Genius creates by a single conception; the statuary conceives the statue at once, which he afterwards executes by the slow process of art; and the architect contrives a whole palace in an instant. In a single principle, opening as it were on a sudden to genius, a great and new system of things is discovered. It has happened, sometimes, that this single conception, rushing over the whole concentrated spirit, has agitated the frame convulsively. It comes like a whispered secret from Nature. When MALEBRANCHE first took up Descartes's Treatise on Man, the germ of his own subsequent philosophic system, such was his intense feeling, that a violent palpitation of the heart, more than once, obliged him to lay down the volume. When the first idea of the "Essay on the Arts and Sciences" rushed on the mind of ROUSSEAU, a feverish symptom in his nervous system approached to a slight delirium. Stopping under an oak, he wrote with a pencil the Proso-popeia of Fabricius. "I still remember my solitary transport at the discovery of a philosophical argument against the doctrine of transubstantiation," exclaimed GIBBON in his Memoirs. This quick sensibility of genius has suppressed the voice of poets in reciting their most pathetic passages. THOMSON was so oppressed by a passage in Virgil or Milton when he attempted to read, that "his voice sunk in ill-articulated sounds from the bottom of his breast." The tremulous figures of the ancient Sibyl appear to have been viewed in the land of the Muses, by the energetic description which Paulus Jovius gives us of the impetus and afflatus of one of the Italian improvvisatori, some of whom, I have heard from one present at a similar exhibition, have not degenerated in poetic inspiration, nor in its corporeal excitement. "His eyes fixed downwards, kindle as he gives utterance to his effusions, the moist drops flow down his cheeks, the veins of his forehead swell, and wonderfully his learned ear, as it were, abstracted and intent, moderates each impulse of his flowing numbers."[A] [Footnote A: The passage is curious:--"Canenti defixi exardent oculi, sudores manant, frontis venae contumescunt, et quod mirum est, eruditae aures, tanquam alienae et intentae, omnem impetum profluentium numerorum exactissima ratione moderantur."] This enthusiasm throws the man of genius amid Nature into absorbing reveries when the senses of other men are overcome at the appearance of destruction; he continues to view only Nature herself. The mind of PLINY, to add one more chapter to his mighty scroll, sought Nature amidst the volcano in which he perished. VERNET was on board a ship in a raging tempest where all hope was given up. The astonished captain beheld the artist of genius, his pencil in his hand, in calm enthusiasm sketching the terrible world of waters--studying the wave that was rising to devour him.[A]