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

the injured substances of the cerebrum; whilst spinal paralysis may arise from the injured substances of the spinal marrow, or from the injured substance or function of spinal nerves: any disease, in effect, which severs the influence of the spinal mar- row from the muscles. In this sense, for example, the paralysis arising from lead is spinal paralysis. " It is well known that in this disease the tone of the muscles and the irritability of the muscular fibre are diminished. I may here observe, that the hand and arm, contracted by tone from cerebral paralysis, are contracted symmetrically and with- out distortion, — all the muscles being equally affected, — the flexors overcome the extensors, the arm is bent, and the hand closes firmly but regularly. In spasmo-paralysis, on the con- trary, certain muscles only are excited to contraction ; and that contraction is irregular, clonic, and tonic, and the arm and hand are affected with various deformities, scarcely admitting of description, but which it woidd be highly interesting to depict." Dr. Hall, therefore, laid down the following propositions: — " If the hands of a healthy person be subjected to the action of electro-magnetic currents, they are energetically closed; the flexor muscles being more massive and powerful than the ex- tensors, the former are more forcibly contracted than the latter; it is their power, not their irritability, which is tested." But it is to an actual case in point that we must appeal; and I beg here to introduce an experiment, made to determine the question before us, viz., that of results obtained by the two kinds of electric current apparatus to which I have adverted. I give it in the words of Mr. Smith. This experiment was made on the 10th of November, 1847. " In a case of hemiplegia of three years and a quarter's dura- tion, in a man aged twenty-eight, the arm being slightly wasted and the hand contracted, the leg only a little enfeebled, we first applied the continuous primary current from the common Cruik- shank battery ; the two hands being placed in salt water in one basin, while the feet were in another; then, on using a small number of plates, the muscles of the paralyzed arm were found to be slightly affected by the current, but which did not in-