RAISED BEACHES AND THEIR ORIGIN. 171 
action, and the terrace would form a raised beach, in the true 
sense of the word. 
We must be careful to note the distinction between the 
beach and the cliff (or bank) which forms its inshore bound- 
ary. Both are frequently found together, and in cases, some 
of which I shall cite, several of these cliffs, with their 
attendant beaches, are now to be found elevated far beyond 
the present limits of the tides. At the same time each may 
be found without the other. There are instances where, in 
the same cliff which is now washed by the waves, the former 
sea-level is marked by caves which are now beyond the reach 
even of the spray. The probabilities are, however, that at 
the period of elevation, a beach of shingle descended from the 
entrance of most of these caves, which has since been worn 
down and removed by tidal action ; and thus the old and the 
new coast -lines are united. It is evident that the further 
action of the waves would, in process of time, obliterate all 
traces of the earlier coast-line. On the other hand, remains 
of old sea-beaches, in the form of gravel and sand, with shells, 
are sometimes found in isolated patches, in places where the 
former coast-line is so far distant as not to be recognised. In 
cases where there are several cliffs, with their terraces rising 
in tiers, one above the other, such steps show (as Sir C. Lyell 
has pointed out) so many pauses in the process of elevation of 
the coast. Had the rise of the land been continuous and uni- 
form, there would have been no prominent line of cliff, 
supposing the rock to be of uniform texture ; for every portion 
of the surface having been in its turn, and for an equal period 
of time, a sea-shore, no part could be more indented or eroded 
than another. But if pauses occur during the upheaval, the 
waves and currents have time to undermine and remove masses 
of rock at certain stages, and thus produce ranges of cliffs 
with terraces at their base. 
The evidence of the former action of the sea along lines of 
coast now far beyond the reach of the waves, is of so satisfac- 
tory a kind, from the indirect evidences we have been con- 
sidering, that it is scarcely strengthened by the presence of 
sea- shells, corals, and crinoids in the gravels of the raised 
beaches. These, however, are not uncommon; and what is 
still more interesting, works of art and human remains have 
also been found associated with them, attesting that in some 
cases the elevation of the land has taken place since the time 
that man was an inhabitant, and navigated the shores and 
creeks in his canoe. Sir H. De la Beche has mentioned in his 
“ Report on the Geology of Devon and Cornwall,” that in 
mining gravel for tin, at Pertuan, in Cornwall, skulls and 
works of art were found lying at a depth of 40 feet from the 
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