80 



A YEAR IN SCIENCE 



next, three; the third, six; and the outer tube, ten. 

 "Water heated under pressure much above the boiling 

 point is forced through the three inch tube into the 



Permission United States Geological Survey. 



Fig. 33. Sulphur which has been brought to the surface and 

 consolidated, ready for shipment, at Sulphur, Louisiana. 



beds to melt the sulphur. Air under pressure is forced 

 through the one inch tube. The melted sulphur mixed 

 with air then bubbles up through the outer tubes. The 

 sulphur is collected in large bins built of wood, where 

 it solidifies to form large blocks of practically pure 

 sulphur. These blocks, often containing as much as 

 100,000 tons, are broken up by blasting and prepared 

 for market. 



Physical properties. Sulphur is pale yellow in color, 

 and without taste or odor. It is insoluble in water. 



