1834.] GLACIERS AND THE SNOW-LINE. 247 



Chile, on the other hand, a little northward of Concepclon, 

 the sky is generally clear, rain does not fall for the seven 

 summer months, and southern European fruits succeed 

 admirably ; and even the sugar-cane has been cultivated.* 

 No doubt the plane of perpetual snow undergoes the above 

 remarkable flexure of 9000 feet, unparalleled in other parts 

 of the world, not far from the latitude of Concepcion, where 

 the land ceases to be covered with forest-trees ; for trees in 

 South America indicate a rainy climate, and rain a clouded 

 sky and little heat in summer. 



The descent of glaciers to the sea must, I conceive, 

 mainly depend (subject, of course, to a proper supply of 

 snow in the upper region) on the lowness of the line of 

 perpetual snow on steep mountains near the coast. As 

 the snow-line is so low in Tierra del Fuego, we might 

 have expected that many of the glaciers would have reached 

 the sea. Nevertheless I was astonished when I first saw 

 a range, only from 3000 to 4000 feet in height, in the 

 latitude of Cumberland, with every valley filled with 

 streams of ice descending to the sea-coast. Almost every 

 arm of the sea, which penetrates to the interior higher 

 chain, not only in Tierra del Fuego, but on the coast 

 for 650 miles northwards, is terminated by "tremendous 

 and astonishing glaciers," as described by one of the 

 officers on the survey. Great masses of ice frequently 

 fall from these icy cliffs, and the crash reverberates like 

 the broadside of a man-of-war, through the lonely channels. 

 These falls, as noticed in the last chapter, produce great 

 waves which break on the adjoining coasts. It is known 

 that earthquakes frequently cause masses of earth to fall 

 from sea-cliffs : how terrific, then, would be the effect of 

 a severe shock (and such occur here)t on a body like a 

 glacier, already in motion, and traversed by fissures ! 

 1 can readily believe that the water would be fairly beaten 

 back out of the deepest channel, and then returning with 

 an overwhelming force, would whirl about huge masses 

 of rock like so much chaff. In Eyre's Sound, in the 

 latitude of Paris, there are immense glaciers, and yet the 

 loftiest neighbouring mountain is only 6200 feet high. 



* Miers's "Chile," vol. i., p. 415. It is said that the sugnr-cane grew at 

 Ingcnio, lat. 3a* to 33°, but not in sufficient quantity to make the manufacture 

 profitable. In the valley of yuillota, south of Ingenio, 1 saw some large dat-- 

 palm-trees. 



t Hulkelcy's and Cummin's " Faithful Narrative of the 1-oss of the IVaf^er." 

 The earthquake happened Aufrust ajth, 1741. 



