You have come to one of our major works. Think of the previous pages as introductory. We've given you an idea of how our computer art practice started. We've suggested a few basic ideas. All that leads to the above drawing.

As I write on Friday, January 18, 2008, this drawing is on the wall of the Leigh and Mary Block Museum of Northwestern University, Evanston, Illinois, part of the Imaging by Number exhibition. It will be there until April 6, then will travel to parts currently unknown to me. After traveling it will return to the collection of the Spencer Art Museum, University of Kansas, Lawrence, Kansas.

The drawing was made by a machine called a "pen plotter," which moved a roll of paper forward and a drafting pen left and right. All this was under control of a computer program I wrote.

Our next ideas about algorithmic drawing should be clear in the detail above.

Hardware and software accidents and errors are an accepted part of our art practice. The "machine" and "mathematical" art I've seen tends to be clean and regular. Everything is under control and predictable. Lines are smooth. Forms are located correctly.

Our drawings do not look perfectly machine made. These accidents and errors suggest handmade rather than machine made art.

Look at the black lines in the detail. A line starts at the bottom, draws upwards and then curls to the left. But sometimes a line intersects another line and stops. However, intersection is not consistent. Some lines stop, some continue. There's no clear reason for stopping or continuing.

If you think of the process not as drawing a line, but as laying out fence posts, you'll see what is happening. If you construct a line of fence posts, you might hit a post in a previous line and stop, or you may just sail through without stopping. To me this suggests a real person doing some task imperfectly.

Look at the ochre lines in the lower right of the detail. Some of them end in a blob of ink, where the pen was not picked up the way it was programmed. Look at the two long, horizontal ochre lines. These are not in the code. Again the pen pickup did not do what it was supposed to do. Each of these errors gives a sort of hand made look to the drawing.

One more idea: surprise and wonder. In all of our computer art activity there has been some necessary planning. I start writing a program with ideas in mind. But often what comes out is a complete surprise. And for Colette there is a real sense of wonder and newness. Colette: "Why does it look like that?" "Gosh, I don't know." "Keep it."

And one more thing. Although it does not immediately seem like a big deal, we have used line intersection a lot. More examples later.