In 1953 Robert Dotzauer of Los Angeles in California, successfully balanced three lawnmowers on his chin,
which with a combined weight of 145 pounds, weighed five pounds more than he did.
Comedian Mark Faje also balances lawnmowers on his chin, but only one at a time.
The difference is that Mark’s lawnmower is motorized and running.
What is echolocation,
Dolphins, shrews, and most bats and whales use echolocation to navigate and hunt.
These animals make sounds, then wait to hear its echo.
The length of time between sound and the echo shows how far away an object is.
The slight time difference before the echo reaches each of the animals ears indicates direction.
Dolphins have especially sensitive echolocation systems and can tell the difference between similar objects, even in a noisy environment.
Out Of The Dark,
” I am not blind, I just can’t see “, says Ben Underwood, who lost his eyes to cancer at the age of three.
As Ben zips around fearlessly on his Roller blades, rides a bike, and plays football and basketball, the only sign that he is not just an average Californian teenager is the constant clicking sounds he makes.
Aged five, Ben discovered that he could find his way around by making noises with his tongue.
Now he ” sees ” with his ears, using echolocation, just like bats and dolphins,
Echoes can give detailed information about the size and location of objects, and the type of sound gives further clues-a sharp echo indicates glass, for example.
By putting all the information together, Ben is able to build up a picture of his environment.
Scientists have discovered that the part of the brain that processes visual images does not stop working when people lose their sight and it can be activated by other senses, such as touch or hearing.
One of the earliest known cases of human echolocation is that of British navel lieutenant James Holman ( 1786 – 1857 ),
who traveled the world on his own, using the sound of a tapping cane to get around, after losing his sight at age of 25.