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is first covered with about six inclies of fine ore distributed as evenly as 

 possible over the clay soil. Sticks of cordwood of nearly uniform size 

 should be placed side by side across both sides and ends of the rect- 

 angular area. The whole interior of this can be filled in with old stumps 

 roots, ties or cordwood, but in such a way as to form a level and solid bed 

 for the ore to rest on. Overall this is placed small wood and chips to fill 

 up all interstices, care being taken to provide small canals filled with 

 kindlings at intervals of 8 or lo feet leading from the outer air to the 

 chimneys along the centre of the heap. These chimneys which assist 

 in rapidly and certainly kindling the whole heap are usually built of 

 four sticks or old boards, so fixed together as to leave an opening and 

 communicating below with the daaught passages. Five or six of these 

 chimneys suffice for each pile, and they should project 2 feet above the 

 upper surface of the heap, so that no pieces of ore could fall into the 

 flue opening. The coarsest class of ore is first thrown on, then the 

 ragging or medium, on top of which is scattered a layer of rotten wood 

 or chips, and lastly the whole heap is covered over with fines till it 

 reaches a height of about 6 feet, The whole structure should then 

 form a shapely rectangular pile with sharp corners and as steeply slop- 

 ing sides as the ore will naturally lie on without rolling (about 45°). 

 Only a portion of the fine ore is put on at first, the rest being shovelled 

 on after the fire is fairly started. The best way to light the pile is to 

 place a quantity of ignited cotton waste saturated with coal oil down 

 each of the chimneys. About 12 hours after firing the whole heap 

 should be pouring forth dense yellow fumes of sulphurous acid. Great 

 attention is at first paid to the pile to prevent undue local heating 

 which frequently causes partial fusion of the ore, and this can at once 

 be prevented by covering the place with more fines. This heap should 

 then burn from 50 to 70 days when the outer covering of raw or partially 

 roasted ore is removed, and the remainder of the heap conveyed a few 

 yards in wheelbarrows to a sunken railroad which runs alongside of the 

 roast-yard. When filled, the cars are pushed up another steep grade 

 along a track running over the bins back of the smelter. The slop- 

 ing sides and corners of a pile are frequently covered with almost 

 raw ore, this evil being often remedied by placing ignited sticks 

 of cordwood around the whole structure, or by building a new pile in 



