What is 4. To slip, or to become slightly displaced; as, the collodion on a negative, or a coat of varnish, may creep in drying; the quicksilver on a mirror may creep called?

creep — 4. To slip, or to become slightly displaced; as, the collodion on a negative, or a coat of varnish, may creep in drying; the quicksilver on a mirror may creep. (Webster's 1913.)

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