Almost since the mechanical watch was invented the most talented horological minds considered the full potential of timing machines. Watches today tell you the hours and minutes, but so many also offer additional information that builds on the idea of tracking or measuring time.
In the world of watches “functions” are often referred to as “complications.” In a sense you can consider a complication to be anything that offers an additional piece of information on a watch dial or way of showing information. Almost all complications stem from the core purpose of watches, which are to track time, so let’s take a look at some of the most common ones...
Chronograph literally means “time writer” and in a sense that is what some of world’s first chronographs did. Chronograph is the wrist watch term for stopwatch; essentially, a way to independently measure a portion of elapsed time. Chronographs have two important distinguishing features which help you understand them. Those being how long they can measure and the precision with which they can measure time. Having said that, a chronograph that can measure up to 12 hours is not necessarily better than one that only measure 30 minutes.
Mechanical chronographs typically measure with enough precision to measure down to one fifth of a second. Some go up to one eight or one tenth of a second. Certain models from TAG Heuer for example, can measure 1/100 to 1/1000 of a second, or more. But these ultra-precise mechanical chronograph movements are rare.
Chronographs tend to use independent hands on a watch dial to measure time, typically using smaller subdials. Chronograph watch cases also typically have two extra pushers, that serve to start, stop, or reset the chronograph. Exotic chronographs exists such as those with a single pusher to cycle through all functions, or ones that offer split timing.
It takes the moon about twenty nine and a half days to complete one full cycle. Moonphase watches track the phases of the moon with a visual indicator on the dial. In reality however the phaseof the moon is slightly different, and some of the world’s best moon phase watches are accurate for several hundred years (assuming the watch operates for that long).
Moon phase complications are typically beautiful and are typically appreciated for emotional versus practical reasons. Moon phases are sometimes displayed alone on a watch dial, but are often combined with other calendar data.
The most basic piece of calendar data on a watch is the date, the second being the day of the week. Some of the most beautiful watches only tell the time, but timepieces with the day and date on the dial arose for practical reasons and convenience.
Simple calendar complications like the day and date are available on watches of all prices and usually rely on discs under the dial to display the correct day and date via windows on a watch face. Many watches with a date complication need to be adjusted when months are shorter than 31 days. This isn’t the case with annual or perpetual calendar watches.
Watches that track a second time zone are often referred to as GMT timepieces. “GMT” stands for Greenwich Mean Time, and is sometimes also referred as “UTC.” The hallmark of a GMT watch is having a hand on the dial which makes a one full revolution each 24 hours. True GMT watches offer time in a 24 hour format so that a second time zone can be tracked anywhere in the world where you can know whether it is AM or PM in that time zone. There are however many timepieces that offer two times which are both in 12 hour formats. More complicated GMT watches offer simple world time complications that make it easier to see the time zone in places all over the world. GMT watches with a rotating bezel that has a 24 hour scale on it can be used to track a third time zone.
Mechanical alarm watches use a secondary tightly wound spring that when released causes a buzzing reminder at a specified time. New mechanical alarm watches are rare as their noise isn’t particularly elegant, and their utility is often dwarfed by electronic alarms. While no mechanical watch is extremely practical compared to electronic devices, alarms seem to have suffered the worst.
Mechanical alarm watches typically have a dedicated alarm hand that is used to set an alarm time (precise to within a few minutes of when you want to be reminded) that occurs in the future. Each time an alarm is sounded the alarm spring needs to be rewound for it to work again. Some of the best mechanical alarm watches are easily loud enough to wake you up, and often louder than beeping digital alarm watches.
The most complicated calendar mechanisms on a watch are perpetual calendars. They are referred to as such because they never need to be adjusted (assuming the watch continues tooperate). Perpetual calendars are defined by being able to track (at least) the date, month, and leap year cycle.
Many perpetual calendars offer additional calendar data such as the day of the week or phase of the month. Perpetual calendars are the most expensive form of calendar and often include a great deal of information on a watch dial.
Watches with minute repeater complications literally “repeat” the time back to you via series of chimes that translate into what the time is. Minute repeaters originally existed in pocket watches, and before that large clocks or clock towers that uses bells. The miniaturization of this technology was meant as a luxury for the ultra-wealthy who wanted to know the time when it was too dark to read their clocks long before we used electricity.
Today the minute repeater exists as a homage to history and as a status items. Minute repeaters operate using a series of hammers which hit against gongs to produce small chimes. The quality and complexity of the sound can vary between minute repeater watch models. Many people consider minute repeaters to be among the most complex watches, which is why they are so desirable and expensive.
In French “tourbillon” means whirlwind and is sometimes not considered a complication at all because it does not technically add functionality to a movement. The tourbillon was invented in the 18th century as a theoretical means of reducing the accuracy-dampening effects of gravity of a watch’s escapement in pocket watches. Technically challenging, the tourbillon saw a resurgence of popularity about 20 years ago as item on very high-end luxury watch. What a tourbillon –style escapement does it put the entire escapement and balance wheel assembly in a spinning cage that revolves around its own axis. In addition to being difficult to assemble, tourbillons are often visually appealing, which is why they are usually prominently displayed on a watch dial.
ABOUT THE AUTHOR
Ariel Adams is founder and editor of world leading watch blog ABlogToWatch. He writes for Forbes.com and is a regular contributor to The Watch Gallery magazine. Read more articles by Ariel Adams. Follow Ariel on Twitter or Google+.