sorry to be a pedant
and i appreciate the irony of arguing this point, but i reckon you could make a concrete canoe
( ,
Fri 19 Nov 2010, 10:18,
archived)
I don't know the displacement of water would be lower then the mass of the canoe
unless it was a massive fucking canoe
( ,
Fri 19 Nov 2010, 10:24,
archived)
Britain and the US had fleets of
concrete ships during the war when steel and iron were needed for armaments.
en.wikipedia.org/wiki/Concrete_ship
( ,
Fri 19 Nov 2010, 10:54,
archived)
en.wikipedia.org/wiki/Concrete_ship