Child's Thermos flask, 1950
Flasks like this are based on an invention of the scientist Sir James Dewar in 1892. This was an insulated glass container which Reinhold Burger, one of his students, used to market the 'Thermos' flask (from the Greek word for heat) in 1904. Because it is insulated it can keep your cold drinks chilled as well, but it was the revolutionary new idea of keeping things hot which really appealed to the public back then.
When the original owner gave this flask to the Museum, it brought back her memories of taking it on trips to Southend with her aunt in the late 1940s. They would picnic on the beach 'eating gritty sandwiches and drinking lukewarm tea'. This all sounds most uncomfortable, but at that time it was wonderful to be able to go to the seaside again. It had been more or less impossible during the Second World War (1939-1945). Petrol for journeys was in very short supply, and most of the beaches had been closed off as part of the defences against enemy invasion.