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for computing. When a daily wheel change was introduced in July, 1944, wheel-breaking became a normal part of the Newmanry's work, and about 18 Wrens a shift were employed in computing and (eventually) 3 Colossi on the later wheel-breaking processes. 'Key-breaking', i.e. finding the wheels by statistical methods from key found from depths, was closely allied to ordinary wheel-breaking, and undertaken in collaboration with the Testery.
'Cribbing' as a method of obtaining wheels, was begun in June, 1944. Since this required two message tapes to be run against each other, the use of Robinson was essential, and in view of the troubles on the old Robinson a new model was designed by DR. COOMBES and MR. CHANDLER of Dollis Hill; two of them had been completed by 8th May, 1945.
(g) Tape-making machinery.
The prototypes of Garbo and Miles were introduced towards the end of 1943.