It was the 4th of August 1945. The European chapter of the Second World War was over.

The USA and USSR pondered their future relationship. At the American Embassy in Moscow, the

group of boys from the young pioneer organisation of the Soviet Union made a charming gesture of friendship

between two superpowers. They presented a large, hand-carved ceremonial seal of the United

States of America to Averall Hariman, the US ambassador. It was later to become known, simply

as the thing. Naturally, Hariman's office would have checked the heavy wood ornament for electronic

bugs, but with neither wires nor batteries in evidence, what harm could it do?

Hariman gave the thing pride of place, hanging on the wall of his study. From where, it betrayed

his private conversations for the next seven years. He couldn't have realised that the device had

been built by one of the true originals of the 20th century.

Leon Thereman was famous even then for his eponymous musical instrument. He'd been living in the US with his wife

Lavigne Williams before returning to the Soviet Union in 1938. Kidnapped, she said. In any case,

he was promptly put to work in a prison camp, where he was forced to design among other listening

devices, the thing. Eventually, American radio operators stumbled upon the US ambassador's

conversations being broadcast over the airwaves. These broadcasts were unpredictable, scan the embassy

for radio emissions and no bug was in evidence. It took yet more time to discover the secret.

The listening device was inside the thing, and it was ingeniously simple. Little more than an antenna

attached to a cavity with a silver diaphragm over it, serving as a microphone. There were no batteries

or any other source of power. The thing didn't need them. It was activated by radio waves

beamed at the US Embassy by the Soviets. At which point it would broadcast back using the energy

of the incoming signal. Switch off that signal, and the thing would go silent. Much like Leon Thereman's

unearthly musical instrument, the thing might seem a technological curiosity. But the idea of a

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