Search Documents

By Bertrand S. Summers

The technologist who has devoted much attention to the foundry-business will perhaps have noticed that the present scientific development of foundry-practice is in a condition similar to that of the steel-business some twenty years ago. In many cases chemistry is looked upon with suspicion, and the old cutand-try-methods are still in vogue, especially in the smaller foundries. The larger works have laboratories and more extensive means for applying science, and have devoted considerable time and attention to the improvement of foundry-practice. This is more especially true in the East, although in the West there are numerous firms devoting considerable attention to improving their metllods through the application of chemistry to work in the iron-foundry. It is hardly necessary to dwell extensively upon the effects of the different metalloids associated with iron, in pig- or castiron, in the way they are given in most text-books. The writer has thought proper to consider more particularly new developments in eupola-practice, particularly those pertinent to the discussion of the physics of cast-iron. In this connection some new ideas which recent practice has developed will be mentioned, and some results of practical tests along the same line will be described. Yet it has been deemed advisable also, by way of introduction, to outline the effects of the metalloids as they are described in most text-books, without going into detail. The question is sometimes asked, What is the most important element governing the quality of cast-iron 'for any particular purpose ? It would seem that right here lies the basis for the greatest difference of opinion. Some twenty years or more ago, silicon was regarded by foundrymen as one of their worst

Jan 1, 1899

L. S. Austin, Denver, Colo. (communication to the Secretary) : Mr Hartman says (p. 4 of the pamphlet) that the penetration of air into the crucible of the blast-furnace " is, of course, a function of the diameter of the nozzle." To this I would emphatically take exception. Fig. 1 represents a vertical ideal section of tuyere, cruciblewalls and charge, immediately at the tuyere, in which the currents of air are represented, both in quantity and in direction, by the tortuous black-lines emanating from the nozzle-opening and passing through channels of the least resistance. As an electric current, flowing by various conductors to a common point, is carried in quantity inversely as the resistance of those conductors, so here the air ramifies through the most open cavities or channels, relatively little of it passing where the resistance due to fine materials is great. This figure represents the course of currents in the vertical plane only. As a matter of fact, they pass away in every plane, as opportunity offers. The effect of blocking or decreasing the area of the nozzleopening would certainly only decrease the quantity of air entering by that particular tuyere, without assisting penetration. The large channels (b, b, Fig. 1, for example) would still carry the larger part of the air, while again the smaller channels (a, a, a) would continue small and take no larger percentage of the air than before. These channels momentarily change, however, with the slow descent of the coke. Further on (p. 5), Mr. Hartman describes the dispersive effect of a single lump of fuel. He has only to conceive the entire spaces before the tuyere-nozzles as filled with such lumps, in order to parallel the condition of affairs I have just explained. It is where the large pieces of the charge come down, that the mass is the most open, and the blast passes most freely. On the other hand, wherever the fine ore collects combustion proceeds slowly, because of the smaller supply of air. The

Jan 1, 1899

Jan 1, 1899

By R. W. Raymond

Through the courtesy of Mr. James H. Mayo, a member of the Institute, who is in charge of the operations of the Mindrinetti Company in the Saramacca district of Dutch Guiana, I have received specimeris of certain peculiar pseudomorphs of limonite after pyrite, which occur abundantly in the auriferous deposits of that. region.* I am indebted to Mr. H. Tweddle, a geiltleman- connected with the same company, for some particulars of interest con-

Jan 1, 1899

By Edward Keller

About a dozen years ago the art of bessemerizing copper- * matte, brought to these shores from France, was first established at the smelter, in Butte, Montana, of the Parrot Silver and Copper Company, which had bought the process from Mr. Manhks, the inventor. Through the efforts of Mr. J. E. Gaylord, general manager, and Mr. A. J. Schumacher, snperintendent,, assisted by an able staff, the new method rapidly underwent, at the Parrot establishment, an evolution towards higher perfedion, and within a few years its success and its advantages were so marked that all the great works in the west followed in the footsteps of this pioneer. The converter-process has now practically superseded the reverberatory-process in this country. The latter will undoubtedly, in a not very distant future, be relegated to metallurgical history. The writer has availed himself of what was perhaps the last chance to make comparisons of the two methods, working practically on the same material on an extensive scale, the reverberatory process being that of the Baltimore Copper Smelting and Rolling Company,* while the converter-process is that of the Anaconda Copper Company—both using the matte from the latter company's works in Anaconda, Montana. For the greater portion of the material considered in this paper, the writer is indebted to the two companies. In order to understand the difference of behavior of the several elements, and the difference of the copper produced in the two processes, it is best to study and follow those elements

Jan 1, 1899

By Henry Louis

The object of the present paper is to call attention briefly to a novel method of analyzing the action of the ordinary gravity stamp, which has not only thrown much light upon the exact motion of the stamp-head, but promises also to be of value in determining the efficiency of a new mill before setting it to its work of crushing, and in this respect should be of service to constructors of mining machinery as well as to mining engineers. The method was devised by Mr. D. B. Morison, and developed in connection with his experiments on the comparative crushing-effects of his patent high-speed stamp and the ordinary cam-stamp, which were carried out at the works of Messrs. L. Richardson & Sons, Engineers, Hartlepool, and on which he read a paper at Newcastle in 1897.* Mr. Morison's experiments were of a very exhaustive nature; and having been consulted by him during his investigations, I had frequent opportunities of examining the methods employed and the results obtained. Experiments were first made with an apparatus resembling the indicntor of a steam-engine, inasniuch as the drum revolved alternately backwards and forwards, thus producing a closed diagram. This form was not found satisfactory, and it was therefore altered so as to cause the drum to revolve continuously in one direction, thus giving a continuous or open diagram. The arrangement is shown in plan in Fig. 1; a collar, A, surrounds the stamp-stem loosely and works between the guides B, B, which constrain it to move in a vertical line only. Immediately above it and below it, a couple of collars are clamped to the stamp-stem, so that the latter, while free to revolve,

Jan 1, 1899

By Gifford Pinchot

The proposition that forest reserves are, from the mining point of view, not only desirable but necessary, is not one which would have received enthusiastic support in. the West a year ago. It is, nevertheless, easily susceptible of proof. A short and simple statement of the facts has seldom failed to carry conviction as to the wisdom of the forest-reservation policy. Hostility to mining interests was never contemplated by the men to whom the forest reserves are chiefly due, and it is most unfortunate that the opposite belief should have obtained wide

Jan 1, 1899

By Charles C. Upham

Not long ago a few acres of coal-land in the Connellsville region of Pennsylvania were sold at the rate of $1500 per acre. While this was doubtless a " fancy " price, affected by some consideration other than that of the simple value of the coal in the tract. it may fairly be taken as an indication of a progressive and already perceptible diminution in the economically available coal-resources of that famous region. This piesent and prospective development emphasizes the cominercial importance of producing, from the inferior coals of other districts, coke suitable for use in the blast-furnace. Many of the bituminous coals of the United States would meet this requirement if sufficiently freed, before coking, from slate and sulphur, and, so far as the removal of slate is concerned, the problem is not specially difficult. There are many forms of trough-, jig- and gravity-washers which easily and cheaply reduce the slate from as much as 20 per cent. in the coal to as little as 8 per cent. in the coke. But to reduce the sulphur from 4 per cent. in the coal (a proportion sometimes encountered) to 1 per cent. or less in the coke (the proportion demanded by the furnace-manager) is not so easy. It may be safely assumed as familiarly known to members of the Institute interested in this subject that, of the three forms in which sulphur usually exists in coal (hydrogen sulphide, calcium sulphate and pyrite), the pyrite is the one to be removed, RS far as possible, by mechanical treatment before coking. Hydrogen sulphide, being volatile, is expelled in

Jan 1, 1899

By Persifor Frazer

From the easternmost point reached by the Ural excursion of the VIIth International Geological Congress (the city of Tschéliabinsk, a little more than 30' of longitude east of St.

Jan 1, 1899

Jan 1, 1899

By W. C. Ralston

This note will give the cost of driving an adit at the Melones mine, in 1898, and, for purposes of comparison, the cost of similar work, in 1888, at the Hogsback mine, Placer county, Cal. The property of the Melones Consolidated Mining Company is situated on the Mother Lode of California, on Carson Hill, near Robinson's Ferry, and adjoins on the south the famous Morgan mine. The Mother Lode of California extends for a distance of over 100 miles in length through several counties, with a general strike of northwest and southeast. Three veins (commonly called the east vein, middle vein and west vein) comprise the " lode " in this section. The Melones property is situated upon the east and middle vein, and includes 1407 feet on the east vein and 5166 feet upon the middle vein. A shaft had been sunk on the Reserve mine, which is on the east rein, and within 230 feet of the Morgan mine. At the bottom of this shaft drifts and cross-cuts had been run and a large body of ore developed. It was deemed advisable by the Melones Mining Co., which holds this property under bond from the Melones Consolidated Mining Co., to run a tunnel and develop this body of ore at a greater depth. An option was obtained upon the South Carolina mine, which adjoins the property on the south, and is on the same east vein, upon which a tunnel had been run a distance of 1080 feet. This tunnel was cleaned out and continued to a point within forty feet of the Morgan mine. It passes directly under the Reserve shaft, 425 feet below the 200-foot level. The additional length of tunnel to be run was 1923 feet, and

Jan 1, 1899

By George J. Bancroft

Western Australia (often popularly called Westralia) comprises all of the Australian continent west of the 129th meridian. The latest census, that of 1895, gives it a population of 101,235 persons. It includes within its bouiidaries 975,920 square miles. About half the colony lies within the tropics. The climate varies but slightly, considering the vastuess of' the area. The interior is dry and hot, and subject to very sudden changes. The coasts are warm, and the rainfall abundant, varying from 20 to 40 inches per annum. Perth is the capital and principal town, having a population of 20,000. Fremantle (pop. 9000), distant 12 miles, is the port of Perth, but because it is out of the track of the mail steamers, the mail and passengers are landed at Albany (pop. 3000) on St. George's Sound. A railroad, 338 miles long, connects Pert11 with Albany, and the running time of trains is about fifteen hours. Kalgoorlie is only about 200 miles from the coast at the little village of Esperance; but to reach Kalgoorlie one must land at Albany, travel to Northam, within 66 miles of Perth, and then east at an acute angle 325 miles to Kalgoorlie; in all about 600 miles. From Perth a railroad also runs to the Murchison gold-fields by way of Mingenew, Mnllewa and Yalgoo, to Cue. A branch goes down to the port of Geraldton. The government operates all the railroads and telegraph lines, and has been very energetic, all things considered, in extending them into the gold-fields. As to the accommodations afforded by the railroads, the less said the better. The comforts of travel are conspicuous by their absence. Of the 975,920 square miles of Westralia, the government, in its magnificent way, cleclares 256,060 to be gold-bearing. There are the Kimberley fields in the north, of 47,000 square miles; the Pilbarra on the northwest coast, of 45,600 square

Jan 1, 1899

Jan 1, 1899

By R. W. Raymond

GEHEIMER BERGRATH Prof. Dr. HIERONYMUS THEODOR RICHTER, ex-Director of the Freiberg Mining Academy and Honorary Member of this Institute (to give him the full title, which nobody ever thought of using in his genial and unceremonious presence, and the whole of which I have omitted at the head of this notice, as adding nothing to the virtue and value of the man I knew), died on Sunday, September 25,1898. He was born in 1825 at Dresden, and in 1843, after some practical training in pharmacy, entered the Freiberg Mining Academy, where he devoted himself chiefly to metallurgy and metallurgical chemistry, under the guidance of the celebrated Plattner, whose masterly instruction in those arts, and also, especially, in assaying and the use of the blow-pipe, has been classic authority to the present day. In 1853, Richter was ap-

Jan 1, 1899

Jan 1, 1899

E. W. Parker, Washington, D. C.: In connection with Mr. Blauvelt's paper, a brief sketch of the development of by-product coke-making in the United States may prove of interest. The first radical departure from the prevalent beehive oven to the by-product retort oven was inaugurated in 1891 by the Solvay Process Company, at Syracuse, N. Y. In that year was begun the construction of 12 Semet-Solvay ovens, which were completed in 1893. During 1893 these ovens produced 12,850 tons of coke, an average.of a little over 1000 tons each. In the following year the production amounted to 16,500 tons, not quite 1400 tons per oven. These 12 ovens were in reality an experiment, the success of which was attested by the addition to the same plant of 13 more ovens, begun in 1895 and completed in 1896. They were followed by the construction in 1896 of 25 ovens of the same type at Sharon, Pa., and 50 more at Dunbar, Pa. These 100 ovens represented the total number of Semet-Solvay ovens completed and in operation up to the close of 1897. The construction of 180 more, however—120 at Ensley, Ala., and 60 at Benwood, near Wheeling, W. Va.—was begun in 1897. The plant for the latter is laid out for double the number stated. The 60 ovens begun in 1897 have now been completed. An initial plant of Otto-Hoffman ovens was built at Johnstown, Pa., in 1895, and began making coke in 1896. One hundred and twenty additional ovens of this type were begun in 1896 and completed in 1897 at Glassport, near McKeesport, Pa. During the present year 100 Otto-Hoffman ovens are being added to the plant at Johnstown, and 400 of the same type are in course of construction at Everett, near Boston, Mass. The plant at the latter place is laid out for a total of 1200 ovens.

Jan 1, 1899

Jan 1, 1899

mean to say that these explosions are mechanical, but that the ejectment of the stock, throwing out of tops, etc., are mechanical. I see no reason at present, although I have had almost no experience in the use of large quantities of Mesabi ore, to change my ideas on the subject. That these explosions should follow irregular working or slipping in the furnace, I think can be explained. I have noticed that immediately following slips there is little or no settling of the stock on top, although there is no lessening of the volume of gas passing into the stoves and boilers. Supposing that, after a slip of 3 or 4 feet, the filling continues, but for some distance from the 'top the stock fails to move: there would be a much better chance for the deposited carbon to clog interstices in the stock, and for the additional effect in the same direction of the fine ore in the charge, than if the stock were properly settling. Under such conditions it is easily supposable that the openings would be entirely closed, or closed so tightly that the pressure below the obstruction would be raised to a point approaching the blast-pressure, or to a point high enough to force a passage or an enlargement of the small passages which may remain. When this occurs, gas from below under pressure carries with it large quantities of deposited carbon and fine ore; if the case is aggravated, coke, stone, bell, etc. As soon as the red-hot deposited carbon meets the air there are perfect conditions for a dust explosion, which naturally follows, the same as in a coal-mine or flour-mill.

Jan 1, 1899

Edgar Hall, Tenterfield, New South Wales (communication to the Secretary): Mr. Klepetko* asks for information showing at what percentage antimony and arsenic, as impurities, begin to affect injuriously the quality of brass.

Jan 1, 1899

Charles H. Morgan, Worcester, Mass. (communication to the Secretary): In connection with Mr. Douglas's mention of the continuous charcoal kiln used at Kopparberg, some further data concerning this important invention may be of interest. Before giving these, however, I will say a word or two concerning other features of Swedish practice. In 1894 I spent two days at Soderfers with Mr. Tom Bergendal, the manager of the works, and was specially interested in the gas-producers and wood-drying kiln, illustrated in the paper contributed to our Transactions by Mr. Odelstjerna in that year.* The wood-drying kiln is, however, quite different in design and construction from Ljungberg's charcoal kiln. In the summer of 1894 it was discovered that by placing the gas-producer as close as possible to the open-hearth furnace, and working the producer hot, ordinary weather-dried wood, still containing a considerable percentage of moisture, could be used to advantage in the melting-furnace. Hence, the dryingkiln was needed for wet wood only. One of the iron-works of the Udeholm Go. was the first to adopt the Lundin saw-dust gas-producer and condenser, enabling them to make gas from saw-dust containing 45 per cent. of moisture, and convey the gas from the condenser through wooden pipes to the Siemens steel-melting furnace.† This sawdust gas gave very satisfactory results in iron-works; but the proprietors experienced much trouble by reason of the pollution of rivers by the tar-water from the condenser. On my visit, in 1894,I found that the Udeholm Co. had put in for their steel-melting furnaces the same wood-gas producers

Jan 1, 1899