Copying is the engine of civilization: culture is behavior duplicated. The oldest copier invented by people is language, by which an idea of yours becomes an idea of mine. The second great copying machine was writing. When the Sumerians transposed spoken words into stylus marks on clay tablets more than 5,000 years ago, they hugely extended the human network that language had created. Writing freed copying from the chain of living contact. It made ideas permanent, portable and endlessly reproducible.

Until Johann Gutenberg invented the printing press in the mid-1400s, producing a book in an edition of more than one generally meant writing it out again. Printing with moveable type was not copying, however. Gutenberg couldn’t take a document that already existed, feed it into his printing press and run off facsimiles. The first true mechanical copier was manufactured in 1780, when James Watt, who is better known as the inventor of the modern steam engine, created the copying press. Few people today know what a copying press was, but you may have seen one in an antiques store, where it was perhaps called a book press. A user took a document freshly written in special ink, placed a moistened sheet of translucent paper against the inked surface and squeezed the two sheets together in the press, causing some of the ink from the original to penetrate the second sheet, which could then be read by turning it over and looking through its back.

Copying presses were standard equipment in offices for nearly a century and a half. (Thomas Jefferson used one, and the last president whose official correspondence was copied on one was Calvin Coolidge.) The machines were displaced, beginning in the late 1800s, by a combination of two 19thcentury inventions: the typewriter and carbon paper.

Among the first modern copying machines, introduced in 1950 by 3M, was the Thermo-Fax, and it made a copy by shining infrared light through an original document and a sheet of paper that had been coated with heat-sensitive chemicals. Competing manufacturers soon introduced other copying technologies and marketed machines called Dupliton, Dial- A-Matic Autostat, Verifax, Copease and Copymation. These machines and their successors were welcomed by secretaries, who had no other means of reproducing documents in hand, but each had serious drawbacks. All required expensive chemically treated papers. And all made copies that smelled bad, were hard to read, didn’t last long and tended to curl up into tubes.

None of those machines are still manufactured today. They were all made obsolete by a radically different machine, which had been developed by an obscure photographic-supply company. That company had been founded in 1906 as the Haloid Company and is known today as the Xerox Corporation. In 1959, it introduced an office copier called the Haloid Xerox 914, a machine that, unlike its numerous competitors, made sharp, permanent copies on ordinary paper—a huge breakthrough. The process, which Haloid called xerography (based on Greek words meaning “dry” and “writing”), was so unusual and nonintuitive that physicists who visited the drafty warehouses where the first machines were built sometimes expressed doubt that it was even theoretically feasible.

Remarkably, xerography was conceived by one person— Chester Carlson, a shy, soft-spoken patent attorney, who grew up in almost unspeakable poverty and worked his way through junior college and the California Institute of Technology. He made his discovery in solitude in 1937 and offered it to more than 20 major corporations, among them IBM, General Electric, Eastman Kodak and RCA. All of them turned him down, expressing what he later called “an enthusiastic lack of interest” and thereby passing up the opportunity to manufacture what Fortune magazine would describe as “the most successful product ever marketed in America.”

Carlson’s invention was indeed a commercial triumph. Essentially overnight, people began making copies at a rate that was orders of magnitude higher than anyone had believed possible. And the rate is still growing. In fact, most documents handled by a typical American office worker today are produced xerographically, either on copiers manufactured by Xerox and its competitors or on laser printers, which employ the same process (and were invented, in the 1970s, by a Xerox researcher). This year, the world will produce more than three trillion xerographic copies and laser-printed pages—about 500 for every human on earth.

Xerography eventually made Carlson a very wealthy man. (His royalties amounted to something like a 16th of a cent for every Xerox copy made, worldwide, through 1965.) Nevertheless, he lived simply. He never owned a second home or a second car, and his wife had to urge him not to buy thirdclass train tickets when he traveled in Europe. People who knew him casually seldom suspected that he was rich or even well-to-do; when Carlson told an acquaintance he worked at Xerox, the man assumed he was a factory worker and asked if he belonged to a union. “His real wealth seemed to be composed of the number of things he could easily do without,” his second wife said. He spent the last years of his life quietly giving most of his fortune away. When he died in 1968, among the eulogizers was the secretary-general of the United Nations.

Chester Carlson was born in Seattle in 1906. His parents—Olof Adolph Carlson and Ellen Josephine Hawkins—had grown up on neighboring farms in Grove City, Minnesota, a tiny Swedish farming community about 75 miles west of Minneapolis. Olof was a barber. He suffered severely from arthritis in his spine, and he developed tuberculosis in his 30s. Seeking relief, he moved his wife and 3-year-old son to a brother’s house in California, then to a camp among sand dunes in the Arizona desert, then to an adobe hut on a worthless Mexican farm, then to Los Angeles—where the family spent more than a year living in a single room in the home of a doctor for whom Ellen, now the family’s sole financial support, worked as a housekeeper— then to a dilapidated rented house in San Bernardino. In the fall of 1915, when Chester was 9, Olof decided that cold, rather than heat, might improve his health, and he moved the family again, to a decaying shed in the mountains outside San Bernardino. The snows that winter were three and four feet deep. Each morning, Ellen used a hand mirror to flash a signal to a worried storekeeper in the valley below, to let him know that they had survived another night.

Young Chester knew his father only as an invalid and would remember him as “a bent walking skeleton, who had to spend the greater part of his time lying flat on his back.” Chester, an only child, also said his mother had always somehow managed to make the family’s poverty seem like a game—a challenging puzzle that could be solved with good spirits and ingenuity. Nevertheless, he had a very lonely childhood. During most of the time the family lived in the mountains, he was the only student in the local school. This period, he said, “marked the beginning of a considerable setback in my social development among children of my age.” When the school year ended, Olof—who had now abandoned all hope of improving his health—moved the family back into the valley, where, for the next eight years, they lived in a grim succession of rundown houses.

By the time Chester entered high school, he was his family’s principle provider. Still, he managed to make good grades, especially in science, and began to think seriously about how he might use his talents. He considered gold prospecting, publishing and other occupations before deciding his best chance would be to invent something valuable.

At 15, Chester began jotting down ideas for inventions and making other notes in a pocket diary, a practice he maintained for the rest of his life. He sketched concepts for a rotating billboard, a machine for cleaning shoes and a trick safety pin (which could be made to look as though it had pierced a finger). He was fascinated by printing and the graphic arts. When he was 10, his favorite possession was a toy typewriter. Later, he worked in a print shop and published a magazine, the Amateur Chemists’ Press, for scienceminded classmates. “I was impressed with the tremendous amount of labor involved in getting something into print,” he recalled in a 1965 interview with Joseph J. Ermenc, a Dartmouth professor. “That set me to thinking about easier ways to do that, and I got to thinking about duplicating methods.” During his junior year in high school, his mother—his one source of happiness, encouragement, stability and love— died of tuberculosis, at 53. Her death devastated him; 25 years later, he was almost physically unable to speak of it. “The worst thing that ever happened to me,” he recalled. “I so wanted to be able to give her a few things in life.” By the time he graduated from high school, he and Olof had been reduced to living in a former chicken coop, whose single room had a bare concrete floor. Chester slept outdoors, partly to lessen his own chance of contracting the disease that had killed his mother, on a narrow strip of packed earth between the building and a board fence that ran along the alley, in a sleeping bag that he himself had made.

Carlson worked his way through three years at a nearby junior college, then transferred to Cal Tech, where he majored in physics and supported himself and his father by mowing lawns, doing odd jobs and working at a cement mill. (His father, with whom he shared a small apartment, in Pasadena, pitched in by doing the cooking.) He graduated in 1930 and was hired by Bell Labs, in New York City, as a research engineer. After a year, he transferred to the company’s patent department, believing the skills he would learn there might be useful to him when he became an inventor.

In his notebooks during the 1930s, Carlson recorded more than 400 ideas for products, among them a raincoat with gutters to channel water away from trouser legs; a toothbrush with replaceable bristles; a see-through toothpaste tube, made of cellophane; a perforated-plastic filter tip for cigarettes. In 1934, he married Elsa von Mallen, who had given him her telephone number after dancing with him to Duke Ellington records at a party at the YWCA. The marriage was troubled almost from the beginning. “I don’t know what to do or say—he’s so much smarter,” she said shortly before they divorced, in 1945. Partly to get out of the house, Carlson enrolled in night classes at New YorkLawSchool in 1936. He did most of his studying at the New York Public Library, where he copied by hand long passages from law books that he couldn’t afford to buy. His copying gave him writer’s cramp and made him think again about the desirability of a device that, unlike carbon paper, could be used to reproduce documents that already existed.

“I recognized quite early that if conventional photography would have worked for an office copier it would have been done before by the big companies in the photographic field who certainly would have explored that possibility pretty thoroughly,” he told Ermenc. “So I deliberately turned away from the conventional photographic processes and started searching in the library for information about all the different ways in which light will affect matter. I soon came upon photoelectricity and photoconductivity.”

Photoelectricity is such a complex phenomenon that it took Albert Einstein to explain it, in 1905; he was awarded the Nobel Prize in 1921 for having done so. (Incidentally, Einstein, like Carlson, was a physicist who worked in a patent office.) A photoconductive material is one whose ability to conduct electricity increases when light shines on it. Carlson reasoned that he might be able to make a copying machine based on photoconductivity if he could find a material that acted as a conductor when it was illuminated and as an insulator when it was not. His plan was to apply a thin layer of the material to an electrically grounded metal plate. Then, in the dark, he would apply a uniform static electric charge to the entire coated surface. Next, he would project an image of a printed page onto the charged surface, thereby causing the charge to drain away to ground from the illuminated areas (the ones corresponding to the reflective white background of the page) while allowing the charge to persist in areas that remained dark (the ones corresponding to the black ink). Finally, he would dust the entire surface with an oppositely charged powdered toner, which would adhere only to the places where charges remained, thereby forming a visible (and reversed) image of the original page. The powder could then be transferred to a sheet of paper and fused to it: a copy.

This idea would become the basis of xerography. Every xerographic office copier and laser printer contains a photo- conductive surface, which is known as the photoreceptor. (In a laser printer, the light that shines on the photoreceptor is a digitally controlled laser beam.) Carlson applied for his first patent on October 18, 1937, and began conducting crude experiments. He had learned from his reading that sulfur had the photoconductive properties he was looking for, so he bought some at a chemical supply store and attempted to liquefy it by heating it over a burner on the stove in the kitchen of his apartment, in Queens. In nearly a year of experimentation, he accomplished little beyond setting his sulfur on fire, filling his apartment building with the smell of rotten eggs and angering his wife.

In 1938, he rented a laboratory and hired an assistant, an unemployed physicist named Otto Kornei, who had recently emigrated from Austria. Carlson’s laboratory was really just the back room of a beauty parlor—it had previously served as a janitor’s closet—but it had running water and a gas connection, and Kornei soon succeeded in applying a thin film of liquefied sulfur to zinc plates the size of business cards.

Working with Carlson one day soon afterward, he wrote the date and place—10.-22.-38 ASTORIA—on a glass microscope slide, turned out the lights and rubbed a sulfur-coated plate with his handkerchief to give it a static electric charge. As Carlson watched, Kornei placed the slide facedown against the plate and turned on a bright flood lamp for several seconds. He turned off the lamp, removed the slide and dusted the plate with powder. “The letters came out clearly,” Carlson wrote later. Carlson pressed a piece of wax paper against the image so that most of the powder stuck to it. He was now holding the world’s first xerographic copy. (That historic copy is in the Smithsonian’s collection.) He gazed at the paper for a long time and held it up to the window. Then he took his assistant to lunch.

Kornei, unlike his boss, was unimpressed, and soon took a job at an electronics company in Cleveland. Carlson continued alone and spent six years unsuccessfully trying to interest companies in developing and manufacturing the machine he had envisioned. In 1944, a chance conversation led him to the Battelle Memorial Institute, a private, nonprofit research-and-development organization in Columbus, Ohio. He performed his standard demonstration for a halfdozen of Battelle’s scientists and engineers, then braced himself for the throat-clearing and paper-rearranging that was the usual response to his presentations. But a Battelle engineer named Russell Dayton held up the scrap of wax paper and said to his colleagues, “However crude this may seem, this is the first time any of you have seen a reproduction made without any chemical reaction and [with] a dry process.” Battelle agreed to invest.

This was significant progress, although it was not the vindication that Carlson had dreamed of. Battelle allocated just $3,000 for xerographic research in 1944, and more than a few of its scientists remained doubtful for years to come. “Of those who knew about it,” Dayton said later, “at least 50 percent thought it was a stupid idea and that Battelle should never have gotten into it. It just goes to prove that if you’ve got something unique, you don’t take a poll.”

Also in 1944, a New York City patent agent and freelance writer named Nicholas Langer came across a copy of one of Carlson’s first patents and wrote a laudatory article about it for Radio News. A condensed version of the article appeared the next year in a technical bulletin published by Eastman Kodak and caught the attention of Joseph C. Wilson, president of the Haloid Company, which, like Kodak, was situated in Rochester, New York. For some time, Wilson had wanted to establish Haloid in a business that, unlike photographic supplies, wasn’t already dominated by its powerful crosstown rival. Following a lengthy negotiation, in 1947 Haloid agreed to pay Battelle $10,000 for a one-year license to help the company build office copiers based on Carlson’s idea, with options to renew. Aquarter of the fee, or $2,500, went to Carlson—the first money he earned from his idea, which was now a decade old.

Success was not immediate. Haloid, with considerable help from Battelle, introduced its first xerographic copier, which it called the Model A, in 1949, but the machine was almost comically difficult to operate, and all the early testers returned it. “Awkward in its lack of co-ordinated design, it required more than a dozen manual operations before it would produce a copy,” Haloid’s research chief wrote in 1971. That was an understatement; four dozen manual operations was more like it. With practice, Haloid promised, a skilled operator could hope to make a copy every three minutes or so. The Model A Copier was so hard to use that it might have sunk xerography, and possibly Haloid itself, if it hadn’t turned out to be good at something else: creating inexpensive paper masters for offset lithographic duplicators, a type of printing press.

Developing a truly useful office copier took another ten years and many millions of dollars. Carlson became a Haloid consultant in 1948. Later, he was given a laboratory and an assistant, and he made a number of discoveries, for which he received three dozen patents. Still, Carlson’s most important contribution to the project during the 1950s was probably helping to maintain the company’s enthusiasm for his idea despite repeated setbacks. ABattelle engineer said later, “There always had to be something extralogical about continuing.”

Haloid’s final push to build an automated xerographic copier—the model 914—began in the early ’50s. The main theoretical work was done by a group of young physicists, who worked not in a gleaming laboratory but in an old house in a seedy part of town. Robert Gundlach, who went to work at Haloid in 1952 and eventually earned 155 xerography-related patents, told me not long ago, “You had to park about a block away and walk. They put Ernie Lehmann and me up in the attic, in a room that had a ceiling that sloped so that you couldn’t stand up except in the middle of the room. There was a group working on powder-cloud development, which involved making a fog of submicron carbon particles. Every once in a while we would have to vent the developing device, because it would become clogged with carbon dust, and we had to learn not to do that on Tuesdays, because that was when the lady next door hung out her white linens.”

The company’s engineers scrounged bolts, springs, aluminum tubing and other items from a junkyard. An early prototype was eventually able to make copies—though only in the dark, since it had no exterior cabinet to prevent the room’s lights from discharging the photoreceptor and spoiling the images—but it looked more like a science fair project than an office machine.

A photoreceptor has to be cleaned between exposures. In the Model A—in which the photoreceptor was a flat plate coated with selenium, a far more sensitive photoconductor than sulfur—the cleaning was done manually, by rocking the plate in a tray filled with what was essentially cat litter. (Coffee grounds, soybean meal, flax seed and corn meal were also tried and rejected—they attracted vermin.) In a 914, the photoreceptor was a cylinder and the cleaning was done by a rotating fur brush.

That Haloid thought of using fur may have had more to do with chance than with science: some of the company’s researchers and engineers in those days worked in a bleak, tenement-like brick building on Lake Avenue whose ground-floor storefront was occupied by the Crosby Frisian Fur Co. The engineers tried and rejected beaver and raccoon, then determined that the back fur of New Zealand rabbits worked just about right. The brushes were handsewn by the father of the fur shop’s owner. The engineers trimmed them to size on a homemade machine that looked a little like a reel lawn mower.

In the winter of 1959, the company rented a grim warehouse on Lyell Avenue and built a few final 914 prototypes there. The building’s owner, to save money, turned the furnace down at five o’clock, so the engineers erected a canvas enclosure around each machine to contain the heat given off by the machine itself and worked inside, often around the clock. They and other Haloid employees were trying to identify and eliminate the 914’s remaining defects, of which there were depressingly many.

One of the biggest challenges had to do with the toner— the powdered resin that’s used to develop xerographic images. A toner has to have many seemingly mutually exclusive characteristics. It has to melt quickly and completely, but can’t be so soft that it smears on the photoreceptor or so hard that it damages the surface; it has to be brittle enough to be capable of being ground to a fine powder to yield sharp, high-resolution images, but not so fine that it fouls the machine. And so on. “The problems are self-exacerbating once they begin,” Gundlach told me. An ideal toner, the scientists realized, would have some of the same properties as ice, whose viscosity, as you warm it, doesn’t change until the moment it turns into a liquid. Most thermoplastic resins, in contrast, pass through a gradient of states between solid and liquid, as chocolate does. No one knew whether a suitable resin existed.

A satisfactory toner was developed virtually at the last minute, primarily through the efforts of a Haloid chemist named Michael Insalaco, and the first production 914 shipped in March 1960. The customer was Standard Press Steel, a manufacturer of metal fasteners in Jenkintown, Pennsylvania. The machine weighed nearly 650 pounds and had to be delivered on a tilting dolly so that it could be angled through doors.

In the mid-1950s, Carlson had worried that few businesses might ever need to make as many as a hundred copies a day—the threshold, he felt, at which xerographic office copying would be economical. During the 914’s development, Haloid’s engineering department had speculated that very heavy users, at peak periods, might make five times that many copies in a day, or 10,000 a month. From the day the first 914 arrived in Jenkintown, though, Standard Press employees used it to make copies at several times the predicted maximum rate. Using a 914 was seductively easy, since there were no special papers or chemical developers, and all you had to do was push a button—and the copy itself provided positive reinforcement, because it didn’t smell bad, curl up or turn brown. The numbers seemed inconceivable at first, but the first companies to receive 914s were turning out 2,000 to 3,000 copies a day.

Truly epochal technology shifts are sometimes incomprehensible until after they’ve occurred. When the first videocassette recorders were introduced, in the 1970s, the Motion Picture Association of America spent millions complaining to Congress that Hollywood was about to be annihilated. Instead, the VCR revived Hollywood by generating billions in rental fees and transforming the way movies were financed. Xerox machines had a similarly sweeping impact. Office workers didn’t realize how much they needed copies until, in 1960, they were suddenly able to make them easily. The technology itself created the demand that ultimately sustained it. Invention was the mother of necessity.

Chester carlson began earning royalties from xerography in 1947. The payments were small at first. In 1953, he traded his old Studebaker for a new one. The next year, he and his second wife, Dorris, whom he had married in 1946, built an unpretentious three-bedroom house just outside Rochester. Carlson eventually earned something like $200 million from his invention, but he lived in that house for the rest of his life. He sometimes told Dorris that he could be just as happy, or perhaps happier, living in a trailer in the yard. “I think he felt guilty about having a nice, comfortable house,” she said later, “and when people would come in and say, ‘Oh, this is lovely,’ he would say, ‘Dorris planned it all.’ ” She was never certain how truly serious he was about his trailer, but he mentioned it frequently, and she would tease him when he did: “And will you take your 13 steel filing cabinets with you?”

Carlson came to terms with his wealth by divesting himself of most of it. His philanthropy during the final decade of his life was prodigious. It was also entirely anonymous. When he gave the money to build a building, he did not permit his name to be revealed publicly, never mind be engraved in stone above the door. In the mid-1960s, for example, he gave money to Cal Tech for a center for the study of chemical physics, his field of concentration, but stipulated that the building be named for Arthur Amos Noyes, the professor whose teaching had influenced him the most. Carlson made large contributions to organizations that promoted world peace. He supported civil rights organizations. He bought apartment buildings in Washington, D.C. and New York City and arranged for the buildings to be racially integrated. He gave millions to the United Negro College Fund and made contributions to individual black colleges. He (and his will) provided most of the funding during the ’60s and ’70s for Robert Maynard Hutchins’ Center for the Study of Democratic Institutions. He supported the Fellowship of Reconciliation and other pacifist organizations. He gave money to schools, libraries and international relief agencies. The list of his beneficiaries was long, and he himself weighed every request. (His philanthropy continues today, through the Chester and Dorris Carlson Charitable Trust.)

Carlson died, of a heart attack, on September 19, 1968. He was 62. U Thant, the secretary-general of the United Nations, who had been a friend of Carlson’s, wrote at the time, “To know Chester Carlson was to like him, to love him and to respect him. He was generally known as the inventor of xerography, and although it was an extraordinary achievement in the technological and scientific field, I respected him more as a man of exceptional moral stature and as a humanist. His concern for the future of the human situation was genuine, and his dedication to the principles of the United Nations was profound. He belonged to that rare breed of leaders who generate in our hearts faith in man and hope for the future.”

In the nearly seven decades since Chester Carlson thought of xerography, no one has come up with a better way of making copies on plain paper. That is an almost inconceivable achievement, given the usual pace of hightechnology innovation, evolution and extinction. The number of copies made all over the world on xerographic machines has increased every year since Carlson and Kornei peeled away that first scrap of wax paper in Astoria back in 1938. In 1955, four years before the introduction of the 914, the world made about 20 million copies, almost all of them by non-xerographic means; in 1964, five years after the introduction of the 914, it made nine and a half billion, almost all xerographically. Five hundred and fifty billion in 1984. Seven hundred billion in 1985. This year, trillions.

And Carlson’s invention is still evolving. One of the most advanced machines today is the Xerox DocuColor iGen3, introduced in 2001. It is a digital printing system rather than a copier but operates xerographically. It produces 6,000 fullcolor, 8-1/2- by 11-inch offset-quality impressions per hour, and those impressions can be customized on the fly. Its four “imaging stations” lay down cyan, magenta, yellow and black toners on an electrostatically charged photoconductive belt, from which the powders are transferred, all at once, onto paper. The underlying imaging technology, by which a monochromatic process makes full-color prints, is hard to explain, but essentially it involves separating a polychromatic image into the three complementary colors (plus black) in order to “enable one color to be recorded, and then developing with colored powder to produce a copy of that color, then repeating for each other color and superimposing the dust images on the same copy sheet.”

That, at any rate, is how Chester Carlson described it in his second xerography patent, which he filed on April 4, 1939.