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By John Birkinbine

Forty years ago, when the first shipments of iron-ore were made from the Lake Superior region, the supply for the blastfurnaces active at that date was in most cases a local consideration ; the majority of the smelting-plants being close to the oremines. Of those which depended in whole or in part upon ores brought from distances greater than an economical wagonhaul, few obtained supplies by canal or railroad from points 50 miles removed. At the present time the ore-supply is a local consideration for but a small proportion of American blast-furnaces, and 700 miles or more separate a greater num-

Jan 1, 1898

By M. E. Wadsworth

The chief value of a paper like this consists in its statistical tables, putting on record material useful to future inquirers. The data here given have been compiled from time to time as far back as 1874, and subsequently brought up to date. Much of the data could only be procured by personal inspection of the catalogues, as for example those relating to the Lawrence Scientific School, which were taken at that time from the catalogue of Harvard University, on file in the University Library, by the present writer, then an instructor in that institution. These tables of statistics were first prepared for publication by the present writer in 1888-1890 and published in his "Report to the Board of Control of the Michigan College of Mines " (Michigan Mining School) for 1886 to 1890. Later they were revised, enlarged and brought down to date in his reports to the same Board for 1890-92; and since that time they have been, at his request, revised, greatly enlarged and kept up to date by Mrs. Frances H. Scott, the efficient Librarian and Secretary of the Michigan College of Mines. Great credit is due to her for her devotion to this work and her untiring efforts to have the statistics complete as far as possible. The accompanying running commentary is given simply as a string to hold these statistics together, and in order to call attention to a few points. In compiling any tables like those accompanying this paper, one is confronted by serious difficulties, some of which render these results only approximate. In order to insure greater correctness and fullness in the statistics to be published the writer's reports for 1890-92 were sent to the president of every college, university, and technical school in the country, so far as known. Accompanying this was a personal letter which asked of each one his aid in correcting any errors, and in giving fuller statistics. But relatively few answers were obtained, and subsequently from one to many letters have been sent to each institution not formerly reply-

Jan 1, 1898

By Guy R. Johnson

It is a common observation among those engaged in the ironbusiness, that the lower (i.e., the less graphitic) grades of pigiron show a rough face on the pig. As such irons are always low in silicon, the generally accepted belief is, that this rough face is due to the absence of silicon. Certain investigations, however, made by the writer on Embreville pig-iron, and extending over nearly a year's time, seem to indicate another cause, namely, the giving-off of included gases, particularly sulphurous oxide (SO2,). It is, of course, the tendency of such gases to rise through the iron, escaping into the air; and the more liquid the iron, and the longer it remains liquid, the greater the chance for such escape. The lower grades of iron, being always colder, tend to solidify early, and before the included gases can completely escape.

Jan 1, 1898

By Nelson P. Hulst

To those who have had the happy privilege of friendship with George W. Goetz, the announcement of his death has brought great sadness. He was born in Milwaukee, Wisconsin, February 17, 1855, and died January 15, 1897. In his boyhood days, when I first came to know him, his frank, trustful manner; his eyes brimming with truthfulness; his eagerness, never obtrusive, to gain knowledge from all whom he met; and his equal readiness to give without ostentation of his store, constituted a personality which at once commanded confidence and won friendship. I am told that as a scholar of five years he was conspicuous for brightness, a show-pupil, who was called on to recite when visitors were present at school. Yet this in no way spoiled him. His modesty was too strong a trait in his character to be overcome by any attention which might, be expected to arouse vanity. In his simple-heartedness he was pleased then, as he always was in his maturer years, to give of his knowledge for the gratification of his listeners, with never a thought of himself. So strong was this characteristic that in a brief autobiography, in the form of a letter to his wife and children, found among his papers, he excuses himself to them for recounting what he had accomplished in his life-work. As a preface to this autobiography (which, it seems, was prepared on the eve of a sudden journey to California, taken February, 1895, for his health) he says: " I am writing this rather hastily, and I

Jan 1, 1898

By Alfred E. Hunt

By the death of Joseph Dame Weeks, past-President of this Institute, which occurred December 26, 1896, the world has lost an earnest and unwearied philanthropist; the Christian church, a zealous, active and consistent representative; the United States and the State of Penusylvania, a patriotic, pub-

Jan 1, 1898

Jan 1, 1898

By Alfred James

Some months since, in the Johannesburg gold-fields of South Africa, the attention of the author was directed to certain statements to the effect that the gold-contents of foul or extremely dilute cyanide-solutions could not be effectively precipitated in practice by the usual zinc-method. Such statements caused all the greater surprise, because it is well known that this difficulty is not encountered in other wellknown districts, as, for example, in New Zealand, where solutions containing less than 0.05 per cent. of KCy are regularly reduced in practice to below 1 grain of gold per ton, while in Mexico and the United States almost equally satisfactory precipitations are not uncommon. As a result of these representations, however, the author visited several plants at work in the Transvaal, and noted that while at some few mines the precipitation was really excellent, at others the effluent, after treatment, was much too high in bullion-contents. An investigation into the causes of these unsatisfactory results disclosed the fact that more attention to the close packing of the zinc-shavings in the extractor-compartments tended to improve the results, even with the most dilute solutions. The function of the zinc being one of surface, it stands to reason that a compartment well filled with zinc would be more effective than a half-filled one. Moreover, the quality of the zinc was inferior. This should be in long, tough, thin, light threads; light enough to ignite readily, and tough enough not to disintegrate easily into a slime. The coarse shavings too frequently employed appear to give the reverse of the best practice ; they are brittle, contain less surface, and take up more room. It is almost impossible to pack a compartment properly

Jan 1, 1898

Jan 1, 1898

Jan 1, 1898

Jan 1, 1898

By Charles Catlett

Much has been done of late years to facilitate preliminary stratigraphical investigations, and for examination at considerable depths and in a certain character of material the diamonddrill, in its general forms, certainly stands pre-eminent among the tools for such work. But there are large classes of deposits —indeed, I may say the larger proportion in which ordinary. prospecting is done—which lie near the surface and are interbedded with soft and fine material. The method usually employed for prospecting these is by means of small shafts. These are sunk with considerable slowness and at considerable expense, depending largely upon the character of the material encountered, and are greatly interfered with by water. In this region the smallest are 3 by 4 feet, but they are usually considerably larger. Having had occasion during the past year to do a large amount of prospecting work, I have found the use of a hand-auger and drill of immense value in this respect, and in my practice it has largely superseded, and always preceded, the other forms of investigation. I believe that the information desired mas

Jan 1, 1898

By E. J. Longyear

The rapid development of the Mesabi range has been a matter of much wonder to those familiar with ore-deposits elsewhere, and much skepticism was shown when " millions of tons of ore on the Mesabi" was first reported. Now, however, with over 8,000,000 tons to its credit at the close of 1896, a prospect of 3,000,000 more this year, and more ore " in sight" than ever before, it is evident that the first claims for the range were not so greatly exaggerated as perhaps even those who made them thought they were at that time. An explanation of the ease with which these deposits have been explored is found in their mode of occurrence. Lying in flat beds and near the surface, and only exceptionally occurring under a taconite " capping," the prospector had only to sink a few vertical test-pits on a fortyacre tract down to the rock to be reasonably sure whether his property contained ore or not. If he found ore in one or more of these preliminary pits, he would then fill in with more pits until the ore-area was entirely outlined by test-pits from 200 to 400 feet apart. In the early days of the range the testing was almost entirely done by digging pits with pick and shovel. When water was encountered, work had to be stopped, unless a steam pumping-plant was put in, resulting in greatly-increased expenses. Latterly, drills have been used with great success in continuing the exploration after water has been struck in the pit, rendering further progress with pick and shovel impracticable. There are several kinds of drills in use. The diamond-drill is largely used, and possesses the advantage of being in readiness to drill rock if thought advisable, the taconite being very hard and almost impossible to drill except by the use of diamonds. Some form of churn-drill has been much used. This may be either a steam- or a horse-power-drill. The principle is the same in each, the cutting being done by percussion instead of by rotation, as in the case of the diamond-drill. A churning motion is given by passing a rope from the top of the

Jan 1, 1898

By F. W. Denton

Much has been written about the possibilities of the Vermilion and Mesabi ranges of northern Minnesota as producers of large quantities of high-grade iron-ore. The Mesabi range in particular has attracted considerable attention on account of the proximity of the ore-deposits to the surface, which has been as-

Jan 1, 1898

By R. W. Raymond

Most of US, in this hurrying age, take little pains to preserve such records of our doings as will make the work of' our biographers easy. Now and then there is an exception, and Dr. Trippel was one. Methodical in all his habits, he kept diaries and journals comprising his own personal experiences, the details and results of his numerous scientific investigations, and his impressions concerning men and events; and also copies of all his technical essays, published by various societies or periodicals. It is a striking instance of " the irony of fate," that these carefully-preserved materials, which would now have a real historical, as well as biographical value, were totally destroyed by an accidental fire a few years ago. In addition to my own recollections of an acquaintance covering more than thirty years, I am indebted, for the fads upon which this sketch is based, chiefly to Mr. Engene J. Trippel, a son of the deceased, and now Register of the United States Land Office at Tucson, Arizona. Mr. Trippel, however, frankly confesses that his own knowledge of his father's work is, in the absence of written records, imperfect.

Jan 1, 1898

By Persifor Frazer

General Geology of the Northern Black Hills. The " Black Hills of Dakota," to the northern part of which the following observations apply, occupy a position on either side of the boundary between Wyoming and South Dakota, approximately between 103" 15' and 104" 48' of west longitude and 43 15' to 43" 50' of north latitude. The area is roughly 4160 square miles.* (See Plate I.) As has been pointed out by Profs. H. O. Hofman, I?. R. Carpenter and others, and illustrated by Mr. Newton in the publications of the United States Geological Survey, these hills are made up of a large number of the known formations from the Archean to the Tertiary, which latter constitutes the border of the region. The mining operations are largely confined to the interior of this area, and the centers from which they are conducted (Deadwood, Lead City, Galena, etc.) are situated near the line of junction of the Archean schists and quartzite, supposed to represent the Potsdam Sandstone of the N. Y. series, or the lowest of the Paleozoic measures. The Archean or pre-Paleozoic rocks consist mainly of a mica-schist in which hornblende and garnet are frequently

Jan 1, 1898

By Edward Keller

In order to conduct intelligently the sampling of copper of various forms and grades, solid or in molten furnace-charges, a knowledge of this subject is essential. Yet figures and tests have been persistently withheld from publication, and the books at our command give us little or no information in this regard. This gap in our copper-literature has led to a series of experiments, the results of which are given below. Nearly all gold- and silver-bearing copper, destined for shipment, is cast into the form of bars or pigs. For the sampler, the question arises, Does copper, so cast, remain homogeneous ? If it does, sampling should present no difficulties; but, from experience, we know that this is not the case, and we are thus led to study the behavior of the precious metals arid impurities in copper when the latter changes from the molten to the solid state. For the purpose of the experiments here described, all available grades of copper were selected, and all of them mere subjected to the same conditions, an important requisite for proper comparison. The molten copper obtained directly from reverberatory- and blast-furnaces was cast in a cast-iron mould, the sides and bottom of which were 1 inch thick, and would, therefore, give the copper a fair length of time to chill. The inside dimensions of the mould, and, consequently, of the block of copper obtained, were: length, 10 inches; width, 9 inches; and depth, 5 inches. Fig. 1 illustrates the method employed to obtain samples from these blocks. A was cut away, and the face so produced BALTIMORE COPPER WORKS,

Jan 1, 1898

By R. W. Raymond

This paper is simply a summary, prepared at the request of the Council of the Institute, of the report of Mr. Albert Ladd Colby, of South Bethlehem, Pa., presented at the New York meeting (October, 1896) of the Association of American SteelManufacturers, on " The Advisability of the Endorsement by the Association of the United States Standard Gauge, approved by Act of Congress, March 3, 1893, to the Exclusion of the Birmingham Gauge, the .Brown and Sharpe, and all Others:" a subject on which, at the Pittsburgh meeting (April, 1896) of the said Association, Mr. Colby had been appointed as a committee. The report favors the adoption, not of the United States standard gauge to the exclusion of others, but of a decimal system of gauging all materials in thousandths of an inch, thus doing away entirely with arbitrary gauge-numbers running in inverse order to the actual thickness. The American Institute of Mining Engineers originated this movement. The report of its committee on a standard wiregauge, presented in October, 1877,* recommended the abandonment of the system of fixed gauges for commercial use, and of the system of representing the diameters and sizes by numbers, and the adoption, in lieu thereof, of the system of expressing sizes in thousandths of an inch or fractions of a millimeter, and the use of the micrometer-gauge as a means of measuring sizes. In 1892 the American Society of Mechanical Engineers appointed a similar committee, and corresponding action was

Jan 1, 1898

By D. H. Bacon

Nearly all men are too busy with their own affairs to keep informed of the progress in other lines. From time to time we read statistics showing the development in some industry that astonish us; but the feeling of surprise soon fades: to be followed by others that likewise pass away. A short resume of what has been done in one line may be of interest. Down to late in the fifties the ore-product of Lake Superior mas handled over a mule-tram-road to Marquette; now the Duluth, South Shore and Atlantic, the Chicago and Northwestern, the Wisconsin Central, the Duluth, Superior and Western, the Duluth, Mesabi and Northern, the Duluth and Iron Range and the Lake Superior and Ishpeming railroads serve the shippers. Down to nearly 1870 a 700-ton ship was an enormous craft, the loading of which required two days; the unloading being seldom accomplished in that time. In 1871 the largest ore-barge carried 1050 toils and made twelve trips per season. Now the cargoes reach 5000 tons, the loading requiring less than three hours, and the unloading ten hours. Now the mines cover more land than was familiar to even the " timber-cruiser " when the Jackson mine was opened. The annual shipments have grown from a few thousand to 10,000,000 tons, and the ability of the mines to produce is not taxed. Lake-freights are at one-eighth, and rail-freights at one-quarter, of early prices. The deeper waterways, commodious locks and large ships of to-day are in a greater measure due to the movement of ore than to any other cause. Great savings have been made in each detail of each department. The only item of cost that has not been lessened, I am glad to say, is the money paid to men. Wages, measured by what they will buy, are as high

Jan 1, 1898

By George W. Maynard

For an account of the discovery and the determination of chromite on Port au Port Bay I am indebted to Mr. Obalski, Government mining engineer for the Province of Quebec. He writes: " In June, 1894, with the authorization of our Government, I went to Newfoundland to examine some asbestos property. Passing through Halifax, I had interviews with some gentlemen who told me that besides the asbestos there was in the same district a big deposit of iron-ore. They handed me some specimens, and, after ascertaining that they were not magnetic, and learning that they were found in serpentine, I said they were chromic iron. I visited the place on June 27, 1894, and confirmed my opinion, pointing out at the same time the importance of the deposit, as appears in my report of July 9, 1894. I do not claim any credit for the discovery of chrome-ore in Newfoundland; but, as a matter of fact. when I came in contact with the Halifax gentlemen they did not appear to know the nature or the value of the mineral until I mentioned to them that it was chromite. "' Mr. Obalski's report was mainly devoted to the asbestos-deposits. That portion relating to the chromite was as follows: " On the right side of the creek there is a show of chromic iron of good quality, which appears scattered through the serpentine in several places on the face of the cliff for 40 to 50 feet. A few boulders are found farther up at a distance of 100 feet, and also in the ckeek itself. From this point the deposit exists on a relatively large area, the widest exposures being from 6 to 7 feet. Chromic iron deposits in serpentine rock have no regularity, and are merely pockets. In the case of the property in question this rule is not changed, but the pockets look to be of large extent, and could be easily worked." My own preliminary investigation of the property was made

Jan 1, 1898

By Robert H. Richards

The adaptation of European methods of concentrating ores to suit the conditions of this country has followed the lines that simplify machinery, diminish labor and increase capacity. Noteworthy instances are the substitution of hydraulic classifiers for the last one or two trommels in the series, and the substitution of a distributing-tank for the slimes in the place of the Spitzkasten. The question may be fairly asked, At what point do losses become serious in consequence of these changes? It is to study this question that the investigation herein described has been undertaken. After the losses are located and the methods of stopping them are pointed out, it will then lie with the individual mill to decide whether or not the plans proposed will save suficient value to warrant their adoption. In the discussion of sorting followed by sizing, as the terms are used in this paper, me have to deal with the preparation of slimes by the Spitzkasten for subsequent washing upon the slime-table. The Spitzkasten, or pointed box, is an inverted hollow pyramid, generally of wood, usually with four faces or sides coming together in a point below. The sides can have, according to Rittinger, a minimum angle of slope of 50" with the horizontal. The feed-water carrying fine slimes (less than 0.01 inch, or 0.25 mm. in diameter) for treatment is fed at one end and carefully distributed over the whole width. The outlet is over the opposite end. The water-current passes direct from inlet to outlet, and has usually been regarded as a surface-layer pass-

Jan 1, 1898