560

HISTORY OF ENGINEERING

Book I.

from the Staffordshire into the Birmingham and Liverpool Junction, brings with it a lock-full of water, and as this is received into the summit level, it serves throughout the whole

SIDE OP AQCEDl'CT.

passage to the Mersey. To provide for evaporation, there is a reservoir of fifty acres atBelvide, and another of the same size at Knighton; these two reservoirs are shallow, butthey will allow a foot in depth to be drawn off, if required for lockage water.

IHMItllflll

IHIUImi;ii|

PLAN AND SECTION OF LOCK.

The Cheshire marl used for the embankments stood very well where the height did notexceed 10 or 12 feet, but was found hazardous beyond that, not retaining its shape, andslips and bulges occurring to a great extent.

Blyth River rises near Laxfield, and terminates at Southwold in Suffolk .

Borrowstounness Canal proceeds along the south side of the Firth of Forth , and uniteswith the Forth and Clyde canal near the mouth of the Carron rivers.

Bradford Canal commences near Shipley, and terminates at Iloppy Bridge.

Brecknock and Abergavenny Canal commences near Pontypool ; it crosses the Avon byan aqueduct, and then, by a tunnel 220 yards in length, it proceeds to Abergavenny andBrecon.

Bridgewater Canal (the Duke’s) extends from Worsley to Manchester . From Castlefieldit proceeds to Longford Bridge, a distance of miles ; 18£ miles further it joins the Trentand Mersey, and at miles arrives at Runcorn ; it then falls into the Mersey by ten locks,which are together 82 feet 6 inches.

The Worsley branch is 5 miles, and from thence to Leigh 6 miles. This canal, executedat the expense of the Duke of Bridgewater, who has been justly called the father of British inland navigation, is on one level the greatest part of its length: this is done by means oflofty and wide embankments ; one of these, over Stretford meadows, is at the base 112 feetwide, and 17 feet high ; the Barton aqueduct, which is 89 feet above the Mersey and Irwellnavigation, is 200 yards in length.