Prague Astronomical Clock (Orloj)

Charming Prague Hotels | 22. 6. 2015

Prague Astronomical Clock / Orloj - it is a clock with a history line. It has many astronomical features and entertains every tourist who comes to visit Prague. You can see the Apostles‚ playing their roles‘ at the chime of every hour.

Beauty of the Prague Astronomical Clock combined with hourly mechanical "show" thrils the crowds that gathers below it, even with still 15 minutes to go...
An experience that everyone who comes to Prague should make to understand the magic of the Orloj and charm of historical Prague (more about Prague here).

Description of Prague Astronomical Clock

It consists of three parts:
The calendar in lower part.
The Sphere or Clock Dial in the center.
The walk of the apostle at the top.

The Calendar of Prague Astronomical Clock :
The Calendar features month symbols by czech painter Josef Manes from 1805. 
(you can find the originals in Prague Museum of History)

The Sphere of Prague Astronomical Clock (Clock Dial) :
It is the central part of the Prague Astronomical Clock with astronomical features such as ancient Czech and present day time, sunrise and sunset, movements of the Moon and the Sun and other celestial configurations for Prague.

There are three independent movements:
revolutions of the Sun (mean)
revolutions of the Moon (mean)
revolutions of the stars - ecliptic (apparent)
Astronomical night is displayed by dark circle at the bottom.
Three pointers rotate around this dial :
for the Sun
for the Moon 
for zodiac
boundary of blue and red indicates the horizon
left part indicates the day-break (AVRORA) with a rising border (ORTVS)
right part showes the twilight (CREPVSCVLVM) with a setting border (OCCASVS)

The walk of the Apostles:
In the upper part of the Prague Apostolic Clock The Apostles come out of the window.
From the right window :
St. Peter with a key is the first one – the patron saint of locksmiths, clockmakers and fishermen.
St. Mathew with an axe is next – the patron saint for carpenters, builders, blacksmiths and butchers.
St. John castigating a snake - the patron saint of writers and printers
St. Andrew with a cross
St. Philip with another cross - the patron saint for hatters
St. Jacob with a tool for working flax - the patron saint of linen traders
From the left window :
St. Paul is first holding a sword and a book
St.Thomas carrying a spear is next
St. Juda Tadeus holding a book in his left hand
St. Simon holding a saw - the patron saint of lumberjacks
St. Bartholomew with a book - the patron saint of tailors, tanners and shoemakers.
St. Barnabas (Nathael) carrying a papyrus is last
Bellow are the other statues, which are fixed.
Death is represented by a skeleton pulls the bell cord with one hand holding the clessidra in the other.
The Apostles are in a procession (the top part of the Prague Apostolic Clock).

When the windows close, a cockerel flaps, crows in an alcove and you can lisen to the chimes of the hour.
All accompanied by the Turk shaking his head, Vanity admiring himself in a mirror and by the Miser watching his bag.
The other eight figures

There is a pair of moving statues on both sides of the clock dial and calendar.
The four figures at the top were seen as the four menacing elements for the city of Prague, in the past. 
They remain standing all the time at the same place, but they have moving parts.
Right top to the Prague clock dial
A Turk called The Piper
Death (rings the bell)
Left top to the Prague clock dial
The Miser/Jew (holding onto his bag of gold)
The Vanity (admiring himself in a mirror)

The four immobile virtues are at the bottom
Right bottom to the Calendar
A Philosopher
An Astronomer 

Left bottom to the Calendar
An Angel
A chronicler

The Clockwork of Prague Astronomical Clock
There are three great co-axial wheels of the same diameter, driven by the same pinion, with 365, 366 and 379 cogs. 
The first is gearing the zodiac and the indicator with the asterisk rotates once a sidereal day.
The second one gears the indicator of the Sun and rotates once a mean solar day.
The third one gearing the Moon‘s pointer rotates accordingly with the mean apparent motion of the Moon. 
The ball, half black and half silvered, rotates every synodic month and displays its phase.
Basic intention
The concept of the Prague Orloj as an astronomical clock, was to represent the course of the stars and sun just like the real thing and the main task was to the exact point in the afternoon when the sun was at it highest in Prague. This is why the Prague Orloj was always timed to the real sun time using sun dials (vertical sticks dependant on sun and shadow to measure time). It was necessary to keep correcting clock works, comparing clocks with other clocks and the best way to do this was according to the sun dials. Initially - clocks, the Prague Orloj included, were ‚tuned‘ according to the local sun position and had to be continually ‚corrected‘ accordingly. In fact there were two sun dials on both sides of the location of the Prague Orloj clock and the remains of these on the Prague Old Town Hall walls were visible until 1911. Soon clocks could run with more precision than sun dials and were based on the central local sun position. These were the starting phases of the Prague Orloj.
Astronomers then came to synchronizing the precision of clocks according to star configurations and their movement around the Earth. Further developments made it necessary or viable to be able to divide time into units. 
The Prague Astronomical Clock is one of the oldest European clocks of its kind (the first ever originated in Padua in 1344 and a second in Strasbourg in 1354). Being the oldest of those where the original clockwork has been in operation from the beginning to the present time for six centuries, and even the astronomical dial shaped like an astrolabe survives in the original form.
The Prague Clock showed only astronomical data at first and there were no irrelevant little mechanical figures to entertain the people…

Myths and Legends
There are many legends about Prague Astronomical Clock, but the most famous is about the master clockmaker Hanus.
The Old Town Councilors are said that they had his eyes burnt out with a hot poker, to ensure that he would not be able to build another „Orloj“ elsewhere to overshadow the beauty and the fame of the Prague Clock.
Master clockmaker Hanus then allegedly asked his apprentice to take him to the clock. He deliberately damaged it so seriously, that nobody could repair it. Those who tried to repair it either died trying, or have gone mad. 
Clock really was not very reliable and often did not work, in spite of extensive repairs at the beginning... 
A further myth gives the Skeleton figure magical power of foretelling the future.
It says that if Prague clock is left unrepaired for a long time, hard times will follow for the Czech nation.

The lone tower housing the present day Prague Astronomical Clock was built in 1381. The clock was installed in 1410 by clockmaker Mikulas of Kadan with the astronomer and professor of mathematics at Prague Charles University - Jan Sindel.
The craftsman Hanus Carolinum did some repairs in 1490 and has added the calendar dial under the astronomical dial. Than the entire facade of the Prague Orloj was richly decorated with striking Vladislav Gothic – (Flamboyant Gothic) - stone sculptures. Exceptions are the sculptures flanking the astronomical mask, figures and dial on its architrave created at the beginning of the 15th century by members of the masonic lodge of stonemasons and sculptors led by Peter Parler (great Prague architect).
Major repairs were done by Jan Taborsky between 1552 and 1560.
Around 1566 the Orloj was mechanized and the tasks of the „Orlojners“ were to monitor the working of the clock and to fix breakdowns.
In the following years was the Prague Astronomical Clock neglected and damaged.
At the beginning of the 17th century (around 1613) was repaired by Kristof Svarcpach. Than was the Prague Astronomical Clock kept running down until it stopped completely. Small repairs were applied after the thirty year war in 1648 but got the Prague Orloj running always for only a few weeks… 
New statues were added towards the end of the 17th century - moving statues in particular the Death that tolls the bell by the side of the astronomical dial and immobile ones alongside the calendar dial were added. Still there was no money for major repairs and even worse - no capable watchmaker to do them.
In 1787 the whole mechanism nearly went for sale (as scrap iron). 
Watchmaker Jan Landesberg trying to repair the mechanical part was not very successful… (the astronomical calendar and other parts of the mechanism had to wait another hundred years).
Major restructuring of the whole Prague Astronomical Clock in the 1860s gave it the newdays aspect.
In 1861 the Town didn‘t have another 4000 gold pieces necessary to repair it and Prague Astronomical Clock was up for sale once again. Fortunately, a collective sum was raised eventualy and the Orloj was not sold.
In 1864 the Apostles statues from Eduard Veveleho were destroyed due to a fire.
Jan Holoub with the supervision of watchmaker Ludvik Hainze from Prague and advice from F. Bohm repaired Prague Astronomical Clock in 1865 and new calendar disc by the well-known Czech painter Josef Manes was installed (the cycle of twelve medallions of the zodiacal signs and twelwe medallions of Months is one of his greatest works). Later have been replaced by a copy from Bohumil Cilli and the originals are in the City Museum.
On the 18th of August 1866 the Prague Astronomical Clock was unveiled amidst festivities as ‚he‘ had been finally repaired to the present state - just to be closed down to have all the mechanisms re-lubricated, the last defects repaired and to connect it all together so that the calendar plate would work too.
On the 14 th September 1866 the Prague Astronomical Clock was functioning as everyone in the past 400+ years involved only imagined.
Than it was maintained by Ludvik Heinz until his death in 1874. His son Ludvik Heinz followed and from the year 1901 another Ludvik Heiz - his nephew.
In 1945 the whole structure was damaged in the final phases of WWII and the Prague uprising. Number of self-sacrificing persons managed to repair the authentic old clockwork than.
The original figures of the Apostles have been replaced by Vojtech Sucharda - the woodcarver.
The Orloj was completly renewed in 1948 - on the 1st of July.
The last major repair was undertaken in 1979.
Its hard to believe that Prague Astronomical clock are quite offen targeted by vandals!
Sometimes they even break away parts of sculptures or demage stone parts of Prague Astronomical clock.
Thats why it became nearly monitored by Prague police, which is now able to strike within a few seconds….
The future of mechanical clocks is unclear, however. Tower clocks in Germany and Austria have already been mostly replaced by electronic timing mechanisms….

A bit about Johannes Sindel (Prague astronomer from the very beginning)
Magister Johannes is the astronomer who helped the clockmaker Nicolaus of Kadan to construct the famous Prague Astronomical Clock arround 1410. He also performed valuable astronomical observations - according to Tycho Brahe. Magister Johannes was born arround 1375 in Hradec Kralove (Bohemian town). He became a bachelor in 1395 and master (magister arcium) on Prague University in February 1399. He was the rector of the St. Nicholas school in from 1406. He was also a teacher of mathematics in Wien (he studied on the Faculty of Medicine here too). Than he became a professor of astronomy on the Charles University in Prague. 
Later, he became a doctor of medicine, the rector of Prague University and private physician of the king Wenceslas (Karel) IV. He was a friend of John Hus (big person of czech history) and in the period of Hussite wars (after religious murder of mister John Hus in Constanc) he was in exile in the Moravian town Olomouc.
Later he was the physician of the town Nurnberg (1423-1436). From 1432 he was private physician of the emperor Sigmund - brother of the king Wenceslas (Karel) IV (biggest czech king in the history). He returned to Prague in 1436 and in 1441 he became the dean of Vysehrad capitol. He died arround year 1456 in Prague.

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