Leonardo DaVinci's Self-Supporting Arch Bridge
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.
$29.95 more info
Medieval Battering Ram
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.
$39.95 more info
The Lever Paradox
When discussing levers, Archimedes said: "Equal
weights at unequal distances are not
equilibrium." unfortunately, Archimedes never saw
our Lever Paradox, where equal weights at unequal
$49.95 more info