352 JOSEPH STRUTHERS 



ed when the well is abandoned. The method of extracting 

 the sulphur is as follows: Steam at a temperature of 330° F. 

 is forced down the 10-inch and 6-inch pipes under a corre- 

 sponding pressure. When the steam comes in contact with 

 the sulphur (which at 284° F. becomes Hquid), the latter melts 

 and collects in the well as a thin liquid of a specific gravity 

 of about 2. At first the molten sulphur was pumped out 

 through the 3-inch pipe in a manner similar to that followed 

 in pumping petroleum from a well, the working valve being 

 formerly of aluminum, which is not affected by sulphur. It 

 was found, however, that the aluminum was not strong enough 

 to withstand the shock of the heavy column at the change of 

 stroke, and the method had to be abandoned. Later, the 

 1-inch pipe referred to above was introduced into the 3-inch 

 pipe, and through it compressed air was forced. The bubbles 

 of air mixed with the sulphur reduce the specific gravity of the 

 column of sulphur and cause it to rise with rapidity. The 

 sulphur produced is practically refined sulphur, and finds a 

 ready sale on account of its purity and attractive appear- 

 ance. 



It is not practicable to ascertain precisely what occurs 

 at the bottom of the well, but it may be assumed that as the 

 sulphur melts out of the bed it forms a more or less pear shaped 

 cavity, which becomes larger and larger, until finally the in- 

 creased surface exposed to the water is sufficiently great to re- 

 duce the temperature of the water below the melting point 

 of the sulphur, while the impurities of the bed collect on the 

 bottom and the sides of the chamber and protect the sulphur 

 still unfused from the melting action of the heated water. If 

 the bed of sulphur is very pure, the chamber might bo- 

 come quite large in size, when the unsupported overlying roof 

 would fall and allow the water to escape through the over- 

 lying beds. 



Although the Frasch process is very ingenious and the 

 inventor deserves great credit for working out the numerous 

 details, yet its application to the deposits of sulphur has greatly 

 injured them, since the exploitation of the deposit by shafts 

 and the common method of underground mining has now be- 

 come fraught with danger, owing to the uncertain extent of the 



