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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 considerableobstruction 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 extendednorthward and westward in
long lines of magnificent buildings of freestone, until in 1829 its

further progress was checked by the deep ravinerunning 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 broom--and hence its

name--while 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 eminence--like Perry, Brindley,
Smeaton, and Rennie--Mr. 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 between Morton's Leam and the river Welland,

comprising about 48,000 acres of land. The river Nene, which brings
down from the interior the rainfall of almost the entire county of

Northampton, flows through nearly the centre of the district.
In some places the stream is confined by embankments, in others it

flows along artificial outs, until it enters the great estuary of
the Wash, about five miles below Wisbeach. This town is situated on

another river which flows through the Level, called the Old Nene.
Below the point of junction of these rivers with the Wash, and

still more to seaward, was South Holland Sluice, through which the
waters of the South Holland Drain entered the estuary. At that

point a great mass of silt had accumulated, which tended to choke
up the mouths of the rivers further inland, rendering their

navigation difficult and precarious, and seriously interrupting the
drainage of the whole lowland district traversed by both the Old

and New Nene. Indeed the sands were accumulating at such a rate,
that the outfall of the Wisbeach River threatened to become

completely destroyed.
Such being the state of things, it was determined to take the

opinion of some eminent engineer, and Mr. Rennie was employed to
survey the district and recommend a measure for the remedy of these

great evils. He performed this service in his usually careful and
masterly manner; but as the method which he proposed, complete

though it was, would have seriously interfered with the trade of
Wisbeach, by leaving it out of the line of navigation and drainage

which he proposed to open up, the corporation of that town
determined to employ another engineer; and Mr Telford was selected

to examine and report upon the whole subject, keeping in view the
improvement of the river immediately adjacent to the town of

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