LARGE DOUBLE-CURRENT VOLTA-FARADIC APPARATUS. 243 



perfection. The number of induction instruments produced, and 

 variously improved or modified, has so increased, both in France 

 and in other countries, that to describe them would require me to 

 enter into details which would carry me far beyond the limits I 

 have set to my task. The laudable efforts referred to have pro- 

 duced some highly ingenious forms of apparatus. Unfortunately, 

 the inventors have chiefly sought to diminish size and price, and 

 have not always been sufficiently impressed with the importance 

 of the most recent requirements of science and of therapeutics ; 

 requirements arising from the method of localized faradization, 

 and from the discovery of the several properties of the currents of 

 the different coils. 



The critical observations that I made upon the instruments in 

 general, were founded upon long experience of those wliich then 

 were chiefly used. It seemed to me that the very severity of my 

 criticism imposed upon me a new duty, — that of endeavouring to 

 produce instruments that should be better. For this reason, I 

 devoted myself with ardour to a new order of researches, in little 

 harmony with my habits, and which would even have been very 

 irksome, if I had not possessed some aptitude and taste for 

 mechanics, and if I had not kej)t constantly before my mind the 

 realization of a single idea, — the localization of the electric force in 

 organs, and its application to medical science. 



1 therefore set myself to frequent workshops, in which I 

 acquired many of the secrets of manufacture ; and, after several 

 trials, I was able to produce instruments made by my own hands, 

 although I had previously never used a file or a hanuuer. From 

 these models I have drawn the designs for the volta-faradic and 

 magueto-faradic instruments which have been skilfully manu- 

 factured by MM. Charriere and Deleuil. Since then, they have 

 undergone new and important modifications, all of which will be 

 described in the next part of this chapter ; while, in a subsequent 

 part, I shall pass in review the instruments that are chiefly 

 employed, and subject them to critical examination. 



Part the Second. 



the author's large double-current volta-i^aradic 

 apparatus. 



My double-current volta-faradic apparatus was, in its original form, 

 somewhat complicated ; and it underwent the fate of every new 

 mechanical contrivance. The number of its connections rendered 

 a description difficult to understand, and, although the metliod of 

 setting it in action was very simple, occasioned frequent derange- 



R 2 



