What was the best-known invention of the man that the cryogenic storage dewar was named after?
Cryogenic storage dewar: A cryogenic storage dewar (named after James Dewar) is a specialised type of vacuum flask used for storing cryogens (such as liquid nitrogen or liquid helium), whose boiling points are much lower than room temperature. James Dewar:  He is probably best known today for his invention of the vacuum flask, which he used in conjunction with extensive research into the liquefaction of gases.
the vacuum flask