American Scientists: A Picture of Minds at Work

When Ethel Kessler was tasked with designing the third release in the American Scientists series, she faced a challenge. She wanted to continue the general approach of the previous two issues, which had depicted portraits of the honored scientists set against backgrounds representing their research. But in many cases, the scientific discoveries of the 2011 subjects did not easily lend themselves to visual representation.

Asa Gray’s contributions to botany were the easiest to illustrate. A circa-1860s photograph of Gray is shown with an image of Shortia galacifolia. Gray’s publications standardized the classification of North American plants, but this tiny Appalachian flower was his favorite discovery. He spent decades hunting for it and named it Shortia after botanist Charles Short.

Scholars like Maria Goeppert Mayer, however, did not make such tangible discoveries. Mayer shared the 1963 Nobel Prize in physics for her theoretical work concerning the structure of the atomic nucleus.

“It’s in her mind,” Kessler says. “We’re not going to be able to show a picture of something that she invented.” So Kessler turned to Mayer’s own diagrams, the closest thing to an illustration of her mental process.

Kessler took a similar approach for chemist Melvin Calvin and biochemist Severo Ochoa. The portraits of both men were taken from photographs showing them using laboratory equipment. But Kessler wanted to feature their particular achievements, not a generic test tube. “It’s not just an experiment,” she explains. “They were thinking things that people hadn’t thought yet.”

For Calvin, Kessler featured a diagram of the carbon cycle, often called the “Calvin cycle” in his honor. In Ochoa’s case, Kessler used a scheme of viral genetic material to illustrate the scientist’s research on RNA. While such schematics are not typical stamp artwork, Kessler and the stamp consultants felt it was important to depict these discoveries accurately and specifically.

Inspired by the colors and collage-like layering of European currency, Kessler worked with designer Greg Berger to blend the scientists’ portraits with the other visual elements.

For Berger, who remembers visiting his father’s laboratory as a child, layering was another way to show the scientists’ minds at work. “We wanted a more subtle effect,” he explains, “where you could get a feeling of them being immersed in their work.”

To add to the layering, Kessler and Berger added a second portrait to each stamp design. These images fade into the symbols of research, suggesting that the scientists are deep in thought, absorbed with their ideas.

The result is a subtle variation in the American Scientists series — one that draws us into the complex achievements of some of America’s greatest thinkers and celebrates the beauty of a mind at work.

View the entire American Scientists series.