The classic "overbalanced wheel" perpetual motion machine, as designed by French Architect Villiard De Honnecourt in about 1235, and studied extensively by Leonardo Da Vinci in the late 1400's.
$98.00 more info
It was invented in China, about 2600 years ago, and is one of the most precise machines in ancient history. It is a non-magnetic compass, and the oldest example of differential gearing in the world.
$59.00 more info
The Medieval Battering Ram was an awesome force in ancient times. With it, a small group of men could easily bust through the portcullis and gates of virtually any castle.
$34.95 more info
No glue! The unique structure of this bridge holds itself together without any fasteners or connectors.
All parts are precision cut from high-quality
hardwood.
The finished model is 36” wide, 10” tall and 5-1/2”
wide.
$21.95 more info