270 



Mr. C. S. Myers. The Influence of 



composition, were covered on their inner surface with a thick layer of horsehair. 

 The floor, also isolated from the rest of the building, was similarly covered. 

 By this means the reflection of sounds from the walls and floor was reduced 

 to a minimum. The subject sat blindfold in the centre of the room. A 

 sound perimeter (P, cf. also fig. 2) was constructed for these experiments. 

 It consisted essentially in an arm M, silently rotatable about Z by means of 

 the handle L, and carrying a funnel-shaped mouth F, which was connected 

 by a flexible pipe with the sound-producing apparatus in a neighbouring 

 room. The centre about which the arm of the perimeter rotated was 

 always placed over the point midway between the two ear-holes. The 

 perimeter could be turned round the axis A so as to give sounds in the vertical 

 as well as in the horizontal plane. 



With the perimeter arranged as in fig. 2 the sound could be presented at 

 any point in the median vertical (sagittal) plane, i.e. directly in front 

 of (= 0°), above (= 90° v.) or behind (= 180°) the subject, or at any inter- 

 mediate point. The sound could also be presented, as in the arrangement of 

 the perimeter shown in fig. 1, at any point in the horizontal plane at the 

 level of the ears, i.e. directly in front of (= 0°) or behind (= 180°) the 

 subject, or exactly opposite the right or left ear (= 90° h. or 270° h.) or at 

 any intermediate point. 



The pipe connecting the funnel with the sound-producing apparatus was 

 enveloped with layers of cotton wool and bandages, and passed through 

 a tube in the wall of the sound-proof room to a very wide-mouthed horn H, 

 such as is used in connection with the phonograph when heard in large 

 halls. Before this horn were arranged four of Stern's tone-variators, Vi, V2, 

 V 3 , V4, blown by wind from a hydraulically worked organ bellows. These 

 tone-variators, one of which, Yi, was unenclosed, produce relatively pure 

 (overtone-free) tones ; they are essentially bottle whistles, each consisting of 

 a mouthpiece fixed over a metal air-containing cylinder. The pitch of the 

 note depends on the height and circumference of the cylinder, the base of 

 each cylinder being movable so as to adjust the pitch accurately. The first 

 or largest tone-variator was arranged to emit a (fundamental) tone of 

 215 vibrations per second. The second variator gave the first overtone, the 

 third gave the second, and the fourth gave the third overtone, of this 

 fundamental, i.e. they emitted tones of 430, 645, and 860 vibrations per 

 second respectively. In order to reduce and to vary at will the loudness of 

 these overtones, the three corresponding variators, V 2 , V 3 , Y it were each 

 enclosed in a wooden box, open at one end. The open end of each box 

 could be more or less completely closed by means of an adjustable slide, 

 thus allowing the intensity of the overtones (and hence the timbre of the 



