106 ADDITIONAL NOTES. 



firmed by those who assisted me on these occa- 

 sions ; and I do not doubt that those of M. Le 

 Gallois were equally correct. Dr. Wilson Philip 

 has pointed out what is probably one cause of 

 the difference between us, in the difference in 

 the quantities of air impelled into the lungs. In 

 a rabbit in which the lungs were inflated about 

 30 times in a minute (this being about the ordi- 

 nary number of respirations in a full-grown 

 animal of this species), the loss of heat was 

 greater than in the dead rabbit ; but when the 

 process was repeated only 12 times in a minute, 

 the proportion was reversed, and the dead animal 

 cooled somewhat faster than the other. 



One effect of the admission of cold air into the 

 lungs, whether by the natural process of respira- 

 tion, or by respiration artificially performed, 

 must be to carry off from the animal a certain 

 portion of heat ; and this effect must be produced 

 to a greater extent if, when respiration is arti- 

 ficially performed, a larger quantity of cold air 

 enters the lungs than that which they receive 

 under ordinary circumstances. It is difficult to 

 estimate the precise quantity of air which enters 

 the lungs when they are artificially inflated; 

 and I must therefore admit that one of the 

 conclusions which I ventured to draw from 

 my experiments, namely, that where the 

 influence of the brain is withdrawn, no heat 

 whatever is generated, may not be strictly and 

 rigidly correct. The difference, however, in this 

 respect between these two modes of respiration, 



