Sentence:  With keener stare / The man's eyes scanned him, with the flare / Of yellow light full on his face, / As though his memory sought to trace / Something familiar in the lean / Clearcut young features and the clean / Blue <WSD>winkers</WSD>: then his own hard eyes / Twinkled ... 
Meaning of the word marked with <WSD> tags:  An eye.<ref>Anonymous, "Real Life in London", London: T. Johnson, no date (19th century), Volume 1, p.(nbsp)608, footnote: “"Wakeful winker"—A sharp eye.”[https://archive.org/details/reallifeinlondon01londiala]</ref>