_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).
Under any circumstances, and by whomsoever made, the attempt to describe
Mr. Brunel’s home life must fail to satisfy those who knew him, and who
remember him in the midst of his family or among his friends.
But those who did not know him, except as a professional man, or who are
only acquainted with his works, will expect to find in these pages some
account of his private life, and of the manner in which he spent those
brief intervals of relaxation which he permitted himself to enjoy.
* * * * *
Although Mr. Brunel was never an idle man, he was able, until he
obtained business on his own account, to enjoy many amusements from
which in after life he was completely debarred.
This arose partly from his work under his father being near his own home
and his friends, and partly from the power he possessed, and which never
deserted him, of being able to throw aside cares and anxieties and to
join with the utmost zest in passing amusements.
The following letter, relating to this time, is written by one who was
Mr. Brunel’s constant companion during the period to which it refers:--
June 28, 1870.
‘Dear Isambard Brunel,--I will endeavour to supply you with some
reminiscences of your father, before he became a public man, and
was engrossed by the very severe labour of his profession.
‘The most striking feature in his character as a young man, and one
which afterwards produced such great results, was an entire
abnegation of self in his intercourse with his friends and
associates.
‘His influence among them was unbounded, but never sought by him;
it was the result of his love of fair play, of his uniform kindness
and willingness to assist them, of the confidence he inspired in
his judgment, and of the simplicity and high-mindedness of his
character.
‘From 1824 to 1832 he joined his friends in every manly sport; and
when, after his accident at the Tunnel, he was obliged to withdraw
from more violent exercise, he was still ready to co-operate in the
arrangements required to give effect to whatever was in hand.
‘Whether in boating, in pic-nic parties, or in private theatricals,
he was always the life and soul of the party; for his skilful
arrangements, as well as his never-failing invention and power of
adaptation of whatever came to hand, made him the invariable leader
in every amusement or sport in which he took part.
‘To ensure the success of his friends in a rowing match against
time, from London to Oxford and back, in 1828, he designed and
superintended the building of a four-oared boat, which, in length
and in the proportion of its length to its breadth, far exceeded
any boat of the kind which had then been seen on the Thames.
‘During that portion of the period to which these notes refer, when
your father was engaged at the Tunnel works, the freshness and
energy with which he joined in the amusements of his friends after
many consecutive days and nights spent in the Tunnel--for
frequently he did not go to bed, I might almost say, for weeks
together--surprised them all.
‘His power of doing without sleep for long intervals was most
remarkable. He also possessed the power, which I have never seen
equalled in any other man, of maintaining a calm and even temper,
never showing irritation even when he was bearing an amount of
mental and bodily fatigue which few could have sustained. His
presence of mind and courage never failed him, and it was
especially exhibited after the first irruption of water into the
Tunnel, when he descended in the diving-bell to examine the extent
of the disturbance of the bed of the river, and the injury, if any,
which had been done to the brickwork.
‘The bell could not be lowered deep enough, and he dropped himself
out of the bell, holding on by a rope, and ascertained by careful
examination that the brickwork was uninjured.
‘He was several minutes in the water; and upon this fact being
stated, many persons, and I think the officers of the Royal Humane
Society, denied the possibility of his retaining his consciousness
so long in the water, forgetting, which he did not, that his lungs
were filled with air at two and a half atmospheres’ pressure.
‘In 1830, he joined the Surrey Yeomanry and attended drill, and was
out with the troop to which he belonged on several occasions.
‘In this capacity he was as popular as in every other; but his
remarkable talent in obtaining personal influence, even among those
with whom he was comparatively a stranger, was about this time most
usefully exhibited during the election of his brother-in-law as
member for Lambeth.
‘He made friends and conciliated opponents among all classes of
electors--especially among working men, large bodies of whom he met
on several occasions--and among all shades of politicians; and to
his energy, good judgment and skilful arrangement of electioneering
details, which were not then so well understood as they now are,
very much of the success achieved was due.
‘No one, I believe, ever saw him out of temper or heard him utter
an ill-natured word. He often said that spite and ill-nature were
the most expensive luxuries in life; and his advice, then often
sought, was given with that clearness and decision, and that
absence of all prejudice, which characterised his opinions in
after-life.
‘All his friends of his own age were attached to him in no ordinary
degree, and they watched every step in his future career with pride
and interest.
‘In fact, he was a joyous, open-hearted, considerate friend,
willing to contribute to the pleasure and enjoyment of those about
him; well knowing his own power, but never intruding it to the
annoyance of others, unless he was thwarted or opposed by
pretentious ignorance; and then, though at times decided and severe
in his remarks, he generally preferred leaving such individuals to
themselves, rather than, by noticing them, to give prominence to
their deficiencies.
‘His appreciation of character was so exact, and his dislike to
anything approaching to vulgarity in thought or action or to undue
assumption was so decided, that to be his friend soon became a
distinction; and the extent to which his society was sought, not
only in private life, but in the scientific world, at this early
period, marked strongly the distinguishing features of his mind and
character.
‘In 1825 and 1826 he attended the morning lectures at the Royal
Institution, and the eagerness and rapidity with which he followed
the chemical discoveries which were then being made by Mr. Faraday,
showed the facility with which he gained and retained scientific
knowledge.
‘To write more would lead me to the events of a later period of his
life, in the history of which you require no aid from me;
nevertheless, I cannot refrain from adding a few words upon your
father’s personal and professional character, which was not, in my
opinion, adequately appreciated by the public.
‘His professional friends before his death, and his private friends
at all times, well knew the genius, the intense energy, and
indefatigable industry with which every principle and detail of his
profession was mastered; and both knew and valued the high moral
tone which pervaded every act of his life.
‘The public, however, did not see him under the same circumstances.
‘Their imperfect acquaintance with his character arose in a great
degree from his disregard of popular approbation, for he was never
so satisfied with his own work as to feel himself entitled to
receive praise in the adulatory style of modern writing, and he
preferred to work quietly in his own sphere, and to rely on the
intrinsic merits of his undertakings bringing their reward, rather
than to court temporary popularity.
‘The rapidity with which he gained a high position as a civil
engineer is the best evidence of his talents. He passed almost
direct from boyhood to an equality with any one then in the
profession--a position attained by the rapidity and accuracy with
which he could apply theory to practice, and support his
conclusions by mathematical demonstrations.
‘This knowledge, always used without ostentation, soon placed him
above most of his contemporaries; and his intimate acquaintance
with the strength and peculiarities of the various materials he had
to employ, and of the best and most economical mode of applying
them, impressed both directors and contractors with a degree of
confidence in his estimates and opinions which no one had before
possessed.
‘His power of observation was singularly accurate; he was not
satisfied with a hasty or superficial examination, nor with the
mere assertion of a fact; his mind required evidence of its
correctness before he could receive and adopt it. I may illustrate
this by a reference to the experiments he made with French
mesmerists, and the pains he took to expose the farce of
table-turning and its accompanying follies.
‘My object, however, by this addition to my note, is to dwell upon
the fact that he left a mark upon his profession which cannot be
obliterated. He set up a high standard of professional excellence,
and endeavoured to impress on all who were associated with him, or
under him professionally, that to attain the highest honours
required the strictest integrity, sound mathematical knowledge,
originality and accuracy of thought and expression, both in _viva
voce_ descriptions and in designs and working drawings, and a
practical acquaintance with the durability and strength of
materials, so as to know the best conditions under which each might
be applied.
‘It was his excellence in these respects, when still young, which
soon earned for him a great reputation as a witness before the
Committees of the Houses of Parliament.
‘His calmness and unobtrusive manner, when under severe
examination, or while attending public meetings, led many to think
him cold, and regardless of the feelings or interests of those with
whom he was associated; but nothing was further from his character,
as every one knew who was engaged in the consultations upon the
result of which future proceedings depended.
‘He was a prudent and cautious, but bold adviser, and a
warm-hearted and generous friend.
‘Yours faithfully,
‘W. HAWES.
‘Isambard Brunel, Esq.’
The events of the year 1835 brought with them, not unnaturally, other
changes. At the beginning of 1836, he removed to 18 Duke Street,
Westminster, a large house looking on St. James’s Park, and now (1870)
the last in the street, next to the new India Office.
In July of the same year he married the eldest daughter of the late
William Horsley, and granddaughter of Doctor Callcott. Of this marriage
there was issue two sons and a daughter, all of whom survive him.
Although, as will be presently mentioned, he afterwards bought some
property in Devonshire, the Duke Street house was always his home. He
spent his life there, having his offices on the lower floors.
He had no wish to enter Parliament, although it had been more than once
suggested to him to do so, and his work prevented his taking an active
share, as an inhabitant of Westminster, in the concerns of his
neighbourhood.
The only occasion on which he took a prominent part in local affairs
was as a special constable in April 1848, when he acted as one of the
two ‘leaders’ of the special constables in the district between Great
George Street and Downing Street.
He was not without experience of the duties of a special constable, as
he had been sworn in during the Bristol riots of 1830, and on that
occasion saw active service. Happily, matters were better managed in
London, and no actual collision took place between the constables, or
the military, and the mob.
* * * * *
The extent to which Mr. Brunel kept his works in his own hands, and
under his own superintendence, made it necessary for him to have a large
amount of office accommodation; and the inconvenience of having branch
offices in the streets near his house led him, in 1848, to enlarge his
offices: with this object he added the adjoining house, 17 Duke Street,
which he rebuilt. A large room on the ground floor, looking on the Park,
was thenceforward his own office, and the room above was made the
dining-room. It was decorated in the Elizabethan style, and was to have
contained a collection of pictures illustrative of scenes in
‘Shakespeare,’ painted for him by the principal artists of the day. This
project was never completely carried out, but several pictures (about
ten in all) were painted and hung up, among them the ‘Titania’ of Sir
Edwin Landseer. These subjects are again referred to in the following
letter:--
February, 1870.
‘My dear Isambard,--You ask me to jot down for you any
reminiscences I have of your father’s love and feeling for art.
‘I remember with singular distinctness the first time I ever saw
him, when I was a lad of fourteen, and had just obtained my
studentship at the Royal Academy. He criticised with great keenness
and judgment a drawing which I had with me, and at the same time
gave me a lesson on paper straining. From that time till his death
he was my most intimate friend. Being naturally imbued with
artistic taste and perception of a very high order, his critical
remarks were always of great value, and were made with an amount of
good humour which softened their occasionally somewhat trying
pungency. He had a remarkably accurate eye for proportion, as well
as taste for form. This is evinced in every line to be found in his
sketch books, and in all the architectural features of his various
works.
‘So small an incident as the choice of colour in the original
carriages of the Great Western Railway, and any decorative work
called for on the line, gave public evidence of his taste in
colour; but those who remember the gradual arrangement and fitting
up of his house in Duke Street will want no assurance from me of
your father’s rare artistic feeling. He passed, I believe, the
pleasantest of his leisure moments in decorating that house, and
well do I remember our visits in search of rare furniture, china,
bronzes, &c., with which he filled it, till it became one of the
most remarkable and attractive houses in London. Its interest was
greatly increased when he formed that magnificent dining-room, now,
with the house of which it was a part, pulled down. This room, hung
with pictures, with its richly carved fireplace, doorways, and
ceiling, its silken hangings and Venetian mirrors, lighted up on
one of the many festive gatherings frequent in that hospitable
house, formed a scene which none will forget who had the privilege
of taking part in it. When from time to time he went abroad, and
especially in his visit to Venice in 1852, he added to his
collection by purchases made with great judgment and skill. In
buying pictures, your father evinced a taste often found in men of
refined mind and feeling--viz. a repugnance to works, however
excellent in themselves, where violent action was represented. He
preferred pictures where the subject partook more of the suggestive
than the positive, and where a considerable scope was left in which
the imagination of the spectator might disport itself. This feeling
was displayed in a great love of landscape art, and in the keenest
appreciation of the beauties of nature. It is an interesting fact
to record, and one which I often heard him mention, when his
friends were admiring his beautiful grounds at Watcombe, that in
the old posting days, when travelling on the cliff road between
Teignmouth and Torquay, he constantly stopped the carriage to get
out and admire the view which he had discovered from a field at
Watcombe, little thinking then that it would ultimately be the site
of his intended country home.
‘When your father and I went to Italy together in 1842, posting
from Westminster to Rome and back again, I had ample opportunities
of observing his love and enthusiasm for nature and art.
‘Overwhelmed as he was with work in England at the time, it was no
easy matter for him to leave the country for a couple of months;
and I remember that our starting at all was uncertain up to the
last moment; and that, an hour before quitting London, it was only
by a _coup de théâtre_, which he most adroitly performed, that he
escaped the serving of a subpœna, the bearer of which had
actually penetrated to the dining-room door in Duke Street.
‘We left London one evening in April 1842. During our journey we
constantly passed several consecutive days and nights in the
carriage; and I am sure there was not one of our waking hours in
which some incident of interest did not occur.
‘I remember your father agreeing with me, that our experiences
merely of post-boys and their various characteristics would be
worthy of recording in detail--from Newman’s two smart lads, who
took us the first stage out of London, on to the genuine
“postillon” (boots and all) we found at Calais; then to the wild
young brigands (in appearance) who, inspired by the prospect of
extra “buon mano,” whirled us along the road from Civita Vecchia
towards Rome, and winding up with the stolid German who rose slowly
in his stirrups, and distracted us by a melancholy performance on
the horn slung round him, and which no entreaty would induce him to
give up.
‘We posted from Calais, _viâ_ Paris, to Châlons-sur-Saône,
marvelling the whole way whereabouts “La Belle France” was to be
found; for a drearier and more utterly monotonous ride of something
like 800 miles it is impossible to conceive. From Châlons we went
down the river to Lyons, then onwards, visiting Nismes, and through
Arles to Toulon.
‘From Toulon we went through Cannes and Nice and along the lovely
Cornice road to Genoa. Your father was intensely delighted with
this portion of the journey. Those wonderfully picturesque towns,
with their roccoco churches looking like toys, and painted all over
upon the principle of colour generally developed in that species of
art, especially interested him. The streets were so narrow that it
was sometimes doubtful whether the carriage could be squeezed
through, and more than once it grazed the houses on either side as
it passed on.
‘The work for which your father had come to Italy commenced at
Genoa, and he was met there by a staff appointed by the Government
to accompany him during his stay.
‘While at Genoa he came to me one morning and said, that, in
consequence of some delay, he had a week in which to make complete
holiday, and gave me the choice of Florence or Rome. I need
scarcely say that I chose Rome, and for three days we were in the
Eternal City, seeing more in that time than those to whom we
related our proceedings could believe.
‘How well do I remember our entering Rome by the gate on the Civita
Vecchia road, and standing up in the carriage to get our first view
of St. Peter’s, and, having seen it, the blank look of
disappointment we turned on each other at the sight! But the
interior of the great church as far exceeded our expectations as
the exterior had fallen short of them.
‘We were back at Genoa to the minute your father had appointed; and
the work being completed there, we went on to Turin. Here we were
in time to be present at the Court balls and ceremonies consequent
upon the marriage of the present King of Italy.
‘From Turin we proceeded to Milan.
‘At Milan your father parted from his staff, and completed the work
he had undertaken as far as it was necessary to do so in Italy.
From Milan, therefore, our journey home was one of uninterrupted
enjoyment through those glorious Lombard towns to Venice, which
happily we reached in a gondola from Mestre, and not by a railway
viaduct; then through the Tyrol to Munich, and so down the Rhine to
Belgium, reaching home from Antwerp.
‘Thus was completed an expedition in which there was neither hitch
nor disagreeable adventure of any kind, and upon which I look back
with unmixed pleasure.
‘The next and last time that your father and I journeyed on the
Continent together was in April 1848, when he wished to see Paris
in Republican garb, and asked me to accompany him.
‘We were there for some days, and, armed with cards of admission,
on which our names were inscribed with the prefix of “Citoyen,”
heard and saw the various celebrities of the hour.
‘Affectionately yours,
J. C. HORSLEY.
‘Isambard Brunel, Esq.’
Within less than a year of Mr. Brunel’s return from his visit to Italy,
a strange accident happened to him, which placed his life in great
jeopardy.
On April 3, 1843, he was amusing some children at his house by the
exhibition of conjuring tricks, when, in pretending to pass a
half-sovereign from his ear to his mouth, the coin he had placed in his
mouth slipped down his throat. After a few days he began to suffer from
a troublesome cough, and on April 18 Sir Benjamin Brodie was consulted.
The nature of the accident and the course of treatment adopted are
described in the following letter from Mr. Brunel’s brother-in-law, the
late Dr. Seth Thompson, which was published in the ‘Times’ newspaper of
May 16, 1843:--
I shall be much obliged by your giving insertion to the following
statement of the treatment pursued by Sir Benjamin Brodie in the
case of Mr. Brunel, it being the wish of Mr. Brunel and his friends
that the true facts should be known, as a just tribute to the skill
of this eminent surgeon, and as a guide to future practice. The
accident happened on April 3; Sir B. Brodie was consulted on the
18th, and his opinion was that the half-sovereign had passed into
the windpipe. The following day Mr. Brunel strengthened this
opinion by a simple experiment. He bent his head and shoulders over
a chair, and distinctly felt the coin drop towards the glottis;
whilst raising himself a violent fit of coughing came on, which
ceased after a few minutes. He repeated this a second time, with
the same results. A consultation was held on the 22nd, at which it
was decided that conclusive evidence existed of the half-sovereign
having passed into the windpipe, that it was probably lodged at the
bottom of the right bronchus, and that it was movable. It was
determined that every effort should be made for its removal, and
that for this purpose an apparatus should be constructed for
inverting the body of the patient, in order that the weight of the
coin might assist the natural effort to expel it by coughing. The
first experiment was made on the 25th. The body of the patient
being inverted, and the back gently struck with the hand between
the shoulders, violent cough came on, but of so convulsive and
alarming a nature that danger was apprehended, and the experiment
was discontinued. On this occasion the coin was again moved from
its situation, and slipped towards the glottis. On the 27th
tracheotomy was performed by Sir B. Brodie, assisted by Mr. Aston
Key, with the intention of extracting the coin by the forceps, if
possible, or, in the event of this failing, with the expectation
that the opening in the windpipe would facilitate a repetition of
the experiment of the 22nd. On this occasion, and subsequently on
May 2, the introduction of the forceps was attended with so much
irritation, that it could not be persevered in without danger to
life. On the 3rd another consultation was held, when Mr. Lawrence
and Mr. Stanley entirely confirmed the views of Sir B. Brodie and
Mr. Key, and it was agreed that the experiment of inversion should
be repeated as soon as Mr. Brunel had recovered sufficient
strength, the incision in the windpipe being kept open. On
Saturday, the 13th, Mr. Brunel was again placed on the apparatus,
the body inverted, and the back gently struck. After two or three
coughs, he felt the coin quit its place on the right side of the
chest, and in a few seconds it dropped from his mouth without
exciting in its passage through the glottis any distress or
inconvenience, the opening in the windpipe preventing any spasmodic
action of the glottis.
In this remarkable case the following circumstances appear to be
worthy of note--that a piece of gold remained in the air-tube for
six weeks, quite movable, and without exciting any inflammatory
action, the breathing entirely undisturbed, and the only symptoms
of its presence occasional uneasiness on the right side of the
chest and frequent fits of coughing; that an accurate diagnosis was
formed without being able to obtain any assistance from the
stethoscope, although the chest was repeatedly and carefully
examined; and also that, a fair trial having been given to the
forceps, the application of this instrument to the removal of a
body of this peculiar form from the bottom of the bronchus was
proved to be attended with great risk to life, while the cautious
and well-considered plan of treatment above detailed was attended
with complete success, and without risk.
During the time that Mr. Brunel was in danger the public excitement was
intense. His high professional position, the extraordinary nature of the
accident, and the greatness of the loss, were the result to prove fatal,
made his condition and the chances of his recovery an engrossing topic
of conversation; and, when the news was spread that ‘it is out,’ the
message needed no explanation.
That the result was successful was due, not only to the skill of the
surgeons engaged, and to the anxious care with which those who nursed
him left nothing undone to ensure his safety, but also to the remarkable
coolness which Mr. Brunel himself displayed throughout. From the first
he took part in the consultations which were held on his case, and
assisted materially in determining the course of treatment which should
be pursued.
* * * * *
The ten years which followed were the most prosperous in Mr. Brunel’s
life; he had attained to great eminence in his profession, and was still
in the enjoyment of robust health. But the results of the gauge
controversy and the fierce contests which followed it, and, above all,
the failure of the Atmospheric System on the South Devon Railway, caused
him grave anxiety and sorrow. Critics have erred greatly in representing
him as a man who, in order to accomplish some vast design, thought but
little of the distress which follows want of success in commercial
enterprises. So far from its being true that Mr. Brunel was indifferent
to the interests of his employers, his private journals show that
throughout (to use his own words) ‘the incessant warfare in which he was
engaged’ he was earnestly desiring peace and endeavouring to secure it,
and that in times of difficulty, such as the trial of the Atmospheric
System and the launch of the ‘Great Eastern,’ his chief thoughts were
for those who would suffer through the failure of his plans.
* * * * *
In the midst of his professional occupations he was able occasionally,
though rarely, to enjoy the society of his friends. After the session
was over, in 1844 and 1845, he went to Italy on business, and in 1846 to
Switzerland for a short holiday. In 1847 the South Devon Railway was
occupying his attention, and he determined to take a house at Torquay.
While there, the important character of his railway works in Devonshire
and Cornwall led him to think of making a more permanent settlement in
that part of the country.
After a good deal of hesitation between various places, he fixed upon a
spot at Watcombe, about three miles from Torquay, on the Teignmouth
turnpike road. He made his first purchase of land in the autumn of 1847;
and from that time to within a year of his death the improvement of this
property was his chief delight.
He had always a great love and appreciation of beautiful scenery, and in
his choice of a place in which to plant and build he provided amply for
his complete gratification.
The principal view, which, if the house had been built, would have been
the view from the terrace, is one of the loveliest in that part of
Devonshire. On one side is the sea, and on the other the range of
Dartmoor, while in front is spread undulating country, bounded by the
hills on the further side of Torbay, the bay itself looking like a lake,
being shut in by the hills above Torquay.
When Mr. Brunel bought this property it consisted of fields divided by
hedgerows; but, assisted by Mr. William Nesfield, he laid it out in
plantations of choice trees. The occupation of arranging them gave him
unfailing pleasure; and, although he could seldom spare more than a few
days’ holiday at a time, there can be little doubt that the happiest
hours of his life were spent in walking about in the gardens with his
wife and children, and discussing the condition and prospects of his
favourite trees.[193]
He could not, of course, take a prominent part in the affairs of the
parish, but he was always ready to assist in any work that had been
taken in hand. He will be long remembered there by his friends in every
rank of life.
In purchasing this property in Devonshire, Mr. Brunel had looked forward
to retiring gradually from active professional life, ‘to draw in and
make room for others,’ and to spend a greater portion of his time in the
country.
It may well be questioned whether he would have been happy in giving up
work while yet in middle life; but the wisdom of his resolve was not to
be put to the test.
From the beginning of the year 1852 the ‘Great Eastern’ steam-ship began
to occupy his time and thoughts. As the works progressed he was more and
more tied to London; and the large pecuniary investment he had made in
the shares of the company caused him to hesitate before proceeding with
the building of his house.
Thus the hopes he had formed for making his home in Devonshire faded
gradually away, and were at length extinguished by the failure of his
health.
* * * * *
Many things had happened in the earlier part of 1857 which gave him
pleasure. In June he received, in company with Mr. Robert Stephenson,
the honorary degree of Doctor in Civil Law from the University of
Oxford.[194] In the summer he paid several visits to Devonshire, and at
the beginning of September the floating of the first truss of the
Saltash bridge was successfully accomplished.
The history of the launch of the ‘Great Eastern,’ which was commenced in
November, has been already told. Throughout all the disappointments he
then endured Mr. Brunel took comfort from the sympathy of valued
friends, and from those higher sources of consolation on which it was
his habit to rely. He paid for his exertions a heavy price, for they
left him broken in health and already suffering from the disease of
which in a little more than eighteen mouths afterwards he died.[195]
* * * * *
In May 1858 Mr. Brunel went to Vichy, and thence to Switzerland,
returning home in the autumn by way of Holland. When at Lucerne he went
up the Righi, and was so charmed with it that, instead of spending only
a night there, he remained a week, working at the designs for the
Eastern Bengal Railway.
It was on his return to England in September that the alarming nature of
his illness was ascertained. After anxious consultation with Sir
Benjamin Brodie and Dr. Bright, he was ordered to spend the winter in
Egypt, in the hope that he might return in the March or April following
in restored health.
He was very unwilling to be so long absent from England, especially as a
new company had just been formed to finish the ‘Great Eastern,’ and the
contracts for her completion were about to be let.
However, it was thought that very serious consequences might follow if
he remained at home; and in the beginning of December he left for
Alexandria, with his wife and younger son.
Having stayed there a day or two, they went on to Cairo, where they
found Mr. Robert Stephenson. He and Mr. Brunel dined together on
Christmas Day.
On December 30 the journey up the Nile commenced. On January 21 they
arrived at Thebes, and spent some days there. Mr. Brunel was able to
ride about on a donkey, and made some sketches of the celebrated ruins
in the neighbourhood.[196]
They reached Assouan on February 2, and made preparations for ascending
the cataracts. They went as far as Dakkeh, and got back to Assouan on
February 19.
The following letter from Mr. Brunel to his sister, Lady Hawes,
describes some of the scenes through which he passed:--
Philæ, February 12, 1859.
I now write to you from a charming place; but Assouan, which I
left to come here, is also beautiful, and I will speak of that
first. It is strange that so little is said in the guide books of
the picturesque beauty of these places. Approaching Assouan, you
glide through a reef of rocks, large boulders of granite polished
by the action of the water charged with sand. You arrive at a
charming bay or lake of perfectly still water and studded with
these singular jet-black or red rock islands. In the distance you
see a continuation of the river, with distant islands shut in by
mountains, of beautiful colours, some a lilac sandstone, some the
bright red yellow of the sands of the desert. Above the
promontories the water excursions are delicious. You enter at once
among the islands of the Cataracts, fantastic forms of granite
heaps of boulders split and worn into singular shapes.
After spending a week at Assouan, with a trip by land to Philæ, I
was so charmed with the appearance of the Cataracts as seen from
the shore, and with the deliciously quiet repose of Philæ, that I
determined to get a boat, and sleep a few nights there. We
succeeded in hiring a country boat laden with dates, and emptied
her, and fitted up her three cabins.[197] We put our cook and
dragoman and provisions, &c., on board, and some men, and went up
the Cataract. It was a most amusing affair, and most beautiful and
curious scenery all the way. It is a long rapid of three miles, and
perhaps one mile wide, full of rocky islands and isolated rocks. A
bird’s-eye view hardly shows a free passage, and some of the more
rapid falls are between rocks not forty feet wide--in appearance
not twenty. Although they do not drag the boats up perpendicular
falls of three or four feet, as the travellers’ books tell you,
they really do drag the boats up rushes of water which, until I had
seen it, and had then calculated the power required, I should
imprudently have said could not be effected. We were dragged up at
one place a gush of water, what might fairly be called a fall of
about three feet, the water rushing past very formidably, and
between rocks seemingly not more than wide enough to let our boat
pass, and this only by some thirty-five men at three or four ropes,
the men standing in the water and on the rocks in all directions,
shouting, plunging into the water, swimming across the top or
bottom of the fall, just as they wanted, then getting under the
boat to push it off rocks, all with an immense expenditure of noise
and apparent confusion and want of plan, yet on the whole properly
and successfully. We were probably twenty or thirty minutes getting
up this one, sometimes bumping hard on one rock, sometimes on
another, and jammed hard first on one side and then on the other,
the boat all the time on the fall with ropes all strained,
sometimes going up a foot or two, sometimes losing it, till at last
we crept to the top, and sailed quietly on in a perfectly smooth
lake. These efforts up the different falls had been going on for
nearly eight hours, and the relief from noise was delicious. We
selected a quiet spot under the temples of Philæ.... Our
poultry-yard is on the sandbank, where fowls, pigeons, and turkeys
are walking about loose, and, like all animals in this country,
perfectly tame. Yes, they walk up and catch a pigeon to be killed
when you like. In the midst of these and of the small birds which
always walk and fly about us, have been walking for hours this
morning three or four large eagles, who, with the politeness
peculiar to animals here, pay no attention to our fowls, nor do
they to the eagles. But here I am entering on the anomalies and
contradictions of Egypt, which would fill volumes.
After leaving Egypt, Mr. Brunel went to Naples and Rome, where he spent
Easter, and he returned to England in the middle of May.
When abroad, Mr. Brunel made sight-seeing a pleasure rather than a
business; thus in Egypt he preferred to visit frequently the same
places, and rather to enjoy that which he knew gave him pleasure, than
to hurry about with the object of seeing all that was to be seen. At
Philæ he stopped more than a week, and at Thebes he spent more time in a
small outlying temple near Karnac than in the great ruin itself. So also
at Rome he went frequently to the Colosseum, and he spent many hours in
the interior of St. Peter’s.
Shortly after his return to England he went to Plymouth, and over the
Saltash bridge and other parts of the Cornwall Railway, which had been
opened during his absence abroad.
Although it had by this time become certain that the disease under which
he laboured had assumed a fatal character, he continued to give
unremitting attention to his various professional duties; and in order
to be nearer the ‘Great Eastern,’ he took a house at Sydenham, and
removed there with his family in the beginning of August.
Almost every day he went to the great ship and superintended the
preparations for getting her to sea. She was advertised to sail on
September 6, and Mr. Brunel had intended going round in her to Weymouth.
He was on board early on the morning of the 5th, and his memorandum book
has, under that date, an entry of some unfinished work which had to be
looked after. Towards midday he felt symptoms of failing power, and went
home to his house in Duke Street, when it became evident that he had
been attacked with paralysis.
* * * * *
At one time it seemed possible that he might recover; but on the tenth
day after his seizure, Thursday, September 15, all hope was taken away.
In the afternoon he spoke to those who watched around him, calling them
to him by their names; as evening closed in he gradually sank, and died
at half-past ten, quietly and without pain.
* * * * *
The funeral was on September 20, at the Kensal Green Cemetery.
Along the road leading to the chapel many hundreds of his private and
professional friends, his neighbours among the tradespeople of
Westminster, the Council of the Institution of Civil Engineers, and the
servants of the Great Western Railway Company, had assembled, and, with
his family, followed his body to its place of burial, in the grave of
his father and mother.[198]
It would be improper here to attempt to enter into a general criticism
of Mr. Brunel’s works, or to determine the position which he is entitled
to occupy among civil engineers. That task has yet to be accomplished,
and must be undertaken by those who can claim to be impartial judges. It
has been the object of this book to provide, as far as possible, the
materials on which a just judgment of his career can be based.
But it may be permitted, in conclusion, to place on record the following
testimony to the high position held by Mr. Brunel in the esteem of his
contemporaries.
* * * * *
On November 8, 1859, at the first meeting of the Institution of Civil
Engineers after the death of Mr. Brunel and of Mr. Robert Stephenson,
Mr. Joseph Locke, M.P., the President, rose and said--
‘I cannot permit the occasion of opening a new session to pass without
alluding to the irreparable loss which the Institution has sustained by
the death, during the recess, of its two most honoured and distinguished
members.
‘In the midst of difficulties of no ordinary kind, with an ardour
rarely equalled, and an application both of body and mind almost beyond
the limit of physical endurance, in the full pursuit of a great and
cherished idea, Brunel was suddenly struck down, before he had
accomplished the task which his daring genius had set before him.
‘Following in the footsteps of his distinguished parent, Sir Isambard
Brunel, his early career, even from its commencement, was remarkable for
originality in the conception of the works confided to him. As his
experience increased, his confidence in his own powers augmented; and
the Great Western Railway, with its broad-gauge line, colossal engines,
large carriages, and bold designs of every description, was carried
onward, and ultimately embraced a wide district of the country.
‘The same feeling induced, in steam navigation, the successive
construction of the “Great Western” steamer, the largest vessel of the
time, until superseded by the “Great Britain,” which was in its turn
eclipsed by the “Great Eastern,” the most gigantic experiment of the
age.
‘The Great Ship was Brunel’s peculiar child; he applied himself to it in
a manner which could not fail to command respect; and, if he did not
live to see its final and successful completion, he saw enough, in his
later hours, to sustain him in the belief that his idea would ultimately
become a triumphant reality.
‘The shock which the loss of Brunel created was yet felt, when we were
startled by an announcement that another of our esteemed members had
been summoned from us.[199]
* * * * *
‘It is not my intention at this time to give even an outline of the
works achieved by our two departed friends. Their lives and labours,
however, are before us; and it will be our own fault if we fail to draw
from them useful lessons for our own guidance. Man is not perfect, and
it is not to be expected that he should be always successful; and, as in
the midst of success we sometimes learn great truths before unknown to
us, so also we often discover in failure the causes which frustrate our
best directed efforts. Our two friends may probably form no exception to
the general rule; but, judging by the position they had each secured,
and by the universal respect and sympathy which the public has
manifested for their loss, and remembering the brilliant ingenuity of
argument, as well as the more homely appeals to their own long
experience, often heard in this hall, we are well assured that they have
not laboured in vain.
‘We, at least, who are benefited by their successes, who feel that our
Institution has reason to be proud of its association with such names as
Brunel and Stephenson, have a duty to perform; and that duty is, to
honour their memory and emulate their example.’
APPENDIX I.
(_See Chapter V. on the Broad Gauge, p. 99._)
_Report to the Board of Directors of the Great Western Railway Company._
August 1838.
GENTLEMEN,--As the endeavour to obtain the opinions and reports of Mr.
Walker, Mr. Stephenson, and Mr. Wood, prior to the next half-yearly
meeting, has not been successful, I am anxious to record more fully than
I have previously done, and to combine them into one report, my own
views and opinions upon the success of the several plans which have been
adopted at my recommendation in the formation and in the working of our
line; and in justice to myself and to these plans, and indeed to enable
others to arrive at any just conclusion as to the result which has been
attained, or as to the probable ultimate success or advantages of the
system, it is necessary that I should enter very fully, I fear even
tediously, into a recapitulation of the circumstances, peculiar to this
railway, which led to the consideration and the adoption of these plans,
which some call innovations and wide deviations from the results of past
experience, but the majority of which I will undertake to show are
merely adaptations of those plans to our particular circumstances.
It will be necessary also that I should refer to all the numerous
difficulties which we have had to encounter, which have necessarily
prevented the perfect working of these plans in the first instance, but
which have been overcome, or which are gradually and successively
diminishing; and, finally, I am prepared to show that, notwithstanding
the novelty of the circumstances, and the difficulties and delays which
at the outset invariably attend any alteration, however necessary, or
however desirable, from the accustomed mode of proceeding, and
notwithstanding the violent prejudices excited against us, and the
increased difficulties caused by these prejudices, the result is still
such as to justify the attempt which has been made, and to show that in
the main features, if not in all the details, the system hitherto
followed is good, and ought to be pursued.
The peculiarity of the circumstances of this railway, to which I would
more particularly refer, and which have frequently been mentioned,
consists in the unusually favourable gradients and curves which we have
been able to obtain. With the capability of carrying the line upwards of
fifty miles out of London on almost a dead level, and without any
objectionable curve, and having beyond this, and for the whole distance
to Bristol, excellent gradients, it was thought that unusually high
speed might easily be attained, and that the very large extent of
passenger traffic which such a line would certainly command would ensure
a return for any advantages which could be offered to the public, either
in increased speed or increased accommodations. With this view every
possible attention was paid to the improvement of the line as originally
laid down in the parliamentary plans. We ultimately succeeded in
determining a maximum gradient of 4 feet per mile, which could be
maintained for the unusual distance, before mentioned, of upwards of
fifty miles from London, and also between Bristol and Bath,
comprehending those parts of the line on which the principal portion of
the passenger traffic will be carried. The attainment of high speed
appeared to involve the question of the width of gauge, and on this
point accordingly I expressed my opinion at a very early period.
It has been asserted that 4 feet 8 inches, the width adopted on the
Liverpool and Manchester Railway, is exactly the proper width for all
railways, and that to adopt any other dimension is to deviate from a
positive rule which experience has proved correct; but such an assertion
can be maintained by no reasoning. Admitting, for the sake of argument,
that, under the particular circumstances in which it has been tried, 4
feet 8 inches has been proved the best possible dimension, the question
would still remain--What are the best dimensions under the
circumstances?
Although a breadth of 4 feet 8 inches has been found to create a certain
resistance on curves of a certain radius, a greater breadth would
produce only the same resistance on curves of greater radius. If
carriages and engines, and more particularly if wheels and axles of a
certain weight, have not been found inconvenient upon one railway,
greater weights may be employed and the same results obtained on a
railway with better gradients. To adopt a gauge of the same number of
inches on the Great Western Railway as on the Grand Junction Railway,
would in fact amount practically to the use of a different gauge in
similar railways. The gauge which is well adapted to the one is not well
adapted to the other, unless, indeed, some mysterious cause exists which
has never yet been explained for the empirical law which would fix the
gauge under all circumstances.
Fortunately this no longer requires to be argued, as too many
authorities may now be quoted in support of a very considerable
deviation from this prescribed width, and in every case this change has
been an increase. I take it for granted that, in determining the
dimensions in each case, due regard has been had to the curves and
gradients of the line, which ought to form a most essential, if not the
principal, condition.
In the Report of the Commissioners upon Irish Railways, the arguments
are identically the same with those which I used when first addressing
you on the subject in my Report of October 1835. The mechanical
advantage to be gained by increasing the diameter of the carriage-wheels
is pointed out, the necessity, to attain this, of increasing the width
of way, the dimensions of the bridges, tunnels, and other principal
works, not being materially affected by this; but, on the other hand,
the circumstance which limits this increase being the curves on the
line, and the increased proportional resistance on inclinations (and on
this account it is stated to be almost solely applicable to very level
lines); and, lastly, the increased expense, which could be justified
only by a great traffic.
The whole is clearly argued in a general point of view, and then applied
to the particular case, and the result of this application is the
recommendation of the adoption of 6 feet 2 inches on the Irish railways.
Thus, an increase in the breadth of way to attain one particular
object--viz. the capability of increasing the diameter of the
carriage-wheels without raising the bodies of the carriages--is admitted
to be most desirable, but is limited by certain circumstances, namely,
the gradients and curves of the line, and the extent of traffic.
Every argument here adduced, and every calculation made, would tend to
the adoption of about 7 feet on the Great Western Railway.
The gradients of the lines laid down by the Irish Commission are
considerably steeper than those of the London and Birmingham Railway,
and four and five times the inclination of those on the Great Western
Railway; the curves are by no means of very large radius, and indeed the
Commissioners, after fixing the gauge of 6 feet 2 inches, express their
opinion, that upon examination into the question of curves, with a view
to economy, they do not find that the effect is so injurious as might
have been anticipated, and imply therefore that curves, generally
considered of small radius on our English lines, are not incompatible
with the 6 feet 2 inch gauge; and, lastly, the traffic, instead of being
unusually large, so as to justify any expense beyond that absolutely
required, is such as to render assistance from Government necessary to
ensure a return for the capital embarked. As compared with this, what
are the circumstances in our case?
The object to be attained is the placing an ordinary coach body, which
is upwards of 6 feet 6 inches in width, between the wheels. This
necessarily involves a gauge of rail of about 6 feet 10½ inches to 6
feet 11 inches, but 7 feet allows of its being done easily; it allows,
moreover, of a different arrangement of the body: it admits all sorts of
carriages, stage-coaches, and carts to be carried between the wheels.
And what are the limits in the case of the Great Western Railway, as
compared to those on Irish railways? Gradients of one-fifth the
inclination, very favourable curves, and probably the largest traffic in
England.
I think it unnecessary to say another word to show that the Irish
Commissioners would have arrived at 7 feet on the Great Western Railway
by exactly the same train of argument that led them to adopt 6 feet 2
inches in the case then before them.
All these arguments were advanced by me in my first Report to you, and
the subject was well considered. The circumstance of the Great Western
Railway, and other principal railways likely to extend beyond it, having
no connection with other lines then made, leaving us free from any
prescribed dimension, the 7-feet gauge was ultimately determined upon.
Many objections were certainly urged against it: the deviation from the
established 4 feet 8 inches was then considered as the abandonment of
the principle: this, however, was a mere assertion, unsupported even by
plausible argument, and was gradually disused; but objections were still
urged, that the original cost of construction of all the works connected
with the formation of the line must be greatly increased; that the
carriages must be so much stronger; that they would be proportionally
heavier; that they would not run round the curves, and would be more
liable to run off the rails; and particularly, that the increased length
of the axles would render them liable to be broken: and these objections
were not advanced as difficulties which, as existing in all railways,
might be somewhat increased by the increase of gauge, but as peculiar to
this, and fatal to the system.
With regard to the first objection, namely, the increased cost in the
original construction of the line, if there be any, it is a question of
calculation which is easily estimated, and was so estimated before the
increased gauge was determined upon. Here, however, preconceived
opinions have been allowed weight in lieu of arguments and calculations;
cause and effect are mixed up, and without much consideration it was
assumed at once that an increased gauge necessarily involved increased
width of way, and dimensions of bridges, tunnels, &c.
Yet such is not the case within the limits we are now treating of: a
7-feet rail requires no wider bridge or tunnel than a 5-feet; the
breadth is governed by a maximum width allowed for a loaded waggon, or
the largest load to be carried on the railway, and the clear space to be
allowed on either side beyond this.
On the Manchester and Liverpool Railway this total breadth is only 9
feet 10 inches, and the bridge and viaducts need only have been twice
this, or 19 feet 8 inches; 9 feet 10 inches was found, however, rather
too small, and in the London and Birmingham, with the same width of way,
this was increased to 11 feet by widening the interval between the two
rails.
In the space of 11 feet, allowed for each rail, a 7-feet gauge might be
placed just as well as a 5-feet, leaving the bridges, tunnels, and
viaducts exactly the same; but 11 feet was thought by some still too
narrow: and when it is remembered that this barely allows a width of 10
feet for loads, whether of cotton, wool, agricultural produce, or other
light goods, and which are liable also to be displaced in travelling, 13
feet (which has been fixed upon in the Great Western Railway, and which
limits the maximum breadth, under any circumstances, to about 12 feet)
will not be found excessive.
It is this which makes the minimum width, actually required under
bridges and tunnels, 26 feet instead of 22 feet, and not the increased
gauge.
The earthwork is slightly affected by the gauge, but only to the extent
of 2 feet on the embankment, and not quite so much in the cuttings; but
what, in practice, has been the result? The bridges over the railway on
the London and Birmingham are 30 feet, and the width of viaducts 28
feet; on the Great Western Railway they are both 30 feet; no great
expense is therefore incurred on these items, and certainly a very small
one compared to the increased space gained, which, as I have stated, is
from 10 to 12 feet. In the tunnels exists the greatest difference; on
the London and Birmingham Railway, which I refer to as being the best
and most analogous case to that of the Great Western Railway, the
tunnels are 24 feet wide. On the Great Western Railway the constant
width of 30 feet is maintained, more with a view of diminishing the
objections to tunnels, and maintaining the same minimum space which
hereafter may form a limit to the size and form of everything carried on
the railway, than from such a width being absolutely necessary.
Without pretending to find fault with the dimensions fixed, and which
have, no doubt, been well considered, upon the works on other lines, I
may state that the principle which has governed has been to fix the
minimum width, and to make all the works the same, considering it
unnecessary to have a greater width between the parapet walls of a
viaduct, which admits of being altered, than between the sides of a
tunnel which cannot be altered.
The embankments on the London and Birmingham Railway are 26 feet, on the
Great Western 30 feet, making an excess of about six and a half per
cent. on the actual quantity of earthwork.
The difference in the quantity of land required is under half an acre to
a mile. On the whole, the increased dimensions from 10 to 12 feet will
not cause any average increased expense in the construction of the
works, and purchase of land, of above seven per cent.--eight per cent.
having originally been assumed in my Report in 1835 as the excess to be
provided for.
With respect to the weight of the carriages, although we have wheels of
4 feet diameter, instead of 3 feet, which, of course, involves an
increased weight quite independent of the increase of width, and
although the space allowed for each passenger is a trifle more, and the
height of the body greater, yet the gross weight per passenger is
somewhat less.
Tons cwt. qrs. lbs.
A Birmingham first-class coach weighs 3 17 2 0
Which with 18 passengers at 15 to the ton 1 4 0 0
----------------
5 1 2 0
Or 631 lbs. per passenger ================
A Great Western first-class weighs 4 14 0 0
And with 24 passengers 1 12 0 0
----------------
6 6 0 0
Or 588 lbs. per passenger ================
And our 6-wheeled first-class 6 11 0 0
With 32 passengers 2 2 2 0
----------------
8 13 2 0
Or 600 lbs. per passenger ================
Being an average of 594 lbs. on the two carriages.
This saving of weight does not arise from the increased width, and is
notwithstanding the increased strength of the framing and the increased
diameter and weight of the wheels; I have not weighed our second-class
open carriages, but I should think the same proportion would exist.
As to the breaking of axles or running off the line, the practical
result has been that, from some cause or other, we have been almost
perfectly free from those very objections which have been felt so
seriously on some other lines. Far from breaking any engine axles, not
even a single cranked axle has been strained, although the engines have
been subjected to rather severe trials. One of our largest having, a
short time back, been sent along the line at night, when it was not
expected, came in collision with some ballast waggons, and was thrown
off the line nearly 6 feet; none of the axles were bent, or even
strained in the least, although the front of the carriage, a piece of
oak of very large scantling, was shattered. After ten weeks’ running,
one solitary instance has occurred of a carriage in a train getting off
the line and dragging another with it, and which was not discovered till
after running a mile and a half. As the carriage was in the middle of
the train, and one end of the axle was thrown completely out of the axle
guard, there must evidently have been some extraordinary cause--possibly
a plank thrown across the railway by a blow from the carriage which
preceded, and which might have produced the same effect on any railway;
and at any rate it was a strong trial to the axle, which was not broken,
but merely restored to its place, and the carriage sent on to London.
The same mode of reasoning which has by some been used in favour of the
4 feet 8 inches gauge, if applied here, would prove that long axles are
stronger than short, and wide rails best adapted for curves. All that I
think proved, however, is this--that the increased tendency of the axles
to break, or of the wheels to run off the rails, is so slight that it is
more than counterbalanced by the increased steadiness from the width of
the base, and the absence of those violent strains which arise from
irregularity on the gauge and the harshness of the ordinary construction
of rails. In fact, not one of the objections originally urged against
the practical working of the wide gauge has been found to exist, while
the object sought for is obtained, namely, the capability of increasing
at any future period the diameter of the wheels, which cannot be done,
however desirable it may hereafter be found, with the old width of rail.
This may be said to be only prospective; but, in the meantime,
contingent advantages are sensibly felt in the increased lateral
steadiness of the carriages and engines, and the greater space which is
afforded for the works of the locomotives. And here I wish particularly
to call your attention to the fact that this prospective advantage--this
absence of a most inconvenient limit to the reduction of the friction,
which, with our gradients, forms four-fifths or eighty per cent. of the
total resistance--was the object sought for, and that, at the time of
recommending it, I expressly stated as follows:--‘I am not by any means
prepared at present to recommend any particular size of wheel, or even
any great increase of the present dimensions. I believe they _will_ be
materially increased; but my great object would be in every possible way
to render each part _capable_ of improvement, and to remove what appears
an obstacle to any great progress in such a very important point as the
diameter of the wheels, upon which the resistance, which governs the
cost of transport and the speed that may be obtained, so materially
depends.’
These advantages were considered important by you, they are now
considered so by many others; and certainly everything which has
occurred in the practical working of the line confirms me in my
conviction that we have secured a most valuable power to the Great
Western Railway, and that it would be folly to abandon it.
The next point I shall consider is the construction of the engines, the
modifications in which, necessary to adapt them to higher speeds than
usual, have, like the increased width of gauge, been condemned as
innovations.
I shall not attempt to argue with those who consider any increase of
speed unnecessary. The public will always prefer that conveyance which
is most perfect, and speed within reasonable limits is a material
ingredient in perfection in travelling.
A rate of thirty-five to forty miles an hour is not unfrequently
attained at present on other railways in descending planes, or with
light loads on a level, and is found practically to be attended with no
inconvenience. To maintain such a speed with regularity on a level line,
with moderate loads, is therefore quite practicable, and unquestionably
desirable. With this view the engines were constructed, but nothing new
was required or recommended by me.
A certain velocity of the piston is considered the most advantageous.
The engines intended for slow speeds have always had the driving wheels
small in proportion to the length of stroke of the piston. The faster
engines have had a different proportion; the wheels have been larger, or
the strokes of the piston shorter. From the somewhat clamorous
objections raised against the large wheels, and the construction of the
Great Western Railway engines, and the opinions rather freely expressed
of my judgment in directing this construction, it would naturally be
supposed that some established principle had been departed from, and
that I had recommended this departure.
The facts are, that a certain velocity of piston being found most
advantageous, I fixed this velocity, so that the engines should be
adapted to run thirty-five miles an hour, and capable of running
forty--as the Manchester and Liverpool Railway engines are best
calculated for twenty to twenty-five, but capable of running easily up
to thirty and thirty-five miles per hour; and fixing also the load which
the engine was to be capable of drawing, I left the form of construction
and the proportions entirely to the manufacturers, stipulating merely
that they should submit detail drawings to me for my approval. This was
the substance of the circular, which, with your sanction, was sent to
several of the most experienced manufacturers. Most of these
manufacturers, of their own accord, and without previous communication
with me, adopted the large wheels, as a necessary consequence of the
speed required. The recommendation coming from such quarters, there can
be no necessity for defending my opinion in its favour; neither have I
now the slightest doubt of its correctness. As it has been supposed that
the manufacturers may have been compelled or induced by me to adopt
certain modes of construction, or certain dimensions, in other parts by
a specification--a practice which has been adopted on some lines--and
that these restrictions may have embarrassed them, I should wish to take
this opportunity to state distinctly that such is not the case. I have
indeed strongly recommended to their consideration the advantages of
having very large and well-formed steam passages, which generally they
have adopted, and with good results; and with this single exception, if
it can be considered one, they have been left unfettered by me (perhaps
too much so) and uninfluenced, except indeed by the prejudices and fears
of those by whom they have been surrounded, which have by no means
diminished the difficulties I have had to contend with.
The principal proportions of these engines being those which have been
recommended by the most able experimentalists and writers, and these
having been adopted by the most experienced makers, it is difficult to
understand who can constitute themselves objectors, or what can be their
objections.
Even if these engines had not been found effective, at least it must be
admitted that the best and most liberal means had been adopted to
procure them; but I am far from asking such an admission. The engines,
I think, have proved to be well adapted to the particular task for which
they were calculated--namely, high speeds--but circumstances prevent
their being beneficially applied to this purpose at present, and they
are, therefore, working under great disadvantages. An engine constructed
expressly for a high velocity cannot, of course, be well adapted to
exert great power at a low speed; neither can it be well adapted for
stopping frequently and regaining its speed. But such was not the
intention when these engines were made, neither will it be the case when
the arrangements on the line are complete; in the meantime, our average
rate of travelling is much greater than it was either on the Grand
Junction or the Birmingham Railway within the same period of the
opening. I have but one serious objection to make to our present
engines, and for this, strange as it may seem, I feel that we are mainly
indebted to those who have been most loud in their complaints--I refer
to the unnecessary weight of the engines. There is nothing in the wide
gauge which involves any considerable increased weight in the engine. An
engine of the same power and capacity for speed, whether for a 4-feet
8-inch rail, or for a 7-feet rail, will have identically the same
boiler, the same fire-box, the same cylinder and piston, and other
working gear, the same side frames, and the same wheels; the axles and
the cross-framing will alone differ, and upon these alone need there be
any increase; but, if these were doubled in weight, the difference upon
the whole engine would be immaterial. But the repeated assertion,
frequently professing to come from experienced authorities, and repeated
until it was supposed to be proved, that the increased gauge must
require increased strength and great power, was not without its indirect
effect upon the manufacturers. Unnecessary dimensions have been given to
many parts, and the weight thereby increased--rather tending, as I
believe, to diminish than to add to the strength of the whole. I thought
then, and I believe now, that it would have been unwise in this case to
have resisted the general opinion, and taken upon myself the
responsibility which belonged to the manufacturers; but I need not now
hesitate to say that a very considerable reduction may be effected, and
that no such unusual precautions are necessary to meet these anticipated
strains and resistances--such being, in fact, imaginary. It cannot
surprise anybody that, under such circumstances, attention was more
occupied in endeavouring to meet these imaginary prejudiced objections,
than in boldly taking advantage of the new circumstances, and that a
piece of machinery constructed under such disadvantages was not likely
to be a fair sample of what might be done. I am happy to say, however,
that the result of the trials that have been made has entirely destroyed
all credit in these alarmists with the manufacturer, and that we may
hope in future to have the benefits of the free exercise of the
intelligence and practical knowledge of engine-manufacturers.
The mode of laying the rails is the next point which I shall consider.
It may appear strange that I should again in this case disclaim having
attempted anything perfectly new; yet regard to truth compels me to do
so. I have recommended, in the case of the Great Western, the principle
of a continuous bearing of timber under the rail, instead of isolated
supports--an old system recently revived, and as such I described it in
my Report of January 1836; the result of many hundred miles laid in this
manner in America, and of some detached portions of railways in England,
was quite sufficient to prove that the system was attended with many
advantages; but since we first adopted it these proofs have been
multiplied--there need now be no apprehension. There are railways in
full work, upon which the experiment has been tried sufficiently to
prove beyond doubt, to those willing to be convinced, that a permanent
way in continuous bearings of wood may be constructed, in which the
motion will be much smoother, the noise less, and consequently--for they
are effects produced by the same cause--the wear and tear of the
machinery much less. Such a plan is certainly best adapted for high
speeds, and this is the system recommended by me and adopted on our
road. There are, no doubt, different modes of construction, and that
which I have adopted as an improvement upon others may, on the contrary,
be attended with disadvantages. For the system I will strenuously
contend.
But I should be sorry to enter with any such determined feeling into a
discussion of the merits of the particular mode of construction. I would
refer to my last Report for the reasons which influenced me, and the
objects I had in view in introducing the piling; that part which had
been made under my own eye answered fully all my expectations. Here the
piles did answer their purpose, and no inconvenience resulted from their
use. The difficulties which we have since encountered, the bad state in
which the line was for a considerable time, and which is only recently
improved, have undoubtedly been aggravated, if not caused, by these
piles; but not, as I believe, from a defect in the principle as applied
in our case, where the line is mostly in cutting, or on the surface, but
from defective execution; for, notwithstanding the determination to
allow sufficient time for this most important operation, yet, to make up
for previous delays and loss of time, it became necessary at last to
force forward the work more rapidly than was at all consistent with due
care in the execution; and during the whole of this period I was most
unfortunately prevented by a serious accident from even seeing the work
almost until the day of opening, when I ought to have personally
superintended the whole. I do not mean that the work was neglected by
those whose duty it was to supply my place--far from it; but in such a
case, a new work cannot be properly directed except under the eye of the
master. Following exactly the plan which had succeeded on the first
piece completed, several serious faults were committed. A much greater
density and firmness of packing is required than was previously
supposed; the mode of packing adopted, and the material selected, in the
first instance, have proved defective elsewhere; and over a great extent
in the line, particularly in the clay cuttings, and where the work was
at last most hurried, it has been badly executed. But many parts have
stood well from the commencement; others are fast improving; and I have
the satisfaction, although a very painful one, of seeing that if, in the
first instance, a foundation of coarse gravel had been everywhere well
rammed in before the timbers had been laid, and the packing formed upon
this, we should, from the outset, have obtained as solid a road as we
have now over a great part of the line. What we have been able to effect
since the opening of the line has necessarily been a slow, expensive,
and laborious operation. We have been compelled to open the ground, and
excavate it to a depth of 18 inches under the longitudinal timbers, and
this without interrupting the traffic: to remove the whole of the
material thus obtained from off the line, and to replace it by coarse
ballast; and not having the means of sufficiently consolidating this
ballast by ramming while the timber is in its place, the packing has to
be repeated once or twice after it has been compressed by the passing of
the trains. This new packing, however, does stand, and in a few weeks I
expect the line will be in a very different state from that in which it
has been, or indeed now is. From what I have described as the result
which can now be, and might have been, obtained from the commencement,
it will be inferred that I am disposed still to defend the system of
piling. I certainly could not abandon it from conviction of its
inefficiency, for I see proofs of the contrary; and I feel that under
similar circumstances I could now prevent the mischief which has
occurred. Upon that portion of the line where the permanent way must
next be formed, piling could not be resorted to, the ground being a
solid hard chalk for many miles. I had intended, however, recommending
the same principle, but in a different form, holding down the
longitudinals by small iron rods driven into the chalk; but the same
objection could not exist, because the chalk cannot yield under the
timbers like clay, or even gravel. But I should wish most anxiously to
avoid anything like an obstinate adherence to a plan, if the object
which I believe essential can be obtained by other means, particularly
when, that plan being my own, I may be somewhat prejudiced in its
favour. I find that the system of piling involves considerable expenses
in the first construction, and requires perhaps too great a perfection
in the whole work, and that if the whole or a part of this cost were
expended in increased scantling of timber and weight of metal, that a
very solid continuous rail would be formed.
For this as a principle, as for the width of gauge, I am prepared to
contend, and to stand or fall by it, believing it to be a most essential
improvement, where high speeds are to be obtained. I strongly urge upon
you not to hesitate upon these two main points, which, combined with
what may be termed the natural advantages of the line, will eventually
secure to you a superiority which, under other circumstances, cannot be
obtained.
As regards the expense of forming the permanent way on this principle, I
am quite prepared to maintain what I have on a former occasion advanced:
that even on the system which we have adopted between London and
Maidenhead, the total cost does not materially exceed that of a
well-constructed line with stone blocks. I did not make in the outset an
exact estimate of the cost of either mode; I was unable to obtain the
cost which has actually been incurred on other lines; but a comparative
estimate was made, and the result of that comparison led me to state
that the one might exceed the other by 500_l._ a mile. The actual cost
of our permanent way appears, by the detailed account which has been
made out, to have been above 9,000_l._, including expenses of
under-draining and forming the surfaces which cannot be included in the
cost given in other cases, because that drainage (although I believe
generally forming part of the plan) is not yet constructed. This sum
includes the sidings at the stations, switches, joints, and other
contingencies, and also the expenses incurred during the first month of
working the line, and which, as I have before stated, consisted in
removing and replacing work which had been improperly executed. These
items will make a considerable reduction; and besides these, larger
reductions may be effected in parts of the work which were new, and,
from the circumstances naturally attending a first attempt, were not so
economically conducted as they might be, or indeed, as they were towards
the close of the works, when the different parts were let by contract.
Taking the prices at which the work was latterly actually executed,
8,000_l._ per mile would be a liberal allowance for our future
proceeding, even adopting the same system; and with a modified system,
such as that suggested of simple longitudinal bearers of large
scantling, and a rail of fifty-four pounds per yard, at the present high
price of iron, the cost, calculated upon our actual past expenditure,
would not exceed 7,400_l._ per mile. This, I am aware, is a larger sum
than that which has usually been assumed as the cost of the permanent
way. I cannot prove that others have cost more, or even so much as this,
as I have nothing but the published accounts to refer to; but this I can
state, and prove if necessary, that rails and blocks, such as are now
being adopted on the Manchester and Liverpool Railway, would upon our
line cost at least as much.
The prime cost of rails and chairs delivered on the line would alone
amount to half the money; and nothing is, perhaps, more certain than
that the experience of other lines within the last two or three years
has proved that this part of the construction of a railway is
unavoidably much more expensive than was ever calculated for at the time
our estimates were made.
I am, gentlemen, your obedient servant,
(Signed) I. K. BRUNEL.
APPENDIX II.
(_See Chapter IX. on the ‘Great Britain’ Steam-Ship, p. 254._)
_Report to the Directors of the Great Western Steam-Ship Company._
October 1840.
GENTLEMEN,--I have now the pleasure to lay before you the result of the
different experiments which I have made, and of the best consideration I
have been enabled to give to the subject of the screw propeller.
The observations which I have to make are naturally divided under two
principal heads, namely: first, the simple question of the applicability
and efficiency of the screw considered merely as a means of propelling a
vessel, compared with the ordinary paddlewheel; and, secondly, the
general advantages or disadvantages attending its use.
The consideration of the comparative efficiency of the screw as a means
of propelling, of course embraces the whole question, not merely of the
effect produced, but also that of the proportionate power absorbed in
producing that effect.
With respect to the mere effect of a screw, the performance of the
‘Archimedes’ has proved, in a satisfactory and undeniable manner, that a
screw acting against the water with a surface even much smaller than
that offered by the paddle-boards of a well-proportioned paddlewheel,
will propel the ship at a very fair speed, but at what expense of power
this effect has been produced is not so evident.
I shall first examine into the principal cause of what amounts
practically to a loss of power, and which is common in a greater or less
degree to all modes of propelling a vessel by exerting a pressure
against the water as against a fixed point.
The resistance, whether to the surface of a screw, or of a paddle-board,
or of the blade of an oar, or any other propelling body, offered by the
fluid against which it acts, is of course not perfect, and there is a
certain amount of yielding, commonly called the slip, of the
paddlewheel; the amount thus slipped causes a considerable waste of
power, inasmuch as the full power of the engine is expended through the
entire space passed over by the paddles or other propelling surface,
while the useful effect produced is only equal to the same power
expended over the space through which the vessel passes: this loss
frequently amounts to one-quarter, and even one-third, of the whole
power employed. To investigate theoretically the amount of slip due to
any given form and quantity of surface, involves much more complicated
calculations than have generally been applied, and would indeed require
data which we hardly possess; but fortunately we have had the means of
making experiments, the results of which enable us to determine the
comparative slip of the paddle and of the screw, with sufficient
accuracy for all practical purposes.
The screw in use on board the ‘Archimedes’ is 5 feet 9 inches diameter,
with a pitch of 8 feet--that is to say, in making one revolution the
thread of the screw advances 8 feet; the area of the screw, considered
as a disc of the same diameter, or the extent of the surface of water
which is acted upon in the direction of the axis of the vessel, is
therefore about 26 feet, without deducting the section of the
shaft-bearing, &c. The midship section of the vessel when I experimented
upon her was, according to Mr. Patterson’s estimate, 122 feet; the ratio
of the resisting surface to the midship section being therefore as 1 to
4·7, which is a small proportion; and the form of the vessel is by no
means peculiarly good as a steamboat. This proportion of propelling
surface to midship section is much smaller--that is, the area of the
screw is much less in proportion to the size of the vessel than is the
area of paddle-boards immersed in steamboats generally.
The average paddle-board immersed and really effective is rather
difficult to estimate, as allowances must be made for the disturbance of
the water, when the wheel is in motion; but this average in the ‘Great
Western’ measured perpendicularly--that is, allowing for the obliquity
of the paddle--cannot be less than 180 to 200 feet, say only 180, while
the midship section averages about 462 feet; the surface of paddle is
therefore about 1/2·56 of the midship section.
I will now give the comparative effects of these different propelling
surfaces in these two cases.
I have made very accurate experiments upon the comparative rate of the
‘Archimedes,’ and of the space passed through by the screw, and was
enabled to determine this ratio with great certainty.
The average of a number of trials gave the following results:
Rate of ship, 50,867 feet per hour, or about 8⅓ knots.
Space passed through by screw due to the number of revolutions, 65,685
feet.
The average rate of vessel being to that of screw therefore as 1 to
1·2913.
In the performances of the ‘Great Western,’ upon an average of 20
voyages the ratio has been as 1 to 1·2997; but, separating from these 20
such voyages as were unusually short or long, and taking only such as,
occupying 14, 15, or 16 days, may be considered as giving a fair average
of the speed of the ship when not adversely affected by the wind or
heavy seas, the average of these 13 voyages give 1 to 1·283; and leaving
out again those of 16 days, and taking only 8 voyages of 14 and 15 days,
the average gives a ratio of 1 to 1·27187.
Of these, 5 voyages of 15 days give 1 to 1·29077,
and 3 " 14 " 1 to 1·23901.
The last three, however, were short passages and homeward, when the
currents and winds have been in favour, and consequently we may safely
say that the ratio must be above 1 to 1·239; and after making every
allowance for the effect of swell and other impediments (the experiments
upon the ‘Archimedes’ being made in smooth water), the average of the 8
(5 of which were homeward voyages with favourable current and wind and
the vessel in good trim), giving a ratio of 1 to 1·27, may be taken as a
fair average.
The comparison between the ‘Archimedes’ and the ‘Great Western’ will
therefore stand thus--
Area of Propelling Difference of Speed of
Surface, the Midship Vessel and Propelling
Section being 1·0. Surface, or amount
of Slip, the ratio
of Vessel being 1·0.
‘Archimedes,’ screw 0·203 0·2913
‘Great Western,’ paddle 0·391 0·2708
Showing an amount of slip in the ‘Great Western’ very nearly equal to
that of the ‘Archimedes,’ while the ratio of the propelling surface to
the midship section in the case of the screw is little more than half
that of the paddle-boards in the ‘Great Western.’
In taking the average of the eight voyages of the ‘Great Western’ with
favourable winds as I have done, I believe I have made full allowance
for the different circumstances of smooth water and sea; but there is
ample room in the above comparison to make even greater allowance for
these circumstances, and still to leave a result which would prove that
with _similar areas_ the screw would meet with at least equal, if not a
greater resistance, and consequently will slip as little or less than
the ordinary paddle-board.
I subjoin a table also, taken from a well-known work on the steam-engine
(Tredgold’s), of the slip of a number of vessels, of which in every case
the surface of paddle immersed is far greater in proportion to the
midship section than that of the screw in the ‘Archimedes.’
_Rate of Paddle, that of Ship being_ 1.
Medea 1·595
Flamer 1·483
Firebrand 1·501
Columbine 1·529
Salamander 1·200[200]
Dee 1·366
Firefly 1·364
Firebrand, as altered 1·295
Phito 1·215
Monarch 1·323
Magnet 1·310
Meteor 1·490
Carron 1·287
Average 1·381
Great Western 1·27
Archimedes 1·29
This list shows that the result in the ‘Great Western,’ with which ship
I have made the comparison, is in itself a favourable one, and that
compared with many others the ‘Archimedes’ would stand much better.
This apparent superiority of the screw over the paddle as regards the
resistance offered to it by the water may at first appear startling, but
there is a great mistake committed in assuming that the action of the
screw is a very oblique action, tending rather to drive the water
laterally with a rotatory motion than to push it steadily backwards.
Having witnessed and carefully observed the degree and the nature of the
disturbance in the water caused by the screw, and comparing this with
the violent displacement of the water by the action of paddle-boards,
even under the most favourable circumstances, I no longer feel
surprised.
The mass of water pushed backwards by the action of the screw appears to
be very large, spreading from the screw probably in the form of an
inverted cone, but there is little or no appearance of any rotatory
motion, and the surface of the water is not put into rapid motion as in
the case of the paddlewheel, which may be observed to impart a
considerable velocity to the water, probably for a small depth only, but
over a very large space.
As regards the oblique action also, a great mistake appears to have been
generally made, and very naturally made, by most persons when first
considering the working of the screw. It is generally assumed that the
inclined plane formed by the thread of the screw strikes the particles
of water at that angle and with the velocity of the revolution of the
screw, but it is forgotten that the screw is moving forward with the
ship, and therefore that the angle at which the water is struck by the
plane is diminished by all that much that the ship with the screw
advances--indeed, it is evident that if the ship advanced the whole
amount of the pitch of the screw, the screw, oblique as it appears, and
rapidly as it revolves, would not strike the water at all, but simply
glide through.
The angle at which any given part of the screw does in fact strike the
water is only equal to the difference between the angle to which that
part of the screw is formed and the angle or direction in which it moves
by the compound motion of the revolution of the screw and of the forward
motion of the ship and screw; and, contrary to one’s hastily imbibed
notions of the action of the screw, this angle at which the plane of the
screw is driven against the particles of water, is in such a screw as
that of the ‘Archimedes’ very nearly equal over the greater portion of
the surface, diminishing to nothing at the centre; and the motion
imparted to the water, although perpendicular to the plane of the screw
in point of direction, is small in extent or velocity, being also nearly
the same over the whole surface of the screw, except close to the
centre, where it is infinitely small.
In the ‘Archimedes’ screw, which appears to the eye so oblique, and the
centre part of which would appear to act flat against the water, only
causing it to revolve, the outer circumference being 18 feet and the
slip 1 foot 8 inches, the angle at which this outer edge acts upon the
water is only one in 11½.
The total amount of motion imparted to the water at right angles to the
plane of the screw by one entire revolution even at the outer edge is
not quite equal to the slip, being only 1·67 foot. The rotatory motion
is still less, the total distance to which any particle of water is
displaced laterally, or at right angles to the axis of the ship, by one
entire revolution of the screw being at the outer edge only 0·69 foot,
and the maximum distance being in any screw only equal to half the slip,
and occurring at that part of the screw where the circumference is equal
to the advance of the ship due to one revolution. This maximum of
lateral motion is 0·9 foot, and takes place at 0·99 foot, or about 1
foot from the centre. In this mode of considering the direction at which
the particles of water are acted upon by the plate of the screw I have
taken no notice of the effect of the friction upon the surface of the
screw, which, causing to be carried with it a film of water, will modify
more or less according to the degree of smoothness of the surface the
effect of the screw upon the water; and towards the centre this
friction, however smooth the surface may be made, will gradually become
equal to, and at last greater than, the propelling effect of that part
of the screw; but this defect applies only to a very small portion of
the whole area of the screw, and the absence of any very violent impulse
to the water in a direction approaching to a right angle with the axis
of the vessel, and which has always been assumed as an unavoidable evil
in the screw, will account for the absence I have observed upon of any
apparent rotatory motion.
I would not pretend, however, to advance these circumstances which I
have observed, or these reasonings, as arguments whereon to found an
opinion of the action of the screw, the facts as proved by the
experiments are what I rely upon; but it is satisfactory to be able to
account for the results by circumstances actually observed, and the
reasons which suggest themselves.
The effect of a propelling surface in the form of a screw, and moving at
a certain velocity, as compared with an equal surface moving at the same
velocity but applied in the shape of paddle-boards, having been
ascertained, it remains to determine the comparative power required to
give motion to that surface.
The difficulty of determining this with any degree of accuracy from any
experiments which we could make on board the ‘Archimedes’ was very
great, but considering such results as I could obtain in conjunction
with experiments which I have since made in our own works, and with the
results upon steamboats recorded by others, and of those of experiments
made by Colonel Beaufoy on the resistance of bodies in water, I think we
may arrive at approximate conclusions sufficiently accurate for our
purpose, and which may safely be relied upon.
In the case of the ‘Archimedes’ the engines were certainly not effective
well-working engines, the proportions of the gearing or wheel-work
between the engine and the screw was bad--such that the engine could not
attain its proper speed--the friction of the gearing (which, whether it
be a source of resistance necessarily attending the use of the screw or
not, I shall consider afterwards) was very great, and the surface of the
screw itself, which I had an opportunity of examining out of water, was
so rough as necessarily to create very much more friction than would be
caused by a tolerably smooth metallic surface. With all these sources of
resistance, and under these unfavourable circumstances, the power
calculated for the effective pressure on the piston and without
deduction for friction or other causes, which, for the sake of
distinction hereafter, I shall call the gross power, was about 145
horses, the speed of the vessel being about 8⅓ knots per hour, as
actually measured by the land, and full 9 knots as measured with great
care by heaving the common log, the midship section being, as before
stated, 122 feet, and the lines of the vessel not so good as those of
fast boats; comparing this with the gross power of the ‘Great Western’
engines when propelling that vessel at the same velocity, with the
advantage of better lines and the other advantages arising from greater
dimensions, there does not appear any such discrepancy as to indicate
any loss of power by the use of the screw in the ‘Archimedes’; on the
contrary, the power expended in the ‘Great Western’ is actually as great
as that in the ‘Archimedes,’ as compared with their relative midship
sections--and if any great allowance is to be made for the circumstances
which I have referred to of larger dimensions and better lines, there
would appear to be actually less power expended in proportion to the
dimensions and form of the ‘Archimedes’ than in the ‘Great Western.’
The results obtained with the ‘Great Western,’ which as regards speed
are similar to those of the ‘Archimedes,’ are necessarily taken from
experiments made when she was rather deep, and the speed thereby reduced
to 7·9 knots; but I have compared these with results reduced by
calculations from experiments at higher speeds, and I find them agree
satisfactorily--indeed, at the draft and consequent immersion of paddles
when in this state, I consider the ‘Great Western’ as very nearly at her
best as regards economy of power and effect produced. I should observe
that the particular experiments from which the following calculations
are deduced were made with the ‘Great Western’ in smooth water in the
Severn. I have added also some calculations deduced from data given by
Tredgold as to the performance of the ‘Ruby,’ a good boat with immense
surface of paddle-board.
The comparison stands thus:
+--------------------------------------+---------+-----------+-----+
| | GREAT | |
| | WESTERN | ARCHIMEDES| RUBY|
+--------------------------------------+---------+-----------+-----+
|ACTUAL DIMENSIONS: | | | |
| Midship section | 520 | 122 | 63 |
| Area of board immersed | 230 | --- | 64 |
| Area of a disc of diameter of screw | --- | 26 | -- |
| | | | |
|RELATIVE DIMENSIONS AND POWER: | | | |
| Area of propelling surface, midship | | | |
| section being = 1 | 0·442 | 0·213 |1·016|
| Gross power expended for one | | | |
| square foot of midship section | 1·023 | 1·026 |0·976|
+--------------------------------------+---------+-----------+-----+-
The speed being the same, viz., 7·9 knots, the power expended is as
nearly as possible the same in the three, and equal to one horse-power
gross to one foot of midship section; while the relative propelling
surface in the ‘Archimedes’ is equal to only half that of the ‘Great
Western,’ and one-fifth that of the ‘Ruby.’ This _gross_ horse-power, it
will be observed, is _about_ equal to one-half a nominal horse-power.
I have made several comparisons with recorded observations made on board
the ‘Great Western’ at different times, and with experiments made in
other vessels, and I find the same result; in estimating the powers used
more particularly in some comparisons with the ‘Great Western,’ I have
taken the mean pressure as ascertained on both sides of the piston,
while in the ‘Archimedes’ I only obtained that on the top of the piston,
which appears generally to be the best, and consequently the estimate is
made unfavourably to the ‘Archimedes.’
Such general results are all that I could obtain from the experiments on
board the ‘Archimedes,’ but since that time I have made some experiments
upon the friction of a plate of metal in water, and have compared these
results with the experiments of Colonel Beaufoy, and the conclusion I
have come to is that the power absorbed by friction in a well-made
screw, apart from all question of the means adopted for working it,
would not be such as to interfere with its beneficial application.
The resistance created by the screw itself arises principally from two
sources--the resistance to the cutting edge and the tail-edge, and the
friction of the surface in contact with the water. The amount of the
first may of course be reduced to an unlimited extent by having a fine
edge, and practically such edge ought to be much finer than that of the
screw of the ‘Archimedes.’
The friction upon the surface will of course materially depend upon the
smoothness of that surface, and in the ‘Archimedes’ it was very rough,
the iron being corroded at many places, with exfoliations and small
holes--the corrosion arising apparently from the galvanic effect
produced by the iron and the ship’s copper.
The great number of revolutions required in the screw as compared with
those of the paddlewheel, leads a person to assume, without much
consideration, that a very high velocity is given to the cutting edges
and to the surface of the screw, and consequently that great friction
must be produced--this velocity is not, however, nearly so great as it
at first appears.
In the present screw of the ‘Archimedes’ the velocity of the extreme
point, following its oblique or spiral course, is only about three times
that of the vessel, while the average velocity of either of these knife
edges or of the surface is not twice that of the vessel.
Now without determining what the actual amount of these resistances may
be, we can at once satisfy ourselves that it cannot be very
considerable, by comparing it (which we have the means of doing) with
the resistance caused by the cutwater and any given portion of the
ship’s bottom. The resistance of a knife-edge will be about as the
square of the velocity, and if we assume the surface friction to
increase in the ratio determined by Colonel Beaufoy--namely, at the
1·75th power, or as the 4th root of the 7th power of the velocity--then
the resistance of the knife-edge will be equal to the resistance of a
similar edge of about five and a-half times the length of the diameter
of the screw moving at the same rate as the vessel, and the surface
friction will be equal to that of a piece of the ship’s bottom about six
and five-eighth times the area of the screw--or, in the case of the
‘Archimedes,’ the additional power absorbed by the friction of the screw
would be about equal to that absorbed by the friction of little more
than twice the space of the dead wood which had been cut out to receive
the screw--while the knife-edges would be about equivalent to three
knife-edges immersed in the water, of the same depth as the ship’s stem.
The actual amount of power absorbed in driving the ‘Archimedes’ screw
was probably about twenty horse-power gross, or from ten to twelve
nominal horse-power; but I have no doubt that a screw of similar
diameter and in good condition would not absorb half that power: and
this amount may be still further, and very much reduced, by increasing
the relative size of the screw to that of the ship, and thereby reducing
the slip, and proportionately reducing the number of revolutions
required.
The great extent to which this is capable of being carried will at once
be seen when I state that if the ship’s progress were made to be 7 feet
instead of 6 feet to each revolution of the screw, which a very slight
increase of diameter and pitch of screw would effect, the power absorbed
in driving the screw would be diminished in the ratio of the
6^{2}^{4} √6^{7} to 7^{2}^{4} √7^{7}--that is, as 6-15/4 to 7-15/4, or about
as 3 to 2.
I must repeat here the observation I have previously made, and remind
you that these calculations are not introduced as _proving_, but merely
as _explaining_, that which appears to me proved by the general results
of the experiments on the ‘Archimedes’--namely, that the effect produced
was, considering all the circumstances, fully proportionate to the power
expended, while the experiments and calculations which I have since made
also satisfy me that these results may be very much improved upon.
As regards the first of the two heads under which I stated that I
proposed to consider the subject, namely, the mere efficiency of the
screw as a propeller, I think but one conclusion can be drawn from the
results of the experiments quoted, and that 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.
I limit the comparison to the ordinary paddlewheels of sea-going
steamers, first, because those are the circumstances which _we_ have
alone to consider; and, secondly, because it is _possible_, by
increasing the diameter and breadth of the paddles, which, for the
attainment of an adequate object is practicable to any extent in a mere
river boat, to render the action of the common paddle all but perfect,
and probably more effective than any other propeller.
In considering the advantages and disadvantages likely to attend the use
of the screw propeller, I will, commencing with the latter, consider
such objections as have been advanced by others, as well as those which
may have occurred to myself.
The only objections, however, which I think worth consideration are:--
First. The necessity of a peculiar form of vessel.
Secondly. The situation of the screw under water, and consequently to a
certain extent unseen and inaccessible, and the liability to injury from
its position from grounding or in other ways.
Thirdly. The probability of its being lifted out of water when the ship
pitched deep.
Fourthly. The difficulty of getting up the required number of
revolutions, and the great defects of the mode employed in the
‘Archimedes,’ and the shaking caused by the machinery.
As regards the form of vessel, undoubtedly a shallow boat, intended for
shallow waters, would be very unfit for the application of the screw,
which would probably require a greater depth of water than the whole
draft of the vessel; but I see no defect or difficulty of this
description in the vessel now under consideration, nor can I anticipate
any in any vessel this Company is likely to be interested in; a clean
run is the most essential condition, and I should suppose no ship was
ever built in which this principle of form was carried to a greater
extent than in our new iron ship. Her present form I believe to be
excellent for the screw, and with a very slight dropping of the keel
towards the stern, which can easily be done now without any expense,
assisted by the different trim, which, as I shall presently show, will
be effected by the use of the screw, the required draft of water will be
attained.
It may, perhaps, be as well to mention here, that the diameter of the
screw, if in the same ratio to the midship section as in the
‘Archimedes,’ would be only 12 feet 3 inches, my friend Captain Claxton
having made a mistake upon this point in calculating it at 16 feet, and
that if increased only to 14 feet 4 inches, the diminution referred to
in a former part of my Report of one-third in the power lost in working
the screw would be effected; considering the speed we wish to attain,
probably 15 feet 6 inches would be a good diameter. Upon the whole I
think the vessel is as well fitted for a screw as she is for paddles,
and much better adapted for either than the ‘Archimedes;’ but if
originally intended for a screw, possibly some trifling modification in
the form and construction, principally of the keel near the stern, might
have been introduced which would have rendered the whole a more perfect
job than she would now be if altered--but the absence of this would in
no way lessen the efficiency of the screw, and I cannot think that any
alteration we might now be obliged to make would exceed in cost the sum
of 200_l_.
Secondly, the inaccessibility of the screw and liability to damage; this
appears to me the objection most plausible, but I cannot say that I
attach much weight to it, particularly in the case of a vessel intended
for long voyages and across the ocean. During the whole passage in deep
water I consider the screw far less exposed to injury than a
paddlewheel, and that the chances of injury are so remote that even if
it were quite inaccessible it would still be altogether safer than
paddles, which are so much exposed; but it is by no means inaccessible,
the screw may be rendered stationary at any time or during any weather,
when it would be barely safe to stop the engines with common paddles,
and when it would be very difficult to do anything to the paddles even
if the engines were stopped, while the whole of the screw, bearings,
&c., may easily be examined and felt from above, and, if necessary, men
sent down with common diving jackets and hoods to replace bearings, or
attach tackle to move the screw, or clear away any obstacle entangled in
it. When in port I still think the chances of injury very remote; an
inspection of our model will satisfy you that from the form and size of
her midship section the vessel cannot lay in any position in which the
screw would touch the ground, while at that time the whole screw may be
very easily examined and replaced without any necessity for going into
dock.
Thirdly, the probability of its being lifted out of water when the ship
pitches deep.
This appears at first to be a very natural and an unavoidable objection,
but the result of observations proves that the motion of vessels, of
steamers at least, is not such as to cause the apprehended difficulty.
Among the observations made on board the ‘Great Western’ steam-ship by
Mr. Berkeley Claxton, under my direction, were measurements of the
angles of rolling and pitching, and from these it was evident that the
vessel never pitches to so great an angle as that to which she rises;
such a result might indeed have been anticipated by considering the form
of the vessel forward and aft, and the circumstance that a steamer is
almost invariably meeting or passing the seas, or, if overtaken by them,
is still going at a good rate, which reduces the relative speed of the
sea; consequently, although the vessel may be frequently thrown up very
violently forward, yet the stern, which has no displacement under water,
settles down quietly and heavily upon the surface; or, considering it in
another way, the variation of displacement at the stern is very rapid,
falling off almost to nothing at a few feet below the water-line, and
spreading out to a great extent at a few feet above, whilst forward the
difference of displacement is comparatively small, the centre of motion,
therefore, is thrown very far aft, and while the bows, which are also
opposed to the first shock, are thrown alternately high out of water or
plunged deeply into it, the stern floats nearly steady, the vessel
resting on its broad counter nearly as the centre of motion: whatever
may be the explanation such is the operation, not only as measured by
instruments, but more particularly as observed since, practically.
In the ‘Great Western’ the whole cutwater and, it is said, a
considerable length of keel, is frequently seen out of water from the
bowsprit, while astern it is very doubtful whether more than half the
stern part was ever seen; marks have been made by my direction on the
rudder to observe this; as yet the 9-foot mark is the lowest seen, and
this occurring rarely, and for very short intervals.
In the ‘Archimedes,’ during a voyage performed in her by Mr. Guppy from
Bristol to Liverpool, and during which they were exposed on more than
one occasion to violent pitching, the screw (which can be watched from
the deck) never was uncovered; and Mr. Smith and others on board the
‘Archimedes,’ whose whole conduct was such as to inspire unusual
confidence in all information obtained from them, assured me that such
was always the case.
In the voyage to Oporto and back, in which I sent Mr. Berkeley Claxton,
he made the same observation; these facts, in conjunction with previous
and subsequent observations on board the ‘Great Western,’ convince me
that nothing is to be feared on this head; but even if the screw were
occasionally to be partly exposed, I know of no evil consequences likely
to ensue, as I shall clearly point out when referring to the
_advantages_ of this propeller over the common paddle.
Fourthly, the difficulty of getting up the required number of
revolutions, and the great defects of the mode employed in the
‘Archimedes.’
Upon this point certainly the ‘Archimedes’ offers but a miserable
example, and the result is almost enough to prejudice the mind of any
person against the whole scheme; the proportions of the gearing, as I
have before stated, are so bad that the engines appear, even to the eye,
to labour ineffectually to get up their speed. The required speed of the
screw is not nearly attained, while the noise and tremor caused by the
machinery is such as to render the vessel uninhabitable, and perfectly
unfit for passengers, I should almost say for a crew. I never attached
much importance to these circumstances, because I felt convinced that
such a mere mechanical difficulty would by some means be overcome, if,
as I confess I did not then at all anticipate, the screw itself should
prove efficient.
The most simple and effectual means of overcoming all objections on
these heads always appeared to me to be by the use of straps instead of
gearing; and all my experience, and I have seen a great deal of the
working of machinery by straps and ropes in the numerous works executed
by my father, led me to the conclusion that there existed no difficulty
whatever in sending the necessary power through a rope or hemp strap,
but I was hardly prepared to find the result so entirely satisfactory as
it has proved to be.
In an experiment made in your works at the yard, I have sent through
two small whale lines, a power equal to about one-thirtieth of that
which would be required in the strap if used in the new ship, and this
without any slip or straining of the rope which would be injurious in
practice, and without any peculiar means of ensuring adhesion to the
drums; so that we have ascertained beyond doubt that sixty such whale
lines upon a drum of only 4 feet 3 inches diameter is adequate to our
wants, but if we suppose seventy lines of superior manufacture to that
used in the experiments with a perfect mode of tightening and working
upon a drum of 6 feet diameter, all of which can easily be had, it will
ensure the perfect and easy working of a mode of obtaining the required
number of revolutions of the screw without noise or tremor. The strap in
question would be only about 3 feet or 3 feet 3 inches broad, easily
replaced piecemeal, and even, if necessary, without stopping the
engines.
All the difficulties enumerated under the fifth head may be considered
as entirely overcome, or rather as ceasing to exist; and so far from the
working of the screw involving difficulties and unavoidable friction,
noise, or tremor, it may be worked with unquestionable and perfect
facility, and as compared even with the best-made paddles in smooth
water, the whole machine will be noiseless.
It is almost unnecessary that I should say that the screw, apart from
the gearing in use on board the ‘Archimedes,’ _cannot_ and _does not_
produce the slightest tremor or noise--it was with some difficulty, and
at least only by attentively listening, that the revolutions of the
screw could be counted, even when disconnected and free from the noise
of the engine or gearing and the vessel being towed, and then only from
some defect in the bearings or the shaft of the screw causing a slight
beat.
In thus answering the objections supposed to have been urged against the
use of the screw, I may probably have appeared to see everything in a
favourable light; unhesitatingly I admit that it is so, and that both
formerly when I was completely sceptical as to the mere efficiency of
the screw as a propeller, and since my doubts on that head have been
removed, I always felt that upon all other points the screw possessed
every superiority that could be desired over a common paddlewheel for a
sea-going vessel.
I shall now proceed to point out the principal advantages peculiar to
the use of the screw; they are--
First. A considerable saving of weight, and that principally top weight.
Secondly. The admitting of a better and simpler form of vessel, having
greater stiffness with the same quantity of material, and offering less
resistance to head wind and seas, and affording more available space
within.
Thirdly. The operation of the screw being unaffected by the trim or the
rolling of the vessel, and allowing of the free use of sails, with the
capability of entirely disconnecting the screw or of varying the
multiplying motion so as to adapt the power of the engine to the
circumstance either of strong adverse winds or scudding.
Fourthly. Perfect regularity of motion and freedom from the possibility
of violent shocks to the engines.
Fifthly. The singularly increased power of steering given to the
vessel--and
Sixthly. The great reduction in the breadth of beam.
I have gone into some detail in calculating the weights of the parts
which are not common to the two systems, and I find that the difference,
or actual diminution in weight in favour of the screw as applied to our
new ship, is upwards of ninety-five tons; but that a much greater weight
even than this is transposed from the top of the ship to the bottom--no
less a mass than one hundred and sixty tons is removed from the level of
the paddle-shaft or from about 10 feet above the water-line, and
replaced by sixty-five tons at about 7 feet below the water-line; not
only is buoyancy, and consequently proportionate space for cargo, gained
to the extent of the difference, but the relief to the labouring of the
vessel in bad weather from the change of position must be immense. If
the reverse were under consideration, if in a vessel fitted for sea,
however stiff in trim or form, it were suggested to remove sixty-five
tons of her ballast, and to place one hundred and sixty tons upon her
deck, and thus navigate her across the Atlantic in all weathers, it
would probably be considered, not merely as highly dangerous, but as
actually impossible. Although such an opinion as that it would be
impracticable we now know would be incorrect, yet the extent of the
beneficial change is much more striking when considered in this way. As
regards the trim of the ship, about one hundred and forty-five tons
would be removed from nearly the centre of flotation, and the balance of
fifty tons added and distributed over the after part, principally quite
aft.
I have not calculated the exact effect of this upon her trim; it would
only bring her down by the stern, and this is a defect which there
seems, as we too well know, never any difficulty in remedying.
Secondly. The simplifying and improving the form of the ship--both as
regards strength and mass exposed to the wind and sea.
The necessity of contracting the midships of a steamer, and making her
completely wall-sided, and forming a sort of recess to receive the
paddles, interferes considerably with the framing of the ship. In a
wooden ship of the size of our new one the whole beam of the ship would
have to be contracted in order to carry the planking through in a direct
line and obtain the requisite fore and aft tie as has been done in the
‘Great Western’; in the new ship the almost infinite resources afforded
by the material used, enabled us to expand the sides and obtain breadth
of beam for cabin room, both before and abaft the paddles, and contract
the sides at the paddles as seen upon the plan; but in order to
strengthen this part, so evidently weak by form, much contrivance and
much material was required. By dispensing with paddles, the best form of
ship is left free to be adopted; perfect lines may be preserved, more
equal strength obtained with increased space, and the whole mass of
paddle-boxes and their accompanying sponsons and deck-houses swept away,
and the resistance of these huge wings to head winds or seas entirely
avoided.
The space gained by avoiding the contraction is calculated by Mr.
Patterson to amount to two hundred tons measurement; this would be
entirely gained, and would not even involve increased dues or tolls, as
it would be added to the engine-room; it would therefore perhaps
counterbalance any loss of room caused by the shaft conveying the
movement from the engine to the screw, but I believe this nominal
increase at one part would not be so great, while in fact the ship would
really be more compact, and, though to a very small extent, a smaller
ship, as the sponsons would be removed.
The third point of advantage named is perhaps the most important. With
paddles, the action is materially affected by the depth of immersion;
when the vessel is deep, and consequently the paddles deep, their action
is impeded, a greater part of the power of the engine is absorbed in
driving the paddle, the speed of the engine is reduced and the effect
diminished; when too light also the paddles do not take sufficient hold
of the water, the amount of slip increases and power is wasted; in
rolling the same effects are produced, and thus at those times when the
greatest effect is required, namely, with deep immersion or in bad
weather to overcome the increased resistance offered to the vessel, the
propelling power is least effective, and Captain Hoskins actually
estimates this loss as occasionally equal to two-thirds the whole power.
The bad effects of one paddle being immersed too deeply, and the other
not sufficiently, also prevents the free use of the sails; and it must
often occur that the impediment thus offered to the working of the
paddles more than counterbalances the good effects of a tolerably fair
wind. With the screw the effect is constant, at least unaffected by the
position or motion of the ship, whether deep or light the screw acts
nearly the same, and as to rolling or heeling over, the screw would work
equally well (as long as it be immersed) if the vessel were on her
beam-ends or bottom upwards.
The screw therefore leaves the ship free to be used as a sailing-vessel
to any extent that other circumstances will admit of, and as long as the
sails draw there can generally be no doubt that the wind is assisting
the ship. The screw may also be thrown in and out of gear at any time
and during any weather, either in case of accident to the engines, or in
the event of her scudding before a gale of wind, when the engine would
be useless; this last, however, I do not consider a probable occurrence,
particularly if another arrangement of which the screw is susceptible be
taken advantage of.
If the motion be conveyed by a strap, as I have recommended, there is no
difficulty in having two or even three drums on the screw-shaft of
different diameters, and thus when the resistance to the ship is very
much increased by strong head winds, deep draught, and other causes, to
use the slow motion and obtain an increased propelling force, or when,
on the contrary, the vessel is running before the wind to use the quick
motion--by which, in both cases, a great increase of speed would be
attained.
This is in fact obtaining at once and by simple means all those
advantages, and to a much fuller extent, which are aimed at in the
reefing-paddles.
Fourthly, great regularity of motion is naturally consequent upon the
screw being unaffected by the rolling of the ship, and upon its being
immersed and not exposed therefore to blows from the sea, and except in
the case of its being lifted out of water, the resistance is perfectly
uniform and perfectly smooth.
An engine could not have a work less capable of causing any jar or shock
as to the effect; even if lifted partially out of water the variation of
resistance would be as easy or soft, to use a mechanical term, as
possible, while the extent of the variation could never approach to that
to which paddles continually expose an engine. A heavy sea or a deep
plunge will occasionally bring the engines nearly to a stand; while at
other moments, if the engineers are to be believed, the paddles are left
free and the engines run away at a fearful speed. I am inclined to think
this description of the effects somewhat exaggerated; but certainly the
screw cannot by possibility be exposed to the same variations as the
paddles--it cannot be stopped by the action of the sea, indeed, being
wholly immersed, the resistance cannot be increased at all, while under
no circumstances can it be relieved to the extent to which paddles are,
which may both on some rare occasions be quite out of the water; and
therefore whether the resistance of the screw is so constant as I
believe it to be, or not, yet as compared with that offered by paddles,
it is certainly all but perfectly constant.
Fifthly, the effect upon the steerage is singular, the mass of water put
into motion by the thrust of the screw is thrown directly upon the
rudder, and the consequence is not only that when the ship is going at
any given rate, the rudder is passing through the water at a greater
rate, and consequently is more sensible, and acts more powerfully upon
the ship; but even when the ship has no way, but the screw is at work,
the rudder is acted upon by water moving perhaps at two or three knots
per hour, and the vessel is still under command--this must be a most
important power to possess in a ship, and must materially diminish many
of the greatest dangers arising from a strong head wind and sea, and at
the same time and under the same circumstances must increase the speed
by improving the steerage.
And lastly, her diminished breadth of beam. Important as this alteration
would be to any vessel, it is peculiarly so as connected with Bristol;
the total breadth, including paddle-boxes, would be at least 78 feet;
with the screw, and taking all the increased beam that might be
convenient, it would be under 50--very nearly 30 feet of difference. One
of the principal objections to her coming up the river would be removed,
and the dock gates might easily be made to receive her.[201]
There are many other points upon which comparisons may be drawn, but I
am not aware that any very important differences exist.
As regards first cost I believe there would be little difference--if
any, it would be in favour of the screw; as a reduction of ninety-five
tons of iron can hardly fail to cause some saving, although some portion
of the substituted machinery may be more costly per ton.
As regards wear and tear I can have no doubt that some considerable
saving would be effected; the paddles are a constant source of trouble
and expense, and seem never to be capable of being kept in good repair;
indeed, they are huge and comparatively light frameworks subjected to
extraordinary and constantly repeated shocks, each arm receiving direct
about 260,000 very sharp blows per voyage, independently of the more
violent shocks from heavy seas, while the screw can be subjected to no
such constant source of mischief.
From all that I have said it must be evident to you, gentlemen, that my
opinion is strong and decided in favour of the advantage of employing
the screw in the new ship; it certainly is so. I am fully aware of the
responsibility I take upon myself by giving this advice, I am also fully
sensible of the large amount we have at stake, and I have not forgotten
the nature and tone of the observations which have on more occasions
than one been so freely made by individuals upon the course we have
hitherto pursued; although, and I have pleasure in referring to the
fact, this course has in every instance where results have been obtained
proved successful; but my conviction of the wisdom, I may almost say the
necessity, of our adopting the improvement I now recommend is too
strong, and I feel it is too well founded, for me to hesitate or to
shrink from the responsibility.
I think I have hardly advanced an opinion which I have not supported,
and in most cases preceded, by a statement of facts, leaving no doubt as
to the correctness and safety of relying on these opinions; still it
would be too much to hope that my mode of laying before you these facts
which I have collected and the opinions I have formed could produce as
strong a conviction in your minds as the consideration of them has in my
own; but if you bear in mind that the actual results of the fair and
full trial of the ‘Archimedes’ for several months has completely
established the fact of the efficiency of the screw as a propeller; that
the experiments I have made, as well as the general and apparent results
of her working, have equally satisfactorily explained the fact of the
power required being no greater in proportion to the effect produced
than in the ‘Great Western’ steam-ship, and many other good steamboats;
and that these results are satisfactorily explained by theory, you
cannot fail to draw the same conclusion that I have done as to the
general question of at least the equal efficiency of the screw.
As to the comparisons I have drawn between the general and what I may
call the indirect advantages of the one mode of propelling over the
other, they seem to me so evident that I am disposed to apologise to you
for having occupied your time in pointing them out, and we have the
satisfaction of knowing that they are now very generally admitted,
particularly by practical men.
In conclusion, I must observe that much more detailed information and
recorded results than appear on the face of this Report have been
required to enable me to form correct comparisons, and to reduce to
calculation and to actual figures and amounts many results observed; and
that it would have been impossible for me to have given you such clear
and positive facts on many most important points without the very
detailed observations made and recorded by Mr. Berkeley Claxton in the
several voyages of the ‘Great Western,’ and also in one on board the
‘Archimedes.’
The information obtained from these logs has been, and may still be, of
the greatest importance to us in our future working, and I have much
pleasure in adding that the manner in which my directions were carried
out was highly creditable to Mr. Berkeley Claxton, who, I think, has
conferred a great benefit on the Company by his labours. I have to
express also my thanks to my friends Captain Claxton and Mr. Guppy for
their assistance in the various experiments which have been made, and in
working out the results.
I am, Gentlemen,
Yours very faithfully,
(Signed) I. K. BRUNEL.
INDEX