=The Polyphonic and Monophonic Styles=.—Students frequently express surprise that the complicated polyphonic or contrapuntal system, which began to take shape in the 11th century, should appear first, historically. The pupil in composition begins his studies with the harmonic or monophonic style and is afterwards inducted into the polyphonic style. Why did the musical art develop along polyphonic and not on the simpler lines? It is intended that this lesson and those that follow shall show some of the influences that caused the line of development to move in a polyphonic and not in a monophonic direction. One thought is important to note. The elements of the simple, monophonic style _were present_ in the music of the early centuries, in the _people’s song_, principally; since, however, it was the Church that determined the direction of artistic composition, the simple, natural principles of melody-making _yielded precedence to_ a more highly organized, _intellectual process_. Before taking up the consideration of these matters it is well to get an understanding of the terms Monophony and Polyphony. There are two methods of giving harmonic support to a melody: by adding an accompaniment of chords, in simple or elaborated form, or by dividing the notes of the chords among three or more voices, which notes are sung or played simultaneously with the melody (an example is furnished by any simple air with accompaniment or a hymn-tune in four parts, in which the “air” or melody is in the soprano); this is Monophony, (_monos_—Greek for “one,” _phone_—“sound”); a second method is to add to the given melody other melodies, each independent in its movement up and down and in the duration of its successive sounds so far as concerns the movement and duration of the sounds in the given melody. This is Polyphony (_polus_, Greek for “many”). =Relation of Polyphonic to Modern Music=.—The exact relation of the Polyphonic Era to modern music has rarely been correctly estimated. Writers on this phase of the development of music are apt to lose themselves in wonder on noting the scientific growth of the art, and to express their great surprise that so peculiar an evolution should occur. This view of the question is totally inadequate. In order truly to estimate the value and influence of the period, it is necessary to inquire into the properties of the materials of musical construction which were developed, and the value of those materials as a foundation for the modern structure of music, apparently so different from the early forms, but yet so intimately related to these forms.