Prince Rupert's drops
The Fibonacci sequence generates from the addition of the two preceding terms, and its ratio approximates a proportion that exists as a dynamic equilibrium, at root of much that is beautiful.
Comma of Pythagoras
The ratio of 12 perfect fifths and 7 octaves: 1 to 1.0136...
7 octaves: 128.00 12 fifths: 129.746337890625