Horology—the science that involves the making of machines that indicate time—is among the oldest of the scientific crafts. The “heart” of these machines is the escapement. This regulates the rate at which the power driving the machine is released. When this power is allowed to escape only in small amounts and at regular intervals, periods of time can be measured. No one knows exactly when the first all-mechanical clock was invented, but a milestone was reached about the year 1500, when portable timepieces were first made.
The now common wristwatch is a relative newcomer. It became common in the late 1800’s, particularly among women. During the first world war, artillery officers found that a watch worn on the wrist was more practical than one carried in a pocket. Thereafter, the popularity of wristwatches grew.
Nowadays, most watches are electronic and utilize quartz crystals. When specially shaped and placed in a suitable electronic circuit, a piece of quartz vibrates at a constant frequency, acting like a rapidly swinging pendulum.
It is extremely difficult to adjust mechanical or quartz watches to keep exact time. So no matter what watch you have, it will to some extent gain or lose time. Today, however, quartz watches are available that periodically correct themselves using time signals from atomic clocks. Advertisers claim that such radio-controlled watches are accurate to one second in a million years!
SOME NOTEWORTHY WRISTWATCHES
▪ 1810-12
The first documented wristwatch, Abraham-Louis Breguet
▪ 1945
The date is displayed on the watch face, Rolex
▪ 1957
An electric-motor wristwatch, Hamilton Watch Company
▪ 1960
The time is kept through electronics, Bulova
▪ 1972
An all-electronic wristwatch with a digital display, Hamilton Watch Company
1 comments:
Very nice picture, and a prompt fix on an advertising issue I'd pointed out. Probably going to add you to my blogroll. Helps that you have a fairly clean layout with easy to identify content.
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