Chap. VIII.
565
with high water of the lowest neaps, and the other is 15 feet 6 inches higher. The depthof water in the canal is 8 feet; the locks arc 17 feet wide and 74 feet long, and the supplyis drawn from a reservoir, into which the waters of the Eden are pumped up.
Mr. Chapman showed considerable ability as an engineer in the execution of this work,and was very extensively employed till his death, which took place 29th May, 1832, in his83d year.
CkesttrJxeM Canal commences at Stoekwith in Nottinghamshire , and terminates atChesterfield. From the Trent to Worksop, a distance of 24 miles, it rises 250 feet, and inthe next 9 miles it rises 85 feet. Between the summit and Chesterfield, a distance of13 miles, the fall is 45 feet; between Wales and Ilarthill is a tunnel 2S50 yards in length,12 feet high, and 9 feet 3 inches wide.
Coventry Canal commences on Fradley Heath, and ends at Coventry ; it is joined in itscourse by the Wyrleyand Essington Canal, and by the Birmingham and Fazely. The first11 miles is level; near Tamworth there is a rise of 14 feet 6 inches by two locks; fromthence to Grendon, 6$ miles, it is level; from the latter place to Atherstone, a distance of2\ miles, there is a rise of 81 feet 6 inches ; it is afterwards level to Coventry.
Crinan Canal crosses an isthmus in Argyleshire, commencing at Ardreshaig in LochGclph, and falls into Loch Crinan near Duntroon Castle.
Cromford Canal, the engineer to which was Mr. William Jessop , commences near LangleyBridge, in the county of Northampton. The top width of the canal is 26 feet, and theboats employed upon it are 80 feet in length, 7 feet 2 inches wide, and 3 feet 4 inches deep ;when loaded with 22 tons, they draw 2\ feet of water, and when empty about 9 inches.The tunnel at Ripley is 9 feet wide at the surface of the water, and from thence to thecrown of the arch it is 8 feet high : for the construction of this tunnel, which is 2966 yardsin length, thirty-three shafts were sunk, some of which were 210 feet in depth ; the costof this work averaged 71. for each yard in length. There is an aqueduct bridge nearWigwell over the Derwent, 200 yards long, and 30 feet high, the arch over the riverhaving a span of 80 feet; near Fritchly is another aqueduct, 200 yards long and 50 feethigh, and the two cost 60004 The reservoir of 50 acres over the Ripley tunnel is 12 feetin depth, and contains 2800 locksfull of water, which is discharged by a large pipe andcock in one of the tunnel pits ; the embankment of this reservoir is 200 yards long, 156 feetwide at the base, and 12 feet wide at the top : there are two other reservoirs, one containing20 and the other 15 acres. The engineer has informed us that for cutting and wheelingthe clay, the price usually paid for a stage of 20 yards was 3 } x d. per cube yard, for gravel4 }/t., and that the entire cost of the canal was 80,0004 ; it was completed in 1793.
Dearne and Dove Catial commences near Swinton, and near Dunn passes through a shorttunnel, and terminates near Barnsley.
Derby Canal commences on the Trent, near Swarkstone, and terminates at Little Eaton ;there is a branch to Krewash (.’anal.
Dorset and Somerset Canal commences at Gains Cross, and terminates in the Kennet andAvon Canal at Wedbrook.
Droitwich Canal commences in the town of that name, and terminates at Ilawford Bridge,where the Salwarp river falls into the Severn ; this work is said to have been by Brindley,and is most admirably executed.
Dudley Canal proceeds from the Worcester and Birmingham Canal, at a place near SelbyOak, and near Stonehouse enters the Lapal tunnel, which is 3776 yards long ; beyondHales Owen is another tunnel 623 yards long, and at Dudley Woodside a third 2926 yardsin length, a short distance beyond which the canal communicates with the Birmingham .There is a branch canal two miles in length, called the Black Delph, which falls into theStourbridge Canal.
Edinburgh and Glasgow Union Canal has its commencement two miles west of Falkirk ,at the sixteenth lock of Forth and Clyde navigation. Over the Avon is an aqueduct 80feet above the surface of the river ; this canal terminates by a basin at the Lothian road; itis fed at one place by a suspension aqueduct, which crosses the Almond river.
Ellesmere and Chester Canal leaves the tideway of the Mersey at Ellesmere Port , crossesthe river Ceiriog by a stone aqueduct, and at Pont Cysyllte by an iron one, and falls intothe Montgomeryshire Canal.
The Llanymynech branch leaves at Francton common, out of which is another, whichterminates at Weston Lullingfield. The main line of the canal rises 46 feet in the first 8^miles; from Chester to the Harleston locks is 15jj miles, with arise of 131 feet, by meansof eleven locks. From these locks to Francton Common it rises 115 feet in a distance of 25miles; from Francton Common to its termination in the Montgomeryshire Canal, it is 11|miles, with a fall of 52 feet. The branch from Wardle Green to Middlewich is in length10 miles, with a fall of 44 feet 4 inches by four locks; that to Ruabon Brook Railwayis 11 miles in length, with a rise of 13 feet. The aqueduct over the Dee, at PontCysyllte, has a height of 125 feet; the pillars are 52 feet apart. The trough throughwhich the vessels pass is 320 feet long, 20 feet wide, and 6 feet deep, formed entirely of cast-
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