262 Wilson Philip on the 



the existence of a power capable of the most complicated functions 

 of the nervous influence, yet distinct from it, than admit the iden- 

 tity of these powers ; and that, without attempting to shew that in 

 any of their properties they are incompatible with each other ; an 

 instance of more erroneous reasoning than which it would, as far 

 as I am capable of judging, be impossible to adduce ; or that 

 galvanism excites the nerves of the part to prepare nervous in' 

 flu,ence, and thus perform the office of the brain or spinal mar- 

 row, of which every fact relating to their functions proves them 

 incapable. We might as well, I conceive, suppose a bone, as a 

 nerve capable of preparing this influence. They are mere 

 channels through which it passes, and when the little they re- 

 tain after their separation from the brain and spinal marrow is 

 exhausted, they have no capability of forming more. Dr. Alison, 

 far from adopting eitlier of these opinions, declares without 

 hesitation, that the only way of refuting my inference is to 

 prove that the nervous influence is not essential to secretion. 

 " Here we have," he observes, " the nervous influence cut off, and 

 yet secretion going on. On the supposition that the nervous 

 influence is really essential to secretion, this can only be ex- 

 plained by supposing the galvanic influence which is substi- 

 tuted for it to be really the same thing. If, therefore, we can 

 make it probable that the changes which occur in the nervous 

 system are not galvanic actions, we need go no farther after 

 these experiments in order to shew that the nervous system is 

 not necessary to secretion:" and in page 119, " if they," that 

 is the changes in the nervous system, " be not galvanic, 

 Dr. Wilson Philip's experiment, above referred to, becomes 

 an experimentum crucis against their being essential to secre- 

 tion," 



of the non-galvanized rabbit contained only a continuous mass of masti- 

 cated parsley." He closes his account of this experiment with the follow- 

 ing observations : " From this experiment it seems legitimate to infer, that 

 galvanism of a certain power passed in a continued stream through the 

 thoracic ami gastric portions of the eighth pair of nerves, after their divi- 

 sioHj will produce the phenomena of digestion. It entirely corresponds, 

 both in its details and results, with the experiments of Dr. \Vilson Philip." 



