Lectures on the Clinical Uses of Electricity, Delivered in University College Hospital

Each variety is susceptible of being applied in several divers ways ; thus, the Franklinic electricity may be charged into a patient isolated on a glass-legged couch ; the patient is then said to be in an " electric bath sparks may be taken from any part of his body by presenting a rounded brass-knob ; or sparks may be discharged at a non-isolated patient by a coxi* ductor attached to a plate friction-machine; or more violent shocks may be given by discharging Leyden jars at the desired Spnfs. The galvanic state may be used as a continuous current, the patient or limb forming part of the circuit. The current is called "inverse," when it goes from extremities towards centres, and " direct," when it goes from centres towards extremities; thus, if we hold the positive pole handle in our ri<rht, hand, and the negative pole handle in our left, the current will be said to be inverse in the right arm and direct in the left. This distinction is of some importance, insomuch that the "inverse" current gradually increases the initability of the muscle and nerve whilst the " direct" current gradually lessens it. The current may be interrupted, either slowly or quickly. The most usual manner of ''interrupting" slowly being by dabbing the skin gently with the sponge handle ; the operator can thus " make" and " break" the current as he likes, and send successive charges of short duration down certain sets of muscles. When rapid interruptions are required some simple meoh inical contrivances are used; such as a cogged wheel with teeth of alternating conducting and non-conducting materials ; or a vibrating wire as in Pulvermacher's " interrupters." The Faradic form is necessarily used as an " interrupted" current since " induced electricity" has but a momentary existence at the making and breaking of the inducting current. The "interrupting" is always done by mechanical arrangement. The numerous apparatus which have been devised need not be described here; one author gives the preference to that known