Then the method generally adopted at first for destroying a railway track was to tear up sleepers and rails, place the sleepers in a heap, put the rails cross-ways over them, set fire to the sleepers, and heat the rails until they either fell out of shape or could be twisted around a tree with the help of chains and horses. But this process was found to require too much time and labour, while the results were not always satisfactory, since rails only slightly bent could be restored to their original shape, and made ready for use again, in much less time than it had taken for the fire to heat and bend them. A Federal expert accordingly invented an ingenious contrivance, in the form of iron U-shaped "claws," which, being turned up and over at each extremity, were inserted underneath each end of a rail, on opposite sides, and operated, with the help of a long wooden lever and rope, by half a dozen men. In this way a rail could be torn from the sleepers and not only bent but given such a spiral or corkscrew twist, while still in the cold state, that it could not be used again until it had gone through the rolling mills. By the adoption of this method, 440 men could destroy one mile of track in an hour, or 2,200 men could, in the same time, destroy five miles. The most effective method for rendering a locomotive unfit for service was found to be the firing of a cannon ball through the boiler. Carriages and wagons which might otherwise be used by the enemy, and could not be conveniently carried off, were easily destroyed by fire. In one period of six months the Federals disposed of 400 in this way. Stations, water-tanks, sleepers, fuel and telegraph poles were also destroyed or rendered useless by fire or otherwise. In the first year of the war--1861--the Confederates gave the Federals a foretaste of much that was to come by destroying forty-eight locomotives on the Baltimore and Ohio Railroad, and making a complete wreck of 100 miles of the North Missouri Railroad track and everything thereon. Much more serious than this, however, from a strategical point of view, was the wholesale destruction carried out by the Confederates, in April, 1862, on the Fredericksburg Railway, connecting Richmond and Washington, the immediate result of the mischief done being to prevent an impending combination between the Federal armies of the Potomac and the Rappahannock, neither of which could act without the other, while neither could join the other unless it could make use of rail communication. There was much that required to be done, for the Confederates had carried out their work in a most thorough-going fashion. Several indispensable railway bridges had been destroyed; three miles of track had been torn up, the rails being carried south and the sleepers burned; and wharves and buildings had been burned or wrecked. The whole transportation service, in fact, had been reduced to a state of chaos.