ANSWERS to Mystery Questions of the Week - 4-06-2009

From Monday's posting

ANSWERS:

1 - What indirect connection, mentioned inside the book, could account for the title Submarine?

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(Quotation from book) You know they used ultrasound during World War Two to detect submerged objects, I say.

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2 - What did the early development (of ultrasound) share with an element, much in the news lately, Polonium? (note: Polonium was incorrectly typed as Plutonium in the original question).

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(Quotation [color added]) 1880 - The scientist, Jacque Curie, the man who discovered element polonium and major parts of radioactivity, and his brother Pierre research sound waves. They develop the principle of piezoelectricity which eventually led to the creation of the transducer. (here ) Also:

Early 1900s - A group led by Paul Langevin experiments with high frequency ultrasound. They use this to detect submarines, which later led to the development of sonar.

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Submarines are always silent and strange.