In early 1942, Ted Petry was recruited out of high school to a secret government project at the University of Chicago, told only that it had “something to do with the war effort.” Little did the 17-year-old from the South Side of Chicago know that the $94-per-month job would be part of a groundbreaking experiment that ushered in the Atomic Age.
Working for Nobel-winning scientists Arthur Compton and Enrico Fermi, Petry played a small but important role in the first controlled, self-sustaining nuclear chain reaction. Working as a messenger and laborer, Petry was one of the people who worked day and night to build the 20-foot reactor of graphite and uranium known as Chicago Pile-1 where the landmark discovery happened.
The last known living person to witness one of the most important scientific experiments of the 20th century, Petry died July 28 at age 94.
‘You didn’t question too much’
Petry first got involved with the atomic project when a recruiter visited Tilden Technical High School, where he was a graduating senior. He became a self-described “go-fer” for the UChicago project, one of 30 or so young men hired as laborers. Day and night, they stacked the tons of wood that would support the atomic pile; cut and moved the 45,000 graphite blocks that formed its lattice structure; and used a hydraulic press to turn uranium powder into thousands of baseball-sized spheres that formed part of the reactor’s fuel.
All along, Petry said he never asked the intended use of all the construction work. “A lot of people worked there and left without any knowledge of what was going on,” he said. “You didn’t question too much.”
That included when Petry saw workers jackhammering doorways into the West Stands of Stagg large enough for people to walk through. “If the pile went critical, and they couldn’t control it,” Petry recalled, “they said: ‘Get out through those things and head for Indiana.’”