The following is a description of the Wood Mine by William Glenn dated 16th September 1878, published in Persifor Frazer’s, The Geology of Lancaster County, Second Geological Survey (1890):
The Wood Pit was opened in 1828, and has worked to the present, except from 1868 to 1873. The total output has been about 95,000 tons of chrome iron ore. Of late years but a small froce has been employed, producing 500 to 600 tons of ore yearly. The assay value varies as with other kinds or ore, but within smaller limits. Sample given Prof. Frazer in 1877 was 56% Cr2O3.
The country rock is serpentine. The ore body as proved is almost 50 fathoms [300 feet] long at its greatest extension. Depth proved to 120 fathoms [720 feet]. Pitch of the mine is from 40° to 60° under the horizon. The strike is nearly E. and W. at the outcrop and nearly N. and S. on lower levels. The width of the ore bearing rocks is from 10 to 35 feet, or may be taken generally at 20 feet. In this space occur the chrome ore and gangue (mostly serpentine and magnesite) which shows a general attempt at stratification conforming to strike and dip of the mine. But occassionally a branch of ore will stand vertically and extend itself into the footwall - or it may be horizontal and do the same thing.
The mine is worked by ordinary 10 fathom levels, winzes etc.
The power for pumping and hoisting is taken from the Octararo Creek, which is 100 fathoms [600 feet] from engine shaft. For hoisting, power is obtained from a 60 inch Turbine, under 10½ feet fall and transferred by a 6 inch hawser cable to proper machinery at the mine. For power for pumps, a wooden breastwheel 16 feet high by 18 feet long is used under 10½ feet fall. The motion is transferred by 6" x 8" wooden flatrod, 180 fathoms [1080 feet] to the engine shaft. There are two Cornish plunger lifts in the mine, with 10 inch columns. The lower and third lift is a 6 inch drawing lift arranged for sinking deeper. The mine makes from 60 gallons to 110 gallons per minute - depending on the season.
For business reasons, but a small force of men has been employed of late years. There is no reason to think they will not continue, as heretofore, to produce 500 tons to 600 tons yearly.
Prof Frazer also comments:
From 1869 to 1875 the mine was flooded with water. The ore is thrown out almost pure and without admixture of gangue.
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During the last three years Mr. Glenn has not had more than 35 men employed, and at the time of the visit (July 10, 1877) only 15 were occupied.
A steam pump was used to un-water the mine in 1875, but since then a simple water power pump has been operated which uses the water power of the Octararo Creek. The shaft which conveys the power from the creek to the pit mouth travels on friction rollers and is about ¼ mile (or 400 meters) in length. It works at present with a 4 foot stroke, but with a 5 foot stroke attachment (July 10, 1877).
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The pump is equivalent to a 60 horse power engine.
About 5% of the ore is crushed and washed, the remainder being pure enough to ship without crushing. It is transported in wagons 5 miles (or 8 kilometers) to the Rising Sun Station, on the P. & B. Central Railroad, at a cost of $1.50 per ton for the carting and $1.60 per ton for the freight, from there to Baltimore. No siding is laid down, because the present state of the tract is not large enough to require a siding. The locality is nearly on the direct line between Baltimore and Philadelphia, and about 50 miles (or 80.4 kilometers) from the former place.
The mine, Mr. Glenn states, at one time produced all the chrome in the world, and in busy times furnished 400 to 500 tons a month.
At present the heirs of Mr. Tyson get their ore from California, and the Wood Mine is used as a reservoir to offset the vicissitudes of so long a shipment.
Mr. Glenn now has in hand another chrome region which promises well.
The ore from the Wood mine is hoisted out by a horse whim, and also by a turbine and endless rope. |