INTRODUCTION TO THE CHAPTERS ON STEAM NAVIGATION—FORMATION OF THE GREAT WESTERN STEAM-SHIP COMPANY—COMMENCEMENT OF THE BUILDING OF THE ‘GREAT WESTERN’—REPORT ON SELECTION OF THE BUILDERS OF THE ENGINES (JUNE 18, 1836)—STATEMENTS OF DR. LARDNER ON THE PROBABLE FAILURE OF A LINE OF STEAM-SHIPS BETWEEN ENGLAND AND AMERICA—VOYAGE OF THE ‘GREAT WESTERN’ TO LONDON—COMPLETION OF THE ENGINES—HER RETURN TO BRISTOL—FIRE ON BOARD AND ACCIDENT TO MR. BRUNEL—VOYAGE TO NEW YORK—COMPARISON BETWEEN THE PERFORMANCES OF THE ‘GREAT WESTERN’ AND THE ‘SIRIUS’—SUBSEQUENT HISTORY OF THE ‘GREAT WESTERN’—NOTE: DIMENSIONS OF THE SHIP AND ENGINES.
IT will readily be conceded that Mr. Brunel’s railway works, which have formed the subject of the five preceding chapters, would have given him ample employment for the thirty years of his professional life.
Nevertheless, during almost the whole of that period—namely, from 1835, the year of the passing of the Great Western Railway Bill, to his death in 1859—he was also engaged in the accomplishment of undertakings which had for their object the systematic development of Ocean Steam Navigation.[116]
The ‘Great Western,’ the first steam-ship which made regular voyages across the Atlantic, the ‘Great Britain,’ the first large iron steam-ship, and the first large ship in which the screw propeller was used, and, lastly, the ‘Great Eastern,’ were Mr. Brunel’s works, built under his direction, in the midst of his other engrossing occupations, and at the sacrifice of his health and life.
The history of these projects will contain records of many disappointments as well as of success; for no great and novel undertaking can be perfected at once and without changes of plan and arrangement. As engineer to the Companies which built these steam-ships, Mr. Brunel advised the adoption of measures strongly in opposition to current popular opinion, and far bolder and more daring than even his recommendation of the broad gauge and the atmospheric system. The results obtained have verified his calculations, and the conclusions he sought to establish are now so generally accepted that it is difficult to believe that they were ever questioned. No one now has any doubt that large vessels can with safety be built of iron, or that the screw propeller can be advantageously employed in ships of war and the mercantile navy; no one can now deny that it is practicable for steam-ships to make long voyages across the ocean with regularity and speed.
A detailed account will now be given of the ships whose performances first demonstrated the truth of these propositions.
Although the ‘Great Western’ was the first steamer which was built for regular voyages between Europe and America, the first attempt to use steam in the direct voyage across the Atlantic was made by an American ship of 300 tons burden, called the ‘Savannah,’ and built at New York. Her engines were of small power, with paddles made to ship and unship. She made only two voyages to and from Europe: in the first of these she left the port of Savannah on May 25, and anchored at Liverpool on June 20, 1819.
No further advance in Ocean Steam Navigation seems to have been attempted until 1835. In the October of that year, at a meeting of the Directors of the Great Western Railway Company, at Radley’s Hotel, in Bridge Street, Blackfriars, one of the party spoke of the enormous length, as it then appeared, of the proposed railway from London to Bristol. Mr. Brunel exclaimed, ‘Why not make it longer, and have a steamboat to go from Bristol to New York, and call it the “Great Western?”’ This suggestion was treated as a joke by most of those who heard it; but at night Mr. Brunel and Mr. T. R. Guppy, one of the Directors, talked it over, and afterwards consulted three of the leading members of the Board—Mr. Scott, Mr. Pycroft, and Mr. Robert Bright. They took up the idea warmly, and a committee was formed to carry out the project.
As a preliminary measure, Mr. Guppy and Captain Christopher Claxton, R.N., made a tour of the great ship-building ports of the kingdom, in order to collect information. The results of their inquiries were embodied in a report, dated January 1, 1836, which describes at great length the advantages to be gained in large vessels. The manuscript was submitted to Mr. Brunel previously to its publication, and he inserted the following passage:—
The resistance of vessels in the water does not increase in direct proportion to their tonnage. This is easily explained; the tonnage increases as the cubes of their dimensions, while the resistance increases about as their squares; so that a vessel of double the tonnage of another, capable of containing an engine of twice the power, does not really meet with double the resistance. Speed therefore will be greater with the large vessel, or the proportionate power of the engine and consumption of fuel may be reduced.
This was an important addition to the report, for it enunciates the principle which governed Mr. Brunel in determining the dimensions and power, not only of the ‘Great Western,’ but also of the ‘Great Britain’ and ‘Great Eastern’ steam-ships.
Immediately after the publication of this report a Company was formed in Bristol called ‘The Great Western Steam-Ship Company,’ Mr. Peter Maze being the Chairman, and Captain Claxton the Managing Director. Captain Claxton’s exertions in the service of the Company from its formation to its dissolution were unremitting and invaluable. He was also, from the date of Mr. Brunel’s first connection with Bristol, one of his most intimate friends, and his confidential adviser on all points on which nautical experience was of value.[117]
Mr. Patterson (an eminent ship-builder of Bristol) was selected to superintend the building of the first ship, under the direction of a ‘Building Committee’ consisting of Captain Claxton, Mr. Guppy, and Mr. Brunel. Whenever railway business called Mr. Brunel to Bristol, which at this time was at least once in every week, the Committee and Mr. Patterson used to meet at the office, or at Captain Claxton’s or Mr. Guppy’s house, and often sat far into the night discussing the details of the design of the ship.[118]
One of the most important questions which occupied Mr. Brunel’s attention was the selection of the builders of the engines. Tenders were invited; and on receiving them, he addressed the following report to Captain Claxton, the Managing Director:—
June 18, 1836.
In considering the three tenders for the supply of marine engines for your first vessel, which you have submitted to me for my opinion, I have assumed that the interests of the company are paramount, and that all feelings of partiality towards any particular manufacturer or any local interest must yield to the absolute necessity, in this the first and the boldest attempt of the kind yet made, of not merely satisfying yourselves that you will obtain a good engine, but also of taking all those means of securing the best which in the eyes of the public may be unquestionable. In this view of the case, if you agree with me, I think you will consider that, provided the prices are fair individually, the relative amount of the tenders is a secondary consideration.
I assume, also, that the high respectability of all these parties would ensure equally from either the best materials and workmanship, and I shall confine myself simply to pointing out a few of the conditions peculiar to the engines which you require, and the means which the different parties have of complying with these conditions.
I need hardly remind you that, owing to the lateness of the season, you will require that the vessel should be prepared to run her first voyage almost immediately after the engines are fixed. You will remember, also, that it will be the longest voyage yet run; that in the event of unfavourable weather a total failure might be the result of the engine not working to its full power, or consuming too great a quantity of coals—a very common occurrence with engines apparently well made, after six or eight days’ constant work; and, lastly, that the future success of the boat as a passenger ship—nay, even of the company’s boats generally, and, to a great extent, and for some time, the reputation of Bristol as an American steamboat station, may depend upon the success of this first voyage. It is indispensable, therefore, to secure as far as possible a machine which shall be perfect in all its details from the moment of its completion. There may be time for a few trials for ascertaining the fact of its completion, but there will be none for effecting any alterations should they be found necessary, or for making any experiments. The machinery which you require to be so perfect is by no means an ordinary steam-engine.
Marine engines of 80 or 90, and even some of 100 horse-power, are mere models on a large scale of the ordinary-sized engines. Engines of 160 or 180 horse-power each would be unmanageable without many material modifications in the details; the arrangement must be different, and, as the strength of materials remains the same, the proportionate dimensions of the parts must be modified. Many contrivances of this description have been introduced into the large engines of 110 horse-power each made for the Navy. From 110 to 160 is still another and a very great stride. Those who have led the way in the first step are certainly the most likely to be aware of the difficulties of the second, and to be able to appreciate them better, and be more prepared to overcome them than those who have as yet only manufactured, however successfully, engines of the ordinary class. Of three parties tendering.... Messrs. Maudslay have made by far the largest number, and have for some years led the way in the introduction of the largest armed steamboats; and there can be no question as to the fact that they are the oldest manufacturers of marine engines, that they are themselves the originators of the greatest number of the improvements of the day, that they have made the largest engines yet made, and the greatest number of large engines of all sizes; and, lastly, that they have the principal supply of engines for the large war ships now used for the Navy, and have had hitherto the sole supply of all above 70 horse-power. With these facts before you, it remains only for you to consider how far you agree with me in the conclusion I have come to, and which I have no hesitation in expressing—that I think you will be safest, in the peculiar case of the first ship, in the hands of the parties who have had most experience, and that Messrs. Maudslay are those persons. Their price is, I think, moderate.
This report was read by Mr. Brunel at a meeting of the Board, summoned at his request; the Directors adopted his advice, and accepted the offer of Messrs. Maudslay & Field, of Lambeth.[119]
The ‘Great Western,’ for so the ship was called, had not been long commenced when a somewhat celebrated controversy arose, in which the correctness of Mr. Brunel’s views was questioned by the late Dr. Dionysius Lardner.
The circumstances which led to this discussion were as follows:—
The British Association for the Advancement of Science held its sixth meeting at Bristol in August 1836; and, as Dr. Lardner was announced to lecture on Transatlantic Steam Navigation, great interest was felt in Bristol on the occasion.
After some postponement, he delivered his lecture on August 25, to a crowded meeting of the Mechanical Section. The proceedings of the Association unfortunately do not give any report of Dr. Lardner’s observations; but, as in his latest work on the subject[120] he speaks in commendatory terms of the report given in the ‘Times’ newspaper, that account may be relied on as correct.
In the ‘Times’ of August 27, 1836, it is stated that in the course of his lecture Dr. Lardner said,—
Let them take a vessel of 1,600 tons, provided with 400 horse-power engines. They must take 2⅓ tons for each horse-power, the vessel must have 1,348 tons of coal, and to that add 400 tons, and the vessel must carry a burden of 1,748 tons. He thought it would be a waste of time, under all the circumstances, to say much more to convince them of the inexpediency of attempting a direct voyage to New York, for in this case 2,080 miles was the longest run a steamer could encounter: at the end of that distance she would require a relay of coals.
There is no detailed report remaining of the animated discussion which followed the lecture, and in which Mr. Brunel took part. He exposed several errors in Dr. Lardner’s calculations, but failed to produce any effect upon the majority of those present, who were powerfully impressed by the lecturer’s dogmatic assertions.
Those assertions seem to have had a wide circulation beyond the walls of the lecture-room; and if Dr. Lardner’s arguments were sound, and if transatlantic steamers ought to have taken their departure from ‘the most western shore of the British Isles,’ the enthusiastic advocate of a railway scheme in Ireland might well exclaim,—
The promoters of this vast object stand forewarned of defeat. Dr. Lardner, who has bestowed a great deal of pains in arguing the bearings of this undertaking, has pronounced it impracticable; and I entirely agree with him in his conclusions. The effort, nevertheless, will be made; the genius of English enterprise will hazard the consequences; and every honest spirit that shall hear of the brave British crew which will embark upon that perilous expedition will feel his heart beating high for the merchant-sailor, whom nothing can deter. He will sail; but, though dangers will encompass him, and destruction appear, there is yet a hope for his ultimate success. Let us cheer ourselves with the expectation that, as the exhausted mariner returns, he will fall in with the western shores of Ireland; that, worn out and hopeless of home and comfort upon earth, the Shannon will win him to her bosom; that, invited by the graceful sinuosities of that noble stream, and the rich and fertile lands around, he will advance to this convenient and improving city; and as he rests within its walls that he will exclaim, ‘This is the place from which I ought to have set out, for here have I returned with ease and safety!’[121]
Dr. Lardner’s views are repeated in an article in the ‘Edinburgh Review’ for April 1837 (vol. lxv.); and in the report of the proceedings of the British Association for 1836 (p. 130 of the proceedings of the sections), the reader is referred to this article, apparently as a substitute for an abstract of the lecture.
The following résumé is there given of the lecture:—
The conclusions at which he arrived were briefly these: that, in the present state of the steam-engine as applied to nautical purposes, he regarded a permanent and profitable communication between Great Britain and New York by steam-vessels making the voyage in one trip as in a high degree improbable; that since the length of the voyage exceeds the present limits of steam-power, it would be advisable to resolve it into the shortest practicable stages; and that, therefore, the most eligible point of departure would be the most western shores of the British Isles, and the first point of arrival the most eastern available parts of the western continent; and that, under such circumstances, the length of the trip, though it would come fully up to the present limit of this application of steam-power, would, nevertheless, not exceed it, and that we might reasonably look for such a degree of improvement in the efficiency of marine engines as would render such an enterprise permanent and profitable. (P. 119.)
Among other objections to long voyages the reviewer enumerates the incrustation of boilers, and the choking of smoke flues; and then, with reference to the quantity of fuel required, he proceeds:—
In proportion as the capacity of the vessel is increased, in the same ratio or nearly so must the mechanical power of the engines be enlarged, and the consumption of fuel augmented.... It is therefore demonstrable that, in the present state of steam navigation, if this voyage shall be accomplished in one uninterrupted trip, the vessel which performs it must, whatever may be her power and tonnage, be capable of extracting from coals a greater mechanical virtue, in the proportion of three to two, than can be obtained from them by the combined nautical and mechanical skill of Mr. Lang, the builder of the ‘Medea,’ and Messrs. Maudslay and Field.... That the passage from Liverpool to New York cannot on any occasion be made in one run by a steam-ship we do not maintain.... The average time of the outward voyage to New York is thirty-six days, and we say that when the circumstances of wind and water are such that a sailing vessel would require that time to make the passage, a steamer cannot make it without an intermediate supply of fuel. (Pp. 127, 139, 143.)
To sum up Dr. Lardner’s views in his own words written at about this time,[122] ‘We have as an extreme limit of a steamer’s practicable voyage, without receiving a relay of coals, a run of about 2,000 miles.’[123]
It will be seen from these extracts that the proposition Dr. Lardner laid down as the basis of his ‘demonstration’ was, that the power of the engines must be increased as the size of the vessel. Were this true his conclusion would also be true—namely, that the capacity of a given vessel regularly to accomplish a given voyage does not increase with the increase of size, since the consumption of fuel is augmented in about the same ratio.
This assumption is directly opposed to the opinion held by Mr. Brunel, and acted on by him in his recommendations to the Steam-Ship Company—namely, that while the tonnage of a ship is increased as the cube of her dimensions, the resistance is increased only about as the square.
This question was the main point at issue between Dr. Lardner and Mr. Brunel; and the proposition which Mr. Brunel then asserted is at the present time the basis of the calculations which determine the proportion between the tonnage of a steam-ship and the length of voyage she has to perform without a relay of fuel.
The history of the ‘Great Western’ steam-ship has been interrupted by this examination of Dr. Lardner’s propositions. The weight at one time attached to his opinions, the sinister influence they exercised over the early efforts of those who differed from him, and the great and enduring importance of the points at issue, have made it necessary to refer to them at length.
The ship had been steadily proceeded with, notwithstanding the adverse criticism of philosophers, and she was launched on July 19, 1837. On August 18 she left with a tug-boat for London to take her engines on board, and arrived in the Thames after a passage of four days, four-fifths of the way under sail.
When anchored in the river she was crowded with visitors, who, according to the newspapers of the day, were astonished at ‘her magnificent proportions and stupendous machinery.’
The engines were at length completed, and received in every detail Mr. Brunel’s constant supervision.
Extraordinary efforts were made to get the ship back to Bristol and to start her on her voyage across the Atlantic before the departure of the ‘Sirius’—a vessel of about 700 tons and 320 horse-power, bought by the St. George’s Steam Packet Company in order to anticipate the ‘Great Western.’
At length the ‘Great Western’ left Blackwall for Bristol, at 6.10 A.M. on Saturday, March 31, 1838, having on board Captain Claxton, Mr. Guppy, Mr. Brunel, and many other persons interested in her success. All went well at first, but at about half-past eight o’clock a very alarming fire broke out. The felt which covered the boilers had been carried up too high, and the red lead which fastened it became hot; oil gas was generated, and it burst into a fearful flame, setting fire to the beams and under part of the deck. The ship was immediately run ashore on a mud-bank not far from the Chapman Beacon, while Captain Claxton, Captain Hosken (the commander), and Mr. Pearne (the chief engineer) endeavoured to extinguish the fire.
Captain Claxton went below through the engine-rooms, and forward between the boilers to the fore-hatch, and in a stifling atmosphere of burning paint and felt he directed the nozzle of the fire-hose against the flames. While he was at work, something heavy fell on him from above. On recovering from the blow, he stooped down, and found the body of a man, who was lying insensible, with his head covered to the ears with the water which had collected on the floor. Captain Claxton called for a rope, and the almost lifeless body was hauled up. It was not till he went on deck some time afterwards that he learnt that the person who had fallen on him was Mr. Brunel, and that he had saved the life of his friend.
It appeared that Mr. Brunel was going down to Captain Claxton’s assistance by the long ladder which reached from the fore-hatch to the keelson, and put his foot on a burnt rung. He fell about 18 feet, striking an iron bar in his descent. Had he not fallen on Captain Claxton he must have struck the keelson or floor and been killed, and had not his head been raised at once he would have been suffocated by the water into which he fell. He was so severely hurt that he could not move, and he was laid on a sail on deck until the fire was extinguished, and then lowered into a boat, and landed on Canvy Island, where he remained some weeks. Although his sufferings were very great, he was able, within three days of the accident, to dictate a long letter to Captain Claxton on the state of the ship and engines.
The fire was soon got under, the ship resumed her voyage to Bristol, and anchored at Kingroad in the afternoon of Monday, April 2, to the great surprise of the good people of Bristol, who had heard that she had been burnt in the Thames. Their astonishment was increased by finding no outward signs of the disaster; but, as a fact, the deck above the boiler was charred a fourth of its thickness, and so remained till the ship was broken up.
The ‘Great Western’ started on her first voyage to New York on Sunday, April 8, at 10 A.M.,[124] and struck soundings off Newfoundland on the ninth day. She arrived at New York at 2 P.M. on Monday, the 23rd, having consumed three-fourths of the coal she had taken on board.
She found that the ‘Sirius’ had arrived before her; but under all the circumstances the palm was due to the ‘Great Western,’ for the ‘Sirius’ had left Cork eight hours before the ‘Great Western’ left Bristol (which lies a whole day’s run further from New York), and had only arrived at New York in the morning of the day in the afternoon of which the ‘Great Western’ came in; and, what is after all the most important point for comparison, the ‘Great Western’ had nearly 200 tons of coal left, while the ‘Sirius,’ when she dropped her anchor at Sandy Hook, had not only consumed all her coal, but also all the combustible articles which could possibly be thrown on the fire, including (to repeat the well-known anecdote) a child’s doll!
The ‘Great Western’ was received at New York with well-deserved honour. According to the journal of one of her passengers, ‘Myriads were collected, boats had gathered round us in countless confusion, flags were flying, guns were firing, and cheering rose from the shore, the boats, and all around loudly and gloriously, as though it would never have done. It was an exciting moment, a moment of triumph.’
The ship started on her return home on May 7, 1838, with sixty-eight passengers on board. She made the voyage in fourteen days, although twenty-four hours were lost by a stoppage at sea.
After this she ran regularly between Bristol and New York till the end of 1846. In April 1847 she was sold to the West India Mail Steam Packet Company, and became one of their best vessels.
At length in 1857 she was broken up by Messrs. Castle, of Vauxhall. Among those who went there to take a farewell of her before she finally disappeared was Mr. Brunel; thus he saw the last of his famous ship.
| Dimensions of the ‘Great Western’ Steam-Ship. | |||
| Feet | Inch | ||
| Length from fore-part of figurehead to after-part of taffrail | 236 | 0 | |
| Length between the perpendiculars | 212 | 0 | |
| Length of keel | 205 | 0 | |
| Breadth | 35 | 4 | |
| Breadth over paddle-boxes | 59 | 8 | |
| Depth of hold | 23 | 2 | |
| Draught of water | 16 | 8 | |
| Length of engine-room | 72 | 0 | |
| Tonnage by measurement | 1,340 | tons | |
| Displacement at load draught | 2,300 | " | |
| Dimensions of Engines, &c. | |||
| Diameter of cylinders | 73½ | inches | |
| Length of stroke | 7 | feet | |
| Weight of engines, wheels, &c. | 310 | tons | |
| Weight of boilers | 90 | " | |
| Water 20 tons to each boiler | 80 | " | |
| Diameter of wheel | 28 | feet | 9 inches |
| Width of floats | 10 | feet | |
COMMENCEMENT OF THE BUILDING OF THE ‘GREAT BRITAIN’—REPORT ON THE ENGINES (JUNE 13, 1839)—EXPERIMENTS ON THE SCREW PROPELLER—ITS ADOPTION IN THE ‘GREAT BRITAIN’—COMPLETION OF THE SHIP—HER VOYAGE ACROSS THE ATLANTIC—STRANDING OF THE ‘GREAT BRITAIN’ IN DUNDRUM BAY—LETTER TO CAPTAIN CLAXTON ON THE CONDITION OF THE ‘GREAT BRITAIN,’ AND ON THE MEANS TO BE ADOPTED FOR SAVING HER (DECEMBER 10, 1846)—REPORT TO THE DIRECTORS ON THE SAME SUBJECT (DECEMBER 14, 1846)—APPOINTMENT OF CAPTAIN CLAXTON TO SUPERINTEND THE EXECUTION OF MR. BRUNEL’S PLANS—LETTER TO CAPTAIN CLAXTON ON THE DIFFICULTIES TO BE OVERCOME (DECEMBER 29, 1846)—REPORT ENCLOSING CAPTAIN CLAXTON’S ACCOUNT OF THE ERECTION OF THE BREAKWATER (FEBRUARY 27, 1847)—REPORT ON THE ARRANGEMENTS FOR FLOATING OFF THE SHIP (MAY 4, 1847)—SUCCESSFUL ACCOMPLISHMENT OF THE FLOATING OPERATIONS—SUBSEQUENT HISTORY OF THE ‘GREAT BRITAIN’—NOTE: DIMENSIONS OF THE SHIP AND ENGINES.
THE Directors of the Great Western Steam-Ship Company, encouraged by the success of the ‘Great Western,’ determined shortly after her first return to England to lay down a second ship of not less than 2,000 tons burden. As they did not at that time contemplate the use of iron, a portion of the timber was purchased, and drawings were put in hand for a wooden ship. The proposed vessel was intended to be in all respects a companion ship to the ‘Great Western;’ only she was to be of larger dimensions, as it was found that additional cargo space would be remunerative.
In October 1838, Mr. Guppy (one of the Directors) communicated to the Board the results of some calculations Mr. Brunel had made relative to the cost and efficiency of iron vessels as compared with wooden ones. Mr. Brunel then suggested that Captain Claxton and Mr. Patterson, accompanied by one of his assistants, should make a voyage to Antwerp and back in the ‘Rainbow,’ an iron steam-boat of 407 tons burden, and report on the subject. On receiving their report, which was revised by Mr. Brunel, and which was strongly in favour of the adoption of iron, the Directors resolved to build their ship of that material, and of not less than 2,000 tons measurement, the same size as that which they had intended for their wooden ship. They also determined to erect the shops, and provide the tools for building her themselves.
As in the case of the ‘Great Western,’ the details of construction were settled by the Building Committee—Captain Claxton, Mr. Guppy, and Mr. Brunel—who were assisted by Mr. Patterson.
The preparation of the design occupied some time. In each succeeding drawing an increased size was proposed; at length the fifth design, showing a ship of 3,443 tons burden, was finally approved of. On July 19, 1839, the flat keel plates were laid, and the construction of the hull was commenced.
It will be necessary to enter with some detail into the history of the construction of the engines of the ‘Great Britain,’ as it has often been stated that it was on Mr. Brunel’s recommendation that the Company built their own engines. It appears, however, that Mr. Brunel repeatedly urged upon the Directors the utmost caution and economy, and that they ultimately acted ‘against his suggestion.’
When the Directors determined, in May 1838, to build a second ship, they did not entertain any idea of undertaking so great a responsibility as the manufacture of the engines; nor had they any intention of doing so, even when, towards the end of the same year, they resolved to build the ship themselves, and to construct her of iron.
The dimensions of the proposed paddle engines (for at this date the use of the screw propeller was not contemplated) were sent, in November 1838, to Messrs. Maudslay and Field, Messrs. Hall, and Messrs. Seaward.[125]
Messrs. Maudslay declined to tender, and the negotiations seem to have fallen through at the time; but they were renewed in April 1839, when estimates for engines (with cylinders of 100 inches diameter and seven feet stroke) were again invited from several makers.
The contest lay eventually between Messrs. Maudslay and Mr. Humphrys (whose patent for trunk engines was worked by Messrs. Hall). At Mr. Brunel’s desire they prepared designs for engines with cylinders of 120 inches diameter. He twice induced the Directors to postpone coming to a decision on the subject, in order that Messrs. Maudslay might mature their new patent for double-cylinder engines.
When their tender was placed before the Board, the Directors were of opinion that it largely exceeded the estimate of Mr. Humphrys. Mr. Humphrys’ estimate, however, had been more than once sent back to him for revision, at the suggestion of Mr. Brunel, who expressed doubts as to the possibility of Mr. Humphrys being able to construct his engines within the sum named by him.
Messrs. Hall stated that if they tendered for the supply of engines on Mr. Humphrys’ plan, large tools would have to be purchased by them, and the cost charged on the one pair of engines; they therefore strongly recommended the Company to become their own engine makers.
Influenced by these considerations, the Directors determined to adopt the plan of Mr. Humphrys, and to construct their own engines; and they appointed him the superintending engineer of their works.
It appears from a report by the secretary, Captain Claxton, dated March 23, 1840, that ‘previous to coming to this decision, Mr. Brunel succinctly laid before the Directors his views of the matter, and his opinion of the great responsibility they would incur if they made their own engines; and doubtless the Directors would have yielded to his suggestions, but for the report of Mr. Humphrys, showing the utter hopelessness of getting the engines made piecemeal in Bristol.’
The following is the report of Mr. Brunel on the subject:—
June 12, 1839.
At the request of Mr. Maze and Mr. Scott, whom I had the pleasure of meeting on Saturday last, I send you the following observations on the two plans and the estimates of Messrs. Maudslay, and of our Mr. Humphrys.
I have a copy of Messrs. Maudslay’s letter of the 29th ult. containing their tender, and a subsequent letter of the 11th inst. in reply to some enquiries of mine respecting their tender and Mr. Humphrys’ estimates, according to which the total cost of a pair of engines of 110 inches diameter and 8 feet stroke, upon his plan, and I presume modified as last recommended by Mr. Guppy and myself, including boilers and fixing on board, would be 29,296l., or, as stated by Captain Claxton in a letter to me of the 1st inst., 30,700l.
First, as to the comparative merits of the plans, I consider them both excellently adapted to our particular case, and that the choice will depend upon other circumstances than the construction of the engines, and these circumstances, I consider, would be, the relative cost and the advantages of forming an establishment which will eventually become necessary for the repair and maintenance of our engines, contrasted with all the advantages to be derived from the responsibility and experience in all the details of a first-rate manufacturer, and to which I attach very great value, particularly in the early proceedings of a Company like ours. As regards the cost, I understand Messrs. Maudslay’s tender to be for an engine of four 75-inch cylinders, which is equal to a pair of ordinary engines of about 106 inches.
| Engine, boiler, and paddle-wheels, fixed on board, supposing the vessel in London, and with reduced size of boiler, | £ 41,400 |
| Deduct allowance for coal-boxes and combings for hatchways as proposed by Messrs. Maudslay, | 500 |
| 40,900 | |
| Additional expense incurred by Messrs. Maudslay in consequence of the engines being fixed on board at Bristol instead of London, I estimate at, | 250 |
| Total amount to be paid Messrs. Maudslay, | 41,150 |
| In addition to this will be the freight and insurance, which we are to pay, and also the unloading at Bristol and placing in the vessel, which I take at Captain Claxton’s estimate, | 2,000 |
| Making a total of | 43,150 |
It is to be observed that this includes Mr. Field’s apparatus for changing water, Kingston’s cocks, casing the cylinders, and all those extras which were applied to the ‘Great Western,’ and also the paddle-beams and paddle-wheels. Without these latter the nett cost of the engine, fixed in place, and including all other extras, would appear to be about 40,000l. or 40,500l. If the cylinders be increased to 77¾, which would be equivalent to the pair of 110 inch, and supposing the cost of the engines to increase in the same ratio as the power resulting from this increase, but which ought not to be the case, the total cost, according to Messrs. Maudslay’s estimate, will be 46,500l., and deducting the paddle-beams or framework for carrying the paddles, which do not, I think, form part of Mr. Humphrys’ estimate, probably about 45,500l. as compared with Mr. Humphrys’ estimate of 30,700l. With respect to this latter estimate, I cannot help expressing the fears I entertain that Mr. Humphrys is over-sanguine, and that the cost would greatly exceed the sum named. The items seem to me to be moderate prices only for each article named, and I see no allowance for those alterations, damages, and waste of parts, and a variety of other contingencies, which in a piece of machinery of this magnitude and novelty is certain to amount to a very large sum.
In his estimate of the fittings and smaller parts, I think also he has greatly underrated them.
The outlay for tools and tackle would, I think, also be greater than he seems to anticipate, and on the whole I cannot but come to the conclusion in my own mind, and I should not act rightly if I did not communicate that opinion to you, that the first outlay will be fully as large and probably larger by adopting the plan of making our own engines than by employing a manufacturer. It is true we shall have some valuable and costly tools and shops included in this outlay, and a fine establishment formed, which may be rendered fully competent in point of means to continue the manufacture of engines for others, and to keep up the repairs of any number of engines which the Company are likely to have at work. My only fear would be that of the risk of the undertaking being too great for a newly-formed establishment. The making of the vessel itself is no mean effort, and to superadd the construction of the largest pair of engines and boilers yet made, and upon a new plan, is calculating very much upon every effort being successful, and particularly upon the continued assistance of those who have hitherto attended to the subject; as it must be well known to the Directors that if Mr. Guppy, for instance, should be prevented from giving his time as he has hitherto done, or if Mr. Humphrys should, from illness or other causes, leave us, the manufactory would be brought to a stand, and the loss would be serious. I have no wish to deter the Company from becoming their own manufacturers—I think it a course which must ultimately be adopted if the Company thrive—but I should have much preferred that it had been adopted gradually, that we had commenced with a vessel, and then proceeded with boilers and repairs; and, as our establishment became formed and matured, and when we might no longer depend entirely upon the engineering talents and assistance of one Director, who may be unable to attend to it, or upon the health of one superintendent who, as yet, is alone in possession of all our plans and ideas, and at present is alone capable of carrying them out, we might then have ventured upon making the engines perhaps for the third vessel. Circumstances may, however, render it necessary that we should proceed more expeditiously, and I am only anxious that the Directors should be aware of the difficulties that we may have to encounter, and that they should not form expectations as regards economy in which they may be disappointed. The result of the best consideration I have been able to give to it is, that the question does not seem to be one of cost. In that respect, according to my view, the two modes of proceeding would be nearly balanced, but it resolves itself into the following question:—Is it better in our present position to enter at once upon the manufacture of the engines and boilers, in doing which we shall in part repay the cost of tools and shops, which must eventually be required, and by which we shall be more independent, and more capable of expediting the works, should it become desirable to incur any additional expense for that purpose, or to throw all the responsibility and risk on another party or contractor—the vessel, for which we could not easily contract, being still made in the Company’s yard?
I have thus reduced the question to that state in which I can offer no further opinion or advice; it is now for you to determine. The question is one which has frequently to be decided upon by the Directors of public works; it is very much a matter of feeling, but it is simplified in the present instance by the circumstance that the expense in either case will be, to my view at least, about the same, and the work, I have no doubt, equally good in either case.
Upon this point, as perhaps upon the subject of cost, I have no doubt there will be some difference of opinion. It will be said that the work done under our own superintendence can be more relied upon than the work of a manufacturer, and that even in the engines of the ‘Great Western’ steam-ship, coming from one of the most experienced manufacturers, many defects may be pointed out.
I should agree fully with both these arguments, but I think these advantages are fully counterbalanced by that of the experience in all the details which is brought into operation in an old-established manufactory, and the great relief from responsibility and risk obtained by contracting for the whole work.
The Directors having determined to make the engines, erected shops and fitted them up with proper tools. The services rendered to them by Mr. Brunel at this period were fully acknowledged at the next meeting of the shareholders.[126]
Mr. Brunel’s attention was now anxiously devoted to the consideration of the numerous questions involved in the construction of the ship and her engines; and, in order to obtain reliable information on many points, he sent one of his assistants, Mr. Berkeley Claxton, in the ‘Great Western.’ His sole occupation during six voyages was to note the amount of rolling and pitching, and the exact performance of her engines, with the effect of the use of the expansion valves on her speed, and on the consumption of fuel. These reports furnished Mr. Brunel with information which was of great value, especially when, shortly afterwards, he advised the Directors to adopt the screw propeller instead of paddlewheels.
The circumstances which led to the adoption of the screw propeller in the ‘Great Britain’ instead of paddlewheels were as follows:—
In the early part of the year 1840, the performances of the ‘Archimedes’ steamer began to attract the attention of scientific men. This vessel, which was fitted with the screw propeller patented by Mr. Francis Pettitt Smith, arrived at Bristol in May. A few trips were made up and down the Float, but the advantages of the screw propeller were not fully appreciated by those to whom they were explained.
But Mr. Guppy, who had attended some of these trials, went round in the ship to Liverpool. On his return he made a report to the Building Committee, and the Directors, on Mr. Brunel’s advice, passed a resolution delaying the progress of the engines of the ‘Great Britain,’ and of those parts of the frame which would be affected by any change of plans. Mr. Brunel was also requested by them to give his attention to the question of the adoption of the screw, and to report thereon.
During the next three months experiments were made by Mr. Brunel, assisted by Mr. Guppy and Captain Claxton, on the screw propeller in the ‘Archimedes.’[127] These experiments afforded ample opportunity of trying the performances of several forms of screws.[128]
On October 1, Mr. Brunel attended a special meeting of the Board, and read and explained a report he had drawn up, in which he laid before the Directors at great length the results of the different experiments he had made, and the advantages which he believed would attend the use of the screw propeller.[129] A resolution was passed adopting it for the ‘Great Britain.’
Mr. Brunel at first thought that he would be able to retain the form of engines which had been originally determined on for working the paddle wheels; but, on consideration, this was found impracticable. As the Company had by this time erected complete engine works, there could now be no question as to their undertaking the construction of the new description of engines required for working the screw propeller.[130]
Mr. Humphrys resigned the post of superintendent of the works, and Mr. Harman was appointed assistant engineer under Mr. Guppy, to whom the Directors, on the advice of Mr. Brunel, entrusted the supreme control of their manufacturing establishment.
The duties and responsibilities which devolved on the Building Committee—Captain Claxton, Mr. Guppy, and Mr. Brunel—were most arduous. To design and construct a steam-ship larger than any that had, up to that time, been launched, to make this ship of a material which had but lately been introduced into shipbuilding, and which had never before been employed on a large scale, to adapt to this ship a novel form of propeller which had not previously been used save in a merely experimental steamer, and to build in a newly opened manufactory marine engines of a much greater size than any that had hitherto been contemplated, and of a totally different character, was indeed a bold enterprise. Mr. Brunel had, as has been shown, recommended the Company not to undertake one part of the work, that, namely, of the manufacture of the engines, which he thought would have been better entrusted to the most experienced engine builders. But although the Directors had acted contrary to his advice, this circumstance in no way diminished the zeal with which he and his coadjutors entered upon their task.
A short statement of the principal dimensions of the vessel and engines is given in a note to this chapter; but some of the more remarkable features in the design may be mentioned here.
In the construction of the ‘Great Britain,’ the same care which had been spent in securing longitudinal strength in the wooden hull of the ‘Great Western,’ was now given to the suitable distribution of the metal. Over the transverse angle iron ribs at the bottom of the ship were laid ten deep longitudinal beams (see woodcut, fig. 13, a), which, over the greater part of the bottom of the ship, were covered with an iron deck (b) riveted to their upper edges by angle irons, thus forming a cellular structure which added greatly to the strength of the ship. It does not appear that this deck was designed to be watertight, so that it did not form the same security against accident as the inner skin of the cellular structure which Mr. Brunel afterwards adopted in the ‘Great Eastern.’
The upper part of the sides of the ship, in the middle of her length, were carefully designed so as to give her longitudinal strength. The side plates were thickened, and were riveted to iron shelf-plates three feet broad (c); and two bands of iron, six inches wide and one inch thick, with the joints strengthened, ran along the top of the ship’s side. There were bands of iron riveted to the shelf-plate, and iron deck beams crossed diagonally under the planking of the upper and main decks. Also at the junction of the ship’s side with the shelf-plate there ran longitudinally a tie of Baltic pine timber, 340 square inches in section (d); this being well secured to the shelf-plate and ribs, added considerably to the strength of this portion of the hull.
The ship had five watertight bulkheads, and was thus separated into six compartments.
Scale of feet. Fig. 13. ‘Great Britain’ Steam-Ship. Transverse Section.
Fig. 13. ‘Great Britain’ Steam-Ship.
Transverse Section.
She had no keel, as there did not appear to be sufficient advantage gained by such an appendage to make up for the increase of the ship’s draught by the amount of the depth of the keel. There were two side or bilge keels (e), reaching down to the level of the keel plate of the ship, so that when grounded in dock she might rest on three points in her width.
The ‘Great Britain’ had what is termed a balanced rudder, a portion of the rudder (in this case about one third) being in advance of the pivot on which it turned. The result of this arrangement was that, the pressures on either side of the pivot nearly balancing one another, there was no difficulty in putting the helm over rapidly. This rudder was knocked away when the ship ran ashore at Dundrum, and was subsequently replaced by an ordinary rudder.[131]
In the construction of the hull of the ship, instead of a mere imitation of the arrangements of the timber in wooden ships, the proper distribution of the material to receive the strains that would come upon it was carefully considered. In the result, the ship contained, in the structure of her bottom, bulkheads, deck shelves, and longitudinal kelsons, the longitudinal principle of construction which Mr. Brunel afterwards so fully developed in the ‘Great Eastern.’
Apart from their size, the design of the engines of the ‘Great Britain’ necessarily presented many peculiarities. The boilers, which were six in number, were placed touching each other, so as to form one large boiler about thirty-three feet square, divided by one transverse and two longitudinal partitions. This boiler, which was fitted in between the longitudinal bulkheads of the ship, had a double set of furnaces, and therefore of stoke-holes, one at the fore end, and the other at the after end, next the engine room.
It would seem that the boiler was only worked with a pressure of about eight pounds on the square inch.
The feed water for the boiler was passed through a casing surrounding the funnel, in which it was heated before passing into the boiler. This casing was open at the top, and the water flowed thence into the boiler by gravitation. A similar arrangement was adopted by Mr. Brunel in the ‘Great Eastern.’
The condensers were made of wrought iron, being in fact part of the frame of the ship. The main shaft of the engine had a crank at either end of it, and was made hollow, a stream of water being kept running through it so as to prevent heating in the bearings. An important point in the design was the method by which the motion was transmitted from the engine-shaft to the screw-shaft, for the screw was arranged to go three revolutions to each revolution of the engines. Where the engines do not drive the screw directly, this is now universally effected by means of toothed gearing; but, when the engines of the ‘Great Britain’ were made, it was thought that this arrangement would be too jarring and noisy. After much consideration, chains were used, working round different-sized drums with notches in them, into which fitted projections on the chains. The greater part of the length of the screw-shaft consisted of a hollow wrought-iron boiler-plate tube, the metal being thus very advantageously placed for taking torsional strain, and the shaft was in this way made very light. The engines were designed to work expansively, the steam being cut off at one-sixth of the stroke.
The completion of the ‘Great Britain’ was delayed many months, owing to the financial difficulties in which the Great Western Steam-Ship Company had become involved; the profit on working the ‘Great Western’ having been seriously diminished in consequence of the competition of the Cunard steamers.
At length, however, the ship was finished; and she was floated out of dock into the Floating Harbour on July 19, 1843, in the presence of His Royal Highness Prince Albert.
This seems a fitting place to insert the following letter from Mr. Brunel to Mr. Guppy, written at the beginning of August 1843:—