A vacuum flask (also known as a Dewar flask, Dewar bottle or Thermos) is an insulating storage vessel which keeps its contents hotter or cooler than its surroundings. Invented by Sir James Dewar in 1892, the vacuum flask consists of two flasks, placed one within the other and joined at the neck. The gap between the two flasks is partially evacuated of air, creating a near-vacuum which prevents heat transfer by conduction or convection.
Vacuum flasks are used domestically to keep beverages hot or cold for extended periods of time, and for many purposes in industry.
Read more about Vacuum Flask: History, Design, Domestic Use, Research and Industry, Safety, Security
Famous quotes containing the words vacuum and/or flask:
“If it were possible to have a life absolutely free from every feeling of sin, what a terrifying vacuum it would be!”
—Cesare Pavese (1908–1950)
“Now who could take you off to tiny life
In one room or in two rooms or in three
And cork you smartly, like the flask of wine
You are? Not any woman. Not a wife.”
—Gwendolyn Brooks (b. 1917)