Question: William F Romain led a team in an investigation a effigy mound in Adams County, Ohio, that is how long?
Sentence (from "Serpent Mound"): The Serpent Mound of Ohio was first reported from surveys by Ephraim Squire and Edwin Davis in their historic volume "Ancient Monuments of the Mississippi Valley", published in 1848 by the newly founded Smithsonian Museum.
Relevant evidence: No