text by JORDAN HRUSKA www.markdionsbartramstravels.com MARK DION, Bartram’s Travels – Reconsidered Artist and sometimes explorer Mark Dion is standing in John Bartram’s Gardens in Philadelphia, just before a June thunderstorm. He and artist Dana Sherwood are pressing down on a buoyant peat bog recently made for some of the garden’s new plants. A friend of theirs, Lord Whimsy, is on his way down from the Pine Barrens to deliver cedar water for the thirsty bog, and to celebrate the installation of Dion’s new show, Bartram’s Travels – Reconsidered, on view in the Gardens until December 6, 2008. The Bartrams’ concept for what became the nation’s first-ever botanic garden was to let things grow organically, rather than in the artificial constrictions of British or French garden designs then in vogue. Plants could be encountered serendipitously, as in a forest. George Washington visited John Bartram’s Gardens in 1787. He was reportedly…