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E L E e T R
The f?8, thT:(oTr, muO be, that the clt.'!ric m.mrT
js cootioually daning from the douJs in one place, allhe
f.lme time thal il is dJdwged fTomthe emh io ,oolher.
And it js a necendry conie~ueoce frolO the w~lole, thal
the doudsfeTve as cOOOUcrOTS !O conre)' the e1dlric Anid
fTom dlOfe places of Ihe emh which are overloadeu wilJ¡
jI, lOthofe which aTe exhaulled of il.
That gml quantilies of eleélTic maneTdo fometimes
ruth out of pa,lieu!arpan¡ of the earlh, and rife Ihrough
the air inlo lhe higher Tegions of Ihe almofphere, he
tr.inks is cvident from the grtal quantilies of fand, aOlls,
and other light fubllaoces, whieh have oflen becn wTi<o
up ioto the ,ir. and fcmered uniformlyom a large Iraél
of country. No OtheT knowo ellieient cauCe of thls phe
nomeoon can be a/ligned, except the wind ; aou it has
been olCerved when there was no winJ lIirriog; a"d the
light bodies hal'e eveo beeo cmied againll the wiod. He
fuppoCes, theTefoTe, lhat theCe light bodies aTe raiCed by
a Iarge quantity of eleélric matter, i!fuing OUt of the
eanh, whcre it was overcharged with it, aod anraéling
aod carrying \Vith it every Cubll.nee that coulo Cerve as a
cooduélor in its pa!fage. AII theCebodies, beiog poll',!fed
of ao equal quaotity of thecleélricfluid, \ViII bediCperCed
equallyin the air, and conf~queotly orer that p3JI of the
eanh \Vhere the fluid \Vas wantiog, aod whither they
ferve !O coovey it. liad theCe bodies been raifed by the
wiod, they would have beeo diCperCed at random, and in
heaFs.
This comparatively rare phenomeoon, he thinks, ex·
hibits both a perfeél im1ge, aod demonOration, of the
manner in which the vapour! of the atmoCphere are rai·
fed tO form Ihunder·clouds. The fame eleélrie mmer,
wherever it i!fues, a!traéls tO il, and c.mies up into the
higher regions of th~ air, the watery panides that are
diCperfed in the atmofphere. The tle(tric matter afcends
to the higher retions of the atmofphere, being folieited
by the Ids refillance it finds there Ihan in the common
mafs of the eanh; which, at IhoCe times, is genwlly
ver, dry, and cnnfequentll' highly cle/lric. The uni·
formil Y\Vith which lhunoer·douos fpread thcm(dves,
and fwcll into arches, mun be owing 10 their being af·
feaed byfOlDe cauCe which, like the eleélric matter, dif·
fufes ilCelf uniformly w~ere·cver il aéls, and tOthe re·
finance they meet with in afcending throl/gh the airo As
a proof of this, ileam, rifing from an eleélrified eolipile,
dill'ufcs itfelf wilh Ihe fame uniformill', and in fimilar
arches, extending itfelf towards any conduaing Cubo
Ilance.
Thefame cacfe which firfl raifed a doud, from 1'3.
pours diCperfed in lhe atmoCphere. dra"'s it lOtho:e Iha!
arealmdy formeo, and continl/es to form nc\V ones ;
till the ",hole colle(teo mafs extends Co far, as to reaeh
a pan of the eaTlh where Ihere is a deficiency of the e·
leélric fluid. Thither too. will Ihole douds, replete
wllh elcélricity, be IIrongly . tméled. and there ",ill the
el~étric matter diCeharge i&lf upon theearth A chan·
nel of eOOlmunic31ion bcing, in Ihis manner, found, a
frdh fupply of tlcf¡ric m:lllcr will be raifed from the o·
verlonded pw, and will c/)l1linue tObe convc)'ed by Ihe
medium of the dOl/ds. till ,he cquilibriuOl of Ihe fluid,
betwccnthe twOplace; (lf Ihe ealth be rc'lored. When
T Y.
Ih~ dou,l, m atIraaed io lh~ir plf::·~~ h)' t~oCe parts of
the emh where there is a J~Ílcitncy of Ihe fluiJ, dlofe
d~taehed fr~g nents are formed, and alCo IhoCe uniforOl
dtpending proluberances, w~ieh , in fo,lIe edfes, are th~
cauCe of water.fpvUl , and hu rri.;ane~ .
TllH Ih~ clcalic Illllt.:r, II'hidl forms and animates
Ihe thunJer·clouJs, ¡f1';cs flom plam fu bdow th~ Cur.
face of Ihe ea"h; alld Ihat it buries ilCdf Ihere, is pro.
b'lble frolll th~ d.:ep hol;¡ that haoe, in many plJCCs,
wen ma.!e by lighlning. Flaflles of li2hlningh.' e. alfo,
beco feen to atiCe f,om fubterraneous c:trilies, and from
",e1"- Violent inund.tions hove accompanied Ihunder·
Ilorms, nOI occ••fioned by rain, bltt by waler burlling
fr6m the bowels of Ihe emh, fro~l which ir muJl have
been diflodged by fome interoal concuflion. D:ep IVells
h..'e been known lOfill f.lner in thunder·Jlorms, and o·
thers have conOantly grown tltrbid at the approach of
Ihunder.
This verl' rife, as wel! as the whole progreCs of thun·
der·clouds, has fometimes been in a manner vifiblc.
Exhalations have been frequentlyCeen to rife frompdTIi.
cular careros, attended with a rUOlGling noife, and 10 af·
cend into the highcr regiolls of the air, with al! the phe·
oomena of IhulIJer·nOrms defcribed above, according tO
the deCcription of perfons who li ,ed long before Ihecon·
neélioo bmveen eleélricity and lightning WdS fufpeéled.
The grea¡e[¡ di/liculty attenoing this Iheory of the o·
rigin of thundcr·florms relates to the colle,qion and in·
fulation of eleélric mmer within Ihe body of the ealth.
With "fpeél tOthe furmer, he has nothing particular 10
f.y. Some opmtions in nature are cenainll' attended
wi:h a lors of Ihe equilibriuminthe cI~élric fluid, bUI no
perfon has yet a/ligned a more probable caufe of the re·
dundanc)' of elcélrie matter whieh, io fa8, oflen abounds
in Ihe cloud$, Ihan what we mal' fuppoCe po/lible to take
place in Ihe bowelsof the earth. And fnppofing th~ 10Cs
of the e~uilibrium po/lible, the Came c3ufe th,t proouced
the elfcél\Vonld prevent the relloring of it; fo Ihat not
being ble to force a way, at leall one fu/liciently rcady,
throu&h the body of the eanh, it would i!fue at Ihe
0100 convenienl rent ioto Ihe higher regions of Ihe air,
as Ihe better paff.lge. His eleélrical apparalus, ~hou~h
communicating widl the eanh, has frequently, 10 1'10'
Icnt Ihunder·llorms, gil'en el'ide~1 Cparks lO his finger.
In the enumeration of the clfeéls of Ihunder·fiorms, he
obfw'es Ihat a I~ind always blows from the placc from
\Vhich Ihe Ihunder·clond proceeds ; Ihat Ihis is 'greeable
10lhe obCerl'ations of all mariners, anel thal the\Vind is more
or leCs violent in proponion tOthe fnddcnnefs cf the ap'
pearance of the thunder·cloud, the rapidity of its ex'
panfion, and the velocity \Vith which the acl!'eititious
clouds join it. The fudJen condcnf:,tion of fuch.a pro·
digious qnantilY of vapours muH diCplace the alr, and
r~pd it on al! fiJes.
He, in fome mearure imitated even thiselieél of Ihun'
der, at leaO produccd ~ circulation of .11 Ihe!i in his
room, by Ihe cominued clellrificalionof his chalO.
Among olherelfeas of lightning, he mentions the caCe
nf aman rendcred excecdlng Ililr. prefentl)' afler he was
Ilrurk dead in a fiorm of thunder. ~ut Ihemoll remark·
able circumfi<nce, in this caCe, was the lightning (cfihe.
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