Q: What is a "complication"?
A watch "complication" is a watch function that does anything other than relay the time. Complications are additional features or mechanical additions to a watch over the standard time and date. For example, a chronograph is a common complication, as well as a day/date or big date. More exclusive complications include minute repeater, tourbillon and retrograde hands. For aficionados of high-end watches, the more complicated, the better.
Q: What is a Chronograph?
Watch or other apparatus with two independent time systems: one indicates the time of day, and the other measures (stopwatch function) brief intervals of time. Counters registering seconds, minutes and even hours can be started and stopped as desired. It is therefore possible to measure the exact duration of an event. There are many variations on the chronograph. Some operate with a center seconds hand, which keeps time on the watch's main dial. Others use sub-dials to time elapsed hours, minutes and seconds. Still others show elapsed time on a digital display on the watch face. Some chronographs can be used as a lap timer ("flyback hand" and "split seconds hand"). The accuracy of the stopwatch function will commonly vary from 1/5th second to 1/100th second depending on the chronograph. Some chronographs will measure elapsed time up to 24 hours. Watches that include the chronograph function are themselves called "chronographs." When a chronograph is used in conjunction with specialized scales on the watch face it can perform many different functions, such as determining speed or distance (see "tachometer"). Do not confuse the term "chronograph" with "chronometer." The latter refers to a timepiece, which may or may not have a chronograph function that has met certain high standards of accuracy set by an official watch institute in Switzerland.
Q: What is a Chronometer?
Technically speaking, all watches are chronometers. But for a Swiss made watch to be called a chronometer, it must meet certain very high standards set by the Swiss Official Chronometer Control (C.O.S.C.). If you have a Swiss watch labeled as a chronometer, you can be certain that it has a mechanical movement of the very highest quality-- undergone a series of precision tests in an official institute. The requirements are very severe: a few seconds per day in the most unfavorable temperature conditions (for mechanical watches) and positions that are ordinarily encountered.
Q: What is a tourbillon?
In horology, a tourbillon or tourbillion ("whirlwind") is an addition to the mechanics of a watch escapement. Invented in 1795 by Swiss watchmaker Abraham-Louis Breguet, a tourbillon counters the effects of gravity by mounting the escapement and balance wheel in a rotating cage, ostensibly in order to negate the effect of gravity when the timepiece (and thus the escapement) is rotated. Originally created in attempts to improve accuracy, tourbillons are still included in some expensive modern watches as a novelty and demonstration of watch making virtuosity. The mechanism is usually exposed on the watch's face to
show it off.
Q: How does a tourbillon work?
Gravity was thought to have a very adverse effect on the accuracy of time pieces at the time of the invention of the tourbillon, particularly because pocket watches were often less accurate than stationary clocks of the same construction. The prevailing theory amongst horologists of the time was that pocket watches suffered from the effects of gravity since they were usually carried in the same pocketed position for most of the day, which was vertical, and then held in a different position while being read. Because the movements of pocket watches and similar pieces were oriented with respect to the cases and the dials, their movements were positioned with the axes of motion perpendicular to their faces. This meant that when the timepiece was placed vertically, the axis of motion of the movements would be parallel to the ground, and thus the force of gravity. In such a position, the force of gravity would affect the motion of parts of the movement differently when the parts were in different positions (i.e., moving with gravity or moving against it), which would cause variations in the rate of the movement, which in turn would affect the timepieces' accuracy. If adjusted for one position, the rate would change when the piece was kept in a different position, such as when being held to be read or when placed on a table at night. In a tourbillon, the entire escapement assembly rotates, including the balance wheel, the escape wheel, the hairspring, and the pallet fork, in order to average out the effect of gravity in the different positions. The rate of rotation varies per design but has generally become standardized at one rotation per minute. Most tourbillons use standard swiss lever escapements, but some have a detent escapement, and others contain novel designs. The tourbillon is considered to be one of the most challenging of watch mechanisms to make (although technically not a complication itself) and is valued for its engineering and design principles. Breguet produced the first tourbillon mechanism, which was crafted for Napoleon in one of his carriage clocks (travel clocks of the time were of considerable weight, typically weighing almost 200 pounds).
Q: What is a “mechanical watch”?
A mechanical watch is a watch that uses a non-electric/electronic mechanism to measure the passage of time. It is driven by a spring (called a mainspring) which must be wound periodically, and which releases the energy to activate the balance wheel, which oscillates back and forth thanks to the Balance spring at a constant rate, transmitting the impulse through the lever escapement to the gear train, that divides the impulse into hours, minutes and seconds, thus making a 'ticking' sound when operating. Mechanical watches evolved in Europe in the 1600s from spring-powered clocks, which appeared in the 1400s. Mechanical watches are not as accurate as modern quartz watches and are generally more expensive. They are now worn more for their aesthetic and emotional attributes, as a piece of jewelry and as a statement of one's personality, than for their timekeeping ability.
Q: What are “jewels” in a watch?
Jewels are bearings in a watch movement made of ruby, sapphire, crystal, or synthetic ruby. Generally, the steel pivots of wheels turn inside jewels (mostly synthetic rubies) lubricated with a very thin layer of special oil. The jewel's hardness reduces wear to a minimum even over long periods of time (50 to 100 years). Most refined jewels have rounded holes and walls to greatly reduce the contact between pivot and stone. The quality of a watch is determined more on the shape and finishing of jewels rather than their number.
Q: Why are “jewels” used in watches?
Jewels serve two purposes in a watch. First, reduced friction can increase accuracy. Friction in the wheel train bearings and the escapement causes slight variations in the impulses applied to the balance wheel, causing variations in the rate of timekeeping. The low, predictable friction of jewel surfaces reduces these variations. Second, they can increase the life of the bearings. In unjeweled bearings, the pivots of the watch's wheels rotate in holes in the plates supporting the movement. The sideways force applied by the driving gear causes more pressure and friction on one side of the hole. In some of the wheels, the rotating shaft can eventually wear away the hole until it is oval shaped, and the watch stops.
Q: What is a “quartz” watch movement?
A quartz watch movement is a movement powered by a quartz crystal. Quartz crystals are very accurate. They can be mass-produced which makes them less expensive than most mechanical movements, which require a higher degree craftsmanship.
Q: What's the difference between a "manual" and an "automatic" watch?
An "automatic" wristwatch is a mechanical wristwatch with a self-winding mechanism. In other words, one does not have to wind the crown periodically to keep the watch running. A "manual" or "manual wind" watch must be wound by hand, using the crown, usually every day, to operate continuously. If one were going to own only a single watch, and wear it every day, an automatic would be a good choice, since the watch will be worn consistently enough to stay wound - the owner would never need to manually wind the watch, and would only need to adjust the time to compensate for drift and at changeover to daylight/summer time and back. (In fact, several early automatic movements dispensed with the crown and moved the time-setting mechanism onto the back, under the theory that the mechanism would only be accessed infrequently. This turned out to be a marketing flop - people liked the look and easy accessibility of the crown.) For this reason, most commonly seen watches with more than a simple date window use automatic movements - this includes "triple date" calendars, annual calendars, perpetual calendars, and any of these combined with moonphases. With few exceptions, most manual wind watches have simpler calendars, although they may include other complications like chronographs.
Q: What is a “watch winder,” and do I need one?
Collectors who have more than one automatic watch may have difficulty keeping any one watch going continuously. This leads to increased inconvenience if calendars and moonphases must be reset. A solution has been invented - the automatic watch winder. The idea is quite simple: strap the automatic watch to a motor, which then moves the watch enough to keep it wound when not worn on the wrist. That way, one can choose to wear any watch at any time, and not have to reset the time or calendars. More importantly, using a watch winder will keep the watch rotating and thus preventing the oils and lubricants in the watch from drying up and causing damage over time.
Q: What is a perpetual calendar?
This is a watch with the day/date/year indicators and is called perpetual because it automatically adjusts to months with 30 days and to the 28 or 29 days in February. Unless it takes into account century years that are not leap years, it will need adjusting in 2100, 2200 and 2300 (because of a glitch in the Gregorian calendar), so when you bequeath the watch to your heirs be sure to leave instructions.