英語の和訳をお願いします。
Romanesque art was not abstract, but because it was representational only within limits, partly because the artists were incapable of representing nature was not art, stained glass was a magnificent midium for this formalizing genius, which made features of limitations; by emphasizing the black lines of the lead joints they increased the brilliance of their blues and rubies, and by bending their iron supports into medallions and outlines of borders they gave their glass a jewel-like quality that quite transformed the interior of their churches.
At the same time there was a transformation of Church music, the begining of polyphony.
The organum, the singing of the same melody in parellel fourths and fifths, inevitably developed into the conductus, the singing by two or more voices of different melodies that harmonized with the main one, or canto fermo. Moreover, unlike plainsong and organum, the conductus was metrical, for the words were those of met-rical Latin hymns. Much as the nave and chancel of a church had become a progression of bays defined by wallshafts and intersecting ribs, so music became a measured progression of notes that could have been defined by bar-lines. It was still all very elementaly, and in cathedrals, in Winchester Cathe-dral at least, the singing was led by a primitive organ, the greast keys of which had to be thumped with fists, while seventy blowers, for each pine had its own bellows, supplied wind for the two players.