The tin-plate industry practically had its origin in the United States, in 1892, under the McKinley tariff. As competition increased, prices and the differential fluctuated and declined. At the end of 1898 the tin-plate company was formed and prices at once started upward with a rapid increase in the differential. Cause may, in a measure, be mistaken here for effect. In these cases the part of the rise in price due to the rise of materials is not brought about by the trust. The differential represents its part of the productive process and its source of profits. The power to make the differential high is due in part to the general conditions of business in the last three years considered. The profits of all industries in those years increased. While prices may have risen partly because the trust was formed, it may have been possible to form the trust because prices were rising. The general conclusion is that trust prices are always raised when, and to the extent that, control is secured. They are lowered below normal prices when competition becomes troublesome. Fluctuation of prices probably has been more rapid and more spasmodic under trusts than it has been under ordinary competitive conditions. [Sidenote: Effective trusts injure various producers] 2. _A large degree of monopoly control may lower the incomes of producers of materials, the value of competitive plants, and prices in special local markets._ A strong selling monopoly tends to become also a buying monopoly. A great industry using great quantities of materials may either own the sources or purchase from small producers. The steel trust owns mines, and ships and railroads to bring the ore to the furnaces; but the tobacco trust buys from the farmers. If the packing, refining, and marketing of a product is monopolized, the sellers of the raw or partly finished product are subject to one-sided competition. The small producers of tobacco, of crude oil, and of anthracite coal claim that the effect of the trusts is to give them lower prices for their products. Some have been severely punished by the monopolies for refusing to take the first offer made. Monopoly is thus likewise able to purchase competing plants at ridiculously small sums, by first making them valueless through fierce price-cutting, or by threats of it. "Rich" is often a relative term, and it is said that many a small millionaire producer has anxiously waited to see whether the great trust would next turn its attention to him. [Sidenote: The persistence of competition reducing prices]