Chinese music can be traced back as far as the third millennium B.C. Manuscripts and instruments from the early periods of its history are not extant, however, because in 212 B.C., Shih Huang-ti of the Ch'in dynasty caused all the books and instruments to be destroyed and the practice of music to be stopped. Certain outlines of ancient Chinese music have nevertheless been ascertained. Of primary significance is the fact that the music and philosophy of China have always been inseparably bound; musical theory and form have been invariably symbolic in nature and remarkably stable through the ages. Ancient Chinese hymns were slow and solemn and were accompanied by very large orchestras. Chamber music was also highly developed. Chinese opera originated in the 14th cent. as a serious and refined art.