10 a.m.
It contained two items of bad news . In the first place , I heard for the first time of the tragedy of Heinrich Baumer 's boat , and to my astonishment Fritz tells me that Rosa and another girl were in her when she was lost ! It appears that she was to go out for a couple of hours ' diving off the port as a matter of routine after her two months ' overhaul . She went out at 10 a.m. , and was sighted from the signal station at the end of the mole at 11.30 , when almost immediately afterwards there was an explosion and she disappeared . Motor-boats were quickly on the scene , but only debris came to the surface . Divers were sent down , and reported that she was in ten metres of water completely shattered . It is assumed , for lack of other explanation , that she struck a chance drifting mine which was moving down the coast on the tide .