midnight
`` When I am tired I will lie down . '' The skipper nodded and smiled , and went forward again , while , after some minutes ' silence , the professor said softly : `` You are quite right to be doubtful , Yussuf , I mistrust that man . '' `` Yes , '' replied Yussuf in the same tone , `` the Greek dog will bite the hand which fed him if he has a chance , but that chance , effendi , he must not have . '' The hours glided on , and some time , perhaps soon after midnight , the skipper rose again from where he had lain apparently asleep , but really watching the speakers attentively , and coming aft this time with one of his men , the sailor at the helm was changed , and the other went forward to throw himself down as if to sleep . `` Will not the effendi lie down and take his rest now ? '' said the skipper to Yussuf . `` The day will not be very long before it comes , and then it is no longer time to sleep . ''