Spinning around
Still spinning around
At rest
Ok its not a conventional steam engine; but it works 
The device is what is known as an æolipile (or hero's engine) & basicly works by propelling itself around on two jets of steam.
-As the water heats up it produces steam, this the causes pressure to build up & so the steam is forced out the nozzles on either side of the tin. As it leaves this literaly blows the device round!
Anyways more can be read here:
http://en.wikipedia.org/wiki/Aeolipile
