EXPLANATION OF TERMS USED
has been entirely superseded by the term wet dock; a
floating dock now signifies something very different, as
will be seen below.

A Dry Dock! is the converse of a Wet Dock, and in this
country means a chamber, the floor and sides and one end
of which are lined with watertight material, such as stone
or concrete, and the other end provided with a pair of
gates, caisson, or other means of closure, for the purpose of
excluding the water during such time as the dock is occupied
by a ship for the purpose of undergoing repairs. Such
docks do not, of course, attain anything like the dimensions
of wet docks, being constructed generally for the reception
of a single ship, whereas wet docks and basins provide
simultaneous accommodation for a great number of craft
of all kinds.

The dry dock is often referred to as a Graving Dock, the
original word, ‘ graving” (engraving), being applied to
the process of scraping, cleaning and painting, or tarring,
the underside of a vessel's hull. But as much more
extensive overhauls than this, and repairs of a very im-
portant character, are carried out in dry docks, the latter
term has come more generally into use than the other as
indicating the wider range of service.

A Floating Dock is, as the name implies, a dock structure
able to float. It is generally constructed as a series of
pontoons or chambers, which can be emptied of water so
as to provide the necessary degree of flotation. Essentially,
a floating dock consists of a floor or platform, with two
side walls, all of steel framing and plating, upon and
between which the ship is berthed. When the platform
has been sunk to a sufficient depth to allow the vessel to
float upon it, the pontoons are pumped out and the vessel

1 In America, the term ““ Dry Dock ” is also understood to include
the Floating Dock, described in the next section. Sometimes, then
but not invariably, the qualification * Floating ”” is added. For
the purpose of avoiding confusion, the author thinks it would be
better to adhere to the clear distinction between the two structures
which is drawn here.

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