110 ADDITIONAL NOTES. 



conditions, qu'on pourrait desirer pour le succes 

 de 1'experience." 



In using this apparatus, it has been seen that 

 I employed rabbits of nearly the same size, occu- 

 pying the space of from 48 to 50 cubic inches. 

 My three first experiments were intended to de- 

 termine the quantity of carbonic acid exhaled 

 from the lungs of rabbits of this size, breathing 

 under natural circumstances. In one of them 

 it proved to be 25*3 cubic inches, in each of the 

 others 28*22 cubic inches in half an hour, giving 

 an average of about 27*25 cubic inches of carbonic 

 acid in this space of time. In my third experi- 

 ment, a rabbit, in which the spinal chord, nerves, 

 and vessels had been so divided as to produce the 

 same effect as decapitation, the circulation having 

 been afterwards maintained by artificial respira- 

 tion, generated 20*2 cubic inches in half an hour. 

 The formation of carbonic acid was, therefore, 

 less than that by the animal in its natural condi- 

 tion, in the proportion of about 20 to 27. But in 

 this experiment an amount of haemorrhage took 

 place, which, although immediately suppressed, 

 seemed to afford a sufficient explanation of the 

 difference. In order to avoid this source of error, 

 my subsequent experiments were made in a way 

 in which no loss of blood could ensue, the functions 

 of the brain being destroyed, not by any mecha- 

 nical operation, but by means of a narcotic poison. 

 The result was, that the carbonic acid generated 

 was fully equal to that which rabbits of the same 

 size supply under natural circumstances. 



