In article ,
zxcvbob wrote:

BobR wrote:
In theory if you could find a material that would block magnetic
forces, you could in fact create a machine that power itself without
any outside source of power. The problem is in finding a material
that can block magnetic fields and to my knowledge no such material
exists.

Bismuth, or any superconductor. HTH :-)

Bob

OK, I picked up a can of bismuth and some magnets. Now where are those
plans for my free energy device?