[ 286 j 
paradox, that heat fhould any where condenfe. I 
have already hinted at the folution. Heat doth 
not condenfe any finite mafs of matter, which is 
at liberty, on all tides, to expand itfelf ; but ailing 
on a finite mafs, which hath not unlimited liberty 
of expanfion, it may condenfe one part by the rare- 
faction of another. Ailing on an infinite mafs, it 
muft do this ; becaufe it can only tranfpofe. It 
neither generates new matter, nor annihilates what 
already is. What is taken therefore from one part, 
muft be added to another, and vice verfd j other- 
wife the quantity of matter, in the whole, muft be 
changed. 
Imagine A BCD to be a fmall portion of any 
orb of the atmofphere (fig. 8.) AEFB, CMND, 
CHGA, DLBK, contiguous portions. Heat drives 
many of the particles, which occupy the fpace ABCD, 
out of it ; but it likewife drives out many of the par- 
ticles which occupy the contiguous (paces. And 
of thofe which are driven out of the contiguous 
fpaces, many will enter the fpace ABCD. If the 
particles which are driven into ABCD, be more in 
number than thofe which are driven out of it, the 
air, in this fpace, is condenfed, by that very caufe, 
which would rarefy it, if the contiguous portions 
were annihilated. Thus condenfation in one part 
may, in an infinite fluid, muft enfiae from rare-, 
faction in another, if the quantity of matteT re- 
mains unaltered. Where then is the wonder, that 
the like effeCt fhould follow from the caufe of 
rarefaction combined with other caufes ? 
8. fhe cafes in which L jails below B, or above 
the fur face ^ Jeem to be phyficalf impoJJ.ble i without 
an 
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