The Assembly Room or Fireplace Room, as it was sometimes called, was the only formal meeting space at the Lab. It was here that one of the most significant of the month-long Symposia, “Heredity and Variation in Microorganisms,” was held in 1946, setting the stage for the birth of molecular genetics. That year, presentations were given by Max Delbrück, Alfred Hershey, Salvador Luria, Harriet Taylor, and other influential scientists. The symposia continued annually in Blackford Hall (except during the war years of WWII) until 1953 when the growing number of attendees necessitated a larger meeting space.