Hekiganroku - Case 72: Ungan's "Can You?"

Hyakujo said to Ungan,
  "How does one speak with one's lips and throat closed?" [1]
Ungan said,
  "Can you, Master, do such a thing?"
Hyakujo said,
  "Now I will lose my Dharma descendants." 

[1]: cf cases 70 and 71