28 THE SHADOW OF THE WORLD’S FUTURE 
of food-supplies may in this way be increased is obvious. 
It is not easy, however, accurately to determine to what 
extent this will ease the situation. What is known of 
the cod-fisheries shows that the possibilities can easily 
be over-rated, and we are disposed to think that, 
taking into account all the facts, the possibilities of 
exploiting the oceans will not materially alter the 
situation in respect of man’s fundamental needs. 
Moreover, however great within the limits of human 
possibilities this source of food-supply may become, it 
will always, we venture to think, be small as compared 
with land-supplies. The experience of such countries 
as Japan tends to confirm this. 
To obtain a concrete idea of the areas really needed 
for agriculture, for forests, etc., for Man’s various 
needs, unfortunately, we have to depend upon very 
partial statistics. To get these into due perspective, 
it has to be remembered that the earth’s entire surface 
is only 197-05 million square miles, and that the land- 
surface is only about one-fourth of this. More 
accurately, and neglecting some portion of the polar 
areas, it is 52-5 million square miles. Quite a con- 
siderable portion of this, however, is rocky surface 
or it is desert, sandy, or barren. And here, again, 
statistics though good are incomplete. Thus out of a 
recorded total of 24-13 million square miles, about 7-53 
are regarded as productive, 6-25 as unproductive, and 
the nature of the balance of 10-35 is unspecified. 
This recorded total embraced areas the populations 
of which were then roughly 777.6 millions or about 
40-9 per cent. of the world’s total at the time. The 
aggregate area was 46-0 per cent. of the whole. In 
view of this, and having regard to the characteristics of 
the countries not included, the proportions furnished 
by existing statistics may be assumed fairly well to 
represent the total surface of the earth. On this 
assumption we obtain, in millions of square miles, the