168 Clement Eeid — On Dmt and Soils. 



utterly bare of vegetation, but so flat that they evidently could not 

 have been bared by the action of rain. During the summer these 

 bare places had been looked upon simply as evidence of the extreme 

 poverty of the soil ; but happening to be on the Moor during a 

 severe frost and easterly breeze, I vi^as surprised to find the frozen 

 shale blowing awray in small clouds of dust, having been finely 

 divided by the frost. Tufts of heather may thus be left projecting 

 higher and higher above the soil, till they are undermined and 

 destroyed, and the bare patch increases. On the other hand, a mild 

 season may allow the plants to re-take their old dominion, and pre- 

 vent any movement of the soil for many years. 



At first sight what takes place on a moor a thousand feet above 

 the sea, may seem to have little connection with the oiigin of the 

 present soils of the lowlands of England. But, a few thousand 

 years ago the climate was much colder. During this period the 

 vegetation of the lowlands corresponded with that now found on our 

 highest mountains — as is clearly proved by the occurrence of the 

 Betida nana as a fossil in various parts of England, though this 

 plant is at present confined to the mountains of Scotland. The 

 climate being colder, the vegetation died down much more in winter 

 and the close matted turf which now so efi'ectually binds the soil, 

 was replaced by a thin scrubby covering of dwarf birch and willow. 

 The more exposed tracts were probably unprotected by vegetation, 

 as is the case in many parts of the Arctic regions. Not only was the 

 climate colder, but great part of the North Sea being land, the east 

 winds were sharper and drier-. 



It is, I believe, to the keen east winds of spring that we owe in a 

 great measure the fertility of our country. 



This may seem an extraordinary conclusion ; but if one examines 

 analyses of rocks, it is curious what an exceedingly poor soil the 

 decomposition of the majority of them would yield. Some one or 

 two essential ingredients are missing, though everything else may be 

 there. To make a good soil a mixture of material from different 

 rocks is usually necessary. In alluvial flats or on hill-sides this 

 mingling is done by running water ; but up-hill, or over dry sands, 

 or pervious rocks, the wind only can act. That it did act much 

 more effectually at a former period necessarily follows from what we 

 know of the climate. 



Leaving out of account for the present the wide-spread Loess 

 deposits, which Baron von Itichthofen refers to the agency of the 

 wind,^ I think that we can find, even in England, abundance of 

 evidence of its action : evidence that has been overlooked from its 

 very familiarity. In high-lying Chalk districts we constantly find 

 hollows filled with loam and sand, more or less stratified, full of 

 small roots, but without other fossils. It is clear that these could 

 not have been deposited by water, for the rain would immediately 

 sink into the porous Chalk. Former iEolian action seems also 

 evidenced by the abundance of land shells in other similar hollows. 



^ Op. cit. 



