The name of the visitor I expected, and who hopped up the stairs which led to my chambers half an hour after I entered them, was Bob Tucker. He is a friend of mine, with plenty of money at command, and has no need to work for a living; but he has a fad, if I may so express it. This fad lay in the detective line, and to give him a job in that direction was to bestow a favor upon him. He entered upon it _con amore_, and pursued it with a zest never to be found in the professional, who works by the job, or the hour, or the day. He has often said to me that if he were to lose his money he would start an office of his own and lead a jolly life. Whether that meant a jolly life to others is a doubtful point. Anyway, he is an enthusiastic young fellow of about six and twenty, and is never so happy as when he can adopt a disguise and hunt something or somebody down. He objects to be called Robert, which he insists is not his proper name. He distinctly remembers, he avers, being christened Bob, so Bob Tucker he is to all his friends. So far as I am personally concerned, this is convenient to me, my name being Robert, which I prefer to Bob. I had foreseen the likelihood of the failure of the search upon which I had entered with Emilia, and the surer arrow in my quiver to which I referred when I spoke to Emilia about returning to London was Dr. Peterssen. It was my intention, if all else failed, to break a lance with him, directly or indirectly, and with this object in view I had instructed Bob Tucker to find out where he lived, what kind of establishment he kept, what his neighbors thought of him, the character he bore, and, in short, anything and everything about his establishment which could possibly be learned. Bob was delighted with the task, and undertook it eagerly. "Does he live in London?" he asked. "Don't know," I answered. This increased Bob's delight, and he said he would show me something when he made report to me. Of course I told him all I knew of the man, and that he had charge of at least one patient who was not in his right mind. "Well, Bob?" I said, on this evening. "Give me a drink first," was Bob's rejoinder. I gave him one, and took one myself. We clinked our glasses and emptied them. Then Bob lit a cigar, and so did I. "Ready?" said he. "Quite ready," said I. "Keeps a private madhouse," said Bob. "Queen Anne's dead," said I. "Has more than one patient." "Has three. A man, or gentleman, and two children." "Children?" "Children. Prefers them. Less trouble. Besides, longer expectations with young 'uns. More time for them to grow old." "True," said I. It will be observed that it was a speciality of Bob's to speak in short sentences. "Man, or gentleman," continued Bob, "harmless. Gentle as a dove. Greengrocer's boy told me. Sees him sometimes. In the grounds. Pities him." "How old is this poor gentleman, Bob?"