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hills. Of soils, too, in the stricter sense of the word, there is a 

 notable variety. The general division of earths into sandy, loamy, 

 clayey, and so forth, is loose, and for scientific purposes inaccurate ; 

 distinctions far more natural, as well as valuable, are furnished by 

 the nature of the rocks, whose decomposed materials form the soil. In 

 Arran the variety of the geological formations produces a correspond- 

 ing diversity in the composition of the earths ; and though we are no 

 doubt still greatly in the dark as to the influence of soil on the 

 habitat of plants, there can yet be little doubt that the diversity of 

 soils furnished by the granites, traps, porphyries, slates, sandstones, 

 shales, and limestones, must exercise a powerful influence on the flora. 

 Whatever may be the importance of these conditions generally, 

 they certainly exist here in a remarkable degree. 



To these advantages of geographical position and physical char- 

 acter is to be added the scarcely less important one of climate. 

 Lying off the west coast of Scotland, and thus almost in the 

 Atlantic, Arran enjoys a copious rain -fall, while its insular position 

 preserves it from those extremes of heat and cold which are so inju- 

 rious to vegetation. Hence it is that the climate, while in many 

 parts quite cold enough for the ordinary plants of Britain, and 

 while the mountains rise high enough to be a fit habitation for seve- 

 ral alpine species, is yet sufficiently mild and equable for the growth 

 of some usually found in more southerly regions. These conditions 

 exist also in the extreme point of Cantyre ; and accordingly we find 

 Campbelton enjoying the mildest winter in Scotland, and many ten- 

 der species flourishing there in the open air. 



The effect of climate on the flora of Arran is twofold, it increases 

 the number of species, and it imparts a general vigour and luxuriance 

 to the vegetation, which makes it interesting to the lover of the 

 landscape picturesque, no less than to the botanist. Every one must 

 have observed how much of the peculiar charm of Arran scenery is 

 owing to this circumstance. The bright green of the fields and 

 pastures, the woods that fringe the shore and cling to the slopes of 

 the lower hills, add grace and soft beauty to landscapes that would 

 otherwise be severe and gloomy in their grandeur ; and while they 

 pleasingly relieve the monotonous gray of the granite mountains, 

 serve to heighten by contrast the effect of the bare crags and jagged 

 peaks that rise behind them. In spring or early summer, when the 

 grass sprouts fresh on the hill-sides, and the varied foliage of the 

 trees still preserves the delicate green of youth, or in July, when the 

 lower ridges are purple with the rich heather-bloom, this variety 

 of colour is finest, and this is the best time to see Arran scenery in 



