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By Raymond O. Ladoo

FUSED quartz is a glass made by the fusion of nearly pure silica. Some confusion in terminology exists but in the trade today "fused quartz" generally refers to the perfectly transparent colorless product made from rock crystal whereas "fused silica" is a white, translucent product made from silica sand. Vitrified silica is the term preferred by purists for all quartz glass, but it lacks the definiteness of -the trade terms. Since the raw materials, methods of production, and properties of the finished products arc different for the two types, the trade terms are preferred. As fused quartz is amorphous, it-physical properties differ greatly from those of quartz crystal. Lacking crystallographic directions and having no piezo-electric properties, fused quartz. of course, has no value for the making of radio oscillator plates; but it does have other valuable and unique properties. Perhaps the 'best known and most useful properties are its extremely low coefficient of expansion and its ability to transmit short-wave ultraviolet radiant energy. Crystal quartz not only has an aver-

Jan 1, 1947

By D. M. Wade, F. F. Redfield

PRODUCTION at Aguilar started in 1936 and by 1942 the mine had reached a peak of 25,000 tons a month. Present production is only about 60 per cent of this capacity because of difficulties in railroad transportation and the rationing of fuel oil brought about by the war. In the early years, cut-and-fill stopes were tried, but square sets were found to be the most practical method in the southern section of the mine, where blocky, treacherous ground and greater mining widths are prevalent. Square sets and opencut mining were the rule until 1942, when it became increasingly difficult to get mine timber. The ore beds in the northern section of the mine were found amenable to cut-and-fill stoping as the rock was firmer and the veins narrower. At present 69 per cent of the ore comes from cut-and-fill stopes, 27 per cent from opencut, and only 4 per cent from square-set stopes. Massive galena and sphalerite with comparatively little quartzitic gangue constitutes the higher-grade ore. The gangue minerals that can be detected by eye in low-grade ore are rhodonite, wollastonite, and pyrrhotite. Wall rocks range from shale to quartzite, with occasionally a little limestone.

Jan 1, 1947

By Harvey S. Mudd

WHEN talking about Europe it is well to endeavor to keep politics and economics apart but they have become so intermingled in recent years that the discussion of one topic inevitably leads to the other. Economic influences formerly prevailed over politics but today national and international economies are governed by political forces. Commerce in raw materials, food, and manufactured products is now so restricted by governmental controls that the capacity of the world to produce and to consume, to exchange goods and to pay for them, cannot be gauged by the past or predicted by a multitude of experts. In prewar days there were some yardsticks but today there are none. Thus it is hazardous to make forecasts, for in all fields of human effort the world has been cast upon an uncharted sea.

Jan 1, 1947

By T. L. Joseph

A DEMAND for specialized knowledge has directed engineering curricula towards competency in some particular field or occupation. Preparation for life in a broad sense of completeness has received little consideration. Ways and means are needed for weaving some of the threads of liberal education into the fabric of engineering education. Any effort to develop a humanistic-social stem of engineering education will depend largely upon the content of the courses and the type of instruction offered. Many of the courses in college curricula are intended to lay a foundation for more advanced courses to be taken later by those. who specialize in some particular field. Students in other fields lack the background necessary to take the advanced courses and have too much detailed information, soon forgotten, forced upon them if they pursue the foundation courses. To develop a humanistic-social stem for engineering education existing catalogue courses selected should follow some general plan aimed towards broad educational objectives. Courses packed with detailed factual information are necessary for the stu-

Jan 1, 1947

By W. T. lsbell

HERCULANEUM, MO., about thirty miles south of St. Louis on the Mississippi River, is the site of the lead smelter of the St. Joseph Lead Co. The lead concentrates come by rail from the Flat River district and from three properties in Madison County, Missouri; from the Balmat division in St. Lawrence County, New York; a small tonnage from the Tri-State district; and occasionally from the Aguilar property in Argentina. The average grade is 67 to 68 percent lead and 1 to 3 oz of silver. The bulk of the material is flotation concentrate, with some gravity or table concentrate. No secondary metals, outside drosses, or any materials high in bismuth, arsenic, or antimony are treated. All concentrate is received in box-caps and is unloaded directly from a trestle into the concentrate bins at the roaster plant. Flux, coke, and any miscellaneous lead-bearing material is either unloaded directly into bins or unloaded with a locomotive crane. All moving and switching of cars is done with two thirty-ton steam locomotives. Shipping facilities for the plant are provided by the Missouri-Illinois Railroad. Water for the plant and for fire protection is obtained from a dam built in a near-by creek. Drinking water both for plant and town is obtained from

Jan 1, 1947

By Jay J. Burns

TWO zinc concentrating mills are operated by the St. Joseph Lead Co. in St. Lawrence County, N. Y. The Edwards mill is operating at present only sixteen hours a day treating 400 tons daily. The metallurgy at Edwards presents no unusual problems therefore this discussion is mainly limited to the metallurgy of the Balmat ore. The Balmat mill has a capacity of 1,250 tons per day and the operating crew consists of three shift bosses each with five millmen per shift. Two crusher operators work on each of two shifts and one cleanup man on day shift. The repair crew is made up of a foreman and three repairmen, one of the repairmen being capable of taking over any operating job in the mill from shift boss down. Each millman is capable of handling the next job in line and several men in the yard crew are broken into handling the start-off job in the mill so that temporary shortages of men do not cause extensive overtime. Sphalerite, pyrite, and galena, the principal ore minerals, occur in a gangue of calcite, dolomite, and silicates, especially diopside, plus tremo-

Jan 1, 1947

By R. M. Briney

A RETURN to nonwar conditions characterized the year 1946. The acquisition and forced use, under Government auspices, of low-grade and uneconomic ores, both foreign and domestic, ceased in 1945, but there was some carry-over into the early months of 1946. The world shipping situation delayed the procurement of some foreign ores, but conditions were improving by the end of the year. No actual shortage of any important alloy was experienced, hence the industry was able to make prompt shipment of orders placed. Price levels of ferroalloys, which had remained virtually constant through the war years, were forced upward, with increases on specific products as conditions necessitated. Standard ferroman-ganese and low-carbon ferrochrome were notable exceptions in that their price did not change. No new ferroalloy smelting plants were constructed. The Defense Plant Corp.. sold the works at Ashtabula, Ohio, to the Electro Metallurgical Co. A new type of ferroalloy furnace was described at the Birmingham meeting of the Electrochemical Society. Known as the "Elkem Rotary Furnace" it is distinguished by a rotating shell. The whole furnace, including shell, refrac-

Jan 1, 1947

By W. D. France, H. l. Burghoff

FABRICATORS of copper and copper alloys have contended with the problems of reconversion during the past year in endeavoring to return to the full-scale production that is demanded of them. The problems have not been easy, for the industry, like so many others, has had to deal with strikes of long duration, and material shortages, particularly in the raw materials, copper, zinc, lead, and tin. Despite all these obstacles, it was possible to gear production to new peacetime records during the latter part of the year. This was made possible not only by the use of multiple shifts of personnel, but also by the improved production equipment, the development of which had been stimulated by wartime necessity. The work of installing new and better equipment is still continuing, and virtually every company is engaged in improving or planning to improve its processes.

Jan 1, 1947

By John D. Bardill

This report covers the magnetic surveying done in the Plattsburg area , which was part of a general survey, of magnetite deposits in New York State . Other areas being surveyed are the Star Lake district , St. Lawrence County ; Brewster district , Putnam County; and the Sterling district , Orange County. Reconnaissance indicated an area about 3 miles long and 1,200 feet wide , but detailed surveys have been completed on only a portion of that area . In several districts , surveys of this type have served as a basis in the selection of areas for exploration by diamond drilling by the Bureau of Mines .

Jan 1, 1947

By E. J. Bolitho

"The paper covers the activities of the Government Miners' Training-Schools. It argues that its success is proved by the steady demand for miners trained at the Schools; by the large numbers of ex-apprentices who hold responsible official positions in the industry; and bv the probable expansion of the organization in the near future to meet the never-ending call for trained personnel."

Jan 1, 1947

By Dwight L. Sawyer

IF it had not been for the testimony of former Secretary of the Interior, Harold L. Ickes, before the Senatorial investigating committee the public would have heard little about the Federal Government's suit against California for the ownership of the tidelands. The Ickes-Pauley dispute brought to public attention that the California tideland oil deposits are the last remaining large Federal oil reserves. Ickes contends that these tideland oil deposits belong to the nation for the benefit of all the people of all the states and not solely to the State of California. Ickes also accused California oil man Ed Pauley of offering to give $330; 000 to the Democratic party fund if Ickes would drop the Federal Government's suit against the State of California for the ownership of said tidelands. The tidelands may be considered as the land bordering the coast line between mean high tide and outward under the ocean for a distance of a marine league, or about three statute miles. This strip of land along the coast of southern California contains large oil deposits which have a present and future prospective value of several billion dollars.

Jan 1, 1947

By F. O. Garrabrant

Power is furnished to the Climax Molybdenum Co. by the Public Service Co. of Colorado over two 100,000-volt lines to a bank of three 3333-kva. transformers 100/13.8 kv. These transformers are so designed that with the addition of forced cooling their capacity may be increased 331/3 Per cent at 12,000-ft. altitude. Under present conditions, these transformers are operated at 140 per cent of their rating with forced air cooling. On the secondary side of this bank there is a 15-kv., 1200-amp. Westinghouse oil circuit breaker provided with automatic reclosing relays allowing three successive short circuits before lockout. From this breaker 13.8-kv. power is transmitted to a central switching station (Fig. I) where all circuits radiate to the different operations of the property. Each circuit is protected by a 23-kv., 600-amp. oil circuit breaker with by-pass and isolating disconnecting switches.

Jan 1, 1947

By E. J. Lintner, J. R. Thoenen

During the period 1937-40 and until peacetime research was superseded in 1941 by wartime activities , the junior author was engaged in studies regarding the relative efficiency of operating methods in quarries producing crushed stone for mineral aggregates . The results of some of these studies were published as reports of investigations in 1939 and 1940 ; / others were discontinued due to war demands on personnel and time . The published reports discussed the efficiency of particular quarry operations with respect to the time consumed and without reference to costs or mechanical factors . • At the time , the field data were collected for the published reports other data were collected relative to the relationship of the numerous variable factors inherent in the operation of a churn drill to the ability of the drill to produce blast holes . The churn drill is essentially a crusher and depends. for its performance upon the foot-pounds of energy it can impart to the cutting edge of its bit . The gravity stamp mill , so well-known in western gold mines , is essentially the same type of crusher . The ratio of foot- pounds necessary to crush the rock , to the total theoretical energy developed by the falling churn- drill tools , affords a good means of evaluating the efficiency of the tool . This does not include to tal over-all efficiency involving the mechanical equipment of the drill itself or its power unit .

Jan 1, 1947

By N. L. Wimmler

"INTRODUCTION The Southern Cross district in Deer Lodge County, Mont., has been chiefly a gold producer. Most of the production has come from gold-bearing hematite-limonite ores. Some of these ores were mined and shipped to smelters for use as flux in smelting copper ores. A magnetite deposit in the Pomeroy property, containing no gold or other economic nonferrous minerals, was mined from 1921 to 1923, the ore being shipped to smelters for flux.The iron-bearing deposits in the Southern Cross area were examined by Bureau of Nines engineers/ on June 28, 1943, and October 14, 1943. As a result, a Bureau exploration project was recommended; it was conducted during 1944. A magnetometer survey was first made of the magnetite-bearing area at and in the vicinity of the Pomeroy property. Exploration by diamond core drilling was then conducted within this area, and in the Southern Cross and Hold Fast properties. The cyanide tailings dump at the Hold Fast mill was sampled by auger drilling.This report presents the data obtained by the Bureau of Mines exploration."

Dec 1, 1946

By R. G. Knickerbocker, T. E. Evans, D. R. Torgeson

"INTRODUCTION Sponge iron is a product resulting from the reduction of an iron oxide at such a low temperature that fusion does not occur, and the reduced particles retain substantially the same shape as the original ore. The removal of oxygen in the reduction process leaves the metal porous and reactive. Sponge iron may be compared in general to a chemically precipitated substance insofar as reactive properties are concerned. The high specific surface and the orientation of metallic structure are factors which probably contribute to the reactive properties of sponge iron.The term ""gaseous reduction,"" as applied to iron ores, required clarification. Strong evidence exists, for example, that ore is partly reduced to sponge iron by carbon monoxide in the blast furnace at temperatures around 800° C. at a point that may be as high as 30 feet above the tuyores. In 1923 and 1924, Sims and Wood attempted to reduce iron oxide with carbon in an Arsem vacuum furnace at 980° C. These investigators found that only 6 percent of the iron was reduced to metal when the iron oxide-carbon mixture was heated for 1 hour under evacuated conditions, whereas at atmospheric pressure 70 percent of the iron was metallized. Their results indicate that the process of iron-ore reduction at temperatures below the melting point of the ore may proceed largely, if not entirely, by the action of reducing gases even when the reducing agent is solid carbon. Therefore, the term ""gaseous reduction,"" as used heroin, is defined as a process in which iron ore is brought into intimate contact with a reducing gas produced in separate-equipment from the reduction chamber itself.A large amount of pilot-plant development on gaseous reduction of iron ores has been carried out by the Bureau of Mines at the Boulder Experiment Station and had as its objective the reduction of fine iron ore by means of producer gas. The use of use gas was prompted by two considerations: First, the possible utilization of large reserves of Western noncoking bituminous coals and lignites contiguous to iron-ore drewwing; and second, an investigation of the results that might be achieved in the pilot-plant gaseous reduction of fine iron ores by means of a relatively reducing gas. The results obtained, it was felt, would be of considerable value in indicating the direction which gaseous reduction experimentation must take for the development of a commercially practicable and economic process for the production of sponge iron."

Dec 1, 1946

By Vernon Helm, John S. Ball, Welton J. Wenger, William E. Haines

"INTRODUCTION Although the presence of sulfur causes many petroleum’s to be classified as ""low-grade"" because of the difficulties encountered in manufacturing products to meet rigid specifications, the petroleum industry is finding it necessary to use such crude oils to satisfy present needs. As the demand for petroleum products increases, and available reserves diminish, this utilization of high-sulfur crude oils will be accentuated. Programs designed to supplement the supplies of fuel available from petroleum by the manufacture of synthetic fuel from natural gas, shale oil, and coal are in progress. Such fuels, especially shale oil and, less so, oil from the hydrogenation of coal, also contain sulfur compounds which must be effectively removed. Thus, the need for fundamental research on the sulfur compounds that may be expected in petroleum and allied products is becoming greater as the industry is forced to call upon all available resources to meet the demand for petroleum products. In recognition of this need, the Bureau of Mines has inaugurated a long-range program assigned to furnish fundamental data concerning the presence, characteristics, and effects of sulfur compounds in petroleum and its products."

Dec 1, 1946

By Cleo Griffith Rall, D. B. Taliaferro

The method for determining oil and water saturations described herein has been used successfully for several years in the core laboratories of the Bureau of Mines. The apparatus constructed according to the original specifications has proved very satisfactory; in fact, it has been widely adopted by core laboratories throughout the petroleum industry. The writers have found that the method gives reproducible results, the degree of accuracy depending largely on the attention to details given by the operator. The relative importance of these details of procedure and the design of the apparatus are discussed in this report. In September 1940, the Bureau of Mines published a report describing a method used in its laboratories for the determination of the water content of oil-field cores. The procedure was essentially the same as that adopted by the American Society for Testing Materials for the determination of the water content of petroleum products, although the apparatus and technique were altered slightly to increase the precision of the method and to adapt it to the characteristics of the material to be tested. The report also contained a description of the method used at that time in the Bureau’s core laboratories for measuring the oil content of a core, utilizing the sample on which the water-saturation determination had been made. The procedure involved the transfer of the weighed sample, from which the water had been distilled and measured, to a Soxhlet extractor and the removal of the remaining oil by means of a suitable solvent. Soon after the report was published, the water-determination apparatus described therein was modified so that both the oil and water contents of a core sample could be determined simultaneously. This method, which has been described by Yuster, is now widely used throughout the industry.

Dec 1, 1946

By R. T. Artz

Disposal of sewage is an important part of mine sanitation. Improper... handling and.disposing of sewagerare conducive to the spread of disease and often add foul and nauseating odors to the mine air. The diseases spread by unsafe methods of disposing of waste in mines are typhoid fever, cholera, amebic dysentery, hookworm, and other intestinal diseases due to parasites. Sanitary toilet facilities, with a good sewage-disposal system, each maintained in good order at all times, should help to prevent the spread of diseases transmitted by intestinal body wastos. The metal and nonmetal-mining industries have recognized the impor-dma tance and need for disposing sewage properly; accordingly, facilities of some sort are installed and need today in most large mines. The coal-mining industry has given little thought to the disposal of sewage underground; however, in most mines of the anthracite industry, the inflow of large vol- unes of highly acid mine water and the extensive drainage system required to remove this water provide a natural means for disposing of sewage.

Dec 1, 1946

By Almon F. Robertson

"INTRODUCTION At various times, North Carolina has supplied small quantities of brown-iron ore to the furnace o the South. Between 1917 and 1920, the quantity reported to the Federal Geological Survey was 126,000 tons. Most of this came from Cherokee County. 3/In furtherance of the program initiated by the Bureau of Mines to develop additional reserve of iron ore during the emergency, the Cherokee County deposits were examined by an engineer 4/ of the Bureau of Mines, and work was recommended on,12 properties.The project was begun in April 1944 and continued intermittently until April 1945, when work was stopped. During this period, eight properties were explored, and an additional property was mapped.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch; Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director."

Nov 1, 1946

By F. A. Rutledge, H. Marstraander, J. H. Hulbert, G. A. Apell

"INTRODUCTION The inability of Alaska coal mines to supply the quantity of coal required by public and private consumers and by the armed forces in Alaska caused the Coal Procurement Section of the Alaska Department, U. S. Army, to be established. It proposed to investigate the coal deposits and to expedite production of coal. The Bureau of Mines has closely cooperated in this program and was in direct charge of exploration. As to develop and equip an underground coal mine would have taken time and the need for coal was acute, a deposit that could be prepared for mining quickly was desirable. Several such deposits of stripping coal were known to occur in the Nenana field and were examined by the Bureau. One of these, the Diamond strip mine 4 miles west of Healy, was brought into production late in the fall of 1943. This mine was operated for the Army Coal Procurement Section by the C. F. Lytle Co. and the Green Construction Co.The Roth property, or Leasing Block No. 28, in the Healy Creek Valley offered the largest available tonnage of both stripping coal and total reserves. A program of exploration by the Bureau of Mines was inaugurated in 1943 and completed in 1944. Field parties of the Federal Geological Survey mapped the area had correlated the coal beds during the 1944 and 1945 summer seasons."

Nov 1, 1946