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effect, unless we conceive the present mountain system to have been a great 

 table-land. We are jjreclucled from this supposition, however, by the fact that 

 the high angle at which the rocks lie, determines that from the first upheaval 

 of the mountains there must have been elevation and depression, ridge and 

 valley, as at present. And the denuded material already mentioned has 

 resulted from the widening and deepening of the valleys by glacier and river 

 actions. If we look to the disparity of climate between Labrador and !N"orth- 

 western Europe, on the same lines of latitude, and resiilting from oceanic 

 currents, there can, by analogy, be no difiiculty in supposing such a distribution 

 of land and water in these latitudes as would make a south polar current 

 sweep along the shores of this island, and chill its temperature to the required 

 degree. The equatorial rains, which now nourish the great forests of the 

 western and lake districts, would then descend in snow, and the glaciers would 

 reach their furthest limit. It is remarkable how near our latitude, even at 

 the present time, approaches in locality to the glacial jjeriod. At Dunedin we 

 are only about 1600 miles from the ice precipices of the Antarctic continent, 

 and the glaciers are said to descend nearly to the sea in the Straits of Magellan. 



The glaciers of Otago have not yet been sufficiently explored to ascertain 

 the lowest level of their terminal faces ; but it may be stated that some of the 

 secondary glaciei-s on Mount Aspiring are from 4000 feet to 5000 feet above 

 sea level.* In sheltered situations, some of them will, no doubt, be lower than 

 this. Dr. Haast gives the terminal face of the Tasman Glacier (Mount Cook) 

 at 2774 feet. Forbes gives the terminal face of the Mer de Glace (Mont Blanc) 

 at 3667 feet above sea level. 



The snow line in Otago is from 7000 feet to 8000 feet above sea level. 

 There is a considerable extent of country above this line, the principal part 

 lying between Earnslaw, 9165 feet, and Mount Aspiring, 9949 feet. The 

 intervening ranges of the Forbes and Humboldt Mountains are covered in all 

 their high parts and ravines with snow fields and glaciers. In a bright sun- 

 shine they are so dazzling that it is only with an effort that the eye can rest on 

 them. From the melting of these gTeat snow and ice fields, the Dart, Rees, 

 and Matukituki have their waters. The Makarora and Hunter similarly flow 

 from the glaciei-s in Canterbury. As the supply of these rivers depends almost 

 entirely on the melting of snow and ice, their volume is regulated by 

 temperature. This gives rise to a set of conditions very much the reverse of 

 what obtains with rain-fed rivers. In winter the glacial-fed rivers are very 

 low, especially during frost, while in summer they are high. On a warm 

 summer day, the difference of their volume between morning and evening is 

 very apparent. 



* The largest glacier from the west side of Mount Aspiring descends to 1400 feet 

 above the sea, and the Francis Joseph glacier, from Mount Cook, to within 700 feet. — Ed. 



