"The printing company had to run each page of [a] magazine through the press once for each color on the page. Sometimes one color was printed one day, and another color the next. The problem was that paper would absorb moisture from the sticky Brooklyn air and expand by a fraction of an inch, enough so that the colors would not line up properly."
Carrier's solution was to run air through perforated pipes filled with cold water; it also involved fans, ducts, and heaters. (Later, he would add refrigeration.) His system would spread; a magazine called him "a Johnny Icicle planting the seeds of climate control all across America."
Air conditioning radically changed the world: it made computers possible, as well as living in Singapore or the Sun Belt. It also produced cities' worth of people so unaccustomed to experiencing heat that they can't live without air conditioning (I write, from a room without even a fan!). Though that was also true in 1902: a week before Carrier signed his blueprints, seven New Yorkers had died from the heat.
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