Thomas Alva Edison (February 11, 1847 – October 18, 1931) was an American inventor and businessman. He created many devices in areas such as electric power generation, sound recording, and motion pictures. These inventions, including the phonograph, the motion picture camera, and early electric light bulbs, have greatly influenced the modern world. He was one of the first inventors to use organized science and teamwork in the invention process, working with many researchers and employees. He built the first industrial research laboratory.

Edison grew up in the American Midwest. Early in his career, he worked as a telegraph operator, which led to some of his earliest inventions. In 1876, he opened his first laboratory in Menlo Park, New Jersey, where many of his early inventions were made. He started a business and became wealthy. Edison used his money to support his work as an inventor. This included projects such as experimental mining operations, the first film studio, and 1,093 U.S. patents.

Early life

Thomas Edison was born in 1847 in Milan, Ohio, but moved to Port Huron, Michigan, in 1854 when his family relocated there. He was the seventh and final child of Samuel Ogden Edison Jr. (1804–1896, born in Marshalltown, Nova Scotia) and Nancy Matthews Elliott (1810–1871, born in Chenango County, New York). His family line from his father’s side was Dutch, tracing back to New Jersey.

Edison’s great-grandfather, John Edeson, was a loyalist who fled New Jersey for Nova Scotia in 1784. The family later moved to Middlesex County, Upper Canada, around 1811. His grandfather, Capt. Samuel Edison Sr., served in the 1st Middlesex Militia during the War of 1812. Edison’s father, Samuel Edison Jr., lived in Vienna, Ontario, but later moved to Ohio after being involved in the Rebellion of 1837.

Edison’s mother, a former school teacher, taught him reading, writing, and arithmetic. He attended school for only a few months but was very curious and often learned by reading on his own. A book called A School Compendium of Natural and Experimental Philosophy, given to him by his mother, inspired his interest in electricity. His parents also owned books by Thomas Paine, which influenced Edison’s thinking throughout his life.

At age 12, Edison began experiencing hearing problems. Historian Paul Israel believed his deafness was caused by scarlet fever during childhood and untreated middle-ear infections. He later made up stories about the cause of his hearing loss. He became completely deaf in one ear and could barely hear in the other. As an adult, he listened to music or piano by clamping his teeth into wood to feel sound waves through his skull. He believed his hearing loss helped him focus better on his work.

Edison started his career as a news butcher, selling newspapers, candy, and vegetables on trains between Port Huron and Detroit. By age 13, he earned $50 a week, most of which he used to buy equipment for electrical and chemical experiments. He founded the Grand Trunk Herald, a newspaper he sold with other papers. The newspaper published 24 issues and was known for its local news coverage. Five hundred people subscribed to it, and Edison hired at least two assistants. He kept a frame with the first issue of the Grand Trunk Herald in his home until his death.

At age 15, in 1862, Edison saved a child from a runaway train. The child’s father was so grateful that he trained Edison to become a telegraph operator. Edison worked as a telegrapher in a local general store before moving to Stratford Junction, Ontario, where he worked as a night telegrapher for the Grand Trunk Railway. During his job, he studied chemical experiments and qualitative analysis, but he often fell asleep. This led to a near train collision, after which he resigned from his position.

Telegraphy

From 1863 to 1869, Edison held night shift telegraph jobs in Ontario, Michigan, Kentucky, Ohio, and Massachusetts. While working for Western Union, he operated the Associated Press bureau news wire. In Cincinnati, he lived with Ezra Gilliland, a friend he kept for 25 years. He joined the National Telegraph Union and contributed articles to their magazine. In his free time, Edison experimented with inventions and studied Spanish. He was known among young telegraph operators for his intelligence and willingness to try new ideas, though his experiments sometimes disrupted his work.

In Boston, from 1867 to 1869, Edison earned money by inventing a stock ticker for local customers. However, he lost this income when he attempted to expand the project to New York without approval. His first patent, U.S. patent 90,646 for the electric vote recorder, was granted on June 1, 1869.

In 1869, Edison moved to New York City. A mentor during this time was Franklin Leonard Pope, a fellow telegrapher who let the struggling Edison live and work in his home in Elizabeth, New Jersey, while Edison worked for Samuel Laws at the Gold Indicator Company. Pope and Edison started their own company in October 1869, working as electrical engineers. Edison attracted wealthy investors, who helped fund the business. With the money, they hired 50 employees and opened a larger workshop in Newark, New Jersey. The company earned income by renting telegraph lines and producing machines to record telegraphs and typewriters that printed directly onto wires. Edison closely managed his employees’ work and conducted many experiments.

Edison enrolled in a chemistry course at The Cooper Union for the Advancement of Science and Art to support his work on a new telegraph system with Charles Batchelor. This was his only formal education at a higher learning institution. At the factory, Edison and Batchelor worked closely together; their shared notebooks, signed "E&B," show continuous efforts to improve the telegraph.

Edison expanded his company to include hundreds of employees. In 1874, he received $30,000 ($853,676 in 2025) for inventing the first telegraph capable of sending four messages simultaneously through one wire. He used the money to invest in the Port Huron street railway, owned by his brother William Pitt. He also grew his business and hired his young nephew and father.

Menlo Park laboratory

In Menlo Park, New Jersey, Edison created the first industrial laboratory focused on creating knowledge and controlling its use. The laboratory was built in 1876 in Raritan Township, which later became Edison Township in his honor. Funds from the sale of Edison's quadruplex telegraph supported its construction. His staff followed his instructions closely during research, and he pushed them hard to achieve results. Edison's name appears on 1,093 patents. As the leader of the laboratory, he was credited for many inventions made by his team. He worked extremely long hours and expected others to do the same. This often meant 18 hours daily from Monday to Friday, plus additional work on weekends. One employee described the work as "the limits of human exhaustion." Edison often fought legal battles and hired patent lawyers. At times, this allowed him to challenge the intellectual property rights of others.

For Edison, large business opportunities brought public attention. He limited access to the Menlo Park laboratory and carefully managed his public image through interviews. He expanded his involvement in public affairs by funding the creation of Science, a journal that published its first volume in 1880. Edison remained anonymous in his role, and the journal initially promoted pro-Edison articles. He stopped publishing the journal in 1883 because it was not profitable. Alexander Graham Bell later took over its leadership.

Within a little over 10 years, Edison's Menlo Park laboratory grew to cover two city blocks. Edison wanted the lab to have "a stock of almost every conceivable material." In 1887, the lab contained "eight thousand kinds of chemicals, every kind of screw, every size of needle, every type of cord or wire, hair from 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, oil, ostrich feathers, a peacock's tail, jet, amber, rubber, all ores," and the list continued.

In 1876, Edison began improving the microphone for telephones by developing a carbon microphone. This device used two metal plates separated by carbon granules that changed resistance based on sound wave pressure.

In 1877, Edison and his supporters at Western Union aimed to compete with Alexander Graham Bell on telephone technology. Edison believed the weakest part of Bell's telephone was the microphone designed by Emile Berliner. He tested many designs to find the best sound quality for his deaf ears. His main idea was to use a stronger current that varied with sound waves. Sound waves changed the current by pressing a carbon pad, which altered the circuit's resistance. After testing 150 materials, Edison found that parchment and tinfoil were best for the diaphragm, while specially coated rubber worked as the semiconductor.

In 1878, David Edward Hughes published a paper on the physics of loose-contact carbon microphones. He claimed to have discovered the semiconductor effect and introduced the Hughes Telephone. This angered Edison and caused public controversy, especially because Hughes acknowledged advice from one of Edison's colleagues.

The invention that first brought Edison widespread attention was the phonograph in 1877. He promoted the device by working with journalists and giving public demonstrations. The public found the phonograph surprising and almost magical. Edison became known as "The Wizard of Menlo Park." As he aged, he disliked being called a genius and emphasized "one percent inspiration and 99 percent perspiration."

His first phonograph used tinfoil wrapped around a grooved cylinder. Though the sound quality was limited and recordings could only be played a few times, the phonograph made Edison a celebrity. Joseph Henry, president of the National Academy of Sciences and a leading electrical scientist in the U.S., called Edison "the most ingenious inventor in this country or any other." In April 1878, Edison demonstrated the phonograph before the National Academy of Sciences. Though he obtained a patent for the phonograph in 1878, he did little to develop it until Alexander Graham Bell, Chichester Bell, and Charles Tainter created a similar device in the 1880s using wax-coated cardboard cylinders.

In 1887, the Edison Phonograph Company was formed to compete with Bell. Gilliland, who had worked for Bell on the phonograph, helped Edison start the new company. However, the venture ran out of money before producing a product. Jesse Lippincott offered deals to Edison, Gilliland, and Bell to create a phonograph monopoly. Knowing Edison would refuse, Lippincott hid his and others' roles in the deal and sent the offer through Edison's personal attorney. When Edison discovered the scheme, he was angry, and Gilliland left for Europe, ending their friendship. After five years of legal battles, Edison gained full control of the company. The conflict caused other disagreements among Edison's wealthy inventor-friends.

Edison struggled for years to bring a phonograph to market. The main technical problem was finding a recording material durable enough for repeated use without damaging the phonograph's needle. He tried making talking dolls with a miniature phonograph inside, but the system often failed during shipping, and production stopped in 1890. Edison believed the phonograph could revolutionize business and change the role of secretaries. However, by 1899, Edison's phonograph company adapted to market demands and produced a cheap model popular for entertainment. In 1900, the phonograph sold for $10, and buyers could choose from 3,000 different musical records made by Edison's 1,000 employees. Experts supervised the quality of the recordings. Edison had no musical training, could not read sheet music, and was mostly deaf. Until 1915, he personally approved every artist based on what he thought sounded good and kept their names from appearing on the music.

The rise of radio hurt phonograph sales. Edison's business sold 90% fewer records in 1921 compared to 1920. From 1922 to 1926, radio sales increased by 843%. Younger managers, including his son Charles, tried to convince Edison to enter the radio industry or use new advertising methods. Instead, Edison focused on removing employees who did not meet his standards.

Edison invented a highly sensitive device called the tasimeter, which measured infrared radiation. He created it to measure the heat from the solar corona during the total solar eclipse of July 29, 1878.

Electric light

In 1878, Edison started working on a system for electrical lighting that he could use in a large-scale commercial utility. He wanted this system to compete with gas and oil lighting. A key part of his system was creating a strong, low-resistance light bulb, which was needed for a wide-scale indoor lighting system. Many inventors had made light bulbs before Edison, but these early bulbs had problems, such as short lifespans and needing high electric current, which made them hard to use on a large scale. Edison first tried using a cardboard filament covered in lampblack. This burned out too quickly. He then tested different materials, like grasses and canes, before choosing bamboo as the best filament.

Edison focused on solving lighting as a complete system. This required experiments, market research with Grosvenor Lowrey, connecting with investors, viewing electric generators, planning power distribution, and making public statements to promote his work. He formed the Edison Electric Light Company in New York City with financiers like J. P. Morgan, Spencer Trask, and members of the Vanderbilt family.

Edison kept improving his design. On November 4, 1879, he filed a patent for an electric lamp using a carbon filament coiled and connected to platinum wires. The patent described ways to make the carbon filament, such as using cotton thread, wood splints, or paper. Later, Edison and Batchleor discovered that a carbonized bamboo filament could last over 1,200 hours. This led Edison to choose the 110V power standard used in the United States. This was a higher voltage than what competitors used. Many employees helped test filaments, make glass bulbs, and create vacuums for the filaments to glow. By February 1880, people visited Menlo Park to see the "Village of Light."

Edison worked to prevent the bulb from blackening due to carbon emissions from the hot filament. This led to the creation of Edison effect bulbs. His 1883 patent for voltage regulation was the first U.S. patent for an electronic device because it used the Edison effect in an active component. The Edison Effect was important for later vacuum tube designs.

In 1878, Edison hired Francis Robbins Upton, a former student of Hermann von Helmholtz. Upton received 5% of company profits and later became general manager after leading research on electric lighting. He helped write Edison's speeches and with hiring. John Ott worked for Edison, making mechanical improvements and conducting experiments. Both men gave Edison credit for most patents, but Ott was credited for some of his own work. Ott's testimony supported Edison's patent claims. John Ott's brother, Fred, worked for Edison for 57 years as an experimental assistant.

Henry Villard, president of the Oregon Railroad and Navigation Company, saw Edison's 1879 demonstration. He asked Edison to install his lighting system on the Columbia ship. Edison agreed, and most of the work was completed by May 1880. The Columbia traveled to New York, where Edison's team installed the new lighting system. This was Edison's first commercial use of his incandescent bulb. The system was removed from the Columbia in 1895.

Villard later helped fund a train powered by Edison's technology. The train worked, and some designs were patented, but Edison focused on bulbs and did not continue developing the train.

Edison's incandescent bulb gained popularity in Europe. He sent engineers to promote the system in London and other European cities.

On September 4, 1882, Edison turned on the electrical lighting system for his 946 customers in Manhattan. Many people did not notice the change because the lights were steady and similar to gas lighting. The Boston Globe reported on this event.

In 1883, the U.S. patent office ruled that Edison's filament improvement process was based on Sawyer's method and was invalid. Edison's company changed their process until 1889, when a judge ruled their new patent was valid. To avoid a court battle with Joseph Swan, who had a British patent, Edison and Swan formed a joint company called Ediswan to market the invention in Britain. Westinghouse, which owned Sawyer's patent, took a large share of the bulb market by 1889.

After creating a commercially viable light bulb on October 21, 1879, Edison developed an electric utility to compete with gas lighting. To show progress, he hosted a meeting illuminated by his system. On December 17, 1880, he founded the Edison Illuminating Company. During the 1880s, he patented a system for distributing electricity.

The amount of copper wire needed for this technology was very large. To reduce copper use, Edison invented a three-prong wire system.

To expand in New York, Edison's company opened a second office on 65th Avenue. The Edison Machine Works and Edison Electric Tube Company opened in New York by year's end. Edison paid his workers more than other companies in the 1880s. Before commercializing power distribution, Edison needed a way to measure customer power use. He invented a device using zinc solution and plates that collected current. The zinc on the plates was weighed monthly to calculate usage and bill customers.

In January 1882, Edison turned on the first steam-generating power station in London, producing 93 kW. On September 4, 1882, he activated a 600 kW power station in New York City, providing 110 volts direct current (DC). Customer subscriptions grew to 508 with 10,164 lamps.

As Edison expanded his DC system, he faced competition from companies using alternating current (AC). AC systems for street lighting had grown in the U.S. by the 1880s. Transformers developed in Europe and by Westinghouse Electric in the U.S. allowed AC to be transmitted over long distances using thinner, cheaper wires. This made AC suitable for street lighting and small business use.

Mining

Starting in the late 1870s, Edison became interested in mining. High-quality iron ore was not enough on the East Coast, so people had to ship it from the Midwest, which was expensive. Edison tried to solve this by mining lower quality ore and beach sand. Others had tried using magnets to separate iron from other metals, but none had done it successfully or made money.

In 1880, the Edison Ore Milling Company began by separating iron from beach sand. Edison promised to deliver hundreds of tons of ore each month to customers, but after three years, the operation closed, and only one customer received their ore. William Kennedy Dickson and John Birkinbine led the project. Batchelor and Insull provided some money, but Edison used most of the funds from his own savings.

Although the first mining project failed, Edison was able to license some of the technology to other iron producers. The West Orange team continued improving the technology, and Edison bought a mine in Bechtelsville, Pennsylvania. Birkinbine wanted to use the mine to show others how the technology worked, but Edison wanted to control the mining industry himself. Birkinbine was fired in 1890.

Edison bought several mines in the eastern United States and built a new central mining operation in Ogdensburg, New Jersey. The new process used rollers and crushers to break apart large rocks. To get the rocks, Edison bought the largest steam shovel in America. One part of Edison’s system used electric rollers that moved very fast, rotating 3,500 feet per minute. The rollers’ gears released when rocks were dropped in, using their movement to crush the rocks. Edison focused on automation instead of manual labor, using conveyor belts, gravity, and sieves to move and separate ore. Fine particles were sent through a system of 480 electromagnets to select iron.

Customers avoided iron with high phosphorus levels because it ruined the Bessemer process. Edison’s system used an air-powered method to remove phosphorus by taking advantage of its lower weight. Economic reasons required iron ore to be mixed into briquettes for transport to steel mills. Edison automated this process, which he was proud of because it took only two hours. The goal was to have no humans handle the iron. However, the mine lost money quickly.

In 1893, the United States faced a severe recession. High costs from mining, falling iron prices, and the expensive lifestyle of Edison’s wife and children put him at risk of being unable to pay his debts. He also had health problems from diabetes and took a loan from his father-in-law.

In 1901, Edison visited an industrial exhibition in Ontario, Canada, and saw nickel and cobalt deposits that could help his electrical equipment production. He returned as a mining prospector and is credited with discovering the Falconbridge ore body. His attempts to mine the ore failed, and he gave up his claim in 1903.

Despite the mining company’s failure, Edison used materials and equipment from the iron mining process to make Portland cement. Manufacturing iron ore created a lot of waste sand, which he sold to cement makers. In 1899, he started the Edison Portland Cement Company to produce and improve cement.

Making Portland cement requires baking limestone and other minerals at high temperatures. Edison designed a new system that used horizontal 150-foot-long kilns, allowing the cement to reach the same quality by cooking longer at a lower temperature. This used less coal and reduced the need for manual labor. Edison reused materials from the Ogden mine to build his system. He later sold his cement-making process to other manufacturers and collected money from them until the 1920s.

Running machines in the dusty environment of a mining operation caused problems, especially for dynamos, which needed cooling but could not be sealed. Edison invented a fan cooling system to bring in fresh air to cool the dynamos while keeping dust out.

In 1901, Edison tried to use his cement business to create affordable housing. He planned to build small towns where people could buy homes. He designed a system to cast entire three-story houses from cement in one mold. He used this method to build homes for workers and promoted it publicly, but it did not generate enough interest to continue.

West Orange

In the spring of 1886, the first labor strike against Thomas Edison took place. It was led by D.J. O'Dare of the Edison Tube Works. At that time, manufacturing jobs in New York City usually lasted nine hours a day, and Edison’s workers were among the highest-paid in the city. However, they did not receive extra pay for working additional hours. The strike aimed to demand higher wages, overtime pay, and the right to form a union. Edison and other managers refused to consider unionization because they feared losing control over their workers. By the end of the year, many manufacturing facilities in New York City closed, and Edison United Manufacturing Company opened a new factory in Schenectady, New York. Citizens of Schenectady helped pay 16% of the cost for the new factory’s real estate to attract Edison’s business to their town.

Samuel Insull began working for Edison in 1881 as a secretary. He had previously worked at Vanity Fair. Insull became a trusted assistant to Edison and helped the family make arrangements when Mary, Edison’s wife, was dying. Insull worked hard, as did all of Edison’s employees. When Edison United Manufacturing Company opened, Insull was one of two managers.

In December 1886, Edison was unable to leave his home because of pleurisy. He recovered but needed emergency surgery in May 1887 to treat abscesses near his ear. He had more surgeries for the same issue in 1906 and 1908.

By 1887, Edison felt he needed more space for his work. He assigned Batchelor to build a new laboratory complex in West Orange, New Jersey. The completed lab was more than ten times larger than his old laboratory in Menlo Park.

In December 1914, a fire at Edison’s factory killed one employee and destroyed thirteen buildings, causing $1.5 million in damage. The phonograph manufacturing area was destroyed. Edison remained optimistic and ordered the factory rebuilt with modern technology. By January, production had resumed. The fire’s impact was less severe because the factory practiced regular fire drills.

In 1921, after President Warren G. Harding was inaugurated, the United States entered a recession. Edison had experience managing businesses during tough economic times and had seen friends go bankrupt. He fired thousands of employees, including executives. By the fall, the economy improved, and business returned. However, Edison’s company narrowly avoided bankruptcy.

In 1896, Edison learned about X-rays after physicist Wilhelm Röntgen discovered them. He received a photo showing Röntgen’s hands with visible bones. Edison was excited by the technology and tried to develop a better X-ray system using stronger glass and more electricity. During experiments, he discovered that X-ray images appear clearer on calcium tungstate screens. He shared this finding with Lord Kelvin.

Edison’s fluoroscope design is still used today, but he stopped the project after nearly losing his eyesight and seriously injuring his assistants, Clarence Dally and Charles Dally. In 1903, Edison said, “Don’t talk to me about X-rays. I am afraid of them.” The brothers often tested the fluoroscopy system on themselves. Clarence Dally died at age 39 from injuries linked to X-ray exposure, including mediastinal cancer.

In the late 1890s, Edison worked on creating a lighter, more efficient rechargeable battery. He aimed to power phonographs but later focused on batteries for electric cars. At the time, lead-acid batteries were common but inefficient and protected by patents. In 1900, Edison decided to develop an alkaline battery for electric cars. His lab tested 10,000 combinations of materials before settling on a nickel-iron design.

Waldemar Jungner worked on a similar battery design, and Edison likely knew about it. Edison and Jungner had a legal dispute over patents as Edison tried to commercialize his battery. Edison received U.S. and European patents for his nickel-iron battery in 1901 and founded the Edison Storage Battery Company. In 1904, Edison worried about losing the patent battle and asked President Theodore Roosevelt to intervene. Roosevelt agreed, but the patent office still denied Edison’s claim.

By 1904, Edison Storage Battery Company employed 450 workers. The first batteries produced were for electric cars. A recall was issued because the batteries lost power after repeated charging.

Henry Ford first met Edison in 1896 while working for Edison Illuminating Company. Edison supported Ford’s early experiments with cars, and Ford left in 1899 to start his own car company. By 1908, gas-powered cars like Ford’s Model T dominated the market. Edison did not produce a mature battery until 1910, when he created a durable nickel-iron battery using lye as the electrolyte. However, the battery was not successful because electric cars were declining, and lead-acid batteries became standard for gas-powered cars. Ford still supported Edison and lent him $1.1 million (equivalent to $35.4 million in 2025) to continue battery research. Edison could not create a battery that was widely accepted.

Motion pictures

In 1888, Thomas Edison and William Kennedy Laurie Dickson, a photographer who worked for Edison, began trying to create a camera that could "do for the eye what the phonograph does for the ear." Their early work involved making tiny photographs on a cylinder. Edison focused on parts that used electricity and machines, while Dickson worked on the parts related to light and film. In 1897, Edison was given a patent for a motion picture camera called the "Kinetograph." Much of the credit for this invention goes to Dickson.

A prototype film camera was built using 19mm film with round images. The first successful tests with this camera were shown publicly on May 20, 1891, in a simple viewer.

Edison was interested in more than just a motion picture camera. He wanted a device called a "kinetophonograph" that could record both moving pictures and sound, playing them back together. In 1890, Dickson tried making a film with sound featuring himself. However, keeping the sound and video in sync was very difficult, and Edison stopped developing this technology for commercial use.

In 1891, Edison built a Kinetoscope, also called a peep-hole viewer. This device was placed in penny arcades, where people could watch short films. The Kinetograph and Kinetoscope were first shown publicly on May 20, 1891.

In the last three months of 1894, an Edison associate sold hundreds of Kinetoscopes in the Netherlands and Italy. In Germany and Austria-Hungary, the Kinetoscope was introduced by a company called the Deutsche-österreichische-Edison-Kinetoscop Gesellschaft, founded by Ludwig Stollwerck of the Schokoladen-Süsswarenfabrik Stollwerck & Co in Cologne.

By 1895, Dickson began setting up his own business separately from Edison. The exact reason for this split is unknown, but it likely involved disagreements between them.

The first Kinetoscopes arrived in Belgium at fairs in early 1895. A company called Edison's Kinétoscope Français was founded in Brussels on January 15, 1895, with the right to sell Kinetoscopes in Monaco, France, and French colonies. The main investors were Belgian industrialists. On May 14, 1895, another company, Edison's Kinétoscope Belge, was founded in Brussels. A businessman named Ladislas-Victor Lewitzki, who lived in London but worked in Belgium and France, started this business. He had connections with Leon Gaumont and the American Mutoscope and Biograph Co. In 1898, he also became a shareholder of the Biograph and Mutoscope Company for France.

In April 1896, Thomas Armat reached an agreement with Edison. Edison's company made and sold the Vitascope, a projector for films created in Edison's studio. The Vitascope was advertised as an Edison invention to help sales, but it was actually invented by Armat and C. Francis Jenkins. Edison had tried to make his own projector but found the Vitascope better.

Edison's film studio produced nearly 1,200 films. Most were short films showing things like acrobats, parades, and fire calls. Examples include Fred Ott's Sneeze (1894), The Kiss (1896), The Great Train Robbery (1903), Alice's Adventures in Wonderland (1910), and the first Frankenstein film (1910). Edison allowed Edwin S. Porter to manage the creative side of the movie business. In 1903, Luna Park in Coney Island announced it would execute an elephant named Topsy. Edison Manufacturing filmed Electrocuting an Elephant, which showed the elephant being killed by electric current.

As the film business grew, competitors often copied and showed each other's films. To protect his films, Edison sent copies of them on long strips of photographic paper to the U.S. copyright office. Many of these paper copies lasted longer and stayed in better condition than the actual films from that time.

In 1908, Edison started the Motion Picture Patents Company, a group of nine major film studios (often called the Edison Trust).

In 1913, movies used live actors and bands to add sound. Edison again believed his kinetophone technology, which could play sound and pictures together, was promising. At the same time, Leon Gaumont was working on similar technology. Both systems needed a skilled projectionist to match the video and sound speeds.

In 1914, Edison fired Porter for unclear reasons. The technical challenges of silent, black-and-white film were mostly solved, and storytelling no longer interested Edison. The kinetophone was hard to use and sell, and Edison's movie business began to decline.

Edison said his favorite movie was The Birth of a Nation. He believed that "talkies" (movies with sound) had ruined things for him. He said, "There isn't any good acting on the screen. They concentrate on the voice now and have forgotten how to act. I can sense it more than you because I am deaf." His favorite actors were Mary Pickford and Clara Bow.

National security

During World War I, Thomas Edison proposed creating a science and industry committee to help the U.S. military with research and advice. He led the Naval Consulting Board in 1915 but attended few meetings because he was deaf. One of the board’s main tasks was to find a location for research work far from Washington, D.C., as frequent visits from government officials might slow progress. However, his suggestion was not followed, and he focused instead on military technology experiments.

At the start of the war, Edison tested methods to improve submarine detection, but the Navy did not adopt them. He allowed Miller Hutchinson to promote his battery technology as a safer alternative to lead batteries on submarines. A submarine crew had suffered injuries from a lead battery leak that created chlorine gas. However, Edison’s nickel-iron batteries produced hydrogen gas, which could be dangerous in submarines. In January 1916, a hydrogen explosion occurred in the USS E-2 during maintenance with Edison’s battery, killing five people. Edison and Hutchinson claimed the explosion was due to operator error, but some naval officials blamed them for overpromoting the battery. The event reduced battery sales but did not harm Edison’s reputation with the Navy.

In 1915, the United States used 75% of the world’s rubber but produced very little. Edison and other business leaders worried about America’s dependence on foreign rubber supplies. Their concerns grew when the Stevenson Plan was introduced in 1921. Edison, along with Ford and Firestone, funded a laboratory with $75,000 to find a domestic rubber source.

Edison remained active in public life despite his age. For his 80th birthday, he gave tours of his experimental garden and shared research on plants that could produce rubber. After testing 17,000 plant samples, he identified Goldenrod (Solidago leavenworthii) as a potential source. In late 1929, he announced that this plant could be bred to produce 12% latex. Edison used a methodical approach to select plants based on latex content, extraction methods, growth speed, and harvesting ease.

Edison’s work in the phonograph industry led him to hire chemists to develop coatings for records to prevent wear. He later licensed a material called Condensite, made from phenol and formaldehyde. At the start of World War I, the U.S. chemical industry relied heavily on European imports. A shortage of phenol, used for explosives and medicine, arose during the war. Edison responded by producing phenol at his Silver Lake facility using methods developed by his chemists. He built two plants capable of making six tons of phenol daily, starting production one month after the war began in Europe. He also built plants in Johnstown, Pennsylvania, and Bessemer, Alabama, to produce benzene, replacing German imports. Edison manufactured aniline dyes and other wartime materials like xylene, p-phenylenediamine, shellac, and pyrax. These efforts became profitable due to wartime shortages. By mid-1915, his production capacity was fully used. Although Edison preferred not to sell phenol for military purposes, he sold surplus to Bayer, which exported it to Germany.

Final years

Henry Ford, a famous car business leader, lived near Thomas Edison at Edison's winter home in Fort Myers. They remained friends until Edison passed away. From 1914 to 1924, Edison and Ford went on yearly car trips. Harvey Firestone and naturalist John Burroughs also joined these trips. The trips helped show people Ford cars, Firestone tires, and Edison's projects. Reporters traveled with them to share news about these trips.

In 1926, at the age of 79, Edison gave the leadership of Thomas A. Edison, Inc. to Charles.

Edison stayed busy in business until his final years. Just months before his death, the Lackawanna Railroad started electric train service from Hoboken to Montclair, Dover, and Gladstone, New Jersey. The trains used overhead wires and direct current, a system Edison supported. Even though he was very weak, Edison was in charge of the first electric train that left Lackawanna Terminal in Hoboken in September 1930. He drove the train for the first mile through Hoboken yard on its journey to South Orange.

In his final years, Edison continued to chew tobacco daily, and his diabetes got worse. Edison died on October 18, 1931, at Glenmont and was buried on the property.

A small container holding Edison's last breath is kept in a test tube at The Henry Ford museum near Detroit. Charles Edison arranged for the test tube to be sent to Ford as a reminder of his father's love for science and their friendship. A plaster model of Edison's face and casts of his hands were also made.

Domestic life

On December 25, 1871, at the age of 24, Edison married 16-year-old Mary Stilwell (1855–1884), whom he had met two months earlier; she was an employee at one of his shops. They had three children:

• Marion Estelle Edison (1873–1965), nicknamed "Dot"
• Thomas Alva Edison Jr. (1876–1935), nicknamed "Dash"
• William Leslie Edison (1878–1937), an inventor and graduate of the Sheffield Scientific School at Yale in 1900.

Edison generally preferred spending time in the laboratory to being with his family. He did not provide Mary much companionship, and she was closest with her sister.

Thomas Jr. was often sick as a child, but Edison left his care in Mary's hands. In her childhood, Marion often visited the laboratory at Menlo Park.

Wanting to be an inventor, but not having much of an aptitude for it, Thomas Jr. became a problem for his father and his father's business. Starting in the 1890s, Thomas Jr. became involved in products and businesses that were dishonest or misleading, selling items to the public as "The Latest Edison Discovery." The situation became so serious that Thomas Sr. had to take his son to court to stop the practices. In exchange for not using the Edison name, Thomas Sr. agreed to pay Thomas Jr. $35 per week (equivalent to $1,254 in 2025). The son began using aliases, such as Burton Willard. Thomas Jr. struggled with alcoholism and depression. He had a short and troubled marriage that began in 1899, which caused scandal for himself and the senior Edison. In 1931, near the end of his life, he obtained a role in the Edison company, thanks to the help of his half-brother, Charles.

When the Edisons moved to New York, they lived near Gramercy Park. Edison neglected his wife after the first few years of their marriage. She enjoyed shopping for fashionable clothes and attending social events. By 1882, Mary's mental health was a serious concern for her doctor.

Mary Edison died at age 29 on August 9, 1884, of unknown causes: possibly from a brain tumor or a morphine overdose. Doctors often prescribed morphine to women at this time to treat various conditions, and researchers believe her symptoms may have been caused by morphine poisoning.

Thomas met Mina Miller at the World Cotton Centennial in December 1884. She was the daughter of Lewis Miller, an inventor who had made significant personal wealth by selling a wheat mower for which he had invented several improvements. He was a co-founder of the Chautauqua Institution and a benefactor of Methodist charities. Mina enjoyed a social lifestyle and practiced a strict Methodist faith throughout her life. She was a family friend of the Gillilands, and Edison met her several times in 1885 while working on a project with Ezra in Boston. He joined her for the Chautauqua gathering in 1885, but their interactions were limited by the religious nature of the event. He proposed to her after the two took a trip in September.

On February 24, 1886, at the age of 39, Edison married the 20-year-old Mina Miller (1865–1947) in Akron, Ohio. They had three children:

• Madeleine Edison (1888–1979)
• Charles Edison (1890–1969)
• Theodore Miller Edison (1898–1992)

Marion did not get along with Mina and moved to Germany in 1894. She returned in 1924 after divorcing her unfaithful husband.

In his second marriage, Edison was also often neglectful of his wife and children. When he was around, he was extremely controlling. He left nearly every aspect of housekeeping and child rearing to Mina and her five maids. One exception was the Fourth of July. Being deaf, Edison enjoyed the loud boom made by fireworks. He made his own fireworks, adding a small amount of TNT.

Edison wrote Mina love letters about missing her while he was away for extended periods.

Madeleine stated she had few childhood memories of her father, and he was typically only home once a week during her childhood. She married John Eyre Sloane.

Theodore was named after Mina's brother, who died in the Spanish–American War shortly before she gave birth. Her sister died in November of that year, and her father died the following February 1899.

Theodore went on to study physics at the Massachusetts Institute of Technology (MIT). After working for Charles while their father stepped down, Theodore decided to become an independent inventor, running his own lab.

Charles studied general science at MIT. He took over his father's business after his death. Later, he served one term as Governor of New Jersey (1941–1944).

In 1885, Thomas Edison bought 13 acres of property in Fort Myers, Florida, for roughly $2,750 (equivalent to $98,542 in 2025) and built what was later called Seminole Lodge as a winter retreat. The main house and guest house are representative of Italianate architecture and Queen Anne style architecture.

Edison purchased a home known as Glenmont in 1886 in Llewellyn Park in West Orange, New Jersey. He sold it to Mina in 1891.

Edison liked boats, cars, and fishing. He drove only on very limited occasions, but, for research purposes, owned several cars, which helped him bond with his son, Charles, whom he encouraged to drive even as a child.

Views

Historian Paul Israel described Edison as a "freethinker." Edison was greatly influenced by Thomas Paine's book The Age of Reason. Edison supported Paine's belief in "scientific deism," explaining, "He has been called an atheist, but atheist he was not. Paine believed in a supreme intelligence, as representing the idea which other men often express by the name of deity." In an October 2, 1910, interview, Edison stated:

Edison was criticized as an atheist for these remarks. Though he avoided public debate, he explained his views in a private letter:

He also said, "I do not believe in the God of the theologians; but that there is a Supreme Intelligence I do not doubt."

Edison explored and promoted ideas in panpsychism, which is the belief that all things have some form of mind or consciousness.

Edison's father was a Democrat who supported the secession of the Confederate States of America. Edison was a lifelong Republican, but he briefly supported Theodore Roosevelt during Roosevelt's third presidential campaign as a Progressive Party candidate. He supported the Republican Party's focus on industrial growth and trade protections.

Edison met several U.S. presidents. He met Rutherford B. Hayes in 1879 to show off the phonograph, and he met Benjamin Harrison in 1890. In 1921, Edison met President Warren G. Harding during a summer tour with the Firestone and Ford caravans. He met Calvin Coolidge in 1924 at Coolidge's home in Vermont. In 1928, Edison received the Congressional Gold Medal, and Coolidge spoke at the ceremony using a radio. In 1929, Herbert Hoover met Edison at Seminole Lodge. Ten months later, Hoover traveled with Edison and Ford to visit Ford's reconstruction of Menlo Park.

Edison supported women's right to vote. In 1915, he said, "Every woman in this country is going to have the vote." Edison signed a statement supporting women's suffrage to counter arguments against it made by Senator James E. Martine. At the time, it was notable that Edison employed women in factory jobs requiring precise hand movements, such as making brush wires for dynamos.

Nonviolence was central to Edison's political and moral beliefs. When asked to serve as a naval consultant during World War I, he agreed to work only on defensive weapons. Later, he said, "I am proud of the fact that I never invented weapons to kill." After a 1911 trip to Europe, Edison criticized the "belligerent nationalism" he observed in many countries.

In May 1922, Edison published a proposal titled A Proposed Amendment to the Federal Reserve Banking System, suggesting a currency backed by physical goods. The proposal did not gain support and was later abandoned.

Awards

The following is an incomplete list of awards given to Edison during his lifetime:

• In 1878, an honorary doctorate degree from Union College
• On November 10, 1881, Officer in the Legion of Honour
• In 1892, membership in the Manchester Literary and Philosophical Society
• In 1889, the John Scott Medal
• In 1899, the Edward Longstreth Medal from The Franklin Institute
• In 1908, the John Fritz Medal
• In 1915, the Franklin Medal from The Franklin Institute
• In 1920, the Navy Distinguished Service Medal
• In 1923, the Edison Medal from the American Institute of Electrical Engineers
• In 1927, membership in the American Philosophical Society
• On May 29, 1928, the Congressional Gold Medal

Primary sources

• The Thomas A. Edison Papers Digital Edition
• The Papers of Thomas A. Edison, a book series with 9 volumes; each volume is available for free download. Volume 1 (1847–1873) online; also download Volume 1. Volume 2 (1873–1876) online; also download Volume 2.