A siren whistle that kills flies and mosquitoes in ten seconds is described in (he Journal of the Acoustical Society of America, The whistle is hooked to a horn, that directs the sound. But don't make one yet. It has to be almost as close to the fly as a swatter. If you started whistling the flies to death, you soon would become dizzy and probably start seeing double.
The human risks of this whistle are new to science. The scientists are hunting for some sort of a loud-speaker to kill crop insects.
The siren makes a noise too high-pitched for human ears to hear. But after a little while a person close to it gets dizzy. He does not have to be in the sound stream—in fact, if any part of him is directly in the beam of sound, close up, that part gets very hot. If a hand is placed in the stream, with fingers touching, the places where they touch become burned. The temperature at these flesh contact points jumps to more than 150° Fahrenheit.
Workers spending an entire day in the state college whistle room report that they become more than ordinarily tired. Those who open their mouths while the whistle is blowing feel a cool tickling sensation in their mouths. Some like this tickle,
The reasons for these effects are not known, except the burning. The whistle kills the insects because the sound waves overheat their bodies. It heats anything the sound blast touches. These burns kill cockroaches and caterpillars in three to four minutes. The roaches used were about two inches long. White mice died in one minute from the sound bums, except one mouse which was shaved. Naked, he lived more than, two minutes. The reason was that fur traps the heat faster.
All this makes me think of what the Bible says of the sound of a shaken leaf:
And upon them that are left alive of you I will send a faintness into their hearts in the lands of their enemies; and the sound of a shaken leaf shall chase them; and they shall flee, as fleeing from a sword; and they shall fall when none pursueth (Leviticus 26:36).