The harmonica is the world’s best-selling musical instrument. Harmonicas originated in the early 1800s in Europe. They gained popularity in the 1920s in the U.S. and were used in blues recordings. By 1986 the harmonica maker Hohner produced 1 billion harmonicas.
Optus, the second largest telecommunications company in Australia, has a long association with nature so M&C Saatchi, Sydney set about exploring communication between humans...