one of the most important branches of the mechanical industry of the United Kingdom. The progress made in recent years presents two remarkable features. Not only has the number and aggregate tonnage of the vessels constructed been rapidly increasing; but, what is even more important, there has been a very large increase in the number of iron steamers, and a large decrease in the number of sailing-vessels, constructed in later as compared with earlier years. In 1851 the total number of

had decreased from 594 in 1851 to 485 in 1871- a decrease of twenty per cent. in number. Their tonnage had decreased from 126,914 to 60,260 tons-a decrease of more than fifty per cent. These numbers, however, do not indicate the whole of the additions which have been made in the carrying power of the British merchant navy. For a steamer engaged in the home and coasting trade can do four or five times as much work as a sailingvessel, and for long voyages their value is three timc3

Of

vessels built and registered in the United Kingdom was only 672, and their aggregate tonnage 149,637 tons. this number, 594 were sailing-vessels, with a total tonnage of 126,914 tons. Only seventy-eight were steamers, and their tonnage was 22,723 tons. In 1871 the total number of vessels built and registered in the United Kingdom had increased to 1,022, with an aggregate tonnage of 391,058 tons. The number of steam-vessels was 537, or nearly seven times as many as were built twenty years before. Their aggregate tonnage was 330,798 tons, or more than fourteen times the tonnage of the steamers built in 1851. The sailing-vessels, on the other hand,

that of sailing-vessels. The carrying power of the who's of the vessels built in 1871, when this difference between the value of steam and sailing vessels is allowed for, will, in fact, be found to amount to nearly eight times as much as that of the whole number built twenty years before. Another change observable in the class of steamvessels constructed at the later period is their large increase in size or tonnage. The average tonnage of steamers built in 1851 was 291 tons; in 1871 it was 616 tons, or more than double the average tonnage of the steamers of the earlier date.

The shipping built for and sold to foreign nations and

Besides these vessels, there were, in the earlier year, 297 other vessels transferred from the British register as sold to foreign or colonial buyers; their tonnage was 102,916 tons. In 1871 there were 284 vessels so transferred and sold, their tonnage being 104,724 tons.

It may here be pointed out that the value of the shipping sold to foreign nations and the colonies has never yet been included in the official returns of the exports of the United Kingdom, nor do the imports include the shipping bought from foreigners or the colonists. No reason is assigned for these omissions; nor can the returns of imports and exports be considered complete so long as these

important items are excluded.

steam-vessels with 1,319,612 tons. The total number of vessels was therefore 25,892, or 151 fewer than in 1851; while the tonnage was 5,694,123, or 2,031,779 tons more than in 1851. The increase in the number of the steam. vessels in the twenty years was 2,155, and in their tonnage it was no less than 1,132,925 tons. While the number of steam-vessels had therefore increased nearly threefold, their tonnage had increased sevenfold. While the total tonnage of the mercantile navy has therefore only increased nominally by about fifty-five per cent., the real shipping power of the United Kingdom, when we take

into account the far higher value of steam-ships as compared with sailing-vessels, has been increased in the twenty years by more than 125 per cent.—that is, has been considerably more than doubled. The number of registered vessels employed in the home and foreign trade, exclusive of the river steamers, was 18,184, with a tonnage of 3,360,935, in 1851; and 22,207, with a tonnage of 5,633,561, in 1871. The steamers so employed numbered 520, with 144,741 tons, at the earlier date; and 2,557, with 1,290,003, at the more recent date-that is, five times as many vessels, with eight times the tonnage.

The number of merchant seamen employed in the coasting and foreign trade stood at 141,937, of whom 10,660 belonged to steamers, in 1851; while in 1871 they numbered 199,738, of whom 58,703 were employed on steam-vessels-that is, more than five times as many as in 1851.

The increase which has taken place in the shipping trade of the United Kingdom is shown by the total tonnage of the vessels which entered and cleared at the various ports of the country. In 1851 this amounted to 15,980,198 tons; in 1871 it was 41,547,878 tons, or nearly three times the total at the earlier date. Of the total in 1851, 9,820,876 tons belonged to British vessels, and 6,159,322 tons to foreign or colonial vessels. In 1871 the proportion belonging to British vessels had increased to 28,034,748 tons; that belonging to foreign and colonial vessels was 13,513,130 tons. The British tonnage had therefore increased to nearly threefold the amount in the interval, while that of the rest of the world engaged in the same trade had little more than doubled. The tonnage of foreign and colonial steamers entered and cleared at British ports was only 331,694 tons in 1851, and 2,480,490 tons in 1871. That of British vessels, which amounted to 1,895,076 tons in 1851, had increased to 15,361,202 in 1871. The tonnage entered and cleared of British steam-vessels at both periods therefore was, roughly speaking, about six times as much as that of the foreign and colonial steamers trading at the ports of the United Kingdom.

The merit of establishing the value of iron in the construction of ships, as well as in bridges and in other novel applications, belongs mainly to Sir William Fairbairn. "The iron ship,” he tells us, "in lightness, durability, and capacity of cargo, is infinitely superior to a vessel built of wood; and, if properly constructed and carefully looked after, will last more than double the time of vessels composed of the best teak and English oak. It is not, however, durability alone that constitutes the value of the iron ship; its superior strength insures greatly increased security to the owners, and, what is of much greater importance, to the crew and passengers. Again, as regards cargo, there is less risk from damage, as the iron ship is virtually without joints, perfectly water-tight, and free from bilge-water and that creaking motion observable in the joints of a wooden vessel plunging in a heavy sea. No such motion occurs with an iron-built vessel, as the sheathing plates, when carefully riveted, embody a principle of homogeneity sufficiently powerful to withstand the repeated shocks of the elements, to which a similar

structure of wood would succumb. Another advantage of iron vessels is their superior lightness and increased area of space. In the iron ship this enlargement of the interior contents is so great as to enable the vessel to carry from one-eighth to one-tenth more cargo on the same draught of water than a vessel built of wood."*

"Even so recently as 1845," the same writer remarks, "iron ships were scarcely known; and it required another decade to convince the public that iron was a lighter, safer, and more durable material for shipbuilding than wood." And he has since added, prophetically, "I have no doubt that the iron ship of British origin will yet ride triumphant on every sea, as the harbinger of peace, the supporter of commerce, and the great and only security of national defence."

The earliest mention of iron in the construction of vessels is in connection with the navigation of canals. In the year 1812 or 1813 certain iron boats are spoken of as plying on canals in the county of Stafford. Ten years later the first iron steamer that went to sea was built. This was the Aaron Manby, which was navigated by Sir Charles Napier from London to Havre, and thence up the Seine to Paris. In 1824 a small iron steamer was constructed by Mr. Grantham, and sent to Ireland, where it was employed on the Shannon. About the same time Sir William Fairbairn built four iron vessels, two of which, the Lord Dundas and the Manchester, were in use for many years in Scottish waters.

Having convinced himself of the applicability of iron to the building of ships, Sir William Fairbairn came to London, and in 1835 founded the first great iron shipbuilding yard at Millwall, on the Thames. Within fourteen years from that date he had built more than a hundred and twenty iron ships, some of them of more than two thousand tons burden. In the meantime the new idea was taking root in other parts of the kingdom; and the foundations of the great establishments on the Clyde, on the Mersey, and on the Tyne, were laid by the Napiers, Lairds, and others. The steam riveting-machine devised by Sir W. Fairbairn materially contributed to the progress of this new branch of industry.

As

The first very large iron vessel was the Great Britain, built in 1845 by Mr. Brunel. She was of double the tonnage of any vessel previously afloat. She made her first voyage in 1845, and reached New York in fourteen days twenty-one hours, where her unusual proportions and novel character created much astonishment. with so many of Brunel's great creations, this vessel was destined to meet with misfortune. She left Liverpool on the 22nd of September, 1846, and within ten hours struck on the Irish coast. The attempts to float her again involved a series of operations, attended with vast expense, and it was not until August, 1847, that she was at length got again into the water. But these misfortunes were not without their use. Indeed, a more satisfactory proof of the value of iron in the construction of ships could hardly be desired than that which was supplied by this accident. For a whole winter-indeed, for nearly a whole

* Sir William Fairbairn: "On Iron Ships and Shipbuilding."

A.D. 1871.]

year-the Great Britain was exposed to the action of heavy seas beating her upon the sands and rocks of Dundrum Bay, and she went through this ordeal without suffering any serious damage in her hull or in any other part. A vessel of wood could not have survived under similar circumstances, but would have quickly gone to pieces. The strength of iron and its value in shipbuilding was indeed triumphantly vindicated by this practical test, which only confirmed the scientific experiments made by Professor Hodgkinson, who showed that the comparative resistance of wrought iron to a direct crushing force is more than seven times as great as that of the best British oak.

Ten years after the construction of the Great Britain Mr. Brunel commenced the Great Eastern, by far the largest vessel ever built. Mr. Scott Russell was the naval architect, and the wave principle and lines he advocated were adopted in the construction of the vessel. It was built in the yard at Millwall, where Sir W. Fairbairn first applied iron on a large scale in shipbuilding. The dimensions of the vessel are extraordinary. Her length is 680 feet, her breadth 83 feet, her depth 58 feet. Mere numbers, however, fail to give an adequate idea of the vast proportions of the vessel. It has been well said that the Great Eastern is as big as a cathedral. The largest cathedral in the world, that of St. Peter at Rome, is only 613 feet long in external measurement, so that the Great Eastern is longer than St. Peter's by nearly seventy feet. The vessel could, in fact, be fitted up so as to carry comfortably the whole population of a town of 10,000 inhabitants. Her tonnage is 23,000, and she carries when loaded 18,000 tons of coals and cargo. Her paddle-wheel engines are of 1,000 nominal horse-power, and her screw-engines 1,600. The paddlewheels are fifty-eight feet in diameter, and therefore advance sixty yards in a single revolution. Her screw is twenty-four feet in diameter, or four and a half times the average height of a man. This magnificent vessel, however, as a commercial speculation, proved a failure. After a vast sum of money had been spent on building her, it was found that the preparations made for launching her were quite inadequate, and it required months of labour and an additional expense of £70,000 before that object was attained. This, however, was only the beginning of her financial troubles. She was intended to carry the India and China mails on the long route, round the Cape, but the idea had to be abandoned. In 1859 a destructive explosion took place on board while she was in the Channel off Hastings. After this she encountered a hurricane in the Atlantic, which damaged her paddles and disabled her rudder. She afterwards ran upon a rock at New York, and broke her bottom plates for a length of eighty feet. Another proof of the value of iron in shipbuilding was, however, afforded by these accidents; for though they would have destroyed any wooden ship, the Great Eastern received no material injury either to her hull or machinery. The vast gap which was made in her by the accident near New York she was capable of repairing without going into dock, and while still afloat, since, as is usual in iron ships, she had an inner and an

597

outer skin. She had, in fact, a system of water-tight compartments; and further, what is less general in vessels of iron, these compartments were longitudinally divided by fore and aft bulkheads. Thus the vessel might be pierced and rent open in several compartments at once, and yet she would not sink. A large portion of her hull is double, and the outer skin, which is two feet from the inner, is connected with the latter on the cellular or tubular principle. Thus, though an iron ship, the Great Eastern, from the mode of her construction, is not only the safest, but also the strongest vessel in the whole mercantile navy of the world.

Among the most stupendous products of the iron industry of Great Britain, the most recent vessels of the war navy, with their armour and equipment of guns and machinery, hold perhaps the highest place. The first use of vessels defended by iron armour was during the Crimean War, when some iron-plated gun-vessels were built by both the French and the English Governments. The achievements of the Merrimac, the Monitor, and other armoured vessels during the American Civil War at a later period, which were watched with the greatest interest by European Powers, were generally regarded as settling the question as to the comparative merits of armoured and unarmoured ships. The French Government, with its plated frigate La Gloire, opened a new era in naval armaments. The English Government quickly followed with the Warrior, a much stronger ship. The iron plates of the Warrior were four and a half inches thick, and it was supposed she was almost invulnerable. To decide the question, a large target was constructed, representing a section of the side of the vessel amidships. On the first trial it was only slightly cracked when fired at with a 68-pounder gun; but subsequently, when a 150-pounder cannon, fired with a charge of 50 lbs. of powder, was brought to play upon it, the target was penetrated. Henceforward a battle commenced, in which artillerists were ranged on one side, and naval architects on the other. Sir William Armstrong, Sir Joseph Whitworth, Captain Fraser, and Major Palliser were among the leading representatives of the first; Mr. E. J. Reed and Captain Cowper Coles of the second. The Warrior target, whose armour plate was four and a half inches thick, having been vanquished by the guns, the iron plates were increased in thickness. In the Minotaur the armour was five and a half inches thick, but this, too, soon succumbed completely to a steel shot from a 150-pounder gun. In the Bellerophon the armour was increased to six inches, while behind the wood of the vessel there was an iron inner skin of one and a half inches thick. The Bellerophon target successfully withstood a 150-pounder gun fired at a distance of only 200 yards, the effect of the shot being only to crack and bulge it to some extent. But a larger gun was now brought to bear on it by the artillerists. This threw a shot of 300 lbs., and before this tremendous missile the target gave way. The next step was to add again to the thickness of the armour, and in the Hercules the outer plates were eight and nine inches thick. A cylindrical 300 lb. shot was fired, with 45 lbs. of powder, at the nine

inch Hercules target, from which it jumped back sixteen yards, making only a rather deep indentation in the plate. But now the artillerists had doubled the size of their gun, and had enabled it to throw a shot of nearly 600 lbs. A missile weighing 573 lbs., with a charge of 100 lbs. of powder, was next hurled at the target. The shot, which was of cylindrical form, and seventeen inches long, buried itself in the target so far that only three or four inches of it protruded from the plate. The target was, however, so far victorious over this prodigious weapon. It was not pierced, though the inner skin was bulged, one of the ribs broken, and some rivet heads forced off. Next, however, was tried one of Major Palliser's chilled iron shot, weighing 577 lbs. It was fired with 100 lbs. of powder, and, striking the target just above the previous shot, completely penetrated it, breaking one rib, bulging others, and tearing away the inner skin, the shot itself breaking up into small fragments. Armour-plating, after this, advanced again in dimensions till, at the most recent dates, it had attained a thickness of upwards of a foot. And the battle between naval architects and artillerists still rages, the question between them not yet being decided; the probability, however, being in favour of the

former.

In recent years the application of the screw in place of paddle-wheels for the propulsion of steam-vessels has been rapidly gaining ground. Though paddle-wheels give a smoother motion to the vessel, they are more liable, particularly in ocean voyages, to injury than the screw. The screw-propeller-which is usually fixed in the "deadwood," immediately in front of the sternpost of the vessel, and is turned by a shaft, runuing parallel to the keel, from the engine-room-is somewhat similar in construction to the common screw, the narrow thread of the latter being expanded into a broad thin plate, while the cylinder is reduced to a mere spindle. Many attempts were made to apply the principle of the screw to the propulsion of vessels in water before practical success was attained. In 1840 the performances of the Archimedes screw-steamer convinced the British Government of the value of the invention; and its obvious advantages over the paddle for war purposes have caused its adoption in all the most important vessels of the royal navy; while it possesses for ordinary purposes such advantages over the paddle, particularly for vessels intended to make long voyages, that it has been widely adopted in the merchant navy. The screw of the Great Eastern steam-ship, as already observed, is no less than twenty-four feet in diameter. Many attempts were made in the early days of steam navigation to introduce the principle of the screw-propeller, and there are numerous claimants to the honour of the invention. In a debate in the House of Commons in 1855, on the grant of £20,000 for rewarding the inventor of the screw-propeller, it was stated that no fewer than forty-four persons had sent in claims for the reward. The number, however, was, on examination, reduced to five, amongst whom the money was divided by arrangement. Mr. Pettit Smith, who shared in the reward, patented his invention in the year 1836. It was with Mr. Smith's screw that the Archimedes was fitted,

whose performances induced the Government to adopt this mode of propulsion in the royal navy. Many of the most competent judges belonging to the engineering profession accorded to Mr. Smith the principal share, if not the whole, of the merit of having brought the screw intɔ general use; as is evidenced by the fact that at a public dinner given in his honour in London, and presided over by Robert Stephenson, they presented Mr. Smith with a splendid and valuable testimonial. This was in the year 1858, at which time 174 vessels of the royal navy, including 52 line-of-battle ships, 23 frigates, 17 corvettes, 55 sloops, 8 floating batteries, and 19 troop and store ships, had already been fitted with screw-propellers.

The substitution of steam power, in place of sails and wind, for the propulsion of ships is now almost universal in the case of the war navies of the world, but in the mercantile navies it is still only partial. It has, however, been progressing rapidly in all the mercantile navies of the world, more especially of late years. Thus, in the three years between 1870 and 1873, sailing-vessels throughout the world had decreased nearly five and a half per cent. in number, and more than eleven and a half per cent. in tonnage. Steamers, on the other hand, had increased no less than twenty-four and a half per cent. in number, and nearly fifty-five per cent. in tonnage. This rapid revolution in the character of seafaring vessels is mainly due to the great intrinsic advantages possessed by steamvessels over sailing-vessels, as shown by the fact already mentioned, that in short voyages a steamer can do four or five times as much work as a sailing-vessel.

The increase of steam-vessels, and the decrease of sailing-ships, have, as predicted by Mr. Samuda, been accelerated to some extent of late by the completion of the great undertaking by which the waters of the Mediterranean and Red Seas have been united. The Suez Canal was projected and executed, in spite of much opposition and many difficulties, by a French engineer, M. Ferdinand de Lesseps. Before the opening of the canal, which took place in the year 1869, the voyage from Liverpool to Bombay was longer by upwards of 5,500 miles, and to Hong Kong by 3,500 miles, than it was by the new route. When vessels could reach the Eastern seas only by a voyage round the Cape, sailing-ships were more economical than steamers, on account of the excessive quantity of coal required for the voyage by the latter. But the Suez Canal shortened the voyage to the nearest ports of India by nearly one-half, and that to China by one-fourth, and thereby removed the great obstacle to their employment in the Eastern trade. Of the vessels passing through the canal, those sailing under British colours considerably outnumber those of all other nations put together.

At the point selected for the canal, the Isthmus of Suez is not more than seventy-two miles wide, measured as the crow flies. The canal itself, however, is 100 miles in length. There are numerous lagoons and lakes in the neighbourhood, separated by a distance of a few miles from each other, and advantage was taken of several of these to abridge the work of excavation. The canal passes through the lagoons of Menzaleh an Ballah.