A Trust, or other company, or a single individual who has a complete monopoly of a class of goods for which there is a demand, will strive to fix that price which shall give him the largest net profit on his capital. The question with him will be simply this, "How many articles shall I offer for sale?" If he offers only a small number the competition of more urgent wants among the consumers will enable him to sell the small number at a high price. Assuming, for the moment, that the production of these articles was subject to the law of constant returns--_i.e._, that a few things were produced relatively as cheaply as many, this small sale would give the highest rate of profit on each sale, for the "marginal utility" of the supply would be high and would enable a high price to be obtained for the whole supply. But if he possesses large facilities of production it may pay him better to sell a larger number of articles at a lower price with a lower rate of profit on each sale, because the aggregate of a larger number of small profits may yield a larger net profit on his whole capital. How far it will pay him to go on increasing the supply and selling a larger number of articles at a lower price will entirely depend upon the effect each increment of supply exercises upon demand, and so upon prices and profits. Everything will hinge upon the "elasticity of demand" in the particular case. If the object of the monopoly satisfies a keen, widely-felt want, or stimulates a craving for increased consumption among those who take off the earlier supply, a large increase in supply may be attended by a comparatively small fall in prices. Sometimes a large increase of supply at a lowered price will, by reaching a new social stratum, or by forcing the substitution of this article for another in consumption, so enlarge the sale that though the margin of profit on each sale is small, the net profit on the whole capital is very large. In all such cases of great elasticity it may pay a monopolist to sell a large number of articles at a low price.