Search Documents

By A. Andreas

New Mexico retained its position in 1938 as the sixth largest oil-producing state, with a total production of 35,510,176 bbl. This was 2,875,598 bbl. less than the 1937 production of 38,485,774 bbl., or a decrease of 0.077 per cent, which was caused by the lack of pipe-line facilities and storage at the pipe-line terminals. The production for Lea County (excluding Maljamar) was 32,926,788 bbl.; for Eddy County (including Maljamar) was 2,225,411 bbl.; and for northwestern New Mexico (San Juan and McKinley Counties), 357,977 bbl. The average daily nonmarginal well allowable for Lea County on Jan. 1, 1938, was 65 bbl. At the close of the year it was 49 bbl. The average daily pipe-line runs for domestic consumption were less than the state allowables recommended by the United States Bureau of Mines. There was a demand for Artesia crude for foreign export, which if included in the daily production for New Mexico would be slightly in excess of the daily production recommended for New Mexico by the Bureau of Mines. The daily average production for the year was 97,329 barrels. There were 622 completions in the state, of which 520 were oil wells; 16 hydrocarbon gas wells; 5 carbon dioxide gas wells, and 81 dry holes. Of the dry holes 38 were in or near-by proven fields and the remainder, 43, were wildcats. Five new fields were discovered in New Mexico during 1938, three in Lea County and two in Eddy County. Southeastern New Mexico Lea County.—The Monumcnt field was the largest producing field in Lea County, with 9,440,334 bbl., and was closely followed by the Eunice field with 8,872,335 bbl. The Hobbs field was third with 5,010,414 bbl. The greatest activity in Lea County was in the Vacuum pool, with 129 completions, of which 126 were oil wells and three were dry holes. The Texas Company completed its Corbin NO. 1 in the KW 1/4 SW1/4 sec. 10, T. 18 S., R. 33 E. in August. This well was drilled to a depth of 5118 ft. in a white sand, encountering salt water. It was plugged back to 4315 ft, and pumped 43 bbl. of 36" gravity oil in 12 hr. It was approximately 6 miles southwest of the closest production in the Vacuum

Jan 1, 1939

By A. Andreas

New Mexico retained its position in 1938 as the sixth largest oil-producing state, with a total production of 35,510,176 bbl. This was 2,875,598 bbl. less than the 1937 production of 38,485,774 bbl., or a decrease of 0.077 per cent, which was caused by the lack of pipe-line facilities and storage at the pipe-line terminals. The production for Lea County (excluding Maljamar) was 32,926,788 bbl.; for Eddy County (including Maljamar) was 2,225,411 bbl.; and for northwestern New Mexico (San Juan and McKinley Counties), 357,977 bbl. The average daily nonmarginal well allowable for Lea County on Jan. 1, 1938, was 65 bbl. At the close of the year it was 49 bbl. The average daily pipe-line runs for domestic consumption were less than the state allowables recommended by the United States Bureau of Mines. There was a demand for Artesia crude for foreign export, which if included in the daily production for New Mexico would be slightly in excess of the daily production recommended for New Mexico by the Bureau of Mines. The daily average production for the year was 97,329 barrels. There were 622 completions in the state, of which 520 were oil wells; 16 hydrocarbon gas wells; 5 carbon dioxide gas wells, and 81 dry holes. Of the dry holes 38 were in or near-by proven fields and the remainder, 43, were wildcats. Five new fields were discovered in New Mexico during 1938, three in Lea County and two in Eddy County. Southeastern New Mexico Lea County.—The Monumcnt field was the largest producing field in Lea County, with 9,440,334 bbl., and was closely followed by the Eunice field with 8,872,335 bbl. The Hobbs field was third with 5,010,414 bbl. The greatest activity in Lea County was in the Vacuum pool, with 129 completions, of which 126 were oil wells and three were dry holes. The Texas Company completed its Corbin NO. 1 in the KW 1/4 SW1/4 sec. 10, T. 18 S., R. 33 E. in August. This well was drilled to a depth of 5118 ft. in a white sand, encountering salt water. It was plugged back to 4315 ft, and pumped 43 bbl. of 36" gravity oil in 12 hr. It was approximately 6 miles southwest of the closest production in the Vacuum

Jan 1, 1939

By David B. Reger

The substantial expansion of previously discovered gas pools was the principal feature of petroleum activity in West Virginia during 1940. At least one new gas pool was discovered and various other successful wildcat completions may prove to be gas-pool openers. Some slight extensions of oil pools were also made. The new productive territory, principally gas, added by these extensions was approximately 33,800 acres. ' In general, oil activity was slight because of unfavorable crude prices. Gas activity, on the contrary, increased considerably, although the price of gas did not materially change. The account of operations, as gathered from trade journals and other reporting services, shows that 709 new wells were drilled, resulting in 102 new oil wells with I055 bbl. of daily new produc-tion; 468 new gas wells with 633>g47,000 cu. it. of daily open flow; and 139 dry holes. Also, 91 old wells were drilled to deeper sands, with 143 bbl. and 44,833,000 cu. ft. of added production. On the new wells the oil average was 10.34 bbl, per well per day; and the gas average was 1,354,000 cu. ft. per well per day. On new wells the ratio of dry holes to completions was 19.61 per cent. On deeper drilling to other sands the ratio of failures was 12.I per cent. From an exploratory standpoint, one strictly new gas pool (Lorentz) was opened in Upshur County. Little forecast of its extent or reserve can now be made. The new extensions of various other previously discovered pools, however, give assurance of a new gas reserve that will equal approximately a year of gas demand. In addition to these definite supplies two widely separated Oriskany sand (L. Dev.) wildcats in Jackson County, one of which was completed late in 1940 and the other early in 194.1, may indicate two separate pools or may greatly extend known pools. In south-ern Kanawha County, also, an old Oris-kany-sand well deepened to the White Clinton sand (Sil.) showed a volume of 733,000 cu. ft. and rock pressure of 1800 Ib., giving rather clear assurance that this deep sand, in which only slight quantities of gas had previously been found, should eventually supply much new gas. On the other hand, various deep tests to the Oriskany sand in Harrison, Putnam, Randolph and Wood Counties were totally dry or gave only small volumes of gas, The principal oil wells completed, by counties, were: Calhoun, 15; Clay, Ir; Pleasants, 14; Ritchie, 15; and Roane, 7. Production for the year was estimated by the U. S. Bureau of Mines as 3,444,000 bbl., as compared to 3,684,000 bbl. in 1939. The leading counties in gas-well completions were: Boone, 36; Braxton, 17; Cabell, 25; Calhoun, 16; Clay, 22; Gilm.er, 47; Jackson, 38; Kanatvha, 77; Lincoln, 18; Putnam, 32; IGtchie, 40; and Wayne, 31, Production for the year is estimated by me as I70,000,000,000 cu. ft. as compared to I59,226,000,000 cu. ft.* in 1939. No long pipe lines were built but various gas-line extensions and cross connections,

Jan 1, 1941

By David B. Reger

The substantial expansion of previously discovered gas pools was the principal feature of petroleum activity in West Virginia during 1940. At least one new gas pool was discovered and various other successful wildcat completions may prove to be gas-pool openers. Some slight extensions of oil pools were also made. The new productive territory, principally gas, added by these extensions was approximately 33,800 acres. ' In general, oil activity was slight because of unfavorable crude prices. Gas activity, on the contrary, increased considerably, although the price of gas did not materially change. The account of operations, as gathered from trade journals and other reporting services, shows that 709 new wells were drilled, resulting in 102 new oil wells with I055 bbl. of daily new produc-tion; 468 new gas wells with 633>g47,000 cu. it. of daily open flow; and 139 dry holes. Also, 91 old wells were drilled to deeper sands, with 143 bbl. and 44,833,000 cu. ft. of added production. On the new wells the oil average was 10.34 bbl, per well per day; and the gas average was 1,354,000 cu. ft. per well per day. On new wells the ratio of dry holes to completions was 19.61 per cent. On deeper drilling to other sands the ratio of failures was 12.I per cent. From an exploratory standpoint, one strictly new gas pool (Lorentz) was opened in Upshur County. Little forecast of its extent or reserve can now be made. The new extensions of various other previously discovered pools, however, give assurance of a new gas reserve that will equal approximately a year of gas demand. In addition to these definite supplies two widely separated Oriskany sand (L. Dev.) wildcats in Jackson County, one of which was completed late in 1940 and the other early in 194.1, may indicate two separate pools or may greatly extend known pools. In south-ern Kanawha County, also, an old Oris-kany-sand well deepened to the White Clinton sand (Sil.) showed a volume of 733,000 cu. ft. and rock pressure of 1800 Ib., giving rather clear assurance that this deep sand, in which only slight quantities of gas had previously been found, should eventually supply much new gas. On the other hand, various deep tests to the Oriskany sand in Harrison, Putnam, Randolph and Wood Counties were totally dry or gave only small volumes of gas, The principal oil wells completed, by counties, were: Calhoun, 15; Clay, Ir; Pleasants, 14; Ritchie, 15; and Roane, 7. Production for the year was estimated by the U. S. Bureau of Mines as 3,444,000 bbl., as compared to 3,684,000 bbl. in 1939. The leading counties in gas-well completions were: Boone, 36; Braxton, 17; Cabell, 25; Calhoun, 16; Clay, 22; Gilm.er, 47; Jackson, 38; Kanatvha, 77; Lincoln, 18; Putnam, 32; IGtchie, 40; and Wayne, 31, Production for the year is estimated by me as I70,000,000,000 cu. ft. as compared to I59,226,000,000 cu. ft.* in 1939. No long pipe lines were built but various gas-line extensions and cross connections,

Jan 1, 1941

By B. Prof. Silliman

THE experiments detailed by Dr. Hunt,* having demonstrated the fact that the copper contained in the "clay ore" of Jones's Mine, was rendered completely soluble in the bath of ferrous chloride, used in the Hunt and Douglas process, after heating in contact with carbonaceous matter in a close vessel, I set myself to devise a form of muffle furnace adapted to the treatment of large quantities of these and similar ores by a continuous process. The result is shown in the diagrams on Plate X, reduced from the working drawings, after which this furnace was built early in 1876, at Phoenixville, by the Chemical Copper Company on their works at this place. The peculiar character of this ore determined the form, dimensions, and position, with reference to charging and discharging of these muffles. The ore arrived from the mine with from 20 to 25 per cent. of moisture, and when dried at 212° F., or more slowly at lower temperature, it falls to a light incoherent powder, with occasional lumps of undecomposed rock. In this condition it is readily mingled with coal-dust or any like reducing agent, and requires no other preparation for the muffle than the use of the shovel, to mix it well with the reducing agent. As it is a remarkably good non-conductor of heat, it was obvious that the mass, to be heated through in a reasonable time, must not be too thick, while the weight of the mass must be sustained in a way to avoid undue strain upon the walls of the muffle. These walls must be as thin as practicable, to favor the more rapid transmission of heat, and must, therefore, be so con¬structed as to admit of being stayed on the sides at frequent intervals to resist the lateral thrust of the very mobile mass of pulverulent ore, which, for obvious reasons, must be charged at the top and drawn from the bottom of each chamber. These considerations led to the form adopted, viz., two vertical muffles, standing upon very strong bridge tiles, seen in longitudinal section, on the line E, F, and in plan in Fig. 3, on the same plane. (Plate X.) The vertical section of the muffle is seen in Fig. 4, drawn in the plane G, H, of the longitudinal section, Fig. 6, which is the key to all sections. The walls of the muffles are built of the best firebrick, very care- * See paper by Dr. Hunt, page 325.

Jan 1, 1876

By C. A. Heiland

FOR the past three years, the senior writer has carried out, with inter-ruptions, a series of investigations into the characteristics of prospecting seismographs of a wide variety of construction. Early in 1932, a com-plete equipment was developed for both refraction and reflection observa-tions; its first function being, however, the application in reflection shooting. The performance of the equipment proved to be highly satis-factory in a series of field tests' which were carried out by the junior writer, whose services were loaned to the Colorado School of Mines by courtesy of the Plains Exploration Co. in Denver. The various problems that were encountered in the construction of the equipment, in its application in the field, and in the interpretation of the results, are fully treated in Publication 47 of the Department of Geophysics of the Colorado School of Mines. Its first part deals with the various problems encountered in the design of the instruments, and presents a discussion of such topics as the free and forced oscillations of damped and undamped mechanical seismographs, the action of oscil-lographic recording instruments and amplifiers, the characteristics of electromagnetic seismographs, and the requirements of damping, natural frequencies and static magnification for the pickups, amplifiers and oscillographs used in refraction and reflection seismographs. Further-more, a detailed discussion of the various methods of static and dynamic tests of seismic receivers, and a description of the reflection equipment developed at the School of Mines is presented. Unfortunately, a delay has occurred in the publication of the first part of this investigation concerning the instrument problems. There-fore, the second part, dealing with the field problems, is herewith pre-sented first.

Jan 1, 1933

By C. Chamberlain

The Telfer Project, Australia's newest, largest, and most remote gold mine treats 480 kt of ore grading 9.33 g/t derived from open pit mining operations. Coarse gold is recovered by gravity concentration with jigs and further upgraded wing a continuous strake launder table, and by amalgamation. Remaining gold is recovered in a cyanide circuit and incorporates flat bottom air agitators, counter current decantation (CCD) and stellar filters for clarification and precipitate removal. Overall recovery into a bullion averages 98%. The mill incorporates a number of design features that allow for maximum efficiency and security wing a minimum number of operation personnel.

Jan 1, 1983

By J. B. Dilworth

In estimating the investment-value of a mining-property or plant, the value of which decreases with operation, it is often necessary to know the sum which must be set aside periodically from earnings either to renew the plant at the end of its life, or to return the capital involved when the earningpower of the investment has ceased. In such cases it is manifestly incorrect simply to divide the total amount to be retired by the 'number of periods (usually years) during which the investment shall be active, as the sums periodically withdrawn have a certain interest-earning power varying with the length of time they are held and with the opportunities afforded for their investment. But though the interest may be considered to accumulate regularly year by year, yet the rules and tables for compouiid interest do not apply, owing to the addition of a fixed amount of new money to the total at the beginning of each period. Briefly stated, the problem of sinking-funds is, to find the amount of money which must be periodically set aside at a certain rate of interest, regularly compounded, to yield a certain sum in a given length of time. In most practical cases the interest is compounded and the fresh amount added at the same time—usually once a year—and on this basis the problem may be solved as follows : Let S = total amount to be retired, Let T = interest rate : R = 1 + r, Let n = life of tlie sinking-fund or the amortization-period, Let L = the sum set aside at the end of each year. Then the amouilt of the sinking-fund at the end of first year is 2, which at the end of n years will have illcreased by compound interest to IRn-l. Similarly, another amount, x, will be set aside at the end of second year, which will in turn increase

Jan 1, 1911

By AIME AIME

TEXAS not only produces millions of barrels of petroleum daily, but supplies the oil industry with an asset infinitely more valuable than liquld gold. That asset is leadership. The oil industry was built from its humble beginning a few decades ago into a potent force in world economy by human hands and human brains. One of these great leaders in the busy world of oil is Wallace Pratt, of the Humble company, who has been called to a position as director and member of the executive committee of the Standard Oil of New Jersey. So reads the Houston Post of June 3, 1937.

Jan 1, 1944

By V. W. Aubel

Among the iron-bearing ores of the world, the titaniferous iron sands of New Zealand are probably the least known to American engineers. This is not surprising in view of the fact that American ironmasters look with disfavor on any, even domestic, ores containing over 1 per cent. titanium. The possibilities of smelting titanium-bearing ores in the blast furnace are still undetermined, but the problem of their efficient reduction is becoming more important each year. There seems to be little inclination on the part of American furnace operators to tackle this problem, and they will no doubt continue to utilize the non-titanium ores at their command, leaving research and experiment to those countries not so fortunately endowed. New Zealand has, however, been intensely interested in her deposits of titanium-bearing iron sand, and during the last 50 years considerable English and New Zealand capital has been expended on this problem. The extent of the New Zealand iron-sand deposits is almost beyond measure. From Patea north to Manuka Heads, along almost the entire west coast of the North Island, these deposits exist. Wherever there is beach sand along this 300 mi. of coast line, the sand is iron bearing. It varies considerably in grade; but wherever the contour of the coast affords small bays and inlets, large dunes are found that are remarkably uniform in quality. Several of these large deposits, especially those at New Plymouth and Patea, are noted for their high iron content. The dune at New Plymouth runs between 55 and 60 per cent. of metallic iron; the panning action of the prevailing westerly winds and northwesterly currents has no doubt resulted in this concentration. Whatever the origin of this material may be, there is no doubt that deposition is going on continuously. At New Plymouth, a small artificial harbor, protected from the drifting sand by a large breakwall, has been dredged. Here sailing vessels have for years been loaded with iron sand for ballast by means of a crane and grab bucket operated from the wall of the breakwater. Thousands of tons of sand have been removed from this spot yet each succeeding storm renews the supply. The sand dune shown in Fig. 1 has been tested to a depth of 50 ft. (15 m.) without losing its

Jan 1, 1920

THE Nominating Committee appointed at the Division meeting in October and consisting of Frank A. Herald, A. W. Peake, C. R. McCollom, Joseph Jensen, H. W. Camp, C. P. Watson, F. Julius Fohs, George Otis Smith, J. B. Umpleby, J. M. Lovejoy and A. W. Ambrose, have presented the following ticket for the year 1929: Chairman, Joseph B. Umpleby; associate chairman, A. C. Rubel; secretary-treasurer, R. Van A. Mills; vice-chairman for Economics, Warren A.. Sinshein~er; vice-chairman for Engineering Education, H. C. George; vice-chairman for Engineering Research, Harry H. Hill; vice-chairman for Production, C. P. Watson;vice-chairman for Refinery Engineering, A. D. David. For Production Engineering Charles V. Millikan. is named vicechairman, with ,Charles E. Beecher, Glenn D. Robertson and W. W. Scott as associate vice-chairmen. The Executive Committee named is to consist of Joseph B. Umpleby, chairman with A. W. Ambrose, Charles E. Beecher, A. D. David, Glenn D. Robertson, H. C. George, Harry H. Hill, John M. Lovejoy, Charles V. Millikan, R. Van A. Mills, Earl Oliver, A. W. Peake, A. C. Rubel, W. W. Scott, Warren A. Sinsheimer and .C. P. Watson, members. Ballots will be mailed to members of the Division.

Jan 1, 1928

By AIME AIME

IN an address before the New York Section. A.I.M.E., Oct. 20, Alex L. ter Braake, speaking on the tin industry of the Netherlands East Indies, interjected a few remarks, at the chairman's request. on the mineral stock-piling project now before Congress in a bill sponsored by Senator Scrugham. The full text of Mr. ter Braake's paper was published in the Nov. 6 issue of the American Metal Market. Following mention of the buffer stock scheme as applied in the tin industry, Mr. ter Braake continued:

Jan 1, 1943

By AIME

BORN in 1899, in Bridgeport, Conn., E. A. Anderson grew up in a center of the nonferrous metal industry. Perhaps that had something to do with his selection of mining as a career while an undergraduate in Yale. After securing his Ph.B. in mining he worked for a year at Handy & Harman. By this time physical metallurgy had supplanted his interest in mining and he entered the Yale graduate school where he secured his M.S. degree in metallography under C. H. Mathewson. After completing his graduate work he entered the employ of The New Jersey Zinc Co. in their research division where he has remained ever since. The transition from graduate study to industry involved no disruption of technical interests. Academic research relating to the zinc-aluminum alloys, then coming into use for die-casting, was followed by extensive and productive industrial research in the perfection and commercialization of these alloys. Research on rolled zinc and rolled zinc alloys, corrosion and stress corrosion, dry cells, electroplating on zinc, and electrodeposition of zinc followed in overlapping succession as time passed.

Jan 1, 1947

By P. van Meurs

This paper describes a technique which permits visual observation of oil displacement processes througlrout the interior of a porous structure as thick as 2 in. A model having glass walls is filled with finely powdered glass. Such a model becomes completely transparent if the powdered glass pack is saturated with an oil having the same refractive index as the glass. When water or gar, with a refractive index different from that of the oil (glass) is injected, the model becomes opaque in the space occupied by the water (gar). visual observation and photography of these displacement processes are thus rendered possible. The following processes have been studied: (I) displacement of oil by water (linear drive) in a homo-geneous formation and in a stratified formation, (2) water flooding (five-spot well pattern), (3) solution gas-drive process, and (4) oil-bank formation. INTRODUCTION Most of the scaled model experiments heretofore carried out in the Koninklijke/Shell Laboratorium, Amsterdam, have been done in steel containers, in which oil-saturated sand packs represented the oil-bearing formation. In such experiments, for instance those on the displacement of oil by water, the cumulative oil production was measured as a function of the cumulative water injection. In order to interpret the measured production data, a need has for some time been felt for a means of observing visually what happens in the course of such experiments. Some information of this kind was obtained earlier by observing the water-oil distribution in various cross sections of the sand after the conclusion of the experiment.' However, the technique used did not guarantee that the fluid distribution remained undisturbed. Moreover, the procedure was somewhat elaborate and the information obtained limited. Therefore a new technique has been developed, which is described below. DESCRIPTION OF EXPERIMENTAL TECHNIQUE AND APPARATUS Glass models simulating part of an oil reservoir are filled with ground Pyrex glass of a specific grain size, representing the porous structure of the prototype. Before an experiment is started, the porous formation has to be saturated completely with an oil having exactly the same refractive index as the Pyrex glass powder. All light-scattering surfaces of the glass grains become invisible and the formation is then transparent. If the oil is displaced by another fluid (e.g. by water in a water-drive experiment, or by gas liberated from the oil in a solution gas-drive experiment) the formation becomes opaque in the region where the oil is expelled from the rock.* The back of the apparatus is painted black and illumination is from the front; therefore, in the photographs of the experiments, the oil-bearing formation appears black, whereas the water- or gas-invaded areas are white.

Jan 1, 1958

By AIME AIME

THE PAPER, "Surface Effects on Assay Beads Caused by Metals of the. Platinum Group," presented by J. L. Byers, before the Institute of. Metals Division at the February meeting of the Institute, is the subject of interesting discussion, an abstract of which follows. The original paper is available at Institute headquarters as a Preprint. Member-What assurance have you that the percentage of metals, as stated, is really an accumulation?

Jan 1, 1932

By William B. Plank

ENROLMENT data given in this report of the seventh study of the schools by the Mineral Industry Education Division reveals the critical situation in the mineral engineering schools of the United States. Complete figures for the year 1942-43 show that at that time, about one year after Pearl Harbor, the enrollment of mineral engineers was 6385 or 30 per cent less than in 199441. By October 1943, however, enrollment had dropped to 2050, as reported in the Journal of Engineering Education of January 1944. This was a further reduction of 68 per cent in one year, or 77 per cent in three years. With accelerated programs in effect during the current year, with many graduations since last October, and with the military forces taking practically all the high school graduates, the present enrollment is, of course, much lower than the 2050 above given. There are no late data on the exact situation. In Canada, the same situation exists in the mineral engineering schools, only

Jan 1, 1944

Prof. H. O. Hofman, Massachusetts Institute of Technology, Boston, Mass. (communication to the Secretary): When Mr. Stetefeldt quotes me as saying that " silver-assays are uniformly made by scorification," he has evidently not understood that I was referring solely to the practice of silver-lead smelting-works. Everybody knows that silver-mills do not employ the scorification-assay for regular work ; and it is equally certain that in very few, if any, silver-lead smelting-works will the crucible-assay be found in use for determining silver. The second part of the quotation, "as it is adapted to all kinds of ores and gives excellent results unless organic matter is present," although, of course, also intended in a restricted sense, might very well be extended to a general one. Mr. Furman, in his Manual of Practical Assaying,* says, on page 123: "We believe that the Colorado practice is preferable, as most ores will yield higher silver-results by scorification." The fact that the scorification-assay is the accepted one in Colorado is strong presumptive evidence for its accuracy, as exactness would nowhere else be more jealously demanded. Mr. Stetefeldt cites Albert Arents- as a supporter of his preference for the crucible-assay, although I had already done so in favor of scorification. Looking up again the reference, I find that I was justified in quoting him, as, while Mr. Arents advocates the crucibleassay for low-grade gold ores, not on account of the greater accuracy of its results, but because it is quicker and less expensive, he condemns it§ for the assay of silver-ores, and prefers the scorifier for rich goldores, and for coppery ores, and in general for ores containing both silver and gold. As I, like Mr. Stetefeldt, have kept no detailed

Jan 1, 1895

By W. L. Dennen, V. H. Wilson

This paper is a description of the opera-tion and results of a Humphreys Spiral Silt Cleaning Plant at the Powderly Colliery 01 The Hudson Coal Co. during the first nine months of operation and follows a preliminary description given at the .Institute cite Institute in May, 1947, in a paper titled "Preparation of Anthracite Silt for Boiler Fuel in a Humphreys Spiral Test Plant" by H. H. Otto, V. H. Wilson and W. L. Dennen. This plant is considered a full size op-erating test plant and, like all new plants, numerous minor changes in the methods of operation have been made from time to time to secure the results desired. Views of the silt preparation plant and of the screening house are given in Fig I and 2. This plant consists of 48 spirals in 8 batteries of 6 spirals each, 36 of which were to be operated as primary spirals and the remaining 12 as secondary spirals. A brief description of the plant and its operation follows. The only material cleaned at the plant during 1947 was that carried in the underflow from the Thickener which han-dles the Breaker waste water. This under-flow, amounting to approximately 2000 gpm of water and containing 12.6 pct of solids, is pumped to vibrating screens where the plus 3/16-in. material is removed. (Fig 3). This oversize material drops into a pocket from which it is trucked to the run-of-mine tipple for re-preparation.

Jan 1, 1949

By R. S. Handy

THE properties of the Patiño Mines and Enterprises Consolidated, Inc., a New York corporation, are near Llallagua in the department of Chayanta in the west central part of Bolivia, South America, about 80 miles southeast of Oruro and 250 miles southeast of La Paz, the largest city in Bolivia and its virtual capital. The properties are accessible by railroad from three points on the west coast-from Mollendo, Peru, across Lake Titicaca, from Arica by way of La Paz, and from Antofagasta, Chile. The latter route, although the longest, is recommended by the companies as affording a more gradual introduction to the high altitudes; the mine being 13,000 ft. above sea level. The company operates its own railroad from its properties at Uncia to Machacamarca on the Chile & Bolivia R. R., a distance of 60 miles. This railroad is well equipped and well operated, and its location among the mountains surrounding Uncia represents excellent engineering skill. In fact all of the railroads, although they are of only a meter gage, are remarkable for the excellence of their construction, the arrangement of their dining and sleeping cars and the precision of their operation. There is only one drawback to rail- road and hotel accommodations and that is the absence of heating facilities, which does not seem to affect the natives but keeps a tenderfoot's teeth chattering continually. The company is a consolidation of the Patiño company, owning properties at Uncia, with the Compafiia Estanfera de Llallagua, a' Chilean corporation owning contiguous properties at Llallagua. Before the consolidation these companies were deadly enemies, and there still remain at the surface plant at Uncia the fortifications and underground defences provided during the warfare between the two factions. Also, in the Azul, or "Blue" tunnel at the junction line between the two properties is a strong steel barricade still bearing marks of the bullets fired during the various armed tilts between the workmen of the two companies. The headquarters for the mining operations and the milling plant have been moved since the consolidation from the original location at Uncia to the Llallagua side of the mountain, where the Chilean company's operations were carried on. The historic old town of Uncia, with its massive stone buildings of Spanish design, is a wreck, while the Llallagua side is being rapidly built up with modern structures.

Jan 1, 1929

By Michel T. Halbouty

The area for which oil and gas developments in South Texas are reported for 1940 in this paper covers the same counties that were included in the reports for 1938 and 1939, with the addition of LaSalle County. LaSalle County is includcd in the Laredo district of South Texas, which totals seven counties for that district. The Corpus Christi district remains the same, with nine counties. The two districts together comprise what is known as the South Texas area for this report. Continued exploration along established trends and beyond proven field limits during 1940 provided South Texas with new fields and new producing levels at a rate of discovery fairly comparable with the high records set during recent years. The wells drilled in the counties within this district (including LaSalle) numbered 1656, approximately 8 per cent below the 1801 figure of last year. However, rank wildcats totaIed 336, an increase of 17.5 per cent compared to the 286 drilled in 1939. Therefore, since new field discoveries numbered 25 in 1940 against 29 in 1939, the rate of new field discoveries in 1940, based upon rank wildcats drilled, was I/I3.4 while that of 1939 was I/9.86, which shows a decrease of about 25 per cent in the rate of new fields. The rank wildcat tests in 1940 gave the following results: 18 produced oil, 4 produced distillate with gas, 3 produced. only gas, and 3r1 were dry holes (Table 5). Of the 1320 tests drilled in already proven fields or as extensions to pro+en areas (representing a decline of 12.8 per cent from last year's total of 1515 tests), 1048 produced oil or distillate, 60 produced gas and 212 were dry holes (Table 4). Of the producers, 50 found new sands or crude-in-distillate-sands in existing fields. Among the several fields subjected to extensive development were: Colorado, Jim Hogg County; East White Point, San Patricio and Nueces County; Rincon and Sun, Starr County; Glen, Webb and Zapata Counties; Wade City and Orange Grove, Jim Wells County; Stratton and South Clara Driscoll, Nueces County, and Aransas Pass, San Patricio and Aransas Counties. The development of important crude reserves on structures formerly considered primarily distillate fields has probably been the most important phase of the year's operations in South Texas. The Rincon, Stratton, Agua Dulce, Wade City, Odem and Robston fields provided the new crude sand discoveries. At some places crude production was opened by exploratory wells that found new sand horizons; in others by flank wells that found already discovered distillate sands sufficiently low to provide crude production. Rincon, Starr County, with its multiple sands, is now believed to be one of South Texas' largest crude-oil reserves. Offshore drilling showed important results during the year, including the discovery of two new submerged fields and the extension of the East White Point field into offshore Nueces County. The new marine fields are: East Flour Bluff) 76

Jan 1, 1941