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Discussion, at the Virginia Beach Meeting, February, 1894, of the Paper of Prof. Posepny. (Trans., xxiii., 197, 587.) Including communications subsequently received. a T. A. Rickard, Denver, Colorado (communication to the Secretary) : The paper of Professor Posepny was printed so short a time

Jan 1, 1895

By J. F. Kemp

The use of nickel-steel has directed increasing interest of late towards the deposits of nickel, and at the same time the parallel advance in our knowledge of the basic igneous rocks has rendered these deposits a subject of important geological inquiry. Investigations have led to some views, more or less new, on the igneous origin of certain ores, which, though not universally accepted, have a growing number of adherents. In Europe, the mines in Norway have been especially suggestive subjects of study, and others somewhat less generally known have also added their testimony; while in this country the great economic importance and scientific interest of the developments in the Sudbury district of Canada, have furnished the principal texts for the discourses that have appeared among us. The purpose of the present paper is to set forth these views through the medium of one interesting ore-body, of which but little has been written ; and, by the description of another, to place in contrast two different geological associations in which nickeliferous pyrrhotite occurs, and to indicate a generalization, based upon these different geological characters, and justified by the experience so far gained. To Prof. J. H. L. Vogt, of Christiania, Norway, is due the chief credit for the revival of interest in the geology of nickel. His important contributions* of recent date have made generally available

Jan 1, 1895

By H. H. Campbell

The following paper deals almost exclusively with the results of practice at the works of the Pennsylvania Steel Company at Steelton, Pa. From the records of the furnaces at this plant, both acid and basic, large and small, are drawn the data for the various demon strations, and on a long and intimate experience with their opera tions are founded many theories and generalizations. It may seem that universal laws should not be built upon a basis so restricted ; but in reality the condition is the strongest guarantee of validity. Each table investigates some- certain variable, and by virtue of the common origin of the factors, we have good ground for assuming the corresponding agents to be equal. The examples may or may not be instances of good practice, and may be open to criticism if regarded solely as exponents of • metallurgical success. But it must be remembered that the lists are not made up of selected specimens, nor are they chosen to show su perior results; they are gathered to investigate, by strict scientific methods, the formula? of the operation. In such work no untoward results should be eliminated, save those which bear upon their face the stamp of experimental error. If the worst members be omitted, then the best must also be omitted. Only by using every available case can an honest attempt be made to deduce a true average. It is recog nized, however, that with the most careful selection it is difficult, if not impossible, to collect data representing universal conditions. In each table the records tell of a special practice, and all conclusions drawn from them are true only within the limits between which the equations have been integrated. Not assuming the prerogative of speaking for American melters in all the opinions herein expressed, nor acting as a camera in por traying an ephemeral state of national metallurgical development,

Jan 1, 1894

William H. BLAUVELT, Anaconda, Mont.: Mr. Stetefeldt's comparison of the producer-plants at Aspen, Colorado, and Park City, Utah, is of special interest at this time, when the attention of all western metallurgists is so forcibly drawn to the necessity of reducing expenses and losses. The fact that wood was used at Park City before gas was introduced, for firing the Stetefeldt furnace and dryer, offered an excellent opportunity for showing the economies resulting from the adoption of gas in place of wood, as well as a comparison between the two gas-plants. Some time ago Mr. Stetefeldt contributed an article to one of the technical journals, in which the economy obtained by the substitution of gas for wood at this plant was shown quite in detail. I regret not being able to quote from his article at length, but, remember that the total saving effected would pay for the producer-plant in about one month. This is a striking instance of the advantages to be secured by the adoption of the best methods of using fuel in our metallurgical works. In comparing the figures from the Park City and Aspen plants, the difference of over 20 per cent. in the fuel used in the Stetefeldt furnaces, seems remarkable, even considering the larger amount of sulphur in the Aspen ore, and the greater rapidity with which it was roasted. It would be interesting to have Mr. Stetefeldt's, opinion as to the cause of so great a difference. The inferior economy of the revolving dryers at Park City might be overcome by lengthening them, or so arranging a second one above

Jan 1, 1894

By G. Chesneau

Two great discoveries of this century have diminished the dangers of fiery coal-mines,—the sifety-lamp, conceived in 1815 by Sir Humphrey Davy and successively improved by many engineers, such as Clanny, Marsaut, Mueseler, Fumat, etc., and safety-explosives, the appearance of which is comparatively recent, hut which, thanks to the persevering labors of several technical commissions (especially the French commission on explosives), and of the manufacturers and experimental users of these powders, appear likely to play, in the protection of the miner, a part as important as that of the safetylamp itself. Brit while it is true that by the use of a safety-lamp of approved form, and the exclusive employment, with all prescribed precautions, of these new explosives, complete security should be assured, even in highly fiery atmospheres, experience has shown that the imprudence of workmen, or the bad condition of a lamp, may nullify these protective means, so that it ought to be the constant care of the engineers of fiery mines to dilute the fire-damp by good ventilation so far as to maintain always and in all parts of a mine a proportion of this gas below the lower limit of explosiveness belonging to a mixture of air and methane. Good ventilation still remains the best preventive of explosions from fire-damp, and since, even with a rational and well-controlled mine-ventilation, the volumes of air traversing galleries and rooms are liable to vary within wide limits by reason of open doors, falls of rock, or other accidental causes, it follows that but a few thousandths of fire-damp should be left in the normal atmosphere of the mine-workings, so that a considerable

Jan 1, 1894

George IV. Goetz, Milwaukee, Wis.: Mr. Campbell deserves much credit for his interesting paper. The literature of the development of the open-hearth process is distributed in many technical journals, and is difficult of access to many engineers. Since the development of the basic process, the open-hearth furnace has been raised from a subsidiary to an independent position. Certain high grades of soft steel can be produced in the basic open-hearth furnace, which cannot be produced by any other known process. In the United States the charges for the acid process generally consist of either scrap and pig-iron or so-called wash-metal and scrap : the pig-and-ore process, as carried out in England, is practiced but very little. The introduction of the basic process has made it possible to use about four times as much pig-iron with scrap as can be used in the acid mixtures. The availability of a cheap pig-iron, very low in silicon and sulphur, and carrying several per cent. of manganese, is one of the reasons why the basic open-hearth process has developed so rapidly in Germany, as regards the output per furnace and the excellent quality of the material produced. The acid Bessemer steel has an inherent stiffness, which is plainly shown when spring steel is made by the Bessemer and by the openhearth processes. In order to get them of about equal stiffness, the open-hearth steel must have about 0.60 per cent. carbon ; whereas, the Bessemer steel must then have ahout 0.45 carbon, the remaining constituents being apparently about the same in each product. It has proved impracticable, with American coke-pig-iron, to interrupt blowing at a certain point in order to make hard steel; and experience has therefore shown that it is best to eliminate nearly all the carbon, and then to recarburize to the desired point. This practice

Jan 1, 1894

By E. C. Potter

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

Jan 1, 1894

By James Gayley

The lining of the hearth and bosh of a blast-furnace has naturally come to be considered its weakest part, being subject not only to abrasion, but also to intense chemical action. In order to provide against rapidity of wear, it was formerly customary to build the lining from the mantle to the top first, and to put in afterwards the hearth and bosh, drawing the latter into a recess that had been reserved for it in the upper lining. At some works this practice still prevails ; but through the progressive development of cooling-devices, it has become possible to protect the bosh so well as to make it the most durable part of the furnace. The main question now is, by which one out of several methods the best economy results can be obtained. The plain bosh-jacket, made of wrought-iron or steel, and frequently called the air-cooled jacket, was a great improvement over the crinoline-construction formerly in vogue; but it was difficult in many cases to persuade furnace-managers, that in order to secure its best effects, they must discard the thick bosh-walls and put in comparatively thin ones. Mr John M. Hartman, who did more perhaps than any one to extend the use of these jackets, invariably contended for a 13-inch wall, the thin wall being an essential part of this construction. Later, a coil of pipe was placed just inside the jacket, through which water, circulating freely, contributed further to the proper maintenance of the walls. Undoubtedly much better results have been obtained in practice where the iron jacket has been supplemented by a coil in this way. It is safe to say that this combination of water-coil and jacket is much better than external sprays on the jacket; but it does not prevent the brick-work from cutting entirely away, which enlarges the bosh to that extent and interferes with the economy and output of the furnace. In case of leakage or stopping-up of the pipes, they cannot be replaced. A leading blast-furnace manager who is now using this construction

Jan 1, 1893

By Walter B. M. Davidson

Phosphorus is one of the elements having the widest distribu tion, and phosphoric acid plays an important part in the composition of the crust of the earth. It is allied in various chemical combina- tions with many bases, of which lime, alumina and iron are the most common. It is difficult to state in what chemical combination phosphoric acid predominates in the crust of the earth, for while phosphate of lime, as the mineral which is sought for and found in deposits of economic value is the most familiar, it is probable that the phosphates of alumina and iron are the most usual forms in which phosphoric acid exists in all soils not essentially calcareous. It has been shown by thousands of analyses that all fertile soils contain from a trace to 0.5 per cent. of phosphoric acid. All limestones, dolomites and chalks contain it in proportions which, though usually small, are large enough to make careful analysis necessary in the selection of limestone as flux for iron-smelting. It is generally Trenton limestones that are found best for this purpose, the more recent strata being more phosphatic. In some places phosphoric acid replaces carbonic acid, and the limestone or chalk becomes phos phatic to a large degree, or sometimes pure phosphate of lime. The waters of the ocean, from very early periods, have contained phosphoric acid. Different analyses show varying contents; it is asserted that some portions of the Gulf Stream are more phos phatic than the surrounding waters of the Atlantic. Many springs, usually from limestone regions, contain soluble phosphates in vary ing quantities. I think it safe to assert that phosphorus is nearly the most widely and evenly distributed element on the surface of the earth, and probably the most subdivided. This can be readily understood when the important part which phosphoric acid plays and has played in the vital cosmos is taken into consideration. Phosphorus was on the earth in gaseous, liquid or solid form before the dawn of life, and since then all animal and vegetable creation have combined with the

Jan 1, 1893

By W. H. Morris

I have been requested to present a paper on the slag from the basic Bessemer process, as prepared for fertilizing. Since Professor W. B. Phillips presented at the Birmingham meeting, in May, 1888, an able paper* on this subject, as it had been developed up to that time, there is little for me to add. Perhaps later practice may be best expressed by the homely proverb, " The proof of the pudding is in the eating." As the Pottstown Iron Company is the only concern manufacturing basic Bessemer slag in this country, the writer's personal experience in the use of it may be interesting. Our slag averages: P2O5, 21.37; SiO2,, 5.10; MgO, 5.90; Al2O3, 4.01; MnO, 5.56 ; FeO, 12.00; Na2O and K2O, 0.80; CaO, 45.26; total, 100.00. This gives over 76 per cent. of phosphoric acid and lime. In using this material for several years past on my lawn and garden, I have found it better than anything else I have ever tried ; and I am sure that any of you who had seen my green grass last month (January), wherever the ground was bare from snow, as bright as in early fall, would be forced to acknowledge the advantages of this soil-enricher. The grass on my private lawn, and around the company's office, is green the whole winter; and we have raised very good sod, by the use of this phosphate, where, without it, we were unable to get the grass to grow either from seed or by repeatedly sodding. The same statement applies to garden-truck; when the soil was first broken up, a good crop of vegetables was easily raised. My own gardener has had several premiums from Philadelphia seedsmen (notably, last year, the first premium for sugarcorn raised in the first part of July, being the first sample sent them). Our method of applying this material is to grind the slag very finely, so that at least 60 per cent. of it will go through a 150-mesh screen (i.e., say, 22,500 meshes to the square inch), and 90 per cent. through a 100-mesh screen (i.e., 10,000 meshes to the square inch). This fine grinding seems to be the main condition of success.

Jan 1, 1893

By W. C. Coffin

Fire-brick stoves have become a necessary part of the modern coke blast-furnace equipment, and are also superseding the cast-iron pipe stoves in anthracite- and charcoal-furnaces. The brick stoves in general use are of either the Cowper or Whitwell type, or modifications of these bearing the names of those who invented the alterations from the original types rather than any real departure from then]. All these stoves have approximately the same valve-equipment and follow the same line of operation. The waste gas from the furnace enters at one port and burns in a single combustion-chamber, and the heated products are drawn through the various passe; in the brickwork to a stack of proper height to create the necessary draught. The last passes of these stoves receive a very small percentage of the heat from the gas, owing to their extreme distance from the combustion-chamber; and this chamber also suffers great deterioration in the attempt to force the heat into the farthest passes. At best, about 70 per cent. of the heat taken up is held in the combustion-chamher and the first down-pass of the Whitwell stoves. Mr. Hugh Kennedy, Manager of the Isabella Furnaces, Pittsburgh, Pa., who has had a large experience with the fire-brick hotblast stoves, was so strongly impressed with the fact that but about thirty per cent of the brick of the average stove were doing proper duty as heat-agents, that, after careful study and experiment, he had three 20- by 60-feet stoves constructed with a view of more uniformly heating all the brick. In these the general lines of the Whitwell stove are followed, with the blast-connections unaltered, but gas is introduced at the bottom of each pass, and outlets are provided at the top, so that the gases have a direct natural draught in each pass and the highest heats are obtained at the bottom instead of the top. The natural tendency being toward the reverse condition, the brickwork soon acquires an almost uniform temperature.

Jan 1, 1893

By Joseph Hartshorne

This plant is situated in the borough of Pottstown, on the banks of the Schuylkill river, between the Philadelphia and Reading Railroad and the Schuylkill Division of the Pennsylvania Railroad, on a plot of about 125 acres, most of which is reserved for future extensions. About 45 acres are to be used for houses, 40 of which have already been built. The accompanying plan will give a clear idea of the general arrangement of the works. Beginning at the lower or eastern end, the first building is the basic-cinder grinding-plant. At present, it consists of a 2000 mm. Jenisch ball-mill (Kugelfallmühle) similar to those used so extensively for grinding basic cinder in Europe. It was built by Herman LÖhnert, of Bromberg. The mill is very simple in design, and efficient in execution. About 13 horse-power is required to run it, and the average output is 20,000 pounds in 10 hours. The best work we have done is 29,000 pounds in 10 hours, with perfectly dry cinder. From 95 to 98 per cent. of the product will pass through a sieve with 100 meshes to the inch, while from 70 to 75 per cent. will pass through a 150-mesh sieve. The mill has been in service since last March, part of the time on double-turn, and the renewals and repairs have been very slight. The product of the plant is sold as a fertilizer. It runs from 18 to 24 per cent. in phosphoric acid, about 14 of which is reverted. The merits of this fertilizer were explained by Mr. W. H. Morris, at the Baltimore meeting of February, 1892 (Trans., xxi., 232), and by Mr. W. B. Phillips, at the Birmingham meeting of 1888 (Trans., xvii., 84). The results obtained by its use in Europe, where over 600,000 tons were used last year, are well known. Near the cinder-grinding plant will be situated the new machineshop, which is now being erected. The next buildings contain the brick-making plant and ovens.

Jan 1, 1893

By Axel Sahlin

Having no business interest in any of the various machines used for granulating ores, my remarks on the subject are prompted solely by my desire to contribute towards the determination of the best apparatus such information, as I have been able to gather,

Jan 1, 1893

Jan 1, 1893

Marius R. Campbell, Washington, D. C. (Communication to the Secretary): Having spent considerable time in a systematic study of this field,'both as regards the details of its structure and stratigraphy and the broader question of its relation to the Appalachian basin, I wish to add a word concerning the correlations made by Mr. Hodge in his paper. From A commercial standpoint, the question of correlation, even along the strike, is of little or no importance, for the variability is such that each opening should be tested individually, regardless of the horizon at which it appears; but these correlations assume an entirely different aspect when their scientific bearing is considered; they then become of vital importance, and, before being accepted, should be subjected to the most rigid scrutiny and severe tests. Mr. Hedge states positively that the Imboden seam of coal is equivalent to the Elkhorn coal of Pike and Letcher counties, Kentucky. In the writer's opinion, such equivalency is, at the utmost, only a possibility. This correlation has been generally adopted by the geologists of the Kentucky Geological Survey, but the writer has been unable to find on what grounds they base the statement. The evidence of identity seems to be in the character of the coal, as both seams furnish fine coking coal; also, in the similarity of the interval between them aid the " Bee Rock," or top of the great conglomerate. It is probably an easy matter to determine the thickness of this interval on Elkhorn creek, and we will assume that the measure of 300 to 350 feet is correct. In the Big Stone Gap field, the question of measuring the interval between the Imboden and the " Bee Rock " is exceedingly difficult. The line of outcrop of this mass of strata is along the northern base of Stone mountain, and, in the uprising of the great arch, the strata on its flanks have been thrown into many minor folds, and, in places, have been broken by local faults. This complicated structure, together with the absence of ally well-marked stratum, renders it exceedingly difficult to obtain a correct measure of the intervening sandstones and shales. The interval of 300 to 350 feet, assigned by Mr. Hodge, is mani-

Jan 1, 1893

By C. A. Stetefeldt

Jan 1, 1892

By H. L. Bridgman

The correct sampling of ores is a subject of far greater importance than is usually conceded to it. Of the little which has been published on this subject, the recent paper by Mr. Glenn, with the accompanying discussion by Dr. Raymond (Trans., xx., 155), is the latest and best, and well worthy the careful perusal of all interested in accurate sampling, whether by hand or by machine. It is doubtless true that thorough hand-sampling gives as good average results as can be obtained; but all hand-sampling is subject to the possible incompetency, carelessness, or dishonesty of the workmen employed. It is, moreover, tedious and expensive, requires large space, and usually entails considerable delay, both in unloading and in sampling. For these and other reasons, machine-sampling is now regarded with more favor than ever before. So-called machine-sampling may be accomplished in two radically different ways: 1. Part of the stream of material is taken for the whole time. 2. The whole stream of material is taken for part of the time. Under the first case the stream, as it issrles from the deliveryspout of the crusher, is cut continuously in any given proportion, such as one-tenth, one-fourth, or one-half, by some fixed apparatus, which, as it contains no moving parts, is strictly speaking not a machine at all, but may be termed an appliance. The principle under which these appliances operate is now pretty generally conceded to be wrong, becanse of the practical impossibility of' cutting such a

Jan 1, 1892

By H. H. Stoek

Danville, the county seat of Montour county, Pa., was one of the earliest and best-known centers of the iron intlustry in the State. It is situated on the north bank of the north branch of the Sosquehanna river, twelve miles east of the confluence of the north and west branches of that river at Northurnberlttnd. The ore-belt, extending for a distance of twelve miles along the north bank, has been developed in a number of places, but nowhere so extensively as in the immediate vicinity of Danville. Hence, a description of the mines in that locality will suffice, as typical of the workings of the entire section. Geology. The Montour ridge consists of an anticlinal fold extending from the source of Wapwollopen creek on the east to the west branch of the Susquehanna, which it reaches at the mouth of Chilisquaque creek. According to the reports of the First Geological Survey of Pennsylvania, the length of the ridge is nearly twenty-seven miles, with an average breadth of three-fourths of a mile, and a maximum elevation of six hundred feet in the vicinity of Danville, where it also attains its greatest width. Just north of Danville the Mahoning creek cuts through it, exposing the iron-ore on the hill-side, where advantage has been taken of this to work the beds on the southern slope of the ridge by means of drifts. The sections given in Fig. 1 are taken from the reports of the First Geological Survey of Pennsylvania, made in 1858, by H. D Rogers, whose description of the Moatour ridge was so complete and accurate that the entire report was reprinted as an appendix to Vol. G 7 of the Second Geological Survey. The approximate crosssection shows that near Danville the top of the ridge is of Clinton vol, xx.—24

Jan 1, 1892

By Rufus J. Foster

During the discussion on the Preparation and Utilization of Sniall Sizes of Anthracite (page 613 of present volume), several inquiries were made concerning the use of the McClave grate, which was mentioned by Mr. Coxe as having proved satisfactory in the generation of steam at his collieries, and also at a large number of industrial estal)lishments in Scranton and elsewhere. For a more satisfactory repIy to such inquiries than could be furnished in the oral discussion, I have prepared the following paper to be included in the published proceedings. And, as the use of the fuel under consideration necessarily requires the employment of a blower to change the fire, from a condition giving an incandescent radiant heat only to one giving a hot gaseoua flame as well, I shall add a description of the McClave Argand blower and its method of action. The grate and blower combined form a complete and effective system fcr burning small fuels, such as anthracite culm, birdseye, buckwheat, bituminous slack, etc., in boiler and other furnaces; while the grate alone is now extensively used with the larger sizes of hard and soft coal in furnaces where blast is riot required. Fig. 1 is a view of the RlcClave grate as built in two sections. It is constructed on the principle best approved by practice to prevent warping and burning out; that is, it presents no long lines of

Jan 1, 1892

By James Gayley

The development of blast-furnace practice in America in the direction of large yields is mainly the history of our working since the year 1880, as the advancement that has been made in the last decade is greater than that in the third of a century previous. A new era in the manufactnre of pig-iron began in 1880 with the putting in blast of the Edgar Thomson furnaces. These furnaces at once leaped to the front as pig-iron producers, and have maintained that position—with but one brief interruption—ever since. I shall, therefore, confine myself mainly to a description of these works, showing the changes in design and practice by which these results have been achieved. In order to show more clearly the progress that has been made since 1880, I shall refer briefly to the best work that was done in the ten years previous to that time. The Struthers furnace, in Ohio, was one of the first to attract attention in the matter of large outputs. This furnace was 55 feet high, 16 feet in diameter of bosh, 9 feet in the hearth, and about 8 feet 6 inches at the stock-line. The fuel was raw coal. This furnace, in December, 1871, made 1602

Jan 1, 1891