The Holinshed Texts (1587, Volume 6, p. 55)

Compare 1577 edition: 1 This castell being thus woone, earle Robert sub|dued also such as kept the Ile of Portland,The Ile of Portland. Circester. and had fensed it after the maner of a fortresse: afterwards he came to Circester, and there assembled all those that fauoured the part of the empresse, meaning with all conuenient spéed to go to Oxford, & there to giue battell to king Stephan, if he would abide it. Who after his deliuerance from captiuitie, had assembled a great host of men,The empresse besieged in Oxford. and comming to Oxford, where the empresse then laie, suddenlie besieged hir, before she looked for him. And to the end also that he might compell the townsmen to yeeld, or else kéepe them from entring which would come to their succors, he ranged abroad into the countrie with part of his ar|mie, wasting all afore him by fire & sword. This siege continued almost two moneths, in maner from his deliuerie in the beginning of Nouember, vntill Christmasse immediatlie following: in somuch that through lacke of vittels they within the towne be|gan to raise mutinies. The empresse therefore doub|ting the sequele, and séeing hir prouision to decaie, deuised a shift how to escape that present danger, which by force she was vnlikelie to performe.

Compare 1577 edition: 1 It was a verie hard winter that yeare, the Thames and other riuers thereabouts were frosen, so that both man and horsse might safelie passe ouer vpon the yce,

N. Triuet. Simon Dun. Wil. Paru. Ran. Higd. Matth. Paris.

The empresse escapeth out of Oxford.

Polydor. Wil. Malm. Simon Dun. Matth. Paris.

Brian sonne to the earle of Glocester.

the fields were also couered with a thicke and déepe snow. Herevpon taking occasion, she clad hir selfe and all hir companie in white appa|rell, that a far off they might not be discerned from the snow; and so by negligence of the watch that kept ward but slenderlie, by reason of the excéeding cold weather, she and hir partakers secretlie in the night issued out of the towne, and passing ouer the Thames, came to Walingford, where she was recei|ued into the castell by those that had the same in kée|ping to hir vse: of whom Brian the sonne to the erle of Glocester was the chiefe.

¶ Here we may see the subtiltie of the empresse, whereby she obteined frée and safe passage out of hir enimies hands, who otherwise had taken hir in their net. So that it will be true, that hath neuer béene false, Aeneas Syluius. which Aeneas Syluius (and before him many more driuing vpon the like argument) dooth saie in this distichon:

Non audet stygius Pluto tentare, quod audent

Effraenis monachus plenáque fraudis illa,