Sound factsUnited Kingdom quiz
This strange object was built on the coast of Great Britain. What is it?
Acoustic mirror. Prior to World War II and the invention of radar, acoustic mirrors were built as early warning devices around the coasts of Great Britain, with the aim of detecting airborne invasions. The development of radar put an end to further experimentation with the technique.
Which reptiles roar?
Crocodiles have vocal cords in the larynx and are the only reptiles able to produce guttural roars.