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By John A. Church

In the year 1874, when the price of pig-iron was still high, that staple product became the subject of discussion in the newspapers and among those philosophers who are determined to know the "reason why" for all things. The object of the inquiry was to find out Why iron did not fall in price as much as some other things had fallen. Indeed, there seemed to be an impression that iron and gold ought to move on nearly parallel lines, for the fact was constantly brought forward that iron then cost twice as much as it did before the war, though gold had returned to within twelve or fifteen per cent. of its former value. After some time the papers, by what seemed to be nearly unanimous consent, reached the conclusion that the maintenance of high prices was the work of the furnace proprietors, who, as the result of their shrewdness, were pocketing enormous profits. No proof was given to support this opinion, and the figures of cost and sale that were produced were of the most general kind, and used in the most vague manner. Visiting the president of the Thomas Iron Company, whose great works at Hokendaqua and Catasauqua, in Pennsylvania, are so well known as the largest and among the best conducted in America, I found him quite willing to meet the vague suspicions of the newspaper wiseacres, by a publication of the figures contained in the furnace-books of his company. These were accordingly given to the world through the Engineering and Mining Journal, and attracted the general attention they so well deserve. Though my own name became connected with these statistics, from the fact that I used them as the basis for the first attempt ever made to calcalate the furnace economy of an American works, I can, without the suspicion of egotism, say that the statistics referred to are the most valuable contribution the literature of American blast-furnace work has yet received, for their interest is independent of personal considerations, and due entirely to the fact that they represent faithfully the details of practice in one of the most prominent American works. They are an exact transcript of the furnace-books, and form a body of accurate information of the greatest value to the metullurgical student. Their importance is shown by the fact that though the theoretical conclusions which I based upon them have been several times attacked, not one of my critics has made the slightest contribution to

By John A. Church

IN the year 1874, when the price of pig-iron was still high, that staple product became the subject of discussion in the newspapers and among those philosophers who are determined to know the "reason why" for all things. The object of the inquiry was to find out why iron did not fall in price as much as some other things had fallen. Indeed, there seemed to be an impression that iron and gold ought to move on nearly parallel lines, for the fact was constantly brought forward that iron then cost twice as much as it did before the war, though gold had returned to within twelve or fifteen per cent. of its former value. After some time the papers, by what seemed to be nearly unanimous consent, reached the conclusion that the maintenance of high prices was the work of the furnace proprietors, who, as the result of their shrewdness, were pocketing enormous profits. No proof was given to support this opinion, and the figures of cost and sale that were produced were of the most general kind, and used in the most vague manner. Visiting the president of the Thomas Iron Company, whose great works at Hokendaqua and Catasauqua, in Pennsylvania, are so well known as the largest and among the best conducted in America, I found him quite willing to meet the vague suspicions of the newspaper wiseacres, by a publication of the figures contained in the furnace-books of his company. These were accordingly given to the world through the Engineering and Mining Journal, and attracted the general attention they so well deserve. Though my own name became connected with these statistics, from the fact that I used them as the basis for the first attempt ever made to calculate the furnace economy of an American works, I can, without the suspicion of egotism, say that the statistics referred to are the most valuable contribution the literature of American blast-furnace work has yet received, for their interest is independent of personal considerations, and due entirely to the fact that they represent faithfully the details of practice in one of the most prominent American works. They are an exact transcript of the furnace-books, and form a body of accurate information of the greatest value to the metallurgical student. Their importance is shown by the fact that though the theoretical conclusions which I based upon them have been several times attacked, not one of my critics has made the slightest contribution to

Jan 1, 1876

By Frank Haas

Many articles on the physical properties of fire damp have appeared in the Transactions and elsewhere but practically nothing has been written in regard to its occurrence or fluctuation in quantity in an ordinary mine. After the Monongah explosion in 1907, with the loss of 361 lives, the Consolidation Coal Co. sought a method by which such catastrophes could be prevented. While the cause of this particular explosion was attributed to coal dust, some of those acquainted with the mine thought that fire damp was involved, if it was not the initial cause. So the literature on the subject was studied and mines where similar conditions prevailed in this country and Europe, were visited, with the view of establishing some system by which gas could be more easily detected and controlled. The results of this study were disappointing for no method was found other than the time-honored fire boss with his safety lamp, with some variations in the rules and regulations governing his inspections and reports. Duties of the Fire Boss Pending the development of a better method, it was decided to standardize and perfect the duties of the fire boss and the reports based on his observations. Those who were then in service were closely examined, various lamps were experimented with and the lamps and individuals tested under known conditions. It was found that a fire boss could tell whether gas was present but his estimate of quantity was not even an approximation; therefore, while the services of fire bosses were indispen-sible there was need of additional information by which the quantity of gas could be estimated with some precision in order to determine its variation from time to time. Chemical Process for Determination of Methane After considering all methods known at that time a chemical process was adopted. The principles involved in the process are that in an enclosed receptacle, in the presence of excess air, methane will be completely burned by means of a hot platinum wire to carbon dioxide and

Jan 1, 1927

By Freeman Bishop

Mercury is the latest ecological disaster. It was believed to be no pollution problem because it is heavier than water and expected to fall to the bottom of streams. But the Food and Drug Administration (FDA) found that mercury in a dozen states and several Canadian provinces was being ingested by fish. A Deadly Dose First to sound the alarm was Canada when a graduate student's research revealed that mercury contamination in Lake St. Clair had reached 1.4 pmm. which is almost three times the 0.5 ppm the FDA's allowable maximum.

Jan 1, 1970

By W. H. Schacht

The operations of the Copper Range Co. are located in the Michigan copper district at the southern end of the Keweenaw Peninsula, 8 miles southwest of Hough ton (the center of the district). All the producing mines are situated in a long narrow zone paralleling the peninsula and occupying the central portion. This zone is about 25 miles long and 3 to 4 miles wide. The important mines, in their order from northeast to southwest, are, Mohawk, Ahmeek, Allouez, North Kearsarge, Wolverine, South Kearsarge, Centennial, Calumet & Hecla, Osceola, Franklin, Quincy, Isle Royale, Baltic, Trimountain, and Champion; the last three are operated by the Copper Range Co. The existence of copper deposits in this district became known soon after the discovery of America. Many references by early explorers show that copper was found in the possession of many of the American Indians that inhabited the Great Lakes region. There is abundant evidence that exploration of these copper deposits extended into prehistoric times; and some indication that the American Indians carried on operations shortly before the advent of white men. An account of the finding of primitive mining appears in the Government publications of 1850-51 by Foster and Whitney. Although earlier expeditions by white men had been made to the Keweenaw peninsula, an attempt to commercialize the district was not made until after 1765, when Alex. Henry, a British subject, searched the shores of Lake Superior for mineral treasure. His first expedition took him to the Ontonagon River, where he found the famous mass of copper now on exhibition at Washington. In 1771, he started operations along this river with a crew financed by English capital; but after much difficulty and only meager success he found only detached masses while in search for a major deposit. There is no record of any cxploration from 1774 to 1820. In 1838, Dr. Douglas Houghton was appointed state geologist. Prior to that time he had made several visits to this region; and was the first white man to find

Jan 1, 1925

By Harry E. Krumlauf

The year 1957 was one of declining metal price and production. Many lead-zinc-copper mines were forced to close, and the remaining mines limited production to stay more in line with demand. High cost of labor, supplies, and equipment and high taxes aggravated the situation. Some operators postponed or abandoned expansion programs because of uncertain economic conditions. Output was curtailed by elimination of over- time employment and reduction of the working force. The number of employes laid off was small- reduction in the labor force was accomplished by not replacing those who left a company's employ.

Jan 2, 1958

By George W. Maynard

For an account of the discovery and the determination of chromite on Port au Port Bay I am indebted to Mr. Obalski, Government mining engineer for the Province of Quebec. He writes: " In June, 1894, with the authorization of our Government, I went to Newfoundland to examine some asbestos property. Passing through Halifax, I had interviews with some gentlemen who told me that besides the asbestos there was in the same district a big deposit of iron-ore. They handed me some specimens, and, after ascertaining that they were not magnetic, and learning that they were found in serpentine, I said they were chromic iron. I visited the place on June 27, 1894, and confirmed my opinion, pointing out at the same time the importance of the deposit, as appears in my report of July 9, 1894. I do not claim any credit for the discovery of chrome-ore in Newfoundland; but, as a matter of fact. when I came in contact with the Halifax gentlemen they did not appear to know the nature or the value of the mineral until I mentioned to them that it was chromite. "' Mr. Obalski's report was mainly devoted to the asbestos-deposits. That portion relating to the chromite was as follows: " On the right side of the creek there is a show of chromic iron of good quality, which appears scattered through the serpentine in several places on the face of the cliff for 40 to 50 feet. A few boulders are found farther up at a distance of 100 feet, and also in the ckeek itself. From this point the deposit exists on a relatively large area, the widest exposures being from 6 to 7 feet. Chromic iron deposits in serpentine rock have no regularity, and are merely pockets. In the case of the property in question this rule is not changed, but the pockets look to be of large extent, and could be easily worked." My own preliminary investigation of the property was made

Jan 1, 1898

By Jeremias K. Chitunda

Significant cost savings and improved ground stability are two initial indications from the current wet process shotcrete ground support program at the Lakeshore mine. The area of shotcrete for ground stability is not strange to the Lakeshore operation. Since the beginning of the project, various shotcrete techniques have constantly been experimented with, incorporating all the latest technological developments. Over the years, the use of shotcrete has been employed as a primary, temporary, or permanent support, singly or in combination with rockbolts and steel sets. The extent of shotcrete usage compared with steel sets and rockbolts has varied from time to time as dictated by the overall state of the art. In 1972, for example, the ratio of the linear drift footage supported with shotcrete to that supported with steel sets averaged 1.0. In 1973, that ratio was about 3.0. Overall, for the Lakeshore mine, there are about 8000 drift ft of shotcrete, 8000 drift ft of steel sets and timber, 750 drift ft of formed concrete, 21,000 drift ft of rockbolts, and 3700 drift ft of combined type support.

Jan 12, 1974

By J. F. Haseman, J. E. Davenport

IN the brown rock phosphate fields of Tennessee there are large deposits of phosphate matrix in which quartz is a major constituent of the gangue, and which cannot be beneficiated by the conventional washing process to yield a concentrate of suitable grade for use in the electric furnace. A huge tonnage of high-grade phosphate concentrate is produced in the Florida pebble district from low-grade siliceous feed. However, the characteristics of the low-grade siliceous Tennessee ore are such that flotation under the conditions employed in treating the Florida ore1-2 results in inadequate beneficiation. INVESTIGATION OF FLOTATION METHODS Flotation has been used in Tennessee primarily to produce a concentrate of premium grade by moderate enrichment of a marketable grade of phosphate.3,4 A secondary use was to increase the recovery of phosphate from the fines (down to approximately 200 mesh) from medium-grade ores with a concomitant moderate increase in over-all grade.3,5 It was considered desirable to investigate methods of improving the grade of washed products from low-grade siliceous Tennessee ore when these products were substantially below the requirements for use in the electric furnace. The present paper describes the results of a laboratory-scale study of factors that affect the beneficiation of such siliceous phosphate ore by flotation. The primary objective of the investigation was to ascertain the conditions under which the ore could be made to yield a concentrate suitable for reduction in the electric furnace. It was assumed that a phosphate concentrate for electrothermal reduction should contain at least 26 pct P205 and should have a weight ratio of silica to lime of not more than 0.80. Since a concentrate of moderate grade can be used in the electric furnace, and since, as Grissom4 has shown in detail, the ore will not bear the cost of expensive treatment, the study of collectors was limited to the relatively inexpensive fatty acids. A secondary objective was to determine whether a portion of the phosphate could be recovered in a grade suitable for treatment with phosphoric acid to produce 45 pct superphosphate. The ore consisted of variably cemented sand interlayered with clay. The sand layers were composed of grains of quartz, phosphate, and clay embedded in a matrix of clay and phosphate. Some clay was finely disseminated in the phosphate grains. Little massive high-grade phosphate was present. The material used in the flotation tests was a washed sand that had been separated from the ore in a bowl classifier at the TVA phosphate-washing plant. The percentage composition of the sand was as follows: P205, 20; Si02, 40; CaO, 29; Fe203, 2; A1203, 3; F, 2.3. The particle-

Jan 1, 1947

By J. F Haseman, J. E. Davenport

In the brown rock phosphate fields of Tennessee there are large deposits of phosphate matrix in which quartz is a major constituent of the gangue, and which cannot be beneficiated by the conventional washing process to yield a concentrate of suitable grade for use in the electric furnace. A huge tonnage of high-grade phosphate concentrate is produced in the Florida pebble district from low-grade siliceous feed. However, the characteristics of the low-grade siliceous Tennessee ore are such that flotation under the conditions employed in treating the Florida ore1,2 results in inadequate beneficiation. Investigation of Flotation Methods Flotation has been used in 'Tennessee primarily to produce a concentrate of premium grade by moderate enrichment of a marketable grade of phosphate. 3,4 A secondary use was to increase the recovery of phosphate from the fines (down to approximately 200 mesh) from medium-grade ores with a concomitant moderate increase in over all grade.3,5 It was considered desirable to investigate methods of improving the grade of washed products from low-grade siliceous Tennessee ore when these products were substantially below the requirements for use in the electric furnace. The present paper describes the results of a laboratory-scale study of factors that affect the beneficiation of such siliceous phosphate ore by flotation. The primary objective of the investigation was to ascertain the conditions under which the ore could be made to yield a concentrate suitable for reduction in the electric furnace. It was assumed that a phosphate concentrate for electrothermal reduction should contain at least 26 pct P2O5 and should have a weight ratio of silica to lime of not more than 0.80. Since a concentrate of moderate grade can be used in the electric furnace, and since, as Grissom4 has shown in detail, the ore will not bear the cost of expensive treatment, the study of collectors was limited to the relatively inexpensive fatty acids. A secondary objective was to determine whether a portion of the phosphate could be recovered in a grade suitable for treatment with phosphoric acid to produce 45 pct superphosphate. The ore consisted of variably cemented sand interlayered with clay. The sand layers were composed of grains of quartz, phosphate, and clay embedded in a matrix of clay and phosphate. Some clay was finely disseminated in the phosphate grains. Little massive high-grade phosphate was present. The material used in the flotation tests was a washed sand that had been separated from the ore in a bowl classifier at the TVA phosphate-washing plant. The percentage composition of the sand was as follows: P2O5, 20; SiO2, 40; CaO, 29; Fe2O3, 2; Al2O3, 3; F, 2.3. The particle-

Jan 1, 1948

By J. F. Haseman, J. E. Davenport

In the brown rock phosphate fields of Tennessee there are large deposits of phosphate matrix in which quartz is a major constituent of the gangue, and which cannot be beneficiated by the conventional washing process to yield a concentrate of suitable grade for use in the electric furnace. A huge tonnage of high-grade phosphate concentrate is produced in the Florida pebble district from low-grade siliceous feed. However, the characteristics of the low-grade siliceous Tennessee ore are such that flotation under the conditions employed in treating the Florida ore1,2 results in inadequate beneficiation. Investigation of Flotation Methods Flotation has been used in 'Tennessee primarily to produce a concentrate of premium grade by moderate enrichment of a marketable grade of phosphate. 3,4 A secondary use was to increase the recovery of phosphate from the fines (down to approximately 200 mesh) from medium-grade ores with a concomitant moderate increase in over all grade.3,5 It was considered desirable to investigate methods of improving the grade of washed products from low-grade siliceous Tennessee ore when these products were substantially below the requirements for use in the electric furnace. The present paper describes the results of a laboratory-scale study of factors that affect the beneficiation of such siliceous phosphate ore by flotation. The primary objective of the investigation was to ascertain the conditions under which the ore could be made to yield a concentrate suitable for reduction in the electric furnace. It was assumed that a phosphate concentrate for electrothermal reduction should contain at least 26 pct P2O5 and should have a weight ratio of silica to lime of not more than 0.80. Since a concentrate of moderate grade can be used in the electric furnace, and since, as Grissom4 has shown in detail, the ore will not bear the cost of expensive treatment, the study of collectors was limited to the relatively inexpensive fatty acids. A secondary objective was to determine whether a portion of the phosphate could be recovered in a grade suitable for treatment with phosphoric acid to produce 45 pct superphosphate. The ore consisted of variably cemented sand interlayered with clay. The sand layers were composed of grains of quartz, phosphate, and clay embedded in a matrix of clay and phosphate. Some clay was finely disseminated in the phosphate grains. Little massive high-grade phosphate was present. The material used in the flotation tests was a washed sand that had been separated from the ore in a bowl classifier at the TVA phosphate-washing plant. The percentage composition of the sand was as follows: P2O5, 20; SiO2, 40; CaO, 29; Fe2O3, 2; Al2O3, 3; F, 2.3. The particle-

Jan 1, 1948

By Theo B. Comstock

TO the large majority of visitors the unique features of the National Park are interesting chiefly on account of their novelty. Scientists of all schools may find here food for reflection, and much that is rare and marvelous; but the real, practical uses of the reservation, aside from its pleasure-giving adaptations, are not as yet fully appreciated. Since 1873, the writer has on frequent occasions expressed freely his own views upon the proper means of utilizing the Park for the best interests of science.* Some of the recommendations made have been adopted by the authorities. At the suggestion of friends I present here a brief statement of facts concerning matters which may be of advantage for visiting engineers to know, hoping that the very limited stay of the Institute may thereby be rendered a little more profitable, and that our common profession may possibly receive some benefit. First, then, it should be understood that, as in many other cases in. the West, the present routes to the Park from the south are not the most direct. The expedition of Captain (now Major) Jones in 1873 discovered a practicable route for a, wagon or railroad via the head of Wind River, through To-gwo-tee Pass and Two-Ocean Pass, by which the distance from Point of Rocks, Wyoming, on the Union Pacific R.R., to the Yellowstone Lake, is only 290 miles. Eventually, it is probable that a railway line from Cheyenne or some other point in Wyoming will be constructed, which, taking advantage of

Jan 1, 1888

By M. C. Udy, P. C. Rosenthal

THE use of minute boron additions to steel has been given considerable attention in recent years. Comparisons made between boron-free and boron-containing heats of otherwise identical analysis have indicated, beyond a doubt, the potent effect of boron for increasing hardenability. The actual hardenability increase has been expressed as a multiplying factor, or in terms of the percentage of other alloying elements boron might replace, The present study presents the results of a systematic survey of. the use of boron as an addition to two types of alloyed steels and as a replacement for various percentages of molybdenum in these steels, Both cast and wrought steels of the two basic compositions were prepared. Molybdenum, because of its scarcity at the time the investigation was started, was selected as the element to be replaced by boron. Attention was also given to the effects of boron on other properties of the steels, particularly their notched-bar toughness, to investigate other advantages or limitations of this element as an alloy addition. EXPERIMENTAL WORK Steels Investigated The two basic compositions used in this survey of boron as a replacement for molybdenum are given in Table I. The cast steels were higher than the wrought steels in silicon content to improve the casting quality. [ ] Each of these base steels, both cast and wrought, was made with molybdenum contents of o, 0.10, 0.20, 0.30, or 0.40 per cent, the total comprising 20 steels. In addition, each of these 20 compositions . was prepared with boron additions in amounts of 0.0015, 0.003, and o,006 per cent as ferroboron; and in amounts of 0.002 and 0.005 per cent as two com¬mercial intensifier alloys, designated alloys A and B. The boron-treated steels totaled 100, and the entire series 120, Test Procedure Each steel was melted as an individual heat in a 50-lb., magnesia-lined induction furnace. Ingot iron scrap or mixtures of ingot iron and steel scrap were used for melting stock. Deoxidation was carried out in the furnace with o.10 per cent aluminum. The aluminum addition was

Jan 1, 1946

By Walter Harvey Weed

The notes given in this paper, the result of observations made during recent brief professional trips to the northern States of Mexico, are offered as a slight contribution to the geological knowledge of a region little known, but long famous for its rich gold- and silver-mines. They are not detailed geological studies, but they contain, I believe, the salient facts. The following districts were visited: 1. Santa Eulalia (silverlead) ; 2. Parral (silver-lead); 3. Las Vigas (copper); 4. Jimenez (copper); 5. Guadalupe y Calvo (gold); 6. La Cumbre (gold); 7. Palmarito (silver); 8. Cananea (copper); 9. Sierra Pinitos (gold); 10. Sierra Azul (gold). 1. The Santa Eulalia Silver-Lead Deposits. Seventeen miles SE. of Chihuahua is the mining district of Santa Eulalia, to which that city owes its origin and long prosperity. Discovered in 1703, this district has been, and still is, one of the great silver-lead producers of the world. For 86 years after its discovery, the total output upon which the crown tax was paid amounted to $112,000,000. Worked until within the last 20 years by the most primitive methods, without machinery of any kind, the deposits continued to yield a vast treasure of silver; at present the yearly tonnage far exceeds that of former times. A broad-gauge road runs from Chihuahua up the valley of a small creek to the village of Santa Eulalia, which is situated within the borders of the mountains of that name. A few miles out of Chihuahua a narrow-gauge railway, owned by the Chihuahua Mining Co., branches off to the mines. This road ascends a smooth but steeply-rising plain to the base of the mountains, and winds about the slopes until the mines are

Jan 1, 1902

By Arthur W. Sheafer

MR. ECKLEY B. COXE, in his able and interesting paper on " The Preparation of Small Sizes of Anthracite,"* read and discussed at the Glen Summit Meeting, October, 1891, refers to the reputed immense amount of coal contained in the culm-banks, which are the unsightly accompaniment of every mining operation in the anthracite coal-regions. Mr. Coxe thinks the available amount and value greatly exaggerated, giving among his reasons (1) the spoiling of the culm by mixing with other refuse; (2) its deterioration; (3) its destruction by fire ; and (4) frequent failures to realize expectations as to the size of the banks. These points are undoubtedly important factors in determining the advisability of working any individual bank, but they have a varying influence in the several regions, some prevailing more in one than in another. Although the amount of fuel lying waste in these banks is still an uncertain and undetermined quantity, yet no one can visit the Schuylkill region without being impressed with the fact that a considerable amount of culm, too valuable to be left merely to the mercy of the elements, surrounds and encumbers each site of an old or present colliery operation. The rapid increase in the number of washeries, and the demand for leases on old culm-banks, shows that, in the Schuylkill region at least, the question of deterioration doès not play an important part. The proportion of coal to refuse, the relative percentage of the sev-

Jan 1, 1895

By Richard M. Foose

Most of the roofing granules produced in Pennsylvania are made by two companies at three plants. The Advance Industrial Supply Co. has three quarries and a mill at Gladhill Station, in southern Adams County. The Funkhouser Company is actively engaged in mining, quarrying and milling at Charmian, about one mile west of Gladhill Station, and at Delta, in southern York County. These three plants produced approximately 100,000 short tons of granules in 1943. The production of rooling granules in 1937 for the whole country was only about 500,000 tons, generally indicating the large growth of the industry since that time. The fundamentals of producing roofing granules were discussed comprehensively by G. W. Josephson in a paper before the Industrial Minerals Division in October 1943 (TP 1725, this volume page 460). The purpose of this paper is to describe the actual methods of mining the rock and milling it to make roofing granules, as practiced by the three Pennsylvania plants. Mining and Milling Funkhouser Company (Delta) The Funkhouser Company, near Delta, in southern York County, Pennsylvania, operates three joined quarries and a mine in the Peach Bottom slate. The joined quarries extend 1200 ft. in a northeast-southwest direction along the strike of the slate cleavage and are about 200 ft. .wide. The working face is about 45 ft. high. The quarrying operation is rather simple: Ingersoll-Rand Jackhamers, I-in. and 1 1/4-in., with hollow drill steel, are used to undercut the quarry face with 10-ft. holes. The face is "blown" and allowed to slump on the quarry floor. Loaded by a Marion electric shovel into trucks, the shattered rock is taken to the primary crusher 2500 ft. away. In addition to the normal quarrying operations, a drift into the northeast wall of the middle quarry was begun about 1935, and has advanced about 2000 ft. since then. Rooms have been driven at angles to the drift along choice beds of slate. The drifts and rooms have a roof more than 35 ft. high and the main drift and rooms are all more than 40 ft. wide. There is no cribbing at any place in the mine. Several of the rooms were driven upward on a 5' slope and in some of them there was stop-ing. Ingersoll-Rand Jackhamers are used, and only wet drilling is practiced. When visited in January 1940, an electric shovel was operating at the head of the drift, scooping up the slate blasted out of the working face. This, too, is trucked to the primary crusher. Some of the better quality slate is saved for making slate shingles. The primary crusher, which is a No. 30 McCulley gyratory, receives the slate from the trucks and crushes it to about a-in. size (Fig. I). This product travels by a 30-in. belt conveyor to Niagara vibrating screens with 2-in. holes. The minus a-in. product moves to a storage silo by bucket

Jan 1, 1948

By Richard M. Foose

Most of the roofing granules produced in Pennsylvania are made by two companies at three plants. The Advance Industrial Supply Co. has three quarries and a mill at Gladhill Station, in southern Adams County. The Funkhouser Company is actively engaged in mining, quarrying and milling at Charmian, about one mile west of Gladhill Station, and at Delta, in southern York County. These three plants produced approximately 100,000 short tons of granules in 1943. The production of rooling granules in 1937 for the whole country was only about 500,000 tons, generally indicating the large growth of the industry since that time. The fundamentals of producing roofing granules were discussed comprehensively by G. W. Josephson in a paper before the Industrial Minerals Division in October 1943 (TP 1725, this volume page 460). The purpose of this paper is to describe the actual methods of mining the rock and milling it to make roofing granules, as practiced by the three Pennsylvania plants. Mining and Milling Funkhouser Company (Delta) The Funkhouser Company, near Delta, in southern York County, Pennsylvania, operates three joined quarries and a mine in the Peach Bottom slate. The joined quarries extend 1200 ft. in a northeast-southwest direction along the strike of the slate cleavage and are about 200 ft. .wide. The working face is about 45 ft. high. The quarrying operation is rather simple: Ingersoll-Rand Jackhamers, I-in. and 1 1/4-in., with hollow drill steel, are used to undercut the quarry face with 10-ft. holes. The face is "blown" and allowed to slump on the quarry floor. Loaded by a Marion electric shovel into trucks, the shattered rock is taken to the primary crusher 2500 ft. away. In addition to the normal quarrying operations, a drift into the northeast wall of the middle quarry was begun about 1935, and has advanced about 2000 ft. since then. Rooms have been driven at angles to the drift along choice beds of slate. The drifts and rooms have a roof more than 35 ft. high and the main drift and rooms are all more than 40 ft. wide. There is no cribbing at any place in the mine. Several of the rooms were driven upward on a 5' slope and in some of them there was stop-ing. Ingersoll-Rand Jackhamers are used, and only wet drilling is practiced. When visited in January 1940, an electric shovel was operating at the head of the drift, scooping up the slate blasted out of the working face. This, too, is trucked to the primary crusher. Some of the better quality slate is saved for making slate shingles. The primary crusher, which is a No. 30 McCulley gyratory, receives the slate from the trucks and crushes it to about a-in. size (Fig. I). This product travels by a 30-in. belt conveyor to Niagara vibrating screens with 2-in. holes. The minus a-in. product moves to a storage silo by bucket

Jan 1, 1948

Harry HaRkness Stoek, whose sudden death on March 1,1923, was a great shock to his friends in all park of the country, was a man of remarkable personal characteristics and mental ability. Through an acquaintance with him of nearly 35 years, during 12 yeam of which I was intimately associated with him both in business and socially, I learned to appreciate his many high qualities, his strict adherence to high professional and social ideals, and his lovable traits of character. In this appreciation I was joined by every one who was thrown in close personal contact with him. He was a conscientious student, not given to hasty judgments, but when he formed an opinion he was positive in upholding it. At the same time, he was most courteous and kindly in combatting that which he believed was erroneous. In fact, I never knew a person of his attainments more modest, forceful and kindly, or one who had a keener sense of clean humor. In his private life,he was a devoted husband and father, a consistent communicant and worker in the Episcopal Church, and was charitable in all things. In fact, his whole life was marked by helpfulness to others and a determined and successful effort to "make the world better by his having lived in it." Doctor Stoek was born in Washington, D. C., Jan. 16, 1866. His early education was obtained in the public schools of that city and he graduated from the Central High School in the first class to graduate from a high school in Washington. He entered Lehigh University in 1883, graduated in 1887 with the degree of Bachelor of Science, and after a year of post-graduate study in mining and metallurgy he received the degree of Engineer of Mines. During the summer vacation in 1885, he served as an assistant in the Department of Mineralogy in the National Museum at Washington, and during the summer of 1887 acted as U. S. Government inspector of dredging on the Tharnes River, Connecticut. From June, 1888, to January, 1900, he was assistant engineer for the Susquehanna Coal Co., at Wilkes-Barre, Pa. From January, 1890, to June, 1893, he was Instructor in Mining, Metallurgy and Geology at Lehigh University, and had charge of all courses in mining and metdlurgical design, and the visits of students to mines and metallurgical

Jan 1, 1923

Harry HaRkness Stoek, whose sudden death on March 1,1923, was a great shock to his friends in all park of the country, was a man of remarkable personal characteristics and mental ability. Through an acquaintance with him of nearly 35 years, during 12 yeam of which I was intimately associated with him both in business and socially, I learned to appreciate his many high qualities, his strict adherence to high professional and social ideals, and his lovable traits of character. In this appreciation I was joined by every one who was thrown in close personal contact with him. He was a conscientious student, not given to hasty judgments, but when he formed an opinion he was positive in upholding it. At the same time, he was most courteous and kindly in combatting that which he believed was erroneous. In fact, I never knew a person of his attainments more modest, forceful and kindly, or one who had a keener sense of clean humor. In his private life,he was a devoted husband and father, a consistent communicant and worker in the Episcopal Church, and was charitable in all things. In fact, his whole life was marked by helpfulness to others and a determined and successful effort to "make the world better by his having lived in it." Doctor Stoek was born in Washington, D. C., Jan. 16, 1866. His early education was obtained in the public schools of that city and he graduated from the Central High School in the first class to graduate from a high school in Washington. He entered Lehigh University in 1883, graduated in 1887 with the degree of Bachelor of Science, and after a year of post-graduate study in mining and metallurgy he received the degree of Engineer of Mines. During the summer vacation in 1885, he served as an assistant in the Department of Mineralogy in the National Museum at Washington, and during the summer of 1887 acted as U. S. Government inspector of dredging on the Tharnes River, Connecticut. From June, 1888, to January, 1900, he was assistant engineer for the Susquehanna Coal Co., at Wilkes-Barre, Pa. From January, 1890, to June, 1893, he was Instructor in Mining, Metallurgy and Geology at Lehigh University, and had charge of all courses in mining and metdlurgical design, and the visits of students to mines and metallurgical

Jan 1, 1923

By John S. Johnson

The maintenance cost, or renewal cost, in any preparation plant is a large item of expense and reflects in the total cost of producing and preparing the ton of coal. It is given constant study to the end that ways and means of controlling and reducing this proportion of the total cost may be developed. Study of this item of cost has proceeded along usual lines, which are: proper functioning of the maintenance organization; systematic and thorough inspection to prevent breakdonns; the making of repairs before renewals are needed; maintenance work done thoroughly the first time, instead of patching, study of parts needing frequent renewal or repairs or conditions resulting in delays, thorough knowledge of cost by the mall responsible for maintenance; and the use of special equipment and materials. This paper is to deal with special equipment and materials to reduce the maintenance cost hut before going into that I want to express an opinion on the general subject. Maintenance Organization Usually maintenance is taken care of by a group of men who perform their work on the off shift. The work is arranged by the operating official who should be thoroughly familiar with maintenance, so that materials needed may be made up for the particular job and waste of time in looking up materials be prevented. To perfect the maintenance organization, all operating attendants should be thoroughly trained to be familiar with all working parts of their equipment, to make a thorough inspection and to write out the slip for the work required. This requires job analysis, but it is worth the effort, because the attendant usually is better informed than anyone else about his particular equipment. The operating official can judge the scope of the work to direct the repair and to have material ready. Lubrication is an important item in maintenance, and a subject by itself. Usually the breaker oiler is designated to perform this task. This man should be picked for his ability and put in line for promotion to machinist. He should be trained as an inspector, as he is constantly visiting most parts of the breaker and has an opportunity to observe needed maintenance. The first thing is to lay out maintenance work and arrange to have it done; the next is to check the work and see that it has been properly done. This check should be made by the operating official, and through the attendant. The cost statement showing the various items of maintenance cost is not often understood by the man in direct charge. Cost sheets should be simplified and worked up by breaker sections; e.g., the cost of

Jan 1, 1947