The Clepsydra
漏壶
The clepsydra is an instrument for time calculation in anaent China.The ancient people, upon finding that water in a pottery often leaked out drop by drop, made a pottery kettle with a small hole. Water filling the kettle would leak out through the hole, and another kettle was used to collect the leaking water. A marked arrow, like the dial of todays watch, was placed inside the second kettle through the hole of the kettle lid, floating on top of the water with the support from a bamboo flake or a wooden plate. The keftle was known as an “arrow kettle”.As the water level increased, the arrow also moved upwards,and people could know the exact time through looking at the marks on the arrow.
漏壶是中国古代的一种计时工具。最初，人们发现陶器中的水会从裂缝中一滴一滴地漏出来，于是专门制造出一种留有小孔的漏壶，把水注入漏壶内，水便从壶孔中流出来，另外再用一个容器收集漏下来的水。在这个容器内有一根刻有标记的箭杆，相当于现代钟表上显示时刻的钟面，用一个竹片或木块托着箭杆浮在水面上，容器盖的中心开一个小孔，箭杆从盖孔中穿出，这个容器叫做“箭壶”。随着箭壶内收集的水逐渐增多，箭杆也慢慢地往上浮，古人从盖孔处看箭杆上的标记，就能知道具体的时刻。
As the clepsydra was passed on from generation to generation, it gradual-ly evolved into a set of four pots. These are placed in order on a four-level wood-en stand, the one on the highest level called the Sun Pot, and below.the Moon Pot, Sfar Pot and Water-receiving Pot, respectively. The Sun Pot, Moon Pot and Star Pot all have an opening at the bottom for water to drop, and the Water-receiving Pot has a gauge inside. The water drops from the Sun Pot into the Moon Pot and then into the Star Pot and at last into the Water-receiving Pot. As more and more water drops into the Wa-ter-receiving Pot, the gauge gradually in-creases with the buoyancy of water. And thus people could tell the time through the scale above the water. The more levels the clepsydra has, the more accurate it is to measure time. Now, the four-level clepsydras of the Yuan and Qing dynasties are preserved respectively in the Muse-um of Chinese History and the Palace Museum in Beijing.
漏壶历代相传，由单只逐渐发展成为后来四只一套的漏壶。人们把四只漏壶依次放在一个四级木架上，上面的一只叫日壶，下面的三只分别叫月壶、星壶、授水壶。日壶j月壶、星壶的下面各有一个滴水的铜嘴，授水壶内有一个标尺。水从日壶滴人月壶，再到星壶，最后滴入授水壶。授水壶内的水越来越多，标尺受到水的浮力作用逐渐上升，人们通过标尺浮出水面的刻度，就可以知道时间了。漏壶的级数越多，计时就越准确。现在，在北京的中国历史博物馆和故宫博物院里还分别保存着元代和清代的四级漏壶，供人们参观。
The copper clepsydra is the crystallization of ancient Chinese wisdom and cre-ativeness. It not only tells us how ancient Chinese measured time, but also pro-vides precious materials on the development of science and technology in ancient China.
漏壶是中国古人聪明才智的结晶，它不仅告诉了我们古人计时的方法，也留下了中国古代科学技术发晨的宝贵资料。