Thanks a lot Rose. I do not think that this Henry Jackson is related to me. In the 1880 census, I found a Henry Jackson in Prince William County that seems to be the one that I am looking for. There is a son named Thomas which is the same as my grandfather's. It appears that this family orginated in Loudoun County and then moved to Prince William. Later they moved back to Loudoun. Again thanks for what you discovered.

Hal