The first known and recorded artificial refrigeration system was demonstrated by a man named William Cullen in 1748 at the University of Glasgow. After that, many scientists and inventors began following in Cullen’s footsteps. In 1805, Oliver Evans designed the first refrigerator to use vapour instead of cold liquid and 1902, Willis Haviland Carrier demonstrated the first air conditioner. In between these two dates, dozens of scientists made improvements and variations that all contributed to bringing use the modern day refrigerators we now have.
Separate machines that froze food became popular during the 1940’s, however back then it was called a "deep freeze”. The next two decades brought with it great technological advancements such as automatic defrosting of food and automatic ice making. Most freezers nowadays operate around -18 degrees Celsius which is approximately 0 degrees Fahrenheit. Modern freezers, commonly purchased at the same time as a refrigerator, can either be bought attached to the fridge (underneath or on top) or it can be a separate unit entirely although there is usually not much difference between the two in terms of appearance. Thanks to advancements in 1922, which saw the first ice cube tray, many modern freezers now come with an ice dispenser that is either built into the freezer door on the inside or outside. It is usually outside to make dispensing ice more convenient.
Not many people know that medieval people who lived in castles also used to use a form of refrigeration. If you visit the ruins of a castle, you will often find somewhere in the grounds an underground space that just looks like a big room. You will probably notice that it is rather cold down there. This is because you are standing in a medieval refrigerator. Because of the cold temperature underneath the ground, people used to keep their food down there for storage.
Separate machines that froze food became popular during the 1940’s, however back then it was called a "deep freeze”. The next two decades brought with it great technological advancements such as automatic defrosting of food and automatic ice making. Most freezers nowadays operate around -18 degrees Celsius which is approximately 0 degrees Fahrenheit. Modern freezers, commonly purchased at the same time as a refrigerator, can either be bought attached to the fridge (underneath or on top) or it can be a separate unit entirely although there is usually not much difference between the two in terms of appearance. Thanks to advancements in 1922, which saw the first ice cube tray, many modern freezers now come with an ice dispenser that is either built into the freezer door on the inside or outside. It is usually outside to make dispensing ice more convenient.
Not many people know that medieval people who lived in castles also used to use a form of refrigeration. If you visit the ruins of a castle, you will often find somewhere in the grounds an underground space that just looks like a big room. You will probably notice that it is rather cold down there. This is because you are standing in a medieval refrigerator. Because of the cold temperature underneath the ground, people used to keep their food down there for storage.
