Now there are three chief reasons why the musician would do well to study transposition: 

1.  For the purpose of song accompaniment.

2.  As an aid to committing music to memory, especially that written in a form where different keys are used for the presentment of the same material.

3.  As an infallible test of a sound ‘general’ musical education.

The last reason is not often advocated, but a little thought will show that it is impossible for the average student, not specially gifted in any way, to transpose even an easy piece of music at sight on the piano, without proving the possession of a trained ear and a knowledge of practical harmony.  For class work with children it can be made a still more valuable test of progress.  For the average child will be quite unable to transpose a simple ear test—­such as d f m l s t, d—­on the piano, from one key to another, say a fifth away, without a good deal of accurate knowledge.

The first exercises in transposition will be very simple—­any child of seven or eight years old, who can sing at sight, and take down ear tests, in the keys of C and G major, can be expected to do them.  They consist in: 

1.  Singing any well-known hymn-tune, or simple melody of the Folk Song type, using the Sol-fa names of the notes.  It should be sung phrase by phrase, until every child in the class is sure of the correct notes.

2.  The children should now go in turn to the piano, and each play a phrase of the melody, first in C major, then in G.

It is important to emphasize the fact that the tune must be well known to them, or an extra difficulty will be introduced.

As the children learn more and more keys, these tunes should be transposed into them.

Provided the class does not consist of picked musical children, there will always be a few in it who do not learn the piano.  This work will be one of their opportunities for learning a little about it.  Interesting results have been obtained from such children, if the teacher is enthusiastic and ready to help.

By the time that the class has begun the study of three-part chords the transposition will become more and more interesting, as sequences of chords can now be transposed.  When the first steps in extemporizing on the piano are begun, the transposition advances by leaps and bounds.  The children will be delighted to play their little tonic and dominant accompaniments in every key—­to change from major to tonic minor by flattening the third and sometimes the sixth of the scale.

There is a sense of freedom and power in such work, to which the class will readily respond.  They soon realize that certain melodies ’only sound nice’ in such and such a key, and in this way the foundation of a ‘colour sense’ will be laid.  Also, apart from the question of the key in which a melody sounds best to a child, another point comes into notice.  The child cannot sing certain notes in certain melodies unless it keeps within a certain range of keys.  This teaches them something.  The point has been referred to in the preceding chapter.