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logna in 1737. From his youth he was strongly attached to theRoman Catholic religion. He studied medicine under Beccari,Jacconi, Galli, and professor Galeazzi, whose daughter he mar-ried. He was created lecturer on anatomy in the university ofBologna in 176'J. He soon acquired a very high reputation as afianatomist and physiologist, and great crowds attended his lectures.His extensive knowledge, and industry in making experimentsled to a discovery, from which he had the honour of giving hisname to a new subject of philosophical inquiry. Happening tohave some frogs lying on the table of his laboratory, skinned forthe purpose of making soup as a restorative for his wife, who wasin a declining state of health, one of his assistants chanced to bringthe point of a scalpel near the crural nerves of a frog, which wasnear the conductor. Instantly the muscles of the limb were agi-tated with strong convulsions. This was observed by MadameGalvani, a woman of quick understanding, and a scientific turn,and she immediately mentioned it to her husband. He repeated

l the experiment; and soon found that the convulsion only lookplace when a spark was drawn from the conductor, at the time thescalpel was in contact w'ith the nerve. This induced him to gothrough a series of experiments, which have laid the foundation ofGalvanism. Galvani was a man of an amiable character in pri-vate life, and possessed of great sensibility. The death of his wifein 1790, threw him into a profound melancholy. On refusing totake the civic oath exacted by the new constitution of the Cisal-pine Republic , he incurred the deprivation of his posts and dig-nities. A prey to melancholy, and reduced almost to indigence,he retired to the house of his brother James, a man of very re-spectable character, whore he indulged his grief. The republicangovernors, probably ashamed of their conduct towards such a man,passed a decree for his restoration to his professional chair and itsemoluments; but it was then too late, lie died in 1793, on No-vember a, aged sixty, being much lamented by his friends and thepublic.

GALVANISM.

GALVANISM, (so called from Dr. Galvani, the discoverer,)that branch of philosophy which investigates and explains thePhenomena arising from the action or influence of certain bodiesso disposed as to form a continued chain, or circle of communica-tion with each other. Dr. Galvani was led to the discoveries,which gave rise to this department of science, by an incidentalGrcumstance, mentioned in the last ’article, which shewed theefforts of a small quantity of electricity on the nerves and musclesof a trog. From a series of experiments on this subject, principallyperformed on dead frogs, lie found that a small quantity of elec-tricity is capable of bringing the muscles into action, even afterthe animal has been dead a considerable time. He also foundthat independent of any. apparent electricity, the same motionsmay be produced in the deacl animal, or even in a detached limb,merely by making a communication between the nerves and themuscles, with substances that are conductors of electricity. If thecircuit of communication consists of non-conductors of electricity,glass, sealing-wax, and the like, no motion will take place.Similar experiments were also successfully instituted upon othermfimals; and as the power seemed to be inherent in the animalParts, those experiments, or the power which produces the motion°f the muscles in those experiments, were denominated animalelectricity. But it being now fully ascertained, that by the merecontact of metallic and other conducting substances, some elec-tricity is generated, it is evident that the muscular motions in theabove-mentioned experiments are produced by that electricity.

Galvani , in making his experiments, used to skin the legs of■Mrog recently dead, and to leave them attached to a small part ofme spine, but separated from the rest of the body. Any other‘‘mb may be prepared in a similar manner; viz. the limb.is de-prived of its integuments, and the nerve which belongs to it is part-T Lid bare. If the limbs thus prepared, for instance the legs offrog, are situated so that a little electricity may pass through,‘°m, be it by the immediate contact of an electrified body, or byj L ‘ action of electric atmospheres (as when the preparation isPfr'ced within a certain distance of an electrical machine, ami. a?P a !'k is taken from lire prime conductor) ; the prepared legs will..** Instantly affected with a kind of spasmodic contraction, some-‘mes so strong as to jump a considerable way. W hen the eiec-Mcity is caused to pass through the prepared Irog by the mimedi-. m contact of . the electrified body, a much smaller quantity of its a tif"tiriejit to occasion the movements, than when it is made toPass f rom olu , conductor (o another, at a certain di-lance lioin theP r Ppared animal, 'l’lie movements are much stronger when the*' t'etricity is caused to pass through a nerve to the muscle or mus-„ , than through nnv other part. The sensibility of the prepar-u aifi.mai is greatest at first, but it diminishes by degrees till it

I vanishes entirely. Animals with cold blood, and especially frogs,retain that sensibility for several hours, sometimes even for a dayor two. With other animals the sensibility does not la-t long af-ter death, and sometimes not above a few minutes. The likemovements may be produced in the prepared animal without theaid of anv apparent electricity. In an animal recently dead, de-tach one end of a nerve from the surrounding parts, taking care tocut it not too near its insertion into the muscle; remove the inte-guments from over the muscles which depend on that nerve ; takea piece of inclal, as a wire, and touch the nerve with one extre-mity of it, and the muscles with Us other extremity ; on doingwhich you will find that the prepared limbs move in the samemanner as when some electricity is passed through them. This,however, is not the most effectual way of forming the communi-cation ; yet it will generally succeed, and the experiment will an-swer whether the preparation be laid upon conductors or uponelec trics. If the communic ation between the nerve and the mus-cle be formed by the interposition of non conductors of electri-city, such as glass, sealing-wax, &c. then no movements will takeplace. When the application of the metal or metals is continuedupon the parts, the contractions will cease altera certain time, andon removing the metal, seldom, if ever, any contraction is observ-ed. The conducting communication between the muscle andtlie nerve may consist of one or more pieces, and of the same, ormuch better, of different bodies connected together, as metals, wa-ter, a number of persons, and even wood. But it must be ob-served, that the various bodies, which form this circuit, must lieplaced in full and perfect contact with each other, which is doneby pressure, or by the interposition of water, &c. The less per-fect conductors will answer only at first, when the prepared animalis vigorous; but when the power begins to diminish, then themore perfect conductors will only answer, and even these willproduce various effects. The most effectual way that lias hithertobeen discovered of producing those movements in prepared ani-mal parts is by the application of two metals, of which silver andzinc seem upon the whole to lie best, though silver and tin, orcopper and zinc, and other combinations, are not much inferior tothem. If part of the nerve proceeding from a prepared limb iswrapped up in a bit of tin-foil, or only laid upon zinc, and a pu ceof silver laid with one end upon the hare muscle, and w ith (lieother upon the above-mentioned tin or zinc, the motion of the pre-pared limb will lie very vigorous. The two metuL may be placednot in contact with the preparation, but in any other pert of thecircuit, which may be completed by means of other conductors,as water, &c. The best preparation for this expi nment is madein the following manner. Separate with a pair of seiss:;r- ihc headand upper extremities of a frog from tin* ir-t of tin; bud\. Open