"Three trucks, each drawn by two horsus, ply between the track layers and their supplies. The horses run outside the track, pulling with a long tow line, as boats are moved on canals. They must be out of the way of the workmen. One of these trucks takes on a load of rails, about forty, with the proper proportion of spikes and chairs, making a load, when tiie horses are started on a full galop for the track layers. On each side of these trucks are rollers to facilitate running off the iron. On reaching the end of the last rail, the truck is stopped. A single horse is attached to move it over each successive rail. Meanwhile the truck last emptied has been turned on its side to allow the loaded one to go to the front. The horses released aro started back on a keen gallop for another supply. Tho third ono moves up in like manner, and thus through all the day they aro rushing for ward with their iron load. To sco them, and reflect what their rush and roaring moans,.is as exciting as it i-ver was to watch a battery thunder into position at a needed moment at the vital point in its line. "Tiie rails within reach, parties of five men stand on cither side. One in the rear throws the rail upon •the. rollers, three in advance seize it, and run out with it to the proper distance. The chairs have, meanwhile, baen sot under the last rails placed. The two men in tho rear with a single swing force tho end of the rail into the chair, and the chief of the squad calls out * down,' in a tone that equals the ' forward ' fro an army. Every thirty seconds there camo that brave ' down,' ' down,' on either side the trr.«.k. They -.rcro th<: pendulum beats of a mighty er.-v ; they marked tho time of the march, and its regulation step.
