Nos. VI and VII are pretty generally concealed. The No. VIII, the Marcellus black slate, shows just north of the school house on a 60° S. E. dip, indicating the rather stiff inclination of the north leg of the Northumberland synclinal, and permitting successively higher members of this formation to come in rather rapidly towards the Snyder county line. The upper divisions, Portage and Chemung, are however not well exposed.
Limestone quarries.
The Winfield limestone quarries of the Union Furnace Company are situated at the east end of the limestone ridge, a short distance south of the furnace with which it is connected by a short railroad siding. They are the most extensively worked quarries in the county and the only ones having direct railroad connection. There are 12 set-kilns, with a capacity of 800 bushels of burnt lime, and which require about 3 weeks on an average to burn out. There are in addition 4 draw-kilns, which yield 75 bushels each 24 hours, so that the daily output of burnt lime here, when all the kilns are active, is about 750 bushels. All the plaster lime is drawn from the set-kilns, which appear to make a more even and thoroughly burnt product. The draw-kilns are used for farm lime. The lime burned at these kilns has justly gained a high reputation.
A compiled section showing in all about 115′ of No. VI shows the following sub-divisions at this quarry:
| Shaly limestone, | 6′ | 62′ | ||
| Thin limestone beds from 10″ to 3′, | 27′ | |||
| Massive bed; seamy, | 8′ | |||
| Massive blue limestone; solid, | 5′ | |||
| Greyish limestone in small beds, | 8′ | |||
| White and blue limestone in beds 1′ thick, | 6′ | |||
| Shelly limestone rock, | 6′ | 6′ | ||
| Small beds from 3″–1″ thick, | 5′ | 48′ | ||
| Good blue bed, | 2′ | 6″ | ||
| Small beds, | 7′ | |||
| Smooth blue limestone; a thin slate in center, | 8′ | |||
| Small beds, | 7′ | |||
| Good blue limestone, | 3′ | |||
| Small beds from 6″ to 1′ thick, | 16′ | |||
| Slate. |
