18 CORNISH POST-TERTIARY GEOLOGY. 



rock in the vicipity exhibit planed surfaces at about 6 feet above 

 high-water mark, being probably remnants of the old beach bed. 



During the accumulation of the Head in this section, the beach 

 appears to have been mixed with it. 



In the Cove near Eosemullion Head, to the south of Bream, the 

 cliffs exhibit — Head of yellowish and brown loam, with angular 

 stones, on — blackish and brown sand, with quartz pebbles, 4 to 

 5 feet in thickness, and from 5 to 10 feet above high-water mai-k. 



In Coverack Cove, the cliff to the north of the village is composed 

 of brown earthy sand with angular stones (the distribution of which 

 gives an appearance of bedding), upon — sand, with pebbles and 

 boulders of th6 neighbouring rocks, at base about 8 feet above high- 

 water mark. To the north of the above, 5 to 12 feet of buff and 

 greyish loamy sand, with iron-stained bands, contains pebbles and 

 boulders, in places, at its base from 5 to 10 feet above high-water 

 mark. I 



In Porthbeer Cove, to the south of Coverack, pebbles and large j 

 boulders of diallage rock, and occasional small flints, in brownish 

 earthy loam, occur at about 10 feet above high- water mark. The 

 face of the low cliffs is composed of brownish sand, probably blown 

 against them. 



Between Trewavas Head and Porthleven, south of Tremearne 



houses, the cliff section shows : 



Grey loamy soil, with flint and quartz pebbles 2ft. 



Grey loam, with angular slate and granite fragments of rather 



small size 3ft. to 5ft.' 



Grey loam, with angular fragments of slate and granite, and 



rough granite boulders 5ft. to 6ft. 



resting upon nearly horizontal grey slates with quartz veins, at 



from 12ft. to loft, above high-water mark. 



(Fig. 11.) The low cliffs between Pra and Sydney Cove are com- 

 posed of Head, with the exception of the upper part, which consists ( 

 of blown sand 2 to 3 feet in thickness. In one place, where the 

 cliff is about 14 feet in height, a trace of consolidated blackish sand, 

 made up chiefly of comminuted slate fragments, is visible at the 

 base of the cliffs about 2 feet above high-water mark ; it is overlain 

 by 12 feet of coarse granitic loam, containing angular fragments of 

 slate, granite, and quartz, and some subangular boulders. 



Toward Sydney Cove the cliff becomes lower, and the Head 



