Hot Tea, Cold Science: The invention that keeps things just right
Let’s rewind to 20 September 1842 . That’s the day Sir James Dewar was born, a name that might not immediately ring bells unless you’ve spent time in cryogenics or have a fondness for keeping your tea hot during long site visits. But Dewar’s contribution to engineering is quietly profound. He’s the mind behind the vacuum flask, a deceptively simple invention that’s had a surprisingly wide impact. The Challenge of Storing Cold Liquids Dewar wasn’t trying to invent a lunchbox accessory. His work was rooted in experimental physics, particularly in the study of gases at extremely low temperatures. In the late 19th century, he was attempting to liquefy hydrogen, a task that required storing it at temperatures close to absolute zero. The problem? As soon as you collect the liquid, it starts warming…