So intense indeed has been this influence, that Pliny contemplated the volcanic philosophy amidst the ashy cloud of Vesuvius by which he was destroyed. And Archimedes was so intent in solving a problem, during the siege of Syracuse, that no sense of danger impelled him to avoid the storm, or fly from the dagger of the assassin. While Parmegiano was painting at Rome the “Vision of St. Jerome,” which now adorns the National Gallery of England, the famous siege of that city was concluded by its spoliation. Yet Parmegiano (absorbed with his painting) was unconscious of the tumult, until his _studio_ was burst open by some of the soldiers of the enemy. A similar story is told, also, of Protogenes, when Demetrius was laying siege to Rhodes. CAST. The flappers of Laputa would soon have dispelled this reverie. EV. But if they had thus flourished their official bladders, perhaps the “Principia Mathematica” had not been written; for Newton explained the extent of his discoveries by his “always thinking unto them.” Somewhat like the effect of intense study on the mind, the muscles of the limbs will be influenced _by one long-directed habit_. Paganini was observed, on board a steam-boat, constantly to repose on the sofa. During this state of reverie, his left arm assumed the peculiar attitude in which he held his violin, until he saw that he was noticed, when he altered its position. The right hand of Benjamin West, of which I saw a posthumous model at Lord de Tabley’s, appeared to have taken that form in which he was wont to hold the pencil. By this concentration, this full possession of the mind, the wildness of fancy in the dark is often the source of terror; but this is ever lessened or dispelled by any sound or sight which presents a subject to the _perceptive_ faculty. Such is the sudden glimmer of a light, the barking of a dog, or the almost instinctive effort of the school-boy, “Whistling aloud to keep his courage up.” All these cases, then, indicate concentration of mind. “Mental conception is uninfluenced by conscious perception.” I may add, that, in the heat of engagement, soldiers and sailors are often unconscious of being even seriously wounded. In the battle of Lake Thrasymene, the armies of Rome and Carthage were so absorbed in the tumult and din of war, that an earthquake, which spread desolation around them, was unheeded by these determined soldiers. IDA. I have gleaned enough from your illustrations, Evelyn, to believe that we may explain by them that solemn and last reverie of the dying, when all other ideas have ceased to influence, but the _most impressive_— “The ruling passion strong in death;” when earthly life is on the wane, and the spirit, in this expiring thought, takes its last farewell of the flesh. I remember some beautiful evidences of this influence. It was observed that Porson, after a paralytic fit, scarcely uttered a word of English; but to the last moment spoke _Greek_ fluently.