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not taken the business out of the hands of the General Committee；
and got it referred to a Select Committee。 Last year they
recommended that a system of docks should be formed in a large bend
of the river opposite Greenwich； called the Isle of Dogs； with a
canal across the neck of the bend。 This part of the contemplated
improvements is already commenced； and is proceeding as rapidly as
the nature of the work will admit。 It will contain ship docks for
large vessels； such as East and West Indiamen； whose draught of
water is considerable。
〃There are now two other propositions under consideration。 One is
to form another system of docks at Wapping； and the other to take
down London Bridge； rebuild it of such dimensions as to admit of
ships of 200 tons passing under it； and form a new pool for ships
of such burden between London and Blackfriars Bridges； with a set
of regular wharves on each side of the river。 This is with the view
of saving lighterage and plunderage； and bringing the great mass of
commerce so much nearer to the heart of the City。 This last part of
the plan has been taken up in a great measure from some statements
I made while in London last year； and I have been called before the
Committee to explain。 I had previously prepared a set of plans and
estimates for the purpose of showing how the idea might be carried
out； and thus a considerable degree of interest has been excited on
the subject。 It is as yet； however； very uncertain how far the
plans will be carried out。 It is certainly a matter of great
national importance to render the Port of London as perfect as
possible。〃*＇7＇
Later in the same year he writes that his plans and propositions
have been approved and recommended to be carried out； and he
expects to have the execution of them。 〃If they will provide the
ways and means；〃 says he； 〃and give me elbow…room； I see my way as
plainly as mending the brig at the auld burn。〃 In November； 1801；
he states that his view of London Bridge； as proposed by him； has
been published； and much admired。 On the l4th of April； 1802； he
writes； 〃I have got into mighty favour with the Royal folks。 I have
received notes written by order of the King； the Prince of Wales；
Duke of York； and Duke of Kent； about the bridge print； and in
future it is to be dedicated to the King。〃
The bridge in question was one of the boldest of Telford's designs。
He proposed by his one arch to provide a clear headway of 65 feet
above high water。 The arch was to consist of seven cast iron ribs；
in segments as large as possible； and they were to be connected by
diagonal cross…bracing； disposed in such a manner that any part of
the ribs and braces could be taken out and replaced without injury
to the stability of the bridge or interruption to the traffic over it。
The roadway was to be 90 feet wide at the abutments and 45 feet
in the centre； the width of the arch being gradually contracted
towards the crown in order to lighten the weight of the structure。
The bridge was to contain 6500 tons of iron； and the cost of the
whole was to be 262；289L。
＇Image＇ Telford's proposed One…arched Bridge over the Thames。
The originality of the design was greatly admired； though there
were many who received with incredulity the proposal to bridge the
Thames by a single arch； and it was sarcastically said of Telford
that he might as well think of 〃setting the Thames on fire。〃
Before any outlay was incurred in building the bridge； the design
was submitted to the consideration of the most eminent scientific
and practical men of the day； after which evidence was taken at
great length before a Select Committee which sat on the subject。
Among those examined on the occasion were the venerable James Watt
of Birmingham； Mr。 John Rennie； Professor Button of Woolwich；
Professors Playfair and Robison of Edinburgh； Mr。 Jessop；
Mr。Southern； and Dr。 Maskelyne。 Their evidence will still be found
interesting as indicating the state at which constructive science
had at that time arrived in England。*＇8＇ There was a considerable
diversity of opinion among the witnesses； as might have been
expected； for experience was as yet very limited as to the
resistance of cast iron to extension and compression。 Some of them
anticipated immense difficulty in casting pieces of metal of the
necessary size and exactness； so as to secure that the radiated
joints should be all straight and bearing。 Others laid down certain
ingenious theories of the arch； which did not quite square with the
plan proposed by the engineer。 But； as was candidly observed by
Professor Playfair in concluding his report〃It is not from
theoretical men that the most valuable information in such a case
as the present is to be expected。 When a mechanical arrangement
becomes in a certain degree complicated； it baffles the efforts of
the geometer； and refuses to submit to even the most approved
methods of investigation。 This holds good particularly of bridges；
where the principles of mechanics； aided by all the resources of
the higher geometry； have not yet gone further than to determine
the equilibrium of a set of smooth wedges acting on one another by
pressure only； and in such circumstances as； except in a
philosophical experiment； can hardly ever be realised。 It is；
therefore； from men educated in the school of daily practice and
experience； and who to a knowledge of general principles have
added； from the habits of their profession； a certain feeling of
the justness or insufficiency of any mechanical contrivance； that
the soundest opinions on a matter of this kind can be obtained。〃
It would appear that the Committee came to the general conclusion
that the construction of the proposed bridge was practicable and
safe； for the river was contracted to the requisite width； and the
preliminary works were actually begun。 Mr。 Stephenson says the
design was eventually abandoned； owing more immediately to the
difficulty of constructing the approaches with such a head way；
which would have involved the formation of extensive inclined
planes from the adjoining streets； and thereby led to serious
inconvenience； and the depreciation of much valuable property on
both sides of the river。*＇9＇ Telford's noble design of his great
iron bridge over the Thames； together with his proposed embankment
of the river； being thus definitely abandoned； he fell back upon
his ordinary business as an architect and engineer； in the course
of which he designed and erected several stone bridges of
considerable magnitude and importance。
In the spring of 1795； after a long continued fall of snow； a
sudden thaw raised a heavy flood in the Severn； which carried away
many bridgesamongst others one at Bewdley； in Worcestershire；
when Telford was called upon to supply a design for a new structure。
At the same time； he was required to furnish a plan for a new
bridge near the town of Bridgenorth； 〃in short；〃 he wrote to his
friend； 〃I have been at it night and day。〃 So uniform a success had
heretofore attended the execution of his designs； that his
reputation as a bridge…builder was universally acknowledged。
〃Last week；〃 he says； 〃Davidson and I struck the centre of an arch
of 76 feet span； and this is the third which has been thrown this
summer； none of which have shrunk a quarter of an inch。〃
Bewdley Bridge is a handsome and substantial piece of masonry。
The streets on either side of it being on low ground； land arches
were provided at both ends for the passage of the flood waters；
and as the Severn was navigable at the point crossed； it was
considered necessary to allow considerably greater width in the
river arches than had been the case in the former structure。
The arches were three in numberone of 60 feet span and two of 52
feet； the land arches being of 9 feet span。 The works were
proceeded with and the bridge was completed during the summer of
1798； Telford