Thanks alchemists
In the early XX century, the morning of every housewife (or cook) began with a campaign to market for fresh products. They had to be prepared and eaten immediately on the same day, well, in the worst case - tomorrow. True, there were glaciers and cellars.
When exactly people guessed that the cold helps to keep the food fresh, no one knows. Obviously, at first, cool caves were used instead of cellars, and in the cold latitudes - natural ice reserves. In ancient China, Greece and Rome, people have guessed to dig holes and stuff them with ice from the mountains. Of course, such glaciers were only in well-off families. In India, instead of ice, the evaporation method was used: the vessels were wrapped in a damp cloth, the moisture evaporated and cooled the contents. By the way, on the principle of evaporation (only, not water, but another liquid, for example, ether or freon), the device of a modern refrigerator is based.
In the Middle Ages, the use of ice was forgotten, but alchemy began to develop, a by-product of which was a set of useful discoveries. In particular, it was noted that nitrate (potassium nitrate, "Chinese salt", imported by Arabs to Europe around 1200 and quickly became a favorite substance of alchemists) dissolves in water and absorbs heat, that is, the water instantly cools. This phenomenon is used so far - in tourist first-aid kits there is often a sealed package filled with water, in which an ampoule with ammonium nitrate floats. It's enough to hit the knee with the packet and break the ampoule, so that the package will cool by 15 degrees. It can be applied to bruises or wounds instead of ice.
In the thirteenth century, with the help of saltpetre, drinks were cooled and fruit ice was made (which, like everything new, was only a memory of a well-forgotten old one - in the Ancient Rome, patricians enjoyed frozen fruit juice). In 1748, William Cullen, professor of medicine at the University of Glasgow, invented a technology for artificial cyclic cooling using ether: in one chamber a vacuum was created where the ether was boiling and evaporating, cooled the chamber, then the vapor entered another chamber where they condensed and gave off heat to space, and from there again came to the first chamber. It turned out to be a closed cycle - on this same principle is based now the work of any refrigerator.
But to whom is the ice?
The first household refrigerator, or refrigerator, appeared in the United States at the beginning of the 19th century and was very unpretentious. Thomas Moore, an engineer and part-time butter seller, came up with a way to transport oil from Maryland to Washington - in boxes with three-layer walls: steel sheets, rabbit skins and wood. Inside there are two compartments: for oil and for ice. Moore patented the invention, came up with a name for it, and by the middle of the 19th century, slightly refined "refrigerators" (instead of rabbit skins - sawdust, paper, cork) appeared in American and European farms. Soon, in the United States, there was almost no major reservoir left that would not have been harvested in the winter. In the summer, ice sellers kept it in special basements, and ice-sellers were selling icemen. The production of ice grew rapidly, with a large part of it controlled by Russian immigrants from Alaska. For three years in this market the Russian-American company has earned more than gold, for the production of which it was founded.
In 1844, an American physician John Gori created an installation based on the discovery of Cullen and worked on the air. She produced artificial ice for a hospital in Florida, and in addition, she served cold air in the chambers - in fact, it was the first air conditioner. Around the same time, a typhus epidemic swept across the US and Europe, provoked by the use of ice from contaminated water. By that time, the industry had thoroughly muddied the rivers, so that the question of the purity of ice became topical. Both in the New and in the Old World, one inventor after another created more or less successful models of compression machines that produced artificial ice. As refrigerants, they used ether, ammonia or sulfurous anhydride. You can imagine what a stench spread around such refrigerators. Nevertheless, cumbersome noisy machines are well established in the brewing industry and in factories for the production of ice. And what to choose refrigerators for the house - the decision of each person separately.
Freon and Greenpeace
In 1910, General Electric released the first domestic refrigeration unit - a mechanical attachment to the ice boxes, which produced ice. It cost $ 1,000, twice as expensive as a Ford car. The motor in the console was so large that it was usually located in the basement and connected to the "ice box" drive system. Only in 1927 the designers of General Electric, led by the Danish engineer Christian Steenstrup, created a real refrigerator, all parts of which fit into a small cabinet, and even supplied it with a thermoregulator, which has been applied with minor modifications until now. Soon the American chemist Thomas Mead-gley suggested replacing ammonia with newly synthesized gas with Freon, which absorbed more heat during evaporation and was completely harmless to humans. At the presentation of Freon, Mead-glay demonstrated this in a very impressive way: he inhaled Freon's vapors and exhaled a burning candle. No one knew that freon destroys the ozone layer of the earth until the early 1970s, when Greenpeace conducted mass demonstrations and, in the end, forced producers to abandon freon in favor of safe gases.
In 1933 in the United States, almost 6 million housewives proudly took food from the home "refrigerator" of General Motors. In England there were only 100 thousand refrigerators, in Germany - 30 thousand, in the USSR one could read about such curiosities only in the book ("He showed an electric refrigerator cabinet that not only did not require ice, but, on the contrary, prepared it in the form of neat transparent cubes in a special white bath, similar to the photographic: in the closet there were compartments for meat, milk, fish, eggs and fruits. "Ilf and Petrov," One-storied America ", 1937).
Of course, in the Soviet Union, too, worked to create an apparatus designed to facilitate the life of workers. Since 1933, the Moshim-trust plant produced refrigerators that needed to be filled with dry ice. They cost dearly, they often broke down, so the People's Commissar of Food Industry Anastas Mikoyan regularly arranged the designers for the dispensations. The only place where the refrigeration units operated uninterruptedly in the capital was the famous "Cocktail Hall" on Gorky Street, there ice cream was made on American equipment.
By 1939, it was possible either to buy, or steal in the West the drawings of a new device (not working on freon, but on sulfurous anhydride) and start the production of household refrigerators KhTZ-120 at the Kharkov Tractor Plant. But the war began, and it was not at all like that. The cult Soviet freon refrigerator "ZIL" was put into serial production in March 1951. In the same year began to produce "Saratov". But refrigerators became really available only in the 60s. They were reliable, but inferior to the Western in functionality and convenience. In particular, the freezer was located directly in the belly of the refrigerator. Remember: the aluminum door, the eternal drifts of frost inside? Everyone remembers this, who at least once asked himself the question of choosing a refrigerator for the house. In the United States, as early as 1939, the same General Electric produced a two-door refrigerator, and in the early 1950s No frost technology was developed, which allows for dispensing without regular defrosting.
Smart Touch
Since then, the perfection of the refrigerator goes along the path of beauty, convenience and maximum functionality. For example, Samsung Electronics recently introduced a new series of Smart Touch - with external lighting (this is especially convenient if you tear yourself away from your computer at night to refill your nerve-racking body with a creative process.) LED backlighting - both external and internal - all that is needed, not including the light in the kitchen). The designers seem to have thought through all the conceivable comforts: the built-in handle of the refrigerating chamber is designed on the principle of automotive - it is easy to open, even holding heavy packages with products. Folding shelf, fixed in three different positions, allows you to place in the chamber a large cake or other large-sized food. At the lower level of the door there is a special shelf for children's products - kids will enjoy themselves, getting their cottage cheese and juice in the morning.
It seems that the main goal of current manufacturers of refrigerators is to provide consumers with pleasure, including aesthetic. Smart Touch is beautiful like a god: soft blue illumination emphasizes the luxury of a black glass surface (more practical, but no less elegant version - "stainless steel"). If for the husband this is not enough argument to make a choice, it should be convinced such, for example, the detail: the rear wall of the refrigerator is completely flat - this facilitates its installation, and in addition, the dust does not accumulate, and means (that the husband, of course, knows) Do not overheat the motor.
Two models - RL55VTEMR and RL55VTEBG - are equipped with a touch screen, which allows you to control all the functions of the unit with one click. Even on this screen you can write notes to your husband: "Dear, do not forget, we have guests today. If you do forget, and their appearance will be unexpected for you, you can use the department of Cool Select Zone - champagne will cool there six times faster than in our old refrigerator! "
While producers care about us, we, users, also do something to improve our refrigerators. For example, 22-year-old John Cornwell, attached to the refrigerator a catapult that throws the owner of a can of beer so that he can not get up from the couch. The hardest thing is to learn in time, to catch the banks, but the inventor assures us that this is a matter of skill.