Chap. VIII.
BRITAIN.
577
surveys and levels were taken by the Messrs. Grundy, engineers, for the purpose of improvingthe drainage of the low lands consisting of 100,000 acres, and rendering the transit of vesselsmore convenient; nothing, however, was done until some years afterwards, when JohnGrundy, the son, Mr. Langley Edwards, and Mr. John Smeaton , were called upon to makea report upon the state of the drainage, See. In 1761 they surveyed it carefully, and foundthe river had so great a tendency to silt up, that they imagined in twenty years therewould be no drainage at all. They therefore advised the formation of another river, ofsufficient depth or capacity to drain all the neighbouring fens and low grounds, and whichshould also serve to restore the lost navigation from the sea to Lincoln. It was decidedthat the river should be cut in the shortest direction possible consistent with the lowestsurface, so that it might act as an effectual drain; that its dimensions should be sufficientlylarge to receive and discharge all the upland waters, branch rivers, and drains; that itsbanks should be strong and high enough to confine any flood waters within them, andforce them down to sea without overflowing the fens; that the bottom should be madewith a declivity from Lincoln to the sea at 5.^ inches per mile; that all the living watersshould be collected, in order to obtain a reflowing force capable of driving out any de-posits left by the tides, by which means the outfall might be preserved open and clean ;that the tides should not be suffered to flow into this new river, so that its depth anddimensions might be preserved. A lock, with two pair of doors pointing to landward for thepurposes of navigation, and one pair pointing to seaward to keep out the tides, was provided.
Ulverstone Canal commences in Morecombe Bay at Hammerside Hill, and terminates atUiverstonc. At its entrance is a sea lock 112 feet long.
Harwich and Birmingham Canal commences at Saltisford, and unites with the DigbethBranch of the Birmingham Canal near Birmingham . At Hatton is a rise of 146 feet bytwenty locks. At Knowles Wharf there is a rise of 42 feet by seven locks; and at theDigbeth Branch is a fall of 42 feet by five locks. At Haseley there is a tunnel 300 yardsin length, and another at Ilowington. It crosses the Blythe River, the Cole, and the Reaby three aqueducts.
Harwich and Napton Canal proceeds from the Warwick and Birmingham in the parishof Budbrook, and terminates at its junction with the Oxford Canal near Napton-on-the-Hill. It crosses the Avon three times by aqueducts, viz. near Warwick Bridge, Radford,and Long Itchington.
Wey and Arun Junction Canal unites the Wey near Shalford Powder Mills with theArun at New Bridge.
Wilts and Berks Canal begins at Abingdon on the Thames , and unites at Leamingtonwith the Kennet and Avon Canal. The branch to Wantage is ^ mile in length ; theLongcot Branch ^ mile, to Colne 3 miles 1 furlong, and that to Chippenham 2 miles.Where the canals lock into the Thames , it is 180 feet above the level of the sea.
River Weaver Navigation _This river has its rise in the south-west part of Cheshire ,
and, after a circuitous course, falls into the Mersey at Runcorn , about 50 miles aboveLiverpool . From the western tide-lock on the Mersey to Winsford the distance is 24miles, and the rise 52 feet only. There are 10 locks, each 80 feet in length, and 18 inbreadth, and the vessels employed on this canal are from 60 to 70 feet in length, and 17 feetin breadth, drawing from 5 feet 6 inches to 6 feet 6 inches water, when loaded with about70 tons. These works were all executed according to the conditions of an act passed inthe year 1734.
In the year 1807, another act was obtained, and Mr. Telford employed to make a canalfrom near Frodsham Bridge tothe Mersey at Weston Point,below Runcorn , a distance of 3miles 6 furlongs.
'Hie works which he executedwere the protecting piers atWeston Point, a sea-wall aboutH mile in length, two river weirsat Winnington and Saltersford,and reconstructing the locks atWetton Brook, near Northwick.
Piers at Weston Point were constructed with the sandstone of the neighbourhood, and bytheir formation the entrance into the basin was extended, affording greater facility to
rig. 556. SECTION OP WEIR AT SALTERSFORD.
vessels, both for entering and departing, than when the entrance was at a considerable dis-tance from low water-mark. The cost of these protecting piers was 78357.
Sea Batik . — For 2000 yards the canal skirts a steep bank exposed to the south-westerngales, from a reach of upwards of ten miles of sea ; and the original bank which pro-tected the canal had its upper slope paved with rubble stone, pitched on edge withoutmortar ; the waves worked into this, and softened the marl which formed the banks of thecanal, causing the rubble paving to sink into it.
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