three o'clock
`` And you must go down to the boats every time the clock strikes , to see if they are all right . If they should get adrift , you know , our game would be up . '' `` I 'll see to it . '' `` At three o'clock , you must call the watch that is to relieve you . '' `` Who will that be ? '' `` I , '' volunteered the three other officers of the watches , in concert . `` Ben , you shall relieve him .