Poulsen's Telegraphone, 1903.
© Science Museum / Science & Society Picture Library
Valdemar Poulsen (1869-1942), Danish inventor of magnetic recording, produced his first machine, a magnetic version of phonograph using a cylinder wrapped with steel wire which became magnetised. He later used reels of wire for recording incoming calls. Poulsen's machines were probably unreliable and complicated. This machine was used in one of the Royal Dockyards and could be used either as an answering or dictating machine. His telegraphone was a failure; it was not until 1950s that a satisfactory answering machine became available.