Search Results

Author:

Du Moncel, Th. comte 1821-1884  Search this

Author:

Bockelmann, J. F  Search this

Bromeis, C  Search this

Ruhmkorff, Heinrich Daniel 1803-1877  Search this

Ruhmkorff, Heinrich Daniel 1803-1884  Search this

Donor:

Dibner, Bern 1897- DSI  Search this

Dibner, Bern DSI  Search this

Physical description:

VI, [2], 176 pages illustrations 22 cm

Type:

Books

Date:

1857

Topic:

Electric apparatus and appliances  Search this

Induction coils  Search this

Call number:

QC645 .D89 G1857

Data Source:

Smithsonian Libraries

EDAN-URL:

edanmdm:siris_sil_274903

Collection Source:

Electricity and Modern Physics, Division of, NMAH, SI.  Search this

Collection Creator:

Applebaugh, William K.  Search this

Container:

Box 1, Folder 46

Type:

Archival materials

Date:

undated

Collection Restrictions:

Collection is open for research.

Collection Rights:

Collection items available for reproduction, but the Archives Center makes no guarantees concerning copyright restrictions. Other intellectual property rights may apply. Archives Center cost-recovery and use fees may apply when requesting reproductions.

Collection Citation:

William K. Applebaugh Papers, 1857-1926, Archives Center, National Museum of American History

See more items in:

William K. Applebaugh Papers

William K. Applebaugh Papers / Series 1: Correspondence

Archival Repository:

Archives Center, National Museum of American History

EDAN-URL:

ead_component:sova-nmah-ac-0638-ref64

Source:

Electricity and Modern Physics, Division of, NMAH, SI.  Search this

Creator:

Hammer, William J. (William Joseph), 1858-1934 (electrical engineer)  Search this

Former owner:

Electricity and Modern Physics, Division of, NMAH, SI.  Search this

Names:

Batchelor, George  Search this

Bell, Alexander Graham, 1847-1922  Search this

Berliner, Emile, 1851-1929  Search this

Curie, Marie  Search this

Curie, Pierre  Search this

Edison, Thomas A. (Thomas Alva), 1847-1931  Search this

Jehl, Francis  Search this

Johnson, Edward H.  Search this

Sprague, Frank J.  Search this

Tesla, Nikola, 1857-1943  Search this

Upton, Francis R.  Search this

Extent:

36 Cubic feet (124 boxes, 3 map-folders)

Type:

Collection descriptions

Archival materials

Correspondence

Photographs

Date:

circa 1847-1989

Summary:

Original documents and papers generated by William J. Hammer and by various companies and individuals with whom he was associated. Includes material related to the research and inventions of Edison, Bell, Tesla, the Curies, etc.

Scope and Contents:

This collection includes original documents and papers generated by Hammer and by various companies and individuals and various secondary sources assembled by Hammer between 1874 and 1934. Hammer's lifelong association with the foremost scientists of his day -- Edison, Bell, Maxim, the Curies, the Wright brothers, and others - afforded him a unique opportunity to collect materials about the development of science along many lines.

This collection, which includes rare historical, scientific, and research materials, was donated by the International Business Machine Corporation to the Museum of History and Technology in 1962 and held by the Division of Electricity. In 1983 it was transferred to the -Archives Center. The collection was badly disorganized when received and contained many fragile documents in poor condition. The collection was organized and arranged as reflected in this register.

The collection documents in photographs, manuscripts, notes, books, pamphlets, and excerpts, the beginnings of electrical technology. In its present state, it comprises four series: Series 1 contains twenty-two boxes of the William J. Hammer Papers, containing both biographical and autobiographical material; Series 2 has twenty boxes of material on Edison; Series 3 consists of thirty-three boxes of reference material; and Series 4 holds twenty-one boxes of photographs and portraits. See the container list beginning on page 39 for more detailed information on the contents of the collection.

Most of the material in the collection is chronologically arranged. However, in some cases alphabetical arrangement has been employed, for example, in the arrangement of portraits of eminent men of electrical science (Series 4, Boxes 78-80, 100-101), and the arrangement of publications (by authors' last names).

Hammer did original laboratory work upon selenium, radium, cathode rays, x-rays, ultra-violet rays, phosphorescence, fluorescence, cold light, and wireless. These aspects of his career are reflected in many parts of the collection: in Series 1 there are articles, notes, diagrams, sketches, graphs,, and correspondence; in Series 3 articles, magazines, news clippings, and bound pamphlets. Tie contributed many technical writings, some of which are found in Series 1.

Papers detailing Hammer's aeronautical activities were transferred to the National Air and Space Museum. They consist of two scrapbooks and one cubic foot of aeronautical photographs of balloons, airplanes, and gliders and one-half cubic foot of correspondence. For further information contact the National Air and Space Museum Archives at (202) 357-3133.

Arrangement:

The collection is divided into four series.

Series 1: William J. Hammer Papers, 1851-1957

Series 2: Edisonia, 1847-1960

Series 3: Reference Materials, 1870-1989

Series 4: Photographs, 1880-1925

Biography of William J. Hammer:

William Joseph Hammer, assistant to Thomas Edison and a consulting electrical engineer, was born at Cressona, Schuylkill County, Pennsylvania, February 26, 1858, and died March 24, 1934. His parents were Martha Augusta Bech (1827-1861) and William Alexander Hammer (1827-1895). He attended private and public schools in Newark, New Jersey, and university and technical school lectures abroad.

On January 3, 1894, Hammer married Alice Maud White in Cleveland, Ohio. They had one daughter, Mabel (Mrs. Thomas Cleveland Asheton). Alice Hammer died in 1906.

In 1878 Hammer became an assistant to Edward Weston of the Weston Malleable Nickel Company. In December 1879 he began his duties as laboratory assistant to Thomas Edison at Menlo Park, New Jersey. He assisted in experiments on the telephone, phonograph, electric railway, ore separator, electric lighting, and other developing inventions. However, he worked primarily on the incandescent electric lamp and was put in charge of tests and records on that device. In 1880 he was appointed Chief Engineer of the Edison Lamp Works. In this first year, the plant under general manager Francis Upton, turned out 50,000 lamps. According to Edison, Hammer was "a pioneer of Incandescent Electric Lighting"! (Hammer's memoranda and notes, Series 2).

In 1881 Edison sent Hammer to London as Chief Engineer of the English Electric Light Co. In association with E. H. Johnson, general manager, Hammer constructed the Holborn Viaduct Central Electric Light Station in London. This plant included three, thirty-ton "Jumbo" steam-powered dynamos (generators), and operated 3,000 incandescent lamps. Holborn was the first central station ever constructed for incandescent electric lighting. Hammer began its operation on January 12, 1882, by lighting the Holborn Viaduct.

In 1882 Hammer also installed a large isolated lighting plant containing twelve Edison dynamos at the Crystal Palace Electric Exposition and the Edison Exhibit at the Paris Electrical Exposition.

At this time Hammer also designed and built the first electric sign. The sign spelled the name "Edison" in electric lights, and was operated by a hand controlled commutator and a large lever snap switch. It was erected over the organ in the Crystal Palace concert hall.

In 1883 Hammer became Chief Engineer for the German Edison Company (Deutsche Edison Gesellschaft), later known as Allegemeine Elektricitaets Gesellschaft. Hammer laid out and supervised the installations of all Edison plants in Germany. While in Berlin he invented the automatic motor-driven "flashing" electric lamp sign. The sign, which flashed "Edison" letter by letter and as a whole, was placed on the Edison Pavilion at the Berlin Health Exposition in 1883.

On his return to the United States in 1884, Hammer took charge of some of Edison's exhibits, including Edison's personal exhibit, at the International Electrical Exhibition held under the authority of the Franklin Institute in Philadelphia. There he built the first flashing "Column of Light." He also became confidential assistant to E. R. Johnson, president of the parent Edison Electric Light Company. Together with Johnson and Frank J. Sprague, he became an incorporator of the Sprague Electric Railway and Motor company. He also was elected a trustee and the company's first secretary.

Hammer installed an all-electric house at Newark, New Jersey in 1884 and he devised various electrical devices and contrivances for an unusual party for friends and colleagues. (See "Electrical Diablerie" beginning on page 6).

At the end of 1884 Hammer became chief inspector of central stations of the parent Edison Electric Light Company. For over two years he made financial, mechanical, and electrical reports on the various stations throughout the United States. During 1886-87 he was chief engineer and general manager of the Boston Edison Electric Illuminating Company. He also acted as contractor for the company. He laid $140,000 of underground tubing and installed Sprague Electric Motors.

In 1888, acting as an independent engineer, he was placed in charge of completing the 8,000 light plant of the Ponce de Leon Hotel in St.Augustine Florida. At the time this was the largest isolated incandescent lighting plant ever constructed. Also in 1888 Hammer was appointed consulting electrical engineer to the Cincinati Centennial Expostition, and as a contractor designed and installed over $40,000 worth of electrical effects.

Hammer was appointed Edison's personal representative remarked, "There are a lot of crowned heads in the Edison business. How many of them am I subservient to?" Mr. Edison answered "You take no instructions except from Thomas A. Edison." Hammer asked "What are your instructions?" Mr. Edison replied, 'Hammer, I haven't any. Go and make a success of it.' In Paris he set up and operated all of Edison's inventions, which embraced nineteen departments and covered 9,800 square feet of space. He also built a huge Edison lamp forty-five feet high employing 20,000 lamps. Edison remarked, 'He had entire charge of my exhibit at the Paris Exposition, which was very successful." This was the largest individual exhibit at the Exposition, costing $100,000. Mr. Edison replied, "I want you to go right out and have a card engraved William J. Hammer, Representative of Thomas A. Edison. You are the only representative I have here," and he complimented him on his work adding, "The French government will do something handsome for you for your work." Hammer replied that he would not raise his hand to get it and did not believe in giving such honors to people who seek them. Mr. Edison said, "You are wrong. You are a young man and such things are valuable. At any rate if there's anyone in this exhibition who deserves recognition, you do, and I'm going to see you get it' (Hammer's memoranda and notes, Series 2). Thirty-four years later, in 1925, through the personal influence of Edison, Hammer was made Chevalier of the Legion of Honor by the French government.

In 1890 Hammer returned to the United States and opened an office as a consulting electrical engineer. He was in private practice until 1925, making reports, conducting tests, and giving expert testimony in patent suits.

On January 31, 1890, Hammer formed the Franklin Experimental Club of Newark where boys could come and carry on experiments, build apparatus, and listen to lectures. Hammer equipped the laboratory at his own expense. One side was an electrical laboratory and the other a chemical laboratory. About forty-five boys joined. Each boy had a key to the club and a section of a bench with his own drawer for keeping notes, tools, and other equipment. In 1892 the structure was destroyed by fire from a saloon next door, ending Hammer's plans for a large and useful institution.

In 1896 Hammer was elected president of the National Conference of Standard Electrical Rules, which prepared and promulgated the "National Electric Code."

In 1902 in Paris, Hammer visited Pierre and Marie Curie, the discoverers of radium and polonium. They gave him nine tubes of radium and one of polonium to bring back to the United States. He also acquired some sulphide of zinc, with which he mixed radium carbonates, producing a beautifully luminous powder. This was the first radium-luminous material ever made. By mixing the powder with Damar varnish he produced the first radium-luminous paint. He was also the first person to make colored (and white) luminous materials. In 1907 he invented and patented a process for producing colored phosphorescent materials by combining phosphorescent and fluorescent substances.

Back in the United States in the fall of 1902 and into 1903, Hammer applied his radium-luminous materials to thirty different objects: luminous dials for clocks and watches, toys, artificial flowers, radium luminous gun sights, taps and pulls for lamp sockets, switches, keyholes, push buttons, telephone transmitters, poison bottle labels, a small plaster figure, push pins, and writing implements among others. He did not patent the invention due to the scarcity and high cost of radium, but later in an important suit involving foreign and American patents of radium-luminous materials, his testimony and that of other noted scientists and professionals of the day who had visited his home and laboratory proved that his work completely anticipated that of all inventors both in the United States and abroad. In 1902 he was one of the first persons to be burned with radium.

Hammer gave eighty-eight lectures on the Curies' work and on radium and radioactive substances. He wrote the first book published on radium, Radium and other Radioactive Substances, 1903. Hammer proposed and used radium for cancer and tumor treatment, successfully treating and curing a tumor on his own hand in July 1903. Tie also supplied several hospitals with radioactive water he had made and conducted extensive experiments with x-rays, cathode-rays, radium-rays, ultraviolet lights, phosphorescence, fluorescence, and cold-light. He was probably the first to suggest many wartime uses for radium-luminous materials, such as airplanes, instruments, markers, barbed-wire, and landing fields.

Hammer also did important work with selenium, a nonmetallic element that resembles sulphur and tellurium chemically. It is obtained chiefly as a by-product in copper refining, and occurs in allotropic forms. A grey stable form varies in electrical conductivity depending on the intensity of its illumination and is used in electronic devices. Hammer invented selenium cells and apparatus, and suggested industrial uses for selenium and other light-sensitive cells.

In 1886 Hammer devised a system for automatically controlling street and other lights by use of a selenium cell. In 1892 he designed a torpedo that could be steered by searchlight and selenium cell. In the early 1900s he suggested many other uses for "light" cells, including burglar alarms, dynamo control, buoy, railroad signaling, automatic gun firing, transmission of music, stethoscope recorder, automatic operating shutters, automatic boiler feed, snow recorder, and electric motor control.

At the St. Louis Exposition of 1904 Hammer was Chairman of the Jury for Telegraphy, Telephony, and Wireless. He was also a member of the "Departmental" Jury ("Applied Science: Electricity") and of the committee appointed to organize the International Electrical Congress at St. Louis in 1904.

In 1906 Hammer received the "Elliott Cresson" gold medal from the Franklin Institute for his "Historical Collection of Incandescent Electric Lamps," accumulated over thirty-four years. This collection received a special silver medal at the International Electrical Exposition at the Crystal Palace, London, England, in 1882, and "the Grand Prize" at the St. Louis Exposition of 1904.

During the First World war Hammer served as a major on the General Staff of the, Army War College, Washington, D.C., where he was attached to the Inventions Section of the War Plans Division and later to the operations Division at the war Department in charge of electrical and aeronautical war inventions. He did special work at the U.S. Patent office, marking and delaying patents that might be useful to the enemy and served on the Advisory Board of Experts attached to the Alien Property Commission. He was elected Historian general of the Military order of the World War (1926-1928) and was a member of the Society of American Military Engineers.

Hammer was an early aeronautics enthusiast and became the owner of one of the first airplanes sold in the United States to an individual. Even in his last few years of his life, Hammer's interest in airplanes did not wane. In 1931, by the permission of the Secretary of the -Navy, Hammer made a twelve-hour flight in the Los Angeles dirigible from the Lakehurst, New Jersey airdrome along the coast of the Atlantic Ocean to New York, flying over New York City at night.

Hammer served on numerous committees. In 1916 he was a member of a special committee, appointed by the Aeronautical Society of America. one of his responsibilities on this committee was to recommend methods for the formation of a reserve force of civilian aviators for the Army. At the start of World War I, Hammer was appointed chairman of a committee on camouflage by the Aeronautical Society. During the war, he flew airplanes and tested sound devices and was also among the first five selected out of thousands for the dissemination of propaganda into many countries. He also examined documents and papers captured from spies and prisoners of war to see if these material contained any technical matter of value to the U. S. Army.

Hammer traveled extensively as a delegate of the Military Order of World War I. For example, in 1922 he attended the aeronautical Congress and Flying Meet in Detroit, Michigan. In the same year he also attended Immigration Conferences of the National Civic Federation in New York.

Between 1922 and 1928 Hammer intensified his efforts in collecting and organizing autographed portraits of eminent scientific men, a project he had been working on for over forty-five years. Tie displayed many of these portraits with his Historical Collection of Incandescent Electrical Lamps in -his New York home. At this time he also prepared an elaborate bibliography on selenium and its industrial and scientific applications.

Major William Joseph Hammer, described by Edison as "my most valuable assistant at Menlo Park" died of pneumonia March 24, 1934.

'Electrical Diablerie':

"ELECTRICAL DIABLERIE"

N.Y. World, January 3, 1885 and Newark, N.J. Daily Advertiser and Journal, January 3, 1885

Some years ago, (1884) on New Year's eve, an entertainment was given at the home of Mr. William J. Hammer, in Newark, N.J., which, for the display of the powers of electricity has seldom, if ever, been equaled. Mr. Hammer, who has for years been associated with Mr. Edison, both in this country and in Europe, desiring to give his old classmates, the "Society of Seventy-Seven," a lively and interesting time, invited them to "an electrical dinner"at his home.

The invitations which were sent out were written upon Western Union telegram blanks with an Edison electric pen. When the guests arrived and entered the gate, the house appeared dark, but as they placed foot upon the lower step of the veranda a row of tiny electric lights over the door blazed out, and the number of the house appeared in bright relief. The next step taken rang the front door bell automatically, the third threw open the door, and at the same time made a connection which lit the gas in the hall by electricity.

Upon entering the house the visitor was invited to divest himself of his coat and hat, and by placing his foot upon an odd little foot-rest near the door, and pressing a pear-shaped pendant hanging from the wall by a silken cord, revolving brushes attached to an electric motor brushed the mud and snow from his shoes and polished them by electricity. As he was about to let go of the switch or button, a contact in it connected with a shocking coil, caused him to drop it like a hot potato. Up-stairs was a bedroom which would be a fortune to a lazy man; he had only to step on the door sill and the gas was instantly lighted. The ceiling was found to be covered with luminous stars, arranged to represent the principal constellations in the heavens-while comets, moons, etc., shone beautifully in the dark. By placing one's head on the pillow, the gas, fifteen feet away, would be extinguished and the phosphorescent stars on the ceiling would shine forth weirdly, and a phosphorescent moon rose from behind a cloud over the mantel and slowly describing a huge arch disappeared behind a bank of phosphorescent clouds on the other side of the room; by pressing the toe to the foot-board of the bed the gas could again be relit.

Pouring a teacup of water into the water clock on the mantel and setting the indicator would assure the awakening of the sleeper at whatever hour he might desire. There was also in the hall outside the room a large drum, which could be set to beat by electricity at the hour when the family wished to arise. The whole house was fitted throughout with electric bells, burglar alarms, fire alarms, telephones, electric cigar lighters, medical coils, phonographs, electric fans, thermostats, heat regulating devices, some seven musical instruments, operated by electricity, etc.

Upon the evening referred to nearly every. piece of furniture in the parlor was arranged to play its part. Sit on one chair and out went the gas, take another seat and it would light again; sitting on an ottoman produced a mysterious rapping under the floor; pressure on some chairs started off drums, triangles, tambourines, cymbals, chimes and other musical instruments; in fact, it seemed unsafe to sit down anywhere. The quests stood about in groups and whispered, each hoping to see his neighbor or a new comer caught napping.

One visitor (Brown) secured an apparently safe seat, and was telling a funny story--he had left electricity far behind--but just as he reached the climax, a pretty funnel-shaped Japanese affair like a big dunce cap, that seemed but a ceiling ornament which was held in place by an electromagnet, dropped from overhead and quietly covered him up, thus silently extinguishing the story and the story-teller.

A big easy chair placed invitingly between the folding doors joining the double, parlors sent the unwary sitter flying out of its recesses by the sudden deafening clamor of twenty-one electric bells hidden in the folds of the draperies hanging in the doorway. In a convenient position stood the silver lemonade pitcher and cup, the former was filled with the tempting beverage, but no matter how much a guest might desire to imbibe one touch convinced him that the pitcher and cup were so heavily charged with electricity as to render it impossible for him to pour out a drink or even to let go until the electricity was switched off from the hidden induction coil.

Some one proposed music, and half a selection had been enjoyed when something seemed to give way inside the piano, and suddenly there emanated from that bewitched instrument a conglomeration of sounds that drowned the voices of the singers, and the keys seemed to beat upon a horrible jangle of drums, gongs and various noise-producing implements which were fastened inside of and underneath the piano.

After the guest were treated to a beautiful display of electrical experiments, under the direction of Mr. Hammer, and Professor George C. Sonn, they were escorted to the dining-room, where an electrical dinner had been prepared and was presided over by 'Jupiter," who was in full dress, and sat at the head of the table, where by means of a small phonograph inside of his anatomy he shouted, "Welcome, society of Seventy-Seven and their friends to Jove's festive board." The menu was as follows: "Electric Toast," "Wizard Pie," "Sheol Pudding," "Magnetic Cake," "Telegraph Cake," "Telephone Pie," "Ohm-made Electric Current Pie," "Menlo Park Fruit," "Incandescent Lemonade," "'Electric Coffee" and "Cigars," etc., and music by Prof. Mephistopheles' Electric Orchestra.

About the table were pretty bouquets, and among the flowers shone tiny incandescent lamps, while near the center of the table was placed an electric fan which kept the air cool and pure, and at each end was a tiny Christmas tree lighted with small incandescent lamps, planted in a huge dish of assorted nuts and raisins. Each lamp had a dainty piece of ribbon attached to it upon which the initials of the Society and the date were printed, and each guest received a lamp to take away with him as a souvenir of the occasion. Plates of iced cakes made in the form of telephones, switches, bells, electric lamps, batteries, etc., stood on each side of the center piece.

Promptly at 12 o'clock, as the chimes of the distant churches came softly to the ears of the assembled quests, pandemonium seemed to change places with the modest dining-room. A cannon on the porch, just outside the door, and another inside the chimney, were unexpectedly discharged; and at this sudden roar, every man sprang back from the table; the lights disappeared; huge fire-gongs, under each chair beat a tattoo. The concussion produced by the cannon in the fireplace caused several bricks to come crashing down the chimney, and as the year of 1884 faded away, the table seemed bewitched. The "Sheol Pudding" blazed forth green and red flames illuminating the room, tiny tin boxes containing 'Greek" fire which had been placed over each window and door were electrically ignited by spirals of platinum iridium wire heated by a storage battery and blazed up suddenly; the "Telegraph Cake" clicked forth messages said to be press reports of the proceedings (it was also utilized to count the guests and click off the answers to various questions put to it); bells rang inside the pastry; incandescent lamps burned underneath the colored lemonade; the thunderbolt pudding discharged its long black bolts all over the room (long steel spiral springs covered with black cloth) and loud spirit rapping occurred under the table. The silver knives, forks and spoons were charged with electricity from a shocking coil and could not be touched, while the coffee and toast (made by electricity) were made rapidly absorbed; the "Magnetic Cake' disappeared; the "Wizard" and "Current Pies' vanished, and 'Jupiter" raising a glass to his lips began to imbibe.

The effect was astonishing! The gas instantly went out, a gigantic skeleton painted with luminous paint appeared and paraded about the room, while Jupiter's nose assumed the color of a genuine toper! His green eyes twinkled, the electric diamonds in his shirt front (tiny lamps) blazed forth and twinkled like stars, as he phonographically shouted "Happy New Year'. Happy New Year!" This "Master of Cererionies' now becoming more gentle, the guests turned their attention to the beautiful fruit piece, over four feet high, that stood in the center of the table. From the fruit hung tiny electric lamps, and the whole was surmounted by a bronze figure of Bartholdils "Statue of Liberty;" uplifted in "Miss Liberty's" right hand burned an Edison lamp no larger than a bean.

The dinner finished, and there was much that was good to eat, notwithstanding the "magical" dishes which they were first invited to partake of, speeches were delivered by Messrs. Hammer, Rutan, McDougall, 'Brown, Duneka, and Dawson, and an original poem was read by Mr. Van Wyck. Upon repairing to the parlors the guest saw Mr. Hammer's little sister, May, dressed in white and mounted upon a pedestal, representing the "Goddess of Electricity:" tiny electric lamps hung in her hair, and were also suspended as earrings, while she held a wand surmounted by a star, and containing a very small electric lamp.

Not the least interesting display of electricity took place in front of the house, where a fine display of bombs, rockets, Roman candles, Greek fire and other fireworks were set off by electricity, which was by the way, the first time this had been accomplished. The guests were requested to press button switches ranged along the front veranda railing thus causing electricity from a storage battery to heat to a red heat tiny platinum iridium spirals attached to each fuse of the various pieces of fireworks thus sending up rocket after rocket, as well as igniting the other pieces which had been placed in the roadway in front of the house.

An attempt was made to send up a large hot air balloon to which was attached a tiny storage battery and an incandescent signal lamp but a sudden gust of wind caused the ballon to take fire as it rose fr(xn the ground. This constituted the only experiment made during the evening which was not an unqualified success. The innumerable electrical devices shown during the progress of the dinner were all operated by Mr. Hammer, who controlled various switches fastened to the under side of the table and attached to a switchboard, which rested on his lap, while the two cannons were fired by lever switches on the floor, which he operated by the pressure of the foot. Electricity was supplied by primary and storage batteries placed under the table. After an exhibition of electrical apparatus and experiments with a large phonograph, the guests departed with a bewildered feeling that somehow they had been living half a century ahead of the new year."

Expositions and Exhibitions:

The many Expositions held at the end of the 19th and the beginning of the 20th centuries were important for the Edison Electric Company's future business. In particular the Paris Electrical Exposition, 1881, and the Crystal Palace Exposition in London in 1892 were introductions for the company's international business enterprises. Edison, therefore, sent his ablest men from the Menlo Park staff (Batchelor, Hammer, Jehl, Johnson) to Europe to oversee the installation and promotion of the company's exhibits.

THE INTERNATIONAL PARIS EXPOSITION OF 1881

The International Paris Electrical Exposition was held during the summer of 1881. Many of Edison's electric lighting systems, ranging from arc lights to incandescent devices, were exhibited. A model of the Edison central-station lighting system showed an arrangement of incandescent lights within a complete electrical distributing system, including novel appliances and controls of the Edison system. "The completeness of its conception made a profound impression on the foremost European electrical engineers of that era." (Josephson, Matthew. Edison, A Biography. p. 252). Edison also exhibited his first "Jumbon generator. It was "direct-connected" to its driving engine, another area in which Edison pioneered. Edison improved upon the original design of William Wallace's "Telemachon' - a generator coupled to a water-powered turbine. Wallace had earlier in the decade produced the first dynamo in America.

Charles Batchelor headed the Edison exhibits within Paris. Edison received many gold medals and diplomas and was awarded the ribbon of the Legion of Honor.

The William J. Hammer Collection contains various reports and catalogues exhibited at the International Exposition of Electricity. (Series 3, Box 44, Folders 1-4)

THE CRYSTAL PALACE EXHIBITION OF 1882

At the Crystal Palace Exhibition of 1882 in London, Edison displayed a great many of his inventions, including: the steam dynamo; specimens of street pipes and service boxes used in the Edison underground system of conductors, and the system of house conductors with devices for preventing abnormal increase of energy in house circuits; apparatus for measuring the resistance of his lamps, for measuring the energy consumed in lamps, and rheostats for restoring currents; also thermogalvano-meters, carbon rheostats, dynamometers, photometers, carbon regulators, Weber meters,, current regulators, and circuit breakers for controlling electric light circuits; the carbon relay, the pressure relay, and the expansion relay; the telegraph system in Morse characters; and the Roman character automatic telegraph.

Thomas Edison also exhibited the carbon telephone, the musical telephonograph, telephone repeater, and numerous apparatus for demonstrating the method of varying the resistance of a closed circuit by contact with carbon, illustrative of the experimental factors of the Edison carbon transmitter. Incandescent lamps, the process of the manufacture of lamps, and various designs of electric light chandeliers were also on display.

Hammer won the silver medal at the exposition for the first complete development of the incandescent electric lamp from its initial stages to date. At the exhibition the first hand-operated flashing electric lamp sign was displayed, which was invented and built by Hammer.

The collection contains photographs of the Edison dynamo, and the Edison Electric Lighting Plant of 1882 erected by Hammer. The official Catalogue of the International Electric and Gas Exhibition, and various articles from the Daily Telegraph, Daily Chronicle, and Daily News are also included within the collection (Series 4, Box 99 and Series 3, Box 42, Folder 1-2).

THE BERLIN EXPOSITION OF 1883.

The Berlin Exposition of 1883 had the first motored flashing electric sign designed, built and operated by Hammer. The electric sign spelled out the word "Edison" letter by letter and was used on the Edison pavilion in the Health Exposition. It has most features of today's flashing sign.

The collection contains two photographs of the first flashing sign (Series 4, Box 99).

THE FRANKLIN INSTITUTE INTERNATIONAL ELECTRICAL EXHIBITION OF 1884

The Franklin Institute International Electrical Exhibition was held in Philadelphia from September 2 to October 14, 1884. Many of Edison's companies had display booths at the exhibition. The Edison Electric Light Company showed in operation their system of house lighting as supplied from a central station. The Edison Company for Isolated Lighting exhibited their system of lighting factories, hotels, hospitals, and other places situated beyond the reach of a central lighting station. A full assortment of Edison lamps and dynamos also made up parts of other exhibits. Also displayed at the exhibition was the first flashing column of light, which Hammer designed and built.

Included within the collection are a variety of photographs of the exhibitions. Four pamphlets also are contained in the collection (Series 3, Box 1, Folder 3), (Series 4, Box 99).

THE EXPOSITION OF THE OHIO VALLEY AND THE CENTRAL STATES OF 1888

The Exposition of the Ohio Valley and Central States, in Cincinnati from July 4 to October 27, was in honor of the one hundredth anniversary of the settlement of Cincinnati. The exposition showed the progress and ramifications of the first hundred years of this settlement.

The space occupied by permanent buildings was greater than that covered by any building for exhibiting purposes on the Western continent. T',ie exposition developed the Electric Light Plant to make a special feature of electric lighting in the evening. Several companies used this opportunity to make exhibits of their apparatus and for their equipment to be used for illumination. The Edison Lamps were used for displays in showcases and pavilions of exhibitors of the Park Building.

The collection contains photographs of the halls of the exposition and a poster which is a souvenir of the electrical display of the exposition. An official Guide of the Centennial Exposition of the Ohio Valley and Central States is included within the collection. (Series 4, Box 99), (Series 3, Box 42, Folder 4).

THE SUMMER CARNIVAL AND ELECTRICAL EXHIBITION, ST. JOHN, NEW BRUNSWICK, 1889

The Summer Carnival and Electric Exhibition held at St. John, New Brunswick, Canada was to celebrate the opening of the Canadian Pacific Short Line to St. John and Portland. The Electrical Exhibition was the most popular of the displays present, containing the Monster Edison Lanm, the Mysterious Electric Fountain, and many other inventions.

The William J. Hammer Collection contains a poster that illustrates some of the leading exhibits at the Electrical Exhibition (Series 4, Box 99).

PARIS UNIVERSAL EXPOSITION OF 1889

The Universal Exposition of 1889 held in Paris was larger than all previous expositions held there. The famous Eiffel Tower was its principal attraction.

A large portion of the exhibit hall within the Palace of Mechanical Industries contained Thomas Edison's electrical inventions, including various electric lamps for use in houses. Variations of the telephone also were shown. During the Paris Exposition Europeans were exposed to the phonograph for the first time. Hammer represented Edison's interests at the Paris Exhibition.

The collection contains articles from New York World, New York Herald and Electrical World on Edison's exhibits at the Paris Exposition (Series 3, Box 44, folder 6). A scrapbook of photographs from the exhibition showing exhibit buildings and halls and loose photographs showing Edison's exhibits are included in the collection (Series 4, Box 98).

THE CRYSTAL PALACE EXHIBITION OF 1892

The Crystal Palace Exhibition of 1892 was held in London. Hammer displayed a great variety of products in the machine room of the Electrical Exhibition. Sockets for controlling individual incandescent lamps on alternating currents and the Ward Arc Lamp for use on incandescent circuits were just a few of the items displayed. Edison's companies displayed specimens of all types of incandescent electric lamps for public and private illumination. They also displayed primary batteries for use in telegraphy, telephony, household work, and engines.

The William, J. Hammer Collection contains a variety of photographs of the electrical exhibition. The Official Catalogue and Guide of the Electrical Exhibition is also contained within the collection (Series 4, Box 99), (Series 3, Folder 2, Box 42).

LOUISIANA PURCHASE EXPOSITION, 1904

The Louisiana Purchase Expostition of 1904, held in St. Louis, Missouri from April 30 to December 1, celebrated the centennial of the Louisiana Purchase. The nineteen million people who attended made it the largest exposition ever. The year 1904 marked the twenty-fifth anniversary of Edison's invention of the carbon filament lamp and central power station system.

F.J.V. Skiff, the exhibits classifier for the fair, developed a twofold classificatory arrangement. He organized exhibits in a sequential synopsis corresponding to the sixteen different departments of the exposition. The principal exhibition buildings were built in the shape of a fan. The departments of education, art, liberal arts, and applied sciences-including electricity - headed the classification, Skiff noted, because they "equip man for the battle and prepare him for the enjoyments of life.' Departments devoted to displays of raw materials such as agriculture, horticulture, !inning, forestry, fish and game came next. Anthropology, social economy, and physical culture concluded the classification.

The Hammer collection contains photographs of Hammer with other Chairmen of Domestic and Foreign Jurors of the Electricity Section of the International Jury of Awards of the Louisiana Exposition and Hammer as chairman of the jury on telegraphy, telephony, and wireless. (Series 4, Box 102). A pamphlet by the American Telephone and Telegraph Company on the exhibit of the Radiophone at the Department of Applied Science is also part of the collection (Series 3, Box 42, Folder 5).

THE PANAMA-PACIFIC EXPOSITION OF 1915

The Panama Pacific Exposition celebrated the opening of the Panama Canal and the four hundredth anniversary of the European discovery of the Pacific Ocean. It was held in San Francisco from February 20 to December 4, 1915. Approximately nineteen million people attended the exposition.

The eleven main buildings of the exposition were grouped around a central court of the Sun and Stars at the entrance of which was the famous Tower of Jewels. The main group of exhibits comprised the Palaces of Education, Liberal Arts, Manufactures, Varied Industries, Mines,

Transportation, Agriculture, Horticulture and all kinds of food products. During the exposition special days were set aside to honor industrialists Henry Ford and Thomas Edison. The Pacific Gas and Electric Company provided a large searchlight to flash out a Morse code greeting on the nighttime sky for their arrival.

The William J. Hammer Collection contains a pamphlet on the "Illumination of the Panama-Pacific International Exposition." The pamphlet describes the lighting of the exposition, and the use of arc lamps ' searchlights, incandescent electric lamps, and gas lamps (Series 4, Box 99), (Series 3, Box 43).

Provenance:

Collection donated by IBM, 1962.

Restrictions:

Collection is open for research.

Rights:

Collection items available for reproduction, but the Archives Center makes no guarantees concerning copyright restrictions. Other intellectual property rights may apply. Archives Center cost-recovery and use fees may apply when requesting reproductions.

Topic:

Fluorescence  Search this

Electrical engineering  Search this

Incandescent lamps  Search this

Phosphorescence  Search this

Selenium cells  Search this

Cathode rays  Search this

X-rays  Search this

Radium  Search this

Genre/Form:

Correspondence -- 1930-1950

Photographs -- 1850-1900

Photographs -- 20th century

Citation:

William J. Hammer Collection, Archives Center, National Museum of American History

Identifier:

NMAH.AC.0069

See more items in:

William J. Hammer Collection

Archival Repository:

Archives Center, National Museum of American History

EDAN-URL:

ead_collection:sova-nmah-ac-0069

Creator:

Von Fuchs, George, Dr.  Search this

Halacsy, Andrew, Dr. (electrical engineer)  Search this

Names:

American Institute of Electrical Engineers.  Search this

Extent:

0.66 Cubic feet (2 boxes)

Type:

Collection descriptions

Archival materials

Date:

1884-1885

Summary:

Contains information directly relevant to the transformer's 1884-1885 evolution and secondary references and articles which von Fuchs and Halacsy referred to in their research.

Scope and Contents note:

The collection is divided into two boxes- the-first containing information directly relevant to the transformer's 1884-85 evolution and the second containing secondary references and articles which von Fuchs and Halacsy referred to in their research. The original material box contains the following: eight figures of inventors and their developments; patents submitted between 84 and 85 and divided into the four categories of parallel, series, open iron core, and closed iron core; a paper by the compilers on transformer history; and an assorted collection of mimeographs of research notes and correspondences. The reference box contains secondary articles on the history of the transformer which were written by both American and German authors at the time of the advances and recently.

Arrangement:

Chronological arrangement.

Biographical / Historical:

Dr. Andrew Halacsy and Dr. George von Fuchs concentrate on the 1884 and 1885 development of the transformer and have written several papers together on the transformer's creation. They brought this documentation together in 1960, when both were members of the American Institute of Electrical Engineers.

When Michael Faraday discovered the induction principle in 1831, he found that if a conductor were put into an alternating current path, then a voltage would be induced in the conductor. Until 1884 this discovery was not followed up, but as the means of production for AC power expanded, inventors began searching for ways to control this energy form. The final product of two years of patent competition based on Faraday's induction work was the modern transformer.

If a voltage were induced in the core of the transformer by the input AC source, then an output AC source could be started from the induction begun by the magnetic flux in the core. Essentially, energy can be transferred from a primary AC source to a secondary AC source by purely electromagnetic means. Induction replaces an electrical connection. If the primary leg contains more wire coils than the secondary, then the transformer drops voltage over the core and is called a step-down transformer. If the secondary coil is built with more wire coil than the primary, voltage is increased over the coil, and the device becomes a step-up transformer. Several transformer models were produced in the U.S. and foreign countries in 1884, but the Hungarian three man team of Deri, Blathy, and Zipernowsky are credited with the first industrially useful construction. In 1885, at a Budapest exhibition, first utilized a closed iron core and first connected the primary and secondary in parallel.

Restrictions:

Collection is open for research.

Rights:

Collection items available for reproduction, but the Archives Center makes no guarantees concerning copyright restrictions. Other intellectual property rights may apply. Archives Center cost-recovery and use fees may apply when requesting reproductions.

Topic:

Electrical engineers  Search this

Citation:

Halacsy and Von Fuchs Documentation for Transformer History, 1884-1885, Archives Center, National Museum of American History.

Identifier:

NMAH.AC.0052

Archival Repository:

Archives Center, National Museum of American History

EDAN-URL:

ead_collection:sova-nmah-ac-0052

Collection Creator:

Du Mont, Allen B. (Allen Balcom), 1901-1965  Search this

Collection Source:

Electricity and Modern Physics, Division of, NMAH, SI.  Search this

Container:

Box 64, Item 156-36

Type:

Archival materials

Slides

Collection Restrictions:

Collection is open for research. Gloves must be worn when handling unprotected photographs and negatives. Special arrangements required to view materials in cold storage. Using cold room materials requires a three hour waiting period. Only reference copies of audiovisual materials may be used. Contact the Archives Center for more information: archivescenter@si.edu.

Collection Rights:

Collection items available for reproduction, but the Archives Center makes no guarantees concerning copyright restrictions. Other intellectual property rights may apply. Archives Center cost-recovery and use fees may apply when requesting reproductions.

Collection Citation:

Allen Balcom Du Mont Collection, 1929-1965, Archives Center, National Museum of American History.

See more items in:

Allen Balcom Du Mont Collection

Allen Balcom Du Mont Collection / Series 17: Addenda / Lantern Slides

Archival Repository:

Archives Center, National Museum of American History

EDAN-URL:

ead_component:sova-nmah-ac-0018-ref2046

Maker:

W. H. Burnap  Search this

Measurements:

overall: 11 cm x 22 cm x 10.2 cm; 4 5/16 in x 8 11/16 in x 4 in

Object Name:

Electrotherapeutic Apparatus

Other Terms:

Electro-Magnetic Machine; Electrotherapeutic Apparatus; Medicine

Place made:

United States: New York, New York City

Date made:

c.1850

c.1850s

Date made:

nineteenth century

ID Number:

MG.M-10487

Catalog number:

M-10487

Accession number:

251552

See more items in:

Medicine and Science: Medicine

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a6-f1b1-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_723487

Measurements:

overall - from catalog card: 4 in x 6 in x 4 in; 10.16 cm x 15.24 cm x 10.16 cm

flywheel - from catalog card: 2 5/8 in; x 6.6675 cm

overall: 4 in x 4 1/2 in x 6 in; 10.16 cm x 11.43 cm x 15.24 cm

Object Name:

toy, electric motor

Date made:

ca 1900

Related Publication:

Maass, Eleanor A.. Greville Bathe's "Theatre of Machines": The Evolution of a Scholar and His Collection

Credit Line:

Bequest of the Estate of Greville I. Bathe

ID Number:

MC.329036

Catalog number:

329036

Accession number:

278175

See more items in:

Work and Industry: Mechanical and Civil Engineering

Engineering Steam Toys and Models

Engineering, Building, and Architecture

Family & Social Life

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a6-84b1-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_847171

Physical Description:

tin (overall material)

white metal (overall material)

Measurements:

flywheel-from catalog card: 2 5/8 in; x 6.6675 cm

base-from catalog card: 8 1/2 in x 6 in; x 21.59 cm x 15.24 cm

overall: 4 in x 8 3/8 in x 5 3/4 in; 10.16 cm x 21.2725 cm x 14.605 cm

Object Name:

toy, electric motor & pump

Date made:

ca 1900

Related Publication:

Maass, Eleanor A.. Greville Bathe's "Theatre of Machines": The Evolution of a Scholar and His Collection

Credit Line:

Bequest of the Estate of Greville I. Bathe

ID Number:

MC.329040

Catalog number:

329040

Accession number:

278175

See more items in:

Work and Industry: Mechanical and Civil Engineering

Engineering Steam Toys and Models

Engineering, Building, and Architecture

Family & Social Life

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a6-9fa9-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_847236

Physical Description:

brass (overall material)

cast iron (overall material)

nickle plating (overall material)

Measurements:

overall: 4 3/4 in x 40 in x 6 in; 12.065 cm x 101.6 cm x 15.24 cm

wood base - from catalog card: 5 in x 3 in; x 12.7 cm x 7.62 cm

cast iron base - from catalog card: 4 in x 6 in; x 10.16 cm x 15.24 cm

cast iron flywheel - from catalog card: 3 1/2 in; x 8.89 cm

overall - from catalog card: 4 3/4 in; x 12.065 cm

Object Name:

toy, electric motor

toy, electric motor, weeden

Date made:

ca 1900

Credit Line:

Gift of Mr. August Mencken

ID Number:

MC.322913

Catalog number:

322913

Accession number:

220719

See more items in:

Work and Industry: Mechanical and Civil Engineering

Engineering Steam Toys and Models

Engineering, Building, and Architecture

Family & Social Life

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a6-81fc-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_847179

Physical Description:

tinplate (overall material)

cast iron (overall material)

nickel plate (overall material)

Measurements:

overall: 6 1/4 in x 6 in x 4 1/4 in; 15.875 cm x 15.24 cm x 10.795 cm

flywheel - from catalog card: 2 1/2 in; x 6.35 cm

tinplate base - from catalog card: 4 in x 6 in; x 10.16 cm x 15.24 cm

Object Name:

toy, electric motor

Date made:

ca 1900

Credit Line:

Gift of Mr. August Mencken

ID Number:

MC.322914

Catalog number:

322914

Accession number:

220719

See more items in:

Work and Industry: Mechanical and Civil Engineering

Engineering Steam Toys and Models

Engineering, Building, and Architecture

Family & Social Life

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a6-6b7c-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_847246

Measurements:

overall: 26 1/8 in x 12 1/8 in x 18 in; 66.3575 cm x 30.7975 cm x 45.72 cm

Object Name:

refrigeration unit

refrigeration unit, domestic

Related Publication:

Frank A. Taylor. Catalog of the Mechanical Collections of the Division of Engineering United States National Museum, Bulletin 173

Credit Line:

Gift of Winslow-Baker-Meyering Corp., Detroit, Michigan

ID Number:

MC.310729

Catalog number:

310729

Accession number:

126271

See more items in:

Work and Industry: Mechanical and Civil Engineering

Work

Industry & Manufacturing

Bulletin 173

Engineering, Building, and Architecture

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a6-acd3-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_845412

Physical Description:

wood (overall material)

brass (overall material)

steel (overall material)

Measurements:

overall: 8 cm x 18.3 cm x 39.4 cm; 3 5/32 in x 7 7/32 in x 15 1/2 in

Object Name:

counter, analog

counter

Date made:

ca 1880

Subject:

Mathematics  Search this

ID Number:

MA.315174

Catalog number:

315174

Accession number:

219145

See more items in:

Medicine and Science: Mathematics

Science & Mathematics

Counters

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a5-0904-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_690544

Measurements:

coil: 1 in x 16 in; 2.54 cm x 40.64 cm

overall: 1 5/8 in x 16 3/4 in x 16 in; 4.1275 cm x 42.545 cm x 40.64 cm

Object Name:

wire sample

Date made:

1862

Credit Line:

from Western Union Corporation

ID Number:

EM.333419

Catalog number:

333419

Accession number:

294351

See more items in:

Work and Industry: Electricity

Transcontinental Railroad

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746ac-cee1-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_1370956

Maker:

McMillan, Edwin M.  Search this

Physical Description:

glass; metal; wood; ceramic; rubber; plastic (overall material)

Measurements:

overall: 5.18 m x 5.24 m x 3.51 m; 17 ft x 17 3/16 ft x 11 1/2 ft

Object Name:

Circular Accelerator, McMillan Synchrotron

circular accelerator, McMillan synchrotron

Subject:

Science & Scientific Instruments  Search this

Credit Line:

Lawrence Berkeley Laboratory, University of California, Berkeley, California

ID Number:

EM.N-09261.01

Catalog number:

N-09261.01

Accession number:

269226

See more items in:

Medicine and Science: Modern Physics

Science & Mathematics

Modern Physics

Energy & Power

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746b2-9bab-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_700137

Maker:

General Electric Company  Search this

Physical Description:

cardboard (box material)

tungsten (bulbs material)

glass (bulbs material)

Measurements:

set of light bulbs: 3 cm x 1 cm; 1 3/16 in x 3/8 in

Object Name:

Light Bulbs, set of

incandescent lamps

Other Terms:

Light Bulbs, set of; Set of Light Bulbs; Lighting Devices; Bayonet, Single Contact; Coiled; Metal

Date made:

From ca. 1930

Date made:

ca 1930

Credit Line:

from M. A. Linett

ID Number:

EM.333872.1

Catalog number:

333872.1

Accession number:

304552

See more items in:

Work and Industry: Electricity

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a5-3d84-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_704683

Maker:

General Electric Company  Search this

Physical Description:

cardboard (box material)

tungsten (bulbs material)

glass (bulbs material)

Measurements:

set of light bulbs: 3 cm x 1 cm; 1 3/16 in x 3/8 in

Object Name:

Light Bulbs, set of

incandescent lamp

Other Terms:

Set of Light Bulbs; Light Bulbs, set of; Lighting Devices; Bayonet, Single Contact; Coiled; Metal

Date made:

From ca. 1930

Date made:

ca 1930

Credit Line:

from M. A. Linett

ID Number:

EM.333872.3

Catalog number:

333872.3

Accession number:

304552

See more items in:

Work and Industry: Electricity

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a5-3d85-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_704684

Associated user:

unknown  Search this

Maker:

Koss Corporation  Search this

Physical Description:

mylar (overall material)

Object Name:

Diaphragm with Voice Coil

headset

Other Terms:

Diaphragm with Voice Coil; Audio Devices

Credit Line:

from Koss Corporation, thru John C. Koss

ID Number:

EM.333812

Catalog number:

333812

Accession number:

304409

See more items in:

Work and Industry: Electricity

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a5-2df1-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_705759

Maker:

Western Union Corporation  Search this

Object Name:

variable inductance

inductance coil

Credit Line:

from Western Union Corporation

ID Number:

EM.332676

Accession number:

294351

294351

Collector/donor number:

74-02

Catalog number:

332676

See more items in:

Work and Industry: Electricity

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a7-3429-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_891622

Maker:

Western Union Corporation  Search this

Object Name:

Coil, Induction

induction coil

Credit Line:

from Western Union Corporation

ID Number:

EM.332792

Accession number:

294351

294351

Catalog number:

332792

See more items in:

Work and Industry: Electricity

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a7-12c5-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_891707

Maker:

Western Union Corporation  Search this

Maker:

A. Gaiffe  Search this

Measurements:

overall: 1 1/2 in x 7 1/2 in x 4 in; 3.81 cm x 19.05 cm x 10.16 cm

Object Name:

Induction Yset

induction set

induction coil

Credit Line:

from Western Union Corporation

ID Number:

EM.333026

Accession number:

294351

294351

Collector/donor number:

100-039

Catalog number:

333026

See more items in:

Work and Industry: Electricity

Data Source:

National Museum of American History

GUID:

http://n2t.net/ark:/65665/ng49ca746a7-025e-704b-e053-15f76fa0b4fa

EDAN-URL:

edanmdm:nmah_891888