Ғ. Н.Қисметова Ағылшын тілі грамматикасы

erecting the bridge. The designer has to calculate carefully how the various 
loads would be distributed and to decide which building materials are more 
suitable for carrying these loads.
TUNNELS
5. Tunnelling is difficult, expensive and dangerous engineering work. 
Tunnels are built to provide direct automobile orrailway routes through 
mountain ranges, under or over rivers.
They can also provide underground channels for water, sewage 
or oil. Befol'e the 19th century men had not acquired enough skill in 
engineering to carry out extensive tunnelling. Tunnels, however, were 
known in ancient times. They were, for instance, driven into the rock under 
the Pyramids of Egypt, and the Romans built one in Rome for their chief 
drain, parts of which still remain. One of the earliest tunnels known was 
made in Babylon. It passed under the Euphrates river, and was built of 
arched brickwork being 12 feet high and 15 feet wide.
Other ancient tunnels were built for water supply and for drainage.
7. Modern tunnels are often very long and deep. The Simplon Tunnel 
on the France-to-Italy railway, for example, is 12 miles long and in 
one place the peaks of the Alps rise over 6,000 feet above it. Some 
tunnels are over 50 feet in diameter. Many are circular in cross- 
section. Others are horseshoe-shaped, 7 with a level floor on which it 
is easy to lay permanent roads and railways.
UNIT 22
TUNNEL UNDER CHANNEL
1. "Will There Be a Tunnel under the English Channel?", "Tunnel - to Be 
or Not to Be", "A tunnel or a Bridge?"
articles with such headlines appeared in the press abroad. Englisll and 
French experts are considering projects created by the specialists of both 
countries. The authors of the projects offer diffel'ent solutions. One of 
them is a bridge/tunnel combination.
A tunnel undel' the English Channel was first suggested in 1856. It was 
agreed in 1875 to build it and work was actually begun. However, the 
British War Office objected that an enemy on the European mainland 
could easily invade England through such a tunnel, and the British 
Government objected to the scheme.
In 1957 interest revived in the idea of a Channel Tunnel and the question 
was studied afresh by a group of French and British engineers. Such a
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Tunnel between Dovel' and Sagatte would have a length of about 36 miles 
of which 24 miles
i would be under the sea, and would run through a layer of
I dense chalk which is known to be free from cracks and allows I water to
penetrate it slowly. It would probably have to be a I twin railway tunnel.
There are several difficulties in having I a road tunnel of this length, the
chief of which is the enormous cost of ventilating it. Total cost is estimated
at between 450 and 560 m illio n dollars, to be shared by Britain and
France with possibly some other European country.
No dates have so far been mentioned definitely but it might be completed 
at the end of our century.

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