Not less patient, resolute, and persevering was Sir Charles Bell in the prosecution of his discoveries relating to the nervous system. Previous to his time, the most confused notions prevailed as to the functions of the nerves, and this branch of study was little more advanced than it had been in the times of Democritus and Anaxagoras three thousand years before. Sir Charles Bell, in the valuable series of papers the publication of which was commenced in 1821, took an entirely original view of the subject, based upon a long series of careful, accurate, and oft-repeated experiments. Elaborately tracing the development of the nervous system up from the lowest order of animated being, to man—the lord of the animal kingdom,—he displayed it, to use his own words, “as plainly as if it were written in our mother-tongue.” His discovery consisted in the fact, that the spinal nerves are double in their function, and arise by double roots from the spinal marrow,—volition being conveyed by that part of the nerves springing from the one root, and sensation by the other. The subject occupied the mind of Sir Charles Bell for a period of forty years, when, in 1840, he laid his last paper before the Royal Society. As in the cases of Harvey and Jenner, when he had lived down the ridicule and opposition with which his views were first received, and their truth came to be recognised, numerous claims for priority in making the discovery were set up at home and abroad. Like them, too, he lost practice by the publication of his papers; and he left it on record that, after every step in his discovery, he was obliged to work harder than ever to preserve his reputation as a practitioner. The great merits of Sir Charles Bell were, however, at length fully recognised; and Cuvier himself, when on his death-bed, finding his face distorted and drawn to one side, pointed out the symptom to his attendants as a proof of the correctness of Sir Charles Bell’s theory.