Chapter 1 - Tuning and temperament: closing the spiral
Pythagoras discovers the Pythagorean scale with the pitches made from the hammers from a blacksmith forge. This scale is the current scale used in the Western Hemisphere, in this pattern C-D-E-F-G-A-B-C. The number for the intervals of this scale is not evenly distributed, for if it was many tones would sound out of tune.
Chapter 2 - Music cosmology: Kepler and his readers
The pieces composed by Kepler show his ability to be outdated or be in style centuries later.
Chapter 3 - The science of musical sound
The sound of music is quite hard to graph, but humans aurally receive the music in such a way that has yet to be scientifically shown.