midnight
Seeing that their separation must shortly begin , Ayrault tried to assume a cheerful look ; but as Sylvia turned her eyes away they were suspiciously moist . Just one minute before the starting-time Ayrault took Sylvia back to her mother , and , after pressing her hand and having one last long look into her -- or , as he considered them , HIS -- deep-sea eyes , he returned to the Callisto , and was standing at the foot of the telescopic aluminum ladder when his friends arrived . As all baggage and impedimenta bad been sent aboard and properly stowed the day before , the travellers had not to do but climb to and enter by the second-story window . It distressed Bearwarden that the north pole 's exact declination on the 21st day of December , when the axis was most inclined , could not be figured out by the hour at which they were to start , so as to show what change , if any , had already been brought about , but the astronomers were working industriously , and promised that , if it were finished by midnight , they would telegraph the result into space by flash-light code . Raising his hat to his fiancee and his prospective parents-in-law , Ayrault followed them up . To draw in and fold the ladder was but the work of a moment . As the clocks in the neighbouring steeples began to strike eleven , Ayrault touched the switch that would correspond to the throttle of an engine , and the motors began to work at rapidly increasing speed .