International Correspondence Schools · Scranton, Pa. : The Colliery engineer co. · leaf 612
^N, … Fig. 610. elevation. This is the sim-plest and easiest method ofelevating the outer rail of atrestle. There are no shimsto get out of place or need -s^i^^renewing, and there is no ^increase in cost above thatof a trestle on a straight line. In Fig. 609 the outer rail is elevated by means of a shim…
Railroad engineering
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