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Our Surroundings 



Keystone View Company. 



A PICTURE SENT BY TELEPHOTOGRAPHY 



This picture shows the damage done to an apartment building in Austria during a 

 civil war. The picture was sent by wire from Vienna to London and by radio from 

 London to New York. Notice the blurred effect, a characteristic of pictures sent 



by telephotography. 



train, it would have taken nearly a week. Magic? No, tele- 

 photography! 



Telephotography is the sending of pictures by telegraph or 

 radio. This is done with the help of a machine consisting of a 

 revolving cylinder, a lamp, and a photoelectric cell. The picture 

 to be sent is fastened to the cylinder, and a small beam of light 

 from the lamp is focused on one corner of it. On some machines 

 the cylinder is mounted on a spiral screw, so that as it revolves 

 it also moves along the screw. In other cases the lamp and the 

 photoelectric cell are mounted on a spiral screw and move along 

 the screw as the cylinder revolves. The beam of light thus travels 

 continuously over the surface of the picture until all parts of 

 the picture have been illuminated. 



As the cylinder revolves, the beam of light from the lamp is 



