Astronomical clock in the context of "Science and technology of the Song dynasty"

The incense clock (simplified Chinese: 香钟; traditional Chinese: 香鐘; pinyin: xiāngzhōng; Wade–Giles: hsiang-chung; lit. 'fragrance clock') is a timekeeping device that originated from China during the Song dynasty (960–1279) and spread to neighboring East Asian countries such as Japan and Korea. The clocks' bodies are effectively specialized censers that hold incense sticks or powdered incense that have been manufactured and calibrated to a known rate of combustion, used to measure minutes, hours, or days. The clock may also contain bells and gongs which act as strikers. Although the water clock and astronomical clock were known in China (example: Su Song), incense clocks were commonly used at homes and temples in dynastic times.

Su Song (Chinese: 蘇頌; Pe̍h-ōe-jī: So͘ Siōng, 1020–1101), courtesy name Zirong (Chinese: 子容; Pe̍h-ōe-jī: Chú-iông), was a Chinese polymathic scientist and statesman who lived during the Song dynasty (960–1279). He excelled in numerous fields including but not limited to mathematics, astronomy, cartography, geography, metallurgy, mechanical engineering, hydraulic engineering, poetry, and statesmanship.

Su Song was the engineer for a hydro-mechanical astronomical clock tower located in Kaifeng. It employed an early escapement mechanism. The escapement mechanism of Su's clock tower was invented by the Tang dynasty Buddhist monk Yi Xing and government official Liang Lingzan in 725 AD to operate a water-powered armillary sphere, however Su's armillary sphere was the first to utilize a mechanical clock drive. Su's clock tower also featured the oldest known endless power-transmitting chain drive, called the tian ti (天梯), or "celestial ladder", as depicted in his horological treatise. The clock tower had 133 different clock jacks to indicate and sound the hours. The clock was dismantled by the invading Jurchen army in 1127 AD, and although attempts were made to reassemble it, the tower was never successfully reinstated.

Exeter Cathedral, properly known as the Cathedral Church of Saint Peter in Exeter, is an Anglican cathedral, and the seat of the Bishop of Exeter, in the city of Exeter, Devon, in South West England. The present building was complete by about 1400 and has several notable features, including an early set of misericords, an astronomical clock and the longest uninterrupted medieval stone vaulted ceiling in the world.

The Zytglogge (Bernese German: [ˈtsiˌkːlɔkːə]; lit. 'time bell') is a landmark medieval tower in Bern, Switzerland. Built in the early 13th century, it has served the city as a guard tower, prison, clock tower, centre of urban life and civic memorial.

Despite the many redecorations and renovations it has undergone in its 800 years of existence, the Zytglogge is one of Bern's most recognisable symbols and the oldest monument of the city, and with its 15th-century astronomical clock, a major tourist attraction. It is a heritage site of national significance, and part of the Old City of Bern, a UNESCO World Heritage Site.

Yixing (Chinese: 一行; pinyin: Yīxíng; Wade–Giles: I-Hsing, 683–727) was a Buddhist monk of the Tang dynasty, recognized for his accomplishments as an astronomer, a reformer of the calendar system, a specialist in the Yijing (易經), and a distinguished Buddhist figure with expertise in Esoteric Buddhism.

In the realm of secular affairs, Yixing gained prominence for his reforms to the imperial calendar and his construction of a celestial globe featuring a liquid-driven escapement, the first in a long tradition of Chinese astronomical clockworks. Within Buddhist circles, he is particularly remembered for his contributions to the translation of the Mahāvairocana-sūtra and for authoring the authoritative commentary on that scripture, the Darijing shu 大日經疏 (T 1796). Due to his significant activities in both religious and secular spheres, a legendary portrayal of Yixing as a master astrologer and practitioner of astral magic developed during the late Tang period, leading to the attribution of several astrological works to him.

An armillary sphere (variations are known as spherical astrolabe, armilla, or armil) is a model of objects in the sky (on the celestial sphere), consisting of a spherical framework of rings, centered on Earth or the Sun, that represent lines of celestial longitude and latitude and other astronomically important features, such as the ecliptic. As such, it differs from a celestial globe, which is a smooth sphere whose principal purpose is to map the constellations. It was invented separately, in ancient China possibly as early as the 4th century BC and ancient Greece during the 3rd century BC, with later uses in the Islamic world and Medieval Europe.

With the Earth as center, an armillary sphere is known as Ptolemaic. With the Sun as center, it is known as Copernican.