【正文】 ort and security than they would have in the still live in caves called houses, again for fort and no one would willingly sleep on the ground under the it possible that someday we may seek to add further to our fort and security by building our houses undergroundin new, manmade caves?It may not seem a palatable suggestion, at first have so many evil associations with the our myths and legends, the underground is the realm of evil spirits and of the dead, and is often the location of an afterlife of torment.(This may be because dead bodies are buried underground, and because volcanic eruptions make the underground appear to be a hellish place of fire and noxious gases.)Yet there are advantages to underground life, too, and something to be said for imagining whole cities, even mankind generally, moving downward。of having the outermost mile of the Earth39。s crust honeybed with passages and structures, like a gigantic ant , weather would no longer be important, since, it is primarily a phenomenon of the , snow, sleet, fog would not trouble the underground temperature variations are limited to the open surface and would not exist day or night, summer or winter, temperatures in the underground world remain equable and nearly vast amounts of energy now expended in warming our surface surroundings when they are too cold, and cooling them when they are too warm, could be damage done to manmade structures and to human beings by weather would be over local distances would be simplified.(Earthquakes would remain a danger, of course.)Second, local time would no longer be the surface, the tyranny of day and night cannot be avoided, and when it is morning in one place, it is noon in another, evening in still another and midnight in yet rhythm of human life therefore varies from place to , where there is no externally produced day, but only perpetual darkness, it would be arificial lighting that produces the day and this could be adjusted to suit man39。s whole world could be on eighthour shifts, starting and ending on the stroke everywhere, at least as far as business and munity endeavors were could be important in a freely mobile transportation over long distances would no longer have entail “jet lag.” Individuals landing on another coast or another continent would find the society they reached geared to the same time of day as at , the ecological structure could be a certain extent, mankind encumbers the is not only his enormous numbers that take up room。more so, it is all the structures he builds to house himself and his machines, to make possible his transportation and munication, to offer him rest and these things distort the wild, depriving many species of plants and animals of their natural habitatand sometimes, involuntarily, favoring a few, such as ratsand the works of man were removed below groundand, mind you, below the level of the natural world of the burrowing animals —— man would still occupy the surface with his farms, his forestry, his observation towers, his air terminals and so on, but the extent of that occupation would be enormously , as one imagines the underground world to bee increasingly elaborate, one can visualize much of the food supply eventually deriving from hydroponic growth in artificially illuminated areas Earth39。s surface might be increasingly turned over to park and to wilderness, maintained at ecological , nature would be might seem that to withdraw underground is to withdraw from the natural world, but would that be so? Would the withdrawal be more plete than it is now, when so many people work in city buildings that are often windowless and artificially conditioned? Even where there are windows, what is the prospect one views(if one bothers to)but sun, sky, and buildings to the horizonplus some limited greenery?And to get away from the city now? To reach the real countryside? One must travel horizontally for miles, first across city pavements and then across suburban an underworld culture, the countryside would be right there, a few hundred yards above the upper level of the citieswherever you surface would have to be protected from too frequent, or too intense, or too careless visiting, but however carefully restricted the upward trips might be, the chances are that the dwellers of the new caves would see more greenery, under ecologically healthier conditions, than dwellers of surface cities to odd and repulsive underground living may seem at first thought, there are tings to be said for itand I haven39。t even said them all.