[615] See his charter to Wallingford (printed in Hearne's _Liber Niger_ (1771), pp. 817, 818), in which he grants privileges "pro servitio et labore magno quem pro me sustinuerunt in acquisitione hereditarii juris mei in Anglia." CHAPTER IX. FALL AND DEATH OF GEOFFREY. The movements of Geoffrey during the latter half of 1142 are shrouded in utter darkness. After the surrender of the isle of Ely, we lose sight of him altogether, save in the glimpse afforded us by the Oxford intrigue. It is, however, quite possible that we should assign to the period of the siege of Oxford Castle (September-December, 1142) a charter to Abingdon Abbey which passed at Oxford.[616] For if we deduct from its eight witnesses the two local barons (Walter de Bocland and Hugh de Bolbec), five of the remaining six are found in the Canterbury charter.[617] In that case, Geoffrey, who figures at their head, must have been at Oxford, in Stephen's quarters, at some time in the course of the siege. He would obviously not declare for the Empress till the time was ripe for the scheme, and, in the meanwhile, it might disarm suspicion, and secure his safety in the case of the capture or defeat of the Empress, if he continued outwardly in full allegiance to the king. It was not till the following year that the crisis at length came. Stephen, at Mid-Lent, had attended a council at London, at which decrees were passed against the general disregard of the rights and privileges of the Church. Her ministers were henceforth to be free from outrage, and her sanctuaries from violation, under penalty of an excommunication which only the pope himself could remove.[618]