| N A l^ Ü R A L ' H I S T O R Y
was and thefeomnion air was very colq,;~ttie fpirit rofe much
at feveral'dep'ths in'the well; but -when the’Spirit ofrfhe Thértnemeter
ftbod highèf in the common 'aky^thè alteratiori'y^Tefs--: fat Feb.
25s," ‘3^702, ^(Experiment III.) when the Thermometer ftoodSH&wo
degrees below juft freezing, it role1 but five degrees, when$ufpénded
at twenty-oneTeet, for half an hour; and March*’ ro, 1702,;-(Experiment
8^-the Thermometer ftanding at two degrees below-juft
freezing, it role but feWur degrees though fülpended at'fixty'reet for
an hour; by which it is only plain, .that the" colder the Atmolphere,
the^greatër is-the difference between that* and the- rrifore even temperature
of the air below Ih the well, arid the Thermometer rifes
higher, but not in any given proportion to the depth; fo that what is-
here advanc’d cannot confirm the hypothefis now in queftion. That
vapour; or moift fteaiii; rifesTrom all waters, and"isf''iEiqêediidif-
perfed more or ï:lefs in all places, not only in places open* to the
Atmolphere, but in the clofeft rooms and the dcepeft cells of the
earth, is certainly true: Water -will eafily fly oif in-'e-Vaprifaflori,’
fometimes imperceptibly, - oftentimes, and' in cold -weather ufofe •
elpecially, vifible; as being condenfed into larger 'globules f by the
ambient cold; and Where there are fubtèrraneous heats occafióned
by the fomentation of Pyrites; Sulphur, Salt, an<T fuch mineral spro-
mbters of warmth, there this evaporation -isUcopiqus. gncf extra-1
ordinary, but ftiU not equal
and even immediate rivers which proceed at once from-'‘the bowels
o f the earth in feme places'; neither is?safere' ireafon'^to füppofë
fuch lubterraneous heats every where and at all tithes,- nothing being
more uncertain and unequal, than-the diftributiom of ;&dh igniting
mineral mixtures.. ’Tis reaforiable theft to i cbriGlttde; that the
lubterraneous heats which either refult fro'm the fermentations of
mineral mixtures, or from the equal diftribution of- fire through all.
matter, are not luffident where they are, nor conftantly • enough
found in any place, to fupply perennial fprings.1 The »grOundlefs
fancy of a central fire, and that mountains are alembieks in which
the vapours are- colleded and diftilled down their fides, is too chimerical
to need confutation.— -— Again, That perennial fprings
do owe their rife to rains and dews is difputed, and thought unlikely,
becaufe they do not feem to be at all affeded by the excels
or deficiency of either, let us confider therefore the nature of
fluids and the texture of the earth »together, and * fee- .whether
.perennial Iprings-may hot principally; be owing to |he waters of
the Atmofphere although neither increas’d-by heavy rains, nor‘fen-
fibly diminilhed by great droughts.
The earth mull not be looked upon as an abfolute dry mafs
exhibiting here and there its wonders in pouring forth a fpring
or fountain'where .there \^as|Etbywater before; the earth, is porous
in all itssparts; chinks an«‘ dudsi in‘ moll places, and; opens:
into Audc fubtc.i pint pus caverri^fajotlrers: Water is,perpetually
falling' andnirlimi.ati'rfeilitfelf öwhb gravitation? and fluidity
into the- hollb^slfil;;'Enefts> wit^^^^raifedt- M . fewer" into-.higher
gpbfitions’ atjradedhy falts of fanqs^®^ tranlpired in vapour, fo that fink
asl'deepï|a|? vie twill,l^wfe (find wateöpither a£ reft in* natural cavities^
or circulating'-from higher int® lower; chattels;fometimes in large:
currents, oftnerin fmafehreads. a™feil’ls, huh’in feme fhape, oe other
every wheref coafting through the veins of roefeor' clay, ’ till itr meets
with lueh fefiftance fsbm the?ftrata thablin is, forc’d feut through,
the feiPi'nlq, the open ^n^ Thi^Pf^t-he- generalriftate* .cm-thei partHy
and to continue this mbifture (without whichf|:he. earth ;muft foon
become; a dry faplefs cruft) fre£h flip,plies. M-d pérpetéally defcending
from gains’ andydetfs^and foalring lakes,
moralfes,?}five|,s,,^< andIferebks ;• where 'themaftagess, areiqfree and
jppeny the defeent is qnipk; and .the incteafd, of fprings eafily to
be perceived, but where -the ;chinksand+|&|T^’of |he?;tooky‘iftratn
are clofe, or a large horizontal, impenetrable“ rqckb intetppfes, of
where the^fallen mqifture is forced byl any1 ©drier obftacle to .take a
kujge- round t before it Gan fupply any conftant Ipring, ■ there prèfenb
Hidden fatin can have no vifible^e^^'^Jf the duds which colled:
^and"-. convey thèfëi Waters to Jneire apertures f’are long; ferpentmej
hind many, the-, Ipring fhews.; ndijwant o f - i n , • times;.,of
drought, becaufe of the many duds which ferve it;i nor<ai^^^re^fe
after heavy rainsy beeaiife-the chanels of its nourilhment aredqng,
winding, agd> require time, to reaeh the; fountain head: * Again, $
perènmal Iprings derive, their water Tas may . often be the qafe?) fi>oni
large caverns which alfo have their fupplies from rain, by .duds “ora
determined number and Certain dimenlions;. which aife neither con-
traded nor. dilated, then will the ftream be one* certain equable
quantity, let the feafen be ever fo wet and -rainy.„ If (hèffeafon be
extremely dry thefe caverns are capable of flipplying the perennial
Iprings to which they give rife, till frelh fupplies from rain, o||dew,
or bog arrive, which m u|; generally be the cafe before the 'caverns
are exhaufted. From this, Ihortview óf the •internal ftrudure..q£
the earth, it appears that’there is-hothing furprifing in Iprings -being
perennialfy^téy ^..nothing more than a collection of-Httle„yills,‘of
water, (as rivers are a colledipn óf bfoqks) which tendirig nearly
one Way are united, at laft, and break out into' öpen^if, and though
they owe not their immediate rife to the waters of;the Afrpolphere,
as the temporary occafiónal fprings do, yet proceed from duds and
refervoirs fed by the moifture of the adjacent ftrata, which moifture
primarily proceeds from fnow, 'hail, dews, and rain, though - more
I *• floWly