The word "nomogram," meaning the "law in graphical form," properly includes alignment diagrams, network charts, and many other graphical forms. By the 1950s, the term "nomogram" came to refer to alignment diagrams exclusively. In this first broad compiling of American nomograms, approximately seventeen hundred alignment diagrams, network charts, and other graphical forms from 97 technical journals are presented, conveniently indexed. Only those technical periodicals were searched which patently favored the publication of this type of diagram. The years covered by this Index are from 1923 through 1949.