26 
W. Pengelly on the Bed Sandstones, 
stone without marl, but interstratified with thin beds of very hard 
and compact conglomerate, altogether unlike the " pebble bed," 
and differing almost as much from the breccias south of the Exe. 
Cross or diagonal stratification frequently occurs in even compara- 
tively coarse conglomerates as well as in the sandstone, and the 
botryoidal and other concretionary forms are very prevalent. 
Whilst the Triassic coast has everywhere retreated before the 
sea, there are in different districts peculiarities in the modes of 
retrocession. In Torbay the waves have formed numerous caverns 
in the cliffs, near Dawlish they have left comparatively small insu- 
lated masses as mementoes of an ancient coast-line, and at the 
Straight Point, by a concentration of their powers, they have hol- 
lowed out a cavern about 70 feet long, and, at the entrance, 12 feet 
wide by 10 feet in height. But east of this point, for a distance of 
from five to six miles, there are neither caves nor islets ; a few 
salient points, such as Otterton Head, have offered a sturdier 
resistance than usual to the encroachments of the sea, but 
generally the coast has fallen back with tolerable uniformity. In 
Ladrum Bay, however, about two miles from Sidmouth and imme- 
diately west of the hill known as the High Peake, there is a com- 
bination of the Torbay and Dawlish characteristics, A group of 
islets occupies the bay, and in some of them caverns have been 
scooped out, whilst others are completely tunnelled : the effect of 
the whole is singularly picturesque. 
East of the " Pebble Bed " there is but little marl in the cliff 
section until reaching Ladrum Bay, where a small patch caps the 
red sandstone. In consequence, however, of a vertical fault, which 
throws the country down on the wdet, or raises it on the east, to the 
amount of probably about 50 feet, it disappears almost imme- 
diately ; but, on account of the rapidity with which the cliff springs 
up on the east of the fault to form the lofty High Peake, the marl 
is again brought in, and over it lies the most westerly Greensand 
outlier which appears on the immediate coast. This again is capped 
witli Stipracrctaceous gravel ; lu nce this single hill represents not 
