1. Matters were not helped by the eminent theorist Coulomb, who refused to believe in buckling. He stated that the strength of columns depended on cross-sectional area alone and declared that masonry columns a quarter of a mile high were quite feasible. C. S. Gillmor, Coulomb and the Evolution of Physics and Engineering in 18th Century France (Princeton, 1971), p. 100.
2. Russian Iron Bridges to 1850
3. The author's thanks are due to R. W. Rennison for discovering the Alnwick bridge and providing slides and notes, and to the Duke of Northumberland for access to two bridge drawings in the archives of Syon House. Both of the latter appear to be unused single-span designs for the existing three-span bridge at Syon. One (unsigned and undated) is 70 ft long with arched wrought-iron brackets (21/2 in square bar) supporting iron longitudinal deck beams 4 in x 21/2 in. The other (signed James Wyatt, 1790) is 80 ft long with similar brackets, but supports timber longitudinal deck beams 12 in deep.
4. The Evolution of Iron Bridge Trusses to 1850