Navy Office

Sergison began his career as a dockyard clerk in 1671 and in 1675 was appointed an extra clerk to the Comptroller of Victualling Accounts in the Navy Office. In 1677 he was made Chief Clerk to the Clerk of the Acts in which office he remained until 1686. For two years he was secretary of the new commission for conducting current business and continued with the title of Secretary when the Navy Board was re-constituted in 1688. In the following year he was made Assistant Clerk of the Acts and in 1690 became Clerk of the Acts, a post which he held until 1719.