224 LOWEST, OR OLD RED, SANDSTONE. 



stances which I hope I need not now dwell on, to a 

 reader who has mastered the principles and the facts 

 of this book, indicate tumultuary depositions, as well 

 as gradual ones, and even repetitions of these, depen- 

 dent probably on torrents resulting from antient dis- 

 placements of the strata. And it is also quite con- 

 ceivable that terrestrial alluvia should have been con- 

 solidated into such rocks on the surface of the land of 

 those periods; affording a further explanation of the 

 peculiar forms of many of the conglomerate deposits, 

 and of the absence of stratification in them. 



And if such terrestrial consolidation might occur 

 from water and repose, so might it also from the ac- 

 tion of heat, of which there is abundant evidence from 

 the facts already stated ; constituting another important 

 feature in its theory. These are, its union, amounting 

 to nearly fusion, with granite, gneiss, and micaceous 

 schist : to which may be added that peculiar compact- 

 ness in itself and in its shales, which occurs in the vi- 

 cinity of these rocks, disappearing in the more remote 

 and generally finer strata. Thus, like gneiss and mi- 

 caceous schist, it has suffered the influence of heat 

 when near rocks which are proved to have undergone 

 this; as, in other places and portions, it is a merely 

 aqueous rock, like the later sandstones. And thus are 

 dismissed, or reconciled, if the reader prefers this term, 

 the rival hypotheses of the ultra-igneous and ultra- 

 aqueous sectaries. I trust that I need not now bring 

 this view minutely to bear on the antient condition 

 and changes of the primary strata, nor on the relations 

 which it possesses to organic fossils. A system of 

 philosophy which trusts nothing to the reasoning of 

 its readers, will not make many philosophers. 



