2:45 a.m.
`` A fat lot of good I am ! '' `` My dear chap , you ca n't possibly watch the whole coast all night and every night . This time the signals were seen from the sea as a matter of fact . But you can note the night , and also the hour , which was 2:45 a.m. , G.M.T. , as near as I can make out from the report . By the way , you had better set your watch by mine now while we remember . Possibly you may be able to discover who was out at that hour night before last . '' `` I may , but it 's a thousand to one against it .