94 F\ REPORT OF PROGRESS. E. W. CLAYPOLE. 



A hundred and sixty feet of shale, mostly greenish, over- 

 lie this, and are in turn overlain by the ore sandrock % a 

 double bed of sandstone about ten feet thick, containing 

 between its two portions a thin bed of hard ore. 



Upon the sandrock lies the great source of all the Mil- 

 lerstown ore, the sand vein ore bed, about twelve inches 

 thick. 



The mining industry at Millerstown is of comparatively 

 recent date, little having been taken out before 1866. I have 

 been told, however, that a small quantity was used at the 

 old Juniata furnace more than 40 years ago. Since then, 

 however, several hundred thousand tons have been sent to 

 Reading, Harrisbnrg, Dry Valley, and Lochiel where it 

 takes high rank among iron ores. It is said to yield a very 

 tough iron. 



One fact connected with these beds is well known by all 

 engaged in mining or seeking ore, because it has a most 

 important influence upon the quantity that can be obtained 

 in any given area. The fossil ore is only soft to a certain 

 depth, or to the depth to which the surface water penetrates. 

 Below that it is a hard ferriferous limestone, useless for the 

 furnace. In the slopes of the mountains, where the drain- 

 age soaks down, the hard limestone — the original ore-bed — 

 has been altered by the removal of the lime and perhaps by 

 the concentration of iron, so that its texture is softened and 

 its proportion of ore relatively, if not absolutely, increased 

 and it is rendered valuable as an ore. But below this level, 

 and probably in most of the flat land, nothing would be 

 found but the hard limestone above mentioned. This fact 

 is sometimes overlooked in estimating the quantity of iron 

 ore and the consequent value of the land containing or 

 supposed to contain it. In fact the sand vein ore bed and 

 the other-underlying fossil ore beds are in all probability 

 nearly worthless, except along the slope of the ridge where 

 they cro]) out. Even there, in some places, the hard, lime- 

 stone is found. Mr. R. Cochran has recently cut it in a 

 drift opened about a mile west from Millerstown and where 

 the expense of mining far exceeds the value of the ore. 



A determination of the principal ingredients of the hard 



