"Java Jive" wrote in message
...
On Mon, 31 Aug 2009 23:16:24 +0100, geoff wrote:


Another was to get an old can, not one that contained anything highly
flammable, something like olive oil would do. Put a centimetre or two of
water in the tin, and boil it until steam is coming out of the top.
Then turn off the gas, and quickly, using oven gloves, replace the lid
making sure it's tight. Stand back and wait. After a while, the can
crumples.

EXPLAIN

Steam drives out the air, seal lid, steam returns to water leaving a partial
vacuum in the tin.

Outside air pressure now greater then inner air pressure and tin crumples.

Used to do it with 5 gallon cans in school.

Gander.