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Dr. C. B. Radcliffe on Animal Electricity. [June 16, 



the charge be negative or positive, the results are the same, and therefore it is 

 plain that there ought also to be increased contraction in anelectrotonus if 

 this be the true explanation of the increased contraction which happens in 

 cathelectrotonus. In cathelectrotonus it is assumed that the negative charge 

 from the negative voltaic pole charges the outsides of the sheaths of the fibres 

 negatively, and induces an equivalent charge of positive electricity on the in- 

 sides ; in anelectrotonus, on the other hand, it is assumed that the positive 

 charge from the positive voltaic pole brings about a contrary state of things 

 in the fibres, charging the outsides of the sheaths positively, and affecting the 

 insides negatively by induction. The difference assumed to exist between 

 the two electrotonic states is in the relative position of the two charges 

 upon the sheaths of the fibres, nothing else. It is not a difference which 

 can affect the elongation of the fibre if elongation be brought about by the 

 mutual attraction of the opposite charges with which the sheaths are 

 charged ; for the attraction of either charge for the other must be the same, 

 whether it be exercised from within the sheath or from without it. It 

 follows, indeed, from what is supposed, not only that there should be in- 

 creased contraction in anelectrotonus as well as in cathelectrotonus, but 

 also that the state of rest in both electrotonic conditions should be 

 characterized by increased elongation. And what there should be in 

 theory there is in fact ; for it proves on inquiry that contraction may be 

 caused in anelectrotonus by an adequate " stimulus," that this contraction 

 is greater than that caused by the same " stimulus " in the unelectrotonized 

 state, and that actual increased elongation of the fibres is an effect of both 

 cathelectrotonus and anelectrotonus. The view of muscular action here 

 taken is that which has been always advocated by the author as regards 

 contraction, but it is modified somewhat as regards elongation; for now, 

 instead of looking upon elongation as arising from the mutual repulsion 

 among the muscular molecules set up by the presence in the muscle of a 

 single charge of electricity, this state is referred to the mutual attraction of 

 opposite electrical charges disposed, as in a Leyden jar, upon the two sur- 

 faces of the sheaths of the muscular fibres. 



Looking back, then, at the history of electrotonus there appears to be 

 nothing contradictory to what has been already said respecting the work- 

 ings of electricity upon nerve and muscle. It is still the same story of 

 rest along with the state of charge, and of action along with the state of 

 discharge, with this significant addition, that in electrotonus the charge is 

 shown, not only as coincident with the state of rest, but as having an 

 actual power of suspending action in both nerve and muscle, and of causing 

 increased elongation of the fibres in muscle. 



