In the 1960s in the UK ethnomusicologist John Taylor developed a new fingering system with a four-hole ocarina that was able to produce an entire chromatic scale.
Since then the four-hole version of the ocarina has become the most widely taught musical instrument in the United Kingdom.
More information about his work at
http://bit.ly/johntaylorocarina#7ocarinaPlayers #OcarinaHistory #Ocarina #OcarinaFestival