about midnight
Here they were again treated to the spectacle of a superb desert sunset . This leisurely mode of progression , however , was beginning to pall somewhat upon the travellers , or rather , upon the male portion of them . It was altogether too uneventful for their taste ; moreover , their appetite for sport had been whetted afresh by their experience among the rocks , and as they sat at dinner that night they unanimously decided that , as the climate seemed to agree thoroughly with little Ida -- who was growing better and stronger every day -- they would waste no further time in dawdling , but would forthwith make the best of their way to the spot where , on their previous cruise , they had seen that wonderful animal the unicorn , almost precisely the creature depicted in the royal arms of Great Britain , and endeavour to secure a specimen or two . Accordingly , after spending a very enjoyable evening in the music-saloon , the ladies retired to rest about midnight , while the men , producing their large-scale map of Africa , carefully laid down upon it the course , and measured off the distance necessary to carry them to the point which they desired to reach . This ascertained , Mildmay -- who usually performed the duties of navigator -- ascended to the pilot-house and , injecting a sufficient quantity of vapour into the air-chambers to produce the required vacuum , caused the ship to rise to a height of ten thousand feet into the calm belt , sent the engines ahead , gradually raising their speed to the maximum , and meanwhile heading the ship upon her proper course . Then he returned below , and reported to Sir Reginald what he had done , and all hands retired to their respective cabins for the night , quite confident , from past experience , of the ship 's ability to take care of herself during the hours of darkness . They all slept well , as was usual with them while enjoying this delightful , untrammelled , open-air existence ; but the eager enthusiasm of the scientist and explorer caused the professor to be astir with the first streak of dawn , and rising quietly , he made his way noiselessly , in pyjamas and slippered feet , to the pilot-house , out of the windows of which he peered eagerly about him .