And he had made me go through his Saturday evening's programme again--his inspection of the Hogarths, his unusual wakefulness, the hour at which he had gone upstairs. Only for a few moments on the Sunday morning had he seemed dimly to surmise that something of the last importance might have happened to him during the hours of darkness. He had then forgotten all about it. Nevertheless, would not his next rejuvenation date, not the moment of the fact itself, _but from that of the beginning of his realisation of it_? No--no--I was not quite right even yet. Even _that_ moment of wild fear, so quickly gone again, was not the moment I sought. Even after _that_ he might to all appearances have remained twenty-nine for some hours longer. For his change happened while he slept, and I had not reckoned with that sleep that must come in between. His next sleep had been, not in my house, but in Trenchard's loft. _Monday morning, July 5th_, had been his new starting-point, and that day he had disappeared. You have now all the material dates that I had. You know that in comparatively uneventful, unexciting circumstances he could go back four years in a night. And I have told you of the headlong rôle Julia Oliphant had taken upon herself. How old, then, was Derwent Rose when he woke up in Trenchard's rooms on the morning of Monday, July 5th, 1920? Twenty-five? Twenty? Or sixteen and already dead? II I now turn to that portion of the diary that seemed to confirm my impression that he had gone to France. Both his memories, "A" and "B," appeared so far to be functioning normally. In order to ascertain this he had applied a number of ingenious tests to himself. But it immediately struck me that while all his "A" (or Age) notes were written in English, all those in the "B" (or Boyhood) direction were in French. And not only was the language French. The illustrations and incidents were French in character also. Thus, he wrote in English: "Have been trying to see how much of _Esau_ I can remember without looking at the book"; but of something that had once happened in Marseilles I read: "Je tâche de me débrouiller de ces souvenirs-ci." There might have been purpose in this alternation of the two languages, but I was more inclined to think that he had done it purely instinctively. When a man speaks a language as Derwent Rose spoke French he finds a pleasure in the mere exercise of his attainment. France had always attracted him, he had not unlimited money at his disposal, and mere considerations of ordinary time (an intensely special thing to him) might preclude his getting more than a few hours' journey away. Anyway, with one thing and another, I had chanced it, and guessed that somewhere on the north coast of France would find him. "And you're going over there to stay with the Airds," Julia mused. "Then there's just a possibility----" "Oh, the whole coast will be swarming with English by the end of the month." "Still----"