Sundial in front of the Forbidden City
The sundial, also known as the "day gauge", is an ancient timekeeping instrument that uses the shadow of the sun to measure the time. "Sundial" means "shadow of the sun", so a sundial is a tool to time it by observing the position of the straight rod's shadow under the sun.
Humans have been using sundials for a long time, as early as 6,000 years ago in ancient Babylon. The Sui Dynasty, which first appeared in ancient China since 574 AD, records in the Book of Sui and Astronomical Chronicles: "In the fourteenth year of the Kai Emperor, Sima Yuan of Yanzhou was engraved on the sun. Filled with a short shadow flat instrument, all clothed twelve, standing a table, with the sun shadow pointed to the chen, in order to detect the section of water leakage. However, it is rarely used by future generations because of its shortcomings of "not being sophisticated".
Copper-gilded flat sundial
Sundials used in China before the Qing Dynasty belonged to the equatorial sundial, mostly of stone, carved on a circular stone plate, with a vertical metal dial needle and a vertical plate in the middle. The dial is placed obliquely on a white jade constellation, sitting in a north-south direction, using the projection of the sun and the change of the length of the sun's shadow formed by the rotation of the earth and the different directions to determine the time. There are also symbols of imperial power used in front of the palace, generally juxtaposed with Jialiang, symbolizing the unity of heaven and earth and the eternal solidity of the country.
John Tang handmade sundial Takumoto
This is Tang John's new legal system of weekday sundial Tuoben, for Luo Zhenyutuo to give Wu Baochu, there is a Luo shi inscription cloud: "Tang John handmade sundial, made by Qingyu." Yi Wei Xia was born in the Yan clan of Wu Zhong. In the middle of the winter, hand-extended a piece of paper Bong Gongqing play, Luo Zhenyu inscription, when the same Ke Jingu.
In the 17th century, foreign missionaries introduced the newly invented horizon sundial from Europe to China, and the new Western sundial was recognized and used by the Qing Palace because of its small and exquisite shape and convenient carrying. The first case of a new law of flat sundials entering the Qing Palace was on July 9 of the first year of Shunzhi, by the German missionary John Tang to the regent Dol roll and the Shunzhi Emperor, and later developed by the Three Dynasties of Kang Yonggan, made by the palace office for the use of the imperial family, with special emphasis on localization.
Qianlong Imperial coral red and gold color dry branch sundial
The sundial is shaped like a pot, bearing the head of the beast with three legs, and the shape is small and unique. The whole instrument is made of coral red color, and the effect of imitation carving paint on the outer wall is enough to confuse the truth. Folded along the wide flat, equally divided into twenty-four equal parts, in gold color to write the heavenly dry earth branch and the words "dry" and "kun". There is a small hole under the "son" and "noon" positions, which are tied with silver wire, that is, dial needles. The concave hemisphere is the dial disk, on which four groups of time lines are painted in gold, the middle two groups are divided into forty-eight grids, and the center writes out the twelve hours of the day" in the center: "卯正, 辰初, 辰正, 巳初, 巳正, 巳正, Noon, 未初, 未正, 申初, 申正, 酉初", 卯正 is six o'clock in the morning, unitary beginning is five o'clock in the afternoon, each hour is equivalent to one hour, representing the time of the day.
When using the new method of weekday sundial, first use the compass to determine the north and south, for example, this product needs to "noon" to the south position, "son" to the north position, balanced placed under the sun, when the sun reaches the dial needle, it casts a sun shadow on the dial, and overlaps with the corresponding time line, that is, the desired moment. The so-called new law means that the production of this sundial adopts the design principle of the popular level sundial in Europe. In terms of scale, the traditional Chinese method of one hundred times a day and equal scale is changed to ninety-six minutes a day, and the time line is marked in the form of unequal divisions. Because this product is hemispherical, only forty-eight channels are depicted in the concave surface. Compared with the horizon sundial originally introduced to China in Europe, the construction principle of this sundial is more convenient and simple, and the practicality is strong, although it is slightly inferior to western manufacturers in terms of precision, but it is enough to understand daily life.
Qingqianlong Royal copper gilded inlaid enamel level sundial
The sundial instrument is made by the Qinggong Manufacturing Office, and the four ends bear the screw foot that can rotate and adjust the height, which is used to adjust the horizontal pipe of the sundial for the level of the horizon and determine the level. The four-legged top surface is inlaid with the words "East, West, South and North" in the blue enamel gold color book, which matches the compass of the sundial to determine the direction. The dial is in a circular arc, decorated with white enamel on the time plate, and painted with twelve hours of time, and the top of the dial is equipped with a movable folding straight watch for easy carrying. The double-sided engraved curly leaf floral pattern of the sundial copper gilded parts is a rare work of Qing Palace scientific instruments with a Western Rococo art style.
Jasper rosewood palace sundial
The clear record of China's equatorial sundial first appeared in the Southern Song Dynasty Zeng Minxing's "Awakening Magazine". Equatorial sundials are fixed towards the north and south poles according to the latitude of the place of use, and the dials are parallel to the equatorial plane. When the sun shines on the sundial, the shadow of the dial needle is cast on the dial. The sun moves from east to west, and the dial shadow slowly moves from west to east. Sundials are placed in front of the main hall of the Forbidden City, symbolizing that the emperor has the highest power to grant time to all the peoples of the world.
Copper gilt inlaid enamel with plumbed horizon sundial