FISHES. 509 



Hcquired them the name of the torpedo. These are described by 

 Atkins and Moore, and found in great abundance along the coast 

 of Africa. They are shaped like a mackarel, except that tlie 

 liead is much larger ; the effects of these seem also to differ in 

 some respects. Moore talks of keeping his hand upon the 

 animal ; which in the ray torpedo it is actually impossible to do. 

 " There was no man in the company," says he, " that could bear 

 to keep his hand on this animal the twentieth part of a minute, 

 it gave him so great pain ; but upon taking the hand away, the 

 numbness went off, and all was well again. This numbing 

 quality continued in this torpedo even after it was dead ; and the 

 veiy skin was still possessed of its extraordinary power till it 

 T)ecame dry." Condamine informs us of a fibh possessed of the 

 powers of the torpedo, of a shape very different from the former, 

 and every way resembling a lamprey. This animal, if touched 

 by the band, or even with a stick, instantly benumbs the hand 

 and arm to the very shoulder ; and sometimes the man falls down 

 under the blow. These animals, therefore, must affect the 

 nervous system in a different manner from the former, both with 

 respect to the manner and the intention ; but how this effect is 

 wrought, we must be content to dismiss in obscurity.' 



1 From a number of experiments made by Mr Walsh, and communirated 

 to the Royal Society, it appears that the powers of this animal are purely 

 electric ; though no spark could ever be discovered to proceed from it, nor 

 WQve pith-balls ever affected by it. "A live Torpedo," says he, "was 

 placed on a table; round another table stood five persons insulated; two 

 brass wires, ea<-h thirteen feet htng, were suspended from the ceiliiif^ by 

 silken strings ; one of these wires rested by one end on the wet napkin on 

 which the fish lay ; the other end was immersed in a basin full of water, 

 placed on a second table, on which stood four other basins likewise full of 

 water ; the first person put a fin^'er of one hand in the basin in which the 

 wire was imraeised, and a fini,'er of the other hand in a second basin, the 

 second person put a fiuffer of one hand in this last basin, and a fiufjer of the 

 other hi.nd in the third; and so on successively, till the five persons com. 

 municated with one another by the water in the basins. In the last basin, 

 one end of thesecimd wire was immersed, and with the other end Mr Walsh 

 touched the torpedo ; when five persons felt a commotion, which differed in 

 nothing from that of the Leyden experiment, except in tlio deg-ree of force. 

 Mr Walsh, who was not in the circle of conduction, received no shock. 

 The action of the torpedo is communicated by the same mediums as that of 

 the electric fluid; and the bodies which intercept the action of the one, in. 

 tercept likewise the action of the other. The effect produced by the tor. 

 pedo, when in air, appeared, on many repeated experiments, to be .iboiit 

 four times as string as. when in water. '1 ho nuitibness produced by the 



