Mr. Macgillivray's Account of the Outer Hebrides. 89 



range, in fact, peat soil is to be seen at the very summits, and in 

 all intermediate situations, down to the shores. It is also a preva- 

 lent opinion that peat is formed chiefly of decayed trees ; but in 

 none of the numerous varieties of peat met with in the Outer He- 

 brides, have I seen any indications of such an origin. 



The most common kind of peat in these islands is of a spongy 

 texture, composed almost entirely of the roots of Scirpus ccespito- 

 sus, Carices, Junci, and Eriophora. It is generally more or less 

 continuous at the surface, and generally occupies the gentler slopes 

 and lower tracts. The pasturage yielded by the plants of whose 

 partially decayed roots this variety of peat is formed, is well adapt- 

 ed for summer grazing, and the moors of this description are the 

 most valuable in the Hebrides, although in winter they are gene- 

 rally wet. 



^Beneath this more spongy peat, there is generally a layer, more 

 or less deep, of a darker, more compact, and less fibrous kind, from 

 which the natives extract their fuel. Peat of this kind also occurs 

 in the lower parts of valleys and hollows, where it presents an irre- 

 gular surface, formed of tufts of heath elevated above the general 

 level, surrounded by mud, and in winter generally converted into 

 islands. The pasturage in these low bc^s is of the worst descrip- 

 tion, and cattle not unfrequently perish by sinking in the mud, as 

 they attempt to pass from one tuft to another. The lower tracts 

 of Lewis and North Uist present abundant examples of this kind 

 of soil. 



When the depth of soil is not great, and the declivity consider- 

 able, the peat is generally of a light brown, somewhat earthy appear- 

 ance, friable when dry, and much impregnated with iron, leaving 

 a great quantity of reddish ashes when used as fuel. The common 

 ling, and in many places Erica cinerea, are the predominant 

 plants which this variety yields. Towards the summits of the moun- 

 tains, again, where the peat is still thinner, the pasturage is gene- 

 rally better, consisting of Carices, Junci, and Scirpi, with less 

 heath, and numerous alpine plants. 



The aspect of the vegetation, however, is little diversified over 

 the whole range of islands, although a very long list of species, be- 

 sides those mentioned, might be made out. Ling, heath, and Ca^ 

 rices, are every where the prevailing plants. In some parts Melica 

 ccerulea is extremely abundant, and although rather a rank grass, 

 aflTords good pasturage for cows and horses. 



When the peat soil is mixed with the clay or grit which has ori- 

 ginated from the disintegration of the gneiss rocks, the vegetation 

 is greatly improved, presenting a copious intermixture of grasses 

 and other plants. 



The clayey soil which occurs in some of the valleys, and along 

 the declivities, seldom presents itself unencumbered by peat, and is 

 hardly deserving of particular notice. It however forms a stratum 

 intermediate between the rock and the peat soil of the surface, ex- 

 tending over considerable portions of the islands. In an agricultural 



VOL. II. M 



