804 



ANNUAL REGISTER, 1804 



pass along with the nerrcs to the 

 electric organ, and enter with them ; 

 tken ramify, in every direction, into 

 innumerable small branches upon the 

 sides of the columns, sending in from 

 the circumference all around, upon 

 each partition, small arteries, which 

 ramify and anastomose upon it ; 

 and, passing also from one partition 

 to another, anastomose with the ves- 

 sels of the adjacent partitions. The 

 Teins of the electric organ pass out 

 close to the nerves, and run between 

 the giUs-to the auricle of the heart, 

 The nerves inserted into each elec- 

 tric organ, arise by three very large 

 trunks from the lateral and posterior 

 part of the brain. The first of these, 

 in its passage outwards, turns round 

 a cartilage of the cranium, and sends 

 a few branches to the first gill, and 

 to the anterior part of the head, and 

 then passes into the organ near its 

 anterior extremity. The second 

 trunk enters the gills between the 

 first and second openings, and, after 

 furnishing it with small branches, 

 passes into the organ near its middle. 

 The third trunk, after leaving the 

 skull, divides itselfinto two branches, 

 which pass to the electric organ 

 through the gills ; one between the 

 second and third openings, the other 

 between the third and fourth, giving 

 small branches to the gill itself. — 

 These nerves, having entered the 

 organs, ramify in every direction 

 l)etvveen the columns, and send in 

 small branches upon each partition, 

 where they arc lost, 'i'he magnitude 

 and number of the nerves bestowed 

 on these organs, in proportion to 

 their size, must, on reflection, ap- 

 pear as extraordinary as the phaeno- 

 mena they alford. Nerves are given 

 to parts either for sensation or ac- 

 tion. If we except the more impor- 

 tant senses of hearing^ scoing, tast- 



ing, and smelling, which do not he* 

 long to electric organs, there is no 

 part, even of the most perfect ani- 

 mals, which, in proportion to its 

 size, is so liberally supplied with 

 nerves; nor do the nerves seem ne- 

 cessary for any sensation Mhich can 

 be supposed to belong to the electric 

 organs ; and, with respect to action, 

 there is no part of any animal with 

 which I am acquainted, however 

 strong and constant its natural ac- 

 tions may be, which has so great a 

 proportion of nerves. If it be then 

 probable that those nerves are not 

 necessary for the purposes of sensa- 

 tion or action, may avc not conclud« 

 that they are subservient to the for- 

 mation, collection, or management 

 of the electric fluid ? especially as it 

 seems evident, from Mr. Walsh's 

 experiments, that the will of the ani- 

 mal does absolutely <;ontrol the elec- 

 trie powers of its body, which must 

 depend on the energy of the nerves." 



From the above description, it 

 appears that the electric organs of 

 the torpedo constitute a pair of 

 Galvanic batteries, disposed in th« 

 form of perpendicular hexagonal 

 columns. In the Gymnotus electri- 

 cus, on thc<;ontrary, the Galvanic 

 battfry is disposed lengthways on 

 the lower part of the animal. 



We are informed by the ingenious 

 Dr. Ingenhouz, that, on taking up 

 some torpedos, about twenty miles 

 from Leghorn, and on pressing 

 gently with the thumbs on the upper 

 side of the two soft bodies on each 

 side of the head, (the electric or- 

 gans) in about the space of a minute 

 or two, he felt a sudden trembling 

 in the thumbs, which extended no 

 farther than the hands, and lasted 

 about two seconds, perfectly resem- 

 bling the sensation produced by a 

 great number of very small electrical 



bottles, 



