|Thermos, Also called: Dewar flask an insulating flask that has double walls, usually of silvered glass, with an evacuated space between them. It is used for maintaining substances at high or low temperatures|
vessel with double walls, the space between which is evacuated. It was invented by the British chemist and physicist Sir James Dewar in the 1890s. Thermos is a proprietary name applied to a form protected by a metal casing
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