658 



GEOLOGY AND MINING INDUSTRY OF LEADVILLE, 



In the preceding charges the proportions are — 



Flux to ore 52 



Fuel to ore 2G aud 28 



Fuel to charge ]7| and 18J 



Charges made at CaHfornia works in February, iSSo. — Mr. J. E. Hardmail had the Ivind- 



nesa to comuuuiicate the following experimental charges, which he made at the Cali- 

 fornia smelting works while superiutendent, chiefly with a view to avoid the use of old 

 slags. 



In the preceding charges the proportions are — 



The following tal)le will aid in the correct iiitcipretation of these iignres; 



It results from this table that for each ton of fuel burned the quantity of ore 

 smelted is equal to: In No. 1, 3.5 tons; inNo. 3, 3.2; in No. •1,3.4; inNo. 5, 3.2; and in 

 No. 0, 3.5 — showing that there is no advantage in using flux instead of old .slag, and 

 that there is a disadvantage in doing so, since fluxes are costly and are apt to carry 

 away no inconsiderable quantities of lead and silver, while old slag costs nothing and 

 is alreadv saturated with lead and silver. 



