The article describes the medical aspects on board the danish naval vessels "Gefion", "Chr. den VIII", "Geiser" and "Hekla" as well as other assignments which demanded special abilities of the naval doctors and the head doctor at "Christians Plejehjem" under and after the sea battle at Eckernförde the 5th of April 1849. The conditions for the wounded on board "Gefion" is described - the cabins, the pharmacy etc. The diagnoses of the wounded and their treatment, especially the surgical interventions are accounted for as well as the lesions of the dead and the arrangements on shore after the battle. The article is based on the preserved logbooks and sick records etc. from the naval vessels and on the records from "Bibliotek for Laeger" 1850 by chief surgeon Chr. Wilken Hornemann and the reports by chief surgeon G. Courtlaender from the 20th May 1849 at "the Maritime Inquiry" of the 1st of October 1849.