PLANT AND SMELTING OPERATIONS. 



G59 



General discussion. — By coiii paring, ill a tabulated form, tbe average data obtained 

 iij tbe preceding- discussions relative to each smelter with the relation between the 

 actual and tbe nominal capacity, it will be possible to some extent to realize the rela- 

 tion between the composition of smelting charge and the time. 



Proportion of flux to ore , 



Proportion of fuel to ore 



Pi oportion of fuel to charge 



Tons of ore per 24 houra (actual capacity) 



Nominal capacity 



Relation of actual to nominal capacity 



25.0 

 45.3 

 36.2 

 28.0 

 35.0 



Note.— The relations of actual and nominal capacity, as here given by Mr. Guyard, cannot be relied npon, as 

 be has ansumed that each smelter was running 365 days during the year, whereas in point of fact the running 

 time must have been much less and must have varied widely in the cases of different smelters, none of which were 

 probably running at their full capacity for any great length of time. (S. F. E.) 



SECTION III. 



PLANT AND SMELTING OPERATIONS 



SMELTING PLANT IN GENERAL. 



Furnaces — All the fumaces of Leadville are built on the same general principles 

 and contain tbe same essential part.s, but they belong to two distinct styles: the rect- 

 angular or square and tbe circular or round. Tbe following description is made from 

 furnaces of both styles used at Smelter B, but a glance at all tbe other furnaces 

 sketched for this report, in which tbe same parts are designated by the same letters, 

 will show that tbe differences are only in details. 



Square furnaces (see Plate XXVI). — Tbe general appearance of these furnaces 

 is that represented in elevation, Fig. 1. The furnace is formed of two independent 

 parts: (1) Tbe masonry C\ sup])orted on a main cast-iron plate support, 0, resting on 

 cast-iron pillars, P. {'2) The crucible A upon which rest the water jackets B. The 

 space between tbe water-jackets and tbe masonry is filled up with fire-brick, b. This- 

 arrangement, as it is easy to perceive, is most convenient for repairs of parts exposed 

 to injury or destruction, and cannot be too highly commended. It is universally 

 adopted in the camp. Tbe masonry is firmly bound by braces <^, tbe system adopted 

 for bracing varying with almost every furnace. Immediately above the feeding-floor, 

 P', are to be seen the feed-holes, H, provided with sliding doors, S'. Tbe smelting charges 

 are thrown into the furnace throagii these boles. 



Tbe different parts of tbe masonry are the following (see vertical section, Fig. 

 3); C is tbe shaft of tbe furnace. The portion of the shaft immediately below tbe 

 feed-holes is called the throat. It is seen also in horizontal section in Fig. 4. D is the 

 chimney. E is the stack. Tbe stack can be closed or opened by means of tbe damper G. 

 The stack is also connected with the dust-condensing chambers by means of tlie sheet- 



