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great problem is, how to obtain from the soil its hidden wealth 
with which to meet the present needs of the world, how the 
producer may increase needed food supplies with a reasonable 
profit in so doing, while the consumer may obtain them at a 
moderate cost 
The best scientific authorities in many nations are now giving 
the most exhaustive thought, study and work to the problems 
of the soil. That the soil contains plant food in sufficient 
quantity to meet the increasing needs of the world for ages to 
come there is no question of doubt, but conditions now are such 
that to meet them requires greater and more varied knowledge 
than in the past. 
uch is known about the origin of soils, about the rocks from 
which soils have been made, about the life of the many ages of 
time that is stored up in every atom of soil for present and 
future needs, but about the nutrition of plants and how they , 
appropriate and utilize food, there is much mystery of which the 
highest scientific authorities admit they know as yet but little. 
The United States expends annually about $125,000,000 for 
commercial fertilizers. It is known that practically one third 
of this expenditure is lost, or from which no results are obtained 
in an increase of crops. The value of the animal manure an- 
nually produced in the United States is ane to be $2,800,- 
000,000. It is estimated that through waste sixty per cent. of 
this value, or $1,500,000,000, is lost and fails to produce increase 
in crops. 
R t ific i igati d research are making discov- 
eries that there are substances in the soil in the form of acid com- 
pounds that exert influences upon the soil and upon the constit- 
uents in fertilizers that are responsible for their failure to produce 
increased yield. any gardeners and farmers, as also experiment 
stations, have discovered that in many instances the increase 
in yield of crops has not paid the cost of the fertilizers applied, 
and many farmers have condemned their use. This has given 
rise to further investigation of soil eeadiiens as also to the 
processes by which plants appropriate food substances. 
It was not until the close of the last century that the chemistry 
