THE METRONOME IN BEETHOVEN'S TIME
Attempts to measure pace by mechanical means prior to the 18th century proved inadequate and were quickly forgotten. Quantz's method of measuring pace by the human pulse was by far the best one and it remained successful until it was superseded by the invention of the metronome. This instrument (first called a "chronometer") was introduced by Johann Mälzel in 1815 (a model is now in the Museum der Gesellschaft der Musikfreunde in Vienna). After 1820 Mälzel constructed a second, different model, which became the pattern for the modern metronome.
The use of this revolutionary instrument for measuring pace seems at first to have caused so many errors that Mälzel felt obliged to publish a pamphlet, in which he censured the incorrect application of his innovation followed by instructions on how to use it; to these he added a drawing of the first model with its range expressed by figures (Table No. 2). Two tables follow, the first one showing time signatures and note-values with their corresponding metronome figures for slow, moderate and fast pace (Tableau No. 1), and the other containing tempo directions and metronome figures as employed by various composers (Tableau No. 3). A pertinent section of the pamphlet (in the Library of the Gesellschaft der Musikfreunde in Vienna) reads:
"Information on the Metronome by J. Mälzel May 1818
". . . In order to dispel the slightest doubt as to the inadequacy of the Italian terms used for denoting pace, a series of indications showing the two methods, which are set alongside one another, has been collected in Table 3. This shows not only that different composers have attributed varying meanings to identical terms, but also that a given composer has not always applied the same meanings to certain given words. This table also gives examples of pieces by different composers which bear the same metronome marks but with the pace indicated in the old manner by different terms. To give an example: MM. Cherubini and Clementi have given the indication Allegro to some compositions, one of which bears the metronome mark= 50 and the other = 126, which gives to the second piece more than twice the pace of the first one; M. Cramer gave to two pieces marked Moderato two very different metronome