Guy and Poeskop cantered quietly in the direction of the blue wildebeest, a troop of some eighty of which were grazing quietly about a mile and a half away. They approached without difficulty to within some six hundred yards, and then, from the left of them, came the report of a rifle, then another, and yet another. Already, then, Mr. Blakeney and Tom were engaged! Guy looked in that direction, but could see no more than the distant figures of his uncle and cousin scouring away after some specks--the game they were pursuing--in front of them. He now turned his attention to the wildebeest of which he was in pursuit. The noise of the shooting had already disturbed them. Their heads were up, scenting the air for danger, and those animals which had been lying down had sprung to their feet. There was no time to be lost. "We must _hart-loup_ [gallop]," said Poeskop quietly; and shaking up the willing nags, the two dashed headlong for the game. Now, at last, the wildebeest took real alarm. Bunching together in a big phalanx, plunging and capering, and whisking their long black tails, the troop set off at what looked like a heavy lumbering gallop, but was in reality a swift pace, taking a course right-handed in the direction of the river-bed. Guy, as he galloped, watched the herd with intense interest. It was the first time he had run blue wildebeest, or, as he had been accustomed to call them in England, brindled gnu. Their big, heavy, somewhat buffalo-like heads, carried low as they ran, and the masses of dark hair that covered their necks, throats, and faces, gave them a cumbrous appearance; but there was no mistake about the pace they went. They swept over the grass plain as fast as the ponies could gallop, and they were evidently not yet stretching themselves out. It was going to be a long and a stern chase. Pursued and pursuers had run somewhat over a mile, still bending towards the river, with its thick fringe of bush and low timber; five hundred yards separated Guy from the nearest wildebeest. They were stringing out now; it was useless to think of firing just yet; and then a diversion happened.