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ing of the canal off Port Tewfik; deepening of the would render fertile a broad belt of desert-land basin of Port Tewik; and the continuance of the to the north, constituting the whole interior of masonry-work.

Algeria and Tunis, where there are numerous They at the same time suggested the advisa-fresh-water wells, and where nothing but rain bility of cutting a second canal parallel to the is wanted to make the soil exceedingly profirst, in anticipation of a still greater traffic. ductive. The cutting would be through sand, This scheme was the subject of the negotiations except in some places where a calcareous rock between M. de Lesseps and the British Govern- is met with ; which, however, is hardly more ment. The section of the Suez canal is too than sufficient to furnish materials for breaksmall for vessels of such dimensions as are now waters, piers, and buildings. The total cost is built for the Indian and Australian trade, irre- estimated by M. de Lesseps at 150,000,000 spective of the question of overcrowding and francs, and the time to complete it five years. blockades. The passage is too narrow and shal Panama Canal.—The works on the Panama low to allow them to steer properly, particu- canal are progressing, though, from the inalarly at such a slow speed as five knots an bility of M. de Lesseps to raise a new loan in hour, the maximum in the present canal. It the spring, it is evident that the feasibility of was on this account that the English ship-own- carrying out some important features of the ers, in their conferences with M. de Lesseps original plan is doubted. The reports of the in the latter part of the year, urged the neces director general, M. Dingler, on the excavasity of enlarging the section of the present tions are encouraging. The quantity of earth canal as more pressing than that of separate to be removed is placed at 100,000,000 cubic channels for vessels going in opposite direc- metres, instead of 80,000,000 as previously estitions. He promised to meet their views and mated, but the absence of the expected rock bave the plans for the improvements drawn up excavation, and the looseness of the soil, reon the basis of an enlargement of the present duce the estimated cost from 10 francs a metre canal, which will take precedence, and a corre- to about one third of that rate. Much of the spondingly larger sectional area in the pro- excavation is done by negro laborers, who work jected parallel passage.

more cheaply than the machines which were Isthmus of Corinth Canal.—The Isthmus of Cor- brought for the purpose. M. de Lesseps estiinth canal, which was begun in the spring of mates the total cost at 500,000,000 francs, not 1882, and is expected to take four years, pro- including the reserve fund of 100,000,000 francs ceeds with greater rapidity since the intro- for unforeseen expenses. He asserts positively duction, in the autumn of 1883, of gigantic that the canal will be completed within the steam-excavators constructed in France. The five years originally calculated, which end in length of the canal is 6,342 metres. Its depth 1888. and width are the same as those of the Suez The proposed high dam in the valley of the canal. It will save ships from the Adriatic Chagres is one of the most dubious features in trading with Greece, Turkey, the Danube, or the canal plans. The reservoir at high water the Black sea, as much as 185 marine miles, is to cover an area of 6,750 acres, and contain and those from the Mediterranean and Atlan- 1,000,000,000 cubic metres of water. The ditic about half that distance. At present 5,800 rectory has abandoned the idea of building the large steamers and 300 war-vessels, besides a canal without locks, and determined to make large number of sailing-craft, sail around Cape a lateral canal and three locks at Panama. Matapan every year, enough to furnish the The total length of the canal from the Atcanal, to begin with, a traffic

of nearly 6,000,000 lantic to the islands of Naos and Flamenco, tons. The site of the new town of Isthmia, at where it joins the Pacific, is 74 kilometres. It the Ægean outlet of the canal, is exceedingly is divided into 12 sections, the most important healthful. There was no mortality among the of which are Colon, Gorgona, Obispo, Emperaworkmen from climatic causes during the first dor, Culebra, and Paraiso. On all the sections year's operations.

30 steam-excavators, 40 locomotives, and 800 Sahara Sea.—M. de Lesseps, after a personal tip-wagons were at work in the autumn. The examination of the route of the canal with force of laborers was then 10,000 men, which which Commandant Roudaire proposes to in- number was expected to be augmented at the undate the chotts of Tunis and Algeria, declared beginning of the fine season in December to his adhesion to the project, which he has fa- 15,000. About two thirds of the grand cutting vored from its inception, and aided in its pre- between Obispo and Paraiso was excavated by liminary stages. The chotts, or alkaline basins, Oct. 15th. It is expected that in 1884, when depressed below the level of the Mediterra- all the machinery will be on the ground, the nean, extend in an irregular chain from Gabes excavations will proceed at the rate of 4,000.to the town of Biskra in the desert, 300 miles 000 cubic metres a month. On Oct. 15th the inland. The large lake which would be formed harbor-works at Colon were nearly completed. by flooding the depressed area would be not An entire town had sprung up there, with less than 2,000 or 3,000 square miles in extent, numerous workshops and warehouses, and conand deep enough to float the largest vessels, necting railroads for the distribution of matewhich conld enter easily by the nearly straight rial. The terre plein and breakwater were canal. The creation of such a landlocked sea finished. A cutting was opened at the spot

called Monkey Hill, with the object of filling was turned into its former course by means of up the lagoons at the bottom of the bay of a dam constructed in 1837 or 1838, by order Colon, in order to improve the sanitary condi- of the Khan of Khiva, to prevent the Russians tions. The 120 horse-power dredgers remove, from using it as an avenue of approach to his each of them, 6,000 cubic metres of earth a capital. In 1853 the Russians broke the dam day. The machines of the Franco-American and allowed the waters to flow into the dry Trading Company, which were built in Lock- bed of the Jany Darya, but finding that the port, N. Y., excavate 2,000 metres. This com- Syr Darya was rendered too shallow for steampany has contracted to dig the Pacific opening boat communication, they restored the work. from the mouth of the Rio Grande to Paraiso In 1883 a channel was reopened, and the within the term of two years.

water soon penetrated as far as Irkibai. Florida Ship-Canal.—A project for a tide-water Whether the main volume of the river can canal across the upper part of the Florida be diverted into the new course, and whether Peninsula has been taken up by a company it can be made to flow into the Amou or the formed for the purpose. The commercial Sea of Aral, is still doubtful. The work alprospects of this canal are more enco aging ready accomplished will restore fertility to & than those of the again intermitted Cape Cod large portion of the Kizil Kum desert, and imcutting, for the 800 miles of navigation which prove the military and caravan communicait will save were described by Commodore tions with Khiva and the Amou Darya station. Maury as being as dangerous as any in the Drainago of Lake Okechobee.—The reclamation world. The annual losses from wrecks on the of swamp - lands on an enormous scale has southern coast of Florida are computed to been undertaken in Florida by an association amount to $5,000,000. A saving of 1 per cent. of American and English capitalists. The in insurance is therefore counted on. The Florida Land Improvement Company, organcommerce which goes through Florida Pass ized by Hamilton Disston, of Philadelphia, in annually is said to be three times as great addition to 4,000,000 acres of State lands which as the traffic of the Suez canal. The route were obtained by purchase, selected, and in selected is from a point on the Suwanee river, great part resold, one half being taken by an to a point above Jacksonville on the St. John's English syndicate and several hundred thousand river--a distance of somewhat over 60 miles. acres of the remainder by other purchasers, The estimated cost is $20,000,000.

received authorization to drain the Okechobee The Iron Gate. The removal of the obstruc- district, covering 11,000,000 acres, on terms tions in the cataracts and narrows of the Dan- giving the company for its service one half of ube, called the Iron Gate, at the point where the land roclaimed. There are some sections the Austro-Hungarian, Servian, and Rouma- in the overflowed lands, as well as in the pinenian boundaries meet, was attempted in 1781, lands of Southern Florida, which are supand again in 1834. The scheme has been de- posed to be as well adapted to the cultivation ferred up to the present in pursuance of the of sugar as any soil in the world. The cane protective policy of the Austrian and Hunga- can be harvested in saccharine maturity, as rian Governments, which feared the compe- the region is south of the frost - line; but tition of foreign manufactures, and even of whether it will propagate itself for a sucAmerican grain. In 1883 it was again taken cession of years by ratooning, as in Cuba, is up, and arrangements were made for the final not yet established. These lands are also execution of this important and difficult work suitable for jute, which is grown in Florida of engineering. On June 4th, an accord was of a superior staple and luster. The feasi. reached between the Austrian and Hungarian bility of draining Lake Okechobee was esministries, in a conference at Vienna, by which tablished in 1879, in a survey ordered to be the Hungarian Government undertook the regu- made by the Federal Government. Col. Meigs, lation of the river. The agreement of Servia who conducted the survey, calculated the level and Roumania was obtained. The cost is to of Lake Hickpochee, connecting with Lake be reimbursed by the levy of tolls for the Okechobee, to be 22 feet above mean low period of ninety years. The various estimates tide. A survey, made in 1881 demonstrated range from 10,000,000 to 22,000,000 forins. that the elevation of Lake Okechobee above The general plan which was adopted was the low-water level of the Atlantic ocean was worked out by the American engineer Mac- 25 feet. When Lake Okechobee overflows Alpine.

its banks and backs the waters of its numerDiversion of the Syr Darya.—Schemes for ous tributaries, submerging the entire surchanging the course of the Syr (Jaxartes) and rounding country, a portion of the overflow that of the Amou (Oxus) have been under the finds its way into the Gulf of Mexico by slugconsideration of the Russian Government for gish and tortuous channels through Coloosasome time. Both of the principal rivers of hatchie river and other outlets. The company Turkestan have followed different channels at began to cut a canal from the Coloosahatchie different periods. The partial diversion of the in January, 1882, and made connection with Syr into the bed of the Jany Darya is a work the lake on Dec. 10, 1882. A steady current of no great difficulty, as it was accomplished set through this channel, which relieved a by the Kara Kalpaks about 1760. The river large surface of swamp-land adjacent to the

lake, and lowered the level of the neighbor- be unloaded and brought up again. Hydraulic ing lakes. The outlet canals connecting Oke- power is used also in drawing the barrows chobee with the Coloosahatchie river are to which bring the excavated material up an inbe made navigable. The first one made is cline to the banks, where it is used for filling 52,000 feet long. The company next deepened up. The larger of the two graving docks is and straightened the Kissimmee and Little 550 by 65 feet at bottom, with 211 feet of rivers which connect the Tchopekaliza lake water on the sill; the larger one is 512 by 81 with Okechobee. Canals 6 feet deep were cut, feet, with 194 feet of water. The pumpingand a current was obtained of 24 miles an hour. engines used in emptying the dry docks are By May, 1883, the level of the upper lake had employed also in maintaining the water in the fallen 5 feet. At that time 380,000 acres had main dock at the proper level, the supply being been redeemed. The excavation was done en- drawn from an inland stream which is freer tirely with steam-dredges.

from sediment than the Humber, Hull Harbor Improvements. The new dock at Arlberg Tunnel. The headings met in the Hull is intended to meet the growing demands great tunnel through the Arlberg in the Rhæof a port which, next to London and Liverpool, tian Alps on Nov. 14th. The tunnel is nearly has the largest commerce of any in the British 63 miles long, taking rank immediately after Islands. In connection with the New Barns- the St. Gothard and Mont Cenis tunnels. The ley railway, running to the Yorkshire collier- exact length of the new tunnel is 10,270 meies, the new dock enables Hull to become a tres, that of the Mont Cenis tunnel 12,823, large coal outport. The Humber brings ships that of the St. Gothard tunnel 14,900. The of deepest draught up to Hull at any state of object of the work is to shorten the distance the tide. Besides the river Hall, which winds between Austria and Switzerland, and to give through the town and constituted the old Austria direct communication with the railroad harbor, but which is available only for small systems of Western Europe and render her invessels at high water, there were seven wet dependent of the South German railroads over docks with a total area of 763 acres. The new which the traffic has hitherto had to pass. basin, called the Alexandra dock, is 463 acres Starting from Innspruck, the new line is carin extent, and a new one in course of construc- ried along the right bank of the Inn to Lantion contains 104 acres, giving the city a to- deck. At that point the difficult part of the tal area of wet-dock accommodation of 133} work began. From Landeck to St. Antoine, acres. The Alexandra dock will accommodate where the road enters the tunnel, the total the large vessels engaged in the grain-trade rise is 1,721 feet. The gradient in the valley with California and India. To construct it, of Rosanna is one in forty. The distance 150 acres of the foreshore were reclaimed by between Landeck and Bludenz, the other terembanking, of which 100 acres are occupied minus of the road, on the opposite side of the by the wet dock and two graving docks, their Arlberg in the Austrian province of Vorarlberg, quays, warehouses, roads, railways, etc. The is 35 miles. This section is a mountain railworks have a frontage on the river of 6,000 road all the way. The Panznau valley is feet, and a depth of 3,500 feet. The dock is crossed by a bridge of three arches, each of 197 2,300 feet long by 1,000 wide. It is entered feet span. The tunnel first planned by Gen. through a lock 550 feet long and 85 feet in Nordling, who surveyed the route, was a width, having three pairs of gates and a cais- smaller one higher in the mountain ; but the son at the entrance. The sea-bank between Austrian Government determined not to spare the basin and the river is 17 mile long, being expense in a work of so great political and composed of 200,000 tons of chalk, faced with commercial importance, and the tunnel was stone, with an outward slope of one in two. made longer, in order to lessen the grades, and The trumpet-shaped entrance, 360 feet wide, wider, so as to accommodate two tracks inis formed by timber wharves built upon creo- stead of one. soted piles. The depth over the sill is 34 feet The work of boring began in June, 1880, at high spring-tide. There are two jetties on the Austrian side. On the Swiss side thé 400 feet long, and one of 450 feet, within the heading was started in September of that year. dock. All the cranes, capstans, and other ap- The perforators used on the Austrian side were pliances, as well as the gates, valves, and percussion drills, constructed on the same syssluices, bridges, and hoists, will be worked by tem as the machines employed in boring the hydraulic machinery. This is already applied Mont Cenis and St. Gothard tunnels. Å sein a novel manner in the work of excavation. ries of 20 or 25 chisels, covering a space of 7 A hydraulic navvy is used, which is capable of square metres, were driven into the face of the removing 600 to 700 cubic yards of earth a day. heading with blows imparted in rapid succesUnlike the steam navvy, it can not be thrown sion by compressed air. The machines were out of order by giving it more work than it can actuated by turbines at the end of the gallery, do, as it stops when driven beyond its capacity, The chisels penetrated the rock from 14 to 2 so that it can not get strained. Another ad- metres. The holes were then filled with dyvantage is that it takes only two men to oper- namite and the blast exploded, lengthening the ate it. It is self-acting, depositing the earth drift about 17 metre. The perforators moved in tip-wagons on either side as fast as they can on wheels. The compressed air was applied

ander a pressure of five atmospheres through the seven-foot heading was excavated partly flexible tubes. On the Swiss side the new with Col. Beaumont's boring-machine, which Brandt perforator was employed. This ma- was set for f inch per revolution, equal to 4 chine excelled the performance of the Ferroux inch per minute, which was a slower speed apparatus used at the other end, which is the than was made in the gray chalk of the Chanlatest improvement in the percussion porfo- nel tunnel. Through this seven-foot drift. rator. The new perforator consists of six or way the water which entered flowed down the eight veritable drills, with a diameter of 70 incline to the shaft at each end and was got millimetres, wbich bore into the rock with a rid of by means of the steam-pumps. The rotary movement under a hydraulic pressure tunnel was excavated at a higher level, the of from 60 to 100 atmospheres. The differ: work proceeding at some distance in the rear ence in the speed at which the work proceeded of the advance of the drift-way. The tunnel is in the different Alpine tunnels shows the prog- semicircular, and hus a breadth of 26 feet and ress made in boring machinery. The Mont a height of 20 feet above the rails, the radius Cenis tunnel advanced at the rate of 3,637 feet of the curve varying froin 40 feet at the base a year; the St. Gothard at the rate of 5,474 to 13 feet in the arch. The gallery, as it was feet; and the Arlberg at the rate of 7,080 feet. quarried out, was lined all round with massive The improvements reduce the expense in a walls of brick and cement. The heavy blocks still greater ratio, the Arlberg tunnel having of stone, which were blasted out with gelatine, cost only $750 per lineal metre, as compared were removed on cars in a constant rotation. with $1,250 per metre in the St. Gothard, and On the Cheshire side, where the Beaumont $2,000 in the Mont Cenis works; althongh a borer was used, a compressed-air locomotive part of this saving was due to the relative of Col. Beaumont's invention was employed to shortness of the Arlberg bore.

remove the excavated rock. The work of carrying away the excavated Hitherto the only connection between Livermaterial in mountain tunneling is as difficult, pool and Birkenhead, where the railroads of and consumes quite as much time, as that of Cheshire and Wales converge, has been by excavating. The gases from the explosives ferry. Various plans for carrying a railroad render this task unwholesome and sometimes across the Mersey, by a high bridge or a tundangerous. In the Arlberg the miners escaped nel, have been proposed by engineers before. ill effects by covering their mouths and nos- The tunnel finally constructed is the shortest trils with sponges steeped in vinegar.

and most direct route, one end emerging in the At first, owing to the hardness of the rocks center of Liverpool, and the other in the cenon the western side, and to the inflow of enor- ter of Birkenhead. The grades are consemous quantities of water, the stipulated rate of quently heavy. The tunnel is expected to be progress, about ten feet a day, could not be opened to traffic in 1885. made; but after the water was subdued the East River Bridge. - The suspension-bridge advance was more rapid than the prescribed over the strait called the East river, which speed. The gallery was driven on a level with separates New York from Brooklyn, on Long the bottom of the tunnel, and not, as tormerly, Island, was completed and formally opened on on the Belgian system, i. e., on a level with May 24th. The project of a bridge to connect the top. The cost of the tunnel itself is esti- the two cities and furnish safe and rapid com. mated at 18,000,000 forins, including the pre- munication, was originally brought forward by miums earned by the contractors for early com- William C. Kingsley, President of the Bridge pletion, in which premiums they allowed their Trustees, and Henry C. Murphy, his predeworkmen to share. The cost of the whole line cessor in office. Mr. Kingsley selected the will be about 40,000,000 florins.

site, and had plans and estimates prepared, as Mersey Railway Tunnel.—The headings of the early as 1865. The Bridge Company was ortunnel under the river Mersey met in the cen- ganized in 1867, with a nominal capital of $5,ter before the end of the year. Though insig- 000,000, the amount of the preliminary rongh nificant in length, the river being less than a estimate of the engineer, $500,000 of which mile broad at that point, this tunnel is a work was subscribed by citizens who formed the of great difficulty, owing to the low level at company, $3,000,000 was to be furnished by which it has to be carried under the deep Brooklyn and $1,500,000 by the city of New waters of the Mersey, the toughness of the new York. In 1875 the bridge was made a State red sandstone, the amount of pumping neces- work, and placed in charge of a board of trussary to remove the immense quantity of water tees. John A. Roebling, the originator of wire which perforates through this porous rock, the suspension-bridges, was the engineer. His work of lining the gallery to stop this inflow, estimates in 1867 made the cost of the bridge and the precautions which were necessary $7,000,000, and of the approaches $3,800,000. against a possible fault in the geological forma. The estimated time of construction was five tion and the inrush of water from the river. years. A commission of bridge engineers apFortunately, the stratum was found to be con- proved his plans. Congress passed an act in tinuous. The roof of the tunnel is separated 1869 authorizing the construction, and in June from the bed of the river by a thickness of 30 of that year the Secretary of War decided feet. The length of the tunnel is 1,753 yards. that it would not impede navigation, providing

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