3. The Wilts and Berks canal, of the 35th, 41st, and 50th George III. departs from the Kennet and Avon at Samington, passes near Milksham, Chippenham, Wot ten Basset, and \Vantage, along the foot of the Chalk Hills to Abingdon on the Thames. Its length is about 52 miles. Cuts are made from this canal to Chippen ham, t mile ; to Caine, 3 miles ; to \Vantage, 1 mile. A branch also passes to the Thames and Severn canal near Crieklade. The Wilts and Berks is calculated for boats 70 feet long, and seven feet beam. It is 27i feet wide at the surface of the water, t4 at bottom, and 4i feet deep.
The third great thoroughfare between the rivers Thames and Severn, and the first constructed, was the Thames and Severn canal, acts 23d, 31st, and 36th George III. It commences at the extremity of the Thames and Isis navigation, near Lechlade : thence to the eastern end of the Sapperton tunnel is 20i miles, in which 16 locks ascend 131 feet. This tunnel, upon the summit, is 4300 yards in length, 15 feet in width, and 250 feet below the highest part of the hill. From the western end of the tunnel to the Stroud canal, at Well bridge, near Stroud, a distance of 711 miles, the fall is 241 feet by 28 locks. The canal is 42 feet wide at the water's surface, and 28 feet at the bottom, and about five feet deep. Vessels 80 feet long and 12 feet wide, car rying 56 tons, and drawing 3 feet 6 inches of water, pass this canal and down the Thames. Robert Whitworth and Joseph Clowes were the engineers. This canal was finished in 1789.
The Stroud canal proceeds eight miles, descending 102 feet by 12 locks. To the Severn at Framiload, this canal admits seven trows of 66 feet long, 16 feet wide, and 5 feet deep, carrying 75 tons. The acts were 2d and 34th George II. and 15th, 23d, 33d, and 37L1) George III. The first attempts to make Stroudwater naviga ble, was rendered ineffectual by the resistance of the millers, and the mismanagement of a scheme for trans ferring goods from one level to another by means of cranes. The engineers were Thomas Yeomen and Ro bert Whitworth.
Having again reached the Severn, we shall next no tice the navigations on the northern shore of the Estuary. Milford haven forms an excellent harbour for vessels en tering the British Channel. It is navigable to Haver fordwest ; and near to Narberth, a tract or stone coal, and culm, extending from St. Bride's Bay to Tenby, is
thus rendered accessible. In Carmarthen Bay there are also natural navigations to St. Clares in the Towe, and to Carmarthen on the Towey.
At Kidwelly commences the great coal basin of South \Vales, extending to Swansea, Bridgend, Caer philly, and Pontypool, and northward to the boundary of Brecknockshire. The north-western seams are chiefly stone-coal ; burning without flame, they are extensively used in malting, Ste. The more southern beds are bitu minous, and extensively exported to the west of Eng land, Ireland, and France, &c. In the north-eastern parts, the coal being. farthest from the coast, has beet) chiefly wrought for smelting ironstone: inexhaustible beds of which accompany the coal strata. The quantity of iron produced in this district is nearly 200,000 tons an nually. Near Swansea, and at other places along the coast, furnaces are constructed for smelting copper ore, baking porcelain, Ste. There are also manufactures of tin plates and iron-wire, rolling-mills, Ste. These ope rations have led to the formation of various canals; and when these have been found impracticable in the hilly country, extensive rail or tram-roads, with inclined planes, have been adopted.
At Kidwelly a short canal was early formed by Mr. Keymer, from his coal works to the shipping-place, on the Kidwelly river ; since that time it has been extended by an aqueduct over the Gwendreth Vawr, to some col lieries to the eastward.
The Burry river is navigable for 10 miles to Loughor. From the dock or harbour at Llanelly, the Carmarthen shire railwhy (Act 42d George III.) extends 15 miles, through a productive coal country, to the lime works near Llandethe ; and on the eastern side are railways to the extensive coal works of General Waide.
At Swansea, the river Towe is navigable for about three miles among the copper works. The mouth of the river has been made a good ticie harbour, by piers constructed under the direction of Captain Huddart. From the town the Swansea canal proceeds along its western bank, for about 18 miles to the Henoyadd lime works. The total rise is 411 feet. Several railways com municate with this canal to the coal Ivoi ks on the other side or the valley. Act 134th George III. Engineer, Thomas Shearsley.