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way to be realized. The commission appointed the deficient water-supply, was enough to conby the United States Government to consider demn the plan. The route between the gulf its feasibility, and select the best route, have of San Blas and the river Chepo or Bayanos presented a final report; and treaties are in has been supposed to be a specially desirable progress with other countries concerning it. one, because the tides from both oceans are The Dutch have achieved a great engineering nearer together at this point than elsewhere; success in the completion of the North Sea but the survey revealed insurmountable diffiCanal, which makes a seaport of the city of culties, even after an eight-mile tunnel should Amsterdam, floating the largest vessels, and have been cut. A survey from Caledonia Bay allowing direct steamboat communication with out discovered no pass at a less elevation than foreign ports. The St. Gothard Tunnel is ap- 1,000 feet. Several other routes which were proaching completion ; but its undertakers surveyed showed difficulties still more formihave been greatly dismayed by the discovery dable. The Government has expended about of an enormous miscalculation in the estimates $60,000 in this investigation. of cost. Extensive and costly experiments The treaties with foreign powers are to be upon the proposed railway-tunnel through the made on the basis of the Clayton-Bulwer chalk-beds underlying the straits of Dover are Treaty of 1850, guaranteeing the neutrality of undertaken, and will amount to a commence- the canal. The estimate of the cost returned ment of the work, if it shall be found feasible. by the commission is $65,722,157 ; but several In Italy we see the completion of an enterprise practical engineers, who have examined the which has been pursued for many years, by route, conjecture that obstacles will be enwhich a large tract of land, submerged for countered which will increase the cost to ages, has been recovered to agriculture. Other nearly $100,000,000. The work cannot be similar works are proposed for the reclamation completed in less than five years of hard labor; of the wide ranges of land which lie waste in but if it is sustained by the leading governthat country, covered with disease-generating ments, it is supposed that it will not be delayed marshes; while in Holland a plan is seriously or abandoned for want of funds. The distance entertained by the Government for the drain- to be excavated is 614 miles, and the total ing and fertilization of the bed of the Zuyder length of the canal, including 53 miles of slackZee, which would increase the territory of that water navigation, by way of the San Juan country about one-sixth, and afford å perma- River, and 56 miles across Lake Nicaragua, nent revenue of millions of francs to the Gov- will be 1804 miles from ocean to ocean. For ernment. The long-expected Russian railway a number of years there has been a consideracross Central Asia
has not yet been practically able and increasing transportation traffic by commenced, though the project is gaining the way of Lake Nicaragua and the San Juan favor. In our own country, the great works River. Whether a ship-canal across the Nicaof river and harbor improvement, which have raguan Isthmus would draw any of Europe's been carried on by the Government, are still trade with the East from the Suez Canal is under vigorous prosecution; the chief results doubtful; but the benefits it would afford to the of this year's labors have been the clearing American trade with the East and the Pacific away of Hallett's Reef, one of the most serious coast, and the improved communication it obstructions in the East River channel (see would render between the western side of the article HELL-GATE), and the deepening of the North and South American Continents, and chief outlet of the Mississippi (see below). the whole commercial world, would be much
The survey which has been conducted by the more than commensurate with its cost. commission of the American Government for An American engineer, Henry O. Spalding, five years past upon the isthmuses of Panama has broached a scheme for letting the waters and Nicaragua, with reference to a ship-canal, of the Black Sea into the Caspian through an has been completed within the year, and final artificial channel-way, thus greatly enlarging reports have been presented to the President. the area of the latter sea by the submersion of The route which was found most promising comparatively sterile tracks, but immensely and practicable was one across the Nicaraguan improving the fertility of the surrounding Isthmus, by way of Lake Nicaragua. Four other regions, and giving Russia maritime communiproposed routes have been carefully examined. cation with the commercial world, and a broad The one across the isthmus of Panama, for- sea-coast. His project is to cut a canal, 150 merly much thought of, was found to present metres wide, from a point in the basin of the the greatest difficulties. J. C. Trautwine, chief- Caspian Sea, which is 15 metres below the engineer of the Panama Railroad, lately ex- level of the Black Sea, in a westerly direction pressed an opinion that a canal over that route to such a point that it will have a depth of 10 would cost not less than $300,000,000! The metres; from there a narrower cutting is to be survey across the isthmus of Tehuantepec, carried on to the Black Sea. This narrower ander Commodore Shufeldt and Engineer channel, he calculates, should have a depth of Faertes, showed that the line proposed by three metres where it strikes the Black Sea, and those engineers by way of the river Coatzaco- a width of 50 metres; through this the water alcos would require the construction of as would flow with a velocity of 12 kilometres many as 140 locks, which, in connection with an hour, and, where it gives into the larger
channel, would have a fall of 10 metres, which by 46; and both are built upon no fewer than would give it a tremendous excavating power. 8,896 piles. The tremendous driving force of It would take about six years, he reckons, to the storms on the North Sea, and the shifting complete the excavations, and then about sands of the coast, gave rise to difficulties forty years for the waters of the two seas to which taxed all the resources of engineering approach near enough to a level to allow of skill. The plans of this great work were denavigating the canal. This time can be short- vised by the English engineers Sir John Hawkened to twenty-five years, he further proposes, shaw and Darnton Hutton. The canal receives by connecting the rivers Don and Volga vessels of any tonnage. At intervals it is enthrough another cutting.
larged into basins like the Suez Canal. The scheme of letting the waters of the At The plan for draining the Zuyder Zee was lantic into the desert of Sahara is gaining pronounced practicable and advisable by a favor. M. de Lesseps has expressed his opinion Government commission in 1873. During the that it can easily be realized, and advocates last couple of years it has been much discussed also the connection of the Congo and Zambesi in the Legislature, in the chambers of comrivers by a canal at the point where they ap- merce, and by the press; and there seems every proach each other within eighteen miles, both likelihood that its practical execution will soon being navigable at that point. He considers be commenced. The most difficult part of the that the climate of Europe would be improved, work will be the construction of a great dike if anything, after the submersion of the desert, across the lake, from the town of Enkhuisen to and suggests that the fertile oases are all above the island of Urk; and then, with two angles, the ocean-level.
to Kampen, on the east side. The length Reports on the improvement of the mouth of the dike is to be 40 kilometres, some 25 of the Mississippi show that the work is pro- miles, with a height of 8 metres, or 26 feet, gressing, and that satisfactory results have above high-water level, and a breadth of 50 already been attained. Grand Bayou has been metres, or 164 feet. Double sluices at Enkclosed, and the water which passed through it huisen, Urk, and Kampen, will communicate now makes its way through the pass, increas- with the sea. Alongside of the dike a canal ing the current and its scouring forcé greatly. will be made on the inside, and on the interior The width, depth, and straightness of the berm will be the tow-path and a railroad. channel are improved, and a recent statement The plan for draining the lake is to divide it of Captain Eads shows an average depth of into squares, which are to be successively 20 feet through nearly the whole length, the pumped out by immense steam-engines into exceptions being a spot near the upper end of canals of discharge, which will convey the the pass, and one within 1,000 feet of the water into the large permanent canals of marilower end of the jetties, about 75 feet together, time communication, leading into great reserwhere the depth is 19 feet in the shallowest voirs, from which the accumulated water will places. Captain Eads declares that the allu- flow out at low tide. Large commercial cavium carried out of the pass on the jetty sys- nals will be constructed between the harbors tem is not deposited so as to form a new ob- now situate upon the lake, of dimensions apstruction outside ; but that, on the contrary, a proaching those of the new North Sea Canal large lump at the mouth of the South Pass has from Amsterdam. The largest of the canals been cut through by the increased strength of will be one from Enkhuisen to Amsterdam, the current, and is being gradually worn away. and one starting near Harderwyk, and going A series of dikes and wing-dams is in pro- along the southern shore to Huisen, then turncess of construction in the pass above the ing toward the Pampas, and joining the other jetties, which is intended to reduce the width line. Of the smaller order of canals, there of the channel gradually from 5,000 to 800 will be four principal lines, two parallel, runfeet, and accelerate the scouring out of the ning southwest and northeast across the bed pass.
of the lake, and two intersecting ones. For The Dutch opened the new North Sea Canal, the completion of the drainage, thousands of in the summer of 1876, amid festal rejoicings. small trenches and ditches must be cut over This canal, although but fourteen miles long, is the entire bottom in every direction. The of immense utility to the commerce of the construction of bridges and sluices will present country, and of the highest importance to the greater difficulties than the work of canalizaprosperity of Amsterdam ; and its construction tion. Three several kinds of sluices will have was attended with such difficulties as to place to be made—the great double sluices at Urk, it among the highest order of engineering Enkhuisen, and Kampen; and a score of others achievements. A great part of its course is of the same construction at all the crossings of over tracts which were submerged by an arm canals, the simple sluices for the outflow of of the Zuyder Zee, and had first to be pumped water, of which there will be three by the side dry to allow the bed of the canal to be dug of the three great double sluices, and the out. To prevent the sand-hills near the sea small sluices for irrigation, of which there from choking the canal, huge locks had to be will be great numbers distributed over the constructed. One of the locks is 315 feet long entire surface of the reclaimed lands. The and 59 wide, and another ship-lock is 239 feet mean depth of water to be drawn off is es
timated at 34 metres. If 9,400-horse power is 20,000,000 francs, to be devoted to harbor imapplied it is calculated that the lake will be provements. drained in about two years, at the rate of The tunnel under the English Channel, for 4,500 cubic metres per minute. The only effi- the commencement of which companies have cient power here applicable is supposed to be been formed in London and Paris, it is prothe steam-engine. After the steam-pumps posed to construct on the route proposed by have done their business, dredges will have to Sir John Hawkshaw, from St. Margaret's Bay be employed to dig out the bottoms of the to a point near Sangatte on the French coast. canals, and clear away the mud, where large In this course it is expected that it will pass structures have to be built. For the founda- through chalk-beds the entire way, while in tion of many of the heavy structures it will be the route proposed by M. Thomé de Gamond necessary to sink piles and bundles of fascines, it is known that several different strata would as has been done in the making of the great be encountered. The distance across the ChanAmsterdam Canal. The entire work, it is es- nel in the proposed course is 22 miles, which, timated, can be completed in from twelve to with the long approaches necessary, would sixteen years. The surface drained will be make 31 miles altogether. Shafts are to be 196,670 hectares, or about 795 square miles, of sunk on either shore to the depth of 450 feet which area about one-tenth will be taken up below high-water mark. At that depth driftby roads and canals. It is supposed that, with ways are to be driven, which will serve for the all allowances, there will be about 150,000 hec- drainage of the works when in progress, and tares of fine, tillable land. The expense of the of the tunnel permanently. The tunnel will undertaking is estimated at 240,000,000 francs, commence 200 feet above the driftway, with a large estimate, exclusive of interest. If thé an inclination of one foot in eighty down to Government should carry out the undertaking, the junction with the driftway, and then of as seems most likely, it is calculated that it one foot in 2,640 to the centre of the Channel, would bring in, after completion, an annual where it will meet that driven from the other revenue of 1,880,000 francs.
side. The dimensions of the tunnel will be Two enterprises for the reclamation of large those of an ordinary railroad-tunnel for two sabmerged tracts are successfully in progress tracks. A driftway, nine feet in diameter, it in Italy. The Ferrara Marshes, in Northern is proposed first to carry entirely through, Italy, are being drained by means of steam- which can afterward be enlarged to the size of pumps, constructed by John and Henry the tunnel. A machine for tunneling in chalk Gwynne, of Hammersmith, England. The area has been invented by Dickenson Brunton, an to be reclaimed is 200 square miles. The en- English engineer, which has been successfully gines lift 2,000 tons of water per minute tried upon the bed of gray chalk through which through an average distance of seven feet three the tunnel is to be made. It works similarly inches. The maximum lift is twelve feet. The to an ordinary board-auger, cutting off the water is discharged into the river Volano, at chalk in slices, which fail upon an endless Cordigoro. Another large enterprise is the band, and are loaded upon wagons. The madrainage of Lake Fucino, which lies about 55 chine, it is found, can cut a driftway of seven miles east of Rome, and has an area of sixty-one feet diameter at the rate of something over a square miles, by means of a siphon 1,500 yards yard an hour. At that rate it would take two long, from canals which have been dredged out years to complete a driftway under the Chanat the bottom. The works have been going nel with a machine starting from each side. on many years, at the expense of the late The expense of completing such a driftway is Prince Torlonia, and the enterprise will soon estimated at £800,000, including interest upon become remunerative. This area was drained the outlay. Engineers and contractors of exby the Emperor Claudius, and the ancient perience have calculated that, after the driftworks were suffered to go to decay in the way should be completed, it would take four middle ages. The project was at first designed years' time and £4,000,000 only to enlarge it to restore the Roman works, and a company to the dimensions of a raiload-tunnel, and to was formed in 1855 for that purpose, and the construct the junctions with the railways work was intrusted to M. de Montricher, a on either side. It seems certain now that well-known French engineer. This was found the commencement of this work will soon be impracticable, and, the Prince Torlonia assum- made and its practicability tested. The coming the entire responsibility, the present works panies which have been formed for this purwere constructed. About 50,000,000 francs pose are to unite with the French and English have been expended upon them thus far. railways interested, and with the Rothschilds
There are suggestions of extensive improve- of London and Paris, in making up the sum of ments in the harbor of Genoa, and various £160,000, to be expended upon sinking a shaft plans have been proposed for the work. It has on either side to the depth of 450 feet, and drivlong been the dream of the Genoese to make ing a headway a short distance under the sea. their harbor the best in the Mediterranean, and The project of a tunnel under the North regain their ancient commerce and prestige on River from New York to Jersey City, for railthe seas. A nobleman of Genoese birth, it is way transportation, for which a company was said, has presented the city with the sum of formed some time ago, gave rise to a long
contention in the courts with the Delaware at Tandjong-Priok, to be formed by two break& Lackawanna Railroad Company. The tun- waters, 1,963 and 1,743 metres in length renel company has come out victorious in the spectively, and rising 24 and 11 metres above litigations, and nothing now lies in the way low-water mark, with two inner harbors, of of the enterprise. The works were begun which only one is to be constructed for the a long time ago, and now will probably be present, each having a length of 1,100 metres, pushed forward to a speedy completion. The and a basin 71 metres deep and 175 metres in capital stock of the company is to be $15,000,- width. The entrance to the outer harbor will 000, of which, it is said, $10,000,000 has already be 250 metres wide and 8 metres deep at low been subscribed; Senator Jones, of Nevada, is water. There will be 1,500 metres of quay, said to be an active promoter of the enterprise. and a channel 50 metres wide leading to a The project was first advanced by D. C. Has- coaling station. Between the harbor and Bakin, of New York, who is the president of the tavia a canal, five miles long, and a railroad, are corporation. The beginning of the work was to be built. The cost of the entire works will the sinking of a vertical shaft lined with brick be $15,000,000; but for the portion to be conmasonry of three or four feet thickness, having structed forthwith the estimate is something a diameter of 30 feet, in Jersey City, at the more then half that amount. junction of Jersey Avenue and Fifteenth The first wire carried across between the Street. When the shaft shall have been sunk towers of the Brooklyn Bridge was fastened on to the depth of 65 feet, the horizontal cutting the 22d of September. This great work, after will be commenced. The direction of the tun- seven years of labor and the expenditure of nel will be northeast and southwest. It will $6,750,000, is still a long way from completion. have a length of about two miles; the terminus The entire estimated cost of the completed on the New York side will be near Washington structure is now set at about $11,250,000, or Square. It will descend from both ends tow. more than double the original estimate. ard the centre in a gradient of two feet in 100. The contract for the construction of the proThe diameter of the tunnel is to be 26 feet. posed railroad-bridge at Poughkeepsie, over the Its roof will be nowhere less than 35 feet Hudson River, has been taken by the American below the bottom of the river, so that there Bridge Company, of Chicago. The main part will be no danger from the anchorage of ves- over the water will consist of five spans of 525 sels. Little blasting will be required, and the feet each between the centres of the piers, two or three veins of rock which will have to whose breadth will be 25 feet. The bridge be penetrated are of soft substance; the first will be of the description called the undervein of rock to be encountered crops up about grade or deck bridge, and will have two tracks 1,100 feet from the New York side. After a and sidewalks, and an under and upper deck, few feet of the lateral tunnel shall have been the latter carrying the two railroad-tracks, excavated, an iron cylinder will be introduced, and the other à carriage-way of 16 feet clear in which the workmen will be protected when width. Each span is to have two trusses, 25 driving forward the tunnel. The cylinder feet between centres, of the rectangular dewill have hinged doors, and be provided with scription, with double intersections, the maan apparatus and tubes for introducing com- terial will be iron and steel combined. The pressed air from the surface.
trusses are to be 58 feet high, and the top of There is a proposal to carry a telegraphic the piers 135 feet above high-water mark, so wire across the African Continent, from Khar- that the elevation of the track above the river toom, where there is telegraphic communi- at high tide will be 193 feet. The approach cation with Alexandria, at a distance of 1,100 on the west side of the river will have one miles, to Delagoa Bay, the terminus of the span of 160 feet, formed by two trusses, 30 Cape lines. The distance between these points feet in height. The long approach on the is 2,300 miles; but extensions are in progress other side, extending across the town, will be which will shorten it to 1,500 miles. It is composed, as far as Water Street, of iron tressuggested that the trees might be utilized as tling, formed by three post-bents strongly telegraph-poles, and that depredations of the braced, and four lines of stringers of iron latnatives, who might covet the valuable iron of tice, making spans of 20 to 60 feet. Across the wires, might be prevented.
the Hudson River Railroad grounds, Water The Dutch Government have issued pro- Street and Dutchess Avenue, will be two spans posals for the improvement of the harbor at of 25 feet depth. Beyond, as far as the oppo Batavia, the capital of the island of Java and site side of Tallmadge Street, where the apof their East Indian possessions. The only proach ends, will be iron trestling, except at the communication between the town and the crossings of Tallmadge and Delafield Streets, present harbor, which has an excellent road- over which will be made two 90-feet spans. stead, has been by a canal 8 or 10 feet deep at The entire length of the bridge and approaches low tide. The present accommodations are will be 4,500 feet. The plan of the bridge entirely insufficient for the large steamers proper is a suspended girder, with parallel and which are employed in the Oriental trade, cradled cables, and two decks. The girder, since the opening of the Suez Canal. It is 1,680 feet in length, will be of wrought-iron, therefore proposed to construct a new harbor The supporting towers will also be of wrought
iron. The cables are to be of steel links and feet long between the centres of the eyes, and pins, which are required to posses a final break- as they approach the towers are to be longer ing strength of at least 80,000 pounds to the in such proportion that the horizontal distance square inch, and which will be subjected to a between the eyes shall remain 25 feet. The tension in the bridge of 20,000 pounds per largest links in their middle will not have a square inch. The pins are to have the form of greater sectional area than eight inches. The a perfect cylinder between head and nut. The towers below the track of the railroad will be links near the middle of the span will be 25 formed of cells of wrought-iron, and above the
track will have eight columns 80 feet high and to 200 feet between the piers. Between the 11 feet in diameter. Each chamber in the city and St. Helen's Island, whose centre is of lower tower will have twelve saddles and two the same elevation as the roadway of the bridge, pairs of compensating levers. These and their there will be six spans of lattice, one of 550 attachments will be carried by a frame that feet and the rest of 300 feet. The roadway extends in both directions across the saddle- will have but a single track; but on the island chambers and over the heads of all the columns side-tracks and a crossing-station will be made. of the tower. All the parts of the saddles and from the centre of this island to the water's the lever attachments for the stay system will edge four spans of 240 feet will be required. be worked in together upon this frame; and so on the other side of the island there will be that the parts will move together sufficiently to twenty-one spans of 200 feet to the other compensate the expansion and contraction of channel, and over that five spans of 200 feet, the main back-stays beyond what the tower the roadway on this side having a falling itself sustains. The saddles will move by steel gradient of 1:100. On the lower side of the rollers upon steel faces under the carrying- river embankments will be made, and connecframe. The anchorage of the cables will be in tions established with the Montreal, Portland the solid rock at both ends. It is expected & Boston, and the Grand Trunk Railroads. that this bridge will pave the way for a new At the other end there will be a junction with railroad to the West, with a route between the Quebec, Montreal, Ottawa & Occidental New York and Chicago only 921 miles long, a Railway; the distance between the two juncsaving of 50 miles over any existing line. tions is five and a half miles. In the navigable
A new bridge is to be constructed at Mon- channel the piers, which will be like those of treal, about four miles from the Victoria the Victoria Bridge, with heavy ice-breakers, Bridge, which is to be called the Royal Albert will have to be put down with caissons, in á Bridge, and will be the longest structure of the channel 40 feet deep, where the current is seven kind in the world. Its whole length, includ- miles an hour. The superstructure will be of ing the portion built over the land, will be iron lattice-work, each pier being crossed by 15,500 feet, almost exactly three miles. It will four girders, placed 18 and 14 feet apart; bestart from the level of Sherbrooke Street in tween the inner girders will be two street-car Montreal, and pass through the town at the tracks; between them and the outer girders beight of about 90 feet, with distances of 150 will be the roadways for teams, and on pro
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