Handbook of Railroad Construction; For the use of American engineers. / Containing the necessary rules, tables, and formulæ for the location, construction, equipment, and management of railroads, as built in the United States.

by George L. Vose

Suppose rails to last ten years, the annual depreciation is ten per cent. At sixty lbs. per yard we have one hundred and five tons per mile, which, at $60 per ton, amounts to $6,300. Let the cost of rerolling and relaying be $30 per ton, the depreciation is then $30 per ton for ten years, or $3 per ton per annum, or $315 per mile per annum.

SLEEPERS.

If sleepers last seven years, and cost forty cents apiece, their annual depreciation per mile (at 2,400 per mile) will be $138 per mile (nearly).

BRIDGES.

If wooden bridges cost $30 per lineal foot, and last twenty years, the annual depreciation per foot will be $1.50, and if there is ten feet per mile of road, $15 per annum per mile.

EXTRAS.

Allowing for the annual depreciation per mile of buildings, fences, etc., $33, we have as the whole annual depreciation, $500 per mile; and the amounts which yearly reserved and placed at compound interest for each of the ten years, will pay for reproducing the road, are as follows:—

At the end of the 1st year $298

At the end of the 2d year 315

At the end of the 3d year 333