Mr. Bryce on the Geological Structure of Roseneath. 121 



of the action of the sea, as have been just mentioned in reference to 

 Portkill, are to be seen in the perpendicular cliffs of sandstone, which run 

 nearly east and west for about a quarter of a mile along the south side 

 of the principal approach, and then turn south at a right angle, and 

 gradually subside towards the slopes above-mentioned. 



a Upper-slopes on which the offices stand, perhaps a former leach. 

 b Sea-worn cliff of sandstone, called Wallace's loup. 

 c Terrace, or former beach, on which Roseneath house stands. 

 d Sea level. 



11. Through the kindness of Lome Campbell, Esq., of Roseneath, I 

 am enabled to present a valuable series of levellings of these terraces, 

 which has been made under his directions, and which it is very desirable 

 to have compared with the heights of the other terraces in the Frith, 

 viz. : — 



1. Height of the base of the north portico of Roseneath house 



above high water, --..-. 42 feet. 



2. Base of " Wallace's loup" at the south end, level with the 



above; face of rock 12 feet high, top sloping steeply to 



the west, 42 + 12, 54 — 



3. Lower part of the base of this above high water, 26 feet, 



height of rock at this point, 83 feet, - - - 69 — 



4. Height of the stables, &c. above high water, - - 79 — 



5. Height of a hollow adjoining these buildings, where shells, 



sea-weed, «fcc., were found some years ago, 5 or 6 feet 

 below the surface, .--... 68 



6. Height of the base of the cliffs at Portkill, at the north end 



38 feet; rock, 18i feet, 56^ — 



7. Lower part of the base of the rock, 25 feet ; height of the 



rock, 37 feet, 62 — 



It thus appears that there are indications of terraces and former beaches 

 at still higher levels ; and that the one we are now more especially con- 

 sidering, which marks the last upheaval, presei-ves a pretty equable level 

 round the peninsula, and corresponds with the terraces in Bute. 



I am informed by James Smith, Esq., of Jordanhill, that when the 

 foundation was dug for Roseneath house, shells and sea-weed were found 

 mixed with shingle; and that this shingle consisted chiefly of flat pieces 

 of slate about the size of a penny ; whereas on the present beach the 

 fragments are mostly round. He considers that the whole terrace at 

 this part consists of such marine shingle ; by levelling, the same height 

 was obtained for this beach as that above given. The discovery of these 



