In 1947, New York Central was running 14 trains a day each way between New York City and Chicago. By the time of this timetable, two years later, that number had dropped to eight.
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In fact, the number was really only seven. The Pacemaker and all-Pullman Advance Commodore Vanderbilt are listed as two separate trains, but as of the January 30, 1949 timetable, the two trains were combined and the schedules show the exact same times for both.
The equipment listings say the Pacemaker included a lounge car, “dining service,” and an observation-buffet-lounge car while the Advance Commodore had a lounge-sleeping car (six bedrooms plus a buffet-lounge) and dining service. I suspect this meant the sleeping cars were at the front of the train, separated from the coaches by a twin-unit diner. Sleeping car passengers could go back to the observation car if they wanted to but coach passengers could not go to the lounge-sleeper. In addition to the lounge-sleeper, the train carried at least six other sleeping cars, two of which were probably heavyweights.