I just got this book:
http://www.howround.com/

a must to all math/engineering lovers.

if you didn't realize it yet, I strongly recommend it (if my word is worth something...)

ND.

I'm wary of many Café recommendations, but a recommendation from Nir
is gold.

Stan

You can read part of the first chapter before you buy at amazon. (at least you can at amazon.co.uk). Looks interesting.

It seems from the webpage that the book is all about different mechanical models. It does contain a fair amount of geometry and math.
It urges you to build the models presented and gives you some great historical backgrounds on the necessity of the mechanical inventions.

It also discusses the difference between ideal mathematical concepts and real world engineering requirements which sometimes need not be as harsh as the ideal solution.
e.g. the necessity to come up with a machine that generates straight motion from a circular motion. James Watt developed his linkage which is not a true straight line motion but pretty darn close. http://en.wikipedia.org/wiki/Watt%27s_linkage
click on the animation at the right to enlarge.

Really cool stuff in this book and I am only at chapter 2!

ND