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The Encyclopaedia of Plymouth History |
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3 - THE CONSTRUCTION In January 1853 the contract for the construction of the Saltash Bridge, as it was then known, was awarded to Mr Charles J Mare of Blackwall, London, who was already well-known for his work in constructing the Britannia Bridge across the Menai Straits in north Wales. For the sum of £162,000, he agreed to complete the work in two years and four months. On Tuesday May 17th 1853 the "Plymouth Mail" reported: 'The preparatory arrangements for the commencement of this magnificent structure are being made, and we understand a very large number of men will, as soon as the workshops are completed and the necessary machinery erected, be set to work. The site was visited by Charles J Mare, Esq., the enterprising contractor on Friday last [13th], where he was met by his chief engineer, Mr Campbell, and other gentlemen connected with the works. The masonry has been entrusted to Mr Willcocks, who built the stupendous viaduct at Ivy Bridge and other points on the South Devon Railway. It is also currently reported that Mr Meredith, the representative of the late Mr Treffry of Fowey, has taken the contract for the supply of the granite for the bridge.' Unfortunately, Mr Mare soon went bankrupt and Brunel decided to construct the Bridge himself. On the afternoon of Monday July 4th 1853 the foundation for the land pier on the Cornish side was laid with full ceremony. At 3pm a procession was formed at the Town Hall, in Saltash, consisting of the Mayor, Mr W Rundle, and Corporation, Mr H Cleverton, the Town Clerk, Major Toby, Messrs Blatchley and Son, and Messrs Campbell and Braithwaite. Also in attendance was Mr J Wilcocks, the contractor for the erection of the pier. The procession was led by a brass band and the insignia of the Corporation. At the site of the ceremony, in Silver Street, the Mayor was greeted by the Recorder, Mr W Symons. Under the direction of Mr Wilcocks, the Mayor then spread the mortar beneath the limestone block, adjusted the stone and it was lowered into place amidst the cheers of the assembly. Toasts were given and drunk and the party then returned to the Town Hall for further refreshments. In the evening Mr Wilcocks entertained about fifty of the gentlemen who assisted in the ceremony at the Passage House Inn, while about 70 of his workmen were given an excellent dinner at another house in the Town. It was shortly after this event that His Royal Highness, the Prince Albert, gave his permission for the bridge to be named after him. By September of that year Brunel had taken over the once peaceful Saltash Passage, which had only in 1844 become a part of Devon, and built extensive workshops for planing, rolling, cutting, drilling and punching the huge quantity of iron that was to be used in the Bridge. There was also a blacksmith's shop containing eight forges, powered by steam fan bellows. A slipway had been constructed for use in building the large cylinders to be sunk in the river to support the Bridge. Work was already in progress making the first cylinder, which the West Briton newspaper stated measured 85 feet deep and 37 feet in diameter. This would later be sunk in position in the centre of the river where it would be pumped of water and sealed across the top. The workmen would toil inside the iron structure, supplied with air from a pump, and would construct the centre, brick, tower. A powerful set of pumps kept the water level under control. The great cylinder was floated out to the centre of the river in June 1854 and sunk on to its site, where it was allowed to settle. Steam-driven air pumps supplied air at a pressure of 35 lbs.per square inch. At first this badly affected the workmen, many being seized with cramps, faintness and even insensibility. One man died. Eventually it became possible for as many as forty labourers to work inside the cylinder at the same time. After cutting through the twelve feet of mud and large stones, the river bed was reached and this was then excavated for a further three feet until the hard body of the rock was reached. By February 1855 the bottom edge of the cylinder was standing at 87 feet 6 inches below the high-water mark. The rock was then dressed and the space filled with granite masonry to a height of seven feet. During the remainder of that year the masons continued to build the pier upwards within the protection of the cylinder. The pier was capped near the end of 1856 and on top of it were to be fitted four octagonal cast iron columns, 100 feet high, 10 feet in diameter and weighing about 100 tons each. Nothing like them had ever been seen before. They would be erected section by section beneath the great spans as they were hydraulically lifted to their final height. The machinery for carrying out the lifting operation was manufactured by Messrs Easton and Amos, of The Grove, Southwark, London, and was described in September 1857 as being 'in a forward state'. While all this was going on in the centre of the river, the two main trusses were being constructed on temporary quays at Saltash Passage. Each truss measured some 455 feet in length and the bottom of the roadway to the top of the tubes measured some 75 feet. The oval tubes themselves measured 16 feet 9 inches by 12 feet 3 inches and were constructed of wrought iron plates strengthened internally at 18 foot intervals by transverse forged wrought iron webs. At last the big day arrived and a public holiday seems to have been declared. Some twenty-thousand people descended on the Saltash and St Budeaux areas from all over Devon and Cornwall, by foot, by cart and by river steamer, to watch the first iron tube be launched and floated to the Cornish side of the river. The date was Tuesday, September 1st 1857. The truss was raised from its slipway by sinking two pontoons underneath the ends. These then rose with the tide, thus floating the span. The whole was then hauled into the centre of the river and turned through 45 degrees, to bring it over the west and centre piers. The timing had been chosen to coincide with the high tide and at just after 3.30pm, when the tide had turned, the truss sank down on to its piers. The whole process had taken a little over two hours and had been a staggering achievement of organisation, that had involved not only Mr Brunel himself but five Royal Navy vessels and 500 men. At 5pm the Band of the Royal Marines signalled the conclusion of the day by playing the National Anthem and the crowds dispersed. After the events were concluded, the Bridge was left in the care of some of the workmen. They allowed some adventurous young men to gain access to the tube and walk along the top of it. Before they would let them descend again they extracted some pennies from these people but one, Mr Edwin Hodge, the son of a builder in Mount Street, Devonport, was unable to pay so they removed the ladder, thus forcing him to attempt to reach the topmost bar. In doing so, he slipped and fell into a boat moored below, breaking his leg and sustaining other serious injuries. Mr Smith, a surgeon, from Saltash, rendered immediate assistance by dressing the wounds and binding the fractured leg and another gentleman kindly gave tewo shillings to some men to convey the man to his home. He was in a very serious condition but Mr Harrison set his fractured leg. Although it has been claimed that he died the following day, the local press reported on Saturday 12th 1857 that he was recovering well and no official record of his death has been found. With the first delicate operation out of the way, work started immediately on raising the truss to its final height of 100 feet above water level. To do this, three huge hydraulic jacks were placed under each end. Each jack alone was cable of taking the weight of the truss but as a further precaution against any accidents, each jack ram was threaded and a screw nut was run down to the body of the jack. In addition, thin timber strips were used as packing. By this means, the truss was lifted at three-foot intervals and the masonry on the western pier built up underneath. On the central pier, however, packing had to be used until the bridge had risen fourteen feet and a new section of the cast iron pillars put in. The truss was raised six feet per week. It was finally fixed in its permanent place on Wednesday July 1st 1858.
The Royal Albert Bridge with the Cornish span in position While this had been going on, the second truss was under construction at Saltash Passage and preparations for the launch were well underway. By WednesdayJuly 7th 1858, the four pontoons were in place, Government brigs and 'lumps' were moored about the river, all with warps to help control what the press described as 'the ponderous mass'. In anticipation of this being a visitor attraction, which it was, special trains were run on Friday July 9th, one from London and another from stations on the Bristol & Exeter Railway. Another special from stations on the South Devon Railway ran on the day of the event. And so it was that on Saturday July 10th 1858 the Devon span was floated out into the river and swung into place by Brunel's assistant, Mr R P Brereton. The great man himself was ill and was resting on the continent. Again, five Government vessels were on hand along with men off HMS Exmouth. Despite a high wind, the process went without a hitch and at 5pm the span was rested on its piers. The process of lifting it to its correct height began on August 9th. This work was completed in February 1859 and it was proposed to send the first locomotive across on February 26th. Amazingly, the whole construction had cost only £225,000, which compared extremely favourably with other bridges of the time. A train consisting of three carriages hauled by a South Devon Railway locomotive was run from Plymouth to Truro on Monday April 11th 1859, prior to the official inspection by Colonel W Yolland from the Board of Trade. He inspected the Cornwall Railway as a whole over three days, ending with tests on the Royal Albert Bridge on April 20th. Two tests were carried out, the second using a train of two locomotives plus twenty loaded trucks. He also tried running the train over the Bridge at 30mph but the resulting vibration was such that he was unable to record the results. It is likely that the subsequent speed restriction applied to trains crossing the bridge, 15mph, was imposed immediately as a consequence. All was now ready for the grand Opening Day.
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