A. M. Hamilton - Callender-Hamilton Bridge

Callender-Hamilton Bridge

During the construction of the road, Hamilton became aware of the need for strong, adaptable bridges with components that could easily be transported and erected in remote and/or difficult terrain. With British Insulated Callenders Cables, now Balfour Beatty Power Networks Ltd, he designed the Callender-Hamilton bridge system, the income from which helped support his family. The parts of the bridge were bolted together like a Meccano set, and it was popular with the British Army away from the battle front. The failure of the First World War Inglis bridge led to the development of the Bailey bridge. Hamilton successfully claimed to the Royal Commission on Awards to Inventors that the 'Bailey' bridge had breached his patent. Because the 'Bailey' used a pin joining system similar to that used in a Martel design, Hamilton told the Commission the bridge should be called a 'Martel Mk2'.

The War Office, in 1936, gave Hamilton 4000 pounds for the free non-civil use of his Unit Construction bridge. In 1954 the Commission gave him 10000 pounds for the bridges used in S.E.A.C. in India.

In 1955 Hamilton told the Commission that Martel deserved more than the 12000 pounds that Bailey got, Martel was given 500 pounds.