bootless > unavailing single > single, solitary; unaided
107.12
The Geaunt strooke so maynly mercilesse,
2 That could haue ouerthrowne a stony towre,
And were not heauenly grace, that him did blesse,
4 He had beene pouldred all, as thin as flowre:
But he was wary of that deadly stowre,
6 And lightly lept from vnderneath the blow:
Yet so exceeding was the villeins powre,
8 That with the wind it did him ouerthrow,
And all his sences +stound+, that still he lay full low.
9 stound > stoond 1590
1 The giant struck so mainly merciless,
mainly > powerfully, violently
2 That could have overthrown a stony tower,
That > [That he; That the stroke]
3 And, were not heavenly grace that him did bless,
were not > [were it not; had it not been for] him > [the Redcross Knight] bless > guard, protect from evil