CHAPTER VII.
ELECTRICITY.
Electricity is the second means which I have made use of for the purpose of exercising muscles in persons at rest.

It has also an additional value, of which I shall presently speak.
In order to exercise the muscles best and with the least amount of pain and annoyance, we make use of an induction current, with interruptions as slow as one in every two to five seconds, a rate readily obtained in properly-constructed batteries.[24] This plan is sure to give painless exercise, but it is less rapid and less complete as to the quality of the exercise caused than the movements evolved by very rapid interruptions.

These, in the hands of a clever operator who knows his anatomy well, are therefore, on the whole, more satisfactory, but they require some experience to manage them so as not to shock and disgust the patient by inflicting needless pain.

The poles, covered with absorbent cotton well wetted with salt water, which may be readily changed, so as not to use the same material more than once, are placed on each muscle in turn, and kept about four inches apart.

They are moved fast enough to allow of the muscles being well contracted, which is easily managed, and with sufficient speed, if the assistant be thoroughly acquainted with the points of Ziemssen.