TOrvPEDO. 125 



he remarked thai; after death no other sensation proceeded from 

 it than might come from any other fish. Redi made the trial 

 of placing his hand in the water in which the fish lay, but 

 ■without feeling any inconvenience; as might be expected if tlie 

 fish were not irritated. This author detected the existence of 

 what we now know to be the electric organs; but he failed 

 to understand their mode of operation, and supposed the columns 

 to be of the nature of muscles. 



The operations of Mr. Walsh were conducted under more 

 favourable circumstances, in consequence of the discoveries that 

 had been lately made in the science of electricity. The 

 substance of them was, that the fish possessed the power of 

 accumulating in its electrical organs a considerable amount of 

 that fluid, much in the same manner as it is accimiulated in 

 the instrument called the Ley den phial; so that while one of its 

 surfaces, the back, was in the positive condition, the belly was 

 negative; and the equilibrium could be restored by the inter- 

 position of water, metals, or the human body. Besides the degree 

 of pain and numbness inflicted by this voluntary discharge on 

 the part of the fish, under the influence of its will or passion, 

 its violence can be judged by what is reported by Lacepede: 

 that a duck was presently killed by being exposed to the shock. 

 In Mr. Walsh's experiment a Torpedo was laid on a table, 

 where it rested on a wet napkin. Five persons, insulated, or 

 separated from any connection with a conducting substance, 

 stood round another table; and two brass wires, each thirteen 

 feet long, were suspended by silk strings from the ceiling of 

 the room. One of these wires rested by one of its ends on the 

 wet napkin, and the other end was immersed in a basin of 

 water placed on a second table; on which stood four other 

 basins, also full of water. The first person placed a finger of 

 one of his hands in the water in which the wire was immersed, 

 and a finger of his other hand in the second basin; and so on 

 successively until all the five persons were brought into com- 

 munication with one another by means of the water in the 

 basins. One end of the second wire was dipped into the last 

 basin of water, and with the other end ^Ir. Walsh pressed the 

 back of the fish; at which instant the whole of the five persons 

 were affected with the shock. Nothing could have been more 

 decisive, even if the electric machine had been itself employed. 

 VOL. I. T 



