Once upon a time, there was no time — at least as we reckon it.

All the increments we use to measure time, such as seconds, minutes, hours, days, weeks, months and years, came into being gradually as various civilizations devised ways to organize their lives.

Time, and the way we look at it, changes over time. One of the ways we tinkered with time in the 20th century was the adoption of daylight-saving time — the whole "spring ahead, fall back" thing, when we move our clocks ahead or back an hour, based on the rationale that we save energy by having more daylight at the end of the day.

First adopted in 1967 in the United States, DST kicked in at 2 a.m. on the first Sunday in April. Clocks went back to standard time at 2 a.m. on the last Sunday in October.

Since then, various changes have come along. In 1972, a congressional amendment allowed some areas to be exempt from DST, including Arizona, Hawaii, parts of Indiana, Puerto Rico, the Virgin Islands and American Samoa. There have been times when we stayed on daylight-saving time all year 'round or changed the beginning and ending in other ways. Since 1986, the April/October formula has remained intact — until this year.

Last fall Congress enacted the Energy Policy Act of 2005, which changed the beginning of DST to the second Sunday in March and the end to the first Sunday in November. The secretary of energy is required to track and report the impact of this change, and then Congress will decide whether energy savings are significant enough to keep the new schedule or revert to the old.

In honor of Sunday morning's shift, here are some bits and pieces of history, lore and trivia dealing with the whole idea of time and daylight-saving time, in particular.

All about Franklin's idea

The idea of taking an hour off one end of the day and adding it to the other — daylight-saving time — was first proposed by Benjamin Franklin while he was serving as an American delegate in Paris. In an essay titled "An Economical Project," he discussed the thrift of natural versus artificial lighting and noted that if the Parisians shifted time correctly they could save enormous amounts of tallow and wax used for candles.

Franklin was 78 at the time, and wrote the essay somewhat in jest. But some of his friends, who had invented a new kind of oil lamp, were quite taken with the idea.