A Treatise On The Principles And Practice Of Dock Engineering

430 DOCK ENGINEERING. (6) A short, stout pivot with a hemispherical head, as in fig. 407, taken from a bridge at Liverpool. This type naturally offers great resistance to Fig. 406. — Bridge Pivot at Rotterdam. Fig. 407. — Bridge Pivot. K\\\W NW Fig. 408. —Raritan Bridge Pivot. pressure and concussions, and affords a broad base for the distribution of stress. It allows of the bridge tilting slightly, but any decided movement in this direction may be checked by a ring of rollers, or by wheels at suitable points. In some instances a more pointed bearing surface will be found, as in fig. 408, showing the arrangement in the Raritan bridge. The rollers are here called upon to exercise considerable steadying effort. (c) A long, cylindrical pivot with a concave seating or bearing—strictly speaking, a socket—as in fig. 409, exemplified in several forms. In one case, at Hawarden