The barrage at the head of the Nile delta, and the regulating sluices across the Nile at Assiut and Esna in Upper Egypt below Assuan, are examples of draw-door weirs, with their numerous openings closed by sluice-gates sliding on free rollers, which control the discharge of water from the river for irrigation.
The old man opened the door with a barrage of questions, allowing Dean no chance to escape the interrogation.
Since 1890 the barrage has done its duty without accident, but a work of such vast importance to Lower Egypt required to be placed beyond all risk.
The Assiut weir is constructed on a design very similar to that of the barrage in Barrage.
The so-called Esna barrage across the Nile (built 1906-1908) is 30 m.
This " barrage scheme " was discussed at considerable length, and its theoretical advantages were not universally admitted.
The crossing of the narrow defile over the canal between Inchy and Moeuvres was carried out according to programme, thanks in large measure to the intensity of the barrage covering the operation.
At the western end of the barrage begins the Ibrahimia canal, the feeder of the Bahr Yusuf, the largest irrigation canal of Egypt.
The Habra barrage holds 38,000,000 cubic metres; that on the Sig 18,000,000.
The task of constructing this great work was committed to Mougel Bey, a French engineer of ability, who designed and constructed the great barrage across the two branches of the Nile at the apex of the delta, about 1 2 m.
The barrage is the greatest, but by no means the only important masonry work in Lower Egypt.
There being at its head no weir across the Nile, the water in the Ibrahimia canal used to rise and fall with that of the river, and so the supply was apt to run short during the hottest months, as was the case with the canals of Lower Egypt before the barrage was built.
Of and terminus of a railway from Zagazig, on the edge of the desert south of Lake Menzala, and the starting-point of the caravans to Syria; Mataria (15,142) on Lake Menzala and headquarters of the fishing industry; Zifta (13,850) on the Damietta branch and the site of a barrage; Samant~4 (14,408), also on the Damietta branch, noted for its pottery, and Fua (14,515), where large quantities of tarbushes are made, on the Rosetta branch.
In 1847 Mehemet Ali laid the foundation stone of the great barrage across the Nile at the beginning of the Delta.
He was barely persuaded from ordering the barrage to be built with stone from the pyramids!
Definite orders had been given both by Cadorna and by Capello that immediately upon the opening of the enemy's bombardment the Italian artillery should reply with a fire of " counter-preparation " upon the enemy's trenches and zones of concentration, and that they should lay down a violent barrage as soon as there were signs of movement.
Remains of Christian churches were disclosed by the thorough exploration carried out in1895-1896in view of the Barrage scheme, under the direction of Captain Lyons.
Above the river's bed, allowing the water-surface up-stream of the barrage to be raised 7.2 ft., while the pressure on that work itself would not exceed 10 ft.
To render the basin lands of the Kena province independent of the flood being bad or good, another barrage was built across the Nile at Esna at a cost of £i,000,000.
Mougel's barrage, as it may now be seen, is a very imposing and stately work.
They soon resolved that it would be very much better if the original scheme of using the barrage could be carried out, and after a careful examination of the work they were satisfied that this could be done.
Thus the whole system broke down, the barrage was pronounced a failure, and attention was turned to watering Lower Egypt by a system of gigantic pumps, to raise the water from the river and discharge it into a system of shallow surface-canals, at an annual cost of about £250,000, while the cost of the pumps was estimated at £700,000.
The experiment was repeated year after year till 1867, when the barrage cracked right across from foundation to top. A massive coffer-dam was then erected, covering the eleven arches nearest the crack; but the work was never trusted again, nor the water-surface raised more than about 3 ft.