712 SUBANTARCTIO ISLANDS OF NEW ZEALAND. [Physiography, Geology. 



The coast-line of the islands, as would be expected in such a storm-exposed 

 land, is bold and precipitous, the western side especially so. For miles it reaches 

 a height of not less than 600 ft., and at times it rises to more than 1,200 ft. in one 

 steep perpendicular face. At one place only, near the head of Port Ross, where there 

 is a narrow cleft, is ascent possible. Magnificent geological sections are thus given 

 of the structure of the island on a line running north-and-south. The cliffs are seen 

 to be composed exclusively of regular flows of basalt and beds of scoria. At their 

 base there sometimes'|lies a talus slope of debris ; sometimes the cliffs run down 

 vertically into deep water, but in many places submerged ledges run out from the 

 shore (fig. 1.) 



This almost inaccessible coast-line was in former times the haunt of the fur- 

 seal. Sealers were lowered by ropes from the tops of the cliffs, and, after despatching 

 their victims, were hauled up with their load of pelts, which they carried down by 

 well-known tracks to the sheltered harbours on the east coast. 



The eastern coast-line is not so high, although it is precipitous in many places. 

 Round the entrance to Port Ross it is very flat, the islands fringing its entrance 

 being but a few feet above sea-level. They form part of a plain of marine denuda- 

 tion which has recently been elevated — part of it, indeed, being just above the sea. 

 These areas grade into the dangerous platforms and reefs which fringe the north- 

 easterly coast. A few stony beaches occur, and inside Enderby Island there is a 

 fine sandy beach fully half a mile in length, extending back from the shore to a line 

 of low dunes. These dunes are composed very largely of shell-remains, great piles 

 of which — mostly Mytilus in a more or less perfect condition — are to be found 

 occasionally on the exposed coast-line of the island. 



Surface Features. 



As a general rule, the highest part of the land is near the western coast-line. 

 It rises at times to just over 2,000 ft. as measured with the aneroid, the highest 

 point of the mainland being in all probability a hill between the head of the North 

 Arm and Western Harbour, just east of Cape Bristow ; but elevations of nearly 

 equal altitude occur near the head of Norman's Inlet, and between it and Carnley 

 Harbour. Adams Island forms a long high ridge, with an elevation of just over 

 2,000 ft. 



Many of the hill-tops are remarkably flat, and are formed of level flows of basalt. 

 Large areas are covered with shallow pools of water, owing to the want of drainage 

 facilities. Here, too, there are signs that the disintegration due to frost-action plays 

 an important part in subaerial denudation. In some places a considerable portion 

 of the loose surface-covering consists of fragments of augite weathered from the 

 basalt. This is specially marked where the last flows are more doleritic in cha- 

 racter and contain numerous large crystals. The sides of these flat-topped hills 

 are frequently precipitous where the edges of the flows have been exposed. Round 

 the head of Musgrave Harbour they form perpendicular faces between 400 ft. and 

 500 ft. high, with splendid examples of vertical basaltic columns. In the northern 

 part of the mainland the elevation is not so great, and the Hooker Hills, between 

 Port Ross and the northern coast, rise to a height of 950 ft. 



The valleys are all occupied by small streams, fed by the prevailing rains and 

 mists, and flow in their upper portion over the solid rock of amphitheatre-shaped 



