Blood, Dirt, and Nomograms: A Particular History of Graphs

L. J. Henderson, a Harvard physiologist and the first president of the History of Science Society, attempted to analyze mammalian blood solely as a physical-chemical substance. He found that the only way he could describe a chemical system as complicated as blood was by a diagram called a "nomogram." This lecture tells the history of Henderson's nomogram and of nomograms in general. It describes the origins of graphs in the eighteenth century, their development in nineteenth-century engineering practice, and their importance in the twentieth century for describing physical and chemical systems.