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PROF RICHARD ÅKERMAN Stockholm, Sweden ANDREW CARNEGIR New York, N.Y. DR. JAMES DOUGLAS New York, N.Y. PROF HATON DE LA GOUPILLIERE Paris, France PROF HANS HOEFER Leoben, Austria PROF HENRI LOUIS LE CHATELIER Paris France M FLORIS OSMOND Paris, France JOHN E. STEAD Middlesborugh, England PROF DIMITRY CONSTANTIN TSCHERNOFF St Petersburg, Russia CHARLES D WALCOT Washingtion D.C.

Jan 1, 1910

H. RIES, Ithaca, N. Y.-The part of Mr. Fiske's paper that interests me especially is that portion dealing with the raw materials, and the tests that were applied to the raw materials in order to determine their value in advance, if possible, because that, I believe, is a step in the right direction. For a number of years I have done my best to persuade different consumers of clay to develop standard methods for testing raw materials. We have in this country a large variety of clays which can be used for a great many different purposes, but in many cases the consumers either have no standard methods for determining the value of those clays in. advance, or if they have they do not publish them; consequently it often puts the clay miner at a disadvantage. If, for example, manufacturers of different types of refractory materials would state publicly just what physical tests their raw materials have to meet, it would, I believe, help them to find more easily the materials that they are looking for, and the clay producer would also be benefited. It would also encourage him to have his clays tested in advance, so that samples could be accompanied by certificates of physical tests that would be of convenience to the manufacturer. At the present time, in this country there are certain types of clay which seem to be rather scarce. There apparently are not many deposits of clay that are exactly suited for the manufacture of zinc refractories. So, too, there are not many deposits of clay that are suited for the manufacture of glass-pots, or the blocks for glass tank furnaces, or clays that can be used for graphite crucibles. Now, in many cases, no standard series of tests has been developed. I am also gratified to see that Mr. Fiske considers the tensile strength. tests of value. Some years ago the American Ceramic Society appointed a committee to draw up a series of recommendations covering standard tests. These recommendations were especially for the use of State geologists and the U., .S. Geological, Survey. Among the tests that were considered was the tensile-strength test, which Mr. Fiske has mentioned in his paper. Unfortunately, a majority of the committee turned it down, and the test was therefore not officially approved, but two of us, who formed the minority, believed in it. Since then the other members of the Committee have come to see that that is an important test to make and Mr. Fiske has emphasized it in his paper.

Jan 1, 1918

By J. F. Havard

Gypsum is a useful industrial mineral found abundantly on the earth's crust. It is inexpensive to mine and process, and its calcined products have a wide range of readily controllable properties such as strength, density and setting time. It has proven to be such a useful material indeed, that ten American companies, operating some 57 calcining plants in 25 states in 1958, produced or imported in that year a total of 13,649,000 tons of the crude mineral valued at $39,361,000, which they then converted into manufactured products with a value of $329,070,000. Gypsum (CaSO4.2H2O) is calcium sulfate with two molecules of combined water, which are responsible for most of its useful properties. It is closely associated in most deposits with anhydrite (CaSO4), which contains no combined water and has limited commercial value in the United States. Man has long recognized the useful qualities of gypsum. It was utilized by the Egyptians in the construction of the pyramids and, later, by the Romans for important structures. Many of the ancient peoples prized gypsum for artistic and ornamental purposes, carving statuary from alabaster and making casts with plaster. The tabular variety, selenite, was used for windows, and the light transmitted through these windows reminded people of light from the moon (selene), hence the name selenite. The use of gypsum continued through the Middle Ages and into modem times. Benjamin Franklin was a famed exponent of gypsum because he applied ground gypsum to clover fields in the form of large letters which later read, in the more luxuriant growth, "land plaster used here." Gypsum is still used as an effective conditioner for some soils, but in recent decades, particularly in North America and Europe, it has become much more important as a major material for the building industry. Description Gypsum and anhydrite are closely associated minerals. Gypsum is found in a number of forms: massive rock gypsum, alabaster, selenite, satin spar, and gypsite. Anhydrite is found as massive rock or as smaller bodies or isolated crystals included in gypsum. Massive Rock Gypsum comprises most of the commercial gypsum and occurs as a sedimentary rock, interbedded in most places with shale, limestone or dolomite. This rock is soft and crystalline. Its color is white or shades of gray, pink, yellow, brown or other colors. Alabaster is a pure, compact and fine-grained variety suitable for use in sculpture or turning into artistic forms; it may be white or selected for attractive coloration. Selenite is gypsum crystallized in flat, transparent, flexible foliated plates, found in clays or in surface vugs in gypsum. Satin Spar is a fine silky fibrous variety with the axes of the crystalline fibers perpendicular to the vein or joint in which it has formed. Gypsite is an earthy mixture of gypsum with clay and sand in secondary formations; it is sometimes useful as a soil conditioner and has been used in making base-coat plasters. Pure gypsum contains 20.9 pct combined water, 46.6 pct sulfur trioxide (SO3) and 32.5 pct lime (CaO). Standard specifications (American Society for Testing Materials Designation C 22-50) read that minimum purity for material to be called gypsum is 70 pct CaSO4.2H20. Most of the commercial gypsum is 85 to 95 pct pure as produced. Impurities in

Jan 1, 1960

President MRS. FREDERICK LAIST 24 Tompkins Road Scarsdale, N. Y. First Vice-president MRS. LOUIS D. HUNTOON Pleasantville New York Second Vice-president MRS. REED W. HYDE 84 Mountain Avenue Summit, N. J. Third Vice-president MISS MADELINE P. STONE 49 West 11th St. New York, N. Y. Fourth Vice-president MRS. JOHN J. LINCOLN Elkhorn, McDowell Co. West Virginia

Jan 1, 1932

Although the Suggestions to Institute Authors, as revised and amplified over the years to meet changing conditions and experience, have had as their primary objective the guidance of the author who is preparing a paper for record in the TRANSACTIONS, there are in this current version many excellent suggestions for the preparation of any material for publication by the Institute In this connection it should be emphasized that in a sense, and to a degree determined by the editors, the Institute has in its journals "a place for everything," especially a place for the article of practical nature that is of immediate but not necessarily permanent interest Such articles may be referred by the Institute Technical Publications Committee to the editors or submitted directly to them , [Papers (TECHNICAL PUBLICATIONS and TECHNICAL NOTES) authorized for the TRANSACTIONS are, with the discussion, gathered together at the end of the calendar year and with a table of contents and index, bound, according to Branch classification, as volumes of the TRANSACTIONS

Jan 1, 1952

By AIME AIME

A separate room in the suite occupied by the American Institute of Mining Engineers on the ninth floor of the United Engineering Society Building, has been equipped with furniture and telephone extension for the temporary use of members of the Institute or of sister societies, or visitors suitably accredited. In addition to this general accommodation, another room has been similarly furnished as a business headquarters for a single person, and for a limited period. For the conditions of this privilege, inquiry should be made at the office of the Institute. In order that the benefit of this arrangement shall not be restricted to a few members only, the period of continued occupancy will be limited, and applications will be considered in the order of their receipt. A small fee will be required for the use of the facilities furnished.

Jan 1, 1908

By John H. Smith

Because of increased pressure from federal and state regulatory agencies, most acid flows will require some sort of treatment prior to being discharged to receiving streams. In many industries, the volumes of liquors are large and their acid content varied. Development of a waste treatment process minimizing equipment cost and utilizing land efficiently is mandatory. Methods of acid neutralization with lime have been known for years, however, the volume and characteristics of the resultant precipitated solids can create a disposal problem. Also, when standard lime treatment is used, the settling characteristic of the precipitated solids is normally slow. In some instances, the necessity of added dissolved solids removal, such as iron, needing aeration, add to the problem of concentrating neutralized solids.

Jan 12, 1972

By J. Parke Channing

THE production and use of copper in the world, like that of other metals, has been of slow growth. In 1880, production in the United States, was only about 60,000,000 lb. and the world's production 325,000,000 lb. Up to 1913 there was a gradual and regular increase in production; in 1912 the production was 1,250,000,000 lb. for the United States and 2,200,-000,000 lb. for the world. At the outbreak of the war there was a slight falling off, both in the United States and elsewhere, but when it was realized that the war was not to be a short one and that copper was one of the most important things for carrying it on, there was a tremendous increase in production every-where. Roughly speaking, the average production for the years 1916, 1917 and 1918 was very close to two billion pounds in the United States and three billion pounds in the world. WAR DEMANDS STIMULATED PRODUCTION Not only did the production of copper in the United States increase, but the same may be said of .all the base metals, particularly of zinc. Much of the zinc used by the Allies came from Australia, but had been smelted in Belgium and Germany, now closed to them. We were called upon to make good this lost supply and in feverish haste built new zinc smelteries and opened new mines. The armistice found the United States with a large surplus of copper on hand, variously estimated at from 800,000,000 to 1,000,000,000 lb. In addition to this surplus in the United States, there were considerable stocks in the hands of the Allies and also immense quantities of unused brass. To. complicate the situa-tion still further, the reclamation of old brass shell cases and other used material was instituted, still further curtailing the demand for new material. This situation was- not appreciated at the time and it was assumed, that the Central Powers would immediately come into the market ? replenish their exhausted stock of copper. During the war Germany had torn down copper trolley wires and roofs, and melted up bronze bells, doors, statues and other copper-bearing material to reclaim this metal for military purposes. But Germany-was unable or at least unwilling immediately to replace her copper substitutes.

Jan 1, 1923

By H. W. Mead, C. E. Birchenall

SELF-DIFFUSION of cobalt has been investigated by Ruder and Birchenall,1, 2 Nix and Jaumot,3 and Gruzin.4 The results for a given tem- perature differ by a factor of about six in the extreme cases with no really close agreement between any two sets of data. The first two groups of investigators employed the decrease of surface activity method. Since Ruder and Birchenall have shown that the values obtained from this method are sensitive to the surface preparation, it seemed desirable to perform a few check experiments by a method not open to this objection.

Jan 1, 1956

By A. W. Schlechten

The proposition is advanced that edutcation specifically for exlractive metallurgy is desirable not because the course content is cmique but rather as a means of indoctrinating the student with a backgrocmd that will give him an interest and pride in the profession. Factors that have caused the decline in enrollment in metallurgical engineering courses emphasizing extractive processes are being overcome. There is a need to distinguish between the sciences of metallurgy and the engineering applications to avoid confusion both in and out of the profession. AS a first step in preparing the 1967 EMD Lecture I searched the literature to determine what my predecessors had done hoping thereby to gain some clues for my own performance. The Transactions of the Metallurgical Society show that the first EMD Lec- turer in 1959 was Dr. W. J. Kroll, known chiefly today for his pioneering work on the production of titanium and zirconium, but equally respected by an earlier generation for his contributions to lead refining. He has been followed by a series of well-known and competent metallurgists all possessing specialized knowledge that has served as a basis for their lectures. The EMD Lectures have in general been a review of the development of a certain aspect of the extractive metallurgical industry or a preview of a particular area of science or technology that has applications in extractive metallurgy. The usual format is to describe developments of the past, summarize the present state of knowledge, and make predictions for the future. There has been great variation in the relative amount of time devoted to these three subdivisions, the past, the present, and the future. For example, Professor Gaudin, the 1961 EMD Lecturer, in speaking of Separation Engineering on the Moon, did not have too many examples of past practice and so had to emphasize the future. It is cheering to observe that all of these authorities were optimistic in their predictions. Despite the fact that four of the previous EMD Lecturers have been educators, Professors Gaudin, Pidgeon, Schuhmann, and Kellogg, none of them discussed the subject of education for extractive metallurgists. I might say parenthetically that lecturers in other divisions, such as B. M. Larsen, J. B. Austin, F. D. Richardson, John Chipman, and R. F. Mehl, have commented with concern on the present state of training for extractive metallurgy. What can you say that is new about extractive metallurgy education? Certainly nothing new can be said about the educational process itself. Professional educators do have new approaches to teaching and learn-

Jan 1, 1968

T. R. HARRISON, Washington, D. C. (written discussion *).-Ad-vantage will be taken of this occasion to mention briefly a form of double potentiometer which has been used at the Bureau of Standards for about 2 1/2 yr. in calibrating thermocouples. The calibrations referred to are those made by comparison to standard couples. In order to insure equality of temperature between the couples, the junctions are fused together; consideration of fundamental principles will show that this introduces no error. Two separate potentiometers are used, one connected to each thermocouple, and each potentiometer is provided with a reflecting galvanometer. The two spots of light are reflected on to a single scale, the galvanometers being set in such a position that the spots coincide on the scale at a point marked zero when the circuits are open or when the potentiometers are balanced. By setting one potentiometer to a desired value and adjusting the other so that both spots pass across the scale together as the temperature rises or falls, simultaneous readings are obtained. By making observations first with a rising temperature and then with a falling temperature, the rates of rise and fall being approximately equal, and taking the means of the results found, several minor errors such as those clue to differences in the time lags of the two systems, etc., are eliminated or greatly reduced. The differences between the values

Jan 12, 1919

By J. J. Bodmer

In 1855, Franz Uchatius patented, in England, his process of manufacturing cast steel. The first experiments, on a practical scale, were made at the Ebbw Vale Iron Works, Monmouthshire. The charge consisted of a mixture of cast iron with about 20 per cent. of a pure iron ore, and with or without other ingredients. In order to obtain the cast iron in a subdivided condition, Uchatius granulated molten pig-metal by running it into water, which during the operation was kept well agitated, and found that "the finer the iron is granulated, the softer will be the resulting steel." The writer is not aware that granulated iron has been used practically, otherwise than in the above-named process; and until 1866 no other process of subdividing iron than by granulation was known. In April, 1866, an English patent was obtained by the writer for subdividing blast-furnace and other slags and metals in a molten condition, by passing the same through one or more pairs of rolls. In reference to iron the idea was, in following up the direction pointed out by the Uchatius process, to obtain better results in the puddling process by means of a thorough amalgamation (not simply a mixture) of the iron with the oxides and other ingredients in the charge itself. Experiments were made. A quantity of iron direct from the blastfurnace was subdivided (or laminated) by passing it through a pair of plain rolls. The rolls were hollow, and water was made to pass through them to keep them sufficiently cool. Without giving differential speed to the rolls, sheets were obtained about one-sixteenth inches thick, and from about one hundred square inches surface, downwards. With differential speed, the iron falls from the rolls in

By Howard A. Meyerhoff

In western Argentina, in the Province of Mendoza and the Territory of Neuquen, there is a series of solid bitumen deposits which are claimed to be the most extensive in the world. In a linear belt 500 km (311 miles) long, roughly paralleling the axis of the Andes but occupying a variety of positions with respect to the orogenic structures, more than 100 outcrops have been reported. Approximately 70 of these have been prospected, and some mining has been planned or attempted for about half this number. Limited tonnage, high sulphur content, inaccessibility, labor shortages, and disastrous fires have taken a heavy toll among these operations, and in 1947, only 4 deposits were being actively mined, but 8 more were being explored and developed with a view to placing them in production. Inasmuch as these deposits are currently yielding a substantial fraction of Argentina's limited domestic supply of solid fuels, a brief account of the deposits and of the small industry based upon them will provide a commentary on Argentina's fuel problem. Character of Solid Bitumens The solid bitumens of Mendoza and Neuquen are petroleum derivatives, as is indicated by the following ultimate analysis : Constituents Per Cent Hydrogen.................... 6.8 Carbon...................... 82.4 Nitrogen..................... 1.6 Oxygen...................... 2.7 Sulphur...................... 2.2 Ash.......................... 4.3 100. 0 In physical appearance they bear a close resemblance to coal and are commonly called carbon. Their specific gravity has an extreme range of 1.10 to 1.777 in 36 samples weighed, but the average is between 1.14 and 1.24. The material is black, lustrous to dull, with blocky to sub-con-choidal fracture. Though brittle, the purest material is softer than anthracite and exhibits slightly more cohesion. This bituminous material is generally known as asfaltita or asphaltite, but definitive chemical studies indicate that the term asphaltite or grahamite can be applied correctly only to the exceptionally pure material of the Auca Mahuida district in Neuquen. Some other name should be used for the chemically variable bitumens found in all other districts, and the designation "asphaltitic pyrobitumen" has been proposed by Carlos A. S. Piscione.1 At the present time these bitumens are finding favor as solid fuel and as a gas-producing medium. They yield heat values of 8650 to 9750 cal,2 or 14,500 to 16,750 Btu per pound, and in consequence of their excellent heating qualities and the scarcity of imported coal, they are marketed as far away as Buenos Aires at a price of go to 95 pesos, or approximately $22 to 23, per metric ton. In burning, the material swells and decomposes into solid, fluid, and gaseous fractions which burn violently though nonexplosively. Its combustibility has been responsible for disasters and virtually complete destruction at Mina La Es-peranza and Mina Santa Marta, and for minor mishaps elsewhere, as at Mina Escondida in August 1947.

Jan 1, 1949

By Koehler S. Stout

At today's mineral prices, unproductive or low productive work in any underground mine must be kept at a minimum to insure a profit. Improper level and raise spacing can be one of the contributing factors to high production costs, and little can be done to reduce these costs after the spacing interval has been chosen. The objective in selecting level spacing is to find the most desirable interval which produces ore at the least cost per ton while still operating within the highest margins of safety and efficiency to the workmen. In addition, maximum possible recovery of ore under the conditions must be attained.

Jan 11, 1962

By W. C. Muehlhof, L. D. Lamont

THROUGHOUT the anthracite industry's history, the problem of handling and dis¬posing of refuse material has been one of major importance. In the early days of the industry's activities, only the large sizes of anthracite were satisfactory for market requirements and the smaller sizes were deposited as refuse. As time went by, more efficient coal-burning equipment was developed and a market demand was created for the finer sizes of coal. This demand made it possible to recover market¬able coal from banks deposited as refuse in the earlier days of mining. The same condition holds good today and we can see a definite trend toward the objective of utilizing the No. 4 and No. 5 buckwheat sizes. Under present conditions, we know that a limited market exists for No. 4 and 5 buckwheat; we know that the finer sizes of anthracite can be burned as pulverized fuel; we know that these fine sizes can be processed and sold as bri¬quettes, and we also know that the heat content of these fine sizes of coal is compar¬able with that of the sizes now merchan¬dized. Therefore, it should be the objective of the industry to conserve these fine sizes of coal in such manner that if and when processing facilities are developed, and market demands exist, the material can be salvaged and made available to meet these demands. From the standpoint of economical future reclamation, the ideal method of disposing of refuse containing the finer sizes of coal is to deposit it in banks separate and apart from other breaker refuse. By this procedure, the minimum amount of material will be processed in future salvage operations to recover the No. 4 and No. 5 buckwheat sizes. Many collieries in the anthracite region are operated under leases that have a specific term. These lease agreements provide that, upon expiration of the lease by term, exhaustion or otherwise, the ownership of the refuse material reverts to the lessor. Therefore, a question was raised in the minds of these operators: Why should I assume the expense of such pro¬cedure when I have no assurance that I will benefit by the future processing and sale of these fine sizes? Under present conditions, the answer to this question is not one of choice but of necessity, as restrictions imposed by legislation make it mandatory on operators of preparation plants to take necessary steps to properly treat silt-laden waters before permitting them to enter the streams. By reason of these restrictions, the disposal of fine sizes becomes a secondary_ rather than a primary operating con sideration, and the procedure for disposing of this refuse becomes a matter of choice governed principally by topographical and geographical conditions. METHODS OF HANDLING REFUSE There are three principal methods of handling and disposing of fine-size refuse; namely :

Jan 1, 1946

President-Mrs Andrew E Beer, 25 Sutton Place at 58th Street, New York 22, N Y. First Vice-President-Mrs. Edward H Thaete, Schuyler House, Fort Hill Village, Scarsdale, N. Y. Second Vice-President-Mrs Michael L Haider, 3 East 84th Street, New York 28, N. Y. Third Vice-President-Mrs Stephen Krickovic, 2275 Country Club Drive, Bridgeville, Pa

Jan 1, 1960

PRESIDENT OF THE COUNCIL. D. W. BRUNTON DENVER, COLO. (Term expires February, 1911.) VICE-PRESIDENTS OF THE COUNCIL. W. C. RALSTON SAN FRANCISCO, CAL. W. L. SAUNDERS NEW YORK, N. Y. H. V. WINCHELL ST. PAUL, MINN.¬ (Term expires February, 1911.) BENJAMIN B. LAWRENCE NEW YORK, N. Y. JOSEPH W. RICHARDS SOUTH BETHLEHEM, PA. ALBERT SAUVEUR CAMBRIDGE, MASS. (Term expires February, 1912.)

Jan 1, 1917

PRESIDENT OF THE COUNCIL ROBERT W. HUNT CHICAGO, ILL. (Term expires February, 1907 ) VICE-PRESIDENTS OF THE COUNCIL WILLIAM P. BLAKE TUCSON, ARIL. THOMAS F COLE DULUTH, MINN. IRVING A. STEARNS WLKES-BARRE, PA. (Term expires February, 1907 ) HENRY M HOWE NEW YORK, N. Y. J. B GRANT DENVER, COLO. JAMES D HAGUE NEW YORK, N. Y. (Term expires February, 1909 )

Jan 1, 1910

By Howard A. Meyerhoff

IN western Argentina, in the Province of Mendoza and the Territory of Neuquén, there is a series of solid bitumen deposits which are claimed to be the most extensive in the world. In a linear belt 500 km (311 miles) long, roughly paralleling the axis of the Andes but occupying a variety of positions with respect to the orogenic structures, more than 100 outcrops have been reported. Approximately 70 of these have been prospected, and some mining has been planned or attempted for about half this number. Limited tonnage, high sulphur content, inaccessibility, labor shortages, and disastrous fires have taken a heavy toll among these operations, and in 1947, only 4 deposits were being actively mined, but 8 more were being explored and developed with a view to placing them in production. Inasmuch as these deposits are currently yielding a substantial fraction of Argentina's limited domestic supply of solid fuels, a brief account of the deposits and of the small industry based upon them will provide a commentary on Argentina's fuel problem. CHARACTER OF SOLID BITUMENS The solid bitumens of Mendoza and Neuquén are petroleum derivatives, as is indicated by the following ultimate analysis: [CONSTITUENTS PER CENT Hydrogen6.8 Carbon82.4 Nit.rogenI.6 Oxygen2.7 Sulphur2.2 Ash4.3 100.0] In physical appearance they bear a close resemblance to coal and are commonly called carbón. Their specific gravity has an extreme range of 1.10 to 1.777 in 36 samples weighed, but the average is between 1.14 and 1.24. The material is black, lustrous to dull, with blocky to sub-conchoidal fracture. Though brittle, the purest material is softer than anthracite and exhibits slightly more cohesion. This bituminous material is generally known as asfaltita or asphaltite, but definitive chemical studies indicate that the term asphaltite or grahamite can be applied correctly only to the exceptionally pure material of the Auca Mahuida district in Neuquén. Some other name should be used for the chemically variable bitumens found in all other districts, and the designation "asphaltitic pyrobitumen" has been proposed by Carlos A. S. Piscione.1 At the present time these bitumens, are finding favor as solid fuel and as a gas-producing medium. They yield heat values of 8650 to 9750 cal,2 or 14,500 to 16,750 Btu per pound, and in consequence of their excellent heating qualities and the scarcity of imported coal, they are marketed as far away as Buenos Aires at a price of go to 95 pesos, or approximately $22 to 23, per metric ton. In burning, the material swells and decomposes into solid, fluid, and gaseous fractions which burn violently though nonexplosively. Its combustibility has been responsible for disasters and virtually complete destruction at Mina La Esperanza and Mina Santa Marta, and for minor mishaps elsewhere, as at Mina Escondida in August 1947.

Jan 1, 1947

By Archer E. Wheeler, Milo W. Krejci

There are two general methods in use for the production of metallic copper from matte which are worthy of consideration : (1) the Welsh blister process, and (2) the converter process.' As practically all of the copper produced to-day is made in converters, we will give a brief outline of that process before proceeding with the special subject of this paper. Matte may be roughly defined as a mixture of the sulphides of copper, iron, nickel, silver, etc. In the converter process this is blown up to metallic copper in a modified type of Bessemer converter. The conversion of matte consists mainly in, (1) the removal of sulphur in the form of SO2, and (2) the slagging of the iron. With this brief statement we come to the two subdivisions of the process of converting mattes: Converting with acid linings. Converting with basic linings. Converting with Acid Lininys, This is carried out by lining the converter with siliceous rock or ore, which performs two functions: It protects the iron shell of the converter from the molten charge, and it furnishes the silica for combining with the iron as it is oxidized from the matte, to form a ferrous silicate. It follows from the second of these functions that this siliceous lining must be replaced from time to time, and in practice it has been necessary to reline converters every 8 to 40 hr., this time varying in different plants and even with different linings in the same plant, the life of a lining depending upon the grade of the matte treated, and upon the composition, the thickness, the tamping, and the drying of the lining.

Jan 1, 1914