CussEN. — On the Waikato Biver Basins. 409 



now dry. They are bordered with high water-worn cHffs of 

 tufa, showing that they were once the beds of powerful 

 streams. Two of the principal streams of the Patetere flow 

 into the Waikato; the others, following the natural slope of the 

 valley, find their way to the Hauraki Gulf. 



The next remarkable change in the course of the Waikato, 

 and that which was attended by the most serious results in the 

 great middle basin, is that which took place at Piarere, about 

 fom-teen miles above Cambridge. Any one travelling the road 

 from Cambridge to Oxford could scarcely fail to remark the 

 well-defined broad valley, bordered by steep clifis, which runs 

 in a north-east direction by Hinuera towards Matamata. 

 There is little doubt that the Waikato River once flowed down 

 this naturally-sloping valley, and thence to the sea at the 

 Hauraki Gulf. But from some cause it again left its old bed, 

 and, turning to the westward, passed through the gorge between 

 Maungatautari and Hinuera Ranges for six miles, and de- 

 bouched into the great middle basin at Cambridge. Here, 

 again, we have the same sequence of events recorded that took 

 place at Whakamaru — the river formed a sinuous lake in the 

 valleys above, extending backwards for a distance of eight 

 miles, and covering the Waipa Plains, which were evidently 

 the bed of a lake. We find the remains of a deep alluvial 

 deposit, chiefly of light pumice-sands, which filled the valleys 

 running in between the spurs in level plains. Through these, 

 again, the streams in wearing out their deep channels exposed 

 the strata of river-gravel, pumice-sand, and detritus, including 

 large trunks of trees. This deposit fills the valley at Paeroa, 

 where the Auckland Agricultural Company's homestead at 

 Cranston is situated : it runs into the valleys between the 

 ridges, varying in depth from 120ft. downwards. Following 

 down the old river-bed towards Matamata, the deposit thins 

 out like a wedge, and finally almost disappears four or five 

 miles from the present river-bed. 



The river, in working its channel deeper through the 

 barriers in the Maungatautari Gorge, gradually drained off the 

 waters of the lake, leaving behind, in the valley above, eight 

 rows of terraces, which fringe the river on either side, indi- 

 cating each a different stage in the lowering of the bed. 



The height of the land through the gorge which the river 

 now traversed was certainly over 200ft. above the present 

 river-bed, and through this to the bed-rock the river has eroded 

 its channel. We have now arrived at an area in the Waikato's 

 basins where the facts to be recorded are of a perplexing and 

 recondite character. The broad plain in central Waikato 

 known as the "Waikato middle basin" has an area of five 

 hundred square miles. We find an alluvial deposit all over the 

 lower areas of this valley : in places it is 150ft. in depth. The 



