Vapor-compression theory. A long time ago, people were using metal box filled with ice to store their food and drinks. Some of them had to travel 200 miles back and forth to get ice. William Cullen and Ben Franklin were first, who experimented with artificial cooling system, but it did not work at that time. Oliver Evans was the first inventor, who made the steam engine and described vapor-compression refrigeration theory.
Oliver Evens was American inventor, who created many inventions. He made a machine called the steam engine, build his own mill with his brother as a “lab”, he adapted ancient technology in modern world. Oliver was just 22, when he made a successful engine and sold it for over 2,000 dollars! After his success, he hired people to help make engines. At age 26, he’s got some investments to extend his factories. Now he has his 260 factories in a city building engines.
Canning process. It started back at French Revolution, when soldiers did not have food. Napolean had to split his army on small groups, so they can go find food. He also established the program to fund inventors. Nicolas Appert was the first one, who experimented with preserving different foods. At that time, he did not know how the process worked. It took him 15 years to discover how the method works. He got awarded by the government. The main reason of this invention is to feed the army.
These 2 inventions are very important in our modern life. Refrigerators help us to store and keep food fresh for short period of time. Canning is helpful to store food in long term.
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