Before the invention of the refrigerator,icehouses were used to provide cool storage for most of the year. Placed near freshwater lakes or packed with snow and ice during the winter, they were once very common. Natural means are still used to cool foods today. On mountainsides, runoff from melting snow is a convenient way to cool drinks, and during the winter one can keep milk fresh much longer just by keeping it outdoors. The word "refrigeratory" was used as early at least as the 17th century[2]
The history of artificial refrigeration began when Scottish professor William Cullendesigned a small refrigerating machine in 1755. Cullen used a pump to create a partialvacuum over a container of diethyl ether, which then boiled, absorbing heat from the surrounding air.[3] The experiment even created a small amount of ice, but had no practical application at that time.