In the public mind Edison remains not an inventor so much as an archetype. Self-made — with only three months of formal schooling — he is a living, breathing example of American know-how. In countless school-age biographies, Enterprising Edison peddles papers on a train, then prints his own newspaper from the baggage car. Eccentric Edison sleeps fully clothed on his laboratory floor. Eureka Edison tries hundreds of filaments for his electric light before settling on carbonized cotton thread, which emits a brilliant and lasting glow. These are accurate, if exaggerated, pieces of this puzzling genius. Yet the puzzle can be completed only by Entrepreneurial Edison, whose greatest creation was the inventor as master of mass production and marketing.
In late 1875, Edison decided to leave Newark and build a new laboratory on two tracts of cheap land in central New Jersey. The place was Menlo Park. That winter, as the electric pen found willing buyers, Edison's father supervised the construction of this first research and development lab, with space for a growing cadre of engineers, a place for prototypes to be picked apart for useful pieces, a pipe organ so employees could gather to sing during rare breaks, and shelves stocked with 2,500 bottles of chemicals. In January 1876, Mary gave birth to Thomas Edison, Jr. The inventor quickly nicknamed his son "Dash" to complement daughter Marion, whom Edison called "Dot."
With its patent pending, the "Electric Pen and Duplicating Press" went on display in 1876 at the United States Centennial Exhibition in Philadelphia. By the end of that year, Edison began selling the rights to manufacture and market the pen. One of the eventual buyers was the A.B. Dick Company of Chicago, which turned the print process into the first mimeograph. Within a few years, electric pens were punching out stencils in offices from Washington, D.C. to China. Then, like so many useful inventions before it, the pen was ultimately replaced by a better stencil maker, the typewriter. Edison's elegant little pen was obsolete.
But Edison now was dreaming of a machine that would reproduce human speech. Only a year after licensing the pen, Edison produced the phonograph and became world famous. Two years after, he gave the world light. By 1881, the same Menlo Park factory that had churned out electric pens had been retooled and was making hundreds of electric lightbulbs per day.
Edison kept a prototype of the pen on display in the Menlo Park lab. In 1876 the electric pen system had won a bronze medal at the Centennial Exhibition. As Edison's partner Charles Batchelor told it, the medal was presented to Edison in his New York office one afternoon. Batchelor and Edison then headed home to Menlo Park. Lost in talk about some new experiments, they left the medal on the ferryboat. Batchelor wanted to go back for it, but Edison said, "Don't bother, someone will surely have picked it up." He never mentioned the medal to Batchelor again, his mind already intent on the next wondrous invention.