316 Supposed Agency of Galvanism in transferring Colors, §c. 
Arr. X.—Supposed Agency of Galvanism in transferring Colors 
through animal substances ; in a letter from Dr. ALEXANDER 
Jones, of Athens, (Geo.) to Geo. W. Carpenter, of Philadelphia. 
(Communicated for this Journal by G. W. C.) 
Havine seen it stated in a Jate number of the American Journal 
of Medical Sciences, that, if a fluid colored blue, was inclosed with- 
ina bladder, and then immersed in another fluid colored red, that on 
standing for some hours, it was found that a portion of its coloring 
matter had found its way through the coats of the bladder, and had 
mixed with the red fluid, while a portion of the red fluid had passed 
from without into the bladder and mixed with the blue fluid, thus 
demonstrating that two currreuts had been formed through the blad- 
der. Reflecting on the cause of this double transposition of the col- 
oring fluid, | was led to believe, if the experiment was true, that 
it depended probably on galvanic agency : that one colored fluid was 
positive, while the other was negative; and that a change of position 
took place, the process of which might be called electrical percola- 
tion. ‘The experiment appeared so interesting to me, that I deter- 
roined to repeat it in various ways. . For this purpose I formed a vol- 
taic pile of about forty pairs: between the wires of the negative and 
positive pole I placed three wine glasses. ‘T'wo of the glasses in 
which the positive and negative ends of the wires were made to ter- 
minate, were nearly filled with clear water. The middle glass was 
filled with an infusion of cochineal. I also inclosed a small quantity 
of an infusion of litmus in a piece of beef’s bladder, which was se 
curely tied and immersed in the middle glass, containing the infusion 
of cochineal. I connected the glasses by means of small pieces of 
brass wires. Ina short time I found that a portion of the enclosed 
infusion of litmus had found its way through the coats of the bladder, 
and commingled with the infusion of cochineal on the sides of the 
bladder next the negative pole. I removed the pieces of wires, and 
connected the glasses with moistened strips of beef’s bladder. In 
two or three hours I found a portion of the litmus coloring matter 
had passed through the connecting slip of bladder, and collected 
the negative wine glass of clear water, so far as to communicate to t 
a sky blue tinge. The clear glass of water at the positive pole, ot 
‘mained unchanged in color: on adding a small quantity of s . 
acid to the negative glass, it was changed to a pale red, proving the 
presence of the litmus color. On opening the piece of bladder en- 
closing the infusion of litmus, I found it had assumed @ reddish of 
