24 SULPHUR. — CHLORINE. 
is mostly procured as an article of commerce. But 
it is also disseminated among many other rocks. 
Combined with iron, it forms a beautiful mineral, 
called iron pyrites, of a yellow colour, often mis- 
taken by the ignorant for gold. Most of the lead 
ore is also combined with sulphur, forming a sul- 
phuret. The same is also true of zinc and copper. 
Gypsum, or plaster of Paris, is lime combined with 
sulphuric acid, and is therefore called sulphate of lime. 
In Sicily and some other parts of the world, sul- 
phur is found in masses or layers, between clay and 
marl formations. In such cases it is usually accom- 
panied by gypsum, rock-salt, or peat. Sicily is well 
known to be the sulphur-market of the world. It 
is obtained by putting the clayey marl containing it 
in stoves or ovens, with an inclined bottom which 
terminates in a canal ; the sulphur, as it melts, thus 
flows into vessels prepared to receive it. 
Many springs contain sulphur, dissolved and com- 
bined with hydrogen gas, which, on escaping, a 
precipitate of sulphur ensues. Such springs exist at 
Avon in this state, and at Fauquier, and many places 
in Green Brier county and other parts of Virginia, 
near St. Louis, in Missouri, &c. We generally find 
sediments and deposites of sulphur in the vicinity or 
on the borders of such springs. Such waters are 
very efficacious in the cure of cutaneous and other 
chronic affections. 
Sulphur is disseminated throughout the ocean, as 
It forms a constant ingredient in sulphate of soda, 
which is a constant ingredient of salt water. 
Chlorine derives its chief importance from the 
fact that, in combination with hydrogen, it forms 
muriatic acid, which, united with soda, forms the 
muriate of soda, or common sea or table salt. This 
forms about 2.5 per cent, of sea-water. Of course 
rock salt contains an immense quantity of chlorine 
spectacle is presented ; the floor, which burns with a blue flame, 
consists of sulphur mixed with earthy matter." 
