where did the term swamp cooler come from
Evaporative cooler The evaporative cooler was the subject of numerous US patents in the 20th century; many of these, starting in 1906,[2] suggested or assumed the use of excelsior (wood wool) pads as the elements to bring a large volume of water in contact with moving air to allow evaporation to occur. A typical design, as shown in a 1945 patent, includes a water reservoir (usually with level controlled by a float valve), a pump to circulate water over the excelsior pads and a centrifugal fan to draw air through the pads and into the house.[3] This design and this material remain dominant in evaporative coolers in the American Southwest, where they are also used to increase humidity.[4] In the United States, the use of the term swamp cooler may be due to the odor of algae produced by early units.[5]