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Energy and Electronics (Atroshkina A.A.,etc.).doc
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The use of electromagnetic waves

Many experiments having been conducted to discover the best types of radiation, a lamp producing sterilizing radiation was developed. The lamp has been applied to surgery, the radiation having been shown to be harmless to human flesh. By bathing the operating table in the rays it is possible to ensure sterility, its principle being the exclusion of germs in the modern operating theatre.

An interesting use is made of the longer waves. Waves between 10 and 100 miles in length can he used for melting metals without flame. The metal is placed in a cruicible which is inside the solenoid originating the waves. The latter being led into the metal, their absorption sets up secondary currents which result in heating the metal to such an extent that it melts. The coil carrying the current remains quite cold. One of the advantages of this apparatus is the case with which metals can he melted when the exclusion of air is necessary.

On the same principle it is possible to cook a dinner in a cold oven. A kettle may be boiled on ice. Some years ago there was a demonstration in which a beefsteak was frozen into a block of ice. Wireless waves were then passed and the meat was completely cooked without the ice being melted. In the same way fish were cooked in water, the water remaining perfectly cold.

Very long electromagnetic waves are also employed for examining the structure of the earth. The waves having a length of about 25 miles are sent downwards. When encountering metallic ore they are absorbed and an electromagnetic field is set up. This can be measured on the surface of the earth and as a result of these measurements it is possible to indicate the direction and depth of the ore. This method is now frequently used in geophysical prospecting.

The “radio knife” can be described here. In the so called “radio knife” the heat is developed at the point of a needle acting as one of the electrodes, and becomes so great that the tissue is burned or cut. The electrode cuts as cleanly as an ordinary surgical knife, with the added advantage that the heat seals the tissues of nerves it is cutting reduces shock, prevents bleeding and makes for easy healing. This knife is not suggested to take place of the scalpel for all operations, but no doubt it is of special value in certain fields, such as that of brain surgery.

Notes:

  1. surgery …………………...

  2. by bathing the operating …

table in the rays

  1. germs ……………………

  2. the operating theatre …….

  3. flame …………………….

  4. cruicible …………………

  5. coil ………………………

  6. the exclusion ……………

  7. oven …………………….

  8. kettle ……………………

  9. to boil ……………………

  10. to freeze …………………

  11. wireless ………………….

  12. to encounter ……………..

  13. radio knife ……………….

  14. needle ……………………

  15. the tissue ………………...

  16. to seal ……………………

  17. bleeding …………………

  18. to make for ………………

  19. healing …………………..

  20. brain …………………….

хирургия

облучая операционный стол

микробы

анатомический театр

пламя

тигель

катушка

исключение

печь

чайник

кипятить

замораживать

радио

встречать

электронож

острие

ткань

запечатывать

кровотечение

способствовать

заживление (раны)

мозг

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