It is nothing.

DUCHESS

Nay, it is from some girl.

GUIDO

You know 'tis not.

DUCHESS

[turns her back and opens it]
Now, traitor, tell me what does this sign mean,
A dagger with two leopards wrought in steel?

GUIDO

[taking it from her] O God!

DUCHESS

I'll from the window look, and try
If I can't see the porter's livery
Who left it at the gate! I will not rest
Till I have learned your secret.
[Runs laughing into the corridor.]

GUIDO