No. 112.] 821 



over, and contain from 75 to 85 cords of 4 feet wood. Seven to 

 nine days are required for burnii^, and from six to eight daji 

 more, after closing the vents, for tlie fire to go out, and cool ready 

 for opening. The average yield of coal, is 1000 bushels for 

 every 20 cords of wood." 



The process of separating the crude ore to prepare it for use 

 or exportation, is an interesting operation, and not generally un- 

 derstood. I have been obligingly furnished with the outline. 

 " A kiln, the walls laid up of stone on three sides, about 30 feet 

 long, 15 feet wide and 10 high, is the most approved size. In 

 this kiln, wood, in logs, is placed on cross pieces, from 6 to 10 

 inches thick ; on top of the wood, the iron ore is placed, as it 

 comes from the mine, the largest pieces next the wood ; the top 

 of the kiln, when loaded, is covere<^l with fine ore, which confines 

 the heat in the kiln. In twelve hours, after firing, the front half 

 of the kiln of ore is roasted, ready for the stampers. The ore is 

 pulverized by heavy stampers, and then passes through grates on 

 to seive plates, under the stamper trough. That which is fine 

 enough passes through; and is carried, by water, into an adjoin- 

 ing room, whence it is taken, by elevators or cups, from trunking 

 boxes, and dropped near tlie vats or tubs, in which the seives are 

 worked. This separates the silex, and other foreign substances, 

 from the iron ore. The seives are worked in water with a verti- 

 cal motion, by a horizontal gig shaft. One seive, may work through 

 about four tons, of clear ore, in twelve hours."* 



The works of Penfield k Co., standing on Putnam's creek, in 

 the central part of Crown Point, comprehend a furge of four (ires, 

 capa])leof pro(hi(in2j, annually, one thousand tons of irun, and a 

 foundery, with j>atterns and fixtures, for the manufacture of Ibrge 

 anvils, hammers, husks, and heavy shafts adapted to modern 

 furnaces. 



I have thus attom[»ted to sketch some of the most prominent 

 iron manufact'trics in the county of Essex. Numerous works of 

 less magnitude, but ♦•ntitlcd to nearly equal consideratioTi, as they 

 affect the great hifln^trinl n-n-rr?*? nf (he country, are disscmina- 



• Letter Col. C. D. Darton. 



