As shown here, the train will be running in three “sections” from New York to Chicago in the scheduled 16 hours.
To save time, the fuel ‘tenders’ are replenished with water on the fly. To do this a scoop is lowered by each fireman at particular locations into very long water troughs between the rails as the locomotives operate at reduced speed. It is rather important to raise the scoop before the hard end of the trough is reached.
According to the rulebook and employee timetable, everything you see is treated as one train … for example when meeting or overtaking other trains such as slow freight trains which must get off the main track in advance of the 20th Century’s scheduled time. Any number of sections following each other at a safe distance can comprise “the train”.
The simpler the rules, the fewer trainwrecks you have …
Two locomotives here are displaying green flags indicating that a final section is still to follow - so don’t leave the siding ! When the locomotive at the left rolls by displaying no flags … today’s 20th Century Limited has passed in all its glory … and all the lesser trains in the passing tracks may resume their work on the main line.