It is impossible to estimate rightly Haydn’s service to music without taking into account one of his most striking and original characteristics--his use of simple tunes and folk songs. Much light has been thrown on this phase of his genius by the labors of a Croatian scholar, F. X. Kuhac, and the results of his work have been given to the English-speaking world by Mr. Hadow. As early as 1762, in his D-major symphony, composed at Eisenstadt, Haydn began to use folk songs as themes, and he continued to do so, in symphonies, quartets, divertimenti, cantatas, and sacred music, to the very end of his career. In this respect he was unique among composers of his day. No other contemporaneous writer thought it fitting or beautiful to work rustic tunes into the texture of his music. Mozart is witty with the ease of a man of the world, quite different from the naïve drollery of Haydn, whose humor, though perhaps a trifle light and shallow, is always mobile, fresh, and gay. It is pointed out, moreover, by the writers above mentioned that the shapes of Haydn’s melodic phrases are not those of the German, but of the Croatian folk song, and that the rhythms are correspondingly varied. Eisenstadt lies in the very centre of a Croatian colony, and Rohrau, Haydn’s birthplace, has also a Croatian name. Many of its inhabitants are Croatian, and a name, strikingly similar to Haydn’s was of frequent occurrence in that region. Add to this the fact that his music is saturated with tunes which have all the characteristics, both rhythmic and melodic, of the Croatian; that many tunes known to be of that origin are actually employed by him, and the presumption in favor of his Croatian inheritance is very strong. But Haydn’s speech, like that of every genius, was not only that of his race, but of the world. He had the heart of a rustic poet unspoiled by a decayed civilization. Like Wordsworth, he used the speech of a whole nation, and lived to work out all that was in him. Although almost entirely self-taught, he mastered every scientific principle of musical composition known at his time. He was able to compose for the people without pandering to what was vicious or ignorant in their taste. He identified himself absolutely with secular music, and gave it a status equal to the music of the church. He took the idea of the symphony and quartet, while it was yet rather formless and chaotic, floating in the musical consciousness of the period as salt floats in the ocean, drew it from the surrounding medium, and crystallized it into an art form.