Admiralty, Mr. Brunel’s connection with the, respecting the screw propeller, 283.
Communication with the, on floating gun-carriage, 459
Airy, G. B., Astronomer Royal, member of the Gauge Commission, 117.
Correspondence with Mr. Brunel on astronomical observations for the ‘Great Eastern,’ 321
Angarrack, viaduct at, 189
‘Archimedes’ steamer, the screw propeller used in the, 253.
Experiments made in the, 254
Armstrong, Sir W. G.
His hydraulic machinery at Paddington station, 85 _note_.^{1}
Engaged with Mr. Brunel on gunnery investigations, 452.
Letter to, 454, 461
Atlantic cable expeditions of the ‘Great Eastern,’ 412.
Loss of the first cable, 412.
A second one laid, and the first recovered, 413.
The French cable of 1869, 413
Atmospheric system of propulsion on railways, 131.
Description of this method of traction, 134.
History of its introduction prior to 1844, 136.
Mr. Brunel’s views respecting it, 137.
His report recommending its adoption on the South Devon Railway, 138.
Grounds of his recommendation, 142.
Select Committee on, 144.
Working of the system, 153.
Imperfections of engines, 154, and longitudinal valve, 157.
Mr. Brunel’s report on the failure of the Atmospheric apparatus, 159.
Abandonment of the system, 164
Australian Mail Company, Mr. Brunel appointed engineer of the, 290
Barlow, Professor P., member of the Gauge Commission, 117
Barlow, W. H., 57
Bath, station at, 84
Bath, bridges at, 175, 179
Bathford, bridge at, 175
Beamish, Richard, his account of Sir Isambard Brunel’s block machinery at Portsmouth, quoted, 3.
Joins the Thames Tunnel works, 21
Bennett, Joseph, Mr. Brunel’s secretary, 92
Berks and Hants Railway, 88
Birmingham and Oxford Junction Railway, 90
Birmingham, Great Western extension to, 124
Birth of Mr. Brunel, 1
Blake, H. W., consulted by Mr. Brunel on the ‘Great Eastern,’ 297
Block machinery at Portsmouth, Sir Isambard Brunel’s, 2
Bourbon, Ile de, Sir Isambard Brunel’s suspension bridges for the, 5.
Description of them, 40
Bourne viaduct, 181
Box Tunnel, 70 _note_^{1}, 72, 81.
Criticism as to its safety, 81.
Letter from Mr. Brunel on the, 81
Bremner, A., 263, 280
Brentford, dock at, 440
Brentford, extension of the Great Western Railway to, 86
Brereton, Robert Pearson, chief of Mr. Brunel’s engineering staff, 92, 210, 215 _note_^{1}, 217 _note_^{1}, 223, 225, 437, 438 _note_^{1}
Brickwork, use of, 59.
Bridges in, 172
Bridges, suspension, Sir Isambard Brunel’s: in the Ile de Bourbon, 5, 40; designs for the Serpentine, and for the Thames at Kingston, 5.
Mr. Brunel’s: at Clifton, 46; Charing Cross, 59
Bridges, railway, 171.
1. Brickwork and masonry bridges, 172.
Flying bridges, 176.
Skew bridges, 177.
Letter from Mr. Brunel on bridge construction, 178.
2. Timber bridges and viaducts, 179.
3. Cast-iron bridges, 190.
4. Wrought-iron bridges, 192.
Girder bridges, 193.
Opening bridges, 195.
Trussed bridges, 199.
Extracts from letters on bridges of large span, 212 _note_^{1}.
Experiments on matters connected with bridge construction, 227
Bristol, Mr. Brunel’s early connection with, 58, 64.
Station at, 84.
Bridges at, 175, 195.
Floating Harbour, 422.
Proposed improvement of the port, 426.
New lock at, 427
Bristol and Exeter Railway, 86
Bristol and Gloucester Railway, 90
Bristol and South Wales Union Railway, 90
Briton Ferry Docks, 437
Broad Gauge. _See_ Gauge
Brunel, Sir Marc Isambard, birth of, 2.
Arrives in England, 2.
Marries Miss Sophia Kingdom, 2.
Designs the Block machinery at Portsmouth, 2.
Veneering machinery, 5.
Shoe machinery, 5.
Designs suspension bridges for the Ile de Bourbon, 5, 40.
Experiments on carbonic acid gas, 5, 42.
Proposes the Thames Tunnel, 5.
Extracts from his Journal relating to the Rotherhithe shaft, 10.
Extracts from his Journal relating to the works at the Thames Tunnel up to January 1828, 16.
His death, 39.
Hoop iron introduced by, in brickwork, 177.
Designed a large timber bridge to cross the Neva, 211 _note_^{2}
Bullo Pill opening bridge, 197
Caermarthen, opening bridge at, 198
Carbonic acid gas, experiments on, by Sir Isambard Brunel and Mr. Brunel, 5, 42
Cast-iron bridges, 190.
Mr. Brunel’s views as to the use of cast iron in bridge construction, 190, 192
Cheltenham and Great Western Union Railway, 88
Chepstow bridge, 203.
Mode of forming piers, 203.
Description of superstructure, 206.
Floating and erection, 209
Clarke, Seymour, 117
Claxton, Captain, 57.
Assists Mr. Brunel at the floating of the Chepstow bridge, 210.
And the Saltash bridge, 222.
Appointed Managing Director of the Great Western Steam-Ship Company, 234, 242, 247.
Letter to, from Mr. Brunel, on the ‘Great Britain,’ 264.
Goes to Dundrum to carry out Mr. Brunel’s plans for the protection of the ‘Great Britain,’ 272.
Letter to, from Mr. Brunel, on the breakwater, 272.
Report of, on breakwater, 274.
Superintends floating of the ‘Great Britain,’ 280.
Consulted by Mr. Brunel on the ‘Great Eastern,’ 291, 297.
Floating Harbour, Bristol, 424
Clifton Suspension Bridge, origin of the, 47.
Mr. Brunel’s designs, 47.
Rejected by Mr. Telford, 51.
Mr. Telford’s own design, 52.
Second competition, 52.
Mr. Brunel successful, and appointed engineer, 53.
The site described, 54.
Description of the design, 55.
Architectural features, 56.
Commencement of the work, 56.
Completed, 57
Coles, Captain Cowper, 461
Construction of works, letter on, 178
Continuous girders, 208
Cork and Youghal Railway, 91
Cornwall Railway, 87.
Viaducts on, 185
Crystal Palace at Sydenham, water-towers of the, 448
Cylinders, of Chepstow bridge, method of sinking the, 204.
The great cylinder of the Royal Albert Bridge, 214
Dalkey Railway, Atmospheric System on, 131
Dartmouth and Torbay Railway, 87
Death of Mr. Brunel, 520
Dock and pier works:
Monkwearmouth, 418;
Bristol, 422;
Plymouth, 433;
Briton Ferry, 437;
Brentford, 440;
Neyland, 443
Draught, Mr. Brunel’s paper on, 101 _note_^{1}
Dublin, railway to Wicklow from, 91
Dundrum Bay, stranding of the ‘Great Britain’ in, 263
Early life of Mr. Brunel.
He goes to school at Chelsea, 4; at Brighton, 4; at Paris, 5.
Employed in his father’s office, 5.
Engaged at the Thames Tunnel, 6.
References by Sir I. Brunel to his exertions, 17, 19, 21, 22, 25, 33.
Appointed resident engineer, 25 _note_^{1}.
First irruption of the river, 29.
Second irruption, 35.
Accident, 36.
Visit to Plymouth, 46
Eastern Bengal Railway, 91, 195, 517
Eastern Counties Railway, gauge adopted on the, 105
Eastern Steam Navigation Company, formation of the, 291.
_See_ ‘Great Eastern’
Egypt, visit to, 517
Electric telegraph, application of the, in connection with railways, 155
Engineer, Mr. Brunel’s view of the position of, 475.
Of joint-engineer, 476.
Of consulting engineer, 477.
Of the position of the engineer in relation to the contractors, 477.
To the Directors, 478.
Remarks on interference of Directors with assistant engineers, 481.
On State control over engineering works, 486
Experiments:
Strength of timber, 182, 227.
Cast-iron girders, 190, 191.
Wrought-iron girder, 193.
Riveting, 194, 228.
Continuous beams, 209, 229.
Bridge construction, 227.
Ropes and chains, 228.
Friction, 348, 368, 385
Faraday, M., his experiments on the liquefaction of gases, 42.
Consulted by Mr. Brunel on the Kyanising process, 189
Field, Cyrus, 411, 414
Field, J., consulted by Mr. Brunel on the ‘Great Eastern,’ 297
Floating gun-carriage, 454
Floating harbour at Bristol, 422
Floating pier, proposed at Portishead, 426.
In Mill Bay, 436
Florence and Pistoja Railway, 91
Flying bridges, 176
Ford, Captain Robert, consulted by Mr. Brunel on the ‘Great Eastern,’ 297
Friction, experiments and observations on, 348, 368, 385
Froude, W., letter to, describing floating of the ‘Great Eastern,’ 389
Gathampton, bridge at, 174
Genoa, Novi, and Alessandria Railway, 91
Gauge of railways, difference between the broad and narrow, 99.
Origin of the ordinary gauge, 99.
Adoption of the broad gauge on the Great Western Railway, 101, 106.
Reasons for its adoption, 102.
Attacks on, 106.
Reports of Mr. Wood and Mr. Hawkshaw on, 107.
Report by Mr. Brunel on, 107.
Northern extension, 116.
Inconveniences of a break of gauge, 116.
Royal Commission on the gauge question, 117.
Report of the Commissioners, 117.
‘Observations on the Report,’ 119.
Report of the Board of Trade, 122.
Act for regulating gauge, 122.
The mixed gauge, 124.
Summary of the advantages of the broad gauge, 127.
Partial abandonment of the broad gauge, 127, 129.
Report on the broad gauge, 525
Gilbert, Davies, appointed referee in the second competition for the Clifton Suspension Bridge, 52.
Recommends Mr. Brunel’s design, 53
Girder bridges, 193
Glennie, W., 215 _note_^{1}
Gloucester, opening bridges near, 196
Gloucester and Dean Forest Railway, 88
Gooch, Sir Daniel, 117, 119.
Experiments by, 125
Gravatt, William, an assistant engineer at the Thames Tunnel, 26
‘Great Britain’ steam-ship, commencement of the, 247.
Report on the engines, 249.
Adoption of the screw propeller, 254.
Principal features of her design, 255.
Arrives in the Thames, 261.
Her voyages, 262.
Stranded in Dundrum Bay, 263.
Letter from Mr. Brunel on the subject, 264.
His reports to the Directors, 267, 273.
Construction of breakwater, 274.
Floating of the ship, 280.
Her subsequent history, 282.
Dimensions of ship and engines, 282
‘Great Eastern’ steam-ship, origin of the project, 291.
Memorandum by Mr. Brunel to the Directors of the Eastern Steam Navigation Company, 292.
He is appointed engineer, 293.
Letter on the form and dimensions of the ship, 294.
Report on mode of proceeding, 296.
On enquiries relating to the draught and form of the vessel, 297.
On the dimensions, 299.
Tenders invited, 300.
Report on tenders, 301.
Commencement of the work, 304.
Extracts from Mr. Brunel’s memoranda, 304, 310.
Letters on his position as engineer, 311.
Report describing the ship, 315.
Letter to the Astronomer Royal, 321.
The observers’ department in the ship, 322.
Captain Harrison appointed to the command, 323.
Memorandum on the management of the ship, 324.
Letter on the duties of chief engineer, 335.
Suspension and resumption of the works, 339.
Reasons for launching the ship broadside to the river, 340.
Adoption of iron sliding-surfaces, 343.
The ways and cradles, 345.
Motive power, 348.
Checking gear, 351.
River tackle, 352.
Letter to Captain Harrison on the river tackle, 354.
Letter to the Directors respecting the operation of launching, 355.
Memorandum of arrangements and intended mode of proceeding, 356.
Particular instructions, 358.
Final preparations, 359.
Commencement of the launch, 360.
Accident at one of the drums, 361.
Failure of the first attempt, 362.
Second attempt, 364.
Report on operations, 366.
Progress of the launch, 368.
Suspension of operations, 376.
Report and memorandum, 377.
Re-commencement, 379.
Floating of the ship, 382.
Experiments and observations on friction, 385.
Letter to Mr. W. Froude, describing the floating, 389.
Formation of the Great Ship Company, 393.
Progress of the works to Mr. Brunel’s last illness, 393.
Completion of the ship, 393.
Voyage to Weymouth, 393.
Explosion of water-heater, 393.
Storm at Holyhead, 395.
Description of the ship, 396.
Her first voyages to New York, 403.
To Quebec, with troops, 404.
Accident to rudder, and loss of paddlewheels, 405.
Voyages in 1862, 407.
Accident off Montauk Point, 407.
Formation of Great Eastern Steam-Ship Company, 409.
Remarks on performance of ship, 409.
Employed in laying Atlantic cables, 412.
The Indian cable, 414.
Dimensions of ship and engines, 416
Great Exhibition of 1851, Mr. Brunel’s opinion respecting prizes to exhibitors, 445.
His part in the work of the Building Committee, 446.
Supports Sir Joseph Paxton’s design, 447
Great Western Hotel, 86
Great Western Railway, origin of the, 63.
Mr. Brunel appointed engineer, 64.
Survey of the country, 65.
Bill for a line from London to Reading, and Bath to Bristol, read a second time, and referred to a committee, 66.
Opposition to the Bill, 67.
Plan of entering London, 68.
Mr. Brunel’s cross-examination, 69.
The Bill passed by the Commons, but thrown out in the Lords, 70.
A Bill for the whole line introduced, read a second time, and committed, 71.
Evidence taken before the Commons’ Committee, 72.
Evidence before the Lords’ Committee, 73.
The Bill receives the Royal Assent, 74.
Construction of the line, 80.
Opening from London to Bristol, 80.
Levels and inclines, 80, 104.
The Box Tunnel, 81.
The Bath and Bristol stations, 84.
Paddington station, 84.
Branches and extensions of the railway, 86, 88, 90.
Adoption of the broad gauge, 106.
The permanent way, 108, 111.
Meeting of shareholders on broad gauge, 111.
Extension of the Great Western system, 116
‘Great Western’ steam-ship, formation of the company, 233.
Details of the construction of the vessel, 234 _note_^{2}.
Report on the selection of the builders of the engines, 235.
Controversy with Dr. Lardner, 237.
Launch of the vessel, and voyage to London, 241.
Return to Bristol, 242.
Fire on board, and accident to Mr. Brunel, 242.
First voyage to New York, 243.
Subsequent history, 244.
Dimensions of ship and engines, 245
Gunnery experiments, 452
Guppy, T. R., 148, 233, 234, 247, 253, 254.
Letter to, on iron-ship building, 259
Hammond, J. W., 65, 92
Hanwell, bridge at, destroyed by fire, 190
Hanwell viaduct, 172
Harrison, Captain, 223.
Appointed commander of the ‘Great Eastern,’ 323.
Letter to, on the river tackle, 354.
At the launch, 362, 370, 382, 392
Haverfordwest, opening bridge at, 198
Hawkshaw, J., 57.
Report on broad gauge and permanent way, 107
Henley branch of the Great Western Railway, 86
Hungerford Suspension Bridge, 57, 59
India, railway works in, 91
Indian Cable expedition of the ‘Great Eastern,’ 414
Institution of Civil Engineers, 516 _note_^{2}, 521
Inventors, communications with, 485
Ireland, railway works in, 90
Italy, Mr. Brunel’s railway works in, 91, 510
Ivybridge viaduct, 182
Kennet, bridge over the river, 175
Kidwelly, opening bridge at, 198
Kyanising process, 189, 421
Landore, viaduct at, 183
Lane, Michael, 29
Lardner, Dr., 114 _note_^{1}.
Opinions respecting ocean steam navigation, 237
Llansamlet, flying arches near, 176
Llynvi Valley Railway, 89
Locke, Joseph, 62, 74.
His address on the death of Mr. Brunel, 521
Locomotive power, comparison of, with stationary power, 142, 166
Loughor, opening bridge at, 197
Maidenhead bridge, 96, 173
Masonry, bridges in, 172
Maudslay and Field, 15, 148, 236, 284
Milford Haven, 88, 443
Monkwearmouth, docks at, 417, 418
Moulsford, bridge at, 174
Nasmyth, James, his steam hammer designed, 252 _note_^{1}.
Letter to, on gunnery experiments, 452
Neath, improvement of river, 438 _note_^{1}
Newport viaduct, 185, 199
Neyland, pier at, 443
Ocean steam navigation, Mr. Brunel’s connection with, 231, 313
Opening bridges, 195
Oxford, Mr. Brunel created a Doctor in Civil Law at, 516
Oxford and Rugby extension of the Great Western Railway, 90, 116
Oxford branch of the Great Western Railway, 86
Oxford, Worcester, and Wolverhampton Railway, 90, 116
Paddington station, 84
Paris Exhibition of 1855, letter on decorations conferred at, 489
Parkes, Dr., medical superintendent of Renkioi Hospital, 468.
Report of, on hospital buildings, 468
Patent laws, Mr. Brunel’s opinions on the, 212 _note_,^{1} 450, 451, 454, 485, 489, 497
Patterson, W., 234, 247, 263
Paxton, Sir Joseph, his design for the Great Exhibition building, 447
Permanent way on the Great Western Railway, 108, 535
Plymouth Great Western Docks, 433
Polygonal rifle, 449
Portishead, proposed pier at, 426
Prince Consort, H.R.H. the, opens the Royal Albert Bridge, 226.
Present at floating of the ‘Great Britain,’ 259
Private life of Mr. Brunel, 499.
Early reminiscences, 500.
Removal to Duke Street, and marriage, 505.
His taste in art, 506.
First journey to Italy, 508.
Half-sovereign accident, 511.
Purchase of property in Devonshire, 514.
Life at Watcombe, 515.
Failing health, 516.
Journeys to Switzerland and Egypt, 516.
Letter from Philæ, 517.
His last illness, 520
Quaker’s Yard, viaduct at, 89
Railways, sketch of, in England prior to 1833, 61.
Extent of Mr. Brunel’s, 79.
Great Western, 80.
Branches to Oxford, 86.
Windsor, 86.
Wycombe, 86.
Uxbridge, 86.
Henley, 86.
Brentford, 86.
Bristol and Exeter Railway, 86.
South Devon, 87.
South Devon and Tavistock, 87.
Cornwall, 87.
Branch lines now incorporated with Great Western Railway:
Berks and Hants, 88.
Wilts and Somerset, 88.
Cheltenham and Great Western Union, 88.
Gloucester and Dean Forest, 88.
The South Wales, 88.
The Taff Vale, 89.
The Vale of Neath, 89.
The Llynvi Valley, 89.
The South Wales Mineral, 89.
Bristol and South Wales Union, 90.
Bristol and Gloucester, 90.
The Oxford and Rugby, 90.
Birmingham and Oxford Junction, 90.
Oxford, Worcester, and Wolverhampton, 90.
Ireland, 90.
Italy, 91.
India (Eastern Bengal), 91
Railway Structures, letter on the Royal Commission on the Application of Iron to, 192, 486
‘Rattler’ steam-ship, trials with the, 287
Rendel, J. M., 211, 433
Renkioi, hospital buildings at, 461.
Description of the buildings, 463.
Dr. Parkes’s report on the formation and general management of the hospital, 468
Rennie, G. and J., 148
Richards, Westley, letters to, on polygonal rifle, 450
Riveting, experiments on, 194, 228
Ropes and chains, experiments on, 228
Rotherhithe shaft of the Thames Tunnel, construction of the, 9
Royal Albert Bridge at Saltash, 211.
Plans for crossing the river Tamar at Saltash, 211.
Trial cylinder for centre pier, 213.
Report on making bridge for a single line, 214.
Mode of construction of centre pier, 214.
Description of superstructure, 218.
Floating of first truss, 221.
Lifting of first truss, 224.
Floating and lifting of second truss, 225.
Opening by H.R.H. the Prince Consort, 226
Royal Society, 516 _note_^{1}
Russell, J. Scott, builds the ‘Victoria’ and ‘Adelaide,’ 290.
Assists Mr. Brunel in maturing designs of the ‘Great Eastern,’ 291, 292, 297.
Letter to, on the form and dimensions of the ship, 294.
Tender accepted for hull and paddle-engines, 301
St. Mary’s viaduct, 181
St. Pinnock viaduct, 186
Saltash bridge. _See_ Royal Albert Bridge
Samuda, J., 131, 134, 148, 160
Saunders, C. A., 92, 117, 119
Screw propeller, the, adopted for the ‘Great Britain,’ 254.
Communications on, with the Board of Admiralty, 283.
Trials with the ‘Polyphemus,’ 284.
With the ‘Rattler,’ 287.
Report recommending adoption of, 539
Shield, Thames Tunnel, the, 11, 12
‘Sirius’ steam-ship, 241
Skew bridges, 177
Smith, F. P., the screw propeller, 253, 287.
Consulted by Mr. Brunel on the ‘Great Eastern,’ 297, 298
Smith, Sir F., member of the Gauge Commission, 117
Smyth, C. Piazzi, Astronomer Royal for Scotland, correspondence with Mr. Brunel on astronomical instruments for the ‘Great Eastern,’ 322
Sonning Cutting brickwork bridge, 175.
Timber bridge, 179
South Devon and Tavistock Railway, 87.
Viaducts, 188
South Devon Railway, 87.
Course of the line, 132.
Atmospheric System adopted on the, 138.
Viaducts, 182
South Wales Mineral Railway, 89
South Wales Railway, 88.
Viaducts, 183, 194
Standard drawings, 172 _note_^{2}
Stationary and locomotive power, comparison of, 142, 166
Statue of Mr. Brunel, 520 _note_^{1}
Stephenson, George, 61, 62, 70, 74, 99
Stephenson, Robert, 62, 106, 107, 134
Atmospheric System, 136, 137 _note_^{1}, 138, 144.
Conway and Britannia bridges, 221, 223.
Launch of the ‘Great Eastern,’ 375, 376, 377, 378, 384 _note_^{1}, 485, 516, 517, 521
Stonehouse viaduct, 181
Taff Vale Railway, 89, 104 _note_^{1}
Tamar, plans for crossing the river, 5 _note_^{2}, 46, 211
Telford, T., appointed referee to decide upon the plans for the Clifton Suspension Bridge, 51.
Rejects Mr. Brunel’s plan, 51.
Designs one himself, 52.
His plan described, 52
Thames Tunnel, project of, first occupies Sir Isambard Brunel’s attention, 5.
Plans suggested for the construction of a tunnel, 6.
Borings, 7.
Remarks on borings, 8 _note_^{1}.
Commencement of the work, 9.
Construction of the Rotherhithe shaft, 9.
Description of the shield, 12.
Journals of Sir I. Brunel of the progress of the work, 10, 11, 16.
Mr. Brunel appointed resident engineer of, 25 _note_^{1}.
First irruption of the river, 29.
Second irruption, 35.
Works suspended, 37.
Resumed, 38.
The Wapping shaft, 38.
Completed and opened, 39.
Its subsequent history, 39 _note_^{1}
Thompson, Dr. Seth.
Letter on the half-sovereign accident, 511
Timber bridges and viaducts, 179
Timber, experiments on strength of, 182, 227
Torquay branch of the South Devon Railway, 87
Trussed bridges, 199
Uxbridge branch of the Great Western Railway, 86
Vale of Neath Railway, 89.
Viaducts, 171
Vick, Alderman William, his bequest for a bridge at Clifton, 47
‘Victoria’ steam-ship, built under Mr. Brunel’s direction, 290
Vignoles, C., 74
Walker, J., 107
Walkham viaduct, 189
Wapping shaft of the Thames Tunnel, construction of the, 38
Watcombe, Mr. Brunel’s life at, 514
Watt, James & Co., 148.
Tender accepted for screw engines of the ‘Great Eastern,’ 301
West Cornwall Railway, 87.
Viaducts, 189
Westminster Abbey, memorial window in, 520 _note_^{1}
Wilts and Somerset Railway, 88
Windsor branch of the Great Western Railway, 86
Windsor bridge, 200.
Description of superstructure, 200.
Mode of forming piers, 201
Wire gun, 453
Witness, Mr. Brunel’s reputation as a, 69, 93, 505
Wood, Nicholas, 101.
Report on broad gauge and permanent way, 107
Wrought-iron bridges, 192
Wrought-iron girder, experiments on, 193
Wyatt, Sir M. D., 84
Wycombe extension of the Great Western Railway, 86
LONDON: PRINTED BY
SPOTTISWOODE AND CO., NEW-STREET SQUARE
AND PARLIAMENT STREET
* * * * *
Typographical errors corrected by the etext transcriber:
known method of makng=> known method of making {pg 45}
consits merely of=> consists merely of {pg 109}
every calcluation=> every calculation {pg 527}
* * * * *
FOOTNOTES:
[1] To avoid confusion, Sir Isambard Brunel has been called throughout
by that designation, the one by which he is generally known: he was
knighted on March 24, 1841.
His Life has been written by Mr. Richard Beamish, F.R.S. (London, 1862.)
[2] Lady Brunel survived her husband five years. Of their children,
three lived to maturity, one son, Isambard Kingdom, and two daughters,
Sophia, wife of the late Sir Benjamin Hawes, K.C.B., Under Secretary of
State for War, and Emma, wife of the Rev. George Harrison, Rector of
Sutcombe.
[3] He was sent to Paris to recover his knowledge of French, which had
got rather rusty at school, and also to study mathematics. He retained
through life a great admiration of the method of teaching this subject
which was adopted in France.
In addition to the time spent in the study of mathematics and languages,
Mr. Brunel occupied himself on his holidays in examining the various
engineering works going on in Paris, and he used to send his father
drawings and descriptions of them.
[4] Sir Isambard was also consulted upon a proposed suspension bridge
over the Tamar at Saltash, where Mr. Brunel subsequently built the Royal
Albert Bridge.
[5] This history has been written by Mr. Beamish in his _Life of Sir
Isambard Brunel_, pp. 202-304, and also, up to the year 1828, in the
very valuable work by Mr. Henry Law, C.E., entitled ‘A Memoir of the
several Operations, and the Construction, of the Thames Tunnel,’ and
published by the late Mr. Weale in his _Quarterly Papers on
Engineering_.
[6] For an account of these earlier attempts see Law, pp. 3-7.
[7] This expectation does not seem to have been realised, as there was
never any considerable traffic through the Thames Tunnel. Perhaps,
however, it would have been otherwise had the large descents for
carriages and horses been constructed.
[8] The results obtained by these borings were no doubt fallacious, but
not to the extent which has sometimes been imagined. At a meeting of the
Institution of Civil Engineers, in November 1849, Dean Buckland called
attention to ‘the evils arising from the ignorance of the engineers who
reported to Sir Isambard Brunel, previous to the commencement of the
Thames Tunnel, that the whole of the bottom of the river at that spot
was London clay.’ Whereupon Mr. Brunel rose and said, that he ‘agreed
that knowledge of every kind was most desirable, and that it would be
well if engineers were generally much better informed on many subjects
which would be useful, and more particularly on matters connected with
geology; at the same time he could not admit that they were deficient in
that knowledge of the surface of the earth which was necessary for the
purpose of guiding them in their work. It might be true that many
members of the profession were, like himself, not perfectly well
acquainted with the minute geological characteristics of the soils they
had to deal with, but he thought the education and the practical
experience of the profession generally rendered them well acquainted
with those features and characteristics which were necessary for their
guidance in the design or execution of work. He must also say a few
words in defence of those persons (now nearly all dead) who made the
borings in the Thames, and were stated to have made so fallacious a
report previous to the commencement of the Tunnel. Now, although that
statement had by constant repetition become a sort of historical fact,
it was really only one of those popular fallacies which obtained too
ready credence in the world. The position of the Tunnel was not
determined by any report, or by the result of any borings, but with a
view to establishing a communication between particular localities for
encouraging the traffic which was anticipated from the facility of
access to the docks, and for other local reasons, such as the general
direction of the roads and streets on both shores. After the position
was settled, and not until then, borings were made to ascertain what
soils might be expected in that part of the river. It must be remembered
that these borings were made full twenty-five years ago, when boring in
the bed of a river through a depth of water of nearly thirty feet was
not an ordinary occurrence. The tool then generally employed was the
worm, and tubes were not even used in such cases. The borings showed the
existence in that spot of something which, in the ordinary acceptation
of the term, might have been inadvertently called London clay, but he
had no recollection of its geological designation having ever been
thought of. It was reported and shown to be a very fair clay for working
in.... The errors which were made in giving the results of the borings
did not, in fact, arise from ignorance, but from mechanical defects in
the tools, for it was subsequently discovered that the worm frequently
carried a portion of the upper tenacious clay through the softer strata
beneath, and brought it up again. The tenacious clay might have been
called London clay, but no value was attached to that particular
designation; they cared little in engineering for its denomination,
provided it was of a good tenacious quality. This mistake in terms
(supposing it to have occurred) could not have had any influence on
after proceedings; for, before the Tunnel was far advanced, he conducted
with great care a series of borings extending across the Thames, and, as
he used improved tools and worked through tubes, the holes were kept so
dry that a candle was frequently lowered down to the bottom in order to
see the amount of infiltration. By this means he was enabled to
construct a correct section of the bed of the Thames at that spot,
showing every layer of shells and gravel as well as every variation of
the surface of the silt, &c. He entered more at length into these
details than might perhaps appear necessary, because he felt it was
incumbent upon those who had the conduct of works to show that they did
not proceed so ignorantly or so recklessly as had been assumed, in the
design or execution of large undertakings.’
[9] The paragraphs in small type, without any reference, are from Sir
Isambard’s journals. The sentences inserted at the side are his marginal
summary. Occasionally a few words are added (in square brackets) by way
of explanation.
[10] The shaft subsequently made on the Wapping shore was sunk to its
full depth without any under-pinning.
[11] Professor Rankine, in his work on _Civil Engineering_, p. 599,
describes the Thames Tunnel works under the significant heading
‘Tunnelling in Mud.’
[12] _Proceedings Inst. C. E._ i. 34. The circumstances which led Sir
Isambard to conceive the idea of a shield, and the earlier designs he
made for it, are described, with illustrations, by Mr. Law, pp. 7-10.
[13] Mr. Law’s memoir contains a detailed description of every part of
the shield, illustrated by careful drawings.
[14] Mr. Beamish had joined the works on August 7.
[15] On November 20 Mr. Brunel mentions in his diary that he had ‘passed
seven days out of the last ten in the Tunnel. For nine days on an
average 20⅓ hours per day in the Tunnel and 3⅔ to sleep.’
[16] On the previous day Mr. Brunel had been formally appointed resident
engineer.
[17] Mr. Gravatt had been appointed an assistant engineer six months
before.
[18] Sir Isambard’s journal of this eventful night consists--as he was
not himself present--of Mr. Beamish’s journal, with a few words in warm
commendation of that gentleman’s ‘judgment, coolness, and courage,’
followed by observations upon the stability of the shield. He then gives
a statement made by Mr. Gravatt, and taken down in shorthand. No
extracts are given in the text from Mr. Beamish’s narrative, as he has
already inserted it in a condensed form in his _Life of Sir Isambard
Brunel_, pp. 244-248.
[19] Mr. Michael Lane, at this time foreman bricklayer, became one of
Mr. Brunel’s most valued assistants, and was employed by him on the
Monkwearmouth Docks and the Great Western Railway. After filling various
posts in the service of that company, he was in 1860 appointed their
principal engineer, an office which he held till his death, in February,
1868.
[20] On this occasion an amusing incident occurred. Mr. Brunel was
exceedingly unwilling to permit his visitors to make this expedition
into the arch; but on the assurance that they could all swim perfectly
well, he consented to take them, with the understanding that, if he
jumped overboard, they were immediately to follow his example, and swim
after him to the shaft. While they were in the arch Mr. Brunel (as Sir
Isambard mentions) fell overboard. As soon as he recovered himself, and
turned to swim back to the boat, he remembered that he had unwittingly
given to his companions the signal to jump out into the water. He was
much amused, on looking up, to see that they were not swimming after
him, but were still sitting in the boat clinging to the gunwale, with
faces expressive of blank despair.
[21] Mr. Brunel’s comment in his diary is as follows:--‘Without
ascribing any particular merit to myself, I cannot help observing, for
my future guidance, that being alone, and giving few but clear orders,
and those always to the men who were to execute them, I succeeded in an
operation not altogether mean, and which a very trifling want of
precaution or order might have caused to be a total failure.’
[22] On January 15, 1828, the Directors of the Thames Tunnel Company
passed the following resolution, which they ordered to be advertised in
the _Times_, _New Times_, _Herald_, _Ledger_, and _Courier_:--‘That this
court, having heard with great admiration of the intrepid courage and
presence of mind displayed by Mr. Isambard Brunel, the company’s
resident engineer, when the Thames broke into the Tunnel on the morning
of the 12th instant, are desirous to give their public testimony to his
calm and energetic endeavours, and to that generous principle which
induced him to put his own life in more imminent hazard to save the
lives of the men under his immediate care.’
[23] The Thames Tunnel was not successful as a commercial undertaking;
but it has always been considered, especially by foreigners, one of the
most interesting sights in London, and has been visited by several
millions of persons. In 1865 it was purchased by the East London Railway
Company, and trains now (March, 1870) run through it. The possibility of
using the Tunnel as a railway had been considered in Mr. Brunel’s
lifetime, and the idea was approved of by him.
[24] This description is based on the translation given by Mr. Drewry
(_Suspension Bridges_, London, 1832, p. 75), from the _Mémoire sur les
Ponts Suspendus_, by M. Navier (Paris, 1823, p. 49). M. Navier saw the
bridges when they were erected at Sheffield in May 1823.
[25] The dimensions of these designs were as follows:--
(_a._) Length of floor 890 feet.
Distance between points of suspension 980 "
Length of chain 1,300 "
With a capacity to bear excessive load of 650 tons.
(_b._) Length of floor 916 feet.
Distance between points of suspension 1,160 "
Length of chain 1,468 "
With capacity to bear excessive load of 650 tons.
[26] On plate I. is given (fig. 1) a facsimile on a smaller scale of the
drawing sent in by Mr. Brunel for the last-mentioned (_b_) of these two
designs.
[27] See below, p. 60.
[28] See above, p. 42.
[29] The dimensions proposed in this design were as follows:--
Distance between points of suspension 600 feet.
Versed sine 60 "
Width of roadway 32 "
[30] A few days before this ceremony, an iron bar, 1½ inch diameter, and
about 1,000 feet in length, was hung across the valley from Clifton
Rocks to Leigh Down, to facilitate the works. It was traversed by a
basket pulled by ropes. The first few journeys of this machine were
somewhat perilous. It was intended that Mr. and Mrs. Brunel should be
the first passengers; but, when all was ready, one of Mr. Brunel’s
assistants started on a clandestine trial trip, and owing to a bend in
the bar, the basket stuck half way, and the mast of a passing steamer
caught in the rope. The rope was however cut, and he was drawn back.
When the apparatus had been put to rights, on another occasion, when Mr.
Brunel was in the basket, it got jammed, and he had to climb up the
connecting link and get upon the bar, before he could release the
basket.
[31]
Span 702 feet 3 inches.
Versed sine 70 "
Roadway above high-water 248 "
[32] Plate I. fig. 2 (p. 49), shows an elevation of the bridge according
to the designs on which it was commenced.
[33] See Mr. Brunel’s remarks:--_Proceedings Inst. C. E._ for 1841, pp.
78, 79.
[34] Rollers on an arched surface had been used previously in several
bridges.
[35] The chains were used in the construction of the Saltash bridge.
[36] Speech of the Chairman, the late Captain Mark Huish, at the first
general meeting, August 2, 1861.
[37] Some re-arrangement of Mr. Brunel’s design was rendered necessary
in order to adapt the Hungerford bridge chains to the Clifton bridge,
and there are three chains instead of two, as in Mr. Brunel’s design.
The platform is stiffened by wrought-iron girders instead of by timber
trussing, and the whole bridge is stiffened transversely by the
wrought-iron girders at the sides, which are connected throughout by
diagonal bracing. The clear width of the bridge is 30 feet, 5 feet less
than originally intended. It should be added, that no attempt has been
made to complete the towers according to Mr. Brunel’s architectural
designs.
[38] A graphic account of this famous parliamentary contest will be
found in the third volume of Mr. Smiles’ _Lives of the Engineers_,
chapter xi.
[39] See Mr. Smiles’ _Life of George Stephenson_, p. 325.
[40] See Mr. Smiles’ _Lives of the Engineers_, vol. iii. chap. xv.
[41] By means of the railway (it was said) goods would be conveyed with
ease from London to Reading in _three or four hours_, and from Bath to
Bristol in _one hour_.
[42] During Mr. Stephenson’s cross-examination, several questions were
put to him as to the dangerous consequences which might be expected to
result from travelling through a tunnel a thousand yards long. At length
he lost all patience at the ignorance displayed by the questions put to
him by counsel, and the following passage of arms took place:--
‘_Mr. Stephenson._ I wish you had a little engineering knowledge--you
would not talk to me so.
_Counsel._ I feel the disadvantage.
_Mr. Stephenson._ I am sure you must.’
In other parts of the engineering evidence there are some statements
which read strangely enough at the present day, as for example the
following: ‘The noise of two trains passing in a tunnel would shake the
nerves of this assembly. I do not know such a noise. No passenger would
be induced to go twice.’
[43] At this time the Lords’ committees were open to all peers who chose
to sit on them, and it was not considered indecorous for peers who had
not attended any of the previous sittings to vote on the division.
[44] The Great Western Railway was constructed with but few deviations
from the line sanctioned in 1835. The only alteration of any importance
was at the London end, where, by an Act passed in 1836, the line was
taken to Paddington, instead of joining the London and Birmingham
Railway near Kensal Green. This change of plan was rendered necessary by
reason of a difficulty having arisen between the two companies as to the
terms of their agreement, and not, as has been often stated, in
consequence of the adoption of the broad gauge on the Great Western
line.
[45] Sir William Armstrong’s hydraulic machinery at Paddington is
described by him in a communication printed in the _Report of the
British Association_ for 1854, p. 418: ‘I have also applied it [water
pressure machinery] extensively to railway purposes chiefly under the
direction of Mr. Brunel, who has found a multitude of cases involving
lifting or traction power in which it may be made available. Most of
these applications are well exemplified at the new station of the Great
Western Railway Company in London, where the loading and unloading of
trucks, the hoisting into warehouses, the lifting of loaded trucks from
one level to another, the moving of turn-tables, and the hauling of
trucks and traversing machines are all performed, or about to be so, by
means of hydraulic pressure supplied by one central steam engine with
connected accumulators.’
[46] See p. 104.
[47] No copy of this report can be found; but documents of subsequent
date sufficiently indicate the nature of the arguments Mr. Brunel used
in it.
Mr. Brunel had about this time given much attention to the principles of
wheel carriages, as is manifested by an interesting article ‘On Draught’
written by him for the work on ‘The Horse,’ published by the Society for
the Diffusion of Useful Knowledge.
[48] With regard to this point, Mr. Brunel afterwards admitted that he
had held a mistaken opinion. In speaking of his reasons for adopting the
narrow gauge on the Taff Vale Railway in 1838, he said before the Gauge
Commission:--‘One of the reasons, I remember, was one which would not
influence me now; but at that time I certainly assumed that the effect
of curves was such, that the radius of the curve might be measured in
units of the gauge, in which I have since found myself to have been
mistaken.’
[49] See Mr. Brunel’s report of August 1838, printed in Appendix I. p.
528.
This plan was never adopted, as it was found desirable upon the broad
gauge to use still wider carriages overhanging the wheels; but advantage
was taken of the broader base to use wheels of greater diameter.
However, in the saloon carriages, where ease of travelling was the chief
object aimed at, the bodies were placed within the wheels.
[50] In the course of constructing the earth-works of a railway, the
contractors were accustomed to lay down _temporary ways_ or lines of
rail, for the earth waggons to travel upon. When these were done with,
the proper road for the trains was laid down; and this, to distinguish
it from the former one, was called the _permanent way_.
[51] See Wood _On Railways_, 3rd. edit. 1838, p. 151.
[52] A full description of the original road of the Great Western
Railway, communicated by Mr. Brunel, will be found in Wood’s _Treatise
on Railroads_, 3rd edit. 1838, p. 708.
[53] At this time Mr. Brunel was confined to the house by the effects of
his accident on board the ‘Great Western’ steam-ship (see p. 242). Had
he been on the spot, he would have been able to give the work careful
consideration during its progress, and to judge of the expediency of
proceeding with the plan.
[54] The continuity of the timbers diminishes the risk of trains leaving
the line from small imperfections in the permanent way. And, should a
train leave the rails, the injury to the carriages and to the road is
generally less serious than it is when the wheels of a carriage off the
rails come into repeated and violent contact with the cross sleepers.
Instances have frequently occurred where carriages which have left the
rails have run considerable distances on the longitudinal timbers
without injury.
[55] This experiment excited the greatest interest, and it was long
afterwards related how Mr. Brunel, by the stroke of a hammer, had
knocked to pieces the scientific deductions of Dr. Lardner, who, as was
well known, had prompted Mr. Wood’s decision in this matter.
Mr. Brunel was so much impressed with the great influence which the
operation of the blast-pipe had on the working of the locomotive that he
afterwards investigated the whole subject, and made further experiments
to determine whether or not it might be expedient to abandon the steam
blast, and to maintain the draught in the chimney with a fan worked by a
rotary steam jet.
[56] The inconveniences of a break of gauge had already been brought
into notice. One of the narrow-gauge companies, the Midland, worked two
existing lines of railway, one between Birmingham and Gloucester, laid
on the narrow gauge, and another between Bristol and Gloucester, on the
broad gauge; and thus there was a break of gauge at Gloucester.
[57] It should, however, be added, that the Commissioners had stated in
the body of their report: ‘We feel it a duty to observe here, that the
public are mainly indebted for the present rate of speed, and the
increased accommodation of the railway carriages, to the genius of Mr.
Brunel and the liberality of the Great Western Company.’
[58] These experiments will be found in the Appendix to the Report of
the Commissioners of Railways, respecting railway communication between
London and Birmingham (ordered to be printed May 22, 1848).
[59] This was fully borne out afterwards, the express trains running in
the same time, 3 hours, over both routes, though the length of the
broad-gauge line was 129 miles, as against 113 of the narrow. Similar
favourable results have been since exhibited in the competition between
the broad and narrow gauge lines to Exeter.
[60] Among many important advances in railway travelling made on the
Great Western Railway, it may be mentioned that it was on this line that
express trains running long distances without stopping were first
introduced; and that, in 1845, within about a year of the completion of
the line to Exeter, express trains ran from London to Exeter, 194 miles,
in 4½ hours. This rate of travelling, which was accomplished without
difficulty by the broad gauge in its early days, has scarcely been
exceeded since on any railway.
[61] Even in the locomotives when of equal power, Mr. Brunel calculated
that the extra weight was not more than about 500 lbs.
The extra cost of the Great Western Railway was only, including land,
from 300_l._ to 500_l._ per mile, or less than 10 per cent. of the
whole; although Mr. Brunel had taken advantage of the broad gauge to get
carriage bodies 2 feet wider than was then usual.
The wide carriages and waggons were found less costly than the narrow
ones in proportion to the load they carried.
[62] The apparatus patented in 1839 by Mr. Samuel Clegg and Messrs.
Jacob and Joseph Samuda, and improved from time to time by them, was
that adopted in almost all the attempts made in this country to
introduce the Atmospheric System. In reckoning up the force which was
available for mastering the practical difficulties of the undertaking,
the death, in 1844, of Mr. Jacob Samuda must be considered to have been
to his brother, and to all others concerned, a great and irreparable
loss.
[63] A considerable amount of engine power was necessarily consumed in
exhausting the tube before the passage of the train commenced; and it
might at first sight appear that this work was wasted, and that it was
only the work which the engine performed during the passage of the train
which was useful in traction. This, however, was not the case; for, as
was admitted by the more scientific of the opponents of the Atmospheric
System, the power employed in anticipatory pumping was work legitimately
stored up and re-delivered in relief of the engines during the passage
of the train. A waste of power incidental to the Atmospheric System was
indicated by the heat of the air which was delivered by the exhausting
pumps. This waste, however, amounted on the average to only 10 per cent.
of the total work done. A further source of waste of power was the
friction of the air passing along the tube to the exhausting pumps; this
waste was found to amount, on the average, to from 10 to 15 per cent. of
the total work done.
[64] This was almost the only case in which Mr. Stephenson approved of
the application of the System.
Before the Croydon and Epsom Committee, in answer to the question, ‘Does
the Atmospheric railway give you any power of using practically and
usefully steeper inclines than the locomotive railways?’ Mr. Stephenson
said, ‘Yes, I think it does, but still at a very inordinate loss of
power; still it is within the scope of the Atmospheric System under
particular circumstances. I remember a case where it might be
advantageous. Mr. Brunel went to Italy for the purpose of laying out a
line there, and from Genoa over the Apennines he had to form a line; it
would probably rise 15 or 20 miles at 1 in 100 or 1 in 60 or 70. Where
there is that continuous line of ascent, where no stoppages are
required, where the locomotive is totally inapplicable, there I can
conceive nothing more eligible than the Atmospheric plan’ (p. 80).
[65] The length of the line was 52 miles, but as it was considered that
auxiliary stationary power would in any case be necessary on the 10½
miles of very steep inclines, the cost of the Atmospheric apparatus is
taken on 41½ miles.
[66] It must be remembered that beyond the South Devon Railway was the
projected railway through Cornwall, which, with its long and heavy
gradients, was, in all its features, even more suitable than the South
Devon for the application of the Atmospheric System. Had that system
succeeded, and been introduced on the Cornwall Railway, a very great
saving might have been made in the cost of the works of this line.
[67] _I.e._ before the Croydon and Epsom Committee. See above, p. 138.
[68] It will be found on pp. 35-52 of the Minutes of Evidence taken
before the Atmospheric Committee (ordered to be printed April 24, 1845).
[69] This appeared with sufficient clearness from the general comparison
between vacuum, weight of train, and speed. The exact appropriation of
the force employed was shown by some dynamometric experiments made on
the line.
The highest speed recorded was 68 miles per hour, with a train of 28
tons, the speed averaging 64 miles per hour for four level miles of the
line, the vacuum being 16 inches. This speed should have exhibited a
resistance of about 21 lbs. per ton, or 588 lbs., as the running
resistance or friction, and 645 lbs. for the resistance of the air; in
all 1,233 lbs. Now, the pressure due to 16 inches of vacuum on the
piston is 1,390 lbs., which gives 157 lbs. as the friction of the
piston; a result which corresponds sufficiently well with a direct
dynamometric experiment.
Going to the other extreme, there are numerous records of trains of 100
tons which attained, on a level of four miles in length, average speeds
of from 30 to 35 miles per hour, with 16·5 inches of vacuum, one train
of 103 tons going 32·4 miles per hour with 16·9 inches of vacuum.
[70] This valve consisted of a number of long delicate blades of spring
steel, arranged parallel to each other, as in a musical box, but with
wider intervals. These plates rested on a series of truly faced bars,
which crossed the end of the air-passage. The slightest pressure
outwards lifted the springs; and as the area of opening was large, a
very free passage was given to the air. On the current ceasing, the
blades instantly, yet without shock, replaced themselves in contact with
the bars, clipping them tightly under a very small reverse pressure, and
effectually closing the passage. Their merit consisted in their being
almost without weight, and thus promptly re-closing the aperture by a
delicate elastic reaction.
[71] Trains frequently arrived late on the Atmospheric portion of the
South Devon Railway, owing to its being at the end of the long trunk
line from London to Exeter, and having at its other end a locomotive
line contending with very heavy gradients.
[72] It may be mentioned that, from the date of the abandonment of the
Atmospheric System, he refused to receive any remuneration for his
professional services as engineer beyond a nominal retaining fee.
[73] See above, p. 138.
[74] These quantities are the result of the experiments made in
September 1847. They agree with what is now the received opinion of
authorities on train resistances, and represent favourably the case for
the locomotives at the time of Mr. Brunel’s report in August 1844. At
the time when Mr. Brunel wrote his report of August 1844, the weight of
a locomotive, as has been said, bore a higher ratio to its power.
[75] It must be borne in mind that all the inconveniences attending the
use of auxiliary locomotives must be encountered, or else the excessive
dead weight of an engine powerful enough to take a train up the steepest
gradient in a hilly district must accompany it for the whole length of
that part of the line.
[76] No dynamometer was used in these experiments, but all other
requisite data were recorded with the greatest exactness, and the
horse-power employed may be deduced by means of the scale of resistance
which the subsequent dynamomotric trials supply. Moreover, the result
above arrived at for the consumption of coke is verified by an
examination of published indicator diagrams taken off the same engine on
another occasion.
[77] It would of course be impossible here to give a description of all
Mr. Brunel’s bridges, or even to refer to the most important of them
with that minuteness which would be required if this were a book written
for professional use. The following publications may be
consulted:--Bourne’s _History and Description of the Great Western
Railway_, 1846; Brees’ _Railway Practice_, 1837; Simms’ _Public Works of
Great Britain_, 1838; _Proceedings of Institution of Civil Engineers_,
vols. 14, 25, and generally; Molinos et Pronnier, _Construction des
Ponts Métalliques_, 1857; Humber’s _Cast and Wrought-Iron Bridge
Construction_, 1861; and Humber’s _Record of Engineering_ for 1866. At
the end of the description of many of the bridges in this chapter a note
has been given of publications in which the bridge has been referred to.
[78] In the early days of the Great Western Railway special designs were
made for every one of the ordinary bridges over and under the railway;
but when, in consequence of the rapid extension of the Great Western
system, the number of bridges to be designed became very large, Mr.
Brunel had a set of ‘standard drawings’ prepared and engraved, which
embodied the experience gained, and contained designs suitable for
various situations. The contract drawings were made by adapting to the
particular circumstances of each case the standard drawing which was
most applicable to it. This system, besides securing uniformity of
construction, introduced a considerable amount of economy; since, the
standard drawings being based upon the results arrived at in an
extensive practice, the proper structural arrangements and dimensions
were indicated with far greater accuracy than could be attained in a
reasonable time by an independent calculation in each individual case.
[79] It was called the ‘Wharncliffe Viaduct,’ in acknowledgment of the
services rendered to the Company by the late Lord Wharncliffe as
Chairman of the Committee in the House of Lords. Drawings of this bridge
are given in Simms’ _Public Works of Great Britain_, 1838, pl. 54, 55,
and 56; and in Bourne’s _History and Description of the Great Western
Railway_, 1846.
[80] At the back of retaining walls, such as the abutments and wing
walls of bridges which were subject to the pressure of earth behind
them, Mr. Brunel introduced what were termed ‘sailing courses,’
projecting shelves corbelled out at the back of the wall. The weight of
earth resting on these shelves virtually increased the weight of the
back of the wall, and assisted it in resisting the forward pressure of
the earth.
[81] During the construction of the bridge a part of the crown of the
eastern arch proved defective, in consequence of the cement in the
middle of the brickwork not having set sufficiently at the time when the
centering was eased. Apprehensions which had been entertained by some as
to the safety of the structure were groundless, for when the defective
part was taken out and replaced, no further trouble was experienced. The
bridge has stood well, and has shown none of those symptoms which an
overstrained structure exhibits.
[82] Simms’ _Public Works of Great Britain_, pl. 57, 58; Bourne’s
_History and Description of the Great Western Railway_, p. 36.
[83] When Mr. Brunel for architectural effect employed Gothic or pointed
arches, he occasionally made the main part of the arch of a form
different from the curve visible on the face, but he more frequently
made it of the same pointed form throughout. In this case he did not
obtain equilibrium by loading the crown, but he kept the line of
pressure sufficiently within the thickness of the arch by strengthening
the haunches.
[84] Brees’ _Railway Practice_, pl. 42.
[85] There is an illustration of this bridge in Bourne’s _History and
Description of the Great Western Railway_.
[86] Joggles are small pieces of hard wood or cast-iron of rectangular
cross section, placed between two beams, and fitted carefully into
notches cut across them. The beams are then bolted firmly together. The
object is to stop the slipping which would occur between the two
surfaces if the beams were merely laid one on the other and loaded, and
so to make two pieces of equal size act as one of double the depth, and
therefore of four times the strength of a single piece. In 1841 Mr.
Brunel made experiments to satisfy himself of the strength gained by
this method; and he afterwards perfected the arrangement by ensuring an
exact fit in the notches by tightening up the joggles with wrought-iron
wedges.
[87] A drawing of this bridge is appended to the _Report of the
Commission on the Application of Iron to Railway Structures, 1849_.
[88] Mr. Brunel, by taking care in his timber structures to distribute
the load uniformly, was frequently able to dispense with costly
foundations. On one occasion a timber viaduct 30 feet high was placed
upon a broad platform resting on an old embankment upwards of 50 feet in
height. A similar arrangement was adopted by him in some cases on slips
in embankments which it would have been uncertain and expensive to make
up with earthwork.
[89] For a description of this viaduct, see _Proceedings Inst. C. E._,
vol. xiv. for 1854-5, p. 492.
[90] Mr. Brunel about this time introduced a great improvement in the
manufacture of wrought-iron bolts for bridges, when these, as is usually
the case are screwed at the ends. A screw cannot be made on a bolt
without the metal being cut into to the extent of the depth of the
thread, and the strength thereby considerably reduced. The section,
taken at the bottom of the thread, is much smaller than that of the
bolt; and, moreover, owing to the abrupt change at the commencement of
the thread, the strength is not so great as that due to the reduced
sectional area. The improvement consisted in swelling out the iron of
the end of the bolt where the thread was to be made, so that the
diameter, at the deepest part of the thread, should be fully equal to
that of the bolt. The saving of metal by this improvement, especially in
the case of long bolts, is very considerable.
[91] An arrangement was introduced by Mr. Brunel to prevent any
disturbance in the permanent way by a settlement of the embankments at
the ends of the viaducts. There were no large abutments and wing walls,
but the end of the viaduct was formed with a queen truss in the parapet,
which rested on a platform on the top of the embankment slope. In any
slight settlement of the earth, the end of the viaduct sunk with it, and
the permanent way was not disturbed. Wedges were provided to raise the
ends of the trusses and readjust their level. This was an important
provision, as it applied to about 60 cases on the Cornwall Railway.
[92] The simple arrangement of the timber-work was specially arranged
with a view to giving facility for replacing portions of it, should they
decay.
[93] The viaducts on the Cornwall Railway between Plymouth and Truro are
thirty-four in number. Of these there are nineteen which have from six
to twenty openings, and are from 80 to 153 feet in height. The aggregate
length of these nineteen viaducts is nearly 2¾ miles.
[94] A drawing showing this form of section is appended to the _Report
of the Commission on the Application of Iron to Railway Structures_,
1849.
[95] The remainder of this letter is printed in Chapter XVI. p. 486.
[96] Mr. Brunel was thoroughly conversant with the principles of
mathematical analysis, and was able with great readiness to apply it in
practice; but at the same time he preferred, when it was possible, to
use geometrical methods of solution for engineering problems.
[97] In the note at the end of this chapter mention is made of some
experiments made by Mr. Brunel on riveted joints.
[98] See above, p. 185.
[99] A description of this bridge is given in Humber’s _Bridge
Construction_, vol. i. p. 228, and vol. ii. pl. 70, 71, 72; Molinos et
Pronnier, _Construction des Ponts Métalliques_, p. 328, pl. 20, 21, 22.
[100] See _Proceedings Inst. C.E._, for 1847-8, vol. vii. p. 138.
[101] After some perseverance, Mr. Brunel succeeded in getting these
unusually large links, which were 20 feet long, rolled in a single piece
without welding on the eyes. He had to go down himself to the
manufactory in order to get the men into the way of doing the work.
[102] See note at the end of this chapter for experiments on ropes and
chains. The crabs were designed and made specially for this duty. Each
had two barrels, grooved to receive the chain, which was passed several
times round both barrels, so as to get sufficient grip; and it was in
this way possible to wind in with the crabs any length of chain without
having to stop to fleet, as would have been the case had a
single-barrelled crab been used.
These crabs were subsequently used at the floating of the Saltash
trusses, and at the launch of the ‘Great Eastern.’
A similar arrangement was applied in the paying-out machinery of the
Atlantic cable, and is still used for the picking-up gear in the ‘Great
Eastern.’
[103] See _Encyclopædia Britannica_, ‘Iron Bridges,’ vol. xii. p. 601;
Molinos et Pronnier, _Construction des Ponts Métalliques_, p. 320, pl.
23, 24, 25.
[104] These would have been magnificent specimens of timber-work, and a
design for somewhat similar trusses had at one time been prepared for
the Chepstow Bridge. It is worthy of mention that Sir Isambard Brunel at
one time designed a timber arched bridge of 800 feet span to cross the
Neva at St. Petersburg.
[105] Before the work was begun Mr. Brunel made calculations to
determine whether or not it might be desirable to cross the river with
one span of 850 feet, in order to avoid the great depth at the centre
pier.
A few extracts from letters relating to bridges of large span will be
interesting:
‘January 31, 1852.
‘I have revised my calculation as to a span of 1,000 feet, and find
that even with the loads and limitations of strains which I
adopt--namely a proper thickness of ballast, and a possible load of
a train of engines without tenders, and a limitation under such a
load of 5 tons’ strain per square inch, that a span of 1,000 feet
may be made in England of the very best workmanship, and sent out
and erected for I should say safely 250,000_l_., of course a single
way--another 250,000_l_. ought, I should think, to cover the rest
of the bridge.
I should like to explain to you the mode I should propose for
raising such a bridge, weighing 7,000 tons.
‘December 1, 1852.
As you ask me my opinion of the advisability of patenting your
bridge, I give it you; though you will probably be the first person
who will have followed such advice if you do so, and might safely
patent such a novel mode of using advice.
In my opinion you cannot patent the bridge. Without detracting in
the least from your merit of invention, the form has been so
frequently and exactly applied that no patent could hold. The
Saltash bridge now just advertised for letting is exactly on the
same principle as regards form; and this is so old to my knowledge
that I can claim no invention, and the use of cast iron for such
purpose is also incapable of being patented. There is much that is
good in your bridge, and you deserve credit, but you would find
innumerable claimants to dispute, and successfully, your attempt to
claim a monopoly by a patent--I myself for one. Besides, I see it
published in a book.
‘May 30, 1854.
‘As to your present enquiry, I do not think that what I am doing at
Saltash would be applicable in this case; but without being guilty
of great presumption, I think I may say that if the same plan will
not do, it is fair to assume that the same brains which concocted
the plan to suit the difficulties of the Tamar might very likely
find the means of overcoming those of the Severn.
If I should be able to suggest a feasible plan, and there should be
found people ready to make it, I shall have the satisfaction of
bridging the Severn as well as the Tamar.’
[106] It has of course been impossible to refer to the points on which
Mr. Brunel was aided, in his different works, by the suggestions of his
assistants; but it may be mentioned here that, as appears from one of
Mr. Brunel’s letters, the plan of working under a diving-bell had been
proposed by Mr. William Glennie, his assistant, before he knew that Mr.
Brunel had decided to adopt it.
Mr. Brunel also mentions in another letter that the ‘very simple and
effectual manner’ of applying the pneumatic apparatus, by forming the
annular space round the circumference of the bottom of the cylinder, was
suggested to him by Mr. Brereton, when the method of constructing the
cylinder was being finally settled.
[107] In the _Proceedings of the Institution of Civil Engineers_, vol.
xxi. 1861-2, will be found a paper by Mr. Brereton, giving a detailed
description of the means employed for the construction of the central
pier.
[108] Shortly after Mr. Brunel’s death some of his friends on the Board
of the Cornwall Railway placed the following inscription, in raised
letters, over the lard archways--I. K. BRUNEL, ENGINEER, 1859.
[109] A portion of the chains used were those which had been made for
the Clifton Suspension Bridge, Mr. Brunel’s earliest design.
[110] Though it is convenient to explain the nature of the strains in
the Saltash bridge as an arch and suspension bridge combined, it is not
intended to imply that there is any virtual difference between this
truss and the one at Chepstow, for in both the strain on the tube
counteracts the strain on the chains, though the one tube is curved and
the other straight.
[111] Humber’s _Bridge Construction_, vol. i. p. 231; vol. ii. pl. 78,
79, 80.
[112] This load amounted to two and three quarter tons per foot run, in
addition to the weight of the truss. Under this load the central
deflection was about 5 inches.
The strain on the iron of the tube and of the chains with a load of one
ton per foot run, in addition to the weight of the truss, flooring, and
ballast, is under four tons per square inch.
[113] The difficult operations of floating and lifting the
superstructures of the Chepstow and Saltash bridges were carried out
entirely by Mr. Brunel and his assistants, there being no contractor
engaged in, or responsible for, the work in either case.
[114] A photograph taken shortly after the floating of the second tube
forms the frontispiece of the first volume of Humber’s _Bridge
Construction_.
[115] See above pp. 190 and 193.
[116] It has been observed with much truth that full justice has not
been done to Mr. Brunel’s exertions in this department of practical
science.--See ‘Address of George Parker Bidder, Esq., on his election as
President of the Institution of Civil Engineers, January 10, 1860.’
[117] Captain Claxton died on March 27, 1868, in his 79th year. The
manuscript of this and the three following chapters was fortunately
completed in time to be submitted to him. He spared no trouble either in
giving or procuring original documents and other materials for all parts
of this book, in the preparation of which he took the liveliest
interest.
[118] To enable the ship to resist the action of the heavy Atlantic
waves, especial pains were taken to give her great longitudinal
strength. The ribs were of oak, of scantling equal to that of
line-of-battle ships. They were placed close together, and caulked
within and without before the planking was put on. They were dowelled
and bolted in pairs; and there were also four rows of 1½-inch iron
bolts, 24 feet long, and scarfing about 4 feet, which ran longitudinally
through the whole length of the bottom frames of the ship. She was
closely trussed with iron and wooden diagonals and shelf pieces, which,
with the whole of her upper works, were fastened with bolts and nuts to
a much greater extent than had hitherto been the practice.
The principal dimensions of the hull and engines are given in the note
to this chapter (p. 245).
[119] The engines as designed by Messrs. Maudslay were beam engines,
although Mr. Brunel had strongly urged them to adopt the more compact
form of direct-acting engines. They, however, thought it better not to
depart from what was then the usual form.
[120] _Steam and its Uses_, by Dr. Lardner, 1856. Chapter on ‘Steam
Navigation,’ section 10.
[121] ‘An exposition of the advantages of the proposed Railway from
Limerick to Waterford.’
[122] _The Steam Engine: its Application to Navigation and Railways,
with Plain Maxims for Railway Speculators_, 5th edition, 1836, p. 307.
[123] It is right to add that, according to the report given in the
_Athenæum_ newspaper of the meetings of the British Association at
Liverpool in September 1837, ‘Dr. Lardner addressed the section
(Mechanical) on his old subject, the application of steam to long
voyages. His remarks and calculations were to a great extent identical
with those brought forward by him last year at Bristol, and published
long since in his work on the steam-engine, but the conclusions were
somewhat varied. The Doctor did not now deny that the voyage might be
practicable, but he did not believe that it would be profitable’
(_Athenæum_, September 23, 1837). Dr. Lardner was answered by several
speakers, and among them by Mr. Guppy, who pointed out in much detail
the unreliable character of Dr. Lardner’s data; while nothing was
suggested about commercial profits or subsidies. It may therefore be
inferred that Dr. Lardner’s arguments as to the consumption of fuel
remained the same, although he may have abandoned the conclusion which
legitimately followed from them--namely, that the long voyages were
practically impossible.
The Report in the _Bristol Mirror_ newspaper of the same date (copied
from the _Liverpool Standard_) is as follows:--‘Dr. Lardner’s speech was
little beyond a repetition of his discourse last year in Bristol,
re-published by him in the _Edinburgh Review_. The voyage to America by
steam he treated as practicable, but so uncertain as to render a
profitable result hopeless.... During nearly all the year there was an
adverse west wind, and the Gulf Stream was to be avoided.’
[124] She had only _seven_ passengers on board; fifty, it is stated,
were deterred from going in her by hearing of the fire.
[125] These engines were to have had two cylinders of 88 inches
diameter.
[126] It is interesting, in connection with this subject, to mention the
following circumstance. At Mr. Brunel’s recommendation, Mr. Humphrys
consulted Mr. James Nasmyth as to the best means of forging the large
paddle-shaft; as they could not get any manufacturer to undertake it. To
accomplish this forging Mr. Nasmyth designed his steam-hammer, and
though it was not then erected in Bristol, in consequence of the
alteration of the form of the engines of the ‘Great Britain,’ it soon
afterwards came into general use.
[127] In the Minute Book of this date it is mentioned as a reason for
postponing any decision on the subject, that Mr. Brunel was making
‘final,’ and afterwards ‘further,’ experiments.
[128] See Mr. Guppy’s paper, printed in the _Proceedings of the
Institution of Civil Engineers for_ 1845, p. 151.
[129] This report is printed in Appendix II. p. 539. The paragraphs in
which Mr. Brunel describes the advantages of the screw propeller will be
found at page 552.
[130] A description of Mr. Humphrys’ trunk engines is given in
Tredgold’s work on the steam engine (ed. 1838), p. 390.
[131] The balanced rudder, which is peculiarly applicable to screw
ships, has encountered much opposition; but it has lately been
successfully introduced by Mr. E. J. Reed, C.B., into vessels designed
by him for the Royal Navy.
[132] It maybe convenient here to state that the dock in which the
‘Great Britain’ was built led into the Floating Harbour, which is a
portion of the channel of the river Avon closed in. The Floating Harbour
communicates through the Cumberland Basin with the river.
[133] One of the consequences of the publication of this report was,
that Mr. Brunel received so many letters containing suggestions for
lifting and floating the ship, that he was obliged to have a circular
letter printed declining assistance; and more than four hundred letters
were also received by the Company’s secretary.
[134] ‘The “Great Britain” Steam-Ship. Extracts from the letters of
Captain Claxton, R.N., to I. K. Brunel, Esq., and the Directors.
Bristol, 1847.’
Mr. Bremner’s apparatus is also described in a paper read by him at the
Institution of Civil Engineers, and printed in the twenty-first volume
of the _Transactions_, p. 160.
Accurate illustrations of the break-water and floating apparatus will be
found in the _Illustrated London News_ of August 21, 1847.
In publishing the correspondence to which reference has been made, the
Directors acknowledge their obligations to all concerned in the arduous
task of saving the ‘Great Britain;’ and they add--‘to Mr. Brunel above
all their thanks are most due, for opening their eyes to what might be
accomplished, and for taking upon himself the responsibility of her
release, provided that Captain Claxton was employed to carry out his
views.’
[135] Sir E. Parry was at that time Controller of Steam Machinery, and a
warm supporter of those who desired to make a fair trial of the screw
propeller.
[136] Bourne, on the _Screw Propeller_, ed. 1867, p. 263.
[137] The records of these trials, found among Mr. Brunel’s papers, show
results which coincide in all material points with those given by Mr.
Bourne at p. 284 of his work on the _Screw Propeller_, ed. 1867.
[138] Bourne, Appendix, p. xxxiii.
[139] The letter to Mr. Guppy of August 1843 (given above, p. 259)
contains a reference to some of Mr. Brunel’s ideas upon iron
shipbuilding, subsequent to the date of the design of the ‘Great
Britain.’
[140] Extract from a memorandum by Mr. Brunel (dated February 25, 1854)
on the early history of the great ship.
[141] So Mr. Brunel wrote to the secretary when excusing his own absence
from the meeting on account of illness.
[142] Mr. Brunel concludes this report by indicating the best mode of
contracting for the construction of the ship and engines, and suggests
that an examination should be made of the river Hooghly.
[143] From the great length of this report it has been necessary to omit
the less important paragraphs.
[144] The passages which are omitted refer to the relative cost and
merits of the different tenders.
[145] Two years later Mr. Brunel spoke of the success of the screw
engines as ‘a most grave question upon which hangs I fear to think how
much.’
[146] Mr. Geach was one of the most zealous friends of the great ship.
His death, within a year after the commencement of the work, was the
first of her many misfortunes.
[147] Stringent conditions as to jacketing were introduced into the
contracts; but they were not enforced by Mr. Brunel, in deference to the
strong objections urged by the makers. He much regretted this
concession.
[148] The destination of the ship as proposed at this time was
Australia.
[149] The power of blowing off the steam without noise is of great
importance, and Mr. Brunel made many experiments on the point. The noise
of the steam blowing off, when the engines of a ship are stopped for
fear of an impending collision or other accident, is so great, that it
is almost impossible to hear any orders that may be given.
[150] The screw propeller of ‘Agamemnon’ was broken in a trial trip
outside Plymouth Sound, on November 9, 1853; and the result was that,
from not having efficient governors, the engines flew round at an
alarming speed.
[151] Mr. Russell’s works. The ship was built in a yard immediately
adjoining them.
[152] See, for example, an article in the _Quarterly Review_ of March
1856, entitled ‘The Triton and the Minnows.’
[153] It must be remembered that this report describes the ship as she
was at that time designed by Mr. Brunel.
[154] Extract from memoranda of October 5, 1855:--
‘By constant observation, to lay down position and course of ship, and
correct compasses.
‘To record speed of ship through water by logs.
‘Revolution of engines.
‘Force and direction of wind.
‘Draught and trim of ship, sails carried, &c.
‘Temperature and peculiarities of sea water.
‘As the result of these observations, to plot down hour by hour the
position of the ship, to compute the speed, variations of compass, the
direction and force of current, and true direction and force of the
wind.’
[155] Mr. Brunel also proposed to have charts prepared for the route of
the great ship to Australia and Calcutta, similar in character to some
which were made under his directions for the route of the ‘Great
Western’ to New York, which he described as follows:--
‘When we started the “Great Western” to New York, I had a chart drawn
and engraved of the sea (that is, the lines of latitude and longitude,
and the bearings of the compass, and the coast and soundings) on a
cylindrical projection of a great circle from Bristol to New York; and
we found it very useful for the captain to _see_ his great circle
sailing, and to see how much he was deviating from it.’
[156] Captain Harrison’s command of the ‘Great Eastern’ after she left
the river was unhappily of but short duration, as he was drowned by the
accidental upsetting of his boat in Southampton Water on January 21,
1860, four months after Mr. Brunel’s death.
[157] With this paper Mr. Brunel enclosed a letter, in which he points
out with great earnestness the responsibility of his own position.
After calling the Directors’ attention to the important step they were
about to take, he proceeds:--
‘I am not pointing out a danger without being prepared to propose a
remedy. The same man who, after he has been selected and appointed on
account of his previous character as a sailor, and as an experienced
naval man, would probably feel disposed to reject advice coming from
those who do not profess to be sailors, and to resist directions which
might appear to him as trenching upon his authority, or as implying
doubts of his ability, could have no such feeling (if he is a sensible
man and fit for the position) if his attention had been drawn to these
views before his appointment, and if he accepts the trust reposed in him
on the understanding that he is expected to pay attention to these
opinions, and if, as I shall urge upon the Directors to ascertain, he
entertains no objection to the adoption of them, and agrees to follow
the principles of action which I hope to induce the Directors to adopt
as rules in the navigation of the ship.
‘I propose therefore to lay before the Directors the result of my
anxious consideration of this subject, to urge upon them the adoption of
my views, and, if they adopt them, to urge that they should make it a
condition in the selection and appointment of a commander that such
views are approved of and adopted by him.
‘This is a strong and plainly stated request, but not more strongly put
than I feel that the occasion requires.
‘I have an immense stake in the success of this enterprise. I do not
refer merely to my pecuniary investment; but, as affecting my
professional reputation, my stake is much deeper; as, although I was
accidentally led by circumstances into proposing the plan we have
adopted, and the Company was not originally formed to carry it out, and
although the plan when proposed was well weighed and considered by men
competent to judge, at all events, upon the prospects as a commercial
speculation, and although it was adopted by them, and therefore they
must share in the responsibility, and although many may share with me in
the credit of our success; yet there is no doubt that I should have to
bear solely and very heavily the blame of a failure. On this ground
alone, therefore, the Directors, I am sure, will willingly allow me to
urge my views strongly, and will excuse the length at which I do so. But
I shall rely upon satisfying them that my views and opinion should
command their concurrence on their own merits; and with this preface,
which has already reached an undue length, I will lay before them a
paper on the subject, most of which has been written for some time in
anticipation of the present circumstances, and having been thus written
at different periods is, I fear, somewhat disjointed, and wanting in
arrangement, and therefore much longer than it might have been.’
[158] Shortly after the publication of this report, Mr. Brunel received
a letter from Mr. G. W. Bull, of Buffalo, U.S.A., encouraging him to
adopt the plan of launching sideways, as that was the way in which the
large steamboats of the American lakes were launched. In the course of a
correspondence which ensued, Mr. Bull gave much information as to the
manner in which these launches were effected. He advocated a free launch
for the ‘Great Eastern.’
[159] For an account of this and other experiments and observations on
friction, see note A at the end of this chapter.
[160] The power mentioned here as applied for starting the ship was two
hydraulic presses, to overcome adhesion at the first start. The river
tackle was relied on to overcome the friction.
[161] See below, note A, p. 389.
[162] The reason for stopping was lest the ship should float at high
water during the night.
[163] It remained a doubtful point whether or not the bow cradle was
stopped by the brakes. Subsequent experience favoured the opinion that
it had stopped of itself.
[164] The ship had always been spoken of as the ‘Great Eastern,’ and
this name was specially agreeable to Mr. Brunel. It was not a point on
which he set much store, but his views were pretty well known; and, as
the name had not been of his choosing, but had rather grown out of the
name of the Company, and the natural association of ideas with his first
ship, the ‘Great Western,’ it might reasonably have been supposed that
it would have been adopted. But some fastidious person suggested that
the name was objectionable, as consisting of two adjectives. A list of
names was prepared and submitted to Mr. Brunel on the day of the launch
at the moment when he was busiest. He said off-hand that they might call
it ‘Tom Thumb’ if they liked. The Directors, however, selected the name
‘Leviathan,’ and so the ship was christened. The new name never stuck to
the ship, and she was registered as the ‘Great Eastern.’
[165] The action of an hydraulic press is limited to the length of
stroke of the ram. Hence, as soon as the ship moved a distance equal to
the length of the stroke, it became necessary to relieve the water
pressure in the cylinder, to pull back the ram into it, and to insert
between the ram of the press and the cradle an additional length of
timber. This operation of pulling back the ram and putting in another
length of timber was called ‘fleeting’ the press, a term used in many
mechanical operations when the motive arrangements are reinstated in
their primary position ready for a further advance in the work.
[166] On this occasion Mr. Brunel had his way, and there were not a
dozen spectators in the yard.
[167] See note A at the end of the chapter.
[168] At this time the friction when the ship was in motion was not much
greater than it had been on previous occasions; but, the adhesion being
greatly increased, a large excess of power became stored up in the
elasticity of the abutments and the chains. This excess of power, on the
ship commencing to move, discharged itself in giving her velocity, and
therefore she moved by short slips, instead of by a gradual motion, as
had been the case previously, when the resistance due to friction and
that due to adhesion had been more nearly equal. For observations on the
friction, see note A at the end of the chapter.
[169] Mr. Stephenson went with Mr. Brunel into all the facts relative to
the operations and all the experience gained therefrom, and examined
carefully the investigations which had been made by means of
self-recording apparatus, and which showed that the friction diminished
as the velocity increased. So struck was Mr. Stephenson at these results
that he urged Mr. Brunel on no account to neglect having the brakes
properly attended to; lest the great adhesion should cause a large
amount of stored-up power, which might give the ship such a velocity
that the force of gravity might exceed that of the friction. The brakes
had not been hitherto neglected; but, in conformity with Mr.
Stephenson’s suggestion, it was thenceforward made a rule that, when a
moderate amount of slack had been overhauled from the drums, the brakes
should be put down, on a signal being given that the pressure in the
presses was rising.
[170] Mr. Brunel received a great many suggestions for launching the
ship. Puncheons, gas, artillery, and especially levers, were among the
appliances recommended. With the desire of behaving civilly to
well-meaning persons who were wishing to do him a service, Mr. Brunel
adopted a plan similar to that which he had found useful when the ‘Great
Britain’ was on shore. He had a circular letter printed, thanking his
correspondents for their suggestions, but saying that the number of such
communications had become so great that it was impossible for him to do
more than cause the receipt to be acknowledged, with thanks for the
intentions of the parties writing.
This plan had, however, the effect of increasing the number of his
correspondents, as several of them wrote a second time to express their
regret that their letters had had no better effect than to be classed
with the numerous communications which Mr. Brunel said he had received
on the same subject, which had seemed unworthy of his notice; and they
explained that though other people’s schemes were, no doubt, worthless,
still that their own, if adopted, would launch the ship.
[171] The number of the presses being almost doubled, but the resistance
of the ship not being much greater than before, the elastic compression
of the abutments was less than it had been previously, so that when the
ship moved there was much less work stored up to give it velocity;
therefore the slides were shorter than they had been before.
[172] Among the many congratulations which Mr. Brunel received on the
completion of the launch, there was perhaps none which pleased him more
than the following letter from Mr. Robert Stephenson, who had been
prevented by illness from being present at the concluding operations,
the critical character of which he had fully appreciated:--
February 1, 1858.
MY DEAR BRUNEL,--I slept last night like a top, after I received
your message. I got desperately anxious all day, but my doctor
would not permit me to venture so far away as Millwall.
I do, my good friend, most sincerely congratulate you on the
arrival of the conclusion of your anxiety.
Yours sincerely,
ROBERT STEPHENSON.
A letter from Mr. Brunel to his friend Mr. Froude, describing the
floating, is given in note B to this chapter.
[173] The principal dimensions of the ship and engines are given in the
note to this chapter, p. 416.
[174] During the last-mentioned voyage, returning from Quebec, a
north-easterly wind blew with a velocity of from 30 to 40 miles an hour.
For the first 24 hours the ship paid no attention to the sea; the next
day, the wind remaining the same, but the sea having got more swell on,
the ship began to roll slowly and sedately, the rolls gradually
increasing up to about 9 degrees on either side of the perpendicular,
and dying out again, and then recommencing.
[175] Between the screw and the rudder was what was termed the after
stern-post, which had no duty to perform except to steady the heel of
the ship, into which the rudder was stepped.
[176] Before the ship was finished, Mr. Brunel had her stability and
rolling carefully investigated. Calculations were made to ascertain the
position of her centre of gravity and the other necessary elements for
determining her stability and period of rolling.
He also had a model made, with arrangements for altering the levels of
weights placed inside. By this means the results of the calculations
were verified. It was determined that the ship would make a single roll
from one side to the other in about six seconds. While she was in the
Thames a steamer struck the hulk alongside and gave the great ship a
slight impulse. Mr. Brunel, who was on board, took advantage of the
opportunity to observe the period of the roll she made, and was pleased
at finding it agree with the calculated period. It is to the
investigations initiated at that time by Mr. Brunel that are due the
great steps since made in the knowledge of the laws which govern the
rolling of ships. Had Mr. Brunel lived he would no doubt have taken the
same pains to record the rolling of the ‘Great Eastern’ as he had in the
case of the ‘Great Western’ when, in 1839, he sent an assistant to
America and back, who took observations of the rolling and pitching of
that vessel in several voyages. These observations were made by a simple
angle-measuring instrument, adjusted by the visible level line of the
horizon, and not by the fallacious method of noting down the swings of a
pendulum.
The ‘Great Eastern’ remains almost perfectly steady in ordinary rough
seas. When the seas become very long, so that their period is nearly the
same as that of the ship, she rolls; though the number of degrees on
either side of the perpendicular is not large. By stowing the weights of
cargo high in the ship, the tendency to roll has been much diminished,
and when engaged in cable laying, with the enormous weights in the cable
tanks all placed above the lower deck, she is remarkably steady.
[177] _History of the Atlantic Telegraph:_ New York, 1866.
[178] It may be desirable to give a short explanation of these works,
which consisted principally of a sluice, a trunk, and a drag-boat.
The Sluice was made in the abutment of Prince’s Street Bridge, and was
intended to create a scour after the water had been let off from either
side of the float, the opening at the bridge being closed by a caisson
which had long been in use when (as was formerly the case) the upper
part of the float was scoured through Bathurst Basin.
The Trunk, near the entrance from Cumberland Basin, is a wooden culvert
between the floating harbour and the river. As much of the mud as could
be dragged there was deposited at the entrance of the trunk, and, when
the tide was low in the new channel of the Avon, sluices were opened,
and the water rushed through from the floating harbour, carrying the mud
with it.
The Drag-Boat was fitted with a steam-engine which worked a large
windlass with three compartments, round two of which chains were passed
and fixed to posts on the quays, and the boat was dragged backwards and
forwards. The third compartment of the windlass worked a chain which
elevated or depressed a scraper, attached to a long pole at the stern,
and secured from swerving by a chain-bridle which passed under the boat.
The scraper stirred up the mud, and deposited the more solid parts at
the entrance of the trunk.
Mr. Brunel also desired that the float boards of the Neetham Dam should
be put into proper working order; and that they should be altered so
that, in times of land floods, the whole or a considerable portion of
the excess of water should be retained, and passed through the feeder;
and that even the water of spring tides should be allowed to pass the
dam, and then be stopped back for the same purpose.
[179] The advantage of forming an air-chamber in the lower part of the
gate, and allowing the water to enter above it, is that when the size of
the air-chamber is properly adjusted to the weight of the gate, there
need not come on the wheels, while moving, more than a trifling amount
of weight.
[180] The arrangements of a buoyant gate have been explained above, p.
429.
[181] In the year 1856 and afterwards, Mr. Brunel was engaged in
improving the navigable channel of the river Neath, at its embouchure
into the Bristol Channel. A bank of furnace slag, for directing the
course of the river, had been made previously by Mr. Palmer, and
continued as far seawards as it was then thought could be done with
safety. Mr. Brunel carried a training bank still farther, and succeeded
in cutting off a bend of the river; Mr. Brereton has since extended the
navigable channel in a straight line to low-water mark, a distance of
two miles; and the bar has been lowered to within 1 foot of the level of
the dock sill.
[182] Reports on the Paris Universal Exhibition 1867 vol. i., p. xxiv.
194
[183] When, at the close of the Exhibition, Mr. Brunel was compelled,
much against his will, to accept a pecuniary acknowledgment of his
services, he spent the money in the erection of model cottages at
Barton, a village near his property in Devonshire.
[184] See Report of the Select Committee of the House of Commons on
Ordnance, 1863, Minutes of Evidence and Appendix (ordered to be printed
July 23, 1863):--p. 306, Report of Ordnance Select Committee; p. 44,
Statement of Mr. Whitworth; p. 56, Evidence of Mr. Whitworth (Q.
1329-1337); pp. 58, 59, the same (Q. 1385-1410); pp. 402, 403, Papers
delivered in by Mr. Isambard Brunel; p. 110, Further Evidence of Mr.
Whitworth (Q. 2545-2551); p. 112, the same (Q. 2602-2610); p. 548,
Letter from Mr. Westley Richards to Mr. Isambard Brunel.
[185] Captain Claxton, at Mr. Brunel’s desire, went for a voyage in
Messrs. Ruthven’s vessel, the ‘Enterprise,’ in order to test her
performances.
[186] This appears to be the only instance in which Mr. Brunel printed
an account of any of his works.
[187] On this application of tin for the covering of the roof, Dr.
Parkes observes (_Manual of Practical Hygiene_, London, 1869, p.
317):--‘In the Crimean War the roofs of Renkioi Hospital, on the
Dardanelles, were covered with polished tin; it was found, however,
somewhat difficult to place it so as to exclude rain, and the surface
soon became tarnished. The thermometric experiments did not show a
greater lessening of heat than 3° Fahr. below houses not tin-coated.’
[188] ‘At Renkioi, in Turkey, Mr. Brunel supplied square wooden sewers
about 15 inches to the side; they were tarred inside, and acted most
admirably without leakage for fifteen months, till the end of the war.
The water-closets (Jennings’s simple syphon), arranged with a small
water-box below the cistern, to economise water, never got out of order,
and in fact the drainage of the hospital was literally perfect. I have
little doubt such well-tarred wooden sewers would last two or three
years’ (Parkes’s _Manual of Practical Hygiene_, p. 635).
[189] The woodcut, fig. 22, is a reduction of part of this drawing.
[190] The case of Ranger _v._ the Great Western Railway Company.
[191] See above, p. 192.
[192] The remainder of this letter is printed above, p. 192.
[193] Although Mr. Brunel endeavoured, as far as possible, to lay aside
work during his visits to Watcombe, he found occasions for the use of
his mechanical knowledge. He prepared tools for transplanting young
trees; he did not, however, succeed in making them flourish as well as
before they were transplanted, though he attended to the work himself,
and took care that a large amount of earth was moved with the tree. The
bridge of rough poles across the turnpike road between Teignmouth and
Torquay is as good of its kind as his larger works.
[194] On June 10, 1830, when he was twenty-four years old, Mr. Brunel
was elected a Fellow of the Royal Society. He subsequently became a
member of most of the other scientific societies; but he rarely attended
any meetings, except those of the Institution of Civil Engineers.
[195] At the beginning of 1858, on the expiration of Mr. Robert
Stephenson’s term of office as President of the Institution of Civil
Engineers, Mr. Brunel came next in rotation for election; but his
failing health, and the pressure of his professional duties, led him to
request that he might not then be put in nomination.--- See Inaugural
Address of John Fowler, Esq., January 9, 1866.
[196] A drawing of their Nile boat, the ‘Florence,’ which he made for
his daughter, exhibits the same beautiful minuteness which appears in
all his early sketches for the Clifton bridge and Great Western Railway.
[197] Mr. Brunel’s Nile boat, being of iron, could not safely go up the
Cataracts.
[198] A few weeks after Mr. Brunel’s death, a meeting of his friends was
held, when it was determined to raise some memorial to him. A statue was
made by the late Baron Marochetti, and a site for it promised by the
First Commissioner of Works; but it has not yet been erected.
Mr. Brunel’s family, by the permission of the Dean of Westminster, have
placed a memorial window in the north aisle of the nave of Westminster
Abbey.
Along the bottom of the window (which consists of two lights, each 23
feet 6 inches high and 4 feet wide, surmounted by a quatrefoil opening,
6 feet 6 inches across) is the Inscription, ‘IN MEMORY OF ISAMBARD
KINGDOM BRUNEL, CIVIL ENGINEER. BORN APRIL 9, 1806. DEPARTED THIS LIFE,
SEPTEMBER 15, 1859.’ Over this are four allegorical figures (two in each
light): Fortitude, Justice, Faith, and Charity. The upper part of the
window consists of six panels, divided by a pattern work of lilies and
pomegranates. The panels contain subjects from the history of the
Temple. The three subjects in the western light represent scenes from
the Old Testament--viz. the Dedication of the Temple by Solomon, the
Finding of the Book of the Law by Hilkiah, and the Laying the
Foundations of the Second Temple. The subjects in the eastern light are
from the New Testament--viz. Simeon Blessing the Infant Saviour, Christ
Disputing with the Doctors, and The Disciples pointing out to Christ the
Buildings of the Temple. In the heads of each light are angels kneeling,
and in the quatrefoil is a representation of Our Lord in Glory,
surrounded by angels.
The work was placed in the hands of Mr. R. Norman Shaw, architect, who
prepared the general design, arranged the scale of the various figures,
and designed the ornamental pattern work. The figure subjects were drawn
by Mr. Henry Holiday, and the whole design was executed in glass by
Messrs. Heaton, Butler, & Bayne.
[199] Mr. Locke here spoke in feeling language of Mr. Robert Stephenson.
[200] There appears, from the table, to be an immense extent of
paddle-board to this vessel, if the table be correct--greater than the
midship section.
[201] In a Report by Mr. Brunel on improvements in the port of Bristol,
dated December 26, 1839, the following passage occurs: ‘A great change
is unquestionably about to take place in the carriage of merchandise by
sea, a change similar, though possibly not so striking, as that which
has so suddenly been effected by railways in land carriage. To ensure
the speed which the passenger traffic demands, great size in the vessels
is required; in the course of a very few years we shall find Atlantic
steamers desirous of taking 500 or 600 tons of cargo to make up their
draught.’