AND OBSERVATIONS ON THE TORPEDO. 
269 
The effect of the electricity of a small voltaic trough, the shock of which I 
could just perceive at the extremities of the moistened fingers, was very distinct 
on the voluntary muscles of a live torpedo just taken from the water; but it 
did not appear to affect in the least the electrical organs. I could not perceive 
the slightest contraction of them in whatever manner the wires were applied, 
not even when a minute portion of integument was removed, or when one of 
the wires was placed in contact with a fasciculus of the electrical nerves. 
Even after apparent death many of the parts decidedly muscular continued to 
contract under this stimulus, especially the muscles of the flank and the cross 
muscles of the inferior surface of the thorax and the heart; indeed this latter 
organ, two hours after it had been removed from the body, and had ceased to 
contract spontaneously, renewed its contractions under the galvanic influence. 
Other stimulants have been applied to the electrical organs, and with the same 
negative result. Even when punctured and incised, (a portion of their skin 
having been removed, which appears to be very sensitive,) no indications what¬ 
ever were witnessed of their substance being either sensitive or contractile. 
Reflecting on the facts and observations which I have just detailed, it appears 
to me very difficult to resist the conclusion, that the electrical organs of the 
torpedo are not muscular, but columns formed of tendinous and nervous 
fibres distended by a thin gelatinous fluid. Their situation too, surrounded 
by and exposed to the pressure of powerful muscles, shows that if condensation 
is required for the exercise of the electrical function, they may experience it 
without possessing any muscular fibres in their own substance. The arrange¬ 
ment of the muscles of the back and of the fins, and of the very powerful cross 
muscles situated between the under surfaces of the electrical organs, is admi¬ 
rably adapted to compress them. Without entering into any minute anato¬ 
mical examination of these muscles and their uses, it is only necessary to com¬ 
pare them in the torpedo and in any other species of Ray, to be convinced that 
they are adequate to and designed for the effect mentioned. 
Mr. Hunter, in his account of the torpedo *, describes the columns of the 
electrical organs as composed of cells containing a fluid, divided by their hori¬ 
zontal partitions, which he was able to count. This structure seems very pro¬ 
bable, and in the specimens I dissected at Rome, I saw vvhat I fancied an 
MDCCCXXXII. 
* Phil. Trans. 1773. 
2 N 
