"It is more like a siren horn tooting up and down," laughed Nancy.
A spluttering crackle blotted out the wail.
"You would think they were frying doughnuts," grinned Dick, "wouldn't you?"
"And you really believe a thunderstorm would cause a noise like this?" queried Mrs. Crowninshield incredulously.
"It might. We have no way of knowing exactly what is raising the trouble."
"Do you mean to say that a storm that wasn't round here at all could——" burst out Jerry, then stopped embarrassed.
"Indeed it could," replied Bob, answering the unfinished question. "You see thunderstorms cause powerful electrical waves that affect apparatus miles and miles distant. Of course such waves vary in length but nevertheless they act on all aerials to a greater or less degree. Then, too, the atmospheric conditions are never quite identical, changing with the hour of the day, the season of the year, and local weather disturbances. Fortunately, since the air is positively electrified and the earth negatively, certain of these differences are remedied by the aerial that connects the two, the current discharges partially seeping off through the ground. Sometimes, however, in spite of every device used, such currents are strong enough to cause a roar in the receiver. In addition there is the interference from other radio stations which are busy transmitting messages, and although there are rules that aim to reduce this annoyance, it is, to a certain extent, always to be reckoned with."
"I should think somebody ought to invent something to prevent such troubles," declared Nancy.
"Why don't you, Sis?" asked Dick wickedly.
"But it is terrible to have the air so full of noise," continued the girl, as she made a little face at her brother. "I've always thought of the air as being still."