Breakage of machinery is more liable to take place while wheels are revolving 25,000 times per hour, than when the speed is less.
Failure of the superstructure of bridges, (particularly when on curves or grades,) is more liable to take place at high than at low velocities.
Accidents from obstacles upon the track, from fire, boiler explosions, and misplaced switches, are no more attendant upon express than upon other trains, but the consequences are worse with the high speeds.
From the analysis above, of one hundred accidents, it appears that eighty-eight per cent. of the cases are due to the causes that are aggravated by increase of speed, and if we assume the aggravation of collision, and breakage of machinery, to be (speed being doubled) as two to one, the danger of travelling a fixed distance, by express, is eighty-eight per cent. greater than by a slow train.
COMPARATIVE COST OF WORKING HEAVY AND LIGHT TRAINS.
414. The question is sometimes asked, if it would not be better to run a greater number of trains and reduce the weight of engines. A comparison of cost is easily made.
The cost of working trains consists of
Fuel, oil, and waste.
Engine-men’s wages.
Wear of rails.