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30 VINU AIMRORLIAD

ment on the side of the canal. The ladder over which the buckets travel is raised or lowered by a mammoth crane and swung from side to side by guys worked on steam winches, so that the buckets can excavate at any angle. Each dredge excavates about fifteen cubic yards of earth a minute. Working abreast the two dredges named cut the canal, as they proceeded, to its full width, 280 feet. However, they cut only seventeen feet below the surface of the water, and as the required depth of water in the canal is twenty-eight feet, the remaining eleven feet will be cut by other dredges following behind these. About one mile of the canal had been opened at the close of 1891. At the same time about nine miles of the canal clearing had been made through the forest on the Pacific side of the lake.

A brief glance at the canal route in its entirety, before proceeding to consider the work remaining to be done, will give the reader a more comprehensive grasp of the subject. The distance from Greytown to Brito, the Pacific terminus of the canal, is 169 miles. The actual

excavation required, however, is only 26 miles, of which 15 miles are between Greytown and the San Juan River, and 111⁄2 miles between the lake and the Pacific. The distance traversed by the canal to the San Juan is 313 miles, of which 16 will be through artificial lakes or basins. The course of the canal between the lake and the Pacific will also be through an artificial lake 5 miles long. For the major part of the distance between the two oceans, sixty-five miles of river and fifty-six miles of lake navigation will be utilized. Three locks, within thirteen miles of the Atlantic, will lift the canal 106 feet above the level of the ocean, and the natural incline of the river, which is three-fourths of an inch per mile from the lake to the point of junction, will raise it to the summit level, 110 feet. Three locks within 31 miles of the Pacific will lower it to that ocean. Thus the summit level of the canal will be 1531 miles long.

Although a work of great magnitude, no insuperable engineering difficulties are presented anywhere along the route. The hardest part of the work lies in the eastern and San Francisco

divisions. The eastern division extends 187 miles, from Greytown harbor to the western end of the eastern divide cut, and the San Francisco division, 121⁄2 miles, through the basin of a river of that name, from the cut to the San Juan. For 9 miles, from Greytown harbor to the first lock, situated in the foothills of the eastern divide, the course of the canal is southwest across the flat alluvial coast lands, where the excavation will be made entirely by the floating dredges. This section of the canal, which will preserve the sea level, will have a surface width of 280 feet, a bottom width of 120 feet, a depth of twenty-eight feet and a waterway cross section of 5,712 square feet, or 2,012 square feet more than the cross section of the Suez Canal. All of the locks on the canal will be 650 feet long, eighty feet wide, and capable of receiving at the same time two vessels of 2,500 tons each. Lock No. 1 will have a lift of thirty-one feet; Lock 2, situated 14 miles further west, will have a lift of thirty feet, and Lock 3,2 miles beyond the second, a lift of forty-five feet. Between Locks 1 and 2, the

canal will be carried through an artificial basin

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