[MKSheppard]

http://www.spanamwar.com/olympiatourbunker.htm

quote:

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The coal that was needed to power OLYMPIA
was stored in coal bunkers. Coal bunkers
were large compartments in the ship that
were simply storage rooms used strictly for coal. These storage rooms were arrayed on
the ship in a way that allowed them to
function as additional armor. They were
placed along the hull, to protect the more
vital inner areas, such as the engine rooms
and boiler rooms, in case of attack. The
thought was that if the ship took a hit, the
projectile or torpedo would explode on
impact with the coal in a coal bunker, if
it did explode when it hit the hull. The
mass of coal would protect the inner
portions of the ship, and the coal bunker
could simply be sealed off to stop the
flooding.

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