Oliver Byrne’s life, prolific publication record, and pedagogical philosophy have intrigued the authors for decades. This article shares a little known Victorian mathematician with a wider audience and describes how his *The First Six Books of the Elements of Euclid in Which Coloured Diagrams and Symbols Are Used Instead of Letters for the Greater Ease of Learners,* in particular, provides an interesting example of the use of color and diagrams in the teaching of mathematics. Included are suggestions about how excerpts from his *Euclid in Colours* can be (and have been) used for lessons and projects in geometry classes, and also for discussions of history and pedagogy in courses in mathematics history and mathematics education. Software such as *Geometer’s Sketchpad,* often used to teach geometry classes today, is also in the spirit of Byrne’s pedagogical philosophy and use of color, which, in his own words, “engraves the knowledge with a beam of light.”^{116} During his lifetime, Byrne’s mathematical work was sometimes ignored or greeted with ridicule from his contemporaries. He also battled financial difficulties throughout his life, encountered nationalistic prejudice as an Irishman, and faced serious health issues in his later years. Despite the many challenges he encountered in his day, today Oliver Byrne can be recognized as a true pedagogical visionary, a true Matisse of Mathematics.

Susan M. Hawes is a genealogist based in Portland, Maine. She holds a Bachelor of Arts from the University of Colorado at Boulder. Her biographical research on Oliver Byrne stems from studying her great-grandfather Austin Thomas Byrne (1859-1934), surveyor, civil engineer, and author. Artifacts Austin Byrne left to the family include three of Oliver Byrne’s books.

Dr. Sid Kolpas has taught Mathematics for 44 years at the Elementary, Secondary, and College levels. He earned a BA (Magna Cum Laude) and MS in Mathematics from California State University, Northridge, and an EdD in Mathematics Curriculum and Instruction and Educational Psychology from the University of Southern California. In 1984 he received the McLuhan Distinguished Teachers Award. In 1991 he was selected as Burbank Teacher of the Year. In 2004 he received the Distinguished Faculty Award from Glendale Community College. In 2010, he received the prestigious Hayward Award for Excellence in Education given by the Board of Governors of the California Community Colleges. His interests include the use of technology in teaching, and Mathematics History. He has collected antiquarian mathematics books and ephemera for the past 44 years, incorporating his collection in his teaching. He is currently an Assistant Professor of Mathematics at Delaware County Community College in Media, Pennsylvania where he is the Custodian of the Liberal Arts Mathematics and Statistics curriculum.

116 *The First Six Books of the Elements of Euclid in Which Coloured Diagrams and Symbols Are Used Instead of Letters for the Greater Ease of Learners *(London: William Pickering, 1847), xii.