 By the 18th century the structure was dilapidated, though part of the east range has always remained habitable.James Erskine inherited the Rosslyn and Dysart estates in 1789, from his cousin James Paterson St Clair, upon which he adopted the surname of St Clair-Erskine.In 1805, he inherited the title of Earl of Rosslyn (created 1801 for Alexander Wedderburn); since that date, the Rosslyn estate has been in possession of the Earl of Rosslyn.