§ 104.11. =Church Music= (§ 88, 2).--The Gregorian _Cantus firmus_ soon fell into disfavour and disuetude. The rarity, costliness, and corruption of the antiphonaries, the difficulty of their notation and of their musical system, and the want of accurately trained singers, combined to bring this about. Singers too had often made arbitrary alterations. Hence alongside of the _Cantus firmus_ there gradually grew up a _Discantus_ or _Cantus figuratus_, and instead of singing in unison, singing in harmony was introduced. Rules of harmony, concord, and intervals were now elaborated by the monk Hucbald of Rheims about A.D. 900, while the German monk Reginus about A.D. 920 and the abbot Opo of Clugny did much for the theory and practice of music. In place of the intricate Gregorian notation the Tuscan Benedictine Guido of Arezzo, A.D. 1000-1050, introduced the notation that is still used, which made it possible to write the harmony along with the melody, counterpoint, _i.e._ _punctum contra punctum_. The discoverer of the measure of the notes was Franco of Cologne about A.D. 1200. The organ was commonly used in churches. The Germans were the greatest masters in its construction and in the playing of it.--Continuation, § 115, 8. § 104.12. =Ecclesiastical Architecture.=--Church building, which the barbarism of the 10th century, and the widespread expectation of the coming end of the world had restrained, flourished during the 11th century in an extraordinary manner. The endeavour to infuse the German spirit into the ancient style of architecture gave rise to the =Romance Style of Architecture=, which prevailed during the 12th century. It was based upon the structure of the old basilicas, the most important innovation being the introduction of the vaulted in place of the flat wooden roof, which made the interior lighter and heightened the perspective effect. The symbolical and fanciful ornamentation was also richly developed by figures from the plants and animals of Germany, from native legends. Towers were also added as fingers pointing upward, sometimes over the entrance to the middle aisle or at both sides of the entrance, sometimes over the point where the nave and transepts intersected one another, or on both sides of the choir. The finest specimens of this style were the cathedrals of Spires, Mainz, and Worms. But alongside of this appeared the beginnings of the so-called =Gothic Architecture=, which reached its height in the 13th and 14th centuries. Here the German ideas shook themselves free from the bondage of the old basilica style. Retaining the early ground plan, its pointed arch admitted of development in breadth and height to any extent. The pointed arch was first learnt from the Saracens, but its application to the Gothic architecture was quite original, because it was not as with the Saracens decorative, but constructive. The blank walls