On the road from Berwick to Edinburgh, the Peas bridge erected over a deep dingle, is a bold work. It consists of four arches; the largest span is 55 feet, and the height of the bridge is 124 feet. The architect was fir David Henderson of Edinburgh.
A large arch has been built at Aberdeen also over a dingle, through which there runs a small rill called the Den Burn ; it forms apart of an improved approach to the city from the southwards. The magistrates had in the year 180 begun to construct abridge of three small arch Cs, and had laid the foundations of the abutments and piers for that purpose, under the direction of their then super intendant of city works, Mr Fletcher, when Mr Telford the engineer passing that way on the service of govern ment, was desired by the magistrates to examine their intended bridge. On considering the excellent gra nite stone which was used, he prevailed with them to abandon the scheme of having three arches. At their desire he gave a plan of one arch of 150 feet span, being larger than any stone arch in Britain, and other wise containing many singular features calculated to prove what could be performed with Aberdeen granite. But however desirous the magistrates were to exhibit the excellency of their favourite material, the expense of this plan much exceeded their funds. Mr Telford afterwards made a simpler design; but in order to save some masonry of the abutments which had already been executed, they got their inspector of the city works to reduce the span to 130 feet, of which dimensions it has been executed. The rise is 29 feet, and breadth across the soffit 43 feet. It is still a magnificent arch, though of smaller span than that of Mr Edwards over the Taaf. The difficulty attending the construction of a large arch here, was much lessened by its being placed on dry land.
A much more arduous task has been accomplished upon the river Dee, at Tongueland, near Kirkcudbright, where there is about 10 feet of water in the lowest state of the river, above which the ordinary spring tides rise 16 feet, and where of course, for a large arch, a trussed centre was required. The design was given by Mr Telford ; it is 118 feet span, and the rise or versed sine 38 feet. The spaces between the large arch and the rocky banks upon which it abuts, instead of being filled by earthen embankments, are occupied by small arches raised upon slender piers. The whole has a bold effect,
especially during the flux and reflux of a high spring tide immediately under the bridge, when agitated by a strong westerly wind, and accompanied by a great land flood, tumbling down a rocky channel at some distance above it. See Plate LXXXVII.
A large bridge has been lately built over the river Spey, near Gordon castle, at Fochabers. It consists of four arches ; the two middle ones are each 95 feet span, and the breadth over the parapets is 21 feet 6 inches. There being an even number of arches, a pier is brought into the middle of the river, and the architecture of the facade is feeble ; still the structure does credit to the architect and builder, Mr G. Burn.
The finest bridge in Scotland is that which has just been built by the duke of Athol, over the river Tay, at Dunkeld. There are five large arches and two small er land arches; the middle arch is 90 feet span, and rises 30 feet, the width over the parapets is 27 feet 6 inches. The facade has castellated turrets over the piers and abutments ; the outlines of the parapets and roadway is a curve only sufficient to carry off the wa ter ; the approaches to the bridge, the duke has render ed very complete ; and the whole forms a feature, suitable to the magnificent scenery which surrounds Dunkeld. The design for this bridge was made by Mr Telford. It was executed under his directions, and finished in 1809.
From the foregoing statements, it is evident that the progress of bridge building in Britain has of late years been great ; but the effects, though considerable, have been distant and unconnected. Perhaps, however, the greatest and most regular scheme for opening the general intercourse through a great extent of country, that has ever been voluntarily undertaken by a free people, was that which originated in 1802. Previous to this, the northern districts of Scotland, although in sundry parts intersected by military roads, were very imperfectly opened ; for these had been hastily con structed, and frequently ill fitted for the purposes of civil life.