barrel (storage)

A barrel or cask is a hollow cylindrical container, traditionally made of wood staves and bound with iron hoops. Someone who makes such barrels is known as a cooper. Contemporary barrels are also made in aluminium (also called kegs) and plastic.Barrels often have a convex shape, bulging at the middle. This constant bulge makes it relatively easy to roll a well built wooden barrel on its side, changing directions with little friction. It also helps to distribute stress evenly in the material by making the container more spherical.Casks used for ale or beer are equipped with shives, spiles and keystones in their openings.
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