John C. Rock, a Harvard professor of gynecology, was the co-inventor of the birth control pill and a pioneer of in-vitro fertilization. Harvard's Center for the History of Medicine is holding an exhibition of his papers and artifacts, including two devices to help with "family planning" during a time when the only legal form of birth control in Massachusetts was the rhythm method. Above is "The Rythmeter," circa 1944. "A Pioneer in Family Planning" (via Mother Jones)