Film, being light and small, can be sent rapidly to other places and used to print copies of the text where they are needed. Film images can also be projected easily on a movie or television screen. Television broadcasts are limited to an area that is within sight of the sending station or its relay . Although television relays are often placed on hills and mountains so that they can cover a wider region, they still can not cover more land than one could see from the same hilltop on a clear day. However, the rays also go out into the atmosphere, and if there is a relay station on a satellite that revolves around the earth, it can transmit the pictures to any point on the earth from which the satellite is visible. Three satellites permanently revolving over the equator transmit any television program to any part of the earth. This makes it possible for world editions of newspapers to give the news in all countries at the same time. Some day it may be possible for a subscriber to a televised newspaper to press a button and see a newspaper page on his television screen. He could also decide when he wants the page to turn, and, by dialling different numbers such as those on a telephone dial, he could choose the language or the edition of the paper he wants to read. It seems strange to think that, even today, methods of the past are not entirely useless. For example, sometimes press agencies that use radio and Telstar use carrier pigeons to send messages between offices in large cities because the pigeons are not bothered by traffic problems.
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