The passage, therefore, should be printed thus: 

Laer. Have at you now!

[Laertes wounds Hamlet; then, in scuffling,
they change rapiers.

King. Part them; they are incensed.

Ham. Nay, come, again.

[They play, and Hamlet wounds Laertes.  The Queen falls.

FOOTNOTES: 

[Footnote 264:  So Rowe.  The direction in Q1 is negligible, the text being different.  Q2 etc. have nothing, Ff. simply ’In scuffling they change rapiers.’]

[Footnote 265:  Capell.  The Quartos and Folios have no directions.]

NOTE I.

THE DURATION OF THE ACTION IN OTHELLO.

The quite unusual difficulties regarding this subject have led to much discussion, a synopsis of which may be found in Furness’s Variorum edition, pp. 358-72.  Without detailing the facts I will briefly set out the main difficulty, which is that, according to one set of indications (which I will call A), Desdemona was murdered within a day or two of her arrival in Cyprus, while, according to another set (which I will call B), some time elapsed between her arrival and the catastrophe.  Let us take A first, and run through the play.

(A) Act I. opens on the night of Othello’s marriage.  On that night he is despatched to Cyprus, leaving Desdemona to follow him.

In Act II.  Sc. i., there arrive at Cyprus, first, in one ship, Cassio; then, in another, Desdemona, Iago, and Emilia; then, in another, Othello (Othello, Cassio, and Desdemona being in three different ships, it does not matter, for our purpose, how long the voyage lasted).  On the night following these arrivals in Cyprus the marriage is consummated (II. iii. 9), Cassio is cashiered, and, on Iago’s advice, he resolves to ask Desdemona’s intercession ‘betimes in the morning’ (II. iii. 335).

In Act III.  Sc. iii. (the Temptation scene), he does so:  Desdemona does intercede:  Iago begins to poison Othello’s mind:  the handkerchief is lost, found by Emilia, and given to Iago:  he determines to leave it in Cassio’s room, and, renewing his attack on Othello, asserts that he has seen the handkerchief in Cassio’s hand:  Othello bids him kill Cassio within three days, and resolves to kill Desdemona himself.  All this occurs in one unbroken scene, and evidently on the day after the arrival in Cyprus (see III. i. 33).

In the scene (iv.) following the Temptation scene Desdemona sends to bid Cassio come, as she has interceded for him:  Othello enters, tests her about the handkerchief, and departs in anger:  Cassio, arriving, is told of the change in Othello, and, being left solus, is accosted by Bianca, whom he requests to copy the work on the handkerchief which he has just found in his room (ll. 188 f.).  All this is naturally taken to happen in the later part of the day on which the events of III. i.-iii. took place, i.e. the day after the arrival in Cyprus:  but I shall return to this point.