In the fourteenth century appeared the device which played so large a part in the production of the Reformation hymns—that of adapting secular tunes to religious poems, and also making religious paraphrases of secular ditties. Praises of love, of out-door sport, even of wine, by a few simple alterations were made to express devotional sentiments. A good illustration of this practice is the recasting of the favorite folk-song, “Den liepsten Bulen den ich han,” into “Den liepsten Herren den ich han.” Much more common, however, was the transfer of melodies from profane poems to religious, a method which afterward became an important reliance for supplying the reformed congregations with hymn-tunes. Mixed songs, part Latin and part German, were at one time much in vogue. A celebrated example is the “In dulce jubilo Nu singet und seyt fro” of the fourteenth century, which has often been heard in the reformed churches down to a recent period. In the fifteenth century the popular religious song flourished with an affluence hardly surpassed even in the first two centuries of Protestantism. Still under the control of the Catholic doctrine and discipline, it nevertheless betokens a certain restlessness of mind; the native individualism of the German spirit is preparing to assert itself. The fifteenth was a century of stir and inquiry, full of premonitions of the upheaval soon to follow. The Revival of Learning began to shake Germany, as well as Southern and Western Europe, out of its superstition and intellectual subjection. The religious and political movements in Bohemia and Moravia, set in motion by the preaching and martyrdom of Hus, produced strong effect in Germany. Hus struck at some of the same abuses that aroused the wrath of Luther, notably the traffic in indulgences. The demand for the use of the vernacular in church worship was even more fundamental than the similar desire in Germany, and preceded rather than followed the movement toward reform. Hus was also a prototype of Luther in that he was virtually the founder of the Bohemian hymnody. He wrote hymns both in Latin and in Czech, and earnestly encouraged the use of vernacular songs by the people. The Utraquists published a song-book in the Czech language in 1501, and the Unitas Fratrum one, containing four hundred hymns, in 1505. These two antedated the first Lutheran hymn-book by about twenty years. The Bohemian reformers, like Luther after them, based their poetry upon the psalms, the ancient Latin hymns, and the old vernacular religious songs; they improved existing texts, and set new hymns in place of those that contained objectionable doctrinal features. Their tunes also were derived, like those of the German reformers, from older religious and secular melodies.