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Show DBNSMOBB] NORTHERN UTE MUSIC 207 The first purpose of the study was to determine the relation of the drumbeats to the accents of the voice. In the photograph there are 62 drumbeats, which are indicated on the photograph by white *' s, and they are numbered consecutively by numerals in circles as ® . The effect of the drumbeat is to produce a short series of vibrations of the general pattern shown in figure 20. When the voice is very soft or silent, the drum record is as shown at @ and ® ; when it is superposed on the voice, the effect is shown by a few extra wide vibrations, as at © , ® , and ® . By careful study it has been possible to identify all of the drumbeats, though some of them are faint. The dots in a row below the sound record are time signals one one-hundredth second apart. In taking this photograph the film was moved by hand, resulting in a varying speed; when the dots are nearer together, the corresponding speed is slower. The numerals between the *' s are the time intervals between the drumbeats in hundredths of a second. The first study of the photograph shows a remarkable regularity in the rhythmic beats of the drum. The beats occur in pairs following an accented tone of the voice; 30 pairs are shown on the photo- Ratio of 2: 3 • • • • • • • • » Ratio of 1: 2 • » # # ^ ^ # # FIG. 21.- Ratios of drumbeats graph. The interval between the two beats of a pair is, in 17 instances, 0.29 second; there are six intervals of 0.28 second, four of 0.30 second, two of 0.27 second, and one of 0.31 second. The interval may then be said to be 0.29 second, with a variation rarely exceeding 0.01 second either way. The average of intervals between the pairs of beats is 0.45 second, there being seven of this length; there are 10 intervals of 0.44 second, five of 0.46 second, three of 0.43 second, and five of 0.47 second. Thus the average interval between pairs is 0.45 second, the variation from this value rarely being more than 0.01 second and never being more than 0.02 second. The ratio of the interval between the two beats of a pair to the interval between pairs is almost exactly 2: 3, and this ratio is maintained with mechanical regularity throughout the song. It was suggested that the drumbeats might be thought of as occurring in triplicate with one beat of each triplet omitted. This would require a ratio of 1: 2. The difference between the two ratios is shown in the spacing of the dots in the following rows ( fig. 21): A further noticeable peculiarity is that the first beat of a pair of drumbeats follows the beginning of an accented voice tone with great regularity. Of 25 such instances identified on the photograph |