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By Robert Anderson Cook

AS the margin of profit in the manufacture of iron continues to decrease, attention is called more and more to economies in every department. Beginning at the bottom, in the preparation of the ore at the mine, me notice a general tendency is towards the shipment of richer ores, securing to the mine-owner a better price per ton, which the purchaser is glad to pay by reason of the saving in freight of iron, and in the cost of reduction, which depends so largely upon the amount of fuel and flux, and the productive capacity of the plant. In other words, the difference in value between rich and poor ores is much greater than their relative percentages of iron indicates; because the barren material in a lean ore is not merely worthless, it is a positive source of expense, requiring transportation, handling, fluxing, smelting, and its due share of general expenses; in return for which it yields nothing and decreases the available capacity of a given plant and capital for profitable work. The enriching of the ore is done in most places by hand-picking, and in a few by wet concentration; but the managers of several magnetite mines in Sweden have been practically successful in doing it by machinery. The only magnetic separating machine which has actually taken the place of hand-picking was designed and patented by Mr. Jonas Wenström of Örebrö, Sweden. In this machine, which is illustrated in Figs. 1 and 2, Mr. Wenström has taken advantage of the property of soft iron to become magnetized by induction. The machine consists of a barrel made up of soft iron bars and some non-conducting material (usually wood), which is rotated around a stationary shaft by means of a cog-wheel. Inside of this barrel, on the shaft, is placed eccentrically a cylindrical electro-magnet, provided with a number of manges (N, S, Fig. I), between which wire is wound in such a manner that the flanges are of negative and positive polarity, being energized by a current passing through the wire coils from a small dynamo. As will be seen in Fig. 1, the flanges, N, S, are circular, and follow the internal contour of the barrel on the front side, while on the opposite side they are cut down to the line B, B' in Fig. 2. Hence the bars of the revolving barrel on the front side of the machine are mag-

Jan 1, 1889

Jan 1, 1889

By Ellison C. Means

Many Virginia furnaces are troubled with a small percentage of zinc in their stock, this element being present, although the chemist may have failed to report it, either in the ore or in the limestone.

Jan 1, 1889

By J. M. Silliman

Several years ago, having occasion to determine the amount of some very slight atmospheric depressions, I devised and had constructed by a skilful tinsmith the manometer shown in the accompanying drawing. It consists of a cylindrical vessel of tin, 6.6 inches in diameter, through the sides of which, at a distance of about six inches from the top, passes an air-tube D, its upper extremity terminating 3.5 inches from the top. Within the vessel is a combined cylipdrical

Jan 1, 1889

By William Hamilton Merritt

A brief paper on this subject (which might readily be made to, fill a volume) is suggested at this time by several considerations, among which may he named the meeting of the Institute on the borders of Ontario, not far from some of the mining undertakings which are hereafter mentioned ; the mineral developments made in the Province quite recently ; the highly creditable collection of most of the minerals of Ontario, for the first time got together, and exhibited this year at Cincinnati, in the Centennial Exhibition of the Ohio Valley ; and, finally, the recent appointment, by the Government of Ontario, of a Commiesion to inquire into, and report upon the mineral resources of the Province, and the best means to be adopted for their development. The Province of Ontario has no Department of Mines or official geologist, to take note, and keep record, of mining and mineralogical development and discovery. Within the last few years some valuable statistics have been collected by Mr. A. Blue, the Deputy Minister of Agriculture; but recently a desire has risen on the part of the people to obtain further knowledge of these subjects, and the government has appointed a Commission, the report of which is expected to be issued in part, if not in completed form, this winter.

Jan 1, 1889

By Oberlin Smith

It may surprise the learned metallurgists who read this paper to learn that, by a recent discovery, nails of good quality can be made at one operation, directly from the ore, at the rate of, say, sixty per minute for each operator. It should be stated, however, that the raw material referred to does not answer strictly the ordinary assayer's definition of' an ore. It is found, in strata of various thickness, in Harlem, N. Y., and other localities where the débris from restaurants and from sheet-metal factories of various kinds has been dumped. In other words, it is old and new tin-scrap—one of the few substances which this generation, mainly occupied in exhausting the accumulated resources of the past, seems to have laid up, by way of atonement, for the benefit of posterity. In speaking of this material as ore, we are simply looking forward, prophetically, to the time when our descendants may dig it. up and write learned papers for the American Institute of Mining Engineers upon the best methods of assaying and smelting it. At least such has seemed to be its destiny hitherto. It may fairly be said that the many attempts which have been made to utilize it by separating, through chemical or electrolytical processes, its two valuable constituents, metallic tin and first-class wroughtiron, have failed, either technicaljy or commercially. The reasons fur such failure need not here be discussed: Either the separation has been incomplete, the iron still retaining enough tin to spoil it for the sinking-fire, or other use short of re-melting (perhaps even for that), or the manipulations of the process have been too expensive to make its results profitable—or both. Meanwhile the great tin-scrap deposits have gone on growing faster than any other strata of our Post-Tertiary, Psychical Era; given up by metallurgists, not yet attacked by geologists, and explored only by that mining engineer of the transitional period, Gulielmus Caper. Before leaving these heaps of tin-scrap, however, to become mere mineral deposits for future ages, it may be well to consider a novel plan for their immediate utilization—novel, not only in its means, but in its principle. For it undertakes to use this material just as it is, without trying to separate its constituents at all, and to use it,

Jan 1, 1889

By B. F. Fackenthal

For the past year we have had in use at the Durham furnace a set of hollow pig-patterns made of iron, which have given such satis factory results that I think a description of them would be of interest to the members of the Institute. Before the introduction of these iron patterns, we used the ordi nary wooden patterns, made in the usual way with straps of iron along the sides to protect the corners from wearing off. The size and shape of these wooden patterns are shown in Fig. 1. When the patterns were new, the pigs weighed about 130 pounds each, and were uniform in size, and the moulding was clean. But constant use soon wore the patterns away; and at the end of a few months, the pigs had become, in consequence, so much lighter that the moulding, daily, of several additional beds was necessary to accommodate the same quantity of iron. As the patterns wear away, the moulding becomes ragged and the pigs rough. Moreover, wooden patterns are often destroyed by fire. I have known an entire set to be destroyed by a break-out of iron. The iron pattern which I have designed is free from all the objections to the wooden pattern, being not only more durable, but, in the long run, far cheaper. The iron pattern having the same shape and size as the wooden one, is made of the best flange-iron, of No. 13 gauge. After the sheets have been cut to the proper size, three heats are required for the flanging. At the first heat, each piece is stamped in a cast-iron form, which gives the proper shape to the bottom part of the pat-

Jan 1, 1889

Jan 1, 1889

By Arnold Hague

In the short time allotted to me* I can only hope to present to you a brief sketch of the main geological features of the country which you are about to visit. My remarks must, of necessity, be more or less incomplete, as my desire is not so much to elucidate any special problem connected with the many interesting geological questions to be found here, as rather to offer such a general view of the region as will enable you, during your five days' trip through the Park, to understand clearly something of its physical geography and geology. The Yellowstone Park is situated in the extreme northwestern portion of the Territory of Wyoming. Its boundaries, as determined by the original Act of Congress setting apart the Park, are very ill-defined. At the time of the enactment of the law establishing this national reservation, the region had been but little explored, and its relation to the physical features of the adjacent country was but little understood. Since that time, surveys have shown that only a narrow strip, about two miles in width, was situated in the Territory of Montana, but it was also found that a still narrower strip extended westward into the Territory of Idaho. The question of properly establishing the boundaries, -based upon our present knowledge of the country, is now before Congress, and an Act has already passed the Senate, proposing to make the northern boundary coincide with the boundary between Wyoming and Montana, and the western boundary coincide with the Wyoming and Idaho line. The Act under consideration extends the southern boundary of the Park to the 44th parallel of latitude, carrying the area of the reservation southward nine and one-half miles. The eastern boundary is made to coincide with the meridian of 109' 30') adding a strip of country about twenty-four and one-half miles in width along the entire eastern side of the Park.

Jan 1, 1888

Jan 1, 1888

Jan 1, 1888

By F. F. Claussen

The method of making silver ingots in use at this Mint being radically different from that employed at any other Mint of the United States or, so far as known to me, any Mint in the world, there may be some interest in a description of the apparatus used and a brief history of its distinguishing feature, viz., the rotary ingotmould, which, though not a recent improvement, is comparatively unknown. The furnaces used for silver-ingot-melting are four in number and have a capacity of some seventy thousand standard ounces of silver per day of eight hours. This output is increased, when the exigencies of the service demand it, to one hundred thousand ounces. They are built of fire-brick and elevated 21/2 feet from the floor of the melting-room, in order to have space to place iron boxes and to work, in case a crucible breaks in the furnace and its contents run into the ash-pit. The furnaces are circular in horizontal section, 2 $ feet in diameter and 29 feet high inside in the clear, and rest on castiron plates, with top-plates of the same, and sides encased in boileriron. The furnace-covers are also of cast-iron, dome-shaped, and are handled by means of a small crane and lever. The furnaces stand in sets of two, and one crane and one ingot-machine serves two furnaces. The crucibles used are made specially for this purpose of a mixture of black-lead and fire-clay; the size known as No. 200 will contain and safely melt, without danger of slopping over, from 8600 to nearly 10,000 ounces of standard silver; and this is the usual weight of the ingot-melt at this Mint, as against 1800 ounces at the Carson City mint and 2600 to 3000 ounces at Philadelphia and San Francisco. Each crucible will endure, on the average, ten melts. The crucible stands in the center of the furnace, on the bottom of an old one, cut down to a height of about three inches. The fuel used is coke. Experience has shown that, notwithstanding the higher first cost, Connellsville coke is cheaper than Alabama coke and much more suitable to the work. A small triangular black-

Jan 1, 1888

By Alfred E. Hunt

The late Alexander Holley said, on returning from a careful study of the relative merits of the Bessemer and the open-hearth processes, as shown in the best European practice, that, in this country, the open-hearth process would live to attend the funeral of the Bessemer ; and he said this several years ago, when in this country the Bessemer plant and practice had been developed to far outstrip that abroad, and when, proportionately, it had reached an advancement much beyond the improvements in open-hearth plants and practice. At the same time, the prevailing idea in the metallurgical world, a few years ago, seemed to be in favor of the substitution of Bessemer for open-hearth steel for most of the higher qualities, and Bessemer enthusiasts loudly proclaimed, that as good steel for all purposes could be obtained by their favorite process as by the open-hearth. It was, in fact, confidently prophesied that very soon tool-steel and similar grades, which consumers had learned to specify, in ordering, to be made by the crucible process, would by common consent be made by the Bessemer, as best adapted to give the desired results. But these expectations have failed to materialize; not only do the crucible people keep on in the even tenor of their way and talk with pride of their comparatively large outputs of " hundreds " of tons per month, as usual, but the open-hearth people have kept fast hold of their original domain of nearly the entire amount of sheared plates, of locomotive tires, of large forgings, spring-steel, agricultural steel, steel castings and the like. Further, owing largely to one of the great advantages of the Bessemer process, which is also one of its inherent dangers, namely, its large output, it has also fallen into considerable disrepute for structural purposes. Not a few experienced engineers are now stipulating in their specifications that Bessemer steel will not be allowed to be used, especially for tension-members.

Jan 1, 1888

By Charles A. Ashburner

A very limited development has been made of the coal-fields of this Territory. This is to be accounted for by the fact that a number of the coal-fields lack railroad transportation, by the distance of other fields from the consumers (due to restricted settlements), and finally by the poorer quality of a number of coals which have been mined as compared to others which can be economically imported into the Territory. The consumption of coal in Utah during 1886, outside of that used by the railway companies, was: Tons. Utah coal,..........110,000 Wyoming coal,. .....19,000 Colorado coal,........* 4,945 Total,........... 133,945 It is estimated that there are 1100 miles of railroads in the Territory which use coal for fuel. The consumption of these roads for the year is estimated at 100,000 tons, making an aggregate consumption in the Territory of 223,945 tons. The consumption of coal in Salt Lake City duriug the year was as follows: Tone. From Grass Creek mines,.......21,000 " Pleasant Valley Company's mines,.. 12,700 " Utah Central Company's mines,.9,000 " Bock Spring mines,.6,500 " Almy mines .. ., .. .. . 6,000 " Miscellaneous sources,..5,800 Total ,.........60,000

Jan 1, 1888

By J. C. Bayles

It is seldom the privilege of one who contributes to the Transactions of a technical society, to describe a new industry in which, by processes employed for the first time, are attained results of conspicuous value. There are but few such patches of virgin soil worth the tilling, within the area circumscribed by the industries which have experienced a regular and uniform development. New and startling methods in production are often announced as about to be introduced; but, as a rule, they take their place among the " large desires with most uncertain issues," or give new significance to the historic words of an eminent statesman concerning " the bright beginnings and the bitter end of a halcyon and vociferous proceeding." In this paper I shall have the pleasure of briefly describing a new industry which has been established without announcement or proclamation — the manufacture of serviceable pressure pipes of great strength, from strips of steel or iron wound spirally, heated only along the overlapping edges, welded by hammering and finished into tubes of uniform diameter, and of such length as mag be found convenient in handling and transportation. As such tubes are now manufactured on a considerable scale, in a range of sizes which will soon include everything between 4 inches and 30 inches, and as much larger as may be needed, both process and product are likely to be of interest to engineers in all departments of professional work. The raw material of the industry is the ordinary sheet-iron or steel of commerce, of such lengths and widths as it is convenient to roll. The range of the ganges of the metal which can be employed has riot yet been determined. The lightest metal thus far successfully made into pipe is No. 29 iron, and the heaviest a steel gauging somewhere between 12 and 14. Heavier machines are now building which will bend steel .165 of an inch in thickness, or No. 8 of' the Birmingham gauge. Probably No. 20 or No. 22 will be the lightest used in making commercial pipes; hut the experiment with No. 29 was interesting as showing the readiness with which the flame can be controlled. To get a welding heat with such thin

Jan 1, 1888

By Robert H. Richards, Richard W. Lodge

A great deal of speculation, as well as actual experiment, has been devoted to ascertaining the changes in the materials (luring their descent in an iron blast-furnace, affecting (1) the chemical constitution, (2) the mechanical condition, and (3) the arrangement of the materials. With a view to throw some light upon the third question, we constructed a model and tried experiments which are here described. Our model is a vertical section of a furnace, with the lines of the Edgar Thomson furnace D of 1885 for the use of which we arc indebted to Mr. Gayley. The model is 40 inches high, and made to scale (1/2 inch equals 1 foot), and the horizontal section of the space through which the charge falls at any point in the descent is 11/2 in. x d, d being the diameter of the furnace at that place. We are unable to say just where the idea of making this model came from ; perhaps, partly from The Principles of the Manufacture of Iron, and Steel, 1884, I. Lowthian Bell, p. 124 ; partly, also, from

Jan 1, 1888

By Frank Julian

The determination of manganese by precipitation with potassium chlorate from a solution in concentrated nitric acid, filtration through asbestos, and solution in a reducing agent whose excess is estimated, is open to the objections that the filtration and subsequent solution of the binoxide are apt to be very slow, and that the asbestos may (according to Troilius), unless perfectly purified, affect the titration. In the following modification, filtration is avoided. I give the method as I use it for Bessemer steel. In an 8-ounce Griffen beaker dissolve 1 gramme drillings in 15 c.c. nitric acid (1.2 sp. gr.). Evaporate to 5 c.c.; add 20 c.c. concentrated nitric acid and precipitate with chlorate as usual, avoiding a large excess; then add about 60 c.c. warm water, and 10 c.c. of the oxalic solution; stir until of a clear light yellow color, and titrate with permanganate while the solution is at about 80' C. The binoxide should dissolve immediately when the oxalate isadded. The titration is rapid, and the end-reaction, though transient, easily caught after a little practice. The standard solutions used are: 15 grammes crystallized ammonium oxalate to a liter, and 1.6 grarnmes potassium permanganate to a liter. For standardizing the permanganate, to 10 c.c. of the oxalic solution is added 50 c.c. of hot water, and a solution of 1 gratnme of steel in concentrated nitric acid, from which the manganese has been removed by potassium chlorate and filtration through asbestos. I have made a large number of determinations in steel, pig-iron,

Jan 1, 1888

By Ferdinand S. Ruttmann

There is now in use at the mines of the Chateaugay Ore and Iron Co., at Lyon Mountain, New York, an ore-concentrating machine or jig, which, in view of the increasing attention given to the subject of concentrating lean ores of iron, seems worthy of notice. This Conkling Jig, as it is called, is not entirely unknown, having been used at several places with more or less success; but as yet, I believe, no drawings of it or records of its work have found a place in print. Although the jig will be found to be merely an adaptation of old forms, there are several points which deserve attention, particularly the method of central discharge, of freeing the bearings from grit, and the rotation of the sieve or screen. The ore-body at Lyon Mountain consists of a bed of rather compact, granular magnetite, occurring in a gueiss formation. The side walls of the ore-body are not sharply defined, the ore 011 either side becoming gradually poorer as the distance from the central point of the body increases. It is this lean ore, which, before the introduction of the jigs, was thrown away as waste, that is now concentrated. The material treated conseqnently consists of magnetite, intermixed with the component parts of gneiss, viz. quartz, felspar, hornblende, and mica. Grains of trap also form part of this material. These come from dykes of trap, which cross the ore-body at intervals. The ore which is to be concentrated usually contains from 30 to 40 per cent. of metallic iron. It is first crushed to the size of two inches, or less, by two large Blake crushers. The material from these crushers passes by a shute lined with screens, having holes 2 inches in diameter, to a second set of four crushers, set so as to close to one inch. The product from this set of crushers, together with that which passes through the screens in the shute, is then taken by an elevator to the top of the mill, and passed through a revolving screen, perforated with ) inch holes. The ore which passes through the screen goes to the jig-hoppers ; that which passes over goes to a third

Jan 1, 1888

By Henry E. Colton

NeaR the town of Christiansburg, Va., occurs a singular feature in topographical as well as geological structure, which may be said to have an important bearing on a large area to the southwest. The great water-shed ridge, which divides the waters flowing into the St. Lawrence from those flowing into the Atlantic ocean, coming southwestward, forms all of what was the boundary of Maine as agreed upon by the treaty of 1783, and a part of the present boundary, all of the northern New Hampshire boundary, and entering Vermont, continues south of Lake George. Passing irregularly through New York, it enters Pennsylvania, and there bifurcating, sends one prong to the west as a divide between the waters of the lakes and the Ohio, while the other becomes the steady, regular ridge which gave it the name of Alleghany, and thus passes on southwestward through Virginia. At no point has it ever been the geological divide. Its course, commencing in the Archean rocks, has passed through nearly every series of formation, and comes into Virginia in the Carboniferous strata. The geological divide—the line between the fossiliferous and the non-fossiliferous rocks—lies, in Canada, to the west of it, but from New York south into Virginia is far to the east. Reference to Dr. Hitchcock'k map will show this. But at the locality noted these positions are changed; the water-divide becomes the eastern chain, and the geological divide is the western, returning, it may be said, to the positions occupied in the region where they originated. These relations are shown on the large map accompanying the present paper. For several miles, the track of the Norfolk and Western Railroad

Jan 1, 1888

By W. L. Austin

The only essential difference among the three methods of collecting the precious metals from their low-grade ores by fusion is comprised in the nature of the vehicle in which those metals are concentrated. If lead- or coppper-ores are used, the processes are respectively lead- or copper-smelting; but when the sulphide of iron forms the matrix in which the gold and silver are collected, the process is known as pyritic smelting. The latter method presents rarely any advantages when lead- or copper-ores are available at rates which permit profitable treatment. Pyritic silver-smelting, defined by Percy as " the smelting of silver-ores, which are either free from lead or do not contain it in sufficient quantity to collect the silver, in conjunction with pyrites, in order to produce a regulus in which the silver may be concentrated," is not, as the name would imply, confined to ores of this metal alone, but embraces auriferous silver-ores, or even gold-ores simple. This method of collecting the precious metals from lowgrade dry ores, employed at Freiberg by Barthel Kohler in 1585, does not appear, up to the present, to have been introduced into this country on a working scale. And yet the possibility of getting rid in a single operation of all the earthy or siliceous gangue of a lowgrade ore and concentrating the precious metals in a matte without loss of lead (which includes gold and silver) by slagging, or volatilization, at the same time producing a highly siliceous slag, very nearly if not quite as clean as is usual in lead-smelting, certainly commends itself. In some parts of the country, owing to the com-

Jan 1, 1888