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By AIME AIME

AT the seventeenth National Metal Congress, held at Chicago, Oct. 1-3, the Iron and Steel Division and Institute of Metals Division participated with the American Society for Metals, American Welding Society, and the Wire Association in one of the most successful meetings ever held. The total attendance at the technical sessions and the scope of and interest shown in the exhibits at the Exposition were greater than at any of the "Metal Weeks" since the depression began. The Iron and Steel Division held two all-day symposia and one general session. The latter, at the International Amphitheatre, Wednesday afternoon, was the only one poorly attended. This was attributable, at least partly, to the location of the meeting roan.

Jan 1, 1935

By R. W. H. Acherson

Blast-furnace flue dust is one of the most troublesome operating factors in the iron and steel industry. It is usually involved in all the unpleasant phases of blast-furnace operations. It adds to our aggravations until we are willing to spend large sums of money to keep it out of our stoves and boilers and more money to handle it again and again on one scheme or another to induce the furnaces to retain it without bad after effects. Several successful operators claim that it is useless to recharge raw flue dust because the furnace would never have blown it out if it had been suitable material for blast-furnace consumption. Most of us who have made persistent efforts to return raw flue dust to the furnaces have decided that it is very often false economy to do so. Yet some remarkable results have been attained at the Ohio Works of the Carnegie Steel Co. through recharging raw dust. The plant comprises six modern blast furnaces. Up to 1909, about 300,000 tons of flue dust had accumulated in stock piles. During the last 10 years, there have been recharged into these furnaces all of the flue dust recovered from the furnace operations, the entire stock pile of Rue dust, and nearly 80,000 tons of dust shipped from other furnaces of the Carnegie Steel Co. The results obtained arc. shown in Table 1.

Jan 1, 1922

By R. W. H. Acherson

Blast-furnace flue dust is one of the most troublesome operating factors in the iron and steel industry. It is usually involved in all the unpleasant phases of blast-furnace operations. It adds to our aggravations until we are willing to spend large sums of money to keep it out of our stoves and boilers and more money to handle it again and again on one scheme or another to induce the furnaces to retain it without bad after effects. Several successful operators claim that it is useless to recharge raw flue dust because the furnace would never have blown it out if it had been suitable material for blast-furnace consumption. Most of us who have made persistent efforts to return raw flue dust to the furnaces have decided that it is very often false economy to do so. Yet some remarkable results have been attained at the Ohio Works of the Carnegie Steel Co. through recharging raw dust. The plant comprises six modern blast furnaces. Up to 1909, about 300,000 tons of flue dust had accumulated in stock piles. During the last 10 years, there have been recharged into these furnaces all of the flue dust recovered from the furnace operations, the entire stock pile of Rue dust, and nearly 80,000 tons of dust shipped from other furnaces of the Carnegie Steel Co. The results obtained arc. shown in Table 1.

Jan 1, 1922

By Thomas Fraser, H. F. Yancey

The jig may be termed the standard coal-washing machine. Although exact figures on the relative tonnages of coal treated by the various coal-cleaning processes are not available, it is known that a large part of all the coal given special cleaning treatment is handled by jigs. This wide use of the jig warrants a special study of its performance. In this paper are presented the results of an analysis of work done by a three-compartment jig in treating bituminous coal from the Thick Freeport bed in Allegheny County, Pa. Certain systems of washing coal require sizing before washing, while others treat unsized coal. The prevailing practice, however, for the preparation of coking coal from the more easily washed coal is to treat an unsized or natural feed of about — 1 in. size and smaller. Under such conditions, the minimum size of particle that is beneficiated has long been and is still a matter of discussion and conjecture. In a careful laboratory investigation J?ngstl concluded that the practical limit of settling of fine coal is reached at from 0.02 to 0.008 in. On the other hand, Hancock2 has found that single-compartment jigs, used in preparing coal for the domestic market, usually allow most of the heavy (refuse) particles smaller than 1/4 in. to go into the washed coal. He also states that it is impossible with the ordinary coal jig to make any noticeable improvement in the quality of the coal finer than 20 mesh (about 1/30 in.). Because of its importance in coal cleaning, the work described in this paper was undertaken for the purpose of obtaining information on this subject, as a part of the general coal beneficiation program being carried out by the Bureau of Mines.

Jan 1, 1925

By Victor O. Homerberg, Dexter N. Shaw

A study of the correlation of the mechanical properties and of the microstructure with the heat treatment of 60-40 brass has been confined, heretofore, to the rolled or extruded material as received from the mannfacturer. The results obtained by Babson and Buhler,' Bengough and Hudson12 Stead and Stedman,3 and Brayton4 have been confined to the treatment of the material as received. No attempt was made to get the material into a given condition and then to work from this basis. To start with a given structure would have the decided advantage of making the work independent of the original condition, hence, to make the results reproduceable. In a previous paper, it was shown, in connection with the study of the transformation that occurs at about 470" C., that if specimens were quenched to produce the beta structure and then reheated, the beta would begin to break down, at approximately 200" C., into a very finely divided alpha. It was predicted that important results might be obtained if test pieces were to be given a similar double heat treatment and then tested for the mechanical properties as well as a study of the microstructure. The material used in the present investigation was a 3/4-in. round bar of extruded muntz metal of the following composition: Copper, 61.05 per cent.; zinc (by difference), 38.90 per cent.; lead, 0.05 per cent.; iron, trace; tin, nil.

Jan 1, 1924

By Yang Tsang Woo

I will endeavor to describe the methods of silver-mining and smelting employed by the natives in Mongolia. Modern methods have been applied there, but with little success; and, since they are familiar to most members of the Institute, I will simply mention that the failure was due to the high price of coke used in smelting the ore in modern furnaces, and to the unsuitable mill-machinery employed for concentrating the galena, which is finely distributed in the ore. The Jehol silver-mines are situated about 45 miles NE. of Jehol, the capital of Mongolia. They embrace two mines, 5 miles apart,—the Ku Shan Tze mine and the Yen Tung Shan mine. They were first worked by natives 50 years ago, about the time when mining was so flourishing in other parts of the world,—for instance, in California and Australia. The upper part of the vein is galena mixed with iron-stone, and is 2 to 4 ft. thick. At lower levels the vein is composed of silver-lead ore running between quartz-porphyry walls. Limestone, talc and black shale, colored by graphite, are found in other parts of the mine. Crystalline limestone is found 1 mile NE. of Ku Shan Tze. Granite is encountered in the Yen Tung Shan mine. Mining.—The native method of working the mines is most primitive. The same method may have been employed a thousand years ago. A small inclined shaft, 4 ft. by 4 ft., is sunk in the vein-stuff where the appearances are most favorable. Another shaft is sunk 20 or 30 yds. away, for ventilation. The shaft follows the vein in a zigzag fashion in whatever direction the vein appears to be richest. Timber is used only in soft ground. Where the ground is hard, the roof is cut into an arch-form. In some places, instead of using ladders, steps are cut in the rock, just wide enough to hold one foot. The deepest native workings are 400 ft. below the

Jan 1, 1903

By M. L. Fuller

During the last several years many papers have appeared dealing with the structure of highly polished metal surfaces. The awakening of interest in this subject is due to the applicability of the electron diffraction technique to the study of surfaces. The original theory of Beilbyl considered the surface of polished metals as of the nature of a supercooled liquid or a vitreous, amorphous solid. The electron diffraction effects from polished metals have been interpreted by rnany to be a direct experimental proof of the correctness of the Beilby theory. This interpretation has been strongly opposed by others, so that at the present time the subject is in an uncertain and controversial state. In the present paper new, and hitherto unpublished, electron diffraction effects from polished zinc are desrribed. These observations indicate that the polished surface of zinc is crystalline. Published Work Many papers2""10 have interpreted the electron diffraction evidence as proof of the Beilby amorphous theory. All investigators agree that highly polished metals give rise to two diffuse diffraction haloes, similar to those obtained by the diffraction of X-rays in liquids and vitreous solids. It is this similarity that leads to the amorphous-layer interpretation of polished metals. Strangely, the interatomic distances calculated from these haloes are very similar for the various metals investigated, in spite of a rather wide range of such distances in the crystalline and liquid states. The calculated atomic sizes are, furthermore, smaller than are experienced in the normal states of the metals. In spite of these anomalies, the amorphous-layer interpretation has been adhered to by many. One investigator, S. Dobinski," differs from the others in his experimental results. By polishing under benzene in order to avoid the possibility of oxidation, Dobinski obtains diffuse haloes of radii different from those previously obtained. He thus obtains a more rational quantitative correlation of the diffuse haloes with the amorphous-layer theory.

Jan 1, 1939

By M. L. Fuller

During the last several years many papers have appeared dealing with the structure of highly polished metal surfaces. The awakening of interest in this subject is due to the applicability of the electron diffraction technique to the study of surfaces. The original theory of Beilbyl considered the surface of polished metals as of the nature of a supercooled liquid or a vitreous, amorphous solid. The electron diffraction effects from polished metals have been interpreted by rnany to be a direct experimental proof of the correctness of the Beilby theory. This interpretation has been strongly opposed by others, so that at the present time the subject is in an uncertain and controversial state. In the present paper new, and hitherto unpublished, electron diffraction effects from polished zinc are desrribed. These observations indicate that the polished surface of zinc is crystalline. Published Work Many papers2""10 have interpreted the electron diffraction evidence as proof of the Beilby amorphous theory. All investigators agree that highly polished metals give rise to two diffuse diffraction haloes, similar to those obtained by the diffraction of X-rays in liquids and vitreous solids. It is this similarity that leads to the amorphous-layer interpretation of polished metals. Strangely, the interatomic distances calculated from these haloes are very similar for the various metals investigated, in spite of a rather wide range of such distances in the crystalline and liquid states. The calculated atomic sizes are, furthermore, smaller than are experienced in the normal states of the metals. In spite of these anomalies, the amorphous-layer interpretation has been adhered to by many. One investigator, S. Dobinski," differs from the others in his experimental results. By polishing under benzene in order to avoid the possibility of oxidation, Dobinski obtains diffuse haloes of radii different from those previously obtained. He thus obtains a more rational quantitative correlation of the diffuse haloes with the amorphous-layer theory.

Jan 1, 1939

By Franklin Bache

THERE seems to be in the public mind, and even in the minds of some coal-operators not experienced in mines subject to dust-explosions, a feeling that there has been something mysterious at the bottom of a number of recent American colliery-explosions. It has been declared in cases of accidents in mines regarded as particularly well equipped, in which every preventive precaution was said to have been taken, that the explosions were incomprehensible, and resulted from causes beyond the present knowledge of the practical coal-operator. But it is safe to say that no explosion has taken place which could not be explained by reasons well understood by most operators. The LT. S. Geological Survey Test Laboratory, recently inaugurated at Pittsburg for the reported purpose of investigating scientifically the matter of explosions in mines, will discover no new explanation of explosions. It call, however, co-ordinate the previous investigations of similar boards in England and on the Continent; and it may do a vast amount of good by promulgating widely, and in a form comprehensible by the most unlettered miner, certain facts and obvious deductions that cannot but have an effect in reducing the number and extent of the mine-disasters which, in the last few years, have been so terrible in frequency and magnitude. The only possible sources of explosions of any magnitude in coal-mines are : (1) explosives stored in quantity in the mine; (2) gases generated or liberated in the mine; and (3) coal-dust. Combinations of any of the three may, of course, take part in the result. The danger of any great loss of life from stored explosives alone is very remote. The simplest ordinary precaution forbids the presence, in one place underground, of any considerable quantity of explosives, and it would require an

Aug 1, 1909

By George A. Guess

The increasing demand for greater speed and more accuracy, in making daily assays of ores and products from mills treating material containing but very small quantities of lead and copper, has caused the older analytical methods to be supplanted by new ones devised to meet the needs of modern work. For " control" work in copper-analyses, I had, previous to the present equipment, introduced in my laboratory the ordinary electrolytic method, using hollow cylindrical electrodes; and with these I began a series of experiments in determining the lead-content of daily mill-samples and controls. The results, proving accurate and satisfactory, I then devised, with Mr. H. E. T. Haultain, a cheaper electrode than the ordinary jaCket-electrode, which costs from $15 to $20,—the expense of the older form making the installation of many units very costly. The form of cathode finally adopted as the most satisfactory, shown in Fig. 1, is cut from 0.001-in. platinum foil. It is 12.5 cm. long, and is divided into a blade 4 cm. wide and 6.25 cm. long, and a tongue 0.7 cm. aide and 6.25 long, the immersion area being 50 sq. cm. and weight 1.5 grams. The blade is first sand-blasted and then corrugated lengthwise, in order to impart the necessary rigidity. Strips of platinum foil 0.001 in. thick, 12.5 cm. long and 0.5 cm. aide, having a median corrugation, form the anodes. Three electrodes are used in each cell; one anode in the middle and one cathode on each side of the anode. These electrodes are connected to slotted aluminum terminals, in which they are held by contact pressure. The terminals are 5/16in. rods, projecting 2 in. horizontally in front of the wall of the cabinet; at the back the middle electrode (anode) is connected with one pole of the current, and the two outer ones (cathodes) with the other pole.

Jan 1, 1906

By Robert A. Cook

Among the new devices for cheapening the cost of material entering into the manufacture of iron is the mechanical drawing of coke, by which the coke from bee-hive ovens is extracted with a minimum of manual labor. About twenty years ago, an ordinary plate-conveyer was put in use at the plant of bee-hive coke-ovens owned by the firm of Bell Bros. & Co., near Middlesboro, England. This conveyer ran close along the front of the ovens, and carried the coke to the cars. The ovens were drawn by hand, and a very great saving in cost was secured, as one man could draw and clean out twice as many ovens after the conveyer was put in use—he having no forking to do, and the coke being carried away as fast as it was drawn to the mouth of the oven. The next step was further to eliminate hand-labor as far as possible; and Mr. Thomas Smith of the Thorncliffe Iron Works, near Sheffield, patented in 1891 the machine for drawing coke which I here describe. This machine, the outcome of several years of experimenting, has now been in successful use since 1891, and there are between twenty and thirty of them in operation at present, and others building. The machine, as may be seen from Figs. 1 and 2, consists of a wedge-shaped shovel of proper width and thickness, connected with a steel rack of sufficient length to reach the back of the oven. The rack is supported by rolls, and guided by a device operated by a hand-wheel, which directs the shovel in the oven. The rack is driven by a pinion on a vertical shaft carrying a bevel-gear on the upper end. This bevel-gear is driven by another on the engine-shaft. The engine is single-cylinder, with reversible gear; and engine and machine are mounted on a truck, which is propelled

Jan 1, 1897

By H. V. Churchill

There are two distinct methods of combating corrosive conditions. The first and most popular method is to choose a surface or material which will give adequate service under the specific and general conditions which are present. The second is a control or modification of the corrosive conditions to the end that metals and materials which would be attacked and corroded without such control or modification may be used. Under the first method of attack of the corrosion problem may be grouped such devices as the selection of metals or alloys which offer great resistance or the use of protective coatings such as paints, lacquers or metallic coatings. Such procedures are exceedingly useful. It is undoubtedly true that most of the problems of corrosion will be solved by recourse to this first method of attack. However, it must be remembered that there are many conditions in which metals are used where the choice of the particular metal to be used must depend upon other factors than corrosion behavior. Some of the factors which may govern the selection of metals for specific use are the physical and mechanical properties of the metals. But there is another factor which is of prime importance and that is relative price. It is the pressure of these factors of mechanical properties, physical characteristics, and relative price that has acted as the stimulus for the second methhod of combating corrosion. The producer and user of various metals is confronted with the fact that because of mechanical properties, physical characteristics, or price, the use of a particular metal is desirable even though the corrosion conditions are adverse to the use of the metal. In many cases, the successful use of the metal may be made even though it is impossible to protect the metal by coatings. This is rendered possible by control or modification of the corrosive media. Use of Sodium Silicate to Prevent Attack by Alkali Solutions This idea of controlling or modifying corrosive media is well illustrated by some recent experiences with aluminum. For a number of years collapsible tubes have been made of aluminum. Due to the ease with which aluminum is attacked by even mild alkalies, the use of such tubes

Jan 1, 1929

By H. V. Churchill

There are two distinct methods of combating corrosive conditions. The first and most popular method is to choose a surface or material which will give adequate service under the specific and general conditions which are present. The second is a control or modification of the corrosive conditions to the end that metals and materials which would be attacked and corroded without such control or modification may be used. Under the first method of attack of the corrosion problem may be grouped such devices as the selection of metals or alloys which offer great resistance or the use of protective coatings such as paints, lacquers or metallic coatings. Such procedures are exceedingly useful. It is undoubtedly true that most of the problems of corrosion will be solved by recourse to this first method of attack. However, it must be remembered that there are many conditions in which metals are used where the choice of the particular metal to be used must depend upon other factors than corrosion behavior. Some of the factors which may govern the selection of metals for specific use are the physical and mechanical properties of the metals. But there is another factor which is of prime importance and that is relative price. It is the pressure of these factors of mechanical properties, physical characteristics, and relative price that has acted as the stimulus for the second methhod of combating corrosion. The producer and user of various metals is confronted with the fact that because of mechanical properties, physical characteristics, or price, the use of a particular metal is desirable even though the corrosion conditions are adverse to the use of the metal. In many cases, the successful use of the metal may be made even though it is impossible to protect the metal by coatings. This is rendered possible by control or modification of the corrosive media. Use of Sodium Silicate to Prevent Attack by Alkali Solutions This idea of controlling or modifying corrosive media is well illustrated by some recent experiences with aluminum. For a number of years collapsible tubes have been made of aluminum. Due to the ease with which aluminum is attacked by even mild alkalies, the use of such tubes

Jan 1, 1929

Chairman James F. Kemp :—I call upon Prof. Albert Sau-veur to open the general discussion on the subject of sound steel ingots. Albert Sauveur, Cambridge, Mass.:—I believe that I have the privilege, this instant, of opening one of the most important, significant and far-reaching discussions ever held before this Institute. I believe that our talk this morning will be heard far and wide, not only on this side of the water, but also on the other side. Everywhere, in short, where steel is manufactured. I welcome the opportunity of expressing my mind in regard to the production of sound steel ingots, a subject about which I entertain Rome very decided opinions. I shall not attempt to discuss the relative merits of the various processes that have been described. I shall, on the contrary, confine myself to a general consideration of the important questions before us. So intensely do I feel regarding the production of sound steel ingots that I have put my remarks on paper in my desire to present my views. I have always remembered my astonishment, not to say dismay, some twenty years ago, when I beheld for the first time a steel ingot, a rail steel ingot, that had been split open from top to bottom. There was the pipe! There was an enormous cavity extending from a short distance from the top to nearly one-third of the length of the ingot; and when I was told that manufacturers seldom discarded more than one-tenth of the total length of the ingot it became evident to me that a large proportion of piped, and therefore, defective, or at least weak and dangerous, rails were manufactured; in fact, probably one rail out of six, nearly 17 per cent., of dangerous rails.

Jan 1, 1914

By Ottar Dragge, C. Danielsson, Bo Kalling

DISCUSSION, T. L. Joseph presiding L. F. Reinartz (Armco Steel Corp., Middletown, Ohio) —I would like to know, in the practical application of the Kalling process, what kind of a lining was used, how thick was the lining, and how much metal was treated at one time? S. Fornander (author's reply)—The rotary furnace is lined with a course of fireclay bricks 6 in. thick. This course is backed by 5 in. of insulation. The furnace has a capacity of about 15 tons. Mr. Reinartz—How was the ladle preheated? Mr. Fornander—As pointed out in the paper, the furnace was heated by a gas flame in the beginning of the experiments. During these first tests, however, the desulphurization was inconsistent. We think that this was due to the fact that iron droplets sticking to the furnace walls were oxidized by the gas flame. Now, the furnace is operated without preheating of any kind, and the results are much better. T. L. Joseph (University of Minnesota, Minneapolis, Minn.)—I might add one comment. This furnace was heated with a flame and for a time they had a little difficulty due to some residual metal in the rotating drum that would oxidize in between treatments and they found therefore, that it was very essential to drain the drum completely of metal so that they would not build up any ferrous oxide between treatments and they eliminated some of their erratic heats by maintaining those more reducing conditions. It was interesting to watch this operation. As soon as the drum started to rotate there was considerable flame, at least, at the time I saw it, that came out around the flanges, indicating there was quite a little pressure on the inside of the drum. W. 0. Philbrook (Carnegie Institute of Technology, Pittsburgh)—Is the reaction slag in the Kalling process liquid or solid, and how is it separated from the metal? Mr. Fornander—In the process there is no slag in the usual sense of the word. The lime powder does not melt during the treatment. After the treatment the lime is still in the form of a fine powder. It is separated from the metal by means of a piece of wood of suitable size placed within the furnace before it is emptied. D. C. Hilty (Union Carbide & Carbon Research Laboratories, Niagara Falls, N. Y.)—Dr. Chipman has given us some of his ideas in connection with a specific effect of silicon and silica on sulphur elimination and how silicon might interfere with desulphuriz- ing in the blast furnace. I wonder if he would like to elaborate on the possibility of a similar effect of silicon in the Kalling process? J. Chipman (Massachusetts Institute of Technology, Cambridge, Mass.)—Silicon does not interfere with the Kalling process. Anything that has strong reducing action is good for desulphurization. In these tests where the temperature was low compared to blast furnace temperatures, the silicon that is in the metal is a better reducing agent than the carbon. At high temperatures, carbon is the better. It is not the silicon in the metal that interferes with desulphurization, it is the silica in the slag. Mr. Joseph—I might add that the metal that was tapped from the drum after desulphurization was really at quite a low temperature. It was not measured, but I think it was well under 1300 °C, probably 1200" or a little above that. That was one of the difficulties, and I think there is no question about the fact that the Kalling process—in that it affects desulphurization between powdered lime, solid and liquid iron— is a reaction definitely between the solid lime and the liquid iron. E. Spire (Canadian Liquid Air, Montreal, Canada) — This Kalling process seems very interesting to us and after all it is only a mixing action that is taking place between the iron and the slag. We have attempted to do the same thing in another way. We have placed at the bottom of the ladle a porous plug through which we injected an inert gas. It can be nitrogen or argon. This plug is placed at the bottom of the conventional ladle and gas injected through the plug. That has appeared in our patent. To define this new type of treatment, I use the word gasometallurgy. I do not know if you like it, but it is a way of defining methods of treating metal using gases. What we do is exactly what is done in the exchange process in another way. We have a porous plug at the bottom with a high lime slag on top of the metal. Using this method, we have very good agitation of metal and slag, and with a small flow of gas, we can achieve a very strong agitation. For instance, in the 500 lb ladle, we use only 5 liters of gas a minute. We have an agitation compared to very rapidly boiling water in a pail. Moreover, the agitation can be controlled to create any amount of mixing desired. In a few minutes, with this method, the sulphur dropped from 0.58 to 0.11. These results have been improved since, and we have obtained results like 0.08

Jan 1, 1952

By Sherwin F. Kelly

In presenting this brief historical perspective, it is not my purpose to address myself to the geophysicists, to most of whom the story is already well known. My objective is to draw the attention of those who hold the belief that geophysics is something new, typically twentieth century, to the fact that fundamentally, whether it was known by the name of geophysics or not, the science is an ancient and an honorable one. It began many centuries ago, and our modern civilization and its commerce owe a great debt to its founders, who today are likely to be overlooked and their names forgotten. The word "geophysics" means the physics of the earth, and is descriptive of a science that in many ways bears the same relationship to geology that astrophysics does to astronomy. When dealing with distant stars or deeply buried rocks, the experimenter cannot reach them to obtain samples, which can be taken to his laboratory for study. He therefore exhibits the resourcefulness of Mahomet in the mountain episode, and makes the terrestrial globe or the cosmic universe his laboratory, studying the effects of distant bodies on certain "fields of force" which come to him across interstellar space, or through the rocks that make our earth. The application of these- techniques of the physics laboratory to the study of the stars is the science of astrophysics, and to the investigation of the earth is geophysics. Yet the origin of the most valuable contribution to the world's trade and commerce ever made by geophysics remains lost in deep obscurity. Unknown even is the country wherein lived the unsung genius who invented the first geophysical instrument, the mariner's compass! Worse yet, it is not certain whether this invaluable guide of man had its beginnings in Europe or in Asia. A Chinese legend tells of the Emperor Hwang-ti, who attacked his enemy Tchi-yeou on the plains of Tehou-lou in the year 2634 B.C., whereupon the latter magically raised such a fog that the Emperor could not pursue the retreating troops. Not to be outdone, the mighty ruler constructed a chariot that indicated the cardi-

Jan 1, 1940

By Sherwin F. Kelly

In presenting this brief historical perspective, it is not my purpose to address myself to the geophysicists, to most of whom the story is already well known. My objective is to draw the attention of those who hold the belief that geophysics is something new, typically twentieth century, to the fact that fundamentally, whether it was known by the name of geophysics or not, the science is an ancient and an honorable one. It began many centuries ago, and our modern civilization and its commerce owe a great debt to its founders, who today are likely to be overlooked and their names forgotten. The word "geophysics" means the physics of the earth, and is descriptive of a science that in many ways bears the same relationship to geology that astrophysics does to astronomy. When dealing with distant stars or deeply buried rocks, the experimenter cannot reach them to obtain samples, which can be taken to his laboratory for study. He therefore exhibits the resourcefulness of Mahomet in the mountain episode, and makes the terrestrial globe or the cosmic universe his laboratory, studying the effects of distant bodies on certain "fields of force" which come to him across interstellar space, or through the rocks that make our earth. The application of these- techniques of the physics laboratory to the study of the stars is the science of astrophysics, and to the investigation of the earth is geophysics. Yet the origin of the most valuable contribution to the world's trade and commerce ever made by geophysics remains lost in deep obscurity. Unknown even is the country wherein lived the unsung genius who invented the first geophysical instrument, the mariner's compass! Worse yet, it is not certain whether this invaluable guide of man had its beginnings in Europe or in Asia. A Chinese legend tells of the Emperor Hwang-ti, who attacked his enemy Tchi-yeou on the plains of Tehou-lou in the year 2634 B.C., whereupon the latter magically raised such a fog that the Emperor could not pursue the retreating troops. Not to be outdone, the mighty ruler constructed a chariot that indicated the cardi-

Jan 1, 1940

By J. E. Clennell

It is a common observation that the improvements introduced in practice since the first announcement of the cyanide process have been almost entirely mechanical. Although .a good deal of study land research has been devoted to the chemical problems [involved, the results obtained appear trifling in comparison. Few of the suggested modifications in the chemical treatment have come into practical use and those only in limited fields. Nevertheless, if we study the recent history of the cyanogen compounds from a somewhat broader standpoint, we shall find that considerable additions have been made, not only to our knowledge of their chemical properties, but also to their applications for industrial purposes. The present review of these advances naturally falls into two divisions: (1) processes involved in the treatment of ores; (2) manufacture of cyanides and other related compounds. Part I. Advances in the Chemistry of Ore Treatment by Cyanide In the attempt to extend the scope of the process, various ores have been encountered which contain gold and silver in such forms that they will not yield satisfactorily to ordinary methods of cyanide treatment. In some cases the difficulty is due to the excessive action on the solution of base metals present in the ore; in others, to the occurrence of minerals such as dyscrasite (the native alloy of antimony and silver), or a supposed oxidized manganese compound containing silver, which are either altogether insoluble in or very slightly attacked by cyanide. A particularly troublesome case is that of the so-called "graphitic" ores, containing carbon in some form which has the property of precipitating gold and silver already dissolved. Other efforts have been directed to improving extraction by electrolysis of working solutions, and by addition of various chemicals with or without electrolysis; to the diminution of cyanide consumption by "re-

Jan 1, 1916

By Frederic P. Dewey

It is common to blame irregular assay results upon volatilization and much has been written upon the subject, but there is no real evidence that, in a properly conducted assay, the loss of either gold or silver by volatilization is sufficient to affect appreciably the result, even when arsenic or antimony may be present. Bulk assays of flue dust from assay muffles have been published, but the data given are totally insufficient to even approximate the volatilization from a single assay; and such figures as we have indicate the volatilization to be extremely small. Diligent search in the literature and wide inquiry among assayers and instructors have failed to produce a single case where the litharge volatilized in making an assay has been collected and assayed for gold and silver. Having attempted to do this, with most indifferent success, I am not surprised that this has not been done. While various textbooks give volatilization as a cause of loss in cupella-tion, it may safely be said that in the rare cases where this volatilization is sufficient to affect appreciably the result it is due to excessive temperature. Percy' says "The loss of silver by volatilization during cupellation is very slight (unless the temperature has been much too high), and may be disregarded." This statement is repeated by the Beringers2 and Smith,3 who includes gold with silver. Mitchell4 says the litharge fume rarely contains over one ten-thousandth of silver. Campredon5 ays that at a proper temperature no silver is lost by volatilization. Primarily, excessive temperature may be due to too high general temperature in the muffle; but it may often be due to temperature localized within the bead by oxidation of the metals and this may be influenced by other causes than the general temperature. I have shown an ex-

Jan 1, 1921

By J. F. Wolff

DURING the past 4 or 5 years, much has been added to the detailed geologic knowledge of the Mesabi Range. This has not been in the direction of discovery of any new fundamental facts, but of detailed study, subdivision and correlation of different parts of the whole formation and of individual orebodies. Prior to this time, mining engineers in the district were so engaged with the commercial interests of exploring and developing orebodies that close geologic study and subdivision was done in only a few instances. The demand for refinements of work in this direction has caused caused extensive structural subdivision and correlation to he done in all exploration work during the past 4 years by the engineers of the Oliver Iron Mining Co. Such work has become a commercial necessity rather than a scientific refinement, and at the present time is being extended to all parts of the Range. In the summer of 1914, the author of this paper wrote a series of articles on the orebodies and special features of the Mesabi Range, which was published in the Engineering and Mining Journal, issues of July 17 to Aug. 7, 1915. Since that time studies of subdivision of the iron-formation have been extended considerably. The principle feature of this paper is the presentation of the subdivisions of the iron-formation. To this is added a discussion of the relations of the orebodies to the gentle folding and fracturing of the formation, and special features of the Range. The outline will he as follows: I. General geology. II. Subdivision of Biwabik iron-formation. III. Relation of orebodies to folding and fracturing of the iron-formation. IV. Special features. Acknowledgment is due to W. J. Olcott, President, and John Uno Sebenius, General Mining Engineer, of the Oliver Iron. Mining Co., for permission to use the information presented in this paper.

Jan 10, 1916