The Best and Worst of Times.

The automobile assembly line, new atomic theories, Einstein's general theory of relativity, advances in radio technology, and continuing developments in the social sciences are among the many scientific and technological advances of the 1910s. Modern science was in full bloom. New inventions made life less arduous and more comfortable for millions of urban and rural Americans. Many new products found their way into homes, factories, farms, and hospitals. The decade, however, also bore witness to the devastation of World War I. From 1914 to 1918 the Great War showed that technological advancements, so wondrous in peacetime, could have horrible consequences in war. The first extensive use of submarines in sea battle, the invention of the tank, and the gruesome toll of the machine gun each played its part in the maiming and killing of millions. World War I showed that the achievements of the...