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By Robert H. Richards

Very little has been published recently on this subject in the mining journals or proceedings of societies. The attention of experts has been diverted perhaps by the demands for pan amalgamation of refractory ores. Yet free milling ores occur in many localities, and it may be interesting to have on record some data as to details of running a small test-mill, especially as details of results do not seem to be accessible to stndents and investigators. Küstel, in 1863, under battery amalgamation, dismisses the subject by stating that "amalgamation on copper-plated platforms, troughs, and other copper fixings" is " very imperfect, and mostly abandoned." J. Arthur Phillips says, in 1867, under placer mining : " A well-amalgamated copper plate is considered as effective for

Jan 1, 1880

By Albert Sauveur

It is delightful to read a technical paper like that of J. E. Johnson, The Effect of High Carbon on the Quality of Charcoal-Iron, presented in October, 1912, at the Cleveland meeting of the American Institute of Mining Engineers.' The clear, simple, and straightforward manner in which he describes his experiments and results makes you feel as if you had been, so to speak, at his elbow during the course of his investigations, while his method of procedure is so rational that you can fairly anticipate each step in the logical sequence of the tests performed. The following notes suggested by Mr. Johnson's paper are presented here in the hope that they may help, if only a mite, towards the final solution of a problem of considerable scientific and industrial importance. Physical Properties of Cast-Iron us. Its Ultimate Composition. Mr. Johnson writes that " an investigation along the lines of consumption showed that different irons have different characters totally independent of their analyses," and he declares that " the presence or absence of these elements [meaning carbon, phosphorus, silicon, and manganese] alone will not account for all, scarcely for a half, of the facts which have long been known." He further tells us that some foundries have " proved, by the most irrefutable tests, that they could take a certain iron of a given analysis and produce certain results," while with " another iron of the same analysis they could not produce these results at all." I feel confident that every experienced and thinking metallurgist will readily believe Mr. Johnson's statements and will share his views in regard to the hopelessness of inferring the

Jan 1, 1914

By H. W. Turner

In addition to the deposits mentioned by Mr. Lindgren? the following may be noted: 1. In the " Dardanelles quadrangle," of the map of the U. S. Geological Survey, 3 miles NW. of Tower Peak, there is a considerable mass of quartzite, marble, and dark, fine-grained. gneiss. At the edge of the coarsely crystalline white marble, having a width of about 400 ft., is a white schistose rock, which,

Jan 1, 1904

By J. M. Callow

The selective action of oils for lustrous minerals was first disclosed by Haynes in 1860. In 1885, Miss Carrie Everson elaborated this idea and also disclosed the fact that acid increased the so-called selective action. Her patent called for oils, either animal, vegetal or mineral, also for an acid or salt. The process was tried out on a practical scale in Baker City and Leadville, in 1889, and failed: first, because, as has since been shown, of the unsuitability of the ore to flotation; and second, because the invention was too far in advance of the times. Then followed the Elmore brothers, first with their bulk oil processes and later with their vacuum method. The basic principles of oil flotation were undoubtedly covered by the above inventors, the work done since their time being merely a building up on ground work laid by them. Different kinds of oil, different quantities of oil, and all the varying degrees of agitation, were all exemplified and practiced by them in one phase or another, and the developments that have since been made are but elaborations of the fundamental principles laid down by Haynes, Everson, and the Elmore brothers. In 1902, the Potter-Delprat process was developed in Australia. In this process no oil was used, the mineral being raised by the generation of gas, brought about by the introduction of acid into the pulp. The mineral particles appeared on the surface of the separatory vessel, in the form of a scum or froth, buoyed up by minute gas bubbles attached to them. This no doubt first gave the suggestion of gaseous flotation. In 1902, also, Froment, an Italian, was granted a patent in which he combined violent agitation with oil and gaseous flotation, the gas being generated within the pulp, in much the same way as in the Potter-Delprat process. In the same year, Cattermole came out with a unique method. First, the pulp was emulsified with a small quantity of oil, by violent

Jan 1, 1916

By J. M. Callow

THe results obtained by pneumatic flotation throughout the country on all classes of ore, and the tonnage now being treated by this particular method, speak for themselves. Its advantages over the so-called agitation process are now established by facts and data from practicc. The comparative efficiency of a rapidly revolving paddle, as a means for aerating an ore pulp, and of a cyeloidal or turbine blower for the same purpose, would seem to be so obvious as to leave no room for discussion. Practitioners in this art are to be congratulated on the acquisition of the valuable literary contributions that have recently been made on the theory of flotation by Messrs. Ralston, Van Arsdale, Taggart and Beach, and others, and the very valuable and able articles by Messrs. Laist and Wiggin on "Flotation Concentration at Anaconda, Mont.," by Dr. Rudolf Gahl on the "History of Flotation at Inspiration," and by David Cole on "The Advent of Flotation in the Morenci District." It is not within the province of this article to attempt an answer to the various issues raised in regard to the theory, or to defend the one advanced by me a year ago. But since discussion usually benefits the profession, a reply will be made to some of the statements made by the last-named writers. CoMPABATIVE SENSITIVENESS AND ATTENDANCE Concerning the article, "Flotation Concentration at Anaconda, Mont.," by Laist and Wiggin, a little explanation is in order. It should be stated that, with the exception of about 24 days at the end of the testing period, the Callow experimental plant at Anaconda was not run under my direction. This perhaps accounts for some of the concIusions drawn on page 499 of the descriptive paper. The conclusion that the use of acid seems to be of considerable advantage, calls for some comment. While the tests conducted by the Anaconda Copper Co. do show acid to be of considerable benefit, this is a consequence of using acid sludge as a flotation agent. My belief has always been that the Anaconda

Jan 1, 1917

By W. P. Blake

Forging under the hydraulic press, which was introduced by Haswell in the year 1861, at the machine shops of the Imperial State Railway Company of Austria, has since been greatly improved, so that at the present time there are very few parts of machines which cannot be produced in this way, and at no greater cost than iron castings. The process is now used at Vienna chiefly for such parts of locomotives as cross-heads, link-bars, axle-box frames, etc., especially where the form is intricate, and there are many angles and projections. These objects weigh from 50 to 150 lb. or more, and it is claimed for them that they are not only much cheaper than ordinary forgings, but are much more regular in form and stronger. The results which Mr. Haswell has attained, after years of patient experimenting, were well shown in the Austrian Department of the Vienna Exhibition by a collection of the pressed objects in iron and steel, just as they left the moulds, with some of them cut asunder longitudinally and the surfaces etched, so as to show the internal structure or direction of the grain. Through the courtesy of Mr. Haswell and his son I saw the hydraulic presses in full operation at the works, drawing down large Bessemer ingots, cutting them up into blocks of convenient size, and forming various park of locomotives. They have two large hydraulic presses in use; the largest, with a piston 24 inches diameter, gives 1200 tons pressure, and the second, with an 18-inch piston, gives 600 tons pressure. The pressure in the pumps is 600 atmospheres. The action is vertical; the piston descends upon the work, and for forging ingots is armed with a hammer-like head. An ingot of No. 7 soft Bessemer steel, which was forged in my presence, weighed 2030 lbs. One end being placed upon the anvil, the piston is brought slowly down and crowded into the mass as if it were putty or dough, forcing it each way, but chiefly in the direction of the length of the ingot, this being the narrowest section of the anvil and hammer. The piston is then raised and the ingot is moved forward for a second squeeze, and so on, until the first half of the ingot has been reduced in thickness, when it is turned on edge and the operation is repeated. The ingot is then turned end for end and forged until the whole length has been re-

By Clarence R. Claghorn

Few facts relating to the Bernice anthracite coal-basin have been published in our Transactions, and little is known among engineers in general of the character and composition of the coal found in that basin.

Jan 1, 1889

By J. M. Hartman

ONE of the most important subjects to the blast-furnace engineer is a thorough knowledge of the conditions affecting the temperature in the different portions of the furnace. All efforts to decrease the consumption of fuel and improve the working of the furnace must be based upon it, and I may, therefore, be permitted to place before you the results of my observations, and detail the conclusions to which they have led me. Tracing the thermic conditions from below upwards we have at the bottom of a blast furnace making No. 3 iron a temperature of 2900' F., which increases slightly to a point a little below the tuyeres. In the immediate vicinity of the tuyeres the temperature is somewhat lower, owing to the entering blast; but a short distance above the tuyeres, where all the oxygen of the blast has been converted into carbonic acid, the highest temperature in the furnace must be attained. This carbonic acid is, however, almost as soon as formed, converted by the glowing coal into carbonic oxide, a process which absorb, heat, reduces the temperature, and provides the active agent for the reduction of the iron ores. In its ascent the hot carbonic oxide gradually parts with its heat, first melting the descending iron and earthy materials, which drop down to the hearth of the furnace. The limit of this zone of fusion is rather sharply defined, and the temperature above this zone suddenly decreases. In its further ascent the hot gas drives off the carbonic acid from the limestone, which causes a further absorption of heat, and finally the gas escapes at the top, at a ternperature of about 250' F. if the furnace is working well. These changes of temperature I have attempted to represent graphically,

Jan 1, 1880

By William H. Shockley

Though China has been widely explored by mining engineers during the past dozen years, comparatively little has been published concerning its mineral resources. The few moilographs scattered through the transactions of various societies contain far less information than the private reports made to the numerous syndicates which have sent out engineers. The best general account of the geolopy and mineral resources of China is to be found in the works of von Richthofen,' a remarkably gifted observer. The observations recorded here in this paper were made in the service of the Pekin Syndicate (which has kindly given me permission to publish them), during the first months of 1898, among the coal- and iron-fields of southeastern Shansi. This is one of the largest anthracite-regions known, the area being

Jan 1, 1904

By G. S. Brooks

The tendency of the oxides of such metals as aluminum, zinc, chromium, and calcium to form compounds at high tempera tures with iron oxide is well established by past investigation. Data of this reaction, as developed in laboratory research, have been contributed by Burleigh, Hofman, and Wells, in America, and by many others abroad. A partial bibliography of the subject is appended. From these authorities we learn that the ferric oxide here has the function of an acid, giving in the case of ZnO a zinc ferrite, with a normal composition of ZnOFe2O3 This formation of zinc ferrite particularly affects the success of such processes as leaching or magnetic separation, and thus becomes practically important to the metallurgist. But the meager existing data do not entirely agree; and quantitative results from muffle-practice are conspicuously absent. Furthermore, it being of some general importance to the zinc smelter in both roasting and reduction, the following few notes of operations oil a commercial scale are contributed: I. Physical Properties of Zinc Ferrite. As formed for the most part synthetically by investigators, zinc ferrite exhibits characteristic physical properties, such as octahedral crystals, dark color, and a density over 5, together with a slight magnetic attractability. In examining with the microscope many products of mechanical muffle-roasting kilns, it is, however, impossible to find individual grains which can be identified as consisting entirely of zinc ferrite. The variety of colors, especially where each grain of blende was mechanically free from marcasite, rather conveys the impression of a partial ferritization of the grain. One side or end, for example, may often have the hard, dense surface and dark red to black color of the ferrite, while the balance shows the usual light yellowish brown of a normal iron-free blende.

Jan 1, 1914

By E. T. Dumble

In the Bosquejo Geoldgico de Mexico, published in 1897 by the Secretaria de Fomento as Nos. 4, 5 and 6 of the Boletin del Institute Geologico de Mexico, the Director, Jose C. Aguilera, after a detailed account of the geological observations made by himself and his assistants on their several trips through the various districts of the Republic, gives in Part 2 a synopsis of the geology of Mexico, describing . al1 the formations recognized, the rocks comprised in them, their geographical distribution, disturbances, principal eruptions and economic features, as explanatory of the Geological Map of Mexico. In Part 3 Prof. Ordonez describes many of the interesting eruptive rocks of Mexico." This work brings together in a very satisfactory way about all of the published results of geological investigations in Mexico; and although the determinations of the authors with reference to some of the sedimentary deposits are very different from those of other writers, they seem to be based upon good paleontological grounds in each instance. From the map and the text of this paper it appears that the condition of knowledge in regard to the geology of the State of Sonora, at the time of its publication, was about as follows: The western portion of the State, lying between the coast line of the Gulf of California and the foot-hills of the Sierra Madre mountains, is largely Quaternary, interrupted by areas of Azoic rocks and of later eruptives, with two or three limited exposures of limestones of the Cretaceous; while the eastern or

Jan 1, 1900

By A. E. Bellis, T. W. Hardy

The problem of heat treating high-speed steel becomes more and more important as the design of cutters becomes more and more complicated in increasing the efficiency of mechanical operatioqs. Hundreds of dollars are spent in the design and manufacture of milling cutters of special form for rapid production of duplicate or interchangeable parts, and then, as the heat treatment is faulty on the one hand, or scientifically executed on the other, the tool fails after a few operations, or its efficiency is greatly increased. The practical operation of giving these complicated tools the right temperature necessary to bring out the best cutting qualities, and at the same time bring-the tool out "clean," is a difficult one and calls for no small amount of skill. In order to be on the safe side the average tool hardener uses a temperature much too low to give the best results with the high-speed steel he uses. In the case of cutters which are finished to a given diameter before hardening, it is impossible to grind the tool after hardening, so that it is essential that the surface be protected from oxidizing or de-carbonizing. It is the aim of this paper to describe some experiments on hardening high-speed stee1, in which metallographic means were used to determine the correct hardening tempcratures. The accompanying table and plates show the results of hardening experiments on five different high-speed steels. The analyses for carbon, tungsten, chromium and vanadium of each steel are given in the accom- . panying table. Six specimens from the same bar of each kind of steel

Jan 1, 1917

By A. L. Holley

There is a growing demand for pure and cheap material for fine open-hearth steel; a material not only very free from phosphorus, but from carbon and silicon; so that it may he rapidly converted into steel. Iron and steel scrap are not trustworthy as to quality, and they are often dear. There are three methods of purifying cheap materials for the open hearth. 1. Mechanical puddling, as done at Creusot, which removes 90' per cent. of the phosphorus from the pig iron. 2. Krupp's washing process (the conduct and results of which 1 fully described in a former paper*), which eliminates 70 to 80 per cent. of the phosphorus and most of the sulphur and silicon from pig iron. Neither of these processes would sufficiently purify, for very fine steel, those very impure pigs which are cheapest in many parts of the United States. 3. The process of producing directly from the ore an iron which is practically pure chemically, although mechanically mixed with the impurities of the ore. This is the oldest of iron processes ; one form of it, the CataIan forge, employed to produce charcoal blooms, is still in use, but its great cost is rapidly throwing it out of competition. Among the modern attempts to produce iron direct from the one, on a large scale and at a cheap rate, several have been in various respects successful. Dr. Siemens's process of treating a ton and a half or more of ore and the coal to deoxidize it, in a rotating gas furnace, and bringing out, in some four hours, a ball of chemically pure iron so soft that the fluid and impure slag may be sqneezed out of it, is the most attractive and the most highly developed of all the modern direct processes. I hare watched it, from time to time, since 1874, and have noted a steady improvement. It may now be said to have passed the experimental stage, although, like older processes, it must be adapted by practice to special materials. The cause which has been more potent than all others, including the defects of the best direct processes, to bring these processes into disrepute, is the wasteful treatment of the direct product. With one or two exceptions (when failure mas due to other and obvious causes), the direct product has been made into wrought iron (weld iron). Even Dr. Siemens has, at Towcester, in England, and at Park, Bro. & Co.'s, in Pittsburg, set up his apparatus for this purpose. Is it likely that

Jan 1, 1880

By Robert H. Chapman

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

Jan 1, 1900

By C. F. Tolman

In February 1913, Prof. L. C. Graton and Dr. Joseph Murdochl presented to the American Institute of Mining Engineers a notable contribution to economic geology under the title The Sulphide Ores of Copper. The value of the work was recognized by mine operators, and Mr. Graton was assisted in his plan to extend his investigations, by the organization of a commission to undertake a "secondary enrichment investigation." In this work he secured the cooperation of the Geophysical Laboratory of the Carnegie Institution of Washington. The report2 on the chemical phascs of the investigation has just been published. Incidental to investigations3 carried on in our laboratory of Economic

Jan 1, 1916

By William A. Prichard

After a study of the excellent geological reports and maps prepared by the United States Geological Survey,? and after practical experience in working the ore-deposits in this field,

Jan 1, 1904

By E. H. Dix

All commercial aluminum contains small percentages of copper, iron, and silicon as unavoidable impurities. The purest metal obtainable commercially, special grade high purity ingot, contains a maximum of 0.50 per cent. impurities of which the usual minimum amount of copper is 0.01 per cent.; silicon, 0.12 per cent.; and iron, 0.20 per cent. This grade is too costly for most purposes. The two standard grades, Nos. 1 and 2, containing a minimum of 99.0 and 98.0 per cent. aluminum, respectively, are more generally used. Other grades of secondary aluminum often contain as high as 3 or 4 per cent. of impurities, which include 1 per cent., or more, of zinc. Specifications for high-grade aluminum-casting alloys generally allow a maximum of 1.7 per cent. for total impurities. The S. A. E. Specification No. 33, which is intended to cover alloys made from secondary aluminum ingot, gives the iron maximum as 1.5 per cent. and the maximum for silicon (including manganese and tin) as 0.75 per cent. The effect of even relatively small amounts of impurities on the physical properties of ingot aluminum is shown by the following cornparison of two lots of aluminum, which may be taken as representative of special grade and grade No. 2 ingot, respectively. AnalysEs Special Grade, Gbade No. 2, Per Cent. PeR CBnt. Copper................................. 0.01 0.32 Silicon................................. 0.12 0.32 Iron................................... 0.42 0.82 Aluminum.............................. 99.45 98.54

Jan 1, 1923

By E. H. Dix

All commercial aluminum contains small percentages of copper, iron, and silicon as unavoidable impurities. The purest metal obtainable commercially, special grade high purity ingot, contains a maximum of 0.50 per cent. impurities of which the usual minimum amount of copper is 0.01 per cent.; silicon, 0.12 per cent.; and iron, 0.20 per cent. This grade is too costly for most purposes. The two standard grades, Nos. 1 and 2, containing a minimum of 99.0 and 98.0 per cent. aluminum, respectively, are more generally used. Other grades of secondary aluminum often contain as high as 3 or 4 per cent. of impurities, which include 1 per cent., or more, of zinc. Specifications for high-grade aluminum-casting alloys generally allow a maximum of 1.7 per cent. for total impurities. The S. A. E. Specification No. 33, which is intended to cover alloys made from secondary aluminum ingot, gives the iron maximum as 1.5 per cent. and the maximum for silicon (including manganese and tin) as 0.75 per cent. The effect of even relatively small amounts of impurities on the physical properties of ingot aluminum is shown by the following cornparison of two lots of aluminum, which may be taken as representative of special grade and grade No. 2 ingot, respectively. AnalysEs Special Grade, Gbade No. 2, Per Cent. PeR CBnt. Copper................................. 0.01 0.32 Silicon................................. 0.12 0.32 Iron................................... 0.42 0.82 Aluminum.............................. 99.45 98.54

Jan 1, 1923

By Victor Lenher

The interest shown recently in selenium and tellurium has brought many requests for an assembling of the analytical chemistry of these two elements. The intention of this paper is to discuss all of the chemical principles utilized in the detection and quantitative determination of these elements, as well as to describe the works methods actually followed by producers of tellurium and selenium in the United States. These methods have been furnished by S. Skowronski of the Raritan Copper Works, H. D. Greenwood of the United States Metals Refining Co., F. F. Colcord of the U. S. S. Lead Refinery, and E. W. Rouse and A. E. Hall of the American Smelting and Refining Company. Occurrence Selenium is found associated with sulfur, to which in many respects it is quite similar. Occasionally deposits of native sulfur, notably those in the Lipari Islands, Kilauea, and Japan, show a red-brown coloration, I which is readily distinguished from that of other sulfur; this red-brown * sulfur contains a small amount of selenium. Not infrequently, the , sulfides of the heavy metals are accompanied by selenium and tellurium, • presumably as selenides and tellurides. The Scandinavian pyrite, which is one of the large sources of European sulfuric acid, when roasted has fur- - nished a large part of the selenium that has come to the United States; it I was in flue dust from the roasting of Scandinavian pyrites that the element was discovered by Berzelius in 1817. Greek and Spanish pyrites also

Jan 1, 1923

By Victor Lenher

The interest shown recently in selenium and tellurium has brought many requests for an assembling of the analytical chemistry of these two elements. The intention of this paper is to discuss all of the chemical principles utilized in the detection and quantitative determination of these elements, as well as to describe the works methods actually followed by producers of tellurium and selenium in the United States. These methods have been furnished by S. Skowronski of the Raritan Copper Works, H. D. Greenwood of the United States Metals Refining Co., F. F. Colcord of the U. S. S. Lead Refinery, and E. W. Rouse and A. E. Hall of the American Smelting and Refining Company. Occurrence Selenium is found associated with sulfur, to which in many respects it is quite similar. Occasionally deposits of native sulfur, notably those in the Lipari Islands, Kilauea, and Japan, show a red-brown coloration, I which is readily distinguished from that of other sulfur; this red-brown * sulfur contains a small amount of selenium. Not infrequently, the , sulfides of the heavy metals are accompanied by selenium and tellurium, • presumably as selenides and tellurides. The Scandinavian pyrite, which is one of the large sources of European sulfuric acid, when roasted has fur- - nished a large part of the selenium that has come to the United States; it I was in flue dust from the roasting of Scandinavian pyrites that the element was discovered by Berzelius in 1817. Greek and Spanish pyrites also

Jan 1, 1923