196 LEWIS. GEOLOGY. 



surfaces and ends of the beds. All these inequalities 

 appear as if filled by the conglomerate; which seems 

 to repose on them, occupying all their cavities and 

 assuming the regularly stratified form as soon as it 

 has accumulated beyond these. 



So little of this rock is however here to be seen that 

 it is impossible to decide on the real nature of this 

 connexion. It would be concluded, from its general 

 character, to be analogous to the old red sandstone, 

 and therefore, like the rock with which I have compared 

 it, to be the first of the secondary strata. Yet this opinion 

 is subject to serious doubts. I shall hereafter, in de- 

 scribing the Sandstone islands, have occasion to show, 

 that a red sandstone occurs, not only in these, but on 

 the western side of the adjoining continent, forming 

 a member of the primary rocks. It is probable that 

 the conglomerate of this island is analogous to it, or 

 a portion of the same great deposit ; but as the reasons 

 for this opinion could not be appreciated without anti- 

 cipation, I shall refer the reader to that part of the 

 history of these islands, when he will be enabled without 

 further assistance to form his own judgment on the 

 subject. 



I have reserved for the last place the description 

 of one solitary and anomalous instance of a conglomerate, 

 because its disjointed nature would not admit of its enter- 

 ing into the description of either of the preceding rocks. 

 It is to be seen at Loch Carlowa, where it forms a single 

 bed of no great thickness, reposing immediately on the 

 gneiss, and apparently alternating with that rock. It 

 is elevated at an angle of 45 degrees, and is about 70 

 or 80 feet in height and 50 in breadth, the flat surface 

 being exposed. The gneiss on which it lies and by 

 which it is surrounded, is violently contorted and con- 

 tains an unusual proportion of granite veins ; this 

 confusion forming a striking contrast to its own undis- 

 turbed appearance. That it is actually contained between 



