166 



PHYSIOLOGY OF MUSCLES AND NERVES. 



of the multiplier were connected with two trou^^hs or 

 vessels of cast zinc, the outer surfiices of which had 

 been lacquered, while the inner cavity had been care- 

 fully amalgamated. A solution of sulphate of zinc was 

 poured into this cavity, and pads, formed of many folds 

 of blotting-paper saturated with the same solution, were 

 folded over the edge of the vessels in such a way that 



Fig. 39. Homogeneous diverttxg vessel, as ised by E. du Bois- 



Keymond. 



part was immersed in the solution, part protruded over 

 the edges, and these pads end in a sharply cut cross 

 section. Small discs of an isolating substance (vulca- 

 nised india-rubber), with the help of caoutchouc bands, 

 retained the pads in their places. The vessels being 

 pushed toward each other till the pads touched, or the 

 intermediate space between the pads being bridged by a 

 third pad, also saturated with a solution of sulphate of 

 zinc, the needle of the multiplier continued unmoved, 



