R A I A. 



313 



contained between every two of the latter. In the 

 torpedo these extend all the way from the integu- 

 ments of the upper surface to those of the under, their 

 ends being fastened to those surfaces, and their axes 

 perpendicular to the plane of the fish. 



It is unnecessary, however, to go ino any minute 

 description of these with a view of ascertaining in 

 what manner the energies are connected with the 

 structure. No doubt they are connected with that 

 structure ; and the different 'tubes or columns, with 

 their partitions, and their intermediate fluid, have 

 some slight resemblance to the common galvanic 

 trough. But here the parallel stops, and a new ele- 

 ment comes in, which forbids all farther comparison. 

 The action of these organs depends upon the life of 

 the animal, being vigorous or feeble, according as 

 that is more or less ; and while the electrical fishe< 

 benumb the senses of whatever living creature they 

 strike, they become greatly exhausted by the effort, 

 and soon lose their power, until they have rested and 

 recovered themselves ; and when Hie is extinct, the 

 power of giving shocks is at an end, and cannot be 

 revived in the dead body. 



This species of electric, galvanic, or whatever other 

 action it may be called, is therefore a phenomenon of 

 life, modified by organisation, and not belonging to, 

 or producible in, dead matter. It tend?, however, to 

 show that there is a close connection between the 

 electricity or galvanism of matter and this power of 

 these fishes, though in the fishes it belongs to the life 

 acting by means of organs, and in the other cases it 

 belongs to matter, as such, without any reference to 

 life or organisation. In this it follows the general 

 law of the animal economy : it is a universal property 

 of living creatures to assimilate substantive matter, 

 and turn it into the substance of their own bodies ; 

 and the very same law demands that in every case, 

 according as it may be necessary to the part which 

 the animal has to perform in the grand system of 

 nature, it should have the power of assimilating 

 action, and modifying that by its organisation, so as 

 to accomplish those purposes for which it is appointed. 

 But when those modifications, either of substantive 

 matter or of action by a living creature, are intro- 

 duced,^they completely destroy the analogy between 

 the action of animals and the action of inanimate 

 matter ; so that, if we attempt to reason from a com- 

 parison from the whole of the one case to the whole 

 of the other, we are sure to fall into error ; and if we 

 say one word beyond this we destroy the simpler 

 and more useful part of the comparison, which is 

 realb/ matter of philosophy. 



There is another circumstance connected with these 

 electric fishes which is worthy of attention, as tend- 

 ing to establish the distinction which we have endea- 

 voured to point out. If the expression ma}' be used, 

 the electric action of matter, in what manner soever 

 it is exerted, appears to act on the matter of the 

 body as obeying the life, rather than on the life itself; 

 whereas the animal electricity appears to act directly 

 on the living principle, and only through that upon 

 the material part of the body. 



This may seem a nice distinction, and one which 

 is much too subtile for popular description. Such, 

 however, is not the case ; because those nice points 

 of physiological distinction have a far more extensive 

 range than the mere natural history even of animals ; 

 and it is in the misapprehension of them that the 

 foundations of our most serious errors are laid. Ob- 



NAT. HIST. VOL. III. 



servation shows that the muscles, as organs of motion 

 in obedience to the animal life, but not that life itself, 

 or capable of acting without, are affected by ordinary 

 electricity and galvanism ; and in proof that they are 

 so^hffected simply as matter, and not as living matter 

 or life, is established by the fact, that they can excite 

 the muscles after life is extinct, and until decompo- 

 sition has made certain advances. The shock given 

 by the electric animal does also affect the muscles ; 

 but this is not its ultimate or its most powerful effect. 

 Its tendency is to stupit'y the senses, and take down 

 not the tone of the mere muscular system, but the 

 energy of the life which puts that system in motion. 



We have felt it necessary to make these remarks 

 at some length, in consequence of a remark by Mr. 

 Couch contained in a quotation which we shall pre- 

 sently make from Mr. Yarrell's excellent " History 

 of British Fishes," to which we have so often to refer, 

 and always with pleasure. Mr. Couch deserves the 

 greatest praise for the zeal, assiduity, discrimination, 

 and success of his observations. But Mr. Couch 

 must look to his philosophy even with keener eyes 

 than if he were an inferior man ; because in him the 

 sterling metal so preponderates, that it is almost sure 

 to carry whatever of alloy may accompany it into 

 general circulation. The passage is as follows, the 

 quotation within single commas : " The whole use 

 of the electrical apparatus and power to the fish can 

 only be conjectured. That it serves as a means of 

 defence is very probable. Mr. Couch thinks other 

 powers may be derived from it, and his opinion is 

 thus expressed : ' One well-known effect of the elec- 

 tric shock is to deprive animals killed by it of their 

 organic irritability, and consequently to render them 

 more readily disposed to pass into a state of decom- 

 position, in which condition the digestive powers more 

 speedily and effectually act upon them. If any 

 creature more than others might seem to require such 

 a preparation of food, it is the cramp-ray, the whole 

 canal of whose intestine is not more than half as long 

 as the stomach. 



" ' So long ago as the time of Dioscorides, the phy- 

 sician of Antony and Cleopatra, the shock-of this fish 

 was recommended for medical purposes, and especially 

 for pains in the head ; and this may be considered as 

 the curliest record of the application of electricity to 

 medicine. In later times it was applied to the cure 

 of trout, the patient being directed to keep his foot 

 on the fish until the numbness extended to the knee. 

 Baron Humboldt (speaking of the Gymiiotus, we pre- 

 sume) remarks, that the will of the fish directs the 

 effect to whatever part it feels most strongly irritated, 

 but only under the influence of the brain and heart. 

 When a fish was cut through the middle, the fore 

 part of the body alone gave shocks.'" 



Mr. Yarrell makes no remark on any portion of 

 this passage which we have quoted ; though it ap- 

 pears that his own conjecture of the electricity being 

 a means of defence is far more probable than the 

 conjecture of Mr. Couch. The tail of the torpedo 

 is without spines, or any of those weapons with which 

 the tails of the true rays are furnished, and which 

 weapons they use with no inconsiderable effect, lash- 

 ing about with the tail, somewhat as a man would 

 defend himself with a threshing flail, or with the 

 morgensteirn of the ancient Saxon?. The tail of the 

 torpedo is quite unfit for this, both from its stiffness 

 and its want of armature ; and thus, were it not for 

 its power of giving shocks, it would be one of the 

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