For many years Beethoven worked with a professional copyist whose work he greatly admired: Wenzel Schlemmer. When Schlemmer died in 1823, Beethoven looked for other copyists, with whom he was not, however, always very satisfied. In April 1824 Peter Gläser, a copyist at the Josephstadt Theatre, made a copy of the Missa solemnis and the Ninth Symphony for Beethoven. The composer was indignant about Gläser's work and writes asking him to take more care with the copying. He writes to Gläser that he should ensure that the texts (for the Ninth Symphony op. 125) should be written underneath the music as in the model and explains his principle of writing text under music.
He asks him to add the coda. Beethoven stresses that it had merely been forgotten in the first copy and quotes Haydn, Mozart and Cherubini, who had also not shied from making changes to their own works.
