Over the last four decades, the Black photographer Dawoud Bey has documented his community’s hardships, troubles, and triumphs through merciless portraiture. In his new series, “For Night Coming Tenderly, Black,” which takes its title from the Dream Variations by Harlem poet Langston Hughes, Bey turns his focus to the Underground Railroad. He snaps dilapidated houses and patches of land in Cleveland and Ohio, rumored to have once been the stations and safe houses that harbored escaping slaves. Alongside the piercing black-and-white images, William Johnson’s 1944 painting Swing Low, Sweet Chariot presents a surreal image of heavenly freedom north of the Ohio River. —E.C.