Electro-physiology and electro-therapeutics : showing the best methods for the medical uses of electricity / By Alfred C. Garratt.

Electro-magnetic currents, as they have been more generally called, are usually obtained from a helix machine, in connection with a single galvanic pair, (which latter is of itself a battery;) but, taken together, this is known in our country as the Electro- magnetic Machine. The kind of electricity thus obtained could Fig. 17. Electromagnetic Helix and Battery, with a Rasp for breaking the Current by hand. be more strictly termed " galvano-magneto-electric currents of induction," because induced by both these sources combined, by the arrangement of one and the same apparatus. There are also other forms of induction currents that are called by other compound names. The author proposes, for the sake of con- ciseness and uniformity, to designate the peculiar kind of elec- tricity obtained by any and all sorts of induction apparatus, whether from battery or permanent steel magnets, in connection with medical purposes, as Faradaic electricity, Faradaic cur- rents, and so on. True, the initiatory steps that led on to this grand discovery had already been taken by Oersted, Ampere, Arago, and by Henry; yet to the illustrious English philosopher, Dr. Faraday, are we indebted most of all for this magnificent result. Besides, it is well known that Dr. Duchenne, of France, one of the most distinguished medical electricians of the age, has already designated, in his elaborate work, the " localization of induction currents to a single muscle" as '•'■Faradization.''' Let that kind of current, then, in this relation, and the medi- cal use of these currents, henceforth take his name. The term Faradaic electricity, wherever it may recur in this work, is simply synonymous with the terms " induction cur- rents," " electro-magnetism," or " magneto-electricity," and