Assertion: violin's sound | /r/CreatedBy | vibrating columns of air
Facets:
Source sentences:
text: An ancient Hindu system named the Natya Shastra, written by the sage Bharata Muni and dating from between 200 BC and 200 AD, divides instruments into four main classification groups: instruments where the sound is produced by vibrating strings; percussion instruments with skin heads; instruments where the sound is produced by vibrating columns of air; and "solid", or non-skin, percussion instruments.