[ *79 ] 



the place of common air for the purpofe of ignition, 

 which is analogous to other experiments with 

 nitre. 



Having had the curiofity, 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; 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 flxong 

 inflammable air in a glafs jar, {landing 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 ; and finding that the remainder made an 

 efFervefcence with nitrous air, I concluded that it 

 mufl 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 vefiel containing 2§ 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 

 k to be fo when a moufe has actually died in it. 

 A a 2 Inflam- 



