In Babylon a residence was set apart for the native philosophers called Chaldæans, who are chiefly devoted to the study of astronomy. Some, who are not approved of by the rest, profess to understand genethlialogy, or the casting of nativities. There is also a tribe of Chaldæans, who inhabit a district of Babylonia, in the neighbourhood of the Arabians, and of the sea called the Persian Sea.493 There are several classes of the Chaldæan astronomers. Some have the name of Orcheni, some Borsippeni, and many others, as if divided into sects, who disseminate different tenets on the same subjects. The mathematicians make mention of some individuals among them, as Cidenas, Naburianus, and Sudinus. Seleucus also of Seleuceia is a Chaldæan, and many other remarkable men.