, . • [ i8 7 ] 
in their quantity, they equally precipitate in lime- 
water, and they are redored by the fame means. 
Since air which has palled through the lungs is the 
fame thing with air tainted with animal putrefa&ion, 
it is probable that one ufe of the lungs is to carry off 
a putrid effluvium, without which, perhaps, a jiving 
body might putrefy as foon as a dead one. 
, "When a rnoufe putrefies in any given quantity of 
air, the- bulk of it is generally increafed for a few 
days ; but in a few days more it begins to (brink up, 
and generally, in about eight or ten days, if the wea- 
ther be pretty warm, it will be found to be diminifhed 
or -L of its bulk. If it do not appear to be di- 
minifhed after this time, it only requires to be palled 
through water, and the diminution will not fail to 
be fenfible. I have fometimes known almo.ft the 
whole diminution to take place, upon once or tv/ice 
paffing through the water. The fame is the cafe 
with air, in which animals have breathed as long as 
they could. Alfo, air in which candles have burned 
out may almoft .always be farther reduced by this 
means. All -thefe procefies, as I obferved before, 
feem to difpofe the compound mafs of air to part 
with fome conftituent part belonging to it; and this 
being mifcible with water, mud be brought into 
contact with it, in order to mix wdth it to the 
mod advantage, elpecially when its union with the 
other conftituent principles of the air is but partially 
broken. 
I haveputmice into veffels which had theirmouths 
immerfed in quicldilver, and obferved that the air 
was not much contradied after they were dead of 
.cold; but upon withdrawing the mice, and admitting 
B b z lime 
