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By J. R. Campbell

THE need for standardizing methods of arriving at definite conclusions regarding the cleanability of a given coal, and for measuring the performance of coal-cleaning equipment, is constantly increasing. Earlier notes by the author on this subject are amplified in this paper, because he believes that better preparation of bituminous coal is a partial solution of the coal operators' troubles. WASHABILITY STUDIES The term "washability" of coal was coined when washing was the universal method of separating coal from its impurities by utilizing their difference in specific gravity. This and analogous terms are still used in their broad sense although pneumatic or air separation is now used to clean coal. These terms are so used in this paper. Too much time or money, can hardly be spent on "feed surveys" to get a "picture" of the coal that is to be cleaned. There have been too many "rule of thumb" methods used. Screen analyses and "sink-and-float" tests on the raw coal enable the coal operator and washery man to predict within reasonable limits the results that may be expected from any efficient cleaning apparatus.

Jan 1, 1928

By Raymond O. Ladoo

FUSED quartz is a glass made by the fusion of nearly pure silica. Some confusion in terminology exists but in the trade today "fused quartz" generally refers to the perfectly transparent colorless product made from rock crystal whereas "fused silica" is a white, translucent product made from silica sand. Vitrified silica is the term preferred by purists for all quartz glass, but it lacks the definiteness of -the trade terms. Since the raw materials, methods of production, and properties of the finished products arc different for the two types, the trade terms are preferred. As fused quartz is amorphous, it-physical properties differ greatly from those of quartz crystal. Lacking crystallographic directions and having no piezo-electric properties, fused quartz. of course, has no value for the making of radio oscillator plates; but it does have other valuable and unique properties. Perhaps the 'best known and most useful properties are its extremely low coefficient of expansion and its ability to transmit short-wave ultraviolet radiant energy. Crystal quartz not only has an aver-

Jan 1, 1947

The notion prevails that writing is a knack, that the skilful use of the pen is a gift of nature. This is an error. Dogberry may be responsible for it; he said: "To be a well-informed man is the gift of fortune, but to write and read comes by nature". Because Dogberry said it, we may be sure that Shakespeare thought otherwise. Ability of any sort may be partly innate, but my own observation and experience lead me to conclude that most of the easy writers have become so by constant practice. As I recall the names of men successful with the pen, I remember that most of them have written a great deal and have taken particular pains to improve their style. The suggestion that proficiency in the difficult art is a happy accident provokes a sardonic smile. The larger part of the great writing in our literature is the result of persistent effort. An easy fluency has been the undoing of many; their flamboyant and fantastic scribbling has proved as perishable as froth. This criticism applies to technical writing also; in order that a technical description or discussion may hold the interest of the reader, at least long enough to cause him to read it to the end, the writing must be done carefully and systematically; otherwise it will fail in its purpose of conveying information. Clearness is absolutely essential. "It is not enough to use language that may be understood; it is necessary to use language that must be understood."* The purpose of writing, at least of that which is meant to be read by others, is not only to express ideas but to communicate them. Lack of perspicuity may prove as bad as

Jan 1, 1931

By T. A. Rickard

The notion prevails that writing is a knack, that the skilful use of the pen is a gift of nature. This is an error. Dogberry may be responsible for it; he said: "To be a well-informed man is the gift of fortune, but to write and read comes by nature". Because Dogberry said it, we may be sure that Shakespeare thought otherwise. Ability of any sort may be partly innate, but my own observation and experience lead me to conclude that most of the easy writers have become so by constant practice. As I recall the names of men successful with the pen, I remember that most of them have written a great deal and have taken particular pains to improve their style. The suggestion that proficiency in the difficult art is a happy accident provokes a sardonic smile. The larger part of the great writing in our literature is the result of persistent effort. An easy fluency has been the undoing of many; their flamboyant and fantastic scribbling has proved as perishable as froth. This criticism applies to technical writing also; in order that a technical description or discussion may hold the interest of the reader, at least long enough to cause him to read it to the end, the writing must be done carefully and systematically; otherwise it will fail in its purpose of conveying information. Clearness is absolutely essential. "It is not enough to use language that may be understood; it is necessary to use language that must be understood."* The purpose of writing, at least of that which is meant to be read by others, is not only to express ideas but to communicate them. Lack of perspicuity may prove as %ad as

Jan 1, 1931

THE sessions of the Institute were opened on Tuesday evening, October 26th, at Garrett's Hall, by Mr. Charles A. Otis, Chairman of the Local Committee of Arrangements, who welcomed the Institute to Cleveland, and introduced Col. Charles Whittlesey, who ad¬dressed the Institute briefly on the coal deposits of Ohio. Col. Whittlesey described the situation and character of the coal-beds of the State, and gave a short history of the use of raw coal in the manufacture of pig-iron, and spoke of the excellent quality of metal produced. The aid that a body of scientific miners and metal¬lurgists were capable of giving in the development of coal and other mineral resources was dwelt upon, and the hope expressed that the visit of the Institute to Cleveland might be profitable as, well to its members as to the citizens of the State. The President, Mr. A. L. Holley, responded to the welcome of Mr. Otis and of Col. Whittlesey, and read an introductory address on Some Pressing Needs in the Iron and Steel Manufacture. The following members and associates, duly proposed and indorsed by the Council, were then elected MEMBERS. Alfred S. Bertolet, - Youngstown, Ohio. Henry Binnse, - Chicago, Ill. John Birkinbine, - Philadelphia. Andrew A. Blair, - Watertown Arsenal, Mass. Ogden Bolton, - Canton, Ohio. Lloyd Booth, - Youngstown, Ohio. E. Borda, - Philadelphia. N. P. Bowler, - Cleveland, Ohio. Alexander E. Brown, - Cleveland, Ohio. C. F. Brush, - Cleveland, Ohio. S. M. Carpenter, - Cleveland, Ohio. James Cartwright, - Youngstown, Ohio. Henry Chisbolm, - Cleveland, Ohio. Wilson B. Chisbolm, - Newburgh, Ohio. W. H. Clarke, - Millertown, Pa. James E. Clayton, - Ore Knob, N. C.

Jan 1, 1876

Jan 1, 1927

Jan 1, 1892

The sessions of the Institute were opened on Tuesday evening, October 26th, at Garrett's Hall, by Mr. Charles A. Otis, Chairman of the Local Committee of Arrangements, who welcomed the Institute to Cleveland, and introduced Col. Charles Whittlesey, who addressed the Institute briefly on the coal deposits of Ohio. Col. Whittlesey described the situation and character of the coalbeds of the State, and gave a short history of the use of raw coal in the manufacture of pig-iron, and spoke of the excellent quality of metal produced. The aid that a body of scientific miners and metallurgists were capable of giving in the development of coal and other mineral resources was dwelt upon, and the hope expressed that the visit of the Institute to Cleveland might be profitable as well to its members as to the citizens of the State. The President, Mr. A. L. Holley, responded to the welcome of Mr. Otis and of Col. Whittlesey, and read an introductory address on Some Pressing Needs in the Iron and Steel Manufacture. The following members and associates, duly proposed and indorsed by the Council, were then elected MEMBERS. Alfred S. Bertolet,.. .. . Youngstown, Ohio. Henry Binnse,. Chicago, Ill. John Birkinbine,.. .. . Philadelphia. Andrew A. Blair,. .. .. Watertown Arsenal, Mass. Ogden Bolton,. .. .. Canton, Ohio. Lloyd Booth,..Youngstown, Ohio. E. Borda,..Philadelphia. N. P. Bowler,.. .. . Cleveland, Ohio. Alexander E. Brown,.... Cleveland, Ohio. C. F. Brush,.. .. .Cleveland, Ohio. S. M. Carpenter,.. .. . Cleveland, Ohio. James Cartwright,.. .. . Youngstown, Ohio. Henry Chisholm,.. .. . Cleveland, Ohio. Wilson B. Chisholm,.. .. . Newburgh, Ohio. W. H. Clarke,.. .. . Millertown, Pa. James E. Clayton,. .. .. Ore Knob, N..C.

Jan 1, 1913

By AIME AIME

OUR own Institute of Metals and Iron and Steel divisions cooperated with the Iron and Steel Division of the American Society of Mechanical Engineers, the American Welding Society, and the American Society for Steel Treating in a busy week at Cleveland. The morning sessions were held at the Hotel Cleveland and the afternoon ones at the Auditorium, where the metallurgical exhibition under the auspices of the American Society for Steel Treating not only occupied the arena of the Auditorium but completely filled the huge adjacent Annex. In the intervals of sessions the members thronged the exhibits but in the evenings the local attendance was so great that if the crowds had been any larger it would have been difficult to see the exhibits. With so many firms, both producers of metals and of equipment accessory to their production and use, it would be impossible to mention them -all and unfair to single out a few, since no two individuals' judgment would coincide as to relative interest and importance. In any case an exhibit is a thing to be seen rather than described, and these were well worth seeing.

Jan 1, 1929

By Earnest R. Woakes

Those engaged in pumping from shafts, or other mining works, may be intereited in the following suggestion of what is believed to be a novel method of raising moderate quantities of water against a considerable head. It is admitted that the ordinary Cornish pump, as generally used in mines, is hard to beat, on account of both its extreme simplicity and its easy adaptation to the requirements of mining; its great drawback, however, being the enormous weight of heavy rods and successive plungers that have to be kept in motion, not to mention the necessary " balance-" and " angle-bobs," with all their accompanying friction and wear and tear. It is contended that the following method would, to a great extent, overcome these drawbacks ; though, no doubt, many old miners may say it would also introduce new ones. Possibly, this may be the case. It is only desired that this pump may be judged upon its merits. The chief novelty of the method consists in employing the almost unlimited pressure obtainable from a high column of water, augmented, if necessary, by a hydraulic ram or press at the top, to work a small-diameter piston or plunger at the bottom of a shaft or well. This high-pressure plunger, indicated at E, in Fig. 1, transmits power direct to a larger-diameter plunger, F, constituting, together with the ordinary H-piece, valves, and wind-bore, the actual pump, which raises the water, by column C, to the adit-level or other discharge, placed as far as possible below the head of the high-pressure column A and ram W. It will thus be seen, that it is only necessary to maintain a prmsnre on the small piston, E, equal to that on the larger one, F, by means of the small but high column of water, A, in order to cause F to descend, and thus force the water up through C. The up-stroke is accomplished by a small water-wheel, or other engine, connected to the light rod or wire rope B, this having only to raise the weight of the actual plungers and fill the H-piece with water from the tank or

Jan 1, 1892

By Nathaniel Herz

The formula very frequently used for computing the economical size of pipe to transmit compressed air is that of D'Arey, as follows: D = cV w1l Where, D = the volume of compressed air delivered in cubic feet per minute, at the final pressure. c = an experimental coefficient determined for the various sizes of pipe, d = the diameter of the pipe in inches. 1 = the length of the pipe in feet. p, = the initial gauge-pressure in pounds per square inch, p2 = the final gauge-preesure in pounds per square inch. w1 = the density of the air, or the weight in pounds per cubic foot at the initial pressure, p1. The most common case is that in which the given quantities are: the quantity of air required, the length of the pipe, and the initial pressure. The method of solution is to assume a pressure-loss and to compute the remaining factor, cd5, thus giving the size of pipe corresponding to the assumed loss of pressure. It is always desirable to try two or more pressure-drops, in order to find the combination that is most satisfactory, since often a small change in the size of pipe will reduce or increase the loss of pressure several pounds. An alternative method is to assume a size of pipe and calculate the corresponding pressure-drop. Each method involves a series of tedious calculations to arrive at the most economical solution, and also requires the use of tables giving the constant, c, the density of the air, w1, and often, for convenience, a table giving the values of the expressions p1-p2 and c J I hare constructed a graphic chart, Fig. 1, for the solution of

Jan 1, 1913

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 E. P. Jennings

Large deposits of titaniferous iron-ore occur at Caribou, an old silver-mining camp in Boulder county, Colo., 17 miles west by south of Boulder, and a few miles northwest of the tungsten-mines. Professor Regis Chauvenet1 published a part analysis of the ore many years ago, but gave no description of the wall-rock. Caribou hill, which contains both the silver-bearing veins and the iron-ore deposits, is a low dome of gabbro surrounded by the Archæan schists and gneisses of the Front range of the Rocky mountains, the peaks of which, a few miles west of Caribou, attain an elevation exceeding 12,000 ft. The gabbro stock is roughly elliptical in outline, with approximate diameters of 1 and 3 miles. The crest of the dome is 10,500 ft. above sea-level, and the town and ore-cleposits are 500 ft. lower. Outcrops of the iron-ore occur in the town and extend NW. for 2,000 ft., where they disappear under the swampy meadows of Caribou park. Portions of the deposit are covered by drift, but one continuous outcrop is 900 ft. long and from 200 to 250 ft. wide. A second deposit is 0.25 mile south of the town along the eastern slope of the hill. It is not as well defined as the north bed, but is approximately 1,000 ft. long and from 100 to 200 ft. wide. The easily disintegrated ore does not form prominent outcrops, but the outlines of the deposits are readily traced by the large amount of ore fragments that cover the ground. Trenches and pits sunk on the outcrop expose a roughly banded magnetic iron-ore, with pyroxene as the principal gangue-mineral. The Gabbro. This rock was classified in the field as a gabbro from the presence of pyroxene and striated feldspars, and for convenience the field-name will be retained.

Jan 1, 1913

By Henry W. Turner

The following notes were taken on a trip through northern Korea in the fall of 1910. We started with about 19 Korean ponies, and as many Koreans, from Shin Anju, on the railway from Seoul to Antung. We passed through the ancient walled city of Anju, and thence up the valley of the Anju river. We then crossed over to the north into the Kalsan drainage, thence over another divide to the Chasung river, and finally reached the old Korean copper-smelting camp of Tong Jom— in all a distance by trail of about 200 miles. The return trip was made with ponies to Mampochin on the Yalu river, and thence' down the river in a junk to Antung. The route of travel is shown on the sketch map, Fig. 1.

Jan 1, 1913

By Elwood Haynes

As in organic nature certain animal and vegetable forms have undergone modifications, and thus, as it were, fitted themselves to live in a new environment, so it has been found possible in certain instances to form new metallic combinations which are practically immune to the natural conditions that exist on the earth at the present time. A few of the metals, such as gold, silver, and the metals of the platinum group, are found native, but the commoner heavy metals are nearly always found in the form of oxides or sulphides. For a number of years I have made experiments with a view to finding certain metallic combinations or alloys which would not only resist oxidation and other harmful influences, but would also possess valuable physical properties, which would render them fit for special service. The first decisive step made in this direction was the discovery of an alloy of nickel and chromium in 1898. The properties of this alloy have already been described in a previous paper.' Immediately following the discovery of the nickel-chromium alloy, I produced an alloy of cobalt and chromium, which has likewise been described in the reference given, but the range of proportion between the cobalt and chromium is so great, and the combination is modified to such a marked degree by the introduction of other substances, that I have felt justified in reading another paper on this subject, describing more fully my researches in this particular direction. As early as 1907 and 1908,I made alloys or combinations of cobalt, chromium, and tungsten; cobalt, chromium, and molyb-

Jan 1, 1913

By John W. Langley

The papers of Mr. W. J. Keep, read before this Institute, have called attention to the influence of aluminum in cast-iron and on iron and steel castings. The information in these papers is interesting and valuable, as showing the modifications which iron undergoes when dosed with sufficient aluminum to form a distinct alloy, the quantity of the alloying metal used being such that the amount remaining in the casting is sufficient to be readily discovered by analysis. The same is also true of the so-called aluminum-steel patented by R. A. Hadfield, where the proportions specified are such as to leave in the finished steel from one-twentieth to one-tenth of one per cent. of aluminum. Whether these alloys are of practical utility or not has thus far . not been proved by any extended tests on a large scale, and until such evidence is forthcoming it may be safely held, provisionally, that such a use of aluminum is of doubtful utility. But there is another function which this metal can perform that has been known for some time, and which has passed beyond the experimental stage, viz.: its beneficial effect in securing sound ingots. It appears to be a general property of all metals when in the fluid state and at a temperature considerably above their points of fusion, to contain gas, either dissolved from the air or frorn the furnace, or else self-evolved by internal reactions. Silver, perhaps, shows this power in the highest degree, and mercury and lead in the least; midway stands steel—the quantity of gas which it can hold in solution, or " occlusion " as it has been called, varies with its temperature, its composition, and its mode of manufacture. When the steel sets in the mould, a portion of this gas escapes, causing blow-holes, surface defects, boiling-over, wildness, and quite a long train of troubles, familiar to all practical steel-makers. Ferro-silicon has long been used as a quieting agent. The first extended use of it for this purpose was made at Terre-Noire, in

Jan 1, 1892

[A discussion suggested by the paper of Mr. James Gsyley on " The Development of American Blast-Furnaces," read at the New York meeting of the Iron and Steel Institute, October, 1890, and reprinted from the Journal of that Society in Bans. A. I. M. E., xix., 932.1 (Cleveland Meeting, June, 1891.) [Kote by the SecretaRy.—The three following contributions to this discussion were communicated by letter to the Secretary of the Iron and Steel Institute, and were received by me too late for insertion in vol. xix. of the Transactions.] FRed. W. Gordon, Philadelphia, Pa.: Mr. Gayley's paper calls our attention to the very expensive blunder hitherto made in blowing too much wind in a given size of furnace. It was quite evident from an analysis of blast-furnace operations that the work we are doing in America is anything but creditable. We were consuming fully 1000 pounds of coke more than is necessary for each ton of iron made, and were hammering the linings of our furnaces out in a very short time, and nothing but the very high price of pig-iron would stand the drain. It had long been my pet scheme to gradually reduce the quantity of air, at the same time increasing the burden to the maximum and decreasing the limestone, and determining, if possible, the fuel economy which might be reached consistently with the maximum production of the furnace. After the success of the Isabella furnace at Pittsburgh, which was remodelled in 1880, the North Chicago Rolling Mill Company had

Jan 1, 1892

By C. M. Myrick

The following notes are submitted in the belief that they may interest some of the many owners of mall water-power plants, so generally used in mining-work throughout the West. A small and somewhat primitive quartz-mill was taken over by a leasing company, and a 10-stamp battery was installed. Originally, power had been furnished by a Pelton wheel; but, since the supply of water depended on the rate at which snow was melting 011 the mountains, a steam-plant had been added to help out during cold spells. This auxiliary plant was antiquated and expensive to operate, and, soon after starting up the remodeled mill, it broke down completely; so that it became neceseary to get all the power possible out of the Pelton wheel, with its ever-varying water-supply. The pipe-line, about a quarter of a mile long, was made up of assorted sizes, from 7 to 11 in. in, diameter; and, since it was buried deep under snow, there were no data from which to calculate the theoretical size of the nozzle. The stream being at this time at a low stage, it was important to make the most efficient use of the available water. This was done by using a nozzle large enough to pass the whole supply—taking care, however, to limit the size so as not to lower the water-level in the tank at the head of the pipe-line. As the weather became warmer, the nozzles were gradually enlarged to meet the increasing volume of water; but a point was finally reached where further enlargement only gave decreased power. Evidently the loss from friction had more than balanced the gain from the increased flow through the pipe. However, the area of nozzle that developed the maximum power from the pipe-line had been found. This was used; and the surplus water was allowed to run to waste at the head of the line.

Jan 1, 1913

By Robert Forsyth

In working the Bessemer process, the bottom of the converter has always been a source of trouble and annoyance, and the subject of more experiments, probably, than any other part of the complex mechanism called a Bessemer plant. This will not appear remarkable when the duties this important piece of refractory material has to perform are taken into consideration. In the first place, by means of the tuyeres, it delivers at a high pressure the air necessary for the conversion of the bath of metal, and has then to resist the intense