OcrosER 2, 1913] 
NATURE 
153 
supply, and for that and other reasons it is therefore 
impossible even to guess at the time which must 
elapse before a universal dearth of coal becomes im- 
minent; it is perhaps sufficient to observe that to the 
best of our knowledge and belief one of the world’s 
largest groups of coalfields (our own) is not likely 
to last three centuries in all. 
Here again the present interest lies rather in the 
phases of change which are actually with us. During 
the first stages of the manufacturing period energy 
in any form was exceedingly difficult to transport, and 
this led to intense concentration. Coal was taken 
from the most accessible coalfield and used, as far as 
possible, on the spot. It was chiefly converted into 
mechanical energy by means of the steam-engine, an 
extremely wasteful apparatus in small units, and 
hence still further concentration; thus the steam- 
engine is responsible in part for the factory system 
in its worst aspect. The less accessible coalfields were 
neglected. Also, the only other really available source 
of energy—water-power—remained unused, because 
the difficulties in the way of utilising movements of 
large quantities of water through small vertical dis- 
tances (as in tidal movements) are enormous; the only 
easily applied source occurs where comparatively small 
quantities of water fall through considerable vertical 
distances, as in the case of waterfalls. But, arising 
from the geographical conditions, waterfalls (with rare 
exceptions such as Niagara) occur in the “ torrential” 
part of the typical river-course, perhaps far from the 
sea, almost certainly in a region too broken in surface 
to allow of easy communication or even of industrial 
settlement of any kind. 
However accessible a coalfield may be to begin 
with, it sooner or later becomes inaccessible in another 
way, as the coal near the surface is exhausted and the 
workings get deeper. No doubt the evil day is post- 
poned for a time by improvements in methods of 
mining—a sort of intensive cultivation—but as we can 
put nothing back the end must be the same, and 
successful competition with more remote but more 
superficial deposits becomes impossible. And every 
improvement in land transport favours the geo- 
graphically less accessible coalfield. 
From this point of view it is impossible to over- 
estimate the importance of what is to all intents and 
purposes a new departure of the same order of 
magnitude as the discovery of the art of smelting iron 
with coal, or the invention of the steam-engine, or of 
the steam-locomotive. I mean the conversion of 
energy into electricity, and its transmission in that 
form (at small cost and with small loss) through 
great distances. First we have the immediately in- 
creased availability of the great sources of cheap 
power in waterfalls. The energy may be transmitted 
through comparatively small distances and converted 
into heat in the electric furnace, making it possible 
to smelt economically the most refractory ores, as 
those of aluminium, and converting such unlikely 
places as the coast of Norway or the West High- 
lands of Scotland into manufacturing districts. Or it 
may be transmitted through greater distances to 
regions producing quantities of raw materials, dis- 
tributed there widespread to manufacturing centres, 
and reconverted into mechanical energy. The Plain 
of Lombardy produces raw materials in abundance, 
but Italy has no coal supply. The waterfalls of the 
Alps yield much energy, and this transmitted in the 
form of electricity, in some cases for great distances, 
is converting northern Italy into one of the world’s 
great industrial regions. Chisholm gives an estimate 
of a possible supply of power amounting to 3,000,000 
horse-power, and says that of this about one-tenth was 
already being utilised in the year 1900. 
NO. 2292, VOL. 92| 
But assuming again, with Sir William Ramsay, 
that coal must continue to be the chief source of energy, 
it is clear that the question of accessibility now wears 
an entirely different aspect. It is not altogether 
beyond reason to imagine that the necessity for 
mining, as such, might entirely disappear, the coal 
being burnt in situ and energy converted directly into 
electricity. In this way some coalfields might con- 
ceivably be exhausted to their last pound without 
serious increase in the cost of getting. But for the 
present it is enough to note that, however inaccessible 
any coalfield may be from supplies of raw material, it 
is only necessary to establish generating stations at 
the pit’s mouth and transport the energy to where it 
can be used. One may imagine, for example, vast 
manufactures carried on in what are now the im- 
mense agricultural regions of China, worked by 
power supplied from the great coal deposits of 
Shan-si. 
There is, however, another peculiarity of electrical 
power which will exercise increasing influence upon 
the geographical distribution of industries. The small 
electric motor is a much more efficient apparatus than 
the small steam-engine. We are, accordingly, already 
becoming familiar with the great factory in which, 
instead of all tools being huddled together to save 
loss through shafting and belting, and all kept run- 
ning all the time, whether busy or not (because the 
main engine must be run), each tool stands by itself 
and is worked by its own motor, and that only when 
it is wanted. Another of the causes of concentration 
of manufacturing industry is therefore reduced in 
importance. We may expect to see the effects of this 
becoming more and more marked as time goes on, 
and other forces working towards uniform distribu- 
tion make themselves more felt. 
The points to be emphasised so far, then, are, first, 
that the time when the available areas whence food 
supply as represented by wheat is derived are likely 
to be taxed to their full capacity within a period of 
about the same length as that during which the 
modern colonial system has been developing in the 
past; secondly, that cheap supplies of energy may 
continue for a longer time, although eventually they 
must greatly diminish; and, thirdly, there must begin 
in the near future a great equalisation in the distribu- 
tion of population. This equalisation must arise from 
a number of causes. More intensive cultivation will 
increase the amount of labour required in agriculture, 
and there will be less difference in the cost of pro- 
duction and yield due to differences of soil and 
climate. Manufacturing industries will be more 
uniformly distributed, because energy, obtained from 
a larger number of sources in the less accessible 
places, will be distributed over an increased number 
of centres. The distinction between agricultural and 
industrial regions will tend to become less and less 
clearly marked, and will eventually almost disappear 
in many parts of the world. ; 
The effect of this upon the third element is of first- 
rate importance. It is clear that as the process of 
equalisation goes on the relative amount of long- 
distance transport will diminish, for each district will 
tend more and more to produce its own supply of 
staple food and carry on its own principal manufac- 
tures. This result will naturally be most marked in 
what we may call the ‘‘east-and-west”’ transport, for 
as climatic controls primarily follow the parallels of 
latitude, the great quantitative trade, the flow of food- 
stuffs and manufactured articles to and fro between 
peoples of like habits and modes of life, runs primarily 
east and west. Thus the transcontinental functions 
of the great North American and Eurasian railways, 
the east-and-west systems of the inland waterways of 
