It was the view of the tomb of Virgil which so powerfully influenced the innate genius of BOCCACCIO, and fixed his instant decision. As yet young, and in the neighbourhood of Naples, wandering for recreation, he reached the tomb of the Mantuan. Pausing before it, his youthful mind began to meditate. Struck by the universal glory of that great name, he lamented his own fortune to be occupied by the obscure details of merchandise; already he sighed to emulate the fame of the Roman, and as Villani tells us, from that day he abandoned for ever the occupations of commerce, dedicating himself to literature. PROCTOR, the lost Phidias of our country, would often say, that he should never have quitted his mercantile situation, but for the accidental sight of Barry's picture of "Venus rising from the Sea;" a picture which produced so immediate an effect on his mind, that it determined him to quit a lucrative occupation. Surely we cannot account for such sudden effusions of the mind, and such instant decisions, but by the principle of that predisposition which only waits for an occasion to declare itself. Abundant facts exhibit genius unequivocally discovering itself in youth. In general, perhaps, a master-mind exhibits precocity. "Whatever a young man at first applies himself to, is commonly his delight afterwards." This remark was made by HARTLEY, who has related an anecdote of the infancy of his genius, which indicated the manhood. He declared to his daughter that the intention of writing a book upon the nature of man, was conceived in his mind when he was a very little boy--when swinging backwards and forwards upon a gate, not more than nine or ten years old; he was then meditating upon the nature of his own mind, how man was made, and for what future end. Such was the true origin, in a boy of ten years old, of his celebrated book on "The Frame, the Duty, and the Expectation of Man." JOHN HUNTER conceived his notion of the principle of life, which to his last day formed the subject of his inquiries and experiments, when he was very young; for at that period of life, Mr. Abernethy tells us, he began his observations on the incubated egg, which suggested or corroborated his opinions.