Ancient Glacier's of New Zealand. 255 



The evidences of a great extension of the glaciers of New 

 Zealand in past time, are furnished by the following consid- 

 erations : — 



(1.) Immense moraines surround the mountains on every 

 side, and are found far below the terminus of the existing 

 glaciers, — in many cases reaching the level of the sea. Some- 

 times the narrow valleys are crossed by a huge bank of con- 

 fused glacier- worn material, brought down and deposited as 

 a terminal moraine by a glacier that has long since passed 

 away. These old moraines, by forming dams across the 

 valleys, sometimes give rise to extensive lakes. On the 

 East Coast of the South Island, the Plains of Canterbury, 

 which extend along the foot of the mountains for a distance 

 of a hundred miles, and are fifty miles wide at the center, 

 are regarded by Dr. Haast as composed of the material that 

 has been brought out of the mountain valleys by the ancient 

 glaciers. ' On the West Coast, the country is described by 

 the same writer, and by other intelligent travellers, as being 

 entirely covered with huge moraines, that extend from the 

 sea coast — where they have frequently been cut away by the 

 waves, so as to form steep walls and precipices — far up the 

 valleys, to the foot of the existing glaciers. Through this 

 immense layer of glacier-worn debris, the present streams 

 have excavated their channels. 



(2.) Scattered throughout the valleys are found huge 

 boulders, which usually differ in the nature of their material 

 from the rocks of the surrounding cliffs, and are frequently 

 eighty or a hundred miles lower down the valleys than the 

 present glaciers extend. These transported boulders are 

 sometimes of great size, often measuring thirty to forty feet 

 in diameter. 



(3.) Another indication of the magnitude of these ancient 

 streams of ice, is to be found in the extent of the great val- 

 leys that they have worn out in the sides of the mountains. 

 These are far too large for the streams that now flow through 

 them, and they frequently bear on their rocky walls the well 



