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.