"I call that a stroke of genius," he said to himself. "The question is, will the sound scare Goruba away? He is bound to hear it, though it is not so loud as I expected. But, after all, there is nothing to make him connect the sound with his own movements, so I fancy there will be a little surprise in store for him." At dusk that evening he sat in his room, watching the pile of tins, and waiting eagerly for the alarm signal. But it did not come. All night he remained awake, unable to sleep from excitement. Not a sound broke the stillness. Next evening he took up his post at the same time. Tired and sleepy, he was just falling into a doze when the tins fell with a crash that made him jump. Pulling off his boots, he slipped very quietly into the well-yard and stooped below the top of the wall. He knew that he was in plenty of time, for the intruder was sure to move slowly and with caution. With his electric torch in his left hand and his revolver in his right, he passed round to the side of the well opposite to where the staples were placed. In a few seconds he heard a slight rustle; the man was climbing over the coping of the well. He saw his form, a huge black shape against the dark blue sky. The man stood listening for a moment, then crept towards the doorway leading to Royce's quarters. Royce stole on tiptoe after him, and just as he reached the opening pressed the button of the torch. The negro turned instantly, and the bright ray from the torch flashed upon the startled eyes of Goruba. Royce had expected astonishment, even dismay. He was not prepared for the extraordinary readiness, decision, presence of mind with which the negro would act. Without an instant's hesitation, Goruba sprang at him with uplifted knife. Royce fired, but either he missed or there was no stopping power in the bullet, for in another fraction of a second he was hurled back towards the well, narrowly escaping toppling over the coping into its depths. But if Royce missed, so did Goruba, dazzled, perhaps, by the light of his torch. His knife crashed on the coping, and was shivered to pieces. Next moment Royce found himself for the second time locked in the giant's embrace. Exerting all his strength, he strove to prevent the negro from hurling him into the well. He shouted. Answering shouts came from the men. And then he discovered, to his surprise, that Goruba was not so formidable an antagonist as when they had first met. His grip was not so firm; all the pressure came from his left arm. Encouraged by this, Royce grappled him closely, tried a back-throw he had learnt in jiu-jitsu, and had Goruba on his back as the Hausas, headed by Kulana, came shouting into the yard. Royce was only just in time to prevent them from plunging their knives into the struggling negro. At his order, they tied him up with cords, so tightly that he howled with pain. "Loosen them!" cried Royce. "Don't hurt him." Kulana stared.