International Correspondence Schools · Scranton, Pa. : The Colliery engineer co. · leaf 368
F. The roof timbers G, H, K are clamped together as in Fig. RAILROAD CONSTRUCTION. 957 450, and mortised into the cap at spring line. The pressureagainst the roof timbers is reHeved by the struts /,, J/, A, H,and [, which transfer the stress to the posts C and D andthe cap E F. The dimensions of… … FlG. 451. ting in half straight grained chestnut or oak saplings. Thebacking may be either dry rubble or cordwood. The latteris preferable, as it is light, portable, and uniform in shape.The side walls are all of well-scabbled rubble of good-sizedstones, even beds, and laid in courses with cement…
Railroad engineering
Internet Archive · California Digital Library · Public Domain Mark 1.0. Free to use for anything.
