The third part of the canal of Picardy consists in joining the Somme to the Scheldt, between St. Quintin and Carnbray, continuing along the Scheldt. by Crevecoeur, Carnbray, and Bouchain, to Valenciennes, where the Scheldt is navigable. In 1766 NI. Laurent thought a canal could he made for twenty millions of livres, and judged it practicable to make a communication by a tunnel, which should be seven miles long ; and this plan was commenced. The head of thc canal was fixed at the village of St. Simon in Vermandois, near St. Quintin ; beyond that it extends towards Couchant, and enters thc mountain four miles Irom St. Quintin, to proceed to the Scheldt at Vendhuille, distant seven miles, and 10 from Carobt ay, in a straight line. In 1767 the plan was ap proved, and in February 1768 the work was begun, viz. the earth work or excavation fi on) Vendhuille to Benthall, and front Trongusy to St. Quintin, and the entries of the tunnel. In February 1769, NI. Laurent was appointed director-general of these vvorks, likewise to render the Scheldt navigable to Valenciennes ; but the expenses of the state interrupted the payments. In 1772 and 1773 funds were procured, and considerable progress made, with opening wells, drains, Ste. and constructing a part of the tunnel. They proceeded carrying forward the tunnel towards Trongay, as they had in 1768 proceeded from it. The breadth of the waterway was to be 17 fect, besides a brenching on each side of two 2 feet 11 inches, making 21 feet 3 inches, and 21 feet 4 inches in height, from the bottom of the canal to the crown of the arch; the dcpth of the water to be 5 feet 4 inches.
In 1773, objections were raised against this line of canal and tunnel. ln the mean time, NI. D'Alembert, the Abbe Bossut, and NI. Condorcet, having bcen ap pointed directors of Inland Navigation, thought proper to have the matter thoroughly examined. In 1775, NI. Trudaine gave notice, that the tunnel operations would be suspended. In 1800, the first consul (Bonaparte) personally examined this tunnel, and ordered a fresh in spection of it by the engineers of roads and bridges. The report was referred to the Institute, who decided in favour of the ancient plan of Devic, and an arra in 1801 confirmed this decision—that is, that the canal should proceed by Omini, Le Tronquoi, Bellinglise, Riqueval, and Maquincourt, and in that direction it has been com pleted in 1810. The length of the canal is 32 miles 1151 yards. It is fed by the Somme and the Scheldt, from St. Quintin to the point of partition—From the junction of the canal Crozat to the lock of Tronquoi, at one end of the summit, the rise is 33 feet 6 inches by five locks. The summit is 13 miles 435 yards, includ ing two tunnels, viz. Tronquoi 1191 yards, and that of Riqueval, 3 miles 1026 yards. These tunnels are 26 feet 3 inches in width. From this end of the tunnel to Cambray is 15 miles 694 yards, with a fall ef 123 feet 6 inches by 17 locks, each of which is 97 feet long and 17 broad.
From this northern extremity of the kingdom we shall now pass to that district situated between the Seine and the Loire, where the first important project for inland navigation in France was executed, that is, the canal of Briare, begun in 1605 under Henry IV. The en gineer
was Hugues Crornier. Operations were suspended in 1610. In 1639 the works were resumed, and pi °scented until they were completed in 1642. It is .34,1 miles in length. It commences in the Loire, a mile from Briare; ascends by Ouzonne, along the banks of the river Trezee, by Rogny, where there are seven locks. Thence it pro ceeds by Chatillon and Nlontargis, and near Cepay joins the river Loing, which falls into the Seine. Thc locks of this canal are the first which were executed in France ; they are supplied with water front several lakes, between Chatillon and Briare, on the side of Rogny. There is only one feeder, which has proved insufficient ; for boats drawing only 2A- to 3 feet water have frequently to be lightened. The breadth of the canal is unequal, being from 25 to 32 feet at tile surface. The locks are from 124 to 164%; feet long, 14 feet 5 inches in breadth ; and vary in risc from 5 feet 4 inches to 13 fcct 8 inches.
Feet. In.
From the Loire to the summit, the distance is 9 miles, the rise 126 4 The summit level is . . 31 do.
From summit leNel to Loing at Montargis,24—the fall 259 34,1 The feeder of St. Prive, in a distance of 12 miles, has a fall of five feet only. The boats are drawn each by two men. The navigation is every year interrupted, not only by the repairs, but the shallows of the Loire, and that not unfrequently for three months. Each canal-boat carries from 100 to 115 milliard, and draws from 28 to 30 inches of water. There are 25 lock-keepers, one general guard, and 11 others to watch the canal, lakes, and feeders. The lock-keepers, Stc. are chosen from masons, carpenters, and earthworkers.
The canal of Orleans originated from the imperfec tions of the canal of Briare, and tlie difficulty of ascend ing the Loire 36 miles above Orleans to reach it. In 1680 an arrt was registered to permit a canal to be made from the Loirc, a little below Orleans, to the river Loing, below Montargis. The work was begun in 1682, and prosecuted until 1684. It was then stopped in 1688. The house of Orleans, who had originally proposed the canal, now re-entered,upon paying the company a rent of 15,000 livres. The canal is supplied from numerous lakes by feeders, one of which, Courpalet, is 194 miles long, and, according to Regimorte, has only a fall of four feet. The total length of thc canal is 45 miles. It has locks, varying from 1361 to 1774, feet in length, and from 5 feet 4 inches to 12 feet 7 inches in rise. From the Loire to the summit, the rise is 98 feet 2 inches; from the summit to the Loing, the fall is 137 feet 7 inches. The breadth of the canal is generally from 25 feet 7 inches to 32 feet at the surface of the water. The depth is CI feet, whcn full, to 2 feet when lowest. The boats are from 96 to 1021 feet in length, and 13 feet 10 inches in breadth. It is said that this canal has been much neglected. Regimorte made many repairs in 1725 and '726.