Ingenium

Five Machines That Changed the World

Ingenium is medieval English vernacular for "an ingenious contrivance". I have
analyzed five of these contrivances in this, my first book. We see why the 
longbow is such an efficient weapon. The waterwheel was humankind's main source 
of power for at least 1,500 years. It was supplanted by James Watt's 
high-pressure steam engine--why was this design better than the earlier 
atmospheric engines? The trebuchet (shown above) was medieval heavy artillery. 
These siege engines were powered by gravity, in contrast with the torsion engines
of antiquity, such as the Roman ballista. Lastly, the pendulum clock anchor 
escapement led to much more accurate timekeeping than the earlier crown
escapement. The history is presented along with the physics.

Ingenium (2007) is published by Johns Hopkins University Press.