I shall describe under this head the modus operandi of administering a routine galvanic or faradic bath. As it will become necessary to describe special modes of administration when speaking of the electro-balneological treatment of special diseases, the describing them now would only lead to tautologies that I am desirous of avoiding.

Taking our cue from the indications to be met in each case, it becomes necessary, according to circumstances, to use either the galvanic current, the faradic, or both successively. As modifications of the application of the currents we have to consider 1) their intensity; 2) their direction, and 3) the duration of the application.

The intensity of the galvanic current corresponds directly to the number of cells from which it is derived. It were vain however to attempt to express this in figures, because the electro-motive force of different batteries varies to so great an extent, that a number of cells of some batteries of low intensity yield a current so feeble as to be barely appreciable in the bath, while the same number of cells of a battery of high intensity, furnish a current that few persons can bear without pain. In thus comparing the Hill cell with the Stöhrer cell, I have found the ratio to be about as 1 to 2½, i.e., as intense a current can be derived from twenty-four Stöhrer as from sixty Hill cells—and this is rather below than above the mark. Were all batteries alike in this respect, however, still no particular number of cells could be given as furnishing a current of suitable average intensity for the galvanic bath, because of the excessively great variations in the degree of electro-sensibility of different persons. This is so marked that I have seen persons in the bath tub who could bear no more than six Hill cells, diffused as was the current from these through the water and over the entire body; while on the other hand I have met with male patients on whom a current from thirty-two Stöhrer cells made not the slightest impression, and where I was compelled to supplement the current by that from a ten-cell quantity battery (zinc carbon elements 6 in. long by 4½ wide) in order to make them realize the presence of a current. These gentlemen had no cutaneous anæsthesia.

In view of the facts just stated, I have found it impracticable, when giving directions for the administration of a galvanic bath, to indicate any certain number of cells to be used. I am in the habit of ordering the administration of a “mild,” a “medium” or a “strong” current, as may be required in the respective cases; and in every instance it is the electro-sensibility of the patient that determines the number of cells requisite to obtain the desired result as represented by one of these terms. The same applies also to the faradic current.

To determine the direction of the current is sufficiently simple. Where a descending current is desired, the binding post which represents the electrode at the head of the tub must be connected to the positive pole of the battery, the other binding post to the negative pole; where an ascending current is desired, the reverse of this is done.

The duration of the bath varies with different cases. The average is about twenty minutes, though the time may range from ten minutes to an hour and a half.

Where it is desired to give the patient a galvanic shock, it is only necessary rapidly to reverse the current by means of the commutator. The simultaneous contraction of almost the ENTIRE muscular system that accompanies the reversal of a current of sufficient intensity in the bath, affords a striking illustration of the general effects of the galvanic bath. In cases where paralyzed muscles have lost their faradic irritability, galvanic interruptions are almost indispensable to successful treatment.

I have before ([page 14]) described a “surface board,” which I have devised for the purpose of localizing the current from one of the poles in any portion of the body where required. This proceeding should by no means be looked upon as a “local” method of electrization; on the contrary, it is just as much “general” as the ordinary electric bath. Whereas in local applications the current runs from one point of the body to another, in this case, supposing the spot where the surface board is applied to be the centre, and the rest of the body the periphery, a current runs between every point of the periphery and the centre, its direction being centripetal when the surface board communicates with the negative, centrifugal when with the positive pole of the battery.

The current is felt more or less intensely in proportion to the proximity to the body of the surface board. With the galvanic this is less noticeable than with the faradic current. When, for example, a faradic current of medium strength being employed, the surface board is held about six inches from the abdominal surface, little or no current is felt. Let the surface board be now gradually approximated to the abdomen, and the current will be felt more and more sensibly, until, when about an inch away from the skin, or touching this, its influence becomes so strong as to cause more or less energetic contractions of the abdominal muscles. Where the galvanic current is employed, the skin beneath the surface board will be found more or less reddened after a few minutes’ application; the burning sensation ordinarily accompanying galvanic applications will also be experienced more or less intensely, in proportion to the strength of the current employed.

Where the current is to be concentrated in a manner still more energetic than that described, this can be effected by raising the objective part above the surface of the water, and then applying the surface board. In this way the entire strength of the current is concentrated in one spot, whereas, when the surface board is applied under water, a large portion of current is absorbed by this.