"Thank you very much, Mr. Ferguson," said Gilbert, gratefully; "but I don't think I shall need it. I shall have money enough, but that is not all. From what you say, I am afraid, if I went to St. Louis, it would only be a wild-goose chase." "Stay," said Mr. Ferguson, after a moment's thought; "an idea strikes me. You may gain the knowledge you want with very little trouble. Mind, I say _may_. It is not certain." "How, sir?" said Gilbert, eagerly. CHAPTER XXV. MAURICE BETRAYS HIMSELF. "In this way," answered Mr. Ferguson. "Your uncle did not register his name at the Burnet House till after his encounter with you in the street. Probably his reason for changing his hotel was to prevent your examining the register of the one at which he was previously staying, and so ascertaining his real residence. The same motive would lead him to give the wrong address in the new hotel." "Yes, sir; that seems likely, but how is that going to help me?" "You must try to ascertain where he formerly stopped. Go to the principal hotels, and examine their registers for a fortnight back. Probably that will cover all the time in which your uncle is likely to have arrived." "Yes, I see," said Gilbert, brightening up. "It is a good plan, and I think it will succeed." "I hope so, for your sake." Gilbert lost no time in following out his employer's suggestion. First, he went to the Gibson House; but he examined the books to no purpose. He looked back as far as twenty days, but could not find the name of James Grey. "He can't have stopped at this hotel," he said to himself. Next he went to the Spencer House. It occurred to him that possibly his uncle's name might be recognized, so he asked the clerk: "Has a gentleman named James Grey stopped with you lately?" "Grey? I believe so," said the clerk, after a moment's reflection. "He left us about a week since." "Yes, it is the same," said Gilbert, eagerly. "Was he here long?" "Only two or three days." This, of course, made the examination easy. In point of fact, ten days back Gilbert found recorded on the books: James Grey, Clayton, Illinois. "Clayton, Illinois," repeated Gilbert; "that's a place I never heard of. I wonder where it is? It can't be much of a place. Can you tell me in what part of Illinois Clayton is?" he inquired of the clerk. "Never heard of it," said that official, indifferently. "Clayton, Illinois?" said a gentleman who had just come up to leave his key. "I can tell you where it is." "Where, sir?" "It is a small town on the Mississippi river, north of Alton--I should think about thirty or forty miles. I never was there, but I've passed it while ascending the river on a steamboat." "Thank you, sir," said our hero.