Bumping-posts and Car-stops.—Bumping-posts or car-buffers are placed at the ends of stub tracks to stop cars which, through error in judgment of trainmen or defective brakes, would run off the end of the track. The object of the device is to effectually stop cars which strike it, and to do so in such a manner as to do the least injury to car and contents and adjacent property. The heavy, high-capacity passenger- and freightcars of the present require the use of very strong bumping-posts. Broadly speaking, bumpers arc of two kinds: (a) those which themselves absorb most of the shock, and (b) those in which most of the shock is absorbed by the train. The first class includes hydraulic bumpers, used on European railways, spring bumpers, and tracks, and a pile of dirt or sand at the end of the track. To the second class belong the great variety of rigid bumpers in use on American railways. The hydraulic bumper consists of a frame carrying a hydraulic cylinder with a longstroke piston. This acts as a dash-pot when a car strikes it. The old-fashioned pile of dirt is one of the most effective car-stops but is unsightly and requires considerable space. Rigid bumpers are constructed of wood, metal, or concrete. In some types a shoe resting on the rail engages the wheel, or the ends of the rails may be bent up to do the same thing. In most cases the bumper is anchored to the track in front and is braced from the rear. A bumper consisting of a cluster of piles bolted together has given good service on several railways. An earth buffer should be not less than 3 ft. high, about 12 by 12 ft. square and the slopes should be not steeper than 1-1/2 to 1.