in this part of medicine. I am ready to acknowledge that great caution ought to be employed in performing such experiments; and for this reason I purpose, in the third part of the present work, to lay before the reader the reflections and observations of various ingenious men who have made this department of Galvanism an object of their researches. But before I proceed further, I think it necessary to deduce from what has been already said a few general corollaries. COROLLARY I. The muscles are affected by the action of the pile in a much more powerful manner when they are laid entirely bare, and when the arc is made to penetrate to a considerable depth in their substance. COROLLARY II. These convulsions are increased in proportion to the number of the points of contact between the arc and the muscle. COROLLARY III. In many cases, muscular contractions are obtained by forming an arc from one muscle to another. COROLLARY IV. Muscular contractions are almost always speedily obtained by the pile, even when the means proposed by Haller fail to produce them. COROLLARY V. The heart, which, according to Haller’s principle, is the first muscle that receives life and the last to lose it, in comparison of the other muscles, can with difficulty be made to feel the influence of the Galvanic action; while the other muscles always retain, a long time after death, that vital force which it has never been found possible to excite but by the impulse of Galvanism. COROLLARY VI. The partisans of Haller, to excite these contractions, often employ stimulants, which alter the texture of the muscular fibre, and destroy its continuity; an inconvenience which may be avoided by applying Galvanism. COROLLARY VII. As the kinds of apparatus before mentioned are not applied to the spinal marrow alone, but to the different nerves of the animal machine, they may afford to the anatomist an experimental myology; by means of which he can render sensible to the eye the fixed and moveable points of the muscles, and the real extent of their action. COROLLARY VIII. The experiments made on the bodies of persons who died a natural death, are of the greatest importance to physiology. I am strongly inclined to think that, by pursuing these researches more in detail, they will one day make us better acquainted with the character of the vital powers, and the difference of their duration, according to diversity of sex, age, temperament and disease, and even according to diversity of climate and to the nature of the atmosphere. PART THE THIRD. ON THE POWER OF GALVANISM AS APPLIED TO MEDICINE.