A friend posted this on Facebook the other day and I was very impressed, Certainly I've never heard anything like it before. So I'm sharing it here with you.
Apparently no one knows for sure where the portative organ began. The air is supplied by a bellows at the rear of the instrument which the musician squeezes. Organs of various kinds were known in the Roman empire and spread across Europe during the medieval era, although the adoption of the pipe organ as a chuch instrument was comparatively recent. This music is by the 14th century Italian composer, Gheradello da Firenze: