2024-08-132024-08-132012-01-12https://hdl.handle.net/10929/139587Edison worked on automatic telegraphs between 1870 and 1874. He first developed an improved perforator with a keyboard similar to that of a typewriter that operated at about 35 words per minute. In 1874 he began to work on a multiplex telegraphic system for Western Union, ultimately developing a quadruplex telegraph, which could send two messages simultaneously in both directions.Original file name 6797630883_f8b131c8c9_o.jpeg3911 x 1999Each photograph within this collection is protected by copyright and/or related rights. Therefore, these photos may only be used in a way that is permitted by copyright and related rights legislation. The following terms of use for State Library patrons shall apply. 1. Educational Institution/student use is permitted as long as such usage adheres to all copyright and related rights legislation. In these instances, these photographs may only be used for educational or historical purposes. 2. Non-Commercial use is permitted without permission from the rights holder, as long as such use adheres to all copyright and related right legislation. 3. Under no circumstances may these photographs be used for commercial purposes without the direct permission of the rights-holder. 4. Under no circumstances may these photographs be used for political purposes. 5. Users must always give appropriate credit to the photographer. The credit may not in any way suggest the right's holder endorses the user or their use of the photographs. 6. Photographs may be copied or redistributed in any medium or format as long as such use does not violate copyright and related rights legislation. 7. Users may remix, transform, and rebuild upon the original photographs as long as it does not violate copyright and related rights legislation.Edison's TelegraphThomas Edison's Factory. Edison FactoryThe FactoryEdison Research FacilityEdison's Manufacturing FacilityThomas EdisonEdisonNational Historical ParkNPSNational Park ServiceNational Historical SiteIndustrial RevolutionU.S. Historic districtU.S. National Register of Historic PlacesWest OrangeEssex CountyNew JerseyNJJerseyThe Garden State