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By Richard Pearce

IN looking around me for some subject on which to frame an address for this meeting, it has occurred to me that some results of observation and investigation, in regard to the varied conditions under which gold is found, may possibly prove of interest. The subject is one which frequently crops up in discussions at our meetings, but there is always an immense amount of uncertainty expressed as to the actual condition in which the gold exists in any particular ore. It follows, therefore, that any light which might be shed on this rather complex subject, would be of value to science and of service to mining and metallurgical practice. In some investigations which I have, from time to time, been led to make, for the purpose of determining to what extent an ore might be concentrated, I have been astonished at the very varied and apparently inexplicable results encountered, and have been naturally led to inquire into the causes for such seeming inconsistency. The mines of Gilpin county, Colorado, where gold was first discovered in that State, furnish an infinite variety of examples of its occurrence, and it was here that difficulties first presented themselves to the Colorado miners, in the sudden transition from what is called " free-milling gold-ore " to an ore characterized by properties which make the ordinary treatment by amalgamation stamp-mills utterly impracticable. So long as mining was limited to what might be called the zone of oxidation in the veins, just so long might amalgamation be conducted without difficulty; but directly the miner reached a point beyond the influence of the oxidizing power of the surface waters, the gold resisted all attempts at amalgamation, and recourse • was had to smelting.

Jan 1, 1890

By Ingersoll Olmsted

Mr. D. H. BRowne's paper upon " The Distribution of Phosphorus in the Ludington Mine" (Trans., xvii., 616) has interested me very much, and perhaps I cannot give a better proof of that, interest than an account of my work and observations in the same direction while chemist of the Hudson River Ore and Iron Company. The ores of this company lie in a chain of low hills running northwest and southeast, about three miles back from the eastern bank of the Hudson river, below Hudson, N. Y. They occur in thick veins, with the characteristic Hudson river slate formation as hangingrock and foot-wall, and dip about 45' east, outcropping in many places near the top of the western slopes.

Jan 1, 1890

By John Birkinbine

An unusually large number of crystals of magnetite obtained in the exploitation of a deposit of magnetic iron-ore of remarkable purity, encouraged the preparation of this paper, and its presentation at this time, that the matter might go on record in the Transactions. To make this record more complete, a preliminary statement is offered concerning the district and locality in which the ore is found. To the northeastern portion of the State of New York the United States is indebted for a large percentage of the iron-ore which has assisted in developing the resources and industries of the nation. As early as 1804, iron-ore was mined between Lake Champlain and the Adirondack mountains, and this district has since been an important and continuous contributor to our iron-ore supply. The production of the Lake Champlain district for the last, eleven years is as follows: Years. Gross tons. 1879,...........420,341 1880,...........531,000 1881,...........637,000 1882,...........675,000 1883,...........500,000 1884,...........504,894 1885,...........379,077 1886,...........588,752 1887,...........768,852 1888,...........789,419 1889,...........750,230 Approximate total,.....6,644,565

Jan 1, 1890

By R. W. Raymond

The sudden death of Captain Jones, September 28,1889, became known to his fellow-members on the eve of the Ottawa meeting of the Institute; and at that meeting, Mr. Charles Albert Ashburner, of Pittsburgh, expressed with unaffected feeling and unpremeditated eloquence the sorrow of all. Mr. Ashburner subsequently undertook to revise and extend, for in in the Transactions, the remarks he had made at Ottawa; but death surprised him also, in the midst of his labors; and it has become my duty and privilege to prepare from the memoranda he left behind, the present brief and inadequate notice. To me, who knew and loved them both, this task of double sorrow recalls them both, with a peculiar sense of presence and of absence. They seem to speak from another land, not far away, yet not with human voices—like an echo and its echo. William Richard Jones was born in Luzerne county, Pennsylvania, February 23, 1839. His father was Rev. John G. Jones, a Welsh minister, who had immigrated to the United States in 1832. William was the eldest son, and his father's failing health made it necessary for him to begin early the work of self-support. At the age of ten, he was apprenticed to the Crane Iron company, of Catasauqua, and in this humble capacity entered upon the profession in which he was to become famous. Unquestionably, the thorough acquaintance with all details, acquired by working his way from the bottom to the top, was one secret of the conspicuous executive ability which characterized him in the height of his career. According to a letter from Mr. J. H. Geer, Assistant Chief Engineer of the Cambria Iron Company, Mr. Jones entered the service of that company in 1858 or 1859 as a machinist, and continued to work in that capacity until July, 1862, when he enlisted as a private in the 133d Regiment of Pennsylvania Volunteers, in which he afterwards commanded a company. The regiment was mustered out of service in 1863, and Captain Jones re-enlisted in the 194th

Jan 1, 1890

By H. M. Chance

The Choctaw coal-field is a direct westward extension of the Arkansas coal-field, but its coals are not like Arkansas coals, except in the country immediately adjoining the Arkansas line. From the base of the coal-bearing rocks up to the top of the coalmeasures, I find a total thickness of at least 8500 feet. This great mass of coal-bearing rocks consists of an alternation of slates, shales, sandstones and coal-beds, with their accompanying under-beds of fire-clay. Only one small bed of limestone was observed. This occurs near the middle of the series; it is about eighteen inches thick, and quite arenaceous. The formation is naturally subdivided by seven or eight thick beds of sandstone, varying from 50 to 200 feet in thickness, the outcropping edges of which form a series of more or less bold " hogback " ridges, the interbedded shales and slate forming the intervening valleys. The base of the coal-series is a massive sandstone, ranging from 100 to 200 feet or more in thickness, lying immediately beneath the Grady coal-bed, which is the lowest known coal. In the district embraced between. the Missouri, Kansas and Texas railroad and the Arkansas State line, this sand-rock usually forms a bold semi-mountainous ridge. This is the ridge through which the St. Louis and San Francisco railroad passes at Bryan station, where the Grady coal-bed is opened and worked, from which point it can be traced westward without difficulty, passing about three miles north of Le Flor on the same railroad, thence west to the " Little Narrows " (which is merely a gap in the ridge), 'and beyond to a point two miles west of the Thompson-McKinney place, where it swings abruptly north for a mile or more, only to resume immediately its westward course, forming for some miles the northern boundary of the valley known as the " Boiling-Springs Prairie," beyond which it trends somewhat

Jan 1, 1890

By W. J. Keep

We have shown in former papers the influence which aluminum exerts when added to cast-iron, and we have presented in another paper, accompanying this one, the physical properties of the metal aluminum and of some of its alloys. The present paper continues the investigation. The reader will find, in our paper on "Aluminum and Other Metals Compared,"* explanations not here repeated, which will render the diagrams in this paper intelligible. The scale of stresses is laid off on the ordinate which rises from the zero-point of the diagram. The scale of deflections is laid off on the abscissa which runs horizontally through this zero-point. By applying a given amount of stress, then running back to zero, and again applying the same stress, we describe a spring-line, in which the deflections are proportional to the stresses. Generally the deflections exceed this proportion during the original application of stress; and the excess is the permanent set. By laying off from the zero-point a line parallel to the springline, we shall generally find that this new spring-line and the diagram coincide for some distance; that is, that the test-bar is

Jan 1, 1890

By N. W. Shed

The specifications for bridge-steel are usually not severe. The main difficulty is to secure a material which will roll easily, without showing signs of cracking on the corners of the blooms or on the flanges of the beams. In many mills sulphur has been deemed the most harmful constituent in this respect. It has been thought hazardous.to roll steel containing over 0.07 per cent. of sulphur. Yet, in making steel for the Phoenix Iron Company, I have produced from stock running as high as 0.13 per cent. of sulphur a material which rolled very satisfactorily. It is reasonable to infer that the injurious effect of sulphur can be neutralized, to a great extent, by proper treatment in the open-hearth furnace; and the following notes from my usual practice here may be of interest to those obliged to use high-sulphur stock. The steel made at Phoenixville in the 20-ton furnaces has about the following composition : Per cent. Carbon,...0.15 to 0.20 Manganese,.........0.50 to 0.60 Sulphur,..........0.11 to 0.13 Phosphorus,.: .0.04 to 0.06 Silicon,.......... 0.01 to 0.02 The best running heats were made with a small amount of pigiron. In using large proportions of pig the quantity of ore is also increased. This not only cuts the bottom, but also lengthens the time required to bring the charge down. Up to 50 per cent. of pig may be used, but 25 per cent. is much better. A 40,000-pound charge, containing 10,000 pounds of pig and 30,000 pounds of Bessemer butts or beam-scrap, works very well.

Jan 1, 1890

By William P. Blake

In addition to uintaite, the Uintah Mountains contain a deposit, or vein, of the peculiar hydrocarbon mineral, to which I have given the name wurtzilite, * in honor of the chemist, Henry Wurtz, Ph.D., of New York, who, in 1865, described grahamite, and who has added to our knowledge of the composition of the hydrocarbon minerals. Wurtzilite and uintaite are very similar in appearance, but are very different in their physical and chemical properties. Both are black, splendent and shining in fresh fracture; but the wurtzilite has a decided toughness, and a degree of elasticity, especially when warmed, which suggests to some persons a resemblance to caoutchouc. It was at first, at Salt Lake, believed and reported to be a mineral form of India-rubber, and great expectations of its value as a substitute for crude rubber were indulged in. It was, however, found that it would not act like rubber with sulphur; it would not incorporate with it and become "volcanized," and it was very refractory and insoluble in the ordinary solvents of rubber and of uintaite. The elasticity, though unlike the elasticity of rubber, led to the reference of the mineral to the species elaterite, the only name under which an elastic bitumen is described in the mineralogies; and it is so called in the list of the mineral products of Utah, given in the last message of the Governor of the Territory. The name elaterite, as used by Dana, covers at least three differing substances, ranging in specific gravity from 0.905 to 1.223. Two of the varieties are soft and elastic, much like India-rubber, and one is occasionally hard and brittle, imbedded in the softer kinds. All are rare, and comparatively unknown, and not generally represented in mineral collections. One of the varieties referred to here is the subterranean fungus from Derbyshire, described by Lister as early as 1673.

Jan 1, 1890

By T. C. Mendenhall

All persons, actively engaged in your profession, must have a natural interest in the subject of weights and measures. All members of the engineering profession have to do with operations of weighing and measuring—some with measuring more than weighing, and some with weighing more than measuring—but all with both of these processes to a greater or less degree. Methods of weighing and measuring have improved constantly from the earliest times and have kept pace with the advance of other technical processes. It is, therefore, believed that you will be interested in a few remarks concerning some of the more recent advances in relation to the establishment of decimal standards of length and mass in this country. Before speaking of this, I will refer very briefly to some facts which may not be very generally known regarding our customary system of weights and measures. Although the yard is universally accepted as the unit of length, and the pound as the unit of mass, it is not generally understood, I believe, just in what respect the yard is the unit of length, or the pound the unit of mass. That is to say, it is not generally known in what degree these units have been legalized by Acts of congress. Doubtless, many of you are familiar with the facts which I will briefly recapitulate. The Constitution of the United States authorizes Congress to establish a system of weights, measures and coinage. The establishment of a system of coinage, as you know, was one of the first acts of the government, and the system then adopted is certainly one of the most perfect, if not the most perfect, that the world has yet seen. But, although Congress had the power to establish a system of weights and measures, it has never yet seen fit to exercise this power; that is to say, Congress has never yet

Jan 1, 1890

By F. H. McDowell

About a year ago Dr. Raymond, as engineer of Messrs. Cooper, Hewitt & Co., together with Mr. Rothwell, was considering the removal of the ore-floors and pillars from the Peters Mine at Ringwood, N. J., where the limit of profitable working by the old method of mining had been very nearly reached. Mr. Ferdinand Ruttmann was engaged to make the survey which forms the basis of the accompanying diagrams. At first it was thought that some method of mining and filling might be introduced with advantage; but after a careful study of the operations at the Tilly Foster it was decided to adopt the system of stripping.

Jan 1, 1890

By F. P. Dewey

Recent discussions have furnished to the members of the Institute much information concerning aluminum and its applications. The present paper will be devoted almost entirely to the description of a process by which the metal is produced in the form of alloys. The characters which especially distinguish the Heroult process consist in electrolyzing a mass of molten alumina (Al2O3), and at the same time alloying the separated aluminum with a heavy metal, the heat necessary for the fusion of both the alumina and the alloying metal being supplied by the direct passage through the molten Al2 0, of an electric current of high amperage and low voltage. The process has been in active operation at Neuhausen in Switzerland for about two years. It is also in active operation at Froges in southern France. Both these locations were selected for this purpose on account of the presence of large and desirable water-powers. The apparatus consists of a carbon containing-vessel, which may be a single crucible for small operations, or may be built up of slabs or blocks of carbon for large and industrial operations. When built up of slabs or blocks, the whole is surrounded by an iron casing. In the earlier crucibles this iron casing was cast around the carbon, in order to secure close electrical contact. This, however, has been found unnecessary; and in the later crucibles the casings consist of plates bolted together, while pulverized carbon is packed between the carbon blocks and the iron. Electric conductors are united direct to this iron casing, and the current passes from this through the carbon lining to the interior of the crucible. By this

Jan 1, 1890

By B. F. Fackenthal

One of the practical questions presented to the blast-furnace manager, with regard to which little help can be obtained from existing technical literature, is the manner of filling and blowing-in. This operation is often performed according, more or less, to traditions which have come down from earlier practice, and which, if not positively detrimental when followed with the large modern furnace, may at least be greatly improved, just as the running of the furnace itself, while in blast, has been improved. It is not necessary, as many of the old furnace-men believed, to make a lot of white or silver-gray iron at the start, or to spend many weeks, or months even, in bringing the furnace to its normal burden. It has seemed to me that the publication of carefully-recorded data of practice on this point may be interesting to the members of the Institute engaged in the management of blast-furnaces. The enlarged blast-furnace at the Durham Iron Works, Riegelsville, Pa., owned by Messrs. Cooper & Hewitt, of New York City, was first put in blast February 21, 1876, since which time it has made seven blasts, and is now running on the eighth. A description of the furnace-plant, together with a record of the fifth blast, was given in my paper read at the Chattanooga meeting, May, 1885 (Transactions, xiv., 130). After some of the early blasts the furnace-lines underwent considerable change, and I have thought best to accompany this paper with drawings showing the lines and the tuyere-arrangement (see Plates I. and II.), and to give also the following summary of the conditions and results of each blast. During the first and second blasts no coke was used, and the furnace ran very irregularly, showing a constant tendency to scaffold, which was attributed, in great part, to the small hearth and other defective lines. The large proportion of air required at this furnace is accounted for by the fact that the engines are defective, and do not deliver into the furnace the amount of air indicated by the pistondisplacement.

Jan 1, 1890

By W. H. Adams

Inasmuch as] the mining of phosphate rock and its transportation has so general a bearing on the great industries of this continent, entering as well into the problem of our trade with foreign countries, it may be useful to place on record the following list of localities from which certain products of a like nature are received by us in a business way, or in which we are interested more or less either by ownership or by competition. As a ready means of comparison, the percentages of the mine products and the deteriorating constituents are given : Coprolite (Cambridge).—This material is obtained from the Upper Greensand formation in Cambridgeshire. The phosphate runs from 50 to 60 per cent., and averages 64 per cent. It contains much carbonate of calcium, but little iron, in the ferric condition. The superphosphates manufactured from the material are permanent and little liable to a revert." They contain from 28 to 35 per cent. of soluble phosphate. Coprolite (Buckingham).—From the same formation as the Cambridge variety, and very similar in composition.. It averages 60 per cent. phosphate. Coprolite (Suffolk).—These coprolites are not so valuable for the manufacture of superphosphate as the two previous varieties, as the iron they contain is in the ferric state, and liable to "revert" the soluble phosphate. The phosphate varies from 48 to 60 per cent., but averages 54 per cent. They are of Tertiary formation. Coprolite (Potton or Bedford).—The average amount of phosphate in these coprolites is about 50 per cent. In some cases they may, however, run up to 60 per cent., and in others may not exceed 45 per cent. They belong to the Lower Greensand formation. The ferric iron frequently is as high as 4 per cent., and the alumina as much. Russian phosphate comes from the chalk, and occurs in carious rounded masses. It contains from 28 to 35 per cent. of phosphate, but may run up to 69 or 70 per cent. Curacoa phosphate is also of very high class quality, giving 80

Jan 1, 1890

Jan 1, 1890

By William P. Blake

I have not before had the honor of offering to the Institute a communication on the subject of the variety of asphaltum which I described as uintahite; but several disconnected notices of it have appeared in the Transactions, and much additional information regirding it and its relations to other varieties of the asphalt group has been gathered together. Dr. Henry Wurtz has also discussed the nature of uintaite, and has endeavored to show that it should be considered a variety of grahamite.* We have also had an interesting paper upon."Asphalt and its Uses," from Captain F. V. Greene, containing much important technical information and a scheme of classification of the varieties of bitumen and of bituminous compounds. The object of the present paper is to bring the substance of these disconnected notices together; to present some additional facts; to revise the name uintahite; to compare the substance with the allied bitumens or asphalts, known as albertite and grahamite; and fur-

Jan 1, 1890

By Charles W. Goodale, William A. Akers

The treatment of silver-ores of too low a grade to justify either smelting or preliminary roasting, and yet not " free" enough to permit of raw amalgamation, has ever been a serious problem. As bearing upon it, the operations of the Combination Mining and Milling Company of Black Pine, Deer Lodge county, Montana, during the past year may not be without interest. It is not claimed that the process to be described is not susceptible of great improvement, nor is any claim of originality made for it; but its use is, as yet, not very general, and it seems to offer a means of profitably working the large class of partially-decomposed argentiferous ores which, by reason

Jan 1, 1890

By W. J. Keep

Some explanation of methods of testing will be given before presenting the record of a series of physical tests of aluminum, other metals and alloys. I. The Methods Employed and Meaning of Diagrams. The test-bars used, 12 inches long and 4 inch square, are cast in green sand, with chills bedded in such a way that the ends of the bar run against them. By splitting the ends of the bar the depth of chill can be measured. The chills being held in the mould 121/8 inches apart, the space between the end of the bar and the face of the chill, after both are alike cold, is the amount of shrinkage, and is recorded in thousandths of an inch per foot.

Jan 1, 1890

By S. F. Emmons

Introductoy.—In view of the fact that an opportunity is to be offered to the members of the Institute present to inspect the recent developments of gold-deposits in the immediate vicinity of Washington it has seemed appropriate that some preliminary description of them should be given which may facilitate that inspection. It would have been a matter of much satisfaction to me to be able to present some general description of the gold-deposits of the Appalachian system ; but I have as yet had no opportunity of personally examining any others than those of Montgomery county, and these are still in their infancy. It is, moreover, a slower and more difficult operation to make geological observations in this region than in the more northern States; for whereas in the latter region the

Jan 1, 1890

By W. H. Furlonge

WHILE fulfilling professional engagements, my travels over this portion of the Transvaal have been quite extensive—always on horseback however, so that anything like a thorough investigation of the ground passed over has been necessarily impossible; still, the more minute examination of certain small areas, coupled with general observations, has enabled me to form some idea as to the prominent geological features of the country as a whole. Anything like a complete or comprehensive description is indeed out of the question, as there are no proper maps of the country and the facilities for observation are limited. A large plateau, called the "High Veldt," stretches from east to west across the Transvaal. It is generally level, or gently rolling, and has an average elevation of 6000 feet above the sea; it is destitute of timber, and in fact greatly resembles the western prairies of North America. Rock-outcrops are not common in it. It terminates very abruptly to the east and northeast, the descent of 2000 or 3000 feet into the mountainous country that occupies its borders being made in a

Jan 1, 1890

By Willard Ide Pierce

THE native methods of mining and milling gold-ores in Korea may not present any specially new features, but are chiefly interesting as primitive practices, still followed at the present day. In mining where the rock is hard, wood is piled up near the face of the tunnel or drift and then set on fire. The fire bums for twenty-four hours, after which, three or four days are given for the rocks to cool, before the miners go in and extract the loosened material. The only tools in use are a hammer, a steel gad about five inches long, and a flat spoon-shaped basket. The pay-streak or chute is closely followed, and in places the workings are very small and intricate. Rock not yielding more than $6 per ton is not extracted. The manner of opening a mine is to begin on the outcrop, where the rock pays, sink a shaft or run a tunnel on the vein, and follow the pay-streak and more easily worked ore. When this is exhausted, or the influx of water interferes, the opening is abandoned and operations are begun again at a new spot on the outcrop. The place usually selected is as high up on the mountain as possible, and in no instance is advantage taken of the topography by running a cross-tunnel to tap the vein. The ore is brought in baskets to the surface, and there placed in sacks, holding about 150 1bs. each, and taken to be crushed. The rock is first crushed between two stones, as shown in Fig. 1. The upper stone is oval and rounded on the bottom, so that it can be readily rocked on the under stone. Two pieces of wood, used for handles, are placed, one on each side, in grooves in the upper stone, and held in position by means of straw rope. The lower stone is not smooth on top, but exhibits three elevations running lengthwise, with shallow depressions between them. The middle elevation acts as a fulcrum on which the upper stone may be rocked. From two to ten men, according to the weight and size of the stone used, are employed in rocking. With four men, from 300 to 350 lbs. of rock can be crushed per day, the stone making 50 complete oscillations per minute. The men squat on each side of the stone and move it to and fro by means of the wooden handles. The ore is fed, in pieces up to the size of an egg or even larger, by one of the men. During the crushing one man on each side, as the stone rocks from

Jan 1, 1890