MathOfTheWesternMusicalScale
There's a decent article in issue 4 of the Napalm e-zine
on Just Intonation and the western scale in general:
http://napalm.firest0rm.org/issue4.txt
It describes what makes a chord sound in tune to our ear, the
logarithmic nature of our perception of sound, and how we
went from just intonation to the less precise compromise of the
modern scale. Pending their permission, I'll post the entire article text here.