"Licence for Thomas, bishop of Bath and Wells, and his successors to execute all things specified in letters patent dated 29 March, 14 Edward III, in favour of Ralph, then bishop of Bath and Wells hitherto not executed, and to enclose the churchyard of the cathedral church of Wells arid the precinct of the houses of them and the canons of the church in the city of Wells with a stone, wall and to crenellate the same and make towers there for the greater security of the bishop and canons; so that the gate and posterns whereof mention is made in the said letters be shut and opened at the due times, as shall seem good to Thomas and his successors or to the dean and canons resident there, for surety of the peace and quiet of them and of the other ministers of the church; and mandate to the bailiffs and other officers and the citizens and ministers of the city to be intendant to the bishop and his successors herein and to commit to prison till further order any rebellious herein."
Granted at Westminster, by privy seal etc.
Licensed in 1207, 1286, 1340 and 1451. The 1340 licence had produced the bishops palace, this licence resulted in the Penniless Porch and the other walls and gates of the close.
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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