ARRAN. GEOLOGY. SCHIST. 357 



rate research, other points of junction both with the granite 

 and the secondary rocks, were it necessary to pursue the 

 repetition of similar phenomena. 



It will be perceived on inspecting the map, that a dis- 

 continuity of the line of schist is indicated between Scri- 

 den and Screeb. There is however little doubt that these 

 rocks exist along the greater part, if not the whole, of that 

 line. But the space between the granite and the se- 

 condary strata is obviously very narrow ; while the state 

 of the superincumbent soil, and the want of precise places 

 of reference, prevent the few points where the schist can 

 be discovered, from being continuously traced or accu- 

 rately laid down. It appeared expedient to leave this 

 tract a blank, rather than, by indicating that which may 

 not perhaps exist throughout the whole, to divert future 

 geologists from examining those places where, if in any 

 part of Arran, the junction of the granite with the se- 

 condary strata will be found. 



Among many failures in the attempts to trace whatever 

 junctions might here exist, arising from causes too well 

 known to practical geologists to require enumeration, I 

 succeeded in discovering that of the schist, both with the 

 granite and the sandstone, near Screeb, in a small but 

 nameless torrent which descends from Goatfell. At this 

 place the junction is characterized by veins proceeding 

 from the granite into the schist, similar to those which 



O f 



occur at Loch Ransa. The body of schist is here very 

 thin, as the secondary strata approach to within a few feet 

 of the granite. This spot presents many interesting parti- 

 culars, and it is much to be regretted that they are so dif- 

 ficult of access, and that the free and tranquil examination 

 of them is impeded by the depth and ruggedness of the 

 fissure, as well as by the incessant falling of the torrent ; 

 impediments of such magnitude that no efforts of art can 

 hope to remove them. The position of the schist is some- 

 what irregular, and in parts vertical ; and it is followed 



