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ENGINEERING. 



channel, would have a fall of 10 metres, which 

 would give it a tremendous excavating power. 

 It would take about six years, he reckons, to 

 complete the excavations, and then about 

 forty years for the waters of the two seas to 

 approach near enough to a level to allow of 

 navigating the canal. This time can be short- 

 ened to twenty-five years, he further proposes, 

 by connecting the rivers Don and Volga 

 through another cutting. 



The scheme of letting the waters of the At- 

 lantic into the desert of Sahara is gaining 

 favor. M. da Lesseps has expressed his opinion 

 that it can easily be realized, and advocates 

 also the connection of the Congo and Zambesi 

 rivers by a canal at the point where they ap- 

 proach each other within eighteen miles, both 

 being navigable at that point. He considers 

 that the climate of Europe would be improved, 

 if anything, after the submersion of the desert, 

 and suggests that the fertile oases are all above 

 the ocean-level. 



Reports on the improvement of the mouth 

 of the Mississippi show that the work is pro- 

 gressing, and that satisfactory results have 

 already been attained. Grand Bayou has been 

 closed, and the water which passed through it 

 now makes its way through the pass, increas- 

 ing the current and its scouring force greatly. 

 The width, depth, and straightness of the 

 channel are improved, and a recent statement 

 of Captain Eads shows an average depth of 

 20 feet through nearly the whole length, the 

 exceptions being a spot near the upper end of 

 the pass, and one within 1,000 feet of the 

 lower end of the jetties, about 75 feet together, 

 where the depth is 19 feet in the shallowest 

 plases. Captain Eads declares that the allu- 

 vium carried out of the pass on the jetty sys- 

 tem is not deposited so as to form a new ob- 

 struction outside ; but that, on the contrary, a 

 large lump at the mouth of the South Pass has 

 been cut through by the increased strength of 

 the current, and is being gradually worn away. 

 A series of dikes and wing-dams is in pro- 

 cess of construction in the pass above the 

 jetties, which is intended to reduce the width 

 of the channel gradually from 5,000 to 800 

 feet, and accelerate the scouring out of the 

 pass. 



The Dutch opened the new North Sea Canal, 

 in the summer of 1876, amid festal rejoicings. 

 This canal, although but fourteen miles long, is 

 of immense utility to the commerce of the 

 country, and of the highest importance to the 

 prosperity of Amsterdam ; and its construction 

 was attended with such difficulties as to place 

 it among the highest order of engineering 

 achievements. A great part of its course is 

 over tracts which were submerged by an arm 

 of the Zuyder Zee, and had first to be pumped 

 dry to allow the bed of the canal to be dug 

 out. To prevent the sand-hills near the sea 

 from choking the canal, huge locks had to be 

 constructed. One of the locks is 315 feet long 

 and 59 wide, and another ship-lock is 239 feet 



by 46 ; and both are built upon no fewer taan 

 8,896 piles. The tremendous driving force of 

 the storms on the North Sea, and the shifting 

 sands of the coast, gave rise to difficulties 

 which taxed all the resources of engineering 

 skill. The plans of this great work were de- 

 vised by the English engineers Sir John Hawk- 

 shaw and Darnton Hutton. The canal receives 

 vessels of any tonnage. At intervals it is en- 

 larged into basins like the Suez Canal. 



The plan for draining the Zuyder Zee was 

 pronounced practicable and advisable by a 

 Government commission in 1873. During the 

 last couple of years it has been much discussed 

 in the Legislature, in the chambers of com- 

 merce, and by the press ; and there seems every 

 likelihood that its practical execution will soon 

 be commenced. The most difficult part of the 

 work will be the construction of a great dike 

 across the lake, from the town of Enkhuisen to 

 the island of Urk ; and then, with two angles, 

 to Kampen, on the east side. The length 

 of the dike is to be 40 kilometres, some 25 

 miles, with a height of 8 metres, or 26 feet, 

 above high- water level, and a breadth of 50 

 metres, or 164 feet. Double sluices at Enk- 

 huisen, Urk, and Kampen, will communicate 

 with the sea. Alongside of the dike a canal 

 will be made on the inside, and on the interior 

 berm will be the tow-path and a railroad. 

 The plan for draining the lake is to divide it 

 into squares, which are to be successively 

 pumped out by immense steam-engines into 

 canals of discharge, which will convey the 

 water into the large permanent canals of mari- 

 time communication, leading into great reser- 

 voirs, from which the accumulated water will 

 flow out at low tide. Large commercial ca- 

 nals will be constructed between the harbors 

 now situate upon the lake, of dimensions ap- 

 proaching those of the new North Sea Canal 

 from Amsterdam. The largest of the canals 

 will be one from Enkhuisen to Amsterdam, 

 and one starting near Harderwyk, and going 

 along the southern shore to Huisen, then turn- 

 ing toward the Pampas, and joining the other 

 line. Of the smaller order of canals, there 

 will be four principal lines, two parallel, run- 

 ning southwest and northeast across the bed 

 of the lake, and two intersecting ones. For 

 the completion of the drainage, thousands of 

 small trenches and ditches must be cut over 

 the entire bottom in every direction. The 

 construction of bridges and sluices will present 

 greater difficulties than the work of canaliza- 

 tion. Three several kinds of sluices will have 

 to be made the great double sluices at Urk, 

 Enkhuisen, and Kampen ; and a score of others 

 of the same construction at all the crossings of 

 canals, the simple sluices for the outflow of 

 water, of which there will be three by the side 

 of the three great double sluices, and the 

 small sluices for irrigation, of which there 

 will be great numbers distributed over the 

 entire surface of the reclaimed lands. The 

 mean depth of water to be drawn off is es- 



