Chronograph - a common and very practical complication of mechanical watches. This is additional independent device for measuring time intervals. Most functionally it in sports watches, watches for pilots and military, as well as for research work - wherever needed convenience and accuracy of measurement.
The first device for precise time measurement was invented in 1720 by George Graham, and in 1862 Adolph Nicole has created a chronograph with three functions: start, stop with the fixation of result and reset. These functions are basic in modern chronograph. The first chronograph in the form of a wristwatch developed in 1910 by Gaston Breitling. They were intended for pilots. The control of these chronographs was carried out using a single button, so the functions start, stop and reset can be activated only in sequence. One-button chronographs available today, but it is more practical to control with two buttons, proposed Breitling in 1934. One button does start and stop the chronograph, the second - zeroes the result. This greatly enhances the ability to measure, allowing you to make intermediate stops without resetting the current readings.
Chronographs received great popularity thanks to the military, allowing easy and convenient to measure runtime of tasks, thus helping in the planning and development strategies. Chronograph function has become traditional for military timepieces. It is also great equipment for athletes who often use it during practices.
To display the chronograph functions, as a rule, you have additional sub-dials. In various modifications its number may vary. Basic chronograph dials - with indication of seconds and minutes. More complex models have a sub-dial, which allows you to time events lasting up to 12 hours. There are also versions with additional features such as split-chronograph and fly-back.