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| Watches
and Clocks |
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Clocks
and Watches - devices used to measure or indicate the passage
of time. A clock, which is larger than a watch, is usually
intended to be kept in one place; a watch is designed to be
carried or worn. Both types of timepieces require a source
of power and a means of transmitting and controlling it, as
well as indicators to register the lapse of time units |
Throughout
history, time has been measured by the movement
of the earth relative to the sun and stars. The earliest
type of timekeeper, dating from as far back as 3500BC,
was the shadow clock, or gnomon, a vertical stick or
obelisk that casts a shadow. An Egyptian shadow clock
of the 8th century BC is still in existence. |
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The
Mechanical Clock The historical origin of the
mechanical clock is obscure. The first recorded examples
are found in the 14th century. Until that time, a time-measuring
instrument was known as a horologium, or hour teller.The
name clock, which originally meant "bell,"
was first applied in the present sense to the huge,
mechanical time indicators installed in bell towers
in the late Middle Ages. |
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The
Pendulum A series of inventions in the 17th
and 18th centuries increased the accuracy of clockworks
and reduced the weight and bulk of the mechanisms. Galileo
had described late in the 16th century the property
of a pendulum, known as isochronism, stating that the
period of the swing is constant. In 1657 Dutch physicist
Christiaan Huygens showed how a pendulum could be used
to regulate a clock. Ten years later English physicist
Robert Hooke invented an escapement, which permitted
the use in clocks of a pendulum with a small arc of
oscillation. British clockmaker George Graham improved
the escapement, and John Harrison developed a means
of compensating for variations in the length of apendulum
resulting from changes in temperature. |
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Watches
Watchworks were developed when coiled springs were introduced
as a source of power. This type of spring was used in
Italy about 1450. About 1500 Peter Henlein, a locksmith
in Nürnberg, Germany, began producing portable
timepieces known popularly as Nürnberg eggs. In
1525 another artisan, Jacob Zech of Prague, invented
a fusee, or spiral pulley, to equalize the uneven pull
of the spring. Other improvements that increased the
accuracy of watches included a spiral hairspring, invented
about 1660 by Robert Hooke, for the balance wheel, and
a lever escapement devised by British inventor Thomas
Mudge about 1765.
Minute and second hands, and crystals to protect both
the dial and hands, first appeared on 17th-century watches.
Jeweled bearings to reduce friction and prolong the
life of watchworks were introduced in the 18th century.
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| Basics |
Movements
- a watch's movement is the internal operating mechanism
of a time piece. Today, most watches are battery operated
and their movements are called quartz movements. A small
battery activates a tiny quartz crystal whose rapid
vibrations are changed by a microcomputer chip into
energy to run the watch.
The old hand-wound watches all people used to wear featured
mechanical movements. |
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Mechanicals
are driven by a mainspring connected to gears and a balance
wheel. The stem you wind on a mechanical watch activates the
mainspring, which then starts the watch without need of a
battery. Watch connoisseurs today still delight in the intricacies
of mechanical movements and some of the most expensive watches
in the world continue to feature them.
Analogs - An analog watch features the old fashioned face
we know best the one with the hour and minute hands. Digital
watches are the other kind; they feature numerals printed
out on a display panel.
Chronographs - A chronograph is essentially a watch that features
stopwatch functions (that means it has a timer you can start
and stop) and it is one of the most popular timepieces on
the market. Watches that are called chronographs also perform
normal timekeeping tasks, but they can do much more, Some
chronos simply feature a hand that measures seconds. Others
are more complex and can time longer or shorter periods or
elapsed time. Chronographs can also determine speed or distance
or time more than one event simultaneously. As writer and
humorist Mark Twain once said while marveling about his watch:
"It knows considerable more than the average voter."
He might have been referring to today's chronographs.
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Adidas, Accutron, Aqualand
Armani, Audemars; |
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Baby-G, Baume et Mercier, Blancpain,
Blue Angels, Breguet, Breitling, Bulova; |
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Cartier, Cassio, Chaumet CK, Citizen,
Coinwatch, Compass Concord, Corum; |
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Divers |
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ESQ, Esprit Fossil, Franchi Menotti; |
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Gallet, G-shock; |
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Hamilton, Harley Davidson, Heuer,
Horology; |
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Invicta, IWC; |
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Jaeger, Jaques du Manoir, Jean Marcel; |
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LeCoultre, Lego; |
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Michaelis, Mickey Mouse, Minnie
Mouse, M&M, Movado, Mueller; |
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Omega, Oris, Patek Philippe, Piaget,
Pierre Cardin, Promaster, Pulsar; |
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Rolex |
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Sector, Seiko, Sksgen, Swatch, Swiss,
Swiss Army; |
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Tag Heuer, Thunderbird, Tiffany,
Timex, Torracio Tudor; |
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Vacheron, Weil, Ebel, Wenger, Wittnauer; |
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Baldwin, Braun; |
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Elgin Clock; |
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Gorham |
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Howard Miller; |
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Linden |
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New England Clock; |
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Reed & Barton; |
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Salton Time, Seiko; |
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Timex |
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Westclox; |
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Zenith |
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