Note 85 — SCENE II.
Reading edition
"Impartial" is occasionally used by old writers in the sense of "unkindly." Cf. Prologue to Peele's Arraignment of Paris:—
"Th' unpartial daughters of Necessity Bin aiders in her suit."
So in William Smith's Chloris(Sonnet 11):—
"No, it was not Nature's ornament But wingèd love's unpartial cruel wound."