and of these I will mention the leading ones only. A requisite of all chemicals to be employed is their ready solubility in water. Of substances intended for absorption[3] I have used but three, viz: iron, iodine, and extract of malt. The first of these I have employed in anæmic and enfeebled conditions generally, but especially in chlorosis and chlorotic hysteria, with marked success. It has the advantage, when administered in this manner, not only of sparing the alimentary canal the frequently injurious task of becoming the medium of its assimilation, but, in addition to this, I believe that it can in this way be introduced into the blood much more rapidly and in larger quantities than when given by the mouth. The preparation which I have found, all things considered, the most eligible for this purpose, is the “tartrate of iron and ammonia.” This is very readily soluble, leaving no deposit, is assimilable, and not too expensive for the purpose. As, in my experience at least, it leaves nothing to wish for, I would consider it superfluous to discuss in this connection any of the other ferruginous preparations.

Iodine I have employed with a view to its absorption in rheumatism and gout. I cannot speak favorably of it in this connection. I have not in a single instance found a bath charged with iodine, either in the form of the tincture or of iodide of potassium, followed by results in any way differing from those of the simple galvanic bath employed in the same cases.

Extract of malt I have employed as a roborant, either alone or in conjunction with iron, in cases of debility and malnutrition, and found it of service.

Where the absorption of substances is aimed at, the galvanic current must be employed.

Where we add substances to an electric bath with a view of producing some special action on the skin, we may be guided by the same principles that govern ordinary balneology. Thus to obtain counter-irritant effects, we may add mustard or common salt; to render the bath alkaline, bicarbonate of potassa or soda, etc., etc.

An important object to be furthered by the addition to the galvanic bath of chemicals, is the elimination from the system of certain metallic substances. It will be found here that in practice we have to deal chiefly with two substances, viz: mercury and lead. That the elimination of these bodies by means of the galvanic bath is feasible, I shall endeavor to demonstrate further on. At present I have simply to consider the chemicals adapted for the purpose, and the manner of using them.

To facilitate the extraction from the system of mercury, nitric-acid has been recommended by those who have heretofore instituted this treatment. While I cannot positively deny that this substance may aid in the elimination of the metal, I am compelled to state, after its trial in several cases, that I have obtained equally good results from the simple galvanic bath. In the light of my own limited experience, therefore, I cannot insist on the necessity of adding any chemical to a galvanic bath which is administered for the purpose of extracting mercury from the body.

Where the elimination of lead is the object aimed at, I am, on the other hand, satisfied of the utility of adding certain chemicals to the water of the bath. Sulphuric acid has been suggested and used for this purpose. I can say nothing respecting its usefulness, as I have never tried it. Indeed, the results with iodide of potassium added to the bath have been so satisfactory, that I have had no occasion to try any other chemical, although almost any other of the preparations of iodine would probably answer equally well. The chemical affinity of iodine for lead affords a ready explanation of its usefulness in this respect. One ounce of iodide of potassium to each bath appears to me a suitable quantity.

I have had no personal experience with any other cases of chronic metallic intoxication than those with lead and mercury.

The absorption of morbid deposits (plastic exudations, etc.) can be materially furthered by adding to a galvanic bath some resolvent—above all, iodine.

I have said above (page 26) that I had found no perceptible benefit from the addition of this substance to the galvanic bath in cases of rheumatism or gout. The contrary holds good however with respect to the frequent sequence of these diseases—articular deposits. When the acute, and to a great extent the subacute symptoms have subsided—and in chronic cases especially, and the disease has left effusions in various joints, iodine, which when employed in this manner, appears to have little or no influence on the pain accompanying these complaints, is a powerful adjuvant in promoting the absorption of the deposits. In chronic synovitis and all other articular affections accompanied by exudation, the same holds good.

I have no doubt that future advances in this branch of science will develop the utility of numerous other drugs and chemicals as additions to the galvanic bath.—Before leaving this subject I must call attention to the influence which the addition to the bath of certain substances has on the conductivity of the water, resp. thus: the action of the current on the patient. I have found that when I caused salt or bicarbonate of soda to be added to the bath, the conductivity of the water became so much increased, so disproportionately greater than that of the body, as to render necessary the employment of very powerful currents in order to cause the patient to feel them.

CHAPTER III.

PHYSIOLOGICAL EFFECTS.

In accordance with the plan of the present work, the remarks I shall offer under this head are by no means intended to comprise all that is known at the present day of the physiological effects of electricity in general. It was my purpose when I undertook to write these pages, to offer to the profession a book confined to one subject; not a compilation, but a volume made up almost if not wholly of original matter, chiefly, if not entirely the result of my own observations and experience. For the general physiological effects then of electricity as well as for the theories of its action, I refer those interested to the many excellent works on the subject that have appeared within the last few years. I will treat here only of the physiological