good portions of rejected timbers; but in doing so great care should be exercised to prevent the workmen from putting any poor material into the work. The fact that all the timber received had been previously accepted by the timber inspector is no reason for using unsatisfactory material; moreover, sometimes it happens that timbers which the inspector has never even seen are marked with his stamp and shipped.

Second. See that the floor system is properly laid and attached to the metal-work, that each rail bears effectively upon every tie which it crosses, and that the rails are laid straight, evenly, and to exact grade.

Third. See that the hand-railing is brought to proper alignment, and is held there in a permanent manner.

Fourth. See that all joists in highway bridges are properly dapped on floor-beams so its to bring all of their upper surfaces to exact elevation or elevations; also, that all intermediate joists lap past each other far enough to reach entirely across the top flanges of the floor-beams. See that the outer lines of joists abut and run continuously, and that they are effectively spliced on the inside.

Fifth. See that all joists in which the depth exceeds four times the thickness are bridged at distances not to exceed eight feet, and that when the hand-railing depends for its rigidity upon that of the outer joists the latter are well bridged and otherwise stiffened where the posts are attached.

Sixth. See that alternate bolts attaching guard-rails to floor pass through both the flooring and the outer joists, and that all holes through the latter are bored in the central plane of the joist.

(J) MASONRY.

First. Inspect all stone as soon as received, so as to see that it has not been injured in transit, and that it is satisfactory in every particular, even if it has already been passed by the stone inspector.

Second. See that all stones are thoroughly cleaned and wet before being laid.

Third. See that all mortar is mixed in the proper propor-