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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 E. L. Estabrook

Oil companies operating in foreign countries have made increased use during 1930 of cooperative agreements in prospecting unproven territory and in developing proven territory. A considerable proportion of the existing foreign fields are held under single ownership and have been developed as units. The operating companies seek to maintain this condition by acquiring land in large blocks or by merging smaller concessions under unit operating agreements. Your committee has secured a number of reports on foreign non-competitive operations and a valuable formal paper which deals with the Golden Lane of Mexico.l 0. B. Knight has drawn some valuable comparisons concerning costs of development and ultimate production between a certain competitive area and another noncompetitive area along that strip of rich producing territory. After discussing details of production, numbers of wells and cost of drilling and production, he concludes that the 93,700,000 bbl. of competitive oil will have cost $0.193 per barrel as compared to 85,700,000 bbl. of noncompetitive oil at $0.059 per barrel. The saving of $0.134 per barrel amounts in round figures to $11,500,000, which is 21/2 times the total cost of developing the non-competitive block. The cost for drilling and development of the two areas of 3550 acres which Mr. Knight compares was $18,150,000 under competitive and $4,760,000 under noncompetitive conditions. The estimated ultimate production of the competitive 3550 acres is expected to reach 93,700,000 bbl., or 8,000,000 bbl. above the noncompetitive block. Under ordinary production methods it is to be expected that a noncompetitive area will yield less oil per unit area than will a similar competitive area, because of closer spacing and more rapid extraction in the latter case. The advantage of noncompetitive conditions, in this regard, is that the undivided ownership makes it possible to apply repressuring as a production method fairly early in the life of the field and thus, in the end, to vastly increase the yield. In the particular region described by Mr. Knight, repressuring is not thought to be a factor of

Jan 1, 1931

By Ming-Kao Yen

S. E. MADDIGAN*—I think Mr. Yen should be complimented on doing a very excellent and a very comprehensive piece of work. I was particularly pleased to note the use of X rays in a somewhat less tedious technique than pole figures. In the past I think many workers have been diverted away from the use of X rays in such investigations because of the large amount of work involved in pole figures if one is dealing with a great number of specimens. The same thing, I think, applies to the determination of orientations by counting of twins which is also a very tedious procedure; as a result several papers which have otherwise been of excellent quality have depended upon etching techniques for determination of orientation. The present paper indicates that the results reported in those previous papers were correct, but I think the use of etching techniques alone is a rather shaky basis for setting up theories in the literature. W. M. BALDWIN, JR.*—This discussion will be a short note of correction and apology. In my discussion of Brick, Martin and Angier's paper I incorrectly reported the orientation of phosphorus deoxidized copper annealed at temperatures. When I learned that Mr. Yen was preparing the present paper I asked that he correct this previous error, which he most graciously consented to do. However, through my ambiguity the correction noted on p. 59 of Mr. Yen's paper is still not the proper one. For this I take full responsibility. The orientation which I observed in phosphorus deoxidized copper at high temperatures is the (112) [111] which agrees with the pole figure given in Fig 8a, on p. 65 of Mr. Yen's paper. Our observations were made on the basis of twin counts rather than X ray determinations and therefore serve as an independent confirmation of Mr. Yen's data. M. K. YEN (author's reply)—The author wishes to thank Dr. Maddigan for his comments in regard to the application of glancing technique to textures. As a matter of fact, considerable work has been done recently in connection with

Jan 1, 1950

By E. Gaujot

IN connection with the question of coal waste and economy in mining, we would call the attention of those interested to an apparatus invented by M. Dernencourt, Superintendent of the Anzin Division of the Anzin Coal Company, North of France. This apparatus is known in France and Belgium under the name of prop screw-jack (vis botte), and has been used with good results in the above-named countries for some years past. M. Ponson gives, in his " Trait6 de I'exploitation des Mines," a description of it (page 533), but as the description given is old, the work not widely known in this country, and as some valuable improvements have been made since, I thought it might be useful to give a description of it, having seen it in 'operation in 1867, while in Europe to attend the great Exposition, and on a scientific tour to the mining districts of France, Germany, Belgium, and Italy. The prop screw-jack is composed of the following pieces : I. The body or column B, Fig. 4 [Plate (I)], of oak or yellow pine, sawed square, the bark taken off, and any length, proportionate to the vein. The smallest are 10 inches diameter at the base, and 9 inches at the top, the height being from 12 to 15 inches less than the size of the vein. In the axis of this column, and at the top end, is a cylindrical opening or hole, C, 22 inches diameter, 10 inches deep, for the screw, S. II. Two wrought-iron rings, R R, to strengthen the two extremities of the column ; the rings must be put on hot. III. A cast,-iron washer, E, with hole in centre a little larger than the screw, to be put on the top of the column, and on which the nut is to rest; the top side of this washer must be faced on the lathe, also the bottom of the nut, to prevent friction. IV. The screw, S, having a total length of 12 inches and a diameter of 24 inches (for very high veins this diameter may be increased to 3 inches), and has on its top a wrought-iron plate, T,

By Arthur F. Wendt

Within the last few years the production of iron, and of the metals generally, by a given furnace-plant, has been largely increased, in many instances trebled. Iron-furnaces exceeding one hundred tons' capacity per diem are now the rule in new constructions. Copper and lead-furnaces smelting from 60 to 100 tons of ore per day are common. With this greatly augmented product, the life of furnace-linings has been diminished, and recourse has been had to various cooling devices for prolonging the life of such liuings. The object of this paper is to call the attention of the profession to an arrangement recently patented by the writer. The common course of projecting water against the exterior of the brickwork of a furnace has been in a large measure abandoned by our most progressive managers. All have recognized the danger of this proceeding, especially when applied to the crucible of a furnace below the line of the tuyeres. Cast-iron water-jackets, with wroughtiron pipes for circulating the cooling-water, have replaced the cruder methods. In iron-smelting the use of such jackets has been confined to the crucible and the space around the tuyeres; and it has been the custom to support the jackets on the brickwork of the furnace. But the erosion of the brickwork below tuyere-jackets allows them to sag, and often displaces the alignment of the tuyeres and leads to other annoyances. The principle of construction adopted by the writer to remedy this and other evils, is to use a thin fire-brick lining (not over nine inches) from the tuyeres up to the bosh, to back this lining with wrought-iron or steel water-jackets, hung from the mantel-ring, and thus to carry the whole weight of the furnace and its filling upon the supporting pillars. The crucible proper is lined with three or four thicknesses of fire-brick on the sides, and not less than forty-eight inches in the bottom. It is supported on independent pillars, and is practically an independent structure. It could even be placed on wheels and made removable, were there any adequate advantage to be gained by such an arrangement.

Jan 1, 1885

By J. F. Wolff

The iron formation of the Gogebic Range in northeastern Wisconsin and the northwestern part of the Upper Peninsula of Michigan, resembles that of the Mesabi Range in Minnesota very closely in lithologic character and the subdivisions and horizons that can be recognized. It contains numerous interbedded slaty layers and considerable intraformational conglomerate in certain horizons. In contrast to the flat dip of the Mesabi formation, the Gogebic dips steeply to the northwest at an average angle of about 70". It has a quartzite and siliceous slate foot wall and a hanging wall of conglomerate, graywacke and slate. The black and gray Tyler slate has been designated the hanging wall of the Gogebic iron formation in U. S. Geologicial Survey monographs, but between the true Tyler slate and the commercially important Gogebic iron formation, and apparently unconformably upon the latter, is a series 600 ft. or more thick of conglomerate, slate, graywacke, and cherty iron formation, the latter being of no commercial importance on the Gogebic Range as far as now known. This series is probably that described as the "Capps" on the eastern Gogebic by the Michigan Geological Survey. The Gogebic iron formation proper can be subdivided into three main horizons, a lower cherty and an upper cherty with a banded or slaty horizon between them, corresponding to the three lower horizons of the Mesabi. Several minor subdivisions can be made of these major ones. Orebodies occur in all three horizons of the Gogebic series and in some places ore is developed across practically the entire series. Dikes and Sills The Gogebic iron formation has been intruded most intricately by basic dikes and sills, most of the former pitching east but some pitching west. One very extensive sill is intruded near the base of the lower slaty or banded horizon, in the formation known locally as the Yale slates. One extensive bedding or strike fault is associated with this sill and a great many transverse faults occur at different places along the Range. The combination, or association, of steep dip, faults, dikes and sills has produced conditions very favorable for the development of orebodies through the leaching, oxidation, and consequent concentration effected

Jan 1, 1925

The stabilization of a gravel road with soil is a method of treatment developed in recent years by the United States Bureau of Public Roads for the purpose of binding the constituents together better, and maintaining a more durable surface. The process consists in adding to the gravel or crushed stone and sand, a soil mortar, so-called, of fine sand, silt and clay, mixed in the proper proportions. The coarse gravel and sand supply structural strength and hardness; the fine sand adds embedment support to the coarse sand; the silt acts as a filler to prevent the granular particles from rocking; while the clay serves not only as a binder but also provides pores minute enough to cause connecting moisture films which are supposed to have high cohesive properties'. It will be recognized that the clay is an important ingredient both when wet and dry, and should not show excessive expansion when wet, nor correspondingly high shrinkage in drying, as otherwise there is danger of unseating the nonplastie particles. Such a stabilized road, although an improvement on one with a floating surface, will in course of time be subject to wear, and become dusty when the clay dries out and breaks up. It has been found that if some salts are added to the road mixture they tend to maintain the soil moisture and prevent dustiness of the road or raveling of the road surface. In addition to this, it is claimed that these dissolved salts cause a thinning of the moisture films on the particles, thus permitting greater compaction of the road mixture, and thereby increasing its density. This fact can be proved by noting the increased compaction which a road mixture shows when certain salts are added to the soil water. Since certain chemical substances such as sodium chloride are electrolytes, the question arises whether they cannot have wine effect on the qualities of the clay in the soil mortar, and perhaps improve them. In view of the fact that certain salts seem to exert a favorable effeet on the road mixture it is desirable that they he held in the road soil as long a time as possible.

Jan 1, 1938

The stabilization of a gravel road with soil is a method of treatment developed in recent years by the United States Bureau of Public Roads for the purpose of binding the constituents together better, and maintaining a more durable surface. The process consists in adding to the gravel or crushed stone and sand, a soil mortar, so-called, of fine sand, silt and clay, mixed in the proper proportions. The coarse gravel and sand supply structural strength and hardness; the fine sand adds embedment support to the coarse sand; the silt acts as a filler to prevent the granular particles from rocking; while the clay serves not only as a binder but also provides pores minute enough to cause connecting moisture films which are supposed to have high cohesive properties'. It will be recognized that the clay is an important ingredient both when wet and dry, and should not show excessive expansion when wet, nor correspondingly high shrinkage in drying, as otherwise there is danger of unseating the nonplastie particles. Such a stabilized road, although an improvement on one with a floating surface, will in course of time be subject to wear, and become dusty when the clay dries out and breaks up. It has been found that if some salts are added to the road mixture they tend to maintain the soil moisture and prevent dustiness of the road or raveling of the road surface. In addition to this, it is claimed that these dissolved salts cause a thinning of the moisture films on the particles, thus permitting greater compaction of the road mixture, and thereby increasing its density. This fact can be proved by noting the increased compaction which a road mixture shows when certain salts are added to the soil water. Since certain chemical substances such as sodium chloride are electrolytes, the question arises whether they cannot have wine effect on the qualities of the clay in the soil mortar, and perhaps improve them. In view of the fact that certain salts seem to exert a favorable effeet on the road mixture it is desirable that they he held in the road soil as long a time as possible.

Jan 1, 1938

By Joseph Jensen, F. W. Hertel

Many fields have been zoned by nature with shales and intermediate waters between oil zones. Limitations thus imposed have been the basis on which a field was developed. In contrast thereto, in the Ventura Avenue field, nature proved more generous. Always expecting to find such similar limitations, operators drilled deeper and deeper into the oil zone without finding any distinctive shale bodies other than the Gosnell shale and only one intermediate water, which became the point below which the final water shut-off of each well was made. Thus, on top of the structure, about 3300 it. of oil-bearing zone has been penetrated below this intermediate water—a distance of 4000 ft. below the Gosnell shale. At first it seemed that the greater penetration in the zone, the better the well. The error of this assumption became evident as time passed. Other pressing attendant problems requiring consideration also developed. In the spring of 1929, the Associated Oil Co., still having a large undrilled area, adopted a method for developing this land by dividing the oil formation into zones, so as to drill two classes of wells and to prepare for others, if conditions in the future justified or required such action. Wells now completed are considered as permanent completions in the zone or class for which they are drilled, and are not looked on as a ready means for deepening or accepted as a temptation for deepening to get some flush production quickly. Provision has also been made to avoid future water problems. The most striking demonstration resulting from such work is the fact that the top of the structure is far from being the point at which the largest oil recovery is made. Wells on the flank of the structure invariably produce with lower gas-oil ratios and secure much larger oil production. Zoning of Oil Sands The Gosnell shale separates the upper light 50 gravity oil from the lower 30 gravity oil below. As the light oil zone is of practically no importance at present, it is not being exploited. The development pro-

Jan 1, 1931

By Y. C. Kim, S. L. Barua

Underground coal mine planning has traditionally focused on the mine design aspects concerning safety and efficiency in the quest to produce low cost coal. Very little attention has been given to coal quality control aspects of mine planning at most US underground coal mines. With the enactment of the Clean Air Act of 1970, the generally high sulfur content of coal has become a major concern for the coal-fired power plants in the east. Similarly, the ash and the Btu content of coal are equally important for boiler efficiency. Coal mine planning must incorporate coal quality control aspects as well as traditional safety and efficiency aspects. According to an article in Coal Age (March, 1982), nearly one-half of the US coal exported to Europe does not meet the contract specifications regarding ash, sulfur and Btu contents. Although one of the reasons cited for this problem was "inadequate sampling at the US ports," the more fundamental cause probably lies in the inadequate quality control of run-of-mine (ROM) coal at the source. To perform adequate quality control of ROM coal, mines need predicted short-term in-situ coal quality information. Such predictions are generally based on whatever available sampling information is around the mine workings. Unfortunately, the closest sampling information, in the form of diamond drill hole assays, is often several thousand feet away in most underground coal mines and is inadequate for short-term coal quality prediction purposes. This is because the diamond drill holes (DDH) were traditionally placed in the coal deposit during the mine development phase to determine coal seam continuity and overlying roof conditions. They were not placed for short- term mine planning. A study was undertaken by the University of Arizona for the Homer City Owners in Pennsylvania to show that there is a need for more closely spaced samples, if the short-term coal qualities are to be predicted with any "reasonable" degree of accuracy. Prior to this study, a short-term quality prediction model, STPM, had to be developed. This model uses not only DDH, but also other sample information obtainable during face development work to predict the qualities of in-situ coal that are available in the immediate future.

Jan 1, 1985

By W. B. Clarke

It is the purpose of this paper to discuss briefly some of the recent developmellts in connection with the use of electrical apparatus for the mining of coal. For several years electricity has been employed extensively for the distribution of power, primarily for the operation of mine-locomotives and chain coal-cutters, and secondarily for motors driving pumps, ventilating-fans, rope-haulage, conveyors, crushers, auger-drills, coke-oven larries, etc. The severe and peculiar conditions which attend the development and distribution of power for the operation of coalmining machinery constitute a field to which the electricmotor seems to be especially adapted. The underground use of steam-engines, to any great extent, is impracticable for obvious reasons. The much higher efficiency of the electrical system is a potent argument in its favor as compared with compressed air, which, under ordinary circumstances, should only be employed for the operation of rock-drills and coal" punchers." The conditions in many mines prohibit the under-cutting of coal with a chain-machine; and the compressed-air " puncher," with its very low efficiency, is extensively employed. There have been no recent important improvements in the design and construction of the chain-machine, although, of course, minor changes are continually being made. More time and attention are being paid now than ever before to the details of mining-machinery, with the idea of eliminating the weaknesses which have been developed, and especially of facilitating repairs and renewals. Electric mine-locomotives are very extensively employecl for the haulage of coal on the main entries and the branchheadings; but in the majority of coal-mines the cars are still

Jan 1, 1904

By P. B. Bucky

THE purpose of this paper is to present a scientific method for deter-mining the proper span and shape of roof for safe and economical mining; at present, these two vital factors wherever pillars are left to support the roof are determined by local practice or general experience. To develop the method described here, experimental laboratory work was done. The arch adopted was a segment of a circle, a flat roof being considered an arch with an infinite radius. Hitherto, arches have been used underground without the background of stress analysis that generally precedes arch construction on the surface. In many cases results have not been as expected, because of the lack of knowledge of the factors affecting its strength and behavior. A theoretical and experimental study of arches should furnish informa-tion that will make it possible to design safe and economical surface structures as well as underground openings. For example, on the subject of mine drifts and tunnels, the present idea is that arching their backs increases their strength; this paper will indicate that this is not always true, and if it can be shown that under certain conditions arching becomes unnecessary an economic saving will result. In room-and-pillar work a question may arise as to whether arching the roof and gobbing the excavated material will result in timber saving, and a decrease in the dan¬gers from falls of roof. It is to be distinctly understood that each mine must be treated as an individual problem, and that answers to these ques-tions and many others can now be found after experimental laboratory data have been obtained.

Jan 1, 1934

By G. F. Loughlin

The subject of this lecture might well have been assigned to an economist or banker rather than to a geologist, but, as it was deliberately assigned to me, it is to be treated from a geologist's viewpoint. The term precious metals ordinarily includes the platinum group as well as gold and silver. Platinum, like silver, has had a great decline in price during the last few years, but has not been a medium of exchange and therefore has aroused comparatively little comment. Its relation to price level is like that of commodities in general, and will be dismissed without further comment. Of the two precious metals used as mediums of exchange gold, because of its adoption as the basis of most monetary systems and because of its threatened shortage in the near future; has been a subject of general concern to governments, financiers, and economists; silver, on the other hand, which has flooded the market of late has brought forth cries for help, direct or indirect, from producers and to a less extent from the largest users, especially China, whose purchasing power has been greatly curtailed, but it fails to arouse the interest that gold does. Many predictions have been made by economists, bankers, and others regarding future supply of gold and its effect on prices but the differences among these predictions are about as many as the number of prophets. Since gold is the standard by which the value of commodities as a whole is to be measured, it would seem that the greater the ratio of gold supply to commodities the higher the price level and vice

Jan 1, 1932

By A. B. Parsons

Perhaps this Index is the most useful volume the Institute has ever published. At least, it is likely to be referred to more frequently and by more people than any other single volume. It covers the contents of 27,058 pages of TRANSACTIONS in addition to special volumes, MINING AND METALLURGY and sundry pamphlets (T.P.'s) that were not subsequently included in the TRANSACTIONS. In the 54 years from 1871 to 1925 the Institute published 72 volumes; in the following ten-year period covered by this index it published 57 volumes, including TRANSACTIONS and special publications sponsored by the Rocky Mountain and Seeley Mudd Memorial Funds. These include the complete series for the Institute of Metals, Iron and Steel, and Coal Divisions, and all of the volumes on Petroleum Development and Technology. Indexing is an exacting task at best; it is something of an art. And a composite index like this, covering a wide range of subjects contained in volumes appearing over a period of ten years, presents added problems. Miss Katharine Lovell developed the system of indexing as the years went along, and did most of the original work. Mrs. Harriet K. Broughton, under Miss Lovell's direction, sorted and organized the accumulation of 33,000 cards on which the entries were made. For five years the Institute has needed a cumulative index badly; but until this year the Directors have not felt justified in authorizing publication. The delay has caused much inconvenience in the past; but to some extent this will be compensated by the great advantage of being able to find items covering the entire ten-year period in a single volume.

Jan 1, 1936

By Robert H. Chapman

During the past two years the writer has been traveling in the Lewis and Clarke timber reserve, locating the boundaries and reference-monuments for the Geological Survey. The Lewis and Clarke reserve lies in northwestern Montana. The region is very mouutainous, the main range of the Rocky mountains passing through it, dividing the waters of the Columbia and Missouri rivers. The mountains do not rise in one important and well-defined backbone, but in a series of parallel ridges, striking nearly northwest and southeast. Between these ridges, and, in general, parallel to them, are the drainage-systems. Beginning at the west, the rivers are the Swan, emptying into the Flathead lake, the South fork and the Middle fork of Flathead river, both emptying into the main Flathead river, which, in turn, empties into the lake of that name. The continental divide passes through the reserve from the southeast corner to the middle of the northern boundary, and the stream of most importance east of it is the Sun river, which heads well toward the north, and flows southeasterly and then eastward, and, emerging from the mountains, flows across the great plain of' the Missouri river. The southern boundary is drained by the Big Blackfoot river, flowing westward; the northern boundary, by the several branches of the Flathead river. The accompanying map (which is only a sketch, and does not represent the final work of the Geological Survey in this forest-reserve) shows clearly the parallel systems of drainage and ridges. The westernmost mountain range, the Mission, divides the great valley of the Flathead from the Swan river valley. The

Jan 1, 1900

By F. Julius Fohs

WITH portions of two coal basins within its borders and a few scattered fields already developed, the question arises: What is the future of Ken-tucky as an oil-producing State? Is the long list of failures due to lack of 'commercial pools, or unintelligent prospecting? A study of its beds and irregularities of structure points not only to a large waste of development money on unpromising areas, but also to the presence of a few structures well worthy of development. The surface rocks of Kentucky show in succession more than 4,000 ft. of Paleozoic sediments and more than 2,000 ft. of Cretaceous, Tertiary, and more recent deposits. Folding and erosion have brought these beds to the surface, where they have been observed and studied: in detail by my associate, James H. Gardner, myself, and others. This has given opportunity to observe the beds offering suitable reservoirs and having the proper impermeable covering; also the mapping of outcrops and outcrop lines, taken in conjunction with available well records, indicates that certain areas are worth testing, and with even greater definiteness shows areas which should be excluded, as devoid of possibilities. West of the Tennessee River, Cretaceous, Tertiary, and Quaternary sediments occur so that all trace of ancient folding is obliterated, the sediments overlapping unconformably Mississippian rocks. This area embraces 2,000 square miles, or one-twentieth of the area of the State, the Paleozoic rocks covering the remainder. Since there is nothing upon which to base the location of tests for oil and gas in the Cretaceous-Tertiary beds of Kentucky, the Paleozoic area will be chiefly considered.

Jan 3, 1915

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 zincking 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-silver 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.

Jan 2, 1915

By Rossiter W. Raymond

The manufacture of ferromanganese in the blast furnace having been the subject of considerable attention in the Institute, I beg to put on record a contribution to the discussion from a quarter hitherto not directly represented, namely, the St. Louis furnaces, near Marseilles in France, belonging to a company of which M. Jordan, a member of the Institute, is Managing Director. These furnaces commenced in 1862 to manufacture specular pig (fontes facettes) containing from three to six per cent. of manganese. In 1864 the regular production of spiegeleisen (fontes miroitantes), containing seven to ten per cent. of manganese, was inaugurated. At that time the Rhine was the only locality of this manufacture, and the Bessemer works of England and France obtained from Gernlany all their spiegel. From 1864 to the present time, the St. Louis furnaces have been advancing steadily the percentage of manganese in their product. From ferromanganese of thirty per cent. they had arrived, about two years ago, at a product containing seventy to seventy-five per cent., and for some time past they have been turning out what, as M. Jordan remarks, may fairly be Termed fonte de manganese, or manganese pig, instead of iron, since the percentage of iron it contains is not more than 8.5, while the percentage of manganese is 85, or ten times as great. This very high grade material has a peculiar appearance, entirely different from that of ordinary cast iron or spiegel. It is granular, and steely gray in color. The following analyses, communicated to the Sociètè des Ingenieurs Civils, by M. Jordan, show the composition of various products of the St. Louis furnaces:

Jan 1, 1879

By Bernard E. Fernow

About eight years ago a comprehensive study of American timbers was begun in the U. S. Division of Forestry with a twofold object. On the one hand, it was desired to deternliiie the working-qualities of our numerous economically important timbers, and to furnish reliable standards of strength. 011 the other hand, it was intended to get a clearer insight into the properties and behavior of wood in general, with a view of establishing more rational methods in its use, and to furnish data for physical inspectioil which would permit an intelligent application of the standards of strength, and place upon a rational foundation the so-called " factor of safety," which is at present a mere baseless guess. The first object, namely, the establishment of standards for any given species, requires a very large series of tests, since Wood is an exceedingly variable substance, so much so that in the same tree a variation of 50 per cent. in strength may be found; hence the greater need of rational data of inspection. So far, the insufficient appropriations and facilities at our disposal have permitted us to establish really reliable standards for five species of southern conifers only. These have been deduced from nearly 20,000 tests. Besides these, 10,000 other tests have furnished indicatious regarding some two dozen other species. This work is now entirely abandoned, waiting for more prosperous times. The study of wood in general, however, can be carried on with smaller means, and has this year yielded not only very interesting, but highly important results, which will soon be published in detail. It is the purpose of this paper to make to the Institute the

Jan 1, 1899

By Sir John Cadman

Since my previous review of the Persian fields, presented in 1929,' considerable progress has been made. The main feature of drilling development has been the delimitation of the Haft Kel field and its extensions. Although the limits have not yet been reached, a productive area of about 40 square miles has already been proved and it is now certain that the field will be of the same order of importance as the Masjid-i-Sulaiman field. Production to main pipe line from Haft Kel was begun in November, 1929, and to date about 4,500,000 tons have been produced. Normal production has continued from the Masjid-i-Sulaiman and Naft Khaneh fields. The search for oil in horizons below the main producing limestone is perhaps the most interesting and important exploratory drilling work in progress. Promising results have been obtained in the first well deepened in the Masjid-i-Sulaiman field with this objective, and the exploration of these lower formations is being continued. In this connection an allied program of geochemical research work on the nature of the oils and oil-bearing rocks of different horizons is at, present being undertaken. Masjid-i-Sulaiman Field Since the Haft Kel field was brought into production in 1929, production from Masjid-i-Sulaiman has been reduced in order to equalize to some extent the producing lives of the two fields. The production for the last four years has been as follows: m Approximate Equivalent in TonB Barrels 1929 5,434,071 38,038,497 1930 4,925,869 34,481,083 1931 4,248,086 29,736,602 1932 Approximately 4,500,000 31,500,000

Jan 1, 1933