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By Donovan J. Benton

Photogrammetric methods are advancing rapidly and show considerable promise as a ground control research tool. The ability to quickly capture three-dimensional geometry, especially changes in geometry, in underground and laboratory settings is a significant advance from point distance measurements. Photogrammetry is being applied in both of these settings as part of the NIOSH ground control research. This paper describes these applications and the equipment and software being employed. It also describes tests conducted to quantify the accuracy of these systems. Accuracy varied with system specifics and procedures. A factory-calibrated camera produced results within 1/32 of an inch, plus 0.04%. A user-calibrated camera was found to be less accurate, at 1/20 of an inch, plus 0.24%. These calibrations demonstrate that photo grammetry can produce research quality measurements in laboratory and mine settings.

Jan 1, 2014

By C. Mawdsley

The Tata Steel mill at Skinningrove in the North East of England produces top hat sections for mineshaft guides in sizes 102 and 150 mm. The top hat section is the technically preferred shaft guide choice for modern deep mine shafts. This paper explores the relative service performance of top hat and square hollow section guides in service. Comparative corrosion performance is reviewed and the paper describes work commissioned by Tata Steel (as Corus) undertaken by Aker Kvaerner Engineering to evaluate relative winding speeds, relative loads and fatigue life in service. The experience of supply to UK Potash mining is discussed and the future view of high capacity hoisting and larger section size market need and availability is assessed.

Aug 1, 2013

By C. S. Ha, H. S. Choi, D. Y. Shin

POSCO installed a new 100 ton oxygen bottom-blown converter in 2013 for the development of new steelmaking process named as PS-BOP which is reading POSCO-Saarstahl Basic Oxygen Process. This process was developed by the collaboration research between POSCO and Saarstahl AG in Germany that is based on substantial increase of CO post combustion in a converter by blowing hot air from the top of converter. The collaboration research has been finished successfully in November 2013 with 17% decrease in hot metal ratio (HMR) when hot air was blown from the top of the oxygen bottom-blown converter. After the collaboration research the converter has been tried to be operated as oxygen top and bottom-blown converter to reduce bottom wear and to decrease production cost with increased use of low cost Fe source by the help of increased CO post combustion. The presentation includes experience on the start up of oxygen bottom-blown converter, HMR reduction trials with hot air top blowing and transition from oxygen bottom-blown to top and bottom-blown converter operation.

Jan 1, 2015

By Robert J. Anderso

Few elements have received more attention and developed greater interest in the last ten years than titanium. The substantially pure metal has been din...ie. cult to isolate, and so far has been little employed oommercially, but the use af alloys and chemical compounds of titanium has increased markedly in recent years. The earlier attempts at preparing pure titanium resulted in various impure forme which, from their metallic appearance, were always mistaken for the metal. Hunter in 1910 isolated pure titanium by the reduction of titanium tetrachloride with sodium. This brief statement is issued by the Bureau of Mines in response to numerous inquiries which have been received concerning titanium. More complete in. formation on the metal may be had by consulting the referenpes appended. The Literature is voluminous and only the more important references are Riven. It has been drawn upon freely in preparing this report; also information was supplied by M. g. Hunter, Arthur Braid, M 1. Schmid, C. M. Johnson, N. B. Hoffman, and de Courny Browne. The pioneer investigator in titanium is A. IL Rossi.

Oct 1, 1922

By J. N. Hilton, D. Moffett, E. Barnes

"A recent pilot-plant program carried out at Rio Algom's Quirke uranium mine at Elliot Lake, Ontario is described. The goal of the research was the production of tailings basin effluents which were low in total radium-226. The process tested involved precipitation of radium with barium chloride and sedimentation in plastic-lined settling ponds. Adjustment of the tailings basin overflow from its normal value of pH 9.5 by addition of sulphuric acid to about pH 7.5 was found to give approximately a five-fold improvement in total radium-226 removal. A five-month demonstration test resulted in an effluent with a mean total radium-226 activity of44 pCi/L after 2.5 days settling time and 29 pCi/L after 5 days. The results from the demonstration program are used to propose a schedule of achievable total radium-226 activities where precipitation and sedimentation are employed. The maximum suggested values for 5 days nominal settling time are: 30 pCi/L in an annual mean, 45 pCi/L in a monthly mean. 60pCiIL in a weekly mean and 80 pCi/L in any single grab sample.IntroductionRadium-226 has been removed from effluents at the Elliot Lake uranium mines since the introduction of the first barium chloride treatment system in 1965. Current practice, which has changed little over the years, consists of radium-barium sulphate precipitation by the addition of a low do se of barium chloride to the clear overflow from the tailings basin(l·2l. Provision is made for the precipitate to settle in large natural or constructed ponds and lagoons. The residence time in these ponds, which depends on the site, ranges from 3 to 35 days, with varying degrees of efficiency being achieved."

Jan 1, 1981

By G Love, S Maher

In Victoria’s onshore Gippsland Basin, geology is driving brown coal developments, and geologists are key decision-makers. Prompted by volatile energy prices and the likelihood of a carbon constrained future, significant work has been carried out on the next generation of technologies to be applied to this giant resource. These include new-generation gasification technologies, coal conversion processes yielding products as diverse as diesel and fertiliser, drying technologies producing thermal and metallurgical coals and in situ conversion processes. However, coals aren’t coals, and brown coal available for new projects will have different quality parameters and mining economics from that currently mined.New projects are likely to be developed on coals with moisture contents averaging 60 per cent and corresponding low energy values. Whilst ash values will be low, averaging just 5 per cent (dry basis), this will at times approach 10 per cent, which is a level that would challenge the installed-generation technologies. Sulfur values will average 0.4 per cent (dry basis), but at times exceed 0.6 per cent, requiring technologies that address the potential for sulfur dioxide emissions. Whilst localised high levels of the fluxes iron (>1 per cent dry basis) and sodium (>0.3 per cent dry basis) would increase fouling of installed technologies, they may be suitable for selected next-generation technologies.Project viability for this next generation of technologies will be strongly influenced by mining cost, and geologists are playing a role in identifying higher-value coal. At its simplest, this is being achieved for open cut mines through regional, vertical strip ratio assessments, which are considered a first-order proxy for mining cost. Follow up assessments are incorporating mining and processing cost, coal quality penalties and product revenues. At a regional scale, it is informing the likely location and relative timing of future mine developments, as well as thinking around rehabilitation strategies, infrastructure and land-use planning.For deeper coal, factors like macro permeability, the ability to isolate seams from aquifers, groundwater chemistry, pressure temperature conditions, connection with groundwater recharge and in situ biota are being used as vectors to in situ coal conversion opportunities.Matching coal to the next generation of technologies has benefited from regional-scale geological studies of coal quality and mining economics, and has benefited from early engagement between geologists, technology developers and project proponents.CITATION:Maher, S and Love, G, 2014. Matching brown coal to the next generation of Latrobe Valley projects, in Proceedings Ninth International Mining Geology Conference 2014 , pp 77–84 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By Nicholas J. Grant, Michio Yamazaki

Cast copper alloys containing 10, 20, and 30 pct Ni and 0.75 to 0.80 pct Al were machine-milled into chips, then comminuted in a rod mill to fine flake powder utilizing a number of processing variables. The powders here internally oxidized, mostly at 800°C, in a low-pressure oxygen atmosphere. The consolidated powders were hot-extruded into bar stock. Room-tenmperature tension tests, stress-rupture tests mostly at 650°C, but also at 450° and 850°C, and hardness measurements after various annealing temperature treatments to study alloy stability were perfomted. Excellent room-temperature strength, high rupture strength at 650°C, and resistance to recrystallization at 1050°C were obtained. Problems in optimizing conditions for internal oxidation of Cu-Ni base alloys are discussed. THE interesting high-temperature properties of SAP' have stimulated considerable effort in the study of more refractory alloy systems where the potential for high-strength alloys at high temperature is great.2-13 A number of methods have been utilized to produce the desired fine, hard particle dispersions, of which internal oxidation2,9,7 of dilute solid-solution systems offers considerable promise by virtue of the potential for producing ultrafine, well-dispersed oxides. While most of the published works are concerned with pure metal matrices, a number of investigators have studied the effects of solid-solution strengthening.10,19 Use of more complex alloy matrices (for example, aging systems) has been unsuccessful because overaging still occurs at high temperatures in the oxide-containing alloys.14.15 Solid-solution strengthening is, however, effective at very high temperatures9,10 and might be expected to contribute importantly to the strength of oxide-dispersion strengthened alloys. For this study, internal oxidation of solid-solution alloys of copper and nickel, containing small amounts of aluminum, was chosen as the method of alloy preparation. PREPARATION OF ALLOYS Three copper alloys containing about 10, 20, and 30 pct Ni and each containing 0.75 to 0.80 pct A1 (enough to yield about 3.5 vol pct alumina) were prepared as air-cast ingots measuring 2.5 in. diameter by 6 in. high (see Table I for the analyses). Processing steps for all the alloys were as follows (also see Table 11): 1) Homogenization of the ingot at 982°C (1800°F) for 45 hr in an argon atmosphere. 2) Machine milling of ingots into fine chips. Average thickness was about 0.1 to 0.2 mm. 3) Hydrogen reduction of chips at 593°C (1100° F) for 1 hr to reduce copper and nickel oxides. 4) Rod milling of chips to finer powders. 5) Hydrogen treatment of powders as in step 3. 6) Internal oxidation of the powders. 7) Hydrogen treatment of oxidized powders as in step 3. 8) Hydrostatic compression of evacuated powders. 9) Sintering of compacts in hydrogen. 10) Hot extrusion. Variations in processing among the alloys were made in steps 4, 5, and 10 (see Table 11). In the past, two methods were utilized to internally oxidize alloy powders. Preston and Grant3 surface-oxidized dilute Cu-Al powders to obtain the necessary amount of oxygen to oxidize the solute metal (aluminum and silicon), and then permitted the formed copper oxide to diffuse and react with the solute in an argon atmosphere. Bonis and Grant4 exposed Ni-A1 and other nickel alloys to an oxygen pressure derived from the decomposition of nickel oxide at a preselected temperature, in an argon atmosphere. Both methods are applicable and can be modified to generate a range of oxygen pressures for oxidation of the solute but not the solvent metals. Procedure I: Surface Oxidation of Alloy A3, Cu-10Ni-0.76A1. Powders of -20 to +28 mesh were surface-oxidized at 500°C (932°F) to obtain the desired amount of oxygen for oxidation of the aluminum to alumina; the powder was then sealed in Vycor and heated at 900°C (1652°F) for various times up to

Jan 1, 1965

By Carolina Gomes Dias Ribeiro

The modern composite materials, especially those reinforced with synthetic fibers such as glass and carbon, have been used since last century to attend the demands required by most technological fields, from home appliances to aerospace. Natural fibers composites with biodegradable polymer matrices are considered environmentally friendly materials and currently accepted as possible substitutes for synthetic composites. These green composites can be safely discarded or composted at the end of their life without harm to the environment. Another alternative for synthetic composites is to apply natural lignocellulosic fibers as reinforcement of conventional polymer matrices and already used in the automobile industry. In addition to the environmental and societal advantages of the green composites, the lignocellulosic fiber reinforced conventional polymer composite also has economical and technical advantages. In the case of a fiber collected as a waste, the price of the composite can be considerably lower than “fiberglass”. Furthermore, with high strength lignocellulosic fibers such as sisal, ramie and malva the specific strength of a composite may approach that of “fiberglass”. Therefore the objective of the present work is to investigate the mechanical behavior of polymer matrix composites reinforced with high volumes of natural malva fibers subjected to tensile stresses.

Aug 16, 2017

By W. N. Carr, J. R. Biard, B. S. Reed

An analysis of the semiconductor injection laser is presented which is based on a phenomenological model using device and material parameters. The intent of the laser threshold analysis is not to predict from theory the actual threshold current density but rather to provide a logical means of interpreting experimental results. The device and material parameters have been selected such that they describe both the threshold conditions and quantum efficiency of the lasev. A technique is proposed whereby the current required to obtain a population inversion is predicted from device 1-V characteristics. Experimental data are presented which support the analysis. THIS investigation is concerned with the characteristics of GaAs lasers fabricated in this laboratory. However, the assumptions used in these calculations should not limit their application to GaAs alone. It is felt that the analysis is sufficiently general to be useful in describing the operation of other semiconductor-laser materials. ANALYSIS heavily doped semiconductors to be considered. The absorption and/or generation of optical radiation may be completely specified in terms of q(E) and the probability functions f,,(E) and f,(E) which define the occupancy of the valence-band and conduction-band levels, respectively. The symbols used in this analysis are listed at the end. Following the approach of all' it can be shown that the effective gain coefficient, g, in the plane of a forward-biased P -N junction is g(E)=-ai@)[1-fv(E)-fc(E)] [1I In particular Eq. [I] holds for the photon energy at which lasing occurs, Ep. Throughout the following discussion Eq. [I] is considered only for the lasing transition E = Ep. For simplicity the functional energy dependence of the various factors is omitted in subsequent equations. Unless otherwise stated the symbols used represent the values at Ep. If the analysis is limited to the P-type side of the laser junction, the function q(l -f,,) is recognized as the band-to-band absorption in the P-type material at thermal equilibrium. Under forward-bias conditions the function f, is determined by the electron quasi Fermi level in P-type material. For sufficiently large forward bias the second term in Eq. [3] will become dominant and net gain will result; i.e., g will become positive. In order to simplify the subsequent analysis several assumptions are in order at this point. a) No conductivity modulation occurs. /„ is independent of f, and therefore go is a constant. b) The P-type material is heavily doped such that the degeneracy of the valence band permits popu-

Jan 1, 1964

By Anil Mahyera

Under contract to the Bureau of Mines, a roofbolting machine has been developed which will: control torque on the bolthead to within 4 percent of a set point, control thrust to a low level (150 lbf), and implement a tightening method to minimize variability due to bolt tension decay of a group of bolts caused by differing anchor creep rates. This bolter was used to determine bolthead and thread friction factors, and to determine the effect of adding a hardened washer to the bolt assembly on the uniformity of bolt tension in the laboratory and field. Recommendations for torquing speed, bolt lubrication, use of hardened washers, and thrust level on the bolthead are made. The relationship of this system to Improved roof control is discussed, along with additional work that remains to be performed. Patent Notice Patents are pending which protect the hardware and methods of controlling tension decay as discussed in this paper.

Jan 1, 1981

By A. J. Oliver, C. E. O’Neil, I. J. Itzkovitch, V. A. Ettel

A new solvent extraction process for the separation of cobalt, copper and zinc from nickel sulphate process streams has been developed. It involves selective extraction of these elements with a quaternary ammonium thiocyanate dissolved in an aromatic diluent. The chemical principles of this process have been investigated and are described, together with background physico-chemical data relating to the use of this solvent. Long-term testing in a continuous "mini-plant" circuit gave high-purity nickel and cobalt products (Ni/Co —200011 and Co/Ni ~1000/1 respectively).

Jan 1, 1976

An upgrade to Vale?s existing Clarabelle dual-pinion, semiautogenous (SAG) mill was completed by the power and automation technology company, ABB. The mill is used to reduce the size of the ore at the company?s nickel and copper mines in the Sudbury area. The project was completed on time and on budget with an excellent safety record. Located in Ontario about 400 km (250 miles) north of Toronto, Vale?s Sudbury operations are primarily underground nickel sulfide mines, with integrated mining, milling, smelting and refining operations. One of the characteristics of Clarabelle Mill is to accept nickel-copper ore from various sources and companies and to produce a nickel-copper concentrate and copper concentrate for further processing. The size of the ore is further reduced in SAG mills, rod mills and ball mills, where all milling is done wet.

Mar 1, 2014

By Petrus Christiaan Pistorius, Farzin Fatollahi-Fard

The production of synthetic rutile—a common starting material for most titanium production processes—from iron-rich titanium minerals such as pseudorutile and ilmenite is described. The process for “upgrading” the mineral to synthetic rutile is by carbothermal reduction of the mineral while immersed in a molten salt at high temperature, followed by magnetic separation of the reduced iron. A variety of factors are also investigated, such as particle size of the mineral, the type of mineral, and the molten salt used. The solubility of iron(III) oxide in different molten salts is also experimentally determined.

Jan 1, 2016

By Michael McClintock, Bern Klein

"The high pressure grinding roll (HPGR) is a relatively new comminution technology that is gaining popularity for providing energy efficient solution to hard rock mining operations. A significant barrier to increased adoption of HPGRs is the present requirement for large amounts (excess of 2 tonnes) of sample for pilot testing, which may not be possible for most early stage projects. Three methodologies have been developed at NBK Institute of Mining Engineering at the University of British Columbia that may be used for sizing design optimization of HPGR circuits. All three methodologies use a MTS pistonpress to simulate HPGR comminution. These tests are capable of providing information regarding energy consumption, energy breakage relationship, reduction ratio, and product size distributions. In a period of slow economic development, these methodologies are critical to allow the industry to cost effectively understand the operational benefits of HPGR implementation. This paper examines previous test work done at UBC, as well as the development of an HPGR and piston press database for use in sizing and budgeting of HPGR circuits.INTRODUCTIONCurrently, the mining industry faces several challenges due to falling commodity prices and escalating costs. This has applied pressure for operations and projects to reduce costs and improve project economics. In addition engineering and metallurgical budgets have shrunk as companies try to conserve cash. Improvements and optimization of milling and comminution circuits is one area project economics may be significantly improved. By considering alternative comminution technologies such as the high pressure grinding roll (HPGR), energy operating costs may be greatly lowered. Many have begun to implement HPGR crushing as an alternative to semi-autogenous grinding (SAG) mills, including KGHM and, Sierra Gorda, and Freeport Mc-MoRan’s Cerro Verde operation. However, implementing new technology for companies with little or no HPGR experience may not be practical. An operator must consider both feasibility and economics of a circuit. Currently, consideration of the HPGR requires expensive pilot scale testing for which large sample sizes are needed. In addition, few laboratories are equipped for running pilot scale HPGR test programs. Furthermore, the results of pilot HPGR testing are dependent on the quality of the sample, which cannot represent variations across a deposit. In contrast, ball mills and SAG mills can be sized using the Bond Mill Work Indexes that require a small amount of sample which enable a number of different geological blocks to be tested to allow engineers to have a complete understanding of how the comminution circuit will perform for the life of mine."

Jan 1, 2016

By Warren A. Sheaffer

THE chief uses for copper are as a conductor of electricity and as the chief component in brasses and bronzes. For such uses, the copper must be of very high purity. H the impurities are zinc, iron, lead, arsenic, or antimony, they can be removed to a great extent by fire-refining. H, however, gold, silver, nickel, or cobalt are present, electrolytic refining is necessary. Electrolytic refining must be preceded by fire-refining and hence all impure copper must be fire-refined. The electrolytic refining of copper is most efficiently carried on when the impurities in the anodes are at a minimum. Some of the impurities tend to deposit with the copper at the cathode, while others remain in solution, decreasing the conductivity of the electrolyte and thus increasing the voltage necessary for refining. Since these dissolved impurities must be removed by continuous purifications, the amount of impurity in the anode copper should be reduced by furnace refining to some predetermined limit. Anode furnace operation aims to reduce these impurities to a minimum beyond which the cost of further furnace refining would exceed that of removing the remaining small amounts of impurities from the electrolyte. The anodes should have a fine-grain internal structure because any pieces of metal becoming detached from the anode during the electrolytic refining are inconvenient to remove from the cells and may cause short-circuits. Impurities tend to disrupt such a structure and thus form zones of weakness during corrosion. When the impurities are reduced to a satisfactory mini-mum, the anode, due to having a fine-grain structure, will corrode uniformly over the entire surface area exposed to the electrolyte. Oxides of the impurities may be volatile, in which case they pass off as flue gases, or they may form viscous slags having a lower specific gravity than molten copper, thus permitting their removal by skimming. Some impurities can be oxidized by introducing air into the bath. Due to the large solubility of oxygen in molten copper, oxygen is distributed uniformly throughout the bath and thus comes into intimate contact with all impurities. The oxides which are insoluble in molten. copper are removed either as flue gases or as slag.

Jan 1, 1942

By Diego Pacheco Wermuth

O presente trabalho apresenta os resultados do estudo e aproveitamento de cinzas leves da queima de carvão mineral em termelétrica, como reforço para o Compósito de Matriz Metálica de cobre. Foram estudados diferentes percentuais de cinzas leves como reforço para o cobre, sendo misturados estes pós através de misturador “duplo v”, compactando os pós em diferentes pressões e sinterizando os corpos de prova obtidos pela compactação. A amostra sinterizada que apresentou a maior dureza entre todos os corpos de prova sinterizados, atingindo 89 HV, foi utilizada como base para a formulação e obtenção de novos corpos de prova, que foram estudados sob condições de moagem dos pós por moinho de bolas e moagem de alta energia. A fabricação do compósito seguiu os padrões industriais do processo de Metalurgia do Pó, como a mistura e moagem dos pós, compactação dos pós e sinterização em atmosfera controlada. Foi realizado o estudo das propriedades mecânicas do compósito formado por cobre e cinzas leves, que comprovou o aumento da dureza para 122 HV. Este trabalho proporciona uma nova aplicação para as cinzas leves, utilizando estes resíduos de usinas termoelétricas como matéria prima para reforço mecânico na composição de peças à base de cobre na indústria metalúrgica.

Aug 17, 2017

By P. Nos, L. Kolbeinsen, M. W. Kennedy, A. Filzwieser, R. T. Jones, A. MacRae

Modern furnace designs often incorporate extensive use of cooled elements to achieve long campaign lives at high operating intensities. However, contact between water and high temperature fluids can result in powerful Boiling Liquid Expanding Vapour Explosions (BLEVEs). Therefore cooling such elements with water carries inherent risks when used under slag and particularly below molten metal or matte. Alternative cooling media exist that can reduce or eliminate the risk of BLEVEs. These media are analysed and discussed in the context of deeply cooled furnace elements. Important factors in selecting alternative coolants are explored including: critical heat flux, thermal limits, toxicity, flammability, unit cost, etc. Key cooling system design criteria are reviewed in the context of both traditional and alternative coolants. Results of Computational Fluid Dynamics are presented for an example tap-block cooler design using a number of selected coolants. Research needs to advance the safe use of alternative coolants are presented.

Jan 1, 2015

By L Schürmann, R Kendall

Social licence to operate is becoming part of a mining company’s DNA in the same way as health and safety. Consequently, mining companies are receiving increasing pressure from their shareholders to ensure that they add enduring value to the local communities in which they operate. Apart from the shareholders, a company has responsibility to suppliers, customers, employees, the government and the community, which means under the social responsibility model they must be accountable to the other stakeholders. External and internal challenges in mining are increasing the difficulty and complexity of mines to operate. The external mining environment has a big impact on mining operations and is driving matters such as the focus on safety, responsible mining and resource management, sustainability issues, profitability and productivity. Considering this, it is expected that the widespread implementation of Environmental, Social and Governance (ESG) related practices across the mining industry in the next ten years will increase, not just for the big players but for juniors as well. Companies, investors, governments and insurers who fail to act on ESG matters are to likely face greater risks. Demonstrating leadership in ESG will ultimately become a differentiating factor and market participants have much to gain from embracing ESG stewardship as part of their competitive advantage. Stock Exchanges have an important role to play in advancing sustainability in the capital markets. It is for this reason that the Sustainable Stock Exchanges (SSE) initiative was founded to serve as a global platform for exploring how exchanges can enhance performance on ESG issues and encourage sustainable investment. The SSE initiative provides an effective platform for dialogue between the United Nations, stock exchanges, investors, companies and regulators in the mining industry. The paper will explain why ESG reporting is crucial for the survival of a mining company and how the lack of transparency could be detrimental to its public image and shareholder relations. The paper will also identify bodies that regulate ESG reporting, as well as the available tools that provide guidelines on reporting ESG matters. Key ESG reporting parameters (at a global scale) will also be highlighted.

Jun 22, 2022

By John Goodell

CIVIL engineers seem to number in their ranks more advocates of licensing than are found among the practitioners of other branches of the pro-fession. Licensing was not originated by civil engineers but it was forced upon them in two ways. In the first place, the civil engineering profession has hangers-on like every other profession. The first legislative result of their imperfect accomplishments with which I am familiar occurred in the far West. It was found that early irrigation works were so badly planned in some cases that not only were water rights made very uncertain but considerable sums were invested in structures and ditches which proved inadequate and occasionally complete failures. Water was too valuable to be wasted in that way and money too hard to obtain. In those sections, therefore, laws were passed many years ago which made it obligatory for the design of irrigation works and other structures utilizing water to be made by engineers who had satisfied a board of examiners that they possessed the technical qualifications to plan such works properly. The basic thought on which such laws rest is the same as that on which laws governing the licensing of boiler operators rest, namely, the safety and welfare of the public. While boiler explosions still occur and irrigation works are built which are not wholly satis-factory, these laws have helped the, public, it is gener-ally agreed.

Jan 4, 1922

ALABAMA. Aldrich.-Aldrich, W. F. Anniston.-Noble, A. E., 20th St. and Wilmer Ave. Auburn.-Brown, R. L., Box 0. Bessemer.-Abbott, C. E., T. C., I. & R.R. Co. Ferguson, V., U. S. C. I. Pipe & Fdy. Co. Williams, E. P., Tenn. C., I. & R. R. Co. Birmingham.-Aldricb, T. H. Aldrich, T. H., Jr., 406 Woodward Bldg. Allen, A. W., 1616 S. 14th Ave. Bowron, J., 1401 S, 20th St. Burbidge, T. A., Browu-Marx Bldg. Coxe, E. H., Tenn. C., I. & R. R. Co. Crawford, G. G., Tenn. C., 1. & R. R. Co. Crockard, F. H., Woodward Bldg. Dimmick, F. D., Dimmick Pipe Co. Ellis, E. E., 1515 Brown-Marx Bldg. Fairbairn, C. T., Woodward Bldg. Fies, M. H., 2316 Highland Ave. Hiller, E., 516 Brown-Marx Bldg. Hillman, M. P. G., 707 Empire Bldg. Ludwig, C. P., 12th Ave. and 12th St. McCormack, G. B., Lookout Mt. Iron Co. McCrery, C., Tenn. C., I. & R. R. Co. Moffett, C. A , 909 Brown-Marx Bldg. Peters, R.. Jr., Brown-Marx Bldg.

Jan 1, 1917