Lincoln at Gettysburg on 19 Nov. 1863

In the realm of obviousness (and KSR v. Teleflex), things that might seem obvious to one person are not necessarily obvious to another. Take the location of "where" Abraham Lincoln gave the Gettysburg Address. One might think that that one was nailed down a long time ago. Lots of reporters and politicians were there. Photographs, too. Sadly, the place the NPS has marked as the location isn't the correct one. Kathleen Georg [Harrison] took two photographs of the event, from different perspectives, and figured out the location is in the Evergreen Cemetery. She wrote up her findings in (among other places) Civil War Times Illustrated in the 1980's . There's little debate she got it right.

In an article titled Disproving many historical 'facts', the Washington Times in April 2008 discusses the matter. [A new marker has been authorized to be placed on the Park Service side of the fence. ]

Was what Georg-Harrison did obvious? Some might say so. Some might not. Did it lead to an unexpected result? Yes, relative to conventional wisdom. Did it change what the average visitor to Gettysburg sees. No. Did Spencer's rifle help Custer at Gettysburg in 1863? Yes. Did it help Custer at Little Big Horn in 1876? No.

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Separately, note a site on science confirms the obvious