Bridging the Forth

“If I were to pretend that the designing and building of the Forth Bridge were not a source of present and future anxiety to all concerned, no engineer of experience would believe me. Where no precedent exists, the successful engineer is he who makes the fewest mistakes.” Benjamin Baker.

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1887

One specially noteworthy feature about this in-all-respects-wonderful bridge is that the cantilevers …. have been built steadily out from the piers without any even temporary support from below. These mighty segments of steel arches have been built out into the air—into empty space…. Day by day fresh sections have been added on, the workmen perched on any convenient projection performing their duties at a giddy height above the flowing water. There was no scaffolding. Steam cranes were run on tramways out to the end of the finished portion of the cantilevers and then the steel plates to be next riveted on were hauled up from punts floating in the estuary below.

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May 1888

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August 1888

It is a curious thing that there is seldom so much wind at the top of the bridge as lower down. When it was too strong to work on the lower members, the workmen used to go to the top for shelter. “I went up on a breezy day this week,” writes a contributor, “and on the platform on the top of the cantilever pillars, 570 feet high, there was scarcely a breath of air. So soon as you get above the cliffs which confine the Firth at its narrowest point, the wind distributes itself, and what is a fresh breeze at the water’s level is only a faint zephyr at the top of the structure. It is a pity that when the bridge is completed the hoists which carry you soaring up, with only a couple of wires to steady the cage, must be removed, for a charge to see the view might produce a useful revenue.

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Early 1889

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June 1889

The greatest engineering work of its kind, and perhaps of any kind, the world has yet seen completed one of its stages on October 10th [1889], when the south cantilevers of the Forth Bridge—those between Queensferry and Inchgarvie—were successfully joined. Advantage was taken of the fine day to carry out this interesting and delicate operation, which had been delayed by recent cold and storms. At the last moment there was a gap of three-quarters of an inch between the bolt holes, but by means of hydraulic jacks and by lighting a fire of naphtha waste in the trough of the girder, the necessary expansion was secured. Mr. Arrol struck the first bolt, and the rest were immediately thereafter driven home.

It is of interest to record that the three engineers who created the Forth Bridge are all self made men. Sir John Fowler, who is in his 73rd year, was born at Sheffield. To him London owes its under ground railway system. Sir Benjamin Baker, although still young, has carried out important works in Canada and at the Cape. Sir William Arrol was originally a piercer in a Paisely cotton mill, and when he received the freedom at Ayr the other week he mentioned that 30 years back he entered the same town a poor blacksmith in search of employment. In 1868 he started in business in Dalmarnock road, Glasgow, with a capital of £85 saved from his wages. With this he bought an engine at £18, and a boiler at £35. For some time his staff consisted of himself and a workman. Seventeen years passed away and his staff numbered 4300, engaged on the Forth Bridge.

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1890

“It is now seven years, or nearly seven years, since the foundations of this bridge were commenced, and until two years ago we had to endure not only the legitimate anxieties of our duties, but the attacks and evil predictions which are always directed on those who undertake engineering work of novelty or exceptional magnitude. When I was carrying out the Metropolitan Underground Railway I was told it never could be made, that if it was made it never could be worked, and that if it was worked no one would travel by it. M. De Lesseps, of the Suez Canal, was warned that if the canal was made it would be quickly filled up with desert sand, and the harbor of Port Said would be filled with Nile mud….. It is very curious to watch the manner of retreat of these prophets of failure when results prove they have been mistaken”. Sir John Fowler at the opening ceremony, 4th March 1890.

Text has been edited from various newspapers of the time. Images were produced by Valentines. The letter card that provided the first five was “bought at the Forth Bridge from Miss Ewart’s Ferry Tea Rooms”. The ferries continued in business until the road bridge opened in 1964. A third bridge was added in 2017.

The Forth (Rail) Bridge still carries up to 200 trains a day.

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