The Smithsonian’s National Museum of American History opened Abraham Lincoln’s pocket watch this past March, and discovered a secretly engraved message that turned an unsubstantiated family story into a confirmed historical event.

Jonathan Dillon, a watchmaker who immigrated to Washington, D.C. from Waterford, Ireland, repaired Lincoln’s gold watch in 1861 and engraved the following words on the underside of the watch movement:

“Jonathan Dillon April 13- 1861 Fort Sumpter was attacked by the rebels on the above date.

J Dillon.

April 13-1861 Washington thank God we have a government. Jonth Dillon.”

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Dillon passed down the story of engraving his pro-Union sentiments in Lincoln’s timepiece to his descendants, and his great-great-grandson Douglas Stiles, a lawyer from Illinois, recently discovered an article in The New York Times from April 1906 in which the story is recounted.

Then 84, Dillon told of writing the inscription after the owner of M.W. Galt & Company, the Pennsylvania Avenue watch shop in Washington, D.C., rushed upstairs to announce that the first shot had been fired and the war was underway.

“At the moment I had in my hand Abraham Lincoln’s watch, which I had been repairing,” Dillon recounted.

The watch was bequeathed to the Smithsonian by a great-grandson of Lincoln’s in  1958, but after Stiles brought the curators’ attention to the 1906 article, the museum enlisted the help of George Thomas, a master watchmaker from Maryland, who opened the watch using magnifying glasses, a strong light and minuscule instruments in an event open to the public. 

“It’s a moment of discovery, and you can only discover things once. We wanted to share it,” said Harry Rubenstein, curator of the Smithsonian’s “Abraham Lincoln: An Extraordinary Life” exhibition.

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In the 1906 article, Dillon recalled his inscription as reading, “The first gun is fired. Slavery is dead. Thank God we have a President who at least will try.” This description was not entirely accurate, but museum director Brent D. Glass was unsurprised that Dillon did not mention slavery in the actual engraving.

“In 1861 the preservation of the union was the key issue, and the abolition of slavery came later,” said Glass. Dillon’s inscription also misdates the opening shot of the Civil War, which was actually fired on April 12, and misspells Sumter. Still, the message is clear.

“It has that hopeful sound that the union will hold together, the country will go on,” said Rubenstein. “That Lincoln carried this hopeful message in his pocket unbeknownst to him – it casts you back.”

Two other inscriptions were also found on the back of the watch movement. One reads “LE Grofs Sept 1864 Wash DC” and was probably added by another watchmaker doing a repair. 

The other, “Jeff Davis,” may have been intended as a rejoinder to Dillon’s pro-Union inscriptions, as Jefferson Davis was the president of the rebel Confederacy.

According to Thomas, the timepiece was made in Liverpool but the case was crafted in America. He said that the watch, reportedly the only watch that Lincoln owned, was in perfect condition and looked as if it had not been worn very much. While the watch is unable to be wound after hundreds of years of no use, it will be reassembled and available for viewing at the museum with a photograph and transcription of the engraving.

Stiles claimed that the story of Dillon’s “graffitti” had been told to him in the 1970’s by a great-uncle, and his attention returned to it last year when an Irish cousin recounted the story as well. The revelation of the inscription lends a new credibility to generational tales and emphasizes the importance of oral history, persistent as it is in the Irish-American tradition. 

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