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Jan 1, 1881

By R. P. Smith

IN 1937 the employees of the Hollinger Consolidated Gold Mines Ltd., at Timmins, Ont., Canada, approached organized medicine for a plan to provide themselves and their families with a complete medical service including hospitalization. This approach was made because of two conditions: (1) the necessity for some organization whereby contributions could be made in instalments to offset the sudden and large expense connected with illness for which the average employee is not prepared, and (2) the need for a more cohesive quality of service to replace a contract practice then in vogue, which did not take care of the employee's family or dependents. In different parts of the United States and Canada similar plans were in force, not only for employed groups but for numbers of people in circumscribed areas. In Europe different countries had adopted various forms of health insurance plans. It then was no surprise that these employees as a group should ask for some similar plan. With the cooperation of the management, a plan was instituted. The plan has one object only-the provision of medical services, including the accessory services such as hospitalization, X-rays, nursing, and necessary drugs and medicines. It is not concerned with cash benefits, sickness and accident payments, or any form of monetary return as the result of illness, but is simply an organization to provide medical services and pay for them from a central fund. It is a nonprofit organization and the only shareholders are the employees and their families who contribute and who in turn receive services. The Hollinger plan is limited to the employees of the Hollinger mine, who live in Timmins and the immediate vicinity. At first, the membership was voluntary. In the third year, it was made a condition of employment, with the proviso that at the end of any Association financial year an employee may withdraw if he wishes to do so. After withdrawal, he cannot again become a member until the end of the next Association year, and then only by the payment of the back dues. This step was taken to ensure continuity, and to prevent employees from withdrawing when well and reentering when faced with impending illness or operations. The employee himself is subject to medical examination on application for employment, and if accepted is subject to further examination by a specialist in chest diseases under the Workmen's Compensation Board of Ontario. Thus it is possible to exclude those who have heart disease, tuberculosis, or other disabling conditions when first employed. Wives and families of employees are not subject to medical examination but other dependents of an employee-mother, father, or other relative-who are declared by the employee to be wholly dependent upon him must be examined. The employee

Jan 1, 1944

By S. Weinig, J. Winter

The grain boundary adsorption of solutes as a function of bulk concentration and solution temperature was studied using internal-frictimz techniques. From the variation of the cor-responding energy of activation for the Phenomenon, the inter-actior2 energy between a solute atom and a high-angle boundary was calculated. Interaction energies in the range of 0.3 ev were obtained, and were used to obtain the actual concentration of solute at the grain boundary. In corroboralory creel, studies the direct grain boundary contribution to the total creep strain was measured. It was found that the interface creep varied with the type and magnitude of the solute adsorbed. Subscribing to the theory of their being energetically favorable sites at the grain boundary for solutes of both Positive and negative size deviations, ternaries were investigated in Which solutes of both types were present. A marked increase in the resistance to grain boundary creep was manifested. THE major difficulty which has been encountered in investigations of the grain boundary segregation of solutes has been the lack of a sufficiently sensitive method of measuring the amount of adsorbed solute at the boundary. For the general case of a high-angle boundary, no direct method of measuring the adsorption at the boundary has been found to date. Internal friction has been used in several studies of grain boundary adsorption1-3 and although it is somewhat indirect, it was demonstrated to have the necessary sensitivity. In this investigation the authors have used internal-friction techniques in conjunction with a study of the grain boundary contribution to the total creep strain. As both parts of the investigation were performed on the same specimens it was possible to combine a highly sensitive technique with a somewhat more direct method in order to obtain information about the adsorption phenomenon. From internal-friction studies the rate of increase of the activation energy was observed to be a function of the difference in size between the solute and solvent atoms. It was proposed that if Gibbs' adsorption isotherm is considered, i.e., where r is the excess solute at the boundary, c is the bulk concentration, and ay/ac is the change in grain boundary energy with bulk concentration, then AH b/ac must vary in the same way as ay/ac and therefore In this way a relative measure of the grain boundary adsorption of solutes is directly obtainable from in-ternal-friction studies. If the previous work in the field of grain boundary adsorption of solutes is examined, certain apparent information is desirable if the phenomenon is to be understood. The most important questions that must be asked are as follows: 1) Is the adsorption of solutes at the grain boundary an equilibrium process? 2) Can the Mott model of the grain boundary be used as a basis of setting up an elastic interaction between the grain boundary and solute atoms? 3) Is it possible to obtain an exact measure of the excess solute at the grain boundary as a function of temperature and bulk concentration rather than merely a relative measure of the adsorption 4) Are the conclusions obtained from an indirect method such as internal-friction studies meaningful in considering gross grain boundary effects such as creep? EXPERIMENTAL PROCEDURE The material used in this investigation was Bureau of Mines "superpurity" titanium (79 Bhn—1500 kg

Jan 1, 1960

THE members arrived at Ticonderoga, N. Y., at noon, Tuesday, October 15th, and were received by Mr. Cyrus Butler, Chairman of the Local Committee of Arrangements. During the afternoon the works of the American Graphite Company and the Horicon Iron Company were visited under the guidance of Mr. Butler, President of both companies, and of Mr. William Hooper, Superintendent. An excursion was then made, in carriages, to old Fort Ticonderoga, on Lake Champlain, after which the party were driven to the Rogers Rock Hotel, on Lake George. The first session of the Institute was held in the parlor of time hotel on Tuesday evening. Mr. Eckley B. Coxe, President of the Institute, opened the proceedings with the following address: I shall ask your attention, this evening, to a few reflections upon the subject of mining engineering as a profession in the United States, its past, its present, and its future, and its duties and oppor¬tunities with reference to the proper development of our great min¬eral resources. Thirty years ago, there were scarcely any mining engineers in this country, and but few in England, and there were no institutions where young men could be educated for the profession in the Eng¬lish language. France and Germany have been able for about a century to boast of mining schools of a high character, that number among their graduates such men as Humboldt, Weisbach, Rittinger, Combes, and Gruner. Of the few we then had worthy of the name of "mining engi¬neer," some had studied in the continental academies, and others were graduates in the school of practical experience, and had learned their profession in mines and smelting-works. Their work con¬sisted principally in making surveys and maps of mines and mining properties, geological reports, and analyses of ores ; but the mining engineer whom we often meet with now, who has studied chemistry, physics, mineralogy, geology, mechanics, and drawing; who is more or less familiar with machinery and its construction, and with the practical management of mines or smelting-works, and who is an expert in some one branch of his profession, would have been very difficult if not impossible to find in the United States. The induce¬ments held out to ambitious and talented young men to enter the

Jan 1, 1879

By Edward W. Parker

(Toronto Meeting, July, 1907.) NOTE.-The material from which this paper has been prepared was collected for the U. S. Geological Survey Bulletin, Contributions to Economic Geology, 1906, and appears also, though in somewhat more extended form without illustrations, in that publication. ALTHOUGH the briquetting of coals and lignites has been carried on for many years in Europe, and has reached a particularly high state of development in France, Belgium, and Germany, it has made comparatively little progress in the United States. The causes for the backwardness of the United States in this regard are several, and first among them has been the abundant supply of cheap raw fuel with which the manufactured article has to compete. With our millions of acres of coal-productive territory, from which the product can in most cases be cheaply extracted, it has appeared in many districts more economical to waste the slack or culm, which con¬stitutes a considerable percentage -of the product, than to attempt to save it at the additional expense required for briquetting. It is for this reason that the view in all sections of the anthracite-region of Pennsylvania is marred by the unsightly culm-banks which encumber the ground, and that in some of the bituminous-districts one sees huge piles of unmarketable- slack allowed to burn up in order to get rid of them. When the coal is of a coking quality, or when the slack can be used for steaming-purposes, these losses are not sustained, but many thousands of tons of what might be converted into usable fuel have been wasted every year simply because of the increased expense involved in its preparation.

Sep 1, 1907

By R. D. Parks

DESPITE the handicap of reduced production in many districts, the mining industry in 1938 forged steadily ahead toward solution of its minor technical problems and has of-defected major advances in several fields. In California hydraulic mining for gold, shut down for forty years, will shortly be resumed following revision of restrictive laws. Disposal of hydraulicked ground is to be regulated by settling dams so as not to interfere with agriculture. Gold mining has been aided also by the development of a new high-efficiency dry amalgamator which applies the Ramsay mercury separator to the original de Phily process. Based on the principle that crushed ore will follow a rod into a mercury bath, this simple device is primarily adapted to dry areas and is to be available in small, multiple units suitable

Jan 1, 1939

By Herbert Clark Hoover, Lou Henry Hoover

PREVIOUSLY I have dealt with the methods of separating silver from copper. There now remains the portion which treats of solidified juices ; and whereas they might be considered as alien to things metallic, nevertheless, the reasons why they should not be separated from it I have explained in the second book. Solidified juices are either prepared from waters in which nature or art has infused them, or they are produced from the liquid juices themselves, or from stony minerals. Sagacious people, at first observing the waters of some lakes to be naturally full of juices which thickened on being dried up by the heat of the sun and thus became solidified juices, drew such waters into other places, or diverted them into low-lying places adjoining hills, so that the heat of the sun should likewise cause them to condense. Subsequently, because they observed that in this wise the solidified juices could be made only in summer, and then not in all countries, but only in hot and temperate regions in which it seldom rains in summer, they boiled them in vessels over a fire until they began to thicken. In this manner, at all times of the year, in all regions, even the coldest, solidified juices could be obtained from solutions of such juices, whether made by nature or by art. Afterward, when they saw juices drip from some roasted stones, they cooked these in pots in order to obtain solidified juices in this wise also. It is worth the trouble to learn the pro- portions and the methods by which these are made. I will therefore began with salt, which is made from water either salty by nature, or by the labour of man, or else from a solution of salt, or from lye, likewise salty. Water which is salty by nature, is condensed and converted into salt in salt-pits by the heat of the sun, or else by the heat of a fire in pans or pts or trenches. That which is made salty by art, is also condensed by fire and changed into salt. There should be as many salt-pits dug as the circumstance of the place permits, but there should not be more made than can be used, although we ought to make as much salt as we can sell. The depth of salt-pits should be moderate, and the bottom should be level, so that all the water is evaporated from the salt by the heat of the sun. The salt-pits should first be encrusted with salt, so that they may not suck up the water. The method of pouring or leading sea-water into salt-pits is very old, and is still in use in many places. The method is not less old, but less common, to pour well-water into salt-pits, as was done in Babylon, for which Pliny is the authority, and in Cappadocia, where they used not only well-water, but also spring-water. In all hot countries salt-water and lake-water are conducted, poured or carried into salt-pits, and, being dried by the heat of the sun, are converted into

Jan 1, 1950

By AIME AIME

THE official opening at the 134th general meeting of the Institute was held on Oct. 6, but it was prefaced by two round table conferences on Oct. 5. The open-hearth group held the fourth of their semi-annual conferences at the William Penn Hotel, devoting the morning session to discussing a paper by R. L. Cain on the "Manufacture of Forging Steel by the Open-hearth Process," and the afternoon to discussing P. H. Shaeffer's paper on the open-hearth charge. At the Bureau of Mines, a round table conference on the combustibility of coke was held on Tuesday morning, and the afternoon was devoted to a similar conference on the testing of coke. The formal opening session of the meeting assembled in the Music Hall of Carnegie Institute at 10.30 a. m. Graham Bright, chairman of the Pittsburgh Section; called the meeting to order and presided. President Taylor welcomed the visiting members and guests to his home city and reviewed briefly the advancement of mining in the past half century during which, for ex- ample, the coal output had increased from 53,280,000 tons to 523,357,000 tons per year. He emphasized the important part Pennsylvania played in mining and brought out the principal changes that had taken place in methods. In part, his remarks were as follows: The centennial year, 1876, found the coal business of. this country, as a whole, producing 53,280,000 tons, of which amount the bituminous mines of this State yielded 24 per cent. In 1925, this country produced 523,357,000 tons of coal, of which Pennsylvania produced 24 per cent.

Jan 1, 1926

By Earl E. Hunner

At the end of the year 1914, the main North Star incline shaft had reached the 6300-ft. level, and encountered a vein dipping southwest, or exactly opposite to the North Star. Subsequent development failed to find the North Star vein continuing beyond this intersection, so the 6300-ft. level proved to be the bottom level of the North Star vein, and very little ore was found below the 5300-ft. level. The new vein was called No. 1 vein. Development work carried on for the next 10 years discovered a third vein, called No. 2, branching off about 1200-ft. to the east, with a north-south strike and a west dip. No. 1 vein had about 900 ft. of backs above the 6300-ft. level before reaching the boundary line of the property, and No. 2 vein died out about 800 ft. above. During these 10 years, the money spent on development was increased from $54,000 in 1914 to $184,000 in 1924; the ore reserves steadily diminished until it was evident that the mine must close down unless by some means a large tonnage of ore could be developed quickly. Problems and Plans In order to understand what follows, the general layout and equipment of the mine as it was at this time must be briefly described. Fig. 6 indicates the relative positions of the shafts. The North Star (incline) shaft extends from the surface to the 6300-ft. level following the vein, with an average pitch of 26", between limits of 11" to 38. There is at present no hoisting equipment in this shaft between the 2700 and 4000-ft. levels. The Central (vertical) shaft connects with the North Star shaft at the 4000-ft. level, at a vertical depth of 1600 ft. In two compartments of this shaft 4-ton skips made a vertical turn of 15 ft. radius at the 4000-ft. level and ran down the incline to the 6300-ft. level. A cage operated in the third compartment to the 4000-ft. level. Men and supplies were transferred to a truck running on a third track down the incline shaft to the 6300, operated by an electric hoist on the 4000-ft. station. When the shifts changed double-deck cages were substituted for the skips in the vertical shaft, but they stopped at the 4000-ft. station. The truck to 6300 carried 22 men, and it required 8 min. to make a trip down and back. This arrangement was satisfactory as long as a fairly large proportion of the work was

Jan 1, 1930

By Herbert Clark Hoover, Lou Henry Hoover

QUESTIONS of assaying were explained in the last Book, and I have now come to a greater task, that is, to the description of how we extract the metals. First of all I will explain the method of preparing the ore1 ; for since Nature usually creates metals in an impure state, mixed with earth, stones, and solidified juices, it is necessary to separate most of these impurities from the ores as far as can be, before they are smelted, and therefore I will now describe the methods by which the ores are sorted, broken with hammers, burnt, crushed with stamps, ground into powder, sifted, washed, roasted, and calcineda.

Jan 1, 1950

Jan 1, 1880

By Norman C. Stines

Russia's mineral potential is a secret that has been effectively kept by the Iron Curtain. There is no conclusive data and because of its extreme importance to the Free World, the subject is greatly discussed. Opinions range from those presented by Paul Tyler in his article "Russia's Mineral Potential," June issue of MINING ENGINEERING to those of Norman C. Stines, presented herewith. Mr. Stines is a consulting mining engineer of Los Gatos, Calif. He was in Russia, China, and Manchuria from 1909 to 1918 as a mining executive. From 1917 to 1919 he served as assistant military attache Intelligence Branch U. S. Army in Petrograd, Russia.

Jan 11, 1951

By David B. Reger

New discoveries of gas in the southern counties featured the petroleum industry in West Virginia during 194;. Drilling for oil increased slightly over 1944 and a small increase of initial production resulted. Out of 28 wildcats drilled, there were 16 gas discoveries and 12 dry holes. No commercial oil was found in the 28 wells.

Jan 1, 1946

By D. W. Brunton

Discussion of the paper of D. W. Brunton, presented at the Spokane meeting, September, 1909, and published in Bulletin No. 33, September, 1909, pp. 837 to 855. WILLIAM' KENT, New York, N. Y.:-The Institute may congratulate itself on the opportunity of reading the splendid address of President Brunton. It is au admirable summary of the progress that has been made in the mining and metallurgical arts in recent years. The paper rightly give's the chief credit for this progress to the aid which has been rendered to these arts by the advances in mechanics, chemistry, and electricity. It is notable that most of the headings in Mr. Brunton's address refer to the work of the mechanical engineer, the electrical engineer, and the chemist, rather than to that of the specialist in mining-operations. It seems that. the most successful mining engineer of the present day is the one who makes the most intelligent application of the inventions and designs of engineers and others who are not directly engaged in mining. A tabulation' of the headings of the address, grouped as below, shows this most clearly. Work of the Mechanical Engineer-Rock-drills, hoisting-machinery, tramming, pumping, ventilation, dredging, sampling, concentration, briquetting, fume-recovery. Work of the Electrical Engineer-Electric machinery for hoisting, pumping, tramming, lighting and signaling, electric . transmission, electric smelting. Work of the Chemist and Metallurgist-Explosives, chlorination, cyanidation, roasting, lead-smelting, and copper-smelting. Work of the Geologist-Economic geology. Work of the Mining Engineer-Mine-mapping, surface-mining, timbering, tunneling; and planning and supervision of the work in general. The mining engineer of the present day, who is in responsible charge of a large plant, finds his chief work not in doing

Jan 1, 1910

By R. W. Nash, A. E. Schwaneke, V. R. Miller

The Bureau of Mines developed a detector for controlling sorting devices to separate the copper-bearing fragments from the barren portion of Michigan native copper and western prophyry copper ores. A successful sorter could be used to preconcentrate the ore and eliminate costly hoisting or hauling of waste. An induction balance unit was developed and used in sorting tests on crushed sized - 2.5 + 1. 3-cm (- 1 + 1/2- in.) ores from the Kingston (0.9% Cu) and Centennial (1.6% Cu) mines of Upper Michigan. Concentrates of 4.0% and 7.5% Cu, respectively, were obtained at recoveries of 85 and 80% of

Jan 8, 1978

By J. B. Tyrrell

A short time ago I paid a visit to the alluvial gold fields on the tributaries of the Chaudiere River in Beauce County, Quebec, in company with A. 0. Dufresne, late manager of the Champs d'or Rigaud-Veaudreuil, and now assistant to the Superintendent of Mines of the Province of Quebec. As the conditions under which the gold occurs in this district are not very generally known, and present some interesting features, a brief description of these conditions, and a consideration of the causes which gave rise to them, may be of interest to other mining engineers. During the latter half of last century the country was visited by many mining engineers and geologists, and many references to it may be found in the reports of the Geological Survey of Canada between 1848 and 1911. The most important of these are by J. A. Dresser and J. Keele and the late Robert Chalmers. The Department of Colonization and Mines of the Province of Quebec also published a report with map on the district by J. Obalski. From the earliest times the valley of the Chaudiere River formed one of the main avenues of approach to the St. Lawrence in the vicinity of Quebec from the country to the south as far as the seaboard of the States of Maine and Massachusetts. The Indians had a well-known trail along the banks of the stream, and armed troops and foraging parties constantly moved backward and forward along it between Quebec and New England in those insecure times before the ceding of Canada to Great Britain. Even yet the natural advantages of this old military route are recognized, and the government of the Province of Quebec has now under construction along it a magnificent highway from Quebec to the International Boundary Line, which is to form part of a through highway from that city to Boston. The land along the valley is naturally well suited for agriculture, and about the end of the eighteenth and the beginning of the nineteenth centuries farmers began to go back from the St. Lawrence, and to occupy the higher lands along the upper portions of the Chaudiere Valley. This settlement has gone on until now the country is peopled with a prosperous agricultural population.

Jan 1, 1915

By K. A. ACKLEY

The petroleum industry experienced a year of satisfactory accomplishment in Oklahoma during 1945. Crude oil production was increased, a new record for recent years was established in well completions, and refinery operations were maintained at a maximum level. Daily average crude oil production increased to 382,000 bbl., reflecting a 13.5 per cent gain compared with production during the previous pear. Total wells drilled during 1945 amounted to 2556, a gain of 28.7 per cent over 1944 Refinery throughout averaged 187,500 bbl. daily, an increase of approximately 4 percent over the preceding year.

Jan 1, 1946

By Betty J. Laswell, Gerald W. Laswell

The stepped-up pace of US open-pit and surface mining during the 1970's is a direct response by mining firms and equipment manufacturers to rising costs and declining ore grades. In the race for bigger and more efficient machines, rotary drills have emerged as the foremost leader in primary drilling at major US surface operations. At least 12 different manufacturers now offer rotary rigs in the 102- mm-diam. (4-in.) or greater blasthole size range. With capital investment for the larger units quickly approaching $1 million, the question is asked, "What's been the performance record to date of rotary drill rigs operating in North America?" To answer that question, a comprehensive study of rotary blasthole drills was conducted which qualitatively reveals various problem areas inherent in the rotary drill market and indicates some new directions for improvement.

Jan 6, 1978

By George J. Young

(Cleveland Meeting, October, 1912.) I. GENERAL. THE recurrence of mine-fires in Nevada during the past decade is not only a matter of interest, but also one of considerable concern to engineers and mine-managers. The more important fires may he enumerated as follows: Forman Shaft fire., Gold Hill, April 21, 1903 ; shaft-house, machinery, and shaft, destroyed; loss estimated at $50,000.; Cause Unknown. Union Shaft fire, Virginia City, July 14, 1904; shaft-house, machinery, and shaft in part destroyed; loss estimated it $100,000; cause of fire stated as the careless throwing of a match in the rope-house. Sutro Tunnel fire, Virginia City, Jan. 27, 1909 ; 700 ft. of tunnel-timbering destroyed, and direct damage of $10,000; cause ' probably electric wires." Belcher Shaft fire, Gold Hill, Aug. 9, 1910; shaft-house destroyed, machinery ruined, and upper part of shaft damaged; damage, $25,000; no cause given. Belmont Mine fire, Tonopah, Feb. 23, 1911; fire started in winze ; 17 men killed. Giroux Mine fire, Kimberly, Aug. 23, 1911 ; fire originated iii shaft-station from unknown cause; 7 men killed, and $34,¬521 damage caused. (NOTE 1.-On June 11, 1912, some time after the present paper was written, a fire broke out in the pump-room on the 2475 station of the Ward shaft, Virginia City. This fire was caused by the short-circuiting and exploding of the starting-switch on No. 5 pump. The oil in the switch was scattered about and set fire to the timbers and laming of the pump-room. The pump-roan in charge notified the surface, and the * Professor of Mining and Metallurgy, Mackay School of Mines.

Oct 1, 1912

By Owen Thornton

Recently equations have been presented by Rose and Bruce' and by Rose², showing how the relative permeability of a reservoir rock may be determined from the capillary character of the rock. In particular, equations were developed to show the relationship between capillary pressure and the effective permeability to the wetting phase in a poly-phase flow system. The equations are as follows (nomenclature the same as in the Rose and Bruce paper) Rose and Bruce assume that the average length of path (L,), which the wetting fluid follows in flowing through a porous media is independent of the saturation to the wetting phase, so that 1 is a constant dependent only on the k rock, and the permeability to the wetting phase is a function of the saturation and of the capillnry pressure: In measuring the flow of ekctric current through partially saturated core samples, it has been observed that the electrical resistance usually is not a simple linear function of saturation. This fact indicates that the average length of path in the flow of electric current is not independent of saturation, but rather that the tortuosity of the path depends upon the average saturation to the conducting fluid as well as upon the characteristics of the rock. itself. Inasmuch as the flow of fluid and the flow of electric current in many respects are analogous, it may be indicated further that the length of path for fluid also may not be independent of saturation. The following relationship can be derived to express the resistance to flow of electric current through a core sample partially saturated with conductive wetting phase, the non-wetting phase being non-conductive: where L is the average length of path followed by the current in flowing through a length L of partially saturated core, where L is the length of current path when the core is fully saturated, and where Rs and R, are the specific resistivities of the partially saturated and saturated core sample, respectively. It will be noted that R., the specific resistivity of the core sample when S, = 1.0, is equal to the "formation resistivity factor"' multiplied by the specific resistivity of the saturating fluid. If it be assumed that the average lengths of path for fluid flow and for the flow of electric current are the same, then equation (5) may be combined with equations (l), (2) and (3) to give the following relationship: The above equation suggests including a correction for tortuosity when calculating the relative permeability of a reservoir rock to a wetting phase. The correction factor may be obtained from the resistivity-saturation relationship. For instance, the following calcu- lations are obtained for the unconsoli-dated sands described by Leverett Kw Kw Sw R°/Rs Pt/Pc¹ (Calc.) (Obs.) 0.30 0.08 0.88 0.02 0.0 0.40 0.16 0.94 0.06 0.04 0.50 0.27 0.97 0.14 0.11 0.60 0.40 0.98 0.26 0.21 0.70 0.53 0.98 0.39 0.35 0.80 0.68 0.99 0.57 0.54 0.90 0.84 0.99 0.77 0.76 1.00 1.00 1.00 1.00 1.00 It will be noted that the agreement between the calculated points and the observed data is rather good. Further investigation of the above method for obtaining relative permeabilities may be merited. For many sands within specified ranges of saturations the following relationship has been found to hold approximately': — =SW"......(7) Rs The exponent n in the above equation has been found to equal two for many sands so that equation (6) reduces to the following: The writer acknowledges the permission of The Texas Co. to submit this note for publication. 1. Walter Rose and W. A. Bruce—Jnl. of Pet. Tech., Vol. 1, No. 5, p. 127 (1949). 2. Walter Rose—Jnl. of Petr. Tech., Vol. 1, No. 5, p. 111 (1949). 3. G. E. Archie— -Trans. AIME, 146, 54 (1942). 4. M. C. Leverett— Trans. AIME, 142, 152 (1941). 5. M. C. Leverett—Trans. AIME, 132, 149 (1939).

Jan 1, 1949