Preparation Lab History Field Museum exclusive archive pictures on the trail of fossil preparation labs. 1899 CSGEO3248.jpg © The Field Museum, CSGEO3248, Photographer Charles Carpenter. Elmer Riggs, the first curator of Fossil Mammals (wearing cap) and field laboratory assistant Harold W. Menke preparing Grand Junction Colorado fossils including the Brachiosaur femur still in plaster jacket at left. Paleontology Laboratory, Field Columbian Museum. Geology specimen P25107. 1924 CSGEO49133.jpg © The Field Museum, CSGEO49133. Geology Preparator John B. Abbott assembles bones of (South American Argentina) dinosaurs Argyrosaurus and Antarctosaurus femur in Geology Prep Lab. When found in Argentina in 1924, the femur was in four fragments. They were then glued together with plaster of Paris. The chain hoist is being used to position one part of the femur on top of the other part. 1993 GEO85683_8.jpg © The Field Museum, GEO85683_8, Photographer John Weinstein. This is one of two fossil prep labs on the third floor in the Geology Department after renovation. This picture was taken upon completing the renovation of the lab. The lab has not changed much since then. 1998 GN88689_23ac.jpg © The Field Museum, GN88689_23Ac, Photographer John Weinstein. A public viewing lab setup in the Stanley Field Hall with visitors looking over fossil preparators at work. 2011 McDonald's_lab_2011_4.jpg © The Field Museum, Photographer: Constance Van Beek. The McDonald's prep lab in 2011, showing preparators at work.