Menlo Park (1876–1881)

Edison's major innovation was the first industrial research lab, which was built in Menlo Park, New Jersey. It was built with the funds from the sale of Edison's quadruplex telegraph. After his demonstration of the telegraph, Edison was not sure that his original plan to sell it for $4,000 to $5,000 was right, so he asked Western Union to make a bid. He was surprised to hear them offer $10,000,^{[citation needed]} which he gratefully accepted. The quadruplex telegraph was Edison's first big financial success, and Menlo Park became the first institution set up with the specific purpose of producing constant technological innovation and improvement. Edison was legally attributed with most of the inventions produced there, though many employees carried out research and development under his direction. His staff was generally told to carry out his directions in conducting research, and he drove them hard to produce results.

Edison's Menlo Park Laboratory, removed to Greenfield Village at Henry Ford Museum in Dearborn, Michigan. (Note the organ against the back wall)

William J. Hammer, a consulting electrical engineer, began his duties as a laboratory assistant to Edison in December 1879. He assisted in experiments on the telephone, phonograph, electric railway, iron ore separator, electric lighting, and other developing inventions. However, Hammer worked primarily on the incandescent electric lamp and was put in charge of tests and records on that device. In 1880, he was appointed chief engineer of the Edison Lamp Works. In his first year, the plant under General Manager Francis Robbins Upton turned out 50,000 lamps. According to Edison, Hammer was "a pioneer of incandescent electric lighting".

Thomas Edison's first successful light bulb model, used in public demonstration at Menlo Park, December 1879

Nearly all of Edison's patents were utility patents, which were protected for a 17-year period and included inventions or processes that are electrical, mechanical, or chemical in nature. About a dozen were design patents, which protect an ornamental design for up to a 14-year period. As in most patents, the inventions he described were improvements over prior art. The phonograph patent, in contrast, was unprecedented as describing the first device to record and reproduce sounds.^[24] Edison did not invent the first electric light bulb, but instead invented the first commercially practical incandescent light. Many earlier inventors had previously devised incandescent lamps including Henry Woodward, and Mathew Evans. Others who developed early and not commercially practical incandescent electric lamps included Humphry Davy, James Bowman Lindsay, Moses G. Farmer,^[25] William E. Sawyer, Joseph Swan and Heinrich Göbel. Some of these early bulbs had such flaws as an extremely short life, high expense to produce, and high electric current drawn, making them difficult to apply on a large scale commercially. In 1878, Edison applied the term filament to the element of glowing wire carrying the current, although the English inventor Joseph Swan had used the term prior to this. Swan developed an incandescent light with a long lasting filament at about the same time as Edison, but it lacked the high resistance needed to be an effective part of an electrical utility. Edison and his co-workers set about the task of creating longer-lasting bulbs. In Britain, Joseph Swan had been able to obtain a patent on the incandescent lamp because of an oversight in the drafting of Edison's patent application.^[26] Unable to raise the required capital in Britain because of this, Edison was forced to enter into a joint venture with Swan (known as Ediswan). Swan acknowledged that Edison had anticipated him, saying "Edison is entitled to more than I ... he has seen further into this subject, vastly than I, and foreseen and provided for details that I did not comprehend until I saw his system".^[27] By 1879, Edison had produced a new concept: a high resistance lamp in a very high vacuum, which would burn for hundreds of hours. While the earlier inventors had produced electric lighting in laboratory conditions, dating back to a demonstration of a glowing wire by Alessandro Volta in 1800, Edison concentrated on commercial application, and was able to sell the concept to homes and businesses by mass-producing relatively long-lasting light bulbs and creating a complete system for the generation and distribution of electricity.
In just over a decade Edison's Menlo Park laboratory had expanded to occupy two city blocks. Edison said he wanted the lab to have "a stock of almost every conceivable material". A newspaper article printed in 1887 reveals the seriousness of his claim, stating the lab contained "eight thousand kinds of chemicals, every kind of screw made, every size of needle, every kind of cord or wire, hair of humans, horses, hogs, cows, rabbits, goats, minx, camels ... silk in every texture, cocoons, various kinds of hoofs, shark's teeth, deer horns, tortoise shell ... cork, resin, varnish and oil, ostrich feathers, a peacock's tail, jet, amber, rubber, all ores ..." and the list goes on.^[28]
Over his desk, Edison displayed a placard with Sir Joshua Reynolds' famous quote: "There is no expedient to which a man will not resort to avoid the real labor of thinking."^[29] This slogan was reputedly posted at several other locations throughout the facility.
With Menlo Park, Edison had created the first industrial laboratory concerned with creating knowledge and then controlling its application.