206 FROM FISH TO PHILOSOPHER 



the 'Perpetuum mobile,' Op. 119.) She played 5995 

 notes in four minutes and three seconds, or more than 

 twenty-four notes per second. Recognizing that each 

 note required at least two volimtary movements— flexion 

 and extension— as well as lateral movements in either di- 

 rection, Sir James estimated that no less than 72 distinct 

 motor actions were required per second, each accurately 

 timed and exercised with judgment. (This calculation 

 takes no account of the movements of the hand, fore- 

 arm, arm, and foot.) 



The Mendelssohn presto does not, however, present 

 the most complex kinds of diflBculties that are to be en- 

 countered in piano music, difficulties that separately and 

 collectively serve to retard the over-all speed set by the 

 limitations of either the keyboard or the fingers. As 

 demonstrated to the writer by Dr. David Saperton, a 

 five-note *blind trill,' or tremolo, with each hand play- 

 ing alternate notes, can be played at a rate close to 80 

 notes per second. This is not necessarily the greatest 

 speed, though it is one compatible with good musical 

 rendition. At this level, speed may be limited by the ac- 

 tion of the piano, since the resistance offered by the key, 

 the depth to which the key must be depressed, the 

 length of the lever from tip to fulcrum and fulcrum to 

 hammer, the speed of rebound of key and hammer, and 

 other mechanical features, all contribute to the Hmita- 

 tions imposed by the keyboard itself. A greater speed 

 can possibly be achieved with certain types of electronic 

 organs where mere contact between the finger and the 

 key may suffice to produce a tone, and it is conceivable 

 that, per finger, rapid chromatic passages on the violin 

 may exceed in speed the fastest possible action on the 

 piano. 



A rapidly executed trill is, however, only one of the 

 innumerable movements that a musician must execute, 

 which include the wide spacing of keys to be struck in 

 succession by a single finger, and hence wide lateral dis- 

 placements of both the finger and the hand or arm, as 



