220 PROF. J. LOGAN LOBLEY, F.G.S., F.R.G.S., ON 
It is many years since I came to quite other conclusions. 
In 1891 and 1896 at the Oxford and Liverpool meetings of the 
British Association, and to the Geological Society in 1895, I 
showed, I think, conclusively that there had been no appreciable 
shrinkage of the whole globe, or, in other words, no mean 
radial variation since Cambrian times. The elevations and 
depressions that have since taken place I regard as due to 
expansion and contraction of the underlying solid masses 
mainly by increase and decrease of temperature, and that 
these regional secular movements did not affect the general 
rigidity of the planet, which might be practically solid through- 
out. The oceanic depressed areas and the continental elevated 
areas are, it seems to me, original features produced by the 
consolidation of the globe, the consistantior status of Lord 
Kelvin, when there was a very decided shrinkage, and are so 
far permanent that subsequent surface movements have never 
been sufficiently great to obliterate them, but only to modify 
their outlines. 
The conversion of the central Atlantic into a land area would 
require an elevation of the sea bottom of over 27,000 feet, and 
seeing that as the temperature of the lower depths of oceanic 
waters is uniformly about 32° F., or the freezing point of fresh 
water, there is, in this vast body of cold water, a permanent 
cause of non-expansion of the underlying masses, and, 
consequently, it seems to me, that the ocean basins have never 
been obliterated by the elevation of their floors into land areas, 
and that, therefore, the Atlantis hypothesis is untenable. 
On the other hand I cannot accept Wallace’s conclusion that 
the only land connection from the Old World to America was 
at the north, for an amount of elevation such as can be readily 
admitted would "ive land bridges in the southern seas con- 
o o 
neeting the extremities of the southern continents that would 
allow of, I think, not only the migration of the fauna of those 
extremities, but also of animals whose usual habitats were of 
a more tropical character. 
To account for the relations existing between the faunas and 
floras of the southern lands of both hemispheres, H. 0. Forbes, 
in 1893, supposed an Antarctica that connected Australia, New 
Zealand, the Fiji and Mascarine islands with South Africa and 
South America, and in 1895, Hedley, before the Koval Society 
of New South Wales, suggested a somewhat narrow strip of 
land, perhaps, sometimes, broken into islands, with a mild 
climate, extending across the South Bole from Tasmania to 
Tierra del Fuego. Other authors have advocated modifications 
