Green’s Dictionary of Slang

1. a monocle .

1825		S. Woodworth Forest Rose II ii: See! he is honoring us with a squint through his quizzer.
1881		Exter & Plymouth Gaz. 10 May 3/4: His lordship put his quizzer up in his right eye.
1902		St James’s Gaz. 11 Feb. 17/2: The Etyeglass brigade [...] Nobpdy will contend that a ‘quizzer’ lends distinction to a face.
1929		(ref. to 1817) Yorks Post 10 Sept. 3/4: This old firm dates from 1817, when John Lenton started manufacturing real horn magnifiers and quizzers.

2. (US) in pl., spectacles.

1879		A. Pinkerton Reminiscences 269: Superintendent Warner [...] adjusted his quizzers, and began listening.
1894		Record-Union (Scaramento, CA) 22 Sept. 6/1: Bob White [...] is wearing double concave quizzers over his bulbous eyes.