(2) in open tube. If gently heated in a good current of air passes off as AsO^{3}, which is partly condensed as a white sublimate in the upper part of the tube. (3) on charcoal. Passes off as AsO^{3}, which thinly incrusts the charcoal beyond the assay. (4) in forceps. Colors the flame blue. (5) in borax. -- (6) in mic. salt. -- (7) with carb. soda. -- (8) Special reactions. -- * * * * * Mineral. Realgar Formula. AsS^{2}. Behavior (1) in glass-bulb. Fuses, enters into ebullition and is sublimed as a transparent red sublimate. (2) in open tube. Gently heated passes off as SO^{2} and AsO^{3}, the latter of which is redeposited in the upper part of the tube. (3) on charcoal. Fuses and passes off as arsenious and sulphurous acids. (4) in forceps. Fuses and colors the flame blue. (5) in borax. -- (6) in mic. salt. -- (7) with carb. soda. As on charcoal, except that the S combines with the alkali forming NaS, which on silver gives the sulphur reaction. (8) Special reactions. -- * * * * * Mineral. Orpiment Formula. AsS^{3}. Behavior (1) in glass-bulb. As the preceding, except that the sublimate is of a dark yellow color when cold. (2) in open tube. As the preceding. (3) on charcoal. As the preceding. (4) in forceps. As the preceding. (5) in borax. -- (6) in mic. salt. -- (7) with carb. soda. As the preceding. (8) Special reactions. -- * * * * * Mineral. White arsenic Formula. AsO^{3}. Behavior (1) in glass-bulb. Sublimes without fusion and re-condenses in white crystals. (2) in open tube. -- (3) on charcoal. Sublimes and is partly recondensed on charcoal forming a white incrustation. (4) in forceps. Colors the flame blue. (5) in borax. -- (6) in mic. salt. -- (7) with carb. soda. -- (8) Special reactions. Heated with charcoal in a glass-tube sealed at one end, is reduced and metallic arsenic sublimes. * * * * * MERCURY. * * * * * Mineral. Native mercury Formula. Hg. Behavior (1) in glass-bulb. Volatilizes with little or no residue and recondenses in neck of bulb. (2) in open tube. --