Page:Cassier's Magazine Volume XV.djvu/27

Rh hand. The first portion of the cantilevers was erected from small overhanging stages by the cranes resting on them. A large platform somewhat similar to that used in the main pier was then adopted, and was raised by somewhat similar means to the level of about 180 feet above high water. These platforms were not carried further, nor were any more of a similar nature used, as it was afterwards found that the work could be much more conveniently carried

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out from the cranes on the internal viaduct on which the railway now runs, and from those placed on the top member of the superstructure. These cranes, and the small platforms attached to the principals that were being built, offered a more convenient method, which was adopted, for the erection of the remainder of the cantilevers.

After the cantilevers were completed, the next work taken in hand was the erection of the central girders. These were also built by overhanging stages, and special means were taken in connection with joining them up in the centre, so that, when they met, the bottom boom was first connected, and certain of the temporary connections were thereafter relieved, until the top booms were connected and the remaining temporary connections cut away and the girder allowed to rest on the ends of the two adjacent cantilevers.

After the completion of the central girders, little remained to be done to finish the structure for the opening of traffic, and on March 4, 1890, this ceremony was performed by the Prince of Wales. At a banquet which followed the opening, and which was attended by many men of note in the railway world, the Prince of Wales announced that the Queen had been pleased to confer the honour of knighthood upon William Arrol for the great ability he had shown in carrying out this great undertaking.

Shortly before the completion of the Forth Bridge the firm of Sir William Arrol & Co. undertook the erection of all the main viaducts and a good many of the swing-bridges for the Manchester