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Rh electricity, and that Galvani was right in many of his views.

One branch of science often helps another. By the discovery of the influence of a current of electricity on a magnetic needle, made, in 1820, by Oersted, the galvanometer or multiplier became possible. Nobili, about 1825, constructed such an instrument for physiological purposes, and again demonstrated the muscle-current. In 1837, Matteucci enriched the subject by many beautiful investigations, and, in 1841, du Bois Reymond took it up with rare enthusiasm, and from that year to the present year has laboured on it with much success. One feels, after reading du Bois Reymond's monographs, that he has left little for the gleaners in this great harvest.

How striking is it, my young friends, that the splendid results of modern electrical science, with which we are familiar every day, flowed, in no small degree, from the first physiological experiments of Galvani. Electric lighting, the application of electricity to- the construction of motors, and the thousand ways in which this mysterious thing is becoming the servant of man, sprang from discoveries that date from