Physics: A blowtorch is applied to a sample of aerogel to demonstrate its insulation properties. Aerogel is a new material, which has very high thermal insulation properties and extremely low mass. It is made by adding alcohol to a conventional silica gel to remove water. The gel is then placed in a pressure chamber, and the alcohol removed under super fluid conditions. This prevents the gel from collapsing. The resulting block of silica fibers contains about 90% air, so is very lightweight. Aerogel is being studied as an insulating material and as a holding medium for nuclear fusion fuel. Photographed at the Lawrence Livermore National Laboratory, USA. [1991]