The whole of this side of Ruapehu appeared singularly rugged, and above the deep gorges the enormous bluffs and precipices seemed to mount one above the other to the glacier-crowned peaks above. We struck into a boulder-strewn ravine, and, after following this along for a considerable distance, we found that it brought us to the dark mass of rocks which the natives had indicated to us. It was, however, clear at once that the true source of the river was a long distance up the mountain from this point. The dark rocks, which were nothing more than enormous outcrops of lava, formed the portals, or entrance, as it were, to a still deeper gorge, which led further into the mountain, and which looked as weird and as dismal as anything Dante or Doré had ever created. When we had got fairly into this tremendous chasm, a most curious sight presented itself. Below our feet was the bed of the ravine, strewn with boulders of all sizes, which lay scattered about in endless confusion, as if hurled from the heights above by the hands of mountain giants. On our left rose an immense lava wall, over 100 feet in height, and on our right, rising from the bed of the ravine, was a wide stratum of alluvial drift, composed of sand and water-worn boulders. Resting on this stratum, just as it had cooled, was a lava stream, about 200 feet in perpendicular height, as sharp and as clear in all its proportions as if it had been cast out but yesterday from the fiery craters of the mountain. Dark, bright, and shining with a metallic lustre, it looked like a solid wall of bronze built by Cyclopean hands, the stupendous jagged ridge which crowned it resembling the rampart of an embattled fortress. This appeared to be one of the grandest specimens of a trachytic lava bed to be found in any part of the world, and it formed one of the most interesting geological phenomena I had ever beheld. Looking at this stupendous mass, one could fairly realize how widespread and how tremendous in its proportions must have been the volcanic action of Ruapehu. The stream of lava which had formed this great deposit had evidently come from one of the many central craters of the mountain, and had rolled down in a molten stream for a distance of several miles, until it had gradually cooled into its present form. When gazing up at this singular monument, it could be seen that there was not a single flaw in its whole surface to mar the general outline of its colossal proportions. Here and there from the hard metallic surface, which shone like bronze by some powerful agency difficult to comprehend, blocks of the adamantine rock had fallen into the ravine below, but even every line of their surface was as sharp and as angular as if they had been just wrought into form under our eyes. [Illustration: GREAT TRACHYTIC LAVA BED.]