Английский язык. Жесткова М.В - 67 стр.

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67
13) termination
m) штанга токоприёмника (троллейбуса)
14) trolley pole
n) дистанционное управление
15) tunneling shield
o) избрать кратчайший путь
16) underpass
p) опасность затопления
17) wooden shuttering
q) загрязнение воздуха
Part 1
Depending on where in the world it is located, an underground electric-railway system may be
called a subway, underground railway, tube, or metro. The underground railway is the quickest,
safest, most reliable and comfortable means of city transport. Metro can solve the problems of
carrying a great number of passengers within urban and suburban areas as well as the problems of
traffic jams, air contamination and noise.
Subways are usually built under city streets, but in order to take shortcuts they often must pass
under rivers. From the technical point of view the underground railway system is very expensive
and complicated constructional work. This system includes subsurface lines, ground based lines and
elevated lines. Ground based lines are usually used at the terminations of the underground railways.
Outside the immediate downtown area, the subway lines usually emerge above ground too,
resembling conventional railways or elevated transit lines. Besides, the underground and surface
structures involve stations, tunnels, escalators, underpasses, ventilation and sanitary engineering as
well as a power supply system.
The permanent way of underground railways differs from the normal railway track. The sleepers
are only 0.9m long. They are shorter than those of the railroad track which are 2.7m long. The
sleepers of the normal track are laid upon ballast made of broken stone or other materials. The
crossties of the underground railway are laid directly on concrete base. It is more expensive but
keeps air free from dust. If the ballast were made of slag, gravel, sand or even broken stone, the train
would be followed by the dust clouds.
Modern Metro trains are powered by electricity. The current is obtained from the third rail. This
contact rail is laid along the whole track and transmits the direct current of 825 volts to the train
electromotor through the pantograph.
The Underground carrying capacity depends on the number of coaches which ranges from 2 to 8
per train and the frequency of train running which ranges from 80 seconds to 10 minutes.
Part 2
Nowadays there are underground railways in 80 cities all over the world. The construction of the
first subway system, called the Metropolitan Railway, began in London in 1860. It was built by the
so-called cut-and-cover method – that is, trenches were dug along the streets, reinforced with brick
sides, and roofed with girders or a brick arch. The roadway on top was then restored. The
Metropolitan line was opened on January 10, 1863. It used steam locomotives, not electric power.
In 1866 excavation began for a second subway line of the London Underground. It was built
using a device called a tunneling shield that allowed a tunnel to be driven under the Thames River
without the danger of flooding. The tunnels were driven deep enough to avoid disturbing public-
utility works, or the foundations of buildings, and there was no disruption of street traffic. The
Tube—the first electric underground railway—began operation in 1890.
In the same decade, many other cities followed London's lead. In Budapest an electric subway
was opened in 1896 that used single cars with trolley poles. It was the first subway on the European
continent. Because the tunnels were flat-roofed instead of arched, the original trenches were
shallower than those of earlier lines. As a result, the subway construction was far less costly.
In Paris, construction of the Métro (Chemin de fer métropolitain de Paris) was begun in 1898,
and the first 6 1/4 miles (10 kilometers) were opened in 1900. Its rapid construction was made
possible largely by improved cut-and-cover methods. Vertical shafts were sunk at intervals along the
planned route, and from these shafts side trenches were dug. Masonry foundations to support

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