The Onetapu Desert, or "desert of sacred sand," as its name implies, forms one of the most curious features of this region. It stretches from the eastern slope of Ruapehu to the banks of the Waikato River, across the centre of the great table-land, and covers an area of over fifty square miles. In summer it is parched and dried, and in the winter months when the snows cover it, it is both dangerous and difficult to traverse. As we neared this trackless waste, the rich vegetation of the plains gradually died away, and gave place to the stunted plants and shrubs which we had always found growing on the lower scoria deposits. This vegetation did not cover the ground in every direction, but grew in patches here and there, and often in a very attractive way. The desert, at the surface, is composed entirely of a deposit of scoria, with rounded stones and trachytic boulders above, while, in some places, rise enormous lava ridges. Here and there a trickling watercourse winds over it, but taken altogether it is a dreary, monotonous expanse, which the superstitious minds of the natives have peopled with _taniwhas_ and evil spirits. By its formation, it would appear as if Ruapehu, when in a state of activity, had distributed its showers of ashes and lava over this wide region, and it would also appear that, at the period at which this extensive deposition of scoria occurred, there must have been growing upon this very spot an extensive forest similar to that now to be found on the western side of the mountain, for, as we rode over the dreary expanse, we found the remains of enormous trees which had been converted into charcoal, as it were, at the time when the fiery ashes swept over them, and which had since become exposed, as the upper surface was denuded by the action of the water flowing down from the mountain. Towards sundown we gained the upper waters of the Waikato, which here wound across the desert in the form of a small stream coming from the direction of Ruapehu. After crossing this we struck up towards the Kaimanawa Mountains, to the Mamanui stream, where there was a deserted Maori camping-place, and where we found excellent feed for our horses. The spot where we pitched our camp stood at an elevation of 3727 feet above the sea, on the banks of the Mamanui, which wound from the mountains to form one of the many tributaries of the Waikato which have their rise in these extensive ranges. The moon shone brightly by the time we had pitched our tent, and the tall heights, towering around us with their splendid vegetation, sheltered us from the chilly blasts that swept across the plains, and, taken altogether, it was a comfortable and pleasant spot in comparison to the weird mountains upon which we had been recently camped.