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BUREAU OF AMERICAN ETHNOLOGY 



[Bull. 1S2 



(4) The iron "nuggets" and partially finished tools are microscopically of the 

 type of iron produced by furnaces of earlier types than the cupola, blast furnace, 

 or converter. 



(5) No stock piles of iron ore, fuel (charcoal), or flux (shells or limestone) 

 have been found. 



(6) No remains of furnaces, forges, or air blowing devices have been found. 



Those samples sent to the John Woodman Higgins Armory were 

 later referred to the Byers Plant Laboratory to determine the com- 

 position and probable age. E. B. Story, metallurgist, reported on the 

 analyses while C. J. Summerfield made the actual laboratory tests. 

 Their report states : 



Three very interesting old ferrous metal specimens were submitted by the 

 John Woodman Higgins Armory. 



Our investigations indicate rather conclusively that the material of all three 

 specimens was made by direct fusion. On the premise it can be estimated that 

 these three iron specimens are at least 300 years old because in the early part of 

 the seventeenth century direct reduction methods gave way to the manufacture 

 of iron by fusion methods in reverberatory hearth furnaces. 



The specimens could be much older than 300 years but the age cannot be 

 determined by a study of the chemical and physical properties alone. 



To make these tests, a small portion was cut from each of the samples. These 

 were prepared for macro-examination. The general overall etch pattern in each 

 case revealed a pronounced heterogeneous macrostructure. No evidence of 

 what is known as a piling structure was observed in any of the specimens and it 

 could be concluded even at this preliminary stage of examination that the 

 wrought iron was very likely produced by some early "direct reduction" process. 



These same specimens were then prepared for microscopic examination. In 

 all three samples ferrite areas and pearlite areas of low and high carbon concen- 

 tration were found. Some of the ferritic areas appeared to be relatively low in 

 phosphorous concentration, while other ferritic areas were phosphorous rich. 

 Inasmuch as the microstructure was so heterogeneous in all three specimens, it 

 was decided to select such typical areas as v/ould be representative for these 

 microstructures as reproductions for this report. . . . Taken as a whole, they 

 reflect the "direct reduction" method of wrought iron production. ... It is to 

 be noted that some of these structures or a combination of most of them were 

 found in each of the specimens examined. 



The remaining portion of each sample received was hammered into thin sec- 

 tions and cut into small clippings for a chemical analysis. A complete analysis 

 could not be made due to the insufficient amount of material available ; analyses 

 follows : 



Table 22. — Chemical analyses of iron objects from the Huntley and Russell tracts 



Element 



Manganese. 

 Phosphoras 



Sulphur 



Silicon 



Sample 1 Sample 2 Sample 3 



Percent 



0.010 



.262 



.009 



.019 



Percent 

 0.004 



.019 

 .140 



Percent 



0.006 



.138 



.011 



.035 



Such variation in chemistry is not unusual for wrought iron produced by 

 "direct reduction" methods. Almost any combination of P, Mn, S, and Si has 

 been found in "direct reduction" wrought irons. 



