170 The Scottish Naturalist. 



And tells that the Creator still 



The wonderful procession leads 

 Of all things that are, that have been blest, 



And, being blest, were bid to yield 

 The life He gave them. 



In making a few remarks on the origin of soils, a history of 

 soils is not intended, but as an explanation has been asked ot 

 one or two assertions in a former paper, relative to the origin 

 of " soil " in the Carse of Gowrie, I take this opportunity to 

 explain my ideas of the origin of rocks, or as we will now put 

 it, the origin of soils. 



All sedimentary rocks, and, therefore, soils, have been de- 

 rived from the plutonic rocks, or the crystalline masses of the 

 first-formed solid crust of the globe. These igneous rocks — 

 very various in their aspect — are composed of comparatively 

 few elementary materials, but from these, by means of their 

 chemical attributes, as affecting each other under continually 

 altering conditions, have resulted all that can now be found to 

 partake of the nature of things earthly. 



If granite be taken as a type of these early rocks, its con- 

 stituents are quartz, felspar, and mica ; quartz comprises about 

 one fourth of its bulk, felspar rather more than a half, and mica 

 less than a fourth. 



These granitic rocks were, as soon as formed, subjected to 

 degrading forces that cohesion and chemical attraction or 

 affinity, were powerless to resist ; and from this disintegration 

 has come about, with an economy and simplicity of design that 

 may well astonish us, nearly all that is found in the inanimate 

 world. 



The first or simple results of the disintegration of granite are 

 (if by the sea) beds of sand resulting from the accumulation ot 

 quartz grains near the shore ; micaceous clay-slate beyond the 

 area of sand, the result of the liberated mica, or, mixed with the 

 sand, micaceous sandstone ; and in the deeper parts of the sea 

 beds of clay settling down from the finely disseminated 

 particles of decomposed felspar. If the degradation takes 

 place upon the land by atmospheric agencies, rain, wind, frost, 

 &c, then the result is the same, but the distribution of the de- 

 rived materials is less regular, the quartz and mica accumulating 

 mixed or unmixed in the valley, while the lighter particles of 

 felspar are carried to considerable distances, and scattered 

 abroad with eveiy flood, and even in large quantities borne 





