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By F. Lynwood Garrison

There is probably no subject for study in the metallurgy of iron and steel of greater interest than the effect of manganese upon the properties of iron. Some of the peculiarities of iron and steel containing appreciable quantities of manganese were observed many years ago by Heath, Robert Mushet, and others; but it was not until the introduction of the Bessemer process, when a demand was created for large quantities of iron-manganese alloys, that such compounds of iron and manganese became articles of commerce. Since that time the demand for these alloys has steadily increased, the use of ferro-manganese not only becoming an absolute necessity in the ordinary Bessemer practice, but also essential to the manufacture of open-hearth, crucible steel and steel castings; in fact it is the only source of supply for all the manganese used in metallurgical opera-

Jan 1, 1893

By Francis Freeland

An examination of accessible English literature shows that but small space has been allotted to the determination of faults ; most suggestions being confined to Schmidt's rule of the downthrow on the hanging-wall of the fault, or the coal-miner's rule of the obtuse angle. Von Carnall's modification of Schmidt's rule is sometimes given without the important exception, and Zimmermann's rule is

Jan 1, 1893

Jan 1, 1893

By D. H. Bacon

Our Transactions contain so many suggestions of apparently trivial, yet really important, contrivances for the saving of time and

Jan 1, 1893

By F. H. McDowell

The increasing interest in the subject of electrical separation warrants the addition to what has already been written of a few lines covering the practical workings of the Tilly Foster mill under the direction of Mr. E. S. Moffat, General Manager. Since my last paper was presented to the Institute, Mr. S. P. Tomkins, the superintendent, has had thrust upon him for solution several problems complicated by the introduction of new conditions. 1. The richer portion of the lean ore dump, and that nearest the railroad track, having been worked up in 1890, the handling of the balance, including a largely increased amount of rock, could only be accomplished at an increased cost. 2. The tailings had accumulated close about the mill to such an extent that arrangements had to be perfected to move them further away.

Jan 1, 1893

By William H. Morris

At the Glen Summit meeting, the question of controlling the silicon in pig-iron WAS raised; and as this has been deemed by most furnace-men for years past a matter of special difficulty, an account of our experience in the matter may be of interest. When running on mill-iron, some years ago, we aimed to keep

Jan 1, 1893

By Fred W. Gordon

Apart from the character of pig-iron to be manufactured, other than that it shall be well reduced and open-grained, the selection of the materials should be such as to produce it at the lowest cost. As a rule, the sources of fuels and limestones are not so extensively varied as those of the ores. Many Eastern furnaces are now using Lake Superior ores, and but recently a part of the supply came from foreign ports. It is, however, of the highest importance that the character of fuels and limestones, as well as ores, should be carefully considered in determining their value and making judicious selection among those available. The formulas here offered are based upon the assumption that the heat-requirements for a given mixture are measured by a constant required by the oxide of iron, added to that required for a unit of slag, multiplied by the weight of that slag per unit of iron. The heat-requirements for oxide of iron per unit of pig-iron made are assumed to be 2854 centigrade units. This is taken from the careful analysis of Sir Lowthian Bell, and, so far as the writer is able to determine, is very nearly correct. Dividing this by the quantity of heat that may be evolved and utilized within the furnace per unit of carbon, determines the quantity of carbon required per unit of pigiron ; and if to this be added the quantity of carbon absorbed by the pig-iron, the total requirements in carbon are determined, on the assumption that pure oxide of iron is reduced with pure carbon by the ordinary process of the blast-furnace. Calculating the quantity of slag that would be made from a given mixture of ores, smelted with a given impure fuel and fluxed with a given impure limestone, multiplying this weight of slag by the heat-requirements of its unit (taken at 1050 C. H. U.), and dividing the product by the heat-units evolved and utilized within the furnace per unit of carbon, will determine the quantity of carbon required per unit of pig-iron for the slag.

Jan 1, 1893

By Carl Henrich

Jan 1, 1893

[Note.—The paper of Mr. Hoffman on " Practical Results in the Magnetic Concentration of Iron-Ore " (page 602); that of Mr. Langdon on "The Use of Magnetic Concentrates in the Port Henry Blast-Furnaaces" (page 599); and those of Mr. Landis on "The Determination of Iron in the Tails from Magnetic Concentration " (page 609) and "Note on Sampling Iron-Ore" (page 611), were all prepared as contributions to this discussion.] The papers of Mr. Langdon and Mr. Hoffman were presented. W. H. Hoffman, Croton Mines, N. Y.: I will add a few remarks, by way of answer to inquiries for further details. The Croton Mines are particularly well located for cheap mining. The ore-bed is very large, and so lies in relation to the railway tracks of the Harlem and other railroads that a very large proportion of our mining for several years to come can be done above these tracks. The concentrating-mill is now 400 feet from where we are working in the quarry. In blasting we never remove less than 2500 tons at a blast,

Jan 1, 1892

By Charles M. Rolker

The main tin-producing regions of the world are known to be England, Australia and the Dutch East Indian possessions, chiefly Banca and Billiton. During recent years, the tin of the Malay Peninsula, exported from Penang and Singapore, has been coming prominently to the front. France, Austria, Hungary, Germany, Spain, South America, Russia and China still present insignificant figures. The conspicuous part which the Dutch possessions in the Indian Archipelago have taken in supplying the world with tin, is well known. Tin was discovered in Banca as early as 1710, and has been produced there ever since; but the supply has been most important since Banca came fully into the possession of Holland, in 1821. In Billiton and the adjoining island of Singkep, the existence of tin was known prior to 1822.* The Lingganese knew of its existence in the valley of Embalong, from creeks and streams in the neighborhood of Tima and Simper hills, on Billiton and also on Singkep island, but the prevailing superstition that tin-mining brought misfortune, influenced them to let this industry lie idle. The attempts of the Dutch government to test this question were lukewarm, perhaps by reason of the fear of reducing, through new discoveries, the price of Banca tin, and the island was abandoned in 1826, leaving only a military post. In 1850, Dr. Crookewit, a chemist and naturalist, was sent out to verify the rumors that tin existed in Billiton. His report was unfavorable; but in 1851 Mr. C. De Groot, a mining engineer, found tin readily, and the active work on Billiton dates from that time. Less than 600 tons were produced during the first ten years, and 3000 tons in the next decade. Billiton tin-mining is done by

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 John C. Smock

The rich deposits of magnetic iron-ore in the Highlands of northern New Jersey attracted the attention of iron-workers at the time of the earliest settlements in that region. The outcrops of the oreshoots at the Dickerson mine, at Mount Hope, and at Hibernia, in Morris county, and at Ringwood, in Passaic count,y, which were doubtless such as would lead to discovery, location and development of nearly all the large iron-mines in that part of the State, appear to have had their beginnings where the ore cropped out on the surface or where it was scarcely concealed by a thin mantle of earth. In the early history of New Jersey iron-mining, the careful explorations and surveys made by the agents of the famous London Com-

Jan 1, 1892

By John Birkinbine

Four meetings of the Institute have been held in the anthracite coal-fields of Pennsylvania, and excursioris into the district, in connection with meetings elsewhere, have familiarized our members with

Jan 1, 1892

Jan 1, 1892

By M. B. Holt

At this time, when electricity in its various applications is attract- ing so much interest, and with such good reason, it has been suggested to me that, as the Aspen Mining and Smelting Company, of Aspen, Pitkin county, Colorado, was the first mining company in America to employ electrical power for hoisting, a record of what has been accomplished by this company would be of interest. Early in the year 1888 the question of power for the development of the ore-horizon lying below the level of the tunnel through which the property is worked, became one of importance. The conditions under which it was proposed to use power were as follows (See Fig. 1): The company's mines lie upon the northwestern slope of a mountain, the ascent of which is at an angle of 28' from the horizon. The ore, consisting of argentiferous galena and other silver-bearing mineral, is found at or near the plane of contact of a superincumbent mass of blue limestone, with an underlying bed of dolomite. This contact plane dips north 30° west, at an angle of 60' with the horizon. A tunnel 1000 feet in length, driven south into the mountain near

Jan 1, 1892

By W. H. Adams

Shortly after becoming one of the van-guard of mine-developers in the State of Virginia, during the year 1883, I called the attention of the Institute to certain deposits of pyrites, which have been largely worked since. In all cases these deposits are covered with iron-ore (limonite), extending 40, 50 or 60 feet from surface to water-level. The several classes of brown iron-ores are found almost continuously along a prominent ridge of mineral-bearing slates, which can be traced from the James river northeasterly to the North Anna, the Rappahannock and the Potomac rivers, crossing the counties of Louisa, Spottsylvania and Stafford. Outcrops are plainly discoverable from end to end of this belt, also, in places, to the right and left of it, and at intervals there are evidences of workings, some of them for known purposes and others of unknown age and meaning. These old workings have an interest aside from the minerals they may contain or may have yielded. I have been engaged during the past five years in the collection of facts concerning them, which might determine definitely the site of those iron-furnaces, placed by tradition within reach of " the towne called Germanna," which were the first ever built in this State or on this continent. The events which led to the establishment of this important industry are sufficiently narrated in a paper written by Mr. R. A. Brock, Secretary of the Virginia Historical Society, and printed in the Proceedings of the National Museum, 1885, page 77, from which I quote the following : " To Virginia, the first of the English settlements in America, belongs the honor of inaugurating within her limits, as a colony, that most important industry, iron manufacture. "The London Company contemplated a variety of manufacturing enterprises from the very beginning of its authority; prominent among them was that of iron. In 1610 Sir Thomas Gates testified before the council of the Company at London, that in Virginia ' there were divers minerals, especially iron-oare,' lying upon the

Jan 1, 1892

By William Glenn

The taking of proper samples of crude ores seems to he less thoroughly understood, or less carefully practiced, than its impor tance requires. We all know how often we encounter the reports of very accurate assays and analyses, the weight of which as evidence wholly depends on the method of obtaining the sample, and is very probably nil, because there has been no proper sampling. Pissages might be cited from technical books, and from current technical literature (all the work of writers whom we delight to honor) to show that even among high scientific authorities there is too little acquaintance with the practical art of the sampler. There is no metallurgical or chemical establishment which does not frequently receive samples truly representing nothing. They consist usually of bits of ore, or what not, selected because they are worse or better than the average of what they are meant to represent. And they are worthless, no matter who made the selection. Where conscious choice is permitted to enter into the operation, a fair sample will not result, unless by a miracle. The work of sampling is often looked upon as within the realm of boys and of pensioners only. At least, though the manual labor be left to subordinates, the principles on which it is conducted and the safeguards with which it is surrounded are not unworthy of the study of experts; and experts should he ready to teach these principles and enforce them in practice. For exact sampling is the indispensable first step towards learning the value of any boxful, carload or shipload of ore. I propose to give a simple account of the method of sampling by hand, such as I have always pursued. There is nothing new about it. So far as I know, it is the immemorial old method, as old at least as Cornish copper-mining. Perhaps my fellow-members in the Institute may suggest improvements in it. If not, it will constitute a record in our Transactions to which laymen and beginners may be referred.

Jan 1, 1892

By J. Pohlig

It is with more than ordinary pleasure that I have complied with the request of the President of the Verein Deutscher Eisenh?tten leute, to read before this meeting and in this country a paper on a system of transport by wire ropeways which, during the past twenty years, has advanced with rapid strides in Europe, and more partic ularly in Germany. America, with its immense network of railways and water communications, should offer peculiarly favorable oppor tunities for the introduction of these ropeways as feeders, more par ticularly in the mining districts, where, as in Europe, a hilly or mountainous region frequently opposes serious obstacles to the em ployment of surface railroads. The importance of the aerial ropeway as a factor in the develop ment of mineral resources deserves the consideration of every mining engineer. As a case in point, the rich iron-ore of the sierra de Bedar in southern Spain, would probably remain untouched to this day but for an aerial ropeway, 15.6 km. (9 3/4 miles) long, which con nects the mines with the shore of the Mediterranean near the town of Garrucha, affording cheap carriage to the nearest shipping point. A railway would have cost about $480,000 (£100,000), but such a heavy outlay would have more than absorbed all prospective profits on the sale of ore. As the aërial ropeway could be built for a little more than one-fourth of that amount, or $124,800 (£26,000), its erection furnished the successful solution of a profitable mining enterprise. This line has been in satisfactory operation for over two yearn; its details will be referred to later. But beside their importance as feeders, ropeways are valuable as a means of conveyance between works and distant warehouses, and between separate buildings in the same works. Their rapidly spreading introduction for such purposes indicates how keenly the necessity of effecting economies is felt under the stress of an everaccentuating competitiop.

Jan 1, 1891

By H. C. Spaulding

The rapid increase, during the last few years, in the number and magnitude of applications of electric power-transmission to commer cial uses in this country, has been due principally to three causes: first, the ability and enterprise of those who have been identified with the progress of electrical industries, since electric illumination became an economic fact instead of a laboratory-experiment: sec ondly, the readiness of the American people to adopt new and ad vanced methods as soon as their superiority has been fairly demon strated; and thirdly, tile economy and flexibility of the apparatus employed, when properly designed and constructed, and installed under suitable conditions. Basing our judgment on the world's advance in scientific devel opments during the past century, we may reasonably conclude that in no other country would the pioneeis of electrical invention, whose names have now become household words, have received the prompt and plentiful financial support which has enabled them to inaugurate undertakings of exceptional magnitude, even in this era of tremendous monetary organizations. And, on the other hand, we have seen, in the numerous financial and engineering failures inseparable from such rapid development, the natural results of a too implicit faith in electrical omnipotence. It is not to be wondered at that conservative engineers have been slow to adopt this new and mighty agent in the solution of exten sive problems, and under circumstances where a single failure means not only a greater or less financial sacrifice, but the loss, in a greater or less degree, of professional reputation. Be mechanical engineer, while recognizing the fact that thousands of horse-power are to-day transmitted by electrical means, from sunning the lathe in a dentist's office to the operation of a fifty-ton travelling crane; from passing a cooling draught of air through a

Jan 1, 1891

By R. A. Hadfield

It seems a specially fitting opportunity to present a paper on the alloys of iron and aluminum at the New York meeting of this Institute, owing to the fact that America has, more than any other country, originated and developed the manufacture of cheap aluminum. The Cowles, Castner, and Hall systems have all originated in the ever-busy brain of our cousin across the water. The problem of cheaply producing this valuable metal has been a difficult one, but to the writer it seems that the more arduous the task the greater the delight with which our American friend attempts to overcome the difficulties surrounding it, and the more vim he throws into the work. Another and equally striking proof of this is to be found in the recent appearance of the already wellknown remarkable work, The Mefallurgy of Steel, by Mr. H. M. Howe, of the Institute of Technology, Boston, Mass. It is to be hopel that this Institute will not be slow to recognize by some special mark its appreciation of this signally valuable and original work. The writer has been led to describe the following experiments, believing that so far no full and exact report has yet been presented to this Institute as to the effect of aluminum alloyed or combined with the metal iron. It has been a special object to make the material as far as possible a true alloy or combination of aluminum and iron, with as small quantities as possible of other disturbing ingredients, such as silicon, manganese, etc. In the material described in these experiments, the total amounts of other elements present (sulphur and phosphorus being disregarded as present in such small quantities) do not exceed about 0.5 per cent. Such material may therefore be probably taken as fairly illustrative of the effect of the metal aluminum upon iron. Since completing the experiments the writer

Jan 1, 1891