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The Sciences


In Living Color


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Separation AnxietyPhotograph from Getty.

Full-color images like the passel of peppers seen at right are printed using dots of four colors: cyan (blue), magenta (red), yellow, and black. Before a color photograph is printed, it is separated into four black-and-white images, or plates, one for each of the four printing colors, as shown in the small images below. Notice that the green pepper appears extremely dark in the cyan separation (green is cyan plus yellow), while the red pepper is dark in the magenta separation (red is magenta plus yellow). The four separations are then printed on top of one another in the four ink colors to produce a full-color image.

When separations are scrambled—for instance, when the cyan separation, or plate, is used for magenta ink—strange colors result in the final image. The cyan and magenta plates were reversed in the first photograph shown below left, causing green areas to look orange, and vice versa. Which two separations were reversed in each of the other three images?


Rainbow CoalitionIn the figure below left, six different colors appear in every row, column, and outlined region. Can you color the squares in the three other figures so there are six different colors in every row, column, and outlined region? Make it easier on yourself—use numbers instead of colors to work out the answers.

To get you started, let's fill in the color for the square marked * in puzzle 1. This square can't be colors 1, 2, or 3, because those colors already appear in the same row as *. Similarly, this square can't be colors 4 or 5, because those colors already appear in the same column as *. Therefore, the square must be color 6. Use the same sort of reasoning to determine the colors of the other squares in the grids. We've filled in a few squares to help you out.


Pigments of Imagination Modern painters can head down to the art supply shop and purchase a full spectrum of hues, but colors have not always been so easy to obtain. In his book Bright Earth: Art and the Invention of Color (Farrar, Straus & Giroux, 2002), science writer Philip Ball reports, "Until the 18th century, most artists ground and mixed their own pigments . . . and possessed some considerable skill as practical chemists." For centuries, artists and craftspeople relied on animals, plants, minerals, and at times toxic chemical compounds as the raw materials for their hues. Can you match each swatch below with its chemical origin?

Chemical Origins


Vermilion, the medieval artist's prized red, bettered only in the 20th century


An intense yellow that debuted in the 19th century, used by Claude Monet


Emerald green, whose fumes may have poisoned Napoléon Bonaparte


Egyptian blue, one of the oldest synthetic pigments, required a 1,470°F kiln


A deep blue; first used in antiquity in ceramic glazes and colored glass


Mauve, invented in 1856, launched the modern chemical industry


Tyrian purple, worn in ancient Rome only by high-ranking officials


Black, as it appears in the Lascaux cave paintings



  1. Cadmium, a by-product of zinc smelting

  2. Charcoal

  3. Cobalt

  4. Copper acetoarsenite

  5. Lead carbonate, replaced by the nontoxic alternatives zinc oxide in the 19th century and titanium dioxide in the 20th century

  6. Limestone, malachite or other copper ore, and sand

  7. Mediterranean shellfish; the colorant molecule is chemically similar to that of the Indian pea plant Indigofera

  8. Mercury sulfide, or the mineral cinnabar, the principal ore for mercury; the root of cinnabar sounds similar to that of cinnamon

  9. The first popular synthetic dye, derived from coal tar, a by-product of manufactured gas, which was used in the 19th and early 20th century for lighting and fuel


Want to see the solution to this puzzle?

Let us know what you think of Bogglers: E-mail alternate solutions, comments, and suggestions to

Got new solutions for the puzzle? Want to see other people's solutions? Talk to the puzzle master in his discussion forum at


There are more puzzles and inventions by Scott Kim on his Web site,, where you will also find an archive of his monthly Bogglers columns and other amusements for your mind.

© Copyright 2003 The Walt Disney

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