Even more directly did the War stimulate our industrial development. Perhaps the greatest effect was the way in which it changed our transportation system. The mere necessity of constantly transporting hundreds of thousands of troops and war supplies demanded reconstruction and reequipment on an extensive scale. The American Civil War was the first great conflict in which railroads played a conspicuous military part, and their development during those four years naturally left them in a strong position to meet the new necessities of peace. One of the first effects of the War was to close the Mississippi River; consequently the products of the Western farms had to go east by railroad, and this fact led to that preeminence of the great trunk lines which they retain to this day. Almost overnight Chicago became the great Western shipping center, and though the river boats lingered for a time on the Ohio and the Mississippi they grew fewer year by year. Prosperity, greater than the country had ever known, prevailed everywhere in the North throughout the last two years of the War. So, too, feeding and supplying an army of millions of men laid the foundation of many of our greatest industries. The Northern soldiers in the early days of the war were clothed in garments so variegated that they sometimes had trouble in telling friend from foe, and not infrequently they shot at one another; so inadequately were our woolen mills prepared to supply their uniforms! But larger government contracts enabled the proprietors to reconstruct their mills, install modern machines, and build up an organization and a prosperous business that still endures. Making boots and shoes for Northern soldiers laid the foundation of America's great shoe industry. Machinery had already been applied to shoe manufacture, but only to a limited extent; under the pressure of war conditions, however, American inventive skill found ways of performing mechanically almost all the operations that had formerly been done by hand. The McKay sewing machine, one of the greatest of our inventions, which was perfected in the second year of the war, did as much perhaps as any single device to keep our soldiers well shod and comfortable. The necessity of feeding these same armies created our great packing plants. Though McCormick had invented his reaper several years before the war, the new agricultural machinery had made no great headway. Without this machinery, however, our Western farmers could never have harvested the gigantic crops which not only fed our soldiers but laid the basis of our economic prosperity. Thus the War directly established one of the greatest, and certainly one of the most romantic, of our industries--that of agricultural machinery.