In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Britannia Bridge like this:
BRITANNIA BRIDGE, a tubular viaduct over the Menai strait, between Carnarvon and Anglesey; on the line of the Chester and Holyhead railway, 1 mile SW of the Menai bridge, and 2 W by S of Bangor station. It was designed by Mr. Robert Stephenson; was commenced in 1846, and opened in 1850; and cost £621,865. The channel, at its site, is 1,100 feet wide; is swept by a very rapid tide, ordinarily rising 20 feet; and is beset, in the middle, by a rock, called the Britannia rock, which is bare to the height of 10 feet at low water, and covered to the same height by full tide. ...
This rock gave name to the bridge, and afforded a main facility for constructing it. The bridge consists of two abutments at the ends; two towers, 230 feet distant from the abutments; a central tower on the Britannia rock, 460 feet distant from the other towers; and two vast wrought iron tubes, or tunnels, placed side by side, and resting on the abutments and the towers. Each abutment is 176 feet long; each of the nearer towers, 32 feet broad, the central tower, 45½ feet broad; and the total roadway, 1,841 feet long. The approaches are ornamented by two colossal Egyptian statues of lions couchant, each 25½ feet long, and 12 feet 8 inches high; the two nearer towers measure 62 feet by 52½ at the base, taper to 55 feet by 32 at the top, and rise 190 feet above high-water level; the central tower has similar measurements of base and taper, and rises 230 feet from its foundation on the rock; and the bottom of the roadway is elevated 101 feet above the level of high water. The two tubes or tunnels consist of plates, rivets, and angle-irons; are flat in the bottom, and arched in the top; have an exterior height increasing from 22¾ feet at the ends to 30 feet in the centre; are four feet lower in the interior than in the exterior, and each 14 feet wide; and possess a total computed weight of about 10,000 tons. The trains going W invariably pass through one line of tube; and those going E invariably pass through the other. The bridge, as seen from a distance, looks very tame; and even as seen close at hand, possesses none of the picturesqueness of its beautiful neighbour the suspension bridge; yet, on close inspection, impresses the mind with a sense of vastness and power.
A Vision of Britain through Time includes a large library of local statistics for administrative units. For the best overall sense of how the area containing Britannia Bridge has changed, please see our redistricted information for the modern district of the Isle of Anglesey. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Britannia Bridge and units named after it.
GB Historical GIS / University of Portsmouth, History of Britannia Bridge, in The the Isle of Anglesey and Caernarvonshire | Map and description, A Vision of Britain through Time.
Date accessed: 24th May 2013
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