204 Memoir on the Torpedo as imitated by electricity 



It must be observed, that in trying this experiment, as my hands were out 

 of water, I could be affected only by that part of the fluid which passed 

 through my body from one hand to the other. 



420] The following experiments were made with the torpedo in air. 

 If I stood on an electric stool, and touched either surface of the electric 

 organs with one hand only, I felt a shock in that hand; but scarcely so 

 strong as when touching it in the same manner under water. If I laid a 

 hand on one surface of the electric organs, and with the other touched 

 the tail, I felt a shock; but much weaker than when touching it in the 

 usual manner; that is, with one hand on the upper surface of those organs, 

 and the other on the lower. If I laid a thumb on either surface of an 

 electric organ, and a finger of the same hand on any part of the body, 

 except on or very near the same surface of the organs, I felt a small shock. 



In all the foregoing experiments, the battery was charged to the same 

 degree, except where the contrary is expressed: they all seem to agree 

 very well with Mr Walsh's experiments. 



421] Mr Walsh found, that if he inclosed a torpedo in a flat basket, 

 open at the top, and immersed it in water to the depth of three inches, 

 and while the animal was in that situation, touched its upper surface with 

 an iron bolt held in one hand, while the other hand was dipped into the 

 water at some distance, he felt a shock in both of them. I accordingly 

 tried the same experiment with the artificial torpedo ; and if the battery 

 was charged about six times as high as usual, received a small shock in 

 each hand*. No sensible difference could be perceived in the strength, 

 whether the torpedo was inclosed in the basket or not. The trough in 

 which this experiment was tried was 36 inches long, 14^ broad, and 

 1 6 deep ; and the distance of that hand which was immersed in the water 

 from the electric organs of the torpedo, was about 14 inches. As it was 

 found necessary to charge the battery so much higher than usual, in order 

 to receive a shock, it follows, that unless the fish with which Mr Walsh 

 tried this experiment were remarkably vigorous, there is still too great a 

 disproportion between the strength of the shock of the artificial torpedo 

 when received under water and out of it. If this is the case, the fault 

 might evidently be remedied by making it of some substance which con- 

 ducts electricity better than leather. 



422] When the torpedo happens to be left on shore by the retreat of 

 the tide, it loosens the sands by flapping its fins, till its whole body, except 

 the spiracles, is buried; and it is said to happen sometimes, that a person 

 accidentally treading on it in that situation, with naked feet, is thrown 

 down by it. I therefore filled a box, 32 inches long and 22 broad, with 



* As well as I could judge, the battery required to be charged about 1 6 or 20 

 times as high, to give a shock of the same strength when received this way as when 

 received in the usual manner with the torpedo out of water. [Art. 615.] 



