518. ~rifted rocks~: rifted = riven. Orpheus, in search of Eurydice, entered the lower world through the rocky jaws of Taenarus, a cape in the south of Greece (see Virgil _Georg._ iv. 467, _Taenarias fauces_); here also Hercules emerged from Hell with the captive Cerberus.
519. ~such there be~. See note on l. 12 for this indicative use of _be_.
520. ~navel~, centre, inmost recess. Shakespeare (_Cor._ iii. l. 123) speaks of the 'navel of the state'; and in Greek Calypso's island was 'the navel of the sea,' while Apollo's temple at Delphi was 'the navel of the earth.'
521. ~Immured~, enclosed. Here used generally: radically it = shut up within walls (Lat. _murus_, a wall).
526. ~murmurs~. The incantations or spells of evil powers were sung or murmured over the doomed object; sometimes they were muttered (as here) over the enchanted food or drink prepared for the victim. Comp. l. 817 and _Arc._ 60, "With puissant words and _murmurs_ made to bless."
529. ~unmoulding reason's mintage charactered~, _i.e._ defacing those signs of a rational soul that are stamped on the human face. The figure is taken from the process of melting down coins in order to restamp them. 'Charactered': here used in its primary sense (Gk. +charaktêr+, an engraven or stamped mark), as in the phrase 'printed characters.' The word is here accented on the second syllable; in modern English on the first.
531. ~crofts that brow~ = crofts that overhang. Croft = a small field, generally adjoining a house. Brow = overhang: comp. _L'Alleg._ 8, "low-browed rocks."
532. ~bottom glade~: the glade below. The word _bottom_, however, is frequent in Shakespeare in the sense of 'valley'; hence 'bottom glade' might be interpreted 'glade in the valley.'
533. ~monstrous rout~; see note on the stage-direction after l. 92. Comp. 'the bottom of the monstrous world,' _Lyc._ 158. In _Aen._ vii. 15, we read that when Aeneas sailed past Circe's island he heard "the growling noise of lions in wrath, ... and shapes of huge wolves fiercely howling."
534. ~stabled wolves~, wolves in their dens. _Stable_ (= a standing-place) is used by Milton in the general sense of abode, _e.g._ in _Par. Lost_, xi. 752, "sea-monsters whelped and _stabled_." Comp. "Stable for camels," _Ezek._ xxv. 5, and the Latin _stabulum_, _Aen._ vi. 179, _stabula alta ferarum_.