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

In panel No. 5, it will be 16 feet.

and applying the formula

2240bd³
L² = W

we get, in round numbers, the following dimensions, the braces being bolted and blocked together:—

For the 1st panel, 25 feet long, 8 × 10

For the 2d panel, 37 feet long, 8 × 10

For the 3d panel, 49 feet long, 8 × 10

For the 4th panel, 64 feet long, 8 × 10

For the 5th panel, 78 feet long, 8 × 10.

For the lattice-work, a double course on each side of each truss, in long spans, (150 to 200 feet); and a single course in shorter spans, of 3 × 6 plank, treenailed at intersections, is ample.