August 2, 2004

The color indigo


Bill Gruber is professor and chair of English.

I'm sure this has happened to you, because it happens on every flight that lasts more than three hours. As the video pods descend from the ceiling of the cabin, the flight attendants advertise the in-flight movie. They've made the speech a thousand times before, and invariably it closes with the suggestion that all passengers, including those who want simply to read, snooze or just be left alone, lower their window shades to reduce the glare on the screens inside the cabin.

It's a request I've never honored, even on flights where the only things to see below the aircraft are the tops of the clouds that blanket the North Atlantic. Sometimes I'm the only one with the window shade up. Like most Americans living in the 21st century, I've logged so many hours in commercial jets that flight is a routine part of life. But I never tire of the view out the window.

Most writers who celebrate the glory of flight talk about the novelty of the aerial perspective, about the gestalt-altering experience of seeing the earth from strange angles and in unexpected proportions. But I'm just as happy, sitting by the window at 37,000 feet, to look up instead of down.

Angling outward and up against the dome of the sky, the wing becomes a scale against which to measure the changing hues at the blue end of the spectrum. These are colors almost never visible anywhere else. From the surface of the earth, the sky appears uniformly and mildly blue, the way it looks in children's drawings or in picture postcards; this is because of the scattering effect of the atmosphere on the shorter (or blue) wavelengths of light.

But the higher you fly, the less light is scattered by the thinner atmosphere, and the easier it becomes for human eyes to sort out the multitude of colors at the nether reaches of visible light. Up there, the shades of blue proliferate wonderfully. They pass from cerulean to azure to indigo, changing finally to shades of purple: lavender, mauve, eventually an unworldly violet. Together they form a curtain of colors so rare and pure they seem more invented than real. Words can't describe such colors because, well, they can't.

Any language has its own peculiar blind spots, and if you don't name a thing, there's a sense in which it's really not there. Colors are notoriously shifty in this respect. We distinguish commonly between gray, green and yellow, but Anglo Saxons, who had no use, among other things, for traffic lights, called all these colors simply "fallow."

Wealthy arts patrons in 15th century Italy included in the commissioning of contracts for portrait painters, in addition to instructions about the subject, stipulations as to the kinds and colors of paint that the artists were to use. The painters' clients were often concerned about gold and silver--the splendor of gilt highlights did not come cheap--but much more remarkable was their fondness for the color blue.

In the contract for Domenico Bigordi Ghirlandaio's Adoration of the Magi, for example, the purchaser stipulated that the painter "must colour the panel at his own expense with good colours and with powdered gold on such ornaments as demand it, with any other expense incurred on the same panel, and the blue must be ultramarine of the value about four florins the ounce."

This blue, which was made from powdered lapis lazuli imported from the Levant, was a color of unusual richness; sensuous, even slightly dangerous, it gave to paintings a hue deeper and more exotic than blues made from carbonate of copper. Contracts such as these, writes Michael Baxandall, are more than records of commercial transactions; "they point," he says, "to a sophistication about blues, a capacity to discriminate between one and another, with which our own culture does not equip us."

It's humbling to think that our ancestors had a greater capacity for sensual experience than we do, but that sometimes seems to be the case. Once my son brought home from elementary school a science worksheet; his assignment was to fill in the colors of the rainbow. There were six blank arcs ready for coloring, one each, he said, for red, orange, yellow, green, blue and purple. What happened to indigo? I asked. He said those were the only colors he'd been taught. I told him that when I was in elementary school I learned that there were seven colors in the rainbow, that between blue and violet was a distinct band called ultramarine, or indigo, and I told him further that I learned to accept this on the authority of the person who had first defined the spectrum of visible light, Isaac Newton.

I was going to raise a fuss with the DeKalb County schools for dumbing down the rainbow, but while I was boning up for my encounter with my son's teacher I discovered that subject was murkier than I had thought. Newton indeed described seven colors when he passed a ray of sunlight through a prism--he identified red, orange, yellow, green, cyan, ultramarine and violet. Nevertheless, his separation of visible light into seven distinct visual zones seems to have been less than scientific.

Newton's first thought was to name five colors. But this great man of science yearned for the universe to be structured according to mathematical and musical principles, and so ultimately he saw--or decided he saw--seven spectral colors, a number important both in philosophy and theology, and which, not incidentally, corresponded to the number of intervals in an octave.

he Babylonian word for this blue we are no longer taught to see was uqnu, and the Babylonians, according to John Berger, prized the color for its overwhelming sensuousness; one could speak, in that time, of both male and female varieties of the color, the darker one being the male.

How strange and sad to think of a color divided against itself in the way of the sexes; stranger and sadder still to wonder why we habitually lower the shade on it. A rose by any other name may smell as sweet, but to see a color truly we need to carve out mental space for it with words.

Thus I think it's a hopeful sign that Crayola recently restored "indigo" to its largest box of children's crayons. The color itself is not new, apparently, just the name. The manufacturers state on their website that "indigo" has been available to the young artiste all along, just hidden under a different identity.

Like so many things, this too comes down to politics, and the history of indigo's disappearance and reappearance on the palette of the Crayola Corp. is a revealing commentary on how words follow fashion and how thought, in turn, follows the words. Small wonder we haven't been able to see it: During the latter part of the 20th century, Crayola reports, the crayon now called indigo bore the emphatically uncelestial name "thistle," boxed along with a host of other lackluster but mindlessly "natural" colors like "fern," "eggplant," "manatee" and--oh, say it ain't so!--"macaroni and cheese."

This essay first appeared in the July 2004 edition of Loose Canons , the English department newsletter, and is reprinted with permission.