16 ON THE INFLUENCE 



action of the heart ceases, only because respira- 

 tion is under its influence, and if under these 

 circumstances respiration be artificially produced, 

 the circulation will still continue. 



3. When the influence of the brain is removed 

 the secretion of urine is suspended, and no heat 

 is generated; notwithstanding that the func- 

 tions of respiration, and the circulation of the 

 blood, continue to be performed, and the usual 

 changes in the appearance of the blood are pro- 

 duced in the lungs. 



4. When the air respired is colder than the 

 natural temperature of the animal, the immediate 

 effect of respiration may be not to generate, but 

 even to diminish animal heat.* 



* In the original publication a postscript was added to the 

 Croonian Lecture, detailing an experiment which shewed 

 that carbonic acid was generated in considerable quantity 

 during the respiration of a decapitated animal. This is 

 omitted on the present occasion, the necessity for introducing 

 it being superseded by the more exact experiments related 

 in the following paper. 



