Edison Patent 223,898 and the Tar-putty Lamp

Historic Edison Collection

Most Famous Lamps in the World

Famous Edison Lamp Collection DISCOVERED After Century in Darkness

On November 4, 1879 a patent was filed by Thomas A. Edison, which was granted as U.S. Patent 223, 898 on January 27, 1880. The lamp drawing from this patent (below) has become an icon symbol of Edison's fundamental electric incandescent lamp. The lamp overlay on the right is Lamp #4 from the Edison Collection, one of the Tar-putty lamps made in accordance with the description in Edison's fundamental lamp patent.

During March and April of 1890, these Tar-putty lamps were made by J. W. Howell as exhibits for his upcoming testimony in the Edison lamp patent infringement law suit. John Howell's famous words, "I hereby produce the lamps," entered his Tar-putty lamps into evidence during the opening of his testimony at 11:00 AM on July 8, 1890. His Tar-putty lamps thus became the key evidence in the world's most famous technology infringement court battle. The Thomas Edison 1880 patent drawing from his U.S. Patent No. 223,898 was the model for this 1890 Tar-putty lamp made by John Howell. See the comparison match-up of the Edison patent drawing and the Howell Tar-putty lamp from the collection shown below.

With John Howell's testimony, the gavel came down, the judge's decision sustained Edison's lamp patent and denied the infringer's defense claim that Edison's patent was invalid. After a decade long contentious battle in court, John Howell's Tar-putty lamps settled the matter once and for all and Edison was victorious at last.

Thomas A. Edison's Patent Drawing - - - John W. Howell's Tar-putty Lamp

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