1874.] y*-' [Lesley. 



Gray Crystalline Stone, sou h side of road from Half Moon Run to 

 Hostler Bank, near the Half Moon Run. 



Silicic Acid 2.71 



Alumina 11 



Carbonate of Iron 1.80 



" "Lime 83.91 



" Magnesia 11.14 



Sulphate of Lime 12 



Organic Matter 31 



Smooth Grey Stone from north side of road near the foregoing : 



Silicic Acid... 6.87 



Alumina 1.35 



Carbonate of Iron 75 



" " Lime 86.42 



" " Magnesia 4.24 



Sulphate of Lime 21 



Organic Matter 16 



Mining Methods. 



It will be seen from the above descriptions, that mining operations 

 have been mostly carried on in this region in an irregular and primitive 

 style. I requested Mr. John "VY. Harden to give me the benefit of his 

 large and varied experience as a mining engineer and superintendent, 

 both in the English and in the American collieries and iron mines, in 

 stating what ought to be the most economical mode of entering on and 

 exhausting the Nittany Valley limestone deposits. His recent success in 

 increasing the export of limonite from Pinegrove Furnace banks south of 

 Carlisle, by a judicious application of a system of regular approaches, 

 justifies me in placing a high value on any practical suggestions he has 

 to offer respecting similar deposits. 



He therefore visited the Pennington, Dry Hollow, Kerr & Bredin, 

 Pennsylvania Furnace, and other Banks above described; and the follow- 

 ing extracts from his report will show that there is but one conclusion to 

 arrive at, and that a very simple one ; viz., that the system to be almost 

 universally adopted is that by open-cuts, approached from the direc- 

 tion of the railway, at the lowest possible levels, and worked to the 

 right and left, in advancing slopes, one above the other ; that the deep 

 rich-ores should be worked at the same time with the upper wash-ores, 

 or not greatly in arrear of them, so that the wash-ore thus won may pay 

 the expenses of uncovering the richer lower ores; and that where surface 

 water is scarce, bore-holes should be sunk to serve the double purpose of 

 exploration and water supply. 



Whether additional and larger furnaces be erected in the Valley, or 

 whether the ores be sent by rail to the Iron Works in Eastern and 



