"Now we come to this--our second visit to the house in Maida Vale. To be exact, it was between eleven and twelve on the second night after the disappearance of the diamond. As on the previous night, we gained access to the garden by the door at the back--that, on each occasion, was unfastened, while the gate giving access to the road in Maida Vale was securely locked. And, as on the previous night, we quickly found that up to then at any rate, the house was empty. But not so the garden! While I was looking round the further side of the house, Purvis took a careful look round the garden. And presently he came to me and drew away to the asphalted path which runs from the front gate to the front door. The moon had risen above the houses and trees--and in its light he pointed to bloodstains. It did not take a second look, gentlemen, to see that they were recent--in fact, fresh. Somebody had been murdered in that garden not many minutes--literally, minutes!--before our arrival. And within two minutes more we found the murdered man lying behind some shrubbery on the left of the path. I knew him for the younger of the two Chinese--the man called Chen Li. "This discovery, of course, made us aware that we were now face to face with a new development. We were not long in arriving at a conclusion about that. Chang Li had found out that his friend had become possessed of these valuable--he might have discovered the matter of the diamond, or of the bank-notes or both--how was immaterial. But we were convinced, putting everything together, that he had made this discovery, had probably laid in wait for Chen Li as he returned home that night, had run a knife into him as he went up the garden, had dragged the body into the shrubbery, possessed himself of the loot, and made off. And now we were face to face with what was going, as we knew, to be the stiffest part of our work--the finding of Chang Li. We set to work on that without a moment's delay. "I have told you that Purvis and I have a pretty accurate knowledge of Chinamen; we have both had deep and intimate experience of them and their ways. I, personally, know a good deal of the Chinese Colony in London: I have done business with Chinamen, both in London and South Africa, for years. I had a good idea of what Chang Li's procedure would be. He would hide--if need be, for months, until the first heat of the hue and cry which he knew would be sure to be raised, would have cooled down. There are several underground warrens--so to speak--in the East End, in which he could go to earth, comfortably and safely, until there was a chance of slipping out of the country unobserved. I know already of some of them. I would get to know of others.