Alison on the Nerves. 107 



shape of nervous influence or energy. And the difference be- 

 tween the two sets of muscles, has been referred by some to the 

 different parts of the nervous system, from which their respec- 

 tive portions of energy have been conceived to be derived. 

 Thus Willis and Boerhaave derived the energy of the voluntary 

 muscles from the brain, and of the involuntary from the cere- 

 bellum ; Whytt and Cullen, that of both from the brain gene- 

 rally ; Bichat, that of the former from the brain, and that of the 

 latter from the ganglia of the sympathetic nerve; Le Gallois, 

 that of the former set of muscles from the nerves immediately 

 supplying them, and that of the latter from the spinal marrow ; 

 and, in some late French physiological works, reference is made 

 to an opinion of Reil, which may perhaps be considered as the 

 last hold of the doctrine of nervous energy, namely, that all 

 muscles derive their irritability from the coats of the nerves 

 immediately supplying them. 



These opinions have led to much false reasoning in regard to 

 the nature of various diseases ; and therefore it is of the utmost 

 importance to medical science, that we should be in possession 

 of facts illustrating the true nature of the connexion between 

 the nervous system, and the different muscular actions which 

 constitute so important a part of all the functions of the living 

 body. The experiments and observations of Dr. Wilson Philip 

 on this subject, agree perfectly with those recorded by Haller, 

 in his Elements of Physiology, and in his long controversy with 

 Dr. Whytt, and appear to place beyond all doubt the general 

 correctness of the doctrines which he taught in this fundamental 

 department of physiology. 



The following may be stated as the most important proposi- 

 tions which these physiologists have established. 



1. " That the power of the muscles, both of voluntary and 

 " involuntary^motion, is independent of the nervous system ;" 

 that is, that no muscle, voluntary or involuntary, derives any 

 thing from the nervous system, which enables it to contract. 

 And, therefore, that the term nervous influence or energy in this, 

 the most common sense in which it is employed in physiolo- 

 gical and medical writings, is absolutely without a meaning. 



