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Pocket watch

From Wikipedia, the free encyclopedia


A gold pocket watch with hunter case and watch chain
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A pocket watch (or pocketwatch) is a watch that is made to be carried in a pocket, as opposed to a wristwatch, which is strapped to the wrist. They were the most common type of watch from their development in the 16th century until wristwatches became popular after World War I during which a transitional design, trench watches were used by the military. Pocket watches generally have an attached chain to allow them to be secured to a waistcoat, lapel, or belt loop, and to prevent them from being dropped. The chain or ornaments on it is known as a fob. They often have a hinged metal cover to protect the face of the watch; pocketwatches with a fob and cover are often called "fob watches"; however no early references for the term, "fob watches" have been located. Also common are fasteners designed to be put through a buttonhole and worn in a jacket or waistcoat, this sort being frequently associated with and named after train conductors.
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An early reference to the pocket watch is in a letter in November 1462 from the Italian clockmaker Bartholomew Manfredi to the Marchese di Manta, where he offers him a 'pocket clock' better than that belonging to the Duke of Modena. By the end of the 15th Century, spring-driven clocks appeared in Italy, and in Germany. Peter Henlein, a master locksmith of Nuremberg, was regularly manufacturing pocket watches in England by 1524. Thereafter, pocket watch manufacture spread throughout the rest of Europe as the 16th century progressed. Early watches only had an hour hand, the minute hand appearing in the late 17th century.[1][2] The first American pocket watches with machine made parts was manufactured by Henry Pitkin with his brother in the later 1830s.

Contents

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Early pocket watches

Antique verge fusee pocketwatch movement, from 1700s.
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The watch was first created in the 16th century, initially in spherical (Pomander) or cylindrical cases, when the spring driven clock was invented. These watches were at first quite big and boxy and were worn around the neck. It was not for another century that it became common to wear a watch in a pocket.

Use in railroading in the United States

The rise of railroading during the last half of the 19th century led to the widespread use of pocket watches. Because of the likelihood of train wrecks and other accidents if all railroad workers did not accurately know the current time, pocket watches became required equipment for all railroad workers.
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The first steps toward codified standards for railroad-grade watches were taken in 1887 when the American Railway Association held a meeting to define basic standards for watches. However, it took a disaster to bring about widespread acceptance of stringent standards. A famous train wreck on the Lake Shore and Michigan Southern Railway in Kipton, Ohio on April 19, 1891 occurred because one of the engineers' watches had stopped for 4 minutes. The railroad officials commissioned Webb C. Ball as their Chief Time Inspector, in order to establish precision standards and a reliable timepiece inspection system for Railroad chronometers. This led to the adoption in 1893 of stringent standards for pocket watches used in railroading. These railroad-grade pocket watches, as they became colloquially known, had to meet the General Railroad Timepiece Standards adopted in 1893 by almost all railroads. These standards read, in part:
"...open faced, size 16 or 18, have a minimum of 17 jewels, adjusted to at least five positions, keep time accurately to within 30 seconds a week, adjusted to temps of 34 °F (1 °C) to 100 °F (38 °C), have a double roller, steel escape wheel, lever set, regulator, winding stem at 12 o'clock, and have bold black Arabic numerals on a white dial, with black hands."
Railroad employees to this day are required to keep their watches on time, and are subject to spot checks by their superiors at any time. Failure to keep their watches on time can lead to disciplinary action, due to the gravely serious safety issues involved.
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Additional requirements were adopted in later years in response to additional needs; for example, the adoption of the diesel-electric locomotive led to new standards from the 1940s on specifying that timekeeping accuracy could not be affected by electromagnetic fields.

Types of pocket watches

There are two main styles of pocket watch, the hunter-case pocket watch, and the open-face pocket watch.

Open-face watches

An open-face pocket watch made by the famous Polish watchmaker Franciszek Czapek, circa 1876.
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An open-face pocket watch is one with the winding-stem at the top of the dial, above the '12' or '3', commonly known as 'sidewinders' and with the seconds sub-dial at the 6 o'clock position. As the name suggests, these watches have cases which are without a cover to protect the watch-crystal from damage. All railroad chronometers had to be of the open-face kind.

Hunter-case watches

A hunter-case pocket watch is the kind with a spring-hinged circular metal lid or cover, that closes over the watch-dial and crystal, protecting them from dust, scratches and other damage or debris. The majority of antique and vintage hunter-case watches have the lid-hinges at the 9 o'clock position and the stem, crown and bow of the watch at the 3 o'clock position. Modern hunter-case pocket watches usually have the hinges for the lid at the 6 o'clock position and the stem, crown and bow at the 12 o'clock position, as with open-face watches. In both styles of watch-cases, the sub-seconds dial was always at the 6 o'clock position. A hunter-case pocket watch with a spring-ring chain is pictured at the top of this page.

Types of watch movements

Key-wind, key-set movements

The very first pocket watches, since their creation in the 16th century, up until the third quarter of the 19th century, had key-wind and key-set movements. A watch-key was necessary to wind the watch and to set the time. This was usually done by opening the caseback and putting the key over the winding-arbor (which was set over the watch's winding-wheel, to wind the mainspring) or by putting the key onto the setting-arbor, which was connected with the minute-wheel and turned the hands. Some watches of this period had the setting-arbor at the front of the watch, so that removing the crystal and bezel was necessary to set the time. Watch keys are the origin of the class key, common paraphernalia for American high-school and university graduation.

Crown-wind, crown-set movements

Created by Patek-Philippe in the 1850s, the crown-wind, crown-set movement did away with the watch-key which was a necessity for the operation of any pocket watch up to that point. The first crown-wind and crown-set pocket watches were sold during the Great Exhibition in London in 1851 and the first owners of these new kinds of watches were Queen Victoria and Prince Albert. Crown-wind, crown-set movements are the most common type of watch-movement found in both vintage and modern pocket watches.

Crown-wind, lever-set movements

Mandatory for all railroad watches, this kind of pocket watch was set by opening the crystal and bezel and pulling out the setting-lever, which was found at either the 10 or 2 o'clock positions. Once the lever was pulled out, the crown could be turned to set the time. The lever was then pushed back in and the crystal and bezel were closed over the dial again. This method of timesetting on pocketwatches was preferred by American and Canadian railroad staff, instead of the more common crown-wind, crown-set watches, because it was impossible, once the lever was pushed in and the bezel-closed, for the watch to be set to an erronous time by mistake.

Crown-wind, pin-set movements

Much like the lever-set movements, these pocket watches had a small pin or knob next to the watch-stem that had to be depressed before turning the crown to set the time and releasing the pin when the correct time had been set.

Jewelled movements

For more information, see Mechanical watch
Pocket watches made by the better watchmakers, such as Ball, Patek-Philippe, Waltham, Hamilton, Elgin, Illinois, Tissot and Rolex, to name a few, are often judged by how many jewels they have. Jewels are small gemstones (usually rubies, but also diamonds and sapphires), which are inserted into areas of a watch-movement which receive high-levels of motion, in order to prevent wear of parts and to help the watch run more smoothly. A lack of jewels would mean that metal parts (such as cogwheels), would be rubbing directly against other metal fittings (such as arbors), which would cause significant wear-and-tear over time. The purpose of jewels, together with proper lubrication-oils is to minimise just this kind of damage, which a movement can do to itself. 7 jewels is generally considered the lowest decent level of jewelling that a movement can receive. These seven jewels would be found in the watch's escapement, the mechanism which measures out the seconds and produces the watch's characteristic ticking sound. Other levels of jewelling include 11, 15, 17, 19, 21, 23 and 25 jewels. 17 and 21 jewels are generally considered the standard on all modern, well-made mechanical pocket watches. A high-quality pocket watch should have the movement's jewel-count engraved on the movement's top-plate.

Adjusted movements

Pocket watch movements are occasionally engraved with the word "Adjusted", or "Adjusted to n positions". This means that the watch has been tuned to keep time under various positions and conditions. There are eight possible adjustments:
  • Dial up.
  • Dial down.
  • Crown up.
  • Crown down.
  • Crown left.
  • Crown right.
  • Temperature (From 34-100 degrees Fahrenheit).
  • Isochronism (The ability of the watch to keep time, regardless of the mainspring's level of tension).
Adjusting a pocket watch is a long, tedious process which takes a lot of time, patience and above all, money. Adjusting a pocket watch's movement to all those eight positions is extremely expensive and most people will buy a watch with only two or three positions adjusted. Railroad chronometers had to be adjusted to five positions or more. As with jewelled movements, only the best movements were adjusted, due to the time and expense.

Decline in popularity

A pocket watch with an attached compass.
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Pocket watches are not common in modern times, having been superseded by wristwatches. Up until about the turn of the 20th century, though, the pocket watch was predominant and the wristwatch was considered feminine and unmanly. In men's fashions, pocket watches began to be superseded by wristwatches around the time of World War I, when officers in the field began to appreciate that a watch worn on the wrist was more easily accessed than one kept in a pocket. However, pocket watches continued to be widely used in railroading even as their popularity declined elsewhere.
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For a few years in the late 1970s and 1980s three-piece suits for men returned to fashion, and this led to small resurgence in pocketwatches, as some men actually began using the vest pocket for its original purpose.
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Since then, a few watch companies make pocketwatches, and they have their firm adherents. However, in the U.S.A. for most men, most of the time, a pocket watch must be carried in a hip pocket, and the more recent advent of mobile phones and other gadgets that must be worn on the waist has made the prospect of carrying an additional item in that area less appealing, especially as mobile phones and other electronic gadgets that a user may place in a pocket or holster usually have timekeeping functionality as well.
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In some countries a gift of a gold-cased pocket watch is traditionally awarded to an employee upon his or her retirement.[3]
The pocketwatch has regained popularity due to a sub-genre of cyberpunk known as steampunk, in which the pocketwatch is a common accessory. Steampunks tend to choose pocketwatches with visible gears and springs.

[edit] Watch manufacturers and manufactures

References

  1. ^ p. 2651, "Watch, Mechanical", vol. 19, How It Works: Science and Technology, 3rd ed., Marshall Cavendish, 2003, ISBN 0-7614-7333-5 (vol. 19), ISBN 0-7614-7314-9 (set.)
  2. ^ p. 253, The Grove encyclopedia of decorative arts, Gordon Campbell, vol. 1, Oxford University Press, 2006, ISBN 0195189485.
  3. ^ Van Horn, Carl (2003). Work in America: M-Z. ABC-CLIO. p. 236. ISBN 1576076768. 

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ILUSIONISMO
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* Victor Nogueira .
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Ele há um tempo p’ra tudo na vida
Cantando hora, minuto, segundo;
Por isso sempre existe uma saída
Enquanto nós estivermos neste mundo.
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Há um tempo para não fenecer
Há mar, sol, luar e aves com astros
Há uma hora p'ra amar ou morrer
E tempo para não se ficar de rastos.
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P'ra isso e' preciso sabedoria
Em busca dum bom momento, oportuno,
Com ar, bom vinho, pão e cantoria,
Sem se confundir a nuvem com Juno.
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1991.08.11 - SETUBAL