When we come to the dawn of the Christian period in Ireland and in Scotland, we see Patrick and Columba, the first and greatest of the Gaelic missionaries, very extensively practising exorcism; and there is every reason to believe (though the data available on this point are somewhat unsatisfactory) that their wide practice of exorcism was quite as much a Christian adaptation of pre-Christian Celtic exorcism, such as the Druids practised, as it was a continuation of New Testament tradition. We may now present certain of the data which tend to verify this supposition, and by means of them we shall be led to realize how fundamentally such an animistic practice as exorcism must have shaped the Fairy-Faith of the Celts, both before and after the coming of Christianity. 'Once upon a time,' so the tale runs about Patrick, 'his foster-mother went to milk the cow. He also went with her to drink a draught of new milk. Then the cow goes mad in the byre and killed five other kine: a demon, namely, entered her. There was great sadness on his foster-mother, and she told him to bring the kine back to life. Then he brought the kine to life, so that they were whole, and he cured the mad one. So God's name and Patrick's were magnified thereby.'[188] On another occasion, when demons came to Ireland in the form of black birds, quite after the manner of the Irish belief that fairies assume the form of crows (see pp. 302-5), the Celtic ire of Patrick was so aroused in trying to exorcize them out of the country that he threw his bell at them with such violence that it was cracked, and then he wept:--'Now at the end of those forty days and forty nights' [of Patrick's long fast on the summit of Cruachan Aigle or Croagh Patrick, Ireland's Holy Mountain] 'the mountain was filled with black birds, so that he knew not heaven or earth. He sang maledictive psalms at them. They left him not because of this. Then his anger grew against them. He strikes his bell at them, so that the men of Ireland heard its voice, and he flung it at them, so that a gap broke out of it, and that [bell] is "Brigit's Gapling". Then Patrick weeps till his face and his chasuble in front of him were wet. No demon came to the land of Erin after that till the end of seven years and seven months and seven days and seven nights. Then the angel went to console Patrick and cleansed the chasuble, and brought white birds round the Rick, and they used to sing sweet melodies for him.'[188] In Adamnan's _Life of S. Columba_ it is said that 'according to custom', which in all probability was established in pagan times by the Druids and then maintained by their Christian descendants, it was usual to exorcize even a milk vessel before milking, and the milk in it afterwards.[189] Thus Adamnan tells us that one day a youth, Columban by name, when he had finished milking, went to the door of St. Columba's cell carrying the pail full of new milk that, _according to custom_, the saint might exorcize it. When the