Looking at a map of the city for the year 1778 we see iust two bridges, one at foot of Stock well Street, leading to the “Gorbells”—a small district of about one or two streets, and at that time the only part built on the south side; another, called the “New Bridge,” crossed the river at the foot of Jamaica Street, the most important building near it on the south side being a windmill near the river, and standing in the Windmill Croft.

Looking at another map of the city for the year 1818 we see three bridges shown, joining the north and south sides of the river. One at the foot of Saltmarket, one at the foot of Stockwell Street, and one at the foot of Jamaica Street. On the south side we now see various streets and buildings divided into the districts of Hutcheson Town, Laurieston, and Trades Town. The windmill has disappeared, and amongst a few single-masted sailing boats we see a solitary steamer.

The bridge spanning the river from Saltmarket Street to Hutchesontown was at one time made of wood, and was built in 1803. This bridge was about 340 feet in length, having eight supporting piers; the width was only a little over 7 feet. It was raised up so much above the river— probably to allow flood water to pass underneath safely— that stairs were required at each end to get on to it from the roadway. Later on, a stone bridge was built about the same position. The inscription, coins, papers, &c., which were placed at the laying of the foundation of the stone bridge, are to be seen in the Kelvingrove Museum. In 1871 the present handsome Albert Bridge was erected. This bridge consists of three spans, one of 114 ft. and two of 108 ft. each; the width is 60 ft.; it is constructed of wrought iron. The piers are formed of cast-iron cylinders, sunk to a depth of from 65 ft. to 80 ft., through strata of sand, mud, and gravel, until the sandstone rock is reached.

A wooden bridge appears to have existed as early as the fourteenth century, as a stone bridge was erected by Bishop Rae in its place in 1345. This bridge spanned the river at the foot of Stockwell Street. The present bridge was built in 1851.

The old Jamaica Street Bridge was erected in 17G7, and gave place to the present handsome building, designed by Telford, and founded 1833. In reference to this work of the great engineer (who, besides road-making and ordinary stone-bridge building, successfully spanned the Menai Straits with his iron suspension bridge), Smiles, in his Lives of the Engineers, says: “ 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 foundation of the old bridge, which was situated close to the existing 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 lie 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 foot-path is 60 feet, or wider, at the time it was built, than any river-bridge in the kingdom.”

Some years ago, after the removal of the weir above referred to, it appeared that the increased scour due to this removal, or to the constant dredging operations going on below, was affecting the foundations of the piers of the bridge. These foundations had been made on piles sunk into the bed of the river, which at this part consists mainly of silt and sand. Steps were accordingly taken to strengthen the parts required. This was effected by placing aprons of concrete around the foot of the piers. The roadway referred to above as being noticeable for its width has long been felt to be insufficient for the immense traffic which daily crosses the bridge.

The railway bridge erected by the Caledonian Railway to carry that line into the Central Station, is situated immediately below the Glasgow Bridge just referred to. It consists of three spans of lattice-girders resting on iron piers sunk in the river bed until a sufficiently solid foundation was reached; in this case the depth of loose material, silt, sand, &c., which had to be penetrated was as much as 80 feet. The bridge carries four lines of rails. The contractor for the erection of this bridge, Mr. Wm. Arrol, like his great predecessor Telford, has made a name for himself as a bridge builder, the gigantic structures of the Forth and Tay Bridges having been intrusted to him to carry out. The successful completion of the Tay Bridge having just been accomplished, gives us the more assurance that in a short time we shall gee the projecting arms of the Forth Bridge stretching their 1700 feet of steel framework across the deep and fast-flowing waters of the Forth. Mr. Arrol has the inventive faculty and ready resource of the early engineers and builders who have laid the foundation of our engineering celebrity as a nation.

Another railway bridge, carrying the Glasgow and South-Western traffic, spans the river below the Albert Bridge. Like the Caledonian Railway Bridge further down, the girders are of the lattice type and carried on piers. A suspension bridge above the Jamaica Street Bridge, and another higher up connecting the Green with the south side, completes the existing number of Glasgow bridges. The cross traffic is, however, so great, that proposals are occasionally made and discussed as to additional facilities further down the river than Glasgow Bridge, whether by subways, high-level bridges, or other special means has as yet not been decided.

In the meantime the ferry traffic for passengers is admirably conducted at various points in the harbour and further down by means of steam ferry-boats having a screw propeller at each end, thus rendering turning unnecessary.

Bridges, like ships, are indispensable as links of communication, and from an early period have had much attention paid to their design and construction. With the introduction of the railway system a great development took place in bridge building, and as in many cases the spans required and sites to be occupied were of such a nature as to prohibit the use of stone or wood, iron was employed, and a new form of structure gradually appeared, differing much in design and construction from the old stone arch. The tubular-girder bridges across the Mcnai Straits, and the St. Lawrence at Montreal, are great examples of a special form of structure adopted by Robert Stephenson, who with his father George were the early pioneers of the railway system.

Brunei, noted for his daring genius, bridged the Tamar at Saltash with two bows of |f-33 ft. span made hollow in section, and connected at the ends by chains, which, acting as ties, resist the thrust through the bow due to the load, somewhat as in the later “bowstring” form.

Zigzag, or “Warren” girders, lattice-girders, and arch-rib structures all followed in rapid succession. Suspension bridges with supporting medium of chains or wire-ropes were flung across wide and deep ravines where scaffolding could not find a place. And now at the present time, thanks to the skill of the steel manufacturer, the engineer has placed at his disposal a material which enables him to take still wider leaps than his predecessors, and project bridges across wide and dangerous rivers and estuaries which a few years ago would have been deemed almost impossible. Steel as now manufactured readily lends itself to these requirements, as from its now well-established reliability, great tenacity, and ductility, it is well adapted to railway bridges, as the strength can be easily varied in the manufacture to suit any special demands by the engineer.

The great structure now erecting across the Forth at Queensferry is designed on the cantilever system; it is composed of steel and the great spans are being thrown out without the aid of scaffolding. This bridge will have two main spans of 1700 feet each. The largest bridge span at present is that of the East River Bridge, New York. The main span is on the suspension principle, and is 1595 feet 6 inches wide. There are four cables, each of which contains over 5000 parallel steel wires carefully wrapped together.