permitted larger ships to use them and to make loading and unloading more
quickly.
7. Improvements introduced in the 20th century included the
smoother and more efficient type of engines cal led steam turbines and the
use of oil fuel instead of coal. Between 1910 and 1920 the diesel engine
began to be introduced in ships. These diesel-engined ships are called
motor ships.The largest ships, however, are
s till generally driven by
steam turbines. In the late 1950s a few ships were being built which were
equipped with nuclear reactors for producing steam.
8. In 1957 the world’s first atomic ice-breaker was launched in
Leningrad.
This atomk ice-breaker is equipped with an atomic engine owing to which
her operating on negligible quantities of nuclear fuel is possible. In spite of
the capacity of her en' gine being 44,000h.p. it wil 1 need only a few grams
of atomic fuel a week. .
The atomic ice-breaker has three nuclear reactors.
The operation of the
nuclear reactor is accompanied by powerful radiation. Therefore, the ice
breaker is equipped with reliable means of protection. The ice-breaker is
designed for operation in Arctic waters.
9. Canal Transport.- Sea-going ships can use some rivers, such as the
Thames in England, the Rhine, and
the Volga in Europe and the
Mississippi in the United States. Generally, however, a riv e r has to be
"canalized" before ships can use it. This means widening and deepening
the channel and proteeting its banks so that they do not wash away and
bloek the river with mud.
10. We find the British canals to be quite narrow and shal low.
The canals in Europe are much larger than those in Great Britain. Franee
has
a big network of canals, centred on Par is, and linking ports of the
Atlantic, Mediterranean and English Channel coasts with each other and
with other countries.
In the USSR canals large enough to be used by
ships link Moscow with
Leningrad on the Baaltic Sea. Other Soviet canals run between the White
Sea and the Baltik, and Between the Don and the Volga rivers.
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