Geology 



is very difficult to obtain on these limestone wastes, 

 except during actual rain, as almost all the drainage 

 is underground. 



On visiting the dry waterfall of the night before 

 we found that a large stream was pouring over it and 

 falling into the crater below, which was half filled, but 

 was evidently not so full as it had been during the 

 night. No water was flowing down the valley below 

 the crater, and from this we judged that the outlet 

 must be subterranean, and that it was this water which 

 in its further course had disturbed us during the night. 



We determined to fully explore the lower part of 

 the cave as soon as the stream should be once more 

 dry and our apparatus have arrived from Lyell. 



In the meantime we continued our exploration of 

 the plateau. Making our way round the cliffs to the 

 head of the waterfall, we found a roaring torrent de- 

 scending a steep and somewhat narrow valley, and on 

 climbing to the summit of a low eminence, we saw 

 before us a level grass-covered plain with a small lake 

 or tarn in its centre, and behind this, and rising about 

 1000 feet above it, terraced mountains with flat tops. 



Flowing towards us from the foot of the lake was 

 a broad river shining in the sunlight ; at a point about 

 midway between our standpoint and the lake, the 

 river appeared to suddenly diminish to less than half 

 its volume and then to flow on to the head of the 

 waterfall which we had just left. 



Close to the point where the stream diminished, the 

 character of the scenery changed, and the grassy plane 

 gave place to the limestone clints on which we 

 stood. 



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