eight o’clock
It would afford me a chance of bringing to a kind of test the truth of a surmise , which , more than anything else , had influenced me in attempting this ascension . I had imagined that the habitual endurance of the atmospheric pressure at the surface of the earth was the cause , or nearly so , of the pain attending animal existence at a distance above the surface . Should the kittens be found to suffer uneasiness in an equal degree with their mother , I must consider my theory in fault , but a failure to do so I should look upon as a strong confirmation of my idea . `` By eight o'clock I had actually attained an elevation of seventeen miles above the surface of the earth . Thus it seemed to me evident that my rate of ascent was not only on the increase , but that the progression would have been apparent in a slight degree even had I not discharged the ballast which I did . The pains in my head and ears returned , at intervals , with violence , and I still continued to bleed occasionally at the nose ; but , upon the whole , I suffered much less than might have been expected . I breathed , however , at every moment , with more and more difficulty , and each inhalation was attended with a troublesome spasmodic action of the chest .