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By T. Sterry Hunt

THE Jones Mine (or Johannes Mine, as it was originally called, from a former proprietor), situated near Springfield, in the township of Caernarvon, Berks County, Pennsylvania, has long been known as a large deposit of magnetic iron ore, associated with more or less copper pyrites, and with malachite and chrysocolla. It occurs in a belt of soft schistose rocks which rest upon the Laurentian gneiss of the Welsh Mountain, and to the northward are soon concealed by the unconformably overlying Mesozoic sandstone of the region. These metalliferous strata belong to the Primal slates of Rodgers, which, in many other localities in this region, include similar deposits of iron ores associated with more or less copper, and often accompanied by chloritic and argillaceous schists, and, more rarely, by serpentine and small lenticular masses of crystalline limestone. To this same horizon belong the iron ores of Boyertown, Fritz's Island, and Roudenbusch, near Reading, Wheatfield, Cornwall, and Dillsburg (all of which are found along the northern border of the Mesozoic belt of * By the kind permission of Dr. F. A. Genth, of the University of Pennsylvania, I am now enabled to append to this paper the following hitherto unpublished analyses of the Cornwall ores.

Jan 1, 1876

CHARLES P. BROOKS Charles P. Brooks, who had been identified with the mining industry in the West since 1874, having served at various times as mining and consulting engineer for most of the largest mining properties in Utah, died Dec. 11, at his home in Salt Lake City, of heart failure, after an illness of about one month. He was a very close business friend of the late Thomas Kearns and David Keith. In recent years he had been closely identified with the Silver King Coalition Mining Co., the Chief Consolidated Mining Co., the Grand Central Mining Co., the Prince Consolidated Mining & Smelting Co., and many other large properties. Mr. Brooks was born in Washingtonville, Orange County, New York, Aug. .21, 1851; he was the son of Charles Edward Brooks and Adeline Cannon Brooks. When 14 years of age he attended school at Chester, N. J., for one term, and accompanied the assistant principal of Chester Academy to New Paltz, N. Y., and finished the school year there. In 1866 he entered Dr. Stiles's school at Deckertown, N. J., and later the Sheffield School at Yale in 1867, where he received the degree of civil engineer with the class of 1870.

Jan 2, 1919

By F. W. Bowdish

Analysis of data on the equilibrium exchange of sodium ions from salt solutions for calcium ions, from various fractions of an oxidized calcareous iron ore from Lorraine, France, strongly suggests that the calcium may be attached to the solid by only one of its bonds. Nearly equal values were found for the equilibrium expression from data covering concentration ranges of 1000 fold for the salt and 235 fold for the ion-exchangeable calcium. Differences indicated between the exchangeable calcium contents of the slime and the sandy portions of the ore, as well as the equilibrium relationship itself, are of importance in the flotation of the ore. During an experimental program on the flotation of oxidized calcareous iron ores from Lorraine, France, ion-exchangeable calcium was found in the ore. Because this source of calcium ions, if not controlled, could thwart all efforts at flotation, an extensive study was made of the phenomenon. The part of that study reported here was to obtain data on the equilibrium established between ore solids and solutions of sodium chloride, and to analyze the data to try to understand better the physical chemistry of the exchange. The ore contains oolites of goethite and quartz grains embedded in a matrix consisting of calcite and a brown cement believed to be the residue from oxidation of the silicate minerals found in fresh unoxidized ore. When ground, a substantial fraction of the ore becomes a fine slime in which is concentrated more than half of the alumina content of the ore. It is believed that the alumina occurs as unidentified clay minerals with which most of the ion-exchange capacity of the ore is associated. A preliminary experiment on the exchange of ions from the ore for sodium ions from solutions of NaCl showed that calcium was about ten times as abundant as magnesium in the exchange solutions. Thus calcium was the predominant ion in causing difficulties with flotation, and it was the only one for which data was obtained in this study. It is believed that the omission of magnesium ion exchange from consideration does not invalidate the results. It is possible, however, that inclusion of magnesium in the analyses and calculations or its prior elimination from the samples would have improved the consistency of the results. EXPERIMENTAL Data about the equilibrium exchange of sodium from solutions for calcium from the solids were obtained using two different samples of material. The solids

Jan 1, 1963

By R. W. Raymond

I DESIRE to call the attention of the Institute briefly, and by no means in the way of an exhaustive description, to the interesting developments recently made on the east bank of the Hudson River, in the mining of spathic iron ores. The mines to which I refer are those of the Hudson River Spathic Iron Ore Company, situated at Oakhill on Hudson, Columbia County, N. Y., five or six miles from the city of Hudson, and opposite the town of Catskill. The ore occurs in beds, constituting apparently members of the stratified series of rocks on that side of the river, coursing nearly north and south, parallel with the river, and dipping east. The principal outcrops are presented in a range of low hills, about one mile from the river, along the crest, on the western face of which the stratum of spathic ore is more or less exposed. The length of the line in this range, along which, at various openings the ore has been discovered in profitable quantity, is about two miles. To the northward, the hills are somewhat higher, and the stratification may possibly be disturbed, though the rapid examination of the locality which I made in November last did not, include any determination of this

By R. W. Raymond

I DESIRE to call the attention of the Institute briefly, and by no means in the way of an exhaustive description, to the interesting developments recently made on the east bank of the Hudson River, in the mining of spathic iron ores. The mines to which I refer are those of the Hudson River Spathic Iron Ore Company, situated at Oakhill on Hudson, Columbia County, N. Y., five or six miles from the city of Hudson, and opposite the town of Catskill. The ore occurs in beds, constituting apparently members of the stratified series of rocks on that side of the river, coursing nearly north and south, parallel with the river, and dipping east. The principal out- crops are presented in a range of low hills, about one mile from the river, along the crest, on the western face of which the stratum of spathic ore is more or less exposed. The length of the line in this range, along which, at various openings the ore has been discovered in profitable quantity, is about two miles. To the northward, the hills are somewhat higher, and the stratification may possibly be disturbed, though the rapid examination of the locality which I made in November last did not, include any determination of this

Jan 1, 1876

By E. T. Dumble

THE development in the Gulf Coastal Plain for the year 1923 was entirely devoid of any spectacular feature and was considerably less than that of 1922. No large fields were discovered and the principal advances lay in the extension of the old fields and the finding of a new dome and other possible producing structures, which, however, so far, have given only small wells. While the production of some fields, such as those at Hull and Orange, was materially increased at times by comparatively large wells, the output as a whole shows a marked decrease over that of the preceding year. TABLE 1.-Production by Fields in Gulf Coastal Plain in 1923 FIELD BARRELS FIELD BARRELS Anse La Butte 16,942 Jennings 212,376 Barber's Hill 172,660 Markham 39,290 Batson 391,857 North D ayton 74,983 Big Hill (Jefferson County) 13,853 Orange 5,311,995 Blue Ridge 332,445 Pierce Junction 332,565 Damon Mound 822,355 Richmond (Big Creek) 17,545 Edgerley 176,964 Saratoga 700,661 Goose Creek 6,251,761 Sour Lake 2,091,961 High Island 19,018 Spindletop 309,315 Hull... 7,732,139 Vinton 2,134,430 Humble 2,449,744 West Columbia 6,598,589 36,203,448

Jan 3, 1924

By Henry S. Brown, Jean E. Tilden

Pyrite, pyrrhotite, chalcopyrite, and sphalerite from deposits distributed within the Piedmont and Blue Ridge provinces of North Carolina and adjacent areas were examined by atomic absorption spectrophotometry for cobalt, nickel, manganese, lead, tin, chromium, molybdenum, and gold. The ore samples were also examined petrographically. Cobalt and nickel, in general, enter pyrite and pyrrhotite rather than chalcopyrite and sphalerite. Manganese generally enters sphalerite rather than the other phases where an alternative is possible. The presence of tin in sulfide minerals was noted in a group of deposits east of the known occurrences of tin oxide (cassiterite) in the Kings Mountain belt, which may indicate the presence of a more extensive tin belt in the southeastern Piedmont than was previously recognized. Pyrrhotite from a group of four deposits in Jackson and Clay Counties, North Carolina, differs from pyrrhotite from other Ducktown-type deposits in having cobalt/ nickel ratios less than one, finer grain sizes, and colloform texture. These differences suggest that that this group of deposits has had a history different from that of the other Ducktown-type deposits studied. No significant conclusions could be made based on the distribution of lead, chromium, molybdenum, or gold.

Jan 1, 1975

By M. B. Holt

At this time, when electricity in its various applications is attract- ing so much interest, and with such good reason, it has been suggested to me that, as the Aspen Mining and Smelting Company, of Aspen, Pitkin county, Colorado, was the first mining company in America to employ electrical power for hoisting, a record of what has been accomplished by this company would be of interest. Early in the year 1888 the question of power for the development of the ore-horizon lying below the level of the tunnel through which the property is worked, became one of importance. The conditions under which it was proposed to use power were as follows (See Fig. 1): The company's mines lie upon the northwestern slope of a mountain, the ascent of which is at an angle of 28' from the horizon. The ore, consisting of argentiferous galena and other silver-bearing mineral, is found at or near the plane of contact of a superincumbent mass of blue limestone, with an underlying bed of dolomite. This contact plane dips north 30° west, at an angle of 60' with the horizon. A tunnel 1000 feet in length, driven south into the mountain near

Jan 1, 1892

By Rip Thompson

ALTHOUGH the metallurgical treatment for the Ophir Hill tailings was developed more than 20 years ago and in the interim a vast amount of experimental work was done with later-developed flotation rea-gents, it was found necessary to revert to the original oil reagents and their combina-tions with specific chemical reagents in order to obtain results of economic value. This is of especial interest because in present ore-treatment investigations later-developed flotation reagents are used almost exclusively and the coal-tar deriva-tives, except in certain patented reagents, are virtually neglected. These coal-tar oils and derivatives still have a definite field of application, especially in the treatment of some oxidized ores when modified sulphidi-zation is desirable. The Ophir Hill tailings deposit is in Ophir Canyon, Tooele County, Utah, about 55 miles southwest of Salt Lake City and 25 miles south of the Tooele smelter of the International Smelting and Refining Co. A road good for trucks leads directly from the Ophir mill to the smelter.

Jan 1, 1940

By Kenneth Cottingham

THE area described herein is situated on what is known as the Arches Fork anticline in Roane and Calhoun Counties, W. Va. When the area was first mapped, it was felt that well records would give a more intimate idea of conditions, both structural and lithologic, than could be expected from surface horizons. The surface formations are chiefly members of the Monongahela series, though northward the hilltop outcrops are those of the Dunkard. Neither series offers a key horizon sufficiently definite to be satisfactory, although the structure as determined from well records was later checked against two of the more persistent surface sandstones. In mapping the subsurface structure, the top of the Big Lime (Greenbrier) was employed as the key horizon. The average depth to the top of the Big Lime varies from 1600 to 2000 ft. (487 to 609 m.), while the average thickness as indicated by well records is 113 ft. (34 m.). The oil-producing formation is the Big Injun, lying just below the Big Lime. In two instances, well records show the Lime and Injun separated by a few feet of "break." The Big Injun is recorded as having a variable thickness. Seven logs report it as missing and one gives it the maximum thickness of 105 ft. (32 m.), while the entire average for thickness is 19 ft. (6 m.).

Jan 1, 1922

By J. B. Mackintosh

Some months ago I received a sample of a highly crystalline product occurring in the hearth of the shaft-furnace used in smelting the roasted niccoliferous pyrrhotite at Mr. Joseph Wharton's works near the Gap Mine, Lancaster County, Pa. Mr. Wharton first observed this product in cavities in the concretions in these furnaces about the year 1870, and published a description of it in that year.* Thinking that it might show some analogy to meteoric iron, he sent the present sample to Mr. George a F. Kunz, who turned it over to me, with the request that I should analyze it at my convenience. The results do not show the expected analogy, because the sulphur in meteoric iron is combined as FeS., while in this product there is only one-sixth the necessary amount of sulphur, which, however, seems to be combined with all the metallic elements present, forming a sub-sulphide of definite composition. I am informed by Mr. Wharton that he has had for a long time the sample which I have analyzed, and that it probably is about the same age as that which he first described. It is worthy of note that the material does not show any signs of oxidation, but that the crystals preserve a brilliant metallic lustre. The first two analyses, made by Mr. J. Voigt, are those given by

Jan 1, 1888

J. J. RUTLEDGE,* McAlester, Okla. (written discussiont).-Research work has often a more immediate and practical application to the in-dustries than even the investigators themselves realize, but coal mining has not attracted the investigator, except in so far as the mine-accident prevention work and fuel investigations are concerned. In future, the coal geologist will study the subsurface geology of the various coal seams as the petroleum geologist now studies the oil sands, and from the results of these studies the coal operator will be able to locate his shafts to the best possible advantage and to avoid faults that would interfere with underground work. There would have been many thousands of dollars saved, and perhaps some reputations, if a good stratigrapher. had been called into consultation in the southern part of Somerset County, Pa., where a local seam of coal, quite thick, was mistaken for the Pittsburgh seam, which, if ever present at that point, had long since been eroded. Why will the Quemanhoming coal carry more sulfur without injuring the grate bars than George's Creek Big Vein? Only the investigator can answer and yet the fact that the above is true means a greater price for the thinner coal. The owner of the land in Oklahoma receives one-fourth of the cotton crop produced by the tenant who farms his land and one-third of the

Jan 11, 1919

Geological and Natural History Survey of Minnesota, Minneapolis, Minn W. H Emmons, Director A list of publications will be sent upon application Orders for publications should be addressed to The University of Minnesota Press, Minneapolis, Minnesota The Geological Survey of Minnesota has a record of long and useful service Some of the papers published have been outstanding in their field A series of 24 Annual Reports, covering the years 1872 to 1895-98, inclusive, was issued, of which 16 are still available at a price. More important however, are the six volumes of Final Reports, in which is collected the material presented in the earlier Annual Reports. All the strictly geological papers are found in four of the volumes of the Final Reports. vol 1 (1872-1882), principally geology by counties, 2 (1882-1885), same as 1, 4 (1896-1898), same as 1, 5 (1898-1900), Structural and petrographic geology Prices for each volume, leather $3, cloth $2 50, excluding postage, unless other directions accompany the order, volumes of the Final Reports will be sent express collect. A series of Bulletins has been issued, of which a few are out of print. Considering only those available, and of greatest interest, they are: Bulletin 5, Natural gas in Minnesota, by N H Winchell (1889), 50 cents, 6, Iron ores in Minnesota, their geology, discovery, development, qualities and origin, by N H Winchell and H V.

Jan 1, 1933

By John Gjers

Being on a visit to your great and prosperous country, and having been favored with an invitation to attend this meeting of your Institute, the author has been requested by your Secretary to give a short account of his invention of the " soaking-pit," which he has great pleasure in doing. The object of the soaking-pit is the rolling of steel ingots with their own initial heat, that is, to supply the missing link in that chain of metallurgical operations which Sir Henry Bessemer began in 1857, when he proved how it was possible to produce malleable iron or steel direct from the fluid cast-iron out of the blast-furnace, without any further direct use of fuel. The great Bessemer invention has revolutionized iron and steelmaking throughout the world; but it stopped short at producing the ingot, which, it was found, had afterwards to be heated in a furnace to enable it to be rolled or hammered; and it is only lately, twenty-five years after Mr. Bessemer's announcement, that the author of this paper has been able to show that furnacing can be dispensed with, and that it is practicable to roll a steel ingot into say a bloom, a rail, or a billet, with its own initial heat. It has no doubt suggested itself to many that there ought to be heat enough in the ingot just cast, for the purpose of rolling; and from time to time attempts have been made to utilize this heat; but such attempts always ending in failure, it became a settled opinion in the trade that it could not be done—an opinion which the author is aware that your late lamented countryman, Mr. Holley, than whom there was none more conversant with Bessemer steel-making, also entertained. But settled opinions sometimes prove to be great fallacies. As an instance, it is not many years since the opinion prevailed in the trade that steel ingots could not be rolled successfully, that is, so as to make good rails, unless they were first allowed to get quite cold, and afterwards heated. No greater boon was ever conferred on the

Jan 1, 1885

By Walter Mathesius

The use of high blast heats on furnaces melting Mesaba ores is still the exception, the average blast temperatures carried on Mesaba stacks seldom reaching 1,100" F. Some 15 years ago, when the use of fine Mesaba ores in larger proportions to the total burden first came into practice, it was found difficult to employ even those blast heats which it had been possible ' to carry with the Old Range ores. The furnaces refused to "take" high heats, and would persistently labor with irregular stock movement, which impaired the practice and increased the coke consumption. By lowering the blast temperature, the working of the furnace became smoother, and experience taught that with the softer and more easily reduced Mesaba ores, satisfactory practice could be obtained with comparatively low blast heats. Therefore a large number of Mesaba furnaces have ever since been operated on very low blast temperatures, ranging between 800" and 1,000" F. In the face of these difficulties, furnace men were slow to recognize that furnaces could be so designed as to permit a free movement of the charges in combination with the use of higher heats. Since higher blast temperatures did not seem to offer great advantages in the smelting of Mesaba ores, investments in hot-blast stoves were not as attractive to the furnace man as labor-saving devices and means of obtaining greater tonnages. The effect of this preference is keenly felt at the present time. It has brought about the peculiar situation, that the majority of our furnace plants (among them some of the most progressive) lack modern and efficient stove equipment. The result is that, even where the proper furnace lines have been adopted and conditions are now favorable to the successful employment of higher blast temperatures, the heats required for the greatest fuel economy are not available. In an endeavor to obtain results, even with inadequate equipment, we find that, at many plants, the stoves are worked far beyond their capacity. This leads, in many instances, to a situation in which the coke saving in the

Jan 1, 1915

By P. D. Frost, H. A. Robinson, J. R. Doig, M. W. Mote

The mechanism of hardening in heat-treatable zirconium alloys was foUNd to be analogous to that for titanium alloys. Zirconium containing a relatively large addition of a ß -stabilizing element such as molybdenum or columbium can be hardened by the following transformation: Lean alloys, having insufficient alloy content to retain ß at room temperature are hardened by the following transformation: Application of these findings in Zr-Mo-Sn and Zr-Nb-Sn alloys produced strengths as high as 190,000 psi with reasonable ductility. PRIOR research on zirconium alloys has been concerned with development of greater strengths and creep resistance by solid-solution hardening or by dispersion hardening. Although solution and aging heat treatments had been applied earlier to zirconium alloys, quenching frequently produced low ductility. The possibility that the ß-to-w transformation, discovered earlier in titanium alloys,' might also occur in zirconium alloys and cause low ductility was considered, and, indeed, was found as predicted2 to be the case. In the earliest experiments, the heat-treatment response of titanium, too, was disappointing. However, by avoiding the formation of the embrittling w phase, it became practical to obtain room-temperature strengths higher than 180,000 psi, with elongation values of 10 pct.3 Based on the present concept of titanium heat treatment, the principal requirement for a heat-treatable zirconium alloy is that it contains a certain minimum amount of one or more ß -stabilizing elements. Only molybdenum, columbium, and tantalum, when present in sufficient amounts, are known to stabilize ß zirconium to room temperature during rapid cooling from the ß field. Tantalum was undesirable because of its high thermal-neutron cross section. Aluminum and tin are effective a stabilizers, but aluminum has been shown to seriously decrease the corrosion resistance of simple zirconium alloys in hot water. Therefore, for the present study, tin was used as the stabilizer addition. The alloys selected for this evaluation are presented in Table 1 along with their analyses and ß-transus temperatures. The analyses indicated that intended compositions were usually realized. EXPERIMENTAL PROCEDURES All of the alloys were melted from sponge zirconium and fabricated to sheet for heat treatment

Jan 1, 1960

By H. C. Miller

THE gas-lift method of flowing oil from wells is the outstanding feature of petroleum technology today. Its forerunner, the air lift, was used successfully first, in the Baku fields of Russia, in 1899, and later in the Gulf Coast fields of Texas and Louisiana and the Kern River field of California. It is still used to a limited extent in certain oil fields. The use of compressed natural gas for lifting oil from wells has supplanted the air-lift method in a measure in those fields where a sufficient quantity of gas accompanies the oil to make the gas lift possible, or where natural gas is plentiful and inexpensive. We find therefore in California, that, natural gas is used at practically every well where a gaseous medium is employed to flow the oil. The use of natural gas has many advantages over that of air. It is possible to recover and save the gasoline from the gas that accompanied the oil to the surface. This gasoline would be wasted if air were used as the lifting medium. Also, certain proportions of air and gas form an explosive mixture that cannot be handled safely by compressors. Another advantage that gas has over air is that gas under pressure is more soluble in oil. Gas in solution in oil reduces the viscosity of the oil that is being produced and causes it to flow more readily through the. tubing and flow lines. The gas lift has made it possible to recover many thousands of barrels of oil from deep wells in California that could not have been produced otherwise. It would not have been economical, had it been mechanically possible to produce such wells as the world's deepest producing oil well (Miley Athen's No. 6, Rosecranz field, California) by any other method of pumping known today. At this well, production is obtained from between 7305 and 7591 ft. and 11 months after completion of the well, production was being maintained on the gas lift it approximately 2000 bbl. a month. The crookedness of the hole, or its diameter and depth will not prevent the successful application of gas-lift pumping when other conditions are favorable.

Jan 1, 1927

By A. L. Holley

The three principal mines from which the celebrated Salisbury iron ores are obtained are called respectively the "Old Hill," "Davis," and "Chatfield" ore beds, and are situated in the town of Salisbury, Litchfield County, Conn., on the eastern slope of the Tocconuc range of hills.* The Old Hill Ore Bed is a tract of land of 100 acres, originally granted by the General Court in October, 1731, to be laid out by Daniel Bissell of Windsor. It mas Boon after surveyed and located by Ezekiel Ashley and John Pell. The descendants of Ashley are still proprietors in the mine. The supply of ore has been very abundant, and for many years was easily obtained, but latterly the cost of raising has been greatly increased. Up to about 1840 the average yield was estimated to be about 4500 tons per annum. The production has gradually increased until the average yield at present is estimated at 15,000 tons annually. The largest production in any one ymr was about 20,000 tons. The proprietors of this mine were incorporated many years ago under the style of " The Salisbury Ore Bed Proprietors." The Davis Ore Bed, named after an early owner, was originally called Hendricks Ore Bed, and was owned before the organization of the town of Salisbury by Thomas Lamb, one of the first settlers

Jan 1, 1879

By W. T. Ober

the hammering effect acts only to a point 3 in. back from the cutting edge, and the hardening heat extends back only 1 in. from the cutting edge. Then, as a steel is taken from the fire, the grain condition is as shown in Fig. I. After the forging operation has been performed the condition shown by Fig. 2 exists. The heating operation to harden the cutting edge produces the effect shown in Fig. 3. The questions that naturally arise are: Will the cost of the extra heat treatment necessary to change this condition (annealing) be more than the saving that may be effected in the drill steel or will the extra heating be an economical as well as a wise thing to do? Is this condition necessarily detrimental to the maximum service of the drill steel? Can this annealing action be obtained in the hardening heat by heating more of the bit, say at least 5 in., to the hardening temperature but quenching only the end of the bit by a shallow immersion? Short Rock-drill Steels Reclaimed by Welding By W. T. Ober, Lynn, Mass. Experimental tests by the Thompson Company have shown that short lengths of rock-drill steels may be reclaimed by electric butt welding. The drills used in the experiments were hollow drills l1/4-in. in diametcr containing 0.95 per cent. to 1.05 per cent. carbon. The ends to be joined must first be ground off fairly square and the greater part of the rust, scale, etc. removed for 3 or 4 in. back in order to insure good electrical contact with the dies of the welder and countersunk, with an 80° countersink, approximately 1/4 in. The steels are then clamped in the copper dies of the welder, so that a length projects from the inside edge of each pair of dies equivalent to from one-half to three-quarters the diameter of the drill. The drills should also be brought into accurate alignment. The first step is to bring the ends into close proximity and then close the primary circuit of the transformer, slowly bringing the steels together until their ends lightly touch, when they will "flash," that is, minute

Jan 1, 1922

By W. T. Ober

the hammering effect acts only to a point 3 in. back from the cutting edge, and the hardening heat extends back only 1 in. from the cutting edge. Then, as a steel is taken from the fire, the grain condition is as shown in Fig. I. After the forging operation has been performed the condition shown by Fig. 2 exists. The heating operation to harden the cutting edge produces the effect shown in Fig. 3. The questions that naturally arise are: Will the cost of the extra heat treatment necessary to change this condition (annealing) be more than the saving that may be effected in the drill steel or will the extra heating be an economical as well as a wise thing to do? Is this condition necessarily detrimental to the maximum service of the drill steel? Can this annealing action be obtained in the hardening heat by heating more of the bit, say at least 5 in., to the hardening temperature but quenching only the end of the bit by a shallow immersion? Short Rock-drill Steels Reclaimed by Welding By W. T. Ober, Lynn, Mass. Experimental tests by the Thompson Company have shown that short lengths of rock-drill steels may be reclaimed by electric butt welding. The drills used in the experiments were hollow drills l1/4-in. in diametcr containing 0.95 per cent. to 1.05 per cent. carbon. The ends to be joined must first be ground off fairly square and the greater part of the rust, scale, etc. removed for 3 or 4 in. back in order to insure good electrical contact with the dies of the welder and countersunk, with an 80° countersink, approximately 1/4 in. The steels are then clamped in the copper dies of the welder, so that a length projects from the inside edge of each pair of dies equivalent to from one-half to three-quarters the diameter of the drill. The drills should also be brought into accurate alignment. The first step is to bring the ends into close proximity and then close the primary circuit of the transformer, slowly bringing the steels together until their ends lightly touch, when they will "flash," that is, minute

Jan 1, 1922