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By Andrew B. Crichton

No more important question has come before the coal industry in the past decade than the prevention of stream pollution by mine drainage; especially in Pennsylvania, where large areas of coal land have been developed. It may be thought that the problem of labor or lack of transportation outweighs in importance that of stream pollution. We can see possible remedies for labor and transportation problems but there is no known satisfactory solution of the mine-drainage problem. The subject has been given little serious attention, for, until recently, it has been little understood; but in the past year it was brought to the attention of the coal-mining industry by the introduction, in Congress, of several bills designed to prevent the discharge of acid waters from mines or other sources into navigable streams, or their tributaries. The first legislation proposed was the Applebybill, H.R.7369, designed particularly to prevent the oil pollution of coastal waters. It contained the following provisions, which the coal men regarded as referring to the coal industry. It shall be unlawful to throw ... any refuse matter of any kind ... into any navigable waters of the United States or into any tributaries of any navigable waters from which the same shall float or be washed into such navigable waters. The chemical, steel, paper, and other manufacturing industries, as well as the mining industry, objected to this clause, the miners claiming that it would prevent the discharge of waste or mine drainage into any waters of the United States, for all streams or tributaries finally reach navigable waters. The next bill introduced was that of Congressman Briggs, H.R. 7430, an amendment to Section 13 of the Pollution Act of March 3, 1899. The original act referred chiefly to oil and oil refuse, but it provided also "that no material of any kind should be deposited on the bank of a navigable water, or tributary, which might reach the waters and interfere with or

Jan 1, 1923

By Lynn G. Howell, Alex Frosch

In a previous article1 we have described a technique for measuring the relative intensities of gamma rays from the radioactive elements occurring naturally in geological formations along the walls of a borehole. The apparatus consisted of two Geiger-Müller tubes mounted inside a pressure-tight chamber. Each counter tube was coupled separately to an amplifier and a frequency meter at the surface by means of a multiconductor cable upon which the chamber was suspended. The output currents of the two frequency meters were recorded on a photographic paper as the chamber was moved in the hole. These traces showed remarkable correlation with the geologic formations, as evidenced by comparison with commercial electrical logs.2 Owing to the penetrating power of the gamma rays, logs may be taken in both open and cased boreholes. The apparatus has recently been changed somewhat. One of the counter tubes has been removed and a stage of amplification has been added inside the chamber. This arrangement seems to give a more favorable signal-to-noise ratio and satisfactory logs can be now made in cased holes and also in open holes as previously. Briefly described, the chamber moving in the hole is made of 3½-in. drill pipe and is about 10 ft. long. There is an additional extension about 2 ft. long at the top, inside which cable connections are made. The Geiger-Müller tube is mounted inside the bottom end of the chamber. Above this is the vacuum-tube amplifier with its batteries and transformer. In the top part of the chamber, small 45-volt batteries are mounted, which in part supply the high voltage for the counter tube. Additional voltage is supplied from the surface through the multiconductor cable upon which the chamber is suspended. Also, the output of the transformer in the single-stage amplifier is coupled to another single-stage amplifier at the surface through this cable. The surface amplifier is coupled to the Thyratron-controlled frequency meter, the tank circuit of which consists of a one megohm resistor across which is a bank of condensers varying in

Jan 1, 1940

By Alex Frosch, Lynn G. Howell

In a previous article1 we have described a technique for measuring the relative intensities of gamma rays from the radioactive elements occurring naturally in geological formations along the walls of a borehole. The apparatus consisted of two Geiger-Müller tubes mounted inside a pressure-tight chamber. Each counter tube was coupled separately to an amplifier and a frequency meter at the surface by means of a multiconductor cable upon which the chamber was suspended. The output currents of the two frequency meters were recorded on a photographic paper as the chamber was moved in the hole. These traces showed remarkable correlation with the geologic formations, as evidenced by comparison with commercial electrical logs.2 Owing to the penetrating power of the gamma rays, logs may be taken in both open and cased boreholes. The apparatus has recently been changed somewhat. One of the counter tubes has been removed and a stage of amplification has been added inside the chamber. This arrangement seems to give a more favorable signal-to-noise ratio and satisfactory logs can be now made in cased holes and also in open holes as previously. Briefly described, the chamber moving in the hole is made of 3½-in. drill pipe and is about 10 ft. long. There is an additional extension about 2 ft. long at the top, inside which cable connections are made. The Geiger-Müller tube is mounted inside the bottom end of the chamber. Above this is the vacuum-tube amplifier with its batteries and transformer. In the top part of the chamber, small 45-volt batteries are mounted, which in part supply the high voltage for the counter tube. Additional voltage is supplied from the surface through the multiconductor cable upon which the chamber is suspended. Also, the output of the transformer in the single-stage amplifier is coupled to another single-stage amplifier at the surface through this cable. The surface amplifier is coupled to the Thyratron-controlled frequency meter, the tank circuit of which consists of a one megohm resistor across which is a bank of condensers varying in

Jan 1, 1940

By M. Muskat, H. G. Botset

Any information that will increase the accuracy of our knowledge of the conditions prevailing in petroleum reservoirs should be of direct value in the determination of the proper operating technique as well as in the estimation of reserves and of ultimate production. The obvious method of obtaining this information is by studying a sample of the reservoir rock and its contents. In any such study, the problem of primary importance and maximum difficulty is that of getting the core to the surface in such a manner that its original fluid content is undisturbed, which has so far proved to be an impossible task. Though it might be rash to say this will never be done, it is certainly safe to assume that a, method for the recovery of a core at the surface in its undisturbed original state may not be developed in the immediate future, and certainly will not be forthcoming without a great deal of costly experimentation. Therefore any information that may be obtained that will help to correlate the state of a core (its fluid saturation) at the surface with its condition at the time it was drilled should be of value to the petroleum industry. The experiments described in this paper were undertaken with the purpose of determining, if possible, any relationship that might exist between the saturation of a core at the surface and its original fluid content. No consideration has been given to the question of contamination by penetration of drilling water, since this problem has been extensively studied by other investigators.1-3 Furthermore, it was regarded as outside the scope of these experiments, which were concerned only with the effect of pressure reduction upon the liquid content of cores. In an experimental study of this sort involving a large number of variables, accurate control of all factors is very important. The essential and obvious procedure is to vary systematically one factor or condition while keeping all the others constant, which necessarily involves a rather protracted and sometimes tedious experimental program. The procedure adopted was essentially very simple, and consisted merely in filling a given core with fluid (gas and oil, gas and water, or

Jan 1, 1939

By R. M. Brick, M. A. Williamson

CERTAIN features of the response of copper and brass to deformation and recrystallization remain obscure. The textures obtained on rolled sheet are listed by Schmid and Boas1 as: No adequate explanation has been advanced for the presence of the secondary deformation texture of copper and its absence in brass or for the origin of the cubic recrystallization texture of copper.2 A recent publication3 attempted to rationalize the above empirically described annealing texture of brass on the basis of retention of the (110) [112] rolling orientation plus twinning about the central octahedral poles of the usual secondary (110) [115] orientation. The difference in the textures of annealed copper as compared to 70-30 brass is also shown by the difference in the position of ears for drawn copper, at o° and 90°, as compared with drawn brasses, at 45°, for all compositions between 90-10 and 70-30.4 Data on individual crystals are as yet too few to permit of an analysis of these textures comparable to that of mild steel as made by Barrett and Levenson.5 EXPERITMENTAL METHODS The materials studied included copper specimens cut from the central, equiaxed crystal portion of a tough-pitch wirebar; brass made from this copper and high-purity (99.99 per cent) zinc including alloys of 7 per. cent, 15 per cent, 24 per cent, 29 per cent and 36 per cent Zn and large single crystals of 70-30 brass. Sections ¼ in. thick of the cast polycrystalline copper and brasses were reduced 40 per cent by rolling, recrystallized to a common grain size of 0.045 mm. and then rolled directly to foil 0.002 in. thick. Hardness readings employing both the Vickers and Rockwell machines were taken at intervals during the reduction. For comparison, similar specimens were cross-rolled-i.e., turned through 90 for each pass-and comparable hardness data were secured. Finally sections from the single crystals of brass were cut to obtain the following initial orientations; these sections were rolled, hardness data secured and a complete micrographic record of structural changes obtained:

Jan 1, 1941

By M. Muskat, H. G. Botset

Any information that will increase the accuracy of our knowledge of the conditions prevailing in petroleum reservoirs should be of direct value in the determination of the proper operating technique as well as in the estimation of reserves and of ultimate production. The obvious method of obtaining this information is by studying a sample of the reservoir rock and its contents. In any such study, the problem of primary importance and maximum difficulty is that of getting the core to the surface in such a manner that its original fluid content is undisturbed, which has so far proved to be an impossible task. Though it might be rash to say this will never be done, it is certainly safe to assume that a, method for the recovery of a core at the surface in its undisturbed original state may not be developed in the immediate future, and certainly will not be forthcoming without a great deal of costly experimentation. Therefore any information that may be obtained that will help to correlate the state of a core (its fluid saturation) at the surface with its condition at the time it was drilled should be of value to the petroleum industry. The experiments described in this paper were undertaken with the purpose of determining, if possible, any relationship that might exist between the saturation of a core at the surface and its original fluid content. No consideration has been given to the question of contamination by penetration of drilling water, since this problem has been extensively studied by other investigators.1-3 Furthermore, it was regarded as outside the scope of these experiments, which were concerned only with the effect of pressure reduction upon the liquid content of cores. In an experimental study of this sort involving a large number of variables, accurate control of all factors is very important. The essential and obvious procedure is to vary systematically one factor or condition while keeping all the others constant, which necessarily involves a rather protracted and sometimes tedious experimental program. The procedure adopted was essentially very simple, and consisted merely in filling a given core with fluid (gas and oil, gas and water, or

Jan 1, 1939

By Helmut Thielsch

DURING the last three decades a great many arguments have been presented on the subject of "mosaic" or "block" structures of metals. Apparently because of insufficient evidence, the "block-structure" theories have never been widely understood among the physical metallurgists in this country, and most investigators among the few that have tried to demonstrate the existence of such an inner structure of crystals or grains have failed to recognize also the existence of a lamellar structure. Moreover, little thought has been given to justify the existence of such "lamellar" or "mosaic-block" structures on a theoretical basis. Since properties such as plasticity, ferromagnetism, hardness, diffusion, and others may be explained by structural faults in the lattice network of the crystals, the great importance of a more detailed knowledge of the structure within crystals or grains becomes now evident. Because of the vast extent of the field of submicroscopic structures, it shall be the purpose of this paper only to review the more important of the results obtained by other investigators, especially in Germany, where a great deal of attention has been given to mosaic structure during the last three years. The origin of this mosaic pattern f and effects of cold reduction and recrystallization will be shown in further studies later on. IMPERFECTIONS IN CRYSTALS The many terms used in the literature to denote structural types of crystals are often not clearly defined. To clear up some of the confusion, the meaning of the more important terms will be given here. Ideal, or Perfect Crystals.-Crystals without any structural imperfections are called "ideal crystals," or "perfect crystals," meaning a homogeneous interior structure of atoms, ions or molecules, as the case may be. In other words, at every point in the interior of the crystal exactly the same orientation of the crystallographic axes of the coordinate system would exist. The surface of such a body, if etched with an appropriate etching reagent, would reflect light with perfect uniformity. Crystals of this type are almost nonexistent. Real Crystals.-" Real crystals"' may contain various types of structural defects, which can be classified into: (I) lineage structure, (2) mosaic-block structure, (3) lamellar structure. The inhomogeneities existing in these groups mean that the orientation of the crystallographic axes will not be the same at every point within the interior of a crystal (or grain of a polycrystalline body). Perfect Real Crystals.-The term "perfect real crystals" is generally used to describe crystals with minute structural or thermodynamical inhomogeneities. The former

Jan 1, 1945

By Kendall E. Born

Production of crude oil in Tennessee during 1941 was slightly more than 15,000 bbl., about the same as in the preceding year. Two thirds of the total was from the Mississippi limestone pools in Scott and Morgan Counties. About a dozen small scattered wells in Clay, Pickett, and Fentress Counties, pumped irregularly, produced approximately 5000 bbl. Natural gas was marketed from wells in Morgan and Fentress Counties for consumption in the Sunbright and Jamestown areas, respectively. The production by counties is shown in Table I. Drilling activities in the state fell to the lowest stage since 1933. Twenty-seven wells were spudded in during 1941, of which six were drilling or only temporarily suspended on Dec. 37, 1941. Of the 22 completions, four were gas wells of undetermined quantity, but are classed as commercial, and 17 were dry or near-dry holes. One well encountered oil, but it has not been tested. The total footage drilled during the year was 29,916 ft.; the average depth of wells was 1359 ft. The more important wildcats are listed in Table 2; the distribution of tests according to physiographic divisions is given in Table 3. East Tennessee.—One well was drilled to 3480 ft. in northwestern Anderson County, in the highly disturbed Appalachian area, a region long considered the most unfavorable in the state for the accumulation of oil and gas. Another test is now drilling below 2000 ft. in this general area. Cumberland Plateau.—There were two completions in the Cumberland Plateau area. One test, drilled in northwestern Scott County in an area of former Mississippi limestone production,' encountered a considerable amount of free oil at 850 ft., about the same horizon as in the old abandoned wells. No pumping tests have been made to date. A well at Oneida, Scott County, found gas at 1579 ft. in a sandy limestone of lower Mississippian age. The volume was reported doubled by a shot, although no open-flow measurement is available. Eastern Highland Rim.—Six completions on the eastern Highland Rim resulted in two small gas wells in Fentress County, which will be used to augment the supply for Jamestown. The producing horizons are shaly limestones of Ordovician (Trenton) age. Two wells in this area tested the upper part of the Knox dolomite group, one of which encountered some free oil in a sandy dolomite at 1670 to 1681 ft. A test high on a well-defined structure in Clay County found a considerable amount

Jan 1, 1942

By Kendall E. Born

Production of crude oil in Tennessee during 1941 was slightly more than 15,000 bbl., about the same as in the preceding year. Two thirds of the total was from the Mississippi limestone pools in Scott and Morgan Counties. About a dozen small scattered wells in Clay, Pickett, and Fentress Counties, pumped irregularly, produced approximately 5000 bbl. Natural gas was marketed from wells in Morgan and Fentress Counties for consumption in the Sunbright and Jamestown areas, respectively. The production by counties is shown in Table I. Drilling activities in the state fell to the lowest stage since 1933. Twenty-seven wells were spudded in during 1941, of which six were drilling or only temporarily suspended on Dec. 37, 1941. Of the 22 completions, four were gas wells of undetermined quantity, but are classed as commercial, and 17 were dry or near-dry holes. One well encountered oil, but it has not been tested. The total footage drilled during the year was 29,916 ft.; the average depth of wells was 1359 ft. The more important wildcats are listed in Table 2; the distribution of tests according to physiographic divisions is given in Table 3. East Tennessee.—One well was drilled to 3480 ft. in northwestern Anderson County, in the highly disturbed Appalachian area, a region long considered the most unfavorable in the state for the accumulation of oil and gas. Another test is now drilling below 2000 ft. in this general area. Cumberland Plateau.—There were two completions in the Cumberland Plateau area. One test, drilled in northwestern Scott County in an area of former Mississippi limestone production,' encountered a considerable amount of free oil at 850 ft., about the same horizon as in the old abandoned wells. No pumping tests have been made to date. A well at Oneida, Scott County, found gas at 1579 ft. in a sandy limestone of lower Mississippian age. The volume was reported doubled by a shot, although no open-flow measurement is available. Eastern Highland Rim.—Six completions on the eastern Highland Rim resulted in two small gas wells in Fentress County, which will be used to augment the supply for Jamestown. The producing horizons are shaly limestones of Ordovician (Trenton) age. Two wells in this area tested the upper part of the Knox dolomite group, one of which encountered some free oil in a sandy dolomite at 1670 to 1681 ft. A test high on a well-defined structure in Clay County found a considerable amount

Jan 1, 1942

By E. D. Hummer, J. A. Younkins. J. P. Proctor

Comparatively little has been published relating practical experience with the control of the solid content of washery water systems that must be "closed." A "closed" system is one that for some reason may not be cleaned by the emission Of any effluent Of high ''lid 'content to be rep1aced by 'lean water in Order to hold the solid content of the waste water within reasonable bounds for efficient washing. It is the Purpose of this Paper to describe practical experience with such a water system and to present data that it is hoped may be of some use to those who are faced with a similar problem. The washery clarification system described comprises three thickeners and three filters, and although it is admitted that each of the fields of water settling and thickening and filtration offers a wide scope for investigation, the authors are not attempting to present the answers to these problems but to set down the results of some experience along these lines, making no claims as to the ultimate solution of the problems in hand. The subject of water clarification has vast ramifications; for example, the science of flocculation as applied to water settlillg and filtering opens up fields of wide possibilities of which as yet little is known. A comparatively recent entry into the field of water treatment, which may offer possibilities of practical application, is the use of "wetting" agents such as "Aerosol." General Arrangement of Water System So that the reader may obtain a comprehensive picture of the factors concerned in the control of a closed water system, it is necessary to give a brief description of the washing plant that is serviced by the water system to be described in the following pages. As we are not primarily concerned with the washing plant in detail, only a brief description of the flow of coal as it relates to the water system will be given here. For a more detailed account of this type of washer, the reader is referred to earlier papers,1,2 The washer, which handles o to 4-in, raw coal (750 tons per hour) is an American Rheolaveur plant of two complements; the coarse coal or sealed discharge plant and the fine coal or free discharge plant. The sealed discharge plant (Fig. I) consists of twin 48.in. primary launders, each having two washing boxes, supplemented by one 32-in. rewash launder, which also has two washing boxes. "Push" water for washing and conveying coal in these launders is supplied from a constant-head tank under pressure head of 10½ ft. at the point of introduction at the feed end of the launder. This tank also supplies water for upward or vertical currents used in the Rheolaveur or washing boxes. Each box discharges into a sealed boot elevator (Fig. I).

Jan 1, 1942

By J. A. Younkins. J. P. Proctor, E. D. Hummer

Comparatively little has been published relating practical experience with the control of the solid content of washery water systems that must be "closed." A "closed" system is one that for some reason may not be cleaned by the emission Of any effluent Of high ''lid 'content to be rep1aced by 'lean water in Order to hold the solid content of the waste water within reasonable bounds for efficient washing. It is the Purpose of this Paper to describe practical experience with such a water system and to present data that it is hoped may be of some use to those who are faced with a similar problem. The washery clarification system described comprises three thickeners and three filters, and although it is admitted that each of the fields of water settling and thickening and filtration offers a wide scope for investigation, the authors are not attempting to present the answers to these problems but to set down the results of some experience along these lines, making no claims as to the ultimate solution of the problems in hand. The subject of water clarification has vast ramifications; for example, the science of flocculation as applied to water settlillg and filtering opens up fields of wide possibilities of which as yet little is known. A comparatively recent entry into the field of water treatment, which may offer possibilities of practical application, is the use of "wetting" agents such as "Aerosol." General Arrangement of Water System So that the reader may obtain a comprehensive picture of the factors concerned in the control of a closed water system, it is necessary to give a brief description of the washing plant that is serviced by the water system to be described in the following pages. As we are not primarily concerned with the washing plant in detail, only a brief description of the flow of coal as it relates to the water system will be given here. For a more detailed account of this type of washer, the reader is referred to earlier papers,1,2 The washer, which handles o to 4-in, raw coal (750 tons per hour) is an American Rheolaveur plant of two complements; the coarse coal or sealed discharge plant and the fine coal or free discharge plant. The sealed discharge plant (Fig. I) consists of twin 48.in. primary launders, each having two washing boxes, supplemented by one 32-in. rewash launder, which also has two washing boxes. "Push" water for washing and conveying coal in these launders is supplied from a constant-head tank under pressure head of 10½ ft. at the point of introduction at the feed end of the launder. This tank also supplies water for upward or vertical currents used in the Rheolaveur or washing boxes. Each box discharges into a sealed boot elevator (Fig. I).

Jan 1, 1942

By W. M. Lehrer

RECENT development of high-temperature brazing alloys has required information regarding the eutec-tic temperature and composition of the Pd-rich section of the Pd-B system.. Literature on this subject was found to be scanty with no complete system yet determined. Buddery and welch1 report an inter-metallic compound occurring in the Pd-B system at 6.33 wt pct B (PdsBz). Another source, Sieverts and Bruning,2 indicates that after annealing at 700°C, a 1.6 and a 2.0 wt pct B alloy were two phase whereas a 0.75 pct B alloy was single phase. Recent work3 using a hot-stage microscope has proposed a eutectic temperature of 743OC. This method utilized the observation of the onset of incipient melting at grain boundaries. The eutectic composition, however, was not determined. METHODS AND PR0CEDURES Five alloys were prepared by triple inert arc-melting high-purity palladium (95.98 pct) with additions of 2 to 6 pct purified amorphous boron. The alloys were crushed within a hardened steel mortar with a steel pestle. The 2 pct alloy, however, was too tough to be crushed in the above manner so was crushed by successive reductions through a rolling mill. Approximately 17 to 18 g of the crushed alloy was used in the thermal analysis. The alloys were melted in pure quartz crucibles. The thermocouple protection tubes were also of quartz and fused along the inside wall of crucibles to prevent floating of the thermocouple. This was an expediency as centering of the thermocouple in the melt would have been preferable. Melting was done in a tube furnace with a slow flow of tank helium maintained as a protective atmosphere. Heating and cooling rates were maintained at 3.5OC per min through the critical temperature ranges by means of a synchronous motor hook-up to a furnace controller. All specimens were heated to 100°C over the indicated liquidus on heating prior to reversing to the cooling cycle. Specimens emerged from the furnace with mirrorlike brightness attesting to the protective quality of the helium atmosphere. Thermal arrests were detected by the differential thermocouple technique using chrome l-alumel couples and nickel as the reference specimen. Arrests were recorded on a Leeds-Northrup automatic X-Y recorder. The specimen temperature and temperature difference were read to + 7.5OC and ± 1.5OC, respectively. These readings were well within the sensitivity of the instrument amplifier. Chromel-alumel couples were used in lieu of Pt-Rh as very few arrests were contemplated in excess of 1200" to 1300°C, the approach of instability. No standardization was performed on these thermocouples subsequent to their use. RESULTS The thermal arrest temperatures obtained are plotted in Fig. 1 as a function of wt pct B. The composition function was obtained by chemical analysis of portions of the specimens after the thermal analysis was completed. The 2 to 6 pct nominal alloys were found to have 1.80, 2.35, 3.65, 4.18 and 5.90

Jan 1, 1960

By Charles Reed

WITH the increasing importance of clay in drilling operations which demand more precise and exacting control over its behavior, there has come the realization that most of our present methods of control over many of its important properties still represent more of an art than a science. Such a situation with respect to a material of such industrial significance is unfortunate, and naturally many investigations have been conducted to improve our knowledge. In general, these investigations have revealed the complex nature of clay behavior and while sometimes they may not have seemed to contribute directly to a solution of the field operator's problems they have been of inestimable importance in bringing to light the broad fundamental scientific principles upon which must be based any effective working theory correlating the known facts of clay behavior and predicting profitable new lines of attack for its improvement.

Jan 1, 1938

By Clemens Catesby Jones

One of the achievements of the present century has been the development of brick-making from the crude and humble handicraft of the individual to a potential industry employing machinery, requiring immense capital, and now demanding that scientific direction which will finally raise it to the importance and dignity of a modern industrial process. It is as yet in the first stages of progress in this direction. The constant obstacle to a fully developed process has been the treat-

Jan 1, 1901

By Eugene Coste

ALTHOUGH some of the observers who first paid especial attention to the occurrences of oil and gas in the strata (such as Hunt in 1859, Andrews in 1861, Winchell in 1865, Mendelejeff in 1876, Höfer in 1876, Minshall in 1881, and I. C. White in 1883) seem to have been impressed with the fact that oil and gas deposits were connected with the disturbances in the rocks caused by their upheaval,1 yet, with the exception of Mendelejeff, and possibly Andrews, these observers do not appear to have understood what is really the one essential factor in the occurrence of oil and gas in the strata: viz., the faulting, uplifting, fracturing, fissuring, and jointing always accompanying even slight rock disturbances, and in certain districts (petroliferous provinces)2 allowing solfataric hydrocarbon emanations to force their way up from the interior and to reach and impregnate the porous portions of sediments subjected to the disturbances. Instead of this simple explanation to account for the observed connection between petroleum deposits and rock disturbances, most of the observers mentioned above, and many others who have followed them on the name lines since, have entirely reversed the problem. To them, instead of the dissemination of gases from fissures into the sediments, it presented the accumulation and concentration, according to anticlinal or other geologic structures, of oil and gas originally present throughout the whole mass of the strata where they were produced by the decomposition or distillation of organic remains. Whether this important problem involves accumulation from sources within the oil-bearing strata themselves, or infiltration and dissemination from outside sources, may be easily determined if all preconceived ideas are put aside and the established facts only are considered.

Jan 9, 1914

By A. M. Gaudin, R. T. Hukki

PREVIOUS work on the principles of comminution has shown: (I) that the surface produced is proportional to work input (Rittinger law, 1a-3); (2) that there is regularity to the weight distribution of the fragments according to size.4-10 In this paper it is brought out that the surface on the fragments is distributed in definite and simple relation to size. The experimental work has involved: I. Construction of an apparatus capable of measuring the surface of mineral fragments independently of the chemical composition of the fragments and independently of the site of the surface; 2. Refining the methods available for measurement of particle size; 3. Designing and building a crusher capable of operating on very small quantities of mineral, if necessary on single crystals, and in such fashion as to minimize handling losses of material. Complete experiments have been carried out with massive quartz and individual quartz crystals. Partial experiments, lacking surface measurements, have been made with glass spheres, galena, sphalerite, fluorite, salt and coal.

Jan 1, 1944

By B. Woyski

Many writers, in discussing defects caused by oxidation and gassing of bronzes and red brasses advocate substantially the same cure for both. But from its nature, oxidation cannot take place if there is an excess of fuel in the furnace, while the gases absorbed by some alloys are products of incomplete combustion of the fuel. Hence the metal can be either oxidized or gassed, but it is doubtful whether these actions can take place simultaneously. Oxidation can be easily overcome by the use of deosidizers or it may be avoided by protecting the molten metal with suitable fluxes. Absorption of gascs is more difficult to overcome: the regulation of the air and fuel, so as to produce complete combustion, and the protection of the bath by mineral fluxes arc the most important factors. Gas expulsion, resulting in gas holes, porosity, unsoundness, and swollen or cauliflower-headed risers, is said to have several causes. One writer1 lists the most common causes in the order of their importance, as follows: Superheated metal, dirty or slaggy furnace conditions, using metals low in quality or those previously subjected to bad melting practice, poor grade of fuel, use of newly lined or damp ladles, indiscriminate mixing of scrap or illogical combinations of metal. Superheating the metal usually occurs when the heat is ready to be poured but for some reason must be held in the furnace. In this case, a careful furnace tender tries to avoid overheating the metal by keeping a mild fire; that is, a reducing fire which, unfortunately, results in gassing the metal. A dirty, slaggy furnace may result in gassing the metal by retarding the heating and prolonging the time necessary to bring the metal to the proper temperature, thereby increasing the chances of gassing in uncertain furnace atmosphere. It is doubtful whether rnetals of low quality have anything to do with gassing molten metal, except, possibly in the case of metals containing

Jan 1, 1923

By B. Woyski

Many writers, in discussing defects caused by oxidation and gassing of bronzes and red brasses advocate substantially the same cure for both. But from its nature, oxidation cannot take place if there is an excess of fuel in the furnace, while the gases absorbed by some alloys are products of incomplete combustion of the fuel. Hence the metal can be either oxidized or gassed, but it is doubtful whether these actions can take place simultaneously. Oxidation can be easily overcome by the use of deosidizers or it may be avoided by protecting the molten metal with suitable fluxes. Absorption of gascs is more difficult to overcome: the regulation of the air and fuel, so as to produce complete combustion, and the protection of the bath by mineral fluxes arc the most important factors. Gas expulsion, resulting in gas holes, porosity, unsoundness, and swollen or cauliflower-headed risers, is said to have several causes. One writer1 lists the most common causes in the order of their importance, as follows: Superheated metal, dirty or slaggy furnace conditions, using metals low in quality or those previously subjected to bad melting practice, poor grade of fuel, use of newly lined or damp ladles, indiscriminate mixing of scrap or illogical combinations of metal. Superheating the metal usually occurs when the heat is ready to be poured but for some reason must be held in the furnace. In this case, a careful furnace tender tries to avoid overheating the metal by keeping a mild fire; that is, a reducing fire which, unfortunately, results in gassing the metal. A dirty, slaggy furnace may result in gassing the metal by retarding the heating and prolonging the time necessary to bring the metal to the proper temperature, thereby increasing the chances of gassing in uncertain furnace atmosphere. It is doubtful whether rnetals of low quality have anything to do with gassing molten metal, except, possibly in the case of metals containing

Jan 1, 1923

By F. W. Gordon

The Whitwell firebrick hot-blast stove, for furnace use, may be seen in its three main stages of development in the accompnying drawings. Fig. 1 is the stove of 1869, the year in which it was thoroughly tested at the Consett furnaces, England; Fig. 2, the stove of 1876 and 1877, in which it was intended to reduce the cost by increasing the height; Fig. 3, the stove of 1880. Many modifications were made from time to time, generally in the direction of improvement, but the drawings illustrake the main features of progress. In the stove of 1869 the plan was to introduce the gas at A, and pass it up and down between each alternate wall, the air in the reverse direction, passing in at B. The friction in this stove was so great, owing to the restricted area of the passages and the many revervals of the gaseous current, that it was deemed imprudent to build the stoves higher than 28' 6". Another reason mas that the great importance of cleaning was carefully kept in view, and it was very difficult to operate any hand scraper even to this depth. For these reasons the 22' X 28½' stove held the field for several yearn. A slight change made from this was to the 18' X 40' stove, where the height was increased, but the dumber of walls diminished. In this stove the friction was somewhat reduced, but so was the heating surface, and although it cost a little lea it was not any better. The next important change, seen in Fig. 2, was by increasing the height to GO feet and keeping the full number of walls in the stove. The heating surface and mass were much increased in proportion to the cost, and the friction decremed by alterllating over and under two or more walls, instead of one, as formerly. This stove gave admirable satisfactiou, but, although the proper doors were provided, it was very difticult to clean, owing to the long (distance the scrapers lid to traverse. Stove No. 3 is a modification of No. 2. The great question was how to decrease the cost mithotlt impairing in any yaw the

Jan 1, 1881

By F. W. Gordon

THE Whitwell firebrick hot-blast stove, for furnace use, may be seen in its three, main stages of development in the accompanying drawings. Fig. 1 is the stove of 1869, the, year in which it was thoroughly tested at the Consett furnaces, England; Fig. 2, the stove of 1876 and 1877, in which it was intended to reduce the-cost by increasing the height; Fig. 3, the stove of 1880. Many modifications were made from time to time, generally in the direction of improvement, but the drawings illustrate the main features of progress. In the stove of 1869 the plan was to introduce the gas at A, and pass it up and down. between each alternate wall, the air in the reverse direction, passing in at B. The friction in this stove was so great, owing to the. restricted area of the passages and the many reversals of the gaseous current, that it was deemed imprudent to build the stoves higher than 28' 6'". Another reason was that the great importance of cleaning was carefully kept in view, and it was very difficult to operate any hand scraper even to this depth. For these reasons the 22' X 28 1/2' stove held the field for several years. A slight change made from this was to the 18' X 40' stove, where the height was increased, but the number of walls diminished. In this stove the friction was somewhat reduced, but so was the heating surface, and although it cost a little less it was not any better. The next important change, seen in Fig. 2, was by increasing the height to 60 feet and keeping the full number of walls in the stove. The heating surface and mass were much increased in proportion to the cost, and the friction decreased by alternating over and under two or more walls, instead of one, as formerly. This stove gave admirable satisfaction, but; although the proper doors were provided, it was very difficult to clean, owing to the long distance the scrapers had to traverse. Stove No. 3 is a modification of No. 2. The great question was how to decrease the cost without impairing in any yaw the

Jan 1, 1881