﻿1848. FURROWED LIMESTONE. 295 



a fissure. Though the layers of the limestone are 

 most extensively detached by the freezing of the 

 moisture, which insinuates itself between them, 

 such a process could not produce any thing so 

 regular as this small anticlinal ridge. If beds 

 already fissured were, in subsiding, to be pressed 

 more closely together, the edges of the fissure 

 might perhaps assume such a form. Elsewhere, in 

 the same formation, straight furrows, as if drawn 

 by a plow, are common, and evidently proceed 

 from the small fragments which cover the ground, 

 filling a crack, nearly to the brim. Judging from 

 the whole surface here being covered with thin 

 pieces of limestone to the exclusion of soil, I 

 should infer that the frost splits off the layers and 

 breaks them up more effectively than any agent to 

 which rocks are exposed in w^armer climates, and 

 that the scantiness of the soil is owins^ to the 

 shortness of the season of growth of the lichens 

 and other plants, which have the power of decom- 

 posing the surface of the stones and so producing a 

 little mould. The frost breaks up the stone before 

 the lichens have time to establish themselves. 



The limestone which forms the cliffs of Cape 

 Krusenstern, and the other cliffs on the coast 

 bet\\^een it and Cape Kendall, contains many thin 

 slaty beds of chert or quartz rock, either bluish- 

 white, or coloured reddish-brown by oxide of iron. 



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