PLANT OF SxMELTEU B. 673 



Furnaces — The smeltiug plaut consists of three huge square furuaces, made ot 

 brick. With the exception of the water-jackets they are exactly simiUir in shape,(limeu 

 sious, and capacity. They are represented in elevation and in section ou Plate XXVI. 

 There are besides six circular furnaces, manufactured by Messrs. Fraser & Chalmers, 

 of Chicago. These furnaces are represented in elevation and section on Plate XXVII. 



A full description of both the square and the round furuaces at this smelter 

 has already been given at the commencement of this section, to which the reader is 

 referred for further details concerning their construction. The capacity of the square 

 furnaces is 35 to 40 tons of ore i)er 24 hours, and that of the circular cues 20 to 22 

 of ore in the same time. The heat radiated in trout of these nine furnaces, closely 

 packed in a narrow space, is so great that the men are obliged to constantly water 

 the ground in front of them. The crucibles of hoth square and round furnaces are made 

 of steep, the mixture preferred at these works being two parts of fireclay and one part 

 of coke-dust. The length of runs is various and averages three months. 



Condensing chambers — The Condensation of lead fumes at tuis smelter is of the 

 poorest description. Four furnaces are totally without any condensing apparatus; 

 three furnaces are connected with an oblong sheet-iron box, 50 feet long, 6 feet high, 

 and C feet wide, placed on the feeding-tloor ; and one furnace communicates with a 

 small chamber, 9-foot cube, placed on the same floor. Each chamber is provided 

 with a stack made of sheet-iron. With such inadequate arrangements the works are 

 per|)etually enveloped in a thick atmosphere of smoke and lead fumes, and '' leading" 

 is of frequent occurrence. 



Bartiett filter — During the collection of notes for this report, a most interesting 

 and valuable experiment was being made at these works with a view to the total con- 

 densation of lead fumes. This ex[)eriment was carried on at great expen.se with the 

 elaborate apparatus known as the Bartiett smoke-catcher or filter. It was so successful 

 and the results derived from it are so interesting that the whole deserves a full descrip- 

 tion. The arrangement adopted is shown in Fig. 1, Plate XXVIII. The stack jE of 

 one of the S(piaie furnaces A was coimected by means of the sheet iron flue F' with a 

 Sturtevant fan, £.', drawing the fumes from the furnace and blowing them through the 

 sheet-iron pipe P, about one hundred and tilty feet long, where they parted with their 

 dust, as in an ordinary flue. The pi])e P is connected by means of two sheet-iron 

 branch pipes, P', with two thin sheet-iron boxes, flo'. Each branch l>ipe P' is provideil 

 with a damper or valve, exactly similar to those used in common stove pii)es for the 

 regulation of draft, so that the fumes can be distributed evenly in the boxes or 

 siiut oft' from one and allowed :o enter only the other. Each box is formed of two 

 parts, the dust-chamber a a' and the fireplace N. The dust-chamber is provided with 

 sliding doors 0, placed at each extiemity, and the fireplace with doors (?, placed in 

 front, and sheet iron pipes L at the back which communicate with a stack, L'. The 

 chambers a a' are provided at the top with 28 apertures, to each of <vhich is fastened 

 a cloth bag, b, 30 feet high, suspended to the beams of the light wooden structui-e in 

 which the apparatus is inclosed. This building j¥is provided with very large open- 

 ings for ventilation. W'hen the ajjparatus is at work the fumes, blown in through 

 pipes P P', distribute themselves in the dust-chambers a a' and ascend the cloth bags, 

 through which they filter. The gases come out perfectly colorless and are entirely 

 deprived of any lead dust or even soot. The wind, entering freely through the apei-- 

 MON XII 43 



