"Ultra and Magic are more symmetrical than not. In each case, a belligerent Power has developed a machine cypher which it considers to be perfectly unbreakable. In each case, an allied Power has in fact broken that cypher. In America, Dr. Schoen and his team broke Indigo and devised the Magic machine. Here, it was Dr. Knox’s team that broke Enigma and devised the Bombe. The leading light here seems to have been Dr. Turing. The leading light with you chaps was Dr. Schoen, who is, as you said, under the weather. But he holds you up as comparable to Turing, Commander Waterhouse."