Another army had preceded them, armed with picks and shovels, trowels and axes. It was an army of tool chests, building gear and rails. More than one western port of France, slumbering in its ancient ways, had to be transformed, to give proper entrance to the shiploads of soldiers from the New World, with their mountainous equipment, and new roads had to be cut through France to convey them to the front. One regiment was of foresters, with knocked-down sawmills, who went into the woods of France to cut down trees and shape them into timbers for building large docks. Another corps of advance guards were the American engineers, later organized into five regiments and nineteen battalions, all engaged in railroad construction and operation to facilitate the movement of American troops. So with new and spacious gateways, which transformed the restricted port facilities of the French coast towns, and with huge warehouses, ordnance depots and barracks neighboring the new docks, the American troops found an ingress on French soil and accommodation for themselves and their leviathan equipment in keeping with the vast scheme of warfare that represented American belligerency. From the French ports ran a double line of railroad which was extended by American army engineers to the battle front. The use of these preexisting lines for American troops called for the additional construction of hundreds of miles of trackage for yards, sidings, and switches. Thus was called into being the United States Military Railroad in France. It started from the seaport terminals, with their new docks verdant with the rawness of fresh-cut timber, with their tipples and cranes and wharf houses and warehouses, and spread over a mass of tracks that meandered and forked into division yards, curved on to divergent lines or connected with light railways at the fighting front some 600 miles distant. With new ports and new railroad systems virtually constructed for their passage, the American troops moved to their allotted places at the front under conditions that gave their journey an uncommon éclat. They were sorely needed, for one thing, and, for another, preexisting port and transit facilities did not suffice to bear them to their destination. A new path had to be blazed for the armed entrée of the New World into the Old World. [Illustration: Military establishments in the United States.]