Ice can survive as ice for a surprising length of time; suitably protected, it will last the summer through.
This explains why you may sometimes see in the garden of a stately home what appears to be the opening of a tunnel or mine, but which in fact is the entrance to an ice store, a deep, cool recess in which in days gone by the winter ice would be piled up and chipped away at, as required, in summertime.
The first known ice stores were built 4,000 years ago in Mesopotamia. The ancient Greeks used thick-walled buildings filled with winter snow to chill their summer wine.
After the Renaissance, ice houses became fashionable among the gentry on the Continent; the underground chambers were filled during the winter months with ice harvested from lakes and rivers on the great estates; thus the highly valued commodity was then available throughout the year.
Life is more simple nowadays: if you want ice, you simply fetch it from the fridge - but therein lies a paradox. How does the electricity which powers the fridge, a commodity normally associated with generating heat, keep the interior of a fridge so cool? The key lies in the process of evaporation.
You have only to recall how cold you feel after emerging from the water after swimming to realise that the process of evaporation absorbs heat: in this case the heat required to evaporate the drops of water on the body is extracted from the skin.
In the domestic refrigerator, a "working fluid" called the refrigerant is usually a gas which can be easily transformed under pressure into a liquid. The electricity supplied to the appliance operates a pump which compresses the gas into its liquid form: the compression will result in a slight rise in temperature, but this "waste" heat is allowed to drain off into the surrounding air.
The compressed liquid is then led through a pipe to the vicinity of the freezing compartment of the refrigerator, where it is allowed to escape through a tiny valve into a chamber where the pressure is at normal atmospheric value. At this point the sharp drop in pressure experienced by the escaping liquid causes it to "boil" and vaporise.
Since the process of vaporisation, as we have seen, extracts heat from the surroundings, in this case the freezing compartment of the fridge, this compartment experiences a drop in temperature. The gaseous refrigerant is circulated to be compressed again and the process repeated, until the internal temperature of the refrigerator has dropped to the required value.