From the aspect of the place, and the still warm embers of fires, John guessed that the camp had been broken up rather later in the morning than usual, and not very long before his arrival. This conclusion led him to press on with redoubled vigour, and at the same time with caution. Royce asked himself more than once what he would do when he came up with the raiders. Always he had to admit that he did not know. It was hopeless to attempt to form a plan. Indeed, he acknowledged to himself that the whole enterprise was pretty hopeless. The hoof marks and the prints of feet were so numerous that the party must be a large one. The Hausa had spoken of thousands of Tubus. That was no doubt an exaggeration; the negro is always ready to magnify numbers; but it was almost certain that the horsemen mustered a score or two. What was more surprising was the character of the footprints. Royce's full party consisted of only sixteen carriers, of whom two were now with him; but the depth of the impressions on the sandy soil, rather than their number, indicated that there were many more than fourteen prisoners. African natives march nearly always in single file, each man stepping in the tracks of the man in front of him; the footprints now before him were so deeply impressed that they must have been made by a large number of men. Of the three trackers, John went first, as the most experienced in travelling over this kind of country. Every now and again he would point to the marks of Challis's boots, when they were clearly distinguishable from the other prints. Presently he declared that Massa Chally must be tied to a horse, for his footprints corresponded regularly with the marks of four hoofs. Towards midday the track struck into a well-beaten native path, on which the foot-prints were less clearly marked. It ran northward over undulating wooded country, broken now and then by open spaces of prairie-like land. John declared that there were signs of their approaching a river. When they came to the open spaces, he slackened pace, and scouted forward with great caution, to make sure of not stumbling upon the rear of the enemy. It was very unlikely that these had any idea of being pursued, but they were in hostile country, the people in the far-distant villages were their bitter foes, and they would hardly neglect the usual precautions against surprise or sudden attack. From one of these spaces, to which John had gone on ahead, he ran back by-and-by, his eyes lit with excitement. "See horses, sah!" he cried. "Going from us?" asked Royce anxiously. "Tails dis way, sah." "Lead on slowly. Be sure to keep out of sight." Since the horses were moving, clearly the only thing to be done was to keep in touch with them for the present, and seek a favourable opportunity of ascertaining the exact strength of the party and their order of march.