When did the Chinese calendar day start? What did the ancients use to calculate the time?

In the ancient calendar, it is common sense that a new day begins at 12: 30.

In the course of history, our ancestors invented and manufactured various timers at different times to meet the needs of social and economic development and people's life at that time. Among them, there are mainly standard watches, sundials, missing engravings, mechanical timers and so on.

sundial

Guibiao is the oldest timepiece in China. There are records about the use of Tugui in the ancient book Zhou Li, which shows that Guibiao has a long history. Standard gauges use the length of the sun's projection to judge time. It consists of two parts, one is the benchmark or stone pillar for measuring the shadow of the sun standing upright on the flat ground, which is called the table; One is a rigid plate used to measure the length of the surface shadow in the direction of due south and due north, which is called Gui. Since the shadow of the sun can be measured in units of length, it is logical to express the "yin" of time and the length of time in minutes and inches.

sundial

A sundial is also an instrument for measuring time by observing the shadow of the sun, which mainly determines the time or the number of minutes at that time according to the position of the shadow. Judging from the unearthed cultural relics, the sundial was used before the Han Dynasty, and it was always a common timer before the mechanical clock was introduced to China. The main part of a sundial consists of hands and facets. When the sun moves in the sky, the projection of the hand moves on the surface like the hands of a clock, which can indicate the time.

moment

Both the standard watch and the clepsydra use the shadow of the sun to calculate the time, but it will lose its function when it rains or it gets dark, so a kind of water clock that can time day and night is produced, which is the clepsydra. Leakage refers to the leakage of the pot; Carving means carving an arrow. The arrow is a ruler marked with a time scale. Missing carving is to calculate the time by observing the data displayed on the carved arrow in the pot by using the principle of balanced dripping. As a timer, cracks are more common than sundials. In ancient China, many literati and poets left many poetic chapters about missing prints. For example, Li He, a poet in the Tang Dynasty, said, "It's like adding seawater to a palace leak and dropping Nagato overnight." Su Shi in Song Dynasty: "When the moon is absent, people are quiet." Before mechanical clocks and watches were introduced to China, nicking was the most widely used timer in China.