The Chronograph, Al-rashid Cyber Mall

Alrashid Cyber Mall

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The Chronograph: From the Ocean to the Moon

The chronograph is much more than a simple stopwatch. Although many owners of today's fine complicated watches may never use them to do anything more than boil the perfect three-minute egg, chronographs represented a major turning point in the hsitory of time-keeping. The development of accurate, resettable stopwatches elevated watches from just time keeping devices to sophisticated scientific tools.

The first chronograph, ironically, was also the last--technically speaking. Developed in 1821, it actually marked the passage of time with a small ink pen on the index. It was a true "chronograph" in the sense that it "wrote" the passage of time. Today's stopwatches are technically "chronoscopes" because they "show" the passage of time. But the term "chronograph" caught on better. The first waterproof chronograph was patented in 1933, followed closely by the first magnetically shielded chronograph. The first automatic, or self-winding chronograph watch was offered in 1969. Many modern chronographs have electronic quartz movements, such as the ones used to measure official time at races and sporting events.

Chronographs nowadays usually feature two extra buttons, usually on either side of the crown. One button starts and stops the chronograph, the other resets the hands to zero. The hands themselves are either located on subdials or, in the case of "split second" watches, on the central dial. Often people misunderstand the term "split second" to mean that the chronograph records time increments smaller than one second. What it really means is that the second hand is "split" into two hands--one to run in continuous time, the other to operate as a stopwatch. Some less expensive chronographs will feature only one second hand, which means that using the chronograph interferes with the measure of real time.

More expensive chronographs tend to have subdials. The more subdials, the more that can be measured. For instance, some chronogarphs will have three subdials: one to read seconds, one to record minutes, and another to record hours. This allows the user to record increments of time as long as 12 hours, rather than just one minute.

Chronographs also refer to a number of other measuring devices that were only developed for watches in recent years. One of these is a telemeter, which is a series of numbers on the bezel that are set according to the speed of sound. By using the stopwatch to measure the number of seconds that pass, for instance, between a flash of lightning and the sound of thunder, the telemeter numbers will indicate how many meters away the sound source is. This tool was especially useful in the military, where it could be used to estimate the distance of enemy artillery by calculating the time between a flash of light and the sound of the shot.

Another chronograph feature on some fine watches is a tachymeter, which also uses numbers on the bezel--only these numbers are calibrated to the distance of 1000 meters. By clocking the time needed to cover this set distance, the corresponding tachymeter numbers will indicate the velocity. Some medical watches have pulsometers, which have numbers that correspond to pulse rates based on 12 or 15 pulse beats.

Some watches have rotating bezels. On a slide rule feature this bezel rotates both ways, corresponding to a complicated set of numbers on the rim of the face. If you've ever used a slide rule, you know how much precision is needed to put this mini-calculator on a watch. In diving watches, the bezel is used to measure elapsed time--a crucial measurement when you have a limited air supply. These diving watches have bezels that rotate only one direction, counter-clockwise, and a glow-in-the-dark triangle at the top. Just before going underwater, the triangle on the bezel is turned to mark the time where the minute hand will be when the air supply will be nearly exhausted. When the minute hand meets the bezel marker, it's time to come up. Because the bezel can only turn one way, any accidental movement of the bezel will only err on the side of safety.

Chronograph watches made history in the NASA space program. The first watch on the moon was an Omega Speedmaster worn by Neil Armstrong, and became the official watch of the astronauts. During the the ill-fated Apollo 13 mission, the chronograph features on the Speedmaster became crucial to calculating operating parameters that were normally controlled by the malfunctioning spacecraft. NASA gave an award to Omega, and chronograph popularity soared soon after.

Some chronographs now have transparent "windows" on the caseback or face to show just how complicated the internal mechanisms are. Whether or not you ever dive underwater or fly into space, learning how to use the features on your chronograph will help you appreciate the fine craftsmanship of your watch.