138 
FLORIDA STATL GEOLOGICAL SURVEY. 
SULPHUR DEPOSITS FORMED FROM HYDROGEN SULPHIDE. 
As stated in the last paragraph, sulphur waters are not to be 
regarded as resulting from beds of pure sulphur. On the con¬ 
trary, it is probably true that these waters may, in some instances, 
result in the formation of such deposits. Hydrogen sulphide, 
when acted upon in the water by oxygen, breaks up, forming 
water and sulphur; the reaction being H2S+0=H20+S. It is 
thus possible that H 2 S in the underground water, or escaping 
from the underground water, may become disassociated, forming 
deposits of pure sulphur. Such deposits of economic value have 
not been reported in Florida. It is a noteworthy fact, however, 
that one large mass of sulphur has been found underneath phos¬ 
phate beds in Citrus County.* The formation of this mass of 
sulphur is probably due to hydrogen sulphide. A flocculent white 
coating of sulphur, or a sulphur compound invariably forms 
around sulphur springs and flowing sulphur wells. 
ABSENCE OF HYDROGEN SULPHIDE FROM CERTAIN WATERS 
IN FLORIDA. 
The absence of hydrogen sulphide from the first water obtained 
from areas in which the open porous limestone is the surface 
formation, has already been stated. It is a well-known fact that 
if sulphur water is allowed to stand in the open air the gas will 
escape. This method of freeing water from an excess of H 2 S gas 
is a common practice wherever sulphur water is used for domestic 
purposes. Wherever porous limestone lies at or near the surface 
the sulphur gas, which the water may have contained, will find a 
ready means of escape. In other parts of the State, where 
compact and impervious formations rest upon the limestone, the 
gas is prevented from escaping and sulphur water is obtained. 
*Florida Geological Survey, First Annual Report, p. 44, 1908. 
