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Mr. John J. Porter, Chicago Ill. (communication to the Secretary†):—Mr. Baker's account of his experiences with stock-distribution has been particularly interesting to me, as it

Jan 1, 1905

By John R. Don

This paper, under the title of "The Genesis of Auriferous Lodes from a Chemical Point of View, Illustrated by Analyses of Samples Taken from the Chief Auriferous Area of New Zealand, Victoria and Queensland, by John R. Don, D.Sc., M.A., Lecturer on Geology in the University of Otago, N. Z.," was submitted by the author with the frank confession that its length, covering several hundred printed pages of the Transactions of the Institute, would preclude its acceptance for publication in full. But the great value of the original work which it records rendered its rejection on that ground highly undesirable ; and, after correspondence with Dr. Don, it was agreed that the Secretary should condense the paper, subject to the author's approval, omitting what was not essentially connected with the original work reported. In the discharge of this laborious and difficult duty, the Secretary's chief trouble has been his regret to cut out the acute criticisms and admirable theoretical and historical summaries of Dr. Don on the general subject of the science of ore-deposits. It should be added, that the original paper has been returned to the author, with full permission to publish it through any other medium (due mention being made of the first publication by the Institute of portions thereof), and a cordial expression of the hope that the treatise, as a whole, may be thus published, to the advantage of science. The Secretary begs to add, that many of the portions necessarily omitted from this condensed version would constitute, in his judgment, interesting and valuable separate contributions. In attempting to condense this paper, it was necessary at the outset to cut out the tint three chapters, of which the following brief outline is therefore given. Chapter I., introductory in character, indicates the importance of chemical analysis in the investigation of the genesis of ore-deposits, emphasizing the value of Prof. Posepny's Institute paper, and especially of the discussion which it aroused, and stating in general terms the theories of "lateral secretion" and "ascension." Chapter 11. describes the scope of the investigation undertaken by the author, the chief purpose of which was to determine which of the above-named theories was favored by the evidence obtained. This evidence consists chiefly (though not wholly) of analyses of the country-rock taken at various distances from the auriferous "reefs," (a) on deep mine-levels; (b) in the surface or "vadose" region : and also (c) of underlying, neighboring or connected crystallines (granite, gneiss, etc.). In addition to these investigations, there is a separate inquiry into the question of the deposition of gold in marine basins, suggested by the fact that most of the gold in the lodes of Australasia occurs in stratified deposits. Chapter 111. discusses the principles and methods followed by the author in the examination of country-rock for the purpose described. After giving his reasons for believing that careful tests of carefully-chosen samples of country-rock taken at varying distances from the ore-deposit might throw light upon the question

Jan 1, 1898

Frank Firmstone, Easton, Pa. (communication to tlie Secretary*) :—Mr. Dilworth's formulas hnd tables are of course correct, and the extillction will occur as calculated, provided the nioney periodically set aside for sinking-fund be really invested and the interest compounded as assumed in the calculation. Actually, in alrilost all cases, such funds are used " in the business," in which case, in addition to the periodical charges for principal of the fund, additional charges must he made at the end of each period to cover the interest and compound interest on previous charges. The periodical charge for sinking-fund thus becomes a varyillg and continually increasing one until the date of extinction. On many accounts it scems more natural and conveniellt to make the extinction by a fixed periodical charge under the legal rule for partial payments,

Jan 1, 1911

For four years your Committee has been engaged in the study of problems connected with the educational preparation of professional geophysicists. The Present report represents the conclusions drawn from the investigations and deliberations undertaken since it was first organized. These studies have shown that the evolution of geophysics has proceeded along lines that differed from those marking the advance of classical geology. The latter science developed as a descriptive one, dealing with directly observable terrestrial phenomena, and the elementary, rational explanations that could be offered therefor. The fact that these phenomena were also chemical and physical in nature was seldom given more than passing acknowledgment. During the last half century, however, a new approach to problems of terrestrial phenomena has become of greater significance. This new attack has come through the sciences of physics and chemistry, as the people trained therein have investigated the facts of the earth as problems in their respective sciences. This development has been chiefly at the hands of European investigators, and European universities have long recognized it by establishing departments or institutions of geophysics. In the universities of North America, their arbitrary departmentalization into fields of physics, chemistry, astronomy, geology, etc., has prevented the academic recognition of such domains of science as geophysics and geochemistry. In consequence, the development of these subjects in the United States has been largely at the hands of nonacademic institutions, while the universities themselves are evidently in a state of confusion as to how the subject should be handled. In some places an attempt to teach geophysics is made in the physics department, in others in the geology department, in some in the engineering school, and occasionally as a cooperative effort; a Department of Geophysics is seldom found in North America. In some instances, proper academic plan. ning has been precluded by interdepart. mental jealousies, or by lack of appreciation of the significance of the subject. For the background upon which these conclusions are based, the reader is referred to reports previously issued or SPonsored by Your Committee. The "First Report of the A.I.M.E. Mineral Industry Education Division's Committee of Geophysics Education, 1939," summarizes the replies received to question-

Jan 1, 1946

For four years your Committee has been engaged in the study of problems connected with the educational preparation of professional geophysicists. The Present report represents the conclusions drawn from the investigations and deliberations undertaken since it was first organized. These studies have shown that the evolution of geophysics has proceeded along lines that differed from those marking the advance of classical geology. The latter science developed as a descriptive one, dealing with directly observable terrestrial phenomena, and the elementary, rational explanations that could be offered therefor. The fact that these phenomena were also chemical and physical in nature was seldom given more than passing acknowledgment. During the last half century, however, a new approach to problems of terrestrial phenomena has become of greater significance. This new attack has come through the sciences of physics and chemistry, as the people trained therein have investigated the facts of the earth as problems in their respective sciences. This development has been chiefly at the hands of European investigators, and European universities have long recognized it by establishing departments or institutions of geophysics. In the universities of North America, their arbitrary departmentalization into fields of physics, chemistry, astronomy, geology, etc., has prevented the academic recognition of such domains of science as geophysics and geochemistry. In consequence, the development of these subjects in the United States has been largely at the hands of nonacademic institutions, while the universities themselves are evidently in a state of confusion as to how the subject should be handled. In some places an attempt to teach geophysics is made in the physics department, in others in the geology department, in some in the engineering school, and occasionally as a cooperative effort; a Department of Geophysics is seldom found in North America. In some instances, proper academic plan. ning has been precluded by interdepart. mental jealousies, or by lack of appreciation of the significance of the subject. For the background upon which these conclusions are based, the reader is referred to reports previously issued or SPonsored by Your Committee. The "First Report of the A.I.M.E. Mineral Industry Education Division's Committee of Geophysics Education, 1939," summarizes the replies received to question-

Jan 1, 1946

By William Hurst

THE content of this paper is a presentation of the diffusivity theory for the calculation of the water drive on an oil reservoir in which b the history of reservoir pressure with time are the essential parameters for the determination of the rate and cumulative water encroachment into a field. The paper is divided into two parts-the main portion and appendix. The main body is essentially the application of the principles underlined here to actual field data. It consists of the work plots of the radial-flow case, and includes a discussion of an illustrated problem for which the water-drive calculations are treated in conjunction with the volumetric-balance equation. The appendix is a mathematical treatment of the linear, radial, and spherical cases of water influx into a reservoir.

Jan 1, 1942

By H. A. Hamza, N. E. Andersen

Emulsions have long occupied an important position in many industries. In the petroleum industry, where enhanced oil recovery techniques such as steam stimulation, flooding, etc. are being increasingly practiced, emulsions are very frequently produced. Characterization of these emulsions are an important prerequisite for monitoring and evaluation of the recovery processes. Emulsion properties will also determine the type of treatment required to separate and recover the oil phase. A variety of laboratory, pilot-scale and field-generated emulsions were characterized. Coulter technique results for size analysis are compared with microscopy (image analysis) and laser light scattering methods; Coulter determined oil contents are compared with gravimetric and volumetric methods of analysis.

Jan 1, 1980

By Philip B. Dettmer

In the last two decades we have witnessed many new developments in the art and science of mineral beneficiation. Competition and the pressures of inflation have caused operating managements to search for every possible way to squeeze out a few more cents savings per ton of product. One illustration of this is the trend toward the use of larger grinding mills. A few years ago a 1000 hp ball mill was considered a giant. Now we have many examples of successful grinding mill installations of 3000 to 4400 hp connected load per mill. The trend toward these larger mills is increasing every year, and we have not seen the upper limit yet. For example, three 6600 hp cement finish mills are presently being built for a plant in Missouri.

Jan 4, 1965

By G. M. Ikeda, J. G. Sibakin

An investigation was carried out to determine the variables affecting the coiling temperature of strip in the 56-in. hot strip mill. After statistical treatment, equations have been derived to determine the temperature drop between mill and coiler for both full spray (top and bottom) and top spray only practices. The individual influences of each variable in the temperature drop were derived for both practices. Limitations of the present practices were shown and adjustments in cooling for increased rolling speeds were suggested. A method of estimating the required number of sprays, their spacing, pressure, etc., to achieve a desired temperature drop is developed. MAXIMUM finishing temperature of a hot strip mill is mainly determined by the rolling speed, gage, and the temperature of the bar entering the mill. This finishing temperature may be limited by the maximum admissible coiling temperature in cases when either the cooling facilities on the runout table are not adequate or, more generally, when the cooling capacity of the runout table and the production capacity of the continuous mill are out of balance. Some time ago, the balance between these two factors was not considered detrimental to production. Recently, a new drafting schedule was introduced which increased the production rate, the entry temperature, and hence the finishing temperature. Thus, the restriction of the maximum specified coiling temperature became an important factor for many of the thicker gages. An investigation of the factors determining the coiling temperature may be, therefore, of considerable importance. A brief description of the available equipment will be a useful illustration of the techniques and methods used for this investigation. The 56 in. continuous hot strip mill is composed of six 4-high stands each containing two 221/2-in. diam work rolls and two 45-in. diam back-up rolls. Either of the last two stands can be used as the finishing stand. Which stand is used is dependent on the total percentage of reduction to be taken over the whole train, i.e., on the entry thickness and the final gage. The characteristics of these last two stands are given in Table I. Table I. Operational Characteristics of Nos. 5 and 6 Stands No. .5 NO. 6 Maximum voltage GOO 600 Power, hp 30(10 W00 I normal, kilonmp 4.35 3.73 Rpm of motor and rolls ISO 15 0 ITS to 300 Spettl ot strip, fpm 333 6 to 376T.2 103) to 2062 The speed of the finishing stand varies with the amount of reduction, strip width, and the exit gage. Finishing speeds in general use for varying gages are shown in Table 11. These speeds may change with an increase or decrease in the entry temperature of the strip. Even though the maximum speed of No. 6 stand is shown as 2062 fpm, this has so far never been attained,

Jan 1, 1957

By Benjamin L. Miller

The essential differences expressed by the different speakers participating in this symposium concern merely the relative emphasis placed on the subjects that are commonly included under the term "geophysics" and the branches of science that form the basis for investigations in this field. In order to appreciate the present situation it may be profitable to briefly refer to a few historical matters. One can find almost countless descriptions of geological phenomena long antedating the introduction of the title of "geology," which has been credited to Richard de Bury in the fourteenth century. Interpretations, when they were offered, were generally pure speculation. Only toward the close of the eighteenth century do we find theories developed as the result of observations and tested by additional observations. It is difficult to select and give proper credit to the individual who was particularly responsible for turning geology into a distinctly observational science. william Smith, who has been called the "Father of English Geology," certainly represents the period when observation was the only method used. As he traveled through the British Isles, "sometimes 10,000 miles in a year," he was continually making notes of his observations. Geikie says: "His plain, solid, matter of fact intellect never branched into theory or speculation, but occupied itself wholly in the observation of facts." William Smith, with others of his time, definitely laid firmly the foundations on which modern geology has been built. Field and laboratory observations can no longer be said to constitute the sole basis for geologic contributions but we have not laid aside the methods of Smith and his followers. It is folly to underestimate the fundamental value of the observational part of geology in the present. The objection to purely observational geology is that it is mainly qualitative and not quantitative, general and not specific. No one can deny this charge and probably there are few who do not welcome every method or process whereby we can put aside generalities for definite established values. Physics is the science that has particularly come to the aid of the geologist in this respect. Contributions of PhYsics It is not the intent of the writer to enumerate or to evaluate all of the contributions to geologic advance in the field of. physics. A few only are used for the purpose of illustration, When Clarence King, Director of the United States Geological Exploration of the Fortieth Parallel, invited Ferdinand Zirkel to study 2500 thin sections of rocks collected from the western United States, the use of the microscope came into general use. Zirkel's report was published in 1876. He was not the first to use transmitted light for microscopic rock determination, some work having been done by Henry Clifton Sorby and others some years earlier, but he was the first to put into general use this method. We may well daim that this

Jan 1, 1946

By Benjamin L. Miller

The essential differences expressed by the different speakers participating in this symposium concern merely the relative emphasis placed on the subjects that are commonly included under the term "geophysics" and the branches of science that form the basis for investigations in this field. In order to appreciate the present situation it may be profitable to briefly refer to a few historical matters. One can find almost countless descriptions of geological phenomena long antedating the introduction of the title of "geology," which has been credited to Richard de Bury in the fourteenth century. Interpretations, when they were offered, were generally pure speculation. Only toward the close of the eighteenth century do we find theories developed as the result of observations and tested by additional observations. It is difficult to select and give proper credit to the individual who was particularly responsible for turning geology into a distinctly observational science. william Smith, who has been called the "Father of English Geology," certainly represents the period when observation was the only method used. As he traveled through the British Isles, "sometimes 10,000 miles in a year," he was continually making notes of his observations. Geikie says: "His plain, solid, matter of fact intellect never branched into theory or speculation, but occupied itself wholly in the observation of facts." William Smith, with others of his time, definitely laid firmly the foundations on which modern geology has been built. Field and laboratory observations can no longer be said to constitute the sole basis for geologic contributions but we have not laid aside the methods of Smith and his followers. It is folly to underestimate the fundamental value of the observational part of geology in the present. The objection to purely observational geology is that it is mainly qualitative and not quantitative, general and not specific. No one can deny this charge and probably there are few who do not welcome every method or process whereby we can put aside generalities for definite established values. Physics is the science that has particularly come to the aid of the geologist in this respect. Contributions of PhYsics It is not the intent of the writer to enumerate or to evaluate all of the contributions to geologic advance in the field of. physics. A few only are used for the purpose of illustration, When Clarence King, Director of the United States Geological Exploration of the Fortieth Parallel, invited Ferdinand Zirkel to study 2500 thin sections of rocks collected from the western United States, the use of the microscope came into general use. Zirkel's report was published in 1876. He was not the first to use transmitted light for microscopic rock determination, some work having been done by Henry Clifton Sorby and others some years earlier, but he was the first to put into general use this method. We may well daim that this

Jan 1, 1946

By Clark Millison

The core recorder, a mechanical instr-ent for determining the exact depth at which core is recovered, drilled up or lost, is described. Examples of charts from the recorder are explained and interpreted. The uses of the core recorder are discussed. INTRODUCTION In the experience of geologists and engineers during coring operations on drilling wells, many will recall the times when a full core was not recovered and particularly when the requirement was urgent that they know exactly what part of the core was lost. To make this determination, the core recorder was designed. Its uses are many, and only the most obvious will be presented here. Although this discussion will be limited to drilling wells for petroleum, the core recorder can be used in any type of coring operation. The principle of the core recorder is the proportional reduction of the motion of core entering or dropping out of the core barrel to a stylus moving in such a manner as to record the reduced motion on a chart. The time element is registered on the same chart by the revolution of a clock which turns the chart drum. Thus the exact amount of core entering or dropping out of the core barrel is charted and the time of such entry or exit from the core barrel is precisely correlated to the depth at which the core is recovered or lost. Lack of movement of the stylus which is revealed by the continued revolution of the chart drum indicates that no core is entering the barrel. The principles are accomplished by an instrument placed inside of the core barrel. A cylinder which contains the clock and mechanical apparatus has a diameter smaller than that of the core barrel. Near the top of the cylinder is an eighteen hour clock which turns the drum that contains the chart. Near the bottom of the instrument is a serrated wheel which by friction against the inside of the core barrel is turned as core enters or drops out of the barrel.

Jan 1, 1949

By Clark Millison

The core recorder, a mechanical instr-ent for determining the exact depth at which core is recovered, drilled up or lost, is described. Examples of charts from the recorder are explained and interpreted. The uses of the core recorder are discussed. INTRODUCTION In the experience of geologists and engineers during coring operations on drilling wells, many will recall the times when a full core was not recovered and particularly when the requirement was urgent that they know exactly what part of the core was lost. To make this determination, the core recorder was designed. Its uses are many, and only the most obvious will be presented here. Although this discussion will be limited to drilling wells for petroleum, the core recorder can be used in any type of coring operation. The principle of the core recorder is the proportional reduction of the motion of core entering or dropping out of the core barrel to a stylus moving in such a manner as to record the reduced motion on a chart. The time element is registered on the same chart by the revolution of a clock which turns the chart drum. Thus the exact amount of core entering or dropping out of the core barrel is charted and the time of such entry or exit from the core barrel is precisely correlated to the depth at which the core is recovered or lost. Lack of movement of the stylus which is revealed by the continued revolution of the chart drum indicates that no core is entering the barrel. The principles are accomplished by an instrument placed inside of the core barrel. A cylinder which contains the clock and mechanical apparatus has a diameter smaller than that of the core barrel. Near the top of the cylinder is an eighteen hour clock which turns the drum that contains the chart. Near the bottom of the instrument is a serrated wheel which by friction against the inside of the core barrel is turned as core enters or drops out of the barrel.

Jan 1, 1949

By A. Faber du Faur

At the request of some of the members to whom I have shown a collection of specimens of sulphur from southern Utah, I herewith present some notes relating to the mines and the method of extracting the sulphur from the ore. In preparing these notes I have borrowed from a paper by Prof. G. vom Rath, published in the Neue Jahrbuch fur Mineralogie, vol. i., 1884, dated Salt Lake City, December, 1883. The Cove Creek sulphur-bed, now worked by the Dickert & Myers Sulphur Co., is in Beaver county, near the line of Millard county. It was first discovered by Mr. Ferdinand Dickert in 1869 ; other beds in the same neighborhood mere found by him from 1872 to 1875, making altogether 22 mining claims. The want of railroad communication prevented the early development of these claims; but in 1883 Mr. F. Dickert put up a plant for extracting sulphur from the ore, which proved a perfect success; and in 1885 the property was transferred to a stock company organized under the laws of Utah. The railroad station nearest to the Cove Creek mines is Black Rock, on the Utah Central Railroad, 204 miles south from Salt Lake City, and about 26 miles west of the mines. The road from Black Rock to the mines passes through desert and lava-bed, to the road leading from Kanosh to Beaver, which latter road it joins near Cove Creek fort, a square stone enclosure, erected by the Mormons for protection against the Indians. Cove Creek fort is situated near the eastern limit of a plain bounded on the west at a distance of about 12 miles by the Mineral range, and on the east by the Sulphur mountains, forming part of the Tushar mountains. To the northwest the plain runs into the Sandy desert. About 3 miles from the fort rises a solitary hill about 1000 feet above the

Jan 1, 1888

By A. F. Taggart, F. E. Beach

The flotation process for the concentration of ores is a method by means of which one or more of the minerals in the ore (usually the valuable ones) are picked up by means of a liquid film and floated at the surface of a mass of fluid pulp. Here they are separated from the other minerals, which remain immersed in the body of the pulp. In general, the minerals which are floated are sulphides of metallic luster, but some other minerals of metallic luster such as graphite and some sulphides with adamantine luster, such as sphalerite and cinnabar, are amenable to treatment by the process. The importance of flotation lies in the fact that it is primarily a "slimes process" by means of which the particles of valuable mineral, too fine for efficient gravity concentration, are saved with a high percentage of recovery. Recoveries in the mills treating low-grade copper sulphide ores have been advanced 10 to 20 per cent. by the installation of the process and similar increased savings have been accomplished by the same means in mills treating sulphide ores of zinc and lead. When finely ground ore containing sulphides mixed with a siliceous or earthy gangue is brought gently onto the surface of a body of water, in a direction forming an acute angle with the surface of the water, a considerable portion of the sulphide constituent of the ore floats on the surface of the liquid, while the gangue sinks. This is the so-called film flotation, exemplified by the Wood and Macquisten processes. When gas bubbles are introduced into a fluid pulp composed of finely ground ore and water, to which has been added (1) a small amount of certain oils, or (2) a small amount of certain acida or acid salts, or (3) a small amount of certain alkalis or alkaline salts, or (4) a small amount of a mixture of oil with acid or alkali, the sulphide particles in the ore are brought to the surface on the gas bubbles. These collect in a froth

Jan 1, 1917

By C. G. Maier

COMMERCIAL processes of lead softening directly involve the behavior on fusion of mixtures of the oxides of antimony and lead, and the vapor pressures of these materials. Practically no quantitative data have been available for the discussion of lead softening from the point of view of the fundamental metallurgy of the process. The Pacific Experiment Station -of the United States Bureau of Mines, in cooperation with the University of California, in the course of its program of study of the fundamental properties of oxides and sulfides, recently made vapor pressure measurements upon the various forms of pure antimony trioxide.1 When these measurements were considered in connection with the softening and "fuming" furnaces which are often used for lead purification, an unexpectedly anomalous condition appeared. In brief, this anomaly consisted in the fact that in certain softening furnaces, where lead bullion of approximately 1 per cent antimony content was being treated at a temperature of approximately 1300° F., no appreciable volatilization of antimony occurred, there being produced only a "skim" containing from 15 to 20 per cent Sb, 65 to 60 per cent Pb, as mixed oxides. In the "fuming furnaces," where the temperature was only about 1400° F. and where an accumulation of "skims" from the primary softener was being treated with certain other antimony-containing materials, a considerable volatilization of antimony as oxide occurred; an "impure" skim of some 60 to 65 per cent Sb and 10 per cent Pb was also produced as mixed oxides. The latter material cannot be suitably treated in hearth-type or softener furnaces. The essential chemical difference between the first and second step is the customary use of some reducing material (such as petroleum coke) in the later operation. An obvious interpretation of the effect of coke in facilitating the fuming of the antimony is the supposition that the antimony may be reduced to metal, and volatilized as such. This supposition is improbable, however, when it is realized that a slight extrapolation of the vapor-

Jan 1, 1932

By Benjamin Gildersleeve

Uniquely colored, thin-bedded quartzite is quarried between Crossville and Crab Orchard in Cumberland County, Tenn. It is produced in all sizes up to the limits of transportation from beds usually ranging in thickness from less than Vi in. to 6 in. The stone is very resistant to wear and weathering and is marketed throughout the country for many different purposes in exterior and interior construction. The annual production exceeds 36,000 tons, valued at nearly $1,000,000. THE building stone of the Crab Orchard District is a fine-grained, thin-bedded sandstone which is so strongly cemented by silica that it may be classed as quartzite. As used in this paper the term building stone includes dimension stone, rubble, ashlar, flagstone, and rough broken stone. The Crab Orchard District is in the central portion of Cumberland County, Tenn. It is named from the town of Crab Orchard near which the stone was quarried first for industrial use. The heart of the district is an area of some 1200 acres from 1 to 3 miles east of Crossville which is 70 miles west of . Knoxville and 125 miles east of Nashville (fig. 1). At the present time, there are about 15 quarries worked by companies and individuals. Geology: The Crab Orchard District is on the Cumberland Plateau, or Cumberland Mountain as it is called frequently. Most of the area is characterized by a comparatively even surface from 1800 to 2000 ft in elevation and is drained by streams flowing into the Tennessee River. Included in the district are two quarries located 7 miles west of Cross-ville and this area is drained by tributaries of the Cumberland River. Most of the quarries are located near the 1800-ft contour which is just below the general upland surface. The surface rock over most of the district is the Rockcastle sandstone which has a thickness of about 260 ft.1 It is the topmost of the six formations of

Jan 1, 1951

By Benjamin Gildersleeve

Uniquely colored, thin-bedded quartzite is quarried between Crossville and Crab Orchard in Cumberland County, Tenn. It is produced in all sizes up to the limits of transportation from beds usually ranging in thickness from less than Vi in. to 6 in. The stone is very resistant to wear and weathering and is marketed throughout the country for many different purposes in exterior and interior construction. The annual production exceeds 36,000 tons, valued at nearly $1,000,000. THE building stone of the Crab Orchard District is a fine-grained, thin-bedded sandstone which is so strongly cemented by silica that it may be classed as quartzite. As used in this paper the term building stone includes dimension stone, rubble, ashlar, flagstone, and rough broken stone. The Crab Orchard District is in the central portion of Cumberland County, Tenn. It is named from the town of Crab Orchard near which the stone was quarried first for industrial use. The heart of the district is an area of some 1200 acres from 1 to 3 miles east of Crossville which is 70 miles west of . Knoxville and 125 miles east of Nashville (fig. 1). At the present time, there are about 15 quarries worked by companies and individuals. Geology: The Crab Orchard District is on the Cumberland Plateau, or Cumberland Mountain as it is called frequently. Most of the area is characterized by a comparatively even surface from 1800 to 2000 ft in elevation and is drained by streams flowing into the Tennessee River. Included in the district are two quarries located 7 miles west of Cross-ville and this area is drained by tributaries of the Cumberland River. Most of the quarries are located near the 1800-ft contour which is just below the general upland surface. The surface rock over most of the district is the Rockcastle sandstone which has a thickness of about 260 ft.1 It is the topmost of the six formations of

Jan 1, 1951

By Edward Keller

Under the title, Labor-Saving Appliances in the Works-Laboratory, I published a paper1 in which mas described how multi-manipulations in a works-laboratory and in the furnace-room of an assay-laboratory, can be condensed into single manipulations by applying the proper mechanical devices. For example, I now deposit ill, or withdraw from, a muffle a set of 48 cupels as one unit. The front row (8) of these are blanks or heaters; the other 40, when they have attained the proper temperature in the muffle, are charged simultaneously with the 40 lead-buttons. Three manipulations here accomplish an operation which by the generally customary method requires 136, and this number is only limited by the size of muffle and cnpels. This operation is an enlargement of what I have already described in my former paper, and Fig. 1 shows the improved implements. In the paper referred to I described a gold-silver bead parting-bath, which is the last of the devices used in regular sequence in practice. This bath mas designated as being convenient, but mas not a labor-saver properly. Fig. 2 of the present paper shows a new device. Instead of the original tray, there are now sectional holders for the test-tubes, each having a wooden handle on either end, so that the holders ma?-be removed from the boiling bath, and the acid or water poured oE from each set of tubes (in this case, 7) without waiting to cool. The tubes, held in place by clutches, as shown in Pig. 3, rest in holes in the base-strip, having a smaller diameter than the tubes. Each holder is stamped at either end with a number, so that the bath becomes further useful by permitting several men to use it at the same time without interference. Apart from the handles, the holders are made of sheet-copper.

Jan 1, 1911

By Frank Soulé

Secretary E. H. Benjamin, of the California Miners' Association, has proposed and begun, in co-operation with the testing laboratory of the University of California, at Berkeley, a series of tests which should prove of great interest and practical use to all persons making extensive application of steel wire cables, and especially to miners who run them in deep mines. Mr. Benjamin is endeavoring to obtain pieces of cable both new, and old and worn, from every deep mine of importance on the Pacific Coast, together with all the data obtainable concerning their manufacture and particular use. Pieces from each sample will be broken ill the laboratory before mentioned: and as far as possible the effects of winding around drums or pulleys ; of sudden starting and stopping when loaded; of heavy shocks, and of the general wear and tear of the cables, will be ascertained by these tests. The Olsen testing-machine of 200,000 pounds capacity will be used to break the cables, and the rupturing force, in different instances, will be applied slowly and also rapidly, in order to make the tests comparable as far as possible with the practical use of the cables themselves. All information and data available should be obtained for each specimen sent to the laboratory, the name of the manufacturer, the date of making, strength of cable when new and unrusted, as well as the circumstances and conditions of the practical use of the cable. Having this information before us, we shall be able to tell, approximately at least, the effects of age, rust, wear and tear, shocks, etc.; and perhaps be enabled to draw the line of limitation beyond which it would be no longer safe to use a cable of known manufacture. Moreover, by means of such tests we may, perhaps, he able to recommend worn cables for other uses, less severe in character, thereby prolonging the life of their effective usefulness. When we consider the great number of miles of steel cable now in use, and of the greater number constantly being manu-

Jan 1, 1900