"Hailstone" Rock. 75 



friable nature, rapidly succumbs to the disintegrating influence 

 of the weather, and crumbles away, taking with it the small 

 particles of hornblende, so that the big quartz crystals, when 

 in the last stage prior to being dislodged, are seen standing 

 out in bold relief from the matrix. When this rock is seen 

 projecting in round bosses, through the turfy soil of a hilltop, 

 it looks at a short distance as if strewn with hailstones ; and 

 the illusion is heightened on .observing on its leeward side 

 heaps of loose quartz crystals, which have been completely 

 weathered out from the parent rock, and have been drifted by 

 the wind into this comparatively sheltered situation, as would 

 be the case with hailstones under similar circumstances. 



But the most characteristic feature in the scenery of the 

 western shores of Patagonia is owing to the phenomenon of 

 " soil motion," an occurrence which is here in a great measure 

 due to the exceptionally wet nature of the climate. This 

 slippage of the soilcap seems in this region to be continually 

 taking place wherever the basement rock presents a moderately 

 inclined surface. Some of the effects of this " soil motion " are 

 apt to be confounded with those due to glacial action, for the 

 soilcap takes with it in its downward progress not only its 

 clothing of trees, ferns, and mosses, but also a "moraine pro- 

 fonde " of rock, stones, and stems of dead trees great and 

 small, whereby the hills are being denuded, and the valleys, 

 lakes, and channels gradually filled up. When we first entered 

 the Western Channels my attention was at once directed to this 

 subject on noticing that the lower branches of trees growing 

 in immediate proximity to the sea-shore were in many places 

 withering from immersion in the salt water, and that in some 

 cases entire trees had perished prematurely, from their roots 

 having become entirely submerged. On looking more closely 

 into the matter, I noticed that sodden snags of dead trees, 

 mingled with stones, were often to be seen on the bottom of 

 the inshore waters, and that the beds of fresh water lakes were 



