Sentence:  Long after his cigar burnt bitter, he sat with eyes fixed on the blaze. When the flames at last began to <WSD>flicker</WSD> and subside, his lids fluttered, then drooped; but he had lost all reckoning of time when he opened them again to find Miss Erroll in furs and ball-gown kneeling on the hearth and heaping kindling on the coals,nb.... 
Meaning of the word marked with <WSD> tags:  To burn or shine unsteadily, or with a wavering light.