Thus the ritual could not fail to become more and more of a mystery to all who did not belong to the Brahman caste. To its formulas, no less than to the sacrifice itself, control over Nature as well as the supernatural powers is attributed. Thus there are certain formulas for the obtainment of victory; by means of these, it is said, Indra constantly vanquished the demons. Again, we learn that, if the priest pronounces a formula for rain while mixing a certain offering, he causes the rain to stream down. Hence the formulas are regarded as having a kind of magical effect by exercising compulsion. Similar miraculous powers later came to be attached to penance and asceticism among the Brahmans, and to holiness among the Buddhists. The formulas of the Yajurveda have not, as a rule, the form of prayers addressed to the gods, but on the whole and characteristically consist of statements about the result of employing particular rites and mantras. Together with the corresponding ritual they furnish a complex mass of appliances ready to hand for the obtainment of material welfare in general as well as all sorts of special objects, such as cattle or a village. The presence of a priest capable of using the necessary forms correctly is of course always presupposed. The desires which several rites are meant to fulfil amount to nothing more than childish absurdity. Thus some of them aim at the obtainment of the year. Formulas to secure possession of the moon would have had equal practical value. Hand in hand with the elaboration of the sacrificial ceremonial went the growth and consolidation of the caste system, in which the Brahmans secured the social as well as the religious supremacy, and which has held India enchained for more than two thousand five hundred years. Not only do we find the four castes firmly established as the main divisions of Indian society in the Yajurveda, but, as one of the later books of the Vajasaneyi Samhita shows, most of the mixed castes known in later times are already found to exist. The social as well as the religious conditions of the Indian people, therefore, now wear an aspect essentially differing from those revealed to us in the hymns of the Rigveda.