The thermos can not only save hot water, but also preserve ice water. This function is determined by the structure inside the bottle. This configuration of the thermos bottle can well prevent the temperature inside the bottle from communicating with the temperature outside the bottle, thereby achieving the purpose of heat preservation.
The small thermos has a long history of invention!
As early as the Northern Song Dynasty, China had the prototype of a thermos bottle. In Europe, the ancient Romans have long known that double-layer containers can keep warm. In the ruins of Pompeii, people have dug up a double-layer container, which is insulated like a modern thermos.