I have never done research in DC although I hope to make a trip sometime this coming year. I lived in Bethesda and Rockville for a short period of time but unfortunately was not doing genealogy at that time. My 2X ggrandfather Benjamin F. Herdman (b. 1823 in Delaware) moved to DC in the 1870s. He lived there until his death in 1907. His wife and some children are buried at Oak Hill Cemetery, the last family member Jacob D. Herdman died in 1927. Have found death records, but no wills. Need to get back there! Joy Napa, CA