Dealers of Lightning: Xerox PARC and the Dawn of the Computer Age

by Michael A. Hiltzik

Metcalfe himself did not realize the extent to which his offspring had become a indispensable part of PARC’s lifestyle until one day shortly after EARS was launched. After accidentally disabling the ether by removing a piece of hardware he noticed “one after another of my colleagues popping up, wondering why the network was down.”

Metcalfe’s departure rattled the PARC staff like a tremor on the San Andreas fault. This was not only because he was the first top computer scientist to quit PARC since its founding five years earlier. More important, his resignation provided the first hint that while they had buried themselves in their research Camelot, a whole new world had sprung up outside—and that it would welcome them and their knowledge. What they could not know was that in a very short time Metcalfe would be back.

Their first step was to do something PARC had never tried before: They analyzed how non-engineers would actually use a computer. This survey was conducted back at Ginn, to which Mott returned with an Alto display, keyboard, and mouse. He installed them as a sort of dummy setup (the machine was nonfunctional) and invited editors to seat themselves in front of the equipment, imagine they were editing on-line, and describe what they expected it to do. “They were a little skeptical,” he recalled. “But—surprise, surprise—what you got was them wanting the machine to mimic what they would do on paper.”

In every way possible, Gypsy mimicked Ginn’s customary routines. The system retained multiple versions and drafts of every file and displayed them as a list. An editor could use the mouse to scroll down the list and click on the desired version to open it. (This was the first time the mouse was used as it is today, to execute point-and-click operations; Engelbart’s system and Bravo both used it simply to position the cursor within a block of text.)

For all their coolness as killer apps, Bravo and Gypsy only scratched the surface of the Alto’s vast capabilities. Although it was not the first machine small enough to be used by an individual—the LINC had been there before—the Alto was the first one deliberately designed as a general-purpose “personal” appliance: individualistic and infinitely customizable. The computer was no longer a machine to which man had to adapt, but one endlessly adaptable to every user’s needs.

Linked by Ethernet to each other, to printers, and to a host of other devices such as video displays and organ keyboards, the Altos lit PARC’s creative fuse. Thacker had designed the first custom application, a program called “SIL” (for “Simple Illustrator”) that automated the process of laying out computer circuits and allowed schematics to be translated directly into printed boards. But scores more were right behind. There were “Draw” by Patrick Beaudelaire and “Markup” by William Newman, which picked up where Ivan Sutherland’s “Sketchpad” left off by giving users the power to place freehand drawings directly onto the bitmapped screen. (Of course, where Sutherland’s program worked only on the lone TX—2 at MIT, these would run on any Alto.) There were programs to compose music and animation, to format text documents, and to assist the writing of more programs, and dozens of programs in Smalltalk.

And there they communicated almost nonstop, a digital chatter that would be the envy of today’s Internet junkies. On the Alto network Xerox employees started the first on-line clubs, played the first networked computer games, even completed the first joint research projects without ever meeting their partners face to face. “At PARC I received my first electronic junk mail, my first electronic job acceptance, and first electronic obituary,” recalled one lab supervisor.

Raised on time-sharing, most of PARC’s computer scientists had trouble getting acclimated to the experience of having computer cycles at their personal disposal. A few even felt a twinge of guilt the first time they turned their backs on an idle Alto, as though they were leaving food on the table while others starved. But for the first time in the history of computing, resources were abundant enough to waste.

“Right about that first year at PARC, under psychotherapy, I discovered I was confusing my talent with my temperament,” he said. “I didn’t have the temperament of a programmer. I realized I needed a group.” This epiphany resembled that of a poet suddenly finding his voice. Like all the self-educated, having once grasped an idea Kay was impatient to move onto the next. He was a man of bifurcated nature, simultaneously a peerless formulator of theory and an instinctive craftsman with a short attention span. Having spent decades as an intellectual lone wolf, Kay redirected his gift for communicating enthusiasm toward the goal of attracting followers, often at the university lectures for which he was much in demand.

Kay had not been daydreaming when he told Ingalls about his plans for a new computer language. What he had in mind would become perhaps the first project in his life he would see through to fruition. Dan Ingalls, it turned out, was the person he needed to make it happen.

By mid—1973 Kay’s so-called “Learning Research Group” numbered eight. They were so miscellaneous in their skills and credentials that Bob Taylor took to calling them, not entirely facetiously, “the lunatic fringe.”

One of the office machines there was an elaborate electric typewriter that could do minimal text formatting through the application of a complicated sequence of keystrokes. No one ever utilized the beastly device’s capability except Merry, who was caught at it one day by Alan Kay. “You’re a programmer!” he exclaimed. “No kidding,” she said. Impressed by the natural skills of this secretary smuggled over from the physics lab, Kay gave her a few hours of rudimentary training. After that it was a relatively simple matter to get her assigned to his group.

He did not care if his recruits had doctorates—although he certainly employed a high percentage of academically gifted scientists and engineers—but he monitored their points of view meticulously.

Like Taylor, he believed strongly that a lab’s success depended on a shared vision. But he was determined to avoid Taylor’s tendency toward militaristic discipline.

No corner of PARC generated anything like the Kay group’s free-wheeling mania. “It was an amazingly seductive environment,” recalled Merry. “I was there late at night all the time. People were so full of ideas and excitement, and of course everybody knew more than anybody else about how the world was supposed to be.”

Even back home, Kay recalled, the group spent much of the daytime “outside of PARC, playing tennis, bike-riding, drinking beer, eating Chinese food, and constantly talking about the Dynabook and its potential to amplify human reach and bring new ways of thinking to a faltering civilization that desperately needed it (that kind of goal was common in California in the aftermath of the Sixties).”

But Ingalls was an instinctive master at picking out the subset of Ideaspace that was actually doable, and doing it. Even before the first Altos were designed and built, Ingalls had started working on one such subset. By the time the machines were finished, his efforts had yielded the masterpiece of computer science called Smalltalk. Smalltalk would make Kay’s reputation more than Ingalls’s, but Kay never forgot who transformed it from idea to reality. “Nobody would ever have heard of me,” he said later, “if it wasn’t for Dan Ingalls.”

Kay’s goal was to create a language that enabled the programmer to arrive at a simple result by a simple path, regardless of the complex operations taking place beneath the surface. He called this “hiding the details.” After all, one does not need to know how a television works to be able to switch it on and find one’s favorite show—why should it be necessary to know all the details of data and procedure to map a simple image to a computer screen?

Just as clicking the “on” button of a remote control sends the TV a “message” to turn itself on, in Kay’s system one sends the object “3” the message “+ 4.” The object knows to interpret that as a simple addition, and returns 7. This may seem complex at first. But in contrast to traditional languages, object-oriented programming becomes relatively simpler as the data and operations become more complex. The reason is that the underlying calculations always remain hidden within the object, never needing to be explicitly invoked by the programmer. The object “John,” for example, needs only to be sent the message “+ Mary” to know that “+” in this context can mean only one thing: to append “Mary” to itself after a comma.

Once the Alto came along, this process picked up speed as Kay’s group enhanced Smalltalk with graphical capabilities that exceeded anything else being developed at PARC.

But once Kay finally got all his machines retrofitted with adequate memory, Smalltalk fulfilled all its developers’ expectations. While the CSL engineers busied themselves with programs to format the same dull text-heavy documents as fast as they could make the Altos run, the lunatic fringe worked the machines’ graphical capabilities to the bone. A typical Learning Research Group program was no blob of black-on-white text but a carnival of drawings, half-tone photographs, even animated pictures. “Objects mean multimedia documents,” Kay would say. “You almost get them for free.” As a result, the group’s programs tended to favor the artist over the scientist. An LRG engineer named Bob Shur had programmed, with Thacker’s help, a musical synthesizer capability into the Alto that allowed the machine to output twelve real-time voices at once, an astonishing capability for a machine of the Alto’s scale.

Then, in the fall of 1975, Ted Kaehler, although no musician himself, developed a program called “Twang.” This was a visual interface to a number of music synthesizer programs that could capture, compose, edit, and replay music on the Alto. Twang used a nontraditional notation, black bars of differing lengths and locations to indicate differing tonic and rhythmic values, that deliberately resembled the perforations on a player piano roll. Twang was unusual in that it worked virtually in real time. All previous computer music programs, including the pioneering “FM” developed by John Chowning at Stanford, had to be compiled, meaning that several hours of programming and debugging were necessary to produce a five-minute riff.

The encounter was mutually enlightening. Although these youngsters had for the most part grown up in privileged and brainy homes, they were surprised to come across grownups so guilelessly interested in their burgeoning intellects.

The scientists, some with young families of their own but few with teenagers around the house, found it eye-opening to deal with twelve-and thirteen-year-olds who grasped the basics of programming instinctively.

The California magazine New West once quoted him as saying that Xerox “doesn’t understand” computers and its executives “really don’t have any idea what I’m doing here,” forcing Jack Goldman to reassure his fellow Xerox executives in writing that “Dr. Alan Kay is a recognized outstanding scientist in his field, albeit somewhat native and unorthodox in his dealings with the press.”

“Our mission was to really make this hardware do what it was supposed to do,” recalled Kaehler. “Make it suitable for kids, flashy and wonderful, really responsive. And CSL was more concerned with hard-core computer science issues. They wound up not making that many innovations in the interface. We knew we couldn’t design hardware like them, but we could make the interface much more interactive.”

The answer, unfortunately, was that the Alto’s 8½-by-11-inch screen encompassed just so much physical real estate—the space of a single sheet of writing paper. That limitation, as it happened, led directly to one of their most important contributions to the look of the computer screen—the concept of overlapping windows. The idea began by thinking of the screen in terms of a physical desktop. People in offices got around the same problem of too much paper and not enough room, Kay reasoned, by piling pages on top of one another. The analogous procedure would be to pile up small images on the screen—perhaps in some way that allowed the user to keep track of how many sheets, or projects, or windows, were open at once and to summon the most important one instantly to the top of the pile.

The solution came in the form of a brilliant feat of coding Ingalls called “BitBlt,” an abbreviation of the term “bit boundary block transfer” that was pronounced “bitblit.” BitBlt was a way to shift whole rectangles, or blocks, of the bitmap from one location to another in a single operation. It enabled the system to bypass the tedium of delving into memory, locating all the components of the rectangular image, and changing them one by one; and thus cut out most of the computation that had made full-bitmap procedures so slow. Suddenly graphical changes on the display were faster, more direct, and in computing terms vastly cheaper.

Like the wheel or the gothic arch, BitBlt was one of those discoveries that was nonintuitive in advance, obvious in retrospect, and ultimately adaptable to an infinity of uses.

Only then did Ingalls realize what had happened. In the midst of the edit he had instinctively pressed the middle button of his mouse. As if from nowhere, a small rectangle had appeared on the screen listing several commands. Ingalls had selected “cut” and released the button, whereupon the tiny rectangle instantly disappeared (along with the selected text to be deleted). It was something they called the “pop-up menu,” the forerunner of a device common to almost every Windows or Macintosh program today. “It flashed and disappeared,” he recalled. “That was really a wonderful moment, and it was all done in a half a second.”

The machine was called Superpaint. It deserves a place in history as the only invention too farsighted even for PARC’s Computer Science Lab. And all because it thought in color.

The finished product was the first fully video-compatible frame buffer ever built. It was also a vector apart from the computer his colleagues had assembled in the basement. Where the Alto fit under a desk, Superpaint occupied two cabinets, each standing five feet tall and holding thirty-three memory cards. Its nearly two and a half million memory bits (in semiconductor chips worth about $100,000) meant that each pixel in a video frame with a resolution of 486 by 640 pixels could be addressed by eight bits. The system required two separate display monitors, one to show the image to be manipulated and the second a menu of electronic “paintbrushes” with which it could be altered in color or pattern.

Superpaint was a uniquely agile and adaptable graphical tool. One could “grab” a frame from a videotape, disc, or directly off a television screen and manhandle it by changing its colors, flipping or reversing the image, bleeding it across the screen, even animating it.

“Everyone on that side of the house was interested in documents,” Shoup recalled. “Documents are pretty much black marks on white paper. Color meant TV, and that was some other world.”

The Computer Science Lab was a collection of engineers who weighed everything pitilessly against the question: How will this get us closer to our goal? They had committed themselves to developing Xerox’s office of the future, and anything that diverted their attention or served an alternative goal had to be discarded or obliterated.