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By C. A. Heberlein

The present war in Europe seems to have stimulated the demand for quicksilver. In July last, the price ranged around $35 per flask of 75 Ib., while to-day it seems to fluctuate between $47.50 and $50. The use of quicksilver in the form of fulminate, containing 70 per cent., and as corrosive sublimate, containing 73.8 per cent., must be extensive and a further market advance may be expected. With such an advance, some revival in quicksilver mining may be looked for, particularly in California, where many abandoned properties exist. What can be done with low-grade quicksilver ores under favorable conditions, particularly with low mining cost, may be seen from the following description of the Oceanic mine, near San Luis Obispo, Cal. Its operations date back to 1876, when rich sand ores were discovered. In three years 7,400 flasks of quicksilver were produced, but since then the deposit has been worked only sporadically . Until two years ago various attempts had been made by the Oceanic Quicksilver Co. to mine the more refractory "mud rock," which was encountered lying beyond the " sand rock." Mud and sand rock in varying quantities were treated together, with poor results, but operations were successful with sand rock of fair percentage. About two years ago, when all the sand rock had been exhausted, Murray Innes purchased the Oceanic mine. He found large quantities of low-grade mud rock, varying from 6 to 8 Ib. of quicksilver per ton, which at the prevailing low price of quicksilver demanded very cheap mining costs, in conjunction with high but cheap metallurgical extraction. At that time the extraction of quicksilver from mud rock ranged between 40 and 50 per cent., as far as I am able to learn. Mining The low cost of mining was the principal consideration, since, with mercury at 50c. per pound, the total gross value of the ore did not exceed

Jan 1, 1915

By G. S. Brooks, L. G. Duncan

During the past few years, the Mineral Point Zinc Co. has had under consideration the improvement of various types of gas-filtering apparatus used in the removal of dust from crushing and milling plants, in the manufacture of oxide, and on blast-furnace fume and sintering furnaces. The original equipment of the various plants of the company was, of course, along lines of the standard stationary bag house. These houses required large surfaces, hand shaking, and varied only in the manner of the collection of solids and in the distribution of the gas. , Early in 1908, the first trial of a mechanical bag house was made at Nassau Plant at Depue, Ill. The duty of this installation was on dust-laden gas from a fine-crushing mill. The Printz and Rau bag machine was finally adopted and put into operation. This ingenious machine embodied what were then to us two novel features in bag-house practice: 1. An intermittent crinkling and snapping of the filtering fabric to free the meshes of solids. 2. A reversal of gas flow for a short period by a temporary connection with the suction trunk. This equipment worked fairly well except in cold weather, when we ran into condensation troubles. Had we at that time understood more fully some of the limitations of fabric filtering work, these might well have been remedied. We were impressed by this experience, however, with the efficiency of sudden tension on the fabric under suction. After a study had been made of some of the western blast-furnace houses using the reversal-of-flow feature, experiments were started early in 3 914 with a view to developing an automatic equipment along the best lines of our past experience. The objects sought were: 1. Keeping labor out of the houses for hygienic reasons. 2. Reduction of labor costs. 3. Reduction in size of bag houses. 4. Accessibility. 5. Ability to handle relatively hot gases where required.

Jan 1, 1918

By Howard Scott

The great advances made in mechanical engineering during recent years through the use of alloy steels, as illustrated by the development of the airplane and automobile, may be ascribed primarily to the application of nickel as an alloying element. The ternary system iron-carbon-nickel has a wide industrial application and forms, further, thefundamental basis of the even greater class of the widely used quarternary steels such as nickel-chromium, nickel-silicon, and nickel-vanadium. As is not uncommon with such cases of virile growth in an industry, the application of the alloy steel in a largely empirical manner has outstripped its scientific development so that a fertile field for metallographic research still remains. In this field, the basic nickel steels require first consideration and are the subject of the present investigation, which is offered as a preliminary to the study of the more complex alloys of industrial importance Of the principal tools of metallography—microscopic examination, determination of mechanical properties, and thermal analysis—the last has developed much more slowly in its application to industrial needs so that the situation often exists that heat treatment operations are based on empirically determined temperatures; that is, temperatures deterrnincd without regard to the actual transformation characteristics of the alloy. This situation is undesirable as there is no uniform standard for comparison of results. It is due, outside the usual difficulties involved in temperature measurements, to the pioneer character of much of the published work; to the lack of definiteness of the Ac, transformation,1 particularly in low-carbon steels; to the failure to define operating conditions completely; and to the paucity of information correlating thermal characteristics with results of heat treatment.

Jan 1, 1922

By Howard Scott

The great advances made in mechanical engineering during recent years through the use of alloy steels, as illustrated by the development of the airplane and automobile, may be ascribed primarily to the application of nickel as an alloying element. The ternary system iron-carbon-nickel has a wide industrial application and forms, further, thefundamental basis of the even greater class of the widely used quarternary steels such as nickel-chromium, nickel-silicon, and nickel-vanadium. As is not uncommon with such cases of virile growth in an industry, the application of the alloy steel in a largely empirical manner has outstripped its scientific development so that a fertile field for metallographic research still remains. In this field, the basic nickel steels require first consideration and are the subject of the present investigation, which is offered as a preliminary to the study of the more complex alloys of industrial importance Of the principal tools of metallography—microscopic examination, determination of mechanical properties, and thermal analysis—the last has developed much more slowly in its application to industrial needs so that the situation often exists that heat treatment operations are based on empirically determined temperatures; that is, temperatures deterrnincd without regard to the actual transformation characteristics of the alloy. This situation is undesirable as there is no uniform standard for comparison of results. It is due, outside the usual difficulties involved in temperature measurements, to the pioneer character of much of the published work; to the lack of definiteness of the Ac, transformation,1 particularly in low-carbon steels; to the failure to define operating conditions completely; and to the paucity of information correlating thermal characteristics with results of heat treatment.

Jan 1, 1922

By Ralph Arnold

While much geological work and drilling have been done in Venezuela, the incompleteness of geological evidence obtainable and the restricted areas in which drilling has been done make any estimates of oil resources extremely speculative. Nevertheless, it is felt that the data given are justified, in the belief that the ideas of a geologist familiar with the region are better than those of a promoter. The oldest beds of interest to oil men are those of the Cretaceous, which are well developed in eastern Venezuela and about parts of Lake Mara-caibo. In both cases, a hard massive limestone is overlain by a great thickness, most of which is shale. In the west, in places this shale is more than 2000 ft. (610 m.) thick, while in the east it-mag attain 3500 ft. (1067 m.). The limestone and parts of the shale are oil producing. In the east, the Tertiary where present is almost entirely covered by the Quarternary, but in the west it is well developed. In probable unconformity over the Cretaceous shales is found a series of sandstones and shales, which may be called the lower coal series. It is well developed southwest of the lake, where it is the oil container, and is probably the lowest series exposed east of the lake. Above this is the Pauji shale, which is probably the point of origin of all the oil east of Lake Maracaibo and in the State of Falcon. It has a thickness of about 3000 ft. (914 m.) in the Mene Grande region. The upper coal series is developed as a great thickness of sands, shales, and clays, with some partly consolidated limestone. Its thickness may be as great as 10,000 ft. It is the oil container of the Falcon-El Mene region and a probable location for oil in some of the area about the lake. It may or may not include the so-called Maracaibo series in which the oil is found at Mene Grande. Over much of Venezuela, the Quarternary is present in unknown thickness, which probably is not great. It obscures oil structure in all cases and presents the greatest hazard of oil exploration for the fields which probably exist below.

Jan 1, 1923

By Henry B. Smith, S. Paul Lindau

ThREe years ago it was decided by the management to granulate the matte that is produced in the smelter of the St. Joseph Lead Co. at Hereulaneum, Mo., thereby doing away with a large amount of labor in handling the matte and in subsequent crushing. On Mar. 1, 1915, the granulator was put in operation and up to Jan. 1, 1916, 18,735 tons had been granulated. The four blast furnaces have a daily output of about 280 tons of pig lead and 100 tons of matte assaying about 11.0 per cent. Pb. It is expected that projected improvements in roasting methods will eliminate more sulphur from the charge, and cut down the matte-fall to about one-half of the present figure. The blast furnaces are tapped into movable forehearths or settlers, 6 ft. by 4 ft. by 22 in., the slag overflowing into 27-cu. ft. slag cars which are hauled to the dump by electric locomotives. Previous to the adoption of granulation, the matte was tapped from the forehearths into small slag pots which were dumped after cooling. The matte cakes were broken with sledges, and transported to the crushing plant for fine crushing and screening. Here the matte was reduced to 1/4-in. size before being fed to the roaster bins. A Wedge and a Holthoff mechanical furnace are used for preroasting before sintering on the Dwight and Lloyd machines. The matte is returned to the furnaces as an iron flux until the gradually accumulating copper content reaches about 7 per cent., after which it is put aside to be concentrated in a small copper blast furnace, the resultant high-grade matte being sold. When the matte does not settle readily from the slag, two settling devices are often used, the second one being a large catch-pot, which gathers any matte that may overflow from the forehearth, the slag then overflowing from the catch-pot into the slag cars. When full of matte, the catch-pot is removed, allowed to cool, and the contents broken and crushed. a With the present plan of granulating, the matte is tapped into 6-cu. ft. iron ladles. These are transported to the granulating plant by a 5-ton

Jan 1, 1917

By Ralph Arnold

While much geological work and drilling have been done in Venezuela, the incompleteness of geological evidence obtainable and the restricted areas in which drilling has been done make any estimates of oil resources extremely speculative. Nevertheless, it is felt that the data given are justified, in the belief that the ideas of a geologist familiar with the region are better than those of a promoter. The oldest beds of interest to oil men are those of the Cretaceous, which are well developed in eastern Venezuela and about parts of Lake Mara-caibo. In both cases, a hard massive limestone is overlain by a great thickness, most of which is shale. In the west, in places this shale is more than 2000 ft. (610 m.) thick, while in the east it-mag attain 3500 ft. (1067 m.). The limestone and parts of the shale are oil producing. In the east, the Tertiary where present is almost entirely covered by the Quarternary, but in the west it is well developed. In probable unconformity over the Cretaceous shales is found a series of sandstones and shales, which may be called the lower coal series. It is well developed southwest of the lake, where it is the oil container, and is probably the lowest series exposed east of the lake. Above this is the Pauji shale, which is probably the point of origin of all the oil east of Lake Maracaibo and in the State of Falcon. It has a thickness of about 3000 ft. (914 m.) in the Mene Grande region. The upper coal series is developed as a great thickness of sands, shales, and clays, with some partly consolidated limestone. Its thickness may be as great as 10,000 ft. It is the oil container of the Falcon-El Mene region and a probable location for oil in some of the area about the lake. It may or may not include the so-called Maracaibo series in which the oil is found at Mene Grande. Over much of Venezuela, the Quarternary is present in unknown thickness, which probably is not great. It obscures oil structure in all cases and presents the greatest hazard of oil exploration for the fields which probably exist below.

Jan 1, 1923

By E. Keller

Some years ago the writer's attention was called to the fact that rolling-mill scales from auriferous copper do not have the gold content proportional to the gold contained in the copper from which they are derived.' So, later, he made a few simple experiments, which are described herewith. In order to test the gold movement on the changing surface of a copper plate under the influence of oxidation, plates 6 in. by 8 in. by 1 in. (15.2 cm. by 20.3 cm. by 2.5 cm.) of converter copper, refined, of 99.29 per cent. purity, and leaded copper with a content of 95.65 per cent, copper, were obtained. Ten cuts were made through the thickness of the plates along the longitudinal center and the silver and gold content ascertained in each of the 10 samples in both plates, as shown in the accompanying illustration. The assay results, recorded in Tables 1 and 2, show that the gold distribution is relatively uniform in both plates, while silver has greater variations, especially in the leaded plate. The plates subjected to oxidation were placed in a red-hot muffle for about 2 hr., two small scarifiers being used as supports. Arranged alongside each other, they nearly filled the width of the muffle, and so were practically under equal conditions of heat and draft. The accurate observance of the time was not possible, however, because of other work, but the time of the exposure of each plate in a pair was identical. At the end of each period, each plate was plunged into water and completely freed of scale, which was carefully collected, dried, weighed, and analyzed. Samples of the plates had also been taken of the molten metal and duly analyzed. Table 3 contains the analytical data for the two plates and their several sheets, or layers, of oxide scales. These figures show that in the oxidations of the converter copper the silver is fairly uniform, while the gold is highly irregular and especially low in the first layer. In the oxidations of the leaded copper plate, the silver and gold contents are variable; however, this irregularity is due to two different causes. The

Jan 1, 1919

By F. C. Newton

RefineRs of lead by the Parkes process have always been solicitous of recovering the zinc used in the desilverization, and justly so, as the loss in zinc constitutes one of the heavy costs in this method of refining. Part of this loss is due to the absorption of zinc by lead, and in the present state of knowledge is not recoverable as metallic zinc. The remainder of the zinc, which finds its way into the precious-metal-bearing crust, is recoverable and naturally engages the operators' most exacting attention. Careful elimination of the impurities in base bullion has enabled the refiner to produce a zinc crust better adapted to retorting, which reflects favorably in the zinc recovery;- and to produce a richer crust, thereby lowering the zineking cost, as the increased efficiency of the zinc results in less of it being in circulation. It is obvious that if the ratio of concentration be increased, a lessening of the amount of crust formed will ensue, throwing less work on the retorts and diminishing the amount of retort metal sent to the cupels, thus making an actual money saving in all these operations. In the effort to obtain a rich crust, the metallurgist has increased the heat to a considerable degree, upon the assumption that at the higher temperature the zinc-dver alloy could be squeezed free from the adhering lead. A further possibility for improvement suggested itself in the freezing-point curve of Prof. H. C. Carpenter, upon zinc and silver. Study of this curve disclosed the existence of a definite chemical compound, Zn3Ag2, with a freezing point of 665" C., a promising compound for practical application. In the experiment undertaken it was endeavored to force this compound into the crust, hoping thereby to obtain a higher concentration than formerly. It was recognized that in bringing a large kettle of lead to such a heat, more fuel would be used, the life of the kettle would perhaps be shorter, and other disadvantages would be experienced. AS a commercial operation, the project would have to stand on its own feet,

Jan 1, 1915

By Howard R. Hughes

In drilling for water and oil to reasonable depths through the generally soft yielding clay and sand formation of the Coastal Plain of Texas, Louisiana, and Mississippi, the rotating method of drilling was adopted, principally on account of the easy and quick penetration, and the low cost of the drilling plant. In favorable ground, free of heavy gravel and rock strata, as much as 1,600 ft. has been drilled in less than 36 hr., although such performances were of course rare. Hydraulic rotary drilling, or, as it is now called, rotary drilling, was used in the above States as early as 1880. The plant consisted of an ordinary derrick, a 25-h.p. boiler, a small hoist, a steam pump, and a water swivel with hose attachment, and an ordinary flat diamond-pointed bit. The successful drilling in of a phenomenal oil well by this process on Spindletop, near Beaumont, Texas, on Jan. 10, 1901, and the ascertained impracticability of drilling subsequent wells in the same locality by other methods (owing principally to heavy quicksand under pressure from below), brought rotary drilling into great prominence, practically to the exclusion of any other process throughout the Coastal Plain, and later on elsewhere. The method, as its name implies, involves the rotation of a pipe by means of machinery placed on the derrick floor. A drill bit attached to the lower end cuts a clearance for the drill pipe, with much the same motion and effect as an auger. Water forced through the drill pipe by means of a pump, and escaping through the bit, removes the cuttings and returns to the surface outside the drill pipe. In this manner the hole is kept open, permitting the drill stem to rotate freely. The pressure of the column of muddy water holds up the walls of the hole until it has been cased. Practically all the wells of the Gulf coast region, numbering nearly 10,000, have been drilled with this system. During the last five years its use has been extended to many other States and countries.

Jan 1, 1915

By Arthur L. Flagg

The Elk City mining district of Idaho occupies a position near the geographical center of Idaho county, a region of moderate elevation in the western foot-hills of the Bitter Root mountains. The district comprises an area of approximately 350 Sq. miles, bounded on the west by the Newsome district and on the south by the Dixie and Oro Grande districts. There are no mining districts to the north or east. Elk City, the principal town and the seat of the mining office for the district, is situated in a hydrographical basin surrounded by low hills. The elevation is 4,200 ft. above sea-level. Through this basin flow Elk Creek, Red river, and American river, which unite west of town to form the south fork of the Clearwater. The one township is set out from the Bitter Root Forest Reserve. Though a railroad starting from the Stites terminus of the Clearwater Short Line of the Northern Pacific railroad has been under consideration for some years, the camp is yet without railroad facilities. The projected road would follow the south fork of the Clearwater on easy grades, but would be very expensive to build and maintain. While such a road would greatly benefit those who are now operating in the camp, and in a sligh degree stimulate interest in its possibilities, there is hardly business enough to warrant its construction. At present all supplies and equipment are hauled in by wagon from Stites, a distance of 58 miles, over a wagon road constructed by the State in 1904, following in the main the old Nez Perce trail. While this is not a bad road, it is not all that might be desired. Starting at Stites at an elevation of 1,327 feet above sea-level, the road runs through low hills to Clearwater, a distance of 10 miles. In the next 16 miles the climb is steady until the Mountain House is reached, which is near the summit of Mount Pisgah. This is the highest point passed on the road, having an elevation of 6,500 ft. From the

Jan 1, 1914

By J. R. Hassemer, T. T. Chao, University of Georgia, K. C. Watts, R. F. Sanzolone

Secondary oxides of Fe-Mn have been used in mineral exploration from the time gossans were first recognized Since gossans are conspicuous features and are largely explored, it is necessary to look for more subtle indication of blind mineralization. Sampling materials used in these geochemical studies consist of secondary Fe-Mn oxide-rich products of hydrothermal mineralization, and "in situ" weathering found in fracture fillings-as selvages along joints and disseminations in host rock. These materials were selectively collected and studied in the Silver City mining region. Two independent sampling methods were compared. The difference in the sampling methods was mainly in the ways samples were obtained and processed. One method involved systematic sampling of fracture fillings and coatings from which secondary Fe and Mn oxides and associated trace elements were then selectively extracted by chemical methods. The second approach involved collection of composite stream sediments and physical extraction of Fe-Mn oxide materials by gold panning, bromoform concentration, and electromagnetic separation. The source of the Fe-Mn-rich materials in the stream sediments is considered to be fracture fillings and coatings that mechanically entered the drainage basins. Map distributions of the two-sample types were compared. Both methods showed generally supportive patterns of anomalous metal dispersion, although anomaly-to-background contrast seems better in joint coatings. Both were useful in distinguishing geochemical differences between mining districts in the region. For example, the Pinos Altos district may contain more hydrothermally-introduced iron than the Central district, whereas the Central district has lead and zinc enrichments that are less on the amount of iron enrichment than is the case in the Pinos Altos district. The methods were qualitatively compared relative to time, expense, and other advantages and disadvantages.

Jan 1, 1984

By A. R. Ledoux

I was wondering whether we were going to adhere to our text. It seems to me that we are having a very remarkable meeting of mining engineers this year, because no matter what the texts may be that are assigned to us, we get back toward something higher; we turn to the consideration of questions of ethics, and of applied Christianity. Yesterday we listened to the most eloquent and remarkable address by Mr. Rickard in memory of Dr. Raymond, and it was told us that he was to speak about Raymond's achievements as an engineer. He did say considerable on that subject, but he was himself carried away with the spirit of the man and moved us all by his portrayal of Dr. Raymond's continued and fruitful labors for the betterment of mankind—that is to say, his religion. Our President asked me if I would say something this afternoon and I find in the bulbtin that the text of the discourses which we are to have here this afternoon is "Internlttional Cooperation in Mining in North America." But again I find that the eloquent speaker who has just preceded me has dwelt largely on ethical and spiritual cooperation rather than upon cooperation in mining. That is, cooperation as men, rather than solely as engineers. The imaginary line dividing Canada from the United States, unmarked by fort or military post, was mentioned by a previous speaker. There are going to be in the future, I am sure, fewer entanglements of the barbed wire of tariff discrimination along our border-—to that end let us cooperate. But there has always been a reciprocity in men. A Canadian conceived and created our great transcontinental line, the Great Northern Railway; an American made the Canadian Pacific what it is. In mining and metallurgy, American engineers, backed by American capital, have built up great Canadian industries while Canadian experts have developed some of the resources on this side of the line. They have done much more than develop our resources; some of them have been our leaders in sympathy for labor. It is therefore not a question of creating a spirit of cooperation, but of giving it freer scope and a fuller realization of fraternity—or, to use the word now more common and of deeper significance—brotherhood. These are days of combination. Corporate interests in this country are now compelled, or at least encouraged, to combine in ways that

Jan 1, 1920

By V.F. Marsters

Peru has produced petroleum since the early seventies, the first work being in the Zorritos field, in the Province of Tumbes, adjoining Ecuador. In the early nineties, the Negritos field, in the Department of Piura, came into prominence, and by 1905 had attained an annual production of 335,160 bbl. The early development of the field was under the general direction of the London & Pacific Petroleum Co., but it is now handled by the International Petroleum Co. In 1900 and 1901, the Lobitos field became the seene of marked activity. In 1905, its total production amounted to 75,000 bbl.; it has continued to increase, as has Negritos. From 1897 to 1902, there was prospecting in the region of La Brieta (or Fernandex), on the Mancora River, about 25 to 30 km. from the coast. Small production of a heavy oil was obtained from three different sands. So far as the author knows, no work has been done in that locality since 1902. There are thus four distinct fields in the north end of the Peruvian coasta1 plain. The remaining productive locality of Peru is the Pirin or Pusi field, at the northwest end of Lake Titicaca, Department of Puno, in southern Peru. The first prospecting near Pusi was done by Brown Brothers, of Los Angeles, Calif., who obtained modest production about 1906; according to reports, activities ceased about 1914 or 1915. The maximum annual production was obtained about 1908, estimated at 76,000 barrels. Peru possesses two distinct geographic provinces in which we may look for the development of a larger oil industry; namely, the coastal plain province, and the inter-Andean plains. Coastal Plain Province The coastal province is most prominently developed in the Province. of Tumbes and the Departments of Piura, and Lambayeque.l It 1 For details concerning the geology of this part of Peru, see Bol. No. 50, Cuerpo de Ingenirros de Minas "Informe preliminar sobre In Zona Petrolifera del Norte del Peru," par V. 1". Marsters.

Jan 1, 1923

By V. F. Marsters

Peru has produced petroleum since the early seventies, the first work being in the Zorritos field, in the Province of Tumbes, adjoining Ecuador. In the early nineties, the Negritos field, in the Department of Piura, came into prominence, and by 1905 had attained an annual production of 335,160 bbl. The early development of the field was under the general direction of the London & Pacific Petroleum Co., but it is now handled by the International Petroleum Co. In 1900 and 1901, the Lobitos field became the seene of marked activity. In 1905, its total production amounted to 75,000 bbl.; it has continued to increase, as has Negritos. From 1897 to 1902, there was prospecting in the region of La Brieta (or Fernandex), on the Mancora River, about 25 to 30 km. from the coast. Small production of a heavy oil was obtained from three different sands. So far as the author knows, no work has been done in that locality since 1902. There are thus four distinct fields in the north end of the Peruvian coasta1 plain. The remaining productive locality of Peru is the Pirin or Pusi field, at the northwest end of Lake Titicaca, Department of Puno, in southern Peru. The first prospecting near Pusi was done by Brown Brothers, of Los Angeles, Calif., who obtained modest production about 1906; according to reports, activities ceased about 1914 or 1915. The maximum annual production was obtained about 1908, estimated at 76,000 barrels. Peru possesses two distinct geographic provinces in which we may look for the development of a larger oil industry; namely, the coastal plain province, and the inter-Andean plains. Coastal Plain Province The coastal province is most prominently developed in the Province. of Tumbes and the Departments of Piura, and Lambayeque.l It 1 For details concerning the geology of this part of Peru, see Bol. No. 50, Cuerpo de Ingenirros de Minas "Informe preliminar sobre In Zona Petrolifera del Norte del Peru," par V. 1". Marsters.

Jan 1, 1923

By George Smith

The Australian Broken Hill Consols mine is situated within a third of a mile eastwards of the famous Broken Rill Proprietory mine; but, so far as has yet been proved, the respective lodes have no connection whatever. The Proprietory line of lode, striking N.E. and S.W., is coincident with the bedding-planes of the inclosing gneiss, and, according to Mr. E. F. Pittman, A.R.S.M., government geologist, is undonbtedly a saddle-formation. This opinion, which met with much opposition at the time it was advanced, is now, I understand, being generally confirmed as the work of development opens out fresh areas for observation along the line of lode. The lode is of immense thickness—in places over 300 feet and though it has been found to contain sufficient quantities of secondary silver compounds to yield phenomenal outputs of silver, its principal constituents are various lead and other ores, and it would appear more correct to regard it as an argentiferous lead-deposit than as a silver-lode proper. The Consols lode differs from its gigantic neighbor in every respect. With an average thickness of not more than 18 inches, it has been worked along its course for upwards of 1300 feet, and at every point yet explored has been found remarkably well-defined and persistent. With a strike E. and W., it cuts obliquely across the bedding of gneiss and schist, continuing uninterruptedly through various bands of eruptive amphibolite. The dip, which is to the south, ranges from 24 near the surface to nearly vertical in the lower levels; but the alteration is not regular, as in places the lode is almost flat, and this at a vertical depth of over 300 feet. These changes of inclination have had no effect on the ore-deposits, which, as I shall endeavor to show, have been governed entirely by " cross-

Jan 1, 1897

By Frederick Görannsen

McDuffie county, once a part of Columbia county, lies in the eastern part of central Georgia, about 20 miles west of the Savannah river, and bounded on the northtwest by Little river. Wrightsboro, now almost forgotten, was one of the principal towns of Georgia before the Revolutionary war, and much of the land hereafter described as belonging to one of the principal gold-bearing sections of the South had been taken up by the early agricultural settlers, and was already under cultivation. Indeed, some of the present mining companies can trace their chain of title back to the original grant of King George III., made in 1771. The first discovery of gold in Georgia, however, was not made until 1823, when two English miners, who had emigrated to this country and were traveling as peddlers through this section, discovered quartz, rich in gold, on what is now known as " the 40-acre lot," and owned by the Columbia Mining Go. These men had no money to buy the lands, and not being able to stake off a claim and begin work, as is the custom in other places, they were forced to seek the aid of the native farmers. In this we are told that they were for a long time unsuccessful; the farmers and land-owners not knowing or caring anything about gold mining. In 1826, Jeremiah Griffin, a wealthy farmer, became interested with them, and they did some prospecting and located several rich veins. Mr. Griffin soon became enthusiastic, and bought about three thousand acres of supposed gold-lands, lying along Little river.. This purchase was unfortunate for the mining industry, as it effectually shut out all other prospectors, and confined entirely to Mr. Griffin and his associates the mining development of the whole region. As a consequence, the ground was never covered, arid there are virgin lands in this section now, which offer to the prospector as

Jan 1, 1903

By Don C. Blackmar

The production of non-ferrous secondary metals has become a large and important industry in the United States, and deals with practically cvery type of manufacturing concern. Its business is unique in that it generally buys frorn its customers as well as sells to them, whether they are individuals, cities, corporations, or the United States government. Its operations are of vital importance to the success and prosperity of nlany of the nation's most important manufacturers; yet there are few industries about which less is generally known by those outside it, whether concerning the rliagnitude of its operations or the details of its actual technique. The industry itself is to blame for this meager publicity, because its technical men have made few attempts to openly exchange ideas, in spite of the excellent examples set by the iron and steel or the copper and brass industries. Whether this is due to the ancient shroud of secrecy generally supposed to cover smelting operations, or because its technical men actually felt that the industry was too puny to be interesting, is hard to say. This paper will consider its subject in a general way, attenlpting to show something of the size and importance of the industry, as well as its fitness to do its work well. Attention will be called to the sound economic reasons for the handling of non-ferrous wastes by specialists, and to the often unseen losses of metals and labor which occur when manufacturc~rs rcclairn thrir own metallic wastes. Magnitude of the Modern Industry No particular thought is given to the kitchen accident whereby a ruined saucepan is sorrowfully tossed into the ash can, yet it is a fairly safe guess that within a month this saucepan, together with hundreds of its follows, will again be in service, perhaps in an autonlobile crankcase, or in an electric vacuum sweeper. It is by this conversion of the useless into the useful, whether from home or large manufacturer, that the secondary tonnage is built up.

By J. M. Gaines, C. H. Herty

IRon oxide (FeO) plays an extremely important part in the manufacture of steel. In the open-hearth furnace and the Bessemer converter it is the chemically predominant compound and controls to a large extent both the operation of the furnaces and the composition and quality of their products. Almost all of the refining action is carried out through the medium of FeO, which oxidizes carbon, manganese, silicon and phosphorus. At the end of any open-hearth or Bessemer heat the steel contains dissolved iron oxide, which must be wholly or partly eliminated. The type of deoxidation product depends on the amount of dissolved iron oxide and on the deoxidizer used. After the heat has been deoxidized and while it is being teemed, iron oxide diffuses from the ladle slag into the metal, causing losses of deoxidizer and increase in iron oxide content of the steel. It is generally believed that non-metallic inclusions are responsible for a great many failures of steel in service and for decreased yield of steel during rolling. The basis of most non-metallic inclusions is dissolved iron oxide. This investigation was undertaken in order to determine the amount of iron oxide that will dissolve in iron under various conditions. Steel-making slags are complex and it has been thought best to determine solubility under simple slags as a first step. The study is being continued under slags whose compositions approach those of operating slags Previous Investigations The solubility of oxygen in iron has been determined by a number of investigators (see Table 1) but their effort's have been directed toward the

By Arthur H. Redfield

In estimating the unmined petroleum reserves of Central America, it is not feasible to employ the methods that have been worked out in thc oil fields of the United States. No producing wells have been brought in and no drilling sections have been made public. It is accordingly necessary to fall back on a crude "barrels per square mile" estimate. The method chosen is a comparison of the structure of the foreign field of unknown reserves with that of some supposedly analogous North American field of which the reserves have been estimated. This method makes no pretense at scientific accuracy, but furnishes a working basis for an estimate. The areal geology of Central America is illustrated in the inap prepared by Sapper and more recently in the geologic map of North America accompanying U. S. Geological Survey Professional Paper No. 71, "Index to the stratigraphy of North America." Disregarding for the present the narrow Quaternary coastal plains and alluvial deposits of the river valleys, three chief zones may be distinguished. These arc: A zone of late eruptive and effusive rocks; a zone of highly folded prr-Cambrian(?) or early Paleozoic crystalline schists and slates, considerably intruded by pre-Tertiary plutonic rocks; and a zone of more or less folded sediments, chiefly of Cretaceous or Tertiary age. The zone of late eruptive and effusive rocks of Central America begins in southeastern Chiapas, Mexico, and extends, with increasing breadth, across southern Guatemala, across practically the whole of El Salvador, and across southern Honduras to the valley of Rio Goascorhn, where the igneous zone attains a width of about 100 mi. (160 km.) East of the Goascordn Valley late eruptives and effusives play a subordinate part, being confined largely to thc Departments of Valle and Choluteca. Dikes and sills of igneous rocks intrude the sedimentary formations of central and northern Honduras. Late igneous rocks cover about four-fifths of the area of Nicaragua. In Costa Rica, late igneous rocks form the diagonal ranges of the Sierra de Guanacaste and the Cordillma Central, and play a part in the upbnild-

Jan 1, 1923