HOW DID THE FIRST PHONE CALL WORK?
Sandra Camado
Alexander Graham Bell’s big breakthrough came on 10 March 1876 when he used what he called a ‘liquid transmitter’. This was a vertical metal cone with a piece of parchment stretched like a drum over its narrow end at the base. On the outside of the parchment, Bell had glued a cork with a needle stuck in it, pointing into a tiny cup of diluted sulphuric acid.