100 ANIMALS AND VEGETABLES _ III, 
otherwife, neither cold nor warm blooded ani- 
mals would live in fafety on mountains where 
the mercury falls lower than in barometers placed 
in clofe veflels (1). Animals can not only live 
in air which has loft its elafticity to fuch a 
degree that the barometer falls fome inches, as 
on the tops of lofty mountains, but in air, if 
it is renewed, where the barometer falls to lefs 
than half its natural height. Such is the inge- 
nious experiment of Sig. Cigna. ‘This acute ex- 
perimentalift confined two fparrows in the re- 
ceiver of an air-pump: one was left at liberty: 
the other put into a glafs bottle, around the neck 
of which a very large empty bladder was tied. 
Then he began to exhauft the air until the mer- 
cury, which ftood at twenty-feven inches and a 
half in the barometer, fell to nineteen. As much 
air was then returned to the receiver as deprefled 
the mercury two inches within. Ina fhort time 
afterwards, he drew the fame quantity from the 
receiver, 
(1) However, it is certain that animals removed from 
plains to mountains fuffer confiderably, though they may 
naturally live in fafety on the fummits of the higheft. M. 
de Sauflure afcended to the top of Mont Blanc ; the ba- 
rometer fell to 167, inches His refpiration was fo much 
affected and he was enfeebled to fuch a degree, that with 
great difficulty he could buckle his fhoe. Senebier, Memoire 
fur la vie et les ecrits de Horace Benedi@t de Sauffure.—T. 
