Modern Marvels - Season 9 Episode 21 Fire and Ice.

Who could imagine life without our "man-made weather"? On cold winter nights and hot summer days, we are forever grateful to the visionaries who took two basic elements–fire and ice–and turned them into true modern marvels. Fire warmed the caves and primitive dwellings of mankind for centuries, yet the technology of keeping cool lagged far behind as we learn in this chronicle of heating and air conditioning that covers advancements from the home and industry to outer space and beyond!