Designed in 1878 by architect John Hubbard Sturgis, the Church of the Advent is a prominent example of the English gothic revival style. Blackburn was asked to clean and conserve the delicately carved woodwork and polychrome sculpture of the Lady Chapel completed by the renowned master wood carver Johannes Kirchmayer. Over the years, the woodwork had become dark and discolored due to exposure to dust and heating system soot. The many pierced carvings had collected dirt and debris, which had become permanently bonded to the wood finish. In addition, edges and corners of the wood furniture had been abraded by a century of human use. The challenge for Blackburn was to carefully clean the surfaces without damaging the original finishes and polychrome colors used on the sculpture. To accomplish this, a dilute solution of a non-ionic detergent was applied and dried with lint free cloth. After cleaning the wood surfaces, some high traffic areas required touching up with brown pigmented stain and a coat of brown wax.