PRINCIPLES OF MOVEMENT FIG. 10. 103 Movements should always seem to be initiated from the trunk and to flow outward to the extremities. When the arm is moved the motion must appear to start from the shoulder or upper arm, then to follow on in the elbow and lower arm, and finally to trail into the wrist and hand. When one waves a pennant the small tip follows the undulations of the larger and fixed part, and the hand should appear to obey the same law. Fig. 1 shows the correct position of the hand as the arm moves in an upward line. The body should appear to carry the head with it, so that in the performance of a bow or curtsy, for instance, the motion of the head will seem to follow and complete the movement of the trunk. If movements seem to begin with the hands or feet or head, the trunk will look as if it were being pulled along or run away with. The body will not look poised unless its movements center about the trunk. FIG. II. Other rules of movement prescribe that all parts of the body shall be kept as flexible as may be; or, rather, as responsive as possible to the slightest impulse to movement. Movements should usually be made in curves. In changing from one position to another the arms and legs should not be kept extended, but should be drawn in toward the body and then extended into the new position. In this way there is a constant reference to the center of balance. The arms should never hang straight down at the sides, but when they are at rest should hang in a slight outward curve. These rules are a part of the formal technique of dancing. They indicate some of the conditions to which artistic imagination is limited when it works with the moving human form as its medium. READING REFERENCES CZERWINSKI: "Geschichte d. Tanzkunst." VUILLIER: "History of Dancing." GROVE: "Dancing." EMAMNUEL: "La Danse Grecque." GIRAUDET: "Traité de la Danse." GROSSE: "The Beginnings of Art." Chap. VIII. CHAPTER VII MUSIC Primitive Music. The two sources of musical effect are rhythm, which unites music with other arts, and tone relationship, which separates it from others. In primitive music, we are told by those who study savage customs, the rhythmic element is far more important than the tone sensations. The practice of keeping time for dancers by shouting and beating drums is the original of music. "Dance, poetry and music", says Grosse,1". . . form a natural unity, which can only artificially be separated." Time and rhythm are managed by savage performers, it is said, with truly wonderful precision. In pitch relationships, however, they seem to be less precise. It is this latter fact, probably, which has led to the belief that primitive folk employ intervals which are foreign to our scale and cannot be represented by our notation. Fillmore, who made a study of many of the American Indian songs, thinks this is a mistake. He says: "Not one has an interval different from those we employ." He says that the Indians often sing these intervals a little off key, just as civilized persons may, but when they hear the correct and the incorrect intonations reproduced they choose the correct ones, insisting that that was what they meant to sing. Primitive songs are simple and 1 Op. cit. 2 2 "Harmonic Structure of Indian Music." Am. Anthro., vol. 1. 1 monotonous, sometimes having as component tones only a key-note with its third and fifth. The principle of tonality is commonly observed. Wallaschek maintains that savages have also a perception of harmonic relations. He says: "The Bechuana also sing in harmony. The melody of their songs is simple enough, consisting chiefly of descending and ascending thirds, while the singers have sufficient appreciation of harmony to sing in two parts." It is safe to assume that the musical perception and practice of civilized peoples are but the elaboration and refinement of the perceptions and practices of primitive peoples, or, as Meyer says, "that the fundamental psychological laws of music are the same all over the world." 2 Physical Basis of Tone Differences. The physical basis of sound is the vibration of some body, such as a taut string, a column of air, a piece of metal, wood or glass. These vibrations are communicated to the air, and the air waves in turn set up motion in the mechanism of the ear. When the air waves are irregular or aperiodic in their vibration the sound we hear is called a noise; but when the air waves are periodic the sound is called a tone. It takes at least two vibrations to give us the impression of tone; hence a sound only one vibration long is also a noise. Noises are commonly more complex than tones, being, indeed, combinations of tones. whose vibrations interfere with one another. Noise and tone do not strictly exclude each other; there is often regularity enough in a noise to give it definite pitch, and there are often perceptible elements of noise in agree 16 Primitive Music." 244 The Psychology of Music." Am. Jour., vol. xiv. PHYSICAL BASIS OF TONE 107 able tone combinations. The recognized medium of musical expression is tone. Every tone has, besides its duration, three attributes — intensity, pitch and quality. The intensity of a tone depends upon the amplitude of the air waves which strike the ear. We can easily see the greater amplitude of a vibrating string when it is plucked more forcibly than usual. The pitch of a tone depends upon the number of air vibrations per second which reach the ear; the greater the number, the higher the tone. The limits of hearing, that is, the lowest and the highest tones which the human ear can well detect, are about 16 and 50,000 vibrations respectively. Most of our musical experiences fall considerably within these limits, ranging between about 64 and 5,000 vibrations. The human ear is able to discriminate much finer differences of tone than those in practical use in any musical scale. A difference of onefourth of a vibration can easily be told under favorable circumstances; whereas, in our scale, the smallest intervals differ (in the octave of middle C, 256 vibrations) by fifteen to thirty vibrations, approximately. The quality, timbre, or, better, the clang-tint of a tone is that property which distinguishes tones of the same pitch and intensity from one another. The peculiarity which allows us to speak of organ-tone, piano-tone, cornet-tone etc., is the characteristic element of clangtint. Clang-tint depends upon the presence of overtones which accompany a fundamental tone. In terms of vibrations this means that there is a difference in the complexity of the air waves which strike the ear. A sonorous body — a string, for example vibrates as a |