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By Edel Moldenke

Burma has long been known for its ruby, tungsten, and tin deposits, and, lately, for having the largest lead-zinc mine in the world, the Bawd-win mine of the Burma Corpn. All the coal used, however, is imported from Calcutta; this is a bituminous coal of about 11,000 B.t.u., 24 per cent. ash, and costs about $8 per ton. Bituminous coal has not, thus far, been found, but many lignite deposits are known. The most promising lignite deposits are in the Namma field, Fig. 1, situated in the Northern Shan States of Upper Burma, about 30 mi. south of Lashio, the terminus of the Burma Railway, 750 mi. north of Rangoon. The

Jan 1, 1922

[Trans. No. Place Date Vol. Page 1, Wilkes-Barre, Pa.* .... May, '71.. 1 3 2. Bethlehem, Pa Aug., '71.. 1 10 3 Troy, N. Y Nov.,'71.. 1 13 4. Philadelphia, Pa Feb., '72.. 1 17 6. New York, N. Y •.... May, '72.. 1 20 6. Pittsburgh, Pa..:.Oct., '72.. 1 25 7. Boston, Mass Feb., '73.. 1 28 8 Philadelphia, Pa.' May, '73.. 2 3 9. Easton, a Oct., '73.. 2 7 10. New York, N. Y Feb., '74.. 2 11 11. St. Louis, Mo.* May, '74.. 3 3 12. Hazleton. Pa Oct.. '74.. 38 13. New Haven, Conn Feb., '75.. 3 15 14. Dover, N. J.' May, '75.. 4 3 16. Cleveland, 0 Oct., '75.. 4 9] [ ]

Jan 1, 1925

The largest variety of asphalt and related bitumen deposits in this country is found in Utah. Utah is one of the few places in the world where the hydrocarbon minerals, gilsonite or uintaite, wurtzilite (trade name elaterite) and ozokerite are produced. These bitumens occur in an area embracing nearly 10.000 square miles in eastern Utah near the Colorado line. This area is largely in the western part of the Uintah basin. The bitumens are in the Tertiary horizon in the various divisions of the Eocene series. Cilsonite is an asphaltite derived from petroleum, wurtzilite is an asphaltic pyrobitumen derived from petroleum, and ozokerite is a native mineral wax resulting from the metamorphosis of paraffinaceous petroleum.

Jan 1, 1925

By L. L. Anderson, R. E. Wood, W. H. Wiser

Western bituminous coal can be processed to low sulfur liquid fuels by fast reactions. A process (LEFCO) under development at the University of Utah uses coal and catalyst under hydrogen pressure to convert 60 to 70%of the coal matter to fuel liquids and gases. Coals have been processed in small diameter (less than %in.) tubes and at reaction residence times of less than 10 secs. Effects of process variables on the yield and quality of products have been studied. General features of the process and the properties and characteristics of the products produced are presented. Special features of the process that distinguish it from other liquefaction processes under development are also discussed.

Jan 1, 1977

By Luis Toron, Salvador Cortes-Obregon

THE Oaxaca coal fields, shown in Fig. 1, are located in the Alta Mixteca region in the states of Oaxaca, Puebla, and Guerrero. Known outcrops are scattered over 3125 square miles. It is probable that further exploration will reveal a more extensive area of deposits. The region is of great importance to Mexico, as at present the only sources of coal are the fields near the U. S. border. Steel mills are also located in the North, and finished products must travel 600 to 800 miles to the area of consumption in central Mexico. The oaxaca coal, only 120 miles south of Mexico, D.F., lies close to several iron ore deposits. If this

Jan 1, 1955

By Adrian C. Dorenfeld, John T. Oleksy

Fuel problems of two lesser developed countries (LDC 's) are presented. In particular, the paper reviews cement technology and the fuel-intensive cement industries of the Philippines and South Korea. Based on current financial and cost data, analyses are presented of the proposed substitution of high-sulfur and slow-sulfur American coal in place of fuel oil. The analyses show that economic substitution of coal for oil is not only based on relative prices for coal and oil, as expected, but also to be an inverse function of degree of intensity of energy use, and a direct function of financial incentives such as accelerated depreciation, taxes on the savings made by the use of coal, and cost of capital.

Jan 4, 1979

Henry D. Hibbard, High Bridge, N. J. (Communication to the Secretary): There is one chemical factor which has not been considered in the author's tabulation of tests, but which is none the . less important because it cannot be practically estimated, and that is the element oxygen. This element has been, and probably will continue for some time to be, one of the great causes of the continual discrepancies between the chemical and physical properties of steel. Probably oxygen occurs, in important proportions, only in soft steel, such as that which we are now considering. In this steel its physical effect is to diminish tensile strength and elongation. The percentage of oxygen in the steel, under working-conditions that are as uniform as possible, is likely to vary inversely as that of the manganese, or perhaps, and more probably, it may bear even an inverse geometrical ratio to the manganese-content. At all events, to follow the author's plan, the line representing the loss of strength due to oxygen is probably a curve. Plotted by itself, the line would probably be straight; that is, the decrease in strength would be proportional to the increase in oxygen, but if the results were superposed on the percentages of manganese, they would give a curve, because the percentages of oxygen increase faster than those of manganese decrease. Were the oxygen-line to be developed and added to the diagram, it would seem that the manganese-line should then be straight. Due allowance for the effect of oxygen, therefore, would modify two features of the paper. It would increase the figure for the strength of pure iron from 38,000 to about 45;000 pounds per square inch, and it would straighten out the manganese-curve. The manganese-line in the paper is curved between 0.50 and 0.20 per cent. Above 0.50 per cent. it is straight, which may be ascribed

Jan 1, 1893

By M. J. Hordon, M. A. Wright

The well-defined increase in fatigue life observed o many metals cyclicly strained at vacuum levels below 10-1 to 10-3 torr has been attributed to the critical retardation of oxygen or water vapor chemisorption at the crack tip during crack propagation.1-3 In the absence of strongly adsorbed surface films, crack re-welding during cyclic compression or dislocation escape from the plastic zone around the crack tip has been proposed to account for the observed decrease in the rate of crack growth. The increase in the critical pressure required for the transition in crack growth rate with temperature experimentally determined for aluminum was found to be generally in accord with the adsorption rate model.4 However, although the adsorption mechanism would also predict an increase in transition pressure and fatigue life with increase in cyclic loading rate, and such effects were noted by Snowden5 for lead and Hordon3 for aluminum, the opposite results were reported by Kramer et al.B in studies on aluminum. The present note describes some recent measurements of the fatigue properties of 1100-H14 aluminum at low pressures to determine the specific effect of cyclic strain frequency in the transition pressure range. Flat cantilever-type specimens of 1100-H14 aluminum shaped to produce a uniform strain gradient along the gage length were tested in reverse plane bending at constant deflection amplitudes in two independent multi-specimen vacuum fatigue systems. One series of tests using 2-in. gage length specimens was conducted in an ion pumped apparatus with 107 torr and 50 cps capacity, denoted as Unit I, utilizing fixed mechanical cams to impose the strain amplitude. An independent test series using shorter 1-in. gage length specimens was conducted in a cryopumped apparatus designed for extremely low pressures below 10-10 torr, denoted as Unit II, using an electromechanical vibrator at non-resonant frequencies up to 150 cps to provide the deflection. Both vacuum fatigue units and associated test procedures have been described previously.3'7

Jan 1, 1969

By Robert Lepsoe

It is generally realized that in cyaniding the precipitation efficiency of zinc dust is due to the fine division or extended surface of its metallic particles; but frequently it is thought that the presence of other metals, say 2 to 3 percent. lead, is advantageous, causing more complete precipitation. The results of testing about fifty brands of commercial zinc dust have led to the conclusion that there is a distinct relation of precipitation efficiency to fineness and that the effect generally can be estimated by examining the size of metallic particles. The presence of lead was not found to be of any importance. Specifications Generally the term "97 per cent. to pass a 350-mesh screen, 95 to 97 per cent. uncombined metallic zinc" is used by the leading European exporters. Among the many methods of determination of metallic zinc, I have found the iodine test (iodine in potassium iodide) very satisfactory and rapid. It has been controlled by the other methods, samples of the same product having been sent to three different analysts: Iodine method................... 98.11 per cent. metallic zinc, Volumetric method.............. 07.63 per cent. metallic zinc, Ledoux Co., New York Bichromate method.............. 08.16 per cent. metallic zinc, Watson Gray, Liverpool. England Bichromate method.............. 98.20 per cent. metallic zinc, Norway Inst. of Tech., Trondhjem Determination of Precipitation Efficiency The method devised by W. J. Sharwoodl was used. The method proved to be satisfactory, the tests being merely for the comparison of different samples, hence the personal factor in manipulation was eliminated. As nearly all tests showed more zinc in solution than was accounted for by the silver precipitated, the term "dissolved zinc" was introduced—it means zinc dissolved by the action of cyanide and oxygen: Zn + 4KCN + H2O + O = K2Zn(CN)4 + 2KOH; or more probably, resolution of its equivalent precipitated silver, as tests stirred two hours showed more "dissolved zinc" than those stirred

Jan 1, 1925

By A. J. Lanza

IN view of the immense amount of attention that silicosis has received in this country in the past few years, it is timely to review the status of the silicosis problem at present. Who gets silicosis? The individual exposed to the inhalation of free silica dust. The effects upon the individual depend upon the amount of silica inhaled or, in other words, the severity of exposure, rather than upon any special variation or susceptibility among those exposed. A considerable amount of study has been given to determine what may be the role of predisposing causes in the development of silicosis. To men-tion one instance, at the Picher Clinic careful records were kept of all previous illnesses of the men examined as well as abnormalities present at the time of examination. Examinations of over 27,000 miners were made during the years the clinic was conducted under governmental auspices-a very fair sized sample. The general conclusions from all this work were that the incidence of silicosis is not appreciably influenced by racial, structural, or other inherent qualities; it is influenced by acquired defects-particularly as these affect the lungs. That is to say, the average run of human beings respond similarly to similar exposures to silica dust and those whose lungs are already impaired by tuberculosis or other pulmonary disease acquire silicosis more readily than those with healthy lungs. It may well be, and there is some clinical evidence in support, that negroes acquire silicosis more readily than do whites, but the infection factor has not been so carefully studied among negroes exposed to silica as it has among whites. We know that tubercle infection is more prev-alent among negroes than among whites. There may be other factors concerned in the development of silicosis in negroes as compared to whites, but there is not available information upon which to base posi-tive statements.

Jan 1, 1937

By Edwin Ludlow

ONE of the most unusual features in connection with the strike of the union coal miners in the bituminous fields, now in its sixth week, is that the public interest seems to have completely died out. There is nothing on the front page and very little on any other page of the daily newspapers in connection with the strike. The United Mine Workers' officials must be rather disappointed to find that the only way in which they are being featured in the papers at present is in the reports of the trial for treason that is going on in Charlestown, West Va., against the local leaders of that organization for their responsibility in connection with the attack of the miners' army last summer against the non-union mines of Logan and Mingo Counties. Recent reports state that there are 13,000 cars of coal standing on the sidings at union mines for which no billing has yet been found. The output of the non-union mines has been gradually increasing but has never reached the maximum that they are capable of producing, owing to their inability to obtain enough orders to make it possible to run full operating time. The, present output is estimated at, 4,500,000 tons a week. It is possible, with a full car supply and full demand, to bring this output up to approximately 6,000,000 tons per week, and it is very doubtful whether, at this season of the year when probably there is less consumption of coal than, at any other season, the requirements of the country are greater than the 6,000,000 tons which the non-union mines are capable of producing. It would appear, therefore, that there is no immediate prospect of any settlement of the bituminous strike, and there is certainly no reason why the operators of the union mines should show any anxiety to begin operations as long as they have unbilled coal standing on their sidings.

Jan 6, 1922

By Clemens Jones

THE analytical history of phosphorus in its relation to the metallurgy of iron is an interesting study, the progress of which runs parallel with the development of the greatest industry in the world. Without the means of finding out how much phosphorus crude pigiron contained, the Bessemer steel process would have been impossible. To do this was originally tedious and slow work. On the other hand, the " direct" process of to-day, as well as the various special processes for steel or iron, have demanded the utmost rapidity in the operations of analytical chemistry. In general, any rapid process for the conversion of unrefined metal into a product of standard composition depends upon the rapidity of some accurate means employed to control it. Moreover, in our modern practice, it is not improbable that the differences in physical properties among the various makes of iron or steel are affected, if not produced, by the use of different methods of analysis. Recourse is always had for correction to the ((standard methods," but I incline to think that these methods are susceptible to error. It is very certain that the system of duplicates would not be resorted to, if the fact were otherwise. Even when duplicated, under the most careful and skilful manipulation, these standard methods produce disagreements. In proof of statements like these, which may sound. heretical, I hope, further on, to cite some evidence worthy of attention. I do not now mean to lay claim to the distinction of discovering the ultimate corrective. That result will come, no doubt, in. time, as the product of the experience of many workers. In the case of phosphorus, as of the other ingredients of iron or steel, a great deal has been done to accommodate the methods of analysis in rogue to the growing necessity for more rapid procedures: Much of this work has concerned what might be called the incidents of method. There is no better example of the accumulation of these incidental improvements than the work done on phosphorus; and I

Jan 1, 1890

By Wilbur Nelson

Little drilling has been done in Kentucky and Tennessee in 1923, with the exception of the Kettle Creek area on the Kentucky-Tennessee line. Oil prices fluctuated between $2.86 and $1.36 Per bbl. for light oil. The Kentucky production was slightly over 8,000,000 bbl., being 1,000,000 bbl. less than during 1922. Tennessee production was approximately 8500 bbl., being a decrease of 1000 bbl, over. 1922. During 1923, the first producing well was brought in, in Clay County, Tenn. Production in Tennessee will undoubtedly increase considerably in 1924, and Kentucky production will probably increase slightly. THE year 1923 has been a dull period in oil development in Kentucky and Tennessee, with the exception of the Kettle Creek area along the Tennessee-Kentucky line, in Clinton and Cumberland Counties, Kentucky, and Clay County, Tennessee. The price of oil during the year has been so low that wildcatters have shown little interest in drilling. At the beginning of the year, light oil sold for $2.31 per barrel and medium oil for $2.06 per, barrel. Prices increased to the highest point for the year in February, when light oil brought $2.86 per barrel and medium oil, $2.61. In April, prices had declined 35 c. while in May an additional decline of 25 c. went into effect. During June, prices declined 20 c. per barrel; during July, 45 c. per barrel; remained stationary during August and September, and dropped during November and December to the low price of $1.36 per barrel for light and $1.21 for medium oil. At present, an increase of 29 c. has brought the price of light oil up to $1.55, and indications are that the price will continue to increase during the coming months. It can readily be seen that during 1923 the price of oil was such as to prevent any drilling except that necessary to hold leases and to maintain production enough to take care of overhead expenses.

Jan 3, 1924

By Fred W. Gordon

The North Chicago Rolling-Mill Co., of Chicago, have four furnaces at South Chicago, built during 1881. Each furnace is 20 feet diameter of bosh, and 75 feet total height, the hearth being 11 feet diameter, and the top 15 feet 4 inches. They are blown through seven 7-inch tuyeres placed 5 feet 6 inches above the hearth level. Cubical contents, 15,000 cubic feet. Each furnace is supplied with 2 blowing engines, 84-inch blowing cylinder, and 36-inch steam cylinder, and 54-inch stroke. These two have one jet-condenser worked by an auxiliary pump. The blast for each furnace is heated by the aid of three Whitwell fire-brick stoves, each 21 feet diameter and 60 feet high. In the batteries of boilers furnishing steam for four furnaces there are 36 double-length boilers, 76 feet long, 48 inches diameter and 16,000 square feet heating-surface. The plant was designed to produce 3600 tons per week, or 900 tons for each furnace, and was fitted as above with such engines, boilers, and hot-blast stoves as were thought requisite for that production ; hence, calculated from the present make—not the least remarkable feature is the economy of construction—there are less engines, less boilers, and less hot-blast power for the iron made than at ally plant within my knowledge, or it could to-day be duplicated for less money per ton of iron made per week than could any plant now in existence, whether using fire-brick or cast-iron stoves for heating the blast. This is a practical demonstration of my assertion in a paper on fire-brick stoves, read before the Institute," that the application of fire-brick stoves in construction really lessens the first cost. In view of the statements just made, I must be most emphatic in assuring the members that nothing is strained or overburdened.

Jan 1, 1886

By Frank A. Wilder

The most important process in a gypsum mill is calcining the crude mineral. There seems, however, to be little progress or change in calcining methods. This would not be surprising if the industry was not, in other ways, developing. The demand for gypsum in its various forms, however, is growing rapidly. The output has more than doubled in six years, while the value of gypsum products, through the introduction of higher priced. specialties like wall board, has nearly trebled in the same period. In other industries, under somewhat similar conditions, calcining in rotating cylinders, either by direct or indirect heat, has replaced the method that still prevails in gypsum mills. Efforts were made to use rotary calciners in manufacturing plaster of Paris in the early days of the industry in America; 25 years ago rotary calciners were in use in Germany. At that time there was great diversity of opinion in regard to their merit. In 1923, the output of calcined gypsum in the United States was 3,101,378 tons. About nine-tenths of this material was calcined in kettles, the remainder in rotary calciners. The ratio was about the same 10 years ago. During these 10 years, rotary calcining made relatively no gains, and there were no important changes in the construction of kettles. In their manipulation, the only change of consequence was in connection with the length of time that the gypsum is left in the kettle. For wall-plaster purposes, all producers who had not previously done so changed from second-settled to first-settled calcined gypsum, thereby reducing production costs and improving the plasticity and sand-carrying capacity of their plaster. Nevertheless, in the few mills in which they were installed, rotary calciners continue to operate, with possibly one or two exceptions, and to be highly successful. In these 10 years, the Cummer type of rotary calciner has disappeared. All rotaries now used are of the cement-mill type with a diameter of 6 or 7 ft. and length of 80 to 120 feet.

Jan 1, 1925

The resignation of Herbert Hoover, Director General of Relief in Europe, from his post as Chairman of the Board of Directors of the Food Administration Grain Corporation, in which capacity he had served for nearly two years; and the reorganization of the corporation under the name of the United States Grain Corporation, with Julius Barnes, United States Wheat Director, as its new head, took place at the annual meeting of the stockholders, held in New York, July 1. This action on the hart of Mr. Hoover is believed to be one of the first steps in his intended withdrawal from public service upon the conclusion of the war service of the various departments of the Food Administration, or as soon as they shall have been absorbed by other agencies. The Grain Corporation has been, for the past two years, a vast collection and distribution agency. Its function has been to assist in supplying to the Allies and the American Army and Navy large quantities of wheat, wheat flout, and other foods, with very little disturbance of American prices, and with such an even control of American distribution that reserves from one crop to another have been brought down to the lowest possible compass and without the dvelopment of actual scarcity anywhere in the United States. In the year just past, it carried on all the buying and the shipping for, the Belgian Relief Commission, until the commission retired on May 1 and the Belgian Government itself undertook its own overseas supplies. During the twenty-two months of its existence the corporation had disbursed $3,500,000,000 and collected an equal amount, selling for over-seas shipments commodities valued at $1,800,000,000, at an operating expense of about $3,250,000, or one-sixth of 1 per cent. During this time it has not lost a single dollar through fire loss.

Jan 8, 1919

TWENTY-FOUR of the 28 local sections and the two divisions of the Institute were represented at the meeting. Three sections failed to appoint delegates and two of those appointed failed to attend the delegates' meeting proper. Four sessions were held, two on Monday and two shorter adjourned ses-sions on Tuesday and Wednesday. Even at the end many things remained to be said and, in view of the amount of time the delegates lost from technical ses-sions the feeling was general that next year it would be advisable to hold their meeting the day before or day after the general meeting. Every part of the country was represented from Boston to Los Angeles and Seattle to Washington. All phases of Institute work and policy were taken up in the most informal way and the delegates will carry back to the sections, as they brought to headquarters, many ideas that will prove useful and stimulating. The time was divided between reports by the delegates on section activities and reports by officers of the In-stitute and of the various joint activities on the work at headquarters : A. D. Flinn told of the work of Engi-neering Foundation; W. V. Brown discussed the Em-ployment Service; J. A. Sohon explained what the Library is doing; T. T. Read told how the sections could help MINING AND METALLURGY ; H. Foster Bain discussed Institute affairs in general and asked and answered questions. An interesting new feature of the meeting was the appearance by request of Directors Turner and Smith of the U. S. Bureau of Mines and U. S. Geological Survey to answer inquiries as to the needs and work of their Bureaus. So much attention had been paid this year by the western sections to the diminished funds made available at Washington for research on mining problems that many questions came up. The accom-panying figures epitomize the answers.

Jan 3, 1928

By William F. Blake

In September I contributed an article upon Columbite in the Black Hills of Dakota to the American Journal of Science. I had not at that time seen the paper by Professor Charles A. Schaeffer, of Cornell University, upon the occurrence of tautalite in the same region," or I would have gladly made reference to it. His analysis, proving the entire thence of columbic acid, shows that the specimen he analyzed, at least, should be called tantalite, and not columbite, if the distinction between these two closely related species is to be maintained. It is hard to say where the line is to be drawn, in such cases, between two minerals, when the specific characters and the composition are so nearly the same. If the name is to be determined by the relative amounts of tantalic and columbic acids, what shall we call the mineral when these acids are present in nearly equal quantities? Preference was given in this case to the name columbite, for the reason that the specific gravity, as ascertained by the ordinary scales at command, was nearer 6 than 7. As Professor Schaeffer had only one fragment by post, while I had an abundance from many places, it may yet be found that columbic acid predominates in some of the specimens. I therefore use the name columbite or tantalite indifferently. With this explanation I proceed to give a few observations upon the occurrence of the mineral with the tin-ore of the Black Hills. There are two localities, especially, where the mineral is found in the same dike or vein as the cassiterite: 1. at the Etta mine; 2. at the Bob Ingersoll claim. At the Etta it occurs in close association with albite and feldspar in crystals from one to four or five inches broad, and from one-quarter of an inch to three inches thick. It is not in contact with or mingled with the cassiterite, and each call be

Jan 1, 1885

By Sir John Cadnan

The production from the Maidan-i-Naftun area for the year ending March, 1928, was 5,340,000 tons (40,210,200 bbl.), an increase of nearly 13 per cent. over the production for the year ending in March, 1927. The production by years since the opening of the field in 1912 is given in the following table: [1 ton = 7.53 bbl.] Year Ended MaRch Tons Year Ended March Tons 1912 (7 months)............. 43,084 1920....................... 1,354,631 1913........................ 80,800 1921....................... 1,767,070 1914........................ 273,635 1922....................... 2,310,098 1915........................ 375,977 1923....................... 2,913,908 1916........................ 449,394 1924....................... 3,583,000 1917........................ 644,074 1925....................... 4,221,000 1918........................ 897,402 1926....................... 4,470,000 1919....................... 1,081,919 1927....................... 4,735,000 1928....................... 5,340,000 The actual production represents only a small proportion of the potential production. The Masjid-i-Suleiman Field The present producing unit, the Masjid-I-Suleiman, is an anticline some 20 miles in length by 4 miles in width, including three domes as so far proved. The producing horizon is a very open, dolomitic limestone, which, while showing much variation in texture and porosity, is so connected that the lowering of pressure in one section of the field quickly affects the whole area. The topography of the field is broken, with differences of well elevations of as much as 1100 ft. The depths to the limestone vary from about 800 to about 5000 ft. The closed-in pressure of the oil wells varies from zero to 50 lb. per sq. in. and that of the gas wells is about 450 Ib. Although the static oil level may be several hundred feet below ground level, in oil wells of high elevation, all the wells flow continuously or intermittently after they are once started—the majority continuously. The gas is very high in hydrogen sulfide in gas-oil wells of low pressure.

Jan 1, 1929

By Valentin R. Garfias, C. O. Isakson

The production of oil in Mexico during 1929 was approximately 45,000,000 bbl., or 5,000,000 bbl. less than in 1928. The production of the fields near Tampico showed a decline of over 10,000,000 bbl. for both the light and heavy crudes, which was partly offset by an increase of over 5,000,000 bbl. in the production of the fields in the Isthmus of Tehuantepec. During 1929 the retrenchment policy followed by practically all the companies was continued and no material improvement should be expected until the unsatisfactory conditions that brought about this situation are remedied. A new administration has just assumed control in Mexico; it should remain in power for 6 years, and the progress of the oil industry during that time will depend primarily on the policy pursued by the new government with respect to oil development. Development During 1929, there were drilled 214 wells as compared with 371 in 1928 and 583 in 1927. The percentage of producers in 1929 was 47.2 as against 34 per cent. in 1928. The new wells did not show water as quickly as in 1928, particularly in the Cacalilao field, where the greatest number of producers was brought in, their average initial daily production being 380 bbl. The flush daily production per well in the Southern fields was 1730 bbl., while the wells in the Isthmus of Tehuantepec came in with an average of 770 bbl. Development is summarized in Table 1. In the Southern fields 63 wells were drilled in 1929, of which 23 were producers, the best being drilled in Paso Real. This development tends to show that the southern extension of Dos Bocas-Alamo fault from Alamo to San Isidro terminates at San Isidro. The two wildcat wells completed in 1929, one in Magiscatzin and the other in Xicotencatl, were failures, and at the end of the year there were eight wildcat wells drilling and material was being hauled for two more.

Jan 1, 1930