I am sorry that I do not know about this family. What I know about the Franke's is that most of them worked at the castle (Castle Barenau). The family that I am familiar with who immigrated were shepherds, lowest on the social standing. This family was descended from the couple Johann Ernst Franke born in 1719, place unknown, died October 31, 1805 in the Engter parish, but he was married to Anna Margaretha Helena Kreyenhagen. She was born in Engter before 1742 and died March 26, 1820 at the Barenau Castle settlement. The were married October 15, 1773 in Venne. One of their children was named Gerdt Henrich, which would alert you to the naming pattern. Perhaps your Johann Gerd was a relative of this family. Did your Franke/Ballmann family come over here?