1516

THEORY AMD PRACTICE OF ENGINEERING.

Book II.

Figs. 2772. and 2773. re-present a pier of the bridgeof Toledo, at Madrid , whichis in this latter style; thebase of the starlings is asemicircle.

Quay Walls of Bridges. —In general, when the bed ofthe river is permanent andnot liable to change, a wallA B is built on each side;the part B C unites thebreadth of the bridge with

Fig. 2772.

Fig. 2773. BRIDGE OF TOLEDO.

that of the roadway, which is usually more considerable: the parapet of the bridgeshould be continued round this part. AC supports the earth at the abutments; the

Fig. 2775-

PLAN,

QUAY-WALLS AT THE BRIDGE