History

SUNDIAL HISTORY

The sundial was humanity’s first technology for precisely marking the passage of time. Not only have sundials achieved this practical goal, but their replication of the heavens has also provided aesthetic and even spiritual satisfaction. This is not easy to comprehend nowadays, since most sundials have become little more than garden ornaments and are not usually very accurate -- even though it is relatively easy to construct an accurate sundial.

Before the first sundials were built, the sun itself was used as a clock. This method would be of little use in today’s world for getting to your dental appointment at just the right time. In the ancient world, however, it was good enough.

The history of sundials begins with simple sticks stuck in the ground. The resulting shadow was used as a rough but reliable means to tell the time. There is no way to know how long this method might have been employed, but it certainly stretches back into the very distant past. Whether this crude technology really deserves to be called a sundial is open to interpretation.

THE ANCIENT WORLD

The real history of sundials begins with the Egyptians, for whom the sun was central to life itself. It’s not surprising that the same civilization that invented the solar calendar would also give us the sundial. Cities and trade had been firmly established, so the need for more precision in telling time had arrived. A piece of a sundial that calibrated the location of the gnomon’s shadow is dated to about 1500 B.C., during the reign of Thutmose III. In order to differentiate between the morning hours and afternoon hours, the position of this T-shaped sundial had to be reversed 180 degrees at noon. A big step in sundial design was taken when the first round sundials that more closely resemble ours appeared in Egypt in about 1300 B.C.

The Babylonians, who were renowned astronomers, built and used sundials soon after the Egyptians, so the sundial of Ahaz may have been of either Egyptian or Babylonian design. Their treatises on sundials were the definitive statements on the subject for over a millennium, right up until the Christian era. The sundial of Ahaz is mentioned in the Old Testament (Isaiah 38:8) and dates from around 730 B.C. This is the oldest known written reference to a sundial.

THE GREEKS AND ROMANS

The Greeks and Romans also used sundials extensively. The indicator on the sundial that casts the shadow is still known by the Greek word "gnomon," which means pointer. The use of towers and obelisks as gnomons to cast shadows indicating the hours of the day was very evident in ancient Greece and Rome. Sundials were found in houses, tombs, temples, baths and other public places.

Not everyone was happy about the prevalence of sundials in ancient Greece, as the following quote shows:

"The gods confound the man who first found out how to distinguish hours. Confound him, too! Who in this place set up a sundial to cut and hack my days so wretchedly Into small pieces! When I was a boy, my belly was my sundial - one more sure, truer, and more exact than any of them. This dial told me when 'twas proper time to go to dinner, when I had ought to eat. But nowadays, why even when I have, I can't fall to unless the sun gives me leave. The town's so full of these confounded dials, the greatest part of its inhabitants, shrunk up with hunger, creep along the streets." Attributed to Plautus, this is one of the oldest known quote on the subject of sundials.

OTHER LANDS AND CIVILIZATIONS

It is well established that sundials were used in China going back to the distant past, but much less is known about the details of this history. After the refinements of the Greeks and Romans, it was the Arabs who were renowned for more complicated sundials of greater accuracy and scope of design. On the other side of the Atlantic Ocean, the advanced civilizations of the Americas also built and used sundials of various designs. Although the Mayan calendar is dramatically different than the 12-month solar calendar employed by the modern world, they did make and use sundials to tell time during the day. While the Inca did employ sundials high in the Andes, it is generally thought that their use was restricted to the priests and the ruling class. The famous Aztec “calendar stone” was primarily used to mark the transit of the earth through its annual trip around the sun. However, it also incorporated eight equidistant holes in its face. Depending upon the time of year, a horizontal stick could be placed in one of the holes to serve as a gnomon, thus allowing the calendar to also be used as a sundial.

THE RENAISSANCE AND THE CLOCK

During the Renaissance, people still used sundials, sometimes small pocket-sized ones, to determine the time of day. But a new way of telling time was arriving on the scene, too. Clocks were invented during the centuries of the Renaissance. They were not invented all at once, but rather developed slowly over the years. Clocks were more of a curiosity at first; most people still used their sundials, or just estimated the time of day by the height of the sun in the sky. In 1777, when the French general Lafayette wanted to express his respect and admiration for his ally and friend General George Washington during the American revolution, he chose a silver Explorer dial as his gift. By the 18th century, clocks and watches began to supersede sundials. They had one big advantage - they worked, 24 hours a day, whether the skies were clear or cloudy. However, they were often unreliable and sundials were depended upon to set the true time.

THE COMING OF THE TRAIN

In earlier days, because of the earth's rotation, the town 20 or 30 miles to the east or west of you would have its clock set slightly differently. Your noon arrived somewhat before that of your Western neighbor but sometime after that of your Eastern one. This was of little consequence to the residents who might never in their lives venture to any of their neighboring towns. Why would it matter if their clocks were five or ten minutes different?

By the late 19th Century, however, time discrepancies began to matter. The reason? The railroads. They demanded schedules. Schedules demanded times; but whose time? Along a hundred mile stretch there might be 6 different cities with 6 different town clocks each different from the other. Passengers needed to know what time the train would depart and when it would reach its destination. Railroaders needed to know when to send the next train in order to avoid serious accidents. In 1884, a conference was held and an agreement was reached to divide the USA into 4 zones each 15 degrees wide - Eastern, Central, Mountain and Pacific. All stations in the zone would carry the same time. In fact, train time, which was kept quite strictly by the railroads, became the standard by which cities and citizens set their clocks. The train whistle became the signal for setting clocks, and sundials now began to steadily disappear from almost everywhere except the garden -- and a few isolated spots on the planet, like Tibet.