Part 5 (1/2)

[Ill.u.s.tration: Fig. 51.]

[Ill.u.s.tration: Fig. 52.]

75. The _acciaccatura_ (or short appoggiatura) is written like the appoggiatura except that it has a light stroke across its stem.

[Ill.u.s.tration] It has no definite duration-value, but is sounded as quickly as possible, taking its time from that of the princ.i.p.al tone.

The appoggiatura is always accented, but the acciaccatura never is, the stress always falling on the melody tone. (See Grove, op. cit. Vol. I, p. 96.)

The use of embellishments is on the wane, and the student of to-day needs the above information only to aid him in the interpretation of music written in previous centuries. In the early days of instrumental music it was necessary to introduce graces of all sorts because the instruments in use were not capable of sustaining tone for any length of time; but with the advent of the modern piano with its comparatively great sustaining power, and also with the advent in vocal music of a new style of singing (German Lieder singing as contrasted with Italian coloratura singing), ornamental tones were used less and less, and when found now are usually written out in full in the score instead of being indicated by signs.

CHAPTER VII

SCALES

76. A _scale_ (from _scala_, a Latin word meaning _ladder_; Ger.

_Ton-leiter_) is an ascending or descending series of tones, progressing according to some definite system, and all bearing (in the case of tonality scales at least) a very intimate relation to the first tone--the _key-tone_ or _tonic_. (See p. 28, Sec. 78; also note 1 at bottom of p. 38.)

Many different kinds of scales have existed in various musical eras, the point of resemblance among them all being the fact that they have all more or less recognized the _octave_ as the natural limit of the series. The difference among the various scales has been in the selection of intervals between the scale-tones, and, consequently, in the number of tones within the octave. Thus _e.g._, in our major scale the intervals between the tones are all whole-steps except two (which are half-steps), and the result is a scale of _eight_ tones (including in this number both the key-tone and its octave): but in the so-called _pentatonic_ scale of the Chinese and other older civilizations we find larger intervals (_e.g._, the step-and-a-half), and consequently a smaller number of tones within the octave. Thus in the scale upon which many of the older Scotch folk songs are based the intervals are arranged as follows:

1 whole 2 whole 3 step-and- 4 whole 5 step-and- 6 step step a-half step a-half

The result is a scale of six tones, corresponding approximately with C--D--E--G--A--C in our modern system.

The term _pentatonic_ is thus seen to be a misnomer since the sixth tone is necessary for the completion of the series, just as the eighth tone is essential in our diatonic scales.

The following Chinese tune (called ”Jasmine”) is based on the pentatonic scale.

[Ill.u.s.tration]

77. In studying the theory of the scale the student should bear in mind the fact that a scale is not an arbitrary series of tones which some one has invented, and which others are required to make use of. It is rather the result of accustoming the ear to certain melodic combinations (which were originally hit upon by accident), and finally a.n.a.lyzing and systematizing these combinations into a certain definite order or arrangement. The application of this idea may be verified when it is recalled that most primitive peoples have invented melodies of some sort, but that only in modern times, and particularly since the development of instrumental music, have these melodies been a.n.a.lyzed, and the scale upon which they have been based, discovered, the inventors of the melodies being themselves wholly ignorant of the existence of such scales.

78. A _key_ is a number of tones grouping themselves naturally (both melodically and harmonically) about a central tone--the key tone. The word _tonality_ is often used synonymously with _key_ in this sense.

The difference between _key_ and _scale_ is therefore this, that while both _key_ and _scale_ employ the same tone material, by _key_ we mean the material in general, without any particular order or arrangement in mind, while by _scale_ we mean the same tones, but now arranged into a regular ascending or descending series. It should be noted in this connection also that not all scales present an equally good opportunity of having their tones used as a basis for tonality or key-feeling: neither the chromatic nor the whole-step scale possess the necessary characteristics for being used as tonality scales in the same sense that our major and minor scales are so used.

79. There are _three general cla.s.ses of scales_ extant at the present time, viz.: (1) Diatonic; (2) Chromatic; (3) Whole-tone.[13]

[Footnote 13: If strictly logical terminology is to be insisted upon the whole-tone scale should be called the ”whole-step” scale.]

80. The word _diatonic_ means ”through the tones” (_i.e._, through the tones of the key), and is applied to both major and minor scales of our modern tonality system. In general a diatonic scale may be defined as one which proceeds by half-steps and whole-steps. There is, however, one exception to this principle, viz., in the progression six to seven in the harmonic minor scale, which is of course a step-and-a-half. (See p.

33, Sec. 86.)

81. A _major diatonic scale_ is one in which the intervals between the tones are arranged as follows:

1 whole 2 whole 3 half 4 whole 5 whole 6 whole 7 half 8 step step step step step step step