We just learned about the Rotative Beam Engine.
Another part of the early steam engines is the Sun and Planet Gear.
After the rotative beam engine came up with a way to have a beam go up and down and spin a wheel around,
it was hooked up to a type of gear called a sun and planet gear.
It was called that because one gear goes around the other, kind of like a planet going around the sun.
(from: wikipedia - sun and planet gear)
Kid Facts - Blast from the past: Forensic Entomology
