Some rooms in the main portion of the museum were wallpapered at the turn of the 20th century. Wallpaper was stripped as time went on, but a remnant of the wallpaper in the Long Room remains above the mantle. It is a Federal-period patterned paper. Federal-style architecture and décor was most popular between the years 1780 and 1830, however, the exact dating of the wallpaper is unknown. Smaller pieces of wallpaper were discovered between the wall and the mantle, but were unfortunately too small to show any other patterns. In 1935, photos of the museum were taken for the Historic American Building Survey, clearly showing the wallpaper in the Long Room.