29. Contrast Kollmann’s understanding of the structural place of cadenza with a passage from Carl Czerny’s Systematic Introduction to Improvisation on the Pianoforte, op. 200, ed. and trans. Alice L. Mitchell (New York and London: Longman, 1983), 34–35: “The older concertos (for example, all of Mozart’s, most of Beethoven’s, etc.) have a prolonged pause towards the close of the last Tutti, after which the performer has to improvise a grand cadenza. These … can be extended considerably and the performer can indulge in all conceivable modulations therein. But all interesting subjects from the concerto as well as its most brilliant passages must make their appearance here [my emphasis]. These cadenzas can be regarded to some extent as independent fantasies, and … the performer can display his artistry here a good deal more than in the concerto itself.” In evidence, Czerny gives a cadenza for the first movement of Beethoven’s Opus 15. Its 105 measures (counting the actual quantity of the unmeasured measures) violate the spirit and letter of Kollman’s rules. In this it is not unlike the third of Beethoven’s cadenzas for the movement, which is yet longer and even bolder in its modulations. While Czerny’s Opus 200 seems to have been written in the late 1820s (Mitchell, xii), it may well convey a view of cadenza that was developed during his studies with Beethoven between roughly 1800 and 1803 (Czerny’s dates). Czerny actually performed Opus 15 in Vienna in 1806.