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By F. R. Koeberlin

ABOUT thirty miles south of the port of Coquimbo, Chile, nestling in one of the western outliers of the main Andes range, lies the little mining town of Andacollo, a place whose history and traditions make up one of the most romantic pages in the life story of this southern republic. The beginning of Andacollo is shrouded in the penumbra of the pre-Columbian era, but its first mining activity probably dates from about the years 1440 to 1460. It was in the middle of the fifteenth century that the Inca Tupac-Yupanqui, grandfather of Atahualpa, conquered this part of Chile. His domain extended even as far south as the present site of Santiago, and perhaps farther, but was maintained with increasing difficulty against the fiercely independent and indomitable tribes of Araucanian Indians of the South.

Jan 1, 1938

By Ernest F. Burchard

MOST of the iron ore smelted in Alabama blast furnaces is mined within Alabama, although deposits in the neighboring States of Georgia and Tennessee may be drawn upon when occasion requires. Of the four commercial kinds of iron ore, the anhydrous ferric oxide, hematite (Fe2O3) ; the hydrous ferric oxide, mostly the type commonly known as limonite (2 Fe2O33H2O) ; the carbonate, siderite (FeCO3) ; and the magnetic oxide, magnetite (Fe:3O4) ; the first two are found in abundance in Alabama, the third in less than commercial quantities, and the fourth only rarely. Both the hematite and the hydroxide are found in somewhat different forms according to their geologic environment. The Red Mountain hematite, of Silurian age, that crops out in well¬defined beds for 1.50 miles northeast-southwest and 40 miles northwest-southeast is the predominant source of ore. Only a small part of this area carries ore of commercial value; Birmingham and Gadsden are now the only centers of production. The ore is of sedimentary origin, probably altered from vast deposits of greensand mixed with calcareous, fossiliferous. marine debris. Other types of hematite not vet mined commercially are in metamorphosed rocks-red ore in slates in Columbiana Mountain and specular hematite (gray ore) in quartzite in the Talladega Hills.

Jan 1, 1938

By AIME AIME

EITHER the 2300 people who came to the Annual Meeting were in a better frame of mind or they were resigned to their fate, or it was a better meeting than usual. Whatever the reason, at the 1nstitute?s 148th meeting the attendance was better than ever before, things went more smoothly than in some previous years, and complaints appear to have been almost entirely absent. Patience was sometimes reauired but. almost without exception, it was forthcorning the well-known recession seems to have given many members enough leisure time to come to the meeting without depriving them of the tangible wherewithal to come.

Jan 1, 1938

By Oliver Bowles

AUTOMOTIVE TRANSPORT by highway, which has become indispensable to modern life either in peace or war, involves the use of powerful machines, many of which travel at high speed. To start, accelerate, and stop each motor vehicle demands the use of clutch and brake. Friction is applied intensively to both these mechanisms, and their linings must therefore be of materials that will resist wear and that will not ignite with the heat of friction. Asbestos, that curious fire-resisting: natural fiber that may be woven into unburnable cloth, is eminently suitable for this special' use, and no satisfactory substitute for it has yet been found Because- asbestos is regarded as absolutely essential to all types of motor transport on land, and in addition is indispensable to. many .other kinds of machines and equipment, the situation of the- United State's with respect to supplies of-raw-material-is of special interest: From the standpoint of national self-sufficiency, conditions are far, from satisfactory, for United States mines furnish only three to four percent of the total domestic require-

Jan 1, 1938

The Bureau of Mines is operated to assist in promoting economic development through increased efficiency in the mining, preparation, treatment, and utilization of mineral substances; to aid in conserving mineral resources through preventing waste; and to help the mining industry improve health conditions and increase safety. Accomplishment of those ends is sought through investigation of scientific, technologic, and economic problems of the, mineral industries and dissemination of resulting information. Building materials of mineral origin constitute an important product of mining, and the Bureau makes studies of these in the various fields mentioned. The following commodities come within this classification: Asbestos, anhydrite, asphalt, cement, clay and clay products, diatomite, dolomite, glass and mineral wool, granite, greenstone, gypsum, lightweight building materials, lime, limestone, magnesite, marble, sand, sand and gravel, sandstone, sand-lime brick, slate, soapstone, and trap rock.

Jan 1, 1937

By George S. Rice

A novel method of extinguishing a mine fire in a stowed or gob-filled area by employing liquid carbon dioxide under high pressure eras used recently with success at the President (Prasident) coal mine, Bochum, Germany, as reported by P. Cabolet in Gluckauf (Apr. 24, 1937, p. 393) The use of carbon dioxide gas as a fire-fighting agent in surface plants and in ships is now general practice in the United. States, but when it has been tried for extinguishing fires in mines in large areas more or less confined by stoppings it has not been successful. Examples of the latter method of attempting to fight mine fires are given in Bureau of Mines Bulletin 229, Fifty-Nine Coal-Mine Fires; How They Were Fought and That They Teach, by G. S. Rice, J. VT. Paul, and 14. VT. von Bernewitz (1927). The reason for its nonsuccess may be either that the stoppings are not tight or that the roof and pillars are more or less fissured and enough air passes into the area to sustain a slow fire, whether of spontaneous origin or produced by gas explosion or other source of ignition.

Jan 1, 1937

By S. R. Zimmerley

[In the course of a flotation investi~ntion, a siliceous gold ore was ground ir, R 'ball mill to ~inils 300-mesh. It mas found that the small mount of zlus 300-~esh mnterial had a go12 assw approximately twice that of the oricinal ors, md thst this oversize ~roduct also contained much abra?.ed iron. >!oreover, the gold assay of the abraded iron, which was separated ma~etic-dl:;, wno ei::ht tiaes tkat of the ore. These facts sug,~estsd th~t sone r3laticnshin existed between the abnormally high .gold content and the preseace of abrade4 iron. It was ciecided, therefore, to investl~ate furtkor ths acsoclation of the ;old nith the iron abraded from the balls durir-g grincing. As a nrelininary ex?rr>hent, a samy?le of siliceous gold ore 786 grolznd for 1-1/2 hours i;l 3 ball mill and the nuln was divided into two products electri~mag-etically. The racult s follow: ]

Jan 1, 1937

By J. A. Allan

OCCURRENCES of salt in Alberta have been mentioned and described by the writer in 1929 (l) and by Cole in 1930 (2). Brine springs occur at a number of places along the valley of Athabaska river north of latitude 56 degrees, and also on the south margin of Salt prairie, twenty-five miles west of Fitzgerald in the vicinity of the 60th parallel of latitude, which is the boundary between Alberta and the Northwest Territories. These salt springs were visited by Sir James Richardson in 1820, and in the same year D. W. Harmon stated that " ... clown Salt river there are several places where almost any quantity of excellent dean white salt may be taken with as much ease as sand along the seashore" (3). One hundred years later, in 1920, when the writer first visited these springs, the "dean white salt" which had accumulated about the springs was about 400 tons ( 4). This paper deals with a thick deposit of rock-salt which has been proved by drilling in the vicinity of McMurray. Particular attention will be given to a well drilled at Waterways early in 1936 by Industrial Minerals, Limited, when a continuous bed of rock-salt was penetrated with a thickness of 199 feet. As this paper is being presented, a salt plant is being completed and a production well is being drilled at the plant. < is salt deposit is in the vicinity of McMurray, close to the junction of the Clearwater and Athabaska rivets, in township 89, range 9, west of the 4th meridian. McMurray is about 240 miles northeast from Edmonton. As shown on Figure 1, Clearwater river, which rises at Methy portage, in Saskatchewan, enters Athabaska river at McMurray. Some three miles above the mouth of Clearwater river, the Hangingstone enters from the southwest. Waterways, where the latest salt development has taken place, is situated at the end of the Northern Alberta railway, a distance of 304 miles from Edmonton. This railway reaches the bottom of the Clearwater valley at Draper station, about 3 miles east of Waterways and near the mouth of Deep creek. The Draper bituminous sand plant is approximately half a mile east of Draper station. About one mile south of the townsite of McMurray, Horse river enters the Athabaska from the east.

Jan 1, 1937

By M. W. Von Bernewitz

The Bureau of Mines receives frequent requests for information on the treatment of mercury ores, but as its own and almost all other publications on mercury are out of print, the Bureau has prepared this circular on the metal for the prospector and operator of small mines and plants. Mercury, commonly though improperly termed ?quicksilver?, is the only common metal that is liquid at ordinary temperatures. Mercury is used in the amalgamation of gold and silver, in power boilers, explosives, friction-less bearings, laboratory apparatus, lamps, medicine, paint, rectifiers, and for ?silvering.? The last mentioned is being superseded by silvering with silver. The use of mercury boilers may increase when they are thoroughly understood, but amalgamation is -being replaced to some extent by the use of corduroy and other collecting mediums, such as jigs and flotation cells.

Jan 1, 1937

By Jos. R. Guiteras

This paper describes the operations of the St. Joe Mining & Milling Co. in Boulder County, Colo., as of June 1936. Later a brief visit was made to the mine in September 1936; information obtained at that time has also been recorded. The company operates a gold mine, the Grand Republic, in the Sugar Loaf mining district; a 100-ton flotation mill in Lefthand Canyon near Gold Hill; and a custom sampling punt, the Boulder Ore Sampling Works, at Boulder, Colo.

Jan 1, 1937

By Paris V. Brough

This paper, which describes the practice of milling custom ore, in addition to that produced under company and lease operations in the Tom Reed mines, is one of a series &apos;being prepared by the Bureau of Mines. ACKNOWLEDGMENT Acknowledgment is made to W. B. Phelps, managing director, and Jack Zwinge, superintendent, far permission to publish, a-ad to G. E. Jarpe, the present mill superintendent, for his assistance in preparing the paper. LOCATION The mill is in Oatman, adjacent to the Benjamin Harrison shaft of the Tom Reed Gold Mines Co., in the foothills on the western slope of the Black Mountains, western Mohave County. The railroad shipping point is Kingman, Ariz., 25 miles northeast of Oatman. Paved highway U. S. 66 passes by the mill. The altitude is approximately 2,700 feet.

Jan 1, 1937

By S. R. Zimmerley

[In the course of a flotation investi£ation, a siliceous gold ore was ground in a&apos;ball mill to &apos;:1inns 300-meeh. It wa. found that the small amotIDt of _Ius 300-mesh material had a gole.. assay approximately twice that of the oriGinal ore, &~d that this overs.ize nroduct also contained much abrac..ed iron. .,Joreove I the gold assay of the abraded iron t which was !1epnrated ma§metically&apos;, ~iVFl.£ eight ti;nes that of the are. These facts suggested that some r31aticnship ex?...,ted between the abnorma11y high gold content an the prese:1ce of brA-cit)" iron. It was decided, therefore, to investigate furt~er th~ Fl.Gsociation of the bold ~ith the iron abraded from the balls during sri~Qing ]

Jan 1, 1937

The D&apos;Arcy Exploration Company Ltd. has been granted prospecting licenses in Great Britain to explore four different types of prospect. In the south of England (Dorset, Hampshire and Sussex) the objective lies in Jurassic and Lower Cretaceous beds. In an area of approximately 4470 sq. miles, covering parts of Nottinghamshire, Lincolnshire and Yorkshire, the search is directed to testing Carboniferous rocks. In northeastern Yorkshire a single license covers structures in which the Permian limestone will be explored. In Scotland, southeast of Edinburgh, the company holds another single license where Lower Carboniferous horizons are the objective. Southern England Among the more important "indications" that led D&apos;Arcy Explora-tion Company Ltd. to undertake a testing program in southern England was the discovery of sands in the Wealden (Lower Cretaceous) series of Dorset, impregnated with oil residues. Traces of oil and bitumen were also found in limestones of the Portland and Purbeck beds of the same area. In addition, traces of petroleum had been recorded from Upper and Lower Jurassic beds in borings, more especially those drilled in the course of coal exploration in Kent and Sussex, and an outcropping oil sand was known to occur in Wealden beds near Pevensey in Sussex. Besides these tangible proofs that at least some oil has been generated in this area, _the Jurassic beds, as developed at outcrop in Dorset and elsewhere, include considerable thicknesses of strata that may well be considered as possible source rocks of petroleum. A regional view suggested that these possible source rocks extended, without great thinning, beneath at least the southerly parts of the Weald of Sussex, the South Downs and still farther south beneath the English Channel. It appeared, and still appears, a reasonable conclusion that, where suitable structural conditions occur in this tract of country, an oil accumulation of commercial value may be found. Of the several possible anticlinal structures, those at Portsdown (Hampshire) and between Henfield and Steyning (Sussex) were selected as sites for the first test wells. The groups of strata which at outcrop sug-

Jan 1, 1937

By C. E. Julihn

In the fall of 1933 a new discovery of gold was made in the old Mojave mining district of California about 70 miles north of Los Angeles. It led to mining operations that have surpassed in their results all reasonable expectations and are of exceptional promise for the future. In less than 3 years, exploration has opened up a number of veins, from some of which a substantial amount of high-grade ore has been shipped, while a large tonnage of milling ore has been disclosed. Two mills, operating on ore averaging better than $12 a ton, will probably produce more than a million dollars worth of gold in 1936, and a considerable increase of their output in the following year is anticipated. While continuance of these operations for a number of years is already assured by ample reserves of ore, future discoveries of still other veins are reasonably possible, as occurrence of gold throughout the volcanic rocks of the district is widespread and the veins now being mined showed little to attract attention at the surface.

Jan 1, 1937

By H. P. Allen

THE Achotla mill of the Cia. Minera de Pe[n]oles is of special interest in that it is one of the few still employing the chloridization process. The ore milled comes from the Suriana mine and consists of both oxide and sulphide, from neither of which can the gold or silver be extracted by a simple cyanide treatment. The mill was built in 1927, after several years of study in the development of the process1, and operated from December of that year until October 1930. Operations were resumed in February 1935, and have been continuous since, treating approximately 5000 tons per month, while the mine is getting up to full tonnage of 6500 tons per month. Transportation Of Supplies The property is in Guerrero, Mexico, some 175 km. by airline southwest of Mexico City. The mill site is at Temisco (Fig. I), 8 km. from the Balsas River and 4.8 km. by aerial tram from the mine. At Temisco are the general office, shops, warehouses and laboratory serving both mine and mill. Here sufficient water is available either from a small creek running through the property or from the Balsas River, also convenient and ample storage space for the tailings. With the exception of the mine timber and a few native building materials which may be obtained locally, all supplies for both mine and mill are brought down the Balsas River from Balsas, the terminal of a Mexican National Railway line out of Mexico City. The method of transportation on the river is interesting. Rapids with very fast water are numerous, prohibiting the use of mechanically propelled boats. Those used resemble large, flat-bottomed rowboats some 22 ft. long by 8 ft. wide (Fig. 2). They are manned by two oarsmen sitting in the bow, each handling one large oar, and usually another man in the stern who, with his oar, assists in steering the boat, especially when the rapids are run. From 3 to 7 tons of freight are carried on each boat, depending upon the stage of the water, which governs also the time

Jan 1, 1937

By R. S. Dean

The work of the metallurgical fundamentals section during the past year, representing active experimental investigation or thermodynamic study, may be summarized as the following problem subjects: 1. Low-temperature specific-heat investigations. 2. Development of a method of concentrating gases. 3. Thermodynamic properties of metallic carbides and nitrides, 4. Production of pure chromium from chromium chlorides. 5. Thermodynamic properties of the hydrates of calcium, sulphate. While this list is not identical, with officially designated problems, due to overlapping of subjects and to new developments within specified problems, presentation upon the basis of this subdivision will best serve to review the work of the section.

Jan 1, 1937

By H. P. Greenwald

[In many coal-mining countries, during he pest decade, there have seen made extended studies and accurate measurement of movement of roof strata, tests of the physical properties of specimens cut therefrom, and tests of the strength of end load on artificial supports. Naturally, such studies have been more extensive in European countries, where mining conditions are less favorable than in the United States. As a part of its work in the conservation of coal resource and prevention of accidants in mines, the Bureau of brines began systematic measurements of the movement of roof strata to in coal mines in the fall of 1935. It was decided- that, in the beginning, work on a rapidly retreating rib line in a mechanized mine would give the greatest amount of information in a reasonable time. To this end w cooperative tine agreement was made with the Pittsburgh Coal Co., through Dr. L. E. Young, vice: president in charge of operations, for conduct of work in that company&apos;s Montour 10 mine operating in the Pittsburgh coal bed. This paper gives an account of the methods used in the investigation, excerpts from the data obtained, and such generalizations as appear to be justified.]

Jan 1, 1937

By G. E. Murray

Lead blast-furnace work at Trail is unique in that this is the only plant in the world where blast-furnace smelting on a large scale for both lead and zinc recovery is carried on under one management. On this account the factors that determine economic practice differ from those of other lead smelters. In addition to this different metallurgical outlook, a great deal of structural investigation has been carried on, which has resulted in the development of a furnace which should prove of interest to all who are faced with similar problems. This description may be conveniently divided into various heads as follows: (1) General—make-up of charge, etc.; (2) structural—(a) hoods and charging methods, (b) shaft construction, (c) crucible construction; (3) handling slag; (4) handling bullion; (5) metallurgy. The Charge The Trail plant is an old one, on a congested site. As with most old plants, this limits the method of charge preparation. In general, lead metallurgists will agree that sinter when it reaches the blast furnace should contain as small an amount as possible of actual fines. There would be some difference of opinion as to the maximum size as well as of the minimum required, but to obtain the optimum condition some form of screening is indicated. This screening should take place immediately before the blast furnace if possible, and because sinter deteriorates in storage there should be as little as possible. There should also be the minimum amount of handling between the sinter machines and the furnaces. Unfortunately, at Trail the sinter must be handled considerably before it is charged to the furnace, and no feasible scheme of screening has yet been devised. Trail practice, then, demands that the sinter be a strong one physically. Dependent upon the amount of lead in it, it has been found advantageous to incorporate granulated slag into the final sinter, the amount varying inversely as the lead content. The addition of this slag makes a harder sinter, which arrives at the blast furnace in a better condition, but it entails some lack of efficiency, because desulphuriza-tion is not so rapid nor so complete.

Jan 1, 1937

By F. H. Edmunds

I N presenting this paper, the writer wishes to point out some of the difficulties and problems of geological work in that part of Saskatchewan in which outcrops are few. These problems are well known to all geologists who have made investigations in this region, but may not be so well known to those outside. A table of the strata as known in certain areas of Saskatchewan and the adjacent provinces is given, with a brief discussion of some of the formations and beds about which there is little knowledge due to their being deeply buried and not exposed in the region. Comment with regard to possible oil and gas structures is made and some features of the structures in the Battleford and Simpson districts are described. The writer wishes to make acknowledgment to members of the Geological Survey of Canada to whose work in Saskatchewan and the adjacent provinces reference is made, and to others who have made, or are making, valuable contributions to the stratigraphy of Saskatchewan. Mr. G. C. Webb has kindly furnished information regarding and materials taken from a well bored recently in the Paynton district. Special thanks are due to the Simpson Oil and Gas Company for permission to use much valuable information with regard to their wells and for the generous way in which the officials and staff co-operated with the writer. The opportunities the writer has had to visit many parts of the Province have been in connection with investigations for the Provincial Department of Natural Resources and through facilities provided by the Department of Soils of the University of Saskatchewan. To these Departments the writer accords his thanks. For the purposes of this discussion, Central Saskatchewan may be considered as that portion of the Province extending from Township 16, with Regina, Moose Jaw, and Swift Current situated on or near the southern boundary, to Township 48, with Prince Albert and Lloydminster on the northern boundary. This region includes territory underlain by Cretaceous sediments and excludes the southern portion of the Province, where Tertiary beds underlie the surface and are exposed to an extent sufficient to permit a measure of systematic mapping.

Jan 1, 1937

By Oliver C. Ralston

Nonmetallic technologic investigations of the U. S. Bureau of Mines are headquartered at experiment stations in three widely separated localities of the United States. During 1936, the Nonmetals Division of the Technologic Branch was formally set up by combining the direction off the work of these three experiment stations under one administration. The New Brunswick (N.J.) station which in the past has been known as the Nonmetallic Minerals Experiment Station, is henceforth to be at College Park, Md., as part of the Eastern Experiment Station, and its principal activities will be related to the nonmetallic resources of the Eastern and New England States.

Jan 1, 1937