Sentence:  In the morning, one might say, his face was of a fine florid hue, but after twelve o'clock, meridian -- his dinner hour -- it blazed like a grate full of Christmas coals; and continued blazing -- but, as it were, with a gradual <WSD>wane</WSD> -- till six o'clock, PM, or thereabouts; after which, I saw no more of the proprietor of the face, [...]. 
Meaning of the word marked with <WSD> tags:  A gradual diminution in power, value, intensity etc.