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1,400 feet long-in one place 150 feet under the surface of the rim rock-constructed at a cost of $10,000, was first used for washing. The grade is 13 inches to 12 feet, but eight inches is considered preferable. The sluice in the tunnel is two feet wide at the bottom, 32 inches wide at the top, and two feet decp. The flaring are better than vertical sides for the passage of large boulders two or three feet through, thongh anything' over 150 pounds injures the sluice: Nearly all the gold is caught within 200 feet at the head of the sluice, where the bottom is covered with slat frames six feet long and one foot wide, with four frames to one sluice-box. The slats are boards an inch thick, “shod” with iron straps three-quarters of an inch thick and an inch and a half wide. All the sluice-boxes below the first 200 feet are paved with fir blocks eight inches thick. The first hundred feet of the sluice are cleaned up every evening, and the second hundred twice a week. This cleaning up keeps the riffles in good ordler, and requires half or three-quarters of an hour. There are 2,300 fect of 11-inch pipe and 150 of 7-inch pipe in use in the claim. The total yield has been $300,000.
NITRO-GLYCERINE.-The number of men now employed is 15; last year it it was 28. One of the chief difficulties in this claim is the removal of the of the stratum of pipe-clay which rests on the pay gravel and must be carried off in the sluice. It is too hard to be piped away, so it must be blasted into small pieces. Previous to this year powder was used, but now Mr. Swenson, one of the partners of this claim, and the pioneer manufacturer of nitro-glycerine in California, supplies that fluid, which is so much better than gunpowder that 15 men do more in 1867 than 28 did in 1866. The nitro-glycerine shatters the pipe-clay into a multitude of little pieces, whereas powder broke it into a few large ones; so, after a powder blast, thie miners had to reduce the large lumps with gads, for which there is now little use. It costs about $2 per pound, and is preferred by the miners after they once become accustomed to it. No accident has happened with it on this claim, although sometimes two or three dozen blasts are set off in a day. The smoke from it disappears sooner than that from powder, but it is more injurious.
About 400 inches of water are used in the North American claim for four or five days in the week.
Batu DISTRICT.—The following claims are in the Bath district, adjoining the Forest Hill district :
In the San Francisco claim no work has been done for a long time.
The Rip claim, 450 feet front, has a tunnel 450 feet long in the bed rock. From this tunnel a shaft has been raised to the Paragon sheet, which was worked from 1852 to 1858. The company are preparing to pipe away the front of the claim, and they intend to erect a mill next year. Work is continued meantime on the tunnel.
The Golden Gate Company have 180 feet front, and own half of a joint tunnel, 400 feet long, on the boundary line of the Rough Gold Company. They are are now working the blue gravel, and getting $5 per ton from it
, but they intend to work the Paragon sheet. They have a five-stamp mill, driven by a hurdygurdy wheel.
The Rough Gold Company have a frontage of only a few feet, but the claim grows wider as it goes back into the hill, and 400 feet back it is 200 feet wide. There is a tunnel 1,800 feet long, 150 feet under the Paragon sheet, which is now being worked; but the tunnel was located for the purpose of working tho blue gravel.
There is a 10-stamp mill, which was erected in 1866, and is now running steadily.
PARAGON.— The Paragon claim has a front of 250 feet, extends a mile and a half through the hill, and is 400 feet wide at the back. The pay stratum now
worked is a deposit of rusty gray gravel, four feet deep, resting on the blue gravel 100 feet deep, and covered by volcanic sand. The blue gravel immediately on the bed rock, as well as for 100 feet above, contains some gold, but not enough to offer much profit. The gray gravel contains $10 per ton, the gold being coarse, some of the pieces weighing two or three ounces, and others containing quartz attached.
Work was commenced on the claim in 1852, and the gravel was sluiced for 10 years. It was so tough, however, that it had to be washed repeatedly, and after all much of the clay escaped undissolved. At the first washing the yield was about $1 per ton, and the second, third, and fourth washings, made at intervals of a year, yielded each $2 per ton, and $1 per ton for the fifth, sixth, and seventh washings. Freezing and thawing slaked the cement more rapidly than did sun or rain. In 1864 a 20-stamp mill was built, and then the claim first began to prove its high value. The yield of the claim was $100,000 in 1866, half of it profit. The yield per ton in the mill is no more than it was in the sluice, but the dirt is now not so rich as it was before.
The gray gravel, or "sheet,” as it is called, has all been taken out for 1,600 feet front. The tunnel is in the middle of the claim in the blue gravel, 20 feet below the sheet. The pay dirt is breasted out on drifts, which run entirely across the claim, so that there are 400 feet of breast for the men to work at. The gravel becomes softer when exposed to the air, so the large breast gives the benefit of exposure, as well as of abundant room. At intervals of 30 feet a chute is made from the sheet down to the tunnel, for the purpose of throwing down the gravel; few timbers are used, and the roof falls down upon the blue gravel, close upon the heels of the miners. Two men are constantly employed repairing the tunnel, which would close up in a month, if neglected. The blue gravel swells very much in one stretch of 150 feet.
There is enough dirt in sight for four years' work. All the dirt is picked down.
The mill crushes 200 tons a week, and the expenses are $1,000 per week. Fifty men are employed : 32 miners; four carmen in the tunnel; two carmen outside; two tunnel menders; four feeders, and six others in and about the mill. Two men feed the 20 stamps, and two others pick out the large stones from the gravel.
The stamps weigh 700 pounds, have 75 drops per minute, and 13 inches fall.
The screen is punched with holes a sixteenth of an inch in diameter, but they soon wear larger.
Two tons of gravel are fed per hour to each five-stamp battery, and three inches of water run steadily into each mortar.
A quarter of a pound of quicksilver is put in every morning, and as much more every evening into each battery.
A flask of quicksilver is bought once in four months, implying the loss of 75 pounds in that period, or half a pound per day on an average, or one-quarter of all that is used. The retorting is done carefully, so the loss is in the sluice.
Below the mortars are Jenny Lind riffles, and below those hurdy-gurdy riffles. It is said the claim was sold in August, 1867, for $150,000.
OTHER BATH CLAIMS.—The Greek claim, 160 feet front, has lately been bought by the Paragon Company for $9,650. This claim paid well in front, but was not worked well; the tunnel closed up; the owners quarrelled, and then they sold out.
The New York claim, 200 feet front, has a sheet like that of the Paragon, save that it is on the bed rock. A tunnel was cut 1,800 feet long in the bed rock, at an expense of $15,000, but bad air proved very troublesome; the work was stopped before pay was reached; the tunnel closed up, and nothing has been done for three years.
The Sebastopol Company has a front of 1,000 feet, cut a tunnel 800 feet in very hard rock, found no pay, and stopped work in 1866, after spending $20,000.
DAMASCUS.—Damascus, twelve miles northeast of Forrest Hill, on the same divide, but on its north side, has the same slate bed rock, and a similar bed of blue cement, though there is no overlying red gravel.
The Damascus Company has a claim 500 feet in front, and 3,000 long, running into the hill. The blue cement is four feet thick, lies immediately on a soft talcose slate-bed rock, soft enough to pick, and is covered by 600 feet of volcanic sand; at least it is supposed to be sand, though no careful examination has been made of it. The richest part of the cement is within 15 inches of the bottom, but the largest nuggets of gold are found in the bed rock. The gold is mostly coarse, in long narrow pieces, and those found in the bed rock, like those found at Forest Hill, are frequently quite black.
The claim is opened by a tunnel, 450 feet long, of which distance 200 feet were passed before the rim had been pierced.
The tunnel runs nearly south-southeast, about the middle of the claim, and apparently in the middle of what was the channel of the ancient stream. The present supply of cement is obtained northeast of the tunnel, and the breast is about 200 feet, extending nearly half way across the claim. A pillar 20 feet wide is left standing alongside of the tunnel to protect it. A rail track is kept along the face of the breast, and after 20 feet have been breasted out, the track is relaid for convenience of loading. The tunnel is eight feet below tły bed of the channel, and the load in the breast car is dumped into the tunnel car.
There are many large quartz boulders, some of them weighing a ton each in the cement, and these are thrown back to support the proof, which never cracks. A post six feet high, with a cap 30 inches long, is set up in each square of 30 feet at the breast, but so far there has been no trouble with the roof.
There is a 10-stamp mill, driven by steam, but it runs only in day-time for lack of water to run longer. The company intend to make a ditch, so that the mill can run day and night. Twenty-five tons of cement are crushed every day, and the average yield so far has been $3 35 to a car load of 1,700 ponnds, or $3 94 per ton. The bed rock, of which 15 inches are dug up, is not crushed, but is simply washed in the sluice.
The stamps weigh 650 pounds each, make 70 to 80 blows per minute, and drop from 9 to 11 inches. When the shoes and dies are new the drop is 9 inches, and the number of blows 80, and when the drop is 11 inches the number of blows is 70.
Three inches of water are turned into each mortar, and three inches more are turned into the sluice below.
The cost of the mill, including the engine, was $12,000, and the expenses daily are the following, viz: a cord of wood, $3; an engineer, $4; a blacksmith, $3; a feeder, $3; six miners, $3 each. Five men breast out five tons per day to a man, and one carman takes out the cement. The engine is of forty-horse power: Two candles are burned per day to the breaster.
The mill was built before the mine was properly opened.
The bed rock does not swell. The bed rock is full of vertical quartz-veins averaging a few inches in thickness, running south-southwest and north-northeast. These seams appear to form in places half of the bed rock; some of them are a foot thick, and some as thin as paper. The same quartz veins, but more strongly marked, are found in a second tunnel, which is 65 feet lower and 350 feet long.
MOUNTAIN GATE.— The Mountain Gate claim, adjoining the Damascus on the west, has 2,000 feet front, and the tunnel runs in 4,000 feet. The bed rock is 35 feet higher than in the Damascus, it swells, there is less quartz in the bed rock, and some of the gravel is softer; but otherwise there is much similarity in the two claims. The tunnel was started 40 feet below the top of the
rim rock, which was passed in 500 feet, and then the tunnel was extended 3,500 feet, running nearly level, and the company are now troubled so much by water that they have started another tunnel 65 feet deeper, and it is in 1,500 feet. The tunnel is about 200 feet from the Damascus line, and they have worked 200 feet on each side of the tunnel. They breast out on the same system as that used in the Damascus.
They have no mill, and when they come to cement too hard to wash, tliey usually leave it behind and virtually throw it away. Some of it, however, is so rich that it pays to crush with a band mortar. The softer cement is washed three or four times, at intervals of six or eight months. Three-fourths of the total yield is obtained at the first washing, and three-fourths of the further yield at the second. The sluice is 200 feet long.
There are 16 partners, all of whom work in the claim, and they seldom Lire anybody. Rumor says the present yield is $12 per day to the man, though the work done is much less than the amount required from hired men. The claim has been worked for 12 years, and has produced altogether $370,000. They have enough water from their own claim to wash all their dirt.
The bed rock rises 150 feet near the western line of the Mountain Gate, and at the eastern line of the Damascus, so those two companies take the whole channel there.
lowa Hill.–At Iowa Hill the blue cement lies on the bed rock, or lay before it was mined out, 12 or 18 feet deep. The cement was so soft that it could be picked out, and so hard that it could be washed once a year for seven years withont being entirely disintegrated. Much of the cement was so rich that it was pounded up in a mortar weighing 250 pounds, and measuring 16 inches across the abowl. The pestle weighed 70 or 80 pounds, was attached to a spring pole, and was worked by two men, who could thus pound up two tons or two tons and a half in a day. Over the blue cement was a layer of sand froin one foot to four feet in thick
Upon that rested a stratum of rich brownish gravel six or eight feet thick. Over this came 140 feet of poor brown gravel, with layers of sand in it, and usually there was a very rich stratum of gravel just over the sand. Above the brown gravel was loam 20 or 30 feet deep.
A few claims on this Blue lead were extremely profitable. The Jamison, the pioneer claim, yielded $500,000; the North Star, $400,000; the Sailor Union, $300,000; the lowa Hill, $250,000; and the Dutch, $250,000; but three dozen large tunnels were run and not one-third of them paid expenses. If the loss were balanced against the profit, the Iowa Hill district would not show much net gain.
The town stands on the summit of a ridge 200 feet high and a furlong wide, and the blue cement of the channel which passes under the town has all been drifted out, and the hydraulic pipe is now at work on both sides, so that the town site will itself be washed away in a few years.
The richest spot ever found in the neighborhood of Iowa Hill was in the brown gravel, from which two men took out $30,000 in one day.
East of Iowa Hill is Indian cañon, reputed to have been the richest cañon ever found in California.
Wisconsin Hill.-Wisconsin Hill is on the same divide with Iowa Hill, but is two miles distant in a southeast direction, and the two places are separated by a ravine. The channel is the same as at lowa Hill, but not so rich.
'The Oriental cement mill at Wisconsin Hill was built in 1866 and has 20 starips, but it does not pay, as the cement yields only 80 cents to the ton. Fortunately, the surface has been stripped, so the cement lies bare and can be obtained at little expense.
Roach Hill.-- Roach Hill, one mile east of Iowa Hill, has had some good claims.
Monona Flat, half a mile east of Roach Hill, has also paid well in places. The channel at these two camps runs with the divide.
Pleasant Flat, a quarter of a mile further up, has a channel running across.
MORNING STAR.—Three hundred yards south of Iowa Hill, beyond Indian cañon, is Picayune divide, through which rnns the Blue lead, on ihich is located the Morning Star claim, which has 1,200 feet front, and extends 4,000 feet to the middle of the ridge. The channel here appears to have been 150 or 200 feet wide. The Morning Star tunnel was commenced in 1856, and no pay of any note was obtained until 1865, by which time a distance of 1,800 feet liad been run and $15,000 had been expended. After reaching the cement it was found that the tunnel was 30 feet too high, and now the dirt has to be hoisted and the water pumped by hand to the level of the tunnel. Tho bed rock swells, and sometimes the track is raised six inches in a night. The cement varies in thickness from six inches to six feet, and yields $3 per ton. The mill has six stamps, goes by steam, and crushes 40 tons in 24 hours. From June to December, there is but half the needed supply of water, and the mill runs only in the day-time. Twenty-four men are employed.
BIRD FLAT AND LEBANON.- Three-quarters of a mile above the Morning Star claim, on the Picayune divide, the Iowa Hill and Bird Flat Company havo been running a tunnel since 1854, have gone in 1,100 feet, have spent $50,000, and have obtained no return as yet.
The Lebanon Company, at Prospect Hill, have a claim which adjoins the Morning Star on the back. They have been at work 13 years, spent $100,000, amil cut a tunnel 1,500 feet, and in 1866 they struck into pay and crectel a 10-stamp mill, which is driven by a hurdy-gurdy wheel. This tunnel is not low enougli.
GOLD RUN.-On the Railroad divide, between Bear river and the North fork of the American, the Blue lead appears at Dutch Flat, Gold Run, and Indiana Hill. The width of the lead here is nearly half a mile, and there are 200 or 300 feet of pay gravel, with no overlying barren stratum. Squires's cañon, which empties into Bear river, separates Dutch Flat from Gold Run. The latter did not obtain a large supply of water until lately, and therefore its best claims have not been exhausted, and it is the most prosperous hydraulic camp in California. Nine thousand inches of water are used here, requiring a payment of $1,000 a day or more in gold. The gravel is peculiarly soft and there is great depth, so that high power is obtained, and more dirt is washed in proportion to the quantity of water used than in any other large hydraulic district.
GRAVEL AT Gold Run.—The bed of auriferous gravel at Gold Run is about 350 feet deep, of which only about 150 feet have been worked so far. The sluices are therefore 200 feet above the bed rock. A shaft was sunk 185 feet deep in Potato ravine to the bed rock, and the bottom of that ravine is below the level of most of the sluices. It is to be presumed that the bed rock in that shaft is no lower than elsewhere in the channel. Pay gravel was found all the way down, and it was soft until within six or eight feet of the bottom. This vast bed of gravel two miles long, half a mile wide, and 250 feet deep, cannot be washed away for many years.
OUTLET.-Although the cañon of the north fork of the American river is at least 2,500 feet deep, yet it is two miles distant from Gold Run, and the tailings must run into Cañon creek, which near the claims is only 150 or 175 feet below their levels. Several claims have been compelled to stop work because they no longer have any ontlet.
An outlet must be obtained 200 feet deeper than Cañon creek, and it must be had without waiting for the gradual washing out of the Blue Lead channel from the cañon of the north fork of the American river. That outlet will be through a tunnel about a mile long, and from this tunnel shafts will run up to the various claims. It will be very costly, but on the other hand it will yield an immense return.