What is (a) The plectrum with which musicians strike the strings of certain instruments. (b) The tube of a musical instrument. He touched the tender stops of various quills. Milton called?

quill — (Mus.) (a) The plectrum with which musicians strike the strings of certain instruments. (b) The tube of a musical instrument. He touched the tender stops of various quills. Milton. (Webster's 1913.)

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