“Whereat I seized him by the neck upon the nape and said: ‘Thou shalt declare thy name or of the locks on this be left with none’.”
. . . . .
Whereas earlier, Dante searched for rhymes that would help alleviate the suffering of the shades in the upper circles, now he calls out for "rhymes rugged and harsh and hoarse/ fit for the hideous hole" [Sayers' translation] — horrible words befitting the utter horror of this most horrendous place, the very bottom of Hell, reserved for the most heinous sinners. Dante again invokes the Muses to help him write what he sees, just as he had done at the beginning of his journey. This time the invocation is longer and even more passionate. He knows that this portion of the journey is going to be harsh and horrible, and he hopes that he has the words for it. The geography of the final pit of Hell is explained in these two cantos. There are four rounds in this circle of traitors. The first, Caina, reserved for those who were traitors to their kin, is named for the Biblical Cain who slew his brother, Abel. Remember also that Francesca (Canto V), in her story, says that Caina awaits hers and Paolo's murderer, Paolo's brother. The sinners that Dante finds here are two brothers who killed one another in a squabble over their inheritance, hence they must spend all of eternity locked together, bickering and butting heads.