The student should familiarize himself with all technical terms used in this lesson, as they will be referred to frequently in the succeeding lessons on repairing and regulating.

QUESTIONS ON LESSON III.

Without reference to anything but the cut, give technical names for parts of action represented by the following letters or abbreviations: 

    1.  Bnc R, c, G P, BP, Ky, L.

    2.  Bm, Cpn, E, W, j, js, g, and M R.

    3.  Rr, B C, B R, B C W, Bl, and Bl W.

    4.  Bt, H, H S, H R, and sr.

    5.  S, D, D L, D R, s, B, and B B.

    6.  Explain the purpose and movements of the jack.

    7.  Describe a flange and the joint of same.

    8.  Give names of the four flanges shown in cut.

    9.  What is the purpose of the back catch and back check?

    10.  Explain the mechanical action of the damper pedal, and its
    effect when used; also, that of the soft pedal.

LESSON IV.

ACTION OF SQUARE AND GRAND PIANOS.

ACTION OF THE SQUARE PIANO.

Up to about the year 1870, the square was the popular piano.  The grand has always been too expensive for the great music-loving masses, and previous to this time the upright had not been developed sufficiently to assert itself as a satisfactory instrument.  The numerous objections to the square piano forced its manufacture to be discontinued a few years after the introduction of the improved new upright.  Square pianos that come, at the present day, under the hand of the tuner, are usually at least fifteen years old, and more frequently twenty or more.  However, in some localities the tuner will meet numbers of these pianos and he will find them a great source of revenue, as they are almost invariably in need of repair.

Compare the three cuts of actions in the study of this lesson.

The main constituent parts of the square action are similar in appearance to those of the upright; in fact, most of the parts are the same in name and office.  However, the parts are necessarily assembled very differently.  In the square action, the hammers strike in a vertical direction, while in the upright they strike in a horizontal direction; the motion of the key being the same in both.

Of the three types, the square is the simplest action, as many of the parts seen in the upright and grand are entirely absent in the square.

Beginning with the key, it has its balance pin, guide pin, cushions, etc., practically the same as in the other types.

The bottom, or key rocker, is reversed in the square; the end transmitting the motion being nearest the performer.

The extension and wippen are absent in the square, as the jack is attached directly to the bottom or key-rocker.