They had caught a small break, though. When a Japanese plane crashed in Burma, the British captured some message templates—a template is a blank form with some code groups filled in to speed the process—and sent them to Arlington Hall, which had them in its possession by late January 1943. Wilma and Ann began having quiet conversations about how best to use this material. They agreed that chaining differences was “silly” and that it made more sense to use the templates and the bits of information they contained. They had a couple of other tools as well. They had received a report from
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