VOL. LXVI.] PHILOSOPHICAL TRANSACTIONS. 33 



tate the effects of the real one, though it approaches near to it ; for the shock of 

 the former, when not stronger than that of the latter frequently is, will pass 

 through 4 or 5 intervals of the links of a chain ; whereas the real torpedo was 

 never known to force his through a single interval. But I think this by no 

 means shows that the phenomena of the torpedo are not produced by electricity; 

 but only that the battery I used is not large enough. For we may safely con- 

 clude, from the experiments mentioned before, that the greater the battery is, 

 the less space of air, or the fewer links of a chain, will a shock of a given 

 strength pass across. For greater certainty however, I tried whether, if the 

 whole battery and a single row of it were successively charged to such a degree, 

 that the shock of each should be of the same strength when received through 

 the torpedo in the usual manner, that of the whole battery would be unable to 

 pass through so many links of a chain as that of a single row. From which it 

 appears, tliat if the whole battery, and a single row of it, are both charged in 

 such a degree as to give a shock of the same strength, the shock with the whole 

 battery will pass through fewer loops of the chain than that with the single row; 

 so that I think there can be no doubt, but that if the battery had been large 

 enough, I should have been able to give a shock of the usual strength, which 

 yet would not have passed through a single interval of the links of a chain. 



On the whole, there seems nothing in the phenomena of the torpedo at all 

 incompatible with electricity ; but to make a complete imitation of them, would 

 require a battery much larger than mine. It may be asked, where can such a 

 battery be placed within the torpedo ? I answer, perhaps it is not necessary that 

 there should be any thing analogous to a battery within it. The case is this ; it 

 appears that the quantity of electric fluid, transferred from one side of the tor- 

 pedo to the other, must be extremely great ; for otherwise it could not give a 

 shock, considering that the force with which it is impelled is so small as not to 

 make it pass through any sensible space of air. Now if such a quantity of fluid 

 was to be transferred at once from one side to the other, the force with which it 

 would endeavour to escape would be extremely great, and sufficient to make it 

 dart through the air to a great distance, unless there was something within it 

 analogous to a very large battery. But if we suppose that the fluid is gradually 

 transferred through the electrical organs, from one side to the other, at the 

 same time that it is returning back over the surface, and through the substance, 

 of the rest of the body ; so that the quantity of fluid on either side is, during 

 the whole time, very little greater or less than what is naturally contained in it ; 

 then it is possible, that a very great quantity of fluid may be transferred from 

 one side to the other, and yet the force with which it is impelled be not sufficient 

 to force it through a single interval of the links of a chain. There seems how- 

 ever to be room in the fish for a battery of a sufficient size ; for Mr. Hunter 



VOL. XIV. F 



