That means that an object under the stack - in the team's experiments, a block of wood about 10cm long - would not "hear" the sound, and any attempts to locate the object using sound waves would not find it.

BBC: Acoustic 'cloaking device' shields objects from sound

After Emily hit upon the fossil with a spade, her father and palaeontologist Dr Neville Hollingworth helped her dig out the block of mudstone the 162.8 million-year-old object, which had spikes to ward off predators, was encased in.

BBC: Children discover 'rare' fossils at Cotswold Water Park

The Germans and French object, for instance, to recent decisions by the commission to enforce competition policy and block subsidies.

ECONOMIST: European Union