five o'clock
`` He thinks I shall get enough exercise in hoeing potatoes , '' answered Herbert , with a smile . `` It would n't do him any harm to get exercise in the same way . '' `` The very idea would shock him . '' At five o'clock Mr. Cameron knocked at the door of Mrs. Carter 's cottage . It was opened by Herbert himself . `` Walk in , Mr. Cameron , '' he said , cordially . `` My mother is in the next room . ''