PORT ECONOMICS
is raised above water surface level, so exposing its entire
under surface and enabling repairs to be carried out in the
open.

The two principles of the dry dock and the floating dock,
as adapted for shipping repairs, are entirely distinct. The
one is a structure consisting of a substantial shell, or lining,
to an excavation in the solid earth, and the other, a hollow
structure of iron or steel, floating in the water. Both

VESSEL IN DRY Dock (DUNKIRK)
systems are in common use for carrying out repairs to
vessels of the largest size, and there are advocates for each.
RELATIVE MERITS OF DRY AND FLOATING DOCKS

The following are some of the arguments urged for and
against the respective systems. On the whole, they are
fairly equally balanced, though, by reason of circumstances,
it will often be found that there is some paramount con-
sideration which enables a preference to be determined.

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