When at Youldeh the old fellow had mentioned this spot, Wynbring, as the farthest water he knew to the eastwards, and now that we had arrived at it, he declared that beyond it there was nothing; it was the ultima thule of all his geographical ideas; he had never seen, heard, or thought of anything beyond it. It was certainly a most agreeable little oasis, and an excellent spot for an explorer to come to in such a frightful region. Here were the three requisites that constitute an explorer's happiness--that is to say, wood, water, and grass, there being splendid green feed and herbage on the few thousand acres of open ground around the rock. The old black guide had certainly brought us to this romantic and secluded little spot, with, I suppose I may say, unerring precision, albeit he wound about so much on the road, and made the distance far greater than it should have been. I was, however, struck with admiration at his having done so at all, and how he or any other human being, not having the advantages of science at his command to teach him, by the use of the heavenly bodies, how to find the position of any locality, could possibly return to the places we had visited in such a wilderness, especially as it was done by the recollection of spots which, to a white man, have no special features and no guiding points, was really marvellous. We had travelled at least 120 miles eastward from Youldeh, and when there, this old fellow had told us that he had not visited any of the places he was going to take me to since his boyhood; this at the very least must have been forty years ago, for he was certainly fifty, if not seventy, years old. The knowledge possessed by these children of the desert is preserved owing to the fact that their imaginations are untrammelled, the denizens of the wilderness, having their mental faculties put to but few uses, and all are concentrated on the object of obtaining food for themselves and their offspring. Whatever ideas they possess, and they are by no means dull or backward in learning new ones, are ever keen and young, and Nature has endowed them with an undying mental youth, until their career on earth is ended. As says a poet, speaking of savages or men in a state of nature:-- "There the passions may revel unfettered, And the heart never speak but in truth; And the intellect, wholly unlettered, Be bright with the freedom of youth."