   Way back in the 17th Century German scientist Otto von
Guericke demonstrated the power of vacuum forming by joining two
steel half domes that two teams of horses pulling in opposite
directions could not pull apart. In this video, MAKE
Contributing Editor William Gurstelle recreates the experiment
with two cake pans. And you can, too, in this easy to follow
experiment.     1. Keith Neufeld says:      This is about the
power of vacuum, not the power of vacuum forming, yes?    2.
Jeremiah Johnson says:      The spheres were copper, not steel.