Observations of Comets from BC 611 to AD 1640

Long before their western counterparts, Chinese astronomers developed remarkably accurate methods for making their measurements, recording detailed observations since ancient times. Of particular interest to John Williams (1797-1874), assistant secretary to the Royal Astronomical Society, were Chinese observations of comets. Noting that previous translations of these records had been incomplete, Williams sought to produce a fuller catalogue. The present work, published in 1871, presents Chinese comet observations between 611 BCE and 1640 CE, using the encyclopaedia of Ma Duanlin and the great historical Shiji as major references. Williams provides useful context in his introductory remarks, mentioning the tests by which the accuracy of the Chinese records can be verified. He also includes chronological tables and a Chinese celestial atlas, enabling comparison between the Chinese and Western systems for dates and stars respectively.