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

junction of the two upper thirds of the humerus with its lower one third. The musculo-cutaneous nerve may be reached high in the axilla. On the thigh, we may reach the crural nerve in the groin, just outside the femoral artery; the two popliteal nerves, in the popliteal space under the knee. The sciatic nerve is accessible most perfectly (but most inconveniently) within the pelvis, i. e., through the posterior wall of the rectum; on the outside, also, just back of the great trochanter, and between that and the tuberosity of the ischium. This latter is the more usual spot chosen. The trunk of the facial (portio dura) nerve can be readied from the external opening of the car, or after the nerve emerges from the stylo-mastoid foramen just under the ear, by placing one electrode between the mastoid process and the condyloid process of the lower jaw. But he thinks neither of these ways should be resorted to in cases of paralysis of the portio dura, because from that point in the ear the feebler currents produce no effects on the muscles of the face ; while if we employ requi- site currents to produce an effect on the face muscles, the electric stimulus is then inevitably conveyed to the superficial temporal, or to the auriculo-temporal nerve from the third branch of the trigeminal (trifacial or fifth) nerve ; whereby a very an- noying pain is also produced. He, for that reason, advises seeking the nerves that branch from the portio dura, where they emerge from the parotid gland ; or else limit the position of the electrodes to the individual muscles that are affected. He says he finds a slight difference in the exact situation of some of these face motor nerves, in some persons, but that the elec- trodes will soon discover them. In the supra-clavicular region, the electrodes, if placed di- rectly over the collar bone, act on the brachial plexus. If placed on the summit of the supra-clavicular triangle, they are then over the external branch of the spinal accessory nerve of Willis. The phrenic nerve is reached on the anterior surface of the scalenius anticus. Dr. Duchenne also maintains that both nerves and muscles possess very different degrees of excitability; and for that reason