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1、LOGOPowerPoint TemplateAdd Your Company SloganYour Site HerevCompetitors You may want to allocate one slide per competitorvStrengths Your strengths relative to competitorsvWeaknesses Your weaknesses relative to competitorRelated DocumentsYOUR SITE HEREContents1. Introduction2. Strategy3. Challengers
2、 Forward4. ConclusionYOUR SITE HEREClick to Edit TitleSub TitleSub TitleYOUR SITE HEREClick to Edit TitleText 2Text 3Text 1Text 4YOUR SITE HEREClick to Edit TitleText 1Text 2Text 3Text 4YOUR SITE HEREABCD1234Click to Edit TitleYOUR SITE HEREChart DocumentsYOUR SITE HEREChart DocumentsYOUR SITE HEREv
3、 During the ice ages, human beings exposed to the colder temperatures of the time would often make their homes in caves. There they found greater comfort and security than they would have in the open.v We still live in caves called houses, again for comfort and security. Virtually no one would willi
4、ngly sleep on the ground under the stars. Is it possible that someday we may seek to add further to our comfort and security by building our houses underground - in new, manmade caves?v It may not seem a palatable suggestion, at first though. We have so many evil associations with the underground. I
5、n 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 g
6、ases.)v 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 Earths crust honeycombed with passages and structures, like a gigantic ant hill.YOUR SITE HEREvFirst, weather w
7、ould no longer be important, since, it is primarily a phenomenon of the atmosphere. Rain, snow, sleet, fog would not trouble the underground world. Even temperature variations are limited to the open surface and would not exist underground. Whether day or night, summer or winter, temperatures in the
8、 underground world remain equable and nearly constant. The 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 saved. The damage done to manmade structures and to human beings by weather would be gone. Tran
9、sportation over local distances would be simplified. (Earthquakes would remain a danger, of course.)v Second, local time would no longer be important. On 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
10、and midnight in yet another. The rhythm of human life therefore varies from place to place. Underground, 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 mans convenience.v The whole world
11、could be on eight-hour shifts, starting and ending on the stroke everywhere, at least as far as business and community endeavors were concerned. This could be important in a freely mobile world. Air transportation over long distances would no longer have entail jet lag. Individuals landing on anothe
12、r coast or another continent would find the society they reached geared to the same time of day as at home.v YOUR SITE HEREvThird, the ecological structure could be stabilized. To a certain extent, mankind encumbers the Earth. It is not only his enormous numbers that take up room; more so, it is all
13、 the structures he builds to house himself and his machines, to make possible his transportation and communication, to offer him rest and recreation. All these things distort the wild, depriving many species of plants and animals of their natural habitat - and sometimes, involuntarily, favoring a fe
14、w, such as rats and roaches.v If the works of man were removed below ground - and, 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 occu
15、pation would be enormously decreased. Indeed, as one imagines the underground world to become increasingly elaborate, one can visualize much of the food supply eventually deriving from hydroponic growth in artificially illuminated areas underground. The Earths surface might be increasingly turned ov
16、er to park and to wilderness, maintained at ecological stability.v Fourth, nature would be closer. It might seem that to withdraw underground is to withdraw from the natural world, but would that be so? Would the withdrawal be more complete than it is now, when so many people work in city buildings
17、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 horizon - plus some limited greenery?v And to get away from the city now? To reach the real countryside? One must travel horizon
18、tally for miles, first across city pavements and then across suburban sprawls.v In an underworld culture, the countryside would be right there, a few hundred yards above the upper level of the cities - wherever you are. The surface would have to be protected from too frequent, or too intense, or too
19、 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 today.v However odd and repulsive underground living may seem at first thought, there are tings to be said for it - and I havent even said them all.YOUR SITE HERELOGOThank You!LOGOAdd Your Company SloganYour Site Here
