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First. When several keys are to be played one after another, either in ascending or in descending, and that five fingers are not sufficient for this purpose, the four longer fingers must never be turned over one another; but we must either pass the thumb under, or pass the three middle fingers over the thumb.
Secondly. The thumb must never be placed on the black keys.
Thirdly. We must not strike two or more keys one after another with the self-same finger; for each key must always retain its own finger.
Fourthly. In runs, the little finger should never be placed on the black keys.
Fifthly. In chords and wide extensions, however, the thumb, as well as the little finger, may occasionally fall upon the black keys.
Sixthly. The fingering given for the scales must be resorted to everywhere, and as much as possible.
Seventhly. At each note that we strike, we must consider whether, for the following notes, the appropriate fingers stand in readiness.
In general, that mode of fingering must be chosen by which we may most easily and naturally be able to maintain a tranquil and fine position of the hands, a firm and perpendicular percussion, as well as a correct holding down
