Yet they had to labour as navvies all day long under the broiling rays until sundown, with hardly any intermission except the short time allowed for their midday meal. The overseers rode about abusing them in German and Low Dutch, and plying their cowhide whips over the backs of those who fainted or shirked their work. It was worse than slavery, as these Boers did not care whether the prisoners lived or died. If they resented the savage stroke by so much as a look, they were tied up and flogged almost to death. If they showed fight, they were at once shot down and flung to one side like carrion. Our heroes could not have endured the whip even with their hopes of liberty buoying them up, therefore they laboured with a will, and gave the brutes no chance of chastising them. Sometimes the whip cracked over their heads, but fortunately for their future, it did not descend on their backs. The reason for this was that their friends outside had managed to get at these venal wretches, and paid them a weekly sum to spare the young men that last outrage. They were all the more closely watched for this very reason so that they might not escape. During the day this would have been impossible, as before they could have run a dozen steps, they would have been shot down. They had passed a fortnight of this wretched existence, when, one day, as Ned looked up, he saw a party of horsemen riding past. Amongst them was Philip Martin, who, catching his eye, pointed quickly north, and then patted his horse. Ned knew what that meant. They were to run northward when their chance came, where friends and horses would be in readiness. His heart bounded as he read the signals and saw his friend gallop past him. Then he bent and plied his pickaxe with renewed energy. In spite of their semi-starvation, the hard labour did not hurt our heroes. Already they had got over the utter exhaustion that made them so helpless when they reached their cells. They had lost flesh woefully, but their muscles were becoming tough and hard as steel, and their skins tanned and sun-proof. They did not fear but that they would be able to run once they got the chance. Their cell was a small one, with corrugated iron on two sides and mud-cemented walls on the other two. Each night they were carefully searched before being locked in, so that it was impossible for them to smuggle in any tool. Still, now that Ned had seen help so close at hand, he did not despair. What he could not get in himself might be sent to him from the outside. That night he told his chums what he had seen, and their spirits rose wonderfully at the news. "They will be on the outlook, I am sure, therefore we must let them know whereabouts we are located." After some consultation the idea struck them to hang out a bit of rag from one of the narrow air-holes. If they did this that night, it was almost sure to be noticed and understood by those on the watch outside.