A SUMMER RAMBLE AMONG THE HEBRIDES. 121 



merely a prolongation, occurring in the double sandstone bar : 

 it seems to mark to return to my Illustration the line in 

 which the superadded piece of frame has been stuck on to the 

 frame proper. The origin of the island is illustrated by its 

 structure : it has left its story legibly written, and we have but 

 to run our eye over the characters and read. An extended 

 sea-bottom, composed of Old Red Sandstone, already tilted up 

 by previous convulsions, so that the strata presented their 

 edges, tier beyond tier, like roofing slate laid aslant on a floor, 

 became a centre of Plutonic activity. The molten trap broke 

 through at various times, and presenting various appearances, 

 but in nearly the same centre ; here existing as an augitic 

 rock, there as a syenite, yonder as a basalt or amygdaloid. 

 At one place it uptilted the sandstone ; at another it over- 

 flowed it : the dark central masses raised their heads above 

 the surface, higher and higher with every earthquake throe 

 from beneath ; till at length the gigantic Ben More attained 

 to its present altitude of two thousand three hundred feet 

 over the sea-level, and the sandstone, borne up from beneath 

 like floating sea-wrack on the back of a porpoise, reached 

 in long outside bands its elevation of from six to eight hun- 

 dred. And such is the piece of history, composed in silent 

 but expressive language, and inscribed in the old geologic cha- 

 racter, on the rocks of Rum. 



The wind lowered and the rain ceased during the night, 

 and the morning of Monday was clear, bracing, and breezy. 

 The island of Rum is chiefly famous among mineralogists for 

 its heliotropes or bloodstones ; and we proposed devoting the 

 greater part of the day to an examination of the hill of Scuir 

 More, in which they occur, and which lies on the opposite 

 side of the island, about eight miles from the mooring ground 

 of the Betsey. Ere setting out, however, I found time enough, 

 by rising some two or three hours before breakfast, to explore 

 the Red Sandstones on the southern side of the loch. They 



