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(dawn), the period after sunset as CREPUSCULUM (twilight).

2.Bohemian or Italian hours on the outer ring

On the outer ring, the hand with the little real hand indicatesthe Bohemian hours (also known as Italian hours). This kind of time was used in the Middle Ages in Bohemia, the country to which Prague belonged, and in Nord Italy.

The time of day plus night is divided in 24 hours. At sunset the hand indicates 24.At the drawing hereto the hand indicates 22, thus 2 hours before sunset.

To get this result the outer ring with the numerals rotates during one half of the year (when the days becomes longer) slowly to

the right and in the other half (when the days becomes shorter) to the left. The time indicated at the top at noon varies from 15:55 (still 8:05 hour to sunset) to 20:05 (still 3.55 tot sunset). The numerals are in Gothic style. is 4 is 7

3.On the zodiacal ring: the position of the sun in the zodiac and the sidereal time

On the zodiacal ring the little sun indicates the place of the sun in the zodiac. At the drawing hereto: the transition from Water bearer to

An asterisk is connected to the zodiacal ring,

Fishes, approximately at frebruar 18.

lengthening the dividing line between

Fishes and Ram (the vernal point). It indicates the

The zodiacal ring is placed excentrically in the clock. It rotates once in a

sidereal time, to be read on the scale with Roman

year around its own centre and on its own in one day around the centre of

numerals. At the first drawing hereto approximately

the clock. During this combined motion the little sun remains on the

00:20.

border of the zodiacal ring and on the hand.

4.The clock as a whole

The clock indicates five kinds of time: - the Central European Time;

- the time, measured in a division of twelve 'hours', between sunrise and sunset, the unequal or temporal hours. From day to day they are longer or shorter because the period between sunrise and sunset varies each day;

- the time, measured in a division of 24 hours indicating the time untill sunset (sunset = 24), the Bohemian or Italian hours; - the position of the sun in the zodiac;

- the sidereal time.Even the position of the moon is indicated. In the drawings hereto this is not depicted.

The clock consists of the stationary disk in the center and two

independently rotating disks, the outer ring with numerals in Gothic style and the zodiacal ring.

There are three pointers: the hand with the little real hand, the little sun moving back and forth on this handand the hand with the asterisk wich is connected to the zodiacal ring.

The astronomic clock on the old town hall of Prague consists of three parts:

1. At the top, behind two shutters, a kind of puppet show from the 19th century showing at each hour the figures of the twelve apostles. 2. At the foot in a circular calendar, pictures of the months and seasons and for each day the saint of the day.

3. In the middle, the oldest and most ingenious part, a multiple clock from 1410.

At the square near the clock each hour hunderds of tourists come together. The walking apostles attract their full attention. This spectacle takes less than one minute. About the clock itself they get mostly no information.

According to legend the maker of the clock in Prague, finishing his work, was made blind to prevent him to make a similar clock in an other town.