Ross, Denman Waldo, 1853-1935.
A Theory of Pure Design; harmony, balance, rhythm; with illustrations and diagrams.
Boston and New York, Houghton, Mifflin and Company, 1907.

This is a graduate level text; an interesting but difficult read. But if design is you life’s work–or your passion—you should be familiar with this work. In 1918-19 Ross was introduced to the work on Jay Hambidge on Dynamic Symmetry. Ross theories began to evolve but unfortunately Ross did not publish a new work. See Federated Council on Art Education, Committee on Terminology, Report of the Committee on Terminology, 1929. (cat 8.12)