294 Traiisact ions . — Geology. 



No further depression of the land is permissible with the evidence at our 

 disposal. 



In the above theory I have been obliged to allow for vast changes in the 

 elevation and depression of land, but if we consider that since the deposition of 

 the tertiary sti-ata a large part of Europe has emerged from the ocean, and that 

 tertiary rocks have been elevated to a height of 5,000 feet in Sicily, and, if I 

 remember right, also on the flanks of the Aljjs, it is surely not unreasonable to 

 suppose that changes of equal magnitude may have taken place in the Southern 

 Hemisphere. There can be no dispute that the tertiaries extending fi-om Cook 

 Strait towards Ruapehu and the Kairaanawa range attain an elevation in the 

 interior of the island of 2,700 feet ; and the tertiaries on the eastern side of 

 Tararua reach, in the Puketoi range, a height of fully 2,000 feet. 



If the above theory is a sound one it will be interesting for other observers 

 to link the supposed changes of level with those which may have taken place 

 on the southern side of the Strait. 



The series of ancient valleys on the opposite shore of the South. Island, 

 which now form harbours and sounds from Cloudy Bay to the French Pass, 

 are at once suggestive of depression, and certainly give the idea that Cook 

 Strait is now the base of a synclinal curve, which, on the supposition of tlie 

 correctness of my theory, formerly formed a horizontal line, or possibly an 

 anticlinal curve. 



It will be seen that I have given a liberal allowance of time, for the 

 elevation I suppose must have been previous to the deposition of the older 

 tertiaries. 



That Port Nicholson was formerly a fresh-water lake can be proved with- 

 out the necessity for much elevation, but the peculiar form and denudation of 

 the land, together with the preparation of the valley basin, i"equires, I think, 

 that we must assume a high elevation in former times. 



Akt. XLIX. — ^Not6s on the Glacial Period. By A. D. Dobson, C.E. 

 [Read before the Wellington PhilosojjJiical Society, 22ncl September, 1873.] 

 Ih a former paper,* which was merely a description of glacial remains in the 

 Nelson Province, I suggested that the former extension of glaciers was due 

 either to the much greater elevation of the land above the sea level at that 

 period, or to the existence of land adjoining to the southward. Since writing 

 that paper I have come to the conclusion that the last greatest glacial extension 

 was due to a greater elevation of the land, and that, although other agencies — 



* Trans. N.Z. Inst., Vol. IV., p. 336. 



