Experiments on the Congelation of Quicksilver in England. By Mr. Richard Walker; In a Letter to Henry Cavendish, Esq. F. R. S

Experiments on the Congelation of Quicksilver in England. By Mr. Richard Walker; In aLetter to Henry Cavendish, Esq. F. R. S.Author(s): Richard WalkerSource: Philosophical Transactions of the Royal Society of London, Vol. 79 (1789), pp. 199-211Published by: The Royal SocietyStable URL: http://www.jstor.org/stable/106694 .

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Xgig ]

XIX. .Esperimens on tffie Congelation of tazckver in Eliglatlds By Mr. Richard Walker, -zx a Lever o Henry Cavelldinls EJ. F. R. S.

FRead May 28, 1 789*

bS I Rt

I NOW leAg leave to troubte you with the particulars of my experimetlts relative to the congelatiotl of mercury; to

which I all add an account of a few cxperiments, relatitag to the produdion of artificial cold, made filce my lafi Paper ssas written.

Exp. I On December 28th laIX, a fasrourable opportulzity oSered of beginning fome experimeruts on -the congelation of mercuryX which 1 was defirous of eieEtillg completely; how far I have fucceeded will appear i21 the fequel

For this purpofe I prepared a mixture of diluted vitriolic acid (redtlced by water till its fpecific gravity was to that of water as I,SS96 tO 1) alld ltrong fuming nitrous acid, of each equal parts. I preferred this mixture of acid lDecauSe it has l)een found by Mr. WIC NAB, in Hudfotl's Bay, to be capable of producing much greater cGld, when the temperature of the materials at mixing is rery lover, than the llitrous acid alone; the

former fillklllg a fpirit thermometer to 54°, tlle latter llearer

lower than -- 46°. Tlze glaSs tllbe of a mercurial thermonleterv with its bulS

half filled with mercalry7 svas pro>ided, this o-ccurrillg to me H h 3 85



20O Mr. WALKERSS X^perimenZs on the as a cotivenietit method of aScertaitwiilg when the merellry was coligealed; for if, after being fubjed?ced to the cold of a frigo- riC.c mixttlre, the thermometer glaSs Ihould be taken out and inverted, atid the Inercury found tot remain completely fuf- petlded itl that half of the bulb now uppermo{l, no doubt can remain of the fuccefs of tile experiment; all hydrometer, with its lower l)ulb half an itich in diameter, and threefourths full of mercury, was likewrife provided, in cafe any accident ffiould happetl to the other.

It may l)e proper to premife here, that in all experiments of this kind I remove each vellqel, when the: liquor it contains is fuiciently cooled, out of the -mixture in which it is immerfed for that purpofe7 immediately previous to adding the fnow ar falts with ititentiol] tQ gesnerate a 1li11 further increafe of cold; and likewife prefer adelillg the fnow or powdered falts to the

liquor? inRead of pouring the liquor UpOIl thefe: it is Ilece{ary

alSo to Rir alzout the fllow or falts7 whilft cooling in a frigorific mixture, from time to time, otherwife it will freeze into a hard maSs, and fruIlrate the experiment.

A half-pint glaEs tumbler, containing two ounces and a half of the above-mentioned diluted mixture of acids, being immerfed in mixtures of nitrous acid and ftlow, uIatil the liquor it colltained was cooled to--3O°, was xemoved out of the- mixture and placed UpOIl a table; Enow, likewife previouny cooled in a frigorific mixture to-X 5°, was added by degrees to the liquor in the tumbler, and the mixture kept Ilirring until a mercurial thermometer funk to-60°, where it remained Ra- tionary; the hydrorneter was then itnmerfed in the mixture (the tllertuometer glafs havillg been broken in the courfe of the experimetlt) and Rirred about ill it for a {hort time alad 0X1 takiIlg tile hydrometer outX and gently {haking it, I

I perceived



Congelation of !tuicXzJ"lver in- Erlglatld. zo }

perceived the mercury had already acquired the catlfiRetace of an amalgam, and after immerfitag it again for a few tninutes, alld therz taking out a2ad itlverting itv I was gratified for -the firk -time with the I;ght of mercury irl a Rate of perfedc congelation. I applied tny hand to the inverted glafs bulb, this footu loofened the folid tnercuryX which, oll Ihaking the hydro meterX was diRind?c]y heard to knock ss7it1l force agaiLlflc the glaSs; it was then itnmerfed a fecon(l time, and wvheIl t.kenL out was foundi adhering to the glaSs as before. I IlOW iIlVefted

the glafs again, and kept it in that iituatioIl ulltil the whole of the mercury melted, alld dropped down globule after globule into the ftem of the hydrometer. The interval of titlle fror takirlg the mercury out of the fiigorilEc misture in a folid ItateX the latl time, to its perfed liquefadion, was not tloticed; buts UpOll recolledcion immediately afterwardsn was fuppofed to be not lefs thatl three or four mir}utes In a fucceedillg experiment this citcutn{lance w0ras atteIlded toS and the frozen mer cury, weighing fevels fcruples, was not elltirely rxelted under feven minutes, the temperature of the air + 3o°.

The experiment which :follows I conflcler the moR extraw ordinary, becauSe it proves beyot;ld a doubt, that mercury may be frozew IlOt OIlly here itl fummer, but even in the hotteR- climate, at a.lly feafon of the year,; by-a combination of fii- gorific mixtures, in the way defcribed iil the PhiloSc>phical TranfadtionsS Vol. LXXVII. ; p 285 i}w which attempt tcX

freeze mercury, made April 20 I7879 the temperatule of the air alld materials being + 45°, I certaillly reached (without the aElRallce of fnow ol ice) the point of mercurial congelation, but had then no fati$fadory proof that ally part of tlle mercury was abSolutely congealed.

Exp



Xez Mr WALKER9S jEXpertfoZeSt! on tSc

Exp. %. 011 Decemler 30. three oullces of a mixturecom poSed of filOllg fumillg nitrous acid two parts, and firong vitriolic acid atld water each -one part, were cooled in a half ;pint tumbler itnmerSed in a frigorific mixture, till the temperature of the diluted mixture of acirds was reduced to-3o>* The turnl)ler was then removed out of tbe mixture} and Xvitriolated natroll (GLALJBERSS falt) its very fine powder, pre- viouXly cooled to -- I4° by a frigorific mixtureX added by degrees to tlle liquor ial the tumbler, Rirring it together until the merF clury irl the therluometer furlk-to-54°. The hydrometer uSed ill the former experiment, with its lower bulb tllree- fourths f lll of mercury, was tlOW itnnerfed and fiirred about in the misture for a few minutes, ̂Then on taking it outs and itlvertiIlg i-t, I had ttlc fatisfadcion to find the fame proof of the mercury beitag fiozen as in the former inIlance. .Tt was imtnediately {hewn to the gentlemen prefent, who expreXed likevife their entire fatisfadriots. NeallyXfour ounces c)f the powdered falt was added; but, I beliesres fome was added after the greatell eied was produced. I had no nitrated ammonia by me, otherwife I ffiould have ufied UpOIl this occaflolzS inRead of sritriolated natron alone, a mixture of theSe two falts in powder, in the proportion of feven parts of the former to cight of tlle latter. rI he temperatllre of the room in which thefe experiments were made Ftas +302; each time, and the mercury taken from a jar contailling fesreral poullds.

Ex\p 3. By atl experimellt made purpofely on January TOE laR, (12 which Dr. ]3otrRNE was prefent, I have found that mercury vllay be congealed tolerably hard, by addillg freXh falletl filossrX at the teanperature o-f + 32o to firollg fumitlg nitrous acid, pteviounv cooled to between-2,>° aLld 3Q

sYhlcll lllay be very eafily atld quickly effeded by immerflng 6 the



(X8ongelation of tutcZtyÊserxn EtlgIand. ac>^3: t1Xt veINel cotlsaillill; tlle acitA ilu a misture of filosv and tlitrous. acid

I uSe the fizraing taitrous acicl UpOtl al1 occafiotas, lzecauSe tllt does IlOt reqUild to be diluted, cold beil> immetliately pro d:uced on ttle iinalleR additiottl of f)osnr.

Exp. 4. 0tl Julluary I 2, St Dr. TI{OMSON'VS requeXr, I; repeated the experitu@nt of freezi}zg metcury, at tl1e Atzxtotny Sch:ool itl CllriR Church in tlze preStI>£e of rlhe hoIlourable- Mr WENMANX the rev Dr HOA-RE, r. SIBTHORPB j. lIliOJ S.

Dr. THOMPSONS the; rev. Mr. JACKSON 0E Chrsil Churcllg arld- Mr. Wooo of thls placey a gelltkman well KIo>Z11 fort

. . . * . . z1s lzgeIlulty 1n mec zanlcs. For tho;s- purpofe ssrere provided a fpirit thermemeter gra

sIuated very low, atlcl a snercurial thermometer graxduated to; - 76o7 tsro thermotneter glafl>es, with bulbs very llear9 if llot quite," an irsch in diameter each,^ otle filled wtth mercurW 11early to4 the orifice of the tubej which was l@0t openS the- <3ther w-th its bulb half filled^ alld at1 llydrometer- svith its lower bulzb (conflderably lefs thatl either of the others) lilie- wife half filled wtith inercury ;. the temi?eratUre of tbwe room RE.

this tirne + 28°* A panv coataining tline oullces of the mixture of acids pre-

pared as; ill the firI} experiment, was placedR in a larger pan9 containitlg nitrous acid, and thistr ia a frigorific mixture of nitrous acid an fllows colltained in aI1other pan much largere When the rlitrous acid in the fecolld pali was cooled by this-^ mixture to-18°, and the mixed acids in the imalleR pal1

early as much 1lOW at fomewhat betweetl + 20° and + 25°,.

the temperature cf the opell air at that timeS was- added to the nitrous acid ill; the fecond panX until-the fpirit- thermometer fualk to near 43°-^ then the thermometer, with its bulb; half filled>? was immer.Sed a fuIEcoexlt tinae, and whell; taken

XUtg.



204 lWr. NVALKERSS Experit>ezrs on the out, tlle mercury ila it was found collgealed, alzd adlzering to the giafs. The 1)lll contaillillg the tnixed acids, atld shtch lad lJeetl removed whilk tile Illow 0vas added to make the lecolld tnixture, xsas J1OW replaced in it -irl order to be cooled; atld vllell tlle mixture of acids was reduced to the temperature of-;>4°, ftlosr -previouIly cooled to-18° was added, keepitlg the mixture Ilirred utltil the mercurial thermomerer fuuk to-60°; its temperature by the fpirit thermotneter was then found to lDe-5 1°. W The three glaIfes containillg the mercury to be frozen were;

I10W imI11erIed iN this mixtureX alld having beell moved about itl it for a collElderable time, during which the fpirit tllermo meter rofe fcarcely one deg;ree, were theil feverally takets out an(l examined.

As-the examination of the frozen mercury was more immediately ullder the;infpedion of Dr. THOMSON, I {hall tranfcribe here that gentleman's account of the phnomena.

" When the freezing mixture was fuppofed to h-ave produced its eSedc, the bulb which washcompletely filled was takell out, atld l)roken on d flat Rone: by a moderate Itroke or tvwo with atl iron hammer. This bulb was eleven or twelve lilles in-diameter.

'rhe folid mercury svas feparated iiltO feveral- iharp alld brilX liant fragments, fome of wIflch;bore handling for a- Ihort time before;they returtled to a fltidv form. -- One-maSs>- larger than the reR, confiRitlg of nearly one-third of the whole bail, afforded tlle beautiful appearance of flat plates-converging towards a cellter. Eacls fof theSe plates was about a litle in

I)readth at the external furface of the ball, becoming nar- rower as it Shot itlwards. Thefe facts lay in very different plalles, as is common in the frafture of any. cry{tallized ball;

whether



Congalaton of taic}WrSver ZX Etzg'la21d. 2by

otShetiler of a brittle me-ta:l or of the earthsX as itl balIs of caI- tareous !ItalaAite. The folid 13rittle mercury lI1 th;e prefe2lt inRance bore a very exadc refsmblance, both il;l ;colour and plated firuEture, tQ fulphurated allt.irnondr, and efpecially to the rad-iated fpecimeIls frorn Auverglle, -betfore they are at altl tarlwifhed.

IlRead of a folid center to this balls it feeffled ts if there had been a central cavity, of a;boutltwo ;lifles in dlameter, a confiderable portion of which was ev-idellt itl the fragmellt juR deforibed, at that part to which the radii convergedW It is indeed poffilble, that this may have been merely the --receptacle of fome part of the mercury remainillg fluid at tEze cell;ter The hollow within was {hinillg, IJut its edges were meitller foft nor moulderilog; on -the contra.ry they were Iharp ancl well defined : nor was the brilliancy of the radii attributable to any esudation of mercllry as from all amalgam.

111 the two fmaller bullzs, which were oly half filled, tlze mercury preferved its ufual luRre otl the furface in contadc witb. the glafs, as s7vell as on that furface which it llad acquired itz. becoming folid. The latter was occupied by a conical depreI; fion, the gradatotas of which were marked by collcetltric

.. . nes. One of thefe hemifpheres was fEruck with a hammer, as in

the forme-r inItances but was rather flattened and.crulhed tlzatl broken. The other, otl being divided vith a Iharp ch.iAels ihowed a metallic fplendv3ur orl its cut furface, but not equal- lint, the polifh of a globule of fluid mercury."

Thirteen ounces of fnow irl the whole verEe found to. lla-ve beenad-ded.tothemixedacids; but fome was added tolower its temperature after the glaXes coIltaining tlle mercury were Ataken out, an.d the fpiritsthermometer had riferl afew dgrees.

Yo. LXXIX, I i This



ob Mr. trALKE:RsS Experionenzs on the lnhis sXras a dsly renzarkably favourable for fuch an experi

rnezz. My tlaermometer expofed to the open air Rood, at three quarters paR eigIat this tnorllillgs at + 6O, which is a very extrslorditzary degree of cold here; but this experinetst ssras ot begun till 1looll. Exp . S On Jatz . X 4. I fi oze mercury at the Anatomy

School again7 in tile preSeIlce of the rev. the DeaIl of ChriIt- Church, the rev. Drv ̂IIORNSBEr atld DrO THOMSON.

Four outaces llossr of the mixture of acids, prepared as in the filI} experiment, were cooled ilu a tumbler to so°> which required fonesvilat naore than all equal weigllt c)f fnows cooled Ilearly to the fame temperature, to produce the greateft effe&. This was fomewhat lefs than ill the laI} experirnent, the fpirit thermometer fiIlkitlg 1lo lower thail-46°, owing chiefly to the wenther having becotne much warmer, the temperature of the opetl air lDeillg I1OW +36°. The mercurial thermometer im- merCed ill this mixture futlk to-55°, where i!t became lia- tionaly; therl two thermometer glafies olle half 15lled with mercury, and the otIaer filled to a cotlfiderable height up the the tube, after being immerfed fome time, were examined. Upoll breakillg the Ihell of glafs from the former of theSeX the- mercu.y was found itl a perfeEtly folid Itate; but its upper furfacen which was highly polithed, atld of the colour of liquid mercury, itlllead c)f being oIlly tlightly depreISeElg as had been Seen in every other itlItance which affiolded all oppor tUIaity for i<fpedtior}, now formed a perfeAly inverted hollow coIle. Ttiis great deprefElonS as well as tEle concelltric ciscles melltioned in a fortner ilfiaIlceX I fuppoSe, might be oNVillg to

a rotatory motion accidentally given to it whilfi congealingv The folid mercury was beatell out, but having been fuffiered to lie fome time oxl tlle tal.)le for illfpeEtion, very quickly

6 melted



Congelation of tuickJ"lever t't :EnglAnd. 2O

melted into liquid globules. The flexibility of folid mercurv was clearly to be obServed in this lzeautiful fpecimetl; for tlze external furface, particularly the upper tlain rim of the- COtl-

cave part, was evideIltly belut by the firIt getltle Srolie of the hammer. The glolze of mercury in the other glaEs, eevhicll was very fmall, exhibited Ilearly the fame phxnometla, as iIl

the iIlRances lzefore mentioned. It happened ill thefe experimexlts of tnine, colltrary to what

hasgenerallyoccurredtootllers, thatthe mercurynever flIzk lower thall--60°, feldom fo low, itl the thermometer, atld I)ut little l)elow the point of mercurial cotlgelation itl the tubes of the thermometer glaXes filled llearly up to the orifice, with a view to fhew the colltradioll of mercury in becomillg folid ly its great defcent in the tube. On refleAing on this circtlmRance afterwards, it occurred to me, that the further defcent of the mercury in theSe experiments was prevetlted llot folely by the mercuryfreezing in tlle tube, the caufe cotn- mollly affilgned, but rather by the quick formation of a fpheri- cal thell of folid mercury within tIze bulb, by the ludde generation of cold.

Dr. BEDDOES exprefiitlg a defire to exhibit folid merculy at his LeEture before llis ClaSs, I undertook to freeze fome at tlle Laboratory orl March lxth laIt, arld now refolved to fatisfy myfelf refpedring tile caule which prevetlted the lovver (lefcetlt of the mercury ill my former experirnents. 111 tllis, as well as

ehe former, the mercury ill a thermometer graduated to-60°> and likesvife iaw a thermometer glrafs, filled nearly to tlle orificey which lengthened lts {cale to Ilear-330°s futlk ollly Xl ft\r degrees below the point of mercurial congelatiotl, and tllell remained liationary. After waiti2lg fome time, I took ttle thermometer out of the mixtllre, and obServed ttle bulb appa rently full, axld ehe {hort thread of mercury above ullbrokelle

I i z I tlO'



to8 lklr. WA.LKER'S Experimcnts 0,8 tEe Ia lloxv emlraced the lower pXirt of the tul)e with my hand a

têsv fiecotldss rtiiiIag it UpOl! ttle upper part. of ttle bulb; aI<d UpOll takillg it asst<ay, 1 foulld ttlat the svhole of the mercury hac3 fubfided itltO tlie buIb, whicll it dad llot noxv: quite fill,; a {n<all tzace at the top of the bulb ren1-aiiling emp.ty. I thell. took out tile tilerinonieter glafs alid applied my halid to tlie tube, lJut tthe mercury remained Itatiotlary ut-ltil I fulik my halid fo as to comazutlicate heat to that part of the Ijulb w.hich is. im.me(liately cotlIleded *vith the tube, whell the thread of mercury dropped entirely illtO.t the- bulb. It was nosY immerfed again for a ffiort time,. then talierl out, and the.{hell of: glaSs beatgn oS; whicll expofed a globe of folld mercury, llearly al1 iSC1i ;I1 diameter. Thts b.ore feveral very finart drokes lvithA a hammer bef9re it begall to Iioquify, but wasv not perfeEtlyX mallealble.

ll the courSe of thefe exp;erimetlts, felreral fragments of the fo}id mercurys were thrown into mercury in its ordinary liq.uid Itate,t and were foutld.to flilk witSi confiderableK celerity.

In continuing -my refearches refpeEtilzg the-means of epro ducing artificial cold, I harre found that ptlofphorated natroa- produces rather more cold; lty folution. irl; thee dilutedi nitrous acid than the vitriolated natronX

At the temperature Of; + 50C, four parts of the diluted nitrous acid (prepared by mixing firong nitrous acid with half its weigElt o£ svater) required.. eight parts ofJ that noutral!falt.inr ine powder. to be adde.d, in order to gauSe the therm0meter to. fixlk to - 6°; and again,. byw the additiota of five parts of n.X- trated- ammoruia itl fine powder, the thermometer. i:unk . fo^.low a;-. I 6oj in. the whole ̂ fixtyfixvdegrees

A mixture of this kind.made the thermometer fink- from 8Qo

Qho temperature of the materials before msxing) to o°.



Cougelatisn of ,uic]J>lter in Ei)glar.tl. nme

I was direEted to the trial of this falt, by the like remarkalule felll;-ltion of coldneIs without pul}gel]cy, tvhich, rith its ther fimilar propeTties tQ iceS firl:} iIlduced me, svhil{E pur- iBuing the ISlbjeE of cold, to trv tLse eSeA of diRolvitag the uitriolated natrexl itz tlle nlitleral acids.

I>.qual. qusltltities, by sv<tigllt, of phef}nhoratecl Il arrorl an cl vitl iolated natrotl, vere ev"aporated .<e7Xlrate]y o er a g;elltle fi re. vlIltil each was redvlced to a perfe£tly dry posvdetb I theIl zveighed them, andt fouad the refidullln of the phofplworate(t. natroll fotnewhat lighter thatl that of the vitrioR;ated Ilatroxa;

froln whence it is proltable tE)e former cotatains the greateS quantity of water of cryRallizatiotl.

I flave foulud, that each of tlle neutraI falts wllich ptodttce any remarlsable degree af cold by foltu}on ill the nzitler.ll a:idsy t.iz. phof orated tlatron, vitriolated lla$rol1, alld vitriolated. magne.iiafi lofe this property elltirely, when deprived by ally means of their water of cryRallization.

A ihort tilnr after I flad firR fucceeded il} free;zing wtater iil fumtner, by one mixture compoSed of three different falts i;u; water (h>villg l)eell itlduced to try the effeEt of fu£h a met.ElodS from the cotfideratiotl that water, alreadjr faturated<ith otles kind of falt, will diIlolve a portion of anwother, an(l after that a third, or even more), I met with the account of atl experiment made by M,. HOMBERG, related in one of the earlier. Volumes of the Philofophical Tranfad:tions, in wlwich it is faid hc produced an extraorditlary; degree o£ cold, by pouring a pinti alld a half of dillilled vinegar upoll two pounds of a powder compofed of equal parts of crude fal ammoniac and corrofive fublitnate, and fhaking them well together. I immediately (July 30, 1786) prepared a mixture of this kind in ftnaller quantitys but found it ;eroduced oIlly thirtytwo degxees of.

cold



tia Mt¢ WALKER'S Exp@ritavwts oa Xhe

£oldt tlae temp¢rature of tbe air aud materials l)efore mixillg lJeinp; 639; s^rhich is no tnore than I have found tnay be effeAed l)y a folution in water of crude fal ammotliac alone, preu vioufly dried alld powdered.

13y a trial made with great accuracy, I filld, that even the mixtule conzpoSed of diluted vitriolic acid and vitriolated 1la- trotl is adequate to ally uSefill purpoSe that may lve required in t1ze hotteR courltry ; for, - by adding eleven parts of the falt in fille powder to eight parts of the witrlolic acid diluted with a1< equal weight of water, the thermometer ftl1ak from 80°, the rnean tetnperature of the hotteR climate, and to which theSe materials were purpofely heated before mixillg, to rather lclonv 20.

Vitriolated tlatron, added to tlae maritze acid undilutedX proZ dvlces very llearly as great a degree of cold as when tnixed with tlle diluted nitrous acid. At the ternperature of 50°, two parts of the acid, require three parts of the falt ill fitle powder, svhich will fltlk t1ze thertnometer to o°; and if three parts of a mixed posvder, colltailling equal parts of tnuriated am xnonia and tlitrated kali, be added afterwardsX the cold of the nixture will be increafed a few degrees more.

The frigorif1c mixture above defcribedv compoSed of phof- rlsorated nGtrotl a1ad nitrated ammotlia diIlolved ill the diluted itrous acid, beitlg the moR poxverful9 it will probably lze

foulld tmok consrenient for freezilg mercury, whell II1OW iS

llot to be procurecl. Tlle materials for this purpofe nzay be previorlny cooled ila mixtures made of maritle acid with vitri- olatecl natronX muria£ed amTnonia atad nitrated kali, in the plôpOlotiOnS melltioned above, this beitlg much cheaper tlaan thofe alade svith (liluted tlitrous acid and very nearly equal it eSedE

Ill



CogelaZion of !tgtskJsltser in SEtlglalld. 2 I t It1 my 1a{t Paper I melltioned a freczing £XlisrSture, made lDy

diflolving a powder compofed of equal parts of murislted ammonia and nitrated kali ill water alld thereill dileEted fix parts af the mixed powder to be added to eight parts of water; blzt

. . .

I have found fnce, that the bell proportioIJs are, five parts of tlle former to eight of the latter, by wtllich I have futlk the thermometer from sc)° to I 1 °.

HaVing 110W profecuted my fubJeA relative to mistures for gellerating artificial cold witilout the uSe of ice, from a poElble method propofed by Dr. WATSON (}i:Says, Vol III. p. I3v.), for freezillg water in fummer itl this climateX atld carried it on to a certain method of freezing, not only water, but evell mercury, in the hotteIt climate, I now intend to take my leave of it.

I have the honour to be, &c.

RICHARD WALKER



Documents

Experiments on the Congelation of Quicksilver in England. By Mr. Richard Walker; In a Letter to Henry Cavendish, Esq. F. R. S