We shall explain the sacrifice. Yajña, sacrifice, is an act by which we surrender something for the sake of the gods. Such an act must rest on a sacred authority (āgama), and serve for man's salvation (śreyo ऽ rtha). The nature of the gift is of less importance. It may be puroḍāśa, cake; karu, pulse; sāṃnāyya, mixed milk; paśu, an animal; soma, the juice of the Soma-plant, &c.; nay, the smallest offerings of butter, flour, and milk may serve for the purpose of a sacrifice. Yajña, yāga, yajana, and iṣṭi are considered as synonymes. The sacrifice is for the three colours or castes (varṇa), for Brāhmaṇas and Rājanyas, also for the Vaiśya. Though the sacrifice is meant for the three castes, here called varṇa, i.e. colour, the third caste, that of the Vaiśya or citizen, is mentioned by itself, while the two castes, the Brāhmaṇas and Rājanyas (the Kṣatriyas or nobles), are mentioned together. This is done because there are certain sacrifices (bahuyajamāna), performed by Brāhmaṇas and Rājanyas together, in which Vaiśyas take no part. In the Śāṅkhāyana-sūtras, I, 1, 3, also the Vaiśya is mentioned by himself. In Kātyāyana's Sūtras, however, no such distinction is made. and we read, I, 6, Brāhmaṇa-rājanya-vaiśyānāṃ śruteḥ. Women, if properly married, are allowed to participate in sacrifices, but no one is allowed to be accompanied by a Sūdrā woman, even though she be his wife. Properly a Brāhmaṇa should marry a wife of his own caste only. A Kṣatriya may marry a woman of his own or of the Brāhmaṇa caste. A Vaiśya's proper wife should be taken from his own caste. See, however, Manu III, 12 seq. The four castes, with the Śūdra as the fourth, are mentioned once in the Ṛg-veda, X, yo, 12. The opposition between Āryas and Śūdras occurs in the Atharva-veda, XIX, 62, &c., and in most of the Brāhmaṇas. In the Śatapatha Brāhmaṇa we read of the four castes, Brāhmaṇa, Rājanya, Vaiśya, and Śūdra, and we are told that none of them vomits the Soma. Kātyāyana excludes from the sacrifice the aṅgahīna, cripple, shaṇḍa, eunuch, and all aśrotriyas, persons ignorant of the Veda, which would bar, of course, the whole class of the Śūdras, but they are also specially excluded. Concessions, however, had to be made at an early time, for instance, in the case of the Rathakāra, who is admitted to the Agnyādhāna, &c. This name means chariot-maker, but Āpadeva, in his Mīmāṃsā-nyāya-prakāśa, remarks that, though rathakāra means a chariot-maker etymologically, it should be taken here as the name of a clan, namely that of the Saudhanvanas (MS. Mill 46, p. 13 b ). Deva, in his commentary on the Kātyāyana-sūtras, makes the same remark. See also Weber, Ind. Stud. X, 12 seq. These Saudhanvanas, often identified with the Ṛbhus, are evidently the followers of Bṛbu, mentioned RV. VI, 45, 31; 33, and wrongly called Bṛdhu in Manu X, 107; see M.M., Hist. of A.S.L., p. 494. In the Śāṅkhāyana-Śrauta-sūtras, XVI, 11, 11 (ed. Hillebrandt), he is rightly called Bṛbu. In later times Rathakāra is the name of a caste, and its members are supposed to be the offspring of a marriage between a Māhiṣya and a Karaṇī. A Māhiṣya is the son of a Kṣatriya and a Vaiśyā, a Karaṇī the daughter of a Vaiśya and a Śūdrā. Sudhanvan also is used in Manu X, 23, as the name of a caste, namely the offspring of fallen (vrātya) Vaiśyas. Another exception is made in favour of a Niṣādasthapati, a Niṣāda chieftain. If it meant a chieftain of Niṣādas, it might be meant for a Kṣatriya who happens to be a chieftain of Niṣādas. Here it is meant for a chieftain who is himself a Niṣāda, a native settler. He is admitted to the Gavedhuka sacrifice. Again, although, as a rule, the sacrificer must have finished his study of the Veda and be married, a sacrifice is mentioned which a Brahmacārin, a student, may perform. The case thus provided for is, yo brahmacārī striyam upeyāt, sa gardabham paśum ālabheta. As these sacrificers are not upanīta, and therefore without the sacred fires, their sacrifices have to be performed with ordinary fires, and the sacrificial offerings, the puroḍāśas, are not cooked in kapālas, jars, but on the earth, while the avadānas (cuttings), heart, tongue, &c., are sacrificed in water, and not in fire. The Niṣāda chieftain has to learn the necessary Vedic verses by heart, without having passed through a regular course of Vedic study. The same applies to women, who have to recite certain verses during the sacrifice. That certain women are admitted to the sacrifice, is distinctly stated by Kātyāyana, I, 1, 7, strī kāviśeṣāt. The sacrifice is prescribed by the three Vedas. In order to know the whole of the sacrifice, one Veda is not sufficient, still less one sākhā (recension) only. The sacrifice is conceived as a whole, and its members (aṅgas) are described in different parts of the three Vedas. By the Ṛg-veda, the Yajur-veda, the Sāma-veda (is the sacrifice prescribed). The Darśa-pūrṇamāsau, the new and full-moon sacrifices, are prescribed by the Ṛg-veda and the Yajur-veda. The Agnihotra is prescribed by the Yajur-veda. The Agniṣṭoma is prescribed by all. By saying all, the Atharva-veda is supposed to be included, at least according to one commentator. The Agniṣṭoma requires sixteen priests, the Paśu sacrifices six, the Cāturmāsyas five, the Darśa-pūrṇamāsas four. With the Ṛg-veda and Sāma-veda the performance takes place with a loud voice (uccaiḥ). Even lines of the Yajur-veda, if they are contained in the Ṛg-veda and Sāma-veda, would have to be pronounced with a loud voice. Certain mantras, however, are excepted, viz. the japa, abhimantraṇa, and anumantraṇa-mantras. With the Yajur-veda the performance takes place by murmuring (upāṃśu). This murmuring, upāṃśu, is described as a mere opus operatum, the words being repeated without voice and without thought. One may see the movements of the vocal organs in murmuring, but one should not hear them at a distance. If verses from the Ṛg-veda or Sāma-veda occur in the Yajur-veda, they also have to be murmured. See Kāty. I, 3, 10. With the exception of addresses, replies, choosing of priests (pravara), dialogues, and commands.