While he was riding along, with his gaze fastened thoughtfully on the ground, and wondering how many narrow escapes an African hunter could have before some wild beast succeeded in getting the better of him, his eye chanced to fall upon something that instantly arrested his attention.
In Eaton he had probably walked over such objects a dozen times in a day, and never noticed them at all; but they were so uncommon in the wilds of Africa that the sight of this one interested him at once—so much so that he swung himself from his horse and picked it up.
It proved to be a piece of brown envelope. Inside of it was a strip of white paper, at which he gazed in the greatest amazement. It was part of the map that his friend Mr. Lawrence had drawn for him. Scarcely able to credit the evidence of his eyes, Oscar put the paper into his pocket and climbed back into his saddle.
"How, in the name of all that's mysterious and bewildering, did that map get scattered about in this way?" he kept saying to himself, and every time he asked the question he took the paper out of his pocket and looked at it again. "It certainly is my map—or all there is left of it. I would know it if I had picked it up in the streets of London; but if I had found it there I could not be more surprised than I am to find it here. I am sure that I put it in the third pocket on the right-hand side of the tent, and how in the world—— I wonder if McCann——"
Oscar took off his hat and dug his fingers into his head to stir up his ideas. That name suggested something to him, and brought back to his memory a good many little incidents that had happened since he left Zurnst—all trivial enough in themselves, but which when taken together made up a weight of evidence against the after-rider (an after-rider only in name) that was overwhelming.
"I ought to have been on the lookout for some such thing as this," thought Oscar, who, beyond a doubt, would have come to an open rupture with McCann if the latter had been near him at that moment. "He has done everything he could to discourage me. He has put the brakes on the wagon when we were going up hill in order to make the oxen part the trek-tow; he has tried to lead me out of my course, and make me lose my way on the plain, so that he could turn me back to Zurnst; he has told the most dreadful stories of the dangers I was running into, and tried over and over again to make me promise that I would secure what specimens I could here, and then go back; and, as a last resort, he has destroyed my map. It must have been McCann, for there is no one else about the wagon who knows the value of that piece of paper."
Oscar felt savage enough during the rest of the ride, and consequently he was just in the right humor to act—and to act resolutely—in an emergency that presently arose.
While he was thinking about McCann, and wondering if there were any way in which he could satisfy himself of the man's guilt before he openly charged him with destroying the map, an exclamation from his after-rider aroused him.
He looked up and found that he was in plain view of the fountain. The oxen were gathered on the bank, and on the opposite side of them were the driver and fore-loper, who were shouting and cracking their whips to turn the cattle away from the fountain.