Detail
Type Ml. - Martins Mühle is a Mühle (Mill).
Kr Offenbach - The Kreis for Martins Mühle is Offenbach. A Kreis is a government district (similar to a U.S. county).
See Langen B. Darmstadt - A See notation means the entry is dependent on another entry. In this case, Martins Mühle is dependent on Langen B. Darmstadt, which should be consulted for additional information.