A gradual refrigeration proceeded through the Pliocene period.
To produce refrigeration the operation is reversed.
It extended the meaning of the term " railroad " to include switches, spurs and terminal facilities, and the term " transportation " to include private cars, and all collateral services, such as refrigeration, elevation and storage.
The city has a monument (1900) to John Gorrie (1803-1855), a physician who discovered the cold-air process of refrigeration in 1849 (and patented an ice-machine in 1850), as the result of experiments to lower the temperatures of fever patients.
In the first refrigeration is produced by the expansion of atmospheric air, and in the second by the evaporation of a more or less volatile liquid.