six o'clock
The Doctor was upon his favorite theme -- the propagandism of the peculiar system of medicine of which he was so faithful and successful a practitioner -- and they had left the city far behind them , when he again paid attention to the rapidly changing scenery below . The wind had increased to a strong gale , and they were crossing the full length of Pennsylvania at astounding speed . They passed over the mountain ranges of the eastern part of the state , with as little concern or thought as if they had been level plain or water . So greatly had their speed accelerated , that by six o'clock the smoke of the great city was discernible immediately before them . The beautiful Hudson looked like a silver ribbon trending away to the north . New York bay with its shipping from all quarters of the earth , Liberty Lighting the World , the suspension bridge , and the tall buildings of the city , were all distinctly seen by the voyagers at a great distance . The booming of cannon announced to our friends that they had been sighted by those upon the lookout for them .