Like the typewriter and the light bulb, the heterosexual was invented in the 1860s and swiftly and permanently transformed Western culture. Writer and historian Hanne Blank reads from her lively, timely new book “Straight: The Surprisingly Short History of Heterosexuality.” Blank’s work has been featured everywhere from “Out” to “Penthouse.” Her previous books are “Big Big Love” and “Virgin: The Untouched History.”