To mark the centenary of London's Science Museum, 10 of the most significant objects in engineering, technology, science and medicine were selected. Almost 50,000 votes were then cast to rate the best invention.
In at No 10 is the electric telegraph. Two hundred years ago, people had to wait days, weeks or even months to receive letter sent via horse and ship.
Only 29 years after its first installation at Euston Station, this amazing new technology brought instant telecommunication on a global scale, with anyone in a large town able to send a message hundreds of miles in seconds, reaching every continent but Antarctica.