We may now pass from the “frictional” to the other kind—viz., “dynamical” electricity, and we shall begin with the consideration of GALVANI’S experiments and the VOLTAIC PILE. [Illustration: Electric condenser.] FOOTNOTES: [14] GANOT: _Eléments de Physique_. CHAPTER XX. GALVANISM. GALVANI’S DISCOVERY—THE FROGS ELECTRIFIED—EXPERIMENTS—VOLTA’S PILE—THE TEST—ITS USEFULNESS—FARADAY’S “RESEARCHES.” Galvanism owes its origin to the researches of Galvani, the celebrated professor of Bologna, and we are indebted to what was a mere “accident” for our knowledge of this science. Before Galvani’s time there had been many instances adduced of animal electricity. The Rev. F. Lunn, in his article upon Electricity,[15] mentions the fact that fire streamed from the head of Servius Tullius when about seven years of age, and Virgil we know refers to flame emitted by the hair of Ascanius— “Lambere flamma comas, et circum tempora pasci”; and if any one will comb his or her hair with an ebonite comb in the dark, with what is sometimes called an “india-rubber comb,” the hair will give out sufficient light to enable the operator to see himself in a looking-glass. In olden days it is related that a lady when touched with a linen cloth emitted sparks, and the same phenomenon was observable when a bookseller at Pisa removed his under-garment or vest (De Castro). We are all aware of the electricity of the cat and of certain fishes (_see_ Electricity of Animals in sequel), and “torpedos.” Galvani had of course a knowledge of this property, and had occupied himself for some time making experiments upon the electricity in animals. He was not in his laboratory that day when the great discovery was made by means of the edible frog. Galvani’s wife was just then in a very delicate state of health, and in accordance with usage had been ordered soup made from frogs. It is related that some of these animals, ready skinned, were lying upon the laboratory table, for the Professor had been just previously investigating the question of what he opined was “animal” electricity; that is, he fancied that muscular motion depended upon that subtle force.