"Grant, of special grace, to John Wolf, king's esquire, and his heirs, of free warren in all their lands belonging to their manor of Kentysbery, co. Devon; grant also to the said John of licence to enclose his said manor with a wall of stones and mortar and to build a tower or towers there and to embattle, crenellate and machicolate the said wall and towers, and so to hold them to him and his heirs."
Granted at Reading, by King and of the said date etc. {by authority of parliament}.
Original source is
(In fact, the original source given is usually a transcription/translation of what are precious medieval documents not readily availably. It should be noted that these transcription/translations often date to the nineteenth or early twentieth centuries and that unwitting bias of transcribers may affect the translation. Care should also be taken to avoid giving modern meaning to the medieval use of certain stock words and terms.)
Significant later source are;
More details about licences to crenellate can be found here.
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