of jealousy, she invites Goneril to go with her.  Goneril refuses, but then, seeing Regan’s motive, contemptuously and ironically consents (I doubt if ‘O ho, I know the riddle’ should be ‘aside,’ as in modern editions, following Capell).  Accordingly the two sisters go out, followed by their soldiers; and Edmund and Albany are just going out, in a different direction, to Albany’s tent when Edgar enters.  His words cause Albany to stay; Albany says to Edmund, as Edmund leaves, ’I’ll overtake you’; and then, turning to Edgar, bids him ‘speak.’

6.  V. iii. 151 ff.

When Edmund falls in combat with the disguised Edgar, Albany produces the letter from Goneril to Edmund, which Edgar had found in Oswald’s pocket and had handed over to Albany.  This letter suggested to Edmund the murder of Albany.  The passage in the Globe edition is as follows: 

Gon. This is practice, Gloucester: 
By the law of arms thou wast not bound to answer
An unknown opposite:  thou art not vanquish’d,
But cozen’d and beguiled.

Alb. Shut your mouth, dame,
Or with this paper shall I stop it:  Hold, sir;
Thou worse than any name, read thy own evil: 
No tearing, lady; I perceive you know it.
[Gives the letter to Edmund.

Gon. Say, if I do, the laws are mine, not thine: 
Who can arraign me for’t?

Alb. Most monstrous! oh! 
Know’st thou this paper?

Gon. Ask me not what I know. [Exit.

Alb. Go after her:  she’s desperate:  govern her.

Edm. What you have charged me with, that have I done;
And more, much more; the time will bring it out. 
’Tis past, and so am I. But what art thou
That hast this fortune on me?

The first of the stage-directions is not in the Qq. or Ff.:  it was inserted by Johnson.  The second (’Exit’) is both in the Qq. and in the Ff., but the latter place it after the words ‘arraign me for’t.’  And they give the words ‘Ask me not what I know’ to Edmund, not to Goneril, as in the Qq. (followed by the Globe).

I will not go into the various views of these lines, but will simply say what seems to me most probable.  It does not matter much where precisely Goneril’s ‘exit’ comes; but I believe the Folios are right in giving the words ‘Ask me not what I know’ to Edmund.  It has been pointed out by Knight that the question ‘Know’st thou this paper?’ cannot very well be addressed to Goneril, for Albany has already said to her, ’I perceive you know it.’  It is possible to get over this difficulty by saying that Albany wants her confession:  but there is another fact which seems to have passed unnoticed.  When Albany is undoubtedly speaking to his wife, he uses the plural pronoun, ‘Shut your mouth, dame,’ ’No tearing, lady; I perceive you know it.’  When then he asks ’Know’st thou this paper?’ he is probably not speaking to her.