I believe the correct answer is: "Of stagnant waters: altar, sword, and pen,
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Metonymy is the type of metaphor, figure of speech, which is uses the substitution of the name of an attribute or adjunct for that of the thing meant. In the poem “London” written by William Wordsworth in 1802, the line which uses metonymy to refer to art and literature is the third line: “Of stagnant waters: altar, sword, and pen,” as the pen represents the whole literature in England after Milton’s death.
