CHAPTER XIII.
Eastern Steam Navigation Company—Detailed proposals of the directors—Capital subscribed to build the Great Eastern—Relative size and speed of sailing-ships—Mr. Brunel proposes to build a ship five or six times as big as any existing vessel, and is supported in his views by Mr. Scott Russell—Plan of construction, size, &c.—Mr. Atherton considers the views of the directors are not supported by their data—The Great Eastern commenced May 1, 1854—Details of her dimensions and mode of construction—Practically, one ship within another—Compartments and bulkheads—Floor—Construction of the iron plates for hull—The deck and its strength—Enormous steam-power from combination of paddle and screw—Paddle-wheel, auxiliary, and screw-engines—Donkey-engines—Proposed accommodation for passengers, &c.—View of deck, &c.—Saloon—Intended to carry twenty large boats and two steamers—Compasses—Size of sails—Magnetic apparatus of Mr. J. Gray—Apparatus for steering—Rudder and anchors, and note—The ship itself a marvel though, commercially, a failure—Preparations for, and details of, the launching of the Great Eastern.
Eastern Steam Navigation Company.
In tracing the progress of steam navigation to the East the various tenders for the conveyance of the East India and Australian mails have been incidentally noticed. Among those which were lodged, in reply to an advertisement from the Admiralty issued on the recommendation of Lord Jocelyn’s Committee of 1851, there was one from a new undertaking—the Eastern Steam Navigation Company—offering to convey the mails from Plymouth to Sydney and to the East Indies, &c., monthly, viâ Alexandria, in vessels of from 1300 to 2100 tons, with engines of from 400 to 600 horse-power.[412] This company had been incorporated by royal charter with a nominal capital of 1,200,000l. in 20l. shares, having power to increase it to 2,000,000l. The projectors of the proposed undertaking were, in the highest degree, respectable, comprising some men of great wealth, and others of well-known scientific attainments. They were, in every way, competent to carry out the service they had tendered to perform. The general impression, at the time, seemed to be that they intended to act in concert with the Austrian Lloyd’s Steam Navigation Company, a well-known undertaking trading from Trieste to different ports in the Mediterranean and represented in London by the late Mr. Joseph Edlmann, a merchant of the highest standing, whose name appeared as one of the directors of the new undertaking. But, as the ships the company intended for the service to India and Australia were not mentioned, and more especially as the directors did not state in their tender the sum they required for the performance of the latter service, their offer was not accepted, though it may have been considered.
Detailed proposals of the directors.
After the directors had communicated to the shareholders the result of their tender, some of them, on the suggestion of Mr. I. K. Brunel, recommended the construction of a steam-ship of extraordinary dimensions to trade with India. On looking at the export and import trade of Great Britain they observed that the main line of commerce passed round the Cape of Good Hope towards India, China, and Australia, following nearly the same track as far as Ceylon. On the fact of this great pathway of commerce they grounded, and not without plausible reasons, their scheme for the profitable employment of various vessels of gigantic size between England and Ceylon, from which place smaller vessels were to diverge to the other parts of India, as well as to China, Japan, and Australia; the intention, however, being to despatch their first great vessel, when ready, direct either to Calcutta, Sydney, or Melbourne.
Having made the calculations (to their own satisfaction) that such ships would maintain a speed of fifteen knots per hour, there was in their judgment no doubt that they would “attract so large a portion of the traffic as to afford full cargoes at remunerative rates both outward and homeward.” The voyage from England would thus be accomplished in thirty days to Trincomalee, which had been selected for their central station, as it offered every facility for such a purpose. Thence they estimated that the voyage in ordinary steam-vessels could be accomplished to Madras in two days, Calcutta in four, Hong Kong in ten, and Sydney or Melbourne in fourteen respectively; the auxiliary steamers on these lines transferring the outward cargo from the leviathans, and bringing to them “the valuable products of all these countries as a back freight to England.”
“Should the great ships,” they said, “fulfil only the most moderate of the anticipations, in regard to speed, and be able to land goods in Calcutta within thirty-five days of their shipment in London, in Hong Kong within forty, or in Melbourne within forty-four, it is certain that they will take up at higher freights a large amount of goods now conveyed in ordinary vessels. Of the whole Eastern tonnage, all that portion which will bear a minimum freightage of 5l. per ton, may be fairly calculated on as cargo available for their ships. Of such are the silks and silk piece-goods of India and China averaging from 2000l. to 3000l. per ton in value; indigo from 500l. to 1000l. per ton; tea, coffee, spices, lacdye, shellac, &c., of the value of between 100l. to 300l. per ton. Among the export goods intrinsically valuable enough to pay the higher rates of freightage may be reckoned the principal manufactures of Birmingham, Manchester, Sheffield, and Leeds: woollens, silks, satins, velvets, millinery, haberdashery, oilmen’s stores, and hardware, besides the costly productions of France and Germany.”
Going into various calculations in detail, they arrived at the conclusion that out of the exports to India there would be 180,000 tons of goods able to afford the minimum freight, without considering the goods at that time transported by the overland route in the ships of the Peninsular and Oriental Steam Navigation Company, the greater portion of which the directors of the great ship company felt certain they would secure, while they were, further, convinced that their ships would “attract a considerable portion of the exports to Australia were a line of branch steamers to be laid on from Trincomalee to the Australian ports.”
The import trade, in the opinion of the directors, was even more valuable than the export, and could “well afford a higher freightage in return for speedy transport.” The Aberdeen clippers they said “obtain from 8l. to 12l. per ton for the carriage of fine teas from China, in which trade they will be utterly unable to compete with their great ships should they reduce the voyage from 80 to 40 days.” Estimating at least 50,000 tons of tea from China should the freight not exceed 6l. or 7l. per ton, and, without considering the large and rapidly increasing amount of that article imported from Assam and the Himalayas, the tea from China in itself would be, in the opinion of the directors, an enormous source of profit. Then, should they reduce the voyage from Australia to 45 or 50 days, they might calculate with certainty on obtaining “the conveyance of all the gold from that country.” In a word, they were of opinion that, after making the most ample allowance for working expenses, wear and tear, depreciation and insurance, “a surplus would remain equal to 40 per cent. per annum on the capital invested.”[413]
Capital subscribed to build the Great Eastern.
Nor were the vast and increasing number of passengers overlooked in their calculations as affording a larger source of profit than even gold or merchandise, while, in their opinion, “for the transport of troops the capabilities of their ships would be such as always to command a preference from Government over vessels of smaller burden.” Such were the views and calculations of the directors of the Eastern Steam Navigation Company.
Nevertheless, in spite of these glowing prospects, many of the shrewd and more cautious shareholders in the original undertaking, including nearly all the persons interested in the Austrian Lloyd’s Company, preferred receiving back the money they had deposited, on account of their shares, and declined to support the new company. Others, however, and among them many men of great capital and of high position in the world of science, consented, and, after considerable difficulty, sufficient capital was raised to construct the Leviathan, the largest ship ever known either in ancient or modern times, and the first, as well as the last, of the ships of this size they had contemplated building.
Relative size and speed of sailing-ships.
About this time the important question of increased speed in combination with increased dimensions was receiving the special attention of scientific men, and was discussed with great animation at the meetings of various associations. Mr. Charles Atherton, the chief engineer of the Royal Dockyard at Woolwich,[414] had taken the lead in forming public opinion on the novel problem of steam-ship capability. As regards sailing-vessels it had been observed that the average length of their voyages to Australia bore the following relation to their tonnage:
| Tons. | |
| 750 to 1000 | took 140 days. |
| 1000 to 1500 | took 112 days. |
| 1500 to 2000 | took 95 days. |
| 3000 and upwards | took 70 days. |
Mr. Brunel proposes to build a ship five or six times as big as any existing vessel, and is supported in his views by Mr. Scott Russell.
The inference drawn from these and similar observations, more or less founded on correct data, was that, to obtain high velocities in sea-going vessels, it was merely necessary to make them large; it being argued that a mass of two or three thousand tons, once set in motion at a given speed, would overcome the resistance both of atmosphere and water with greater ease than a mass of half its weight. Mr. I. K. Brunel carried these opinions to an extreme length, and argued that there need be no limit to the size of a vessel, except what tenacity of material must impose. He further argued, from scientific theory and actual experience, that as the “tubular principle” provided the greatest amount of strength of construction with any given material, it, therefore, was possible to construct a ship of six times the capacity of the largest vessel then afloat, and one, too, that would steam at a speed hitherto unattainable by smaller vessels. Mr. Brunel, having originated this conception, communicated it, at the outset, to Mr. Scott Russell, and suggested the construction of a steam-ship large enough to carry all the fuel she might require for the longest voyage; and Mr. Scott Russell shared with Mr. Brunel in the merit of contriving the best method of carrying out these views. The idea of using two sets of engines and two propellers (screw and paddle) is solely due to Mr. Brunel, as was, also, the adoption of a cellular construction, like that at the top and bottom of the Britannia Bridge, in building the Great Eastern, the name this huge ship was now to bear.[415] These main characteristics distinguished the Great Eastern from all other vessels then afloat. Her model and general structure were in other respects identical with those of the ships built by Mr. Scott Russell, on the principle of the “wave line,” which he had systematically carried out during the previous twenty years.[416]
Plan of construction.
Having obtained the requisite capital, the directors now concluded provisional arrangements for the construction of the screw-engines with Messrs. James Watt and Co., of the Soho Works, near Birmingham, and for the paddle-engines and hull with Messrs. Scott Russell and Co., of London. But, considering the novelty and magnitude of the undertaking, it may be interesting and instructive to review, still further, the grounds on which the projectors anticipated its success.
The ship, the directors said, “would be built in the Thames, to be completed in eighteen months; and would fulfil certain conditions, the most important of which was that she should not be obliged to stop at any place on the way to take in coal, stoppages for coal not only causing great delay by the time required for taking it on board, but compelling the vessels to deviate widely from the best route, in order to touch at the necessary coaling stations;” and, in avoiding the delay of coaling on the voyage, the ships would also escape the great cost of purchasing coals at a foreign station. “These ships,” they added, “will carry, besides their whole amount of coals for the voyage (out and home[417]), upwards of 5000 tons measurement of merchandise, and will have 500 cabins for passengers of the highest class, with ample space for troops and lower class passengers. These the company will carry at rates much smaller than those of any existing steam-ships and, moreover, with an unprecedented degree of safety, comfort, and convenience which the great size of their vessels will afford.” In thus increasing the size of their ships, the directors said, “they believed they were also obtaining the elements of a speed heretofore unknown: and if, hereafter, coals applicable to the purposes of steam navigation could be supplied from the mines of Australia, their carrying capacity both for cargo and passengers would be proportionately increased. The great length of these ships will undoubtedly, according to all present experience, enable them to pass through the water at a velocity of 15 knots[418] an hour, with a smaller power in proportion to their tonnage than ordinary vessels now require to make 10 knots.”
Mr. Atherton considers the views of the directors are not supported by their data.
These views were, however, not allowed to pass unquestioned by many scientific men, and more especially by Mr. Atherton, who rejoined that, whatever pride the projectors might reasonably feel in the production of such an extraordinary vessel as the Great Eastern, the data relied on by them did not support their anticipations. He argued that, if based upon the performance of the Rattler, the size of the vessel that would be required for the due fulfilment of the conditions of the project, as announced by the directors, would, probably, be not less than 100,000 tons displacement, and that the whole capital of the company, as proposed in their prospectus would, probably, be much more than absorbed in the construction of a single vessel of the stupendous size indispensable for the performance of 25,000 nautical miles, without recoaling, at the average speed of 15 nautical miles per hour. As an engineer, Mr. Atherton was not opposed to the construction of large ships, but he, like many other scientific and practical men, questioned the fulfilment of the mechanical conditions as respects the combination of a 15-knot speed with a 25,000-mile voyage without recoaling, on which the Eastern Steam Navigation Company had founded their project. Indeed, both practically and theoretically, he declared himself in favour of the superior capabilities of large ships as respected either speed or distance, but he forewarned the proprietors of the Great Eastern of the mercantile disappointment to which extravagant expectations, as to the combination of high speed and great length of voyage without recoaling, by the mere agency of size, would, in his opinion, inevitably lead.
The directors might, therefore, have seen that extreme caution was necessary for all mercantile steamship undertakings requiring the maintenance of so high a rate of steaming speed as they contemplated. Indeed, taking the actual results of the most successful steam-vessels of that day, it was more reasonable to doubt the realization of the hopes entertained by the projectors.[419]
The Great Eastern commenced, May 1, 1854.
Nevertheless, the sanguine expectations of the directors were in no way shaken and, under the advice and personal superintendence of Mr. I. K. Brunel, Mr. Scott Russell commenced the arduous undertaking in his yard at Millwall on the north side of the Thames.[420]
Details of her dimensions.
To prepare the ground for the reception of the enormous weight about to be placed upon it, 1500 huge piles of timber were driven through the loose surface soil into the more solid stratum below. These were girded so as to form a platform bound together by transverse and longitudinal balks of timber, between which thick beds of concrete were embedded, and, on this structure, iron rails were laid to form the launching ways, of which the following is the longitudinal section.
On this platform the first plates of the great ship, built entirely of iron, were placed, May 1st, 1854.
And mode of construction.
The hull of the Great Eastern,[421] which is of immense strength, is divided transversely into ten separate compartments of 60 feet each, and rendered perfectly water-tight, in all its parts, by bulkheads through which there is no opening, whatever, below the second deck: two longitudinal walls of iron, 36 feet apart traverse 350 feet of the length of the ship. Instead of the usual keel there is a flat plate of iron in its place, about 2 feet wide and 1 inch thick, running the entire length of the vessel from stem to stern, and so set up as virtually to form part of the base on which all the rest of the fabric is raised, whether of plates or girders. The bottom and sides which ascend immediately from this keel plate are also 1 inch tapering to three-quarters of an inch thick, the entire structure having been raised from below by adding plate to plate upwards. These plates are fastened together by more than 3,000,000 rivets, each an inch in diameter, the whole being hammered in when at almost a white heat, and welded so close as to form parts of the plates which they bind together.
TRANSVERSE SECTION.
Practically, one ship within another.
From the keel to the water-line the hull is double, having an inner and outer skin of the same thickness of iron, 2 feet 10 inches apart, between which, at intervals of 6 feet, run horizontal webs of iron plates thus materially increasing the power of resistance both of the inner and outer skin. So far, therefore, as regards the portion of the vessel immersed when laden, the Great Eastern is, practically, two ships, one within another, as may be seen by the transverse section, [page 498], which exhibits the principle of her construction.[422]
The danger of a collision at sea is, thereby, greatly lessened, for if the outer skin is pierced, the inner one, remaining intact, as it would, except under very extraordinary circumstances, the safety of the vessel would not be endangered. Looking, also, at this arrangement in a commercial point of view, should the ship require ballast, the space between the outer and inner skin can be filled with water, so that whatever may be necessary in this respect can be obtained in a very economical and expeditious mode, to the extent in weight of 2500 tons.
Compartments and bulkheads.
Besides the principal bulkheads, there is in each compartment a second intermediate bulkhead forming a coal bunker and carried up to the main deck, which can on an emergency be closed. Two continuous tunnels run through the principal bulkheads near the water-line in one of which the steam pipes pass, and, under the most improbable circumstances of damage to the ship, arrangements are made, so that facility and ample time would be afforded to close them leisurely, and to make them perfectly water-tight.
Floor.
The floor of the ship is perfectly flat, the keel being turned inwards, and riveted to the inner skin. The bow and stern have additional strength imparted to them by strong iron bulkheads specially fitted to those parts of the ship.
Construction of the iron plates for hull.
Every distinct plate employed in the construction of the hull was moulded, beforehand, to the exact shape required by the situation it was to occupy. They were each gauged according to mathematical principles, wooden moulds being first prepared from the gauges, and the iron plates and angle iron accurately fashioned to correspond with the moulds.
10,000 tons of iron plates were used in the construction of the hull, or 30,000 plates (with about 100 rivets to each), each plate weighing on an average a third of a ton.
The deck, and its strength.
The deck of the ship is double or cellular, and is formed of two half-inch plates, at the bottom, and of two half-inch plates at the top, between which are webs of iron which run the whole length of the ship. The upper deck runs flush and clear from stem to stern for a breadth of about 20 feet on either side of the skylights and hatchways, thereby affording two magnificent promenades for the passengers just within the bulwarks; these promenades are altogether more than the eighth of a mile in length, as four turns up and down either side of them exceed a mile by 640 feet. Between the two side promenades of the upper deck are several quadrangular openings edged with low bulwarks, and looking down into the recesses of the structure. These openings are 42 feet wide, and nearly 60 feet long, the longest being 100 feet, and there are deck gangways connecting the side promenades between each of them. In these spaces the skylights of the large passenger saloons are fixed.
Enormous steam-power from combination of paddle and screw.
The distinguishing feature of the Great Eastern, in addition to her vast size, is the combined application of both the paddle-wheel and the screw. The engines are considerably larger than any previously made for marine purposes. There are ten boilers and five funnels, and each boiler can be cut off from its neighbour and used or not, as desired. The boilers are placed longitudinally along the centre of the ship, and are entirely independent of each other. Every paddle boiler has ten furnaces, and each screw boiler twelve furnaces, thus giving to the whole, the prodigious number of 112 furnaces. The funnels are each about 100 feet in length measuring from the floor of the boilers to the top of the funnel.
The paddle-wheel engines, of which the following is a transverse section, are a magnificent piece of workmanship, combining vast strength with great beauty and apparent lightness of design.
When these, combined with the screw engines (to which reference will presently be made), are at work the mind is lost in wonder at the amount of mechanical power which is thus brought to play in the propulsion of one vessel, and the smoothness and harmony with which that duty is performed, in a space necessarily confined and limited, and amid the violent turmoil of the ocean. No work of art ever yet produced furnishes more exalted ideas of man’s genius and skill than the unceasing and regular motion of these gigantic engines, especially, when we consider the tremendous shocks to which they must be at times subjected, and the delicate nature of some portion of the machinery, resting as this does, not upon solid granite as is the case with land engines, but on the ever straining ribs of a ship.
Paddle-wheel,
The paddle-wheel engines have a nominal power of 1000 horses, they have four cylinders, the diameter of each being 74 inches, with a stroke 14 feet in length, giving 14 strokes per minute. Each cylinder with piston and piston-rod weighs no less than 38 tons, while each pair of cylinders with its crank, condenser, and air-pumps, forms in itself a complete and separate engine, and each of the four cylinders is so constructed that it can be, at once, disconnected when required, from the other three, so that the whole forms a combination of four engines, altogether complete in themselves, whether worked together or separately. The two cranks are connected by a friction-clutch by means of which the two pairs of engines can be connected or disconnected, by a single movement of the hand and at a moment’s warning. All the engines are provided with expansion valves, and their combined force, when working 11 strokes per minute, indicates 3000 horse-power, with steam in the boilers at 15 lbs. on the inch and the expansion valve cutting off at one-third of the stroke. But as all the parts of the engines are so formed and proportioned that they will work safely and smoothly at 8 strokes per minute, with the steam at 25 lbs. and fully open without expansion (beyond what is unavoidably effected by the slides), or at 16 strokes per minute, with the steam in the boiler at 25 lbs. and the expansion valve cutting off at one-fourth of the stroke, they can be made to give a power of 5000 horses. The paddle-shafts are each 38 feet long and weigh 30 tons, while the intermediate cranked shaft, 21½ feet in length, weighs 31 tons.
Auxiliary,
Two auxiliary high pressure condensing engines are fixed, adjacent to the paddle engines, for working the pumps and performing other necessary duties on board of the ship; these auxiliary engines are equal to 60 horse-power and can be worked to double that power if necessary.
and Screw engines.
But the screw engines are even more surprising than those of the paddles: they are also of 1000 horse-power with four oscillating cylinders each 84 inches in diameter with 4-feet length of stroke and performing 50 revolutions per minute. They can work up to 4500 horse-power with steam in the boiler at 15 lbs. and revolving at 45 strokes a minute, the expansion valve cutting off at one-third of the stroke; but, with steam at 25 lbs., without expansion, and cutting off at one-fourth of the stroke, they can propel with a power of 6000 horses, so that the combined force of paddle and screw engines gives the tremendous power of 11,000 horses! The propeller shaft, in two parts, is 160 feet in length and weighs 60 tons, while the screw-propeller itself is 24 feet in diameter with 44 feet pitch. The paddle-wheels are, however, still more stupendous, being no less than 58 feet in diameter with a boss which alone weighs 16 tons, each wheel when complete weighing 90 tons.
Abaft the bulkhead of the screw engine-room are placed two auxiliary engines of 20 horse-power each for moving the screw-propeller, when the larger engines are disconnected, at such a velocity as will prevent the speed of the vessel from being retarded when the ship is under weigh with paddles alone, or when under sails and paddles.
There are, also, two auxiliary high pressure engines, each of the nominal power of 10 horses, for working the pumps, shafting, or other parts of the machinery, and for hoisting sails, taking in or discharging cargo, lifting the anchor, and for performing many other services usually carried on by the crew.
Donkey-engines.
Each set of boilers is provided with donkey-engines, with independent boilers, and pumps of power sufficient to feed both sets of boilers, and are capable of being connected or disconnected, so that one donkey-engine may supply any set of boilers. These are each of about 10 horse-power.
Proposed accommodation for passengers, &c.
This mighty vessel was destined to afford accommodation for 4000 passengers, viz., 800 first class 2000 second class, and 1200 third class, independently of the ship’s complement of crew, amounting to about 400. The series of saloons, which were elegantly fitted and furnished, together with the sleeping apartments (as will be seen by referring to the longitudinal section in the [frontispiece] to this volume) are situated in the middle of the ship and extend over 350 feet of her length.
View of deck, &c.
As everything about this vast ship is really of historical interest, I present my readers ([see frontispiece]) with a view of her deck as seen from the bridge between the paddle-wheels, looking towards the stern, a sight which affords a more imposing appearance of her magnitude than any other view. The first skylight covers the passage to the engine-room and the captain’s cabin, which is in itself a moderate-sized house, consisting of several rooms; behind it there are other two companions or staircases leading to the after saloons. As the old-fashioned speaking trumpet would be useless in such a ship, the captain signals his orders either from his cabin or from the bridge by semaphore arms during the day and by coloured lamps at night; while electric telegrams convey his wishes, not merely to the engine-rooms, but to other places below the decks where it may be necessary that his instructions should be instantaneously communicated. With regard to the main or upper deck itself, there is ample clear space to drill a full regiment of soldiers.
GRAND SALOON OF THE “GREAT EASTERN.”
Saloon.
The lofty saloons and cabins are very imposing, differing as they do in most respects from those of ordinary passenger steam-ships, indeed, more resembling the drawing-rooms of the mansions of Belgravia of London or of the Fifth Avenue of New York. The one of which an illustration is furnished ([page 506]) bears the name of the “Grand Saloon.” The illustration, however, shows only one half of this magnificent apartment, which is 62 feet long, 36 feet in width, and 12 feet in height, with a ladies’ cabin, or rather boudoir, adjoining, 20 feet in length. Massive looking-glasses in highly ornamented gilt frames decorate its sides; the strong iron joists (beams) overhead are encased in wood, the mouldings being delicately painted and enriched with gilt beading. Around two of the funnels which pass through this gorgeous apartment are large mirrors, with alternate highly ornamented panels, and at their base are groupings of velvet couches. The columns (staunchions) which support the beams are richly decorated, while the iron work of the railings of the staircases leading to the lower cabins, or surrounding the open spaces necessary for more perfect ventilation, are, by some particular process, made to resemble oxidized silver, which is relieved by gilding. The walls (sides) are hung with rich patterns in raised gold and white, and at the angles are arabesque panels ornamented with groups of children and various emblems of the sea; other illustrations personify, in graceful forms, the arts and sciences connected with the construction and navigation of ships, while sofas covered with Utrecht velvet, buffets of richly carved walnut wood, carpets of surpassing softness, and portières of rich crimson silk to all the doorways, give an elegance to the whole, combined with a display of taste and beauty far surpassing, and an extravagance almost equalling, the gigantic toy ships of ancient monarchs.[423] Nor are the dining-rooms and family cabins much inferior in style, while the bed-rooms, in space, fittings, and comfort are all that the most fastidious voyager could expect, if not all they would desire.
Intended to carry twenty large boats and two steamers.
The Great Eastern was planned to carry twenty large boats on her deck or hanging from the davits. Some of these boats are patents on very ingenious principles. In addition, it was intended she should carry, suspended abaft her paddle-boxes, two small steamers, each 100 feet long and of between 60 and 70 tons burden. These were to be raised or lowered by small auxiliary engines and kept in all respects completely equipped for sea, but to be principally used for embarking or landing the passengers with their luggage.
Compasses.
The compasses were placed at a height of 24 feet from the deck on a staging, in order to remove them from the disturbing influences inherent in the vast masses of iron below; and it was proposed that strong shadows of the needle should be cast down a tube so that the steersman might by watching the shadow of the points at once follow the movements of the compasses above.
Size of sails.
Besides the mizen-mast, which is of wood, there are five other masts of hollow wrought iron. Two of these carry large square sails, the others fore and aft sails, the fore-mast having a jib as well as trysail, there being neither bowsprit nor jibboom. The standing rigging consists of iron wire rope, and the lower mast shrouds of this material are 8½ inches in circumference. The running gear, manufactured chiefly from Manilla hemp, is beautifully made. Instead of the ordinary dead-eyes and lanyards, an ingenious contrivance has been devised for letting go the shrouds instantaneously on an emergency. When under full sail the Great Eastern will spread 6500 square yards of canvas.
Magnetic apparatus of Mr. J. Gray.
The magnetic apparatus or floating compass invented and patented by Mr. John Gray, of Liverpool, is to the navigator, perhaps not the least interesting instrument of the great ship. The binnacle consists of an isolated battery of magnets adjusted by vertical screws, which move them in proportion to the deviation of the compass arising from the influence of the iron used in the construction or equipment of the ship. The original error having been ascertained by careful observations (a duty invariably devolving on the makers of the instrument) and the compass thus adjusted and regulated, the process of readjustment, when necessary, is so simple that, by the officer of the ship merely placing her head in two positions—north and south, east and west—the compass in the northern hemisphere can be made perfect. If any alteration takes place in the ship’s magnetism of an opposite character in the southern hemisphere, by reversing the position of the magnet and by adopting the same process, the instruments will be found as correct as in the northern. There are other applications all calculated with the utmost precision for navigating the ship, one of which is highly important, in that it corrects the dangerous influence arising from heeling. A vertical magnet is made moveable in the centre of the apparatus so as to obviate errors arising from this cause,—errors sometimes amounting, by the deflection of the needle, to 50 or even a greater number of degrees. As these disturbances produce considerable oscillating of the card when the vessel rolls, their repetition often causes a momentum that ultimately makes the card revolve with such velocity as to render it useless to the helmsman.
The patent floating compass, constructed to prevent vibration from affecting the centres of action, consists of an inner bowl floating in an outer one, the object being to render the former insulated in its water bed, the exterior being solely influenced by the action of the ship. Through a very ingenious mechanical arrangement in the interior of the inner bowl the hardest gems and the finest centres may be applied without fear of oscillation of the card. The entire combination of these essential points insures steadiness of action, perfect indication, and great durability.
There is also a vertical double disk to register the ship’s course and to show whether the man at the helm has attended strictly to his instructions with regard to the course to be steered. On each side of the binnacle there is a metal box containing soft iron for the adjustment of any small amount of deviation in the quadrants, which remains stationary with its contents throughout every change of latitude.
Apparatus for steering.
Nor must I omit notice of the mode of directing the course of the ship. On one side of the platform between the casements of the paddle-wheels (the deck most in use by the commander and officers of all steam-ships), stands an ingenious apparatus, in which there is a compass, the duplicate of the one in the binnacle, and before it an officer stands when the ship is under weigh, who is under the immediate eye of the captain. This pedestal is covered with a brass circular slide, with an aperture sufficiently large to permit of one of the points on the card being seen through it. The captain or officer in charge of the ship, by turning a handle, exposes the point at which he wishes the ship’s head to be kept, and by means of connecting rods a coincident point is disclosed on the compass in the binnacle, which is watched by the steersman, who thus knows in a moment the course he has to steer, so that, without verbal orders (which are frequently indistinctly heard and sometimes misunderstood, even when the officer is close to the helm) the ship is directed on her course with more ease than an ordinary sized vessel.
Beyond the original plan contemplated of manufacturing gas on board to be laid on to all parts of the ship, it was further intended to carry the electric light so as to secure a perpetual artificial moonlight around the vessel.
Rudder and anchors.
The rudder[424] is constructed of two plate-iron cheeks framed together on a wrought-iron rudder-post, tapering from 14 inches diameter downwards, the frame being 9 feet wide from back to belly. The space between the 2 plate-iron cheeks within the rudder-frame is filled with solid blocks of wood, bound together and bolted through the plates, combining great strength with lightness.
There are ten anchors on board which, with their stocks, weigh 55 tons, and 800 fathoms of chain cable weighing 98 tons, the capstan and warps weighing 100 tons, so that there are 253 tons weight of appliances on board devoted exclusively to the purpose of anchoring or mooring the great ship. Through the centre of her stem there are two hawse-holes each 18 inches in diameter, so that the large cable runs straight out from the stem; and, besides these, there are additional hawse-holes on each side of the cutwater.
The ship itself a marvel though, commercially, a failure.
Such is or, rather, was the Great Eastern in all the leading features of her construction and equipment, and, however fallacious many of the calculations of the directors and designers may have proved, (and none were more so than those referring to the project as a commercial undertaking),[425] they and the constructors have produced a ship which is not merely a marvel in size, but, in beauty of symmetry, strength of hull, completeness of machinery, organization, and arrangement of details, equals, if she does not surpass, any vessel that has yet been constructed for ocean navigation.
It is to be regretted that the plans for launching the monster were not (for the credit of science and the great mechanical knowledge of the age) as perfect as the ship herself. Instead of constructing a dock, wherein she could have been built with less labour than upon piles, and which would have been valuable as a graving-dock when she was floated from it, they built her in a yard, and, contrary to the established custom, built her broadside to the element into which she had ultimately to be launched.
Preparations for, and details of, the launching of the Great Eastern.
The apparatus for launching the ship consisted of two inclined planes, each about 200 feet long by 80 feet broad, and nearly 140 feet apart, falling at an inclination of one in fourteen, to low-water mark. On these ways two cradles, each 80 feet square, were destined to slide, the object being that the great ship should be moved sideways into the river on two massive platforms, underlaid with transverse bars of hard iron, and corresponding in length to the width of the launching ways upon which they rested.
The cradles were provided with two enormous chains, with crab blocks and tackle, the standing part fastened to the further bank of the river and the ends carried through two portholes, and under the ship’s bottom. Two small steam-engines in the yard worked the crabs and blocks attached to the chains whereby the ship was, if necessary, to be dragged down the launching ways, which were prepared with an anti-attrition composition to facilitate the movement of the enormous mass. Besides these powerful tackles, there were two hydraulic presses, each of one thousand tons lifting power, placed behind the cradles, to which they could be applied to set the vessel in motion should the engines prove inadequate for that purpose.
But, in order to regulate the descent of the vessel, and check her progress, should it become too rapid, two immense friction drums or capstans were constructed, and fastened firmly by means of piles into the earth, so as to resist any possible strain that might be placed upon them. These drums, seven feet diameter in the barrel by twenty feet in length, were furnished with iron cables, each link of which weighed seventy pounds, attached by a double purchase to the cradle, and regulated by two gigantic break-levers worked by blocks and pulleys, a gang of men being at hand ready to apply instantaneously on receipt of signal this powerful check to the momentum of the vessel should it be found too great.
Such were the vast preparations made to launch the Great Eastern.