The same character existed in France, where DE SERRES, in 1599, composed a work on the cultivation of mulberry-trees, in reference to the art of raising silkworms. He taught his fellow-citizens to convert a leaf into silk, and silk to become the representative of gold. Our author encountered the hostility of the prejudices of his times, even from Sully, in giving his country one of her staple commodities; but I lately received a medal recently struck in honour of DE SERRES by the Agricultural Society of the Department of the Seine. We slowly commemorate the intellectual characters of our own country; and our men of genius are still defrauded of the debt we are daily incurring of their posthumous fame. Let monuments be raised and let medals be struck! They are sparks of glory which might be scattered through the next age! There is a singleness and unity in the pursuits of genius which is carried on through all ages, and will for ever connect the nations of the earth. THE IMMORTALITY OF THOUGHT EXISTS FOR MAN! The veracity of HERODOTUS, after more than two thousand years, is now receiving a fresh confirmation. The single and precious idea of genius, however obscure, is eventually disclosed; for original discoveries have often been the developments of former knowledge. The system of the circulation of the blood appears to have been obscurely conjectured by SERVETUS, who wanted experimental facts to support his hypothesis: VESALIUS had an imperfect perception of the right motion of the blood: CAESALPINUS admits a circulation without comprehending its consequences; at length our HARVEY, by patient meditation and penetrating sagacity, removed the errors of his predecessors, and demonstrated the true system. Thus, too, HARTLEY expanded the hint of "the association of ideas" from LOCKE, and raised a system on what LOCKE had only used for an accidental illustration. The beautiful theory of vision by BERKELEY, was taken up by him just where LOCKE had dropped it: and as Professor Dugald Stewart describes, by following out his principles to their remoter consequences, BERKELEY brought out a doctrine which was as true as it seemed novel. LYDGATE'S "Fall of Princes," says Mr. Campbell, "probably suggested to Lord SACKVILLE the idea of his 'Mirror for Magistrates'." The "Mirror for Magistrates" again gave hints to SPENSER in allegory, and may also "have possibly suggested to SHAKSPEARE the idea of his historical plays." When indeed we find that that great original, HOGARTH, adopted the idea of his "Idle and Industrious Apprentice," from the old comedy of _Eastward Hoe_, we easily conceive that some of the most original inventions of genius, whether the more profound or the more agreeable, may thus be tracked in the snow of time.