Experiments and Observations, Tending to Illustrate the Nature and Properties of Electricity: By William Watson, Apothecary, F. R. S

Experiments and Observations, Tending to Illustrate the Nature and Properties of Electricity:By William Watson, Apothecary, F. R. S.Author(s): William WatsonSource: Philosophical Transactions (1683-1775), Vol. 43 (1744 - 1745), pp. 481-501Published by: The Royal SocietyStable URL: http://www.jstor.org/stable/104498 .

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[481 3 I. Encterimenzs ard Obf vations, -ending

to ill?J?rate the Aatare and Propertiew of Eledricity: By William VVatfon, 4pothecary, F. R. S.

if Letter o Martin Folkes, &i7; Pr. R. S.

S I R, 2tad S fieswaZ M#ReJ*gs __> H E S*o c I E T Y has

Jf the Royal Society, betnvten t

March 28, and Odober 24, 1, * lNgheardXfrOnlrOmC 1745 bere printgd with At/- | of their Correfponw t¢ttivw. - t dents in * Germang, that what they call a Vegetable Quintecnce had been fired by Electricity, I talre tllis Opportunity to acqllaint youy that, on Friday E^reninD lafi, I. fucceeded, after having becn difiappointcd in many Attempts, in fettint, Spirits of \Vine oll fire by that Power.

The preceding Part of the Week had been reZ markably warm, and the Air very dry; than which nothing is more neceSary towards the SucceSs of eleEcrical Trials: To thefe I may add, that the Wind was then Ea(lerly, and inclining to freeze. I that Evening ufed a glaSs Spllere, as srell as a Tube; but 1 always find myfelf capable of fending forth much more Fire from the Tubc tllan from the Sphere, probably, from not being fufficiently uSed to tlae laPr.

Qq q I had _

_ . ,- ^ _ .

* See an Account of Prof. Winckler's Book of EteAricity in thie 7>anl. N°. 47,. p. 166. Prof. Mollman, Tranl W°. 47S pv 239. Dr. Miles, ib. p. 290. ZFntklerE E xperlmcnts} tb. p. 307* Mr. de Bozes,Troa7J T9.M,7J.p. 419. C*M.



E 482 ] I had before obServ'd, that, altllos * Non-eleEtric

Eodies, nzade elecrical, lofe almoll all that Eledri- city, by coming -eitller nvithin or near the ContaA of Non-eleEYrics not made cleAxical. It happens other wif: with regard to EleArirs perre, -when excited by rub'ving, patting, eic*; bccaufe from the rubbed Tube I can fomctitnes procure five or lix FlaChes from diSelcnt Parts;!as though the Tubc of two Feet long) itlRead of being one continued Cylinder, con- fiLicd of five or fix {eparate Segments of Cylinders, each of which gave out its Eied;tricity at a diffel:ent Explofion.

The Knowlet,e of thls Theorem is of the utmoPt Corsfcquencc towards the Succefs of eledcri-cal 13x- perim.nts; inafruch as you muA endeavour, by all pc>Sblc means) to collcEt the Whole of this Fire at tlac fiSl3e time. Profsffior Hollfnan feenls to- have endcan?our'd at this, and fucceededX by having a tln Tube; ill one End of which he put a great many TllreadsX whofe-ExtrenzitAes touch'd the Sphere whcn i-n Motion, and CACil Thread colleded a tuantity of cleEtrical FireX the Whole of which center'd in the- tin Tube, and WCtlt 0 at the other Extremity. Arsother thing to be obServed isv to endeavour to make the flafhcs follow cach other fO faR, as that a

fecond.

* I ca'*l EleSrics per fie, or originally ElecGrics, thoCc Bodies. in wbicb an sttratve Power towards llght Subftances is eafilly exeited by Fridtlon; fich as GaSs, AInocr, Susphsirs Seating-wax, and moR dry Parts of Arlims s7 ac

Si*k, Ha r, and eh lik*. I- call gon-elec¢ric5} or Conduditors of Elc&ricity, th.o,ze lXc«dirs, fn eJni<-h 1:> ab re Pfoperty ts now at-a'l, or very nightly perq ccptlbe; fuch aS WOOJS A!;im!s livinaor deZd. M¢t ZJlS, an vegetab'e Sub Rances. SPe Gr<, nx Fay, De0X3X!iers Wheler, in ttee PhtlofopAicaZ. Tr;Jopcizons, N2. 4I 7* 42 2 423. 43 Is 4$36 439. 444 4S3 4S4 46ot 462#. *64.



t 483 g fi¢condsmay be vifible before the firR is ext;nguifh'd, When you tranfmitthe eledrical Fire alonr a Sword, or other- Infirument, svhoSe Point is {harp, it ofrell appears as a Number of dilEemirlated Spa-rks, like wet Gunpowder or Wild-fire: But if the Infirualellt has no Point, you generally pctceive a pure bri;>tlt Flame, lile what is vulgarly call'd the Bl?zeball, xvhich gives the Appearance of Stars to fircd Rockets.

The following is the Method I made uSe of, anct svas happy enough eo fuccced in. I fufpended a Poker in filk Lines ; at the Handlc of wllich I hunO

fenZeral little Bundles of white Thread, the Extre- mities of which were about a Foot at right Angles from lhe Poker. Among thefe Thrcads, which werc all attraded by the rubbed Tube, I excited ttRC greateA eleftrical Fire I was capable, whilLt an A{IlRant, near the End of the Poker, held in his Hand a Spoon, in wvhich were the warm Spirits. Thus the Thread communicated the EleEtricity to the Poker, and the

Spirit was fired at the other End. It muflc be obfzrv'd in tilis Experimcnt, that the Spoon with the Spirit muR llot touch the Poker; if it does, thc Eled:tricity,

without any Flafhing, is communicated to the Spoons and to the AiElPrant in whore Halzd it is held, and fo is lofle in the Floor.

By theSe means I fired feveral times not only the cthereal ISiquor cor ThlogiJ?on of Frobenigs, and red:tified Spirit of Btine, but even comrnon proof Spirit. Thefe Experimcnts, as I before obSers ed, were made la& Frtiay Nigllt, thc Air being perfeEtly dry. S&nday proved wee, and Moraday fomewhat warm ; rO that the Air was full of Vapour, Wind South-weft, and

Q q q 2 cloudy.



vr 484 ] gtoudy. Under thefie Difadvantages, on Mordvy Night Ilattempted again n;3y Experiments; they fuc cecded} but writh infinitely more Labour than the precedin, becauft of the UnfitneSs of the Evening for fuch Trials. Yollr Candour will not permit you to think my MinuteneSs trivial, with ret,ard tO the CircumRances of the WeatherX who know how many Things mull concur tO make- thefe Experiments fucceed. I Ihall wait wlth Impatience for a proper OppOttUnity tO hae theSe Experiments repeated in yout Prefence; and am, with the utmoS ReEpeEt}

SI R, AMdtrJ>a-Strect, March 27.

5. Soar maJ? obediew IIgmble Nergodnt,

l?Y. Watfon

II.

A Legter to tEe R O Y A L SO C I E T YL

GentlernenX R¢a Apri1 2S* Lately acquainted you,. that r had beeg 74s 1 ab]e to fire Spirit of Winey SPhlog:dox of FrobeaigsJ and comrnon proof SpiritX by the Power of Eledricity Since wilich (till YeRerday) we havc had but one very dry fine Day; viz. MonX days MIpril I s. Wind E-. N. E ; when, about Four o' Clock in ttle Afternoon, I got my Spparatus rcady, and fired the Spirit of Winc four timcs from the Pcaker as bcfore? three times from tlle Finger of a Per-fon eleflcritScd} Ptanding upon a Cake of Waxs

and



[ 485 ] snd once from thc Finger of a fecond Pctfon fand int, upon Wax, conzmunicating wieh the firA by means of a Walkin:-cane held between their Arms cxtended. The holizontal Diltance in this Cabe be- twecn the glaSs T(lbe and the Spint was at leaa ten

P¢ect. You all know, tllat there is the repulfive Power

of Eleciriclty, as weli as the attraerive; inaEmuch as you are able, when a Feather, or huchlike li^,ht SubX fiance, is replete with EleEtricity, to d-rive it about a Room., wluich Way you pleafe. This repulfv¢ Power continues, until either the Tube loSes its ex cited Force, or the Fcather attrad;ts the MoiRure from the Air, o-r comes near to fonze non-eleEtric Sub-- flcance; if fio, the Feather is attraded by, and its E}ecX tricity 1oF in whatever Non--eleEtric it comes neare In eledrified Bodies, you fee a perpetual Endcavout to get rid of their ElccSricity. This induced me to- make the followig Experiment.

I placed a Man upon a Czake of Wax, who loeld in one of his Hands a Spoon with the warm Spiritss and in the othcr a Poker with the Thread. I rubbcd the Tube amengll tile Thrcad, and eleEtrified him as befole. I then ordercd a Perfon not eleEritied to brill , his Finger near lhe ]!tiddlc of tht Spoon; upon whtch, the FlaE from tile Spoon axld Spirit was violent enough to fire the SpiXit. iS E%perimCnt I then repeated three times.

In this Me:thod, the Perfon by whofe Finger the Spitit of \Aline is fired, feels the Stroke much more violent, than svhen the eled;trical Fire goes from hinn to the Spoon. This Way, for the lake of DiAin&cionw xse will cail the repulfve Power of Eledvricity.

The



S 486 ]

The late Dr. iDe/"gBliers 11as obfierved, in llis ex ccllent ViX<rtation concerning ElcEtricity, ' That

there is a fore of Capricioufilfs attcnding therc Experiments, or fometlling unaccollntalolc in tilcir

C Phnomena, not tO l)C lC(iLlCed tO any Rulc. For

< fometinzes arl Experimctlt, xvhicIz 11as bcen made

' [everal times fuccelllstclt, x^ill all at OL1CC fail*'

Nosr I inzaoine, that the grcareR Part if not the

NVIzeIe of this WIattcrX depends upon the MoiRure or DryneSs of tlle Air; a fudden thouoh fli3hr A1- tcration in whicll, pexhaps xlot furfficient tC) be obvious to our Faculties, may bc perccivcd by the stry fub- tle Fire of ElcEtricity. For,

llt, I conceive) that thc Air itSelf (dS 'las been

obferved by Dr. lDeJ4aguliers) is an ElecWric perle, and- of the vitreous Klnd; therQfore it repels the

EleEtricity ari(ing from the glaEs Tubc, and difpotes

it to eleflcrify svhatcver non-eled;trical Bodies rcweive

the Effaqvia from the Tube. 2dly, That Water is a N7onveledric, and, of con

fequence, a Conduflor of Eldricity. This is exem- plified by a Jctt of Water being attradted by the Tllbe, from eithcr Eledticspzrfie condudiil:, Eleflricity, alzd Non-eledrics more Icadily wllcn wetted; but what is more to my prefient Purpofe, is, that if you only blonv througll a dry glats Tllbc, tlle Moillure trom

your Breath svill caulc vllat Tllbe to be a ConduEtor

of EleEtricity.

Thefe bein^, premifed, in proportion as the Air is

replete with xvatery Vapours, tloe Elcdricity arifin^,

frotn the TubeX inRead of bcin^, condudecS, as pro-

pobed, is, by means of thcfe Vapours, communicated

3 to



r4s7 ] to thc circumamblent Atmofphere, and diMpatcd as fall as excited.

rhis Theory has ocen confirmed to me by disrets

Experiments, bt}t by rlone morc remarkably than on

the Evening of the Day I made thofc bcfore-men

tionvd; nvhen the Vapours, whtch in the Afternoon,

by tlle Sun s Heat, and a brisk Gale, were dilIlpatedX

and the Air perfedly dry, deScended again in great

Plenty, upon the AbSence of bothX and in the Even

ing xaras very damp. For between feven and eight

o' Clock, I attempted at,ain the fame Experiments in

the famc manner, without being able to make any of them fucceed; though all thofe mentioned in this Paper, wsth others of leLs NXote, nvere made in leSs than half an Hour's time.

I am the tnore particular in this, being willing to fas?c the Labour of thofc, who are defrous o£ mak;ng this ICind of Trials. For, alrhough Some of the leS r Experiments may fucceed almoR at any

time, yct I never could fitld) that the more remarke able ones svould fuczesd but in dry Weather. I ams

Gentlernen,

Zour moJ? obedient, Zondon, SpsiZ 2Ss

74S * Hxmble Sersant;

W. WatfonX

ll}t A



[ 488 3

IIt.

ALetZer to the ROYAL SOCI E T YH

Gentlemex, R¢fX O&Ob 24 tN fome Papers I lately did myfelf the 'f 45 s Honour to lay before you, I acquainted aou of fome Experiments in EleEtricity; particularly I took notice of having been able tO fire Spirit of Wine by what I called the repul{ive Powrer thereof; svhich I have not herd had been thought of by any ofthofe German Gentlcmen, to svhom the World ls obliged for many IZurprifinD DiL>overics in tllis Part of Natural PhiloCophwt.

How far, {tridrly rpeaking, the Spirit, in this Ope- ration, may be faid to -be fired by tlle replllrlste

Power of EleEtricity, or how far that Power, which repels liDht Subflcances svhen tully impregnated with Eledricity, fires the Spirit, may probab!y be the SubjeEt of a future Inquir jr; but, as I am unwillino tO introduce m0re Ttrms into any Demonllration than what are abfiolutely neceIary for the mole ready Conccption thereof, and as inflanzmable Sub fances may be fired by EleEtricity tWO different \ATays, let the fo] lowinO Defiattions at preLent fuflice of cach czf theSe Methods.

But firl} giste me Leave to premif Xthat no inflam mable SubRances will take Fire, when brought into or near the Contact of Eltctrics per J4e excited tO

Electricity. This ESec£ mull bc produced by norx- e] ectrical Subllances impregn ated Wit 11 E 1 ectricity re

teived from thz cxcitin;, Elcstrics lver ;e. But to teturn:

J



489 zfl, I fuppofe that inflammable Subfiances are fired

by the attraftive Power of EledricityX xvhen this Ef- feft arifcs from their being brought near excired NonZ eledrics.

2d+, lDhat irwflammable Subllances are fired by the repulfive Power of Eled;tricity; when it happcns, that the inflammable Subftances, being; firel eled;trified themfelves, are fired by being brought near Non- eledrics not excited.

This Matter will be better illuflrated by an Exam- ple. SuppoSe that either a Man Itanding upon a Cake of Wax, or a Sword fufpended in Sllk Lines, are eleEtrified, and the Spirir, being brought near them, is fired, this is faid to be performed by the attradtive Power of E'eEtricity. 13ut if the Man elec- trifiedX as before, holds a Spoon in his Hand contain- ing the Spirit, or the fame Spoon and Spirit are placed upon the Sword, and a PerSon not eledcrified applies his Finger near the Spoon, and the Spirit is fired from the Flame ariftng from the Spoon and Spirit upon fuch Application, this I call being fired by the repulfive Power. Of the tWO mention'd Kinds I generally find the repulfiNe Power {rongeR.

Sixlce my lallc lLommunication, the Spirit has been fired both by the attraftive and repulftve Power thro' four Perfons llanding upon eleflrical Cakes, each communicating with the other, either by the Means of a NValking-carue, a Sword, or any other non- eleAric SubRance. It has likewire been fired from the Handle of a Sword held in the Hand of a third lwerlon.

I have not only fired Frobenigs's SPhloziJ?on, rec tified Spirit, and common proof Spirit, Sut alio SaZ

R r r solatiZe



[ 49o ] tiatzle oleofiW} Spitit of Lavender, dulcified Spirit of Nitre, Peonyowater, Dgy's Elxxir} HelwetiBs's StyptiCa and fome other Mixtures where the Spirit has been very confiderably diluted } lilrewiX dsltilled regetable Oils) filch as that of Turpentine LemonX Orange-peelsZ and tuniper > and even thofe of them which are fpecificaTly heavier than WaterX as Oil of SaCafras; albo refinous SubPrances} fuch as Baltam Ci- pivi} and Turpentine; ail vthich Send forthy when warmed an inflammable Vapour. Buc expreid vegetable OiEs, as thoM of Olives} LinfeedX atld AW1* naonds) as well as Tallou7) all whoSe Vapours are un- inflammabIea I havc not been able yet tO fire, but thefe lndeed will not fire on the Application of lighted Paper. Befidesa if thefe laR would fire svith Xighted Paper, unleS their Vapours were inRamma- ble} I can fcarce conceive they srou'd fire by Elec tricitg; becaure in firing Spiritss eir. I always peF ceive that the Electricity iaps, beibre ir comcs in Contact with their Surficesa and therefbre only fires their inflammable Vapours.

As an excited N7on clectric emits aRmoPt all its Fire} if once touchSd by a Non-c]ectric not excitedX I sras d¢Srous of btint fatisfyd} whether or no the Fire emitted wouid not be greater or leli in proportion to the Volume of tlae clectrified lSedy. In order to thi<, I procured an irota 13ar about S Fcet lon> and near I 70 Pounds in Weirht > tlliR I electrfied ying on Cakes of M7ax and Relna baut oblirnted the Fla{hes arlfing thercfrom not more vioient than tho fiom a common Poker. In ulaking this Expcl-imwI£> being svisfinO to try the repuliive Force, it once hap- pend; that whilS the Bar was at one End electrifyinga

a SPOQ[\



[ 49I ]

a Spoon lay upon the other; and, upon an Affi1Ptant's pouring fome warm Spirit into thc Spoon) the electrical Flafh from the Spoon Enapped, and fircd the firS Drop of the Spirit; which uruexpectedly fired not only the whole Jett as it was pouring, but kindled likewife the whole Quantity in the Pot, in which I nfually ha^7e it warm'd.

I find, in firing inflammable Subllances from the Finger of a Man danding upon Wax, that, teris parib&s, the SucceEs is more conRant, if the Man, inflcead of holding the Thread (the USe of which I communicated in a former Paper) in his Hand, the Thread is fuEpended at the End of an iron Rod held in one Hand} arld he touches the Spirit with one of the Fingers of the other.

If a Man, fianding upon the electrical Cake with a Di& or deep Plate of Water in one Hand, and the iron Rod with tlle Thread in the other, is made electrical, and a PcrSon not electrified touches any Part either of the Plate or Water, the Plafhes of Pire come OUt plentifully; and svhere-ever you bring your Finger very near,, the NVater rifes up in a little ConeX from the Point of which the Fire is produceda and your Finger, though not in actual Contact, is made wet. The fame Experimerlt fucceeds through three or more People.

In firing inflammable SubPlances, the Perfon who holds the Spoon in his Hand to receive elle electrical Flathes, when tlle Pinger of the electrified Perfon is brought near thereto, not only feels a Tingling in his Hand, but even a {light Pain up tO his Elbo-w. This is moPr perceptible in dry Weather, when the Electricity is rery powerful.

R r r z There



[ 492 J

There is conGderable Difficulty in firing EleArics perJ4e, fuch as Turpentine arld Balfam Capivi} by th: repulfiere Power of: Eledricity 3 becauSe, in this Cafe,, thefe SubRances will not permit the Eleftricity tO

paEs through thcm: Therefore, when you would have this Expcriment fiucccedX tlle Finger of tlle PerSon who is to fire them, is to be applied as near to the Edge as poIElbIe of thefe Subflances when warmed in a Spoon, tllat the FlaChes from the Spooll (for theSe SubQances will emit none) may fnap, wllere they are fpread tlle thitlneIl7 and then fire their Ef- JiBvia. This Experiment, as well as feveral others, 6¢rVeS tO confute tnat Opinion, which has prevailed witll many, that the Eledricity floats only upon the

W * * . bllrtaces ot oc les. If an eleftrical-Cake is dipp'd in Water7 it is

thereby made a Condilctor of Electricity; the Water hangin:, about it tranEmitting tlle electrical E>via in fuch a manner, that a Perfon Ra1zdirzD thercon can by no means be electrified enough tO attract the Leaf Gold at th-e fmaJleL} DiPrance ) thougil ehe Per- fon flfanding upon the fame Cake whcn dry attracred a Piece of fine Tllread llanging at the DiRance o-f tro Feet from his Pin£;er. We muLl 11erc obServe) that tlue Cake being of an ainctuous SubRance, tiae

\Vater svill no*N^rhere lie uniformlyt tllercon but ad- here in feparate- Molergl; fo tllatX in tllls In{iance, the Electricity jumps from one Particle of \57ater tO

a)aother) till the Whole is diiAlpated. From the Appearance of tlae Threads, amongA

svhich I rub the Tube, I can frequelztly judOe) tllou^,h tlle Spitit lnay be nzany Fect diRant from them, xhetller or tlo it wrill firc; becaufcX when the Per-

fons



[493 ] bns ttanding upon tlle NVax are nzade electrical enou¢t to fire tlue Spirit, the Threads rcpcl eacl other at their losver Parts xyhere tlley are nor con find, to a confiderable Dillance J and this D &ance is in Proporciorl as the Threads are made eXcctrical.

If two Perins ltand upon electrical Calles at abotlt

a Yard's Difiance from cach otherX one of which Perfons, for the fake of Dil:linction, we will call S} the other B; if X, when electrified, touclzcs B Kq

lofes almoA all his Electricity at- that Touch only, which is received by B, and Ropped by tlle electrical Cake: If ¢ is immediately electrificd again tO the farne Det,ree as lDefore7 and tonches B} tlue Snapping is lefs upotl the Touch; and this Snapping,- UpOtl electrify ill g X, grows leSs and l els} till B, bein^, inz- prcgnated with Electricity, -though received at Inter- vals, the Snapping will no longer be fienXible.

That GlaEs will repel and not conduct the Elec tricity of GlaEs) lzas been mention'd by others, who -have treated of this Subject; but the Experimerlts to determine this Matter muA be conductcd with a great deal of Caution; fbr, unle& the glaSserubey inrended to conduct the Eiectricity, be as warin as the external Air) it will feem to prove the corztrary}

unlefs in very dry Places and Seabons. Thus I fometimes have brought a cold though dry glaSs TuLre ncar threc Feet long into a Roonu where there has been a Nunlber of People; svhcn, upon placing the tube UpOll filk LinesX and layint Some Lcaf-Silvcr upon a Card at one End, and rubbing anothcr glaSs Tube at the otller, the Silver has, conerary ro Ex- pectationX beell thronNn off as readily as from an iroll Rod At fitA I was furpritcd at tllis Api3car

ance;



E 494 ] ance; but then con jectur'c that it muPl artfe from the Coldnefs of the GlaLsX conden&ng the floating Vapour of r1wc Rocxm. In order then to obviate this, I warm'd tlle Tu?oe fufficiently, and this E5ect was no longer produ^'d, but the Silver lay per_ fectly fiill.

Ii a Sumber of Pieces of firlely Epun Gla!:R, cut l:o about an Inch in LenE3tll, little Bits of fir<< Wire of the fame Lcngth, of what Metal yQU picaSe, and fmall Cork-BaglsS are eithcr put atl togcllcr, or eacll by ttlem<;lvcx) into a dry pesater Plat<> or uporl a Piece of polithed MetalX vlley make, inXthe follow- ingManner, a very oddanelfurprifingAppearance. Let a Man, (tanding upon electrical Cakes, hold this Plate in his Hand, nvith the Bits of GlaLs, WircX br. detachcd fro al evach others as mucll as convcniently nzay be; wben he is electrified, let laim caufie a Per- fon nanding upon the Ground to bring another piate, his Hand, or any otller STon-electric, exactly os?er the PlateX containin^, tllefe Bodies. When his Hand, br. is about cight Inches ovcr them, let him bring it do-N^n gently: As it comes near, in proportion tO the Strcngth of the Electricity, he will obZ fervc the Bits of GlaEs firS raife themSelves upright; and tlwcn, if he brings his Hand nearer, dart dlrectSy upX and llick tO it WitllOUt fnapping. Tlle Bits of M7ire xvil fly up likcwifeX and as they come near thz Hand rflap aleLld; you feel a fmart Stroke, and fee tize fire ariSnr fiwom them to the FIand at every Stroke: Each of thefe, as foon as they have diI: cllarged their Fire7 falls down again upon the Plate. The {:ork-Balls alfo fly up, and firikc your Hand, t fall again directly. You have a conSant Suc- C£ffi10S of ehefe Appearances, as long as you conti-

6 nue



C 495 ] nue to eleEtrify the Man in whofe Hand the Plaee: is held; but if you touch sny} Part either of thz Man or Plate, the Pieces of GlaEsa which before were uporu their Ends, immediately fail down.

Some few Years ago, Sir yames Lowther * brought fome Bladders fill'd with inflammable Air, colleEted from his Coalmitles, to the Royal Soriety. Thls Air flamedX upon a lighted Candle being brought near it. This Inflan:lmability has occafion'd many terrible Accidents. AIr. Magd, a svorthy Member of this Societb, made at that time, by Art, and thew'd the Soriety, Air wxatDtly of the fanle (8uality. I was delirous of knowinr if this Air svould bc kindled by cledrical Flahes. I-accordingly made fuch Air, by putting an Ounce of Filings of Iron, an Ounce of Oil of Vitriol, and four C)unces of Water, into a lElarense F]ask; upon 5rhich an Ebullition enfued, and the Air, nvhicll arofc from theSe Materials, not only fill'd three Bladders, but alfoX upon the Appl- cation of tlle Fin¢er of an eleerified PerfonX took Flanzc) and burnt near the Top and out of the Neck of the Flask a confiderablc Timcw Wllcn tile FIame is almoft out} {hake the Fiask, and the Elarr,e revives. You mu0, w.ith your Finger dipped itz VVa.ter} moiEen the Mouth of thv Flvsk as fatt as it is dried by the Heat within) or the Eltftricatv svill not fire it; Be- cauR the Flaskn bcing an Eiectric peDr J; will not fnap at tlae Application of tile Finger) svitllout the G!ais 9ocing firIt made non-wXlectric bvy wcttXn¢. It has fometitnes happenvd) it tlle fin¢cr has bewll .>p_ plieel before the inflammabie Air has fbund a rcady Exgt from the Mouth of thc Elasl<) that thc FIaCh has

JSIicd

t See thtSe Travf S°. +42. p. 282.



[ 496 ] filled the FlaslrX snd gone of with an Explofion equal to the Firing of a large PiPcol; and fometimes indeed it has burR the Flask. The fame Effz3ct is produced from Spirit of Sea Salt) as from Oil of Vitriol ; but as thz Acid of Sca-Salt is much lighter than that of Vitriol, there is no NeceIMIty to add tho Water in this Experi- ment.

Thofe who are not much acquainted with Che- mical PhiloSophys may think it very extraordinary, that, fronl a Mixture of cold SubRances, wllich, botll con junctly and fcparately, are uninflammable, this very inflammable Vapour {hould bc produced. In order to Golve this, it may not be improper to premifeX that iron is cotnpounded of a fulphureous as nvell as a metallic Part. This Sulphur is fO fixed, rllatX after lleating the Iron red hot, and even melting it etter

fo often, the Sulphur nvill not be dilengaged there- from: But, upon the Mixture of the Yitriolic ftcid, and by the Heat and Ebllllition xvllich are almoR in- Rantly produced, the mctallic Part is diffolved,, and the Sulplluro which before was intimately connected theresvith, being dtSengaged, beconzes rolatile. This Heat and ESullitioxl continue, till the vitriolic Acid is perfectly faturated with the metallic Part of tile Irc)n; and the Vapour, once fired, continues to flameJ until, this Saturation being perfected, no more of the Sulphur flies of.

I has?e heretofore mentiolled, how conSlderably pcrfcctly dry lNir conduces to ehe Succefs of theSe Experiments; but we have been lately informed, by a1z Extract of a Letter, that Abbe 70Aet xvas of Opi- nion, that thcy would fucceed in wct\Veather, pro- vided tlae Tubes were made of GlaEs tinged blue with Zaffer. I 11ave procalrcd Tubes of tllis fort, but,

after



[ 497] after giving tllem many candid Trials, I cannot tllinlc tllem equal tO their Recom-mendation. I firA tried one of them in a fmart Shower of Rain after a dry lE)ay, when the Drops were large, and the Spirit fired tl}ree times in about four Minutes: The fame Effcct facceeded, under tlle fame Circumllances} from the white one; but, afrer three or four Hours raining9

wllen the Air was perfectly wer, I never sould nzake it fucceed. And, to illu{irate this Matter further, I have been able, when the Weather has been very dry, xvith once rllbbing my Hand down this blue Tube, and applying it tO the End of an iron Rod fix Feet longX tO tbrow off reveral Picces of Leaf-Silver lying upon a-Card av the otller End oftllis Rod; whereas I never have been able tO throw it off by any mearus in vcry svet Weather. Befides, I am of Opinion, that, after tlle clcctrical Fire is gotle from the Tube, the Tubc 11as no Share in the conducting of it: My Sentimcnts on that Head I laid before you in a former Paper: For if tlle filk lines are wetted, they diffure all tlle Electricity; and tl e fame Effects hap- pen, when the Air is wet, be your GlaSs of nvhat Colour it will.

It may not be improper here to obferve, that Zaf- fer, which is uSed by tlle GlaSs-makers and Ena- naellers, is made of Cobalt or Mundick calcined after tIze fubliming the Flowers. This being reduccd to a very fine Powder, anct mixt wvith tsvice or thricc its own Weight offincly powder'd Fliruts, is moiflcned wxtith NVater, and put up in Barrels, ill which it foon runs into an hard MaSsX antl is calld ZaSer.

A dl4y Sponge hanging by a Packthread at the Fad of an electvified Sword, or ttonl th: Hand of an

S ff clcctlifie



[498 g

clcArified Man) rivcs no Sibns of lcing nzadc clcctrical If it is well Soaksd in WaterX xv1zrc^csScr it is toucllydX yon both fcc and fcel tl<c ciedritval Spark<> lNlot only to) but) if it is {4o full of Wattr tllat it ftlts frorn the Spon)cX tllok DlJops in a ('ark Rooiiz} rc cci + d tlpon your l1aladt 11ot osuly {1a{1w at1ti ftlap} but yQU perccive a prlcking Pain. If yon hold your twland) or any non-elcdrical Sul>aances, vcry ncar} tI-e War tera whicll had ceaScd dropping; nvhcn tTle 3ponc xvas noe eleEl-rifiedt drops again upoll ius bcing electrified; arld tlle Drops fill in Proportioll tO tlle re cciv'd Eledricity as though the Sponge srere gently kueezd bctwecn your Fingers. I was defirous to knowv if I was ablc to clc&rifbr a Vrop of cold NVa- ter) dropping from the Sponre) enougll to fire the Spirit; but after many uruiuccefsful Trials} I was fbrced to defin; beaauSe the cold Water droppin7 from the Sponge nor only coold- tlle Spirit too azuchX but alb render'd it too weak: Likewsfe cv¢ry Drop carried with iv great Part of thc lite2Sicity from thC

SpongeJ I tllen conEderd in wllat manner I could rive a

Tcnacity to rlle Water rufficient tO make thc Drops hanO a coslftderable Time; and this t broturllt abour bsr making a Mucilage of the Sec^4s of Flcaworrv A wet Sponge then, I4ueez>d hard) and fild Y8titll tlli5 cold Muclage7 was lcld in the Hand of an cledrio fied ManX wluen thz Dl*opsn f6rced out by the Elec- tricityX aIE1lled by thz Tenacity of the LiquorX huna fome Inches from the Sponge; and) by a Drop of tlltls) I fired not only the Spirtt of WincX but lilse- \MiQrC th4 inflammable Atr beXre-mcntioncd) botla xvitll arld wiihout the Explofsn. Wlwat arl extra-

ord snary



w -

. 499_ ordi1zary EffeA is this, That a Drop of cold Water (for the Secds contribute nothin^,> but add ConFLl- ence to the Water) {hould be the M>diz of fire and Flamc ?

Camphorisa vegetableRcfln} and, of collRquenceX an Eled;ric ter . Tllis StlbRancc, notwithllanding lts grcat I!flaln;<alDil Cy, sxtill nct eake Fire frotn rllc F2Scr of a ManX OL any orllcr Body eleAriSed/ thc xnade very ssartn, atad tlle Vapours attSe tizetcfronz i

grcat Abundarlcc; bccauk, lleithcr Eloctsics pES P cxcitcdo or elcctriS d Bodics) excrt tllcir Forcc iy

filapping upon FJ1+ cctrics per J2> thotugh not cxcited

I* you break Canlp'<or Eluall) and waLxn it in a Spoon

it iS not mclted by ticat like otiler Rclins > but, iv ttRAt Heat srere continucd} it would ali prove vola- tite. To Canlphor tnus wtarmd, tlle iin3cr of az cIcccrificd M<n) a Sxrord} or fuch-like, wEilI in fnapping, CXCIt itS rOrCt UpOlZ tile Spoon} and the circumarnSicnt Vapollr of the Camplwor will be fired

thercbyta and lirilt tip tile NSllole tuantity expofed.

Tlne falme ExpPrinzent facceeds by t'lc repulftste Ponvcr

. .

O , t cctrlclty.

A PokcrX thorougluly iDnitcd put into Spirit Qf NVine, or into the dillillcd Oil of Vegetables pro-

dures no Flanac in citllcr. It indced occations the

Vapours to ariSe from the Oit in reat ^@bundance;

but if you electrify this heatcd Poker tllc electrical

lilalles pr>bently kindle Flamc in cither. The Expe-

rim*erst iS the [ame sv7ith Canzpllor. Thek Experi-

tnents} as well as thc follosvinz, fufficiently esTincc,

that thc electrical Firc is truly Flaule., and that ex-

frcmely fubtil.

srfz I have



[ 500 ] I have madc feveral Trials in order to firc GunX

powder alonct nv}aic'< I tried both warm and colct nallole arld powderXd, but nevcr could fuccekd: Anct twis ariac<, in parea from its Vapours not bcing in- Rarnmablo, and in part froln its not bting capabTe c>f bein, firnd by Flame i unleEs tllc Sulplaur ill tllc CotnpoStion is nearly in tlle State of Accenfon. This nve fee, by putting GunpoxYder into a Spoon svith rectified Spirit, whicll, wilen lightcd, svill not fire the Poxzrder, till, by the Heat of thc SpOOll from the burnint, Spirit, tlle Sulphur is allmollr melted Likexvifee if you hold Gunpowder ground very fine in a Spoon over a ligllted Candlc, or any otller Flame, as rOon as the Spoon is llot enough tO

melt thc Sulphur, you fee a bluc F1ame, anct inltantly the Powder flaShes off. The fame EffzMcts are obEerved in the rPaIvis #ltninars, compos d of Nitre, Sulphur, and- fixcd aIkaline Salt. Befides} xvhen tllc GUllpON^der iS s7ery dry, and grorlnd vcry fincX it (as you pleafe to make tllc Experiment) is citller attractedX or repell'd; rO that, ill tlle fir(t CafeX the End of yoalr Finger, xvhcn electrificd, nlaLI bc coser'd over suith the Poxvder, though laeld at fotnc DiRancc; and in the other, if you electrify tllC

PowdcrX it will fly off at the -Approacli of any llon- clcctriSed Subfiance, and fiometirnes csten WitilOUt itx

But I can, at Pleafllre, fire GunpowderX and evcll dif- charge a MusketX by the Power of Electricity, when the Gunpowvder has been ground with a littlC Cam- phor, or with a fcsY Drops of fonze inflanznaable chemical Oil. lDbis Oil fomesvhat moillens tlnC

PonvderX and preYentS itS flying away: The Gune ponvder tllcn lzcing svarm'd in a Spoon, the elec ricat

Fl21hcs



[ 5°I] FJafEesfiretheinflammableVaporlrvluichfirestlleGun- powdcr: But the Tirnc lDctsreen tllc Vapour fil illg tlle Posvdcr is 1e {hortX thae frequelatly they appe{.r as vlle fameJ anct not fucceSivc Opcrations, nvhercin thc Csur- pON&uCZ itStlf fcems fired by the Eicdricity: Al d, ill- (lccd} tEl: firR tiSlC this Experinzel5t fiucceeded) tile FiaSh was tio XtlWcn and uncxpcdcd, that tlae Hand of aly Anillalit, svho touchfid til: Spoon svith his Finger} xras conlsldcrably fcorclld. So that theke fceals a fburth Ingredient neccCary to make GunX powder rcadily take Fire by Flame ; and That fuch -a one as will hei:,llten tlle 11zflammability of tlle Sul- phur.

In common CaRsX the lighted ASatch7 or the little Portion of red-hot Glafis which falis among thc Pos^> dera and is the ttefult ofthe Collifioll from tlle Flint and Steel, fires the Charcoal and SulphurX and thele the Nitre Eut if to tllclSc thrcc Ingrcdicnts qou add a fourth, vzx. a regetabJe cllcmival Oil, and gently xYarm tllis Mixture, the VilX by tlle Warmtlz, mixes intimately wirll the Sulphur, lowcrs itS Confillence, and makes it readily take Firc ly Flame.

In tilefc Operations notsvithAanding I alsvays tnade uSe of tlle fincR-fcer.ted Oils of OranDe pcel) Lemonss anel fuch-like, yet, upon tlle leaft warmilzD tllc Atix- turcX tic rank Smell of Ealfitn (i. e. of thc ready Solutlon of Sulphur) svas s?cry obvious.

1I. X



Documents

Experiments and Observations, Tending to Illustrate the Nature and Properties of Electricity: By William Watson, Apothecary, F. R. S