The production of nitrogen for plant food in peace and explosives in war is more and more important. It is one of the chief sustaining elements of life. It is estimated that soil exhaustion each year is represented by about 9,000,000 tons and replenishment by 5,450,000 tons.
 Calvin Coolidge, State of the Union Address (3 December 1924). copy citation

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Author Calvin Coolidge
Source State of the Union Address
Topic exhaustion food
Date 3 December 1924
Language English
Reference
Note
Weblink http://www.gutenberg.org/files/5036/5036-h/5036-h.htm

Context

“In time for action at this session, I hope to report to the Congress such legislative remedies as the conference may recommend. An appropriation should be made to defray their necessary expenses.
MUSCLE SHOALS
The production of nitrogen for plant food in peace and explosives in war is more and more important. It is one of the chief sustaining elements of life. It is estimated that soil exhaustion each year is represented by about 9,000,000 tons and replenishment by 5,450,000 tons. The deficit of 3,550,000 tons is reported to represent the impairment of 118,000,000 acres of farm lands each year.
To meet these necessities the Government has been developing a water power project at Muscle Shoals to be equipped to produce nitrogen for explosives and fertilizer.” source