"'Der Herr hat recht!' muttered Rudolph, with a glance at me. 'Er versteht ja alles.' "'You know German?'--he says, 'What you don't know about diamonds isn't worth knowing,' I put in. Birchmore nodded with a half smile. "'I ought to know something about precious stones,' he said. 'I spent three years in a diamond mine, for one thing.' He seemed on the point of saying more, but checked himself, and went on scrutinising the stones, most of which were already in their new setting. 'A costly parure that,' he remarked at length. 'It wouldn't sell for a penny under thirty thousand pounds.' "'Five hundred eighty-five thousand francs, with the setting,' replied Rudolph, to whom the words had been addressed. 'Monsieur's estimate would have been correct, but that this stone here is a little off colour, and this one has a slight flaw, which is now in part concealed by the setting.' "'You travel under proper precautions, I trust?' said Birchmore, after a pause, turning gravely to me. 'I know the confidence you young fellows have in your courage and cleverness; but a dozen or a score of thieves might conspire together for such a prize as this, and against their skill and address no single man would stand a chance. Ah! I know something of it. I was robbed once.' "'Do tell me about it!' I exclaimed, with an impulsive betrayal of interest that made me smile the next moment. "'Another time,' said he, shaking his head; and presently he added: 'You will pardon me for presuming to counsel you?' "'My dear sir, I am much obliged to you. My idea is that the simplest precautions are the best. I shall carry the stones in an inner pocket, and I shall go armed. No one will suspect me; and if I am attacked, I shall make a good defence at all events.' "Mr. Birchmore said nothing more, and indeed seemed scarcely to listen to my remarks. I now suggested to him that he might show Rudolph his ring. He put his hand to his waistcoat pocket, and gave a half-suppressed ejaculation of disappointment and annoyance. He had left the ring at home! "'No matter; I will call to-morrow, Herr Rudolph,' he observed. 'I've no doubt I shall find what I want here, if anywhere. Good-morning--that is, if you are ready, Mr. Gainsborough. By the way, Rudolph, I suppose you put your treasures in a safe at night?' "'Oh, by all means, Herr,' replied the little Saxon. 'And I have a watchman also, who guards all night long.' "'A prudent fellow: yes, that will do,' murmured Mr. Birchmore, in an undertone to himself. Then, with a parting nod and smile, to which the jeweller did not respond, he sauntered out, I following him. We walked back to the hotel. I did not see him again until after dinner, when he offered me a cigar; and when we had smoked together awhile in silence, he said abruptly: "'I've found that stone.' "I looked at him inquiringly.