INLAND NAVIGATION.

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hundred and forty-four feet, towing-paths included ; its depth fix feet,and its length fixty-four French leagues. It is here to be observed, thatNorouse is the highest: part of the navigation, being about fix hundredfeet above the level of the two waters, from whence the ground hasalmost one continued descent to them on each side. On this spot, as wasbefore observed, Riquet made his bason, and collected his waters; andhither he brought his current of water from the adjacent mountain byan aqueduct five leagues in length, which contained between five andfix thousand cubic inches; and this stream being distributed in the twocanals last mentioned, forms, in every part, a body of water of above sixmillions of cubic feet.

When a vessel or barge in its pastage from Narbonne, after it hassailed through the canal that traverses the plain, has arrived at the footof one of theie locks, the gates are instantly opened, and the water sohemmed in rushes forth with impetuous violence, and, mixing with thatin the canal, forms one common level: when the vessel fails into the lockand the gates are shut again, the water which descends from the upperlock rises by flow degrees several feet in height, seldom less than sevenor more than twelve; the vessel accordingly rises with it till it comesto a level with the water contained in the second lock, by meansof which a vessel that is coming from Narbonne may pass without anyobstruction out of the first lock into the second, or one coming fromThoulousc may be introduced out of the second lock into the first, thegates of the second lock being shut: the vessel in the same mannermounts into the third ; and thus it ascends from lock to lock till itcomes to the top of distribution, and then by the same kind of convey-ance falls down to Thoulouse. To preserve the level, they have beenfrequently reduced to the necessity of turning and winding the canalround hills and rising grounds, and to fortify it with an immense numberof piles in those places where the earth was likely to give way. Thiscanal was conveyed by water bridges and stone arches over valleys; hillsand mountains were levelled; while through others a passage was cut

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