he knew the building was a 13th century friary , and the bare parts of the walls and the ceiling were testimony to this , yet all of the furniture - the bed , dresser , draperies and paintings , and even a real-life x-frame chair derived from the sella curulis ( folding throne ) , which hed only previously seen on a portrait by william larkin that was hung in his own house - were from the 15th to 19th centuries .