The music of the other composers of the fourth period is but a reflection of that of Lasso, who was fully as great a genius as Palestrina. He had a perfect mastery of the whole science of counterpoint as it had been developed by the masters of the first two periods. He was equally a master of the simpler style which had gradually been asserting itself. He used these styles and their combinations according to the character of the text to which he was writing music. Some of his masses are Gothic in their wonderful tracery of intertwining parts. His famous "Penitential Psalms" surprise, move and conquer us by their beautiful, pathetic simplicity. The notable fact about all his music, and about that of his contemporaries, is the plain manifestation through it all of an absolute mastery of contrapuntal science and a settled employment of it for their own purposes of expression. And here arises the question, what kind of expression? The music of Lasso, and some of that written by other composers of this period, shows that musicians had at last begun to lay hold of the real purpose of their art. Their music shows that they aimed at expression of themselves. They began to praise God personally, and musical science became in truth what it had been only in appearance so far as the composers were concerned--a real, earnest _Gloria Tibi_. It is this which vitalizes Lasso's music and makes it acceptable to-day. We have now reached the time after which the brilliancy of the Netherlands school speedily disappeared. The march of musical progress was transferred to Italy, where the seed sown by Willaert and De Rore in Venice was producing splendid fruit. Indeed the mission of the Netherlands school was at an end. It had given its life blood to the perfection of musical science and had completed its labors and achieved its loftiest glory by indicating the emotional power of music. We have seen that each of the four periods was marked by a step in the advancement of art, thus: First period: Perfection of Contrapuntal Technics. Second period: Attempts at Euphony. Third period: Development of Tone-painting. Fourth period: Counterpoint made subservient to emotional expression.