114 ANCIENT BEACH ON PLYMOUTH HOE. 
From evidences afforded by this neighbourhood, 
or rather by the elevated beaches (which contain 
specimens of shells of existing species) presented 
to view in the cliffs of both south-western counties, 
it would seem that the rise must have been con- 
siderable and temporarily fixed.* The usual height 
* The height of raised beaches referrible to a modern epoch 
varies greatly ; at Coquimbo they are said to be raised above the 
sea 400 or 500 feet : recent shells were found by Mr. Lyell from 
30 to 90 feet above the Baltic. The average elevation in Devon, 
Cornwall, and Somerset, is found by De la Beche to be 40 feet, 
Ancient beach on Plymouth Hoe. Owing to the recent alterations 
on the Plymouth Hoe this object of curiosity has been nearly 
removed. Going however lately (May, 1839) to look for any — 
remnants, I found that at the “ Western Hoe” at an elevation of 
about fifty feet above the present sea, the quarrymen had laid open 
to view a most interesting section of a remaining portion about 
twenty feet in depth ; the circumstances I noted to be as follows :— 
the entire body of the beach rested on smoothened rock ; it sloped 
very gently seawards, that is to say southwards, and had no in- 
clination to dip east or west, as if the upheaving force had tilted it 
to one of those points ; the mass consisted of thin beds or layers, 
from one to four or five inches thick, regularly superposed or stra- 
tified, and varying most systematically from extremely jine sand to 
tolerable-sized pebbles, the several sorts never appearing to exchange 
position, but keeping uniformly to those beds to which they 
belonged in regard ofsize ; each layer formed a solid cake, in- 
creasing in compactness towards the centre of its depth ; the 
layers also were greatly cemented together, but not so firmly as were, 
the components of each distinctive stratum ; the top differed from 
the rest in being several feet thick, and in being composed of sand 
of uniform size, and in great measure loose or incoherent. My 
idea is, that such phenomena different as they are from those of 
present beaches, imply a gradual elevation of the sea—(sinking 
of the land)—a continued series of trifling impulses, whereby 
fresh and varying deposits were with short intervals superposed ; 
that-no tilting to the east or west occurred during this upheaving 
as supposed by some, but that all the elevations betrayed along _ 
the Hoe east and west, are consistently referrible either to one — 
