Chapter III: Book IV

THE PHILOSOPHY OF THE SECONDARY MECHANICAL SCIENCES.

CHAP. I. OF THE IDEA OF A MEDIUM AS COMMONLY EMPLOYED 293

_Art._ 1. Of Primary and Secondary Qualities.
2. The Idea of Externality.
3. Sensation by a Medium.
4. Process of Perception of Secondary Qualities.

CHAP. II. ON PECULIARITIES IN THE PERCEPTIONS OF THE
DIFFERENT SENSES 302

_Art._ 1. Difference of Senses.

_Sect._ I. _Prerogatives of Sight._
_Art._ 2. Position.
3. Distance.
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_Sect._ II. _Prerogatives of Hearing._
_Art._ 4. Musical Intervals.
5. Chords.
6. Rhythm.

_Sect._ III. _The Paradoxes of Vision._
_Art._ 7. First Paradox.
8. Second Paradox.
9. The same for near Objects.
10. Objections answered.

_Sect._ IV. _The Perception of Visible Figures._
_Art._ 11. Brown's Opinion.

CHAP. III. SUCCESSIVE ATTEMPTS AT THE SCIENTIFIC
APPLICATION OF THE IDEA OF A MEDIUM 322

_Art._ 1. Introduction.
2. Sound.
3. Light.
4. Heat.

CHAP. IV. OF THE MEASURE OF SECONDARY QUALITIES 333

_Sect._ I. _Scales of Qualities in General._
_Art._ 1. Intensity.
2. Quantity and Quality.

_Sect._ II. _The Musical Scale._
_Art._ 3. Musical Relations.
4. Musical Standard.

_Sect._ III. _Scales of Colour._
_Art._ 5. The Prismatic Scale.
6. Newton's Scale.
7. Scales of Impure Colours.
8. Chromatometer.

_Sect._ IV. _Scales of Light._
_Art._ 9. Photometer.
10. Cyanometer.

_Sect._ V. _Scales of Heat._
_Art._ 11. Thermometers.
12. Their progress.
13. Fixed Points.
14. Concordance of Thermometers.
15. Natural Measure.
16. Law of Cooling.
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17. Theory of Exchanges.
18. Air Thermometer.
19. Theory of Heat.
20. Other Instruments.

_Sect._ VI. _Scales of other Quantities._
_Art._ 21. Tastes and Smells.
22. Quality of Sounds.
23. Articulate Sounds.
24. Transition.