[45] The preface of the _Componimenti Musicali_ of 1706. Mattheson exaggeratingly says that "to compose well a single recitative in keeping with the feelings and the flow of the phrase as Keiser did, needs more art and ability than to compose ten airs after the common practice." [46] Compare the _recitative_ in the first great cantatas of J. S. Bach, "Aus der Tiefe, Gottes Zeit," which cover from 1709 to 1712-14, with such _recitatives_ from "Octavia" of Keiser (1705), notably Act II, _Hinweg, du Dornen schwangere Krone!_ Melodic inflections, modulations, harmonies, grouping of phrases, cadences, all in the style of J. S. Bach even more than in that of Handel. [47] See in _Croesus_ (1711) the air of Elmira, with flute, which calls to mind a similar air from _Echo and Narcissus_ by Gluck. [48] In this genre a scene from _Croesus_ is a little masterpiece in the pastoral style of the end of the eighteenth century; and is very close to Beethoven. [49] Such as the _Song of the Imprisoned Croesus_, which calls to mind certain airs in _The Messiah_. [50] I need only cite one example: it is the air of Octavia with two soft flutes, "Wallet nicht zu laut," one of the most poetic pages of Keiser, which Handel reproduced several times in his works, and even in his _Acis and Galatea_, 1720. [51] Postel, who used seven languages in the Prologues of his Libretti, was opposed to this mixture in poetical works, "for that which ornaments learning," he says, "disfigures poetry." [52] Certain German operas mix High German, Low German, French and Italian. [53] He was born at Hamburg in 1681, and died there in 1764. See L. Meinardus: _J. Mattheson und seine Verdienste um die deutsche Tonkunst_, 1870; and Heinrich Schmidt: _J. Mattheson, ein Förderer der deutschen Tonkunst_, 1897, Leipzig. [54] He violently attacked in the _Volkommene Kapellmeister_ (1739) the "Pythagoreans" of whom the chief was Lor. Christoph Mizler, of Leipzig, who attempted to work out music on the lines of mathematics and logic. With the "Aristoxenians" (harmonists) he wished to rescue music from an iron vice, from the hands of the skeleton of a dead science, and from scholasticism. The ear was his law. "Let your art be encompassed where the ear alone reigns: that should suffice. Where nature and experience leads you, all is well. Do it, play it, sing it; for wrong doing, avoid it, efface it" (_Das forschende Orchestre_). Against the scholastic, he opposed the fecund and living harmonic science (_Harmonische Wissenschaft_); he demanded that the latter should be taught in the universities, and offered to bequeath a large sum to found a Chair for a musical lectureship in the college of his native city.