In descending the Seine towards Paris, there is the small liver Voulsye, which never fieezes, and here are the vestiges of an ancient canal, supposed to be made by the Romans. The demands of Paris have tendered canals desirable, but in all the projects the expense has always been found to be too much. In 1724 it was pro posed to make a canal from Paris to the river Oise, near Isle Adam, to Meny sur l'Oise; the high water of the Oise at Vaux is Si feet above high water of the Seine at Paris. But this project was rejected by the magistrates of police of Paris in July 1730. (See Lalancle.) There was a project to make a canal from Versailles to the Seine at Sevre. The fall WM fOUIld to be 387-1 feet.
The Seine below Paris has much need of improve ment. In 1768 and t769, Captain Berthollet made four voyages from Havre de Grace to Paris, with the ship St. Ouen, of 160 tons, which had one mast of 96 feet, with a joint for passing the bridges; he employed four days in ascending to Poissey, v.hich is only 12 miles fiom Paris, and three days in going from that place to Paris. He sometimes employed sails, and sometinaes horses.
The Seine, from its mouth to Rouen, is incommo dious; and the numerous beds of sand ale constantly shifting. In 1747 the change was so favourable, that the flux and reflux became sensibly stronger above Rouen ; but, in a memoir of the same year, a complaint is made that the commerce of Rouen had decreased one half from the imperfection of the navigation. It has been proposed to deepen the river by machines, and patents were granted; but the progress was small and the ex pense great. It has also been proposed to deepen by floating jetties.
The river from Rouen to Paris is navigable only fottr months in the year. The great boats of Rouen are 191 feet long, they carry 350 tons, are drawn by 12 horses, and take 18 to 20 clays in going to Paris. The small passage boats take at least five days, but more generally 12 days. It has been found most advisable to employ boats drawing from three to five feet water. Three locks have lately been constructcd upon the Seine, viz. one at Pont de l'Arche; another at Isore ; and a third at Vernon.
The Oise receives the stream Venettes half a league below Compiegne; the sand bars the mouth so much, that boats are obliged to be lighted. Corn and wood are carried upon it in half loads. In 1766 the boat men of the Oise gave in a memorial to have it cleaned to Verbine.
In Picardy two canals have been completed, and a third begun. That from the Oise to the Somme, named also the canal of Fere or canal of Crozat, was finished in 1738. NI. de Marcy, in 1721, proposed a canal from the Somme to the Oise, which, near St. Quintin, are only 10 miles apart. By an edict of September, 1725, the king appoints NI. Caignart, and assistants, to construct a canal between the Somme and the Oise, to commence at the lake of St. Quintin, passing Hat.ly, Hambliers, Nlarcy, Rcgny, and Sissy, near Oise, to Fere ; to deep en the river Oise from Sissy to Chalney ; and to ren der the Somme navigable from St. Quintin to Amiens, and from Amiens to Perpigny. In 1727 operations com menced by a company, to which Regirnorte was engi neer ; but it appeared that the best line had not been chosen, for in 1752 the line was carried past \rimy, Con drun, Fargnier, Quessy, Liez, Menessies, Jussy, and St. Simon, to Pont and Thugny sur Somme, the point of partition. The plan was published in 1732. (See Be lid. -*ch. IIydraul. b. iv.) From St. Quintin to La Fere the distance is eight leagues; from Fere to Chaulney on the Oise, by the canal, three leagues ; from Chaulney to Sampigny, by the river, five leagues. In 1766 the king was requested to purchase the canal of Picardy, or suffer it to be destroyed, and the materials sold. The king be came purchaser. The canal between the Somme and the Oise was begun in 1728, and finished in 1738. In 1-768 and 1769 NI. Laurent examined the state of the Somme, and in consequence of an aria of council, May, 1770, improvements were commenced between St. Si mon and Ham. In 1771 the liver could be navigated between St. Simon and Clery, three miles below Pe ronne, that is, including windings, about 20 miles, or one half the navigation ; the channel of the river being crook ed, much use could not be made of it, a canal was there fore excavated, chiefly along its sides. Below the an cient city of Bray, the canal entered the bed of the Somme, and continued in it past Corbie, eight miles to Amiens. In 1777 operations were recommenced bY Dupliex. In truth, the Somme, which was formerly navigable above St. Quintin, 1101V ceases to be so below it, and they have been obliged to substitute a canal. The mouth of the Somme is also much obstructed.