midnight
` Good-bye , ' said I . He shook hands and vanished in the night . Sometimes I ask myself whether I had ever really seen him -- whether it was possible to meet such a phenomenon ! ... `` When I woke up shortly after midnight his warning came to my mind with its hint of danger that seemed , in the starred darkness , real enough to make me get up for the purpose of having a look round . On the hill a big fire burned , illuminating fitfully a crooked corner of the station-house . One of the agents with a picket of a few of our blacks , armed for the purpose , was keeping guard over the ivory ; but deep within the forest , red gleams that wavered , that seemed to sink and rise from the ground amongst confused columnar shapes of intense blackness , showed the exact position of the camp where Mr. Kurtz 's adorers were keeping their uneasy vigil . The monotonous beating of a big drum filled the air with muffled shocks and a lingering vibration .