34 



after which, the air was examined. When nsing r 

 atmospheric air, they found the quantity of nitro- 

 gene gas entirely undiminished, and the consumed 

 oxygen gas compensated by carbonic acid gas, 

 just as in man. They then caused these animals 

 to respire pure oxygene gas, in an apparatus, so 

 constructed, that the respired gas could be ex- 

 changed for new, and that, in which the animal 

 had respired, be separated for examination. 

 This was found to contain a large proportion of 

 nitrogene gas, which, however, was decreased 

 more and more in the succeeding portions, They 

 now mixed 78 parts of pure hydrogene gas with 

 22 parts of oxygene gas; and in this artificial 

 atmosphere, they confined a guinea pig for an 

 hour, having previously ascertained the volume 

 with minute exactness, and the same result was 

 again obtained: the expired air was mixed with 

 nitrogene gas, in a decreasing proportion ; but, 

 the quantity of nitrogene gas, obtained in this 

 manner, exceeded, in some experiments, the bulk 

 of the animal. They found, besides this, that 

 the animals, after the lapse of an hour, became 

 sleepy, without any perceptible sign of illness; 

 and that, during this period, less carbonic acid 

 gas was produced. As in these experiments, more 

 aitrogene gas was exhaled, than the fluids of the 



