104 NEW YORK STATE MUSEUM 
west of the headframe. Traveling away from the ore body to 
westward there is an increasing intensity in granitization of the 
Pochuck-Grenville until actual Pochuck granite is encountered (see 
plate 4). The foctwall dips about 20° southeast; the hanging wall, 
much steeper, dips from 85° to 90° in the same direction. There is 
no sharp contact between the ore and the walls, since in both occur 
bands of magnetite interlaminated with biotite, so that in places the 
contact between ore and walls is indefinite and streaky. 
The ore. A granular magnetite, sometimes friable, but generally 
massive and firm, with included matters already mentioned. The 
height of the ore in the hanging wall side is from 100 to 120 feet; 
cn the footwall side it is about 80 feet, and the diameter or thickness, 
wall to wall, is about 60 feet at the center. The length of the horse 
from roof to tip is about 65 feet on the hanging wall side, and the 
width or thickness approximately 50 feet. ! 
The ore body pitches northeasterly at an average angle of 18° to 
19°, but the pitch varies from 12° to 36° in places. The inclined 
shaft, or slope, follows the footwall down the pitch, the lower corner 
of the slope always being kept in the footwall, as a guide to direction. 
The slope has been sunk 4500 feet on the incline up to the present 
time, with the ore constant in behavior. 
Owing to the large size and height of the ore body it is not 
possible to remove all of it. Every 60 feet pillars of ore, from 50 
to 60 feet long, are left to support the roof. Nor is all the ore 
cleaned away from the hanging wall in the upper lobe; some of it is 
left to support the wall, and some ore is left to support the roofs 
of both lobes or wings, so the actual structure in the roofs of the 
lobes is not known. It is probable that 30 or 40 per cent of the ore 
is left in the mine to serve as supports. 
The ore is hoisted in 2-ton end-dumping skips whose doors are 
mechanically tripped at the headframe, where it is taken care of by 
the usual arrangement of crushers, conveyors and storage bins. A 
steam tramroad 3 miles long carries the ore from the mine to its 
terminus; thence the ore is loaded into the buckets of an aerial 
conveyor 6300 feet long, which carries it to the dock at Fort 
Montgomery, on the Hudson river, where there is a storage bin of 
1000 tons capacity. The ore is shipped to Perryville, Pa., and other 
Lehigh furnaces. 
Under the old management water power was used in operating 
the plant, and such power, derived from the mine pond, is still used 
for running an old Cornish pump situated at the head of a vertical 
