Chiang Kan quietly got up and by the light of a candle furtively looked through the letters on Chou Yu's desk.He saw a sealed envelope addressed:"From Ts'ai Mao and Chang Yun."Chiang Kan opened it and read it.It was from Ts'ao Ts'ao's generals,Ts'ai Mao and Chang Yun,and stated their intention to kill Ts'ao Ts'ao and surrender to Wu Kingdom with Ts'ao Ts'ao's head.