90 Mr. Macgillivray's Account of the Outer Hebrides. 



point of view, however, this layer is of little importance, and none 

 of those gravelly or clayey subsoils, so common in the low country 

 of Scotland, under a thin layers of moss, occur in the Hebrides; 

 for which reason, it must be borne in mind, that the methods of 

 improving land so successfully followed there, can never be prac- 

 tised in these islands. 



But the most important soil consists of sea-sand, which forms a 

 belt extending along the whole western coast of the range. It would 

 appear that the bottom of the sea, along the western coasts of these 

 islands, is almost entirely composed of sand, being only in some 

 places interrupted by rocks. The water is seldom deep, and for 

 this reason extensive tracts of sand are laid bare when the tide has 

 receded. Barray is separated from South Uist, and North Uist from 

 Harris, by a shallow channel, the bottom of which is chiefly of 

 sand. Between South Uist and Benbecula, and between the latter 

 and North Uist, there is a channel at high water, of considerable 

 breadth ; but at low water one passes from the one to the other 

 over a tract of pure sand, along which run one or more stripes of 

 water, collected from the dregs of the tide left in the sands, and 

 the rills which enter from the hills. These sands are with pro- 

 priety called fords. In some places, a valley formed between 

 mountains or high land, has been, as it were, filled up by sea sand, 

 so as to form a continuous and almost perfectly level plain. From 

 a pool formed at the upper part by the water from the hills, there 

 issues a stripe, which generally runs along one of the sides of the 

 sand, and the latter is barricadoed on the side next the sea by a 

 ridge of sand, in which there is only a single gap, which aiFords 

 ingress and egress to the tide. 



Numerous bays occur, the beaches of which are also of this sand, 

 and in them it has generally accumxdated in heaps, a little above 

 water-mark. These heaps, having been acted upon by the winds, 

 have furnished the materials of extensive tracts of comparatively 

 level ground, which extend between the shores and the hills. These 

 tracts have but a very small proportion of vegetable soil intermixed ; 

 and although in summer and autumn they are covered with a pro- 

 fuse and highly diversified vegetation, they present nothing in 

 winter but a dreary waste of drifting sand. 



One of the most singular appearances presented by these sands, is 

 when a more or less level expanse, covered with thick verdure, 

 has been corroded by the action of the weather on the side next the 

 sea, so as to exhibit numerous creeks and bays, with sloping and 

 sometimes nearly perpendicular faces. This expanse has at a for- 

 mer period extended towards the sea, from which its indented and 

 abrupt edges may now be at a considerable distance, the inter- 

 mediate space being occupied by loose sand. 



The sand of these shores consists almost entirely of broken shells, 

 and is generally coarse, although it varies greatly in the size of the 

 grain. The coarsest grains are always found at high water-mark, 

 where there is generally a great accumulation of shells. It is not 



