雙語暢銷書《艾倫圖靈傳》第6章:連接兩個世界(3)大綱
They were all spy-conscious in Washington now, but such anecdotes apart, the central event of Alan's visit was the breakthrough back into the U-boat Enigma.
This was achieved without the possession of faster Bombes; it depended upon a precarious thread of luck, ingenuity, and a German blunder.
在更高速的炸彈機出現之前，這種謎機就已經被破解了，這是依靠一系列的運氣和創造力，還有德國的失誤。It went back to the weather signals that in mid-1941 had given them an almost unfairly simple crib each day, thanks to the fact that they were transmitted both in the Enigma, and in the special meteorological cipher.
此事要從1941年中期的氣象信號說起，這些信號是用謎機和一種特殊的氣象密碼同時發送的，所以每天都能給布萊切利提供便捷而清晰的"牀位"。
But early in 1942 a change in the system had denied this method to Hut 8. Not until the U-boat capture of 30 October could it be regained.
但在1942年初期，這個系統發生了一點改變，於是8號營房的這個方法失效了。直到10月30日他們繳獲了一艘潛艇，才重新有辦法取得牀位。This gave them the cribs, but the difficulty remained that it would take three weeks to work through all the rotor settings, just for one day's traffic.
但仍然有一個困難是，推導一天的盤位需要三個星期。Here, however, they were saved by a German blunder which, in effect, threw away all the advantage that the fourth wheel offered.
然而，德國的一次愚蠢的失誤再次拯救了他們，這次失誤使第四輪盤的優勢完全泡湯。For the weather reports, and other routine short signals, the U-boats used their Enigma with the fourth wheel in 'neutral' position, thus reducing the cryptanalysts' problem to the one they had mastered in 1941.
U型潛艇在發送氣象報告和一些例行信號時，只使用了三個轉盤，這就使問題變成了布萊切利在1941年就已經解決的老問題。This in itself was not fatal for Germany; the greater mistake lay in the fact that the three rotor settings used for the weather reports were also used for all the other traffic of the day.
對德國來說，這本身不是致命的，更嚴重的錯誤在於，當他們使用四個轉盤發送其它通信時，前三個轉盤的盤位設定仍然不變。For this the analysts now needed only to work through 26 possibilities for the fourth wheel, rather than the 26 × 336 × 17576 possibilities that would otherwise have been the case.
因此，分析人員只需要檢查第四轉盤的26種盤位，而不是本來應該需要檢查的26×336×17576種。As a result of this slip, Hut 8 was able to supply decrypted messages from 13 December.
這個失誤的結果是，8號營房從12月13日開始，又能正常工作了。They had weeks in which nothing worked out.
他們已經好幾個星期沒有產出信息了，But it was sufficiently copious a flow of information for the Tracking Room in the OIC to have by 21 December a clear idea of the location of all eighty-four U-boats at large in the North Atlantic.
但到了12月21日，他們可以清楚地獲知北大西洋全部84艘潛艇的方位，這對於作戰情報中心的追蹤室來說，已是一桌足夠豐盛的大餐了。And this time Hut 8 was not alone. In Washington, Alan Turing was indoctrinating the American analysts into all their methods.
8號營房這次不是獨自戰鬥，艾倫·圖靈正在華盛頓，把所有的方法教給美國分析人員。Now, when the rotor settings were discovered, they were passed back and forth across the Atlantic, the analysts beginning to communicate directly as indeed the two tracking rooms were also doing.
現在，雙方破解出來的盤位設定在大西洋上空傳遞着，兩國的分析人員展開了密切合作，雙方的追蹤室亦是如此。
