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the behavior of plants in breeding, they began to uncover the 
laws of heredity; and as knowledge of these laws increased, it 
became evident that this knowledge could be applied to the prac- 
tical handling of plants, and what we call our revolution in agri- 
culture followed. It is a far cry from a speculation about evolu- 
tion to the solution of our food problem, but the continuity is 
unbroken. It is by such essential and generally unrecognized 
service that scientific research is contributing to human welfare. 
I wish to be more specific, and to indicate some of the ways in 
which science has solved this food problem. 
Through scientific work in the study of heredity, we have 
learned to multiply the races of our useful plants so that they may 
fit in more exactly to the variable conditions in which plants must 
be grown. It is a curious fact that we have been blind so long 
to the teaching of nature that conditions for plants are not the 
same everywhere. We have always realized that the natural 
vegetation of this country is not a monotonous covering. Every 
change in vegetation indicates a special set of conditions for plant 
growth, and yet we have been trying to grow the same races of 
plants everywhere. The result has been that we have gotten 
maximum returns from some areas, minimum returns from 
others, and medium returns from the rest. Our total result has 
been an average. By multiplying races of plants to fit conditions 
more closely, our total result will not be an average, but a mavi- 
mum everywhere. This-one suggestion of science will double 
our production. 
One of the most destructive enemies of our crops is drought. 
On an average our production is cut in half by this enemy. 
Scientific investigation has shown that it is possible to develop 
drought-resistant races of all our useful plants. This means the 
possibility, not only of insuring our crops against drought where 
they are now cultivated, but also of increasing enormously the 
area of cultivation, by adding the so-called arid regions of per- 
petual drought. 
Another destructive enemy of our valuable crops is disease, 
The government has expended millions of dollars in the study of ' 
plant diseases, in the hope of reducing the loss. The scientific 
work of recent years has shown that it is possible to breed disease- 
