Nothing out of the ordinary may go unchallenged or uninvestigated by the wild beast which would survive; and so Tarzan took to the trees and doubled back upon his trail, directed by a natural assumption that if he were being stalked the stalker had been following behind him.

As he swung down wind through the trees, following the middle terrace where the lower branches would better conceal him from the eyes of the enemy on the ground, he realized that the direction of the wind would carry the scent spoor of him he sought away from him and that he must depend wholly upon his ears for the first information of the presence of a foe. He commenced to feel a little foolish as the ordinary noises of the jungle were unbroken by any that might suggest a menace to him. He commenced to compare himself with Wappi the antelope, which is suspicious and fearful of everything. And at last he was upon the point of turning back when his keen ears detected a sound that was not of the primitive jungle. It was the clink of metal upon metal, and it came faintly from afar.

Now there was a point to his progress and a destination, and he moved more swiftly but none the less silently in the direction from which the sound had come. The sound that he had heard connoted men, for the wild denizens of the jungle do not clink metal against metal. Presently he heard other sounds, the muffled tramp of booted feet, a cough, and then, very faintly, voices.

Now he swung to the left and made a wide detour that he might circle his quarry and come upon it from behind and upwind, that thus he might determine its strength and composition before risking being seen himself. He skirted a clearing which lay beside a river and presently reached a position to which Usha the wind bore the scent spoor of a party of blacks and whites. Tarzan judged there to be some twenty or thirty men, with not more than two or three whites among them.

When he came within sight of them, they had already reached the clearing beside the river and were preparing to make camp. There were two white men and a score or more of blacks. It might have been a harmless hunting party, but Tarzan's premonition kept him aloof. Concealed by the foliage of a tree, he watched. Later, when it was dark, he would come closer and listen, for he might not wholly ignore the warning his strange sense had given him.

Presently another noise came to his ears, came from up the river-the splash of paddles in the water. Tarzan settled down to wait. Perhaps friendly natives were coming, perhaps hostile; for there were still savage tribes in this part of the forest.

The men below him gave no signs that they were aware of the approach of the canoes, the noise of which was all too plain to the ape-man. Even when four canoes came into sight on the river, the men in the camp failed to discover them. Tarzan wondered how such stupid creatures managed to survive. He never expected anything better from white men, but he felt that the natives should long since have been aware of the approach of the strangers.

Tarzan saw that there were two white men in the leading canoe, and even at a distance he sensed something familiar in one of them. Now one of the blacks in the camp discovered the newcomers and shouted a warning to attract his fellows. At the same time the occupants of the leading canoe saw the party on the shore and, changing their direction, led the others towards the camp. The two white men, accompanied by some askaris, went down to meet them; and presently, after a conversation which Tarzan could not overhear, the four canoes were dragged up on the bank and the newcomers prepared to make camp beside the other party.

Chapter TWO..The Terra Safaris

AS THE TWO WHITE MEN stepped from their canoe, Pelham Dutton was not greatly impressed by their appearance. They were hard and sinister looking, but he greeted them cordially.