SULPHUR AND PYRITE 351 



During recent years, however, several thousand tons of 

 sulphur have been produced annually in England from tlie 

 accumulated alkali waste of the Le Blanc soda process. Tliis 

 manufactured product is known as chance-claus, or recovered 

 sulphur. The process of its manufacture reproduces, in many 

 respects, the chemical reactions by which natural sulphur is 

 formed from gypsum. 



The development of the sulphur mining industr}^ in the 

 United States has been of ver>^ slow growth, owing principally 

 to the cheapness with which the refined product can be im- 

 ported from Italy. In recent years nearly the entire supply 

 has been obtained from the enormous deposits in the island 

 of Sicily, which supplies, as well, by far the greater part of 

 the rest of the world's demand. The deposits of sulphur which 

 have been worked in the United States are limited in number. 

 The states from which the domestic supply of native sulphur 

 is derived are, in the order of the quantity of their output, 

 Louisiana, Nevada, and Utah. 



In Louisiana an immense deposit of sulphur of the gyp- 

 sum t^-pe occurs in Calcasieu parish, 230 miles west of New 

 Orleans and 12 miles from Lake Charles. This is unquestion- 

 ably the most accessible of the American deposits, and, in 

 all probability, it is the richest as well. Exceptional diffi- 

 culties have been encountered in developing the mine, owing 

 to quicksand and gravel which overlie the mineral. As proved 

 by a number of drill holes the bed of sulphur is from 110 

 to 125 feet in thickness, the upper level being about 350 feet 

 below the surface. 



In the working of the Frasch process, a well is sunk by a 

 drill precisely in the same way as for petroleum. This well 

 is cased with an iron pipe 10 inches in diameter, which enters 

 the rock overlying the bed of sulphur for a distance of 10 feet, 

 the joint being subsequently sealed as wtU as possible by molt- 

 en sulphur in order to exclude water. Inside the 10-inch pipe 

 is placed one of 6-inch diameter; inside the latter, one of 3-inch 

 diameter; and, finally, inside the 3-inch pipe, one of 1-inch 

 diameter. The well itself is carried down to the bottom of the 

 sulphur bed, and the 6-inch and smaller pipes are extended 

 nearly to the bottom of the well. The inner pipes are recover- 



