justalurker66 wrote:
I assume the "inbound even" numbering that Metra uses on all of their lines predates Metra itself. I also note that an even numbered NICTD westbound passes even numbered intermediate signals and an odd numbered NICTD eastbound passes odd numbered intermediate signals.
While there are exceptions, typically on US railroads, westbound and southbound trains are odd and eastbound and northbound trains are even. UP (at least the ex-C&NW) is an exception with the timetable north-south Metra/UP-North and Northwest lines being even southbound.
I would assume CSS&SB went opposite with odd/even to match north/south IC (similarly, D&H went opposite with their north/south Albany to Montreal trains to match NYC (a NYC to Montreal train was westbound on NYC and northbound on D&H)).
While this is moving away from Chicago, Amtrak's Coast Starlight is 11/14 because 12/13 are used internally as the train changes from westbound to eastbound at Oakland in both directions (SP was eastbound in all directions from Oakland - the last I knew, 12/13 were the employee TT numbers for Oakland to/from L.A.).
Some, but not all railroads, extended the odd/even to track numbers with the innermost westbound track being track 1, the innermost eastbound track 2, then the next westbound 3, etc. With such a system, a 6-track railroad from north to south would be 5-3-1-2-4-6. Others just number consecutively from a designated side (and then there was PRR which at spots had track 0, track A, and track B, as well, I'm sure other unusual designations).