"Eh? What?--_Nom de chien!_ No!" He struck his knee with his hand. "Fool! Why did I not think of that? But still"--he grew more thoughtful--"I should have to show it to get it cut, and I did not know where to go. And the value would have been less." "Just so--but it's the regular thing to do, I may tell you, in cases like this. But go on. About Hatton Garden, you know." "I thought that I must make myself known among the merchants of diamonds, and then, perhaps, I should learn the ways, and one day be able to sell. As it was, I knew nothing--nothing at all. I waited, and I saved money in the café. Then, when I could do it, I dressed well and went and bought some diamonds of a dealer--very little diamonds, a little trayful for twenty pounds, and I try to sell them again. But I have paid too much--I can only sell for fifteen pounds. Then I buy more, and sell them for what I give. Then I take an office in Hatton Garden--that is, I share a room with a dealer, and there is a partition between our desks. My wife attends the café, I go to Hatton Garden to buy and sell. It loses me money, but I must lose till I can sell the great diamond. I get to know the dealers more and more, and then to-night, as I go home----" he finished with an expressive shrug and a wave of the hand. "Yes, yes, I think I see," Dorrington said. "As to the diamond again. It doesn't happen to be a _blue_ diamond, does it?" "No--pure white; perfect." Dorrington had asked because two especially famous diamonds disappeared from among the French Crown jewels at the time of the great Revolution. One blue, the greatest coloured diamond ever known, and the other the "Mirror of Portugal." Bouvier's reply made it plain that it was certainly not the first which he had just lost. "Come," Dorrington said, "I will call and inspect the scene of your disaster. I haven't dined yet, and it must be well past nine o'clock now." They returned to Beck Street. There were gates at the dark entry by the side of the Café des Bons Camarades, but they were never shut, Bouvier explained. Dorrington had them shut now, however, and a lantern was produced. The paving was of rough cobble stones, deep in mud. "Do many people come down here in the course of an evening?" Dorrington asked. "Never anybody but myself." "Very well. Stand away at your side door." [Illustration: "DORRINGTON, WITH THE LANTERN, EXPLORED THE MUDDY COBBLE STONES."]