In the year 600 St. Gregory improved upon these chants, inventing the scale of eight notes. His system is the basis of our modern music. From the close of the eleventh to the commencement of the fourteenth century, minstrels, _jongleurs_, or troubadours, were the principal devotees of music. They seem to have been its custodians, so to speak; and to their guild many of the knights belonged. Some of the kings and nobles of the time were also, in a sense, troubadours; such as, for instance, Thibault of Navarre, and William the Ninth of Poitou. These roving musicians, who generally united the qualities of the poet, the musical composer, and performer, were treated with much favor by princes and all the nobility, and were everywhere warmly welcomed for a long period. It is, however, far from pleasant to have to say that this for a long time noble class of musicians, to whom we owe so much for the preservation unbroken for three hundred years of the chain of musical life, as well indeed, also, as that of general literature, spoiled perhaps by the excessive praises and indulgences accorded them, became at last quite dissolute, and fell from their high position. All royal favors were finally withdrawn from them, and orders for their restriction were issued from the throne. Mr. B.W. Ball (in that faithful exponent of art, "The Boston Commonwealth") thus expressively sings the story of the ancient troubadour, styling him-- "THE POET OF OLD." Once the poet wandered, With his lyre in hand,-- Wandered, singing, harping, On from land to land. Like a bird he hovered; And, where'er he came, Kindled he each bosom With his song to flame. Careless of the morrow, Journeyed he along; Opened every portal To the sound of song. _Sua sponte_ heart's-ease In his bosom grew: Happiness as birthright, Like the gods, he knew. All life's haps and changes On his chords he rung: Every thought, emotion, In him found a tongue. Voiced he for the lover Passion of his breast; Feigned he, death to lighten, Islands of the Blest. Up in ether throned he Gods, the world to sway,-- Gods to bend and listen While their votaries pray. Soul and sense, enchanted, Drank his accents in: E'en to marble bosoms He his way could win. From her casement Beauty Leaned his song to hear: E'en the haughty conqueror Bent a willing ear; For without the poet And his epic lay Passed his vast existence, Whirlwind-like, away,-- Trace nor vestige leaving Where his legions trod, Which the year effaced not From the vernal sod. Thus the poet wandered In a nobler time,-- Wandered, singing, harping, Free of every clime.