seven o'clock
The horseflies were black and green in color , and a bite from one of them made Captain Zoss utter a mighty yell of pain . `` It was like the stab of a dagger ! '' he declared afterwards , and so angry did the bite become , and so painful , that the doctor was called upon to treat it with a soothing lotion . It was after seven o'clock , but still daylight , when Dr. Barwaithe raised his hand for the others to become silent . `` Listen ! '' he said . `` I think I heard a steamboat whistle .