The Massachusetts Historical Society is sponsoring a lecture at its headquarters at 1154 Boylston Street in Boston on February 11, beginning at 5:15 pm, by Gretchen Heefner of Northeastern University, with comment by Christopher Capozzola of MIT,, as part of its Environmental History Seminars, entitled Northern Exposure: American Military Engineering in the Arctic Circle. From the late 1940s through the 1960s, U.S. military engineers constructed and maintained a vast, though largely unknown, infrastructure of military facilities throughout the Far North. This talk examines how these engineers explored the Arctic regions, what sorts of information they accumulated about it, and ultimately what happened to that information once it was released from military constraints. Free, but registration requested at www.masshist.org.