Annual Production and Shipments of Coal from the Richmond Coal Basin, in Tons of 2,000 Pounds.

1850

35,937

36,000. "

57,051

9,029.16

128,988.

138,017.16

1851

27,531

17,432.40

43,000. "

39,619

8,940.74

127,582.40

136,523.14

1852

21,752

34,955.25

43,000. "

6,979.49

99,707.25

106,686.74

1853

21,098

15,620.69

58,352.

6,654.97

95,070.69

101,725,66

115,494.69 Miscellaneous transportation, estimated by hauling in wagons,

same specimen, as well as in large benches, three varieties exist, which are also noticed in other coal fields.

1. Glance coal, of a deep black color, vitreous lustre, and great brittleness; appears like pitch, in thick strata.

2. Lamellar coal. Grayish-black, or brownish-black, of a dull resinous lustre, much tougher, generally in thin strata.

3. Fibrous coal. A natural mineral charcoal; occurs in very thin film-like layers between the former, also in the form of small pieces; it is much like compressed dust. According to the investigations of Dr. A. Schondorff, in the coal fields of Saarbrucken, the average composition of these varieties is as follows:

It will be readily perceived that even if much of the fibrous coal should occur, washing will reduce the amount of ash, the fibrous coal being the highest in ash.

This field yielding an excellent gas coal, as well as coking coal, steam coal, and blacksmith coal, its revival in the markets of the United States, which it commanded before the late civil war, will only be a matter of time, because its accessibility to sea-going vessels of 500 to 1000 tons' capacity will fairly counterbalance the moderate cost encountered by deep mining. The average distance from the principal mines now to James River navigation at Richmond, or Osborn's, or Port Walthall below it, is only 13 and 24 miles respectively.

The same coal, but of an inferior character, being very much contaminated with iron pyrites, has been mined near Farmville. Several seams from one and a half to six and a half feet have been partially explored. It has also been found in that part of the western belt extending into North Carolina from Danville.

Although no coal has yet been found in the largest belt in this State, namely the Potomac deposits, it is a matter worthy of inquiry, why should coal not exist in this same formation in so extensive a deposit, when it is found in such small patches as the Deep Run, the Farmville, and in the extreme southern end of the belt in the Dan River deposits? The foregoing may serve as a guide in the investigation of this question. The vital importance of a discovery

of coal here can readily be seen by noting the geographical position of the belt, in close proximity to the seat of government, and to excellent deposits of iron ore, which could be reached by railroad improvements already established.

As has been said formerly, no iron ores, at least in sufficient quantity for practical purposes, have so far been discovered in the Richmond deposits. But since the coal would furnish a good fuel after proper preparation, it is of importance to look for the other important material for the manufacture of iron. This could be at present found upon two lines of public improvement. The first and most important will be along the James River and Kanawha Canal, upon the liue of which, or close to it, brown and red hematites, specular and magnetic iron ores of excellent quality, from within 50 to 180 miles above the coal-bearing rocks, can be mined in large quantities, at low prices. Upon that line very good limestone can also be obtained at very low cost. The line of the James River would therefore be the most available for the manufacture of iron, at a reasonable cost, along the northern part of the basin. Upon the line of the Richmond and Danville Railroad, in connection with the Mississippi, Atlantic and Ohio Railroad, or the projected branch into the counties of Henry, Patrick, and Franklin, are found excellent specular and magnetic iron ores, which would supply the middle and southern part of the basin, although probably at a little higher cost, according to freight charges.

Another material of economical value may be found in the fireclay and shale, which would form an important item in ceramic manufactures. As various qualities, from a light yellowish-gray, or nearly white, to those of red color are found, the manufacture of pottery, firebrick, or common brick and terra cotta, in connection with a low-priced fuel, would be remunerative, and at the same time furnish a new source for the use of coal.

The sandstones of this formation have been used for building purposes, and if selected with proper care, furnish a sufficiently firm material. It is necessary to avoid those in which the feldspar has a great tendency to decomposition, as they will weather and decay more rapidly. Where some of the thicker strata of limestone approach the outcrop use could be made of the same, although, so far, no attention has been paid to it.

A great source of lighting and lubricating material is stored away for future generations in the highly bituminous slates, which frequently occur in very heavy strata, and near the surface. As long

VOL. VI.-18

as the petroleum wells furnish this material at so low a price, of course no attempt to compete with them could be successful. But, nevertheless, a test of their real value in carburetted compounds would be a matter of great interest.

The pyritiferous slates, such as occur in this formation, would be used in other countries probably for the manufacture of copperas, alum, etc., as, for example, at Pardubitz, in Bohemia, while here they will for a long time to come only be a source of nuisance.

In concluding this paper I can only heartily echo the expressions of Mr. Macfarlane in "The Coal Regions of America," namely: "We have often turned with a sort of wonder to regard the Richmond coal basin. Its history is very strange. It was one of the earliest opened by the miner. It is the solitary one at tide-water, and near a State capital. It contains several beds of coal, and one of these is sometimes of great thickness; it is mined by shafts, on the English plan, and affords a variety of fuels, ranging from gas coal to native coke. One would have expected its complete development long ere this," etc.

The following statistics from the same volume show how slow its development has been:

While the Northern States have kept pace with the times, the Southern States have remained stationary, being satisfied to rest upon the laurels of their forefathers. Therefore this oldest of our coal fields is yet to see its best days.

Imperfect as this present description of the Mesozoic formation must be, it would be gratifying to the author if such practical researches as have been embodied in this paper would be followed up to a thorough and complete knowledge of this formation, which may yet be of great value to the eastern part of the State of Virginia.

PHILADELPHIA, February 21st, 1878.

COPPER MINING ON LAKE SUPERIOR.

BY PROFESSOR T. EGLESTON, PH.D., SCHOOL OF MINES, COLUMBIA
COLLEGE, NEW YORK CITY.

(Read at the Amenia Meeting, October, 1877.)

THE copper-bearing rocks of Lake Superior are composed of a series of metamorphic rocks, comprised under the names of amygdaloid and conglomerate, in which the copper and silver found with them are pseudomorphs. These rocks, generally, have well-defined walls which cause them to separate easily. Generally, the country rock is sterile, but it occasionally rises into the copper-bearing rock, and then carries copper. Usually, the amygdaloids carry copper, and the greenstones or melaphyres which encase them do not.

There is a very generally received opinion that the copper in these beds occurs in shoots. This does not appear to be proved, though the opinion seems to have some foundation from the experience of the Calumet & Hecla Mine, where a body of poor rock has been left, which, on the mine map, shows a general direction. The theory may be true of that individual mine, but too little work has been done in the other mines to draw any decided conclusion. The copper is very unequally disseminated in the rock, if any given piece be taken as an example, but, if the whole copper-bearing series be considered, its distribution is uniform. It may prove that there are certain directions in which the copper has been deposited more abundantly than in others, and these may be found to correspond with certain geological causes, but up to the present time the knowledge gained is not sufficient to warrant any general conclusion.

These rocks are supplemented by a series of true fissure veins, of which there are several systems, making the amount of native copper very large. Unfortunately, except in the fissure veins, known as "mass-mines," the copper is so scattered through the rock, and is in such a fine state of division, that, although it is not always difficult to mine, it is always difficult to dress it sufficiently to make it

pay.

The metal is so uniformly distributed through these copper-bearing rocks that detached pieces, called "float," are found in digging on almost any land in the country. These pieces vary from very small fragments, weighing not more than a few ounces, up to many pounds. In one instance, in making an excavation for a cellar of a