—Act III, scene iv, lines 70-72
The aged sibyl is an image used often by Shakespeare (see page I-452), and we may well believe that Othello accepts the truth of sibyls as he does of Pliny's wonders.
Still Desdemona can't produce the handkerchief and still she fearfully denies it is lost. Othello stalks off in a rage.
Iago now sets about supplying the last touch. He has planted the handkerchief in Cassio's chambers. Cassio finds it, likes it, and gives it to his mistress, Bianca (a courtesan), to copy over so that he will have a similar handkerchief after he returns this one to its rightful owner, whoever that might be.
Iago then finds occasion to draw Cassio aside, with Othello watching from a place where he can see but not hear. Iago teases Cassio with the great love Bianca has for him. Cassio preens and smirks with the usual male self-satisfaction over such matters and Othello can only assume (in his fevered state) that he is laughing over his amour with Desdemona.
And then Bianca enters and throws the handkerchief back at Cassio, for she has decided it must belong to another one of his girlfriends. Of course, Othello recognizes it at once and the case is proven for him. The handkerchief he gave to Desdemona, she gave to Cassio, who thinks so little of it he passes it on to a courtesan. Othello is ready to kill Desdemona.
But the outside world intervenes. A deputation of important Venetian officials has arrived under the leadership of one Ludovico. They bring a message recalling Othello to Venice now that the war danger is gone and appointing Cassio as his successor.
Othello greets them with the necessary ceremony but is so far gone in his jealous madness that he cannot put a good face on matters even for the sake of the Venetian deputation. When Desdemona innocently tries to speak in Cassio's favor to the Venetians, Othello strikes her.
The horrified Ludovico upbraids Othello and exclaims at the sight of the weeping Desdemona. But the raving Othello says:
—Act IV, scene i, lines 244-46
In other words, if tears falling to earth could act as semen to make the earth pregnant and bring forth life, Desdemona's tears would cause it to bring forth crocodiles.
This refers to a well-known legend concerning crocodiles. (Othello is a veritable compendium of legends.) Crocodiles were supposed to moan and sigh, so that passers-by might think human beings in distress were somewhere nearby. If any were softhearted enough, or curious enough, to turn aside in search of them, the crocodile's jaws snapped shut, and it would then continue to weep even while eating.
The story is quite untrue, but the phrase "crocodile tears" has entered the language to represent any form of hypocritical grief. The implication is that Desdemona's modesty and virtue are tissues of hypocrisy. The irony, of course, is that the play is filled with crocodile tears; they are all Iago's and Othello doesn't see them.
When Othello stalks off, Ludovico wonders if he is sane, and Iago seizes the opportunity to encourage that thought of possible insanity without actually committing himself to it.
But by now Iago has almost more strings in his hand than he can properly handle. Thus, when Othello takes himself to Desdemona's chamber to give her a bitter tongue-lashing, Emilia openly wonders if Othello might not be the victim of malicious slander. Then too, Roderigo has been gulled and robbed by Iago to the point where he can take no more. He threatens to talk to Desdemona directly and request the return of his jewels.
We can be pretty sure that Desdemona has never received any jewels but that Iago, as go-between, has kept them. Iago, therefore, must begin to shut mouths.
He begins by promising Roderigo that he will have Desdemona the very next night if he can manage to keep Othello on the island that long. Iago explains that Othello has been recalled and ordered to a distant country (another lie). This is to force Roderigo to act, for it will seem to him that Desdemona is about to move utterly beyond his grasp. Iago says:
—Act IV, scene ii, lines 224-26
Mauritania was the name given in ancient times to the northwest shoulder of Africa, the region now called Morocco. It may be used here as a vague term, meaning "land of the Moors," that is, north Africa generally.
Iago arranges to have Roderigo attempt to find occasion to kill Cassio, since the death of Othello's appointed successor would force the Moor to remain on the island for a while. (From Iago's standpoint, this will get rid of the hated Cassio, and Othello has ordered him to do that; and he will find occasion, we can well imagine, to take care of Roderigo too.)
Matters now rush to their horrible climax. It is night and Desdemona, in almost unbearable depression, goes to bed.
Cassio, returning from time spent with his ladylove, is set upon by Roderigo. They fight and both are wounded. Men come running, and Iago, finding that Cassio is not dead, makes the best of matters by killing Roderigo and shutting his mouth at least.
While that is going on, Othello is trying to do his part. He comes upon Desdemona sleeping and even now finds he still hesitates. He looks from the candle he carries to the sleeping woman and says:
—Act V, scene ii, lines 8-13
Prometheus, in the Greek myths, had first made man the gift of fire, stealing it from the sun (see page I-437). A later myth also made him the creator of man. He was supposed to have made clay models into which he breathed life.
Othello's reference to "Promethean heat" is therefore a double-barreled allusion. It refers to Prometheus' connection with the sun's fire; not just ordinary fire but a special kind. Secondly, it refers to Prometheus' ability to infuse cold and lifeless clay with the warmth of a living human body; and that ability Othello lacks.
Othello no longer raves. He goes about the task of killing with a cold sorrow. Desdemona wakes and Othello accuses her of having given the handkerchief to Cassio. He will not accept her denial but tells her Cassio is dead (he assumes Iago has done his work properly), and Desdemona's terror at that news seems to him to be the final admission.
He strangles her with her pillow and even while he is forcing his weight down on her fragile neck, there is a clamor at the door. Emilia demands entrance. Othello closes the bed curtains and lets her in. Emilia has come to tell of the deadly fight between Roderigo and Cassio.
Othello says calmly:
—Act V, scene ii, lines 108-10
It has always been tempting to think that changes in the heavens bring about analogous changes on the earth (something that is the basis of the pseudo science of astrology). The regular changes of the moon from new to full and back again would seem to imply that certain passions or foibles of men would wax and wane in sympathy.