160 



128. The results of Mr Davy's experience, how- 

 ever, do not correspond with theso conclusions of 

 Lavoisier. He introduced a mouse into a jar con- 

 taining an atmosphere composed of 10.5 cubic inch- 

 es of oxygen, and three inches of nitrogen gas. In 

 half an hour, the animal appeared to suffer much, 

 and, in about an hour, lay down on his side, as if 

 dying : in an hour and a quarter he was withdrawn 

 from the jar alive, but motionless. The residual 

 air, on being analysed, was found to have lost only 

 2.1 cubic inches of its oxygen gas, and consequent- 

 ly 8.4 inches of that gas still remained. Another 

 mouse, which was put at the same time into a jar 

 containing 15.5 cubic inches of atmospheric air, was 

 taken out through the mercury alive, but unable to 

 stand, in 5O minutes : and on analysing the residual 

 air, 2.7 cubic inches of its oxygen were consumed. 

 Hence it appears, that the mouse in atmospheric air 

 consumed nearly one-third more of oxygen in 5() 

 minutes, than the other mouse did in an hour and a 

 quarter, when placed in a jar containing so large a 

 portion of oxygen *. The results of these experi- 

 ments on mice are corroborated by those made by 

 Mr Davy on his own respiration ; for he found, 

 that he consumed much less oxygen gas when he 

 respired it pure, than when, for the same length of 

 time, he breathed atmospheric air ; and the quantity 

 of carbonic acid formed in the first case, was but 

 little more than half that obtained by the respiration, 

 for the same time, of atmospheric air t- These ex- 



Davy's Researches, p. 4 1 f Ibid. p. 442. 



