Sentence:  ... an older man, attired in gray, with hair to match, was busily engaged at one end of the room packing a quantity of small cases into a larger one, and continuing to hold converse with himself by means of the monosyllable “yes,” differently <WSD>intonated</WSD>, at intervals of half-a-minute, “y-e-s—y-e-s.” 
Meaning of the word marked with <WSD> tags:  To say or speak with a certain intonation.