The Causes of Prostitution.—As in every commercial transaction, so also in the women-market, two factors are decisive—supply and demand. The demand arises from the fact that to men of the upper classes marriage has become difficult or impossible. Whereas in the case of the lower classes of the population, concubinage offers a substitute for marriage, so that for the men of the lower classes prostitution may be regarded as superfluous, in the case of men of the upper classes prostitution is practically the only available substitute for marriage, so that these men are led to purchase casual and temporary wives from among the women of the lower classes. The supply depends upon poverty, which is the principal cause of prostitution. By this it is not meant to imply that actual destitution is usually the direct and immediate cause of the adoption of a life of prostitution. It is rather that a number of factors, the outcome or the accompaniments of poverty, combine to place girls in a position very favourable to their becoming prostitutes. The environment ............