midnight before
Once or twice Mark was sent for to make some adjustment to the machinery , but the apparatus , for the most part , was automatic , and needed little attention . The professor , as well as the others , were all impatience for the promised visit of the mate . Still they felt he would not come until night . In fact it was long past midnight before Mark , Jack and the professor , who were anxiously listening , heard the three raps , then two , then three more . Mark quickly opened the door , and the mate stepped inside , holding his finger to his lips as a sign of caution . Old Andy , Washington , Bill and Tom had fallen asleep . `` I have only time for a few words , '' the mate said .