How many times have you wondered, "What time is it?" and turned to your wrist only to find you forgot to put on your watch. We have become so programmed to know what time it is and schedule our lives around it that it is second nature to bend your arm, turn your wrist and get the answer. It has not always been so easy, or even necessary as you will see by looking back to a time before clocks and watches.

Like Night and Day

The precision with which we measure time today is light years away from how it was done, not so long ago. Time was once measured completely by the universe around us - and still is in a sense when you understand the science and physics behind the measurement of time and what makes a clock work (more on this in part 2). What earlier civilizations knew and relied upon each day was that the sun came up and went down and that block of time became a day. To measure greater expanses, the moon and its reliable cycles were also observed. The moon was used to measure the time period which came to be known as a month - more technically a lunar month of 28 days - or the time it took for the moon to go from new to crescent to full and new again.

Ancient Civilization

Even more than just observing the moon, sun, and planets, there are artifacts that show us that time was measured a bit more precisely. Early calendars and "clocks" were found in what is now Iraq, once the dwelling place of the ancient Sumerians, and consisted of a calendar that was divided into 30 day segments according to the cycle of the moon. It was then divided into 12 sections which corresponded to 2 hours of today's time. Further, the calendar was sectioned off into 30 more parts equivalent to 4 modern-day minutes.

Stonehenge is located in England and was built more than 4,000 years ago. Not much is completely understood about this mysterious structure, but the way it is positioned has scientists believing that it somehow was used to record seasons and the phenomenon of lunar eclipses and the like.

Sundials

The Sumerian culture passed away without the information about their timekeeping being discovered until more modern times. The next phase of more precise time measurement was used by the Egyptians. They created the Obelisk around 3500 BC which looked like today's Washington Monument, well-known to visitors of the Nation's capital. This tall, tapered monument would cast shadows throughout the day, but was primitive still in how closely the time periods could be measured. It mostly reflected a change between morning and afternoon, and how the days would get shorter or longer with the seasons.

The sundial on the other hand was first used about 1500 BC and was a much smaller and more portable timekeeping device. It was divided into 10 equal parts with two additional segments representing twilight and dawn. The sundial itself then emerged from a horizontal plate to a bowl shape with pointer and inscribed lines to mark off the hours. It is believed that by 30 BC there were more than 13 different styles of sundials used in the evolving societies of Asia Minor, Italy, and Greece.

When one thinks about the precision of a finely crafted Swiss timepiece it is hard to imagine a time when time was so ambiguous. Could society function without time measurements to the very minute? Perhaps in another millennium society will wonder how we functioned living in just one time.

This is the first of a series of articles on the evolution of time measuring and how timepieces come to become what they are today.