Autobiography of Sir John Rennie, F.R.S 58
recommended that an intercepting sewer should be made round the basin,
so that all the sewage should be diverted from the town and harbour into
the sea, to the westward, and by this means it was carried away by the
tide, and a great nuisance taken away from the town. There was no regular
tide gauge to ascertain the exact rise and fall of the tide, so that the
harbour light at night could not be shown at the proper time, neither
could the day signal be hoisted to show when there was sufficient depth
at the entrance. This defect I remedied by establishing a self-acting
tide gauge in a well within the lighthouse at the west pier-head. The
pole of this tide gauge was connected with a cylinder and a clock hand;
on the cylinder was a roll of paper, and to the hand of the clock was
attached a pencil, which, as the rod or tide gauge rose and fell, marked
it on the paper; thus the rise and fall of every tide was indicated upon
the paper, and the clock showed the time, so that the rise and fall of
every tide was regularly registered and kept in a book from year to
year. I also established barometers at different parts of the harbour,
under lock and key, the latter of which was kept by the harbour-master;
these barometers were set every morning, and the rise and fall was
registered in a book, so that all the captains of vessels in the harbour
could ascertain as nearly as practicable the state of the weather;
rain gauges were also established, a regular account of the rainfall
being registered. Before my time the trustees had got an admirable time
clock, by Moore, for which they paid 200_l._, and Mr. Turner, one of
the chairmen of the trustees, got another clock from Dent’s, which cost
105_l._ These two clocks were kept in repair by a competent person, and
corresponded to a second with the Royal Observatory time at Greenwich,
hence every captain of a vessel starting from Ramsgate could carry
the correct time with him. Thus Ramsgate was provided with all the
instruments for ascertaining the correct time, the state of the tides,
together with the barometer, thermometer, the wind and rain gauges, and
everything necessary to indicate the probable state of the weather.
All harbours ought to be provided with these instruments, and a regular
journal should be kept, forming a careful record of the observations made
from them. After the harbour was transferred to the Board of Trade I
still continued as principal engineer, at the same salary, viz. 315_l._
per annum and travelling expenses.
In the middle of the last century a breach was made on the left bank of
the Thames, near the village of Dagenham, and many thousand acres of the
adjacent lowlands were inundated. The most skilful engineers of the day
tried long and in vain to close the breach, but at last it was effected
by Captain Perie, at a cost of 20,000_l._; but although the breach was
closed, and nearly the whole submerged lands relieved from the water,
still a space amounting to about 100 acres, where the breach took place,
has ever since remained covered, and is called Dagenham Lake at the
present day.
The position of this fine sheet of water being on the London side of the
Thames, its depth varying from 4 to 20 feet below low water of spring
tides, the great depth and width of the river in front of it and its
proximity to London render it admirably adapted for wet or floating
docks. For a long time it passed unnoticed, until, the trade of London
increasing, other docks were established on both sides of the Thames at
and close to London; the enormous cost of these and the high rates which
they were necessarily obliged to charge in order to get anything like
a remunerating dividend for the capital expended, induced enterprising
people to look out for some situation lower down the river where docks
could be established upon more moderate terms, and where consequently
the rates would be much lower. Amongst other places Dagenham Lake
attracted their notice, and very naturally so, for it possessed all
the requisites for making a complete establishment of the kind at a
most moderate cost, far below that which had been expended upon any of
the great dock establishments in London. Who were the first persons
who originated the idea of converting Dagenham Lake into a great dock
establishment I do not know, but amongst others, I am told, was Mr.
George Burge, the well-known contractor, about 1845. Subsequently Mr.
Crampton took up the idea, and proposed to convert Dagenham Lake into a
great dock establishment nearly twenty years ago, but the project never
came to maturity. At last Mr. George Remington, a well-known projector,
entered into it in 1854, and asked me to join him. On investigating
the subject I was satisfied of its intrinsic merits, and agreed to
co-operate in the undertaking. A Bill was therefore obtained in the year
1855 for this purpose. It was simply proposed in the first instance to
connect the Dagenham Lake with the Thames by means of a lock, together
with some small warehouses, landing wharves, and a railway to connect
it with the London and Tilbury line; the whole estimate of what it was
proposed to do there being confined to 120,000_l._, that is to say,
90,000_l._ subscriptions, and borrowing power of 30,000_l._ This, it
must be observed, was merely to commence the undertaking upon a moderate
scale; and it was intended to extend the quays and warehouse room in
proportion as the increased trade required it, for the floating basin
accommodation was equal to that of the largest docks in London, and the
depth of water in the river and in the dock was greater. The dock, if it
could be commenced upon this moderate scale, could not, it is true, have
been considered as a powerful rival to the other dock establishments, but
it would have relieved them from the greatest part of the lumber trade,
which they could not accommodate without great inconvenience and even
loss, such as the timber, guano, hemp, flax, coal trades, &c.; moreover,
it would give accommodation for laying up in ordinary the great number of
vessels which are always more or less unemployed in the port of London.
It is computed that of unemployed vessels there are generally about
150,000 tons; now these vessels, at a penny per ton per week, would
alone return 7000_l._ per annum, and as they require no superintendence
except from their owners, they alone would have paid 5 per cent. upon the
total capital of the Company, and all the other trade would have added
so much more to their income. It was quite clear that it would be to the
interest of all the unemployed vessels to lay up there, because they
could do so at half the expense compared with the other docks; for even
if they were to lie at their moorings in the river, although they would
be charged nothing, still their expenses would be a great deal more.
There was, besides, another trade open to these docks, that could not
be accommodated in any of the others, namely, the foreign cattle trade,
which is every day increasing, and which must continue to increase with
the population of the metropolis.
The first Act, as I have already said, passed in 1855, and although
several attempts were made to form a company to carry it into effect,
they all failed. In 1862 another Act of Parliament was obtained, as the
original one had nearly expired. In the new Act the powers were enlarged,
and the works were extended to 300,000_l._, with power to borrow
100,000_l._ more; and it was again attempted to form a company to carry
it into effect, but failed. In 1865 a third attempt was made to form a
company, and by the aid of Messrs. Rigby, the well-known contractors of
the great Admiralty harbour at Holyhead, a company was at length formed.
Those gentlemen contracted for the works at a certain price, and agreed
to take a large number of the shares as well in payment. The works
commenced under my direction, in the month of May 1865, and proceeded
very well until the end of March 1866, when the Messrs. Rigby got into
difficulties, and were unable to complete their contract, and the
consequence was that the whole of the works were stopped. The state of
the money market ever since has been so depressed that it has hitherto
been impossible to find the money to carry them on, and thus this really
valuable concern remains still in abeyance.
In 1866 another Act of Parliament was procured, enabling the Company to
obtain more land and to increase the works, so that ultimately, when
times become favourable, it is very probable that this great undertaking
will be carried out, and will form one of the largest and most important
dock establishments on the banks of the Thames.
During the year 1866 it was attempted to obtain an Act of Parliament for
making a railway between Romford and the docks. It passed the House of
Commons, but when it got into the House of Lords its supporters drew back
and the Bill was abandoned.
CHAPTER X.
Retrospect--London Bridge--Sheerness Dockyard--Plymouth
Breakwater and Victualling Yard--Steam Vessels for the
Navy--Harbours--Railways--Broad and Narrow Gauge--Atmospheric
Railway--Water Supply and Sewage.
I have thus endeavoured to give, in the foregoing narrative, an account
of my professional and private life as near as my memory would serve.
I have not had a single date, or note-book, or journal to refer to; so
that many inaccuracies may have occurred, particularly with regard to the
dates, although the facts and circumstances are, I believe, pretty fairly
narrated.
In my professional career I consider that I have executed the following
works:
I. London Bridge. This was designed by my father, as far as the general
outline and proportions, but he did not live long enough to design any
details, such as the depth of the arch-stones and those of the inverted
arches between the main arches, or the adjustment of them, so that the
whole might be placed in a perfect state of equilibrium, not only as
regards the individual arches, but also with each other; neither was the
width of the foundations of the piers and abutments given, nor the extent
of piling necessary, the cornice and parapets, stairs, pilasters of the
piers and abutments, the construction of the cofferdams and centres; the
specification as to what materials should be used, and how they were to
be put together; the approaches to the bridge on both sides, or how they
were to be designed and put together; all these had to be worked out
and executed by myself. It is true that my brother George gave me his
advice when I required it, but still I was the sole engineer, and the
whole responsibility rested with myself. The execution of these works was
rendered much more difficult than intended by my father, for at his death
the site was that of the old bridge. But the Committee of the Corporation
of London insisted that the new bridge should be built immediately above
the old one, the latter to be left standing during the construction of
the new bridge. I was therefore obliged to build it in the deep hole
above the old bridge, which was from 25 to 30 feet below the level of
low-water mark of spring tides.
II. The completion of the great works of Sheerness Dockyard. These, as
I have said, had been wholly designed by my father upon an entirely
original and novel plan of hollow walls, which he first carried into
effect at Great Grimsby Docks, in the year 1786. These walls, though
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