“Early to bed, and early to rise, makes a man healthy, wealthy and wise.”
SUNDAY, MARCH 10: Set your clocks ahead and get ready to soak up extra sun tonight—Daylight Savings Time begins at 2 a.m. Also termed “summer time” in several countries, DST varies widely by region and local practice. In the United States, Hawai’i and most of Arizona don’t observe DST at all. (This year, new proposals also are addressing DST. Read more here.) Nonetheless, the majority of America will turn its clocks ahead at 2 a.m. today.
WATER CLOCKS AND HORA TERTIA
Modern adaptation of DST stems from a George Vernon Hudson proposal in 1895, but the concept of changing clocks began with ancient civilizations. Roman water clocks measured months of the year with different scales, signaling hours of varying lengths: the third hour from sunrise—known as hora tertia—lasted 44 minutes at winter solstice, and 75 minutes at summer solstice. (Wikipedia has details.) While equal-length hours are the most generally used now, some institutions continue to utilize unequal-length hours, such as in monasteries of Mount Athos and in some Jewish customs.
FROM BEN FRANKLIN TO GEORGE HUDSON
An envoy to France, Benjamin Franklin anonymously published a letter suggesting that Parisians economize on candles by rising earlier; but modern DST was first proposed more than a century later, by New Zealand entomologist George Vernon Hudson. DST first went into action during WWI, after which it was largely abandoned, until WWII. Most countries have continued to use DST since that time.
The pros and cons of DST are largely debated, and it remains unobserved in most of Asia, Africa and countries close to the equator; the United States, Canada, the European Union and Australia remain its strong proponents. Most Muslim countries do not use DST because of its effect on the fasting month of Ramadan.