Did you know that there is a tower in Chester which was used to create perfectly spherical lead balls for muskets?
A simple idea, take molten lead to the top of tower, tip it down tower allowing it to fall through a number of sieves until it lands in a large pool of water.
More info information available on it here:
Now it is the heart of a redevelopment plan for the canal side in Chester. Chester Chronicle
The Grinch Manifesto 