Michael Downing is obsessed with Daylight Saving, the loopy idea that became the most persistent political controversy in American history. Almost one hundred years after Congressmen and lawmakers in every state first debated, ridiculed, and then passionately embraced the possibility of saving an hour of daylight, no one can say for sure why we are required by law to change our clocks twice a year. Who first proposed the scheme? The most authoritative...