The clauses relating to Geoffrey's castles are deserving of special attention on account of the important part which the castle played in this great struggle. The erection of unlicensed ("adulterine") castles and their rapid multiplication throughout the land is one of the most notorious features of the strife, and one for which Stephen's weakness has been always held responsible. It is evident, however, from these charters that the Crown struggled hard against the abdication of its right to control the building of castles, and that even when reduced to sore straits, both Stephen and the Empress made this privilege the subject of special and limited grant. By this charter the earl secures the license of the Empress for a new castle which he had erected on the Lea. He may have built it to secure for himself the passage of the river, it being for him a vital necessity to maintain communication between the Tower of London and his ancestral stronghold in Essex. But the remainder of the passage involves a doubt. The Empress professes to repeat the permission in her former charter that he may construct one permanent castle, in addition to those he has already, anywhere within his fief. Yet a careful comparison of this permission with that contained in her former charter, and that which was granted by Stephen, in his charter between the two, proves that she was really confirming what he, not she, had granted. MAUD (1141). "Et præterea concedo illi ut castella sua que habet stent ei et remaneant ad inforciandum ad voluntatem suam." STEPHEN. "Et præterea firmiter ei concessi ut possit firmare quoddam castellum ubicunque voluerit in terra sua, et quod stare possit." MAUD (1142). "Concedo etiam ei quod firmet unum castellum ubicunque voluerit in terra sua, _sicut ei per aliam cartam meam concessi_, et quod stet et remaneat." As we can trace, in every other instance, the relation of the various charters without difficulty or question, it would seem that we have here to do with an error, whether or not intentional. We then come to the clauses in favour of Geoffrey's relatives and friends. This is a novel feature which we cannot afford to overlook. It is directly connected with the question of that important De Vere charter to which we shall shortly come.