Fig. 135.
Ships in the harbor of Naples.
In the background is Mt. Vesuvius.
CHAPTER FIFTEEN
THE USE OF SHIPS
Not many decades ago, wooden sailing vessels carried the whole of
the world’s commerce on the high seas, but now steel steamships carry
the greater part of it. In almost every large harbor a few sailing ves-
sels may indeed be seen ; they are still extensively used to carry heavy,
bulky goods, such as jute from Calcutta, grain and lumber from the
west coast of North America, and nitrate of soda from Chile. But
many of the sailing vessels now built have auxiliary steam power to
take them through calms and into harbors. Only in small harbors or
for the purposes of purely local trade is the wooden vessel still the prin-
cipal carrier.
OCEAN TRAFFIC
No civilized country produces a sufficient variety of goods to satisfy
all its own needs; every such country must draw upon other parts of
the earth. Since three fourths of the earth’s surface is water and the
other fourth consists of detached land masses, the commodities from
distant lands generally have to cross the water. If there is a choice
between a land and a water route, the water route is generally chosen,
because it is cheaper.
How ocean liners differ from tramp steamers. Just as express
trains and locals, fast freights and slow freights, all run on the same
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