an apparatus with which one can indicate the exact tempo of a piece by the ticking sounds or flashes of light which the metronome produces. Although many forms of metronomes have been used since its invention by Loulie in 1696, today the "ticking" metronome which was invented by Johann Nepomuk Maelzel
(1772-1838) in 1816 is used. The name Maelzel Metronome is
usually abbreviated in scores as M.M., or just M.
The metronome is constructed with an oscillating rod, with an immovable weight at the bottom and a movable weight on top. By adjusting the movable weight on the rod, it is possible to slow or quicken the pace of the ticking as desired, according to the scale of tempi printed on the rod. M.M. = 60 indicates that the metronome ticks 60 times per minute, and that the tempo is 60 quarter-notes per second.
Beethoven seems to have been the first composer to use metronomic indications in his scores.
Following is the table showing the different tempi as they are printed on the metronome.
Largo: 45 beats per minute
Adagio: 54 beats per minute
Andante: 66 beats per minute
Moderato: 80 beats per minute
Allegretto: 100 beats per minute
Presto: 144 beats per minute
Prestissimo: 184 beats per minute.
Of course, 80 half-notes per minute will be much faster than 100 quarter notes per minute, since 80 half-notes equal 160 quarter-notes.
Is the metronome a musical instrument? Well, in 1692 the Hungarian born composer, Gyorgy Ligeti, wrote a "Symphonic Poem For 100 Metronomes".
