B74 PHILOSOPHY OF ZOOLOGY. 
The influence of the nerves in the production of the 
electrical shock has been examined with care by Mr Top, 
and the results which have been published * throw consi- 
derable light on the mysterious process. He made an in- 
cision on each side of the cranium and gills of a lively tor- 
pedo, and pushed aside the electrical organs so as to expose 
and divide their nerves. ‘The animal was then placed in a 
bucket of sea-water. On examining it in about two hours 
afterwards, he found it impossible to elicit shocks from it 
by any irritation ; but it seemed to possess as much activity 
and liveliness as before, and lived as long as those animals 
from which shocks had not been received, and which had 
not undergone this operation. ‘Two of these animals being 
procured, the nerves of the electrical organs of one of them 
were divided after the manner above described. 'They were 
placed each in separate buckets of sea-water, and allowed to 
remain undisturbed. 'This was performed in the morning ; 
and, when examined in the evening, it was impossible to 
distinguish between the liveliness or activity of either. Of 
other two of these animals, the nerves of the electrical or- 
gans of one of them were divided. Being placed each in 
separate buckets of sea-water, they were both irritated as 
nearly alike as possible. From the perfect animal, shocks 
were received: after frequent repetition, it became weak 
and incapable of discharging shocks, and soon died. The 
last shocks were not perceptible above the second joint of 
the thumb, and so weak as to require much attention to 
observe them. From the other, no shocks could be receiv- 
ed: it appeared as vivacious as before, and lived until the 
second day. This experiment was frequently repeated, 
with nearly the same results. The nerves of one electric 

“ Phil. Trans. 1816, p. 120.—Ibid. 1817. p. 32. 
