Air conditioning: On a hot day, some people feel like they would not survive without it. It does not only refer to controlling the temperature of an indoor area (cooling), though. It also refers to controlling the humidity and sometimes even the purity of the air in an interior. When you are cruising down the street on a blistering day with the AC cranked up or freezing in a frigid movie theater watching the latest blockbuster, do you ever wonder who came up with the idea of air conditioning? It may have started earlier than you think.
The Ancient Romans invented sewers, public baths, and pottery which prove how innovative their society was. They also came up with the idea of circulating aqueduct water through the walls of houses to cool them. The Medieval Persians used a complex system of cisterns and wind towers to cool their civilization. A cistern was a large open pool in a central courtyard that collects rain water. The wind tower had windows that caught wind and internal vanes to direct the airflow down to the buildings, over the cistern and out through a downwind cooling tower. When the water in the cistern evaporated, it cooled the air in the building.
The process we currently think of as air conditioning got its start a little later. In 1820, Michael Faraday, an English chemist and physicist, discovered that compressing and liquefying ammonia could chill air when the liquefied ammonia was allowed to evaporate. In 1842, John Gorrie, a physician in the United States, used compressor technology to create ice. He dreamed of using his ice-making machine to regulate the temperature of buildings and eventually entire cities, but died before his dream came true.
Willis Haviland Carrier, in 1902, was the inventor of the first modern electrical air conditioning. He got the term air conditioning from a man named Stuart W. Cramer. Cramer controlled the humidity of his textile mill by combining moisture with ventilation. Evaporation of water in air to provide a cooling effect is now known as evaporative cooling. After the demand for modern electrical air conditioners went up, Carrier formed the Carrier Air Conditioning Company of America which is currently the largest manufacturer and distributor in the world of heating, ventilating and air conditioning (HVAC) systems.
New developments in air conditioning continue to this very day. Now there is a priority on increasing energy efficiency and improving indoor air quality. So, when you are kicking back on your couch, covered with a light blanket as the sun blazes outside, you now know who to thank for your satisfaction with the surrounding environment. That may be the very definition of cool.