etymological, and astronomical inquiries. As the people in the land of the Ganges had ceased to understand Sanskrit in the sixth century _B.C._, while the Brahmans were compelled to preserve it for the Vedas and the Brahmanas, and as a learned and theological language, it became necessary to learn it from teachers. The sutras of the Buddhists speak of a grammar of Indra, which is also mentioned by the Chinese Hiuan-Thsang as the earliest Indian grammar; from the fourth century B.C. we have the grammatical rules of Panini remaining, which, based on the previous Çrauta-sutras, present us with a complete grammatical system, provided with an artificial terminology.[360] The desire to offer sacrifices to the gods at the correct and acceptable time did not permit the Brahmans entirely to neglect the observation of the heavens. Their attention was directed principally to the moon, to the courses of the planets they paid no particular regard. According to the advance of the moon in the heavens they distinguished twenty-seven, and at a later period twenty-eight stations in the sky (_nakshatra_). "The moon," we are told, "follows the course of the Nakshatras." The year of the Indians was divided into twelve months of thirty days; the month was divided into two halves of fifteen days each, and the day into 30 hours (_muhurta_). In order to bring this year of 360 days into harmony with the natural time, the Brahmans established a quinquennial cycle of 1860 lunar days. Three years had 12 months of 30 lunar days; the third and fifth year of the cycle had thirteen months of the same number of days. The Brahmans do not seem to have perceived that by this arrangement the cycle contained almost four days in excess of the astronomical time; and indeed they were not very skilful astronomers. Twelve quinquennial cycles were united into a greater period (_yuga_) of sixty years.[361] It was an old belief of the Indians that sacrifices and important affairs in domestic and family life should only be engaged in when the position of the sky was favourable--when the moon was waxing, or the sun moving to the north. At a later time it was also believed that the constellation, under which a child saw the light, was of good or evil influence on his fortunes. Charms are preserved, which are supposed to avert evil influences of this kind.[362] Some time after the seventh century the Brahmans began to foretell the fortunes of children from the position of the stars of their parents, to look for the marks of good and bad fortune on the human body as well as in the sky, and to question the stars about the favourable hours for the transactions or festivals of the house, and the labours of the field, voyages and travels. Though the book of the law declares astrology to be a wicked occupation,[363] it was carried on to a considerable extent in the fifth and fourth centuries. But this astrological superstition has nevertheless remained without effect in advancing the astronomy of the