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By Leon H. Nelson

Several factors which affect the segregation and solidification of killed hot-topped steel ingots are: (1) pouring temperature, (2) volume in the hot top, (3) taper in the ingot, (4) pouring rate by varying the nozzle size, (5) segregation of several elements, (6) moving ingots before completely solidified. In most of this discussion, segregation will be measured in terms of carbon variation only. All the data given are results on S.A.E. 1040 analysis of fully killed steel direct-poured in hot-topped molds giving 20-in, square ingots. Thus the variables of analysis and ingot size and contour are eliminated. Segregation results are all on the rolled-bloom size, not on the ingot itself. They are results from plant-control work and not results of special research on ingot segregation. Pouring Temperature The temperature (or, more correctly, the amount of superheat above the liquidus-solidus) of the steel entering the ingot is, of course, one of the most important factors influencing segregation and solidification. Table 1 gives the average segregation of a number of heats of S.A.E. 1040 steel with normal pouring temperatures of 2775" to 2825" F. The table also gives some data on segregation in hot heats (pouring temperature 2840" to 2870" F.) and in cold heats with some skull (poured at 2725" to 2760" F.). The results in Table 1 are on steel ingots with 20-in. square cross section and 60 in. long to the hot top. The ingot weighs 7100 lb. and the hot top contains 14.3 per cent of the total ingot volume and 11.2 per cent of the total ingot weight. The results are from drillings after rolling the ingots to bloom size. Segregation results obtained on the bloom are probably not as great as they would be in the ingot itself, since heating the ingots for rolling can perhaps cause some migration of carbon from regions of high and low carbon to those of average carbon content.

Jan 1, 1937

By J. M. Donkers, R. de Groot

The various objectives of dredging at sea require different methods and radically different equipment for their optimum fulfillment. In the majority of cases, sea dredging is done by means of dredging equipment connected to a pontoon or ship floating at the surface. As the supporting hull is subject to the influence of waves, swells, currents and wind, the connecting point of the dredging equipment to the hull will generally move relative to the sea bottom with 6° of freedom. The more important hull motions are surge, heave, pitch and roll. Depending on the actual sea and weather conditions and the size of the hull, some of these motions can be so large that dredging equipment of rigid construction (normal or inland dredges) cannot be used. In those cases where mechanical disintegration of the bottom is necessary and where accurate dredging is required, the designer must find a solution for this problem. For cases where the bottom consists of soils that can be handled by plain suction, highly sophisticated dredging equipment such as the trailing suction hopper dredge permit dredging under all but the most severe sea state conditions. This type of dredge picks up the soil from the sea bottom while slowly underway. The drag suction head is fitted on a suction pipe of such flexibility that the supporting ship can carry out all six movements in relation to the draghead (heave, pitch, roll, sway, yaw and surge), while the draghead remains in firm contact with the bottom. The suction pipe is fitted with flexible hoses, a universal hinge, a horizontal hinge, axial turning gland and sliding turning gland with horizontal axis and is suspended flexibly from the ship incorporating swell compensating buffer gear, keeping the wires taut and the draghead bottom contact pressure fairly constant while the dredge moves up and down. Due to the fact that the draghead has a low bottom contact pressure and has little tendency to sink into the bottom, this compensation is not difficult to realize.

Jan 4, 1974

THE primary interest in the subject of this chapter lies in the fact that various heats of steel made to the same chemical specification do not always-have the same properties. The properties considered here, of course, are those inherent in the ingot immediately after solidification and not qualities imparted by variations in subsequent mechanical or thermal treatment. The expression "made to the same chemical specification" is used because some of the variations in properties are due to variations in chemical analysis within the specified ranges of those elements commonly specified and determined. Other variations in properties are due to variations in those constituents of steel (elements or compounds) that are not ordinarily included among the elements specified, thus not a part of the specified "composition." The term "constitution" is used to include not only the specified composition but also the nature and distribution of every element or compound contained in the steel entering the ingot mold; also included are items such as aluminum oxides and nitrides, presence of soluble gases, and dispersion of nonmetallic particles. When it is considered that the constitution of steel is determined by the addition or absorption into the bath of all such constituents from whatever source, it follows that constitution is of necessity the final result of steelmaking practice. It is the agency through which steelmaking practice operates to control the properties of the steel. The term steelmaking practice is here used in the broad sense, meaning the control of all the materials entering the steel and of the conditions under which the process is carried out. Steelmaking practice, thus defined, establishes the chemical system within which the reactions between components must proceed in obedience to the laws of chemistry. Thus the chemical constitution of the steel is established and, through constitution, the properties of the metal are established. In the preceding chapters it has been shown how the constitu-

Jan 1, 1951

I. N. KNAPP, Ardmore, Pa. (written discussion*).-The possibility of storing natural gas in the sands f exhausted gas pools might be, in many cases, a, good engineering proposition, but it cannot be considered a practical business proposition tinder the usual competitive leasing and operating conditions that exist in the natural-gas business. Under the usual conditions of diversified land ownership and leasing with all lack of cooperation, various operators drill into the same pool or reservoir and drain out the gas under each other's land. To attempt to use for storage purposes the depleted sands f any one pool having such various competing ownerships would be highly impractical, considered from operating and business standpoints, unless there was cooperation with the interests owning adjacent wells and leases or the purchase f the same. Also, it would be very difficult to find out whether all old or abandoned wells in any pool had been properly, plugged and thus prevent the waste of gas brought from a distance for storage. Another objection to Mr. Panyity's proposition is the probability that no lease made in the past contemplated the use of a gas sand for storage purposes. Very likely, then, the operator would have a lawsuit on his hands for the unlawful use of a lease if he attempted the storage f such gas without first obtaining additional lease rights. In some instances salt water could not be pumped from a gas well in the customary way of pumping oil wells on account of the deposition of salt in the pump valves or in the working barrel or tubing. Very ingenious compressed air jets have been devised and arranged with suitable piping to blow out such salt-water accumulations. In many pools it would be impracticable to drill a water pocket below a gas sand, as suggested, since such deeper drilling would probably. intensify water troubles.

Jan 5, 1919

By Wilbert McBride

Two Alco 3 ½ -ton motor trucks were used by Young Bros. while operating at the Mammoth Collins mine at Shultz, Ariz. One was equipped with an oil tank holding 1,075 gal. and was used for the transportation of "tops." The, other was fitted with a stake body and used to carry machinery, wood, rails, pipe and all classes of miscellaneous supplies. The bodies were made of oak with maple flooring and were attached to the frame of the chassis by U-bolts, to avoid drilling the main members of the frame. Most of the hauling was done from Tucson, a distance of 47;2 miles. During the first. 3 months, part of the road was in very bad condition and the tire cost was excessive. After this part was repaired the road was in fair condition, but never good. There were no excessive grades or bad sand, but wagon ruts, too narrow for the truck wheels and of a different gage, caused heavy tire loss; while chuck holes, sharp curves and stones, both imbedded and loose, were objectionable features. During wet weather the trucks could not get sufficient traction to climb some of the hills and were likely to stick in the mud in certain places, so that no attempt was made to run them unless they were on the road when the rain started. This lost time amounted to about 5 per cent. of the total, but, whenever possible, it was utilized in making minor repairs. The price of gasoline, was from 17 to 21 c. per gal. Rubber tires were used throughout. Drivers were paid $4.50 to $5 per shift, and a return trip to Tucson was counted as two shifts even when made in one day. Drivers were provided with a room in Tucson and were paid for all time lost due to causes beyond their control. Trucks were loaded one way only.

Jan 7, 1916

0PINION was general that this year's meeting of the Institute of Metals Division was one of the best in its history. In addition to its full and exceptionally fine program of professional papers, there were several other features of general interest-an in-spiring annual lecture by Dr. Cecil H. Desch which appears in abstract elsewhere in this issue, Mr. Sing-master's talk on the zinc industry at the annual dinner, and the presentation of the James Douglas Medal to one of the members of the Division, Dr. Zay Jeffries. Four technical sessions of the Division were held, dealing respectively with zinc, copper, aluminum, and general metallography, and in addition there was a joint session with the Non-ferrous Metallurgical Committee of the Institute. All of the papers presented were at-tended with much interest and followed by considerable discussion. The papers on plastic deformation of zinc by Messrs. Mathewson and Phillips, Romig, and Hoyt were of particular interest and awakened an extended discus-sion. They well illustrated the progress which is being -made today in the understanding of the mechanism of flow of metals, and the ingenuity of the authors in their crystallographic method of attack of this difficult problem was quite generally admired. A very old subject was treated in a modern way by Messrs. Corson and Bain in two papers on the harden-ing of copper and copper alloys. There has always existed a myth that the ancient Egyptians were masters of an art not possessed by ourselves; viz., that of hard-ening copper. This myth must have been quite defi-nitely dispelled in the minds of all those who listened to this admirable paper. Mr. Corson has applied the modern art of precipitation hardening to this old prob-lem with substantial success, employing small amounts of chromium, nickel, silicon, and cobalt for this purpose. The commercial application of these very important .developments of Mr. Corson is being actively investi-gated at the present time.

Jan 3, 1927

By Harry Tufft

FOR many years the treatment of mine timbers with preservatives was confined to a few pioneer plants in the United States, and it is only in the past few years that the practice has grown appreciably. In a field study of the mine timber situation in Illinois, Pennsylvania, and further study of the situation in the country as a whole, I found that most mine operators did not keep records on mine timber that would afford the necessary data for determining the possible savings from preservative treatment. Some primary questions the mining engineer should be able to answer before making his decision on preservative treatment. for a particular mine are: (1) Quantity and cost of timber going into permanent workings annually; (2) quantity and cost of annual replacements due to decay; (3) life of untreated timber in different places; (4) desired life of timber. With the necessary facts in hand, he can then con-fidently select a method of treatment and preservative that is best suited to his needs. In former years when timber was cheap and an abundant supply could be had close at hand, as was the case in the majority of mining regions, the mine op-erator did not concern himself much except to see that enough was supplied to keep the workings safe. The cost figure for timber and labor, distributed to cost per ton of ore, was all the bookkeeping necessary. With present costs of timber, labor, and increasing length of haul to the mine, many operators are paying closer attention to timbering costs and studying them in. more detail. Some of the larger and more progressive opera-tions now keep detailed' figures that give information on all phases of their timber problems. However, at the majority of mines the data available do not permit such analysis. Checks as to where the different con-signments are placed, the date of setting, and the period

Jan 6, 1927

By John C. McDonald

The amount of published literature in the field of mechanical properties of magnesium alloys is not great; particularly with respect to rolled alloys. Haughton and Prytherchl have summarized most of the articles to 1937, including their own work on sheet. Although many papers can be found dealing with the technology of magnesium and the alloys now in commercial use, there does not seem to be any work dealing exclusively with the variation in properties of rolled alloys as caused by changes in alloy composition. Comparison of published data reveals considerable discrepancies in properties of alloys of the same composition, probably due to differences in the details of working and heat-treating followed by different workers. The purpose of this paper is to study the properties of alloys in conditions where the effects of such differences have been eliminated. It is well known that the strength and ductility of metals are functions of the working and heat-treating they have received, as well as of their chemical composition. In comparing alloys with respect to these properties, therefore, all possible combinations of the variables of the fabrication procedure ought to be carried out on each alloy. One or more of these treatments mill produce the highest ductility, or strength, or both. These highest properties would then be selected as characteristic of each alloy, and alloys would be compared on the basis of those properties. Thus a separation of the effect of composition and that of workiiig and heat-treating would be achieved. In this paper, however, a compromise with completeness has been made by carrying out a restricted number of treatments. As a consequence, the properties obtained are not necessarily the best that the alloy is capable of exhibiting; but since all alloy3 have been treated by the same method, the results ought to be comparable. The elements selected for the study comprise a class that will alloy easily with magnesium, and that are reblatively cheap. Each was added in different amounts, up to a limit that varied with the element.

Jan 1, 1940

By R. W. Young, Arthur F. Taggart

The tests herein described are part of an extended series of expel<ments, performed by the authors together with J. F. McClelland and L. W. Bahney, on the reclamation of metallics from foundry and manufacturing-plant scrap. The most obstinate problem encountered was the proper cleaning of the metal. Introduction In the manufacture of brass and brass products the weight of the finished product leaving the plant is much less than the total weight of. copper and zinc entering. A small part of this discrepancy is due to the unavoidable oxidation of the metals in melting, but by far the largest part of the loss is in the form of metallic particles of copper,. zinc, and brass. These losses occur principally at three points in the process: (a) in the casting-shop ashes; (b) in the slags from furnaces melting scrap brass; (c) in material spilled on the floor throughout the manufacturing process. The amount of these products in some plants is nearly 100 tons per 24 hours. Casting-shop ashes contain the metal spilled from the crucibles during melting and pouring, and the metal included in the slags formed in the melting process. The ashes also contain pieces of broken crucibles with adhering metal; 20 to 30 per cent. of unburned coal is also present. The metal in casting-shop ashes contains clean pieces of zinc or copper ingots weighing 1 to 2 lb., jagged pieces of metal of all shapes ranging in size from several inches down to the finest dust, and shot and botryoidal shapes ranging in size from 2 or 3 in. down to 0.01 mm. or less in diameter. Slags from furnaces melting scrap brass contain metal in the form of small shot. Floor sweepings occur in all shapes: spirals, thin shavings, pins and pin-like pieces, wire, rods, and buffing-wheel dust are the commonest.

Jan 1, 1916

By Bezalel C. Haimson

Anna, Ohio, at the junction of Cincinnati, Findlay and Kankakee arches, has been the site of repeated and sometimes damaging earthquakes. As part of a seismicity investigation near-surface (0.15-1 m depth) overcoring strain measurements were conducted in four limestone and dolomite quarries surrounding Anna, the results of which suggest a complicated regional stress pattern, with changes in the maximum horizontal stress direction from N45ºE to N15ºW. Since such abrupt stress fluctuations are rather atypical in the Midwest and since the reliability of near-surface tests in defining regional stress had not been established, we decided to remeasure the stresses at the same locations but at greater depths (0-200 m) using the hydrofracturing method. Owing to the weak horizontal bedding planes of the Silurian shaly limestones and shaly dolomites and the relatively shallow depths, many of the tests yielded horizontal fractures, providing information only on the vertical principal stress (-0.029 MPa/m depth). However, sufficient tests in each of three testholes resulted in vertical hydrofractures to enable the calculation of all three principal stresses. Within 50-170 m depth the horizontal stresses in all three quarries appear to belong to a uniform regional Stress field defined by the following relations: [&apos;]Hmin = 5.1 + 0.014 D; [0] Hmax = 10.1 + 0.014 D, where D is depth in meters. The direction of [O]Hmax within 50-170 m depth is uniform at N70°E (±15º). The hydro- fracturing results obtained at Anna, Ohio are in agreement with the prevailing stress regime in the midcontinent both with respect to magnitudes and directions. The results suggest a possible thrust mechanism for a proposed NW-SE fault along which most of the earthquake epicenters have been located, and a left lateral strike-slip at greater depths. The focal mechanism solution of a recent major earthquake near Sharpsburg, Kentucky, some 200 km south of Anna, also indicates strike-

Jan 1, 1982

By W. J. Sharwood

IN the cyanide process, gold and silver are dissolved from crushed ore as double alkali-metal cyanides, from which they may he precipitated by such positive metals as sodium (amalgam), aluminum, or zinc, or by electrolysis. Two extreme conditions may he noted. Some works, especially slime plants practising decantation, use a relatively large volume of solution-possibly 4 or 5 tons per ton of ore-nearly all of which may require precipitation, so that the solutions handled are of much lower value per ton than the ore. On the other hand, in some leaching plants it is possible to extract with very little solution, and to percolate some of this more than once through the charge before precipitation, so that the solution to be precipitated may he much less than half the weight of ore, and proportionally richer. Solution intended for further use need not have all its precious metal removed, but any that has to be thrown away should be impoverished as far as is economically possible. In spite of certain advantages possessed by other precipitants, zinc in some form has been almost universally used. In some of the first attempts to utilize cyanides as gold solvents, a "piece or plate of zinc" was suggested as a precipitant, but extension of surface was early recognized as a desideratum. Macarthur and the Forrests adopted a "metallurgical filter" of zinc shaving, turned from disks or rolled sheets. They had previously experimented on other forms of zinc, and Macarthur records having tried zinc dust, which had of course been long known as a general reducing agent. It had also been known and used as a precipitant of precious metal from plating and photographic solutions, and comminuted zinc had been patented for recovering copper, etc., from ore leaches. Other inventors proposed the virtual making of zinc powder by the attrition of balls of zinc, and by similar means, during the passage of a stream of gold-bearing solution.

Jan 9, 1917

By John C. McDonald

The amount of published literature in the field of mechanical properties of magnesium alloys is not great; particularly with respect to rolled alloys. Haughton and Prytherchl have summarized most of the articles to 1937, including their own work on sheet. Although many papers can be found dealing with the technology of magnesium and the alloys now in commercial use, there does not seem to be any work dealing exclusively with the variation in properties of rolled alloys as caused by changes in alloy composition. Comparison of published data reveals considerable discrepancies in properties of alloys of the same composition, probably due to differences in the details of working and heat-treating followed by different workers. The purpose of this paper is to study the properties of alloys in conditions where the effects of such differences have been eliminated. It is well known that the strength and ductility of metals are functions of the working and heat-treating they have received, as well as of their chemical composition. In comparing alloys with respect to these properties, therefore, all possible combinations of the variables of the fabrication procedure ought to be carried out on each alloy. One or more of these treatments mill produce the highest ductility, or strength, or both. These highest properties would then be selected as characteristic of each alloy, and alloys would be compared on the basis of those properties. Thus a separation of the effect of composition and that of workiiig and heat-treating would be achieved. In this paper, however, a compromise with completeness has been made by carrying out a restricted number of treatments. As a consequence, the properties obtained are not necessarily the best that the alloy is capable of exhibiting; but since all alloy3 have been treated by the same method, the results ought to be comparable. The elements selected for the study comprise a class that will alloy easily with magnesium, and that are reblatively cheap. Each was added in different amounts, up to a limit that varied with the element.

Jan 1, 1940

By Joseph P. Kittredge

At the time this matter first came up in 1912, the National Malleable and Steel Castings Co. had seven basic-bottom open-hearth furnaces in its plant at Sharon, Fa., using fuel oil, then costing about 2½¢ per gallon. The fuel was satisfactory but its cost fluctuated widely, therefore the use of pulverized coal, which had been successful in the cement industry and in some metallurgical furnaces, was suggested. After a thorough investigation, and an actual trial on one of the open-hearth furnaces, to be certain that the siliceous ash in the coal would not seriously affect the basic slags, the management of this company approved its adoption and a complete installation was started. The conclusion had been reached that the success of the operation depended on pulverizing the coal to greater fineness than had thus far been accomplished, and all equipment was chosen with this in mind. A coal drier was deemed essential, and one of ample capacity and efficiency was selected, which has done all that was expected of it, working without failure and with very small maintenance cost, and is still in operation. Pulverizers The company demanded a pulverization of at least 90 per cent through a 240-mesh screen, with consistent results, and a machine was chosen that was grinding other materials than coal to the fineness desired. The control of fineness was obtained through a vacuum separator, and was governed by the size of the separator and the number and construction of the valves necessary to expand and direct the air current. These valves can be set to obtain any degree of fineness desired, and the result is consistent. Two machines were installed, each capable of producing 2½ tons per hour, 95 per cent through 240 mesh. These machines have done everything expected of them, have run continuously, and are still in operation. An examination of some of our pulverized coal by elutriation and microscopic measurement disclosed that a 1-lb. lump of bituminous coal,

Jan 1, 1940

By P. B. Elkin, K. C. Ten Brink, Allen D. Garrison

It is the purpose of this article to present the results of an investigation of certain clay and shale suspensions having viscosities that are materially influenced by fluid motion, and to discuss the bearing of these results upon the choice of policy in the control of drilling fluids. A previous article described the design and the characteristics of an instrument adapted to measure the viscosity of plastic suspensions during continuous uniform motion and at a variety of speeds.&apos; It has long been recognized that the viscosity of a clay suspension depends on the past history of the fluid motion. Since an abundance of literature is available on this phenomenon,2 it is not necessary to describe it in more than general terms. It is usually observed that rapid motion reduces the viscosity of a clay suspension, and that some time is required for the viscosity to fall to its equilibrium value after the steady motion is started. On reducing the speed of motion to some lower value, the viscosity again rises, but it also requires some time to attain a steady viscosity value at the slower rate of motion. Thus clay suspensions are usually observed to be increasing in viscosity as time passes when the measurement has been immediately preceded by fluid motion that was more rapid than that employed in the measurement. And it is usually observed that the viscosity falls as time passes when the measurement has been preceded by more quiescent conditions. Reed,3 and Broughton and Hand4 have reported a condition of observation of clay suspensions in which the viscosity was observed to fall during the first few moments of steady motion, and rise thereafter. The characteristics of the new instrument are particularly well adapted to studies of this kind. With it we have been able to observe all of the phenomena described above, and it is important to understand their nature because they all occur at some time during normal drill-

Jan 1, 1940

By Ira B. Joralemon

The sampling of disseminated copper deposits has been describeu often but the method of combining assays to give the true shape and value of the orebody as it will be mined has received less attention. As the ore mined during five or ten years at several of the great disseminated properties has averaged materially lower in grade than the published estimates, the question of the sampling and estimating of these orebodies seems timely. In this paper, attention is given particularly to factors that may cause errors in the final estimate. Sampling of diamond-drill holes, churn-drill holes, and underground workings is briefly described in the first part of the paper; then the method of combining assays to give the average grade and tonnage that will be mined is taken up in some detail. The necessity of study of the geology of the deposit and of probable costs is emphasized. Finally, the methods of calculating tonnages are outlined. DlAMOND-DRILL SAMPLING There are three main requisites for accurate diamond-drill sampling. First, the core should be removed and the hole cleaned out at the beginning of every sampling interval, usually 5 ft. (1.5 m.). After the rods are let down, water should be run through them until it becomes clear. The water must be clear before drilling starts. &apos;In this way the material knocked down from the sides of the hole by the descending rods is washed away, instead of being left to salt the sludge sample. The second requisite is to save all the sludge and all the core from every sampling interval. Where the material is uniformly heavy, the cuttings will settle suffciently in a box, through which the sludge flows s1owly.l Where part of the material is too light to settle readily, the sludge should be run into barrels, and allowed to settle until the water becomes clear. Then the clear water is siphoned off, and the sludge evaporated to dryness over a slow fire, sacked, and assayed.2 To obtain

Jan 1, 1925

By Joseph P. Kittredge

At the time this matter first came up in 1912, the National Malleable and Steel Castings Co. had seven basic-bottom open-hearth furnaces in its plant at Sharon, Fa., using fuel oil, then costing about 2½¢ per gallon. The fuel was satisfactory but its cost fluctuated widely, therefore the use of pulverized coal, which had been successful in the cement industry and in some metallurgical furnaces, was suggested. After a thorough investigation, and an actual trial on one of the open-hearth furnaces, to be certain that the siliceous ash in the coal would not seriously affect the basic slags, the management of this company approved its adoption and a complete installation was started. The conclusion had been reached that the success of the operation depended on pulverizing the coal to greater fineness than had thus far been accomplished, and all equipment was chosen with this in mind. A coal drier was deemed essential, and one of ample capacity and efficiency was selected, which has done all that was expected of it, working without failure and with very small maintenance cost, and is still in operation. Pulverizers The company demanded a pulverization of at least 90 per cent through a 240-mesh screen, with consistent results, and a machine was chosen that was grinding other materials than coal to the fineness desired. The control of fineness was obtained through a vacuum separator, and was governed by the size of the separator and the number and construction of the valves necessary to expand and direct the air current. These valves can be set to obtain any degree of fineness desired, and the result is consistent. Two machines were installed, each capable of producing 2½ tons per hour, 95 per cent through 240 mesh. These machines have done everything expected of them, have run continuously, and are still in operation. An examination of some of our pulverized coal by elutriation and microscopic measurement disclosed that a 1-lb. lump of bituminous coal,

Jan 1, 1940

By K. C. Ten Brink, Allen D. Garrison, P. B. Elkin

It is the purpose of this article to present the results of an investigation of certain clay and shale suspensions having viscosities that are materially influenced by fluid motion, and to discuss the bearing of these results upon the choice of policy in the control of drilling fluids. A previous article described the design and the characteristics of an instrument adapted to measure the viscosity of plastic suspensions during continuous uniform motion and at a variety of speeds.&apos; It has long been recognized that the viscosity of a clay suspension depends on the past history of the fluid motion. Since an abundance of literature is available on this phenomenon,2 it is not necessary to describe it in more than general terms. It is usually observed that rapid motion reduces the viscosity of a clay suspension, and that some time is required for the viscosity to fall to its equilibrium value after the steady motion is started. On reducing the speed of motion to some lower value, the viscosity again rises, but it also requires some time to attain a steady viscosity value at the slower rate of motion. Thus clay suspensions are usually observed to be increasing in viscosity as time passes when the measurement has been immediately preceded by fluid motion that was more rapid than that employed in the measurement. And it is usually observed that the viscosity falls as time passes when the measurement has been preceded by more quiescent conditions. Reed,3 and Broughton and Hand4 have reported a condition of observation of clay suspensions in which the viscosity was observed to fall during the first few moments of steady motion, and rise thereafter. The characteristics of the new instrument are particularly well adapted to studies of this kind. With it we have been able to observe all of the phenomena described above, and it is important to understand their nature because they all occur at some time during normal drill-

Jan 1, 1940

By Dorsey Hager

DORSEY HAGER, Tulsa, Okla.-I have been asked why the Dexter region is dry. I would like to know myself. I drilled two dry wells on that same anticline which has production to, the east and west and south and north. That same anticline has seven domes that have been drilled and only three have proven productive out of the seven. In other words, you have one well-defined anticline with seven domes along its length, all mappable, all checked carefully, and only three of those seven have produced. Now why the others did not produce, I do not know. L. L. HUTCHISON, Tulsa, Okla.-There is no appreciable difference in the character or structure of the sands? DORSEY HAGER.-NO, I have never .been able to see any appreciable difference in the sands where we got production and Where we did not get it. I will say that the deepest wells we drilled, in the vicinity of Dexter, had no sands at the point where they got the production farther north. I. N. -KNAPP, Ardmore, Pa.-I first went to the Kansas-Oklahoma field in 1895 and occasionally thereafter until 1899, when I began drilling; for oil. I started close to wells that were producing gas and which, when drilling, lead made good oil showings in a sand above the gas. I thought these showings were good enough evidence of an oil pool for me without looking for any anticline and I made a paying development in what&apos; I was afterward told by geologists was probably a synclinal trough. If I remember correctly Dr. Orton&apos;s report on the lola gas pool (about 1898) he distinctly said that he found no evidence of anticlinal structure and concluded from the records of a large number of wells that there, was a terraced structure of the productive gas sands, of which there were no surface indications.

Jan 4, 1917

By G. B. Gould

THE softening temperature of coal ash, as determined in the labora-tory, has been used for years as an indication of the tendency of coal to form clinker and slag. It has not, however, provided an index of unfail-ing and complete reliability for forecasting the relative performance of different coals, even in the same plant and under the same conditions of operation. A large amount of investigation has been done in attempts to account for this, but practically all of this has been in the direction of studying the chemical constitution of coal ash. Much has been learned, but without much progress toward a better practical application of knowledge to the selection of coal. There has always seemed to be an important factor that eluded discovery. It has long been recognized that the ash-softening temperature as determined in the laboratory had one weakness, in that it represented the temperature at which a thorough mixture of the whole ash of the coal would melt, the mixing having taken place before the heat was applied. This does not, of course, simulate what takes place in practice. With certain exceptions, which will be noted later, almost all of the investiga-tions that have been made, especially the chemical studies of coal ash, have likewise dealt with a mixture of the whole ash in the coal. The present investigation differs from these fundamentally in its approach to the problem. It started from the observation that some clinkering and slagging obviously takes place in a boiler furnace at tem-peratures below the laboratory-determined ash-softening temperature of the coal. Knowing that coal as it is shipped to market is a hetero-geneous mixture of diverse mineral substances, each of which may act independently of the others in the initial stages of clinker and slag formation, it seemed logical to investigate separately the softening tem-perature of the ash in physically separable portions of the coal, and to determine the relative quantities of ash contributed by each portion.

Jan 1, 1940

By M. Van Siclen

THE outstanding fact in connection with dust disease in the United States at present is the growing recognition of its seriousness by state officials and by the more progressive operators of mining, metallurgical and allied industrial plants. The same may perhaps be said of labor in some of its better organized centers, but the average independent non-union workman continues, as of yore, to suffer the toll of disability and even of death from dust inhalation without realization of the source of his ill-being. Progress in the betterment of the handling of sufferers from dust disease and of the conditions creating dust hazards in mining and allied industries is pursuing a course similar to that of the now widespread campaign against accidents, in which the risk is more obvious, more severe, and was naturally recognized sooner. The coming on of dust disease is generally relatively slow and its immediate effects not infre-quently masked by or attributed to other diseases. Marked exceptions to this general rule have occurred in districts where the dust is particularly pernicious, such as the Rand and Joplin; yet such exceptions, unhappy in themselves, opened the eyes of medical men, and of those in other localities charged with the responsibility for the welfare of industry, to the much more widespread if less spectacular hazard existing from the inhalation of dust in all rock-excavating operations and all industrial operations creating inorganic dust, whether it be crushing and grinding, sand-blast-ing, granite-cutting, or what not. Advancement to date in the United States in prevention and treat-ment has been slow, yet the record shows that quantitative methods for determining the degree of hazard and means for decreasing it were being developed as far back as 25 years ago; and that more rapid progress may be looked for from now on. In 1908, in this country, F. L Hoffman?(1) discussed the mortality from consumption in dusty trades, especially brass foundries; and in 1913 E. R. Hayhurst(2) described the effects of inhalation

Jan 1, 1933