Artificial electric torpedo 199 



by means of the following apparatus. ABCFGDE, Fig. 3, is a piece of 

 wood, the part ABCDE of which is cut into the shape of the torpedo, 

 and is i6f inches long from A to D, and lof broad from B to E; the part 

 CFGD is 40 inches long, and serves by way of handle. MNmn is a glass 

 tube let into a groove cut in the wood. Ww is a piece of wire passing 

 through the glass tube, and soldered at W to a thin piece of pewter Rr 



\ 



Fig- 3- 



lying flat on the wood, and intended to represent the upper surface of the 

 electric organs. On the other side of the wood there is placed such another 

 glass tube, not represented in the figure, with a wire passing through it, 

 and soldered to another piece of pewter of the same size and shape as Rr, 

 intended to represent the lower surface of those organs. The whole part 

 A BCDE is covered with a piece of sheep's skin leather. 



410] In making experiments with this instrument, or artificial torpedo 

 as I shall call it, after having kept it in water of about the same saltness 

 as that of the sea, till thoroughly soaked, I fastened the end of one of the 

 wires, that not represented in the drawing for example, to the negative 

 side of a large battery, and when it was sufficiently charged, touched the 

 positive side with the end of the wire Ww; by which means the battery 

 was discharged through the torpedo: for as the wires were inclosed in 



Fig. 4 . 



glass tubes, which extended about an inch beyond the end of the wood FG, 

 no electricity could pass from the positive side of the battery to the nega- 

 tive, except by flowing along the wire Ww to the pewter Rr, and thence 

 either through the substance of the wood, or along the wet leather, to the 

 opposite piece of pewter, and thence along the other wire to the negative 

 side. When I would receive a shock myself, I employed an assistant to 

 charge the battery, and when my hands were in the proper position, 



