VOL. LXVI.j PHILOSOPHICAL TRANSACTIONS. 31 



One of the fishermen employed by Mr. Walsh assured him, that he always 

 knew when he had a torpedo in his net, by the shocks he received while the fish 

 was at several feet distance ; in particular, he said, that in drawing his nets with 

 one of the largest in them, he received a shock when the fish was at 12 feet dis- 

 tance, and 2 or 3 more before he got it into his boat. His boat was afloat in 

 the water, and he drew in the nets with both hands. It is likely that the 

 fisherman might magnify the distance ; but probably he may so far be believed, 

 as that he felt the shock before the torpedo was drawn out of water. This is 

 the most extraordinary instance 1 know of the power of the torpedo ; but I 

 think seems not incompatible with the supposition of its being owing to elec- 

 tricity ; for there can be little doubt, but that some electricity would pass through 

 the net to the man's hands, and thence through his body and the bottom of the 

 boat, which in all probability was thoroughly soaked with water and perhaps 

 leaky, to the water under the boat : the quantity of electric fluid however, 

 taking this circuit, would most likely bear so small a proportion to the whole, 

 that this effect can not be accounted for, without supposing the fish to exert at 

 that time a surprizingly greater force than what it usually does. 



Hitherto the effects of this artificial torpedo appear to agree very well with 

 those of the natural one. I now proceed to consider the circumstance of the 

 shock's not being able to pass through any sensible space of air. In all my ex- 

 periments on this head, I used the first torpedo, or that made of wood ; for as 

 it is not necessary to charge the battery more than one-third part as high to give 

 the same shock with this as with the other, the experiments were more likely to 

 succeed, and the conclusions to be drawn from them would be scarcely less con- 

 vincing : for I find, that 5 or 6 rows of my battery will give as great a shock 

 with the leathern torpedo, as one row electrified to the same degree will with the 

 wooden one : consequently, if with the wooden torpedo and my whole battery, 

 I can give a shock of a sufficient strength, which yet will not pass through a 

 chain of a given number of links, there can be no doubt, but that if my battery 

 was 5 or 6 times as large, I should be able to do the same thing with the leathern 

 torpedo. 



I covered a piece of sealing wax on one side with a slip of tin foil, and hold- 

 ing it in one hand, touched an electrical organ of the torpedo with the end of it, 

 while my other hand was applied to the opposite surface of the same organ. 

 The shock passed freely, being conducted by the tin foil ; but if I made, with a 

 penknife, as small a separation in the tin foil as possible, so as to be sure that it 

 was actually separated, the shock would not pass ; conformably to what Mr. 

 Walsh observed of the torpedo. I tried the experiment in the same manner 

 with the Lane's electrometer described before, and found that the shock would 



