Of course, Kekulé may have made up the story about his vision. He told it only once for the public record, late in his life, nearly thirty years after the event. Some suspect he related the story of the whirling snake to solidify his priority for the discovery. He did not publish his findings until some years later, in part because grief over the death of his wife Stephanie left him sick, unable to work.[ii]
But the Kekulé story persists as one of chemistry’s founding myths, and the image of benzene confirmed his prescience. Scientists at IBM created the picture with a scanning tunneling microscope, which uses an atom-sized probe to track variations in electrical current between it and the surface being mapped.[iii]
The resulting figure looked startlingly like Kekulé’s daydream, and the simple hexagonal line drawings used ever since to represent benzene. It confirmed the reality of what before existed only as idea. Such an image “gives the feeling that one could simply reach out and touch the atoms,” says the chemist David Goodsell.[iv]
But no one has ever seen or touched an atom, and no one ever will. Microscopes do not record pictures of molecules. The machine returns a series of numbers “unreadable to most people, even scientists,” writes the chemist Tami Spector. Technicians use computers to transform the numbers into an image, a sort of topographical map of electrical signals.
Researchers, scientific journal editors and the popular press blank out this mediating factor. They present the figure as if it were an actual picture of atoms and molecules. Scanning microscopes yield numeric data that are transformed “into images disguised as photographs,” writes Spector.[v]
Why? Desire. To see, reveal—to know, a word that is very old. To look with one’s own eyes. It comes as a kind of force like lust, doesn’t it? But never to be satisfied, unless we fake it. Spector: Molecules exist in an “inherently unknowable space … inaccessible but ripe with imaginative yearning.”[vi]
Yearn. It’s an old word also. Kekulé yearned to know molecules. He thought of them constantly. He dreamed about them. He pictured molecules and then built them using sticks and balls made of wood and metal. Kekulé and other nineteenth century chemists created a visual vocabulary for showing how atoms join up. They did not consider these actual models of molecules, only as maps, or keys to their functions. Kekulé didn’t even believe in atoms, at least not as the tiny particles people imagine.[vii]
The valence diagrams he and others pioneered remain the common currency for conveying chemical information. They are taken for granted as actual depictions. But Spector notes they are far from realistic: “they communicate a sense of the molecule’s spatial geometry … [but] reduce experimental evidence, stripping it bare of noise, impurities … presenting instead an idealized abstraction of a single, motionless, molecule.”[viii]
More sophisticated technology creates more sophisticated images, but they remain extrapolations, constructions of entities human senses will never reach. Still, the desire persists. The word microscope itself implies sight.
An article from 2009 titled “Keep your eye on the atom” opens with this: “How many times have chemists wished for a microscope so powerful that they could see right down to the atomic level of an individual molecule? Scientists at IBM Research in Zurich, Switzerland have now achieved this elusive goal.”
The rhetoric of sight saturates molecular discovery. The image of pentacene — five-fused benzene rings — “speaks for itself,” says the article. Except, apparently, it doesn’t. The rendering is grey and fuzzy. To aid in translation, the editors placed above the microscope image a traditional “ball-and-stick” structure — a digital analogue of Kekulé’s nineteenth century models. Seeing is believing, if belief entails doubt. [ix]
I sent Dr. Tami Spector an email. I explained I was a poet and asked her some questions. She didn’t respond to me. Her name of course conjures image in its most ephemeral sense, a ghost. She writes that what scientists want most, even more than pictures of atoms and molecules, is to capture them in the act of transforming. It is the instant of change, the moment of the swerve they most long for.[x]
In spring 2013, the Lawrence Berkeley National Lab issued a press release headlined “A chemical reaction caught in the act.” It claimed scientists had captured the first-ever high-resolution images of a molecule—benzene rings—breaking and reforming chemical bonds.[xi]
The point of the research was to try and engineer graphene, a single layer of carbon atoms bonded in hexagons. That failed, but the news was not the research, it was the imagery. The press release quotes lead scientist Felix Fischer “We weren’t thinking about making beautiful images; the reactions themselves were the goal.” But, he adds, they needed “to really see what was happening at the single-atom level.”
To really see. But Dr. Fischer uses a metaphor of blindness, comparing the atomic-force microscope moving over the surface to reading Braille. “The resulting images,” the press release reports, “bore a startling resemblance to diagrams from a textbook or on the blackboard, used to teach chemistry, except here no imagination is required.”
Science has vanquished the blank, the gap between mind and world, delivered the un-seeable to the human eyeball on a surface of silver. Says Dr. Fischer: “What you see is what you have,” which means “possess,” and comes from the root word for grasp.
Of course the reaction itself can’t be captured. What the images show instead is the “before” and “after” bridged by an arrow. All the meaning hangs on that black connector. Carry us there, O strike us, arrow, arrow. Lust of the flesshe, lust of the eye. All images are after.[xii]
[i] Malcolm W. Browne, “A Pervasive Molecule is Captured in a Photograph,” The New York Times, August 16, 1988: http://www.nytimes.com/1988/08/16/science/a-pervasive-molecule-is-captured-in-a-photograph.html?pagewanted=all&src=pm
[ii] Image and Reality, 198-199
Russell D. Larsen, University of Pittsburgh, “Kekulé’s Benzolfest Speech: A Fertile Resource for the Sociology of Science,” Chapter 13 in Kekulé Riddle, 184
[iii] Tami I. Specter, “Nanoaesthetics: From the Molecular to the Machine,” Representations, Vol. 117, No. 1 (Winter 2012), 1-29.
[iv] David Goodsell, “Fact and Fantasy in Nanotech Imagery,” Leonardo, Vol. 42, No.1 (2009), 52-57.
[v] Nanoaesthetics, 21.
[vi] Nanoaesthetics, 15
[vii] Nanoaesthetics, 3
Image and Reality, 225
[viii] Nanoaesthetics, 8.
[x] Nanoaesthetics, 14-15
[xii] “Nanoaesthetics, 14-15
Poethical Wager, 10.