LE SAGE, a modern philosopher, had a memory singularly defective.

Incapable of acquiring languages, and deficient in all those studies which depend on the exercise of the memory, it became the object of his subsequent exertions to supply this deficiency by the order and method he observed in arranging every new fact or idea he obtained; so that in reality with a very bad memory, it appears that he was still enabled to recall at will any idea or any knowledge which he had stored up.

JOHN HUNTER happily illustrated the advantages which every one derives from putting his thoughts in writing, "it resembles a tradesman taking stock; without which he never knows either what he possesses, or in what he is deficient." The late WILLIAM HUTTON, a man of an original cast of mind, as an experiment in memory, opened a book which he had divided into 365 columns, according to the days of the year: he resolved to try to recollect an anecdote, for every column, as insignificant and remote as he was able, rejecting all under ten years of age; and to his surprise, he filled those spaces for small reminiscences, within ten columns; but till this experiment had been made, he never conceived the extent of his faculty.

WOLF, the German metaphysician, relates of himself that he had, by the most persevering habit, in bed and amidst darkness, resolved his algebraic problems, and geometrically composed all his methods merely by the aid of his imagination and memory; and when in the daytime he verified the one and the other of these operations, he had always found them true.

Unquestionably, such astonishing instances of a well-regulated memory depend on the practice of its art gradually formed by frequent associations.