5. Key shown by key signature placed at the beginning of each staff.
6. Rate of speed, dynamic changes, etc., shown by certain Italian words (allegro, andante, etc.), whose meaning is as universally understood as staff notation itself.
APPENDIX B
Musical Instruments
1. Broadly speaking, musical instruments may be divided into two classes, viz.: (1) those that have a keyboard and are therefore capable of sounding several tones simultaneously; (2) those that (as a rule) sound only one tone at a time, as the violin and trumpet. The piano is of course the most familiar example of the first class, and a brief description is therefore given.
The piano was invented about two hundred years ago by Cristofori (1651-1731), an Italian. It was an enormous improvement over the types of keyboard instrument that were in use at that time (clavichord, harpsichord, spinet, virginal) and has resulted in an entirely different style of composition. See note on embellishments, [p. 26].
2. The most characteristic things about the piano as contrasted with its immediate predecessors are: (1) that on it the loudness and softness of the tone can be regulated by the force with which the keys are struck (hence the name pianoforte meaning literally the soft-loud); (2) the fact that the piano is capable of sustaining tone to a much greater extent than its predecessors. In other words the tone continues sounding for some little time after the key is struck, while on the earlier instruments it stopped almost instantly after being sounded.
The essentials of the piano mechanism are: