10 o'clock
But if anything happens to you I shall know it through Mrs. Stewart , and she will always know where I am and what I am doing . '' `` That is some comfort , '' I returned earnestly . `` What time does the Saturn sail tomorrow ? '' `` At 10 o'clock . But , Madge , you must not come . '' `` I know , '' I returned meekly enough , although a daring plan was just beginning to creep into my brain . `` And I will say good-by now , Jack .