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The bridge leaves Edinburgh at South Queensferry and arrives in Fife at North Queensferry. Its construction began in 1882 and took 8 years to complete.
Until 1917, when the Quebec Bridge was completed, the Forth Bridge had the longest single cantilever bridge span in the world, and it still has the world's second-longest single span. The bridge and its associated railway infrastructure is owned by Network Rail Infrastructure Limited. It is considered an iconic structure and a symbol of Scotland.
Prior to the construction of the bridge, ferry boats were used to cross the Firth.[1] In 1806, a pair of tunnels, one for each direction, was proposed, and in 1818 James Anderson produced a design for a three-span suspension bridge close to the site of the present one.[2] Calling for approximately 2,500 tonnes (2,500 long tons; 2,800 short tons) of iron, Wilhelm Westhofen said of it "and this quantity [of iron] distributed over the length would have given it a very light and slender appearance, so light indeed that on a dull day it would hardly have been visible, and after a heavy gale probably no longer to be seen on a clear day either."[3]
Thomas Bouch designed for the Edinburgh and Northern Railway a roll-on/roll-off railway ferry between Granton and Burntisland that opened in 1850, which proved so successful that another was ordered for the Tay.[4] In autumn 1863, a joint project between the North British Railway and Edinburgh and Glasgow Railway, which would merge in 1865, appointed Stephenson and Toner to design a bridge for the Forth, but the commission was given to Bouch around six months later.[5]
It had proven difficult to engineer a suspension bridge that was able to carry railway traffic, and Thomas Bouch, engineer to the North British Railway (NBR) and Edinburgh and Glasgow Railway, was in 1863-1864 working on a single-track girder bridge crossing the Forth near Charlestown, where the river is around 2 miles wide, but mostly relatively shallow.[5][6] The promoters, however, were concerned about the ability to set foundations in the silty river bottom, as borings had gone as deep as 231 feet (70 m) into the mud without finding any rock, but Bouch conducted experiments to demonstrate that it was possible for the silt to support considerable weight. Experiments in late 1864 with weighted caissons achieved a pressure of 5 tons/ft2 on the silt, encouraging Bouch to continue with the design. In August 1865, Richard Hodgson, chairman of the NBR, proposed that the Company invest GB£18,000 to try a different kind of foundation, as the weighted caissons had not been successful.[8] Bouch proposed using a large pine platform underneath the piers, 80 by 60 by 7 feet (24.4 × 18.3 × 2.1 m) (the original design called for a 114 by 80 by 9 feet (34.7 × 24.4 × 2.7 m) platform of green beech) weighed down with 10,000 tonnes (9,800 long tons; 11,000 short tons) of pig iron which would sink the wooden platform to the level of the silt. The platform was launched on 14 June 1866 after some difficulty in getting it to move down the greased planks it rested on, and then moored in the harbour for six weeks pending completion.The bridge project was aborted just before the platform was sunk as the NBR expected to lose "through traffic" following the amalgamation of the Caledonian Railway and the Scottish North Eastern Railway. In September 1866, a Committee of Shareholders investigating rumours of financial difficulties found that accounts had been falsified, and the chairman and the entire board had resigned by November. By mid-1867 the NBR was nearly bankrupt, and all work on the Forth and Tay bridges was stopped.
Bouch's proposed bridge (top) along with other proposals on the same principle
The North British Railway took over the ferry at Queensferry in 1867, and completed a rail link from Ratho in 1868, establishing a contiguous link with Fife. Interest in bridging the Forth increased again, and Bouch proposed a stiffened steel suspension bridge on roughly the line of the present rail bridge in 1871, and after careful verification, work started in 1878 on a pier at Inchgarvie.
After Tay Bridge collapsed in 1879, confidence in Bouch dried up and the work stopped.The public inquiry into the disaster, chaired by Henry Cadogan Rothery, found the Tay Bridge to be "badly designed, badly constructed and badly maintained," with Bouch being "mainly to blame" for the defects in construction and maintenance and "entirely responsible" for the defects in design.
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After the disaster, which occurred in high winds for which Bouch had not properly accounted, the Board of Trade imposed a lateral wind allowance of 56 lbs/ft2.Bouch's 1871 design had taken a much lower figure of 10 lbs/ft2 on the advice of the Astronomer Royal, although contemporary analysis showed it would likely have stood, but the engineers stated that "we do not commit ourselves to an opinion that it is the best possible" [design]. Bouch's design was formally abandoned on 13 January 1881, and Sir John Fowler, W. H. Barlow and T. E. Harrison, consulting engineers to the project, were invited to give proposals for a bridge.
The Bill for the construction of the bridge was passed on 19 May 1882 after an eight day enquiry, the only objection being from rival railway companies. On 21 December of that year, the contract was let to Sir Thomas Tancred, Mr. T. H. Falkiner and Mr. Joseph Philips, civil engineers and contractor, and Sir William Arrol & Co..Arrol was a self-made man, who had been apprenticed to a blacksmith at the age of thirteen before going on to have a highly successful business. Tancred was a professional engineer who had worked with Arrol before, but he would leave the partnership during the course of construction.
Offices and stores erected in connection with Bouch's bridge by Arrol were taken possession of for the new works, and would be expanded considerably over time.An accurate survey was taken by Mr. Reginald Middleton, to establish the exact position of the bridge and allow the permanent construction work to commence.
The old coastguard station at the Fife end had to be removed to make way for the north-east pier.The rocky shore was levelled to a height of 7 feet (2.1 m) above high water to make way for plant and materials, and huts and other facilities for workmen were set up further inland.
The preparations at South Queensferry were of a much more substantial character, and required the steep hillside to be terraced. Wooden huts and shops for the workmen were put up, as well as more substantial brick houses for the foremen and tenements for leading hands and gangers. Drill roads and workshops, as well as a drawing loft 200 by 60 feet (61 by 18 m) to allow full size drawings and templates to be laid out. A cable was also laid across the Forth to allow telephone communication between the centres at Queensferry, Inchgarvie, and Fife, and girders from the collapsed Tay Bridge were laid across the railway to the west in order to allow access to the ground there.Near the shore a sawmill and cement store were erected, and a substantial jetty around 2,100 feet (640 m) long was started early in 1883, and extended as necessary.Sidings were built to bring railway vehicles among the shops, and cranes set up to allow the loading and movement of material delivered by rail.
In April 1882, construction of a landing stage at Inchgarvie commenced. Extant buildings, including fortifications built in the 15th century, were roofed over to increase the available space, and the rock at the west of the island was cut down to a level 7 feet (2.1 m) above high water, and a seawall was built to protect against large waves In 1884 a compulsory purchase order was obtained for the island, as it was found that previously available area enclosed by the four piers of the bridge was insufficient for the storage of materials. Iron staging reinforced wood in heavily used areas was put up over the island, eventually covering around 10,000 square yards (8,400 m2) and using over 1,000 tonnes (980 long tons; 1,100 short tons) of iron.
The bridge uses 55,000 tonnes (54,000 long tons; 61,000 short tons) of steel and 140,000 cubic yards (110,000 m3) of masonry. Many materials, including granite from Aberdeen, Arbroath rubble, sand, timber, and sometimes coke and coal, could be taken straight to the centre where they were required. Steel was delivered by train and prepared at the yard at South Queensferry before being painted with boiled linseed oil before being taken to where it was needed by barge. For a time a paddle steamer was hired for the movement of workers, but after a time it was replaced with one capable of carrying 450 men, and the barges were also used for people carrying. Special trains were run from Edinburgh and Dunfermline, and a steamer ran to Leith in the summer.
The bridge was completed in December 1889, and load testing of the completed bridge was carried out on 21 January 1890. Two trains, each consisting of three heavy locomotives and 50 wagons loaded with coal, totalling 1,880 tons in weight, were driven slowly from South Queensferry to the middle of the north cantilever, stopping frequently to measure the deflection of the bridge. This represented more than twice the design load of the bridge: the deflection under load was as expected.[26] A few days previously there had been a violent storm, producing the highest wind pressure recorded to date at Inchgarvie, and the deflection of the cantilevers had been less than 25 mm (1 in). The first complete crossing took place on 24 February, when a train consisting of two carriages carrying the chairmen of the various railway companies involved made several crossings. The bridge was opened on 4 March 1890 by the Prince of Wales, later King Edward VII, who drove home the last rivet, which was gold plated and suitably inscribed. The key for the official opening was made by Edinburgh silversmith John Finlayson Bain, commemorated in a plaque on the bridge.
At its peak, approximately 4,600 workers were employed in its construction. Wilhelm Westhofen recorded in 1890 that 57 lives were lost; but in 2005 the Forth Bridge Memorial Committee was set up to erect a monument to the briggers, and a team of local historians set out to name all those who died.[28] As of 2009, 73 deaths have been connected with the construction of the bridge and its immediate aftermath.[29] It is thought that the figure of 57 deaths excluded those who died working on the approaches to the bridge, as those parts were completed by a subcontractor, as well as those who died after the Sick and Accident Club stopped. Of the 73 recorded deaths, 38 were as a result of falling, 9 of being crushed, 9 drowned, 8 struck by a falling objec, 3 died in a fire in a bothy, 1 of "caisson disease", and the cause of five deaths is unknown.
The Sick and Accident Club was founded in the summer of 1883, and membership was compulsory for all contractors employees. It would provide medical treatment to men and sometimes their families, and pay them if they were unable to work.The Club also paid for funerals within certain limits, and would provide grants to the widows of men killed or the wives of those permanently disabled.Eight men were saved from drowning by rowing boats positioned in the river under the working areas.
In the First World War British sailors would time their departures or returns to the base at Rosyth by asking when they would pass under the bridge.[38] This practice continued at least up to the 1990s. In both wars the anchorage at Rosyth extended eastwards beyond the bridge.
A German photograph allegedly taken during the raid
The first German air attack on Britain in the Second World War took place over the Forth Bridge, six weeks into the war, on 16 October 1939. Although known as the "Forth Bridge Raid", the bridge was not the target and not damaged. In all, 12 German Junkers Ju 88 bombers led by two reconnaissance Heinkel He 111s from Westerland on the island of Sylt, 460 miles (400 nmi; 740 km) away, reached the Scottish coast in four waves of three.[39] The target of the attack was shipping from the Rosyth naval base in the Forth, close to the bridge. The Germans were hoping to find HMS Hood, the largest capital ship in the Royal Navy. At this time, the Luftwaffe's rules of engagement restricted action to targets on water and not in the dockyard. Although HMS Repulse was in Rosyth, the attack was concentrated on the cruisers HMS Edinburgh and HMS Southampton, the carrier HMS Furious and the destroyer HMS Jervis.[40] Three ships were damaged in the raid: the destroyer HMS Mohawk and two cruisers, HMS Southampton and HMS Edinburgh. Sixteen Royal Navy crew died and a further 44 were wounded, although this information was not made public at the time.[41]
Spitfires from RAF 603 "City of Edinburgh" Squadron intercepted the raiders and during the attack shot down the first German aircraft downed over Britain in the war.[42] One bomber came down in the water off Port Seton on the East Lothian coast, and another off Crail on the coast of Fife. After the war it was learned that a third bomber had come down in Holland as a result of damage inflicted in the raid. Later in the month, a reconnaissance Heinkel 111 crashed near Humbie in East Lothian and photographs of this crashed plane were, and still are, used erroneously to illustrate the raid of 16 October, thus sowing confusion as to whether a third aircraft had been brought down.Members of the bomber crew at Port Seton were rescued and made prisoners-of-war. Two bodies were recovered from the Crail wreckage and, after a full military funeral with firing party, were interred in Portobello cemetery, Edinburgh. The body of the gunner was never found.A propaganda film, "Squadron 992", made by the GPO Film Unit after the raid recreated the raid and conveyed the false impression that the main target was the bridge.
A 1913 Railway Clearing House Junction Diagram showing the Forth Bridge Railway (red) and neighbouring lines of the North British Railway (blue)
Prior to the opening of the bridge, the North British Railway (NBR) had lines on both sides of the Firth of Forth between which trains could not pass except by running at least as far west as Alloa and using the lines of a rival company. The only alternative route between Edinburgh and Fife involved the ferry at Queensferry, which was purchased by the NBR in 1867. Accordingly, the NBR sponsored the Forth Bridge project which would give them a direct link independent of the Caledonian Railway;[46] a conference at York in 1881 set up the Forth Bridge Railway Committee, to which the NBR contributed 35% of the cost. The remaining money came from three English railways, who ran trains from London over NBR tracks: the Midland Railway, to which the NBR connected at Carlisle and which owned the route to London (St Pancras), contributed 30%, whilst the remainder came equally from the North Eastern Railway and the Great Northern Railway, who between them owned the route between Berwick-upon-Tweed and London (King's Cross), via Doncaster. This body undertook to construct and maintain the bridge.
In 1882 the NBR were given powers to purchase the bridge, which it never exercised. At the time of the 1923 Grouping, the bridge was still jointly owned by the same four railways,and so it became jointly owned by these companies' successors, the London Midland and Scottish Railway (30%) and the London and North Eastern Railway (70%).[50] The Forth Bridge Railway Company was named in the Transport Act 1947 as one of the bodies to be nationalised and so became part of British Railways on 1 January 1948.[51] Under the Act, Forth Bridge shareholders would receive £109 of British Transport stock for each £100 of Forth Bridge Debenture stock; and £104-17-6d (£104.87½) of British Transport stock for each £100 of Forth Bridge Ordinary stock.
Network Rail is in the early planning stages to add a visitor centre to the bridge, which would include a viewing platform on top of the North Queensferry side, or a bridge climbing experience to the South Queensferry side.
The approach to the bridge from Dalmeny Station
The bridge has a speed limit of 50 miles per hour (80 km/h) for high-speed trains and diesel multiple units, 40 miles per hour (64 km/h) for ordinary passenger trains and 30 miles per hour (48 km/h) for freight trains. The route availability code is RA8, but freight trains above a certain size must not pass each other on the bridge.
Up to 190–200 trains per day crossed the bridge in 2006. The Forth Bridge needs constant maintenance and the ancillary works for the bridge include not only a maintenance workshop and yard but a railway "colony" of some fifty houses at Dalmeny Station. The track on the bridge is of "waybeam" construction: 12 inch square baulks of timber 6 metres long are bolted into steel troughs in the bridge deck and the rails are fixed on top of these sleepers. Prior to 1992 the rails on the bridge were of a unique "Forth Bridge" section.
"Painting the Forth Bridge" is a colloquial expression for a never-ending task, coined on the erroneous belief that at one time in the history of the bridge repainting was required and commenced immediately upon completion of the previous repaint.Such a practice never existed, as weathered area were given more attention, there was a permanent maintenance crew.
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