Chap. XXIII.
SWING BRIDGES.
1387
extends over the abutments to a sufficient distance to counterpoise its weight over thecanal a pivot, or small wheel, enables it to be turned readily. Swing bridges may be
Fig. 2295.
constructed on the suspension principle, and made to revolve on rollers working ii
ffronve nr irrm rail • of * 1 .^.. -_ _i_ i • , • , . . ® _
. • ■ - t- ziy ~. -- - : a.
SWING BRIDGE.
Fig. 2298.
HAVRE SWING BRIDGE.