Sentence:  At this moment he saw the plate <WSD>cottoning</WSD>, as he expressed it, to his young friend, Charles Freeland, who sat in the pew at his right. He watched to see what the young merchant would give ; and to his amazement, he saw the young man put in a fifty dollar note! 
Meaning of the word marked with <WSD> tags:  To develop a porous, cottony texture.