This color-enchanced photo of the center of the ceiling shows the various material types used. Yellow indicates original 18th-century plaster containing hide glue and lime (also known as "brown" plaster). Green indicates original 18th-century plaster containing brick dust and lime (also known as "pink" plaster). Blue indicates 19th-century gypsum-based plaster (also known as "white" plaster). This image clearly shows repairs to the ceiling (blue areas) made by William Key Howard, Jr.