658 



GEOLOGY AND MIXING INDUSTRY OF LBADVILLE. 



In the preceding charges the proportions are 



Flux to ore 53 



Fuel to ore 26 and 28 



Fuel to charge 17 and 18J 



Charges made at California works in February, iSSo Mr. J. E. Hardman had the kind- 

 ness to communicate the following experimental charges, which he made at the Cali- 

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



slags. 



In the preceding charges the proportions are 



The following table will aid in the correct interpretation of these ligures: 



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 ; in No. 3, 3.2 ; in No. 4, 3.4 ; in No. 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 sla^j costs nothing and 

 is already saturated with lead and silver. 



