“What on earth is that?” asked Tom’s mother, when finally the new idea had assumed concrete form and she was invited to witness a demonstration. “It looks like some sort of a huge birdcage,” she continued as she seated herself and
glanced at the wooden framework wound with wire that stood on a small table.
“Well, I don’t suppose you can understand,” replied Tom, with the superior air of one who is master of an art beyond ordinary comprehension, “but I’ll try to explain. That’s a loop aërial.”
“But I thought the aërial was that wire clothesline-like affair on the roof,” objected Mrs. Pauling. “You see,” she laughed, “I am beginning to learn a little.”
Tom grinned, “Oh, yes, that’s an aërial, too,” he replied. “But this is another kind. With this we don’t need any ground or lead-ins or lightning switches. And it’s directional too. That is,” he hastened to explain, “by turning it one way or another we can pick up signals from certain directions and not from others. Some people call them compass aërials and they’re used on ships for locating other vessels or for finding their way. And besides, they cut out a lot of static.”
“Now please, Tom, what is all this you’re talking about? What is static?”
“Well that’s mighty hard to explain,” said Tom, scratching his head reflectively. “It’s a sort of
electricity in the air—lots of it around when there are thunderstorms and lightning.”
“Lightning!” exclaimed his mother. “Do be careful, fooling with all these things, Tom. I’m always afraid you’ll get a fearful shock or something.”
“Nonsense,” laughed Tom. “Static doesn’t hurt any one and lightning won’t do any harm. An aërial is just like a lightning-rod and if it’s struck the lightning is just carried down to the ground harmlessly; but this loop aërial’s different. Now let’s hear how it works.”