British steam tanker Cowrie visited the Black Se according to a letter of the German naval attaché at Istanbul dated 20 January 1940

In his letter dated Istanbul, 20 January 1940 No. 650 g1. reported the German naval attaché to the Oberkommando der Wehrmacht Abteilung Ausland on 11 January 1940 the passing of the British steam tanker Cowrie with 1 gun on the stern. Black painted, grey command bridge, yellow funnel and yellow masts.

Source

Bundesarchiv. German Marineattaché for , Greece, Romania and Bulgaria 1939-1941. RM 12-II/459.