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 feet; length, from upper to lower gates, 82 feet. On the Buckingham Branch, at the junction with the Old Stratford Branch, the locks are 7 feet wide, with a rise of 13 feet; the rise of the other locks averages about 7 feet each, and require nearly two hundred and fifty tons of water to fill them. The communication with Northampton and the River Nen is by a double railway, allowing carriages, going different ways, to pass without interruption. The two tunnels average a width of 15 feet, and a height of 19 feet; that at Blisworth is 60 feet below the summit of the hill, through which it is excavated. There is a line of deep cutting through the great chalk-hills between Cow-Roost and Bulbourne, which is three miles long, and, in some parts, 30 feet deep; near Blisworth Tunnel, and at Dawley, there are also great lengths of cutting of considerable depth; and, between Wolverton and Cosgrove, there is a very lofty embankment, with three aqueduct arches, at the crossing of the Ouse River: by means of this embankment nine locks are avoided, and a length of twelve miles of level pound on the north side of the embankment is held up by a single lock of 18 inches rise. The embankment is half a mile long, and, at the crossing of the Ouse, 30 feet high. An unfortunate mistake occurred in taking the levels near Fenny Stratford, for rectifying which it was necessary to place another lock of 18 inches rise, in order to hold up a pound of some miles, which otherwise would have been united to a level pound of ten miles near the same town. There are various embankments at Weedon Beck, Bugbrook and other places, which it would be superfluous to notice particularly, though several of them are of considerable size. Some extensive pieces of water are on the canal in different places; the largest being at Harefield Moor, Great Berkhampstead, Halton Park, and Wendover. In a line which passes through the ponds of so many mills as this does, it is necessary to have a more than ordinary number of reservoirs to supply the consumption of water in these, as well as in the canal itself; the Grand Junction has five; one at Daventry, another at Weston Turville, and a third at Braunston; these are all of large size. There is also one at Wilston, covering forty acres of ground; but the largest is at Aldenham, covering above sixty acres.

Several feeders are connected with this navigation on different