Glass harmonica

The modern Glassharmonica is made from quartz in the shape of a long cylinder, heated to 3100'F and blown out into a special shape, which is then cut in half to get two bowls. In the 18th century, 40% lead glass was used, The bowls were worn and tuned with an emery grind wheel. As the depth of a bowl decreases, the pitch becomes higher. Sometimes, the seven colors of the rainbow were used to symbolize the seven diatonic degrees, black figuring the inflected notes. Modern manufacturers use transparent glass - and gold for the brims of the bowls corresponding to the black keys of a keyboard, as Rollig did in the 18th century.

Glassharmonicas belong to the family of idiophone rubbed instruments. The glasses start vibrating according to a relaxation principle : when a finger rubs a bowl, it alternately catches and releases. This creates a series of impulses which set the bowl into vibration. The phenomenon is complex, so the master glass-blower must be very gifted to give the instrument its personality. A number of parameters can play a part, modify the tone, the mode and the harmonic composition of the bowls. Thus, two bowl,.; giving the same note will have different tones according to the materials used, to their shapes, their thicknesses, their dimensions, their hidden defects.

It is said that sounds and noises are closely related to each period of time. It would be interesting to know what has caused the renewal of the glassharmonica at the end of the 20th century and the passion it has aroused - maybe simply the new demands of both music specialists and interpreters in quest for authenticity.

...as Lucia said : "Un' armonia celeste, di', non ascolti?" ("Can't you hear a celestial harmony ?")