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 Fig. 61. Operation of Freight Car-Floats at a Railroad and Steamship Freight Terminal

Here we have time represented by days in the horizontal direction and by hours in the vertical direction. The object of the chart is to record whether car-floats are loaded and dispatched at the same hour each day.

Dotted lines show the time at which cars are pushed onto car-floats by locomotives. Solid lines show the time at which car-floats are towed away by tug-boats. Curves for any one car-float destination are in pairs bearing the same letter.

If the departure schedule is well maintained, all curve lines will be practically horizontal. Note that the blizzard of January 7 affected the locomotives less than the tug-boats