Hurton.—On the Formation of Lake Wakatipu. 395 
to show evidence of it by some, at least, of the rivers being deflected to the 
north ; but the very contrary is the case, for the Jacobs River, Oreti, and 
’ Mataura have all been deflected towards the south. The evidence, indeed, of 
the river system goes to show that the central part of the South Island has 
been more elevated than the southern part, a movement which must have 
tended to empty Lake Wakatipu. 
The next supposition that we can make is that this unequal elevation and 
depression was not universal but local, the country north of Lake Wakatipu 
having alone been depressed. If, however, this local depression occurred 
between the head of the lake and the west coast it would have emptied Lakes 
Wanaka and Hawea which lie north of it ; and if the depression was north of 
Lake Wanaka it would have emptied, in the same way, Lakes Pukaki and 
Tekapo, which are further north again, for all these lakes lie in a more or less 
north and south direction, with the south end dammed up. There appears, 
however (Hochstetter’s “New Zealand,” p. 484), to be one place, off Cliffy Head, 
from which many of these lakes radiate, so that if the depression had taken 
place there it might perhaps have formed them all. But if we assume this, we 
again encounter those difficulties that I at first pointed out ; for by this theory 
the central part of the Island must have been depressed at least 15,000 feet 
more than the north and south, and the deep sounds instead of being found on 
the south-west of Otago and the north of Marlborough, should occur in 
Canterbury, and the rivers should be deflected to the north in Otago, and to 
the south in Nelson and Marlborough ; for the fact of all the rivers on the 
Canterbury plains having cut deep gorges through the alluvial deposits, shows 
clearly that their volocities have not been reduced by a greater sinking of the 
west than of the east coast. The Nelson lakes, moreover, would require some 
different arrangement again to account for them. 
We may still make a third supposition as to the formation of Lake 
Wakatipu by supposing it to be owing to a small local subsidence in that 
area alone, but this is disproved by the regularity of the strike of the rocks 
from one end of the lake to the other, and the dip of the beds is so slight that 
any movement by which the upper or central portion of the lake had been 
depressed could not possibly escape detection, and I had this constantly in my 
mind when examining the district last summer. 
In order, therefore, to explain the formation of these lakes by unequal 
subsidence, and at the same time to account for other phenomena observed 
round the coast, we should have to imagine such a complicated system of local 
depressions and upheavals that they would more resemble the contortions 
produced by lateral pressure than any movements that we know, or have any 
right to assume, are going on at the surface of the earth. 
In the section given by Dr. Hector (Trans. N.Z. Inst., IT., p. 372) we see 
