After supper, they gathered on the front porch, and sat looking down over the busy, noisy yards. The switch-lamps gleamed in long rows, red and green and white, telling which tracks were open and which closed. The yard-engines ran fussily up and down, shifting the freight-cars back and forth, and arranging them in trains to be sent east or west. Over by the roundhouse, engines were being run in on the big turntable and from there into the stalls, where they would be furbished up and overhauled for the next trip. Others were being brought out, tanks filled with water, and tenders heaped high with coal, ready for the run to Parkersburg or Cincinnati. They seemed almost human in their impatience to be off—breathing deeply in loud pants, the steam now and then throwing up the safety-valve and “popping off” with a great noise. The clamour, the hurry, the rush of work, never ceasing from dawn to dawn, gave the boy a dim understanding of the importance of this great corporation which he had just begun to serve. He was only a very little cog in the vast machine, to be sure, but the smoothness of its running depended upon the little cogs no less than on the big ones. A man’s figure, indistinct in the twilight, stopped at the gate below and whistled. “There’s Reddy Magraw,” said Jack, with a laugh. “I’d forgot—it was so hot t’-day, we thought we’d go over t’ th’ river an’ take a dip t’-night. Do you know how t’ swim, Allan?” “Just a little,” answered Allan; “all I know about it was picked up in the swimming-pool at the gymnasium at Cincinnati.” “Well, it’s time y’ learned more,” said Jack. “Every boy ought t’ know how t’ swim—mebbe some day not only his own life but the lives o’ some o’ his women-folks’ll depend on him. Come along, an’ we’ll give y’ a lesson.” “I’ll be glad to!” Allan cried, and ran indoors for his hat. Reddy whistled again. “We’re comin’,” called Jack. “We won’t be gone long,” he added to his wife, as they started down the path. “All right, dear,” she answered. “An’ take good care o’ th’ boy.” Reddy greeted Allan warmly, and thoroughly agreed with Jack that it was every boy’s duty to learn how to swim. Together they started off briskly toward the river—across the yards, picking their way carefully over the maze of tracks, then along the railroad embankment which skirted the stream, and finally through a corn-field to the water’s edge. The river looked very wide and still in the semidarkness, and Allan shivered a little as he looked at it; but the feeling passed in a moment. Reddy had his clothes off first, and dived in with a splash; Jack waded in to show Allan the depth. The boy followed, with sudden exhilaration, as he felt the cool water rise about him. “This is different from a swimmin’-pool, ain’t it?” said Jack. “Indeed it is!” agreed Allan; “and a thousand times nicer!” “Now,” added Jack, “let me give you a lesson,” and he proceeded to instruct Allan in the intricacies of the broad and powerful breast stroke.