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Daylight Saving Time

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Daylight saving time starts this week end, as we turn our clocks forward one hour, resulting in giving us more daylight at the end of the day.

My grandmother was a music teacher. She always kept two clocks on her piano. She was a religious woman and said one of the clocks was set to God's time and the other to man's time. The one set on standard time she called God's time, and the one on daylight saving time she called man's time. The family always joked about it, but it was no joking matter to her. The two clocks remained on her piano year around.

Most authorities agree that the world is divided into twenty-four times zones. Prior to the advent of railroads there was no reason for time zones to be standardized, and countries and cities had their own ways of determining what time it was. But with the advent of a single mode of uninterrupted travel, like the railroad that went from country to county in Europe and from one city to another within a single country, including the United States, there was need for a standardized system of time zones throughout the world.

In 1884 delegates from twenty-two nations met in Washington, DC, to agree upon a worldwide time system. The countries selected the longitudinal line that runs through Greenwich, England, as the standard from which they would measure the world's time zones. Using the longitudinal line of Greenwich as the base line, they determined that time would change by one hour for every fifteen-degree change in longitudinal lines, thus creating twenty-four time zones around the world. This entire system of time keeping and time zones is known as Greenwich Mean Time (GMT).

Many countries continued to adhere to their own systems of measuring and setting time. But eventually most major countries, especially those engaged in world trade, found it advantageous to adopt GMT. Several small countries adhere to other systems, many with twenty-five time zones. And two geographically large countries have never used GMT. India originally had two time zones, but since the late 1880's has used only one time zone for the entire country. In 1912, the Republic of China adopted five time zones, none of which was identical with GMT, but in 1949, as the Communist Party consolidated control of the country, Chairman Mao Zedong decreed that, for purposes of national unity, all of China would have the same time.

The continental United States has four times zones. Although they are based on longitudinal lines, time zones are not always in a straight line. They are sometimes determined by how countries' and states' borders are positioned or to adhere to wishes of local people. There are eleven states in the United States that are divided into two time zones.

Having a brief background of times zones and how time is determined from one place to another, let's turn to daylight saving time.

Daylight saving time (DST) is a change in standard time with the purpose of making better use of daylight. DST is used to move an hour of daylight from the morning to the evening. The idea is: by getting up one hour earlier in the morning people will go to bed one hour earlier at night, thus using less electricity to light homes during the dark evening hours. This is accomplished by setting clocks forward one hour. Studies by the U.S. Department of Energy indicate that the savings are small but significant, conserving as much as 10,000 barrels of oil per day.

Historians tell us the general idea for daylight saving time was first written about in 1784 by Benjamin Franklin while in France. He published an essay, "An Economical Project for Diminishing the Cost of Light," that proposed to economize the use of candles, which were expensive, by rising earlier and going to bed earlier. However, most historians contend that modern DST was first proposed in 1895 by George Vernon Hudson, an entomologist from New Zealand, when he put forth the idea of a two-hour shift forward in October and a two-hour shift back in March.

Records indicate that DST was first formally adopted by a country in 1916, when Germany adopted DST during World War I to conserve the use of artificial lighting and thereby save badly needed fuel for its war effort. The idea was picked up by countries on both sides of the war, including the United States. Most countries reverted to standard time following the war, but quickly began using DST again during World War II.

On February 9, 1942, President Franklin D. Roosevelt instituted year-round DST in the United States. The law, however, was not actually enforced until forty days after the bombing of Pearl Harbor. Instead of DST, it was called "War Time." A month after the surrender of Japan in August 1945, the United States returned to standard time.

DST has historically been met with mixed reviews. DST has been more popular with urban dwellers than in rural areas, where people have much less freedom in manipulating the time of day they tend to the needs of plants and animals.

Other than in war years, states have been free to use or not use DST, but the schedule for using DST is determined by the U.S. Congress. That schedule has changed numerous times since World War II. The current schedule, set in 2007, follows the Energy Policy Act of 2005, which calls for DST to start on the second Sunday in March and end on the first Sunday in November. Currently, every state has adopted the use of DST except two: Arizona, where the entire state except the Navajo Nation community is on standard time year around, and Hawaii, also on standard time year around.

Hopefully, you will better appreciate daylight saving time as you "spring forward" and "fall backward."

(Information is from documents published by the U. S. Department of Energy and the Library of Congress.)