The afternoon was half gone, when, on one of these occasions, the scout who had just crept to the top of an elevation was seen by the others to gaze long and steadily in a particular direction through his field-glass. At length, apparently satisfied with what he saw, he stood up, and flashed a dazzling ray of sunlight from a small mirror that he held in his hand. Again and again did he send that flash over miles of prairie, before he saw the answering flash for which he was watching. Then he called the others up; they talked earnestly together for a few minutes, and, having reached some conclusion, they galloped rapidly away, almost at right angles to the course they had been following.