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

current for remedial purposes. The up-running current he thinks best suited to allay tetanus and convulsions, if the en- trance convulsion is only avoided. He mostly agrees with Nobili on the action of Volta's alternatives, as for instance where a nerve has been deprived of its excitability by a given prolonged current direction, it is re-acquired simply by the reversion of the direction of the current; and furthermore, as Marianini discovered, so Matteucci verifies, that the up-running current excites mostly the motor)) nerves, the down-running current excites mostly the sentient nerves; but presupposing always that the disease or derangement of the nerves is akin to that condition which can be produced by a strong, even, and long continued current in the same direction. We now approach another epoch in the history of electro- physiology and electro-therapeutics: I refer to the researches of M. Dubois-Rcymond. It appears to have been the main object of this great man to test and put to rest the truth as to the nature of the powers active in the nerves and muscles of liv- ing men. To demonstrate, — the identity, or degree of iden- tity, there is between the electro-motive force, artificially pro- duced, and the functional force of the living human organism, and to ascertain the workings of electric currents through the nerves and muscles as nature's method or means to put the original powers of these textures into action, — we shall have to recur frequently to the general theory of nerve and muscle excite- ment developed in his hands, from the very careful and conscien- tious trials he so perseveringly instituted. The electro-tonic state, or " electrotonus," so nicely examined by him, arrests our first attention. After Dubois-Reymond had ascertained that not merely the muscles, but also the nerves, of a recently amputated limb show a mi generis electrical current, called the quiet nerve current, and always flowing from the lon- gitudinal to the transverse cut of muscles, he observed,— 1. That this native current increases in strength as long as a constant current is made to flow along on the edge or side part of the nerve region that is being tested, provided the artificial current, that is so applied, runs in the same direction with the natural nerve and muscle current.