One of Philadelphia's and the nation's leading collectors of African American artifacts has turned over historic artifacts from abolitionist Harriet Tubman to a new museum scheduled to open in 2015. Charles Blockson, curator emeritus of the Charles Blockson Afro-American collection at Temple University, received 39 personal items from the estate of Underground Railroad Conductor Harriet Tubman from Tubman's great niece, who willed them to Blockson two years ago because she believed that he, Blockson says, would know what to do with them.