On September 20th 1842 James Dewar, inventor of the vacuum flask, born in Kincardine-on-Forth.
He was educated at Kincardine Parish School and then Dollar Academy. His parents died when he was 15. He attended the University of Edinburgh where he studied chemistry under Lyon Playfair (later Baron Playfair), becoming Playfair's personal assistant. Dewar also studied under August Kekulé at Ghent. Dewar was interested in cryogenics, the science of extreme cold and in 1898 he was the first person to make liquid hydrogen, which at the time was the coldest substance ever produced.
Cooling gas to the point where it liquefies was an expensive process and Dewar needed to find a way to prevent very cold liquids evaporating while he worked with them. He built boxes insulated with cork, hay or crumpled newspapers, but none kept the liquids cold enough. Eventually he designed a double-walled glass flask and removed the air from the space between the two walls, creating a vacuum. Liquid put inside the flask stays at the same temperature because there are no air molecules through which heat can transfer.
In the pic is one of the earliest trial flasks, later vessels had a silver coating to stop the heat being directly transmitted. Nowadays rockets are fuelled by supercooled gases stored in modern Dewar vessels that can keep liquids cold for nearly three years.
Along with Sir Frederick Augustus Abel, James Dewar also developed the explosive cordite. His early work concerned organic chemistry (suggesting a possible structure for benzene, still called ‘Dewar benzene’), atomic spectroscopy and other topics. Nine times he was nominated for a Nobel prize by distinguished international figures but, significantly, by no Britons.
Dewar never made a penny out the vacuum flask , he lost a court case against Thermos concerning the patent for his invention. While Dewar was recognised as the inventor because he did not patent his invention, he had no way to stop Thermos from using the design, if he had patented it we would possibly be using the name Dewar instead of the common name Thermos for oor wee vessels for taking with us on cold winter days to warm us up.













