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

says Remak, then a direct excitement of the antagonistic nerve trunk ought to produce contractions only in the reach of its own ramifications; and the same should happen also when the ex- citement includes hoth nerve trunks simultaneously. But in apparent contradiction is the following : — Where a current, when traversing the nerve medianus, pro- duces extension, i. e., a contraction of the extensor muscles, so as to open the hand, yet we find, as soon as the nerve radialis alone of that arm is placed in the current, or where the media- nus and the radialis are connected, as hy a wet bandage, so as to be imder the same electrode which is placed on the upper arm, there is then contraction of the flexors. The same work- ing and effect are produced when the end of the wet strip is carried from any point on the nerve medianus that is included in the circuit, to any point or part of the extensor side of the arm or forearm, below where the nerve radialis runs out to its ulti- mate ramifications. This same effect is sometimes produced when a wet strip is carried from the nerve medianus to the back of the hand or fingers. This simultaneous excitement of the nerves running out on the back surface of the arm and hand, when continued a minute or so, produces not merely a tempo- rary, but also a lasting, influence on the tonic contractions. For if now the wet pad is removed, and the arm is perfectly dried, and the current is so directed as to course through the nerve medianus alone, we find we do not now get extension, as before, but tonic flexion ; and it continues to act thus until, by repeated special voluntary motions, its extensors have regained their capa- bility to respond to the excitement in the usual manner. It is quite necessary sometimes, after this trial, to rub the fingers and muscles briskly, to bring them back to their normal sensibility and capability. 13. However difficult it might be to find a common law for these paradoxical phenomena, it was highly probable that they could arise from some disturbance in the equilibrium of the central organs, as tonic innervation ; or, perhaps, the excitement ■of the sentient nerves play a real part in the result. This latter suspicion was all the more confirmed by this, viz.: that,