The MERCURY was an experimental streamlined train, the pride of the New York Central Railroad System, which was put into service between Cleveland and Detroit on 15 July 1936. It was a new kind of train for its day. Designed as a day train, it had completely air-conditioned cars, with curving leather divans and armchairs instead of traditional 2-by-2 seating. Colorful interiors and new and unusual lighting effects were other unique features of the train. The Mercury was developed for use by businessmen who commuted frequently between Cleveland and Detroit; its schedule was set for their convenience. It left Cleveland at 7:30 A.M. and arrived in Detroit at 10:20 A.M. The return trip departed Detroit at 5:30 P.M. The only stop either way was in Toledo.
The train started with 7 cars. On its first anniversary of service, there were 9 cars. During that first year, it had carried 112,000 passengers. The observation car in the rear had a speedometer set in the top of one of the lounges. The passengers could see the train's speed, as high as 80 mph. The Mercury gradually lost its special appeal as newer, faster trains were developed and automobiles and airplanes became the preferred mode of travel. It was used for regular runs between Cleveland and Detroit until service was phased out in July 1959.
Cook, Richard J., Sr. New York Central's Mercury: The Train of Tomorrow (1991).