At the administrative heart of pre-Revestment Mann. John Quayle held the post of Clerk of the Rolls — the Duke's principal administrative officer — and was simultaneously Comptroller of Customs at Castletown. Bridge House, standing on the harbour, served as both the lordship's administrative centre and the family counting house. His daughter married into the Taubman family. His son George Quayle — born of the marriage between John Quayle and Margaret 'Peggy' Moore — became a banker, politician, and Speaker of the Keys. George ran Quayle's Bank from Bridge House and in 1789 built the armed yacht Peggy in a concealed dock beneath the building, with sea gates, secret passages, and mechanical alarm bells. The Peggy was discovered in 1935 — the oldest surviving yacht in the world. John Quayle's testimony to the 1792 Commissioners provided the most detailed surviving account of the pre-Revestment administration. His verdict on the Revestment: 'All the old landmarks are taken away or destroyed, and no new ones substituted in their room.'