Nice that you can still get copies of the book. I have an original, but it is stored away with most of my railroad books, rulebooks, timetables, etc., up near Seattle.
On the G.O. for no signals, I'd have to point out that that only works where all freight trains are extras. If you have Second or Third Class trains out there, also, there's no way to identify who is who. For example. on my old home road, the Illinois Central: our very busy double and triple track mainline from Chicago to New Orleans had timetable special instructions stating that extras would not require white signals. We had many First Class passenger trains, but all freights were extras. No train orders were required, as the instructions also specified that a clearance card would authorize and extra on those districts.
However, on the busy single track line from Gilman, Illinois to St. Louis, extras had to carry white signals as we also had a number of Second Class schedules on the time card. Without the display of the white signals, you couldn't tell auto parts train 63 from an Extra South.
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