Why we spring forward next Sunday

Yes, it's that time again - most of us in the United States will be turning our clocks forward one hour at 2:00 am this coming Sunday. If you're like me, you have some vague ideas about why we practice Daylight Savings Time, but don't really know the facts. I decided to find out what's behind this plan (officially known as the Uniform Time Act) that causes so much muddle-headedness and so many missed appointments twice a year. Most of this information comes from a wonderful Web site at webexhibits.org/daylightsaving by the Institute of Dynamic Education Advancement, provided as a complement to the Official US Time Web site at www.time.gov.

First of all, what is it? Daylight Savings Time is a scheme that originated with Benjamin Franklin in an essay on thrift, where he calculated that if the people of Paris aligned their activities more closely with the sun, 64,050,000 pounds of candle wax would be saved per year. He further proposed that:

A tax be laid on every window built with shutters to keep out the light of the sun.
Candles rationed to one pound per family per week, and the regulation enforced by the constabulary.
Guards posted to stop the passage of all coaches, etc. upon the streets after sunset except those of physicians, surgeons and midwives.
Every morning as soon as the sun shall rise, church bells and, if necessary, cannon shall inform the citizenry of the advent of light and "awaken the sluggards effectually and make them open their eyes to see their true interests ... All the difficulty will be in the first two or three days; after which the reformation will be as natural and easy as the present irregularity. ... Oblige a man to rise at four in the morning, and it is probable he will go willingly to bed at eight in the evening."

After many different permutations over the years, the current US plan was formalized during the oil embargo of the 1970s in an attempt to save energy. In fact, it "trims the entire country's electricity usage by a significant, but small amount, of less than one percent each day," according to studies conducted by the US Dept. of Transportation.

When is it? Math geeks can use the following equations to calculate when DST starts and ends. "The divisions are integer divisions, in which remainders are discarded. 'mod' means the remainder when doing integer division, e.g., 20 mod 7 = 6. That is, 20 divided by 7 is 2 and 6/7th (where six is the remainder). With: y = year, begin DST: Sunday April (2+6*y-y/4) mod 7+1 and end DST: Sunday October (31-(y*5/4+1) mod 7)."

For everyone else, DST begins at 2 am on the first Sunday of April and ends on the last Sunday of October.

Where is it? Approximately 70 countries use some form of Daylight Savings Time, with the only industrialized country not using DST being Japan. The page webexhibits.org/daylightsaving/g.html has a detailed list of countries and their start and end dates. In the US, Arizona, Eastern Indiana, Hawaii, the Pacific Territories, Puerto Rico and the Virgin Islands do not observe DST.

But we certainly do here on San Juan Island, so don't forget to change your clocks!

Lauren Stara
Director, San Juan Island Library
phone number 360.378.2798
e-mail lstara@sjlib.org

news@sanjuanislander.com

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Why we spring forward next Sunday