WILKESBARRE DISTRICT.
The accompanying illustration, Fig. 35, of the Wilkesbarre basins gives a good general impres sion of their form and features ; but it is by no means exact in proportion or measurement. It is an ideal section, formed from such data as were accessible. We may point out a few errors which those practically familiar with the district will detect. The number of basins between Wilkes barre and the mountain is uncertain, but they run deeper, in all probability, than the section indicates. Our artist, though very skilful, has transposed the seams, as may be noticed, in crossing the basin, and has placed more veins on the south than the north side. Otherwise, the illustration conveys as correct an impression of the coal basins in the Wilkesbarre district as can be furnished by the present state of their develop went.
For the information of those not familiar with the region, we may state that this view is from the west towards the east. Wilkesbarre is repre sented by a number of houses on the right or south side, and Kingston by a large house on the left or north side. The white dotted space between the two is intended to illustrate the erosion or denudation which has taken place generally in the vicinity of the river, to a con siderable depth, from this paint to Pittston.
The probable depth of the central portion of the basin is from 1000 to 1500 feet; and in localities between Wilkesbarre and Nanticoke the depth is undoubtedly greater. The first seam of any note cut in the Dundee shaft, which is nearly opposite Plymouth, is about 7( )0 feet from the surface. This vein is one of the upper ones, as shown in the accompanying vertical section, and must be nearly a thousand feet from the bottom of the basin at that point. The depth perhaps of the larger portion of the coal on each side of the central basins is within 750 feet of the surface.
In figure 36 we give the total thickness of the mea sures at about 1000 feet, including 10 veins of work-. able coal, with an aggregate thickness of from 80 to 100 feet. There is some doubt as to the thickness of the lower veins, particularly B and C, whose thickness we have not given. They are generally estimated to
be over 20 feet respectively; but we think they will eventually be found less. We are aware that the Mammoth, or E, folds over abruptly in some localities, and may be mistaken for an underlying vein ; but it will not be found at any considerable depth. This feature of the Mammoth or Baltimore vein is fully developed at the Hollenback mines, now operated by the Consolidated Company, where the slope on the seam abruptly terminates and the bed itself turns back at nearly the same angle. It would confuse and interrupt our deScription to explain this feature of inverted dips here, but in another place these irregularities of forma tion will be fully discussed and illustrated.
Prof. Rogers places the Baltimore bed E as the upper seam of his lower series, and the Pittston four teen-foot vein E as the lower bed of his upper series. This is evidently an error, as it is now positive that those two locally distinct names apply to the same vein, and that the Baltimore vein at Wilkesbarre is synony mous with the fourteen-feet vein at Pittston, while these are in turn identical with the Scranton G vein and the Mammoth or E of our nomenclature.
There is more uncertainty about the veins above the Baltimore bed, and some obscurity attending the seams below; but generally they can be recognized as identical with the seams at Scranton, or those of Mahanoy or Pottsville. We think it probable, however, that the " Primrose" at Wilkesbarre and Nanticoke is H rather than G, and that both F and G are between the Mammoth and Primrose at Wilkesbarre. It is known that two seams exist in most regions within this space, but one of them is generally so small as not to merit a position among workable veins. We should have placed all the seams, both small and large, in our vertical columns, instead of the workable seams only, if it had been possible to obtain the necessary data. In the Pottsville column will be found most of the small intervening seams, which will be noticed particularly from the fact of their not being lettered or named.