particulars we must refer to the specification and the pfates by
Which it is accompanied.
'the patentee states, in his observations, that it is from actualr
experioiei^t that he is induced to prefer the invention described in
the preceding specification, chiefly on account of its siniplicity
ahd e«kSe of construction ; also that he had found that ^istooe.
mom Vfi^ gvf^ifur fgc^ty, m^ xmjcb ^t^r, m b ^tr^igjit Im
tli^n in ftpy fyttmr direction. . He likwie* poA<jews that by thi#
jsoAite of hai^ging ibe cylinder* upon tte . fli^'^hfi«l, bi» eagipp
4[j!Qsse9s^ iM 4497fLiit.ftge9 /9f both tb^ r/ectjijin/^ tg^ci rp^^uv^
ienginesy and approacbes towards a mhifiitm .of tbie .4i)99<iy0Dt4g^
jpfeacb.
Tr
. Ob9fi/w^ti<m.'^A eMrsory pery9fkl of tbi» l^ticl$ viU ^vioice ibal;
Air. W* dQ#» QO.t (mnd hia dai/s tp A^^velty, like mw» patentff^,
on tbe innovation of fixed principles; bujt 9olely op «9ikkipg Mui
arranging those parts of bis engine which we have described ; and
for combining the principles of rectilineal with those of rotary
potion. . ,0n this bead he asserts, |.h^ he b4§ ^' fprju^d and
jnade ^ coinpietef simple, and effect^ vis ei^^ini^ or engines/ by
which the pow^f obtained frpija steam, both l?y expansign j^nd
/eondensatioby is communicated tp mapbinf ry^ &|e. ^t a compara*
iively small expence, and, with some advantage in the saving of
#id.'^ -One circumstance which we regard as favourable to this
Ertentee's invention, is that his theory appears to have been con-
med by practice; and an engine of the kind for which tiie
ftt%e^ was obtained actuafly constructed and at work : and wp
'imagine that the principle can scarcely ever be' extepded to
'^inechines of great power ; the weight of the cylinders to be
my»wi^ and the inequality of the wear of the pistons feeing likely
"to-be very serious objections.
* -- ' *
'jBtr. James Hall's Bttteni for n^aldfig S^v^rs apd Pmtley Wheeb
f ifEarthi and Minerals, Dtfted November^ 1 HQ^.r^Repi^rtqfv ff
i Arte. No. }'00. Second Series. •'
T6e ipaterials used by Mr. Pall ii? foxifjipf^ W? cprnpositin?^
*j^re ,cjay or earth th^t contains ^i^ls^ou^, witceous, calicar^9ju#,
land niagnesian earth, powdered calciue4 i^^on ^!^Q^Cf afi^ pul*
yerised g^ranite^ or any vitrifiabJe ^tJom, ^vbetb9r jcalcjin^d or not,
Tbjs' mixture IS to be madp in^Q a p^^t^ wi.tb watejf^ mi ^tof
^jBJng blended together and tempered into ^p^^s, tp be wwd intp
fii^ required %rtic]e by ^jjeapg of ^ nwiJd, qx any other method
^m^loyed 19 jn^king earthen ware ; apid the^ to V baited or ftred
IP a common poitter's oven, jtill it becpfae sufficiently .firn> ^nd
jp.ar^ fof fti& intended purpose* Different article^ requir/e diigsrf^t
'degrees of heat, which an experience*} workman villj^^adily ^^ply ;
3nd various proportions of the , above mentioned ingredients may
fji^q h$ j^sed. Ppc of these compositions conpi§ts of seven parts
pf day, two jpart* of calcined iron ore, and two parts 0/ granite ;
jQr t\yp pj^rtf of Corneal] stone, or any other vitrifiable eartji naa/
■J^ ^u^bstjtuied for this Jalter. Other proportions ire thirty par^
it^fajr^ Wi^ twenty parts of calcined iron 'ore, and two of Corni*
544 Mr.WWmHi^s taUM for Tmprdtmenii m C^^
vail stone. Many differtnt metallic ores and oxyds may-lMi
used instead of the iron ore, and mixed-wiih any stones of the
kind mentioned above, or with those which contain manganese^
and the composition will acquire sufficient hardness for the re*
quired articles by baking.
Obseroations.'^There can be doubt hut that Mr. Hall's coropo^
sition may be rendered sufficiently hard for the intended purposes,
yet we apprehend there must be some difficulty in giving it
the requisite truth of figure.
P
Mr. JoHir Williams's Patent for certmn Apparatus tobe appUed
tOf and used wth^ IVheel Carriages^ in ardir to render the sam
more safe and commodious, Datec^ fvne^ 1810.— jReper/ory ^
Arfs^ No. 100. Second Series.
I
This apparatus Mr. Williams denomios^ a preserver ; it emir
^ists of (wp branphesy the fpretnost of which is made longer tha^
the other, anfi ^eir Ipwer extremities lie nearly in the plane oif
the wheel, Tbe%e branches are connected together by a strengtbeqr
ing piece, and unite in a ^pket at the top, whi^h contains a hole
for ^ pin, bolt, pr screw* A proper spiiupe is. oqade fast to the
<|kxl0-»tre^, and yrhen t)ie preserve^r is in its place, is passed throogli
the secketf and fixed by a bolt or screw. A pair of these pres^r^
ers is to be applied to a two-wheeled carriage ; one near each ex-
-tremity of the axle»tree. ^ The effect of my said apparlttus, or
l^dditional pi^rUf, is po preyei^t the great danger iq fi t^q^v^^f^
carriage, when, by a fall pf the horse, or any part givifig way»
the body might be thrown /orward or backward by a motion on
ih^ axis ; for i|: is the pianifjpst effect of nay said apparatus to rmm
ceive and support ^he carriage nearly in the horizontal positioiiy
'without the possibility of any considerable tilt or inclination, ei«
ther forwards or backwards/'
This apparatus noay likewise be applied to four-wheeled canit-
ages for liie purposes of preventing accidents, when a wheel either
comes off, or is incapable of affording the adequate snpport to tbp
carriage. Spindles are to be fixed to the axle-trees as before, hat
below theni instead of above ; apd the brace of the two arms oj:
branches is to be curved at the bottom, by which means it .actit
ivhen brought into motion, as a sledge, upon which the ci^iagQ
will he supported and suffered to move.
Observaiions.'^The great number of accidents which h^ppezi
from carriages of the description, for which .these preserv^
ers are intended, renders any invention that tends to prevent
|bexii^ of considerable public importance ; and we think expenencc^^
Mr. C(mgreoe*s Fatadfor a Scuriti^ agamit Fhe. 941
i^l prove that this is not ill adapted for the intended purpose.
In some observations published on the wrapper of the Repertory,
Mr. W. recommends, that these preservers be made of well tem^
pered steel, which will admit of their being made strong, light,
and somewhat elastic. They need not be made to we'igh mor^
than 30lbs«, per pair, and may be removed at pleasure to any
axle-tree now in common use by any competent workman. Their
situation also renders them serviceable in preventing the frequency
of overturns in light carriages, by diminishing the distance be-
tween the road and the centre of gravity of the carriage.
m
ilr. William Concreve's Pa^enf ^br a Mode of Comtructiou
qr Arrangement /or any Building so at to cfford Security against
^ Fire, with other Advantages. Dated February , I8O9. — Reper-^
tory of Arts, No. 100. Second Series,.
- Mr. Congrrve specifies the did^rent parts of his invention in the
following terms: ^' First, This invention cempreheiids a fire^alarum
^bich in case of fire breaking out, shall ipstantly give the alarni,
and ai the same time indicate the precise part oftkt home in which
the mischief has arisen. Secondly, It comprehends ah apparatus
for extioguifthing ^re^ which shall be called into action by the
£r# itself at its 4tst breaking out, and which shall be brought to
bear upon the precise p^rt where the fiames exist. Thirdly, The
means of extinction niay be applied in conjunction with the alarm
or without it. Fourthly, The meaps pf eytinption may be either
external or in ternaL All which varieties of the combination may
)>e applied according to the convenience and necessity of the case/'
In dwelling-houses, where saving of expence may be an object,
ft good security would be afforded by the fire alarm alone, and
ifithout prpvifling any particular means of extinction. In large
buildings and where few person^ ^re op the spot, the alarm would
not be sufficient .without the means of extinctioq. And in ware*
Jionses and such buildings as are sometimes left without inh^
bitants the alarm is only a supernumerary agent in the . combinii-
.tion, and may be omitted as thought proper ; Mr. C. then sp<y-
cifies the mode by which these object^ are to be accomplished, a$
follows.
In any convenient part of the houstf an alarpm is to be ^xt^,
the detent^of which is cpnnected^with 1^ lever, 'whicb being pres-
sed down io any part will set off the fdariim. Qver this
lever a number of small weights are suspended, equal to the num.
;.|»er of rooms in the house, each indicating the ^particular room
iv7ith which it communicates by means of a cord or wire. The
4^ver is provided with a stop, which being in the weights may rest
jamxt tl^ lever without discharging the detent. When tl^
glarujif is to be set^ tb^ cord belonging to facb weight is tQ be
^
#
fiifi ^ Mr* CtmgrmtU Patent for a Security afdaf4t JRrv,
drawn tight or so aB to raise the weigfit a few inches jkbovfeti^
lever, and then carried two or three times across the room, and ibp
]^d made fast to keep the weight suspended. The stop being
withdrawn, any incipient £re will immediately bum tbrougll^
isome part of tbe cord, and the weight attached to it being «et at
liberty, will discharge ihe alarmn, apd point out the particuUf
place in tlie house where the fire has taken pl«ce, ' This sam^
apparatus, by connecting the cord with the window shutters an^
jloors, will also become an ajiarm against robhers as well as fire^
By this mode oi fastening, the ]ine woul^ also cpme mio contficf,
with the curtains, which are the parts of furniture most likely
to feel tbe efi«cts of a lire at its (kst breaking out.
Tbe tire alarum thus describjsd requires to be set every nighJt,
)but there is a variety of modes of obtaining the same security,
and thp a^rum remains in a constant state of readiness. '^ Tliua
the cords, wires, or means, which keep tbe weights in suspension
may be passed round ^nd about the room, either concealed W*
liind tbe paper, under the Aoor, and above tbe ceiling, or wSbb^
idong the cornice; in which situation they may be made an
object of ornament, with festoons or pendants, of some rapidljr
inflaming matter, which shall, in case of fire, quickly communicala
<with the main cord ; or the leaders may -be concealed by a i4ighi
heading round any part of the room, so as to be disposed to lise
"first lifects of £re, and so as in either of these modes to be iti
«i constant state of preparaiion." Hie «ame may be effected by
liaving the ends of tbe cords fixeid by means of certain cements,
'which will give way at a comparatively low temperature ; or tha
cords or wires may be discharged by means of a mercuria} or
fMiher thenxxometer, rwing a piston by the expansion of the
-(Suid which it .contains.
The patentee also describes a method of constructing an alamm
with an indei^, which shall point out the particular room on fifs
1»y llie action <^i one weight only.
Mr. C. nextdescribes the second part of his combination, namelir
-^e constructioaandarrangement of the apparatus by which the fins
ktobe extingniehed. This is accomplished by means of pipes whi<^
conduct the w^ter to the piirt on fire ; and l^e water is let intp
^hese pipes by similar or even the same means Uiat havte already
been described for discharging the alarum. A cistern is to. be
^jlaced on tbe top of the' building, with pipes leading from ft to
the 4l^rent rooms. Each of these pipes is provided with k
^aVve or plug, which when struck prevents the water from
passing into it. These valves are also connected wi tfa* the same Hne
"which discharges the alarum ; and hence the v^ve is opened an^
the alarum discharged at the same time.
The water thus conducted to the room is to be dispersed in i(
sJiQwer throughout it j either |rpm the whol? wline or any par««
Mr, Congrece*8 Patent fit a Skcuriiy dg<unsi Fire. i^f
titular part of it prepared for that purpose, either by makiag it
full of small holes, or Working ir into an ornamental patteriii
This niethod appears to be best adapted for theatres and other
Targe buildiogs*- A method better adapted to common dwelliug
bouses is that of causing it to be dispersed from the cornice, round
the robm^ with SLj'et dean from the centre of the ceiling, or from
each corner of the room. These means of extinction may alsof
be limited to particular objects, as to a bed, the drapery of a cur-^
tain; 6tc. or they may be provided in particular rooms in casc^
of accidents to ^hich the clothes of women are so liable.. In thd
first moment of the misfortune the sufferer might have recoursQ
to the handle provided for the purpose, and both give the alarm
and produce a shower of water fot the extiactioa of the flames^
before any serious injury had been received.
The external means of accomplishing the extinction without
a reservoir is next considered. The first of these is by a forcing
fiump at the bottom of the bous6, to which on the firsi alarm tha
inhabitants may immediately apply ; and from which the stream
18 to be conducted to the fire by . the same system of detents^
^ves, &€.
But a more important means of extinction is that of ^aus*'
lug Um water of any number of engines to be thrown into any
fMirticular part of a house^ by means of conducting pipes leading
from the street to the cistern provided for the purpose, and con^
liected with the difi'erent rooms as already described. ^^ By thi«
arrangement, therefore, ten or twenty engines n>ay be made ta
pour their contents into the particular part of the building ia
flames, so that not a drop of water can be thrown in vain; and even
if the fire shall have made head, it mast soon yield to the force
of water so brought to bear upon it, and surrounding, with such
determined concentration, the course and action of the flames,
wherever they may have spread.'^ The patentee also remarks
that the same sfecurity is likewise extremely applicable on board
of ships.
Olfseroations. — ^The great number of dreadful fires whif h hap-
pen in most large towns in this kingdom, and particularly iit
London and its vicinity, imparts to any mode of either prevent*
ing or readily suppressing them, a peculiar claim upon public at-^
tention. This mode certainly manifests considerable ingenuity,
and usefulness ; but we fear it will be attended with too much
expence to be generally adopted. The alarm alone, however
might be used in a variety of cases, at a small expence ; and would
be found extremely beneficial in procuring the means of extinction
while the fire was in an early stage ef its progrsss^ and con-
ttquently easily suppressed.
( Ui >
tfmm
Mr. JoHi^ Slater's Pateni for an Imprwpmeni in hanging aid
securing Gritiditpnes from breaking in the Middle or Centre,
Dated February f 1810.— i^prr^ory of Arts^ No* 99^ Seamd
Series*
In hts mode of effQCting what is expressed in the above title,
Mr. Slater cahses the grindstone to be hdng upon a spindle pass-
ing tltrough the centre in the usual way, except so far as relates
to tight wedging. Instead of this last operation, he plates a
circular and flat piece of wood of a convenient diameter ou each
tide of the grindstone ; and upon the outsides of these he places
two fiat rings of iron 6r other suitable metal ; and to these last
are added a pair of strong gripes or braieing plates vHh iron
screws. Each of these gripes is a ttrong cirtrular ^ate corre'^
iponding to the circular rings above-men tioned» aod has a proper
hole in its centre to receive the spindle of the griudstene ; and at
a proper distance from its circular edge ie^riml holes are made
at equal distances from each other to receive screws. The
bracing plates are then placed on the spindle of the grindstone,
And secured in their places by screws or cotters. The screws
which pass through thclm near their circular edge8> are then
(Screwed firmly against the iron rings, and by means of them and
the wooden circles beneath to secure the grindstone firmly be*
tween the apparatus on eadh side.
Obseroattont.^'^his method of hanging grindstones, though
Considerably more expensive than that usually adopted, which
as to wedge a plug of wood tight m the centre of the stone, and
a spindle axis in that, seems to be more than counterbalaoced
in the security it affords against breaking the stone, by driving
the wedges which fasten the wood and axis in the ceutrci and
against the subsequent effects of accidental moisture expanding
the wedglllr with still greater force ; and in preventing the grind*^
stone from working loose on its axis, either by the decaying of
the woqd^r the constant strain on its axis arising from its ro«
tary motion.
No. XXVL wUi bejpubUshed Ftd. I, 181 1.
Printed by Poplo and MiUeo O&d Boswdl Coort, Strand*
RETROSPECT
Of
PHILOSOPHICAL, MECHANICAL,
CHEMICAL AND AGRICULTURAL
DISCOVERIES.
^sammmammBsmmBmemmmmmmmmmmmmmmmmmmmmmmmammmmamB^
No. XX VL] October, N&vembeTy December. [1810.
AGRICULTURE.
Essays on AgricuHurdl Machmes ; contafmng
1. jfn Essay an the Mathematical constmction cf, a Plomghf %ohkh
shall offer the least resistance^ and which shaA tut9 a furrow m
the best manner.
!3. On combining ttuo^ three, and four of these pUmghs together, so as
to save one^fourth of the ordinary expence ofpicugking,
3. On the construction of a dynanometer for measuring the rdatto^-
resistances of ploughs,
4. On the construction of q newfashioifed Roller, and of a new set
of Harrows for harrqwing and rolling Com in the Sfringymui in
moist land without the horses treadifig it,
5« On breaking young Horses and Oxen to all kinds of Wfirk easily ,
safely, and expeditiously,
6. Off the comtructiqn of Wheel Carriages upon a new princiffe.
By Jtfr. William Amoi.— Com. p,qfJgric, vol, 6, part 2*
l^ a preface to the Essays the author gives an outline of the
history of the plough ; and states that about sixty or seventy
years ago one Lan^mis, a Scotchman, first attempted to establish
its construction upon mathematical principles^ he concealed the
discovery he had made i^nd obtained a patent for his implement*
A plo^ghwrigbt of the name of Plashley soon gained a knowledge
of these principles, whose 9on established a manufactory for these
ploughs at Rotherham, whence they obtained the name of the
iiptherham plough. At length the Amertcansj having obtained
a knowledge of these prlnc^plesy laid claim to th6 original invfn*
No. 26.— VOL, V14 ' *»
2 Mr* Anm^t Essays on AgruuUural Subjects.
tion^ and Mr. Jefferson, when presyent of the United States, pfe*
Rented tl^e principles for the construction of the mold-board, as a
new discovery of great utility, both \p the Institute of France aB4
the Board of Agriculture in England. These principles are
stated by the author of the essays under notice to have been
accidentally discovered by him.
In i\it first essay, on the mathematical construction of a plough,
the ^ttonlicm is^ cbii^fly caUed to the pohkboard. Tlllfe k cousin
dered as connposed of twb incliried planes ; one acting in a perpen-
dicular direction to raise the furrow, the other in a horizontal
direction W tiirii h over ^ and the perfection o( a plough is held to
depend upon the proper form of the curve, which a combination
of these inclined p\^hi .o^hlt f(\ m^ke. And as it is a known
property of the inclined plane, when the length and breadth are
giv£fl».ih^t the ^re4tex.the Length thejess isJthe powec f tbi^fore
{he longer the mold board in ploughs the ks^ is the fower reared
to raise the furrow. Yet Wl Amos insists that, for^en^f^ u^^a
pTdugtifrom Che sBare point to the heel should not excecdthirty-six,
nor should be ever less than thirty ^ ^^PV^ the average length will
be thirty three ; but this greatest length is to be preferred for all
stiff soils; and if 8 ioches he aIlpw«4.'fAi> the, solid part of the
share the mold board should be 27 + 3=?:30, the tiire^ inches
bc^ng added ti nhake the tail board longer kt the top than ai'the
bottom ; and tW height of the mold boatd* cannot be less ttiau
the breadth of the furrow, and upon brokeu land should be tjhre^
i9iTto or four incbcs higher. The width of {he plough sole should
not be less than the. breadth of the furrot?/, and the widtK at top
hearty double the width at bottom./ l^fom these preliminaries it
is supposed that the furrow be nine inches wide and six inches
deep ; and the length of the wooden part of the plough sqk 27
inbhei; and it is asserted that in this case tlie block of wood'tO
furnish the mold board must be twdVe inches widcj nine incheS>
high, ^nd ^thirty inches long, fof that if such a mold-board be
made to be pressed in' every point .^Hke," and to wear no mroreiii
one palt' than anotfeei', it will raige the fu^:row and turn k ayeir
\vith less power than any oth^ form. And in order to obtain
tbalt foritt, and the curve which a oombination offbetwo inclined
plaoBa <wghl: to^aaake, the perpendicular height ^d the hori2U)ntai
Width at toip isnist be equally divided by a dlil^iMfidl Ittie proceed,
ing from iht left hand lower corner of the fore part to the right
hand «ipper corner of the hind part ; and the advantages of such
a mold boanl ftre stilted to be, that the land is ploughed in the
best maimer fiossible, and with the least loss of power ; and that
the. furrows are so laid as to preseiK the greatest sur fat; e possible
to the influences of the sun and atmosphere, and to furnisli the
grcfileftt qu-ntity of mold for covering the ^eed.
This 4ir«ctioi}, wJuch id^ stated to be-in the power of aiiy com«
inoQ workman to follow <^fter haviog onee seea- it executed, is
<ienioiistrated to be €(>rre<;| by a long aerie^ of matiieniatical
deductions, assisted by diagrams, which it.ie impossible to- explain,
without tbe as;5istance of the plates . whiehr accompany th^ ^ri*
ginaj. , '
The second essay, on combining, ^wo, three, ami fmr ^ theit
jdonghs together^ fof fhugUng fwrtom nim hy feot inches gfuare,
stales the only consideration to be to bring them as near td tbe
horses as possible, so as jto preserve the true line of draughty and
to sbol'ten the length of the aole as much as consistently ran be
done. A profile and plan of a combination, of four of thesSe ploughs
are given, but it is almost, impossible to describe them without
.the assistance of tbe plate; but some idea of the mode may be
formed by conceiving the four beams to be framed parallel to
each other at proper distances, having the shares placed beliind
one another as in the common double plough ; and the distanced
of the beams may be regulated by screws ; the wliole machine
is moved by a swinging tree five feet and half long. Aad it ir
asserted that these ploughs will plough all kiftds of soils exrept
the strongest clays ; and that on soils of a tenacity next to clay
six horses will draw four ploughs, four borsee will draw tbriBe
ploughs, and three horses two ploughs, and on lighter soils eadi
horse will draw a plough. « >
The third ess&yf on t^e comtrudion of A d^mmometer, potivts ent^
that the. relative resistances of ploughs, or the weight required to
draw them forward, may be ascertained by a machine made lipott
the principles o§ a spring steel-yard, consisting of a i»dtal tube et
sheet iron nine or ten inches long, and tbiiee inches diameter
inside measure, in which is inclosed a spiral spring coiled* Ihrne
or four times ro.und, made of fine steel and of oonsidterfeble
strength, full half an inch diameter ; one end of this spring ift
fastened to the tube, and the swinging tree to the oliier form^
into a hook, and the degree of force is measured by a gradu^ned
scale on the hook ;. as in the common spring steeKyard*
The fourth essay is an the eoastruction of a new set of AatTBXoti
nnd a neui-fashioned roUer^ for rolling ^tmd barr&wing nvrnt land^
ivithoul the Worses treading it» The writer premises that when tho
ploughing is finished a considerable degree (^ dtifieulty frequently
attends putting the seed into the ground in moist seasons, and
on wet land ; and it is thought that these inconveniences may be
cb via ted by the harrows described in a plate, which are four small
barrows so constructed as to be ail connected to the same swing*
ing tree, and wide enough to extend from the ridge of one land td'
tbe ridge of the.next, so that the horses onlj walk in the furrows*
The roller is drawn in the same manner^ and .consists of -tbrefr
b2
/
4 Mr* Amoii Essays m j/griaikurtil Subfeitsm
partSy the middle part, which goes foremost, is formed of the
fnistrdms of two cones joined together at the larger end, so as to
fit the furrow, and the other two parts, which tnh placed farther
back, are two common cylinders.
The jytk essay, an the hreakmg of young horses and oxen to ail
Jmids of work f eaniy, stfely^ond expeditiously f^htSLtes that the writer
begins when they are weaned by swinging them in hand once
every day for two or three days in the foal yard, where they con-
tinue with the halters tied round their necks ; after which they
are tied up in an open hovel, while they are eating their proven,
der, and their feet are lifted up and they are accustomed to bear
hammering and other familiarities. Before they are wanting for
drawing they are placed in a stall, completely harnessed and
equipped with a cartF-saddle and a pair of traces, and a swing-
tree, to which is tied another trace, passing over a pulley fixed
in the wall, and having a four stone weight at the other end sus-
pended in such a manner that when the animal stands forward to
eat his com and hay, he shall carry the weight upon his shouU
ders, and when he falls back the weight shall rest upon the
ground. And in breaking young horses and bullocks to go in the
shafts, nothing more is held to be necessary than strapping a
cart saddle on their backs every day till they are perfectly quiet
with it.
In the sixth essay, on toheel carriages, it is observed that in
four.wheded carriages the fore wheels are made of a less size
* than the hind. ones, on account of turning, but that according to
mathematical demonstration, when the wheels are of the same
size, and their centers equal to the moving power, and that con*
seqoently a horse exerts the greatest power, when he draws in a
direction at right angles wiSi the inclination of his shoulder,
which is about 18 degrees; but as horses go one before another
in carts and waggons, the line of draught must therefore be a
medium between the shaft hoist, and the one before ; and as the
one before is supposed to draw at an angle of 10 degrees ; the
medium inclination of both their shouldei-s is taken at an angle
of 14 degrees. A variety of calculations are then added to ascer-
tain the proper height of the wheels, which are however unintel-
ligible without the plates to which they refer. And some valua-
ble observations are added on the constructions of wheels, and the
most advantageous mode of loadiug carts and waggons.
06t«rva<iW."— These essays evince in the writer a competent
knowledge of all the subjects treated on, and very considerable
acquirements in mathematics. They may be read with no small
• advantage both by the theorist and the practical workman. The
first and the last, on the construction of ploughs, and on whe^
Letter to Sir J^SmcbirfBart* , , "- ^/
earriAgeSy ai^e particularly deserviDg of attention, on acconntof
the importance of the subjects on which they treat. And we
must do the author the justice of admitting that these subjects
are treated with equal accuracy and perspicuity. The combina-
tion of ploughs is not a novel invention, and the new fashioned
barrows and rollers, and the dynanometer are more calculated for
the use of the curious,- than the practical farmer.
■■■■■I
A Letter to Sir John Sinclair, Bart, cfmtainmg a Statement of
the System 9 under vfhieh a eoneiderabh Farm nprtfitably managed
m Hertfordshire. By Thomas Gjibg, Esq.^'^om. Bdm of
Agril vol, 6p p, 2.
The letter commences by an acknowledgment of the informa-
tion obtained from Mr. Coke, of Holkham, artd t^ie Rev. Henry
Hills, of Suffolk ; and the writer then proceeds to describe tha
old system of husbandry in Hertfordshire, the existing leases
thefe mostly binding the tenants to a three years course. They
begin with a summer fallow, and to obtc^in tilth they plough four
and a half times for wheat and barley ; the first ploughing ia
performed as soon in the spring as the lent corn is put into the
ground, and repeated during the summer ; part of these fallows
is sown with wheat in the autumn upon narrow stitches, tha
remainder with barley in the spring. Sheep produce manure for
SO acres, the farm-yard only for 20 ; ]i|ht manure is purchased
for 20 acres, and about 20 usually go without. Iik the succeed-
ing spring, the wheat and barley stubbles are ploughed up, and
sown with either oats or peas without manure, and then the
course begins again, though sometimes turnips and grass seeds
are sown. To illustrate this, an account is given of the system
of management and expence of cultivating two hundred and forty
acres of heavy land by a Mr. Mickley, who was for fifty years a
tenant of the Earl of Hardwicke, the profits of which come out-
to be 321. 10s. Od. annually. The disadvantages of the old sys-
tem are stated — i. A plurality of ploughings, which expose the
land to be impoverished by a summer sun.-~2. The unneces-
' sary expences of these ploughings as they relate to labour.— 3.
The wear and tear ot horses, ploughs, &c. — 4. The rent .and<^
taxes of one year without return —5. The inefiiciency of sum-
mer ploughings to destroy weeds propagated by seed, twitch ex*
cepted. — 6. The deprivation of turnips to the amount of thirty
acres.— 7» The little stock they are enabhd to keep.-.-S. The de«
iiciency of manure arising therefrom, and the impoverished state
to which that little is reduced by bad management.. ..9. The
expence they are subject to in order to supply this deficiency.—
s9l 6n Spmg Crofiif "OiitAmti Sprmg Pbughmg.
lO. The d^tiency in -the crops of oats^ peas, and baana, wdi
lateness of spring ploughings occasions.— II. The abim^kuice of
annual weeds they raise within the influence of the air to vegetaie,
and the impossibility of cleaning those crc^s.
Mr. Greg, having established in his mind as a general princi-
ple that fertility was to be derived from puiveriaing the soil,
clearing it from water^ and keeping it clean ; he ploughs once
for a crop, and that in winter, and never fallows in summer ;
and he practices the ruw-culture, and borse-hoes at an eitpence
of 5s. 6dL per acre. He sets out his lands in uniform breadths^
and ploughs a dividing bout in each furrow to the depth of four
incites ; .his ploughing is performed by the SuiTolk swing plough,
and the Ume chosen is before Christmas, that the land may ac-
quire a perfect friability from the influence of the frost, and the
surface water is got rid of oy underdraining. When beans are
sown in the spring, the lands are much flattened and loosened at
bottom by a scarificator, which completely prepares the land for
seed. The course of cropping pursued is — 1. Turnips; 2. Bar-
ley or oats, sown with seeds for two years ; 3. Grass ; 4. Grass ;
5. Beans or peas ; 6. Wheat ; and as soon as this crop is har-
vested, the land is marked out anew, and a fresh course com-
mences ; and sometimes tares are sown to precede turnips, which
is held to be very practicable, and produces an abundance of
spring food. The grass leys are conducted upon a system of
giving half to the sheep early in the spring, and mowing the other
half, and the next spring the parts are changed. From a state-
ment off the expences and income of this system, the profit ap-
pears to be 6731. Is., per annum.
Observations. -^Ther^ cannot remain a doubt of the advantages
of Mr. Greg's system of husbandr}', oyer that usually pursued in
Hertfordshire, both to the farmer himself in point of individual
p*x)fit, and to the comniuuily in the increased quantity of pro-
duce ; and we had thought this had been tpo universally admitted
to have needed enforcement by the recommendation of the Board
of Agriculture.
Memorandum as to Spring Crops without Spring Ploughing ; alsQ
as to Jrable Land. By Mr. David Matnabd, of fVhittleS"
fordy near Cambridge, — Commun Board of jfgri^ voL 6. p, 2.
The writer states, that he has been in the habit for many
years back ,of sowing a great part of bis lands, without a Iresh
ploughing, the land having been ploughed in the autumn, or any-
time in the winter, when it could be ploughed dry ; and that he
Experiment bettoeen Spring Wheat and Barley. ^3
liad done this with complete success ; gaining, if not' in point of
isxtra crop, an opporlumty of getting his seed.into the ground in
due time, without extraordinary expence or trouble. And he
adds, that ttiany of his neighbours have been induced to follow
liis «]dii^ from a convic^ioif <^ i^e benefits lirisirig from it.
■>*iie ' ' ' ' *
OkserM^imiS.-^Tim mo^i powerful ^rgoncbenft iti fErrour of dny
new agricultural pm^tiqe^ is the ^t of itsihttviiig reconmiende^
itself to the unin&N-med) in ooo^eqiiesce. of thieir eofivinla<it 4»f hs
superior utility ; andoa tibi^ b^is resta our. iw^vke tX)tioHow, <m
all'Cd^mpatible 6oUs^ the plattof Mr* Alaynard.
,»> ,. t..
f ■ »>^
lapmment bttxpee* Spring Wheat and BsHef^ By Mr. Adaui
RuTHERroRD, »f .DomngtoH Terk.^^GoM^ Board qf Agn.
ml* 6, ». 2. ,. , ^ . - .
On theiSth of April, 1807, a few lands were sown with spring
^heat, and a few lipids contiguous to them with barley, in drilled
rows at 12 inches distance ; the wheat one and a half, and the
barley t^p bushels per acre ; the aoil of the whole was of a clay
loaa»)quaJ[ity above mediocrity ; both the wheat and the barley
were horse*hoed. the second week in May^ and frowa with grasil
seedy and then l|^ifj[owed. and roUed^ and both, were a foil erop
'ftn4 ripe t^gether^ On the 52d of September they were both
reaped, and , the^ produce of the wheati wai^ four quartern, of the
w^eigjiat of 6 lib* ^er bushel to tlbe aore, and one ton of ttraw ; of
the bark}! six quarterjs to the acre, and one ton three cwt. o#
sitraw* V^uing then the wheat at 72s. per quarter, and the bar*
Ic^ at 4^^ the wheat (f'rop.will have the advantage of the barley,
^pd tthe yalu^ of ihe< straw nearly, equal. The grass^ seeda among
^ wl^^Xt were n^ui^l) h?tter.thao thoae among the barley, which
is supposed to have arisen from the greater admittuftice of air into
the wheat crop, a msi^tter of great importance, and meriting the
attention of the far^^er*. .
ttmrnrnm
Ob»prtatio»s,-T'l^h\% experiment clearly ^hewft that spring wheat
may be cultivated with asi ainch profit to tk« fafrmer as barley ^
and that it is better adapted to the raising a crop of grass seeds
£^HaoBg the corn, iwt i& many instances the grass seeds are entirely
destroyed by a luxuriant crop of barley, where spring wheat might
be grown of greater value, and yet the seeds exposed to no risk.
Mr, Rutherftwd deserves well of the Agriculturist for the accu-
rftcy witli which kis experiment was conducted, and the plainness
\vith which the result is communicated to the world.
$6^
Oien and Mokusa. Bp £. T. Wateks, Efq.^'^Commumcatums t9
the Board of Agriculture^ vol. 6, p^ 2.
. The writer had two four-year old oxen, which went to grass
in May in the lowest condition, and remained there till the fiist
of October, when they were pat to hay and molasses ; their pro-
gress, from the moment they took to their food, was visible, and
they (^btained a prise at Lord Somerville's cattle shew in 1609.
OifervofioRi.— -The success of Mr. Waters proves that other
artificial foods, besides oil-cake, will fatten oxen, but we doubt
whether the meat will not be deteriorated by molasses.
On Swedish Turnips. By A. Bacon, Esq^'^Com. Board of
Jgri. voL 6, p, 2.
This communication gives the result of an experiment, which
the writer has reason to think will render late Swedish turnip
crops certain, and attended with little expence. * Having sown a
£eld three times, he did not succeed till the end of July, and the
plants were in rough leaf in August : thinking the crop would not
be of much value, as the turnips were not theh^ larger than wal-
nuts, be ordered some peas stubble to be ploughed up, and had all
the plants drawn, which could be spared with leaving the groimd
properly covered, and planted in the furrows of the new ploughed
land at six or eight inches apart, and they were ridged up by a
swing plough in September. Not a single plant failed, and the
crop was as abundant and as good, as in the field from wh^ce
the plants were taken*
Observations, — The success of this experiment cannot fail to
recoipmend the practice in those instances where early sown crops
accidentally fail, and where a supply is absolutely necessary for
the winter support of the stock on' the farm*
\
Experiments on weeding Broad^casf Crops, By Mr, John Wright^
of Pickworth, — Coni, Board of Agri. vol, 6, ]^, 2,
This paper is the result of an experiment on the produce of a
weeded and unweeded crop. One acre out of seven was left un«
weeded, and produced 18 bushels; the other six acrea were
On Courses of Crops, ani leeimgi 96S
trended at an expeoce of fire tHilUngs an acre, and produced*lS5
bushels, or 22| bushels per acre. The following year the expe.
riment was tried in two fields, ilnd gave similar result^ ; and was
also extended to barley and oats : the unweeded barley produced
33 bushels to the acre, xuidthe weeded part 28 bushels ; the dif-
ference in the oats was quite as great.
Obseroations.'^^These experiments fully evince the practical
advantage of weeding com clean, notwithstanding the speculative
doubts of some Agriculturists.
On Spring Wheat* By the Rev. Mr, MouirsEY, ofSproxton, near
Melton Mowbray^ Com. Bd. of J grit, toL 6. p. 2,
This gentleman began to sow spring wheat in 1801, and was
tolerably successful in the culture of it for four or five years ; but
in 180^ he found it much injured by the blight 6r mildew^ which
at first affected but a small part, but gradually extended itself in
nearly a circular direction, and became worse in proportion as
the com 9tood longer ; and upon enquiry among the neaghbounng"
farmers, he found that the same circumstance had before occurred*
He does not however think spring wheat more subject to this
disease than winter wheat*
- Observations.'^Titis communication is only deserving notice, ai
it shews that the very general opinion of spring wheat being .
exempt from the mildew, is not well founded.
49a Dramng, By Rd. Ramsdew BKwAlMLET, Esq, — Com. Board-
of Agric, vol.^, p. 2.
This paper is only an account of draining wet peat ground in
the county of York. The iraprovemsnt was conducted in ^he
usual manner, and the only circumstance which could entitle the
paper to publication, must have been the extent of the soil ini-'
proved, which w^as more than four thousand acres. . .
sss
99B
wmm
0« Courses of Cropsy and on Feeding. By VV. N. — Agric. Mag*
No. 39yarid4,l.
That part of thise papers which relates to the course of crops,
is an endeavour to draw a comparison between a seven year, and
gi four year course ; and the inferences of the writer are in favour
^f the latter. The rotation of the sevea years course is supposed
2>}o. 26,— VOL, VI. . 3 b
9€€ . On FmcJ B(rri^, 4c.
(q bf— X. WheM 5 $. BwltjF «»r €kf^ ; 3. Turni|i!fl| j *. B§i%; 5.
loLyer of ^e^s ; 6. The sfime £»r a second year ; and, 7* Peas.
lie fi^deavours to prove, that a four years course of alteroatf
gceei^L and white crops^ is botb les^ injurious to tlie Is^ and
more profitable to the farn^er ; since it is sure to produce a clean
fallow, and to supply an adeq.u^t£ proportion of manure &>r every
crop of corn. To mow clovtr twice the first year, and to feed it
off the second, he cx)nsider8 to be very hurttul to th^ Und, and to
be such an ei^couragemeot to the growth of qouch grass, that
nothing but a summer fallow can eradicate it ; and a variety of
calculations are added in confirmation of the opinions given.
The feeding clover the second year, is represented as an un-
economical mode of disposing of the produce, and at the s.ain^
wasting the manure dropped on the land, which is scorehed up
by the sun, and rendering the soil by treading time too hard to be
ploughed up at the proper season.
Ohservatiofu. — We had supposed that the doctrines contended
for in this paper, had been too generally admitted to have needed
farther argument. The opinions here given on the subject) are
very sound in themselves^ and are deserving the notice of every
fermer, who has not made up his mind upon the subject.
fifi H^acagontkl or French Barley^ and on the S^e^sk o^ naked Air-
ley. Btf Mr. C. W. S. V ag%t^ of Pangkowm^ Berks. ^^4^1^
Mag. -^o. 39.
, This person, in the month of November, transplanted twenty-
five roots of hexagonal barley, which had casually sprung up, at
a foot apart every way ; it stood the winter very well, never Ipok-
ing more sickly than wheat generally does, and in the spring it
put forth such an abundance of stems, as surprised every one who
saw it. It was kept clear of weeds, and cut on the ^9th of July,
^d the produce of the twenty-roots was 63,875 grains of barley,
and the straw was thr.ep fe^t six inches long^
Observations, — This accidental experiment certainly conveys a
'vw^rfavonrable opinion of ^he fertility^of French barl^, but the
produce of garden cplture cannot be expected to be equalled
in the common course of husbandry.
3.ir
On polled Cattle^ by the Keeper of a few Cows at Cheshunt, Hert$
Agric. Mag, No, 59*
Thb writer congmtulates the agricultural world on the great
increase of polled cattle within the last three or four years, and
recommends the extension of the practice as far as possible, be*
cause cows are extremely mischievous with their horns to one
another, and because among labouring beasts, it would be more
convenient to have them polled.
0&iervaftm«^— -We are at a loss to assign any other probable
causes fisr the publication of this article, than the desire of the
author to appear in print, and the scantiness of materials for this
number of the magazine*
Oh GMia^s knd Staggers m Sheep. By H. Gp-^Agric. Mag.
No. 40.
This paper is sent to the magazine for the purpose of diffusing'
a knowledge of ^ recipe for this disease, which was found in ap
old family receipt book, and the efficacy of which has been ascer-
tained by Uie writer. The receipt directs to *' take fat sij^
^* spoonfuls, fish oil the same, fuller's earth one pugil ; make*
^ water or chamber-lye as much as needeth, mustard seed three
** spoonfuls, marsh mallow roots gathered in the first night of
the new moon, one pugil ; and seethe the whole over a slow
fire ; you are to rub the bead and under the horns of the dunted
** (giddy) sheep three times, and (God willing), he will heal.''
it
Observations, — The insertion of this paper would almost induce
lis to suppose it an admission on the part of the Editor of the
Magazine that his publication is rather calculated for the perusal
of superstitious old women, than of farmers possessing general
knowledge and experience.
^9
On the use of Long Dung; by James BRiGHTLEr.— -^gnc. Mag.
No. 40.
An ill assortment of arguments in favour of long dung, selected
yfiih little judgement and less experience from a sufficient number
of publications to screen the writer from the charge oipartktdar
p ^giarism.
( ^6% y
1. On the celdn-ated Borin^ or Butter Grass.
2! On Fiorin Grass.-^^grie. Mag. No. 4» and 41.
Both these papers take notice of Dr. Riohardson's extravagant
ejicomiiims of the fiorin grassland admit its quality to be very-
good, as abounding in saccharine juice, and well relished by all
domestic animals. And though it is allowed to be more plentiful
in Ireland than here, yet it is not allowed to be a native of that
country, being found in wet soils, and the bottoms of ditches,
and under church walls, both in England and Wales ; being the
grass irequentljr called knot-grass; The authors of the two pa-
pers suspect that its value was appreelatcJ in a pecuharly dry
season ; and that it will not be equally esteecoed on an average
of years«
Observations. We are glad t© see that the fiorin is excitin^^
such general notice that its merits (whatever they may be) will
Bot rest on the opinion of one or two individuals, but will be as-
certained by the less precarious judgement; resulting from actual
experiments on different soils.
On the advantages offeidmg Horses with Steamed Potatoes in lieu of
Com^^-^Jgric. Mag. No. 41 . •
The mode in which the author steamed potatoes for his horses
was by suspending a tub with holes in the bottom over thfe cop-
per so as to be lowered or elevated by a rope over a pulley fast-
ened to the ceiling, and of such a si^e as that about fourteen in-
ches might go into the topper, the part being defined by a large
hotyp, and the quantity given to each horse was SSlbs. per day
with corti, or 561bs. without. The balance in favour of pota-
toes by feeding ten horses for half a yter is given at 1361. It is'
asserted that the horses looked equally well, and were equally .fit
for work, as when fed on corn and hay only.
Ohservations,-^The mode of steaming potatoes here described,
is simple in itself, and combines all the advantages of more ex-*
pensive apparatus, but the feeding horses upon this root aiokie,
without a reasonable mixture of corn, is a system which we can*
lH)t recommend, where they are kept to constant work, ■ • '
( ^9 y
On Smut in Wheat, By Mr* Batchelor, of Lidlingtm^ Bedford'
shire, — Agric^ Mag. No. 41,
From experiments made on little beds ndt a yard square in a
garden, cumpared with the observations of others, Mr. Batcbelor
tb: i'.s the foil owing axioms may. be fairly deduced; 1. That
sni'it is a disease peculiar to wheat; 2. That it shews evident
signs of Its originating at th^ root by its aflfecting many branches
of the »cime plant ; 3. T^at the infection is not irresistible be*
cause somt; of the ears, or corns in the ears often escape : 4*
That the same causes which preserve some of the ears, may
sometimes preserve the whole, though infected at the roots ; 5.
That peculiar seasons probably co-operate with, or prevent the
infection in a great measure ; 6. That if wheat be well blacked
with smutty dust, it is probable that only one fourth or one half
the produce will be smutty ; 7. That whether the cause of in-
fection be an insect or some peculiar principle of putridity, there
is much probability that quick lime, or any other caustic sub-
stance will destroy it, or that water may remove it entirely out
of the way ; 8. That lime may be often ineffectual by not com-
ing in contact with some particles of smut, or by its want of caus-
ticity ; 9* That steeping may be useless if the corn is previously
clean ; 10. That the infection may sometimes be in the land, or
carried with the man u ret
Observations, '--^These axioms are too trite and too commonly
received to render them worthy of any comment.
Machine for washing Potatoes and other esculent Roots for feeding
Cattle. Bj^Mr, W* hjAT^^^of Paddington^^^^Trans, Soc. Arts,
Vol. 97 >
Tins machine consists of astaved cylinder revolving in a trough
of water ^o slow as not to excite the centrifugal force ; and
this pari of the implement 13 admitted not to be new. But Mr.
Lester has added levers and 'aheels^ and fiHds them a gveat im-
provement, as a " boy therewith can do the work of two men,
without exposing himself to the dangerous effects of dabbling
in cold water." If the earth be particularly adhesive, it is re-
commended that the heads of a couple o( old birch brooms be put
into the cylinder.
$70 On Planihig Larch' Trees.
Obserdotions. We are not quite sure that we understand Mr:
Lester's description of his machine, though it is illustrated with
a plate ; but if we do, it is nothing more than the application of
the power of the lever to the common trundling C3^1inder used by
the potatoe dealers in London. We have no doubt but that this
ing$mous gentleman plumes himself on his humanity in protecting
the potatoe-washer from ^ the dangerous effects of dabbling in
cold water;" but if the gullability of John BuH were less than it
JM^ it wonld be maeh more dangerous to dabble in the manufae*
taring of QtM^tk implements of husbandry.
wmmmmmmBmoMBmmmtmmmmBmmmmm
On planting Larch Trees. By Johw C. Curwen, JB«jr. Af.P.—
Trans. Sdc. Arts^ Vol. t7.
The gold medal of the Society was adjudged to Mr. Curwen
fbr the plantations described in this paper. It consisted of a
tract of mountain land of about foiir hundred acres in the neigh<tf
Ibourhood of the Lake of Windermere, which, though surrounded
with a wall six feet high, would not have let as a sheep pasture
for half a crown an acre : and he thinks he underrates the va)u6
of the wood at sixty years growth, when he estimates it at fif-
teen shillings per acre annually, with compound interest. Of the
different kinds of fir, which may be planted in such a situation,
this writer gives the decided preference to l^rch trees ; and out of
one million two hundred and sixty nine thousand trees, of which
this plantation consists, above one half are larch trees^
In every instance>each species of trees is planted separate, which
is said to be an advantageous practice in all situations, particularly
when wood is exposed ; and the number is only three thousand to
an acfe, as the thinnings in such situations would not pay the la-
bour. As an encouragement for planting larches, Mr. Curwen
states that he possessed trees of this kind at Windermere of twenty
four years growth, which contain more than twenty-five feet, but
that these grew in iavoared sitdations.
tt^m
Odseroations.'^The spirit of planting which so generally pre-
vails in the northern parts of the kingdom, wili doubtless prove
of ineoneeivable jNibhc benefit in future times ; and Mr. Curwen's
example in this and every other branch of agricultural improve,
znent is highly meritorious in him, and deserving of iraitatiojei.
C VI
mmstfrnssim
]0esenptum ^ a niMod qfpackmg Pkmti and Tr^eg iatmied for
4xportatUn. By Mr. W. Salisbvbt> of Brgmpton^-^Trmis^
ce. ofJftif Vol.97.
This intelligent gardener having found great diffioulty in pacb*
ing trees and plants for exportation, attributed the principal
cause, why things of this nature did not succeed Hilong joumiesto
the packing heing liable to heat, if it became by any means
damp, whereby the contents were very much injured ; andif th«3^
were left entirely dry, the moisture of the trees became exhausted^
and they consequently died for want of nourishmeflty and th*
mode of pls^nting the articles in tubs was impracticable in muxf.
instances. To prevent these inconveniences, he made use in
packing his plants of the long white moss {sphagnum palusti'e of
Linnseus) which grows in abundance oU peat bogs, and when de*
cayed^ forms a part of that substance. It is said to differ mate.
rially from other vegetables in possessing the power of retaining
moisture in a wonderful degree, and at the same time not being
liable to fermentation in^ny situation, even when laid togeth^
in great quantities, and to preserve the power of affording mois-
ture and nutrimeut to plants when completely enveloped in it.
The manner in which Mr. Salisbury is accustomed to pack up
plants is thus described. When the moss is collected from the
bogs in which it grows, it should be pressed in order to drain out
as much moisture as possible, and having boxes prepared of suf-
ficient size for the young trees (which may in some instances be
shortened) he lays in the bottom of the box as much moss as'
when pressed with tbe feet remains of the thickness of four in-
ches ; then a layer of plants is put in, care being taken that the
shoots do not touch, and that the space of four inches be left round
the sides, and then another layer of moss about two inches thick,
and so on alternately till the box be filled with four inches of
moss at the top ; the package should be pressed down as tight
as possible with the foot, and the lid then nailed on. He advises
to select lor long journies such plants as ai*e small and healthy,
a,nd when they arrive at their destination to have them cut down
quite close, evtn to the second or third eye of the graft, and to
have thtm planted for a year in nursery beds five feet wide with
walks between them of two feet wide, so that they may for 4
time b« covered and sheltered from the severity of. the weather,
for tre^ of every description suffer so much from removal that.
372 On Planting Ash^ €md ctktr Foreit Trea^
unless the weather is particularly fayoorable, they do oot recover
it for some time even in their native climate, -and this modeis re.
commended both as to shade in hot climates, and shelter in cold ;
the covering to be removed when the temperature is moderate.
This method is stated to be far preferable to planting them out at
once where they are to remain, inasmuch as they may be watered
«nd taken care with of so much more facility.
Mr. Salisbury sent to the society a box of young trees packed
in this manner, which came out quite fresh an^ healthy after an
interval of six months, and were then planted in a nursery ; and
the whole, amounting to several hundreds, have grown equally
well, as they would have done if only transplanted from one part
to another ol^the same ground ; and he has sent packages to Bos-
ton in America, and received information that the plants all ar.
rived safe and done well, while some fruit trees sent to the same
gentleman packed in the usual way were spoiled, owing to the
heat of the hold of the vessel, in^ which aU the packages were
placed. Some packages made up in the same manner were also
•ent to Sierra Leone by order of the African Institution, which
arrived safe, and several African plants were returned in the same
moss and boxes ; aiid these African plants were also'equaily well'
preserved during their voyage to England, and are now growing
in a flourishing state in Mr. Salisbury's kothouse at Brompton.
Some of the moss was sent to Mr. Thompson, the chemist, to
be analyzed, and the conclusion drawn from the results was, that
it contains in its composition, besides the ordinary principles of
vegetables, a very small portion of gallic acid, and of tannin, some
sulphuric acid in an uucombined state^ mucilage, and extractive
matter.
Observations, — A mode of packing trees, so as to ensure their
arrival in distant parts of the world in an uninjured state^ has
long been a* desideratum among tbe makers of plantations. The
meSiod adopted by Mr. Salisbury has stood the test of experi-
ment in the most satisfactory manner, and may be resorted to
for packing trees and plants for long voyages, without any doubt
as to the preservation of the vegetative principle. -
On planting Jsh^ Ckesnut, Elnij and other Forest Trees. By W. M.
Thackeray, M. D. of Chester, — Trans. S§c. Arts^ Vol. 27.
The number of trees planted by this gentleman on the estates
ofa Mr. Jones, (to whom he is a guardian) in the counties of
Denbigh and Merioneth, between November 1804, and May
180S, was one million one hundred and thirty.three thousasd,
eight hundred and seventy-three. Among ihese^ almost «very
04 the L^aWindi ofCor^andndet> tn
Jt&nd ^ free cultivated in th»s - coaciry was introdaced, but the
predoiDinaace was giveu to oak and larch. The paper is accom?-
panied^wiiih proper certi^catee of the flaurishing state of the
plantatioQs, and of tihe repair o| the fences. The exertions oC
the planter were rewarded by the Society with the gold medal.
Oh»ervations, — The great extent of these plantations will in %
few years prove highly ornamental to a neighbourhood, whidi
has been much in want of timber, and there is no doubt but thaft
Mr. Jooes, when he arrives at middle life, will be truly grateful
for the benehcial exertiuns-of his guardian during his nunority»
NATUHAL PHILOSOPHY, ARTS, and MANUFACTURES^
On the Land Winds tf Coromandei, and thetr causes. By Wll.*
LiAM ROXBURGH, M. D. — T^ans. of the Medical Society of
London^ ' Vol, 1 . patt 1 •
Thb land winds on the coast of Coromandel are those which
are felt at a particular season of the year and time of the day ;;
and proceed from the Ghauts or western hills towards the Bay
of Bengal. In the more inland parts of the country they ar^
not subject to so much regularity. Neither the history noc
causes of these winds Dr. R. things has yet been satisfactorily
ej^plained. He therefore briefly enumerates the phenomena
which accompany their beginning and progress, and the effects by
which they ^re generally followed, shows that the most plausible
reason assigned for their great heat is not the true one ; and states,
what his observations have induced him to regard as the chief
source of this accumulated heat. .
About tbe end of March or the beginning of April, and neac
T^oon, whirlwinds hurry in various directions, but chiefly froml
\yest to east, tovyards the sea. Soon after these winds take place^
the ranges of hills are covered \yith clouds which becopie daily
darker and heavier until they dispharge themselves in torrents of
rain accompanied by thunder and lightning : after virhich the land
wind immediately sets in with its full violence. They generally
commence about the latter end of April or the beginning of May J
apd continue till the early part of Jufte^; during which perioa
tjieir daiiy continuance is from ten or ejevp^ in the morning , jo,
tl^ee or four in the afternoon. At tljis time t^e atmosphere iji'
gfner,^lly hazy an(^ thick, except' in th^e' evenings and pi^hts
when the sky is serene and clear, if the wind. does not does conti-
N©. ^6.— VOL. VI. 3c'
.i -
Z7^ flU Ue Lmid Winds if Coiamandi!.
nue all day. When the sun at its rising appears of a fle^y faif
and involved in mist, it portends a land-wind day; and the rise of
of the wind is almost always preceded by along calm, and imme-»
diately by a cloud of dust. Their daily violence is checked along
the coast, about two or three o'clock, by the prevalence of the
sea breeze, which extends its salutary influence to the distance
4f tea or twelve miles inland. The sea breeze dies gradually
away about sun-set, and is again perceptible at sun.rise. la
the high country, above the Ghauts, the east wind prevails in a
similar manner in the afternoon. *' Should the sea breeze fail,
as sometimes happens, the land wind decreases gradually until it
dies away in the beginning of the night, which, on account of its
calmness, is dismal to a degree ; next morning, a little motion of
the air is again perceptible; but at the usual time, the wind sets
in as strong and hot as the day before* Every thing we put
our hands upon is then distressing to the touch, which must be
the case when the temperature of the body i:r inferior to that of
tfyn atmosphere. This we experienced for almost a fortnight in
the year 17999 ^n the northern Circars, when the thermometer at
eight o'clock in the night stood at 118% and at noon at 112%
Shades, globes^ and, tumblers then very often crack and break to
pieces, and the wooden furniture warps and shrinks so much that
even the nails fall but of the doors, tables, &c. In their greatest
intensity, however yl have never seen the thermometer rise higher
than 1.13*9 ^iz* in the coolest part of the house, though some say
they have observed it at 130^ .". At this time, spontaneous
fires are seen at night, about the middle of the Ghauts, and the
fnountains in their vicinity. These the natives ascribe to the fric*
tion of the bam|^ops against each other, but Lieut. Kalter thinkf
that the corky bark of the edenanihera pavonia is often spontn-
seously inHamed; as he has found it reduced to charcoal, and
ileveral of these trees burnt down to the roots, though in an
insulated situation. The land winds aie noted for the dryness
they produce on both the face of the country and the animal
creation. ^This Sensation is particularly fe)t in the eyelids, and
probably occasions those inflammations of the eyes which are
prevalent at this season of the year. The continuance of these
winds caii$es pains in the bones, and a general lassilade, and their
sudden approach, especially at their first setting in, sometimes
destroys animal life instantaneously. The natives secure them.
ieWes against the effects of these winds only by shutting up their
houses, and bathing liiorning and eveniag. Europeans employ
wetted mats, made of straw or grass, and sometimes of the roots
of the watlie : and the evaporation is so great as to require
water to' be constantly thrown upon them, in order to produce
(hi desired elTecc of cooling a small room, frequent showers of
On the Land f Finds of 0>romandtL 37 i
^rain generally terminate the violence of these winds in June, and
the Ghauts become clearer and visible at a greater distance than
they had been al any former period of the year.
I'be extraordinary beat which distinguishes t>)ese winds has
generally been ascribed ** to the absorption of caloric in their pas-
sage over an extensive tract of country, at a tmie when th« sun
acts most powerfully in our latitudes :" but this. Dr. R. asserts,
is not the true cause. According to this theoiy, this heat should
increase in proportion to the space over which this wind is to
travel ; but this is found contrary to experience. It should also
increase by its continuance ; but it is well known that these winds
set in with the greatest heat and violence at once, and rather
abate than increase afterwards. The heat should likewise in-
crease gradually with the return of the sun to those latitudes in
his progress towards the equator; but this is not the case; for
they ceafte altogether before his return to the 7.enith of these'
coasts. A material alteration in the temperature of this cli*
mate, however, is caused by the approach of the sun from th«
f&outh, but the heat is different from that of the land winds.
Winds of equal heat with those of periodical duration are felt at
different times in all parts of the country ; a circumstance of
itself sufficient to overthrow this theory. Of these Mr. R. gives
several instances. It has been asserted that the heat is gene-
rated by the concentrated and reflected rays of the sun in the
valleys of the Ghauts ; but Mr. R. contends that the sudden ap-
pearance, the usual strength, and the abrupt disappearance of
these winds militate against this opinion.
After having thus shewn wh-At cannot be the cause of heat in
the land winds on the coast of Coromandel, Mr. R. proceeds to
pbint out a theory which he conctives is founded on a firmer ba«
sis, and wil] explain the phenomena in a wore satisfactory man-
lier. This depends upon a chemical principle, and is regarded as
an axiom ; viz. " that all bodies when they become more dense,
sufler heat to escape ; or, what is the same, they give out heat."
It is k^own that £^ considerable quantity of heat is required for
the evaporation of a pound of water, s^nd it is but reasonable to
^drpit ths^t th^ S£^me quantity that it had imbibed should be again
released on returning to its former state of fluidity He then
observes that, *' in order to apply this principle to explain the pre.
sence of heat in our land winds, I must first observe, that the at-
mosphere in January, February, and March is perfectly clear
and serene; and then I call to mind what has 'leen said ^l the
phenomena of these winds, that they are preceded by clouds and
rain among the Ghauts, and that a heavy shviwjr of rain from
that quarter announces their arrival; that dnr.r.g their contu
npance^ clouds ^e observed to lie on tlie GhautSi and that tba
«
S76 On the Land Winds ^f CoromandtL
etmospbere, even in the low country, is hazy and thick. I muit
also add, that the countries west of thesGhauts are at this season
frequently visited by heavy showers of rain, accompanied with
aiucb thunder and lightning, and sometimes with bail. Here in
the Mysore country, I have found the heaviest showers of this
kind to come from the north-west, which is exactly in the
direction of the countries remarkable for. the great heat of i\m
land winds in this season." After another observation of less
importance, he adds, " By this, we see, thMt the clouds form^
on the Ghauts, charged with water and electricity, (by causes 1
am not now to investigate* ^^^ <^rawn to the westward, whilst the
heat which, during th© formation of these clouds, must neces-
■rarily be discharged, is carried to the east, or to the lower parts
of the coast, and causes the properties for which the kind winds
*re so remarkable." After some further observations, either iH
elucidation of his theory, or in answer to objections that might
be urged against it, Mr. R. concludes, by stating it as his opiniojn
•* that both the siroces and samiel may "be owing to similar
eanses to those which appear to be productive of the pernicious or
■TBthcr disagreeable effects of our land winds.
ObsfrvoHons* — ^The subject of this paper is deservedly rankrti
*ftmong the curious phenomena of nature, and merits the atten-
tion' of the natural philosopher; but the minds of those Europe-
ans who have visited these regions have generally been occu-
pied with pursuits very different from philosophic research. Hence
has arisen an imperfect acquaintance with the causes of this as
'Well as many other natural phenomena, the jtffccts of which have,
rendered them familiar to the inhabitants of the east. Mr. R.,
we think, has now offered the most satisfactory explanation of
those winds which we have yet seen ; and we apprehend that the
'itetne chemical principle may be allowed a much greater latitude
in the explanation of changes in atmospheric temperature thaK
is generally admitted. The EarFof Dundonald has, we think,
justly remarked that " the frequent changes in the degree 6f
*heiit and cold in the atmosphere are to be ascribed more to the
'alternate disengagement and fixation of heat by chemical com*
'bination, than to the effects of the solar rays."
««■■
Remarks on a new Prhicipk introduced hy Ltgendre in his Elements
of Geometry, by Mr, Thomas Knight. — Phd. Journ, No. J 24,
This new mode of i^casoning introduced by Legendre, and
considered as fallacious by Mr, Knight, is founded on the cohsi«
Kemarh on a nea> Vrincip!^ introduced mt(y Geometry. STf
deration of functions, and the homogenity of quantities. In
order to prove the fallacy of thi$ kind of reasoning, Mr. K«
gives the following theorem, which differs from the first of Le«
.gendre's only in his having changed angles, into sides, and the
side into an angle.
" ^Theorem, If two sides of one triangle are eqnal respectively
to two sides of another, th« third sides also are equ£^I.
For let A and B be two sides of a triangle, p the included
angle, C the opposite side. If A, B, and;i be given; <^ will
•evidently be completely determined. C therefore is ^ functioo of
A, B, and j9. But it is plain that/> cannot enter into this fuse-
•tiop ; for let some line, as D, be represented by unity: then A,
B, and C, are lAimbers, and if there conld be an equatimi be^
tween A, B, C, and;p, we might find p in terms of A, B, and O;
^whence/; would be a number, which is absurd. \i follows from
tiiis, 4;hat C is a function of A and B only ; whence the troth 4f
the proposition is -manifest. Q. E. D. — It is needless to 619,
that the principle must be erroneous, which leads to such li
'Conclusion.''
After some remarks relative to things that cannot be compared
iK)t being dependent of each other, and the use of Che woni
function in the preceding theorem, Mr Knight observes, '* It is
of tfo use therefore, to have shown, that there can. be no equa-
tion, properly so called, as C:r^ (A, B, p) between A, B, C, j>,
unless it could farther be proved that there can be no analogy 4n
C^9 OC, -^ (A, B^ p,) between the same quantities." This he coH-
xeives is not to bedone, since, in any sector of a circle the angle
•at the center is a function of the arc and the radius; or tkto
jL OC,'arc «&. radius ; which is no equation independent of an*aiw
-bitrary choice of units.
' ■'
06«^rr<?^ton«.—- Legendre, in his valuable book on geometry, b«i
sometimes deviated from the true geometrical spirit ; andtke
instance here referred to is one of the most flagrant, in which he
'^demonstrates from the consideration of functions and equations,
that the sum of the three angles of every triangle is equal to two
right angles. This method has not been without its admirers
among our cotemporaries, though it is tedious, obscure, and
unsatisfactory; and we think that Mr. Knight has shewn Ihd
absurclitjr that must result from its general application*
( 378 )
Account of ttnerw Method of increasing the charging Capacity^
Electrical Jars^ discovered by John WiNCi field, Esq.^—By
Mr, John Cuthbertbon, fkU Joum. No. 123; and FhU.
Mag. Nq, 150. '
Mr. Cuthbertsan has previously mentioned that breathing intp
electrical jars increased their charging capacity ; but in larg^
batteries this is inconvenient, and wetting them with water is
ineffectual. Putting wet sponges into theo^ as well as greasing
or oiling the uncoated part had also been tried for effecting th*
s^me purpose, but all gave unsatisfactoory results. Mr. Wing-
Held, therefore, pasted paper on bcah the inside and the out of
the coated jars, and found that it prevented them from exploding
to the outside coating, and be thought that it likewise increased
. their charging capacity*
This circumstance being communicated to Mr. Cuthbertsoi^
be iastitated a series of experiments for proving its truth ; and
after carefully repeating 25 of these, he draws from them t^
following general conclusions.
** That paper rings pasted on electrical jars not only prevent
them from exploding to the outside coating before they have re*
ceived their highest charge, but that they likewise increase their
charging capacity ; and that one ring pasted on ii^ the ineide only
is sufficient, if it is one inch broad ; ope half of the brefidth
must be pasted upon the coating, and the other upon the uncoated
part.*' Mr. C. also concludes his commuoicatiou by ti^ suc-
ceeding sentence. ^' Farther experiment^ and observations^ sev
ting forth the advantages that electricians may obtain from the
•hove discoveiy» with an account of some experiments made with
a view to prevent the jars from being perforated by bigk charges,
without increasing their thickness, wherein 1 am in h^pes I
shall succeed, will be the subject of a future paper."
Obsercations. — Any remarks of ours on this bead^ prior to the
publication of the pap^r promised in the last sentence would qf
course be premature.
Demonstration ofacwrims numerical Proposition*-^By Mr. P. Bar-
row.—P^i/. Joum. No^ 123.
The proposition which is the subject of the present essay is
this : that no power but the square can be either the som or 4jlU
' 'Jhmanitratimdf a curiam n&iericat PropoitHm. S7^
f€!ren<te of iwo other, powers of the sam* denominatioo ; or jr"+
y^zzz"" is always impossible either in integers ot fractions for every
vaHie of H greater than 2. *
Previous* to his entering upon the general demonstration of
this proposition, Mr. B. makes a fffw observations on the gelieral
equation, and states a few lemmas, in order to render it as simple
and concise as possible ; and, us both the nature of the essay and
the limits of onr work prevent us from entering into amy detail
on the subject, we shall merely state the observations j iemmaSy and
propositions ; either referring to the original for the demons tiations,
or leaving them to be supplied by the learned itigenuity of our
mathematical readers. i«.i«i.i»..-..
Observations. — rl. In demonstrating the impossibility of the
equation x" -f y"=«% it will be sufficient to considern as a prime
number* We may always suppose x^ i/, aod[ z^ prime to each
other ; for it is evident that two of these numbers cannot contain
a common divisor, unless the third contain the same. 3. It will
be snfficieni; to consider the ambiguous sign -f under either of
its forms -f or — : for if the equation a"+ y'*=: z" be impossible^
soisx* — y^zzx^; and if the equation be impossible under tho
latter form it is also the same under the former. Mr. Bariow,
therefore, confines his demonstration to the equation *■— y^zz x",
in wnichff is considered as a prime number, andjr, y, andjr; at
being prime to each other, since the impossibility of this equa-
tion, involves the impossibility of the general equation, stated
in the proposition.
a b ^
Lettimas. 1. If there be two fractions, as — - and-=-, each in
A i>
Us 'lowest terms, the denominator oFthe one containhig any
factor that is not common to the denominator of the other, then
neither the sum nor difference of these two fractions can be an
integer number. it» If any power of a number A, as A% br
divisable once by any other number r, and after that» neither by
r, nor any factor of r, then r will be a complete nth power.
3. In the expanded form of the binomial (p+gTf when n is a
firinie numb^, each of the coefficients except those of the first .
and last terms, is divisable by n.
Propaniions* i. If the equation «"'*y"=e*^ be possible, then •
one of the: four following conditions must obtain ; viz.
' rx — ^y=:r* rjr— ^rrn""** r*
1st. ^jr— «=i«^ «nd. -JjT— z=*'^
tx+z=^f C^+z=t"
£1^-^=1^* rjp— 5f=r*
9d. ^JT— z=2ii"-»«» 4th. <x^x^^
Cjf+z=<* (^+z=n'»-*l*
9SO Second nMUaiian if Dr. Berseiefs iiiwy (f eotouted ri/(g$4
2» The.cqi]»tJei^j:^^5»''=:2" tt impwttblc in uitegei% il being'
ahy prime number, greater than 2.
Mr. B. also prote^ that this equation is likewise icpp^ssible
in fractiuM*
< I - lull
. O^^cnaa/ioia,— Mr. Barlow observea that " this theorem is one
of the most interesting in the theory of numbers « both on ao.
count oi its simplicity aiid generality, and the celebrity of tb^ ,
mathematicians who have attempted its demonstration. .
It was first proposed by. Fermat as a challenge to the English
nathemuticians of his time; and it appears from a note. in bia;
edition of Diophantus that he had demonstrated it» though he
did not publish his demonstration. Eqler, we believe, was the
next who attempted a demonstration ; and he succeeded in the
cases where nrr3 and nrr4. Waring, in hisr Meditathnes jflge^'
htncWf and LegQndre, in his Tkiork dct Nan^ra hav« botlt wom
ceeded in proving the same thing; but we are not aoquaiBte4k
With any author who l>ad shown the impeesibidity of the foniMd»
fyr higher numbers. We have before had to notice Mr» Barlow^s
spcoesa ia the treatment of analytical subjects ; and we do not
i^w hesitate to state ii as our opinion that he has been equally
spccessf^l .ii%.de(BOA8tratii)g this th^eoiem generally. We must,
l^oweveir,.ieiD9fl( that hi» demonstration is neither 9Q> short nor
aa simple as c^qld be wished ', and the circumstance of JTermat^
who Aouriah^d ^boat a century and a half 4go, h^ving^ been i^.
ppssession of a 4emi^Bstrati^y appears to indicate that it is pos**
sible to obtain it in a more elementary manner* since the theory
of numbers has made considerable progress since his time.
» • r
SkeoMd mdiattioH of Dr. Hx&schel's theory of coloured ringSf im
rnnfer to «» wonymoiu Re^iqf>erj'^Fh%L Mag., No. lA^^
' Tub ^ menders of the* club*' whose forftier communication was*
** M fntich held tsp to vfew -by appearing in'* Mr. Tilioth's ^ excelr
l«nt-piiilmo|ihi4^*ttl misceHairf,^ that we ^'^tbc ReCraspcictore^' have
tl^ught it necessary to strike to it!* etili insist in this second,
vindication, that the wedge of air» which they describe,' was iy»
'oiber thMi the^vfedge of at riieaefibail' by Did. Herschei, alti^tiagb
they have noade no reply wbs^ver- to our reasons for Mieviagfi
that the wedge waa in. reality of very different dimensions fron>
those which Dr. Herschel attributed to it; unless we:censider
their remark that we " did jpot challenge" his mtasm-es " before,*^
as a reply to theaUack which we did makey not on his actual
measurement, but on 4ha competency of his zaode of'^p^easuung
Vindkaticin of Dr, itcrschfs theary of coloured rings. 381
and calculating, wfiich was not so detailed as to require a particu-
'lai-' examination, until the eagernefes of the " club" to undertake
his. cause brought it into a more prominent point of view*
They proceed to state a supposed contradiction in our state-
ment of the wedge having been too thick to produce the colours,
while the " bow streaks" are produced, as they imagine we assert,
in consequtTice of the great thickness of the plate by which they
are exliibited. They proceed to state, that we have denied, m
page 412, that the critical separation is capable of producing the
bows attributed to it by Newton himself; and they worthily and
wisely ccmclude, that " both attacks of the Retrospectors abound
-with similar inconsistencies and contradictions, which" they
' '^ think wholly undeserving of notice ; as with such opponents
we consider further discussions to be vain."
Ohserrathns -^The truth of the last remark we should not he
disposed to dispute, if oar modesty did not make it desirous for
ns to admit it with some hesitation, *' that with such opponents
as ourselves all further discussion would be vain."
We never said, nor could we possibly have said, that the
" bow streaks" were exhibited in consequence of the great thidc-
ness of the plate of air ; but we said that in consequence of its
grtat thickness they could only be exhibited in the case of the
very great obliquity of the light passing through it; (p. 410,
411,) and we never denied, for we never doubted, nor do we
know of any reasonable optician who ever doubted, unless We
choose to call Mr. Brougham a reasonable optician, that the
bows described by Newton were produced by the " critical sepa*
ration' exactly in the way that Newton supposed.
Haying removed these misconceptiort^ of our assertiMi^, wc
should proceed to reply to the remaining arguments contained in
the paper : but unfortunately the authors have reserved all their
other arguments for antagonists better calculated ta enter the
lists wit!) them; and we are not disposed to be/ ungrateful for
tlieir forbearance.
' T"
ji physical View of the Equatorial Regions^ from the tenth degree,
of J^orik to the tenth degree of South Latitude, drawn up from
measuf-cs taken and Observations made on the Spot, detween the
years 1798, and 1804. By Mr. Von Humboldt.— M^azin
Encyclopedique, Sept, 180/.
The author has here given a collective view of the natural
phenomena of the regions near the equator, from the level of tk«
. >»o. 26»— VOL. Yx. 3d
\
Pacific Oc6an to the highest summits of the Andes. He has not
extended bis sumniary nearer the tropics than the lOth degree of
Sttitude, on account of the ditference both in the productions of
.the soil and the /neteorologicul phenomena obseryed between the
. JOtfa and the 123d degree of latitude. From the western shore of
this part of Anierica, a plain stretches for a considerable extent
•from north to south, but in no .part exceeding ^0 or 30 leagues
• in breadth. The loftiest summit of this vast chain is Chimbo-^
2 1020, which rises in 1° 2/^ of south latitude. From the author's
: barouQetrical measurement, calculated by the formula of La.
place, the height was ascertained to be 7il43 yards above the level
. of the sea. ibis is 1 97 yards more than iM. Condamine's mea-
surement; but this is accounted for by the latter philosopher
having neglected the temperature of the air when his observations
were ^ade. In the map acompanying his work, Mr.^ H. has
given a vertical plan of Chimborazo, with the summit of Coto-
paxi appearing behind it. Ihis latter is nearly five times as
high as Vesuvius ; and the roarings of its volcano are said to
have been heard in 1744, at the distance of 220 leagues. This
traveller, contrary to the general opinion, iouud the east side of
the Andes to be much steeper than the west. Mr. Humboldt's
observations on the geography of plants exhibits several new
views; he has ascertained the different altitudes at which they
grow on the Andes, and noted the height they attain according
to the different situations and elevations where they are produced :
he has also given a comparison between the plants Iq those
regions and those growing at the same heights on the Alps and
Pyrenees.
It also appears that the cold of the Andes is not very consi-
derable, but many circumstances combine to render it difiicult to
bear. On Chimborazo, at the height of 6,457 yards, the ther-
iDometer descends only to 28.7fr° of Fahrenheit. In the hottest
regions on the brinks of the Amazons, Magdalena, and other ri*
vers, the mean temperature is 80.6° of Tab. ; while the heat
seldom attains the extreme experFenced in the north of Europe.
in the equatorial regions, the difference between the greatest and
east heat does not exceed 36" ; while in Europe this diflerence is
sometimes more than 81^. Th^ temperaiure of the Cordilleras
was found to decrease more rapidly as the elevation increased ;
and it is'stated that the proportion of this decrease above 3,825
yards elevation is to that bqtNVeen the level of the sea and 2,7 3S
yards in altitude, as 5 to 3 : and it is remarked- that tbe ine-
qualities of the surface have very great influence on this decrease,
and that a pefson going to the same heights in a balloon would
obtain difl'eretit results. Mr. Humboldt ascended Chimborazo ,to
jiucii a h«i^ht that tka barometer fsU to 14r64 inches ; the height
A fh^skal Fle0 f^ tie EjinUanal Rr^aat, ' 863
at the level uf the sea was 29*9S inches, apd the lenipeTatore
/ 77** "f Fabr. Booguer ascrnded it at 29*9* inclres when similarly
situated. The eKuiicity oi' the air in the temperate zone some*
times varies 1*77 mches in the same place; bnt at the sea sid*
near the tropics it on!y varies aboot 1*0t3 French lines. Mr.
Humboldt has given a table of these variations for the different
hours of the day at which they were cibservcdi. These horary
variations are not noticed in oar climate, on acconnt of local
causes which render them subject to so much irregularity. These '
barometrical researches are concluded with some physiological
observations relative to the connection between the elasticity of
the air and respiration; and he states that the inhabitants of the
plains, accustomed to a pressure of 29*34 inches English, easily
habituate themselves to the pressure at Quito, which answers to
20*4 inches; and even to other places still' higher where the '
barometer falls to 18*47 inches.
In his hygrometical observations, Mr. H. sometimes used *
Saussure's hygrometer, at others Mr. De Luc's; hut he reduced '
his results,' afttfr correctitig them fcwr temperaltire to degrees, of'
Saussure's* On the sgmmit.oftbe Andes, tlie hydrometer fell to '
^^7®+, biit there still remained considerable moisture ; which
w^s manifested by the freshness of vegetation." The aqueous '
Vapour which exhibits itself in large masses or donds, appeared '
t6 retain neai^y a constant height; the lower stratum being
afeut 3 ,277 yards, and the u|>f>er stratum near 3,606 yards above *
the level 6f the sc:t. Those small light clouds generally termed
rtocks frequently exceed 8,520 yards in height. Mr. H. estimates
the anantity of rain which tails between the tropics annually at
74'3d inches, ^
Mr. Humboldt's elettrometrical tables also, exhibits scleral
ciitious results. The atmosphe e of the equatorial regions from
the sea to above tlie height of the lower stratum of clouds is
only slightly charged with the electric fluid: it accumulates,
however, in the clouds, and this causes frequent explosions. The .
violence of these explosions is well known, and they recur pe-»
riodically, generally about two hours after noou. At the height '
of about 3,280 yards, great quantities ot hail are formed, and the
atmosphere is generally in a state of negative electricity* Mr.
M. thought that the bloeness ^of the sky was more intense be^
tween the tropics than at equal heights in florope; and this he
ascribes to the more complete solution of the vapours in the
equatorial atn^osphere. On the Andes, the blueness was 46** of
Saussure's cyanometer.
The decrease of light is .proportional to the density of the air,
ai>d therefore is much less on the summits of high mountain)
than in lower districts* In general, th^ light i« modh ^trooginr
-/
384 A physical View cfthe Equatorial Regions •
between the tropics than at equal heights in Europe ; as is proved
by the light reflected from the moon to the earth in a total
eclipse. I'he intensity of, light probably arts on vegetables, and
contributes to that resinous and aromatic nature which is pecu-
liar to those on the tops of mountains. It is thought, too, to
have some influence on the nerves, as the inhabitants of Quito
experience a sensation of faintness when the sun's rays dart upon
tliem.
Bouguer calculated that the atmosphere reduced to the tem-
perature of 32*^ of Fahrenheit's thermometer throughout its whole
extent, and to a column of mercury of '29' 9 inches, would not be
quite five miles in height; but the observations on twilight shew
tl^at the air has sufficient density to transmit a perceptible light
B.\t the height of more than 37 miles. Mr. Humboldt gives some
experiments made on the chemical composition of the atmos*
pjjcre; from which it appears that the component ' parts of the
aji* are 0*210 of oxygen gas, 0*787 of nitrogen, and 0*003 of car-r.
hpTiic 4cid gas. Gaylurssac found the same in air •btained at the
h/.igljt of 7,650. ya/ds,
^ In the interesting series of geological observations, it is oh"
iB^ved that the equatorial regions present both the loftiest sum*
mits and the most extensive plains, and therefore the origin of
tnese mountain^ cannot be ascribed to the rotary motion of the
g]ob&; and more especially as the chain of the Andes extend to
60 or ^jO degrees of north and south latitude. The height of
t^is chiiin is very unequal : in many places, it is not above 220
y^rds high ; while in four places it attains a vast elevation ; these
are in 17*^ of south latitude, at the equator in the kingdom of
QuitvO, at IMexico, in 19° n»)rth latitude, and near the 6oth de-
^,ee of n<»rth latitude. This height varies from about 5460 to
6p6Q yards. The chain of the Andes is equally as astonishing
on account of Us magnitude as its height. Near ihe volcano of
Antisana, Mr. H. found a plain twelve leagues in circuit, and a-
bput 4370 yards above the level of the sea. Some parts of this
chain are from forty to sixty leagues in breadth. Chimborazo
constitutes an extremity of a colossal group; and the range that
extends to the south stretches so far towards the ocean that the
inlands near the shore may be regarded as detached fragments of
it. On the north, the Cordillera forms three distinct branches :
that on the east.contains the groups of Santa Martha and ]Me-
rida. There is like^vise an extensive group in the western chain,
near Mexico, some of the summits of which, as Popocatcpeco
and Aribaza, exceed 6,790 yards in height. This is the branch
which furnishes platina. The height of this chain considerably
diminishes on proceeding noi^thward ; but in the vicinity of Asia,
if forms a fourth group, about 60 degrees of ngrih latitude, i*
A physical View of the Equatorial Regwu* : 3iS *
Which Mount St. Elias is 6,094 yards high. In these rRgkms, :
tiie Andes are supposed to have a suhterranean commotiicataon*'
with the volcanoes of Kamtschatka.
T,he internal structure of the mountains at the equator ma*' .
braces almost every kind of rock discovered in the rest of the-
globe; and the arrangement of tne strata is likewise perfectly
similar; But a circumstance 'p'^tftlliar to these mountains is the
vast height to which the rocks of subsequent formation to gra-
liite ascend. This biise is almost wholly covervd with tHe^e
more recent formations ; and the greatest height at wliicfa Mr*
H. observed it was 3,825 yards. The summits of Chimtxp-
razo, Antisana, &c. consist of porphyry, at an elevation of
about 6,960 yards. The remains' of organic bodies are very
r^re in the equatorial mountains ; and calcareous stones £|re far
from being abundant ; some were found, however^ at the height -
of about 4,700 yards. Fossil bones of elephants were aisb coI«
lee ted at an elevation of near 3,280 yards. Great masses of
sulphur were frequently met with in primitive rocks, at a die*
tance from volcanoes. The greatest number of volcanoes it
found in the chain of the Andes : where there are more than 50
between Cape Horn and Mount St. Elias, that still eniit flames.
Some of them throw out lava ; others, as those in the regions
near Quito, eject scorified rocks, water, and clay. Thse mo>8t
recent of the American volcanoes is that of Jesallo ; the air
collected at the bottom of this crater contained more than 6*05
of carbonic acid.
Amonjg the most constant of natural phenomena is the lomrer
limit of snow in the regions near the equator. From various
measures which Mr, Humboldt took; he fixes it at the elevation
of 5240 yards. The Andes have no glaciers, which is accounted-
for from the small quantity of snow that falls between the tn»pics ;
but on digging into the earth at Chimborazo, snow of great anfti-
quity is fouad.
Mr. H. in his description of the zoology of the Andes^ notes
the heights at which difierent animals are found. In his article
on the culture and produce of the soil, he also follows the
same plan. Several villages on the Andes are situated at a con<«
siderable height. From the level of the sea to the height of
about 1090 yards, the plantain, maize, and chocolate nut are
cultivated : thie is also' the region of the most delicious fruits.
The Europeans have introduced otlher plants ; among which are
the sugar cane, indigo, and the coffee tree : the last arrives at \he
greatest perfection in a high and strong soil. Wheat grows in
great abundance in Quito and Peru, between the elevations of
1750 and 2030 yards. The extensive plains of the Cordillera
»re particularly favourable to European grain : and the circum*
58fi : Humboldt J Phr^kahVka^ of^ the EqtutHirial Rcg^ovs.
•t^ocepf the feoil yielding easily, to th© plough, Lmluced Mr, lU^
fa sbppose that they weir^ once t;hc bottoma of lakes^ J^rom the
height af about 4280 yards to that of 4370, potatoes aire the
cbiei article <»f- culture. .AUav^^this regiou. the iiibabitants live
aoiotig their nutfierouis Qociss of laaias^, which of teu^ wander to th«
legioB of snaw.
»t*w>"^"**
"O^rrrarfiiwwv— The pi'eceding sonamary* relative to regions s^
distant and so different; fr^irour own, will.be interesting to every'
loiwr of geogra|>hical and physical science^; bui.itis^tead of satis^
lying it vriil only serve to excite his curiosity^^ and increase his
desires of ptrosing the hu)re detailed accounlg^veb by the same
atcoHipIisbed aulhor» in bi^ **. Tableau Phj^xifu'c.'dcs Regiom Bqua^
imak^ SpC** The nainiB o^ IJumboldt^ now stands brgb in 'the lislfe
of modern travellers ; and tp this pre-eoiineice Ke seems to he
jostly entitled by.his knowlo^ge, his zeal and perseverance ia this
ju'dttous Yindejrtakingv and certainly by hi$ success- 'j^be' vast majsa»'
of- cvriottft- and interesting information, respecting re^^ioii^ that>
'wetebei6|:e so -very iaiperfectly known, which he lias procined!
io-lhoeit distant travels, and the collections. /lie Has made relative
t8i vamus branches of science, much excee(^ any that had been!
cri^tained by the indefatigable exertions of' any preceding traveller.*
Ilhe physical and political geography of these reg ons have becri)
' Sreiady iariproved ; and the stores of botany, zoology, and riiine- '
lalogy, enriched with vast additions; which, class ed"^ under api-
propelai^ h^ads, Mr. H. is now publishing in a styl^e of great'
elfigance apdsplendewr. Perhaps a brief enurueration-of the in-»,
cidents which induced Mr. Humboldt to visit -tfeose superb and
iDnantic regions of the New World, may not . be viiacceptable '
ti> the.ovriosity of our readers. ,. ' *r * '
Mk Von Humboldt is a Prussian genUeman of good property, iK*ho
spent the early part of his life in the acquiremeet of liberal kriow-
kdge, and ig.well acquainted with general physics, ^nd xmsth at-**
toelied to chemistry and its kindred branches. He has siifce
tpent several years in travelliog„ apd apply iVg the resources of
his. for tune and his knowledge to tlje pursuits of a liberal curiosity.
Influenced by such motives, heconimenced hi^ travels in Europe
^ the age of 21 ; and in the space of six' years he visited Ger»
laatiy, Poland, Hungary, France, Switi^t-rland^ England^ Italy,
and Spain, and returned to Paris in 1798. When it was pro-
posed by the Directors of the National IMuseum to send Captain
Baudin on a voyage of discovery round the world, f^tessrs. Hum-'
boldt and Bonpland, an excellent naturalist of Rochfeile, were
invited to accompany him. But as this scheme wast never car^
JW^ iuto $zecuUott| Humboldt was disappointed in this plan, and
N^
Hnmhold^s Vhymal Vitto tf. the F^atoriat lUgi^. $tZ
rcsnmed a project which he had previously entertained ot visiting,
' as a philosopher, the cuantries of the East. With this view he
was desirous of joining the cefeblfated expedition which b&d sailed,
ifrom France to Egypt; whence he intended to proceed through
Arabia, and by the Persian Gulf and the Arabian Sea to th«
shores of the English settlements in India. But the navigatMn
of the Mediterranean Sea being ha:?ardous, and the situation of
the French army in li^gypt becoming very criticdl, he wailed for
two months at Marseilles for a Swedish frigate, which was to
convey the Consul Skioldebrand to Algiers* But as'his pa-
tience was exhausted before the arrival of this frigate he pro-
ceeded to Spain, hoping to meet with a safe and ready convey*
ance thence to the Burbary coast ; taking with him a good col-
lection of philosophical and astronomical instruments which ho
had purchased during his residence in Engla\id and France*
Humboldt, however, hajd not resided long at Madrid . before his
views were turned to a different quarter of the globe, and he was
permitted by the Spanish Court, upon the most liberal terms, to
▼isit Jier colonies in the New World. He therefore immediately
invited his friend Bonpland from Paris, and these eager travel*
lersy fired with emulation and thirsting after discoveries, lost no'
time in preparing to visit the awfully sublime scenes of the trans*
Atlantic hemisf)here. They embarked in a Spanish vessel at
Corunna, in June 1799 ; and after touching at the Canaries, and
viewing the crater of the Peak of Teyde, a prosperous voyage
conducted them to Cumana in South America, in the following
month of July ; and they returned to France after an absence of
near six years ; (he greater part of which time was spent in view*
ing many of the most sublime spectacles and grandest prospects
in nature, amidst anxiety, fatigue, and danger.
JSistadcal Note on the Means ^employed by Astronomers for observing
the Sun. By J. C. BurC4^jhardt» — Conuaissance des Tetnsfor
1811.
' The great brightness of the suu*s light, not permitting us to
look directly at ' it, has induced astronomers to adopt various
means. for obviatiug this inconvenience. In the observation of
altitudes^ of .azimuths, and of distances, the ancient astronomers
principally made use of the shadow projected by one sight placed
upon another, with the exception of the case when the clouds
rendered the' shadow too. feeble, for then the sun was directly
observed. . There is only Helvelius who seems to have preferred
the method, of ret^iying the image of the sun through a small
apertuire in the first siglit, and projected upon some concenUric
\S$S On the Means enftotfed for oUerVwg the Stml
circle traced upim the second. Archimedes measured the diame^
ter of the sun at the moment of his rising, in order that he might
be able to support the brightness j as Fabricius did afterwards^
There remains aUo some eclipses of the sun, which appear to
jrequire theobservaUou to be made without any intervening ob-
ject, and it is probable that the ancient astronomers did thi3 }
Kepler assures us of it, and his testimony seems to be decisive,
as he was cotemporary with the change which took place in the.
method of observing eclipses. Astronomers either covered the
eye with a plate in which there was a. very small aperture, or en-
feebled the intensity of the light by looking at the image reflected
from water. Jounis speaks of the latter method; Tycho of the
A much more accurate mode of observing eclipses, is that of
. receiving the image of the sun on a white paper in a dark room ;
this was invented long afterwards, though a passage of Aristotle
might have led to it; for according to Kepler it is to Eeinhold,
Gemma and Maestlin, that we are indebted for this invention.
The first eclipse observed in this manner seems to be that bj
Maestlin, in 1579* Twelve years afterwards, Tycho observed
the eclipse oif 1591, hy means of a small hole made in a piece
. of pasteboard.
The observations of the sun in 1611, shew the superior utility
of the instrument by which they were effected. It was on this
occasion that Father Scheiner constructed a telescope, having
both the object and eye g^ss of coloured glass, in order that he
might be able to look directly at the sun at all times, which he had
been able to do before theit period only when the light was sufficiently^
wakened by clouds ; Scheiner added, that coloured glasses might
be applied to a Qommon telescope, but that the former method
was preferable ; experience, however, has proved the con-
trary. The use of smoked glasses probably dates from the same
epoch. Though Scheiner seems to be the first astronomer who
employed coloured glasses; yet it has been asserted that the
Dutch navigators made use of them in observing the altitude
of the sun previous to the periods when Scheiner adopted them in
Lis astronomical observations.
In mure modern times, it has been proposed to cover tbir ob«
ject glass with cobwebs, or with mudin of sufficient fineness ta
>, permit part of the sun's rays to pass through it. In reflecting
. telescopes, the brightness of the sun's light may also be dimi-
nished by a designed imperfection in the polish of the mirrors ; a
method which has been attended with great snccess. M. de
' Zach has proposed the use of Muscovy glass, having its twp
surfaces perfectly parallel, that it may w>X altf r the imag^ of tk%
sun..
Tabk 0/ Tidcifor the year 1811. SB^
Observations* — It has sometimes occurred to us that it might
be worth while to make some experiments on the efiects of object
kpecalums, or lenses pi very small apertures, for viewing the son
without incoqveniences. According to theory, they ought to
sinswer every purpose, although we are aware that seme difficult*
ties might occur in applying them to practice.
Table of the Tides for the year 18 11. Bjf Mr. Bouvard.-— Comuu^
sance des Terns ^ ^r 1 8 1 K
This table is calculated according to the theory which Air. La^
place has given for the greatest total tides that take place a day
or two after the full and new Moons, relative to the distances of
the moon from the sun, from the earth, and from the equinox*
The unit of height is the msan height of the total tide for a day or
two after the syzygy, when the sun and the moon at the nio*
xnent of the syzygy, are in the equator, and at their mean dis-
tance from the earth. By toted tide is to be understood the excess
of the half sum of the two tides of the same day above the in-
termediate ebb, according to the usage of Laplace in the Sd vo^
lume of bis M6canique Celeste.
Days and houn
\
Heights of the
of the Syzygy.
Tides.
9 Jan.-
F.M.
4h
. 25m
.night, 0*80
M
N.M.
5
54
night, 1*09
8 Feb.
F.M.
11
36
niorni 0*84
as
N.M.
4
12
morn. 1*15
10 Mar.
F.M.
6
27
morn. 0*89
S4
N.M.
2
21
night, 1'13
8 Apr.
F.M.
11
12
nighty 0-92
23
NM.
0
26
morn. 1*03
6 July,
F.M.
7
35
morn. 0*99
20
N.M.
11
15
mom. 0*84
4 Aug.
F.M.
3
2
-night, 1'03
19
N.M.
2
21
morn. 0*84
2 Sept.
F.M.
10
44
night, 1-10
17
N.M.
7
6
night, 0-87
2 Oct.
F.M.
7
25
morn. 1*11
X7
N.M.
0
18
night, 0'88
8 May,
F.M.
0
48
night, 0-92
t!2
N.M,
^^ \
51
morn. 0*90
6 June,
F.M.
11 ^
16
night, 0-93
20
N.M.
10
Jl
night, 0-82
31
F.M.,
.5
23
night, 1-07
No. 26.— VOL. Ti.
Z%
i^ Mr. Walker on the Barometer for indiedia^ the WeatKer*
16 Nor.
N.M.
4h.
37ni/
morn.
0-88
SO
F.M.
5
18
mom.
0-95
15 Dec.
N.M.
7
20
night,
0*89
29
F.M.
7
20
night,
0-87
From this tahle it appears that the greatest tides for the year
to which it relates are those of the 24th of February, 25th of
March, 3d of September, and 5d of October. These tides, par-
UfSiiieiFly the former two, are safficient to cause inundatioBS, if
they be favoured by the wind and other circumstances. It i»
therefore of considerable importance that the inhabitants of the
maritime parts should be apprised of the circumstance before it
happens, in order to prevent the accidents and ill consequences
i&at might result from the phenomena if not guarded against.
Observations. "^This is doubtless a very ingenious theory on a
subject of considerable practical importance; but it is manifest
that it must be greatly affected by local and cotemporary cir>
icumstances. This was also confirmed by the two tides which
followed the full moons on the 14th of August, and 13th of Sep.
tember 1810, the heights of Aivhich the table for the last year stated
at 1*06 and 1*09 ; but coficurring circumstances caused the for-
iner to be the greater.
1* On the Afptitation rf the Barometer for indicating the Weather^,
and for measuring of Heights in the Atmosphere.
2. On the Barometer. By Richard Walker, Esq.'^PkH. Mag.
Nos. 150 and 151. \
1. Me. Walker states that there are three circumstances
which ought to be attended to previously to inspecting the baro-
meter for the purpose of predicting the state of the weather:
these are, 1st. The state of the atmosphere with respect to its
clearness or the reverse, ^ndly. The direction of the wind, and
tvhether it be steady or Variable; afid 3dly. The height and
density of the clouds. He then points out •several circumstances
which he regards as signs of fair weather, which we shall trans*
cribe.
" 1. The barometer rising may be considered as a general in-
dication that the weather, comparatively \yith the state of it at
the time of observation is becoming clearer.
2. The atmosphere apparently becoming clearer, and the ba^
rometer above Haix, and rising, show a disposition in the air for
fair-weather.
3. The atQiosphere becoming clear, and the barometer above
CliAKttSAlL£, and rising, indicate fair weather.
Mr. Walker on the Barometer for iadkaiing the Weather. 9^)
4. The atmosphere clear, and the barometer near Fair, and
fising, denote continued fair weather.
5. Oar prognostic _of the weather is to be guided relatively,
thus: If notwithstanding the sinking of the barometer, little or
no rain follow, and it afterwards rise, we may expect con tinue^
dry weather.
6. If, during a series of cloudy rainy weather, the barometer ,
rise gradually, though yet below Rain, especially if the wihi
change from the south or west, towards the north or east^ohit^,
clear and dry weather may be expected.
7- The weathei tor a short period, viz. from morning until
evening, may comn^only be foretold with a considerable degrefe
of certainty. li the barometer has risen during the night, and
is still rising,' the clou'is are high and apparently dispersing, and
the wind calm, especially if it be in or aboat the north or east
points, a dry day may be confidently expected :•— The same rule
applies for predicting from evening till morning, ' '
8. During the mcrease of the moon, there ieems to be a grea*
ter disposition or effort in the air for clear dry weather, than in
the tvane ; but this disposition does not usually commence tift
about three or four days after the new moon, and ceases abotft
three or four days after the full moon.
p. The bai ometer should be observed occasionally thrice in the
^ay, or oftner when the weather is changeable, in order to notice
whether the mercury is stationary, rising, or sinking; for froQ[i
this circumstance, together with the direction of the wind, and
the apparent state of the air at the time, is informatioa to be
collected, and a continuance of the same, or a sudden change of
the weather, to be foreseen.
10. Lastly, Observe always — the higher the mercury shaQ
stand in the scale in each instance, and the more regularly pro*
gressive its motion shall be, the stronger will be the indication :
likewise, the more the wind inclines towards the north dr east
points, the greater will be the disposition in the air for fair
weather.
The indications of raini/ 'weather will obviously be the direct
reverse of those rules which predict fair weather.
Frost is indicated in winter by the same rules that indicate fair
weather, the wind being in or about the north or east points, and
the thermometer sinking towards 32°.
A fall of snow seldom comes without a previous frost of some
duration, and is indicated by the sinking of the barometer, espe«
cially if the mercuiy be below Changeable, and the thermos
meter at or near the freezing point.
When the temperature of the air is at or above 35', snow an^
rain sometimes fall together ; at a warmer temperature than 35^
seldom snows, and it seldom rains at a colder temperature.
i^9^ Mr. Walker mtJ^Sarmeiir far indkaikg the ITeatier.
I'hunder is presaged by the same rules which indicate rai|^
accompanied by sultry heat ; the thermometer being up to 75*.
Storms, hurricanes, and high winds, are indicated by the b»»
rometer falling suddenly^ or sinking considerably below Much
Kaik*
The barometer is known to be rising or sinking by the mercuiy
having either a convex or a concave surface, or by the percepti«
Ue rise or descent of the mercury if at the time of observatioa
the barometer be gently rapped.
If at any time the weather should differ widely from the indi-
cations of the barometer, it may be presumed, as is sometime
known to happen, that a particular spot is affected by local cir-
cumstances.
After a long and continued series of wet weather, we may,
when the weather becomes fine> expect an uninterrupted continu-
iahce of dry weather.
If after a long series of wet weather the barometer rise above
Cha170£abl8, and the wind veer steady (steadily) to the north
or east points, a continued duration of fair weather may be ex-
pected.
Slow and progressive changes in the barometer, with a fixed
and steady state of the wind, indicate permanency with the
change.
The barometer standing at or above Pair, denotes gtntraUy
fair weather although the atmbspheris wear at the same time an
unfavourable aspect.
Lastly, the greater coincidence tliere is of the circumstances
enumerated in the rules above mentioned, the stronger may oiir
confidence be in the expectation of fair weather, and in the con-
tinuance of it when present, by the barometer whilst high,
remainihg stationary or yarying but little, 'and the state of the
atmosphere, and direction of the wind, disposed to be settled.
In this variable climate, there is no reliance, I think, to be
placed upon any rules, beyond these above mentioned, for indi-
cating the weather for any length of time together, or for any
distant period.^
• The remaining parts of this paper n late to the measurement
of heights by means of the barometer, and independent of loga-
rithms. These consist of rules, tables of correction, and illus-
trative examples ; fsr which our plan obliges us to refer to this
original.
2. Mr. W. considers this paper as an appendage to that of
which' we have giver! the substance above. He considers water
as existing in the atmosphere in a state of both chemical and
fnec/tamcal combination: in the former of these states it is so com-
pletely incorporated with the air as to constitute with it one ho-
mogeneous transparent fluid ; in the latter, the minute particklt
JM*. Walker m the Barometer for iaikoHng the ff^eather. I95.
of Jtlie water are merely suspended in the atmosphere, forming
that appearance which is styled cloudy or misty. A dense state
of the air being fittest for chemical combination, clear, dry wea-
ther generally answers to the higher degree of the mercury in the
barometer, while the reverse takes place in a rare state of th«
atmosphere.
** It occasionally happens, however, that the atmosphere is
cloudy, and even wet, whilst the barometer is as high as Fair ;
and clear and dry, while the barometer stands as low as Ra iir^
The reason of this, in the first instance, is, that the air, having
become replete or overloaded with water, is incapable (by an alte«
ration of temperature, viz. the air and its contents having become
colder) of retaining or suspending it in a state of chemical combim
nation; and in the latter case, which happens after rain, succeed,
ing a continued dry state of the atmosphere, which having swept
down tiie vapour with it in its descent; the air, though then in a
rare state, is yet sufficient to retain the proportion of water, now
much reduced in quantity, in a state of chemical combina*
tion."
The more immediate indications of the weather that is ap*
proaching, are the alterations which are taking place in the den.
sity of the atmosphere, known by the rising or sinking of the
barometer ; in the former case, the weather becomea compara«
tively clearer, in the latter instance, more cloudy. Some re-
marks are then added on the range of the barometer in this cli*
mate, ^nd the influence of different winds.
" The capacity of air for retaining water in a state of chemical
combination is increased by coming from a colder to a warmer
temperature ; and diminished, by coming from a warmer to a
colder temperature/' Mr. W. thinks the immediate causes of the
directing and changes of the winds in this climate, as involved in
too much obscurity to admit of any satisfactory explanation.
He also observes, that an attentive consideration of the above
mentioned causes, and the more immediate effect of the varying
influence of the sun, the vicissitudes of the weather xpay be fore*
seen with a greater degree of certainty than is generally sup*
posed.
Obseroations.'^V^e have already stated several circumstances
which we conceive it indispensably requisite to attend to in pre-
dicting the future state of the weather, (see page 315 of the pre*
sent volume ;) and, as the subject is of such constant utility,
and the barometer one of the chief instniments by which atmos-
pheric changes are ascertained, we have been induced to give Mr.
SValk^r's rules for this purpose, without abridgement. They ap-
pear to be the result of continued observation, and though they
may not contain any thing but what is familiar to him who is ac*
fO^ ' Mr. Walker, on tie Barometer.
iquainted with tbe nature of the barometer, and accustomed to
observe its variations, yet their practicability renders them wor-
thy the attention of the young meteorologist. We have already
given a small table and rules for determining the heights of moun-
tains without the use of logarithms, (see tletrospect, vol. iv.
page 12.) and both those and Mr. Walker's, referred to in this
article^ may be regarded as easy approximations to the truth.
t" ■'- J ' ■
3. On the Barometer. By Richard Walker, Esq^-^PhiL Mag*
No. I5t.
3. In this paper, Mr Walker offers a farther elucidation of the
effects of the ditl'erence of atmospheric temperature on the wea-
tfaar; and remarks that a warm temperature of the air will re-
tain a greater portion of water in a state of chemical combina-
tion than a cold temperature, the density being the same in both
cases This circumstance will account for the almost constant
dry state of the lower regions of the atmospherf during summer,
and tbe contrary in the winter season. In winter, however, the
air is sometimes sufficiently dense to retain the water in a state of
chemical combination, notwithstanding the diminution of tem-
perature; The same circumstance will also account for the diife.
rent states of dryness or moisture of the intermediate seasons of
spring and autumn, accordingly as they approach more or less to
the temperature of either of the former seasons, Mr. W. like^
wise observes, that all he has had occasion to mention relative to
the effects of the different degieesof the temperature and density
of the atmosphere is exempliiied by the two following experi-
ments.
** In the first instance, by means of pumping out of a glass
receiver (containing air apparently dry and perfectly transparent)
a certain portion of the air it contains, when the air being rare-
fied, deposits a certain portion of water it originally contained in
chemical combination in a cloudy vapour ; which, upon re-admission
of the air, is re.absorbcd ; and in the second instance, by ab-
stracting heat from a glass vessel containing atmospherical air,
and again restoring the heat. The latt'^r circumstance is likewise
instanced, naturallyy by what commonly happens in the course of
a hot summer's day, particularly when the ground has become
very moist by previous rain ; the vapour ascending visibly in tbe
morning, disappearing during the middle of the day, and descend*
f;j^ visibly again in the. evening."
The variations of atmospheric temperature which ace not
cau?ed by the direct influence of the sun, proceed from the con-
Version oi water into vapour, which produces cold;, and th?
\
On Carnages J ^oadsf and t)rmght of Horses* jJJS
condensation of vapour into water, which occasions beftt : for
^his reason, the barometer generally rises in proportion as th%
thermometer sinks, and vice versd. Thunder often succeeds &
continuance of hot dry weather, which is favorable to the coU
lection of electricity. An extraordinary elevation of the baro*
meter is ascribed to the meeting of two opposite currents of ait
over some particular spot; and an unusual depression ft-om twd
currents proceeding from that place. Mr. W. thinks the mooil
has not the least mechanical effect upon the weather;* and he
was led to the remark in one of the preceding papers, on the
difference in the weather during the increase and the wane of the
moon, by observing that the eclipses of the sun were much less
pbscured by a tloudy atmosphere than those of the moon ; aqd
this has been somewhat confirmed by subsequent observations.
Observations on Wheel Carriapres, Roads y and Draught of Hones;
Investigations of the mechanicdl Modes of Actiofi of the Horse^
and of the Size and Breadth 6f Wheelsy and Descriptions of three
new Species of Wheels ^ contrived to facilitate Draughty and to
preserve the Roads '; with some Remarks^on Axles and BoxeSy and
an Account of a proposed Improvement in Harness, By JohH
Whitley Boswell. — Reports of the House of Commons, and
" Repertory of ArtSyNo. 97, 98, S9y Sec. Ser.
' Mr. Boswell has divided this essay, which is of considerable
extent, into three parts, and each into portions dedicated to par<»
ticular subjects. NVe shall endeavour to follow him through
them in their order with as much brevity as possible.
Part /. Vassing by the introductory letter to Sir John Sin-
clair, Bart, ^and some pages of prefatory remarks, the first
topic that presents itself is that of - ^
Carriages. Mr. Boswell commences this part of his inquiry
Vith this just and obvious principle, *' that the mode of convey-
ing goods on a road which is the most advantageous to the pub-
lie is that by which a horse can transport the greatest load with
the most ease to himself, and the least injury to the road." Ex-
perience has fully proved that both these i|nportant conditions
are best answered by the use of single horse <;^arts ; and by a ge-
neral adoption of them it is conceived that a tenth part of the
expence of repairing roads might be saved. It is also recom«
meDded that these carts rest upon springs, according to the plan
of Mr. Lovel Edgeworth, and horizontal springs are deemed the
best for this purpose, and may easily be made sutFiciently strong
to ^lippOrt any load that a single horse can draw. There is one
advantage attending the use of springs for cart^ whicji appears
3g6 Mr. Soiwdl OH Gmri^geif Roaitf (md Draugki of Banei.
to have escaped the notice of those who have written upon the ,
subject; *' this is, that they save the road from injury at eveiy
jolt they prevent; they also hiader the displacement of the
materials of the road : and this circumstance alone would ena*
ble a road to last . longer without repair where spring carriages
alone were used, than one where those without springs were em-
ployed, even though of the best construction in every other
respect.''
Roads. Mr, 6*. thinks that no roads can come in competi*
tion with iron railways, and suggests the following plan for their
construction. Most of the great roads in the kingdom are of
sufficient width to allow of a railway along each side without any
inconvenience ; and these would not occupv a greater breadth
than is usually appropriated to footpaths; for which purpose
they might also serve.
lliese railways could only be used for the conveyance of goods,
as carriages for passengers could not pass un them at their usual
swift rate, at the same time with those of the former descrip.
tion. ** The best mode of forming iron railways, is that in which
the rail rises up a few inches above the level of the ground, and
is received into a groove in the wheels, which move on them ;
as on such rails no gravel can lie to interrupt the motion of the
wheels ; and if with such rails, the wheels were formed Hat at
each side of the groove, so that they could occasionally run on
common ground, the whole perhaps would be as convenient as
could be wished.'* Some remarks are likewise offered on stone
railways, and it is proposed to join the stones by small separate
blocks, let into their substance at the bottom, or by oak tree-
nels let into the centre of each. A good method of forming the
foundation or bed for the stone rails to rest upon, which is an ob-
ject of importance ; would be to pave it with common paving
stones. Next in order to these railways in both durability and
economy, is a paved road, about 15 feet wide, for heavy car.
riages, accompanied bv a gravelled road for those of lighter bur-
den. When the breadth of the highway exceeds 30 feet, it would
be very beneficial to divide it into two separate ways ; as in this
case it would require little more than one fourth of the materials
to form them at first ; they would be much drier, and consequent*
]y more durable ; and they would afford a greater convenience for
carriages, and be more equally worn. Mr. B. also urges the neces-
sity of submitting the management of roads to experienced engi-
neers, instead of the ignorant interested persons who in general
have the direction of them, and insists that the grand object to
be attained in their construction is the preservation of the same
level as much as possible. For every five degrees of elevation o£
the road below 40*, an additional horse will be required to draw
the same load. 'The difficulty of drawing a load up bill has go^
JSr. BtameU m^Carmgn^ Rotds^ mid Drmtghi tf Horm. ZSff
•eimlly been undervalued, from estimating the effects of hills ofily
«e inclined plitnes, without taking into the account the loss of power
the horse sustains from the ascent ; for it is evident that the real
difficulty will be in the compound ratio of the loss of power in
^the horse, and the increased rasistance of the load. . This same
attention should be paid to the construction of roads in this ri^pect
as to that of canals. It is also suggested, that a long rope or end*
less cbaie, drawu by any adequate power at the top of a hill,
where any considerable ascent unavoidably occurs, might be used
with advantage for assisting the horses in passing from the bottom
io iht top. It is likewise asserted, that the insular nature pf
this country renders it demonstrable, that roads may be aiadeall
jround it on the same level, within view of the sea coast.'' From
ihese principles *^ it follows, that the proposed road from London
io Edinburgh, menliooed in the Reports, might be found on a
•ingle level for the whole distance.'' This ^ould, however, ren*
der the road very circuitous in some places, but this is not deem*
«d a sufficient objection, as it would re<]uire double tbe number
of horses Io draw the same load up a hiil which rises only about
three inches in a yard, as to c<vnvey it' on a level ground^
Paet IL Mechanical Moda rf Action of the Hor$e. Besides
gpuscttlar strength, the horse, frpm'the structure of hia frame and
liis weight, possesses powers of a mechanical nature. The force
«f a horse arising from his weight, when he rests. on his hiod^
legs and raises his fore feet from the ground, Mr. B. states to be
•qual to a weight equal to that of the horse attached to the part of a
straight lever (extending obliquely upwards from his hind foot to
iiae point of liraught) which is situated perpendicularly under his
ie«atre of gravity. This he illustrates by means oi, a figure, and
draws from it the following conclusions. 1. ^' The higher a wheel
.as the less will \it the power which the horses applied in the above
tnanner, can have to move it forward. 2. The horse will have
more power ov<e4' a load on the ground than over one placed on
aay wheel. 3. The farther forward the centre of gravity of the
horse is placed, the greater will be his power applied in this man-
oer. 4. The power of the horse io this position is diminished by hav-
ing the^ointof draught before the centre of gravity, in a certain
furoportion. 5. A weight placed on the horse's back increases his
power applied in this way ; but it should not exceed 2 cwt. 6. The
load drawn oa high wheels, by the horse using this mechanical ac-
tion, will be moved forward at an unequal pace. And, 7*
Wheels intended to be acted upon by the described motion of the
liorse, should sever be so higk that a line drawu from their axles
to the point of draught, should form an angle of ten degrees, with
4he faoriaontal line drawn through this point.
The second noechanical mode of action, and which is inore iier
jhlo. 8&---V0JL. vu 3 V
vV
398 Mr. Sosveli on Carriages, Roadt^ and .Draught tf Sorsei,
quently resorted to than the former, is that in which the horsi
rests on bis fore and hind feet at the same time, and leans foi^
ward. This action is also elucidated hy a lignre , and the follow^
ing inferences drawn. 1. All the conclusions relative to the
height of wheels that were drawn from the first mode of action
will apply to the second, for the same reasons. 2. The best po-
sition of the centre of gravity of the horse differs in this case from
that in the former, being more backward. 3. An additional
weight on the back of the horse increases his power in this mode
as well as in the first.
In a third mode of action the horse rests the fore part of his
body on his fore legs, so that in moving forwaid, the point of
draught maintains a horizontal motion, and the weight of the
horse acts as a propelling power. In this case his weight assists
him less than in the others. The most favourable position for the
centre of gravity will be farther back than before. Weight may
be applied on the back with advantage. When the motion is
used the crupper only will descend and ascend ; it will be applied
in the slightest draughts, and fatigues the horse least. Low
wheels are favourable, as they cause the line of impulse to coin,
cide more nearly with the line of draught. The horse can apply
this kind .of action only when he walks r When he trots, his
force is exerted, and the load impelled forward by a succession of
impulses^ in each of which his weight acts with an accelerated
velocity.
Mr. B. observes that the height of the wheels should, in no
case, exceed that of the point of draught, but be rather below
it ; otherwise a pait of the force woqld be spent in drawing the
lo&d directly downwards. He also accounts for the circumstance,
that carriages in rapid motion have their pressure on the earth di-
minished. This he conceives arises from the oblique position of
the line of draught causing a part of the velocity, (we suppose
Mr. B. means the momentum acquired by reason of the velocity)
to be expended in raising the carriage from the ground ; and the
rebounding motion it receives from the obstacles with which it
meets in its progress.. The combined action of these two causes
makes the carriage move forward by a succession of small leap's^
ibstead of a regular rolling motion, as is easily perceptible in
those moving quickly over a rough pavement.
On Carriage fVhtels. From Mr. Boswell's inquiries on this
subject, after shewing that in going over obstacles, passing ruts,
and for sandy and muddy roads, high wheels are preferable, he
draws the following conclusions. l.That there is an advantage in
Laving the point of draught far forward in ascending a hill* 2. It
is also advantageous to have the point of draught as low as pos*
sible. 3. The horse will have more power the farther forward be
can advance his centre of gravity ; and hence appears the neces-
Mr^ BorweS on Cmrwge$f fioadsy and Draug/^ o/Honei^ 399:.
«)ty of. leaving the horse's head perfectly free from any curb*
4. Weigl^i laid un the horse's back will assist him in drawing up
a hill ; and consequently one horse carts possess a great advan-
tage in hilly couutries, as part of the load can be made to press
on tl^e back of the horse.
On the Bnadth of W/ieels. This part of Mr. B's essay is oc-
cupied in shewing, that though broad wheels resist pressure bet-
ter than narrow ones^ there is a disadvantage attending them,
arising from the greater resistance they meet with from the mud,
&c. when traversing soft roads. Hence he contends .that nume-
rous wheels of narrow breadth are preferable to few of great,
breadth, the sums of their surfaces in both cases being the same.
A contrivance for bniting the advantages of both large and small
wheels, Mr* B. thinks is still a desirable object, aud this he pro^.
poses to give in the next part.
Part HI. " On new invented Wheels to facilitate Draughty and
preserve Roadsj aud on an Improrv€7nent in Harness** '^^DoubU Wheel.
These consist of pairs of wheels united by the same axle, which
turns with them. In each pair the wheels are to be placed with
their naves eight or ten inches distant from each other, and that
part of the axle which is between them is to be made round- and
smooth. On these the cart is to be supported by oblique pieces
which pass upwards to the shafts, and are connected with them
by upright supports. Between these oblique pieces and the axle,
beds of metal are to be fixed by means of divided socket in the
usual manner. The wheels may be each 3| feet high, though
they lie beneath the cart : and each three inches broad on the
sole. As each pair will only h^ve to sustain the weight of ^
single wheel, they may be made much lighter than those of the^
.usual construction. The advantages which would result fron^
this mode of constructing wheels are stated to be the following.
1. That with an equal bearing on the road they would only ez^
perience half the resistance of wheels that are double their breadth.
2. The vertical play of the axle would cause each separate wheel
always to bear flat on the road at the same time« 3. They would
pass obstacles and ruts with half the difficulty of broad wheels.
4. These wheels could not be fixed so as to run conically ; and it
would be extremely difficult to evade regulation respecting them.
And 5. Both the wheels and the axles would be more durable than
those that are now used singly. These wheels may be adapted to
waggons as well as carts, and more than one upright support may
bemused when necessary. 1 he oblique piece may also be supplied
by a spring which would be an improvement, both in facilitating
the draught, and in doing less injury to the road.
Combined Wheel. This second method of arranging whcelt
proposed by Mr. Bos well, is designed to unite the advantages of
^oth ^mali and large wheels ; and is to be accomplished by caut«
ifig the smalft \trfae^1 to run up6n the inside of tlie fellies of ih^
Ikfge one, ftom trliich a rim projects to support it. Tbe edge
of tbe small wheel i« hollowed to receive the rim ot the large one**
within it, like the wheels tised on convex railways. The' load i$
caused to rest entirely on the axle of tbe small wheels, and the
Ifirge ones only serve to keep them in their places. The small
wheels may be itiade entirely of cast iron, and tbe inside of tire
rim which supports them, must be covered with iroB to sustain
the wear that must take place in that part.
Tbe advantages are stated to be, that in passing obstacles, thr
combined wheel will have more power than the single larg^ wheel,
and the load will lose less of its momentum. In passing ruts,
and traversing sandy roads. See. they will also be superior, A
carriage with wheels of this kind, may be managed so as not 16
be easily overturned, and will afford the horse more power than
one with common wheels. 1 he author considers the combined
wheel as superior to the double wheel in every respect, except in
its requiring more accuracy of workmanship.
Spring fFheel, The two kind^ of wheels above described, are
designed far slow draught, but this is calculated for swift motion.
Each of the spokes is constituted of a single elastic plate o^
steel, bent into tbe segment of a circle, and made of the usuat
temperature for cbach springs. These springs are t6 be (sxe& to
the nave alternately, in separate rings, forming tbe combination
caMed double dishing. The spring wheel would possess the ^to*
perty of prevt^nting all loss of momentum from common obstacles
and ruts ; would do less injury to the road ; and would also last
much longer. The chief objection against it, woulA be the ori-
ginal expense, Mr. B. likewise presents some observations in
this place relative to axles and boxes ; the latter of which he re-
commends being either made polygonal within, or lined with
ffome elastic substance.
On Harness* . Mr, B. considers the harness of a horse of great
Jitiportance, for if it press on any tender part, it will both injure
the hx)rse, and cause him to exert his strength with reluctance.
In this proposal it is designed to throw the pressure of the draught
njron the front of the horse's breast, and on his back. A breast
pad made exactly lo fit the front of the breast, is to be sustained
by a strap passing over his neck, and to be secured bel6w by
another strap strong enough to bear the draught, and passing
under a surcingle whichjgoes over one of the small saddles now
generally used in harness. In drawing a cart or .gig, the strap or
trace passing between tbe fore legs of the horse, is fastened be-
neath his belly to an iron bow connectod with tbe shafts ; bixt if
two horses are to draw abreast, the traces are to be fastened td a
Cross bar passing under their bellies, and beneath the pole of the
carriage. A strap, is also to be fixed behiod the horse, against
wltidi he might exert bis strength, for the purpose of backing
when nece^ary. The advantages attending this mode of bamet^
ging horses, are said to be, *' lat, Thut it presses on no part that
can endanger the Hfe of tlie horse, or do him any injury. 3d,
That it leaves his shouMers perfectly free for aetion, yrhieh are
more or less impeded by all the common kitids of harness. Srd,'
That it gives him greater po^ver by ' the low position of tb«
point of draught wh^h it causes.**
Oi9erotttums»^*^Th9Lt branch of mechanical science which re-
rates to the construction of' wheels and wheel.carriages, has, at
difibrent times, given rise to a considerable degree of controversy^
and like knany ot^er ph^'sical subjects, appears to have often been
both misunderstood and misapplied. Some of these erude opi«
nions may easily be traced to the fertile sources of ignorance and
prejudice; some have been the mere speculations of theorists^
4nd many others have originated either from their authors not
having taken into consideration all the circumstances connected
with this complex subject, or from not having allowed eaeh its
due weight in the scale of cakutation* In sbbrt, it is the want
of a proj)er combination of theory and practice, pf scientific in-
vestigation and experimental results, that has rendered the great*
est part of all that has yet been done on the subject of so little
value, and makes a dissertation of this nature, considered on
these principles, still such a desirable object with the publitiL.
Any thing like this, however, wonld be foreign to our purpose^
as we must content ourselves with a few brief remarks.
That we do not consider the present essay as the dissertatioA
which we have designated, » sufficiently evident frona what i^t
have already said. It is by no means destitute of many usefuh
remarks, mingled with obscurity, inaccuracy, and hypothesis.
What Mr. Bosviell has urged relative to single- horse carts, is cer-
tainly deserving of attention ; but it does not appear to be so
new as he seems to think, as the Yarmooth carts have for a long
series of years been used upon this principle ; and those who^
have visited the North of England, must have witnessed the very
great loads that are dra^vn by a single horse in the same manner.
The horses in general are much inferior in both size and strengt])
to those used for the draught in the neighbourhood of London,
and each will draw from 15 to 20cwt. which is much more than
usually falls to the share of each horse by which loaded waggons
are drawn. Mr. B. think a that about one- tenth of the weight
may be laid on the back of the horse with advantage to his drawr
ittg the remainder ; which is a refnark deserving the utmost atten*
tioo. He appears to attribute this advantage chie6y to the increase
ed weight of the horse, when exerted, according to the first mode
of mechanical action which he has described ; but does not daily
4M Mf. Baitoeil^cnCamagMf Roatk, and Drmtght efS^iui^^
expremnce provt, thattke greatest part af this advantage arista
from tbe feet of the. horse being more fmply fixed to .the ^ojuiid
by the additional pressure, which enables him to exert his muscu^
lar strength with greater efiiect? This mode of action, 4t. leasts
in point of duration, exceeds ihe.other in a very great r^tia ; and
consequently, any momentary efiect of the one, will be mt)re than
counterbalanced by the constancy of the other.
In fact, Mn Boswell has very much misunderstood the, nature
of the action of the horse, when. he. has attempted to illustrate it
by a comparison with the principle of the lever : Jirsty when, he
makes the hind feet the fixed point, he /orgets that the great ex^
ertioij of the horse is employed in keeping the hind legs extended,
and that this exertion must be increased^ iu> proportion as the
force of draught is increased, by loweriug the pi>int.tpi .which it i&
applied ; if all the horde's joints were stifieui^d in the ej^t^p^ed po«
sition, his reasoning would for a moment be correct ; b.ut it would
lie but for a momei^t,; and the same objection would be still ap<*
plicable to it, whic^ invalidates his arguments ; in the^ecpf?fl[ ca3e#
where he considers all the horse^s l^s as straight levers, m this
ease it is very true, that the fwop of the draught ^would be in*
creased by lowering its line, but it must be fememj^ered that the
sipace through which the weight would be drawn, would be dimi^
nished exactly in the same proportion ; aud .after the hofse had
proceeded to fall a little way, he would have to hobble up again
96 well as he could, to retract his upper parts, in order to be able
fo carry forward his foot through ano.ther.imperf^ct step.
With respect to the most advantageous direction of drs^aght in
general, there is a practical rule which ^has been Jaid down by
Dr. Young, from mathematical (Principles, and which ma^, per*
haps, deserve to Le more generall}' known to mechanics ; it is
this, that the inclination ought to be precisely that of ,a road, op
yrhich the carriage would just begin to descend ^y means of its
awn weight, supposing the materials of the rqad the same with
those of the road on which the carriage is intended to travel.
But it must be recollected that the form of the horse^s shoulder,
and tbe advantage of adding somewhat to his weight, may often
make it advisable to increase, rather than to diminish this in«
clination.
We are at a loss to understand on what principle Mr. Boswell
expects that two narrow wheels should exhibit less resistance
than a single one of twice the breadth : but we shall willingly
await the result of experience with respect to the merits of his
singular inventions. We can, however, scarcely think it possible,
that harness made after his plan, could fail to gall very materially
the chest of the horse.
Mr. B's. observations on roads and railways, are, upon the
whole, botb judicious and practicable ; for besides the great addi^
Mr. Bostoellon Carriages^ Roads, and Draught of Horses. 409
tiotial e)cpetice of constructing broftd curved noads, tfa^ir sides wear
daily into a more inconvenient, and sometimes dangerous slope.
A railway of the same kind Mr. B. recommends, is now construct*
ing on the foot-path by the side of the road from Cheltenham to
Gloucester. Mr. B. hdwever, lays a great deal too much stress
■poh the vibration which their stone foundations would receive^
from the passage of heavy carriages ; and the circumstance of
tbe houses in London being sensibly shaken by the same cause,
t^hich he has cited as a corroborating instance, is not at all to the
point, as this arises from the roughness of the pavement, which
^roald be completely avoided in railways.
This authoi-'s spring wheel, we likewise think well calculated
for all carriages, where light loads, and quick re-action is the ob*
ject ; and the use of springs in general, certainly deserves com*
niendation. We, however, hesitate not to say, that he who can
assert that *^ it is demonstrable that roads may be made all round
the island (Great Britain) on the same level within view of the
tea coast," cannot have any very intimate acquaintance with the
nature of bis subject, or at least'has ventured an assertion which
is much too strong. What would Mr. B. make of the Land's,
end, or of the Ord of Caithness f Id the perusal of this essay, we
also meet with expressions like the following : ^' for if you place
him (speaking of the horse), on an ascent so steep, that a line let
fall from his centre of gravity, must be vertical." And again,
^ by which the centre of gravity of the horse would act on the
different hills.'' But as we had much rather dwell upon what is
useful than what is absurd, and merely point out these faults as
warnings against future errors of the same kind, we shall not en*
large on this head.
Description of a Camp Telegraph, invented by Knight Sfekcca,
Esq.-- Phil. Mag, No. 151.
Mr. Spencer remarks that important advantages result from
the. use of the telegraph in both naval and military affairs, and
he conceives the attempts which have been n^ude to introduce it
' into our land service generally havt; failed from the want of some
practicable system : he thinks also that if a telegraph could be
constructed which would be as certain in its /Operations as
the present fixed telegTaph, and al the same time so simple
and portable as lo require no separate establishment, either for
its transport or management, it would be a most important ac-
quisition in the field." Mr. S. has endeavoured to obviate these
difficulties, and the result he now offers to the public under the
name of a camp telegraph, with which he has frequently asked a
404 Mr. Spencm'*9 Camp TeJsgrapk
qucstioa at tbe distance of «i> wtileSf aud received an answer in tha
space of three minute$» He also states that an officer^ after two
hours' applicajtion, would be able to direct every station* wbik
the duty of signal man might be peiformed after lialf an hour's
drill.
In working with this telegrspb, which is numerical, «ach di.
rector is to be assisted by three Bigual men ; one of whom must
be furnished with a staff, 13 or i4 feet long, bearing two flexible
balisi about three feet in diameter; ^is staff is technically called
tbetentre-paint; each of the other signal men have also a staff of
10 feet in length, mounted with one ball of a similar kind. Tha
signals are to be made at the command of the person who has
. the direction of the station, and who takes his stand behind the
centre point* These are performed by each signal-naan march*
ing a certain number of paces to the right or left of this point,
and instantly elevating bis staff and ball which has been con^
veyed to his destined place at trail. The signals are to i)t re*
peated at the corresponding station, when the director gives the
word " dumn" £^<1 the signal-men retire in double quick time, to
the rear of the centre-point, with their balls lowered in the same
manner as when they advanced to their stations.
Mr. S» gives tins following directions lor constfuctini^ this
telegraph. '* Take an ash or deal staff of the required length,
and the substance of a stout pike. Take twelve whalebones,
four leet six inches long, and itx, them at nine inches from the
top of the staff, in the way the whalebones of umbrellas are
fixed ; fix the lower end of these whalebones to a strong slide, .
(like the slide of an umbrella,) the. pipe of which must be X%
inches long, and project upwards. To the M>p of this pipe
stretchers 18 inches long must be affixed, aiid also to the middle
of each whaleboue, like the stretchers of an umbrella* to keep tho*
ball stiff when in use. There must then be a strong umbrella
spring tixed on the staff, at three feet from the upper fastenings
of the whalebones, or top of the ball, so that when the slide is
pushed up, the whalebones will form into a sphere of three. feet
diameter. The skeleton of the base being thus prepared, it is to be
covered with glazed linen, half black and half white, divided
tertically, •
The signal of communication is made by placing a signal-marr'
at 20 paces distant on the right and left of the centre point. The
period is expressed in the same manner; but the distances are
only three paces. The signal of error^ which is to be made
when the preceding signal has been mistaken by the correspond
dent, is performed by placing one signaUman three paces to the
left, and the othe*- 10 paces to the right of the centre. 1 he re*
peatittg signal is to be, made when the last communication is not
Mr* Spencer's Camp Telegraph. 405
undtrstood. This is done by placing ooe signal-man three, and
the other 20 paces to the left. The following is the method of
expressing the numerals.
No. 1* Is made by placing one signal-man three paces to tht
rtg^^^ of the centre point,
2. By placing one signal-man tO paces to the right:
3. By placing one signal-man 10 paces, and one 28 paces
to the right.
4« By placing one signal-man at three, and one at five patet
i ) the right.
5. By placing one signal-man at 18, and one at 20 pacei'
to the right.
6; 7j 8, 9, and 0 are made exactly in the same manner, only
substituting left for right.
When the signals are to be made in the night, lamps must be
substituted for the balls, and these are to be suspended in frames
in such a way that they may always be in a vertical position. It
is recommended that each lamp have two hollow lenses, about
four inches diameter, filled with coloured transparent fluids, by
which they will readily be distinguished from common light.
When the stations fixed upon are below the horizon, the white
sides of the balls are to be turned towards the correspondent, and
the men dressed in white; but if the stations be above the hori-
spn, the blark sides are to be presented, and the signal-men to
be in uniform.
Observations. — Mr. Spencer is already known to our readers as
the inventor of the Anthropo-Telegraph, described at page 42, of
our present volume, and the object of this as well as of the former
contrivance, was to produce a portable military telegraph, which
should be applicable at all times and in ail places. He has cer-
tainly succeeded very well in attaining simplicity and portability ;
but the signals will require a much longer time for their execu*
tion than those in his former invention, while they may be seen
, at a greater distance ; since the diameter of the globes is double
that of the disks.
■BS^SBSBBB
Recent State of the Iron ManufaCtorg in Great BrUain.'-^Panttilo*
gia. Article Iron.
Iv the year 1S06, when the minister proposed to levy a tax
upon the manufacture of iron, the owners of the 133 iron-works
which then existed in Great Britain, depu^d 14 of their number
to assemble in London, and arrange the information which was
submitted to the committee of the House of Commons, on the
bill for imposing the tax, with a view of shewing its impolicy and
No. 26. — veL VI. 3 «
406 Receni Side of the Iron Manufactory in &reat Britdmm
ruinous tendency on a manufacture bo essential to the success of
almost all branches of British industry. It is through the kind-
aess of one of these deputies that the following abstract of the
iron furnaces which were woiking with ooke or pit coal in Great
Britain, in the spring of IA06, has been made .public.
Cumberland has four works, containing four furnaces, all in
blast; which make 1491 tons of pig iron annually. '
Derbyshire has eleven works^ containing eighteen furnaces, of
which only twelve are in blast, making 10,631 tons per annum.
Gloucestershire has two works, containing three furnaces, of
which only 2 are in blast, making 1629 tons per annum.
Lancashire has three works, containing four furuaces, of whiab
only two are in blast, making 2,500 tons per annum.
Leicestershire has only one work, with a single furnace, which
is now out of blast.
Monmouthshire has three 'works, containing three furnaces,
all in blast, making 2,444 tons per annum.
Shropshire hfts nineteen works, containing forty-two furnaces^
of which only twenty-eight are in blast, making i4,S)96 tons per
annum.
Staffordshire has tweuty-iive works, containing also forty- two
furnaces, of which only thirty-one are in blast, making 49,460
tons per annum.
Yorkshire has fourteen worses, containing twenty-seven furnaces,
of which only twenty. three are in blast, making 26,671 tons per
annum.
South Wales has twcnty-iive works, containing forty- seven
furnaces, of which thirty-six are4n blast, making 75)601 tons
per annum.
North Wales has three works, containing four furnaces, of
which only three are in blast; making 2,075 tuns per annum.
Scotland has twelve works, containing twenty.seven furnaces,
of which eighteen are in blast, n^aking 23,240 tons per annum.
So that Great Britain contains in the whole 122 works, con-
taining 222 coke furnaces, of which l62 are in blast, and^ make
250,406 tons per annual, being on an average 1546 tons in each
fuFoace.
There still remain eleven works in different counties, contain,
ing eleven furnaces, that still use charcoal^ all of which are ,in
blast, and nmke 7,800 tons per annum, or on na average 7^9
tons in each furnace.
From this abstract, it appears that the 133 furnaces at the
period above specified produce 258,206 tons of crude iron an-
nually, though only twelve years before the annual produce had
been estimated at 100,000 tons. The number of furnaces out of
blast or not working at the time amounted to nearly one-fourth
^ of the whole, and this circumstance is attributed in great part' to
Recent State of the Ir&n MmMfactwy- in Gr&ti Britam. 407
Ui6 frequent repairs which the lining and hearth of a blast £ar<.
nace require ; and some had been blown out, . or ceased to work
i^ consequence of a temporary failure of their supply of either
'iron, stone, or coals, within the owner's, or lessee's lands* The
average produce of each of the l62 coke furna(;es in blast, 1,54$
tons of pig iron. At Cyfairthfa, in South Wales, the average
per furnace is as high as ^,6 1 5 tons per annum ; while in 13
others the average quantity falls below 500 tons; at Dewey, in
North Wales, it is stated at 150 tOiis only.
** The average quantity made at each of the 122 coke iron*
works^ is 2,070 tons per annum ; seventeen of these works make
4,000 tons each or upwa^'ds ; the seven largest are Cyfarthfa, in
South Wales, 10,460 ; Old Park, in Salop, 8,359 ; Blacknoour,
in South Wales, 7,S46; Pennydarran, in ditto, 7,803; Ketleyi
in Salop^ 7,510; andCarron, in Scotland, 7)3SO tons per annum;
while at the same time eleven of these wurks fall short of 500
tons in the quantity which they make. The three least of these
are stated to be Golden Hill, in Staffordshire, 184 tons; Dutton^
in Cumberland, 175; aud Dewey, in Norih Wales, 150 tons'of
pig iron per annum.
Ninety-five thousand tons of this pig iron, manufactured in
Great Britain, are afterwards rendered malleable. The capital
employed in the manufacture of the raw materials only^- is esti*
mated at five millions ; and it furnishes employment to 200,000
perso;is, independent of all the labour necessary to fabricate ^•
ticles.of iron."
Obierpations, '^from the preceding sumipary it is evident, tl^a^
the number of charcoal furnaces in this country has now become
compar:itively small, owing to the decrease of wood, and the
o^n&equent want of fuel for working them ; though till about 40
years ago they were general in England, as they now are on the
Continent. In the reign of King James the First, this manufac*
ture was in a very flourishing state in Great Britain ; but from
nearly that period the progress of cultivation becan>e more r&pid,
which effected a diminution of fire wood, and a decline of the
iron manufacture, as the necessary consequence. This decline
was so great, that the ^advantages resulting from this branch of
human industry were nearly lost until the process of making iron
with pit coal was established, which has placed -it upon such A
permanent basis, that it is now capable of being extended to any
magnitude without injuring the agricultural interests of the coun-
try ; as the iron^ though it produces so much, costs nothing that
is otherwise useful, but the labour .of its reduction.
In order to convey in a few words to such of our readers as are
not acquainted with t^is subject, a general idea of the manner
i^ which it is now conducted in this country, it may be observedi
408 Recent State of the Iron Mattiffactory in Great J^tiiak.
tbat a blast furnace of the common size is charged 48 tinies, with
eight bushels of coke each time, in the course of f 4 hours. To
iproduce this quantity of cokes, requires nt ar 7^4 bushels of coals
per day. The furnace also consumes about nine tons of dre
and limestone in the same time. The produce of metal obtain^
from this consumption is about ^0 tons per week in summer,
and 30 tons in winter, when making the best iron, or what the
liianufacturers call No. 1. Of No. 2, the quantity is from 35'
to 45 tons per week.
At many iron works, three of these furnaces and their foun-
dries are constantly in use ; the coal and iron mines, with forges
and rolling mills for making iron into bars, belonging to the same'
concern; the great number of steam engines,/ mills, waggons,
horses, workmen's tools, frequently a railway or canal from one
part of the works to another, a large farm to maintain the horses,
and the capital necessary to prosecute such an undertaking, will
give some idea of the opulence and general knowledge necessary'
to enable an iron master to conduct his business with advantage
to the community, and profit to himself.
Engraved States for teaching Writing and Arithmetic, By Mr.
Thomas Warhev, — Trans. Society ef ArtSy Vol* 27.
On one of tie smaller slates which Mr. Warren sent to the
society as a specimen of his invention, faint horizontal and pa-
rallel lines are drawn across, and the nine numerals engraved in
the alternative lines drawn on one side, and the small letters of
the alphabet drawn on the other. The scholar is to copy in these
lijnes with a slate pencil, the letter or figure placed at the begin-
ning ; and when the lesson is finished, the work is to be rubbed
but, and a fresh one commenced. Slates of the same size are also
proposed in a similar hianner with capital letters ; and others of
ri larger kind, with examples in the first four rules in arithmetic.
" In making use of these slates, the slate pencil is recommended
to be placed in a quill, and to be iield exactly after the manner of
a pen, by which means the hand is made pliant, preparatory to
the use of that instrument on paper." The expense of small slates,
without capitals, is 15s. a dozen; and of those with capitals, a
guinea per dozen.*
Ohsercatio'ns. — Various expedients hav.e lately been devised for
facilitating the diffusion uf useful knowledge, and different modes
of bringing its elements more immediately within the reach of
ihh lower classes of^ society, and consequently, for conferring its
advantages" on them in a greater degree, have recently been
Jidopted with success. It is almost needless for us to say that we
CumberiantM Stkimtfor-pres&vmg SUptortcked Persons, 400
regard the invention dtseiibcd in this articli^, as one of those
which merits a^trial, and which we conceive to he well calculated^
not only to facilitate the acquirement of the first principles of
writing, but also considerably reduce the necessary expence at-
tending this highly useful acquisition, which is always desirable,,
and more especially when the improvement of the poorer classes
of the community is the object to be attained*
SchemB for preserving the Lives of Persons SkipwreckecU % G,
CuMBBRLATf D, Esq.-^PkU. Joum. No. 101?.
Mr. Cumberland states, that the mode of electing thi spur*
pose which he now olfers to the public, was suggested by observ<«
ing extensive masses of sea weed, called tang, on the westera
coast of England, floating into the hollow caves, on the surface of
the most tremendous waves. These formed a sort of green carr
pet, that undulated on the broken wave, and was never submerged,
although its surface was continually varying. On this natural
raft,' birds frequently lighted, and sat to repose themselves in the
same manner as if it had been a verdant lawn. On seeing' this
natural phenomenon, Mr. C. thought that a raft of this kind
might be constructed of otHer materials which would be capable
of Supporting men instead of birds. The result of his reflections
on the subject is,. ^^ that if each sailor in a man of war had a
^rk mattress, and these mattrasses were all linked together by
cords, such a float, capable of landing safely, even on breakers,
would be produced." Mr. C. also states, that cork shavings niay
be prociired for about eight penjce per bushel, and that a small
quantity of them is sufficient to support a man ; and therefore,, if
each mattrass contained enough for this purpose, and a number
of them being linked together at each corner, and thrown over«
board, would form an extensive raft capable of sustaining as
many men above the water, as there were mattrasses employed ;
and thus conveying them on the tops of the waves, and deposit*
ing them safely on shore, or even on the surface of rocks when
the sea retired with the tide. '
It is aho remarked, that all other rafts that the writer has
either seen or contemplated, possess this great defect of coming
on shore with too much force, which either disunites them, or
throws the people ofif; their wrecks are as dangerous as the rocks
upon wh'jch they strand ; and when they pitch, those on them
are in danger of losing their hold, and being washed off by thii
violence of the waves*
^
Obaervations. — We are always glad to second any invention
or suggestion which has a tendency to ameliorate the condition^
or save the lives of our fellow men ; and we consider the author^
410 Mr. Reever^i Patmitfir a method ofSpBttrng HUtM.
of such, as indispotably entitled to the thanks of the pablic. The
natural phenomenon which gave rise to this scheme of Mr. Cum-
berland, bad doubtless been frequently observed before, wiihoot
exciting any such ideas of its application ; yet this ought not to
furnish any argument against its utility. Mr. C. states his hav-
ing, some years since, communicated the subject of this letter to
the first Lord of the Admiralty, in hopes of haYing his scheme
fmi to the trial, but *' without producing even an acknowledg-
ment." Our examination of the subject, however, has induced
U8 to think that the scheme deserves to be tried, and that tha
motives of its author were sufficiently laudable to merit an answer
to his letter, even if it had failed of accomplishing the end for
which it was proposed. The flexibility of the apparatus would
eertainly act as - a preventive to its submersion : and with its
lightness, and consequent diminution qI momentum, would ren-
der the shock when striking any immoveable object, compara-
tively trifling to that of a raft composed of more solid ma-
terials.
SPECIFICATION OF PATENTS.
Jfr. Joseph Waeren Reveef/s Patent for a New pnd improved
Method of Splitting Hides, and Shaving Leather, communkaied
to him by a loreigner. Dated June^ 1810. Repertory ofAriSp
No. 103. Second Sertes,
Ti)r. principal parts of the machinery described in the specifl.
cation, and adapted to the required purpose, are the following :
Two cylinders *o{ metal, or any other hard and firm substance,
fluted longitudinally on their surfaces, or connected by wheel work,
and caused to move together by means of a winch, or any other
fiTBi mover. The distance between these cylinders is regulated
by screws, and at each end of the upper, there is a spring, the
reaction of which causes it to recede from the other when the
screws are turned back. A straight edged knife is firmly fixed
in a metallic frame; and when m its place, the edge is brought
into the angular space between the two C3dinders, and parallel to
their axis. In order that the knife may be properly disposed, the
frame in which it is fixed, is made with parallel sides to fit into
grooves in upright pieces, supported on the general frame upon
which the whole machinery rests. These grooves are also pro*
vided with suitable adjustments, by which the knife is properly
^xed and secured in its place. An inclined, or curved piece of
metal proceeds from each side^ of the flat surface of the kpife, so
ai to cause the parts of the hide or leather to separate and be car«
ried off after being cut* Another roller also revolves^ in form of
Mr. Reoerefs Patent for a metAod of SpUtting Hid^s. 411
the two cylinders ; ti^is is denominated the feeding roller, aud
bas its axis parallel to those of the forcing cylinders.
When the apparatus is to he used, the knife is properly adjas^
cd, and the hide to be split \vound round the feeding roller, so as
to present one end to the forcing cylinders, which are then to be
brought together by nieans of the screws, so as to take firmly h(M
of the hide. The cylinders then being made to revolve, the hide
or leather is forced against the edge of the knife, and shaved or
split, one part passing above, and th^ other below the knife. The
revolution of the feeding roller may be resisted by a friction lever,
or any other contrivance, and any degree of tension given to' the
hide or Uather as it is drawn off.
The principal improvements effected by this method, the pa^
tentee states to ** consist in the use of a fixed or stationary knife,
and in so placing and confining it, as to meel the hide or leather
before it escapes from the action of the forcing cylinders ; and
also in the construction of, and the manner in which a powerfifl
action is obtained from the forcing cylinders, whereby the hide or
leather, as it passes through, has not room to deviate, but must
necessarily be forced, and proceed right onward to the knife, and
undergo the splitting and shaving intended. By this machine the
hides or leather are split or divided into any thickness required,
and with great expedition ; and when divided or split, are left
with smooth surfaces, and free from any marks of the knife.''
Observations. '^We have previously noticed inventions for this
purpose, but none that will answer so well as this, on account of
the steadiness with which the whole operation of splitting is peir^
formed.
Mr Jonathan Varty's Patent for certain Improvements in the
Axle-trees of Carriages. Dated Septewiber 1810. — Repertory of'
Arts, No. 103, Second Series,
Mr. Varty states that in making the arm of the axle-tree, be
divides the bottom half of it into several parts, according to the
\veight intended to be carried. Supposing the under half to be
divided into three parts, he then cuts out of the upper two thirds
sufficient to take the bearing off those parts* so that the friction
alid weight rest only on a sixth part of the axle-tree. The bear-
ing part is left larger or smaller according to circumstances :
Sometimes two or more small rollers are fixed in recesses cut for
that purpose in the bottom of the axle-tree. The rollers turn on
their own axles in pieces of steel ; in which case the bottom pf
the axle-tree is flattened to thtow the weight on the xullers. A
groove is also made the length^ of the arm, on the toy side, ai^d
41i2 ifr. Wittim/i PaUntfit Maeime/ar grinding Halt, i^c^
amall holes passing through the axle-tree supply the axes of the
rollers with oil. The bush must be made with a cap at the
poiat or shoalder, or both, to contain the oil ; or this last may be
supplied by a pipe introduced through the shoulder washer. .These
improvements may likewise be used either separately or collec-
tively ; and where the box or bush is fixed, the formation above
described for the axle-tree is made in the bush. When hori-
aontal axle->trees are used, the arm of the axle-tree should be
made of the same size at the point as at the shoulder, and the
wlieel made perfectly upright, without any dish^
0^*enjflri(Mi*.— Mr. Varty's invention will effect a diminution of
.friction, and may therefore be advantageously employed in those
carnages which are intended for the conveyance of small compa-
rative weights; but when the weight is great, and the motion
rapid, the axle-tree will much sooner want renewing than those
which are made in the common way^
Mrm Charles Williams's Patent for a Machine for grinding or
cutting Malt, splitting Beans, and any other kind of Grain, and
various other Articles. Dated, August 1810. — Repertory of
Arts, No, 102. Second Series.
This machine, or mill, is composed of a cylindxical or conical
roller, made either of cast iron or any other suitable substance,
having grooves cut in it either oblique or parallel to its axis.
This roller acts against loose knives, made of hardened steel, and
screwed together to form a similar curve to that of the roller.
' These knives, therefore, admit of being taken out and sharpened
at pleasure. The roller may be put in motion by any proper and
adequate power applied to the axis which is made to project
beyond the supporting brasses, for that purpose, llie* roller thus
put in motion, acts against the cutters, while the substance to
be ground passes between the last and it ; the distance being regu-
lated by a screw adapted to the purpose. IVo levers also act
against the bearing brasses, both to keep the lever to its work, and
to assist it in rising when any thing too hard to be cut gets be-
tween the roller and the knives, and would therefore injure the
one or the other ; but which is by this means suffered to : pass
through ; after which the rollers will fall into their proper place
again. Two weights slide on these levers for the purpose of ad-
justing the force which acts against the roller ; and the whole ris
mounted on a carriage. A double.wired screen is also annexed
for the purpose of taking the rubbish and dost from the. malt or
other-matter; the upper wire is sufficiently coarse to-Ul the malt
JMr. S^orier^i Patent far an Jpparatusfot working Pumpt. 413
pass through, and the lower one to take oat th6 do^t. These vrith.
tpoats to carry off the refuse, and regulating sluice for feeding
the milfy are the parts which constitute this apparatus.
Obstrxfations, '^In examining the specification of this patent,
we have been at a loss to discover what advantage th^ patentee
expects to result from the use of his machiheVy. The object df
thus preparing malt for brewing, is to render its saccharine and
other valuable properties susceptible of being as easily and conu
pletely dissolved as possible by the, liquid in which it is immersed.
The question, therefore, is simply this, whether the cutting or
the bruising process is more efiectual for this purpose? As far its
our experience extends, we prefer the latter.
Mr. Edward Shorter's Patent for on improved Apparatus for
working of Pumps, Dated March 1803.— ilgier^ory of Jris,
.No. 101. Second' Series,
In this improved apparatus, an arbor or axis is fixed near the
stern of the ship, in nearly a horizontal position, and in the di«
rection of the keel ; having one of its extremities either project,
ing behind the ship, or so placed as to admit of an external ap-
paratus being fastened to it. The other, or foremost extreinity of
this axis or arbor, is cpnnected with the pump or pump's, by any
of the well known means.
The apparatus to be fixed to the hinder extremity of this axis
consists of a fiy, made of wood, or any other suitable materials,
like the sails of a windmill, or smoke-jack, and drawn through the
water by the progress of the vessel ; which causes the re-actioa
of the water to impart a rotary motion to the fiy and axis, and thus
work the pumps. If the ship be at anchor in a current or stream,
the direct action of the water produces the same effect. The fly
is connected with the arbor by' means of a spar, or chain of me*
tallic rods, or a rope, and flexibility is given to those parts where
it may be deemed necessary, by shackles, links, universal joints,
or any other well known contrivance, which will not prevent the
due communication of rotary motion. The same rotary mo-
tion |may also be effected by exposing, a fiy of proper dimen.
sions to the action of the wind instead of the water. The sub-
ordinate parts of this apparatus, must necessarily be adapted to
the nature, construction, and number of the pump« to be worked,
as well as other local circumstances, which will be easily deter-
mined by any competent workman. *■
OA5t'ilpfl/i£m5.-r-This contrivance is calculated to save con si'
d(BrabIe manual labour ; but when put in motion by means of tke
No. 26.— -VOL, \u 3 H
Mff'n i^ion tbrougib the water, it .will,, in s^j^*^ dftgil^ affiy^
Vffjf |upgf^9; whiU on the co^rary, if win^ be e;np)oyed a^ tbf
moving ageot, t)ie apparatus may be so constructed as to ajss^f
rather than retard the motion of the vessel. We, however, do
ffffX peTQtiye any reason why these two methods might not hQ so
]f^in trivet a3 U} either act together or separately as c^rcmmsl^ce^
jn[Ujght render nece&sary.
-Hak
f
\
'i .
Afn idsBFH Aktiiont Berrollas'# Pa/^ent for a fVaming
Watch upon a new Construction, . Dated May 1810.-. Wkh
Observations by the Patentee, — Repertory rf Arts^ No, 101. Se-
The patentee states that tbe inside movement of this warning.
watcb is not different from that of a common watch, excepting
'ft barrel, which is fixed by means of two screws on the underside
of the top plate, as near the main spring as possible. " The
*arbor of the side barrel is made in the same manner as in a clock-
*A»atch, has a brass wheel with 6o teeth, with a steel wheel fixed
to it ; which steel wheel has 33 teeth, cut like a racket, which
catise the hammer to act. This hammer, placed between the
main and warning barrels and side hammer, strikes on a bell«
spring, which is fixed with two screws on the* pillar plate. The
spring in the warning-barrel is woupd up five turns, which occa-
sions the hammer to give one hundrec^ and sixty-five strokes oa
'the bell-spring. Opposite the hammer is a pinion with six teeth
"which act in the arbor-wheel. This pinion is planted on one side
of the upper plate, and on the other, in a bar on the back of the
'piUaf; ori the side pinion is a wheel with forty-five teetb, which
'Wheel acts in a pinion with six teeth planted in the bar on one
side, and on the pillar- plate, on tbe other; on the said pinion is
a wheel with twenty teeth, like a racket, which acts in a pallet,
planted in the pillar-plate on one side^ and in a bar on' the other^
tvhrch form all the warning parts.*'
The motion part is the same as that of a common watch, and
the detent of the warning, as well as the '' description of the
outside of the> watch,'' is illustrated with figures ; and as these
can not be easily understood independent of them, we must
refer the curious reader for further information to the number of
the Repertory which is specified at the head of this article.
Irr his observations, the patentee reQiarks that a mechanism
performing the part of a monitor, by reminding us of any parti-
cular time we may wish, is one of the most convenient and useful
objects that can be desii^ed i and even to many people it is abJXH
Mh Ml^herfi- Paieht fSf tigfyifrg Biill^gg w^gat, 4M
VatHiiy ritc^swry. thfe vtmty of thirf friVcntrorf wa% foftg' tJifi^4 '
rfPfiV^diat^a, ai!r<f an aftttmpt tftdde to patlli% ififeA- ialt6^prwitik€€^
ftfit hr table clocks, trnd afterwards into \»iltche». Fi^^Cfci^e,
however, are to* be met with ; and Mr. B. says that oW &xnrkYttth
tSotl, the reasons whieh both prevented thetri frofti b^oihing^^
i^tk\f and being appmved by those persons who iiiadfe tfae' of
tireVn, are easily {)efceived. He al^o enftiitfiefat^ ievferdl iii^M^'
v^hierices and 6efetU which conlrrbirted to this «nd, aiidtbtci
iAiittvtt that *^ th^ newly invented wafn'tng*watch does ai/s'ft^
lAi these defects; both the moven^ent aOd the wairnlng ciua' M'
^^hnd up together, and the latter a^ lon;^ bef6re hrand a^yOuT
please. To set rt to the hour you wa!n<j there is liot any n^cfd 6f'
opebhi^ th^ case or of tOl!^hing tlie hand. The mternal cotisfti^d^ •
tion ts ako extremely >^hip!e, as- th^rfe is* oiily oile -^he^l diid^-
itii' barrel in addition to tb« common movement, cohseqae&tly i&A'
vFMel)5^ are not croslv'ded for want of raorri.* The detent is ah ^fi«
th^ n6>^ rnventTon-, atid has riot any conhmonA.cation with ih€
movement when the warning is not scrt. One sfh)hg obj^liOlit
that has been urged Against modern tflarm-watchtis is' thsCt t&e
86und Of tbe bdl was not Suffitientiy loud to be he&i^d ; btrC Hmtf'
are so' effective that the^ can be h^rd in one lloot* -^hWt bun^ Ap[
ih another/' This invention deprives' the Wearer' of anjf fear M
dferangrngit, a!nd will aict at plfea^ttVe* during the^ Whole day witft^ *
Otit 6itb'ei^ opening the' caste ^or '^^inding it afiish ; and eati be d^'
pfrftd t6 <iratches of a=oy pi^ice,
OSs^rvatums, — Wi hate atready noticed, rft pag^ S66,-, bf otti?
5ilh ^olnm^, Mr. Berrollas's Pateiit for a very simple r^peAtiAg
\^atch ; and we regard the present invention a^ attbth^i' ^0^<ie89fal
exertion of his mechanical genius. The utility of thift sdhjeet,
the simplicity of the mechanism, and the consequent stnall ex«^
pKhse, w^ trust are sufficient to obtain the patented such a sMr«
of public approbation and encouragement as will prove a libiraf
r^w^rd for Eis ingenuity,
■ . 1 ftii t
iH iliill rMii'i^
jjf. John MAiBUU'd Patent for an Apparatus /or makif^cdribntiU
e'd tiydrogevi Gas\ and applying the same ti/i ligktih'g Baildiy(gi\
..^c; Dated May ISW.^'Repertdfy of JrtSf Ifd. tM. Si*
cdttd Series,
The reservoir ig a cylihcler of cast iron, or other SuitaMe mtf-
jt^rlal, surmounted by a hemispherical dome: it id ornamented'
v/iih six pillars, one of whicTi serves as a chimil^;^, and the others
cover the pipes hy whicli the reservoir ii filled Withi water anrf
gas^ or emptied of those fluids. The cylinder is'plad6d upon a
jcifcutar ba«e, ^l^ich contains the furnaCe \^ifh it^ retort, as" aKof
4m Mff* MMmi-9 JfftKNtUafor making em^mt^ted Hjfdrpgen Got,
m cMMiensing pit for the tar aod liquor,' and as it is wider tha^
the reservok, four regulatiog boxes are placed arouod the bottaoa
of the latter, so as to preserve an uniformity of aspect^ and com*
hiae the useful wijth the agreeable. > , c-
Contiguous to tbis apparatus, and rather higher than the tQ{^
of. the reservoir is placed a cock which supplies the water that
ia ftecessary, which runs into a box, with a notch on one side,.
8p th^t the fluid is always kept at one certaui height* One Qp
T^(u» syphvps are placed on the side of this box, and discbarge.
t£e water into one or more funnels, from whence it is conveyed into
imMpe<that desccAds to the floor, then runsup oae side of, the.re^.
Sficv<oir, penetrates its suBunit, aad goes down its cenl^r n^urly^
to the level of its base. ^The water thus conveyed,, expels )th4(
aftfQOSpfaeric air in the reservoir, which escapes through another
tube,- 'Opej^ing near the top of the .vessel, passing down its side^
aqd serving afterwards for the conveyance of the gas. The yr^XvK
is then stopped, by letting a plug fall into the funnel, i^hich rais-
if^ the water in it, stops also the syphons* , •
j.Xhe gas is. conveyed from the retort into a funnel standing upox^
a^east iron pot used for collecting the tar. From the top of this
pot it passes through a pipe to a washing box, where it. eaters at
t|ie lower extremity of ^p inclined plane furnished with edges on
tl^ under side, which multipUes the points of contact with the
w^terifl whichr th^ plane is immerged. From liie upper extre*
mity of this plane, it passes through a pipe which runs \^]f the
side of the reservoir, penetrates its summit and passes dowii the '
Cfoter to the level of its base. The gas issifing. from this.p^pe,
ia strained through a flixlge - perforated with, a number of smal)
holes, and then dispersed through the watei* by strikpg against
t^ sloping side of another flinge, also soldered to the l^ipes in
the center.
To expel the gas now collected in the reservoir, the plug in
the funnel is again raised by a string, and the water permitted to
run into the reservoir through the abovementiqned pipe, and thus
cause the expulsion of as much gas through a pipe openfng m
the upper part of the reservoir, running down its side, and hav-
ing a safety box or sphere at the lower extremity, from whence •
the gas is again carried along the under surface o^ an inclined
plane^ with ledges as before, and- discharged' at the uppW extte-
mity of the jplane into the main pipe, or leader to the lamps.
The fourth Kok is used as a regulator, and might be placed any
where upon the main pipe ; it consists of four sides and two bot^
toms, to the^upper of which a short pipe from the main is fixed,
and also another reaching downwards nearly to the under bottom,
the space between the bottoms is filled with water, which when
the gas becomes too atrong in the main, is forced up the small
pipe above the upper by which means a water joint is fonnedj
with an inverted famel; wImd the srater.isali akove^ tfat extm
gas follows by the tame tube, and escapes throogh the funnel.
Lead and iron tubes are nsed wbei^e they are indispensible, but
tM QBConotny is the princifml object, pipes of wood, covered witbr
the guts of animals, and coated with varnish, or glass tubes, are
Also used. . . \
The ^ater that is expelled from the reservoir when the gaais
produced, passes through a pipe, opening near the bottom o£
^e reservoir, thence passing up its middle, and its side, is con-
veyed into a box, from whence it passes over a division into the
waging box, then into the safety box, and from thence to the
condensing pit; from the upper part of which it flows by a pipe»
and falls into a funnel that is inserted into the pipe coming froa»
the bottom of the tar pot, and which is kept shut by a cock, and
thus keeps the fluids in the pots at one regular heigl^t, while the
remainder flows over the edges of the funnel, and is carried off. .
When the retort cools, the atmospheric air passes along th^
tar pipe, through the liquor, which is then drawn iiito the const
over the pot, and fills the vacuum.
Observations^'^The several parts of this apparatus are ingeni^
ously contrived, and have such a mutual relation to each other^
that the entire view of them can scarcely be exhibited by words
alone. Xhe apparatus has also a handsome appearance, so that
it may justly be esteemed as one of the best that has hitherto
been given. , V .
' The wooden pipes for the conveyance of the gas, must be.<eco«
nomical ; but we do not see the necessity of using the intestinea
of animals, as we 6boi\ld suppose- that varnish alone, if a sufji*
ent quantity were employed, or even painty would be sufiici^t U^
confine the gas.
0^1
Mews, WitLiAM Su AXES PEA R 6(ff^ Thou AS Obl^vl^s Patent for
a new and mprwed Method or Methods of Manufacturing Glass
. or Paste Drops for Chandeliers, Lamps and Lustres. Dated
Jufyf ISlO.-^Repertori/ ofAHifNo. 101, Second Series.
In this new method the drop is iirst formed according to the
usual mode, and then the part inteiid'ed to receive the metallic
lo^p'itf remelted, or %o far softened by beat as to admit of the lobp
or piece of metal being worked or pressed into it; which ia.then
• carefully inserted by means of a pair* of pincers or oiher proper
tools. Or the loop may be inserted in the mould or die, and fi\^A
in (he act of moulding ; but these patentees prefer the former me-
thod as being most secere. The metal which they prefer for the
loops is either silver or copper^ and a notch is sometimes cut ia
^# ,
41 S Mr. Hooper'i Patofifor a TkeriMnUvrfir Qvtmi
Aat psrt of tbe loop^ iagertod ia the glass, but iMt is not esieiH
tiaL
• • •
mtmaaasEssKEBSsssssssstsessBSBsssasaesms^Bsata^
J/r. Stephen Hooi^^k's patent for a Thermometer^ or M(fckinA/or
' ascertaining the heat of Baker's OvenSf and various other pur-
poses^ Dated February^ ISO9. Repertory of Arts, No. lOtr
• Second Series.
Tins thermomttcr h generally constrocted of a bra»s tMS
ktsA a wooden rod, and of any convenient kngth and diameter to
fttit the purposes for which it is to be used. The length of the tnb^
h equal to the length of the oven to which it hXo be applied, anti
Generally about an inch and a quarter in diameter. Thcr6d is tfiade
5f fir or any other straight grained wood, and of susb a thickniess
as to slide easily into the brass tube ; both being nearly of the
feme length. Thty are then firmly fix^d together at one end ;
St) that when any expansion or contracti()n take^ pUc<j in the
tube through Tariation of temperature, it is indicated by a -s^afe^
on the other end of the. rod*. Btil a? the divisions on this scale
Are too mintite to be eithet* easily made or distiwtJy observed,
the patentee prefers a scafe with largeV- division^, constructed,
itccording to the method cofhmonly employed iri making the
scales of pyrometers } and then a' hand or itrd^x jyoints out ths
degree of expansion or heat on a circular plat^ properly divided*
Tbis'index and plate is fixed to the wooden rod; the former of
fi^hicli is attached to the axis of' a pinion, and tifrned by a i-ack
<jn the end of the tube.
Mr. Hooper then describes iha iftefhod of using this imiruin^mif
ita the following manner. ** I caos^ a chani^l or hole to b^ n^ade
in the brick work about six inches below, and pirralltl to the
bpttom of the oven, exjLendiu^/rom tjie mouth to the f^^rther side ,
thereof in such a direction as that a vertical plane passing through
the said channel or h9le, shoulcl nearly bisect thf oven and door^
The thermometer is introduced into the said hole, leaving the
index exposed to view below the door of the oven ; or 1 cause. the
said channel or hole to be made in any other convenient part of
the oven as may be required.**
< ObservatioM.^'^The construction of this instriimctn is simpie^
and we doubt not that it 5till be fonnd sufficiently accurate to
xnewer the Qeefui porpoee for which it was iaveiited.
Mr. W«^^ ^ff^U^ p^p)npw|^^*t« Ojm^^. 4}9
mmmum
Mr, John Okions's Patent for a Machine Jbr thrashing Corn and
■ athtr Grain, on a new Construction, Dated May, 1810. — Re*
• pertort/qfjirts. No. 101. Second Series, '
• The natut'e of this machine i« such as not tovadmit of a brieSf
ttfi^ perspicuotis' description independent of figures : and we are
lti«FefoTe under the necessity of referring the curious reader to
the specification itseW; only observing that as far as we are ^ble
to judge from the'sivort description which the patentee has given,
it appoare to be well adapted to the intended purpose.
Mr. Fredekick Albert Wiksor'* Patent for Impr(roem€nti in
bis Oven Stwpej or Apparatus for carbotiising all Sorts oj ram
Fewel^ SfC. and for extracting thp OUt Tar, p^roHgn,om Adds
and ammoniacal Coal Liquids, and for extracting and refining (Uso
the inflammable Air or Gas. Date4 Feb. 180P. — Rept^rtorjf
of Arts, No. 103. Second Series.
livery )^ind of gas light apparatus now us^ed is on. the principle
of an enlarged charcoal furnace, (of ^hich there are plenty about
London,) connected with large gasometers* The oven contaiAing
letorta full of wood pr coaU in the centre, and a fire of raw coal^
is made to play around them, by which contriya/ice, atov^ half
of the heat is necessarily lost in the brickwork. The gaeometers
or gasholders are largjB reservoirs, in which the gas is st^fTered to
accumulate to a very great hulk ; which besides the danger, pre^^
yenU it from being thoroughly retinejd ; wrh^ereas in the pr/e^eot
ipparatuSy tbe gas is so inEnitely divided ipjto minute pa;rti€l§#
that all the tar, oil, bitumen, and ammoniapal liquor must be
precipitated before combustion.
For this purpose, the coking stove may be ipade of iron o.r
any other fire pro.bf material, aqd of any s}^ape, provided ijc OC'*
cupies only from l-4th t9 l-3d of the area of the etove, andk
is to be perforated vertically with a cylindrical or other formed
£re-place, in which the refuse coke or coal is xo be burned, and
by this means, a great saving is produced in the expenditure of
of raw fuel, as the heat generated in the centre expands in all
directions, and is inore equally distributed among the coals. By
ti^is ^ethody I-S of a bushel of refuse coke no^y g^perate sufii-
<;ietit heat to carbo^^sie a wl^le bushel of coal, so as to prociuce
a bushel and a half of good coke ag^ip, ))esjde% 6 .or 6 lb* o^
oil tar, 7 or S lb. of strong ammoniacal liquor, and from 220
to 260 cubic feel of pure gas, according to tbfr quality uf the
coal. •
The fire-place may be constructed so i%s to pass in all possible
420 Mr. JUmor'i Patent far mprofOemtfUs m U$ (hen State*
directions through the fuel to be c^booised; and the longer the
circuit it makes through the coal, the sooner will the carbonise*
tion be completed, and the better the quality of the products.
Succession stoves may also be constructed, divided into several
compartments, closed with iron covers ; from each of these di-
visions a separate flue carries the smoke to the main, and this
flue is to be shut with a cock, or valve, during the time that the
compartment is being charged with raw fewel, or the coke being
taken out The coiiipartments may hold, from one peck to one
sack or more of coaU, and being charged and discharged in suc«
Cessioh, the operiition of the furnace may go on day and night
without any stoppage. In them good coke may be made even of
the refuse or siftings of coal, if forms of iron, clay, or wirework
be filled with small coals and placed in them*
The hot smoke from the stove is led by a pipe either through,
or by the side of the fire-place into the lower chamber of the
condensor, where it is minutely subdivided in winding round and
passing through several side partitions perforated with small
holes t from hence the smoke and gas pass upwards on -a surface
of water saturated with lime, and from thence over three, four,
or more surfaces of lime-water, until, on being examined by try-
ing pipes, the gas is found to be quite transparent.
The top of the stoves have upright ledges, or shoulders, with
alembic covers, to serve for evaporating or distilling tar, &c. by
the same heat, or to form a sand bath for any desired purpose, or
they may he formed into a pan or kettle for boiling water, &c»
by the hot smoke before it passes into the condenser. These
condensors may be made of brick or stone work lined with lead,
or of iron, &c. but the cheapest are made of wine casks cut in
half, with several bottoms made of wood, &c. to hold several sur-
ftices of lime-water.
Should the coal be of *' of a strong quality,'' a small quantity
of slacked lime may be thrown at the bottom of the stove, and
sprinkled over with a little water, the steam of which will rise
through Ihe coal, impregnate itself with the smoke, and thus puri-
fy it from the disagreeable odour. This is better than to mix
lime with the coal, as that affects the quality of the coke.
The gas roust not be lighted too soon, as the blue flame will
frequently be forced inwards by the superior weight of the atmos'
phere, and cause thjs gas to explode with the rapidity of lighten,
ing. The same effect may take place towards the end, when the
elastic pressure of the gas becomes inferior to that of the atmcts-
phere, and therefore it is dangerous to let the lights burn out of
themselves.
The principle of applying the fire in the centre may be applied
to heat^^ater or other liquids, ii^ wooden casks much s6oner than
Bxp$rimenti oh Socot/ine ani Hepatic Aloes^ 421%
In the common mode r and tubes may be carried through the fire-
place, 80 as to supply heated air to roohis or even whole houses.
.. O&wrptf^ftww.-— The carrying of the heat through the centre of!
the substance to be heated has been attempted by several specu-
lators, but as the apparatus must be more complicated thaa
usual, and the inner surface liable to calcination, which would,
require frequent repairs, it has in general been abandoned. Th«
pi-eBent patentee goes a step further, and generates the heat in
the centre of the coal to be distilled. Although this practice may
have the support of theory, we doubt whether it will succeed bet-*
ter than the old method of surrounding the distilling vessel with;
fire or heated air. When the walls of the furnace are sufficiently
thick, the quantity of heat lost through them is but small, and
the radiant heat of the masonry has a more considerable effect^
upon the contained vessel thtgi is usually, imagined, provided th^
vacant spac6 between the walls and the vessel is properly pro«
portioned. ♦
The only novelty in the succession stoves is merely in theit
application to the production of gas lights, the principle of a dou«
hie set of vessels, for the purpose of one set beii^g cleared and
prepared while the other is in use has long been known.
The gas is purified by exposure to lime water, whiith is a varlatioa'
only from Mr. Heard'» patent, see Ret. vol.iii. p. 83. in which tho^
gas was exposed to lime in substance, and this method of Mr*
Winsor we conceive to be in some measure an improvement, but
more expensive and inconvenient in respect to the requisite appa^
vatus. Mr. Heard also sometimes mixed lime with the coals ta
be distilled ; which spoiled the quality of the coal ; the present
patetttee merely throws moistened lime upon the bottom of tht
. stove ; which tan never be so effectual.
wmamaaBmateataassemBBssEBsssssBsssaseBam
ii^
CHEIMISTRY.
Experimenfs en Socotrine and Hepatic Jloes, By Messrs. Bovii<^
LON — Lagrange, and Vogel.— ^/m. d& Chimie^ vol. 68.
These experiments were left off as soon as it wa^ known that
Mr. Braconnot had published a paper on the same subject, and
it was not intended to publish them ; but as he, and also Tromnds*
dorf has not noticed some phenomena, and there also appears to
be a difference of opinion on some points, a few experiments are
here related.
A chiliogramme (2 lb. avoird.) of each kind of aloes wer^
distilled by a gradual heat. Water and oil passed over, btt no
traces pf gallic acid, or carbonate of ammonia; towards the end,
the aloek itself siiblimed ii\ a bfilUafit black form« fha.watei*
VOL. Vi.— iro.^6. 3 I
^2 Repeiimexis on Saiotrini mi Hepeiie Ahm^
that came over turned blackish brown with sulphate of ireii, hut
ihe colour is not comparable with that given by gall nuts. So-
Ititlons of lime, barytcs, or strontian do not alter the colour,
whereas gall nuts forms with them blue, green, and ros* precis
pitates* The water, however, of hepatic tildes is sensibly am^-
Bioniacal, bnt that of Socothne aloes contains only a slight trac«
•f tnat alkali.
- In another experiment, each spseimeit of aloes was mixed up
with a quart of water, and then distilled. The Socotrine aloes yielded
Kquor not acid, of a very agreeable smell, with y ellowish green oil
fwimnitng on it, whose odour resembled that ot melilot. This wa*
ter deposited a few flakes after some time. Hepatic aloe? yielded
• water whose smell was rather nauseous, approaching to that of
^russic acid, and no traces af oil were to be found. By them
aaarks, the two species may be distinguished.
> Braconnot says that aloes is totally soluble in eoU water, and
that the least portion of it \g perfectly similar to Che aloes eiii»
ployed. Water at 8^ Reaom. was poured upon Socotrine aloes*
tnd after remaining upon them for some time, was poured ofl^
and this was repeated until the water that had renutined upon tb»
aloes for 24 hours acquired neither colour nor taste. The first
. liquor was very brown, but earh succeeding portion was lighter
coloured* When the aloes wis entirely exhausted by water vt
t* the mass was worked between th^ lingers under a small. stream
ti water until a soft greyish very elastic mass was left, whik:k did
tiot stick to the fingers when moist, and was totally di^^ent from
the substance obtained from the aqueous solution -of aloes bj*-
tvaporaticei.
? Aloes dissolved in cold water forms a solution that lathers vetji
much; it is precipitated yellow by all the acids, and by the salte
^hich do not contain an excess uf alkali. Many metallic salts
produce precipitaies more or less coloured. Sulphate of iron, ad
sniniinum, or ad maximum, throw down a blackish brown pre»
^ipitate, which is very diderent from that obtained by gallic acid;
although Tromms Jorf probably inferred the presence of that acid
in aloes from this precipitation; but many juices of plants and
medicinal extracts ^ield the same kind of precipitate^ and, the
concentrated infusion of saffron is coloui'ed black by this sfilphHtc;
yet saffron is not suppoied to contain either gallic acid or tannin.
These precipitates are all soluble in water, and are formed ei-^'
iher from some resin that dissolves by means of the other sub*
stance, or rather from the watery substance of the aloes itself^
ibr the volatile oil of aloes dissolvt^ in water is niH blackened bji
sulpha<te of iron,' or rendered turbid by the other lasetallic saits«
Th^ watery solution evaporated to dryness yields a very-tramu^
]^ent brownish mass, breaking -like gla^s^ ftisihle by a genth
jbesity yielding n. gold y^Uens pMderi very M^iert and^hamif Ib^
EapermenU •n Socotri^eani Hepatic Jloa* 4tf
ftndl of volatile oil of aloes. It is soluble in water or alkohol^
^ttt scarcely in rectified ether. Go the other hand, resin of aloef
yields a grayish pawdex« not soluble in water at 10°, but solubla
in alkobol and eth^r. The alkoholic solution does not lather, as
it done by that of the aqueoqs part in the same solvent. Th«
aolatinn of th^ lesin in ether is precipitated by .water. But thg
action of water is alone sufficient to distinguish them ; for ou«
•f 'these substances dissolves in it quickly, and ihe other may bt
kept in it for som ttime like the gluten of wheat.
Fourcroy and Vauquelin have discovered that gluten is slightly *
soluble in water ; although that liquid is .used to separate
it from the other substances in flour. Neither can fecuia, not*
'withstanding it is insoluble in coiti water, be kept in it withoitf
altering it. In like manner the resin of aloes oomtnunicates t9
water, after some time, a slight taste and some colour.
The extractive matter ot aloes is easily soluble in cold nitric
#cid at 36^ hydr. The solutK^n is green, and is scarcely ren4
dtrcd turbid by water, and soon becomes clear : whereas th4
fesin is more difficultlv dissolved, the solution is red, and let4f
fall, on adding a Uttle water^ a resinous sticky matter, which ia
iBSolttble in water.
Trommsderf analysed aloes by boiling water ; but there it
veasoD to think that the resin does not entirely separate on tb#
ioltttion becoming cold. One hundred grains of Socotrine aloet
were treated with water at %^ Reaum. When it was exhauste<i^
the insolttble residuum, on being dried, weighed 3^ gr. Henc#
^cotrifie aloes contain 68 per cent, of extractive matter^ an^
52 of restn. Hepatic aloes was also found to contain 52 per
^ent. of extract, 4^ of resin, and six of some matter insolnblv
either in water or alkohol.
Kitric acid heated with aloes produces a fine yellow powder, «r
tery small quantity of which being mixed with ^ater communi*
cates to it a magnificent -purple colour that stains the sMii fo^
several days, particuiarly if an alkali, or alkaline earth was pre*,
viously added to the powder. When this powder is distilled, it
•eon meks, and immediately a slight explosion takes place, and
a deep red vapour is expelled, which is difficultly condensed. A' '
yellow^ vtry acid, bitter liquor, smelling like Prnssic acid, is col*'
kcted, which seems to be prussiate of ammonia ; ay it emit#
ammonia wheif potash is added to it.
Oxymuriatic acid gas was passed ttirovigh a solution* of aloet
in cold water ; the gas was absorbed in great qisaotity, the liqnor
Became yellow, and formed almost entirely % whitish yellow
^oi^lum, which soon turned brown. When washed, the coa^
gulum was very elastic, insoluble. jn cold water, easily soluble in
•Ikohol, and the solution was precipitated by water; to tliat liii'
4aUracliv« of Ac jftloet was in iooit iitff%% reaiai^ed. .
4!4 On Ci/stic Oxide,
Aloes then is not a homogeneous substance, as Braconnot 8ii|h
posed, but consists partly of a mattei" which remains when tl>a
aloes is washed wiih water, and approaches to the nature of re.
tins, and partly of a soluble matter, analogous to extractive, but
differing in a few circumstances ; on which account, HermbstadI
and some other German authors propose to call it saponaceous
matter.
Oa Cyitic Oxide, a rtno Species of Urinary Calculus. By Dr. W»r,
Hyde WoLLASTON. — Phil. Trajis. for IHIO.
In a former paper (Phil. Trans. 1797)> ^ye kinds of urinary
ealculi were noticed. 1. Lithic acid, since called uric acid ; 2f
Oxalate of lime, or mulberry calculus ; 3, Phosphate of lime, or
l»one- earth calculus; 4, A mmoniacal phosphate of magi^esia ; 5^
Fusible calculus, which consists of the two last species combined*
But since that time two specimens of another species of calculi have
been discovered, one of which was taken from the bladder, of a
boy five years old, and was covered with phosphate jof lime; the
other was extracted by the usual operation from the bladder of
ii man 36 years of age; it weighed when entire 270 grains*
These calculi are more compact than the triple phosphate of
xnagnesia, they do not consist of distinct laminse, but appear as
oae mass confusedly crystalized, of a yellowish semitransparency,
and with a peculiar glistening lustre. They yielded 0:R distilla*
tion, carbonate of 'ammonia, a heavy fetid oil, and a b}acL spungy
coal not so bulky as that left by uric calculi. When buroed by
the blowpipe they may be distinguished from uric calculi by^
the smell, which at no period resembles that of prussic acid, but
bas a peculiar feetor in addition to the usual odour of animal sub<»
stances.
^ They are not soluble^ except in very small proportion, in ^ater,
alkohol, acetic acid, tartaric acid, citric acid, or saturated* car-*
bonate of ammonia; but it is soluble in muriatic acid, nitric acid,
sjilphuric acid, phosphoric acid, oxalic acid, potash, soda,ammon
Ilia, lime-water, and even the saturated carbonates of potash or
soda. So that carbonate of ammonia is best for precipitating
this substance from acid solutions, and the acetic and citric acids^
for precipitating it from alkaline solutions ; bat the tartaric acid
may occasion error by forming a supertartarate with the .alkali.
Its combinations with acids crystallize in spicula radiating
from a center, which are ag^iin soluble in v^ater UQless they l^a>^A
been overheated.- The muriatic salt is decomposed b^.:Jihe heat;
oftboiliiig \yater. The combination with nitric acid turi^s brown,
and grows gudually jda^ker .vi^ilii is kh^ki w ox^ic ^<;id i4
. Ott Cystic Oxide 4M
l^rodoced. Its combinatians with the alkalis leaTe small granular
crystals.
When a hot solution of potash was neutralized by distilled vi^
negar, this substance separated during the cooling of the liquor if
minute crystals, some of fiat hexagonal plates, which perhaps are
owing to some remains of the aikati.
This new calculus appears, from its ready disposition to unitQ
"with either acids or alkalies to be an oxide, and as it has not yet
been found any where but in the bladder it might be denominated
cystic oxide.
The acid sublimed in the former examination of the mulberry
calculus was supposed to originate from a partial decompositioa
of the oxalic acid ; but as oxalate of lime does not attord this
ftublimate, it probably was some uric acid contamed in the caL*
cuius.
In order to ascertain the presence of phosphoric acid in th^
triple phosphate pf n>agnesia, the prefeicoce was given to th^t
experiment in which nitrate of quicksilver was employed ; but as
the whole of the phosphoric acid is not precipitated by thi^
nitrate, the addition of sulphuric acid will not produce sulphate of
magnesia, and therefore the magnesia cannot beobtained sepa^rate
by this process. . \
. A calculus from the bladder of the dog is said, in the Philoso-
phical TransuctioQfi, to be composed of superphosphate of lime
and phosphate of ammonia, but its appearance when shewn to
the society was against this conclusion. A portion was there*-
fore obtained. It was almost totally soluble in distilled vinegar*
Acetate Of lead in excess precipitated the whole of the phosphoric
^ acid. Sulphuric acid separated the excess of the lead, and formed
sulphate of magnesia, fron,i whence the acetic acid, sulphate of
ammonia, and excess of sulphuric acid were expelled by heat, the
residual sulphate of magnesia being redlssolved in water and
crystallised^ weighed rather more than the original portion of the
calculus. There is every reason indeed to believe that so soluble
W ^ a salt as superphosphate of lime never forms an urinary con-*
eretion.
The white matter voided along ^yith the dung of birds was
found by Vauquelin to be principally uric acid. In the dung c^f
the goose, feeding only on. grass, this substance fornied about
l«200tb of the mass; in that of a pheasant kept in a cage and
fed only on barley^ about K14th. In that of a hen having free
rangp, it was more abundant, and combined with lime. The
solid excrements voided by a hawk bears but a small proportion
to the uric acid left by the evaporation o{ the urine. I'he gannet
feeding solely upon fish, ^eems to evacuate nothing but urine, for
4t leaves only uric gcid when dried* Frgm which^it appears that
M( On OttyBnvmiie AtuU
ftnom Ml^tct to uric calettli» and gimty persmm wiieae nrhiiftaU
ways conUuDs an excess of uric acid have some reason for pret
IsFruig a vegetable diet, Uil tliat tbe preference g,tven to fiah is
yrobably erroneous.
• msssBsaaaBSSsssssgaBsssassatmmmmmmmmmmmmmmmmBm^B .
Ob Osymuriatic Atid^ and on tie Element % of Muriatic Acid; wtk
tome Experimenti on Sulpkur and Phosphorus. By Mr. Hum*
rawLY Davy.— PAi/. Tram. for 1810.
ScHKELE considered oxynrariatic acid as muriatic acid freed
froK» iiydrogeDi and denominated it» of course, dephlogistieated
aivfiatic acid; Berthollel a short time afterwards concluded it
WW composed of muriatic acid and oxygen, and this opinion has
keen almost universally adopted. Henry obtained hydrogen from
■wriatic acid gas, and thought it came from the decomposiUon of
water.
' When potassium acts upon tnnriatic acid gas^ more tlian one
Atrd its bulk of hydrogen was produced, and no muriaitic acid
cidi be obtained from oxymuriatie acid, or the diy muriates, mi*
Ih* water or its elements be present. *
Gay Lnssae afriH Thenard deduce from their experiments that
vmriatic acid gas contains l-4th of i<s weight of water, and thai
•xymoriatic acid is not decomposed by any substances hot by*
jrogen, or such as can form triple combinations with it.
That oxymuriatic acid gas does not cnntaia oxygen seems eviv
dsnt from charcoal not effecting any change in it, or the mnriatie
■eid gas, even when ignited to whiteness by the most powerful
friyantc batteries.
, Oxymuriatic gas is absorbed by tin if gently heated, and m
Kq«id similar to that of Libavius is formed ; on admitting ammo^
snacal g^as it was absorbed with great heat, no gas was generated,
■nd a duU white solid substance producing dense pungent fumes
fcf volatilization was formed, so that it forme a new eombifiatioD
wttb this substance.
The solid substance formed by oxym«rria«ic acid^gds aeting
vpon phosphorus, absorbed ammoniacal gasj produced much heat|
and formeda white powder, which bad no taete nor srnfell, and
was not acted upon by water, sulphuric add, nitric acid, muriati€
SKid, or a strong ley of potash, neither was^ it altered by being
Ignited to whiteness in a platina tube. When indeed this ppw.
der was made red hot by the flame ef a spirit lamp, it yielded
feeble indications of inftammation, tinged the iume yellow, and
kft phosphoric acid ; and when acted en by ignised hydrate of
potash, it emitted a smell of ammoifia, and appeared ta disadvt
m the alfcalir which yielded maria«ic acid whem dM eulphorse
added to it* '
0» OxgmwSett^fi Aa^ ttp
Ko iobstaiife known ta contaio oxygen eovM be ^AtalMdliy
causing ammonia to act upon the phosphiiretted licfuor of 0«f«
Lussae and Thenard, or oq the sulphurelttd muriatic liquor «C
Thomson.
When 15 or l6 parts of oxy muriatic acid are mixed with 40^
tO'4d parts of ammoniacal gas, from 5 to $ parts of hilrog<^ are
produced, and the residuum is dry muriate of ammcmia ; no water
h formed^ ^ *
Equal bulks of oxymuriatic acid gas and hydrogen mixed O^o^r
water, and fired by the electric spark, always deposited a sl^fat
Tapour, and were condensed from l-lQIbto l»20th of their b«lk^
the remaining gas was muriatic acid. When sulphuretted hy^
drogen and oxy muriatic acid gas after being both dried wtnr
mixed Wi equal volumes, the condensation was not l-40th, eoltt
phur appearing to retain a litde oxy muriatic acid was deposited'
iNit no vapour, about 19-20ths of the reeidual gas was moria:^
acid and the reaiainder was inflammable.
Hie idea of water existing in muriatk acid is bjrpo^itea! de*
{lending upon the assumption of oxygen existing in oxymurialic
gas* Gay Lussae apd Thenard's experiment, in which miirtttte
acid gas was passed over litharge, and one-fourth of water wai^
obtftiued, may be explained by supposing the ne^ compound to Ims-
similar to th^t formed by the oxy muriatic acid and lead, to fbrar
which the muriatic acid must lose its hydrogen and the litharg|il
il8 oxygen, whence the water would be formed.
When quicksilver acts upon muriatic acid gas by electrieitf,
calomel is formed, and about half its bulk of hydrogen it evolv«!i&
Wi^h potassium over very dry quicksilver, the hydrogen is ironr
9 to 1 l-2(Hhs of the muriatic acid, and in the diecomposition of
aiufiatic acid gas by tin and zinc about half its bulk of liydrog^i
was disengaged, and salts similar to those produced by tin and'
aiuc on being burned in oxymuriatic acid gas were produced.
Scheele's view of the muriatic and oxymuriatic acids, althot^bi
obscured by his language, is therefore the real expression of tM
facts, and the French theory merely hypothetical. Oxymurt»r
tic acid combining with hydrogen to form the common murifttte ^
acid. When muriatic acid is treated with, metals, the hydrogen
it separated by the superior attraction of the metal to theoxy*
muriatic acid^ and the resulting compound which has been coo«
sidered as a dry muriate is in fact a combhtation of oxymuriatier
acid with an infltmimable base. On adding water to Libavins^i'
liquor, it is decomposed, its oxygen unites with the tm and ite hf*-*
dicogen with the oxymuriatic acid so as to form muriatic aoid-«
The combinations of oxymuriatic acid with inflammable baser
are not decomposed by dry acids, and this seems to. distinguisic
them from the muriates, with which they have been confouadedtfi
Thus muriate of potash, according to Berth^llet's analjais,:
4S!S On OjBgmUriaik AeH^
tp be a CiOmbmati^ii of oxynaunatic acid with poUfsidm, while
«al atnuoniac is muriate of atnmoniat from which when dec'cm*,
posed by potassium the ammunia and hydrogen are evolved at the
same time that the oxymuriatic acid combines with the potassium
«Dd forms a muriate of potash.
. (The heat and light emitted by bodies in oxy muriatic acid ga»
does not arise from contained oxygen, but are merely owing to
the intense agency of combination^ in the same manner as hap-
pens to sulphur and metals, or the alkaline earths and acid^. The
analogy between the compounds of oxymuriatie acid with the.
metals, ^nd th«^ common neutral salts- is very distinct ; and aS;^
there is only one known combination of hydrogen with oxymu-
liatic acid, so the quantity of hydrogen evolved during the decom-
position of muriatic acid by metals is always the same ; jLlie at*
traction of oxymuriatie acid for hydrogea seems to be weaker
than with any other inflammable body.
Oxymuriatie acid gas was not altered bv electric explosions,
from platina points^ continu?d for several hours; neither was
any gas separated by a Voltaic battery of 1,000 double plates^e
ixom the oxymuriates of phosphorus or of sulphur, unless a mi.,
nute quantity of water was present, which being decomposed,,
yielded hydrogen. This gas is also emitted from the liquor of
libavius in a similar case*
As to Chenevi.Vs hyperoxymuriatic acid, the tiyperoxy mu-
riate of potash distilled with dry boracicacid yielded principally
oxygen, with a little oxymuriatie acid, and muriate of potash.
The orange coloured fluid produced by dissolving hypero^ymu-,
xiate of potash in sulphuric acid affords much oxygen with oxy-
muriatie acid. When solutions of muriates, or muriatic acid are
electrized, oxymuriatie acid is evolved at the positive surface,
and hydrogen at the negative. When a solution of oxymuriatie
acid is electrized, oxymuriatie acid and oxygen appear at the
pofiitiYe surface, and hydrogen at the negative. These facts are
unfavourable to the idea of the existence of iiyperoxy muriatic,
acid. The principal products arise from the decomposition of
water, as happens when dilute nitric or sulphuric acid is elec*
trized.
The byperoxymuriate of potash seems to.be a triple com-
pound of oxymuiiatic acid, potassium and exygeu ", the latter
being probably combined with the potassium, which appears
lyipable o^ uniting with more oxygen than exists in potash, while
oxymuria^^*^ *^^^ has no affinity for oxygen. If hyperoxynau-
liate of P^^^^^ ^^ decomposed by nitric or sulphuric acid, it.
yields oxv"^^^^^^^^ ^^^^ ^^^ ^^yfS^^y if decomposed by muriatic
acid it vie^^* oxymuriatie acid only, which unites with the same
qnantity o^ hydrogen as commoa oxymuriatie acid gas (torn
maoganese.
On O^iafmiriafic^ciitL 43$
The gds emitted during the solution of i>)atiQa is not hyper*
Qxymuriatic acid, Uut oxymuriatic with nitrous vapour diffused
. through it; froin\vhich it may be freed by washing. The same
,gas is formed during the production of aqua regia by the hydro*
gen of the muriatic acid attracting oxygen from the nitric acid;
but this gas is not produced when platina is dissolved in per.
fectly formed. aqua regia.
In reality, oxymuriatic acid has not yat been decompounded,
and it appears to be a peculiar acidifying principle belonging to
the same class- of bodies as oxygen, forming compounds witl^
inflammable bodies analogous to acids or oxides, but differing
in being for the most part decomposable by water. So that
muriatic acid has hydrogen for its base, which is acidified by^^
oxymuriatic acid; the phophoric sublimate is phosphorus aci-
dised in the same manner; and Libavius's liquor, as also arsenic
treated with oxymuriatic acid, are analogous compounds. The
combinations of oxymuriatic acid with lead, silver, quicksilver,
potassium, and soda, incline to the nature of oxides.
Oxymuriatic acid seems to form three combinations with
phosphorus. The pbosphuretted muriatic acid of Thomson con-
tains the maximum of phosphorus. The sublimate from bpraciuat
. may be considered as boracium acidified by oxymuriatic acid.
Whenever an oxymuriatic combination is decomposed by wa*
.ter, the oxide, acid, alkali, or oxidated body formed must be, in the
same proportion as the muriatic acid gas, as the oxygen and hy-
drogen must be in the same proportion to each other :'so that ex-
periments on these compounds afford simple means to ascertado the
proportion of the elements in oxides, acids, and alkaline earths.
If hydrogen be considered as unity in weight, then oxygen will
be nearly 7*5. If potash be composed of an equal proportion of
its ingredients, then potassium will be 40*5, and potash, suppOB«
ing it to contain 1 5*6 per cent, of oxygen 4$. From the com-
bustion of potassium in muriatic acid, oxymuriatic acid is 32*9,
and muriatic acki 33.9 ; which agrees with their specific gra-
vity. One hundred cubic inches of oxymuriatic acid gas at .a
mean temperature and pressure weigh 74'd grains ; by the above
. calculation, they should weigh 74*26. Muriatic acid gas 39 gr,
instead of 38.4.
As during the decomposition of the amalgam from ammonia,
one in bulk of hydrogeu and two of ammonia are disengaged, there
. is a striking coincidence as to definite pvoportions, let which ever
theory of this compound be adopted.
It was, once thought that metallisation might be explained by
, adopting a modified phlogistic, theory, and supposing three kindg
ol metals, 1° ammonium, iu which hydrogen is so loosely corn-*
bined, as to be very easily, separable, 2^ the metals oi' the alkalies
and alkaline earths, the hydrogen of which forms in comb^si^pn,
VOL. YI, — NO, 26. 3 K
430 On Oxytnuriatk Add.
water separable from the base, 3^, the common metals and thoflf
of the earths, the hydrogen of which in combustion produces
water nof separable by any new attracrions. But the action of
potassium and sodium upon muriatic acid seems to overturn thetc
speculations as to the alkaline metals.
The oxy muriates being considered as compounds of oxymuria-
tic acid and inflammable bodies, strengthens the opinion that
potassium does not form a hydrate of potash by combustion, for
the quantity of oxyrauriatic acid required to form a muriate,
' sho\ys that it is the simplest known form of the alkaline matter :
this seemif to be an experiment um crucis. The potash formed by
combustion of potassium is a pure metallic oxide, and requires 19
per cent of water to convert it into a hydrate similar to potasfh
prepared by alkohol, and then heated to redness.
Charcoal does not combine directly with oxymuriatic acid,
but this union may take -place by the intermedium of hydrogen :
the oily substance from oxymuriatic acid gas and oleliant gas,
seems a compound of this kind, as this oil treated with potassiumi
forms muriate of potash, and some kind of gas. Aiti^cial cam-
phor and muriatic ether are of a similar nature.
The decompositions of the muriates of potash and soda may
be better explained by these new ideas than before. When ala-
ininous and silicious substances decompose common salt by the
intermedium of water, the sodium may combijie with its oxygen
and the earth to form a vitreous composition, and the oxymuriatic
Ucid with its hydrogen to form muriatic acid. In decomposing
common salt by moistened litharge, the oxymuriatic acid is
attracted by the lead, and the sodium combines with the oxygen
of the litharge, and with water,' to form hydrate of soda, which
gradually attracts carbonic acid from^ the air. Steam being
passed over a mixture of iron filings and muriate oi soda intensely
belated, hydrogen was emitted, little h^'drate of soda was formed,
and muriate of iron was produced. It is not improbable that by
u skilful combination of complex affinities even potassium and
sodium may be procured in their metallic form from their oxy-
muriatic combinations. •
• As the compound c>f oxymnriatic acid, phosphorus and am-
monia, resembles silex, or the oxide of columbitim in its geneial
chemical characters^ is as refractory to common reagents, aad
Us nature to be detected only by the effects of combustion, or by
the agehcy of fused potash, it is likely that liiany substances
now supposed to be elementary may be reduced to simpler forms,
iEind aii intense attraction in equilibrium may give to a compound
body of several ingredients, the refractory character generaUy
attributed to the homogeneous natore of its parts.
As oxygen is not an acid but forms acids by combinnig
with iafiammable bodies, so oxymuriatic acid by luiitiog
On Oxt/muridHc Add. 431
wl^h'simiiar substances, may form either acids, as is the case
with hydrogen, or compounds like acids or oxides capable of
forming neutral combinations as in the oxymuriates of phos-
phorus and tin. Oxymuriatic acid in respect to electrical pow-
ers may i)e supposed to be negative iii a high degree, and in most
of its compounds except those containing the alkaline metals
Which may be conceived in the highest degree positive, arid the
metals With which it forms insoluble compounds, it seems still
to retain its negative character.
It remains to correct or extend the former inquif ieS' respecting
sulphur and phosphorus.
. Crystallized native, sulphur was sublimed in nitrogen, and
litmus paper placed in the upper part of the retort was slightly
reddened, so that it was not absolutely free from acid matter.
If the retort is not lined with sulphur, when that siibstance is
acted upon by potassium, som^ of the latter acts upon the gas,
and when too much sulphur is used, the sulphuret of potassium
is not entirely decomposed by an acid. Sulphuretted hydrogen
being soluble in muriatic acid, its quantity is liable to he under-
rated. And when large quantities of sulphuretted hydrogen are
treated with pi>tassium, the intensity of the combustion occasi-
ons the decomposition of much of the gas. To avoid these
errors muriatic acid satur^ited with sulphurett'^d hydrogen ov«r
mercury, sulphur distilled from iron pyrites in vacuo, and which
did affect litmus paper were employed, and the sulphur conibined
in glass retorts lined with sulphur and filled with nitrbgen or
hydrogen.
One grain of potassium, yielding when treated with water,
about 1 cub. inch and 1^1 6th ofhydrogen,was acted upon* by half a
^rain of sulphur, some of the latter sublime, heat and lighl were
produced, and from 1-1 4th to 1-1 0th cub. inch, of sulphuretted
hydrogen evolved. The compound treated with muriatic acid
saturated with sulphuretted hydrogen, yielded from 9-lOlhs to
11-lOths cub. inch of that gas. When the proportion of sulphur
is increased to twice or ten times the weight of the potassium,
from 7-lOths to 9-lOths cub. inch, of sulphuretted hydrogen .is
evolved, by the action of the acid; but if the buperfluous sulphur
is dri\/.n oft' by heat, nearly the former quantity of gas can be
collected : so thai sulphur seems to combine always with nearly
three times its weight of potassium, and this proportion is such
that the compound burns into neutral sulphate of potash.
When I gr. of potassium acts upon I'l cub. inch, of sulphu-
retted hydrogen, the hydrogen is set free, and sulphuret of potas-
sium, contaming as usual one-fourth of sulphur is forthed. ' A
large quantity of sulphuretted hydrogen being employed, some of
at is absorbed, an eqyal bulk of hydrogen is disengaged, a com-
pound of sulphuretted hydrogen and sulphuret of potassium is
3 k -
432 On Csymuriatic Add,
formed, which yields by an acid Dearly twice a« much' sulphu-
retted hydrogen, as sulphuret of potassium.
Potassium and phuspborus combine in only one proportion*,
1 gr of potassium taking up 3-8th gr. of phosphorus, and the
phosphuret yielding with muriatic acid from S.lOths to 10-lOthi
cub. inch of phosphuretted hydrogen. Half a gram of potassium
decomposes, nearly 3 cub. inch of phosphuretted hydrogen, and
•etsfree more than 4 cub. inch, of hydrogen.
According to Dalton's idea of pr6portions, the number repre-
senting sulphur, if taken from its union^ with potassium, would
be 13'5. The specific gravity of sulphuretted hydrogen at a
mean temperature and pressure is 10645, that of sulphureous
acid gas, 209^7* Sulphuretted hydrogen contains an equal bulk
of hydrogen, hence the number representing sulphur is 13 4.
Sulphur burned in oxygen always produces some sulphuric acid,
and from 92 to 98 parts of sulphurous acid from 100 of oxygen
in bu'k, whence sulphurous acid seems to consist of sulphur
dissolved in an equal bulk of oxygen, to that supposing the acid
gas to cont'^in one portion" of sulphur and two of hydrogen, the
number representing sulphur would be nearly 1S'7> but this esti-
mate must not be considered so accurate as that from sulphuretted
hydrogen.
Twenty five parts of phospjiorus absorb in combustibn about
34 in weight of hydrogen, so that considering phosphoric acid
composed of 3 oxygen anJ 1 phosphorus, the number represent-
ing phosphorus will be about l6'5, not very remote from that
which may be deduced from the composition of phosphuret of
pota'^sium.
These numbers do not exclude the existence of combined por-
tions oi oxygen and hydrogen in sulphur and phosphorus, but it
is not unlikely that these gases are not necessary tc) their exis-
tence. Perhaps in all cases phosphorus and sulphur contain
small quantities of the hydrurets of those bodies, and the produc-
tion of sulphuric acid in the slow combustion of sulphur is pro-
bably connected with the production of water: and further, per-
haps the pure oxides of sulphur and phosphorus may exist in
common sulphur and phosphorus, and with hydrogen be the
cause of their various appearance.
The red colour of common phosphorus seems owing to a slight
mixture of oxide. Common roll sulphur is very pale yellow ; the
Sicilian sulphur is orange, and contains oxygen, so that it pro-
bably contains oxide of sulphur. The sulphur distilled from iron
pyrites in vacuo is pale yellowish green. Part of the sulphur
from pyrites is usually soft and emits the smell of sulphuretted
hydrogen.
Sulphur sublimed in oxymuri'atic acid gas absorbed part of it
and formed a tawney orange liquid, which s^eems to consist of
\
OttO^^urioHe Aad» 4Sf^
1 sulphur, represented by 13*5| aad 1 oxymurmiic acid repre«
seiTted by 32.9.
Three g'rains of pliospfaorus were converted into a sublimate.'
daring combustion, by the absorption of about 23 and an half cub.
inch; oxymuriatic acid gas, without any evolution of oxygen, or
formation of muriatic acid. The sublimate seemed to have con-
tained 1 phosphorus represented by l6*5 and 3 oxymuriatic acid
represented by 9S 7*
O&scrvatians.'^A late writer has remarked [Edinb. Monthly
Mag.] that although the specific gravity of muriatic and oxymu-
riatic acid gases agrees with Mr, Davy's theory, yet that he does
not seem to be aware of the difference between common oxymu-
riatic acid and that produced by Cruikshanks from muriatic acid
and hyperoxy muriate of potash : but when four parts of water
saturated with common oxymuriatic acid, are mixed with one
of liquid ammonia, a considerable quantity of nitrogen is disen-
gaged, whereas Cruikshank's acid either disengages no nitrogen
or at least very little.
When hyperoxymuriate of potash is healed, it yields one third
of its weight of oxygen which is not likely to come from the pot-
ash, as oxygen adheres so strongly to potassium, and it is still
jess likely that water should be decomposed.
There is no reason that common salt should be considered as
an oxymuriate of sodium in its metallic state, for other acids
unite with the bases and why shpuld not the muriatic ? It is
probable howevei*, that the liquor of Libavius, and those sub-
stances called butters, agree with Davy's theory, but when
water is used^ the compounds are really muriates.
9bfm
Observations on the researches of Messrs. Gay.Lussac and The.
. KA&D, reiative to the Jlmalgatn tf Ammonia* By Mr, Davt*
Journ, de Physique. May I SIO.
Gay»Lussac, and Thenard observe, that the first researches on
this subject were made by Dr. Seebech, in the beginning of
1S08; now Berzelius and Pontin bad communicated their experi-
ments to Mr. D.in the middle q( that year ; of course it cannot
at present be said who was the discoverer. '
Gay-Lus?ac and Thenard aflSrm, that Davy considers ammo-
nia as a hydrogcnised metallic oxide, but although it was said,
that ammonia might have a base which produced the volatile al-
kali by oxidizement, yet it was positively stated that tfie phe-
nomenon might be explained by supposiiig ammonia was metaU
lized by conibining with hydrogen.
434 On the-AmalgM of
Gay Lassac and Tbenard 8up[>ose the amalgam la consist o f
ammonia, quicksilver and hydrbgen, as it yields those substances
0ta being heated \ but it is impossible to ir^ an amalgam as soft
as butter from water by wiping it with blotting paper, or merely
cutting away its external part. And again they obtained %0 parts
of ammoniacal gas, and 23 of hydrogen, whereas the dry amalgam
always yielded nearly 2 parts of ammonia, and one of hydrogen.
And the ammonia in their experiment must have been absorbed in
the water attached to the amalgam.
Gay-Lussac and Thenard, estimate the ammonia and hydro-
gen in the amalgam at 0*0007 of the weight, and imagine Davy
was deceived in supposing the quicksilver contained only 1-i 2000th
of foreign matter, by attempting to weigh the increase by a
balance. But this statement was a minimum deduced from an
experiment in which the amalgam yielded one and one half of its
bulk of ammonia. Since that, another experiment has been des-
cribed, in which. the amalgam contained according to Gay-Lussac
and Tbenard, l-900th of ammonia, or according to the other the-
ory, l.l6O0th.
They observe, that although the weight is but slightly in-
creased, yet the formation of the amalgam may be explained by
considering that the two gases are retained in it by very feeble
affinities, and, of course, scarcely condensed ; so that they do not
consider the great expansion of quicksilver, and its solidifica-
tion by a substance, which according to them, is in an almost
gaseous state.
If Gay-Lussac, and Thenard, only wipe the amalgams
formed by the metals of the earths with blotting paper after they
have just been taken out ol the water, they will easily conceive
these bodies to be merely hydrogurets. They suppose amalgam
of ammonia to be a mixture of quicksilver, hydrogen, and am-
monia, because it yields hydrogen when treated with oxy muriatic
acid, but this fact is still more favourable to the contrary suppo.
sition; for if the hydrogen came from the quicksilver, it would b«
in a nascent state, and would decompose the oxymuriatic acid,
whereas, if it comes from, the interposed waterit would be ela^ic
before it reaches the surface, and this is the case, for the globules
are manifestly emitted from the internal part of the mass.
No positive decision can be niade on this subject ; the difHcuL
ties in each of the theories have already been shewn, and nothing
positive has-been advanced. On one supposition, nitrogen com-
bining with l*4th its weight of hydrogen forms an alkaliy and the
addition of -I -12th more hydrogen produces a metal ; xm the other
idea, although nitrogen cannot decompose water, yet a mixture
of hydrogen and nitrogen can produce that ellVcl. And again it
has been said that the metal from ammonia may be regarded as a
simple body, and hydrogen and nitrogen as oxides of it. The true
theory of these substances is io fact not known^ ^d the exper
On the Amalgam of A^nmwna. ^ 4d5
men is of Gay-Lussac and Thenard have not added mneh to our
kno\vledge of these substances. They attribute the sreit ejBPervei*
cence at the negative pole ^hen a solution of ammonia is used
"Without quicksilver, and the slight effervescence when quicksilver
is added, as a proof that the gaseous substance combines with tbe "
quicksilver ; but if a solution of silver be added to tbe ammonia,
the effervescence ceases, and the silver is revivted ; so«th^t accord*
ing to rheir ideas, the gaseous substance must have combined
with silver. Indeed, although their opinion is the most prubabkt
it does, nevertheless, accord the least with the general analogy of
chemistry.
Answer^ by Messrs, Gat/'Lassac and Thenard, — ibid*
' Mr. Davy affirms that he did not state ammonia to be a hydr«*
guretted metallic oxide ; but that he only, stated the facts and pro«
posed certain questions. Now Gay-Lussac and Thenard, only
spoke of this composition of ahimonia, as being a necessary, con*
sequence of Davy considering the ammoniacal amalgam as a com*
position of quicksilver, and a met^l, which possessed the property
of becoming ammonia by decomposing water ; while at the same
time he then believed that azote was composed of hydrogen and
oxygen,. and d?ffered from water in the proportion only of its in-
gredients. It is only necessary to examine the original essay of
Davy in the Bibliotheque Britaunique, No. 324, for June, I8O9,
pages 124, 137» in order to be satisfied that he has always con-
ceived the amnioniacal amalgam to be composed of quicksilver,
Itnd a peculiar metal which he has even proposed to call 'ammo*
niom.
As to Mr. D's final observations it may be remarked, that the
most probable conclusions are those which accord the most with
the general analogy of chemistry ; and G*L. and T. cannot biit^
imagine that they have added very considerably to the knowledge
of the ammoniacal amalgam, especially as fhey have even exposed
some of th^ errors of Mr. D. himself, who says (Bibl. Brit. No. 324,
p.l34), that it decomposes air and sulphuric acid, and by expo8ur<S,to
the atmosphere it becomes covered with a layer of carbonate of am.
monia, whereas it has no action upon either air or sulphuric acid,
sind cannot-possibly be covered with tbe white powder of car bo*
nate of a^inmonia by exposure to the atmosphere. However
imperfect the experiments of Messrs. G-L. and T. may be, they
seem nevertheless to have made Mr. D. change his opinion, as he
now esteems their exposition tbe most pi>obable.
It is still probable that the ammoniacal amalgam is composed
of quicksilver, ammonia and hydrogen, for Mr. D. only opposes the
impossibility 6f drying the amalgam by blotting paper, wbich is
certainly very difficult, but it was only the internal part that was
taken, from an amalgam artificially cooled^ in order to augoKint
4A6 On the Mctak from tAe Jfkcjiu.
tbe conswUnce thereof. In order, however, to get ridoftercty'
possible objection, a liquid amalgam of potassium was made, aad
placed 'iu a saucer of moistened sal ammeniac, and thus by Ai < D's
• process a very bulky combinatk>n of potassium and ami.;otii<t,Cwui a-
snalgam was obtained. The upperpavt of this mass was i.'.ken oti l^y
a knife, and the internal part was separated by a veiy dry iron
spoon, put into a tube almost full of quicksilver, which had lately
been boiled in it ; and after being closed w.th a very dry stopj^er,
the tube was reversed in quicksilver. The decomposition ot ;he
amalgam was aided by agitation, and a mixture of about 2.6. of
ammoniacal gas with 1 of hydrog«n was emitted in some quan-
tity. Now neither the quicksilver nor the vessels were moist,
for on putting some amalgam of potassiuni only into them, no
gas was tniitted ; nor can it be said that the amalgam itself con-
tuned any water, lor that fluid cannot exist along with potassiuoi*
Now as it was very easy to separate the external pait of the amal-
gam, this experiment is perfectly convincing; and it is evident
that the potassium, being combined with a very large proportiun
,of quicksilver, cannot art sit^icienily upon the ammonia and hy-
drogen so to cause them to combine together, so that the ammp*
niacal amalgam of potassium is subject to the ^ame laws as that
fornoed only of quicksilver, ammoiiia and hydrogen, aud whiqh
can only exist by means of the electric agency.
If Mr.D. con&ide,rb theammoniacal amalgam as composed only of
4|aicksilver, ammoniumi and hydrogen, he must either admit this
axplaiiation of its formation, or assign a reason for its being five
or six times as bulky as the original quicksilver. But as the
hydrogen and ammonia are scarcely more condensed than when
in a gaseous state, as is evident from the facility with which they
%re disengaged, it is no wonder that they diminish so considerably
the specidc gravity of the quicksilver.
s=sc
jfn tTamination of some Observatiom of Me$irs. Gat.Lussac wd
THxiviHD, on the facts relative to the Metals from the AlkeHa.
By Mr, H. Davy.— /ottm. de Pht/s, May^ 1810.
Gay-Lussac andTiiENAUD say, that it is very easy to exbi-
*hit the absorption of hydrogen by potassium, and that it is pro.
bable that Mr. D. employed too high a temperature. In theMo-
tiiteur, for 1808, it was announced that the absorption took
place at a very high temperature ; in the Metal. d^Arcveil, voL.2'.
that the heat should be rather under a cherry red; but in their
last report they say, that all the hydrogen was got rid of. by a
less heat.
Mr. D. has never said that he exposed potassium to hydrogen At
a>l temperatures $ potassium was. heated in a. plate. glasi3 retort un-^
0/t tie Mettiifrom the ^/BJaSeu '4V$
tU it began to soblimt and potassuretted * hydr«gen waa formed,.
yet the potassium was not changed into the gray powder, nmr
eten when the operation was performed according to their state*
ment, did the absorption of gas equal one tenth the bulk of th«
metal.
G.-L. and T. have not attended to the solution of potassinm ia
hydrogen^ in which a condensation probably takes place ; oor to
the action of the metaV upon glass ; nor to the observation that
when either air or water is present in a minute quantity, a greyish
powder is produced. Hydroguret of potassium was not obtained
even when the hydrogen was carefully dried ; hence it is probable
they did not employ thi same method.
It is not true Uiat Mr. D. has ever positively asserted nitrogen \m
be composed of oxygen and hydrogen : it was only said ihat if
tlie results of the distillation of the fiisible substance in iron tubes
be rightly stated, tlie nitrogen appears to have been decompose^
in the operation, and oxygen appears to be one of its elemento |
but this was a mere doubt.
It is not true that Mr. D. has ever asserted that on burning the fn*
sible substance in oxygen, a small loss «f nitrogen takes place; but
the direct contrary. It was on burning the phosphoric substance^
refraining in the distillation of the fusible substance, by a re^
heat and preserved under naphtha, that a small bss of nttrogui
was observed,
Messrs. G.-L. and T. say that potassium absorbs the same quan*
tity of ammonia whether the gas be dried by means of potash, or
in its ordinary state : but when ammonia ir not perfectly dry. an
cfiervescence takes place, and the metal is covered with a cmat of
potash, so that less ammonia is consumed.
There is a total difference in the results of the distillation of
the fusible substance, to which G-L. and 1\ have not adverted in
the least. Their statement is true, only in the case that water
is present, as they say tha% it yields 2-5ths of ammonia and l*5lh
of hydrogen and nitrogen in the proportion of three to one« as they
exist in ammonia. Bnt if the fusible substance is prepared with
great care to avoid the presence of water, 6 grains of potassium
absorb (in round numbers) ] 2 cub. in. of anmionia, and leava
6 cub. in. of hydrogen; and when the potassium is revived, ab^ut
6* cub. in. of hydrogen, and as libuch of nitrogen, are emitted
with very little amnionia.
. Theprincipal reason for supposing that ni trogen was composed of
hydrogen and oxygen, was a reliance upon the statement of Messrs.
>G-L. and T. but on distilling the residuum much lejn nitrogen waa
discovered^ The use of iron tubes afforded results that seemed
tl> shew that part of the ammonia Was not destroyed, and that
the nitrogen was decomposed; but there are several objectiont to
the use of these tubes, and the apparent chaa|^ of soon potttWiilVI
Na. 26.— VOL. Yi. ' 9 h •
4$|. On (he Metubfroffi thi Alkalies.
iota potash in the former experiments probably depends upon its
con^bining with the tube at a white heat, .
The nature of nitrogen is still doubtful : several facts, ihdeed,
•rem to shew that ammonia contains the same elements as watey,
but it can as yet be neither positively affirmed or denied.
: Messrs. G-L« and T. say, that when the fusible substance is
beated- with certain metals, ammonia and nitrogen are produced,
and the residuums effervesce with water ; hence the residuums are
probably alloys of potassium, and as nitrogen is emitted, it is the
ammonia and not the potassium that is decomposed. It is very
easy to explain th^ phenomena of the combustion of the alkaUne
and other metals, by supposing them to be composed of hydro-
gen united with peculiar bases, but then the alkalies and other
metallic oxides must be considered as compounds of the same
bases along with water : and if this hypothesis be followed, there
are no means of knowing what are the qualities of these bases
when uncombined. In this point of view it is improper to say
that potassium and Soda ar« compounds of potash and soda with
hydrogen.
jfnmer 6t/ Messrs* GaymLussac and Thcrmard.
. Mr. Davy says he has not been able to combine hydrogen with
potassium so as to form a sulid hydroguret ; but if potassium is
beated in a bent tube filled with hydrogen, standing in mercury,
a quantity of hydrogen equal to l*4th of what would be expelled
, from the potassium by water will be absorbed. This experimeut
has been repeated several times, so tljat it is certain that a solid
hydroguret of' potassium can be formed, the properties of which
are related in the Bibl. Brit, for Sept. I809, p. 47.
As to nitrogen being affirmed by Mr. D. to be composed of oxy.
gen and hydrogen, it is only necessary to pioduce, first, a note
written by Mr. Davy, SO June, 1808, and sent to the editors of the
Bibl. Brit* along with his paper, in wluch he says, *^ Since this
has been, written, I have examined the rc^ciprocal action of potas-
sium and ammonia under a great variety of circumstances.
When the^experiment is made in contact with platina, and mois-
ture is carefully excluded, scarcely any ammonia is reproduced,
and on pushing the distillation to a \vbite heat, there is not ob.
tained more than half of the nitrogen and hydrogen that ought
to compose it. Therefore in this experiment there occurs a loss
of nitrogen, and instead of it, there is to be found only the oxy-
gen that is united with the potash, and a little hydrogen. Numc
rous experiments which have occupied my time about four montbf,
and in which only white glass retorts, and tubes of polished iron
have been used have led to i\n^ formidable conclusion, which I re«
sisted as long as I could, viz. that ammonia and water f.re com*
jK)8td af the same ponderable substance or base, and that tktir
On the Metals frm the Alkdiei. ^ 419
peculiar forms, and those of the gases that are extracted from
them, that is to say, oxygen, hydrogen, nitrogen, and the ni-
trous compounds depend upon electric powers, that is to say, on
Imponderable agents/' Another note has also been published in
the Bibl. Brit. May, 1809, in which Mr. Davy says, " I com-
municated last night to the Royal Society, the details of a series'
of experiments which have led me, as it were by force, to a' con-
clusion that would otherwise have been conceived to be improba-
ble, namely, thai ammonia and water have for their base ifie
sanrie ponderable substance/' These notes are perfectly justifica-
tory as to the assert-:on complained of by Mr. D. '
It was needless for Mr. D. to complain of the mistake m*ade
in saying that he found a loss of nitrogen on burning the aniiho-
jiinret of potassium in oxygen, for it was rectifyed hs soon &s
made, in a note by Mr, Picket, on publishing the paper in tlje
Bibl. Brit. No. 33Q.
Mr. Davy says (Bibl, Brit. No. 330, p. 31,) that potassium ab-
sorbs more ammoniacal gas dried by lime than the common la
the proportion of \6 to 12. 5. but in reality the absorption if
equal when the temperature is equal. What he calls potash, is
really an ammoniuret. * *
The difference between the products obtained by exposing the
ammoniuret to heat does not depend upon the presence of waffer
as is supposed by Mr. D. but on the high temperature to whl^h
be exposes itl ) .
The above notes shew that it was not upon the ground of otir
assertions that he believied, at one time, nitrogen to be composed
of oxygen and hydrogen ; but upon his own experiments durirfg
four months which led him to Xhh formidahte conclusion, as He
calls it. At present he does not suppose nitrogen to be comfVosed
of oxygen and hydrogen. •*
Potassium emits the same quantity of hydrogen when treated
Vith ammonia as with water ; and when the ammoniuret is atier-
'wards dissolved in water, no gas is emitted. Mr. D. has sustained
a contrary opinion, but his objections have been answered li* the
Bibl. Brit. No. 330, and as he has not replied, it is to be sap-
posed that he is now convinced of his error.
Oi»*en7fl/iw#.-r-In the Supplementary Number, pu
jiionth, will.be given the third controversial paper of i,\v, Pav^
|M)4 the reply of tl^e Fremrb cheaiisti • '
(<«»)
On Potash and Soda prepared by means of Alkohol. By Mr. TfAfLm
C£T. jfnnaUsde CkimtefVol. 6S.
In order to discover in the most easy manueF^lie quantity ^f
, pure alkali, in the different kinds of potash and Of soda, the me-
. tbod of Descroizilles, with sulphuric apid,(see.Ke.trospect, vol. iii.)^
.was preferred, and the following course of eKperiments were un-
dertaken, in each of which nol less than 2f) grammes (2-3ds 6f^
« im ounce) were employed, and almost always 100 gr. (3 oz.) and
. the mean result of four experiments of the same kind was coa«
. f tantly taken.
The subcarbonate of soda was prepared by succesive crystal-
lisations in which the small quantity of muriate and sulphate of
. aoda that it contained was separated, it was then reduced to pow-
der aud dried by a heat of 12 to 14° cent, therm. (53 to 57 Fabr.).
The sulphuric acid employed was of the specific gravity of 1*854^,
and was reduced tu l*oiS6 by being diluted with 9 parts of distilled
m'atef.
The subcarbonate of soda analysed with the greatest care, was
composed of 63. 6l. per cent, of water, 1^*04 of carbonic a^,
•and ^0' 35 of soda.
One hundred grammes (3 oz.) of this subcarbonate, was satu^
• vatvd with the diluted acid, and on the mean of several experi-
ments it required 347 gr. that is to say, 34*7 grain of the strong
acid ; so that whenever this qiiantity of sulpjburic acid of that
atreugth was employed to saturate a parcel of soda, it{represented
100 gr. of subcarbonate in the abovementioned dtate, or 36*39 Q^
anhydrous subcarbonate, or 20'35 of pure soda.
1a lieu of this subcarbonate, caustic soda prepared with alko.
. liol wiiich is held to be the true type of this alkali, was used;
but tha results entirely contradicted this opinion. Four speci.
mens which had been melted in a silver saucer being examined,
all of them contained some traces of muriatic acid, and a propor-
tion of carbonic acid as was easily discovered by barytio salts,
barytes water, lime water, &c. but too slight to occasion any
affervesence with acids. Twanty gi^ins of each of these speci*
mens absorbed respectively 110-2 — ll6*75— llL-5 — 112-2 gr.
of concentrated sulphuric acid: so that the mean is 112-66S gr.
The same experiments were repeated with several specimens of
puie soda, which had been melted in a silver crucible, and kept
for 20 minutes in a red heat, but the results scarcely differed from
the preceding.
It appears that when subcarbonate of soda is used, it requires
170*515 gr. of coDcentratet^ sulphuric acid to saturate 100 gr. of
J
Q»Po$asl and Soda preparti b^ ^deam of AUcokoL 461
. code, but 112*662 gr, of the same acid are sufficient for 100 gr.
of soda prepared with alkohol, so that either that soda is not ptu*
. or the analysis of the sobcarbonate is wrong.
In order to remove these doubts, 1000 gr. of perfectly purs
crystallised sulphate of soda was decomposed by barytes, a slight
excess of it baiiig added, th^ soiuiion was carefully evaporatedf
and one half the residual soda was treated with soda aod the other
/half was dissolved in barytes water, then evaporated hastily, aod
melted as well as the other moiety in a silver crucible by a red
beat. One hundred gr. of that prepared with alkohol absorbed
1 1<)*6 gr. of concentrated sulphuric acid, and that prepared with
i)aryfces water absorbed 12i'4 gr« of the acid, to that soda pre^
pared wilb alkohol appears to contaii) only 71 or 7^ per cent, of
such alkali as that found ia the, subcarbonate or sulphate of
soda«
Similar experiments being made upon potash prepared with aU
kohol, and the salts having potash for their baa^s,* it was found
that the former contained 6nly 73 or 73 per cent of its weight of
real alkali. Of course tMs supposed pure ^kali cannot be used
to determine the proportion of the ingredients in salts, and many
experiments and analyses which have been iouiidad upon the purity
of this alkali ntust be carefully reviewed and their results altered.
.In particular Vauquelin has used the quantity of nitric acid of
a given density that is requisite for the saturation of a cartain
<|uantity of potash purified with alkohol, as a standard for cooi-
(aring tJbe quantity of alkali that is coutained in the difiieraiit
inds of common alkali, which may occasion great errors in vain*
ing the proportion of alkali contained .in different neutral salts. \
Berthollet on examining the methods of Richter, andXirwao,
fo<md that the latter had not only been obliged to make a great
mmiber «f evaiaatimis, but had also pfoeeeded upon • ^itty uA.'
certain principle, to which last much of the incertitude of bis
'Msd'ts is to b« attributed. Nevertheless as Kirtvan employed^ tha
subcarbonates ef potash and soda to determine the quantity of al«
kali that the neutral salts contained,' he had only the inevitable
CTfors incident to all experiments to combat, and if the quantity
of tha acids bad been determined upon more certain pnnciples,
ills rtstilts would have approached raore near to the truth.
Bertboilet followed a direct method, but his nesults would have
been more certain, if tbe quantity of water retained by muriatic acid
had been fixed, and if he had adopted Kirwati's use of the sub-
«art)oaates for the basis* His experiments seem to be rendered
orronsotts by his using potash and soda prepared with alkohol.
He assumes that 100 gr. of this potash previously melted for 15
minutes are neutralised by 6l*5 of muriatic acid, and that 100 gr.
Hpf soda absorb* 98 of mariatic acid. But it is to be presumed
461 On the Formation of Acttic Ether from Oraper.
that 100 gr. of potash will absorb 84'^$ of muriatic acid, and I0#
of soda, 120 '5 of the same acid.
Again, BerlhoUet neutralised 100 parts of potash with muriatic
tcid, and obtained 1^6.6 of muriate ins tfsad of ]6l-5y which he
ought to have h^d. This difference is partly owing to'tbe water
contained in muriatic gas, but some of it may also be attributed to
the water contained in the alkali employed, which had been pre-
pared with alkohol, and contained 27 per cent, of its weight of
water. This serves to explain the very different statements of thf
composition of muriate of potash, as given by BerthoUe't, Richter,
and Kirwan.
It is necessary to observe that the experiments in which soda
was employed were more carefully made than those with pott
ash. On repeating the latter, it was found to contain' 95 per cent,
of water ; so that it differs but slightly in this respect from soda*
In the report given of this paper to the Institute, it appears thfLi.
Berthollet had himself found since that potash prepared wit^
alkohol contained 13 per cent, of water; after 'hkvifig been ejc-
posed to a red heat, but that these experiments had only been,
communicated to a few friends.
' 06#(rrp<rfto«s.— The experiments in this paper are very imp6r.
tant, an they fully establish tha fact that the alkalies prepared
with alkohol and afterwards kept in fusion for some time are ndt
to he considered as pure dry alkalies^ and taken as a standard in
•analyses: a fact which is now generally admitted, in consequence
of the present experiments, and those of other cheniists.
wfismfasssaaBsmmmmmmmmammmmmmaasssaamBxsmmst^
'I' I' B'
On ihc lamatwn af acetic Ether in the Cake left m presmg Grapes*
Sy Mr. J}wM,o%vi%.^^AnMak^ dc C/mtie^ vol, 68«
It is but ft few years s^Dce acetic ether was obtained in tht
distillation of vinegar when operated upon in large qufintiUef •
It has lately been obtained from the cake left in pressirig grapes ;
for the purpose of preparing grape syrup. The cake was. pat
ipto a barrel; on plunging the hand into it, a ^w days after.
vrardSj by accident, it was found to be hot, moist, and smelling of
ether.. A part of it was expressed and the liquid distslled; tke
£rst portion that came over was pure acetic ether ;. the succeed-
ing portion was mixed with weak spirit of wine and acetous acid.
It appears therefore that the cake of grapes undergoes bo.th tbe
spirituous and acetous fermentation very rapidly, and on account
Cif their simultaneous action, acetic ether is for^ied^ $Q^thi»t
Esaminatian if ike supposed Rice P^ute of Chinfi. A£%
|by seizing the proper time, this ether may be obtained io Auffi-
tient quantity to answer tbe'demand for it.
03i«rff/ioiM.--This accidental discovery ii of considerable valu«
in tome countries, as it enables the proprietors of vineyards to
derive a profit from their refusi materials, and may eventually
bring into a market an article of great use, and which is Ht pre-
sent rare, at a low price.
ExMrnination of the supposed Rice Paste of ChUa. By Mr. Klap*
KOTH. — jitmales de Chimie, voL 69.
TiiK Chinese rice paste is an artificial production of which cups,
goblets, and similar vessels are manufactured, but its constituent
parts are unknown. Some supposed this ' name was given to it
on account of its being made of rice, others because it resembles
transparent rice. It has been considered as alabaster, chake*
dony, or cacholong, Mr. Kratzenstein, at Copenhagen, has dis-
covered the real fact, and descnhes it as a fusible glass of tfa€co«»
lour of blanc-mange, and which has been pressed into a mould
ivhile soft, as appears from its sharp edges* It scratches glass,
and is much more difficult to cut than marble. Its broken surface
has the appear aice of starch boiled in water, and then dried. In
colour and transparency, it represents alabaster*
Crell did not iind any indication of vegetable or animal matters
on igniting this paste ; the pieces of it were soldered together and
stuck to the retort, but they had not lost their semitranspar^cy
er colour, nor any of their weight.
. The specimen that was analysed, was a two handled cup weigh-
ing 12 ounces, appearing like greenish gray chalcedony, but the
sound it yielded on being struck; and also its specific gravity,
^'3936 prevented it from being mistaken for that stone. It was
soft to the file, broke easily, with a glassy' shelly fracture. It
•easily melted by the blow pipe in a spoon, and when melted on
charcoal, became covered with a pellicle of lead. It com-
bined with difficulty with borax or phosphoric salt, but very
easily with carbonate of soda, yielding in the platina spoon small
globules of meialhc lead. It was not attacked by acids.
- 100 gr. of rice paste igniced'with potash, formed a hardash^
grey mdss, soluble in nitric acid, leaving 39 gr. of silica. Sul-
phate of soda, added to the nitric solution, threw down 55 gr. of
sulphate of lead ; equivalent to 4 1 of oxid^ The supernatant
liqueur yielded on adding ammonia 7 g^» of alumine ; and on ad*
dmg carbonate of ammonia no further change was produced, hence
there is 13 gr. unaccounted for, which were pFob|bly borax, soda^
464 On hrotcn TfcmatitcSy and tuarsi Ores of trouw
potash or some other fluxing material. Rice paste thefefore ap*
pears be a silicious gla^s of lead, rendered similar to chalcedony
by aluraine.
It is probable the Chinese use felspar or petunze instead of pure
alumine, to prepare this paste. A biinilar paste may be formed
from 8 parts of oxide of lead, 7 <>f felspar, 4 of common .whii^
glas», and 1 of borax ; as also from 8 parts of oxide of lead, 6 of
felspar, S of flint, and 3 of borax, potash ^ or soda.
From the great difference in the specific gravity of various
specimens of this paste, the Chinese seem to use no determinate
proportion of oxide of lead in preparing the paste. Some speci-
mens having only the specific gravity of 3*68.— 3*635 — 3*68 —
376«— 3-6 and 375. .
It is astonishing that the yn stone is not known in Europe, as
it is so much. praised by the missionaries, on account of its beauty*
its hardnf(ss, and the sound it gives i^hen struck* The niissi*
onarieK assert the yo to be a natural stone, but from its sono*
vonsness^ it seems to be an artificiul glass. The sonorous stones
which are known, such as clinkstone, porphyry-slate, the
•oaoroas quartz crystals of Pricborn, are not capable of being
ibnned into musical instruments as the yu : nevertheless it can-
not be denied but that a Chinese musical instrument possessed
by Mr. Berlin of Paris, is formed of a black bituminous mar-
ble.
Plioy mentions a black stont as sonorous as brass, under the
name of chalcophonos.
OA^rrro^ioM.— These experiroente of Klaproth have dispelled «
cloud of error in respect to the subject of which they treat.
On hrmcn Hematites^ and marsh Ores oflrm^ Sfc.-^ Journal de PAy-
sique. vol. 70.
Mr. Daubuisson has examined the different kinds of hematites,,
and marsh iron ores, and concludes that they are really cora-
)K)sed of oxide ad maximum of iron, and water, so that they are
of course hydrates of iron. A particular account of his labours
will be given hereafter.
i*i*i
The Supplementary Number (xxvii) with Title, Contents, and
Index, to complete tk^ Sixth Volume^ uiU be puMuhed on the 1st of
March, 1811. ^ "^
OS
PHILOSOPHICAL, MECHANICAL,
CHEMICAL AND AGRICULTURAL
DISCQVEUiES,
Jtl"
f . ' •
ou PFLEMENT, V810.
■' • 1
1
AGRICULTURE.
,y4 (fe^at^ of Experiments to ascertain the daily quantity of bratcri
Muscovado sugarnecessarif to fatten Sheep; to skew its effects and
'Value when so applied^ md to dernonstrate ivhof substance or su6m
stances, sufficiently cheap might he mixed with ity so as to prevent its
ipplicatUm to confsnon usts, and yet render it not unpalatable n&r
pernicious to camnaU which feed upon it. Ry the Rev* Dr. CAUt-
yaiGHT^ — Com. Boarcl of Agn. Voh 6. p. 2.
jLHEfts experiinen^'Owe their exkteoce to. a propos'tion which
Was ariginated in the Parliameniary Distillery Ccioiiiittee i^i
1808;, it was ^here suggested that the. ;dra«^ back upon Sugar
^oiild be alk)wed to the farmer for the pilrposes of agriculture,
•n his tnixtog it with some substauce, which should render it
4ia£t for common uses, in the presence of an excise otlicer ; the
ttiggestian was not eaibodied into any legislative enactment, bat
Dr. Cartwright availed himself of a short interval of lei 'ire to
ascertain how far the proposition might be made available in
furactice. The flock of sheep purchased for the purpose ot insti*
tating a set of experiments to ascertain the lacts euiiiuerated in
the title of the paper, consisted of fifteen two stiea' South down
vrethers, which were bought at Chichester, 24.tb *Vigu«t, 1808;
they were bred upon the Downs, and had been fohifi through
the Sammer, and were in a common store state. > hey were
weighed on the 27th August, and their average weight was
90Jlb, and the price was 35s. per head. For the hrst week they
were folded every evexung, and had half a pi^t of br^n and £t
SUPPL.-^T0L. VI. 3 m
U6 Dr. Canwf^, m fp^fgJJl^ Jfth Sugar.
quarter of a pint of peas' eac'h ;" ahd^ the^satfce was given them
' vhen they left the fold in the morning. In*a week they became
habituated to dry food, and \1)cn to this quantity of bran and
peas was added an ounce of sugar for each; and when they were
familiarized to this, .lhe..uextJUil^Q!ili':w.Xaii\i^iigtlt w£is to
try what different substances might be given in addition to the
sugar, which would net; be^inj1Jrions t^ tk«in,a|id:»'yhich they
would not reject, and whicfi at tte same" time* would spoil the
sugar for all other purposes.;, ^ud h.e. th^u^t it better to try the
experiment with ^he di^erettt >sUhstiiuo>esjL while « the sheep had
access to the grass fields rather than wait till they were kept
jippn artificial.foqd altogether. _^
The substances used for this purpose wereTinseed oft, train Tjil,
palm oil, oil of hartshorn, aesafoslida, iiritie, antimony, and
phai'COal ; .most of them prPVPhfing thp ^ng^r frnm hpJjrtg usPii in
distillation, and all of them spoiling it* for common purposes.
Linseed oil was first tried in tbe.propprtiou of one to thirty two
parts of sugar, and the mixture was given for the first time on
the 17th of September, and was put into one only ot the three
troughs, out of which they fed; Che sheep however eat indiscri*
minately, and apparently with the same appetite the mixture
\irhich contained the linseed oil, as those which had the sngar
only; on the following the quiintity of oil was doubled, and the
sheep continued to fefd upon it. with the same appetite. After
this train oil was given in the same proportions, and with the
$ame, success; and it was supposed from the particular avidity
with which they devoured this mess, that the tr^in^oil, so^far
from rendering the sugar less palatable to tbem, gave it a more
ligreeaMe zest and poignancy. The next experiment was with
assafcetiday in the proportion of one to four hundred and' foity
eight parts of sugar ; part of the sheep begun upon this mixture
immediately, but others hesitated, and when they did feed, it' Wis
isomewhat fastidiously, and the 'troughs wece not emptied quifee
so clean as before ; this experiment was 'suspended at that tiBue,
and a trial made of a mixture of sugar with urine in thepropor*
tion of one part sugar to twenty four of urine, but ao obstacle,
from ^warms of bees devouring the mixture as soon as put into
the troughs, prevented the experiment from being carried on at
the usual hour, and the mixture was obliged to be given to. the
sheep in the evening^instead of the morning ; they were however
no sooner accustomed to the change of time than they fed upon
it as greedily as upon the other mixtures, and there was no
^ reason to conclude that the urine had any influence in abating
their appetites, or was in any degree offensive to them. The
experiment next in succession was with palm oil, which appeared
*very likely to answer the purpose of the experiment, and as far
as the sheep were concerued, it fully justified the expectation ;
^ Dr. Cmiiin'.ighi,'9n feeding SheipwkhSugarr 447
Ant .they did not seem conscious that any variation had been mad«
in their, usu^l repast. The e;cperiment with assafoitida was then
reiiewed^ and the sheep fed on this as readily as on the other
D^ixtures^. it was ^iyen in ihfi proportion of one part to two hun-
dred of su^r,. The next e&pcriment was with the empyreuiaa*
tic oil .of har.tshurn, a substance uncommonly offensive to the
smell; but even this w^s not rejected by more than two or three
sheep, and not b.y them for more than a day or two ; the pro-;
portioii of it was one in two hundred and twenty of sugar, Tar-^
tj^r . emetic, in the proportion of two huudred and forty of sugar^
wu8 afterwards^iven, and produced no ill effect on the bowels ofj
thcauimala. . Dr. Cart^.yright, being convinced from these expe*^
rimeuts, that of the substances recommended for the purpose,
undt for common uses,, and of which he had made the triai^ there^
was none which sheep would reject when mixed with sugar, ia
iproporijons sufficient to answer the end proposed, though.it
might be also. satisfactory to the Board to know in what larger
proportions the oils might be given before the sheep would betray,
symptoms of disgust, . Linseed oil, train oil^ and palm oil, were
given in the proportion of one to eight, and the allowance of
sugar ai the same time increased to two ounces each per day ;
and these .mixtures appeared to be equally as palatable to the
£heep.$is any thing which had been administered, and produced
the same results ; and without producing any change in the stat«
jof the bowels.
On phe 29th of September the sheep were again weighed, and
their average weight was nearly 10^lb,.e?ich, being an increase of
upwards of one fifth of their original weight ; and they were tole»
rjibly fat, though it was the opinion of the person who purchased
them that they would not make themselves fat on grass only
before Christmas. • ;
From the 24th September, to the 22nd October, their allow;-
ance of I'obd was increased, to, a quart of bran per day, one pint of
peas, and three ounces of sugar, ringing changes at the same time
with the different substances,- with which the sugar was debased ;
and this was done t«{) discover the particular sul)stance which the/
nioat relished ; and thnqgli they appeared to be extremely fond of
all, yet if a cunje<?ture might be hazarded, the preference was iii
favour .^IJ^train oil. Dr.. Cartwright however, suggests (if the
practice of using sugar in this way should be adopted) that in-
stead, of employing any^otie of these articles singl^^, it would not
be ij^uadviseable to use a con^tposition of several of them together,
which would be attended with no additional expence ; and he rc-
cojnamends ihat instead o( mixing, for examples sake, four
.pounds Of palm oil. with one hundred weight of sugar, that four
.pounds pf .a mixture were substituted, composed of palm oil lib.
tr^iu oil, i lb, urino.2'il^>, ..emetic tartar 2 02, assafuetida 2Ji gr.
44s Dr. CiariarigU, 6n feeSng Sheep vM Sugaf.^
and oil of hartshorn 28 drops; since in this conip6?ition ara cdm^.
prised an animal, a vegetable, and an empyrumatic m!, a sob.
stance containing ammoniacal and other salts, metallic ealx, and
a resinous gnm ; and the whole e)(pebce of which would not
exceed one shilling and eight pence upcin each hundred weight of
•agar. And he is of opinion that the most practicable way of
manai^ing this business, would be to have only one person or com*
pany in each sea«port^ where sugar is imported from t^e West
Indies, licensed to sel) it in the adulterated state. '
This deuil of the experiments is thought by the author to have
afforded a very satisfactory conclusion, that sugar thus adulterated
itiay be advantageously given to sheep, and itideed to other ani-
mals ; for a horse was equally fond ol it, and both sheep and
horses are known to be delicate feeding aninials co^npared with
cattle.
On the 2ind October the sheep were again weighed, and were
found to have gained an average increase of weight of 151h. each
since the 5?9th September ; they were then taken inlA the house^
and kept upon artificial food altogether'; and one of them appear*
ing to droop, that with two others were sent to the butcher, and
the remaining twelve* reserved for further experiments, and they
had no sugar in their food for several days that thty might be
reconciled to its omission, and might all start fair, and without
kny preference of means.
On the 2nd November they were divided into three classes of
four sheep each, and were weighed on the 12th, when a very ia.
considerable gain was perceived, which was accounted for from
their not being yet reconciled to confinement. An attempt was
now made to adulterate their food with charcoal^ but this part of
the experiment was soon given up from the-difEcuIty of obtaining
it sufficiently pulverized ; bran, peas, and hay, were given to ^11,
and to the iir^t class six ounces of sugar each per day, to the
second class four ounces each, and to the third class none. They
Were weighed every week, and the respective weights of each are
given in the original article, but the increase of weight was not
considerable, and sometimes one class, and sometimes another
had the superiority of iirrrease ; but their progress in confinement
was not equal to that which was made when tLey were at liberty ;
and both those which had only four ounces of sugar pfer 9ay, and
those which had no sugar at all, made rather more progress than
those who had a daily allowance bf ifix ounces, and the ad van*
tage was rather in favour of those who had the four ounces of
sugar per day.
From all the facts taken collectively, Dr. Cartwright draws
the following conclusions ;— -Ist. That sugar may bte given with
great advantage to sheep, if not confined, especially if they have
access fo green ^od, however little that green food itiay be i«
Mr i&chi^ on tiec%&ice cfVrtttieB'fia'Wfdxdoiff^Chvk^^ 8fe. 44^
qatLtiiityi^9. That sugar maybe given to them witfi every ptos-
pect of a benefiHal effect in the qaantfty tA four ounces- per day
tor each sheep :-^3. That st^ar, tsup}>^rng it to be purthased at
ft>ur pente per pound (which it might be if duty free) would at
the rate of four ounces per day be paid for in a return of fiethf
extlosiv^ of the advantage of expeditious feeding, and t^ benefit
to be derived from the manure >-*4 That six ounces per day to
each sheep exceeds the maximum that can be given with the best
advantage to sheep of the size of South-downs :-^5. Tfiat tha
advantage of stall-feeding sheep altogether upon sugar and dry
food, of whatever nature that food tnay be, is extremely problem
riaatical. /
f>6»fnj«fum*.— These experiments have been cofrdtrcteU .with an
accuracy which could only have been expected from a most in*
deiatigable friend to the cause of Agriculture ; and the result is
most satisfactory. It has been fully proved by Di^.TaHwright,
that in a future glut of the market for West Ind^'dpiiddtice, a re-
lief may always be found, if the Legislature think' fit to have re*
course to tt, without interfering with the Distilleries; and dis-
tillation can not in future be set up as the sole mode of relieving
the sugar planter ; it can only' be c0TBidered as a measure of cpm-
paratiVe expediency. The Board of Agriculture, and Che country
in general are under additional obligations to Dr. Cartwright ftir
thest salisfiKtory experiments ; and it is impossible to examin*
tliem in detail without unecjuivOcally asserting to the conciasioiw
iie has drawn from them. Many incidental suggestions are also
interwoven with his narrativte, which may supply hints for various
iroproTements in agricultural' science.
90SS=X89eBSfeSSSS5SB9aBBfi
Communicaiums (respecting what Grasses are mare particular!^
maptedj<QT jklfttt9W grttuns^ wsAtntat for PtotuftfViut^wh^her
it is better alwat^s to mow^ or pasture the groundj or to maw and
• jmtvre it im rotation) bp Mr. William Stxckney. Ctm, Bd.
of AgntuUftre Vol. 6\ Pt.^^
It 18 admihed that the opinions here given are rather the re-
sult of conjecture than experiment; but Mr. Stickney thinks that
meadow fox-tail, meadow fescue, and rough stalked meadow
gr&ss, are sufficient to constitute a good meadow in a moist soil ;
•knt for a drier soil, he would recommend meadow fescue, smooth^*
atalked meadow ^rass, and i^ye grass. For pasture on a moist
-soil he prefers meadow fex«^tail, rye grass, meadow Yescue ; and
inai » Arier soil, rye gaass, meadow fescue, and timothy grass.
450 Oil tie a>mparaihe^ten^4i^,ittftny ofR^oh^ Pigtmuf 4r*-
with a ,8iual1 quantity of rough cock»-foot To iroDstitttte a gooA
meadow he apprehends it i^ desirable; to have an abundant produce,
and of such sorts, as when made into hay, shall be well liked by,
and be nourishing to cattle, and shall produce plenty of after.
math ; and he cpnceives the grasses mentioned- to be of that des«
axiption ; for a pasture, he would select such as push ^rst in the
Springy preserve a rich verdure, and afford a nutritious bite to.
the latest possible period, ^nd he tbiuks it much better always
to mowy'^r ^-al.ways to pasture the same field ; since, when a field
IS alternately in meadow and pasture, some ot the early tall grow-
^g grasses overpower and Aweaken such ass put out a greater
quantity of root leaves ohly, and are thereby more suitable fur
pasture grass ; and the ne\t year thf se grasses will be much en-
feebled ia their growth^ and will much deteriorate the pasture ;
and on the otber hand, wh^n a field is in pasture, those grasses
which grow in a close, in a close thick sweard from the root, will
endeavour to^^ jjrevent the taller Rowing grasses from having an
esUlblishment among tbcm^ and thus injure the field tor meadow ;
from which, ha infers that by attempting to have alternate meadow
and pasture, we ar« deprived pf having either in the greatest post
sible perfection.
' O^fervolioar.-*— These observations respecting adapting the kind
of grass employed to the. particular purpose for which uie field is
designed to be appropifated, throw much light on a subject,
which has been too much neglected, and in the i^prosecution of
which great improvements in knowledge may be confidently
looked for. Too little attention is paid in almost every instance,
in the conversion of arable into permanent pasture, and the good-
ness of the pasture at a future period, is frequently sacrificed for
the sake of a corn crop which only protects and nourishes weeds.
. J'hfi hints ia this paper respi8tijig..lbo seljeetkasbe^toflseg merit
attention.
<""'■■>'' 1' "■ ' It iiJIJ! ■Jl .liJin I iJ iiljlp'liM ■ \mmm
CommuTiicatitms rtfpfctivg ike .smnparaipve Ben^t^or Injury to the
Farmer, from Rooks, Pidgeons, Sfc.\ B^ Mr* Wii;LiABf Stick -
•'SLY. — Communications f» (^^ Board of AgrioiUturt. Vol, 6.
Part 2. *,, .. . ■ •
T^ls paper contains, an ^cc^unt of some agricultural discus*
■ sjons at a ^rieel^irig of the lidlderness Society. Mif, Sticks^
/maintains th^t varioas kinpls of bir^, such as rooks, pjdgeoiitf
f fc[)ctn6ws, &c. whose destruction is eagerly sought ^j theJarmer,
**»io more' beixefit by deyouring^ips^ts th^n balances the injttiy
U V
Mr, Crhnp 'in the prbduce <f his Cow*' 441
Visitig'from their ravages on -the corn. With respect to rooks,
lie had oi^clered one to be shot Avhen coming laad^ with- food for
-young,- and he found in the, hag beil^th the beak 33 grubs of the
tipula kind (sometimes ca)lftd tam»taylors), end from subsequent
•ubaei vailuiia seilled the averug^ number of jouraies.to each neat
'^n a day at 7H^ ; from which he concludes that one . family of
;,rooks will consume S96O grubs everyday, or 1,445,400 in a year;
lind supposing that one grub would destroy four square inches of
forn^ .a family of rooks would then devour as many grubs as
would destroy 3 roods 27 perches of corn. He then proceeds to
notice various kinds of birds, and gives their usual food from
Bewick's Natural History ; and thinks it would be to the advan-
.tage of the agriculturist to proiiiote'tlie increase of those birds,
which feed on insects, and yet do not destroy the corn.
y
Observations. — The feathered race of depredators in corn fields
have found a very earnest, and, on the whole, a sensible advocate
in the writer of this paper; but we do not conceive that he will
be able to snatch them from the penal coasequenees of their un-
' authorized intrusions, unless he can rest his arguments on tlip
firm basis of experiment, instead of building it on the tottering
pillar of speculative calculation.
9«
Further Cornnmhication^ Jrom Mr, Cramp of Leves, respecting the
Produce of' bis CofW.^^Cam, Bomrd of Agri, Vol. 6. Part 2.
The previous communications on tbis subject being noticed in
our previous volumes, viz. vol. 3. p. 403, and vol. 4. p. 488, the
account would be incomplete without adding the contents of this
paper; 'It appears that from the/Gth of April, 1807, wheu efee
calved, to the 4th of February, 13^08, she produced 675 lbs. of
butter, which was sold for 49I. ps. 2d. and 5107 quarts* of milk,
vtrhich brought 211. 5s. 7^-; her calf was sold fm* 52b* 6d. and
the dung made' was valued at 31. ; the whole produce then was
^ 7€l: 7s. 3d. andnheesqpenfce of herfhaintatnance'bfendgdlU 14s* 8d.
the net profit was 511. ISs. Id.— In the followiDg year (1808)
fihe calved the tSd of April, and was milked to the 13th of
February, 18Q9> ^n which time the produce was 466lbs» of butter,
and 3753 quarts of milk ; the dung was valued t^e same as the
preceding year, and the calf sold for 36s. The net proiit tlus
year was 29^* l^s. 7d.
(^ervatioTiS. "^The vast profit of this singoUriy piodoctive
animal, necessarily calls the attention to the management under
which it has been attained. It may be comprised in the short
remark, that ehe iias been kept in k^ase and carefully nnrscd
4M Dr.FoikergUt,miti^f€rtaiMg^€et^ofQjijuum.
and cleane<l| and fed on the mo»t mi^ritioua. aliment^ bpth dt/
and green. Tke system appears to. jjierit iipitation, hu.t we can
scarcely expect another instance wl^ere a profit of X53I. 14s. id.
will be obtained from one animal in four years.
JEM0y on the fertUizing Effects of Oypsum in the Umted States ef
America, xvith a View to ehiciaate its mi/sten'ous Operation ^ and
io extend its Benefits to Enghndy and other Farts of ihe British
* Dominims, J5y Mr. A. Fothergill, M. D. F. R. S, of Phi'
ladelphia.'^Com, Board ofjgri. Vol. 6. Part 2.
Gy98UM» the alabaster of the ancieotSy and the plaster of
Parts of the moderns, is said to be found in various parts of the
world, an4 certainly in England and Ireland. It is represented
to be a compound fossil, consisting of 30 parts of sulphuric acid,
32 pairts of pare calcareous ^arth, and 3S parts of water.; that it
requires 450 times its own weight of boiling water to dissolve it,
and loses 20 per cent, by calcination.; and in that state, when
incorporated with water, forms a composition for modelling and
ftatuary, and yields with sand a cement impervious to water*
It is precipitated by fixed alkalies, but not by the volatile; it
does not eiTervesce' with acids, and powerfully promotes putrg.
faction. It is remarked, that though these properties appear to
Indicate a Tery unfavoerabte 'Sttbsmcei for maauit^.yet .ittist
plants on analysis yield gypsum. Its fertilizing powers were
discovered m 1768, in Cbe canton of Berne, by a Mr. Ut|(er,
who liberally disclosed the toeret to the neighboorisig fatmers,
who were soon convinced of its efficacy by experiment. From
Swilzerlaad its fame spread through Germany, and was comm.u«
nicated by tbe Qtrmaos to tbeir friends in Pennsylvania, where
Judge Peters subjected it lo various trials oa different soils, sknd
communicated to t|pe public the result of his experim^iits* This
broeght ft into genersd notice in America : and though some has
been discovered ia the stave of New York» 'ye|'|nMch is still im-
ported fron France and Nova Scotia ; and such is. the increasing
dliniaod, thatH-iicarri<9d more than a hundred, and fifty miles
by land carriage from the wbcucfs on tbe baaks of the Delaware.
The mode of prcpaiing it for use is to first pound it into yei^y
small pieces, and then grind it in a .mill so as to measure
twenty 'bosbtls, or more, per ton ; but the mill stones employed
for t^is purpose should not be afterwards used for grain. Six or
seven bushels are said to be sufficient for an acre, and its fi^rti-
lij^ing effects to last as many years, tbouch sometimes not
very appareiit till the third yc^; soixi^ apply. a single bushel
every year, witb an entire iatsrmissioa every fourth year,
while others tbiak two bufthela annually but a small propor-
tion ) mi thi naore foaly tbs gypsum ^ {>owdered tfie umf
io, its operatioB, but the Ie4a4ura&)e. The mode of uttog
^t is to moisten tbft s^ed grain Mrilb water, and then roll it in the
pulverized gypsum, which is called coating it,, in which state it
is sown in the ordinary way ; and when used as a top dreesing it
is stiewfd hy the h^uid in the sam9 manner as s^, but this is
thought to be a very uncertain mode of application, and the drill
husbandry is recommended as the most equal mode of distrihatiiig
the coated grain* Some agriculturists are of opinion that gy{>>
eum ought not to be applied during the cold winter, while plants
are in a torpid state, but th^t the first sprinkling should be given
when the shoots begin to appear, and a second when vegetation
as more vigorous, but not too late in the season; while otheas
prefer the winter season, and apply it even when snow is (Hi the
ground. Judge Petvrs is said to be of opinion, after 25 years ex*
perience, that the soils to which it is most congenial, are the
light, dry, sandy, and loamy, and that it yields no benefit on
strong clay; that it succeeds best after stable manure and green
crops ploughed in, and promotes the growth of leguminous crops
and all garden vegetables, but particularly red clover, s^id that
it should be applied from the beginning of February to April,
and will-succeed best in foggy weather ; that as a top dressing it
is most beneficial in the spring ; that it answers well after hme
and alkaline manures, and it speedily converts straw and vege-
table substances into manure, and by quickening the growth of
grain stifles and overpowers weeds ; and these opinions are con^
' firmed by the experiments of several other respectable American
gentlemen.
The writer admits that o^'ectiow to the use of gl^um have
been urged, but he does not admit them to be well founded. As
to the objection that its application long continued renders the
' soil too stiff for the plough, and, by increasing the resistance,
retards its progress, he remarks that this only prpves that the
application of this species of manure has been carried to excess,
or has been applied to land which did not require it; and as to
its rendering a crop too luxuriant, and that it exhausts the soil
b}' its stimulating power, he observes that top great luxuriaucy
only argues the abuse of a rich manure, and is equally applicable
to all manures ; and so far from being deprecated as an evil, is
more frequently solicited, and may be remedied by early or by
repeated ihowing, and that the stimulating power of gypsum maj
always be regulated by observation and discretion ; and as to the
locality of the benefits which result from its use, he insists that
it has never been known to fail in its effects on proper soils in
any of the states, ef America.
Dr. Folhergill allows, that the cause - from whence proceeds
the fertilizing power of gypsum, is a problem which has never
yet been solved ; aud after noticing several principles to which it
SUPPL.— VOL. VI. 3 k
45i Obiep^atmi &H th Naiural Hisioty of Mart
has been attributed, he deems* the nioart probabW supposition t#
be, that it arises from the power of promoting the speedy dissb^
lotion of vegetables. And as no doubt exists as to this manui^
possessing the greatest fertilizing powers, though the causes maj
not be ascertained, he laments that the use of it has-been hitherto
circumscribed within too narrow bounds, and conceives it to de^-
serve a fair trial in England and' Ireland, «w its success would
crown our harvests with more plenteous creps,= and its feilure
anight add to our present stock of knowledge^ He recommends
Ibe Board of Agriculture to determine by experiments, to be re«
warded by an honorary premium, the fertilizing effects of pul^*
verized gypsum^ on every kind of soil, And' with the respective
kinds of -grain, and quotes the success of - a gentleman near
•Sittingbourne, in Ken^ as warranting- the* most favourable ex.
pectations, '' that the British Board of AgrkuUare may have
the honour of rectifying the opinion of the public concerning this
Taluable manure, of determining its comparative merit, andt final**
ly,of diffusing its benefits throughout^the British diminions/'
Obsertations^'^lt is plain,. from the Board of Agriculture having
given a place to this paper in their aqnual volume of communis
cations, that they consider the subject as deserving their atten*
tion ; and, under such a sanction, there is little "doubt that many
expei'iments will be jnade to ascertain the real importance of
gypsum ia the catalogue of manures^ Its high price in England
must necessarily limit its application, till the mostdecidve ex-*
periments have evinced that the ultimate benefits derived from
its use are^ beyond the expences of procuring it; and this cannot
be ascertained, satisfactorily,, till its application has been per-*
severed in- for at least six' or seven years. :
Cbstrvatians on the Natural History ofMarL By R. G. of 5. Af.
fi ear Perl A^ — Farmers Mag. No. 44>.
- These observations are. rather an account, of a particular
stratum of marl, than concerning thnt substance, in genera), and
the local circumstances ought, therefore, to be notic'ed. The
stratum. alluded to was of an oblong circular form^ of about eight
acres in extent, and . was covered with moss to a considerable
deptl;), being. surrounded on .^11 sides by rx>cky hills. . It had been
Ipng knovyn. among the people of the neigh b«)urhood that this
spot co,nta>ne.d.marI, And.some had occasionally been obtained
in dry summers, near the outside ; but at length the proprietoc
determined to cut a mine through the lock^ on.one.side, in such
a direction as to drain the whole. And.since this has been com-,
pieted, a section of the marl is laid open, from which it appears
I
Dn the Use of Sea Skelb a$ a Manure^ ^^
ttat the stratum near the outside is only a few inches in thicfk*
toess, but gradually increases to several feet, by the time it
reaches the dry pari of the moss, when it terminates rather sud-
denly, without much decrease in thickness. The mg.rl did not
extend over any considerable space in a regular bed, biit was
found in troughs or basins, of^ ten or twelve yards in diameter,
some connected, and others detached, by an intervening bank of
clay «r sand, similar to the substratum of the marl;
From these appearances itii inferred that the niarl^bothin tWi
mine and the meadow, had been deposited froni water, and that
the springs which rise out of the hill, and cross the basins must
have been the source of the marl, which, being carried down by
the water in an embryo state, tad, by exposure to the atmo*
sphere become a calcareous coat on the surface of the water, and
descended, by its specific gravity to the bottond.
Ma*
Observations. — This conjecture, as to the formation of marl,
may be well founded in this particular instance, because the ad-
joining hills might afford the calcareous material, which was
afterwards deposited by the stagnant water; but the principle is
t«o limited to admit of vniversal application. A recoVlectibn of
the circumstances recorded in this paper mayj however, frequenl-
ly lead to a search for this useful substance, where its existence
would not have otherwise been suspected^
jji' 'I Eggggaggg? '"> I'n ' ■ I ggsggggsgsgBaggssa
. On the Use of Sea Shells as a Manure. By Domesticus. —
iarm^rs Mag. No. 44.,
The benefit derived from sea shells as a manure, is universally
admitted, but the difBculty of reducing them to a sufficiently
pulverized state, has much narrowed the use of them. Tliis
writer states, that a gentleman, whose farm is situated near some
banks of shells, which are obtained in a more or less broken
state, has much hastened their reduction to powder, by laying
them as the bottom tier of his dunghills, and throwing upon them
the dung of his stables and yards, by which means he finds them
almost, entirely pulverized, when -the time arrives fot* carrying
them to the field. This discovery was made by an accidental
circumstance, but has been regularly pursued from ai conviction
of the beneficial results,
Mb
Observations. — The practical advantage derived from this me-
thod of treating s<^a shells, will recommend it for adoption to all
^mers who live near enough to the <q^X. to obtain them ip a
k'pBgh state.
3 N
( 456 )
Oh Kuta Baga* By a N^humberlaiuf Farmer, -^Farmers Mag4
No. 44.
That important article of spring food for cattle and sheep, the
Swedish turnip, which, indeed,' seems to be the only vegetable
food that can be depetKkd upon to fill up the chasm between the
failure of other turnips and the coming of grass, is stated in this
paper to have been first introduced into Scotland from Sweden, about
twenty-four years ago, in consequence of the publication of a tour
through Sweden and Denmark, by a Mr. Joseph Marshall, who
was acquainted with Linnee ; and the conductor of the magazine
gives a quotation from this work, in which it is asserted to have
been introduced into Sweden from Lapland,
Ohervations.'^^Withoui subscribing to the accuracy of this ac«
.count of the first introducticm of the Swedish turnip into Scot-
land, we may say, that much information relative to the history
of this valuable plant will be found in the travels of Mr*
Marshall, which were published in 1772.
Ohnvahans m ike r4nsing ^f Twmf Seed. By J. G. F«— -
Farmers Magazine, No. 44,
Th£ difficulty of obtaining good turnip seed, induced the
writer to raise whatever he might want for his own use^ and for this
purpose he allots a corner of his garden, large in pi*oportion to
the quantity of the seed that may be wanted. About February
lie selects from the field such turnips as seem of the most nutri-
tive and durable kinds, and transplants them into this space in rows
' from twelve to fourteen inches asunder, putting tbem pretty close to
each other in the rows, and covering tbem nearly over with the
mould. Great care is stated to be necessary to prevent the birds
from destroying the seed when it begins to assume a blackish
colour, which, in favourable seasons, takes place by the middle
ef July ; and it should be gathered before ii is dead ripe, and tied
up into bunches to dry previous to the winnowing.
Observat ions. '^These useful directions for raising turnip seeds
merit the notice of every farmer, who would not expoi:e himself
to the disappointment which too frequently attends the placing
entire dependence upon the seedsman for the goodness of this ar^v
tide, lor the first sowing can never be lost, without great hazard^
as to a crop*
( 4S7 )
tmmimmm
(hi the adtwt €f f%np Smt. Bp v Frimdto Ska 8mb^-
Farmers Magazmcy No. 44.
Tb£ point contended for bj the writer of this ftrtiele is, that
a flax crop i^ not more injurious to the ground than ^anj others ;
and, he considers, that the premiotire oflfered by tbfe Board of
Agriculture for the cuftivation of flax, so far from having pro-
moted, have rather tended to prevent that 'object, inasmuch s(S'
many have been induced, in leasing' their. lands, to introduce
clauses of restriction against the cultivation of that artivle. He
proposes that the Pctth^hire farmers, who hav^e long cultivated
flax, should be called Upon for their Opmioti on this point-; and
that a full experiment should be made in a field, of ground of the
same quality as to soil and manure, part of which to be under
turnip, beans, cabbage, &c. and the remainder under flax ; and
in the succeedrtig years the san)e field to be sown with ba;riey or
oats, &c« and thu« try the difference of thelsucceeding crop.
■ Ill I I I \m»mimamm
Observations. 'm^yf hen the enormous sums paid to foreign nations
for this article fully evince that we cannot do without it, and
when experience shews that it is every year becoming more
scarce at home, we most c»rdiaHy agree with this writer iha^
"/every one who wears a shirt, and wishes well to hie coiinti^,
should give his support to the culture of flax/'
A fieto Method of yoking Horses in Thrashing Machines. By Mr.
John Gladstone. — Farmers Mag', No. 44.
It is extremely difficult to convey any adequate idea of this
mode of yoking horses to machinery, without the assistance of
Umj plate which accompanies the original ' publicatiori. It
consists, however, in yoking the horse not to the shafts in the
usual manner, but to two lines passing over a pulley in such a ■
w»y as to raise a weight, which may be encreased at pleasure ;
and thie intended effect is, th^t the machine should be impelled
forward by the po^er of the weight ia addition to the power
of the horse ; a«d the weight is so contrived as to remain sta«
tiooary on a platform, when the horse stands at rest.
• • I
Observations. — ^Tliis attempt of Mr. Gladstone discovers much
ingenuity; but We cannot recommend its adoption without prac*
ticiil proof of its utility i for tt appears to us. that the assitslance .
45S On He CuUwaiwn of troeiuni
which the horse derives from the weight in impelling forward the
machine^ is just counterbalanced by the exertion he aiust xaaki
in order to raise it*
' -.1
On Reaping Machines, By A. S^— Ptfr/werj Mag, No, 44,
Mention is made of a machine for this purpose having been
invented £ind used in Scotland, but no description or account of
it is given ; however some'notice^ of similar machines are copied
from the Roman agricultural writers*
Observations. --^It is scarcely possible to assign any other mo*
tive fpr the publication of this paper than to excite expectation,
with a previous^ determination to disappoint it.
On Horse Language^ By a Turner, — Farmers Mag, No. 44.
This paper recommends that the languages employed on »
farm in the management of horses should be simple and uniform,
notwithstanding any change of servants to whose care they are
committed, since it is much easier to teach a new language ta
a servant than to a horse.
. Ohseroatums,*^Vft fully concur in the recommendation of the-
farmer, from a conviction of its practical convenience.
■!»f.,.. " . i ggBSBMBeaaeaagaaag ,i. ji
HORTICULTURE.
On the Cultivation of Crocuses j with a ,short Account of ihe^fferent
Species known at 'present. By A. H. Ha wort, Esq. F, L, S,
and H, S»-^Trans, of the Horticultuial Society, Vol, 1. pt, 3.
The writer states, that not fewer than thirty seasons have re-
volved since ♦these vernal beauties became the objects of his hor-
ticultural assiduity, and that every succeeding year has added
something to his knowledge ; in the course of that time he ha»
collected seeds from the blue, the purple, and the white flowering
kmds; bujt has never obtained any from the yellow.
In treating of the culture of this beautiful flower he remarks,
that from the sowing of the seed to -the maturity of the plant,
occupies a period of from three to four years, and that the seeds of
the crocus, like those of all. other bulbous plants, should be
l^s^thered as s<M»n as they have rip(;ued, which is denoted hy the
^ .
On the CuUivation of Crocuses. 45A
partial splitting of their capsules at the top, as well as by their
)>aie and dry appearance,; and this usually happens in the montb
of June. It is also noticed that the. capsules of the crocus are
formed in a manner widely different from that of most other flow.
crs ; for they are not visible in the base of the flowers at the time
of flowering, being at that period hidden far beneath the soil, near
the very bulb, at the base of the long tube of the corollar ; and it
is not until after the total decay of the flower that the swoUeu
capsule emerges above the surface of the earth.
* The seeds of crocuses are directed to be sown imi)iediately
after being gathered in light dry earth, that will neither bind
nor retain moisture long, and in large pots or small shallow
Iboxes, with a sufficiency of boles, and pot-herbs laid at the bot-
tom, for the purpose of draining off, with certainty, any super*
4uous moisture, and to be scattered thinly, and not covered at
the time of sowing more than half an inch with the mould. The
inost eligible aspect for the seed boxes, until the autumnal rains
commence, is said to be a moderately shady, not unsheltered
bne, wh^re they may receive all the influence of the weather,
except such heavy showers as would wash bare the seeds,
^s soon as the rains commence it is recommended to re-
move the boxes to a warm situation, and to protect them
from excessive rains, frosts, and snows, by the occasional
shelter of a garden frame, ^vith, however, the benefit of the full
air at other times, but moie especially after the seminal leaf
protrudes its point above the surface of the earth, aud this
'sometimes takes placi? about the end of the year, but oftener in
the earlier spring. After this they should have complete expo-
'sure to the air, even in frosty weather, being screened, however,
occasionally, like earl}* radishes, with loose straw, to prevent
their being raised out of the ground by the effects of frost ; and
in this manner they may be treated till the increased power of
the sun renders daily watering necessary, when it will be found ad*
vantageous to remove them to a cooler, but not sheltered situa-
tion, where they may remain till their leaves lie down, giving them
eueh loose-wateriiags, when the sun is not on them, as they ap-
pear to require. After' the decay of the leaf they should be de-
fended from all humidity,' except dews and gentle rains, till the
end of August, and the earth should be occasionally stirred m the
boxes to admit new accesses of air towards their roots; and
in case they stand too crowded, some of the plants may be
transplanted the first »utumn into other boxes, and the seed
plants will require a small addition of fresh mould to be sifted
over them. The second season requires the same management
as the first; and as soon as this year's foliage has passed away,
the ro*ts should all be taken up and replanted again, the same
ijir the following day, into fresh eai th of the same kind as before.
A&O On the Culture of tie DaUu
at about an inch deep and as much apart ; and the third 9ea99a
requires no change in their management, only sifting ovef ihtm
in autumn half an inch of fresh earth.
If they have been duly attended to for three seasons, most of
them will shew flowers in the spring following, in the midst qf
the fourth cup of leaves, and fully reward ail the preceding ass^
duity and care. And the seedling plants, after they have flowered,'
xnay, to all intents and purposes, be treated as old ones; and
after their leaves have once more passed away, be taken up and
r^.planted in the open borders of the garden, at about two inches
apart and as many deep, in any way or shape thought most de-
sirable.
When the old roots are taken up (and it is advised to do this
every third year), to part and increase them they may be kepjt
out of the ground till Michaelmas, but not later; and the time of
their flowering may, within certain limits, be regulated by the
time of their planting, for the later they are planted, the longer
will they be before they flower in the spring.
An accurate botanical definition is then given of thirteen dif-
ferent species of crocus, which are stated to be all the species of
this genus known to the writer, and a plate is given in illustration
of the peculiar formation of some of the parts of the plant.
Oiserufl^/o/w.— This paper may be considered as a very com-
plete account of one of the most beautiful flowers which announce
th^ return of the spring, and whieh is so great an ornament to our
gardens! And though the crocus is not commonly propagated
froni seeds, but by parting the bulbs of the roots when they are
taken up in the summer, yet we recommend the gathering of the
seeds and sowing them, as the only means of obtaining new va-
rieties of so beautiful a flower ; and the ultimate success will be
found to amply repay the care and trouble expended in the pro-
secution of the desigu.
Observations on the Culture of the Dahlias^ in the Northern Parts
of' Great Britain, SfC, in k Letter to R. A. Saltsburt, Msq,
jBy JoHK Wedcewood, of Staffordshire, Esq^-^Transactkms •[
the Horticultural Society » VoL 1 . Part 3.
These beautiful flowers have heretofore been considered as
not suflficieritly hardy to bear the open air in England;
but Mr. Wedgwood thinks that they are about as hardy
as the potatoe, and he has no doubt that they may be quite ' na.
turalized in Devonshire, where the climate is much milder than
in Staffordshire. For /in 1807 he became possessed of three
plants of different varieties of the dahlia sambuci folia, which
On the Culture of the earJy purple BrocoR. 461
^trt in pots ; in the middle of the summer he planted them ia
an open border in the garden, in a clayey soil, where they ^rew
very fast, but they had not flowered by the middle of September,
V^hen a sharp frost entirely destroyed their foliage. They were
then taken up into pots and removed to a conservatory, whpre
they vegetated through the winter, but without any appearance
of flowering. In May, 180S, they were again planted out in
a border on loom, enriched with rotten leaves and dung; one of
them grew rapidly, but the other two had suffered a check, and
had lost their main stem ; they also produced buds, the first
luxuriantly, and the two latter more sparingly ; and when tsikea
up for potting on the ijpth of September, those which had pro*
duced scarcely any flowers, were found to have many large tubers
adhering to their roots, in the same manner as the tubers of th6
paeony ; but that which had flowered so abundantly, had not
produced a single tuber. The tubers, when separated, promised .
each to produce a flowering plant in the next spring. . Some
ripe seed was also obtained from that which flowered, by drying
the heads, gradually, in a hot-house, after they were gathered^
upon being cut down by the frost.
Observatt'ons, ^"^These directions for the management of the
dahlia in the open air, will be lound interesting to every lover of
a flower garden, who is anxious of adding to the nirmber , of
exotic plants already naturalized in this country.
»•*«
Hints relatwe to the culture of the Early purple Brocoh\ as practised
in- the Garden ^Daniull Bcal, E-sq, at Edmonton ; by Mr*
John Maker, F,H.S. Transactions of the Horticultural Sb,^
ciety. Vol, I. part 3.
This Brocoli which is said to have been introduced into this
country from the cape of Good Hope by the honourable Marma*
duke Dawnay, has been sold for two years by Mr. Grange of
Covent Garden. The method of cultivating it in Mr, Beale's
garden is thusr described :— Three crops art sown annually in the
middle of April, May, and August, aud these si^ppiy the family
from September till the end of May. The seeds are sown very
thin in a ^border of rich light earth, and are carefully cleaned
from weeds : in about a month the young plants have eight or ten
leaves, and are then finally planted out at the distance of two feet
every way in a pieqe of sandy loam, which has been prepared for
the purpoae by digging, and enriching* it with a large proportion
of very rotten dung, frequently turned over for the purpose of
picking out every grub and inject ; the ground is kept coastantlj
Spppj..— vpj.. yj. , 3 o
.462 ^n account of the Burr pinot AfpU.
clean by . hoeing, and the looie surface is drawn together in a
heap round the stem of each plant; thi^ treatment is for the
crop sown in April. The second crop is treated in the same man-
ner, but that the weaker plants are left in the seed bed for eight or
ten 'days longer to gain more strength, whfn th«y are trans-
planted into pots, of the size called raxteens, filled with compost,
and are placed in the shade ; and H the plants are duly watered,
they grow freely, and are then plnnged into the ground, in the
pots, at two feet distance from eacti other, and rather below the
level ; ai^d by the time the pots are full of roots, and the Autum-
nal rains have rendered watering unnecessary, the holh'ws round
the stem are filled up with mould, which is firmly pressed down ;
and on the approach of settled frost m. December or January, all
the pots are taken up, and removed to a frame, pa, or shed,
vhere they can be skeltered from the extreme se\erity of the
winter and ;yet have air when it is milder ; and in this mauoer a
supply is preserved for the table in the hardest winters. The
third crop is sown in a frame, or under hand glasses, and is
treated in^ the same manner as cauliflower pints through the
winter ; and from this crop the seed is obtained, and the neces-
sity of removing from the seeding plants every other plant in
flower of the cabbage kind is strongly inculcated; and much sttess
IS laid upon the precaution of potting brocoli immediately from
the seed bed, as if it be transplanted oftener, tht head is less in
aize and sooner runs away to seed.
■ ■ > ■
Observations. — The practical directions given in this paper
Lave been minutely retained, because they are the most useful
parts to such as interest themselves in the improved cultivation •f
culinary vegetables.
jlit Account of the Burr^Knot Jppie» In a Letter to Hk«|it .
Geimstone, Esq, by the Rev. Joiiir Simpson. — Tramactions of
the Horticultural Society f VoL \, part ^.
This Apple is propagated by putting a few knots or knobs of
it into the ground, which will make a long shoot the following
Spring. The Tree is stated to be uncommonly productive, ^nd
never to miss bearing, nor to be so liable to blight as other varie-
ties. The fruit is large, and resembles in its tints the JUbstitt
Pipptn, and is not inferior to the Codlin for all culinary purposes.
The wpod is not liable to canker, and this is attributed to its not
putting out any tap-root, but spreading its numerous fibres from
the knot horizont^ly, and following the richness of the soil,
and fruit is frequently produced upon plants of one year's growth.
\
OnikeConstrudionqfSotmdedPramts. 4^5
(06wrt<?f/o?w.— -If thii Apple had possessed but half the good
qualities enumerated in this communication, it would have beea
highly deserving of general culture ; much more so then since
possessed of all the advantages mencioned by Mr. Simpson, It is
to be regretted that no place is pointed out, where it may, be
procured.
0/f the Horticultural management of the Sweet or Spmiish Chesnut'^
Trecj by the Ri^ht Hon, Sir Josei<h Banks, Biirt. K, Jtf.
Transactions of the 'Horticiiltural Society^ Vol, 1. f>art S.
It is stated that in all the northern parts of Europe, whose
chesnuts are used for food, the practice rtf grafting the trees that
bear tbera has been known from time immemorial ; and though
it has been little practised in England, yet is not known in Devon,
shire, and other western counties, where the nursery men sup-
ply grafted chesnut-trees. Sir Joseph Banks planted some of these
about sixteen years ago at Spring Grove, but they were neglecte4
at first by the gardener, and did not produce fruit for six or sevea
years ; since that time however, as the tre«*s have increased in size,
the crop has become more abundant ; and though they are ojoly
six in number, they afford a daily supply from the beginning of
November till after Christmas. The nuts are described to be
much smaller than the Spanish impoil;ed fruit, but beyond com-
parison sweeter to the taste ; the crops are little subject to injury,
and^the trees are in general covered with blossom in a proportion
injurious to their growth. The kernels of the fruit are allo.wed ta
be more liable to become dry than Spanish Chesmits ; but thift
ma^tr be guarded against by keeping the nuts always . in a
cool place, rather damp than dry, and putting them into aa
eaithe'n ware jar with a cdver, which will keep them ceol, and at
the same time restraih the loss of moisture without entirely pre-
venting perspiration, and thus endangering the loss of vitality.
Observations ."^Vit are fully aware of the advantages derived
from grafting the chestnut tree orl 'the Continent; and we do not
See why the same practice should not be extended to it in this
country, as welt as %6 the apple and pear ; and every conclusion
ivom analogy warrants aa equid expectation of success.
9BSSSBSS. '■ J ■ '1 '. ■■ T
On the, proper Cbnsiructhn ofHot-ibed Framet* % T. A. Knight,
Esq, F. R, S. SfC. •'•^Transactions of the Horticuitnral Society*
F^oL Impart 5.
Thi want of improvement in making hot-beds is attributed t»
the general unwillingness of gardeners to admit that they are defi-
464 jfccoutU •J the Domdm l^ippU.
cient in information in this particular. The usual mode of making
the surface ^of the bed horizontal, and giving some degree of ele-
Tatioh to the gUjss at that end of the frame, which is towards the
nortti, iS> represented to be a much less perfert mode of construc-
tion, tl^eii pi. rciug the hot<bed on^an inclined plane of earth, ele*
vated about fifteen degrees, and adapting the form of the frames
to the surface of the bed. This mode has been practised by Mr.
Kinght for many years with the completest success ; and he has
also frequently used with great success, a frame and hot-bed thus
formed for forcing grapes, by placing the bed at three feet dis-
tance frora the wall, to which the vines were trained, and intro-
ducing their branches into the frame through holes made at the
north end of it, as soon as the first violent heat of the bed had
subsided ; and he thinks that if an inclined plane of earth be sdb-
iBtituted for the hot-bed, and vines be trained in a frame adapted
to it^ the Chasselas grape would ripen perfectly in August*
Obsercaiiens. The attention which Mr. Knight has for 89
itnanj years paid to Horticultural Science, and his great acciiracy
and experience, entitle all his observations on this subject to
great attention. The suggestions in this paper respecting
the formation, though the least complicated^ are some of the most
Taluab\/s he has given to the world.
mH^^^m^Sim
A short Account of a new Apple^ caUed the Dcnvnton Ptmin. By
T. A. Knight, Esq. F, R, S. — Transactions of the HorticultUm
* ral Society, VoU 1. part 3.
This Apple has. been raised from seed by Mr. Knight,^ in,imi*
tation of the Golden Pippin, its male parent ; being formed by
mtroducing the pollen of this variety into the blossom of an ap^
pie provincially known by the name of the Orange Pippin ; the
trees of both varieties having been trained to a south wall for the
experiment. The Downt^n Pippin is said to be deemed, in Here-
fordshire, an excellent cyder apple, and the hydrometer, as well
as the palate, indicates that it holds in solution, a large quantity
of saccharine matter. The trees of this variety grow rapidly,
and the fruit ripens earlier than the Golden Pippin.
Observationsm-^ln the present failing state of that excellent
table fruit the golden pippin, we recommend the new variety
xaised by Mr. Knight, as the best sibstitute that can be planted
to supply its place.
iSi
» III I I I • t »i ■ .1.. I. . ■ .. . III.-
On the Mcnagemmt of the Omotu By T.' A, Kkig^t, Es^m
jP. K. 5, Sfc,''-^Trfmsactiotts of the Horticulturql Society. Vol» 1.
. parts,
. 4
With respect to the gtowtb of bulbous rooted plants, it is no-
ticed that these generate in one season the sgjp or vegetable blood,
which composes the l^eaves and roots of the succeeding spring ;
and wheii'the sap is accumulated during one or niore seasons, it
is ultimately expended in the production of the blossoms and
seeds; and as the reserved sap composes in a great measure the
bulb, so the quantity accumulated, as well as the period re«
quired for its accumulation, varies greatly in the same spe«
cies of plant under different circumstances: thus the Ouion ac-
quires a larger growth in one s«ason in Spain and Portugal than
in England. Mr. Knight however, has practiced for two years a
mode 4>f xulture;^ by which in two summers in England, be {nihi-
^uces on onions nearly the eilect of one in Spain and Portugal.
The seeds of the Spanish or Portuguese Oiiion are sown at the
usual period of the Spring, very thick and in poor soil, and- gene-
rally under the shade of a fruit tree ; and in such situations the'
bulbs are seldom found in the autumn much larger than a pea*
They are then taken up and preserved till the succeeding spring,
when they are planted at equal distances, and afford plants, whicii
differ from those rai^^ed immediately from seed only in possessing
much greater strength and vigour, owing to the quantity of sap
previously generated ; the bulbs often exceed five inches in dia-
meter ; and from being more mature, are more certainly preserved
•ound during the winter.
OhserccUions, '^The mode of culture recommended in this paper
for obtaining l^rge and fine onions is so very easily practised, that
Vfe cannot but recommend its geneial adoption*
jin improved Method of cultivating the Alpine Streewberry, By
T. A. Knight, Esq. F. R. S. — Transactions of the Horttad*
lural Society. VoL I. part 3.
The seeds of the best alpine variety of strawberry were sowo
in pots of mould in the beginning of August, the seeds of the
preceding year having been preserved to that period, and the
plants which these produced were placed, in the end of March,
in beds to produce fruit; the lexpi^riment succeeded tolerably well^
466 On some new XHirieties of the Peach*
but not quite to the satisfaction of the author ; he, therefore^
tried the experiment of sowing some seeds of the same variety
carl^ in the spring, in pots, which were placed in a moderate
hot-bed, in the beginning of April, and the plants thus raised
placed in the open ground as > soon as they were of a sufficient
size : they began to blossom soon after Midsummer, and to liptn
their fruit towards the«end of July, affording an abundant crop
of autumnal fruit, as late as the second week in December.
The success of this' last experiment has induced Mr. Knight to
recommend the annual culture of the Alpine strawberry in the
fan)e manner.
Observations, — As a mode of supplying the table with straw-
berries, at a season when they are not otherwise obtained,' the
mode of culture here recommended is worthy of attention, but
for general crops will not supercede the old method.
On seme new Varieties a/ the Psach. By T. A, Kdhght, Esq,
F. R. S, Sfc. — Transactions of the Horticultural^ Society , Vol 1,
part 3.
Mr. Knight remarks that in his efforts to obtain new va*
rieties of fruit of other genera, he had reason to conclude that
the tiees, from the blossoms and seeds of which it is intended tqr
propagate, should have grown at least two years in mould of
the best quality ; and that, during that period, they should not
be suflered to exhaust themselves by bearing any. considerable
crop of fruit, and that the wood of the preceding year should be-
thoroughly ripened ; and if early maturity in the fruit of the new
seedling plant is required!, that the fruit within which the seed
grows, should be made to acquire maturity within as short a
period as is consistent with its attaining its full size aiid perfect
flavour. With these preliminary cautions he pro{>a.gated a va*
riety of the peach from the, large French migiion, and the little
red nutmeg, using the stigmata of the former and the pollen only
of the latter ; and three peaches only were allowed to remain
on each tree. Of the new varieties' thus obtained three are
stated to be very early, and two of them, in 1807, ripened ten days
before the Royal George, and three weeks before the red Roman
tiectarine, which ^rew on the same wall, and adjoining to the
seedling trees, the fruit was also much, larger, and soft and melt*
ing,. and the flavour was equal to that of any peach known: in the
garden. . The 'success of this experiment having so completely
answered, Mr, Knight expresses bib confidence that the peacU
tree might, in successive generatiooSy be so ^ oaturalizjed anii
OB$ervations on the form of Hotmhouses. 467
hardened to the climate of England and Ireland, as to succeed
well as a standard in favourable situations.
Observations. •'^Tb'is very intelligent Horticulturist is every day
adding to tlie obligations he has already conferred on hisf bounty
in this department of science; and we anxiously wish that the
same enterprizing spirit would inducr other gentlemen to prost-
cute similar experiments.
On the Forcing-Houses of the Romans, xvith a List of fruits cut*
thatm by them now in our Gardens, By the Right Hon, Sir
Joseph Banks, K, B. — Transactions of the Horticultural Som
eiety, VoL 1. fart 3.
This classical paper is equally interesting to the scholar and
the Horticulturist, but is of too miscellaneous a nature, and too
little adapted for abridgen^cnt for us to do more than notice its
merit, and to recommend it to the perusal of our readers.
Observation* on the Form of Hot„Hous€9» By the Rev, James
VViLKiifsov. — Tra?isacti&ns of the Horticultural Society, Fol, 1.
part 2v
It is allowed that more may depend on the management than
en the form of the hot-house; yet the proceeding on something
like principles is strenuously contended for. The principle as-
sumed then is, that the sun's raya should fall perpendicularly in
the hot-house in the spring season, when heat is most wanted ;
and an angle of 45 degrees is shown by satisfactory deductions to
produce this effect in the beginning of April and September*
Observations. — The mathematical deductions, aided by dia-
jgrams, in this paper, fully prove the advantage of changing tb«
usual angle of the inclination of hot-houses, (34 degree^ lor the
angle recommended by Mr. Knight, which concentrates mors
heat both in spring and aatuinn.
< 4*8 )
NATURAL PHILOSOPHY, ARTS, akd MANUFACTORK*
SufpUmtnt to the First and Second Part of the Paper of Experiments^
for Invesfigaiing the Cause of Coloured Coticentric Rings between
Object Glasses, and other Appearances of a similar Nature. By
William Herschel, LX.D F.R.S.— PAa/. Trans. 1810; )
We feel it incumbent on us to take the more particular notice
of these observations, as they seem to be principally intended
(notwithstanding the opinion of " the little club," of Dr* Hers-
chel's friends, tbat with such opponents all further discussion
would be vain,] to serve as answers to our fornier remarks. Our
arguments, it is true, are merely mentioned as objections which
might be made to the experiments : but this seems to be a species
of prophecy not altogether unprecedented, in whi<jh evenis al- *
ready past, are very clearly foreseen ; and we have ' not vanity
enough to reject the omission of a more particular reference^
which the author has probably thought less consistent with the
dignity of the work in which his papers have appeared. We
shall again attempt to follow him step by step, and shall state
his principal arguments as impartially and as concisely as possible*
Sec. 54.—" Supplemental Considerations^ which prove thai there are
two primary prismatic Bows^ a blue one and a red one,^'
We have remarked, (Vol. v. N. 21, p. 410.) that" the red bow
is^'mcrely the converse or the supplement of the blue one'' and tbat
^' tbe.red bow is particularly describei in Newton's Lectione^ Opti-
cal." Dr. Herschel replies, that the blue bow being turned into
streaks jby the application of a plane glass to the surjeice of the prism> -
and being by this "criterion'' shewn to be pi imary, it may be
shown by the same " test" that the red bow whicli he has intro*
duced as a^new phenomenon is also of ecfual originality : and
that the colours exhibited in the Newtonian experiment, are not
the red bow which he has described ; 1. Because the angles which
the bows subsend, and the elevations of the eye required for see-
ing them are ^ different ; whence it follows " that we have two
critical separations essentially different, namely, the reflective
and the intromissive.'* 2. Because the transmitted colours, which
Newton makes visible by the addition of a second prism, cannot
be seen without it," while his own red bow may be seen in one
prism. 3. Because the residuary colours of the Newtoniaa bow,
passing throiigh th^ (U'isnis, c^noi be seen by an eye plaeid
whtn the bin* bow 48 visible. 4. Because tixe ravi which are
transmitud through the space in which the blue bow appears, are
•cattered through an angular apace.of about 9% contiguous to the
base of the prism, and cannot therefore form the red bow^ all the
angles being different in the two c^$es.
0^enatwni»r^jA order that the reader's atteatioii may br the
kas distracted by a ipultiplicity of unconnect:e<i arguments, we
shall take, the liberty of making our reply to each of Dr. Hers-
ciiel'a flections. immediately after we have given an abstract of it*
We are perfecdy ready to admit that both the bows are af sequel
m'igmaliiy; but we nmit still assert^ that one red bow only is ob-^
aervmble, and that this has been conr^eetly described by Newton
as the converse of the blue one. 1. Because^ the angjiesr as well
as tke elevatioa jof the eye, are precisely the same in bot^ f ases»
aes ifl ahowa by the experioaent of a prism partisdly covered^
wbieb we have mentioaed in our former remarks. Dr. Herschei
ikes not profess b9 have memurtd any angles : he has ookdatttd
soBM angles, upon suppositions, a3 we conceive, wholy erromot^;
itis not thmfore surpriaiiig that then should differ from the true
angles^ ^ 52. Because a second prism is noi necessary for the pro*
duetionof the ^Newtonian red bow. {t is very true, that for the
more convcmeat explanation, of the i^henpoienot]) Newton had
added a second prism in an inverted positioa, in order that the
mmt rays which are subtracted from the white light ia the first
instanee, may be seen alone in the eecond : but the combiaatiop
o£ the prisms is by no meaas essential to tface eshibitum of ih%
bow, which is performed by the second prism olone as completely
as by both together. 3, 4. Bi^raHse in the assertion, that the
iiowa are compkineatary to each other, ^t is not understood that
they are formed'/by eontiguoaa portions of the $ame incid^ lights
jia Dr. Hexschel seems to suppose : the true sense in wbicl^ the
josertion is, advanced, is this; that when we look at the interior
surface of ,a prism in cpea day-light, it appears wtx<^y illanu«»
nated, partly by reflected^ and partly by trausmitted light ; that
if we cover the surface in question, so as to intercept the trans-
mitted light, its remoter portion only will appear bright, and tet^
minated by a blue bow : but if we cover the surface which admits
the rdboted light only, the nearer portion only of the first surface
will be bright, and will be terminated by a red bow ; and parts of
these bows may be exhibited at once, in the maniter wbieb we
have already mentioned, the light arriving at each by a di&rent
path* It is not preten^d here that a portion of the same light
which forms the blue bow can be transmitted so as to form a red
4uus: but that the same line is the common limit of the refiectioiv
which in the one instance forms the blue bow, and of the traiia-
missioa which fimns the ttA bow in the other} and tbis.bein|;
evFPL.— VOL. Ti. 3r
470 Om Coloured Canaiiirk tUngitdwemObfM'GtasiCB, ifc*
true for lig^t of erery ipcf iet or c^loar, the one bow it calM
with the greatest propriety the gtipplement of the ether.
*
Sec. 5 J.— ^ Ittmtraium of the Dependance of ihe Streaks of both
the BotvSf iipon the critical SeparatkmJ'
^ It may be thought by some,'^ says Dr. Herschel, ** that
stress paiallel to' the bows, though not dependant on critical
separation, will in that situation be seen most eiasily,. and most
- distinctly, because the visual ray in that position passes most
obliquely through the stratum of air between the surfaces.*' See
our remarks, p, 410, 41 1, vol v. In answer to this objection, he
observes, ** that these streaks can not only be most ' easily
seen in the place where the bows are, but can absolutely
not be seen any where else/' 1. If the streaks wdid not depend-on
the critical separation, why should they be parallel to the bows ?
Why should they not^ for instance, be in a transverse direction,. as
they might be consistently with the condition o( their appearance
** where the visual ray passes most obliquely through the stratum
' of air?*' The same cause which determinea the direction of the
bow, must ^also determine that of it streaks, and this eUablishes
' their dependence on airtificial separation. 2.'An uniformly thin^
plate of air,, between two plain surfaces, ought not to produce
streaks, so that the very existence of streaks already proves the
action of some principle that will produce different colours/'
3, The colours of the streaki depend on those of the. bows, and
may be changed together with them, by changing the direction
of the light admitted.
Observatuais,-^ Wthough Dr. Herschel here asserts, that the
streaks can absolutely be seen no where else but in the place of
the bow^, yet the very title of his 60tb section stands thus-:
*^ of the breadth of the streaks compared to that of the bows,
^and the cause why they must take up a hroader space than the bom
from which they are derived.'' The truth is that when the sur-
faces are small and well formed, so as to approach very nearly to
perfect contact, thf^re is no limit to the space in which the streaks
appear: in otlier cases, they twill only be seen in or near the
-place of the bow, because it is there only that the obliquity will
be sufficient to produce the effect of a very pear approach to con-
tacts and, first, the obliquity being equal at equal distances- from
the bow, all the successive stripes must of course be parallel to
the bow, in the.same manner as they would be parallel to any
line of actual contact, that for io^-tance if the circumierence of a
convex lens in contact with a concave lens trf a curvature' some*
what greater, as may sometimes be actually observed in achroma»
tic object glassas. 2. A uniform plate zooM no^ produce streaks.
On Cdowred Coneenirh Umgtiei'wem Objtx^ 6Umt$^ fyr.\ 47t
If it w«re placed at tuch adistftnce-that the rays pasfting from it:
ta the eye might be contidered at parallel : bat ihe effect of a dif*
Jkrence of obliquitjf in << the visual ray/' is precisely the same as
that of a difference of thickness. S. The colours of the streaks
can only he those of the light passing from the surfaces concerned
te the eye : in this circumstance there is nothing paradoxicaL
Sec. S6.^^IUuttratvm of tlu dependence of rmgs, seen in a prum^
iipan tke critical eeparationm
A prism being placed on a convex glass, it may be observed
that the rings which appear round ihe point of contact, assume
the colour of either bow which is made to appear at the same part
of the surfaces. '* If it should now be alleged, that streaks or
rings may still be independent of critical separation, because
they must necessarily appear blue, red, or green, when they ara
seen in rays of the colours, we may answer thie otfjectttm^
by proving exprimentally, that any adventitious C'>toors" can
only tipge the rings, but *' can themselves not produce eithef
streaks or rings." For example, when we cause the place of thtf
rings to coincide with the appearance of the celoured light ter«
minatiug a part of the window, as seen through a pribm, the
rings or streaks are tinged, but the coloured fringe bordering the
window is not divided into streaks as it ought to bi9, if thesii ^* ad*
Ventitious colours could diffuse themselves.''
Observations. — We can only say o( this experiment that it ap-
pears to u& completely to^prove what it is intended to disprove;
that is, that any cause determining the colour of the light \^
which the rings are seen, must necessarily determine their colour.
We should be curious to see how Dr, Herschel would atteiript to
demonstrate, that the principle of easy transmission and easy
reflection, or indeed any^otber principle, would lead us to expect
the coloured fringe bordering the window to be divided into
streaks !
Sec.-^SZ*— **BcOTar^* on Colours supposed to be produced by tMn
Plates or ff edges of Air.
. 1 . If it should be objected that irregular streaks, or flashy ap-
pearances may be seen when two surfaces of glass supposed to be
plane are in contact, it is to be inferred, not that plane surfaces
can produce them, but that the surfaces employed are not truly
plane. 2. If it be conceived that strait bands of colour would be
produced between plane surfaces slightly inclined, the objection
is said to be unfounded; for when the straight end of one sll'p was
made to rest on the surface of another, and at the opposite end a
single thread of a silkworm only was placed between them, no.
•tr«iks were ▼isible ootil tbe line of eontact was tlfOB|^y prmiii
together : '* but they were disfigured by pretMMre, and mott dio*
figured where'' Dr. Herschel preseed most. 3. ^ Possibly tmm
plates of glass, supposed to be plane^ may be ahown, wbidi^whaa
pot toget^r slightly inclioed, as t!he exparimtnt reqaires, witt
produce stre^is near the line <^f contact; bat, if thisiidio^b*
the case,''— —it would not be philosophical to ascribe them to
plane soriaces, wheii it has been shown ( that Vylindricalcortes^f
any figure, will invariably produce them ;" for which reason Dr.
Herschel would tbhitiK himself justified '' in concluding, that ona
or other of the platen, which were supposed to be plane^ hid a
oylindrical termination*'^ ^ *
•mmmmmmmmmmmm
0bser9ti$km$*'^l • We gruit Goost willingly that irregular streaks
indicate an irregular and not a plane surface. 2. The streaks
tiaving been disfigured by pressure, and most disfigured where the
pressure was greatest, it only follows that the irregularity of the
atr^aks^ not their existence, depended on the change of fonn
which thn presaure produced : and wh^i the streaks are not irre*
l^lar, but parallel and equidistant, it follows of necessity from the
observations of Newton, that if one surface is plane the other
Kust be plane also. 3. We do not know in what school of pk£^
iophy it would be asserted, that because cylindrical surfaces will
produce streaks, it follows that such surfaces ^/y can produce
them : in fact the distances of the streaks, as we have already
observed, will always serve to distinguish the effect of a plane
iirom a curved surface : but these are minutiae too insignificant to
attract our authof's nolipe*
^ect« 5Zj^* liluitratwg Remarh on (he mtention of the iJithJfgurt,
esplainedm the 4Sth Article of my Paper/'
It appears to have been objected to this diagram that the va«
cancies supposed to represent those of the streaks are observed tq
correspond with' those which have been originally assumed as
intervals between the rays of light : but first, some of the vacan-
cies do not correspond. 2. 7'he rays are not assumed as jseparate^
by blank intervals . i. The figure yfas only intended to denote the
f^ incipient course" of the rays in posing to the eye : *{ to m^ke
a calculation of the mixture and colors of all the rays when they
reach the eye,*.would be l^tremelv Uborlous, ancl~a thorougli
investigatioD of this particular point would reatly---be an endless
undertaking :*' 4. we have the authority of Newton for represent-
ing the affections of aiiy pencil of light by delineating, the course
of soi^e fewof the rays ouly.
Observati9ns*-^The objections mentioned in this section npt
being such as we have actually made, we do not think it necessary
(hi€9kmiCe9cmimMmg§Ukm$0I^Camu^tf^ UTS
im enlbrec tbcm btra : •iptdftlly m, if w^ aUowM tJuiA Dr«
Htnchel had combatad thtfoi with some succew^ wt tbould still
leDMin of opinion that this complicated figura demonatratea
noihiDgandilkutratea nethiBg. A *^ thorough mveatigation** oC
the point» which aatine to Dr. HerschaU an e^dieaa undertakinif
vit cannot help thinking ahaolotdy essential to the f oaclasioa
which is to be dedaced : and what the result of such an investiga^
tion wonid be, we have not the slightest difficulty in inutg^iiag.
Sec. 59^—'^ Experimentt tm the rndttpb/tng Pofwer of Swfacet m
coniadf whkh mod^y ike form 4fjniimatic appeanmciiJ'
A prism being f^laced on a plane metalic specnlnaa, in a posi-
tion somewhat incUned* a number of imagea of a luminous object
are formed by repeated reflections'between the base of the prism
and the specdum.
06«erva/ioff«.— -We have no objection to the experiment men*
tioned in this section ; to say that they are merely superfluous, is
comparatively an eulogium.
I
Sec. 60.-^^' Of the Brtadth of the streaks camftared to that qfthe
BowSf and the Came why they must take vp a broader space than
the Bows from whkh they are dtrived*
On Uss subject of this section we had Yemarked, p. 412, vol. t^
that '* Dr. Herschri seems to be fully aware that a critical separa*
tion'^ tiAes place only at a certain atigUy that is, in glass^ about
30 degrees ; he has himself confessedly seen that the coloured
]*in^s are Tietble ut atl 4mgle9, aud yet he has the inconceivable
faculty of satifying himsufy that the critical separation is the
genepal cause of tibese colours ! To explain, therefore^ why tt)£
streaks ^*take up a broader space than the bows," Dr. Herscbet
has recourse to repeated reilections between the surfaces con.
eemed. 1. A single reflection, which might be delineated in th€
figure already mentioned, would increase the breadib of the bow
about one ninth. 2. By inserting rays in different parts of the
figure, we may give an extent to the streaks greater than that of
the bow, in the ratio of 2^ to l. 8. By a repetition of six 01-
ftight successive reflections, we may enlarge the breadth of the
streaks to any lequired extent. «^ *
Okacrvatums.'^To this very imperfect attempt, to give a very
partial' solution of an insuperable difiiculty, we have only to re*
ply, that any reiteration of successive reflections would necessa-
rily produce a crowd of images of each streak, which would com-
pletely flil up the spaces between the streaks, so as to create an
universal confusion -, and that the nonexistence bf such repeated
474 On Cohurtd dmcentrk Rmgi hHwem Object (Srlasscs, 8t€\
refiectiofis is thown, by causing th^ Image of an opaque object
Ui fall on the spot concerned, when the colours only disappear
precisel}^in the place of the image, and not beyond it, as they
should do if tliere were a further refusion. And if we even
granted the sufficiency •f the explanation, it could only be appli-
cable to the very few cases in which the original angle of iftci-
dence happened to be about SOP \ leaving all the more usual cir-
cumstances of the experiment still unintelligible.
61. Of the manner iit which Rays that are separated by critical
Reflection or Intromission come to the eye.
In this section Dr. Herschel informs us, that " by means of the
principle of the intromissive separation of the colours,^ he has
** already accounted for several appearances, that no other prin-
ciple, not even the >f^wtonian fits of easy reflection and easy
transmission, can possibly reach ;" and he proceeds to anticipate
the objection, that rings may be seen at the under surface of a
glass terminated by parallel planes, '^ and in other situations in
which .critical separation cannot reach the eye." (sec p. 41 2 of our
5th volume.") He observes, that he does not assert the critical
separation to be the sole cause of the rings, but merely to furnish
the colours, which are afterwards variously modified by the sub-
jacent reflecting surface. He next adduces a set Of experiments
made with prislns of different forms, placed on a convex metalline
mirror, which shew that the rings may be rendered visible under
these circumstances^ in almost all elevations of the eye : and a
second set of similar experiments, in which jthe prisms were placed
^on cylindrical pieces of glass and metal : a piece of mica was also
'bent into a cylindrical form, and produced a similar effect. These
three sets of experiments prove, in Dr. Herschell's opinion, that
the first of the assertions, into which he has ^* divided the objec-
tion, is not well founded f that is, ^' that in. the situation of a
plain glass laid upon a convex surface, no critical separation can
reaph the eye."' This is disproved, as he thinks, by4lie experi-
;nents, " because the modification of the subjacent reflecting sur-
jface, so essential to ^the formation of the phenomena under con-
sideration, has not been attended to." With respect to the second
form of the objection, *.'garding the ncccfssity of either showing
the possibility of the arrival of the rays of the critical Separation
at the place of the eye, or of attributing the appearance of the
rings to some other cause, it is sufficient to have proved that the
rings iEire formed from the colours of the critical separation, and
that the field of visibility may be increased by" the modification
of reflection or radiation." ". It has been proved by experiment,
da Coltmni Cancmtrk Rings between Ohfect &huseiy ipc* V[i
that a diminution of the prismatic angle aviU gradually extend
the visibility of the rings, till — they may be seen in every direc-
tion ;'' whence '^4t .ift- evident, that an objection,, ^which asserts
that such colours cannot be seen, contradicts the plainest and
best established facts." '^ With respect to the actual course of
the rays," he observes, it cannot surely be expected that ht
^* shouM-trace them through a most intricate complication of
reflections frohi ■ curve to curve, when it has been shown, — that
'even with streaks, which are produced by the Contact of two
plaiii sbifaces, it would bean'endless undertaking to follow them
dll they enter the eye."
f)h9erGutiws,-^\\, is manifest that none Of thesfe remarks are in
any degree applicable to the case, which continually occurs in
the production of these colours, where none of the light con-
■ -^pemed^has passed atany time through the glass in an angle at all
' approaching tb 50**. When Dr. Herschel asserts, that his experi-
. mcnts dispicove the iirst part of the objection, he seems wholly to
have forgoj^ten what the objection was. It was objected, not that
the m^ Qf^cQlQ%r% could nptbeseen at all angles, but that the
li'^ht subjected to the '' criticaLseparatian'* could not be seen at all
angles : ai)^ jn the same manner with respect to the second part;
wh^e he sj[)eaks of an objectioii as asserting that such colours
^canmthe seen,, he appears to have been guilty of a similar inad-
Teftency,. since the objection is solely grounded on the assertion
that the colours, c<i», lie seen in all directions ; which they could
not possibly h^ve been, if the critical separation, so much cele-
brated .by Dr. yerschelli were^in any iiianner concerned in their
production; -
We should apologize for the.apparent prolixity of this article,
jf we were not coi'iscious tluit very few of our readers will be ma-
terial sufferers by it, and that its length is very inconsiderable
when compared with the number of pages t\h rough which we
have deemed it our indispensable duty to follow our author. We
most sincerely hope that he will aflFord us an early opportunity
of attending him in some of his excursions into those fields of
science, in the cultivation of which his labours have heretofore
been rewarded by the most brilliant success; and that he will
lea vie these more thorny paths to be trodden by humbler and lest
aspiring adventurers.
I"'
I,
'l
( 4»« %
* 1
ad Obigrcatumi; im a Letter from S. Gaoombaxdgs, Ea^, fo
ti£ SUn* Nevil Masxislynk^ D.D. F.R.S, Astromm^r
Bio^y — CwmummJtei bjf the Jstronomer S/tjual* FAU* Tr^m.
PartIL 18ie.
t* Extract of a Letter from the Bet. Jowa B&ivjclet^ D. D.
F, R. 5. Andrew^ Professor of Astronomy in the University of
lOvki&n^ to the Rev, Nfivit. MaskeltKe, D^D. 1*. Jft.o.
MtrQnomer Royals on the ammal Pandlax of^ Lyrm. IM.
' S« A sfiart account if ike Improvemcuts gradually made in determtn"
ifig theAstromomtcul Refraction. Bij T. $.£taif8« — PhU^Mtig,
' NosA5land:l5t.
]• Mr. Groombf idge heviiig -undertaJ^^ a series of astronomi-
tH observations, for the purpose of ascertaimhg the true latitude
of his obseri^tory, and endeavouriftg Co determine tbi5 true qu^U"
ttty <rf refraction, he fixed upon 5G<:ircum polar stars, of dsiterent
altitudes, on which he made more than IWO obserratrohs. As-
tronomers have net agreed upon the quantity of refractton to be
assumed at 45*. Dr. Bradley s'apposed the sun's parallax to be
l-OJ.^', and- inferred from that supposition, that the refraction at
4i5^\ira5 57^; but Dr. Maskelyae had remarked, that if the true
parallax of 8|« had been taken, the refraction thence deduced
vrould have been 56 J^'. Mr. G. therefore, adapted this last re-
fraction, which he c6rrected for the barometer and thermometer-
' and made use of the formula of Dr. Bradley. He 'has arranged
his results in a table; the iirst column of which contains the
stars ; the second the number of observations upon each ; the
third Ae mean of the observed zenith distances, corrected by the
equations, to the first of January^ 1 807. The fourth column is
the mean of the computed refraction ; *' the sixth is t!he sum of
the third and fourth columns, which gives the mean double zenith
distance of the pole, accortiing to the assumed refraction in tbe
seventh column ; the eighth is the correction of the assumed re-
fraction by the factor found •02845, which is applied to the
seventh column, and gives the true double zenith distance pf the
pole in the ninth, the half of which is the corrected co-latitude
in the tenth column.'' The fifth column is occupied with thetum
or difference of the numbers in the fourth.
The sum or difference in the seventh column being sufficiently
uniform to be used in correcting the refraction, Mr, Groombridgc
^ Ob^rvations on atmdipherical Refraction^ (J-c. 477,^
comparos the first thirteen stars, the zenith distance of which be*
low the pole is less > than 60^ with the twent3'*o&c follawiRi;.
*^ From the former thirteen, the mean of the seventh column is,
77«> 5^ 53^^^, 09O8 ; and the mean sum of the refractions in the
fifth column is 9V\ 9577 i from the latter twenty-one the means
of the same columns aire 77° 3' 50^^ 5248 and 185'''', 1357.
The difference of the polar distances, divided by the diflferencc of
the sMtm of the refractions, quotes ,0284485 ; which being in-
creased by unity, is the factor to be multiplied into the assumed
refraction, vii. 66} ". Then the mean refraction at 45^ will be
56i"x 1 , 02 845 =58 '\ 10734; the co-latitude
77** 3' 53", 0008-1-0419377 X, 02845
— > ^^y^oT-y*>y^f i .^ s:38o 31^ 57^^897 j
and the latitude ••••• •••s:51 28 2,103;
which will be found the same from the mean of the corrected
co-latitudrs in the tenth column, as given by the above thirty-
Ibyr stais."
From eighteen observations of the sun at the sum^ierf and thir*
teenst the winter solstice, Mr. G. makes the latitude 51o2S'
fi''S5 ; and the mean obiiqfuity of the ecliptic for the same period
«3^ 27^5S",()7. The nejv §olar tables state this obliquity for
a 800 at 23^ 27' 57" ; and if the atipual decreiise be estimated at
lukl/a seeend^ the above result will be very near the trinth.
Mr. G, then compares the observations of other astronomers^
and obtaiiis t^esults nearly equ^ to thctse ailready given. He also
remarks, that £^. Bradley^s fornmla fails for low altitudes ; and
then prroc«eds to tnvetttd^ its correction, aad gives the following
resuh.-^^^^ Having thus assuined a greater value of ^ than 3, foi* the
co-efficient of r, lAie mean refraction at 45° will vary inversely, a$
tang, z— 3r ; 58", 10734 :: tang.;8— j^r ; x; therefore,
tang. 45*'-3rxj8,l 0734 . ' , - . '
«3: — 1. ^ ' , ■■■?:5B", 1192/'
tang.45o— ijfr
This writer then investigates equations for the barometer and
thermometer. On this subject he obseryee, ^* Having determined
the mean place of the star at a certain epoch, I find the apparent
plrice', the difB^renre between which tod the observed place, is the
apparent refraction, whichcaUa; put ^z: niean refraction, cirs
the correction for the barometer, and w=: the correction for
41-5
the thermometer : then — : — -^c=w." After illustrating this by
an example, be again observes — " Putting h for the degree of
Fahrenheit's therjnometer, then 49o—^ox-0024, when below th^
6UPPL. — v;)i.. Y. 3 Q
478 Observations on atmospherical Refraction^ S^cJ
mean; 49®— /iPX'0023, when above the mean, will be the cor-.
» ■
re'ction for the thermometer within; and 45o— ^o>C'0021, th©
correction for the thermometer without/' Thp mean without isr
taken at 45**, and that within at 49**.
He then explains four tables which he has subjoined to bis
essay. Xbc first of those contains factors for the correction of the
refraction, the mean result of 210 observations ; and for the ther-
mcJTiiOt'^r both within and without; the second and third are fac-
tors ocuatcd from the moan of the above'; and the fourth consists
of l\-)c- mean astronomical rcfi'actions, rcc )i*dine to several-
authors,
2. Ti-bm 22 observations en Lyra^ ncai- opposition, and 25
iicar conjunction," Mr. "Bnnkky mi^kcs ihe aiinual parallax of
tliat star 2", 52 ; and adds, " l^Iy obr,crvatiflns of different cir-
cumpolar stais, ai^d o^ tl e same' star in. diticreiit states of the
thermometer, seem to n ••iiire a small alteration in the numbers
of t) I*. Bradley's forfnufa. for refraction.^ "J'he! formula so altered is
C 1 -HeijjUt of barom. ' 500
1lefr;=56' ', 9 X tang. 4 Zeh, dis. - 3,2 Refr. > X — ^-:-^ X -r
( ) ' 2P,6* . 450 -f. therm,
• !6y means of this formula the observations of circunkpolar stars
considerably distant, givethe same co-latitude to a great degi^ee
of exactness.'' • . > ,
' 3. In this third part, after some general observations relative
to the importance of refraction, the uncertainty respecting its
quantity in low altitudes, and the difficulty of ascertaining it,
Mr. E. remarks, that Ptolomy has observed:, Jn the 8th book of
his Almagest,, that there are changes in the rising and setting of
the heavenly bodies, which depend upon the atmosphere. Alha-
zen, an Arabian author, who' wrote about "the year 1100, also
speaks of refraction, and shews the manner of proving it by expe-
riment ; but he does not appear to have asccriained its quantity.
Willebrord Snell published, in the yeaT*l6l8, a collection of
o1)scpvat ions made by Bernard Walter, in which it is stated, that
these wore so correct ^s to shew the quantity by whicii the alti?-
tudcs.of the stars was increased by means of refractionf ■
Tycho Brahe, however, is regarded as the first whoas^sertcd
that refraction elevates the heavenly bodies rather more tha^i half
adcgivewhen they are in the horizon. He supposed the refrac-
tion of the sun when in the horizon to be 34', and that it became
nothing at an altitude of 45". That of the starfe in the horizon he
made 30', which also vanished at 20'' pf altitude.. Tycho gave
tables of the refractions j and that for the stars is copied by
•Mr. E.
Observations on atmospherical Refraction, ^c. 479
. Several years elapsed before any, further improvement of consc-
queiice was made in refraction ; for Riccioli, in l665, supposed
k to vanish at. 26^. of altifudel He also stated that of the moon
at only 29^, when in the horiison, in summer ; the sua 30^; and
the stars $& 37^^.
The elder Cjassini, subsequent to l672, took the subject into
consideration, and published a corrected table, which was the
first that had been computed for all degrees up to the zenith. He
also supposed, that near the equator the horizontal refraction was
about one-third less ^ than in our climajte; and that this dif-
ference diminished as far as 60^, when it bcca^nc the same' for
both climates.
In 169^, the king of Sweden observed, that the sun did not set
atTornea, in latitude 65° 45^, at the summer solstice; and he
sent mathematicians in the following year, to make observations
on this subject : from thesis M%srs. Cassini and De fa Hire con-
cluded, that the horizontal refraction in lat. 65° 45' must be 5S^*
or nearly double of what it was at Paris. It was also observed by
some Dutchmen who passed the winter of I696-7 at Nova Zena-
bla, in latitude 76% that the sun rose six days sooner than was
expected from astronomical calculations.
Newton calculated arable of refraction from theory, which
was published by Dr.Halley in t^c Phil. Trans, for 1721, in
which he made the horizon^l refraction 33 ^ 4k5^^.
. Mr. Flamsteed also published, in 1725, a tabic computed
from his own observations^ iu which he assigned 33 'for the re-
fraction in the horizon.
The law of increase from the zenith to the horizon now became
»n object of inquiry, and occupied many of the principle mathe^-
maticiansaud astronomers for more than a century ; and Mr. £.
has enumerated twenty-two of those who have been distinguished
ifi this investigation.
Messrs. Lowthropc and Ilauksbec were the first who introduced
corrections on account of the variations ofthe atmosphere, as in-
dicated by the. barometer. The former of these gentlemen proved
before the Royal Society, in 1698, that the refractive power of
the air is directly proportional to its density ; and the latter, in.
17O8, found from experiments, that the variations of refraction
depending on the barometer are proportional to the height of the
mercury in the tube ; and he calculated a table of the corrections
necessary to be made for the changes in temperature, as indicated
by the thermometer. The quantity of refraction was found by
experiment to be different in different parts of the earth, and also
at different altitudes above the level of the sea ; and the tables on
the subject did not agree with each other. Fla^isteed made th^
4Sd Obser'Oations on atmospherical "Refract ion^ SjfC.
refraction tit ^n aUitucIc of 30** equal to I ' 23 "j Newton, 1 '30'';
CassinJ, 1 ' 42 ' '; and Pc la Hire I ^ 55 ''.
La Caille published a tnemoir on the subject am^^tig thoie of
tfee Academy of Sciences, in which he compared the ohsefvationi
mad? in different parts of Europe, and gave tables of its q*4an*
tity. He m^K^s tjifj refraction at 45^ equal to 66} ^^
About the same tinie Euler published a formula in the Memoinr
of the Berlin Academy ; bi}t which appears 'to h^ve been to^
complicated for general adoption.
. Pr. Bradley was the next who made any considerable improve-
ments in this branch of physical' science. ** The rule which he
adopted^ although ^ very elegant one, he neither lived to com*
plete, nor to present to the world ; but it was published after bis
death by Dr. Maskclyne, and has commonly been used in Eng-
land up to the present time, f^ found the mean refraction at
4.5^ of altitude 5/ 'S and that at ail other altitudes it was e^ual to
57 '' multiplied by the tangent of the 2enttb distance, diminished
by three times the refraction. Then, supposing the mean state
of the atmosphere to be at 29.6 in. of the baron^eter, and 50® of
t ahrcnheit's thermometer, he i^adc the true or corrected refrac-
tion equal tp
barom, 400
57'>+f (Z.D.-5r)+ X-^ . where it is to be
29.6 350+ therm.'
understood that the mass of air is supposed to increase in bulk
"ijhr ^^f every degree of Fahrenheit's scale."
Mr. £. next states the results of a number of expcnm^tta that
have been made by various authorttodeteimino the increase in
bulk of a quantity of air, corresfiondtBg to a certain vise of the
thermometer. He then gives an abridgment of a chapter on this,
subject contained in LBiip\Bm^$ Miotmiqne Celutef publishedf in
1 805. pelambre has reduced Laplace's theorems to a i^ore con-
-venient form^ and computed a set of tables by which the refraction
may be found with great facility. These tables were pi^lishcd at
the end of Puissant's Traite de Gcodcsie, in 1805.
Mr. E. thon gives an accoi\nt of the paper whfch constitutes
the iii>t part olf tl^is article, and propose^ sonie alteration in Mr*
Groombridge's eriuations for the thermometer, for avoiding tke two
numbers 49 and 45, by reckoning the state of this instrufi^Jit
from Zero : but for these we must roter to the paper itself. . He
also states, that Mr. Groenibridgo ^' has calculated o^ithe data
above mentioned a table of reflation for every 10' dowi^ to
70° of zenith di^tan^e ; for every 5' from thence to 86^ ; for each
4' thence to 8H"; each 3' thence to 89**; and .for every S^from
'thence to 90^* 18' ; together with an auxiliary table for the cor«
rcction dfpcndiug on the diffci'ence of the barometer and thermo-
Ob^ervatidni $n aimotjAffkal Rtfrotilon^ i^tl i$%
mHer from the mean state. He has also eontnTcd soihe vcrf
sifhple methods of performing, with great fkciiity, what<jver mritk^
itietie operations may be necessary in using them/' Mr. FA-miif
t}^en concludes with ifae felVowing ruU; for finding the sun's iiaraW
lax. /*' Add iogetiter tAt legaritkmie sine af'tAewuVzeaiH distoMor^
the logarithm dktmeefhr the given day\ iak^nfrum page iii. Nosh
Heat Aim€maeky MHd the c4^nUaRi number 0.94151 :. their tnm^ re*
jecting the tens in the ii^d^x^ will te tlw (oginritAm of ifh^ ^s*|
paraUax in seconds!*
ObientKtlont^ — Mr. Groombridgc is known (o the public as aa
ingenious astronomer ; and both the number of tlu*se obsen.'ar
tions, and the accuracy with which they appear to have bcea
made, render the results both «alisfoctory and useful, and
the paper highly welcome to the practical asti'onomer. Tfaie
instrument with which these interesting resoits were obtained,
is a four feet transit circle, lately constructed by Trougikr
ton; respecting which Mr. G. in his introductory remarks^
observes, '* My instrument was* better adapted for- that pur--
pose, both from the construction and ccmvcnient size theiteo^
Xhan those which had been heretofore used. Being fixed on stone
piers, it is not so liable to partial expansion, as those instruments
which arc supported on brass frames ; and hating both sides
divided, with two microscopes to each face, the same observation
has the advantage of four made with a quadrant." ^ It should
be rcmadved, however, that iu Mr. G.'s correction for the ther-
mometer, when the state ef that instrument is above thesttcan,
^he numBer^ and not the A^, should be negative. We u&doirclj
^ope, that the tables of nefiraction which Mr. G. has siufie txm-
puted, and the "methods of calculation he has devised, will form
the subject of another eafly communication to the pu)»lic, and
prove highly service^le in promoting th« science*
Mr. Evans has brought together all the principle attempts that
have been made towards ascertaining the quantity of astronomical
refraction ; and by reierences to the originals, he has pointed out
to the curious reader the sources whence he may cu>taia mom
acmple gratification. He has also taken occasion to lament ^ the
deplorable state of astronomy** in this kingdom, and the small
' degree of cultivation which it at present receives ; but we taa
assure him, that eren now he might have found morp than ^ half
a dozen persons'' who have written on the subject, and who nust
therefore be classed among its cultivators.
We cannot forbear noticing here the partiality which ao^
*pf aetlcal astrohctfuers hiive o^n ^ewn to inaccurate appi^oxim^
tioiis in preference to i^orrect formulie, even wh4^ it would ^
easier to employ the perfect than the imperfect determinatioiiL
4St Ob$erOaiiWM on atmospherical Refraction^ S^c*
Tknsy in the present instance, the formula which Simpson first
laid down for the calculation of the atmospheric refraction, is at
the same time more direct and shorter than the awkward approxi-
mation of Bradley, in which the quantity required is supposed to
be already ascertained.. And in the same manner wc may find the
refraction according to Dr. Brinkley's observations, by subtract-
ing .OOO768O from the logarithmic sine of the zenith distance^
1
and taking —" of the difference of the corresponding angle and
the zenith distance. Thus, at 45^
Log.sin.Z.D. =: 9.8494850 8)364"
Subtract- .OOO768O — — ' .
.8) 45.5
Log. sin. 44^ 53 '56" 9.8487170
Agatm, at the horizon
Log. sin. 90** ' = 10.0000000
Subtract • • • • .0007680
56.9
Log. sin 860 35 '37" = 9-9992320
Difference • • • . 3«> 24'23''
-8)12263"
.8) 1532.9
1916.1 =1.31' 56/'. I
Mr. Groombridgc's formula, transformed in a similar manner^
elves 6.725 for a divisor : and wc may take for a convenient mean
oj, or .15 for a multiplier; which, in order to give 58" at 45**
will require .0008150 for a subtrahend : for 57% .0008015.
For example :
Log. sin. 90» = 10.0000000
Subtract... .0008156
Log. sin. %&" 29' 23" = 9.9991«4»4
Difference.. 5^ 301 37"
=12637"
6318
I895.5 = 31' 35.5"
Mr. Groombridge's table gives 31' 27-9" ;► but it is doubtful
trhether observations have ever made the horizontal refraction
less than 32'; and whether the divisor can properly be tak«B
greater-titan 6.5 at the utmost.
( 483 ) •.
Sifmt particulars respecting tht Thunder Storm at London, end tii
* .its P^idnky, on the ^\st of August , 1810. By SirH, C, Ekgle*
riELD, . Bart. F. IL S. and K S. A,— Phil. Mag. No. 151.
As the stroke of thimder here refeitcd to was> perhaps^ th«
mo^t violent and awful ever experienced in tbis country^'and thtt
Icarfied baronet ati eye witness near the spot where the principal m»*
chief was done, he conceived' that some account of it w^ould not b«
unacceptable to the'public ; and therefore has drawn up the follow-
ing particulars. He was, about half past two in the morning, with
three other friends in a coach, standing within the light of alarg«
lustre and two bright lamps ; which he confiders'as favourable fot
seeing the nature of the lightning distinctly. A small mizzling
rain fell, and as they stepped into the coach, a very strong flash
.of distant lightnino; appeared in the North-east, but no thunder
was heard, l^ere also had been much distant lightning for an hour
or two before. What followed is thus described*
** The sky over head appeared ' verj- dark,* but the lights pre-
vented accurate observation of it. We wer« just seated in th«
carriage, and my eyes -were directed out of the front window nearly
towards the tree which was struck; but^hich ho^vever I could
not see. Two of my companions were looking out of the window
towards the house door, from which we- were distant five or six
ieot. We were at once enveloped by an excessively bright diffused
blue light of more then instantaneous duration, which appeared
to explode into sparks moving in zigzag lines m all directions.
My friends saw them between the carriage and the door, and theit
motion was so strong as to make the pillars of the porch appear
to vibrate. The whole had very much the effect of what, in artifi-
cial lire-works, is calif d a balloon, which, as it bursts, throws out»
from its luminous centre, squibs in all direfctions, Simultaneout
with these zigzag sparks, an astonishingly loud, heavy and singlt
^explosion took place, similar in sound to the discharge of all
enormous cannon directly at us, but incomparably more violent.
The explosion seemed quite on the ground, and was accompanied
t)y a sensation of a dull concussion, as if a vast weight had fallen
from a gre^t height on the soft earth close by us. The sound rote
in the air, rolling and echoing for a very long time, much lika
cannon thunder."
• I'he servants of the house where these gentlemen were dcscribal
the stroke ^s appearing to crush the whole building. j\ heavy rain
succeeded ; and the ccntinel at the gate leading from Kensington to
the palace, was so dazzled and stunned that he could not give
f uy distinct account of what h&d passed ; but it seemed as tbouj^li
I«
4M Thttndo''Storm at London and tn it* Vicinity.
a vast cannon had been iired at him. Another carriage had just
Iffc the dtior wkcTc these gentlemen were, and waJ perhaps still
- nearer the tree that was struck. ^* The horses stopped short, and
Remained motionless^ the gentleman in the carnage, when he re^
covered from his surprise^ spoke to his coachman, who, as well as
the footman^ declared themselves stunned and blinded. After a
l^Bseof a few minutes tliey however recovcredf and felt no further
ill ^fhcnJ* Theeentincl at the Duke of Sussex's door was knocked
^wn by the shock, dud |-ematned -senseless for a short time.
On hearing that damage had been done at Kensington palace^
Sir Henry went to view the spot, and the effects being singular^ we
«haU tratMcribe his brief didcription^ ^^ A large elm in the outer
pttlate-Jrard, near the guard-house, and about 120 yards from
ihcspoi whel« o^r carriage stood, was struck in a manner rather
teCoAason* A maijt root, about the size of a mans thigh, wusi
k^QWa out of the ground to the length of twelve feet from the trunk
nf the tree, and was broken ilito three pieces. Tl>e trunk of the tree
9ra» barked at iatervals, not iii a continued lino, and thh injury
quitted the stem at the lowest large branch, and followed that
jiiffanGli il|^ to a fbrk where son^ decay appeared ia the wood.
Beyond tbat^ no Injary ap];K^arcd^ nor was the main stem or any
^ber braUeh^fliectcKl. The whdle appearance of the tree». as well aa
fbcsensat^fttlfeUfromthd explosion, lead me to' think that th^
abock was fion^ tkee^ifth to the passing cloud, the part of the pa-
la^ directly opposite to the tree i» a long building with large arched
wiadows: in theae4S panes of glaas were broken by the concussion*
Tlips building is about SO yards from the tree."
Two of the gentlemen of tb)9<{>arty had often visited the southern
parts of Europe and ttie Moditertaae^n, where thupdcr is more
violcttf than in England, but ^ey h^ never witnessed any thing
like ibis. In London tltc sensation it oceasioiwd t^'sis similar to
.that already stated. The toU-m^ii dt Hyde-Park cofrnorand tl^
watehmeu in the streets described the air 96 eompleteiy on fire ;
|lnd the papers gave ail account af a centiitel having been struck
down near the liotsc-G nards ; which render it highly probable
.d»at the discharge took place in several points at once.
Observations, — We are certainly not acquainted with any thing
kaving taken place in this country, which was at all comparable
iu>this thunder*storm« described by Sir H^nry ; andthiak the nature
€f its effects suflicicnt to induce l^im to suppose that the di!»-
ctorge was from the earth to the clouds } and that thj* explosion
look place at several points at once. For some remarks relative Xp
auDuitanco us discharges, sec page 422 of uutr 5th volumo.
.'( . 485 )
<Jji tit7i€W Mtm^faifi Banmeieri By Sir Hex hy C. EXGLXFi«t d
Bart. F. R. S. afidF. &:A,~PhiL Mag. No. 150. .
The author of this communication states his obj<3Ct in making
it to be two-fold ; viz, to inform the public of someiraprovfcnients in
the construction of the mountain barometer invented by him, and
-to propose some method of coHeeting the observations made by in»-
• Aviduals, ,fpr general benefit.
the improvement in the construction is chiefly in the cister»«f
the barometer. It had often been found that, when exposed fo
violent motion in an unfavourable position, the upper part of tfie
tube was cracked by the agitation of the mercury ; and to remedy
this inconvenience, the cistern is now made with a bottom of leather
against which a screw presses and forces the mercury nearly to tli^
top of the tube, when packed for carriage. When the barometer
is prepared for use, the screw is to be unscrewed as far as it will
admit ; ,a^d then the cistern will be in the same state a& those of
the former construction. This screw is protected from injury by
a cap. It is also stated that the .content of each tube is separately
ascertained, and the correction to .be made to the results, as spe-»
cifif d in his former paper, i$ engraved on the mounting.
The second object is to inform gentlemen who have made obsef^
vations of this kind, with either this or any other good mountaih
-barometer, that Mr. Jones, of Kenton-street, Brunswick-square,
"will receive and arrange such observations for publication either
in the literary journals or a separate work^asmay be forwarded to
(him. A specimen of the form of arranging the observations is also
^dded, and it is remarked that it would be useful to denote the
■soil of the place where these were made, and the temperature of
th« waters in the vicinity; and a well of 40 or 50 feet; deep ik
recommended as most proper for this purpose,
Observations. — Many of our readers will recollet that we desi
*cribed this useful instrument, invented by the learned baronet, ?it
fMige J48 oi our 2d volume ; and gave a further account of his
rules for the determinations of altitudes^ independent of loga-
rithms, at page 12 of our volume 4. As every thing which tends
to render An instrument of this kind more safe or commodious in
the conveyance is desirable, we think the alterations described iA
this paper are improvements. We also hope the plan for collect-
ing and giving publicity to the observatsons made by ingenious
individuals will be successful ; 'as it is by those means only that
they can be rendered of general utility,
RPPP^t — VOL, TI, 3 »
( ^^s )
Hinti respecting a new Theory on the ^Orbits of Comets. Bp JMirr
W. Crane.— PAi^. Mag. m^ 150.
Mr. C. remarks that the difficulties with which this intricate
branch of astronomy is surrounded, have given rise to numerous
theories relative to themotion of comets ; a few of which he briery
men^iop^ befpre be offers his own hints on the subject. The Peripate-
tic? did not assign comets any place in the planetary system, but re-
garded them a^ terrestrial exhalations. Tycho Brahe, and Kepler,,
were the first who showed that comets were at a greater distance from
ti^e earth than the moon : and this was confirmed by Cassini's
observations on those which appeared in 1665 and 168O. From
these he supposed that they moved in very eccentric circles, which
fonjbained the earth's orbit iwithin theqi. He also thought that
they moved through certain constellations which he called the zo-
diac of comets ; but later observations have proved this to be in-
correct. James Bernouille, in his System of Comets, published
in l682, regards them as satellites moving about a primary pla-
,vhichnet, revolves round thesun^butwhich could no'tbeseen on ac-
count of its minuteness and iuimense (listance ; and the comets he
conceives to be visible only when they descend towards us in peri-
.^eum. The periodic time and other circumstances assigned to this
jPlanet, however, were so contrary to what had been observed relative
to planetary motion, chat it was the fame of its author alone that
Supported this theory. Newton, Gregory, Halloy, and others have
supposed them to move in eccentric ellipses, having the sun in one
of the foci; and some have imagined this motion to take place la
,a small part of a parabolic curve having the same vertex and focus ;
>vhich is the true trajectory if the. planet do not return. " This sup-
Jpositiop," Mr. C. observes, "only leads us from one difficulty
to another; for we may next ask, by what means did it come
within the attraction of the sun, and from whence? Are we to Suppose
i)b pass^ from one fixed star«to another in a serpentine direction^ '
whichistbc |;heory adopted by Mr. Cole V* Laplace's opinionis that
jnentioued reli^tiye to the orbits of comets being very eccentric, and
.the sun extremely near that part in which the comet is visiljle to
us. The following inference. is then drawn, " hence is it not pro^
l)able that they revolve about two fixed stars, placed in the two
foci of their orbits T This idea Mr. C. thinks is strengthened by .
the great eccentricity of the cometary orbits ; and that the attrac-
tion of one of these powers ends where the^other begins. This he
fonceivcs will also account for their appearance from different
parts of the heavens ; as ipany may revolve about the same sUx^
Mr, Moore on the penetration of Balk* 48X
but only one about the same two stars. Mr. C. then gives th«
foilovving calculation on this curious subject.
" Ferguson, in his Astronomy, estimates the nearest fixed star
at about 32,000,000,000,000 miles distant from the earth, con-
sequently it is d2,000,082,O00,0<}0 miles from the sun; and Adama
in his AstFonomical Essays> says that the comet seen by Brydon,
at Palermo in 17Z0 moved at the rate of 60,000,000 miles an hour.
Now admitting this lO be the average rate, and that it performed
fi revolution once in 129 years, which is the period assigned"to
that which appeared in lo6l, we shall have ^7,802,400,000,000 '
miles for the length of its orbits ; and it is not improbable that
this would be the perometer of an eccentric ellipse, whose foci
were the distance above mentioned.**
Observatiofis* — Mr. Crane has fallen inUj an error in calculating
the length of the orbit of the comet which appeared in 1770, ia
which he takes the perihelion velocity for the mean velocity of the
tomet. Nor can we consider any part of his discussion as tending
much to elucidate the subject which he is examining. It is per-
ifccily well known that if a comet describe the nearer'half of a verj
eccentric elliptic orbit bymcans of the sun*s attraction, the same
force .will be abundantly sufficient for its describing the remoter
half exactly in the same form, although in a time incomparably
longer, without requiring any attractive body in the other focus :
the, presence of such a body would indeed materially interfere with
the form of the whole orbit ; but if its distance were extremely
great, it would probably not cause the part of the orbit within our
observation to deviate' materially from the parabolic form. The
only calculations relative to' this subject which we recollnct, are
those of Mr. Poisson, who has entered into some investigations of
the motion of a body actuated by the attraction of the earth and
moon, A»hich might be applied to tl^at of a cometsupposed to re-
volve round two fixed stars. An abstract of these calculationf
lias been published in the Bulletin of the Philomathic Society of
Paris, No. 7 1 . But we must again observe, that their application
to the case of a comet must be merely hypothetical, as far as re-
lates to the possibility of ascertaining their coincidence with expe^
Timent ; since our observations could never ascertain' the exi^
tence of any variation from the parabolic form,. which the attr^c
tion of a distant star might, in theory, be shown to occasion.
^
On the pefietration of Balls into uniform [uniformlj/] resisting Subr
stances. %W,Mooee, Esq. — FhiLMag. iVb. 151.
Mr. Moore commences this essay by demonstrating the two
IMIowing lemmata. i»" If two spheres^ of diiferent 4iamktert|
488* Mr, Moore on the Tenefraiioh tif Baits.-
kud difTcrent ?pecifi'c gravities, impinge on t^o two unfform [tfnf-*
formly] resisting fixed obstacles, and penetrate into therli, thtf
forces which retard the progrci^s of the spheres will be as the abso-
Iiitt3 resisting forces or strengths of the fibres of the substancet
directly, and the diameters and specific gravities of th^ spheres
inversely. 2. The whole spaces or depths to which spheres im-
pinging on different resisting substances penetrate, are as the
squares of the initial velocitil^s, the diameters and specific gravi-
ties of the spheres directly, and the absolute strengths of the re-
sisting substances inversely." He then solves the following
" Problem. To find a general formula, which shuU express the
quantity of charge for any given piece of ordnance to produce the
greatest destrirction possible to an enemy's ship at sea ; it being
supposed of oak substance of a given thickness, and at a distance
not efi'ccting the initial Velocity of the shot."
Having, with a view of reducing it to practice, obtained a
general formula, Mr. M. assumes, as a standard experiment,
from Robin's new Principles of Gunnery, that an 18-po under cast-
iron ball penetrated a block of well-seasoned oak to the depth of
b| inches, with a velocity of 400 feet per second ; and deduces
' (S'+JD)o;
this conclusion, that the charge is =:'045 X ; where S^
denotes the thickness of the side of the vessel, w the weight of the
fball, afnd D its diameter. This result^supposes the resistan<!fe to
be uniform throughout the whole penetration; which is pot
fctrictly accurate, since the resisting force varies at each extreme
of the penetration, for a space equal to the radius of the balU
This defi ct in the resistance, Mr. M. thinks may be regarded as a
counterbalance to a small deviation in the variation ui the charges
iiioni tile theory on which his general formula is obtained. Aa
example is subjoined, and the charge to cause a cast-irou ball of
42 pounds weight just to pass through the side of an oak vessel
1| foot in thickness, is determined to be 61bs. 14oz. From this
resulting formula, Mr. Moore has also deduced a table of thtf
•various charges for producing the greatest effect for guns of 12,
i8, 24, 32, '36, and 42 pounds, .when the thickness of the oak
apd the radius of the ball varies by successive inches fromoae
-foot to five teet.
Some observations are added on the importance of this {xroblpm in
naval cngftgeraeuts, and several military operations, such as burst-
ing open of the gates of besieged cities, &c. ; and it is likewise re
marked, that when the thickness of the object is such thatitcaii-
not be completely pierced, or if it consist of brittle materials,
' that charge is to be used which will give the greatest velbpity tcJ*
the ball. When the saxne piece of oa'dnance^ howev<^r, is to be
Mr. Macron tie PenetriatioH of S^. ' tt$
fired a C6rtsiclerab!e number of tiiTM?s, this charge is Aot to be pre^
fcrred, on account of the longer time required between each
£ring. Another experiment is then assumed as a standard, froitt
Dr. Mutton's Exercises on Forces, and the requisite charge for ft
24-pounder, for bursting open the gates of a city, which' are mad«
of elm one foot thick, with the greatest ease possible, is deter*
mined to be 4rDs. 5 Joz. From the same experiment this generiki
formula also results, when the substance to be penetrated is thd
(S'+JD)
same sort of wood : viz. the charge ='0676 X j where
D
the letters denote the same things as in the similar expression for
4he penetration of oak. The author concludes, that the gates of
a besieged place may be effectually forced open by placing th^
gun in contact with the gates, and its muzzle from them, as th^
int)mentum of recoil is generally sufficient for this purpose«
• Obsercations. — ^There is not any former period of our history
in which the political situation of Great Britain has rende;'ed tho
use of balls so, extensive or so important as the present; nor is
there any department of the art of war in which experience has
so completely triumphed to the exclusion of theory as in thft
navy. It cannot be denied, however, that when these are Justly
combined, they are mutual aids to each other ; and the result iS
the most beneticial to the service, at least so far as it produces th#
greatest effect on our enemy in a given time. The accomplish-
ment of this combination we have always regarded as involviag
much difficulty, as it requires considerations of too abstract a
nature to be entered upon by men whose habits of life have in-
cluced them 16 think that they can do every thing independent of
theoretical principles. We were therefore glad to see the subject
brought' partially under investigation in the present essay ; but we
upprehend that Mr. Moore has avoided the chief difficulty with
which it is attended by an expedient which renders his results of
no practical utility. He considers the initial velocity of the ball
•as that with which it strikes the enemy's vessel ; hence, his theory
obtains only when the two skips arc in contact, that is, at a time
when the firing generally ceases.
It is well known, that after a ball has passed over a given space
it has lost part of its iiiitial velocity, and consequently its momen-
tum is diminished ; and therefore, upon the principles Mr. M. ha^
proceeded on, it would lodge in the ship's side instead of passing
through it ; and thus the maximum effect would be changed intQ
«ne which approaches the minimum.
With resjpect to Mr. Moore's concluding remark ' relative to^
iwrcipg open the gates of a besieged place by the recoil of a gun.
\
,4^ Mr, SievmoiCs Patenifor B m&chiHe/orJttfenng PTaief,
%€ must observe^ that little would be thought of that engrncn*
i)fficer who should.employ his meu in such a manner. Without
doubt, the momentum of the recoiling gun would be equal to tha^
of the ball in the contrary direction ,• but its impetus or energy^'
which generally determines the power of overcoming an obstacle^
would be less in the same proporrion as its velocity would be less
<^r its mass greater, than that of the ball ; since this attribute of a
inoving body is in thejoint ratio of its mom^intuni and its velocity/
•r in the joint ratio of the mass and the square of t^e velocity.
REVIEW OF SPECIFICATIONS OF PATENTS,
tlTFLISHED IN THE REPERTORV 0/ ARTS, MANUFACTURES, &C.
Mr, Joseph Stefhenson's Patent for a MachiTicforJlUermg and
purifying Water. Dated February , 1810.— jRe-jDcr^ory of Artsi
No. 98; Secoihd Series.
The body of this improved filtering machine consists of d
water-tight • vessel ; and the patentee prtfers the form of a rec-
tangular chesty th« length of which is double its breadth, and
this last equal to its depth. This vessel is divided into two com-
partments by a watertight partition which extends from the tojj
to within about an inch of^ the bdttom \ so that no water can pass
from one of these compartments to the Other except through
this opemng. In the lid or cov«r of this vessel, there are Iv^o
apertures or openings, one into each department; through th«fs^
openings there is to be introduced into each compartm^t of the
vessel, first, a layer or stratum of well washed siind. Upon thit
a stratum of coarsely pounded charcoal is to be placed, and then
another layer of sand The thickness of these strata of sand
must not be less than four inches each, and the layer -of charcoal
not less than two inches. When the body of the apparatus is
thus prepared, a hollow vessel is to be inserted into one of thfe
openings in the co^er, and made water-tight at the joint. The
height of this vessel should be from 18 ^ to 20 inches above the
jipper surface of the cover ; and the patentee thinks that th*
frustum of a cone, with its less end downwards, is the most con-
venient shape. The diameter of the lower end of this Vessel,
which should reach nearly to the upper surface of the top-stra-
tum of sand, should be about two inches. Into^ the lower part
of this hollow inverted frustum of a coue, some pieces of sponge
axe to be put and pressed towards the lower orifice. The use of
this compressed sponge is to detain the foul matter that may b«
coutaiaed in the water subjected to filtration; and wfaicli ja pai«^>
I
Mr. Stetensm*s Patent for a machine far Jiltermg Water. 4§|
. 8cd through this vessel ^imJ spopge^ thence denominated the dei*
cending branch of the apparatus. This part bf th« fbachiiie
is covered with a moveable lid ; and where there is the convctti*
ence of a reservoir to supply the water, ft is furnished with a
floating ball cock to regulate the quantity of water admitted into
the machine. There is also an air pipe inserted through the lid of
this compartment, about tke same height as the branch itself,
*for the purpose of pecmitting the air contained in the machine ti>
escape when the water is admitted. Another hollow vessel is
fixed vertically over the opening in the other compartment of the
apparatus ; this the patentee denominates the aseendrng branch,
and for which he prefers the shape of a cone plaeed dn its bast.
~This part of the apparatus is furnished with a cock inserted
above the upper surface of the highest stratum of 9and, for tht
"* purpose of drawing off the water that has been iilter;td, by dcB^
tending through the strata in one compartment, and asceni^&ng
• through those in the other. The whole may be made of anj
convenient materials and dimensions ; the patentee prefers the .
* body being made of wood and lined ^vith sheet lead, and the
branches of sheet or milled lead without wood, on account of the
iBcility with which the joints may be made water-tight by infant
of solder.' If the machine be twenty inches long, eleven and a
'half wide, and twelve deep on the inside ; the diameter of the
upper end of the descending branch ten inches and ahalf, two inches
at the other end, and nineteen inches above the upper surface df
the body, the other branch being ten inches and a half diame-
ter at the bottom and five at the top: 'then with a regular
supply of water this apparatus will deliver about 300 gallon^ df
filtered water in the space of 24 hours. The other modes of coa* ^
strut tion may answer the purpose as well as this ; one of these
is described by the patentee, but on the same principle as the
preceding ; in which the principal invention, that he claims as
his, is the use of the compressed sponge. This must be taken
out and washed from time to time ; the sand should be taken
out and washed two or three times a year^ and the charcoal
changed as often.
Observations.-- Tor other contrivances to answer this useful
purpose- we must refer to page 91 of our first Volume, to page $79
of vol. ii. or No. 51, of the Repertoiry of Arts ; and to page IT^t
vol. V* Mr. Joshua Collier also obtained a patent for an ing^
nious method of filtering and sweetening water, oils, and every
other liquid ; the specification of which may be tt%n in the lOth
•^irolume of the Repertory of Arts, old series.
If we reflect upon the method which nature pursues in the -
filtration of water, we shall find that those waters that descen4
ftvm hillS; though passing through sand and' rocks> are seldom
\
/^
4^ Mr» Sicoensoji^s PataUfor a machin€ for Altering Wafer*
perfectly pure ; but that those are the roost limpid, which \ij
' •sceoding, ooze out near the feot of a mountain* The cause of
Ubis ditierence appears to be this : when the water descends
■tbropgh sandy the finest and heaviest of the paiticles descend
iviih it, aoG| gradually penetrate through the sandy strata; but,
4)11 the contrary, when the water is forced to rise through sand,
■in order to make its escape, all such ponderous ingredients, by
reason of their greater speciic gravity, are left behind and settle
»t the boj^o* The lighter particles of fluid, therefore, remain
in the upper strata in both cases. Considerations similar to
.Jlbese induced Professor Parrot, of Paris, to give his filtering
.inachine the iorm of an i^Aerted syphon. The bent part of this
etppar&tus linay either be circular, elliptical, or a portipn of
•mpy other curve; and is to be. tilled with fine pure sand, nearly
iKhtbe top^of the shorter end, or that from which the water is*
•fevtti» The other end which receives the water, should be longer
•HI proportioD to the size of the filtering machiue. To this euA
ib attached a woollen bag, open at the top, and resting with its
Jovner part upon the sand. This bag serves^ the purposes of cci-
lecting the coors^t impurities,. and thus preserves the sand f^r *
M longer time from becoming foul. The bag, therefore,, may be
•occasionally removed and rinsed in xlean water, and then r^
plac«d» The mode of filtration likewise afibrds a very agreeable
•igbi to observe the most limpid fiuid penetrating tlie upper stra*
inm of sand, perfectly similar to that oozing from the purest
jiatoral spring.
Professor Parrot observed, from numerous experiments, 1*
rThat tjbe difference of the water level has an essential influence
•o the quantity of the purified water thus obt£^lned. 2. That 3
^prolongation of the stratum of sand does not considerably dimil.
^ish the product of the filter, but contributes remarkably to the
^purity of the fiuid. 3. That if the water be forced to pass tbrough
tihe ^ao4 with greater rapidity, it will not be sp pure as whep
.•proper time is allowed it for the passage. ,4. That a filtering
jBippariitus eighteen inches in length, from the extremity p.t which
the water eaters to that at which it issues; an^ containing
.al»out8 fqiiar« inches in. a cross jsection, with the diiference ol
two or ihtce ir^chcs in the height of the water, will yield about
J S. gallons of very pure water every 24 hours, if constantly
tttpplied. Hence it is evident that when a ^cater quantity )s
riequited to b^ produced in the sa^ie time, it is only ne«:«Sfianr
io iocrjsaste the size of the apparatus proportiana<lly.
After the perusal of these remarks, it certainly doess j^ r^e^
.<|iiii5e any argument to prove that Mr, Stephenson's mod^ty^
.jwlaUve to his claims of invention, as stated iu the following
iiteutenci^y i& veil faux^d^ ^' I beg) however^ no( to be underftlooit
^ Jiaving tntaQt to stats that the use of sand vmi charcoal foi:
^e purpose of filtering water is my invention, or that.iiliratioii
hy ascent as well as by descent is a new invention;, but aA
iuiving sin;iply described the kisd of ^arrangement which I haye
4bund well suited to give efficacy to the additional aid, which mjr
ixaprov^ macJtiil^e for filtering and purifying of water derives frona
(the use of compressed sponge, answers the useful purpose of keep-i
ing back a Ifirge portion of mud and olher impurities, which iq
'^e meUio^s hitherto most commouly followed, being allowed to
t«ome wittiout impediment to the materials employed as a filtre,
soon fill up their interstices, and consequently lessen ^nd at last
destroy their propeny of allowing the water to be transmitted
through them/' Mr. S/s invention is therefore reduced to that
of substituting sponge for tl^e woollen cloth that was previously
used for th* same purpose ; and whether or not this was of su$-
.cient importance to deserve a patent^can scarcely be a question.
Notwithstanding these circumstances^ we regard an appa*
TStos ras^e in- the manner^ though not of the same matt-.
rials, described by Mr. S. a^ well adapted to the purpioie for
wbicb U is designed, aiid therefore worthy of adoption ; par*
.ticulfuriy where the quantity of pure water required is con«
siderable ; ' while in other cases we prefer that invented by
Professor Parrot^ especially if a stratum of charcoal of three
^or fpur inches thick be introduced inte the lowest part of
' t^e machiioe. It may also be observed that the water pro*
,duced by Mr. Stephenson's machine will perhaps not be so
pure as that from Professor P's; for llj- x 10 =: 115
jquai^ iqfibeB in the surface of one of its ends ; and a^ 115 : 8
: : 300 : 21 nearly, the number of gallons produced In 24 hours
for every eight square inches of surface of Mr. S's apparatus^
or about one -sixth more than by the other in the same time«
We shall now conclude these remarks, with stating a few
circumstances relative to this inventien upon the authority df Mn
J. J. Hawkins, the person mentioned below, and which will shew
to whom Mr, Stephenson has been apparently immediately in*
debled for his knowledge of the mode of filtering, for which he hai
^ aequiml.the present patent-right, hoping that the importance and
utility of the subject will be deemed a sufficient excuse for having
dexteoded them so far.
About ^ eight or pine years ago, Mr. J. J. Hawkins of Titch-
field-street, and Messrs. R. and R. Peale of Philadelphia, wit&
«t view of making known the purifying quality of charcoal,
invited the public, by newspaper advertisements^ to attend on
a cer^in day* at the Merchant's Coffee House, in Ph^Jadel*
phia, fer the purpose of witnessing an experiment on the
means of purifying water. The appointed time being the change
bours, ^bout 500 spectators, consisting chiefty of merchatfl^
StIPPL.— VOL. VJ. ^ i
4S4 l/^« Jlobinson*^ Patent for a Mashing machine.
and captains of all countries, attended. A quantity of v«y
bad water was filtered through charcoal and sand, and part
of it ^afterwards drank by many of those present, who de-
clared it to be quite pure; and, after thanking Messrs. Hawkinii
and Peale, for the liberal and disinterested manner in which
they had imparled this information to the public, promised
'to make the circumstance known in all U^e places they might
Tisit. Subsequent experiments, however, convinced Mr. Haw*
kins that the sand was not essential ; ahd that charcoal, at
well as being the greatest sweetener of water, is the best snbstanca
through which it can pass to be rendered clear. From that
time Mr. ^Hawkins has been desirous of spreading this tise-
fal information, both in this country and America ; and among
cither means, early in the year 1808, he placed a filtering
apparatus on this plan in his " Muteum of Useful and Mecha^
fiical Inventions** in Titchfield-street, and endeaTOur^ to izn^
press the public with an idea of the superior utility of charcoal
over every other filtering medium^ Some time afterwards Mr.
H. was induced to make some of these filtering machine*
for sale, which were of various forms and sizes, and chiefly
composed of earthenware and glass, but as these were neces*
sarily of small dimensions only, be thought' of substituting
lead for this purpose, that they might be ejected on a larger
scale. With this view, we are informed he applied to Mr. Sle*
phenson, to know the expence, and without reserve, com*
municated to him all* his plans. Mt» H. however, did not
then know that lead is corroded and converted into white
lead by contact with wet c|iarcoaI ; a fact which he soon
after ascertained from a series of experiments suggested by
. an eminent physician ; and therefore gave up all further thoughts
of using lead. After the lapse of a few months from tb«
time that Mr. H. bad made* this communication^ Mr. S. ob«
tained his patent ; and , has since put up a si^n on his housn
in the very next street to that which contains Mr. H's ware-
bouse, styling himself " T/ie only manufacturer ef Hitertrt f*
\
Mr, Thomas Robin son 'j Patent for a Mashing Machine^ ^
Dated March 1SQ9. — Repertory of Arts, No. 101. Second
Scries.
In the centre of the mashing tub is an upright shaft bearing
a wheel which is turned by another connected by a ^haft with Iha
horse.wheel, or put in motion by means of stsam, wind, or vrater.
From this shaft a beam projects, one end of which is loosely c(^*
nected with it by means of a collar, while the other extremity
.runs ou the edge of the tub on two small rollers ; oue of wkU^li
ttr^, fTaitifs Paienifor t^Utmg macKnerj/far mtHs. 40i
"^ fixed on each side of the beara. Near the bottom of the tub
another horizontal beam or bar of iron revolves about the upright
•haft as a centre, one end of which is loosely fixed, as before, by
means of a collar, and the -other is suspended near the side of the
tub by a forked bar, the upper extremity of which is boKed to
the horizontal beam which rests on the top of the tub. 1 hrough
these two horizontal hart, two upright spindles work ; in which
are inserted vanes or blades of iron making different angles with
^he ones through which they pass. These the patentee calls agi*
tators. That which is nearest t? the upright shaft in the centre
of the tub is put in motion by a wheel supported on the latter
working into another fixed on the former, below the upper hori-*
sontal beam.
The wheel fixed on the spindle of the inner agitator communis
cates,motion to the other; and this again to awheel which works
into teeth fixed round the inside of the tub ; and hence the whole
is caused, to revolve about the centre axis. The patentee also
observes that this machine can be worked with great facility in
an oval tub, by jpnaking the centre shaft crank wise, and placing
a pinion between the, wheels on the spindles of the agitators 5
** whsreby the machine and the shaft will work in contrary direct
tions and give it, the requisite elUptic motion." When the tub
does not exceed thirty quarters^the inachine may be easily worked
by one man and a winch handle. In small tubs also one agitator
will be sufficient, while large ones require three or four.
" The agitators or stirrers of this machine working horizon^
tally, do not expose the goods or liquor to the atmosphercjwhe^e-^
by they wight be cooled. The proper degree of heat, therefore,
being reta^ed, dissolves the saccharine and other valuable pro«
pertles of the malt in the most effectual manner."
. OhservMtians, — It is desirable in mashing to have Jhe liquid
mixed with the malt as completely as possible without its tem-
perature being reduced by exposing an unnecessafy extent of sur-
face to the action of the aunosphere; and we think this machin%
well adapted for effecting this purpose.
9S
Mr. William Watts's Patent for Methods of combining and
disposing machinery^ and mpplying tht different powers of fFind^
Watery and Cattle thereto, so as to effect Improvements on Mills.
Vated September I %0S, —Repertory of Arts, No. 103. Second
Series,
In the machinery for forming a wind mill of great power, there
are two drum-wheels, having at each end circular iron plates-
containing cavities at regular distances from each other, to re*
mfv/e the axles of the sails, at the same distance from each oth^r
"^
4| 6 Mr. WatiiU faimffor ^miifAig mtchvveryfpf mills.
a's tbe cavities or notches in th^ ends of the wheitfk ;' tUM) WhidI
therefore fall into these catches in going roukid each dhint.^ OA
the end of every axle there is a small wheel, rnnning in a ehaiind
farmed in the framing of the mill, which iei'ves to stea<fy the asiM
{n their progress. Each of thesa axles supports a I'eetangalaf
frame, which has another similar frame £xed within it, andplla^--
ing on a joint or pivot at bottom ; to this la^t frame the sail U
fastened, which may be made of canvas or any other proper tntt^
terial. from each upright side of the outer frame a tuppOrt ex»
tends from the axle of the preceding, on which it turns, t6 tti
upper part of the succeediilig frame, where it play^ on a pifr.
These support the framei^ against the force of the wxti19 ; aikd dk^ft
motion at top and bottom permits the sails to turn roicrnd the
4rum wheels' at each end. In the upper part of each outer frame
is' fixed a pulley; ove^ which a rope passes which has 6ne end
fastened to each corner of the inner Irame or sail, and th€ oQitit
to a spring which h^s two grooved wheels running itr a channel i
this chatmel is contracted more at tbe upper than at the lower end*,
$0 as to produce any required resistance of the dalls ligainidt thtf
Wind. ' These sprmgs regulate the sails, s6 that when the impuM
of the Wind is great they give way; and render the extra force in-
effectual. The body of the mill may be of vanoud shaped and di-
inensions ; and th^ head may travel round on wheels, so aa to hi
susceptible of being placed at such an angle to the direction of th^
^ind that the sails may act with the greatest advantage; Tb^
under' sails being screened from the wind,' and' thie upper ones re-
ceiving it, they drive round the drum-wheels, to the shaft of
^hich the manufacturmg machinery is fixed. The number and
distance of the sails from each other' must also be regulated by
tircumstances. ^ Adding length to' the sails' increases the power
in proportion to the increase of saJ, without losing time; which
18 not tha case in the present vertical mills. The sails mast be
hiade full to form a concave surface to the wind."
^ The machinery for a floating or tide' mill is made in the same
manner ; the water acting against the lower sails, instead of the
wind aiffecting the upper. The floats may be made* of Wrought
iron or any other proper materials, and will goierally be brQader«
than deep. ^ They niust form a concave sur^ce to the current ;
knd if this run only one way this may be fixed, but if, as in the
case of the tide, it flow in contrary directions, they are mad^ to
turn on a pivot at the top and the bottom of the frame in which
they are supported.' ' The floats should always be as deep as the
current will admit ; a^ this increases the effect, as in the wind
mill. " \/
*' The improved machinery for a. mill receiving its power from a
fall of watefy consists of two or 'more metal wheels, fixed on the
kame shaft, and of the same diameter. The circiunfereiicea oi-
a.
s.
tkfBe bare stumps ^ cogs at a distance ff^m eatb' other atis^wv^
mg to the depth of the huckets, wbi^h are connected together b^
liaetal johiti, and work over these whe<^ls in continued suecessioii*
The buckets are so united that the cogs may prevent the weight
Of the water iu the descending buckets from causing those that
are empty to slide over the wheels without effectmg their purpose*
A small roller or two is also fixed at the bottom where the bQC'<
kets turn and begin to astend. These buckets are made of th^
usual shape ; the sides and ends are fixed, but the bottom is madd
to act as a valve, which opens when the bucket has descended td
the lowest point, and permits it to pass freely through the water,
and to ascend empty for the purpose of receiving another supply,
and exerting a fresh power by another descent.
** The action of the connection of buckets pulls round the wheels
by their circumference which is the extremity of the lever, to the
shaft of which is fixed or coupled the manufacturing machinery,
8> that every tOOlbs. of water employed in the fall acts with its fuJl
gravity on the lever; that is, producing lOOlbs. of power (setting
aside fnction) ; whereas, by the plan of employhig the water on
the semicircumfer^ce'of a wheel, as the present overs'hot and
breast, every lOOlb^. of water so employed produces only 50lbs*
of power (setting aside friction). The still greater loss of employ^
ing undershots which act by impetus or force of water is so wdt
(nown as to be almost unnecessary to bementioned, being allowed
|o ha double that of overshot and breast, or that^ lOOlbs. pro^
duces only 50lbs. of power (setting aside friction).''
The machinery for cattle mills is upon the same principle, and
consists of a similar connection of planks united oy joints, and
baving at their etids wheels travelling An a channel round the
drum.wheels ; the axis of which is connected with the machiner]f
as before. One of the drum, wheels may also bii placed lower
than the other so as to cause the cattle to act in part by their
gravity if it be thought necessary. The cattle drawing fronl a
fixed point, and turning the wheels and connected machinery by
the powef of their feet, enables tliem to work constantly in a
straight line, by which means they travel much faster with greater
ease, and perifdrm more work than when constrained to proceed
in a circle. • • V
Obserouiiuns, — We apprehend that Mr. Watts's inventions are
more calculated to introduce complication and expence into the
macliiiiery, than tcrafford an increase in the effectual force, of
the mills to which they are to be applied. In the vertical wind-
mill there is in reality very little loss of power, much less than in
any kind of horizontal mills, where more than half the surface of
the sails is always unemployed; and the oblique direction, in
which the wind isr made to act on the sails, must iu this arrange*
49t ^ Mr» DffDy*8 repf^ to Messrs, ^m/^LusMoe and Thenatd.
ment cause a great and unnecessary strain, and consequent fric-
tion in the parts which run on each other. In the common over-
shot water wheel, there is actually no material los« of power ; the
calculation, which suffers one half of the power to be wasted by
the application of the buckets ^o the whole semicircumferencey is
completely erroneous. We confess that we have not always been
equally aware of the fallacy of the argument from which this in-r
ference is drawn : but it is sufficiently confuted by the demonstra-*
tions of any of the best modern authors on Hydraulics. In the
mode of applying the force of cattle we imagine there is no man»r
ner of novelty. See Phil. Trans. 1734*
CHEMISTRY.
A reply to Messrs. Gay-Lvss AC smdT:pzvAB.D's answer to tht:
Analytical Researches^ SfC. published in the J (mm, de Physique^
for December^ I8O9, By Mr. Humphey Davt. — Journ,de
Fhys, vol. 70. /
Ivthe Bakcrian Lecture for 1808, some experiments were re-
lated whif h seemed to shew that sulphur and phosphorus con-
tained hydrog<?n, and probably some oxygen; but it was said>
that the phcnoijiena might be explained, by supposing that hy-
drogurcttcd sulphur and phosphorus were formed by the action of
acids upon the sulphuret and phosphuret of potassium. And inr
the Lecture for I8O9, the first ideas on the subject were cor-
rected.
Several circumstances tend to produce errors in respect to th©
action of potassium upon sulphur and sulphuretted hydrogen,
particularly the absorption of the latter even by concentrated
muriatic acid ; the difficulty of acting upon the whole of the sul-
phuret of potassium by an acid, when a large quantity of sulphur
is used, and the action of potassium and sulphuret of potassium ^
upon glass.
In some experiments made with Mr. John Davy, muriatic acid
latiirated with sulphuretted hydrogen was used, and the glass tube
was lined with sulphur; the volume of sulphuretted" hydrogen
disengaged from the sulphuret of potassium was very various, and
generally less than the vqlume of hydrogen produced by the ac-
tion of an equal quantity of potassium* upon water; but whcii
sulphuretted hydrogen was used, the volume was greater,
1.2 grains of potassium, with 1 0 grs. of sulphur, yielded 0.85
cubic inches of hydrogen. In another, 1.4 gr. of potash, and
iabout as much sulphur, produced about 1.36 cub. in. of sulphu-
iretted hydrogen. The results of three otht>r experiments arc here-
•xhibifedL
Jiff. Diofs reply to Messn. G(n/*Lus$ac ondThenard. 499
Sulphuretted hydro- •
9alpbaT. Potassium. Gas emitted> gen disengaged Sulphuretted hydio
Crraina. Grains. or absorbed* by the acid. gen disengaged.
1 A ...• '•••• — . ,45
10 1.4 +1 46 — . .64
•JO .6 +02 .... —. .6
In all these experiments, the heat produced is very great;,
^hich prevents any very uniform results, because the potassium,
in some of them is flung out of the middle of the tube, and in^
others (as in the second) the uncombined potassium is envelopped
in the sulphurot of that metal, and escapes decomposition.
As to the acti«n of phosphorus upon potassium, Messrs, Gay*
Lussac and Thenard decompose the phosphuret, with hot water,
eo that pKoaphate of potash and much phosphuretted hydrogen,
are formed, whereas to form proper conclusions the potassium
only ought to be oxidized.
Phosphuretted hydrogen, contains more than its bulk of hy-
drogen ; and when strong muriatic acid acts upon phospuret of
potassium, or phosphuretted hydrogen, or phosphorus, a lesg
quantity of gas is obtained than when potash [potassium ?] acts
upon water, as for example :
Hydrogen holding phospbons
Pliosphonis. Potassium. Gas emitted emitted by the acid*
Grains. Grains. or absorbed. Cubic inches.
10.0 1.2 ..,. . 1.1
1.0
0.9
+.05
0.9
10.0
l,2S
+.U
1.15
fliosphuretted
■ ■
hydrogen.
Cabic inches.
-
'
3.87
. 0.9
+ .5
OJ
1.75
0.3
-h.2 \
0.1
2J0
0.7
+.2
0.6
There is some contradiction in the assertions of Messrs. Gay-
Itussac and Thenard* In the Mem. d'Arcueil (11.304) they say,
that potassium heated in phosphuretted, sulphuretted, or arseni-
u retted hydrogen, abstracts the solid infiammabie, and also some
of the hydrogen ; and that the dccoraposition of phosphuretted
hydrogen is accompanied with flame. But in their answer, they
«ay, that potassium does not abstract either phosphorus or arsenio
from hydrogen, and they make no mention of any flame in decom-
posing phosphuretted hydrogen. The latter, indeed, has not been
observed, although a lively flame always accompanied the decora*
position of sulphuretted hydrogen.
The French chemists consider as a novelty the fact of sulphur
retted hydrogen containing an equal bulk of hydrogen, which was
expressly mentioned in the Bakerian Lecture for 1808. As th#
JBuxturc pf aj-s^nic and potassium yielded Ic^s hydrogen than
MQ 4fr. J)mnf$ t^ to 3tmrh S^lmw,4ndfk0tfiid:
potassium alone, they say tlKbt it 9ught to have been concluded^
* Ihat the arsenic of arseuiAretted hydrogen oemtaimNl some oxygen ;
f)Ut it 9fm well known that hydroguret of arsenic existed.
As potassium, heated .with sulphuretted hydrogen^ produces
the same quantity of hydrogen as is produced by the action of
potassium upon ammoniac and water, they conceive this to be a
proof that potassium i\ a hydrc^ret ; but from Mr. Dalton's doc-
trine of proportions, that event must take place which ever ^eory
be true.
The phenomena of the formation of the fixed alkalies may be
explained t)y supposing them to be compounds of water with
unknown bases, and the alkaline metal» as compounds of the
same bases with hydrogen, but no water can be obtained-from the
alkalies. And, in fact, the potash formed by the cdtnbustion of
potassium in muriatic acid gas contains nearly 9 per cent, less
water than the standard adopted by Mr. Berthollet. Potash
which has been melted by a red heat, contains l6 or l/'per cent,
of water ; that formed by the combustion of potassium in muriatic
acid gas being considered as the standard.
All the mttalsare re-produced by the negative pole, they only
differ in their combustibility ; and the power of the alkalies to
saturate .acids is, like that of all other melallic oxides, exactly
proportional to the quantity of oxygen they contain. This would
apply equally to ammonia considered as an oxide, if the hydrogen
/yielded by the moist amalgam!^ of amitioniac is taken as the
basis.
The application of potassium to the analysis of the acids was
early adopted ; and the fluoric and boracic acids, and the water ^
'muriatic af id, were decomposed before any chemical metliod was
known of obtaining that metal. Messrs. Gay-Lussae and The-
nard have entered upon these researches, as though they were
entirely new discoveries ; and although the properties of potas-
Isium and sodium, as detailed by them, were mentioned in tlie
'Bakerian Lecture for 1807, they do not mention this circum-
stance.
It is probable that many ideas started in the Bakerian Lectures
will require revision ; and particularly those relating to thp car-
bonaceous matter, the proportion of oxygen and base in boracic
^cid, and the decomposition of fluoric acid : for when new objects
are first examined, it ii impossible to form . accurate ideas of
them.
^"r
Answer hy Messrs, Gay-Lussac and Thuva^d,
. Miu Davy positively admitted the existence of oxygen in sul-
phur, phosptiorus, and in sulphuretted and phosphuretted hydro*
Mr. IDaTp's reply to 'Messrs. Gay-Lnssac and Thenard, 501.
gen sas, in' the ftakcrian Lecture' for ISOiS, dtld did not renounce
FhisideaiA thit oi\m.' •• ' :•' *'•'''■.•'*. * ' ^'\ \
No hydrojTuK'tted sulphnf 6?^p|i^otpfiorus' was formed by treat-.;
ing the sulphurtt or pnosphulfer o|" potassium, with a hot acid 5
and more sulpbU ret ti*d h^^drogcn was alNvays obtained than could
have been given by the liydVogen in the potassium.
On repeating fqr niQre th;yi ^t^- tipes the exnerimentsibrmcrly *
made, €ulphuiH}t6f*pota*sium*has always Ibeeii'^^'und to yields by
means of acids, sulphuretted hydrogeh ec(iiiil W l)*Ulk to the hydro-
gen that would have bceM'^yicid'pd' b^ thepojui^feiurn*'ha4*it been^
treated with Vvaiet*'; atid tlVe^&Ti^^ result was ob^^f^d'when feul- ^
phu retted hyflrogen gaj ,was .tr^att'dXyith pbtasalym. And tlicsc
cxperimelifs have\nic(i been l>}p(iiiSd scvtral ti'me^.' so that th'ey.
are ccrtamly trtic. ^ • . , u . . f.
The reason that^Mr.'pavy cffd not otJtafiii' th>'^ results with
gulphuret of potassium \i^ riot* Rtjowii ; but'hi^ fiiistake respecting
•ulphuretted'hydrogon ^(^ms to havi aijisen fi'om his not having
observed that s ul [Shu retted hydrogen ^as, procur^*^ from sulphu-
41 larger proportioi
The phosphuret "6^ b8tass*iVm; war ffot only treated with hot
water, but Alsd withawdsi arid'lhwfeTva^'^constantly obtained
more phosphur^tted hydrogen gas. than was , equivalent, to the
hydrogen that the potaSsiuft \Vould hUve yielded with water.
The explanation^iven by Mr. Davy, of the cotnjJarative action "
of water or acids upon phosphuret of potassium was drawn from
the Journ. do Physique fdr December, I8O9. ' He did not men-
tion in the Bakerian Lecture for 1808, that he treated the phos- *
,phuret with concentratijd muriatifc acid, but expressly said, in
one place, that he used diluted , muriatic acid, where, in fact, it
ousht not to have been diluted*. Of course, some of the water
might have been decomposed by the phosphuret, and therefore
he ought to have analyzed the ph"ospl^ui*etted hydrogen, ill Order
to discover the exact quantity of hydrogen that it contained.
In the .Mem. d'Arcudl^ potassium was, indeed, said to have
absorbeJl some* of the hydrogen when heated with phosphuretted,
sulphuretted,* or arseniurette'd hydrogen,' because an exqess of "
potassiurh was used ;*'b'ut*'since that time, in the 3ourn. de Phys.
Dec, I8O9, it is said, that potassium separates all the hydrogen *
from its combination with phosphorus or arsenic, which is no real
contradiction, as, in this'cas'e' the gas was' purposely in excess ;'
arid by proportioning the qua?itity, hydrogen may be either ab-
sorbed or noi by potassium. ' • * ' ' *
SUPPL.-r-VOL. VI. 3 T
$0Z Mr, Daryi reply to MeiSrs, Gay-tjuude and Tiamrd,
There vias a double cmn* committeJ in describing the experi-
-ments upon the action of potassium upon sulphuretted and phos*
phurettcd hydrogen, in respect to the appearance of flame. Both
the exptTimcuts were performed at one time, and the on* was
written down for the other. In reality, phosphuretted hydrogen
is absorbed' without flamc» and sulphuretted hydrogen with
. fl^me.
It may still be supposed, that if Mr. D«vy had known the action
of arseniurcttrd hyorog^n gas upon potassium, he would have
eooclud(*d that this gas contaim*d oxygen ; for, on treating the
arsenic with water« it docs not yield to much hydrogen as the po*
tassium would yield with water.
The objett of the researches published !n tfie Joum. de Phys.
Dec. I8O9, was not to determine the existence of hydrogen in
sulphur or phosphorus, but^o determine whether they contained
oxygen ; to which opinion they were decidedly hostile.
Mr. Davy says, that before he knew any method of procuring
potassium or sodium, he had discovered that fluoric and boracic
acid, as also the water in muriatic acid, were decomposed by
those metals. It would be very ensy to prove tlie contrary by
Mr. Davy's own papers, and also to skew that his discoveries were
all anticipated in France, as will be shewn in a work now at the
press, in which all the objections of Mr. D. will be answered, and
the most impartial justice admitiistered to him.
The following is a summary of the points in dispute with Mr.
Davy :— .
1st. A solid hydroguret of potassium exists. — Mr. Davysaya
he has not been able to obtain it.
2cl. Potassium does not absorb any more ammoniaCal gas when
dried by means of lime, than of common ammoaiacal gas. — Mr.
D. believes the contrary.
3d. The ammoniuret made of potassium and ammoniacal gaa
at- a low temperature, being gently heated yields 2-5ths of unde-
com{K)se(I ammonia, and l-5th of decomposed ammonia by a
stronger heat. — Mr. D. believes that it yields much less.
.4th. The ammoniacal amalgam is a combination of quicksilver*
ammonia, and hvdrogen.^ — Mr. D. believes it to be a combination
of quicksilver with a peculiar metal, the basts of ammonia.
^rh. This amalgam Is not decomposed by the air, nor by sul-
pHuric acid ; neither does it become covered, when exposed to the
atmosphere, with a coat of carbonate of ammonia. — Mr.D. be-
lieves the contrary.
6*th. U is very easy to explain the great bulk of this amalgaim
by the very slightly condensed state df the ammoniacal gas ana
hydrogen that it contains.— Mr. D. rejects this explanatioUi aud
says that he cannot explain the phenomenoa.
Mr. Davti*s reply to Messrs, Gay-Lussac and Thenard. 503
7th. Azotic gas (nitrogen) is a simple iubstancc, and is not
composed of oxygen aiid hydrogen. — Mr. D. says It is torn posed
of oxygen and hydrogen;
8th. Potassium produces with ammonia the same quantity of
hydrogen as with water.-^Mr. D. says, less. '
9th. Ammoniuret of potash, or the olive matter produced b j
ammoniacai gas, does not yield the smallest bubble of hydrogen,
when put into water. — &fr. D. believes the contrary.
10th. Neither sulphur, nor sulphuretted hydr^ygen, contuii
oxygen. — Mr. D. says they dp.
1 1th. Neither phosphorus, nor phosphurcttcd hydrogen, con*
tain oxygen. — Mr. D. says they do.
19th. Potassium produces, with sulphuretted' hydro^n, tht
same quantity of hydrogen as with water. — Mr. D. says, that it
produces more with sulphuretted hydrogen than wkh water.
13th. Sulphuret of potassium produces with water the same
quantity of hydrogen as the potassium alone would do. — Mr. D.
says, that the bu& of the suq>burf tted hydn>gen is less than diat
of tile hydrogen.
14th. Ammonia is composed of three parts in bulk of hyclrogen^
^nd one of azote ; it does not contain any oxygen. — Mr. D. lias
varied extremely as to the composition oramtnonia : he has men*
tioncd different proportions of oxygen; hydrogen, &c. at different
times ; and has so often changed his opinions in this respect, that
his present opinion cannot be known.
Mr. D. has lately come into the French opinion respecting the
7th, 8th, 9th, 10th, and 11th articles, but still retains his own
opinions on the others.
mmtBSSBmmassssssaamm
On the ckangt of poim$tiwm ami Sodium mi9 ^kftdJlkaUes. By
Mtitrs. Gat-Lus9ac tmd THEVAmo. — Momitm^^ 4^A JWy,
1810, and Jmtm* dc Fkynque^ tml. 71.
Wmkv potassium b burned in oxygen gas^ by rneans of heat, it
absorbs thrcip times as mudh oxygen as is necessary to form potash.
Sodium treated in the samemanner absorbs only once and an half as
much oxygen as is tt^essary tp form soda. ' Atmospheric air
gives the same results. Potassium absorbs nearly as much oxygen
in the <oid as when heat is employed ; but sodium absorbs scarcely
any in the cold.
'The weight of the oxides is equal |o that of the metal employed
and of the oxygen ; they ^re orange coloured, fusible at a mo-
derate heat, and when put into water, they yield immediately
either potash or soda, and much oxygen. At a high temperaturfe,
these oxides are decomposed and reduced to ^Iktlies by almost
So* On the change.,of Potassium and Sodium iiiiujixed Alktlitt.
evpryoncoftUc.coiubustiblc bodies. M,!iny of thcsf di^coropositkini
ttkc place with Aanie, cspccinlly that ptff^'idr of potassium with
phosphorus, calcined charcoaf, su'fpliurj,phi«ii)huirettcti and sul-
phuretted hydrogen, arsanic, tin, ,?iiic,JAtip(tcr, sawdust, resin,
and animal subslanccs; and tl^ of jOMiiu.uf sodium uitb pbosi-
pborus. , ,, , , .^ , .^ ,,, ^1 ,, ,. ■• , . ,.,,.
"" ' iljes^tjwi^pd wjtVcjJrb'oiiiC ai^'iijifii, yield »Jkaliiw car-
; is^jii^^ji3i^^ijd,|,,-0\j!dc,of poiaasium anfl
tonaies, and o-\)gcji pas is^ jii^^jisi^;
(ijphurous gas, jieldsulghatoaiid, «,^y^|J],; iv^iag.oi s^acnm ana
■ulphurouB gas yield only miich suJBhjit^.aiid a, tittle s'uii>liucL-t;
hot|he least trace of n)oiatunj.\>^a^^'ervaJiIein ltics(i<;xfi(rjmoits,
anUtbc wcightoftHepr6(luc«i» c;fLVtt^^^'V''fS"'l. -°^''*'?^'^ ^^^
l^id th^ wcreabsc^b^d. .' ' ,. ^, . :_ ,'^ ,'" . ' ■'■
'As'jiio volin'^e produces foniKct in ihc'c()jnj)_i»tion9^ipota.sliapd
loJmtp,' il is,jy)'|plfttjj9.t 'f tbo nict|«ls' c5ujaip'.hvdlp^>n; ihusul-
ri,jiii(t/'san|,C3rbon«es.9^Fpotw}i;iiy_isi^l.j;^
Iff me^ of ihcsg^alUijfi^ mijjiCo^jjh il^niuch wat^^
ijf^-siippojed tf B^htfiHrnrnhm W3f m ff^^y r-t'^if' ^^
at avery hinh tcmprratnre ; which h possible, bat jtot [jroy^dat
vcL, ^^n(H{jia>.^c.(ijEdGd al|ta|j«.,w(;iil4i99"'*'"W^'*^'''?9?!i' ■*?***
i(^an^B>HrieJ^y ll)Brcfih'??ji(l:iP(''^''»'^<itV,os_thcy liioulU.'cjjiitaJii
ppt on]y^ tbc imcrfh^t^'paralos (Voiii ,l^f in' wlien. tlicy aij^^iaa-
fcined with fu;:ifls,,.b"t also thai n)iit;]i the ;Bi(lt5 ihciiiscJves. ^taio,
-^ Several. gVa'wiiit^(<iUiU'ter-dracb!i|s} .of|paiass,iij(b _^iWiodiuin
were converted' into altrttics by'oi.jp(>>iirc t(j!Dipisl airjand' after-
wards saturated with dilutj:dsuij)liii|iicp9JiI ; and^at^fi^aaie'timp,
the sanu' acid wasjiniuvated wUti j^uij>^|!o^as|j,,jfnd s^a tli,atljad
nitcd : by which it was found that po't^l ■Wrfei"V?ftP''^
cent, of water, and soda 34, supposing potassn'ini aiid sodium to
b*-Miiipl» bojiwi fkm itnUnwat jJm^.vnwiwd.wfctQ-iMJa. by
placing it upon a small plate of platina, in dry carbonic acid gai
upon quicksilver i^oi* on raising ftn^tiimpnMare^ llio:water'run-
dfwn thesidwc^'tkfabcl^leK.^ BjlitbisJmeaQsiorAkfc uroof sul-
phurous acid gas, the water conta^ned.'ln SmiUigikntmes i(ll-83ud
fifftgrair n l|c r^^j:red visibls- ^, .■ ■
As frbi bieiitsVjPptassiiini and sodium ab-
sorb in c( i than 13 necessary to (he constitu-
tion of a hcthcr ui,^ ^^Ikalies' would absorb
oxygen 1 t.' ■ In Ufit', when alkalies which
Kavebeer n.wat^r, they emit oxygen. Nitre
also', whe ilkalt'fhat emits oxygen on being
treated withwiyejj B>indthc s^mc flt^s ifQ doubt. happen to iiitratc
of soda, l^astly b^ry tes, wljctjicr it be, p«jciired from nitrate of
bary tes, 'or froip' ami's'turc'of carbb^a't^ ojfb'aiytes and lamp-black'
calciijcd lii a'strong foi^e iiro, absorbs 'by agcntlehtat much
bxy^a, 'and|lij^.i^i» meahsac'qviircs (he property of afterwards ab--
Oh the change of Potassium ewiSadhim into jixed Aliallef.'haS
Gorbing a considerable quantity of hydrogen with a very sensibia
emission of.light, by wbich \\js changed into fuybjc barytas.
All thcsc"focts have caused Messrs. Gay-Lussac and Thenord
to incline to the opinion that potassium and sodium are simple
Obseroationa. — In our last number we gave the two first papert
in this leng series ofcontrovcrsial papers, and now present our read-
ers with the third, and this supplementary notice, by the f|rcDcliche-
hiistswhohavccngagedin the controversy. Alink,.hqw^ver,,''iith9
controversy is still wanting, namely the paperjtublishcd'by M^gn.
Gay-Lussac and Thenard in the Journal' 'de Fhysitiiic for Decem-
ber J8O9, which produced Mr, Davy's aniinadversiofls,'4bstniii;'ted
in the preceding article. As the Controversy is important, we di,^
tiut waitfor the arrival of the ciipy'of th'at Journal ; but present
our readefs with an abridgement of ajl that has hitherto reacted
this country. ', ■■''■. '"■■ ■ ' ''' '"'
. It 'mW be-seen la tills present article, that I
and Thenard ijK luiTuccd kt length to cpijside
probable opinion that the alkaline ihcttilsareni
Simplobodies; and that they areconvertedintoa
tion vyith oxygen. But the^ still'JifierfromW
affirmed th&t these metals formc'i'tlic'alkaliesii
whereas the rcscarches6f'McBsrs.' Gay-Lussac ai
that the Qxldesofthealkalirieinetals'obtained
Combined with more' oxygen than is necessary
of fixed alkalies ; and this must be got. rid of, i
addbd Epfbre the alktJies are "feally* fonned,
are in feet hydrates of the suboxides (prbloxi
Aietals, and not oxides Q)eroxidei) ofthem7as n
ttom the description given by Mr. Davy.
' As to the tergiversation and frequent' vacillation of opinion witt
which the' Fi-encfi theniists charge Mr. Davy,' and tlie maC
tentlon and: Hesitation on their part,- to'give him the praise whicl(
hs ' conceives to be his due, it is tiot- biir province to enter into
these personaldisputes, which we lament. Nor indeed should
we be proper judges, some natural pai^ality to a countryman,
sbmc ignorance of those minute peculiariti^ of a foreign language,
which may sound perhaps excessively haTsh and degrading tp 'a
liattve, migtit always b« alledged against our judgment. 'We
strongly suspect 'that 'Mr. ^Davy's frequefatuseof the phrase, it is
-Hot true fil n'est pas vrdij rankles ih thii'Winds of his opponents,
(Tomtheir extreme cai^ to produce' hi^'o^n words in quoting from
his formerpapers^ idcbough the irripressioA is attempted to be con-
cealed by laboured professions of cs'tcem for him.
( 506 )
mm^mi
\
Chemieal examination of tie Indigo and Woad Planti, By JIfrr
Chevkeul. — jlnnaies dc Ckemie^ xoL 68.
The leaves of the voad plant ground yielded a very thick,
^ccn, mucilaginous juice, which, on being filtered in filtres
covered with panes of glass, in order to avoid the contact of air,
left gircen tecula.
Th^ filtered juice was yellow inclining to red, slightly acid,
changing to green by exposure to air, and becoming covered with
coppery pellicles. On being .filtered twenty-four hours afterwardi
. It left indigo on the filtre. iTie filtered juice was red, and slightly-
acid; acids separated from it vcgetu-animal matter, and changed
St green ; alkalies and alkaline earths changed It yellow^ and dis-
en|^agtd ftminoma. .It yielded ^hite codgulum by heat, the
9uperhatant liquor becoming clear and reddish. The coagulum
yis^ greenish in tome parts, and reddish in others ; boiling alcohol
separated tl^ green matter and' indigo that occasionedtliese spots,,
and left it white. U turned brown in the air, was insoluble in
boiling water, aiid yielded animal products on distillation ; its
diarcoal left bluish ashes, composed of the phosphates of lime
and iron carbonate of lime, and a little silica. The coagulum
yielded bitter matter and oxalic acid by nitric acid; it was dis-
solved by aqetic acid.
The liquor filtered from the coagulum, on being evaporated to
the. consistence of a syrup, depo8it€|d animal matter, and yellow
extractive matter. Ali*phol poured on tlie syrup became of a
fine rose red ; it was acid, and on evapuratiou left green matter
similar to that formerly mentioned in the paper on indigo. It
derives its green colour from being combined with au acid, as it
appears to be reddish yellow when pure, and red when combined
With alkalies and alkaline earths ; for when diluted sulphuric
^gid i^ added to it» solution in potash, the ired colour is changed
to yellowish and it is not till an excess of acid is added that it
t>ecomes green. It is probably the acetic acid that was originally
coinbined with the green matter.
The liquor separated from the green matter was reddish brown;
acids (Changed it green, and flung down green precipitates ; alka*
lies changed it to red mixed with yellow, because it contained
^ome yellow extract. This liquor contained muriate of ammonia,
nitrate and muriate of potash, and acetate of potash.
The substance left by the coagulum when treated with alkohol
was aliaost totally soluble in hot water. It was red, not changed
green by acids, but of a clear yellow; alkalies chaiiged it to a
Chemical exMminution of the Indigo and fFoid Flant$* 50J
deep yellow: alumed silk was tlycfl of a yellow colour, a Utile red,,
by this solution ; so that it contains yellow colouring matter ana-
logous to that found in many of the common kinds of indigo, and
in many vegetable juices. It also contains a vegetable salt, with
base of lime, and some traces of animal matter, as i^so a viscoua
matter of a gummy nature.
The part that was not soluble in boiling water was white and
crystalline, and appeared, on examination, to be citrate of lime
and magnesia.
The juice of the woad plant yielded, on distillation, a while
liquid, which contained an oily principle, smelling like green
French beans, ammonia, and sulphur. The last was discovered
by paper painted with carbonate of lead, and hung in the re*
ceiver, being rendered black. This is a better metliod of disqo*
vcring sulphur than immersing the paper in tb'e liquor itself. The-
ammonia seems to be produced from the decomposition of some
ammoniacal salt.
The juice of the woad plant, distilled with weak sulphuric'
ticid, yielded a liquid that contained acetic acid, and also prus-
•sic acid.
The juice from which the vcgeto-animal matter had been coa-
gulated and separated by heat was precipitated by acetate of
lead; a yellow curd was obtained, foni^ed of the vegetable acid,
that was combined with lime, yellow extractive matter, green
matter, and some remains of vegeto-«nimal matter. This curd,
decomposed by sulphuric acid, yielded an acid that appeared to
be the malic^ Sulphuretted hydrogen was passed through the ,
liquor, which had been treated with acetate of lead ; and when the
liquor was evaporated, it yielded crystals of nitre ; the mother
water was reddish, and contained much acetate of line, and the
acetates of ammonia, magnesia, and potash, as also a muriate,
which were all taken up by boiling alkohol. The insoluble re£;«
duum yielded to water, gum, nitre, and lime. The acid to
w)iich the last was combined is not known. The reddish colour of
this solution was not owing to colouring extract, for neither ace-
tate of lead nor muriate of tin precipitate it. The part net taken
up by the water was white like starch, but its quantity was too
small to be exaraioed ; it might be a citrate.
The green fecula left on the paper when the juice w^as filtrated,
yielded, when treated with cold alkohol, the greatest part of its
green resin ; it afterwards yielded to boiling alkohol, wax, indigo,
and the remaining part of the green resin ; the wax separated from
the alkohol when it cooled ; and on the liquor being exposed to
the air for 15 or 20 hours, the indigo was precipitated on the
sides of the vessel, which was washi^d with cold alkohol in order
to separate the remains of the green resin. The substaacc' hit
506 dhemical examimtion of th TttJigo and tVbad Pfanfs,
undissolvt^d \iy the boiling alkohol, was vegeto-animal matter,
retaining some indigo, and gi-een resin, which adhered to the
iregeto-animal matter in the* same manner as indigo adheres to
Woollen stuiBil Some woody fibres are also left in this mass,
which rietained the more' indigo and green resin in proportion to
its dryness ; for when the. yet moist fecula was treati^d with boil-
ing alkohol, almost all the green fesin and indigo were taken up ;
and then, if the quantity of green resin was considerable, it re-'
taincd much of the indigo in solution ; so that it is always best *
to treat fresh fecula, if it be desired to discover the quantity of
indigo it may contain, with cold alkohol, in order to* dissolve the '
greatest possible quantity of green resin.
The^cakc loft by the woad when expressed,, and which retained
tome of the green fecula, was divided into two portions. One
yielded ashes, from whence water extracted much carbonate of*
potash, with some sulphate, muriate, and phosphate of potash.
The insoluble residuuip left a little silica and charcoal onsolu--'
tiort in muriatic acid ; the solution itself evaporated to dryness ;
llnd treated with alkoHol, yielded the muriates of lime, magnesia, '
and iron ; the undissolved part contained phosphate of lime, man-
ganese, probably united with phosphoric acid, and a little iron,'
The other^iart; of the cake' was treated with boiling alkohol, which '
Wok' up' wax, some indigo, red matter of which hereafter, green
rdsin and hitre. The alkali obtained from AToad by combustion is •
ptoduced from this last salt, of which the leaves contain so much
that it is sufficient to ignite them when dried to sec the nitre take
fire with the charcoal : thcf residuum left by the boiling alkohol,
trcat(*d with muriatic acid', iiUd the excess of acid being saturated
with ammonia, did not }deld/the granulated precipitate attached
to the sides of the vessel that distinguishes ox^l^ale of lime. Mu-
riate of lime was obtained, which probably came from malate of
lime.' The woody fibres were dyed blue by the indigo ; they left "
whitd ashek, formed' for the most part of silica.
'The juice of the young shoots of the indigo plant coni&mod
indigo ad minimum, vegeto-animal mattef, green matter, 3rellow
extractive 'matter, in much less quantity thaS in woad, mucilage,
a calcareous salt, probably the malato, and alkaline sialts. The
fresh juice is not acid, but after 24 hours it reddens" litmus. The
green fecula yielded indigo, wax, green rtrfn, ariimal matter,
and a peculiar red matter.
Ten grtimmes of the real indigo plant yielded moire' iadigo than
300 of woad. By cutting woad at different periods of its growth,
and examining a stalk of indigo, Hi the spring it appears thatthei
indigo, as also the green matter, disappear. Moisture seems to
favour this decomposition, and the Ibi'^uation of yellow extrac*
CkefHical demmoHm (if ike thdigo and FToadPhmts. / 501
iive matter, while flrjtiess preserved the indigo at its maximma
^ oxidizeiAeiit.
The indigo ad niaximhiu contaiiWd in sdme parts of woad leases
preserved its blue colour, while that ad minimum contained ia
other partd wad decomposed when their foetstalks were immersed
in Water. Bergman has shewn that ihdigo separated from the
plant niay also be decomposed, in which case the indigo seems
to be previously reduced ad minimum;
The indigo is contained in the leaf, and iii its footstalk, as the
part of the stalk broke off, especially if the. juiced is squeezed'out,
becomes tinged with blue after some time. It is singular that a
body so oxidizable as indigo ad minimum shodld be found in those >
parts of a plant which frequently emit oxygen ^as.
Th(} green fecula of robiniaaltagana being treated with hotal*
kohol, the solution deposited on being cooled and left for some
time a granular matter of a tine red colour^ whieh was insoluble
Jn water, slightly soluble in cold alkohbl, sohiye in boiling alko-
hol ; the solution is of a fine yellow, and on eva^ration, it leaves
yellow circles on the sides of the vessel, and a fine red mass at
the bottom. Cold alkohol poured on this mass became yellow
itself, and' left the mass render^ paler; boiling alko*
bol turned it yellow, and the solution b&d the same properties
as before, so that the yellow matter is merely the red in a mora
divided state. Its colour was not changed by acids or alkalies.
Some traces of it were discoverable in the fecula of woad and
indigo. \ . ' ' . '
. This- red matter differs from that which causes the red and yel*
low colour of leaves towards the end of autumn. For cold alkohoj^
forms a yellow solution of them, and on evaporation the redco«'
lour appears. Boiling alkohol is more effectual as it dissolves the
wax that hkiders the action of cold alkohol. If leaves partly
yellow and partly red are used, the wax carries down with it the
yeUow colour, and the red remains in the sqlution. _ The red co-
lour is soluble in water to which it communicates its own colour,
the solution becomes yellowish green by alkalies and then red by
'acids. This red colour has a great analogy to the colouring n^at*
ter of fruits and flowers, which is blue when pure, red when com-
bined with an acid, and greenish yellow when combined with an
alkaU. As to the yellow colour it becomes reddish witk alkalies,
and yellow with acids.
The green fecula of many plants, and particularly that of robi*
nia altagana is combined with wax, although the leaves have not
the shining appearance usually given by wax.
, Indigo grown in the open ground at Paris yielded the same re-
fults.
Observationtj'^heae experiments are a part of the immense
SUFFL.— TOL. Vir 3 U
sot * On Muriatic Add and Oxymur'}^%c Acid.
researches undertaken by the agents of tke French govemmeot
in order to do without foi;eigti commeree. The cultivation
of the indigo plant in the open ground, is important, and if th«
experiment continues to proceed, it may lead to serious conse>«
quenees to the indigo growers in the West Indies.
On Muriatic Acid, and Oxymuriatic Acid. By Messrs. Thenaad,
aA(/GAr.LussAC. Journ, des Mines, No, 145.
This memoir is very long, and the following are the principal
results obtained by them.
1°. Muriatic acid gas contains one fourth of its weight of water,
and there exists in thi§ quantity sufficient oxygen to oxidize at
inuch metal as the acid can dissolve.
^^. Oxyniuriatic acid gas weighs 2-47times as much as an
equal bulk of air. It contains half its bulk of oxygen gas, and
all the water which it can form with hydrogen is retained by the
muriatic acid gas which it contains. If the quantity of water is
calculated, it will be found to be precisely one fourth of the
weight of the muriatic acid.
5^. Dry oxymuriatic acid gas by combining with metallic sul-
phurets forms muriates, and the new substance discovered bj
Thomson.
4^. This gas cannot be decomposed by dry sulphites, but it is
immediately, if they are slightly moist.
5°. Oxymuriatic acid gas is not decomposed by charcoal at a
very high red heat, and it is only by means of the hydrogen re-
tained by charcoal that it can be converted into muriatic acid gas,
6°, Charcoal, and even plumbago, although strongly calcined,
still Contained a little hydrogen.
7^ Common muriatic acid gas undergoes no alteration by be-
ing passed over red hot charcoal.
$^. Sulphurous acid gas, gaseous oxide of carbone, gaseous ox-
ide of azote, nor even nitrous gas, if they are dry, do not decom.
pose oxymuriatic acid gas : but by the help of water they decom-
pose it immediately.
9^. Oxymuriatic acid gas is decomposed by water alone, at a
temperature a little below ignition.
10. A mixture of equal bulk of oxymuriatic acid gas and hy-
drogen takes fire at the temperature of 125°.
. 11°. Whenever light acts upon inorganic bodies, and is absorbed
by them, it produces the same effects as heat.
li° In a great number of cases in which two gases mixed to-
gether have been found to combine iflowly, as oxymuriatic acid
gas and hydrogen; it is light that is the cause of their combi-
nation. As it only penetrates, by successive portions into
the gaseous mixture^ and only by a very small mass at a
On /it Cambmaiion of Gaseous Bodies xtnih one another. 503
time its effects are' successive, but so much the more speedy,
as the light is more intense ; in complete darkness no conobina.
tion takes place.
13°.\ Hydrogen, mixed with an equal bulk of oxy muriatic acid
gas, takes iife and detonates immediately on being exposed to the
direct rays of the sun. The case is the same with olefiant gas,
14^. Oxymuriatic acid gas cannot be decomposed, unless by
metals with which it forms mgriates, or by water and heat, by
which common muriatic acid gas is reproduced, or by hydrogen
mufi substances that contain it. In all other cases, in which
water that can combine with the muriatic acid gas is not formed,
oxymuriatic acid gas is not decomposed.
15^. Carbone does not decompose muriate of silver, at any de»
gree of heat hitherto tried ; but when it contains hydrogen, the
muriate is decomposed.
l6^ A mixture* of carbone and muriate of silver, which can.
jiot be decomposed by heat, is immediately deoSmposed if steam
be passed over it.
17"« The muriates of silver, of barytes, and of soda, are not
decomposed by vitrified boracic acid at a very high temperature ;
but as soon as 6team is passed over the mixtures of the muriates
and boracic acid, the muriatic acid is completely separated.
18^. Muriate of 8uda, (common sail) is decomposed by
saud and alumine at a red heat, by means of water ; and the case
h the same with almost all the muriates. a
19*» Muriatic acid gas cannot be obtained devoid of water^ for
that liquid is essential to its gaseous state.
Observations, '^The originaj memoir has not 'yet come to our
hands, but as the paper is important on account of the novelties
in the theory of muriatic and oxymuriatic acid, which Mr. Davy
has promulgated in his last Bakertan lecture, of which an account
was given in our last number, p. 426. we have thought proper to
give our readers a ,trafislation of the abstract given in the Jour«>
nal des Mines, The hypothesis of Thenard and his coadjutor
is diametically opposite to that of Mr. Davy, but the former hy-
pothesis is still capable of being defenG^d as is well observed by
Murray in his Elements of -Chemistry just published.
J ,
On the Combination of Gaseous Bodies with one another. By Mr.
Gat-Lussac. — Nouv. Bulktin des Sciences^ and Uoum. des
Mines f No, 145.
Gases combine only in very simple proportions of their volume,
thus in making experiments along* with Mr. Humboldt, on the
analysis of . atmospheric air, it was found that 100 parts of
•xygeji exactly saturate 200 of hydrogen, so that the proportion
504 On the'Comitnaim o/GoKom BvtUa with o^e aitotker.
of these two gases is as 1 to 2. Fluoric acid gas, prepare^ bf
decomposing fluate of lime by vitreous boracic acid, muriatic
acid gas aud carbonic acid gas being mixed with amuiosiacaf gas,
it was fouud that the two, former acid gases combiriiBd Urith an
equal volume of alkaline gas and formed' neutral salts, but the
carbonic absorbed twice its volume and formed a sub*. carbonate,
80 that it it. probable tha( had the acid been saturated it would
have coml^ined with its own bulk of aromoniacal g^s. And it
seems fis if all theacjds, provided they were brought to a gaseous
state, would saturate an equal volume of ammoniacal gas or any
other alkali in a gaseous fornfi. It would then be easy to cak
^ulate the capacities of the acids^ for they would be in the inversa
r^tio of the densitie4 of the gases.
According to Amadeus Berthollet, ammonia is comppsed of
' 100 parts in bulk of azote, and ^00 of hydrogen.
When sulphuric acid or . alum is decomposed by he$^t, 3 parts
io bulk of sulpurcnis acid gas, and 1 of oxygen is obtained ; which
represents the proportion of the elements of sulphuric- acid.
. too parts of gaseous oxide of carbone obtained from oxide of
zinc and charcoal, fired with IQO of ojr^en, form 2P0 of cart
booic acid gas.
By reducing the analysq^ given by Mr. Davy, of th« various
/combinations of azote with oxygen by weight into bulk ; gaseous
oxide of azote^is composed of lOQ parts in bulk of asofte^ witb
49*6 of oxygen; nitrous gas of 100 pf azote with lOd'4) of
oxygen ; and nitric acid of 100 azote with 204.7 of oxygca. Oa
analysing,, however, nitrous gas by meana of potassium, it was to
'be composed of exactly equal bulks of oxygen and azote, and in
like manner gaseous oxide of azote must be composed of 100
azote with 50 oxygen, and nitric acid of 100 azote witl^ 200
oxygen. ^
Oxyrauriatic acid is composed, according to Cheo^vir, of 77''$
parts in weight of muriatic gas and 22*5 of oxygen, which being
' reduced into bulk, according to Kirwan's estimate of their specific
gravity, gives 100 parts in bulk of muriatic acid gas and 49*5
of- o5cy^en ; the latter may be corrected to 50 partvt
From the above it appears, that when oxygen combines with
other gases, the proportion by bulk is as Ir^to 1, 1 ta 2, or 2 to 1 ;
biU if two CQUibustible bgdies combine togetboy a& aaota and
hydrogen in forming ammonia^* the proportion is 1 to 3. Whep
the proportions are taken by weight, this simplicity of the ratio
^ Wt observed, so that it seems peculiar to elastic fluids, 4nd
shews that it is not a matter of indifference whether the propor-
tions of the gasses that enter into a combinatio^i of tbem ape;,
estimated by the bulk or the weight.
The apparent contractions that gases sufier when they enter
into com^inftioii are abo in a very simple proporiion to tkf ca^.
•
t)n the Comhimtitn of Gaseous Bodies with one another* SOB
gi«al bulk of the whole, or at least of one of them Thus 50 parts
jn bulk of oxygen and 100 of gaseous oxide of carbooe\ form 100
of carbonic acid gas ; of course, the apparent contraction was 50-
parts, OF the whole bulk of the oxygen. By this experimeiit the
specific gravity of gaseous oxide of catbone, should be equal to
that of carbonic acid gas subtracting the weight of the oxygen
that was added, or to air^ as I to 1*054* Cruik shanks states it at
1^045; It is known already that oxygen produces' an equal bulk
of carbonic acid gaS| wherefore oxygen in forming gaseous oxide .
of carbone must double its bulk, and caj*bonic acid gas passin|r
oy^r red hot charcoal must be doubled in bulk.
Sulphuric acid is stated to be composed of 100 parts of sul*
phur, and 138 of oxygen by weight, or of 100 parts in. bulk of
silphurous acid gas and 5Q of oxygen, so that oxygen must also
preduce an equal bulk of sulphurous acid gas, and the whole bulk
of the valour of sulphur is apparently lost, and sulphurous acid
must be composed of 100 parts ia weight of sulphur. and 9^ of
oxygen. ,
In like inanner the density of oxymuriatic acid gas is to that
of air, as 2'47 to 1 ; a!hd if to the density of muriatic acid gas,
the half density of oxygen is added (as oxymuriatic acid g^ con*
tains 100 p-cuts in bulk of the former, and 50 of the latter,)
the calculated density would be 2*48 : whence it appears that the.,
contraction is equal to the eatire bulk of the axygen.
In gaseous oxide of azote^there is also a contraction equal to
the whole volume of the oxygen ; but in^nitrous gas there is no
contraction, for the density as^ calculated, is equal to that found
by experiment*
If the contraction occurring in the formation of ammonia is
estimated at one half of the whole bulk of the component gases^
Qr at twice the bulk x>f the azote, its calculated density ;i¥ould be
0*594 ; . the density by experiment is 0*5961
If the contraction occurring in the formation of water is esti»>
mated at the whole hulk of the oxygen, the density of the water
formed, supposing it in an elastic state, i. ei as steam, would be
to air as 10 to l6, or 1700*6 times the bulk of tjie fluid water
into which it would condense, which nearly agrees witlx the state-
ment of Watt. The refraction of moist air, calculated accord-
ing to this density of watery vapour agrees better than before with
that actu^ly observed.,
It liiust be remarked that the apparent contraction is not con.
necjtedr witb^ the real force with which the elements combine ; for
there are several cases in which the elements combine very strong*
ly although the apparent contmctioa ia insensitxlie, and even others
in which a dilation takes place.
Pffservatum.'^Tht original memoir, of which this b an ah*
506 Chronoiogiial last ofMeteor$f SfC,
ttract has not come to our hands, but as the subject is veiy cti-
rious, we have thought it necessary to give our readers some
account of it from the Journal des Mines.
Chrmological list of the Meteors y iokick have been ^mcceeded By fke
/all of Sionet or masses of Iron.^-By, Dr* E. F. F. Chladni.
Journal des MmeSy No* \4iS*
Biot has shewn that the Mater deomnij brought from Phrygia
lo Rome in the time of Scipio^ Nasicav was a meteorolite : as are
also the masses of iron containing nickel found in different
countries :
Viz* In Siberia, by Pallas.
In Senegal.
AtSaint Y'ago, in Tucuman.
In Peru.
At Toluca, in Mexico. '
And at the Cape of Good Hope.
644 before Christ. Five stones fell in the province of Song
in China, antient Chi'nese historians, as mentioned by De Guignes.
Voy. ^ P6k. t. 1.
462. A large stone near Aegospbtamos. Plutarch, in Lysan-
Apo and Pliny. H. N. II. 58.
211. A stone in China. De Guignes, ut Sup.
192. A stone in China. Ibid.
89. Two stones at Yong in China, the noise was heard at 40
leagues distance, and the Bky was serene* Ibid.
About 56. A spongy mass of iron in Lucania. Plin. H. N. II.
56, who says he has seen a stone that fell in Agro Vocontiorun^^
!• e. near Vaiscen. II. 5S«
38. Six stones in the province of Leang, De Guignes, ut Sup.
29. Four stones at Po, and two in the territory of Tschin^ '
ting fort. Ibid.
22, Eight stones. Ibid.
19, Three stones. Ibid. .
12. A store at Tou kou an, Ibid.
9. Two stones. Ibid.
6, Six stones in the province of Ning tschou, and two at Yon.
452 after Christ. Three large stones in Thrace. Amroian.
Marcel. Chron.
In the time of Pope John XIIL 9^4 to 970. A stone in Italy
Plat, in Vit. Pont. '
Avicenna, who was born in 9S^> mentions a mass of very hard
iron weighing 50lb. that fell at Lurgea, Lorge.
998. Two large stones, at Magdebourg. Span^i* Chron. Saxon.
Cht^nologkal List of Meteors^ 8fC. 507
1 136* A istone the size of a man's head, at Oldisleben in Thu.*
ringia. Ibid.
1 164. On Whitsunday. A shower of iron in Misnia^ Geo.
Fabric. Rer. Misn. 1.32.
1 249. On St. Ann's day. Several stones, in the neighbour*
bood of Quedlinburg, Ballenstadt, and Blackenburg.
1304. On St. Remits day. A number of stones which caused
, great damages near Friedland in Vandalia. Kranz. Sax. &c, at
Friedberg, near Saale. Spandeiib.
1438. Spongy stenes near Koa,^not far from Burgos in Spain,
Poust.
1492. Nov. 4. A large stone, at Ensishaim in Alsace, well
known.
1510. A large shower of stones, near Crema, not from the
River Adda in Italy, Card. Var. 14. 72. Bodini, Theat, Nat. II.
First half of that century. A large mass of iron, in, a forest
near Neuhoff between Leipzig. Albinus M«isn, Bergchron. 139.
1548. Nov. 6. ' A blackish mass, at Mansfield in Thurin^ia.
Spanderb. ut Supra.
15.52. May 1 9. A shower of stones, which did great damage
in the neighbourhood of Schleu&ingen in Thuringia. Spanderberg,
at Supza. who carried some of these stones to ^isleben.
1559. Five stones of masses of iron, near Miskoz in TransyU
Vania. Isthuansiu«. Hist. Hung. xx. 394.
1564. March 1. A shower of stones, between Brussels and
Malint'S. Ann de Gilbert xxii. 3.
1581. July 26. A mass weighing 39lb. in Thuringia. Bin^
hard Chron. Thut. 193. .
1585. A stone weighing 3Qlb. in Italy. Fran. Imperati.
1591* June 9* Large stones, near Kunersdorf. Angeius Ann«
Marc bid.
X603« A stone that contained metallic veins, in Valencia in
Spain. Jesuits of Coimbra on Arist. Meteor.
1617. Nov. 27. A stone weighing 59lb. upon the Mountain
Vaisien in Provence. Gassendi.
1635 June 21- A large stone, at Vago in Italy i Fr. Carli.
1636. Mar. 6. A large stone, between Sagan and Dubrow^
in Silesia. Lucas Chr. Siles. p. 2228 CJav. Geog. 233.
1647* Several stones, in the BailiwicK of Stolzenan in West.
phalia. Ann. Gilh. xxix. 2. ^
l650- Aug. 6. A stone, at Dordrecht. Arn. Senguerd. £xer.
Phys. 188.
l652. A mass r)f iron weighing 5lb. near Labor in Hindostanw'
Journ. dc Phys. Germ. Ann, II.
1654. Mar. 3. A shower of stones, in the Island of Funen,
in Denmark. Barth. Hist. mot. Cent. iv. 337«
16^7. Several stones, at ISchirasj in Persia. Pere Ange d<
508 Cironologkal Hit of Metehrs^ ifC*
St. Joseph* Gar. Ling* Pers. The account is accompanied witfr
circumstances scarcely probable.
1672. Two stones, one SOOlfar. the other 3001b. near Verona.
Lt Galois. Conv. Paris, l67t« Obs. 5.
1674. Oct. 6. Two large stones, in the canton >ofGlani8 in
Switzerland. Scheuchzer.
1677 • May 28. Several masses, near Ermendorf, not far
from Grossenhayn in Saxony. Balduinus in Mise. Nat. Cur.
1697. App. 247. According to bis analysis, they seem to have
contained copper.
1683. Jan. \i, A mass of stone, or iron, near Castrovillarii
in Calabria. Mercator Met. Vatic. 19,S48.
■ Mar. 3. A stone, in Piedmont. Idem.
1698. A stone, in the cantoli of Berne. Scheuzer Naturges^
der Schweitz. ii. ad Ann. 1706^ p. 75.
.1706. A stone of J2lb. uear Larissa in Greece. Paul Lucas^
Voy. I.
1723. June Sd. A shower of stones, sbar Plescowitz ia
Bohemia. Stepling de Pluv. Cap. 1764.
1743. Several stones, near Liboschitz in Bohemia. Idem.
1750. On St. Peter's day. A large- stone, near Nicor \tk
Normandy. Lalande. Joufn. de Phys.
1761. May 26. ' A mass of iron, weighing 7Ilb. and another
weighing l6lb, unmixed with stoney matter. Stutz. Joum«
Bergbauk, t. 1. The largest mass is preserved in the Imperial
Cabinet at Vienna. Klaproth found this iron to contain nickeL
1753. July 3. A shower of stones, near Tabor in Bohemia.
Stepling and others.
■ ■ ■■ Sept. Two stones near Lfiponas in Brescia. Lalandie
Journ. de Phys. Iv. 451.
1766. Middle of July. A stone, at Alboreto, near Modeno.
Troili Rag. della caduta di Mn Sosso VassaiU. Lett. fis. meteor,
p. 120.
Aug. 15. A stone, near Novellara. Perhaps the same
meteor as tbe last, in which the month may have been errone.
ously stated.
1768. Sept. I?. A stone weighing 7lb. and a half, near Luce
in Maine ^ another near Aire in Artois ; and a third in Cotentin ;
all from the same meteor. Mem^ de I'Acad. de Paris.
, ■ Nov. 20. A stone weighing 381b, near Maurkirchen
in Bavari, preserved in the Academical Cabinet at Munich. Aa
analysis of it, by Imhoff, is in Voigt Mag. vii. 3, and in Ann de
ipilbert.
1773. Nov. 17* A atone, near Sigena in Arragon. Proust.
1775. Sept 19. A stone, near Rodach iif Cobourg, preserved
in the Cabinet at Cobourg. Ann. de Gilbert, xxiii. 1.
1779. Several stones, at Peterswood in Ireland. Gent Mag*
Sept. 1796.
Chronological list of meteors^ Spc. 50f
1J85. Feb. 19. Several stones, in Eichstaedt. Moll, Annal.
.12,1.
1790. July 24.
Hac, &C.
17^4. June 16.
1795. Dec. 13.
in Yorkshire.
1796. Feb. 19.
A large shower of stones, at Barbotan, Ju«
Many stones, nenr Sienna
A stone weighiug 661b. near Wold Cottage
A stone in Portugal. Southey, Voyage.
1798. March 17* A stone weighing 201b. at Ville FraDchc
in dep. of the Rhone. LeLere, Dree, &c.
A stone that fell near Bialoczerkiew, nnentioiied by Hortum,
in Voigt. Mag. VIII, 1, with neither year, nor day.
Dec. 19* Several stones, at Benares in Bengal..
1803. April 26. A large shower of atones, in the neigb<«
bourhood of L'Higle, Dep. of the Orne.
Oct. 8. A stone wei^^bing 7lb. near Apt in Provence.
Dec. 13. A stone weighing 3lb. and a quarter, not far
from Eggentelde in^-Bavaria: analysed by. Imhof, Voigt, Mag*
and Ann. de Gilbert.
1804. April 5. A stone near Glasgpw in Scotland. Ana.
de Gilbert, XXIV, 369-
1805 March 15. A stogie, near Doroninsk, not far from
the riVer Induga, Gov. of Irkutsk in Siberia. ,
June. Several stones, at Constantinople. Jonrn. des
Mineb. Feb. 1808, 142.
1806. March 15. Seyeral stones which contained charcoal^
near Alais and Valence, in Dep. of the Gard.
1807. June 27. A stone weighing l6olb. near Timochin,
in Gov. of Smolensk in Russia.
Dec. 14. Many stojies at Connecticut in America.
1808. April 19. Several stones^, near Pieve de Casignauo,
in Dep, of the Taro.
May 22, Many stones, near Stannern ia Moravia.
Sept. Several stoiies, near Lissa in Bohemia, accorcRng
to the German newspapers.
Obsertations.'-^A detailed account of some of the last mention*'
ed meteors, and an examination of the stones that fell, may be
found in the former volumes of- this work. The present list is
the most complete that has yet appeared, and seems drawn op
with great care.
SUPPL.— VOL. vx. 3 X
:•'»
410
On PcMlende^ an Ore of Uranium.""'^ By Mr. VAUQUEtlir.
Annalis de ChimU, Vol, '68.
Mr. de Laiinoy possesses several specimens of a black, brilliant,
compact heavy mineral, having a conchoid fracture which Hauy
could not determine whether it were gado Unite or pec h blende ; but
upon sabmitiing it to an analysis, it was sdon Ibund to be of the
latter kind.
. The analysis itseK is curious by its exhibiting the state in
which uranium is found in the ore, and the combinations* It is sus-
ceptible of forming with oxygen.
- Pechblftnde in powder is soluble in muriatic acid of a middling
strength without any efFerrescence, . but the smell of sulphuretted
hydrogen gas is perceptible. Tb^ solution is very deep ilbscure
gneen, and on being diluted with water and filtered it left a little
fiitica and' sulphur. On evaporation and cooling, cr)'stals of mu.
riate oi lead were deposited, which were separated by adding aU
kobbl t^ take Qp. the muriate of uranium without dissolving the
muriate of lead : th^s alkohol was afterwards got rid of by heat,
and the solution diluted with water.
Muriate of uranium is precipitated by caustic ^kalies and their
est bonaleS' of a deep bottle green, which becomes black and bril-
liant on drying, particularly that formed by^ ammonia. Prussiate
of potash produces a dark chocolate precipitate ; infusion of gall-
nuts produces a greenish-brow» sediment which changes to yellow*
ish red in- the upper part.
The precipitate formed by ammonia,, although it hrf» dried in the
air, yielde water and ammonia on distillation, and becomes of a
poach deeper black. Tbe dried precipitate was soluble in cold di-
lute nitric acid forming a green solution which^on being heated
emitted naucli nitrous vapours and changed to orange yellow,
Thesolution of this calcined axide hi nitric acid, being diluted,
deposited, in time, some oxide of iron ; so.that this one contained
a little lead, iron, sulphur, and silica, and appeared to be the
variety analysed by Klaproth under the name of Joachimst&al
pechblende.
This last solution of oxide of uranium in nitric acid is precipi-
tated orange yellow by pure alkalies, and pale yellow by the alka-
line carbona.tes ; an excess of the carbonates redissolves the preci"
pitate. Prussiate of potash and infusion of gallnuts yield brown
red precipitates much paler than before.
Green oxide of uranium added to liquid oxyqiuriatic acid takes
away its smell and the solution assumes a yellow colour. Green
oxide of uranium yields yellowish green crystals with sulphuric,
Bitric, muriatic, andacetic acids : the yellow oxide does not form
J Description iff Dichroke. 511
perfectly neutral salts, nor do they crystalise. The gre^n oxide
does not dissolve in th4 aBStfttfle-^aybonates, but the yellow oxide
b very soluble in them.
Uranium therefore forms two oxides, one dark green, the oth^
orange. The yellow ore of u»anium Ibund by Champeux in the
neighbourhood of Autun, in Upper Sa6ne, contains the yellow
oxide ; and pecbblende the green as it emits no gas on solution
in muriatic acid. It is doubtful whether the sulphur in pech-»
blende is combined with the oxide as its quantity is so small, it
seems rather to be united with the lead. Klaproth did not con-
sider pechblende as a sulphuret, but as uranium very slightly oxi-
dised, which' he deduced from its yielding nitrous gas on beiilg
dissolved in nitric acid.
These two oxides resemble those of iron in their habits with
acids and alkalieS ; as green oxide of iron neutralises acids, forms
crystallisable salts with them,, and does not dissolve in alkalies;
and red oxide does not neutralise acids, forms uncrystallisable
salts with them, and is soluble in concentrated alkaline subcarbo-
nates.
The. oxides of uraniumjseem also, from the preceeding experi-
ments, to combine with water, and iform hydrates.
Observations^ — ^These experiments evidently shew that uranium
forms two different oxide.f, a fact which Klaproth had not indi-
cated in his examination of pechbende.
On the Benzoic ' Acid cimta'med in the Urine of herbrcorovs animah
By Mr, Vauquelin. — Amales de Chimie, Vot. 69.
On the first discovery of benzoic acid in the urine of herbivo-
rous animals,. Messrs. Fourcroy and Vauquelin announced that it
might be extracted with advantage on account of the largeness of
the proportion..
Since that time a kind of benzoic acid has been introduced into
the shops, of the san*e appearance of that formerly used, not only
destitute of the finje aromatic smell, but actually possessing the'
peculiar odour of the urine of herbivorous animals. If this
smell could be re^ioved, and that of benzoin substituted, it is
evident that it might be used for the same purposes as the old
flowers of benjamin; and this is easily performed by subliming it
afresh, witl^ the'addition of about one tenth ol powd^iied benzoin.
The qjuantity of benzoic acid obtainable from this onne varies
a little, but upon the average it may be stated at l-3C0th pait.
Several other j^eful substances may be extracted from this urine,
as will be mentioned in a future essay.
5lt
•*mmm
Descripfwn of Dichroiie, a new Species of Minerah, B^ Mr,
L(iuis Cor DIE II. Journ, det Mines, No, 146.
This mineral belongs to the class of earths and stones, and
ought \o be placed next to the emerald. It has been long knoLWO
in the neighbourhood of the Cape de Gattes, in Spain, and to the
lapidaries at Carthagena. Reuss says that Werner considers it
as a distinct species under the name of Yolithe, .places it next to
cat's eye, and divides it into thiee varieties, glassy, porpbyritic,
and common. Karsteu hab placed it in his tables between lazu-
lite and the andalusite of Delametherie. Jt is not mentioned by
Delanietherie, Hauy, Patrin, Brongniart, Lucas, or in any Frenck
XTork yet published.
Dichroite is found in large shapeless or cr}fstallised grains,
which are sometimes separate and sometimes grouped together in
masses of a small i>ize, less than ,a deciitietre (4 inches). Its
specific gravity is 2' 56*0. It scratches glass deeply, and quartz
weakly ; it is easy to break, the fracture is glassy, snfBcientlj
shining, and frequently exhibits traces of very visible plates.
The fragments are irregular with sharp e^ges, the powder very
rough to the touch. Externally it is <;ommonly tarnished. The
translucid crystals have a peculiar property which may be called
a double colour by refraction. Their primitive form is a regular
hexaedr&l piusm; the integrant molecule is a triangular prism, the
bases of which are rectangular scalene triangles. It is divisible
parallel to the faces of the hexaedral prism, and is susceptible of
being subdivided by longitudinal ciits perpendicular to the lateral
faces. It is not altered by acids, and is difficultly melted by the
blowpipe into a very pale greenish gray enamel. The same result
is obtained with either the borate or carbonate of soda. It is not
electric by heat. It is sometimes opake. All the grains or cry-
stals are violet by reflexion, (from which Werner gave it the
name of yolithe, i. e. violet-stone) this colour is usually the
least lively in the longitudinal direction of the pHsms. All the
translucid grains or crystals appear of a very dark blue when they
are viewed parallel to the axis of the prismsj and of a very pale
brownish yellow, as well as six times as transparent when ▼iewed
perpendicularly to the axis.
It is lound in two places of the Cape de Gattes, viz. at Grana*
tlUo near Nijar, and at the foot of the mountains which surround
the bay of ban Pedro. At the latter they are found m an im.
mense hcrizontal bed of volcanic breccia, composed principally
of fragments and blocks of black or red sconaei, and of black
glassy or lithoid lava, both basaltic and petrosiliceous. '' The di-
Descripilon of Dickroiic. ii^
ctiroite is usually impasted in the blockis of the last ; it is also
1)01 only found in the gray or whitish tuff which forms the basis
of the breccia, but also ih some fragments of foliated granite that
it contains. These fragments have evidently been acted upon by
heat, and the bed from which they were detached is probably the
original seat of the dichroite. This granite -contains plates of
black mica, and trapezoidal red garnets like those found in the
aggregated masses of dichroite and even in the interior of its
crystals, which shews it to be cotemporaneous with the granite.
The petrosiliceous lava in which dichroite is most usually found
is granular rather than compact, and formed of very fine grains o^
felspar,, like that of the Puy de Dome, the cascade of the Mont
d*Or, and the Lipari islands. The fire has left its marks on th#
dichroite itself ; most ef the masses are corroded as it were in
differei^t places, internally as well as externally, and shew in the
cavities, parcels of white scoriae both unaltered or decomposed.
Most ef the crystals are fritted, and full of cracks ; the fragmeote
have frequently their surfaces covered with a very thin whitish
crust, which hides the brilliancy of the fri^cture.
The name yolithe, is improper, and liable to be confounded
with hyalite, or concreted quart, and with yanolithe oryonolithep
the name given by JDelametherie to' violet schorl.
It is not known whether dichroite doubles images seen through
it, as the crystals hitherto found are not sufficiently transparent :
if it did, as this phenomenon could only be obBerved in a <firectiom
oblique to the axis of the prism, the single images would be seen
of both the colours separately, according to the position in which
the crystal was viewed, and the images would be doubled in tht
direction in which the colours were seen mixed together*
This phenomenon of a double colour is very curious. The tinc-
ture of nephritic wood appears blue by reflexion, and yellow when
it is looked through ; ^old in very thin leaves transmits a green^
ish colour ; but the colours of dichroite are more complicated.
Observatiojis, — This stone is certainly one of the most curious
minerals, hitherto discovered, in respect to its habits with light ;
in pthcr respects it does not differ much from other volcanic gems«
8YP?L. vox,. VI. 5 Y
• ^
tRliAtA.
F«r pages 341—^^, tlie second set, being sheet 9 i, read 349— Sftil
N. B. f he Indek quotes the proper nvmbets.
By an emor in prioiuig, the pagio^ skips iiadk 436 to 4571
INDEX
TO
VOL. VI.
s=»
i A.
AcRTATt of ammonia^ oh prepar-
ing, 24Z
Acid,' on the acetic, 271 ; on the ar-
tificial saccinicy 213 ; oa the ele-
ments of the mnriatic, 426; on
. the 02Lymgriatic, 426 ; on the
uric, 237 ; on muriatic and oxy-
muriatiCy 510; on benzoic, 519
Acids, on the capacity of the metals
, for saturating theni, no; on
violet pickle as a test for them,
Aconitum napellus, iot
Albumen, on its coagulaeiiota, 241
Algebra, demonstration of the Cotc-
sian theorem, 45
JUkalies, /on the metals obtainable
from them, 95 ; on action of phos-
phorus and oxymuriatic acid upon
them, 97 ; on metallizing without
iron, 106 ; apparatus for decom-
posing, 206 ; on those prepared
with alkohol, 460
Alkalijie metals, experiments on,
x8o, 183, 187 ; on Gay-Lussac
and Thenard's observations on
them, 436, 498
"Aloes, examination of, 257, 259, 421
Ammonia, on its composition, 213 ;
on amalgam of, 433
Amos, Williaffly on ploughs, break-
ing ^ttle^ whe^-carriagcf, &c.
157
Animal food, on loss of weight Ul
cooking, 283
Anthropo-telegraph, 4a
Apophyllite, 181 .
Archbold, John Frederick, patent fox
making fresh water from sea water,
167
Arragonite, 177
Asclrpias, on the Syrian, loz
Astronomical instruments, on di*^
viding, 1 1 ; on examining the di«-.
visions of, 1 3
Augite, 229
Azimuthal refraction, 127
B.
Bacon, A. on Swedish turnips, 3^4 .
Balls, on their penetration, 487
Banks, Sir Joseph, on Merino sheep,
285 ; on seed grain, 296 ; on the
cultivation of the Spanish ches-
nut tree, 463; on the forcing-
houses of the Romans, 467
Barclay, David, on oxen, 296
Barley, on its use for horses, 288 ;
on naked, 289; on Grecian, 290 ;
on French and Swedish, 366
Barlow, P. demonstration of the
Cotesian theorem, 45; on trans-
forming a number from one scale to
another, 51 ; a curious muucricai
proposition, 578
3»
INDEX.
fiarometer, on its use in predicting
the weather,^ 390, 394; on the
new mountain, 485
Barron, ^ohn^ patent window-blinds^
Barton, John, patent lamp, 70
Batcbelor, on broad-<:ast and drill
husbandry, 301 ; on smut in
wheat, 369
Bate, B. on the camera lucida, 60
Beal, D. on the culture of early
purple brocoli, 461
Bean-stalks, 299 .
Berard, E. on muriate of tin, z#9
Beril, on schorlous, 229 ' '
BerroUas, Joseph Anthony, patent
warning watch, 414
Berthollet, Junior, on the composi-
tion of ammonia, 213
Berthollet, Claude Louis, on Chene-
vix's and Descostils' experiments
upon platina, 194
Birkbeck, Morris, on sheep, 233
Blanchard, J* raia that fell ia ido^a
Bolton, Captain Willitm, liftVal itti-
provements, 33'
Bostock, Dr. John, Oft xnereorology,
132 ; on meteorological nomeo-
claturt, 313
Boswill, John Whitley^ on wheel-
carriages, roads, harness, &c. 595
Bouitlon-lAgrange and Vogel, on
aloes, 421
Bouvard, tat)te of the tidfes (bri'811,
389
Biaconnotj Heniy, on gtun ivsilis,
Bradbury, John Leigh, patent for
spinning, €6
Bnuiley, EichatS RamsdeD,^ on
draining, 365 »
Bftsil wood, S8
Brcwerton, T. Le CJay, cm Wi acid
froth gingar, 216
tecwing, Dc Rochet patent for, i«6
Brid^eS) on OOhstroctitig woodcfn, 316
Brightky, James, on long dung, 367
firinkley, Kefv. Dt. on the annual
^wrauftx of lyrae, 476
Brocoli, early purple, onltso^ture,
461
Biockbank, J. machine fbr making
slate pencils, 27
trunel. Marc I^ambard, patent mt-
chine for cutting veneers, 1 60
SochoU, anvils 6i pyritts, zyU
Building, Grove*9 patent for, 544
Burckhardt, J. C. on the theory of
comets, 3 22 ; on observing the sun,
387
Burr-knot apple, on its culture, 46 s
C.
Cabbages, on drumheaded, 298
Cadet, C. J. on tea, 189
Camera lucida, (o -
<7amphor, on Cadet's aqueous soliu
tion of, •213 >
Carriages, Le Caan's patent for checks
Carfofs, on their culture, 83
Cartwright, Rev. Dr. on fattening
sheep with muacovadc^sugar, ^6
Castelcicala, Prince of, on Sicilian
wheat* 286
Cattle, on the use of- heath in feed-
ing, 294; on the Highland ma*
nagement of, 302; cm the black
spald in, 306 ; on feeding, 365' ^
on polled, 367
Cavendish, Henry, on dividing aur
tionomical instruments, 1 1
Gayley, Sir George, on aerial navi{^
tion, 21
Ceylonite, 248 -
Ct&bosie^ 1^7
Charcoal, on the manufkctare of, 11^
close vessels, xoo
Chenevijc, da his exp^ments t^po*
platfna, 1 94
Chesnut-cree, Spahishy oa t!^ cttfti-
Tation, 4^3'
Chevreul, on brasil and log wood, 88;
on indigo and woad, xoy ; 011
urine, and the orfc add'inblrd^
^^^^Si 237; on the itrdtgo «nd
woad plants, 50^
Chimi, Wkrbunofi's patent ftJr &tta»
mirig,^i69
Chip botes, GodtdardTs patent for
making, 345
Chtadtti, Dr. on tl^tneteoric^ntSB
Chopping machihe, 26
Cbtononfeter, Schmidts psitekb
phantasmagoric, 164
Chirke, Dr. meteorologlcia table for
1809, 125
CfitikstoTie, on nodutei cf l&tiL Hi^
49
Clock escfpenftffit, 151
Cocl Wines, oii cmmttrae^li^ "fU^
gases found in^ 49
JiXiMyJaX»
^dchnaCy Major S^peooer, on Hint,
235
Coke, T. W: on long dung, 292
Coloured rings, on Herscber^ theory
of them, 380 *
Comets, on their theory, 322 ; new
theory on their orbits, 4S6
Congreve, William, on planting oaks,
300 ; patent tei Aecurtng houses
against fire, 353
Cook, B. on constructing theatres,
145 '
Copper ore, analysis of one, 1 14
Cordier, Louis, on dusodile, i78|;
on dichroite, i^ao
Cotfe on the diminution of dilatabi-
Itty of alkohol by age, 244
Coutelle on Rospini's lens, 17
Cow, produce of one, 459
€hiige, John, patent kitchen fire>
place, 348
Cramp, Mr. pnxlnce of his covr,
450
<?rane, Mr., new theory oh the orbits
' of comets, 486
Crocuses^ on their cultivation, 458
■Crops, on^weedingy 364 ; on courses '
of, 3<55
'Cumberland, G. on stone-ware files,
149 ; on preserving lives in ship-
wrecks, 409
Cujiping instrument, i^
C^odau, F. R. on melalltsing th^
alkalies without iron, 106; on the
■ alkaline metals, 187; on the de-
composition of sulphuf) 191, 243 ;
oh his experiments npoii sulphur,
198; on his paper upon stilis,
" lio ; on sulphate of alumine, and
some salts of potash, 246 { on
Vauquelin and Berthollet's report
on his paper, 25<^ ; Deycux's re-
port on his paper upon phosphorus,
iron, lime, &e. 273
Curwen, John C. on planting larch*
trtes, 370
Cutbbertson, John, on eleotrioal ma-
chines, 3 20 ; on Wingfield's me-
t^iod of Increasing the charging
capacities of jars^ 378
/ChTter and Brongnart, min^ralogkal
geography of Paris, 200
Cystic oxyde, 424
Of
pahlias, on its culture} 4^0
99t<Hite| ^44
Davy, Humphry, on the new metals
and on some combinations of hy-
drogen, 216; op. oxy muriatic
acids,. &c. 426 ; on Gay-Lussac
and Thenard's researches on the
amalgam of ammonia, 433 ; oa
their observations on the alkaline
metals, 436 ; reply to their answef
on the same subject, 498
Daubuisson on iron ores, 464
D'Arcet on potash and soda prq^
pared by means of alkohpl, 460
De Dree on the forination. of Uthoid
lava« 171
D'Halloy, J. J. Omalius, on flint
slate- formation, 182
De Heine, Aug* Fred, patent presses,
161
De la Roche on the air-bladdeis
of fishes, ,120 ^
•De Roche, Randolph Tscbiifcli» p.a*
tent for brewing, 166
^ Derosne on formation of acetic ether
in grape cake, 462
Descostils, on his experiments upon
pla^ina, 194
Descroizilles the elder, on a test for
acids, and the distillation of plants,
193
De Serres, Marcel, on printing upon
stone, 138; on ceylonite, 24^
Desmortiers, JLe Bavier, on pneu-
matic tinder-boxes, 251
]>estouches on preparing acetate 9f
ammonia, 2^2
Deyeux on Cuiaudau's memoir on
phosphorus, &c. 273
Dichroite, 520'
Distillation, on salUng vegetables (of,
193
Docks^, William, patent for mak-
ing ivory black, 347
Downton pippin'/ account of, 464 '
Draining, 3^5
Drowned persons, on raising them,
29
Dubuc on sugar from appka a94
pears, 274
Duff, John, patent snuffers, 7t
Dumbell, John, patent for ginning
flax, 79
Dosodil^, 178
E.
£arth, new theory of. its motio|^
round its axis, 309
Eclipti^^ on its o^liiyaity, 32(u^
39 3»
INDEX.
^gewonh, Richird liOvell, en te-
legraphic commanrcatibns, 3 1 2
Electrical jars, on Wingfield's me-
thod of increasing their charging
capacities, 378
Electrical machines, on improving
them, 320.
Electric column of De Luc, 244
Electricity, on bursting iron cylinders
by it, 325
Ellis, Francis, on the propagation of
sound, 41 '
Englefield, Sir H. C. particulars of a
thundcr-dtorm, 483 j on the new
mountain barometer, 485
Equatorial regions, a physical view of
the American, 381
E^canda, a Spanish grain, 287
Ether, of the formation of iEu;etic, ia
grape cake, 462
Evans, T. S. on astronomical re-
fraction, 476
Euphorbium, 259
Eye, on its adjustment to distances,
140 ; a bath for it, 159
Eyres, G. R. on irrigation, 293
F.
Farrri in Hartfordshire, how manag-
ed, 361
Fccula, 213
File for papers, improved, 44
Ftles, on stone-ware, 149
Filtering* machine, Stephenson's pa-
- tent, 490
Finlatcr, Charles, on plucking ppta-
toe blossoms, 86
Fiorin, or butter grass, 368
Fire, Congreve*s' patent for secuiity
against, 353
Fire arms, Jones's patent skelps for,
73
Fishes, on the air-bladder of, 120
Flaugergues, Honore, on the dimi-
nution of dilatability of alkohol by
age, 244
Elax-seed, on its culture, 457
Flax spinning, Dumbell's patent,
Flint slate, 182 ' .
Floating bodies, 6z
Focque on making grape sugar, 254
Folscb, Fred. Barth. patent writing-
machines, 67
Forces, 155
Forcing-houses of the Romans, 467
Foictt-trees, on planting, 81
horsier, B.M. onDe LQcVel«etrkr
column, 214
Foster, T^lutmas, on meteorology,
132
Fothergill, Dr. on the fertilizing af-
fects of gypsum, 452
Frankincense, 259
Burze, on its properties, 235
Fusion, a new kind of, 171
a.
Calvanism, 103 •
Garaboge, 259
Ga$es, a hydrometer for the, 258 ; oa
their combination, 511
Gas lights, Matben's patent for, 415$
Winsor's patent apparatus im^
proved, 419
Gay-Lussac, on the oxidation of
metals, and their capacity of satu*
rating acjds, ilo
Gay-Uuisac a^vl Thenard, on t]i«
metals from the alkalies, 95, 180,
43^> 500; on amalgam of am«
monia, 433^ on potassium andso*
dium* 503 ; on muriatic acMl oxy-
muriatic acid, -510; on gaseous,
bodies, 5x1
Gieometry, on a new prineiple. intip-
duQcd into it by Legendre, 376
Ginger, on a new acid in, 216
Gladstone, J. on a n^w method of
yoking horses in threshing m^
chines, 457
Glass drops, S^kespearje iind Osier's
• patent, 417 '
Gough, John, on the prc^rties o^
solids in general, 150
Gra.pe-cake, on the formation of
acetic ether in, 4^2
. Grapes, on making syrup apd Sjuga^
from, 209, 254
Grasses, on the choice of theni for
meadows and pastures, 449
• Grass land, 09 laying down, 305,
107
Gre|f, Thomas, Qianagement oi a
farm, 361
Grindstones, Slator's patent for hang-
^roombridge, S. on atmospberiqal
^ refraction, as it affects astronomi*
cal observations, 476
Grove, John Thomas, patent foe.
building, 344 '
Gum ammo.n|iac, 259
Gun locks, Manton's patent^ 8a ^
11
INDtX«
03rfMuin» on its fertilising cfiectS)
H.
Hall) James, on the maple-tree, 293;
on the use of heath in feeding
stock, 294; patent stone-ware
shivers, 351
Hall, Rev. James, on a svtbstitute for
hemp, 299
Harness, improved, 395
Harris, Salem, on solar and lunar
influence in meteorology, 337
Harrows, anews^tof, 357
Hassenfratz on oxide of iron, 239
Hastings, Warren, on naked barlej,
289
Hawort, A. H. on the cultivation of
crocuses, 45$
Hauy, RepeJust, onairagonite, 17?;
on apophyllite, 181
Headrick, James, on laying down
pasture land, 305
Healy, Robert, a cupping instrument,
16 .
heath, on its use in feeding stock,
294
Hedges, 85
Hematites, 464
Hemp, on a substitute for it, 299
Henri, on a powder sold for ipecacu-
anha, 277; on horse chesnut, 211
Henry, Dr. William, on British and
foreign salt, 277
H^rschel, Dr. on the cause of colour-
ed concentric rings between object-
glasses, 468
Hides, Revere's patent for splitting,
410
fiooper, Stephen, patent thermome-
ter for ovens, 418
Hornblende, Labrador, 229
Horse-chesnut, an
Horses, on shoeing, 83 ; on barley
as food for them, 289 ; compared
with ozen> 295, 296 ; on brewing
them for draught, 357 ; on feeding
inrith potatoes, 368 ; on a new me-
thod of yoking in threshing^ma-
f bines, 457 ; on the language used
in managing) 458
Hot-bed frames, on their construc-
tion, 463
Houses, on constructing them with
earthen walls, 34 ; of equal tem-
ferature, 47
' t
Howard, Luke, on Dr. Bostock'l
meteorological nomenclature, 313-
Humboldt, Alexander, on the vol-
canoes of Jurillo, 117; a physical
view of the equatorial regions o€
America, 381
Husbandry, on broad-cast and drill^
301
Hutton, William, patent sickles, 69
Hydrogen, on some combinations of*
2l6
Hygrometer for the gases, 258
I, J.
Japanned wares, Valentine's patent
for ornamenting, 167
Indigo, experiments on, 107
Indigo- plant, chemical examina^oa
of it, 506
Inglis, Janies, on the curl in pota«
toes, 85.
John, Dr. analysis of some talcsr
Johns, William, apparatus for de-
composing the alkalies, 206
Jones, John, patent skelps for fire-
arms, 73
Ipecacuanha, on a powder soldforj,
277
Ir<)n, on its oxidisement, 239; stats
of the manufactory in Great Bri-
taia, 405 ; on marsh oiea of, 464
Irrigation, 293
Ivory black, Docksey's patent to.
manufacturing, 347
K.
Kedington, Rev. R* horses andoxta
compared, 295
Kitchen fire-place, Craige's patent,
348
Klaproth, analyses of several mine-
rals, 229 ; 00 Chinese rice paste,
463
Knight, Thomas, on a new principle
introduced by Legendre into geo-
metry, 376
Knight, T. A. on the construction of
hot-bed frames, 463 ; account of
the Downton pippin, 464 ; on tfie
management of the onion, 465 ;
on (the cultivation of the Alpine
strawberry, 465 ; on new VSilieUil
of the peach, 466
Kqblrabi, 298
V
U9XX*
Xa^Ql^f , BoutlUm, on oxalic acid ia
. fhttbsirb> i*)S 9 on CuraiuUu's par,
ptron srilUf 210
l^moge . a|i4 Vogel oo the action
of phosphorus and oxymuriatic
icid upon the alkalies, 97 -
lamp, Barton's patent, 70
lAod gained from the seat, 301
l^ngnag^ oscd to hor«c», 458
Laplace, on the ring of Saturn, 327 ;
on the olAiqaity of tkt ecliptic, 329
Lava, on the formation of lithoid,
171; on nodulet of it found in
difikftone, 249
Laogier, on a substance found in the
island of Caprea» 105 ; on scapo-
• Ittc, 1S3.
Ltoreos on tht ose of soda in the
Lawrence, William, on Und, gained
, loom the sea, 301
Itf y William^ on examining the di-
viMOn» of astronomical instru-
ments, 13
>I«iCBaiiv Charles, patent for check-
ing carriages, 165
lie Hardy, Charles, on parsoeps, 234
Leonon, Colonel, on an iron tunnel
to go under theThames^ 332
'luBtap 00 tiiat of Rospini* 17
lepeie^ Gratien^ on artificial puxzo-
lana, 185
£est«r* W. on washing xoots for
icattle, 3^9 . -
Linakcr, James^ on driving ships by
steam, 154
.ibofweody e^eriieenisrooi 8i
Xjrae, on its annufd pajolla;^ 476
• '
M.
Miahine iv splitting grauwi Wil-
li^msts paficnt» 412 .
Machinery, Watta's patent for oom-
biniog it for mills, 494
Hp|;jniiliiiii, ajoow discovery in, 142
Maiben, John, patent gas Ugbts, 4x5
Manley, Bdvard^ patent plough, #8
Maotoo, John, patent gun-lock^ 8q ;
pMQit time^-keepers, 162
Manures, on soapers' waste, 291 ;
on long dung^ 25^2, 367^ on Ume»
' W •.•
Maple-tree, 29^
Marl, on its natural historjFy 4^4.
Man^, W. on prime and ultimate
latios, 34t
Marshall andJ6<f^dof» patent ftat mA*
ing salt, 170
Mashing-roachine, Robinson's far
tent, 494
Maynaid, David, on spring cropst 36a
Mclanite, 229
Meuls, relation between their oxid-
ation and their capacity for samrat-
ing acids, 1 10 ;. on those from the
alkalies and earthb, 216
Meteorolites, 187,514
Meteorological table for 1809, T25
Meteorology, 132; on Dr. Bostock's
nomenclature, 313; on the solar
and lunar influences in, 337
Miller, John, on raising drowned ^
persons from under water, 29
Mills, Watts's patent for combining
machinery for them, 494
Mitford, Colonel, on Grecian barleji,
290
MoUerat, J. B. on the maauftctune
of charcoal in close vessels^ 100;
on acttic acid, 27X
Monge, Gaspard, on forces, 155
■ Moorcs W. OB iha penetcaiion of
balls, 487
Morveku, Guyton, a hy4ronitt4sr for
gases, 258
Mouchel on themaiiufactttrcof iron
and steel Wire, 142
Mounsey, Hev^ Mr* on fpnQgwheat»
Muriate of tin, 2^
Myrrfa, 259
N.
,Ka«al.tmp<o«oiiiat)tf, h$y
Navigation, aerial, 21
liewton» Thomas, maQhine.fbt chop-
ping roots, 26
Numberp, on tmisformiog them
from one scale of notation to.ano«
tber^ 51 *
KismeAcalproposttion, a carious one,
O.
Oaks, on planting, 300
' Oniop, on ifs management^ 41(5
Onion's, John, patent threshing^ ma-
chine, 419
Orr, George, o^ floating l)odiea» 62
Oxen, 6n s)>oeJng, 83 ; on their asp
in draught, 29^; on breaking
them for draught, 3^7 > oal^di^f
^em with m^lasses^ 3^4
I
INDEX.
f agct, C. W. S, on barley, 366
Paranthine, 186
Paris, mineialogical geo^^aphy of,
200
Parmentier on conseive of grapes>
209
Paroletti, Mod^sti, on the influence
of light oa the propagation of-
sound, 57
Parsnips, oa their ct^tare and use in
Jersey, 234
Bttley, Capt. C. W. on the French
telegraphs, 152
Peach, on new varieties of it, 466
Veanon, Dr. on houses of equal tem-
petaturc, 47
Pendulums, 317 '
^enwame, John, patent for plaster
casts, 343
Phosphorus, 426
Phosphorus bottles, on preparing, 206
Pichblende, 518
Plants, on packing tor exportation,
371
Plaster easts, Penwame's patent, 343
Platina, 194
PAoujhs, Mauley*s patent, 68; on
combining several together, 357 ;
on measuring their resistance, 357 ;
00 their mathematical construc-
tion, 357
Pocock, George, patent for geogra*
phical slates, 73
Potash, analysis of several salts of,
146
Pc»tBssram, 180, 183, 187, 503
Potatoies, on the curl in, 85; oa
plucking off their blossoms, 86 ;
on feeding horses with, 368 ; ma-
chine for washing, 369
Presses, De Heine's patent printing
and stamping, 161
Prieur on the double refraction of
sulphate of copper, 9^
printing upon stone, 138, .284
Prior, George, junior, un a clock es«
capement, 151
Puzzolana, artificial, 183
Pyrites, aAalysesof, 276
Rain in 1S09, 125
Rainbow, <^n a lunar, 40
Randolph, David Meada^ patent fo^
whed-caniages, 75
Saiios, 00 pniac and ultimate, 341
Reaping-machines, 45$
Refraction, atmospherical and asttiH-
. nomical, 476
Reid, John, on thoni hedges, 85
Revere, Joseph Warren, patent for
splitting hides, 410
Rhubarb, on oxalic acid in, 195
Rice paste of China,-463
Ricks, on covering, 84
Rings, coloured concentric, in ob-
' ject-glasses, 468
Ritter on alkaline metals, 183
Roads, plan for constructing, 87; oia
their preservation, 395
Robinson, Mr« patent mashing«Aa-
chiae, 494
Roller, a new one, 357
Romans, their foicing-faMses uad
fruits, 467
Rooks, on their benefit -or iojoiy to
the farmer, 450
Ross, John Duckett, an eye-bath, 150
Roxburgh, Dr. William, on the ' '
^inds of Coromandel, 373
^uta baga, 456
Rut):ieiford, Adam, on spring
and bailey, 363
S.
Saddtngton, John, on cabbages
turnips, 298
Saddington, Thomas, machine for
coverinf wire, »8
Sage, B. G. conjectures on g»!vani«ai«
103 i ob alatnine in meteoiolitc^.
187 •
Salisbttiy, WAKam, <in laying dowm
grass land, 397 ; on packing planes
for exportation, 371
Salmon, Robert, on constructing
houses with earthen ymlls, 3^
Salt, Matshail and Ni^or's patent
for making, I7p; on British and
foreign, 277
Sand, analysis of a black one, 1 14
Saturn, on its ring, '327
Scapolite, it6
Schmidt, John, pateot phaatanna*
goric chronometer, 164
Soott, Alexander, on threshing rasu
• chines, -84
Sea water, Archbold*s patent for
mailing frtsh water from it, 167
Seed grain, 296
Seeds, on the proper period for som*
ing, 304
\ -
I^DBX«
Shakespeare and Qskr*s patent glass
drops, 417
Sheep, 'on Merino, 8x, 285 ; 00
Wiltshire and Merino cross, 233;
on giddiness and )»tag(^ers in, 367 ;
on iattcning them with sugar, 445
Sheephouse, a cheap one, 305
Sheldrake, T. on the camera lucida>
60
Shells, on their use as manure, 455
Ship pumps, Shorter's patent for
nvorklng, 413
Ships, method of securing their
beams, 32; on driving them for-
wards by steam, 154
Shipwrecks, on preserving lives In,
^409
Shivers, Hall's patent stone-ware, 351
Shorter'sy Edward, patent ship
pumps, 413
Sickles, Mutton's patent, 69
Simpson, Rev. John, on the culture
of the burr-knot apple, 462
Sinclair, Sir John, on escanda, 287
Singer, C.J. on electrical machines,
320
Slate pencils, machine for making,
a7
Slater, John, patent for hanging
grindstones, 356
Slates, Pocock's patent geographical,
7» ; engraved ones for teaching
writing, &c. 408
■Snuffers, Duff's patent, 71
Soapers' waste, 291
Soda, on its use in the soap-works,
196
Sodium, 180, 183, 187,503
Solids, inquiry into their properties,
150
Sonnini on the Syrian asclepias, 102
Sound, on the propagation of, 41 ;
on the influence of light on the
• propagation of, 57*
Spencer, Knight, ant^iropo-telegraph,
42 ; on a camp telegraph, 403
Spinejle-pleonaste, 248
Spinning, Bradbury's patent for, 66
Spring crops, 362, 363
Spring wheat, 365
Staurotide, 229
Steam-engines, Witty's patent rotst-
tJvc, 349
Steinacher, Anthony Philip, on aco-
nitum napellus, 10 1
Stephenson, Mr. patent filtering*ma-
chine, 490
Stickney, W. on the choice of grassiet
for fheadows and pastures, 449 }
on the comparative benefit or in-
jury ^o the farmer, from rooks and
pigeons, 450
Stills, on their form, 2 to
Stone, White's patent for 'artificial^
160
Strawberry, Alpine, dn its manage-
ment, 465
Substance found at Caprea, 105
Sugar from apples and pears, 274
Sugar, on the fattening of sheep
with it, 445
Sulphate of alumine, 246
Sulphate of copper, on the double
refraction of it, 99
Sulphur, on its dccoihposition, 19T,
I98, 243, 250; experiments on i%
426
Sulphuretted alkohol, 213
Sun, on observing it, 387
T*
Talc, 232
Tarras, artificial, 18^
Tea, on its unwliolesomeness^ tt^
Telegraph, a camp one, 403 ; on
communications made by it, 312$
on the French, 152
Telford, Thomas, on a new canal,
,18
'fhackeray, Dr. W. M. on planting
forest-trees, 372
Thames, on an iron tunnel to go
under it, '332 '
Theatres, on their construction, 145
Thenard, on the coagulation of albu«
men, 241
Thermometers, on a new scale for
them, 207 ; on the diminution of
the dilatability of alkohol in them
by age, 244 : on Walker's proposed
scale for them, 316; on a metallic
one for high temperatures, 335 >.
Stephen's patent one for ovens,
418
Thomason, Phillis Bown, patent
umbrellas, 163
Thompson, Benjamii^, on Anglo*
Merino wool, 82
Thomson, Thomas, analysis of a
black sand, 114
Threshing machipe, 84, 304 {
Onion's patent, 419 ; new method
of yoking horses in, 457
Thunder-storms^ remarkable, 483 •
IKBS3&'
Hmekeepen, • M«stoii's pttenl> i€%
Tindei-lHitXy ppiettimtic, ^51
IbiffixMiliney on reddish JBiofiviaiiy
JkctB, Oft pkntiBg larcfa^ 37a; o»
planting foccBt> 3^2'
Tromsdoiff^ on sevcrai chemical sub*
stances^ 213 ;. on aloes, 257'
TioughtoUy Edwftr4> on dividing as-
tronomical instranients, I
Turnips,. on Swedish, 298, $€4,4$$
Tttroip-scedj on raising^ 456
V, U;
Vacca, Leopold, on magnetism^ 142
Valentine> Ghailes, patent for orna*
mental japanirares, 1(7^
f^tf^ Jonathan, patent axktrees, 41 1
Vauqaelin on chabassie, 187; on
datolHe, 244 ; on pidiblende, 518$
on benzoic acid, 5x9
Vanqnelin, and* Berthollet, on CuiFan*
dan's experiments upon sulphur,
298; observations on this report^
150
'Veneers, Brunei's patent machine for
cutting them^ 160
Vinegar, onmaking, 303'
Umbrella, Thomasen's patent, . 163
Volcanoes of Jorullo, 117
Urinary calculus, a new one, 414.
Urine of camels andiiorses, 287 j of
herbivorous animalsj 5 19 -
W
.J
Walker^ Ezekiel, on', pendulums^.
317; on the adjustment* of the>^
eye, 140
Walker, Richard, onanewscale for
the thermometer, : 207 ; on his '
new scale for thermometers; ^ x< ;
on a metallic thermometer for high ;
temperatuFcsj 335 ; on the: bariH
meter, 390, 394
Warburton, Peter, patent for deco^-
rating, china and glass, 169
Warning watch,Berrol]as*spatent^4i4
Warren, Thomas,- engraved slates for
teaching writing, &c. 408
Waters,- ii T« on oiea and molasscsr.
Wattsi W. patent^ t6r combinin|^
machinery for milk, 494
Weather, on its prediction by the
barometeri 390, 394
Wedgewood, J. on 'the cukure ofthe
dahlias^' 460
Wheat, on Sieilian» 286 ; on the
smut in, 369-
Wheel carriages, Randolph'^ patent,.
75; Williams's patent, 351; on-
constructing them, 357, 395 j,
Varty's patent axletrees for, 41c
White, John, patent artifiacial stone,
&c. 160
White, Richai dj an improved fil« for
papers, 44
Whitwortb,« comparison of) horses-
and oxen, 296
Wiebeking on constructing wooden '
bridges, 316
Williams, Charles, - on azHnuthal're-
fraction, 127; patent machine for
splitting beans, &c. 412
Williams*, George, method of secur--
ing the beams of ships, 3 z
Witltams', John, patent for wheel
carriages, 351
Wind, on the land ones at'Coroman-
^U. 373
Window-blinds, Barron's patent, 17s .
Wine, on applying conserve of grapes
to making, 207-
Winaor, Frederick Albert, patent gas
light apparatus, 419
Winter and Nisbet, a plan for con-
stmcting roads, 87
Wire, on the manufacture of iron
and steel, 142 ; machine- for co-
vering, 28
Witty, Richard, patent rotative steaant-
engine, 349
Woad, experiments on, 107^ che-
mical examination of 506
W»lIaston, Dr. William Hyde, on
cystic oxyde,-424
Wood, Professor, on the* motion of
the eanh round its axis, 309 <•
Wright, John, on weeding crops, 364
Writing machines, Folsch's patent, 67;
Zeolite, OB^ the cubio^ of Term, 187;
£|ID OF THE SIXTH VOLUME.
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