are so frequently produced in families in which the practice of those arts and sciences is familiar. The same aptitude may be shared by several members of the family, who will remain in the secondary rank, while a single one rises above them all. It is the aptitude, not genius, that is hereditary, while Mr. Galton has constantly confounded the two. In the other orders of invention, as in poetry and eloquence, there is nothing inconsistent with a solitary instance of genius being produced in a family that does not seem to have been prepared for it. The preparatory training, the special aptitude, are less necessary in them. It is enough if the national language has reached a degree of clearness and vigor in which it can give perfect expression. Generally, the great writer blossoms out alone. He seems to appear, an unexpected phenomenon, in a succession of modest generations, the uniform course of which he breaks at a blow. Sometimes similar aptitudes may be found among other members of the family, but the fact is without significance or consequences. Bossuet, Pascal, Molière, Voltaire, Jean Jacques Rousseau, Byron, and Goethe, however we may try to account for them, can not be explained by heredity. They are the first and the last in the families that produced them, without any visible transmission of superior gifts. Going back in history, but still keeping to modern times, are not Dante, Milton, and Shakespeare also solitary great ones, who can not be satisfactorily accounted for, either by organic evolution, the intellectual medium, or generation? All those external conditions of genius that have been so often analyzed and described may have prepared for the event and primed for the occasion. The last turn was still wanting, the supreme gift that should be decisive over all the rest, and bring it about that among so many heads in the same family or the same nation, equally predestined by the same concurrence of circumstances, one only should have been chosen, and that the light should have shone upon that elect head only; and we may keep on asking, Why on that head, and not on another? No, to this day the great gift of inspiration in science, poetry, and art has not revealed its secret. Those sovereign minds, precisely by what they possess that is incommunicable, rise high and alone above the flood of generations which precede and follow them, and by reason of this superior side of their nature they do not belong to nature. Those exalted originals in mind who tower above mankind have no fathers and leave no sons in the blood. Notwithstanding Mr. Galton, the least hereditary thing in the world is genius.
M. de Candolle appears to us to have exactly analyzed the origin and conditions of the kind of mental heredity in a slighter degree that we might represent by the words talent, vocation, and aptitude. While he does not deny the influence of heredity in the development of vocations, especially of scientific vocations, which are the special object of his study, he does not declare it exclusive and decisive. After ma-
- "Histoire des Sciences et des Savants depuis Deux Siècles."