“As it is assumed that Marks had a lot of money on him at the time, we may, I think, dismiss the blacks as the actual murderers. They would have little use for banknotes and no use for negotiable securities. This, of course, Mr Dancing Billy Wagtail, is all conjecture. Somewhere about here Marks was killed. The odds are that he was not killed without a struggle, and wherever that struggle took place, there the ground will have received some evidence of it. By this time the sand will doubtless have buried it, but all the same it will be there-a spot or two of blood, a coin, even a hair or wisp of cloth, or a dozen other things that can be detached from human beings through carelessness or violence.

“I must proceed along two distinct lines. First, to find out what has become of Marks’s body, and second, to find what living person benefited by Marks’s death. We must go into the history of Marks. Mr ChiefCommissioner, that is your job. Anyway, Marks was one of your satellites. In the meantime I must study the Windee people, both black and white-especially black; because the black who put up the sign can tell me what happened here. Now, what…”

Bony’s attention was drawn to the ants’ nest at his side. From the corner of his eye he had seen a sparkle of blue light, but when he looked directly at the nest it had vanished. The large circular hole within the rampart was alive with the black ants. Watching them, he observed that they were bringing up out of the nest small stones about half the size of a field pea. These they deposited on the inside slope of the rampart. The man observed that each ant laid down its tiny load on the west side of the hole, where the surrounding rampart cast a shade, thence to hurry round to the east side, which was in full sunlight, and from there pick up another small stone and with it hurry below.