Duncan Campbell Lyle, who served as assistant principal under Col. Allan and was appointed principal upon Allan’s death, paid particular attention to the grounds and the effectiveness of classroom teaching. Lyle, who gave everyone a nickname, earned his moniker “Old Man Lyle” before the age of 40. He was a favorite of the students and he launched The Week during his tenure.
Lyle took a particular interest in the futures and successes of the young men who passed through McDonogh, and as such, he created individual scrapbooks about them filled with academic information, club memberships, and clippings from The Week. After their graduation, Lyle corresponded with many alumni and added their correspondence to their scrapbooks. Those who served in World War I often sent letters from the frontlines detailing the struggles of war, life in the trenches, and the comradery of the McDonogh alumni who were serving. Four years after being appointed principal, Lyle decided to return to teaching. Old Man Lyle continued to serve the school faithfully for 46 years as a faculty member. Late in his life, he returned to campus where he died in 1938.
