114 ELECTRIC FOECE CHAP. X. §. I. 



the fingers of the other hand were used in a similar 

 manner. The fingers last introduced were not 

 always positive or negative to the others. Keeping 

 the fingers in, then moving one of the fingers so as 

 to make the fluid rise and fall upon the surface of 

 the electrode in the vessel, produced hut little 

 motion of the needle. After the fingers had heen in 

 for some time, and the needle had hecome quite 

 stationary, upon contracting the muscles of one arm 

 an effect occurred upon the needle indicating the 

 contracted arm to be positive to the other 3°; by 

 contracting the muscles of each arm alternately, the 

 effect amounted to 5°. The result was definite, and 

 the motion of the needle steady. 



Du Bois Eeymond" considers that there are five 

 circumstances as influential in producing a current : 

 viz. Is*, temperature inegale; 2nd, Anree inegale de 

 ITiumectation avec le liquide conducteur; 3rd, tension 

 inegale de la peau ; ith, lesion de I'une des places de 

 la peau; 5th, transpiration inegale. I could not 

 refer the effects that were obtained to either of these 

 circumstances; to the tension of the skin, for 

 instance. 



Three solutions were now prepared; the first 

 consisting of a concentrated solution of common 

 salt ; the second of sulphuric acid, one part of strong 

 acid to six parts of water ; and the third of one part 

 of liq. potassse (Pharm. Lond.) to four parts of 

 water. 



" Biblioth^que Universelle de Geneve, Jnin 1883. 



