twelve o'clock
He made his notes and went to his desk . The next three hours passed without any consciousness of existence save the slow ticking of the astronomical clock which governed the mechanism of the telescope . The rest was merely figures and formulæ , which might amount to the death-sentence of the human race or to an indefinite reprieve . When he got up from his desk he had learnt that the time in which it might be possible to save humanity from a still impending fate had been shortened by twelve days , and that the contact of the comet with the earth 's atmosphere would take place precisely at twelve o'clock , midnight , on the thirtieth of April . Then he went back to the telescope and picked up the comet again . Just as he had got its ominous shape into the centre of the field a score of other shapes drifted swiftly across it , infinitely vaster -- huge winged forms , apparently heading straight for the end of the telescope , and only two or three yards away . His nerves were not perhaps as steady as they would have been without the shock which he had already received , and he shrank back from the eye-piece as though to avoid a coming blow .