Electro-physiology and electro-therapeutics : showing the best methods for the medical uses of electricity / By Alfred C. Garratt.

contain less blood than normal, and yet there is more heat. Hence, if the heat does not arise from an action on the skin, nor yet from the influx of blood and fluids, it must be due to an augmentation of those nervo-electro-cheniical changes which we call vital chemistry, and which are continually going on in ail the tissues of the living organism, but more particularly in the muscles, and which action constitutes their very existence, growth, and life, their wear and repair,or exhaustion and nutrition, much as if an engine were so arranged and endowed as to draw its own water and coal, clear its soot and ashes, oil its own axles, and do its own forging. It is, then, well ascertained that the heat developed in living tissues after treatments by electro-muscular contractions, as more frequently noticed in the paralytic and atrophied, is an increased vital and catalytical action among the tissues and liquids, rather than a chemical action on the surface of the skin. This propo- sition is also fully confirmed by various pathological experience. Two results are determined from the effects of electric cur- rents on enfeebled, relaxed, or paralyzed muscles ; and the first is, an increase of heat, and the second, an increase in size, of the parts so acted upon. The solid structure of muscle fibres imbibes a fluid from the blood, which is discovered to be, at times, variable in composition. If this muscular fluid is taken from a muscle that has been long at rest, it will be found to give a neu- tral reaction ; but after labor or active electric excitation of the muscle, the fluid will then give an acid reaction, in consequence of an increased absorption of oxygen, and consequent oxidation and formation of carbonic acid. This can be proved by actual experiment, if we measure the quantity of oxygen absorbed, and carbonic acid exhaled, by the muscular substance of the frog's thighs which have been skinned and suspended in closed glass vessels filled with air or oxygen; for we find that if the muscles in some of the vessels are electrized, and the others not, the quantity of the gases absorbed and exhaled by the electrized muscles is found to be more than double that absorbed and ex- haled during the same time by the quiescent muscles in the other vessels. From many fair trials, we know, at least, that