"Midnight is, with certain exceptions, M. Platzoff's fixed hour for going to bed. My instructions are to go every night at twelve precisely; to give a low treble knock on the door of the smoke-room, and then with the aid of the pass-key to go in. I then relieve M. Platzoff of his pipe, generally a large Turkish hookah; accompany him to his dressing-room, and take his instructions for the morning. After that I put out the lights, and then my duties for the day are over. "But once, sometimes twice a week, M. Platzoff is in the habit of smoking opium, or some drug so much like it that I cannot tell the difference. Whatever it may be, he smokes it till he falls into a sort of trance in which he is unconscious of everything going on around him. My instructions are that when, on entering the smoke-room at midnight, I find him in such a trance, not to disturb him, but to watch by him till I see certain signs that the trance is abating. As soon as these signs show themselves, I lift M. Platzoff bodily up and carry him to bed, and so leave him till morning. One of Cleon's most important duties was the charging of M. Platzoff's pipe when the latter was going to have one of his opium séances; but that is too nice an operation to be entrusted to my unskilled hands, and in the absence of Cleon is, I presume, gone through by the Russian himself. "My bedroom adjoins that of Cleon, and on two or three occasions it has happened that I have been summoned by him in the middle of the night to answer M. Platzoff's private bell which rings in his room. On answering this bell as Cleon's deputy, I have found that M. Platzoff, not being able to sleep, has summoned me to read to him, or to assist him on with his dressing-gown, and to light his pipe for him. "'But,' you will perhaps observe, 'what has all this rigmarole to do with the question of the Great Mogul Diamond?' "I reply that, in all probability, it has nothing whatever to do with it. But I think it requisite that you should know the details of my life at Bon Repos. Secondly, you must let me say what I have to say after my own fashion. And thirdly, the curious incident I have now to record would hardly be comprehensible to you without the preliminary details here given.