Communications

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  Cartridge Wire Recorder

  Description (Brief)

  This model MI-12525 RCA wire recorder shows one answer to a major problem of using steel wire to record sound. The recording wire is wound into a cartridge. The user simply inserts the cartridge into the recorder and can quickly begin using the machine. This machine was designed for use in office dictation around 1948.

  Early magnetic recorders used steel wire or steel bands as a recording medium instead of plastic tape. Steel wire was fragile and tangled easily. Threading a recording machine took a certain amount of finesse and the wire could easily break if mishandled.

  Location

  Currently not on view

  date made

  ca 1948

  maker

  Radio Corporation of America

  ID Number

  2002.0034.01

  accession number

  2002.0034

  catalog number

  2002.0034.01

  Data Source

  National Museum of American History

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  Railroad Hand-Signal Lantern, 1870s-80s

  Description

  This railroad hand-signal kerosene lantern was manufactured by the Adams & Westlake Company of Chicago, Illinois around 1870. Adlake was a major equipment supplier to railroads during the Westward expansion. The lantern is made of metal with a wire frame protecting the glass globe. The globe has the frosted name “J.H. Barrelle” in the center, surrounded by frosted glass floral designs. J.H. Barrelle was an agent for the Milwaukee Railroad, living in South Dakota in 1881, who likely used this hand-signal lantern.

  Before the advent of portable two way radios, train crews communicated via hand signals during the day, and lantern signals during periods of low visibility or at night. Specific motions of the lantern convey precise instructions such as “Clear to Depart;" "Move the train Forward;" "Move the train Backward;" "Slow Down;" "Slow Down Further;" or "Stop and Remain Stopped."

  Location

  Currently not on view

  date made

  1970-1989

  maker

  Adams & Westlake Company

  ID Number

  TR.322916

  catalog number

  322916

  accession number

  249870

  Data Source

  National Museum of American History

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  Ship Model, Santa Maria

  Description

  In 1492, Christopher Columbus sailed a small fleet of three small ships west from Spain across the Atlantic Ocean, hoping to find a shorter route to the riches of Asia. Before his voyages, Chinese and Indian luxuries for European markets were transported over the long and hazardous overland route through Arabia.

  The three-masted vessel Santa Maria was the largest of Columbus’s expeditionary vessels and his flagship. Measuring around 70 feet in length, it carried a crew of 40 men. The Santa Maria and Columbus’s other fleet members the Niña and the Pinta were older ships used for coastal trading rather than vessels designed for ocean crossings. Nine weeks after the little fleet left Spain, land was sighted in the Caribbean on 12 October 1492, but exactly which island Columbus’s crew first spotted remains disputed.

  The fleet went on to explore the north coasts of the islands of Cuba and Hispaniola (now Haiti). On Christmas Day 1492, the Santa Maria ran aground on a reef off Hispaniola and was declared a total loss. The ship’s timbers were salvaged and used to build a small fort on shore. Fortunately for Columbus, he was able to return to Spain on the Niña.

  Instead of Asia, Columbus had landed in the Caribbean islands on his first voyage. Although they were already inhabited, he claimed them for Spain. Columbus made three more voyages to the western hemisphere between 1493 and 1504.

  Waves of conquerors and colonists—both free and enslaved—followed. What was a triumph for Spain became a catastrophe for native peoples. New livestock, plants, diseases, and beliefs unsettled centuries-old communities and ecosystems, changing and destroying the lives of millions.

  This model was built at the Museo Maritimo de Barcelona, Spain, under the supervision of museum director Jose Maria Martinez-Hidalgo y Teran, who published a book on the Santa Maria in 1964.

  Date made

  1965

  ID Number

  TR.325800

  catalog number

  325800

  accession number

  260040

  Data Source

  National Museum of American History

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  Navigational Bell Buoy

  Description

  Unlike car drivers on land, navigators at sea have no road signs to indicate speed limits, dangers, or routes. Navigational buoys are floating objects anchored to the bottom that serve as aids to navigation. Their distinctive shapes, colors, and other markings provide information indicating their purpose and how to navigate around them.

  The placement and maintenance of navigational buoys are essential to shipping, since they often provide the only guidance for channel locations, shoals, reefs, and other hazards. If damaged by collisions, extinguished, or broken loose from their moorings, the Coast Guard will repair, replace, refuel, or relocate the failed buoy.

  Designated an 8X20 LBR, this particular type of buoy was used by the U.S. Coast Guard Lighthouse Service on the East Coast from around 1930 until the early 1950s. It measures 8 feet in width and 20 feet high, and the letters mean Lighted, Bell, and Radar Reflector. It originally weighed ca. 15,600 pounds, including the 225-lb bell. The bottom of this example was removed to fit into the gallery.

  It was designed to be deployed in shallow, protected coastal waters and could be seen about two miles away in daylight. The light on the top was powered by batteries stored under the round hatches in the large bottom compartment. The bell was rung by the rocking of the buoy in the waves.

  ID Number

  TR.336771

  accession number

  1978.2285

  catalog number

  336771

  Data Source

  National Museum of American History

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  Telegraph Sounder

  Description (Brief)

  Telegraph sounders convert electrical pulses into audible sounds and are used to receive Morse code messages. The message travels as a series of electrical pulses through a wire. Short pulses make a dot, slightly longer pulses make a dash. The sequence of dots and dashes represent letters and numbers. The pulses energize the sounder’s electromagnets which move a lever-arm. The arm makes a loud “click” when it strikes a crossbar and the operator translates the pattern of sounds into the original language. This very early sounder, made only a dozen years after Morse's "What Hath God Wrought" message, is ornate and features a marble base plate.

  Location

  Currently not on view

  date made

  ca 1856

  maker

  Clark, James J.

  ID Number

  EM.181424

  catalog number

  181424

  accession number

  31652

  Data Source

  National Museum of American History

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  Telegraph Sounder

  Description (Brief)

  Telegraph sounders convert electrical pulses into audible sounds and are used to receive Morse code messages. The message travels as a series of electrical pulses through a wire. Short pulses make a dot, slightly longer pulses make a dash. The sequence of dots and dashes represent letters and numbers. The pulses energize the sounder’s electromagnets which move a lever-arm. The arm makes a loud “click” when it strikes a crossbar and the operator translates the pattern of sounds into the original language. According to Western Union this “crude” sounder was not only a practical instrument but saw actual service. “It was improvised by an operator who had at hand no other means of providing himself with desired apparatus to complete his office equipment.”

  Location

  Currently not on view

  ID Number

  EM.230789

  catalog number

  230789

  accession number

  43225

  Data Source

  National Museum of American History

• Pond's Wooden Telegraph Insulator

  Location

  Currently not on view

  date made

  ca 1875

  maker

  Pond, Chester H.

  Kenosha Insulator Company

  ID Number

  EM.231785.2

  catalog number

  231785.2

  accession number

  43532

  Data Source

  National Museum of American History

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  Elisha Gray patent model telegraph repeater

  Description

  Telegraph repeaters amplified electrical signals in a telegraph line. Telegraph messages traveled as a series of electrical pulses through a wire from a transmitter to a receiver. Short pulses made a dot, slightly longer pulses a dash. The pulses faded in strength as they traveled through the wire, limiting the distance a message could travel. Repeaters remedied that problem by detecting a weak signal and using a local power source to re-energize and re-transmit the signal down the line.

  This working model was submitted to the U.S. Patent Office by inventor Elisha Gray of Chicago along with his patent application. On 16 May 1871, he received patent #114938 for his "Improvement in Telegraph-Repeaters." Gray's idea, called a "shunt repeater," transferred or "shunted" some of the electrical current to an extra pair of small electromagnets to allow for automatic operation of the repeater. Our records also associate this object with telegraph inventor Charles Haskins although the association is unclear. While Haskins did patent his own repeater whose action was described at the time as "similar to Gray's," patent 114938 was issued to Gray alone and was not assigned to anyone else.

  Location

  Currently not on view

  date made

  1871

  maker

  Gray, Elisha

  ID Number

  EM.251262

  catalog number

  251262

  accession number

  48865

  patent number

  114938

  Data Source

  National Museum of American History

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  Lindsey telegraph repeater patent model

  Description

  Telegraph repeaters amplified electrical signals in a telegraph line. Telegraph messages traveled as a series of electrical pulses through a wire from a transmitter to a receiver. Short pulses made a dot, slightly longer pulses a dash. The pulses faded in strength as they traveled through the wire, limiting the distance a message could travel. Repeaters remedied that problem by detecting a weak signal and using a local power source to re-energize and re-transmit the signal down the line.

  In July 1872, inventor Landy T. Lindsey of Tennessee submitted this model along with his application for a U.S. patent. In 1873 he received patent #136251 for an "Improvement in Telegraph-Repeaters," in which he disclosed a circuit design "simple, reliable and void of many of the mechanical auxiliaries heretofore used" in automatic repeaters. He did not manufacture all the parts of his model however. The telegraph keys were made by L. G. Tillotson & Co., and the sounders and relays have the stamp of James J. Clark of Philadelphia. Lindsey simply arranged the manufactured components in a novel circuit to accomplish his invention.

  Location

  Currently not on view

  date made

  1873

  maker

  Clark, James J.

  L. G. Tillotson & Co.

  Lindsey, Landy T.

  ID Number

  EM.251264

  catalog number

  251264

  patent number

  136251

  accession number

  48865

  Data Source

  National Museum of American History

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  Telegraph Sounder and Speaking Telephone

  Description (Brief)

  Telegraph sounders convert electrical pulses into audible sounds and are used to receive Morse code messages. The message travels as a series of electrical pulses through a wire. Short pulses make a dot, slightly longer pulses make a dash. The sequence of dots and dashes represent letters and numbers. The pulses energize the sounder’s electromagnets which move a lever-arm. The arm makes a loud “click” when it strikes a crossbar and the operator translates the pattern of sounds into the original language. Inventor Amos Dolbear, known for his early experiments in telephony, made this patent model of a combination device that worked both as a telegraph sounder and a telephone receiver.

  Location

  Currently not on view

  date made

  1879

  maker

  Dolbear, Amos E.

  ID Number

  EM.252631

  catalog number

  252631

  accession number

  49064

  patent number

  220205

  Data Source

  National Museum of American History

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