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By Kenneth Cottingham

The year 1941 brought a considerable increase in drilling activity in Ohio. In 1940, the total of wells completed was 1228, whereas in 1941 it was 1561, or an increase of approximately 27 per cent. Of the 1561 wells, 333 were oil wells, 701 gas wells and 527 dry holes. The completions for the past five years are shown in Table I; the number of productive oil or gas wells for the year 1941, arranged by producing formations, are given in Table 2; the number of wells, oil, gas or dry, completed in each county in 1941, in Table 3, and wells by sands in Table 4. The production of oil increased by about 500,000 bbl. in 1941, nearly all of the increase being in Pennsylvania grade. In 1940, the total production was 3,052,000 bbl. from 25,500 wells. In 1941 the total production was 3,547,534 bbl. from 24,801 wells. The increase in production is chiefly due to the Clinton pool in Clayton township, Perry County, which is briefly men- tioned later in this review. The number of oil wells, by grades of oil, and the total quantities produced are shown in Table ;. Annual oil production for five years is listed in Table 6. The average prices paid for crude in 1941 were slightly higher than in 1940 These 1941 prices, with dates of change, are shown in Table 7. The maximum production of natural gas in Ohio was in the year 1915, when the total was just under 80 billion cu. ft. The maximum consumption occurred in the year 1916, and was approximately 169 billion cu. ft. For the past several years, Ohio has ranged from eighth to eleventh, in order of gas production for the different states, being in tenth place in 1940. In the matter of consumption, however, Ohio remains in fifth place. Preliminary figures for 1940 indicate that production of natural gas increased II per

Jan 1, 1942

By Kenneth Cottingham

The year 1941 brought a considerable increase in drilling activity in Ohio. In 1940, the total of wells completed was 1228, whereas in 1941 it was 1561, or an increase of approximately 27 per cent. Of the 1561 wells, 333 were oil wells, 701 gas wells and 527 dry holes. The completions for the past five years are shown in Table I; the number of productive oil or gas wells for the year 1941, arranged by producing formations, are given in Table 2; the number of wells, oil, gas or dry, completed in each county in 1941, in Table 3, and wells by sands in Table 4. The production of oil increased by about 500,000 bbl. in 1941, nearly all of the increase being in Pennsylvania grade. In 1940, the total production was 3,052,000 bbl. from 25,500 wells. In 1941 the total production was 3,547,534 bbl. from 24,801 wells. The increase in production is chiefly due to the Clinton pool in Clayton township, Perry County, which is briefly men- tioned later in this review. The number of oil wells, by grades of oil, and the total quantities produced are shown in Table ;. Annual oil production for five years is listed in Table 6. The average prices paid for crude in 1941 were slightly higher than in 1940 These 1941 prices, with dates of change, are shown in Table 7. The maximum production of natural gas in Ohio was in the year 1915, when the total was just under 80 billion cu. ft. The maximum consumption occurred in the year 1916, and was approximately 169 billion cu. ft. For the past several years, Ohio has ranged from eighth to eleventh, in order of gas production for the different states, being in tenth place in 1940. In the matter of consumption, however, Ohio remains in fifth place. Preliminary figures for 1940 indicate that production of natural gas increased II per

Jan 1, 1942

By C. H. Wilson, J. J. Jakosky

In recent years geophysical prospecting methods have become well established as important steps in economically initiating new mining ventures in the field of base-metal exploration, placer mining and water-supply problems. The value of these methods as applied to these problems has been greatly increased by new and improved instruments, and a greater degree of skill in laboratory and interpretative technique. Considerable success has been attained, with subsequent drilling checking the predicted depths within 1 to 5 per cent, on problems requiring information on thickness of fill material, depth to and contour of bedrock, extent and yardage of gravels to be mined, and location of hydrostatic water table. In these applications the geophysical work gives data comparable to drilling, and at a cost of about one-fiftieth that of drilling. Discussion of several surveys with accompanying illustrations showing geophysical methods applicable to both simple and complicated placer problems are contained in the paper. The electrical instruments for measuring electromagnetic field strength and surface potentials are described, and their use, coupled with that of other geophysical instruments in modern field procedure, is noted.:

Jan 1, 1934

By Garland R. Dever, Preston McGrain, George W. Ellsworth

Limestone resources for industrial, constructional, and agricultural uses occur on the surface and at minable depths in several areas along the Ohio River and its navigable tributaries in Kentucky. High calcium and high carbonate limestones suitable for use in cement and lime production, steel manufacture, environmental control measures, and other special uses are present in the High Bridge Group (Ordovician) and Warsaw and Ste. Genevieve Limestones (Mississippian). Deposits with thicknesses of 7.3 to 20.7 m,(24 to 68 feet) have been documented by the analysis of samples taken at 0.3-m (1ft) intervals. Active and potential mine and quarry sites afford access to water transporation and proximity to a number of industrial and metropolitan centers. Geologic factors affecting the distribution of deposits include the Cincinnati arch, regional dip into the Appalachian and Eastern Interior basins, complex faulting in and near the western Kentucky fluorspar mining district, and late Paleozoic erosional unconformities in northeastern Kentucky.

Jan 1, 1979

The separate outputs of Burma and India in 1937 were 274,664,365 gal. valued at £4,474,147 and 75,657,857 gal. valued at £1,030,591, respectively. The corresponding figures for the year 1938 were 263,823,-265 gal. valued at £3,766,810 and 87,082,371 gal. valued at £1,234,563, respectively, which is a slight increase in total quantities but a fall in value for the combined outputs of Burma and India. The appreciable increase from India in 1938 is due to an increase of over 11 million gallons from Attock and a little from Digboi, while the decrease from Burma is due to a fall of nearly 9 million gallons from Yenangyaung, over 3 million gallons from Yenangyat (and Lanywa) and half a million gallons from Minbu (Table 1). The 'amount' of gasoline produced from natural gas during the year 1938 was 10,587,291 gal. in Burma and 496,163 gal. in the Punjab.

Jan 1, 1940

The separate outputs of Burma and India in 1937 were 274,664,365 gal. valued at £4,474,147 and 75,657,857 gal. valued at £1,030,591, respectively. The corresponding figures for the year 1938 were 263,823,-265 gal. valued at £3,766,810 and 87,082,371 gal. valued at £1,234,563, respectively, which is a slight increase in total quantities but a fall in value for the combined outputs of Burma and India. The appreciable increase from India in 1938 is due to an increase of over 11 million gallons from Attock and a little from Digboi, while the decrease from Burma is due to a fall of nearly 9 million gallons from Yenangyaung, over 3 million gallons from Yenangyat (and Lanywa) and half a million gallons from Minbu (Table 1). The 'amount' of gasoline produced from natural gas during the year 1938 was 10,587,291 gal. in Burma and 496,163 gal. in the Punjab.

Jan 1, 1940

By C. G. Dunn

THE present note, which was given in the form of a Research in Progress item,' traces the origin of secondary recrystallization grains produced on annealing a cold rolled bicrystal specimen. The investigation began with the realization that a recently acquired conception for the origin of secondary grains produced on annealing cold rolled single-crystal specimens might require modifications for the case of polycrystalline materials. The stated conception2,3 begins with several conditions to be met by primary recrystallization: 1—a primary re-crystallization structure to consist of many small primaries and relatively few large primaries (diam- eters two or three times the average); 2—a primary recrystallization texture to consist of one strong preferred orientation or component and one or more weak components; and 3—a primary recrystalliza-tion structure-texture combination with some of the large primaries belonging to the weak components of the texture. When these conditions occur, some of the large primaries from the weak components of the texture

Jan 1, 1955

By Max W. Ball

An intelligent discussion of the oil situation and its needs, whether from the standpoint of the prospector, the operator, the engineer, or the public administrative officer, must be founded upon a knowledge of the law under which oil lands are obtained. A consideration of new legislation must be prefaced by an understanding of the present law and its results. This paper undertakes to present no new remedy for the ills of the present situation, no new solution of the problems the oil business is facing. It attempts merely to summarize the present law, its provisions, its origin, its development, and its effects. The discussion does not pretend to be exhaustive from a legal standpoint. It aims to avoid legal intricacies which tend to. confuse rather than clarify. It seeks but to present the essentials of the existing situation. The title to government lands known to contain valuable deposits of petroleum may be acquired only under the terms of the placer law as embodied in Section 2329 et seq. of the Revised Statutes. As a preliminary to considering the desirability of this situation it is profitable to examine into its origin. Origin of the Law Congress has left no room for doubt as to the legal applicability of the placer law to oil lands. The Act of Feb.11, 1897(29 Stat., 526), provides: "that any person authorized to enter lands under the mining laws of the United States may enter and obtain patent to land containing petroleum or other mineral oils, and chiefly valuable therefor, under the provisions of the laws relating to placer mineral claims.' . The immediate cause for the passage of this Act was stated in a brief report in the, House of Representatives (there was no debate in the Senate) to be a decision of the Department rendered Aug. 27, 1896 (Union Oil Co., 23 L. D., 223), directing the cancellation of an oil placer entry on the ground that land containing petroleum cannot be located and entered as a placer mine. The report of the Public Lands Committee of the House contains the following interesting statements Congressional Record, vol. xxix, p. 1409):

Jan 1, 1915

THIS issue is about Chuquicamata and the new sulphide plant. Chuquicamata is moving into a new cycle of productivity; she has begun to give up the sulphide copper which lies deep-seated beneath the oxide ore zones in large but yet unknown quantity. After forty years of production, Chuqui may be likened to a strapping youngster, with adolescence and maturity still ahead. Mining operations are being projected-not for decades -but for generations. Although there are still many years of open-pit mining ahead, planning of future underground mining has been started. The bottom of the orebody is still unknown, but enough work has been done to show that Chuqui is one of the largest known copper orebodies in the world. Until recently, only the oxide ores have been mined and these have been treated at the rate of 50,000 to 60,000 tons per day by leaching. Construction of the sulphide plant was timed to coincide with reduction in production of oxide ores. The new sulphide concentrator and smelter, designed in keeping with the magnitude of the orebody, will be brought on the production line at the rate of 30,000 tons per day. The capacity of the plant now planned can be expanded to treat 60,000 tons of sulphide ore. Little wonder that Chuqui is a name legendary in the remotest mining circles. But to those who have known her more intimately, and there is hardly a mining camp without a Chuqui graduate, she means much more. She is an orebody that has made engineers. Reposing at 10,000 ft on the western flank of the Andes in the arid northern reaches of Chile, water is scarce, common fuels absent, and volcanoes and earthquakes add drama and hazard. It is these natural difficulties which have created the fascination and challenge which have caused many engineers to devote their lives to unlocking this treasure house of nature.

Jan 1, 1952

By T. B. Brooks

THE iron ores of the Marquette region are mostly extracted in open excavations ; hence the process is more properly quarrying. Several attempts at underground work have been made, which have not, on the whole, been successful. The Edwards mine has been almost entirely wrought by candle-light. The slate ore pit, No. 1, of the New England mine, is now worked in the same way, as is also the Pioneer furnace pit of the Jackson mine. The Champion mine was opened systematically for underground work, with two levels, 60 feet apart, and three shafts at distances apart along the bed. of 200 feet; but this idea has been practically abandoned, the greater part of the ore in that mine being now taken out in open pits. Several other mines have occasionally worked underground stopes, but only temporarily; if such stopes could not be opened out to day-light, they have usually been abandoned. In brief, it may be said that no considerable amount of ore has as yet (1870).been extracted underground in the region, and of that so mined very little has been taken out at a profit; and I may add that it seems to be the belief of the most experienced mining men that this state of things will hold for some time to come for reasons which will appear. Nearly the same remarks may be applied to the mines of the Iron Mountain region, Missouri, the ores of which are very similar in character to those of Marquette. Some of the New York and New Jersey magnetic deposits are wrought open, but this is the exception, underground mining there being the rule. The following brief sketch of the geological structure of the Marquette deposits will indicate some advantages of the method of mining employed. The iron-bearing (Huronian) series of rocks, are stratified beds, the principal ore formation being overlaid by a quartzite, and underlaid by a diorite, or greenstone. This ore formation is made up, first, of pure ore ; second, of a mixed ore" (i. e., banded * A second part of this paper was read before the American Society of Civil Engineers. Both papers are embraced in Chapter IX, Part I, Vol. II, Geological Survey of Michigan.

Jan 1, 1873

By N. R. Tipman, G. E. Agar, L. Paré

The flotation chemistry of the commercial INCO matte separation process was investigated. The slow cooling of Bessemer converter matte forms discrete phases of Cu2S and Ni3S2 and a Cu-Ni alloy. After magnetically removing the alloy, the Cu2S and Ni3S2 are separated by flotation at pH 12.4 (saturated lime) using diphenyl guanidine (DPG) as both collector and frother. DPG has been used exclusively in this flotation process because of its unusual selectivity for copper minerals. The surface product resulting from chemisorption of DPG onto theCu2S was identified as the double salt CU(DPG)2SO4.CU(DPG)2(OH)2. The adsorption followed Langmuir behaviour up to a monolayer coverage. In the absence of DPG, the rapid adsorption of oxygen by Cu2S in flotation pulps was observed. The surface product was identified as the insoluble basic copper sulfate CuS04.3Cu(0H)2 with the production of sulfate ion. In the presence of DPG, the oxidation reaction appears to be suppressed. The frothing properties of DPG and commercial frothers were compared. DPG is not a powerful frother. Batch flotation tests confirmed that DPG is a highly selective collector when compared to most sulfhydryl collectors.

Jan 1, 1976

By AIME

PROBABLY no greater world traveler has ever been Chairman of one of the Institute's Divisions than Henry Frederick Hebley. To begin with, he was born almost as far away as possible-in Christchurch, New Zealand, Dec. 15, 1893. There he grew up, studying mechanical engineering at the local Seddon Memorial Technical College. Then he went over to Sydney, Australia, for a bit of work before sailing for the U.S.A. in 1915. After a few months as draftsman in a San Francisco office he moved over to Clarkdale, Ariz., in the engineering department of the United Verde copper smelter, which had just gone into operation. But the war was on, and Henry thought he belonged in France with the Canadian Engineers, the United States still remaining aloof from the conflict, and that was the last the copper industry saw of him. After almost two years in France he was wounded, convalesced in England and Canada, and then went back to his native New Zealand to design concrete factory buildings. But soon the United States called again, and this time he landed in Salt Lake City with the Oregon Short Line R.R. Co. Then to Chicago in 1920. where he really got into the coal industry for good, working for the Allen K Garcia Co. on the design and operation of coal mines, beneficiation plants, and combustion equipment; and joining the Institute.

Jan 1, 1946

By H. J. Wasson

At the close of 1927 Venezuela was producing at the rate of 205,000 bbl, per day, making it the third country in the world in point of present daily production. For the year, the total was close to 64,000,000 bbl., representing an increase of about 70 per cent. over the 37,000,000 bbl. in round numbers produced in 1926. All of the 1927 production canie from fields opened up before the beginning of the year. While no new fields were added to the list of shippers, the past 12 months' wildcatting yielded a fair quota of new discoveries which, in the light of prcsent results, may be considered likely sources of production in due time. Altogether three such promising finds were made Of first importance, at least for the immediate future, is the completion by the Lago Petroleum Corpn. of the San Matins well, 4 miles north of the present edge of the Lagunillas field. Although rated as only a 125. bbl. well, at 3217 ft., it indicates a probable extension of the field over the intervening 4 miles between the two. The two other wildcat discoveries of importance were the Los Manueles well in the District of Colon, which has in all probability opened up a new field about 7 miles north of the present Tarra oprations; and the Honibre Pintado well of the Standard Oil Co. of Venezuela,. in the State of Falcon, which is considered to be a promising clc~vc~lop~ncnt. Neither of these last mentioned two discoveries will apprcciably affect production during 1928, as the Manueles area must await the carrying out of a general plan for the exploitation of the District of Colon, a problem requiring time. The Hombre Pintado area is being tested further, but doubtless several wells will be put down before. anything definite will be done towards making the pipe line. arrangements that rnust necessarily precede the commercial exploitation of the field. The San Matias Well The San Matias well is a highly significant dcvelopment,. It is located along the trend of the La Rosa-Ilagunillas producing formations, and when drilling started, production in the Lagunillas field was 4 miles

Jan 1, 1928

By V. Jares

DESPITE the fact that a combination of metals-aluminum-zinc-tin, and sometimes aluminum-zinc-cadmium-is extensively used for aluminum solders, as well as for die-castings, the constitution of these alloys has not yet been made clear. I. BINARY SYSTEMS The system aluminum-zinc is the basis of the ternary alloys under consideration. Their composition was made sufficiently clear by the investigations of Rosenhain and Archbutt,1 Bauer and Vogel,2 Sander and Meissner,3 Hanson and Gayler4 and Isihara.5 Only the temperature of decomposition of the crystals 0 seems still to be doubtful, whether it is considered as a compound of Al2Zn3 (according to Bauer and Vogel) or as an intermediate phase of variant composition (according to Hanson and Gayler). This temperature is given by most of the authors as in the neighborhood of 256° C., only Isihara giving 280° C. As its accurate determination is of special importance in the study of the ternary alloys under consideration it was experimentally controlled in the following manner: An alloy corresponding in composition to the formula Al2Zn3 was made, in which the temperature effect was found to be the greatest. This was drilled and a silver-constantan thermoelement inserted into the cavity so as to be in direct contact with the alloy. The whole was then very slowly heated and the heating and cooling curves determined. The transition temperature from the heating curve was found to be 281° C., whereas from the cooling curve it was 252° C.

Jan 1, 1927

By A. S. Appleton, M. B. Bever, G. E. Dieter

A gold-silver alloy was deformed by explosive loading at shock pressures up to 510 kbars. The stored energy and hardness increased over the whole range of pressures; the largest rates of increase were observed between 120 and 150 kbars. In this range, markings rkavacteristic of defornation twins first appeared; higher pressures produced markings in all grains. These effects are compared with those of conventional deformation processes and are discussed in relation to probable structural changes. In recent years, increasing efforts have been devoted to the investigation of the effects produced in metals by the passage of high-intensity shock waves of explosive origin. By properly utilizing the energy released by the detonation of a high explosive, it is possible to generate pressure pulses of the order of 500 kbars and higher. (One kbar equals l0 9 dynes per sq cm or approximately 1000 atm.) The passage of a shock wave through a metal occurs at pressures which are very much greater than the yield strength. As the shock front passes a point in the metal, the pressure rises almost instantaneously, and continues to act at the point for a few microseconds. Thus, metals subjected to explosive shock loading experience a nearly instantaneous increase in pressure, and a subsequent release of pressure, which is almost as rapid. Under these conditions mechanical twinning and shear transformations occur readily. smith1 has investigated the metallurgical changes in copper and iron resulting from exposure to explosive shock waves. He found an appreciable increase in hardness in both metals. In copper, a hardness greater than that resulting from 95 pct reduction in thickness by rolling was obtained, yet in the explosive deformation, the thickness of the specimen decreased only a few percent. After explosive loading, the micro-structure of copper showed markings characteristic of mechanical twins. The amount of stored energy resulting from explosive loading is of interest. Measurements of the stored energy of cold work as a function of strain, temperature, strain rate, and composition have been made with gold-silyer alloys deforyed by rolling, orthogonal cutting,3 drilling,4 filing, wire drawing, and torsion. The investigation reported here was also carried out with a gold-silver alloy and its results can be compared with those for the deformation of this alloy by more conventional methods. EXPERIMENTAL PROCEDURES An alloy containing 82.6 wt pct Au and 17.4 pct Ag was purchased in several batches from Handy and Harman Co., New York, as annealed rod 1/4 in. dim. The rod was cold-rolled to a sheet approximately

Jan 1, 1962

By John Guillermo Bartram

The oil industry continued relatively quiet in Wyoming in 1935, although production increased about 8 per cent over the previous year; 55 oil wells were completed in 1935, compared to 34 in 1934, and at the end of the year 44 wells were drilling, 33 in proven fields and 11 in wildcat locations. The total drilling a year ago was only 30. In the year 1935 Wyoming produced a total of 13,451,000 bbl. of oil, a gain of 912,000 bbl. over the 1934 figure of 12,539,000 bbl. Approxi-mately two-thirds of the increase, or 630,000 bbl., was from black oil fields and one-third, or 285,000 bbl., from light oil pools. Salt Creek, with production of 6,357,000 bbl., is still many times the largest field in Wyoming but in 1935 it made less than 50 per cent of the state's total, after producing more than all other fields in the state for 24 years; however, its decline was only 3.8 per cent from the previous year. Oregon Basin, a black oil field, held second place again with production of 1,163,-000 bbl., a good increase over 1934. Grass Creek, with increases in both its light and black oil, jumped into third place; and Lance Creek, with its new Sundance light oil production, was in fourth place in the amount of production. Frannie, which was in third place in 1934, dropped far back on the list because of lack of market. Byron and Garland, two other black oil fields in the Big Horn Basin, increased considerably. Big Muddy, a prominent light-oil field, was down with a natural decline; and Elk Basin, also light oil, produced less because of market conditions. During 1934 only three gas wells were drilled in Wyoming and 29 dry holes, 13 in proven fields and 16 at wildcat locations. Of the latter, 5 were on wildcat structures of considerable interest. Of the 55 wells completed during the year, 53 were in proven fields and of these 17 were small ones in the shallow Osage field and 10 were light-oil wells good for 1500 to 3000 bbl. each in the Lance Creek field. Discoveries Two of the oil wells were discoveries at Medicine Bow and Sheep Creek. Medicine Bow is a very large anticline with more than 3500 ft. of closure and is located in Carbon County in the south-central part of the state. In 1923 it showed some oil in the Upper Cretaceous Frontier

Jan 1, 1936

By John Guillermo Bartram

The oil industry continued relatively quiet in Wyoming in 1935, although production increased about 8 per cent over the previous year; 55 oil wells were completed in 1935, compared to 34 in 1934, and at the end of the year 44 wells were drilling, 33 in proven fields and 11 in wildcat locations. The total drilling a year ago was only 30. In the year 1935 Wyoming produced a total of 13,451,000 bbl. of oil, a gain of 912,000 bbl. over the 1934 figure of 12,539,000 bbl. Approxi-mately two-thirds of the increase, or 630,000 bbl., was from black oil fields and one-third, or 285,000 bbl., from light oil pools. Salt Creek, with production of 6,357,000 bbl., is still many times the largest field in Wyoming but in 1935 it made less than 50 per cent of the state's total, after producing more than all other fields in the state for 24 years; however, its decline was only 3.8 per cent from the previous year. Oregon Basin, a black oil field, held second place again with production of 1,163,-000 bbl., a good increase over 1934. Grass Creek, with increases in both its light and black oil, jumped into third place; and Lance Creek, with its new Sundance light oil production, was in fourth place in the amount of production. Frannie, which was in third place in 1934, dropped far back on the list because of lack of market. Byron and Garland, two other black oil fields in the Big Horn Basin, increased considerably. Big Muddy, a prominent light-oil field, was down with a natural decline; and Elk Basin, also light oil, produced less because of market conditions. During 1934 only three gas wells were drilled in Wyoming and 29 dry holes, 13 in proven fields and 16 at wildcat locations. Of the latter, 5 were on wildcat structures of considerable interest. Of the 55 wells completed during the year, 53 were in proven fields and of these 17 were small ones in the shallow Osage field and 10 were light-oil wells good for 1500 to 3000 bbl. each in the Lance Creek field. Discoveries Two of the oil wells were discoveries at Medicine Bow and Sheep Creek. Medicine Bow is a very large anticline with more than 3500 ft. of closure and is located in Carbon County in the south-central part of the state. In 1923 it showed some oil in the Upper Cretaceous Frontier

Jan 1, 1936

Discussion of the paper of HOWARD N. EAVENSON, presented at the New York meeting, February, 1915, and printed in Bulletin No. 98, February, 1915, pp. 413 to 430. WILLIAM H. GRADY, Bluefield, W. Va.-Mr. Eavenson gave a comparison between accidents in the State of West Virginia and in the Pocahontas field. The figures quoted are, I presume, taken from the reports of the State Mine Inspector. There are no statistics available, in readily accessible form, giving a comparison between the Pocahontas field and the mines of the United States Coal & Coke Co. which are a part of the field. It occurs to me that the paper would be more complete with these data and I will say that the mines of the Pocahontas field produced during the year 1913 about 15,000,000 tons, about 3,000,000 tons of which was produced by the United States Coal &Coke Co. This gives an indication of the extent of its operations. The Pocahontas field lies largely in the counties of McDowell, Mercer, and Wyoming in West Virginia, and Tazewell in Virginia.: Without consulting maps, I should say that all of the acreage under operation at present by this company lies wholly in McDowell County and that the average conditions off roof top and bottom in its mines are the average of the county, but that the worst conditions in some of these mines are the worst to be found in the county. The average conditions in Tazewell County are about the same as in McDowell County, except that the average thickness of the seam is much greater. The average conditions of top and roof and bottom are better in Mercer and Wyoming counties than in the mines of the United States Coal &. Coke Co.; the worst conditions in these counties are not so bad as in McDowell and Tazewell counties and the best are better than those encountered in McDowell and Tazewell counties; also the thickness of seam is less in Mercer and Wyoming counties. THOMAS W. DAWSON, Scottdale, Pa. (communication to the Secretary*).-The H. C. Frick Coke Co., the mines of which are in Fayette and Westmoreland counties, Pennsylvania, in the Connellsville coke region, has been pursuing a safety campaign for a number of years and a short resume .of its practices will be of interest in connection with Mr. Eavenson's paper.

Jan 5, 1915

. E. P. MATHEWSON, New York, N. Y.-I would like to call attention to the excellent plan for protecting the lining of the tanks from rough handling by the excavator. Many engineers, when considering mechanical excavators for lead-lined tanks, have been afraid that the machinery might get out' of order and rip out the lining. This difficulty seems to have been entirely overcome in this installation, and those who have been responsible for its success deserve a great deal of credit. A. F. CASE,* Cleveland, Ohio. (written discussion t).-The application of the automatic unloader to the copper leaching process at Ajo was a very radical departure from the common use of this machine, inasmuch as the only previous use of this device has been in connection with the unloading of coal and ore from vessels on the Great Lakes. There are many phases in connection with the unloading of ore from lake vessels that are not presented in the extraction of ore tailings from leaching vats. For instance, in unloading from boats, it is necessary to provide means to reach under the hatches to parts of the cargo hold which do not lie directly under the hatches, and to work in inaccessible places that do not exist in a leaching vat. These necessities require complications that could be very easily dispensed with in this new application. On this account the unloader, is applied to the New Cornelia, plant, represents what is probably the simplest development of the machine that has ever been produced, and, manifestly, in its simplest form it could he expected to show results corresponding to its performances when installed with all of its complications. One of the requirements of vessel unloading is extreme vertical travel, when the bucket is required to reach the bottom of the, cargo hold, often 12 or 13 ft. below water-level, and discharge into a receptacle 30 ft. above-the water. This was materially simplified at Ajo for the reason that the vertical travel was never more than 20 ft. This condition immediately resulted in the possibility of shortening the walking beam which carries the bucket leg, and, in fact, in entirely reducing the size of all the working, parts of the trolley, walking beam, and bucket leg, as far as reaches were concerned.

Jan 11, 1918

By James A. Barr, R. B. Burt, I. S. Tillotson

DISCUSSION Howard Howie (Knoxville, Term.)—The authors are to be congratulated on the presentation of a paper containing so much valuable information on the pipeline transportation of phosphate, as there is very little literature on the subject. The writer is especially interested in the paper, as he conceived the arrangement of the Akin and Godwin plants and was in charge of the design work and the engineering incident to their construction. The Akin and other phosphate deposits in the Tennessee phosphate area lie on beds of limestone that are very irregular. The limestone beds, after the phosphate matrix has been removed, are similar in appearance to land severely eroded by the action of water and denuded of top soil. Depressions in the limestone, called cutters, are irregular in depth with vertical or overhanging walls, having the general appearance of cracks in dried clay. They change abruptly in direction, width, and depth, and vary on the Akin tract from 1 to 25 ft in depth and from 1 to 50 ft in width. Pinnacles of limestone commonly occur in the cutters which appear, when exposed, like small clifflike islands in a river. Limestone floats also occur. The phosphate matrix fills the cutters and covers the uncuttered areas, the thickness of the cover varying continually and sometimes rather abruptly. It occurs generally as stratifications of phosphate rock and clay of varying thickness. The phosphate rock in the matrix varies in hardness and in percents of silica, lime, iron oxides, and fluorine, and the clay varies in toughness. In some places the deposit consists of narrow strata of rock almost devoid of clay streaks. In other nearby locations the clay will predominate. When it is excavated, the phosphate rock breaks into thin irregular lumps, locally known as plate rock. Limestone lumps are also excavated with the matrix. Akin plate rock is generally much softer than that occurring in other deposits in the area. Because of the above described physical and chemical variations of the excavated material, the resultant slurry varies in size distribution, specific gravity, and percent of slimes. When the rock is soft or when there is an increase of clay, the slime fraction is greatly increased as it passes through pumps and pipelines, resulting in reduced pipe friction. It is obvious that the longer the pipeline the greater the reduction of coarse fractions into fines, causing a decrease in pipe friction that cannot be accurately evaluated. The matrix is mined with a dragline that drops it into a hopper with a grid composed of 9-in. parallel bar spacings located above the hammer mill. The matrix on, and passing through the grid, is subject to the action of powerful sprays which wash it down to the hammer mill, together with any limestone lumps that are not removed before passing through the grid. The hammer mill reduces the feed to lumps of plate rock and clay, most of which will pass through the 8-in. pump suction. The mixture discharges into a pool containing the pump suction pipe. Water from a hydraulic nozzle moves the mixture to the pump suction intake. The pump, driven by a variable speed motor, is the same size as the pumps mentioned on p. 279. Provision is made to remove any lumps that lodge in a bend in the suction pipe in a manner similar to that used in the Florida phosphate fields. The hammer mill and pump units are mounted on wide steel skids so that they can be moved as the mining operation progresses. The discharge from the pump flows through an abrasion-resistant spiral welded steel pipe 8 1/4 in. actual inside diam, 8 in. nominal diam, for a maximum distance of 2200 ft, which is the limiting pumping distance for one pump. This pipeline, referred to hereafter as pipeline A, discharges into a ball mill without balls, which in turn discharges into a rotary screen attached to it that separates the slurried matrix into 11/4-in. oversize and undersize fractions. The oversize is returned to the mill for further reduction; the undersize is pumped to a Dorrco washer and then flows into a hydroseparator 160 ft in diam. In spite of the size reduction in the hammer mill and the blunging and washing of the slurry in its passage through the pump, pipeline, mill, and washer, the discharge to the hydroseparator frequently contains mud balls almost perfectly spherical. Sometimes the discharge from the 16,000-ft pipeline at Godwin contains mud balls the size of bird shot and smaller. This pipeline will be referred to subsequently as line B. Liquid caustic is added to the slurry at the Akin plant before its passage through the hydro-separator, which decreases the size of particles in the overflow by dispersion. In passing through pumps 1, 2, and 3 and pipeline B, the slime fraction in the underflow is increased by abrasion and blunging and also by continuing dispersive action of the caustic. The matrix for use in the experimental tests referred to on p. 279 was obtained from three small surface openings on the Akin tract that were made previous to the purchase of the tract by the Authority. Matrix used in the 2 and 4-in. experimental pipeline tests was taken from the three openings and proportioned to obtain a sufficient quantity that would be fairly representative of the average in the Akin deposits. Prospecting samples of matrix had been obtained from drill holes which showed no small variation in physical and chemical properties. Some of the physical variation is evident from the size distribution of solids in samples taken during the tests covering line B flows so thoroughly made by the Authority under the direction of Mr. Burt, see Table V, p. 280. Hydraulic gradients for a pipe of 8-in. diam were derived from the 2 and 4-in. pipeline tests using the so-called representative matrix as above described, and plotted on the profile of pipeline B. Gradients of other materials in slurry form passing through pipelines that bore some similiarity to the Akin matrix slurry were also plotted. After a study had been made of the hydraulic gradients plotted on the profile and the varying slurry flow that would probably occur during actual operation, three pumps were ordered, referred to as No. 1, 2, and 3 on p. 279. No. 1 and 2 pumps were installed and the third kept in reserve should the operation of 1 and 2 pumps prove satisfactory, since installation of the third pump would require an attendant, as well as the laying of 5400 ft of pipe to supply it with seal-water from the Akin plant. Subsequently, it was found desirable to install the third pump to maintain capacity when the slime fraction was low and the coarse fractions were large. Reference to Fig. 6 will show that the flow in B line goes upgrade in three locations. At the outlet at Godwin, the slurry flows between two 45" bends for an approximate distance of 18 ft to rise above the ground a sufficient height to discharge into a launder feeding the first classifier. This condition requires extra energy, which is taken care of by keeping the hydraulic gradient a sufficient distance above the high points. Although there are rather heavy upgrades in the line, the choking condition that might occur at the

Jan 1, 1953