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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