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By G. M. Brownell

Introduction The Flin Flon mine is located on the boundary line between the provinces of Manitoba and Saskatchewan at a point about four hundred miles northwest of Winnipeg. A branch of the Canadian National railway provides the town of Flin Flon with direct transportation facilities. The property was staked in 1914 and, after a considerable amount of exploration; the Hudson Bay Mining & Smelting Company was organized and brought the property into production in November, 1930 (1). Mining is carried on by open pit and underground methods at the rate of about 4,400 tons per day. Production for the year 1934 was: 99,334 ounces of gold; 1,335,319 ounces of silver; 37,486,054~pounds of copper; and 49,427,280 pounds of zinc; in addition to small amounts of cadmium and selenium. The Flin Flon deposit is one of the largest low-grade ore deposits in Canada with complete hydro-electric and metallurgical plants for the production of blister copper and electrolytic zinc. Previous Work The development of the Flin Flon mine into one of the major mining operations in Canada has created a need for a more detailed geological study of the area. Practically all of the information published to date concerns the general surface features. It is the purpose of this paper to deal more specifically with the ore-body and its relationship to the enclosing rock as revealed by studies made possible through recent underground development. The earliest published report on the area is by E. L. Bruce (2), who made a reconnaissance geological investigation of the region for the Geo-logical Survey of Canada in 1914 and established the main. petrological units. Several years later the area immediately around Flm Flon was mapped in greater detail by F. J. Alcock (3). In the summer of 1934, the area of Missi sediments to the north and east of the mine was studied by J. W. Ambrose. His report has not yet appeared in print but his findings are of importance.

Jan 1, 1935

By R. S. Dean

MANY studies have been made of the properties of steel produced by adding varying amounts of sponge iron to the charges used in steel-making furnaces.1-3 The results of these previous studies, however, have failed to disclose a reason for the belief of steelmakers that steel made in this way is definitely different from steel made entirely from scrap or iron melting stock. This paper deals chiefly with the structure of the sponge iron, of the wrought iron made by welding the sponge iron into blooms, and of the steel made by melting the forged and rolled blooms. It is believed that the structure of the final steel is inherited from the ore and that this inherited structure produces marked differences in the properties of the steel and explains the feeling of steelmakers which is based on their experience. Three kinds of sponge iron were used in this investigation: One made from a limonite ore reduced with natural gas, one made from a hematite ore reduced with natural gas, and one made from a magnetite ore reduced with charcoal. The sponge iron made by reduction with natural gas

Jan 1, 1935

By Benjamin Webber

MANY of the auriferous placers of the arid Southwest differ widely from the standard types of stream and eluvial deposits of more humid regions, although exhibiting some of the features of each. This diver-gence in characteristics is of geological and economic importance and appears sufficient to warrant the consideration of these placers as a class distinct from both stream and eluvial deposits. It is hoped that the consideration of these auriferous gravels as a distinct type of deposit will facilitate recognition of morphological and economic features that might remain obscure if these deposits were viewed in the light of stream or eluvial placers whose type locality is a more humid environment. "Bajada placer" is proposed as the designation for this type of placer deposit. Bajada is the Spanish term for slope and is used locally in the Southwest to indicate the lower slope of a mountain range, the portion consisting of rock debris and standing at a much lower angle than the rock slope of the range proper. It has been used in a geologic sense by Schrader1 and others. The type locality of bajada placers is the Sonoran Desert,2 where they occur on the bajada or rock debris slope of desert ranges. Stream placers are represented in the Southwest, but most of them lie within the mountain topographic province, the Mexican Highlands2 section of, the Basin and Range physiographic province. Eluvial placers may occur in the mountainous semiarid Mexican Highlands but are almost unknown in the extremely arid Sonoran Desert, as mountain slopes are generally too steep to permit the accumulation of any considerable mantle of residual debris. Since their salient distinctions are almost wholly the result of formation under conditions of extreme aridity, bajada placers are largely confined to the Sonoran Desert, although a few occur in the adjacent Mexican High-lands. They may be modified by the action of ephemeral streams, in which case the placer gravels of these arroyas approach stream placers in type and habit of occurrence, but their relation to an arid environment and the bajada type is usually apparent.

Jan 1, 1935

By H. S. Martin

The Phosphate Recovery Corporation operates three flotation plants, Nos. 1 and 2 concentrators about three miles northeast of Mulberry, Florida, and No. 3 plant at Wales, Tennessee. These plants represent the first commercial phosphate flotation operation and are also believed to be the largest nonmetallic flotation operation in the world at the present time. The details of this paper will be confined to plant No. 2, this being the newest and largest concentrator in Florida, and the flow sheet being practically the same as at plant No. 1. The No. 3 plant has been operated but a short time and has been shut down since December, 1932, on account of the decrease in phosphate rock production. The phosphate washers usually are located centrally on a known deposit so that about two hundred acres of ground can be mined economically to each washer location. The washers are moved to new areas when the distance becomes too great for economical pumping. The flotation plants are built either adjacent to a washer, so that current debris may be utilized, or on the site of a former washer where there is sufficient accumulated debris available for mining, and the flotation plants must also be moved from time to time. Most of the water used in the Florida flotation plants is recovered after passing through a circulating system where most of the fine suspended matter is settled out, but some make-up water is obtained from deep wells near the plant. Power is obtained from the Tampa Electric Co. through the distribution facilities of the International Agricultural Corporation. Flotation concentrate is hauled from the plant by trolley over the International Agricultural Corporation's trolley system, to the drying plant at Prairie, one mile northwest of Mulberry. Ore Treated In the pebble phosphate district of Florida, the phosphate mineral, or collophane, is usually found in horizontal beds of varying thickness

Jan 1, 1935

By G. C. Gester

With the exception of exploration geological work that is being prosecuted in various parts of the mainland of Arabia, the only new developments in Arabia during 1934 were on Bahrein Island, which is in the southwestern portion of the Persian Gulf, approximately 25 miles from the mainland of Arabia. Here the Standard Oil Co. of California, through its wholly owned subsidiary, The Bahrein Petroleum Co., Limited, has continued to carry on a systematic drilling campaign and has constructed camps, pipe line and marine loading facilities. During 1934 eight wells have been completed at depths ranging from 2058 to 2253 ft. These wells have shown average initial productions ranging from 1500 to 5000 bbl., with one, No. 15, estimated as being capable of flowing as much as 11,000 bbl. per day. The oil is asphaltic in character and has a gravity range of from 32' to 34' A.P.I. The locating of all new wells has followed a plan of orderly development, with the ultimate object of obtaining efficiency of operation and maximum production. The wells are taking a penetration of 200 to 250 ft. of the lower or so-called Main productive zone. The upper oil zone, which is cased off, includes 300 to 400 ft. of alternating limestones, clays and shales and carries a heavier oil under lower pressures. The Main zone is similar lithologically to the upper zone. Micro-fauna collected from cores have shown that the oil occurs in formations of lower Eocene and Cretaceous age. Development to date has not progressed sufficiently so that either the maximum thickness of the oil-bearing horizons or the limits of the field can be determined. Something over 10,000 acres has been proven to date. Among other developments leading toward the marketing of oil from Bahrein during 1934 was the construction of a marine loading terminal. This included the laying of over 3 miles of 12-in. submarine pipe line from the small island of Sitra out into the harbor, terminating in 50 ft. of water; also the laying of more than 10 miles of gathering lines from the producing area to the terminal. Three crude oil working tanks with floating roofs were erected on Sitra Island, having a capacity of 250,000 bbl. A pumping plant was provided having a capacity of 5700 bbl. of oil per hour. This is housed in a dustproof building, as rather severe

Jan 1, 1935

By Alden B. Greninger

THE time-honored description of the growth of metal crystals to form polycrystalline aggregates is. one in which two important steps are considered: (1) nucleation, and (2) dendritic growth, each dendrite starting from its individual nucleus and resulting (upon slow cooling, assuming no solid phase changes) in a macrograin. This picture of the process of crystallization is incomplete, and it is with the hope of enlarging upon it that the following summary and correlation of experimental results are given. MOSAIC STRUCTURE For an exact definition of the mosaic structure of metal crystals-if, indeed, one can be found that will hold for all metals-one must await the results of much experimental work in this field. The writer's investigations have been. confined almost entirely to copper and a few of its alloys. The following terms are proposed, and will be used in this report: Macromosaic Structure1.-Large-scale mosaic structure; more specifically, mosaic structure of a scale large enough to produce splitting of Laue spots on back-reflection Lane X-ray patterns2. The deviation from exact parallelism of neighboring macromosaics varies from a few

Jan 1, 1935

By J. L. Rodda, R. L. Wilcox, E. C. Truesdale

IN recent years various problems in connection with research work on the preparation and properties of zinc-base alloys have required reliable information concerning the constitution of the zinc-rich portion of the iron-zinc equilibrium diagram. On numerous occasions rather positive indications were obtained that, for example, the solubility of iron in zinc was incorrectly represented on .the current equilibrium diagrams.. A careful study of all the available literature relating to the iron-zinc system led to the conclusion that much of the early work was unsatisfactory as measured by present standards of experimental accuracy, and as a result it was decided to redetermine the location of the liquidus curve and of adjacent portions of the diagram. Part I. of this paper comprises a description of the experimental methods and a summary of the results by means of which the zinc-rich end of the iron-zinc diagram has been revised in the following ways: 1. Measurements of the solubility of iron in liquid zinc by several different sampling methods, leading to a relocation of the liquidus curve. 2. Microscopic, conductivity, and X-ray studies of the solid solubility of iron in zinc, which, together with thermal analyses, have resulted in new values for the solid solubility and the eutectic temperature and composition. 3. Heating and cooling curves, obtained by a refined differential method, leading to new locations for the two peritectic horizontals. In Part II of the paper the attempt is made to review all of the published work having a bearing on the constitution of the iron-zinc system, and to correlate the present results, and some recently published data

Jan 1, 1935

By G. D. Tranter

THE importance of ladle and teeming practice and its relationship to the yield and quality of the product has focused considerable attention on this phase of open-hearth operation. Inherently bad steel cannot be perfected by manipulation during teeming, but through the proper handling of "off heats" serious losses, which in many cases arise, can be greatly minimized. Conversely, good steel can be ruined as a result of poor workmanship in the pit, and rendered unsuitable for application to orders where exacting surface and physical requirements are essential. Sufficient evidence has been secured to warrant careful investigation of pit operations when an abnormal number of basic defects develop in the semifinished product or are found on the inspection table. This paper is written from the standpoint of the problems involved in making satisfactory ingots for sheet rolling. Furthermore, since rimming steel is almost universally used for manufacture of sheet, the data presented herein refer particularly to that type of steel. Going back some 30 years in open-hearth history, the word "pit" properly described the hole into which the ladle was lowered to receive the metal tapped from the furnace. The working space was necessarily limited, and the disposal of slag and metal overflowing the ladle or lost because of breakouts presented a serious problem. The equipment, of course, was rather crude in the light of present-day development. Often no ladle stands were provided, the ladle being hung on the crane beneath the runner. When delayed taps occurred, the ladle was often held in position for many hours, thus tying tip pit operations and causing delays to adjacent furnaces. Because of crowded conditions, slag thimbles were not used and a network of cast-steel triangles and old tapping bars, placed before the heat was tapped, was the means for removing slag from the hole. Furnaces of different capacities were used

Jan 1, 1935

By T. D. Yensen, N. A. Ziegler

AGING is a term that connotes a slow change in properties under ordinary operating conditions. It can be accelerated by increasing the temperature and by mechanical straining. The magnetic properties of iron and some of its alloys have for many years been known to be subject to such a change. But the cause of the change was not recognized until a few years ago after mechanical age-hardening in nonferrous alloys of the "duralumin" type had been definitely shown, by means of solid solubility curves, changes in electrical resistance and microanalysis, to be caused by slow precipitation of one or more constituents from the solid solution. The similarity between the solid solubility curves of such alloys (Fig. 1) and those for iron-nitrogen (Fig. 2) and iron-carbon alloys (Fig. 3) below the Al transformation point suggested at once that magnetic aging of iron might be caused by a similar process; namely, by the slow precipitation of carbon and nitrogen in the form of Fe4N and Fe3C at ordinary temperatures because of a cooling rate that had been too rapid to permit complete precipitation according to equilibrium conditions. This suggestion has since been amply confirmed, particularly by the comprehensive work of Köster1 on the effect of nitrogen and carbon. Typical curves are shown in Fig. 4 for the relationship between aging temperature and coercive force. Previous to the establishment of the precipitation-hardening theory it was thought that the effect of nonmetallic elements like C, N, 0, etc., on the magnetic properties of iron was greatest when these elements were retained in solid solution, atomically dispersed throughout the interstitial spaces of the iron lattice2.

Jan 1, 1935

By C. Norman Bowers, Blaine B. Wescott

MARKED improvement in the serviceability of sucker rods has been effected in the last two years, partly because of the insistent necessity for greater economy in the operating costs of crude oil production growing out of the general industrial depression and partly because many of the recently developed fields have imposed more severe operating conditions upon both surface and underground equipment. The latter is particularly true of Kansas, where practically all of the oil produced. is associated with damaging amounts of hydrogen sulfide brine and where the method of establishing potential production demands equipment capable of being operated at maximum capacity without interruptions. The decline of flush production in the Oklahoma City field created new problems in deep-well pumping on a scale heretofore unequaled and the increased proportion of water it has been necessary to produce in the fields of the Greater Seminole area presented conditions that were acutely in need of betterment. The problem in the latter fields was complicated by the shift towards sulfide characteristics, which accompanied water encroachment, and it is probably true that nowhere, at the present time, are pump¬ing conditions generally as severe as in this territory. The Mid-Continent district, therefore, has become the proving ground for the numerous materials that have been proposed for sucker-rod fabrication. The information that ultimately will be obtained from an unprecedented amount of field experimentation will pay ample dividends when the decline of East Texas increases the demand for the vast reserves of sour crude in West Texas. It is a rare occurrence in industry that the use of such a simple piece of equipment as a sucker rod presents so complicated a problem for solution. As proof of this, it is only necessary to consider the numerous types of sucker rods on .the market at the present time and contrast this condition with that of less than four years ago, when it was the common aim of manufacturers to develop a single sucker rod for all conditions of

Jan 1, 1935

Jan 1, 1935

By E. H. Henderson

MR. R. V. NEILY stated that he had at one time operated at Goldenville. The practice and results are much the same now as in the olden days. Inside plates were then found to be a source of trouble and had been removed. At the Libbey mine, Queen's county, the sulphides carried considerable gold, and $45.00 to $60.00 per ton had been recovered from the concentrates by roasting and chlorinating. Later, concentrates were treated with bromocyanide. Following that practice, a cyanide leaching plant was installed, which did not require concentration of the tailings. Cyanidation brought a recovery of around 95 per cent, with but $300 worth of plant. In Nova Scotia, the ore of each locality presents an individual problem of its own as to treatment required. Ma. W. B. Timm stated that, in the majority of Nova Scotia gold ores, more than 75 per cent of the gold content is free-milling and, naturally, stamps are most efficient for collecting and amalgamating this gold. In Ontario and the West, they had got away from stamps, and perhaps the main reason was that the supply of battery-men, who came from Nova Scotia, had died off. Ball-mills had been installed, which required smaller space and handled large tonnage, even though, as far as amalgamation goes, the stamps were probably more efficient. If concentration is to be done, ore from stamps is usually in better shape for recovery in passing over the tables, as there is no slime. With the ball-mill, flotation is necessary. The better practice, undoubtedly, is to take out what gold is possible before it is all smashed up, as in the ball-mill, though recent developments in the ball-mill make it possible to trap and take coarse gold directly from the mill. In this way, cyanidation is speeded-up, due to saving of the time the coarse gold would take before going into solution. PROFESSOR A. E. FLYNN found it unusual in these days to read anything in favour of the stamp mill, and thanked Mr. Henderson for the excellent paper in which he upholds the stamps and backs his opinion with facts from actual operations. For the typical Nova Scotia ore, containing coarse gold, stamps are un¬excelled. It used to be said that the virtue of stamps is that they brighten the gold for amalgamation. Although this saying is almost classical, it is not true, for gold is never brighter than in the native, untouched state. Any hammering that gold gets makes it more difficult to amalgamate.

Jan 1, 1935

By F. Bahnemann

IN discussing the problem of abnormal magnetic polarization, C. A. Heiland1? emphasized the unfortunate fact that our knowledge of the geological and physical conditions relating to such occurrences is very limited and that a more detailed insight into their physical causes would be extremely valuable for interpreting measured anomalies. He also pointed out that to arrive at quantitative physical formulas that would express the conditions that cause abnormal polarization many more occurrences of the kind would have to be recorded. The first part of this paper is a contribution to such descriptions.

Jan 1, 1935

By W. A. Schaeffer, Sidney A. Justin, Jr. H. D. Easton

Restriction and proration of petroleum production have increased materially the difficulties attendant upon the estimation of reserves, particularly in large, "flush" fields. Such practices preclude the use of decline or other curves, from which, under capacity production conditions formerly prevalent, much could be learned as to the ultimate recovery to be expected from a given field or lcase therein. In restricted fields that would produce at many times the low rate allowed by the regulations in force if allowed to flow without restraint, one is forced to use other information than production performance to predict the volume of oil recoverable. Examples are: at Kettleman Hills, California; the Conroc, Van and East Texas fields, Texas; the Iowa field, Louisiana. It is beyond the scope of this paper to apply a definite method to the determination of the reserves in any actual field, therefore the discussion will be limited to a consideration of available methods and an enumeration of important factors governing the accuracy of such estimates. The problem is to determine not only oil in place but recoverable oil in place, for a given field or tract, which is complex and depends not only on the characteristics of the reservoir but also on the plan of development, the production allocation scheme, the rate of production and many other factors. Many data must necessarily be considered, weighed as to inportance, and assigned quantitative values. Estimates of recovery in prorated fields have been discussed by Brace', Shaw2, Snider3 and others. The wide difference in estimates of ultimate recovery from a number of important recently developed fields demonstrates the inadequacy of

Jan 1, 1935

By Joseph E. Pogue

The petroleum industry has been involved in Lore collective planning than any other American industry, with the exception of the railroads and utilities, and therefore is of interest as a case study in the experimental attempts to regulate the economic consequences of free competition. Planning is of course an integral part of effective management, hence at the outset a distinction must be clearly drawn between competitive planning and collective planning. By competitive planning is meant the aggregate of plans drawn up and prosecuted by the competing units occupying a field of enterprise; by collective planning is meant a collusion of plans, either originating among some or all competitors, or else imposed upon them, whether accepted or resisted, by some superior authority, usually the state. The prevailing popular concept of "planning" as applied to industry appears to be a program of conduct superimposed upon an industry unwilling or incapable of achieving a socially and economically desirable result under free competition. In this brief and tentative analysis of the subject, competitive planning is left to one side and attention is focussed upon the matter of collective planning as defined above. A basic functional difference between the two categories of planning is that in the case of competitive planning the individual plans are small, numerous, and tend to offset one another when in error; whereas in the case of collective planning, the separate plans are larger in scope, fewer in number, and tend to escape the incidence of the principle of compensation. In viewing the evolution of collective planning in the petroleum industry we find that during the past 20 years there have developed four more or less well defined collective plans and that at the present time the industry is deeply involved in a collective planning trend pointing toward further varieties. The four plans, which are to some degree transitional, may be conveniently named from the chief incidents that led to their formulations. The first collective plan was the program of control developed during the World War and hence called the war plan. The second plan was one originating within the industry in the period between the war and the inflation of the late twenties and called the inventory

Jan 1, 1935

By Alden B. Greninger

Many recent contributions in the field of theoretical metallography have been concerned with crystallographic definitions or descriptions of various phenomena. The lattice orientation of the crystal being studied must be known before such definitions can be made. Practically all the metallic crystals used do not have crystal faces—other than the unknown "plane of polish"; hence resort must be had to other means of determining orientations. Some use has been made of etch-figures, slip bands, optical properties, etc., for this purpose; but for accurate results, and because of the fewer restrictions to their use, the various X-ray methods have been the most satisfactory.' The methods that have been used may be divided into two general classes: (1) oscillation methods, and (2) transmission Laue methods.² The disadvantages of these methods are numerous, chief among them being the time required to determine a complete orientation. No method proposed so far is wholly satisfactory for determining the orientation of a small macrograin within a polycrystalline aggregate.

Jan 1, 1935

By G. R. Hopkins

The average quantity of heat needed to refine a barrel of crude oil in 1934 was 638,000 B.t.u., or about as much heat energy as contained in 5 gallons of fuel oil. Although the total heat utilized in 1934 was slightly above 1933, crude runs to stills increased 4 percent, hence the average requirement per barrel declined from 660,000 B.t.u. in 1933 to 638,000 B.t.u. in 1934 (see fig. 1). The average for 1934 constitutes a new record for firing efficiency, being just under the previous low of 1929. Heat consumption at refineries depends on many factors, of which the trends in yields of gasoline and lubricating oils are probably most important. The yield of gasoline is indicative of activity at cracking plants, which type of plant utilizes more than the average amount of heat per gallon of product. The yield of lubricating oils is indicative of the extent to which credo oil is refined; that is, it takes considerably more heat to refine a barrel of crude through lubricating oils than it does to separate only gasoline and kerosene. The yield of gasoline decreased from 43.7 percent in 1933 to 43.4 percent in 1934; on the other hand, the yield of gas oil and fuel oil increased. Although the yield of lubricating oils increased slightly in 1934 the theoretical increase in fuel requirements probably was offset by technical improvements, such as solvent refining.

Jan 1, 1935

By W. A. Binsacca

The concentrator treats sulfide ore containing lead, copper, zinc, gold and silver, at the rate of 850 tons per 24 hr., and produces lead, copper, zinc and iron concentrates by selective flotation methods. The ore occurs below the oxidized zone along a main fracture, the wall rock of which is either greywacke or calcareous shale. The predominating sulfide minerals are galena, sphalerite, pyrite and chalcopyrite; the others are quartz and calcite. In minor amounts, arsenopyrite, pyrrhotite and hematite occur, and such secondary minerals as smithsonite, chalcocite, covellite, bornite, cerussite and anglesite are detected in the ore, the last two named occurring principally as surface alterations of the galena. The ore is hauled from the mine bins in 10-ton cars which pass over the track scales before entering the car dumper ahead of the crusher plant.' A conveyor belt delivers the crushed ore to the sulfide bin, which has a capacity of 2800 tons. The primary grinding unit consists of two 6 by 12-ft. Marcy rod mills operating in parallel and in open circuit, each taking 425 tons per day. One rod mill discharges into an 8 by 25-ft. Dorr classifier with a 12-ft. bowl and the other into a 6 by 25-ft. Dorr duplex classifier. These classifiers are arranged so that each unit rakes the sands into a 6 by 14-ft. Traylor ball mill, which discharges to the bowl classifier only. The duplex classifier therefore operates in open circuit and the bowl classifier in closed circuit, the overflow of both classifiers furnishing the feed for the flotation section. Other groupings have been tried, but this has been found the most satisfactory. The Marcy mills are driven by 150-hp. slip-ring induction motors with speed reducers to give 17 r.p.m. The Traylor mill operates at a speed of 24 r.p.m. and is driven by a 200-hp. slip-ring induction motor, direct connected to pinion and gear. The bowl classifier operates at a speed of 22 r.p.m., with the bowl rake making 4.5 r.p.m. and the duplex classifier at 31 r.p.m. High-carbon steel rods of Mexican manufacture, 12 ft. long by 3-in. diameter, are used in the Marcy mills, with a resulting consumption of 1.52 Ib. per ton ore. The Traylor mill is fed 3-in. cast-iron balls cast in

Jan 1, 1935

By W. M. Small

Austria.—Austria produced some 430 cisterns of 10,000 kg. each of crude oil of a 0.9428 sp. gr. during 1934. Gosting II well near Zis-tersdorf was placed on the pump in August and at the end of the year was still producing about three cisterns daily. This well is owned by the Erdöl-Produktionsgesellschaft while Gösting I is owned by Raky-Danubia. Only five wells were completed in the republic during the year. These accounted for 1783.5 meters of the 2225 meters drilled. The only producer completed was Gosting 11. At the close of the year, four rigs were in operation and one rigging up. At least 8 or 10 new wells are planned in Lower Austria for 1935. The European Gas & Electric Co. put its 6-km. gas line into operation in May and has sold 12,301,550 cu. m. of gas to the Vienna City Electric Works. A 2-km. pipe line was built from Gösting II to the railway loading rack near Zistersdorf. Hungary.—No oil or gas was produced except a small amount of gas trapped from flowing artesian wells. The Government completed and abandoned a 1500-m. hole at Tisztaberek in northeastern Hungary and is drilling at 967 m. near Bogáes, 120 km. northeast of Budapest. It is unofficially reported it plans to drill two new wells in 1935. The European Gas & Electric Co. has a rig up for a test at Mihalyi in Transdanubia. Czechoslovakia.—In Gbely (Egbell) there were produced 1283 cisterns of 10,000 kg. of 0.935 sp. gr. oil and a small amount of gas used for fuel. This field is operated by the Government; 17 shallow producing wells and three dry holes were drilled, with a total of 3351 m. of hole completed. In Hodonin (Goding) there were produced approximately 1300 cisterns of 10,000 kg. each of 0.91 sp. gr. oil and a small amount of gas used for fuel. The field is operated by the Apollo, which drilled four producing wells averaging 460 m. in depth, one small gas well of 550 m., one small gas well 260, and one dry hole 230 m. Two wells were deepened a total of 80 meters. The Government is drilling below 800 m. in a wildcat test in eastern Czechoslovakia near the Rumanian frontier.

Jan 1, 1935

By C. V. Brennan

This paper, describing the various mining methods and practices at Britannia mines, Britannia Beach, British Columbia, is one of a series covering mining practices, methods, and costs in the mining districts of the United States and Canada. The Britannia property has been operated continuously for 30 years, and in that time many diverse methods have been used in exploiting the various types of orebodies worked. Under normal conditions mining methods include surface gloryholes, shrinkage stoping, shrinkage with powder drifts for primary breaking, horizontal cut-and-fill, horizontal and inclined square-setting, and timbered and open rills, the three latter systems being combined with close filling. The Britannia method of mining, a large-scale retreating shrinkage system usually combined with powder drifts for primary breaking, has been developed and applied here very successfully. Each block of ground as developed is studied as a separate problem, and the mining method, or combination of methods best adapted to the work in hand is applied thereto. Operating at, capacity, the series of mines produces 7,000 tons of ore per day.

Jan 1, 1935