Further Exploration of Centre Valley 



side of the valley, and by this lowest part the waters 

 impounded between the ice-front and the ridge of 

 morainic debris had overflowed, and after cutting 

 through the thin layer of loose material had continued 

 the excavation of its channel in the solid rock below on 

 the same line. In the lake were several rows of small 

 islands, evidently the highest parts of smaller moraines 

 now almost submerged beneath the waters. 



At the upper end of the lake was an extensive delta, 

 formed by the waters of the inflowing river, which had 

 extended for nearly two miles from the original mouth 

 of the stream. Little material was now being added to 

 the delta, as the waters of the stream appeared clear and 

 free from sediment. Round the shores of the lake was 

 a deposit of gravel, resembling to some extent a shingle 

 beach, but consisting of smaller pebbles. This was 

 several feet above the present water-level, a fact that 

 was doubtless due partly to the higher level of the water 

 during winter and early spring, when the floods come 

 down from the melting snows on the higher ground. 



Above the upper end of the lake we encountered 

 another dyke of quartz-porphyry, with large pink 

 felspars, similar to the one near the mouth of Tin Creek, 

 and immediately above this a small tributary stream 

 flowed in from the north, and as the gravel in its bed 

 consisted of large and angular pieces of granite, we 

 concluded that the main mass of that rock was not very 

 far away. 



We stuck to the main stream and pushed forward as 

 quickly as our impedimenta would allow. Of this we 

 had a considerable amount, as, in addition to camp outfit, 

 we had also a supply of ice-axes and ropes, which would 



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