FHYSICAL PROPERTIES OF SUtTHUR.

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Waters, and in caverns adjacent to volcanos; sometimes also incoal-mines. It is found in combination with most of the metals.When united to iron it forms the mineral, called martial pyrites,or sulphur pyrites. All the ores known by the name of pyritesof which there are a vast variety, are combinations of sulphurwith different metals ; and hence the names of copper, tin,arsenical, See. pyrites. It exists likewise in combination withalumine and lime; it then constitutes different kinds of schistus,or alum ores.

PHYSICAL PROPERTIES OF SULPHUR.

Sulphur is a combustible, dry, and exceedingly brittle body,of a pale lemon-yellow colour. Its specific gravity is 1 . 990 .It is destitute of odour, except when rubbed or heated. It isof a peculiar faint taste. It frequently crystallizes in entireor truncated octahedra, or in needles. If a piece of sulphur ofa considerable size, be very gently heated; as for example, byholding it in the hand and squeezing it firmly; it breaks to pieceswith a crackling noise. It is a non-conductor of electricity, andhence it becomes electric by friction. When heated, it first sof-tens before it melts, and its fusion commences at 184° Fahr.; at28f»° it becomes volatilized, and takes fire at 302°. In the be-ginning of fusion it is very fluid, but bv continuing the heat itgrows tough, and its colour changes to a reddish brown. If inthis condition it be poured into water, it remains as soft as wax,and yields to any impression. In time however it hardens againand recovers its former consistence.

It unites with most of the earths and with all alcalies, and be-comes soluble, when thus combined, in water. It unites to mostof the metals and renders them brittle and fusible. It is solublein oils; water takes up a minute quantity, as does ardent spiritby means of heat. It dissolves in hidrogen gas. It does notcombine with charcoal, but unites to phosphorus by fusion.