Mr. Ruby found the Duchess, on that occasion, difficult to please. She wanted something in diamonds, to present to Lady Edith Linglithgow on the occasion of her approaching marriage. As Lady Edith is the Duke's first cousin, as all the world knows, almost, as it were, his sister, the Duchess wanted something very good indeed. Nothing which Messrs. Ruby and Golden had seemed to be quite good enough, except one or two things which were, perhaps, too good. The Duchess promised to return with the Duke himself to-morrow, or, perhaps, the day after. With that promise Mr. Ruby was forced to be content. The instant the difficult very great lady had vanished, Mr. Golden came into the room. He placed upon the table some leather cases. "Ruby what do you think of those?" "Why, they're from stock, aren't they?" Mr. Ruby took up some of the cases which Mr. Golden had put down. There was quite a heap of them. They contained rings, bracelets, necklaces, odds and ends in diamond work. "Anything the matter with them, Golden?" "There's this the matter with them--that they're all paste." "Golden!" "I've been glancing through the stock. I haven't got far, but I've come upon those already. Somebody appears to be having a little joke at our expense. It strikes me, Ruby, that we're about to be the victims of one of the greatest jewel robberies upon record." "Golden!" "Have you been showing this to the Duchess?" Mr. Golden picked up a necklace of diamonds from a case which lay open on the table, whose charms Mr. Ruby had been recently exhibiting to that difficult great lady. "Ruby!--Good Heavens!" "Wha-what's the matter?" "They're paste!" Mr. Golden was staring at the necklace as though it were some hideous thing. "Paste!--G-G-Golden!" Mr. Ruby positively trembled. "That's Kesteeven's necklace which he brought in this morning to see if we could find a customer for it." "I'm quite aware that this was Kesteeven's necklace. Now it would be dear at a ten-pound note." "A ten-pound note! He wants ten thousand guineas! It's not more than an hour since he brought it--no one can have touched it." "Ruby, don't talk nonsense! I saw Kesteeven's necklace when he brought it, I see this thing now. This is not Kesteeven's necklace--it has been changed!" "Golden!" "To whom have you shown this necklace?" "To the Duchess of Datchet." "To whom else?" "To no one." "Who has been in this room?" "You know who has been in the room as well as I do." "Then--she did it." "She?--Who?" "The Duchess!" "Golden! you are mad!" "I shall be mad pretty soon. We shall be ruined! I've not the slightest doubt but that you've been selling people paste for diamonds for goodness knows how long." "Golden!" "You'll have to come with me to Datchet House. I'll see the Duke--I'll have it out with him at once." Mr. Golden threw open the door. "Thompson, Mr. Ruby and I are going out. See that nobody comes near this room until we return."