Hans van Nieuwkoop

Slurs and tempo indications in Mendelssohn's organ music
Het ORGEL 93 (1997), nr. 9, 21-28 [summary]

Mendelssohn was a precise musician, as historical evidence proves, and showed great interest in correct editions of his music. So we should take his slurs and tempo indications seriously. Every slur in Mendelssohn's organ music has three aspects: the first note has an expressive character (1), then follows a crescendo-diminuendo process (2), and the last note has to be diminuendo (3). Mendelssohn's slurs indicate furthermore where one should play legato or non-legato; how hemiolas and upbeats should be interpreted; where expression is needed (slight acceleration followed by a retard).

Mendelssohn was the first composer to use metronome indications in organ music. These indications show that between at least two movements of each Sonata a relationship exists. The relationship between slurs and metronome-indications is equally important: the tempo [eighth note] = 100 MM in the last movement of Sonata 6 seems to be too fast, but appears to be excellent when one respects the slurs.