Friday afternoons were reserved for educational films back when I was in grade school. We’d sit on the floor in a darkened room, facing a pull-down screen, and listen to the teacher fumbling behind us at the projector. The flapping celluloid sound meant the film was threading through gears and past the lens, and then presto! We were in movie heaven.

One image from those films keeps popping up in my mind’s eye: a cartoon-rendered cornfield with dashed lines moving from the soil into the plants. A floating Geiger counter leans into a cornstalk as a man’s benevolent voice explains how uranium can be tracked in living things, and the possibilities this opens up for all of us.

The message my child brain heard was that technology could work wonders, even with something scary like uranium. Up till then I’d dimly associated it with Russians and bomb shelters. Now, the voice assured us, it was OK because technology would make it OK.

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