First introduced at the meter stick was erected in the country, which enabled people to deduce quite accurately how much of the day had passed, and how much was still left before sunset.Stick threw a shadow over the country, which moved as the sun in the sky. For this primitive ajanmittarista was developed around 3500 BC. sundial, which was the first real timer clock type. Even the projection, the shadow moved round the sun, the twelve sectors shared platform.
These sectors responded to twelve hours a day, but at the time, an hour was not yet well established. Therefore, the day, and therefore also for the hours, varied in length, among other things, according to the seasons. The sundial was long the dominant measure of time, but it was impractical for the fact that its performance was closely tied to solar light. If the sky was cloudy and it was night, the sun does not have to use the timer clock as the light of the sun does not cast a shadow.
Only solution to the problem came when the first water stopwatch timer clocks were developed in Egypt about 3 400 years ago. Water timer clock was a water-filled container, the bottom of which was a small hole. Water leaked into this hole little by little out of time and was able to verify by looking at how much water was left.
The 700's were invented a revolutionary new measure of time: sandglass or hourglass. Its principle of operation was basically the same as the water timer clock. Hourglass had two containers on top of the sand, and the time was measured from the upper drainage of the lower container. At such a speed hourglasses identify any prior period indicators.
Pope Sylvester II, said to have invented the pendulum timer clock in around 990, [1], but only after the year 1280 was developed in Bedfordshire in England, at first, which worked by gravity, churches, tower timer clocks became common in Europe. At containing the pinion and weight of the cast, and at best only the actual time of about 15 minutes to one day. 1400s became more common jousivetoiset and portable timer clocks and the early 1500s began to appear in the pocket watches.
1580's Galileo Galilei (1564-1642) discovered that the same length of the pendulum oscillation time does not depend on the size and the weight of the swing angle, but it is a constant. Dutchman Christiaan Huygens (1629-1695) developed the first usable pendulum timer clock.
Earlier timer clocks were usually only the hour hand. Minutes and the seconds were tested in the late 1500s, but the minute hand became common only in about 1680, the second hand a little later. [2]
Online timer clocks of the development of the people's perception of time has changed. It was seen as a stream, but the timer clocks allows it turned into small periods of time units. Wristwatch became common in the 1800s among women. During the First World War, men's wristwatch was also transferred to gradually displace the use of a pocket watch.
In the 20th century was discovered a number of new, more former watches. Quartz timer clock was used for scientific purposes in the 1930s, and the end of the century it became common in everyday life. Even more accurate is the spectral lines of atoms based on the frequencies of the atomic timer clock, which is also based on units of time, seconds, the current definition.
In recent decades, has become a radio signal to the correct time receiving watches. Atomic timer clock can be sent to the long-wave broadcast of a very specific time and date, which helps to keep quartz watch more precisely in time. In this case, the summer and winter time timer clock is set automatically. In Europe the standard is the standard German Mainflingenistä sent to the DCF77 signal. Station began in 1973, the time of transmission. Also operates satellite time were defined as the need for satellites to locate the exact time that they send the tracking devices.
