“The terrestrial globe being thus entirely surrounded by the cometary mass for nearly seven hours, and revolving in this incandescent gas, the air rushing violently toward the center of disturbance, the sea boiling and filling the atmosphere with new vapors, hot showers falling from the sky-cataracts, the storm raging everywhere with electric deflagrations and lightnings, the rolling of thunder heard above the scream of the tempest, the blessed light of former days having been succeeded by the mournful and sickly gleamings of the glowing atmosphere, the whole earth will speedily resound with the funeral knell of universal doom, although the fate of the dwellers in the Antipodes will probably differ from that of the rest of mankind. Instead of being immediately consumed, they will be stifled by the vapors, by the excess of nitrogen—the oxygen having been rapidly abstracted—or poisoned by carbonic-oxide; the fire will afterwards reduce their corpses to ashes, while the inhabitants of Europe and Africa will have been burned alive. “The well-known tendency of carbonic-oxide to absorb oxygen will doubtless prove a sentence of instant death for those farthest from the initial point of the catastrophe. “I have taken as an example the comet of 1811; but I hasten to add that the present one appears to be far less dense.” “Is it absolutely sure?” cried a well-known voice (that of an illustrious member of the chemical society) from one of the boxes. “Is it absolutely sure the comet is composed chiefly of carbonic-oxide? Have not the nitrogen lines also been detected in its spectrum? If it should prove to be protoxide of nitrogen, the consequence of its mixture with our atmosphere might be anæsthesia. Every one would be put to sleep—perhaps forever, if the suspension of the vital functions were to last but a little longer than is the case in our surgical operations. It would be the same if the comet was composed of chloroform or ether. That would be an end calm indeed. “It would be less so if the comet should absorb the nitrogen instead of the oxygen, for this partial or total absorption of nitrogen would bring about, in a few hours, for all the inhabitants of the earth—for men and women, for the young and the aged—a change of temperament, involving at first nothing disagreeable—a charming sobriety, then gayety, followed by universal joy, a feverish exultation, finally delirium and madness, terminating, in all probability, by the sudden death of every human being in the apotheosis of a wild saturnalia, an unheard-of frenzy of the senses. Would that death be a sad one?”