[ *79 ] 
the place of common air for the purpofe of ignition, 1 
which is analogous to other experiments with 
nitre. 
Having had the curioflty, on the 25th of July 
1772, to expofe a great variety of different kinds of 
air to water out of which the air it contained had 
been boiled, without any particular view j the refult 
was, in feveral refpeCts, altogether unexpected, and 
led to a variety of new obfervations on the properties 
and affinities of feveral kinds of air with refpeCt to 
water. Among the reft three fourths of that which 
was inflammable was abforbed by the water in about 
two days, and the remainder was inflammable, but 
weakly fo. 
Upon this, I began to agitate a quantity of ftrong 
inflammable air in a glafs jar, Handing in a pretty 
large trough of water, the furface of which was 
expofed to the common air, and I found that when 
I had continued the operation about ten minutes, 
near one fourth of the quantity of air had difap- 
peared j and finding that the remainder made an 
effervefcence with nitrous air, I concluded that it 
muff have become fit for refpiration, whereas this 
kind of air is, at the firft, as noxious as any other 
kind whatever. To afcertain this, I put a moufe 
into a veflel containing 2f ounce meafures of it, and 
obferved that it lived in it twenty minutes, which is 
as long as a moufe will generally live in the fame 
quantity of common air. This moufe was even 
taken out alive, and recovered very well. Still alfo 
the air in which it had breathed fo long was inflam- 
mable, though very weakly fo. I have even found 
it to be fo when a moufe has actually died in it. 
A a 2 Inflam- 
