You can hear every slovo
When 100 years ago, was built Whispering Wall, no one knew about her amazing acoustic properties. The concrete dam across the river valley in South Parra Barbarossa built about 400 workers between 1899 and 1902 years. Dam closes with a huge reservoir Barbarossa 4515 megalitres of water, where the water comes in several districts in the south of Australia.
Whispering wall height of approximately nine-storey building - is the highest dam in the region. But the builders were not even aware of the properties of engineering marvel which themselves had created.
Since the dam is a rigid curved surface, any sound passes freely by its one end to the other. So you can talk with someone who is at the opposite end of platinum in 137 meters away from you, as if he is standing next to you.
Voices could be heard quite clearly by the so-called parabolic effect: the walls are so smooth, that is one sector of a circle, and the sound waves "bounce" off the wall several times, having reached such a way to the other end.
Properties Whispering walls were discovered by accident: According to local residents during construction were heard voices of workers who are on the other end of the dam complained about his boss. The discovery is truly amazing, but the jobs they save poor guy did not help.
If you go to Australia, be sure to check out the Whisper wall, here comes a lot of tourists every year. It is the perfect place for a picnic, and by the fact that in the district of pine forests, you can watch the birds.
via factroom.ru