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By V. C. Wansbrough

A LUCID, thorough and powerful review of the impact of your tax laws on mining operations has already been presented by Granville S. Borden*. He has brought into focus and relief the pressure-points at which the shoe pinches most, has suggested some remedial measures, and enunciated much sound doctrine about the interrelationship and interplay of taxation policy and mining activity. Under the heading "What Every Lawmaker Should Know", he laid down the fundamental proposition that "the magnitude of our mineral resources varies inversely with the magnitude of the taxes levied upon them." With this, as with his other major premises, all mining men must be in hearty concurrence. There can be no doubt that a flourishing and expansive future for the mining industry in this country, in Canada, or anywhere else will depend on the thoroughness with .which these fundamental propositions are grasped by legislators, by national policy-makers and by public opinion at large.

Jan 1, 1950

By John D. MacFadyen

Subject paper unfortunately has some serious flaws negating the usefulness of the paper. The authors claim that sulfur is the major source of production problems in cement kilns. This is not the case. Sulfur is not a problem as long as the mole ratio of sulfur to alkali oxides is less than, or equal to, 1. This is attributed to the sulfur preferentially combining with the alkali oxides and not acting as a clogging agent due to the nature of the pre-heater vessels. Where the mole ratio exceeds 1, many methods are avail- able to eliminate or reduce the clogging problems such as using the preheater bypass or a precalciner with up to 100% kiln gas bypass. In non-preheater kilns, the presence of sulfates is hardly ever a problem anyhow. Thus, the level of sulfur in the fuel and raw material that might cause problems is not a fixed amount, but is predictable. The purpose of the paper is to discuss the economics of conversion of kilns in the Indonesian and Phillippine cement industries from oil firing to coal firing. This economic analysis has very little to do with the sulfur levels. Thus, the section of the paper on sulfates is actually rather meaningless. The economic analysis is also rather meaningless because the authors have failed to follow accepted economic analysis procedures by including interest charges. They have fallen into the trap of confusing financing with economic evaluation. When the accepted methods of economic evaluation are used, the return on investment increases to about 35%. In conclusion, the paper is not a meaningful contribution, and sadly, quite erroneous.

Jan 1, 1983

F. N. SPELLER (communication to the Secretary*).-It would certainly be interesting to know more about the heat balance in this practice, but there seems to be no doubt that the net result is a greater absorption of heat where roll scale is used instead of solid metal scrap. In the experimental heats referred to, about an equal weight of pig iron or steel scrap was replaced by roll scale. This caused a reduction of about one-third in the time of blow compared with a heat of the same

Jan 6, 1917

AlfreD H. Cowles, Cleveland, Ohio (commuaication to the Secretary*):—Mr.Gillette's paper and his deductions seem to me of the very greatest importance, if the validity of his conclusions and figures can be confirmed. His work seems to solve an unfinished problem that I attempted to solve on the same lines about two years ago, at a time when I was preparing a paper' on another subject for the American Electrochemical Society. The following paragraph is quoted from the paper referred to: "I feel convinced that a further study of the heats of combination now known for so many compounds, which merely express in other terms their voltages of disruption, will show us the allowance that must be made as a departure from unity in the case of each element, for the intrinsic charge of its elementary molecule, and thereby render possible the creation of a table of apparent relative atomic capacities for electricity, similar to the table of atomic weights. With the numerals of this table known, thermal reaction or energy-transformations will be read with the same ease that we now read and trace the shifting of mass

Jan 1, 1904

By L. W. Casteel

St. Joseph Lead Company's Southeast Missouri mines have been successfully converted to the use of ammonium nitrate and fuel oil as a blasting agent. This is significant to the company because it means a savings of a quarter of a million dollars per year. It is significant to the mining industry because of the unusual conditions involved and the methods and materials used to overcome them. St. Joe has been mining the low grade lead deposits of southeast Missouri since 1864. This ore occurs as disseminated galena in widely scattered pockets within the Bonneterre dolomite. The daily production of 20,000 tons is obtained from several hundred small, room and pillar stopes covering an area 10 miles long and five miles wide. Distribution of explosives and other materials is a real problem. Drilling in the stopes is done with air legs, column- mounted machines or jumbos, depending on the size and location of the stope. Drill hole sizes vary from 1 3/8-in. diam down to 1 1/8-in. Each driller charges his own holes and shoots them at the end of the shift. Numerous shafts provide natural ventilation which is supplemented in isolated areas by churn drill holes equipped with blowers. Water, in most stopes, is not a serious problem, although the mines do produce about 20,000 gpm.

Jan 5, 1962

By Thomas L. Kesler

THE Cartersville mining district, 35 miles northwest of Atlanta, Ga., has been of varying but continuous importance in the southern mineral industry during the past century. Noted chiefly for its production of brown iron ore, manganese oxide ores, barite, sienna, and magnesian limestone, the district and its environs have produced brick and tile clays, slate, gold, bauxite, and graphitic schist. Minor deposits of serpentine, sericite schist, copper ore, and red iron oxide have been prospected. The obvious deposits of brown iron ore, together with some associated specular hematite, were mined out years ago, although a little ore was left in the workings. Moderately steady production of sienna reached a peak about 1930, then declined rapidly. Manganese mining passed through a relatively active period from the World War to 1931, but has subsided to a small but rather constant output for the Birmingham market. However, the White Manganese Corporation has prepared for possible increased production by constructing a new washer capable of handling about 300 tons of ore per day. Principal activity in the district proper has centered for some years in the production of barite and magnesian limestone. GENERAL GEOLOGY Geologic relations of the ore deposits of this district are more or less similar to those of many Appalachian districts. The lowermost Cambrian formation, heretofore called Weisner1 in this region, supposedly partly or wholly equivalent to the Erwin and Hesse quartzites as recognized to the northeast, is overlain conformably by the Shady [+] formation, also of Lower Cambrian age. In the Cartersville district, the sedimentary rocks of these formations were folded with increasing intensity eastward, and were recrystallized.

Jan 1, 1940

By James M. Winston

When I began my career (the first assignment was mucking the "drainage" ditch) an experienced miner told me, "Remember son, happiness is a journey, not a destination. . . ." If you missed the 100th Anniversary of AIME in New York this year, you are missing the journey. There are not enough superlatives to describe the event. Especially since New York is "known to have it all." An Indefinable Plus There was a little something different at this meeting. I cannot explain what, but there seemed to be more of everything. There were more wives there this year-what a pleasure to see all the lovely women mingling through the conference- which was reflected through our own attire and mannerisms. In fact, everyone looked so great, we checked to see if it really was a convention of miners. You wives keep coming to all of the events, because so much is added by your presence.

Jan 1, 1971

By I. E. Puddington

The property of surface tension in liquids is said to have been known to Leonardo de Vinci in about 1500. Approximately'300 years later Thomas Young and others provided the ground rules relating surface tension to the wetting of solids and to the pressure drop across curved surfaces. In retrospect it seems remarkable that more than 100 additonal years were required for substantial technological use to be made of the-information. Thus super critical and freeze drying to avoid shrinkage of finely divided solids have only seen industrial use since the 1930's and doubtless additional possible applications will be equally slow in finding concurrence of conditions to make them attractive economically. The use of a second liquid phase that preferentially wets ,a suspended solid as a flocculant for that solid was pointed out in 1943 (1). Combining this phenomenon with mechanical energy to alter the morphology of the flocs or with surface chemistry to utilize it in the selective flocculation in mixed solids required more than an additional decade. A major stimulant in advancing surface energy based technology 'of suspensions was the report by D. I. Stock in 1952 (2) that mechanical agitation of a dry suspension of barium sulphate in benzene produced dense microspheres of the solid with highly desirable sedimentation characteristics. Investigation of this observation revealed that it resulted from small quantities of water in the system and mechanistically the phenomenon was identical with that reported in 1943.withthe addition of mechanical packing (3). Here then was a base from which to separate more efficiently suspended solids, to make small spheres from powders, to separate selected components from mixtures of finely divided solids or to break emulsions. Each of these possible branches of technology has been slow in developing on other than an experimental scale although considerable

Jan 1, 1979

By John A. M. E. Church

AT the last meeting of the Institute, a discussion arose upon the question, " Is them pressure in coke ovens ?" and many of the members seemed to think that the superiority of the Belgian furnace might be due to the fact that it is a completely closed chamber, in which the gases given off by the coal are, or may be, at more than the atmospheric pressure. It seems to me that this position is untenable, and that an examination of one of these ovens in operation will show, not only that there is no excess of pressure in the coke chamber, but that the contrary is true, and a partial vacuum exists. The Belgian or François oven consists of a rectangular chamber closed at the ends by sliding doors, and furnished with flues in the side walls and floor. The new charge is introduced at a time when the furnace is so hot as to cause immediate and copious discharge of the volatile constituents of the coal. The gases pass downwards through the side flues giving out their heat to the walls and thus to the coal. Underneath the floor air is introduced and the gases burn, producing intense heat. Heat is also reflected from the arched roof upon the coal which is therefore heated from all sides. The especial advantage which this construction was designed to secure is that no air is admitted to the coke-chamber. All the heat is produced by the combustion of the uncokeable gases, and the yield ought to be a maximum. It is so in fact, allowing for the imperfections inseparable from furnace construction and management. Sometimes the yield is in excess of the percentage indicated by assay, showing that

Jan 1, 1873

By H. M. Chance

THE failure of the carbonic acid gas method at the Kehley Run Colliery has given rise to a conviction of the inefficienoy of the process; but a careful survey of the facts, and of the conditions under which it was tried, will show that a fair trial of the method was not and could not be made at this colliery; its failure in this particular instance therefore, should not be held as evidence against the process. In itself, the method seems to be theoretically perfect, but in prac-

Jan 1, 1881

By Tell Ertl

An annual invitational address by an outstanding man in mining, geology, or geophysics who has contributed significantly to the progress of technology in these fields. IN 1954, the first year the award was conferred, Fred Searles, Jr., remarked, "The earlier years are the easiest." In this, the second year, it was easy to choose the outstanding mining engineer. Our conferee this year has been destined to mine. He comes from pioneer stock, and though a son of the American Revolution he is most proud that all four of his grandparents came to the Jordan River Valley of Utah the "first summer," which all Utahns will recognize as 1847. At the time of discovery of high-grade ore in Bingham, his grandfather, Archibald Gardner, had a crew of men getting out saw timber in the area. The first claim staked in Bingham Canyon was named the Jordan, and Bishop Gardner was the colocator of the claim as well as the man to record it. E. D. Gardner was born in West Jordan, Utah, in view of Little Cottonwood Canyon, the site of the Emma Mine. Park City in the Wasatch Mountains a few dozen miles to the east, and Tintic, not much further to the south, were developing their vast ore-bodies throughout his youth. As a boy he was near the present Midvale metallurgical area and could see the Lark and Bingham Canyon mine dumps and imagine the mining activities at Tooele, Ophir, and Mercur just over the nearby Oquirrh Range. He was 11 years old when the first car of copper ore was shipped from Bingham Canyon. It was not surprising that he attended the University of Utah and graduated with an engineer of mines degree. Five years with the Utah Apex in Bingham Canyon as chief engineer and assistant superintendent completed his training for the 44 years of unselfish and lightly rewarded service he was to give the mining industry as a Government engineer. All of us in mining are familiar with the great work he carried on and directed during the genera- tion he supervised the Southwest Experimental Station at Tucson. He has written scores of papers and books. His observations and experiments on drilling and blasting have led to the important improvements in this field during the past quarter century. Whereas those of us who consider ourselves widely informed about underground metal mining methods make hasty trips through a half dozen or dozen mines a year, our conferee has visited them all—not only the metal mines, but also coal and hundreds of nonmetallic mines, in the United States, Canada, Latin America, and overseas. His keen observations and analytical mind have resulted in an encyclopedic knowledge of mining and mines. His improvements in mining technology have been steady and predictable. His elucidation of mining problems to the many young engineers that have come under his guidance have made them grow strong and useful to his industry. When he chooses to stop, his influence will continue to expand and prosper because of the inspiration and dedication he instilled in so many of us. The profits from his ideas have been distributed throughout the mining industry. He has remained a technical man who felt that he could serve the mining industry best as a Government engineer. But he is the staunchest advocate of the belief that the public should gain from his work through private industry. This is not the first recognition E. D. Gardner has received. The Department of the Interior awarded him the coveted Medal for Distinguished Service in October 1949, and he received the Engineering & Mining Journal's Salute in March 1951. His friends who are presenting him the Daniel C. Jackling Award today know this great mining engineer simply as "Ed" Gardner.

Jan 1, 1956

Since I have had the pleasure of watching the development of this process very closely, I feel that I ought to say a few words on the subject, although I cannot add much to what Mr. Roe has already said. I wish, however, to bear witness to the hard work, persistence and skill which have been exercised during the past two years, and which have so well deserved the success attained. Those of us who remember the history of the past efforts in this line, such as the rotary puddlers, in which also some of us had a part, can easily appreciate the problems involved, and may well be skeptical as to the outcome. Such, at least, was my frame of mind when the process first came under my notice. Now, after having seen every heat, but three, of the many made, it really seems to me that a process and plant for the mechanical puddling of iron has at last been developed which is practical, economical and successful. Of course I do not mean by this that either the process or the machines are developed to their highest point, technically or economically, but that, in my opinion, these goals are in plain view, and that the difficulties which remain are such as will be overcome by developing the skill of the operator through practice ;

Jan 1, 1903

THE Joint Committee appointed to consider a Code of Ethics for Engineers recommends, after delib-erate consideration, that each participating Insti-tute or Society adopt the short simple Code of Ethics following this report. The Committee further recommends that the following method of interpreting and administering the Code be adopted by each participating Institute or Society after any necessary provisions have been, made in the Constitution and By-laws of the Organization. The President of each Society or Institute shall appoint a Standing Committee on Professional. Conduct, to administer the Code of Ethics. The duties of such a Committee shall be to interpret the Code and to render opinions on any cases of ques-tionable conduct on the part of members that may be submitted to the Committee. These interpretations shall be reported to the Executive Board of the Institute or Society who may approve these interpretations, or take such other action as may seem just and necessary. The reports of the Committee on Professional Conduct, when approved by the Executive Board, shall be printed in abstract and in anonymous form in the Institute's or Society's monthly journal for the instruction and guidance of fellow members. This Committee on Professional Conduct shall be appointed in each Institute or Society by the President holding office at the time of the adoption of this Code and shall consist of five member one appointed for five years, one for four years, a third for three years, a fourth for two years and a fifth member for one year only. Thereafter, the President then holding office shall appoint one member annually to serve for five years, and shall also fill any vacancies that may occur for the unexpired term of the member who has withdrawn. These appointments shall he made from among the older members of the Institute or. Society, so that advantage may be taken of their mature experi-ence and judgment. The Committee after appointment shall elect its own chairman and secretary. The Committee shall have power to secure evidence or other information in any particular case not only from the organization's own members, but if it should seem desirable, from men in other professions. The Committee may also appoint sub-committees to consider certain cases when deemed necessary.

Jan 3, 1922

By R. H. Richman, II Conard G. P.

AS part of a study of deformation twinning in bcc crystals, solid solutions of beryllium in iron have been found to twin profusely when strained slowly at room temperature. This note reports some crystal-lographic aspects of the operative mechanical twin modes in a quenched Fe-5 wt pct Be alloy. After melting twice under a partial pressure of helium, the alloy was homogenized, cut into pieces 7 to 10 mm on an edge, solution treated at 1130°C,1 and quenched. Debye-Scherrer patterns confirmed

Jan 1, 1963

H. D. HIBBARD, Plainfield, N. J. (written discussion *).-While this valuable and timely paper may not go to the root of the matter, it deals with many of the elements and factors involved. It might be taken as the engineer's solution of the case, starting with the assumption that steel is steel, while the tendency for a rail to have transverse fissures may, and probably does, depend, in part at least, on conditions met before it reaches the track. Admitting with the author that "brittleness of fracture in all grades of steel is characteristic of fatigue tests" we may yet look farther back to find out, if possible, why some rails and some steels are more prone to have transverse fissures than others, for it has been found that rails from certain heats of steel developed these fissures under a service which

Jan 3, 1918

Mark R. Lamb, Torres, Sonora, Mexico (communication to the Secretary*): I have read Mr. Merrill's paper with much interest, and cannot but accept his challenge as regards the cost of the clean-up at the Homestake mill. If I understand him correctly, the two men take the precipitates from the presses in about six hours, and do nothing towards refining them. If that is so, it would correspond to the work four men do here in about eight hours—that is, to clean the box and to place the precipitates in the driers. In order to make a fair comparison, the bullion in each case should be stated in ounces, since it is as diflicult to precipitate silver as gold, and our bullion is mostly silver. Bullion to the value of $50,000 is equivalent to a weight of about 2,500 oz. At our last clean-up eight standard bars, each 1,100 oz. in weight, were made, which equals a total weight of 8,800 oz'. Four men had the precipitates drying by 8 p.m. This plant, the Minas Prietas works of Charles Butters & Co., at Minas Prietas, has square-bottomed electrolytic vats, an arrangement which necessitates the handling of all the precipitates in buckets. The Butters plant at Virginia City, Nev., is equipped with conical vats, and probably could make a still better showing under similar conditions. Another point is that common labor only is required. (Ordinary laborer's wages at Minas Prietas are $0.70 gold.) I may say also that, except for the convenience of the refinery, the box could be cleaned monthly, instead of bi-monthly, at only a slight additional expense. The comparison, if made a few months ago, would have been much more in favor of the electrolytic process, as the tailings handled at that time contained a large quantity of copper, and the amount of zinc-dust required would have been enormous.

Jan 1, 1904

By H. S. Strouth

JAMAICA-bauxite and gypsum-but what else? J Does the Caribbean island have anything more to offer in the form of mineral wealth? One answer may be iron ore deposits which show enough promise to warrant exploitation in the near future by a company associated with Standard Ore & Alloys Corp. In addition, Jamaica is reported to have gold, silver, platinum, copper, lead, zinc, manganese, cobalt, and a great many nonmetallic minerals. Of these, only platinum has not been produced commercially in the past. Right now, Jamaican bauxite is getting most of the publicity, but not too long ago other mining operations were in progress. Lack of proper interest, insufficient roads, and scarcity of venture capital forced those mining properties to suspend production.

Jan 7, 1954

By William P. Blake

In a former paper read at the Washington meeting of the Institute, February, 1881,' I presented a general view of the geology and veins of Tombstone as then developed. Considerable additions have been made to our knowledge of the oredeposits since that date, nearly all the mines having been worked down to the general wster-level of the district. This water was a bar to further progress in depth and costly pumps were erected at the Grand Central mine and at the Contention. By the united action of these pumps the water was gradually lowered, not only in these two mines, but in all the important mines of the district. Pending a consolidation of interests, or an equitable distribution of the cost of unwatering, both pumping-plants were destroyed by fire, and the mines were closed

Jan 1, 1904

G. W. TRAER (author's reply to discussion*).-Prof. Parr's discussion develops two points, upon which it seems desirable to comment. First, as to putting through a large enough tonnage to secure economic operation. At each manipulation of each oven 1500 1b. (680 kg.) of coal will be charged and the resultant coke discharged from a like amount of coal. . Sixteen slabs will be discharged at each manipulation, each approximately 5 ½ in. by 11 in. by 6 ft. (14 cm. by 28 cm. by 1.8 m.). The operating schedule of a commercial plant, based upon our observations and calculations, indicates a "through put" of at least 12 tons of coal per day for each oven. We have made these figures conservatively and feel confident of materially exceeding them in a fully developed operating system. Our oven plant, with containers, will not cost as much as high-temperature plants of the same capacity. They do not require container equipment; but this is much more than offset by the cost of the great basal heat regenerative flues. Our operating requirements are quite susceptible to the application of mechanical devices and we believe our labor cost will be well within the necessary limit. Second, as to Fig. 1 in my paper, showing the specific gravity' of the tar. It Was not intended to show that the specific- gravity of -the tar rises With decreasing heat, since of course the contrary is the fact. One of the curves shows the relation between temperature and specific gravity and the other the relation between temperature and- yield. Our consulting engineer prepared the chart according to his customary method for showing two dimensions.

Jan 1, 1919

By H. F. Miller

Fox some years the prejudice against basic open-hearth steel for casting has been gradually decreasing. Yet many consumers and engineers still cling to acid steel for castings, because of their alleged greater freedom from blow-holes and sponginess. Acid steel has been used for this purpose much longer than basic steel; and the melters in acid practice had it well in hand when basic steel was first tried. Then the necessity of learning a new set of laws for the production of satisfactory basic open-hearth steel for castings became evident. The first of these laws, in my opinion, has to do with the furnace construction. The heat should be melted down as speedily as possible so as to prevent excessive oxidation. I have described in another article ' some furnaces designed by me, and having as one of their features the promotion of quick melting. Size of the Furnace. The hearth of the furnace, however, is a decisive factor in the production of solid castings. The manufacturer should know the size of the heats he intends to make constantly, and should have his furnace built for that size of heat. The hearth should differ in dimensions from that of a furnace making ingotr steel. That is, the bath should be deeper and should have less surface-area. A shallow bath permits the slag to come out soon after the steel commences to flow, and thus prevents the additions from going into the steel, or from becoming uniformly distributed in case they have been put in hurriedly. Under this head comes the very poor practice of making small heats in hearths of a much larger capacity. If into a 25-or 30-ton furnace only 12 or 15 tons of metal is charged per heat, the proportion of heats that will be wild, or show signs

Jan 1, 1913