Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 137,427 pages of information and 221,356 images on early companies, their products and the people who designed and built them.
WWII Halcrow's expertise was used in preparatory works at the Manod slate quarry in north Wales, used to keep treasures of the National Gallery safe from enemy air raids. His firm was also involved in designing the reinforced concrete caissons used for the Mulberry Harbours employed after D-Day in northern France, while his knowledge of dam construction was used by Barnes Wallis to help perfect the 'bouncing bomb' used in the famous Operation Chastise or Dam Buster raids of July 1943.
1944 Halcrow was knighted; the firm was renamed Sir William Halcrow and Partners