The instrument was known in the occident long before King Pepin received one as a present from Emperor Constantine Copronymos in 757 A. D. A Greek description of an organ belonging to Julian the Apostate (fourth century) and others mentioned by Cassiodorus and St. Augustine furnish valuable details. These instruments usually consisted of from eight to fifteen pipes (one to two octaves of the diatonic scale) which were constructed in the same manner as the flue pipes of modern organs. Throughout the ninth century organs were assiduously manufactured by monks, especially in France and Germany, and their compass was made to coincide with the middle range of the human voice (c to c´) so as to be used in connection with vocal instruction. The names of the tones were inscribed on the 'keys,’ which were small wooden plates in _vertical_ position. The player was obliged to pull this shutter away to allow the wind to enter the pipes, which would sound continuously till shut. By 980 there existed organs of considerable size, such as the famous one at Winchester, consisting of 400 pipes and two keyboards, requiring two players. A special form of notation, known as tablature, grew up for organ playing which coincides in general with our modern staff notation. * * * * * The above will, we believe, suffice to give a clear account of the musical activities of the period which we have called the Age of Plain-song. Among music-loving people in general there is a lack of interest in plain-song, due partly to religious reasons, but chiefly born of a tendency to regard it as a dry and spiritless formula, an insipid sort of recitative designed to lend solemnity to devotional exercises. Complete lack of sympathy and imagination could alone excuse such an impression in the minds of those who have ever had the opportunity of hearing it sung in a sincere and reverent spirit. Unlike the pedantic, mathematical art that music came to be in the middle ages, plain-song was preëminently a form of emotional expression. Further, it was the expression of emotions most poignant and profound. It came from the hearts of men who were conscious actors in a gigantic drama. The inexpressible tortures of eternal fire, the ecstatic wonders of a golden heaven, the ineffable mystery of the Godhead, the awful panoply of the Judgment, the wrath and agony of a wronged and insulted Deity who yet offered Himself as a bloody holocaust for the sins of men--all the esoteric spiritual symbols of Christianity had for these early believers a real and literal significance. To them was vouchsafed the simple faith, the naïve wonder of childhood. Their souls were possessed with a great awe, with an intense longing, with profound humility and passionate remorse, with fiery zeal and ardent love, with the joyous ecstasy of anticipated salvation and the nameless horror of ever-threatening damnation. All this wealth of deep and keen emotion