strike the props for which the openings are left in the back
extremities of action.

While the action is out, study carefully the purpose of every part and
its movements, referring to this and the previous lesson until you
have thoroughly mastered the entire mechanism. Do not rest until you
can name correctly everything you see and know its use so well that
you could explain it satisfactorily to an inquirer. Sometimes the
tuner is asked a great many perplexing questions and is expected to
respond intelligently.

We have dealt with the three types of actions that are most commonly
found in the three types of pianos. The student must bear in mind that
there are numerous manufacturers of actions, and that each has his
peculiar method of constructing his special action to bring about the
desired results, which are practically the same in all cases; and
consequently, while a variety of construction will confront the
beginner in piano regulating and repairing, he will understand the
construction and requirements of any action that may demand his skill
from the foregoing instruction, if properly mastered. In this, as in
all other mechanical professions, one's inventive genius must often be
summoned to assist in surmounting obstacles which are sure to arise
unexpectedly.


QUESTIONS ON LESSON IV.

1. From a philosophical point of view, which do you consider the
easiest and most perfect of the three types of actions? Also give
reasons.