International Correspondence Schools · Scranton, Pa. : The Colliery engineer co. · leaf 348
ned in such localities. Substantialmonuments should be set at each of the principal points. Ashort section of log, cut ofif square, or a section of Sawed tim-ber of equal length, set on end in a pit and bedded in cementmortar rubble, answers this purpose well. The timber shouldextend three inches… … manent target, which is set up at each of the principal points.A monument corresponding with the above description isshown in Fig. 424, and target in Fig. 425. The target is made of pine or spruce. The shank whichfits the hole in the monument and the target are of onepiece. The surface of the…
Railroad engineering
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