30 Transactions. 



few miles. This submarine bank or shelf no doubt marks the- 

 utmost eastward extension of the land since Pliocene times. 

 The fan of the Rakaia and Ashburton at one time stretched 

 further east than the present coast-line, as pointed out by Sir 

 Julius von Haast. This would probably have been so extended 

 during a period when the land was at a higher level. On de- 

 pression setting in, the outer segment of the fan was swept 

 away owing to its being exposed to the full force of the heavy 

 seas and the strong northerly drift on the coast ; and this would, 

 no doubt, contain that portion where the streams were actively 

 aggrading their beds. In the case of the Waimakariri, however, 

 this portion has only been submerged, not actively eroded, 

 owing to the protection afforded by the volcanic mass of Banks 

 Peninsula and its submarine easterly and north-easterly exten- 

 sion. Soundings marked on charts show this extension, and also 

 show that the depth increases very gradually from the mouth 

 of the Waimakariri for some distance out into Pegasus Bay. 

 The coast-line here is not marked by any cliff such as occurs 

 on that part of the Ninety-mile Beach near the mouth of the 

 Ashburton River and on the coast near Oamaru. In this place 

 erosion of the coast-line by the action of the waves is extremely 

 rapid, and threatens serious loss in the near future unless ade- 

 quate protection is given. 



An elevation of even 600 ft. would have considerable eff-vt 

 on the climate of the country. In the first place, it would 

 largely increase the extent of country above the snow-line, and 

 hence cause a great extension of the glaciers. The present 

 terminal face of the Tasman Glacier is 2,460 ft. above sea-level ; 

 an increased height of the land of, say, 600 ft. would bring it 

 down nearly to the upper end of Lake Pukaki, which is 1,550 ft. 

 above sea-level — that is, supposing the glacier would reach the 

 same distance above sea-level in time of high land as of low 

 land. This supposition may not be strictly accurate, as it is 

 quite possible that the glacier would come down further owing 

 to the increased accumulations of snow; but even if not, the 

 effect of the elevation would still be very marked. 



The effect of high land is easily seen on comparing the size 

 of the glaciers at the head of the Waimakariri and Rakaia with 

 those near Mount Cook. Even allowing for the increased 

 average height of the peaks in the last-named locality, the 

 glaciers are of enormously greater importance and come down 

 to a much lower level. The height of the terminal face of the 

 Tasman Glacier is 2,460 ft., while that of the Lyell Glacier at 

 the head of the Rakaia is 3,568 ft., and that of the Waimakariri 

 4, 1 62 ft. above sea-level. 



It is possible, therefore, that, owing to increased snowfall 



