Anybody wanting more should check out “The Flute and Flute Playing” (1871) by Theobald Boehm - an autodidact polymath who employed his talents in metalworking and physics to iteratively perfect the metal cylinder bored flute.
It contains detailed explanations of his development process, including a complete schema for determining optimal tonehole positions - developed after he first created a flute in which he could move them!
It helped me to more deeply appreciate the engineering marvel that is the modern western concert ‘Boehm’ flute. It’s an exceptionally pure instrument.