Energy & Power

The Museum's collections on energy and power illuminate the role of fire, steam, wind, water, electricity, and the atom in the nation's history. The artifacts include wood-burning stoves, water turbines, and windmills, as well as steam, gas, and diesel engines. Oil-exploration and coal-mining equipment form part of these collections, along with a computer that controlled a power plant and even bubble chambers—a tool of physicists to study protons, electrons, and other charged particles.
A special strength of the collections lies in objects related to the history of electrical power, including generators, batteries, cables, transformers, and early photovoltaic cells. A group of Thomas Edison's earliest light bulbs are a precious treasure. Hundreds of other objects represent the innumerable uses of electricity, from streetlights and railway signals to microwave ovens and satellite equipment.


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Integral Compact Fluorescent Lamp
- Description
- Inventors seeking to develop energy-efficient lamps could not simply start with a blank piece of paper. They needed to work within the capabilities of existing lighting and power systems. Sometimes even small features had an influence, like the use of the screw-in base and socket.
- What became the standard screw-in lamp base and socket was introduced by Thomas Edison in 1883, and it hasn't changed since. To this day often referred to as an "Edison base," it's formally known as the medium-screw base. While there are other base sizes (and types), the medium-screw base is the most common, especially in residential light fixtures.
- Since sockets for this base are so widespread, designers of compact fluorescent lamps (CFLs) like this 1993 Panasonic "Light Capsule" needed to ensure their products would fit that size. This model EFG16LE lamp is an integral unit--it's all in one piece, including the screw-in base. Other modular lamps used specially designed plug-in bases. The plug-in base has several advantages over the medium-screw base. One of the most important is that if the light fixture takes a plug-in base, one can't use a cheap regular lamp in place of the more expensive CFL.
- But few homes had fixtures with plug-in bases. And lamp makers realized that few homeowners would replace their fixtures just to use the new lamps. So inventors needed to design their lamps with the screw-base, or develop an adaptor.
- Lamp characteristics: Medium-screw base with plastic skirt containing an electronic ballast and starter. Fluorescent tube assembly containing two electrodes, mercury, and an internal phosphor coating. White, G-shaped glass envelope covers the tube assembly. This lamp came in its original package. Rated at 16 watts, it's intended as a replacement for 60 watt incandescent lamps.
- date made
- ca. 1993
- Date made
- ca 1993
- manufacturer
- Matsushita Electric Industrial Co., Ltd.
- ID Number
- 1996.0357.01
- accession number
- 1996.0357
- catalog number
- 1996.0357.01
- Data Source
- National Museum of American History
-
Modular Compact Fluorescent Lamp
- Description
- After decades of constant decline, the cost of electricity in the U.S. began to rise beginning in the 1960s. The change occurred for many reasons, one of which was continually growing demand for electric power. During the 1980s electric utilities that had traditionally concerned themselves with managing the supply of power began adopting so-called Demand Side Management programs (DSM). The idea centered on encouraging the use of special pricing and greater energy efficiency to slow the need for new power plants and transmission lines.
- While many DSM programs focused on commercial and industrial power users, some targeted residential consumers. One popular program involved utilities' swapping regular incandescent lamps for new, energy-efficient compact fluorescent lamps (CFLs). The participating utility purchased a large quantity of CFLs from a lamp maker at a discount and then provided the lamps to consumers at a reduced price, or sometimes for free. Some governments provided subsidies to help cover the costs.
- Bulb-swaps introduced many people to energy-efficient CFLs. They also provided a market demand during the early years of CFL production when lamp makers were still paying for the new production lines needed to make the new lamps. As more lamps were produced, prices began to decline. This "Super Q'Lite" modular lamp from Lights Of America was offered by Washington, DC utility PEPCO in 1994 as part of a DSM program. Using only 27 watts, it replaced a regular lamp that used 100 watts.
- Lamp characteristics: A modular compact fluorescent lamp with two parts—a tube assembly and a base-unit. The original package and coupon book were collected with this lamp. The tube assembly consists of a four-tube glass structure with two electrodes, mercury and an internal phosphor coating. Plug-in style base. The base-unit has a medium-screw shell and houses the ballast and starter equipment. A receptacle on top accepts the plug-in base of the tube assembly.
- date made
- ca. 1992
- Date made
- ca 1992
- Maker
- Lights of America, Inc.
- ID Number
- 1996.0357.05
- accession number
- 1996.0357
- catalog number
- 1996.0357.05
- Data Source
- National Museum of American History
-
Experimental Sulphur-Selenium Lamp
- Description (Brief)
- Demonstration electrodeless selenium and sulfur bulb powered by microwave energy. Selenium is predominate.
- date made
- 1996
- maker
- Fusion Lighting, Inc.
- ID Number
- 1996.0359.05
- catalog number
- 1996.0359.05
- accession number
- 1996.0359
- Data Source
- National Museum of American History
-
Experimental Sulphur-Selenium Lamp
- Description
- In the mid-1990s Fusion Lighting began selling a microwave-powered lighting system. The small, spherical bulbs contained a small amount of the element sulfur that gave a large amount of good quality light when energized by microwaves. Company researchers began investigating other materials to learn more about their new light source and perhaps to discover another saleable product.
- The lamp is from one of those follow-on experiments and contains a mix of sulfur and another element, selenium. Both elements have related properties. Chemists refer to them as Group VI elements since they appear in the same column of the Periodic Table. Fusion researchers felt that these related elements might work well together in the new system. The company donated two other sulfur-selenium lamps from the same experiment that contain mixtures with differing ratios of the two elements.
- Lamp characteristics: A quartz stem with a notched metal sleeve near the bottom serves as the base. The notch locks the lamp into its fixture. The sphere has an argon gas filling with a tiny amount of Krypton-85 to help start the discharge. The orange material condensed on the inner wall is an equal mix of sulfur and selenium. The pattern of condensation indicates lamp was burned vertically. Tipless, G-shaped quartz envelope.
- Date made
- 1997
- maker
- Fusion Lighting, Inc.
- ID Number
- 1996.0359.08
- catalog number
- 1996.0359.08
- accession number
- 1996.0359
- Data Source
- National Museum of American History
-
Microwave-powered ultraviolet lamp
- Description
- When most people think of electric lighting, they think of ordinary lamps used for lighting rooms or shops. But many types of lamps are made for use in highly specialized applications. One example is a successful product made by Fusion Systems. Founded by four scientists and an engineer, the company markets an ultraviolet (UV) lighting system powered by microwaves. Introduced in 1976, the system found a market in industrial processing as a fast, efficient way to cure inks. A major brewery, for example, purchased the system for applying labels to beer cans and quickly curing their inks while the bottles went down the production line. U.S. patents issued for this lighting system include 3872349, 4042850 and 4208587.
- The lamp seen here, referred to as a "TEM lamp" is a typical production unit. As in a fluorescent lamp, this lamp makes ultraviolet light by energizing mercury vapor. Fluorescents and other conventional lamps pass an electric current between two electrodes to energize the mercury. But Fusion's lamp has no electrodes. Instead the lamp is placed in a specially made fixture similar in principle to a household microwave oven. The microwaves energize the mercury vapor directly. A small dose of metal halides is also energized in the lamp. The choice of metal halides allows specific wavelengths of light to be produced to meet different needs.
- Profits made from the production of this industrial lamp were used by the company to support research and development of a microwave-powered lamp that made visible light. Instead of mercury that lamp used sulfur. However this sulfur lamp did not sell well when introduced in the mid-1990s.
- Lamp characteristics: Clear quartz tube containing a metal-halide pellet and a drop of mercury. No electrodes. The air-cooled tube is radiated by microwaves and produces ultraviolet light.
- date made
- ca. 1996
- Date made
- ca 1996
- maker
- Fusion Lighting, Inc.
- ID Number
- 1996.0359.03
- catalog number
- 1996.0359.03
- accession number
- 1996.0359
- Data Source
- National Museum of American History
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Experimental Selenium Lamp
- Description (Brief)
- Demonstration electrodeless selenium bulb powered by microwave energy.
- date made
- 1996
- maker
- Fusion Lighting, Inc.
- ID Number
- 1996.0359.09
- catalog number
- 1996.0359.09
- accession number
- 1996.0359
- Data Source
- National Museum of American History
-
Edison fuse block and fuse
- Date made
- 1881
- maker
- Edison Electric Co.
- ID Number
- EM.180943
- catalog number
- 180943
- accession number
- 24315
- Data Source
- National Museum of American History
-
Fixture for Edison light bulb
- Date made
- 1881
- ID Number
- EM.180939
- catalog number
- 180939
- accession number
- 24315
- Data Source
- National Museum of American History
-
Integral Compact Fluorescent Lamp
- Description
- After the initial introduction of compact fluorescent lamps (CFL) in 1981, many competing lamp companies placed products on the market. The first thirty years of compact fluorescents has seen a wide array of styles and features offered as lamp makers attempt to set their products apart from competitors.
- This U-Lite unit is an integral CFL—the lamp is all one piece. Integral lamps are typically more expensive to replace than modular designs that allow the user to replace only the part that fails. However integral units do not require suppliers to stock replacement parts, and they free consumers from having to try to select the correct part for their device.
- The U-Lite used a slightly larger tube than other companies' CFLs. That simplified the manufacturing process and reduced stress on the phosphor, though it limited the number of tube-legs that could be put on a single lamp. As many as four pairs have been mounted on CFL designs from other makers. More tubes of the size used on the U-Lite would make the lamp too large to install in many fixtures.
- Lamp characteristics: Brass medium-screw base with plastic skirt, glass insulator. A magnetic ballast is housed inside the skirt. Single-bend (T-8) arc-tube with reduced diameter bend and internal phosphor coating. No separate, external envelope.
- Date made
- ca 1987
- date made
- ca. 1987
- maker
- Interlectric Corporation
- ID Number
- 1992.0553.01
- catalog number
- 1992.0553.01
- accession number
- 1992.0553
- Data Source
- National Museum of American History
-
Non-ductile Tungsten Lamp
- Description
- Thomas Edison and others considered element number 6, carbon, ideal for lamp filaments in part because it has the highest melting point of any element. Element number 74, tungsten, has the next highest melting point but it then existed only as a powder. Attempts to make it into a workable form failed until early in the 1900s when a burst of invention occurred in Europe. A pressing technique called "sintering" (squeezing a material into a dense mass) was adopted by several inventors.
- The most commercially successful design proved to be that of Dr. Alexander Just and Franz Hanaman of Austria. Their work on sintering tungsten was based on a prior sintering process developed by Carl Auer von Welsbach for his filament made of osmium. Just and Hanaman made a tungsten and organic paste, squirted it through a die, baked out the organic material, then sintered the tungsten in a mix of gasses. The resulting filament gave about 8 lumens per watt and lasted 800 hours.
- Another Austrian, Dr. Hans Kutzel, used an electric arc to make a tungsten and water paste. He then pressed, baked, and sintered the tungsten in a manner similar to Just and Hanaman's procedure. Yet another pair of Austrians, Fritz Blau and Hermann Remane, adapted the osmium lamp process (they worked for Welsbach) by making a filament from an osmium and tungsten mix. They soon changed their "Osram" lamp filament to tungsten only. (The German word for tungsten is wolfram.)
- All three filaments were brittle and collectively known as "non-ductile" filaments. Individual filaments could not be made long enough to give the proper electrical resistance, so lamps needed several filaments connected end-to-end. U.S. companies quickly licensed rights to all of the non-ductile patents. This particular lamp was made under license by General Electric and sent to the National Bureau of Standards for use as a standard lamp.
- Lamp characteristics: Medium-screw base with glass insulator. Five single-arch tungsten filaments (in series) with 5 upper and 8 lower support hooks. The stem assembly features soldered connectors, Siemens-type press seal, and a cotton insulator. Tipped, straight-sided envelope with taper at neck.
- Date made
- ca 1908
- date made
- ca. 1908
- maker
- General Electric
- ID Number
- 1992.0342.16
- catalog number
- 1992.0342.16
- accession number
- 1992.0342
- Data Source
- National Museum of American History
-
Standard Tungsten Lamp
- Description
- Irving Langmuir received a Ph.D. in physical chemistry in 1906 from the University of Göttingen. He studied under Walther Nernst, who had invented a new type of incandescent lamp only a few years before. In 1909 Langmuir accepted a position at the General Electric Research Laboratory in Schenectady, New York. Ironically, he soon invented a lamp that made Nernst's lamp (and others) obsolete.
- Langmuir experimented with the bendable tungsten wire developed by his colleague William Coolidge. He wanted to find a way to keep tungsten lamps from "blackening" or growing dim as the inside of the bulb became coated with tungsten evaporated from the filament. Though he did not solve this problem, he did create a coiled-tungsten filament mounted in a gas-filled lamp—a design still used today.
- Up to that time all the air and other gasses were removed from lamps so the filaments could operate in a vacuum. Langmuir found that by putting nitrogen into a lamp, he could slow the evaporation of tungsten from the filament. He then found that thin filaments radiated heat faster than thick filaments, but the same thin filament–wound into a coil–radiated heat as if it were a solid rod the diameter of the coil. By 1913 Langmuir had gas–filled lamps that gave 12 to 20 lumens per watt (lpw), while Coolidge's vacuum lamps gave about 10 lpw.
- During the 1910s GE began phasing-in Langmuir's third generation tungsten lamps, calling them "Mazda C" lamps. Although today's lamps are different in detail (for example, argon is used rather than nitrogen), the basic concept is still the same. The lamp seen here was sent to the National Bureau of Standards in the mid 1920s for use as a standard lamp.
- Lamp characteristics: Brass medium-screw base with skirt and glass insulator. Two tungsten filaments (both are C9 configuration, mounted in parallel) with 6 support hooks and a support attaching each lead to the stem. The stem assembly includes welded connectors, angled-dumet leads, and a mica heat-shield attached to the leads above the press. The shield clips are welded to the press. Lamp is filled with nitrogen gas. Tipless, G-shaped envelope with neck.
- Date made
- ca 1925
- date made
- ca. 1925
- ID Number
- 1992.0342.23
- accession number
- 1992.0342
- catalog number
- 1992.0342.23
- Data Source
- National Museum of American History
-
Mercury vapor lamp, type H1
- Description
- The type H-1 mercury vapor lamp represented a significant advance in commercial-industrial light sources. Prior to the H-1, mercury lamps contained large amounts of the toxic metal, and most were large and awkward to use. The H-1 featured a small amount of mercury contained in an internal hard-glass "arc-tube" mounted inside the lamp. Compared to previous mercury lamps, the H-1 was a compact and convenient device.
- This particular unit is a first generation model from about 1934. A wire grid seen wrapped around the arc-tube helps the unit to start. Later models used a special small electrode for that task. Use of the internal arc-tube allowed the lamp to operate at high internal pressure, resulting in better energy efficiency. While not the first high-pressure mercury vapor lamp, mass production of the H-1 and its ease of use led to its wide adoption. Today's mercury vapor and metal halide lamps can be considered refinements of the H-1.
- Lamp characteristics: A brass mogul-screw base with glass insulator. Hard-glass arc-tube with mercury drops visible on the inner wall. Two mandrel and re-coiled tungsten electrodes. Dumet and stranded wire leads connect the base to the electrodes. Starting electrode-grid wrapped around arc-tube and connected to frame. There is no starting resistor in this lamp. Welded connectors. Tipless, T-shape envelope. 400-watt rating.
- Mercury vapor lamps are one type of discharge lamp. Other types are fluorescent and neon tubes. They make light by passing an electric current through a gas, and require additional devices called ballasts to operate properly (not seen in the pictures). More information about how discharge lamps operate is on our website Lighting A Revolution.
- Date made
- ca 1934
- date made
- ca. 1934
- maker
- General Electric Company
- ID Number
- EM.318195
- catalog number
- 318195
- accession number
- 232822
- Data Source
- National Museum of American History
-
Battery: Voltaic Pile
- Description
- In 1800, Alessandro Volta of Italy announced his invention of a device that produced a small but steady electrical current. His "voltaic pile" operated by placing pieces of cloth soaked in salt water between pairs of zinc and copper discs, as seen in this 1805 pile from Canisius College. Contact between the two metals creates a difference in potential (or pressure, or "voltage"), which in a closed circuit produces electric current. Voltaic piles mark the origin of modern batteries.
- Before Volta's invention, electrical researchers like Benjamin Franklin worked with static charges. They learned much, but were limited by the fact that the electrical discharge was at very high potential and very low current; it also could be produced only in very short spurts. A source of flowing current allowed wider-ranging experiments that resulted in greater understanding of the links between electricity and other natural phenomena, including magnetism and light and heat. Batteries attracted the attention of many scientists and inventors, and by the 1840s were providing current for new electrical devices like Joseph Henry's electromagnets and Samuel Morse's telegraph.
- Date made
- 1805
- associated person
- Volta, Alessandro
- ID Number
- EM.323886
- catalog number
- 323886
- accession number
- 252896
- Data Source
- National Museum of American History
-
Experimental fluorescent lamp
- Description
- The development of practical fluorescent lamps took decades, and many researchers contributed. Julius Plucker and Heinrich Geissler made glowing glass tubes in the 1850s, about the time George Stokes discovered that invisible ultraviolet light made some materials glow or "fluoresce." Alexandre Edmond Becquerel put fluorescent materials in a Geissler tube in 1859, though his tubes did not last long. Carbon dioxide-filled tubes by D. McFarlan Moore and mercury vapor tubes by Peter Cooper Hewitt around 1900 gave practical experience with gas-filled, discharge lamps and inspired the neon tubes of Georges Claude.
- In 1926 Friedrich Meyer, Hans Spanner, and Edmund Germer of Germany patented an enclosed glass tube containing mercury vapor, electrodes at either end, and a coating of fluorescent powders called phosphors. This incorporated all of the features we see in modern fluorescent tubes, but their employer did not pursue development. William Enfield of General Electric saw phosphor-coated neon tubes in France in the early 1930s, and heard that European researchers were developing a fluorescent lamp. An especially urgent 1934 letter from a consultant, Nobel-laureate Arthur Compton, coming on the heels of European breakthroughs in low-pressure sodium and high-pressure mercury lamps, spurred both GE and its licensee Westinghouse into combined action.
- Enfield created a team led by George Inman, and by the end of 1934 they made several working fluorescent lamps, including the one seen here. To save time, the team adopted the design of an existing tubular incandescent lamp in order to make use of available production equipment and lamp parts. Speed was important. In addition to European competitors, American companies like Sylvania were also working on fluorescents. A second GE group under Philip Pritchard worked on production equipment. Other GE groups in Schenectady and in Ft. Wayne assisted in developing ballasts and resolving problems of circuit design.
- In 1936 GE and Westinghouse demonstrated the new lamp to the U.S. Navy (that lamp is in the Smithsonian's collection). The public finally saw fluorescent lamps in 1939 at both the New York World's Fair and the Golden Gate Exposition in San Francisco. These early lamps gave twice the energy efficiency of the best incandescent designs. Production of fluorescent lamps, slow at first, soon soared as millions were installed in factories making equipment for the American military during World War 2.
- Lamp characteristics: Double-ended without bases. Flat presses with an exhaust tip near one press. A tungsten electrode, CC-6 configuration coated with emitter, is set at either end. A mercury pellet is loose inside the lamp. The clear T-7 glass envelope has a phosphor coating covering about 3 inches (8 cm) of the lamp near the center.
- date made
- ca. 1934
- Date made
- ca 1934
- manufacturer
- General Electric
- ID Number
- 1997.0388.41
- accession number
- 1997.0388
- catalog number
- 1997.0388.41
- Data Source
- National Museum of American History
-
Pre-production Electronic Halarc Lamp
- Description (Brief)
- Pre-production GE metal halide lamp for indoor use.
- date made
- ca 1980
- maker
- General Electric Co.
- ID Number
- 1996.0080.01
- accession number
- 1996.0080
- catalog number
- 1996.0080.01
- Data Source
- National Museum of American History
-
Edison chemical-type electric meter
- Date made
- ca1882
- ca 1882
- associated person
- Edison, Thomas Alva
- maker
- Edison Electric Co.
- ID Number
- EM.262476
- catalog number
- 262476
- accession number
- 52260
- Data Source
- National Museum of American History
-
Experimental Compact Fluorescent Lamp
- Description
- Ordinary lamps give good quality light and can be designed for all manner of special tasks. However, they waste a tremendous amount of energy in the form of heat. The steep rise in energy prices during the 1970s spurred a burst of invention aimed at developing lamps that gave more lumens per watt—the lighting equivalent of miles per gallon in cars.
- Much of the invention took place in the laboratories of major lighting companies like General Electric and Sylvania. But inventors outside the corporate labs also offered ideas and new devices. One such inventor was Donald Hollister of California. A UCLA graduate with experience in plasma physics, Hollister patented a small fluorescent lamp called the "Litek." The lamp seen here is a hand-made prototype from 1979.
- Most fluorescent lamps, large and small, operate by passing an electric current through a gas between two electrodes. The current energizes the gas that in turn radiates ultraviolet (UV) light. The UV is converted to visible light by a coating of phosphors inside the glass envelope of the lamp. Electrodes are responsible for much of the energy lost in a fluorescent lamp and are usually the part of the lamp that fails. Hollister's design was "electrodeless," and used high-frequency radio waves instead of electrodes to energize the gas.
- The Litek lamp worked in the laboratory, and Hollister received funding from the U.S. Department of Energy to refine the design. That proved more difficult than expected though. The electronic components available at the time were expensive and generated too much heat. Hollister tried to compensate with the massive heat-dissipation fins set below the bulb, but this added to the cost. Also, as an independent inventor Hollister could not just focus on research. He had to perform administrative tasks that researchers in corporate labs did not, and the project lagged. In the end the Litek did not reach the market, though in the 1990s the major companies all began selling electrodeless fluorescent lamps. These built on the work of several inventors, including Hollister's.
- Lamp characteristics: Nickle-plated brass medium-screw base shell with brass retainer and plastic skirt. The base insulator is part of skirt. A metal fitting attaches to the skirt to dissipate heat. Tipped, G-shaped envelope with phosphor coating on inner wall and clear tip.
- Date made
- 1979
- maker
- Hollister, Donald
- ID Number
- 1992.0466.01
- catalog number
- 1992.0466.01
- accession number
- 1992.0466
- Data Source
- National Museum of American History
-
Experimental Sulfur Lamp
- Description
- New lighting inventions occasionally appear from unexpected directions. The development of this microwave-powered lamp provides a case in point. In 1990 Fusion Systems was a small company with a successful, highly specialized product, an innovative ultraviolet (UV) industrial lighting system powered by microwaves.
- Discharge lamps typically use electrodes to support an electric arc. Tungsten electrodes are most common, so materials that might erode tungsten can't be used in the lamp and care must be taken to not melt the electrodes. Fusion's lamp side-stepped this problem by eliminating electrodes entirely. Microwave energy from an external source energized the lamp. This opened the way for experiments with non-traditional materials, including sulfur.
- During the 1980s engineer Michael Ury, physicist Charles Wood, and their colleagues experimented several times with adapting their UV system to produce visible light without success. In 1990, they tried placing sulfur in a spherical bulb instead of a linear tube. Sulfur could give a good quality light, but did not work well in the linear tube. Other elements only gave marginal results in the spherical bulb. But when they tested sulfur in the spherical lamp they found what they hoped for: lots of good visible light with little invisible UV or infrared rays.
- They began setting up "crude" lamps like this one (one of the first ten according to Ury) in order to learn more about the new light source. In the mid-1990s Fusion began trying to sell their sulfur bulbs with limited success. The lamp rotated at 20,000 rpm so that the temperature stayed even over the surface, and a fan was needed for cooling. The fan and spin motor made noise and reduced energy efficiency of the total system. Then they found that the bulbs lasted longer than the magnetrons used to generate the microwaves that powered them. Finding inexpensive magnetrons proved too difficult, and the company stopped selling the product in 2002.
- Lamp characteristics: A quartz stem with notch near the bottom serves as the base. The notch locks the lamp into its fixture. The sphere has an argon gas filling, and the yellow material is sulfur condensed on the inner lamp wall. The pattern of condensation indicates lamp was burned base-down. Tipless, G-shaped quartz envelope.
- Date made
- ca 1990
- date made
- ca. 1990
- maker
- Ury, Michael G.
- ID Number
- 1992.0467.01
- catalog number
- 1992.0467.01
- accession number
- 1992.0467
- Data Source
- National Museum of American History
-
Joseph Henry's Yale electromagnet
- Date made
- 1831
- maker
- Henry, Joseph
- ID Number
- EM.181343
- catalog number
- 181343
- accession number
- 26705
- Data Source
- National Museum of American History
-
Rotary electric light switch
- Date made
- 1882
- date made
- 1887
- associated person
- Edison, Thomas Alva
- maker
- Bergmann & Co.
- ID Number
- EM.181754
- catalog number
- 181754
- accession number
- 33261
- Data Source
- National Museum of American History
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