To do all this requires a large plant, both in buildings and machinery. It is distributed at every important point along the railroad. At terminal and operating points, roundhouse facilities of greater or less extent are sure to be located, and at the headquarters of each division these are generally expanded into shops for the making of light repairs and to avoid handling crippled equipment for any great distance. One large shop plant is apt to suffice the average railroad for the heavy repair work. If the road stretch to any extraordinary length, even this feature is apt to be duplicated in order to concentrate this repair work as far as possible. All this concerns the care and repair of the locomotive--which the railroader quickly groups under the title "motive-power." To care for the engines while they are in use out upon the line, to see to it that engineers and firemen alike handle these mechanisms with economy and skill, is a responsibility that is placed upon the road foreman of engines of each division. He has supervision over smaller roundhouses but at any of the larger of these structures there is a roundhouse foreman in direct charge. The railroad long ago learned that its best economy rested in having plenty of executive control. That has come to be one of the maxims of the business. There is a master mechanic in charge of the division shops and in many cases he has authority over the road foreman of engines and the roundhouse foremen. Then under him he has his various assistants, forming a working force not at all unlike that of the average iron-working shop. All this organism is gathered together under a superintendent of motive power, who in turn may report to a general mechanical superintendent. This official answers only to the general manager, or, in some cases, to a vice-president to whom these functions of the care of the railroad are delegated. The proposition of the cars is generally treated quite apart from that of the locomotive, and separate shops under the direction of a master car-builder and his assistants are located at a few points upon the system, where they may be of fairly easy access. Rough repairs (the car-builders term these "light" repairs) to cars are carried forth at each division yard. This work is almost entirely confined to the freight equipment, and a good part of it goes upon "foreign" cars--cars that do not belong at all to the railroad making the repairs.