1921] EDWARDS, SULPHUR MINING ON THE GULF COAST. 65 



much pressure l)eneath the surface that it is necessary to drill wells, 

 called bleed wells, to relieve this pressure by allowing the excess air and 

 steam to escape. So far over 500 productive wells have been drilled on 

 this mound and the entire area is not yet explored. 



Like all other mineral resources this one is not inexhaustible and 

 the day is not far distant when the mounds now known will have been 

 exhausted. At present we cannot estimate the available reserves still in 

 the ground nor can anyone venture to predict the discovery of further 

 workable deposits. There are many similar domes known and ])erhaps 

 as many more to be discovered and explored. How many of these will 

 yield sulphur is not known l)ut at the best it will be a very small per- 

 centage. For the next few years, however, the gulf coast sulphur 

 mines will remain as one of America's valued resources and as, perhaps, 

 the most peculiar mining procedure that has ever been developed. 



