It is often mischievous as well as anomalous in its action. Under civilization with its division of labour, the various functions of mind and body are very unequally exercised. There is overwork or misuse of one part and disuse and neglect of others, leading to the partial breakdown or degeneration of various organs and to general deterioration of health through disturbed balance of the constitution. The brain, or rather particular parts of it, are often over-stimulated, while the body is neglected. In many ways education and civilization foster nervousness and weakness, and undermine the rude natural health and spirits of the human animal. Alcohol, tobacco, tea, coffee, extra brain work, late hours, dissipation, overwork, indoor life, division of labour, preservation of the weak, and many other causes, all help to injure the modern constitution; so that the prospect of cumulative intensification of these evils by the additional influence of use-inheritance is not an encouraging one. It is true that modern progress and prosperity are improving the people in various respects by their direct action; but if use-inheritance has any share in effecting this improvement it must also transmit increased wants and more luxurious habits, together with such evils as have already been referred to. As depicted by its defenders, use-inheritance transmits evils far more powerfully and promptly than benefits. It transmits insanity and shattered nerves rather than the healthy brain which preceded the breakdown. It perpetuates, and cumulatively intensifies, a deterioration in the senses of civilized men, but it fails to perpetuate the rank vigour of various plants when too well nourished, or the flourishing condition of various animals when too fat or when tamed. It already transmits the short-sight caused by so modern an art as watchmaking, but so fails to transmit the long-practised art of seeing (as it does of walking and talking) that vision is worse than useless to a man until he gradually acquires the necessary but non-transmitted associations of sensation and idea by his own experience. In a well-known case, a blind man on gaining his sight by an operation said that "all objects seemed to touch his eyes, as what he felt did his skin"--so little had the universal experience of countless ages impressed itself on his faculties. Under normal healthy conditions use-inheritance is so slow in its action that "several generations" must elapse before it produces any appreciable effect, and then that effect is only precisely what selection might be expected to bring about without its aid. Strong for evil and slow for good, it can convey epilepsy promptly in guinea pigs, but transmits the acquirements of genius so poorly that our best student of the heredity of genius has to account for the frequent and remarkable deterioration of the offspring by a theory which is strongly hostile to use-inheritance. It