[55] Especially in _Das neueröffnete Orchestre_ (1713), _Das beschützte Orchestre_ (1717), _Das forschende Orchestre_ (1721). We might say that the most fruitful of his theoretical writings is _Der Vollkommene Kapellmeister_ (1739), which might even to-day serve as the basis of a work on musical æsthetics, and that it was the work which produced a good part of our musicology. [56] He warns German musicians against going to Italy, whence they return like so many birds plucked of their feathers, with their great weaknesses hidden, and an intolerable presumption. He reproached Germany with not helping her national musicians, who were languishing and becoming extinct (_Volk. Kapellm._ and _Critica Musica_). [57] Twenty-four monthly books which appeared with interruptions from May, 1722, to 1725, Hamburg. There were musical polemics, correspondence, interviews with musicians, analyses of their books and works, a shoal of letters on the last opera, on the last concert, on the life of a musician, on a new clavier, on a singer, etc. One finds pre-eminently very solid musical critiques, perhaps the oldest which exist. The minute analysis of Handel's _Passion according to St. John_ was still celebrated when the work itself was forgotten. "It is perhaps," said Marpurg in 1760, "the first good critique which was written on choral music" since it sprang into being. [58] _Critica Musica._ [59] "When I think as a tone-poet (Tondichter)," he says, "I think of something higher than a great figure.... Formerly musicians were poets and prophets." In another place he writes, "It is the property of music to be above all sciences a school of virtue, _eine Zuchtlehre_" (_Vollk. Kapellm._). [60] _Grundlagen einer Ehrenpforte, worin der tüchtigsten Kapellmeister, Komponisten, Musikgelehrten, Tonkünstler, etc. Leben, Werke, Verdienste, etc., erscheinen sollen, 1740._ [61] _Vollkommene Kapellmeister_, 1739--he devoted a very important study, which he called the _Hypokritik_ (Pantomime), to it in this work. [62] _Ibid._ [63] In theory rather than in practice: for his operas are mediocre. Besides, he soon lost his taste for the theatre, his religious scruples being too strong for him. He wished at first to purify the Opera, to make the theatre something serious and sacred, which should act on the masses in an instructive and elevating manner (_Musikalischer Patriot_, 1728). Then he saw that his conception of a moral and edifying opera had no chance of being realised. Finally he lost his interest, and even rejoiced in 1750 over the final ruin which overtook the Hamburg Opera. [64] Mattheson, who spoke perfect English, and who became a little later the secretary to the English Legation, then resident in the interim, presented Handel to the English Ambassador, John Wich, who entrusted them both with the instruction of his son. [65] _Ehrenpforte._--Telemann, a co-disciple of Handel, says also that both Handel and he worked continually at melody.