Elegance In Science
Ian Glynn, Multco Central, 501 G568e 2010
Clever reasoning and design of experiments, mostly.
- p30 Kepler realizes that Mars has a 687.1 day orbital period, and combs through Tycho's measurements of Mars to find observations that are close to 687.1 days apart, using that position as a fixed reference point (and the fixed stars) to determined the orbit of the Earth. With the Earth's orbit determined precisely, he precisely determined the orbits of Mars and other planets.
p31 First law ellipse made Kepler uncomfortable, second law angular momentum, third law period T2 = Semi3
The rest is mildly amusing, I did not read the entire book.