The MERR was very advanced for its time; making extensive use of automation in operating the railroad. A fascinating component of this automation scheme was the idea of a 'push-pull' coal train; the only such implementation as far as my research has shown. A few hopper cars were equipped with a headlight, bell, multi-chime horn, and electrical automation components. The headlight and horn can be seen on MERR hopper #6 above. The whole system was well-designed and functioned quite well, and is my favorite railroading operation. A Bruce van Sant original Kodachrome slide from my collection.