THE ANCIENT ATLANTIS 
275 
Archibald Geikie, we are led to the conclusion that the pre¬ 
sent continental areas must have been terrestrial regions 
of the earth’s surface from a remote geological period. 
Subject to repeated oscillations, continues Sir Archibald 
Geikie, so that one tract after another has disappeared 
and reappeared from beneath the sea, the continents, 
though constantly varying in shape and size, have yet 
maintained their individuality. So far, I think, most 
geologists will agree with Sir Archibald Geikie. It is his 
inference, that the existing ocean basins have probably always 
been the great depressions of the earth’s surface, which has 
not met with such general approval. Dr. Wallace supports 
Sir Archibald Geikie’s view on the grounds, not only of the 
enormous depths and great extent of the oceans, and of the 
circumstance that the deposits now forming in them are 
distinct from anything found upon the land surface, but also 
owing to the supposed extraordinary fact that the countless 
islands scattered over their whole area (with one or two ex¬ 
ceptions) never contain any Palaeozoic or Secondary rocks, 
that is, have not preserved any fragments of ancient con¬ 
tinents, nor of the deposits which must have resulted from 
their denudation during the whole period of their existence! 
The exceptions alluded to by Dr. Wallace* are New Zealand 
and the Seychelles islands, both situated near to continents 
and, according to the same writer, not really oceanic. “The 
vast areas of the Atlantic, Pacific, Indian and Southern 
Oceans are thus left almost without a solitary relict of the 
great islands or continents which some naturalists believe to 
have sunk beneath the waves of these oceans.” Thus writes 
Dr. Wallace. Another argument in favour of the permanence 
of ocean basins has recently been brought forward by Pro¬ 
fessor Joly.f It is based on the facts of solvent denudation. 
He regards the sodium in the ocean as the key to the history 
of solvent denudation, arguing that it was derived from the 
igneous rocks of the earth by the processes of weathering and 
solution progressing throughout geological time. He shows 
that the quantity of oceanic sodium agrees with the sediments 
* Wallace, A. R., “ Island Life,” p. 105. 
t Joly, J., “Radioactivity and Geology,” pp. 127—131. 
T 2 
