Английский язык в сфере профессиональной коммуникации: природопользование. Тарасова Л.А - 31 стр.

      There is regular exchange of information between the «tsuna-
my» study centres in Sakhalin and Honolulu. Sakhalin transmits data
from observes in Kamchatka and the Kuril islands. These lie in a zone
where four-fifths of all earthquakes in the world occur. These earth-
quakes sometimes originate only 100—125 miles from Russian shores,
a distance a tidal wave can cover in 20—30 minutes.
      But Russian stations give warning of possible danger within
seconds of the quake.




                                 Unit 8
                    PROPERTIES OF AIR

      Air is the gas which we know best, and, in discussing gases,
we shall use it as an example. You must remember, however, that
the laws that apply to air apply to all other gases.
      Air has weight. We can easily show it if we weight an incandes-
cent lamp. Heat a spot on the lamp red hot, using a mouth blow-
pi pe. The air pressure will make a hole through the glass and the
lamp will fill with air. Weight it again and you will find that the
lamp weights more, than before, because it is now full of air. Fill
the lamp with water and find its volume. Now you have all the
fiûgures necessary to determine the weight of one cubic foot of air.
Thus we know that the weight of a cubic foot of air at 0°C and 76-cm
pressure is .081 pound, or 12 cubic feet of air weight a pound.
      Since air has weight, it must press down on the surface of the
earth. At sea level the pressure of the air on the surface of the earth
is about 15 pounds per square inch. We often call this pressure of
15 lb. per sq. in. a pressure of one atmosphere, but the figure 15 is not
exact because the pressure varies with the level of the place and the
height of the barometer at that time.
      Although we cannot see it, there is air all around us. If you
move your hand in front of your face, you can feel the air moving
as your hand pushes through it. Blow on your hand and you will feel
the air coming out of your mouth. We could not live without air. We
take it into our bodies blowing it out again through our noses and

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