"quandam cameram suam infra manerium suum de quod supra costeram maris situatur"
Granted at Westminster, by King.
Licensed in 1351 and 1352. This licence, for a 'chamber (cameram) in his manor probably refers to his newly built tower.
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;
Sir Marmaduke [i] Constable (d. 1378), presumably William [ii]'s younger brother, was lord of Flamborough. By 1351 Marmaduke had the resources to undertake rebuilding at Flamborough and obtained licence to crenellate the manor. Alongside this suggestion of growing prosperity Marmaduke was taking on a larger public role. In 1349 he was appointed an executor of Archbishop Zouche, he was added to the commission of the peace in 1351, and was sheriff of Yorkshire in 1360 62 and 1366 7. He was discharged as commissioner in May 1370, which seems to mark the end of his public career, although he did not die until 21 May 1378. (Horrox)
Biographical source include;
More details about licences to crenellate can be found here.
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