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A gold pocket watch with hunter case and watch chain

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.

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

Early pocket watches

Antique verge fusee pocketwatch movement, from 1700s.

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.

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.

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.

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Open-face watches

An open-face pocket watch made by the famous Polish watchmaker Franciszek Czapek, circa 1876.

An open-faced watch is a watch in which the case lacks a metal cover to protect the crystal. It is typical for an open-faced watch to have the pendant located at 12:00 and the sub-second dial located at 6:00. Occasionally, a watch movement intended for a hunting case(with the winding stem at 3:00 and sub second dial at 6:00) will cased in an open-faced case. Such watch is known as a "sidewinder." Alternatively, such a watch movement may be fitted with a so-called conversion dial, which relocates the winding stem to 12:00 and the sub-second dial to 3:00. After 1908, watches approved for railroad service were required to be cased in open-faced cases with the winding stem at 12:00.

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 on open-faced watches, and at 5:00 on hunting cased watches. 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 time setting on pocket watches was preferred by American and Canadian railroads, as lever setting watches make accidental time changes impossible. After 1908, lever setting was generally required for new watches entering service on American railroads.

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. This style of watch is occasionally referred to as "nail set", as the set button must be pressed using a finger nail.

Jeweled movements

For more information, see Mechanical watch

Watches of any quality will be jeweled. A jewel in a mechanical watch is small, shaped piece of a hard mineral. Ruby and sapphire are most common, although diamond, garnet, and even glass are often seen. Starting in the early 1900s, synthetic jewels were almost universally used. Before that time, low grade natural jewels which were unsuitable as gemstones were used. In either case, the jewels have virtually no monetary value.

The most common types of jewels are hole jewels. Hole jewels are disks (normally flying saucer shaped) which have a carefully shaped and sized hole. The pivot of an arbor rides in this hole. The jewel provides an extremely smooth and hard surface which is very wear resistant, and when properly lubricated, very low friction. Thus, hole jewels both reduce friction and wear on the moving parts of a watch.

The other basic jewel types are cap jewels, roller jewels, and pallet jewels.

Cap jewels are always paired with hole jewels, and always with a conically shaped pivot. For a properly designed hole and cap jewel system, the pivot will always rest as a pin point on a thin film of oil. Thus, a hole and cap jewel offer lower friction and better performance across different positions as compared to simply a cap jewel.

The roller jewel, also called the impulse jewel or simply impulse pin, is a thin rod of ruby or sapphire, usually in the shape of a letter "D". The roller jewel is responsible for coupling the motion of the balance wheel to that of the pallet fork.

Pallet jewels interact with the escape wheel. They are the surfaces which, 5 times a second, lock the gear train of the watch and then transfer power to the balance wheel.

A jeweled watch should contain at least 7 jewels. The seven jewels include 2 hole jewels on the balance wheel, 2 cap jewels on the balance wheel, a roller jewel, and 2 pallet jewels.

More highly jeweled watches add jewels to pivots out from balance wheel, starting with the pallet fork, then the escape wheel, fourth wheel, third wheel, then finally the center wheel. Jeweling to the third wheel gives 15 jewels, jeweling to the center wheel gives 17 jewels. Thus, a 17 jewel watch is considered to be fully jeweled.

With American makers, however, it was common on low-end movements to jewel to the third wheel on only the top(visible) plate of the watch. This gives a total of 11 jewels, but looks identical to a 15 jewel watch unless the dial is removed. Since watches with 15 jewels and less are often not marked as to the jewel count, extreme caution must be exercised when movements which appear to be 15 jewels.

Additional jewels beyond 17 are used to either add cap jewels, or to jewel the mainspring barrel of the watch. Watches with 19 jewels, particularly those made by Elgin, will often have a jeweled mainspring barrel. 21 jewel watches commonly have cap jewels on both the pallet fork and escape wheel. 23 jewel watches will have a jeweled barrel and fully capped escapement. The timekeeping value of jewels beyond 17 for a time-only movement is often debated.

Complicated movements will often have additional jewels which do serve useful purposes.

Greater jewel counts are often associated with better quality watch movements. While it is true that expensive movements often have higher jewel counts, the jewels themselves are not the reason for this. The jewels themselves add essentially no monetary value, and beyond 17 offer a negligible improvement in timekeeping ability and in movement life. Most of the cost of a more expensive watch is associated with better quality finishing and, more importantly, with a greater number of adjustments.

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).

Positional adjustments are attained by carefully poising(ensuring even weight distribution) of the balance-hairspring system as well as careful control of the shape and polish on the balance pivots. All of this achieves an equalization of the effect of gravity on the watch in various positions. Positional adjustments are achieved through careful adjustment of each of these factors, provided by repeated trials on a timing machine. Thus, adjusting a watch to position requires many hours of labor, increasing the cost of the watch. Medium grade watches were commonly adjusted to 3 positions(dial up, dial down, face up) while high grade watches were commonly adjusted to 5 positions(dial up, dial down, stem up, stem left, stem right) or even all 6 positions. Railroad watches were required, after 1908, to be adjusted to 5 positions. 3 positions were the general requirement before that time.

Early watches used a solid steel balance. As temperature increased, the solid balance expanded in size, changing the moment of inertia and changing the timing of the watch. In addition, the hairspring would lengthen, decreasing its spring constant. This problem was initially solved through the use of the compensation balance. The compensation balance consisted of a ring of steel sandwiched to a ring of brass. These rings were then split in two places. The balance would, at least theoretically, actually decrease in size with heating to compensate for the lengthening of the hairspring. Through careful adjustment of the placement of the balance screws(brass or gold screws placed in the rim of the balance), a watch could be adjusted to keep time the same at both hot(100°F) and cold(32°) temperatures. Unfortunately, a watch so adjusted would run slow at temperatures between these two. The problem was completely solved through the use of special alloys for the balance and hairspring which were essentially immune to thermal expansion. Such an alloy is used in Hamilton's 992E and 992B.

Isochronism was occasionally improved through the use of a stopworks, a system designed to only allow the mainspring to operate within its center(most consistent) range. The most common method of achieving isochronism is through the use of the Breguet overcoil. which places part of the outermost turn of the hairspring in a different plane from the rest of the spring. This allows the hairspring to "breath" more evenly and symmetrically. Due to the difficulty with forming an overcoil, modern watches often use a slightly less effective "dogleg", which uses a series of sharp bends to place part of the outermost coil out of the way of the rest of the spring.

Decline in popularity

A pocket watch with an attached compass.

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.

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. 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.

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.

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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Simple English

[[File:|right|thumb|200px|A gold pocket watch]] A pocket watch is a timepiece that is kept in the pocket rather than worn on a wrist. The pocket watch usually has a chain to connect to a certain clothing, so the watch wouldn't fall out of the pocket and get broken. This watch was popular before the wristwatch came. Because of wristwatches, the pocket watch became less common and popular. Still, some people today wear pocket watches, and a golden pocket watch is often a token of a person's retirement.


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