E Day 1964 50th Anniversary

Black text and illustrations of a balloon, airplane, buildings and a rocket on a blue and yellow background

E-Day, or Engineers' Day, is an annual celebration of engineers and engineering. Observed at universities across the United States, the event generally involves activities such as engineering competitions, demonstrations, lectures, and banquets.

Since its inception in 1914, E-Day at the University of Minnesota has been organized by a once-secret society called Plumb Bob. The oldest organization on campus, Plumb Bob professes a tongue-in-cheek devotion to St. Patrick, the patron saint of engineers. Plumb Bob may have roots in an even older St. Patrick's Day tradition wherein engineering students at various universities used to cut classes to parade loudly around campus, supposedly in honor of their patron saint.

Today, E-Day at the University of Minnesota is known as CSE Week, to reflect both an expanded calendar of activities and the event's sponsoring department, the College of Science and Engineering. Plumb Bob is now a leadership society with open membership.