56 ECONOMIC GEOLOGY. 



be glad to hear from you further in this matter, and shall spend here the rest of the 



month. 



Very truly yours, T. STERRY HUNT. 



Phenixville, Pa., June 12, 1875. 



Iron. 



There are several localities where an abundant supply of this ore 

 exists. At Franconia the ore was smelted for sixty years ; and the iron 

 manufactured is more highly prized tliian that made in other states. The 

 remoteness of our state from the coal fields, and the decimation of our 

 forests whereby the yield of charcoal has fallen off, have led to the aban- 

 donment of iron mining at Franconia. 



The vein is of magnetic iron, associated with hornblende, epidote, gar- 

 net, mispickel, and other minerals. It is stated by Jackson to be from 

 3i to 4 feet wide. It has been opened for several hundred feet on the 

 steep south slope of Ore hill in Lisbon, and hence is unnecessarily ex- 

 posed to accumulate rain-water. A shaft is situated low down, said to 

 be 150 feet deep. At the upper end of the cut there is a curve in the 

 vein, amounting practically to a bonanza, beyond which the direction 

 taken by the vein is uncertain. A short adit on the west side of the hill 

 beyond did not discover the vein, as was expected. The vein dips 70° S. 

 40° E. The rock on the west side of the vein is hornblende schist and 

 gneiss. 



Furnaces were erected for the manufacture of iron here in 181 1, and 

 continued in blast till 1870. Charcoal was the fuel employed. Dr. Jack- 

 son has given a full account of the special process of the manufacture of 

 the iron, to which those interested are referred. It seems that the an- 

 nual yield varied from 250 to 500 tons of pig iron, of which a part was 

 reduced to wrought iron in a forge. The following figures expressed the 

 cost of manufacture : 



The proportions used in charging the blast furnace were 15 bushels of charcoal, 5 

 boxes each containing 56 pounds of magnetic ore, one box of limestone for flux. The 

 average daily product was 2^ tons of pig. From 200,000 to 300,000 bushels of charcoal 

 were annually consumed, taking 160 bushels for each ton of iron made. Hard wood 

 charcoal cost $4 per hundred bushels, spruce or soft-wood charcoal, $2.50 per hundred. 

 The limestone cost $1 per ton. The ore cost $6 per ton at the furnace at Franconia 

 village, two or three miles distant from the mine. The items were these : mining, $s i 



