Source: http://front.kinja.com/this-flame-is-made-of-pure-water-1453720981/@jesusdiaz
Scientists have invented a new low-cost method to create a safe welding flame using water as its only fuel. Called the Safeflame, the device splits water in oxygen and hydrogen, recombining them both outside of the torch's mouth to create fire. And the only byproduct is water.