The concept of a thermos bottle is very simple: the bottle has an inner wall and an outer wall; there is a vacuum between the two walls, and there is nothing (not even air inside). Heat cannot be transferred through the vacuum, so any liquid poured into the bottle can maintain its original temperature for a long period of time.
This is why the thermos bottle keeps the drink warm in winter and cold in summer. Many people who have participated in many tours find it difficult to imagine what it would be like without a thermos.
But the thermos bottle was not invented until 1892, although its inventor did not realize how useful it would be. The inventor is Scottish scientist James Dewar.
However, German glassmaker Reinhold Berg, who realized that thermos bottle flasks can be useful in various situations. He obtained the patent for the thermos flask in 1903 and made a plan to put it on the market.
Berg even held a contest to give his thermos a good name. The winning name he picked was "thermos bottle", which is the Greek word for heat.
Berg's products were very successful, and soon he shipped the thermos to all over the world.
Thermos bottle is often used for scientific purposes, for example, when the liquid needs to be kept at a constant temperature. Vaccinia vaccine, serum and other liquids are also often transported in thermos bottle.