That all Celtic tribes were fond of it and cultivated it thoroughly we have the assertion of all ancient writers who spoke of them. According to Strabo, the Third order of Druids was composed of those whom he calls _Umnetai_. What were their instruments is not mentioned; and we can now form no opinion of their former musical taste from the rude melodies of the Armoricans, Welsh, and Scotch. From time immemorial the Irish Celts possessed the harp. Some authors have denied this; and from the fact that the harp was unknown to the Greeks and Romans, and that the Gauls of the time of Julius Caesar do not seem to have been acquainted with it, they conclude that it was not purely native to any of the British islands. But modern researches have proved that it was certainly used in Erin under the first successors of Ugaine Mor, who was monarch. --Ard-Righ--about the year 633 before Christ, according to the annals of the Four Masters. The story of Labhraid, which seems perfectly authentic, turns altogether on the perfection with which Craftine played on the harp. From that time, at least, the instrument became among the Celts of Ireland a perpetual source of melody. To judge of their proficiency in its use, it is enough to know to what degree of perfection they had raised it. Mr. Beauford, in his ingenious and learned treatise on the music of Ireland, as cultivated by its bards, creates genuine astonishment by the discoveries into which his researches have led him. The extraordinary attention which they paid to expression and effect brought about successive improvements in the harp, which at last made it far superior to the Grecian lyre. To make it capable of supporting the human voice in their symphonies, they filled up the intervals of the fifths and thirds in each scale, and increased the number of strings from eighteen to twenty-eight, retaining all the original chromatic tones, but reducing the capacity of the instrument; for, instead of commencing in the lower E in the bass, it commenced in C, a sixth above, and terminated in G in the octave below; and, in consequence, the instrument became much more melodious and capable of accompanying the human voice. Malachi O'Morgair, Archbishop of Armagh, introduced other improvements in it in the twelfth century. Finally, in later times, its capacity was increased from twenty-eight strings to thirty-three, in which state it still remains.