Assertion: percussion instrument | /r/MadeOf | metal
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Source sentences:
text: An ancient system of Indian origin, dating from the 4th or 3rd century BC, in the Natya Shastra, a theoretical treatise on music and dramaturgy, by Bharata Muni, divides instruments into four main classification groups: instruments where the sound is produced by vibrating strings (tata vadya, "stretched instruments"); instruments where the sound is produced by vibrating columns of air (susira vadya, "hollow instruments"); percussion instruments made of wood or metal (Ghana vadya, "solid instruments"); and percussion instruments with skin heads, or drums (avanaddha vadya, "covered instruments").