. Collection of United States patents granted to Thomas A. Edison, 1869-1884 . 128,608 United States Patent Office, — THOMAS A. EDISON, OF NEWABK, NEW IN PRINTING-TELEGRAPH INSTRUMENTS. Specification forming part of Letters Patent No. 128,608, dated July 2, 1872. To all whom it may concern: Be it known that I, Thomas A. Edison, ofNewark, in the county of Essex and State ofNew Jersey, have invented and made a newand useful Improvement in Printing-Tele-graphs, and the following is declared to he acorrect description thereof. Printing-telegraphs have been constructedto work upo


. Collection of United States patents granted to Thomas A. Edison, 1869-1884 . 128,608 United States Patent Office, — THOMAS A. EDISON, OF NEWABK, NEW IN PRINTING-TELEGRAPH INSTRUMENTS. Specification forming part of Letters Patent No. 128,608, dated July 2, 1872. To all whom it may concern: Be it known that I, Thomas A. Edison, ofNewark, in the county of Essex and State ofNew Jersey, have invented and made a newand useful Improvement in Printing-Tele-graphs, and the following is declared to he acorrect description thereof. Printing-telegraphs have been constructedto work upon a single wire by means of twoelectro-magnets and one polarized magnet, socombined with each other that a current of onepolarity is made to act upon one electro-mag-net and an opposite current upon the othermagnet by arranging cut-offs upon the electro-magnets and rendering them active or inact-ive, as the case may be, by the polarized mag-net. My present invention consists of a com-pound electro-magnet, constructed in such amanner that when a current of one polarityente


Size: 1259px × 1985px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ., boo, bookcentury1800, booksubjectinventions, booksubjecttelephone