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Rh pier, but that it is set back 5 ft. to the inside of the pier, the centres between the vertical columns being, therefore, 10 ft. less than the distance between piers. This was done with a view to the better distribution of the downward stresses, which are greatest in the bottom members of the cantilevers; and as it was for structural reasons not practicable, or, at any rate, expedient, to bring the centres of the main compression members to one point, it was thought best to make the distribution as even as possible.

To return again to the upper bedplate. This was put together with all its longitudinal I girders and transverse cell-plates upon the pier, resting upon supports similar to those used for the lower bedplates. The same machine was used for rivetting the bottom portions of the plate, and all rivets were countersunk on the under side, while for the upper end a bent snap had to he used in order to get round the flanges of the girders and cell-plates. On the under side all projecting rivet-heads had to be removed as before. The key-plates were now placed in the recess of the lower plate to ascertain whether they fitted and had good