OF DIGESTION. (>27 



nervous influence is not essential to the process, 

 (further than as it governs the voluntary function 

 of respiration,) has been sufficiently proved by 

 the experiments of Brodie, Magendie, C. Holland, 

 Mayer, Braschet, Leuret, and Lassaigne, who 

 have shown that in the horse, dog, and rabbit, the 

 nerves going to the stomach may be divided with- 

 out arresting the secretion of gastric juice, or se- 

 riously retarding the process of digestion. 



Nor have we ever had the slightest proof that 

 electricity is essential to the process ; for the ex- 

 periments of Dr. Philip have been repeatedly 

 proved to be fallacious, and therefore require no 

 comment.* But that caloric is the principal agent 

 on which the solvent power of gastric juice de- 

 pends, would appear from a variety of considera- 

 tions. 1. We have seen that digestion is far more 

 rapid in birds than in mammalia, and more rapid 

 in the latter than in cold blooded animals. 2. It 

 has been proved by the experiments of Dr. Beau- 



* The impression that electricity is in some way connected with 

 digestion and all other vital phenomena, has been inferred from 

 the fact, that the Gymnotus, Torpedo, and Silurus, have the 

 power of communicating an electrical shock ; and that after hav- 

 ing imparted several shocks, the power of digestion is greatly di- 

 minished. But the circumstance alone of this power being con- 

 fined to a very small number of animals, and these of a low grade 

 in the scale of organization, proves that it is not essential to any 

 of the vital functions, that like the nauseous secretion of the pole- 

 cat, and that of some insects, it was intended by nature merely 

 as a means of defence. Besides, electrical fishes have always 

 been found in warm climates, and cannot exert their peculiar fa- 

 culty when exposed to a low temperature. It was observed by 



