[248.] his = its: see [note], l. 96. The pronoun refers to ‘something holy.’
[251.] smoothing the raven down. As the nightingale’s song smooths the rugged brow of Night (Il Pens. 58), so here the song of the lady smooths the raven plumage of darkness. In classical mythology Night is a winged goddess.
[252.] it, i.e. darkness.
[253.] Circe ... Sirens three. In the Odyssey the Sirens are two in number and have no connection with Circe. They lived on a rocky island off the coast of Sicily and near the rock of Scylla (l. [257]), and lured sailors to destruction by the charm of their song. Circe was also a sweet singer and had the power of enchanting men; hence the combined allusion: see also Horace’s Epist. i. 2, 23, Sirenum voces, et Circes pocula nôsti. Besides, the Sirens were daughters of the river-god Achelous, and Circe had Naiads or fountain-nymphs among her maids.
[254.] flowery-kirtled Naiades: fresh-water nymphs dressed in flowers, or having their skirts decorated with flowers. A kirtle is a gown; Skeat suggests that it is a diminutive of skirt.
[255.] baleful, injurious (A.S. balu, evil).
[256.] sung. “The verbs swim, begin, run, drink, shrink, sink, ring, sing, spring, have for their proper past tenses swam, began, ran, etc., preserving the original a; but in older writers (sixteenth and seventeenth centuries) and in colloquial English we find forms with u, which have come from the passive participles.” (Morris). take the prisoned soul, i.e. would take the soul prisoner; ‘prisoned’ being used proleptically.
[257.] lap it in Elysium. Lap is a form of wrap: comp. L’Alleg. 136, “Lap me in soft Lydian airs.” Elysium: the abode of the spirits of the blessed; comp. L’Alleg. 147, “heaped Elysian flowers.” Scylla ... Charybdis. The former, a rival of Circe in the affections of the sea-god Glaucus, was changed into a monster, surrounded by barking dogs. She threw herself into the sea and became a rock, the noise of the surrounding waves (”multis circum latrantibus undis,” Aen. vii. 588) resembling the barking of dogs. The latter was a daughter of Poseidon, and was hurled by Zeus into the sea, where she became a whirlpool.
[260.] slumber: comp. Pericles, v. 1. 335, “thick slumber Hangs upon mine eyes.”
[261.] madness, ecstasy. The same idea is expressed in Il Pens. 164: “As may with sweetness, through mine ear, Dissolve me into ecstasies, And bring all heaven before mine eyes.” In Shakespeare ‘ecstasy’ occurs in the sense of madness; see Hamlet, iii. 1. 167, “That unmatched form and feature of blown youth, Blasted with ecstasy”; Temp. iii. 3. 108, “hinder them from what this ecstasy May now provoke them to”: comp. also “the pleasure of that madness,” Wint. Tale, v. 3. 73. See also l. [625].