Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 147,398 pages of information and 233,518 images on early companies, their products and the people who designed and built them.
The first electrically-powered swing bridge.
The contractors for the steelwork were S.A. des Ateliers de Construction de Hal, of Hal, near Brussels, Belgium. 
The bridge was described in great detail in 'The Engineer' 1917 (26 January, 2, 9 & 12 February).