of Inn, Carhone and VUrtous Matur, 133- 



The attraftion of iron for carbone, continues Citizen Clouet, is fuch that, at a very high 

 temperature, it will take it even from oxygen. He proves this by the following experiments : 

 Let iron, in fmall pieces, be put into a crucible with a mixture of equal parts of carbonate of 

 lime and clay ; let the heat be urged to the degree neceffary to weld iron, and kept at that 

 elevation for an hour, or more, according to the fize of the crucible : the metal being then 

 poured into an ingot mould, will prove to be fteel of the fame quality as caft-fteei. 



The oxydes of iron arc equally fufceptible of paffing through the ftates of foft iron, fteel, 

 and fufible or caft-iron, according to the proportions of coal made ufe of. The black oxyde of 

 iron, of which the ftate appears to be the moft conftant, becomes iron when heated in the 

 crucible with an equal bulk of charcoal powder : a double quantity affords fteel. A progreffivc 

 augmentation imparts the characters of the white and the grey caft-iron. 



Laftly, Citizen Clouet obferved the fame tranfitions dependant on the refpeftivc quantities, 

 by heating caft-iron, and the oxyde of iron ; caft-iron and forged-iron ; the oxyde of iron and 

 iron ; the oxyde of iron and fteel. No more then one-fifth of caft-iron is necaflary to 

 convert bar-iron into fteel. 



Iron and its oxyde do not intimately unite together. The black oxyde, mixed with half die 

 quantity of charcoal which would be neceflary for its reduiSion, affords iron, which is foft, 

 pofleffing little tenacity, of a black colour, and indiftindl fradturc. 



One-fixth of oxyde reftores common fteel to the ftate of iron, by heating them together ia 

 the forge, or in the way of cementation. 



At the end of his memoir. Citizen Clouet has given obfervations on the manner of producing 

 caft-fteel, and the furnances proper for this effedl. 



He determines the nature of the fluxes, the degree of heat, the quality of the crucibles, the 

 precautions for cafting the ingot, the method of forging this kind of fteel, the proceffes to be 

 followed in experiments at the forg^ upon two kilogrammes of the materials, and the propor- 

 tions to be given to a reverberatory furnace capable of heating four crucibles, each containing 

 12 or 13 kilogrammes of fleel (about 28 pounds avoirdupois each crucible). 



He remarks, that the mere ingredients of faline glafs cannot be dire<31y ufed in this procefs; 

 that glaffes, which are too fufible, render the fteel difficult to forge ; that fteel, kept for a long 

 time in fufion, takes up more glafs than is proper ; and, laftly, that the melted matter muft 

 be ftirred, and the glafs carefully taken off before cafting, in order to prevent its mixing with 

 the fteel. 



The Commiflaries of the Inftitute proceeded to repeat and verify the experiments of Citizen 

 Clouet. Thefe operations, which are related at length, were as follows, i. Six heftogrammes 

 (about 21 oz. avoirdupois) of filings of farrier's nails, and four of a mixture of equal parts of 

 white marble, or carbonate of lime, and baked clay of an Heffian crucible, both reduced to 

 powder, were well blended together, and expofed to the heat of a forge-furnace urged by three 

 bellows-pipes for an hour and a half. The crucible failed at the firft experiment ; but, on 

 repetition, a bar of fteel was afforded. 2. Upon making the experiment with Macquer's 

 furnace, the fufion was not complete, though the fire had been urged to 151" of Wedgwood. 

 3. Ia another excellent wind-furnace, 367 grammes (about 13 oz. avoirdupois) of fmall-drawn 



iron 



