152 
NATURE 
and always has been, the most sensitive of all wheat- 
producing countries to variations in the floating 
supply, the rate of falling-off of home production 
shows marked if irregular diminution. 
Looking at it in another way, we find (still from 
Dr. Unstead’s figures) that the total amount sent 
out by the great exporting countries averaged, in 1881- 
90, 295 million bushels, 1891-1900, 402 millions, 1901-10, 
532 millions. These quantities represent respectively 
130, 15°6, and 16'r per cent. of the total production, 
and it would appear that the percentage available for 
export from these regions is, for the time at least, 
approaching its limit, i.e. that only about one-sixth 
of the wheat produced is available from surpluses in 
the regions of production for making good deficiencies 
elsewhere. 
There is, on the other hand, abundant evidence 
that improved agriculture is beginning to raise the 
yield per acre over a large part of the producing area. 
Between the periods 1881-go and 1901-10 the average 
in the United States rose from 12 to 14 bushels; in 
Russia from 8 to 10; in Australia from 8 to 10. It 
is likely that, in these last two cases at least, a part 
of the increase is due merely to more active occupa- 
tion of fresh lands as well as to use of more suitable 
varieties of seed, and the effect of improvements in 
methods of cultivation alone is more apparent in the 
older countries. During the same period the average 
yield increased in the United Kingdom from 28 to 
32 bushels, in France from 17 to 20, Holland 27 to 33, 
Belgium 30 to 35, and it is most marked in the 
German Empire, for which the figures are 19 and 29. 
In another important paper (Geographical Journal, 
April and May, 1912) Dr. Unstead has shown that 
the production of wheat in North America may still, 
in all likelihood, be very largely increased by merely 
increasing the area under cultivation, and the reason- 
ing by which he justifies this conclusion certainly holds 
good over large districts elsewhere. It is of course 
impossible, in the present crude state of our know- 
ledge of our own planet, to form any accurate esti- 
mate of the area which may, by the use of suitable 
seeds or otherwise, become available for extensive 
cultivation. But I think it is clear that the available 
proportion of the total supply from ‘‘ extensive” 
sources has reached, or almost reached, its maximum, 
and that we must depend more and more upon inten- 
sive farming, with its greater demands fer labour. 
The average total area under wheat is ex ‘mated by 
Dr. Unstead as 192 million acres for 1881-90, 211 
million acres for 1891-1900, and 242 million acres 
for 1901-10. Making the guess, for we can make 
nothing better, that this area may be increased to 
300 million acres, and that under ordinary agriculture 
the average yield may eventually be increased to 
20 bushels over the whole, we get an average harvest 
of 6000 million bushels of wheat. The average wheat- 
eater consumes, according to Sir William Croolkxes’s 
figures, about four and a half bushels per annum; 
but the amount tends to increase. It is as much 
(according to Dr. Unstead) as six bushels in the 
United Kingdom and eight bushels in France. Let us 
take the British figure, and it appears that on a 
liberal estimate the earth may in the end be able to 
feed permanently tooo million wheat-eaters. If pro- 
phecies based on population statistics are trustworthy, 
the crisis will be upon us before the end of this 
century. After that we must either depend upon some 
substitute to reduce the consumption per head of the | 
staple foodstuff, or we must take to intensive farm- 
ing of the most strenuous sort, absorbing enormous 
quantities of labour and introducing, sooner or later, 
serious difficulties connected with plant-food. We 
leave the possibility of diminishing the rate of increase 
NO. 2292, VOL. 92] 
[OcToBER 2, 1913 
in the number of bread-eaters out of account for the 
moment. 
We gather, then, that the estimates formed in 1898 
are in the main correct, and the wheat problem must 
become one of urgency at no distant date, although 
actual shortage of food is a long way off. What is 
of more immediate significance to the geographer is 
the element of change, of return to earlier conditions, 
which is emerging even at the present time. If we 
admit, as I think we must do, that the days of 
increase of extensive farming on new land are draw- 
ing to a close, then we admit that the assignment of 
special areas for the production of the food-supply of 
other distant areas is also coming to its end. The 
opening up of such areas, in which a_ sparse 
population produces food in quantities largely in 
excess of its own needs, has been the characteristic 
of our time, but it must give place to a more uniform 
distribution of things, tending always to the condi- 
tion of a moderately dense population, more uniformly 
distributed over large areas, capable of providing the 
increased labour necessary for the higher type of 
cultivation, and self-supporting in respect of grain- 
food at least. We observe in passing that the colonial 
system of our time only became possible on the large 
scale with the invention of the steam-locomotive, and 
that the introduction of railway systems in the appro- 
priate regions, and the first tapping of nearly all such 
regions on the globe, has taken less than a century. 
Concentration in special areas of settlement, for- 
merly chiefly effected for military reasons, has in 
modern times been determined more and more by the 
distribution of supplies of energy. The position of 
the manufacturing district is primarily determined by 
the supply of coal. Other forms of energy are, no 
doubt, available, but, as Sir William Ramsay showed 
in his presidential address at the Portsmouth meeting 
in 1911, we must in all probability look to coal as 
being the chief permanent source. 
In the early days of manufacturing industries the 
main difficulties arose from defective land transport. 
The first growth of the industrial system, therefore, 
took place where sea transport was relatively easy; 
raw material produced in a region near a coast was 
carried to a coalfield also near a coast, just as in 
times when military power was chiefly a matter of 
“natural defences,”’ the centre of power and the food- 
producing colony had to be mutually accessible. Hence 
the Atlantic took the place of the Mediterranean, 
Great Britain eventually succeeded Rome, and eastern 
North America became the counterpart of northern 
Africa. It is to this, perhaps more than to anything 
else, that we owe our tremendous start amongst the 
industrial nations, and we observe that we used it to 
provide less favoured nations with the means of 
improving their system of land transport, as well as 
actually to manufacture imported raw material and 
redistribute the products. 
But there is, of course, this difference between the 
supply of foodstuff (or even military power) and 
mechanical energy, that in the case of coal at least 
it is necessary to live entirely upon capital; the storing 
up of energy in new coalfields goes on so slowly in 
comparison with our rate of expenditure that it may 
be altogether neglected. Now in this country we 
began to use coal on a large scale a little more than 
a century ago. Our present yearly consumption is of 
the order of 300 millions of tons, and it is computed 
(General Report of the Royal Commission on Coal 
Supplies, 1906) that at the present rate of increase 
“the whole of our available supply will be exhausted 
in 170 years."" With regard to the rest of the world 
we cannot, from lack. of data, male even the broad 
assumptions that were possible in the case of wheat 
— 
