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By C. Erb Wuensch

The Eagle mine is situated in the Kerber Creek mining district, Bonanza, Saguache County, Colo. The climate and topography of this district arc similar to those of mining camps of the Rocky Mountain region that lie 9000 to 12,000 ft. above sea level. The district is at the northeasterly edge of the San Juan volcanic region, in which successive Tertiary lavas have built up a high plateau resting upon earlier sedimentary formations, or the underlying pre-Cambrian complex. The latter was exposed in places by erosion previous to the eruptions. In the Bonanza district, proper, only volcanic formations, andesites and latites, are found. Dr. H. B. Patton,1 in his survey of the district, discriminates between several varieties of lavas and maps these as distinct flows. They are local variations within the same lava and it is impossible to determine any distinct line of demarkation between them. Structurally they are members of the same flow. There are three general types of vein occurrences: 1. Lead-zinc-copper-silver-gold veins in well-defined fissures with a quartz gangue; ill these, the various sulfides show a zonal arrangement. 2. Massive gray copper ores high in silver, in irregular fractures in the form of small lenses and pockets, in which little or no quartz is found. 3. Manganiferous quartz veins very low in silver and gold at the surface which, with depth, become important silver veins containing subordinate amounts of gold. These veins have a quartz gangue with an abundance of Phodochrosite. The silver is associated with small amounts of sphalerite, galena, and pyrite; fluorite also is present. The Eagle is the only mine that has been developed in the manganiferous quartz type of vein. It was discovered ill the fall of 1582, but little more than assessment work was done on the property for a number of

Jan 1, 1923

By B. W. Veal, B. S. Chandrasekhar

THE Laue method of orienting single crystals requires the use of tables of angles between crystal-lographic planes, and between zone axes. Such tables have been published for cubic crystals, and some rhombohedra12 and hexagonal3 crystals. A table of angles between planes in ß-tin has also been published;4 these angles refer to only low-index planes, and are not particularly helpful in the actual indexing of spots on a Laue photograph. Furthermore, it is often useful to know the angles between zones which share a common low-index plane. We have calculated such tables of angles for ß-tin and indium, both between planes in principal zones, and between zones passing through principal planes. The results are given in Tables I and 11. The standard formulas were used, with c/a = 0.54554 for 0-tin, and 1.07586 for indium.

Jan 1, 1962

By Donald C. Bradford

THE place of geophysics in the curriculum of a college or an engineering school has been much discussed. There is uncertainty as to whether the graduate may be called a "geological geophysicist" or a "geophysical geologist." Some have used the term "geophysical engineer." The question of the specialized undergraduate curriculum versus a general undergraduate training in the parent sciences with the addition of cultural electives has been and is still being argued. The literature during the past 10 years shows that there are two rather definite schools of thought on this subject. The prospective employer, engaged in active geophysical exploration, visualizes the graduate in terms of the routine work he will do in the field. The school administrator, grounded in many years of tradition in the cultural type of education, visualizes the graduate in terms of his position in a political and cultural society as well as in his work as a professional geophysicist. Both are right and both wrong. A third school of thought, that of the student himself, has been almost totally ignored. It would seem best, for the purpose of this paper, to treat these various points and allied material separately, and then to integrate the conclusions as a set of conditions that should be fulfilled as far as possible in the ideal curriculum. At the end the relationship of our findings to the curriculum that has been tentatively adopted at the University of Pittsburgh will be considered. DIVISIONS IN DEFINITION OF FIELD OF GEOPHYSICS Geophysics is that field of science in which geological and earth problems are solved with the use of physical and chemical techniques. Altogether too much attention has been paid to the artificial separation in this science of the commercial applications from the so-called "pure" or academic geophysics. The only real difference in the two types of work is one of scale of operations. In the commercial field the scale is large in terms of financial backing, immediate economic importance, and speed of operations. In the academic field the scale is large in terms of breadth of interests, in eventual economic importance, and length of time allowable for theoretical investigations. In exploration work the scale is small in terms of dimensions, since the methods are applicable only to the outer 20,000 ft. or so of the earth's. crust. In academic work, the student is not pressed for results of immediate economic importance, and therefore can afford to spend more time on problems that seem unimportant at the time. In the sense of background knowledge of the parent sciences necessary to the geophysicist, no essential difference can be found. Physics, chemistry, geology, and mathematics together, and in their proper proportionate amounts, form the matrix from which geophysical ideas and methods may spring.

Jan 1, 1942

By AIME AIME

THE year 1940 was an important one in the life of Carl Swartz. At the annual Institute meeting in February of that year, he was inducted into the office of Vice-Chairman of the Institute of Metals Division, and a few months later he assumed another and possibly even more important responsibility-he became the son-in-law of Robert H. Leach, genial vice-president of Handy and Harman, who had just ended his term as Chairman of the Division. The young man who took on this dual obligation in 1940, and who is now commander-in-chief of I.M.D., was born near Danville, Ill., and graduated with honors from the University of Illinois in 1923. (Ed. note: It's a small world. About the time Carl was a freshman in high school at Danville, or slightly before, the University of Illinois students held beer parties in Danville's hotel. We know; we were there.) Continuing his education at another of our fine Middle-Western colleges, Carl received his Master's degree from the University of Wisconsin and his Ph.D. from the same school in 1926. For the next nine years he worked in that splendid training school for non-ferrous metallurgists-the research laboratory of the American Smelting and Refining Co., at Barber, N. J., leaving there in 1935 to take the position of metallurgist of the Cleveland Graphite Bronze Co. in Cleveland, where he is still working (in a modern, air-conditioned office and laboratory) today.

Jan 1, 1942

cation received from Brigadicr General Thos. G. Hanson said: "It is my painful duty to communicate to you the fact of the loss of your son, Martin F. Bowles. About 11 o'clock on the night of September 3, Lieutenant Bowles, with Lieutenant Joseph B. Keckler, 355th Infantry, in command of a reconnoitering patrol of our troops, encountered the enemy. In the ensuing engagement your son received a rifle bullet through his heart. His death was instantaneous and painless. His remains were intcrred with full military honors on the 4th of September." He was promoted to First Lieutenant, but his commission did not reach him before his death. He was president of the Missouri Mining Association, Missouri School of Mines, for the year 1916-17.

Jan 1, 1920

By F. L. Wolf, A. A. Grubb

There is a tendency on the part of practical foundrymen to accept with reluctance the results of tests on sands, binders, and such materials made in the chemical laboratory alone. They feel that such tests frequently emphasize and measure properties that are of minor importance and fail to take account of characteristics that are important in determining the value of the material in actual practice. Experience seems to indicate that the most thorough and conclusive test for any new foundry material is an actual run in the foundry alongside of a standard material of known value. Such a test, however, involves certain difficulties and necessitates certain precautions. It is not always easy to obtain a fail trial for a new material. We all have certain prejuclices, which unconsciously affect our judgment to a marked degree. A practical test frequently involves so many workmen, each of whom reacts in a different manner to the test, that the personal equation becomes very complex and the true results of the test are obscured. There are times, too, when a thorough experimental trial of a material would interfere too much with the. rush of work in a department or would hazard the quality of the product to such an extent as to make it inadvisable. Under such conditions a laboratory test is advisable before the material is sent into the foundry. These tests should be made as practical as possible and so closely related to foundry practice as to give a true index to the value of a product for the purpose desired. Core sands and molding sands are as numerous "as the sands of the sea" and valy as much in quality. Old sources of supply are continually failing and new ones must be opened, so that we must continually search for new and better grades of sand. During the past year, the Ohio Brass Co. has developed tests for sands, cores, and binders which bear a close relation to the particular use to which these materials are put in the foundry and which arc fairly indicative of their value. While the tests thus far have been confined to cores and core sands, it is expected that tests for molding sand will bc developed in the future.

Jan 1, 1921

By David Donoghue

Efforts made in the year 1930 and in previous years restricted production in most of the fields of Texas to a point that was satisfactory, at the beginning of 1931, to the majority of producers and buyers. In the Panhandle, North Texas and West Central Texas districts, a few operators with refinery affiliations or contracts either ignored, or by virtue of injunction suits, did not comply with the Railroad Commission's orders, and there was some oil sold at less than posted prices, which, with the Oklahoma City difficulties, caused the first general price reduction. More could have been done perhaps to help the situation on the Gulf Coast and in the Laredo district, but natural advantages are not readily surrendered. East Texas Proration troubles in 1930 were insignificant when compared with those of 1931. In January, 1931, efforts were begun to convince the producers and citizens of East Texas of the necessity of curtailment. Opposition quickly developed and meetings were held in the towns of the region and proration denounced vigorously. Notwithstanding a strenuous campaign for additional legislation waged by many producers, the regular session of the State Legislature refused to strengthen the conservation laws and passed only the Marginal Well Bill, designed to prevent the Commission from prorating small wells. The Railroad Commission held a heated hearing on East Texas in the latter part of March. During April the Commission issued three orders based on the Yates plan for the proration of the East Texas field. Each succeeding order raised the allowable for the field. In June the opposition held more mass meetings at which a plan based on acreage was endorsed. Apparently on the theory that any plan was better than none, the Commission issued an order on July 2 embodying some of the features of the proposed plan, limiting production to 250,000 bbl. per day, and dividing the producing area into 20-acre units participating equally in the outlet. Owing to the bringing in of many wells and the many violators of the Commission's orders, production increased to such an extent that prices went as low as 5c per barrel.

Jan 1, 1932

By W. B. Mather

Arkansas' nonmetalliferous deposits are of many different types. The principal types briefly described in this paper are: clays, shales and slates; silica deposits; limestone and dolomite; barite; gypsum; celestite; nepheline syenite; greensand; phosphate; vermiculite; fuller's earth; bentonite; diamonds; sand and gravel. The future development of these deposits is expected to effect profoundly the industrial development of the state.

Jan 5, 1950

By R. A. Garling

INTRODUCTION Since the infancy of in situ uranium mining, a growing number of hydrometallurgical processes have been incorporated into pilot and commercial scale flowsheets. Although initial design efforts were geared toward maximizing uranium recovery and minimizing plant and wellfield flow circuit maintenance, recent emphasis has shifted to improved means of water conservation and aquifer restoration. As mining units approached depletion, evaporation ponds reached minimum freeboard, and state and federal agencies demanded proof of groundwater restoration, processes including mixed bed and conventional ion exchange, reverse osmosis and electrodialysis were adopted by the industry. These units served the additional function of reducing process bleed flows during mining in states where the deep disposal well permitting ice remains unbroken. This report concerns the use of electrodialysis as an alternative to the more conventional processes used in in situ mining. In addition to a brief history and description of the process, a comparison to reverse osmosis and operational data derived from testing an Ionics, Inc. 1.31 x 10-3 m /s (30,000 gallon/day) unit at the Teton-Nedco Leuenberger Research and Development pilot will be presented. HISTORY Commercially practicable electrodialysis was contingent upon the development of synthetic ion exchange membranes in 1940's. In 1952, Ionics Inc. demonstrated that the process was amenable to the treatment of salt and brackish water and, in 1954, made their first commercial sale. The following decade saw several major electrodialysis unit sales which were generally targeted for use on private or municipal potable water treatment. Major increases in membrane desalting unit capacities, facilitated by technological advances in the reserve osmosis industry, were noted during the 1970's. The development of polarity reversing electrodialysis equipment which reduced feed pretreatment requirements, increased water recovery rates, and simplified unit operation, kept Ionics Inc. competetive in the water treatment industry. Engineering advances which incorporated automated equipment, non-corrosive construction materials, and improved ion exchange membranes allowed the electrodialysis process to compete in industrial waste treatment among other commercial markets. PROCESS AND APPARATUS DESCRIPTION The electrodialysis process utilizes direct electrical current passed across a stack of alternating cation and anion selective membranes in order to achieve an electrochemical separation of ionized materials in an aqueous solution. The membrane stack has the appearance of a plate and frame filter press and auxilliary equipment includes solution pumps, electrically actuated valves, filters, piping and a direct current power source. The ion separation membranes are thin sheets of synthetic cation or anion selective resins. Attaching sulfonate or quaternary ammonium groups to the cross linked copolymer structure determines the ion selectivity of the membrane. The membranes are separated from each other in the stack by non-conductive spacers that house flow channels which route the flow tortuously and parallel to the membranes. Direct electrical current passing perpendicularly to the membranes and solution passages attracts cations toward the cathode and anions toward the anode (Figure 1). As the ions from the feed stream pass through the ion selective membranes, they become concentrated in the adjacent brine channel and are retained there by the combined attractive force of the electrode and the repelling force of the next membrane toward the electrode. Limiting factors on the degree of demineralization possible include chemical solubilities in the brine flow and the current density that will produce an unacceptable degree of polarization (Figure 1). Feed or brine solution treatment with complexing agents or acids has been successfully applied to prevent membrane scaling. Polarization can occur when sufficient current density is applied to dissociate water in the ion depleted region of the diluting compartments near the membrane surfaces. Significant polarization is evidenced by large electrical resistances across cell pairs and notable pH differences between diluting and concentrating streams. Limiting current densities have been increased in U.S. manufactured equipment by utilizing tortuous flow paths of relatively high linear velocities thereby promoting continous solution mixing. Energy consumption is due to separating electrolytes and solutions, oxidation and reduction reactions occurring in electrode compartments, overcoming electrical resistance, conversion from AC to DC power, solution pumping and auxiliary equipment actuation. A major improvement to the basic electrodialysis process was applied in 1970 which resulted in frequent, automatic cleaning and descaling of membrane surfaces. The process, polarity reversal, incorporates alternating the cathode and anode on a periodic basis while exchanging product and brine flow channels via electrically actuated values. The reversal reduces the potential of stack plugging with CaCO3 (calcite), CaSO4 (gypsum), and colloidal materials and, in most waters, eliminates feed pre-treatment requirements. For approximately two minutes during and following the reversal, off spec. water is flushed to waste or reintroduced to the feed supply. The usual feed treatment on polarity reversing electro-

Jan 1, 1982

By Frank Milliken

IN September 1937, the Ohio Copper Co. inaugurated the treatment of its copper-bearing mill tailings at Lark, Utah. These tailings had been accumulated during the regular operation of the Ohio Copper mine and mill over the period 1007 to 1019. Gravity concentration had been employed except for a comparatively short period in 1919, when flotation was used. The ore milled during that period assayed about I per cent Cu. The chief copper mineral, chalcocite, was dissemi-nated in a shattered quartzite, mainly along fracture or cleavage planes. The quartzite gangue was extremely hard and grinding to liberation resulted in excessive sliming of the "sooty" chalcocite, with consequent high tailings losses. Recovery on the seven million tons treated was prob-ably less than 6o per cent of the total copper content. As early as 1918, attempts had been made to sample the dump. In 1928, a com-plete sampling program was undertaken. The sampling consisted of seventy-four 5-in. post auger holes drilled to the full depth of the dump at regular intervals of 250 ft. Each 10-ft. portion thereof com-prised a sample for analysis. Each sample was screened, rolled, divided into three parts, dried and assayed. The reject was retained for testing purposes. From the depth of the auger holes a contour map of the dump was plotted, Fig. 1, which gives percentages of tonnage and copper content.

Jan 1, 1940

By J. E. Jopling, J. R. Chenneour, E. L. Derby, S. R. Elliott

The Marquette range, on which are situated the iron mines of Mar-quette County, together with a few in Baraga County, Mich., extends from a point 10 miles southwest of Marquette westward for 30 miles. The tracts are usually a multiple of the standard 40-acre parcel, which is the smallest government subdivision of a square mile or section. About half of the mines are held in fee, these being owned by the older mining companies. Some of them date back to about 1880, and a few are as early as 1850. During the past 40 years most of the mines opened have been on leased lands, the royalty being either for a stated amount per ton or a percentage of the selling price of the ore at the lower lake ports, or the selling price on board of cars at the mine. The first merchantable body of ore discovered in the Lake Superior district was found, in 1845, at what is known as the Jackson mine, near Negaunee. This ore was hard hematite. After unprofitable attempts had been made, in 1848, to smelt it in forges, shipments were begun to lower lake ports, which increased rapidly upon the completion of the locks at Sault Ste. Marie, in 1855, and the railroad from the mines to Marquette, in 1857. Beginning with the Pioneer, in 1858, a number of small charcoal furnaces were built to smelt a part of the product. At various points in the upper and lower peninsulas, large charcoal furnaces are still making iron from the ores of the Marquette range. In connection with these furnaces are byproduct plants. As the deposits were opened up, soft ore was encountered, but for a few years this was disregaided, as only the hard ore was used. Underground mining was begun about 1880 and during the next few years the open-pit mines producing high-grade ore were exhausted. The first mines in the district were owned by the Jackson, Cleveland, Lake Superior, Lake Angeline, Champion, Iron Cliffs, Humboldt, Republic, and Michigamme companies. Many of these companies have been merged in the holdings of The Cleveland-Cliffs Iron Co., which controls most of the tonnage of the district.

Jan 1, 1925

By A. P. Miller, T. S. Washburn

Improved procedure in the manufacture of rail steel has come as the rail user demanded better wearing qualities combined with greater unit weight. With each weight increase per lineal yard has come greater difficulty in making a product that would successfully withstand all tests that modern rails must meet. With these facts in mind, and with a sincere desire to produce a rail whose service in track would be satisfactory in all respects, the steelmaker was quick to realize that all of the factors entering into his process would have to be more closely controlled. Control of rail-steel slags was recognized as one of the most important of many interdepending factors. The object of slag control is to hold the slag compositions within a range that gives the best results with respect to economy of production, uniformity of analysis, and quality of the finished rails. The most important component of the slag from the standpoint of these production and quality factors is the ferrous oxide content. This component is a good indicator of the basicity and oxidizing power of the slag, and these largely govern the effect of the slag on the steel. Consequently, the

Jan 1, 1935

By A. P. Miller, T. S. Washburn

Improved procedure in the manufacture of rail steel has come as the rail user demanded better wearing qualities combined with greater unit weight. With each weight increase per lineal yard has come greater difficulty in making a product that would successfully withstand all tests that modern rails must meet. With these facts in mind, and with a sincere desire to produce a rail whose service in track would be satisfactory in all respects, the steelmaker was quick to realize that all of the factors entering into his process would have to be more closely controlled. Control of rail-steel slags was recognized as one of the most important of many interdepending factors. The object of slag control is to hold the slag compositions within a range that gives the best results with respect to economy of production, uniformity of analysis, and quality of the finished rails. The most important component of the slag from the standpoint of these production and quality factors is the ferrous oxide content. This component is a good indicator of the basicity and oxidizing power of the slag, and these largely govern the effect of the slag on the steel. Consequently, the

Jan 1, 1935

Accurate modeling of the semivariogram is an extremely important step in the geostatistical analysis of mineral deposits. Automatic fitting of a mathematical model is often possible but not necessarily desirable. Significant geologic and statistical information must be taken into account in the fitting process, which is not always available to the computer. Manual model fitting is, on the other hand, extremely time consuming. Interactive graphics are best suited to optimize the process. Many interactive methods are described, which are adapted to modeling semivariogram in one-, two-, or three- dimensional environments.

Jan 1, 1985

By G. St. J. Perrott

ONE of the important hazards in coal mining is the danger of ignition of explosive mixtures of methane and air or coal dust and air, or both, by the explosives used in blasting the coal. It has long been recognized that certain explosives are more dangerous than others in this respect. In America and abroad, government testing stations have been established for officially passing on the suitability of explosives for use in coal mines. In this country the Federal government is given no power to enforce the use of the approved explosives but merely publishes from time to time, through the Bureau of Mines, those explosives which have passed the tests necessary to place them on the list for use in coal mines. In spite of this lack of police power, the increase in the use of permissible explosives since the promulgation of the first list in 1909 has been rapid. In 1912, only 8 per cent. of the explosives used in coal mines were permissible; in 1925, this figure had increased to 25 per cent. While the past record of permissible explosives has been most gratifying, it is very desirable that we pave the way for further improvement in explosives and blasting methods by learning more about the mechanism of ignition of gas and coal dust by explosives. To this end a considerable amount of investigative work already has been carried out and a large amount yet remains to be done. It is the purpose of this paper to discuss briefly the effect of the characteristics of explosives and method of loading in the borehole on the liability of a blown-out shot to ignite explosive mixtures of gas or dust. For an account of the methods by which an explosive is tested for permissibility for use in coal mines, the reader is referred to Schedule 17-A of the U. S. Bureau of Mines.

Jan 10, 1926

By R. H. Johnson

The Manual of the Oil and Gas Industry, under the Revenue Act of 1918, published by the Treasury Department for the guidance of oil companies in preparing their estimates of future recoverable oil for the purpose of calculating depletion, gives the first large public collection of comparative decline curves for the whole country. It is a matter of both scientific and practical interest to so arrange these data that the pools can be readily compared. There are certain difficulties in such a comparison, however: (1) The economic limit varies from 50 to 2000 bbl. a year in different pools taken. (2) Because of this variation in economic limit, the range of data shown makes comparison possible only for wells of intermediate size. In order to be as inclusive as possible, I have taken as an expression of the rate of decline the amount of oil produced in the period during which a well drops from 3000 to 2000 bbl. a year. No period of smaller production could be used because of the high economic limit in California; and no period of larger production and yet include the small well areas of the Appalachian. As it is, the Lima-Indiana wells are excluded. In a few instances, curves were extrapolated to obtain the reading, where the curve seemed regular enough to warrant it. In general, the amount of oil, in barrels, produced while a well declined from 3000 bbl. to 2000 bbl. a year is shown in Table 1.

Jan 1, 1921

By A. H. Tousley

The cement industry is on the horns of an economic dilemma. Within the last ten years, its over- capacity in the United States has varied from 139- 127% of demand (Fig. 1). The most direct effect of this is seen in cement prices, which reached a peak in 1960, retreated steadily through 1966 and only recently climbed back to the 1960 level again. With prices in a slump and production costs estimated to be up almost 30%, there has been a steady drain on cement profits. Since 1960, labor costs have increased 86% while fuel costs have risen 18%. Meanwhile, customer service costs have also soared owing to the competition for cement customers and the wider variety of available cement products. This search for sales advantage has in turn led to a higher Blaine number, which means more grinding and hence bigger mills, more power, and, once again, higher costs. New plants as well as expansions and revisions to existing plants are also costing more owing to higher

Jan 1, 1971

By E. E. Schumacher, G. S. Phipps, H. M. Bouton

The seriousness of the present tin scarcity has stimulated large consumers of this vital metal to develop drastic conservation measures in order to extend the available supplies to cover the emergency period. By devising new soldering methods and alloys the Bell System has contributed a substantial share in the tin conservation effort. Fortunately, the changes, as far as can be determined now, have not introduced weakness into the soldered joints. Some of the new procedurcs were already in the process of development at the onset of the emergency, while others were devised under its stress. In some instances, the newly developed solders were found to be more difficult to use than the alloys previously available, and would not have been introduced under normal conditions. One major change made that previously had been under consideration will result in large savings of tin. Unless service difficulties are encountered, this modification gives promise of remaining after the emergency has passed. The change involves a reduction in the amount of solder placed on a wiped joint between the cable sheath and the sleeve. Instead of the customary full sized wiped joint, a wipe of fillet proportions is formed. Through this change, a solder saving of more than 60 per cent per joint can be realized. Plumbers and cable splicers for many years have joined lead pipes and cable sheath by a soldering process called " wiping." The name is an apt description of the operation. For a wiped joint, the sections to be united are heated by molten solder poured over their surfaces, and the resulting semiliquid mass is manipulated by wiping with cloth pads to a well rounded symmetrical form like the one shown in Fig. I. The operation requires considerable skill on the part of the splicer and close control of the composition of the solder. At first consideration, the problem of tightness in such joints seems simple but experience shows that even under the best conditions the fissures frequently found in the solder occasionally link and form a path that allows leakage to occur. In telephone cables not maintained under gas pressure, such leaks permit the entrance of water, which wets the paper-covered conductors and thereby impairs the insulation value and causes service interruptions. Ry going to an extreme and wiping off all the solder in excess of a fillet, it has been found that many causes of porosity are eliminated. Figs. 2 and 3 show cross sections of joints wiped in the old and the new ways. The saving in solder, and consequently in strategic tin, is evident. The field splicing forces find that joints are easier to make by the new method and are less likely to be porous. The metallurgical considerations that are responsible for the success of the fillet wipe are of interest. Much has been written about the wiping process of soldering cable joints and the many requirements of a good wiping solder have frequently been listed. The success of the procedure described

Jan 1, 1943

By H. M. Bouton, G. S. Phipps, E. E. Schumacher

The seriousness of the present tin scarcity has stimulated large consumers of this vital metal to develop drastic conservation measures in order to extend the available supplies to cover the emergency period. By devising new soldering methods and alloys the Bell System has contributed a substantial share in the tin conservation effort. Fortunately, the changes, as far as can be determined now, have not introduced weakness into the soldered joints. Some of the new procedurcs were already in the process of development at the onset of the emergency, while others were devised under its stress. In some instances, the newly developed solders were found to be more difficult to use than the alloys previously available, and would not have been introduced under normal conditions. One major change made that previously had been under consideration will result in large savings of tin. Unless service difficulties are encountered, this modification gives promise of remaining after the emergency has passed. The change involves a reduction in the amount of solder placed on a wiped joint between the cable sheath and the sleeve. Instead of the customary full sized wiped joint, a wipe of fillet proportions is formed. Through this change, a solder saving of more than 60 per cent per joint can be realized. Plumbers and cable splicers for many years have joined lead pipes and cable sheath by a soldering process called " wiping." The name is an apt description of the operation. For a wiped joint, the sections to be united are heated by molten solder poured over their surfaces, and the resulting semiliquid mass is manipulated by wiping with cloth pads to a well rounded symmetrical form like the one shown in Fig. I. The operation requires considerable skill on the part of the splicer and close control of the composition of the solder. At first consideration, the problem of tightness in such joints seems simple but experience shows that even under the best conditions the fissures frequently found in the solder occasionally link and form a path that allows leakage to occur. In telephone cables not maintained under gas pressure, such leaks permit the entrance of water, which wets the paper-covered conductors and thereby impairs the insulation value and causes service interruptions. Ry going to an extreme and wiping off all the solder in excess of a fillet, it has been found that many causes of porosity are eliminated. Figs. 2 and 3 show cross sections of joints wiped in the old and the new ways. The saving in solder, and consequently in strategic tin, is evident. The field splicing forces find that joints are easier to make by the new method and are less likely to be porous. The metallurgical considerations that are responsible for the success of the fillet wipe are of interest. Much has been written about the wiping process of soldering cable joints and the many requirements of a good wiping solder have frequently been listed. The success of the procedure described

Jan 1, 1943

By D. R. Mash

A strong yield point with attendant enhanced mechanical properties was found in commercially pure beryllium under certain conditions of heat treatment. Beryllium specimens also responded to both quench and strain aging treatments. Based on these results, a possible means of obtaining increased normal temperature mechanical properties is suggested. COMMERCIALLY pure beryllium has been found to exhibit the yield point phenomenon and several other aging manifestations under certain conditions of heat treatment. This behavior is not surprising in view of the present accumulation of experience regarding such effects in numerous metals; but in addition to extending this experience to include beryllium, the present study is of interest because aging effects are generally associated with the presence of small amounts of solute elements. The well known lack of tensile ductility in beryllium at normal temperatures is also considered to be due to impurities in some way. In the present investigation, the view was taken that beryllium of commercial purity (greater than 98 pct) should be considered as a dilute alloy and that precipitation phenomena may well exist which could lead to enhanced mechanical properties. In connection with this possibility, published data on the variation of mechanical properties with temperature are of interest. For example, Fig. 1 illustrates the variation of ductility (percentage of elongation) and ultimate strength as a function of temperature for beryllium of various histories.* Although these curves are somewhat schematic in nature, they clearly indicate the possibility that precipitation of an unstable phase and/or aging effects occur during tests in the region 400" to 700°C. The existence of such behavior should be recognized as affecting the properties of the commercial material and perhaps can be employed advantageously. Experimental Method All testing was done at room temperature using a Baldwin universal testing machine. A microformer extensometer was used in conjunction with a micro-former-type stress-strain recorder. All tests were conducted at constant loading rate, the slowest rates being used. This corresponded to 120 lb per min in the 1200 lb full scale range and 300 lb per min in the 6000 lb full scale range. After the rate of loading was set in the elastic range of the material during the early part of the test, no further adjustments were made, allowing the test to proceed at that setting. In the plastic region of the curve above the yield region, strain rates of from 0.002 to 0.006 in. per min were regularly obtained. All experimentation was carried out on specimens machined from the same lot of beryllium, lot No. Y5036BP. Table I shows the chemical analysis as furnished by the supplier, Brush Beryllium Co., as well as the standard specifications to which commercial beryllium is produced. Both 1/4 in. thick hot pressed plate and ½ in. round hot pressed and warm extruded rods were obtained. The history of the material is reported to be as follows: 1—Beryllium metal plates, produced from a standard hot pressed QMV beryllium metal block 4x15x40 in., were cut off and finished machined to 1/4x6x12 in. flat plates. The original hot pressed block was made by hot pressing —200 mesh vacuum cast attri-tioned powder at about 1050°C under vacuum. 2—Beryllium rod was hot pressed and warm extruded. Extrusion billets were machined from the regular hot pressed blocks followed by extrusion at 425°C. The extrusion was done without jacketing, and graphite was used as a lubricant. The rods were then straightened at 720 °C, after which they were annealed at 800°C for 15 min. Both flat tensile specimens and round tensile specimens were tested. The former were machined from the plate stock into standard specimens according to specifications shown in ASTM E8-52T. The nominal cross-section was 0.25x0.500 in. and the gage length was 2 in. The round specimens were

Jan 1, 1956