"Oh, no," said the doctor. "Cement in some form or another is very ancient;" and he paused for a few minutes while the last baskets of rubbish which had been thrown out were carefully examined. "Nothing here," said the doctor. "Now, Denham, I want that iron bar that you use to make the holes for the tent pegs." "Hop pitcher? Here, Bob, mate, run to the waggon and fetch it." The interval of time taken by the younger keeper to fetch the big pointed crowbar was utilised for further search, during which the two blacks came back and stood a little aloof, watching curiously the acts of their white companions. "That's right, mate," replied Denham.--"Oh, well, if you like; jump down, then. The boss wants a hole picked, I suppose, for you to break up a bit of the floor here to see what it's like." The keeper was handy enough with the fresh tool, and after picking out a good many small pieces of what proved to be powdered granite, consolidated probably by lime, or perhaps only by time itself, he called for one of the stones that had been thrown out, laid it by the side of the hole he had picked, and then thrusting down the iron bar and using the stone as a fulcrum, he levered out a good-sized piece of the hard cement. "Throw it up here," cried the doctor, who caught it deftly and held it in the sunshine, examining it carefully. "No," he said, in rather a disappointed tone. "Here's a bigger bit here, sir," said Bob, "as seems loose. Yes, out you come!" And pressing his lever down hard, he brought up a great flake of the flooring, nearly a foot long and some inches wide. This he handed to Buck, who examined it casually as he bore it to the side of the hole and handed it to the doctor. "It's broken up granite, sir, for certain," he said, "and this other side sparkles just like--" He was going to say something, but the doctor excitedly, so to speak, snatched the word from his lips. "Yes," he cried--"gold!" The two boys started forward excitedly. CHAPTER THIRTY ONE. AN EXPLOSION. "Yes," said the doctor, as he scanned some little specks of the pale yellow glistening metal, and the two blacks crept silently closer, "this is gold, sure enough." "I don't know much about these things," said Sir James, examining the big flake carefully, "but I didn't think that it was possible to find gold in cement. If it had been quartz rock, doctor--" "Ah, you are thinking of gold ore, Sir James," said the doctor, taking out his knife and opening it. "These are scraps of manufactured gold." "Why, who could have manufactured them," said Mark sharply.