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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