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No question is more important now than that of preserving durable peace.
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The properties of short waves are different from those of long waves. .
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A life raft made of rubber is more convenient than one made of wood.
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Then he showed me another telegram, the one received from the expedition. ; (), .
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1. The Great October Socialist Revolution linked the revolutionary struggle of the western proletariat with that of the oppressed people of the East. 2. The forces of peace are more powerful than those of war. 3. The industrial output of Austria in 1952 was nearly 10 per cent below that of 1951. 4. In 1951 the per hectare cotton yield in the USSR was nearly twice as great as that of Egypt. 5. The wages of the Europeans in South Africa are usually ten times as great as those of Africans. 6. One of Koreas acutest problems for centuries was that of water for irrigation purposes. 7. The first German edition of the Communist Manifesto was published in 1848; the first Russian one, early in the sixties.
1. An inert gas is the one which does not enter into chemical combination with other substances. 2. The most distant planets as well as the nearest ones are beyond the atmosphere of the earth. 3. The vegetation of valleys is richer than that of mountains. 4. The earliest squatting places of man in our country are those discovered in the Caucasus and in the Crimea. 5. Every useful object such as iron, paper, etc., may be regarded from a twofold outlook, that of quality and that of quantity. 6. A pure substance is the one containing no admixtures. 7. This radio set is much better than the one you showed me last time. 8. Markoni repeated Popovs experiments in London and built a radio apparatus which was an exact replica of the Russian one.
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II. , :
GENERATION OF STEAM
Steam is generated in a boiler by the application of heal to some part which is in close contact with the water it contains. The heat raises the temperature of the water to boiling point and eventually produces steam.
Sensible heat is the one added to the water during the period in which the temperature is rising and while no steam is being generated.
When boiling point is reached, the heat necessary to convert the water into steam is latent one and cannot be measured by the thermometer. Steam heated to a temperature above that which is necessary to make water boil at the given pressure is termed superheated steam.
The total heat of superheated steam is the one required to superheat to the desired temperature, plus to total heat of dry saturated steam above 32 Fahr., and at the superheated pressure.
When steam is generated in a closed vessel, the water and steam cannot be under the influence of the atmosphere, and therefore the pressure shown by the boiler is the pressure which differs from the absolute pressure by an amount equal to atmospheric pressure.
For practical purposes atmospheric pressure is taken as 15 lbs. per sq. in., and therefore the readings for the absolute pressure of steam in a boiler are 15 lbs. greater than those shown by the pressure gauge.
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