Simple pipes produce signals – to direct the herding dogs or to warn other shepherds of danger. A flute is needed to play melodies. It does not even have to be particularly elaborate in design. The art lies in skilful blowing technique and the correct opening and closing of the tone holes. It is not known whether shepherds were always good musicians. Nor is it known what songs they played. However, musical archaeology is endeavouring, through ongoing experiments, to determine the possible tone sequences of each instrument and the melodies that can be produced with them.