[603.] grisly legions. ‘Grisly,’ radically the same as grue-some = horrible, causing terror. In Par. Lost, iv. 821, Satan is called “the grisly king.” ‘Legions’ is here a trisyllable.
[604.] sooty flag of Acheron. Acheron, at first the name of a river of the lower world, came to be used as a name for the whole of the lower world generally. Todd quotes from P. Fletcher’s Locusts (1627): “All hell run out and sooty flags display.”
[605.] Harpies and Hydras. The Harpies (lit. ‘spoilers’) were unclean monsters, being birds with the heads of maidens, with long claws and gaunt faces. Hydras, here used as a general name for monstrous water-serpents (Gk. hydōr, water); the name was first given to the nine-headed monster slain by Hercules. See Son. xv. 7, “new rebellions raise Their Hydra heads”; the epithet ‘hydra-headed’ being applied to a rebellion, an epidemic, or other evil that seems to gain strength from every endeavour to repress it.
[607.] return his purchase back, i.e. ‘give up his spoil,’ or (as in the MS.) ‘release his new-got prey.’ To purchase (Fr. pour-chasser) originally meant to pursue eagerly, hence to acquire by fair means or foul: it thus came to mean ‘to steal’ (as frequently in Spenser, Jonson, and Shakespeare), and ‘to buy’ (its current sense). See Trench, Study of Words; Hen. V. iii. 2. 45, “They will steal anything, and call it purchase”; i. Hen. IV. ii. l. 101, “thou shalt have share in our purchase.”
[609.] venturous, ready to venture. See [note], l. 79.
[610.] yet, nevertheless. The meaning is: ‘Though thy courage is useless, yet I love it.’ emprise: an obsolete form (common in Spenser) of enterprise. It is literally that which is undertaken; hence ‘readiness to undertake’; hence ‘daring.’
[611.] can do thee little stead, i.e. can help thee little. Stead, both as noun and verb, is obsolete except in certain phrases, e.g. ‘to stand in good stead,’ and in composition, e.g. steadfast, homestead, instead, Hampstead, etc. Its strict sense is place or position: comp. Il Pens. 3, “How little you bested.”
[612.] Far other arms, i.e. very different arms. ‘Other’ has here its radical sense of ‘different,’ and can therefore be modified by an adverb.
[615.] unthread, loosen. Comp. Temp. iv. l. 259, “Go charge my goblins that they grind their joints With dry convulsions, shorten up their sinews With aged cramps.”
[617.] As to make this relation, i.e. as to be able to tell this.