The dealer took another look at the tetradrachm through his magnifying glass, holding it by the edge with the careful touch of an expert. Then he shook his head slowly in a confession of ignorance. "Of course I could make a guess----" "No, don't," interrupted Mr Carlyle hastily. "An arrest hangs on it and nothing short of certainty is any good to me." "Is that so, Mr Carlyle?" said Mr Baxter, with increased interest. "Well, to be quite candid, the thing is out of my line. Now if it was a rare Saxon penny or a doubtful noble I'd stake my reputation on my opinion, but I do very little in the classical series." Mr Carlyle did not attempt to conceal his disappointment as he returned the coin to the bag and replaced the bag in the inner pocket. "I had been relying on you," he grumbled reproachfully. "Where on earth am I to go now?" "There is always the British Museum." "Ah, to be sure, thanks. But will anyone who can tell me be there now?" "Now? No fear!" replied Mr Baxter. "Go round in the morning----" "But I must know to-night," explained the visitor, reduced to despair again. "To-morrow will be too late for the purpose." Mr Baxter did not hold out much encouragement in the circumstances. "You can scarcely expect to find anyone at business now," he remarked. "I should have been gone these two hours myself only I happened to have an appointment with an American millionaire who fixed his own time." Something indistinguishable from a wink slid off Mr Baxter's right eye. "Offmunson he's called, and a bright young pedigree-hunter has traced his descent from Offa, King of Mercia. So he--quite naturally--wants a set of Offas as a sort of collateral proof." "Very interesting," murmured Mr Carlyle, fidgeting with his watch. "I should love an hour's chat with you about your millionaire customers--some other time. Just now--look here, Baxter, can't you give me a line of introduction to some dealer in this sort of thing who happens to live in town? You must know dozens of experts." "Why, bless my soul, Mr Carlyle, I don't know a man of them away from his business," said Mr Baxter, staring. "They may live in Park Lane or they may live in Petticoat Lane for all I know. Besides, there aren't so many experts as you seem to imagine. And the two best will very likely quarrel over it. You've had to do with 'expert witnesses,' I suppose?" "I don't want a witness; there will be no need to give evidence. All I want is an absolutely authoritative pronouncement that I can act on. Is there no one who can really say whether the thing is genuine or not?" Mr Baxter's meaning silence became cynical in its implication as he continued to look at his visitor across the counter. Then he relaxed. "Stay a bit; there is a man--an amateur--I remember hearing wonderful things about some time ago. They say he really does know." "There you are," exclaimed Mr Carlyle, much relieved. "There always is someone. Who is he?"