SHIP CANALS.

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Artificial canals are amongst the oldest of inventions, for, centuries ago, they have been constructed, even of very large dimensions, in various parts of the world. There is in China, for instance, a great canal, 900 miles in length and 200 feet broad, which is supposed to have been made 800 years ago. The advantages of canals did not escape the attention of the Egyptians, Greeks and Romans. We read of very early attempts to cut through isthmuses, in order to form a water communication between regions where other carriage would be long and difficult. It appears to be admitted that canals connecting the Red Sea with the Mediterranean existed some centuries before the Christian era, and to cut the Isthmus of Corinth by a waterway was a cherished project with several Roman Emperors, and now it appears that in this nineteenth century this project will shortly be realized. But as the canal-lock is but a comparatively modern invention, dating only from the fourteenth century, and first used in Holland, all the canals anterior to that period had to be designed as level cuts, a restriction which greatly increased the difficulties of the problem. Canals were in use in various parts of Europe, particularly in Holland and France, long before any were constructed in England, as, for example, the Languedoc Canal, which, by a cut of 150 miles, connects the Bay of Biscay with the Mediterranean. It is 60 feet broad, and attains, at its highest level, an elevation of 600 feet above the sea. The canal system in England was first introduced in the middle of the eighteenth century, and soon afterwards, the Duke of Bridgewater engaged the famous Brindley to construct a canal, connecting his collieries at Worsley with Manchester, about seven miles distant, and afterwards extended his scheme, so as to open up a more direct water communication between Manchester and Liverpool. Before the making of this canal, the cost of the carriage of goods between these towns had been forty shillings per ton by land, and twelve shillings by water. After that, they were conveyed with regularity for six shillings per ton. The system was soon extended, so as to connect the Trent with the Mersey, and the boldness of both the projectors and their engineer in carrying out this scheme is memorable in the history of such undertakings. Brindley was equal to the task of coping with the difficulty of carrying his canal over what had hitherto been supposed an insuperable obstacle, for he pierced Harecastle Hill with a tunnel more than a mile and a half in length—a then unheard of piece of engineering—to say nothing of several shorter tunnels, many aqueducts, and scores of locks. The Duke of Bridgewater, who at one period had been unable to raise £500 on his own bond for the prosecution of his scheme, died in 1803, in receipt of a princely income from the profits of his useful undertaking. For its creation, he had, however, denied himself the present enjoyments of his patrimonial revenue, by reducing his expenses at one period to the modest sum of £400 per annum. Before his death, the Duke, for taxation purposes, estimated his income at £110,000 per annum. Before the railway system was fully established a network of canals had united the most populous places in England, the total length of the waterways being not much less than two thousand miles. With the rise of railways the importance of canals as channels for the conveyance of merchandise declined. But, nevertheless, in consequence of the continued increase of traffic and the great cheapness with which goods can be carried by water, canals are often able to compete with railways in the carriage of bulky or heavy goods when speed of transit is not an object. The English canals have, therefore, never been disused or abandoned, notwithstanding the ubiquitous ramifications of the railway lines. Nay, the value of the Bridgewater Canal system, about to be superseded so far as concerns the communication between Liverpool and Manchester by the greater scheme we have presently to describe, is such that £1,710,000 is now required for its purchase; and that is the value in spite of four lines of railway connecting those great towns, and all competing for the carriage of goods. In these canals, designed for inland communication only, the navigation is confined to boats or barges of very insignificant dimensions compared with the sea-going ships that some great modern canals are constructed to receive.

To the present century belongs the famous “Caledonian Canal,” as the waterway is often called that extends in a straight line for more than 60 miles across Scotland, in north-east and south-west directions. The canal work here was commenced in 1802, under the direction of Telford, and though it was opened for traffic in 1822, the work as it now exists was not completed until 1847. But the length of the actual canal construction in this case did not much exceed 23 miles, for a natural waterway, navigable for ships of any burden, is formed by the series of narrow lakes that fill what is called the “Great Glen of the Highlands.” This glen has many of the characteristics of a great artificial ditch: its highest point is only 90 feet above the tide level in Loch Linnhe; a circumstance not a little remarkable in so mountainous a country. What is also remarkable is the great depth of these lakes, which in some places exceeds 900 feet. The banks also are generally very steep, and indeed at one time it was impracticable to pass along the shores of Loch Ness, the longest of the lakes. But there are now good roads along both banks. Although the ground traversed by the artificial channels of the Caledonian Canal is chiefly alluvial, the cost of the undertaking proved to be great, amounting, it is said, to about one and a quarter million pounds sterling. Indeed, had it not been for the introduction of steam navigation before the completion of the work, and the consequent increase and facility of water conveyance, it is doubtful whether the utility of this canal would have been commensurate with its cost, or its receipts have made any profit for its promoters. By the Caledonian Canal large steamers and other vessels may pass from sea to sea, and in the summer time the steamers that traverse it are crowded with tourists attracted by the magnificent scenery it presents throughout the greater part of its length.

But whatever had previously been done in canal construction was surpassed in enterprise and importance by Lesseps’ great work in Egypt.

THE SUEZ CANAL.

As we have already seen, the idea of opening a waterway between the Red Sea and the Mediterranean is by no means a product of the present century. The ancient Egyptians do not appear to have cut directly through the Isthmus, but Herodotus describes a canal made by Necho about the year 600 B.C., from Suez through the Bitter Lakes to Lake Timsah and then westward to Bubastis on the Nile. He mentions certain water gates, and states that vessels took four days in sailing through. This canal became silted up with sand ages ago, but it was cleared out again and re-opened in the seventh century of our era by the Caliph Omar, and traces of it are still visible. According to some recent discoveries in the chief archives of Venice, as early as the end of the fifteenth century, when Vasco da Gama had discovered the Cape of Good Hope, and the Portuguese took that new route to India, hitherto the exclusive property of the Venetian and Genoese merchants, a re-cutting of the Isthmus of Suez was thought of. Plans were prepared and embassies sent to Egypt for paving the way for the accomplishment of this great enterprise, which, it is said, was only foiled by the persistent opposition of some patricians, who were probably bribed by foreign gold to prevent the execution of the plan. One of our Elizabethan poets, Christopher Marlowe, appears, in the following lines, to have anticipated M. de Lesseps:—

“Thence marched I into Egypt and Arabia,
And here, not far from Alexandria,
Whereat the Terrene and the Red Sea meet,
Being distant less than full a hundred leagues.
I meant to cut a channel to them both,
That men might quickly sail to India.”

For at that period travellers going to India in the famous sailing ships, called “East Indiamen,” were obliged to sail round the Cape of Good Hope and pass from the Southern to the Indian Ocean. The reader who wishes to understand the importance of the Suez Canal should look at the map of the Eastern Hemisphere, where he will have no difficulty in finding the position of the vast continent of Africa, which is washed on the north by the Mediterranean Sea, on the west by the Atlantic, on the south by the Southern Ocean, and on the east and north-east by the Indian Ocean and the Red Sea. If he now traces the waterway round Africa, on coming to the head of the Red Sea he will find the only interruption of the oceanic continuity in the narrow neck of land called the Isthmus of Suez. But for this, ships might long ago have made complete circuits round this vast, and, even as yet, but partially explored continent. The circuit would, indeed, be a great one of some 15,000 miles; but the barrier that the Isthmus presented to inter-oceanic communication between the eastern and the western worlds was a piece of physical geography which has undoubtedly been a most important factor in determining the course of history. It has been said that had there existed at Suez a strait like that of Gibraltar or that of Messina, instead of a sandy isthmus, the achievements of Diaz, Vasco da Gama, and Columbus would have lost much of their significance; but the advantages to the world’s commerce would have been incalculable, and the progress of the race might have been more rapid.

The Emperor Napoleon I. had the idea of restoring the old canal; but it was only when steam navigation had taken its place on the seas that the scheme was looked upon as offering any chance of financial success. But General Chesney, who made some surveys for the French Government in 1830, had come to the conclusion that there was a considerable difference of level between the two seas—a difference, he calculated, of about 30 feet. The existence of such a state of things would, of course, have been very unfavourable for the undertaking; but the General’s supposition was soon proved to have been erroneous.

The suggestion of carrying out the project of constructing a ship canal through the Isthmus was seriously revived by PÈre Enfantin, the St. Simonian, in the year 1833. He then induced M. Ferdinand Lesseps, the French vice-consul, and Mehemet Ali, the Pasha of Egypt, to take some practical measures towards its accomplishment. Surveys were made, but owing to the breaking out of a plague, and to other causes, not much more was heard of the scheme till 1845. In 1846 La SociÉtÉ d’Etude du Canal de Suez was formed, and among those who turned their attention to the subject was Robert Stephenson. His report was wholly unfavourable to the enterprise. He recommended the construction of a railway through Egypt, and a line was accordingly made between Alexandria and Suez. But, notwithstanding the opinion of Mr. Stephenson, M. Lesseps persevered with wonderful energy, believing, on the report of other engineers, that the scheme could be successfully carried out. It is right, however, to state that Mr. Stephenson did not say it was impossible to complete the Suez Canal—he merely gave it as his opinion that the cost of making the canal, and keeping it in a proper state for navigation, would be so great that the scheme would not pay. However, in 1854, the Viceroy of Egypt signed the concession, and in 1860 the work was actually commenced, but not on a plan that was advocated by the English engineers of making the canal 25 feet above the sea level. There were also some political and financial difficulties to be overcome. The Suez Canal Company, it was said, had expended twelve millions of money in what was considered to be chiefly shifting sands.

Fig. 123.The Sand-Glass.

When the Suez Canal was projected, many prophesied evil to the undertaking, from the sand of the Desert being drifted by the wind into the canal, and others were apprehensive that where the canal was cut through the sand, the bottom would be pushed up by the pressure of the banks. They imagined that the sand would behave exactly like the ooze of a soft peat-bog, through which, when a trench has been cut, the bottom of the trench soon rises, for the soft matter has virtually the properties of a liquid: it acts, in fact, exactly like very thick treacle. Sand, however, is not possessed of liquid properties; it has a definite angle of repose, which is not the case with thin bog. This behaviour of sand is familiarly illustrated in the sand-glass, which the diagram Fig. 123, will recall to mind. It may be observed that the sand falling in a slender stream from the upper compartment is in the lower one heaped up in a little mound, the sides of which preserve a nearly constant inclination of about 30°. In this property it is distinctly different from peat-bog or such-like material, which has no definite angle of repose. It need hardly be said that all apprehensions as to the safety of the canal from the causes here alluded to have proved unfounded.

But if some English engineers appeared to oppose the project, another eminent one, Mr. Hawkshaw, certainly helped it on at a moment when the Viceroy of Egypt was losing confidence; and, had his opinion been adverse to the project reported upon, the Viceroy would certainly not have taken upon himself additional liability in connection with the undertaking, and the money expended up to that date would have been represented only by some huge mounds of sand and many shiploads of artificial stone, thrown into the bottom of the sea to make the harbour of Port SaÏd. And that M. Lesseps appreciated the good offices of Mr. Hawkshaw is shown from the fact that, when he introduced that engineer to various distinguished persons, on the occasion of the opening of the canal, he said, “This is the gentleman to whom I owe the canal.” It cannot, therefore, be said of the English nation that they were jealous of the peaceful work of their French neighbours, or opposed it in any other sense but as a “non-paying” and apparently unprofitable scheme.

The Canal was opened in great state by Napoleon III.’s Empress EugÉnie, in November, 1869, when a fleet of fifty vessels passed through, and the fact was thus officially announced in Paris:—“The canal has been traversed from end to end without hindrance, and the Imperial yacht, Aigle, after a splendid passage, now lies at her moorings in the Red Sea.

“Thus are realized the hopes which were entertained of this great undertaking—the joining of the two seas.

“The Government of the Emperor cannot but look with satisfaction upon the success of an enterprise which it has never ceased to encourage. A work like this, successfully accomplished in the face of so many obstacles, does honour to the energetic initiative of the French mind, and is a testimony to the progress of modern science.”

An Imperial decree was then issued, dated the 19th of November, appointing M. de Lesseps to the rank of Grand Cross of the Legion of Honour, in consideration of his services in piercing the Isthmus of Suez.

The Suez Canal is 88 geographical, or about 100 statute miles long: its average width is 25 yards, and the minimum depth, 26 feet. At intervals of five or six miles, the canal is widened, for a short space, to 50 yards, forming thus sidings (gares) where only vessels can pass each other. At these, therefore, a ship has often to wait until a file of perhaps twenty steamers, coming the other way, has passed. Occasionally a ship gets across, or “touches,” and then the canal is blocked for hours. So much inconvenience has been found from the restricted dimensions of the work, that in 1886 it was proposed to widen the canal, or, alternatively, to construct a second canal, and use the two like the lines of a railway, so that vessels would never have occasion to pass each other. The amount of traffic is very large, and has been steadily increasing. Thus, in 1874, the tonnage of the vessels passing through was 5,794,400 tons; in 1880, the tonnage was 8,183,313, and the receipts of the Company amounted to £2,309,218. In 1875, the British Government purchased, from the Khedive, £4,000,000 worth of shares.

Fig. 124.A Group of Egyptian Fellahs, and their Wives.

The Suez Canal is not so much a triumph of engineering as a monument of successful enterprise and determination on the part of its great promoter, M. Lesseps, in the face of great difficulties. According to the original programme, the canal was to have been constructed by forced labour, supplied by the Viceroy. The unhappy peasantry of the country, called “fellahs,” were compelled to give their labour for a miserable pittance of rice. No doubt, in ancient times, when forced labour was in use, every peasant might cheerfully work, because it was for the general benefit to bring sweet water from the Nile to other dry and thirsty places in Egypt; but to be obliged to work at a waterway of salt, which was only to be of use to foreigners who passed through the country, could not be expected of human beings, and therefore the carrying out of the work was not unaccompanied by cruelties of the nature attending slave labour in other lands. This was one of the reasons why the late Lord Palmerston opposed the canal scheme, for the kind hearted statesman bore in mind the loss of health and life occasioned to poor Egyptians by this mode of labour, and the more so because it had been originally proposed that one of the conditions on which the French Company was to take up the project should be the execution of the work by free labour. In consequence, no doubt, of representations from free countries, the Porte was induced to put a veto on the employment of forced labour, and everyone thought that this would be the deathblow to the completion of the canal: but M. Lesseps did not give way to despair, and he since stated that if he had depended on the labours of the fellahs only, the difficulties of the work never could have been surmounted; and that, in fact, the successful prosecution of the work was owing to his having turned his attention to the mechanical contrivances used for dredging on the Thames and the Clyde, from which he obtained better results in half the time and at half the cost.

Fig. 125.Dredges and Elevators at Work.

The dredges used in the construction of the canal were of a new description. They were wonderful mechanical contrivances, and but for them the canal would not have been finished. They were not the contrivance of M. Lesseps, but of one of the contractors, a distinguished engineer, who received his technical education in France but his practical experience in England. The use of the dredging machines was prepared for by digging out a rough trough by spade work, and as soon as it had been dug to the depth of from six feet to twelve feet, the water was let in. After the water had been let in, the steam dredges were floated down the stream, moored along the bank, and set to work. The dredges were of two kinds. The great couloirs consisted of a long, broad, flat bottomed barge, on which stood a huge framework of wood, supporting an endless chain of heavy iron buckets. The chain was turned by steam, and the height of the axle was shifted from time to time, so that the empty buckets, as they revolved round and round, should always strike the bottom of the canal at a fixed angle. As they were dragged over the soil they scooped up a quantity of mud and sand and water, and as each bucket reached its highest point in the round, it discharged its contents into a long iron pipe which ran out at right angles to the barge. The further extremity of this pipe stretched for some yards beyond the bank of the canal, and therefore, when the dredging was going on, there was a constant stream of liquid mud pouring from the pipe’s mouth upon the shore, and thus raising the height of the embankment. When the hollow scooped out by the buckets had reached the required depth, the dredge was moved to another place, and the same process was repeated over and over again. These stationary dredges, however, though very effective, required much time in moving, and the lighter work of the canal was chiefly effected by movable dredges of a smaller size. These machines were of the same construction as those described; the only difference was that the mud raised by their agency was not poured directly on shore by pipes attached to the dredges, but was emptied in the first instance into large barges moored alongside the dredge. These barges were divided into compartments, each of which contained a railway truck, and when the barge was filled it steered away to the bank, where an elevator was fixed. The trucks, filled with mud were raised by a crane worked by steam power, and placed upon inclined rails, attached to the elevator, which sloped upwards at an angle of 45 degrees towards the bank. They were then drawn up the rails by an endless rope, and as each truck reached the end of the rails its side fell open, the mud was shot out upon the bank, and the empty truck returned by another set of rails to the platform on which the elevator was placed, and was thence lowered into the barge to which it belonged. As the elevator could unload and re-load a barge much faster than the dredges could fill it with mud, each elevator was fed by half a dozen dredges, and thus the mud raised from the canal by several dredges was carted away without difficulty at one and the same time. As these floating dredges were much easier to shift than those encumbered by the long couloir pipes, the work of excavating the bed went on much more rapidly. But in places where there was any great mass of earth or sand to be removed, the large couloirs could scoop out a given volume in a shorter time.

The traveller who wishes to see the canal should go to France, and, embarking at the port of Marseilles, cross the Mediterranean Sea, and steam to Port SaÏd, which is about 150 miles east of the port of Alexandria, where the isthmus is crossed by the railroad, and is used by travellers to India, being known as the “overland route.” And this railway conveys the mail to and from India, thus saving the great sea voyage round Africa and the Cape of Good Hope. Nevertheless, it involves two transhipments—from the steamer to the rail at Alexandria, and from the railway to the steamer at Suez.

Fig. 127.Port SaÏd, the Mediterranean entrance to the Suez Canal.

Let us notice in order the places passed by the traveller in going from Port SaÏd to Suez and the Red Sea. The arrow (Fig. 126) points in the direction of the compass, and shows that the canal runs very nearly from north to south. Port SaÏd is the little town at the northern or Mediterranean entrance to the canal, situated on the flat sands at the entrance of the canal, and is built chiefly of wood, with straight wide streets and houses, and although it now contains several thousand inhabitants, before the making of the canal was begun one hundred people could hardly have been got together. The town contains nothing deserving of notice, and has a striking resemblance to the newly settled cities of America. But in it reside agents who represent numerous varied interests—administrative, financial, mercantile and political. It is provided with docks, basins, quays and warehouses, and has a harbour stretching out a couple of miles or so into the sea, for to that distance two piers, or rather breakwaters, run out.

Fig. 128 shows these two converging breakwaters, which have been built out into the Mediterranean from the coast, the larger and more westerly one being one mile and a half long, the shorter about a mile and a quarter, and the distances between the two lighthouses erected on the extremities of the breakwater being half a mile.

The piers are made of concrete which was cast in blocks weighing 10 tons each. This composition has of late years been greatly approved by engineers where stone cannot be procured. The sea-face of the great canal in Holland is composed of a similar artificial stone, and it is found to bear the wear and tear of the waves almost, if not quite, as well as ordinary stone. It is stated that 25,000 blocks, each weighing 10 tons, were used. They were not laid with the regularity of ordinary masonry, but had been dropped from large barges, so that they presented a very rugged and uneven appearance (Fig. 129); but the object of throwing out these great bulwarks is for the purpose of preventing the sand brought down by the Nile silting in and closing up the canal. Along the western pier there is, from this cause, a constant settlement of sand, which was partially washed through the interstices left between the blocks of artificial stone, and might have given some trouble by forming sandbanks in the harbour; but this was prevented by the introduction of smaller stones, which could readily be carried out in boats at the low tide.

Fig. 128.Bird’s-eye View of Port SaÏd.

Beginning with the Mediterranean Sea and Port SaÏd, there is a run of 28 miles to Kantara, through Lake Menzaleh. Although called a lake, it is, in truth, nothing but a shallow lagoon or swamp, in which water-fowl of all kinds are very abundant, the great flocks of white pelicans and pink flamingoes being especially striking. The waters of this lagoon cover lands that once were fertile, and the salt sea-sands doubtless conceal the remains of many an ancient town.

Fig. 129.One of the Breakwaters at Port SaÏd.

Of all portions of the undertaking, this one, M. Lesseps states, was the most arduous and difficult, though, at the time, it attracted the least attention. A trough had to be dredged out of the bed of the shallow lagoon, and on either side of this hollowed out space high sandbanks had to be erected, and the difficulty of making a solid foundation for these sand banks was found to be extreme. The difficulty, however, was surmounted, and such is the excellence of the work, that the water neither leaks out, nor does any of the brackish water of the lagoon infiltrate and undermine the great embankments.

Fig. 130.Lake Timsah and IsmaÏlia.

At Kantara, the canal crosses the track of the highway between Cairo and Syria—a floating bridge carries the caravans across; and near this spot is stationed an Egyptian man-of-war, which supplies the police for the proper watch and ward of the canal. From Kantara to El Fendane is a distance of 15 miles—that is to say, to the southern extremity of Lake Ballah, where the canal still passes through sand embankments, raised within a mere. The lake is, however, almost dried up, and therefore the difficulties which had to be surmounted at Lake Menzaleh were not felt here.

The traveller may now be supposed to have arrived at Lake Timsah, where, no doubt, in the days of the Pharaohs, a lake existed. When taken in hand by M. Lesseps, it was a barren, sandy hollow, containing a few shallow pools, through which a man could easily wade, but now it is filled with the waters of the Mediterranean Sea. It is a pretty, inland, salt water lake, about three miles in width. On the northern shore stands the town, or, rather, small settlement of IsmaÏlia, which is, in fact, the “half way house” where most of the officials of the Suez Canal Company resided, as they could get to either end of the canal with greater facility, or to Cairo by the railroad, which comes to this point, and continues, with the canal, to Suez.

Fig. 131.Railway Station at IsmaÏlia.

When the canal was opened, in November, 1869, IsmaÏlia was the scene of the most brilliant part of the opening ceremony, in which the French Empress EugÉnie, the Empress of Austria, the Crown Prince of Prussia, and other distinguished personages took share. The Khedive built himself a summer palace, and M. Lesseps erected a villa, and the town was most artistically laid out, with every prospect of becoming a flourishing place. But the drainage had been so entirely overlooked, that it is said the sewage found its only outlet in the fresh water canal; and the consequence was fever broke out and so infected the town, that it was soon almost quite deserted. In 1882, IsmaÏlia was once more the scene of bustle and activity, for here was the base of Sir Garnet Wolseley’s operations in his brilliant campaign against Arabi. The British Navy entered the canal, and took possession of IsmaÏlia, where the army and the military stores were rapidly concentrated. From this place, Sir Garnet advanced along the route of the railway and the Sweet Water Canal, and, after storming the lines of Tel-el-Kebir, occupied Cairo, without further resistance, after a campaign of only three weeks’ duration.

From Lake Timsah to the Bitter Lakes the canal again passes for eight miles or so through the desert, where, by partial excavations by hand labour and subsequent flooding to admit the dredges, it was considered that a sufficiently deep channel could be made. The couloirs were set to work, when suddenly “a lion arose in their path” in the shape of a great rock, about 80 feet in length, and lying 12 feet only below the surface, and right in the middle of the main channel. If anything could show the indomitable energy of M. Lesseps it was his courage in dealing with this difficulty, and at a time when a few months only could elapse before the advertised day of the opening. He attacked the sunken rock with gunpowder. A large raft, or floor, supported on barges, was moored over the sunken rock, and from this men, armed with long poles shod with steel, drilled numerous holes, into which charges of gunpowder were placed, and fired in the usual manner by the electric battery. This temporary obstruction occurred opposite to the landing place at SÉrÁpeum.

Fig. 132.The Viceroy of Egypt cutting the last embankment of the Reservoir of the Plain of Suez, to unite the two seas—the Mediterranean and the Red Sea.

Passing by SÉrÁpeum, the traveller arrives at a vast expanse of water called the “Bitter Lakes,” because the dry sandy hollow formerly contained a marsh, or mere, of very brackish water. The possibility of keeping this great area filled with sea water had been denied by the opponents of the canal, who said the water would sink into the sand or be evaporated by the intense heat of the sun; but none of these prognostications have been verified, and it is now a great inland sea, far surpassing Lake Timsah, being 25 miles long and from six to seven miles wide. The only difficulty in filling this enormous natural basin arose from the rapidity and force with which the waters flowed in. This was done when the water at Suez was at low tide, and then subsequently the Red Sea was allowed to flow in. Though the expanse of water in the Bitter Lakes is great enough, the available channel is still narrow. But the steamers can proceed at full speed, as here there are no banks to be washed away.

Since the two seas have joined their waters, a strong current has set in from south to north, but there is no eddy or fall at the place where the waters meet. The tide runs up the canal with great force, and there is a difference of six or seven feet between high and low water: but the tide does not extend beyond the Bitter Lakes, where it is gradually diffused and lost. The colour of the current of water from Suez is said to be green, whilst that portion fed by the Mediterranean is blue. Since the Bitter Lakes have been filled the mean temperature of the districts on the banks has fallen 5° Centigrade. It is also stated that, although the canal swarms with sea fish they keep to their respective ends of the canal, as if the Mediterranean fish would not consort with those of the Red Sea, or, rather, make themselves at home in strange waters. There is also, perhaps, another cause, and that is the very bitter nature of the water at the northern end of the Bitter Lakes, which acts as a natural barrier, through which the fish may decline to pass.

The bed of the Bitter Lakes is the only portion of the canal’s course in which it was not necessary to make a cutting. Buoys are laid down to mark the best channel, but such is the width and depth of the water that vessels need not exactly keep within them. Quitting the Bitter Lakes we again enter the canal proper. In order to reach the vast docks which the Suez Canal Company has constructed on the western coast of the Red Sea, the canal is now quitted, and the vessel crosses the neck of the Red Sea. The Cairo and Alexandria Railway has been extended two miles, and is carried through the sea on an embankment, which lands the train close to the docks and quays of the canal, so that passengers by the overland route are able to embark from the train on board the steamer, and thus escape the troublesome transhipment of themselves and luggage.

THE MANCHESTER SHIP CANAL.

The project of constructing a ship canal to connect Manchester with the sea appears to have been started just before the railway era, but it was then abandoned, as the opening of the Liverpool and Manchester Canal brought about an immediate reduction in the rates of carriage. Perhaps it was the success of the Suez Canal which caused the revival of this scheme, in 1880, combined with the depression of the cotton trade at that period, when the Liverpool dock dues and the comparatively high railway rates proved a heavier tax than usual on the great Lancashire industry. The first definite steps were taken two years afterwards, when two plans were submitted for the selection of a committee. One scheme proposed to construct the canal without any locks; but, as Manchester is 60 feet above the sea level, there would, it was felt, be certain inconveniences in loading or unloading ships in a deep depression. The other plan was submitted by Mr. Leader Williams, a well known canal engineer, who proposed to take the canal from Runcorn, a distance of 20 miles, and making use of locks. When Parliament was applied to for powers authorizing the prosecution of the enterprise, there was, of course, much opposition offered by the various interests involved, and the inquires before the Committees of each House of Parliament were unusually protracted, for they extended in all to 175 days, and the cost to the promoters is said to have amounted to £150,000. Then, when the Bill had passed, it was found that the capital (£8,000,000) could not be raised owing to the financial depression, and partly also to some want of confidence in the soundness of the undertaking on the part of the Lancashire capitalists. But the promoters submitted the whole scheme to a representative committee, who should consider any possible objections. This committee reported (after sitting almost daily for five weeks) upon every point, and were unanimous in pronouncing the undertaking to be perfectly practicable and commercially sound. After this there was no difficulty in raising the required capital, which was subscribed by corporate bodies as well as private persons. The contract was let for £5,750,000, and the work was commenced in November, 1887, the contractor undertaking to have the canal completed and ready for traffic by January 1st, 1892.

Fig. 133.Western Portion.

Fig. 134.Eastern Portion.
Figs. 133 and 134.Map of the Manchester Ship Canal.

The Manchester Docks of this canal will cover an area of nearly 200 acres at the south-western suburb of that city, and from there the canal traverses the Valley of the Irwell, following, indeed, the general course of the river, but not its windings, so that the bed of the river is, in the distance of eight miles, or down to its junction with the Mersey, repeatedly crossed by the line of the canal. From the confluence of the rivers, the canal traverses the Valley of the Mersey, for this is the name retained by the combined streams. The course of the river, in its progress towards the sea, now makes wider bends, but the canal proceeds, by a slight and nearly uniform curve, to Latchford, near Warrington, passing to the south of which last named place it follows a straight line to Runcorn, which is at a distance of 23 miles from Manchester. Here it reaches what is now the estuary of the Mersey, but the embankments are continued along the southern shore to Eastham, where the terminal locks are placed. In this part of the canal, the engineer had difficulties to overcome of a different nature from those encountered in the upper part, where it was chiefly a matter of cutting across the ground intervening between the bends of the river, so as to form for its waters a new and direct channel everywhere of the requisite breadth and depth. But when Runcorn has been passed, and Weston Point rounded, there is the mouth of the River Weaver to be crossed, and this is marked by a great expanse of loose and shifting mud. Other affluents of the Mersey are dealt with by means of sluices, and in one instance the waters of a river are actually carried beneath the course of the canal by conduits of 12 feet in diameter. The total length of the canal from Manchester to the tidal locks at Eastham is 35 miles.

Fig. 135.A Cutting for the Manchester Ship Canal.

Fig. 136.Blasting Rocks for the Manchester Ship Canal.

The minimum width of the canal at the bottom is 120 feet, its depth 26 feet. But for several miles below Manchester this width will be increased, so that ships may be moored along the sides, and yet sufficient space left for the up and down lines of traffic in the middle. In this way, works and manufactories on the banks will be able to load and unload their cargoes at their own doors, and it may be expected that the advantages so offered will cause the banks of the canal to be much in request for the sites of works of all kinds. At the several places where the locks are placed there will be a smaller and a larger one, side by side, so that water shall not be needlessly used in passing a moderate sized vessel through the greater locks. As these last are 550 feet long and 60 feet wide, they are capable of receiving the largest ships, whilst the smaller locks are 300 feet long and 40 feet wide. Again, both the larger and the smaller are provided with gates in the middle, so that only half their length may be used when that is found sufficient. Coming down the canal from Manchester, the first set of locks will be at Barton, about three miles distance, just below the place where the Bridgewater Canal is carried across the Irwell, which is now to become the ship canal, by means of the aqueduct of 1760, by which Brindley became so famous. There is a story told about Brindley being desirous of satisfying the duke about the practicability of his plan, and requesting the confirmatory opinion of another engineer. When, however, this gentleman was taken to the place where it was proposed to construct the aqueduct, he shook his head, and said that he had often heard of castles in the air, but had never before been shown where any of them were to be erected. This aqueduct is about 600 feet long, and the central one of its three arches spans the river at a height of nearly 40 feet above the water. But the Manchester Ship Canal requires a clear headway of 75 feet, and Mr. Williams is going to replace the fixed stone structure by a swinging aqueduct, or trough of iron, which can be turned round, so as to give a clear passage for ships in his canal. This trough, or great iron box, will have gates at each end, and gates will be provided in the aqueduct at each side, so that no water will be lost when the water bridge is turned aside. But more than this; hydraulic lifts have been designed, so that, in a few minutes, vessels can be lowered from the Bridgewater Canal into the Manchester Canal, or raised from the latter into the former while still floating in water. The supply of water for the canal will be ample, as it has the rivers Irwell, Mersey and Bollin, with their tributary streams, to draw from. It should be mentioned that the terminal locks at Eastham will be of somewhat larger dimensions than those already referred to, and will be three in number. The largest, which is on the south or landward side, will be 600 feet by 80 feet, the middle one 350 feet by 50 feet, and the smallest one 150 feet by 30 feet. These three locks will be separated by concrete piers 30 feet wide, on which will be placed the hydraulic machinery for opening and closing the gates. Besides the ordinary gates, there will be provided for each lock at Eastham an outer pair of storm-gates that will be closed only in rough weather. These gates will shut from the outside against the lock sills, and, by resisting the force of wind and waves, will protect the ordinary tidal gates from being forced open. The lock gates throughout will be made of a wood obtained from British Guiana, and known as greenheart. This timber is the product of a large tree (Nectandra Rodioei) belonging to the laurel family. It is a very heavy and close grained wood, the strength and endurance of which have been proved many years ago by its use in ship-building, etc., and some of the logs imported for the canal are remarkably fine specimens, being 22 inches square and 60 feet long. A pair of the largest gates weigh about 500 tons. The gates of the tidal locks at Eastham will all be open for half the time of each tide, when there will be a depth of water, above the sills, greater by 11 feet than that of any dock in Liverpool or Birkenhead.

Fig. 137.Manchester Ship Canal Works, Runcorn.

The way in which the difficulty is overcome of crossing the several busy lines of railway that intersect the course of the new canal, so that their traffic shall not be impeded, is one of special interest in this bold scheme. The London and North Western Railway crosses the Mersey at Runcorn by a bridge that leaves a clear headway of 75 feet at high water, and it was determined that this headway should be maintained in the bridges over the canal. The use of swing bridges on lines of railway over which trains are constantly passing being out of the question, it is necessary that the railways be carried over the canal at the required height. It is accordingly laid down in the Act of Parliament that before the Canal Company can cut the existing lines of railway it shall construct permanent bridges, and carry over them lines rising by gradients not exceeding 1 in 135, and not only so, but these deviation lines must be previously given up to the several railway companies for six months to be tried experimentally in that period for goods traffic. The cost of constructing these deviation lines, which, in all, will not be far short of 12 miles of new railway, will not be much less than £500,000. The traffic of the canal will probably have great feeders at certain points in the other canals and the railway lines that reach it. For instance, the Bridgewater Canal, now incorporated with the greater undertaking, will bring traffic from the Staffordshire potteries, the river Weaver brings salt laden barges from Cheshire, and at other points the railways will bring the produce of the excellent coal fields of South Yorkshire and South Lancashire, which will be automatically transferred from the waggons into ocean going steamships.

Fig. 137a.The French Steam Navvy.

Fig. 137b.—The English Steam Navvy.

Though the general notion of the construction of the canal as a deep, wide trench, or cutting following the course shown on the map, is sufficiently simple, the operation of carrying this into practice involves the exercise of great skill and ingenuity in dealing with mechanical obstacles. Man’s operations in the world consist but in changing the position of masses of matter; and the properties of matter—its inertia, cohesion, gravitation, etc., are the forces that oppose his efforts. The quantity of matter to be shifted in excavating this trench of thirty-five miles long across the country was no less than sixty millions of tons. The number of “navvies” employed at one time has been 15,000; but even this army of workmen would have made but slow progress with a cutting of this magnitude, had not the “strong shouldered steam” been also called into operation for scooping out the soil. The illustrations (Figs. 137a and #137b:fig137b) will show the arrangement of two forms of “steam navvies” that were much used on the works. One (Fig. 137a) is similar to the dredgers used for clearing mud out of rivers and canals: it consists of a series of scoops, or buckets, mounted on an endless chain, so as to scrape the material from an inclined embankment and tip it into waggons for removal. The other (Fig. 137b) may be compared to a gigantic ladle made to scrape against the face of a cutting in rising, and filling each time its bucket with nearly a ton of the material. It is most interesting to witness the perfect control which the man at the levers exercises over this machine, the movements of which he directs with as much precision as if he were handling a spoon. One of these steam navvies is able to fill 600 waggons or more—that is, to remove 3,000 tons of material—in one day; and as many as eighty of them have been simultaneously used on the Canal works. The value of the plant employed by the contractor is estimated at £700,000, and the length of temporary railway lines (see Fig. 137), for transport of the “spoil,” etc., is said to exceed 200 miles. There is a main line running through from one end of the canal to the other, and known to the workmen as the “Overland Route.” From this diverge numerous branches, some to the bottom of the excavations in progress, others to embankments down which is tipped out the “spoil,” as the dug out material is called; while others connecting with brickfields and quarries, or with existing canals and railway lines, serve to bring supplies of the materials used in the constructions. Some 150 locomotives are constantly at work on these temporary lines, and the coal consumed by them, and by the steam navvies, steam cranes, pumping engines, etc., is equivalent to about two train loads every day.

Though the Manchester Ship Canal is to be nearly twice as wide as the Suez Canal, its width for some miles below Manchester will be still greater, for there the banks will form long continuous wharves for the accommodation of the works and factories that are certain to be attracted to the spot. Indeed, so obvious are the advantages of ocean shipment, and so extensive the industries of South Lancashire, that it is not improbable the whole course of the canal may, in process of time, be lined with wharves, and the two great cities of Manchester and Liverpool may be united by a continuous track of dense population. Be that as it may, there seems every reason to believe that the undertaking will be a financial success. Calculation has shown that if the cotton alone that enters and leaves Manchester were carried by the canal at half the rates charged by the railways, there would result not only an annual saving of £456,000 to the cotton trade, but a clear profit to the canal company sufficient to pay more than 3 per cent. interest on its own capital. And, again, the railway and other local interests that have hitherto been opposed to this great enterprise can hardly fail to be in the long run benefited by the enlarged prosperity and increased general trade and manufactures it will develop. So that it will presently be found that there is room enough and work enough for both canal and railways.

The Manchester Ship Canal, so far from having been ready for traffic on the 1st January, 1892, was not completed until the end of 1893, and it was only on the 16th December, 1893, that the directors and their friends made the trial trip throughout its entire length, accomplishing the distance of 35½ miles in 5½ hours. The total cost of the canal was greatly in excess of the estimates, which placed it at eight million pounds, as fifteen millions is the sum actually expended upon it. With such a vast capital expenditure, it may be some time before the ordinary shareholders can look for dividends, especially as there has not been any sudden rush of traffic, such as many sanguine people expected. On the other hand, traffic is continuously and steadily increasing, and there is reason to believe that this great work will ultimately prove a commercial, as it has an engineering, success.

Fig. 137c.Sketch Map of The North Sea Canal.

THE NORTH SEA CANAL.

Like several other canals for sea going ships this last addition to the achievements of modern engineering is but the realisation of a project conceived at a long past period. The idea of a canal to connect the Baltic and the North Sea dates back into the Middle Ages, and indeed a short canal was constructed in 1389, which by uniting two secondary streams of the peninsula really did provide a waterway between the two seas. The inefficiency of this means of communication may be inferred from the fact of there having been proposed since that period no fewer than sixteen schemes of canalisation between these two seas, of which the recently completed North Sea Canal is the sixteenth, and it need hardly be said the greatest, so that in comparison with it the rest vanish into insignificance. The canal was commenced in 1887, and on the 20th of June, 1895, it was opened by the reigning Emperor of Germany, William II., with a very imposing naval pageant in which nearly a hundred ships of war from the great navies of the world took part. A glance at the accompanying sketch-map will show the great importance of this canal as a highway of commerce. The entrance to the Baltic has hitherto been round the peninsula of Denmark and through the narrow “belts” and “sounds” that divide the Danish Islands, a course beset with imminent perils to navigators, for the channels abound in rocks and dangerous reefs, to say nothing about the frequent storms and the impediments of ice floes. Yet as many as 35,000 vessels have lately had to take that course annually, these representing a total tonnage of no less than 20,000,000 tons. The figures speak for the magnitude of the Baltic shipping intercourse with the rest of the world; while the losses incurred in traversing these forbidding waters may be gathered from the statement that since 1858, nearly 3000 ships have been wrecked in them, and a greater number much damaged. Indeed, for large vessels, there is hardly a more dangerous piece of navigation in all Europe. The importance of this canal must not therefore be estimated solely by the saving of length in ships’ course, though that is great, as the map shows.

The North Sea Canal is 61 miles long, 200 ft. wide at the surface, 85 ft. wide at the bottom, and it will admit of vessels of 10,000 tons register passing through, the average time of transit being about twelve hours. The estimated cost of this undertaking was nearly eight and a quarter million pounds sterling, and about one-third of this sum was contributed by Germany, for whom the canal is of the greatest strategic importance in case of war, for her fighting ships need not then traverse foreign waters. The construction was therefore pushed forward with unusual energy, as many as 8,600 men having been engaged on the works at one time. An important naval station already exists at Kiel, the Baltic end of the canal, where there is a splendid harbour. The engineer and designer of this water-way is Herr Otto Baensch, who has devised much ingenious machinery in connection with the immense tidal locks at the extremities of the canal, and the swing bridges by which several lines of railway are carried across it. In the construction of this canal there were no vast engineering difficulties to be overcome, and hence striking feats of mountain excavation or valley bridging are not to be met with in its course, though in places there are some deep cuttings. The methods of excavating and of steam dredging that were made use of have already been illustrated in relation to the other works described in this article. The country through which the canal passes does not present any unusually picturesque features.

THE PANAMA AND NICARAGUA CANAL PROJECTS.

The several undertakings described in our chapter on Ship Canals are now all completed and in active operation, and but for financial mis-management and dishonest speculations, the same might probably have been said of another great project, the name of which was on everyone’s lips a short time ago, but in which public interest has lately waned; perhaps from a mistaken impression that the construction itself is involved in a common ruin with the fortunes of so many of its promoters, or that the scheme was frustrated by some unforeseen and insurmountable engineering difficulties. These assumptions have so little justification that it is quite probable that Lesseps’ last great project may yet be completed under more favourable auspices, and the Panama Canal unite the Atlantic and Pacific Oceans. The Panama Canal Company still exists, and possesses not only a very large part of the work almost quite finished, but all the extensive plant in perfect condition for resuming operations. The original scheme provided for a tidal water-way between the two oceans, without the intervention of a single lock. The canal was to be nearly 47 miles in length, 100 feet wide at the surface of the water, 72 feet wide at the bottom, and 29 feet deep. The entrances are at Colon on the Atlantic side, and at Panama on the Pacific. The latter is the eastern extremity, and the western one is on the Atlantic side, owing to the configuration of the isthmus which curves round the Panama Gulf that opens to the south. A railway crosses the isthmus between the points already named, and the route of the canal is laid down almost parallel with this railway, from which it is nowhere far distant. For the first 20 miles from the Atlantic side the land is only at a very moderate elevation above the sea-level, say 25 or 30 feet, but the next 11 miles is more hilly, the elevations reaching at some points 150 to 170 feet, but these are only for short distances. A few miles farther on, they rise still higher, until at Culebra the highest point is met with, about 323 feet above the sea-level, and a cut of this depth, 1,000 feet long, would be required. Through this highest part it has been proposed to drive a tunnel, but the total extent of the deep cutting at this part of the canal would be nearly 2 miles in length. This would no doubt be a work of the most formidable magnitude, for it has been calculated that no less than 24,000,000 cubic yards of material, consisting for the most part of solid rock, would have to be removed. It is not supposed, however, to offer any great difficulty in an engineering point of view. Doubtless it would be costly, and would take some time to accomplish. Another heavy piece of work would consist in constructions for controlling a mountain torrent called the Rio Chagres, through the valley of which the canal passes. This stream is very variable in the quantity of water it discharges, rising in the rainy season 45 feet above its ordinary level, and sending down forty times as much water as it does in the dry season.

Mr. Saabye, an American engineer, who examined unofficially the works of the Panama Canal in 1894, considers that about one half of the total excavation has already been done, and one half of the total length of the canal almost finished, and remaining in comparatively good condition. At both ends, including 15 miles on the Atlantic side, there is water 18 to 24 feet deep. “Besides the work already done, the Canal Company has on hand, distributed at both terminals, and at convenient points along the canal route, an immense stock of machinery, tools, dredges, barges, steamers, tug-boats, and materials for continued construction. At Panama, La Boca, and Colon, as well as along the canal, are numerous buildings—large and small—for offices, workshops, storehouses, and warehouses, and for lodging and boarding the men who were employed on the work. The finished work, as well as all the machinery, tools, materials, buildings, etc., are well taken care of and looked after. The Canal Company employs one hundred uniformed policemen, besides numerous watchmen, machinists, and others, whose sole duty consists in watching the canal and looking after needed repairs of plant and care of materials. In fact, the work and the whole plant is in such a condition, so far as I could ascertain, that renewed construction could be taken up and carried to a finish at any time it is desired to do so, after the Company’s finances will permit.”

An enormous amount of money has already been expended on the Panama Canal, and much of it lavishly and unnecessarily. A reorganised company may probably be able to form such estimates of the probable cost of completing the work under careful and efficient management, that financial confidence in it maybe restored. The canal not only already possesses the requisite plant, but the route has the special advantages of assistance in transport from the railway everywhere at but a short distance from it, and fine commodious harbours for its ocean mouths. If it were finished as originally designed, vessels could pass through it with one tide, say in about six hours. It is understood that before the Panama enterprise is again proceeded with, the Company think that a sum of about £25,000 should be expended in a complete survey and re-study of all the conditions, and the results submitted to the most eminent engineers.

A rival scheme for carrying a ship canal across the isthmus that divides the Atlantic and Pacific Oceans is that known as the Nicaragua Canal, as the proposed route is to cross Lake Nicaragua, an extensive sheet of water situated some 400 or 500 miles north-west of the Panama Canal. The lake is 110 miles long and 45 miles broad, and is on its western side separated from the Pacific by a strip of land only 12 miles wide, having at one point an elevation not exceeding 154 feet, which is probably the lowest on the isthmus. The lake drains into the Caribbean Sea on the east, by the San Juan river, a fine wide stream, 120 miles in length, which is navigable for river boats from the Caribbean Sea up to the lake, except near its upper part, where some rapids at certain times prevent the passage of the boats. This canal project first took definite form in 1850, when a survey was made and routes reported on. The scheme attracted some attention in the United States, and in 1872, and again in 1885, further surveys and estimates were made at the instance of the States Government. The earlier schemes provided for the rise and fall between sea and lake-–108 feet, a considerable number of locks—eleven on each side, making the total length from sea to sea 181 miles. The report of the latter advocated the canalization of the San Juan by a very bold measure, namely, the construction of an immense dam, by which the waters were to be retained in the valley for many miles at the level of the lake. A company was formed to promote the project, and again in 1890 there were more surveys and estimates made. This company actually expended a considerable sum of money in attempting to improve the harbour at Greytown, which would have formed the eastern terminus, but had become silted up. But it was found afterwards that it would be better to recommend the formation of an artificial harbour at another point, by constructing two long piers running out into the sea, although this change would involve the abandonment of a few hundred yards of canal already excavated by the company near Greytown. The company has also laid down about 12 miles of railway along the proposed route, with wooden and iron sheds as workshops, offices, etc., and, moreover, had dredges and other appliances at work. At this stage it was proposed that the United States Government should guarantee the bonds of the Nicaragua Canal Company to the extent of more than twenty million pounds sterling. By an Act of Congress passed in March, 1895, a commission of engineers was appointed for the purpose of ascertaining the feasibility, permanence, and cost of construction and completion of the Nicaragua Canal by the route contemplated. The report of this commission is an elaborate and exhaustive review of the whole scheme based upon a personal examination of the route, and on the plans, surveys, and estimates made for the company, whose records, however, are stated in the report to be deficient in the supply of many important data. The Canal Company’s project provided for the improvement of Greytown harbour, as already stated, and from that place the canal was to proceed westward at the sea-level to the range of high ground on the eastern side of the isthmus, which elevation was to be ascended by three locks of unusual depth, and a deep cut more than 3 miles in length, through rock to a maximum depth of 324 feet. After passing this enormous cut, the route provides for a series of deep basins, in which the water is confined by numerous dams or embankments, the canal excavations being confined to short sections through higher ground separating these basins. The total length of these embankments will be about 6 miles, and their heights will vary from a few feet to more than seventy. About 31 miles from Greytown the canal reaches the San Juan river, which, however, by means of an enormous dam across the valley at a place called Ochoa, 69 miles below the point at which it receives the waters of Lake Nicaragua, is there practically converted into an arm of the lake. This dam, which would raise the water of the river 60 feet above its present level, and would, of course, flood the valley back to the lake, is the most notable feature of the project. Its maximum height would be about 105 feet, and the weirs on its crest, to discharge the surplus water, would require a total length of nearly a quarter of a mile. Twenty-three smaller embankments would also be needed for retaining the waters; the river would have to be deepened in the upper part, and a channel dredged out in the soft mud of the lake for 14 miles beyond the river. The big Ochoa dam is said to have no precedent in engineering construction, on account of its great height and the enormous volume of the waters it is intended to retain. No doubt its construction and safe maintenance are within the range of engineering skill, when a thoroughly exhaustive survey of the site has been made, and the necessary funds are forthcoming. From the western shore of the lake its level would also be extended by another great dam crossing the valleys of the Tola and the Rio Grande, with a length of 2,000 feet and a height of 90 feet. The canal would then be carried to the sea-level by a series of locks. The length of the canal from sea to sea would be 170 miles, but of this only 40 miles of channel would require to be excavated. The total cost of the work, as estimated by the Nicaragua Canal Company, would be about fifteen million pounds sterling, but the State Commission of Engineers thinks about double that amount would be a safer calculation, and taking into account the imperfection of the data, even this might be exceeded in certain contingencies. The Government of the United States has been urged to expend a few thousand pounds on another engineering commission, to make complete surveys, and consider all the practical problems involved, including the final selection of a route.

Fig. 138.Britannia Bridge, Menai Straits.

                                                                                                                                                                                                                                                                                                           

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