112 ELEOTEIO FORCE CHAP. X. §. I. 



Eetmond', it would appear, that the direction of the 

 current due to muscular contraction, is inverse, i. e. 

 from the hand to the shoulder. 



Several other experiments were undertaken, in 

 which different solutions were employed to moisten 

 the hands; the effect upon the needle was now 

 much greater. When one hand was moistened with 

 a weak alkaline solution and the other with water, 

 upon contracting the muscles of the arm holding 

 the alkaline electrode, this became negative to the 

 other; but by proper management, by not having 

 the solution too strong, this arm could be made to 

 become positive, the current occurring during mus- 

 cular contraction overcoming the influence of the 

 alkaline solution. Feeling the force of the objections 

 that might be raised in reference to the use of the 

 metallic electrodes, I do not think it necessary to 

 relate any other experiments in which these instru- 

 ■ ments were used. 



A galvanometer" of the following construction 

 was now employed. It consisted of two coils, placed 

 one above the other so as to produce the full effect 

 upon both needles, with an index to indicate the 

 amount of deflection. Each coil was Synches in 

 length, and the same in breadth, consisting of 1 500 



' Rapport sur les Memoires r^latifs aux ph^nomfenes electro- 

 physiologiques pr^sentfes k I'Acad^mie par M. E. du Bois- 

 Eeymond, Comptes Eendus, vol. xxxi. p. 38. 



■" Vide Faraday's mode of employing a galvanometer. Phil. 

 Trans. Series xxviii. 1853. 



