There was a period when how many minutes were left on a cell phone didn't matter. Nor was the difference between a gold and silver medal calculated in 1/100ths of a second. It was the earliest measure of time: the apparent movement of the sun, moon, and stars across the sky determining how long the day was and what season it was. These men and women who looked to the sky provided the impetus for priests, astrologers, and nobles to refine the measurement of time beyond "it's morning" or "it's toward night". Most scholars believe we owe our time basics to the Sumerians, but since there are only a couple of clay tables remaining from their culture, credit is given to the Babylonians who left records. The culture between the Tigris and Euphrates rivers, on which modern Baghdad is built, had a number system call sexagesimal, that is, based on 60. They devised a year of 360 days and divided the hours into 60 minutes and those minutes into 60 seconds. There were some attempts, mainly in Europe, in the 18th century to introduce a decimal clock and calendar ( based on 10, familiar to Europe with meters, grams, and liters ) but they never caught on. It was the Egyptians, inventing the precursor of the sundial with an obelisk about the same time as the Babylonian Empire reigned in the Middle East, who determined that there were 12 of those 60-minute hours to daylight and 12 of them to night. We live today in the 21st century with these divisions of time devised over 3,500 years ago.



The progress of the sundial in Egypt refined the estimates of the Babylonians to a 365-day year, mainly based on the appearance of Sirius next to the sun at the annual flooding of the Nile. This adjustment to the 360 days of the Babylonian calendar led to a more accurate measurement of the length of the day and it's hours over the years. The traditional sundial continues in use even today, though mostly decorative now, but it's accuracy when properly aligned for latitude is uncanny.



Experiments with "time-keeping devices" such as sand and water were developed over the next thousand years, each of them compared for accuracy next to a sundial, much as today we have standard clocks against which to compare the accuracy of our manufactured clocks. The egg timer is, perhaps, the most used current timekeeper that goes back to the time of the construction of the pyramids. Much was made by Greek philosophers comparing life with the sand glass, the upper part the future and the lower part the past with life happening grain of sand by grain of sand in the present. While those ancient sandglasses were either one or two hour sandglasses, usually measuring work time before breaks for bread and water for slaves, our 3-minute egg timer uses the same principle: sand flows from the full container to the empty at a predictable and measurable rate.



That same principle was used in the water clock, that water would flow from a filled container through a measured aperture, into an empty container at a predictable rate, calibrated by comparison with a sundial, and could be used for the measurement of longer periods of time than the sandglass. One interesting historical note, attributed to Plato without any verification, is the "invention" of the alarm clock. It is reported that Plato placed a float with brass balls on it in the lower chamber of a water clock, and when the water reached the top, there was an opening for the water and the balls to fall on a brass plate. The clatter of the balls would wake his students so they would not be late for classes!



With the fall of the Roman Empire in the fourth century, there was almost no technological advance throughout the Western world for nearly 600 years: which we now call the Dark Ages. The sundial remained, with sand and water clocks, the measurement of hours and days. There were even portable sundials, carried almost like watches by nobles and shipping workers dependent of the right hour for the tides. It was not until the early part of the 13th century that advances were made in the measurement of time with the invention of mechanical clocks. The first of these clocks appear in historical records as clocks in church towers or town halls. Indeed, the word "clock" comes from Medieval Latin, "cloca" meaning "bell" as the closely regulated prayer times in churches and monasteries were signaled by the striking of a bell. There is very little information on the predecessors of these clocks, although there certainly must have been experiments and research. The very earliest of these clocks simply rang bells, probably those already existing in the towers, to strike the hour. Later, a stationary hand was added and the clock face actually rotated by the hour. As the years progressed, minutes were added and the advent of floor clocks with mechanical movement appeared in castles and houses of nobility in Europe and England toward the middle of the 15th century.



An interesting aside on these clocks is the use of the Roman Numeral IIII rather than IV for the number "4". It was a carry over from the Roman sundial to the clock face, in which IIII was used for two main reasons. First, in Latin, IVPITER is the way the name Jupiter is written, the chief god of ancient Rome; hence, it was though inappropriate to use that abbreviation IV on a sundial. And, secondly, the penchant for Roman math was to use addition rather than subtraction, and IV represents subtracting "1" from "5". So into our time, any clocks made or reproductions made of antique clocks have IIII for the number "4".



The main revolution in time measurement came in 1656 when Christian Huygens in Holland invented the pendulum for regulating clock movements. More will be discussed about the pendulum in the article "Clock Movements" on this website, suffice it to say here that this technology spread rapidly throughout Europe and by the end of the 17th century, virtually all clocks were made with either a spring movement or weights as their power source, with either a balance wheel in the case of a spring movement or a pendulum in the case of weights to regulate accuracy. While originally using four wheels with reduction cams, very rapidly other wheels were added to power the display of months, phases of the moon, astrological signs, and almost anything else the clock maker could think of, including simply decorative movements such as a ship moving up and down on painted water. Until the advent of electricity and batteries in what we may call "modern times", the variety of clocks made in Europe, England, America, and the Orient used the same mechanics to measure our time.