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found that only about ten acres remained for the docks； but these；
from the nature of the ground； presented an unusual amount of quay
room。 The necessary Act was obtained in 1825； the works were begun
in the following year； and on the 25th of October； 1828； the new
docks were completed and opened for business。
The St。 Katherine Docks communicate with the river by means of an
entrance tide…lock； 180 feet long and 45 feet wide； with three
pairs of gates； admitting either one very large or two small
vessels at a time。 The lock…entrance and the sills under the two
middle lock…gates were fixed at the depth of ten feet under the
level of low water of ordinary spring tides。 The formation of these
dock…entrances was a work of much difficulty； demanding great skill
on the part of the engineer。 It was necessary to excavate the
ground to a great depth below low water for the purpose of getting
in the foundations； and the cofferdams were therefore of great
strength； to enable them； when pumped out by the steam…engine； to
resist the lateral pressure of forty feet of water at high tide。
The difficulty was； however； effectually overcome； and the wharf
walls； locks； sills and bridges of the St。 Katherine Docks are
generally regarded as a master…piece of harbour construction。
Alluding to the rapidity with which the works were completed；
Mr。 Telford says： 〃Seldom； indeed never within my knowledge； has there
been an instance of an undertaking； of this magnitude； in a very
confined situation； having been perfected in so short a time；。。。。
but； as a practical engineer； responsible for the success of
difficult operations； I must be allowed to protest against such
haste； pregnant as it was； and ever will be； with risks； which； in
more instances than one； severely taxed all my experience and
skill； and dangerously involved the reputation of the directors as
well as of their engineer。〃
Among the remaining bridges executed by Mr。 Telford； towards the
close of his professional career； may be mentioned those of
Tewkesbury and Gloucester。 The former town is situated on the
Severn at its confluence with the river Avon； about eleven miles
above Gloucester。 The surrounding district was rich and populous；
but being intersected by a large river； without a bridge； the
inhabitants applied to Parliament for powers to provide so
necessary a convenience。 The design first proposed by a local
architect was a bridge of three arches； but Mr。 Telford； when
called upon to advise the trustees； recommended that； in order to
interrupt the navigation as little as possible； the river should be
spanned by a single arch； and he submitted a design of such a
character； which was approved and subsequently erected。 It was
finished and opened in April； 1826。
This is one of the largest as well as most graceful of Mr。 Telford's
numerous cast iron bridges。 It has a single span of 170 feet； with
a rise of only 17 feet； consisting of six ribs of about three feet
three inches deep； the spandrels being filled in with light
diagonal work。 The narrow Gothic arches in the masonry of the
abutments give the bridge a very light and graceful appearance；
at the same time that they afford an enlarged passage for the high
river floods。
The bridge at Gloucester consists of one large stone arch of 150
feet span。 It replaced a structure of great antiquity； of eight
arches； which had stood for about 600 years。 The roadway over it
was very narrow； and the number of piers in the river and the small
dimensions of the arches offered considerable obstruction to the
navigation。 To give the largest amount of waterway； and at the same
time reduce the gradient of the road over the bridge to the
greatest extent； Mr。 Telford adopted the following expedient。
He made the general body of the arch an ellipse； 150 feet on the
chord…line and 35 feet rise； while the voussoirs； or external
archstones； being in the form of a segment； have the same chord；
with only 13 feet rise。 〃This complex form；〃 says Mr。 Telford；
〃converts each side of the vault of the arch into the shape of the
entrance of a pipe； to suit the contracted passage of a fluid； thus
lessening the flat surface opposed to the current of the river
whenever the tide or upland flood rises above the springing of the
middle of the ellipse； that being at four feet above low water；
whereas the flood of 1770 rose twenty feet above low water of an
ordinary spring…tide； which； when there is no upland flood； rises
only eight or nine feet。〃*＇1＇ The bridge was finished and opened in
1828。
＇Image＇ Dean Bridge； Edinburgh。
The last structures erected after our engineer's designs were at
Edinburgh and Glasgow： his Dean Bridge at the former place； and his
Jamaica Street Bridge at the latter； being regarded as among his
most successful works。 Since his employment as a journeyman mason
at the building of the houses in Princes Street； Edinburgh； the New
Town had spread in all directions。 At each visit to it on his way
to or from the Caledonian Canal or the northern harbours； he had
been no less surprised than delighted at the architectural
improvements which he found going forward。 A new quarter had risen
up during his lifetime； and had extended northward and westward in
long lines of magnificent buildings of freestone； until in 1829 its
further progress was checked by the deep ravine running along the
back of the New Town； in the bottom of which runs the little Water
of Leith。 It was determined to throw a stone bridge across this
stream； and Telford was called upon to supply the design。 The point
of crossing the valley was immediately behind Moray Place； which
stands almost upon its verge； the sides being bold； rocky； and
finely wooded。 The situation was well adapted for a picturesque
structure； such as Telford was well able to supply。 The depth of
the ravine to be spanned involved great height in the piers； the
roadway being 106 feet above the level of the stream。 The bridge
was of four arches of 90 feet span each； and its total length 447
feet； the breadth between the parapets for the purposes of the
roadway and footpaths being 39 feet。*＇2＇ It was completed and
opened in December； 1831。
But the most important； as it was the last； of Mr。 Telford's stone
bridges was that erected across the Clyde at the Broomielaw；
Glasgow。 Little more than fifty years since； the banks of the river
at that place were literally covered with broomand hence its
namewhile the stream was scarcely deep enough to float a
herring…buss。 Now； the Broomielaw is a quay frequented by ships of
the largest burden； and bustling with trade and commerce。 Skill and
enterprise have deepened the Clyde； dredged away its shoals； built
quays and wharves along its banks； and rendered it one of the
busiest streams in the world；
It has become a great river thoroughfare； worked by steam。 On its
waters the first steamboat ever constructed for purposes of traffic
in Europe was launched by Henry Bell in 1812； and the Clyde boats
to this day enjoy the highest prestige。
The deepening of the river at the Broomielaw had led to a gradual
undermining of the foundations of the old bridge； which was
situated close to the principal landing…place。 A little above it；
was an ancient overfall weir； which had also contributed to scour
away the foundations of the piers。 Besides； the bridge was felt to
be narrow； inconvenient； and ill…adapted for accommodating the
immense traffic passing across the Clyde at that point。 It was；
therefore； determined to take down the old structure； and Build a
new one； and Mr。 Telford was called upon to supply the design。
The foundation was laid with great ceremony on the 18th of March； 1833；
and the new bridge was completed and opened on the 1st of January；
1836； rather more than a year after the engineer's death。 It is a
very fine work； consisting of seven arches； segments of circles；
the central arch being 58 feet 6 inches； the span of the adjoining
arches diminishing to 57 feet 9 inches； 55 feet 6 inches； and 52
feet respectively。 It is 560 feet in length； with an open waterway
of 389 feet； and its total width of carriageway and footpath is 60
feet； or wider； at the time it was built； than any river bridge in
the kingdom。
＇Image＇ Glasgow Bridge
Like most previous engineers of eminencelike Perry； Brindley；
Smeaton； and RennieMr。 Telford was in the course of his life
extensively employed in the drainage of the Fen districts。 He had
been jointly concerned with Mr。 Rennie in carrying out the
important works of the Eau Brink Cut； and at Mr。 Rennie's death he
succeeded to much of his practice as consulting engineer。
It was principally in designing and carrying out the drainage of
the North Level that Mr。 Telford distinguished himself in Fen
drainage。 The North Level includes all that part of the Great
Bedford Level situated