us and incomparable Mr.
_Boyle_, published in his deservedly famous Pneumatick Book, the weight of
Quicksilver, to that of the Air here below, is found neer about as fourteen
thousand to one: If we suppose the parts of the _Cylinder_ of the
_Atmosphere_ to be every where of an equal density, we shall (as he there
deduces) find it extended to the height of thirty five thousand feet, or
seven miles: But because by these Experiments we have somewhat confirm'd
the hypothesis of the reciprocal proportion of the Elaters to the
Extensions we shall find, that by supposing this _Cylinder_ of the
_Atmosphere_ divided into a thousand parts, each of which being equivalent
to thirty five feet, or seven geometrical paces, that is, each of these
divisions containing as much Air as is suppos'd in a _Cylinder_ neer the
earth of equal diameter, and thirty five foot high, we shall find the
lowermost to press against the surface of the Earth with the whole weight
of the above mentioned thousand parts; the pressure of the bottom of the
second against the top of the first to be 1000 - 1 = 999. of the third
against the second to be 1000 - 2 = 998. of the fourth against the third to
be 1000 - 3 = 997. of the uppermost against the 999. or that next below it,
to be 1000 - 999 = 1. so that the extension of the lowermost next the
Earth, will be to the extension of the next below the uppermost, as 1. to
999. for as the pressure sustained by the 999. is to the pressure sustain'd
by the first, so is the extension of the first to the extension of the 999.
so that, from this hypothetical calculation, we shall find the Air to be
indefinitely extended: For if we suppose the whole thickness of the Air to
be divided, as I just now instanced, into a thousand parts, and each of
those under differing Dimensions, or Altitudes, to contain an equall
quantity of Air, we shall find, that the first _Cylinder_, whose Base is
supposed to lean on the Earth, will be found to be extended 35-35/999 foot;
the second equal Division, or _Cylinder_, whose _basis_ is supposed to lean
on the top of the first, shall have its top extended higher by 35-70/998
the third 35-105/997 the fourth 35-140/996 and so onward, each equal
quantity of Air having its dimensions measured by 35. and some additional
number exprest alwayes in the manner of a fraction, whose numerator is
alway the number of the place multipli'd by 35. and whose denominator is
alwayes the pressure of the _Atmosphere_ s