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Further Experiments and Observations on the influence of the Brain on 

 the generation of Animal Heat. By B. C. Brodie, Esq. F.R.S. Com- 

 municated to the Society for promoting the knowledge of Animal Che- 

 mistry, and by them to the Royal Society. Read June 18, 1812. 

 [Phil. Trans. 1812, p. 378.] 



In some former experiments it was found, that in an animal from 

 whom the head was removed, the circulation of the blood might be 

 maintained by means of artificial respiration ; that under these cir- 

 cumstances the blood underwent the usual changes of colour in the 

 two capillary systems, and carbonic acid was evolved from the lungs, 

 but no heat was generated, and the animal cooled more rapidly than 

 a dead animal of the same size. In the present communication, some 

 experiments are detailed, which were instituted with a view to the 

 further elucidation of this subject. 



An apparatus was constructed for the purpose of measuring the air 

 consumed in respiration ; and two series of experiments were insti- 

 tuted, the first to ascertain the quantity of air consumed by animals 

 breathing under ordinary circumstances ; and the second to ascertain 

 the quantity consumed by animals which are made to breathe arti- 

 ficially after the functions of the brain are destroyed. It was found, 

 that in animals breathing under these different circumstances, there 

 is little or no difference in the quantity of oxygen which disappears, 

 and of carbonic acid, which is evolved in a given space of time ; but 

 that it uniformly happens, that where the functions of the brain are 

 suspended, no heat is generated; and that the animal cools more 

 rapidly than a dead animal. 



In another experiment, an animal apparently dead from the poison 

 of essential oil of almonds, was made to recover, by respiration being 

 artificially produced until the poison had ceased to exert its influence. 

 It was found, that while the functions of the brain were suspended, 

 no heat was generated, but that as the sensibility of the animal was 

 restored, the power of generating heat returned. 



These experiments, as well as those detailed in the Croonian Lec- 

 ture for 1810, go far towards proving that the temperature of warm- 

 blooded animals is considerably under the influence of the nervous 

 system ; but, what is the nature of the connexion between them ? 

 Whether the brain is directly or indirectly necessary to the genera- 

 tion of animal heat ? These are questions which, in the present state 

 of our knowledge, must remain unresolved. 



On the different Structures and Situations of the Solvent Glands in the 

 digestive Organs of Birds, according to the nature of their Food and 

 particular Modes of Life. By Everard Home, Esq. F.R.S. Read 

 June 18, 1812. [Phil. Trans. 1812,^. 394.] 



Since the solvent glands in birds are larger than in quadrupeds, 

 Mr. Home has investigated their structure in different classes of 

 birds, and has here collected several varieties that he has observed ; 



