Torpedo, Gymnotus eleSlricus and Silurus ele&r'icus. 135 



cefs, had approached nearly to the theory of eleftriclty ; it is 

 at leafl; probable that they referred to the lame caufe the 

 fulminating effeds of the torpedo, and thofe, much more ter- 

 rible, of celeftial eleiSlricity. We can form no opinion of 

 their knowledge in natural hi (lory but by the names which 

 they have given to mod of the productions of nature. Thefe 

 names have been preferved without alteration ; for it is only 

 to the sera when the fciences flouriftied in the Eaft that we 

 mufl: refer the rational nomenclature ftill employed by the 

 rude inhabitants of Egypt. Every animal in that coun- 

 try, as well as in books of natural hiftory, has two names, 

 that of the genus and that of the fpecies. There is no ex- 

 ception but in favour of the torpedo and the filurus eleftri- 

 cus. Every thing which related to the form of thefe fiihes 

 has been neglefted, and notliing has been attended to but 

 their aftonifliing faculty of flriking with torpor all the fmall 

 marine and freOi water fiflies. Though very different, they 

 have been diltinguillied by the fame name; and, what is very 

 remarkable, this name, rdad or raafch, is that ufed to cxprels 

 thunder. In giving this denomination to the torpedo and 

 the filurus eleStricus, did the Arabs think of referring ihe 

 phsenomena of animal eleftricity to celeftial eleftricity? 



Explanation of the Figures, Plate III. 



Fig. I. the torpedo {Raid torpedo). 



a, eleftric organ compofcd of tubes. 



b, the upper (kin turned back on the fide to fliow the elec- 

 tric organ. 



Fig. 2. the red ray {Raia rubus). 



a, a, aponeurotic tubes which communicate on the outfide 

 of the fkin by peculiar orifices. 



b, the fkin of the flanks turned back on the fide. 

 71, nerve of the fifth pair. 



i, focus in which the nerve of the fifth pair expands, and 

 from which proceed, in a radiated form, in ieveral bundles, 

 the tubes which open on the outfide of the fkin. 



Fig. 3. tranfvcrfe fcAion of the eleftric eel, gjmnotus elcc- 

 tricus. 



g,g, large eleftric organs. 



p,p, fmall electric organs. 



•y, air-bladder. 



7ii,m,m,?n, longitudinal mufcles. 



0, vertebral colunyi. 



d, fkin feen on the outfide. 



c, anal fin. 



K 4 Fig. 4. 



