Evening star. [volume] (Washington, D.C.) 1854-1972, 1905-01-11
MORE ROOM FOR MEN
CAREFUL T1ILAGE OF LAND WILL
DOUBLE EARTH'S CAPACITY.
Engineering Possibilities of Irrigation
and Drainage in the United
States.


Prof n. S. Shaler of Harvard College in the Inter-
national Quarterly.
The conditions of the lands which are
now open to the increase in population
which has to be expected within two or
three centuries may be taken approximate
ly to show that, at most, there is enough
to admit Of something like a doubling
of the present numbers; that without any
considerable engineering work in lands not
now available for tillase total of about
1900, 100000 can be supported in tolerable
comfort.
The question arises as to the additional
food-gving capacity of the earth which
may be won by means of engineering and
other scientific work, in irrigating arid
fields draining those which are excess
lVely watered. or by improving the methods
OF fertilizing soils now in use.
Desert and Swamp.
1t is impossible with the present lack of
information. to determine accurately how
extensive is the field which may be won to
tillage by the work of the engineer. This
winning from the excessively arid lands
will be done by irrigation, and from the
morasses, the fresh-water swamps and the
marine marshes by drainage. In Europe the
larger part of the land thus winnabie has
long been brought to use; it is not likely
that an increase of 10 per cent in the food
giving capacity of its soils can, by any
known means, be realized. In the less de-
veloped continents the gain is likely to be
much greater
Thus within the limits of the United
States the writer has estimated that the
fields improbable by drainage in the man
ner already applied in Holland would add
to the tillable ground of the country an
area somewhat exceeding 100000 square
miles in extent, with food-giving value
about four times that of the state of Illi-
nois wherein the soil would be far more
enduring than that of any upland district
The Complementary process, that of irriga-
ton, promises to afford yet larger gains
including the area of the south and the
middle west, where the system would
greatly increase the food-giving value of
the soil; we may reckon the possible en-
iargement from it would be even greater
than that afforded by complete drainage
of the morasses. Taking the continent Of
North America as a whole, 1t seems prob
able that the existing capacity of it's soils
for feeding men may be doubled by the
work of the engineer through his skill in
watering and unwatering its deserts and
morasseS.
Other Continents
On the other continents the opportunities
for winning good land from arid deserts
are probably less than in North America,
yet the possible gain is such that we may
reckon that when his great work is done
the engineer will have recovered land
enough to feed the existing population of
the earth. In Africa there is the magnifi-
cent problem of the Nile, a river (which
wastes to the sea in it's annual floods water
enough to fertilize tenfold the desert that
1t now makes fertile There is the valley
of the Twin rivers of Asia, where a realm
once fertile has become waste by the loss
Of its irrigation works. There are in all
the great lands vast areas of lakes,
sws.mps and marshes awaiting the skillful
labor which has won Holland from the
sea. The largest opportunity of profit is in
such brave combats with the incomplete
work of nature
The problem of how we are to maintain
the fertility of the. soil when the earth is
taxed by a population thrice as great as
to restrain the excessive rapidty with
which titled soils pass to the sea and our
ability to restore to the land the materials
which the cultivated plants remove. We
shall find that both these needs are fairly
to be met by the resources of modern sci
ence; the first by proper control of the
movements of water from where 1t falls
upon the land to its station in the ocean,
and the second by resort to the ocean
and the under earth for the materials to
renew the fertility of the ground when 1t is
exhausted by cropping. There Is much to
do in order to make the earth fit to bear
the life to come, but there is every reason
to believe that our science Is ready for the