122 ELEOTBIC FORCE CHAP. X. §. I. 



The results of these experiments tend to establish 

 the following conclusions, viz. 



First. That during muscular contraction in man 

 and in frogs, an effect upon the galvanometer may 

 be obtained indicating the manifestation of an electric 

 current. 



Secondly. That this manifestation of an electric 

 current is due, in a great measure, to secondary 

 reactions, viz. between the animal secretions and the 

 solutions on the one hand, and between the solutions 

 and the platinum electrodes on the other ; but that 

 there nevertheless- remains a residual effect which 

 cannot be referred to either of these actions, or to 

 those pointed out by Do Bois Keymond. 



Concluding Remarks. 



The numerous instances in which an electric 

 current may be shewn to exist, naturally renders 

 any conclusion deduced from results obtained by 

 means of the galvanometer extremely doubtful. If 

 these remarks are applicable to physical researches, 

 where we have such control over om' experiments as 

 to afford us facilities favourable for eliminating 

 sources of error, how easily may we conceive that 

 they would apply with far greater force to phy- 

 siological researches devoid of such facilities. The 

 strong prejudices which exist in reference to electro- 

 physiological inquiries cannot therefore be a matter 

 of much surprise, but must create a great difi&culty 

 to any individual who shall attempt the elucidation 



