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SUNDAY SHOW & TELL
vol.78

Have you ever wondered what keeps a bicycle upright, or how a riderless bike can travel a solid distance without falling? Some feel they understand the basic physics involved, but the true answers might surprise you. Take a minute to learn something new.

THE PHYSICS OF A BICYCLE (video)

Ten years ago, Rob McBride, an IT specialist from Shropshire, England, was saved by a newfound fascination with trees. Now, he returns the favor by participating in Ancient Tree Hunt, an effort to catalogue and preserve the oldest trees in the UK. Read his inspiring story below.

TREES SAVE A MAN, MAN SAVES THE TREES (photo essay)

The future has arrived! Imagine never again having a flat tire, or needing to change one. The Energy Return Wheel, an airless prototype, offers that possibility and so much more. Check it out!

ENERGY RETURN WHEEL (article)