Inventing Edison's Lamp:
Bracketed information [xxx] does not appear on the label.
[Label xL16.1 - Section #2 introduction - Edison free-standing cut out]
Step 2: Invention
[Label xL16.2 - Section #2 introduction - Edison free-standing cut out]
"Aren't you a good deal of a wizard, Mr. Edison?"
(New York Daily Graphic reporter interviewing Edison,
Edison established a laboratory in 1876 in rural Menlo Park, New Jersey, 20 miles
from New York. He was determined to invent things, and he was very successful at
doing so. In 1877, while working on an improved telephone, he invented the
phonograph. Even he was surprised. Others were astounded to hear the human voice
reproduced, and he quickly became a celebrity. He used this popularity to his
advantage, to gain support for further inventions.
Matthew Brady photograph shows Edison in 1878 at age 31.
[Label xL104 - Menlo Park]
"Edison made your work interesting. He made me feel that I was making
something with him. I wasn't just a workman."
(John Ott, long-time Edison associate)
When Edison began work on the light bulb, he had a large advantage over his
competitors--his laboratory at Menlo Park and a dozen assistants. An important part of
his success was his ability to work with these men and to inspire them
Menlo Park Laboratory in 1880; Edison is in the middle. Note that light bulbs have
replaced gas lights overhead.
[label xL18 - timeline]
An Edison Chronology
1847: Born February 11, Milan, Ohio
1859-63: Sells newspapers and sundries on train between Port Huron, Michigan,
1864-67: Years as a traveling telegrapher
1868: Patents first invention, Boston
1869: Works on stock ticker and printing telegraph, New York
1870: First substantial income from an invention (stock ticker)
1871: Marries Mary Stilwell
1874: Quadruplex telegraph (sending four messages over a wire at the same time)
1876: Carbon-resistance telephone transmitter
1879: Incandescent lamp
1882: Pearl Street Station, New York
1883: Discovers and experiments with electrical discharge inside lamp (called
Edison Effect; later basis of vacuum tube)
1884: Wife Mary dies
1886: Marries Mina Miller
1887: Newer, larger laboratory, West Orange, New Jersey
1888-: Motion pictures
1889-95: Concentrated activity on electromagnetic ore-separation work,
Ogdensburg, New Jersey
- More work on phonograph
- Development of storage battery
1923-: Attempts to find alternative sources of rubber
1929: Inauguration of Menlo Park laboratory as a museum, Dearborn, Michigan
1931: Dies October 18, West Orange, New Jersey
[Label xL24 - credit label near bust of Edison]
Bust of Edison, made by J. Beer, Jr., for the Phrenological Society of America, 1878
[310,582], from Frank Wardlaw, Jr. and Frank Wardlaw
"Wizard" cartoon appeared in New York Graphic in 1877.
[Label xL19 - filaments]
"Your trip to China and Japan on my account to hunt for bamboo or other fiber,
was highly satisfactory ... you found exactly what I required."
Edison letter to William Moore, about 1885
Carbonized vegetable fibers made the strongest filaments. As part of a world-wide
search, Edison sent William Moore to the Far East. He collected thousands of samples
of bamboo to be tested. The best were from a grove in Yawata, near Kyoto, Japan.
This became the standard for Edison lamps for the next ten years.
Edison had begun his search for an electric light in September 1878, using
electricity to heat a thin wire until it glowed. He knew he needed a material that was a
conductor with a high melting point and tried a number of different metals and metal
oxides, but their low resistance made them inefficient. In September 1879, he
experimented with thin filaments of carbon, and by the end of the year he had a practical
The carbon filament was thin enough so that it had a relatively high resistance--
much higher than the wires leading from the generator. This meant that most of the
energy would be used in the light bulb and not in the distribution system, a critical factor
that distinguished Edison s invention from all others.
Edison got his carbon filaments by baking vegetable fibers, which he reasoned
would leave the carbon atoms strongly linked together. Thread worked, cardboard was
better, and even better was bamboo. He also made improvements in other parts of the
- Platinum filaments and other experimental materials used for lighting elements,
1878 and 1879 [262,377], from Mrs. George F. Barker.
- Development of carbon filament material 1879 [320,526], from IBM (William J.
In case at lower right:
- Cut cardboard before being baked, from U.S. Park Service
- Bamboo strips, from IBM (William Hammer collection)
- Plane for making thin bamboo strips [314,259], from Vannevar Bush
- Caliper for judging size of hand-blown bulbs, from Corning Glass Works
- "Paddy" for shaping glass bulb, from Corning Glass Works
A. Photo of Edison drawing of air bubble in platinum wire, January 19, 1879, from
Edison National Historic Site
[Label xL20 - Books and bulbs]
"In 1877 ... I commenced the practice of placing notebooks all over my
Edison testimony, 1880
Recording notes is a critical element of the inventive process, especially when
several people are involved. Notes are also valuable in patent cases and, eventually, to
historians. In the case below are several of Edison's notebooks.
In case at right:
- New Year's Eve lamp with cardboard filament, 1879. Notice the tip, which shows
where the lamp was sealed at the point where the vacuum pump was attached.
[310,578], from Frank A. Wardlaw, Jr. and Frank A. Wardlaw
- Lamp with bamboo filament, 1880. Also, a screw base has been added, and the
glass is pressed against the lead-in wires, making a simpler seal. [181,798], from
General Electric Co.
2a. Socket, 1880 [320,503], from IBM, William Hammer collection.
- Lamp with filament copper-plated to leads, 1880 [318,629], from Princeton
- Lamp with new screw base, 1881 [181,799], from General Electric Co.
- Plaster-based lamp that was easier to form than wood, 1881 [180,934], from J. E.
5a. Socket, 1881 [320,735], from IBM (William J. Hammer collection)
- Screw base lamp with thread-pitch and diameter still in use today, 1881 [318,664],
from Princeton University
- Screw base lamp with lip removed, due to improved bond between glass and
plaster, 1884 [318,677], from Princeton University
[Label xL22 - credit label]
Notebooks from Edison s Laboratory:
Case at lower left:
In fifth notebook notice argument about AC vs DC (1882)
Drawing in seventh notebook is of apparatus to evacuate bulbs (1879)
Reproductions of notebook pages below show Edison's speculations about his lighting
system (August, 1879).
from Edison National Historic Site
[Label xL106 - New Year's Eve]
"On December 31, 1879, special trains brought thousands of people out from
New York to see this spectacular display."
Francis Jehl, Edison assistant, in his recollections, 1939
By early December 1879, Edison was convinced that he had developed a practical
carbon-filament incandescent lamp. As soon as he could produce enough of them, he
strung them around his Menlo Park compound for others to see.
[Label xL23 - credit label]
The Menlo Park Gang
- Front steps of Menlo Park laboratory with Edison holding straw hat, 1880
- Laboratory compound in winter of 1880 as sketched by R. F. Outcault. Center
building is laboratory, front right is library, at rear is machine shop.
- Formal view of Edison and staff at laboratory, 1880; inside laboratory, 1880.
- Boarding house at Menlo Park; laboratory building, about 1879.
Photos from Edison National Historic Site
1. Patents obtained by Edison while he was at Menlo Park, some of them assigned to
2. Two patents and the electric railway at Menlo Park, 1880.
3. Carbon-resistance telephone transmitter (patent model) 1878 [252,622], from U.S.
4. Improved phonograph, 1878 [318,576], from Princeton University
[Label xL107 - photo gallery]
"Billie darling you shouldn't write so meanly about your being a small part of my
life, etc, that is all nonsense; You & the children and the laboratory is all my life. I
have nothing else."
Edison to his wife, Mina, August 8, 1898
Edison's first wife, Mary Stilwell, died in 1884. She was sixteen when they married
and, she was never able to compete with his inventive life. Mina Miller, though only
nineteen when she married the forty-year-old widower in 1886, was much more
successful in keeping him at home. But even she had her difficulties.
- Edison and C. P. Steinmetz, 1922
- Edison, about 1900
- Edison in West Orange Laboratory library, with model of concrete house he was
producing in background, 1911
- Edison resting in West Orange Laboratory, 1911
- Nancy Elliott Edison (mother)
- Samuel Edison, Jr. (father)
- Railway station where Edison learned telegraphy.
- Edison at time clock, about 1921
- Last photo taken of Edison, 1931
- Announcement of intention to be an inventor, 1869
- Naval Consulting Board, with Franklin Roosevelt at left end of first row, Edison third
from left, 1915
- Mina Miller Edison (second wife), about time of wedding in 1886
- Edison and Mina, 1906
- Edison and motion pictures, 1912.
- Matthew Brady photo of Edison with phonograph, 1878
- Edison with dictaphone, 1893
- Edison in West Orange Laboratory, 1893
- Edison in West Orange Laboratory, about 1886
- Edison at about four, about 1851
- Edison at age ten, 1857; Edison "Glenmont" home.
- Edison with staff at West Orange, 1893
- Edison at about 34, 1880-81
- Edison at 31, 1878
- Edward Hurley, John Burroughs, Edison, Henry Ford, Harvey Firestone, R. J. H.
Deloach at start of camping trip, 1918
- Edison with improved phonograph, 1888
- Mary Stilwell Edison (first wife) at about 28, about 1883
- Edison at "Glenmont" home, 1917.
Photos from Edison National Historic Site.