sentences:  She initially patrolled the line between Dornbusch and Møn, and was briefly assigned to the Detached Division under "KAdm" Ehler Behring.She took part in a sortie into the Gulf of Finland that occurred from 3 to 9 September under the direction of Prince Heinrich of Prussia, the supreme commander of naval forces in the Baltic.While on the operation on 8 September, "Undine" suffered a machinery breakdown that forced her to return to Danzig and then Kiel for repairs.