Page:Popular Science Monthly Volume 19.djvu/570

554

Messrs. Editors.

EAR SIRS: On pages 28 and 29 of the May number of the "Monthly" there is given an explanation of the fact that some of the Saratoga springs spout intermittently, which seems to be entirely inadequate.

The author says: "As the water flows into the pocket from the surrounding inlets it gradually rises above the outlet, which results in the compression of the gas between the roof of the cavity and the surface of the accumulating water; when the force of compression reaches its maximum, it drives the water from the chamber up through the tube, from which it escapes in some instances to a distance of thirty feet in a vertical direction. After the pent-up water and gas have escaped, the spouting ceases," etc. There is nothing in the explanation or the diagram referred to in connection with it that would warrant the conclusion that gas thus pent up would relieve itself of pressure with a suddenness sufficient to produce the spouting. On the contrary, the flow of the spring, under the conditions stated, ought to be very uniform instead of intermittent. If the inflowing water "gradually rises above the outlet," the gas in the upper portion of the pocket would be as gradually compressed, and its reaction upon the water would tend, precisely like that of the air in the air-chamber of the common force-pump, to steady the outflowing stream and to prevent spouting.Very respectfully,

Messrs. Editors.

the article entitled "Mechanical Vibration as a Remedy in Neuralgia," in the Miscellany Department of the June number of "The Popular Science Monthly," is likely to elicit further inquiry, on account of the wellnigh universal interest in the conclusions set forth, I may be pardoned for offering a few facts pertinent to the same subject.

The control of neuralgia, and indeed of pain in almost any chronic form, by mechanical vibration, as asserted by M. Boudet dc Paris and Dr. Granville, has been so thoroughly demonstrated as no longer to admit of question, and should be considered as well settled as any principle in medicine. Nor is the control of this agent over the nerves limited to pathological conditions. It is an anæsthetic as powerful as simple. Under its influence I have repeatedly witnessed such injury to the skin and flesh as would ordinarily produce unbearable pain, without in the least affecting the consciousness of the subject of the experiment. Indeed, so complete may the anæsthetic effect be made, that I have no doubt, were it possible to secure other mechanical conditions necessary, the capital operations of surgery might be painlessly performed under its influence. The same agent is also efficacious in removing obstinate insomnia.

The essential facts presented by M. Boudet de Paris and Dr. Granville, especially those relating to therapeutics, were given by the writer in considerable detail, in the "New York Medical Journal" (Appletons'), about ten years ago. These were then presented as the result of several years of experimenting with the agency in question, to determine the forms of apparatus required (which was found to admit of considerable variety, providing only that due rapidity of motion and shortness of stroke were preserved), and the efforts of varied methods of application in different pathological conditions of the nervous system. These articles were afterward published in book form, entitled "Paralysis and other Affections of the Nerves, and their Cure by Transmitted Energy."

The hypothesis of M. Boudet de Paris, that abnormal vibrations of the neuralgic nerve are opposed and annulled by mechanical vibrations, seems to imply a fixed rate for each of the differing conditions. In practice, it is found that the removal of pain is progressive, and the anæsthetic effect increases with increase of rate of mechanical vibration—which appears unfavorable to this hypothesis.

The efficacy of mechanical vibration to abolish pain may probably be explained on physiological grounds easily understood by all. For the application of this agent is in reality a supply of energy, which is immediately transformed into and merges with preëxisting physical operations of the vital system—of course, aiding to perfect these actions. No portion of such transmitted energy is lost—it only changes its form—and reappears in increase of temperature,