344 J. Trowbridge— Electro-motive action of Liquids. 
In fig. (1) T and T’ represent terminals of the galvanometer 
in plan. I found that when the extremities of the U tube 
were placed along the line A C, a current went from 0 toA 
through the U tube, arising probably from the resultant electro- 
motive action at A and C, between the fluid enclosed in the 
tube and the sulphate of zinc in the connecting vessel. 
ometer returned to zero, and oscillated over a few degrees. 
This may be explained by supposing that the current 
divides at B into nearly equal portions, one part taking the 
direction to the right and the other to the left, and counteract 
ing each other in their action upon the galvanometar. On 
turning the tube into the position a’ d’, the current is immed: 
ately reversed, the current which before passed in the direction 
O A through the galvanometer, now passing in the direction 0 
The same phenomena are repeated at D, when the tube has 
been turned 270° from the point A; the current running agail 
in the direction O A on a very slight movement of the tube 
from D toward A. : 
Care must be taken to eliminate the errors which arise from 
This current, however, can be readily distinguished from that 
€ experiments of Tomlinson on the cohesive figures P 
duced by different liquids readily occurs to one 1 eon 
these experiments. But there is not a close analogy yore 
the two classes of phenomena; for, upon touching the § a 
of the bath with a drop of colored liquid, the needle m i 
cases is deflected before the colored fluid reaches the ae 
ese experiments bear upon certain facts stated by writers 
electro-physiology. DuBois Reymond having connect re 
vessels containing the terminals of the galvanometer by ; 
phon tube containing the same liquid as was contained “th 
separate vessels, the ends of the tube having been cove 
u : n ' 
one arm violently, he found that the needle was deflected 
one direction, and upon contracting the other, the direction 7 
reversed. i 
: ie. 
This action is attributed by DuBois Rey mond : 
agi Aree NE Le ee Sy ae ee = 
