176 LOCALIZED ELECTRIZATION. 



Before arriving at conclusions, from experiments upon animals, 

 with regard to the therapeutic action of continuous currents when 

 applied to human patients, it seemed to me more rational to 

 inquire whether the electro-physiological phenomena, observed in 

 vivisections, would be produced in a healthy man. But how 

 could a current be directed ujion a nerve, without first laying it 

 bare? Assuredly no one would venture to attempt such an opera- 

 tion in the human subject, for the purpose only of promoting 

 scientific research. And electro-puncture, in which the needle 

 traverses organs of different nature, and, as I have already shown, 

 produces complex phenomena, would not serve to display the 

 action of continuous currents upon nerve-trunks. 



It is now perfectly demonstrated, after my researches, that, 

 without puncturing or incising the skin, w^e may limit the electric 

 action at pleasure, either in the skin or in subcutaneous organs ; 

 and that by certain methods of proceeding, the electric excitation 

 will reach a nerve, without acting upon the skin that it penetrates. 

 Certain, from this, that I could limit the electrical action to the 

 chief nerve-trunks, I have studied, in a large number of sub- 

 jects, the influence of continuous currents upon contractility and 

 upon sensibility. I have principally selected for my experiments 

 the median nerve, the crural, and tlie internal and external pop- 

 liteal. Sometimes the rheophores have been placed on the course 

 of a nerve at a point where it is subcutaneous, and two or three 

 centimetres apart ; and sometimes they have been separated as 

 widely as possible, by placing, for example, one upon the brachial 

 plexus, or upon the sacral plexus at the posterior wall of the 

 rectum, and the other on the course of the nerve. The rheophores 

 have been placed in such a manner as to be only in relation with 

 the surface of the nerves. 



It has been shown, by numerous experiments upon animals, that 

 the continuous current manifests its special influence upon con- 

 tractility or upon sensibility, according to the direction in which 

 it passes longitudinally within the nerve, when the excitability has 

 been previously diminished by the more or less prolonged action 

 of a continuous current. 



To discover the influence of a continuous current upon a healthy 

 man, it was therefore necessary that the excitability of his nerves 

 should be first modified by the continuous current. For this 

 purpose, I employed, in the first instance, a trough battery (of 

 Cruikshank and Wollaston) composed of sixty couples, and I 

 caused a continuous current to pass through the nerves for from 

 tw^enty to thirty minutes, by placing them in the circuit of this 

 battery, and by using the method of procedure indicated above. 



