348 THE VOYAGE OF H.M.S. CHALLENGER. 



the glaciers, descending the valleys into Whale Bay Irish Bay, &c. The glacier, visited 

 from Whale Bay ended in a steep wall of ice about 70 feet high, and at its foot, partly 

 underlying it, was a small lake, supplying a rapid brook flowing into the sea. The glacier 

 next south of that descending into Whale Bay slopes gradually, and feeds a stream, hidden 

 by the ice, which only betrays its existence by the noise of the falling water. It is full 

 of crevasses, caused probably by the sharp curve of the mountain slope, which renders 

 travelling on it difficult and dangerous, as the explorer has frequently to jump across these 

 crevasses. The glacier descending into Irish Bay fills the whole valley about 200 feet 

 above the sea level. All these glaciers show distinct traces of having receded, for the 

 furrows left by them on the rocks of the lower parts of the valleys can be traced distinctly. 



On the western side of the island there is still an active volcano, while a mineral 

 pitch has been met with, and petroleum and hot water springs, the temperature of which 

 is said to be high, have been found by the sealers. 



From a ship anchored in Christmas Harbour an excellent general view of the 

 arrangement of the rocks can be obtained ; they are seen to be arranged in apparently 

 perfectly horizontal beds, the separating lines of the different beds being easily traced 

 all round the harbour. Where the sides are not precipitous, the summit of the ridge is 

 attained by a series of terraces, and it is, as might have been expected, almost perfectly 

 flat. The continuity of the flat-topped surfaces, both of the northern and of the southern 

 ridges, is broken by the two most conspicuous objects in the landscape, namely Table 

 Mountain on the north, and Mount Havergal on the south. This rock-mass does not project 

 above the horizontal hilltop but rather appears to stand out from it like a huge boulder. 

 The summit of the ridge is formed of the ordinary bedded rock, this "neck" of con- 

 glomerate not reaching any greater height than that of the contiguous parts of the ridge. 

 These hills belong to a class representatives of which were found again in the south in 

 Greenland Harbour, and as they resemble each other closely they will be described 

 together. In both places they protrude through the horizontal beds of basalt, without 

 having caused any apparent disturbance in the arrangement of the beds whicli surround 

 them. The horizontal beds which form the mass of the land are basaltic, and vary from 

 10 to 20 feet in thickness, being generally compact ; but in ascending the hill, beds an 1 

 frequently met with which contain large amygdaloid cavities filled with zeolites, principally 

 analcite and stilbite. These minerals are very plentiful in this part of the island, and 

 when rounded by the action of water form remarkable white pebbles on the other- 

 wise dark-coloured sand. Up to the summit the alternation of beds of compact sub- 

 columnar rock of amygdaloid is pretty regular. The amygdaloid is of two kinds ; in one 

 the cells are small, very thickly disseminated, and completely filled up by a zeolitic mineral ; 

 the other has larger cavities, less thickly spread, and generally only coated with crystals, 

 while seams filled with crystalline matter are also frequently met with. The cavities 

 contain generally analcite, the seams stilbite. The ridge on the southern side is higher 



