Elephant clock

 

Ismail al-Jazari:-

A Muslim polymath from  Jazira in Mesopotamia. He was a scholar,engineer,artist,mathe,mathematician etc.He is best known for writing The Book of Knowledge of Ingenious Mechanical Devices. In this book, he has written or given many tricks related to  engineering.

In this book in 1206, where he described 100 mechanical devices, some 80 of which are trick vessels of various kinds, along with instructions on how to construct them. He is credited with the inventions of the flush toilet and the elephant clock.

We are going to discuss about elephant clock.

1.It consisted a weight powered water clock in the form of an Asian elephant. The various elements of the clock are in the housing (howdah) on top of the elephant.

2.The timing mechanism is based on a water-filled basin hidden inside the elephant.

3.In the bucket is a deep bowl floating in the water, but with a small hole in the centre. 

4.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.

5. 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. 

6.Next, the snake tips back. The cycle then repeats, as long as balls remain in the upper reservoir to power the emptying of the bow.

                                                                                                content source:wikipedia.org

Su-song

A chinese polymathic scientist, excellent in various subjects like mathemetics,astronomy,cartography,geogrphy,horology,pharmacology,mineralogy,metallurgy,zoology,botany,mechanical engineering,hydraulic engineering,civil engineering,architecture,invention,art,poetry,philosphy,antiquities. and stateman during Song dynasty. He made clock tower. 

In this tower, 

1. we can see specific building with turret clock and have one or more clock faces.

 2.Many other clock towers are freestanding structures but they can also adjoin or located on the top of another building.other building have clock faces but they have some other functions. 

3.clock owers are common sight in many parts with some iconic buildings. 

4.The mechanism inside the tower is known as a turret clock. 

It often marks the hour (and sometimes segments of an hour) by sounding large bells or chimes, sometimes playing simple musical phrases or tunes. Some clock towers were previously built as Bell towers and then had clocks added to them. As these structures fulfil the definition of a tower they can be considered to be clock towers.

history of computer in Nepal

 We have been using computer since many years.In Nepal, if we look, it was started from 2028 B.S. This was the starting stage  of computer in Nepal. The government of Nepal had to count population of 2028 B.S. For this ,the government brought IBM 1401 series computer on lease i.e. Rs 125000 per month.This computer was helpful and completed the census in 1 year 7 months and 15 days.

                                                                                      Later on, for next census of 2038 B.S., another computer named ICL 2950 was brought. It was too much expensive to bring this so the government could not afford and it was funded by UNDP and UNFA at 2 million US dollar. Then 2039 B.S onwards many micro computers (Apple,sirius,vector etc) were brought in Nepal.

                         During that period we had no man-power to use to operate computers. For this many trainers were imported ;especially from UK;and given tariinig to Nepalese people.Nepal gover,nment set up an EDP (Electronic Data Processing) as training center.Later it was renamed to NCC(National Computer Center). 

                               Now-a-days, we have many training institutes across the Nepal. They are providing computer education as well as training to students.

                                                                   Not only that much,Nepal governement 's initiation is also praise-worthy in the field of IT.

Antikythera mechanical computer

 It is an acient Greek computer ,believed as first analog computer powered by Orrey. 

It was used to predict astronomical psoition and calendar in advance.

As the history says it was retrieved from the sea from a seawreck.

It was believed that it was invented by Greek scientist in 87 B.C.

Features:-

1. It contains two faces front and rear face.

   Front face:-

          ->The front face has two concentric scales.

          ->The first scale marks the Greek sign of the Zodiac.

         ->The outer scale which is moveable ring that fits the flush with the surface and runs in a channel, marked off with what appear to be days.

        ->The outer layer has been presumed to represent 365 days;however, recent reseearch shows soe evidence that it is mostly likely to divide into 354 intervals.

         ->If onesubscribes to the 354 days evidence, then most likely the interpretation is that ring is a manifestation of a 354 day lunar calendar.

      

photo credit:wikipedia.org

        ->The lunar calendar purpose was t serve daya to day indicator of successive lunations and have assisted with the interpretation of lunar  phase pointer and metonic and saros dials. 

   Rear face:

          ->This face contains five dials: two large displays the Metonic and Saros and three small indicators,called Olympiad dial.

          ->the metonic dial is the main upper dial on the rear of the mechanism. the metonic cycle defined in Physics is very closed to 19 tropical years. I

          ->It is therefore a convenient interval over which to convert between lunar and solar calendars.

        ->The metonic dial covers 235 months in five rotations of the dial.the pointer points to the synodic month,counted from new moon to new moon.

Turing Tumble

 This device was made by Alan Turing.It's a game that  demonstrates logic gates via mechanical computer. It's a teaching device primarily used for teaching on logical concept of computer programming.

It contains following major parts.

• Ball drops. The standard version uses two ramps which store a given number of balls. A switch at the bottom of the board triggers the release of the initial ball (typically blue), from the top left of the panel. The second ramp, on the right, contains red balls.
• Ramps and crossovers. The green ramp allows the balls to run down it one way and release it in only that direction, whereas the orange crossover lets balls traverse it to either side both ways, i.e. from right to left and vice versa.
• Interceptors. This black piece stops a ball.
• Bits. This is a one-bit storage: it changes direction when a ball rolls through, such that the next ball goes to the other side.
• Gear and gear bits. Gear bits are exactly like regular bits, but they can be connected to gears. The gears allow for linking state changes, thus integrally adding extra (abstract) power.

UNIVAC

 UNIVAC(UNIVersal Automatic Computer.) was made by J.P. Eckert  and J.W. Mauchly in 1961AD.

• It consisted of tape drives which could use either the old UNIVAC I metal tapes or the new PET film tapes, and some circuits that were transistorized (although it was still a vacuum tube computer)

  
  
  
  
  
  photo credit:wikipedia.org

• Its purpose was mostly for calculations of census or defense department.

• Its features are as follows:

1. It was 8 feet high,15 feet long and weighed about 15 tons.

2. The UNIVAC 90/60 Series first ran with Univac developed OS/9,

3. The UNIVAC Solid State was a 2-address, decimal computer.

EDSAC

 EDVAC(electronic delay storage automatic computer), was constructed by Maurice Wilkes and his team at the University of Cambridge Mathematical Laboratory in England.

•  It used mercury delay lines for memory, and derated vacuum tubes for logic. Input was via five-hole punched tape and output was via a teleprinter.

• It has various purposes such as to solve a differential equation relating to gene frequencies, was used to gather numerical evidence about solutions to elliptic curves, etc

Additionally it has the following features:

1. The EDSAC's memory consisted of 1024 locations, though only 512 locations were initially implemented.

2. only 17 bits were used.

   
   picture credit:pinterest.com

3. This device was the world's first practical stored program electronic computer.

4. It uses a binary number system.

5. Both input and output used paper type.

6. This machine was used to calculate a table of squares and a list of prime numbers.