centuries the inevitable comparison with every other form of melody, religious and secular, and there is reason to believe that they will continue to sustain all possible rivalry, until they at last outlive every other form of music now existing. No one can obtain any proper conception of this magnificent Plain Song system from the examples which one ordinarily hears in Catholic churches, for only a minute part of it is commonly employed at the present day. Only in certain convents and a few churches where monastic ideas prevail, and where priests and choristers are enthusiastic students of the ancient liturgic song, can we hear musical performances which afford us a revelation of the true affluence of this mediaeval treasure. What we customarily hear is only the simpler intonings of the priest at his ministrations, and the eight “psalm tones” sung alternately by priest and choir. These “psalm tones” or “Gregorian tones” are plain melodic formulas, with variable endings, and are appointed to be sung to the Latin psalms and canticles. When properly delivered, and supported by an organist who knows the secret of accompanying them, they are exceedingly beautiful. They are but a hint, however, of the rich store of melodies, some of them very elaborate and highly organized, which the chantbooks contain, and which are known only to special students. To this great compendium belong the chants anciently assigned to those portions of the liturgy which are now usually sung in modern settings,—the Kyrie, Gloria, Credo, Sanctus, Benedictus, Agnus Dei, and the variable portions of the Mass, such as the Introits, Graduals, Prefaces, Offertories, Sequences, etc., besides the hymns sung at Vespers and the other canonical hours. Few have ever explored the bulky volumes which contain this unique bequest of the Middle Age; but one who has even made a beginning of such study, or who has heard the florid chants worthily performed in the traditional style, can easily understand the enthusiasm which these strains arouse in the minds of those who love to penetrate to the innermost shrines of Catholic devotional expression. The theory and practice of the liturgic chant is a science of large dimensions and much difficulty. In the course of centuries a vast store of chant melodies has been accumulated, and in the nature of the case many variants of the older melodies—those composed before the development of a precise system of notation—have arisen, so that the verification of texts, comparison of authorities, and the application of methods of rendering to the needs of the complex ceremonial make this subject a very important branch of liturgical science.