In Virgil's Aeneid, Book IX, John Dryden (1631-1700) uses "sound the flute" to announce the call to an epic battle. Dryden writes, "Eunuchs in the Mother's rites / (Where with unequal sound the flute invites)."
    According to the Oxford English Dictionary, second edition, a flute is a musical wind instrument, consisting of a hollow cylinder or pipe, with holes along its length, stopped by the fingers, or by keys which are opened by the fingers. The flute of the ancients, whether single or double, was blown through a mouthpiece at the end. About the middle of the 18th century, this was entirely superseded by the transverse or German flute, which is blown through an orifice at the side near the upper end.
    In architecture, a flute is a channel or furrow in a pillar, resembling the half of a flute split longitudinally, with the concave side outwards.

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