"Licence, with the assent of the good men of Port St. Peter in Gerneseye, in view of the fact that the castle of Chirburgh, in that island, wherein in time of war the people used to find refuge, is destroyed and cannot be repaired to the king's advantage, as he is informed, to enclose their town with a good and strong wall, and to crenellate such wall, and to take towards their expenses therein, for 1 year from 1 April next, a custom at the rate of four tournois on every pound of merchandise sold and brought in the island in money of Tours, one half to be paid by the vendor and the other by the buyer."
Granted at Westminster, by King and Council.
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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