Tacitus, Ann. xiv. 30; Dio Cass. lxii. 6.
800. Appian, Celtica, 8; Livy, xxi. 28, xxxviii. 17, x. 26.
801. Livy, v. 38, vii. 23; Polybius, ii. 29. Cf. Watteville, Le cri de guerre chez les differents peuples, Paris, 1889.
802. Livy, v. 38.
803. Appian, vi. 53; Muret et Chabouillet, Catalogue des monnaies gauloises, 6033 f., 6941 f.
804. Diod. v. 31; Justin, xxvi. 2, 4; Cicero, de Div. ii. 36, 76; Tac. Ann. xiv. 30; Strabo, iii. 3. 6.
805. Dio Cass. lxii. 6.
806. Reinach, Catal. Sommaire, 31; Pseudo-Plutarch, de Fluviis, vi. 4; Mirab. Auscult. 86.
807. Strabo, iv. 4. 6.
808. Justin, xxiv, 4; Cicero, de Div. i. 15. 26. (Cf. the two magic crows which announced the coming of Cúchulainn to the other world (D'Arbois, v. 203); Irish Nennius, 145; O'Curry, MC ii. 224; cf. for a Welsh instance, Skene, i. 433.)
809. Joyce, SH i. 229; O'Curry, MC ii. 224, MS Mat. 284.
810. IT i. 129; Livy, v. 34; Loth, RC xvi. 314. The Irish for consulting a lot is crann-chur, "the act of casting wood."
811. Cæsar, vi. 14.
812. O'Curry, MC ii. 46, 224; Stokes, Three Irish Homilies, 103.
813. Cormac, 94. Fionn's divination by chewing his thumb is called Imbas Forosnai (RC xxv. 347).
814. Antient Laws of Ireland, i. 45.
815. Hyde, Lit. Hist. of Ireland, 241.
816. Justin, xliii. 5.
817. O'Grady, ii. 362; Giraldus, Descr. Camb. i. 11.
818. Pennant, Tour in Scotland, i. 311; Martin, 111.
819. Richardson, Folly of Pilgrimages, 70.
820. Tertullian, de Anima, 57; Coll. de Reb. Hib. iii. 334.
821. Campbell, Superstitions, 263; Curtin, Tales, 84.
822. Lucan, ed. Usener, 33.
823. See examples in O'Curry, MS Mat. 383 f.
824. Miss Hull, 19, 20, 23.
825. LU 55.
826. RC xii. 98, xxi. 156, xxii. 61.
827. RC xv. 432; Annals of the Four Masters, A.M. 2530; Campbell, WHT iv. 298.
828. See "Adamnan's Second Vision." RC xii. 441.
Tabu
The Irish geis, pl. geasa, which may be rendered by Tabu, had two senses. It meant something which must not be done for fear of disastrous consequences, and also an obligation to do something commanded by another.
As a tabu the geis had a large place in Irish life, and was probably known to other branches of the Celts.829 It followed the general course of tabu wherever found. Sometimes it was imposed before birth, or it was hereditary, or connected with totemism. Legends, however, often arose giving a different explanation to geasa, long after the customs in which they originated had been forgotten. It was one of Diarmaid's geasa not to hunt the boar of Ben Gulban, and this was probably totemic in origin. But legend told how his father killed a child, the corpse being changed into a boar by the child's father, who said its span of life would be the same as Diarmaid's, and that he would be slain by it. Oengus put geasa on Diarmaid not to hunt it, but at Fionn's desire he broke these, and was killed.830 Other geasa—those of Cúchulainn not to eat dog's flesh, and of Conaire never to chase birds—also point to totemism.
In some cases geasa were based on ideas of right and wrong, honour or dishonour, or were intended to cause avoidance of unlucky days. Others are unintelligible to us. The largest number of geasa concerned kings and chiefs, and are described, along with their corresponding privileges, in the Book of Rights. Some of the geasa of the king of Connaught were not to go to an assembly of women at Leaghair, not to sit in autumn on the sepulchral mound of the wife of Maine, not to go in a grey-speckled garment on a grey-speckled horse to the heath of Cruachan, and the like.831 The meaning of these is obscure, but other examples are more obvious and show that all alike corresponded to the tabus applying to kings in primitive societies, who are often magicians, priests, or even divine representatives. On them the welfare of the tribe and the making of rain or sunshine, and the processes of growth depend. They must therefore be careful of their actions, and hence they are hedged about with tabus which, however unmeaning, have a direct connection with their powers. Out of such conceptions the Irish kingly geasa arose. Their observance made the earth fruitful, produced abundance and prosperity, and kept both the king and his land from misfortune. In later times these were supposed to be dependent on the "goodness" or the reverse of the king, but this was a departure from the older idea, which is clearly stated in the Book
