d) Chemicals. Where these are added to the water of the bath, it is for one of three purposes: viz. 1)—To exercise a direct therapeutic influence on the patient, either internally by being absorbed, or externally by their action on the skin; 2)—Through chemical affinity to aid in eliminating certain metallic substances from the body; or 3)—To further the absorption of morbid deposits. The various indications in these respects will be treated of in their proper places.
e) The Batteries. In the choice of this, the most important part of the electro-balneological apparatus, the greatest circumspection is necessary. Inferior instruments and such as are liable to get out of order frequently, have time and again been the means of discouraging the beginner in electro-therapeutics, and causing him to abandon the study of an art, the pursuit of which would have well repaid him for all his labor. Fortunately our manufacturers here in New York turn out very good instruments, and if a physician purchases an inferior one, the fault is his own.
Two different currents are required for the baths, viz. 1)—The galvanic, which may be employed either in the constant or interrupted (by means of a rheotome) form; and 2)—the faradic or induced current. Several manufacturers of this city turn out good and serviceable faradic instruments. Those which I have been in the habit of using for some years past are manufactured by the Galvano-Faradic Manufacturing Company, and they have given me unvarying satisfaction. By means of a recently introduced attachment to their batteries, termed the “fine adjustment,” a current of exquisite “fineness” (rapidity of interruption) is obtained, thus removing the only inferiority that has heretofore distinguished American from the best imported instruments. The instrument is very easy of management, and its liability to get out of order very small.
As however the galvanic current is of vastly greater importance in a therapeutic respect, than the faradic, so also much greater care is required in the choice of a galvanic than a faradic battery. In making choice of a galvanic battery, we have to consider its relative quantity, intensity, constancy, permanency, economy of running expenses, and facility of management. We cannot be guided here by the same considerations that guide us in the choice of a battery for office use, where the séances are usually brief and the elements taxed not nearly so much as in the administration of baths. It is not within the scope of this work to enter into a description of the various galvanic batteries that are in use. Neither do I believe that, in a therapeutic sense, there is much difference between the various batteries ordinarily found described in text-books on electro-therapeutics.
Where the battery is to be stationary, a zinc-copper battery, such as the Hill battery for example, is preferable both on account of its constancy and the economy of running it. Of this there should be fully sixty cells, communicating with the bath through a current selector, by means of which the current from any desired number of cells can be obtained. The electro-susceptibility of different individuals varies to such an extent that this is absolutely necessary. Where a portable battery is desired, the Stöhrer zinc-carbon battery will be found the most useful.
I have mentioned these two batteries simply because I have them in use, and they give me satisfaction. There are many others, however, that will answer equally well. On the whole, any battery possessing quantity and intensity in a medium degree will answer.
Footnotes:
[1] A written description can never convey so true an idea of anything, as an ocular inspection. I will therefore say that it will afford me much pleasure to show any member of the profession the apparatus I am about to describe, at my residence.
CHAPTER II.
MODE OF ADMINISTRATION.