The Dorcas plant output during September was 2,300 tons with a value of $25 for a total of $57,500.

In 1901 the Dorcas Mill handled 21,310 tons at a value of $538,020.

The February production of the Dorcas Mill was 3,000 tons of $24 value for a total of $72,000.

During 1902 the Dorcas Reduction Plant at Florence handled 30,875 tons of ore at a value of $ 846,087.

The application of cyanidation to the treatment of the Cripple Creek milling ores has received a serious check on account of the preference for chlorination, the Dorcas Mill at Florence being the only cyanide mill in continuous operation. This mill has installed what is known as Begeer’s cyanide process.
This process consists essentially in passing the cyanide solution, as it comes from the extractor boxes and after standardizing, repeatedly through a centrifugal pump, which is provided with suitable pipes and cocks to allow the absorption and mixing of air with the solution to the fullest extent, causing the solutions to absorb the maximum of oxygen.

Dorcas Mill.—The plant is running full capacity, and is said to be handling a grade of ore which runs about $200 to the ton, and the mill is credited with making a saving of 98.5% of the assay value of the ore. As is generally known, this mill is situated near Florence.

The January output of the Dorcas mill was 1,500 tons at an average value of $6 for a total of $9,000.

Mr. Edward Walser, of Denver, Colo., has gone to Florence, Colo., where he is in charge of the cyanide department of the Dorcas mill.

Mr. Braden Campbell, formerly in charge of the Dorcas cyanide plant at Florence, Colo., has gone to Mexico to act as assistant to William Farish, of Denver, Colo.

The February output of the Dorcas mill was 2,700 tons at an average value of $45 for a total of $121,500.

The March output of the Dorcas mill was 3,000 tons at an average value of $45.00 for a total of $135,000.

The April output of the Dorcas mill was 2,200 tons at an average value of $70 for a total of $154,000.

The May output of the Dorcas mill was 2,800 tons at an average value of $60 for a total of $168,000.

The June output of the Dorcas mill was 2,800 tons at an average value of $40 for a total of $112,000.

E. Walser, formerly in charge of the cyanide department of the Dorcas mill at Florence, Colorado, has accepted the position of metallurgist with the Montana Zinc Company, Walkerville, Montana.

The September output of the Dorcas mill was 1,900 tons at an average value of $35 for a total of $66,500.

Colorado Springs, Col., Oct. 12.—The September output of district production was impacted by unknown amount by the shutting down part of the month of the Dorcas mill at Florence owing to the necessity for repairs in the machinery, as was also the case in the Sioux Falls plant in this district.

The October output of the Dorcas mill was 3,500 tons at an average value of $35 for a total of $122,500.

During October the Dorcas plant processed 3,500 tons with an average value of $35 and a bullion value of $122,500.

During January the Dorcas plant processed 3,400 tons with an average value of $32 and a bullion value of $108,800.

SLIMES TREATMENT.
In reducing ore to the required fineness, an appreciable amount of fines are always made. In dry crushing some of these fines are lost as dust. There is, however, at present in well-governed mills little or no loss during the crushing of the ore, as efficient dust collectors are on the market, which not only collect the dust made by the rolls, screens, etc., but will deliver the same, continuously and in a manner suitable for the work. The initial efforts were to reincorporate this with the coarser sands, but such practice has not been all that could be desired, and at present this part of the ore receives special treatment.

The filter-press treatment is considered both burdensome and expensive, and has not found much favor in this country. A modification of the filter-press method, making use also of decantation, has been in use for the past year at the plant of the Dorcas Reduction Company, at Florence, Col., and is described by the management as follows.
Four large 70-ton agitation tanks, 13 feet 6 inches by 20 feet high with conical bottoms, are used. Into one of these tanks from 10 to 12 tons of dust are charged, solution sufficient to make a thin fluid is added, and then the whole mass is agitated with compressed air from the lower part of the bottom until the extraction is complete.
The air simply is then discontinued and the charge allowed to settle for some time. The liquor is then decanted off through a vacuum pan 20 feet by 5 feet 6 inches high, the same pan being subsequently used for washing and finally for draining the slimes. The washing is extended only to a point necessary to maintain the volume of solution. The cyanide losses are given as being about 2 pounds per ton of dry slimes treated and the extraction as 93.50 per cent.
This treatment is made on the dust without roasting, the dust coming from the telluride ores of Cripple Creek district. The total time of treatment is stated to be five days over all.

These operations are worthy of special notice for the reason that, a hitherto considered stable compound (telluride of gold) toward cyanide solutions is brought within the field of commercial possibilities. The method is said to be simple and effectual.

TREATMENT OF HIGH-GRADE ORES.
The cyanide process has been regarded as appropriate for the treatment of low-grade ores only. This conception has come from the early use of the process, the original application being made to tailings. This would intimate a limitation as to value of ore which could be economically treated.
Simple logic, together with acquaintance with a few facts, should be all required to clear this question. Thus, if all the gold contained in a unit weight of ore was in one particle, then it would follow that the size of this particle would increase with increasing values of the ore, but this is not true— commercially, at least. We are, therefore, licensed by nature to assume that with increasing values an increasing number of particles ensue. This premise is enforced by fine crushing.
Now if it takes T time to dissolve one particle of gold in position P in the ore, other things being equal, it would require no greater time to dissolve another particle in position P2. In fact, this would be true if the number were extended to Pn —where n is less than infinity.
This is not intended to moan that coarse gold is not present in ores of higher values— this may or may not be true, since coarse values are peculiar more to types of ore rather than to grade. We see, therefore, that there is no a priori reason why ores of any value should not be successfully treated by the cyanide process where the ores are amenable to any chemical process.
Let us now look to general practice.

The Dorcas Reduction Works is a custom mill, treating Cripple Creek ore, which is purchased upon full assay value and paid for. It is then crushed, roasted and cyanided. The average value of the ore treated during the past three years is given me by the management as being $35.00 per ton, and frequently for months as high as $60.00, the highest average for a single month being $86.02. These values are above the average treated by other chemical mills working on the same ores.
The average extraction for the greater values is given as being from 95.00 to 96.50 per cent, while for the lower grades assaying approximately $25.00 per ton it is between 93.50 and 94.50 per cent, which means that the unavailable gold in the higher grade ore is not greater, practically, than in the lower grade, and confirms the above conclusions.
This plant treats normally 125 tons per 24 hours, and has been in operation for some four years.

The Dorcas Mill treated during June 3,300 tons with an average value of $32.50 for a total of $107,250.

Denver, Sept. 29—The reason of the refusal of Stratton's Independence Co. to renew contracts with the American Smelting & Refining Co., and with the Mill trust, is explained by the purchase of the Dorcas cyanide plant, at Florence, which has been successfully operated for several years, for a sum in the neighborhood of $200,000.
As about 5,000 tons of ore are shipped by the lessees every month, undoubtedly a large part of this will be treated at Florence from now on.
The company has been considering the erection of a plant of its own for some time past.

Denver, Colorado.—The refusal of the Stratton's Independence company (limited) to renew ore treatment contracts with either the mill or smelter trust is explained in the purchase of the Dorcas mill at Florence for a sum said to exceed $200,000.
The various lessees on the company's property at Victor are shipping a total of 5,000 tons of ore per month, more than enough to keep the Florence plant busy.

Denver, Nov. 8—The Cripple Creek statement that the Dorcas mill at Florence, which is the most successful cyanide plant in Colorado, has been purchased by Stratton's Independence Co., was premature, as the deal has not been consummated yet.
The purchase of the Dorcas cyanide plant at Florence by Stratton's Independence Co. has not yet been made, but the deal is pending. The company is considering the adoption of the Cassell process for handling part of their ores.
A. Chester Beatty having resigned as consulting engineer, George E. Schroeder was appointed in his place.

Denver, Colorado.—Charles M. Becker, general manager of Stratton's Independence mine, has returned from London, where he spent two months with the officers of the Venture corporation, owners of the mine. Among subjects under consideration by officials is the adoption of the Cassell process for handling dumps and low grade ore of the mine, and the purchase of the Dorcas mill at Florence for handling ore of average grade.
Mr. Becker states he is in communication with the New York and London office with regard to the probable purchase of the Dorcas, but that the deal is not assured. The Cassell process was investigated by the directors, and while it gained favorable consideration, it has not so far been adopted.
George E. Schroeder, of California, has been selected as successor to A. Chester Beatty, who recently resigned as consulting engineer.

Dorcas Mill.—This plant, located at Florence, was entirely destroyed by fire on the 19th inst. The loss is about $300,000, partially covered by insurance amounting to about $200,000.
The plant was constructed in 1900 and treated about 150 tons of ore per day by the cyanide process.

Denver, Colo.—The Dorcas smelter at Florence was destroyed by fire recently. No announcement has been made as to the plans of the company.

Dorcas Mill.—It is announced that this plant, which was recently destroyed by fire, is to be rebuilt on a larger scale.

The Dorcas mill, at Florence, was destroyed by fire early in the year of 1906.

The large chlorination and cyanide mill of the Dorcas Mining, Milling, and Developing Company, at Florence, was destroyed by fire in March, 1906.
This was a custom mill, treating Cripple Creek ores.

Cyaniding Cripple Creek Ores
In the Journal of Dec. 2, 1911, credit is given to Philip Argall for the solution of the problem of treating low-grade Cripple Creek ores. Permit me to point out that as early as 1900 I strongly advocated treating these ores by cyaniding and that the real pioneer was the late Mr. Howard, at whose Dorcas mill, in Canon City, Colo., these ores were treated as early as 1901 on a commercial basis by cyaniding.
R. W. Hadden. Los Angeles, Calif., Dec. 12, 1911.