Boiling-point
See EBULLITION.
Borax is procured by heating boracic acid with carbonate of soda, the carbonic acid being expelled and the boracic acid taking its place. This salt has an alkaline taste and reaction, and possesses the property of dissolving many metallic oxides; hence its use as a flux in the welding of metals. It dissolves off the coating of oxide formed when they are heated, thus presenting a clean surface. See FLUX; SOLDERS.