PANAMA  AND   SUEZ  CANAL  CERTIFICATE*

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provision on a national basis for the effective training of ship's
crews in boat work has, so far (1936), been established in the
United Kingdom.
PANAMA  AND   SUEZ   CANAL  CERTIFICATES.
Under Deck Tonnage is a measure of the internal space
between the top of the ceiling or double bottom in the hold and

Fig   4—Steamship in Canal Lock.
the under surface of the tonnage deck.   The unit of measurement
is a ton of 100 cubic feet.
Gross Register Tonnage is a measure of the total internal
volume of the ship, and is equal to the under deck tonnage plus the
tonnage of all enclosed spaces above the tonnage deck.