A Thousand Degrees below Zero by Murray Leinster

New York was frightened, and the newspapers as they appeared did not allay that fear. The conservative _Tribunal_ ran a scare head: HAS THE GLACIAL AGE COME AGAIN? and printed underneath a résumé of the phenomena up to the time of going to press -- which did not include the appearance of the black flyer -- with an interview from a prominent scientist. An enterprising reporter had routed the worthy gentleman out of bed and rushed him to the scene of the expanding ice cake in a fast motor boat, taking down in shorthand his comments on the matter. The scientist had been much puzzled, but spoke at length nevertheless. He said in part:

Has the glacial age come again? I do not know. I can only say that we have no certain knowledge of the original cause of the glacial period and we cannot say definitely that it did not begin in precisely this fashion. We have volcanos which radiate incredible quantities of heat to the country surrounding them. No phenomenon like this has occurred before, but it may be that some unknown cause may bring to the surface a condition the antithesis of a volcano, which, instead of radiating heat, will bring on local glacierlike conditions. One might go farther and suggest that the earth may alternate between periods of volcanic activity, during which it is warm and conditions are favorable for habitation and growth, and periods of this new antivolcanic activity during which frigidity is normal, and mankind may be forced to take refuge in the tropic zones. Still, I cannot say definitely.