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AN IMPORTANT PAPER ON IRON. The Magnetization of Iron Ore Considered. A Pnpcr Head by Mr. Clemens .Jonen, of lloheuduuciuii, Pa., at tlie Fall Meet? ing of the American Institute of Min? ing Knglncers at New York September, 1800. Tho peculiar property of tho lode stone has boon known for many cen? turies. It was very early observed that, by contact with it, iron is magnetized; and it is needless to dwell hero upon tho history allied to tins discovery, now constituting tho wonderful science of magnetism. Deposits of magnetic, ore are distribu? ted all over the world. The ore is some? times very rich and comparatively free from gangtic, sometimes sparsely dis? seminated in tho native rock. These bodies of loan ore often cover large areas. Modern ingenuity has utilized the principle of the magnet, originally derived from the ore itself, and really belonging to the time of IMato and Theophrastus, to separate the magnetic ore particles from the rock which lias previously been crushed. This process recovers the ore in tho state of a con? centrate very rich in iron and, in some cases, desirable for Bessemer purposes. Tho magnetic separator is no lomrcr a novelty. It was only at the last meet? ing of tho Institute in New York, that Messrs. Birkinbino and Edsion (Trans., xvii., 728) and Mr. Robert Cook (Ib., 599) described somo of tho principal de? signs of apparatus in use. E. S. Dana classifies the natural mag? netic minerals in tho following order: magnetite, pyrrohotite, franklinite, al mandite and minerals "containing con? siderable FeO." Of these, ferroso-ferric oxido, or magnetite, is tho type. The proportionate amount of ferrous oxide essential to magnetize the compound, is not established. Ferrous oxido appears to be tho only magnetic oxido of iron. Tissandier, (Compt. Rend., lxxiv.,531) produced ferrous oxido in tho anhydrous state by the action of carbon-dioxide on pure iron at a red heat, according to the equation: Fe+CO,=Fe0+C0. This is black, crystalline and mag? netic. Heated to redness in the air, it is converted into Fo ?04. Sidot (Compt. Rend., lxvii., 17,">) has also produced an oxide exhibiting mag? netic polarity, by heating ferric oxide to a, temperature not sufficient to fuse it, in an earthen tube placed in the mag? netic meridian. A. Frcnzel (Jahrb. f. Min., 1874, p. GS5) accidentally obtained small rhoni bohedra, slightly magnetic, by igniting B precipitate of ferric hydrate. The presence of ferrous oxide in mag? netite, whether as a molecular constitu? ent of the compound, or as an independ? ent molecule, seems to communicate the property of magnetism. Magnetic oxide of iron, as an artificial product, is considered to result from the direct action of carbon dioxide. In simple determinative blow-pipe work, the reducing-flame alone, or with tho aid of alkaline carbonate, produces mag? netic particles, or slag-globules, from nearly all iron-minerals. Spathic iron ores have long been known to exhibit,after roasting, magnet? ic properties?largely due, however, to the presence of metallic particles in the roasted ore. Carbon dioxide; in the ore is also here considered an important fac? tor. Of such ores, the ore-dressing at the zinc works at I'ribram, Roberaia, describe dby Mr. Ellis Clark, jr.. (Trans., ix., 451), furnishes an illustration. The principle is here used for the separation of iron oxide from zinc-blonde. "These aro separated from other ma? terial by the ordinary concentration pro? cesses, and are then in the form of a powder, the grains being less than 1 millimeter in diameter, This powder is composed of spathic iron-ore and zinc blende, and is roasted in a small oven, with froquont stirring, for an hour, when the ore is rendered sufficiently in ignetic." It is then separated by n magnetic separator, and the zinc-blcr.d ) is thus recovered. In nearly all cases of the carbonates of iron similarly treated, minute glob? ules or metallic iron are contained in the roasted oxide. Furthermore, the expulsion of the carbon dioxide con? tained in the ore. with contact of carbon at a certain beat, approximates to the conditions of tho blast furnace and favors the reduction of part of the fer? rous oxide to the metallic stal(>. The roasted carbonate is always strongly magnetic. But, from the fusible nature of the ore, it is extremely dillieult to prevent it from melting during the pro? cess, so that nearly all the associated minerals assume the form of "clinkers" ?with the ore. This circumstance, togeth? er with tho expense of crushing the ore sufliciently line, makes the magnetic sep? aration of iron oxide from thegangue ore unprofitable in such cases. At Pibram, zinc-blende is sought, and the oxide of iron is a secondary product. Hematite is sometimes magnetic, and. according to Dana, even magneti-polar ?of course, as an incidental occurrence, other than in crystallized specimens. On account of its rarity, as well as the feebleness of the attraction it presents, magnetic hematite is not available for practical purposes. Martito, tho iso metic ferric oxide which is supposed to be a pseudomorph after magnetite, is attracted by the magnet. The famous ore from Marquotte, in the Lake Su? perior region, abounds with crystals of martite. The ore from the Juragua mines, in Cuba is in part magnetic. Fayalite, FeSiOl, is magnetic. The anhydrous oxides of iron in gen? eral aro magnetic, Of all the hydrous oxidos of iron, not ono is magnetic. Brown hematite or limonito (with which gothito and turgite are usually associated), as well as the sub-varities of hydrous oxides, are non-magnetic, and havo no effect upon tho magnetic noedlo The composition of these ox? ides is: parts water. Ldmonito.2Pe4Oa+3HjO, or 14.4 ?othite.PejOa+HjO, or 10.1 "" Turgite.2Pe403+II a0, or 5.0 " " Tho importance of the brown hem? atites is indicated by tho amount of such ores consumed in the manufacture ?I iron in this country and abroad. At ?nc time- brown or? was considered in? dispensable for tho production of foundry-iron, Prior to the development of the Lake Superior hematite regions, brown hematite was the chief ore in use in America. It coours abundantly throughout Germany, "it supplies by far the greater number of Kreuch iron? workers: and it occurs also in Spain, Hussia,"(Crookes nndltohrig. Treatise on Metallurgy, p. 333) etc. In England the famed Forest of Dean supplied a great abundance of it. There are still vast bodies of tho brown varieties unworked In England, and in this country they oc? cur in nearly every State in the union. Since tho advent of the rich Lake Superior hematite-ores, hundreds of pro? ductive brown hematite ore-mines have been abandoned: and there are still numerous undeveloped beds too lean to bo handled profitably. In Pennsyl? vania the mines of Lehigh and North? ampton counties have furnished for quarter of a century the raw material of nearlv half the iron made in the Lehigh Valley. With the exception of the oolitic varieties, the localities named may bo considered to represent all of the veri? ties of brown-hematite ores. At pres? ent only the hotter grades are in use. and of these the supply is limited. An investigation of the quality, product and yield of thirty of these mines for the year 1877. undertaken hy tho writer, showed that over 100,000 tons of this ore. represented by fully 500 samples and analyses, averaged only :17 per cent, of metallic iron. Threo-quartoi'Sof this j was wash-ore.Tho bulk of this ore, which j will fairly represent the majority of this : class of mines in the United States, will carry about 34 per cent, of metallic ron in the wash-ore. Examination of the iron oxide, or ore proper, shows it to contain from -15 to 00 per cent, metallic iron, which, in the wash-ore, is, in many instances, reduced below a marketable standard by the ad mixturo of foreign material, chiefly quartz-gravel, slates and clay. Separation of tho oro is a problem presenting many-sided difficulties that have never been successfully overcome. Water-jigs and specific-gravity separa? tors of innumerable designs have been invented for tho purpose all over the world, But tho very best results with these machines fall short of obtaining tho ore entirely separated without loss in tho tailings. A concentrate carrying 43 per cent, of metallic iron is a fair economical result from theso machines, and, except with un? usually rich ores, 45 per cent, of iron is seldom obtained. Tho only satisfactory solution of the problem lies in tho re? covery of all of the ore proper, entirely free from foreign material. Some experience a few years ago with a method of water-separation ac? quainted me with the futility of at? tempting this result by that means or any other at that time known. With the modern demand for the rich material, it is easy to anticipate that the blast? furnace cannot exist among abandoned ore-beds. And the fact must not bo overlooked that in this country nearly all of, the older blast-furnace plants were located within or adjacent to the brown-hematite regions. A perfect method of concentrating would mean a survival of the brown-hematite oro as a source of supply. On rapidly drying a small sample of liiuonite over a powerful Dunsen flamo on one occasion, I observed that the smaller particles were magnetized. Could the ore lie magnetized? A trial on a more practical scale convinced me that such was the case. I then experi? mented with several different ores, and found that all the ore particles were so strongly affected as to ; permit their complete separation by means of a magnet. Naturally, a series of experiments fol- i lowed, in every instance giving the same | results. My attention was then directed toward finding out the conditions as well as the cause of the phenomenon. This led me to the conclusion that tin- agency of heat in the presence of carbon or carbon dioxide magnetizes the hydrous oxides of iron. Further tm I will endeavor to qualify this statement; but before beginning its discussion it may be interesting to allude to the practical method and the results, from a commercial standpoint, of some of the experiments. The ore is placed in a convenient re? ceptacle and merely roasted by the usual process, using eithor solid or gas fuel. It is undesirable to use much heat, since at a temperature of cherry red magnetization is fully imparted. Tho on' is drawn as fast as it reaches this temperature, and is at once ready for magnetic separation. In the following list, for obvious rea? sons, the ores are designated alphabet? ically: Of Ore ttc 1 run in covered its Iron in Cone en- Iron iu Concon CrudoOru tr?te. Tailings, irate. Percent. Percent. Percent. Percent. A, 40.08 55.SS . _ It, 34.32 51.73 . _ C, 38.0? 45.24 . 08 I), 40.03 50.04 _ Ho E, 20.30 40.32 5.21 55 F, 40.00 53.71 _ C> G, 4!) 00 _ HO II, 37.00 50 _ 05 I, 41.31 52.50 _ 85 .1, 35.35 55.04 _ 00 K, 33.55 48.03 2.40 70 L, 31.31 48.78 5.20 70 M, 30.84 51.20 5.00 78 N, 42.55 55.30 5,70 80 O, 43.84 55.01 - 70 P, 42.110 54.43 _ 85 A, 1?, C, I) and E aro from Pennsyl? vania, A and D being wash-ore: C, washed and jigged ore; 1), a line refuse sand; and E, a similar material: b\ an ore separated by a Bradford jig; 0, oro from a Northamton County, Pa., mine; II, the tailings rejected by a new jig: L a Pennsylvania ore; .1, a lot of six cars of ore "condemned" at the works; K and L are from tho same mine iu Pennsylvania and impossible tosoparate by water-jigging: M is a mixture of tine ore from Pennsylvania mines; O, an ore from Connecticut, and P, the tine ore from a large mine in Now York. The commercial success of treating ores in this way depends on the three items: cost of wash-ore; cost of roasting; cost of concentration. The first may be considered to range from 75 cents to SI.50 per ton, according to locality. The second item will bo fully covered by the following .statement, taken from the books of a large company exclusively engaged in roasting carbonate ores, and THE TIMES la tho lending paper of tho mineral bolt of tho two Virginias. If you want to koop posted on tho development of this section you cunnot allord to be without it. ut that time under tho most capable management. Actual cost of roasting and handling per ton ot ore: itoABTnra ORB. 1880. 1887. 1SS8. Labor, including car and topman.SO. 0083 80.0073 80.0811 Supplies. 0.0024 0.0033 0.0001 Coal. 0.0725 0.0750 0.0748 SO. 1033 80,1455 80.1050 Clum, per ton- 2.00 2.10 2.25 Average cost, SO. 1000. About one ton of culm used to 30 tons of ore. HANDLING AND WHARF KXI'KXSKS. 1880. 1S87. 1888. Labor, including engineer a n d teamster.80.0514 80.0439 80.0720 Supplies and coal 0.0177 0.0133 0.010'.? Team. o.ooio 0.0002 Repairs, etc. o.ooto 0.0025 0.0020 80.0731 80.0030 80.0980 Average.SO. 0700 Average total cost. 0.2300 I'er ton of ore treated. Tho third item remains to be deter? mined, namely, the cost of concentra? tion. Including royalty on the process. This would bo 2 cents per ton for con? centrating and 25 cents royalty: Taking as an example ore "K" in the foregoing list, the cost of the concentrated ore would be as follows: Cost of ljj' ton ore. 82.25 14 roasting. 30: " concentration and royalty. 27 82. 88 At a yield of 48 per cent, iron, this is 0 cents a unit, or, in sound numbers, 0.00 to tho ton. To determine tho extent to which the other constituents of the ore were affected, I tested several of the ores, of which two examples will sutlico. They gave tho following results: Ore E. Raw. Concen. Tailings. Iron, 20.30 40.32 5.21 Phosphorus, 0.12 0.30 0.09 Ore M. Iron, 31.31 48.87 5.20 Silica, - 20.25 83.20 Manganeso, - 2.20 1.18 Tho surprisingly small amount of fer? rous oxide in tho magnetized ore leaves the question, whether magnetization is wholly duo to its presence, very uncer? tain. In tho list of ores given, G, carry? ing 00 per cent, of iron, which would be. presumably high in ferrous oxide, con? tains but 3.07 per cent, ot ferrous oxide. In some cases the raw ore contains near? ly this amount. If the reduction caused by roasting were tho sole cause, it would be reasonable to expect the exterior of the particle to be the magnitizod portion. Rut lumps of the roasted ore having been broken, small pieces, carefully selected from tho inside of the lumps, showed in some cases even more strongly marked magnetic properties. A number of trials with the anhydrous oxide, both red and specular hematites, conducted in pr< cisely the same manner, gave no evidence whatever of result? ing magnetization. Crystallized speci? mens remained likewise unaffected. While the porous character of the brown hematite would permit permeation by reducing the gases, it is difficult to un? derstand how such minute deoxidization could magnetize it so strongly. More? over, the magnetization appears to be permanent. Samples which I have kept for over a year in contact with air have preserved the quality unimpaired. Cooling the red-hot oxide in water af? fects it somewhat, but it is still capable of responding through that medium to the attraction of a magnetic field. The phenomenon seems to he connect? ed with the expulsion of the combined water, and I think is largely depend? ent on its physical separation from the ore. During tho processs some of tho oxides glow quite strongly. The raw oxide, when heated to redness in a | closed glass tube, gives off a small amount of carbonic acid with its water, but is only feebly magnetic. There is no apparent evidence that ferrous oxide is produced by decomposition of the water. Tho ohly statement now possi ble is that the bydrated oxides of iron become magnetized at a red heat in con tact with carbon or carbon dioxide. It may be worth noting that the idea of employing a magnetic separator in a process for ??manu" facturing cast steel and malleable iron of a superior and uniform quality directly from ores" was announced some years ago. The curious supposition on which it was based was, that when "im? pure ores" are brought to a white beat ill a furnace (thereby producing metallic sponge), they can be separated from '?pure ores'* by the "simple mechanism of revolving magnets." Some of the "noxious elements" thus to be eliminat? ed1 were "titanic acid, vanadic acid, chromic acid, sulphuric acid, sulphur phosphorus, phosphoric acid, silicic acid, silicates." The resulting product was to bo simply melted. It is ol course a logical deduction, that all hydrous ores of iron become magnetic in the blast-furnace, aud that at the proper zone even anhydrous hematite does so. Ore concentrated as above de? scribed is peculiarly adapted to use in the blast-furnace. Before the ore-parti? cles reach a red heat in the process of roasting, violent decrepitation takes place, thus breaking or splitting up into small fragments all lumps of ore. This stale is most desirable for rapid reduction in the blast-furnace, and, aided by the easy fusability of the ore, offers the most favorable conditions for "driving" and regularity of work. The subject-matter outlined in this paper is embraced in a process on which application for letters-patent has been made. ADItlNti HEAVY MACH1NKRY. The American Bridge Works Materially Improving Their riant. Several heavy pieces of machinery were placed in position at tho newly erected blacksmith department of the American Bridge Works yesterday and more is on the road. It is expected that this department will go into operation within two weeks. Work has been greatly thrown back at the works by a scarcity of iron, which has to ho ordered from the North. It seems that the iron is delayed along tho road from some unaccountable cause, and the works are seriously inconven? ienced on this account. Tho manage? ment realize the importance of more Iron-working mills in this vicinity, and are looking forward with great anxiety to their establishment. WYTHE COUNTY, VA. Distinctly tie Richest Mining Town in Southwest Virginia. Tho largest mines, the richest lands, the finest timber surrounds Ivanhoo. The No. 1 furnace of the New RivA.J Mineral Company now in successful operation. Large Foundry, Machine Shops and Stove Works Under construction. Free s>'..? and liberal inducements to manufacturers. Immense limestone and iron and zinc mines are being worked or developed within the town. Important industries secured, and negotiations pending for others. A railroad junction in the heart of the greatest iron region in the United States. The only town on this great Southern connec? tion of the Norfolk and Western system. The world famous limonite and mountain ores of tho Cripple Creek Val? ley and tho celebrated Gossan and magnetic ores of Carroll county are within minimum haul of Ivanhoe. In direct communication with tho Pooahontas coal and coke fields. Reing 2,000 feet above the sea the climate is unsur? passed by the celebrated mountain resorts of the world. Vast tracts of Virgin forests close to band that can be floated down to Ivanhoe. Magnificent hotel, stores and dwellings under contract. The cheapest and best lots in the South. The Ivanhoe Land and Improvement Company are now receiving applica? tions for lots. Only those lots that have two or more applicants will bo oilered at auction. GREAT SALE OCTOBER 15, 1890. A grand chance for investment. Maps, price lists, plans, plats, etc., sent on application. Railroad fares from points within the State to Ivanhoe will be refunded to those buying lots. Ivanhoe Land and Improvement Co. Geyer's Tailoring Parlors. Our stock having been destroyed by fire, we have just received an entire new line of goods which we should be glad to have our patrons and the ? people of Roanoke, generally, call and examine. No trouble to show goods. Summer Clothing .ajt cost In order to get ready for ^^ZLZL STOCK. FRANK BROS., Tef^erson. Street- tf J. R. GREENE & CO., SUCCESSORS TO Duffey & Greene, Are now selling out their immense stock of Spring and Summer Clothing _A- T COST, Preparatory to removing in their new and elegant storo rooms on Jcfforsoa street next to the Times building. Go and sec them; they will treat you right. LROADS. ^HBNANDOAllN VALLMY RA J ROAD. S. P. Tvr-Kit, Receiver. . Schedule in effect Juno 2. 1800. ARRIVE AT ROANOKE. -.00 p. m. Daily?"Memphis Expreiss,' from Ilugcrstown and the North. Through Pullman sleeping cars from Now York and Philadelphia to Chattanooga and Memphis via Uarrisburg, Uagcrsj town and Roanoke. 11 .40 a. m. Daily?Now Orloans Exf , press from Now York, Philk adulphia and Baltimore/] making connection througll to tho South. Carries] tli rough Pullman palace ? buffet sleeping car from1 Philadelphia to New Or-1, leans, without change, via ! Harrisburg, Hagcrstownj Roanoke. Cleveland, Cajor'a and L. & N. R. R. LEAVE ROANOKE. 5:45 u. m. Daily?Baltimore Express from all points south for.'] Washington, - Baltimore, llarrisburg, Philadelphia and New York. parries Pullman palace buffet sleeping car from Roanoke to Philadelphia without change, via llagerstown and llarrisburg. 7:20 p. m. Daily?New York and Phil? adelphia Express, from Memphis, Chattanooga and all points south. For Phil? adelphia and New York. Carries Pullman palace buffet sleeping oars through to Philadelphia and New York via Roanoke, H?gers town and llarrisburg. , Ticket agents will furuish all infori mation and through schedules upon an plication to O. HOWARD ROYER tf 0. P. & T. Agent, Roanoke, Val NORFOLK & WESTERN RAIL1 ROAD. Schedule in effect Sept. 3rd, 1800. ! WEST BOUND. LEAVE ROANOKE. 10:0.""> a.m. Daily; arrivo Bristol 4:0V p. m. Stops at all stations connecting at Radford witlji ? trains on Now Rlvor Branch arriving at Pocahontas a 3:35 p. m. 5:45 p. m. Daily, arrives Radford 7:2<j,'1 p. m., connecting with New River Branch at 7:35 p. m for Bluofield and Pocahor 1 tas: arrives Pocahontas 10:5!! p. in. Arrives Bristol ll:2li p. m., connecting with El! T. V. & G. R. R. for all] points south and west. Ha1 Pullman Palace Sleeper Roanoke to Memphis, with out change. 7:55 a. m. Daily, arrivo Radford 0:1 a. in., connecting with Nevj River Branch, leaving Rad, ford 12:10 p. m. Arrive Bristol 12:40 p. in.,conneeh with E. T. V. & O. R. RJ for all points south an west; has Pullman Palac Sleeper from Roanoke tj N ow Orleans wiihou change. EAST BOUND. LEAVE ROANOKE. 5:25 a. m. Daily; for Lynchburg, Pi torsburg, Richmond, (vi I Petersburg and R. & P. I; R.,) Norfolk and intermit diate points; Connects ' iL' Lynchburg with V. M. If R. for Washington and th East, leaving Lynchbuil 7:40 a. m. daily. Arrive Norfolk 2.oo p. m., cennecj ing with steamer lines \ Baltimore and New York. 10:10 a. m. Daily; arrives Lynohbui 11:50 a. m., connecting win V. M. R. R. for all polnf north, arriving WashinJ ton 7:05 p. m.; arrives Pj torsburg 4:20 p. in.; arrivj Richmond, via R. & P. 1 > R., 5:05 p. m.; arrives No ' folk 7.00 p. m. \ , 3:45 p. m. Daily: for Lynchburg a* intermediate stations; ;0 rives Lynehburg 5:40 p. nj 7:20 p. in. Daily: for Lynehburg al intermediate! stations; : fr rives Lynehburg 0:20 p. 1 Cripple Creek Extension?Loav] Pulaski 8:15 a. m. Daily, except. f-Ju, day, and 3:00 p. m. Daily, arrive Iva hoe 0:45 a. m., and 4:30 p. in. Clinch Valley Extension (in operatij Aug. 3, to St. Paul, 81 miles)?Lea! Bluofield 8:10 a. m., daily; arrivo t. Paul 12:55 p. m. {> All inquiries as to rates, routes, eh promptly answered. ) / W. B. BEVTLL, !' Gen'l Pass, and Ticket Agentf CHAS. G. EDDY, vice-president. |l janl General Ottices. Roanoke* The East Tennessc Viryinia & Georgia RAILWAY SYSTEM IS THE ONLY SHORT AND DIRE( LINE TO THE South. Southwest k We' The finest Pullman Vestibule sh< ing car service in the South?Pullrf Sleepers without change, Roanoke Knox villi-, Chattanooga, Rome, An ton, Selina, Montgomery, Mobile New Orleans. Direct connection made at RomVi? Chattanooga with through sleepers f ATLANTA, MACON & JACKSOHYI For any further information, ad E. A. WARREN,jj. Trav. Pass. Agt., Bristol, Tg' C. A. BEN SCOT ER, Ass. Gen'l Pass. | B. W. WRENN, jy25tf Gen. Pass. Agt. Knoxvllle.Tj Jno. D. Stuart, IL M. Hec] Formerly of Danville. Notary I'uhlls Attorncy-atv STUART & HEUSE Real estate agents, Ivanhoe, W county, Va., buy and sell, on com sion, town lots. Mineral and far* land a specialty. All business entrxi to us will bo promptly attendee] Correspondence solicited.