OcTOBER 2, 1913] 
NATURE 
151 
_ become more and more apparent that few of the physical 
and biological sciences have not received contribu- 
tions, and important contributions, of new facts; and 
also that problems concerning the distribution of the 
different groups of phenomena and their action and 
reaction upon one another—the problems which are 
specially within the domain of the geographer—have 
not merely been extended in their scope but have 
been helped to their solution. 
The reaching of the two poles of the earth brings 
to a close a long and brilliant chapter in the story 
of geographical exploration. There is still before us 
a vista of arduous research in geography, bewildering 
almost in its extent, in such a degree indeed that 
“the scope of geography”’ is in itself a subject of 
perennial interest. But the days of great pioneer 
discoveries in topography are definitely drawn to their 
close. We know the size and shape of the earth, at 
least to a first approximation, and as the map fills 
up we know that there can be no new continents and 
no new oceans to discover, although all are still, in a 
sense, to conquer. Looking back, we find that the 
qualities of human enterprise and endurance have 
shown no change; we need no list of names to prove 
that they were alike in the days of the earliest ex- 
plorations, of the discovery of the New World or of 
the sea route to India, of the “Principall Naviga- 
tions,’ or of this final attainment of the Poles. The 
love of adventure and the gifts of courage and endur- 
ance have remained the same: the order of discovery 
has been determined rather by the play of imagina- 
tion upon accumulated knowledge, suggesting new 
methods and developing appropriate inventions. Men 
have dared to do risky things with inadequate ap- 
pliances, and in doing so have shown how the 
appliances may be improved and how new enter- 
prises may become possible as well as old ones easier 
and safer. As we come to the end of these “ great 
explorations,” and are restricted more and more to 
investigations of a less striking sort, it is well to 
remember that in geography, as in all other sciences, 
research continues to make as great demands as 
ever upon those same qualities, and that the same 
recognition is due to those who continue in patient 
labour. 
When we look into the future of geographical 
study, it appears that for some time to come we shall 
still be largely dependent upon work similar to that 
of the pioneer type to which I have referred, the work 
of perfecting the geographer’s principal weapon, the 
map. There are many parts of the world about which 
we can say little except that we know they exist; 
even the topographical map, or, the material for 
making it, is wanting; and of only a few regions 
are there really adequate distributional maps of any 
kind. These matters have been brought before this 
Section and discussed very fully in recent years, so I 
need say no more about them, except perhaps to 
express the hope and belief that the production of 
topographical maps of difficult regions may soon be 
greatly facilitated and accelerated with the help of 
the new art of flying. 
I wish to-day rather to ask your attention for a 
short time to a phase of pioneer exploration which 
has excited an increasing amount of interest in recent 
years. Civilised man is, or ought to be, beginning 
to realise that in reducing more and more of the 
available surface of the earth to what he considers a 
habitable condition he is making so much progress, 
and making it so rapidly, that the problem of finding 
suitable accommodation for his increasing numbers 
must become urgent in a few generations. We are 
getting into the position of the merchant whose trade 
premises will shortly be too small for him. In our 
case removal to more commodious premises elsewhere 
seems impossible—we are not likely to find a means 
of migrating to another planet—so we are driven to 
consider means of rebuilding on the old site, and so 
making the best of what we have, that our business 
may not suffer. 
In the type of civilisation with which we are most 
familiar there are two fundamental elements-—sup- 
plies of food energy, and supplies of mechanical 
energy. Since at present, partly because of geo- 
graphical conditions, these do not necessarily (or even 
in general) occur together, there is a third essential 
factor, the line of transport. It may be of interest to 
glance, in the cursory manner which is possible upon 
such occasions, at some geographical points concern- 
ing each of these factors, and to hazard some specula- 
tions as to the probable course of events in the 
future. 
In his presidential address to the British Associa- 
tion at its meeting at Bristol in 1898, Sir William 
Crookes gave some valuable estimates of the world’s 
supply of wheat, which, as he pointed out, is “the 
most sustaining food-grain of the great Caucasian 
race.” Founding upon these estimates, he made a 
forecast of the relations between the probable rates of 
increase of supply and demand, and concluded that 
“Should all the wheat-growing countries add to their 
(producing) area to the utmost capacity, on the most 
careful calculation the yield would give us only an 
addition of some 100,000,000 acres, supplying, at the 
average world-yield of 12°7 bushels to the acre, 
1,270,000,000 bushels, just enough to supply the 
increase of population among bread-eaters till the year 
1931." The president then added, “Thirty years is 
but a day in the life of a nation. Those present 
who may attend the meeting of the British Associa- 
tion thirty years hence will judge how far my fore- 
casts are justified.” 
Half the allotted span has now elapsed, and it may 
be useful to inquire how things are going. For- 
tunately this can be easily done, up to a certain point 
at any rate, by reference to a paper published recently 
by Dr. J. F. Unstead (Geographical Journal, August, 
1913), in which comparisons are given for the decades 
1881-90, 1891-1900, and 1901-10. Dr. Unstead shows 
that the total wheat harvest for the world may be 
estimated at 2258 million bushels for the first of these 
periods, 2575 million for the second, and 3233 million 
for the third, increases of 14 per cent. and 25 per 
cent. respectively. He points out that the increases 
were due “mainly to an increased acreage,” the areas 
being 192, 211, and 242 million acres, but also “to 
some extent (about 8 per cent.) to an increased aver- 
age yield per acre, for while in the first two periods 
this was 12 bushels, in the third period it rose to 
13 bushels per acre.” 
If we take the period 1891-1900, as nearly corre- 
sponding to Sir William Crookes’s initial date, we 
find that the succeeding period shows an increase of 
658 million bushels, or about half the estimated 
increase required by 1931, and that attained chiefly by 
“increased acreage.”’ 
But signs are not wanting that increase in this 
way will not go on indefinitely. We note (also from 
Dr. Unstead’s paper) that in the two later periods 
the percentage of total wheat produced which was 
exported from the United States fell from 32 to 109, 
the yield per acre showing an increase meanwhile to 
14 bushels. In the Russian Empire the percentage 
fell from 26 to 23, and only in the youngest of the 
new countries—Canada, Australia, the Argentine—do 
we find large proportional increases. Again, it is 
is constantly expanding and who foresees that his | significant that in the United Kingdom, which is, 
NO. 2292, VOL. 92] 
