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THE BRITISH NATURALIST. [August 



appearances which it assumes — one of simple sand rock and a second 

 with a slight admixture of lime, which latter, being more amenable to 

 weathering, takes every opportunity of slipping away, leaving holes on 

 every exposed surface of varying size. A third phase consists of slates 

 of dark hues, and so well displayed on one hillside that the name of 

 Purple Mountain has been assigned to it. A fourth variety is that of 

 a hard solid core, apparently the bottom bed, to which the local name 

 of Glengarif grit is given. All these differences of structure will be 

 met with in an ordinary day's excursion, but it is a very difficult 

 matter to make out the relative position of each stratum in the 

 absence of distinctive fossils. 



What everyone, naturalist or not, may and must comprehend is that 

 this collection of mountain forms was once deposited in horizontal layers 

 at the bottom of a lake or sea. Then came probably what is not so 

 certain — a series of growths or depositions of limestone over the whole 

 distance of fifty or more miles that the Old Red extends from north to 

 south. Possibly over these were superadded sundry coal strata, and on 

 the alteration of the relative level of sea and land, and on the emergence 

 from the water and the elevation into lofty central ridges all these 

 succeeding deposits were swept away with the exception of what is left 

 at the base and on the flanks of the mountains after a duration of 

 disintegration that the mind can hardly grasp. Vast ages have passed, 

 in which three-parts of England at least have been formed, during which 

 these Kerry ranges have been exposed to the full force of the ordinary 

 agencies of denudation. That the hard Old Red succumbed and parted 

 with very much of its mass is evident from the gaps in the strata — the 

 islands — -the disjecta membra of a great formation that are evident on 

 all sides ; but if this be the fate of a rock which seems as hard as 

 adamant in its texture, what chance of survival have layers of soft lime- 

 stone, which admit of solubility in water that is slightly acidulated ? 



Here may be noted what an important office in nature is served by 

 this quality of the solubility of lime. Without it the animal creation 

 would still be in the jelly state. Lime has a rival in silica, with which 

 some plants can coat themselves, but it is an element so difficult in 

 manipulation that we may say its use would be impossible for the 

 formation of either an endo or exo skeleton. Reflect for a moment on 

 the innumerable instances that a substance which here you see before 

 you a solid rock is capable of furnishing the shells and the eggs and 

 the bones of creation by virtue of its capability of being supplied in a 

 liquid state. Where would be the upright part of man if the little ducts, 

 as the poet says, should cease to feed his bones with lime ? Where 

 would be, without this property, those vast masses of limestone strata 

 such as the carboniferous — the chalk — or coral islands, which animal 

 life has been able to construct in all periods of geological history in 



