[ 2 6 9 ] 
my own part, I incline) is not to be too hadily 
adopted, upon the bare evidence of its arifing out 
of M. be luc’s formula j becaufe the general ex- 
tent of thele jormulre is more than experiment hath 
hitherto proved. And I (hew, by a very dmple 
inftance, that it is eafy to imagine other laws, be- 
tween the temperature and the eladicity, which, 
to all practical purpofes, would be the fame as 
M. de luc’s, within the utmofl limits of his ex- 
periments, and even beyond them, and yet differ 
from it in remote confeauences. 
x 
If M. de luc’s jormulce be univerfally and ftrifHy 
true, the confequence I have pointed out muft be ad- 
mitted ; and it will follow, that the force of eladicity 
owes its firft production and origin to temperature : or, 
at leaf!:, that the relation between heat and eladicity, 
if not the mod: intimate one of caufe and effect, is that 
which flands the next in the fcale of natural affi- 
nities, namely, that they are infeparable effects of 
fome common caufe. And thefe conclufions will 
hold, if the form of the general expredion be true. 
though the quantity of the equation 
require a correction : for 
n x 8 
B fhould 
T 5 "STT 
, 359 1 
a change ot the fraction 
will only alter the particular temperature, in 
which the fubtangent and elaflicity vanifh. 
3. The diminution of the airs dcnfty , as we 
ascend from the fnrface , is fubjedt to a limit. This 
limit is different, in different heights of the baro- 
meter, at the level of the fea, and even in a 
given height of the barometer, in various tempe- 
ratures. Bui the dendty even at an infinite height is 
never o, or infinitely lmall. In fig. 1. through 
C draw 
