What is that with which anything is compared for proof of its genuineness; a touchstone; a standard. Life, force, and beauty must to all impart, At once the source, and end, and test of art. Pope called?

test — That with which anything is compared for proof of its genuineness; a touchstone; a standard. Life, force, and beauty must to all impart, At once the source, and end, and test of art. Pope. (Webster's 1913.)

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