Interesting annular solar watches, one of the options for the road – and they both served as decorative pendants. The main part was brass ring of a few centimeters in diameter, combined with other mobile ring equipped with a hole to the solar beam. At the outer surface of the main ring engraved initials months, but against them on the inner surface, was the hour scale. Before the measurement it was necessary to rotate the lower ring, so that the hole for the beam was the name of the desired month. To measure the time clock exhibited so that the ray of sunlight passed through the hole and said hour scale. The first description of the hours – in a ring with a seal – in the book doctor Bonn, was published in Paris in 1500.

One of the most popular varieties of solar traffic hours were so-called lamellar hours. The first copies have appeared in Europe in the years 1451-1463. They usually consisted of two, sometimes three of the same size square of rectangular plates, pendants connected with the bottom plate must be a compass.

There is a description of octagonal wooden sticks with length 160 cm, with a metal tip and carved hour scales. This sundial (ashadah), which had in the Middle Ages, Indian pilgrims. In the handle of this stick is usually pierce through four holes, in which over a scale for the corresponding month slide rod length of about 15 cm so that its edge in the upright stick is casting its shadow on the scale. At the stick was to be 12 scales. As the days away from the solstice at the same time, the same operating conditions, it was enough to have the 8 scales. Name «ashadah» those hours were on the season (June – July), in which the pilgrimage.

Since the beginning of XVI century, the theory of the solar clock started teaching at Wittenberg University, Tübingen, Ingoldshtadta in Prague and Hradec Shtirskom as part of mathematics. Around the same time, there were windows sundial. They were vertical, they face the surface of the window was the church or town hall. The dial is usually consisted of a mosaic panels, filled with lead. Arrow is casting its shadow on the dial, arranged so that the end of the shade, not only watches, but also of the Sun in the zodiac. Transparent Scale allowed to observe the time, without leaving the building.

There were mirrored dial to reflect a mirror at the sunbeam dial, located on the wall of the house. The first such clock JB Benediktus described in the book, published in Turin in 1574. According to some sources, the construction of mirror of hours worked and Nicholas Copernicus, which you can believe, because so far remained on the clock face mirror Castle in Olsztyn presumably his work.

With precision sundial could not match the mechanical, before they began to apply the pendulum oscillator. But after his appearance sundial retain their popularity. The greatest flowering of the production has reached in the XVI and XVII centuries, their creation is at the European mathematics and astronomy. In addition, they remained very long mandatory affiliation of all observatories. Even in the XVIII century of astronomical observatories built in the East, for example in India. Yayi Singh II, Prince of Jaipur, founded in the years 1708-1710 a large observatory in Dilli, put there gnomon height of 18 meters. Shortly thereafter, he ordered to build a similar clock in Benarese, Muttrzhe, Uygaine and Jaipur.

Tags: clock, portable clock, Solar clock, Solar portable clock

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