112 PART II. SOME IMPORTANT METHODOLOGICAL TERMS. 



stances. 9. Sounds possess no extremely definite qualities, such 

 as vision proffers us in red and green, apparently because the 

 constitution of objects varies indefinitely. 10. There exists, for 

 the above reason, no practical limit to the number of different 

 classes of sounds. 11. If an object is prevented from continuing 

 to vibrate, the sound is deadened, and where there is no vibra- 

 tory medium, as in a complete vacuum, no sound is producible. 

 12. The world of sound, unlike that of sight, is generally dis- 

 continuous, and generally presents a complex object by a vir- 

 tually single-featured sound; consequently the world of sound 

 is almost infinitely poorer in material presented than the world 

 of sight; this because sound depends on the sensible action 

 and vibration of objects, because such action is as a rule ex- 

 ceedingly rare, and because ordinary sounds are only heard 

 for a short distance. (Compare looking at a dog and listening 

 to his occasional barking, or looking at and listening to a cricket 

 match from a distance of a few hundred yards, but allow for 

 waterfalls, etc.) 13. Sounds, implying as they normally do 

 occasional action on the part of objects, form only a forward 

 time series as a rule, that is, we cannot ordinarily return to a 

 sound as we can to something seen. 14. Involving intermittent 

 action in objects, sounds generally take us by surprise. 



15. Diversity, frequency, and intensity of sounds, vary with 

 diversity, frequency, and intensity of vibration in an object. 



16. Certain classes of sounds are connected with certain classes 

 of objects (e.g., the sounds emitted by vibrating silver or gold). 



17. Knowledge of certain sounds is frequently connected with 

 certain known objects (e.g., a friend's voice). 



D. THE VOICE. 1. We possess a special organ for producing 

 sounds, the vocal chords. 2. Sounds form the chief means of 

 direct communication between men (and between most terrestrial 

 animals). 3. Speaking is guided by hearing, and hence when 

 hearing becomes disordered, speech also suffers. 4. Speech 

 for man is both active (speaking) and passive (hearing). 5. Sinde 

 it is in our power to generate sounds, we can hear sound at 

 will, provided a vibrant medium is present and we are not 

 forced into silence. 6. Experimental knowledge of sounds, re- 

 sulting from a certain deliberate activity of the vocal chords, 

 etc., should be allowed for. 7. "Silent" reading and reflecting 

 are usually auditive in character. 



E. IMAGERY, IMAGINATION, FEELING, INTELL1GENCE.- 

 1. Sound is second in order, sight being first, in respect of 

 the facility with which sensations can be imaged. 2. Subjective 

 sounds are represented by such sounds as singing in the ears 

 and hallucinations. 3. In growing tired or sleepy, and in 

 dreams, sound becomes either inaudible, or is disturbed or 

 distorted through misapprehension of its source. 4. Auditory 

 hallucinations are especially dangerous, because the origin of 

 sounds is usually problematical, sounds frequently breaking in 



