[Illustration: IK Brunel Signature
Painted by J. C. Horsley, R.A.--Engraved by T. O. Barlow.]
THE LIFE
OF
ISAMBARD KINGDOM BRUNEL,
CIVIL ENGINEER.
BY
ISAMBARD BRUNEL, B.C.L.,
OF LINCOLN’S INN;
CHANCELLOR OF THE DIOCESE OF ELY.
LONDON:
LONGMANS, GREEN, AND CO.
1870.
PREFACE.
I have not attempted to describe the events of my father’s life in
chronological order beyond the end of Chapter III., which brings down
the narrative to the close of 1835, the year in which the Act was
obtained for the Great Western Railway.
Chapter IV. contains a general account of my father’s railway works,
with the exception of the Bridges, which are described in Chapter VII.
The history of the Broad Gauge and of the trial of the Atmospheric
System on the South Devon Railway is given in Chapters V. and VI.
Chapters VIII.--XIII. contain an account of my father’s labours for the
advancement of Ocean Steam Navigation. It will be noted that these
chapters cover the same period as Chapters IV.--VII., namely, from 1835,
the year of the commencement of the Great Western Railway and the ‘Great
Western’ Steam-ship, to 1859, the year of his death, in which the
Saltash Bridge and the ‘Great Eastern’ were both completed.
Chapters VII. (on the Bridges) and XIV. (on the Docks) have been written
by Mr. William Bell, for many years a member of my father’s engineering
staff; and in regard to Chapter V. (on the Broad Gauge), I have to
acknowledge assistance rendered me by Mr. William Pole, F.R.S.
For the Note on the Carbonic Acid Gas Engine which follows Chapter I., I
am indebted to Mr. William Hawes; and for Chapter VI. (on the
Atmospheric System) to Mr. Froude, F.R.S.
I have also printed letters, written to me at my request, relating to
various incidents in my father’s life.
The assistance I received in the preparation of the chapters on Steam
Navigation from my friend the late Captain Claxton, R.N., has been
referred to in the note to p. 234.
I have throughout availed myself of my brother’s professional knowledge.
I have been compelled, in order to bring the work within the compass of
a single volume, to omit much that would otherwise have been inserted,
and I must therefore be held responsible for the general arrangement of
those parts which have been contributed by others, as well as for the
chapters which I have written myself.
Lastly, I desire gratefully to thank those friends who, by supplying me
with materials and revising the proof sheets, have helped me in my
endeavour to make this book, as far as possible, an accurate record of
my father’s life, written in the spirit of which he would have approved.
I. B.
18 DUKE STREET, WESTMINSTER:
_November_, 1870.
CONTENTS.
PAGE
LIST OF REPORTS AND OTHER ORIGINAL DOCUMENTS xvii
LIST OF ILLUSTRATIONS xxvii
CHAPTER I.
_EARLY LIFE._
A.D. 1806--1828.
Birth of Mr. Brunel, April 9, 1806--Sir Marc Isambard Brunel--The Block
Machinery--Mr. Brunel’s School Life--The Thames Tunnel--Sinking of the
Rotherhithe Shaft--Description of the Shield--Extracts from Sir Isambard
Brunel’s Journals from the Commencement of the Thames Tunnel to the date
of the Second Irruption of the River, January 12, 1828--_Note A_: The
Bourbon Suspension Bridges--_Note B_: Experiments with Carbonic Acid
Gas......1
CHAPTER II.
_THE CLIFTON SUSPENSION BRIDGE._
A.D. 1829--1853. ÆTATIS 24--48.
Origin of the Undertaking--The First Competition, November
1829--Description of Mr. Brunel’s Plans--Mr. Telford’s Decision as
Umpire--Mr. Telford’s Design--The Second Competition--Mr. Brunel
appointed Engineer, March 1831--Commencement of the Works, August
1836--Description of the Design--Abandonment of the Works,
1853--Formation of a New Company and Completion of the Bridge,
1864--_Note_: The Hungerford Suspension Bridge.....46
CHAPTER III.
_EARLY HISTORY OF THE GREAT WESTERN RAILWAY._
A.D. 1833--1835. ÆTATIS 27--30.
Sketch of the History of Railways in England prior to 1833--The Stockton
and Darlington--The Liverpool and Manchester--The London and
Birmingham--Proposed Railway between London and Bristol--Mr. Brunel
appointed Engineer, March 7, 1833--Survey of the Line--Unsuccessful
Application to Parliament in 1834--Successful Application in
1835--Reminiscences of Mr. Brunel, 1833-1835--Extract from Mr. Brunel’s
Diary, written at the close of 1835.....61
CHAPTER IV.
_RAILWAY WORKS._
A.D. 1835--1859. ÆTATIS 30--54.
Construction of the Great Western Railway--The Box Tunnel--The Bath and
Bristol Stations--The Paddington Station--The Great Western
Hotel--Branches and Extensions of the Great Western Railway--The Bristol
and Exeter Railway--Railways in Devonshire and Cornwall--Railways to
Basingstoke, to Weymouth, and to Salisbury--In South Wales--In
Ireland--In Italy--In India--Supervision of Works--Mr. Brunel’s
Engineering Staff--His Reputation as a Witness--Reminiscences of Mr.
Brunel, 1835-1838.....79
CHAPTER V.
_THE BROAD GAUGE._
Origin of the Ordinary Gauge of Railways--Adoption by Mr. Brunel of the
Broad Gauge on the Great Western Railway--Reasons for its Adoption--The
Permanent Way--Reports of Mr. Nicholas Wood and Mr. John Hawkshaw,
1838--_Extract from Report of Directors of Great Western Railway
Company_ (December 20, 1838)--Extension of the Broad Gauge System--Break
of Gauge--Royal Commission on the Gauge of Railways, 1845--_Letter of
Mr. Brunel on the Broad Gauge_ (August 6, 1845)--Gauge Act of 1846--The
Mixed Gauge--Report of Railway Commissioners, 1847--Northern Extensions
of the Great Western Railway--Advantages of the Broad Gauge--Partial
Abandonment of the Broad Gauge.....99
CHAPTER VI.
_THE ATMOSPHERIC SYSTEM._
A.D. 1840--1848. ÆTATIS 35--43.
Preliminary Observations--The South Devon Railway--Description of the
Atmospheric System--History of its Introduction prior to 1844--_Report
by Mr. Brunel, recommending its Adoption on the South Devon Railway_
(August 19, 1844)--Examination of this Report--Mr. Brunel’s Evidence
before the Select Committee on Atmospheric Railways, 1845--History of
the Application of the System on the South Devon Railway,
1844-1848--_Report on State of Works_ (August 28, 1847)--_Report on
Causes of Failure_ (August 19, 1848)--Abandonment of the System,
September 1848--_Note_: Comparison of Stationary and Locomotive
Power.....131
CHAPTER VII.
_RAILWAY BRIDGES AND VIADUCTS._
1. Brickwork and Masonry Bridges--Hanwell Viaduct--Maidenhead
Bridge--Flying Bridges--_Letter from Mr. Brunel on Bridge Construction_
(December 30, 1854)--2. Timber Bridges--Sonning Bridge--Bath
Bridge--Stonehouse Viaduct--Bourne Viaduct--St. Mary’s Viaduct--Viaducts
on the South Devon Railway--Ivy-bridge--Viaducts on the South Wales
Railway--Newport--Landore--Viaducts on the Cornwall Railway--St.
Pinnock--Viaducts on the West Cornwall and Tavistock
Railways--Preservation of Timber--3. Cast-iron Bridges--_Letter on Use
of Cast Iron_ (April 18, 1849)--Hanwell Bridge--Experiments on Cast-iron
Girders--_Extract from Letter to Secretary of Commission on Application
of Iron to Railway Structures_ (March 13, 1848)--4. Wrought-iron
Bridges--Girder Bridges--Experiments on Wrought-iron Girder--Opening
Bridges--Trussed Bridges--Newport Viaduct--Windsor Bridge--Chepstow
Bridge--Method of Sinking the Cylinders--Description of the Main
Truss--The Floating Operations--The Royal Albert Bridge at Saltash--The
Centre Pier--Description of the Superstructure--The Floating and Raising
of the Trusses--Opening of the Bridge by H. R. H. the Prince
Consort--_Note_: Experiments on Matters connected with Bridge
Construction.....171
CHAPTER VIII.
_STEAM NAVIGATION. THE ‘GREAT WESTERN’ STEAM-SHIP._
A D. 1835--1847. ÆTATIS 30--42.
Introduction to the Chapters on Steam Navigation--Formation of the Great
Western Steam-Ship Company--Commencement of the Building of the ‘Great
Western’--_Report on Selection of the Builders of the Engines_ (June 18,
1836)--Statements of Dr. Lardner on the probable Failure of a line of
Steam-ships between England and America--Voyage of the ‘Great Western’
to London--Completion of the Engines--Her return to Bristol--Fire on
Board, and Accident to Mr. Brunel--Voyage to New York--Comparison
between the Performances of the ‘Great Western’ and the
‘Sirius’--Subsequent History of the ‘Great Western’--_Note_: Dimensions
of the Ship and Engines.....231
CHAPTER IX.
_STEAM NAVIGATION. THE ‘GREAT BRITAIN’ STEAM-SHIP._
A.D. 1838--1847. ÆTATIS 33--42.
Commencement of the building of the ‘Great Britain’--_Report on the
Engines_ (June 13, 1839)--Experiments on the Screw Propeller--Its
Adoption in the ‘Great Britain’--Completion of the Ship--Her Voyage
across the Atlantic--Stranding of the ‘Great Britain’ in Dundrum
Bay--_Letter to Captain Claxton on the Condition of the ‘Great Britain’
and on the Means to be adopted for saving her_ (December 10,
1846)--_Report to the Directors on the same Subject_ (December 14,
1846)--Appointment of Captain Claxton to superintend the Execution of
Mr. Brunel’s Plans--_Letter to Captain Claxton on the Difficulties to be
overcome_ (December 29, 1846)--_Report enclosing Captain Claxton’s
Account of the Erection of the Breakwater_ (February 27, 1847)--_Report
on the Arrangements for Floating off the Ship_ (May 4, 1847)--Successful
Accomplishment of the Floating Operations--Subsequent History of the
‘Great Britain’--_Note_: Dimensions of the Ship and Engines.....246
CHAPTER X.
_STEAM NAVIGATION. INTRODUCTION OF THE SCREW PROPELLER INTO THE ROYAL
NAVY._
A.D. 1841--1844. ÆTATIS 36--39.
Appointment of Mr. Brunel to conduct Experiments for the Admiralty with
various Forms of the Screw Propeller, April 1841--Trials with the
‘Polyphemus’--Opposition to Mr. Brunel’s Experiments--Trials with the
‘Rattler’, October 1843--October 1844.....283
CHAPTER XI.
_STEAM NAVIGATION. THE ‘GREAT EASTERN’ STEAM-SHIP, FROM THE COMMENCEMENT
OF THE UNDERTAKING TO THE LAUNCH._
A.D. 1851--1857. ÆTATIS 46-52.
Introductory Observations--The Australian Steam Navigation
Company--_Statement of Mr. Brunel’s Project of a Line of large Ships_
(June 10, 1852)--Adoption of his Plans by the Eastern Steam Navigation
Company--_Extract from a Letter describing the Scheme_ (July 1,
1852)--_Letter to J. Scott Russell, Esq., on the Form and Dimensions of
the Great Ship_ (July 13, 1852)--_Report on Mode of Proceeding_ (July
21, 1852)--_Report on Enquiries Relating to the Draught and Form of the
Vessel_ (October 6, 1852)--_Report on the Proceedings of the Committee
appointed to consider Mr. Brunel’s Plans_ (March 21, 1853)--Tenders
invited for the Ship and Engines--_Report on Tenders_ (May 18,
1853)--Preparation of the Contracts and Specifications--_Extracts from
Mr. Brunel’s Memoranda_ (A.D. 1852, 1853, 1854)--_Letter on his Position
and Duties as Engineer of the Company_ (August 16, 1854)--_Letter on an
Article in a Newspaper_ (November 16, 1854)--_Report on the Undertaking_
(February 5, 1855)--Arrangements proposed for obtaining Astronomical
Observations--_Letter to G. B. Airy, Esq., Astronomer Royal_ (October 5,
1852)--Appointment of Mr. William Harrison to the Command of the
Ship--_Memorandum on the Management of the Great Ship_ (October
1855)--_Letter on the Duties of the Chief Engineer_ (March 19,
1857)--Suspension and Resumption of the Works.....289
CHAPTER XII.
_STEAM NAVIGATION. THE ‘GREAT EASTERN’ STEAM-SHIP. THE LAUNCH._
A.D. 1857, 1858. ÆTATIS 52.
Determination that the Ship should be launched broadside to the
River--And that the Launch should be slow--_Extracts from Mr. Brunel’s
Report of February 1855_--Reasons for the Adoption of Iron Sliding
Surfaces--Description of the Ways and Cradles--And of the Motive Power
provided for launching the Ship--_Memorandum on proposed Arrangements
for the Launch_ (September 26, 1857)--_Letter to Captain Harrison on
River Tackle_ (September 30, 1857)--_Letter on the Nature of the
Operations_ (October 23, 1857)--_Memorandum on general Arrangements and
intended Mode of Proceeding_ (October 30, 1857)--History of the Launch,
Nov. 3, 1857 to January 31, 1858--_Letter to the Directors_ (November
26, 1857)--_Report and Memorandum on the Launching Operations_ (December
17, 1857)--Floating the Ship--_Note A_: Experiments and Observations on
Friction--_Note B:_ Letter to W. Froude, Esq. (February 2, 1858).....340
CHAPTER XIII.
_STEAM NAVIGATION. THE ‘GREAT EASTERN’ STEAM-SHIP. COMPLETION AND
SUBSEQUENT HISTORY._
A.D. 1858, 1859. ÆTATIS 52-54.
A.D. 1859-1870.
Preparations for completing the Ship--Formation of the Great Ship
Company--Mr. Brunel’s Absence from England--Progress of the Works from
his Return to his last Illness--Voyage to Weymouth--Explosion of
Water-Heater--Storm at Holyhead--Description of the Ship--Her first
Voyage to New York, June 1860--Second Voyage to New York, May
1861--Voyage with Troops to Quebec, June 1861--Fracture of Rudder Head
and Destruction of Paddlewheels, September 1861--Voyages in
1862--Accident off Montauk Point, August 27, 1862--Voyages in
1863--Formation of the Great Eastern Steam-Ship Company--Remarks on the
History of the ‘Great Eastern’ previous to her Employment in laying
Submarine Telegraph Cables--Telegraph Expeditions of 1865 and
1866--French Cable Expedition of 1869--Voyage to Bombay and Aden, 1869,
1870--Concluding Remarks--_Note_: Dimensions of the Ship and
Engines.....392
CHAPTER XIV.
_DOCK AND PIER WORKS._
A.D. 1831--1859. ÆTATIS 26--54.
Monkwearmouth Docks, 1831--Bristol Docks--Floating Harbour,
1832--Proposed Works at Portishead--New Lock at Bristol, 1845--Bristol
Dock Gates--Plymouth Great Western Docks, 1847--Briton Ferry Docks,
1851--Brentford Dock, 1856--Pier at Milford Haven, 1857.....417
CHAPTER XV.
_MISCELLANEOUS WORKS._
The Great Exhibition of 1851--The Crystal Palace Water Towers,
1853--Polygonal Rifle, 1852--Gunnery Experiments, 1854--Floating
Gun-Carriage, 1854--Renkioi Hospital Buildings, 1855.....445
CHAPTER XVI.
_MR. BRUNEL’S PROFESSIONAL OPINIONS AND PRACTICE._
Scheme of the Chapter--Mr. Brunel’s Position in relation to the
Companies of which he was Engineer--_Letter on the Direction of Railway
Works in Italy_ (March 4, 1845)--_Letter on the Position of Joint
Engineer_ (October 16, 1843)--_Letter on the Position of Consulting
Engineer_ (December 30, 1851)--_Letter on the Position of the Engineer
in relation to the Contractors_ (May 26, 1854)--_Letters on the Position
of the Engineer in relation to the Directors_ (April 15, 1850, December
6, 1851, January 22, 1857)--Mr. Brunel’s Assistants--_Letters on
Interference of Directors with the Assistant Engineers_ (January 19,
1842, January 28, 1842, January 12, 1851)--Mr. Brunel’s Pupils--His
Relations with other Engineers--Inventors--_Letter in reply to an
Inventor_ (September 17, 1847)--Mr. Brunel’s Views as to State
Interference--_Letter on the Royal Commission on the Application of Iron
to Railway Structures_ (March 13, 1848)--_Letter on a Proposal to obtain
the Recognition in England of Decorations conferred at the Paris
Exhibition of 1855_ (February 9, 1856)--Mr. Brunel’s Opinion on the
Patent Laws--_Memorandum for Evidence before the Select Committee of the
House of Lords on the Patent Laws, 1851_--_Extract from Observations on
the Patent Laws, made by Mr. Brunel at a Meeting of the Society of
Arts,_ March 26, 1856.....474
CHAPTER XVII.
_PRIVATE LIFE._
Reminiscences of Mr. Brunel’s Private Life--Removal to 18 Duke Street,
Westminster--His Marriage, 1836--Special Constable in 1848--Mr. Brunel’s
Love of Art--His Journey to Italy, 1842--Accident with the
Half-Sovereign, 1843--Purchase of Property in Devonshire, 1847--His life
at Watcombe--The Launch of the ‘Great Eastern,’ 1857--Mr. Brunel’s
Failing Health--Journeys to Switzerland and Egypt, 1858--_Letter from
Philæ_ (February 12, 1859)--His last Illness--His Death, September 15,
1859--Funeral--Address of Joseph Locke, Esq., M.P., at the Institution
of Civil Engineers, November 8, 1859.....499
APPENDIX I.
Report to the Directors of the Great Western Railway on the Broad Gauge,
&c. (August 1838).....525
APPENDIX II.
Report to the Directors of the Great Western Steam-Ship Company,
recommending the Adoption of the Screw Propeller in the ‘Great Britain’
Steam-ship (October 1840).....539
INDEX.....559
LIST
OF
REPORTS AND OTHER ORIGINAL DOCUMENTS.
PAGE
1. Extract from Mr. Brunel’s Diary (December 26, 1835).....78
2. Letter on the Box Tunnel (June 21, 1842).....81
3. Extract from Report to Directors of the Great Western Railway Company
on Break of Gauge (December 13, 1838).....105
4. Extract from Report to Directors of the Great Western Railway Company
on the Permanent Way (February 1837).....109
5. Letter on various Points relating to the Broad Gauge (August 4,
1845).....120
6. Extract from Letter on Atmospheric System (April 8, 1844).....137
7. Report to the Directors of the South Devon Railway Company,
recommending them to adopt the Atmospheric System (August 19,
1844).....138
The question had been frequently considered by him (p. 138)--Stationary
power is cheaper and otherwise better than locomotive power (p.
138)--The Atmospheric System is a good, economical mode of applying
stationary power (p. 138)--Reasons for considering it applicable to the
South Devon Railway (p. 139)--In the construction of the line (p.
140)--In the subsequent working (p. 141).
8, 9. Letters on giving Evidence before the Select Committee of the
House of Commons on the Atmospheric System (March 31, 1845; April 3,
1845).....145
10. Report to the Directors of the South Devon Railway on the State of
the Atmospheric Apparatus (August 27, 1847).....149
Regret at postponement of working (p. 149)--Which has been caused by
delay in completion of the engines (p. 149)--Experimental trains have
run (p. 149)--Difficulties have exceeded all just anticipations (p.
150).
11. Report to a Committee of the Directors of the South Devon Railway
Company on the Causes of the Failure of the Atmospheric System (August
19, 1848).....159
The first difficulty has been in the stationary engines, which have
consumed an excessive amount of fuel (p. 159)--The difficulties in the
working of the longitudinal valve have been more numerous (p. 161)--The
principal evil might be remedied in a new valve (p. 162)--An extension
of the system beyond Newton cannot be recommended (p. 162)--The delay in
obtaining the telegraph has been a great disappointment (p. 163).
12. Letter on the Design of Engineering Works (December 30,
1854).....178
13. Extract from Letter on the Use of Cast Iron in Bridge Construction
(April 18, 1849).....190
14. Extract from Letter on the same Subject (March 13, 1848).....192
15, 16, 17. Extract from Letters on Bridges of Large Spans (January 31,
1852; December 1, 1852; May 30, 1854).....212
18. Extract from Report on the Cornwall Railway as to making the Saltash
Bridge for a Single Line (February 5, 1852).....214
19. Report to the Directors of the Great Western Steam-Ship Company on
the Selection of the Builders of the Engines for the ‘Great Western’
Steam-ship (June 18, 1836).....235
Every means must be taken to secure the best engines possible in this
the boldest attempt yet made (p. 235)--The peculiar conditions required
in these engines (p. 235)--They must, as far as is possible, be perfect
in all their details from the moment of their completion (p. 235)--The
machinery required is by no means an ordinary steam-engine (p.
236)--Modifications necessary in designing engines of so large a size
(p. 236)--Reasons based on these considerations for preferring Messrs.
Maudslay and Field as builders of these engines (p. 236).
20. Letter on the Engines for the ‘Great Britain’ Steam-ship (June 12,
1839).....249
Both the plans of Messrs. Maudslay and Field and Mr. Humphrys are
adapted to the case, and the choice will depend upon the relative cost
and advantages of forming an establishment to build the engines, and
that of having the skill of experienced manufacturers (p. 249).
21. Letter to T. R. Guppy, Esq., on the Construction of Iron Ships
(August 3, 1843).....259
22. Extract from Letter on the ‘Great Britain’ Steam-ship (December 11,
1844).....261
23. Letter to Captain Claxton on the State of the ‘Great Britain’
Steam-ship (December 10, 1846).....264
24. Report on the Condition of the ‘Great Britain’ Steam-ship when
stranded in Dundrum Bay (December 14, 1846).....267
The ship is, apart from mere local damage, perfectly sound, which would
not have been the case had she been built of timber (p.
267)--Description of her injuries (p. 268)--Consideration of the best
means of recovering the property invested in her--It would not be
profitable to break her up (p. 268)--How, then, is the vessel to be got
into port? (p. 269)--This question is secondary to that of how she is to
be preserved until she can be removed (p. 269)--A stiff timber
breakwater would not stand, even if it could be safely constructed (p.
269)--The best plan is to form under the stern and along the exposed
side of the ship a mass of fagots (p. 270)--And in order to preserve the
ship, this must be done without delay (p. 270)--As to floating her off,
she should be lifted and made water-tight (p. 271)--But she must first
be preserved (p. 272).
25. Letter to Captain Claxton on the Breakwater (December 29,
1846).....272
26. Report enclosing Captain Claxton’s Account of the Proceedings at
Dundrum (February 27, 1847).....273
Success achieved by Captain Claxton in constructing the breakwater of
fagots (p. 273)--Introduction by him of several important alterations
and improvements in the plans proposed (p. 274).
27. Report on the proposed Means of Floating the ‘Great Britain’
Steam-ship (May 4, 1847).....278
The ship has been successfully protected and lifted, and made
water-tight, so that the operation of floating by camels becomes more
practicable (p. 279)--The Directors would do well to call in Mr. Bremner
to advise them (p. 280).
28. Extract from Letter relating to Proceedings at the Admiralty as to
the Screw Propeller (July 8, 1842).....283
29. Extract from Letter on the same Subject (August 6, 1842).....286
30. Statement of Project for a Line of large Steam-ships (June 10,
1852).....292
The principle advocated is that of making the vessel large enough to
carry her own coal for the voyage, just as the ‘Great Western’
steam-ship did in 1838 (p. 292)--The size being limited only by the
extent of demand for freight, and by the circumstances of the ports to
be frequented (p. 292).
31. Extract from Letter describing the Project of the Great Ship (July
1, 1852).....293
32. Letter to J. Scott Russell, Esq., on the Form and Dimensions of the
Great Ship (July 13, 1852).....294
33. Report to the Directors of the Eastern Steam Navigation Company on
mode of Proceeding (July 21, 1852).....296
34. Report on Enquiries relating to the Draught and Form of the Great
Ship (October 6, 1852).....297
35. Report on the Dimensions of the Great Ship (March 21, 1853).....299
36. Report on the Tenders for the Ship and Engines (May 18,
1853).....301
A short specification was drawn up for the engines, and detailed
drawings and specifications for the ship (p. 301)--Tenders have been
received for the engines from Mr. J. Scott Russell, Messrs. Watt and
Co., and Mr. Humphrys (p. 302)--After frequent communications with these
gentlemen, Messrs. Watt and Co.’s designs are preferred for the screw
engines, which will be the largest yet made, and on which will mainly
depend the performances of the ship (p. 302), and Mr. J. Scott Russell’s
for the paddle engines (p. 302)--As regards a tender for the ship, after
communications with several parties, the result is a tender from Mr. J.
Scott Russell (p. 303).
37. Extracts from Mr. Brunel’s Memoranda relating to the ‘Great Eastern’
Steam-ship (July 11, 1852, to November 18, 1853).....304
July 11, 1852: Dimensions of the ship (p. 304)--Division of power
between the screw and paddle engines (p. 305)--Every known means must be
adopted to ensure efficiency (p. 305)--Jacketing of steam pipes, &c. (p.
305). July 17, 1852: Conference with Mr. Field as to division of power
between the screw and paddle engines (p. 305)--Pressure of steam (p.
305)--Nothing uncertain must be risked (p. 305)--Jacketing (p. 305).
July 19, 1852: Strong bulkheads every 30 feet or thereabouts, and the
main ribs, and even at least two main deck beams, to be longitudinal,
instead of transverse (p. 305). February 2, 1853: Present views as to
the construction of the ship and engines (p. 306)--Boilers (p.
307)--Advantages of oscillating engines for both screw and paddle
engines (p. 307). February 21, 1853: Proper dimensions for the Calcutta
line (p. 308)--Gas (p. 308)--Ventilation (p. 308)--Steering (p. 308).
March 14, 1853: Dimensions now determined on (p. 308). March 22, 1853:
Various dimensions settled (p. 308). April 28, 1853: Tenders are being
sought for (p. 308)--Arrangements for measuring the coal (p. 309)--Use
of clean water (p. 309). August 7, 1853: Memoranda for engines (p. 309).
November 18, 1853: Governors (p. 309)--Auxiliary engine and boiler (p.
309).
38. Extracts from Mr. Brunel’s Memoranda relating to the ‘Great Eastern’
Steam-ship (February 25 to March 10, 1854).....310
February 25, 1854: Thought and labour involved in the details of the
construction both of the ship and engines (p. 310)--Cabin arrangements
(p. 310)--Economy of material in the construction of the ship (p.
310)--A matter generally neglected in shipbuilding (p. 310)--All this
misconstruction forbidden (p. 311). March 3, 1854: Details of screw
engines (p. 311). March 10, 1854: Details of ship (p. 311).
39. Letter to the Secretary of the Eastern Steam Navigation Company, on
Position as Engineer of the Company (August 16, 1854).....311
His unusual stake in the undertaking, and the heavy responsibility he
has incurred (p. 311)--The work is one which requires that it should be
entirely under his individual management and control (p. 312)--And
therefore there must be no other adviser or source of information on any
question connected with the construction or mode of carrying out the
work (p. 312).
40. Letter to the same on an Article in a Newspaper (November 16,
1854).....313
His general rule is not to notice newspaper articles, but this one bears
the stamp of authority (p. 313)--Marked care is shown in depreciating
his former efforts in advancing steam navigation, and in representing
him, in the present case, as the passive approver of the project of
another (p. 313)--Whereas it originated solely with him, and has been
worked out by him with great thought and labour (p. 314).
41. Report to the Directors of the Eastern Steam Navigation Company,
describing the Nature of the Undertaking (February 5, 1855).....315
Labour of preparing the preliminary designs for the ship (p.
316)--[Proposed arrangements for launching]--Principal peculiarities in
the construction of the ship (p. 316)--Water-tight compartments (p.
316)--Transverse bulkheads (p. 316)--Double skin (p. 317)--Longitudinal
bulkheads (p. 318)--Economy in materials (p. 318)--Engines (p.
318)--Boilers (p. 319)--The best advice has been sought on every point
(p. 319)--The position and design of the paddlewheels (p. 319)--The
screw propeller--(p. 320)--Protection from fire (p. 320)--Masts and
sails (p. 320)--Astronomical observations (p. 320)--Lightning conductors
(p. 321)--Adjustment of compasses (p. 321).
42. Letter to G. B. Airy, Esq., Astronomer Royal (October 5,
1852).....321
As so much depends on perfect navigation, every means is to be taken to
ensure a constant determination of the ship’s position and course (p.
321)--It is proposed to have an observatory and staff of observers to be
constantly engaged in taking observations (p. 322)--What should be the
nature of these observations and of the instruments required? (p. 322).
43. Memorandum on the Management of the Great Ship (October
1855).....324
The principles to be followed in the use of this new machine, and the
qualifications of the commander, have long been a subject of anxious
consideration by him (p. 324)--This ship requires a totally different
management from that suited to ordinary vessels (p. 325)--Examples of
this proposition (p. 326)--Size of the great ship (p. 326)--By no
possibility must she be allowed to touch the ground (p. 327)--Probable
effects of the great size and mass of this vessel (p. 329)--And of her
speed (p. 330)--The proposed system of continuous observation (p.
330)--The exact course the ship is to take must be determined previously
to the voyage, and must be strictly adhered to (p. 331)--Economy of fuel
another consideration of the highest importance (p. 332)--Proper speed
of the engines (p. 332)--Use of the sails (p. 333)--Peculiarities of the
position of the commander (p. 333)--His attention must be devoted
exclusively to the general management of the system by which the ship is
to be made to go like a piece of machinery (p. 333)--His assistants (p.
334)--Four chief officers (p. 334)--A master at the head of a staff of
observers, who are to make continuous observations upon the position and
performances of the ship (p. 334)--The chief engineer (p. 335)--The
principles herein set out are to be adopted by the commander as the
guide of his conduct in working this machine (p. 335).
44. Letter on the Responsibility of his Position (sent with
last).....324
45. Letter on the Duties of the Chief Engineer of the Great Ship (March
19, 1857).....335
The success of the ship as a steamboat will depend entirely upon the
amount of power developed by the engines in proportion to the fuel
consumed (p. 336)--The peculiar duties of the chief engineer will be to
obtain the largest amount of steam from the defined expenditure of fuel,
and the use of this steam so as to obtain the largest amount of power
and the largest amount of result (p. 337)--Accurate measurements
required of fuel expended and results obtained (p. 337)--Economy in
every department may make the difference between the success and failure
of the ship (p. 337)--The chief engineer should, if possible,
superintend the erection of the engines (p. 338).
46. Extract from Report to the Directors of the Eastern Steam Navigation
Company, describing the proposed Arrangements for Launching (February 5,
1855).....341
Reasons for deciding to launch the ship sideways (p. 341)--And probably
gradually (p. 342).
47. Extract from Memorandum as to Power required to move the Ship
(September 26, 1857).....352
48. Letter to Captain Harrison on the River Tackle (September 30,
1857).....354
49. Letter to the Directors of the Eastern Steam Navigation Company on
the Nature of the Launching Operations (October 23, 1857).....355
The date is uncertain (p. 355)--The ship is to be lowered down and
floated off by a slow and laborious operation (p. 355)--She may stop or
not move at all (p. 356).
50. Memorandum on General Arrangements and intended Mode of Proceeding
in the Launching Operations (October 30, 1857).....356
51. Letter to the Directors of the Eastern Steam Navigation Company on
the State of the Operations (November 26, 1857).....366
52. Letter to the Directors, and Memorandum on the State of the
Operations (December 17, 1857).....377
53. Letter to W. Froude, Esq., describing the Floating of the ‘Great
Eastern’ (February 2, 1858).....389
54. Extract from Report to the Directors of the Bristol Dock Company on
the Condition of the Floating Harbour (August 31, 1832).....423
55. Extract from Report on the same subject (January 31, 1842).....424
56. Extract from Report on Portishead Pier (December 26, 1839).....427
57. Letter on the Distribution of Prizes, addressed to the Chairman of
the Committee of the Section of Machinery of the Exhibition of 1851
(March 11, 1850).....445
58. Extract from Report of the Jury of Class VII. of the Exhibition of
1851 on Sir Joseph Paxton’s Design for the Building.....447
59, 60, 61. Letters to Westley Richards, Esq., on the Polygonal Rifle
(October 25, 1852; February 7, 1853; November 26, 1858).....450-1
62. Extract from Letter to James Nasmyth, Esq., on the Construction of
Large Guns (April 2, 1855).....452
63. Extract from Letter to W. G. Armstrong, Esq., on the Wire Gun (June
8, 1855).....454
64. Memorandum on the Floating Gun-Carriage (December 20, 1855).....455
The principle is fixing a very heavy gun in a floating shot-proof
chamber (p. 455)--Mode of working the gun (p. 455)--Mode of manœuvring
the vessel (p. 456)--Mode of attacking the Baltic forts with a fleet of
such vessels (p. 457)--Thickness of iron required to make the vessel
shot proof (p. 458)--Best manner of constructing the vessels (p. 458).
65. Letter to the Secretary of the Admiralty on the Floating
Gun-Carriage (July 27, 1855).....459
66. Memorandum on Renkioi Hospital Buildings (March 1855).....463
Necessary conditions in designing these buildings (p. 463)--General
description of them (p. 463)--Closets and lavatories (p. 464)--External
and internal covering (p. 464)--Ventilation (p. 464)--Kitchens (p.
465)--Drainage (p. 466)--Officers’ quarters (p. 466)--Transport of
materials (p. 466)--Portable baths (p. 467)--Cost of buildings (p.
467).
67. Letter on the Direction of Railway Works (March 4, 1845).....475
68. Letter on the Position of Joint Engineer (October 16, 1843).....476
69. Letter on the Position of Consulting Engineer (December 30,
1851).....477
70. Letter on the Position of the Engineer in relation to the
Contractors (May 26, 1854).....477
71, 72, 73. Extracts from Letters on the Relations between the Engineer
and the Directors (April 15, 1850; December 6, 1851; Jan. 22,
1857).....478-481
74, 75, 76. Extracts from Letters on Interference of Directors with the
Assistant Engineers (January 19, 1842; January 28, 1842; December 12,
1851).....481-3
77. Extract from Diary (May 5, 1846).....485
78. Letter to an Inventor (September 17, 1847).....486
79. Letter on the Royal Commission on the Application of Iron to Railway
Structures (March 13, 1848).....486
80. Letter on a Proposal to obtain Recognition in England of Decorations
conferred at the Paris Exhibition of 1855 (Feb. 9, 1856).....489
81. Memorandum for Evidence before the Select Committee of the House of
Lords on the Patent Laws, A.D. 1851.....490
He has had large experience of the patent laws (p. 490)--Has never taken
out one, and is of opinion that the system is productive of immense evil
(p. 491)--Reasons for this belief (p. 491)--Conditions necessary for a
successful patent (p. 493)--Disadvantages of patents (p.
494)--Impediments in the way of improvements (p. 495).
82. Extract from Observations on the Patent Laws made by Mr. Brunel at a
Meeting of the Society of Arts (March 28, 1856).....497
83. Letter from Philæ, describing the Ascent of the Cataracts (February
12, 1859).....517
84. Report to the Directors of the Great Western Railway Company on the
Broad Gauge, &c. (August 1838).....525
He is desirous of combining his views into one report (p. 525)--The
difficulties have been overcome, or are gradually diminishing (p.
525)--And the result justifies the attempt which has been made (p.
526)--The gradients of the Great Western Railway are favourable (p.
526)--Advantages of the broad gauge (p. 527)--Reasons for adopting it
(p. 528)--Additional cost in construction is very slight (p.
529)--Weight of carriages (p. 530)--Freedom from accidents (p.
531)--Greater space for works of locomotives (p. 532)--The greater width
gives scope for improvement in every part (p. 532)--Speed obtained (p.
532)--Design of the engines (p. 533)--The continuous system of permanent
way is best adapted to high speeds (p. 535)--Calculations as to its cost
compared with that of a well constructed line with stone blocks (p.
537).
85. Report to the Directors of the Great Western Steam-Ship Company,
recommending the Adoption of the Screw Propeller in the ‘Great Britain’
Steam-ship (October 1840),.....539
This subject will be considered under two heads: 1. The efficiency of
the screw propeller, compared with the paddlewheel. 2. The advantages or
disadvantages attending its use (p. 539)--The first question involves
the consideration not merely of the effect produced, but also of the
proportionate power absorbed in producing that effect (p.
539)--Observations on the slip of the paddlewheel and screw in the
‘Great Western’ and ‘Archimedes,’ respectively (p. 540)--The result of
the comparison being, that with similar areas the screw will meet with
at least equal, if not a greater resistance, and will consequently slip
as little as or less than the ordinary paddle-board (p. 542)--Refutation
of the common error, that the action of the screw is a very oblique one,
and that it imparts a considerable rotatory motion to the water (p.
543)--Description of the action of the screw (p. 543)--The result of the
experiments is that, as compared with the ordinary paddlewheel of
sea-going steamers, the screw is, both as regards the effect produced
and the proportionate power required to obtain that effect, an efficient
propeller (p. 548)--Objections to the use of the screw propeller (p.
548)--Answered seriatim (p. 549)--Statement of the principal advantages
peculiar to the use of the screw (p. 552)--The result of these enquiries
is a strong and decided opinion in favour of the screw propeller being
adopted in the ‘Great Britain’ steam-ship (p. 557).
LIST
OF
ILLUSTRATIONS.
_ENGRAVINGS._
Portrait (engraved with permission of Messrs. Graves and Company by
T. O. Barlow, from a portrait by J. C. Horsley, R.A., in the possession
of Mrs. Brunel). ....._Frontispiece_
PLATE. ....._to face_ PAGE
I. The Clifton Suspension Bridge.....49
II. The Hungerford Suspension Bridge.....59
III. The Royal Albert Bridge at Saltash. General View......171
IV. The Newport, Windsor, and Chepstow Bridges. Elevations
and Sections.....206
V. The Royal Albert Bridge at Saltash. Elevations and Sections......218
_WOODCUTS._
FIG. .....PAGE
1. Maidenhead Bridge (longitudinal section).....174
2. Bourne Viaduct (outline elevation).....181
3. Ivybridge Viaduct (the same).....182
4. Landore Viaduct (the same).....184
FIG. PAGE
5. St. Pinnock Viaduct (outline elevation, transverse section, and
plans of piers).....187
6. Experimental Girder (transverse section).....193
7. Girder on South Wales Railway (the same).....194
8. Girder on Eastern Bengal Railway (the same).....195
9. Cumberland Basin Swing Bridge (transverse section of girder).....196
10. Windsor Bridge (transverse section of truss).....200
11. Chepstow Bridge (the same).....208
12. Saltash Bridge (the same).....219
13. Transverse Section of the ‘Great Britain’ Steam-Ship.....256
14. Copy of a Sketch in a Letter on Iron Ships.....259
15. Transverse Section of the Cradles and the Launching Ways of
the ‘Great Eastern’ Steam-Ship.....347
16. Longitudinal Section, Plan, and Midship Section of the ‘Great
Eastern’ Steam-Ship.....397
17. Monkwearmouth Dock Gates.....421
18. Bristol Dock Gate.....430
19. Plymouth Great Western Dock Gates.....435
20. Briton Ferry Dock Gate.....439
21. Brentford Dock Gate.....441
22. Renkioi Hospital.....470
LIFE
OF
ISAMBARD KINGDOM BRUNEL.
CHAPTER I.
_EARLY LIFE._
A.D. 1806--1828.
BIRTH OF MR. BRUNEL, APRIL 9, 1806--SIR MARC ISAMBARD BRUNEL--THE
BLOCK MACHINERY--MR. BRUNEL’S SCHOOL LIFE--THE THAMES
TUNNEL--SINKING OF THE ROTHERHITHE SHAFT--DESCRIPTION OF THE
SHIELD--EXTRACTS FROM SIR ISAMBARD BRUNEL’S JOURNALS FROM THE
COMMENCEMENT OF THE THAMES TUNNEL TO THE DATE OF THE SECOND
IRRUPTION OF THE RIVER, JANUARY 12, 1828--_NOTE A:_ THE BOURBON
SUSPENSION BRIDGES--_NOTE B:_ EXPERIMENTS WITH CARBONIC ACID GAS.
ISAMBARD KINGDOM BRUNEL was born on the ninth day of April, 1806, at
Portsmouth, and was the only son of Sir Marc Isambard Brunel.[1]
Most biographies commence with an account of the parentage of the person
whose life is about to be written. If this be permitted in any case, no
apology can be needed for prefixing to a Life of Mr. Brunel some
particulars of his father’s career, since he was indebted to him, not
only for the inheritance of many natural gifts, and for a professional
education such as few have been able to procure, but also for a bright
example of the cultivation of those habits of forethought and
perseverance, which alone can ensure the successful accomplishment of
great designs.
Sir Marc Isambard Brunel was a native of Hacqueville, a village in
Normandy, where his family had been settled for several generations. He
was originally intended for the priesthood; but, as he showed no
inclination for that calling, and a very decided talent for mechanical
pursuits, he was permitted to enter the French Navy; and he served in
the West Indies for six years, namely, from 1786 to 1792. On his return
home, at the expiration of his term of service, his strong Royalist
sympathies made it unsafe for him to remain in France, and with great
difficulty he managed to escape to America. He landed at New York in
September 1793, and soon obtained employment as a civil engineer. A few
years afterwards he was appointed engineer to the State of New York;
and, while holding that office, he designed a cannon foundry and other
important public works.
In January 1799, when Sir Isambard was in his thirtieth year, he came
over to England, and shortly after his arrival married Miss Sophia
Kingdom, a lady for whom he had formed an attachment some years
before.[2]
The first great work undertaken by him in this country was the machinery
for making blocks, which he designed and erected for Government at
Portsmouth.
The history of the invention and construction of this system of
machinery (for it consisted of _forty-three_ separate machines) need not
be given at length; but it may be permitted to extract the following
passage from Mr. Beamish’s ‘Life of Sir Isambard Brunel’ (pp. 97, 99,
2nd edition), in which he points out the benefits which have resulted
from its introduction, and the position its inventor is entitled to hold
among those who have contributed to the progress of mechanical science.
Where fifty men were necessary to complete the shells of blocks
previous to the erection of Brunel’s machinery, four men only are
now required, and to prepare the sheaves, six men can now do the
work which formerly demanded the labours of sixty. So that ten men,
by the aid of this machinery, can accomplish with uniformity,
celerity, and ease, what formerly required the uncertain labour of
one hundred and ten.
When we call to mind that at the time these works were executed,
mechanical engineering was only in its infancy, we are filled with
amazement at the sagacity and skill that should have so far
anticipated the progress of the age, as to leave scarcely any room,
during half a century, for the introduction of any improvement....
Beautiful as are the combinations and contrivances in the block
machinery, and highly deserving as the inventor may be of credit
for originating such labour-saving machines for the production of
ships’ blocks, there is a far higher claim to the admiration and
gratitude of all constructors of machinery, and of all workers in
metal. In this block machinery exist the types and examples of all
the modern self-acting tools, without the aid of which the various
mechanical appliances of the present day could not be produced with
the marvellous accuracy which has been attained. It is true that to
the trades unions or combinations among the artisans, is in a great
measure directly due the introduction of self-acting machines; but
the types of all these tools existed in the machines and
combinations of Brunel’s block machinery. The drilling, the
slotting, and the shaping machines, the eccentric chuck, and the
slide rest, with the worm wheel motion, are all to be found in his
machine.
On the completion of the block machinery Sir Isambard Brunel removed to
London, and took a house in Lindsay Row, Chelsea, where he remained
until he was obliged to live nearer the works of the Thames Tunnel.
Mr. Brunel’s first recollections were of the house at Chelsea; and in
1814, when he was eight years old, he commenced his school life under
the Rev. Weeden Butler, who resided in the neighbourhood. Previously to
his going to Mr. Butler, he had been taught Euclid by Sir Isambard; and
he had also a great talent for drawing, for which he had been remarkable
even from four years old. His drawings were beautifully precise and
neat, but, when the subject admitted of it, full of vigour and
picturesque effect.
After some time he was sent to Dr. Morell’s school at Hove, near
Brighton. The following extract is taken from one of his letters home in
1820:--
I have past Sallust some time, but I am sorry to say I did not read
all, as Dr. Morell wished me to get into another class. I am at
present reading Terence and Horace. I like Horace very much, but
not as much as Virgil. As to what I am about, I have been making
half a dozen boats lately, till I have worn my hands to pieces. I
have also taken a plan of Hove, which is a very amusing job. I
should be much obliged to you if you would ask papa (I hope he is
quite well and hearty), whether he would lend me his long measure.
It is a long eighty-foot tape; he will know what I mean. I will
take care of it, for I want to take a more exact plan, though this
is pretty exact, I think. I have also been drawing a little. I
intend to take a view of _all_ (about five) the principal houses in
that great town, Hove. I have already taken one or two.
In the intervals of his classical studies he seems to have employed
himself, not only in making a survey of Hove in its existing state, but
also in a critical examination of the works in progress for its
enlargement. It is told of him that one evening he predicted the fall,
before the next morning, of some houses which were building opposite the
school, and laid a bet on the subject, which his companions readily
accepted. He had noticed the bad way in which the work was done, and
that the stormy weather, which appeared to be setting in for the night,
would probably blow the walls down. In the morning he claimed the
wager, for the buildings had fallen in the night.
Except from November 1820 to August 1822, when he was at the Collége
Henri Quatre at Paris,[3] Mr. Brunel was so very little absent from home
that he became thoroughly acquainted with all his father’s undertakings.
Among these was the veneering machinery at Battersea, remarkable for the
great diameter of the saw, the steadiness of its motion, and the
mechanical arrangements for clearing the veneer from the saw; also the
works at the Government establishments at Woolwich and Chatham, and the
machinery for making shoes. They have been fully described by Mr.
Beamish; but the mere mention of their names is enough to show how great
were the advantages enjoyed by Mr. Brunel in receiving from his father
his early professional education.
From the year 1823 Mr. Brunel was regularly employed in his father’s
office. It was in the early part of this year that the project of the
Thames Tunnel first began to occupy Sir Isambard’s attention; but he was
also engaged at that time in other works of great importance, among them
the suspension bridges for the Ile de Bourbon, and designs for bridges
of the same character over the Serpentine, and over the Thames at
Kingston.[4] Some account of the Bourbon bridges, and also of
experiments with carbonic acid gas, on which Mr. Brunel was engaged,
will be found in the notes to this chapter.
The history of the Thames Tunnel will be told, as far as possible, in
Sir Isambard Brunel’s own words, as given in his journals.[5] Although
these extracts do not relate to works for which Mr. Brunel was
personally responsible, they have been inserted in the belief that they
are valuable, not only as showing the nature and extent of his duties as
his father’s assistant, but also as displaying, in the most interesting
and authentic form, Sir Isambard’s character and genius at a time when
his son was brought into hourly contact with him, and under
circumstances which would cause the influence of his example to make a
deep and lasting impression.
Previously to the year 1823 there had been several plans suggested for
the construction of a tunnel under the Thames; and it would seem that a
great demand was supposed to exist for some such means of communication
between the two sides of the river eastward of London Bridge; for after
the failure of the operations undertaken by Mr. Vasie in 1805, and Mr.
Trevethick in 1807,[6] a high level suspension bridge was proposed,
although it was not intended to be used for heavy traffic.[7]
The first reference to the Tunnel in Sir Isambard’s journals is dated
February 12, 1823. ‘Engaged on drawings connected with Tunnel;’ and on
the 17th and following days of the same month, ‘Isambard was engaged on
Tunnel.’ These entries become more and more frequent in the pages of his
diary, until it is evident that Sir Isambard’s whole time and thoughts
were absorbed in this work.
The spring of 1823 was occupied in preparing drawings and models of his
plans, and in enlisting the sympathy and assistance of various
influential persons. By the close of the year the designs were matured
sufficiently to enable the promoters of the scheme to commence the task
of organising a company for carrying it out; and in January 1824 they
resolved to call a general meeting of their friends, and invite public
subscriptions.
On February 17, Sir Isambard explained his plans at the Institution of
Civil Engineers, and on the next day a meeting was held at the City of
London Tavern, under the presidency of Mr. William Smith, M.P., more
than a hundred persons being present. Resolutions authorising the
formation of a company were passed unanimously, and the share list was
opened. In the course of an hour one-third of the subscriptions was
filled up, namely, 1250 shares; and before the end of the day the number
of shares taken was 1381.
Borings were then commenced in order to ascertain the nature of the
strata through which the Tunnel would pass. A bed of gravel was found
over the clay, which gave Sir Isambard great anxiety. A large pipe or
shaft was sunk on the side of the river, and in it the water rose to
within three feet of the surface of the ground, and fell about eighteen
inches with the tide. ‘It is manifest (Sir Isambard writes) from this
that unless the Tunnel is enclosed in the stratum of clay, it would be
unsafe to drive through the bed of gravel. The Tunnel must, therefore,
begin with the substantial clay.’
However, the result of thirty-nine borings in two parallel lines across
the river, to the depth of from 23 to 37½ feet, seemed to prove that
there was below the gravel a stratum of strong blue clay of sufficient
depth to ensure the safety of the Tunnel.[8]
A report to this effect was made to the shareholders at their first
general meeting in July, and it was also stated that the works would be
completed in three years.
The first operation connected with the works, was the constriction of a
shaft; and for this purpose land was bought on the Rotherhithe bank,
about fifty yards from the river. On March 2, 1825, the ceremony of
laying the first stone of the shaft was performed.
Mr. Smith, our chairman, attended by most of the members of the
Court of Directors, and a very numerous cortége of friends invited
on the occasion, proceeded from the Tunnel Wharf to the ground,
where they were received among the cheers of a great concourse of
people. Mr. Smith addressed the assembly in a very eloquent speech
suitable to the occasion, and performed the ceremony of laying the
first stone. From this day dates the beginning of the work.[9]
The mode in which Sir Isambard decided to construct the shaft was one
not uncommonly adopted in the construction of wells; but to apply it to
sinking a shaft fifty feet in diameter was a novel and bold undertaking.
The brickwork intended to form the lining of the shaft was built on the
surface of the ground, and the earth being excavated from within and
underneath the structure, it sank gradually down to its final position.
The brickwork was 3 feet thick, bound together by iron and timber ties,
and there were built into it 48 perpendicular iron rods, one inch in
diameter, fastened to a wooden curb at the bottom, and to another curb
at the top of the wall, by nuts and screws.
When the shaft or tower of brickwork was completed up to the top, 42
feet in height, the next step was to remove the blockings on which it
rested, and this being done the gravel was excavated and hoisted up, and
the shaft descended by its own weight.
The Rotherhithe shaft was only sunk forty feet in this manner; the
remaining twenty feet, in order to leave the opening for the Tunnel, was
constructed by under-pinning, or underlaying, as it was then termed. The
underlaying was commenced in the beginning of June.[10]
By July 4 they had got down to the level of the intended foundation of
the shaft, having passed into a stratum of gravel, black pebbles
embedded in greenish sand, with little or no water; from which
circumstance Sir Isambard was of opinion that it was unconnected with
the stratum of gravel above.
_July 12._--Engaged on a general drawing for the great shield, and
in preparing some instructions for moving the same (a very
intricate operation!)
_July 22._--Underlaying is a very laborious mode of proceeding. The
sinking of a wall well bound as the first, would evidently be the
best and cheapest mode for making another tower of 50 feet
diameter.
On the 28th Sir Isambard enters in his journal the following additional
observations upon the success of his plans for sinking the shaft:--
Considering the great labour necessary for securing the ground for
the underlaying, the waste of planking, and of shores, and the time
necessarily taken up in moving about, in securing and in baling
out the water, and the many causes of interruption, and the
imperfect way that things are done in underlaying, it is quite
conclusive that the original plan of making a shaft, by sinking the
structure, is the safest and the most economical. What is done is
sound, and when once in place, may be secured with foundations in a
very easy manner. The brickwork of the shaft is remarkably hard.
Had it been made with brick facings and rubble stone, it would
certainly be water-tight, and almost impenetrable by ordinary ways.
The _vertical ties_ and the _circular wall bands_ are not to be
dispensed with in a structure destined to be moved as the present
has been.
On August 11 the underlaying was completed, and preparations were made
for constructing a reservoir in the bottom of the shaft for receiving
the permanent pumps. This was finished on October 11, with great
difficulty, owing to the nature of the ground, which consisted of loose
sand containing a large quantity of water.
_August 19._--Engaged at home in revising my plans for the manner
of carrying on the horizontal excavation, more particularly of
penetrating through the shaft. This part of the operation requires
_indeed_ very great attention, as it presents great difficulties,
arising from the wall to be broken through, and chiefly from the
angular opening that is to be made at each extremity. Then another
consideration is the uniting the brick arches to the brickwork of
the shaft.
_September 16._--Engaged in the early part of the day on revising
my plans of future operations in the Tunnel work, and in adapting
them to the nature of the ground as it is found at the various
depths we have penetrated: namely, to about 73 feet. Went
afterwards to Maudslay to request that the great shield may be
completed.
[Sidenote: Great shield.]
_October 14._--Engaged in the early part of the morning in making
some arrangements for the working of the great shield. Too much
attention cannot be given to that subject at the early part; for,
when once in its place, it would be extremely inconvenient to make
any alteration.
[Sidenote: Preparing for the frames.]
_October 15._--The dome of the reservoir will be covered to-day
about noon; the bottom of the shaft will therefore be completed.
They are now preparing to apply two frames of the shield. The
ground now open in the front is remarkably hard; it consists of
pebbles imbedded in a chalky substance, with hard loose stones of
the nature of the Kentish rag. Everything is going on well. Devised
with Isambard how to make our wells for the descent of the
materials, &c.
Thus at last the shaft was completed, and Sir Isambard was able to
commence the Tunnel itself, which he ultimately determined to construct
in the form of a rectangular mass of brickwork, 37½ feet wide and 22
feet high, pierced by two parallel horseshoe archways, each 14 feet wide
and 17 feet high.
Before entering upon the history of this undertaking, some account must
be given of the machine which Sir Isambard Brunel devised for effecting
its accomplishment.
In order to avoid a quicksand of considerable depth and extent, the
Tunnel had to be carried but a short distance below the bed of the
river; and, as in all tunnelling through soft soil,[11] the top and
sides of the excavation had to be supported until the brickwork was
built in; and the front or face had also to be held up as the miners
advanced. This support was given by means of a machine called ‘the
shield,’ described on one occasion by Sir Isambard as ‘an ambulating
cofferdam, travelling horizontally.’[12]
The main body of the shield consisted of twelve independent structures
or ‘frames’ made of cast and wrought iron. They were each 22 feet high,
and rather more than 3 feet wide; and, when placed side by side, like
books on a shelf, against the face of the excavation, they occupied the
whole area of the face, and also the top, bottom, and sides for 9 feet
in advance of the brickwork. Each frame stood on two feet resting on
the ground, and was divided in its height into three cells by cast-iron
floors. In these cells, of which there were thus thirty-six in all, the
miners stood, and worked at the ground in front of them.
The duty which the shield had to perform was to support the ground until
the brickwork was built within the excavation; but it was essential that
this should be done in such a manner as to allow of the mining
operations being carried on; and it was also necessary that the machine
itself should be capable of being moved forward.
The first point, therefore, which has to be explained in the action of
the shield is the manner in which the earth was supported by it.
It has been already stated that each frame rested upon two feet, or
large iron plates. These two feet together covered the ground under the
frame to which they belonged, and thus the whole of the earth beneath
the frames was pressed down by the feet.
The earth above was supported by narrow iron plates, called staves, laid
on the heads of the frames parallel to the line of the Tunnel, the ends
resting on the completed brickwork behind it. The earth at the sides was
kept up by staves resting against the outermost frames.
The arrangement for holding up the earth at the face of the excavation
was necessarily of a more complicated character. Each frame supported a
series of boards called poling-boards, by means of small screw-jacks or
poling-screws, two to each poling-board, which abutted against the
frames, and pressed the boards against the earth. The boards were 3 feet
long, 6 inches wide, and 3 inches thick, and were arranged horizontally.
These poling-boards, more than five hundred in number, covered the whole
surface in front of the frames.
To resist the backward thrust of the poling-screws against the frames,
each frame was held forward by two large screws, one at the top of the
frame, and the other at the bottom, abutting against the brickwork of
the Tunnel. The brickwork was completed close up behind the shield as it
advanced.
The way in which the earth was excavated, and the shield moved forward,
has now to be explained.
The plates or staves which supported the ground at the top and sides of
the shield were pushed forward separately by screw-jacks; but in order
to advance the poling-boards in front, it was necessary that that
portion of the ground against which they pressed should be removed.
The miner, standing in his cell, took down one, or, at the most, two of
the poling-boards, commencing at the top of the cell, and having
excavated the earth a few inches in advance, replaced the poling-boards
against the newly-formed face, pressing them against it with the
poling-screws. Thus the excavation was carried on without depriving the
ground of the support it received from the shield, except at the point
where the miner was actually at work.
The operation of advancing the frames was effected in the following way.
When everything was ready for a move, one of the feet which carried the
frames on jointed legs was lifted up, and advanced forward a few inches,
and then pressed down on to the ground, until in its new position it
again bore the weight of the frame. This done, the other foot was
lifted, moved forward, and screwed down in the same manner, and then the
frame itself was pushed ahead by means of the large abutting screws,
which kept it top and bottom from being forced back on the brickwork.
It is, however, evident that these abutting screws would have been
unable to push on the frame, while the ground in front was pressing back
the poling-boards against it; therefore, during the process of moving a
frame, it had to be relieved from the thrust of its poling-screws.
Accordingly, when it was desired to advance any one of the frames, the
butts of the poling-screws of the tier of boards in front of it were
shifted sideways, so as to rest, not against the frame to which they
belonged, but against the frames next it on either side. This done, the
frame itself was advanced, and was then ready to receive again its own
poling-screws, and also those belonging to the adjoining frames, so that
they might in their turn be moved forward. It will thus be seen that the
whole shield was not moved forward at one time, but that the frames were
advanced alternately.
There were many other ingenious arrangements in the design of the
shield, which need not be referred to in a description intended only to
give such a general idea of the machine as may make the history of its
operation intelligible.[13]
When the frames had been completed in Messrs. Maudslay’s factory, they
were conveyed to Rotherhithe, and lowered down the shaft. An opening had
been left at the bottom of the wall, about 37 feet wide by 22 feet high,
and against this the shield was erected. It was then ready to commence
its progress through the ground below the river.
On November 25, 1825, the shield made its first start. Sir Isambard was
unfortunately unable to witness what was in fact the actual commencement
of the Tunnel, as he had three days before been seized with a sudden and
alarming attack of illness, which kept him at home till December 6. The
works were left under the direction of Mr. Brunel.
_December 8._--The great shield is advancing very slowly, meeting
with much interruption by the water, which still runs within the
cells, and also by the difficulty of forming abutments for the
frames. [_Temporary abutments were necessary until the shield was
sufficiently advanced to allow of its being pushed forwards from
the brickwork built up behind it._]
_December 29._--The frames are very much out of level in the
transverse line of the Tunnel. This would be attended with serious
inconvenience if I had not provided for the means of recovering any
irregularity that might take place, and which, as it appears,
cannot perhaps be prevented; but having foreseen this, I have
provided the remedy by being able to take down the top of each
frame, and to remove the top staves in parts, or the whole, at
pleasure--a very important provision it proves to be.
_January 16, 1826._--Too much precaution cannot be taken, in the
management of the frames, to have the leg-screw particularly well
secured, as every foot-run of the arch of the Tunnel sustains 82
tons. Each frame carries as follows:--
The two end frames each 65 tons = 130
Ten others, each 52½ " = 525
---
655 tons.
_January 21._--The ground at the top and sides very good; same in
the front. In breaking the ground out of the limits of the shield
on the right a great deal of ground fell in. This indicates that,
if it was not for the protection of the shield, nothing could be
done. This accounts also for the occasional breaking of the ground
in making the drift in 1809.
[Sidenote: Tunnel begun.]
The brickwork of the entrance being carried as far as directed, the
body of the Tunnel was begun to-day.
[Sidenote: Water broke into the works.]
_January 26._--Isambard went down to Rotherhithe; the water had
broken in in great abundance upon the work over Nos. 4 and 5. [_The
twelve frames were distinguished by numbers._] A 4-inch pipe was
driven over the shield from inside the shaft, but the water did not
follow it, and the stream augmented very rapidly. The frame No. 5
was moved forward, and it checked the water for a moment, but it
came again with violence. A heading was immediately ordered by
Armstrong [_the resident engineer_] from the east well, in which
Isambard concurred.
_February 3_.--Ordered a pit to be opened and made by sinking a curb 8
feet diameter and 18 inches thick, well bound with bolts. [_This pit was
a well sunk from the surface to enable the gravel containing water, into
which the head of the shield had penetrated, to be removed, and clay
substituted_.]
_February 6_.--The shaft begun last night, and was sunk 20 feet to-day,
and remarkably true. Had we known the ground as we now know it, we
might, by having opened a well contiguous to the great shaft, have sunk
the shaft in a week; but for that purpose we must have had two steam
engines, one for pumping the water, and the other for taking up the
ground.
[Sidenote: Unremitted attention wanted.]
_February 10_.--Went very early to the Tunnel for the purpose of giving
directions to prop up the back of the staves, which, for want of weight
at the new shaft, might be overbalanced by the pressure of the ground at
the back. I could not rest a moment until it was done, for the
consequences might have been fatal, at this moment in particular. What
incessant attention and anxiety! To be at the mercy of ignorance and
carelessness! No work like this.
[Sidenote: Observations on the mode adopted to check the water.]
_February 12_.--The ground having been opened carefully from under the
curb of the pit [_see above on date February 3_], the greater part of
the gravel was removed, and stiff clay substituted for it. This was done
by driving first some wrought-iron flat bars, which kept the ground up.
This shows that the shield is a most powerful protection, and would
enable us to penetrate through a bed of gravel. Though the breaking in
of the water had somewhat terrified the man in No. 5, he soon returned
to his post, and the others have acknowledged their full confidence in
the security afforded by the shield. The boring ahead had not yet been
attended to: it is owing to the want of this precaution that this
accident is chiefly to be ascribed; for had we known as much as we now
do, we might have passed through without the pit being opened.
_March 1_.--Water at the back of the frames, but less than before. The
men show a great deal of spirit in overcoming the present difficulties.
Isambard was very busy yesterday and to-day in the frames, and about the
works. He was severely hurt in the leg by a piece of timber falling
against it. [_This accident prevented his attending again at the Tunnel
until the 24th_.]
On March 6 the proprietors paid a visit to the Tunnel, and were highly
satisfied with what they saw. On that evening Sir Isambard writes:--
It is of absolute necessity _now_ to provide for everything that is
conducive to the more expeditious management of the frames, and to
a greater facility in getting up the brickwork. If these two points
are realized, then indeed we may soon expect to be moving at a good
rate--not less than I have held out, namely, 3 feet per 24 hours.
[Sidenote: Water stopped as expected.]
_March 11._--Received early in the morning a report from Armstrong
stating that the water was completely stopped--that it had been
stopped during the night. Aware that we had passed the gravel, it
was of course expected that we were under the clay; means were
therefore resorted to, to drive clay and oakum at the tail of the
top staves, which was productive of a very good effect. The great
shield was soon entirely free of water. This shows the efficiency
of the shield to oppose difficulties which could not have been
overcome without the complete protection it affords, under almost
any circumstances. Indeed this has been a tedious operation since
January 25, when the water first burst upon No. 5, at the front of
the shield. The miners as well as the bricklayers have worked with
great spirit and perseverance through the whole, during a period of
44 days. The well that was made at the front of the shaft has been
of use in acquainting us with the extent of the open ground we had
to pass through. It will be made a useful opening for ventilating
the works. By means of this well we have been able to apply the
lead pipes with which the water has been diverted: it is not
therefore a useless expense. Things were put in better order to
prepare for a more expeditious way of working. Directions were
given to place the frames in a better condition. Isambard is still
too unwell to go to the Tunnel.
[Sidenote: Considerable slip of ground: how to check it.]
[Sidenote: Very dangerous.]
_March 25._--Went to the Tunnel with Isambard. Found that a
considerable fall of ground had taken place again at the right
side. No one could account satisfactorily for it. I inspected it,
and directed that, after making it good, flat bars of iron be
driven at the head of the side staves, in order to pin it up, and
in order to enable the miners to get at the solid ground. It is
very bad and extremely dangerous; the ground is evidently the same
as that which, in the report of the first attempt, was found so
loose as to have dropped upon the works, leaving a large cavity
above, when it is said the man ascended and made good the hole. We
should be warned by this, lest we should meet another as fatal as
it ultimately was on that occasion. [_This observation refers to
the driftway of 1807._]
_April 24._--By Armstrong’s report the water is entirely out, and
the men at work in the morning in removing the dirt, &c. Isambard
engaged at the Tunnel, where I am not yet able to attend as often
as I could wish. Everything goes on well, much through his
exertions.
_May 11._--One hundred feet will be completed to-night.
_May 22._--The top plate over the frame No. 1 has been cracked
without any particular violence or stress. It appears that it is
nothing but the change of temperature that is the cause of that
rupture. The accident justifies the opinion I have of cast-iron not
being safe upon traction, and the precaution of having had
wrought-iron bolts at the back of the frames. [_These were vertical
rods which took the tensional strain._] Without these bolts what
would have become of the shield, if one casting was to break? The
fracture was accompanied with a loud report like that of a gun.
Isambard was in the works at the time of breaking: nothing could
have prevented it.
[Sidenote: The shield being too much out, resolved to move it
bodily.]
_May 25._--I observed that nothing whatever had been gained to
recover the deviation [_the shield had gradually worked 2 feet 3
inches to the westward_], which subjects us to so much
inconvenience and loss of time. The only way to bring the shield
right is by taking the frames sideways.
_June 3._--Finding it too laborious and almost fruitless to bring
the frames in the right way, I came to the determination of having
them brought bodily to the east by cutting the ground on the side.
I accordingly gave directions to Armstrong to proceed in making a
heading out of No. 12, and by securing the side staves to continue
downwards until the ground be clear. The working was accordingly
discontinued in front.
_June 4._--The mode of proceeding by the common way of mining shows
the impracticability of carrying a large excavation anywhere,
particularly under a considerable body of water. The expense of
timbering would be too great, even if it could be sound. The ground
above the frames is remarkably good, but under it there is a
stratum of silt which breaks and falls in large masses.
[Sidenote: Isambard’s service very important and most efficient.]
_June 5._--Isambard got into the drift, and gave the line for the
better disposition of the staves, which was afterwards done in a
proper manner. Isambard’s vigilance and constant attendance were of
great benefit. He is in every respect a most useful coadjutor in
this undertaking.
_June 10._--The last frame (No. 1) is brought close to the others,
and the brickwork brought up to fill the back.
[Sidenote: Dangerous state of the ground. Precautions taken.]
_June 15._--On inspecting the face of the ground this morning I
observed a breach in the front of Nos. 3, 4, and 5, where the
ground has given way in the lower cell. This was truly alarming. I
ordered iron staves to each floor in order to pin the ground, and
thereby to counteract the slipping which would immediately take
place.
_June 19._--The bricklayers left off work, but, on enquiring into
the cause, I learned there was no other but to have a libation upon
the new arrangement of piece-work.
_June 29._--Gave positive directions to cut only 4½ to 5 inches
thick at a time at the front of the top cells, instead of 9 inches,
as they had done for some time.
_July 3._--The great question is, does the clay undulate at its
surface? We should have some reason to apprehend that it does so,
because at the beginning we had not proceeded many feet into the
clay when we struck again into the gravelly stratum. The surface of
the clay must therefore have sunk at that particular spot; which
circumstance seems to warn one of the need of great vigilance and
great prudence in the progress of the enterprise.
[Sidenote: Cofferdam burst at Woolwich.]
[Sidenote: Warning for us.]
_July 10._--A cofferdam burst yesterday at the works at Woolwich,
having blown up from the foundation. How cautious this should make
our men! The cofferdam may be repaired, and very easily too, but an
irruption into the Tunnel--what a difference, particularly at this
early period!
[Sidenote: Carelessness of the miners.]
_August 10._--Found the lowest cell of No. 1 left by the workmen
_without a single poling against the ground_. This is indeed a most
unjustifiable neglect.
_August 12._--At six this morning completed 205 feet.
[Sidenote: Observations on the bad effect and consequence of
driving on as is done.]
_August 21._--This piece-work has not been productive of much
effect as to quantity of work. As to quality it is very
questionable. A work of this nature should not be hurried in this
manner. Fewer hands, enough to produce 9 feet per week, would be
far better than the mode now pursued _from necessity_, but not from
inclination on my part. Great risks are in our way, and we increase
them by the manner the excavation is carried on. The frames are in
a very bad condition.
_September 5._--It is much to be regretted that such a work as the
Tunnel should be carried on by the piece. Obliged to drive on, no
time is left to make any repair, or to recover any lost advantage.
Isambard is most active. Mr. Beamish shows much judgment in his
exertions, and zeal in his attendance.[14]
[Sidenote: Water breaking in at back of frames.]
[Sidenote: How to check it. Isambard’s exertions.]
_September 8._--About 2 P.M. I was informed by Munday that water
was running down over No. 9. I went immediately to it. The ground
being open, and consequently unsupported, it soon became soft, and
settled on the back of the staves, moving down in a stream of
diluted silt, which is the most dangerous substance we have to
contend with. Some oakum was forced through the joints of the
staves, and the water was partly checked. Isambard was the whole
night, till three, in the frames. At three I relieved him. He went
to rest for about a couple of hours; I took some rest on the stage.
[Sidenote: Things improving.]
_September 9._--Towards noon the stream changed its character. The
clay, being loosened by the water, began to run, but it thickened
gradually. It was late in the evening before the loosened clay
acquired the consistency of a loose puddling, which covered the
staves, and made them a complete shield against further irruption,
or rather, oozings of mud. If we consider that at this place we
have at the utmost 9 feet between the top staves and the gravel,
over which the river flows, it is most satisfactory and most
encouraging to have this additional proof of the protection which
the shield affords. At nine o’clock at night Isambard sent me word
that ‘tout va à merveille;’ indeed it was so, for it was like a
stopper interposed between the river and the top-staves. Instructed
as the men were by the first accident, they went on as usual in the
irrespective occupations. Pascoe, junr., and Collins were
remarkably active and persevering, and some other men equally so;
while old Greenwell encouraged them by a speech of his own in high
commendation of the security of their situation.
[Sidenote: Water more abundant. Is it from the river?]
_September 12._--The water, bringing with it a sort of clay broken
in small particles, increased to an alarming degree. In consequence
of this continued displacement of the silt and clay, a cavity had
been formed above the staves. At about three, when I had gone to
the Court of Directors, the ground fell upon the staves with great
violence, causing a surge most alarming as to probable
consequences. Isambard was at that moment in the upper frames, and
he gave directions for increasing the means of security. On my
return I found things much worse than I left them, but every means
of security was judiciously applied. During the night in
particular things presented a very unfavourable appearance. The
men, however, were as calm as if there were no other danger to be
dreaded than wet clothes or the splashing of mud. I observed the
men in the lower cells were _sound asleep_.
[Sidenote: Exertions by the men.]
[Sidenote: Slight improvement.]
_September 13._--Every means were resorted to in the course of the
night and during the early part of the day to stop the water. The
men have shown great zeal and good management in their respective
avocations, and above all the utmost confidence. Isambard has not
quitted the frames but to lay down now and then on the stage. I
have prevailed on him to go to his bed, or rather, used my
endeavours to induce him; but he has not since last Friday night
(the 8th). Things were rather better at the close of the day.
_September 14._--Things upon the whole have assumed a more
favourable aspect. The situation is nevertheless very critical.
Nothing but the utmost precaution in following up what has begun
can bring us out of it. This has been a most eventful week!
_September 18._--Isambard was the greater part of the night in the
works, and the benefit of his exertions is indeed most highly felt:
no one has stood out like him! Everything is quite safe, the water
is kept back, and the work proceeds in a most satisfactory manner.
_October 22._--It is evident [_from a flow of silt which had taken
place on that day_] that with the shield we have passed close under
a body of collected water a few inches only above the staves.
Isambard is too unwell to stay long in the works.
[Sidenote: The want of a drain subjects us to much inconvenience.]
_October 24._--The want of the main drain which was originally
intended to carry the water to the main reservoir is felt
everywhere. This drain is in my original plan, but the committee
expressing on several occasions a wish that I should dispense with
it, I complied, most reluctantly however, to prove my earnest wish
to reduce the expenses. It will not, I apprehend, be found an
economy.
[Sidenote: Effect of the shoes in keeping the ground dense.]
_October 26._--Every step we take shows how much security is
derived from the shoes, supporting as they do the shield and the
superincumbent weight. They press down in the same proportion the
ground on which they bear. They keep it as dense as it originally
was, and fit it for the structure that is to come upon it. It is
evident, therefore, that what is wanted is that the ground should
be kept pressed. It is with this object in view that I have
holdfasts and jacks. What incessant vigilance is required, what an
incessant call on the resources of the mind, not only to direct,
but more particularly to provide for many things that may occur.
_November 17._--At this date 307 feet 9 inches had been
completed.[15]
_December 8._--The evil [_that of not having a proper drain_] is
going on with us, and without any remedy except the drain, or a
cesspool by way of expedient. How much anxiety must one feel at
being so circumstanced! Should any water break in, how should we
proceed? This is another source of great solicitude. We have no
command of the frames when they rest upon wooden legs, or when the
screws are bent; and what is worse is that the men drive on without
any consideration or any fear of consequences. This circumstance,
and the apprehension of the water breaking in, are matters of the
most dreadful anxiety.
[Sidenote: Superincumbent weight varying daily, and still more
every fortnight. What stress on the frames. The shoes have never
yielded; a most important circumstance.]
_December 12._--Little do others know of the anxiety and fatigue I
have to undergo day and night. Advanced as we are, we have only
gained somewhat more experience, but the casualties are just the
same. An accident now might be as fatal as it would have been 200
feet back, or as it would be 200 feet forwards. We have not a
period when we can think ourselves safe except when we have
connected these arches with a shaft on the other side. Loaded as we
are with the weight of the river, we have to advance our shield and
build our structure under that weight, a weight which varies twice
a day, and twice a month to a much greater extent. _The shoes are
the great foundation of our security._ When once pressed down with
the greatest power that can be applied, they do not give in the
least afterwards. They have not yielded even upon loose gravel; we
must therefore congratulate ourselves that they have answered so
completely. We have now walked our frames upwards of 350 feet; we
have had to renew the legs and the heads, but it is not through
want of strength so much as from mismanagement. The first legs were
never injured so long as their action was limited to 3 inches, but
when it was increased to 6 inches, they immediately gave way one
after another, without however any damage to the structure or to
the shield. The heads gave way, or began to give way, from the
moment the legs did; because, when a leg gave way, it brought upon
the contiguous frame an increased weight which broke the heads one
after another. That the breaking of so important a part of our
shield should not have been attended with any bad consequences is a
proof that provision had been made for the casualty. The proof that
it had been foreseen and provided for is in the manner these heads
were adapted to the frames. By the way they were fixed they would
be easily taken down and replaced. Though the heads gave way, the
top staves were not materially affected by it, and the service
continued until new heads were substituted. Some have fancied that
the ground did not bear wholly upon the shield and the arches, but
supported itself in parts. Experience proves that the pressure is
rather more than that which rests artificially on the frames. The
ground is compressed all round by the increased weight of high
water: we might therefore conclude that the shield operates as a
pillar, that supports beyond the limits of its base or cap. It is a
great satisfaction to be able to say that so long as we followed
the original plan, nothing gave way except the back screws. These
again were damaged by being run out of the sockets. We may
therefore ascribe most of the evils and damages to the increased
range of action, and still more to the rude implements the men have
used, whenever they met with any difficulty in moving the frames.
If it is considered that we had no other men to train in the use of
this immense machine but excavators and miners, very great
allowance must be made for what has occurred.
[Sidenote: Falling of three facings from neglect. Awful!]
_December 20._--An accident of an alarming nature occurred. The
poling-screws of Nos. 10 and 12, being on No. 11, Moul, the miner
in that frame, removed his butting screw; the consequence was that
the frame started back, the polings and poling-screws fell down
with a tremendous crash, and the ground followed to a considerable
extent. This is the most formidable accident that has yet occurred
in the face of the work. The ground was fortunately unusually firm,
and no fatal consequences ensued.
_December 31._--Isambard and nine friends sat down to a dinner
_under the Thames!_ Now a year is over since we began to make any
progress horizontally, for we had only 11 feet of arch when the
water broke in on January 24 last. We may therefore say that the
whole of what has been made of the Tunnel has been made in that
period. It is worthy of remark that until the end of April no
fracture whatever, no bending of the legs, had taken place,
notwithstanding that we had supported for a period of nearly three
months a greater weight than we ever had since. The ground nearly
40 feet high _kept sinking upon us_ as we advanced, and yet no
stave, no top, no leg gave way. Each leg was capable of carrying
nearly 80 tons at the point of fracture, consequently the aggregate
strength of 36 legs was equal to 2,880 tons, which is six times
over the greatest effort that could be exerted by the
superincumbent weight. The heads, after they had given way,
remained in place, some--namely, Nos. 1, 8, 12--for seven months,
and the others from four to six months. It cannot be said therefore
that there was a want of strength, since the broken heads continued
to perform for so many months after being so much damaged; nor is
there any defect in the iron. If the frames were, as some have
fancied, lanky, which implies weakness in their sides, how could
they have supported the alternate stress to which they are put by
standing alternately on one leg? Not one single joint has yet
started. Every frame has been upwards of 2,000 times in that raking
posture, consequently the shield has been upwards of 24,000 times
strained under the weight that has broken the heads. One single
side has broken, and is now as good as the rest. Is such a machine
to be stigmatised as it has been, without looking more minutely
into its operations?
[Sidenote: Observations on the responsibility attached to this
enterprise.]
_January 4, 1827._[16]--A work that requires such close attention,
so much ingenuity, and carried on day and night by the rudest hands
possible--what anxiety, what fatigue, both of mind and body! Every
morning I say, Another day of danger over!
_January 12._--It is astonishing how the silt resists the sliding
of the top staves. Assured as we were of having stiff clay from 33
to 37 feet, with what confidence we might have looked to making 18
feet per week. There would be no difficulty in having accomplished
it. We must not look back, but overcome all difficulties!
[Sidenote: Isambard on duty several successive nights.]
_January 16._--Isambard having been up several successive nights,
went to bed at ten, and slept till six the next morning. I am very
much concerned at his being so unmindful of his health. He may pay
dear for it.
_February 2._--Work done to this day 405 feet 4 inches.
_February 3._--I visited the works; and, being in the cabin, I
complained of the dust there. _Dust under the Thames!_
_February 26._--I went to the Tunnel. The arch being well lighted
up, and the whole walk completed, a few visitors were admitted. The
coup d’œil was splendid. Mrs. Brunel, Emma, Sophia and her three
little children were the first. It gave me great pleasure to see
the whole of my family in the new scene.
_March 21_.--There being no clay above us, there is much to
apprehend from the springs. It would be much better to work slower
than we do. It is indeed very hard to be under the necessity of
driving. Anxiety increasing daily.
[Sidenote: No clay above head; should work slower.]
[Sidenote: Water increasing daily.]
_March 28_.--The top pumps failed; the water rose above the
abutting screws. The frames of some of them could not be advanced,
nor could the bottom brickwork be laid down--great source of
complaint. Isambard called the men in at 10 o’clock; they went on
cheerfully. It is surprising that the men are so steady.
[Sidenote: Our situation is getting much worse daily.]
_March 29_.--Things are getting worse every day by the influx of
water; by which the ground is softened, and the operation rendered
extremely complicated and slow. As to the ground, it is evident we
are now as Isambard found it by his borings of August last. We have
nothing above our heads but clayey silt, and it is of a nature to
be detached and run into mud by the action of water.
_April 3_.--The pumping now requires forty hands. There is no
exaggeration in saying that the influx of water, and the badness of
the ground, cause an extra expense of 150_l_. a week.
[Sidenote: Obstacles in every way.]
_April 7_.--It may now be said that we are contending with the
elements above and around, gaining and disputing every inch that we
add to the structure.
_April 9_.--Isambard’s birthday, he being of age to-day.
_April 14_.--Doing as well as can be expected from the nature of
the ground, and the difficulties that increase upon us.
[Sidenote: To be obliged to drive too fast is a sad alternative.]
_April 18_.--The faces are found extremely tender; but having
proceeded with great caution, no accident occurred. None, I feel
confident, would occur if all idea of piece-work were abandoned. It
always operates as a stimulant, a very dangerous one. Obliged to
drive on, on account of expense, we run imminent risks indeed for
it. That a work of this nature, under such circumstances, should be
thus carried on, is truly lamentable. It is obvious that the clay
we have above our heads has been broken, by the ground beneath it
running or breaking in upon us. We shall have to fight it out until
we have a stronger or thicker stratum of clay. Sad prospect indeed
it is for us!
_April 20_.--The ground at No. 1 broke in again, and occasioned
great delay. Some bones and china came down.
_April 22_.--The diving-bell being on the spot, and Isambard having
moored it over the shield, he and Gravatt[17] descended at thirty
feet water. They found the same substances which had come through
the ground into the Tunnel. When Isambard was in the bell, he drove
a strong rod into the ground. Nelson, who was in the frame, heard
the blows.
[Sidenote: A dreadful panic.]
_April 29_.--Ground improving as we advance; we are not, however,
free from danger: a dreadful alarm took place this morning. While
Isambard and Gravatt were at breakfast, the porter came running in,
and exclaiming, ‘It is all over! The Tunnel has fallen in, and one
man only has escaped.’ Gravatt was the first to get to the spot,
and found all the pumpers upon the floor of the shaft, all
stupefied with horror, though every one was there quite safe, and
no rush of water was heard. Gravatt and Isambard were soon in the
shield, where they observed that a small portion of clay had fallen
from the top on the top floor.
_May 8_.--At half-past three in the morning, an irruption took
place, bringing down the deposits of the bottom of the river--lumps
of clay, stones, bones, wood, nails, &c., &c., with water. The
pumpers and men on the stage (Irish) all ran away, some exclaiming,
‘The Thames is in! The Thames is in!’ Ball and Rogers stood to
their post, and soon stopped this most formidable attack.
_May 10_.--Great difficulties present themselves, that oppose our
progress; the chief, however, is the lodgment of water above our
heads. There it loosens the silt or sand, and runs out, leaving
cavities that cause the clay above to break, and run down in lumps
and disturbed streams. This is very awful! This opens the way for
the river.
[Sidenote: Consequences of want of care more terrific and
mischievous than any preceding ones.]
_May 12_.--In moving No. 6, they left by some unaccountable neglect
the top staves behind, and in that state two top polings were taken
down. The ground being very bad, and high water at the same moment,
the ground began swelling. Attention was called to several points,
and Gravatt continued in No. 6. He drew out at the front of the top
staves a shovel, and also a hammer, that had come through the
ground above. They are the same which Isambard left at the bottom
of the river, when he went down in the diving-bell.
[Sidenote: Triumph of the shield.]
_May 13_.--Notwithstanding every prudence on our part, a disaster
may still occur. _May it not be when the arch is full of visitors!_
It is too awful to think of it. I have done my part by recommending
to the directors to shut the Tunnel. My solicitude is not lessened
for that: I have indeed no rest, and I may say have had none for
many weeks. So far the shield has triumphed over immense obstacles,
_and it will carry the Tunnel through_. During the preceding night
the whole of the ground over our heads must have been in movement,
and that too at high water. The shield must have therefore
supported upwards of _six hundred tons_: it has walked for many
weeks with that weight twice a day over its head. What flippancy
and inconsistency in some individuals, who, without any knowledge
of the subject, without so much as examining the state of the work,
will without the least reflection and hesitation obtrude their
suggestions upon every case. What shallow conceit for such to
pretend they can know better than those that have already the
experience that must result from years of deep thought, from days
and nights of incessant attention; who have the advantage of the
combined talents of several ingenious men, who devote their
undivided study, the whole resource of their well-stored minds, to
the enterprise; and to add to this, the benefit of the skill of one
hundred miners and excavators. Among this class of men, some have
been employed in the most perilous enterprises, when each
individual must have acted upon his sole judgment, where, in fact,
there is no room for an engineer to instruct and direct their
efforts. How easy it is to attack everything, to detract from the
merits of the best plan. There is always some weak point which may
be open to the penetration of the shallowest mind. Then comes the
exulting expression, _That I always said would never do, &c.,_ and
all the consequences with it.
[Sidenote: How easy to detract.]
_May 15_.--The water increased very much at 9 o’clock. This is
_inquiétant_! My apprehensions are not groundless. I apprehend
nothing, however, as to the safety of the men, but first the
visitors, and next a total invasion by the river. We must be
prepared for the worst. I have had no rest for many weeks on this
apprehension. Should it occur we must make the best of it, by
improving our situation.
_May 17_.--There is no doubt of the ground having improved very
materially since last Saturday. Very cheering indeed.
_May 18_.--Visited by Lady Raffles and a numerous party. Having had
an intimation by Mr. Beamish of their intended visit, I waited to
receive and to accompany them, not only from the interest I felt at
being acquainted with Lady Raffles, but also from motives of
solicitude, knowing that she intended to visit the frames. Indeed,
my apprehensions were increasing daily. I had given some
instructions for enquiring where we could obtain clay, that we
should have some barges full of clay to be in readiness. I was most
anxiously waiting for the removal of the tier of colliers that was
over us, being convinced that we should detect some derangement
then. I attended Lady Raffles and party to the frames, most uneasy
all the while, as if I had a presentiment, not so much of the
approaching catastrophe to the extent it has occurred, but of what
might result from the misbehaviour of some of the men, as was the
case when the Irish labourers ran away from the pumps and the
stage. I left the works at half-past five, leaving everything
comparatively well: Mr. Beamish continued on duty.[18]
Mr. Gravatt’s account is as follows: I was above with I. Brunel
looking over some prints, Beamish being on duty. Some men came
running up and said to Isambard something I did not hear. He
immediately ran towards the works, and down the men’s staircase. I
ran towards it, but could not get down. I leaped over the fence,
and rushed down the visitors’ stairs, and met the men coming up,
and a lady, who I think was fainting. Met Flyn on the
landing-place, who said it was all over. I pushed on, calling him a
coward, and got down as far as the visitors’ barrier. Saw Mr
Beamish pulled from it. He came on towards the shaft walking. I
went up to him to ask him what was the matter. He said it was no
use resisting. The miners were all upon the staircase; Brunel and I
called to them to come back. Lane[19] was upon the stairs, and he
said it was of no use to call the men back. We stayed some time
below on the stairs, looking where the water was coming in most
magnificently. We could still see the farthest light in the west
arch. The water came upon us so slowly that I walked backwards
speaking to Brunel several times. Presently I saw the water pouring
in from the east to the west arch through the cross arches. I then
ran and got up the stairs with Brunel and Beamish, who were then
five or six steps up. It was then we heard a tremendous burst. The
cabin had burst, and all the lights went out at once. There was a
noise at the staircase, and presently the water carried away the
lower flight of stairs. Brunel looked towards the men, who were
lining the staircase and galleries of the shaft, gazing at the
spectacle, and said, ‘Carry on, carry on, as fast as you can!’ Upon
which they ascended pretty fast. I went up to the top and saw the
shaft filling. I looked about and saw a man in the water like a
rat. He got hold of a bar, but I afterwards saw he was quite spent.
I was looking about how to get down, when I saw Brunel descending
by a rope to his assistance. I got hold of one of the iron ties,
and slid down into the water hand over hand with a small rope, and
tried to make it fast round his middle, whilst Brunel was doing the
same. Having done it he called out, ‘Haul up.’ The man was hauled
up. I swam about to see where to land. The shaft was full of casks.
Brunel had been swimming too.
The first alarm, as I heard it, was as follows: Goodwin, in No. 11,
said to Roger, in the next box, ‘Roger, come, help me.’ Roger said,
‘I can’t, I have my second poling down, and my face will run in.’
In a little time Goodwin said, ‘You must come,’ which Mr. Beamish
directed him to do. Roger turned round and saw Goodwin through a
sheet of water. Corps, a bricklayer, went to help Goodwin: he was
knocked down. Roger made his way alone, calling to Mr. Beamish,
‘Come away, sir, ‘tis no use to stay.’ Roger saw Corps fairly
washed out of his box like a lump of clay.
Sir Isambard’s journal continues:--
_May 19._--Relieved as I have found myself, though by a terrible
catastrophe, of the worst state of anxiety, that which I have been
in for several weeks past, I had a most comfortable night. Isambard
and Gravatt descended with the diving-bell, and stood upon the
tails of Nos. 10, 11, and 12.
_May 20._--Having descended into the hole and probed the ground, I
felt that the staves were in their places, and that the brickwork
was quite sound. It is evident that the great hole has been a
dredging spot. A large mass of bags full of clay, and united
together with ropes, was let down. The Rotherhithe curate, in his
sermon to-day, adverting to the accident, said it was a fatal
accident, that it was but a just judgment upon the presumptuous
aspirations of mortal men, &c.! The poor man!
_May 23._--Went with the diving-bell to examine the ground and the
bags, which do apparently well, but it is working rather in the
dark. It cannot, however, fail of making a much better stratum than
that we had before. The plan is therefore good.
On the 30th a raft was sunk over the shield, and the water in the shaft
was brought so low that the last flight of steps was visible. However,
on the next day the river broke in again; and as it was found that the
raft was open at the west side, it was raised and towed on shore.
_June 5._--There is much danger in getting out of the diving-bell,
the bags are so loose in some places. One might sink and be
swallowed, which had very nearly happened to-day. Isambard and
Pinckney being down, the latter lost his hold. The footboard being
accidentally carried away, he could not have recovered himself had
not Isambard stretched out his leg to his assistance.
_June 17._--Visited by Charles Bonaparte. Isambard took him into
the arch with the yawl. Isambard fell overboard.[20]
On June 19, a general meeting of the proprietors was held, to consider
the position of the company. Sir Isambard addressed the meeting, and
also presented a long report, in which he entered very fully into the
circumstances of the recent accident and the causes which led to it. He
then described the means he had taken to restore the works by sinking
bags of clay and gravel. He adds: ‘I have already succeeded in closing
the hole through which the water first penetrated, and feel confident
that the second opening which afterwards appeared is also stopped, but a
short time is necessary to elapse for the new ground over the shield to
settle and consolidate. It has already supported a head of water of
thirty-five feet.’
_June 25._--At 7 P.M. made preparations to re-enter the shield.
Isambard, mustering the men who had been the last to quit the
frames, told them they would be the first to take possession of
them again--a precedence due, as he said, to them. Rogers, Ball,
Goodwin, Corps, and Compton, were accordingly ordered to trim
themselves for the expedition, provided with a phosphorus box, and
dressed in light clothes, to be fit for a swim.
At about ten o’clock, Isambard and Mr. Beamish, accompanied by Ball
and Woodward (miners), went down with the punt, and got to the
large stage, the head of the crane just emerging. It was found
impossible to get into the frames, as a mound of clay and silt
closed the entrance. The centering was in place and quite sound,
and of course the brickwork. Finding that they could not get
nearer, they gave three cheers, which were rapturously answered by
the men at the mouth of the Tunnel. Having placed candles upon the
ground that closed the entrance, and upon the head of the crane,
they returned. Isambard, having promised that the men who had left
the frames last should be the first to re-enter, returned with
them. This is a great day for our history!
_June 27._--Mr. Beamish was able to get to the frames, which he
found firm and undisturbed.
A small tarpaulin was now spread over the frames, and operations
commenced for cleaning them. This was a most difficult and dangerous
work, especially as the water was still so high that the frames could
only be approached by boats. The men, even the best hands, were at first
greatly alarmed at the danger they were in; but the example set by Mr.
Brunel and Mr. Beamish produced, as Sir Isambard notes, the best effect,
and they soon became reconciled to their situation.
_July 7._--Very uncomfortable in the frames; the candles cannot
burn, the ventilation cannot act. Isambard went several times
to-day down in the diving-bell. On one occasion the chain slipped
through the stoppers, but most providentially it jammed itself
tight before being altogether run out. _The consequence might
indeed have been fatal._ Can there be a more anxious situation than
that which I am constantly in? Not one moment of rest either of
mind or body. Mr. Beamish always ready. Poor Isambard always at his
post too, alternately below, or in the barges, and in the
diving-bell.
On July 11, Sir Isambard thought that matters had so far advanced that a
large tarpaulin, which it was proposed to sink over the frames, ‘would
have its full effect.’ It was accordingly sunk on the following day,
under the superintendence of Mr. Brunel. Sir Isambard adds to his
account of the operation--‘This reflects great credit on Isambard, and
the apparent facility with which it was effected evinces his presence of
mind, for a single _faux pas_ would have spoilt the whole.’[21]
_July 21._--During the early part of the night an alarm was given,
by Fitzgerald calling for clay wedges, and exclaiming that the
whole of the faces were coming in altogether. Rogers collected a
quantity of wedges to go to the frames, but no boat was to be seen.
He called to the men in the frames, but received no answer. Taking
the small boat in the east arch, he reached the frames, but found
nobody, nor any appearance of derangement in the ground.
Conjecturing they might be drowned, he explored further, and saw
the four men stretched on the small stage, not drowned, but sound
asleep!
_July 26._--Water nearly out of the arches. For the first time we
could walk to the frames--a most gratifying circumstance indeed!
_Two months and eight days._
_September 30._--How slow our progress must appear to others; but
it is not so, if it is considered how much we have had to do in
righting the frames and in repairing them; what with timbering,
shoring, shipping and refitting--all these operations being in
confined situations, the water bursting in occasionally, and the
ground running in: in short, it is truly terrific to be in the
midst of this scene. If to this we add the actual danger, magnified
by the re-echoing of the pumps, and sometimes (still more awful
warning!) the report of large pieces of cast iron breaking, it is
in no way an exaggeration to say that such has been the state of
things. Nevertheless, my confidence in the shield is not only
undiminished--it is, on the contrary, tried with its full effect,
and it is manifest now that it will soon replace us in good
ground, and in a safe situation. No top staves have given way. That
is our real protection.
_October 17._--At 2.15 A.M. Kemble, having first called upon
Gravatt, came to Isambard in a hurry, and, quite stupefied with
fright, told him that the water was in. Says Isambard--‘I could not
believe him. He said it was up the shaft when he came. This being
like positive, I ran without a coat as fast as possible, giving a
double knock at Gravatt’s door in my way. I saw the men on the top,
and heard them calling earnestly to those whom they fancied had not
had time to escape. Nay, Miles had already, in his zeal for the aid
of others, thrown a long rope, and was swinging it about, calling
to the unfortunate sufferers to lay hold of it, encouraging and
cheering those who might not find it, to swim to one of the
landings. I immediately, I should say instantly, flew down the
stairs. The shaft was completely dark. I expected at every step to
splash into the water. Before I was aware of the distance I had
run, I reached the frames in the east arch, and met there
Pamphillon, who told me that nothing was the matter, but a small
run in No. 1 top, where I found Huggins and the _corps d’élite_.
They were not even aware that any one had left the frames. The
cause of the panic was one of the labourers; hearing the man in No.
1 call for Ball, he ran away, jumping off the stage, crying, “_Run,
run, murder, murder; put the lights out._” His fellow-labourers
followed like sheep, making the same vociferations.’
_November 10._--Isambard gave his entertainment to nearly forty
persons, who sat at table in the Tunnel. Nothing could exceed the
effect for brilliancy. About 120 men partook of a dinner in the
adjoining arch.
As the year drew to a close, the difficulty of working the silt
increased, and with this difficulty increased also the expense of
maintaining the staff of men required. On December 18, Mr. Brunel,
writing for his father, who was absent from town for a few days, thus
describes the nature of the soil through which they were then passing.
The state of the ground over Nos. 1, 2, and 3 top has caused
considerable delay, particularly this week, although not such as to
give any cause of anxiety as to our future rate of progress, or to
have any serious effect except the increased expense incidental to
this delay. My father desired me to describe to the Board the
causes of these difficulties. There is a considerable spring at
this point, and a corresponding soft part in the bed of the river,
which seems to indicate the rising of the spring. The ground in the
neighbourhood is affected by this spring in rather a peculiar
manner: at the half-flood tide the pressure is greatest: dry hard
clay oozes with great force through openings hardly observable, the
silt and water running by starts. At high-water the pressure and
quantity of water begin to diminish and on the ebb-tide the ground
is hard and dry, and can be worked with ease. On the flood-tide
there are as many as twelve and fifteen of the best hands, besides
myself (or one of my assistants) and the foreman, engaged entirely
at one face.
On January 1, 1828, Sir Isambard returned to London; and on the 12th,
when about 600 feet of the Tunnel had been completed, a second irruption
occurred, which put a stop to the works for seven years.
The particulars of this accident are thus described by Mr. Brunel, in a
letter to the Directors of the Company:--
I had been in the frames (shield) with the workmen throughout the
whole night, having taken my station there at ten o’clock. During
the workings through the night, no symptoms of insecurity appeared.
At six o’clock this morning (the visual time for shifting the men)
a fresh set or shift of the men came on to work. We began to work
the ground at the west top corner of the frame: the tide had just
then begun to flow; and finding the ground tolerably quiet, we
proceeded by beginning at the top, and had worked about a foot
downwards, when on exposing the next six inches, the ground swelled
suddenly, and a large quantity burst through the opening thus made.
This was followed instantly by a large body of water. The rush was
so violent as to force the man on the spot, where the burst took
place, out of the frame (or cell) on to the timber stage behind the
frames. I was in the frame with the man, but upon the rush of the
water I went into the next box (or cell), in order to command a
better view of the irruption, and seeing that there was no
possibility of then opposing the water, I ordered all the men in
the frames to retire. All were retiring, except the three men who
were with me, and they retreated with me. I did not leave the stage
until those three were down the ladder of the frames, when they and
I proceeded about twenty feet along the west arch of the Tunnel. At
this moment the agitation of the air, by the rush of water, was
such as to extinguish all the lights, and the water had gained the
height of our waists. I was at that moment giving directions to the
three men, in what manner they ought to proceed in the dark to
effect their escape, when they and I were knocked down, and covered
with a part of the timber stage. I struggled under water for some
time, and at length extricated myself from the stage, and by
swimming and being forced by the water, I gained the eastern arch
where I got a better footing, and was enabled by laying hold of the
railway rope, to pause a little, in the hope of encouraging the men
who had been knocked down at the same time with myself. This I
endeavoured to do by calling to them. Before I reached the shaft
the water had risen so rapidly that I was out of my depth, and
therefore swam to the visitors’ stairs, the stairs for the workmen
being occupied by those who had so far escaped. My knee was so
injured by the timber stage that I could scarcely swim, or get up
the stairs, but the rush of the water carried me up the shaft. The
three men who had been knocked down with me were unable to
extricate themselves, and I am grieved to say, they are lost; and I
believe also two old men, and one young man, in other parts of the
work.
This statement Sir Isambard embodied in a report to the Directors of
January 28, which was circulated among the proprietors.
As soon as the first excitement caused by the irruption had ceased, Mr.
Brunel directed the diving-bell to be prepared in order to ascertain the
state of the shield and the extent of the disturbance of the bed of the
river caused by the rush of water into the Tunnel.
He was, however, so seriously injured that he could not actively
superintend the preparations, but his orders were given with his usual
clearness, calmness, and decision; and as soon as the barge containing
the diving-bell was properly moored over the Tunnel, he was carried out
and laid upon a mattress on the deck of the barge, that he might direct
what was to be done.
As evening came on he became so much worse that he was taken into the
cabin; but everything which took place was reported to him.
At length, the bell being ready, it was lowered early on the Sunday
morning, but the chain not being long enough, proceedings were delayed
until a longer chain could be obtained.
As, however, a chain of the right size and length could not be obtained,
the strongest cable which could be procured in the neighbourhood was
substituted for the chain. A controversy then arose between the
assistant engineers and the foremen as to the sufficiency of the
strength of the cable; and it was agreed to consult and to abide by the
opinion of Mr. Brunel, who was then lying in great pain in the cabin.
No answer could be obtained from him for some minutes, and then he only
said, ‘Don’t go down.’ This not being satisfactory to the advocates of
the sufficiency of the cable, it was agreed to lower the bell empty,
which was done, and it was brought up safely; but just as it was swung
over the barge, the rope broke and the bell fell on to the stage.
The next day Mr. Brunel was taken home, when it was found that, besides
the injury to his knee which he received while endeavouring to save the
lives of the three men who were with him,[22] he had received serious
internal injuries, which kept him under medical treatment for several
months.
When he was able to return to Rotherhithe all hope of continuing the
works was for the time abandoned. When they were resumed, in 1835, he
was entirely engrossed in the independent pursuit of his profession;
and, with the exception of a few occasions when he acted for his father,
he had no further connection with the Tunnel.
It is not, therefore, necessary to continue the narrative in detail; but
a brief summary of the subsequent history of the enterprise may be
interesting to those who are unacquainted with it.
The Tunnel was cleared of water, and efforts were made, unfortunately
without success, to raise funds for the completion of the undertaking.
Great enthusiasm was exhibited by the general public and by many eminent
persons, including the Duke of Wellington; but the money was not
forthcoming, and nothing was left but to brick in the shield, and wait
for more favourable times.
It was not till the beginning of 1835 that the Company was able, by the
aid of a loan from Government, to recommence the works. The old shield
was removed and a new one substituted, in which considerable
improvements were introduced. Slings connecting the frames were added,
which enabled each frame to support its neighbours when necessary, and
important alterations were also made in the arrangements for keeping the
frames at the right distance from one another, and for giving greater
facility of adjustment to the various parts.
Before the Wapping side was reached there were three more irruptions of
the river, namely, August 23, November 3, 1837, and March 21, 1838; but
in October 1840 the shaft on the Wapping shore was commenced. It
differed from the Rotherhithe shaft, in being sunk the whole depth
without underpinning, and was made of a slightly conical form, to reduce
the friction in sinking, and had a larger quantity of iron hoops
introduced into the brickwork, in order to increase its strength. When
this structure had been sunk to the required depth (70 feet), the
excavation of the Tunnel was resumed, and at last the shield was brought
up to the brickwork of the shaft. The operation of making the junction
between the Tunnel and the shaft was one of much difficulty, but it was
at length satisfactorily accomplished, and the Tunnel was opened to the
public on March 25, 1843--eighteen years and twenty-three days after the
commencement of the work.[23]
Sir Isambard Brunel, whose health had for some time been failing, now
retired altogether from his professional labours. After passing a few
years in peaceful and happy seclusion, surrounded by those he loved, and
watched over by their affectionate care, he died on December 12, 1849,
in his 81st year, having been spared to carry to completion his greatest
work, and to see his son following in his footsteps with a success which
must have exceeded his most sanguine expectations.
* * * * *
The education Mr. Brunel received from his father was well calculated to
form the foundation of his future career. During the later and more
arduous part of the contest, which was ended by the irruption of January
1828, he held both the nominal and actual post of Resident Engineer of
the Thames Tunnel; but from the commencement of the works, when he was
only nineteen years old, he had been, as stated by Sir Isambard, ‘a most
valuable coadjutor in the undertaking.’ While placed in this responsible
position he acquired habits of endurance and of self-reliance, and
learnt to act with promptitude and decision in the application of those
measures which experience had shown to be effective in each particular
class of emergency. But beyond all other advantages, he had before him
the example of his father’s character, in which a rare degree of
gentleness and modesty of disposition was joined to unflinching energy,
and a determination to overcome all difficulties.
NOTE A (p. 5).
_The Bourbon Suspension Bridges_.[24]
The suspension bridges designed by Sir Isambard Brunel for crossing
rivers in the Ile de Bourbon were two in number. One of them had two
spans of 122 feet each in the clear, and 131 feet 9 inches between the
points of suspension of the chains. The second had but one span of the
same dimensions as those of the larger bridge. In the design of these
bridges one of the most important points to be attended to, was to
render them secure against hurricanes, which are both frequent and
severe in the Ile de Bourbon.
In the larger bridge there was a pier of masonry, built in the middle of
the river up to the level of the roadway of the bridge. The suspension
chains of the bridge were in three groups, 9 feet 8 inches apart, so as
to leave room for two roadways, each about 8 feet 9 inches wide. Each of
these groups of chains consisted of two chains side by side. Each chain
was made with long links like those of the chain cables used for
moorings.
These links, which were made of iron 1·36 inch in diameter, were 4 feet
8 inches long, inside measure, and were each connected together by two
short coupling links, 8¾ inches long, inside measure, of iron 1·36 inch
by 1 inch, and two pins, each two inches in diameter.
The two chains of each group were placed side by side, with the links
upright; one of the pins at each joint was made long enough to serve for
both chains, and, in the middle of its length between the two chains,
was passed through an eye at the upper end of one of the suspending rods
of the bridge. Thus to every joint in each group of the main chains, or
at intervals of about 5 feet, there was a suspending rod. These rods
were 1¼ inch in diameter.
The pins of the joints of the main chains had half heads at each end of
them. They could thus be easily inserted in erecting the bridge, but
once in place were quite secure. At every fourth joint in the main
chains one of the joint pins was made in two halves, with wedges
inserted between them for adjusting the length of the main chains.
Thus there were six chains, and as the links of these had each two parts
of iron 1·36 inch in diameter, the total sectional area of the six
chains was 17·4 inches.
Each group of the main chains was supported at a height of 25 feet 6
inches above the roadway at the centre pier, and at a height of 5 feet 3
inches at each of the side piers, the lowest portion of the curve of the
chain being about 1 foot below the points of suspension of the side
piers.
The upright standards, carrying the chains both at the centre pier and
at the side piers, consisted for each group of chains of a triangular
framework of cast iron, strengthened by long bolts of wrought iron.
There were thus three of these triangular frames parallel to each other
at each of the piers, and those at the centre pier were braced together
over the carriage road. The main chains were not bolted to the
standards, but were slung from them by a vertical suspension link, which
thus allowed them to move a little lengthways. This link, in fact,
performed the function of the rollers now generally put under the
saddles of suspension bridges.
The ends of the main chains were held by back stays, formed of bars 3
inches broad by 1¼ inch thick, and 10 feet long, with joints made with
short links, and 2⅜ inch pins. The ends of those back stays were
secured to holding down plates 3 feet in diameter, sunk deep in the
ground and well loaded.
As there was a vertical suspension rod at each joint of the main chains,
there was a suspension rod hanging from each of the three groups of
chains at about every five feet of the length of the bridge. To each set
of these rods was attached a cross girder of cast iron of a =T= section,
with a large rounded bead at the lower edge of the upright web; and
connecting these under each of the main chains was a longitudinal timber
beam about 8 inches square.
The cast-iron cross girders carried longitudinal teak planking, the
planks on which the carriage wheels ran being 12 inches wide and 4
inches thick, protected at the top by wrought-iron plates running
longitudinally. The horse-path was protected by iron plates arranged
crosswise.
Under each span of the bridge were four chains curved upwards and also
sideways. These chains were fastened at their ends into the piers, and
were connected to the roadway by ties drawn up tight and attached to the
main longitudinal bearers of the platform; the object being to stiffen
the platform.
These under tie chains were made each of a set of rods 1¼ inch in
diameter with eyes at their ends, the ends being connected by short
joint links and 1¼ inch pins; and to these joint links were attached the
tie rods which connect these inverted chains with the platform of the
bridge, and so prevented its being lifted or blown sideways by the force
of the wind.
In the smaller bridge, which, as has been said, consisted of one span of
131 feet 9 inches between the points of suspension, these points were 15
feet 5 inches above the roadway, and the lowest part of the chain was 9
feet 7 inches below the points of suspension. The details of this bridge
were similar to those of the larger one.
NOTE B (p. 5).
_Experiments with Carbonic Acid Gas._
In 1823 Mr. Faraday made the important discovery that under certain
conditions of temperature and pressure many gases could be liquefied,
and that these liquids exerted great expansive force by slight additions
of temperature, returning quickly with regularity and certainty to their
original state upon the application of cold.
The discovery of this new force appeared of such importance, that Mr.
Faraday lost no time in publishing it to the world; and Sir Isambard
Brunel very soon afterwards commenced a series of experiments to
determine the value of the liquid gas as a mechanical agent.
The first experiments were made at Chelsea; but the prosecution of them
was soon transferred to the care of Mr. Brunel at Rotherhithe, where he
devoted all his spare time to the construction of his father’s proposed
‘Differential Power Engine.’
That the progress of this discovery, and of the experiments made with a
view to the application of the liquid gas, as a motive power, may be
understood, it is necessary to state that in March 1823 Mr. Faraday
communicated to the Royal Society the results of his first experiments
on the liquefaction of gases.
The fluid was then produced by the decomposition of the hydrate of
chlorine by heat in a closed tube, the amount of gas evolved being so
great as to produce a pressure in the tube sufficient to condense the
gas into a fluid of the same volume.
This interesting experiment was followed by others with that rapidity
and success so remarkable in everything undertaken at that time in the
laboratory of the Royal Institution; and within a month another paper
was read before the Royal Society, in which the degrees of pressure and
temperature at which several gases could be liquefied were recorded, and
the means employed to produce and liquefy each gas accurately described.
On April 17 a third paper was communicated by Mr. Faraday, ‘On the
Application of Liquids produced by the Condensation of Gases as
Mechanical Agents.’
The question is thus stated: ‘The ratio of the elastic force dependent
upon pressure is to be combined with that of the expansive force
dependent on temperature; and the development of latent heat on
compression and the necessity of its reabsorption in expansion must
awaken doubts as to the economical results to be obtained by employing
the steam of water under very great pressures and very elevated
temperatures.
No such doubt can arise respecting liquids, which require for their
existence even a compression equal to thirty or forty atmospheres, and
where slight elevations of temperature are sufficient to produce an
immense elastic force, and where the principal question arising is
whether the effort of mechanical motion is to be most easily produced by
an increase or diminution of heat by artificial means.’
Difficulties were suggested by Mr. Faraday as to the possibility of
obtaining sufficient strength in the apparatus, but the small difference
of temperature required to produce an elastic force of many atmospheres,
he considered would render the risk of explosion small.
To construct the machinery whereby this new force could be practically
applied as a substitute for steam, occupied the time of Sir Isambard
Brunel and his son at intervals for several years; for although Mr.
Brunel was satisfied at an early period of the enquiry that the
liquefied gases could only be advantageously employed where the cost of
motive force was secondary to economy of space and to the avoidance of
the cumbrous apparatus required for the use of steam, still he was so
impressed with the importance of the subject, if the difficulties he
foresaw in its application could be overcome, that he continued his
experiments for a long period with unflagging energy and perseverance.
The facts relating to the liquefaction of the gases, their elastic force
when liquefied under different temperatures, the rapidity with which
they could be alternately expanded and condensed, and the best mode of
producing each gas, were determined by Mr. Faraday; and as Mr. Brunel
was at that time attending the morning chemical lectures at the Royal
Institution, he was in constant communication with him, and thoroughly
conversant with his experiments.
After Mr. Brunel had made a few preliminary experiments, Sir Isambard
determined to employ liquefied carbonic acid gas for the motive power of
the proposed new engine, the facility and cheapness of its production,
its great expansive force, and its neutral character distinguishing it
from any other gas; but it was long before vessels were constructed, in
which gas could be produced in sufficient quantity and purity to exert
the force required to liquefy it in its own volume, for it was soon
found to be impossible to obtain the required pressure with pumps.
Carbonate of ammonia and sulphuric acid were the elements used, and the
generator was so arranged that it could be charged, emptied of
atmospheric air, and the joints made perfect, before the commencement of
the formation of the gas which was to be liquefied.
To the generator was attached a receiver, which could be surrounded with
a freezing mixture, so that the temperature of the gas in the cylinder
might be below that in the generator.
The gradual formation of the liquid, the development of its elastic
force, and the regularity and rapidity with which it increased or
diminished by each degree of heat or cold, were carefully watched
through a glass gauge, and the receiver when filled with liquid could be
disconnected from the generator.
The mechanical difficulties as they arose, one after the other, in the
construction and arrangement of the various parts of the generator and
receiver were at length overcome; and the receiver was not only filled
with liquid gas, but found to be capable of retaining it, whether
exerting an elastic force of 30 atmospheres at ordinary temperatures, or
of 100 atmospheres when subjected to a slight degree of heat.
The receiver being satisfactorily completed, the next object of
attention was the design and construction of a working cylinder capable
of resisting at least 1,400 lbs. pressure on the square inch; a task
which was one of great anxiety, as any weakness might have caused a
serious accident.
It was only after the trial of every known method of making joints to
resist high pressures had failed, that an arrangement was devised,
requiring the most perfect workmanship, by which packing of any kind was
dispensed with, and the cylinder fitted for use.
With the improved tools of the present day it is not easy to realise the
difficulties, delays, and disappointments which forty-five years ago
occurred from the failure, first of one part of a joint, and then of
another; but the construction of vessels capable of producing and also
of retaining the gas in its liquid state, with the means of alternately
expanding and condensing it from thirty or forty to eighty or one
hundred atmospheres, having been accomplished, the object of the
expenditure of so much labour and inventive power appeared to be within
reach.
The construction of the machinery to utilise the elastic force contained
in the cylinder was now proceeded with. Day by day new difficulties
arose, and each as it was successfully met seemed but to leave another
of greater importance to be surmounted.
It is not necessary in this Note to describe the various arrangements
which were devised for transferring the great elastic force in the
cylinder of small diameter to a piston in another cylinder of much
larger dimensions; it is sufficient to say, that after the devotion of
much valuable time extending over several years, and a very large
expenditure of money, and after carefully considering the cost of the
liquid carbonic acid gas, the difficulty of preventing waste, and the
necessarily very expensive character of the machinery, Mr. Brunel was
satisfied ‘that no sufficient advantage in the sense of economy of fuel
can be obtained by the application of liquefied carbonic acid gas as a
motive power’; but so thoroughly did he exhaust the subject before he
committed himself to this opinion, that no one has since renewed the
enquiry or attempted to make a machine to be moved by the elastic force
of liquefied gases, the construction of which, it was well known, had
baffled the inventive genius of Sir Isambard Brunel and his son.