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XIV. Electro-Physiological Researches. — Sixth Series. Laws of the Electric Discharge 
of the Torpedo and other Electric Fishes — Theory of the production of Electricity 
in these animals. By Signor Carlo Matteucci, Professor in the University of 
Pisa, 8fc. Sfc. Communicated by Michael Faraday, Esq., F.R.S., fyc. &fc. 
Received May 20, — Read June 10, 1847. 
The present memoir is not a mere description of a certain number of facts lately 
discovered on the electricity of electric fishes ; besides this, and more than this, it 
contains the laws and theory of these phenomena. Consequently the order of expo- 
sition of the facts in this memoir will be the same as that which a scientific arrange- 
ment of the subject would dictate. 
It is needless to remind the reader that the discharge of the electric fishes is sub- 
ject to the will of the animal. 
On irritating any point of the body of an electric fish, it is easy to demonstrate by 
experiment that this irritation is transmitted by the nerves to the fourth lobe of the 
brain, and that then only the discharge takes place. If the spinal marrow be divided 
at any part of its length in a living torpedo, every kind of irritation below the point 
of section fails to produce any effect. 
It is equally easy to prove that the nervous action by which the discharge is deter- 
mined under the influence of the will, resides in the fourth, or electric lobe of the 
brain ; in effect, after the three superior cerebral lobes have been extracted, the tor- 
pedo can still give the shock either voluntarily, or from external irritations. 
We also know that if one of the electric organs of a living torpedo be rapidly de- 
tached, we can still obtain the discharge on irritating one of the nerves ramified 
within the organ. 
We have also shown, some time ago, that on acting upon these nerves with the 
electric current, we obtain the discharge under the same conditions and the same 
laws as those under which we have muscular contraction on acting upon the mixed 
nerves. Hence the remarkable analogy found to exist between muscular contraction 
and the electric discharge of fishes. 
The most singular and the most important fact in a theoretical point of view is the 
discharge which we obtain when we take a very small part of a prism of the electric 
organ of the torpedo, and irritate it in any manner. Electric discharges always take 
place, as is shown by the contractions of the galvanoscopic frog. 
I have very lately repeated this experiment in a variety of ways, and have always 
found that, on irritating one of the small nervous filaments distributed to the organ, 
