Detached masses or patches of cemented gravel are found on the summits of a few mounds or spurs of hills in this basin. These patches,. on account of their hardness, seem to have resisted the disintegrating influences of air and water, which have swept away and scattered the original deposit of which they formed a part, depositing the released gold in the adjacent gulches and streams and over the flat. They are but isolated monuments, indicating the existence, ages since, of an extensive belt of gravel deposited by the action of water, but whether in the channel of a running stream, or in a lake-like depression, or whether these deposits. were formed from the "wash" of the ancient river now covered by the lava of Table Mountain, (which is probably the case,) cannot be ascertained without close observation and patient investigation. One of these patches, situated immediately to the east of the town, and about one hundred and eighty feet above the level of the basin, covers an area of about ten acres and proved exceedingly rich, most of the pay being found in a blue streak, varying from one to twenty inches in thickness and lying immediately above the bed-rock. The depth of the gravel in this tract did not exceed thirty feet, and the best surface-diggings of the vicinity were found on the slope to the east of this mound and in the bed of Wood's Creek. These detached masses of gravel are said to extend southerly into Mariposa County, where they exist in larger bodies, and will be worked immediately on the completion of several ditches now in process of construction. Toward the north we find the great surface deposits of the limestone belt which probably owe its origin to the

same causes.

The quartz ledges in the vicinity of the town are all supposed to be on the Mother lode, which lies immediately to the east. They are, beginning with the most southerly and proceeding north: The Clio, 10 stampsnot running for two years; Orcutt's mine (supposed to be on a spur of the Mother lode)-a very rich vein of decomposed quartz; Eagle, 10 stamps-operations suspended in mill pending completion of drain tunnel; the Shawmut-idle for two years; belongs to a Boston company and is closed on account of mismanagement and defective machinery. Two miles northerly from Chinese Camp, and on the edge of the same basin, is situated the decayed and deserted town of Montezuma, which was once noted for its rich placers. Wood's Crossing, on Wood's Creek, one mile south of Jamestown, is noted as being the first ground worked in the southern mines, early in 1848. The creek here was very rich, and was worked by the Indians, of whom there were many here at that time. It is said that the first traders who came into this part of the country bought gold-dust from the Indians in exchange for its weight in beads, raisins, &c.

Jamestown.-Between Montezuma and Jamestown the country is broken up by rolling hills of no great elevation. The Mother lode is intersected and cut half a mile south of Jamestown by Wood's Creek, a stream carrying but little water in the summer, but very turbulent in the rainy season. At this point the croppings of the lode have a width of from twelve to sixteen feet, compact and boldly defined, with numerous spurs and parallel veins on the east side, but the quartz is barren at the surface. These parallel veins have proved very rich but not continuous. Abandoned excavations and tunnels show that they have been followed till they "pinched out" or became merged in the main lode. Near here, on the line of the Mother lode, are situated Quartz Mountain and Whisky Hill, famous for both rich quartz mines and great failures. The most noted mines are the Golden Rule, the App mine, the Heslep mine, and the property of Rosencrans, Preston & Co. on Whisky Hill.

About one mile and a half west of Jamestown the Mother lode has been crossed by the lava flow of Table Mountain, and makes its appearance again in prominent croppings on the west side of the mountain at the Rawhide mine, one of the oldest locations in the county.

The past history of Jamestown is that of all mining towns relying mainly on placer diggings-a hasty growth and a slow but sure decay. The placers in this vicinity and the bed of Wood's Creek were of great richness, and for a few years the sales of gold-dust averaged nearly $1,000 per day. The placers were of the same character as those of Chinese Camp, rarely exceeding two feet in depth, and have been worked over several times. The present population does not exceed three hundred. The future of the town depends on the quartz-mining on the Mother lode and the opening of the old channel underlying Table Mountain. Both of these classes of mining require large expenditures, but promise large and profitable returns.

Quartz Mountain is a cone-shaped hill rising abruptly to a height of four or five hundred feet from a rolling country. Its isolated position makes it a prominent landmark for miles around, this prominence being greatly enhanced by an immense cropping of quartz which crosses the summit of the mountain on the line of the Mother lode, and at a distance presents the appearance of a great wall. Most of the mines are opened about half way between the base and the summit. The veinmatter here seems to have widened with the expansion of the mountain, and veins are found both on the foot-wall and the hanging-wall, separated by masses of broken slate and quartz, known as "horse-matter." These veins have a pitch to the east of eighty degrees.

The Heslep mine, on Quartz Mountain, probably the most thoroughly developed mine on Quartz Mountain, is a location of 1,555 feet on the hanging wall of the lode. The mine was opened in 1852, and was then This cut has worked by an open cut on the face of the ledge. been continued for nearly 100 feet, and a tunnel run from its face, on the ledge, a distance of 600 feet. Winzes have been sunk from the floor of this tunnel to a depth of 65 feet and a new level opened. On this level the vein is 14 feet wide; 8 feet of this vein-matter is hard white quartz, and 6 feet are a mixture of soft slate and broken quartz, highly sulphureted. The foot-wall of the vein is greenstone and the hanging-wall slate. The average pay of this mine, which may be taken as a fair representative of the mines on Quartz Mountain, is about ten dollars per ton for rock taken from the tunnel, and a slight advance for rock from the lower level. This is exclusive of specimen rock, which is now often encountered as depth in the mountain is attained. The pay runs in chutes or chimneys which rarely exceed 100 feet in length, but several are found on the line of the location. The softer material can be mined and milled at an expense of $3 per ton. Of this class of rock large reserves are in sight on the surface which can be cut down on an open face and run through the mill in large quantities, with a profit of $3 to $5 per ton without interfering with the development of the mine. The property is owned and managed by Mr. B. F. Heslep, and is an example of prudent and skillful management. He has commenced sinking a shaft from the surface to connect with the winze from the tunnel, and on its completion will open a new level 160 feet below the tunnel, or 300 feet in depth from the surface. The mill has fifteen stamps of 650 pounds, with a crushing capacity of eighteen or twenty tons per day, and is run by an overshot wheel forty feet in diameter, supplied with water all the year, at an expense of $140 per week, night and day. The mill is built for

thirty stamps, and the other fifteen will be put in as soon as the shaft is sunk and the lower level opened. The mill, situated a short distance below the mouth of the tunnel, is provided with Stanford's self-feeding apparatus, requiring only one man to attend to the fifteen stamps. No pans are used, as the main reliance is on the free gold. The sulphurets are preserved for future treatment.

The App mine next adjoining and parallel on the east is owned by Griffin & Co. The ledge is 1,000 feet long, and from 15 to 30 feet wide. They have a 25-stamp mill, but it has only been run at intervals during past year. Their rock will run from $15 to $20 per ton. They have a shaft down 580 feet, on an incline of 60°. The hoisting-works are very complete, and run by an engine of 25 horse-power.

The Knox mine, one-half mile from the Heslep, is 1,200 feet in length, with a vein 10 to 20 inches in width. It is owned by Preston & Co. They have hoisting-works run by a 30 horse-power engine, and a mill of ten stamps and two arrastras, now crushing ten tons per day. The quartz yields an average of $30 per ton exclusive of sulphurets.

The Golden Rule, near Poverty Hill, is owned by a San Francisco company. Their mill of 15 stamps is run by water-power, (50-foot wheel,) and will crush 15 tons per day (24 hours,) which average $10 per ton. A tunnel 500 feet in length is run in on a grade with the mill, to which the rock is brought by car. This tunnel runs nearly east. At this point, the tunnel runs south 75 feet, where their hoisting-works are situated, 87 feet underground. The hoisting-works are run by an engine of 12 horse-power. At the hoisting-works there is a vertical shaft 225 feet deep from the surface. The hanging-wall is of serpentine, and the foot-wall of slate formation. The vein is from 7 to 9 feet wide. The Golden Rule has not been worked regularly during the year 1871, and no dividends were paid.

Table Mountain.-This remarkable remnant of the basaltic overflow overlies, as is well known, the ancient channel of auriferous gravel. The accompanying diagram is made from observations with a Green's barometer, and shows the interesting fact that the rim-rock of the ancient river is higher on the west side than on the east. The difference is 33 feet.

The observation taken at A was made at the hoisting-works of the Table Mountain Co.'s claim, on the eastern side of Table Mountain, (formerly known as the "Humbug" claim,) 87 feet above the rim-rock of the ancient river, covered by the lava-flow known as Table Mountain; elevation, 1,680 feet.

Observation B was made at the hoisting-works of Hughes' mine, on the west side of the mountain (formerly known as the Maine Boys' tunnel) 110 feet above the rim rock of the ancient channel; elevation 1,736 feet. This claim is next adjoining and south of the Table Mountain Tunnel Co.'s ground.

Observation C was taken on the summit or plane of Table Mountain and at a point equidistant from observations A and B; elevation 1,882 feet.

The diagram, a cross-section of Table Mountain, is a representation

of the stratification at this point: a is the basaltic lava rising in precipitous cliffs from the surrounding country; b a stratum of compact sand nearly hard enough to be designated as sandstone; underneath this is a layer of gravel, represented by c; and o shows the position of the auriferous gravel.

The auriferous gravel is extracted by means of inclines running respectively from A and B to the bottom of the channel.

Mining in Table Mountain.-The ground of the "Table Mountain Tunnel Company" is situated on Humbug Flat, about one mile north of Jamestown on the east slope of Table Mountain. The company own 4,500 feet of ground, north and south on channel, and claim from base to base of the mountain. Their gravel deposit is partly under the lava capping, but a large portion of the best ground lay to the east of the lava flow and seemed to owe its origin to a deflection of the ancient river channel, which here took a slight bend, followed by the lava stream, leaving exposed a large portion of the old river bed. The ground was first worked in 1852 by a tunnel running from Peppermint Creek, an insignificant stream on the east side of Table Mountain. This tunnel was run 1,000 feet in slate bed-rock, and on rising twentyfive feet pay gravel was struck near the rim of the channel. This tunnel cost $60,000, and ruined its projectors, only four of them holding a small interest when pay was struck. Subsequently the ground was opened by inclines higher up the slope and near the edge of the lava capping of the mountain, and is still worked by this method, the Peppermint Creek tunnel being used for drainage. Drifts are run from these inclines by means of which the ground has been breasted out for a length of 2,500 feet, and 2,000 feet yet remain to be opened. The channel of the old river proved to be from 100 to 150 feet in width, and the breasts were opened to a width of 30 to 80 feet according to the yield of the gravel. The thickness of the pay gravel varies from four to six feet-the richest being on the bed-rock, which is "picked” down to a depth of ten or twelve inches. The main incline, through which the mine is now worked, is 320 feet in length, the perpendicular depth from the bottom of the incline to the surface being eighty-seven feet. The strata passed through in running this incline were compacted sand alternated with thin layers of "pipe-clay." Underneath this was found the pay gravel-four to six feet in thickness, then a soft slate bed-rock. The main north drift is now 1,600 feet in length on the channel, but "breasting" has not been made on more than half this distance. The gravel is brought from the "head" or "breasts" of the drifts by a car drawn by a mule to the foot of the incline, whence it is raised to the surface and emptied in a large dump-box.

The method of treatment here is by the "Cox pan," a process which is fully described in another part of this report. The hoisting-works and mill are run by eighty inches of water, by means of an overshot wheel thirty feet in diameter. A test of several hundred car-loads of gravel at this mine showed a yield of five to six dollars per car-load, equivalent to $10 per cubic yard; but this "run" was on very rich ground. The average yield for a run of several successive months would probably not exceed half the amount obtained when the test was made, and with this yield a large profit accrues to the owners. gravel of this part of the channel of Table Mountain is soft and easily extracted with the pick. In using the "pan" the gravel is fed continuously from a "hopper," the feeding being interrupted only long enough to discharge the bowlders from the mill or pan. The dirt released by the action of the pan passes through the apertures in the bottom,

The

whence it runs through three hundred feet of sluice-boxes, and the proprietors. are confident from experimental tests that they save as much of the gold as by any process in use. They speak highly of the "Cox pan" after two years of constant use.

The Hughes mine, comprising the ground formerly known as the Maine Boys' tunnel, one of the earliest locations on Table Mountain, is situated north of, and next adjoining the claim above described, but is opened from the western instead of the eastern face of the mountain, which is here nearly 2,000 feet in width. The main drifts of the two companies are now approaching each other, one running north and the other south on the channel, and before the close of the present year the communication will be opened through the mountain under the lava crust which filled the ancient channel of Table Mountain. This will afford complete ventilation for both mines, and greatly facilitate future explorations. Barometrical observations taken on a line across Table Mountain at this point give the following results:

Altitude above sea level.

Mouth of Table Mountain Company's incline, east side Table Mountain..
Mouth of Hughes's incline, west side Table Mountain..
Summit, or plane Table Mountain between these points..

1,680 feet.

1,736 feet.

1,882 feet.

It will be observed that the rim rock of the old river bed is thirtythree feet higher on the western than on the eastern side, showing that the river wore its deeper channel on the western side. The bottom of the river (bed-rock) seems to be about 300 feet below the plane of the mountain. It is an interesting question which we submit to the consideration of the State geological survey, whether these facts have any bearing on the great distribution of gold on the eastern side of the mountain as manifested on the limestone belt from Columbia at Kincaid Flat, and in the bed of Wood's Creek. The Maine Boys' ground, after many vicissitudes of good and bad fortune for nearly twenty years, passed into the hands of its present energetic owner, Mr, David Hughes, who has demonstrated that this class of mining can be carried on with uniform profit when managed with economy and skill. Mr. Hughes owns 1,900 feet on the channel, and his ground is opened by an incline four hundred and ninety-six feet in length, and 110 feet in perpendicular depth. The width of the channel varies from 150 to 300 feet, while the pay-dirt varies from thirty feet to the entire width of the channel. The gravel is about twenty feet in thickness, but the paying portion seldom exceeds four feet on the bottom. The stratification is the same as on the other side of the mountain. Several "channels" are supposed to exist in the claim, but they are probably the results of the changing of the river bed from east to west as demonstrated by the barometrical observations above noted. The claim is worked through two tunnels, the drifts in one (the old Maine Boys') being 2,600 feet in length, in the other 1,500 feet. The gravel is taken out and hoisted in the same manner as in the claim last described. Mr. Hughes uses two "Cox pans," run with fifty inches of water by an overshot wheel thirty feet in diameter. Each pan will treat forty car-loads of gravel per day-one ton to the car-load. The gravel is fed continuously as at the Table Mountain Co.'s mill, about ten inches of gravel being kept constantly in the bottom of the pan, but it is here charged with a small quantity of quicksilver. From one hundred to two hundred feet of sluices are used below the pans. The yield is from $2 50 to $3 per car-load, and is considered good pay. The gravel sometimes yields much higher, rarely lower. This is a little less than $5 per cubic yard. Mr. Hughes has used these pans for several years in succession, and has made several improvements in their construction