WELLS, William Charles. An Essay on Dew, and several appearances connected with it. Philadelphia: Haswell, Barrington, and Haswell. 1838.
First US edition, originally published in Britain in 1814. A classic of meteorology, for which Wells was awarded the Rumford Medal of the Royal Society. "It would take too much space to follow all of Wells' ingenious experiments, but his conclusions can be stated. The cooling of the Earth's surface, and of the bodies that accumulate dew, is the result of radiation to space. This radiation is always going on, but can be largely interrupted by clouds; and in the daytime it is overbalanced by the radiation to the Earth from the Sun" (Middleton). It is clear that Wells had hit upon what is now called the "greenhouse effect." Moreover, it was of "major importance in the development of the science of ventilation, particularly in its relation to relative humidity and the influence of the latter on the comfort of the occupants of factories, ships, theatres, etc". (Garrison-Morton 1604).