1. the WATER CLOCK KYOTO University of Education Shigenobu KOBAYASHI

2. This is the WATER CLOCK It is the story 1400 years ago. This is the WATER CLOCK model.

3. Contents 1.Why was the WATER CLOCK produced? 2.The history about the WATER CLOCK in Japan. 3.What is the WATER CLOCK(1)? 4.The pictures of the WATER CLOCK. 5.What is the WATER CLOCK(2)? 6.Why is it proportionally? 7.Relation between the WATER CLOCK and education.

4. Why was the WATER CLOCK produced? A long time ago Ancient society progressed It is managed for 24 hours Symbol of power to govern time Go to next page DAYNIGHTLONG SUNDIALO.K.N.G.O.K. SANDGLASSO.K. N.G. WATER CLOCKO.K.

5. The history about the WATER CLOCK in Japan. The water clock was in a capital. YearCapitalWater Clock 660AsukaIn Asuka 667OhmiIn Ohmi 672Nara The water clock has not been discovered. 794Kyoto The water clock has not been discovered. Kyoto Ohmi Asuka Osaka

6. What is the WATER CLOCK(1)?? Parts 1.Water 2.Water tank 3.Siphon tube (This tube can carry water little by little. ) 4.Doll 5.Stick(The doll has this stick with scale.) 1,2 4 3 5

7. The pictures of WATER CLOCK. Station Ohmi Shrine

8. In Ohmi Stick The 4 tanks made from stones is placed in the shape of stairs.

9. In Asuka Whole view The ruins of Mizuoti The water clock was here Logs (This is the marks of the pillar of the building)

10. Immediately after unearthing Model The water clock

11. What is the WATER CLOCK(2)?? Usage 1.4 water tanks is full of water. 2.Water is carried to next water tank by Siphon tube. 3. An officer supplies water to the top tank. 4. Water goes into a last tank in proportion to time. ( Next page) 5.The stick which a doll has floats. 6. An officer tells time. 7. An officer sounds a bell

12. Why is it proportionally? Key Point is the Water level !! By placing some tanks, the water level of the 3 rd tank is kept constant. So, water moves in proportion to time by using siphon tube !! (We can see) Average rate of change about water level Time Function (proportionality)

13. Relation between the WATER CLOCK and education. Theme : The WATER CLOCK : inclosing subject History : History of Kyoto Changes of a capital An old time system Science : a Water level a Water pressure Mathematics : Time Function (proportionality)

14. Thank you