Fig. 20.-General Section across the Appalachian chain from the Valley of the Ohio to the Atlantic.

Unaltered Coal-measures.

Altered Coal, and Carb. Limestone overlying Devonian Schists.

Porphyry. Schists. Syenite.

Auriferous belt.

Oolitic Coal-field.

Richmond.

of Otter. Thus it appears that the most highly altered rocks are not those that have been most elevated; but, as already suggested, these latter having been pushed through the others on a line of elevation of great length, have squeezed and contorted, and partly disturbed the carboniferous series near contact on the east side. The same elevation has also brought up to its present position all the rest of that vast range of these deposits which extends westwards to the Mississippi. The rocks, squeezed and contorted towards the east, and there partially covered up with deposits of newer date, have also undergone a certain amount of chemical change, resulting in the production of the narrow, elongated and highly-inclined anthracitic basins of Pennsylvania.

The course of James River from Lynchburg continues for about fifty miles parallel with the axis of elevation of the Blue Ridge, and distant from it about twenty miles. The rocks, whereever seen, are schistose and quartzy, and dip considerably towards the east, with more or less local variation. Further down, the river takes an easterly direction, and lays bare fine gneissic or granitic rocks, which appear to be somewhat extensively quarried for building purposes. The decomposition of these rocks by the weather results in the production of a fine and abundant soil, more richly and deeply coloured with oxide of iron than I remember to have seen elsewhere. No doubt there exist in the gneiss considerable veins of oxide of iron, and it is probable that the gold found in the district, and at present extensively mined, has been obtained from these irony and perhaps quartzy veins in granitic rock. The accompanying section (fig. 20) may assist in illustrating the preceding and subsequent account of this singular and interesting range; but it

would require a series of engravings, and a long and minute description, to convey to the reader any adequate account of the condition of the rocks. The crests of the range are seen to bring out the metamorphic and igneous rocks towards the east, as already described.

Leaving James River at the town of Columbia, where there is a remarkable development of the oxide of iron, I entered at once the gold district, proceeding first to the Waller Mines, a distance of about ten or twelve miles to the north, my route crossing in a slanting direction the chief auriferous belt. For the greater part of the way the road runs through cleared agricultural land, a small tract of original forest greatly thinned, and a good deal of land once cultivated, but now left to become forest once more. In winter I found it bad enough, but no doubt it is very passable in summer.

A mine belonging to Commodore Stockton, now much worked, is about nine miles to the north-east of Columbia, and is entirely in land once cleared, exhausted by repeated crops, and since left for the wood to grow again. All the wood is very small. The veins are considered to be rich, and the principal one (Stockton's Vein) is worked to some depth. It is said, however, that the expenses of putting up machinery and managing the mine have not yet been returned. The contrivances, as far as I could see on riding through the property, were rather rough. Both here and in the neighbourhood of the Waller Mine, and indeed for some distance before reaching these mines, I saw abundant evidence on the road-side that not only had the streams and river-beds been washed for gold, but that a large quantity of white quartz rock had been crushed. The fields and road abound with large quartz fragments resembling boulders, and the ground is everywhere of the brightest vermilion red.

On the Waller estate I found that in the lower part, towards the south-east, the country consists of a very hard tough hornblendic schist, striking north-east and south-west, dipping at a very high angle to the south-east, and intersected by strong and well-marked joints bearing north-west and southeast. Between this rock and a fine granite, or rather syenite, which comes out abundantly at some distance towards the north-west, there appears to be a broken and varied series of quartz veins and soft broken schists, often highly micaceous, and

everywhere deeply impregnated with peroxide of iron. These sometimes alternate with veins of highly pyritous grit arranged in bands nearly vertical, which are parallel on the whole to the strike of the hard hornblende schists, and are also either parallel or nearly so to each other. Of these there are on the property three distinct groups of bands or veins, all auriferous, and very rich in gold in certain places. Washings were formerly carried on successfully in a small gully running through the estate, and on searching for the veins whence the auriferous sands had been removed, they were found distinctly marked close to the surface.

The first vein seen in ascending from the brook (Peter's Creek) is known as the Waller Vein, and here ranges west-south-west and east-north-east, being nearly vertical, but slightly underlying east-south-east, and very soft. It has been much and profitably worked to a depth of about thirty-five feet, when the necessity of pumping stopped operations. The surface has been worked to some distance near where the shaft was sunk. At a very short distance beyond, the Goochland Vein is shown by an open cutting, and is found to be a hard quartz lode bearing north-east and south-west, dipping south-east, and cutting the Waller Vein near the shaft where the largest quantity of gold was found. Still further up towards the north-west, another powerful quartz lode shows itself at the surface, but has not been opened. This is apparently parallel with the Goochland and crosses the Waller at no great distance. The Goochland vein underlies at a greater angle than the Waller, and the underlie of the other quartz vein is not known.

Between this group and that in the north-western part of the estate, there are a few costeaning-pits, and it is certain that quartzy and auriferous veins exist. Towards this north-western extremity is another group well-marked, but not so valuable at present as the Waller. It consists of five lodes, two corresponding with the Tellurium veins' elsewhere worked with advantage; one consisting of quartz, but presenting the appearance of a sandstone, and hence called the Sandstone Vein; and two of white tabular quartz, the Richmond and Moss Veins. Of these, the former seem to bear east-north-east and the latter north-east, both underlying south-east; but they are not very distinctly marked.

The tellurium veins' are close together, in a highly ferruginous micaceous schist extremely soft. The quartz of which they consist is hyaline, often tinted greenish or brownish, and between or near the band of quartz there is a very promisinglooking band of pyrites. These veins are cut at about 25 feet down; and, as a general rule, I was informed that the lodes, of whatever kind, have rarely been found rich at or very near the surface. They have also been found to retain their value at all depths at which they have been hitherto reached.

An auriferous vein has been found in the rocks that occur south-east of the Waller property, but this is the last in this direction, as at present known; and there is also one, and one only hitherto determined, to the north-west, connected with the rocks of this district. Some few miles further west other lodes are known, but they have been little worked in Fluvanna county. Other veins at Tolersville to the north seem to be in rather different condition.

The general character of the so-called veins in this part of the country is that of irregular quartzy bands, varying in thickness from half an inch to several feet, enclosed in a highly ferruginous rotten schist, often having large plates of mica extremely rotten, and passing into a kind of marly sandstone of loose texture. Where the rock is of average quality, as it is considered to be in the best veins, the work may be carried on with the certainty of finding gold throughout great thickness of mineral, but in other cases the expenses of working are apt to swallow up all the profits, however large they may be, that arise from occasional rich portions, whether in shoots or nests.

I am inclined to believe, from what I have seen in this part of the mining district, that the whole of the so-called quartz and other veins are really nothing more than nearly parallel bands occupying a definite position, forming part of the great series of altered rocks on the eastern side of the great axis of the Appalachian chain, and dipping at a high angle away from that chain, throughout the whole country, from the State of Maryland to the final dying away of the axis in Georgia. To say that there are large alternating bands of hornblendic rock, quartz, and schists, describes this series in a general way. Hornblendic porphyry commences at the Blue Ridge, and is succeeded by a wide range of schists, occasionally, as near Charlottesville,

mineralized with copper and lead. Then succeeds a broad band of syenite; and next, beyond it, towards the Atlantic, appears a band of mixed talcose and micaceous schists; then hornblendic schists, sometimes very hard, sometimes extremely soft; rotten sand, intensely coloured with oxide of iron; quartz bands, varying in thickness from a quarter of an inch to several feet; garnet schists; highly pyritous bands, sometimes compact, but readily decomposing; soft dark blue talcose slates; pale yellow clayslates, and perhaps other materials. These are probably all more or less auriferous, but certain parts, and certain mineral combinations, seem to contain much more gold than others. All these bands range in a north-east and south-west direction, dipping to the south-east at an angle varying from 45° to the vertical. Locally, the direction of the quartz or other hard bands undergoes change; and it is found that the coming together of two bands, or the presence of particular minerals, as oxide of iron or garnets, is favourable for the presence of more gold than usual, in small shoots or pipes, which occasionally are not only rich, but numerous and extensive. Lumps of gold weighing twenty ounces have been found, and from single nests gold to the value of from £500 to £2000 has frequently been extracted. Where, however, these richer portions are found, the average of the rock or vein is generally not increased, and perhaps the most favourable conjuncture is where several bands or veins usually bearing gold come near together, so that two, three, or more of them can be worked without inconvenience from a single shaft. The gold is either disseminated through very frangible quartz, spread in spangles on more hyaline and harder quartz, deposited in narrow crevices in soft blackish or red irony sandstones, disseminated in grains and small pepites in soft and micaceous irony sand, or spread undistinguishably through a mixed mass of sand, blue slate, pale yellow slate or schist, and hyaline quartz*.

Returning to Columbia, and thence proceeding up the

* Since writing the above, I have had an opportunity of examining a carefully-drawn geological section through one of the richest gold-bearing districts of California (that of Grass Valley). There is here the same alternation of hornblendic schists and syenites with quartz bands, the whole decomposed near the surface, and yielding much gold near the hard rock.