Can Flecks of charcoal in soils and hearths be concentrated into a usable sample for radiocarbon dating? It is impracticable to ship large volumes of soil with low carbon content from distant sites, yet dating them may be most important. This question was informally discussed following the Wenner-Gren Conference on African Prehistory held at the University of Chicago in February, 1953, and as a result Robert J. Braidwood proposed that an experimental field laboratory be established that summer at an excavation where water and electricity were available if needed. The Department of Anthropology of the University of Chicago and the Illinois State Museum were sponsoring the excavation of a rock shelter near Modoc, Illinois, and I was invited to conduct experiments there, trying out any technics that I wished. It was hoped that these experiments would result in establishing a simple procedure that could be used in many parts of the world for procuring radiocarbon samples.