Modernizing the Farm.

In 1910 more than a fifth of the nation's population worked on farms, and farming remained the nation's leading business. Farm yields grew in the decade by leaps and bounds, largely because of, as Secretary of Agriculture James Wilson recognized, "the application of scientific methods in all branches of farming." The farmer with hoe and scythe had been transformed in many regions into the farmer with a harvester.

Fertilizers.

The use of chemical fertilizers had doubled between 1900 and 1910, and during the 1910s the growth of the fertilizer industry continued unabated. One of the greatest achievements in the history of chemistry—judged from the practical perspective of its utility for the population at large—was the invention by German scientists of a process for "fixing" atmospheric nitrogen into chemical fertilizers. Used in the United States and around the world, the new process made...