64 BULLETIN 42, UNITED STATES NATIONAL MUSEUM. 



The metallurgical treatment is illustrated by the following speci- 

 mens : 



Ore. 



(1) Roasted mineral. (54912.) 



(2) Roasted sulphides. (54923.) 



Fuel. 

 (1) Coke from West Virginia. (54902.) 



Flux. 

 (1) Cinder from au iron puddling furnace. (54908.) 



Intermediate products. 



(1) Pig lead, unrefined, from blast furnace smelting. (54875.) 



(2) Slag, from the blast furnace smelting. (54907.) 



(3) First matte. (54905.) 



(4) First matte, roasted. (54935.) 



(5) Second matte. (54906.) 



(6) Second matte, roasted. (.54916.) 



(7) Partially roasted second matte, coated with sublimed sulphur. (54920.) 



(8) Third matte. (54911.) 



(9) Third matte, roasted. (54915.) 



Products. 



(1) Nickel and cobalt matte. (54918.) 



(2) Refined pig lead. (54876.) 



(3) Skimmings from the refinery. (54909.) 



DESLOGE LEAD WORKS. 



The product of the mine is illustrated by the following specimens of 

 the ore : 



(1) Galena, with a little pyrite and limestone, rich lump ore. (54880.) 



(2) Galena, with very little pyrite and limestone, very rich lump ore. (54881.) 



(3) Galena and pyrite, in limestone, characteristic disseminated ore. (54882.) 



The disseminated ore is treated in the concentrating mill as shown by 

 the following scheme, figure 5. 



The material remaining on the top of the sieves "heads" is here 

 called " scrapings," that passing through is called " hutchwork," while 

 the "tails" are called "chats." 



The ore from the mine is delivered to three 15-inch by 9-inch Blake 

 crushers; from these it goes to three 14-iuch by 30-inch rolls and then 

 to a 9-millimetre screen. What passes over this screen goes to three 

 14-inch by 30-inch rolls to be recrushed. What goes through the 9-mil- 

 limetre screen goes to a 7-millimetre screen. What passes over this 

 screen goes to the coarse jigs. There are three pairs of 2-sieved, end 

 lever jigs, and one 4-sieved Collom jig, yielding scrapings, good min- 

 eral, and hutchwork, which is recrushed. The overflow from the first 



