, 300 PROFESSOR MATTEUCCrs ELECTRO-PHYSIOLOGICAL RESEARCHES. 



removed as possible from the internal part. A pile so formed has given constant and 

 distinct signs of a current directed in the muscle from the tendon to the muscle. 

 With regard to the intensity, I must add that the signs have always been weaker, 

 from the pile composed of recti femoris, than those from the pile of half legs or gas- 

 trocnemii muscles. 



It is very natural that the cause of this difference should be owing to the fact of 

 the muscular current circulating in a contrary direction to the other. And, in truth, 

 if the disposition of the elements which compose these piles be ever so little changed, 

 so that the tendon of one of these elements be made to repose upon or near to the 

 interior of the muscle, the signs of every current become very weak or cease alto- 

 gether (fig. 10.). 



I have prepared a number of anterior cubital muscles, or muscles of the fore-arm 

 of frogs, which likewise have at their extremities, near the carpus, a very distinct 

 tendinous band, A pile composed of these muscles, disposing them as usual, with the 

 tendon resting on the muscular surface of the next element, gives constant and very 

 distinct signs of a current, the direction of which, in the muscle, is from the tendon 

 to the muscle. The following in the meanwhile is the generalization of the fact of 

 the proper current of the frog : the current is directed within the muscle from the 

 tendon to the superficies. 



It remained for me to extend this fact to its operation upon the muscles of warm- 

 blooded animals, and the experiments accorded in such a manner as to leave no 

 possible doubt. 



In these experiments I employed fowls, pigeons, rabbits and dogs. It is necessary 

 to operate with great rapidity upon these animals, since, as in the muscular current, 

 the signs of the current which we are now studying cease very quickly. Not less 

 than six or eight elements are necessary for eliciting signs of this current sufficiently 

 evident to remove all doubt. In all these animals the muscular extremities turned 

 towards the feet are furnished with tendons much more distinct and grouped toge- 

 ther than those of the upper and opposite extremities. I wished at first to have 

 separated the different muscles as I had done those of the frogs, but the process is 

 much more difficult with the muscles of these animals, which always get considerably 

 lacerated. 



In order to succeed in the best possible manner, after having removed the integu- 

 ments, I cut the thigh as near as possible to the articulation with the os ilium ; and 

 in pigeons it is easy to tear the thigh out of the socket. The surface of these ele- 

 ments should be well-dried and the pile formed (fig. 11.), disposing them in such a 

 manner that the inferior extremity of the leg, where the tendons unite together, re- 

 poses upon the surface of the muscular masses of the leg. In this manner the muscles 

 of the thigh have no part in the circuit. From similar dispositions of eight elements 

 taken from rabbits or pigeons, the signs of a current, marked by my galvanometer, 

 were from 12° to 15°, and 20°, and directed in the pile from the tendinous extremities 



