666 TRANSACTIONS OF THE 



able to a sienitic rock below and having sedimentary and palasozoic forma- 

 tions to the west of it. 



As early as 1640, a party of Nassau miners discovered it, who came from 

 New Amsterdam, N. Y., and explored the range of ores from the line of 

 Pennsylvania to Salisbury, Conn. In 1770 it was examined by Lord 

 Sterling and samples sent to Europe.* In 1817, it was owned by Dr, 

 Dowler, a mineralogist. Dr. Keating and Professor Vanuxen examined 

 it in 1819. Dr. McClure, the father of American geology, in company 

 with Dr. Jackson and others, explored it in 1825. Dr. Jackson revisited 

 it in 1849, accompanied by Francis Alger, of Boston. In 1850, zinc was 

 extracted and in 1852, iron was successfully reduced from the ore. During 

 the prosecution of the geological survey of the state, made by Dr. Rogers, 

 he also reported upon this. In the recent survey by Dr. Kitchell, an 

 elaborate report is given upon the ores and mines of the state and this 

 locality. 



" Franklinite was chemically analyzed first by Berthier, who found 



Silica 0.280 



Oxyd of iron 66.082 



Oxyd of zinc 21.395 



Oxyd of manganese 12.243 



" The analyses of Jackson and Hayes vary a little in the proportion of 

 the above materials, but this variation was probably due to a slight varia- 

 tion in the samples offered for analysis. 



" Pure franklinite is a mineral of as definite a constitution as water. A 

 careful comparison of the analysis and of the mineral with various isomor- 

 phous compounds, gives us the formula, (FeO,ZnO)-[-(Pej03,Mnj03,) as 

 exactly representing the composition of franklinite. 



" In the smelting operation, then, as the condition of the high tempera- 

 ture of the alloy with the excess of oxygen is found, the proportion of man- 

 ganese will be materially diminished. In short, analyses of franklinite 

 pig show an average decrease of about seven-eighths of the manganese. 

 The amount of loss it is evident, in practical operations would vary within 

 pretty wide limits. 



" The franklinite pig metal, as ordinarily produced, should be regarded 

 as an alloy of iron with manganese. It deserves this distinction as well 

 from its peculiar properties as its chemical composition. It is more fusible, 

 less oxjdable, harder and of a lighter color than either iron or manganese. 

 For many of the purposes for which ordinary cast iron is used, this com- 

 pound is imnracticablfe ; while, for certain specific uses, the franklinite pig 

 is better fitted than any other known material. We have in this alloy a 

 new raw material for the industrial arts. Its sources are exclusively 

 American ; science and American industry should work out the problem of 

 its application." 



The bad qualities of some kinds of iron ore now in use are occasioned by 



* Dr. Archibald Bruce examined the red oxide of zinc about 1810, and visited the mines m 

 company with Col. George Gibba. ^ _ 



