The Celts appear upon the field of history several centuries before the Christian era. Caesar's account of them leaves no doubt of the place which music held in their religion, education and national life. The minstrel was a prominent figure, ready at a moment's notice to perform the service of religion, patriotism or entertainment. There is a tradition of one King Blegywied ap Scifyllt, who reigned in Brittany about 160 B.C., who was a good musician and a player upon the harp. While we have no precise knowledge of the music they sang in the oldest times, it was very likely something like the following old Breton air, which is supposed to have come down from the Druids. It is full of a rude energy, making it impressive even to modern ears. By successive migrations of Angles, Danes and Northmen, the Celts were crowded into Wales, where they still remain. The harp has always been their principal instrument, and for many centuries a rude kind of violin called the crwth, of which there will be occasion to speak in connection with the violin, at a later period in this work. [Music illustration: OLD BRETON SONG. Da-ik mab gwenn Drouiz, o-re; Da-ik pe-tra fell d'id-de? pe-tra gan-inn-me d'id-de?-- Kan d'in euz aeur rann, Ken a ouf-enn bre-man;-- Heb rann ar Red heb-ken: An-Kou, tad ann an-ken; Ne-tra kent ne tra ken.-- Da-ik mab gwenn Drouiz, o-re; Da-ik pe-tra fell d'id-de? pe-tra gan-inn-me d'id-de?-- Kan d'in euz a zaou rann, Ken a ouf-enn bre-man.] According to the best authorities the bards were divided into three great classes. The first class was composed of the historians and antiquaries, who piqued themselves a little upon their sorcery, and who, upon occasion, took up the roles of diviners and prophets. The second class was composed of domestic bards, living in private houses, quite after the custom of ancient Greece. These we may suppose were chiefly devoted to the annals and glories of their wealthy patrons. The third class, the heraldic bards, was the most influential of all. They wrote the national annals. All these classes were poet-bards as well as musicians.