The Tribune - Spectrum



Sunday, January 30, 2000
Article

Measuring time that ticks by
By Mohinder Singh

Time has no divisions to mark its passage, there is never a thunderstorm or blare of trumpets to announce the beginning of a new month or year. Even when a new century begins it is only we mortals who ring bells and fire off pistols.

— Thomas Mann in The Magic Mountain (1924)

A NEW millennium — courtesy Gregorian Calendar — has just been rung in with fantastic fanfare. And rung in all over the globe at midnight hour — courtesy Greenwich Mean Time. The earth itself went through the millennium change without a whimper.

The importance of measuring time was realised right from early times. And so began mankind’s unending quest to measure time with increasing precision. Indeed David S. Landes in his notable book The Wealth and Poverty of Nations ascribes Western lead in clock-making as a crucial factor favouring European advances in navigation, exploration, and consequent empire building — clocks proving as potent as naval guns in overseas conquests. The British were in the 18th century the world’s leading producers and consumers of timekeepers.

  The first time-measuring devices were sundials. These had the disadvantage of not functioning at night or on cloudy days, and since the length of the day varied everywhere, sundial time varied everywhere, too.

Then came water clocks. These kept time by measuring water as it dropped from a hole in the bottom of a bowl. But water emptied faster when the bowl was full and pressure greater.

By the Middle Ages, it was the turn of the hourglass; sand run through a hole. As the weight of sand was a drawback, the hourglass was mostly used for measuring small units of time. It was especially used in determining the speed of a ship. A seaman tossed a rope with knots tied at measured intervals. Another crewman monitored a sandglass that measured 28 seconds. If 5 knots slipped through the seaman’s hand in 28 seconds, the ship was moving at 5 "knots" per hour — one nautical knot equals 1.15 miles.

First mechanical clocks were ringing in Europe around 1300; the word "clock" derives from the German Glocke, or "bell". These clocks gave time by sounding bells, they had no faces or hour or minute hands. And were powered by descending weights, and progressively by a coiled spring.

The development of pendulum (a device that swings at a constant rate) gave clocks much greater accuracy; the longer the pendulum, the greater the accuracy.

But pendulum clocks were no good at sea; the motion of the ship altered the swing. And ships needed accurate time very badly. While finding latitude was relatively easy, finding longitude called for accurate time. If a sailor knew the time of home port and the time aboard the ship, he could calculate his longitude (15 degrees for every hour). Aided by latitude/longitude maps, the ship’s position can be easily determined.

As thousands of lives were lost on sea with ships getting hopelessly lost, the British Parliament passed the Longitude Act of 1714, offering £ 20,000 (around £ 10 million today) to anyone who could determine longitude at sea.

One John Harrison, a carpenter’s son with no formal education, eventually succeeded after forty years of toil. In 1759, he finally produced a 5-inch diameter clock that spent 81 days at sea on a test voyage, and lost a mere 5 seconds. There’s now a bestseeller Longitude by Dava Sobel.

And soon a film on Harrison, making his clocks. Incidentally, the committee set up to release the award, dillydallied a lot in doing so, till the King himself intervened on behalf of Harrison.

Harrison’s watch, they say, was the technological triumph that paved the way for the British Empire.

Later, the interchangeability of parts made mass production of clocks possible. Yet most towns kept their own time, setting their clocks and watches by the sun. This created terrible complications, especially in the running of trains. Great Britain solved the problem at the country level by fixing what it called Greenwich Mean Time — a legendary meridian passing through Greenwich.

Soon every country followed suit, fixing one time or more as its Mean Time. Later a 25-nation Congress in Washington in 1884 endorsed Greenwich as zero degree longitude. France, wanting the line to pass through Paris, abstained. Modern communications, particularly international aviation, wouldn’t just function without the world observing one standard time.

Wearing a wristwatch is now a routine; indeed many of us would feel lost without one. Yet wristwatches were a rarity before World War. A few fashionable ladies did wear ornamental watches on their wrists, but "real" men only sported pocket watches. However, in the War it wasn’t easy for a soldier to extricate a pocket watch, with one hand holding a rifle and the other a grenade. Ultimately wristwatches became a standard issue for troops. And soon the idea caught on with the general public.

While watch and clock manufacturers concentrated on the products’ appearance and marketing, scientists effected a breakthrough in time-keeping. A small amount of electrical current was used to vibrate quartz crystals. These vibrations then electronically translated into time with a small battery as power source. Soon quartz and digital watches became the rage.

But scientists persist in their search for greater and greater precision in measuring time. This search took a quantum leap forward with the discovery that oscillations of cesium-133 atoms can be manipulated to allow a time calculation with an error of one second every 1.4 million years. And cesium vibrations, unlike that of quartz, are not influenced by age and temperature.

And now a move is afoot to make an atomic clock that would just lose one second in 313 million years. There is the project to put such a clock aboard the International Space Station in 2004. It seems that once you get interested in time, it doesn’t let you go. Some call it a disease. Terms like "hurry sickness", "acceleration disorder", "compression tiredness" have entered general conversation. Yet time can also be a marvellous obsession.

India as a country was noted for its sundials. But we came rather late to mechanical timekeepers. We had gifted jewellers who could do wondrous things with precious metals, and craftsmen who could turn out some of the best guns of that era, but we failed to make clocks and watches. Evidently, we didn’t display such a passionate interest in knowing the time as the Europeans.

As late as 1786, Colonel Claude Martin, a Frenchman who rendered distinguished service in India, complains about the complete absence of locally-made clocks and watches. He had to procure one for himself from Europe. And he often sold European watches to Indian nobles. We, like the Chinese, were not doing anything in that area.

Since then we have become far more time conscious. Still a good strategy would be to make wristwatches cheaper and encourage more and more people to wear them. For example, a wristwatch could be made a standard item of uniform for various employees. Greater consciousness of time, in general, leads to greater productivity.

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