A manual of the principles and practice of road-making: comprising the location, construction, and improvement of roads, (common, macadam, paved, plank, etc.) and rail-roads. By W. M. Gillespie ...

SIGNALS. 333
and in addition, when any emergency reqjires the immediate and certain stoppage of any train, a detonating compound, packed in a small box, is fastened to the rail with
slips of lead, and explodes with a tremendous noise when a
wheel passes over it, giving an unmistakeable signal for
instant stoppage.
White and red lights on the front and back of a train
at night should be so arranged and combined as to indicate the direction, speed, &c. of the train. But all these
precautions are finally dependent for their complete success upon the character of the persons in the employ of
the company.
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