With his 1893 Map of the Square and Stationary Earth, Orlando Ferguson made visual his emphatic claim that the earth was flat. One hundred and eighteen years later, one of the last remaining copies is being donated to the Library of Congress, which inexplicably does not already own a copy of this dotty gem. Only one other copy is known to exist. More (including a high-resolution scan) at The History Blog. Via io9 and MapHist.