To produce uranium metal, they tried reducing uranium oxide with hydrogen, but this did not work. They then investigated a process (now known as the Ames process) originally developed by J. C. Goggins and others at the University of New Hampshire in 1926. This involved mixing uranium tetrachloride and calcium metal in a calcium oxide-lined steel pressure vessel (known as a "bomb") and heating it. They were able to reproduce Goggin's results in August 1942, and by September, the Ames Project had produced a ingot. Starting in July 1943, Mallinckrodt, Union Carbide, and DuPont began producing uranium by the Ames process, and Ames phased out its own production by early 1945. As a result, the Ames Laboratory never moved to Chicago, but Spedding was present at the University of Chicago on 2 December 1942, to witness the first controlled nuclear chain reaction in Fermi's Chicago Pile-1.