On the main line there are five tunnels, viz. one 13D yards at Armitage ; one 2383 yards upon the summit through Harecastle Hill; one on the north bank of the river wea‘er 570 yards ; Suttersford tunnel 330 yards : Preston 1E11 tunnel 1241 yards ; Harecastle tunnel is nnly 9 feet wide, and 12 feet high; all the others are 13 feet wide, and 17 feet high. In Rudyard Vale, above Leek, there is a reservoir of 160 acres, with a head 30 feet high ; near the summit there are four other small reservoirs, in all about 60 acres. The canal was begun in 1766, and the main line opened in 1777.
Besides the raw materials and manufactured goods connected with the numerous potteries, and the supplies of merchandise, the thorough trade of this canal is so extensive and various that it cannot be specified. The acts are 6, 10, 15, 16,23,25, 37, 42 Geo. III. The en gineers employed were, James Brindley, John Smeaton, Hugh Henshall, and John Rennie.
From Stoke a branch proceeds, in a veiy circuitous manner, past the WW1) of Newcastle, and thence to the Apdale and Partridge collieries : the whole is only about 8 miles in length. It consists of three separate proper ties under separate acts. Beginning at Stoke, the first three miles reaching the town is named the Newcastle under-Line canal. Its act is 35 Geo. III. Next is the Newcastle-under-Line junction, which comprehends a short piece at either end of the remainder, by act 38 Geo. III. Lastly, Sir Nigel Gresley's canal, which occupies the middle space between the two last mentioned por tions, under act 15 Geo. III. The purposes of these united canals are,to convey the Updale and Partridge coals from the westward, and the Caldon lime from the eastward.
The line of navigable communication between the me tropolis and the central parts of the kingdom, was for merly accomplished by the river Thames to Oxford, and of late years extended by means of the Oxford ca nal to Coventry. I3ut the city of Oxford lies consider ably to the westward of a straight line from London, and the crooked course of the Thames, together with its very imperfect navigation, suggested the idea of an ar tificial canal from the vicinity of Daventry ; but having to cross the intervening ridges and rallies, obstacles of no common magnitude embarrassed the project. Vet these have been all surmounted, and the extensive in tercourse now carried on fully justifies the scheme, which obtained the appropriate natne of the Grand Junc tion Canal.
The earliest promoter of this canal, we have been in formed, was William Praed, Esq. who having prevailed on the Marquis of Buckingham to patronize the project, an act of Parliament was obtained early in 1793. The general direction of the canal is north-west, through the counties of Middlesex, HertfOrd, Buckingham, Bedford, and Northampton ; and the main line is 95 miles in length. It commences in the Thames at Brentford, from which it proceeds to the valley of the Colne, Cowley, and continues to follow it past Uxbridge, Rick mansworth, Walford, King's Langley, Two Waters, Berkhampstead, to COW Roast, being 35 miles 2 furl. 8 ch. with a rise of 395 feet, and through an almost con tinued succession of mill pools. 'Die summit level is only 3i miles in length, and mostly in deep cutting.
From the northern extremity of the summit the ca nal passes hy Alarswath, near to Leighton Buzzard and Fenny Stratford to the Ouse at Wolverston, near Stoney Stratford, a distance of 25 miles 1 furl. 6 ch. with a fall of 192 feet. It here crosses the Ouse and valley by an embankment about half a mile in length, and 30 feet high, with a small iron aqueduct. From ;,thence the canal passes along the western side of the Five Rivers, and having crossed it, arrives at Stoke Bruern, being a distance of six miles 4 furl. 4 ch. with a rise or 112 feet. It here passes through Blisworth tunnel, which is 3080 yards in length, 18 feet high, and 16 feet 6 inches wide, and proceeds by IVestern Beck to the south end of Whitton Parish, in all 13 miles 3 furl. 6 chains, on one level. It then passes to Whitton Mill, a distance of 5 furl. 5 ch. with a rise of 60 feet ; from that place is a level of 4 miles 2 furlongs to the farther end of Braun ston tunnel, which is 2045 yards in length, and of the same height ancl width as that at Blisworth. From the western end of the tunnel to the junction with the Ox ford canal is 7 furl. 3 ch. with a fall of 37 feet.
Half way between Brentford and Uxbridge, at about S4 feet above the level of thc Thames, a branch pro ceeds upon one level 13a miles to Paddington, where it terminates in an extensive basin, where numerous ware houses have been erected, to accommodate a great por tion of the trade between London and the interior of the country.