VOL. LXV.] PHILOSOPHICAL TRANSACXIONS,;^^ 57/ 



did not seem to make any alteration in the powers of the torpedo. Applying a 

 brass chain to the back of the fish, where I had put my thumb before, I found 

 no sensation at all in my hand, though I repeated the experiment often, and ap- 

 plied the chain for a space of time in which I always perceived a stroke.* This 

 was probably owing to the weakness of the fish in winter ; or perhaps because I 

 neglected to put my finger to its opposite side. Having insulated myself on an 

 electrical stand, and keeping the torpedo in my hand, in the manner abovemen- 

 tioned, I gave not the least sign of being electrified, whether I received a stroke 

 from the fish or not. The torpedo being suspended by a clean and dry silk rib- 

 band, it attracted no light bodies, such as pith-balls, or others, put near it. A 

 coated bottle applied to the fish, thus suspended, did not at all become charged. 

 When the fish gave the shock in the dark, I heard no crackling noise, nor per- 

 ceived any spark. When pinched with my nails, it did not give more or fewer 

 strokes than when not pinched. But by folding his body, or bending his right 

 side to his left side, I felt more frequent shocks. Dr. Drummond made these 

 experiments with me. 



We dissected some of the torpedos, and found, if I remember well, 4 very 

 large bundles of nerves, passing sidewards from the head into the 1 soft bodies, 

 called musculi falcati, and distributed by dense ramifications through their whole 

 substance. These nerves seem to terminate in round threads, which surround 

 certain cylinders of a transparent gelatinous substance, which seems to consti- 

 tute the material part of these singular bodies that appear to be the reservoirs of 

 the electric power : these cylinders are parallel to each other, and have their 

 direction from the under to the upper side of the fish. I did not observe whether 

 these soft bodies changed in size when the torpedo gives a shock, but I suspect 

 they do. 



//. Of Two Giants Canseivays, or Groups of Prismatic Basaltine Columns, and 

 other curious Fitlcanic Concretions, in the Venetian Slate in Italy ; with some 

 Remarks on the Characters of these and other Similar Bodies, and on the Phy- 

 sical Geography of the Countries in which they are found. By John Strange, 

 Esq. F.R.S. p. 5. 



Mr. S. first gives a topographical view of a part of the south-east side of a 

 hill, called Monte Rosso, about 7 miles nearly south of Padua, in the Venetian 

 State in Italy, and a mile to the west of Abano, a village well known, from the 

 celebrated hot baths of that name, and which are situated at half a mile distance 



* Dr. Ingenhousz means, that he felt no shock, though he saw the animal, by the contortion of 

 its body, give one to the chain. At that time he did not seem to know, that though the shock 

 would be communicated by a rod of any metal, it could not be so by a chain, or where there was 

 the least interruption of continuity. — Orig. 



VOL. xm. 4E 



