[ x 9i J 



either itfelf extinguish flame, or has in it inch a mix-' 

 ture of fixed air, as to give it that property. 



That the putrid effluvium will mix with water 

 feems to be evident from the following experiment. 

 If a moufe be put into a jar full 1 of water, ftanding 

 with its mouth inverted in another veffel of water, a 

 confiderable quantity of elaftic matter (and which 

 may, therefore, be called air) will foon be generated, 

 unlefs the weather be fo cold as to check all putre- 

 faction. After a fliort time, the water contracts an 

 extremely fetid and offenfive fmell, which feems to 

 indicate that the putrid effluvium pervades the water,, 

 and affects the neighbouring air j and fmce, after this, . 

 there is often no increafe of the air, that feems to be- 

 the very fubftance which is carried off through the 

 water, as fart as it is generated; and the offenfive 

 fmell is a fufficient proof that it is not fixed air. For 

 this has a very agreeable flavour, whether it be pro- 

 duced by fermentation, or extracted from chalk by 

 oil of vitriol ; -affecting not only the mouth, but 

 even the- noftrils, with a pungency which is pe- 

 culiarly plealing to a certain degree, as any ptrfoii i 

 may eaiiiy fatisfy himfelf who will chufe to make 

 the experiment. If the water in which the monfe 

 was immerfed, and which is faturated with the pu- 

 trid air, be changed, the greater part of the putrid ■ 

 air- will, in a day or two, be abforbed^ though the 

 moufe continues to yield the putrid effluvium as be- 

 fore; for as foon as this frefh water becomes faturated 

 with it, it begins to be offenfive to the fmell, and 

 the quantity of the putrid air upon its fur face- increa* 

 fe-s as before. I kept a moufe producing putrid Vir in. 

 this manner for the fpace of feyeral .months, , 



Six., 



