(_a_) The urgency of the need which a commodity satisfies enables the monopolist to charge high prices. Where a community is dependent for life upon some single commodity, as the Chinese on rice, the monopolist is able to obtain a high price for the whole of a supply which does not exceed what is necessary to keep alive the whole population. Thus a monopolist of corn or rice in a famine can get an exorbitant price for a considerable supply. But after the supply is large enough to enable every one to satisfy the most urgent need for sustenance, the urgency of the need satisfied by any further supply falls rapidly, for there is no comparison between the demand of famine and the demand induced by the pleasures of eating. A monopoly of a necessity of life is therefore more dangerous than any other monopoly, because it not merely places the lives of the people at the mercy of private traders, but because it will generally be the interest of such monopolists to limit supply to the satisfaction of the barest necessaries of life. Next to a necessary in this respect will come what is termed a "conventional necessary," something which by custom has been firmly implanted as an integral portion of the standard of comfort. This differs, of course, in different classes of a community. Boots may now be regarded as a "conventional necessary" of almost all grades of English society, and a monopolist could probably raise the price of boots considerably without greatly diminishing the consumption. Half a century ago, however, when boots were not firmly established as part of the standard of comfort of the great mass of the working classes, the power of a monopolist to raise prices would have been far smaller. As we descend in the urgency of wants supplied we find that the comforts and luxuries form a part of the standard of life of a smaller and smaller number of persons, and satisfying intrinsically weaker needs, are more liable to be affected by a rise of price.