A man sitting quietly before his fire may be at peace, but he is not at rest. If he sits long enough:
1) He turns a gigantic somersault, once every 24 hours, because of the earth's daily rotation on its axis. If he lives half way between the North Pole and the Equator, this motion carries him along along at some 700 miles per hour.
2) The earth's annual revolution around he sun swings him in an orbit nearly 200,000,000 miles across at a speed of 18 miles per second.
3) The movement of the...