Techsciencenews Home 
 
 

Explore Inventors Biography Alphabetically

 

Home A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

  

Art | Business Studies | Citizenship | Countries | Design and Technology | Everyday life | Geography | History | Information Technology | Language and Literature | Mathematics | Music | People | Portals | Religion | Science | African Inventors | Invention Timeline | Space (Astronomy) | Main Menu

 

Elephant clock

The elephant clock in a manuscript by Al-Jazari (1206 AD) from The Book of Knowledge of Ingenious Mechanical Devices. [1]

The elephant clock was a medieval Muslim invention by al-Jazari (1136–1206), consisting of a weight powered water clock in the form of an elephant. The various elements of the clock are in the housing on top of the elephant. They were designed to move and make a sound each half hour.

A modern full-size working reproduction can be found as a centrepiece in the Ibn Battuta Mall, a shopping mall in Dubai, United Arab Emirates. Another working reproduction can be seen outside the Musée d'Horlogerie du Locle, Château des Monts, in Le Locle, Switzerland.

In addition to its mechanical innovations, the clock itself is seen as an early example of multiculturalism represented in technology. The elephant represents the Indian and African cultures, the dragon represents Chinese culture, the phoenix represents ancient Egyptian culture, the water work represents ancient Greek culture, and the turban represents Islamic culture.[2]

Contents

Mechanism

A reproduction of the elephant clock in the Ibn Battuta Mall, Dubai.

The timing mechanism is based on a water-filled bucket hidden inside the elephant. In the bucket is a deep bowl floating in the water, but with a small hole in the centre. The bowl takes half an hour to fill through this hole. In the process of sinking, the bowl pulls a string attached to a see-saw mechanism in the tower on top of the elephant. This releases a ball that drops into the mouth of a Serpent, causing the serpent to tip forward, which pulls the sunken bowl out of the water via strings. At the same time, a system of strings causes a figure in the tower to raise either the left or right hand and the mahout (elephant driver at the front) to hit a drum. This indicates a half or full hour. Next the snake tips back. The cycle then repeats, as long as balls remain in the upper reservoir to power the emptying of the bowl.[3]

Automaton

This was the first clock in which an automaton reacted after certain intervals of time. In the mechanism, a humanoid automata strikes the cymbal and a mechanical bird chirps, like in the later cuckoo clock, after every hour or half hour.[4]

Passage of temporal hours

Another innovative feature of the clock was how it recorded the passage of temporal hours, which meant that the rate of flow had to be changed daily to match the uneven length of days throughout the year. To accomplish this, the clock had two tanks, the top tank was connected to the time indicating mechanisms and the bottom was connected to the flow control regulator. At daybreak the tap was opened and water flowed from the top tank to the bottom tank via a float regulator that maintained a constant pressure in the receiving tank.[5]

Flow regulator

The mechanism employed a flow regulator, which was used here to determine the time when the clock strikes at hourly intervals. The hourly intervals were determined with the use of a small opening in a submersible float, which was calibrated to give the required rates of flow under different water rates.[4]

The float regulator was later a common mechanism during the Industrial Revolution of the 18th century, when it was employed in the boiler of a steam engine and in domestic water distribution systems.[6]

Closed-loop system

This appears to be an early example of a closed-loop system in a mechanism. The clock functioned as long as there were metal balls in its magazine.[4]

Related

  • Water clock
  • Al-Jazari
  • Inventions in the Muslim world
  • Dar al-Magana
  • Dar al-Muwaqqit

References

  1. ^ Ibn al-Razzaz Al-Jazari (ed. 1974), The Book of Knowledge of Ingenious Mechanical Devices. Translated and annotated by Donald Routledge Hill, Dordrecht/D. Reidel.
  2. ^ Kerim Balci (14 June 2009). "A book on Muslim contributions to science provides solution to identity crisis". Today's Zaman. http://www.todayszaman.com/tz-web/detaylar.do?load=detay&link=177990. Retrieved 2009-06-19. 
  3. ^ Andrew Robinson (2007), The Story of Measurement: Useful Reference Encyclopedia Cubits to Megabytes, Thames & Hudson, ISBN 978-0500513675 
  4. ^ a b c The Machines of Al-Jazari and Taqi Al-Din, Foundation for Science Technology and Civilization
  5. ^ Ahmad Y Hassan; Donald Routledge Hill (1986), Islamic Technology: An Illustrated History, Cambridge University Press, p. 57-59, ISBN 0521263336 
  6. ^ Ahmad Y Hassan, Transfer Of Islamic Technology To The West, Part II: Transmission Of Islamic Engineering

External links

Useful Links