Schedule of Classification 



PAGE 



A caustic Figures ... 517 



Curved Plated 518 



Bells 518-519 



9130 Vibrations of Gases in Tubes 

 and other Cavities. 

 Effects of Apertures 519-522 

 Kundt's Dust-Figures ... 520 

 Pipes. (See also 9410.) 520-521 

 Organ-pipes ... 520-521 



Singing Flames ... 521-522 



Chemical Harmonicon 521-522 

 Sounds from Heated Tubes 522 



9135 Forced Vibrations 522 



9140 Resonance. Resonators. Ob- 

 jective Combination- 

 Tones. (See also Phy- 

 siology 3545.) ... 522-524 



Resonance 522-523 



Resonators 523 



Combination-Tones 523-524 



Propagation of Sound. 



9200 General 524-527 



Kinetic Theory 525 



Propagation of Sound in 



Particular Media ... 526. 



9210 Velocity of Sound ... 527-530 



Doppler's Principle 527-528 



Experiments ... ... 528 



Theory 529 



Velocity of Sound in Air 



in Tubes ... 529-530 



Velocity of Sound in 



Various Media ... 530 



9220 Reflection and Refraction of 



Sound. (See also 9040.) 530-531 

 Reflection ... 530-531 



Refraction 531 



9230 Interference and Diffraction 



of Sound. Beats 531-533 



Interference ... 53 1 -532 



Beats 532-533 



Diffraction 533 



9240 Damping of Sound-Waves 

 by Viscosity and Heat- 

 Conduction 533 



9250 Acoustic Transparency 533-534 

 Fog Signals ... 533-534 



9255 Acoustics of Buildings ... 534 



Methods of Analysis and Measure- 

 ment. 



9300 General 534 



9310 Methods of Illustrating and 



Observing Air- Waves 534-535 



Sensitive Flames 535 



9320 Measurement of the Velocity, 

 Amplitude, Energy, and 

 Frequency of Souud- 



Waves 535-537 



Amplitude 535 



9340 



PAGE 



Energy 535 



Intensity 535-536 



Measurement ... ... 536 



Frequency 536-537 



Measurement ... ... 536 



Siren 537 



Measurement of Velocity 537 



Analysis of Compound Sound 



Waves ... 537-538 



The Physical Basis of Music and the 

 Sensation of Sound. 



9400 General 538 



Music 538 



9410 Musical Instruments 538-540 



Mechanism for playing 

 Musical Instruments and 

 for recording Motion of 



Keys 539 



Pipes. (See also 9130.} ... 539 

 9420 The Voice. Speaking 



Machines ... 540-542 



Speaking Machines 540-541 



Phonograph ... 540-541 



The Voice 541-542 



Vowels 541-542 



9430 Limits of Audition as De- 

 pendent on Intensity and 

 Pitch. (See also 9500; 

 Physiology 3533.) 542-543 



9440 Modification of Vibrations in 



Transit through the Ear 543 



9450 Quality of Musical Tones. 

 Consonance and Disso- 

 nance. Chords. Phy- 

 sical Explanation of 

 Harmony. (See also 

 Physiology 3540-3555.) 543-545 

 Musical Intervals ... ... 544 



Quality of Musical Tones 544-545 

 9460 Absolute Pitch. Standards 



of Pitch 545-546 



Absolute Pitch 545 



Standards of Pitch 545-546 



Tuning-Forks. (See also 



9110.) 545-546 



9470 Scales. Temperament 546-548 



Scales 546-547 



Numerical Evaluation 546-547 

 Temperament ... 547-548 



Physiological Acoustics. (See also 

 Physiology 2753, 4141, 3500-3590.) 



9500 General. (See also 9430.) 548-549 

 9510 Arrangement and Action of 

 the Vocal Organs. (See 



9420.) 549 



9520 Arrangement and Action of 



the Ear 549-550 



Audition 549 



