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By G. F. Butterworth

The metallographic structures most frequently encountered in rifle barrels, and which are illustrated by the accompanying photomicrographs, fall naturally into two groups, distinguished by the method used to, produce in the stock a physical condition having the requisite properties. The fist group consists of "rolled" barrels; that is, barrels subjected to hot working by rolling in or near the critical range. In the second group, the stock, which is smaller in diameter than the first, is upset to form the butt end and is then heat treated by giving it a quench and a draw. These barrels will be referred to as " heat-treated " barrels. The structure of the rolled barrels resembles closely that of the same steel after annealing. There is the same network of excess ferrite outlining the grain boundaries, but the grains themselves are composed of sorbite rather than pearlite. The grain size is closely related to the rolling temperature. The critical-point curves of this grade of steel, which is approximately 0.50 to 0.60 per cent. of carbon and 1.00 to 1.30 per cent, of manganese, show a single very pronounced point between 1300" and 1350" F. (704" and 732" C.). Barrels rolled within this temperature range give an exceedingly fine grain, shown in Fig. 1. In fact, the grains may be so fine that, at a low magnification, they may be confused with the heat-treated structure shown in Fig. 6. A magnification of 500 diameters, however, will always resolve a rolled barrel into the characteristic structure shown in Fig. 2. As the temperature is increased, the grains are found to be larger. If, on the other hand, the rolling temperature is below the critical range, the structure previous to rolling will not be obliterated, the only effect of rolling being to elongate the coarse sorbite grains in the direction of rolling, Fig. 3. This distortion is greatest at the muzzle. Heat-treated barrels are quenched in oil from above the critical range, which should give a martensitic structure, Fig. 4, but the presence of some troostite in the martensite is frequently noted when the quench has not been sufficiently drastic, Fig. 5. The structure brought about by the subsequent draw is not so striking, though quite as typical. It is sorbitic or sorbito-pearlitic, and under a low magnification appears almost homogeneous, as in the case of fine grains of pepper and salt well mixed together, Fig. 6. This structure is substantially the same for all

Jan 1, 1920

By C. F. Willis

The problem of the curtailment of forces in large numbers does not often come to employment departments and is, therefore, a problem that many departments are not prepared to handle intelligently. Those companies that are able to measure the individual efficiency of each man would probably lay off men according to their individual ability, irrespective of dependents, citizenship, or other considerations. During the war when labor was scarce, the business of the employment manager in industry was hiring men and carefully placing them where they were best fitted to work. The careful selection of employees had developed to a considerable extent before the war, and was becoming a recognized science. In the last few months, however, the cancelation of copper contracts, the accumulation of large stocks, the necessary curtailment of production because the copper could not be sold, and the lack of any immediate prospects of' the copper market opening, have led to a universal reduction of forces, and the problem that industry now confronts is that of discharging rather than employing. The problem has been aggravated by the cancellation of contracts in many war industries with the consequent turning loose of hundreds of thousands of men, a great amount of unemployment, and the return of the soldiers and sailors. The problem has now become one of reduction of working force with the least hardship and the least injustice, and yet caring for the soldiers, sailors, and marines who have been in the service of the government for nearly 2 years, and are now returning to their pre-war positions. The Copper Queen Branch of the Phelps Dodge Corpn., operating at Bisbee, Arb., found it necessary, like all of the other copper companies of the country, to reduce its force materially. In making this reduction it was, after due consideration, decided to classify employees with respect to dependents, length of service, and citizenship. The question of individual efficiency or workmanship was not considered. Copper produced to sell at 26 c. a lb. has been selling at under 15 c., and very little copper is being sold at all. Practically every copper producer in the country has enormous stocks on hand, and it would be profitable,

Jan 1, 1920

By F. W. Denton

Much has been written about the possibilities of the Vermilion and Mesabi ranges of northern Minnesota as producers of large quantities of high-grade iron-ore. The Mesabi range in particular has attracted considerable attention on account of the proximity of the ore-deposits to the surface, which has been as-

Jan 1, 1898

By F. Osmond

When a metal (whether a simple substance, an alloy, or a compound) presents, in each of the smallest parts to which it can be redueed by mechanical division, a constant chemical composition, it is defined as chemically homogeneous. But chemical hombgeneity by no means necessitates mechanical homogeneity. There are no perfectly amorphous metals. Crystalline forces, on the one hand, and tensions or compressions, on the other band, determined by icequalities of temperature in the mass during heating or cooling, give rise in every metal to the formation of geometric elements of structure. These elements may, moreover, assume perfect crystalline forms, with their planes of cleavage; or embryonic crystalline forms, segregated in the midst of. a paste of confused organization; or pseudo-crystalline forms of expansion and contraction, like those produced in the drying of gelatinous precipitates or (most frequently) these different forms associated. 111 either case the adhesions between two adjoining structural elements, respectively homogeneous, may be very different from the interior cohesion of each of these elements. The mechanical properties of this complex aggregate cannot be simple, and, when it is submitted to strains sufficient to produce deformation, the results may be very different according to the type of structure or the manner in which it is affected by the strains. It may be fairly said that a metal does not present a single resistance to tension, or a single resistance to compression, etc., but in fact, at least theoretically, as many resistances to tension, compression, etc., as it may possess coexistent features of structure; only, in any single test, it is the weakest of the resistances involved which makes itself evident. For further explanation, let us imagine a cylinder A B (Fig. I), formed of two similar halves A and B, placed together upon their common base x y. Such a system evidently presents no resistance to axial tension, while it would resist axial compression like a single

Jan 1, 1894

By Albert Sauveur

The following propositions and corollaries are intended to present, as concisely as possible, some of the evidences gathered while studying the microstructure of steel. Each proposition is accompanied by photo-micrographs showing the structure of illustrative samples. But it must be understood that the special instances thus chosen for illustration are by no means the only ones on the examination of which the propositions are based. On the contrary, they have been taken almost at random among a great many, in some instances more than a hundred, similar cases. Proposition I. A slow and undisturbed cooling from a temperature x or higher produces crystallization. Plate L, Plate II., Fig. 1, and Plate V., Figs. 1, 2, 3 and 4 show the crystalline structure of several pieces of steel. Plate I. reveals this structure in the center of a slowly-cooled Bessemer ingot, 1.5 feet from the top. Plate II., Pig. 1, is from a small 2-in, square testingot of the same heat, slowly cooled. Plate V., Figs. 1, 2, 3 and 4 show the structure of different parts of steel rails. The original photographs were all magnified 70 diameters, and have been reduced in engraving to 63, or to 55 diameters, as shown in the plates. Proposition 11. Undisturbed cooling from an initial temperature lower than x is not accompanied by crystallization. Plate III., Fig. 5, shows the structure of a piece of rail-steel forged from a white heat until it had fallen to dull-red. The structure is almost amorphous. Practically no crystallization has taken place during the subsequent cooling. Corollary.—Pieces of steel finished at a temperature lower than x do not take a crystalline structure.

Jan 1, 1894

By Wheeler O. North

The United Eastern Mining Co.'s property is in the Oatman, Gold Roads mining district of Mohave County, Ariz. The mine and mill are 26 mi. (41.8 km.) southwest of Kingman, the nearest railway connection. The ore consists of a mixture of calcite and quartz with some andesite. The values, which are mainly gold, alloyed with approximately 34 per cent., by weight, of silver, are extremely fine so that fine grinding is a most important factor in extraction. The milling process, briefly, consists of single-stage, coarse-crushing, two-stage ball milling in cyanide solution, followed by combined mechanical and air agitation, and by straight counter-current decantation. The Merrill zinc-dust precipitation method is used to recover the values, and is preceded by the Crowe vacuum treatment of the solution. The most notable features of the plant are the absence of filters, and the use of short peb mills loaded with steel balls, for fine grinding. As originally designed, the capacity of the mill was to be 200 tons per day, although the grinding end was to be capable of handling double that amount. By adding extra agitators and thickeners and by some alterations to the grinding end, the daily capacity has been raised to 285 tons. This, it is hoped, may be increased to 300 tons during the warm months of the present year. Tonnage Milled per Day 1917 average....... 234; maximum month.... 272; minimum month..... 146 1918 average....... 253; maximum month,... 276; minimum month..... 217 As this article primarily deals with plant operations, those interested in the mechanical description are referred to the article by Mr. Otto Wartenweiler,1 the designing engineer, which gives the details and costs of design and construction. The following changes have been made since that article was published: Two special simplex Dorr classifiers have been substituted for the two duplex Callow screens and bucket elevator, which classified the Marcy discharge and returned the oversize for regrinding. Three Dorr

Jan 1, 1920

By J. A. Ede

The object of the writer is to call attention to a rather unique aggregation of economic products distributed over a line of succeeding formations about 3 mi. long, to be seen within a few miles of La Salle, Ill. Fig. 1 is an ideal section of the stratification exposed and exploited along a distance of 3 1/5 mi. in a southwesterly direction from the quarry of the Utica Hydraulic Cement Co. located near the historic site of Kaskaskia village to the Oglesby shaft at Oglesby. No attempt has been made to cover the whole field, special mention only being made (with the exception of two places) of the operations found along the course or parallel to the direction assumed in the ideal section. I have used Fig. 2, after J. R. Bent and De Witt Kelly, to locate the relation of the La Salle anticline to the coal mines of this district and to show the operation of No. 1 and 3 mincs of the Illinois Zinc Co. Anticline and the Rock Formations Owing to the structural deformation between La Salle and Utica, the older rocks of the state are exposed to the surface along the northern embankment and the bottoms of the Illinois River valley near the latter place. At; the Illinois Zinc Co. works, Sec. 16, Tp. 33, R 1, a well for water mas sunk 1828 ft. and samples taken every 10 ft. of the ground penetrated; duplicates were sent to Mr. Cady of the Illinois Geological Survey. A general compilation or synopsis study of this section is here presented. As the well is over 1 mi. west of the Western limb of the anticline, the section affords some reliable data. These samples were studied and interpreted by H. M. DuBois as Lower Magnesian, and by G. H. Cady as the Lower Magnesian. The results are given in Fig. 3. The most interesting geological feature of this district is the La Salle anticline. In 1865, Leo les Quereux, looking at Split Rock, asked how it happened that the upper coal measures overlie strata of the Lower Silurian and what has become of the formations which are generally found intermediate—the Upper Silurian, the Devonian and sub-carboniferous, and the lower member of the coal measures?

Jan 1, 1920

By G. T. Jackson

The Alaska Gastineau Mining Co.'s mine is located at Perseverance, about 4 mi. east of Juheau, Alaska. Its property consists of a group of claims, the lode system traversing these claims for a distance of 11,000 ft. (3352 m.). It is shown in Fig. 1. The ore deposits occur in what is known as the Juneau gold belt. This gold belt can be traced for about 50 mi. northwest of Juneau and 40 mi. southeast. It consists of a single band, several hundred feet wide, in which stringers and veins of quartz, carrying gold, occur in a slate formation near its contact with some altered volcanic rock known as greenstone. The Perseverance orebody consists of stringer lodes, having a strike northwest and southeast, dipping about 60° to the northeast. These

Jan 1, 1920

By Stanley C. Herold

A few hates on the occurrence and significance of mud volcanoes in Colombia may be of interest at the present time, owing to the renewed activity in geological exploration of the coastal regions bordering the Caribbean Sea. The best-known volcanoes are found a few miles from the seacoast. One is situated to the south of Puerto Colombia; the second, to the east of Cartagena near the village of Turbaco; and the third, near the village of Puerto Escondido south of the Sinu River. Others are reported in more inaccessible localities. Usually they stand 2 1/2 or 3 ft. (0.762 or 0.914 m.) above the surrounding ground at the crater, though several craters from 10 to 20 ft. -(3.04 to 6.09 m.) "apart will often build up an extensive mound at low gradient. The shallow mound may cover 1/2 or 3/4 acre (0.2 to 0.3 ha.) with an elevation of 12 or 15 ft. (3.65 or 4.57 m.) at the, center. The craters are formed of hardened blue clay; the inside diameters vary from 14 to 24 in. (35.56 to 60.96 cm.). The rim is continuous, except on one side where there is usually a cut 3 or 4 in. deep, thus allowing an overflow. The craters are filled to the' rim-cut with a thick mixture of blue clay mud and water, which is kept in agitation by escaping gas. Fig. 1 shows the bubble in the act of bursting and Fig. 2 the appearance of the surface of the viscous fluid a second or so later. The frequency of the explosions is determined by the weight of the column of fluid in the neck of the volcano, consequently, such explosions are not synchronous in a group of craters. Ordinarily, there arc two or three explosions in about 3 minutes. The supply of gas is small but steady and sufficient pressure must accumulate before the bubble can enter the column of fluid. The water is derived from the surface and enters the scdirnentary strata not far distant from the volcano. During long dry seasons, as the supply of water fails the volcano dries and geyser action ceases. The temperature of the muddy fluid is normal; the gas is dry and inflammable. - No petroleum products come with the gas. On the surface of the fluid, there is sometimes a dark brown streaky scum, which

Jan 1, 1920

By John A. Shelton

One of the heaviest burdens uselessly cast by our mineral land laws upon the holder of the title conveyed by a patent from the United States is due to the provision excepting known veins from land patented as placer. In many instances the expense of defending such titles from the assaults of the owners of lode locations made upon the theory that the veins so located were known to exist at the date of the placer application for patent has exceeded many times the value of the land in question. Neither the lapse of time, however long after the issuance of the patent. nor repeated adjudications by the courts serve to quiet such titles Or to prevent them from being questioned. In the passage of laws providing for the acquisition of title to the mineral lands of the United States, Congress provided that the title to known veins should not pass from the United States by a patent based upon a placer location. As construed by the courts, the law (Sec. 2333 R.S.U.S.) provides that the applicant for a patent upon a placer claim may, if any vein of sufficient value to justify the expenditure of money in its development is known by him to exist within the boundaries thereof, include in his patent application an application for patent upon the vein as a lode claim; and failure to do so is to be deemed a conclusive declaration that the applicant makes no claim to the vein nor to an area of surface ground extending for 25 ft. (7.6 m.) on each side of its middle or center. As to such vein and such area of enclosing surface ground under the circumstances stated, the title remains in the United States notwithstanding the issuance of a patent that purports to convey the entire surface of a described area and everything beneath it, excepting only the segments of veins the apices of which lie outside of such area. Such known veins with such area of enclosing surface ground are, of course, at any time, so long as they remain unlocated, subject to location and appropriation in the same manner as other. veins upon the public domain. The history of the operation of this law in one district will serve to illustrate its effect generally throughout the mining regions of the United States. In the Butte district, the mineral that first attracted the atten-

Jan 1, 1920

By Reinhardt Thiessen

Under sulfur in coal, is usually understood that form of sulfur which is combined with iron and known as pyrite. It occurs in the form of balls, lenses, nodules, continuous layers, thin sheets, or flakes, both in horizontal planes and vertical cleavage fissures. But pyrites also occur as very fine microscopic particles, or nodules, disseminated through the compact coal. This form has had but very little consideration. Finally, there is sulfur in coal in an amicroscopic form (not visible with an ordinary microscope), probably combined with the organic matter that exists in the coal. This form has had considerable attention from a scientific standpoint, but has probably not been recognized enough on the economic side. One or the other, or both, of these two latter forms may comprise the larger part of the sulfur content of coal, especially after it has been washed or otllerwise prepared for use. Pyrites in Microscopic Particles All coals that have been examined by the author contained a varying amount of sulfur in very small globules, or particles, of pyrite. These particles are seen in a thin [section as roughly rounded opaque dots, Figs. 1 to 10. When isolated, they are generally shown to be approximately spherical in shape, with a rough outer surface. They vary in diameter from a few microns to a hundred microns, the majority messuring from 25 to 40 microns; relatively few exceed the latter diameter. They are, therefore, very small objects. Their size is best appreciated by comparing the illustrations, in which they are shown. at a magnifiea tion of 100 diameters, with some known area like the period used in the ordinary printed page. The period is about 0.6 mm. in diameter, and . when magnified 100 times, will cover a circular area of about 2 1/2 in. in diameter, or all but the corners of the illustrations. The illustrations, therefore, represent an area about as large as an ordinary period, and the pyrite globules form but a small part of the total area. Very frequently a number of these particles are joined together in horizontal rows; oc-

Jan 1, 1920

By H. W. Young

Development of high-tension outdoor substations during the past few years has been due primarily to economic reasons. The demand for power in small communities could not be met with the conventional and Fig. 1.—33,000-VOLT step-up outdoor air-break switch and substation installation outside of a powerhouse generating at 2300 volts stepping up to 33,000. Twenty-one coal mines are supplied from lines leading from this installation. comparatively expensive indoor types unless the rate for service was materially increased. To prove that the problems lncident to development have been solved successfully, it is only necessary to point to the wide adoption of outdoor substations by utility companies. Passing at once to the question as to whether outdoor substations are applicable to

Jan 1, 1920

By E. G. Woodruff

The earlier struggles in petroleum geology were directed to solving the Qrigin and method of accumulation of petroleum. We are now fairly well agreed on those subjects. Most of us think that the great mass of petroleum commercially produced comes from plants or animals, or possibly from both. We are confident that the oil was not produced where it is now found but has accumulated in reservoirs of various kinds. The types of reservoirs are certainly variable but they just .as certainly follow definite geologic laws. Some of these types of reservoirs can be determined from surface study; others cannot. We know, too, that these types of reservoirs (largely structures such as anticlines, domes, and terraces) are much more widespread than the oil pools. In other words, there are many places where good sands and good structures exist but where oil is not found. It is the purpose of this paper, therefore, to attempt to analyze, from a regional standpoint, some of the conditions that control the presence or absence of oil pools and to group them in a regional way, hence the term "Petroliferous Provinces." The paper lays no claim to presenting new facts but attempts to group and classify the information that so many have expressed again and again. The essential factors for an oil field are petroleum, a reservoir material, and conditions under which the petroleum can enter the reservoir but cannot escape except through the drill holes. The paper will first discuss the source of petroleum as it occurs in definite regions, then the regional arrangement of reservoir strata, and finally the areal arrangement of structures. To have petroleum, there must be a source. Since living matter is considered the source of the petroleum, geological conditions must have been such that living organisms were abundant. Arid regions on the earth's surface have not given rise to living things in sufficient abundance to produce oil; similarly, too cold regions and saline inland lakes. The converse of this is that warm moist conditions must prevail to produce an abundance of vegetable matter. Before an area can be

Jan 1, 1921

By C. F. Willis

The time is no longer when a man can act as an independent unit; the appreciation of the interdependence of one man upon another has emphasized the importance of the social unit. Epidemics have made us recognize that even a man's health is not distinctly his own to control as he pleases. The physical examination of workmen previous to employment started with an effort to prevent the spread of tuberculosis, for tuberculosis may be detected in its early stages and cured. But it was soon found that many other diseases were detected and the saving of lives made possible. The physical examination does not mean the elimination of the unfit—on that basis it would utterly fail—but rather the measuring of a man's physical fitness and placing the man where he can do the best for himself, his fellow worker, and the company. Industry as a whole cannot expect to live up to the standard of physical examination set for the army, nor should it expect to do so, for in all branches of industry there are types of work that do not require the same amount of endurance as does army work, and the lacing of men with physical limitations in the work for which they are capable permits a higher average of physical fitness for the work requiring physical excellence. Objects of Physical Examination The objects of physical examination are: The early detection of illness, particularly at a time when a full restoration of health is possible; the protection of employees from infection caused by working in contact with contagious diseases; the discovery of a man's physical limitations, in so far as his possibility for rendering good service is concerned; assistance to the safety movement by eliminating association in hazardous occupations with men whose physical condition renders them likely to accident to themselves and others; and the lessening of time lost by sickness. Statistics issued by the United States Department of Labor show that 22.54 per cent. of idleness is caused by sickness, with an average number of 7.71 weeks idle; whereas only 1.66 per cent. is caused by acci-

Jan 1, 1920

By E. C. Harder, D. F. Hewitt

Since early in 1916, when it became apparent that the steel industry of the United States could not depend for the duration of the war on several important foreign sources of manganese and might have to depend entirely on domestic ores, the U. S. Geological Survey, with the assistance of several cooperating organizations, has made a comprehensive investigation of domestic manganese resources. The work has included field studies in a number of states well as annual, quarterly, and monthly canvasses among operators concerning current and future production. In order that the interested public might have access to the important results of the studies, preliminary reports concerning the field work as well as periodic summaries of production were issued as promptly as possible. Although numerous summaries of production l2, l3, l4 have been prepared from time to time for the use of the several boards and committees responsible for the conduct of the war, it has been thought for some months that those engaged in the industry, as well as others, might be interested in a preliminary summary of the accumulated geologic and production data. The cessation of hostilities, in November, 1918, probably detracts from the usefulness of much of the material that is here presented, but apart from the historic interest in the performance of an important industry in war time, there is a possibility that some of the conclusions may be helpful to those who continue to exploit domestic deposits, as well as to those who wish to measure the country's independence in mineral supplies. Appropriate final geologic reports are being prepared by the geologists who did the field work. The present authors, having done but a small part of the recent field work, acknowledge with great appreciation the use of preliminary and unpublished reports and the cordial informal cooperation of the following geologists in the preparation of this paper: F. L. Ransome, G. W. Stose, F. C. Schrader, J. T. Pardee, E. L. Jones, Jr., H. D. Miser, Laurence LaForge, J. B. Umpleby, Arthur Keith, F. J. Katz, and E. S. Larsen, of the U. S. Geological Survey. Field work in Virginia was carried out in cooperation with the Virginia Geological Survey, T. L. Watson, State Geologist; in Georgia, with the Georgia

Jan 1, 1920

By E. A. Holbrook

Research, primarily, is finding out the truth. Research applied to enigeering opens the door to new principies and processes, the application of which benefits mankind in a material way. The engineer believes that investigation instituted with the primary view of making the results directly applicable to the industries is the highest type of research. Coal is essentially the basis of modern industrial civilization; therefore, any considerable research pertaining to coal must link itself to the industry by practical application of the results of the research. In other words, all investigational work connected in any way with coal leads to conclusions that permit a better understanding of the origin, nature of occurrence, composition, better and safer mining, more careful preparation, or greater efficiency in utilization of coal. Modern engineering research has been fostered essentially by universities and in the laboratories of institutions of learning. Coal problems that lend themselves to solution in the laboratories have been first attacked and are perhaps the farthest toward solution. For example, a great amount of research work has been carried out with the various phases of chemistry connected with coal. On the other hand, the equally important problems connected with methods of mining have received but little attention, primarily because their solution involves the continued use of a great and expensive laboratory, which is none other than the mine itself. As many of the problems already solved have had chemistry as their background, so many of the problems unsolved have physics as their background; there are also unsolved problems that deal in coal economics. Even psychology must be called upon in future coal-mining research as a basis for solving those great problems that deal with human relationships. 'In general, considerable advance has been made in coal research dealing with chemistry, not so much progress has been made with problems having physics and engineering as a background, while there is a tremendous range of untouched problems that deal essentially with business and psychology. Research in coal mining is not a new development. In the chronicles of the northern coal trade as published in the Transactions of the North

Jan 1, 1920

By E. C. Potter

It is not the purpose of this paper to enter into the minutiae of a subject so vast, upon which volumes have already been written and volumes more might still be written, but simply to pass in review the characteristic features of that practice, which, dating from the blowing-in of the Edgar Thomson "A" furnace in 1879 and continuing down to the present day, has given to American blast-furnace operations a new significance. The blowing-in of " A" furnace marked the beginning of a new era in the science of iron-smelting if, indeed, it was not the very birth of science as applied to this industry in the United States. American blast-furnace practice in its generic sense and world-wide significance dates from that day, and really all that is valuable, all that is remarkable or worthy of discussion, is embraced in the experiences and achievements of the past fifteen years. Back of that we find only the dead level of mediocrity, or worse, a dispoition to " let well enough alone;" a general, almost universal, employment of " rule of thumb " methods. The application of scientific principles and methods was rare and, indeed, previous to the introduction of the Bessemer process in the early seventies, science had no place in controlling the operations of the American blast-furnace. The old practice consisted mainly in dumping raw materials in at the top of the furnace and tapping out iron and slag at the bottom, for the successful consummation of which the furnace-manager directed his best energies toward keeping the furnace as free as possible from "gobbing" with, alas ! but indifferent success. The burdening of the furnace was based largely on Mark Twain's receipt for " Johnny-cake," altered to suit the circumstances, viz.: a lot of ore, a lot of fuel and about a quarter of a lot of flux. The possible capacities of furnace-plants were not nearly realized. Enormous wastes were permitted, unheeded because not understood. In the use of fuel quantum suff. was always the rule. Increase of product was not thought of because it was not deemed wise or safe to attempt

Jan 1, 1894

By Geo. H. Ashley

The following paper is intended to be suggestive only, and to open the way for discussion and further observation. Its preparation was requested only two days before the time limit set for the submission of the papers comprising this symposium. Thus no time existed for detailed studies, so it is largely a memorandum of such facts as have come incidentally to the notice of the writer in the study of coal in the field. The field study of sulfur in coal has received very little special attention or description from coal student's. The presence of sulfur concretions is noted in hundreds of descriptions, and certain benches of a coal bed may be described as "sulfury" or the presence and position of sulfur bands may be noted in coal sections in connection with sampling. It may be accepted that some sulfur is present in all coal. The amount varies greatly in different regions, in different beds, and in the same bed in different areas. The anthracite of Rhode Island comes the nearest of any coal known to the writer of being free from sulfur, several analyses of that coal showing less than 0.1 per cent. Subbitumi-nous coals in Colorado in a few places have close to 0.2 per cent. of sulfur on the dry-coal basis and in other states subbituminous coals approach this lower limit. Bituminous coals seldom run under 0.4 per cent. of sulfur on the dry basis, though in a few places dry bituminous coals in Colorado and Washington have between 0.3 and 0.4 per cent. The better known bituminous coals have almost everywhere over 0.4 per cent. The best of the Pocahontas and New River coals run close to 0.4 per cent., but there is very little commercial coal in Pennsylvania, Ohio, Indiana, Illinois, Kentucky, or the other states, that runs under 0.5 per cent. on the dry basis. From these minimum figures, the amount will range up to 5 or 6 per cent. or higher if visible sulfur is not excluded. It must be remembered that the usual analysis of a coal bed is not intended to give the total proportion of sulfur in the bed but the amount in the coal after the removal of the more obvious and larger sulfur masses. Professor Parr has already pointed out that, chemically, sulfur occurs in several forms: as pyrite, organic sulfur, sulfates, and possibly as un-combined sulfur. Sulfur in the form of sulfates is commonly the obvious result of the weathering of pyrite and may be found in the coal within .

Jan 1, 1920

By Frederick Crabtree, A. R. Powell

When Professor Stoek asked for a paper on the above subject, it was too late to prepare by June 1, or near that time, one that would invoive any appreciable amount of experimental work or original research; but the suggestion was made that a review of the literature bearing on the subject might be submitted in good time, and that later this could be supplemented by any experimental data obtained during the summer, if experiments were carried out. In accordance with this suggestion, there are submitted the following notes on references found in the literature of recent years bearing on sulfur in gas. It is to be understood that, in general, these notes express the opinions of the authors whose papers are abstracted, not necessarily the opinions of the abstractors. Very little published information was found bearing directly on producer-gas sulfur, so this has been supplemented, in certain phases of the subject, by references to illuminating gas. Methods of analysis and processes for the elimination of sulfur from the gas are, without much doubt, very closely related in these two products. As in illuminating gas, sulfur is found in producer gas mainly as hydrogen sulfide, mixed with a much smaller and variable quantity of carbon bisu1fide.l The presence of minute quantities of other organic-sulfur compounds has been intimated, but no definite statement is made concerning these. The amount of sulfur present in producer gas is variable and depends on several conditions. The primary factor is the quantity of sulfur in the fuel, but the form in which the sulfur exists, the temperature of the producer, the air-steam ratio, and the efficiency of the scrubbing process are all determining factors. When the coal used contains less than 0.5 per cent. of sulfur, the sulfur in the gas will not exceed the quantity found in the average illuminating gas.2 Sulfur in producer gas may safely run higher than that in coke-oven gas, due to the lower-flame temperature

Jan 1, 1920

By S. W. Parr

FRom a study of sulfur with reference to its specific combination in coal, published as University of Illinois Bulletin No. 111, 1919, it is now possible to determine the various forms of this constituent with a good degree of accuracy. This fact suggests two questions: (1) Are the same analytic methods applicable to coke? (2) Is there any correlation between the forms of sulfur as it occurs in coal and the residual sulfur found in the finished coke? The answer to the second question might be helpful in answering a still further question as to what chemical route the sulfur travels during the carbonization process. While the special studies along these several lines are by no means complete, a few preliminary statements are herewith presented. They may, at least, prove suggestive of further possibilities from a continuation of research along these lines. There is no reason, chemically, why the analytic methods devised for coal should not apply to coke and a fair amount of experience in connection with such use affords confirmation of this statement. The procedure in the case of coal may be briefly outlined as follows: Combinations of sulfur as sulfate, or sulfides other than FeS2, are readily dissolved without disturbing either the pyrite sulfur or the sulfur that is in organic combination by means of dilute hydrochloric acid— 1 part of concentrated HC1 to 10 parts of water or approximately 3 per cent. acid. Digestion at 60" C. for 24 hr. insures the complete removal of the sulfur thus combined. In freshly mined coal the amount of such sulfur is very small; weathering processes, however, may very materially increase the amount of sulfate present. Sulfur in the form of iron pyrites, or marcasite, may be quantitatively removed without oxidation of the organic sulfur as follows: A dilute solution of nitric: acid is prepared having 1 part of concentrated HNO3 to 3 parts of water or with an approximate specific gravity of 1.12. The coal sample, ground to 100 mesh, is digested with this solution at room temperature for 3 or 4 days, filtered and evaporated to dryness, taken up with water, and acidified with hydrochloric acid. It is now ready for precipitation with barium chloride in the usual manner. If sulfate is present in the original sample to an appreciable amount, it should be removed by the procedure outlined above. It is not necessary here to give the methods for determining the two

Jan 1, 1920