See inside Thomas Edison’s New Jersey lab, where some of America’s biggest inventions took shape

In 1886, when Edison married Mina Miller, his second wife, he already owned a roughly 13-acre estate in the then-rural town. According to the park, Edison had outgrown his lab in Menlo Park by this time and was seeking something bigger.

He enlisted architect Henry Hudson Holly to construct a new lab near his home, which would become his workplace for the rest of his life.

The complex, consisting of six laboratory buildings, employed about 150 to 200 workers at one time.

The space included a chemistry lab, a motion-picture studio, a blacksmith shop, and a pattern shop. In the latter, carpenters created wooden models of machine parts that Edison and his collaborators then used to model metal parts.

For his entire life, Edison’s favorite science was chemistry. After being introduced to the world of test tubes and beakers as a child, he began conducting experiments in his parents’ basement.

The complex’s chemistry lab was “one of the best-equipped chemistry laboratories in the world” when it was completed, according to the park. Here, Edison and his collaborators experimented with rubber, phonograph records, and cement.

His cement would ultimately be used to build the original Yankee Stadium, among other applications.

Edison is credited with creating the first practical light bulb suitable for extended use, building on the ideas of inventors such as the British scientist Joseph Swan.

One of Edison’s chief priorities in his new lab was to improve the electric light, according to the Thomas A. Edison Papers at Rutgers University. Edison also developed a practical alkaline battery at the facility, and the technology was later used in railroads, mining, manufacturing, and ships.

In an 1888 patent application, Edison sought to create a device “that does for the eye what the phonograph does for the ear, which is the recording and reproduction of things in motion,” according to the park.

Inventor William K.L. Dickson, Edison’s most notable collaborator on motion-picture experiments, designed a building known as the Black Maria, which featured a revolving structure and convertible roof to allow for ample sunlight while recording motion pictures.

The studio attracted vaudeville performers and other entertainers who were drawn to the idea of seeing themselves on film, according to the park.

The structure was used less frequently throughout the 1890s, and the lab’s priorities shifted, eventually leading to the Black Maria’s dismantling in 1903. The replica on display today was built in 1954.

Inside the Black Maria replica are recreations of two devices developed by the inventors.

Largely thanks to Dickson’s work, the pair developed the kinetograph, widely considered the world’s first motion-picture camera.

Its sister device, the kinetoscope, allowed people to watch motion pictures via a peephole. For 5 cents, users could watch strips of film at 45 frames per second.

The devices are displayed alongside images of films from the period.

The main laboratory building is home to multiple machinery rooms. These were used for experimenting and creating parts rather than manufacturing, which was left to Edison’s other factories in the area.

The smell of oil regularly permeated the air while workers stood among leather belts, drill presses, and cranes that could lift 6 tons. The machinery rooms were powered by a steam engine before the introduction of electric motors in 1910.

Edison touted the versatility of his facilities, once saying, “We can build anything from a lady’s watch to a locomotive,” according to the park.

Edison’s staff made experimental recordings in the music room on the third floor, testing different-sized horns and recording materials to determine which produced the best sound quality.

In 1877, Edison created the first audio recording that could be played back at his Menlo Park lab. He recorded a humble rendition of “Mary Had a Little Lamb” onto a sheet of tinfoil.

Edison’s phonograph became his favorite invention, though later, his models couldn’t keep up with the competition. Sales were further hurt by the rise of radio in the 1920s.

An adjacent room served as a darkroom for the photographers to develop film. Edison was keen on public relations at the time and used photos to promote his machinery, according to the park.

As time went on, projects in the lab grew quickly in size, necessitating a robust planning process. Collaboration between draftsmen, foremen, and machinists was crucial to coming up with a cohesive blueprint for a product.

The inventor founded numerous companies in electricity, mining, recording, and motion pictures, which were later consolidated under Thomas A. Edison, Inc. Most notably, he founded Edison Electric Light Company shortly after creating his light bulb, which later became Edison General Electric. In the 1890s, the company merged with a competitor to form General Electric.

To support his endeavors, he owned factories that manufactured his products. In 1915, they employed around 10,000 people.

Edison had a net worth of roughly $12 million when he died, according to the park. In today’s money, that’s more than $250 million, per the Bureau of Labor Statistics.

By some accounts, Edison was a difficult boss. At his Menlo Park lab, employees often worked 80-hour weeks, significantly more than the average of 60 hours at the time, according to the Thomas Edison Papers. In 1886, workers went on strike at one of his manufacturing locations in New York City over pay demands.

Edison also sued many other inventors and companies over infringement claims. In one instance, he sued the inventor Granville T. Woods twice over patent control for the railway telegraph, with Woods ultimately winning in court.

The library served multiple purposes beyond being a reading room. A large projection screen sat discreetly on one wall, allowing motion pictures to be shown. Edison used the library to entertain important guests and hold business meetings.

The library is home to about 10,000 books, according to the park. Along the walls, Edison displayed numerous portraits and awards, such as honorary degrees from universities.

Edison used this bed in a library alcove for short naps while working, though the inventor’s famous napping technique usually involved sitting in an armchair. Edison held a steel ball while falling asleep, and when his muscles relaxed and the ball hit the floor, he’d purportedly have a jolt of creativity, according to the journal Science.

He sorted paperwork for his companies, finances, scientific ideas, and other matters in the desk’s many cubbies, per the park.

Though many would be quick to crown the library the best workspace in the lab, Edison preferred Room 12, a quiet and much less extravagant setting on the second floor. Edison used the space to meet with assistants or quietly take notes in private.

The inventor was a prolific notetaker. He and his staff filled more than 3,500 notebooks throughout his career, the park said.

While about half of Edison’s patents were born out of the lab, it was the work of scores of people at any given time that made these achievements possible. For the alkaline storage battery alone, Edison conducted over 10,000 experiments to find the right materials, according to the park.

Experiments for various projects were conducted over the course of years or even decades, showing how many of the luxuries of modern life we enjoy today didn’t come easily.