double-track bridges there will be required two such angles per panel between inner stringers, and four diagonal angles per panel to run from where the lateral diagonals intersect the outer stringers to where the inner stringers meet the cross-girders.

All plates, angles, and channels used in built members of trusses must, if practicable, be ordered the full length of the member; otherwise the splices must develop the full strength of the member, without any reliance being placed on the abutting ends for carrying compression.

But in total splices at the ends of sections perfect abutting of the dressed ends is to be relied upon. However, the splice-plates even there must be of ample size and strength for both rigidity and continuity.

The unsupported width of plates strained in compression, measuring between centre lines of rivets, shall not exceed thirty-two (32) times their thickness, except in the case of cover-plates for top chords and inclined end posts, where the limit may be increased to forty (40) times the thickness. Where webs are built of two or more thicknesses of plate, the rivets that are used solely for making the several thicknesses act as one plate shall in no case be spaced more than twelve (12) inches from each other or from other rivets connecting said component thicknesses together. The least allowable thickness for such compound web-plates shall be one (1) inch.

The open sides of all compression-members composed of two rolled or built channels, with or without a cover-plate, shall be stayed by tie plates at ends and by diagonal lacing-bars or lacing-angles at intermediate points. Lacing-bars may be connected to the flanges by either one or two rivets at each end; but lacing-angles, which are used for members of heavy section only, must be connected by two rivets at each end.

The tie-plates shall be placed as close as practicable to the ends of the compression-members. Their thickness shall not be less than one-fiftieth (1/50) of the distance between the centre lines of the rivets by which they are connected to the flanges, unless said tie-plates be well stiffened by angles, in which case they  may  be made as thin as three eighths (3/8) of an inch.