A System of Instruction in the Practical Use of the Blowpipe Part 55

(5) in borax. --

(6) in mic. salt. --

(7) with carb. soda. As the preceding.

(8) Special reactions. --

Mineral. White a.r.s.enic

Formula. AsO^{3}.

Behavior

(1) in gla.s.s-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 gla.s.s-tube sealed at one end, is reduced and metallic a.r.s.enic sublimes.

MERCURY.

Mineral. Native mercury

Formula. Hg.

Behavior

(1) in gla.s.s-bulb. Volatilizes with little or no residue and recondenses in neck of bulb.

(2) in open tube. --

(3) on charcoal. Is volatilized.

(4) in forceps. --

(5) in borax. --

(6) in mic. salt. --

(7) with carb. soda. --

(8) Special reactions. --

Mineral. Cinnabar

Formula. HgS.

Behavior

(1) in gla.s.s-bulb. Volatilizes sometimes leaving a slight earthy residue, and re-condenses as a black sulphide.

(2) in open tube. If gently heated is decomposed into metallic mercury, which volatilizes and recondenses in the upper part of the tube, and SO^{2}, which pa.s.ses off as is easily recognized by its odor and bleaching properties.

(3) on charcoal. Is volatilized, generally leaving a small earthy residue.

(4) in forceps. --

(5) in borax. --

(6) in mic. salt. --

(7) with carb. soda. With carbonate of soda and cyanide of pota.s.sium is decomposed and metallic mercury volatilized.

(8) Special reactions. When in the preceding experiment the mercury has been entirely dissipated, the alkaline residue laid on silver gives a sulphur reaction.

Mineral. Native amalgam

Formula. AgHg^{2}.

Behavior

(1) in gla.s.s-bulb. As native mercury, but leaves a residue of pure silver.

(2) in open tube. --

(3) on charcoal. The mercury volatilizes leaving the silver, which fuses to a bead, and, in the oxidizing flame, incrusts the charcoal with its characteristic oxide.

(4) in forceps. --