=The Merchant Marine.=—In order that a country may build up a profitable foreign trade it should have vessels of its own in which to carry exports and imports. Trade that depends entirely upon the use of foreign vessels is insecure, because the outbreak of war between two or more foreign countries may keep these ships at home. So the development of American maritime commerce has seemed to make desirable the maintenance of a merchant fleet under the American flag. [Sidenote: Early American shipping.] Since the Revolution there has always been such a fleet; sometimes it has been large, but more often it has been small.[168] After 1915, when the German submarine campaign resulted in the wholesale sinking of British and French merchant vessels, the demand for ships became acute. [Sidenote: The building of ships during the war.] American shipyards once more grew busy and expanded rapidly. In 1916, moreover, Congress passed a Shipping Act, designed to foster the growth of the merchant marine, and when the United States entered the war in 1917 an Emergency Fleet Corporation was created to build a great flotilla of vessels at the public cost and a Shipping Board to operate them. The work was not completed when the war came to an end, nevertheless several hundred vessels were added to the list of America’s ocean carriers. As a result of these efforts the merchant marine of the United States is once more the second largest in the world; but the problem now is to keep these ships busy. Foreign trade began to fall off after the American forces had been brought back from Europe and hundreds of the new ships have remained tied up in American harbors. Some have been sold to private companies; others have been operated by private companies under lease; still others are being operated directly by the Shipping Board.[169] =The Bureau of Foreign and Domestic Commerce.=—The progress of foreign commerce depends not only upon ships and ports but upon the possession of accurate knowledge concerning the course of markets and prices abroad. Data on such matters are gathered, as has been pointed out, by the American consular service. [Sidenote: Statistics of trade—their value.] This is supplemented, however, by statistics collected for the Bureau of Foreign and Domestic Commerce at Washington, an office which is maintained to provide American business men with accurate and up-to-date information concerning every branch of foreign commerce. The bureau collects and translates the tariff laws of foreign countries, makes investigations into the cost of producing goods both in America and abroad, and studies all possible methods of making American foreign trade more profitable. It affords a good illustration of the way in which the government, without itself engaging in trade, may assist the private enterprises of the people.