66 COLONSAY 



trenches that are made in cutting peat for fuel are seen, 

 in the course of years, to be filling up. When cutting is 

 done, the top spit with the covering vegetation is removed 

 and laid aside ; after the available layers of peat have 

 been removed, it is set back in the bottom of the trench. 

 Although the growing process of the peat is noticeable in 

 moist places, it is not so apparent on the dry hill-tops. 



Besides those already enumerated, many intermediate 

 grades of soil are to be met with throughout the island 

 dark, hazel and yellow loams, soils containing a large propor- 

 tion of humus, and others of a sandy nature, with possibly 

 small areas of calcareous soils in Uragaig and some other 

 places. There is no available record of the soils having 

 been analysed. One of the most fertile loams in the island 

 has been formed by the decay of the "Scalasaig granite." 

 " Much of the fertility of the districts bordering on the sea 

 is derived from shelly sand which the Atlantic supplies 

 more or less abundantly to all the islands of the Inner and 

 Outer Hebrides. This sand supports a beautifully green turf, 

 which in summer time is gay with wild flowers, affording 

 colour effects for which the landscape painter may search 

 the pasture-lands of the mainland in vain. The greater 

 part of Oransay is of this character." 1 



Landscape and scenery are largely dependent on geological 

 structure. Hard rocks resist disintegration and form hills, 

 while the softer and more destructible materials crumble 

 away into hollows and valleys. Every prattling stream that 

 finds its way to the sea assists in the process of landscape 

 sculpture. The running water carves out the hollows and 

 the valleys by cutting and grooving the channels of the 

 streams deeper and ever deeper, carrying away the loosened 



1 "Notes on the Geology of Colonsay and Oransay," by James Geikie, 

 LL.D., F.R.S., F.R.S.E., etc., of H.M. Geological Survey (Tramactions 

 of the Geological Society of Glasgow, vol. vi. part ii., 1878-79, 

 1879-80). 



