Collection of United States patents granted to Thomas A. Edison, 1869-1884 (1869)
Edison, Thomas A. (Thomas Alva), 1847-1931, Peters, N. (Norris), lithographer, Hammer, William Joseph, 1858-1934, former owner. DSI, Edison, Thomas A. (Thomas Alva), 1847-1931, inscriber. DSI, United States. Patent Office · Washington, D.C. : U.S. Patent Office · leaf 491
I T. A. EDISON. DUPLEX TELEGRAPH.No. 178,221. Patented May 30, 1876. … N. PETERS; PHOTO-LITHOGRAPHER. WASHINGTON, D C. United States Patent Office THOMAS A. EDISON, OF NEWARK, NEW JEESEY, ASSIGNOR OF ONE-HALFHIS RIGHT TO GEORGE B. PRESOOTT, OF NEW YORK CITY. IMPROVEMENT IN DUPLEX TELEGRAPHS. Specification forming part of Letters Patent No. 178,221, dated May 30,1876;…
Trade catalogs · Patents · Edison, Thomas A. (Thomas Alva), 1847-1931 · Inventions · Telegraph · Electric machinery · Electric apparatus and appliances · Phonograph · Telephone · Motors
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