1876.] . Lake Wakatipu, New Zealand. 387 
As the evidence of a synclinal axis is nowhere apparent in the 
valley of Lake Wakatipu, we are unable to account for its exist- 
ence by the upheaval of the mountains on either side of it. We 
are likewise at a loss to find any indication of the rocks having 
been rent asunder by volcanic forces. The formation of the val- 
ley can be referred only to the third cause, that of denudation, 
or the slow removal by ice and water of the rock that once filled 
it to a height greater than that of the mountains which now 
tower above it. 
It may seem strange at first sight that such an immense 
amount of rock — measured by hundreds of cubic miles in the 
valley of Lake Wakatipu alone — could have been worn down 
and transported to distant places by the slow action of ice and 
water. This difficulty would be removed, could our readers stand 
with us on one of the many lofty mountains which overlook the 
lake, and see far up at its head, amid many mountains less grand, 
the snowy summit of Mt. Earnslaw, on whose sides are blue 
regions of ice; these are the descending glaciers in which lies the 
secret of the valley’s formation. In those streams of ice that 
flow down from the snow-fields of Mt. Earnslaw, vast and irre- 
sistible as they are, we see but the puny remains of a mighty 
Tiver of ice that once flowed through the whole valley of Lake 
Wakatipu, the extent of which was limited only by the ocean, 
which undermined and floated away its extremity in the form of 
icebergs, in the same manner that they are formed at the present 
day on the coast of Greenland. It takes but a glance to con- , 
vince us that this great ice-river was the engraving tool that, 
aided by storm and frost, cut in the living rock the picture of 
Wonderful grandeur and beauty that is spread out before us. 
he glaciers around Mt. Earnslaw are still at work, as they 
have been for ages, in extending the valley. The streams that 
are formed by the melting of the ice are all the year turbid with 
silt, which is the rock that has been ground fine by the glacier, 
the flour from the mill, which they deposit in the upper end of 
elake. In this manner some six or eight miles of the valley 
has been filled up toa height of a few feet above the usual level 
of the lake. We have but to extend the forces now in operation 
on Mt. Earnslaw to the whole valley of Lake Wakatipu, to have 
an accurate and satisfactory explanation of its formation. 
There is another feature of great interest in the history of this 
Valley, first made known by Captain F. W. Hutton, of Dunedin. 
the shore of the lake, about twelve miles above Queenstown, 
